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外推法导引及应用

数学进展 2024年第1期53卷 13-40页

作者： claude BREZINSKI Michela REDIVO-ZAGLIA 保罗·潘勒韦实验室法国国家科学研究中心混合研究单位8524里尔大学法国里尔59655 帕多瓦大学意大利帕多瓦35122

在数值科学和应用科学中,人们经常需要考虑多种类型的序列:标量、向量、四元数、矩阵以及后来出现的张量.这些序列可能收敛,也可能发散.当它们收敛时,其收敛速度可能会非常缓慢,以至于其实际用途十分有限.在某些情况下,可以修改建立这... 详细信息

在数值科学和应用科学中,人们经常需要考虑多种类型的序列:标量、向量、四元数、矩阵以及后来出现的张量.这些序列可能收敛,也可能发散.当它们收敛时,其收敛速度可能会非常缓慢,以至于其实际用途十分有限.在某些情况下,可以修改建立这些序列的过程,但在其他情况下,这个过程是一个无法进入的黑箱.那么,规避这一困难的一个可行方法就是将序列变换成另一个序列,希望它能收敛到相同的极限,并且收敛得更快.这种序列变换背后的思想就是外推法.本文是关于这些方法中最重要的方法以及其理论基础和算法方面的导引.本文还介绍了一些应用.

关键词：外推法收敛加速序列变换安德森加速张量非线性方程吉布斯现象

Water Quality on the Basement Areas in Kouba-Adougoul and Its Surroundings, Guera Province, Chad

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Journal of Geoscience and Environment Protection 2024年第9期12卷 388-406页

作者： Tekoum Leontine Benadjingar Nguelmbaye Jean claude Doumnang Mbaigane Laboratoire de geologie geomorphologie et de teledetection Dpartement de Gologie Facult de Sciences Exactes et Appliques Universit de NDjamna NDjamena Chad Laboratoire hydro-gosciences et reservoirs Dpartement de Gologie Facult de Sciences Exactes et Appliques Universit de NDjamna NDjamena Chad

Water is an essential element for all forms of life. The quantity and quality of water are a problem in places. In Kouba Adougoul and its surroundings in south guera, water-related health problems are reported. That is why this study focuses on the quality of water in the basement areas, of Kouba Adougoul. Our objective is to contribute to a better understanding of water of human consumption in these areas for this, we carried out a physicochemical and bacteriological control on a number water point. Ten water points were collected during May 2022 for analysis. To achieve this objective, we made the in-situ analysis of physical parameters such as pH, electrical conductivity, and temperature. These measurements were made using the multi-parameter kit. The result shows that, the water temperatures vary from 24.4˚C to 27.4˚C proving that the waters are from deep depths. For the use of these waters, it is necessary to take certain precautions. The pH values varied between 6.15 and 7.78, an average of 6.77 giving some waters an aggressive character. It was low mineralized, with electrical conductivity averages ranging from 182.1 to 2100 μS/cm−1 an average of 586.36 μS/cm−1. For the chemical parameters, it is by hydrometric titration that the content of the ions was determined. The determination of the various coliforms in these waters was carried out by its various methods which led to detecting that the waters of Kouba Adougoul are turbid, and present high proportions of nitrates, iron and ammonium. The presence of pathogenic germs, such as total coliforms and thermo-tolerant coliforms in these waters, has been demonstrated. For their consumption, these waters deserve treatment beforehand. In the study area, the anthropogenic activities are considered the most serious sources of groundwater.

关键词： Environmental Pollution Hydrochemistry Aquifers Crystalline Basement Kouba-Adougoul (Guera-Chad)

Gross Alpha and Beta Activities and Related Lifetime Risks Assessment Due to Ingestion of Drinking Water from Different Sources in the District of Abidjan, Cote d’Ivoire

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World Journal of Nuclear Science and Technology 2024年第1期14卷 86-96页

作者： Ponaho claude Kezo Issa Konate Dabo Salif Ignace Agba Laboratory of Environmental Science and Technology University Jean Lorougnon Guede (UJLoG) Daloa C&#244te d’Ivoire Laboratory of Environmental and Solar Energy Sciences University Felix Houphouet Boigny (UFHB) Abidjan C&#244te d’Ivoire Laboratory of Fundamental and Applied Physics University Nangui Abrogoua (UNA) Abidjan C&#244te d’Ivoire

Drinking good quality water is essential for better health. It is therefore essential to assess the radiological quality of all water consumed in the District of Abidjan in order to prevent related hazards. Thus, the objective of this study was to assess the risk of cancer due to the ingestion of alpha and beta emitting radionuclides in the different types of water consumed in the region. A total of 63 water samples with 43 tap water samples, 5 bottled mineral water and 15 sachet water samples was collected and taken to GAEC laboratory for analysis. The low background Gas-less Automatic Alpha/Beta counting system (Canberra iMaticTM) was used to determine alpha and beta activity concentrations. Activity concentrations of both gross alpha and gross beta obtained in water sample were respectively lower than the WHO recommended limits of 0.1 Bq/l and 1 Bq/l. Also, the annual effective dose and total equivalent effective dose found in mineral bottled water samples were higher than in other types of water. The assessment of radiological lifetime risk has shown values of cancer risk due to ingestion alpha and beta emitters lower than recommended limit. These results indicate that there is no health hazard associated to consumption of water in the District of Abidjan.

关键词： Gross Alpha and Beta Activities Drinking Water Effective Dose Radiological Lifetime Risks

Finite-temperature ductility-brittleness and electronic structures of Al_(n)Sc(n=1,2 and 3)

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Rare Metals 2024年第8期43卷 3974-3989页

作者： Xue-Qian Wang Ying Zhao Hao-Xuan Liu Shu-Chen Sun Hong-Bo Yang Jia-Min Zhong Gan-Feng Tu Song Li Yu-Dong Zhang claude Esling Hai-Le Yan Liang Zuo Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Rare Earth Functional Materials(Xiong'an)Innovation Center Co. Ltd.Xiong'an 071700China Laboratoire d'étude des Microstructures et de Mécanique des Matériaux(LEM3) Unikersitéde Lorraine57045MetzFrance

Finite-temperature ductility-brittleness and electronic structures of Al_(3)Sc,Al_(2)Sc and AlSc are studied comparatively by first-principles calculations and ab initio molecular *** show that Al_(3)Sc and Al_(2)Sc are brittle at both ground state and finite temperatures,while AlSc possesses a significantly superior *** ground state,AlSc is ductile from Pugh's and Poisson's criteria,while it is brittle in Pettifor's *** ductility of all Al_(3)Sc,Al_(2)Sc and AISc improves greatly with the elevated ***,the Cauchy pressure of AlSc undergoes a transition from negative to *** T>600 K,AlSc is unequivocally classified as ductile from all criteria *** all compounds,the Al-Al bond originated from s-p and p-p orbital hybridizations,and the Al-Sc bond dominated by p-d covalent hybridization,are the first and second strongest chemical bonds,*** explain the difference in mechanical properties,the mean bond strength(MBS)is introduced in this *** weaker Al-Al bond in AlSc,leading to a smaller MBS,could be the origin of the softer elastic stiffness and superior intrinsic *** longer length of the Al-Al bond in AlSc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional *** longer length of the Al-Al bond in AISc is responsible for its weaker bond ***,the enhanced metallicity of the Al-Al bond in AlSc would also contribute to its exceptional ductility.

关键词： Al-Sc Target materials Intrinsic ductility Finite-temperature elastic constant First-principles calculation

31 Plant Species against Blood Feeding and Disease Vectors Insects: Beyond Anti-Insect Properties, Unvalued Opportunities and Challenges for Health and Sustainability

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Pharmacology & Pharmacy 2024年第5期15卷 167-206页

作者： Prudence Bararunyeretse Jean claude Niyokwizera Esperance Gateretse Mathias Hitimana Research Center for Natural and Environmental Sciences (CRSNE) University of Burundi Bujumbura Burundi Institutes of Agronomic Sciences of Burundi (ISABU) Bujumbura Burundi East African Nutritional Sciences Institute (EANSI) University of Burundi Bujumbura Burundi

Plants with bioactive properties are greatly useful in preventing and controlling blood-sucking and disease-vector invertebrates, particularly in developing countries and low-income communities. Their application is a promising alternative to synthetic compounds whose use remains a health, environmental, and economic challenge. However, many are still unknown and unvalued, while others are becoming ignored and threatened. The main objective of this ethnobotanical study is to identify and characterize indigenous and locally grown plants against blood-sucking and disease-vector insects. Salient opportunities and challenges of using these plants are documented and discussed. Semi-structured interviews, using a prepared questionnaire, were conducted with 228 informants. The consensus index (CI) was calculated to analyze the reliability of the collected information. The identified 31 anti-insect plant species belong to 20 botanical families, four morphological categories, and six habitat types. They can be categorized as insecticidal plants (42% of the total), insect repellent (42% of the total), and both insecticidal and insect repellent (16% of the total). More than 54% of these are still abundant in the study area, while about 35.5% have become rare and difficultly accessible. Based on the numerical importance of related anti-insect plant species, the seven targeted blood-sucking insects range in the following decreasing order: Jiggers (16 species) > Fire Ants (9 species) > Flies (8 plants) > Mosquitoes (4 species) > Fleas (2 species) > Bedbugs (1 species) > lice (0 species). The three most commonly used plants, with the highest confirmation indices, are Tetradenia riparia (ICs = 0.712), Eucalyptus globulus subsp. maidenii (ICs = 0.302), and Solanum aculeastrum (ICs = 0.288). The antimicrobial role of many locally grown anti-insect plants and the multiple other associated valorization possibilities are ignored by most informants. Domesticating, propagating, protecting

关键词： Blood-Feeding Insects Anti-Insect Plants Biopesticides Sustainability Burundi

New Insights in the Biodegradability and the Ecotoxicological Effects of Solar Products Containing Mineral and Chemical UV-Filters on Marine Zoo- and Phytoplanktons: An in silico and in vitro Study

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Journal of Cosmetics, Dermatological Sciences and Applications 2024年第1期14卷 98-111页

作者： Jean-claude Hubaud Karim Mekideche Jean-Eric Branka Luc Lefeuvre HELIOSCIENCE Cité de la cosmétique 2 rue Odette Jasse Marseille France EPHYSCIENCE 498ter route de Saint Joseph de Porterie Nantes France Laboratoires Dermatologiques d’Uriage Neuilly-sur-Seine France

Background: Cosmetic formulations, and particularly solar products which contain mineral and chemical UV-filters, are often suspected of causing harmful effects on marine fauna and flora. After the publication of our work in 2019 concerning the ecotoxicological effects of such formulations on corals (Seriatopora hystrix), we here provide some new information about the biodegradability and the ecotoxicological effects of these products on marine zoo- and phytoplankton. Therefore, we choose to realize in silico and in vitro studies of the biodegradability of several solar products but also to evaluate the ecotoxicological effects of these products on one phytoplankton, i.e. Phaeodactylum tricornutum, and one zooplankton, i.e. Acartia tonsa, of a great importance for sea species survival (notably as sources of food). Materials and methods: Two different approaches were used to study the biodegradability of the tested products: One in silico method and an in vitro one. 2 solar products were involved in the in silico study which consisted in the determination of the degradation factor (DF) of each ingredient of the tested formulas in order to finally obtain their estimated biodegradability percentage. Already available data concerning each ingredient coupled to a computer model developed with one of our partners were used to achieve this study. The in vitro study involved 8 formulas containing UV-filters and was led by following the OECD 301 F guidelines. Ecotoxicological studies of 7 of the formulas containing UV-filters were for their part realized by following the ISO 10253 guidelines for the experiments led with Phaeodactylum tricornutum, and the ISO 14669 guidelines for the experiments led with Acartia tonsa. In these studies, the effect of each tested product on crustaceans’ mortality and algal growth inhibition was assessed. Results: The in silico study predicted that formulas containing chemical UV-filters display a high biodegradability (superior to the threshol

关键词： UV-Filters Chemical UV-Filter Biodegradability Ecotoxicology in silico in vitro Zooplankton Phytoplankton Phaeodactylum tricornutum Acartia tonsa

Involvement of haptoglobin in disease development

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World Journal of Hematology 2024年第2期11卷 1-7页

作者： Romaric Tuono De Manfouo JosuéSimo Louokdom Bernard claude Chetcha Larissa Michelle BakamMagoua Prosper Cabral Biapa Nya Constant Anatole Pieme claude Tayou Tagny Department of Microbiology ParasitologyHematologyand Infectious DiseasesHematology UnitFaculty of Medicine and Biomedical SciencesUniversity of Yaoundé1Yaoundé296Cameroon Higher Institute of Health Sciences Universitédes MontagnesBangangté296Cameroon Public Health and Biotechnology Research Laboratory(LAPHER-Biotech) Faculty of SciencesUniversity of Yaoundé1Yaoundé296Cameroon Faculty of Sciences Universitéde DschangDschang 296Cameroon Department of Biochemistry Faculty of Medicine and Biomedical SciencesUniversity of Yaoundé1Yaoundé296Cameroon

Haptoglobin(HP)is a liver glycoprotein that is actively synthesized during in-flammatory and hemolytic *** also has pro-oxidant and proinflam-matory properties,which are a function of its *** genetic polymorp-hism of the chains leads to synthesis of three phenotypes/proteins,which are related to the number and type of chains and their molecular weight,namely HP1-1,HP1-2 and *** with HP2-2 have more vascular complications,while those with HP1-1 have *** is involved in the worsening of diseases,such as HP2-2 in aggravation of vaso-occlusive crises in sickle cell disease,and worsening of the pathophysiology of other *** contrast,HP1-1 confers better protection against *** of this suggests that further studies should be conducted,including experimental and analytical studies focused on de-monstrating the influence of different HP genotypes on individual clinical and hematological *** would help in understanding the role played by this genetic polymorphism in the pathophysiology of diseases.

关键词： Haptoglobin Protein Properties Polymorphism Diseases

Predictive Factors for Pre-Eclampsia: A Case-Control Study in Two Hospitals in Yaounde

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Open Journal of Obstetrics and Gynecology 2024年第4期14卷 565-574页

作者： Junie Annick Metogo Ntsama Ines Winnie Gouanfo claude Hector Mbia Wilfried Loic Tatsipie Pascal Mpono Madye Ngo Dingom Felix Essiben claude Cyrille Noa Ndoua Faculty of Medicine and Biomedical Sciences University of Yaound&#233 I Yaound&#233 Cameroon Faculty of Medicine and Pharmaceutical Sciences University of Dschang Dschang Cameroon

Introduction: Pre-eclampsia is a major cause of maternal and prenatal morbidity and mortality, that complicates 2% to 8% of pregnancies worldwide. The aim of this study was to determine the predictive factors for pre-eclampsia in two hospitals in the city of Yaoundé. Methods: A case-control study was conducted at the Gynaecology & Obstetrics department of the Yaoundé Gynaeco-Obstetric and Paediatric Hospital (YGOPH) and the Main Maternity of the Yaoundé Central Hospital (MM-YCH) from February 1 to July 30, 2022. The cases were all pregnant women presenting with pre-eclampsia. The control group included pregnant women without pre-eclampsia. Descriptive statistics followed by logistic regression analyses were conducted with level of significance set at p-value Results: Included in the study were 33 cases and 132 controls, giving a total of 165 participants. The predictive factors for pre-eclampsia after multivariate analysis were: primiparity (aOR = 51.86, 95% CI: 3.01 - 1230.96, p = 0.045), duration of exposure to partner’s sperm Conclusion: The odds of pre-eclampsia increased with primiparity, duration of exposure to partner’s sperm < 3 months, personal history of pre-eclampsia and maternal history of pre-eclampsia. Recognition of these predictor factors would improve the ability to diagnose and monitor women likely to develop pre-eclampsia before the onset of disease for timely interventions.

关键词： Pre-Eclampsia Predictive Factors Yaoundé

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反倾销嵌入全球生产网络的级联效应仿真研究

管理科学学报 2024年第8期27卷 1-22页

作者：乔小勇吴晓雪薛蕊 claude Baron 沈煌南赵乔北京工业大学经济与管理学院北京100124 法国国家科学研究中心系统分析与架构实验室图卢兹31031 复旦大学管理学院上海200437 首都经济贸易大学经济学院北京100071

本研究将复杂网络理论应用于投入产出模型并将其引入宏观经济学生产函数理论模型,对反倾销嵌入全球生产网络的内在机理与其产生的级联效应展开探讨与仿真模拟分析.研究发现:基于网络视角与投入产出关系,反倾销冲击对中间产品的贸易抑制... 详细信息

本研究将复杂网络理论应用于投入产出模型并将其引入宏观经济学生产函数理论模型,对反倾销嵌入全球生产网络的内在机理与其产生的级联效应展开探讨与仿真模拟分析.研究发现:基于网络视角与投入产出关系,反倾销冲击对中间产品的贸易抑制作用要明显大于最终产品,多次跨境的中间品将会累积增加反倾销带来的贸易成本;反倾销带来的行业引致需求量降低与出口贸易受到抑制以及行业与国家总产出水平的波动等影响,会沿着以中间品贸易为基础的全球生产网络中的投入产出关系进行传播,从而产生显著的级联效应,并且该效应会随着不同国家-部门节点之间的联系紧密程度(贸易量)的降低而衰减;反倾销产生的级联效应不仅涉及全球生产网络中直接关联节点即涉案国(调查国与被调查国)的国内上下游行业,而且波及间接关联节点即非涉案国的第三方国家和地区,进而影响全球多边贸易发展,同时,级联效应也阻碍了网络节点参与全球价值链生产分工,导致了节点隶属国(地区)的国内价值链被拉长;反倾销嵌入全球生产网络后,会通过整个生产网络产生总量波动效应,从而改变全球生产网络的拓扑结构,即全球生产网络变的相对稀疏、节点间网络距离拉长等.

关键词：反倾销贸易摩擦政策冲击全球生产网络级联效应