检索结果-南通市图书馆

Production threshold impact on a GEANT4 calculation of the power deposition in a fast domain: MEGAPIE spallation target

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2019年第5期30卷 40-47页

作者： abdesslam Lamrabet Abdelmajid Maghnouj Jaouad Tajmouati Mohamed Bencheikh Laboratory of Integration of Systems and Advanced Technologies Faculty of Sciences Dhar El mahrazUniversity Sidi Mohamed Ben Abdellah El Hajeb

The calculation time in the Monte Carlo simulations consistently represents an essential issue. It is often very long, and its decrease constitutes a challenge for the simulator. Generally, an MC simulation is qualified as quality or not according to two main criteria: the calculation time and the accuracy of the results. However, in most cases, the optimization of one criterion affects negatively the other. Therefore, a compromise between both of them is always required in this kind of simulation. The present work aims at studying the impact of the production threshold(or cut) of the GEANT4 toolkit on the calculation of the power deposition in the MEGAPIE spallation *** production threshold of secondaries is a GEANT4 intrinsic parameter. It indicates the limit of energy we can reach in the production of secondary particles. This study has allowed us to make the following conclusions. First,the influence of the cut on the calculation of the deposited power depends on the volume size, its arrangement and the importance of the electromagnetic processes occurring within. Second, the accuracy of the calculations can be acceptable only below a given value of the cut ***, this accuracy remains almost unchangeable from a certain value of the cut. The study has also made it possible to explore the prevalence of certain interactions in the zone of spallation in the MEGAPIE target.

关键词： Production threshold Power deposition Spallation MEGAPIE GEANT4

Spatial and temporal spread of Citrus tristeza virus and its aphid vectors in the North western area of Morocco

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Insect Science 2016年第6期23卷 903-912页

作者： abdesslam Elhaddad Amal ElAmrani Alberto Fereres Aranzazu Moreno Faculty of Science and Technics of Tangier Abdelmalek Essaadi University Morocco- Ancienne Route de I'Aeroport Km 10 Ziaten. BP:416 Tanger Morocco Instituto de Ciencias Agrarias Consejo Superior de Investigaciones Cientificas (ICA-CSIC) CISerrano 115 dpdo. 28006 Madrid Spain

First report of Citrus tristeza virus （CTV, Closterovirus） in Morocco datesback to 1961 in collections of citrus varieties. An exhaustive survey of citrus in the north of the country in 2009 revealed that CTV was spread all over the citrus production area. We attempted to evaluate the relative contribution of different aphid species in the spread of CTV disease in a Citrus reticulata orchard at the Loukkous region during 2 years （2012 and 2013）. The overall CTV incidence estimated in the experimental site increased from 17.8% in 2012 to 31.15% in 2013. The most abundant aphid species colonising clementine trees was Aphis spiraecola and A. gossypii. Both aphid species reached their maximum peaks during the spring season. The rate of viruliferous aphids, estimated by real-time RT-PCR of single aphid, revealed that 35.4% of winged A. gossypii and 28.8% of winged A. spiraecola were viruliferous, confirming a high inoculum pressure in the area surrounding the experimental site. The aphid species Toxoptera citricida, which is able to transmit the aggressive isolates of CTV, was not found in the Loukkous region. The study of the spatial distribution of the CTV showed that in general, the disease was randomly distributed in the field. Overall, the results seem to indicate that A. spiraecola may be considered as the major aphid species contributing to CTV spread in our experimental conditions. The prevalence of mild strains in the region and the high level of aphid flight activity could explain the rapid evolution of CTV incidence in the experimental area.

关键词： aphids Aphis gossypii Aphis spiraecola citrus Citrus tristeza virus spatial distribution

Cervix and breast cancers in Oujda city in Eastern Morocco: Determinants and risk factors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Preventive Medicine 2012年第1期2卷 9-15页

作者： Abdellatif Maamri Mohamed El Hfid Abdelhafid Chafi abdesslam Boutayeb Department of Biology Faculty of Science Oujda Morocco Department of Mathematics Faculty of Science URAC04 Oujda Morocco Faculty of Medicine and Pharmacy University Mohamed I Oujda Morocco Health Career Training Institute & Faculty of Sciences Oujda Morocco

A retrospective study was conducted in 2008 on 681 in Eastern Morocco in order to estimate the incidence of cervical and breast cancer, and to determine the social determinants and risk factors associated with these two types of cancer. Another goal of the study was to give health decision makers evidence of the necessity for early diagnosis and treatment. A questionnaire was used before the clinical gynecological examination and sampling cell for the Pap smear. Any woman with a Pap smear suspect had to do a biopsy at the reference centre. Physicians, obstetricians and midwives in the consultation process did gynecological examination and breast palpation. Patients with a suspicious nodule underwent ultrasound and mammography by radiologists on site. Gynecological samples were carried out systematically to all ever-married women to detect cancer of the cervix. Software Excel and SPSS 17 were used for data processing. Patients with high social status were more susceptible to develop breast cancer whereas women with cervical cancer were poor, belonging to a class with a low marital status of widowed or divorced having been married at an early age. The majority of women were married (81%), poor (80%) and illiterate (66%). Breastfeeding women were less affected by breast cancer than women not breastfeeding. For cervical cancer, the difference was not statistically significant. Women using contraceptives were vulnerable to both breast and cervical cancer. For cervical cancer, over 15% of women with a family history were screened positive. No relationship was found between breast cancer and family history. Taking into account regional particularities, we stress the importance of social determinants and risk factors and show that our results are consistent with those published by other researchers. Breast and cervical cancers constitute a real challenge in Morocco. Their socioeconomic burden can be reduced by early detection and treatment. The delayed diagnosis complicates

关键词： Cervical Breast Cancer Determinants Risk Factor Strategy Morocco

Estimation of direct and indirect cost of diabetes in Morocco

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Biomedical Science and Engineering 2013年第7期6卷 732-738页

作者： Wiam Boutayeb Mohamed E. N. Lamlili abdesslam Boutayeb Saber Boutayeb Department of Mathematics Faculty of Sciences University Mohamed 1st Oujda Morocco Department of Medical Oncology National Institute of Oncology Rabat Morocco Laboratory of Stochastic and Determinist Modeling Research Unit Associated to CNRST Faculty of Sciences University Mo- hamed 1st Oujda Morocco

Due to its chronic nature with severe complications, diabetes needs costly prolonged treatment and care. The high economic burden of diabetes is particularly threatening low and middle income countries. World-wide, studies have shown that the cost of diabetes per person is much higher than the per capita health expenditure. This study is the first to estimate the direct and indirect cost of diabetes in Morocco. The direct cost of diabetes was computed by assuming three scenarios of prices (low, medium and high) due to different prices of insulin, oral drugs and other items used in diabetes treatment and care. Indirect costs of diabetes were estimated by the lifetime forgone earnings caused by premature death and disability due to diabetes. The direct cost of diabetes in Morocco was estimated to be between US $0.47 and US $1.5 billion whereas the indirect cost was estimated to be around US $2 billion accounting for 57% of the total cost of diabetes under the high cost scenario, 69% under the medium scenario and 81% under the low cost scenario. The average per capita indirect cost was estimated to be US $1113, relatively higher than the direct cost of diabetes which was seen to vary from US$ 259 to US $830. The results yielded by this study were compared to those obtained by similar studies in different regions and countries of the world. As a conclusion, the findings of this study indicate a high economic burden of diabetes and stress the importance that Moroccan health decision makers should give to sensitisation, early diagnosis and treatment of diabetes especially with the crucial growing trend of diabetes prevalence.

关键词： Diabetes Direct Cost Indirect Cost Prevalence Productive Life Years Disability

The Dynamics of Suspended Particulate Matter in the Oued Nachef(Tafna Basin,Algeria):Typology of Flood Events and Contribution to Sediment Transport

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geological Resource and Engineering 2020年第5期8卷 145-160页

作者： Kazi Tani Hycham abdesslam Bouanani Abderrazak Baba-Hamed Kamila Probst Jean-Luc Laboratory N°25 Dpt.HydraulicInstitute of Science and TechnologyMaghnia University Center13300MaghniaAlgeria Laboratory N°25 Dpt.HydraulicFaculty of TechnologyUniversity Abou Bakr Belkaid13300TlemcenAlgeria Laboratory of Functional Ecology and Environment University of ToulouseCNRSToulouse INPUniversity Toulouse 3-Paul Sabatier(UPS)Toulouse 31062France

This article focuses on the study of sediment transport during flood events in the Oued Nachef watershed that feeds the Mefrouche *** understand the sediment dynamics in this watershed,ANRH data on instantaneous water discharges and the respective concentrations of suspended particulate matter were *** enabled the selection of some of the largest flood events over a 24-year period in order to establish the log-log relationships between sediment load(concentration and flux)and water ***,the discharge-concentration relationships revealed hysteresis phenomena that enabled a flood typology to be established and classified into seven categories,thus showing very different transfer dynamics in relation to flood *** results showed that Category 6 floods presenting hysteresis in the form of a figure of eight exported almost 44%of the suspended particulate matter load while representing just 29%of the flow discharge.

关键词： Algeria Oued Nachef suspended sediment transport flood hysteresis typology

Maternal and infant health in urban and rural areas in Morocco: Analysis of the preliminary results of the National Survey on Population and Family Health (EPSF 2011)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Health 2012年第8期4卷 549-553页

作者： abdesslam Boutayeb Wiam Boutayeb Mohamed E. N. Lamlili Laboratory of Stochastic and Deterministic Modelling Research Unit Associated to CNRST Faculty of Sciences University Mohamed Ier Oujda Morocco

Background: The last Moroccan population and family health survey (EPSF 2011) was carried out between November 2010 and March 2011. The final report and the whole database are not yet accessible while a preliminary report was released early March 2012. The information given so far does not allow for a complete evaluation of the present health situation in Morocco. However, a partial equity analysis can be devoted to the comparison of health indicators in terms of gender and urban-rural gaps. Method: 1) Questionnaires: a household questionnaire dealt with household characteristics, general health, housing condition and anthropometric data for children less than six years of age. A second questionnaire was devoted specifically to ever married women and dealt with their resources, marriage, reproductive health, family planning, AIDS/SIDA, healthcare and nutrition. 2) Data collection: data were collected through the national survey using a three-stage stratified sampling design to select 640 clusters covering the 16 Moroccan regions. A total of 15,577 households were randomly drawn, providing a sample of 75,061 individuals (51.1% females and 48.9% males) for investigation. 3) Analysis: in this short report, we relied only on partial data released by the Ministry of Health in a preliminary report. We used absolute differences and relative ratios to study the evolution of gender and urban-rural gaps on the basis of socioeconomic indicators. Results and Discussion: The Moroccan population seems to be in the last phase of its demographic transition. The total fertility rate decreased from 5.6 children per woman in 1980 to 2.5 in 2011. The mean age of first marriage went from 24 years for men and 17.5 years for women in 1960 to 31.5 years and 26.3 in 2011 for men and women respectively. The age structure is showing a trend of ageing population. Generally, health indicators related to reproductive and women’s health improved noticeably and consequently, maternal and infant mo

关键词： Health Equity Gender Rural Urban Indicators Maternal Infant

Mathematical Modelling and Simulation of <i>β</i>-Cell Mass, Insulin and Glucose Dynamics: Effect of Genetic Predisposition to Diabetes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Biomedical Science and Engineering 2014年第6期7卷 330-342页

作者： Wiam Boutayeb Mohamed E. N. Lamlili abdesslam Boutayeb Mohamed Derouich National School of Applied Sciences University Mohammed First Rabat Morocco URAC04 LaMSD Department of Mathematics and Computer Sciences Faculty of Sciences University Mohammed First Rabat Morocco

Worldwide, diabetes is affecting 370 million people, causing nearly five million deaths and absorbing more than 471 billion USD per year. Mathematical models have been developed to simulate, analyse and understand the dynamics of β-cells, insulin and glucose. In this paper, we consider the effect of genetic predisposition to diabetes on dynamics of β-cells, glucose and insulin. We assume that the β-cell dynamics is governed by the differential equation: . The model indicates different behaviours according to the presence or absence of genetic predisposition. In presence of predisposition (ε = 1), the model shows three equilibrium points: a stable physiological equilibrium point (G = 100, I = 20, β = 600), a stable trivial pathological equilibrium point (G = 600, I = 0, β = 0) and a saddle point (G = 250, I = 9.8, β = 129.36). In absence of predisposition (ε = 0), the model has only two equilibrium points: an unstable pathological equilibrium point (G = 600, I = 0, β = 0) and a stable physiological equilibrium point (G = 82.6, I = 23, β = 900). In order to see how physical activity, obesity and other factors affect insulin sensitivity, simulations are carried out with different values of insulin induced glucose uptake rate (c), β-cell maximum insulin secretory rate (d) and environmental capacity (K).

关键词： Type 2 Diabetes Mathematical Modelling Physiological Equilibrium Pathological Equilibrium

The rise of diabetes prevalence in the Arab region

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Epidemiology 2012年第2期2卷 55-60页

作者： abdesslam Boutayeb Mohamed E. N. Lamlili Wiam Boutayeb Abdellatif Maamri Abderrahim Ziyyat Noureddine Ramdani Department of Biology Faculty of Science University Mohamed Ier Oujda Morocco Health Career Training Institute & Faculty of Sciences Oujda Morocco Laboratory of Stochastic and Determinstic Modelling & Research Unit Associated to CNRST Faculty of Sciences University Mo-hamed Ier Oujda Morocco.

Introduction: Arab populations have many similarities and dissimilarities. They share culture, language and religion but they are also subject to economic, political and social differences. The purpose of this study is to understand the causes of the rising trend of diabetes prevalence in order to suggest efficient actions susceptible to reduce the burden of diabetes in the Arab world. Method: We use principal component analysis to illustrate similarities and differences between Arab countries according to four variables: 1) the prevalence of diabetes, 2) impaired glucose tolerance (IGT), 3) diabetes related deaths and 4) diabetes related expenditure per person. A linear regression is also used to study the correlation between human development index and diabetes prevalence. Results: Arab countries are mainly classified into three groups according to the diabetes comparative prevalence (high, medium and low) but other differences are seen in terms of diabetes-related mortality and diabetes related expenditure per person. We also investigate the correlation between the human development index (HDI) and diabetes comparative prevalence (R = 0.81). Conclusion: The alarming rising trend of diabetes prevalence in the Arab region constitutes a real challenge for heath decision makers. In order to alleviate the burden of diabetes, preventive strategies are needed, based essentially on sensitization for a more healthy diet with regular exercise but health authorities are also asked to provide populations with heath- care and early diagnosis to avoid the high burden caused by complications of diabetes.

关键词： Arab Region Diabetes Prevalence Transition Human Development Regression Principal Component Analysis

Annular pancreas producing duodenal obstruction: A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Gastroenterology 2013年第3期3卷 202-204页

作者： abdesslam Bouassria Hicham Elbouhaddouti Ouadii Mouaqit El Bachir Benjelloun Abdelmalek Ousadden Khalid Mazaz Khalid Ait Taleb Department of General Surgery “A” University Hospital Hassan II Fez Morocco Department of General Surgery “B” University Hospital Hassan II Fez Morocco

Annular pancreas is a rare congenital anomaly characterized by the presence of ectopic pancreatic tissue surrounding the duodenum. This malformation is usually asymptomatic in adults, but can manifests as pancreatitis, duodenal stenosis, or duodenal or gastric ulceration. We report the case of a young patient of 18 years old hospitalized for epigastric pain and vomiting, in whom radiological investigations showed an annular pancreas. At operation, a complete obstruction of the duodenum between its first and second parts was found, caused by an annular pancreas. No other congenital anomaly of the intra abdominal organs was noted. A gastroenterostomy was performed. Both the rarity of this congenital abnormality and its successful correction by surgical means have prompted us to make the following presentation.

关键词： Annular Pancreas Duodenal Stenosis Gastroenterostomy