An investigation of the heat transfer by conduction and radiation between hot glass and tool moulding

This research work investigates heat transfer through the contact line between a glass mould and plunger in a press forming process. Models are formed and compared with experimental measurements to enable clarification of the glass properties that should be used in the optimisation process and have been suggested in previous research works. Two cases of heat transfer are considered in the models firstly the case of both conductive and radiative are present and then the case of radiative (reheat). The models developed during the study are based on one-dimensional heat transfer. The model is based on the period of the formation process starting from the point at which the molten glass is brought into contact with a mould until the time at which the formed glass is inverted. The models are concerned with the changes in temperature profile during this period at both the centre and the surface of the glass depending on the mode of heat transfer considered, the properties of the glass, and the properties of the tooling. The properties of the glass considered in the models include the absorption coefficient, refractive index, heat transfer coefficient, internal and external emissivity, specific heat and conductivity. In the radiation case the modelling results show the internal emissivity has a little effect on the surface temperature while the external emissivity has an effect temperature fall. Modelling of changes in glass thickness and glass absorption coefficient during the reheat stage of the process has been carried out based on white and green glass. Validation of these models has been accomplished by performing experimental work

The Role of Global Economic Growth in Pakistani Agri-Food Exports

This analysis uses least squares and Heckman maximum likelihood estimation procedures with fixed effects to explore the role of economic growth in 36 developed and developing economies—categorised as low-, lower-middle-, upper-middle-, and high-income—in explaining their agri-food import of 29 products from Pakistan during 1990 to 2000. We reject the hypothesis that the economic growth of these economies does not influence Pakistani agri-food product exports. However, the estimated income elasticities are statistically elastic only for lower-middle income countries, suggesting that their expenditure on Pakistani agri-food exports will increase disproportionately as their economies grow. Hence, lower-middle-income countries provide good export opportunities for Pakistan’s agri-food products. JEL Classifications: F14, Q17 Keywords: Economic Growth, Agri-food Trade, Income Elasticities, Developing Countrie

Urinary angiotensin-converting enzyme 2 and metabolomics in COVID-19-mediated kidney injury

COVID-19; Angiotensin-converting enzyme 2; MetabolomicsCOVID-19; Enzim convertidor d'angiotensina 2; MetabolòmicaCOVID-19; Enzima convertidora de angiotensina 2; MetabolómicaBackground Angiotensin-converting enzyme 2 (ACE2), the receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is highly expressed in the kidneys. Beyond serving as a crucial endogenous regulator of the renin–angiotensin system, ACE2 also possess a unique function to facilitate amino acid absorption. Our observational study sought to explore the relationship between urine ACE2 (uACE2) and renal outcomes in coronavirus disease 2019 (COVID-19). Methods In a cohort of 104 patients with COVID-19 without acute kidney injury (AKI), 43 patients with COVID-19-mediated AKI and 36 non-COVID-19 controls, we measured uACE2, urine tumour necrosis factor receptors I and II (uTNF-RI and uTNF-RII) and neutrophil gelatinase-associated lipocalin (uNGAL). We also assessed ACE2 staining in autopsy kidney samples and generated a propensity score–matched subgroup of patients to perform a targeted urine metabolomic study to describe the characteristic signature of COVID-19. Results uACE2 is increased in patients with COVID-19 and further increased in those that developed AKI. After adjusting uACE2 levels for age, sex and previous comorbidities, increased uACE2 was independently associated with a >3-fold higher risk of developing AKI [odds ratio 3.05 (95% confidence interval 1.23‒7.58), P = .017]. Increased uACE2 corresponded to a tubular loss of ACE2 in kidney sections and strongly correlated with uTNF-RI and uTNF-RII. Urine quantitative metabolome analysis revealed an increased excretion of essential amino acids in patients with COVID-19, including leucine, isoleucine, tryptophan and phenylalanine. Additionally, a strong correlation was observed between urine amino acids and uACE2. Conclusions Elevated uACE2 is related to AKI in patients with COVID-19. The loss of tubular ACE2 during SARS-CoV-2 infection demonstrates a potential link between aminoaciduria and proximal tubular injury.This work was supported by the Heart and Stroke Foundation (grant 855632 to G.Y.O.) and the Canada Foundation for Innovation (grant 35456). A.V. is a current recipient of a Fundacion Alfonso Martin Escudero–2020 Research Grant

Male fertility and the COVID-19 pandemic: Systematic review of the literature

Purpose: Since its discovery in December 2019, the novel coronavirus SARS-CoV-2 has spread globally, causing the current COVID-19 (coronavirus disease-19) pandemic. As there is an increase of infections in the male population, concerns have emerged about the potential impact of COVID-19 on male reproductive organs and male fertility. Therefore, this study systematically investigates the current evidence of SARS-CoV-2 impact on male reproduction and pregnancy outcomes, discussing them in light of the evidence published on other coronaviruses. Materials and Methods: Literature search was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 24 original articles were included for the analysis, investigating the effects of the infection on semen parameters, male reproductive hormones, and pregnancy outcomes

Revenue Determinants for Abu-Dhabi Fishermen and Assessment of Input Allocative Efficiency

This study examined the fishing industry in Abu Dhabi, the main fish-producing Emirate in the UAE, from the fishermen’s point of view. Marginal analysis was used to identify the most prominent fishing-revenue determinants along with assessing the allocative (price) efficiency of inputs used. A log-log total value product (TVP) function was estimated for a representative cross-section random sample of 131 Abu-Dhabi fishermen. This revealed that (1) labor, fishing effort, boat capacity, boat boarding expenses, and expenditures on oil and lubricants are the five main determinants of total revenue for the individual fishermen in Abu Dhabi; (2) boat-purchase price constituted a huge investment cost to fishermen distributed over the lifetime of the boat; although only one-third of fishermen acquire loans for this purpose; (3) the only type of records fishermen keep were those pertinent to monthly revenues; and (4) price efficiency is found not to be achieved for any of the five prominent inputs that have great impact on total fishermen’s revenues, as three inputs were found to be under-utilized in varying degrees, whereas two were found to be significantly over-utilized

Consumers’ Attitudes and Perceptions of Food Safety in the United Arab Emirates

This study analyzes consumers’ attitudes and perceptions of food safety in the United Arab Emirates (UAE). The study hypothesized that different ethnic groups perceive food safety differently for a number of reasons. A cross-section sample representing the country’s four ethnic groups was analyzed. A probit model was used to analyze factors affecting consumers’ perception and attitude toward major food safety concerns and practices. The results show that the most common food safety practice was reading expiration dates, food poisoning was the most frequent food safety concern, the family doctor was the most trusted source of information, and the householder himself was the most responsible entity regarding food safety. The respondents’ education levels and their ethnicity were the main determinants of their attitudes toward major food-safety concerns. The results indicated that it would be more effective for food-safety awareness campaigns to be disseminated through different sources of information targeting different ethnic groups

Public Acceptance of Wastewater Reuse: New Evidence from Factor and Regression Analyses

The present study attempts to unravel the determinants of public acceptance of Treated Wastewater (TWW) reuse in the United Arab Emirates. A representative sample (1426) of Al-Ain city residents, were interviewed, using a structured questionnaire, on their knowledge and attitudes towards TWW reuse, and other demographic characteristics. Descriptive analysis shows high public acceptance for applications with low contact and lower acceptance for those involving direct or indirect consumption of TWW, and/or skin contact. The Principal Component Analysis (PCA) of acceptance responses identified (Kaiser–Mayer–Olkin test = 0.942; p-value < 0.001 for Bartlett’s test) five factors/categories of applications that differ in level and type of contact. The five groups of applications are Direct consumption, Indirect Consumption, Non-food Agricultural, Industrial, and Skin Contact. ANOVA analysis (p < 0.0001) and Spearman’s Rho test validated earlier findings. Another PCA of respondents’ reasons for hesitation towards TWW delivers two factors, attitude toward contamination risk and psychological “yuck” factors. Regression analyses show that both factors are influenced by knowledge and sources of information, and the former is affected by demographic characteristics. PCA and regression analyses provide a robust methodological framework for the study TWW reuse acceptance, and highlight the importance of communication in improving its social sustainability