检索结果-南通市图书馆

Numerical Study of the Vibrations of Beams with Variable Stiffness under Impulsive or Harmonic Loading

World Journal of engineering and Technology 2024年第2期12卷 401-425页

作者： Moussa Sali Fabien Kenmogne Jean bertin Nkibeu Abdou Njifenjou Laboratory of Materials Mechanics and Civil Engineering National Higher Polytechnic School of Maroua University of Maroua Maroua Cameroon Department of Civil engineering Advanced Teachers Training College of the Technical Education University of Douala Douala Cameroon Laboratory engineering Civil and Mechanics National Advanced School of Engineering University of Yaound&#233 1 Yaound&#233 Cameroon Laboratory of energy Materials Modeling and Method (E3M) National Advanced School of Engineering University of Douala Douala Cameroon Laboratory of Mathematical engineering and Information Systems National Advanced School of Engineering University of Yaound&#233 1 Yaound&#233 Cameroon

The behavior of beams with variable stiffness subjected to the action of variable loadings (impulse or harmonic) is analyzed in this paper using the successive approximation method. This successive approximation method is a technique for numerical integration of partial differential equations involving both the space and time, with well-known initial conditions on time and boundary conditions on the space. This technique, although having been applied to beams with constant stiffness, is new for the case of beams with variable stiffness, and it aims to use a quadratic parabola (in time) to approximate the solutions of the differential equations of dynamics. The spatial part is studied using the successive approximation method of the partial differential equations obtained, in order to transform them into a system of time-dependent ordinary differential equations. Thus, the integration algorithm using this technique is established and applied to examples of beams with variable stiffness, under variable loading, and with the different cases of supports chosen in the literature. We have thus calculated the cases of beams with constant or variable rigidity with articulated or embedded supports, subjected to the action of an instantaneous impulse and harmonic loads distributed over its entire length. In order to justify the robustness of the successive approximation method considered in this work, an example of an articulated beam with constant stiffness subjected to a distributed harmonic load was calculated analytically, and the results obtained compared to those found numerically for various steps (spatial h and temporal τ ¯ ) of calculus, and the difference between the values obtained by the two methods was small. For example for ( h=1/8 , τ ¯ =1/ 64 ), the difference between these values is 17%.

关键词： Successive Approximations Method Direct Integration Differential equations Beams of Variable Stiffness Quadratic Parabola Impulse and Harmonic Loads

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Phytochemical Screening, Study of Acute Toxicity and Hypoglycemic and Antihyperglycemic Activities of Silver Nanoparticles from Guibourtia tessmannii (Harms) J. Leonard (Caesalpiniaceae)

引用

Open Journal of Applied Sciences 2024年第1期14卷 118-130页

作者： Ngoulé Charles Christian eya’ane Meva François so.e eno.e bertin Ngo Nyobe Biwole Caroline Tankeu Séverin elisée songue Pascal Nguene Jean Pierre etame-Loe Gisèle Department of Pharmaceutical Sciences Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Department of Biology of Plant Organisms Faculty of Sciences University of Douala Douala Cameroon

According to the World Health Organization, diabetes affects approximately 347 million people worldwide. Its management is not within the reach of all social classes, therefore medicinal plants are still the first resort for many populations in Africa. The biological material used in this study was the trunk bark of Guibourtia tessmannii. 50 g of trunk bark powder were decocted in 500 ml of distilled water for 5 minutes were carried out. The method used for the synthesis of silver nanoparticles (AgNps) was an organometallic bio-reduction of silver nitrate salts mediated by various secondary metabolites contained in the plant extract. The study of the toxicity acute was conducted according to guideline 423 of the OeCD protocol. The pharmacological activities were each carried out with 28 female rats divided into 7 groups of four rats. It was a question for the hypoglycemic activity of administering various doses of silver nanoparticles and other substances to the rats thirty minutes after the carbohydrate intake and for the anti-hyperglycemic activity of administering the same substances to the rats thirty minutes before the carbohydrate intake. The extraction yield was 8.76%. Only the alkaloid test was negative. After acute toxicity study, the LD50 was greater than 2000 mg/kg. Blood sugar tests revealed that glibenclamide 5 mg/kg, which is the reference molecule, lowered blood sugar more than the other treatments applied in the other batches. It was followed by treatment with silver nanoparticles at a dose of 400 μg/kg in both tests. It was therefore concluded that silver nanoparticles from G. tessmannii are good for the formulation of improved traditional medicines and bring up their afficacity .

关键词： Guibourtia tessmannii Nanoparticles Hypoglycemia Anti-Hyperglycemia

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Management of Vulnating esophageal Foreign Bodies in Burkina Faso

引用

International Journal of Otolaryngology and Head & Neck Surgery 2024年第2期13卷 135-148页

作者： Ibrahima Diallo Aboubacar Gouéta Alseny Camara Assoumi Anatou Biga Mama Brigitte Ouoba edi emmanuel Martial Nao Moustapha Sérémé bertin Priva Ouédraogo Yvette Marie Chantal Gyébré Abdoulaye Keita Alpha Oumar Diallo eNT and HNS Department Yalgado Ouédraogo University Hospital Ouagadougou Burkina Faso eNT and HNS Department Bogodogo University Hospital Ouagadougou Burkina Faso eNT and HNS Department Tengandogo University Hospital Ouagadougou Burkina Faso eNT and HNS Department Conakry University Hospital Conakry Guinea

Introduction: esophageal foreign bodies (eFB) are a diagnostic and therapeutic emergency because of the serious complications they can cause. Aim: This paper aimed to study the vulnating esophageal foreign bodies in the eNT and Head and Neck Surgery departments of the Yalgado Ouedraogo and Bogodogo University Hospital. Methodology: This was an analytic cross-sectional study with retrospective data collection over 10 years (2012-2021). Results: We collected 91 cases of vulnating esophageal foreign bodies, i.e. 9.1 cases/year (4.7%). The mean age of the patients was 14 ± 19 years. The sex ratio was 1.6. The circumstances of occurrence were dominated by accidental ingestion of vulnating esophageal foreign bodies (98.9%). The average time to consultation was 7.5 hours. Dysphagia was the dominant symptom (64.8%). Cervico-thoracic radiography found dual contour radiopaque images in 71.4%. esophagoscopy with rigid tube was performed in 97.8%. The average time for extraction of the vulnating esophageal foreign bodies was 8 hours. Vulnerating esophageal foreign bodies were non-organic in 84.6%. The button cell represented 64.8%. Their location was cervical in 61.5% intraoperatively. The lesion assessment found ulcerative lesions in 42.9% (p Conclusion: Vulnating esophageal foreign bodies are relatively frequent in our eNT practice. Although their diagnosis is often easy, their treatment is still difficult and requires multidisciplinary management. Thus, for us, prevention remains the first effective weapon.

关键词： Foreign Bodies esophagus Vulnerable Management Sequelae

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Maternal Fetal Prognosis: Pregnancy and Delivery in Women of 40 Years Old and Over in a Second Reference Hospital in Bamako

引用

Open Journal of Obstetrics and Gynecology 2024年第4期14卷 509-519页

作者： Samaké Alou Diarra Lasseny Keita Mamadou Haidara Dramane Haidara Mamadou Diallo Mamadou Konaté Moussa Maiga Mariam Mohamed Saydi Ag Med elmehdi elansari Kassogue Djibril Seydou Zana Dao Samake Hawa Konate Karim Dembele bertin Coulibaly Moussa Mariko Seydou Collarete Dohino Reference Health Center of Commune VI of the Bamako District Bamako Mali Bamako Dermatology Hospital (BDH) Bamako Mali Kalaban Coro Reference Health Center Bamako Mali Timbuktu Hospital Timbuktu Mali Reference Health Center of Commune II of the Bamako District Bamako Mali Reference Health Center in Commune V of the Bamako District Bamako Mali National Institute for Training in Health Sciences Bamako Mali Mali Hospital Bamako Mali

Introduction: Late pregnancies are considered a public health problem linked to maternal mortality due to their complications. These risks, which worsen with maternal age, should be better known and taken into account in monitoring these pregnancies. Objective: To evaluate the impact of age on the prevalence of obstetric and neonatal complications among parturients of 40 years old and over. Methodology: This was an 11-year retrospective analytical case control study from January 1, 2007 to December 31, 2017. The study population was female patients of 40 years old or older for cases and female patients younger than 40 years of control case. Results: In total, we collected 640 cases of parturients of 40 years old and over out of a total of 84,234 deliveries during the study period;i.e. a frequency of 0.76%. Spontaneous abortion increased in patients of 40 and over with 8.28%. Hypertension and diabetes were higher of women of 40 and over, 52.65%. Concerning the method of admission: 55% of parturients of 40 and over were referrals. Incidents occurring among women of 40 and over were more pronounced than in control cases. Complications during vaginal delivery, cervical tear, perineal tear, uterine dehiscence and uterine rupture are high in our cases, i.e. 11.88%;3.59%;2.19%;2.66. During our study, depending on the type of delivery, the cesarean rate was much higher among women of 40 and over than among control cases, i.e. 54.22% versus 12.24%. Hemorrhages in the 3rd trimester were the main indications for cesarean section. Hemorrhages in the 3rd trimester were more frequent with women of 40 and over, i.e. 10.47%;5.94% versus 1.74% and 0.42%. As for the different types of malformations in parturients, women under 40 years old fetal malformations were absent in 92.29%, on the other hand they were more frequent in patients with 40 years and over, i.e. a normal frequency of 36.72%. Conclusion: Pregnancy at a late age exposes the elderly patient and the newborn to several ri

关键词： Advanced Maternal Age Childbirth Risk Mali

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Maternal and Perinatal Prognosis of Arterial Hypertension and Pregnancy in a Peripheral Health Center in Mali

引用

Open Journal of Obstetrics and Gynecology 2024年第5期14卷 855-867页

作者： Samaké Alou Diarra Lasseny Keita Mamadou Haidara Dramane Haidara Mamadou Diallo Mamadou Konaté Moussa Maiga Mariam MS Ag Med elméhdi elansari Kassogue Djibril Dao Seydou Zana Samake Hawa Konate Karim Dembele bertin Coulibaly Moussa Mariko Seydou Colette Dohinnon Reference Health Center in Commune VI of the Bamako District Bamako Mali Bamako Dermatology Hospital (HDB) Bamako Mali Kalaban Coro Reference Health Center Bamako Mali Timbuktu Hospital Timbuktu Mali Reference Health Center of Commune II of the Bamako district Bamako Mali Reference Health Center in Commune V of the Bamako district Bamako Mali National Institute for Training in Health Sciences Bamako Mali Mali Hospital Bamako Mali

Introduction: Maternal mortality constitutes a public health problem and its rate is an indicator of a country’s development. Among the causes of maternal and perinatal death, high blood pressure associated with pregnancy occupies a significant part. It represents 5% of direct maternal deaths. Objective: to study the maternal and perinatal prognosis of high blood pressure during pregnancy in the Tenenkou reference health center in Mali. Methodology: This was a descriptive, analytical and retrospective cross-sectional study over a period of twelve months from January 1, 2021 to December 31, 2021 and involving 144 cases of high blood pressure associated with pregnancy. Results: We obtained a frequency of 11.75%. The majority of patients 70.9% were aged between 20 - 35 years. The important risk factor found was young age. During our study, 46.5% of patients had performed at least one CPN and only 13.9% performed 04 CPN. Pre-eclampsia was the most common type of high blood pressure during pregnancy, i.e. 61.1%. eclampsia and retroplacental hematoma were the most common maternal complications, respectively 27.8% and 11.1%. The most common fetal complications were premature births and fetal distress with 20.9% and 17.4% respectively. Conclusion: Hypertension associated with pregnancy still remains a major cause of maternal-fetal morbidity and mortality in our context where diagnosis is often late. The main clinical form was preeclampsia. eclampsia and retroplacental hematoma were the most frequent maternal complications. Fetal complications were mainly prematurity and fetal distress.

关键词： Pregnancy High Blood Pressure Prognosis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

epidemiological-Clinical Aspects of Uterine Leiomyoma at the Reference Health Center of Commune VI of the Bamako District

引用

Open Journal of Obstetrics and Gynecology 2024年第5期14卷 674-681页

作者： Alou Samaké Lasseny Diarra Mamadou Keita Dramane Haidara Mamadou Haidara Coulibaly soumana Mamadou Diallo Moussa Konaté Mariam Maiga MS Ag Med elméhdi elansari Kassogue Djibril Dao Seydou Zana Samake Hawa Konate Karim Dembele bertin Coulibaly Moussa Mariko Seydou Colette Dohino Reference Health Center of Commune VI of the Bamako District Bamako Mali Bamako Dermatology Hospital (HDB) Bamako Mali Kalaban Coro Reference Health Center Bamako Mali Hangadoumbo Moulaye Touré Hospital in Gao Gao Mali Timbuktu Hospital Tomboctou Mali Reference Health Center of Commune II of the Bamako District Bamako Mali Reference Health Center in Commune V of the Bamako District Bamako Mali National Institute for Training in Health Sciences Bamako Mali Mali Hospital Bamako Mali

Introduction: Uterine fibroid is a mixed mesenchymal tumor, developing from smooth muscle cells of the myometrium, separated by connective tissue. The majority of fibroids are asymptomatic and do not require any intervention or other exploratory measures. However, in so.e cases fibroids are symptomatic, their treatment should aim to improve symptoms and quality of life. Objectives: Describe the epidemiological-clinical aspects of uterine fibroids in the gynecology and obstetrics department of the reference health center of commune VI of the Bamako district. Methodology: This was a retrospective descriptive study carried out over a period of one year. It concerns all patients seen in consultation in the gynecology and obstetrics department of the reference health center of commune VI. Results: during the study period, the uterine fibroid frequency was 1.80%. During this same period, fibroids represented 5.59% of gyneco-obstetric pathologies operated on in the department. The 30 - 45 year old age group was the most represented with a frequency of 75.63%. The average age was 36.87 years ± 6.2 years with extremes of 25 and 63 years. Married women were the most represented 97.48%. The vast majority of our patients 95.8% were not postmenopausal. The multigravidas were the most represented, i.e. 37.50% with a large part of the pauciparous 41.29%. In our patients, 96.64% had a clinical symptom on their fibroid with the main reason for consultation being the sensation of a pelvic mass in 97.48%. We recorded three cases of infertility as associated factors. Ultrasound was performed in all patients. The location of the myxomatous nuclei was subserosal in the majority in 42.86% and with multiple nodules in 84.85% of cases. The main indication for myomectomy was the failure of medical treatment in 86.49% of cases. Surgical treatment was mainly a myomectomy 93.30%, a hysterectomy was indicated in 6.70%. No cases of death were recorded. Conclusion: Uterine fibroid is a gynecologic

关键词： Myomas Surgery Myomectomy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Phytochemical Screening, Study of Acute Toxicity and Hypoglycemic and Antihyperglycemic Activities of Silver Nanoparticles from Guibourtia tessmannii (Harms) J. Leonard(Caesalpiniaceae)

引用

Open Journal of Applied Sciences（应用科学） 2024年第1期

作者： Ngoulé Charles Christian eya’ane Meva François so.e eno.e bertin Ngo Nyobe Biwole Caroline Tankeu Séverin elisée songue Pascal Nguene Jean Pierre etame-Loe Gisèle

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

X射线光谱分析的原理和应用

X射线光谱分析的原理和应用

引用

作者： e.P.·伯廷(e.P. bertin)

来源：南通市图书馆图书评论

学校读者我要写书评

暂无评论

elevated plasma interleukin-8 as a risk factor for mortality in children presenting with cerebral malaria

引用

Infectious Diseases of Poverty 2023年第1期12卷 47-61页

作者： Jade Royo bertin Vianou Manfred Accrombessi elisée Kinkpé Linda Ayédadjou Ida Dossou-Dagba YéléLadipo Maroufou Jules Alao Gwladys I.bertin Michel Cot Farid Boumédiène Sandrine Houzé Jean François Faucher Agnès Aubouy 无 UMR152 PHARMADeV IRDUPSToulouse University35 Chemin Des Maraichers31400 ToulouseFrance Clinical Research Institute of Benin(IRCB) Abomey CalaviBenin Faculty of Infectious and Tropical Diseases Disease Control DepartmentLondon School of Hygiene and Tropical MedicineLondonUK Paediatric Department Calavi HospitalCalaviBenin Paediatric Department Mother and Child University and Hospital Center(CHU-MEL)CotonouBenin UMR261 MeRIT IRDParis UniversityParisFrance UMR 1094 epiMaCT InsermLimoges University HospitalLimoges UniversityLimogesFrance French Malaria Reference Center APHPBichat HospitalParisFrance Parasitology Laboratory APHPBichat-Claude-Bernard HospitalParisFrance Infectious Diseases and Tropical Medicine Department Limoges University HospitalLimogesFrance NeuroCM Group

Background Cerebral malaria(CM)is a neuropathology which remains one of the deadliest forms of malaria among African *** kinetics of the pathophysiological mechanisms leading to neuroinflammation and the death or survival of patients during CM are still poorly *** increasing production of cytokines,chemokines and other actors of the inflammatory and oxidative response by various local actors in response to neuroinflammation plays a major role during CM,participating in both the amplification of the neuroinflammation pheno.enon and its *** this study,we aimed to identify risk factors for CM death among specific variables of inflammatory and oxidative responses to improve our understanding of CM *** Children presenting with CM(n=70)due to *** infection were included in southern Benin and divided according to the clinical outcome into 50 children who survived and 20 who *** examination was complemented by fundoscopic examination and extensive blood biochemical analysis associated with molecular diagnosis by multiplex PCR targeting 14 pathogens in the patients'cerebrospinal fluid to rule out *** technology and enzyme immunoassay kits were used to measure 17 plasma and 7 urinary biomarker levels,*** were analysed by univariate analysis using the nonparametric Mann-Whitney U test and Pearson’s Chi2 *** and multivariate analyses were conducted separately for plasma and urinary biomarkers to identify CM mortality risk *** Univariate analysis revealed higher plasma levels of tumour necrosis factor(TNF),interleukin-1beta(IL-1β),IL-10,IL-8,C-X-C motif chemokine ligand 9(CXCL9),granzyme B,and angiopoietin-2 and lower urinary levels of prostanglandine e2 metabolite(PGeM)in children who died compared to those who survived CM(Mann-Whitney U-test,P-values between 0.03 ande multivariate logistic analysis highlighted elevated plasma levels of IL-8 as the m

关键词： Cerebral malaria Children Benin Cytokine Plasma Urine Immunologic marker NeuroCM

来源：

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

X射线光谱分析的原理和应用

X射线光谱分析的原理和应用

引用

1983年

作者：（美）伯廷（e.P.bertin）李瑞城等译

本素着重介绍了X射线光谱分析原理和应用。

ISBN: (纸本)54·64656

本素着重介绍了X射线光谱分析原理和应用。

关键词：放射线发光光谱分析

来源：汇雅图书（南通市图书馆... 评论

在线全文

汇雅图书（南通市图书馆）

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：