Interaction of two walkers: Wave-mediated energy and force

A bouncing droplet, self-propelled by its interaction with the waves it generates, forms a classical wave-particle association called a "walker." Previous works have demonstrated that the dynamics of a single walker is driven by its global surface wave field that retains information on its past trajectory. Here, we investigate the energy stored in this wave field for two coupled walkers and how it conveys an interaction between them. For this purpose, we characterize experimentally the "promenade modes" where two walkers are bound, and propagate together. Their possible binding distances take discrete values, and the velocity of the pair depends on their mutual binding. The mean parallel motion can be either rectilinear or oscillating. The experimental results are recovered analytically with a simple theoretical framework. A relation between the kinetic energy of the droplets and the total energy of the standing waves is established.Comment: 11 pages, 8 figure

Framing the Discourse, Advancing the Work: Philanthropy at the Nexus of Peace and Social Justice and Arts andCulture

Framing the Discourse, Advancing the Work Philanthropy at the Nexus of Peace and Social Justice and Arts andCulture is based on Moukhtar Kocache's research and his experience in this field of work; and information gathered through interviews with artists, cultural producers and philanthropy practitioners; and in a convening held in August 2013 in Ontario, Canada.It presents an overview of the relationship between progressive social change work and the arts, explores the role of philanthropy in supporting this work and sets out recommendations for how philanthropy might further its engagement with work at this nexus. The objective of the report is to stimulate further reflection and exchange of lessons and opportunities for inculcating practices in philanthropy for supporting arts and culture work as a means to advance social justice and peace.The process of compiling this report has been a journey and, like all journeys, it has involved changes of perspective and, like some journeys, a revision of ideas. During its course, it has become clear to us that arts and culture are not just a matter of better tools for supporting change; they are often central to personal and social transformation. The arts often reach us -- and influence us - in ways that direct explanation cannot. The call to philanthropy that seeks to support progressive social change is to recognise this transformational power of arts and culture and to engage with it as a holistic strategy.This argument will be presented more extensively in a brief paper (to be published in August 2014) entitled, 'Making the Case for the Arts to Social Justice Funders'

Method for determination of stable carbon isotope ratio of methylnitrophenols in atmospheric particulate matter

A technique for the measurement of the stable isotope ratio of methylnitrophenols in atmospheric particulate matter is presented. Atmospheric samples from rural and suburban areas were collected for evaluation of the procedure. Particulate matter was collected on quartz fibre filters using dichotomous high volume air samplers. Methylnitrophenols were extracted from the filters using acetonitrile. The sample was then purified using a combination of high-performance liquid chromatography and solid phase extraction. The final solution was then divided into two aliquots. To one aliquot, a derivatising agent, Bis(trimethylsilyl)trifluoroacetamide, was added for Gas Chromatography-Mass Spectrometry analysis. The second half of the sample was stored in a refrigerator. For samples with concentrations exceeding 1 ng μl<sup>−1</sup>, the second half of the sample was used for measurement of stable carbon isotope ratios by Gas Chromatography-Isotope Ratio Mass Spectrometry. <br><br> The procedure described in this paper provides a method for the analysis of methylnitrophenols in atmospheric particulate matter at concentrations as low as 0.3 pg m<sup>−3</sup> and for stable isotope ratios with an accuracy of better than ±0.5‰ for concentrations exceeding 100 pg m<sup>−3</sup>. <br><br> In all atmospheric particulate matter samples analysed, 2-methyl-4-nitrophenol was found to be the most abundant methylnitrophenol, with concentrations ranging from the low pg m<sup>−3</sup> range in rural areas to more than 200 pg m<sup>−3</sup> in some samples from a suburban location

Improving the quality of public health services in lower income areas in Cairo, Egypt: a comparative study between the accredited and non-accredited primary health care clinics in Cairo

This thesis deals with the quality of public health services in the primary health care clinics in lower income areas in Cairo. There are multiple factors affecting such quality, including the motivation of the workforce, the infrastructure and equipment of the facility, and the modes of finance and management. The research examines whether the accreditation of health clinics by the Egyptian Ministry of Health and Population affects these factors and hence improves the quality of the service provided. To do this, the research is based on a comparative study between accredited and non-accredited health care facilities; where accreditation is granted based on patients’ rights, patients’ care, environmental and clinical safety, information management, clinical and non clinical services, and management of the facility, quality improvement program, and integration of care. Although the accreditation period has expired for all accredited facilities in Cairo, some improvements to the quality of health care services were introduced as a result of the accreditation. Forty four interviews were conducted with public health workers and health service visitors (patients) in two accredited clinics and two non- accredited. The interviews were transcribed and data was analyzed using qualitative method of analysis. The results have shown that the accredited clinics are more organized, regularly inspected, and hence patients are more satisfied with the quality of service. However, it was noted that there are common impediments to improvement of health services in all public health clinics, like; poor equipments, old outdated devices, lack of utilities, and insufficient medicine supply; which act as de-motivating factors to most of the health workers. The thesis comes to the conclusion that these common factors point out to the need for wider reforms in the health service sector beyond introducing the accreditation system of public health clinics. These reforms should focus on a considerably more investment in the health service sector to modernize the service as well as improving the incentive system for health workers, improving the processes of purchase and maintenance of equipment, revising the essential drug list, and focusing on patients’ education

Impact des émissions naturelles sur les épisodes de pollution photochimique. Application à la région du fossé rhénan

Les Composés Organiques Volatils (COV) biotiques jouent un rôle significatif dans la formation et le développement d'épisodes de pollution photochimique. Leur forte réactivité et leur abondance dans la troposphère, en font des précurseurs significatifs de l'ozone, des PANs et du formaldéhyde. La prise en compte de ces COV par les modèles de prévision de la qualité de l'air se heurte aux incertitudes relatives à la quantification de leurs émissions et aux mécanismes chimiques de la troposphère dans lesquels ils sont impliqués. Dans ce contexte, la prise en compte des COV biotiques dans le modèle de chimie-transport CHIMERE a été améliorée en intégrant une double approche, numérique et expérimentale. Concernant les émissions biotiques, des mesures de terrain réalisées lors d'une campagne européenne, ont permis la détermination sur site de taux et flux d'émission de COV biotiques de trois espèces forestières très abondantes en France : Abies alba, Fagus sylvatica et Pseudotsuga menziesii, à partir de la méthode des cuvettes instrumentées. Ces résultats, complétés par une étude bibliographique, ont permis de mettre à jour la base de données des facteurs d'émission spécifique de la zone d'étude et de la France. Cette base de données a été utilisée pour estimer les émissions annuelles de COV par l'écosystème forestier français. Concernant la réactivité des COV biotiques, une synthèse critique de la bibliographie a conduit à l'élaboration d'un nouveau mécanisme chimique permettant de mieux modéliser leur réactivité. Les développements effectués ont abouti à une nouvelle version du modèle CHIMERE dont les résultats ont été évalués par rapport aux observation disponibles dans la région du Fossé Rhénan, région fortement émettrice de COV biotiques. Si la modélisation des concentrations d'ozone est peu affectée par les modifications apportées, la modélisation des concentrations de PANs et de formaldéhyde y est nettement sensible. Une importante étude de sensibilité relative à la prise en compte des COV biotiques dans les modèles, a permis de mettre en évidence la nécessité et la pertinence de réaliser des compromis et des simplifications pour modéliser la contribution des COV biotiques dans la formation d'épisode photochimique à l'ozone. Des mesures de terrain et des travaux pour affiner la connaissance des processus réactionnels seront néanmoins toujours nécessaires pour simuler correctement les autres polluants secondaires ainsi que les aérosols organiques

Sustainability of subsurface dams: What influences community satisfaction in Korlongo, a village in Chad?

Subsurface dams are important in improving water supply in arid and semi-arid regions; however, subsurface dams' sustainability depends largely on local community satisfaction. This study examines the factors influencing community satisfaction of the Korlongo village in Guéra, Chad. Data from 40 families representing 5% of the village population using the dam was collected using a questionnaire designed to collect data on the main factors influencing community satisfaction. These are the size of the family (adults), the size of the family (children), water consumption in litres per day, who transports water, community participation in building, operation and maintenance of the Dam and the community satisfaction level. The results show that the size of the family in terms of adults was small (62.5%), family size in terms of children was large (42.5%), water consumption per day is large (40.0%), young people (60.0%) who are transporting water. The community has been largely (95%) involved in the operation (no maintenance of the dam), and 72.5% is significantly involved in the construction of the dam's gravel well. Statistical analysis using linear regression  significantly predicted community satisfaction of the dam from the size of family (adults), size of family (children), water consumption in litres per day, who transports water, community participation in building, operation and maintenance of the Dam. The findings are important for the sustainability of the subsurface dam and will contribute to improving water management. Keywords: Sustainable subsurface dams, community participation and satisfaction, Cha

Management of High Urogenital Sinus in Adults: A Scoping Review

Background and Objectives: Persistent urogenital sinus (PUGS) is a rare congenital anomaly resulting from disruptions in urogenital development during embryogenesis. Characterized by the confluence of the vaginal canal and urethra into a single channel, it poses diagnostic and management challenges, particularly in adult patients. Surgical correction remains the primary treatment at an early age, yet there are no universally accepted guidelines regarding treatment at later stages in life. We explored current evidence on the management of high urogenital sinus (HUGS) in adults, focusing on surgical techniques, outcomes, perioperative care, and follow-up. Materials and Methods: A scoping review was conducted using PubMed, Scopus, and Google Scholar, including studies published up to August 2024. Search terms included "high urogenital sinus", "adult patients", and related conditions. Articles were included if they addressed clinical, diagnostic, or therapeutic data on HUGS in adult populations. Data extraction was performed independently by two reviewers, and a PRISMA-ScR flow diagram was used to outline the study selection process. Results: Nine studies met inclusion criteria, with data on surgical techniques, perioperative care, and long-term outcomes extracted for analysis. The included studies highlighted diverse surgical approaches, such as feminizing genitoplasty, buccal mucosa vaginoplasty, posterior prone techniques, and robotic-assisted urogenital sinus mobilization. Complications like vaginal stenosis, urethrovaginal fistula, and urinary incontinence were reported. Long-term outcomes were under-reported, with limited data on sexual function and patient satisfaction. Hormonal therapies, including glucocorticoids, played critical roles in managing cases associated with congenital adrenal hyperplasia (CAH). Conclusions: The management of HUGS requires a multidisciplinary approach integrating advanced surgical techniques and individualized perioperative care. While short-term outcomes are generally favorable, long-term data on sexual function and quality of life remain scarce. Future research should prioritize longitudinal studies to address these gaps, aiming to optimize surgical outcomes, patient satisfaction, and psychosocial well-being

ISO 14001 Environmental Management System Approvals In the economic institutions in Algeria

شهدت العقود الأخيرة ظهور وتطور مختلف الممارسات الإدارية المتعلقة بالجودة والبيئة ورغم هذا التطور، فإن تحليل تحليل أسباب لتبني هذه الممارسات الإدارية وآثارها على الشركات لم تحظ بالقدر الكافي من الدراسة والتحلي. وتساهم هذه الدراسة في الأدبيات التجريبية المتعلقة بالجودة البيئية في المؤسسات الإقتصادية في الجزائر، حيث قمنا بتحليل محددات اعتماد معايير ISO 14001 من طرف المؤسسات الإقتصادية في الجزائر بواسطة نموذج الانحدار اللوجستي وذلك باستخدام العديد من المتغيرات التي قد تؤثر على اعتماد ISO 14001  من قبل المؤسسات الاقتصادية في الجزائر. وتبين لنا أن المؤسسات الاقتصادية التي لديها منتجات للتصدير والمؤسسات الكبيرة والمؤسسات الإقتصادية التي تعتبر شركات النفط أحد عملائها هي المؤسسات الأكثر توجها نحو اعتماد معايير ISO 14001Recent decades have seen the emergence and development of various managerial practices that respect quality and the environment. However, analysis of the reasons for adopting these managerial practices by companies and their impact on businesses has been little studied by economists. The aim of this empirical study is to identify the factors that push economic companies in Algeria to adopt ISO 14001 standards. We analyze a logistic regression model that describe the relationship between several determinants and the adoption of ISO 14001 standards, using various variables that may impact the adoption of ISO 14001 standards by economic companies in Algeria. We conclude that the companies oriented to Export and that have a large business as also that transact with oil companies are more oriented to adopt ISO 14001 standards

In situ, satellite measurement and model evidence on the dominant regional contribution to fine particulate matter levels in the Paris megacity

International audiencePublished by Copernicus Publications on behalf of the European Geosciences Union. 9578 M. Beekmann et al.: Evidence for a dominant regional contribution to fine particulate matter levels Abstract. A detailed characterization of air quality in the megacity of Paris (France) during two 1-month intensive campaigns and from additional 1-year observations revealed that about 70 % of the urban background fine particulate matter (PM) is transported on average into the megacity from upwind regions. This dominant influence of regional sources was confirmed by in situ measurements during short intensive and longer-term campaigns, aerosol optical depth (AOD) measurements from ENVISAT, and modeling results from PMCAMx and CHIMERE chemistry transport models. While advection of sulfate is well documented for other megacities, there was surprisingly high contribution from long-range transport for both nitrate and organic aerosol. The origin of organic PM was investigated by comprehensive analysis of aerosol mass spectrometer (AMS), radio-carbon and tracer measurements during two intensive campaigns. Primary fossil fuel combustion emissions constituted less than 20 % in winter and 40 % in summer of carbonaceous fine PM, unexpectedly small for a megacity. Cooking activities and, during winter, residential wood burning are the major primary organic PM sources. This analysis suggests that the major part of secondary organic aerosol is of modern origin , i.e., from biogenic precursors and from wood burning. Black carbon concentrations are on the lower end of values encountered in megacities worldwide, but still represent an issue for air quality. These comparatively low air pollution levels are due to a combination of low emissions per inhabitant , flat terrain, and a meteorology that is in general not conducive to local pollution build-up. This revised picture of a megacity only being partially responsible for its own average and peak PM levels has important implications for air pollution regulation policies