Catechol-Modified Activated Carbon Prepared by the Diazonium Chemistry for Application as Active Electrode Material in Electrochemical Capacitor

Activated carbon (Black Pearls 2000) modified with electroactive catechol groups was evaluated for charge storage application as active composite electrode material in an aqueous electrochemical capacitor. High surface area Black Pearls 2000 carbon, was functionalized by introduction of catechol groups by spontaneous reduction of catechol diazonium ions in situ prepared in aqueous solution from the corresponding amine. Change in the specific surface area and pore texture of the carbon following grafting was monitored by nitrogen gas adsorption measurements. The electrochemical properties and the chemical composition of the catechol-modified carbon electrodes were investigated by cyclic voltammetry. Such carbon-modified electrode combines well the faradaic capacitance, originating from the redox activity of the surface immobilized catechol groups, to the electrochemical double layer capacitance of the high surface area Black Pearls carbon. Due to the faradaic contribution, the catechol-modified electrode exhibits a higher specific capacitance (250 F/g) than pristine Carbon (150 F/g) over a potential range of -0.4 to 0.75 V in 1 M H2SO4. The stability of the modified electrode evaluated by long-time 1 charge/discharge cycling revealed a low decrease of the capacitance of the catechol-modified carbon due to the loss of the 1 catechol redox activity. Nonetheless, it was demonstrated that the benefit of redox groups persists for 10 000 constant current charge/discharge cycles

Residues of synthetic hormones in pork, Madagascar

In Madagascar, little information is available on drug residues in animal products. Official veterinary services have been recently informed about the misuse of human injectable contraceptives in pig farms. Farmers and local animal health workers have been suspected of treating pigs for growth promotion and of using human progestins, especially medroxyprogesterone acetate (MPA), as a chemical alternative method for castration of sows that are then fattened before culling. Indeed, MPA may arrest the onset of farrowing and induce post-lactational anestrus in sows. Because the use of synthetic hormones in pig husbandry is consid¬ered a fraud by the Malagasy legislation, an exploratory study was carried out to confirm these suspicions and investigate the main molecules concerned. We investigated 80 pigs slaughtered in seven Malagasy abattoirs and raised in eight (out of 22) Malagasy regions (i) to confirm the contamination of carcasses by anabolic hormones by liquid chromatography coupled to mass spectrometry (LC-MS/MS), (ii) to identify the concerned molecules, and (iii) to explore consumers' exposure to hormone residues. Only adult sows were sampled con¬sidering that chemical castration with progestogens was the most common hypothesis of misuse of synthetic hormones in the field. The screening of the 80 kidney-fat samples did not reveal residues of progestogens other than MPA. MPA-positive samples were detected in 10 out of 15 districts (66.7%), and in all eight surveyed regions except one (87.5%), Diana Region in Northern Madagascar. Our results revealed heavy contamination of pork products by synthetic hormone residues; its prevalence was high considering that such residues are not supposed to occur accord¬ing to the Malagasy legislation. Investigations by Malagasy vet¬erinary services revealed that farmers and animal health workers purchased syringes of progestogens (Confiance™, Pfizer). These low-price progestins are easily available in private local dispen-saries and basic health centers (public sector). Without any control, farmers can easily administer MPA to pigs. It has thus become urgent to launch public-awareness campaigns and improve control within the sectors of animal production and public health over the entire country. (Résumé d'auteur

Surveillance of veterinary drug residues in pork meat in Madagascar

Antibiotics are used in animal feeds as growth promoters or for disease prevention and treatment. Drugs and their metabolites accumulate into body cells and constitute the so-called drug residues. Residual antimicrobials in food are an increasing risk for human health. Antibiotic residues in meat and other foods are suspected to be responsible for drug allergies and emergence of antimicrobial-resistant bacteria. In Madagascar, bacterial resistance against several antibiotics has been regularly observed in pathogens isolated from humans and pigs. Suspicion of drug misuse in farms has been frequently recorded by animal health professionals but no guidelines are available on the good usage of antibiotics in livestock. Since scarce information is available on antimicrobial residues in ani¬mal products in Madagascar, this study aimed at determining the prevalence of pork meat contaminated by such residues and sold in Antananarivo markets. A total of 967 meat samples (diaphragm muscle) were collected during 2010 and 2011 in the four main abattoirs of Antananarivo, and in three additional regional abattoirs, i.e. Antsirabe, Mahitsy (Central Madagascar) and Tsiroamandidy (Western Madagascar). Analysis for antimicrobial detection in meat was performed with the commercial Premi®-test kit (DSM, Urmond, Netherlands) at the National Veterinary Diagnostic Laboratory in Antananarivo. Premi®-test is a broad spectrum microbial screening test for the detection of antibiotic and sulfonamide residues in meat or meat products at, or below maximum residue limit (MRL) levels. MRL is the maximum concentration of residues following administration of a veterinary medicine which is legally permit¬ted or acceptable in food under European Union legislation. The Premi®-test kit contains a standardized number of spores of Bacillus stearothermophilus, very sensitive to many antibiotics and sulfa compounds, in agar medium with selected nutrients together with an indicator. Premi®-test is based on the inhibi¬tion of the growth of B. stearothermophilus. When meat juice is added to the Premi®-test ampoule and heated at 64°C, spores germinate. The germinated spores multiply and form an acid when no inhibitory substances are present, leading to an indica¬tor color change from purple to yellow. When antimicrobial mol¬ecules are present above the detection level, no growth occurs and the color remains purple. Table I presents the results of the percentage of positive samples in the various regions of Madagascar. On average 37.2% sam¬ples were contaminated by antimicrobial residues. A significant increase from 32 to 39% was observed between 2010 and 2011, respectively. No significant differences were found between samples according to sex, breed or age class in individual ani¬mals. No differences between pig farm origins were found either (Figure 1). However, Amoron'i Mania Region, and particularly suburban Ambositra, was the most contaminated area in 2010 (67%; n = 9) and Melaky region (Western Madagascar) in 2011. Pork meat samples originating from the same production area were less contaminated by drug residues when the animals were slaughtered in urban abattoirs compared to provincial abat¬toirs. In this first step toward a national surveillance system, we confirm that drug residues in animal products are a serious public health concern for Madagascar. (Résumé d'auteur

Cosmology and Cartography

This paper describes early cartographers' concepts of the world and its polar regions. Some comments on the relationships of astronomy to cartography are made (inclusion of Ptolemaic thought) and of the importance of technical method in cartography. Most of the paper is devoted to a description of medieval cartography and cosmology

Langues sub-étatiques et principes du droit : la dialectique de l’épreuve réciproque

La pluralité de l’expression idiomatique intra-nationale a été appréhendée diversement par les droits nationaux et international. Cette circonstance a partiellement expliqué le caractère tardif de la définition des langues infra-étatiques. Selon la Charte européenne sur les langues régionales ou minoritaires (ci-après la Charte) du 5 novembre 1992, “ pratiquées traditionnellement sur un territoire d’un Etat ” par ses ressortissants constituant “ un groupe numériquement inférieur au reste de l..

Impedance spectroscopy study of a catechol-modified activated carbon electrode as active material in electrochemical capacitor

Modified activated carbon (Norit S-50) electrodes with electrochemical double layer (EDL) capacitance and redox capacitance contributions to the electric charge storage were tested in 1 M H2SO4 to quantify the benefit and the limitation of the surface redox reactions on the electrochemical performances of the resulting pseudo-capacitive materials. The electrochemical performances of an electrochemically anodized carbon electrode and a catechol-modified carbon electrode, which make use both EDL capacitance of the porous structure of the carbon and redox capacitance, were compared to the performances obtained for the pristine carbon. Nitrogen gas adsorption measurements have been used for studying the impact of the grafting on the BET surface area, pore size distribution, pore volume and average pore diameter. The electrochemical behavior of carbon materials was studied by cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The EIS data were discussed by using a complex capacitance model that allows defining the characteristic time constant, the global capacitance and the frequency at which the maximum charge stored is reached. The EIS measurements were achieved at different dc potential values where a redox activity occurs and the evolution of the capacitance and the capacitive relaxation time with the electrode potential are presented. Realistic galvanostatic charge/discharge measurements performed at different current rates corroborate the results obtained by impedance

Ralph B. Stine and Margaret E. Stine v. Henry Girola and Diane Girola and State Underwriters, Inc. : Petition for Rehearing

In this paper we present a Remote Control Unit (RCU) that can be attached to any location on a rifle, binoculars, etc., and be operated by a single finger of a soldier without removing his hand from the device. Even for a gloved hand a haptic feedback from the RCU will be realized. A RCU prototype, equipped with a single button, is used as a remote Push-to-Talk (PTT) device for the radio being carried by the soldier. The RCU is powered by the radio waves emitted by this radio. The RCU - being attached to the device - works with a receive unit (RXU) that is attached to and operates the radio. The RCU consists of a RF harvester, energy storage device, a button and a transmitter. Laboratory prototypes are demonstrated

Aspects Épidémiologiques, Cliniques et Thérapeutiques des Tumeurs de la Parotide

Introduction: Les pathologies des glandes salivaires sont relativement rares, dominées par les tumeurs de la glande parotide. Elles sont caractérisées par leur polymorphisme clinique et leur grande diversité morpho-histologique. Le traitement est surtout chirurgical, la complication majeure de cette chirurgie reste la paralysie faciale pouvant être transitoire ou permanente. Dans ce sens, l’objectif de ce travail était de décrire les aspects épidémiologiques, cliniques, paracliniques et thérapeutiques des tumeurs parotidiennes rencontrées dans le service de l’odontostomatologie de l’Hôpital National de Niamey (HNN) durant la période de l’étude. Méthodologie: Il s’agissait d’une étude rétrospective et descriptive portant sur les tumeurs parotidiennes rencontrées au service d’odontostomatologie de l’Hôpital National de Niamey au Niger. Par ailleurs, la tumeur était homogène dans 2 cas sur 4 et bénigne également une fois sur 2. Résultats: 12 patients ont été colligés sur une période de 29 mois. La prévalence hospitalière était de 0,11% avec 4,97 cas par an. La tranche d’âge allait de 9 à 75 ans. Il y avait 8 hommes contre 4 femmes. La malignité a été suspectée cliniquement devant une masse dure, fixe, douloureuse avec présence d’adénopathies satellites et associée à une paralysie faciale. La parotidectomie totale conservatrice du nerf facial a été réalisée chez 10 patients sur 12 et la chimiothérapie a été préconisée chez 2 patients. L’examen ophtalmologique a été réalisé chez tous les patients à la recherche d’une atteinte oculaire ou de la glande lacrymale. L’histologie a été contributive dans tous les cas et les tumeurs bénignes dominaient dans 50% des cas avec comme chef de fil l’adénome pléomorphe. Conclusion: Les tumeurs de la glande parotide sont rares et leur prise en charge thérapeutique est essentiellement chirurgicale. Leur évolution est en général favorable. Néanmoins, l’accent devra être mis sur la surveillance à long terme de certaines formes histologiques dont le risque de dégénérescence et de récidive est élevé.  Introduction: Pathologies of the salivary glands are relatively rare and are dominated by tumors of the parotid gland. They are characterized by their clinical polymorphism and their great morpho-histological diversity. The treatment is mainly surgical. The major complication of this surgery is facial paralysis which can be transient or permanent. The objective of this work is to describe the epidemiological, clinical, paraclinical, and therapeutic aspects of parotid tumors encountered in the odontostomatology department of Niamey National Hospital during the study period. Methodology: This study is a retrospective and descriptive study on parotid tumors encountered in the odontostomatology department of the Niamey National Hospital in Niger. In addition, the tumor was homogeneous in 2 out of 4 cases and also benign once in 2. Results: 12 patients were collected over a period of 29 months. The hospital prevalence was 0.11% with 4.97 cases per year. The age range was from 9 to 75 years old. There were 8 men against 4 women. The malignancy was suspected clinically before a hard, fixed, and painful mass with the presence of satellite lymphadenopathy which is associated with facial paralysis. Total conservative facial nerve parotidectomy was performed in 10 out of 12 patients, and chemotherapy was recommended in 2 patients. The ophthalmic examination was performed in all patients looking for damage to the eyes or the lacrimal gland. Histology was contributory in all cases and benign tumors dominated in 50% of cases with pleomorphic adenoma as the lead. Conclusion: Tumors of the parotid gland are rare and their therapeutic management is essentially surgical. Their development is generally favorable. However, emphasis should be placed on the long-term monitoring of certain histological forms for which the risk of degeneration and recurrence is high.&nbsp

Adaptive priority scheduling of Internet of Things data for disaster management in smart cities

ABSTRACT: In the recent context of the emergence of smart cities, the massive amount of data generated by connected objects has led to unprecedented demands in terms of data transfer. The various constraints linked to their number, their characteristics, and their transmission are even greater and dim the effectiveness, in their regard, of traditional data planning schemes. As a result, the need to minimize the delivery time of urgent packets while reducing the average data delay, the difficulty in choosing and combining the appropriate criteria for classifying and prioritizing data, and the loss of packets are of continuing concern. In this paper, we propose an adaptive scheduling model based on multilevel priority packet classification, preemptive packet queuing with dynamic and adaptive reordering, contingency migration of packets in critical situations, and adaptive criticality-based selection of packet next-hop. We introduce two new parameters for scheduling decisions: the ratio of per-level deadlines reflecting the evolution of a packet in the network and the migration coefficient based on the experience of same-characteristic packets. Performance evaluation shows that the proposed model effectively prevents data loss and prioritizes the transfer of emergency data over a hierarchical wireless sensor network. Moreover, it guarantees the shortest delays for urgent data with an improvement of 31% and promotes fairness toward less urgent ones. The lowest delivery rate observed with the proposed method is 99.9%

Connaissances, attitudes et pratiques des professionnels de santé en matière de cancer du col de l’utérus dans la commune de Parakou (Bénin) en 2024

Introduction : En Afrique et dans les pays en développement, le cancer du col de l’utérus est le cancer le plus diagnostiqué chez les femmes  Objectifs : évaluer le niveau de connaissances, d’attitude et de pratique des professionnels de santé en matière de cancer du col utérin dans la commune de Parakou au Bénin. Méthodes :il s’est agi d’une étude transversale descriptive, à visée analytique avec collecte prospective de données, réalisée sur une période de 09 semaines allant du 1er juillet au 05 septembre, impliquant les professionnels de santé de la commune de Parakou. Résultats : Au total 116 professionnels de santé avaient participé à l’étude.  L'âge moyen était de 29 ± 6,62 ans, avec des extrêmes de 21 à 52 ans. Parmi eux, 92,17 % connaissaient le HPV comme facteur de risque principal ; 52,17 % ignoraient l'existence de vaccins. Le niveau de connaissance sur le cancer du col de l’utérus était globalement insuffisant (46,55 %). Quatre-vingt-dix-huit virgule vingt-huit pour cent (98,28 %) considéraient le CCU comme une affection grave. Concernant le dépistage, 46,55 % estimaient qu'il était bien organisé et 77,59 % soutenaient un dépistage systématique. Globalement, 51,72 % avaient une attitude juste face au CCU. En pratique, 80,17 % sensibilisaient leurs patientes sur les facteurs de risque, et 69 % avaient procédé au dépistage. Parmi eux, 76,25 % utilisaient l'IVA/IVL, 32,50 % le test HPV et 17,50 % le FCV. Seulement 6,45 % prescrivaient le FCU systématiquement. Au total, 38,79 % avaient une pratique adéquate, et 89,66 % des agents avaient un score CAP global acceptable, influencé par le secteur d’activité, l’absence de formation continue, la catégorie socio-professionnelle infirmier et le sexe masculin.  Conclusion : Ces résultats soulignent la nécessité de formations médicales continues des professionnels de santé sur le diagnostic et la prise en charge de cette pathologie.   Introduction: In Africa and developing countries, cervical cancer is the most commonly diagnosed cancer among women.  Objectives:  to assess the level of knowledge, attitudes, and practices of healthcare professionals regarding cervical cancer in the municipality of Parakou in Bénin. Methods: This was a descriptive cross-sectional study, with an analytical aim and prospective data collection, carried out over a period of 9 weeks from July 1 to September 5, involving health professionals in the commune of Parakou  . Results: A total of 116 health professionals participated in the study. The average age of participants was 29 ± 6.62 years, ranging from 21 to 52 years. 92.17% were aware of HPV as the main risk factor; 52.17% were unaware of the existence of vaccines. Overall knowledge about cervical cancer was inadequate (46.55%). 98.28% considered cervical cancer a serious condition. Regarding screening, 45.55% felt it was well organized, and 77.59% supported systematic screening. Overall, 51.72% had an appropriate attitude toward cervical cancer. In practice, 80.17% raised awareness among their patients about risk factors, and 69% had conducted screenings. Among them, 76.25% used IVA/IVL, 32.50% used the HPV test, and 17.50% used the FCU. Only 6.45% prescribed the FCV systematically. In total, 38.79% had adequate practice, and 89.66% of the healthcare providers had an acceptable overall CAP score, influenced by the sector of activity, absence of continuing education, socio-professional category, and gender. Conclusion: These results highlight the need for ongoing training of healthcare professionals to improve the early diagnosis and management of this condition