21 research outputs found

    The Insecticidal Activity of Tea Tree Oil (Melaleuca Alternifolia) Against the Common Pest in Mummies (Dermestes Maculatus)

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    Egyptian mummies show different signs of deterioration caused by insects, such as missing parts, gaps and accumulated dust. Dermestes maculatus is one of the serious pests that cause damage to Egyptian mummies. To assess the insecticidal activity of tea tree oil against the larvae of the museum insect pest Dermestes maculatus (isolated from Egyptian mummies) we tested it under different concentration and treatment times by the bioassay methods. Our results showed that tea tree oil diluted in ethanol was highly toxic to Dermestes maculatus larvae. Insecticidal activity depended on both concentration and exposure time. By increasing the concentration level and the exposure time we obtained a higher mortality rate

    Multi-objective optimization of switched reluctance machine design using Jaya algorithm (MO-Jaya)

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    The switched reluctance machine (SRM) design is different from the design of most of other machines. SRM has many design parameters that have non-linear relationships with the performance indices (i.e., average torque, efficiency, and so forth). Hence, it is difficult to design SRM using straight forward equations with iterative methods, which is common for other machines. Optimization techniques are used to overcome this challenge by searching for the best variables values within the search area. In this paper, the optimization of SRM design is achieved using multi-objective Jaya algorithm (MO-Jaya). In the Jaya algorithm, solutions are moved closer to the best solution and away from the worst solution. Hence, a good intensification of the search process is achieved. Moreover, the randomly changed parameters achieve good search diversity. In this paper, it is suggested to also randomly change best and worst solutions. Hence, better diversity is achieved, as indicated from results. The optimization with the MO-Jaya algorithm was made for 8/6 and 6/4 SRM. Objectives used are the average torque, efficiency, and iron weight. The results of MO-Jaya are compared with the results of the non-dominated sorting genetic algorithm (NSGA-II) for the same conditions and constraints. The optimization program is made in Lua programming language and executed by FEMM4.2 software. The results show the success of the approach to achieve better objective values, a broad search, and to introduce a variety of optimal solutions

    Finite element based overall optimization of switched reluctance motor using multi-objective genetic algorithm (NSGA-II)

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    The design of switched reluctance motor (SRM) is considered a complex problem to be solved using conventional design techniques. This is due to the large number of design parameters that should be considered during the design process. Therefore, optimization techniques are necessary to obtain an optimal design of SRM. This paper presents an optimal design methodology for SRM using the non-dominated sorting genetic algorithm (NSGA-II) optimization technique. Several dimensions of SRM are considered in the proposed design procedure including stator diameter, bore diameter, axial length, pole arcs and pole lengths, back iron length, shaft diameter as well as the air gap length. The multi-objective design scheme includes three objective functions to be achieved, that is, maximum average torque, maximum efficiency and minimum iron weight of the machine. Meanwhile, finite element analysis (FEA) is used during the optimization process to calculate the values of the objective functions. In this paper, two designs for SRMs with 8/6 and 6/4 configurations are presented. Simulation results show that the obtained SRM design parameters allow better average torque and efficiency with lower iron weight. Eventually, the integration of NSGA-II and FEA provides an effective approach to obtain the optimal design of SRM

    Global economic burden of unmet surgical need for appendicitis

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    Background: There is a substantial gap in provision of adequate surgical care in many low-and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods: Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results: Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US 92492millionusingapproach1and92 492 million using approach 1 and 73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was 95004millionusingapproach1and95 004 million using approach 1 and 75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion: For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially

    Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy

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    Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe

    Global variation in anastomosis and end colostomy formation following left-sided colorectal resection

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    Background End colostomy rates following colorectal resection vary across institutions in high-income settings, being influenced by patient, disease, surgeon and system factors. This study aimed to assess global variation in end colostomy rates after left-sided colorectal resection. Methods This study comprised an analysis of GlobalSurg-1 and -2 international, prospective, observational cohort studies (2014, 2016), including consecutive adult patients undergoing elective or emergency left-sided colorectal resection within discrete 2-week windows. Countries were grouped into high-, middle- and low-income tertiles according to the United Nations Human Development Index (HDI). Factors associated with colostomy formation versus primary anastomosis were explored using a multilevel, multivariable logistic regression model. Results In total, 1635 patients from 242 hospitals in 57 countries undergoing left-sided colorectal resection were included: 113 (6·9 per cent) from low-HDI, 254 (15·5 per cent) from middle-HDI and 1268 (77·6 per cent) from high-HDI countries. There was a higher proportion of patients with perforated disease (57·5, 40·9 and 35·4 per cent; P < 0·001) and subsequent use of end colostomy (52·2, 24·8 and 18·9 per cent; P < 0·001) in low- compared with middle- and high-HDI settings. The association with colostomy use in low-HDI settings persisted (odds ratio (OR) 3·20, 95 per cent c.i. 1·35 to 7·57; P = 0·008) after risk adjustment for malignant disease (OR 2·34, 1·65 to 3·32; P < 0·001), emergency surgery (OR 4·08, 2·73 to 6·10; P < 0·001), time to operation at least 48 h (OR 1·99, 1·28 to 3·09; P = 0·002) and disease perforation (OR 4·00, 2·81 to 5·69; P < 0·001). Conclusion Global differences existed in the proportion of patients receiving end stomas after left-sided colorectal resection based on income, which went beyond case mix alone

    Apoptotic effect of crude scorpion venom on head and neck squamous cell carcinoma cell line versus normal human epithelial cell line: In-vitro study

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    Aim: The aim of this study was to investigate and compare the apoptotic effect of Leiurus quinquestriatus (LQ) scorpion venom on oral squamous cell carcinoma (OSCC) and normal human epithelial cell lines, in an attempt to introduce a novel selective therapeutic modality for OSCC. Methodology: we explored the effect of LQ scorpion venom on OSCC cell line (HNO-97) compared to normal oral epithelial (OEC) cell line. The cell viability by MTT assay and the expression of PUMA by ELISA were analyzed. Cell cycle analysis was studied for both groups using flow cytometry. Finally, we compared the expression of ROS by ELISA. Results LQ scorpion venom showed selective cytotoxic and apoptotic effect on OSCC cells. In comparison to normal cells, significant dose dependent cell viability reduction, cell cycle arrest and increased expression of apoptotic marker PUMA as well as ROS were observed in cancer cell group in comparison to the control group. Conclusions:&nbsp; LQ crude venom exerts a strong cytotoxic effect against OSCC with minimal effect on normal epithelial cells, thus, providing a selective, effective and less toxic possible chemotherapeutic agent for such a malignancy

    Unveiling Antimicrobial and Antioxidant Compositional Differences between Dukkah and Za&rsquo;atar via SPME-GCMS and HPLC-DAD

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    Interest in plant-based diets has been on the rise in recent years owing to the potential health benefits of their individual components and the notion that plant-based diets might reduce the incidence of several diseases. Egyptian dukkah and Syrian za&rsquo;atar are two of the most historic and famous Middle Eastern herbal blends used for their anti-inflammatory, hypolipidemic, and antidiabetic effects. Headspace SPME-GCMS and HPLC-DAD were adopted for characterizing the aroma profile and phenolic compounds of both herbal blends, respectively. Further, vapor-phase minimum inhibitory concentration was employed for assessing each blend&rsquo;s antibacterial potential, while their antioxidant potential was estimated via in vitro antioxidant assays. SPME headspace analysis indicated the abundance of ethers and monoterpene hydrocarbons, while HPLC revealed the presence of several phenolics including rosmarinic acid, ferulic acid, and rutin. Biological investigations affirmed that vapor-phase of the tested blends exhibited antibacterial activities against Gram-positive and Gram-negative pathogens, while the antioxidant potential of the blends was investigated and expressed as Trolox (125.15 &plusmn; 5.92 to 337.26 &plusmn; 13.84 &mu;M T eq/mg) and EDTA (18.08 &plusmn; 1.62 to 51.69 41 &plusmn; 5.33 &mu;M EDTA eq/mg) equivalent. The presented study offers the first insight into the chemical profile and biological activities of both dukkah and za&rsquo;atar

    Phenotypical changes of hematopoietic stem and progenitor cells in COVID-19 patients: Correlation with disease status

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    Hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) play a crucial role in the context of viral infections and their associated diseases. The link between HSCs and HPCs and disease status in COVID-19 patients is largely unknown. This study aimed to monitor the kinetics and contributions of HSCs and HPCs in severe and non-severe COVID-19 patients and to evaluate their diagnostic performance in differentiating between healthy and COVID-19 patients as well as severe and non-severe cases. Peripheral blood (PB) samples were collected from 48 COVID-19 patients, 16 recovered, and 27 healthy controls and subjected to deep flow cytometric analysis to determine HSCs and progenitor cells. Their diagnostic value and correlation with C-reactive protein (CRP), D-dimer, and ferritin levels were determined. The percentages of HSCs and common myeloid progenitors (CMPs) declined significantly, while the percentage of multipotent progenitors (MPPs) increased significantly in COVID-19 patients. There were no significant differences in the percentages of megakaryocyte-erythroid progenitors (MEPs) and granulocyte-macrophage progenitors (GMPs) between all groups. Severe COVID-19 patients had a significantly low percentage of HSCs, CMPs, and GMPs compared to non-severe cases. Contrarily, the levels of CRP, D-dimer, and ferritin increased significantly in severe COVID-19 patients. MPPs and CMPs showed excellent diagnostic performance in distinguishing COVID-19 patients from healthy controls and severe from non-severe COVID-19 patients, respectively. Collectively, our study indicated that hematopoietic stem and progenitor cells are significantly altered by COVID-19 and could be used as therapeutic targets and diagnostic biomarkers for severe COVID-19
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