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Distribution of 26 Metals in the Waters of the Aquatic Ecosystems of the Cotonou Channel and Lake Nokoué, Benin
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作者 Alassane Youssao Abdou Karim Acakpo Nonvignon Magloire Gbaguidi +7 位作者 Kpessou Martin Vitus Mickael Saizonou Léonce Firmin Dovonon Gabin Laly Abdoul Kader Alassane Moussa Emmanuel Azokpota Fabienne Seby Olivier Donard Houénoukpo Henri Soclo 《Journal of Materials Science and Chemical Engineering》 CAS 2023年第2期13-28,共16页
Metallic elements have various origins: natural and anthropogenic sources as geochemical, marine and atmospheric sources resulting from the fallout of pollutants emitted or dust raised and which are transported by wat... Metallic elements have various origins: natural and anthropogenic sources as geochemical, marine and atmospheric sources resulting from the fallout of pollutants emitted or dust raised and which are transported by water and air currents. Thus marine, brackish and fresh continental waters may have high metal concentrations. In addition, some essential metals can become toxic above certain concentration values in aquatic environments. The aquatic ecosystems of Cotonou channel and lake Nokoué receive the pollutants charges from the town cities of Cotonou, Abomey-Calavi and town hall of So Ava. The aim of this study is to analyze waters from Eighteen (18) stations identified in the two ecosystems (nine by ecosystem). The concentrations of magnesium (Mg), calcium (Ca), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), beryllium (Be), aluminum (Al), strontium (Sr), molybdenum (Mo), silver (Ag), tin (Sn), barium (Ba), platinum (Pt), mercury (Hg), thallium (Tl), lead (Pb), thorium (Th) and uranium (U) were measured after acid digestion of the water samples using the inductively coupled plasma source mass spectrometer (ICP-MS). The results of the analyses indicate an unequal distribution of metals in the different ecosystems. However, atypical concentrations were observed at some stations of the lake and the channel. Magnesium, calcium and manganese have very high values in Lake Nokoué respectively at Ganvié market station GAN_M (2990 ± 105 mg/L), Ganvié center, station GAN_C (4991 ± 177 mg/L) and Lake middle station MLak4 (10662 ± 17.03 μg/L). On the other hand, iron, aluminum and strontium have very high concentrations in the Cotonou Channel respectively at Agbato station AGB (5236 ± 103 and 8289 ± 519 μg/L) and at the estuary station EST (6118 ± 68 μg/L). The concentrations were compared to wells and cborehole waters in sixth neighborhood of Cotonou. We have used statistical analyzers such as MANOVA which have made it possible to classify the waters and metals in the ecosystems studied compared to groundwater and Well water waters. We use hierarchical clustering on principal components to identify similarities between stations based on metal concentration with R software packages “FactoMineR” and “factoextra”. In general, we can conclude that most of the metals have an anthropogenic source except strontium and major elements (Ca and Mg) which could respectively provide from marine waters and geochemical sources. 展开更多
关键词 METALS Water MANOVA r software Packages Nokoué Lake Cotonou Channel
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Mechanism of Duhuo Jisheng Decoction based on bioinformatics and network pharmacology in treating osteoporosis of kidney Yin deficiency
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作者 Jian-Wei Xiao Xu Cai +4 位作者 Xin-Min Huang Fen-Lian Guo Xin-Peng Chen Yi-Wei Hong Zhi-Zhong Ye 《Journal of Hainan Medical University》 2020年第15期59-63,共5页
Objective:To study the active ingredients,target and mechanism of Duhuo JiSheng Decoction for the treatment of osteoporosis by bioinformatics analysis and network pharmacology.Methods:The gene expression profile of GS... Objective:To study the active ingredients,target and mechanism of Duhuo JiSheng Decoction for the treatment of osteoporosis by bioinformatics analysis and network pharmacology.Methods:The gene expression profile of GSE56116 was acquired through the NCBI GEO database,and the software R was used for differential analysis.The Chinese medicine system pharmacology technology platform(TCMSP)was used to retrieve the chemical components,target genes of Duhuo,Fangfeng,Xixin,and Sangjisheng.The differential genes acquired from GSE56116 were intersected and analyzed by GO enrichment analysis and KEGG pathway to study the mechanism of Duhuo JiSheng Decoction.Results:A total of 33 active ingredients and 9 differential genes of Duhuo JiSheng Decoction for the treatment of Shengyin deficiency osteoporosis were screened.GO function enrichment analysis focuses on the regulation of intracellular signal transduction,calcium-mediated signaling,and steroid hormone mediated signaling.KEGG analysis showed that it was mainly concentrated in signal pathways such as P53 signal pathway,TNF signal pathway,and IL-17 signal pathway.Conclusion:Through bioinformatics and network pharmacological analysis,Duhuo JiShenng Decoction may exert therapeutic effects by acting on AR,IGFBP3,and FOS target genes. 展开更多
关键词 OSTEOPOrOSIS Bioinformatics analysis Network pharmacology Duhuo Jisheng Decoction r software
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A Stochastic Strategy for Optimizing the Cost of Systematic Screening of Some Diseases in a Situation of Insufficient Equipment
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作者 Lucien Zihindula Biguru 《Applied Mathematics》 2020年第12期1253-1274,共22页
In this work, we show that when there is insufficient equipment for detecting a disease whose prevalence is <em>t</em>% in a sub-population of size <em>N</em>, it is optimal to divide the <e... In this work, we show that when there is insufficient equipment for detecting a disease whose prevalence is <em>t</em>% in a sub-population of size <em>N</em>, it is optimal to divide the <em>N</em> samples into <em>n</em> groups of size r each and then, the value <img src="Edit_ce149849-3742-48fe-820b-02ccc0c92d83.bmp" alt="" /> allows systematic screening of all <em>N</em> individuals by performing less than <em>N</em> tests (In this expression, <img src="Edit_987eb236-a883-4894-ba2d-52bde5f35056.bmp" alt="" /> represents the floor function<sup>1</sup> of <em>x</em> ∈ R). Based on this result and on certain functions of the R software, we subsequently propose a probabilistic strategy capable of optimizing the screening tests under certain conditions. 展开更多
关键词 Stochastic Optimization Binomial Distribution Systematic Screening PrEVALENCE r software
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Climate Change and Its Impact on Brown Bear Distribution in Iran
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作者 Sahar Roshan Ara Sohrab Ashrafi +3 位作者 Roghayeh Garmaeepour Mohammad Zarrintab Nariman Askaripour Sorour Esfandeh 《Journal of Zoological Research》 2022年第1期1-11,共11页
Climate change is one of the threats in the recent century,affecting biodiversity directly and indirectly.Modeling the patterns of species distribution is one of useful tools for predicting the impacts of climate chan... Climate change is one of the threats in the recent century,affecting biodiversity directly and indirectly.Modeling the patterns of species distribution is one of useful tools for predicting the impacts of climate change on endangered species.Brown bear(Ursus arctos)plays an important role as a focal species in mountainous ecosystems.This study was aims to investigate the effects of future climate changes on the distribution of this species using an ensemble modeling method in R-software.For this purpose five algorithms including MAXENT,RF,MARS,GAM,GLM and BRT were used to predict the distribution of the species in the present climatic conditions as well as in the 2050s and 2070s.The results showed that temperature and precipitation were two main factors in the distribution of brown bears in Iran.Investigating the distribution of the brown bear in the future showed that suitability of its habitat will decrease in the western and central parts and increase in the northern parts.So a shift toward higher altitude will be expected for brown bear in the future.Therefore,in this condition it is imperative to upgrade the extent of protected areas for better conservation of brown bear. 展开更多
关键词 Iran Ursus arctos Species distribution modeling r software Predicting
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A bibliometric analysis using machine learning to track paradigm shifts and analytical advances in forest ecology and forestry journal publications from 2010 to 2022
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作者 Jin Zhao Liyu Li +4 位作者 Jian Liu Yimei Yan Qian Wang Chris Newman Youbing Zhou 《Forest Ecosystems》 SCIE 2024年第5期770-779,共10页
Forest habitats are critical for biodiversity,ecosystem services,human livelihoods,and well-being.Capacity to conduct theoretical and applied forest ecology research addressing direct(e.g.,deforestation)and indirect(e... Forest habitats are critical for biodiversity,ecosystem services,human livelihoods,and well-being.Capacity to conduct theoretical and applied forest ecology research addressing direct(e.g.,deforestation)and indirect(e.g.,climate change)anthropogenic pressures has benefited considerably from new field-and statistical-techniques.We used machine learning and bibliometric structural topic modelling to identify 20 latent topics comprising four principal fields from a corpus of 16,952 forest ecology/forestry articles published in eight ecology and five forestry journals between 2010 and 2022.Articles published per year increased from 820 in 2010 to 2,354 in 2021,shifting toward more applied topics.Publications from China and some countries in North America and Europe dominated,with relatively fewer articles from some countries in West and Central Africa and West Asia,despite globally important forest resources.Most study sites were in some countries in North America,Central Asia,and South America,and Australia.Articles utilizing R statistical software predominated,increasing from 29.5%in 2010 to 71.4%in 2022.The most frequently used packages included lme4,vegan,nlme,MuMIn,ggplot2,car,MASS,mgcv,multcomp and raster.R was more often used in forest ecology than applied forestry articles.R software offers advantages in script and workflow-sharing compared to other statistical packages.Our findings demonstrate that the disciplines of forest ecology/forestry are expanding both in number and scope,aided by more sophisticated statistical tools,to tackle the challenges of redressing forest habitat loss and the socio-economic impacts of deforestation. 展开更多
关键词 Forest ecology Forestry r software Structural topic modelling Machine learning Publication
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Multi-category diagnostic accuracy based on logistic regression
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作者 Jialiang Li Jason P.Fine Michael JPencina 《Statistical Theory and Related Fields》 2017年第2期143-158,共16页
We provide a detailed review for the statistical analysis of diagnostic accuracy in a multi-category classification task.For qualitative response variables with more than two categories,many traditional accuracy measu... We provide a detailed review for the statistical analysis of diagnostic accuracy in a multi-category classification task.For qualitative response variables with more than two categories,many traditional accuracy measures such as sensitivity,specificity and area under the ROC curve are no longer applicable.In recent literature,new diagnostic accuracy measures are introduced in medical research studies.In this paper,important statistical concepts for multi-category classification accuracy are reviewed and their utilities are demonstrated with real medical examples.We offer problem-based R code to illustrate how to perform these statistical computations step by step.We expect such analysis tools will become more familiar to practitioners and receive broader applications in biostatistics.Our program can be adapted to many classifiers among which logistic regression may be the most popular approach.We thus base our discussion and illustration completely on the logistic regression in this paper. 展开更多
关键词 Hypervolume under the rOC manifold multi-category classification correct classification probability net reclassification improvement integrated discrimination improvement marker evaluation r software
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