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101.
102.
Fujarewicz K Kimmel M Lipniacki T Swierniak A 《IEEE/ACM transactions on computational biology and bioinformatics / IEEE, ACM》2007,4(3):322-335
The paper concerns the problem of fitting mathematical models of cell signaling pathways. Such models frequently take the form of sets of nonlinear ordinary differential equations. While the model is continuous in time, the performance index used in the fitting procedure involves measurements taken at discrete time moments. Adjoint sensitivity analysis is a tool which can be used for finding the gradient of a performance index in the space of parameters of the model. In the paper, a structural formulation of adjoint sensitivity analysis called the generalized backpropagation through time (GBPTT) is used. The method is especially suited for hybrid, continuous-discrete time systems. As an example, we use the mathematical model NF-kappaB of the regulatory module, which plays a major role in the innate immune response in animals. 相似文献
103.
Karhánek D Kacer P Kuzma M Splíchalová J Cervený L 《Journal of molecular modeling》2007,13(9):1009-1016
Theoretical investigation of Pt(0)-olefin organometallic complexes containing tertiary phosphine ligands was focused on the
strength of platinum-olefin electronic interaction. DFT theoretical study of electronic effects in a substantial number of
ethylene derivatives was evaluated in terms of the Pt-olefin binding energy using MP2 correlation theory. Organometallics
bearing coordinated olefins with general formula (R1R2C = CR3R4)Pt(PH3)2 [R = various substituents] had been selected, including olefins containing both electron-donor substituents as well as electron-withdrawing
groups. The stability of the corresponding complexes increases with a strengthening electron-withdrawal ability of the olefin
substituents.
Figure Representation of (CH2 = CHR)Pt(PPh3)2 and the stability chart 相似文献
104.
We analysed 16 populations of Dactylorhiza majalis subsp. majalis from northern Poland, simultaneously utilizing both morphological and molecular data. Genetic differentiation was examined using five microsatellite loci, and morphological variation was assessed for 23 characters. At the species level, our results showed a moderate level of genetic diversity (A = 6.00; Ae = 1.86; Ho = 0.387; FIS = 0.139) which varied between the studied populations (A = 2.60–4.20; Ae = 1.68–2.39; Ho = 0.270–0.523; FIS = ?0.064–0.355). A significant excess of homozygotes was detected in five population, while excess of heterozygotes was observed in four populations, but the latter values were statistically insignificant. Moderate, but clear between population genetic differentiation was found (FST = 0.101; p < 0.001). Considering pairwise‐FST and number of migrants among populations, we recognized three population groups (I, II, III), where the first could be further divided into two subgroups (Ia, Ib). These three groups differed with respect to gene flow values (Nm = 0.39–1.12). The highest number of migrants per generation was noticed among populations of subgroup Ia (8.58), indicative of a central panmictic population with free gene flow surrounded by peripatric local populations (Ib) with more limited gene flow. Geographic isolation, habitat fragmentation and limited seed dispersal are inferred to have caused limitations to gene flow among the three indicated population groups. There was a significant correlation between the morphological and genetic distance matrices. A weak but significant pattern of isolation by distance was also observed (r = 0.351; p < 0.05). 相似文献
105.
Kieliszek Marek Błażejak Stanisław Bzducha-Wróbel Anna Kot Anna M. 《Biological trace element research》2019,187(1):328-328
Biological Trace Element Research - The authors forgot to include the following information in Materials and Methods. 相似文献
106.
Marzec-Wróblewska Urszula Kamiński Piotr Łakota Paweł Szymański Marek Wasilow Karolina Ludwikowski Grzegorz Jerzak Leszek Stuczyński Tomasz Woźniak Alina Buciński Adam 《Biological trace element research》2019,188(2):251-260
Biological Trace Element Research - We analyzed cobalt (Co), chromium (Cr), and lead (Pb) concentrations in human semen and catalase CAT activity in seminal plasma and the effects of their... 相似文献
107.
Litvín Radek Bína David Herbstová Miroslava Pazderník Marek Kotabová Eva Gardian Zdenko Trtílek Martin Prášil Ondřej Vácha František 《Photosynthesis research》2019,142(2):137-151
Photosynthesis Research - Survival of phototrophic organisms depends on their ability to collect and convert enough light energy to support their metabolism. Phototrophs can extend their absorption... 相似文献
108.
Zivcak Marek Brestic Marian Botyanszka Lenka Chen Yang-Er Allakhverdiev Suleyman I. 《Photosynthesis research》2019,139(1-3):239-251
Photosynthesis Research - In our experiments, we examined high light responses and photosynthetic capacity of chlorophyll-less isogenic mutant lines of hexaploid bread wheat (Triticum aestivum L.)... 相似文献
109.
Shoji Kuretake Marek Maleszewski Ako Tokumasu Hirokazu Fujimoto Ryuzo Yanagimachi 《Molecular reproduction and development》1996,44(2):230-233
Mice carrying two t complementary haplotypes (tw5/tw32) are totally sterile. Their spermatozoa have poor motility and fertilize neither zone-intact nor zona-free oocytes, even though they are structurally indistinguishable from control (wild-type) spermatozoa. However, when injected directly into oocytes, these infertile spermatozoa are able to participate in normal development. This suggests that infertility of tw5/tw32 male (spermatozoa) is more likely to be due to poor sperm-oocyte interaction than to genetic incompetence of sperm nuclei. © 1996 Wiley-Liss, Inc. 相似文献
110.