369 research outputs found

    The Role of Acid Sites in the Catalytic Performance of Tungsten Oxide during the Dehydration of Isopropyl and Methyl Alcohols

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    Abstract WO 3 catalyst was prepared by thermal decomposition of ammonium metatungstate (AMT) in a static air atmosphere for 3h at 450, 550, 650 and 750 o C. The techniques employed for characterization of the catalyst were TG, DTA, XRD, FTIR, N 2 -sorption measurements. The surface acidity of the catalyst was investigated by adsorption of pyridine and 2, 6-dimethyl pyridine. The catalytic properties of the catalyst were carried out for the dehydration of isopropyl and methyl alcohols. The results revealed that WO 3 is more active toward isopropanol dehydration than methanol dehydration. Also reflect that the reaction mechanism and the yield of propene and dimethyl ether produced from dehydration of isopropyl and methyl alcohols are controlled by the strength of acid sites

    Productive Cross-Talk with the Microenvironment: A Critical Step in Ovarian Cancer Metastasis

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    Most ovarian cancer patients present with disseminated disease at the time of their diagnosis, which is one of the main reasons for their poor prognosis. Metastasis is a multi-step process and a clear understanding of the mechanism of regulation of these steps remains elusive. Productive reciprocal interactions between the metastasizing ovarian cancer cells and the microenvironment of the metastatic site or the tumor microenvironment play an important role in the successful establishment of metastasis. Much progress has been made in the recent past in our understanding of such interactions and the role of the cellular and acellular components of the microenvironment in establishing the metastatic tumors. This review will outline the role of the microenvironmental components of the ovarian cancer metastatic niche and their role in helping establish the metastatic tumors. Special emphasis will be given to the mesothelial cells, which are the first cells encountered by the cancer cells at the site of metastasis

    Role of interleukin-6 in diagnosis of pleural effusion

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    AbstractObjectivesTo determine the level of interleukin-6 (IL-6) in both serum and pleural fluid in order to evaluate the diagnostic utility of IL-6 in differentiation between different types of pleural effusion.BackgroundPleural effusion is a relatively common clinical condition. It is often diagnostic dilemma for the physician. Interleukin-6 (IL-6) has multiple functions on various cells and tissues. It is often used as a marker for systemic activation of pro-inflammatory cytokines.MethodsThis study was conducted on 40 patients of pleural effusion, they were selected from Al-Mahalla Chest Hospital in the period between October 2012 and May 2013. All patients were subjected to detailed clinical history, thorough clinical examination, plain chest-X-ray (postero-anterior and lateral views), blood sample for: Complete blood picture (CBC), erythrocyte sedimentation rate (ESR), liver functions, renal functions and serum and pleural fluid (LDH, protein and IL-6) by ELISA.ResultsSerum and effusion IL-6 could differentiate between exudate transudate as it increased in exudate than transudate. In the present study there was higher concentration of IL-6 in the serum and pleural effusion of parapneumonic effusion than malignant and tuberculous exudative pleural effusion and higher concentration in malignant than tuberculous effusion.ConclusionEffusion IL-6 could be used to differentiate between exudate and transudate and serum IL-6 could be used as an alternative non invasive method for differentiation between exudates and transudate as there was a significant positive correlation between serum IL-6 and effusion IL-6

    MHD natural convection in an inclined cavity filled with a fluid saturated porous medium with heat source in the solid phase

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    A numerical investigation of unsteady magnetohydrodynamic free convection in an inclined square cavity filled with a fluid-saturated porous medium and with internal heat generation has been performed. A uniform magnetic field inclined with the same angle of the inclination of the cavity is applied. The governing equations are formulated and solved by a direct explicit finite-difference method subject to appropriate initial and boundary conditions. Two cases were considered, the first case when all the cavity walls are cooled and the second case when the cavity vertical walls are kept adiabatic. A parametric study illustrating the influence of the Hartmann number, Rayliegh number, the inclination angle of the cavity and the dimensionless time parameter on the flow and heat transfer characteristics such as the streamlines, isotherms and the average Nusselt number is performed. The velocity components at mid section of the cavity as well as the temperature profiles are reported graphically. The values of average Nusselt number for various parametric conditions are presented in tabular form

    Clinical characteristics of depression among adolescent females: a cross-sectional study

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    <p>Abstract</p> <p>Background</p> <p>Adolescents rarely seek psychiatric help; they even hesitate to disclose their feelings to their parents. However; the adolescents especially the females experience depressive symptoms more frequently than general population. Do they experience classic depressive symptoms? Are there symptoms specific to this subpopulation?</p> <p>Aim of the study</p> <p>Through this study, the authors aimed to estimate the prevalence of depressive disorders in Egyptian adolescent female students. They also expected a characteristic profile of symptoms for the adolescent females. However available literature provides no guidance in the description of this profile of symptoms.</p> <p>Methods</p> <p>A number of 602 adolescent females were interviewed, and subjected to General Health Questionnaire (GHQ); Children Depression Inventory (CDI), Structured Clinical Interview for DSM-IV Axis-I Disorders (SCID-I), then Hamilton Rating Scale for Depression (Ham-D). Results were analyzed by the use of SPSS-15.</p> <p>Results</p> <p>The study revealed the prevalence of depression in the sample of the study to be 15.3% (measured by CDI), and 13.3% (measured by SCID-I). Fatigue was the most common presenting depressive symptom (81.3%), in addition to other emotional, cognitive and physiological symptoms. Suicidal ideations were the most common suicidal symptoms in depressed adolescent females (20%), with 2.5% serious suicidal attempts.</p> <p>Conclusions</p> <p>The somatic symptoms were by far the most common presenting symptom for female adolescents suffering from depressive disorders. Depressive phenomena including unexplained fatigue, decreased energy, psychomotor changes, lack of concentration, weight changes and suicidal ideations may be the presenting complaints instead of the classic sad mood.</p

    Extracorporeal Shock Wave Therapy Versus Ultrasonic Therapy on Functional Abilities in Children with Tennis Elbow a Randomized Controlled Trial

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    Abstract Background and Purpose: Extracorporeal shock-wave therapy (ESWT) is low-to medium-energy type of shockwave therapy. The purpose of the study was to compare the effect of extracorporeal shock wave therapy versus ultrasonic therapy in controlling the elbow pain, muscles weakness and limited range of motion due to tennis elbow in children

    A recent look for the implication and attitude of practicing female genital mutilation in upper Egypt: a cross sectional study

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    Background: Female genital mutilation (FGM) was defined as the partial or total removal of the female external genitalia for non-medical reasons The Demographic and Health Survey in Egypt in 2000 showed that 97% of married women included in the survey had experienced female genital mutilation.Methods: This is a cross sectional study to evaluate the current prevalence of FGM, current attitude of our society towards it after illegalization of it as a cross sectional survey of Upper Egypt. The most important point in this study is our evaluation of intention of these women whom exposed to FGM toward mutilation of their daughters or not and reasons for that. Statistical analysis was done using SPSS software version 21.Results: The study included 1175 women, from whom 89.1% were circumcised. Type 1 FGM was the most prevalent type practiced in about 58% of participants. Immediate complications occurred in 42.5% of women. Primary hemorrhage during circumcision was the most commonly reported immediate complication among 38.5% of them. Sexual problems were found in 40.5% of participants. Sixty-four women reported occurrence of hepatitis virus infection after the procedure. Moreover, 44 women were suffered from infertility and 72 women had an episode or chronic PID. Women who intend to circumcise their daughters are mostly those coming from rural areas (p=0.000) and housewives (p=0.000). Most of women (45.8%) who have the intent to circumcise their daughters claiming that it is religious based.Conclusions: The prevalence of FGM did not differ between urban and rural or between house wives and employee, lastly did not differ between different educational levels as most of them were encourage it thinking that it is of traditional, religious base and protect the girl from any abnormal sexual excitation. The women who intent not circumcise their daughters were from low educational level in its highest percentage and this was explained by occurrence of higher percentage of complications in spite of the highest percentage of operator was physician

    Regioselective formation of new 3-S-alkylated-1,2,4-triazole-quinolones

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    Regioselective synthesis of quinolone-1,2,4-triazoles was established starting from 4-hydroxyquinol-2-ones. The strategy started by the reaction of ethyl bromoacetate with 4-hydroxyquinoline to give the corresponding ethyl oxoquinolinyl acetates, which reacted with hydrazine hydrate to afford the hydrazide derivatives. Subsequently, hydrazides reacted with isothiocyanate derivatives to give the corresponding acyl thiosemicarbazides. Finally, subjecting the thiosemicarbazide derivatives with ethyl bromoacetate, the reaction underwent internal cyclization and alkylation processes. Alkylation occurred regioselectivity to the sulfur atom of the thione group and not to the amino group. Thus 3-S-1,2,4-triazole-quinolones were obtained in good yields. The structure of the obtained compounds was proved by different spectroscopic techniques together with elemental analysis and X-ray crystallography.Peer reviewe

    The Importance of Research on the Origin of SARS-CoV-2

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    The origin of the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) virus causing the COVID-19 pandemic has not yet been fully determined. Despite the consensus about the SARS-CoV-2 origin from bat CoV RaTG13, discrepancy to host tropism to other human Coronaviruses exist. SARS-CoV-2 also possesses some differences in its S protein receptor-binding domain, glycan-binding N-terminal domain and the surface of the sialic acid-binding domain. Despite similarities based on cryo-EM and biochemical studies, the SARS-CoV-2 shows higher stability and binding affinity to the ACE2 receptor. The SARS-CoV-2 does not appear to present a mutational “hot spot” as only the D614G mutation has been identified from clinical isolates. As laboratory manipulation is highly unlikely for the origin of SARS-CoV-2, the current possibilities comprise either natural selection in animal host before zoonotic transfer or natural selection in humans following zoonotic transfer. In the former case, despite SARS-CoV-2 and bat RaTG13 showing 96% identity some pangolin Coronaviruses exhibit very high similarity to particularly the receptor-binding domain of SARS-CoV-2. In the latter case, it can be hypothesized that the SARS-CoV-2 genome has adapted during human-to-human transmission and based on available data, the isolated SARS-CoV-2 genomes derive from a common origin. Before the origin of SARS-CoV-2 can be confirmed additional research is required
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