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1.
Mixed convection peristaltic flow of Jeffrey nanofluid in a channel with compliant walls is addressed here. The present investigation includes the viscous dissipation, thermal radiation and Joule heating. Whole analysis is performed for velocity, thermal and concentration slip conditions. Related problems through long wavelength and low Reynolds number are examined for stream function, temperature and concentration. Impacts of thermal radiation, Hartman number, Brownian motion parameter, thermophoresis, Joule heating and slip parameters are explored in detail. Clearly temperature is a decreasing function of Hartman number and radiation parameter.  相似文献   
2.
BackgroundSeveral developing countries like Pakistan step into Sustainable Development Goals period with crucial maternal and child health needs that need to be addressed for improving health outcomes among people. We aim to explore existent socio-economic disparities in use of family planning methods (FPM) among Pakistani women, and compare any such inequalities between the years 2006 and 2013.SettingPakistan Demographic and Health Surveys (PDHS) 2006–7 (n = 9177) and the most recent 2012–13(n = 13558) data were used to conduct secondary analysis. Participants were ever married women aged between 15 and 49 years. Socio-economic status was assessed by the education level and wealth index. Inequalities were measured through Odds Ratio (OR), Relative Index of inequality (RII), and Slope index of inequality (SII) on non-use of FPM.ResultsAlthough the prevalence of FPM use has increased over time (28% in 2006 versus 54% in 2013), the socio-economic inequalities persistently exist. Comparing results of PDHS 2006 with PDHS 2013, education related absolute inequalities among urban dwellers increased from -0.41 (95% CI -0.67, -0.13, p-value < 0.01) to -0.83 (95% CI -1.02, -0.63, p-value < 0.01); and increased from -0.93 (95% CI -1.21, -0.64, p-value < 0.01) to -0.98 (95% CI -1.20, -0.76, p-value < 0.01) among rural dwellers. Similarly wealth related absolute inequalities are also existent.ConclusionsAlthough the FPM use has increased over time, but it is important to note that socio-economic gap in use of FPM persists. Such differences have disadvantaged the poor and the illiterate. Family planning programs may target the disadvantaged subgroups for ensuring well-being of women and children in Pakistan.  相似文献   
3.
The effect of various doses of sodium tellurite (0.4, 0.8, and 2.0 mg/kg body weight, orally) on the activity of antioxidant enzymes (glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and catalase) and content of glutathione and thiobarbituric acid reactive substances (TBARSs) in the cerebrum, cerebellum, and brainstem of male albino mice was studied after 15 d of treatment. All of the doses of tellurium (0.4, 0.8, and 2.0 mg/kg body weight, orally) have depleted the activity of antioxidant enzymes and the content of glutathione dose dependently in the cerebrum, cerebellum, and brainstem and it was significant with the dose of 2.0 mg/kg. On the other hand, the 2.0-mg/kg dose of tellurium has significantly elevated the content of TBARSs in the cerebrum and cerebellum. The 0.8-mg/kg dose of tellurium has significantly depleted the activities of glutathione peroxidase in the cerebrum and brainstem, glutathione-S-transferase in the cerebrum and cerebellum, catalase in the brainstem, and the content of glutathione in the cerebrum and cerebellum. In contrast, this dose has significantly elevated the content of TBARSs in the cerebrum and cerebellum. However, the depletion in the activity of glutathione reductase with various doses of sodium tellurite was not significant in any brain part of mice. The result suggests that sodium tellurite differentially affects the antioxidant status within various parts of the mice brain.  相似文献   
4.
A number of substrates were tested for the cultivation of microorganisms to produce a host of enzymes. The effect of different substrates (wheat and rice straw, sugar cane waste, wood waste), incubation temperatures (20–40°C), initial pH levels (3.5–9.0), incubation periods (0–72 hours) and nitrogen sources (ammonium sulfate, urea, peptone, yeast extract, sodium nitrate) on growth and α-amylase activity was studied for the native and mutant strains. Maximum enzyme activity was observed at 1.5% wheat straw for Aspergillus niger FCBP-198 and An-Ch-4.7 and at 2% wheat straw for An-UV-5.6, with sodium nitrate as a principle nitrogen source. The optimum temperature for maximum enzyme activity was 30°C for the parental strain, while An-UV-5.6 and An-Ch-4.7 thrived well at 32.5°C. The best conditions of pH and incubation duration were 4.5 and 48 hours, respectively, for all the strains. Mass production under preoptimized growth conditions demonstrated the suitability of wheat straw for swift mycelial colonization and viability.  相似文献   
5.
Adsorption is an environmental friendly process for removal and/or recovery of heavy metals from wastewater. In recent years, it has been substantiated as a popular technique to treat industrial waste effluents, with significant advantages. In this work, batchwise removal of chromium (III) ions from water by Polyalthia longifolia leaves was studied as a function of adsorbent dose, pH, contact time, and agitation speed. Surface characteristics of the leaves were evaluated by recording IR spectra. The Langmuir, Freundlich, and Temkin adsorption isotherms were employed to explain the sorption process. It was found that one gram of leaves can remove 1.87 mg of trivalent chromium when working at pH 3.0. It has been concluded that Polyalthia longifolia leaves can be used as cost-effective and benign adsorbents for removal of Cr(III) ions from wastewater.  相似文献   
6.
The effect of 0.05, 0.1, and 0.2 mg sodium selenite/kg body weight ip on the activities of neurobehavioral, acetyl cholinesterase, monoamine oxidase, and the content of dopamine and its metabolites in circadian rhythm centers of male Wistar rats was studied after 7 d of treatment. The results show an appreciable increase in locomotion, stereo-events, distance traveled, and average speed at the dose of 0.1 and 0.2 mg sodium selenite/kg. The data have shown hyperactivity of animals with various doses of sodium selenite, and it was significant and dose-dependent after 3 d of treatment. The activity of acetylcholinesterase (AChE) was inhibited dose dependently, and it was significant in preoptic area with 0.1 or 0.2 mg sodium selenite/kg. Conversely, in the posterior hypothalamus its activity was significantly elevated with the dose of 0.2 mg sodium selenite/kg, but its alteration in brain stem was not significant. Monoamine oxidase (MAO) activity was increased in preoptic area with the dose of 0.1 mg sodium selenite/kg, but its alteration in posterior hypothalamus and brain stem was not significant. The content of dopamine (DA), 3,4-dihydroxyphenyl acetic acid (DOPAC), and homovanilic acid (HVA) was elevated dose dependently and it was significant with the doss of 0.1 and 0.2 mg sodium selenite/kg, but the content of DOPAC and HVA in posterior hypothalamus was not significant with the dose of 0.1 mg sodium selenite/kg.  相似文献   
7.
The present work examined morphological and physiological aspects of osmoregulation in some differently adapted populations of Typha domingensis. Six populations of T. domingensis were grown in waterlogged conditions under four levels of nickel (0, 50, 100 and 1500 mg/kg of Ni). The Ni tolerance was explored on the basis of different characteristics of shoots. Along with the increasing level of Ni stress, all populations showed an increment of proline and glycinebetaine content, low photosynthetic and transpiration rates and decreased chlorophyll content. Analyzed morphological parameters revealed possible adaptations to deal with Ni stress. The less tolerant Sahianwala population produced more aerenchyma, less accumulation of osmolytes and reduced shoot fresh weight under Ni stress than the tolerant ones. Our results suggested that T. domingensis has the capacity to survive under Ni stress and could be used for the absorption of toxic metal ions from industrially polluted water.  相似文献   
8.
Vascular cross-clamping is applied in many cardiovascular surgeries such as coronary bypass, aorta repair and valve procedures. Experimental studies have found that clamping of various degrees caused damage to arteries. This study examines the effects of popular clamps on vessel wall. Models of the aorta and clamp were created in Computer Assisted Design and Finite Element Analysis packages. The vessel wall was considered as a non-linear anisotropic material while the fluid was simulated as Newtonian with pulsatile flow. The clamp was applied through displacement time function. Fully coupled two-way solid–fluid interaction models were developed. It was found that the clamp design significantly affected the stresses in vessel wall. The clamp with a protrusion feature increased the overall Von Mises stress by about 60% and the compressive stress by more than 200%. Interestingly, when the protrusion clamp was applied, the Von Mises stress at the lumen (endothelium) side of artery wall was about twice that of the outer wall. This ratio was much higher than that of the plate-like clamp which was about 1.3. The flow reversal process was demonstrated during clamping. Vibrations, flow and wall shear stress oscillations were detected immediately before total vessel occlusion. The commonly used protrusion clamp increased stresses in vessel wall, especially the compressive stress. This design also significantly increased the stresses on endothelium, detrimental to vessel health. The present findings are relevant to surgical clamp design as well as the transient mechanical loading on the endothelium and potential injury. The deformation and stress analysis may provide valuable insights into the mode of tissue injury during cross-clamping.  相似文献   
9.
Normal cellular metabolism produces oxidants that are neutralized by the cells' antioxidant enzymes and antioxidants taken from outside. An imbalance between oxidant and antioxidant has been postulated to lead to the neurodegeneration in the ischemic condition. In this study, we have demonstrated the prevention or slowdown of neuronal injury in middle cerebral artery occlusion (MCAO) by sodium selenite. Rats were pretreated with 0.05, 0.1, and 0.2 mg/kg body wt of sodium selenite for 7 d. The rats of group I (sham) and group II (ischemia) were pretreated with physiological saline for 7 d. On d 8, MCAO was induced for 2 h in, the right side of brain of group II, III, IV, and V rats. Brains were dissect out after 22 h of reperfusion and washed with chilled physiological saline. The right cerebral hemisphere was used for the preparation of mitochondria. The activity of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, and monoamine oxidase (MAO-A and MAO-B) was depleted significantly; conversely, the activity of poly(ADP-ribosyl) polymerase was elevated significantly as compared to the sham, and the pretreatment of the animals with different doses of sodium selenite has protected the activity of these enzymes significantly. The content of glutathione was decreased significantly, whereas the level of lipid peroxidation was increased significantly in the mitochondria of MCAO as compared to the sham group, and pretreatment with different doses of sodium selenite has protected their levels significantly as compared to the MCAO group. It is concluded that selenium, which is an essential part of our diet, might be helpful in protection against neurodegeneration in cerebral ischemia.  相似文献   
10.
The effect of sodium selenite (0.05, 0.1, and 0.2 mg/kg body weight, ip) on the contents of lipids (phospholipids, cholesterol, esterified fatty acids, gangliosides), thiobarbituric acid reactive substance (TBARS), and thiol group in circadian rhythm centers (preoptic area, brainstem, and posterior hypothalamus) of male Wistar rats was studied after 7 d of treatment. The content of phospholipids was elevated significantly with a dose of 0.1 mg/kg of selenite in the preoptic area and brainstem, but a 0.2-mg/kg dose has depleted its level significantly in these regions. The alteration of phospholipids in posterior hypothalamus was not significant with three doses of sodium selenite. The level of cholesterol in the preoptic area was inhibited significantly with a dose of 0.05 mg/kg sodium selenite, but its level was elevated significantly with a dose of 0.2 mg/kg selenite in the preoptic area and brainstem. Alteration with three doses of sodium selenite in the posterior hypothalamus was not significant. The ganglioside level in the preoptic area and brainstem was elevated significantly with a 0.1-mg dose of sodium selenite; conversely, a 0.2 mg dose of sodium selenite caused a significant depletion on its content in these areas. In the posterior hypothalamus, the ganglioside level was depleted significantly with a dose of 0.1 mg, but elevated significantly with a dose of 0.2 mg of sodium selenite. The level of esterified fatty acids was decreased significantly in the preoptic area and brainstem with a dose of 0.1 mg/kg sodium selenite, but in these regions, its level was elevated with a dose of 0.2 mg/kg sodium selenite and its elevation was significant in the preoptic area. In the posterior hypothalamus, the alteration of esterified fatty acids with three doses of sodium selenite was not significant. The effect of 0.1 and 0.2 mg/kg sodium selenite on the TBARS level and thiol group in sleep centers was significantly opposite to the wakefulness center. A sodium selenite dose of 0.1 mg/kg had depleted the content of TBARS in the preoptic area and brainstem but elevated the content of the thiol group significantly in the posterior hypothalamus. On the other hand, a 0.2-mg/kg dose of sodium selenite has significantly elevated the content of TBARS but depleted the content of the thiol group significantly in the posterior hypothalamus. No dose-dependent alteration was observed on the content of lipids, TBARS, and thiol group in the circadian rhythm centers of rats.  相似文献   
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