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Evaluation of Four Anthropogenic Activity Impacts on Heavy Metal Quality of the Kumba River in the South West Region of Cameroon

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Journal of Water Resource and Protection 2024年第5期16卷 361-380页

作者： Martin Keghe Nkobe Barthelemy Ndongo Kanouo boris Merlain Djousse Salomon Nyasse Institute of Agricultural Research for Development (IRAD) Yaound&#233 Cameroon Faculty of Agronomy and Agricultural Sciences (FASA) University of Dschang Dschang Cameroon

Anthropogenic activities have contributed to pollution of water bodies through deposition of diverse pollutants amongst which are heavy metals. These pollutants, which at times are above the maximum concentration levels recommended, are detrimental to the quality of the water, soil and crops (plant) with subsequent human health risks. The objective of the work was to evaluate the impacts of human-based activities on the heavy metal properties of surface water with focus on the Kumba River basin. Field observations, interviews, field measurements and laboratory analyses of different water samples enabled us to collect the different data. The results show four main human-based activities within the river basin (agriculture, livestock production, domestic waste disposal and carwash activities) that pollute surface water. Approximately 20.61 tons of nitrogen and phosphorus from agricultural activities, 156.48 tons of animal wastes, 2517.5 tons of domestic wastes and 1.52 tons of detergent from carwash activities were deposited into the river each year. A highly significant difference at 1% was observed between the upstream and downstream heavy metal loads in four of the five heavy metals tested except for copper that was not significant. Lead concentrations were highest in all the activities with an average of 2.4 mg∙L−1 representing 57.81%, followed by zinc with 1.596 mg∙L−1 (38.45%) and manganese with 0.155 mg∙L−1 (3.74%) for the different anthropogenic activities thus indicating that these activities highly lead to pollution of the Kumba River water. The level of zinc and manganese was significantly influenced at ρ 005 by anthropogenic activities though generally the variations were in the order: carwash (3.196 mg∙L−1) −1) −1) −1) r

关键词： Metal Properties Human-Based Activities Kumba River Basin Surface Water

On the “Onion Husk” Algorithm for Approximate Solution of the Traveling Salesman Problem

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1557-1570页

作者： Mikhail E. Abramyan Nikolai I. Krainiukov boris F. Melnikov Faculty of Computational Mathematics and Cybernetics Shenzhen MSU-BIT University Shenzhen China Department of Algebra and Discrete Mathematics Southern Federal University Rostov-on-Don Russian Federation

The paper describes some implementation aspects of an algorithm for approximate solution of the traveling salesman problem based on the construction of convex closed contours on the initial set of points (“cities”) and their subsequent combination into a closed path (the so-called contour algorithm or “onion husk” algorithm). A number of heuristics related to the different stages of the algorithm are considered, and various variants of the algorithm based on these heuristics are analyzed. Sets of randomly generated points of different sizes (from 4 to 90 and from 500 to 10,000) were used to test the algorithms. The numerical results obtained are compared with the results of two well-known combinatorial optimization algorithms, namely the algorithm based on the branch and bound method and the simulated annealing algorithm. .

关键词： Branch and Bound Method Contour Algorithm “Onion Husk” Algorithm Simulated Annealing Method Traveling Salesman Problem

On Some Properties of Graph of Prefix Code

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1571-1581页

作者： Nikolai I. Krainiukov Mikhail E. Abramyan boris F. Melnikov Faculty of Computational Mathematics and Cybernetics Shenzhen MSU-BIT University Shenzhen China Department of Algebra and Discrete Mathematics Southern Federal University Rostov-on-Don Russian Federation

We investigate decomposition of codes and finite languages. A prime decomposition is a decomposition of a code or languages into a concatenation of nontrivial prime codes or languages. A code is prime if it cannot be decomposed into at least two nontrivial codes as the same for the languages. In the paper, a linear time algorithm is designed, which finds the prime decomposition. If codes or finite languages are presented as given by its minimal deterministic automaton, then from the point of view of abstract algebra and graph theory, this automaton has special properties. The study was conducted using system for computational Discrete Algebra GAP. .

关键词： Finite Languages Minimal Deterministic Automata Concatenation Codes Graph of Automaton Free Algebra

Artificial light at night(ALAN) pollution alters bat lunar chronobiology:insights from broad-scale long-term acoustic monitoring

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Ecological Processes 2024年第1期13卷 176-187页

作者： Han Li Pauline Allen Saige boris Samantha Lagrama Jade Lyons Christina Mills Pauline Moussi Casey Nichols Carter Tacosik Mc Kenzie Tsaousis Nyzaya Livingston Wilson John F.Grider Kevin A.Parker Matina C.Kalcounis-Rueppell Department of Biology University of Nebraska Omaha Department of Biology University of North Carolina Greensboro Colorado Parks and Wild-life Parker Ecology LLC Department of Biological Sciences University of Alberta

Background The timing of behavior and habitat use of nocturnal animals can be influenced by the lunar cycle in nature. The prevalence of artificial light at night(ALAN) has been recognized as a source of environmental pol-lution. The interaction between ALAN and the lunar cycle on bat behavior is important for understanding anthro-pogenic effects on bats. We utilized a decade(2012–2022) of acoustic monitoring data collected in North Carolina, United States, to investigate the relationship between bat activity, lunar cycle, and light pollution. We examined whether the amount of lunar illumination affected species-specific nightly activity and whether hourly bat activity patterns varied between nights with different moon phases. We further investigated if the relationship between bat activity and the lunar cycle might be altered by light *** We found that seven bat species showed activity variation across nights in relation to the amount of moon illumination when ALAN was absent. In general, bats were less active on full moon nights compared to new moon nights. Light pollution interacted with the bat–lunar relationship in five of the seven species, masking the effect of the lunar cycle. We identified delayed bat activity patterns on nights with a full or waxing moon in seven species, and light pollution altered that pattern in four species. Overall, ALAN was associated with decreased bat activity inde-pendent of lunar cycle *** Our study demonstrated that at a broad spatial scale, ALAN negatively affected many North American temperate bat species and altered their lunar chronobiology. As light pollution is spreading to historically dark areas and habitats, ALAN might couple with other threats, such as the white-nose syndrome or climate change, to cause cascading damage in the environment that depends on ecosystem services such as pest control provided by bats. We argue that further research and conservation actions are needed to mitigate

关键词： Artificial light at night ALAN Bats Chiroptera Chronobiology Light pollution Lunar cycle Moonlight

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茶香四溢无双·茶事

室内设计与装修 2024年第9期 90-94页

作者：无 boris(摄影) IN.X屋里门外设计不详

略加粗算,我们和茶的渊源已逾千年。无论从时间还是地理的维度,多元是中国茶事迁延流变中的显要特征,而这也使中国茶的饮法有了更多值得探询演绎的空间。正是在茶文化宽容辽阔的属性下,无双茶事作为泛餐饮空间代表得以构建--远可回溯人... 详细信息

略加粗算,我们和茶的渊源已逾千年。无论从时间还是地理的维度,多元是中国茶事迁延流变中的显要特征,而这也使中国茶的饮法有了更多值得探询演绎的空间。正是在茶文化宽容辽阔的属性下,无双茶事作为泛餐饮空间代表得以构建--远可回溯人文雅趣,照天地心;近能承载雀跃先锋的时代生活,恣意鲜活。

关键词：茶文化餐饮空间茶事茶香

Olefin Polymerization Behavior of Titanium(IV) Complexes with Fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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Chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： Vladislav A.Tuskaev Kasim F.Magomedov Svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia V.Nelyubina Evgenii K.Golubev Maria D.Evseeva Viktor G.Vasil'ev Galina G.Nikiforova Mikhail I.Buzin Vyacheslav S.Bogdanov boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(MMAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHMWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(IV) (Co)polymerization Al/Mg co-catalyst Ultra-high molecular weight polyethylene

Floristic Diversity and Conservation Status of Guineo-Congolese Species in Southeastern Cameroon: The Case of the Gari-Gombo Communal Forest

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Open Journal of Forestry 2024年第1期14卷 87-97页

作者： boris Nyeck Valery Noiha Noumi Nicole Maffo Maffo Victor Awe Djongmo Cedric Djomo Chimi Louis Zapfack Department of Biological Sciences Faculty of Sciences University of Ngaoundéré Ngaoundéré Cameroon Agricultural Research Institute for Development (IRAD) Minko Agricultural Research Station Meyomessala Cameroon Department of live Sciences Higher Teacher Training College University of Bertoua Bertoua Cameroon Department of Plant Biology and Physiology Faculty of Sciences University of Yaoundé I Yaoundé Cameroon Agricultural Research Institute for Development (IRAD) Research Station of Yokadouma Yokadouma Cameroon

The conservation of plant biodiversity has become one of the most important objectives in the sustainable management of Guinean-Congolese ecosystems. However, in the south-east zone of Cameroon, there is a lack of rigor in the management of these forests, which can result in the loss of species of high conservation value. The study was carried out in communal forests in the south-east zone of Cameroon. Its aim was to carry out a floristic inventory and then compare the list of species with the IUCN catalog. Twenty-four plots, each with a surface area of 0.2 ha, were set up in the Gari-Gombo communal forest. All timbers with a DBH ≥ 5 cm were systematically counted. A total of 176 species, belonging to 144 genera and 45 families, were surveyed. Fabaceae (42.08%), Malvaceae (39%), Euphorbiaceae (24.64%), Moraceae (20.92%), Apocynaceae (18.64%), Cecropiaceae (16.60%), Ulmaceae (14.76%), Meliaceae (14.61%), Violaceae (14.08%), Combretaceae (12.67%), Theobroma cacao (21.17%), Baphia leptobotrys (18.06%), Rinorea sp. (14.09%), Musanga cecropioides (12.18%), Terminalia superba (10.32%), Neosloetiopsis kamerunensis (10.14%), Celtis zenkeri (8.29%) and Alstonia boonei (7.77%) were the most important taxa. Nearly 90% of the species in this forest are Guinean species, with a dominance of Guinean-Congolese species (66%). Fourteen (14) threatened species have been identified in the FCGG. This study, which highlights the rich biodiversity of communal forests, is important for guiding biodiversity conservation policies in ecosystems used for production.

关键词： Communal Forest Conservation Status Cameroon Floristic Diversity

Diabetes and Hypertension Are Associated with Food Insecurity in a Cameroonian Population: A Case-Control Study

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Journal of Biosciences and Medicines 2024年第2期12卷 1-21页

作者： boris Ronald Tonou Tchuente Pauline Vervaine Hagbe Hippolyte Tene Mouafo Janvier Aime Fotso Youovop Ousmane Mfopou Mbiondi Javeres Leonel Ntepe Mbah Roussel Guy Nguemto Takuissu Raissa Francoise Ntentie boris Gabin Kingue Azantsa Judith Laure Ngondi Julius Oben Enyong Department of Biochemistry Faculty of Sciences University of Yaounde 1 Yaounde Cameroon Centre for Food Food Security and Nutrition Research Institute of Medical Research and Medicinal Plant Studies Yaounde Cameroon Department of Biosciences COMSATS University Islamabad Islamabad Pakistan Laboratory of Human Metabolism and Non-Communicable Disease Institute of Medical Research and Medicinal Plant Studies Yaounde Cameroon Higher Teacher’s and Training College University of Yaounde 1 Yaounde Cameroon Center of Nutrition and Functional Foods Yaounde Cameroon

Diabetes and hypertension are the most prevalent cardiovascular risk factors. Recent studies showed an increase in the prevalence of food insecurity in our country. The aim of this study was to assess how food insecurity affects the dietary habits, socio-demographic characteristics and metabolic profile of individuals with diabetes or hypertension. This case-control study was conducted among diabetic and hypertensive participants (cases) and diabetic and hypertensive normal (controls) during the screening campaigns for nutrition-related chronic diseases. The sociodemographic, clinical and biochemical parameters of the participants were analyzed. Logistic regression analyses were performed to identify factors associated with diabetes and hypertension in the study population. Bivariate analyses showed that male gender (OR = 1.972;95% CI: 1.250 - 3.089), regular alcohol consumption (OR = 2.012;95% CI: 1.294 - 3.130), low fruit consumption (OR = 1.590;95% CI: 1.016 - 2.488), low dietary diversity (OR = 2.915;95% CI: 1.658 - 5.127) and abdominal obesity (OR = 1.893, CI 95% 1.203 - 2.978) were significantly associated with hypertension. In addition, low fruit consumption (OR = 1.829;95% CI 1.092 - 3.064), low legume consumption (OR = 3.515;95% CI 1.861 - 6.635), and hypertriglyceridaemia (OR = 2.241, 95% CI 1.139 - 4.408) were significantly associated with diabetes. The indirect association observed between food insecurity and diabetes and hypertension suggests the need for nutritional policies aimed at popularizing the production and consumption of fruits and legumes. Similarly, health services need to be aware and informed of the important role that food insecurity can play in the development of diabetes and hypertension.

关键词： Food Insecurity Diabetes Hypertension Cameroon

Using Optical Tweezers to Study the Friction of the Red Blood Cells

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Advances in Bioscience and Biotechnology 2024年第2期15卷 100-111页

作者： Edoukoua Jean Michel Konin Pavel Yale Abadê Ange-boris N’guessan Kouassi Benoit Kouakou Abaka Michel Kouacou Eugene Megnassan Département des Sciences et Techniques Université Alassane Ouattara Bouaké C&#244te d’Ivoire Laboratoire d’Instrumentation Image et Spectroscopie (L2IS) Institut National Polytechnique Félix Houphou&#235t-Boigny (INPHB) Yamoussoukro C&#244te d’Ivoire Classes préparatoires aux grandes Ecoles Université de San Pedro San Pedro C&#244te d’Ivoire Laboratoire de Physique Fondamentale et Appliquée Université Nangui Abrogoua (UNA) Abidjan C&#244te d’Ivoire

In the last two decades the study of red blood cell elasticity using optical tweezers has known a rise appearing in the scientific research with regard to the various works carried out. Despite the various work done, no study has been done so far to study the influence of friction on the red blood cell indentation response using optical tweezers. In this study, we have developed a new approach to determine the coefficient of friction as well as the frictional forces of the red blood cell. This approach therefore allowed us to simultaneously carry out the indentation and traction test, which allowed us to extract the interfacial properties of the microbead red blood cell couple, among other things, the friction coefficient. This property would be extremely important to investigate the survival and mechanical features of cells, which will be of great physiological and pathological significance. But taking into account the hypothesis of friction as defined by the isotropic Coulomb law. The experiment performed for this purpose is the Brinell Hardness Test (DB).

关键词： Friction Indentation Optical Tweezers Tribology Red Blood Cells