Ochungechungeni lwabaseshi namafilimu, lapho izazi zobugebengu zidlala indima enkulu yokushayela itulo, ungabona kaningi ukuthi umuntu oshiye le mikhondo ukhonjwe kanjani ngempumelelo ngesidunu sikagwayi noma ngokuhlafuna ushingamu wanamathela etafuleni. Empilweni yangempela, ungafunda okuningi ngaye ekuhlafuneni ushingamu obekusemlonyeni womuntu. Namuhla sizobheka ucwaningo lapho ososayensi baseNyuvesi yaseCopenhagen bathola khona “ushingamu” lapho kumbiwa, osekuyiminyaka engaba ngu-5700 ubudala. Yikuphi ukwaziswa ngabantu ososayensi ababengakuthola kulokho abakutholile, ubani omunye ushingamu wasendulo ababengamtshela ngaye, futhi lolu cwaningo lwalungayithinta kanjani impi yokulwa nezifo ezihlukahlukene esikhathini esizayo? Izimpendulo zale mibuzo zisilindile embikweni wososayensi. Hamba.
Isisekelo socwaningo
Umlingiswa oyinhloko walolu cwaningo yi-birch resin noma i-birch tar. Lesi sithako esinsundu-mnyama sitholakala ngokubilisa ungqimba olungaphezulu lwegxolo le-birch (igxolo le-birch) esitsheni esivaliwe. Ngaphansi kwezimo ezinjalo, ukushisa kwenzeka ngaphandle kokufinyelela ku-oxygen, i.e. i-distillation eyomile. Ngesikhathi sokushisa, amagxolo e-birch aguqulwa abe yitiyela.
Ezikhathini zasendulo, le nqubo yayisenziwa ezitsheni zobumba phezu komlilo. Ngalezo zinsuku, itiyela lalivame ukusetshenziselwa ukucubungula imikhiqizo yamatshe njengeglue yendawo yonke. Ukutholwa kokuqala kwemivubukulo yetiyela esetshenziswa abantu kubuyela enkathini yePaleolithic.
Kunengqondo ukuthi itiyela lalisetshenziswa “embonini”, ngomqondo ongokomfanekiso. Nokho, abavubukuli bathole iminonjana yamazinyo ezingxenyeni eziningi ze-birch resin. Kungani okhokho bethu babehlafuna itiyela? Kunemibono eminingana yokuchaza lokhu. Okokuqala, itiyela liyaqina ngokushesha lapho selipholile, ngakho-ke ukulihlafuna kungase kube ngenxa yesifiso sokulifudumeza futhi libe thambile emsebenzini. Kukhona inkolelo-mbono ethi itiyela lalihlafunwa ukuze kuncishiswe ubuhlungu obubangelwa izifo zomlomo womlomo, njengoba itiyela libhekwa njengesibulala-magciwane, nakuba libuthakathaka kakhulu. Futhi, abanye abacwaningi bakholelwa ukuthi lezi kwakuyiziqalo zokuhlanzeka kwamazinyo, futhi itiyela lalisebenza njengesixubho sasendulo. Futhi inkolelo-mbono ehlekisayo, kodwa ngakho-ke ayisho lutho, iyinjabulo. Abantu basendulo babekwazi ukuhlafuna inhlaka kanjalo nje, i.e. ngaphandle kwesizathu esihle.
Ukwenza i-birch resin ngokusebenza.
Kuningi ukuqagela ngesihloko sokuhlafuna i-resin ngabantu basendulo, kodwa akekho oke wenza ucwaningo oluningi olunikeza imiphumela ebonakalayo. Ngakho-ke, ososayensi baseNyuvesi yaseCopenhagen banquma ukuhlaziya ucezu lweresin ehlafunwayo etholakala lapho kumbiwa eningizimu yeDenmark (I-1). Ucwaningo lwesampula lubonise ukuthi aliqukethe i-DNA yomuntu kuphela, kodwa ne-microbial DNA, engatshela okwengeziwe nge-microbiome yomlomo. Kwatholakala ne-DNA ezitshalweni ngokusobala ezadliwa umuntu wasendulo ngaphambi kokuhlafuna inhlaka.
I-DNA ilondolozwe kahle kakhulu, ososayensi bayajabula ngokuthi bakwazile ukuhlukanisa i-genome yomuntu ephelele. Leli qiniso elibonakala lingabalulekile empeleni liyintuthuko emivubukulweni nezakhi zofuzo. Iqiniso liwukuthi i-genome ephelele yomuntu wasendulo ngaphambili yayingatholakala kuphela ezinsalela zakhe (ngokuvamile amathambo).
Imiphumela yocwaningo
Ngemva kokuthola “ubufakazi obuphathekayo,” abavubukuli baqala ukubuhlaziya kancane kancane ukuze bathole ukwaziswa okuphelele “ngokusolwa” kwethu, owayehlafuna inhlaka ye-birch.
Isithombe #1
I-Radiocarbon dating, eyenziwa ngokushintsha inani le-isotope ye-radioactive 14C kusampula ehlobene ne-isotopes ye-carbon ezinzile, ithole ukuthi inhlaka iphakathi kweminyaka engu-5858 kanye ne-5661 ubudala (1b). Lokhu kusikisela ukuthi isampula lihlehlela emuva enkathini yokuqala ye-Neolithic. Lesi sikhathi sibizwa nangokuthi "i-New Stone Age", njengoba imikhiqizo yamatshe yaba yinkimbinkimbi, futhi kwavela ubuchwepheshe bokugaya nokugaya izimbobo.
Ukuhlaziywa kwamakhemikhali kusetshenziswa i-Fourier transform infrared spectroscopy (FTIR) kukhiqize i-spectrum efana kakhulu ne-birch tar yesimanje. I-GC/MS (i-gas chromatography/mass spectrometry) yembula ukuba khona kwe-triterpenes betulin ne-lupeol, evame kakhulu kumasampula athathwe ku-birch (1c). Ukuqinisekisa okwengeziwe kokuthi isampula bekuyi-birch kwakuyinsalela yama-dicarboxylic acid namafutha agcwele ahlonzwe yi-GC/MS efanayo.
Ngakho-ke, ososayensi bathole ukuthi isampula yi-birch resin eneminyaka engu-5858 kuya ku-5661 (i-Neolithic yokuqala).
Isinyathelo esilandelayo kwakuwukulandelana kwe-DNA, okwakhiqiza ukulandelana kwe-DNA ebhanqiwe eyisisekelo elinganiselwa ezigidini ezingu-360, cishe ingxenye yesithathu yakhona eyayingase ifaniswe ngokuhlukile ne-human reference genome (hg19).
Ukulandelana kwe-base-pair ye-DNA yomuntu kubonise zonke izici ezitholakala ku-DNA yabantu basendulo: ubude obufushane obumaphakathi bezingcezu, ukuba khona njalo. ama-purines* ukuqhekeka kwe-suture kanye nokwanda kwemvamisa yokushintshwa okubonakalayo i-cytosine* (C) qhubeka i-thymine* (T) emaphethelweni angu-5′ wezingcezu ze-DNA.
I-Purine* (C5N4H4) ingummeleli olula we-imidazo[4,5-d]pyrimidines.
I-Cytosine* (C4H5N3O) isakhi se-organic, isisekelo se-nitrogenous, i-pyrimidine derivative.
I-Timin* (C5H6N2O2) iphuma ku-pyrimidine, enye yezisekelo ezinhlanu ze-nitrogen.
Iphinde yakhiqiza cishe u-7.3 GB wedatha emayelana nokulandelana okungekona okomuntu.
Isampula iqukethe cishe u-30% we-DNA yomuntu engapheli. Lokhu kuqhathaniswa namazinyo namathambo agcinwe kahle abantu basendulo.
Ngokusekelwe ebudlelwaneni obuphakathi kokulandelana kwezisekelo ezibhanqiwe ezihambisana nama-chromosome angu-X kanye no-Y, ososayensi bakwazi ukunquma ubulili besithandwa sasendulo se-gum - owesifazane.
Ukuze ubikezele umbala wezinwele, amehlo kanye nesikhumba, ama-genotypes atholakala amashumi amane nanye I-SNP*ezifakwe ohlelweni .
I-SNP* (i-nucleotide polymorphism eyodwa) - umehluko wokulandelana kwe-DNA ye-nucleotide eyodwa ngosayizi ku-genome yabameleli bohlobo olufanayo noma phakathi kwezifunda ezine-homologous zama-chromosome angama-homologous.
Lokhu kuhlaziywa kwabonisa ukuthi owesifazane wayenesikhumba esinsundu enezinwele ezinsundu ngokumnyama namehlo aluhlaza.
Isithombe #2
Ososayensi bathole ama-SNP angu-593102 ku-genome ngaphansi kocwaningo ayekade efakwe ku-genotype kudathabheyisi>yabantu besimanje abayi-1000 kanye > nama-genomes asendulo ayi-100 ashicilelwe ngaphambilini.
Esithombeni I-2 imiphumela yokuhlaziywa kwengxenye eyinhloko iyaboniswa. Le ndlela yokunciphisa ubukhulu bedatha yasivumela ukuba sinqume ukuthi owesifazane wasendulo ocwaningwa i-genome yakhe kungenzeka ukuthi ungumzingeli waseNtshonalanga (W.H.G.). Ukuqhathanisa allele* abantu besimanje kanye nowesifazane wasendulo waqinisekisa ubulungu bakhe eqenjini elimisiwe (2b).
Alleles* - izinhlobo ezahlukene zofuzo olufanayo, ezitholakala ezindaweni ezifanayo zama-chromosomes angama-homologous. Ama-alleles anquma isiqondiso sokuthuthukiswa kwesici esithile.
Le miphumela ibuye iqinisekiswe ukuhlaziya kwe-qpAdm. Lokhu kuhlaziya kubonisa ukuthi imodeli elula yomugqa, ethatha imvelaphi ye-WHG engu-100% yowesifazane wasendulo, ayikwazi ukulahlwa ngenxa yemodeli eyinkimbinkimbi (2s).
Ukuze kuvezwe kabanzi ukwakheka kwe-taxonomic yokulandelana okungekona okomuntu kusampula, kusetshenziswe i-MetaPhlan2, ithuluzi elakhelwe ngokukhethekile ukwenza iphrofayela ye-taxonomic yokulandelana okufushane okutholiwe. indlela yesibhamu*.
Indlela yesibhamu* - indlela yokulandelanisa izingxenye ezinde ze-DNA, lapho uthola isampula enkulu engahleliwe yezingcezu ze-DNA ehlanganisiwe ikuvumela ukuthi ubuyisele ukulandelana kwe-DNA yasekuqaleni.
Isithombe #3
Ku-"origami" I-3 ibonisa imiphumela yokuhlaziywa kwengxenye eyinhloko eqhathanisa ukwakheka kwe-microbial yesampula yocwaningo kanye namaphrofayili e-microbiome angu-689 avela ku-Human Microbiome Project (HMP). Kube nokuhlanganisana phakathi kwedatha yesampula nedatha ye-HMP, okusho ukuthi zazifana kakhulu. Lokhu kubonakala futhi 3b, okubonisa ukwakheka kwe-microbial ye-resin uma kuqhathaniswa nokufana kwamasampuli amabili enhlabathi (iqoqo lenziwe endaweni efanayo) futhi uma kuqhathaniswa nokwakheka kwamagciwane abantu banamuhla.
Ukuhlaziywa okuningiliziwe kokwakheka kwe-microbial kubonise ukuba khona kwamagciwane I-Neisseria subflava и I-Rothia mucilaginosaFuthi Porphyromonas gingivalis, I-Tannerella forsythia и I-Treponema denticola. Ngaphezu kwalokho, kwatholakala iminonjana yegciwane le-Epstein-Barr.
Izinhlobo eziningana ze-streptococci eziyingxenye yeqembu I-MitisKubandakanya I-Streptococcus viridans и Streptococcus pneumoniae.
Ithebula 1: Uhlu lwayo yonke intela okungeyona eyomuntu etholakala kusampula yetiyela ye-birch.
I-genome yokuvumelana yakhiwe kabusha kusukela ekulandeleni okumataniswe okuyisisekelo S. inyumoniya kanye nokulinganisa kwenani lezingosi ze-heterozygous. Imiphumela yabonisa ukuba khona kwezinhlobo ezimbalwa (isithombe #4).
Isithombe #4
Ukuhlola i-virulence yezinhlobo S. inyumoniyaekhishwe kunhlaka yasendulo, ososayensi bafanisa ama-contig (iqoqo lamasegimenti e-DNA agqagqene) nesizindalwazi esiphelele sezinto eziyingozi, okubavumela ukuthi bakhombe izakhi zofuzo ezaziwayo. ubungozi* S. inyumoniya.
I-Virulence* - izinga lekhono lohlobo lokuthelela umzimba ofundwayo.
Izici ezingamashumi amabili nesithupha ze-virulence ze-S. pneumoniae zikhonjwe kusampula yasendulo, okuhlanganisa i-capsular polysaccharides (CPS), i-streptococcal enolase (Eno), kanye ne-pneumococcal surface antigen A (PsaA).
Ukuhlaziywa kwesampula ye-resin yasendulo kuphinde kwembula ukuba khona kwemikhondo yezinhlobo ezimbili zezitshalo: i-birch (Betula pendula) ne-hazelnut (i-Corylus avellana). Ngaphezu kwalokho, kwatholakala ukulandelana okungaba ngu-50000 XNUMX okwakuhlobene ne-mallard (Anas platyrhynchos, uhlobo lwedada).
Ukuze uthole ulwazi oluningiliziwe ngama-nuances ocwaningo, ngincoma ukubheka и kuyena.
Epilogue
Lolu cwaningo lungabizwa ngokufanelekile ngokuthi luyingqayizivele, uma kubhekwa inani lolwazi olutholiwe. Ngaphambili, i-genome ephelele yomuntu wasendulo yayingabuyiselwa kuphela ezinsalela zakhe (amathambo namazinyo), kodwa kulo msebenzi, ososayensi bakwazi ukuyithola ku-birch resin ehlafunwayo.
Bathole ukuthi ushingamu wasendulo, oneminyaka engu-5700 XNUMX ubudala, wawuhlafunwa owesifazane onesikhumba esimnyama, izinwele ezimnyama namehlo aluhlaza. Le ncazelo yokubukeka iphinde iqinisekise ukuthi umbala wesikhumba okhanyayo phakathi kwezakhamuzi zasengxenyeni esentshonalanga ye-Eurasia waqala ukuvela kamuva. Ukwengeza, izici ezinjalo zangaphandle ziqhathaniswa nalabo abamele abazingeli baseNtshonalanga, okungenzeka ukuthi bahlanganisa owesifazane ogama lakhe lofuzo elitholwe kusampula.
Inzuzo yokutadisha i-resin ehlafunwayo ukuthi inikeza ulwazi mayelana nokwakheka kwe-microbial emgodini womlomo womuntu wasendulo. Lokhu kuhlaziywa kwabonisa ukuba khona kwezinhlobo eziningana zamabhaktheriya (I-Neisseria subflava, I-Rothia mucilaginosa, Porphyromonas gingivalis, I-Tannerella forsythia и I-Treponema denticola). Ngaphezu kwalokho, kwatholakala iminonjana yegciwane le-Epstein-Barr, okungamangazi, uma kubhekwa ukusabalala okukhulu kwaleli gciwane phakathi kwabantu banamuhla (90-95% yabantu abadala bangabathwali balo).
Izinhlobo eziningana ze-streptococci ezivela eqenjini nazo zatholakala I-MitisKubandakanya I-Streptococcus viridans и Streptococcus pneumoniae.
Ngokuqondene nezintandokazi ze-gastronomic zowesifazane wasendulo, ukuhlolwa kokulandelana kwe-DNA okungeyena umuntu, okwakungahlobene namagciwane noma amagciwane, kwathola iminonjana ye-birch, ama-hazelnuts namadada e-mallard. Kungacatshangwa ukuthi lezi zitshalo nezilwane zaziyisisekelo sokudla kwabantu basendulo bangaleso sikhathi. Nokho, maningi amathuba okuthi i-DNA yalezi zitshalo nezilwane ingene kunhlaka ngoba owesifazane wasendulo wayidla ngaphambi nje kokuhlafuna inhlaka. Ngamanye amazwi, lokhu kungase kube isenzakalo esiyingqayizivele.
Kungani inhlaka iwumthombo omuhle kakhulu we-DNA yomuntu wasendulo? Into ewukuthi phakathi nenqubo yokuhlafuna, i-DNA "ivalwe" nge-resin futhi igcinwe kuyo ngenxa yezakhiwo zayo ze-aseptic ne-hydrophobic.
Esikhathini esizayo, ososayensi bahlela ukuhlaziya amanye amasampula atholakele, azosiza ekuqondeni ngokuqhubekayo impilo yabantu basendulo. Ngaphezu kwalokho, ukwakheka kwama-microbial amasampula asendulo kunikeza ukuqonda ngokuvela kwamagciwane omlomo kanye namanye amagciwane.
Kungakhathaliseki ukuthi, ukukhothoza ukwaziswa okuningi ngomuntu ocezwini lwenhlaka ehlafunwayo eyawukhafulela eminyakeni engu-5700 XNUMX edlule kuyimpumelelo emangalisayo. Kwabanye, ulwazi lwesikhathi esidlule, ikakhulukazi olukude kangaka, alubalulekile. Nokho, eqinisweni, lapho sazi okwengeziwe ngokhokho bethu, yilapho siqonda ngokwengeziwe ubuwena bangempela.
NgoLwesihlanu ekuseni:
Ividiyo mayelana nokuthi i-chewing gum ikhiqizwa kanjani emhlabeni wanamuhla.
I-Off-top 2.0:
I-nostalgia encane :)
Siyabonga ngokufunda, hlalani nelukuluku futhi nibe nempelasonto enhle bafana! 🙂
Ezinye izikhangiso 🙂
Siyabonga ngokuhlala nathi. Uyazithanda izindatshana zethu? Ufuna ukubona okuqukethwe okuthakaselayo okwengeziwe? Sisekele ngokufaka i-oda noma ngokuncoma kubangani, , i-analogue ehlukile yamaseva ezinga lokungena, esungulwe yithi ngenxa yakho: (itholakala nge-RAID1 kanye ne-RAID10, kufika kuma-cores angu-24 kuze kufike ku-40GB DDR4).
I-Dell R730xd 2x ishibhile esikhungweni sedatha se-Equinix Tier IV e-Amsterdam? Lapha kuphela eNetherlands! I-Dell R420 - 2x E5-2430 2.2Ghz 6C 128GB DDR3 2x960GB SSD 1Gbps 100TB - isuka ku-$99! Funda mayelana
Source: www.habr.com