Zeitschriftenartikel: „Simulačný model“

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SEDLÁČEK, Michal. „SIMULATION MODELS AND POSSIBILITIES OF THEIR APPLICATION IN TEACHING TECHNICAL SUBJECTS IN THE CONTEXT OF INDUSTRIE 4.0“. Trends in Education 13, Nr. 1 (25.11.2020): 12–19. http://dx.doi.org/10.5507/tvv.2020.002.

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de Paula, Alexandre Silva, und Carlos Barreto. „Potential Distribution of Nysius simulans (Hemiptera: Lygaeidae) in Soybean Crops in South America Under Current and Future Climate“. Journal of Economic Entomology 113, Nr. 4 (14.05.2020): 1702–10. http://dx.doi.org/10.1093/jee/toaa089.

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Abstract Nysius simulans (Stål) is a suctorial, fluid feeding herbivore that can transmit toxins and spread pathogens via saliva and is an economically important pest for soybean in South America. Currently, N. simulans in soybean is predominantly found in Argentina, but future changes in the distribution from both dispersal and range shifts due to climate change may affect soybean cultivation in southern South America. We developed a species distribution model to examine the distribution range of N. simulans. We compared the potential distribution of N. simulans under current and future projected climatic conditions in order to identify future areas of natural occurrence with ecological niche models using Maxent. Current records of N. simulans show that while the species is present in Argentina, and some areas of Brazil, Paraguay, Peru, and Uruguay, our models suggest that many new suitable areas will be available for N. simulans under climate change including other regions of Argentina, and southern Chile. Our results also predict potential future range shifts and distributions into Bolivia, but not Peru nor Brazil. In our model, seasonal trends in temperature were shown to have the greatest contribution to the potential distribution, whereas isothermality (i.e., temperature variability) was correlated to potential future distribution ranges. We conclude that current populations of N. simulans may be expanding its distribution range by diffusion (i.e., range expansion over generations at the margins of populations), and regions with potential future N. simulans distribution should be closely monitored.

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Pitoňák, Jaroslav, und Miroslav Galbavý. „The use of simulation models for the design of friction shifting elements used in planetary transmissions“. Journal of Middle European Construction and Design of Cars 9, Nr. 2 (01.11.2011): 1–7. http://dx.doi.org/10.2478/v10138-011-0007-z.

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ZHRNUTIE Otazka projektovania a navrhovania transmisii nadobuda pri sučasnom využivani softverovych prostriedkov nove rozmery. Vypočtovy system Matlab ponuka široke možnosti pri vytvarani a skumani novych riešeni v prostredi matematickych modelov. Jeho sučasťou je aj modul SimDriveline, ktory nadobuda vyznam hlavne čo sa tyka zjednodušenia zostavenia modelu transmisie, vytvarania vzťahov medzi objektmi modelu, nazornosti, prehľadnosti, prezentacie vysledkov a pod. V tomto pripade sa však jedna o simulačne modely fyzikalne, ktore umožňuju modelovať spravanie sa systemu priamo popisom jeho fyzikalnej štruktury. Taketo simulačne modely nachadzaju využitie pri navrhoch roznych časti pohonov, napriklad i radiacich prvkov planetovych prevodoviek - spojok a bŕzd. Pomocou simulacii možno sledovať priebehy zakladnych veličin, teda aj spravanie sa jednotlivych členov mechanizmu, čo umožňuje značnou mierou prispieť k optimalnemu riešeniu transmisie.

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Kocina, Ondřej J. „Simulační model výrobního procesu - malování a smaltování skla“. Acta Oeconomica Pragensia 15, Nr. 6 (01.10.2007): 107–26. http://dx.doi.org/10.18267/j.aop.512.

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Žák, Zdeněk, Oldřich Vítek und Jan Macek. „Application of a Radial Turbine 1-D Model“. Journal of Middle European Construction and Design of Cars 11, Nr. 1 (01.06.2013): 1–8. http://dx.doi.org/10.2478/mecdc-2013-0001.

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Shrnutí Članek, na několika přikladech, popisuje simulace s využitim 1-D modelu radialni turbiny turbodmychadla. Cilem je popsat současny stav a ukazat potencial 1-D přistupu v oblasti modelovani turbodmychadla. Pro možnost testovani modelů turbiny a kompresoru byly vyvinuty rozmanite simulačni nastroje. Model turbinoveho testovaciho stavu umožňuje provozovat turbinu v široke provozni oblasti. Model zkušebniho stavu turbodmychadel se spalovaci komorou je vhodny pro přiřazeni kompresoru turbině. Članek uzaviraji vysledky fungovani modelu turbiny ve spojeni s modelem virtualniho čtyřtaktniho zažehoveho motoru.

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Hvězda, Jiří. „A Multi-Zone Model of the Combustion Process in an Si Engine as an External Cylinder of the Gt-Power Simulation Tool“. Journal of Middle European Construction and Design of Cars 12, Nr. 3 (01.12.2014): 8–14. http://dx.doi.org/10.2478/mecdc-2014-0010.

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Shrnutí Příspěvek představuje obecnou proceduru týkající se implementace uživatelského modelu jako externího válce simulačního nástroje GT-Power. Konkrétně, vyvinutý vícezónový model vysokotlaké části termodynamického cyklu čtyřdobého spalovacího motoru je zde použit jako přizpůsobený simulační kód pro zajištění výpočtů souvisejících s chemickou transformací spalování, přestupem tepla a odpovídajícími stavovými veličinami. Jsou zde prezentovány vybrané technické podrobnosti a výsledky tohoto propojení

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Wall, Jeffrey D., Peter Andolfatto und Molly Przeworski. „Testing Models of Selection and Demography inDrosophila simulans“. Genetics 162, Nr. 1 (01.09.2002): 203–16. http://dx.doi.org/10.1093/genetics/162.1.203.

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AbstractWe analyze patterns of nucleotide variability at 15 X-linked loci and 14 autosomal loci from a North American population of Drosophila simulans. We show that there is significantly more linkage disequilibrium on the X chromosome than on chromosome arm 3R and much more linkage disequilibrium on both chromosomes than expected from estimates of recombination rates, mutation rates, and levels of diversity. To explore what types of evolutionary models might explain this observation, we examine a model of recurrent, nonoverlapping selective sweeps and a model of a recent drastic bottleneck (e.g., founder event) in the demographic history of North American populations of D. simulans. The simple sweep model is not consistent with the observed patterns of linkage disequilibrium nor with the observed frequencies of segregating mutations. Under a restricted range of parameter values, a simple bottleneck model is consistent with multiple facets of the data. While our results do not exclude some influence of selection on X vs. autosome variability levels, they suggest that demography alone may account for patterns of linkage disequilibrium and the frequency spectrum of segregating mutations in this population of D. simulans.

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Russell, Renee L., und Reid A. Peterson. „Boehmite Dissolution Model Based on Simulant Data“. Industrial & Engineering Chemistry Research 49, Nr. 10 (19.05.2010): 4542–45. http://dx.doi.org/10.1021/ie901841g.

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Mládek, Arnošt, Martin Vokurka und Jiří Kofránek. „MATEMATICKÝ MODEL REGULACE ŽELEZA V ORGANISMU“. Medsoft 2020 32, Nr. 1 (06.03.2020): 47–54. http://dx.doi.org/10.35191/medsoft_2020_1_32_47_54.

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S využitím námi vyvinutého vývojového nástroje BodyLight.js byla vytvořena výuková simulační aplikace, která interaktivní formou vysvětluje metabolismus železa v lidském organismu. V pozadí aplikace je matematický model vytvořený v jazyce Modelica. Náš vývojový nástroj umožnil propojit matematický model s grafickými objekty a výukovým textem a vygenero-vat výukovou aplikaci do standardizovaného HTML souboru, který je možné spouštět v běžném internetovém prohlížeči na počítači, tabletu nebo chytrém telefonu bez nutnosti instalace jakékoliv aplikace nebo rozšíření. Interaktivní aplikace se stane komplementem standardní výuky regulace železa v rámci kurzu patologické fyziologie.

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Kliman, Richard M., Peter Andolfatto, Jerry A. Coyne, Frantz Depaulis, Martin Kreitman, Andrew J. Berry, James McCarter, John Wakeley und Jody Hey. „The Population Genetics of the Origin and Divergence of theDrosophila simulansComplex Species“. Genetics 156, Nr. 4 (01.12.2000): 1913–31. http://dx.doi.org/10.1093/genetics/156.4.1913.

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AbstractThe origins and divergence of Drosophila simulans and close relatives D. mauritiana and D. sechellia were examined using the patterns of DNA sequence variation found within and between species at 14 different genes. D. sechellia consistently revealed low levels of polymorphism, and genes from D. sechellia have accumulated mutations at a rate that is ∼50% higher than the same genes from D. simulans. At synonymous sites, D. sechellia has experienced a significant excess of unpreferred codon substitutions. Together these observations suggest that D. sechellia has had a reduced effective population size for some time, and that it is accumulating slightly deleterious mutations as a result. D. simulans and D. mauritiana are both highly polymorphic and the two species share many polymorphisms, probably since the time of common ancestry. A simple isolation speciation model, with zero gene flow following incipient species separation, was fitted to both the simulans/mauritiana divergence and the simulans/sechellia divergence. In both cases the model fit the data quite well, and the analyses revealed little evidence of gene flow between the species. The exception is one gene copy at one locus in D. sechellia, which closely resembled other D. simulans sequences. The overall picture is of two allopatric speciation events that occurred quite near one another in time.

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Metzger, Philip T., und Daniel T. Britt. „Model for asteroid regolith to guide simulant development“. Icarus 350 (November 2020): 113904. http://dx.doi.org/10.1016/j.icarus.2020.113904.

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Farrell, Svetlana, H. Brian Halsall und William R. Heineman. „BacillusglobigiiBugbeads: A Model Simulant of a Bacterial Spore“. Analytical Chemistry 77, Nr. 2 (Januar 2005): 549–55. http://dx.doi.org/10.1021/ac049156y.

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Trumel, H., A. Dragon und A. Fanget. „A finite-strain model for an explosive simulant“. Le Journal de Physique IV 04, Nr. C8 (September 1994): C8–559—C8–564. http://dx.doi.org/10.1051/jp4:1994887.

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Zeng, L. W., und R. S. Singh. „The genetic basis of Haldane's rule and the nature of asymmetric hybrid male sterility among Drosophila simulans, Drosophila mauritiana and Drosophila sechellia.“ Genetics 134, Nr. 1 (01.05.1993): 251–60. http://dx.doi.org/10.1093/genetics/134.1.251.

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Abstract Haldane's rule (i.e., the preferential hybrid sterility and inviability of heterogametic sex) has been known for 70 years, but its genetic basis, which is crucial to the understanding of the process of species formation, remains unclear. In the present study, we have investigated the genetic basis of hybrid male sterility using Drosophila simulans, Drosophila mauritiana and Drosophila sechellia. An introgression of D. sechellia Y chromosome into a fairly homogenous background of D. simulans did not show any effect of the introgressed Y on male sterility. The substitution of D. simulans Y chromosome into D. sechellia, and both reciprocal Y chromosome substitutions between D. simulans and D. mauritiana were unsuccessful. Introgressions of cytoplasm between D. simulans and D. mauritiana (or D. sechellia) also did not have any effect on hybrid male sterility. These results rule out the X-Y interaction hypothesis as a general explanation of Haldane's rule in this species group and indicate an involvement of an X-autosome interaction. Models of symmetrical and asymmetrical X-autosome interaction have been developed which explain the Y chromosome substitution results and suggest that evolution of interactions between different genetic elements in the early stages of speciation is more likely to be of an asymmetrical nature. The model of asymmetrical X-autosome interaction also predicts that different sets of interacting genes may be involved in different pairs of related species and can account for the observation that hybrid male sterility in many partially isolated species is often nonreciprocal or unidirectional.

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Zheng, Hu, und Yu Huang. „Model tests on flow slide of lunar regolith simulant“. Environmental Earth Sciences 73, Nr. 8 (16.10.2014): 4853–59. http://dx.doi.org/10.1007/s12665-014-3767-7.

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Armbruster, Georg FJ. „Temperature-based variation of rRNA secondary structure models: a case study in the insect Drosophila simulans, the land snail Isabellaria adriani, and the crustacean Daphnia pulex“. Canadian Journal of Zoology 79, Nr. 2 (01.02.2001): 334–45. http://dx.doi.org/10.1139/z00-205.

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The influence of a temperature default on ribosomal RNA (rRNA) secondary structure models was studied with the "Mfold" energy-optimization program. Folding models of the internal transcribed spacer (ITS) 1 rRNA for both Drosophila simulans (Insecta) and Isabellaria adriani (Gastropoda) were generated at two different temperatures. The folding models are compared with the models previously shown for the ITS-1 of D. melanogaster Oregon R strain and I. adriani. A search for phylogenetically informative ITS-1 folding motifs was conducted for D. simulans. In I. adriani, a new approach for ITS-1 secondary structure analyses is suggested. The paper also elucidates results inferred from three energy-optimizing programs (Mfold, GeneBee, and STAR). These three folding programs give different information on the structure and free energy of a ITS-1 rRNA molecule. Furthermore, secondary-structure models of the small subunit (ssu) rRNA of Daphnia pulex (Crustacea: Cladocera) were investigated. The ssu rRNA molecule is usually folded according to alignment information. Here, ssu folding patterns are computed with Mfold using two temperature conditions. The two Mfold models are compared with the alignment model previously suggested for D. pulex. Three cladoceran-specific motifs and a short stem motif within the ssu rRNA of eukaryotes are discussed with respect to structure and phylogenetic information.

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Russell, R. L., J. M. Billing, H. D. Smith und R. A. Peterson. „Validation of Ultrafilter Performance Model Based on Systematic Simulant Evaluation“. Industrial & Engineering Chemistry Research 48, Nr. 22 (18.11.2009): 10077–86. http://dx.doi.org/10.1021/ie901042w.

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Low, Siew Cheng, Nicky Eshtiaghi, Paul Slatter, Jean-Christophe Baudez und Rajarathinam Parthasarathy. „Mixing characteristics of sludge simulant in a model anaerobic digester“. Bioprocess and Biosystems Engineering 39, Nr. 3 (06.01.2016): 473–83. http://dx.doi.org/10.1007/s00449-015-1530-4.

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Liu, Susu, C. Xu, Y. Wen, G. Li und J. Zhou. „Assessment of bullet effectiveness based on a human vulnerability model“. Journal of the Royal Army Medical Corps 164, Nr. 3 (25.12.2017): 172–78. http://dx.doi.org/10.1136/jramc-2017-000855.

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IntroductionPenetrating wounds from explosively propelled fragments and bullets are the most common causes of combat injury. There is a requirement to assess the potential effectiveness of bullets penetrating human tissues in order to optimise preventive measures and wound trauma management.MethodsAn advanced voxel model based on the Chinese Visible Human data was built. A digital human vulnerability model was established in combination with wound reconstruction and vulnerability assessment rules, in which wound penetration profiles were obtained by recreating the penetration of projectiles into ballistic gelatin. An effectiveness evaluation method of bullet penetration using the Abbreviated Injury Scale (AIS) was developed and solved using the Monte Carlo sampling method.ResultsThe effectiveness of rifle bullets was demonstrated to increase with increasing velocity in the range of 300–700 m/s. When imparting the same energy, the effectiveness of the 5.56 mm bullet was higher than the 7.62 mm bullet in this model.ConclusionsThe superimposition of simulant penetration profiles produced from ballistic gelatin simulant has been used to predict wound tracts in damaged tissues. The authors recognise that determining clinical effectiveness based on the AIS scores alone without verification of outcome by review of clinical hospital records means that this technique should be seen more as a manner of comparing the effectiveness of bullets than an injury prediction model.

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Presgraves, Daven C. „A Fine-Scale Genetic Analysis of Hybrid Incompatibilities in Drosophila“. Genetics 163, Nr. 3 (01.03.2003): 955–72. http://dx.doi.org/10.1093/genetics/163.3.955.

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Abstract The sterility and inviability of species hybrids is thought to evolve by the accumulation of genes that cause generally recessive, incompatible epistatic interactions between species. Most analyses of the loci involved in such hybrid incompatibilities have suffered from low genetic resolution. Here I present a fine-resolution genetic screen that allows systematic counting, mapping, and characterizing of a large number of hybrid incompatibility loci in a model genetic system. Using small autosomal deletions from D. melanogaster and a hybrid rescue mutation from D. simulans, I measured the viability of hybrid males that are simultaneously hemizygous for a small region of the D. simulans autosomal genome and hemizygous for the D. melanogaster X chromosome. These hybrid males are exposed to the full effects of any recessive-recessive epistatic incompatibilities present in these regions. A screen of ∼70% of the D. simulans autosomal genome reveals 20 hybrid-lethal and 20 hybrid-semilethal regions that are incompatible with the D. melanogaster X. In further crosses, I confirm the epistatic nature of hybrid lethality by showing that all of the incompatibilities are rescued when the D. melanogaster X is replaced with a D. simulans X. Combined with information from previous studies, these results show that the number of recessive incompatibilities is approximately eightfold larger than the number of dominant ones. Finally, I estimate that a total of ∼191 hybrid-lethal incompatibilities separate D. melanogaster and D. simulans, indicating extensive functional divergence between these species’ genomes.

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Akashi, Hiroshi. „Molecular Evolution Between Drosophila melanogaster and D. simulans Reduced Codon Bias, Faster Rates of Amino Acid Substitution, and Larger Proteins in D. melanogaster“. Genetics 144, Nr. 3 (01.11.1996): 1297–307. http://dx.doi.org/10.1093/genetics/144.3.1297.

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Abstract Both natural selection and mutational biases contribute to variation in codon usage bias within Drosophila species. This study addresses the cause of codon bias differences between the sibling species, Drosophila melanogaster and D. simulans. Under a model of mutation-selection-drift, variation in mutational processes between species predicts greater base composition differences in neutrally evolving regions than in highly biased genes. Variation in selection intensity, however, predicts larger base composition differences in highly biased loci. Greater differences in the G+C content of 34 coding regions than 46 intron sequences between D. melanogaster and D. simulans suggest that D. melanogaster has undergone a reduction in selection intensity for codon bias. Computer simulations suggest at least a fivefold reduction in Nes at silent sites in this lineage. Other classes of molecular change show lineage effects between these species. Rates of amino acid substitution are higher in the D. melanogaster lineage than in D. simulans in 14 genes for which outgroup sequences are available. Surprisingly, protein sizes are larger in D. melanogaster than in D. simulans in the 34 genes compared between the two species. A substantial fraction of silent, replacement, and insertion/deletion mutations in coding regions may be weakly selected in Drosophila.

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Ishihara, Shingo, Ko-ichiro Ohno, Hirokazu Konishi, Takashi Watanabe, Shungo Natsui, Hiroshi Nogami und Junya Kano. „Prediction of Softening Behavior of Simulant Sinter Ore by ADEM-SPH Model“. ISIJ International 60, Nr. 7 (15.07.2020): 1545–50. http://dx.doi.org/10.2355/isijinternational.isijint-2020-078.

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MOUNTFORT, KATRINA, JANET KELLY, SUE M. JICKELLS und LAURENCE CASTLE. „A Critical Comparison of Four Test Methods for Determining Overall and Specific Migration from Microwave Susceptor Packaging“. Journal of Food Protection 59, Nr. 5 (01.05.1996): 534–40. http://dx.doi.org/10.4315/0362-028x-59.5.534.

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Four approaches for testing for overall migration and specific chemical migration from microwave susceptors were evaluated. The methods used olive oil as a conventional liquid food simulant, a semisolid simulant of olive oil and water absorbed onto diatomaceous earth, Tenax™ as a dry simulant, and compositional analysis of the susceptor by ASTM methods. The different methods were tested on five susceptor types used for the packaging of pizza, potato chips (French fries), pasty, popcorn, and a curry. For the comparison, the susceptor materials were impregnated with model substances as migration markers covering a range of molecular weight, volatility and polarity. Levels of specific migration (SM) and overall migration (OM) were determined using the four test methods, which were then evaluated on the basis of their ease and reproducibility of use along with the agreement between specific migration levels into simulants compared with migration into foods. There were severe problems with olive oil as a conventional liquid simulant as it was absorbed by the susceptor and made SM and OM measurements difficult. Humidity conditioning the susceptor for OM was a further difficulty with olive oil. Oil absorption was also a problem using the semisolid simulant, with OM being untried using this approach. The ASTM methods were found to be time-consuming, although the results for SM were similar to those obtained for foods. Overall, however, using Tenax was the preferred method for migration testing of susceptors. It allowed easy measurement of both OM and SM. SM values were generally much higher than for foods, however, and a reduction factor would be required for control of regulated ingredients. For other substances, such as thermal degradation products, a threshold of regulation approach applied to the Tenax extract would be a simple and effective control measure.

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Kofránek, Jiří, Filp Ježek, Jan Šilar, Arnošt Mládek, Marek Mateják und Tomáš Kulhánek. „NOVÁ GENERACE ELEKTRONICKÝCH UČEBNIC SE SIMULAČNÍM JÁDREM.“ Medsoft 2020 32, Nr. 1 (06.03.2020): 63–72. http://dx.doi.org/10.35191/medsoft_2020_1_32_63_72.

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V poslední době se objevily nové elektronické učebnice, propo-jující hypertext, simulační modely a interaktivní grafiku (řízenou modelem na pozadí), které přinášejí zcela nové možnosti pro vysvětlování složitě propojených regulačních vztahů zejmé-na v medicíně. Jsou to většinou aplikace typu client-server, kdy celá aplikace běží na serveru a uživatel se k ní připojuje většinou pomocí internetového prohlížeče či jiného dediko-vaného rozhraní. Existují také aplikace které pracují lokálně na klientském počítači nebo tabletu. My jsme vyvinuli technologii Bodylight.js, která umožňuje tvorbu obdobných výukových aplikací s interaktivními simulátory spustitelnými přímo v inter-netovém prohlížeči na jakékoli platformě či operačním systému (notebooku, tabletu či chytrém telefonu), o níž jsme referovali v loňském ročníku MEDSOFT, V tomto sdělení tuto technologii popíšeme podrobněji a ukážeme i první aplikace.

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Huang, Bo, Zhujin Jiang, Peng Lin und Daosheng Ling. „Research on Impact Process of Lander Footpad against Simulant Lunar Soils“. Shock and Vibration 2015 (2015): 1–24. http://dx.doi.org/10.1155/2015/658386.

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The safe landing of a Moon lander and the performance of the precise instruments it carries may be affected by too heavy impact on touchdown. Accordingly, landing characteristics have become an important research focus. Described in this paper are model tests carried out using simulated lunar soils of different relative densities (called “simulant” lunar soils below), with a scale reduction factor of 1/6 to consider the relative gravities of the Earth and Moon. In the model tests, the lander was simplified as an impact column with a saucer-shaped footpad with various impact landing masses and velocities. Based on the test results, the relationships between the footpad peak feature responses and impact kinetic energy have been analyzed. Numerical simulation analyses were also conducted to simulate the vertical impact process. A 3D dynamic finite element model was built for which the material parameters were obtained from laboratory test data. When compared with the model tests, the numerical model proved able to effectively simulate the dynamic characteristics of the axial forces, accelerations, and penetration depths of the impact column during landing. This numerical model can be further used as required for simulating oblique landing impacts.

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Hvězda, Jiří. „Multi-Zone Models of Combustion and Heat Transfer Processes in SI Engines“. Journal of Middle European Construction and Design of Cars 10, Nr. 2 (01.11.2012): 14–22. http://dx.doi.org/10.2478/v10138-012-0008-6.

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Shrnutí Tato práce představuje sadu nově vyvinutých nástrojů implementovatelných do komplexních kódů pro simulaci spalovacích motorů pro zajištění výpočtů týkajících se vysokotlaké části termodynamického cyklu čtyřdobého zážehového motoru. Tento více-zónový simulační nástroj pracuje na základě jednoduché kvazi-dimenzionální metody reflektující reálnou geometrii spalovacího prostoru a používá specifický přístup k popisu chemické transformace složek. V případech abnormálně rychlých chemických reakcí je klasické kinetické schéma adaptivně kombinováno s flexibilní metodou chemické rovnováhy pro zlepšení numerických vlastností soustavy rovnic. Reálná 3-D geometrie spalovacího prostoru je zohledňována pomocí předem vytvořených geometrických charakteristik. Je zde prezentován nový univerzální nástroj zajišťující tato data. Nový kód má schopnost pracovat v prediktivním stejně jako inverzním módu. Vybrané výsledky týkající se obou těchto režimů jsou prezentovány v závěru příspěvku.

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Garnier, Laurence, Jean-Christophe Gaudin, Paul Bensadoun, Isabelle Rebillat und Yannick Morel. „Real-Time PCR Assay for Detection of a New Simulant for Poxvirus Biothreat Agents“. Applied and Environmental Microbiology 75, Nr. 6 (23.01.2009): 1614–20. http://dx.doi.org/10.1128/aem.02120-08.

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ABSTRACT Research and financial efforts spent on biodefense technologies highlight the current concern for biothreat event preparedness. Nonhazardous but relevant “simulant” microorganisms are typically used to simplify technological developments, testing, and staff training. The bacteriophage MS2, a small RNA virus, is classically used as the reference simulant for biothreat viruses within the biodefense community. However, variola virus, considered a major threat, displays very different features (size, envelope, and double-stranded DNA genome). The size parameter is critical for aerosol sampling, detection, and protection/filtration technologies. Therefore, a panel of relevant simulants should be used to cover the diversity of biothreat agents. Thus, we investigated a new virus model, the Cydia pomonella granulovirus (baculovirus), which is currently used as a biopesticide. It displays a size similar to that of poxviruses, is enveloped, and contains double-stranded DNA. To provide a molecular tool to detect and quantify this model virus, we developed an assay based on real-time PCR, with a limit of detection ranging from roughly 10 to a few tens of target copies per μl according to the sample matrix. The specificity of the assay against a large panel of potential cross-reactive microorganisms was checked, and the suitability of the assay for environmental samples, especially aerosol studies, was determined. In conclusion, we suggest that our PCR assay allows Cydia pomonella granulovirus to be used as a simulant for poxviruses. This assay may also be useful for environmental or crop treatment studies.

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Chanda, Arnab, und Rebecca Graeter. „Human Skin-Like Composite Materials for Blast Induced Injury Mitigation“. Journal of Composites Science 2, Nr. 3 (01.08.2018): 44. http://dx.doi.org/10.3390/jcs2030044.

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Armors and military grade personal protection equipment (PPE) materials to date are bulky and are not designed to effectively mitigate blast impacts. In the current work, a human skin-like castable simulant material was developed and its blast mitigation characteristics (in terms of induced stress reduction at the bone and muscles) were characterized in the presence of composite reinforcements. The reinforcement employed was Kevlar 129 (commonly used in advanced combat helmets), which was embedded within the novel skin simulant material as the matrix and used to cover a representative extremity based human skin, muscle and bone section finite element (FE) model. The composite variations tested were continuous and short-fiber types, lay-ups (0/0, 90/0, and 45/45 orientations) and different fiber volume fractions. From the analyses, the 0/0 continuous fiber lay-up with a fiber volume fraction close to 0.1 (or 10%) was found to reduce the blast-induced dynamic stresses at the bone and muscle sections by 78% and 70% respectively. These findings indicate that this novel skin simulant material with Kevlar 129 reinforcement, with further experimental testing, may present future opportunities in blast resistant armor padding designing.

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Kradtap, Supaporn, C. Ajith Wijayawardhana, Kevin T. Schlueter, H. Brian Halsall und William R. Heineman. „“Bugbead”: an artificial microorganism model used as a harmless simulant for pathogenic microorganisms“. Analytica Chimica Acta 444, Nr. 1 (Oktober 2001): 13–26. http://dx.doi.org/10.1016/s0003-2670(01)01152-7.

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Jiang, Mingjing, Banglu Xi, Fabio V. De Blasio, Huayang Lei und De’an Sun. „Physical Model Tests of the Bearing Behavior of Tongji-1 Lunar Soil Simulant“. Journal of Aerospace Engineering 32, Nr. 2 (März 2019): 04018150. http://dx.doi.org/10.1061/(asce)as.1943-5525.0000959.

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31

Sharvelle, Sybil, Mazdak Arabi, Eric McLamore und M. Katherine Banks. „Model Development for Biotrickling Filter Treatment of Graywater Simulant and Waste Gas. I“. Journal of Environmental Engineering 134, Nr. 10 (Oktober 2008): 813–25. http://dx.doi.org/10.1061/(asce)0733-9372(2008)134:10(813).

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Schonberg, W. P. „Energy partitioning in high speed impact of analogue solid rocket motors“. Aeronautical Journal 103, Nr. 1029 (November 1999): 519–28. http://dx.doi.org/10.1017/s0001924000064277.

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Abstract Modelling the response of solid rocket motors to bullet and fragment impacts is a high priority among the military services from standpoints of both safety and mission effectiveness. Considerable effort is being devoted to characterising the bullet and fragment vulnerability of solid rocket motors, and to developing solid rocket motor case technologies for preventing or lessening the violent responses of rocket motors to these impact loadings. Because full-scale tests are costly, fast-running analytical methods are required to characterise the response of solid rocket motors to ballistic impact hazards. In this study, a theoretical first-principles-based model is developed to determine the partitioning of the kinetic energy of an impacting projectile among various solid rocket motor failure modes. Failure modes considered in the analyses include case perforation, case delamination, and fragmentation of the propellant simulant material. Energies involved in material fragmentation are calculated using a fragmentation scheme based on a procedure developed in a previous impact study utilising propellant simulant material. The model is found to be capable of predicting a variety of response characteristics for analogue solid rocket motors under high speed projectile impact that are consistent with observed response characteristics. Suggestions are made for improving the model and extending its applicability to a wider class of impact scenarios.

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Li, Peng, Hui Zhang, Shengyuan Jiang und Weiwei Zhang. „Analysis and Testing of Load Characteristics for Rotary-Percussive Drilling of Lunar Rock Simulant with a Lunar Regolith Coring Bit“. Shock and Vibration 2017 (2017): 1–15. http://dx.doi.org/10.1155/2017/3012749.

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Based on an optimized lunar regolith coring bit (LRCB) configuration, the load characteristics of rotary-percussive drilling of lunar rock simulant in a laboratory environment are analyzed to determine the effects of the drilling parameters (the rotational velocity, the penetration rate, and the percussion frequency) on the drilling load. The process of rotary drilling into lunar rock using an LRCB is modeled as an interaction between an elemental blade and the rock. The rock’s fracture mechanism during different stages of the percussive mechanism is analyzed to create a load forecasting model for the cutting and percussive fracturing of rock using an elemental blade. Finally, a model of the load on the LRCB is obtained from the analytic equation for the bit’s cutting blade distribution; experimental verification of the rotary-impact load characteristics for lunar rock simulant with different parameters is performed. The results show that the penetrations per revolution (PPR) are the primary parameter influencing the drilling load. When the PPR are fixed, increasing the percussion frequency reduces the drilling load on the rock. Additionally, the variation pattern of the drilling load of the bit is in agreement with that predicted by the theoretical model. This provides a research basis for subsequent optimization of the drilling procedure and online recognition of the drilling process.

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Park, Chung Hee, Seh Wan Jeong, Hoon Huh und Jung Su Park. „Material Behaviors of PBX Simulant with Various Strain Rates“. Key Engineering Materials 535-536 (Januar 2013): 117–20. http://dx.doi.org/10.4028/www.scientific.net/kem.535-536.117.

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This paper is concerned with the material behaviors of PBX(Polymer Bonded eXplosive) simulant at various strain rates ranging from 0.0001/sec to 3150/sec. Material behaviors of PBX at the high strain rates are important in the prediction of deformation modes of PBX in a warhead which undergoes severe impact loading. Inert PBX stimulant which has analogous material behaviors with PBX was utilized for material tests due to safety issues. Uniaxial compressive tests at quasi-static and intermediate strain rates were conducted with cylindrical specimen using a dynamic materials testing machine, INSTRON 8801. Uniaxial compressive tests at high strain rates ranging from 1200/sec to 3150/sec were conducted using a split Hopkinson pressure bar. Deformation behaviors were investigated using captured images obtained from a high-speed camera. The strain hardening behaviors of PBX simulant were formulated by proposed strain rate-dependent strain hardening model.

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James, Thomas, Samuel Collins, Richard Amlôt und Tim Marczylo. „Analysis of Chemical Simulants in Urine: A Useful Tool for Assessing Emergency Decontamination Efficacy in Human Volunteer Studies“. Prehospital and Disaster Medicine 35, Nr. 5 (30.06.2020): 482–87. http://dx.doi.org/10.1017/s1049023x20000825.

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AbstractIntroduction:To date, all human studies of mass-casualty decontamination for chemical incidents have relied on the collection and analysis of external samples, including skin and hair, to determine decontamination efficacy. The removal of a simulant contaminant from the surface of the body with the assumption that this translates to reduced systemic exposure and reduced risk of secondary contamination has been the main outcome measure of these studies. Some studies have investigated systemic exposure through urinary levels of simulant metabolites. The data obtained in these studies were confounded by high background concentrations from dietary sources. The unmetabolized simulants have never been analyzed in urine for the purposes of decontamination efficacy assessment.Study Objective:Urinary simulant analysis could obviate the need to collect skin or hair samples during decontamination trials and provide a better estimate of both decontamination efficacy and systemic exposure. The study objective therefore was to determine whether gross skin contamination as part of a decontamination study would yield urine levels of simulants sufficient to evaluate systemic availability free from dietary confounders.Methods:In this study, a gas chromatography-tandem mass spectrometry method was developed for the analysis of two chemical simulants, methyl salicylate (MeS) and benzyl salicylate (BeS), in urine. An extraction and sample clean-up method was validated, enabling quantitation of these simulants in urine. The method was then applied to urine collected over a 24-hour period following simulant application to the skin of volunteers.Results:Both MeS and BeS were present in all urine samples and were significantly increased in all post-application samples. The MeS levels peaked one hour after skin application. The remaining urinary levels were variable, possibly due to additional MeS exposures such as inhalation. In contrast, the urinary excretion pattern for BeS was more typical for urinary excretion curves, increasing clearly above baseline from four hours post-dose and peaking between 12.5 and 21 hours, a pattern consistent with dermal absorption and rapid excretion.Conclusion:The authors propose BeS is a useful simulant for use in decontamination studies and that its measurement in urine can be used to model systemic exposures following skin application and therefore likely health consequences.

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Supak, Kevin, Steve Green und Amy McCleney. „Using Tapered Channels to Improve LAD Performance for Cryogenic Fluids: Suborbital Testing Results“. Gravitational and Space Research 9, Nr. 1 (01.01.2021): 115–20. http://dx.doi.org/10.2478/gsr-2021-0009.

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Abstract Improvement of cryogenic fluid storage and transfer technology for in-space propulsion and storage systems is required for long-term space missions. Screened channel liquid acquisition devices (LADs) have long been used with storable propellants to deliver vapor-free liquid during engine restart and liquid transfer processes. The use of LADs with cryogenic fluids is problematic due to low temperatures associated with cryogenic fluids. External heat leaks will cause vapor bubbles to form within the LADs that are difficult to remove in the existing designs. A tapered LAD channel has been proposed to reliably remove vapor bubbles within the device without costly thrusting maneuvers or active separation systems. A model has been developed to predict bubble movement within tapered LAD channels, and subsequent ground testing was completed with a simulant fluid to provide model validation data. Suborbital microgravity testing of tapered LAD technology was recently completed with two different simulant fluids and demonstrated that the concept can passively expel vapor bubbles within the channel. Two additional suborbital flights have been funded to further develop this technology by investigating the performance of larger scale versions of the design.

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Wang, Wen, Kevin Thornton, J. J. Emerson und Manyuan Long. „Nucleotide Variation and Recombination Along the Fourth Chromosome inDrosophila simulans“. Genetics 166, Nr. 4 (01.04.2004): 1783–94. http://dx.doi.org/10.1093/genetics/166.4.1783.

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AbstractThe fourth chromosome of Drosophila melanogaster and its sister species are believed to be nonrecombining and have been a model system for testing predictions of the effects of selection on linked, neutral variation. We recently examined nucleotide variation along the chromosome of D. melanogaster and revealed that a low average level of recombination could be associated with considerably high levels of nucleotide variation. In this report, we further investigate the variation along the fourth chromosome of D. simulans. We sequenced 12 gene regions evenly distributed along the fourth chromosome for a worldwide collection of 11 isofemale lines and 5 gene regions in a local population of 10 isofemale lines from South America. In contrast to predictions for regions of very low recombination, these data reveal that the variation levels in many gene regions, including an intron region of the ci gene, vary considerably along the fourth chromosome. Nucleotide diversity ranged from 0.0010 to 0.0074 in 9 gene regions interspersed with several regions of greatly reduced variation. Tests of recombination indicate that the recombination level is not as low as previously thought, likely an order of magnitude higher than that in D. melanogaster. Finally, estimates of the recombination parameters are shown to support a crossover-plus-conversion model.

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ROUAULT, JACQUES. „THE INFECTION-ENCAPSULATION MODEL — APPLICATION TO DROSOPHILA SIMULANS AND LEPTOPILINA BOULARDI STRAINS FROM TUNISIA“. Journal of Biological Systems 08, Nr. 01 (März 2000): 49–67. http://dx.doi.org/10.1142/s0218339000000055.

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Some larvae of Drosophila infected by parasitic wasps are able to encapsulate the larvae of the parasitoid, and the emerging hosts present a visible melanized capsule in the abdomen. In this paper, a model for estimating the infection rate RI by the rate of hosts presenting a capsule HC is developed. For Drosophila simulans parasitized by Leptopilina boulardi, the model RI = HC/(k+(1-k)HC), with k=0.123, is validated from experimental data. The validation process is based upon a bootstrap strategy over 12870 possibilities of grouping 8 elementary experimental results among 16. Validation consists in fitting the theoretical curve from a data set and in controlling the overlap of the curve with the confidence rectangle established with the complementary data set. This validation process appears to be independent of the confidence level. This infection-encapsulation model is applied to field observations in Tunisia and predicts high levels of infection. This prediction is confirmed at Nasr'Allah by a direct measure of the infection rate. The biological hypotheses involved in this model are discussed. The model merely allows one to follow the evolution of infection in population cages and in the wild, by catching and counting adult hosts, without access to breeding sites. The model is generalisable to other species of hosts and parasitoids presenting the encapsulation reaction.

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Sharvelle, Sybil, Mazdak Arabi, M. Katherine Banks und Fred Mannering. „Model Sensitivity Analysis for Biotrickling Filter Treatment of Graywater Simulant and Waste Gas. II“. Journal of Environmental Engineering 134, Nr. 10 (Oktober 2008): 826–34. http://dx.doi.org/10.1061/(asce)0733-9372(2008)134:10(826).

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Zwirner, J., R. Bayer, A. Japes, F. Eplinius, J. Dreßler und B. Ondruschka. „Suicide by the intraoral blast of firecrackers — experimental simulation using a skull simulant model“. International Journal of Legal Medicine 131, Nr. 6 (30.03.2017): 1581–87. http://dx.doi.org/10.1007/s00414-017-1580-z.

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Sawamura, K., M. T. Yamamoto und T. K. Watanabe. „Hybrid lethal systems in the Drosophila melanogaster species complex. II. The Zygotic hybrid rescue (Zhr) gene of D. melanogaster.“ Genetics 133, Nr. 2 (01.02.1993): 307–13. http://dx.doi.org/10.1093/genetics/133.2.307.

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Abstract Hybrid females from Drosophila simulans females x Drosophila melanogaster males die as embryos while hybrid males from the reciprocal cross die as larvae. We have recovered a mutation in melanogaster that rescues the former hybrid females. It was located on the X chromosome at a position close to the centromere, and it was a zygotically acting gene, in contrast with mhr (maternal hybrid rescue) in simulans that rescues the same hybrids maternally. We named it Zhr (Zygotic hybrid rescue). The gene also rescues hybrid females from embryonic lethals in crosses of Drosophila mauritiana females x D. melanogaster males and of Drosophila sechellia females x D. melanogaster males. Independence of the hybrid embryonic lethality and the hybrid larval lethality suggested in a companion study was confirmed by employing two rescue genes, Zhr and Hmr (Hybrid male rescue), in doubly lethal hybrids. A model is proposed to explain the genetic mechanisms of hybrid lethalities as well as the evolutionary pathways.

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André, S., H. Métivier, G. Lantenois, M. Boyer, D. Nolibé und R. Masse. „Beryllium Metal Solubility in the Lung, Comparison of Metal and Hot-pressed Forms by in vivo and in vitro Dissolution Bioassays“. Human Toxicology 6, Nr. 3 (Mai 1987): 233–40. http://dx.doi.org/10.1177/096032718700600311.

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The solubility of two industrial forms of beryllium, i.e. particles of metal powder and particles of hot-pressed beryllium, was investigated using in vivo and in vitro models. In the in vivo model, baboons and rats were used and were injected via the trachea with amounts of beryllium equivalent to 100, 500 and 1000 fold the maximum permissible concentration (MPC) recommended by the US Occupational Safety and Health Administration. In vivo experiments showed that in both species the daily beryllium solubility rates were about 5 x 10-6 for metal particles and that in rats the daily beryllium solubility rate was about 5 x 10-5 for the hot-pressed particles. During the 10 months of the experiment with baboons, urinary excretion of beryllium was proportional to the amount administered. With regard to results for the in vitro models, the outcome of the acellular dissolution test using a serum simulant was not consistent with the in vivo results, though a cellular model using cultured macrophages showed the same trends in the dissolution rates for the two forms of beryllium as those observed in vivo. This result suggests that a cellular rather than an acellular dissolution model would be better at predicting solubility of beryllium compounds in the lungs.

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Barbash, Daniel A., John Roote und Michael Ashburner. „The Drosophila melanogaster Hybrid male rescue Gene Causes Inviability in Male and Female Species Hybrids“. Genetics 154, Nr. 4 (01.04.2000): 1747–71. http://dx.doi.org/10.1093/genetics/154.4.1747.

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Abstract The Drosophila melanogaster mutation Hmr rescues inviable hybrid sons from the cross of D. melanogaster females to males of its sibling species D. mauritiana, D. simulans, and D. sechellia. We have extended previous observations that hybrid daughters from this cross are poorly viable at high temperatures and have shown that this female lethality is suppressed by Hmr and the rescue mutations In(1)AB and D. simulans Lhr. Deficiencies defined here as Hmr− also suppressed lethality, demonstrating that reducing Hmr+ activity can rescue otherwise inviable hybrids. An Hmr+ duplication had the opposite effect of reducing the viability of female and sibling X-male hybrid progeny. Similar dose-dependent viability effects of Hmr were observed in the reciprocal cross of D. simulans females to D. melanogaster males. Finally, Lhr and Hmr+ were shown to have mutually antagonistic effects on hybrid viability. These data suggest a model where the interaction of sibling species Lhr+ and D. melanogaster Hmr+ causes lethality in both sexes of species hybrids and in both directions of crossing. Our results further suggest that a twofold difference in Hmr+ dosage accounts in part for the differential viability of male and female hybrid progeny, but also that additional, unidentified genes must be invoked to account for the invariant lethality of hybrid sons of D. melanogaster mothers. Implications of our findings for understanding Haldane's rule—the observation that hybrid breakdown is often specific to the heterogametic sex—are also discussed.

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Derome, Nicolas, Emmanuelle Baudry, David Ogereau, Michel Veuille und Catherine Montchamp-Moreau. „Selective Sweeps in a 2-Locus Model for Sex-Ratio Meiotic Drive in Drosophila simulans“. Molecular Biology and Evolution 25, Nr. 2 (10.12.2007): 409–16. http://dx.doi.org/10.1093/molbev/msm269.

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Widén *, H., A. Leufvén und T. Nielsen. „Migration of model contaminants from PET bottles: influence of temperature, food simulant and functional barrier“. Food Additives and Contaminants 21, Nr. 10 (Oktober 2004): 993–1006. http://dx.doi.org/10.1080/02652030400009217.

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Schieber, Garrett L., Brant M. Jones, Thomas M. Orlando und Peter G. Loutzenhiser. „Advection diffusion model for gas transport within a packed bed of JSC-1A regolith simulant“. Acta Astronautica 169 (April 2020): 32–39. http://dx.doi.org/10.1016/j.actaastro.2019.12.031.

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Akashi, H. „Inferring weak selection from patterns of polymorphism and divergence at "silent" sites in Drosophila DNA.“ Genetics 139, Nr. 2 (01.02.1995): 1067–76. http://dx.doi.org/10.1093/genetics/139.2.1067.

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Abstract Patterns of codon usage and "silent" DNA divergence suggest that natural selection discriminates among synonymous codons in Drosophila. "Preferred" codons are consistently found in higher frequencies within their synonymous families in Drosophila melanogaster genes. This suggests a simple model of silent DNA evolution where natural selection favors mutations from unpreferred to preferred codons (preferred changes). Changes in the opposite direction, from preferred to unpreferred synonymous codons (unpreferred changes), are selected against. Here, selection on synonymous DNA mutations is investigated by comparing the evolutionary dynamics of these two categories of silent DNA changes. Sequences from outgroups are used to determine the direction of synonymous DNA changes within and between D. melanogaster and Drosophila simulans for five genes. Population genetics theory shows that differences in the fitness effect of mutations can be inferred from the comparison of ratios of polymorphism to divergence. Unpreferred changes show a significantly higher ratio of polymorphism to divergence than preferred changes in the D. simulans lineage, confirming the action of selection at silent sites. An excess of unpreferred fixations in 28 genes suggests a relaxation of selection on synonymous mutations in D. melanogaster. Estimates of selection coefficients for synonymous mutations (3.6 < magnitude of Nes < 1.3) in D. simulans are consistent with the reduced efficacy of natural selection (magnitude of Nes < 1) in the three- to sixfold smaller effective population size of D. melanogaster. Synonymous DNA changes appear to be a prevalent class of weakly selected mutations in Drosophila.

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Harris, Harriet L., und Henk R. Braig. „Sperm chromatin remodelling and Wolbachia-induced cytoplasmic incompatibility in Drosophila“. Biochemistry and Cell Biology 81, Nr. 3 (01.06.2003): 229–40. http://dx.doi.org/10.1139/o03-053.

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Wolbachia pipientis is an obligate bacterial endosymbiont, which has successfully invaded approximately 20% of all insect species by manipulating their normal developmental patterns. Wolbachia-induced phenotypes include parthenogenesis, male killing, and, most notably, cytoplasmic incompatibility. In the future these phenotypes might be useful in controlling or modifying insect populations but this will depend on our understanding of the basic molecular processes underlying insect fertilization and development. Wolbachia-infected Drosophila simulans express high levels of cytoplasmic incompatibility in which the sperm nucleus is modified and does not form a normal male pronucleus when fertilizing eggs from uninfected females. The sperm modification is somehow rescued in eggs infected with the same strain of Wolbachia. Thus, D. simulans has become an excellent model organism for investigating the manner in which endosymbionts can alter reproductive programs in insect hosts. This paper reviews the current knowledge of Drosophila early development and particularly sperm function. Developmental mutations in Drosophila that are known to affect sperm function will also be discussed.Key words: sperm chromatin, fertilization, Drosophila, Wolbachia, cytoplasmic incompatibility.

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Pastina, Barbara, und Jay A. LaVerne. „An Alternative Conceptual Model for the Spent Nuclear Fuel–Water Interaction in Deep Geologic Disposal Conditions“. Applied Sciences 11, Nr. 18 (15.09.2021): 8566. http://dx.doi.org/10.3390/app11188566.

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For the long-term safety assessment of direct disposal of spent nuclear fuel in deep geologic repositories, knowledge on the radionuclide release rate from the UO2 matrix is essential. This work provides a conceptual model to explain the results of leaching experiments involving used nuclear fuel or simulant materials in confirmed reducing conditions. Key elements of this model are: direct effect of radiation from radiolytic species (including defects and excited states) in the solid and in the first water layers in contact with its surface; and excess H2 may be produced due to processes occurring at the surface of the spent fuel and in confined water volumes, which may also play a role in keeping the spent fuel surface in a reduced state. The implication is that the fractional radionuclide release rate used in most long-term safety assessments (10−7 year−1) is over estimated because it assumes that there is net UO2 oxidation caused by radiolysis, in contrast with the alternative conceptual model presented here. Furthermore, conventional water radiolysis models and radiation chemical yields published in the literature are not directly applicable to a heterogeneous system such as the spent fuel–water interface. Suggestions are provided for future work to develop more reliable models for the long-term safety assessment of spent nuclear fuel disposal.

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FRYE, MARSHALL, SHANGRADHANVA E. VASISTH, AMALIE ATASSI, DAVID MAZYCK und JUAN C. NINO. „EFFECT OF DEGREE OF SULFONATION IN NANOCELLULOSE/CHITOSAN COMPOSITE ON ADSORPTION OF CATIONIC DYE AS OPIOID SIMULANT“. Cellulose Chemistry and Technology 55, Nr. 1-2 (12.02.2021): 87–99. http://dx.doi.org/10.35812/cellulosechemtechnol.2021.55.09.

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In this study, the effect of nanocellulose sulfonate group content on adsorption of an opioid simulant was tested. The opioid simulant used was Victoria blue R, an amine dye. Nanocellulose filters were fabricated by crosslinking cellulose nanocrystals (CNCs) with chitosan to improve the mechanical stability of freeze-dried CNCs. Thermogravimetric analysis confirmed the filter’s thermal stability and operating temperatures. Conductometric titration, Fourier transform infrared spectroscopy, and scanning electron microscopy techniques were used to characterize the degree of nanocellulose functionalization. Lastly, the adsorption performance of the sulfonated nanocellulose filter was tested and fitted to kinetic models and adsorption isotherms. The adsorption of the dye by the sulfonated nanocellulose followed pseudo-second order kinetics and the Langmuir isotherm. The maximum adsorption of Victoria blue R dye by sulfonated nanocellulose (68.56 mg/g) is significantly higher than those of other adsorbents, like activated carbon (0.59-2.97 mg/g) and magnetic microparticles (40.98 mg/g). Thus, sulfonated cellulose nanocrystals are a promising material for the sequestration of opioids from water.

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