47 research outputs found

    Coatings in Photovoltaic Solar Energy Worldwide Research

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    This paper describes the characteristics of contributions that were made by researchers worldwide in the field of Solar Coating in the period 1957–2019. Scopus is used as a database and the results are processed while using bibliometric and analytical techniques. All of the documents registered in Scopus, a total of 6440 documents, have been analyzed and distributed according to thematic subcategories. Publications are analyzed from the type of publication, field of use, language, subcategory, type of newspaper, and the frequency of the keyword perspectives. English (96.8%) is the language that is most used for publications, followed by Chinese (2.6%), and the rest of the languages have a less than < 1% representation. Publications are studied by authors, affiliations, countries of origin of the authors, and H-index, which it stands out that the authors of China contribute with 3345 researchers, closely followed by the United States with 2634 and Germany with 1156. The Asian continent contributes the most, with 65% of the top 20 affiliations, and Taiwan having the most authors publishing in this subject, closely followed by Switzerland. It can be stated that research in this area is still evolving with a great international scientific contribution in improving the efficiency of solar cells

    Subclinical hypothyroidism among Egyptian children with systemic lupus erythematosus

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    Background: Thyroid autoimmune diseases have been associated with systemic lupus erythematosus (SLE). Both hypothyroidism and hyperthyroidism are seen, but hypothyroidism is the most common abnormality. Subclinical hypothyroidism (SCH) has been reported among adult lupus patients. SCH is not without risk as it might contribute to a proatherogenic state. Objectives: This study was aimed to assess the frequency of SCH in a group of Egyptian children with SLE and its effects on the serum lipids. Methods: Forty patients with pediatric SLE who regularly follow up at our center were enrolled in this study. They were subjected to routine laboratory investigations of SLE and measurement of serum lipids (serum triglycerides, cholesterol, LDL and HDL) as well as free thyroxine (T4), thyroid stimulating hormone (TSH) and anti-thyroperoxidase antibody (anti-TPO-ab) titre. SLE activity was assessed using the systemic lupus erythematosus disease activity index (SLEDAI). Results: Six patients (15%) were found to have SCH while the remaining 34 patients (85%) had normal thyroid function. Anti-TPO-abs were positive in 4 out of the 6 (66.6 %) SLE patients with SCH and in 20 out of the 34 (58.8%) SLE patients with normal thyroid function. In SLE patients with SCH, TSH correlated positively yet insignificantly with anti-TPO-ab titre and the duration of SLE (p = 0.17, p = 0.12, respectively). There were no statistically significant correlations between the serum lipids of SLE patients with SCH and their thyroid function or anti-TPO-ab titre. Conclusion: SCH is not uncommon among children with SLE. This SCH does not seem to affect serum lipids. However, further longitudinal studies on wider scales are needed to assess the long term effects of SCH in those patients.Keywords: SLE, anti-thyroperoxidase antibodies, subclinical hypothyroidismEgypt J Pediatr Allergy Immunol 2011;9(2):87-9

    La formación educativa de la mujer en el Líbano: lecciones para Oriente Medio

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    Resumen basado en el de la publicaciónSe analiza el sistema educativo en el Líbano, sus componentes y el proceso exitoso de la integración de la mujer en los últimos 15 años. Se analiza el diseño del sistema educativo desde la fundación de las instituciones educativas libanesas, empezando con las escuelas extranjeras para llegar a la expansión de las escuelas públicas donde se necesita mejorar la educación pública de calidad. Respecto al analfabetismo, los datos son prometedores comparados con los países de su entorno. Se revela que la presencia de la mujer está siendo más relevante en el sistema educativo a partir de las primeras etapas y se vuelve más dominante poniéndose de manifiesto que la mejor manera de ofrecer un futuro a las mujeres de oriente medio y las del Líbano en particular, es a través de la mejora del puente educativo y cultural entre el Líbano y el resto del mundo, y para ello la implantación del bilingüismo juega una papel clave.ES

    Comprehensive risk assessment of heavy metals in surface sediments along the Egyptian Red Sea coast

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    AbstractThe contamination of heavy metals (Fe, Zn, Mn, Cu, Ni, Pb, Cd, Co, Cr, and Hg) in 16 surface sediment samples collected from the Suez Gulf, Aqaba Gulf and the Red Sea Proper was studied to evaluate their distribution and potential ecological risk. The concentrations of the studied metals decreased in the order of Fe>Mn>Zn>Cr>Ni>Co>Pb>Cu>Cd>Hg (3490.2, 115.77, 28.66, 18.47, 11.40, 9.70, 3.26, 1.94, 6.10, 0.02μg/g dry weight). Based on the effect-range classification (ERL–ERM, TEL–PEL, LEL–SEL), the studied heavy metals did not pose any environmental risks for all investigated stations except Marsa Alam and El-Quseir stations, which may pose an environmental risk for Cr and Ni. The ecological risk assessment for metals in surface sediments was evaluated using the metal pollution index (MPI), geoaccumulation index (Igeo), and potential ecological risk index (ERI). Multivariate techniques including Pearson correlation, hierarchical cluster and principal components analysis were used to evaluate the metal sources

    Dielectric Spectroscopy in Biomaterials: Agrophysics

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    Being dependent on temperature and frequency, dielectric properties are related to various types of food. Predicting multiple physical characteristics of agri-food products has been the main objective of non-destructive assessment possibilities executed in many studies on horticultural products and food materials. This review manipulates the basic fundamentals of dielectric properties with their concepts and principles. The different factors affecting the behavior of dielectric properties have been dissected, and applications executed on different products seeking the characterization of a diversity of chemical and physical properties are all pointed out and referenced with their conclusions. Throughout the review, a detailed description of the various adopted measurement techniques and the mostly popular equipment are presented. This compiled review serves in coming out with an updated reference for the dielectric properties of spectroscopy that are applied in the agrophysics fiel

    Electronics and Its Worldwide Research

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    The contributions of researchers at a global level in the journal Electronics in the period 2012–2020 are analyzed. The objective of this work is to establish a global vision of the issues published in the Electronic magazine and their importance, advances and developments that have been particularly relevant for subsequent research. The magazine has 15 thematic sections and a general one, with the programming of 385 special issues for 2020–2021. Using the Scopus database and bibliometric techniques, 2310 documents are obtained and distributed in 14 thematic communities. The communities that contribute to the greatest number of works are Power Electronics (20.13%), Embedded Computer Systems (13.59%) and Internet of Things and Machine Learning Systems (8.11%). A study of the publications by authors, affiliations, countries as well as the H index was undertaken. The 7561 authors analyzed are distributed in 87 countries, with China being the country of the majority (2407 authors), followed by South Korea (763 authors). The H-index of most authors (75.89%) ranges from 0 to 9, where the authors with the highest H-Index are from the United States, Denmark, Italy and India. The main publication format is the article (92.16%) and the review (5.84%). The magazine publishes topics in continuous development that will be further investigated and published in the near future in fields as varied as the transport sector, energy systems, the development of new broadband semiconductors, new modulation and control techniques, and more

    Association of respiratory symptoms and lung function with occupation in the multinational Burden of Obstructive Lung Disease (BOLD) study

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    Background Chronic obstructive pulmonary disease has been associated with exposures in the workplace. We aimed to assess the association of respiratory symptoms and lung function with occupation in the Burden of Obstructive Lung Disease study. Methods We analysed cross-sectional data from 28 823 adults (≥40 years) in 34 countries. We considered 11 occupations and grouped them by likelihood of exposure to organic dusts, inorganic dusts and fumes. The association of chronic cough, chronic phlegm, wheeze, dyspnoea, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)/FVC with occupation was assessed, per study site, using multivariable regression. These estimates were then meta-analysed. Sensitivity analyses explored differences between sexes and gross national income. Results Overall, working in settings with potentially high exposure to dusts or fumes was associated with respiratory symptoms but not lung function differences. The most common occupation was farming. Compared to people not working in any of the 11 considered occupations, those who were farmers for ≥20 years were more likely to have chronic cough (OR 1.52, 95% CI 1.19–1.94), wheeze (OR 1.37, 95% CI 1.16–1.63) and dyspnoea (OR 1.83, 95% CI 1.53–2.20), but not lower FVC (β=0.02 L, 95% CI −0.02–0.06 L) or lower FEV1/FVC (β=0.04%, 95% CI −0.49–0.58%). Some findings differed by sex and gross national income. Conclusion At a population level, the occupational exposures considered in this study do not appear to be major determinants of differences in lung function, although they are associated with more respiratory symptoms. Because not all work settings were included in this study, respiratory surveillance should still be encouraged among high-risk dusty and fume job workers, especially in low- and middle-income countries.publishedVersio

    Cohort Profile: Burden of Obstructive Lung Disease (BOLD) study

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    The Burden of Obstructive Lung Disease (BOLD) study was established to assess the prevalence of chronic airflow obstruction, a key characteristic of chronic obstructive pulmonary disease, and its risk factors in adults (≥40 years) from general populations across the world. The baseline study was conducted between 2003 and 2016, in 41 sites across Africa, Asia, Europe, North America, the Caribbean and Oceania, and collected high-quality pre- and post-bronchodilator spirometry from 28 828 participants. The follow-up study was conducted between 2019 and 2021, in 18 sites across Africa, Asia, Europe and the Caribbean. At baseline, there were in these sites 12 502 participants with high-quality spirometry. A total of 6452 were followed up, with 5936 completing the study core questionnaire. Of these, 4044 also provided high-quality pre- and post-bronchodilator spirometry. On both occasions, the core questionnaire covered information on respiratory symptoms, doctor diagnoses, health care use, medication use and ealth status, as well as potential risk factors. Information on occupation, environmental exposures and diet was also collected

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century
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