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81.
From 2010 to 2013, genotype I avian influenza A(H9N2) viruses of the G1-lineage were isolated from several poultry species in Egypt. In 2014, novel reassortant H9N2 viruses were detected in pigeons designated as genotype II. To monitor the subsequent genetic evolution of Egyptian A(H9N2) viruses, we characterized the full genomes of 173 viruses isolated through active surveillance from 2017 to 2022. In addition, we compared the virological characteristics and pathogenicity of representative viruses. Phylogenetic analysis of the HA indicated that all studied sequences from 2017–2021 were grouped into G1-like H9N2 viruses previously detected in Egypt. Phylogenetic analysis indicated that the Egyptian A(H9N2) viruses had undergone further reassortment, inheriting four genes (PB2, PB1, PA, NS) from genotype II, with their remaining segments deriving from genotype I viruses (these viruses designated as genotype III). Studying the virological features of the two most dominant genotypes (I and III) of Egyptian H9N2 viruses in vitro and in vivo indicated that both replicated well in mammalian cells, but did not show any clinical signs in chickens, ducks, and mice. Monitoring avian influenza viruses through surveillance programs and understanding the genetic and antigenic characteristics of circulating H9N2 viruses are essential for risk assessment and influenza pandemic preparedness.  相似文献   
82.
In the past, many studies have been conducted on the optimization of reinforced concrete (RC) structures. These studies have demonstrated the effectiveness of different optimization techniques to obtain an economical design. However, the use of optimization techniques to an obtain economical design is not so practical due to the difficulty in applying most of the optimization techniques to achieve an optimal solution. The RC beam is one of the most common structural elements encountered by a practising design engineer. The current study is designed to highlight the potential of the Solver tool in MS Excel as an easy-to-use option for optimizing the design of simply supported RC beams. A user-friendly interface was developed in a spreadsheet in which beam design parameters from a typical design can be entered and an economical design can be obtained using the Evolutionary Algorithm available in the MS Excel Solver tool. To demonstrate the effectiveness of the developed optimization tool, three examples obtained from the literature have been optimized. The results showed that up to 24% economical solution can be obtained by keeping the same material strengths that were assumed in the original design. However, if material strength is also considered as a variable, up to 44% of the economical solution can be obtained. A parametric study was also conducted to investigate the effect of different design variables on the economical design of simply supported RC beams and to derive useful rules of thumb for their design and proportioning, with the objective of cost minimization. The results of the parametric study suggest that the grade of the reinforcing steel is one of the most influential factors that affect the cost of simply supported RC beams. Practicing engineers can use the trends derived from this research to further refine their optimal designs.  相似文献   
83.
Aluminum waste-can management in Malaysia has recently become a serious environmental and public health issue, particularly in metropolitan areas. This has prompted the need to valorize these waste-cans into value-added products using the most economical and environmentally friendly techniques. In this study, the sol–gel technique was used to synthesize high-quality alumina from the aluminum waste-cans collected. From this method, the observed peaks of the synthesized alumina were identified as diaspore (α-AlO(OH)), boehmite (γ-AlO(OH)), aluminum oxide, or gamma-alumina (γ-Al2O3) crystalline structure and corundum. The morphological configuration, microstructure, and functional group properties of the synthesized alumina were evaluated. All the synthesized alumina exhibited a non-spherical shape and appeared to have hexagonal-like shape particles. Moreover, the XRD patterns of the synthesized alumina AL-6-30 and AL-12-30 exhibited a small angle (1–10°) with no XRD peak, which indicated a mesoporous pore structure with no long-range order. The overall results of γ-alumina synthesized from the aluminum waste-cans showed an optimal condition in producing a highly structured γ-alumina with excellent surface-area characteristics. The synthesized alumina exhibited stronger and highly crystalline functional characteristics almost comparable with the commercially available brands on the market.  相似文献   
84.
ABSTRACT: The European Network for Breast Development and Cancer (ENBDC) meeting on 'Methods in Mammary Gland Development and Cancer' has become an annual international rendezvous for scientists with interests in the normal and neoplastic breast. The fourth meeting in this series, held in April in Weggis, Switzerland, focused on proteomics, epigenetics, symmetric division, and metastasis.  相似文献   
85.
86.
Photoplethysmography is one of the optical techniques has been developed for experimental use in vasculardisease. It has several advantages over other traditional experimental approaches. Because of its non-invasive, safe, costeffectiveand easy-to-use properties, it is considered as a useful diagnostic tool. The further developments in the Photoplethysmographmay replace it among other tools used in the assessment of vascular diseases such as blood test and ultrasound.This overview discusses the different terminologies used for the photoplethysmograph and reveals the researchdiscontinuity among different disciplines. Moreover, it suggests standard terminologies as a resolution for a confusionpersisted for more than 50 years.  相似文献   
87.
Non-occlusive colonic ischaemia is a recognized albeit rare entity related to low blood flow within the visceral circulation and in most reported cases the right colon was affected. This is the second case report in the literature of extensive colonic necrosis following cardiac arrest and cardiopulmonary resuscitation (CPR). A 83-year-old Caucasian woman was admitted to our hospital due to a low energy hip fracture. On her way to the radiology department she sustained a cardiac arrest. CPR started immediately and was successful. A few hours later, the patient developed increasing abdominal distension and severe metabolic acidocis. An abdominal multidetector computed tomography (MDCT) scan was suggestive of intestinal ischaemia. At laparotomy, the terminal ileum was ischaemic and extensive colonic necrosis was found, sparing only the proximal third of the transverse colon. The rectum was also spared. The terminal ileum and the entire colon were resected and an end ileostomy was fashioned. Although the patient exhibited a transient improvement during the immediate postoperative period, she eventually died 24h later from multiple organ failure. Histology showed transmural colonic necrosis with no evidence of a thromboembolic process or vasculitis. Therefore, this entity was attributed to a low flow state within the intestinal circulation secondary to the cardiac arrest.  相似文献   
88.
89.
Osteoporosis is a major growing public health problem and it is clear that much needs to be done to bridge the gap between patients and practitioners. However, the educator must have a valid and reliable tool to evaluate the effectiveness of the teaching and learning that are done. Osteoporosis Knowledge Tool (OKT) provides an important strategy for healthcare professionals to start early intervention for patients who are at risk of osteoporosis. The aims of this study were to translate and examine the psychometric properties of the Malaysian version of the Osteoporosis Knowledge Tool (OKT-M) among 250 type 2 diabetes patients and to assess factors that affect diabetic patients’ osteoporosis knowledge. The OKT English version was translated and validated using the internationally accepted and recommended methodology. The sensitivity and specificity of OKT-M was calculated using receiver operating characteristic curve analysis. The face and content validity showed acceptable results. Internal consistency, test–retest reliability, mean difficulty factor and discriminatory power values were 0.72, 0.83, 0.47 ± 0.16 and 0.96, respectively. The cut-off point of the OKT-M to predict osteoporosis/osteopenia was 14 with optimal sensitivity (84.1 %) and specificity (85.5 %). Regression analysis revealed that health belief, self-efficacy and some demographic data had an impact on the OKT-M. The findings of this validation study indicate that the OKT-M is a reliable and valid tool with good psychometric properties in the Malaysian setting. The OKT-M is an appropriate tool for application in clinical setting to identify patients need for a bone health-promoting intervention regarding lifestyle behaviour changes.  相似文献   
90.
Modern medical simulation technology (MST) debuted in 1960 with the development of Resusci Annie (Laerdal 2007), which assisted students in the acquisition of proper ventilation and compression techniques used during basic life support. Following a steady stream of subsequent technological advances and innovations, MST manufacturers are now able to offer training aids capable of facilitating innovative learning in such diverse areas as human patient simulators, simulated clinical environments, virtual procedure stations, virtual medical environments, electronic tutors, and performance recording. The authors list a number of the most popular MSTs presently available while citing evaluative efforts undertaken to date regarding the efficacy of MST to the medical profession. They conclude by proposing a variety of simulation innovations of prospective interest to both medical and technology personnel while offering healthcare administrators a series of recommended considerations when planning to integrate MST into existing medical systems.  相似文献   
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