Optimization of process conditions to improve copper adsorption capacity of raw and treated Algerian bentonite: Characterization, kinetics and equilibrium study

249-261Raw bentonite (RB) locally available in Mostaganem (Algeria) deposit has been treated in the presence of NaOH (B-NaOH), MgCl2 (B-MgCl2) and H2SO4 (B-H2SO4) to improve its adsorption ability for the removal of copper ions from aqueous solutions. Characterization of all adsorbents supported montmorillonite, illite and kaolinite as major clay minerals identified for the raw and treated bentonites and proved the aluminosilicate structure of the clays. In synthetic solutions, the adsorption equilibrium of copper onto RB, B-MgCl2 and B-H2SO4 is reached in 30 min. while, equilibrium is reached after 4 hours when using B-NaOH. The adsorption kinetics are well described by the pseudo-second-order model. The adsorption of copper is pH-dependent. The Langmuir, Freundlich and Dubinin-Radushkevich isotherms indicate a suitable fit between the experimental data and models. The corresponding parameters indicate that the sorption mechanism might be physical in nature. The maximum adsorption capacities of Langmuir that are obtained are in the following order 25.1 mg/g (RB) < 28.03 mg/g (B-H2SO4) < 39.89 mg/g (B-MgCl2) < 72.80 mg/g (B-NaOH). The removal efficiency of copper in industrial wastewater was 45.75 %, 55.22 %, 63.27 % and 70.39 % using RB, B-MgCl2, B-H2SO4 and B-NaOH, respectively. The B-NaOH exhibit a higher adsorption capacity of copper with the other tested bentonites

Évolution des instruments de planification spatiale et de gestion urbaine en Algérie

The urban environment is in permanent degradation and the development of our cities is done against the directives instruments of planning and urbanism as well as monitoring and control tools, which created a gap between the legislation and practice of the indifference of the user and the administration with regard to the rules of urbanism. In this research, we are trying to detect urban policies in Algeria by analysing the different steps that have punctuated the evolution of urban planning to clarify the legal environment of practice of all the instruments of spatial and urban planning and flatten their effectiveness in the management of urban development in order to detect the shortcomings affecting the implementation. However, foreign models due to historical links which have enacted urban growth. In spite of the considerable efforts of the public authorities, despite the existence of a range of legislative and regulatory tools, and the development of instruments supposed to planning solutions to urban problems; the city continues its development without a real improvement in quality of life, gradually losing its identity cues and consuming of unrelated land potential.L’environnement urbain est en dégradation permanente et l'aménagement de nos villes se fait à l'encontre des directives des instruments de planification et d'urbanisme ainsi que des outils de gestion et de contrôle. Cela a engendré un écart entre la réglementation et la pratique du à l'indifférence de l'utilisateur et de l'administration vis-à-vis des règles d'urbanisme. Dans cette recherche, nous essayons de détecter les politiques urbaines en Algérie en analysant les différentes étapes qui ont jalonné l'évolution des instruments de planification spatiale et de gestion urbaine, tout en essayant de clarifier l'environnement juridique de la pratique urbanistique afin de mettre à plat leur efficacité dans la gestion du développement urbain et de déceler les défaillances entravant l'application de ces instruments qui sont opposable aux tiers. Cependant, nous soulignons, que malgré les efforts considérables de gestion courante consentis jusqu'à présent par les pouvoirs publics, malgré l'existence d'une panoplie d’outils législatifs et règlementaires, et malgré même l'élaboration des instruments d'urbanisme censés apporter des solutions aux problèmes urbains ville continue son développement sans une réelle amélioration de la qualité de vie ou de la qualité du cadre bâti, sans assise économique, en perdant progressivement ses repères identitaires et en consommant de manière irréfléchie son potentiel foncier

FLASH-RL: Federated Learning Addressing System and Static Heterogeneity using Reinforcement Learning

Federated Learning (FL) has emerged as a promising Machine Learning paradigm, enabling multiple users to collaboratively train a shared model while preserving their local data. To minimize computing and communication costs associated with parameter transfer, it is common practice in FL to select a subset of clients in each training round. This selection must consider both system and static heterogeneity. Therefore, we propose FLASH-RL, a framework that utilizes Double Deep QLearning (DDQL) to address both system and static heterogeneity in FL. FLASH-RL introduces a new reputation-based utility function to evaluate client contributions based on their current and past performances. Additionally, an adapted DDQL algorithm is proposed to expedite the learning process. Experimental results on MNIST and CIFAR-10 datasets have shown FLASH-RL's effectiveness in achieving a balanced trade-off between model performance and end-to-end latency against existing solutions. Indeed, FLASH-RL reduces latency by up to 24.83% compared to FedAVG and 24.67% compared to FAVOR. It also reduces the training rounds by up to 60.44% compared to FedAVG and +76% compared to FAVOR. In fall detection using the MobiAct dataset, FLASH-RL outperforms FedAVG by up to 2.82% in model's performance and reduces latency by up to 34.75%. Additionally, FLASH-RL achieves the target performance faster, with up to a 45.32% reduction in training rounds compared to FedAVG.Comment: Accepted in the 41st IEEE International Conference on Computer Design (ICCD 2023

ELIMINATION DES NITRATES PAR ADSORPTION SUR CHARBON ACTIF EN POUDRE

L’objectif de ce travail est de tester l’efficacité du charbon actif en poudre (CAP) comme adsorbant pour la rétention des nitrates, et d’étudier l’influence de divers paramètres réactionnels sur l’élimination de cet élément par le CAP en solutions synthétiques d’eau distillée. Les résultats que nous avons obtenus indiquent que le CAPpermet une bonne rétention des nitrates après 1heure 30 minutes de contact. Le pH de traitement influe sur les rendements d’élimination des nitrates. Les meilleurs rendements sont obtenus à pH égal à 4. Les rendements de dénitrification augmentent avec l’augmentation de la dose de l’adsorbant dans la gamme 0,1 à 4 g/l pour une teneur initiale en nitrate égale à 40 mg/l. Les modèles de Langmuir et de Freundlich s ont parfaitement applicables pour les résultats obtenus.Dans l’intervalle de concentration initiale de nitrate allant de 5 à 100 mg / litre d’eau distilléeet pour une dose constante de l’adsorbant (1 g/l), l’utilisation du CAP semble être efficace pour les eaux chargées en ce polluan t.   The aim of this work is to test the effectiveness of powdered activated carbon (PAC) as adsorbent for retention of nitrates, and to study the effect of various reaction parameters on the removal of this compound by the PAC in syn thetic solutions of distilled water. The results weobtained indicated that the use of PAC result at a good retention of nitrate after 1 hour 30 minutes of contact. The pH of treatment affects the nitrate removal efficiencies. The maximum removal is obtained at pH 4. Denitrification rates increase with increasing the dose of the adsorbent in the range 0,1 to 4 g/l for an initial content of nitrate equal to 40 mg/l. Langmuir and Freundlich models are perfectly appropriate to the results obtained. In the initial concentration of nitrate ranging from 5 to100 mg / liter of distilled water and a constant dose of adsorbent (1 g/l), the use of the PAC appears tobe effective for waters loaded by this pollutant

Trends in obesity and diabetes across Africa from 1980 to 2014: an analysis of pooled population-based studies

Background: The 2016 Dar Es Salaam Call to Action on Diabetes and Other non-communicable diseases (NCDs) advocates national multi-sectoral NCD strategies and action plans based on available data and information from countries of sub-Saharan Africa and beyond. We estimated trends from 1980 to 2014 in age-standardized mean body mass index (BMI) and diabetes prevalence in these countries, in order to assess the co-progression and assist policy formulation. Methods: We pooled data from African and worldwide population-based studies which measured height, weight and biomarkers to assess diabetes status in adults aged ≥ 18 years. A Bayesian hierarchical model was used to estimate trends by sex for 200 countries and territories including 53 countries across five African regions (central, eastern, northern, southern and western), in mean BMI and diabetes prevalence (defined as either fasting plasma glucose of ≥ 7.0 mmol/l, history of diabetes diagnosis, or use of insulin or oral glucose control agents). Results: African data came from 245 population-based surveys (1.2 million participants) for BMI and 76 surveys (182 000 participants) for diabetes prevalence estimates. Countries with the highest number of data sources for BMI were South Africa (n = 17), Nigeria (n = 15) and Egypt (n = 13); and for diabetes estimates, Tanzania (n = 8), Tunisia (n = 7), and Cameroon, Egypt and South Africa (all n = 6). The age-standardized mean BMI increased from 21.0 kg/m2 (95% credible interval: 20.3–21.7) to 23.0 kg/m2 (22.7–23.3) in men, and from 21.9 kg/m2 (21.3–22.5) to 24.9 kg/m2 (24.6–25.1) in women. The age-standardized prevalence of diabetes increased from 3.4% (1.5–6.3) to 8.5% (6.5–10.8) in men, and from 4.1% (2.0–7.5) to 8.9% (6.9–11.2) in women. Estimates in northern and southern regions were mostly higher than the global average; those in central, eastern and western regions were lower than global averages. A positive association (correlation coefficient ≃ 0.9) was observed between mean BMI and diabetes prevalence in both sexes in 1980 and 2014. Conclusions: These estimates, based on limited data sources, confirm the rapidly increasing burden of diabetes in Africa. This rise is being driven, at least in part, by increasing adiposity, with regional variations in observed trends. African countries’ efforts to prevent and control diabetes and obesity should integrate the setting up of reliable monitoring systems, consistent with the World Health Organization’s Global Monitoring System Framework

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks

Repositioning of the global epicentre of non-optimal cholesterol

High blood cholesterol is typically considered a feature of wealthy western countries(1,2). However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world(3) and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health(4,5). However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol-which is a marker of cardiovascular riskchanged from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million-4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.Peer reviewe