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Establishment of Diagnostic Reference Levels for Childhood Head CT in the District of Abidjan in Côte d’Ivoire
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作者 Koutoua Joseph Anouan Raïssa-Michelle Kabas +1 位作者 Jean-Paul Kouao Aboubakar Sidiki Diabaté 《World Journal of Nuclear Science and Technology》 2025年第1期45-52,共8页
Computed tomography is an indispensable X-ray imaging modality used to diagnose numerous pathologies, but it can also involve the delivery of high ionizing radiation doses harmful to the health of patients. This study... Computed tomography is an indispensable X-ray imaging modality used to diagnose numerous pathologies, but it can also involve the delivery of high ionizing radiation doses harmful to the health of patients. This study aims to survey the level of radiation doses delivered to child patients during head exams in CT imaging to set up the Dosimetric Reference Levels (DRLs), a routine dose optimization tool, based on data acquired at the University Hospital of Angré (UHA), the University Hospital of Treichville (UHT) and the Polyclinic Hospital Farah (Farah) for optimizing procedures in Ivorian hospitals. Prospectively performed on 334 CT images of 186 child patients, this study was carried out on CT systems such as Hitachi Scenaria, Sinovision Insitum, and Philips Incisive used respectively at UHA, UHT and Farah. Children’s scan data were classified into four age bands: vol or dose-length product as DLP) value, whatever the hospital, increases with respect to the age of child patients. Based on the 75th percentile of the whole dose distributions, the DRLs of the CTDIvol is 54.37 mGy whatever the age groups and those of the DLP with respect to age bands are 1224.55 mGy∙cm, 1414.06 mGy∙cm, 1632.24 mGy.cm and 1544.57 mGy∙cm, respectively. The averaged values of CTDIvol and DLP smaller than the corresponding DRLs values suggest that practices in our three facilities are optimized. However, comparing our results with those from different international studies, we see that the CTDIvol and DLP values obtained in the present work are higher. These results suggest additional surveys to ensure our DRLs values and efforts from radiologists, imaging technicians and medical physicists to strengthen clinical procedures for the radiation protection of children undergoing CT scans in Côte d’Ivoire. 展开更多
关键词 Computed Tomography Childhood Head Imaging Radiation Protection Diagnostic Reference levels
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Diagnostic Reference Levels, Protection of Patients and the Environment against Harmful Effects of X-Rays: Practice of Pediatric Radiology in Six General Reference Hospitals of the Kongo Central Province, DRC
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作者 Minga Barthelemy Bope Kwete Pembi Francy Pembi +13 位作者 Luwaya Ndombasi Blanchard Ipende Lansikub Jean Sokomoy Nankwa Joséphine Mukadi Mukadi Jules Thomas Byeka Mukambilwa Dorksin Kapia Patrice Milambo Binkedi Ngoma Richard Omombo Ngongo Timothée Mbiango Mabanza Francine Kafinga Ketibula Charly Nkwadi Katolo Adolphe Ngongo Mulemba Tchite Aya Nkole Benjamin Kafinga Luzolo Emery Masandi Milondo Alphonse 《Journal of Biosciences and Medicines》 2025年第1期47-59,共13页
The purpose of this research was to evaluate radiological safety in pediatric radiology in hospitals in the Kongo Central province of the DRC. To this end, we surveyed a convenience sample of 50 health professionals, ... The purpose of this research was to evaluate radiological safety in pediatric radiology in hospitals in the Kongo Central province of the DRC. To this end, we surveyed a convenience sample of 50 health professionals, including 10 radiologists working in the hospitals covered by the survey, to assess the practice of pediatric radiology and the degree of compliance with radiation protection principles for the safety of children and the environment. We collected radiophysical parameters to calculate entrance doses in pediatric radiology in radiology departments to determine the dosimetric level by comparison with the diagnostic reference levels of the International Commission on Radiological Protection (ICRP). All in all, we found that in Kongo Central in the DRC, many health personnel surveyed reported that more than 30% of requested radiological examinations are not justified. Also, after comparing the entrance doses produced in the surveyed departments with those of the International Commission on Radiological Protection (ICRP), a statistically significant difference was found in pediatric radiology between the average doses in five out of six surveyed departments and those of the ICRP. Therefore, almost all of the surveyed departments were found to be highly irradiating in children, while excessive X-ray irradiation in children can have significant effects due to their increased sensitivity to radiation. Among the risks are: increased cancer risks, damage to developing cells, potential genetic effects, and neurological effects. This is why support for implementing radiation protection principles is a necessity to promote the safety of patients and the environment against the harmful effects of X-rays in conventional radiology. 展开更多
关键词 Diagnostic Reference levels (DRLs) Radiation Protection Environment and Pediatric Radiology
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Concepts and Misconceptions in Climate Change Risk Assessment: Considerations for Sea Level Rise and Extreme Precipitation Risk
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作者 Efthymia Koliokosta 《Journal of Geoscience and Environment Protection》 2025年第1期178-214,共37页
Flood extremes due to sea level rise and extreme precipitation are expected to increase in frequency and intensity. However, despite the need for accurate climate change risk assessment, significant misconceptions in ... Flood extremes due to sea level rise and extreme precipitation are expected to increase in frequency and intensity. However, despite the need for accurate climate change risk assessment, significant misconceptions in key risk terms, including vulnerability and impact, could lead to risk miscalculations. These misconceptions around risk concepts derive from the lack of risk terms’ standardization and the gaps in an integrated and widely accepted methodology for assessing climate change risks. Risk assessment frameworks should follow the specialties of each element/sector it is applied on and the special features of each climate hazard. Also, risk assessment matrix should not follow specific design settings but it should better follow the needs of each study, so as to optimize the understanding of each risk. Through an extensive literature review, this is the first paper that identifies gaps, inconsistencies and misuses of climate risk concepts and suggests specific systemization and standardization of risk terms definitions. Finally, it develops a climate change risk assessment framework and matrix, focusing on sea level rise and extreme precipitation, which could be widely implemented in risk assessment of all elements at sea level rise and extreme precipitation risk. 展开更多
关键词 Risk Concept Risk Misconceptions IMPACT VULNERABILITY Climate Change Sea level Rise Extreme Precipitation Risk Assessment Risk Ranking
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Impact of nurse and beloved family member’s voice stimulus on the level of consciousness and physiological parameters in comatose patients
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作者 Smritikana ADAK Rashmimala PRADHAN +3 位作者 Sujyotsna JENA Subhalaxmi PRADHAN Lulup Kumar SAHOO Mamata SWAIN 《Journal of Integrative Nursing》 2025年第1期33-41,共9页
Objective:The objective of this study was to compare the effect of nurse and beloved family member’s recording voice on consciousness and physical parameters in patients with coma state.Materials and Methods:A random... Objective:The objective of this study was to compare the effect of nurse and beloved family member’s recording voice on consciousness and physical parameters in patients with coma state.Materials and Methods:A randomized control trial parallel group design was conducted among 45 comatose patients divided into two intervention groups,i.e.nurse voice stimulus group,receiving nurses voice with standard care,family members voice stimulus group receiving their beloved family member voice with standard care and one control group receiving only standard care in medicine intensive care unit.The intervention was provided three times a day,each lasting 5 min for 7 days in addition to standard care.Repeated measure analysis of variance and independent t-test were used to compare within and between groups,respectively.Results:The study found significant differences in Glasgow coma scale(GCS)scores within both the nurse(F=2.78,P=0.042)and family member(F=10.27,P=0.0001)voice stimulus groups over 7 days.Comparing GCS scores between intervention groups showed significant variations before(P=0.028),during(P=0.047),and after(P=0.036)the intervention on day 7.Comparing GCS scores between the family members’voice stimulus group and the control group,significant changes were observed on days 5 and 7(P=0.043,0.030,0.030,and 0.014,0.012,0.012)before,during,and after the intervention.Conclusions:The use of beloved family members’voices proved more effective in elevating the patients’level of consciousness compared to both the nurse voice stimulus group and the control group. 展开更多
关键词 Comatose patients level of consciousness physiological parameters voice stimulus
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Comparison of different severity scores in correlating hemoglobin levels with the severity of hepatic decompensation: An observational study
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作者 Himayat Ullah Sarwat Huma +13 位作者 Ghulam Yasin Muhammad Ashraf Nafisa Tahir Qazi Tahir Uddin Hossam Shabana Mostafa A R Hussein Abdulrahman Shalaby Mohammad Mossaad Alsayyad Ashraf Said Ali Farahat Hani Ismail Hamed Hazem Sayed Ahmed Ayoub Mohammed S Imam Essam Elmahdi 《World Journal of Hepatology》 2025年第1期55-63,共9页
BACKGROUND Chronic liver disease is a growing global health problem,leading to hepatic decompensation characterized by an array of clinical and biochemical complic-ations.Several scoring systems have been introduced i... BACKGROUND Chronic liver disease is a growing global health problem,leading to hepatic decompensation characterized by an array of clinical and biochemical complic-ations.Several scoring systems have been introduced in assessing the severity of hepatic decompensation with the most frequent ones are Child-Pugh score,model of end-stage liver disease(MELD)score,and MELD-Na score.Anemia is frequently observed in cirrhotic patients and is linked to worsened clinical outcomes.Although studies have explored anemia in liver disease,few have investigated the correlation of hemoglobin level with the severity of hepatic decompensation.AIM To determine the relationship between hemoglobin levels and the severity of decompensated liver disease and comparing the strength of this correlation using the Child-Pugh,MELD,and MELD-Na scores.METHODS This cross-sectional study was conducted at a tertiary care hospital with 652 decompensated liver disease patients enrolled in the study.Data was collected on demographics,clinical history,and laboratory findings,including hemoglobin levels,bilirubin,albumin,prothrombin time(international normalized ratio),sodium,and creatinine.The Child-Pugh,MELD,and MELD-Na scores were calculated.Statistical analysis was performed using Statistical Package for the Social Sciences version 26,and correlations between hemoglobin levels and severity scores were assessed using Spearman's correlation coefficient.RESULTS The study included 405 males(62.1%)and 247 females(37.9%)with an average age of 58.8 years.Significant inverse correlations were found between hemoglobin levels and Child-Pugh,MELD,and MELD-Na scores(P<0.01),with the MELD scoring system being the strongest correlator among all.One-way analysis of variance revealed significant differences in hemoglobin levels across the severity groups of each scoring system(P=0.001).Tukey's post hoc analysis confirmed significant internal differences among each severity group.CONCLUSION Understanding the correlation between hemoglobin and liver disease severity can improve patient management by offering insights into prognosis and guiding treatment decisions. 展开更多
关键词 Hepatic decompensation Hemoglobin level Chronic liver disease Child Turcotte Pugh score Model of end-stage liver disease score Model of end-stage liver disease-Na score
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英国T-Level资格证书制度的发展动向及其镜鉴
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作者 屈玲 《职教通讯》 2025年第1期86-96,共11页
近年来,英国为了促进职业技术教育改革,构建了一个与学徒制并行的职业教育学习项目——T-Level资格证书制度。为保障T-Level项目的顺利运行,英国参照A-Level学习项目的成功经验系统规划了T-Level的运行方案。英国T-Level能规范、有效、... 近年来,英国为了促进职业技术教育改革,构建了一个与学徒制并行的职业教育学习项目——T-Level资格证书制度。为保障T-Level项目的顺利运行,英国参照A-Level学习项目的成功经验系统规划了T-Level的运行方案。英国T-Level能规范、有效、有序地运行,不仅有赖于英国对T-Level改革目标、开发原则、教育机构、课程结构、师资来源和考核评价等方面的科学规划,更离不开英国法定监管机构对T-Level实施全过程的质量保障监管。基于英国T-Level的成功推广与运行,我国可以借鉴以下三点经验:制定“工学结合”的职业教育课程,拓宽职教学生的进修渠道,完善职业教育课程评价监管机制。 展开更多
关键词 职业技术教育改革 T-level 质量保证
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英国T-Level课程改革对我国职业教育课程改革的启示
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作者 邵瑶 《宁波职业技术学院学报》 2025年第2期1-6,共6页
分析了英国T-Level课程改革的实效与经验,探讨了其对我国职业教育课程改革的启示。基于英国首批T-Level学习者调查结果,总结了T-Level在提升学生学业水平、职业技能、综合素养,以及丰富学生发展路径等方面的显著成效。T-Level成功的关... 分析了英国T-Level课程改革的实效与经验,探讨了其对我国职业教育课程改革的启示。基于英国首批T-Level学习者调查结果,总结了T-Level在提升学生学业水平、职业技能、综合素养,以及丰富学生发展路径等方面的显著成效。T-Level成功的关键在于其课程设计中与行业需求的深度对接、实践与理论的有机结合以及灵活的学术与职业转换路径。结合英国T-Level课程改革经验,建议我国职业教育课程改革应建设面向企业需求的职业教育课程、构建普职融通的职业教育课程体系、注重职业技能与综合素养均衡发展,以培养真正高质量、高素质的技术人才。 展开更多
关键词 英国T-level课程改革 实效与经验 学习者调查 职业教育改革 启示
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Aspect-Level Sentiment Analysis of Bi-Graph Convolutional Networks Based on Enhanced Syntactic Structural Information
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作者 Junpeng Hu Yegang Li 《Journal of Computer and Communications》 2025年第1期72-89,共18页
Aspect-oriented sentiment analysis is a meticulous sentiment analysis task that aims to analyse the sentiment polarity of specific aspects. Most of the current research builds graph convolutional networks based on dep... Aspect-oriented sentiment analysis is a meticulous sentiment analysis task that aims to analyse the sentiment polarity of specific aspects. Most of the current research builds graph convolutional networks based on dependent syntactic trees, which improves the classification performance of the models to some extent. However, the technical limitations of dependent syntactic trees can introduce considerable noise into the model. Meanwhile, it is difficult for a single graph convolutional network to aggregate both semantic and syntactic structural information of nodes, which affects the final sentence classification. To cope with the above problems, this paper proposes a bi-channel graph convolutional network model. The model introduces a phrase structure tree and transforms it into a hierarchical phrase matrix. The adjacency matrix of the dependent syntactic tree and the hierarchical phrase matrix are combined as the initial matrix of the graph convolutional network to enhance the syntactic information. The semantic information feature representations of the sentences are obtained by the graph convolutional network with a multi-head attention mechanism and fused to achieve complementary learning of dual-channel features. Experimental results show that the model performs well and improves the accuracy of sentiment classification on three public benchmark datasets, namely Rest14, Lap14 and Twitter. 展开更多
关键词 Aspect-level Sentiment Analysis Sentiment Knowledge Multi-Head Attention Mechanism Graph Convolutional Networks
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Cumulative effects of excess high-normal alanine aminotransferase levels in relation to new-onset metabolic dysfunction-associated fatty liver disease in China 被引量:7
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作者 Jing-Feng Chen Zhuo-Qing Wu +5 位作者 Hao-Shuang Liu Su Yan You-Xiang Wang Miao Xing Xiao-Qin Song Su-Ying Ding 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1346-1357,共12页
BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations ... BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations between repeated high-normal ALT measurements and the risk of new-onset MAFLD prospectively.METHODS A cohort of 3553 participants followed for four consecutive health examinations over 4 years was selected.The incidence rate,cumulative times,and equally and unequally weighted cumulative effects of excess high-normal ALT levels(ehALT)were measured.Cox proportional hazards regression was used to analyse the association between the cumulative effects of ehALT and the risk of new-onset MAFLD.RESULTS A total of 83.13%of participants with MAFLD had normal ALT levels.The incidence rate of MAFLD showed a linear increasing trend in the cumulative ehALT group.Compared with those in the low-normal ALT group,the multivariate adjusted hazard ratios of the equally and unequally weighted cumulative effects of ehALT were 1.651[95%confidence interval(CI):1.199-2.273]and 1.535(95%CI:1.119-2.106)in the third quartile and 1.616(95%CI:1.162-2.246)and 1.580(95%CI:1.155-2.162)in the fourth quartile,respectively.CONCLUSION Most participants with MAFLD had normal ALT levels.Long-term high-normal ALT levels were associated with a cumulative increased risk of new-onset MAFLD. 展开更多
关键词 Metabolic dysfunction-associated fatty liver disease High-normal alanine aminotransferase level Cumulative effect Cox proportional hazards regression Cohort study
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Dynamic characteristics of coal specimens with varying static preloading levels under low-frequency disturbance load 被引量:1
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作者 WEN Xiao-ze FENG Guo-rui +5 位作者 GUO Jun YU Lu-yang QIAN Rui-peng ZHANG Jie ZHANG Peng-fei FENG Wen-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2644-2657,共14页
The mechanical properties of residual coal pillars under the influence of upward mining disturbances significantly affect the safety of residual mining activities on working faces.This study conducted low-frequency di... The mechanical properties of residual coal pillars under the influence of upward mining disturbances significantly affect the safety of residual mining activities on working faces.This study conducted low-frequency disturbance dynamic uniaxial compression tests on coal specimens using a self-developed dynamic-static load coupling electro-hydraulic servo system,and studied the strength evolutions,surface deformations,acoustic emission(AE)characteristic parameters,and the failure modes of coal specimens with different static preloading levels were studied.The disturbance damage is positively correlated with the coal specimen static preload level.Specifically,the cumulative AE count rates of the initial accelerated damage stage for the coal specimens with static preloading level of 60%and 70%of the uniaxial compressive strength(UCS)were 2.66 and 3.19 times that of the 50%UCS specimens,respectively.Macroscopically,this behaviour manifested as a decrease in the compressive strength,and the mean strengths of the disturbance-damaged coal specimens with 60%and 70%of UCS static preloading decreased by 8.53%and 9.32%,respectively,compared to those of the specimens under pure static loading.The crack sources,such as the primary fissures,strongly control the dynamic response of the coal specimen.The difference between the dynamic responses of the coal specimens and that of dense rocks is significant. 展开更多
关键词 low-frequency disturbance dynamic response coal specimens static preloading level
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Depression and anxiety,peripheral blood inflammatory factors,and stress levels on therapeutic outcomes in patients with chronic wounds 被引量:1
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作者 Bo Li Cha Li +1 位作者 Xian-Jiang Zhong Xiang-Rong Xu 《World Journal of Psychiatry》 SCIE 2024年第12期1836-1844,共9页
BACKGROUND The incidence of chronic wounds is rising due to an aging population and lifestyle changes in our country.In addition,as the disease spectrum evolves,chronic wounds have become common clinical issues that s... BACKGROUND The incidence of chronic wounds is rising due to an aging population and lifestyle changes in our country.In addition,as the disease spectrum evolves,chronic wounds have become common clinical issues that seriously threaten health and impose significant social and economic burdens.AIM To investigate how depression,anxiety,peripheral blood inflammatory factors,and stress levels affect therapeutic outcomes in patients with chronic wounds.METHODS Retrospectively collected clinical data from 110 patients with chronic wounds treated at Changde Hospital,Xiangya School of Medicine,Central South University(The First People’s Hospital of Changde City)between January 2021 and December 2023,categorizing them into effective and ineffective groups based on treatment effects.Differences between both groups were analyzed using univariate analysis,independent risk factors identified via logistic regression,and their predictive value assessed through receiver operating characteristic analysis.RESULTS Following treatment,95 cases were classified as the effective group(cured or improved),while 15 cases with improvement formed the ineffective group.Significant differences between both groups were noted in wound area,infection status,daily bed time,Hamilton Anxiety Rating Scale(HAMA)scores,Hamilton Depression Rating Scale(HAMD)scores,and levels of interleukin-6,tumor necrosis factor-alpha,and superoxide dismutase(P<0.05).Logistic regression analysis identified a wound area≥7 cm^(2),HAMA≥9 scores,and HAMD≥8 scores were independent risk factors for ineffective treatment in patients with chronic wounds(P<0.05).The receiver operating characteristic curve analysis revealed that the area under the curve for ineffective treatment based on wound area,HAMA,and HAMD was 0.767,0.805,and 0.768 respectively.CONCLUSION Wound size,anxiety,and depression are significant factors influencing the therapeutic outcomes in patients with chronic wounds that require careful attention,alongside the development of appropriate strategies. 展开更多
关键词 Chronic wound DEPRESSION ANXIETY Inflammatory factors Stress level Clinical effect
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Is Public Co-Ordination of Investment in Information Security Desirable?
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作者 Christos Ioannidis David Pym Julian Williams 《Journal of Information Security》 2016年第2期60-80,共21页
This paper provides for the presentation, in an integrated manner, of a sequence of results addressing the consequences of the presence of an information steward in an ecosystem under attack and establishes the approp... This paper provides for the presentation, in an integrated manner, of a sequence of results addressing the consequences of the presence of an information steward in an ecosystem under attack and establishes the appropriate defensive investment responses, thus allowing for a cohesive understanding of the nature of the information steward in a variety of attack contexts. We determine the level of investment in information security and attacking intensity when agents react in a non-coordinated manner and compare them to the case of the system’s coordinated response undertaken under the guidance of a steward. We show that only in the most well-designed institutional set-up the presence of the well-informed steward provides for an increase of the system’s resilience to attacks. In the case in which both the information available to the steward and its policy instruments are curtailed, coordinated policy responses yield no additional benefits to individual agents and in some case they actually compared unfavourably to atomistic responses. The system’s sustainability does improve in the presence of a steward, which deters attackers and reduces the numbers and intensity of attacks. In most cases, the resulting investment expenditure undertaken by the agents in the ecosystem exceeds its Pareto efficient magnitude. 展开更多
关键词 Information Security Information Stewardship INVESTMENT Public co-ordination
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Water, Sanitation and Hygiene in Lower-Level Health Care Facilities of Dar es Salaam Region in Tanzania: Status towards Achieving the Sustainable Development Goals and Way Forward
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作者 Mariam Mahamudu Hussein Mohamed +8 位作者 Michael Habtu Dennis Rweyemamu Anyitike Mwakitalima Amour Seleman Erick Mgina Khalid Massa Grace Saguti Andre Arsene Bita Fouda Zabulon Yoti 《Advances in Infectious Diseases》 CAS 2024年第1期279-295,共17页
Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) ... Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) has set a target for each United Nations member state to reach by 2030. Each member state is required to reach by 2022, 2025 and 2030 at least 60%, 80% and 100%, respectively of basic level of service of the five elements which are water, sanitation, hygiene, waste management and environmental cleaning. Methods: This study aimed to evaluate and document the current state of basic water, sanitation, and hygiene services in all lower-level health care facilities in the Dar es Salaam region of Tanzania as of July 2022. A cross-sectional study was conducted in 99 public dispensaries in the Dar es Salaam region’s five councils: Ubungo, Kigamboni, Kinondoni and Temeke Municipalities, and Ilala City. The interviewee form and observational checklists were both digitalized using the Kobo tool software. The respondents were health care facility in-charges or nurse in-charges. Data were downloaded, validated, and imported to Stata version 15 for analysis. Results: The basic WASH level per JMP is far below the target in 2022. Each member state by 2022 is required to reach at least 60% of the basic level of service of each element. We found a low coverage of basic WASH in the 99 dispensaries included in this study. The basic WASH coverage was met in only 10 (10.1%) of the dispensaries, while the remaining 89 (89.9%) dispensaries fall on limited WASH services. Conclusion: This study revealed lower coverage of basic WASH services in dispensaries. An urgent need is required to improve the status of WASH in all the dispensaries and facilitate the provision of quality health care services, patient safety and reduce health care associated infections. 展开更多
关键词 Dispensaries Low level Health Care Facilities Service levels Basic WASH Dar es Salaam
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基于ε-level蝙蝠算法的无人机三维航迹规划 被引量:4
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作者 王福仪 孟秀云 张海阔 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第5期1593-1603,共11页
针对复杂地形环境、存在各种威胁和约束的无人机航迹规划问题,提出了一种基于ε-level改进蝙蝠算法的航迹规划算法。根据无人机目标函数和约束条件,建立无人机三维航迹规划模型;其次,针对蝙蝠算法处理高维带约束问题存在的早熟现象,设... 针对复杂地形环境、存在各种威胁和约束的无人机航迹规划问题,提出了一种基于ε-level改进蝙蝠算法的航迹规划算法。根据无人机目标函数和约束条件,建立无人机三维航迹规划模型;其次,针对蝙蝠算法处理高维带约束问题存在的早熟现象,设计了自适应权重系数和迭代阈值以平衡算法的探索能力和开发能力,并结合ε-level比较策略提高算法对非凸非线性约束优化问题的处理能力;设计了转弯半径可变的Dubins曲线用来对航迹进行平滑处理并解决2个航迹点连线贯穿地形的问题。通过仿真实验,并与蝙蝠算法、粒子群优化算法、ε-level粒子群优化算法和ε-level差分进化算法相比较,所提算法在开发能力、稳定性和成功率等方面都表现出较优的性能。 展开更多
关键词 无人机航迹规划 蝙蝠算法 自适应权重系数 ε-level比较策略 Dubins平滑
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Analysis of level structure and monopole effects in Ca isotopes
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作者 Jin Li Ai-Xi Chen +1 位作者 Amir Jalili Han-Kui Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期161-167,共7页
Understanding the properties of nuclei near the double magic nucleus^(40)Ca is crucial for both nuclear theory and experiments.In this study,Ca isotopes were investigated using an extended pairing-plus-quadrupole mode... Understanding the properties of nuclei near the double magic nucleus^(40)Ca is crucial for both nuclear theory and experiments.In this study,Ca isotopes were investigated using an extended pairing-plus-quadrupole model with monopole corrections.The negative-parity states of^(44)Ca were coupled with the intruder orbital g_(9/2)at 4 MeV.The values of E_(4+)/E_(2+)agree well with experimental trend from^(42)Ca to^(50)Ca,considering monopole effects between νf_(7/2)and νp_(3/2)(νf_(5/2)).This monopole effect,determined from data of^(48)Ca and^(50)Ca,supports the proposed new nuclear magic number N=34 by predicting a high-energy 2^(+)state in^(54)Ca. 展开更多
关键词 Shell model Doubly magic ISOTOPES Monopole effects level structure
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Dynamics of information diffusion and disease transmission in time-varying multiplex networks with asymmetric activity levels
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作者 谢笑笑 霍良安 +1 位作者 董雅芳 程英英 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期690-699,共10页
While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network evolution.In this study,we construct a new two-layer ... While the interaction between information and disease in static networks has been extensively investigated,many studies have ignored the characteristics of network evolution.In this study,we construct a new two-layer coupling model to explore the interactions between information and disease.The upper layer describes the diffusion of disease-related information,and the lower layer represents the disease transmission.We then use power-law distributions to examine the influence of asymmetric activity levels on dynamic propagation,revealing a mapping relationship characterizing the interconnected propagation of information and diseases among partial nodes within the network.Subsequently,we derive the disease outbreak threshold by using the microscopic Markov-chain approach(MMCA).Finally,we perform extensive Monte Carlo(MC)numerical simulations to verify the accuracy of our theoretical results.Our findings indicate that the activity levels of individuals in the disease transmission layer have a more significant influence on disease transmission compared with the individual activity levels in the information diffusion layer.Moreover,reducing the damping factor can delay disease outbreaks and suppress disease transmission,while improving individual quarantine measures can contribute positively to disease control.This study provides valuable insights into policymakers for developing outbreak prevention and control strategies. 展开更多
关键词 information diffusion disease transmission asymmetric activity levels quarantine strength
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Monitoring absolute vertical land motions and absolute sea-level changes from GPS and tide gauges data over French Polynesia
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作者 Xianjie Li Jean-Pierre Barriot +2 位作者 Bernard Ducarme Marania Hopuare Yidong Lou 《Geodesy and Geodynamics》 EI CSCD 2024年第1期13-26,共14页
In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as an... In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as ancillary results,estimates of the absolute changes in sea level at the same locations.To verify our processing approach to determining vertical motion,we first modeled vertical motion at the International GNSS Service(IGS)THTI station located in the capital island of Tahiti and compared our estimate with previous independent determinations,with a good agreement.We obtained the following estimates for the vertical land motions at the tide gauges:Tubuai island,Austral Archipelago-0.92±0.17 mm/yr,Vairao village,Tahiti Iti:-0.49±0.39 mm/yr,Rikitea,Gambier Archipelago-0.43±0.17 mm/yr.The absolute variations of the sea level are:Tubuai island,Austral Archipelago 5.25±0.60 mm/yr,Vairao village,Tahiti Iti:3.62±0.52 mm/yr,Rikitea,Gambier Archipelago 1.52±0.23 mm/yr.We discuss these absolute values in light of the values obtained from altimetric measurements and other means in French Polynesia. 展开更多
关键词 GPS Tide gauges Sea level changes Vertical land motion
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Source and level of dietary iron influence semen quality by affecting inflammation, oxidative stress and iron utilization levels in boars
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作者 Yinghui Wu Yamei Li +8 位作者 Yueyue Miao Hongkui Wei Hefeng Luo Chunxiao Ren Yawei Zhang Juan Chen Tanghong Wei Jiyan Deng Jian Peng 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期2044-2058,共15页
Background Boars fed a mixed form of inorganic and organic iron in excess of the NRC recommended levels still develop anemia,which suggested that the current level and form of iron supplementation in boar diets may be... Background Boars fed a mixed form of inorganic and organic iron in excess of the NRC recommended levels still develop anemia,which suggested that the current level and form of iron supplementation in boar diets may be inappropriate.Therefore,56 healthy Topeka E line boars aged 15–21 months were randomly divided into 5 groups:basal diet supplemented with 96 mg/kg ferrous sulfate(FeSO_(4))and 54 mg/kg glycine chelated iron(Gly-Fe,control);80 mg/kg or 115 mg/kg Gly-Fe;80 mg/kg or 115 mg/kg methionine hydroxyl analogue chelated iron(MHA-Fe,from CalimetFe)for 16 weeks.The effects of dietary iron supplementation with different sources and levels on semen quality in boars were investigated.Results 1)Serum Fe and hemoglobin concentrations were not affected by reduced dietary iron levels in the 80 mg/kg or 115 mg/kg Gly-Fe and MHA-Fe groups compared with the control group(P>0.05).2)Serum interleukin-6(IL-6)and sperm malondialdehyde(MDA)levels in the 80 mg/kg or 115 mg/kg MHA-Fe groups were lower than those in the control group(P<0.05),and higher serum superoxide dismutase levels and lower MDA levels in the 115 mg/kg MHA-Fe group(P<0.05).3)Boars in the 80 mg/kg or 115 mg/kg Gly-Fe and MHA-Fe groups had lower serum hepcidin(P<0.01),ferritin(P<0.05),and transferrin receptor(P<0.01)concentrations,and boars in the 115 mg/kg MHA-Fe group had higher seminal plasma Fe concentrations compared with the control group.4)Boars in the 80 mg/kg and 115 mg/kg MHA-Fe groups had lower abnormal sperm rate and in situ oscillating sperm ratio compared to the control group at weeks 12 and/or 16 of the trial.However,the effect of Gly-Fe on improving semen quality in boars was not evident.5)Serum IL-6 level was positively correlated with hepcidin concentration(P<0.05),which in turn was significantly positively correlated with abnormal sperm rate(P<0.05).Furthermore,significant correlations were also found between indicators of iron status and oxidative stress and semen quality parameters.Conclusions Dietary supplementation with 80 mg/kg or 115 mg/kg MHA-Fe did not induce iron deficiency,but rather reduced serum inflammatory levels and hepcidin concentration,alleviated oxidative stress,increased body iron utilization,and improved semen quality in adult boars. 展开更多
关键词 Adult boars Iron level Iron source Iron status Semen quality
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Methodology for local correction of the heights of global geoid models to improve the accuracy of GNSS leveling
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作者 Stepan Savchuk Alina Fedorchuk 《Geodesy and Geodynamics》 EI CSCD 2024年第1期42-49,共8页
At present,one of the methods used to determine the height of points on the Earth’s surface is Global Navigation Satellite System(GNSS)leveling.It is possible to determine the orthometric or normal height by this met... At present,one of the methods used to determine the height of points on the Earth’s surface is Global Navigation Satellite System(GNSS)leveling.It is possible to determine the orthometric or normal height by this method only if there is a geoid or quasi-geoid height model available.This paper proposes the methodology for local correction of the heights of high-order global geoid models such as EGM08,EIGEN-6C4,GECO,and XGM2019e_2159.This methodology was tested in different areas of the research field,covering various relief forms.The dependence of the change in corrected height accuracy on the input data was analyzed,and the correction was also conducted for model heights in three tidal systems:"tide free","mean tide",and"zero tide".The results show that the heights of EIGEN-6C4 model can be corrected with an accuracy of up to 1 cm for flat and foothill terrains with the dimensionality of 1°×1°,2°×2°,and 3°×3°.The EGM08 model presents an almost identical result.The EIGEN-6C4 model is best suited for mountainous relief and provides an accuracy of 1.5 cm on the 1°×1°area.The height correction accuracy of GECO and XGM2019e_2159 models is slightly poor,which has fuzziness in terms of numerical fluctuation. 展开更多
关键词 GNSS leveling Global geoid model Gravity anomaly Weight data Correcting data
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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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