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71.
`The aim of this analysis is to investigate the existence of the dual solutions for magnetohydrodynamic (MHD) flow of an upper-convected Maxwell (UCM) fluid over a porous shrinking wall. We have employed the Lie group analysis for the simplification of the nonlinear differential system and computed the absolute invariants explicitly. An efficient numerical technique namely the shooting method has been employed for the constructions of solutions. Dual solutions are computed for velocity profile of an upper-convected Maxwell (UCM) fluid flow. Plots reflecting the impact of dual solutions for the variations of Deborah number, Hartman number, wall mass transfer are presented and analyzed. Streamlines are also plotted for the wall mass transfer effects when suction and blowing situations are considered. 相似文献
72.
Shahida Shaheen Rafiq Ahmad Hussani Mubarak Nosheen Mirza Malik Tahir Hayat 《International journal of phytoremediation》2018,20(11):1162-1167
The effects of cadmium stress (0, 25, 50, 75, and 100 mg/L) on morpho-physiological features and selected genes (carotenoid hydroxilase, amidase, GR, bHLH, NRAMP and YSL) expression were demonstrated in Arundo donax L. The plants were assessed for Cd uptake and its effects on chlorophyll and antioxidants after 30 days of exposure. The expression of genes conferring metal tolerance was evaluated after 10 days of Cd exposure. The results showed a maximum Cd uptake in roots (872 mg/kg) followed by stem (734 mg/kg) and leaves (298 mg/kg) at highest supplied Cd concentration. The Cd uptake reduced dry weight, Chla, Chlb, and total Chl contents of giant reed. The SOD, CAT, POD activities and MDA content increased at the maximum Cd concentration over control. The highest genes expression for carotenoid hydroxylase, glutathione reductase and amidase was observed in plants exposed to 100 mg/L. However, differential bHLH gene expression and slightly increased gene expression of NRAMP was noted for different Cd treatments. Amidase expressed under Cd stress which is pioneer report in A. donax. These results provided insights into the mechanisms of A. donax tolerance and survival under Cd Stress. 相似文献
73.
Application of induced pluripotent stem cell and embryonic stem cell technology to the study of male infertility
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Javad Amini Mahabadi Hamed Sabzalipour Hassan Hassani Bafrani Seyed Mohammad Gheibi Hayat Hossein Nikzad 《Journal of cellular physiology》2018,233(11):8441-8449
Stem cells (SCs) are classes of undifferentiated biological cells existing only at the embryonic, fetal, and adult stages that can divide to produce specialized cell types during fetal development and remain in our bodies throughout life. The progression of regenerative and reproductive medicine owes the advancement of respective in vitro and in vivo biological science on the stem cell nature under appropriate conditions. The SCs are promising therapeutic tools to treat currently of infertility because of wide sources and high potency to differentiate. Nevertheless, no effective remedies are available to deal with severe infertility due to congenital or gonadotoxic stem cell deficiency in prepubertal childhood. Some recent solutions have been developed to address the severe fertility problems, including in vitro formation of germ cells from stem cells, induction of pluripotency from somatic cells, and production of patient‐specific pluripotent stem cells. There is a possibility of fertility restoration using the in vitro formation of germ cells from somatic cells. Accordingly, the present review aimed at studying the literature published on the medical application of stem cells in reproductive concerns. 相似文献
74.
Syed Lal Badshah Junlei Sun Sam Mula Mike Gorka Patricia Baker Rajiv Luthra Su Lin Art van der Est John H. Golbeck Kevin E. Redding 《BBA》2018,1859(1):42-55
In Photosystem I, light-induced electron transfer can occur in either of two symmetry-related branches of cofactors, each of which is composed of a pair of chlorophylls (ec2A/ec3A or ec2B/ec3B) and a phylloquinone (PhQA or PhQB). The axial ligand to the central Mg2 + of the ec2A and ec2B chlorophylls is a water molecule that is also H-bonded to a nearby Asn residue. Here, we investigate the importance of this interaction for charge separation by converting each of the Asn residues to a Leu in the green alga, Chlamydomonas reinhardtii, and the cyanobacterium, Synechocystis sp. PCC6803, and studying the energy and electron transfer using time-resolved optical and EPR spectroscopy. Nanosecond transient absorbance measurements of the PhQ to FX electron transfer show that in both species, the PsaA-N604L mutation (near ec2B) results in a ~ 50% reduction in the amount of electron transfer in the B-branch, while the PsaB-N591L mutation (near ec2A) results in a ~ 70% reduction in the amount of electron transfer in the A-branch. A diminished quantum yield of P700+ PhQ? is also observed in ultrafast optical experiments, but the lower yield does not appear to be a consequence of charge recombination in the nanosecond or microsecond timescales. The most significant finding is that the yield of electron transfer in the unaffected branch did not increase to compensate for the lower yield in the affected branch. Hence, each branch of the reaction center appears to operate independently of the other in carrying out light-induced charge separation. 相似文献
75.
In vitro antibiofilm and anti‐adhesion effects of magnesium oxide nanoparticles against antibiotic resistant bacteria
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Sumreen Hayat Saima Muzammil Muhammad Hidayat Rasool Zonaira Nisar Syed Zajif Hussain Anjum Nasim Sabri Saba Jamil 《Microbiology and immunology》2018,62(4):211-220
76.
Zorica Nedeljković Ante Vujić Rüstem Hayat Ljiljana Šašić Zorić Mihajla Đan 《Zoology in the Middle East.》2018,64(3):244-252
A new species of the genus Chrysotoxum (Diptera: Syrphidae), Chrysotoxum bozdagensis Nedeljkovi?, Vuji? &; Hayat sp. n., collected from Bozda? Mt., ?zmir Province, Turkey is described and illustrated. Chrysotoxum bozdagensis sp. n. can be distinguished from the similar Ch. octomaculatum Curtis, 1837 by the presence of a black pile on the mesonotum and the colour of the legs. It is also similar to Ch. elegans Loew, 1841, from which it can be distinguished by the colour of the pile on the vertical triangle and scutellum, as well from the structure of the male genitalia. Additionally, Ch. bozdagensis sp. n. can be clearly distinguished from the latter two species by DNA sequence data. This new species increases the total number of Chrysotoxum species in Turkey to 18.http://www.zoobank.org/urn:lsid:zoobank.org:pub:7465AAEA-21E6-4F0F-984C-CD48BE75436F 相似文献
77.
Faiza Gulzar Qaisar Mahmood Zulfiqar Ahmad Bhatti Bibi Saima Zeb Shahida Shaheen Tahir Hayat Naeem Shahid Tahseen Zeb 《World journal of microbiology & biotechnology》2018,34(8):119
Wastewater treatment based on ecological principles is a low cost and highly desirable solution for the developing countries like Pakistan. The present study evaluated the effectiveness of biological treatment systems including Internal Circulation (IC) anaerobic bioreactor and constructed wetlands (CWs) containing macrophytes and mixed algal cultures for industrial wastewater treatment. The IC bioreactor reduced COD (52%), turbidity (89%), EC (24%) of the industrial wastewater. However, the effluents of IC bioreactor did not comply with National Environmental Quality Standards (NEQS) of Pakistan. Post-treatment of IC bioreactor effluents was accomplished in CW containing macrophytes (Arundo donax and Eichhornia crassipes) and mixed algal culture. The CWs planted with macrophytes lowered the concentrations of COD (89%) and turbidity (99%). CWs with algal biomass were not effective in further polishing the effluent. Inhibition of algal biomass growth was observed due to physicochemical characteristics of wastewater. The integrated treatment system consisting of IC bioreactor and macrophytes was found more suitable option for industrial wastewater treatment. 相似文献
78.
The leader polypeptide of Theiler's virus is essential for neurovirulence but not for virus growth in BHK cells. 总被引:4,自引:3,他引:1
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M A Calenoff C S Badshah M C Dal Canto H L Lipton M K Rundell 《Journal of virology》1995,69(9):5544-5549
A leader polypeptide of unknown function is encoded by cardioviruses, such as Theiler's murine encephalomyelitis virus. Although the deletion of this polypeptide has little effect on the growth of parental GDVII virus in baby hamster kidney (BHK) cells, the mutant virus is completely attenuated and fails to kill mice receiving intracerebral inoculations of high doses of the virus. 相似文献
79.
To better understand the interaction of physical activity and air pollution exposure, it is important to quantify the change in ventilation rate incurred by activity. In this paper, we describe a method for estimating ventilation using easily-measured variables such as heart rate (HR), breathing rate (fB), and forced vital capacity (FVC). We recruited healthy adolescents to use a treadmill while we continuously measured HR, fB, and the tidal volume (VT) of each breath. Participants began at rest then walked and ran at increasing speed until HR was 160–180 beats per minute followed by a cool down period. The novel feature of this method is that minute ventilation () was normalized by FVC. We used general linear mixed models with a random effect for subject and identified nine potential predictor variables that influence either or FVC. We assessed predictive performance with a five-fold cross-validation procedure. We used a brute force selection process to identify the best performing models based on cross-validation percent error, the Akaike Information Criterion and the p-value of parameter estimates. We found a two-predictor model including HR and fB to have the best predictive performance (/FVC = -4.247+0.0595HR+0.226fB, mean percent error = 8.1±29%); however, given the ubiquity of HR measurements, a one-predictor model including HR may also be useful (/FVC = -3.859+0.101HR, mean percent error = 11.3±36%). 相似文献
80.