The word "transistor" is a combination of the words "transfer" and "varistor." The term describes how these devices worked in their early days. Transistors are the main building blocks of electronics, in much the same way DNA is the building block of the human genome. They are classified as semiconductors and come in two general types: the bipolar junction transistor (BJT) and the field effect transistor (FET). The former is the focus of this discussion.
Types of Bipolar Junction Transistors
There are two fundamental types of BJT arrangements: NPN and PNP. These designations refer to the P-type (positive) and N-type (negative) semiconductor materials from which the components are constructed. All BJTs therefore include two PN junctions, in some order. An NPN device, as the name suggests, has one P region sandwiched between two N regions. The two junctions in the diodes may be forward-biased or reverse-biased.
This arrangement results in a total of three connecting terminals, each of which is assigned a name specifying its function. These are called the emitter (E), the base (B) and the collector (C). With an NPN transistor, the collector is connected to one of the N portions, the base to the P portion in the middle and the E to the other N portion. The P segment is lightly doped, while the N segment at the emitter end is heavily doped. Importantly, the two N portions in an NPN transistor cannot be interchanged, as their geometries are completely different. It may help to think of an NPN device as a peanut-butter sandwich, but with one of the slices of bread being an end piece and the other one from mid-loaf, rendering the arrangement somewhat asymmetrical.
Common Emitter Characteristics
An NPN transistor may have either a common base (CB) or a common emitter (CE) configuration, each with its own distinct inputs and outputs. In a common emitter set-up, separate input voltages are applied to the P portion from the base (VBE) and the collector (VCE). A voltage VE then leaves the emitter and enters the circuit of which the NPN transistor is a component. The name "common emitter" is rooted in the fact that the E portion of the transistor integrates separate voltages from the B part, and the C part emits them as one common voltage.
Algebraically, current and voltage values in this set-up are related in the following way:
Where β is a constant related to intrinsic transistor properties.
About the Author
Kevin Beck holds a bachelor's degree in physics with minors in math and chemistry from the University of Vermont. Formerly with ScienceBlogs.com and the editor of "Run Strong," he has written for Runner's World, Men's Fitness, Competitor, and a variety of other publications. More about Kevin and links to his professional work can be found at www.kemibe.com.

Is é an focal "tranzistóir" comhcheangal de na focail "aistrithe" agus "varistor". Déanann an téarma cur síos ar an gcaoi a raibh na feistí seo ag obair ina laethanta tosaigh. Is iad trasraitheoirí príomhbhloic tógála leictreonaic, ar an mbealach céanna is é DNA an bloc tógála den ghéinóm daonna. Déantar iad a aicmiú mar leathsheoltóirí agus tagann siad i dhá chineál ginearálta: an tras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras-thras. Is é an chéad cheann a bheidh i ndán don phlé seo.
Cineálacha Tránsastairí Comhcheangail Dhá-Polair
Tá dhá chineál bunúsach socruithe BJT ann: NPN agus PNP. Tagraíonn na hainmneacha seo do na hábhair leathsheoltóra de chineál P (deimhneach) agus de chineál N (diúltach) as a ndéantar na comhpháirteanna. Dá bhrí sin, tá dhá chearnóg PN ag gach BJT, in ord éigin. Tá réigiún P amháin idir dhá réigiún N i bhfeiste NPN, mar a thugann an t-ainm le fios. Is féidir an dá nasc sna díodanna a bheith dírithe ar aghaidh nó ar ais.
Tá trí chríochfort nascála sa chomhlacht seo, agus ainm a shanntar do gach ceann acu a shonraíonn a fheidhm. Tugtar an t-eisiúintí (E), an bonn (B) agus an bailitheoir (C) orthu seo. Le tránsastair NPN, tá an bailchríoch ceangailte le ceann de na codanna N, an bonn leis an gcuid P sa lár agus an E leis an gcuid N eile. Tá an rannán P dopáilte go héasca, agus tá an rannán N ag deireadh an astaitheora dopáilte go mór. Tá sé tábhachtach a thabhairt faoi deara nach féidir an dá chuid N i n-tranzistóir NPN a mhalartú, toisc go bhfuil a gcuid géimeatraíochtaí go hiomlán difriúil. D'fhéadfadh sé cabhrú smaoineamh ar ghléas NPN mar shantéibhe peanut-butter, ach le ceann de na sliceanna aráin a bheith ina phíosa deiridh agus an ceann eile ó lár an chnapáin, rud a fhágann go bhfuil an socrú beagán neamhréireach.
Feidhmeanna Coitianta Emitteora
Is féidir le tras-thrasdaitheoir NPN a bheith ina chomhchoinníoll bunchoiteann (CB) nó ina chomhchoinníoll astaithe (CE), agus a iontrálacha agus a aschuir féin ar leith ag gach ceann acu. I socrú coiteann astaitheora, déantar voltais ionchuir ar leithligh a chur i bhfeidhm ar an gcuid P ón mbonn (VBE) agus ón mbainisteoir (VCE). Fágann VE voltais an scaoileoir ansin agus téann sé isteach sa chiorcad ar comhpháirt den idirthráthálaí NPN é. Tá an t-ainm "scagaire coiteann" bunaithe ar an bhfíric go gcuimsíonn an chuid E den thras-thrasdaitheoir voltais ar leithligh ón gcuid B, agus go scaipeann an chuid C iad mar aon voltas coiteann.
Tá na luachanna reatha agus voltais sa leagan seo ceangailte go halgáiriúil ar an mbealach seo a leanas:
Sa chás seo is gnáthchomhánta é β a bhaineann le hairíonna intrinsic tras-thrasdaire.
Maidir leis an Údair
Tá céim bhaitsiléara ag Kevin Beck i fisice le mionaoisigh i matamaitic agus ceimic ó Ollscoil Vermont. Roimhe sin le ScienceBlogs.com agus le heagarthóir "Run Strong", scríobh sé do Runner's World, Men's Fitness, Competitor, agus foilseacháin éagsúla eile. Is féidir tuilleadh faoi Kevin agus naisc lena chuid oibre gairmiúil a fháil ag www.kemibe.com.


The idea of going to court for custody of your children is a stressful thought alone. Combine that with legal terms and questions being thrown at you by the opposing attorney and the judge, and it can become overwhelming. Understanding what these legal terms mean will hopefully give you an idea of what to expect and help decrease the stress level while in court. In the coming weeks we hope to fully explain all of the legal terms surrounding custody including, physical custody, legal custody, sole custody, primary custody, joint custody, secondary custody, and visitation.
A child custody order must specify where a child will live (physical custody) and whether one or both parents can make decisions about the child (legal custody). The terms sole, primary, secondary, and joint custody, as well as the term visitation, are the terms that describe the quantity each parent has of the physical and legal custody of the minor child(ren). This week we will explore the term physical custody and the different terms used to describe how much physical custody each parent has with the child(ren).
The term sole physical custody applies where the children live with one parent only and the other parent does not have any visitation. Sole physical custody is rare and usually only occurs when the other parent is unfit, has abused or neglected the child(ren), or has abandoned the child(ren) and is not involved in their lives (check back in the coming weeks for a better explanation of these terms). Even if one of these situations applies, the other parent may still receive visitation that is either supervised or significantly limited. If this parent receives any visitation, then the parents have joint physical custody rather than one parent having sole physical custody.
Joint physical custody describes when both parents have some sort of physical time with the child(ren), whether it is supervised or unsupervised and regardless of how much or how little physical time each parent has. Joint physical custody can also describe an equal split of time with the children though, which is commonly referred to as a 50/50 split of physical custody.
For example, primary and secondary physical custody are forms of joint physical custody because each parent has time with the children.
When the parents do not have an equal share of physical time with the children, the parent with more physical time has primary physical custody and the other parent has secondary physical custody in the form of visitation. For example, when one parent has the children every other weekend only, this parent has secondary physical custody in the form of visitation. The other parent has primary physical custody of the children.
If you want to discuss your particular physical custodial arrangement or how to change it, you can call 919-576-7550 to schedule a consultation with one of our family law attorneys. Each case is unique and is important to talk to an attorney about the facts specific to your individual case.
Check back next week for an explanation of legal custody.

Is smaoineamh strusach é an smaoineamh go rachaidh tú chun cúirte chun caomhnóireacht do pháistí a fháil. Cuir sin le téarmaí dlí agus ceisteanna a bhíonn á gcaitheamh agat ag an aturnae opponent agus an breitheamh, agus d'fhéadfadh sé a bheith thar a bheith tromchúiseach. Tá súil againn go dtabharfaidh tuiscint ar na téarmaí dlíthiúla seo smaoineamh duit ar a bhfuil súil agat leo agus go gcabhróidh sé leis an leibhéal strus a laghdú agus tú sa chúirt. Sna seachtainí atá le teacht tá súil againn go míneoidh muid go hiomlán na téarmaí dlíthiúla go léir a bhaineann le coimeád lena n-áirítear coimeád fisiciúil, coimeád dlíthiúil, coimeád aonair, coimeád bunscoile, coimeád comhpháirteach, coimeád tánaisteach, agus cuairteanna.
Ní mór a shonrú i n-ordú cúram leanaí cá mbeidh cónaí ar an leanbh (cúram fisiciúil) agus an féidir le tuismitheoir amháin nó an dá thuismitheoir cinntí a dhéanamh faoin leanbh (cúram dlíthiúil). Is iad na téarmaí úd, príomh, dara leibhéal, agus co-chaomhnóireacht, chomh maith leis an téarma cuairt, na téarmaí a thuairiscíonn an méid atá ag gach tuismitheoir de chaomhnóireacht fhisiciúil agus dlíthiúil na leanaí mionaoiseach. An tseachtain seo, scrúdóimid an téarma caomhnóireacht fhisiciúil agus na téarmaí éagsúla a úsáidtear chun cur síos a dhéanamh ar an méid caomhnóireachta fisiciúil atá ag gach tuismitheoir leis an leanbh (í).
Baineann an téarma cúram fisiciúil aonair nuair nach bhfuil ach tuismitheoir amháin ag na páistí agus nach bhfuil aon chuairte ag an tuismitheoir eile. Tá caomhnóireacht phearsanta aonair annamh agus de ghnáth ní tharlaíonn sé ach nuair nach bhfuil an tuismitheoir eile oiriúnach, gur mhí-úsáid nó gur thréig sé an leanbh (í), nó gur thréig sé an leanbh (í) agus nach bhfuil baint aige lena saol (féach ar ais sna seachtainí atá romhainn chun míniú níos fearr a fháil ar na téarmaí seo). Fiú má tá ceann de na cásanna seo i bhfeidhm, d'fhéadfadh an tuismitheoir eile cuairt a fháil a bhfuil maoirseacht air nó a bhfuil teorainn shuntasach aige. Má fhaigheann an tuismitheoir seo aon chuairte, ansin tá co-chaomhnóireacht fhisiciúil ag na tuismitheoirí seachas tuismitheoir amháin a bhfuil caomhnóireacht fhisiciúil aonair aige.
Déanann co-chúram fisiciúil cur síos ar an gcaoi a mbíonn am fisiciúil ag an dá thuismitheoir leis an leanbh, cibé acu atá sé faoi mhaoirseacht nó gan mhaoirseacht agus is cuma cé mhéad nó cé chomh beag ama fisiciúil atá ag gach tuismitheoir. Is féidir le co-chaomhnóireacht fhisiceach cur síos a dhéanamh freisin ar roinnt comhionann ama leis na páistí, rud a thugtar air go coitianta mar roinn 50/50 de chaomhnóireacht fhisiceach.
Mar shampla, is foirmeacha comhchustaim fisiciúla iad caomhnóireacht phríomhúil agus an dara caomhnóireacht fisiciúil toisc go bhfuil am ag gach tuismitheoir leis na páistí.
Nuair nach mbíonn sciar comhionann ama fisiciúil ag na tuismitheoirí leis na páistí, tá príomhocht fisiciúil ag an tuismitheoir a bhfuil níos mó ama fisiciúil aige agus tá príomhocht fisiciúil tánaisteach ag an tuismitheoir eile i bhfoirm cuairte. Mar shampla, nuair nach mbíonn na páistí ag tuismitheoir amháin ach gach deireadh seachtaine eile, tá cúram fisiciúil thánaisteach ag an tuismitheoir seo i bhfoirm cuairte. Tá príomhoideacht fisiciúil na leanaí ag an tuismitheoir eile.
Más mian leat do shocrú coimeád fisiciúil ar leith a phlé nó conas é a athrú, is féidir leat glaoch ar 919-576-7550 chun comhairliúchán a chur in áirithe le ceann dár ndlíodóirí dlí teaghlaigh. Tá gach cás uathúil agus tá sé tábhachtach labhairt le dlíodóir faoi na fíricí atá sonrach do do chás aonair.
Seiceáil ar ais an tseachtain seo chugainn le haghaidh míniú ar chaomhnóireacht dhlíthiúil.


Pronunciation: (rē"pri-zent'), [key]
to present again or anew.
Pronunciation: (rep"ri-zent'), [key]
1. to serve to express, designate, stand for, or denote, as a word, symbol, or the like does; symbolize: In this painting the cat represents evil and the bird, good.
2. to express or designate by some term, character, symbol, or the like: to represent musical sounds by notes.
3. to stand or act in the place of, as a substitute, proxy, or agent does: He represents the company in Boston.
4. to speak and act for by delegated authority: to represent one's government in a foreign country.
5. to act for or in behalf of (a constituency, state, etc.) by deputed right in exercising a voice in legislation or government: He represents Chicago's third Congressional district.
6. to portray or depict; present the likeness of, as a picture does: The painting represents him as a man 22 years old.
7. to present or picture to the mind.
8. to present in words; set forth; describe; state.
9. to set forth or describe as having a particular character (usually fol. by as, to be, etc.): The article represented the dictator as a benevolent despot.
10. to set forth clearly or earnestly with a view to influencing opinion or action or making protest.
11. to present, produce, or perform, as on a stage.
12. to impersonate, as in acting.
13. to serve as an example or specimen of; exemplify: a genus represented by two species.
14. to be the equivalent of; correspond to: The llama of the New World represents the camel of the Old World.
1. to protest; make representations against.
2. Slang.to use or display a secret handshake, sign, gesture, etc., for purposes of identification: The gang members always represent when they see one another.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.

Pronunciation: (rē"pri-zent'), [clé]
chun a chur i láthair arís nó ar an nua.
Pronunciation: (rep"ri-zent'), [tá]
1. a bheith ina léiriú, mar a dhéanann focal, siombail nó rud eile den chineál sin; siombail a dhéanamh: Sa phictiúr seo léiríonn an cat an olc agus an éan an dea-cháil.
2. a léiriú nó a ainmniú le téarma, carachtar, siombail, nó a leithéidí: fuaimeanna ceoil a léiriú le nótaí.
3. seasamh nó gníomhú in áit, mar ionad, proxy, nó gníomhaire a dhéanann: Léiríonn sé an chuideachta i Boston.
4. labhairt agus gníomhú thar ceann údarás tarmligthe: ionadaíocht a dhéanamh ar a rialtas i dtír choigríche.
5. gníomhú ar son nó thar ceann (ionadaí, stáit, etc.) trí cheart ionadaíoch a bheith aige guth a fheidhmiú i reachtaíocht nó rialtas: Léiríonn sé an tríú ceantar Comhdhála i Chicago.
6. a léiriú nó a léiriú; an chuma a chur i láthair, mar a dhéanann pictiúr: Léiríonn an pictiúr é mar fhear 22 bliana d'aois.
7. chun íomhá nó pictiúr a chur i láthair don intinn.
8. a chur i láthair i bhfocail; a chur i láthair; cur síos a dhéanamh; rá.
9. a chur amach nó a thuairisciú mar a bhfuil carachtar ar leith aige (de ghnáth fol. ag mar, a bheith, etc. ): Léiríodh an t-alt an dictóir mar dhíspeir mhaith.
10. a bheith ag cur in iúl go soiléir nó go fírinneach d'fhonn tionchar a imirt ar thuairim nó ar ghníomh nó agóid a dhéanamh.
11. a chur i láthair, a tháirgeadh, nó a fheidhmiú, mar atá ar an stáitse.
12. a bheith ina impersonator, mar atá i ngníomhú.
13. a bheith mar shampla nó mar speiceas de; a chur i láthair: gínse a léirítear le dhá speiceas.
14. a bheith coibhéiseach le; comhoiriúnach le: Léiríonn lama an Domhain Nua camall an Sean Domhain.
1. agóid a dhéanamh; agóidí a dhéanamh ina choinne.
2. Seachadadh. Slang.to use or display a secret handshake, sign, gesture, etc., for purposes of identification: Déanann baill an ghrúpa ionadaíocht i gcónaí nuair a fheiceann siad a chéile.
Random House Unabridged Dictionary, Copyright © 1997, ag Random House, Inc., ar Infoplease.


Septoria leaf spot is the Septoria lycopersici fungus. This common disease attacks tomato plants in addition to cannabis, eggplant, and potatoes. Septoria spreads rapidly, weakens plants, and prevents fruit from reaching maturity. Septoria leaf spot fungal spores hide until the conditions are ideal. The fungus lives in weeds and debris from plants in the soil, spreading with wind and water.
Septoria will travel until finding ideal conditions, then access the plant from the soil. The most favorable conditions for the development of septoria leaf spot are damp, warm areas with temperatures between 60- and 80-degrees Fahrenheit. The first symptom is circular spots appearing on older leaves, usually on the undersides and toward the base of your plant.
The spots are approximately 1/8th to 1/16th of an inch in diameter with tan or light gray centers and a deep brown margin. As Septoria leaf spot progresses, the spots increase in size and often merge. Under magnification, the fungus resembles deep brown pimples. Despite generally appearing on older leaves, Septoria can also develop during every stage of the life of your plant.
If you leave Septoria leaf spot untreated – for instance – on a tomato plant, the leaves will eventually yellow, become dry and fall off. Your plant will be weakened and begin to decline, with the exposed tomatoes becoming susceptible to scalding from the sun. Once the leaves are gone, your plant will be unable to produce mature tomatoes. Septoria leaf spot will advance extremely quickly.
How to Prevent Septoria Leaf Spot
- Clean the area of any diseased plants and debris to help prevent Septoria leaf spot.
- Overwatering your plants will help the disease spread.
- Leave space between your plants to ensure good air circulation.
- Use mulch to stop Septoria leaf spot spores in the soil from reaching the lower leaves.
How to Treat Septoria Leaf Spot
All infected leaves must be removed immediately. Always wash your hands and clean any tools thoroughly before touching your healthy plants. Organic fungicides containing potassium or copper bicarbonate are an effective treatment provided the Septoria leaf spot is not too far advanced. Chemical treatments are not recommended since you may not be able to eat your tomatoes. If you are treating cannabis plants, remove and destroy the infected lower leaves.
If your cannabis plants are flowering, removing the leaves will weaken your plant and negatively impact bud quality. You can improve the circulation in your grow room by adding more fans. Make certain there is space between your plants. To treat Septoria leaf spot on cannabis, all bushy sections of your plant should be trimmed. The leaves should not touch the other plants.
If your plants are outdoors, elevating them slightly will improve air circulation. Septoria leaf spot spores germinate and spread with excess moisture. Keep your soil moist but not wet. Rake outdoor soil for the removal of infected vegetation. The most common hosts of Septoria leaf spot spores are horsenettle and nightshade. Any weeds potentially hosting the disease need to be removed.
Septoria leaf spot thrives in wet, hot conditions. Decrease the humidity level and temperature in your growing space.
Does Septoria Infect Seeds?
Yes, Septoria leaf spot spores can infect your seeds.
What Tomato Varieties Resist Both Septoria Leaf Spot and Early Blight?
You can look for hybrid tomato plants grown to have resistance to septoria leaf spot. The labels on the plants should have the letter S shown after the name of the tomato variety. According to a publication of the Clemson Cooperative Extension, Tomato Diseases and Disorders, there are two plant varieties that exhibit resistance to Septoria leaf spot. They are Jasper hybrid, which is a cherry tomato, and Iron Lady hybrid.
Clemson lists 17 varieties, including Jasper and Iron Lady, that are also resistant to early blight. Some seed vendors use the letter code EB to designate early blight resistance; others use AB. Keep in mind that resistance does not mean immunity.

Is é an spot duille Septoria an seampúis Septoria lycopersici. Bíonn an galar coitianta seo ag dul i gcion ar phlandaí trátaí chomh maith le cannabas, eggplant, agus prátaí. Scaiptear Septoria go tapa, lagú plandaí, agus cosc a chur ar torthaí a bhaint amach aibíocht. Spóirí fungas spot duille Septoria i bhfolach go dtí go mbeidh na coinníollacha oiriúnach. Tá an fungas ina chónaí i bhfál agus i scriosanna ó phlandaí sa ithir, agus scaiptear é leis an ghaoth agus leis an uisce.
Beidh Septoria taisteal go dtí go bhfaighidh sé coinníollacha idéalach, ansin rochtain ar an gléasra ón ithir. Is iad na coinníollacha is fabhraí do fhorbairt septoria leaf spot ná ceantair taise, te le teocht idir 60 agus 80 céim Fahrenheit. Is é an chéad tsiombail ná spotaí ciorclacha a thagann ar duilleoga níos sine, de ghnáth ar an taobh thíos agus i dtreo bun do phlanda.
Tá na spotaí thart ar 1/8 go 1/16 de orlach ar trastomhas le lárionad tan nó liath-ghrá agus imeall donn domhain. De réir mar a théann an spota duille Septoria ar aghaidh, méadaíonn na spotaí i méid agus is minic a chumascann siad. Faoi mhéadaíocht, is cosúil le pimples broine domhain an fongus. Cé go mbíonn sé le feiceáil de ghnáth ar duilleoga níos sine, is féidir le Septoria forbairt le linn gach céim de shaol do phlanda.
Má fhágann tú spot duille Septoria gan chóireáil  mar shampla  ar phlanda trátaí, beidh na duilleoga buí, tiubh agus titim amach. Beidh do phlanda lag agus tosaíonn sé ag titim, agus beidh na trátaí nochtaithe ag éirí so-ghabhálach do scalding ón ngrian. Nuair a bheidh na duilleoga imithe, ní bheidh do phlanda in ann tomátaí aibí a tháirgeadh. Septoria spot duilleach a chur chun cinn go han-tapa.
Conas an Plé Fhéile Septoria a Chosc
- glan an limistéar ó aon phlandaí agus scriosanna galar chun cabhrú le spot duille Septoria a chosc.
- Cabhróidh ró-uisce a chur ar do phlandaí leis an ghalair a scaipeadh.
- Fág spás idir do phlandaí chun dea-shruthú aeir a chinntiú.
- Úsáid mulch chun stop a chur le spóranna liathróid Septoria sa ithir ó shroich na duilleoga níos ísle.
Conas a dhéileáil le Septoria Leaf Spot
Ní mór na duilleoga atá ionfhabhtaithe go léir a bhaint láithreach. Nigh do lámha i gcónaí agus glan gach uirlis go maith sula ndéanann tú teagmháil le do phlandaí sláintiúla. Is cóireáil éifeachtach iad fungicides orgánacha ina bhfuil potaisiam nó bicarbónáit copar ar choinníoll nach bhfuil an spota duille Septoria ró-fhorbartha. Ní mholtar cóireálacha ceimiceacha ós rud é nach féidir leat do thomátaí a ithe. Má tá tú ag cóireáil plandaí cannabais, bain agus scrios na duilleoga íseal atá ionfhabhtaithe.
Má tá do phlandaí cannabais ag bláthú, lagóidh an duilleog a bhaint do phlanda agus beidh tionchar diúltach aige ar cháilíocht na mbróga. Is féidir leat an scaipeadh i do sheomra fáis a fheabhsú trí níos mó lucht leanúna a chur leis. Bí cinnte go bhfuil spás idir do phlandaí. Chun an seipteoraí duilleach a chóireáil ar channabis, ba cheart gach cuid bushy de do phlanda a ghearradh. Níor chóir go gcuirfeadh na duilleoga i dteagmháil leis na plandaí eile.
Má tá do phlandaí amuigh faoin aer, cuirfidh a ardú beagán aer a chur ar an aer. Spóirí spot duille Septoria a gheimhríonn agus a scaipeann le taise iomarcach. Coinnigh do thalamh taise ach gan a bheith fliuch. Tá an t-ábhar a úsáidtear chun an t-ábhar a scriosadh. Is iad na hóstach is coitianta de spóirí spotaí duille Septoria ná horsenettle agus nightshade. Ní mór aon luibheanna a d'fhéadfadh a bheith ina gcuairteoirí ar an ghalair a bhaint.
Fásann spot duille Septoria i gcoinníollacha fliuch, te. Laghdaigh an leibhéal taise agus an teocht i do spás fáis.
An ndéanann Septoria Infection Síolta?
Sea, is féidir le spóirí liathróid Septoria do shíolta a ionfhabhtuithe.
Cad iad na cineálacha trátaí a sheasann in aghaidh an Septoria Leaf Spot agus an Early Blight?
Is féidir leat breathnú ar phlandaí tomato hibrideacha a d'fhás go bhfuil friotaíocht acu i gcoinne spot duille septoria. Ba cheart an litir S a thaispeáint ar lipéid na bplandaí tar éis ainm an chineálacha trátaí. De réir foilseachán de chuid Clemson Cooperative Extension, Tomato Diseases and Disorders, tá dhá chineál plandaí ann a léiríonn friotaíocht i gcoinne spúnóg duille Septoria. Tá siad hibrideach Jasper, a bhfuil trátaí cherry, agus hibrideach Iron Lady.
Liostaíonn Clemson 17 cineálacha, lena n-áirítear Jasper agus Iron Lady, atá frithsheasmhach freisin i gcoinne an bhréag luath. Baineann roinnt díoltóirí síolta úsáid as an gcód litreacha EB chun friotaíocht luath a ainmniú; úsáideann daoine eile AB. Coinnigh i gcuimhne nach gciallóidh frithsheasmhacht an fhrithsheasmhacht.


Cataracts are the opacification or loss of lens transparency that leads to progressive loss of vision. The lens is a totally transparent and lentil-shaped organ located inside the eyeball just behind the iris.
Symptoms of cataracts vary. Vision becomes blurred and the patient sees as if looking through fog. Discomfort with sunlight, changes in color vision, difficulty driving at night and double vision are issues that may occur with cataracts. Depending on the degree and location of the cataract, vision can be almost normal or it can cause almost total blindness (only sees and locates light). When a cataract is total, the ophthalmologist cannot assess the condition of the retina and optic nerve before surgery and must resort to special examinations (ultrasonography, electroretinography).

Is éard atá i cataract ná opacification nó caillteanas trédhearcachta na lionsa a fhágann go gcailltear an radharc de réir a chéile. Is orgán trédhearcach go hiomlán é an lionsa agus tá sé ar chuma lionsa atá suite taobh istigh den bhall súl díreach taobh thiar den iris.
Tá comharthaí cataract éagsúil. Tá an radharc ag dul in olcas agus feiceann an t-othar amhail is dá mba rud é go bhfuil sé ag féachaint trí bhlaosc. Is fadhbanna iad míchompord le solas na gréine, athruithe ar radharc dathanna, deacracht ag tiomáint san oíche agus dearcadh dúbailte a d'fhéadfadh tarlú le cataract. Ag brath ar chéim agus ar shuíomh an catarachta, d'fhéadfadh an radharc a bheith beagnach gnáth nó d'fhéadfadh sé a bheith ina chúis le dalltas beagnach iomlán (ní fheiceann agus ní aimsiúann sé ach solas). Nuair a bhíonn cataract iomlán, ní féidir leis an octalmólóg staid an retina agus an nerve optic a mheas roimh an máinliacht agus ní mór dó dul i ngleic le scrúduithe speisialta (ultrasonography, electroretinography).


This work is the magnum opus of Irish genealogy, a vast and prodigious compendium of family history and source material. The first volume explores the origin and stem of the Irish nation. The old Irish genealogies assembled here are brought down to the lineal descendant of each family living at the time of the British dispossession, although many of the descents are brought down to the 19th century. Also included is a lengthy appendix with an extraordinarily detailed table showing families that owned land in the 12th century. In addition, there is an index of several thousand surnames.
The first half of Volume II consists of Anglo-Irish genealogies, all carried down at least to the Commonwealth period, and most to the last quarter of the 19th century. Arranged alphabetically by family name, these hundreds of genealogies are heavily annotated, and being supported by references to events of comparatively recent history, they sometimes trace the line of descent to an American branch of the family. There also is data on the Huguenot and Palatine families of Ireland and a chapter on the Ulster Plantation and Scots settlers. The latter half of Volume II is encyclopedic in coverage, bearing reference to countless persons, places, and events associated with Ireland.

Is é an saothar seo an magnum opus de shliocht na hÉireann, comhthéacs ollmhór agus iontach de stair teaghlaigh agus ábhar foinse. Sa chéad bhall, déantar iniúchadh ar bhunús agus bunús náisiún na hÉireann. Tá na sean-ginealóga Éireannacha a bailíodh anseo curtha síos go dtí sliocht líneach gach teaghlaigh a bhí ina gcónaí tráth na dífhostaíochta na Breataine, cé go bhfuil go leor de na sliocht curtha síos go dtí an 19ú haois. Tá forlíonadh fada ann freisin le tábla an-fhiosrach a léiríonn teaghlaigh a raibh talamh acu sa 12ú haois. Ina theannta sin, tá innéacs ann ina bhfuil roinnt míle sloinne.
Is éard atá sa chéad leath de Leibhéal II ná ginealaigh Angla-Éireannach, a tugadh síos go dtí tréimhse an Chomhnaidhm ar a laghad, agus an chuid is mó go dtí an ceathrú cuid dheireanach den 19ú haois. Arna socrú go aibítreach de réir ainm teaghlaigh, tá na céadta ginealaigh seo annotated go mór, agus á dtacaíocht acu le tagairtí d'imeachtaí stair réasúnta le déanaí, déanann siad uaireanta líne an shliocht a rianú go brainse Mheiriceá den teaghlach. Tá sonraí ann freisin maidir le teaghlaigh na nUigínot agus na Palatine in Éirinn agus caibidil maidir le Plantation Ulster agus le lonnaitheoirí na hAlban. Tá leath deireanach an Chuid II ar eolas go forleathan, ag tagairt do dhaoine, áiteanna agus imeachtaí gan áireamh a bhaineann le hÉirinn.


I am sure you would agree that modern, high-speed, commercial jet aircraft have figuratively shrunken the globe. In recent years, relatively vast new areas of the earth have been scrutinized by students of the physical and natural sciences. Our colleagues, the virologists, report almost monthly new discoveries such as the Whataroa virus, a new arbovirus isolated in New Zealand, the chikungunya virus, Kyasanur Forest disease, and a host of other unpronounceable agents, diseases, and locations. Yet, we in tropical medicine are not making many really striking discoveries. It may be that parasitologists, having started several hundred years earlier and being more adventuresome, exhausted the field long before the jet era.
In preparation for this Presidential Address, I have studied maps and charts in the hope of discovering a little-known geographic location with a little-known parasite or disease about which I could speak with authority or from experience.

Táim cinnte go n-aontódh tú go bhfuil an domhan ag titim ar an mbonn trí na haerárthaí tráchtála nua-aimseartha, ardluais. Le blianta beaga anuas, tá réimsí réasúnta leathan nua den domhan curtha i scrúdú ag mic léinn na heolaíochta fisiceach agus nádúrtha. Tuairiscíonn ár gcomhghleacaithe, na víreasaithe, fionnachtana nua beagnach gach mí cosúil le víreas Whataroa, arbovírus nua a leithligh sa Nua-Shéalainn, víreas chikungunya, galar Foraois Kyasanur, agus slua eile de ghníomhairí, galair, agus áiteanna nach féidir a fhocal. Ach, ní bhíonn mórán fionnachtana fíor-iontach á ndéanamh againn sa leigheas trópaiceach. B'fhéidir go raibh na paraisítológaithe, a thosaigh roinnt céadta bliain roimhe sin agus a bhí níos eachtrannach, ag baint úsáide as an réimse fada roimh ré an ré eitilte.
Agus mé ag ullmhú don Aistriúchán Uachtaránachta seo, rinne mé staidéar ar léarscáileanna agus ar chairteanna agus súil agam go bhfaighidh mé amach áit gheografach nach bhfuil mórán eolais air le paraisítí nó galair nach bhfuil mórán eolais orthu a bhféadfainn labhairt fúthu le húdarás nó ó thaithí.


#SaveTheMonkeys: Crowd raises funds online to rescue rare primate
The endangered yellow-tailed woolly monkey just got some help thanks to a global effort.
Yellow-tailed woolly monkeys are some of the rarest monkeys in the world. Indeed, one of the few places on Earth to spot them is in Peru.
In one particular area – El Toro, Peru – the monkeys' habitat is constantly under threat from those who want to turn it into farmland. But what if someone could purchase the forest and set aside the land as a nature reserve for the monkeys?
That's exactly what a bunch of conservation-minded people from around the world just did. An organization called This Is My Earth (TIME) recently launched with one goal in mind: crowdsource funds to purchase lands to protect their ecosystems and turn them into nature reserves. People vote for the hotspot they want to help the most, and the ones with the most votes are bought and handed over to local environmental groups to turn into parks and sanctuaries. The yellow-tailed woolly monkeys' habitat was the group's first funded project.
"Rather than lapse into resignation about the state of the planet, we have all made a statement that we can do better," said Dr. Uri Shanas, TIME's co-founder and a professor of conservation biology at the University of Haifa in Israel. "Humans may have made our share of environmental problems, but we can also solve them!"
The collaborative effort involves the participation of scientists, environmentalists and leaders from around the world, including China, Kenya, Israel, the United Kingdom and the United States.
"Our goal is to significantly broaden international participation in protecting lands located in the most precious biodiversity hotspots on earth," said Shanas. "By providing a democratic platform for citizens of the world to act and influence decision making via the single most important conservation management tool, preserving land and biodiversity, our new organization can help lead global conservation into a new era."
In its effort to save the yellow-tailed woolly monkey, the organization is helping an animal that has been listed as one of the world's 25 most endangered primates. The group joins the British nonprofit Neotropical Primate Conservation, which is developing eco-tourism initiatives to build awareness of the Peruvian monkey population and its habitat.
The Israel-based TIME joins others from the Mediterranean country that are helping with wildlife protection. In recent months, we profiled Ofir Drori, who is helping arrest Africa's worst wildlife traffickers, as well as a veterinarian named Yaron Schmid who is photographing endangered animals to bring more awareness to their cause.
While the Peruvian land is being purchased, TIME is already looking toward its next project. "By spring, we hope to have some new spots for you to vote on," Shanas said. "It feels good to be engaged in something real we can do together."
MORE FROM THE GRAPEVINE:

#SaveTheMonkeys: Tá slua ag bailiú cistí ar líne chun primate neamhchoitianta a shábháil
Fuair an t-aingeal uachtar buí buí atá i mbaol géarchéime cabhair díreach a bhuíochas le hiarracht dhomhanda.
Tá na maoineacha uachtar-béal-giollach ar na maoineacha is annamh ar domhan. Go deimhin, tá ceann de na háiteanna ar domhan chun iad a fheiceáil i bPéiru.
I limistéar áirithe  El Toro, Peiriú  tá gnáthóg na mhoncaí faoi bhagairt i gcónaí ó dhaoine atá ag iarraidh é a thiontú ina talamh feirme. Ach cad a tharlaíonn má fhéadann duine éigin an foraoise a cheannach agus an talamh a chur ar leataobh mar chúlchiste nádúrtha do na maoine?
Sin go díreach a rinne grúpa daoine a bhfuil a ndúchas ar an gcothabháil acu ó gach cearn den domhan. Bunaíodh eagraíocht ar a dtugtar This Is My Earth (TIME) le déanaí le sprioc amháin i gcuimhne: cistí a bhailiú chun talún a cheannach chun a n-éiceachórais a chosaint agus iad a thiontú ina gcosáin nádúrtha. Vótálann daoine don phointe is fearr a theastaíonn uathu a chabhrú, agus ceannaítear na cinn a bhfuil an líon is mó vótaí acu agus cuirtear ar láimh iad do ghrúpaí comhshaoil áitiúla chun iad a thiontú i bpáirceanna agus i gconarthaí. Ba é an t-áit chónaithe na mbeacáin uachtar buí-eireaball an chéad tionscadal maoinithe a bhí ag an ngrúpa.
"Seachas a bheith ag éirí as a chéile faoi staid na pláinéad, tá ráiteas déanta againn go léir gur féidir linn níos fearr a dhéanamh", a dúirt an Dr. Uri Shanas, comhbhunaitheoir TIME agus ollamh bitheolaíochta caomhnaithe in Ollscoil Haifa in Iosrael. "B'fhéidir gur chuir daoine an chuid is mó de na fadhbanna comhshaoil ar fáil dúinn, ach is féidir linn iad a réiteach freisin!"
Tá rannpháirtíocht eolaithe, comhshaoil agus ceannairí ó gach cearn den domhan sa iarracht chomhoibritheach, lena n-áirítear an tSín, an Cheanáin, Iosrael, an Ríocht Aontaithe agus na Stáit Aontaithe.
"Is é ár gcuspóir rannpháirtíocht idirnáisiúnta a leathnú go suntasach i gcosaint talún atá suite sna hotspots bithéagsúlachta is luachmhaire ar domhan", a dúirt Shanas. "De réir a sholáthar ardán daonlathach do shaoránaigh an domhain chun gníomhú agus tionchar a imirt ar chinntí a dhéanamh trí an uirlis bainistíochta caomhnaithe is tábhachtaí amháin, ag caomhnú talún agus bithéagsúlacht, is féidir lenár n-eagraíocht nua cabhrú le caomhnú domhanda a threorú isteach in ré nua".
I a chuid iarrachtaí an t-aingeal uachtar buí buí a shábháil, tá an eagraíocht ag cabhrú le hainmhí a liostaíodh mar cheann de na 25 primate is mó atá i mbaol a bheith ar an domhan. Tá an grúpa ag dul i dteagmháil leis an eagraíocht neamhbhrabúis Neotropical Primate Conservation, atá ag forbairt tionscnaimh éicea-turaisimh chun feasacht a thógáil ar phobal na mhoncaí Peirú agus a gnáthóg.
Tá TIME atá lonnaithe in Iosrael ag dul i dteannta daoine eile ó thír Mheánmhuirí atá ag cabhrú le cosaint na fiadhúlra. Le míonna beaga anuas, rinneamar próifíl ar Ofir Drori, atá ag cabhrú le hiondúirí fiadhúlra fiadhúlra is measa san Afraic a ghabháil, chomh maith le tréidirear Yaron Schmid a bhfuil grianghraf á thógáil aige d'ainmhithe atá i mbaol chun níos mó feasachta a thabhairt dá gcúis.
Cé go bhfuil an talamh Peirúis á cheannach, tá TIME ag féachaint cheana féin ar a chéad tionscadal eile. "Ar an earrach, tá súil againn go mbeidh roinnt spotaí nua agat le vótáil", a dúirt Shanas. "Is maith an mothúchán a bheith i mbun rud éigin fíor is féidir linn a dhéanamh le chéile".
MÁIRE ÓN GRAPEVINE:


Hairy circle of spheres
Well hairy isn’t too accurate unless there are hairs that are closed circles, but these are the concessions one makes for a dumb play on the Hairy Sphere Theorem. This post doesn’t really have much to do with that theorem.
What’s below are some pictures suggesting Seifert fibrations of S^1 x S^2, the circle of spheres. View this 3-manifold as an interval of concentric spheres where you have to imagine gluing the inner sphere to the outer sphere.
A Seifert fibration of a 3-manifold is a filling of the 3-manifold with circles so that around each point a teeny tiny enough chunk looks like it’s filled with parallel lines. Here these circles get chopped into intervals. The interval going through the north pole connects up to give one circle, and so does the interval through the south pole. We call these circles the singular fibers.
All the other intervals connect up with a fixed number of others to form circles. These are the regular fibers. Near each point on a singular fiber, a regular fiber passes by some fixed number of times, the order of the singular fiber. In the picture above this number is 5 for both singular fibers.
In the three examples above, red fibers are shown at regularly spaced latitudes (along fixed longitudes) going from the north pole to the south pole. The yellow fibers are copies rotated to other longitudes.
Let’s look at just the red ones as the orders of the singular fibers increase.
Neat, I guess.
While we’re here. Have some eye candy. There’s more in this set.
(Oh, and these pictures are a result of experimenting with Grasshopper for Rhino and some non-photorealistic rendering.)

Cearcall gruaige de spéir
Bhuel hairy nach bhfuil an-chruinn mura bhfuil gruaigí atá ciorcail dúnta, ach tá na tabhartasan a dhéanann duine le haghaidh cluiche dúr ar an Theorema Sféar Hairy. Níl mórán a dhéanamh ag an bpost seo leis an teoirím sin.
Seo thíos roinnt pictiúir a thugann le tuiscint go bhfuil snáithíní Seifert de S ^ 1 x S ^ 2, ciorcal na sféar. Féach ar an 3-manifold seo mar eagar de spheres comhchruinnithe ina bhfuil tú a shamhlú gluing an sphere inmheánach leis an sphere seachtrach.
Is é fíobhríocht Seifert de 3-manifold líonadh an 3-manifold le ciorcail ionas go mbeidh timpeall gach pointe chunk beag go leor beag cosúil go bhfuil sé líonta comhthreomhar. Anseo, ghearrtar na ciorcail seo ina n-eachtraí. An t-eachtra ag dul tríd an póil thuaidh nascadh suas chun a thabhairt ar chiorcal amháin, agus mar sin a dhéanann an t-eachtra tríd an póil theas. Glaoimid na ciorcail seo ar na snáithíní singil.
Nascann na hidirthréimhsí eile go léir le líon seasta daoine eile chun ciorcail a chruthú. Is iad seo na snáithíní rialta. In aice le gach pointe ar shnáithín aonair, téann snáithín rialta trí roinnt líon seasta uaireanta, ord an shnáithín aonair. Sa phictiúr thuas tá an uimhir seo 5 do na snáithíní singil.
Sna trí shampla thuas, léirítear snáithíní dearga ag leitheadtaí réadacha (thaobh le fadachtaí seasta) ag dul ón póil thuaidh go dtí an póil theas. Is cóipeanna iad na snáithíní buí a rothlú go fadtéarmacha eile.
Déanaimis breathnú ar na cinn dearga amháin de réir mar a mhéadaíonn orduithe na snáithíní singil.
Ceart, is dócha.
Cé go bhfuil muid anseo. Tóg roinnt candy súl. Tá níos mó sa tsraith seo.
(Ó, agus is é seo na pictiúir mar thoradh ar thriail le Grasshopper do Rhino agus roinnt neamh-photorealistic a thabhairt.)


Aeolian processes at the Mars Exploration Rover Meridiani Planum landing site
The martian surface is a natural laboratory for testing our understanding of the physics of aeolian (wind-related) processes in an environment different from that of Earth. Martian surface markings and atmospheric opacity are time-variable, indicating that fine particles at the surface are mobilized regularly by wind. Regolith (unconsolidated surface material) at the Mars Exploration Rover Opportunity's landing site has been affected greatly by wind, which has created and reoriented bedforms, sorted grains, and eroded bedrock. Aeolian features here preserve a unique record of changing wind direction and wind strength. Here we present an in situ examination of a martian bright wind streak, which provides evidence consistent with a previously proposed formational model for such features. We also show that a widely used criterion for distinguishing between aeolian saltation- and suspension-dominated grain behaviour is different on Mars, and that estimated wind friction speeds between 2 and 3 m s⁻¹, most recently from the northwest, are associated with recent global dust storms, providing ground truth for climate model predictions.

Próisis aeolacha ag an suíomh tuirlingthe Rover Exploration Mars Meridiani Planum
Is saotharlann nádúrtha é dromchla na Márta chun ár dtuiscint ar fhisice próisis aeolacha (a bhaineann le gaoth) a thástáil i dtimpeallacht atá difriúil ó thimpeallacht na Talún. Tá marcálacha dromchla na Máirse agus opacity atmaisféar ag athrú ama, ag léiriú go gcuirtear cáithníní bheaga ar an dromchla ar siúl go rialta ag gaoth. Tá tionchar mór ag an ghaoth ar Regolith (ábhar dromchla neamhchomhshlánaithe) ag suíomh tuirlingthe an Mars Exploration Rover Opportunity, a chruthaigh agus a ath-eagrú foirmeacha leaba, gráin shocraithe, agus bunchloch éadithe. Coinníonn gnéithe aeolacha anseo taifead uathúil ar threo agus neart gaoithe a athrú. Anseo cuirimid scrúdú in situ ar shraith gaoithe geal Martian, a sholáthraíonn fianaise atá ag teacht le samhail foirmithe a mholadh roimhe seo do shaintréithe den sórt sin. Taispeánann muid freisin go bhfuil critéar a úsáidtear go forleathan chun idirdhealú a dhéanamh idir iompar gráin saltation- agus fionraí-dominated aeolian difriúil ar Mars, agus go bhfuil luasanna frithghníomh gaoithe measta idir 2 agus 3 m s-1, le déanaí ó thuaidh, bainteach le stoirmeacha deannaigh dhomhanda le déanaí, ag soláthar fírinne talún do thuargas samhlacha aeráide.


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Electronic Noses are devices able to generate digital maps of complex odors. Their working principles are aimed at reproducing the human olfactive system. The sensitivity of these artificial
sensors, in fact, is comparable to that of human olfactive receptors; their data processing is similar to the sensing events occurring inside the olfactive bulbs and the resulting odor
classification is carried out by Neural Networks or Statistic Multi-Component Analysis which reproduce both the learning and identification mechanisms of the cortical neurons.
In the Microelectronics and Microsystems Institute Laboratories of the National Research Council (Rome, Lecce and Bologna Departments) several different prototypes of artificial olfactive
systems have been set up since few years. These systems are based on chemical sensors, which work as miniaturized transducers, reacting selectively and reversibly to volatile chemicals and
generating electrical signals as a function of substance concentrations. The devices set up in the Rome Department, in collaboration with the Electronic Engineering and Chemistry Departments of
University of “Tor Vergata”, were based on piezoelectrical sensors, i.e. mass sensors. They are placed inside the “nostril” (measuring chamber) of the nose (LibraNose and EnQbe). The sorption
of volatile molecules on the sensing layer (Me-Tetraphenylporphyrins differently derivatized and deposited) determines a frequency shift in crystal oscillations related to mass increase of the
quartz (Thickness Shear Mode Resonators). In the devices assembled in Lecce and Bologna Departments, chemical interactions induce electron transfers between the semiconductor surface and gas
molecules adsorbed thereon, which results in variations of their conductivity (Metal Oxide Semiconductor). Specifically, these variations are consequent to the volatile compound oxidation
occurring at semiconductor surface and to reduction of Oxygen molecules previously adsorbed on the sensor surface (SnO2, In2O3, TiO2…). The features common to all the prototypes are: a
prompt response to chemical interactions and the absence of time consuming sample pretreatment. Research in the three Departments were differently focused on minimizing the size of the
equipment (by using microtechnologies) and improving both electronics, softwares and chemical features of sensors.
These purposes are achieved by setting up new materials able to increase the resolution (ppb) towards analytes, to decrease the response time, to obtain a complete reversibility, accuracy and
reproducibility in measurements, and finally to get a high output signal with respect to noise. The setting up of such machines may have several powerful applications. In foodstuff
manufacturing they may be used to assess the food real quality (e.g. evaluation of foodstuff preservation, control of marks guaranteeing the quality and origin of food products, fraud and food
adulteration preventions …), in environment monitoring (exhausted gas; gas, aromatic idrocarbons and aerosols leakages …), in medicines (diagnostic tool for skin, endocrin system,
gastrointestinal and lung apparatus diseases, etc.

Is gléasanna iad na Noses Leictreonacha atá in ann léarscáileanna digiteacha d'aird casta a ghiniúint. Tá a bprionsabail oibre dírithe ar chóras olfachta an duine a athdhéanamh. Tá an íogaireacht na n-
Tá an t-ábhar a fhaightear ó na braiteoirí, i ndáiríre, inchomparáide le braiteoirí olfachta an duine; tá a phróiseáil sonraí cosúil leis na himeachtaí braite a tharlaíonn taobh istigh de na bolbha olfachtacha agus an boladh a eascraíonn
Déantar an aicmiú trí Líonraí Nearacha nó Anailís Il-Choimhthionscanta Staidrimh a athdhéanann meicníochtaí foghlama agus sainaitheanta na néaróin cortical araon.
I saotharlanna Institiúid Micreileictreonaic agus Micreascriostaí an Chomhairle Náisiúnta Taighde (Róm, Lecce agus Roinn Bologna) rinneadh roinnt prototaipí éagsúla de
Tá córais curtha ar bun le cúpla bliain anuas. Tá na córais seo bunaithe ar shensóirí ceimiceacha, a oibríonn mar thrasduitheoirí mion-
comharthaí leictreacha a ghiniúint mar fheidhm de thiúchan substaintí. Na feistí a bunaíodh i Roinn na Róimhe, i gcomhar le Rannóg Innealtóireachta Leictreonacha agus Rannóg Cheimic na hOllscoile
Bhí an t-eispéireas seo bunaithe ar shensóirí píosaithe leictreacha, i.e. braiteoirí mais. Cuirtear iad taobh istigh de nostril (camra tomhais) an srón (LibraNose agus EnQbe). An sorption
Is é an t-athrú a tharlaíonn i gcúrsaí an chréatúir a bhaineann le hairíonna a bheith ag teacht le chéile i gcúrsaí an chréatúir a bhaineann le hairíonna a bheith ag teacht le chéile i gcúrsaí an chréatúir.
"Chlárú" a bhaineann le "chomhshruthú" a bhaineann le "chomhshruthú" a bhaineann le "chomhshruthú" a bhaineann le "chomhshruthú". Sna feistí a chuirtear le chéile i dTríoireanna Lecce agus Bologna, cuireann idirghníomhaíochtaí ceimiceacha aistrithe leictreon idir dromchla an leathsheoltóra agus an gáis
Tá sé de phribhléid ag an bhfoirm seo go bhfuil sé in ann a bheith ag baint úsáide as an bhfoirm seo le haghaidh a gcuid comhábhair, mar shampla, an t-amhrán, an t-amhrán, an t-amhrán, an t-amhrán, an t-amhrán, an t-amhrán, an t-amhrán. Go sonrach, is é an toradh atá ar na hathruithe seo ná ocsaídiú na gcomhdhúile éadrom
Tá an t-ábhar a úsáidtear chun an t-ábhar a scriosadh agus an t-ábhar a scriosadh le haghaidh an t-ábhar a scriosadh. Is iad na gnéithe a bhíonn i gcoitinne ag na fréamhshamhlacha go léir ná:
Freagra tapa ar idirghníomhaíochtaí ceimiceacha agus gan réamhchóireáil sampla a thógann am. Bhí taighde sna trí Roinn dírithe ar bhealach difriúil ar mhéid na
Tá sé de chuspóir ag an gCoimisiún, le linn na tréimhse sin, an t-iarracht a dhéanamh ar an méid seo a leanas:
Baintear na cuspóirí sin amach trí ábhair nua a chur ar bun ar féidir leo an réiteach (ppb) i leith anailít a mhéadú, an t-am freagartha a laghdú, aisghabhálacht iomlán, cruinneas agus
Tá an t-ábhar seo le feiceáil i bhfianaise na n-athnuachana a dhéantar ar an mbonn. D'fhéadfadh go mbeadh roinnt feidhmchlár cumhachtach ag bunú meaisíní den sórt sin. I dtáirgí bia
Is féidir iad a úsáid chun measúnú a dhéanamh ar an gcáilíocht iarbhír bia (m.sh. Measúnú ar chaomhnú bia, rialú ar mharcanna a ráthaíonn cáilíocht agus tionscnamh táirgí bia, calaois agus bia
cosc a chur ar mhíchumas ...), i monatóireacht an chomhshaoil (gás scagtha; gáis, hidreacarbóin aramacha agus sceitheadh aeróisóil ...), i gcógas (uirlis dhiagnóiseach don chraiceann, córas endocrine,
galair den aparáid gastrointestinal agus na scamhóg, etc.


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Birch is a broadleaved deciduous hardwood tree of the genus Betula (//), in the family Betulaceae, which also includes alders, hazels, and hornbeams, and is closely related to the beech/oak family, Fagaceae. The genus Betula contains 30 to 60 known taxa of which 11 are on the IUCN 2011 Red List of Threatened Species. They are typically rather short-lived pioneer species widespread in the Northern Hemisphere, particularly in northern temperate and boreal climates. This tree is sometimes called "The Watchful Tree" because of eye-like impressions on the bark.
The common name birch comes from Old English birce, bierce, from Proto-Germanic *berk-jōn (cf. German Birke, West Frisian bjirk), an adjectival formation from *berkōn (cf. Dutch berk, Low German Bark, Norwegian bjørk), itself from the Proto-Indo-European root *bʰerHǵ- ~ bʰrHǵ-, which also gave Lithuanian béržas, Ukrainian beréza, Albanian bredh ‘fir’, Ossetian bærz(æ), Sanskrit bhurja, Polish brzoza, Latin fraxinus ‘ash (tree)’. This root is presumably derived from *bʰreh₁ǵ- ‘to shine’, in reference to the birch's white bark. The Proto-Germanic rune berkanan is named after the birch.
Birch species are generally small to medium-sized trees or shrubs, mostly of temperate climates. The simple leaves are alternate, singly or doubly serrate, feather-veined, petiolate and stipulate. They often appear in pairs, but these pairs are really borne on spur-like, two-leaved, lateral branchlets. The fruit is a small samara, although the wings may be obscure in some species. They differ from the alders (Alnus, other genus in the family) in that the female catkins are not woody and disintegrate at maturity, falling apart to release the seeds, unlike the woody, cone-like female alder catkins.
The bark of all birches is characteristically marked with long, horizontal lenticels, and often separates into thin, papery plates, especially upon the paper birch. It is resistant to decay, due to the resinous oil it contains. Its decided color gives the common names gray, white, black, silver and yellow birch to different species.
The buds form early and are full grown by midsummer, all are lateral, no terminal bud is formed; the branch is prolonged by the upper lateral bud. The wood of all the species is close-grained with satiny texture, and capable of taking a fine polish; its fuel value is fair.
Flower and fruit
The flowers are monoecious, opening with or before the leaves and borne once fully grown these leaves are usually 3–6 millimetres (0.12–0.24 in) long on three-flowered clusters in the axils of the scales of drooping or erect catkins or aments. Staminate aments are pendulous, clustered or solitary in the axils of the last leaves of the branch of the year or near the ends of the short lateral branchlets of the year. They form in early autumn and remain rigid during the winter. The scales of the staminate aments when mature are broadly ovate, rounded, yellow or orange color below the middle, dark chestnut brown at apex. Each scale bears two bractlets and three sterile flowers, each flower consisting of a sessile, membranaceous, usually two-lobed, calyx. Each calyx bears four short filaments with one-celled anthers or strictly, two filaments divided into two branches, each bearing a half-anther. Anther cells open longitudinally. The pistillate aments are erect or pendulous, solitary; terminal on the two-leaved lateral spur-like branchlets of the year. The pistillate scales are oblong-ovate, three-lobed, pale yellow green often tinged with red, becoming brown at maturity. These scales bear two or three fertile flowers, each flower consisting of a naked ovary. The ovary is compressed, two-celled, and crowned with two slender styles; the ovule is solitary.
Birches often form even-aged stands on light, well-drained, particularly acidic soils. They are regarded as pioneer species, rapidly colonising open ground especially in secondary successional sequences following a disturbance or fire. Birches are early tree species to establish in primary successions, and can become a threat to heathland if the seedlings and saplings are not suppressed by grazing or periodic burning. Birches are generally lowland species, but some species, such as Betula nana, have a montane distribution. In the British Isles, there is some difference between the environments of Betula pendula and Betula pubescens, and some hybridization, though both are "opportunists in steady-state woodland systems". Mycorrhizal fungi, including sheathing (ecto)myccorhizas, are found in some cases to be beneficial to tree growth.
- Betula albosinensis—Chinese red birch (northern + central China)
- Betula alnoides—alder-leaf birch (China, Himalayas, northern Indochina)
- Betula ashburneri (Bhutan, Tibet, Sichuan, Yunnan Provinces in China)
- Betula baschkirica (eastern European Russia)
- Betula bomiensis (Tibet)
- Betula calcicola (Sichuan + Yunnan Provinces in China)
- Betula celtiberica (Spain)
- Betula chichibuensis (Chichibu region of Japan)
- Betula chinensis—Chinese dwarf birch (China, Korea)
- Betula coriaceifolia (Uzbekistan)
- Betula corylifolia (Honshu Island in Japan)
- Betula costata (northeastern China, Korea, Primorye region of Russia)
- Betula cylindrostachya (Himalayas, southern China, Myanmar)
- Betula dahurica (eastern Siberia, Russian Far East, northeastern China, Mongolia, Korea, Japan)
- Betula delavayi - (Tibet, southern China)
- Betula ermanii—Erman's birch (eastern Siberia, Russian Far East, northeastern China, Korea, Japan)
- Betula falcata (Tajikistan)
- Betula fargesii (Chongqing + Hubei Provinces in China)
- Betula fruticosa (eastern Siberia, Russian Far East, northeastern China, Mongolia, Korea, Japan)
- Betula globispica (Honshu Island in Japan)
- Betula gmelinii (Siberia, Mongolia, northeastern China, Korea, Hokkaido Island in Japan)
- Betula grossa—Japanese cherry birch (Japan)
- Betula gynoterminalis (Yunnan Province in China)
- Betula honanensis - (Henan Province in China)
- Betula humilis or Betula kamtschatica— Kamchatka birch platyphylla (northern + central Europe, Siberia, Kazakhstan, Xinjiana, Mongolia, Korea)
- Betula insignis - (southern China)
- Betula karagandensis (Kazakhstan)
- Betula klokovii (Ukraine)
- Betula kotulae (Ukraine)
- Betula litvinovii (Turkey, Iran, Caucasus)
- Betula luminifera (China)
- Betula maximowiczii—monarch birch (Japan, Kuril Islands)
- Betula medwediewii—Caucasian birch (Turkey, Iran, Caucasus)
- Betula megrelica (Republic of Georgia)
- Betula microphylla (Siberia, Mongolia, Xinjiang, Kazakhstan, Kyrgyzstan, Uzbekistan)
- Betula nana—dwarf birch (northern + central Europe, Russia, Siberia, Greenland, Northwest Territories of Canada))
- Betula pendula—silver birch (widespread in Europe and northern Asia; Morocco; naturalized in New Zealand and scattered locations in US + Canada)
- Betula platyphylla (Betula pendula var. platyphylla)—Siberian silver birch (Siberia, Russian Far East, Manchuria, Korea, Japan, Alaska, western Canada)
- Betula potamophila (Tajikistan)
- Betula potaninii (southern China)
- Betula psammophila (Kazakhstan)
- Betula pubescens—downy birch, also known as white, European white or hairy birch (Europe, Siberia, Greenland, Newfoundland; naturalized in scattered locations in US)
- Betula raddeana (Caucasus)
- Betula saksarensis (Khakassiya region of Siberia)
- Betula saviczii (Kazakhstan)
- Betula schmidtii (northeastern China, Korea, Japan, Primorye region of Russia)
- Betula sunanensis (Gansu Province of China)
- Betula szechuanica (Betula pendula var. szechuanica)—Sichuan birch (Tibet, southern China)
- Betula tianshanica (Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, Xinjiang, Mongolia)
- Betula utilis—Himalayan birch (Afghanistan, Central Asia, China, China, Tibet, Himalayas)
- Betula wuyiensis (Fujian Province of China)
- Betula zinserlingii (Kyrgyzstan)
Note: many American texts have B. pendula and B. pubescens confused, though they are distinct species with different chromosome numbers.
- Birches native to North America include
- Betula alleghaniensis—yellow birch (B. lutea) (eastern Canada, Great Lakes, Northeastern US, Appalachians)
- Betula cordifolia—mountain paper birch (eastern Canada, Great Lakes, Northeastern US)
- Betula glandulosa—American dwarf birch (Siberia, Mongolia, Russian Far East, Alaska, Canada, Greenland, mountains of western US and New England, Aridondacks)
- Betula lenta—sweet birch, cherry birch, or black birch (Quebec, Ontario, eastern US)
- Betula michauxii—Newfoundland dwarf birch (Newfoundland, Labrador, Quebec, Nova Scotia)
- Betula minor—dwarf white birch (eastern Canada, mountains of northern New England and Adirondacks)
- Betula nana—dwarf birch or bog birch (also in northern Europe and Asia)
- Betula nigra—river birch or black birch (eastern US)
- Betula occidentalis—water birch or red birch (B. fontinalis) (Alaska, Yukon, Northwest Territories, western Canada, western US)
- Betula papyrifera—paper birch, canoe birch or American white birch (Alaska, most of Canada, northern US)
- Betula populifolia—gray birch (eastern Canada, northeastern US)
- Betula pumila—swamp birch (Alaska, Canada, northern US)
Due to the hardness of Birch, it is better to shape it with power tools, as it is quite difficult to work it with hand tools.
- Birch wood is fine-grained and pale in colour, often with an attractive satin-like sheen. Ripple figuring may occur, increasing the value of the timber for veneer and furniture-making. The highly decorative Masur (or Karelian) birch, from Betula verrucosa var. carelica, has ripple textures combined with attractive dark streaks and lines. Birch wood is suitable for veneer, and birch plywood is among the strongest and most dimensionally stable plywoods, although it is unsuitable for exterior use.
- Birch plywood is made from laminations of birch veneer. It is light but strong, and has many other good properties. Birch plywood is used to make longboards (skateboard), giving it a strong yet flexible ride. It is also used (often in very thin grades with many laminations) for making model aircraft.
- Extracts of birch are used for flavoring or leather oil, and in cosmetics such as soap or shampoo. In the past, commercial oil of wintergreen (methyl salicylate) was made from the sweet birch (Betula lenta).
- Birch-tar or Russian oil extracted from birch bark is thermoplastic and waterproof; it was used as a glue on, for example, arrows, and also for medicinal purposes.
- Fragrant twigs of silver birch are used in saunas to relax the muscles.
- Birch is also associated with the feast of Pentecost in Germany, Central and Eastern Europe, and Russia, where its branches are used as decoration for churches and homes on this day.
- Birch leaves are used to make a diuretic tea and extracts for dyes and cosmetics.
- Ground birch bark, fermented in sea water, is used for seasoning the woolen, hemp or linen sails and hemp rope of traditional Norwegian boats.
- Birch twigs bound in a bundle, also called birch, were used for birching, a form of corporal punishment.
- Many of the indians of North America prized the birch for its bark, which due to its light weight, flexibility, and the ease with which it could be stripped from fallen trees, was often used for the construction of strong, waterproof but lightweight canoes, bowls, and wigwams.
- The Hughes H-4 Hercules was made mostly of birch wood, despite its better-known moniker, "The Spruce Goose".
- Birch plywood was specified by the BBC as the only wood that can be used in making the cabinets of the long-lived LS3/5A loudspeaker.
- Birch is used as firewood due to its high calorific value per unit weight and unit volume. It burns well, without popping, even when frozen and freshly hewn. The bark will burn very well even when wet because of the oils it contains. With care, it can be split into very thin sheets that will ignite from even the smallest of sparks.
- Birch sap is a traditional drink in Northern Europe, Russia, and Northern China. The sap is also bottled and sold commercially. Birch sap can be used to make birch syrup, which is used like maple syrup for pancakes and waffles. Birch wood can be used to smoke foods.
- Birch seeds are used as leaf litter in miniature terrain models.
- "Birch flowers" is the English marketing name for the catkins of the Broussonetia luzonica tree. Known in the Philippines as himbabao or alukon, these flowers are commonly used in the cuisine of northeastern Luzon. However, despite their English name and the similar appearance of their flowers, B. luzonica is not in any way related to the birch tree.
- Birch oil is used in the manufacture of Russia leather, a water-resistant leather.
- Birch bark is high in betulin and betulinic acid, phytochemicals which have potential as pharmaceuticals, and other chemicals which show promise as industrial lubricants.
- Birch buds are used in folk medicine.
- Birch bark can be soaked until moist in water, and then formed into a cast for a broken arm.
- The inner bark of birch can be ingested safely.
- In northern latitudes, birch is considered to be the most important allergenic tree pollen, with an estimated 15–20% of hay fever sufferers sensitive to birch pollen grains. The major allergen is a protein called Bet v I.
Wood pulp made from birch gives relatively long and slender fibres for a hardwood. The thin walls cause the fibre to collapse upon drying, giving a paper with low bulk and low opacity. The birch fibres are, however, easily fibrillated and give about 75% of the tensile strength of softwood[clarification needed]. The low opacity makes it suitable for making glassine.
In India, the birch (Sanskrit: भुर्ज, bhurja) holds great historical significance in the culture of North India, where the thin bark coming off in winter was extensively used as writing paper. Birch paper (Sanskrit: भुर्ज पत्र, bhurja patra) is exceptionally durable and was the material used for many ancient Indian texts. The Roman period Vindolanda tablets also use birch as a material on which to write and birch bark was used widely in ancient Russia as note paper (beresta) and for decorative purposes and even making footwear.
Baltic birch is among the most sought-after wood in the manufacture of speaker cabinets. Birch has a natural resonance that peaks in the high and low frequencies, which are also the hardest for speakers to reproduce. This resonance compensates for the roll-off of low and high frequencies in the speakers, and evens the tone. Birch is known for having "natural EQ". http://www.soundonsound.com/sos/1996_articles/feb96/eq.html
Drums are often made from birch. Prior to the 1970s, it was one of the most popular drum woods. Because of the need for greater volume and midrange clarity, drums were made almost entirely from maple until recently[clarification needed], when advances in live sound reinforcement and drum microphones have allowed the use of birch in high-volume situations. Birch drums have a natural boost in the high and low frequencies, which allows the drums to sound fuller.
Birch wood is sometimes used as a tonewood for semiacoustic and acoustic guitar bodies, and occasionally for solid-body guitar bodies. It is also a common material used in mallets for keyboard percussion.
- Birches have spiritual importance in several religions, both modern and historical.
- In Celtic cultures, the birch symbolises growth, renewal, stability, initiation and adaptability. The birch is highly adaptive and able to sustain harsh conditions with casual indifference. Proof of this adaptability is seen in its easy and eager ability to repopulate areas damaged by forest fires or clearings.
- The Czech word for the month of March, Březen, is derived from the Czech word bříza meaning birch, as birch trees flower in March under local conditions.
- They are also associated with the Tír na nÓg, the land of the dead and the Sidhe, in Gaelic folklore, and as such frequently appear in Scottish, Irish, and English folksongs and ballads in association with death, or fairies, or returning from the grave.
- It is also New Hampshire's state tree.
- Robert Frost, an American poet, pays homage to the act of climbing birch trees in one of his more famous poems, "Birches."
- In the Swedish city of Umeå, the silver birch tree has a special place. In 1888, the Umeå city fire spread all over the city and nearly burnt it down to the ground, but some birches, supposedly, halted the spread of the fire. To protect the city against future fires, it was decided to plant silver birch trees all over the city. Umeå later adopted the unofficial name of "City of the Birches (Björkarnas stad)". Also, the ice hockey team of Umeå is called Björklöven, translated to English "The Birch Leaves".
- National Tree of Finland and Russia.
- The leaves of the silver birch tree are used in the festival of St George, held in Novosej and other villages in Albania.
- Sunset Western Garden Book, 1995:606–607
- Ashburner, K. & McAllister, H.A. (2013). The genus Betula: a taxonomic revision of birches: 1-431. Royal Botanic Gardens, Kew.
- Keeler, Harriet L. (1900). Our Native Trees and How to Identify Them. New York: Charles Scriber's Sons. pp. 295–297.
- Birches. (A Symposium, Royal Botanic Garden, Edinburgh 24–26 September 1982. Proceedings of the Royal Society of Edinburgh, 85B, 1–11, 1984.
- "Birch". Wood Magazine. Retrieved December 1, 2013.
- "Birch Tar – How to collect it". Archived from the original on February 27, 2008.
- Prakel, David (August 1979). "BBC's Home Service", Hi-Fi Answers, pp67–9 (Courtesy link)
- Joyce, Daniel. "Birch Seed Leaves". reapermini.com.
- Grygus, Andrew. "Alokon". Clove Garden.
- White Birch – American Cancer Society (cancer.org)
- William Arthur Clark (January 1, 1937). "History of Fracture Treatment Up to the Sixteenth Century". The Journal of Bone & Joint Surgery (Needham, MA, USA: The Journal of Bone & Joint Surgery, Inc.) 19 (1): 61–62.
Another method cited was that of splints made of birch bark soaked in water until quite soft. They were then carefully fitted to the limb and tied with bark thongs. On drying, they became stiff and firm. There is no record of the use of extension, but, nevertheless, very few crippled and deformed Indians were to be seen.
- Nanko, Hiroki; Button, Alan; Hillman, Dave (2005). The World of Market Pulp. USA: WOMP, LLC. pp. 192–195. ISBN 0-615-13013-5.
- Sanjukta Gupta, "Lakṣmī Tantra: A Pāñcarātra Text", Brill Archive, 1972, ISBN 90-04-03419-6. Snippet:... the text recommends that the bark of the Himalayan birch tree (bhurja-patra) should be used for scribbling mantras ...
- Amalananda Ghosh, "An Encyclopaedia of Indian Archaeology", BRILL, 1990, ISBN 90-04-09264-1. Snippet:... Bhurja-patra, the inner bark on the birch tree grown in the Himalayan region, was a very common writing material ...
- "Traditional celebrations in Novosej". RASP. Retrieved August 28, 2013.
- Flora of North America: Betula
- Flora of China: Betula
- Grimshaw, John (2009). New Trees, Recent introductions to cultivation. Kew Publishing, RBG Kew. pp. 163–174.
|Wikimedia Commons has media related to Betula.|
|Wikispecies has information related to: Betula|
- Tree Family Betulaceae Diagnostic photos of many species, Morton Arboretum specimens
- Eichhorn, Markus (July 2010). "The Birch Tree". Test Tube. Brady Haran for the University of Nottingham.

 Teastaíonn luacha breise don alt seo chun a fhíorú. (Samhain 2008)
Is crann cruach chladach leathan é an Birch den ghéineas Betula (//), sa teaghlach Betulaceae, lena n-áirítear alders, hazel, agus hornbeams, agus tá baint dlúth aige leis an teaghlach beech / oak, Fagaceae . Tá 30 go 60 tacsa ar eolas sa ghéineas Betula, agus tá 11 acu ar Liosta Dearg Speiceas IUCN 2011. Is speiceas pionóireachta iad de ghnáth a bhfuil saol gairid acu agus atá forleathan san Iarsféar Thuaidh, go háirithe i gclimaí measartha agus bhóireacha thuaidh. Uaireanta tugtar "An Crann Fágála" ar an gcrann seo mar gheall ar na léitheoireachtaí atá cosúil le súile ar an gcor.
Tagann an t-ainm coiteann birch ó Birce, bierce, ón bprótho-Ghearmáinis * berk-jōn (cf. Gearmáinis Birke, West Frisian bjirk), foirmiú aidiachtúil ó *berkōn (cf. Bairc na hÍsiltíre, Barc na Gearmáine Íseal, Bjørk na hIorua), é féin ó bhunfhocal Próta-Ind-Eorpach *bherH- ~ bhrH-, a thug béržas Liotuáineach, beréza Úcránach, bredh Albannach fir, bærz(æ Osséiteach), bhurja Sanscrait, brzoza Polainnis, fraxinus Laidineach ash (crann) . Is dócha go dtagann an fréamh seo ó * bhreh1-  to shine, i dtaca le craiceann bán an birch. Ainmnítear an rún Próta-Ghearmáinis berkanan tar éis an birch.
Is arbhair nó cnaipí beaga go meánmhéide iad speicis Birch, go príomha i gclimaí measartha. Tá na duilleoga simplí malartacha, singil nó dúbailte, feather-veined, petiolate agus stipulate. Is minic a bhíonn siad le chéile, ach is ar bhrainseacha taobh, dhá-leafed, cosúil le spórlaí a bhíonn na páirteanna seo i ndáiríre. Is samára beag é an toradh, cé go bhféadfadh na sciatháin a bheith dodhéanta i roinnt speiceas. Tá difríocht idir na catagóirí agus na catagóirí eile (Alnus, seánra eile sa teaghlach) toisc nach bhfuil na catagóirí baineann adhmaid agus nach ndéanann siad dífhilleadh nuair a bhíonn siad aibí, ag titim as a chéile chun na síolta a scaoileadh, murab ionann agus na catagóirí baineann adhmaid, cónach cosúil leis na catagóirí baineann.
Tá craiceann gach birch marcáilte go tréithúil le lenticels fada, cothrománach, agus is minic a scarann sé i bplátaí tanaí páipéir, go háirithe ar an birch páipéir. Tá sé resistant do sceitheadh, mar gheall ar an ola resinous ina bhfuil sé. Tugann a dath cinneadh na hainmneacha coitianta bocht, bán, dubh, airgid agus buí birch do speicis éagsúla.
Tá na buachaillí go luath agus tá siad lánfhásta faoi lár an tsamhraidh, tá siad go léir taobh, níl aon buachaill deiridh déanta; tá an brainse fadaithe ag an buachaill taobh uachtarach. Tá adhmad na speiceas go léir dlúth-ghranáilte le téacs satin, agus in ann glanadh fíneáil a dhéanamh; tá a luach breosla cothrom.
Blóg agus torthaí
Tá na bláthanna monoecious, ag oscailt leis na duilleoga nó roimh na duilleoga agus a dhéantar nuair a bhíonn na duilleoga seo tar éis fás go hiomlán de ghnáth 36 miliméadar (0.120.24 in) ar fhad ar ghluasraí trí bhláthanna i n-aistritheoirí na scamaí de catkins nó aments droim nó seasta. Tá amantaí staminataí pendulous, clustered nó solitary in axils na duilleoga deireanach de bhrainse na bliana nó in aice le foircinn na mbrainse gearr taobh de bhrainse na bliana. Forbraíonn siad go luath san earrach agus fanann siad rigid i rith an gheimhridh. Tá scálaí na n-amant staminate nuair a bhíonn siad aibí go forleathan uibheach, cruinn, buí nó oráiste thíos sa lár, donn castain dorcha ag an mbarr. Tá dhá brachtle agus trí bhláthanna steiriliúla ag gach scála, agus tá calyx seisiúil, membranaceous, de ghnáth dhá-lobed, ag gach bláth. Tá ceithre shreangán gearr ag gach calyx le anthers aon-chill nó go docht, dhá shreangán roinnte ina dhá ghrainm, gach ceann acu ag leath-anthers. Osclaíonn cealla anther go lonracha. Tá na pistillate aments in airde nó pendulous, aonair; críochnaithe ar na brainseanna cosúil le spór taobh dhá-leafed na bliana. Tá na scamaill pistillate forleithne-oifásach, trí-lobed, buí-ghorm éadrom go minic tinted le dearg, ag éirí donn ag aibíocht. Tá dhá nó trí bhláth úllmhaire ag na scamaill seo, agus tá uibhealach nocht ag gach bláth. Tá an ovary comhbhrúite, dhá chealla, agus coróinithe le dhá stíleanna tanaí; tá an ovule ina aonar.
Is minic a bhíonn birches ag teacht suas go cothrom ar ithir shoiléir, dea-dhraenáilte, go háirithe aigéadach. Meastar gur speiceas ceannródaíoch iad, ag coilíneáil talamh oscailte go tapa go háirithe i sraitheanna iarchéime darach tar éis cur isteach nó tine. Is speiceas crainn iad na birches a bunaítear go luath i gcúinsí príomhúla, agus is féidir leo a bheith ina bhagairt ar an bhfithis mura gcuirtear na síolta agus na seabhacáin faoi chois trí phásaíocht nó dóiteán tréimhsiúil. Is speiceas ísealchríocha iad birches de ghnáth, ach tá dáileadh montane ag roinnt speiceas, mar shampla Betula nana. Sna hOileáin Bhreataine, tá roinnt difríochta idir timpeallachtaí Betula pendula agus Betula pubescens, agus roinnt hibridiú, cé go bhfuil an dá cheann "deiseanna i gcórais choille chobhsaíochta seasmhach". Tá fungais mhicóiríseacha, lena n-áirítear micreathrú (ecto) micreathrú, le fáil i gcásanna áirithe chun a bheith tairbheach do fhás crann.
- Betula albosinensisBéirín dearg na Síne (an Tuaisceart + lár na Síne)
- Beirce (An tSín, na Himalaigh, an t-iarthair Indáine)
- Betula ashburneri (Bhutan, Tibet, Sichuan, Yunnan Provinces sa tSín)
- Betula baschkirica (an Rúis Oirtheorpach)
- Betula bomiensis (Tibet)
- Betula calcicola (Phróifísigh Sichuan + Yunnan sa tSín)
- Betula celtiberica (an Spáinn)
- Betula chichibuensis (réigiún Chichibu na Seapáine)
- Betula chinensisBéirge dwarf Sínis (an tSín, an Chóiré)
- Betula coriaceifolia (Uisbéiceastáin)
- Betula corylifolia (Oileán Honshu sa tSeapáin)
- Betula costata (nord-oirthear na Síne, an Chóiré, réigiún Primorye na Rúise)
- Betula cylindrostachya (Himalaigh, an tSín theas, Mianma)
- Betula dahurica (Oirthear na Sibéir, an Fhear-Oirthear na Rúise, an t-Oirthear Thuaidh na Síne, Mhongóil, an Chóiré, an tSeapáin)
- Betula delavayi - (Tibet, deisceart na Síne)
- Betula ermaniiBéirín Erman (Oirthear na Sibéir, an Fhear-Oirthear na Rúise, an tSeoirtheisceart na Síne, an Chóiré, an tSeapáin)
- Betula falcata (Táidicistan)
- Betula fargesii (Chongqing + Hubei Provinces sa tSín)
- Betula fruticosa (Oirthear na Sibéir, an Fhear-Oirthear na Rúise, an t-Oirthear Thuaidh na Síne, Mhongóil, an Chóiré, an tSeapáin)
- Betula globispica (Oileán Honshu sa tSeapáin)
- Betula gmelinii (Sibiria, Mhongóil, an tSín thuaidh-os-thuaidh, an Chóiré, Oileán Hokkaido sa tSeapáin)
- Betula grossaBéirch ceirise na Seapáine (an tSeapáin)
- Betula gynoterminalis (Phróificsin Yunnan sa tSín)
- Betula honanensis - (Phróificsin Henan sa tSín)
- Betula humilis nó Betula kamtschatica Kamchatka birch platyphylla (an Eoraip thuaidh + lárnach, an tSibéir, an Chasacstáin, an Xinjiana, an Mhongóil, an Chóiré)
- Betula insignis - (theas na Síne)
- Betula karagandensis (Casaicstáin)
- Betula klokovii (an Úcráin)
- Betula kotulae (an Úcráin)
- Betula litvinovii (an Tuirc, an Iaráin, an Chócaisc)
- Betula luminifera (an tSín)
- Beithín monarca Betula maximowiczii (an tSeapáin, Oileáin na Kuril)
- Betula medwediewii Birch Caucasian (an Tuirc, an Iaráin, an Caucasus)
- Betula megrelica (Phoblacht na Gréige)
- Betula microphylla (Sibéir, Mhongóil, Xinjiang, an Chasacstáin, an Chirgíseachtan, an Úisbéiceastáin)
- Beirín beag-dhuanach Betula (an Eoraip thuaidh agus lárnach, an Rúis, an tSibéir, an Ghraonlainn, Ceantair Thuaisceart Cheanada)
- Betula pendula silver birch (a bhfuil scaipeadh go forleathan san Eoraip agus i dtuaisceart na hÁise; Maracó; a nádúróchadh sa Nua-Shéalainn agus áiteanna scaipthe sna Stáit Aontaithe agus i gCeanada)
- Betula platyphylla (Betula pendula var. (Siberia, Far East na Rúise, Manchuria, Korea, an tSeapáin, Alaska, iarthar Cheanada)
- Betula potamophila (Táidicistan)
- Betula potaninii (deisceart na Síne)
- Betula psammophila (Casaicstáin)
- Beirce bán, Beirce bán na hEorpa nó Beirce gruaige (an Eoraip, an tSibéir, an Ghraonlainn, Nua-Thír Thír; a nádúrófar in áiteanna scaipthe sna Stáit Aontaithe)
- Betula raddeana (Caucasus)
- Betula saksarensis (réigiún Khakassiya na Sibéir)
- Betula saviczii (Casaicstáin)
- Betula schmidtii (nord-oirthear na Síne, an Chóiré, an tSeapáin, réigiún Primorye na Rúise)
- Betula sunanensis (Ghearnóg Gansu na Síne)
- Betula szechuanica (Betula pendula var. Sechuanica)  Sichuan birch (Tibet, deisceart na Síne)
- Betula tianshanica (Casaicstáin, Cairgisstáin, Taidsícstáin, Úisbéiceastáin, Xinjiang, Mhongóil)
- Betula utilis Birch Himalayan (Afganastáin, Lár na hÁise, an tSín, an tSín, an Tíobht, na Himalaigh)
- Betula wuyiensis (Phoibríochta Fujian na Síne)
- Betula zinserlingii (an Chirgíse)
Tabhair faoi deara: tá B. pendula agus B. pubescens mearbhall i go leor téacsanna Meiriceánacha, cé gur speiceas ar leith iad le huimhreacha crómasóim éagsúla.
- Cuimsíonn birches dúchasacha i Meiriceá Thuaidh
- Betula alleghaniensis (B. lutea) (Oirthear Cheanada, na Lochlanna Móra, Oirthear Thuaisceart na SA, na hAppalacha)
- Betula cordifolia  birch páipéar sléibhe (an Ceanada thoir, na Lochlanna Móra, Oirthear na SA)
- Betula glandulosaBéirge dwarf Meiriceánach (Sibéir, Mhongóil, an Fhar-Oirthear na Rúise, Alasca, Ceanada, an Ghraonlainn, sléibhte an iarthar na SA agus Shasana Nua, Aridondacks)
- Betula lenta birch milis, birch criosach, nó birch dubh (Quebec, Ontario, oirthear na SA)
- Betula michauxiiBéirín dwarf Newfoundland (Newfoundland, Labrador, Québec, Nova Scotia)
- Beirce bán bán (an Ceanada thoir, sléibhte thuaidh na Sasana Nua agus Adirondacks)
- Beirge beag-dhuanacha Betula nó beirge bog (san Eoraip Thuaidh agus san Áise freisin)
- Beirce abhainn Betula nigra nó beirce dubh (an taobh thoir de na Stáit Aontaithe)
- Beirce uisce nó beirce dearg (B. fontinalis) (Alaska, Yukon, Ceantair Thuaidh, iarthar Cheanada, iarthar na SA)
- Betula papyrifera birch páipéar, birch canoe nó birch bán Mheiriceá (Alaska, an chuid is mó de Cheanada, i dtuaisceart na SA)
- Betula populifoliabirtín liath (an Ceanada thoir, an Oirthuaisceart na SA)
- Beirce (Alaska, Ceanada, Tuaisceart na SA)
Mar gheall ar chruacht Birch, is fearr é a mhúnlú le huirlisí cumhachta, mar go bhfuil sé deacair é a oibriú le huirlisí láimhe.
- Tá adhmad birch grinn-fhiú agus bán, go minic le glanadh tarraingteach cosúil le satin. D'fhéadfadh go dtarlódh figiúirí ripple, ag méadú luach an adhmaid le haghaidh veneer agus maisiú troscáin. An birch Masur (nó Karelian) an-decorative, ó Betula verrucosa var. Tá an t-ábhar seo leagtha amach i gclár de na táirgí a úsáidtear chun an t-ábhar a chur ar fáil. Tá adhmad birch oiriúnach le haghaidh veneer, agus tá plátach birch i measc na plátaí pláta is láidre agus is cobhsaí ó thaobh na tomhais de, cé nach bhfuil sé oiriúnach le húsáid lasmuigh.
- Déantar plátach Birch ó lámhacha de veneer birch. Tá sé éadrom ach láidir, agus tá go leor airíonna maithe eile aige. Úsáidtear plátach birch chun longboards (skateboard) a dhéanamh, rud a thugann turas láidir ach solúbtha dó. Úsáidtear é freisin (go minic i gcineálacha an-tinn le go leor laminations) chun samhlacha aerárthaí a dhéanamh.
- Úsáidtear sliocht de bhéirce le haghaidh blas nó ola leathair, agus i gcósmála mar sheabán nó seampú. San am atá caite, rinneadh ola tráchtála de gheimhreadh (sailicealait meitile) ón bpíosa milis (Betula lenta).
- Tá an t-ola dearbhtha nó an ola Rúiseach a bhaintear as craiceann an chréachta thermoplastach agus uiscedhíonach; baineadh úsáid as mar ghlue ar, mar shampla, saigheada, agus chun críocha leighis freisin.
- Úsáidtear crainn bhuí de birch airgid i saunaí chun na matáin a scíth a ligean.
- Tá baint ag an bpeirce freisin le féile na Pentecost sa Ghearmáin, i Lár agus in Oirthear na hEorpa, agus sa Rúis, áit a n-úsáidtear a chuid brainsí mar mhaisiú do eaglaisí agus do theachanna an lá seo.
- Úsáidtear duilleoga birch chun tae diuretic agus sliocht a dhéanamh le haghaidh dathanna agus cosmaidí.
- Úsáidtear craiceann birch talún, a fhéimintear in uisce farraige, chun seilíní uachtar, cainb nó líonta agus rópa cainb bhoid traidisiúnta na hIorua a séasúrú.
- Bhí crainn birch ceangailte i búnt, ar a dtugtar birch freisin, a úsáidtear le haghaidh birching, cineál pionós coirp.
- Bhí luach mór ag go leor de na hIndiaigh i Meiriceá Thuaidh ar an mbéirc as a chraiceann, a d'úsáid go minic mar gheall ar a mheáchan éadrom, a solúbthacht, agus an éascaíocht a d'fhéadfaí é a bhaint as crainn thit, chun canoes, boils, agus wigwams láidir, uiscedhíonach ach éadrom a thógáil.
- An Hughes H-4 Hercules a rinneadh den chuid is mó de adhmad birch, in ainneoin a moniker níos fearr ar a dtugtar, "An Spruce Goose".
- Shonraigh an BBC go raibh plátach Birch mar an t-aon adhmad is féidir a úsáid chun caibinéid an labhraí LS3 / 5A fad-saoil a dhéanamh.
- Úsáidtear birch mar fhiodh dóite mar gheall ar a luach calórach ard in aghaidh an aonaid meáchain agus an aonaid toirte. Tá sé ag dóite go maith, gan popping, fiú nuair a reoite agus úr-chlóite. Déanfaidh an craiceann dóite go han-mhaith fiú nuair a bheidh sé fliuch mar gheall ar na olaí atá ann. Le cúram, is féidir é a scoilt i bpáipéir an-tinn a thiocfaidh chun bheith ag lasadh fiú ón sparks is lú.
- Is deoch traidisiúnta é saothra Birch i dTuaisceart na hEorpa, sa Rúis, agus i dTuaisceart na Síne. Déantar an seip a bhuidéil agus a dhíol go tráchtála freisin. Is féidir an t-aiste birch a úsáid chun síoróip birch a dhéanamh, a úsáidtear cosúil le síoróip maple le haghaidh pancóga agus waffles. Is féidir adhmad birch a úsáid chun bianna a chaitheamh.
- Úsáidtear síolta birch mar chréagán duilleoga i múnlaí talún mionleibhéil.
- Is é "Flóirí Birch" an t-ainm margaíochta Béarla do na catkins de chrann Broussonetia luzonica. Ar a dtugtar himbabao nó alukon sna hOileáin Fhilipíneacha, úsáidtear na bláthanna seo go coitianta i gcistin thuaidh Luzon. Mar sin féin, in ainneoin a n-ainm Béarla agus cuma comhchosúil a bhláthanna, níl B. luzonica i dteagmháil ar chor ar bith leis an mbéirc.
- Úsáidtear ola Birch i ndéantúsaíocht leathar na Rúise, leathar atá frithsheasmhach don uisce.
- Tá craiceann birch ard i bétúlín agus aigéad betulinic, fíteachimiceáin a bhfuil acmhainn acu mar chógaisíochta, agus ceimiceáin eile a léiríonn dóchas mar shreamhachtaí tionsclaíocha.
- Úsáidtear buds Birch i leigheas tíre.
- Is féidir craiceann birch a shimpliú go dtí go mbeidh sé taise in uisce, agus ansin a bheith i bhfoirm i gcostas do lámh bhriste.
- Is féidir an craiceann istigh de birch a ingest sábháilte.
- I léirsí thuaidh, meastar go bhfuil an birch ar an pollán crainn ailléirgeanach is tábhachtaí, agus meastar go bhfuil 15-20% de dhaoine atá ag fulaingt ó thitim an fhiabhras íogair do ghráin pollen birch. Is próitéin ar a dtugtar Bet v I an príomh-ailléirgín.
Tugann púpl adhmaid a dhéantar as birch snáithíní réasúnta fada agus tanaí do chrann crua. Mar gheall ar na ballaí tanaí, bíonn an snáithín ag titim nuair a bhíonn sé ag triomú, rud a thugann páipéar le mórcháilíocht íseal agus le neamh-thrédhearcacht íseal. Tá na snáithíní birch, áfach, go héasca fibrillated agus a thabhairt faoi 75% den neart teannadh de adhmad bog. Tá an opacity íseal ann agus is féidir é a úsáid chun glasín a dhéanamh.
Sa India, tá tábhacht mhór stairiúil ag an mbéirc (Sanskrit) i gcultúr na hIndia Thuaidh, áit a raibh an craiceann tanaí a thiteann as sa gheimhreadh in úsáid go forleathan mar pháipéar scríbhneoireachta. Tá páipéar birch (Sanskrit) thar a bheith marthanach agus ba é an t-ábhar a úsáidtear le haghaidh go leor téacsanna ársa na hIndia. Baineadh úsáid as an bpíosaí Vindolanda ón tréimhse Rómhánach freisin mar ábhar ar a raibh scríbhneoireacht agus craiceann bpíosa a úsáidtear go forleathan sa Rúis ársa mar pháipéar nótaí (beresta) agus chun críocha maisiúcháin agus fiú bróga a dhéanamh.
Tá an birch Bhaltach ar cheann de na crainn is mó a bhfuil éileamh orthu i ndéantúsaíocht caibinéid cainteoirí. Tá cumhrán nádúrtha ag Birch a shroicheann an buaicphointe sna minicíochtaí ard agus íseal, agus is iad sin na minicíochtaí is deacra le hathchóirithe ag cainteoirí. Cuireann an réamhrá seo le haghaidh an rollaigh-de na minicíochtaí íseal agus ard sna cainteoirí, agus cuireann sé an t-uimhir in aon dul. Tá a fhios ag Birch go bhfuil "EQ nádúrtha" aige. http://www.soundonsound.com/sos/1996_articles/feb96/eq.html
Is minic a dhéantar drumaí as birch. Roimh na 1970idí, ba é ceann de na coillte tromlach is mó a tóir air. Mar gheall ar an ngá le níos mó toirte agus soiléire lárraon, rinneadh drumaí beagnach go hiomlán ó mhapaill go dtí le déanaí, nuair a cheadaigh dul chun cinn i neartú fuaime beo agus micreafóin drumaí úsáid birch i gcásanna ardtoirte. Tá borradh nádúrtha ag drumaí Birch sna minicíochtaí arda agus íseal, rud a ligeann do na drumaí fuaim níos iomláine a thabhairt.
Uaireanta úsáidtear adhmad birch mar adhmad ton do chomhlachtaí giotár leath-aicmeach agus fuaimeach, agus ó am go ham do chomhlachtaí giotár comhlacht soladach. Is ábhar coitianta é freisin a úsáidtear i mallets le haghaidh buille clasaiceach.
- Tá tábhacht spioradálta ag birches i roinnt reiligiúin, nua-aimseartha agus stairiúla araon.
- I gcultúir Cheilteach, siombailíonn an birch fás, athnuachan, cobhsaíocht, tionscnamh agus oiriúnaitheacht. Tá an birch an-chomhfhorbailte agus in ann a bheith in ann na coinníollacha crua a choimeád ar bun le neamhchinnteacht ócáideach. Léirítear an fhianaise ar an gcumas oiriúnaithe seo ina chumas éasca agus díograiseach chun limistéir a ndearnadh damáiste dóibh le tinte foraoise nó le glanadh foraoise a athshlánú.
- Tagann an focal Seiceach do mhí an Mhárta, Březen, ón bhfocal Seiceach bříza a chiallaíonn birch, mar go bhfuil crainn birch ag bláthú i mí an Mhárta faoi choinníollacha áitiúla.
- Tá baint acu freisin leis an Tír na nÓg, talamh na marbh agus an Sidhe, i dtóir phoiblí na Gaeltachta, agus mar sin feictear iad go minic i amhráin agus i bballaí tíre na hAlban, na hÉireann agus na Breataine i gcomhar le bás, nó le féirí, nó le filleadh ón tuama.
- Is é freisin crann stáit New Hampshire.
- Robert Frost, ina file Meiriceánach, tugann ómós do ghníomh na climbing crann birch i gceann de na dánta is cáiliúla aige, "Birches".
- I gcathair na Sualainne Umeå, tá áit speisialta ag an gcrann birch airgid. Sa bhliain 1888, scaipeadh tine chathair Umeå ar fud na cathrach agus chaill sé beagnach é go dtí an talamh, ach is dócha gur chuir roinnt birches stop le scaipeadh an tine. Chun an chathair a chosaint i gcoinne tine amach anseo, chinntear crainn birch airgid a phlandaí ar fud na cathrach. Ina dhiaidh sin ghlac Umeå an t-ainm neamhoifigiúil "Cath na Birches (Björkarnas stad)". Chomh maith leis sin, tugtar Björklöven ar fhoireann haca oighir Umeå, a aistrítear go Béarla "The Birch Leaves".
- Crann Náisiúnta na Fionlainne agus na Rúise.
- Úsáidtear duilleoga an chrainn birch airgid i féile Naomh Eoghain, a reáchtáiltear i Novosej agus i sráidbhailte eile san Albáin.
- Leabhar Gairdín an Iarthair, 1995: 606  607
- Ashburner, K. & McAllister, H.A. (2013). An ghéineas Betula: athbhreithniú tacsainómach ar bhéircheanna: 1-431. Gairdíní Bótánacha Ríoga, Kew.
- Keeler, Harriet L. (1900). Ár Crann Dúchasach agus Conas iad a Aithint. Nua-Eabhrac: Charles Scriber's Sons. pp. 295297.
- Birches. (A Symposium, Royal Botanic Garden, Edinburgh 24-26 Meán Fómhair 1982. Proceedings of the Royal Society of Edinburgh, 85B, 11 Meán Fómhair 1984.
- "Bird". Iris Wood. Arna óstáil ar 1 Nollaig, 2013.
- "Bird Tar  Conas é a bhailiú". Archaithe ón bhunaidh ar 27 Feabhra, 2008.
- Prakel, David (Lúnasa 1979). "Seirbhís Baile an BBC", Freagraí Hi-Fi, pp679 (Cliceáil le haird)
- Joyce, Daniel. - Tá sé ceart go leor. "Bíoraí Síol Birch". reapermini.com.
- Grygus, Andrew. - Tá sé ceart go leor. "Alokon". Gairdín Clove.
- White Birch  American Cancer Society (cancer.org)
- William Arthur Clark (Eanáir 1, 1937). "Scéal na Cóireála ar Chroí go dtí an Séú haois déag". An Iris um Míchirurgia Cnámh agus Comhpháirteacha (Needham, MA, SAM: The Journal of Bone & Joint Surgery, Inc.) 19 (1): 6162.
Ba é an modh eile a luaitear ná splints a rinneadh de chraiceann birch a bhí curtha i uisce go dtí go raibh siad go leor bog. Ansin, cuireadh na cnámha go cúramach ar an mbéal agus baintear iad le stronganna de chré. Nuair a thriomú, tháinig siad crua agus daingean. Níl aon taifead ann go raibh úsáid á bhaint as an síneadh, ach, mar sin féin, ní raibh ach an-bheagán Indiach criptithe agus míchruinn le feiceáil.
- Nanko, Hiroki; Button, Alan; Hillman, Dave (2005). An Domhan an Phlúthmhargaidh. USA: WOMP, LLC. pp. 192195. ISBN 0-615-13013-5.
- Sanjukta Gupta, "Lakṣmī Tantra: A Pāñcarātra Text", Brill Archive, 1972, ISBN 90-04-03419-6. Snippet:... molann an téacs gur chóir craiceann crann birch Himalayan (bhurja-patra) a úsáid chun mantraí a scribble ...
- Amalananda Ghosh, "Einseiclopóid de Ailtireacht Indiach", BRILL, 1990, ISBN 90-04-09264-1. Snippet:... Bhurja-patra, an craiceann istigh ar an crann birch a fhásann sa réigiún Himalayan, bhí ábhar scríbhneoireachta an-choitianta ...
- "Ceiliúradh traidisiúnta i Novosej". RASP. A fuarthas ar 28 Lúnasa, 2013.
- Flora Mheiriceá Thuaidh: Betula
- Flora na Síne: Betula
- Grimshaw, John (2009). Crann Nua, Tús le feirmeoireacht le déanaí. Foilsitheoir Kew, RBG Kew. pp. 163174.
Tá meáin ag Wikimedia Commons a bhaineann le Betula.
Tá faisnéis ag Wikispecies a bhaineann le: Betula
- Family Tree Betulaceae Grianghraf diagnóiseach de go leor speiceas, speiceas Morton Arboretum
- Eichhorn, Markus (Iúil 2010). "An Crann Birch". Tiúb tástála. Brady Haran d'Ollscoil Nottingham.