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Cdc nhd khoa hgc a Trung Qudc dd ehi tgo ra mot thiet bi mdng nhu t&gidy bdt chudc qud trinh truyin tin hiiu diin hoa hgc trong bd ndo con ngudi.
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AC nha khoa hpc da thidt k l ra thilt bi ban din mang mdng (TFT) d l tai tap khdp ndi giua 2 noron thin kinh, duge xem nhu la mdt khdp thin kinh sinh hpc, ed thi trd thanh mdt thanh phin quan tepng ttong sir phat biln cfla mang thin kinh nhan tao, ddng thdi cd thi ling dung cho mpt loat eac Unh vuc tfl che tao robot den phat triln cdng nghe may tinh.Thilt bi TFT nay la thilt bi mdi nhlt dupc chl tao mdng nhu mdt td gily, cd chflc nang giflp he thd'ng dien tu boat ddng linh hoat, vdi chi phi san xuat thap va than thien vdi mdi trudng hon.
Thilt bi khdp thin kinh nhan tao TFT nay bao gdm chit oxit kem indi (IZO), dl lam ea mdt kdnh din va edng didn cue, dupc ngan bang mdt ldp mang chit diln phan la eac hat nano silic didxit Si02 day khoing 550 nanomet, mang mdng nay duge tap ra nhd phuong phap ling dpng hoi hda hpc.
Thilt k l nay ed dac dilm va chuc nang tuong tu khdp thin kinh sinh hpc - la mdt khe nhd xiu nam giua cae noron thin kinh lien kl ma cac tin hiSu didn va hda hpc dugc truyen qua. Thdng qua eae khdp than kinh nay, eac noron cd thi din ttiiyen cac tin hieu va thdng diep xung quanh nao.
Tit ca cac noron than kinh dS bi kieh thich diSn, va khi bi kich thieh nd s6 tao
ra 'xung diSn' kM cd su thay ddi du ldn vl dien ap cfla eac noron thin kinh.
Nhiing xung dien nay kich hoiit cac tin hiSu thdng qua cae noron thin kinh khiln cac neron thin kinh diu USn bi kich thich giii phdng ra cac hda chit, dugc xem nhu cae ehlt din truyin thin kinh, di qua cac khdp thin kinh.
Tuong tu nhu cac xung dien diu ra nay, cac nha khoa hpc da dua vao diln cue diu tiSn ttong thilt bi eua hp mpt diln ap thIp de khiln eac prptpn - cd chflc nang hoat ddng nhu mdt chit din truyin thin kinh - tu cac mang mdng didxit silie di chuyin hudng tdi keph din
IZO, nam d ddi diSn.
Do cac proton mang diln tieh duong hflt cae electeons mang didn tich am hudng tdi chflng trong kSnh din ,tZO , eho phep ddng dien ttiiyln qua kSnh din, gidng nhu eae tin hieu than kinh thdng thudng.
Khi eang cd nhilu chat din truyen thin kinh dupc truyen qua khdp thin kinh
KCM-2.2014
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THANH TUU Mdn - CdNG HGHE MOI - SAN PHliM M d l
giiia hai noron thin kinh ben ttong nap, cac kit ndi giiia hai noron nay ted nSn manh hon. Co chl boat ddng nay ehinh la nln tang giflp chflng ta cd kha nang hpe tap va ghi nhd mpi thfl. HiSn tugng nay gpi la tinh mem dep cfla khdp thin kinh.
Cae nha khea hpe da phat hiSn thiy ring khi hai dien ap ngin diroe dua vao thilt bi ttong mdt khoang thdi gian ngin, dif n ap thfl hai ed thi kich thich mdt ddng diSn ldn hon ben teong kSnh din ehlt IZO so vdi dien ap thfl nhlt, nhu vay nd 'gU nhd' cae phan flng tfl dien ap thu nhat.
Mdt tae gia hen kit eua nghiSn cflu nay, Qing Wan, trudng Khoa hpc va ky thuat dien tu thude Dai hpc Nam Kinh (Trung Qude) chp bilt: 'Khdp thin kinh mdng nhu td giay nay cd thi dugc su dung dl xay dung cac mang thin kinh nhan tao ed tepng lugng nhe va than thlSn vl mat sinh hpe, ddng thdi vdi uu dilm vl tinh linh hoat va tinh tugng hpp sinh hpc, ed thi cho phep sfl dung dl tao ra eac giao dien sinh vat - eg khi ttong nhieu flng dung sinh h p c '
P.T.T. (TheoPhys.Org,13/2/2014)
OUAIV DIEM MOI VE Dl TRUYEIV O THUC VAT
Cde dgc diim di truyin phiic tgp khdng chi dugc xdc dinh bdi nhifng thay ddi trong cdc chudi ADN. Cdc nhd khoa hgc tit Trung tdm Tin sinh hgc Bgi hgc Groningen (GBIC), cdng vdi cdc ding nghiip ngudi Phdp, dd chira ring nhimg ddu hiiu biiu sinh cd thi dnh hudng din cdc dgc diim nhu thdi gian ra hoa vd cdu tnic ciia thitc vdt.
H
ON nua, nhiing dau hiSu nay dugc truyin qua nhilu thd he mdt each dn dinh. Vdi cae kit qua nghien cflu dugc xuat ban ttSn Tap ehi Science, cd ve nhu vile sfla Iai sach giao khoa di truyin hpc hien da ed co sd.Chung ta dugc day rang ADN la nen tang vat lieu di truyen. Cac gen efla chflng ta dugc bilu diln bing bdn chu cai ndi tilng A, T, C va G eung tao thanh ma di truyin. Su thay ddi cfla mdt chu cai ttong ma nay cd thi lam mdt gen ngCmg hoat ddng hoae boat ddng khdng dflng each.
Thuc t l la boat ddng gen cua chflng ta cflng bi anh hudng bdi eac dau hieu bilu sinh da dugc bilt den trong nhilu thap ky. Vi du, cytosine nucleotide (C teong
Hoa Arabidopsis. Anh: Credit 0 tXivier M. IFoiob
ma di truyin) ed thi ehuyin thinh methyleytosine. Metyl hda cytosine, mdt loai diu bidu bilu sinh, thudng hIn quan den kiem che boat dpng eua gen.
Thua k l bilu sinh
"Trong khi d ddng vat ed vfl, eac dau hilu bilu sinh thudng duge tai thilt lap qua moi thi he, d thiic vat, su tai thilt ISp
28 K C M - 2 7 a u
