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101.
The highly efficient treatment of azo dye contaminated wastewater from the textile industry is an important but challenging problem. Herein, polydimethylsiloxane (PDMS) microparticles, incorporating multiple-walled carbon nanotubes/titanium dioxide (MWCNTs/TiO2) nanocomposites, were successfully synthesized to treat wastewater containing Rhodamine B (RhB) dyes in a synergetic approach, by combining sorption and photocatalytic degradation. The surfactant wrapping sol–gel method was applied to synthesize MWCNTs/TiO2 nanocomposites with TiO2 nanoparticles evenly distributed on the surface of the MWCNTs. The PDMS microparticles were fabricated with an oil-in-water (O/W) single emulsion template, using needle-based microfluidic devices. MWCNTs/TiO2 nanocomposites (at a weight ratio of 1%, and 2%, respectively) were mixed with the PDMS precursor as the dispersed phase, and an aqueous solution of polyvinyl alcohol (PVA) was used as the continuous phase. Highly monodispersed microparticles, with average diameters of 692.7 μm (Coefficient of Variation, CV = 0.74%) and 678.3 μm (CV = 1.04%), were formed at an applied flow rate of the dispersed and continuous phase of 30 and 200 μL min−1, respectively. The fabricated hybrid microparticles were employed for the treatment of RhB, involving a dark equilibrium for 5 hours and UV irradiation for 3 hours. The experimental conditions of applied PDMS type, mass loading amount, treatment duration, photodegradation kinetics, initial concentration of pollutants and environmental pH values were investigated in this work. The PDMS microparticles with 2 wt% MWCNTs/TiO2 nanocomposites can exhibit a removal efficiency of 85%. Remarkably, an efficiency of 70% can be retained after the microparticles have been recycled and reused for 3 cycles. The PDMS–MWCNTs/TiO2 microparticles possess a superior performance over conventional treatment approaches for dye contaminated wastewater, especially in recyclability and the prevention of secondary pollution. This work provides a feasible and eco-friendly route for developing an efficient and low-cost microfluidic method for treating complicated water environmental systems.

PDMS–MWCNTs/TiO2 microparticles made by microfluidics can achieve 85% removal efficiency of RhB pollutant in wastewater via synergetic treatment.  相似文献   
102.
103.
During brain development, many factors influence the assembly and final positioning of cortical neurons, and this process is essential for proper circuit formation and normal brain function. Among many important extrinsic factors that guide the maturation of embryonic cortical neurons, the secreted neurotransmitter GABA has been proposed to influence both their migratory behaviour and their terminal differentiation. The full extent of the short‐term and long‐term changes in brain patterning and function caused by modulators of the GABA system is not known. In this study, we specifically investigated whether diazepam, a commonly used benzodiazepine that modulates the GABAA receptor, alters neuronal positioning in vivo, and whether this can lead to lasting effects on brain function. We found that fetal exposure to diazepam did not change cell positioning within the embryonic day (E)14.5 mouse cerebral cortex, but significantly altered neuron positioning within the E18.5 cortex. In adult mice, diazepam treatment affected the distribution of cortical interneurons that express parvalbumin or calretinin, and also led to a decrease in the numbers of calretinin‐expressing interneurons. In addition, we observed that neonatal exposure to diazepam altered the sensitivity of mice to a proconvulsant challenge. Therefore, exposure of the fetal brain to benzodiazepines has consequences for the positioning of neurons and cortical network excitability.  相似文献   
104.
This study compared nine resistance eccentric exercises targeting arm, leg, and trunk muscles in one session for changes in maximal voluntary isometric contraction strength (MVC), delayed onset muscle soreness (DOMS), plasma creatine kinase (CK) activity, and myoglobin (Mb) concentration after the first and second bouts. Fifteen sedentary men (20‐25 years) performed 5 sets of 10 eccentric contractions with 80% of MVC load for the elbow flexors (EF), elbow extensors (EE), pectoralis, knee extensors (KE), knee flexors (KF), plantar flexors (PF), latissimus, abdominis, and erector spinae (ES) in a randomized order and repeated the same exercises 2 weeks later. MVC decreased at 1 (16%‐57%) to 4 (13%‐49%) days, DOMS developed (peak: 43‐70 mm), and CK activity (peak: 23 238‐207 304 IU/L) and Mb concentration showed large increases after the first bout. The magnitude of decrease in MVC was greater (< 0.05) for EF, EE, and PEC than others and for KF than KE, PF, and ES. DOMS was greater (< 0.05) for EF, EE, and ES than others. Changes in all measures were smaller (< 0.05) after the second than the first bout, and the magnitude of the repeated bout effect was similar among the muscles. Plasma CK activity and Mb concentration did not increase significantly after the second exercise bout. It was concluded that muscle damage was greater for arm than leg muscles, and muscle proteins in the blood increased to a critical level after unaccustomed whole‐body resistance exercises, but the magnitude of damage was largely attenuated for all muscles similarly after the second bout.  相似文献   
105.
106.

Objective

This study seeks to examine how the extent of socioeconomic deprivation, racial and ethnic isolation, and health disadvantage differ among Medicare beneficiaries in Mississippi. Methods: Geographical information system (GIS) mappings are used in conjunction with cluster analysis to examine patterns of disparities in disease distribution, healthcare utilization and socioeconomic well-being among different counties in Mississippi.

Results

Results reveal that counties in these two clusters are markedly different in terms of socio-economic well-being but are somewhat similar in terms of disease distributions and healthcare utilization.

Conclusion

Addressing the geographic disparities in disease distribution and healthcare utilization that exist among the counties should be a public health priority. Specifically, health policies and programs should be renewed to target people living in counties that are either predominantly rural or predominantly Black or have higher percentages of population living below the poverty level.  相似文献   
107.
There are only limited reports on Punjabi’s health status in Malaysia. This cross-sectional study assessed the prevalence of metabolic syndrome (Mets) and its risk factors among 277 subjects recruited from the Malaysian Punjabi community. Overall prevalence of Mets was 43%, but 61% among females. Subjects classified with Mets had significantly (p?<?0.05) higher body mass index, visceral fat and percentage of body fat. Daily carbohydrate and glycemic index (GI) were also higher among Mets subjects (p?<?0.05). Logistics regression analysis showed that primary level of education (OR 5.57, CI 1.29–23.97, p?=?0.021) was a factor associated with Mets, followed by middle household income (OR 2.30, CI 1.01–5.20, p?=?0.046), GI (OR 1.03, CI 1.00–1.06, p?=?0.026), and age (OR 1.03, CI 1.00–1.05, p?=?0.023). Mets shows high prevalence among the studied Punjabi population, prompting the consideration of adequate preventive measures, primarily among lower socioeconomic groups.  相似文献   
108.
Objective: To evaluate whether early folic acid or multivitamin supplementation during pregnancy prevents diagnosis of hyperkinetic disorders (HKD), treatment for attention deficit hyperactivity disorder (ADHD), and ADHD-like behaviors reported by parents participating in the DNBC for children at age 7.

Methods: HKD diagnosis and ADHD medication use data were obtained from the Danish National Hospital, Central Psychiatric and Pharmaceutical registers. We estimated hazard ratios (HRs) for HKD diagnosis and ADHD medication use and risk ratios (RRs) for parent-reported ADHD behavior collected with the Strength and Difficulties Questionnaire (SDQ), comparing children whose mothers took folic acid or multivitamin supplements early in pregnancy defined as starting periconceptionally (4 weeks prior to their last menstrual period (LMP)) through 8 weeks after their LMP (4–8 weeks), to children whose mothers indicated no supplement use for the same entire period.

Results: We identified 384 children (1.1%) with a hospital diagnosis for HKD and 642 children (1.8%) treated with ADHD medication. We found no association between risk of HKD diagnosis or intake of ADHD medication and early maternal folic acid use. However, early multivitamin use was associated with an approximately 30% reduction in risk for HKD diagnosis (aHR: 0.70, 95% CI: 0.52–0.96) and 21% reduction in treatment with ADHD medication (aHR: 0.79, 95% CI: 0.62–0.98). We observed a reduced risk in parent-reported ADHD behaviors, but these results were attenuated after adjustment.

Conclusion: Our data suggest that multivitamin use in early pregnancy may reduce risk for HKD diagnosis and treatment for ADHD in the offspring.  相似文献   

109.
The variable life‐adjusted display (VLAD) is the first risk‐adjusted graphical procedure proposed in the literature for monitoring the performance of a surgeon. It displays the cumulative sum of expected minus observed deaths. It has since become highly popular because the statistic plotted is easy to understand. But it is also easy to misinterpret a surgeon's performance by utilizing the VLAD, potentially leading to grave consequences. The problem of misinterpretation is essentially caused by the variance of the VLAD's statistic that increases with sample size. In order for the VLAD to be truly useful, a simple signaling rule is desperately needed. Various forms of signaling rules have been developed, but they are usually quite complicated. Without signaling rules, making inferences using the VLAD alone is difficult if not misleading. In this paper, we establish an equivalence between a VLAD with V‐mask and a risk‐adjusted cumulative sum (RA‐CUSUM) chart based on the difference between the estimated probability of death and surgical outcome. Average run length analysis based on simulation shows that this particular RA‐CUSUM chart has similar performance as compared to the established RA‐CUSUM chart based on the log‐likelihood ratio statistic obtained by testing the odds ratio of death. We provide a simple design procedure for determining the V‐mask parameters based on a resampling approach. Resampling from a real data set ensures that these parameters can be estimated appropriately. Finally, we illustrate the monitoring of a real surgeon's performance using VLAD with V‐mask.  相似文献   
110.
BACKGROUND: There are limited numbers of studies focused on the using of platelet-rich plasma (PRP) combined with different types of bone substitutes in intra-bony defects. Aim: The purpose of this study was to evaluate the effect of bioactive glass graft material (BG) with and without PRP on the clinical healing of intra-bony defects. MATERIALS AND METHODS: Twenty-nine intra-bony defects were randomly treated with either PRP/BG or BG alone. Clinical parameters were recorded at baseline and repeated 9 months after surgery and surgical reentries were also performed. RESULTS: The results showed that both treatment modalities were effective. Pocket depth reduction of 3.60 +/- 0.51 mm, clinical attachment gain of 3.3 +/- 1.77 mm and defect fill of 3.47 +/- 0.53 mm were noted in the PRP/BG group, with 3.29 +/- 1.68, 2.86 +/- 1.56 and 3.36 +/- 0.55 mm improvements, respectively, noted for the BG group. None of the differences between the two treatment modalities were statistically significant. CONCLUSIONS: It is suggested that both PRP/BG combination and BG alone are effective in the treatment of intra-bony defects. The results also showed that using PRP with BG has no additional benefit in the reduction of pocket depth, clinical attachment gain and defect fill.  相似文献   
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