63 research outputs found
Study of the Thermal Behavior of Almond Shells and Acorn Cups for Production of Fuel Briquettes
Because of the importance of his field, its neutrality in terms of pollution, biomass sector is an attractive way for the promotion of renewable energies, the fight against deforestation and the protection of our environment. In Morocco, almond shells and acorn cups are still rejected as a solid waste, while they can be a source of renewable energy and provide a continuous supply of solid liquid and gas fuels, through a thermochemical conversion. The conversion of acorn cups and almond shells to energy by thermochemical conversion processes requires a fundamental understanding of their thermal properties. The purpose of this research is to investigate the thermal behavior of these wastes, its energy recovery by the production of fuel briquettes from roasted fine and to study combustion behavior of these briquettes. The results of thermogravimetry (TGA), derivate thermogravimetry (DTG) and differential thermal (DTA) analysis allowed us to determine the stages of thermal decomposition of acorns cups and almond shells and associated phenomena. Characterization of briquettes showed us that the particle size and residence time during roasting are the determinants factors of their quality. Keywords: Renewable energy, fuel briquettes, almond shells, acorn cups
Towards an Analytical Habitability Grid for Heritage: the Medina of Mostaganem as a Case Study
Conservation of historic cities is limited in many countries to valorization and safeguarding which is performed utilizing several types of interventions. Many countries aware of the importance of their heritage in the development of human life, are currently concerned with their inhabitants’ participatory role in conservation. The historic cities in Algeria are not immune to this fact. Nowadays, particular attention is paid to the quality of life in historic Algerian cities which are in continuous transformation. It has become an urgent issue to inquire into the state of these medinas. The aim of this article is to design an analysis grid of habitability for these historical cities in order to interpret the quality of life, as well as the understanding of the man-made quest for ideal livability. The adopted methodology is divided into two parts: first, making the grid and second, its projection and analysis. Application of the grid requires very diverse data and a field of study. For this purpose, several tools were mobilized: a questionnaire survey, field measurements and direct diagnosis. For a positive outcome to the research, fieldwork is essential. This is the case study of the Medina of Mostaganem.La conservazione delle città storiche è limitata, in molti Paesi, alla valorizzazione e alla salvaguardia che viene eseguita utilizzando diversi tipi di interventi. Molti Paesi, consapevoli dell'importanza del loro patrimonio nello sviluppo della vita umana, sono attualmente interessati al ruolo partecipativo dei loro abitanti nella conservazione. Le città storiche in Algeria non sono immuni da questo fatto.Oggigiorno, particolare attenzione è rivolta alla qualità della vita nelle città storiche algerine che sono in continua trasformazione. Analizzare lo stato di queste città storiche è diventato un problema urgente. Lo scopo di questo articolo è di progettare una metodologia di analisi di abitabilità al fine di interpretare la qualità della vita e comprendere gli standard di vivibilità ideale.La metodologia adottata è divisa in due parti: la griglia e la sua proiezione e analisi. L'applicazione della griglia richiede dati molto diversi e un settore di studio. A tal fine, sono stati utilizzati diversi strumenti: un questionario, misurazioni sul campo e analisi diretta. Per il positivo risultato della ricerca è essenziale il lavoro sul campo: il caso studio presentato é relativo alla città di Mostaganem
Effect of Different Stages of Chronic Kidney Disease and Renal Replacement Therapies on Oxidant-Antioxidant Balance in Uremic Patients
Oxidative stress seems to be involved in the path physiology of cardiovascular complications of chronic kidney disease (CKD). In this study, we determined the effect of different stages of CKD and substitutive therapies on oxidative stress. One hundred sixty-seven patients (age: 44±06 years; male/female: 76/91) with CKD were divided into 6 groups according to the National Kidney Foundation classification. Prooxidant status was assessed by assaying thiobarbituric acid reactive substances, hydroperoxides, and protein carbonyls. Antioxidant defence was performed by analysis of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, vitamin E, Iron, and bilirubin. TBARS and LPO were higher in HD patients compared to other groups (P<0.001), while protein carbonyls were more increased in PD patients. The antioxidant enzymes were declined already at severe stage of CKD and they were declined notably in HD patients (P<0.001). Similar observation was found for vitamin E, Fe, and bilirubin where we observed a significant decrease in the majority of study groups, especially in HD patients (P<0.001). The evolution of CKD was associated with elevated OS. HD accentuates lipid, while PD aggravates protein oxidation. However, the activity of antioxidant enzymes was altered by impaired renal function and by both dialysis treatments
Compte-rendu du livre Humanités numériques : la culture face aux nouvelles technologies de Dominique Vinck
D'après les auteurs de ce compte rendu du livre "Humanités numériques : la culture face aux nouvelles technologies" publié en avril 2016 par Dominique Vinck, ce dernier montre que les humanités numériques vont bien au-delà de la bonne maîtrise de l'informatique. Il examine les relations entre les sciences, les techniques et les sociétés à l'ère du numérique. Il analyse les transformations subies par les sciences humaines et sociales (SHS) ainsi que les nouvelles relations qu'elles créent. Pour faciliter l'organisation de son analyse, Vinck utilise une structure en question/réponse et commence par la question de la définition des humanités numériques (HN). Il souligne, en ouverture, la difficulté de définir les Humanités Numériques et de cerner leur périmètre. Il explique également comment les technologies numériques et leurs entreprises peuvent être à la fois des préservateurs des patrimoines culturels mondiaux et des renforçateurs d'inégalités et de fractures numériques. Il évoque certaines pratiques que certains pays du Nord adoptent pour contrôler, voler ou s’approprier : par la reproduction illégale, la commercialisation et l’utilisation non autorisée des patrimoines culturels des pays de Sud. L’auteur encourage les États à prendre des mesures pour protéger leur propriété intellectuelle. Il suggère également que les pays du Nord travaillent avec les pays du Sud pour promouvoir la numérisation, l'utilisation et l'appropriation équitable de ces patrimoines culturels.
α-Ba2P2O7
Single crystals of α-Ba2P2O7, dibarium diphosphate, were obtained by solid-state reaction. The orthorhombic structure is isotypic with α-Sr2P2O7 and is the second polymorph obtained for this composition. The structure is built from two different BaO9 polyhedra (both with m symmetry), with Ba—O distances in the ranges 2.7585 (10)–3.0850 (6) and 2.5794 (13)–2.9313 (4) Å. These polyhedra are further linked by sharing corners along [010] and either edges or triangular faces perpendicularly to [010] to form the three-dimensional framework. This polyhedral linkage delimits large channels parallel to [010] where the P2O7 diphosphate anions are located. These groups (symmetry m) are characterized by a P—O—P angle of 131.52 (9)° and an eclipsed conformation. They are connected to the BaO9 polyhedra through edges and corners
Comparative study of total phenolic content and antioxidant properties of Quercus fruit: flour and oil.
Aim:The currentstudywas undertaken to determinethe total phenolic and flavonoid contents and toassessthe antioxidant activity of two different extracts (flour and oil) of two Algerian Quercus species, Quercus ilexL. and Quercus suberL. Methods and Material:The oil extraction of the two species was achieved using the Soxhlet method. The obtained extracts were estimated for the chemical and physical constants (acidity, peroxide value, iodine value,and ultraviolet absorption indices). Total phenolic content was measuredby spectrophotometryaccording to the Folin-Ciocalteu procedure and calculated as gallic acid equivalents (GAE). The studied extracts were alsosubmitted to an estimation of their flavonoid contents too,using aluminum chloride methods. Antioxidant ability was assessed by means oftwo distinctmethods (DPPH• and ABTS•+).Results:The obtained results revealed that antioxidant properties, total phenolic,and total flavonoid contents differed significantly among selected species and extracts. The flour samples possessed the highest level of totalphenolic contents (1101–1464 mg GAE/kg dry weight) and exhibited the highest antioxidant capacities with average values of 52.62–40.78 μmol TE g−1dry weight and 36.19–44.50 μmol TE g−1dry weight for DPPH and ABTS assays, respectively. Acorn oil extractsshowed also remarkable antioxidant activity, up to 2.69 and 3.23 μmol TE g−1oil (DPPH and ABTS test, respectively), even though the total phenolic contents were low (195.64–322.06 mg GAE /kg of oil). Total phenolic amounts were positively correlated withtheantioxidant properties of Quercus flour and oil.Conclusions:Ourstudy provides basic information on the presence of bioactive compounds and antioxidant capacity in acorn fruits, in order to consider their extracts as functional food ingredients and potential source of natural antioxidants
Effect of Different Stages of Chronic Kidney Disease and Renal Replacement Therapies on Oxidant-Antioxidant Balance in Uremic Patients
Oxidative stress seems to be involved in the path physiology of cardiovascular complications of chronic kidney disease (CKD). In this study, we determined the effect of different stages of CKD and substitutive therapies on oxidative stress. One hundred sixtyseven patients (age: 44 ± 06 years; male/female: 76/91) with CKD were divided into 6 groups according to the National Kidney Foundation classification. Prooxidant status was assessed by assaying thiobarbituric acid reactive substances, hydroperoxides, and protein carbonyls. Antioxidant defence was performed by analysis of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, vitamin E, Iron, and bilirubin. TBARS and LPO were higher in HD patients compared to other groups ( < 0.001), while protein carbonyls were more increased in PD patients. The antioxidant enzymes were declined already at severe stage of CKD and they were declined notably in HD patients ( < 0.001). Similar observation was found for vitamin E, Fe, and bilirubin where we observed a significant decrease in the majority of study groups, especially in HD patients ( < 0.001). The evolution of CKD was associated with elevated OS. HD accentuates lipid, while PD aggravates protein oxidation. However, the activity of antioxidant enzymes was altered by impaired renal function and by both dialysis treatments
Impact of conflict on maternal and child health service delivery: A country case study of Afghanistan
Introduction: Since decades, the health system of Afghanistan has been in disarray due to ongoing conflict. We aimed to explore the direct effects of conflict on provision of reproductive, maternal, newborn, child and adolescent health and nutrition (RMNCAH&N) services and describe the contextual factors influencing these services.Method: We conducted a quantitative analysis of secondary data on RMNCAH&N indicators and undertook a supportive qualitative study to help understand processes and contextual factors. For quantitative analysis, we stratified the various provinces of Afghanistan into minimal-, moderate- and severe conflict categories based on battle-related deaths from Uppsala Conflict Data Program (UCDP) and through accessibility of health services using a Delphi methodology. The coverage of RMNCAH&N indicators across the continuum of care were extracted from the Demographic and Health Surveys (DHS) and Multiple Indicator Cluster Survey (MICS). The qualitative data was captured by conducting key informant interviews of multi-sectoral stakeholders working in government, NGOs and UN agencies.Results: Comparison of various provinces based on the severity of conflict through Delphi process showed that the mean coverage of various RMNCAH&N indicators including antenatal care (OR: 0.42, 95%CI: 0.32-0.55), facility delivery (OR: 0.42, 95%CI: 0.32-0.56), skilled birth attendance (OR: 0.43, 95%CI: 0.33-0.57), DPT3 (OR: 0.26, 95% CI: 0.20-0.33) and oral rehydration therapy (OR: 0.37, 95% CI: 0.25-0.55) was significantly lower for severe conflict provinces when compared to minimal conflict provinces. The qualitative analysis identified various factors affecting decision making and service delivery including insecurity, cultural norms, unavailability of workforce, poor monitoring, lack of funds and inconsistent supplies. Other factors include weak stewardship, capacity gap at the central level and poor coordination at national, regional and district level.Conclusion: RMNCAH&N service delivery has been significantly hampered by conflict in Afghanistan over the last several years. This has been further compromised by poor infrastructure, weak stewardship and poor capacity and collaboration at all levels. With the potential of peace and conflict resolution in Afghanistan, we would underscore the importance of continued oversight and integrated implementation of sustainable, grass root RMNCAH&N services with a focus on reaching the most marginalized
Impact of conflict on maternal and child health service delivery - how and how not: A country case study of conflict affected areas of Pakistan
Introduction: In conflict affected countries, healthcare delivery remains a huge concern. Pakistan is one country engulfed with conflict spanning various areas and time spans. We aimed to explore the effect of conflict on provision of reproductive, maternal, newborn, child and adolescent health and nutrition (RMNCAH&N) services and describe the contextual factors influencing the prioritization and implementation in conflict affected areas of Pakistan (Balochistan and FATA).Method: We conducted a secondary quantitative and a primary qualitative analysis. For the quantitative analysis, we stratified the various districts/agencies of Balochistan and FATA into the conflict categories of minimal-, moderate- and severe based on accessibility to health services through a Delphi methodology with local stakeholders and implementing agencies and also based on battle-related deaths (BRD) information from Uppsala Conflict Data Program (UCDP). The coverage of RMNCAH&N indicators across the continuum of care were extracted from the demographic and health surveys (DHS) and district health information system (DHIS). We conducted a stratified descriptive analysis and multivariate analysis using STATA version 15. The qualitative data was captured by conducting key informant interviews of stakeholders working in government, NGOs, UN agencies and academia. All the interviews were audiotaped which were transcribed, translated, coded and analyzed on Nvivo software version 10.Results: The comparison of the various districts based on the severity of conflict through Delphi process showed that the mean coverage of various RMNCAH&N indicators in Balochistan were significantly lower in severe- conflict districts when compared to minimal conflict districts, while there was no significant difference between moderate and severe conflict areas. There was no reliable quantitative data available for FATA. Key factors identified through qualitative analysis, which affected the prioritization and delivery of services included planning at the central level, lack of coordination amongst various hierarchies of the government and various stakeholders. Other factors included unavailability of health workforce especially female workers, poor quality of healthcare services, poor data keeping and monitoring, lack of funds and inconsistent supplies. Women and child health is set at a high priority but capacity gap at service delivery, resilience from health workers, insecurity and poor infrastructure severely hampers the delivery of quality healthcare services.Conclusion: Conflict has severely hampered the delivery of health services and a wholesome effort is desired involving coordination amongst various stakeholders. The multiple barriers in conflict contexts cannot be fully mitigated, but efforts should be made to negate these as much as possible with good governance, planning, efficiency and transparency in utilization of available resources
- …