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The Alderney Race is assumed to have the largest tidal-stream energy potential in the north-western European coastal seas. Interaction of the powerful tidal stream with strong wind, high waves and irregular bathymetry creates hydrodynamic conditions of extreme complexity, with high levels of turbulence. A comprehensive dataset has been created to improve the understanding of physical processes, turbulence, tidal stream and resource variability at the site. The database contains a large amount of oceanographic and meteorological measurements acquired in Alderney Race in 2017-2018. This exceptionally long period of observations (nearly one year) became possible due to modern tools and strategies of data acquisition. The paper presents some significant results from the database analysis. Among many results, we would like to underline the following: (i) a wide range of variability of mean flow and sea state parameters was documented; (ii) exceptionally large values of current velocity (7 m s-1) and significant wave height (8 m) were measured during extreme meteorological conditions; (iii) high-frequency variability of current speed during storm events was also found to be very large, with the standard deviation of velocity reaching 0.3 m s-1 in the bottom boundary layer, and 0.6 m s-1 in the surface layer; and (iv) predominant wind and wave direction relative to the flow impacts the wave height and significantly increases the turbulence kinetic energy of the flow. To our knowledge, this is the largest multi-variable database available on potential tidal energy sites. The results of database analysis can represent a significant advance in environmental conditions and resource characterization and provide advanced information to turbine developers. This article is part of the theme issue 'New insights on tidal dynamics and tidal energy harvesting in the Alderney Race'.
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After becoming a military doctor at the behest of his father, Ronald Ross was destined to make a discovery of paramout importance, i.e., malaria transmission through mosquito bites. This landmark discovery that was the fruit of a combination of curiosity, tenacity and luck, earned him the Nobel Prize in Medicine.
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Premio Nobel , Medicina Tropical/historia , Historia del Siglo XIX , Humanos , India , Malaria/historia , Malaria/prevención & control , Malaria/transmisión , Personal Militar , Mosquiteros/historia , Mosquiteros/estadística & datos numéricos , MédicosRESUMEN
Visceral leishmaniasis is present in 61 countries but 90% of the 500,000 new cases that arise annually occur in five countries, i.e., India, Bangladesh, Nepal, Sudan, and Brazil. Annual mortality is approximately 59000 cases. Agents based on pentavalent antimony have been the mainstay of treatment for the last 60 years. In recent years, however, clinical resistance to these agents has been reported especially in the state of Bihar in India. Pentamidine and amphotericin B were introduced in the 1950s and 1960s. More recent additions to the therapeutic arsenal include liposomal amphotericin B, miltefosine, and paromomycin. Among these recent molecules, miltefosine, i.e., the only oral agent, appears most vulnerable because it involves long-term treatment and has a long half-life. The main therapeutic problems now being encountered are the emergence of acquired resistance to antimonials, the high cost of treatment, and failure of therapy in immunocompromised patients mainly due to concurrent human immunodeficiency virus (HIV) infection. For eradication initiatives such as the one aimed at eliminating leishmaniasis on the Indian subcontinent, the appearance of drug resistance increases the risk associated to parasite infection and, as for malaria, tuberculosis and HIV infection, raises fears that the problems in the implementation of public health policies will lead to highly refractory forms.
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Antiprotozoarios/uso terapéutico , Resistencia a Múltiples Medicamentos , Leishmaniasis Visceral/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Animales , Antiprotozoarios/farmacología , Salud Global , Humanos , Huésped Inmunocomprometido , Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/epidemiologíaRESUMEN
The need for diagnosis of imported malaria is frequent in France. Diagnosis biological tools are different, according methods, sensitivity, interpretation and costs. Strategies for their use could be stratified according locally available methods, and experience of the practician.
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Malaria/diagnóstico , Animales , Antígenos de Protozoos/análisis , Francia , Humanos , Malaria/sangre , Malaria/epidemiología , Malaria/transmisión , Plasmodium , ViajeRESUMEN
Tritium (3H) is mainly released into the environment by nuclear power plants, military nuclear facilities and nuclear reprocessing plants. The construction of new nuclear facilities in the world as well as the evolution of nuclear fuel management might lead to an increase of 3H discharges from the nuclear industry. The VATO project was set up by IRSN (Institut de Radioprotection et de Sûreté Nucléaire) and EDF (Electricité de France) to reduce the uncertainties in the knowledge about transfers of 3H from an atmospheric source (currently releasing HT and HTO) to a grassland ecosystem. A fully instrumented technical platform with specifically designed materials was set up downwind of the AREVA NC La Hague reprocessing plant (Northwest of the France). This study, started in 2013, was conducted in four main steps to provide an hourly data set of 3H concentrations in the environment, adequate to develop and/or validate transfer models. It consisted first in characterizing the physico-chemical forms of 3H present in the air around the plant. Then, 3H transfer kinetics to grass were quantified regarding contributions from various compartments of the environment. For this purpose, an original experimental procedure was provided to take account for biases due to rehydration of freeze-dried samples for the determination of OBT activity concentrations in biological samples. In a third step, the 3H concentrations measured in the air and in rainwater were reconstructed at hourly intervals. Finally, a data processing technique was used to determine the biological half-lives of OBT in grass.
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Contaminantes Radiactivos del Aire/análisis , Pradera , Monitoreo de Radiación , Tritio/análisis , Modelos QuímicosRESUMEN
In this paper, a dynamic compartment model with a high temporal resolution has been investigated to describe tritium transfer in grassland ecosystems exposed to atmospheric 3H releases from nuclear facilities under normal operating or accidental conditions. TOCATTA-χ model belongs to the larger framework of the SYMBIOSE modelling and simulation platform that aims to assess the fate and transport of a wide range of radionuclides in various environmental systems. In this context, the conceptual and mathematical models of TOCATTA-χ have been designed to be relatively simple, minimizing the number of compartments and input parameters required. In the same time, the model achieves a good compromise between easy-to-use (as it is to be used in an operational mode), explicative power and predictive accuracy in various experimental conditions. In the framework of the VATO project, the model has been tested against two-year-long in situ measurements of 3H activity concentration monitored by IRSN in air, groundwater and grass, together with meteorological parameters, on a grass field plot located 2 km downwind of the AREVA NC La Hague nuclear reprocessing plant, as was done in the past for the evaluation of transfer of 14C in grass. By considering fast exchanges at the vegetation-air canopy interface, the model correctly reproduces the observed variability in TFWT activity concentration in grass, which evolves in accordance with spikes in atmospheric HTO activity concentration over the previous 24 h. The average OBT activity concentration in grass is also correctly reproduced. However, the model has to be improved in order to reproduce punctual high concentration of OBT activity, as observed in December 2013. The introduction of another compartment with a fast kinetic (like TFWT) - although outside the model scope - improves the predictions by increasing the correlation coefficient from 0.29 up to 0.56 when it includes this particular point. Further experimental investigation will be undertaken by IRSN and EDF next year to better evaluate (and properly model) other aspects of tritium transfer where knowledge gaps have been identified in both experimental and modelling areas.
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Contaminantes Radiactivos del Aire/análisis , Pradera , Modelos Químicos , Monitoreo de Radiación/métodos , Tritio/análisis , Atmósfera , Plantas , SueloRESUMEN
Zoonosis is the cause of the vast majority of emerging diseases. Bats that occupy the second place in the mammal class play an important role. Whether they belong to the microchiroptera suborder or to the megachiroptera suborder, bats on all five continents have been implicated in transmission of numerous pathogens including not only viruses such as Lyssavirus (e.g. rabies), Hepanivirus (e.g. Hendra and Nipah virus) and recently coronavirus (e.g. SARS-like coronavirus and Ebola virus) but also fungus such as histoplasmosis. By modifying environmental conditions and encroaching on their biotope, human intervention has probably contributed to the introduction of chiropteras into an epidemiologic chain in which they previously had no place, thus promoting the emergence of new pathogens.
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Quirópteros , Vectores de Enfermedades , Zoonosis , Animales , Salud Global , Humanos , Rabia/transmisiónAsunto(s)
Congresos como Asunto , Sociedades Médicas , Humanos , Laos , Saneamiento/normas , Medicina Tropical , Tuberculosis/epidemiologíaRESUMEN
Malaria is a parasitological emergency requiring safe quick accurate diagnosis so that appropriate therapy can be implemented. A number of rapid diagnostic tests based on detection of HRP2 Ag, enzymes, LDH or aldolase are now available. However the use of these tests is restricted to trained, experienced staff in special situations. The purpose of this report is to describe the different tests on the market and clarify the limitations for their use.
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Malaria/diagnóstico , Cromatografía , Humanos , Pruebas Inmunológicas , Factores de TiempoRESUMEN
We report the use of seven acetylaminofluorene (AAF)-labeled DNA probes in evaluating the incidence of various Escherichia coli pathotypes in New Caledonia among 448 children with acute diarrhea (1,278 E. coli pathotypes studied) and 88 controls (264 E. coli pathotypes studied) in 1990. Diarrheogenic E. coli were detected using cloned gene probes for heat-labile and heat-stable enterotoxins, Shiga-like cytotoxins (SLTI and SLTII), the cell invasion phenotype (INV), and enteropathogenic-adherence factor (EAF). Isolates were also studied using bioassays and radioactive DNA probes as reference methods. Enterotoxigenic E. coli (ETEC) were isolated from only 5.36% of the patients; E. coli with localized adherence (LA) to HEp-2 cells was much more common in patients (14.4%) than in controls (3.4%; chi 2 = 7.54, P < 0.01), but most of the E. coli with an LA pattern were members of traditional enteropathogenic E. coli (EPEC) serogroups (chi 2 = 92.95, P < 0.001). Non-enteropathogenic E. coli with an LA pattern were weakly associated with diarrheal disease (8.9%). Escherichia coli with a diffuse or an aggregative pattern did not show a significant association with infantile diarrhea. Eight EPEC serogroups were identified and the frequency of positivity for the LA pattern was 70.5%; the EAF was significantly associated with the 0119:K9 serogroup. No enteroinvasive or SLT-producing E. coli were identified. An evaluation of the AAF probes in comparison with 32P-labeled probes and conventional bioassays was made during this epidemiologic survey. The positive and negative predictive values of the ETEC probes were 0.91 and 1, respectively (overall agreement = 99.8%).(ABSTRACT TRUNCATED AT 250 WORDS)
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Sondas de ADN , Diarrea Infantil/epidemiología , Diarrea/epidemiología , Infecciones por Escherichia coli/epidemiología , Escherichia coli/aislamiento & purificación , 2-Acetilaminofluoreno , Niño , Preescolar , Diarrea/microbiología , Diarrea Infantil/microbiología , Enterotoxinas/biosíntesis , Escherichia coli/genética , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/microbiología , Heces/microbiología , Humanos , Lactante , Nueva Caledonia/epidemiología , Hibridación de Ácido Nucleico , PrevalenciaRESUMEN
As far as transfusions accidents are concerned, immunological causes are frequent. Pretransfusion Bedside Compatibility Tests (PBCT) are the last chance to avoid them. However low data are disponible on the quality their realisation is achieved. The aim of the study is to evaluate the quality level of achievement of these tests, in HIA Laveran Hospital (Marseille Armees, France). During 13 months, from november 2001 to december 2002, we systematically analysed PBCT after use (analysis rate 91%). Three kinds of errors have been noticed: Technical errors, understanding errors and both. Overall mistake rate was 10.4% (1632 tests analysed). In the same time, a complementary formation was dispensed to users responsible of misfits. This formation was successful, decreasing the overall mistake rate from 22.8% (november 2001) to 10.7% (december 2002). This study is an evidence of the importance to evaluate achievement quality of PBCT and shows how efficient can be simple correction methods.
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Incompatibilidad de Grupos Sanguíneos , Transfusión Sanguínea/normas , Sistemas de Atención de Punto/normas , Francia , Humanos , Garantía de la Calidad de Atención de Salud , Reacción a la TransfusiónRESUMEN
A first case of leptospirosis has been recently described in Gabon where bioclimatological characteristics could favour the transmission of that disease. Therefore, a search for antibodies to leptospirae was conducted among 55 military Frenchmen with unexplained fever during a four-month stay in Gabon. Three (5.5%) were positive with IgM levels attesting for recent contamination. A screening antigenic battery identified L. bataviae in two cases and L. sejroe in one case. The three patients were employed outside in the precedent weeks. Travelers are exposed to leptospirosis in numerous Third-World countries. Clinical and biological similarities between leptospirosis and P. falciparum malaria could induce misdiagnosis. Co-infection could also be encountered. Doxycycline, whose activity against P. falciparum is well known, is also effective against leptospirae. Therefore, this drug seems valuable for prophylactic and therapeutic actions in areas exposed to the both diseases.
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Fiebre , Leptospirosis/diagnóstico , Malaria Falciparum , Adolescente , Adulto , Anticuerpos Antibacterianos/sangre , Diagnóstico Diferencial , Francia/etnología , Gabón , Humanos , Inmunoglobulina M/sangre , Leptospira/inmunología , Leptospirosis/inmunología , Masculino , Personal MilitarRESUMEN
All cases of deep mycotic diseases observed between 1975 and 1989 in the Laboratory of Anatomical Pathology at Nouméa's Pasteur Institute have been studied retrospectively together with all available data concerning this pathology both in New Caledonia and the Pacific area. During the period under review, two cases of histoplasmosis, 4 of actinomycosis, 3 sporotrichosis, 5 mycetoma and 5 chromoblastomycosis were recorded in New Caledonia. Clinical and histological data appear to be identical to those observed in other Pacific Islands. Diagnosis is most usually supported only by histological examination and, thus, for future studies it is vital that specific mycologic culture of all cases be carried out.
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Micosis/epidemiología , Actinomicosis/epidemiología , Adolescente , Adulto , Anciano , Cromoblastomicosis/epidemiología , Femenino , Histoplasmosis/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Mucormicosis/epidemiología , Micetoma/epidemiología , Nueva Caledonia/epidemiología , Estudios Retrospectivos , Esporotricosis/epidemiologíaRESUMEN
Chlamydia trachomatis was researched from 400 pregnant women. 76 of them were found infected and 129 carried serological signs of infection. We purpose a detection at the end of pregnancy interesting women with sexually transmitted diseases background and those with serological positive results (greater than 1/64). Then, treatment of the mother will be an useful method of prevention against neonatal infection.
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Infecciones por Chlamydia/epidemiología , Chlamydia trachomatis , Complicaciones Infecciosas del Embarazo/epidemiología , Adulto , Femenino , Humanos , Nueva Caledonia/epidemiología , Embarazo , PrevalenciaRESUMEN
Dengue is a frequent viral infection in the intertropical countries. The frequency and the severe forms of this infection are a real problem of public health. The haemorrhagic forms of the disease are constantly associated with thrombocytopenia. Its pathophysiology is still unclear. Among the different hypothesis, immune mechanisms play the main role. The authors discussed here the responsibility of the binding of immune complexes and the role of cytokines.
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Dengue/complicaciones , Hemorragia/complicaciones , Trombocitopenia/etiología , Complejo Antígeno-Anticuerpo , Citocinas/fisiología , Humanos , Trombocitopenia/inmunologíaRESUMEN
When two cholera epidemics broke out in Djibouti, respectively in 1993 and 1994, Bioforce was obliged to intervene. The first time, three goals were pursued: setting up a rehydration centre in a tent, organizing epidemiological surveillance and training local personnel in treatment and diagnosis techniques. The next year, the epidemic followed serious flooding. The epidemiological analysis showed that cholera had become endemic in the poor neighbourhoods of the town and that epidemic break-outs were favoured by contaminated surface water and disturbances in the distribution of drinking water. The epidemic of 1997, likewise following flooding, only confirmed this point of view.
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Cólera/historia , Brotes de Enfermedades/historia , Cólera/diagnóstico , Cólera/epidemiología , Cólera/prevención & control , Desastres , Djibouti/epidemiología , Enfermedades Endémicas , Métodos Epidemiológicos , Fluidoterapia , Historia del Siglo XX , Humanos , Microbiología del Agua , Abastecimiento de AguaRESUMEN
A sero-epidemiological survey was conducted on Wallis Island, in the South Pacific, from July 1988 to May 1989. A random sample from the general population was examined. 672 sera were tested for HBs antigen and anti-HBc antibody. Analysis of the data showed that there was little, if any, transmission from mother to newborn; serological markers seemed to be acquired during the first years of life, before the age of 15 years. After 15 years, seropositivity rate is stabilized at 85% for one and/or the other of the two markers. The seropositivity rate is 39% for the HBs antigen alone. A protocol to vaccinate infants less than one year is proposed.
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Hepatitis B/epidemiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Hepatitis B/transmisión , Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/sangre , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Islas del Pacífico/epidemiología , EmbarazoRESUMEN
The authors report a case of severe, life-threatening, meningo-encephalitis occurring in a young nonimmunodepressed adult with varicella. The demonstration of a cytopathogenetic effect of his cerebrospinal fluid and of immunoglobulins M specific to the varicella-zoster virus was in favour of an acute, directly viral-dependent encephalitis rather than an immune-mediated leucoencephalitis, as used to be commonly admitted. This is an incitement to use acyclovir in such cases, the effect of which contributes to reinforce this pathogenic hypothesis.
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Herpesvirus Humano 3/aislamiento & purificación , Meningoencefalitis/líquido cefalorraquídeo , Adulto , Varicela/complicaciones , Humanos , Masculino , Meningoencefalitis/etiología , Meningoencefalitis/microbiologíaRESUMEN
OBJECTIVE: The aim of this study, conducted in the French Military hospitals, was to monitor the course of the antimicrobial sensibility of bacteria isolated from nosocomial infection in intensive care units. PATIENTS AND METHODS: A prospective study has been conducted from January to December 1998 in all the intensive care units of the French Army. All the non-repetitive strains isolated from nosocomial infection were collected and sent to a reference centre. Antimicrobial susceptibility was determined by the agar dilution method. Beta-lactamase were identified by iso-electro-focalisation. Antibiotics choice and interpretative criteria were those of the "Comité Français de l'Antibiogramme de la Société Française de Microbiologie". RESULTS: A total of 849 strains are included in this study. Pseudomonas aeruginosa was the most frequently isolated bacterium (20%) followed by Escherichia coli (19%) Staphylococcus aureus (15%), coagulase-negative Staphylococci (CoNS) (11%) and Enterococci (7%). Imipenem was the most effective antibiotic against enterobacteriaceae (336 isolates; 100% susceptibility). Gentamicin (92%), amikacin (92%) third generation cephalosporins (83%), aztreonam (83%) and ciprofloxacin (78%) were also very effective. Resistance to III generation cephalosporins was correlated with an extended spectrum beta-lactamase (BLSE) in 36% of cases. This BLSE could be associated with an over production of the constitutive cephalosporinase. The most frequent species producing BLSE were Enterobacter aerogenes (75% of BLSE) and Klebsiella pneumoniae (17%). Among the 172 P. aeruginosa isolated, antimicrobial susceptibility were respectively: 71% for imipenem, 62%: tobramycin, 60%: amikacin 59%: ciprofloxacin 59% piperacillin + tazobactam, 55% piperacillin, 53%: ceftazidime and 44% for ticarcillin. Seventy per cent of the 96 CoNS and 50.2% of the 126 S. aureus isolated were resistant to methicillin. A strain of S. aureus and 2 CoNS strains had intermediate resistance to teicoplanin. Twenty per cent of the 59 Enterococci strains isolated were resistant to aminopenicillins (10/11 strains of E. faecium), and 9% presented a high level of resistance to gentamicine. One strain of E. faecium was resistant to vancomycin. CONCLUSION: The evolution of the susceptibility to antibiotics in intensive care units reflects the antibiotic pressure and level of cross-transmission. High rates of meticillin-resistance among staphylococci, of resistance to beta-lactams antibiotics among P. aeruginosa and of ciprofloxacin among Enterobacteriaceae are shown in this study. The implementation of appropriate strategies for surveillance and prevention is necessary.
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Infecciones Bacterianas/tratamiento farmacológico , Infección Hospitalaria/tratamiento farmacológico , Farmacorresistencia Microbiana , Infecciones Bacterianas/microbiología , Infección Hospitalaria/microbiología , Relación Dosis-Respuesta a Droga , Enterobacteriaceae/efectos de los fármacos , Enterococcus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Francia , Hospitales Militares , Humanos , Unidades de Cuidados Intensivos , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacosRESUMEN
OBJECTIVES: Monitor the evolution in France of antibiotic sensitivity of non-typhoid salmonella isolated in fecal cultures conducted in army hospital laboratories. METHODS: A prospective study was performed from January 1998 to December 1999 in all the biology departments of the 11 army hospitals in France. All the non-repetitive strains were sent to an official center for serotyping and determination of the minimum inhibiting concentrations, by dilution in Mueller Hinton's gelose. The antibiotics currently used in treatment were tested and interpretation endpoints followed the recent recommendations of the Antibiogram committee of the French society of microbiology. Identification of beta-lactamase was conducted by iso-electric focalization and polymerization by chain reaction (PCR). For Salmonella Typhimurium, research for the specific resistance locus of the DT104 clone was made using PCR. RESULTS: Two hundred and twenty-two non-repetitive salmonella strains were isolated. The principle serotypes found were: Salmonella Enterididis (23.9%), S. Typhimurium (21.2%) and S. Hadar (10.8%). All the strains were sensitive to ciprofloxacin and cefotaxim, whereas one third exhibited reduced sensitivity to aminopenicillin. Depending on the serotype, Typhimurium and Hadar serotypes exhibited significantly lesser sensitivity to aminopenicillin, nalidixic acid and tetracycline. For S. Typhimurium, resistance is related to the diffusion of the multiresistant DT104 clone, which involves half of the strains of this serotype. For S. Hadar, 18 out of 24 strains (75%) were resistance to nalidixic acid, and 5 of them exhibited reduced resistance to ciprofloxacin. There was no difference in sensitivity to antibiotics between the strains responsible for diarrhea and those isolated in systematic examinations for capacity to work in the food trade (respectively 54 and 46% of strains). CONCLUSION: Non-typhoid salmonella are frequently isolated in diarrhea of infectious origin. The increasing resistance to antibiotics is primarily related to the diffusion of the DT104 clone, regarding S. Typhimurium and to the increase in resistance to quinolone, regarding S. Hadar.