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Tree mycorrhizal associations determine how biodiversity,large trees,and environmental factors drive aboveground carbon stock in temperate forests
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作者 Yue Chen Zikun Mao +2 位作者 Jonathan A.Myers Jinghua Yu Xugao Wang 《Forest Ecosystems》 SCIE CSCD 2024年第4期448-456,共9页
Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these f... Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these factors depends on tree mycorrhizal associations,whereby large-tree effects may be driven by ectomycorrhizal(EM)trees,diversity effects may be driven by arbuscular mycorrhizal(AM)trees,and environment effects may depend on differential climate and soil preferences of AM and EM trees.To test this hypothesis,we used forest-inventory data consisting of over 80,000 trees from 631 temperate-forest plots(30 m×30 m)across Northeast China to examine how biodiversity(species diversity and ecological uniqueness),large trees(top 1%of tree diameters),and environmental factors(climate and soil nutrients)differently regulate aboveground carbon stocks of AM trees,EM trees,and AM and EM trees combined(i.e.total aboveground carbon stock).We found that large trees had a positive effect on both AM and EM tree carbon stocks.However,biodiversity and environmental factors had opposite effects on AM vs.EM tree carbon stocks.Specifically,the two components of biodiversity had positive effects on AM tree carbon stocks,but negative effects on EM tree carbon stocks.Environmental heterogeneity(mean annual temperature and soil nutrients)also exhibited contrasting effects on AM and EM tree carbon stocks.Consequently,for the total carbon stock,the positive large-tree effect far surpasses the diversity and environment effect.This is mainly because when integrating AM and EM tree carbon stock into total carbon stock,the opposite diversity-effect(also environment-effect)on AM vs.EM tree carbon stock counteracts each other while the consistent positive large-tree effect on AM and EM tree carbon stock is amplified.In summary,this study emphasized a mycorrhizal viewpoint to better understand the determinants of overarching aboveground carbon profile across regional forests. 展开更多
关键词 BIODIVERSITY Ecological uniqueness Environment heterogeneity Large trees Mycorrhizal associations Tree carbon stock
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Casual associations between blood metabolites and colon cancer
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作者 Ke-Yue Hu Yi-Quan Cheng +2 位作者 Zhi-Long Shi Fu-Peng Ren Gang-Feng Xiao 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期1995-2005,共11页
BACKGROUND Limited knowledge exists regarding the casual associations linking blood metabolites and the risk of developing colorectal cancer.AIM To investigate causal associations between blood metabolites and colon c... BACKGROUND Limited knowledge exists regarding the casual associations linking blood metabolites and the risk of developing colorectal cancer.AIM To investigate causal associations between blood metabolites and colon cancer.METHODS The study utilized a two-sample Mendelian randomization(MR)analysis to investigate the causal impact of 486 blood metabolites on colorectal cancer.The primary method of analysis used was the inverse variance weighted model.To further validate the results several sensitivity analyses were performed,including Cochran's Q test,MR-Egger intercept test,and MR robust adjusted profile score.These additional analyses were conducted to ensure the reliability and robustness of the findings.RESULTS After rigorous selection for genetic variation,486 blood metabolites were included in the MR analysis.We found Mannose[odds ratio(OR)=2.09(1.10-3.97),P=0.024],N-acetylglycine[OR=3.14(1.78-5.53),P=7.54×10^(-8)],X-11593-O-methylascorbate[OR=1.68(1.04-2.72),P=0.034],1-arachidonoylglycerophosphocholine[OR=4.23(2.51-7.12),P=6.35×10^(-8)]and 1-arachidonoylglycerophosphoethanolamine 4[OR=3.99(1.17-13.54),P=0.027]were positively causally associated with colorectal cancer,and we also found a negative causal relationship between Tyrosine[OR=0.08(0.01-0.63),P=0.014],Urate[OR=0.25(0.10-0.62),P=0.003],N-acetylglycine[0.73(0.54-0.98),P=0.033],X-12092[OR=0.89(0.81-0.99),P=0.028],Succinylcarnitine[OR=0.48(0.27-0.84),P=0.09]with colorectal cancer.A series of sensitivity analyses were performed to confirm the rigidity of the results.CONCLUSION This study showed a causal relationship between 10 blood metabolites and colorectal cancer,of which 5 blood metabolites were found to be causal for the development of colorectal cancer and were confirmed as risk factors.The other five blood metabolites are protective factors. 展开更多
关键词 METABOLITES Colon cancer Mendelian randomization Genome-wide association studies Casual
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Reform of the Irrigation Sector and Creation of Functional and Sustainable Irrigation Water Users Associations (AUEI) in Niger: Capitalization of the Experience of the Konni AHA
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作者 Saidou Abdoulkarimou Illou Mahamadou 《Agricultural Sciences》 2024年第2期209-229,共21页
During the 1980s, as part of a policy of liberalization, following budgetary cuts linked to the implementation of structural adjustment programs, management responsibilities for AHAs were transferred from ONAHA to coo... During the 1980s, as part of a policy of liberalization, following budgetary cuts linked to the implementation of structural adjustment programs, management responsibilities for AHAs were transferred from ONAHA to cooperatives concerned. Due to lack of financial resources, but also because of poor management, everywhere in Niger we are witnessing an accelerated deterioration of the irrigation infrastructure of hydro-agricultural developments. Institutional studies carried out on this situation led the State of Niger to initiate a reform of the governance of hydro-agricultural developments, by streng-thening the status of ONAHA, by creating an Association of Irrigation Water Users (AUEI) and by restructuring the old cooperatives. Indeed, this research aims to analyze the creation of functional and sustainable Irrigation Water User Associations (AUEI) in Niger in a context of reform of the irrigation sector, and based on the experience of the Konni AHA. It is based on a methodological approach which takes into account documentary research and the collection of data from 115 farmers, selected by reasoned choice and directly concerned by the management of the irrigated area. The data collected was analyzed and the results were analyzed using the systemic approach and the diagnostic process. The results show that the main mission of the AUEI is to ensure better management of water, hydraulic equipment and infrastructure on the hydro-agricultural developments of Konni. The creation of the Konni AUEI was possible thanks to massive support from the populations and authorities in the implementation process. After its establishment, the AUEI experienced a certain lethargy for some time due to the rehabilitation work of the AHA but currently it is functional and operational in terms of associative life and governance. Thus, the constraints linked to the legal system, the delay in the completion of the work, the uncertainties of access to irrigation water but also the problems linked to the change in mentality of certain ONAHA agents constitute the challenges that must be resolved in the short term for the operationalization of the Konni AUEI. 展开更多
关键词 Konni (Niger) Hydro-Agricultural Developments association of Irrigation Water Users GOVERNANCE
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The Development and Experience of American Pharmaceutical Industry Associations and Its Enlightenment to China
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作者 Zhang Yuanyuan Tian Lijuan 《Asian Journal of Social Pharmacy》 2024年第3期237-243,共7页
Objective To study the development history and current situation of pharmaceutical industry associations in the United State and to provide reference for China’s pharmaceutical industry associations.Methods Literatur... Objective To study the development history and current situation of pharmaceutical industry associations in the United State and to provide reference for China’s pharmaceutical industry associations.Methods Literature research and comparative study were used to investigate the development history and current situation of pharmaceutical associations in the United States.Then,their characteristics and experiences were summarized.Some countermeasures and suggestions were put forward for the existing problems of pharmaceutical associations in China.Results and Conclusion The institutional environment of pharmaceutical associations in the United States is relatively good,reflecting the characteristics of emphasizing process management and neglecting entrance management with and the help of public supervision.At the same time,the government advocates market competition by adhering to the market-oriented services for the public.American pharmaceutical industry associations have strong innovation capacity and perfect credit system.Drawing on the experience of pharmaceutical industry associations in the United States,China should strengthen the construction of pharmaceutical industry associations.Firstly,the supervision mechanism should be improved.Secondly,these associations should have good partnerships with the government and offer the public the best services.Finally,the fund-raising mechanism of pharmaceutical industry associations should be optimized to ensure the innovative development of the pharmaceutical industry. 展开更多
关键词 pharmaceutical industry association development history social co-governance
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Causal associations between inflammatory bowel disease and anxiety:A bidirectional Mendelian randomization study 被引量:1
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作者 Ying He Chun-Lan Chen +1 位作者 Jian He Si-De Liu 《World Journal of Gastroenterology》 SCIE CAS 2023年第44期5872-5881,共10页
BACKGROUND Anxiety is common in patients with inflammatory bowel disease(IBD),including those with ulcerative colitis(UC)and Crohn’s disease(CD);however,the causal relationship between IBD and anxiety remains unknown... BACKGROUND Anxiety is common in patients with inflammatory bowel disease(IBD),including those with ulcerative colitis(UC)and Crohn’s disease(CD);however,the causal relationship between IBD and anxiety remains unknown.AIM To investigate the causal relationship between IBD and anxiety by using bidirectional Mendelian randomization analysis.METHODS Single nucleotide polymorphisms retrieved from genome-wide association studies(GWAS)of the European population were identified as genetic instrument variants.GWAS statistics for individuals with UC(6968 patients and 20464 controls;adults)and CD(5956 patients and 14927 controls;adults)were obtained from the International IBD Genetics Consortium.GWAS statistics for individuals with anxiety were obtained from the Psychiatric Genomics Consortium(2565 patients and 14745 controls;adults)and FinnGen project(20992 patients and 197800 controls;adults),respectively.Inverse-variance weighted was applied to assess the causal relationship,and the results were strengthened by heterogeneity,pleiotropy and leave-one-out analyses.RESULTS Genetic susceptibility to UC was associated with an increased risk of anxiety[odds ratio:1.071(95%confidence interval:1.009-1.135),P=0.023],while genetic susceptibility to CD was not associated with anxiety.Genetic susceptibility to anxiety was not associated with UC or CD.No heterogeneity or pleiotropy was observed,and the leave-one-out analysis excluded the potential influence of a particular variant.CONCLUSION This study revealed that genetic susceptibility to UC was significantly associated with anxiety and highlighted the importance of early screening for anxiety in patients with UC. 展开更多
关键词 Inflammatory bowel disease ANXIETY Causal effect Mendelian randomization Genome-wide association studies
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Mechanistic associations between dietary patterns and colorectal cancer 被引量:4
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作者 Jing-Xiang Han Cheng-Fei Liu +5 位作者 Shao-Qiang Xu Ying-LeiCao Yan-Li Wang Tian Yao Fu-Bin Qiu He Huang 《Journal of Nutritional Oncology》 2023年第2期79-84,共6页
Colorectal cancer(CRC)is a common cancer with high morbidity and mortality rates.Its occurrence and development are determined by many factors,including genetics,the environment,lifestyle,and so on.The occurrence of C... Colorectal cancer(CRC)is a common cancer with high morbidity and mortality rates.Its occurrence and development are determined by many factors,including genetics,the environment,lifestyle,and so on.The occurrence of CRC is often accompanied by changes in the intestinal microenvironment.Numerous studies have focused on the association between dietary patterns,dietary components,and CRC now.This article reviews five different dietary patterns:the Western diet,the Mediterranean diet,the ketogenic diet,the Dietary Approaches to Stop Hypertension diet,and fasting,and themechanistic associations between their food components and CRC.The finding can provide a reference for further studies on the association between different dietary patterns and CRC and will help clinicians formulate reasonable and feasible dietary interventions. 展开更多
关键词 Colorectal cancer Dietary patterns Gut microbiota Mechanistic associations
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Prediction of miRNA-circRNA Associations Based on k-NN Multi-Label with Random Walk Restart on a Heterogeneous Network 被引量:2
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作者 Zengqiang Fang Xiujuan Lei 《Big Data Mining and Analytics》 2019年第4期261-272,共12页
Circular RNAs(circRNAs) play important roles in various biological processes, as essential non-coding RNAs that have effects on transcriptional and posttranscriptional gene expression regulation. Recently, many studie... Circular RNAs(circRNAs) play important roles in various biological processes, as essential non-coding RNAs that have effects on transcriptional and posttranscriptional gene expression regulation. Recently, many studies have shown that circRNAs can be regarded as micro RNA(miRNA) sponges, which are known to be associated with certain diseases. Therefore efficient computation methods are needed to explore miRNAcircRNA interactions, but only very few computational methods for predicting the associations between miRNAs and circRNAs exist. In this study, we adopt an improved random walk computational method, named KRWRMC, to express complicated associations between miRNAs and circRNAs. Our major contributions can be summed up in two points. First, in the conventional Random Walk Restart Heterogeneous(RWRH) algorithm, the computational method simply converts the circRNA/miRNA similarity network into the transition probability matrix;in contrast,we take the influence of the neighbor of the node in the network into account, which can suggest or stress some potential associations. Second, our proposed KRWRMC is the first computational model to calculate large numbers of miRNA-circRNA associations, which can be regarded as biomarkers to diagnose certain diseases and can thus help us to better understand complicated diseases. The reliability of KRWRMC has been verified by Leave One Out Cross Validation(LOOCV) and 10-fold cross validation, the results of which indicate that this method achieves excellent performance in predicting potential miRNA-circRNA associations. 展开更多
关键词 mirna-circrna associations heterogeneous network MULTI-LABEL random walk RESTART
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Genome-wide associations, polygenic risk, and Mendelian randomization reveal limited interactions between John Henryism and cynicism
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作者 Richard R Chapleau 《World Journal of Medical Genetics》 2023年第2期8-20,共13页
BACKGROUND John Henryism(JH)is a strategy for dealing with chronic psychological stress characterized by high levels of physical effort and work.Cynicism is a belief that people are motivated primarily by self-interes... BACKGROUND John Henryism(JH)is a strategy for dealing with chronic psychological stress characterized by high levels of physical effort and work.Cynicism is a belief that people are motivated primarily by self-interest.High scores on the JH scale and cynicism measures correlate with an increased risk of cardiovascular disease.High cynicism is also a hallmark of burnout syndrome,another known risk factor for heart disease.AIM To evaluate possible interactions between JH and cynicism hoping to clarify risk factors of burnout.METHODS We analyzed genetic and psychological data available from the Database of Genotypes and Phenotypes for genome-wide associations with these traits.We split the total available samples and used plink to perform the association studies on the discovery set(n=1852,80%)and tested for replication using the validation set(n=465).We used scikit-learn to perform supervised machine learning for developing genetic risk algorithms.RESULTS We identified 2,727,and 204 genetic associations for scores on the JH,cynicism and cynical distrust(CD)scales,respectively.We also found 173 associations with high cynicism,109 with high CD,but no associations with high JH.We also produced polygenic classifiers for high cynicism using machine learning with areas under the receiver operator characteristics curve greater than 0.7.CONCLUSION We found significant genetic components to these traits but no evidence of an interaction.Therefore,while there may be a genetic risk,JH is not likely a burnout risk factor. 展开更多
关键词 CYNICISM Burnout syndrome John Henryism Genome-wide association study Polygenic risk score MACHINE-LEARNING
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Prevalence of Hepatitis B and Associated Factors in the Garoua Central Prison, Cameroon: A Cross-Sectional Study
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作者 Mohamadou Abdou Galdima Adamou Dodo Balkissou +9 位作者 Guy Roger Nsenga Djapa Winnie Tatiana Bekolo Nga Gilles Aghoagni Antonin Wilson Ndjitoyap Ndam Ali Abas Mathurin Pierre Kowo Firmin Ankouane Andoulo Dominique Noah Noah Oudou Njoya Servais Albert Fiacre Eloumou Bagnaka 《Open Journal of Gastroenterology》 CAS 2024年第5期174-183,共10页
Introduction: Hepatitis B virus (HBV) infection is a major public health problem in Cameroon. Garoua city is the headquarters of the North Region of Cameroon, where the HBV prevalence is among the highest of the count... Introduction: Hepatitis B virus (HBV) infection is a major public health problem in Cameroon. Garoua city is the headquarters of the North Region of Cameroon, where the HBV prevalence is among the highest of the country. The aim of this study was to determine the prevalence of HBsAg carriage and associated factors among persons incarcerated in the Garoua Central Prison. Methods: It was a cross-sectional study conducted from July 1 to July 31, 2023 at the Garoua Central prison. We included all prisoners willing to participate in the study and who gave their verbal consent. We collected data using a pre-established data entry form and we used rapid test for blood screening for HBV surface antigen (HBs Ag) with ELISA confirmation. Data were analyzed using the R<sup>®</sup> software for Windows. After the univariate analysis, we selected associated variables to HBV infection with p-value p-value was set at 5%. Results: We included 1389 prisoners out of which 97.6% were male. The median age (IQR) of the study population was 28 (23 - 35) years. The median (IQR) duration of incarceration was 12 (6 - 26) months and the mean (±sd) number of incarcerations was 1.24 (±0.6). HBV prevalence was estimated at 14.8% (95% CI: 13.0 - 16.7). Upon uni- and multivariate analysis, no risk factor was significantly associated with viral hepatitis B infection in our study population. Conclusion: The prevalence of Hepatitis B was high in the Garoua Central Prison, but there were no additional risk factors for HBV infection. There is a need to include the Garoua Central Prison and by the way other prisons in the country in the chronic viral hepatitis care program. 展开更多
关键词 Hepatitis B PRISON associated factors Cameroon
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Associated Factors to Poor Blood Pressure Control in Hypertensives Followed Up at the Campus University Hospital of Lome (Togo)
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作者 Soulemane Pessinaba Yaovi Mignazonzon Afassinou +9 位作者 Wiyao Dieudonné Kaziga Komlavi Yayehd Kolani Lamboni Sélim Bolarinwa Mohamed Kpélafia Ekpe Togbossi Akpe Adzodo Machihude Pio Soodougoua Baragou Findibé Damorou 《World Journal of Cardiovascular Diseases》 CAS 2024年第6期374-380,共7页
Introduction: Hypertension is a real public health issue and its control is very difficult. We aim to determine the frequency of uncontrolled hypertension in hypertensive patients followed up as an outpatient at the c... Introduction: Hypertension is a real public health issue and its control is very difficult. We aim to determine the frequency of uncontrolled hypertension in hypertensive patients followed up as an outpatient at the campus university hospital of Lome (Togo) and to search for the associated factors. Methodology: The study was cross-sectional, descriptive and analytical, carried out from February (2022) to August 2022 in 260 hypertensive patients aged 22 years old, followed up (on an) as an outpatient for at least 3 months at the Lome University Hospital campus. A univariate then multivariate analysis were conducted in order to highlight the most common factors significantly linked to uncontrolled. Results: The mean age of hypertensives was 56.4 ± 12.7 years, the sex ratio (M/F) was 0.59. Prevalence of uncontrolled blood pressure was 42%. Associated Factors to poor blood pressure control in our study were age > 60 years (OR = 1.6 CI [1.17 - 2.50]), low socio-economic level (OR = 2.2 CI [1.96 - 4.33]), high cardiovascular risk level (OR = 3.1 CI [2.18 - 4.52]), non-adherence to regular blood pressure monitoring (OR = 3.3 CI [2.21 - 5.55]), low compliance to treatment (OR = 4.1 CI [2.33 - 6.76]) and a chronic renal failure (OR = 2.1 CI [1.21 - 3.10]). Conclusion: Nearly half of the hypertensives in our study had poorly controlled blood pressure by antihypertensive treatment medication. The factors of this poor control were age > 60 years, low socio-economic level, high or very high level of cardiovascular risk, low compliance to treatment, and renal failure. 展开更多
关键词 HYPERTENSION Poor Control associated factors TOGO
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Factors Associated with Renal Impairment in Patients on Tenofovir for Chronic Hepatitis B in Yaoundé (Cameroon)
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作者 Antonin Wilson Ndjitoyap Ndam Sonia Charlsia Ewuo Shu +6 位作者 Mahamat Maimouna Winnie Bekolo Nga Isabelle Dang Babagna Paul Talla Mathurin Kowo Firmin Ankouane Andoulo Gloria Enow Ashuntantang 《Open Journal of Gastroenterology》 CAS 2024年第1期18-30,共13页
Background: Tenofovir (TFV) is widely used to treat patients with hepatitis B virus (HBV) infection. But kidney abnormalities are the main concern using this drug. Few studies have described the renal impairment due t... Background: Tenofovir (TFV) is widely used to treat patients with hepatitis B virus (HBV) infection. But kidney abnormalities are the main concern using this drug. Few studies have described the renal impairment due to the TFV in chronic hepatitis B (CHB) in Sub-Saharan Africa. The objective was to evaluate factors associated with renal impairment observed in patients on TFV for CHB. Method: It was a hospital based cross sectional prospective study carried out from June 2023 to July 2023 in Yaoundé (Cameroon) and included any patient treated with TFV for CHB during at least a period of 6 months. For each participant, we collected in the medical report socio-demographic data, clinical data, baseline creatinine, treatment information (type of TFV which was Disoproxil Fumarate (TDF) or Alafenamide (TAF), duration). Then, we collected blood samples to measure serum creatinine and phosphate levels and urine dipstick analysis. Factors associated with renal impairment were assessed with the Odds Ratio. A p value of Results: A total of 60 participants were included. The median age was 44 years [36-55] and median duration of TFV therapy was 17.5 months [11.7-25.7]. The prevalence of reduced eGFR (Conclusion: Kidney function was impaired in some patients receiving TFV for CHB. It should be monitored, particularly after 36 months and for those receiving TDF prodrug. 展开更多
关键词 Chronic Hepatitis B TENOFOVIR Factors associated Renal Impairment Cameroon
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Depression and Suicidal Risk in HIV-Infected Adults at Brazzaville University Hospital: Prevalence and Associated Factors
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作者 Bienvenu Rolland Ossibi Ibara Tatia Adoua Doukaga +6 位作者 Alain M. Mouanga André Moukouma Martin Ekat Parfait Bintsindou Ella Angonga Pabota Princesse Benet Lebaho Bebene Damba Banzuzi 《Advances in Infectious Diseases》 CAS 2024年第1期24-33,共10页
Introduction: Highly active antiretroviral tritherapies have improved the quality of life of people living with HIV (PVVIH) and extended their life expectancy. However, the nervous system is faced with a neurotropic v... Introduction: Highly active antiretroviral tritherapies have improved the quality of life of people living with HIV (PVVIH) and extended their life expectancy. However, the nervous system is faced with a neurotropic virus that evolves chronically, sometimes creating neurological disorders directly or indirectly linked to stigmatization or therapeutic effects. Objective: to determine the prevalence of depression associated with suicidal risk (SR) and identify associated factors. Patients and method: This was a prospective descriptive and analytical study from January 1 to November 30, 2022, including all HIV-positive patients receiving or not receiving antiretroviral therapy. The study took place in the infectious diseases department of Brazzaville University Hospital. This department has an inpatient capacity of 36 beds, and an outpatient capacity of 25 patients per day, three times a week. This is the largest center for PVVIH in Brazzaville. The Patient Heath Questionnaire 9 (PHQ-9) was used to assess the degree of depression and suicidal risk. Therapeutic adherence was assessed using the Morisky questionnaire. Data were analyzed using SPSS version 23 software. Qualitative variables were expressed as numbers and percentages, and quantitative variables as means and standard deviations. Statistical tests were used according to their applicability criteria. For all tests, the significance threshold was set at 0.05. Results: A total of 150 patients were consulted, constituting the sample size. The prevalence of depression and suicidal risk was 32%. These patients had an average age of 42.83 ± 10.24 years, were female (n = 101;67.3%), Christian (n = 97;64%), single (n = 68;45.3%). Stigmatization (n = 75;50%) was the reason for attempted suicide. HIV was perceived as treatable (n = 103;68.7%), unlucky (n = 62;41.3%). Patients were WHO stage 1 (n = 105;70%). RS was present in 47 cases (31.3%). Factors associated with depression and suicidal risk were age (p = 0.000), residence (p = 0.028), suicide attempt (p = 0.000), desire to procreate (p = 0.000) and ARV (antiretrovirals) side effects (p Conclusion: The prevalence of depression and suicidal risk was high, in line with stigma and socio-economic conditions. The associated factors were in line with those identified in the literature. Mental health needs to be integrated into the overall care of people living with HIV. 展开更多
关键词 DEPRESSION Suicidal Risk HIV/AIDS PREVALENCE associated Factors
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A micro-crosslinked amphoteric hydrophobic association copolymer as high temperature-and salt-resistance fluid loss reducer for water-based drilling fluids
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作者 Jian Li Yu-Xi Ji +3 位作者 Xiao-Xiao Ni Kai-He Lv Xian-Bin Huang Jin-Sheng Sun 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1980-1991,共12页
During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtr... During ultradeep oil and gas drilling,fluid loss reducers are highly important for water-based drilling fluids,while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtration performance remains a challenge.Herein,a micro-crosslinked amphoteric hydrophobic association copolymer(i.e.,DADC)was synthesized using N,N-dimethyl acrylamide,diallyl dimethyl ammonium chloride,2-acrylamido-2-methylpropane sulfonic acid,hydrophobic monomer,and pentaerythritol triallyl ether crosslinker.Due to the synergistic effects of hydrogen bonds,electrostatic interaction,hydrophobic association,and micro-crosslinking,the DADC copolymer exhibited outstanding temperature-and salt-resistance.The rheological experiments have shown that the DADC copolymer had excellent shear dilution performance and a certain degree of salt-responsive viscosity-increasing performance.The DADC copolymer could effectively adsorb on the surface of bentonite particles through electrostatic interaction and hydrogen bonds,which bring more negative charge to the bentonite,thus improving the hydration and dispersion of bentonite particles as well as the colloidal stability of the drilling fluids.Moreover,the drilling fluids constructed based on the DADC copolymer exhibited satisfactory rheological and filtration properties(FLHTHP=12 m L)after aging at high temperatures(up to200℃)and high salinity(saturated salt)environments.Therefore,this work provided new insights into designing and fabricating high-performance drilling fluid treatment agents,demonstrating good potential applications in deep and ultradeep drilling engineering. 展开更多
关键词 Fluid loss reducer Temperature-and salt-resistance Hydrophobic association AMPHOTERIC Micro-crosslinking
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Epidemiological, Clinical Aspects and Factors Associated with Typical Gastroesophageal Reflux Disease in the General Population of Parakou, Republic of Benin
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作者 Saké Khadidjatou Tamou Sambo Bio Elie +3 位作者 Zinsou Jocelyne Abla Dovonou Comlan Albert Sehonou Jean Kodjoh Nicolas 《Open Journal of Gastroenterology》 CAS 2024年第2期41-58,共18页
Introduction: Gastroesophageal reflux disease (GERD) is a benign and chronic disease that can impair the quality of life. Objective: To study the epidemiological, clinical aspects and factors associated with typical G... Introduction: Gastroesophageal reflux disease (GERD) is a benign and chronic disease that can impair the quality of life. Objective: To study the epidemiological, clinical aspects and factors associated with typical GERD in the general population of Parakou in the Republic of Benin. Methods: This was a descriptive and analytical cross-sectional study with prospective data collection which took place from May 1, 2019 to June 30, 2019. The study population consisted of any subject aged at least 15 years and living in Parakou. Subjects aged at least 15 years, present on the day of the survey and having given their free and informed verbal consent were included. The Short form of QRS®(Reflux-Qual Short form) questionnaire and the “Hospital Anxiety and Depression” score were used to assess the quality of life and anxiety/depression, respectively. The sampling was probabilistic through a 2-stage cluster sampling. The variable of interest was the presence of GERD. Results: Out of 390 subjects surveyed, 28 had symptoms of typical GERD, representing a prevalence of 7.18%. The average age of these subjects was 27.11 ± 7.88 years. Fifteen subjects (53.57%) were male, giving a sex ratio of 1.15. Fourteen (50%) had a secondary level of education, 12 (42.86%) were pupils/students, 18 (64.29%) were single. The monthly income of 22 subjects (78.57%) was lower than the guaranteed interprofessional minimum wage (40,000 FCFA). The average duration of progression of symptoms was 15.89 ± 4.97 months. Symptoms occurred less than twice a week in 22 subjects (78.57%). The clinical manifestations were both diurnal and nocturnal in 12 subjects (42.86%). None of the 28 subjects with GERD had clinical warning signs. Asthma, diabetes, consumption of high fat or spice foods, carbonated drinks, non-steroidal anti-inflammatory drugs, alcoholic beverages and tobacco were statistically associated with the occurrence of GERD. Each of the 28 subjects had at least one associated factor. A significant impair in quality of life was observed in 27 patients (96.43%). Conclusion: Typical GERD is relatively common in the general population of Parakou in the Republic of Benin. It often affects young males. Among the risk factors identified, the most common are carbonated drinks, spicy meals and diabetes. GERD significantly impairs quality of life. Raising awareness about the disease and its associated factors is necessary among the general population. 展开更多
关键词 Gastroesophageal Reflux Disease EPIDEMIOLOGY General Population associated Factors Quality of Life Parakou
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Short, Medium, and Long-Term Stroke Mortality in Libreville and Associated Factors
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作者 Grass Aurelle Mambila Matsalou Jennifer Nyangui Mapaga +9 位作者 Pupchen M. Gnigone Minka’a Pagbe Michael Chermine Mboumba Mboumba Christian Allognon Mahutondji Aissata Ibrahima Camara Annick A. Nsounda Nelly Diouf Mbourou Michel-Arnaud Saphou-Damon Elsa Ayo Bivigou Philomene Kouna Ndouongo 《Neuroscience & Medicine》 2024年第1期39-50,共12页
Strokes are common around the world and especially in sub-Saharan Africa. They are responsible for severe sequelae and the majority of deaths. In Gabon, no study on stroke mortality has been conducted. Objective: To d... Strokes are common around the world and especially in sub-Saharan Africa. They are responsible for severe sequelae and the majority of deaths. In Gabon, no study on stroke mortality has been conducted. Objective: To determine short, medium, long-term mortality and factors associated with long-term stroke mortality. Method: Our study took place in the Neurology Department of the University Hospital Center of Libreville (UHCL). It was a historical cohort study with descriptive and analytical purposes covering the period from June 1 to August 31, 2018 and taking into account hospitalized patients from January 1, 2013 to December 31, 2017. We conducted a comprehensive systematic recruitment of patients with stroke, 18 years old and more, and had been agreed to give information. We included all patients meeting the inclusion criteria. The data was gathered using Epi-Info 7 software. The CHI-2 test was used for the comparison of frequencies and the Student’s test, for comparison of means. Multivariate analysis with logistic regression allowed us to look for factors associated with long-term mortality.  A result was statistically significant for a p 0.05 value. Results: At 3 months, 28 patients (18.1%) died, at 6 months thirty-one patients or 20.1% died. At 5 years old, fifty-three patients or 34.4% had died. The factors associated with long-term mortality, if the lost of sight were all alive were tobacco (p = 0.01) and stroke (p = 0.008). If all those who were lost to sight had died, no factor was associated with 5-year mortality. Conclusion: Stroke mortality must not be taken for granted, it can be underestimated because of the large number of lost sight. Measures must be put in place to strengthen post-stroke monitoring. . 展开更多
关键词 STROKE MORTALITY associated Factors Libreville
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Study of Factors Associated with Knowledge, Attitudes and Practices Regarding Rabies in the Commune of Niakhéne in Senegal, in 2022
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作者 Boubacar Gueye Martial Coly Bop +7 位作者 Ndéye Marième Diagne Khadija Barro Cheikh Tacko Diop Alioune Badara Tall Papa Gallo Sow Mountaga Dia Abdoul Aziz Ndiaye Ousseynou Ka 《Open Journal of Epidemiology》 2024年第1期180-197,共18页
Introduction: Rabies is a serious disease, as it is always fatal, but it can be prevented by sero-vaccination. It is a neglected tropical disease endemic in Asia and Africa. The aim of this study was to assess knowled... Introduction: Rabies is a serious disease, as it is always fatal, but it can be prevented by sero-vaccination. It is a neglected tropical disease endemic in Asia and Africa. The aim of this study was to assess knowledge, attitudes and practices regarding rabies and to determine the factors associated with them among people aged 18 and over in the commune of Niakhène. Methods: This was a cross-sectional, descriptive and analytical survey of subjects aged 18 and over living in the commune of Niakhène. A sample of 300 individuals was drawn from a two-stage cluster survey stratified by age and sex. Bivariate analysis was performed using association tests. Results: The mean age of respondents was 35.3 ± 16.9 years. It was noted that 67% (201) of respondents had a good knowledge of rabies. The results showed that 7.3% (22) of respondents owned a dog. Of the 278 people who did not own a dog, 78.4% (218) said they would have vaccinated their dog if they had had one. It should be noted that 83.7% (251) of respondents said they would go to a health facility if an animal bit them. None of the dog owners had vaccinated their dogs against rabies. Of the 41 people exposed to rabies, 39% went to a health facility. The age and education of the respondents had statistically significant associations with knowledge of rabies. Respondents’ age and education were statistically significantly related to whether they had vaccinated a domestic dog. The age, education and economic well-being quintile of respondents’ households had statistically significant associations with the use of a health facility in the event of being bitten or scratched by an animal vector. The education of respondents who had been bitten by an animal vector was statistically significantly associated with the use of a health facility. Conclusion: It would be imperative for human and animal health authorities to collaborate in a “One Health” approach in order to increase knowledge and promote the adoption of good practices in rabies prevention. 展开更多
关键词 RABIES KNOWLEDGE ATTITUDES PRACTICES associated Factors Senegal
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Spatial compartmentalization and temporal stability of associated microbiota in Pacific oyster Crassostrea gigas
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作者 Qiang FU Zichao YU +4 位作者 Junyan ZHAO Lei GAO Ning KONG Lingling WANG Linsheng SONG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1348-1358,共11页
The Pacific oyster Crassostrea gigas,one of the most exploited molluscs in the world,has suffered from massive mortality in recent decades,and the occurrence mechanisms have not been well characterized.In this study,t... The Pacific oyster Crassostrea gigas,one of the most exploited molluscs in the world,has suffered from massive mortality in recent decades,and the occurrence mechanisms have not been well characterized.In this study,to reveal the relationship of associated microbiota to the fitness of oysters,temporal dynamics of microbiota in the gill,hemolymph,and hepatopancreas of C.gigas during April 2018-January 2019 were investigated by 16 S rRNA gene sequencing.The microbiota in C.gigas exhibited tissue heterogeneity,of which Spirochaetaceae was dominant in the gill and hemolymph while Mycoplasmataceae enriched in the hepatopancreas.Co-occurrence network demonstrated that the gill microbiota exhibited higher inter-taxon connectivity while the hemolymph microbiota had more modules.The richness(Chao 1 index)and diversity(Shannon index)of microbial community in each tissue showed no significant seasonal variations,except for the hepatopancreas having a higher richness in the autumn.Similarly,beta diversity analysis indicated a relatively stable microbiota in each tissue during the sampling period,showing relative abundance of the dominant taxa exhibiting temporal dynamics.Results indicate that the microbial community in C.gigas showed a tissue-specific stability with temporal dynamics in the composition,which might be essential for the tissue functioning and environmental adaption in oysters.This work provides a baseline microbiota in C.gigas and is helpful for the understanding of host-microbiota interaction in oysters. 展开更多
关键词 Pacific oyster associated microbiota spatial compartmentalization temporal stability
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Distribution and dynamics of niche and interspecific association of dominant phytoplankton species in the Feiyun River basin,Zhejiang,China
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作者 Shengnan ZHU Zengchuan DONG +6 位作者 Guobin FU Shujun WU Jinyu MENG Weilin LIU Yupeng LIU Xun CUI Yuejiao ZHOU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1157-1172,共16页
To investigate the dominant species and interspecific association in the phytoplankton community of the Feiyun River basin in Zhejiang Province,East China,the main stream and the Shanxi Zhaoshandu Reservoir in the dow... To investigate the dominant species and interspecific association in the phytoplankton community of the Feiyun River basin in Zhejiang Province,East China,the main stream and the Shanxi Zhaoshandu Reservoir in the downstream were chosen as the study area,for which 22 sampling sites were designated.Sampling was conducted in September 2021,January,May,and July 2022.Phytoplankton species were identified from both quantitative samples and in-vivo observations.Phytoplankton was quantified by direct counting.Results show that there were 98 species belonging to 6 phyla and 78 genera.In addition,to clarify the niches of the dominant phytoplankton species and their interspecific association,the dominance index was calculated,and a comprehensive analysis was conducted including niche width,niche overlap value,ecological response rate,overall association,chi-square test,and the stability.The phytoplankton community exhibited characteristics of a Cyanobacteria-Chlorophyta-Diatom type community,showing higher diversity in spring and lower diversity in summer.Among 11 dominants phytoplankton species from 3 phyla,both frequency and dominance degree varied seasonally,of which Microcystis sp.was the dominant species in Spring,Autumn,and Winter.The niche widths of the dominant species ranged from 0.234 to 0.933,and were categorized into three groups.The niche overlap values of the 11 dominant species ranged from 0.359 to 0.959,exhibiting significant seasonal differences-highest in winter followed by autumn,spring,and summer in turn.The overall correlation among dominant species in all four seasons revealed a non-significant negative association,resulting in an unstable community structure.A significant portion(84.2%)of species pairs displayed positive associations,suggesting a successional pattern where Diatoms dominated while other dominant species shared resources and space.Despite this pattern,stability measurements indicated that the dominant species community remained unstable.Therefore,careful monitoring is recommended for potential water environment issues arising from abnormal proliferation of dominant species in the watershed during winter.This research built a theoretical foundation with a data support to the early warning of eutrophication and provided a reference for water resources management in similar watersheds along the eastern coast of China. 展开更多
关键词 PHYTOPLANKTON dominant species NICHE interspecific association Feiyun River basin
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Associated Factors with Early Sexual Intercourse among In-School Adolescents in Brazzaville
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作者 Aymar Pierre Gildas Oko Dumez Ngoma +4 位作者 Judicaël Kambourou Eryx Darius Mbou Essie Neli Yvette Ngakengni Lynda Tchidjo Ngamo Georges Marius Moyen 《Open Journal of Pediatrics》 2024年第5期898-907,共10页
Background: Early sexual intercourse (ESI) is a global public health problem. In Congo, associated factors with ESI have been under-studied. Objective: To analyse factors associated with early sexual intercourse among... Background: Early sexual intercourse (ESI) is a global public health problem. In Congo, associated factors with ESI have been under-studied. Objective: To analyse factors associated with early sexual intercourse among in-school adolescents in Brazzaville. Method: A cross-sectional analytic study with three-stage random sampling was carried out from March 2 to June 2, 2022 in Brazzaville secondary and high schools. Adolescents in the selected schools were interviewed about their sexual and social behaviour, and their family and school environment. Multivariate analysis using logistic regression was used to identify factors associated with ESI. The significance level of the p-value was set at 5% and the confidence interval at 95%. Results: Of a total of 1100 adolescents surveyed, 800 (72.7%) had ESI, 98% of them were female. The main reason for early initiation of sexual intercourse was curiosity (81.8%). Non-use of condoms and multiple sexual partnerships were noted respectively in 98.7% and 68.7% of adolescents who had experienced ESI. Female gender (p Conclusion: The prevalence of ESI is high, and the factors identified in this study may help to reduce it. 展开更多
关键词 associated Factors Early Sex Adolescents BRAZZAVILLE
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Prevalence and Associated Factors of Postpartum Depression: A Study Conducted in Health Centres in Dakar (Senegal)
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作者 Sokhna Seck Momar Camara +7 位作者 Racky Wade Kane Djeynaba Bassine Baldé El Hadj Makhtar Bâ Adama Koundoul Idrissa Bâ Ibrahima Ndiaye Papa Lamine Faye Aida Sylla 《Open Journal of Psychiatry》 2024年第1期45-66,共22页
Introduction: Postpartum depression is the most common psychiatric disorder affecting women in the perinatal period. According to the WHO, it affects 10% - 15% of women who have just given birth. In Africa, and partic... Introduction: Postpartum depression is the most common psychiatric disorder affecting women in the perinatal period. According to the WHO, it affects 10% - 15% of women who have just given birth. In Africa, and particularly in Senegal, epidemiological studies focusing exclusively on postpartum depression are rare or non-existent. For this reason, we conducted this screening study on postpartum depression to assess the socio-demographic characteristics and associated factors. Methods: This was a prospective cross- sectional study with descriptive and analytical aims. It was carried out in the twelve Dakar referral health centres during the period August 2021 to June 2022. Results: At the end of our survey we had recruited one hundred and twenty-two (122) participants with a PPD prevalence rate of 25.41%. The most common age group was 24 - 29 years. 40% of the participants were of Fulani ethnicity, followed by Wolof. Married women made up 93% of the sample. The school enrolment rate was 89%. Most participants were not in paid employment. Domestic violence was present in 14% of couples. 28% of mothers reported experiencing a stressful life event during their pregnancy. 22% of the women had a chronic medical condition, of which 55% had high blood pressure. 1% of the women reported a personal psychiatric history and 5% a family psychiatric history. Most women had between two and four healthy living children. The pregnancy was unwanted in 17% of cases and 12% of participants had a complication. 6% were dissatisfied with the quality of their antenatal care. The caesarean section rate was 18%. In terms of associated factors, eight factors were identified in a bivariate analysis: single marital status, lack of support from partner, domestic violence, conflict with in-laws, and the occurrence of a stressful life event during pregnancy, the presence of a personal medical history, lack of satisfaction with pregnancy follow-up, and mode of delivery by caesarean section. Conclusion: Our study showed the high prevalence of PPD (25.41%) and identified associated risk factors. Among these factors, two were strongly associated with postpartum depression: lack of satisfaction with pregnancy care and experiencing a stressful life event during pregnancy. Systematic screening or identification of risk factors during pregnancy is necessary for comprehensive treatment based on a biopsychosocial approach. 展开更多
关键词 Postpartum Depression PREVALENCE associated Factors Senegal
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