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71.
In this study, the Spectral Relaxation Method (SRM) is used to solve the coupled highly nonlinear system of partial differential equations due to an unsteady flow over a stretching surface in an incompressible rotating viscous fluid in presence of binary chemical reaction and Arrhenius activation energy. The velocity, temperature and concentration distributions as well as the skin-friction, heat and mass transfer coefficients have been obtained and discussed for various physical parametric values. The numerical results obtained by (SRM) are then presented graphically and discussed to highlight the physical implications of the simulations. 相似文献
72.
73.
R. B. Taylor M. I. Awad R. G. Reid R. R. Moody 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2000,744(2):277
A chromatographic method is described for the determination of sodium artesunate in plasma. This includes cetyltrimethylammonium bromide as a cationic pairing ion in a reversed-phase system using an octadecylsilica 100×4.6 mm I.D. 3 μm analytical column with a mobile phase of acetonitrile/acetate buffer at pH7. Column switching incorporating a 5 μm octadecylsilica 100×4.6 mm I.D. precolumn is used in addition to off-line solid-phase extraction for pretreatment of plasma samples in order to eliminate interference from endogenous components. Detection is by post-column derivatisation with 1.0 M methanolic KOH followed by UV detection at 289 nm. Calibration is linear over the range 100–1600 ng ml−1 and the limit of detection is estimated as 20 ng ml−1. Illustrative results are shown of the artesunate plasma levels determined by the proposed method following the administration of artesunate as tablets and as suppositories to healthy volunteers. 相似文献
74.
Kevin Korfmann Diala Abu Awad Aurélien Tellier 《Journal of evolutionary biology》2023,36(9):1282-1294
Seed banking (or dormancy) is a widespread bet-hedging strategy, generating a form of population overlap, which decreases the magnitude of genetic drift. The methodological complexity of integrating this trait implies it is ignored when developing tools to detect selective sweeps. But, as dormancy lengthens the ancestral recombination graph (ARG), increasing times to fixation, it can change the genomic signatures of selection. To detect genes under positive selection in seed banking species it is important to (1) determine whether the efficacy of selection is affected, and (2) predict the patterns of nucleotide diversity at and around positively selected alleles. We present the first tree sequence-based simulation program integrating a weak seed bank to examine the dynamics and genomic footprints of beneficial alleles in a finite population. We find that seed banking does not affect the probability of fixation and confirm expectations of increased times to fixation. We also confirm earlier findings that, for strong selection, the times to fixation are not scaled by the inbreeding effective population size in the presence of seed banks, but are shorter than would be expected. As seed banking increases the effective recombination rate, footprints of sweeps appear narrower around the selected sites and due to the scaling of the ARG are detectable for longer periods of time. The developed simulation tool can be used to predict the footprints of selection and draw statistical inference of past evolutionary events in plants, invertebrates, or fungi with seed banks. 相似文献
75.
Mohamed Sabry Abd Elraheam Elsayed Awad A. Shehata Ahmed Mohamed Ammar Tamer S. Allam Abdallah S. Ali Rasha H. Ahmed A.B. Abeer Mohammed Reda Tarabees 《Saudi Journal of Biological Sciences》2021,28(5):2850-2857
The effects of a multistrain potential probiotic (Protexin®), acids, and a bacterin from multidrug-resistant E. coli O26, O78, S. Enteritidis (1,9,12 g.m1,7), and S. Typhimurium (1,4,5,12.i.1,2) on the immune response, haematological parameters, cytokines, and growth parameters of broiler chickens challenged with bacterin live serotypes were investigated. Two experiments were designed using 300 one-day-old chicks (Arbor Acres) randomly assigned to 15 groups. The first experiment comprised 9 groups, including positive and negative control groups and other groups received Protexin®, acids, and the bacterin (0.2 ml/SC), either alone or in combination, on the 1st day. The second experiment contained 6 groups, including positive and negative control groups and other groups received a combination of Protexin®, acids, and the bacterin (0.5 ml/SC) on the 8th day. All the groups except the negative control groups were challenged on the 8th and 16th days in both experiments, respectively, with mixed live bacterin serotypes. The groups that received Protexin®, acids, and the bacterin either alone or in combination revealed significant improvements in the immune response to the bacterin (p ≤ 0.05). The groups in the 1st experiment and most the 2nd experiment groups showed a reduced mortality rate and decreased levels IFN-γ, IL-4, and IL-12 cytokines (p ≤ 0.05). Moreover, these groups demonstrated increases in haematological parameters and reduced rates of infection-caused anaemia. These groups showed significant increases in growth performance parameters, such as body weight, weight gain, and the feed conversion ratio (FCR) (p ≤ 0.05). There was a beneficial effect on 1-day-old chickens produced by combining Protexin®, acids, and the bacterin (0.2 ml/SC). 相似文献
76.
Jameela?M.A. Shinwari Arif Khan Salma Awad Zakia Shinwari Ayodele Alaiya Mohamad Alanazi Asma Tahir Coralie Poizat Nada Al?Tassan 《American journal of human genetics》2015,96(1):147-152
Abnormal ocular motility is a common clinical feature in congenital cranial dysinnervation disorder (CCDD). To date, eight genes related to neuronal development have been associated with different CCDD phenotypes. By using linkage analysis, candidate gene screening, and exome sequencing, we identified three mutations in collagen, type XXV, alpha 1 (COL25A1) in individuals with autosomal-recessive inheritance of CCDD ophthalmic phenotypes. These mutations affected either stability or levels of the protein. We further detected altered levels of sAPP (neuronal protein involved in axon guidance and synaptogenesis) and TUBB3 (encoded by TUBB3, which is mutated in CFEOM3) as a result of null mutations in COL25A1. Our data suggest that lack of COL25A1 might interfere with molecular pathways involved in oculomotor neuron development, leading to CCDD phenotypes. 相似文献
77.
Scanning and transmission electron microscopy of the female reproductive system of Schistosoma margrebowiei Le Roux, 1933 总被引:1,自引:0,他引:1
Transmission electron microscopy shows that the uterus of female Schistosoma margrebowiei possesses the same ultrastructure as that of the tegument but lacks spines and sense organs. It does not possess secretory cells and opens at the gonopore which by scanning electron microscopy was seen to be composed of numerous leaf-like protrusions. The morphology of the ovary is comparable with that of other Digenea. Immature and mature ova possess cortically arranged granules and occur within the posterior zone of the ovary. Cilia and lamellae line the luminal surface of the oviduct and ootype, the lamellae running unidirectionally along the duct. Only a single type of secretory cell is seen within Mehlis' gland and this produces dense bodies which are associated with Goldi bodies. Narrow cytoplasmic channels supported by microtubules deliver these secretory bodies to the ootype. The vitelline duct is lined with cilia and lamellae and the vitelline gland contains four types of cells, S1, S2, S3 and S4. Calcareous corpuscles are found within mature S4 cells. 相似文献
78.
Temperature markedly affected germination and germ tube length of A. niger. More than 90% of the spores were germinated in the range 30°–34 °C and formed maximum length of germ tubes. At temperatures from 38° to 43 °C, the proportion of the spores that germinated as well as the germ tube length were both gradually decreased. However, at 47°C germ tube formation was completely inhibited up to 15 hrs. after inoculation.High relative humidity was found necessary for the spore germination of A. niger. Germination failed to occur at 76% relative humidity. At 78 and 81% relative humidity germination was detected 15 hrs. after inoculation while at the higher humidities germination was started after 6 hrs. only.Conidiospores of A. niger were very sensitive to changes in the hydrogen ion concentration, pH. Complete inhibition of germination was found at pH less than 3.5. The germination and the length of the formed germ tubes increased with pH to reach their maximum rates at pH 4.5. 相似文献
79.
Utility of Von Pechman synthesis of coumarin reaction for development of spectrofluorimetric method for quantitation of salmeterol xinafoate in pharmaceutical preparations and human plasma 下载免费PDF全文
Mohamed Awad Mohamed A. Hammad Ahmed M. Abdel‐Megied Mahmoud A. Omar 《Luminescence》2018,33(5):913-918
Simple, precise and selective spectrofluorimetric technique was evolved for quantitation of selective β2 agonist drug namely salmeterol xinafoate (SAL). Utilizing its phenolic nature, a method was described based on the reaction of the studied drug with ethyl acetoacetate (EAA) to yield extremely fluorescent coumarin product which can be detected at 480 nm (λex = 420 nm). The procedure obeys Beer's law with a correlation coefficient of r = 0.9999 in the concentration range between 500 and 5000 ng ml?1 with and 177 ng ml?1 for limit of detection (LOD) and limit of quantification (LOQ), respectively. Diverse reaction variables influencing the firmness and formation of the coumarin product were accurately examined and modified to ensure greatest sensitivity of the procedure. The proposed technique was performed and examined according to the US Food and Drug Administration (FDA) guidelines for bio‐analytical methods and was efficiently applied for quantitation of SAL in both pharmaceutical preparations (% recovery = 100.06 ± 1.07) and spiked human plasma (% recovery = 96.64–97.14 ± 1.01–1.52). 相似文献
80.
Yasir Serag Alnor Gorafi June-Sik Kim Awad Ahmed Elawad Elbashir Hisashi Tsujimoto 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(8):1615-1626