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61.
In this study combined heat and mass transfer by mixed convective flow along a moving vertical flat plate with hydrodynamic slip and thermal convective boundary condition is investigated. Using similarity variables, the governing nonlinear partial differential equations are converted into a system of coupled nonlinear ordinary differential equations. The transformed equations are then solved using a semi-numerical/analytical method called the differential transform method and results are compared with numerical results. Close agreement is found between the present method and the numerical method. Effects of the controlling parameters, including convective heat transfer, magnetic field, buoyancy ratio, hydrodynamic slip, mixed convective, Prandtl number and Schmidt number are investigated on the dimensionless velocity, temperature and concentration profiles. In addition effects of different parameters on the skin friction factor, , local Nusselt number, , and local Sherwood number are shown and explained through tables.  相似文献   
62.
Calcareous algae and microproblematica have been studied in the Middle Permian part of the Dalan Formation in Dena Mountain, Zagros, southwest Iran. Murgabian (=Wordian) microfossils are the most diversified. The assemblages encompass, among the dasycladales, Anthracoporella spectabilis, Epimastopora piae, Epimastoporella japonica, E. likana, Paraepimastopora? cf. densipora n. comb., Gyroporella cf. nipponica, G.? aff. fluegeli n. comb., G.? aff. symmetrica, G.? aff. digitula n. comb., Mizzia yabei; among the gymnocodiaceans, Gymnocodium bellerophontis, G. nodosum, Permocalculus cf. digitatus, P. forcepinus, P. cf. fragilis, P. plumosus, P. cf. solidus, Tauridium? sp.; among the “phylloid algae” Eugonophyllum? sp.; among the other incertae sedis algae Stacheoides sp., Ungdarella uralica, Fourstonella (Efluegelia) johnsoni, and among some microproblematica alternatively assigned to foraminifers or algae Aeolisaccus dunningtoni, Tubiphytes obscurus, Pseudovermiporella nipponica, P. sodalica, and P. longipora. Each taxon is briefly characterized, whereas a more detailed analysis of the epimastoporacean algae is given. Among them, the genera Epimastopora and Epimastoporella are emended. All the described microfossils have a relatively broad stratigraphic distribution in the Permian period but they are paleoecologically important. They are indeed confident micropaleontological Middle Permian proxies, particularly for shallow-marine, warm, well-oxygenated and relatively high-energy environments. They were affected by the end-Guadalupian crisis because they strongly decrease in the upper carbonate unit of the Dalan Formation and are not found in the Triassic sediments of the area.  相似文献   
63.
A mathematical model using simple concepts of repeated games is proposed to model the course and prognosis of factitious disorders. Although simple, the model seems capable of explaining the yet unknown mechanisms underlying the variable course of factitious disorders. One of the notable results of this study is the significant effect of involved physicians in the treatment process on the course of the disease. Particularly, the doctor's error rate in realizing whether the symptoms are real or factitious can considerably affect the course of the disease. This is the first paper to apply a mathematical model to factitious disorders.  相似文献   
64.
The Permian bryozoan fauna of the Surmaq Formation exposed in a section near Kuh-e Hambast (Hambast Mountains, central Iran) includes ten species. Four species (Fistulipora sawatai Sakagami 1999, Fistulipora takauchiensis Sakagami 1961, Fistulipora monticulosa Nikiforova 1933, and Eridopora parasitica, Waagen and Wentzel 1886) indicate a Middle Permian (Murgabian) age of the formation. Six additional taxa, three cystoporates Fistulipora sp. 1, Fistulipora sp. 2, and Fistuliporidae gen. et sp. indet., as well as three trepostomes Dyscritella sp., Trepostomata gen. et sp. indet. 1 and Trepostomata gen. et sp. indet. 2 could not be identified at the genus and species level. The investigated fauna refers to the Middle Permian of Thailand, Pakistan, Indonesia, and Japan.  相似文献   
65.

Background

The objective of this trial was to determine the effectiveness of 1.0% C31G (SAVVY) in preventing male-to-female vaginal transmission of HIV infection among women at high risk.

Methodology/Principal Findings

This was a Phase 3, double-blind, randomized, placebo-controlled trial. Participants made up to 12 monthly follow-up visits for HIV testing, adverse event reporting, and study product supply. The study was conducted between September 2004 and December 2006 in Lagos and Ibadan, Nigeria, where we enrolled 2153 HIV-negative women at high risk of HIV infection. Participants were randomized 1∶1 to SAVVY or placebo. The effectiveness endpoint was incidence of HIV infection as indicated by detection of HIV antibodies in oral mucosal transudate (rapid test) or blood (ELISA), and confirmed by Western blot or PCR testing. We observed 33 seroconversions (21 in the SAVVY group, 12 in the placebo group). The Kaplan-Meier estimates of the cumulative probability of HIV infection at 12 months were 0.028 in the SAVVY group and 0.015 in the placebo group (2-sided p-value for the log-rank test of treatment effect 0.121). The point estimate of the hazard ratio was 1.7 for SAVVY versus placebo (95% confidence interval 0.9, 3.5). Because of lower-than-expected HIV incidence, we did not observe the required number of HIV infections (66) for adequate power to detect an effect of SAVVY. Follow-up frequencies of adverse events, reproductive tract adverse events, abnormal pelvic examination findings, chlamydial infections and vaginal infections were similar in the study arms. No serious adverse event was attributable to SAVVY use.

Conclusions/Significance

SAVVY did not reduce the incidence of HIV infection. Although the hazard ratio was higher in the SAVVY than the placebo group, we cannot conclude that there was a harmful treatment effect of SAVVY.

Trial Registration

ClinicalTrials.gov NCT00130078  相似文献   
66.

Background

In this study, a hybrid treatment system (Fluidized Bed positioned in a biological reactor of an Activated Sludge process) was used to treat saline domestic wastewater. The performance of the mentioned hybrid system was compared with the conventional activated sludge. A pilot study was conducted, and Chemical Oxygen Demand (COD), Electrical Conductivity (EC), Total Dissolved Solids (TDS) and pH were measured to investigate treatment efficiency. Three saline wastewater samples with salt concentrations of 0.5, 1, and 1.5 % and detention times of 2, 4 and 6 h were loaded into both rectors of hybrid system and activated sludge.

Results

The results showed that Chemical Oxygen Demand (COD) removals at salt concentrations of 0.5, 1, 1.5 % were equal to 80, 71, 48.5 for the hybrid system and 62, 47.7, 26.5 for the activated sludge system respectively. Likewise, similar results obtained for other contamination indices indicating the superiority of the hybrid system in comparison to activated sludge system. Moreover, another advantage of the hybrid system was that the activated sludge needed sludge returning while sludge returning was not required in the hybrid system. In addition, by loading fixed rate of air into both systems, dissolved oxygen concentration in the hybrid reactor is higher than the conventional reactor.

Conclusions

Therefore, the hybrid system had a significantly higher efficiency than conventional reactor to treat saline domestic wastewater.
  相似文献   
67.
Due to recalcitrant nature of chickpea (Cicer arietinum L.) to androgenesis, the production of double haploid plants has been only reported by Grewal et al. (Plant Cell Rep 28:1289–1299, 2009) using some physical stresses such as anther centrifugation and electrical shock. In the present study, we successfully obtained haploid plants from cultured anthers of two chickpea cultivars, Bivanij and Arman, using high 2,4-D and silver nitrate containing media without applying of these time and labor consuming stresses. For induction of androgenesis, different concentrations of 2, 4-D (0, 2, 5 and 10 mg/l) and silver nitrate (0, 5, 10, 15, 25 and 50 mg/l) were used in embryo development medium. In Bivanij cultivar, anther induction medium containing 10 mg/l 2,4-D and 15 mg/l silver nitrate produced the highest number of embryos (0.188) and regenerated plants (0.1) per each cultured anther, while the highest frequencies of embryos (0.1) and regenerated plants (0.075 and 0.063) were obtained from Arman cultivar when 10 mg/l 2,4-D was combined with 15 and 50 mg/l silver nitrate in anther culture medium, respectively. In second part of this study, different cold (4 °C for 4 and 7 days) and heat (30 °C for 10 days, 32 °C for 2 days and 35 °C for 8 h) pretreatments were applied on cultured anthers of Bivanij cultivar. Incubation of cultured anthers at 32 °C for 2 days significantly enhanced the rate of embryo formation up to 0.222 embryos per each anther, while the highest number of regenerated plants/anther (0.0332) was obtained when cold treated anthers at 4 °C for 7 days incubated at 30 °C for 10 days. Taken together, these results provide a good basis for large-scale generation of DH plants in this important legume species.  相似文献   
68.

Background and Aim

The prevalence of metabolic syndrome (MS) increased in recent years in both adolescents and children groups. The aim of the study is evaluating the relationship between insulin and uric acid (UA) level in MS in adolescents

Materials and Methods

we studied 120 adolescence aged 10 to 19 in two groups: control group without metabolic syndrome and case group with metabolic syndrome. The Criteria of ATP III was considered as a diagnosis factor for metabolic syndrome.

Discussion

Various studies have been conducted in various populations to evaluate the relationship between UA level and MS in adolescents. Abdominal obesity, low HDL, hypertriglyceridemia and hypertension are associated with high UA level. In their analysis, the MS OR in UA level?4.9, 4.9-5.8 and ?5.8 mg/dl was 1, 2.53 and 9.03, respectively, which were higher than our findings in current study. Hyperinsulinemia caused by insulin resistance is one of the complications associated with MS, which puts individuals at risk of diabetes and cardiovascular events.

Results

Uric acid level in the Case group was significantly higher than the control group (p = 0.0001, 43.8±1.4 vs. 4.1±1 mg/dl, respectively). Insulin level was significantly higher in the case group in compare to the control group (p = 0.008, 9.8± 5.3 vs. 12.2±6 μU/ml, respectively).

Conclusion

The findings of this case-control study showed that adolescents with metabolic syndrome have a higher uric acid and insulin level in compare to normal subjects. We hypothesis that increase in serum insulin and uric acid level can be a risk factor in the development of metabolic syndrome.
  相似文献   
69.
Th1 cells play a central role in immunity to brucellosis, while the exact role of Th17 cells has remained unknown. This study aimed to evaluate the peripheral distributions of Th1 and Th17 cells and serum levels of IFN-γ, IL-17A and IL-22 cytokines in brucellosis patients. One hundred patients (36 acute, 41 under-treatment and 23 relapsed) and 30 age- and sex-matched healthy controls were included. The frequencies of Th1 and Th17 cells were determined by flow cytometric analysis. Serum levels of IFN-γ, IL-17A and IL-22 were measured by multi-analyte flow assay. Increased frequencies of Th1 and Th17 cells were observed in acute and relapsed brucellosis versus under-treatment patients and healthy controls (P < 0.05). The mean serum levels of IFN-γ were significantly elevated in acute and relapsed groups compared to under-treatment patients (P = 0.002 and P = 0.01 respectively). Acute patients showed higher levels of IL-22 than under-treatment (P = 0.008). Direct correlations were found between increased frequencies of Th1 and Th17 cells in acute and relapsed patients (P = 0.007 and P = 0.001 respectively) and between IL-17A and IL-22 in both groups of patients. Our findings indicate a cooperative role for Th1 and Th17 cells in immunity to brucellosis which is more evident during acute and relapse phases of brucellosis.  相似文献   
70.
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