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Zinc acetate is recrystallized as lumber-shaped tetragonal rods by a novel recrystallization technique. Subsequently, the recrystallized zinc acetate is converted into ZnO nanorods in a glass vial by the simplest and cheapest method without utilizing any expensive instrumentation. Carbon is doped in ZnO nanorods during the preparation ZnO nanorods without any extra steps, chemicals, or effort. The carbon-doped ZnO nanorods can be dispersed in a solvent at very high concentrations and are also stable for a very long time, which are comparatively higher than those of the other existing ZnO nanoparticles. The higher dispersion concentration and higher stability of ZnO nanoparticles are explained by a scheme that demonstrates the suspending mechanism of the ZnO nanoparticles at higher concentrations with higher stabilities in a solvent through the anchoring groups of carbon. No materials are used for surface modification; no surface coatings, ionic materials, or pH controlling materials are used to increase the dispersion concentration and stability. This is the first observation of the doped carbon playing a significant role in the dispersion of ZnO nanoparticles at higher concentrations by withholding them in the solvent. Therefore, doped carbon at the surface of ZnO nanoparticles prevents the self-aggregation of ZnO nanoparticles in the solution phase by interfacial barrier layers among ZnO nanorods and interfacial interactive layer between ZnO nanorod and solvent.

Dispersed ZnO hexagonal nanorods in ethanol solvent and its interfacial behavior in this liquid phase.  相似文献   
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Sixty-three patients with Salmonella typhi infections were randomly assigned to receive either ceftriaxone iv in single daily doses of 75 mg/kg for children and 3-4 g for adults for seven days or to receive 60 mg of chloramphenicol/kg a day orally or iv in four divided doses until defervescence and then 40 mg/kg a day to complete 14 d. In the ceftriaxone group, one death occurred, and two of seven patients still febrile 11 d after starting treatment were given chloramphenicol. In the chloramphenicol group, one death and one gastrointestinal perforation occurred. The probability of remaining febrile was similar for both groups during the first seven days but was significantly greater for patients receiving ceftriaxone during the 14-d period. Patients in the chloramphenicol group were more likely to be bacteremic on day 3. These results suggest that a seven-day course of once-daily ceftriaxone shows promise as an alternative to 14 d of chloramphenicol for treating typhoid fever.  相似文献   
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Purpose

Domestic violence (DV) by husbands or in-laws is a recognized problem in many countries and is associated with a wide range of adverse mental health outcomes. However, detailed knowledge on the relationship between DV experience and postpartum depression (PPD) is essential to design appropriate interventions. Therefore, this study assesses the relationship between maternal experience of DV perpetrated by husbands or in-laws and PPD in Bangladesh.

Methods

A cross-sectional survey was conducted from October to December 2019 among 497 mothers within the first 6 months postpartum who attended a health center in Rajshahi City Corporation, Bangladesh. Multivariable logistic regressions were performed to identify the associations after controlling for potential confounders.

Results

The prevalence of PPD in this sample was 34% within the first 6 months after birth; 58.6% of mothers reported having experienced any form of DV in their lifetime. Maternal experience of any form of DV (Adjusted Odds Ratio [AOR] = 1.87; 95% confidence interval [CI] = 1.19–2.93) was associated with PPD, as were experiences of any physical DV (AOR = 2.25; 95% CI = 1.40–3.59), emotional DV (AOR = 2.07; 95% CI = 1.34–3.19), and controlling behavior (AOR = 1.69; 95% CI = 1.08–2.66). Additionally, the likelihood of PPD significantly increased among women who experienced more forms of DV.

Conclusion

DV perpetrated by husband and/or in-laws is highly prevalent and significantly associated with PPD in Bangladesh. Strategies in developing interventions for improving maternal mental health should consider DV perpetrated by either husband or in-laws.

  相似文献   
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Multicentric reticulohistiocytosis (MRH) is a rare systemic inflammatory granulomatous disease that primarily manifests clinically with severe erosive arthritis and widespread papulonodular skin lesions but can involve multiple other organ systems. Despite the fact that this condition can become aggressive, debilitating as well as deforming with significant detrimental consequences, the etiology of this disease remains poorly understood. Moreover, the fact that MRH is such an uncommon disease has created an obstacle in the path of adequate clinical trials that are needed for better understanding of this phenomenon and for the development of treatment options for this patient population. In this review, we will attempt to discuss the epidemiology, pathophysiology, clinical features, associated conditions, differential diagnoses, diagnostic workup, and available treatments of MRH with the hope of creating a better understanding of this very challenging yet elusive disease process.  相似文献   
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Light scattering has been used for label-free cell detection. The angular light scattering patterns from the cells are unique to them based on the cell size, nucleus size, number of mitochondria, and cell surface roughness. The patterns collected from the cells can then be classified based on different image characteristics. We have also developed a machine learning (ML) method to classify these cell light scattering patterns. As a case study we have used this light scattering technique integrated with the machine learning to analyze staurosporine-treated SH-SY5Y neuroblastoma cells and compare them to non-treated control cells. Experimental results show that the ML technique can provide a classification accuracy (treated versus non-treated) of over 90%. The predicted percentage of the treated cells in a mixed solution is within 5% of the reference (ground-truth) value and the technique has the potential to be a viable method for real-time detection and diagnosis.  相似文献   
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