21 research outputs found

    Studying The Role Of Phase Change Materials In Improving The Thermal Performance Efficiency Of Adaptive Building Envelopes

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    In the context of unsustainable approaches, buildings are increasingly dependent on mechanical systems to ensure quality requirements of thermal indoor environment, which causes the need for more energy as well as rising the associated greenhouse gas emissions rates. This requires increased awareness towards energy conservation and reduction of energy consumption in conjunction with enhancing buildings sustainability. In this regard, we find that the building envelope plays a crucial role in reducing energy consumption; as well as its role in raising the performance of buildings as the regulating mediator in the reciprocal relationship between the internal and external environment, especially when applying appropriate technical solutions and energy-saving materials within the structure of the envelope, which enhances the concept of passive adaptation to the simultaneous environmental changes. So, Improving the efficiency of energy performance during the operational phases of the building envelope is a vigorous area of research; Organizations and responsible authorities are always seeking to come up with advanced technologies based on renewable energy sources in order to reduce buildings’ dependence on fossil fuels and provide cooling and/or heating energy requirements, as well as improve indoor thermal comfort in a more sustainable and cost-effective manner.In this regard, Thermal Energy Storage Systems (TES) are discussed as one of the most effective advanced technologies in managing the thermal performance of the building envelope with a particular focus on studying the role of Phase Change Materials (PCMs) in raising the efficiency of the building's thermal performance. This study sheds light on the importance of applying phase-changing materials in the building envelope and its role in activating the principle of thermal adaptation to daily fluctuations. by discussing the nature of that category of materials, their types, and their distinctive properties in addition to studying its main working principle, then studying criteria for choosing the most appropriate. focusing on current studies and future scenarios for these materials to monitor their thermal behavior and examine their role in raising the efficiency of the building envelopes performance. The main results indicated that the phase change materials have a significant effect on reducing the cooling/heating load, saving energy and gaining thermal comfort

    Biomimetics As An Analogical Reasoning Ideology In Architectural & Interior Design

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    Biomimetics approaches involve finding solutions to design problems by mimicking the functions and/or processes of biological systems, by applying an analog reasoning strategy from ecosystems to technology in a way that addresses the challenges of architectural and interior design in a more sustainable way. This is due to it is a sustainable creative thinking ideology producing more inspiring solutions that are most restorative and regenerative ecosystems ... The study assumes that mimicking the processes and functions of ecosystems enhances the structural efficiency of the building and stimulates the creation of innovative materials, urging synthesis of innovative materials, as well as providing more sustainable technologies in waste and water management, In addition to reducing energy consumption by adopting mechanisms that passively provide thermal comfort, in conjunction with maximizing the principle of generating energy from renewable sources ... This study was presented to verify the ability of Biomimetics as an analogue ideology in raising the efficiency of the operational building performance from a structural efficiency perspective, and reduce energy consumption.Therefore, this study included evaluating the efficiency of applying that intellectual methodology based on analog transfer of functions and processes of biological systems in providing the building environment with the characteristics of innovation and sustainability, as well as studying the ability of that intellectual methodology to raise the structural efficiency of the building, and discuss the impact of its activation on the synthesis of advanced materials in conjunction with a study of its ability to improve water and waste management, in addition to enhancing the thermoregulation of the indoor environment within a sustainable environmental framework; corresponding to the operational performance of the ecosystem enhanced by the regenerative design in architecture that promotes the repair and renewal of surrounding ecosystems

    Natural history, with clinical, biochemical and molecular characterization, of classical homocystinuria in the Qatari population

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    Classical homocystinuria (HCU) is the most common inborn error of metabolism in Qatar, with an incidence of 1:1800, and is caused by the Qatari founder p.R336C mutation in the CBS gene. This study describes the natural history and clinical manifestations of HCU in the Qatari population. A single center study was performed between 2016 and 2017 in 126 Qatari patients, from 82 families. Detailed clinical and biochemical data were collected and Stanford-Binet intelligence, quality of life and adherence to treatment assessments were conducted prospectively. Patients were assigned to one of three groups, according to mode of diagnosis: 1) Late Diagnosis Group (LDG), 2) Family Screening Group (FSG), and 3) Newborn Screening Group (NSG). Of the 126 patients, 69 (55%) were in the LDG, 44 (35%) in the NSG, and 13 (10%) in the FSG. The leading factors for diagnosis in the LDG were ocular manifestations (49%), neurological manifestations (45%), thromboembolic events (4%), and hyperactivity and behavioral changes (1%). Both FSG and NSG groups were asymptomatic at time of diagnosis. NSG had significantly higher IQ, QoL, and adherence values compared with the LDG. The LDG and FSG had significantly higher Met levels than the NSG. The LDG also had significantly higher tHcy levels than the NSG and FSG. Regression analysis confirmed these results even when adjusting for age at diagnosis, current age or adherence. These findings increase understanding of the natural history of HCU and highlight the importance of early diagnosis and treatment. This article is protected by copyright. All rights reserved.Qatar National Research Fund , Grant/Award Number: 7‐355‐3‐08

    Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

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    In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

    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

    Prediction and Optimization of Drilling Parameters in Drilling of AISI 304 and AISI 2205 Steels with PVD Monolayer and Multilayer Coated Drills

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    Due to their high ductility, high durability, and excellent corrosion resistance, stainless steels are attractive materials for a variety of applications. However, high work hardening, low thermal conductivity, and high built-up edge (BUE) formation make these materials difficult to machine. Rapid tool wear and high cutting forces are the common problems encountered while machining these materials. In the present work, the application of Taguchi optimization methodology has been used to optimize the cutting parameters of the drilling process for machining two stainless steels: austenitic AISI 304 and duplex AISI 2205 under dry conditions. The machining parameters which were chosen to be evaluated in this study are the tool material, cutting speed, and feed rate, while, the response factors to be measured are the tool life (T), cutting force (Fc), and specific cutting energy (ks). Additionally, empirical models were created for predicting the T, Fc and ks using linear regression analysis. The results of this study show that AISI 2205 stainless steel has a shorter tool life, a higher cutting force, and a higher specific cutting energy than AISI 304 stainless steel. In addition, the Taguchi method determined that A3B1C1 and A3B3C1 (A3 = TiN-coated twist drill, B1 = 13 m/min, B3 = 34 m/min, C1 = 0.12 mm/rev) are the optimized combination of levels for the best tool life and the lowest cutting force, respectively. Meanwhile, the optimized combination of levels for all three control factors from the analysis, which provides the lowest specific cutting energy, was found to be A3B1C3 (A3 = TiN-coated twist drill, B1 = 13 m/min, C3 = 0.32 mm/rev) for both stainless steels

    Scrutinizing the Feasibility of Nonionic Surfactants to Form Isotropic Bicelles of Curcumin: a Potential Antiviral Candidate Against COVID-19

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    Investigating bicelles as an oral drug delivery system and exploiting their structural benefits can pave the way to formulate hydrophobic drugs and potentiate their activity. Herein, the ability of non-ionic surfactants (labraso

    CTNNB1 polymorphism (rs121913407) in circulating tumor DNA (ctDNA) in Egyptian hepatocellular carcinoma patients

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    Abstract Background Hepatocellular carcinoma (HCC) represents the sixth most common cancer worldwide and the fourth in Egypt. Persistent inflammation and specific somatic mutations in driving genes play a major role in the development of HCC. One of these somatic mutations is CTNNB1 mutations with subsequent activation of ÎČ-catenin in HCC, associated with a risk of malignant transformation. In this study, we investigate the clinical utility of peripheral blood circulating tumor DNA (ctDNA) CTNNB1 (rs121913407) in HCC patients compared to pathological chronic hepatitis C virus (HCV) patients and healthy controls. Methods Our study is a case-control study at the Ain Shams Centre for Organ Transplantation, Ain Shams University Hospitals, enrolling twenty-eight adult HCC patients (twelve early HCC patients and sixteen advanced HCC patients), ten patients with chronic hepatitis C as a disease control group, and ten healthy controls. We collected plasma and stored at −80 °C. We detected mutations in the gene locus CTNNB1 rs121913407 by real-time PCR. Results All of our studied cases (early and advanced HCC) in addition to HCV and healthy control groups were CTNNB1 wild (TT) genotype. There was statistical significant difference between early and late cases of HCC as regards AFP and AST. Conclusions None of our recruited subjects showed CTNNB1 rs121913407 gene mutation. Further studies on larger number of patients are needed to clarify and confirm the clinical utility of CTNNB1 single-nucleotide polymorphism in the pathogenesis of HCC related to HCV in Egyptian population

    Common childhood vaccines do not elicit a cross-reactive antibody response against SARS-CoV-2.

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    Anecdotal evidence showed a negative correlation between Bacille Calmette-Guérin (BCG) vaccination and incidence of COVID-19. Incidence of the disease in children is much lower than in adults. It is hypothesized that BCG and other childhood vaccinations may provide some protection against SARS-CoV-2 infection through trained or adaptive immune responses. Here, we tested whether BCG, Pneumococcal, Rotavirus, Diphtheria, Tetanus, Pertussis, Hepatitis B, Haemophilus influenzae, Hepatitis B, Meningococcal, Measles, Mumps, and Rubella vaccines provide cross-reactive neutralizing antibodies against SARS-CoV-2 in BALB/c mice. Results indicated that none of these vaccines provided antibodies capable of neutralizing SARS-CoV-2 up to seven weeks post vaccination. We conclude that if such vaccines have any role in COVID-19 immunity, this role is not antibody-mediated
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