TECHNO-ECONOMIC ANALYSIS OF USING PV CURTAIN WALLS IN HOT ARID ENVIRONMENTCASE STUDY; MIXED-USE BUILDING, JEDDAH, KSA

Nowadays the world no longer has a choice to reduce the dependency of non-renewable energy resources, especially in buildings. This type of energy like fossil fuel is responsible for global warming and the climate change phenomenon. The construction industry has to depend on renewable energy to improve environmental impacts while operating the buildings. The most promising technologies for buildings are photovoltaic panels system which converts solar radiation into electricity without harming the environment. PV system is not only used as top-roof panels but also it can play an important role in the exterior building cladding and in curtain wall system as well. Building-integrated PV (BIPV) system has two functions the first is used as a façade cladding and the second is power generation for building operation. This research studies the PV curtain wall as a BIPV system and explains why this system is better than the traditional curtain wall through its environmental performance and initial, and operation costs. Based on the analysed tabulated feasibility study considering energy savings outcome and system cost, PV curtain walls proved technical, environmental and economic viability. The paper’s case study in Jeddah-KSA provides a real example of how PV curtain wall application plays a fundamental role in achieving high energy performance standards as well as maximize the financial return of investment

Three Stage Cool Flame Droplet Burning Behavior of n-Alkane Droplets at Elevated Pressure Conditions: Hot, Warm and Cool Flame

Transient, isolated n-alkane droplet combustion is simulated at elevated pressure for helium-diluent substituted-air mixtures. We report the presence of unique quasi-steady, three-stage burning behavior of large sphero-symmetric n-alkane droplets at these elevated pressures and helium substituted ambient fractions. Upon initiation of reaction, hot-flame diffusive burning of large droplets is initiated that radiatively extinguishes to establish cool flame burning conditions in nitrogen/oxygen air at atmospheric and elevated pressures. However, at elevated pressure and moderate helium substitution for nitrogen ( X He > 20%), the initiated cool flame burning proceeds through two distinct, quasi-steady-state, cool flame burning conditions. The classical Hot flame ( 1500 K) radiatively extinguishes into a Warm flame burning mode at a moderate maximum reaction zone temperature ( 970 K), followed by a transition to a lower temperature ( 765 K), quasi-steady Cool flame burning condition. The reaction zone (flame) temperatures are associated with distinctly different yields in intermediate reaction products within the reaction zones and surrounding near-field, and the flame-standoff ratios characterizing each burning mode progressively decrease. The presence of all three stages first appears with helium substitution near 20%, and the duration of each stage is observed to be strongly dependent on helium substitutions level between 2060%. For helium substitution greater than 60%, the hot flame extinction is followed by only the lower temperature cool flame burning mode. In addition to the strong coupling between the diffusive loss of both energy and species and the slowly evolving degenerate branching in the low and negative temperature coefficient (NTC) kinetic regimes, the competition between the low-temperature chain branching and intermediate-temperature chain termination reactions control the Warm and Cool flame quasi-steady conditions and transitioning dynamics

Methylmercury varies more than one order of magnitude in commercial European rice

P.M. thanks the Royal Thai Government for funding and C.C.B. thanks the School of Natural and Computing Science and PS Analytical for funding.Peer reviewedPostprin

Phytochemical screening and biological activity studies of five South African indigenous medicinal plants

Different extracts and fractions of five selected indigenous South African medicinal plants, namely, Cissampelos capensis, Geranium incanum and three Gethyllis species, were subjected to phytochemical screening and testing for cytotoxicity using the brine shrimp lethality bioassay, and antimicrobial activity assays against nine microbes, which included three fungal species, three Gram negative and three Gram positive bacteria.The majority of the extracts tested positive for the presence of tannins, phenolics and flavonoids, while in selected cases, phytochemical tests suggested the presence of essential oils, glycosides or alkaloids. The methanol extract of Gethyllis gregoriana displayed the highest cytotoxicity levels. Generally, the highest levels of biological activity were shown to reside in the methanolic extracts, while hexane extracts revealed very low to zero activity. The total tertiary alkaloid (TTA) of C. capensis was mostly active against Bacillus subtilis, a Gram +ve bacteria. The trends observed for the cytotoxicity assay were in agreement with those observed for the antimicrobial assay

Common mental disorders in mothers of children attending out-patient malnutrition clinics in rural North-western Nigeria: a cross-sectional study.

BACKGROUND: Children with uncomplicated severe acute malnutrition are managed routinely within out-patient malnutrition treatment programs. These programs do not offer maternal mental health support services, despite maternal mental health playing a significant role in the nutritional status of children. Additionally, the burden of maternal Common Mental Disorders (CMDs) is poorly described among mothers of children attending these programs. This study thus determined the burden and risk factors for maternal CMDs among children attending out-patient malnutrition clinics in rural North-western Nigeria. METHODS: We conducted a cross-sectional study among 204 mothers of children with severe acute malnutrition who attending eight out-patient malnutrition clinics in Jigawa, North-western Nigeria. We used the World Health Organization Self-Reporting Questionnaire-20 (WHO SRQ-20) screening tool, a recognised and validated proxy measure for CMDs to identify mothers with CMDs. The prevalence of maternal CMDs was determined by identifying the proportion of mothers with SRQ scores of ≥8. Risk factors for CMD were determined using multivariable logistic regression. RESULTS: Maternal CMD prevalence in children attending these facilities was high at 40.7%. Non-receipt of oral polio vaccine (OPV) (AOR 6.23, 95%CI 1.85 to 20.92) increased the odds for CMD. While spousal age above 40 (AOR 0.95, 95%CI 0.90 to 0.99) and long years spent married (AOR 0.92, 95%CI 0.85 to 0.98) decreased the odds for CMD. CONCLUSIONS: Our findings indicate maternal CMD burden is high in out-patient malnutrition clinics in North-western Nigeria. Maternal mental health services would need to be integrated into the community management of acute malnutrition programs to provide more holistic care, and possibly improve long-term outcomes after discharge from these programs

Impact of the COVID-19 pandemic on the quality of medical products in Zimbabwe: a qualitative study based on key informant interviews with health system stakeholders

Objective To explore the impact of the Coronavirus disease 2019 (COVID-19) pandemic on the quality of medical products in Zimbabwe, including market risks for substandard and falsified products and impacts on quality assurance activities. Design Qualitative study based on in-depth key informant interviews. Setting Health system stakeholders across the medical product supply chain in Zimbabwe. Participants 36 key informants were interviewed between April and June 2021. Results We found that the COVID-19 pandemic disrupted quality assurance and regulatory activities of medical products in Zimbabwe, resulted in observations of poor-quality personal protective equipment (PPE) and other COVID-19-related products and led to increased risks to quality. Risks to quality due to COVID-19-related disruptions included increased layers of agents in the supply chain and an influx of non-traditional suppliers. COVID-19-related movement restrictions reduced access to health facilities and thus may have increased the usage of the informal market where smuggled and unregistered medical products are sold with less oversight by the regulator. Most reports of poor-quality medical products were for PPE, such as masks and infrared thermometers, used for the COVID-19 response. Besides these reports, many participants stated that the quality of essential medicines in the formal sector, not related to COVID-19, had largely been maintained during the pandemic due to the regulator’s stringent quality assurance process. Incentives for suppliers to maintain quality to retain large donor-funded contracts, and the need for local wholesalers and distributors to comply with quality-related aspects of distribution agreements with global manufacturers of brand-name medical products, mitigated threats to quality. Conclusions The COVID-19 pandemic presented opportunities and market risks for circulation of substandard and falsified medical products in Zimbabwe. There is a need for policymakers to invest in measures to safeguard the quality of medical products during emergencies and to build resiliency against future supply chain shocks

Laminin and Fibronectin Treatment Leads to Generation of Dendritic Cells with Superior Endocytic Capacity

Copyright: 2010 Garcı´a-Nieto et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: Sampling the microenvironment at sites of microbial exposure by dendritic cells ( DC) and their subsequent interaction with T cells in the paracortical area of lymph nodes are key events for initiating immune responses. Most of our knowledge of such events in human is based on in vitro studies performed in the absence of extracellular matrix (ECM) proteins. ECM in basement membranes and interstitial spaces of different tissues, including lymphoid organs, plays an important role in controlling specific cellular functions such as migration, intracellular signalling and differentiation. The aim of this study was, therefore, to investigate the impact of two abundant ECM components, fibronectin and laminin, on the phenotypical and functional properties of DC and how that might influence DC induced T-cell differentiation. Methodology/Principal Findings: Human monocyte derived DC were treated with laminin and fibronectin for up to 48 hours and their morphology and phenotype was analyzed using scanning electron microscopy, flow cytometry and real time PCR. The endocytic ability of DC was determined using flow cytometry. Furthermore, co-culture of DC and T cells were established and T cell proliferation and cytokine profile was measured using H(3)-thymidine incorporation and ELISA respectively. Finally, we assessed formation of DC-T cell conjugates using different cell trackers and flow cytometry. Our data show that in the presence of ECM, DC maintain a 'more immature' phenotype and express higher levels of key endocytic receptors, and as a result become significantly better endocytic cells, but still fully able to mature in response to stimulation as evidenced by their superior ability to induce antigen-specific T cell differentiation. Conclusion: These studies underline the importance of including ECM components in in vitro studies investigating DC biology and DC-T cell interaction. Within the context of antigen specific DC induced T cell proliferation, inclusion of ECM proteins could lead to development of more sensitive assays.Peer reviewedFinal Published versio

Modified Chitosan Hydrogels and Nano Hydrogels for Congo Red Removal from Aqueous System

In the present work, sulfonamide chitosan derivatives were prepared via the reaction of chitosan (Cs) with diphenyl ether – 4, 4`- disulfonylchloride (DPE) in absence and/or presence of glutaraldehyde (G) to form the hydrogel (DPE-I) and (DPE-II) respectively. The nanogels (DPE-III) and (DPE-IV) were prepared via ionotropic gelation method in presence of sodium tri polyphosphate (TPP) under the same reaction conditions. The hydrogels (DPE-I, DPE-II, DPE-III, and DPE- IV) were characterized by different tools as: Elemental analysis, Fourier Transform Infra-Red spectrometer (FT-IR), Proton Nuclear Magnetic Resonance (1HNMR), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM). The adsorption efficiency of the prepared hydrogels for removal of congo red dye (CR) from aqueous solution under different parameters such as (time, pH, and concentration) was evaluated. The adsorption capacity of CR by the prepared hydrogels increased with time, adsorbent dosage and the initial concentration of CR. The optimum adsorption capacity for CR dye by the prepared hydrogels was at pH 7. Hydrogels (DPE-III and DPE-IV) showed the highest efficiency for adsorption of (CR) dye