43 research outputs found

    Direct observation of ion dynamics in supercapacitor electrodes using in situ diffusion NMR spectroscopy

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    Ionic transport inside porous carbon electrodes underpins the storage of energy in supercapacitors and the rate at which they can charge and discharge, yet few studies have elucidated the materials properties that influence ion dynamics. Here we use in situ pulsed field gradient NMR spectroscopy to measure ionic diffusion in supercapacitors directly. We find that confinement in the nanoporous electrode structures decreases the effective self-diffusion coefficients of ions by over two orders of magnitude compared with neat electrolyte, and in-pore diffusion is modulated by changes in ion populations at the electrode/electrolyte interface during charging. Electrolyte concentration and carbon pore size distributions also affect in-pore diffusion and the movement of ions in and out of the nanopores. In light of our findings we propose that controlling the charging mechanism may allow the tuning of the energy and power performances of supercapacitors for a range of different applications

    Agradecimientos

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    Deseamos ofrecer nuestro agradecimiento, en primer lugar, al señor Gobernador del estado de San Luis Potosí, así como a las dos instituciones siguientes, Instituto Nacional de Antropología e Historia y Fomento Cultural Banamex, quienes, en forma de fideicomiso, financiaron esta magnífica publicación coeditada con el Centro Francés de Estudios Mexicanos y Centroamericanos. Ya desde la aparición del primer tomo de la obra, la doctora Celia Gonzålez de Vega, directora de Planeación del Instituto..

    Management and outcome of bloodstream infections: a prospective survey in 121 French hospitals (SPA-BACT survey)

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    Oliver Robineau,1 Jérome Robert,2 Christian Rabaud,3 Jean-Pierre Bedos,4 Emmanuelle Varon,5 Yves Péan,6 Rémy Gauzit,7 Serge Alfandari8 On behalf of the Société de Pathologie Infectieuse de Langue Française (SPILF), the Observatoire National de l’Épidémiologie de la Résistance Bactérienne aux Antibiotiques (ONERBA), and the Surveillance de la Prescription des Antibiotiques (SPA) Group 1Infectious Disease Department, Dron Hospital, Univ Lille, Tourcoing, 2Sorbonne University, UPMC Univ Paris 06, CR7, CIMI, Team E13 (Bacteriology), Paris, 3Infectious Disease Department, Nancy University Hospital, Nancy, 4Intensive Care Unit, Henri Mignot Hospital, Le Chesnay, 5Bacteriology Laboratory, HEGP, 6Observatoire National de L’epidémiologie de la Résistance Bactérienne aux Antibiotiques (OneRBa), 7Intensive Care Unit, Cochin Hospital, APHP, Paris, 8Intensive Care Unit, Dron Hospital, Tourcoing, France Background: Bloodstream infections (BSIs) are severe infections that can be community or hospital acquired. Effects of time to appropriate treatment and impact of antimicrobial management team are discussed in terms of outcome of BSI. We sought to evaluate the impact of initial BSI management on short-term mortality. Patients and methods: A prospective, multicenter survey was conducted in 121 French hospitals. Participants declaring BSI during a 1-month period were included consecutively. Data on patient comorbidities, illness severity, BSI management, and resistance profile of bacterial strains were collected. Predictors of 10-day mortality were identified by multivariate regression for overall BSI, health care-related and hospital-acquired BSI. Results: We included 1,952 BSIs. More than a third of them were hospital acquired (39%). Multidrug resistance was identified in 10% of cases, mainly in health care-related BSI. Empirical therapy and targeted therapy were appropriate for 61% and 94% of cases, respectively. Increased 10-day mortality was associated with severe sepsis, septic shock, increasing age, and any focus other than the urinary tract. Decreased mortality was associated with receiving at least one active antibiotic within the first 48 hours. Intervention of antimicrobial management team during the acute phase of BSI was associated with a decreased mortality at day 10 in the overall population and in health care-related BSI. Conclusion: Optimizing BSI management by increasing rapidity of appropriate treatment initiation may decrease short-term mortality, even in countries with low rate of multidrug-resistant organisms. Early intervention of antimicrobial management team is crucial in terms of mortality. Keywords: mortality, bloodstream infections, antimicrobial management team, community-acquired infection, health care-related infectio

    EnquĂȘte SPA2 de prĂ©valence et de bon usage des anti-infectieux dans 314 hĂŽpitaux français en 2010

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    International audienceObjectivesWe aimed to assess antibiotic prescriptions to identify potential targets for improvement.MethodsWe conducted a point prevalence survey (November 2010) of antibiotic use in 314 voluntary hospitals recruited by the French Infectious Diseases Society (SPILF) and the National Observatory for Epidemiology of Bacterial Resistance to Antimicrobials (ONERBA). Data were entered online, immediately analyzed and exported.ResultsThe prevalence of antibiotic use was 19.5% (9059/46,446patients). A higher prevalence was observed in the infectious disease (58.4%), hematology (58%), and intensive care (48.7%) units. The three most frequently used antibiotic classes were aminopenicillins (23.8%), fluoroquinolones (17.9%), and 3rd-generation cephalosporins (16.7%). A monotherapy was prescribed to 64% of patients. The reasons for the antibiotic prescription were written in the medical records of 74% of patients and 62% were consistent with the local guidelines.ConclusionOur results are similar to that of other studies. Various local targets for improvement have been identified to help hospitals define a better antibiotic stewardship.ObjectifsÉvaluer les prescriptions antibiotiques afin de proposer des pistes d’amĂ©lioration.MĂ©thodesNous avons rĂ©alisĂ© une enquĂȘte de prĂ©valence de l’antibiothĂ©rapie, en novembre 2010, dans 314 hĂŽpitaux volontaires recrutĂ©s par les rĂ©seaux de la SPILF et de l’ONERBA. Les donnĂ©es Ă©taient saisies en ligne avec une analyse instantanĂ©e et un export des donnĂ©es.RĂ©sultatsLa prĂ©valence de l’antibiothĂ©rapie Ă©tait de 19,5 % (9059/46 446patients). Elle Ă©tait plus Ă©levĂ©e en maladies infectieuses (58,4 %), hĂ©matologie (58 %) et rĂ©animation (48,7 %). Les trois classes les plus frĂ©quentes Ă©taient les aminopĂ©nicillines (23,8 %), les fluoroquinolones (17,9 %) et les cĂ©phalosporines de 3e gĂ©nĂ©ration (16,7 %). Une monothĂ©rapie Ă©tait utilisĂ©e dans 64 % des cas. Le motif de la prescription Ă©tait notĂ© dans le dossier mĂ©dical dans 74 % des cas et Ă©tait conforme aux recommandations locales dans 62 %.ConclusionsCes rĂ©sultats sont similaires Ă  ceux d’autres enquĂȘtes. Des possibilitĂ©s d’amĂ©lioration sur des critĂšres locaux permettent aux Ă©tablissements d’orienter leurs politiques d’amĂ©lioration de la prescription

    Application of guidelines for aminoglycosides use in French hospitals in 2013–2014

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    on behalf of the SociĂ©tĂ© de Pathologie Infectieuse de Langue Française (SPILF), the Observatoire National de l’EpidĂ©miologie de la RĂ©sistance BactĂ©rienne aux Antibiotiques (ONERBA) and the Surveillance de la Prescription des Antibiotiques (SPA) groupInternational audienceIn 2011, the French Agency for Safety of Health Products issued guidelines underlining the principles of proper aminoglycosides’ use. The aim of the survey was to evaluate adherence to these guidelines two years after their issue. Characteristics of patients receiving aminoglycosides were recorded by voluntary facilities during a 3-month survey in 2013–2014. The modalities of aminoglycosides treatment were analysed by comparison with the French guidelines. A total of 3,323 patients were included by 176 facilities. Patients were mainly hospitalized in medical wards (33.0%), and treated for urinary-tract infections (24.7%). Compliance regarding the clinical indication and the daily aminoglycosides dose was observed in 65.2% and 62.9% of the cases, respectively. A 30-min once-daily IV administration was recorded in 62.5% of the cases. Aminoglycosides treatment duration was appropriate (≀5 days) for 93.6% of the patients. When considering the four criteria together, 23.2% of the patients had a treatment regimen aligned with the guidelines. Requests for measurements of peak and trough AG serum concentrations matched the guidelines in 24.9% and 67.4% of the cases, respectively. Two years after guidelines issue, aminoglycosides use remains unsatisfactory in French health-care facilities. Efforts should be made for guidelines promotion, especially regarding the issue of underdosing

    Point prevalence survey of antibiotic use in French hospitals in 2009.

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    International audienceOBJECTIVES: To evaluate the feasibility of a point prevalence survey for monitoring antibiotic use in a voluntary sample of French hospitals. METHODS: Demographic and medical data were collected for all inpatients. Additional characteristics regarding antimicrobial treatment, type of infection and microbiological results were collected only for patients receiving antimicrobials. RESULTS: Among 3964 patients in 38 hospitals, 343 (8.7%) received antimicrobial prophylaxis and 1276 (32.2%) antimicrobial therapy. The duration of surgical antimicrobial prophylaxis was >1 day in 41 out of 200 (21%) of the cases. Among patients with antimicrobial therapy, 959 (75.2%) received ÎČ-lactams (including 34.8% penicillins with ÎČ-lactam inhibitors, 22.1% third-generation cephalosporins and 7.8% carbapenems) and 301 (23.6%) received fluoroquinolones (50% orally). A total of 518 (40.6%) patients were treated with more than one drug and 345 (27.2%) were treated for >7 days. Patients treated for hospital-acquired infections (39.2%) were more likely to receive combinations (47.6% versus 34.4%, P 7 days and did not have any microbiological sample drawn. The time allocated for the survey represented 18.3-25.0 h for 100 patients. CONCLUSIONS: The data provide directions for further interventions, such as better use of diagnostic tools, decreasing the treatment duration and the use of combinations. In addition, the survey shows that, although cumbersome, it is feasible to improve the representativeness of national data in European surveys

    Proposal for shorter antibiotic therapies.

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    Reducing antibiotic consumption has now become a major public health priority. Reducing treatment duration is one of the means to achieve this objective. Guidelines on the therapeutic management of the most frequent infections recommend ranges of treatment duration in the ratio of one to two. The Recommendation Group of the French Infectious Diseases Society (SPILF) was asked to collect literature data to then recommend the shortest treatment durations possible for various infections. Analysis of the literature focused on guidelines published in French and English, supported by a systematic search on PubMed. Articles dating from one year before the guidelines publication to August 31, 2015 were searched on the website. The shortest treatment durations based on the relevant clinical data were suggested for upper and lower respiratory tract infections, central venous catheter-related and uncomplicated primary bacteremia, infective endocarditis, bacterial meningitis, intra-abdominal, urinary tract, upper reproductive tract, bone and joint, skin and soft tissue infections, and febrile neutropenia. Details of analyzed articles were shown in tables. This work stresses the need for new well-conducted studies evaluating treatment durations for some common infections. Following the above-mentioned work focusing on existing literature data, the Recommendation Group of the SPILF suggests specific study proposals
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