Zeitschriftenartikel: „Plochy“

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Roegel, Denis. „Kulové plochy, hlavní kružnice a rovnoběžky“. Zpravodaj Československého sdružení uživatelů TeXu 20, Nr. 1-2 (2010): 23–38. http://dx.doi.org/10.5300/2010-1-2/23.

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FELGENTRAEGER, W. „Calculation of heat transfer area of conical bottom fermenting vessels.“ Kvasny Prumysl 38, Nr. 1 (01.01.1992): 17–20. http://dx.doi.org/10.18832/kp1992006.

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3

Rumanová, Lucia, und Vjera Kiš. „Interesting Ruled Surfaces in Technical Practice and Real-life“. Acta Mathematica Nitriensia 2, Nr. 1 (2016): 19–26. http://dx.doi.org/10.17846/amn.2016.2.1.19-26.

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Bulková, Kristína, und Soňa Čeretková. „Interesting Ruled Surfaces in Technical Practice and Real-life“. Acta Mathematica Nitriensia 2, Nr. 2 (Oktober 2016): 28–34. http://dx.doi.org/10.17846/amn.2016.2.2.28-34.

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5

Vágová, Renáta. „Interesting Ruled Surfaces in Technical Practice and Real-life“. Acta Mathematica Nitriensia 3, Nr. 2 (Oktober 2017): 24–31. http://dx.doi.org/10.17846/amn.2017.3.2.24-31.

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6

Poláková, Zuzana, Václav Furmánek und Iveta Kaczarová. „Hrob dieťaťa v nádobe z plochy zaniknutého kostola a cintorína v Pincinej (okr. Lučenec)“. Archaeologia historica, Nr. 2 (2016): 285–307. http://dx.doi.org/10.5817/ah2016-2-14.

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7

Mihálik, Jakub. „Russelliánský monismus jako svébytné metafyzické stanovisko“. FILOSOFIE DNES 9, Nr. 2 (30.08.2018): 23–43. http://dx.doi.org/10.26806/fd.v9i2.259.

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Příspěvek kriticky reaguje na pojednání o russelliánském monismu v monografii Jaké to je, nebo o čem to je? Tomáše Hříbka. Podle Hříbka russelliánský monismus, přístup k fenomenálnímu vědomí inspirovaný vhledy Bertranda Russella, nepředstavuje skutečnou alternativu vůči materialismu, dualismu a idealismu. Autor příspěvku argumentuje, že russelliánský monismus naopak lze pokládat za svébytné metafyzické stanovisko, jež se navíc vyhýbá hlavním úskalím těchto tradičních přístupů. Nejprve odpovídá na námitku, že fundamentální jsoucna neutrálního monismu jsou ve skutečnosti mentalistická, a tedy nikoli neutrální.V souvislosti s neutrálním monismem rovněž poukazuje na problémy Hříbkovy definice fyzikalismu v duchu via negativa. Autor dále vysvětluje, proč na rozdíl od dualismu nepředstavuje pro russelliánský monismus vážnou obtíž kauzální uzávěra fyzična, a upozorňuje, že russelliánský monismus dokáže lépe než materialismus odpovědět na výzvy, jako jsou argument z myslitelnosti a argument z poznání. Ačkoli tedy russelliánský monismus má s materialismem, dualismem a idealismem jistě styčné plochy, daří se mu vyhnout nejvážnějším obtížím těchto směrů, a máme proto dobrý důvod chápat jej jako svébytný a slibný přístup k fenomenálnímu vědomí.

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Ugarković, Damir, Ana Hodak, Ivica Tikvić und Krešimir Popić. „Vitalnost šumskoga drveća na bioindikacijskoj plohi u Nacionalnom parku Plitvička jezera“. Nova mehanizacija šumarstva 41 (10.12.2020): 1–7. http://dx.doi.org/10.5552/nms.2020.1.

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Osutost krošanja stabala jedan je od indikatora vitalnosti šumskoga drveća. Cilj je istraživanja bio analizirati osutost krošanja stabala obične jele i obične smreka s bioindikacijske plohe u Nacionalnom parku Plitvička jezera. Iz Upisnika Razine 1 Nacionalnoga programa motrenja oštećenosti šumskih ekosustava prikupljeni su podaci o osutosti krošanja stabala obične jele i obične smreke s bioindikacijske plohe u Nacionalnom parku Plitvička jezera. Vrijednosti samokalibriranoga Palmerova indeksa oštrine suhoće (scPDSI) prikupljene su s mrežne aplikacije KNMI Climate Explorer. S obzirom na osutost krošanja i mortalitet stabala obična jela i obična smreka dobre su vitalnosti na bioindikacijskoj plohi. Suša je utjecala na značajnu osutost krošanja stabala obične smreke, dok kod obične jele to nije bio slučaj. Potrebno je nastaviti promatranje vitalnosti šumskoga drveća te povećati broj ploha s motrenjem osutosti krošanja stabala, klime i ostalih ekoloških čimbenika u Nacionalnom parku.

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Benko, Miroslav. „Sustavna praćenja konverzije sadnicama hrasta lužnjaka (Quercus robur L.) i kitnjaka (Quercus petraea L.) s obzirom na različit način sadnje“. Šumarski list 144, Nr. 9-10 (27.10.2020): 485–95. http://dx.doi.org/10.31298/sl.144.9-10.5.

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Istraživanja su obavljena u nizinskom dijelu Varaždinske županije, u šumi posebne namjene „FOPER“, g. j. „Zelendvor odsjek 13c na oko 3 km udaljenosti od rijeke Drave na nadmorskoj visini od 190 m, u području gdje su sađene pretežito kulture smreke, borovca i bagrema iako je stanište pogodno za sadnju i uzgoj hrasta. S obzirom na promijenjene ekološke i klimatološke prilike osnovana je 2012. godine trajna pokusna ploha veličine 2,00 ha. Na plohi su posađene trogodišnje (2 + 1) sadnice hrasta lužnjaka (Quercus robur L.) i hrasta kitnjaka (Quercus petraea L.) i to na dva načina. Jedan dio u razmaku sadnje 3 x 3 m u polipropilenskim štitnicima. Drugi dio razmaka sadnje 2 x 2 m uobičajenim načinom (bez štitnika). Cijela je površina podijeljena na 24 pod plohe približnih površina. Na jednoj plohi nalazi se jedna vrsta drveća. Raspored vrsta je naizmjeničan od plohe do plohe. Upotrijebljen je randomizirani oblik metode, sa 4 bloka i 3 ponavljanja. Visine biljaka mjerene su 5 godina uzastopce za vrijeme mirovanja vegetacije. Prsni promjeri mjereni su na kraju promatranog razdoblja kada su biljke bile više od 1,30 m. Učešće i intenzitet pepelnice utvrđivan je tri godine tijekom ljetnih mjeseci. Cilj istraživanja je proučavanje rasta i razvoja sadnica hrasta lužnjaka i hrasta kitnjaka na prostoru gdje do sada nije bilo uobičajeno saditi navedene vrste, iako za to postoje ekološko gospodarski uvjeti. Istraživanja ukazuju kako je broj biljaka nakon 5 godina izmjere smanjen je za 14%. Kod hrasta lužnjaka smanjen je za 4 do 8%, a kod hrasta kitnjaka za 17 do 22%. Visine i prsni promjeri stabala u štitnicima značajno su veći bez obzira na vrstu drveća. Visine i prsni promjeri hrasta lužnjaka značajno su veće od hrasta kitnjaka. Nije utvrđena povezanost između visina stabala i prisutnosti pepelnice.

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Zeman, Tomáš, und Miroslav Králík. „Historický přehled principů tvorby metod pro odhad výšky postavy člověka na základě skeletu“. Anthropologia integra 3, Nr. 1 (01.01.2012): 7–22. http://dx.doi.org/10.5817/ai2012-1-7.

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Z historického přehledu principů tvorby metod pro odhad výšky postavy člověka na základě skeletu vyplývá, že lze vymezit čtyři základní skupiny metod: metody podílové, regresní, anatomické a metody organické korelace. Každá má svá specifika a úskalí, která bezprostředně vyplývají z jejich matematické konstrukce. Nejčastěji se k odhadu výšky postavy používají některé rozměry dlouhých kostí končetin. Bylo teoreticky prokázáno, že nejpřesnější možné odhady poskytují metody regresní, zejména když k odhadu využijeme kombinaci rozměrů z více kostí. Nutným předpokladem použití lineární regrese je však užití pouze těch rovnic, které byly vytvořeny na základě výběru z populace, z níž pochází i odhadovaný jedinec. V opačném případě, tj. pokud je lineární regrese použita pro odhad jedinců z populace jiné, může dojít k menšímu či většímu vychýlení odhadu. Tato skutečnost byla již mnohokrát empiricky ověřena. Teoretický rozbor lineární regrese ukázal, že jde o důsledek jevu označovaného jako „regrese k průměru“. Metody organické korelace (založené na minimalizaci součtu plochy reziduálních trojúhelníků) jsou méně náchylné k systematické chybě, jsou však také méně přesné. Lze je ale aplikovat na libovolnou populaci a pro jednotlivé případy z neznámé populace jsou nejpřesnější. Anatomické metody jsou aplikovatelné jen v případě dostatečně zachovaného skeletu. Jsou založeny na součtu výšek všech (nebo téměř všech) kostí skeletu, které se na výšce postavy přímo podílejí. Rozdíl mezi výškou postavy za života a součtem délek kostí skeletu od lebky po patní kost se pohybuje v řádu centimetrů a prostor pro chybu odhadu je tak malý. Ať už pak k odhadu výšky ze skeletu v rámci anatomické metody použijeme kterýkoliv ze tří výše uvedených matematických postupů (podílová metoda, lineární regrese, organická korelace), rozdíly mezi jimi pořízenými odhady jsou zanedbatelné a jejich rozlišování pozbývá smyslu. Celkově jsou tedy anatomické metody nejpřesnější a je třeba je doporučit, kdykoliv to stav zachování skeletu dovolí.

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Španjol, Željko, Milan Vojinović, Ivan Tolić, Ivana Gašparović, Nikola Vrh und Boris Dorbić. „Vegetative and dendrological characteristics of Hober forest park in Korčula“. Šumarski list 144, Nr. 7-8 (31.08.2020): 409–21. http://dx.doi.org/10.31298/sl.144.7-8.6.

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Sustavnih istraživanja biološko-ekoloških obilježja cjelokupnog područja i same park-šume Hober nije bilo do sada. Strukturna obilježja sastojine nalazimo tek u Planu gospodarenja za park-šumu Hober (2006-2015). Šumarsku problematiku nalazimo u radu Vojinovića (1997). Dendrološka istraživanja imamo u radovima Denich i Draganović (1985), Vojinović (1997),Fabris (2001), Onofri (2002). Izostala je njegova cjelovita inventarizacija. Današnje stanje park-šume Hober karakterizira njegova zapuštenost i neuređenost kako šumske vegetacije i dendrološko-hortikulturnih, tako i vrtno-arhitektonskih sadržaja. Prisutna je koncepcijska nedefiniranost cjelokupnog područja Hobera. Park-šuma Hober u vegetacijskom smislu pripada šumskoj zajednici šuma alepskog bora i hrasta crnike (Querco ilicis – Pinetum halepensis Loisel 1971). Upravo iz razloga vegetacijske i strukturne neujednačenosti, postavljeno je 7 pokusnih ploha u samoj park-šumi, te još 4 izvan nje. Cilj je detaljnom vegetacijskom i strukturnom analizom izdvojiti pojedina područja, dati njihov opis i prikazati njihovo stanje, što se kasnije može upotrijebiti u svrhu zoniranja prostora. Analizirana istraživanja pokazuju da u sloju drveća alepski bor prevladava na plohama 1,2,3 i 9; crnika na plohama 4 i 5 te obični čempres na plohama 6 i 7. U sloju grmlja najzastupljenija je lemprika koja dolazi na svim plohama. Zatim su tu širokolisna zelenika i tršlja. Iz tablice 2 vidimo da je na svim plohama pokrovnost vegetacijom potpuna osim na plohi 6, gdje je rijetka makija. Sloj drveća je prevladavajući osim na plohama 8, 10 i 11, gdje je prisutna makija. Zamjetno je da je kod razvijenih sastojina podjednako gust sloj drveća i grmlja. Tu odstupaju plohe 6 i dijelom ploha 9 te plohe 10 gdje je makija te ploha 11 koja je prirodna sukcesija šumske vegetacije na zapuštenim poljoprivrednim površinama. Osim kod makije imamo vrlo visok drvni volumen (drvna zaliha) koji se ovisno o razvoju sastojine kreće od 100 do čak 270 m<sup>3</sup>/ha. Broj stabala je isto vrlo velik i kreće se od 1000 do 2700 po ha. Svi ti podaci ukazuju na neuređenost i izostanak bilo kakvih uzgojnih radova. Cilj ovog rada je istražiti vegetacijska, dendrološka, šumsko-uzgojna i strukturna obilježja cjelokupnog područja Hober. Ona su primarni pokazatelj stanje i dat će smjernice za njegovu buduću biološku i prostornu valorizaciju.

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Vachala, Břetislav. „Ahmosova „Zelená“ svatyně (Staroegyptské spolium ve středověké Káhiře)“. Anthropologia integra 11, Nr. 1 (29.06.2020): 51–57. http://dx.doi.org/10.5817/ai2020-1-51.

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Mezi významné stavby středověké islámské Káhiry, kde se objevují staroegyptská spolia, patří mešita a chanqa s hrobkou Sajf ad-Dína Šajchú al-‛Umarího, nejvlivnějšího emíra za vlády sultána an-Násira Hasana (1347–1351, 1354–1361). Zvlášť významné je spolium umístěné nad vchodem do Šajchúovy chanqy. Jedná se o opracovaný monolitický kamenný blok (286 x 77 x 57 cm), který zde byl sekundárně použit jako dveřní překlad (obr. 1–3). Jeho materiálem je siltovec z lomů ve Wádí Hammámátu. Původ bloku prozrazují písemná svědectví středověkých arabských učenců, historiků a geografů, především ‛Abd al-Latífa (1162–1231), al-Qalqašandího (1355–1418) a al-Maqrízího (1364–1442). Je jím obdivovaná Zelená svatyně v Menneferu, která se při převozu do Káhiry rozlomila a její kvalitní zelený kámen byl znovu použit při stavbě mešity a chanqy emíra Šajchú. Došlo k tomu někdy těsně po roce 1350, přičemž stavba Šajchúovy chanqy byla dokončena v roce 1355. Dotyčný blok pochází z čelního horního zakončení svatyně (řecky naos), což prokazuje na něm vyznačená konkávní římsa v kombinaci se zaoblenou římsou (oblounkem) (obr. 4). Do rovné plochy pod zaoblenou římsou je v hlubokém reliéfu pečlivě vytesán po celé délce bloku (286 cm) hieroglyfický nápis (obr. 5) zaznamenaný v jednom vodorovném řádku zprava doleva (výška 10 cm), který obsahuje titulaturu Ahmose II., což umožňuje datování Zelené svatyně do doby jeho vlády (569–526 př. n. l.). V textu bylo úmyslně zahlazeno panovníkovo jméno (Chenemibre Ahmose Saneit), což má na svědomí perský král Kambýsés, který v roce 525 př. n. l. obsadil Egypt. Přibližně po 1900 letech byl blok z Ahmosovy svatyně znovu použit jako dveřní překlad nad vchodem do Šajchúovy chanqy. Vedle ryze praktického důvodu využít dostupný, již opracovaný blok z kvalitního kamene tu byl i druhý, který vycházel z tradiční lidové víry v magickou moc prastarých, jak zdobených, tak zvláště zdobených a popsaných kamenů. Taková spolia použitá jako dveřní překlady a prahy na viditelných místech při vstupech do středověkých (a raně novověkých) islámských sakrálních i profánních staveb v Káhiře měla apotropaickou a ochrannou moc. Jejich účelem bylo odvrátit od budov působení zlých sil v podobě bouří, lijáků, zemětřesení, nilské záplavy či epidemií a zamezit proniknutí myším, krysám, hadům, štírům, mouchám, komárům i ptákům. Tím také měla být samozřejmě zajištěna ochrana jejich četných návštěvníků a obyvatel.

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Teyssler, Petr, und Vojtěch Havlas. „Paediatric flat foot“. Pediatrie pro praxi 18, Nr. 1 (04.04.2017): 18–21. http://dx.doi.org/10.36290/ped.2017.004.

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Halperin, Charles. „“National Identity in Premodern Rus”“. Russian History 37, Nr. 3 (2010): 275–94. http://dx.doi.org/10.1163/187633110x510446.

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AbstractThis article is a commentary on some of the conclusions of Serhii Plokhy's The Origin of the Slavic Nations. Premodern Identities in Russia, Ukraine and Belarus. Plokhy addressed ethnocultural (national) identities and national identity projects from the tenth to the early eighteenth century. This essay is concerned with Kievan Rus', the Mongol impact on the East Slavs, and Muscovite history from the fourteenth to the sixteenth century. It offers alternative interpretations both of the historical background which Plokhy outlines for the evolution of East Slavic peoples and of Plokhy's interpretations of various historical, political, religious and literary texts. The chronology of the translatio of the myth of the Rus' Land from Kievan Rus' to Moscow is still a matter of contention. In synthesizing the views of such historians as Edward Keenan and Donald Ostrowski, Plokhy has attributed too much influence to the Mongols on Russian institutional and cultural history. Plokhy has failed to be consistent in his application of Keenan's criticism of sources and Keenan's concept of sixteenth-century Muscovite society and culture. Finally, Plokhy somewhat oversimplifies the cultural heterogeneity of Ivan the Terrible and Ivan the Terrible's Muscovy. These criticisms are a tribute to Plokhy's challenging but inspiring monograph.

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Feldmann, Gérard. „Liver ploidy“. Journal of Hepatology 16, Nr. 1-2 (Januar 1992): 7–10. http://dx.doi.org/10.1016/s0168-8278(05)80087-x.

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Fehervari, Zoltan. „Ploidy spotting“. Nature Immunology 13, Nr. 12 (16.11.2012): 1143. http://dx.doi.org/10.1038/ni.2482.

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Kachova, Vania, und Angel Ferezliev. „Improved characteristics of Populus sp. ecosystems by agroforestry practices“. Šumarski list 144, Nr. 1-2 (28.02.2020): 51. http://dx.doi.org/10.31298/sl.144.1-2.5.

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Agrošumarstvo je višenamjenski, okolišno povoljan i moderan sustav korištenja zemljišta kojim se mogu postići ekonomske, okolišne i socijalne dobrobiti za društvo. Ovom studijom se to potvrđuje na primjeru plantaža topola uz rijeku Dunav u regiji Vidin (Bugarska) u koje je uveden i uzgoj povrtlarskih kultura. Primjenom agrošumarskih metoda proizvodnost plantaža topola je povećana. Prosječni prsni promjeri i prosječne visine stabala u područjima u kojima je primijenjeno agrošumarstvo su veći u odnosu na plantaže bez primjene agrošumarstva iste dobi. Desetgodišnja plantaža uz primjenu agrošumarstva ima prosječni prsni promjer stabala od 8,70 cm i prosječnu visinu od 7,44 m, dok kontrolna ploha ima lošije dendrometrijske značajke (prsni promjer od 7,44 cm i prosječnu visinu od 7,04 cm). Uspostava agrošumarskog sustava također je dovela i do poboljšanja značajki tla. Sadržaj humusa u tlu je veći u plantažama s primijenjenim agrošumarskim sustavom (4,3-2,5%) u odnosu na kontrolnu plohu (2%). S obzirom na sastav organske tvari, kontrolna ploha ima najmanji udio huminskih kiselina (stabilni dio organske tvari) (0,20%) u usporedbi s agrošumarskim sustavom (0,78-0,49%). Ujedno, kontrolna površina ima najveći udio fulvo kiselina (mobilni dio organske tvari (0,62%) u usporedbi s agrošumarskim sustavom (0,46-0,05%) i najveći udio “agresivnih” fulvo kiselina (0,05%). Na temelju rezultata ovoga istraživanja, razložno je preporučiti agrošumarski sustav gospodarenja kao odgovarajući za uzgajanje plantaža topola na fluvisolima regije Vidin.

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Chaves, Mark. „In the Meantime... (Response to Ploch)“. Sociological Analysis 49, Nr. 3 (1988): 304. http://dx.doi.org/10.2307/3711592.

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Avanzi, Mauro P., Amanda Chen, Alexandra Haugh und W. Beau Mitchell. „Optimizing Megakaryocyte Polyploidization in Culture by Targeting Multiple Pathways of Cytokinesis“. Blood 118, Nr. 21 (18.11.2011): 4820. http://dx.doi.org/10.1182/blood.v118.21.4820.4820.

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Abstract Abstract 4820 Introduction: The large-scale laboratory production of platelets for transfusion purposes using cord blood stem cells is one of goals of stem cell research. One step toward this goal will be to produce and expand megakaryocytes with high ploidy which are capable of releasing higher amounts of platelets than low ploidy cells. Megakaryocyte polyploidization requires a combination of distinct cellular mechanisms, including actin polymerization, myosin activation, microtubule formation, and increased DNA production. Normal bone marrow megakaryocytes reach a DNA content of 128N, with a modal ploidy of 16N. In contrast, cultured human megakaryocytes have typically reached a maximum ploidy of 16N with the majority of cells at 2N/4N. In this study we combined the inhibition of each of the principle mechanisms driving cytokinesis with the goal of driving polyploidization of cultured CD34+ umbilical cord blood cells. The effects of inhibiting each cytokinesis process was characterized by its effects on cell expansion and ploidy, and the additive or inhibitory effects of combining inhibition of multiple processes was determined. The results of this study provide a strategy to produce high ploidy megakaryocytes and provide new insight into the mechanisms underlying megakaryocyte polyploidization. Methods: Human cord blood derived megakaryocytes were cultured with thrombopoietin (TPO) and stem cell factor (SCF) along with reagents that inhibit different mechanisms of the cytokinesis process: Rho-Rock inhibitor, Y27632 (RRI); Src-inhibitor, SU6656 (SI); Nicotinamide (NIC); Aurora-B inhibitor, ZM447439 (ABI); and Myosin Light Chain Kinase Inhibitor (MLCKI). Reagents were added in one single day (day 8) or on three consecutive days (days 8–10) and ploidy was analyzed on day 11 of culture with PI/RNase. Combinations of reagents were used in order to determine their additive or inhibitory interactions and to maximize megakaryocyte ploidy. Results: Treatment with RRI resulted in the highest megakaryocyte ploidy. Up to 48% of megakaryocytes were high ploidy (≥ 8N), with highest ploidy ≥ 64N (p = 0.0007 vs. control). Treatment with NIC resulted in up to 24% of cells reaching high ploidy, with a maximum ploidy of ≥ 32N (p = 0.003 vs. control). Treatment with SI resulted in up to 24% megakaryocytes reaching high ploidy, with a maximum ploidy of ≥ 32N (p = 0.026 vs. control). Treatment with ABI resulted in up to 28% of megakaryocytes reaching high ploidy, with a maximum ploidy of ≥ 32N (p = 0.018 vs. control). The MLCKI had no effect in final ploidy. The combinations of reagents all significantly increased both percentage of cells reaching high ploidy and the highest ploidy compared to control. However, none of the combinations achieved a more robust effect in final ploidy than the RRI alone. However, the combination of MLCKI with SI, NIC and ABI increased the high ploidy cells up to 51.3% with a maximum ploidy ≥ 64N (p < 0.0001 vs. control) (Table 1). Conclusion: The RRI proved to be the most effective agent in driving umbilical cord-derived megakaryocyte polyploidization. All other reagents tested, except MLCKI, also moderately increased megakaryocyte ploidy. RRI and MLCKI, both reagents that inhibit the late stages of cytokinesis and furrow formation, resulted in opposite ploidy outcomes, suggesting that RRI acts on ploidy through pathways other than inhibition of myosin activation. While MLCK is active primarily in the late stages of cytokinesis, the Rho/Rock pathway overlaps with other signaling pathways involved in cytokinesis, including src activation in actin polymerization and Aurora kinase activity in microtubule formation. Although inhibition of myosin light chain activation by itself did not appear to drive polyploidization, the combination of MLCKI with other cytokinesis inhibitors increased polyploidization to the same extent as RRI. Our results indicate that induction of high ploidy in cord blood derived megakaryocytes involves a combination of distinct cytokinesis pathways. Disclosures: No relevant conflicts of interest to declare.

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Cramer, Christopher S. „Laboratory Techniques for Determining Ploidy Levels“. HortScience 33, Nr. 3 (Juni 1998): 555c—555. http://dx.doi.org/10.21273/hortsci.33.3.555c.

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The determination of ploidy levels is essential for breeding asexually propagated and polyploid crops that may have ploidy chimeras in their tissues or have several polyploid series. This presentation will discuss a laboratory for teaching students how to determine ploidy levels in different plant tissues using different techniques. The different methods for ploidy determination include root tip squashes, pollen mother cell squashes, pollen grain size and germinal pore counts, stomata size and density determination, and gross morphology. After completing these laboratory experiments, students will be able 1) to initiate a study of ploidy determination, 2) to determine the correct course of action in determining ploidy level, and 3) to recognize the various steps required to determine ploidy level in plants.

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Newnham, Randall E. „Review of Serhii Plokhy. Chernobyl: The History of a Nuclear Catastrophe.“ East/West: Journal of Ukrainian Studies 8, Nr. 1 (28.04.2021): 259–61. http://dx.doi.org/10.21226/ewjus652.

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Linhartová, Z., M. Havelka, M. Pšenička und M. Flajšhans. „Interspecific hybridization of sturgeon species affects differently their gonadal development“. Czech Journal of Animal Science 63, No. 1 (04.12.2017): 1–10. http://dx.doi.org/10.17221/37/2016-cjas.

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Gonad development in fish is generally assumed to be negatively influenced by interspecific hybridization, resulting in sterility or sub-sterility. However, this is not the case in sturgeons (Acipenseridae), in which fertile hybrids are common. In the present study, we investigated gonad development in several sturgeon interspecific hybrids and purebred species. Six interspecific hybrid groups and three purebred groups were analyzed including 20 hybrid specimens with even ploidy, 40 specimens having odd ploidy levels, and 30 purebred specimens. Hybrids of species with the same ploidy (even ploidy – 2n, 4n) exhibited normally developed gonads similar to those seen in purebred specimens. In contrast, hybrids of species differing in ploidy (odd ploidy – 3n) did not display fully developed gonads. Ovaries were composed of oocytes or nests of differentiating oocytes that ceased development in early stages of meiosis (pachytene to zygotene) with a higher content of adipose and apoptotic tissue. Testes contained single spermatogonia along with Sertoli cells and spaces lacking germ cells. The obtained results showed that gonad development was influenced by genetic origin and ploidy of the sturgeon hybrids and were consistent with full fertility of hybrids with even ploidy. Sterility of females, but possibly limited fertility of males, is suggested for hybrids with odd ploidy.

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Hummer, K. E., N. V. Bassil, H. P. Rodríquez Armenta und J. W. Olmstead. „Vacciniumspecies ploidy assessment“. Acta Horticulturae, Nr. 1101 (September 2015): 199–204. http://dx.doi.org/10.17660/actahortic.2015.1101.30.

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Ferguson, A. R., I. E. W. O'Brien und G. J. Yan. „PLOIDY IN ACTINIDIA“. Acta Horticulturae, Nr. 444 (Mai 1997): 67–72. http://dx.doi.org/10.17660/actahortic.1997.444.7.

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Stamey, Thomas A. „DNA ploidy status“. Urology 45, Nr. 4 (April 1995): 563–65. http://dx.doi.org/10.1016/s0090-4295(99)80043-0.

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Fu, Yao S., und Ralph M. Richart. „Ploidy and Condylomata“. American Journal of Surgical Pathology 13, Nr. 2 (Februar 1989): 171. http://dx.doi.org/10.1097/00000478-198902000-00014.

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Griese, Marco, Christian Lange und Jörg Soppa. „Ploidy in cyanobacteria“. FEMS Microbiology Letters 323, Nr. 2 (06.09.2011): 124–31. http://dx.doi.org/10.1111/j.1574-6968.2011.02368.x.

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Holding, Cathy. „Ploidy predicts lifestyle“. Genome Biology 5 (2004): spotlight—20040714–01. http://dx.doi.org/10.1186/gb-spotlight-20040714-01.

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Thoma, Clemens. „Decoding hepatocyte ploidy“. Nature Reviews Gastroenterology & Hepatology 15, Nr. 11 (15.10.2018): 656. http://dx.doi.org/10.1038/s41575-018-0076-8.

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Chopard, Thomas. „Serhii Plokhy, ed., The Future of the Past“. Cahiers du monde russe 59, Nr. 4 (01.10.2018): 721–23. http://dx.doi.org/10.4000/monderusse.10925.

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Corash, L., HY Chen, J. Levin, G. Baker, H. Lu und Y. Mok. „Regulation of thrombopoiesis: effects of the degree of thrombocytopenia on megakaryocyte ploidy and platelet volume“. Blood 70, Nr. 1 (01.07.1987): 177–85. http://dx.doi.org/10.1182/blood.v70.1.177.177.

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Abstract We have established a murine model and techniques with which to serially study thrombocytopoiesis after induction of experimental immune thrombocytopenia of variable severity and duration. Bone marrow megakaryocyte ploidy distribution was determined by using unfractionated bone marrow, a polyclonal megakaryocyte-specific probe, and two-color, fluorescence-activated flow cytometry. With these techniques, the modal megakaryocyte ploidy class in normal murine bone marrow was 16N. Serial studies of bone marrow megakaryocyte ploidy after the induction of acute, severe thrombocytopenia (platelet count, less than 0.05 X 10(6) microL) demonstrated no detectable change in the ploidy distribution at 12, 24, and 36 hours after the onset of thrombocytopenia. At 48 hours, the modal ploidy class shifted from 16N to 32N, and the 64N class increased significantly (P less than .001). The ploidy distribution returned to normal 120 hours after the onset of thrombocytopenia. A lesser degree of thrombocytopenia (platelet count reduction to 0.100 to 0.200 X 10(6)/microL) delayed the modal ploidy class shift from 16N to 32N until 72 hours after the onset of thrombocytopenia. Chronic, severe thrombocytopenia (platelet count, less than 0.05 X 10(6)/microL for seven days) resulted in a modal ploidy class shift from 16N to 32N during the thrombocytopenic phase and an enhanced increase in the 64N megakaryocyte class during the recovery phase. Mean platelet volume (MPV) was simultaneously measured on isolated total platelet populations after induction of thrombocytopenia. MPV was significantly increased (P less than .001) as early as eight hours after the onset of acute, severe thrombocytopenia, 40 hours before a shift in the ploidy distribution. Mild thrombocytopenia (platelet count reduction to 0.400 X 10(6)/microL) was not associated with a ploidy shift but did result in a significantly increased MPV (P less than .001). These studies demonstrate that the temporal relationship and magnitude of the effects of thrombocytopenia upon megakaryocyte ploidy distribution are dependent upon the degree and the duration of the thrombocytopenic stimulus and that the effects of experimental thrombocytopenia on platelet volume and megakaryocyte ploidy are dissociated.

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Corash, L., HY Chen, J. Levin, G. Baker, H. Lu und Y. Mok. „Regulation of thrombopoiesis: effects of the degree of thrombocytopenia on megakaryocyte ploidy and platelet volume“. Blood 70, Nr. 1 (01.07.1987): 177–85. http://dx.doi.org/10.1182/blood.v70.1.177.bloodjournal701177.

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We have established a murine model and techniques with which to serially study thrombocytopoiesis after induction of experimental immune thrombocytopenia of variable severity and duration. Bone marrow megakaryocyte ploidy distribution was determined by using unfractionated bone marrow, a polyclonal megakaryocyte-specific probe, and two-color, fluorescence-activated flow cytometry. With these techniques, the modal megakaryocyte ploidy class in normal murine bone marrow was 16N. Serial studies of bone marrow megakaryocyte ploidy after the induction of acute, severe thrombocytopenia (platelet count, less than 0.05 X 10(6) microL) demonstrated no detectable change in the ploidy distribution at 12, 24, and 36 hours after the onset of thrombocytopenia. At 48 hours, the modal ploidy class shifted from 16N to 32N, and the 64N class increased significantly (P less than .001). The ploidy distribution returned to normal 120 hours after the onset of thrombocytopenia. A lesser degree of thrombocytopenia (platelet count reduction to 0.100 to 0.200 X 10(6)/microL) delayed the modal ploidy class shift from 16N to 32N until 72 hours after the onset of thrombocytopenia. Chronic, severe thrombocytopenia (platelet count, less than 0.05 X 10(6)/microL for seven days) resulted in a modal ploidy class shift from 16N to 32N during the thrombocytopenic phase and an enhanced increase in the 64N megakaryocyte class during the recovery phase. Mean platelet volume (MPV) was simultaneously measured on isolated total platelet populations after induction of thrombocytopenia. MPV was significantly increased (P less than .001) as early as eight hours after the onset of acute, severe thrombocytopenia, 40 hours before a shift in the ploidy distribution. Mild thrombocytopenia (platelet count reduction to 0.400 X 10(6)/microL) was not associated with a ploidy shift but did result in a significantly increased MPV (P less than .001). These studies demonstrate that the temporal relationship and magnitude of the effects of thrombocytopenia upon megakaryocyte ploidy distribution are dependent upon the degree and the duration of the thrombocytopenic stimulus and that the effects of experimental thrombocytopenia on platelet volume and megakaryocyte ploidy are dissociated.

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King, K. C., O. Seppälä und M. Neiman. „Is more better? Polyploidy and parasite resistance“. Biology Letters 8, Nr. 4 (18.01.2012): 598–600. http://dx.doi.org/10.1098/rsbl.2011.1152.

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Ploidy-level variation is common and can drastically affect organismal fitness. We focus on the potential consequences of this variation for parasite resistance. First, we elucidate connections between ploidy variation and key factors determining resistance, including allelic diversity, gene expression and physiological condition. We then argue that systems featuring both natural and artificially manipulated ploidy variation should be used to evaluate whether ploidy level influences host–parasite interactions.

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Jeleček, Leoš, und Jan Kabrda. „Land Use Changes in Czechia in 1990--2010 and Their Societal Driving Forces“. Geografické informácie 19, Nr. 2 (2015): 38–61. http://dx.doi.org/10.17846/gi.2015.19.2.38-61.

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Krause, Martin, František Dolák und Marie Froňková. „The knowledge of nurses on the disinfection of reusable objects and surfaces in clinical practice“. Kontakt 23, Nr. 1 (03.03.2021): 8–13. http://dx.doi.org/10.32725/kont.2021.008.

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Bou-Nader, Myriam, Stefano Caruso, Romain Donne, Séverine Celton-Morizur, Julien Calderaro, Géraldine Gentric, Mathilde Cadoux et al. „Polyploidy spectrum: a new marker in HCC classification“. Gut 69, Nr. 2 (12.04.2019): 355–64. http://dx.doi.org/10.1136/gutjnl-2018-318021.

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ObjectivesPolyploidy is a fascinating characteristic of liver parenchyma. Hepatocyte polyploidy depends on the DNA content of each nucleus (nuclear ploidy) and the number of nuclei per cell (cellular ploidy). Which role can be assigned to polyploidy during human hepatocellular carcinoma (HCC) development is still an open question. Here, we investigated whether a specific ploidy spectrum is associated with clinical and molecular features of HCC.DesignPloidy spectra were determined on surgically resected tissues from patients with HCC as well as healthy control tissues. To define ploidy profiles, a quantitative and qualitative in situ imaging approach was used on paraffin tissue liver sections.ResultsWe first demonstrated that polyploid hepatocytes are the major components of human liver parenchyma, polyploidy being mainly cellular (binuclear hepatocytes). Across liver lobules, polyploid hepatocytes do not exhibit a specific zonation pattern. During liver tumorigenesis, cellular ploidy is drastically reduced; binuclear polyploid hepatocytes are barely present in HCC tumours. Remarkably, nuclear ploidy is specifically amplified in HCC tumours. In fact, nuclear ploidy is amplified in HCCs harbouring a low degree of differentiation and TP53 mutations. Finally, our results demonstrated that highly polyploid tumours are associated with a poor prognosis.ConclusionsOur results underline the importance of quantification of cellular and nuclear ploidy spectra during HCC tumorigenesis.

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Kuter, DJ, und RD Rosenberg. „Regulation of megakaryocyte ploidy in vivo in the rat“. Blood 75, Nr. 1 (01.01.1990): 74–81. http://dx.doi.org/10.1182/blood.v75.1.74.74.

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Abstract The relationship between the bone marrow (BM) megakaryocyte and the circulating platelet was explored. Incremental changes in platelet count were made in rats by infusion of antiplatelet antibody or by platelet transfusion, and the response of megakaryocytes was measured by flow cytometry. Proportional changes in megakaryocyte ploidy were demonstrated: As the platelet count declined, ploidy increased; as the platelet count increased, ploidy decreased. Even moderate degrees of thrombocytopenia and thrombocytosis (48% and 177% of the normal platelet count) were associated with changes in ploidy. These changes were not the results of the technique used to alter the platelet count because reinfusion of platelets after 3 hours of thrombocytopenia prevented any ploidy change. These studies proved that the circulating platelet and the megakaryocyte constitute a classic feedback loop whose activity can be measured by the degree of ploidization of the megakaryocyte. The minimal duration of thrombocytopenia necessary to promote megakaryocyte ploidy changes was approximately 10 hours. Using a BM culture assay, we identified a plasma factor which induced alterations in megakaryocyte ploidy and whose level is inversely proportional to the platelet count.

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Kuter, DJ, und RD Rosenberg. „Regulation of megakaryocyte ploidy in vivo in the rat“. Blood 75, Nr. 1 (01.01.1990): 74–81. http://dx.doi.org/10.1182/blood.v75.1.74.bloodjournal75174.

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The relationship between the bone marrow (BM) megakaryocyte and the circulating platelet was explored. Incremental changes in platelet count were made in rats by infusion of antiplatelet antibody or by platelet transfusion, and the response of megakaryocytes was measured by flow cytometry. Proportional changes in megakaryocyte ploidy were demonstrated: As the platelet count declined, ploidy increased; as the platelet count increased, ploidy decreased. Even moderate degrees of thrombocytopenia and thrombocytosis (48% and 177% of the normal platelet count) were associated with changes in ploidy. These changes were not the results of the technique used to alter the platelet count because reinfusion of platelets after 3 hours of thrombocytopenia prevented any ploidy change. These studies proved that the circulating platelet and the megakaryocyte constitute a classic feedback loop whose activity can be measured by the degree of ploidization of the megakaryocyte. The minimal duration of thrombocytopenia necessary to promote megakaryocyte ploidy changes was approximately 10 hours. Using a BM culture assay, we identified a plasma factor which induced alterations in megakaryocyte ploidy and whose level is inversely proportional to the platelet count.

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Gatarira, Cobes, Lucia Sládeková, Alžběta Němečková, Denisa Šimoníková, Rajneesh Paliwal, Asrat Asfaw, Michael Abberton et al. „Cytological and Molecular Characterization for Ploidy Determination in Yams (Dioscorea spp.)“. Agronomy 11, Nr. 10 (22.09.2021): 1897. http://dx.doi.org/10.3390/agronomy11101897.

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Yam (Dioscorea spp.) is a monocotyledonous herbaceous vine plant grown in the tropics and subtropics. It is a multi-species plant with varied intra- and interspecific ploidy levels. Of the 600 species, 11 are cultivated supporting the livelihood of over 300 million people. The paucity of information on ploidy and the genomic constitution is a significant challenge to the crop’s genetic improvement through crossbreeding. The objective of this study was to investigate the ploidy levels of 236 accessions across six cultivated and two wild species using chromosome counting, flow cytometry and genotyping-based ploidy determination methods. Results obtained from chromosome counting and genotyping-based ploidy determination were in agreement. In majority of the accessions, chromosome counting and flow cytometry were congruent, allowing future rapid screening of ploidy levels using flow cytometry. Among cultivated accessions, 168 (71%) were diploid, 50 (21%) were triploid, and 12 (5%) were tetraploid. Two wild species included in the study were diploids. Resolution of ploidy level in yams offers opportunities for implementing successful breeding programmes through intra- and interspecific hybridization.

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Hanušová, Kristýna, Martin Čertner, Tomáš Urfus, Petr Koutecký, Jiří Košnar, Carl J. Rothfels, Vlasta Jarolímová, Jan Ptáček und Libor Ekrt. „Widespread co-occurrence of multiple ploidy levels in fragile ferns (Cystopteris fragilis complex; Cystopteridaceae) probably stems from similar ecology of cytotypes, their efficient dispersal and inter-ploidy hybridization“. Annals of Botany 123, Nr. 5 (12.12.2018): 845–55. http://dx.doi.org/10.1093/aob/mcy219.

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Abstract Background and Aims Polyploidy has played an important role in the evolution of ferns. However, the dearth of data on cytotype diversity, cytotype distribution patterns and ecology in ferns is striking in comparison with angiosperms and prevents an assessment of whether cytotype coexistence and its mechanisms show similar patterns in both plant groups. Here, an attempt to fill this gap was made using the ploidy-variable and widely distributed Cystopteris fragilis complex. Methods Flow cytometry was used to assess DNA ploidy level and monoploid genome size (Cx value) of 5518 C. fragilis individuals from 449 populations collected over most of the species’ global distributional range, supplemented with data from 405 individuals representing other related species from the complex. Ecological preferences of C. fragilis tetraploids and hexaploids were compared using field-recorded parameters and database-extracted climate data. Key Results Altogether, five different ploidy levels (2x, 4x, 5x, 6x, 8x) were detected and three species exhibited intraspecific ploidy-level variation: C. fragilis, C. alpina and C. diaphana. Two predominant C. fragilis cytotypes, tetraploids and hexaploids, co-occur over most of Europe in a diffuse, mosaic-like pattern. Within this contact zone, 40 % of populations were mixed-ploidy and most also contained pentaploid hybrids. Environmental conditions had only a limited effect on the distribution of cytotypes. Differences were found in the Cx value of tetraploids and hexaploids: between-cytotype divergence was higher in uniform-ploidy than in mixed-ploidy populations. Conclusions High ploidy-level diversity and widespread cytotype coexistence in the C. fragilis complex match the well-documented patterns in some angiosperms. While ploidy coexistence in C. fragilis is not driven by environmental factors, it could be facilitated by the perennial life-form of the species, its reproductive modes and efficient wind dispersal of spores. Independent origins of hexaploids and/or inter-ploidy gene flow may be expected in mixed-ploidy populations according to Cx value comparisons.

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Vinogradov, A. E., O. V. Anatskaya und B. N. Kudryavtsev. „Relationship of hepatocyte ploidy levels with body size and growth rate in mammals“. Genome 44, Nr. 3 (01.06.2001): 350–60. http://dx.doi.org/10.1139/g01-015.

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To elucidate possible causes of the elevation of genome number in somatic cells, hepatocyte ploidy levels were measured cytofluorimetrically and related to the organismal parameters (body size, postnatal growth rate, and postnatal development type) in 53 mammalian species. Metabolic scope (ratio of maximal metabolic rate to basal metabolic rate) was also included in 23 species. Body masses ranged 105 times, and growth rate more than 30 times. Postnatal growth rate was found to have the strongest effect on the hepatocyte ploidy. At a fixed body mass the growth rate closely correlates (partial correlation analysis) with the cell ploidy level (r = 0.85, P < 106), whereas at a fixed growth rate body mass correlates poorly with ploidy level (r = 0.38, P < 0.01). The mature young (precocial mammals) of the species have, on average, a higher cell ploidy level than the immature-born (altricial) animals. However, the relationship between precocity of young and cell ploidy levels disappears when the influences of growth rate and body mass are removed. Interspecies variability of the hepatocyte ploidy levels may be explained by different levels of competition between the processes of proliferation and differentiation in cells. In turn, the animal differences in the levels of this competition are due to differences in growth rate. A high negative correlation between the hepatocyte ploidy level and the metabolic scope indicates a low safety margin of organs with a high number of polyploid cells. This fact allows us to challenge a common opinion that increasing ploidy enhances the functional capability of cells or is necessary for cell differentiation. Somatic polyploidy can be considered a "cheap" solution of growth problems that appear when an organ is working at the limit of its capabilities.Key words: genome number, somatic polyploidy, nuclear ploidy, multinuclearity, metabolic scope.

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Zubaidah, Siti. „TIPE SITOLOGI DUA SPESIES PTERIS DALAM HUBUNGANNYA DENGAN KETINGGIAN TEMPA“. Berkala Penelitian Hayati 7, Nr. 1 (31.12.2001): 25–28. http://dx.doi.org/10.23869/bphjbr.7.1.20013.

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A cytological study of the two species of Pteris (Pteris biaurita and Pteris tripartita) growing around Malang was carried out. A hypothesis stated that ploidy was enchanched by cold weather. Those study want to find out the correlation between the altitude (with different temperatures) and ploidy of the two species. Cytological type and ploidy examined by chromosome number counting, using standart squash method. The result of this research showed that Pteris biaurita and Pteris tripartite have two cytotypes, 2n= 58 (2x or diploid) and 2n= 116 (4x or tetraploid). There was no correlation between the ploidy level of Pteris biaurita and the altitude, but the ploidy level of Pteris tripartite apt to be raise in higher altitude.

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Liddell, Luke G., William G. Lee, Esther E. Dale, Heidi M. Meudt und Nicholas J. Matzke. „Pioneering polyploids: the impact of whole-genome duplication on biome shifting in New Zealand Coprosma (Rubiaceae) and Veronica (Plantaginaceae)“. Biology Letters 17, Nr. 9 (September 2021): 20210297. http://dx.doi.org/10.1098/rsbl.2021.0297.

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The role of whole-genome duplication (WGD) in facilitating shifts into novel biomes remains unknown. Focusing on two diverse woody plant groups in New Zealand, Coprosma (Rubiaceae) and Veronica (Plantaginaceae), we investigate how biome occupancy varies with ploidy level, and test the hypothesis that WGD increases the rate of biome shifting. Ploidy levels and biome occupancy (forest, open and alpine) were determined for indigenous species in both clades. The distribution of low-ploidy ( Coprosma : 2 x , Veronica : 6 x ) versus high-ploidy ( Coprosma : 4–10 x , Veronica : 12–18 x ) species across biomes was tested statistically. Estimation of the phylogenetic history of biome occupancy and WGD was performed using time-calibrated phylogenies and the R package BioGeoBEARS. Trait-dependent dispersal models were implemented to determine support for an increased rate of biome shifting among high-ploidy lineages. We find support for a greater than random portion of high-ploidy species occupying multiple biomes. We also find strong support for high-ploidy lineages showing a three- to eightfold increase in the rate of biome shifts. These results suggest that WGD promotes ecological expansion into new biomes.

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Suda, Jan, Anna Krahulcová, Pavel Trávníek und František Krahulec. „Ploidy level versus DNA ploidy level: an appeal for consistent terminology“. TAXON 55, Nr. 2 (Mai 2006): 447–50. http://dx.doi.org/10.2307/25065591.

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Wan, Y., L. M. McMurphy, A. L. Rayburn und J. M. Widholm. „Ploidy levels of plants regenerated from mixed ploidy maize callus cultures“. In Vitro Cellular & Developmental Biology - Plant 28, Nr. 2 (April 1992): 87–89. http://dx.doi.org/10.1007/bf02823024.

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Krois, Nicole R., Anvesh Cherukuri, Nikhil Puttagunta und Maurine Neiman. „Higher rate of tissue regeneration in polyploid asexual versus diploid sexual freshwater snails“. Biology Letters 9, Nr. 4 (23.08.2013): 20130422. http://dx.doi.org/10.1098/rsbl.2013.0422.

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Characterizing phenotypic differences between sexual and asexual organisms is a critical step towards understanding why sexual reproduction is so common. Because asexuals are often polyploid, understanding how ploidy influences phenotype is directly relevant to the study of sex and will provide key insights into the evolution of ploidy-level variation. The well-established association between genome size and cell cycle duration, evidence for a link between genome size and tissue regeneration rate and the growing body of research showing that ploidy influences growth rate and gene expression led us to hypothesize that healing and tissue regeneration might be affected by ploidy-level variation. We evaluated this hypothesis by measuring the rate of regeneration of antenna tissue of Potamopyrgus antipodarum , a New Zealand snail characterized by frequent coexistence between diploid sexuals and polyploid asexuals. Antennae of triploid and presumptive tetraploid asexuals regenerated more rapidly than the antennae of diploid sexuals, but regeneration rate did not differ between triploids and tetraploids. These results suggest either that ploidy elevation has nonlinear positive effects on tissue regeneration and/or that factors associated directly with reproductive mode affect regeneration rate more than ploidy level. The results of this study also indicate that the lower ploidy of sexual P. antipodarum is unlikely to confer advantages associated with more rapid regeneration.

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Tomaszewska, Paulina, Till K. Pellny, Luis M. Hernández, Rowan A. C. Mitchell, Valheria Castiblanco, José J. de Vega, Trude Schwarzacher und Pat (J S. ). Heslop-Harrison. „Flow Cytometry-Based Determination of Ploidy from Dried Leaf Specimens in Genomically Complex Collections of the Tropical Forage Grass Urochloa s. l.“ Genes 12, Nr. 7 (23.06.2021): 957. http://dx.doi.org/10.3390/genes12070957.

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Urochloa (including Brachiaria, Megathyrus and some Panicum) tropical grasses are native to Africa and are now, after selection and breeding, planted worldwide, particularly in South America, as important forages with huge potential for further sustainable improvement and conservation of grasslands. We aimed to develop an optimized approach to determine ploidy of germplasm collection of this tropical forage grass group using dried leaf material, including approaches to collect, dry and preserve plant samples for flow cytometry analysis. Our methods enable robust identification of ploidy levels (coefficient of variation of G0/G1 peaks, CV, typically <5%). Ploidy of some 348 forage grass accessions (ploidy range from 2x to 9x), from international genetic resource collections, showing variation in basic chromosome numbers and reproduction modes (apomixis and sexual), were determined using our defined standard protocol. Two major Urochloa agamic complexes are used in the current breeding programs at CIAT and EMBRAPA: the ’brizantha’ and ’humidicola’ agamic complexes are variable, with multiple ploidy levels. Some U. brizantha accessions have odd level of ploidy (5x), and the relative differences in fluorescence values of the peak positions between adjacent cytotypes is reduced, thus more precise examination of this species is required. Ploidy measurement of U. humidicola revealed aneuploidy.

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Osterheld, Maria‐Chiara, Liette Caron, Mireille Demierre, Ricardo Laurini und F. T. Bosman. „DNA-Ploidy in Advanced Gastric Carcinoma is Less Heterogeneous than in Early Gastric Cancer“. Analytical Cellular Pathology 26, Nr. 1-2 (01.01.2004): 21–29. http://dx.doi.org/10.1155/2004/219293.

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This analysis of DNA‐ploidy heterogeneity in advanced gastric carcinomas is consistent with the hypothesis of the emergence of a single aneuploid cell clone as a crucial mechanism in the progression from early gastric carcinoma to advanced gastric cancer. The prognostic value of DNA‐ploidy in gastric cancers has been a matter of controversy. Tumour DNA‐ploidy heterogeneity, the presence within the same tumour of multiple stemlines differing in DNA content, has been described in various tumours including gastric cancers. The occurrence of such heterogeneity has been accepted as an explanation for the divergent DNA‐ploidy results in this type of tumours. A previous study of early gastric cancers suggested that in pure diploid superficial carcinomas, genetic instability might lead to a cell clone which has undergone a ploidy shift and is more aggressive. If so, this would initially result in DNA‐ploidy heterogeneity. Proliferative dominance of the aneuploid clone could eventually evolve to a homogeneous aneuploid tumour. In order to test this hypothesis, we studied DNA‐aneuploidy and DNA‐ploidy heterogeneity in advanced gastric carcinomas. We performed DNA cytophotometry on multiple samples collected from 16 advanced gastric carcinomas and found 15 DNA‐aneuploid tumours (94%) and one diploid tumour. Multiple DNA‐stemlines were found in 4 cases (26%). Analysis of proliferative activity performed on the same samples revealed higher proliferation rate in DNA‐ploidy homogeneous tumours than in aneuploid heterogeneous tumours. Heterogeneous tumours did not overexpress p53. These results confirm that DNA‐aneuploidy is frequent in advanced gastric cancer and demonstrate that a majority of these aneuploid tumours are not DNA‐ploidy heterogeneous. Furthermore, the higher proliferative activity in homogeneous‐aneuploid carcinomas and their more frequent overexpression of p53 support the hypothesis that in gastric cancer tumour progression implies the development of a dominant and more aggressive (higher proliferative activity, p53 overexpression) aneuploid cell clone.

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Takes, Robert P., Roelof van Blommestein, Han H. J. M. van Krieken, Robert J. Baatenburg de Jong, Jo Hermans und Cees J. Cornelisse. „DNA Ploidy Status as a Prognostic Marker and Predictor of Lymph Node Metastasis in Laryngeal Carcinoma“. Annals of Otology, Rhinology & Laryngology 111, Nr. 11 (November 2002): 1015–20. http://dx.doi.org/10.1177/000348940211101112.

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In patients with laryngeal carcinoma, nodal metastasis, recurrence after radiotherapy, and prognosis are important factors in clinical decision-making. Parameters such as tumor stage are considered insufficient for predicting these important items. The DNA ploidy status of the tumor may be a useful additional marker. The DNA ploidy status of 38 laryngeal cancers was determined by flow cytometry. Correlations were studied with TNM stage, differentiation, survival rate, relapse risk, recurrence after radiotherapy, and nodal metastasis. A positive correlation of DNA ploidy status with the development of lymph node metastases was found for diploid and peridiploid versus aneuploid tumors (DNA index, <1.4 versus ≥1.4; p = .007). No correlation was found between ploidy status and recurrence after radiotherapy. The overall survival rate (p = .01), but not the disease-specific survival rate or the relapse risk, showed a correlation with the ploidy status. The DNA ploidy status may be a useful marker for metastatic behavior in head and neck squamous cell carcinoma and may therefore be helpful in decision-making concerning elective treatment of the neck.

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Milroy, Christopher M., Kenneth O. Devaney, Alfio Ferlito und Alessandra Rinaldo. „Role of DNA Measurements of Head and Neck Tumors“. Annals of Otology, Rhinology & Laryngology 106, Nr. 9 (September 1997): 801–4. http://dx.doi.org/10.1177/000348949710600919.

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The measurement of DNA ploidy has been used as a tool to try to determine the prognosis of many neoplasms. DNA ploidy can be determined by flow cytometry or image analysis of a tumor. In squamous carcinomas of the head and neck, a poorer prognosis has been associated with nondiploid tumors. Similar results have been obtained from studies of salivary gland neoplasms. The role of DNA ploidy as a provider of independent information has yet to be determined. With rarer head and neck tumors, measurement of tumor ploidy has yet to be established as a valuable adjunct to routine light microscopic study.

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