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471.
Saima Noreen 《PloS one》2013,8(11)
This research is concerned with the peristaltic flow of third order nanofluid in an asymmetric channel. The governing equations of third order nanofluid are modelled in wave frame of reference. Effect of induced magnetic field is considered. Long wavelength and low Reynolds number situation is tackled. Numerical solutions of the governing problem are computed and analyzed. The effects of Brownian motion and thermophoretic diffusion of nano particles are particularly emphasized. Physical quantities such as velocity, pressure rise, temperature, induced magnetic field and concentration distributions are discussed. 相似文献
472.
This study tested preference for abstract patterns, comparing random patterns to a two-fold bilateral symmetry. Stimuli were presented at random locations in the periphery. Preference for bilateral symmetry has been extensively studied in central vision, but evaluation at different locations had not been systematically investigated. Patterns were presented for 200 ms within a large circular region. On each trial participant changed fixation and were instructed to select any location. Eccentricity values were calculated a posteriori as the distance between ocular coordinates at pattern onset and coordinates for the centre of the pattern. Experiment 1 consisted of two Tasks. In Task 1, participants detected pattern regularity as fast as possible. In Task 2 they evaluated their liking for the pattern on a Likert-scale. Results from Task 1 revealed that with our parameters eccentricity did not affect symmetry detection. However, in Task 2, eccentricity predicted more negative evaluation of symmetry, but not random patterns. In Experiment 2 participants were either presented with symmetry or random patterns. Regularity was task-irrelevant in this task. Participants discriminated the proportion of black/white dots within the pattern and then evaluated their liking for the pattern. Even when only one type of regularity was presented and regularity was task-irrelevant, preference evaluation for symmetry decreased with increasing eccentricity, whereas eccentricity did not affect the evaluation of random patterns. We conclude that symmetry appreciation is higher for foveal presentation in a way not fully accounted for by sensitivity. 相似文献
473.
Diverse associations among coral host haplotypes and algal endosymbionts may drive adaptation at geographically peripheral and ecologically marginal locations
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475.
Rachid Bouagina Johnny Padulo Akram Fray Alin Larion Hatem Abidi Mokhtar Chtara Mohamed Souhail Chelly Riadh Khalifa 《Biology of sport / Institute of Sport》2022,39(2):415
This study investigated the effects of a ballistic training programme using an arm/shoulder specific strength device (ASSSD) on the upper body peak power (PP), muscle volume (MV) of the dominant arm and throwing velocity in junior handball players. Twenty-six players were randomly assigned to an experimental (EG = 15, age 17.6 ± 0.51 years) and control (CG = 11, age 17.36 ± 0.50 years) group. Over an 8-week in-season period, the EG performed a ballistic training programme (2 sessions/week) immediately before their normal team handball training. Both groups underwent tests on the ASSSD, which operates in consecutive accelerative and decelerative actions, for throwing characteristics determination. Peak power (PP), peak force (PF), peak velocity (PV), peak rate of power development (PRPD), muscle volume (MV), throwing velocity with runup, standing throw, and jump throw were also assessed before/after the training programme. The EG group showed significant post-training improvements in PP (52.50% – p < 0.001), PF (26.45% – p < 0.01) and PRPD (78.47% – p < 0.001) better than the CG (1.81, 0.67 and 1.64%, p > 0.05, respectively). There was also a post-training improvement in the velocity at PP (22.82% – p < 0.001) and PF (42.45% – p < 0.001) in the EG compared to the CG (4.18 and 8.53%, p > 0.05 respectively). There was a significant increase in acceleration at PP (51.50% – p < 0.01) and PF (69.67% – p < 0.001). MV increased (19.11% – p < 0.001) in the EG, with no significant change (3.34% – p = 0.84) in the CG. Finally, significant increases were obtained in the three throw types (3.1–6.21%, p < 0.05- < 0.001) in the EG compared to the CG. The additional ASSSD training protocol was able to improve muscle strength/volume and ball throwing velocity in junior handball players. 相似文献
476.
Schistosomes are long lived, intravascular parasitic platyhelminths that infect >200 million people globally. The molecular mechanisms used by these blood flukes to dampen host immune responses are described in this review. Adult worms express a collection of host-interactive tegumental ectoenzymes that can cleave host signaling molecules such as the “alarmin” ATP (cleaved by SmATPDase1), the platelet activator ADP (SmATPDase1, SmNPP5), and can convert AMP into the anti-inflammatory mediator adenosine (SmAP). SmAP can additionally cleave the lipid immunomodulator sphingosine-1-phosphate and the proinflammatory anionic polymer, polyP. In addition, the worms release a barrage of proteins (e.g., SmCB1, SjHSP70, cyclophilin A) that can impinge on immune cell function. Parasite eggs also release their own immunoregulatory proteins (e.g., IPSE/α1, omega1, SmCKBP) as do invasive cercariae (e.g., Sm16, Sj16). Some schistosome glycans (e.g., LNFPIII, LNnT) and lipids (e.g., Lyso-PS, LPC), produced by several life stages, likewise affect immune cell responses. The parasites not only produce eicosanoids (e.g., PGE2, PGD2—that can be anti-inflammatory) but can also induce host cells to release these metabolites. Finally, the worms release extracellular vesicles (EVs) containing microRNAs, and these too have been shown to skew host cell metabolism. Thus, schistosomes employ an array of biomolecules—protein, lipid, glycan, nucleic acid, and more, to bend host biochemistry to their liking. Many of the listed molecules have been individually shown capable of inducing aspects of the polarized Th2 response seen following infection (with the generation of regulatory T cells (Tregs), regulatory B cells (Bregs) and anti-inflammatory, alternatively activated (M2) macrophages). Precisely how host cells integrate the impact of these myriad parasite products following natural infection is not known. Several of the schistosome immunomodulators described here are in development as novel therapeutics against autoimmune, inflammatory, and other, nonparasitic, diseases. 相似文献
477.
Mohammed Kuddus Fahmida Khatoon Mohd Saleem Sadaf Anwar Syed Monowar Alam Shahid Tarig Ginawi Ashfaque Hossain Akram Abdullah Malaqi Alnabri Ziyad Fayez Alshammari Abdulaziz Mohammed Alrabie Sami Shayih Jehad Alenazi Motaz Monif F Alshammari Mohd Adnan Kausar 《Bioinformation》2021,17(5):541
Biocontaminants are minute particles derived from different biological materials. Indoor biocontaminants are associated with major public health problems. In Gulf countries, it is more precarious due to the harsh climatic conditions, including high ambient temperatures and relative humidity. In addition, due to COVID-19 pandemic, most of the time public is inside their home. Therefore, the aim of the study was to determine the load of biocontaminants in the indoor environment of Hail city. The results showed that most of the bacteria are gram-positive and higher in polymicrobial (87.1%) than monomicrobial (62.7%) association. There was no significant association with sample collection time and types of isolates. The most abundant microbes found in all samples were Staphylococcus aureus followed by Bacillus spp. Among Gram-negative bacterial isolates, E. coli was most common in tested indoor air samples. The study will be useful to find the biocontaminants associated with risk factors and their impact on human health in indoor environment, especially during the COVID-19 pandemic. These results indicate the need to implement health care awareness programs in the region to improve indoor air quality. 相似文献
478.
Joseph Pitula William T Ruyechan Noreen Williams 《Biochemical and biophysical research communications》2002,290(1):569-576
We have previously reported the identification of two closely related RNA binding proteins from Trypanosoma brucei which we have termed p34 and p37. The predicted primary structures of the two proteins are highly homologous with one major difference, an 18-amino-acid insert in the N-terminal region of p37. These two proteins have been localized to the nucleus based on immunofluorescence microscopy. To gain insight into their function, we have utilized UV crosslinking, coimmunoprecipitation, and sucrose density gradients to identify T. brucei RNA species that associate with p34 and p37. These experiments have demonstrated a specific interaction of both p34 and p37 with the 5S ribosomal RNA and indicate that other RNA species are unlikely to be specifically bound. This suggests a role for p34 and p37 in the import and/or assembly pathway of T. brucei 5S rRNA in ribosome biogenesis. 相似文献
479.
480.
Abdolhossein Rustaiyan Akram Niknejad Lilly Nazarians Jasmin Jakupovic Ferdinand Bohlmann 《Phytochemistry》1982,21(7):1812-1813
The aerial parts of Salvia hypoleuca afforded two sesterterpenes with a previously unknown carbon skeleton. 相似文献