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51.
The health care delivery system in Pakistan is in a process of rapid growth, and it consists of public and private sectors. The provincial government is preliminarily responsible for providing health care facilities within its province except in federally administered areas. In Pakistan, there are three tiers of governmental healthcare delivery systems, which comprise government, semi-government, and parastatal organizations. The purpose of this study is to understand the rapid increase in influx of patients in major city hospitals of the Punjab province. The reasons for patient flow towards the major city areas can vary, but our point of focus is mainly on those patients who are prescribed to get a computed tomography (CT) scan done for better diagnosis and early treatment, including but not limited to roadside accident cases. The study targets the define, measure, analyze, improve and control (DMAIC) problem solving approach to assess the potential cause of CT patient flow and the challenges that the health department is facing to cater to such a patient niche and process while minimizing the congestion in city government hospitals. The approach in this study summarizes with numerous quality tools like Voice of Customer (VOC) which is customer feedback, Customer Output Process Input and Supplier (COPIS) processes use for high-level process map to know what your customer value, Approver Resource Member Interested (ARMI) chart which is use to analyze the stakeholders on management of the project, evaluation with the help of fishbone diagram and house of quality, and for process improvement methodology we use the team brainstorming technique and the kaizen 5-why technique. The technique came up with an idea of a public-private partnership (PPP) project—partnership between public agency and private firm, as the health care industry in Punjab province is going through budgetary issues. In a PPP project, the Government will allocate the space to a private firm to build the facility on their own and provide quality service for CT scan diagnosis to the public of Punjab. The study identified the top 10 critical factors that the patients have expected from the government to be provided on priority. The Kaizen process improvement methodology has been adopted to provide the possible solution of government budgetary issues. The set of tools in this study can be adopted by other PPP projects to enhance the project performance.  相似文献   
52.
A healthy eating environment in the school setting is crucial to nurture the healthy eating pattern for youth. Thus, it helps to combat the obesity issue. However, the impact of healthy school environment on healthy eating habits among Asian adolescents is scarce and less clear. This clustered randomised-control study has two objectives. The first objective was to evaluate the changes in adolescents’ dietary intake after the interventions for all arms (control; healthy cooking training only; subsidization with healthy cooking training). The second objective was to compare the effect of subsidization with healthy cooking training and healthy cooking training only with the control arm on adolescents’ dietary intakes. This study consisted of 340 secondary school students aged 14 years in rural and urban Malaysia. A total of two arms of intervention and one arm of control were included. Intervention one focused on healthy cooking preparation for the canteen and convenience shop operators. Intervention two included subsidization for fruits and vegetables with a healthy cooking preparation training for the canteen and suggestions on providing healthy options to the convenience shop operators. The outcome measured was changes to dietary intake. It was measured using a three-day dietary history pre- and post-intervention. A paired-t test was used to evaluate the outcome of intervention programmes on dietary changes for all arms (control, intervention one and two). An ANCOVA test was used to investigate the effect of providing subsidization and healthy cooking preparation training to the canteen and convenience shop operators on adolescents’ dietary intakes as compared to the control arm. Overall, the reduction in energy and carbohydrates for all arms were observed. Interestingly, fat intake was significantly increased after the four-week intervention programme under healthy cooking intervention but not in the food subsidization group. When comparing between control, healthy cooking training only and subsidization with the healthy cooking training arm, there was no significant changes between arms. A robust intervention to include subsidization of healthy foods for intervention programmes at schools in a larger scale study is needed to confirm this finding.  相似文献   
53.
The development of cost-effective co-catalysts of high photocatalytic activity and recyclability is still a challenge in the energy transformation domain. In this study, 0D/2D Schottky heterojunctions, consisting of 0D ZnO and 2D Ti3C2, were successfully synthesized by the electrostatic self-assembling of ZnO nanoparticles on Ti3C2 nanosheets. In constructing these heterojunctions, Ti3C2 nanosheets acted as a co-catalyst for enhancing the transfer of excitons and their separation to support the photocatalytic response of ZnO. The as-prepared ZnO/Ti3C2 composites demonstrate an abbreviated charge transit channel, a huge interfacial contact area and the interfacial electrons’ transport potential. The extended optical response and large reactive area of the ZnO/Ti3C2 composite promoted the formation of excitons and reactive sites on the photocatalyst’s surface. The ZnO/Ti3C2 Schottky heterojunction showed significantly high photocatalytic activity for hydrogen production from a water–ethanol solution under the light illumination in the visible region. The hydrogen evolution overoptimized the ZnO/Ti3C2 composition with 30 wt.% of Ti3C2, which was eight times higher than the pristine ZnO. These findings can be helpful in developing 0D/2D heterojunction systems for photocatalytic applications by utilizing Ti3C2 as a low-cost co-catalyst.  相似文献   
54.
The evaluation of the shear capacity of an FRP-strengthened reinforced-concrete beam is challenging due to the complex interaction between different contributions provided by the concrete, steel stirrup and FRP reinforcement. The shape of the beam and the FRP inclination can have paramount importance that is not often recognized by the models that are suggested by codes. The interaction among different resisting mechanisms has a significant effect on the shear capacity of beams, since it can cause a reduction in the efficiency of some resisting mechanisms. A comparative study of the performance in the shear resistance assessment provided by three models with six different effectiveness factors (R) is performed, considering different cross-section shapes, FRP wrapping schemes, inclination and anchorage systems. The results revealed that the cross-section shape, the FRP inclination and the efficiency of the FRP anchorages have a significant effect on the shear strength of beams. The analysis results show that the three models are able to provide an accurate average estimation of shear strength (but with a coefficient of variation up to 0.35) when FRP reinforcement orthogonal to the beam axis is considered, while a significant underestimation (up to 19%) affected the results for inclined FRP reinforcement. Moreover, all the models underestimated the resistance of beams with a T section.  相似文献   
55.
Background:Mesenteric panniculitis (MP) is a non-specific, localized inflammation at the mesentery of small intestines which often gets detected on computed tomography. An association with malignant neoplasms remains unclear. We performed a systematic review and meta-analysis to examine the association of malignancy with MP.Methods:MEDLINE, EMBASE, Web of Science, and Cochrane databases were searched for articles published from inception to 2020 that evaluated the association of malignant neoplasms with MP in comparison with control groups. Using random-effects method, a summary odds ratio (OR) estimate with 95% confidence intervals for malignant neoplasms in MP was estimated.Results:Four case-control studies reporting data on 415 MP patients against 1132 matched-controls met inclusion criteria and were analyzed. The pooled OR for finding a malignant neoplasm in patients with MP was 0.907 (95% CI: 0.688–1.196; P = .489). The heterogeneity was mild and non-significant. Also, there was no heightened risk of any specific type of malignancy with MP. Three more case-series with unmatched-control groups (MP: 282, unmatched-controls: 17,691) were included in a separate analysis where the pooled OR of finding a malignant neoplasm was 2.963 (95% CI: 1.434–6.121; P = .003). There was substantial heterogeneity in this group.Conclusion:This meta-analysis of matched controlled studies proves absence of any significant association of malignant neoplasms with MP. Our study also demonstrates that the putative association of malignancy with MP is mainly driven by uncontrolled studies or case-series.  相似文献   
56.
Photocatalytic materials attract immense scientific interest due to their possible applications in energy harvesting. These applications are strongly dependent on the material''s band gap and efficient visible light absorption, which ultimately relies on the underlying electronic structure of the material. In this work, we have theoretically studied the electronic and optical response of a Cu3P semiconductor. We have used Density Functional Theory (DFT), and the Many-Body Perturbation Theory (MBPT) based Bethe–Salpeter Equation (BSE). Cu3P has intriguing band gap nature, as DFT predicts a semi-metallic state which was corrected by employing the Hubbard potentials. Only astronomically large values of Hubbard potentials reproduced the semiconducting state of Cu3P. The optical response of the material is computed within a Random Phase Approximation (RPA) and using the BSE on top of DFT+U wavefunctions and on the ground state computed with the PBE0 functional. The BSE captures the excitonic physics, and the optical absorption obtained from it was red-shifted compared to the RPA, which shows the significance of electron–hole interactions in Cu3P. The comparison of the BSE with experiments suggests that BSE@PBE0 reproduces the optical absorption much more closely to the experimental data.

The optical absorption from BSE@PBE0 is in better agreement with the experiment than BSE@DFT+U. The electron–hole interaction and strong correlation between electrons play a vital role in the optoelectronic response of Cu3P.  相似文献   
57.
This research demonstrates the use of biogenic silica derived from bamboo leaf ash as a support for iron oxide nanoparticles. The preparation includes silica extraction from bamboo leaf ash and iron oxide nanoparticle impregnation into the silica gel under hydrothermal conditions, which is followed by calcination at 400 °C for 2 h. The physicochemical characterization includes X-ray diffraction analysis, gas sorption analysis, scanning electron microscopic analysis and transmission electron microscopic analysis. The light absorption capability and the band gap energy of the materials were determined by diffuse-reflectance UV–visible spectrophotometry. The materials obtained by varying the Fe content to 5 and 10% wt. were evaluated in rhodamine B photocatalytic degradation and photooxidation systems. It was found that the materials have a combined hematite and magnetite nanostructure, with the ratio of 9:10, and the particle sizes range from 10 to 40 nm. With a band gap energy of 2.27 eV, the prepared materials produce the successive photocatalytic degradation of rhodamine B. It was clarified that the formation of composite enhances stability and reusability of photocatalyst as shown by the stable initial rate at wide pH range and reuse for 5 cycles. Degradation mechanism is enhanced by the addition of H2O2 as an oxidant, and the investigation of the effect of scavengers shows that the degradation rate not only depends on radical formation but also on other species related to the formation of oxidizing agent.  相似文献   
58.
Acute toxicity of hexavalent chromium in isolated teleost hepatocytes   总被引:5,自引:0,他引:5  
Acute toxic effects of hexavalent chromium [Cr(VI)], a widely recognised carcinogenic, mutagenic and redox active metal, were investigated in isolated hepatocytes of goldfish (Carassius auratus). Exposure to 250 microM Cr(VI) induced a significant decrease of cell viability from 94% in controls to 88% and 84% after 30 min and 4 h of exposure, respectively. Cr-toxicity was associated with a concentration-dependent stimulation of the formation of reactive oxygen species (ROS). As one potential source of ROS formation we identified the lysosomal Fe(2+) pool, since the ferric ion chelator deferoxamin inhibited ROS formation by approximately 15%. Lysosomal membranes remained nevertheless intact during Cr-exposure, as determined from neutral red retention in this compartment. Another significant source of ROS appear to be the mitochondria, where a presumably uncoupled increase of respiration by 20-30% was triggered by the metal. Inhibition of mitochondrial respiration by cyanide caused an approximately 40% decrease of Cr-induced ROS-formation, whereas the uncoupling agent carbonyl cyanide m-chlorophenyl hydrazine was without effect. Cellular Ca(2+) homeostasis was not disturbed by Cr(VI) and thus played no role in this scenario. Overall, our data show that Cr(VI) is acutely toxic to goldfish hepatocytes, and its toxicity is associated with the induction of radical stress, presumably involving lysosomes and mitochondria as important sources of ROS formation.  相似文献   
59.
Compressive strength (CS) and splitting tensile strength (STS) are paramount parameters in the design of reinforced concrete structures and are required by pertinent standard provisions. Robust prediction models for these properties can save time and cost by reducing the number of laboratory trial batches and experiments needed to generate suitable design data. Silica fume (SF) is often used in concrete owing to its substantial enhancements of the engineering properties of concrete and its environmental benefits. In the present study, the M5P model tree algorithm was used to develop models for the prediction of the CS and STS of concrete incorporating SF. Accordingly, large databases comprising 796 data points for CS and 156 data records for STS were compiled from peer-reviewed published literature. The predictions of the M5P models were compared with linear regression analysis and gene expression programming. Different statistical metrics, including the coefficient of determination, correlation coefficient, root mean squared error, mean absolute error, relative squared error, and discrepancy ratio, were deployed to appraise the performance of the developed models. Moreover, parametric analysis was carried out to investigate the influence of different input parameters, such as the SF content, water-to-binder ratio, and age of the specimen, on the CS and STS. The trained models offer a rapid and accurate tool that can assist the designer in the effective proportioning of silica fume concrete.  相似文献   
60.
Background: The interaction of aging-related, genetic, and environmental factors is thought to contribute to the etiology of late-onset, sporadic Alzheimer’s disease (AD). We previously reported that serum levels of p,p′-dichlorodiphenyldichloroethylene (DDE), a long-lasting metabolite of the organochlorine pesticide dichlorodiphenyltrichloroethane (DDT), were significantly elevated in patients with AD and associated with the risk of AD diagnosis. However, the mechanism by which DDT may contribute to AD pathogenesis is unknown.Objectives: This study sought to assess effects of DDT exposure on the amyloid pathway in multiple in vitro and in vivo models.Methods: Cultured cells (SH-SY5Y and primary neurons), transgenic flies overexpressing amyloid beta (Aβ), and C57BL/6J and 3xTG-AD mice were treated with DDT to assess impacts on the amyloid pathway. Real time quantitative polymerase chain reaction, multiplex assay, western immunoblotting and immunohistochemical methods were used to assess the effects of DDT on amyloid precursor protein (APP) and other contributors to amyloid processing and deposition.Results: Exposure to DDT revealed significantly higher APP mRNA and protein levels in immortalized and primary neurons, as well as in wild-type and AD-models. This was accompanied by higher levels of secreted Aβ in SH-SY5Y cells, an effect abolished by the sodium channel antagonist tetrodotoxin. Transgenic flies and 3xTG-AD mice had more Aβ pathology following DDT exposure. Furthermore, loss of the synaptic markers synaptophysin and PSD95 were observed in the cortex of the brains of 3xTG-AD mice.Discussion: Sporadic Alzheimer’s disease risk involves contributions from genetic and environmental factors. Here, we used multiple model systems, including primary neurons, transgenic flies, and mice to demonstrate the effects of DDT on APP and its pathological product Aβ. These data, combined with our previous epidemiological findings, provide a mechanistic framework by which DDT exposure may contribute to increased risk of AD by impacting the amyloid pathway. https://doi.org/10.1289/EHP10576  相似文献   
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