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Marital Status as a Moderator:Exploring the Relationship between Social Engagement and Depressive Symptoms in China’s Older Adult Population
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作者 Jianlun Wu Yaping Ye +4 位作者 Man Zhang Ruichen Cong Yitao Chen Pengfei Yu Qing Guo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第10期1142-1157,共16页
Objective This study aims to explore the complex relationship between social engagement and depressive symptoms among older adults in China,focusing particularly on the moderating role of marital status.Methods This s... Objective This study aims to explore the complex relationship between social engagement and depressive symptoms among older adults in China,focusing particularly on the moderating role of marital status.Methods This study used data from the latest Chinese Longitudinal Healthy Longevity Survey(CLHLS).The analysis used the latent class analysis to delineate personality clusters and hierarchical linear regression,supplemented by the PROCESS macro,to investigate the effects of social engagement and marital status on depressive symptoms.Results The analysis encompassed 7,789 respondents(mean age:82.53[s=11.20]years),with 54%female.The personality analysis categorized participants into four clusters,with the majority(77.60%)classified as Confident Idealists,who exhibited the lowest levels of depressive symptoms.Hierarchical linear regression analysis yielded several significant findings:Higher levels of social engagement were significantly associated with fewer depressive symptoms(t=-7.932,P<0.001,B=-0.463).Marital status was a significant factor;married individuals reported fewer depressive symptoms compared to their unmarried counterparts(t=-6.368,P<0.001,B=-0.750).There was a significant moderating effect of marital status on the relationship between social engagement and depressive symptoms(t=-2.092,P=0.037,B=-0.217).Conclusion This study demonstrates that,among Chinese older adults,both social engagement and marital status significantly influence depressive symptoms.Higher social engagement,particularly in other activities like doing household chores,gardening,reading newspapers or books,and playing cards or Mahjong,is associated with fewer depressive symptoms,especially among married individuals. 展开更多
关键词 Social engagement Depressive symptoms Marital status MODERATOR Older adults
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Antibody Levels and Infection Status of Pertussis in the Population under Pertussis Resurgence in Guangxi in 2018:A Cross-Sectional Survey
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作者 Liang Liang Qiuyun Deng +6 位作者 Lili Deng Jinghang Wei Shiyi Chen Yizhi Wei Yuyan Ma Yue Qin Wei Liu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第6期628-638,共11页
Objective Pertussis cases have increased markedly since 2018 in Guangxi.The aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident population.Method A total of 10,215 s... Objective Pertussis cases have increased markedly since 2018 in Guangxi.The aim of this study was to evaluate antibody levels and the infection status of pertussis in the resident population.Method A total of 10,215 serum samples from residents were collected from August-November 2018 and tested for anti-pertussis IgG and toxin IgG using the enzyme-linked immunosorbent assay(ELISA).Results Of the collected samples,1,833(17.94%)tested positive for anti-pertussis IgG,with the median concentration of 16.06 IU/mL.Antibody level<10 IU/mL accounted for more than 60%in children under 4 years of age,but declined with age,whereas the percentages of the other three levels(10-40,40-50,and≥50 IU/mL)increased almost with age(P<0.001).Moreover,7,924 samples were selected for anti-pertussis toxin IgG,of which 653(8.24%)tested positive(≥40 IU/mL)with the median concentration of 5.89 IU/mL,and 204 participants(2.56%)had recent pertussis infection(≥100 IU/mL).Among the different age groups,the highest rates of positivity and recent infection were observed at 11-20 years of age,the lowest positivity rate at 5 years of age,and the lowest recent infection rate at 4 years of age(P<0.001,P=0.005,respectively).Conclusion The survey results showed that all age groups in Guangxi lacked immunity against pertussis,which was one of the main factors contributing to the resurgence of pertussis in 2018.In addition,the prevalence of pertussis is relatively high in Guangxi,and its incidence is seriously underestimated,especially in adolescents and adults. 展开更多
关键词 Pertussis resurgence Anti-pertussis IgG Anti-pertussis toxin IgG Antibody level Infection status
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Changes of China’s Status in the Global System and Its Influencing Factors:A Multiple Contact Networks Perspective
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作者 LIU Jian LIU Jibin +2 位作者 YANG Qingshan CAI Sikai LIU Jie 《Chinese Geographical Science》 SCIE CSCD 2024年第2期265-279,共15页
Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on cou... Clarifying China’s position in the global system is an important logical basis for developing national diplomacy.Although much research has been done on China’s development status,most studies have been based on country comparisons or institutional en-vironment.In today’s networked era in which the global economy,trade,personnel,and information are closely connected,studies on China’s global position and its status changes and influencing factors in multiple contact networks are still insufficient.In this study,from the perspective of diverse global contact networks,we constructed economic,cultural,and political influence indices to explore the changes and influencing factors on China’s status in the global system from 2005 to 2018.The results show that during the study period,China’s global influence in the fields of economic ties,cultural exchanges,and political contacts increased significantly,but its influ-ence in the fields of cultural exchanges and political contacts lagged far economic ties.The pattern of China’s economic influence on various economies around the world has shown a transformation from an‘upright pyramid’to an‘inverted pyramid’structure.The proportion of these economies in low-influence zones has decreased from more than 60%in 2005 to less than 20%in 2018.China’s cultural and political influence on various economies around the world has increased significantly;however,for the former,the percentage of high-influence areas is still less than 20%,whereas for the latter the percentage of these economies in medium-and high-influence areas is still less than 50%.Analyses such as a scatter plot matrix show that geographical proximity,economic globalization,close cooperation with developing countries,and a proactive and peaceful foreign policy are important factors in improving China’s status in the diverse global network system. 展开更多
关键词 global system economic ties cultural exchanges political contacts multiple contact networks China’s status
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Elucidating the structure-activity relationship of Cu-Ag bimetallic catalysts for electrochemical CO_(2) reduction
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作者 Qining Huang Lili Wan +1 位作者 Qingxuan Ren Jingshan Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期345-351,I0009,共8页
Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential fo... Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential for catalyst design.Herein,we prepared two Cu-Ag bimetallic catalysts with Ag nanoparticles attached to the top or the bottom of Cu nanowires.When tested in a flow cell,the Cu-Ag catalyst with Ag nanoparticles on the bottom achieved a faradaic efficiency of 54%for ethylene production,much higher than the catalyst with Ag nanoparticles on the top.The catalysts were further studied in the H-cell and zero-gap MEA cell.It was found that placing the two metals in the intensified reaction zone is crucial to triggering the tandem reaction of bimetallic catalysts.Our work elucidates the structure-activity relationship of bimetallic catalysts for CO_(2) reduction and demonstrates the importance of considering both catalyst structures and cell characteristics to achieve high activity and selectivity. 展开更多
关键词 Electrochemical CO_(2)reduction Bimetallic catalyst CU-AG Structure-activity relationship
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The Relationship between Father-Love Absence and Loneliness:Based on the Perspective of the Social Functionalist Theory and the Social Needs Theory
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作者 Yaping Zhou He Zhong +1 位作者 Xiaojun Li Yanhui Xiang 《International Journal of Mental Health Promotion》 2024年第2期139-148,共10页
Fathers play an important role in adolescents’development,which is significant for their development and influences their mental health,including feeling of loneliness.However,the effects and mechanisms of father-lov... Fathers play an important role in adolescents’development,which is significant for their development and influences their mental health,including feeling of loneliness.However,the effects and mechanisms of father-love absence on individual loneliness are not clear.Based on the social functionalist theory and the social needs theory,this study examines the influence of individual fatherlove absence on loneliness and its underlying mechanisms.A questionnaire survey was administered to 319 junior high school students and 1,476 high school students.The results showed that adolescents with father-love absence had higher levels of loneliness,and that father-love absence affected loneliness levels through mediating pathways of individual gratitude,peer relationships,and gratitude to peer relationships.This study not only confirms the negative effects of father-love absence on adolescents’loneliness,but also explains the mediate roles of individual gratitude and peer relationships.It enriches the theoretical system related to family education and has important theoretical and practical implications for further interventions on adolescents’mental health from the perspective of fatherless parenting. 展开更多
关键词 Father-love absence LONELINESS GRATITUDE peer relationships
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PCB CT Image Element Segmentation Model Optimizing the Semantic Perception of Connectivity Relationship
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作者 Chen Chen Kai Qiao +2 位作者 Jie Yang Jian Chen Bin Yan 《Computers, Materials & Continua》 SCIE EI 2024年第11期2629-2642,共14页
Computed Tomography(CT)is a commonly used technology in Printed Circuit Boards(PCB)non-destructive testing,and element segmentation of CT images is a key subsequent step.With the development of deep learning,researche... Computed Tomography(CT)is a commonly used technology in Printed Circuit Boards(PCB)non-destructive testing,and element segmentation of CT images is a key subsequent step.With the development of deep learning,researchers began to exploit the“pre-training and fine-tuning”training process for multi-element segmentation,reducing the time spent on manual annotation.However,the existing element segmentation model only focuses on the overall accuracy at the pixel level,ignoring whether the element connectivity relationship can be correctly identified.To this end,this paper proposes a PCB CT image element segmentation model optimizing the semantic perception of connectivity relationship(OSPC-seg).The overall training process adopts a“pre-training and fine-tuning”training process.A loss function that optimizes the semantic perception of circuit connectivity relationship(OSPC Loss)is designed from the aspect of alleviating the class imbalance problem and improving the correct connectivity rate.Also,the correct connectivity rate index(CCR)is proposed to evaluate the model’s connectivity relationship recognition capabilities.Experiments show that mIoU and CCR of OSPC-seg on our datasets are 90.1%and 97.0%,improved by 1.5%and 1.6%respectively compared with the baseline model.From visualization results,it can be seen that the segmentation performance of connection positions is significantly improved,which also demonstrates the effectiveness of OSPC-seg. 展开更多
关键词 Semantic segmentation PCB non-destructive testing mask image modeling connectivity relationship
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Influence of the continuing COVID-19 epidemic on sleep quality and psychological status of healthcare workers in private institutions
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作者 Man-In Ho Zhe-Hao Wu +11 位作者 Yu-Ying Chen Weng-Io Leong Jue Wang Hua Zhou Zi-Tuo Wu Ying-Qi Mao Jia-An Du Yi Zheng Yi Yu Paulo Do Lago Comandante Li-Li Yu Qi-Biao Wu 《World Journal of Psychiatry》 SCIE 2024年第10期1495-1505,共11页
BACKGROUND On January 22,2020,Macao reported its first case of coronavirus disease 2019(COVID-19)infection.By August 2021,the situation had escalated into a crisis of community transmission.In response,the government ... BACKGROUND On January 22,2020,Macao reported its first case of coronavirus disease 2019(COVID-19)infection.By August 2021,the situation had escalated into a crisis of community transmission.In response,the government launched a recruitment campaign seeking assistance and services of healthcare workers(HCWs)from the private sector throughout Macao.These participants faced concerns about their own health and that of their families,as well as the responsibility of maintaining public health and wellness.This study aims to determine whether the ongoing epidemic has caused them physical and psychological distress.AIM To examine the influence of COVID-19 on the sleep quality and psychological status of HCWs in private institutions in Macao during the pandemic.METHODS Data were collected from December 2020 to January 2022.Two consecutive surveys were conducted.The Pittsburgh Sleep Quality Index(PSQI)scale,Self-Rating Anxiety Scale(SAS),and Self-Rating Depression Scale(SDS)were employed as investigation tools.RESULTS In the first-stage survey,32%of HCWs experienced a sleep disorder,compared to 28.45%in the second-stage survey.A total of 31.25%of HCWs in the first-stage survey and 28.03%in the second had varying degrees of anxiety.A total of 50.00%of HCWs in the first-stage survey and 50.63%in the second experienced varying degrees of depression.No difference in PSQI scores,SAS scores,or SDS scores were observed between the two surveys,indicating that the COVID-19 epidemic influenced the sleep quality and psychological status of HCWs.The negative influence persisted over both periods but did not increase remarkably for more than a year.However,a positive correlation was observed between the PSQI,SAS,and SDS scores(r=0.428-0.775,P<0.01),indicating that when one of these states deteriorated,the other two tended to deteriorate as well.CONCLUSION The sleep quality,anxiety,and depression of HCWs in private institution in Macao were affected by the COVID-19 epidemic.While these factors did not deteriorate significantly,the negative effects persisted for a year and remained noteworthy. 展开更多
关键词 COVID-19 Healthcare workers Sleep quality ANXIETY DEPRESSION Psychological status
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Modern pollen-vegetation relationships along altitudinal vegetation belts in the Leigong Mountain of southwestern China
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作者 LI Shuming ZHAO Wenwei +7 位作者 WEI Lisi REN Weihe GU Qinran WU Siqi JI Yang YANG Ziteng ZHUANG Rui CHEN Chunzhu 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2249-2262,共14页
Understanding the distribution,dispersal,and correlation of modern pollen with vegetation in mountainous regions is essential for establishing accurate modern analogs for fossil pollen records.This study,conducted in ... Understanding the distribution,dispersal,and correlation of modern pollen with vegetation in mountainous regions is essential for establishing accurate modern analogs for fossil pollen records.This study,conducted in Leigong Mountain on the YunnanGuizhou Plateau of southwestern China,involved the collection of 35 surface soil samples from diverse vegetation communities along an elevational gradient ranging from 1210 to 1875 meters.The results reveal a close correspondence between modern pollen assemblages and vegetation zones.Principal Component Analysis(PCA)results indicate that pollen assemblages can effectively distinguish between subtropical montane evergreen broad-leaved forest(SEBF)and subtropical montane deciduous broadleaved forest(SDBF).However,both SEBF and SDBF show significant overlap with subtropical montane evergreen-deciduous broad-leaved mixed forest(SEMF).Detrended Correspondence Analysis(DCA)results clearly distinguish the three vegetation zones,and the first axis of DCA shows a significant positive correlation with elevation(p<0.01,R=0.48).Discriminant Analysis(DA)successfully assigns 94.4%of the modern pollen samples to their respective vegetation zones.Pollen taxa such as Impatiens,Astertype,and Rosaceae exhibit significant indicative capabilities for the SEBF zone,effectively distinguishing this vegetation zone from others.Pinus and Alnus display overrepresentation in the Leigong Mountain region,while Quercus(D,deciduous-type)and Poaceae exhibit high representation in the SEBF zone.In the SEBF zone,both pollen diversity and richness are the lowest.Our study reveals the complex relationship between the richness and diversity of pollen and vegetation.The diversity and richness of tree and shrub pollen are found to be lower than those of the corresponding plants.The pollen-vegetation relationship elucidated in this study serves as a critical reference for reconstructing ancient environments from fossil pollen retrieved in this region. 展开更多
关键词 Modern pollen assemblages Pollenvegetation relationship Pollen diversity and richness Leigong Mountain Southwestern China
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Investigation on the Current Status and Effects of Online Course Learning for Nursing Students
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作者 Wei LIU Yuan ZHAO +3 位作者 Ye WANG Dan HOU Lirong JIA Weiguang YUE 《Medicinal Plant》 2024年第5期76-78,共3页
[Objectives]To explore the current situation and effects of online learning from the perspective of students,as well as the learning dynamics,and to explore the online teaching methods.It is possible to put forward re... [Objectives]To explore the current situation and effects of online learning from the perspective of students,as well as the learning dynamics,and to explore the online teaching methods.It is possible to put forward relevant suggestions for the problems presented by online teaching,find effective teaching methods,and explore appropriate online teaching methods.[Methods]The nursing students of the 2020,2021,and 2022 grades of Chengde Nursing Vocational College were selected as the research subjects.A self-made questionnaire survey method was adopted.The questionnaire had 5 items and 44 questions:3 questions on personal information,9 questions on the teacher level,12 ques-tions on the student level,7 questions on the technical level,and 13 questions on online learning satisfaction.[Results]In the process of on-line teaching,the cooperation between family and school can be carried out to give full play to the important role of family supervision in online learning and other education,which is conducive to maintaining the discipline of online courses on the Internet,increasing the online learning effect of students,and avoiding the temptation of the Internet to the greatest extent.In the process,we should increase students'self-control in online learning,help students shape realistic goals,and thus improve the effect of online learning.Technical level:increase information-based teaching,enrich teaching content,and introduce virtual simulation software to simulate clinical operations,so as to increase students’interest and enthusiasm in learning.[Conclusions]This study is expected to provide a certain reference for the smooth and efficient development of online teaching and online learning skills. 展开更多
关键词 Online teaching Learning status SATISFACTION
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The Risk Role of Defeat on the Mental Health of College Students:A Moderated Mediation Effect of Academic Stress and Interpersonal Relationships
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作者 Ruiyang Han Tingting Xu +1 位作者 Yin Shi Wuyi Liu 《International Journal of Mental Health Promotion》 2024年第9期731-744,共14页
Background:College students face significant academic and physiological changes,making them more susceptible to psychological issues such as depression,self-injury,and suicidal ideation.Feelings of defeat can exacerba... Background:College students face significant academic and physiological changes,making them more susceptible to psychological issues such as depression,self-injury,and suicidal ideation.Feelings of defeat can exacerbate these risks by increasing academic stress.However,interpersonal relationships can moderate the impact of academic stress on students’mental health.Utilizing the presage–process–product model,this study aims to empirically investigate how feelings of defeat influence depression,self-injury,and suicidal ideation among college students.Additionally,it explores the mediating role of academic stress and the moderating role of various types of interpersonal relationships.Methods:A total of 1612 college students(750 females,862 males,mean age=19.64±0.62 years)were recruited through cluster sampling.Data were collected via offline questionnaires administered by a trained psychology teacher and a postgraduate student,ensuring high reliability with two examiners per class.Latent profile analysis(LPA)was used to examine the impact of defeat on mental health outcomes,while mediation analysis was conducted to assess the roles of academic stress and interpersonal relationships.Results:1.Defeat is identified as a significant risk factor for mental health issues among college students;2.Four distinct patterns of interpersonal relationships were identified:the interpersonal-relationship risk group,the father–child-relationship high-risk group,the general interpersonal-relationship group,and the superior interpersonal-relationship group;3.Academic stress partially mediates the relationship between defeat and mental health issues such as depression,self-injury,and suicidal ideation;4.Different interpersonal relationship models moderate the impact of academic stress on depression and suicidal ideation.Conclusion:Defeat is a significant risk factor for mental health problems in college students.Academic stress partially mediates the negative impact of defeat on mental health,while patterns of interpersonal relationships moderate this impact.Effective early prevention and intervention should focus on monitoring students’stress levels and fostering warm,positive parent–child relationships. 展开更多
关键词 Student mental health DEFEAT academic stress interpersonal relationships mediation test
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Impact of US Financial Sanctions on the Dollar's International Status
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作者 Ma Xue 《Contemporary International Relations》 2024年第4期49-68,共20页
In 2022,the United States stepped up its sanctions on Russia.Most notably,it restricted the flow of the Russian Central Bank's foreign exchange(forex)assets,using financial administrative power as a source of stra... In 2022,the United States stepped up its sanctions on Russia.Most notably,it restricted the flow of the Russian Central Bank's foreign exchange(forex)assets,using financial administrative power as a source of strategic leverage.This move should have reduced the appeal of US dollar assets but in reality has not accelerated as expected the decline of the greenback as a store of value.The US dollar's share of global forex reserves increased instead of decreased during 2022 and 2023.Despite the rise of economic costs caused by tightened US financial sanctions,countries that recognize the geopolitical role of the United States have further accepted the dollar's international status;their continued willingness to live with the dollar's“security premium”has given a fillip to the US dollar in the short term,boosting its appeal as a reserve currency.Meanwhile,de-dollarization of forex reserves has yet to reach a sufficient scale,thus falling short of significantly challenging the dollar's reign.From a longer-term perspective,as economic and security conditions shift,countries that accept the dollar's international role or seek de-dollarization may change their choices.As a result,four possible scenarios may arise:(i)the preeminence of the US dollar remains unthreatened;(ii)the international monetary system splits into blocs;(iii)the international monetary system fragments;and(iv)the dollar loses its throne.The author believes that the last scenario is the most likely outcome. 展开更多
关键词 de-dollarization international status of the US dollar national security US financial sanctions
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The Effects of Different Feeding Practices on the Nutritional Status of Infants below 12 Months Old in the Kumba 1 Sub-Division
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作者 Gillian Nkeudem Asoba Fidelis Sameh Ebong +3 位作者 Samuel Metuge Etchu Kaptai Tabe Teh Rene Ning Sumbele Irene Ngole 《Food and Nutrition Sciences》 CAS 2024年第5期336-350,共15页
Appropriate feeding practices are important during infancy for good health, growth and development of infants and children. WHO revised its earlier recommendation of Exclusive Breastfeeding (EBF) of infants from 4 to ... Appropriate feeding practices are important during infancy for good health, growth and development of infants and children. WHO revised its earlier recommendation of Exclusive Breastfeeding (EBF) of infants from 4 to 6 months of age to EBF until about 6 months of age, with the addition of complementary foods thereafter. This recommendation confirms that breast milk alone is sufficient to meet infants’ nutritional requirements for the first 6 months of life. The main objective of this study was to investigate the effect of various feeding practices on the Nutritional status of infants 0 - 12-month-old in the Kumba 1 Sub-Division. A descriptive cross-sectional study was conducted from December 2019 to August 2020. A total of 341 nursing mothers and their infants 0 - 12 months of age were recruited. Socio-demographic factors and the different feeding habits of the children were assessed using a semi-structured questionnaire. Nutritional status was assessed using anthropometric measurements. The overall proportion of infants who exclusively breastfed for 6 months was 69.2% and those who were mix-fed were 30.8% in the study area. The overall prevalence of malnutrition in the population was 61.0%. Among the malnourished children, 53.1% were underweight, 19.6% were wasted and 10.0% were stunted. Though not significant, the prevalence of wasting (21.0%) and underweight (58.3%) was higher among Mix-Fed (MF) children when compared to their EBF counterparts. Feeding practices affected the nutritional status of the infants. Underweight and wasting were observed among infants on Complementary Feeding (CF), although some exclusively breast-fed infants were stunted. Hence, nursing mothers should try as much as possible to practice EBF as recommended by WHO and can practice CF when the child is above six months. 展开更多
关键词 Exclusive Breastfeeding Complementary Feeding Feeding Practices INFANTS MALNUTRITION Nutritional status UNDERWEIGHT Wasted STUNTING
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Growth, Population Parameters and Stock Status of Sarotherodon galilaeus in Samandeni Reservoir, Burkina Faso
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作者 Nomwine Da Raymond Ouedraogo +1 位作者 Mahamoudou Minoungou Adama Oueda 《Open Journal of Ecology》 2024年第4期257-273,共17页
Mango tilapia, Sarotherodon galilaeus is one of the most caught fish species in the Samandeni multi-species fishing sites of which, few data on its biology and exploitation are available. The study aimed to Assess the... Mango tilapia, Sarotherodon galilaeus is one of the most caught fish species in the Samandeni multi-species fishing sites of which, few data on its biology and exploitation are available. The study aimed to Assess the stock status of S. galilaeus. Sampling was conducted from March, 2021 to February 2022 based on commercial fish catches to analyze growth parameters, first sexual maturity size and harvest status of the stock. A total of 572 specimens including 297 females and 275 males were examined. The stock assessment was performed by using the Length based Bayesian method of Biomass (LBB) and that of growth by the ELEFAN method. The growth parameters showed a seasonality of growth and females appeared to grow faster than males. On the other hand, males had a greater asymptotic length than females. Results on the estimated length of fish at first maturity showed that females firstly reached the maturity compared to males. The relative biomass (B/B<sub>0</sub>) estimated for the stock was higher than the relative biomass that produces maximum sustainable yield (B<sub>MSY</sub>/B<sub>0</sub>) indicating healthy biomass. In addition, the length at first sexual maturity was less than the length at the first catch, indicating the absence of overfishing of growth. In addition, extending the study to the various stocks of the reservoir would be important for the sustainable management of the Samandeni high economic fishing area. 展开更多
关键词 GROWTH Stock status Sarotherodon galilaeus Samandeni Reservoir MATURITY
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Current Status and Challenges of the Water and Soil Conservation in Hotan County, Xinjiang
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作者 Junhui WANG Lei ZHANG 《Meteorological and Environmental Research》 2024年第3期72-76,共5页
In order to thoroughly analyze the current status and challenges faced by the water and water conservation in Hotan County of Xinjiang,the use situation of water resources,the effectiveness and shortcomings of water a... In order to thoroughly analyze the current status and challenges faced by the water and water conservation in Hotan County of Xinjiang,the use situation of water resources,the effectiveness and shortcomings of water and soil conservation work in the region are reviewed.Hotan County has achieved several remarkable achievements in the soil and water conservation project,daily management and maintenance,and ecological restoration projects.Some measures,such as terrace construction,slope protection engineering,and the construction of windproof and sandwood belts,have also had a positive impact on improving the quality of surface water resources while effectively curbing soil erosion.But there are also lack of operating policy detailed rules and implementation plans,and planning and design of some water and soil conservation projects lack of integrity and systematicness,application and promotion of new technologies,and soil loss management and ecological recovery effect assessment lack of comprehensive assessment indicators and methods.It has caused some water and soil conservation works to fail to be effectively implemented.In this regard,countermeasures and suggestions are put forward,such as strengthening the planning and management of water and soil conservation,promoting the technology and measures of water and soil conservation,increasing investment and funding support,and strengthening publicity education and personnel training. 展开更多
关键词 Hotan County Water and soil conservation status CHALLENGE
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The Strange Relationship between the Momentum of a Photon Emitted from an Electron and the Momentum Acquired by the Electron
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作者 Koshun Suto 《Journal of Applied Mathematics and Physics》 2024年第7期2652-2664,共13页
In quantum mechanics, the energy of a hydrogen atom is minimized when the principal quantum number n is 1. However, the author has previously pointed out that the hydrogen atom has a state where n=0. An electron in th... In quantum mechanics, the energy of a hydrogen atom is minimized when the principal quantum number n is 1. However, the author has previously pointed out that the hydrogen atom has a state where n=0. An electron in the state where n=0has zero rest mass energy. However, a hydrogen atom has an energy level even lower than the n=0state. This is hard to accept from the standpoint of common sense. Thus, the author has previously pointed out that an electron at the energy level where n=0has zero energy because the positive energy mec2and negative energy −mec2cancel each other out. This paper elucidates the strange relationship between the momentum of a photon emitted when a hydrogen atom is formed by an electron with such characteristics, and the momentum acquired by the electron. 展开更多
关键词 Einstein’s Energy-Momentum relationship Energy-Momentum relationship in a Hydrogen Atom Momentum of a Photon Momentum of a Electron Negative Energy Specific to the Electron Dark Matter
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Research on the strain gauge mounting scheme of track wheel force measurement system based on high-speed wheel/rail relationship test rig
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作者 Yuanwu Cai Bo Chen Chongyi Chang 《Railway Sciences》 2024年第4期503-513,共11页
Purpose-This paper aims to analyze the stress and strain distribution on the track wheel web surface and study the optimal strain gauge location for force measurement system of the track wheel.Design/methodology/appro... Purpose-This paper aims to analyze the stress and strain distribution on the track wheel web surface and study the optimal strain gauge location for force measurement system of the track wheel.Design/methodology/approach-Finite element method was employed to analyze the stress and strain distribution on the track wheel web surface under varying wheel-rail forces.Locations with minimal coupling interference between vertical and lateral forces were identified as suitable for strain gauge installation.Findings-The results show that due to the track wheel web’s unique curved shape and wheel-rail force loading mechanism,both tensile and compressive states exit on the surface of the web.When vertical force is applied,Mises stress and strain are relatively high near the inner radius of 710 mm and the outer radius of 1110mmof the web.Under lateral force,high Mises stress and strain are observed near the radius of 670mmon the inner and outer sides of the web.As the wheel-rail force application point shifts laterally toward the outer side,the Mises stress and strain near the inner radius of 710 mm of the web gradually decrease under vertical force while gradually increasing near the outer radius of 1110 mm of the web.Under lateral force,the Mises stress and strain on the surface of the web remain relatively unchanged regardless of the wheel-rail force application point.Based on the analysis of stress and strain on the surface of the web under different wheel-rail forces,the inner radius of 870 mm is recommended as the optimal mounting location of strain gauges for measuring vertical force,while the inner radius of 1143 mm is suitable for measuring lateral force.Originality/value-The research findings provide valuable insights for determining optimal strain gauge locations and designing an effective track wheel force measurement system. 展开更多
关键词 Track wheel High-speed wheel/rail relationship test rig Instrumented wheelset Strain gauge Finite element
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Floristic Diversity and Conservation Status of Guineo-Congolese Species in Southeastern Cameroon: The Case of the Gari-Gombo Communal Forest
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作者 Boris Nyeck Valery Noiha Noumi +3 位作者 Nicole Maffo Maffo Victor Awe Djongmo Cedric Djomo Chimi Louis Zapfack 《Open Journal of Forestry》 2024年第1期87-97,共11页
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 rig... 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. 展开更多
关键词 Communal Forest Conservation status Cameroon Floristic Diversity
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Study on The Current Status and Progress of Clinical Application of Ciprofol
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作者 Lihua Liu Xiaokun Shen 《Journal of Clinical and Nursing Research》 2024年第6期166-170,共5页
Ciprofol,as a new type of short-acting intravenous anesthetic drug,belongs to the category of gamma-aminobutyric acid(GABA)receptor agonists.Its unique chemical structure,through the introduction of the cyclopropyl gr... Ciprofol,as a new type of short-acting intravenous anesthetic drug,belongs to the category of gamma-aminobutyric acid(GABA)receptor agonists.Its unique chemical structure,through the introduction of the cyclopropyl group in the isopropyl side chain of propofol,constructs a new type of chiral molecule,which significantly enhances the spatial effect,and improves the affinity for GABA receptors.Its pharmacological properties are characterized by high potency,rapid onset of action,rapid recovery,low accumulation,and minimal adverse reactions.Therefore,it has a wide range of applications in various endoscopic diagnostic and therapeutic operations,ICU sedation,and general anesthesia.In this paper,the related knowledge of ciprofol and the development of clinical application research are comprehensively sorted out and synthesized,to provide a solid theoretical basis for the rational application of ciprofol in clinical practice.At the same time,the future research direction of ciprofol will also be prospected to provide valuable references for research in related fields. 展开更多
关键词 Ciprofol Clinical application Application status Research progress
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Research on the Evaluation System of Community Daycare Center Planning and Implementation from the Perspective of Subject-Object Relationships
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作者 Tijin Gui 《Journal of Architectural Research and Development》 2024年第3期117-127,共11页
Through literature review,we found that evaluations of urban planning implementation often focus narrowly on either the subject(stakeholders)or the object(projects),while micro-level aspects such as site selection and... Through literature review,we found that evaluations of urban planning implementation often focus narrowly on either the subject(stakeholders)or the object(projects),while micro-level aspects such as site selection and construction are primarily considered within the context of planning implementation.There is insufficient research on the evaluation of implementation.Community daycare centers play a crucial role in the community home care model,yet there is relatively little research on their usage efficiency,satisfaction levels,and spatial evaluation of planning implementation.Based on the theoretical understanding of the human environment,including the subject,object,and their interactions,an evaluation system for the planning and implementation of community day care centers was constructed,incorporating subjective evaluation,objective evaluation,and comparative analysis. 展开更多
关键词 Subject-object relationship Daycare center Planning implementation Evaluation system
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Effect of Early Enteral Nutrition Combined with Probiotics on the Nutritional Status of Patients with Severe Craniocerebral Injury
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作者 Huaying Guan 《Journal of Clinical and Nursing Research》 2024年第5期260-265,共6页
Objective:To observe the effect of early enteral nutrition combined with probiotics on the nutritional status of patients with severe craniocerebral injury.Methods:Thirty-five patients with severe craniocerebral injur... Objective:To observe the effect of early enteral nutrition combined with probiotics on the nutritional status of patients with severe craniocerebral injury.Methods:Thirty-five patients with severe craniocerebral injury were divided into the study group(17 patients)and the control group(18 patients)according to the method of a randomized numerical table;both groups of patients started enteral nutrition via nasogastric tube within 24–48 hours after admission to the hospital,and probiotics were given in addition to the study group.Hemoglobin,total plasma protein,albumin,prealbumin,cholinesterase,fasting blood glucose,and other indexes were monitored before and early morning after enteral nutrition support,and upper arm circumference(AC),triceps skinfold thickness(TSF),and upper arm muscle circumference(AMC)were measured,and gastrointestinal response and time to first defecation of the patients were observed and compared with GCS score.Results:The hemoglobin,serum albumin,prealbumin,cholinesterase,and total plasma protein levels in the study group were significantly higher and fasting blood glucose levels were significantly lower than those in the control group after treatment(P<0.05).The incidence of reflux and constipation in the study group was lower than that in the control group,and the time to first defecation was shorter than that in the control group(P<0.05).After treatment,AC,TSF,and AMC were higher in the study group than in the control group(P<0.05).GCS scores were significantly higher in both groups after treatment,but the trend was more pronounced in the study group(P<0.05).Conclusion:Compared with simple enteral nutrition,enteral nutrition combined with probiotics can better correct metabolic disorders after heavy craniocerebral injury and improve the nutritional status of patients. 展开更多
关键词 Heavy craniocerebral injury Early enteral nutrition PROBIOTICS Nutritional status
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