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High Temperature - The temperature dependences of the viscosity of liquid Fe90B x Si(10 − x) alloys are studied in the mode of heating and subsequent cooling. The temperature dependences of... 相似文献
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A novel assay based on a nested PCR and restriction enzyme analysis of the PCR products was developed for the rapid detection and identification of Mycobacterium bovis and M. avium-M. intracellulare species in formalin-fixed, paraffin-embedded tissue (PET) specimens. On the basis of the nucleotide sequence data obtained in the present study, general nested primers were constructed to amplify a 424-bp segment of the gene encoding the 65-kDa surface antigen of mycobacteria. The nested PCR assay proved to be highly sensitive, since as little as 5 to 10 fg of extracted mycobacterial DNA was detected. The safety of the assay as a routine method for the diagnosis of M. bovis and M. avium-M. intracellulare in PET specimens was provided by taking various precautions. In order to prevent false positivity, specific tools and procedures were applied. To detect false-negative results and assess the efficiency of the PCR, an internal standard molecule of amplification was constructed. The digestion of the amplicons with the restriction endonuclease Sau96-I allowed the identification of M. bovis and M. avium-M. intracellulare in a large number of clinical specimens. The present results indicate that PCR combined with an internal control of amplification and restriction enzyme analysis of the amplicons provides a rapid, sensitive, and reliable method for routine diagnostic laboratories to detect and identify M. bovis and M. avium-M. intracellulare in PET specimens. 相似文献
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BACKGROUND: With the epidemiological transition phenomenon, Tunisia is now facing the growing prevalence of chronic diseases. Environmental and behavioural changes such as the adoption of new dietary habits and a sedentary lifestyle, and the stress of urbanization and of working conditions all lead to the rise in cardiovascular disease (CVD) risk factors. METHODS: The aim of this study is to estimate the prevalence of the main CVD risk factors in an urban context. For this, we have undertaken a household epidemiological survey of a representative sample of the adult urban population of Soussa, Tunisia (n = 957). RESULTS: This study shows high prevalences of hypertension (blood pressure >160/95 mmHg) of 18.8 per cent with an adjusted rate of 15.6 per cent, history of diabetes of 10.2 per cent, and obesity (body mass index > 30) of 27.7 per cent [significantly higher in women (34.4 per cent)], android obesity 36 per cent, smoking habits 21.5 per cent [significantly higher in men (61.4 per cent)]. CONCLUSION: With this profile of CVD risk factors, Tunisia must implement a national strategy of primary prevention and heart health promotion in addition to the efforts recently made in secondary prevention of some chronic diseases such as hypertension and diabetes. 相似文献
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Creep fracture by slow crack growth is studied in a medium density polyethylene at 60 °C and 80 °C. Whereas elastic-plastic fracture mechanics load parameters fail to provide a unique temperature-independent correlation, that of the fracture mechanics for creeping solids C∗ is proved to be relevant since this parameter correlates very well with the time to failure. Correlation established on both full notched creep tensile and double edge notched tensile tests was validated on cracked gas-pipe samples tested under hydrostatic pressure, extending the use of time to failure versus C∗ diagram to predict lifetime of engineering components. 相似文献
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Gil Francopoulo Nuria Bel Monte George Nicoletta Calzolari Monica Monachini Mandy Pet Claudia Soria 《Language Resources and Evaluation》2009,43(1):57-70
Optimizing the production, maintenance and extension of lexical resources is one the crucial aspects impacting natural language
processing (NLP). A second aspect involves optimizing the process leading to their integration in applications. With this
respect, we believe that a consensual specification on monolingual, bilingual and multilingual lexicons can be a useful aid
for the various NLP actors. Within ISO, one purpose of Lexical Markup Framework (LMF, ISO-24613) is to define a standard for
lexicons that covers multilingual lexical data.
相似文献
Claudia SoriaEmail: |
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A nonlinear model for holographic recording materials is used to evaluate the signal-to-noise ratio in diffuse-object holograms. A comparison of this model with the linear model proposed by Upatnieks and Leonard [J. Opt. Soc. Am. 60, 297 (1970)] shows that our model justifies the experimental results obtained for dieletric holograms at high density before bleaching. 相似文献
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