A simple method for energy calibration of keV incident electron beam using a contactless electrostatic voltmeter probe.

A simple method is proposed to calibrate the energy of an electron beam. An electrical floating metal foil is irradiated by the incident electrons. The electron energy is deduced from the magnitude of the surface potential developed on the irradiated conductor surface. The measurement of the surface potential is made outside the vacuum chamber on a metallic slab connected through a coaxial feedthrough to the electron irradiated sample. The energy calibration obtained by this method is compared to the conventional method based on measuring the energy position of the backscattered electron elastic peak.

An epidemiological study of sheep pox in Tunisia (2008-2017).

Sheep pox is a highly contagious disease causing significant economic losses on livestock farms, especially among young animals. Epidemiological analysis of retrospective data on sheep pox surveillance over ten years revealed the endemicity of the disease in Tunisia. Temporally, the prevalence of infected farms increased during the last five years analysed (2013-2017), despite control measures for the disease, which are based essentially on vaccination. Analysis of the seasonality of infection showed that most outbreaks occurred in autumn and winter. The geographical distribution and spatial analyses classified the governorate of Sidi Bouzid as the area most affected by sheep pox duringthe period of study. It was observed that vaccination coverage decreasedbelow the recommended value (80%) in the last four years (2013-2016).

La clavelée est une maladie extrêmement contagieuse qui se traduit par d'importantes pertes économiques dans les élevages, les jeunes ovins étant les plus touchés. Une analyse épidémiologique rétrospective des données recueillies sur la clavelée, au cours d'une période de dix ans, a révélé que la maladie est présente à l'état endémique en Tunisie. Les données temporelles ont fait ressortir une prévalence accrue des élevages infectés au cours des cinq dernières années de la période d'étude (2013-2017), malgré les mesures de lutte appliquées contre la maladie, essentiellement la vaccination. L'analyse de la saisonnalité de l'infection a montré que la plupart des foyers se déclaraient en automne et en hiver. Les données spatiales relatives à la distribution géographique des foyers ont révélé que le gouvernorat de Sidi Bouzid était la zone la plus affectée par la clavelée pendant la période étudiée. Il a été constaté que la couverture vaccinale est passée en dessous du seuil recommandé (80 %) au cours des quatre dernières années de l'étude (2013-2016).

La viruela ovina es una enfermedad muy contagiosa que afecta especialmente a los animales jóvenes y causa importantes pérdidas económicas en las explotaciones de producción pecuaria. El análisis epidemiológico retrospectivo de los datos de vigilancia de la viruela ovina correspondientes a diez años reveló que la enfermedad reviste carácter endémico en Túnez. Por lo que respecta a la secuencia temporal, la prevalencia de explotaciones infectadas aumentó en el curso de los cinco últimos años analizados (2013-2017) pese a las medidas instauradas para combatir la enfermedad, basadas esencialmente en la vacunación. El análisis de la estacionalidad de la infección puso de manifiesto que la mayoría de los brotes se declaraban en otoño e invierno. A tenor del análisis espacial y de la distribución geográfica, la zona más afectada por la viruela ovina durante el período de estudio fue la prefectura de Sidi Bouzid. Se observó asimismo que en los últimos cuatro años (2013-2016) la cobertura de vacunación descendió por debajo del valor recomendado (un 80%).

[Cardiac troponin I and the post-mortem diagnosis of myocardial damage]. / Intérêt du dosage post-mortem des troponines I cardiaques dans l'identification des lésions myocardiques.

UNLABELLED: The aim of this study is to analyse the diagnostic efficacy of post-mortem dosage of cardiac troponine I in cadaver fluids in detection of myocardial damage. MATERIAL AND METHODS: Our study is prospective, interesting 72 corps autopsied at the Department of Forensic Medicine of the University Hospital Fattouma Bourguiba of Monastir-Tunisia. Were excluded from the study, resuscitated cases and those examined more than 48h after death. Levels of cardiac troponine I were measured in pericardial fluid, cardiac blood and peripheral blood. Statically significant correlations between different variables levels of cardiac troponine I and cardiac damage were studied. Receiver-operator characteristic (ROC) curves were generated and areas under the curves were determined. SPSS (version 12.0) et MedCalc statistical software (version 11.0) were used for statistical analysis. Results were considered to be statistically significant when P<0.05. MAIN RESULTS: Cardiac troponin I levels in pericardial fluid, cardiac and peripheral blood are correlated significantly between subject with and without observable signs of myocardial damage with a P value respectively at 0.0007, 0.0009 and 0.004. ROC curves analysis showed that the pericardial fluid have the best sensibility and specificity with a cut-off level at 108ng/ml and an area under the curve at 0.925. CONCLUSION: Our data indicate that cardiac troponin I may be a powerful aid in the diagnosis of myocardial damages. This biological test can be used in triaging sudden deaths before to external examination versus complete autopsy.

An anomalous contrast in scanning electron microscopy of insulators: the pseudo-mirror effect.

In a scanning electron microscope, electron-beam irradiation of insulators may induce a strong electric field due to the trapping of charges within the specimen interaction volume. On one hand, this field modifies the trajectories of the beam of electrons subsequently entering the specimen, resulting in reduced penetration depth into the bulk specimen. On the other hand, it leads to the acceleration in the vacuum of the emitted secondary electrons (SE) and also to a strong distortion of their angular distribution. Among others, the consequences concern an anomalous contrast in the SE image. This contrast is due to the so-called pseudo-mirror effect. The aim of this work is first to report the observation of this anomalous contrast, then to give an explanation of this effect, and finally to discuss the factors affecting it. Practical consequences such as contrast interpretations will be highlighted.

Cardiac operations during active endocarditis.

Between December 1982 and March 1990, 65 patients with active infective endocarditis underwent cardiac operations. Their mean age was 28.6 years (range 1 to 65 years). The most common infecting organisms were staphylococcus (33.8%), streptococcus (18.5%), and brucella (16.9%); 11 patients (16.9%) had cultures negative for infection. A rheumatic, native valve, most commonly the aortic, was involved in 40 patients, a prosthetic valve (with the mitral most common) in 18 patients, and in seven patients the infection involved a congenitally abnormal valve. Aortic root abscess developed in 21.5% of patients. In 30 patients operation was performed within 3 days of the start of intravenous antibiotic therapy, usually within 3 days of admission (group A); this resulted in fewer preoperative complications and a significantly lower postoperative complication rate than in those 35 patients who underwent operations more than 3 days after starting antibiotic therapy (group B). Preoperative embolic phenomena occurred in eight (12.3%) of the 31 patients who had large, mobile vegetations (2/16 [12.5%] in group A and 6/15 [40%] in group B). Overall there was no reinfection. No postoperative paravalvular leaks developed in group A. Nine patients died in the hospital (13.8%) (four in group A and five in group B); in all patients the infecting organism was staphylococcal or fungal. There was one late death. Early operation should always be considered in active infective endocarditis, especially when a prosthetic valve is involved or the infecting organism is staphylococcal or fungal. The disclosure of moderate to large vegetations by two-dimensional echocardiography is an indication for operation.

Fixed drug eruption due to cotrimoxazole.

Drug eruptions are among the most common cutaneous disorders encountered by dermatologists. They occur in many forms and mimic many dermatoses. Fixed Drug Eruption (FDE) has its own characteristics and may be associated with ingestion of a number of agents. The incidence of FDE induced by a specific drug depends on the frequency with which the agent is used in a given part of the world. Recently we have encountered many cases of FDE due to Cotrimoxazole.

Pediculosis capitis in Benghazi, Libya. A school survey.

A school survey of pediculosis capitis in Benghazi, Libya, revealed an alarmingly high prevalence of 78.6%. The percentage of infestation was 67.2% for boys and 88.1% for girls. It was more frequent in schools located in rural areas (85.55%) as compared with those in urban areas (44.28%). There was no significant difference in infestation in younger and older children of either sex. Besides other factors for such a high prevalence, the lack of health education of family members may play a crucial role in transference and louse infestation.

Ninety-eight fixed drug eruptions with provocation tests.

Ninety-eight patients having fixed drug eruptions were subjected to provocation tests. Cutaneous involvement was seen in 43, mucous membrane in 33 patients, while cutaneous and mucous membrane involvement was seen in 22 patients. The causative drugs were found to be trimethoprim-sulphamethoxazole (45), acetylsalicylic acid (24), hyoscine butylbromide (Buscopan) (8), ibuprofen (Brufen) (6), oxyphenbutazone (6), tetracycline hydrochloride (2), phenolphthalein (1) and phenobarbitone (1). There was evidence of cross-sensitivity between oxyphenbutazone and phenylbutazone.