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Polymer bounded explosives (PBXs) consist of energetic crystals coated with a polymer binder. These materials exhibit a highly heterogeneous microstructure. The initiation of the detonation phenomenon in PBXs is believed to be generated at the microstructure scale through hotspots. Hence, many of the explosives properties (initiation, desensitization, etc.) are understood as a direct consequence of their microstructure. Mesoscale modeling directly addresses the physics of hotspot formation. Unfortunately, high computational cost prevents their use on laboratory-sized and large scale experiments. In practice, continuum-scale models remain mandatory. We describe a new reactive burn model, named WGT, aiming to represent, at the continuum scale, some of the complexity of the PBX's microstructure. The initiation regime is driven by the shock temperature and results from surrogate modeling of the kinetics of a heterogeneous nucleation and growth model. The other regimes follow the formulation of the WHS2D2 reactive burn model and are driven by the local temperature. This model was calibrated on experimental results for PBX 9502 available in the literature, such as detonation velocity–curvature laws, Pop-plot data, or embedded electromagnetic particle velocity gauges. The model was also tested against desensitization and propagation data. [ABSTRACT FROM AUTHOR]

In this paper, computations of gaseous detonations in several configurations are performed and discussed. The objective is to investigate the detonation characteristics, specially the influence of losses, through a quantitative analysis of the mean hydrodynamic structure. The results are divided into two parts: The first one relates to the propagation of ideal detonations without losses and to their characterization for a specific set of thermodynamic parameters, and the second part investigates the influence of losses on the averaged hydrodynamic structure of detonations. This is achieved by means of a specific and canonical configuration, in which a detonation wave propagates in a reactive layer bounded by an inert gas. This topology is investigated through a comparison of the instantaneous flow-field, cellular structure, and averaged quantities such as the mean curvature and the hydrodynamic thickness. This configuration may be regarded as non-ideal, as the detonation experiences losses due to the expansion of the detonation products toward the inert layer. The prediction of the detonation characteristics, as well as the conditions at which quenching occurs, remains a challenge when losses are involved. The main objective is to assess to what extent the hydrodynamic thickness can be used as a relevant length scale in the analysis of the resulting database. The results also highlight the key features of this configuration, which isolates a specific issue related to the rotating detonation engines. The temperature of the inert layer strongly affects the structure of the detonation–shock combined wave. For a high-temperature inert gas confinement, a detached shock appears in the upper layer and a jet of fresh mixture develops downstream of the front. For this condition, we observed a reduction in the critical dimensions by a factor of two. The degree of regularity of the detonation structure, from weakly unstable to mildly unstable cases, through the variation of the reduced activation energy, was investigated. The hydrodynamic thickness appears to be a useful characteristic length scale for the detonation, as it allows a better analysis of the results and a scaling of data. Moreover, the detonation velocity deficit can be globally expressed as a function of the ratio of the hydrodynamic thickness to the mean radius of curvature at the bottom of the wall. [ABSTRACT FROM AUTHOR]

Aim: Assessing acceptance of controlled drinking (CD) among French alcohol specialists. Methods: On-line survey of 547 French alcohol specialists. We searched factors associated with acceptance of CD, and factors that affected the specialists' selection of treatment goal. Criteria for success used by specialists in clinical practice were compared with criteria expected to be used in clinical trials. Results: CD was accepted as a treatment goal by 48.6% of alcohol specialists (n = 105, n = 216), and 61.9% practiced CD for their own patients (n = 130, n = 210). Factors in selecting outcome goals were: patient's choice, perceived self-efficacy, relapse history and severity of dependence. Age, profession and basis of specialists' opinion on CD were associated with acceptance of CD. Conclusion: Half of French alcohol specialists accept CD as a goal. Acceptance was associated with specialists' personal and professional characteristics. The criteria for success specialists use in their clinical practice differ from those they expect to be used in clinical trials. [ABSTRACT FROM PUBLISHER]

Aim: Assessing acceptance of controlled drinking (CD) among French alcohol specialists. Methods: On-line survey of 547 French alcohol specialists. We searched factors associated with acceptance of CD, and factors that affected the specialists' selection of treatment goal. Criteria for success used by specialists in clinical practice were compared with criteria expected to be used in clinical trials. Results: CD was accepted as a treatment goal by 48.6% of alcohol specialists (n = 105, n = 216), and 61.9% practiced CD for their own patients (n = 130, n = 210). Factors in selecting outcome goals were: patient's choice, perceived self-efficacy, relapse history and severity of dependence. Age, profession and basis of specialists' opinion on CD were associated with acceptance of CD. Conclusion: Half of French alcohol specialists accept CD as a goal. Acceptance was associated with specialists' personal and professional characteristics. The criteria for success specialists use in their clinical practice differ from those they expect to be used in clinical trials. [ABSTRACT FROM AUTHOR]

Background: Although the use of cannabis among young people has become a major public health concern, there is no such test in France for general population surveys. Objective: This article aims to present a short screening test for cannabis abuse among adolescents and young adults in general population surveys, the CAST (Cannabis Abuse Screening Test) designed at the French Monitoring Center for Drug and Drug addictions (OFDT). Methods: The survey was conducted in France among 1728 scholars aged 14-22, in secondary schools, high schools, and university. After presenting internal consistency and factorial structure, the authors compared the CAST with the part of the POSIT (Problem-Oriented Screening Instrument for Teenagers) dealing with alcohol and drug abuse among cannabis users in order to validate the optimal thresholds of the CAST for the high risk of abuse defined for the POSIT. Results: The CAST appears to be unidimensional and have high internal consistency (Cronbach's alpha equals 0.81). Among cannabis users whoa are low alcohol consumers, CAST presents very high sensitivity and specificity compared with the POSIT (respectively, 93 and 81%). Conclusions: The CAST seems to be an efficient tool in order to screen for cannabis use disorders among adolescents and young adults. Further research is needed to confirm this result. [ABSTRACT FROM AUTHOR]

Numerous symptoms in psychiatry are subjective (e.g., sadness, anxiety, craving or fatigue), fluctuate and are environment dependent. Accurate measurement of these phenomena requires repeated measures, and ideally needs to be performed in the patient's natural environment rather than in an artificial laboratory environment or a protected hospital environment. The usual paper and pencil questionnaires do not meet these two conditions for reasons of logistics. A recently developed method, ecological momentary assessment (EMA), made it possible to implement these field assessments via ingenious use of various devices (most frequently an electronic diary) coupling an auditory signal with computerized data capture. The subject carries the device with him/her at all times, and data is recorded in vivo in real time. The programming of repeated measures in the form of a Likert scale or pull-down menu is easily achieved. A recall alarm system can help increase compliance. Compared with classical self-report, EMA improves the validity of the assessment of certain symptoms, which are the main evaluation criteria in clinical trials concerning certain pathologies (e.g., craving and treatment of addiction), where measurement was previously liable to bias. This article sets out to present this method, its advantages and disadvantages, and the interest it presents in psychiatry, in particular via three original applications developed by the authors including: measurement of reaction time without the knowledge of the subject in order to test certain cognitive models; use of a graphic solution for the data recorded for functional analysis of disorders; and the use of data collection via mobile phone and text messages, which also enables therapeutic interventions in real time by text messages, personalized on the basis of the situational data collected (e.g., in the case of craving, the associated mood, solitary or group consumption or concomitant occupations). [ABSTRACT FROM AUTHOR]

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BACKGROUND: To study cognitive interference associated with craving for alcohol, the Ecological Momentary Assessment (EMA) method was used to measure the relationship between craving and reaction time. A secondary aim was the study of the predictive factors for craving during alcohol detoxification. The EMA enables both repeated measures of craving in a natural setting and the recording of reaction time without the patient being aware of this. METHODS: Craving for alcohol, reaction time, sadness and anxiety were recorded 8 to 12 times a day, over three weeks of detoxification in 14 alcoholics (n=1767 measures), on an electronic diary issuing random prompts. Mixed models were used for statistical analysis (alpha=5%, 1-beta=88%). RESULTS: Reaction time was significantly increased in univariate analysis when a craving episode occurred but this difference did not persist after multivariate analysis. Craving episodes were more frequent and intense than previously reported. Predictive factors of craving during detoxification were: age, gender, sadness, anxiety and the number of previous detoxifications. Antidepressants, anti-craving medications but not benzodiazepines were negatively associated to craving. [ABSTRACT FROM AUTHOR]

BACKGROUND: Carbohydrate-deficient transferrin (CDT) and gamma-glutamyl transferase (GGT) are used as biomarkers of alcohol misuse. The aim of this study was to evaluate, in terms of sensitivity and specificity, the performance of the new Bio-Rad %CDT TIA kit and GGT assay for identifying alcohol abuse and alcohol dependence (according to the DSM-IV criteria). METHODS: An open multicenter study (30 centers) over 3 months, including patient groups of 'abusers,' 'dependents,' and controls, was conducted in France. RESULTS: In alcohol abuse, the sensitivity of GGT was 0.56, and that of CDT was 0.80; in alcohol dependence, the sensitivity of GGT was 0.86, and that of CDT was 0.91. The specificity of GGT was 0.77, and that of CDT was 0.83. The association of GGT with CDT increased sensitivity for alcohol abuse to 0.90 and for alcohol dependence to 0.99, but it appreciably decreased specificity (0.63). CONCLUSIONS: %CDT is the better screening marker for alcohol abuse and dependence, but GGT is still a useful marker for the detection of alcohol dependence. As an assay method, the second-generation Bio-Rad %CDT immunoassay can be recommended for routine CDT measurement. [ABSTRACT FROM AUTHOR]

Hybridization and introgression are important natural evolutionary processes that can be successfully investigated using molecular markers and open- and controlled-pollinated progeny. In this study, we collected open-pollinated seeds from Cedrus atlantica, Cedrus libani and C. libani × C. atlantica hybrids from three French-plantation forests. We also used pollen from C. libani and Cedrus brevifolia to pollinate C. atlantica trees. The progeny were analyzed using three different types of molecular markers: RAPDs, AFLPs and cpSSRs. Chloroplast DNA was found to be paternally inherited in Cedrus from the progeny of controlled-crosses. Heteroplasmy, although possible, could not be undoubtedly detected. There was no indication of strong reproductive isolating barriers among the three Mediterranean Cedrus taxa. Gene flow between C. atlantica and C. libani accounted for 67 to 81% of viable open-pollinated seedlings in two plantation forests. We propose that Mediterranean Cedrus taxa should be considered as units of a single collective species comprising two regional groups, North Africa and the Middle East. We recommend the use of cpSSRs for monitoring gene flow between taxa in plantation forests, especially in areas where garden specimens of one species are planted in the vicinity of selected seed-stands and gene-conservation reserves of another species. [ABSTRACT FROM AUTHOR]

BACKGROUND: General medical practitioners are essential for the prevention, diagnosis, and management of alcohol use disorders. Studies to examine medical practice in this field, however, are very rare. METHOD: A cross-sectional study involving 2010 patients seen by a sample of 145 general practitioners in the Auvergne region of central France was conducted on a given day in May 1998. The purpose of the study was to evaluate the prevalence of alcohol use disorders (using the DSM-IV diagnostic criteria for alcohol abuse or dependence and the CAGE questionnaire) and so to estimate the proportion of nonsomatic alcohol-related care dispensed. RESULTS: Sixteen percent of patients consulting their general practitioner had an alcohol problem, 27% of men and 5% of women. On average, a quarter of these patients had not been previously identified by the physician. Diagnosis seemed particularly difficult in women: 11% of women aged between 36 and 45 had an alcohol-related problem that went unidentified in 60% of cases. Care for alcohol-related health problems was therefore seriously inadequate. In one third of cases, patients with a diagnosed alcohol-related problem were not followed up by the physician for that problem. Two thirds received no medication, and in more than 80% of cases the physician did not refer to a specialist or prescribe admission to a specialized hospital ward. CONCLUSIONS: These results underline the diagnostic and therapeutic difficulties experienced by general practitioners. This study has led to the establishment of a pilot health care network for patients suffering from alcohol use disorders. This network involves voluntary doctors who have been trained and are better paid for their services. Care protocols have been established to which these practitioners have to adhere. [ABSTRACT FROM AUTHOR]

— The health costs of alcohol-related problems in France were estimated using two cost evaluation approaches: (1) estimate based on the proportion of cases attributable to alcohol abuse (the alcohol abuse factor); (2) estimate based on prevalence of alcohol abuse for in- and out-patients. For a 10% prevalence of alcohol abuse in the general population, the minimum cost in 1996 was about US$ 2300 million; for a prevalence of 15% it was US$ 2700 million. This cost concerns the health disorders that are linked directly or indirectly to alcohol abuse. It did not allow for injuries from accidents caused by alcohol intoxication and undervalued the cost of out-patient care. Based on the prevalence of alcohol-related disorders seen at hospitals, a percentage of the total in-patient and out-patient costs due to effects of alcohol could be estimated. However, this did not permit an estimate of the cost of care in which alcohol abuse was a risk factor only. Based on the available data showing that between 3% and 10% of inpatients have a directly alcohol-related condition, estimates of in-patient treatment costs varied from US$ 1300 to 2100 million. Among adult out-patients, 20% present with a disorder in which alcohol is a factor or suffer from an alcohol-related illness, which corresponds to a cost of about US$ 1600 million. Thus, these methods yield minimum year's cost estimated between US$ 2500 and 3300 million. These costs are high, compared to the low level of financing for the specialized facilities offering treatment to people in difficulty due to alcohol excess, which was US$ 23 million in that year. As regards social and total costs, estimates from four Western countries have found that about 75% of the total costs of alcohol abuse was attributable to social harm, and 25% to medical costs. Applying this ratio to the French data gives an estimated total cost to French society of about US$ 13 200 million, i.e. 1.04% of the gross national product. [ABSTRACT FROM PUBLISHER]

The prevalence of alcohol use disorders in hospital patients was studied in all the hospitals of one area of France. Alcohol disorders were diagnosed by the head nurse or a physician in the hospital where the patient was being attended, and by means of the CAGE self-questionnaire This descriptive survey, carried out on one particular day, concerned 7626 patients. The prevalence of alcohol disorders was 18%, whereas only 6% of the admissions were for alcohol-related pathologies. Prevalences were 25% in men and 7% in women, 10% in persons aged under 25 years and 43% in men aged between 36 and 55 years. In all, one patient in two was diagnosed directly, though only one in four in the age range under 25 years. These results suggest that too few patients with alcohol use disorders are identified in hospitals, especially in certain age groups and certain types of ward [ABSTRACT FROM PUBLISHER]

X-linked hydrocephalus-stenosis of the aqueduct of Sylvius sequence (H-SAS, MIM number 30007) is a rare genetic disorder characterized by hydrocephalus, macrocephaly, adducted thumbs, spasticity, agenesis of corpus callosum and mental retardation. We confirm here the localisation of the mutant gene on Xq (Xq 2.8) by linkage analysis in a 5-generation pedigree (maximum lod score of Z = 4.57 at theta = 0.04 with probe St14 at locus DXS52) and emphasise the phenotypic variability of the disease. Ventricular dilatation in affected males was either severe and diagnosed antenatally or moderate and consistent with a long survival with little or no macrocephaly. Since other X-linked syndromes of mental retardation with spasticity and flexion deformities of the thumbs have previously been shown to map to the Xq 2.8 region as well (e.g. MASA syndrome and spastic paraplegia), the present results raise the question of whether H-SAS syndrome, MASA syndrome and spastic paraplegia with mental retardation might represent different phenotypic expression of various mutations at the same locus. [ABSTRACT FROM AUTHOR]

Theophylline levels in plasma, erythrocytes and cantharides-induced blister fluid (BF) have been correlated with peak expiratory flow (PEF) in asthmatic patients. Nine asthmatic men received an IV infusion of 240 mg theophylline at a constant rate for 30 min. The theophylline concentrations in erythrocytes and blister fluid were 37 % and 78 % of those in plasma. There was not a strong correlation between erythrocyte or blister fluid penetration and the clinical effect of theophylline. [ABSTRACT FROM AUTHOR]