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Strategies of allocating root-shoot biomass in plantations and natural forests at various community stages and moisture levels
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作者 Wenjing Chen Lei Liu +3 位作者 Josep Penuelas Guoyi Zhou Langqin Hua Zhurong Wu 《Journal of Forestry Research》 2026年第2期85-99,共15页
The root-to-shoot(R/S)ratio is a critical indicator of the balance between root biomass and shoot biomass,representing the ecological strategies and adaptive responses of plants to environmental conditions.However,the... The root-to-shoot(R/S)ratio is a critical indicator of the balance between root biomass and shoot biomass,representing the ecological strategies and adaptive responses of plants to environmental conditions.However,the patterns of change in community R/S ratios during forest succession and their response to moisture levels across broad geographic gradients remains unclear.Based on forest biomass data from a national field inventory of 5,825 plots conducted across China between 2011 and 2015,this study looked into allocating biomass shoots and roots at the early,middle,and late stages of growth in plantations and succession in natural forests,and evaluated how moisture availability influences this allocation.The results revealed a significant decline in R/S ratios from early to late stages for both plantations and natural forests.Shoot and root biomass in plantations grew isometrically during the early and middle succession stages but shifted to allometric growth in the late stage,with the slope of the log-transformed shoot-root biomass relationship differing significantly across growth stages.Natural forests,in contrast,maintained isometric growth across successional stages,showing no significant variation in the slope of the log-transformed shoot-root biomass relationship.Environmental factors,particularly moisture levels,strongly influenced R/S ratios.Moisture levels significantly affected size-corrected R/S ratios,particularly in the middle stage of plantations and the early and middle stages of natural forests,supporting the hypothesis of optimal allocation.These findings suggest that in water-limited regions,forest management should prioritize drought-tolerant,deep-rooted native species,encourage mixed-species planting in the early stage,and reduce logging intensity in mature plantations.Conserving natural forests to maintain successional dynamics is essential for long-term ecological resilience.These findings emphasize the importance of balancing productivity with ecological sustainability by adapting practices to specific environments and forest types under climate change. 展开更多
关键词 Root-to-shoot ratios Biomass allocation Forest type Community stage Moisture levels Allometric scaling
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The characteristics of cerebral cortical oxygenation levels and functional connectivity under upper and lower limb exercise-induced fatigue
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作者 Feng Li Yajie Wang +3 位作者 Xinyi Wang Jiawei Bi Ye Luo Lingyan Huang 《Sports Medicine and Health Science》 2026年第1期61-69,共9页
This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fati... This study aims to explore the impact of fatigue induced by different limb exercises on cerebral cortical oxygenation levels and functional connectivity strength using functional near-infrared spectroscopy(fNIRS).Fatigue was induced using an upper limb ergometer or a lower limb ergometer,with the load increasing gradually each minute.fNIRS covering the prefrontal cortex and motor cortex were used to collect data during the resting state,both before and after fatigue induction.A two-way ANOVA was conducted to examine differences in oxyhemoglobin(HbO_(2))and functional connectivity before and after fatigue induction in both groups,with the significance level set at 0.05.Exercise-induced fatigue in both the upper and lower limbs leads to a significant decrease in cerebral cortical oxygenation levels.Upper limb fatigue leads to a significant reduction in functional connectivity,there were significant decreases in connectivity within the motor cortex,between the motor cortex and frontal regions,and between the right ventrolateral prefrontal cortex and other frontal regions.Conversely,no significant changes were observed before and after lower limb fatigue.Future studies should focus on examining the extent to which how changes in the cerebral cortex,induced by exercise fatigue,are linked to exercise-and/or performance-related outcomes. 展开更多
关键词 Brain functional connectivity Cerebral oxygenation level Exercise-induced fatigue Functional near-infrared spectroscopy
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Simulating Groundwater Levels Responses to Precipitation and Withdrawal:A Lag-time Deep Learning Model
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作者 LI Shuai ZHU Lin +3 位作者 GAO Lei GONG Huili LI Xiaojuan SU Xiaosi 《Chinese Geographical Science》 2026年第2期351-364,共14页
Groundwater level(GWL)is a key indicator used to accurately assess groundwater resources and form the foundation for ef-fective groundwater management.This paper integrates a Gate Recurrent Unit(GRU)model with a Multi... Groundwater level(GWL)is a key indicator used to accurately assess groundwater resources and form the foundation for ef-fective groundwater management.This paper integrates a Gate Recurrent Unit(GRU)model with a Multi-head Self-attention mechan-ism(MSAM-GRU)to simulate GWLs in both confined and unconfined aquifers simultaneously.The model innovatively captures the lag times between GWLs in the unconfined aquifer and precipitation,as well as between GWLs in the confined aquifer and the upper aquifer.We have assessed the effectiveness of the proposed model using a case study in the Beijing Plain,China from January 2005 to December 2020.With the consideration of lag times,the results indicated that the MSAM-GRU model exhibits a maximum 67%and 73%reduction in RMSE compared to the Attention mechanism-GRU(AM-GRU)and GRU model,respectively.MSAM-GRU model exhibited a 31%reduction in RMSE and a 0.12 increase in R^(2) compared to the same model that do not account for lag time.In Region I,the shortest lag time of GWL in the unconfined aquifer was two months,while that in the confined aquifer was three months,indicating a longer delayed response in the confined aquifer.MSAM-GRU model considering lag time,was then applied to simulate the GWLs in the unconfined aquifer under different scenarios and to analyze whether GWL fluctuations affect subway operations.The simulation res-ults showed that under the scenario 1,the GWL in the unconfined aquifer would rise above the depth of subway station floor,threaten-ing the operation of subways.This study can provide reliable technical support for the accurate simulation of GWLs in multi-aquifer systems. 展开更多
关键词 groundwater level(GWL) Multi-head Self-attentionmechanism-Gate Recurrent Unit(MSAM-GRU) PRECIPITATION unconfined aquifer and confined aquifer Beijing Plain China
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Mineralization at Different Structural Levels in the Crust 被引量:1
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作者 LI Saisai ZHANG Hongrui HOU Zengqian 《Acta Geologica Sinica(English Edition)》 2025年第4期1042-1058,共17页
Metallogenic research on structural levels can reveal vertical patterns of mineralization and facilitate the deep exploration of economic minerals.However,research focusing on the correlation between structural levels... Metallogenic research on structural levels can reveal vertical patterns of mineralization and facilitate the deep exploration of economic minerals.However,research focusing on the correlation between structural levels and mineralization remains limited.In this study,we summarize the deformation patterns and associated mineral deposits observed at different crustal levels(i.e.,surface,shallow,middle,and deep structural levels,corresponding to depths of<2,2-8,8-15,and>15 km,respectively).Furthermore,we examine the genetic association between structural levels and metallogenesis,demonstrating that distinct structural levels are linked to specific types of mineralization.Key factors that vary across crustal levels include temperature,pressure,and fluid circulation.Ore-forming processes involve interactions between structures and fluids under varying temperatures and pressures.Structural levels influence mineralization by controlling the temperatures,pressures,and deformation mechanisms that drive the activation,migration,and enrichment of ore-forming materials. 展开更多
关键词 deformation MINERALIZATION structural control structural level crustal level
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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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Effect of minimum and maximum electrical stimulation levels on sound field thresholds,and speech perception in children using the Advanced Bionics Cochlear Implant
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作者 Muthuselvi Thangaraj Ravikumar Arunachalam +1 位作者 Madhuri Gore Ajith Kumar Uppunda 《Journal of Otology》 2025年第3期170-175,共6页
BackgroundIt's crucial to study the effect of changes in thresholds(T)and most comfortable levels(M)on behavioral measurements in young children using cochlear implants.This would help the clinician with the optim... BackgroundIt's crucial to study the effect of changes in thresholds(T)and most comfortable levels(M)on behavioral measurements in young children using cochlear implants.This would help the clinician with the optimization and validation of programming parameters.ObjectiveThe study has attempted to describe the changes in behavioral responses with modification of T and M levels.MethodsTwenty-five participants in the age range 5 to 12 years using HR90K/HiFocus1J or HR90KAdvantage/HiFocus1J with Harmony speech processors participated in the study.A decrease in T levels,a rise in T levels,or a decrease in M levels in the everyday program were used to create experimental programs.Sound field thresholds and speech perception were measured at 50 dBHL for three experimental and everyday programs.ConclusionThe results indicated that only reductions of M levels resulted in significantly(p<0.01)poor aided thresholds and speech perception.On the other hand,variation in T levels did not have significant changes in either sound field thresholds or speech perception.The results highlight that M levels must be correctly established in order to prevent decreased speech perception and audibility. 展开更多
关键词 T levels M levels sound field threshold speech perception
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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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Effectiveness of the combination of Fe tablets and beetroot juice in increasing Hb levels of pregnant women with anemia
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作者 Aulia Amini Baiq Nurbaety 《Frontiers of Nursing》 2025年第4期423-431,共9页
Objective:This study aims to determine the effectiveness of giving a combination of Fe tablets and beetroot juice in increasing hemoglobin(Hb)levels of pregnant women with anemia in the Mataram City area.Methods:This ... Objective:This study aims to determine the effectiveness of giving a combination of Fe tablets and beetroot juice in increasing hemoglobin(Hb)levels of pregnant women with anemia in the Mataram City area.Methods:This study was designed with quasi-experimental design with pre-test and post-test with control design.The location of this study was conducted in the city of Mataram on pregnant women with anemia.The sample of this study was pregnant women with mild anemia based on inclusion and exclusion criteria,divided into 2 groups:a control group and a treatment group of 15 respondents each,bringing the total respondents to 30 people.Analysis of Hb level measurement results was carried out using the independent sample t-test.Results:The results obtained in the treatment group(combination of beet juice and Fe tablets)were the mean pre-test of 9.93 mg/dL and post-test of 11.90 mg/dL(P-value=0.000),which means there is effectiveness in increasing hemoglobin levels while in the control group.Comparison of increased Hb levels of the control group and significantly different treatments marked by a P value of 0.001.Conclusions:the combination of Fe tablets and beetroot juice is effective in increasing Hb levels of pregnant women with anemia in the Mataram City area. 展开更多
关键词 ANEMIA beet juice EFFECTIVENESS Hb levels pregnant women
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S-scheme heterojunction with intraband defect levels for artificial photosynthesis
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作者 Xiaoming Liu Zhifeng Jiang 《Chinese Journal of Catalysis》 2025年第3期5-7,共3页
The increasing dependence on fossil fuels and the consequent CO_(2)emissions have prompted urgent energy and environmental challenges[1,2].Solar-driven CO_(2)conversion into value-added fuels offers a sustainable and ... The increasing dependence on fossil fuels and the consequent CO_(2)emissions have prompted urgent energy and environmental challenges[1,2].Solar-driven CO_(2)conversion into value-added fuels offers a sustainable and promising solution to these issues[3].However,the practical implementation of CO_(2)photoreduction is constrained by low efficiency,primarily due to the rapid recombination of photogenerated electron-hole pairs[4]. 展开更多
关键词 artificial photosynthesis fossil fuels intraband defect levels HETEROJUNCTION
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Relationships between income levels,lifestyles,occupational factors,and male fertility in peninsular Malaysia
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作者 Nur Fatma Hasni Majid Suriyani Muhamad +3 位作者 Suhal Kusairi Mohd Nasir Nawawi Noor Salihah Zakaria Roszaman Ramli 《Asian pacific Journal of Reproduction》 2025年第2期69-76,共8页
Objective:To explore the associations between income levels,employment risk,lifestyles,occupational stress,and male fertility.Methods:This cross-sectional study analyzed 294 men seeking fertility treatment at fertilit... Objective:To explore the associations between income levels,employment risk,lifestyles,occupational stress,and male fertility.Methods:This cross-sectional study analyzed 294 men seeking fertility treatment at fertility clinics in Terengganu,Pahang,and Kuala Lumpur from November 2021 to June 2023.Data were collected through structured questionnaires covering income levels,lifestyles,employment risks,occupational stress,and semen quality.Multinomial logistic regression was employed to assess predictors of semen quality,with crude and adjusted odds ratios(OR)reported.Results:The lower-income group exhibited higher odds of having abnormal semen quality compared to normal semen quality.Specifically,these participants were more likely to experience azoospermia[crude OR 6.68,95%confidence interval(CI)1.84-52.63;adjusted OR 6.26,95%CI 1.76-51.38],indicating a link between low income and infertility issues.Lifestyle factors did not show significant associations with semen abnormalities after adjustment.High employment risks had significant associations with oligozoospermia after adjustment(crude OR 5.50,95%CI 2.14-14.11;adjusted OR 5.15,95%CI 1.93-13.71),while high occupational stress was linked to asthenozoospermia(crude OR 2.26,95%CI 1.09-4.68;adjusted OR 2.25,95%CI 1.07-4.69).Conclusions:The findings underscore the influence of socioeconomic and occupational factors on male fertility,showing associations between lower income levels,high-risk occupations,and semen abnormalities.In contrast,lifestyle factors did not show significant associations with semen abnormalities after adjustment.Nevertheless,the current findings should be further confirmed through more extensive studies focusing on abnormal semen and lifestyle factors. 展开更多
关键词 Male infertility Income levels Employment risks Occupational stress Lifestyles
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Correlation of Serum 25-hydroxyvitamin D Levels with Senile Hypertension and Its Stroke
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作者 Shasha Zang Qing Zhao +1 位作者 Sha Liu Zhe Li 《Journal of Clinical and Nursing Research》 2025年第4期9-14,共6页
Objective:Correlation of serum 25-hydroxyvitamin D level with senile hypertension and its stroke.Methods:Two hundred hypertensive patients admitted to the hospital from February 2022 to December 2023 were classified a... Objective:Correlation of serum 25-hydroxyvitamin D level with senile hypertension and its stroke.Methods:Two hundred hypertensive patients admitted to the hospital from February 2022 to December 2023 were classified as study subjects.They were divided into grade 2 hypertension group and grade 3 hypertension group,and 100 healthy medical checkups admitted during the same period were analyzed as study subjects.Results:Comparison of diagnostic results between grade 2 hypertension and grade 2 hypertensive stroke patients,there was a difference in 25(OH)D,(P<0.05).Comparison of test results between grade 3 hypertension and grade 3 hypertensive stroke patients,there was a difference in age,BMI,25(OH)D,GLU,LDL-C,(P<0.05).Serum 25-hydroxyvitamin D level is a high-risk factor for the occurrence of stroke in elderly hypertensive patients,so the probability of risk is higher,where 25(OH)D(ng/mL),GLU(mmol/L),there is a difference,(P<0.05).Conclusion:There is a greater relationship between the occurrence of stroke and serum 25-hydroxyvitamin D level in elderly hypertensive patients.The occurrence of the disease has a greater relationship with this indicator in patients and is also a high-risk factor that affects the patients’morbidity,so it is necessary to pay attention to the monitoring of this indicator after the onset of the disease in patients. 展开更多
关键词 Serum 25-hydroxyvitamin D level Geriatric hypertension STROKE CORRELATION
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Assessing the impact of upstream water quality levels on downstream economic growth in China:A high-resolution panel study
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作者 DING Yu WANG Chenglong +3 位作者 SHUAI Chenyang CHEN Xi SUN Jingran ZHAO Bu 《Journal of Geographical Sciences》 2025年第12期2647-2663,共17页
In light of growing challenges posed by water pollution,understanding the multifaceted impacts of water quality on economic performance is an imperative for formulating effective policies aimed at sustainable developm... In light of growing challenges posed by water pollution,understanding the multifaceted impacts of water quality on economic performance is an imperative for formulating effective policies aimed at sustainable development.Existing studies tend to be constrained by limited local data,and lack a perspective on spatial dynamics and regional variations in water quality effects.This study addresses these gaps by examining the influence of upstream water quality on downstream economic growth in China,utilizing high-resolution panel data.Findings reveal that a 1%increase in upstream biochemical oxygen demand(BOD)concentration reduces downstream economic growth by 0.25% nationally.Regionally,the constraining effect varies significantly,ranging from 0.38% in Southwest China(β=-0.38)to 0.92% in North China(β=-0.92).Notably,even in regions with non-polluted water,upstream water quality deterioration continues to impede downstream economic growth.These findings underscore the critical need to integrate water quality considerations into economic policy frameworks and highlight the importance of coordinated,cross-regional water quality management strategies to foster sustainable economic development. 展开更多
关键词 water quality economic growth spatial dynamics water quality levels
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An Empirical Study of the Impact of Digital Literacy and its Mechanisms of Influence on the Levels of Depressive Symptoms of Older Adults
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作者 Li Qiang Li Cong 《Contemporary Social Sciences》 2025年第3期96-113,共18页
This study examines the impact of digital literacy on the levels of depressive symptoms of older adults,utilizing data from the 2022 China Family Panel Studies(CFPS).Factor analysis was used to construct digital liter... This study examines the impact of digital literacy on the levels of depressive symptoms of older adults,utilizing data from the 2022 China Family Panel Studies(CFPS).Factor analysis was used to construct digital literacy indicators,and OLS multiple linear regression modeling was carried out;the results demonstrate that digital literacy exerts a significant negative influence on depressive symptoms in older adults(β=-0.5385,p<0.01),and the findings are robust.Mechanism analysis reveals that digital literacy reduces depressive symptoms by enhancing future confidence(the mediation effect accounts for 18.0%).Heterogeneity analysis also indicates that there are more pronounced depressive symptoms-alleviating effects among male,married,and younger-old adults(aged 60-79)(p<0.01).Policy recommendations include implementing tiered digital literacy education programs with targeted support for vulnerable groups,enriching digital education resources through dedicated digital service platforms for the elderly,and strengthening psychological interventions to boost future confidence for effective depressive symptoms mitigation. 展开更多
关键词 digital literacy level of depressive symptoms older adults factor analysis
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Analysis of Community Elderly Care Facility Demand Levels and Functional Grouping Insights: A Case Study of Xueyuan Road Street in Haidian District, Beijing
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作者 GUO Yuhan CAO Ying 《Journal of Landscape Research》 2025年第3期27-32,共6页
This study focuses on the elderly population in Xueyuan Road Street of Haidian District in Beijing.Through KANO questionnaires and the theory of attractive quality,it investigates the demand levels and degrees for dif... This study focuses on the elderly population in Xueyuan Road Street of Haidian District in Beijing.Through KANO questionnaires and the theory of attractive quality,it investigates the demand levels and degrees for different community elderly care services.It introduces the Anderson behavioral model to analyze the influencing factors,categorizes different demographics,and examines the needs of elderly individuals with varying characteristics,proposing suggestions for the improvement of future community elderly care service facilities. 展开更多
关键词 Community elderly care Demand levels KANO model Anderson behavioral model
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Abnormal salinity levels increase shrimp Penaeus monodon disease risk:insights from the disrupted gut microbiota
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作者 Yufeng WANG Yangming LU +1 位作者 Qiongfen QIU Jinbo XIONG 《Journal of Oceanology and Limnology》 2025年第6期2002-2018,共17页
Owing to the extreme rainfall and evaporation events under the changing climate,coastal zones are experiencing salinity fluctuations that stress aquatic organisms.However,the biological consequences of ongoing alterat... Owing to the extreme rainfall and evaporation events under the changing climate,coastal zones are experiencing salinity fluctuations that stress aquatic organisms.However,the biological consequences of ongoing alteration in salinity levels on euryhaline organisms remain inconclusive.Herein,we sought to uncover how variation in salinity level adversely alters the bacterioplankton community,the gut microbiota of euryhaline shrimp Penaeus monodon,and subsequent shrimp disease risk.To mimic the extreme weather that induces abrupt changes in coastal water salinity,three salinity levels(10,20,and 30)were selected to investigate the differences in shrimp gut microbiota using bacterial 16S rRNA gene sequencing.Results shows that salinity level and days post experiment(dpe)respectively constrained 45.9%and 13.0%of the variance in the gut bacterial communities.Particularly,abnormal salinity levels accelerated temporal turnover rate,disrupted gut network stability,augmented average variation degree,and increased pathogenic potential in the gut microbiota of shrimp reared at 10 and 30 salinities compared with 20 salinity controls.These changes were accompanied with the shifts in the gut microbiota-mediated functions,especially the compromised immunity and elevated infectious diseases potentials,thereby increasing shrimp disease risk.In addition,abnormal salinity levels increased the role of homogeneous selection governing the gut microbiota.After excluding the dpe-effect,we screened 35 gut salinity-discriminatory taxa that quantitatively discriminated the salinity levels where shrimp were reared,with overall accuracy of 91.1%.Collectively,abnormal salinity levels profoundly disrupt the structure,stability,assembly,and functions of the gut microbiota,which in turn increased disease risk in shrimp.In addition,gut symbionts sensitively responded to the changes in external salinity level.These findings deepened our understanding on the biological consequence of abnormal salinity levels on shrimp health. 展开更多
关键词 Penaeus monodon abnormal salinity level gut microbiota ecological process disease risk
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Knowledge Level and Self-Reported Attitudes of Food Handlers: Case Study of a University Campus
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作者 Kamila Soares Irene Oliveira +2 位作者 Alexandra Esteves Maria C. Fontes Cristina Saraiva 《Health》 CAS 2016年第13期1383-1396,共14页
This study was performed conducting surveys to assess the Knowledge Level (KL) and Self-Reported Attitudes (SRA) of Food Handlers (FH) in order to evaluate their food safety perception. Food handlers working in 5 cafe... This study was performed conducting surveys to assess the Knowledge Level (KL) and Self-Reported Attitudes (SRA) of Food Handlers (FH) in order to evaluate their food safety perception. Food handlers working in 5 cafes and 6 canteens in a university campus responded to a questionnaire about food hygiene. The knowledge level about food hygiene was obtained by answering five question groups (G): Agents involved in food borne diseases (G1), Food handling hygiene (G2), Cross contamination (G3), Heat treatment/cooling techniques (G4), Reduced temperatures (G5). The SRA level was obtained through seven questions with multiple choice options on behaviors of health and safety applied to the work routine, which were considered as percentage of hits. The hygiene’s knowledge average was 75%, ranging from 63.3% (G4) to 94.5% (G3). Significant associations between establishment type and G1 (p = 0.027), professional experience and G5 (p = 0.020), training and G5 (p = 0.037) were found. Food handlers knowledge did not have effect in FH attitude (p = 0.371). From 25 FH (46.0%) who had high KL, 17 had reported incorrect attitudes. The level of hits is, in general, more than 75%, except for matters relating to the use of different cutting tables (44.4%) and knives (51.9%). Significant differences of values and odds for handlers’ knowledge were observed between cafes’ and canteens’ FH. No difference (p > 0.05) was observed in FH SRA scores according to the type of establishment. The results reveal a reduced application of knowledge acquired by food handlers, evidenced by the low level of attitudes considered correct. This clearly justifies the implementation of additional measures, including on job training as part of an effective strategy to control establishment’s food safety. 展开更多
关键词 Food Handlers KNOWLEDGE self-reported Attitudes TRAINING Food Safety
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Determination of Trophic Levels of Marine Fish Using Stable Isotope Analysis of Fish Scale Nitrogen(δ15N)in the Yellow Sea and Northern East China Sea
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作者 BAI Huaiyu HUANG Lingfeng SUN Yao 《Journal of Ocean University of China》 2025年第3期735-744,共10页
Fish scaleδ^(15)N(δ^(15)N_(sca))records trophic information of the whole life history for marine fishes.Data from gut content and values calculated from white muscle tissue(WMT)are insufficient for assessing trophic... Fish scaleδ^(15)N(δ^(15)N_(sca))records trophic information of the whole life history for marine fishes.Data from gut content and values calculated from white muscle tissue(WMT)are insufficient for assessing trophic level(TL)of marine fishes as they only provide the information of several months or even several days.Stable isotope analysis(SIA)of nitrogen was carried out in fish scales and WMT of 16 species from a total of 28 individuals captured from the Yellow Sea and northern East China Sea in October and November of 2019,aiming at discovering the correlation betweenδ^(15)N_(sca) and fish WMTδ^(15)N(δ^(15)NWMT),so as to useδ^(15)N_(sca) for the characterization of TLs of marine fish.Scales were analyzed without prior carbonate dissolution as a pre-processing step.TL calculated fromδ^(15)N_(sca) was compared to traditional TL formula calculated withδ^(15)N_(WMT) to estimate the accuracy.We found that there was a highly significant and positive correlation(r=0.830,P<0.001)betweenδ^(15)N_(sca) andδ^(15)N_(WMT).TL calculation results using fish scale(TL_(sca))and WMT(TL_(WMT))showed congruence(r=0.773,P<0.001),and the regression coefficient betweenδ^(15)N_(sca) andδ^(15)NWMT was used for calculating TLsca.The conversion was conducted for the purpose of comparison with previousδ^(15)N_(WMT)-based calculation results of TL.TLsca calculation results were 81.25%within the TL range of±10%calculated withδ^(15)NWMT.The findings in the present study showed thatδ^(15)N_(sca) is a viable technique for the characterization of the TL of marine fish and can help to predict food web and support the study of marine ecosystem. 展开更多
关键词 fish scale stable isotope analysis trophic level Yellow Sea northern East China Sea
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Plasma extracellular cold inducible RNA-binding protein levels are elevated for 1 month post-colectomy which may promote metastases
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作者 H M C Shantha Kumara Poppy Addison +7 位作者 Xiao-Hong Yan Anuj Raj Sharma Neil Mitra Hansani N Angammana Yanni Hedjar Yi-Ru Chen Vesna Cekic Whelan L Richard 《World Journal of Gastrointestinal Oncology》 2025年第4期318-326,共9页
BACKGROUND Cold-inducible RNA-binding protein(CIRP)is related to a family of stressinduced RNA-binding proteins.It is primarily found in the nucleus,where it regulates transcription.Under stress,CIRP translocates to t... BACKGROUND Cold-inducible RNA-binding protein(CIRP)is related to a family of stressinduced RNA-binding proteins.It is primarily found in the nucleus,where it regulates transcription.Under stress,CIRP translocates to the cytoplasm where it modulates translation;a subset is secreted as extracellular CIRP(eCIRP)which is a damage-associated molecular pattern(DAMP)molecule that stimulates the production of inflammatory mediators.Elevated blood eCIRP levels may foster immune tolerance and facilitate tumor growth.Increased CIRP levels have been noted in various malignancies including colorectal cancer(CRC).This study’s objective was to determine plasma eCIRP levels before and after minimally invasive colorectal resection(MICR)for CRC.AIM To assess plasma eCIRP levels prior to and following minimally invasive colorectal resection in the context of cancer pathology.METHODS MICR patients from an IRB-approved data/tissue bank for whom plasma samples were available were eligible.Plasma specimens were obtained preoperatively(preop)and at least 3 time’s postop[between postoperative day(POD)1-41];late samples were grouped into 7-day blocks and were considered separate time points.eCIRP levels were assessed via enzyme-linked immunosorbent assay(pg/mL)and results presented as mean±SD,analysis with Wilcoxon paired t-test.RESULTS A total of 83 CRC patients who underwent MICR[colon 66%,rectal 34%;laparoscopic-assisted(LA),70%;handassisted laparoscopic(HAL),30%]were studied.The mean preop eCIRP level was 896.8±757.0 pg/mL.Elevations in mean plasma levels(P=<0.001)were noted on POD1(2549±2632 pg/mL,n=83),POD3(1871±1362 pg/mL,n=77),POD7-13(1788±1403 pg/mL,n=57),POD14-20(1473±738.8 pg/mL,n=30),and POD21-27(1681±1375 pg/mL,n=21).No significant differences were noted at POD 28-41.Higher values were noted in the HAL’s(vs LA)group,however,there were more rectal cancers in the former.CONCLUSION Elevated plasma eCIRP levels persist for a month post MICR for CRC(change from baseline,77%-184%);highest values seen on POD1.The initial surge may be due to the acute inflammatory response while later elevations may be related to wound healing and remodeling.The higher levels noted in the HAL’s group(with greater IL and more rectal cases)suggest the extent of surgical trauma impacts eCIRP levels.Further investigations are needed. 展开更多
关键词 Effects of surgery Plasma extracellular cold-inducible RNA-binding protein levels Colorectal resection Colorectal cancer Angiogenesis
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Modified triphenylamine donors with shallower HOMO energy levels to construct long-wavelength TADF emitters of efficient organic light-emitting diodes
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作者 Hao Zhuo Ming Zhang +5 位作者 Hengyuan Zhang Hui Lin Gang Yang Silu Tao Caijun Zheng Xiaohong Zhang 《Chinese Chemical Letters》 2025年第5期330-335,共6页
Triphenylamine(TPA)is the most promising donor fragment for the construction of long-wavelength thermally activated delayed fluorescence(TADF)emitters owing to its suitable dihedral angle that could enhance radiative ... Triphenylamine(TPA)is the most promising donor fragment for the construction of long-wavelength thermally activated delayed fluorescence(TADF)emitters owing to its suitable dihedral angle that could enhance radiative decay to compete with the serious non-radiative decay.However,the moderate electron-donating capacity of TPA seriously limits the selection of acceptor for constructing longwavelength TADF emitters with narrow bandgaps.To address this issue,in this work,the peripheral benzene of TPA was replaced with 1,4-benzodioxane and anisole to obtain two new electrondonating units N-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)-N-phenyl-2,3-dihydrobenzo[b][1,4]dioxin-6-amine(TPADBO,−5.02 eV)and 4-methoxy-N-(4-methoxyphenyl)-N-phenylaniline(TPAMO,−5.00 eV),which possess much shallower highest occupied molecule orbital(HOMO)energy levels than the prototype TPA(−5.33 eV).Based on TPA and the modified TPA donor fragments,three TADF emitters were designed and synthesized,namely Py-TPA,Py-TPADBO and Py-TPAMO,with the same acceptor fragment 12-(2,6-diisopropylphenyl)pyrido[2′,3′:5,6]pyrazino[2,3-f][1,10]phenanthroline(Py).Among them,Py-TPAMO exhibits the highest photoluminescence quantum yield of 78.4%and the smallest singlet-triplet energy gap,which is because the introduction of anisole does not cause significant molecule deformation for the excited Py-TPAMO.And Py-TPAMO-based OLEDs successfully realize a maximum external quantum efficiency of 25.5%with the emission peak at 605 nm.This work provides a series of candidate of donor fragments for the development of efficient long-wavelength TADF emitters. 展开更多
关键词 Organic light-emitting diodes Thermally activated delayed fluorescence Long-wavelength emission Triphenylamine Shallow HOMO energy level
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Automatic diagnosis of agromyzid leafminer damage levels using leaf images captured by AR glasses
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作者 Zhongru Ye Yongjian Liu +10 位作者 Fuyu Ye Hang Li Ju Luo Jianyang Guo Zelin Feng Chen Hong Lingyi Li Shuhua Liu Baojun Yang Wanxue Liu Qing Yao 《Journal of Integrative Agriculture》 2025年第9期3559-3573,共15页
Agromyzid leafminers cause significant economic losses in both vegetable and horticultural crops,and precise assessments of pesticide needs must be based on the extent of leaf damage.Traditionally,surveyors estimate t... Agromyzid leafminers cause significant economic losses in both vegetable and horticultural crops,and precise assessments of pesticide needs must be based on the extent of leaf damage.Traditionally,surveyors estimate the damage by visually comparing the proportion of damaged to intact leaf area,a method that lacks objectivity,precision,and reliable data traceability.To address these issues,an advanced survey system that combines augmented reality(AR)glasses with a camera and an artificial intelligence(AI)algorithm was developed in this study to objectively and accurately assess leafminer damage in the feld.By wearing AR glasses equipped with a voice-controlled camera,surveyors can easily flatten damaged leaves by hand and capture images for analysis.This method can provide a precise and reliable diagnosis of leafminer damage levels,which in turn supports the implementation of scientifically grounded and targeted pest management strategies.To calculate the leafminer damage level,the DeepLab-Leafminer model was proposed to precisely segment the leafminer-damaged regions and the intact leaf region.The integration of an edge-aware module and a Canny loss function into the DeepLabv3+model enhanced the DeepLab-Leafminer model's capability to accurately segment the edges of leafminer-damaged regions,which often exhibit irregular shapes.Compared with state-of-the-art segmentation models,the DeepLabLeafminer model achieved superior segmentation performance with an Intersection over Union(IoU)of 81.23%and an F1score of 87.92%on leafminer-damaged leaves.The test results revealed a 92.38%diagnosis accuracy of leafminer damage levels based on the DeepLab-Leafminer model.A mobile application and a web platform were developed to assist surveyors in displaying the diagnostic results of leafminer damage levels.This system provides surveyors with an advanced,user-friendly,and accurate tool for assessing agromyzid leafminer damage in agricultural felds using wearable AR glasses and an AI model.This method can also be utilized to automatically diagnose pest and disease damage levels in other crops based on leaf images. 展开更多
关键词 agromyzid leafminer plant leaf image damage level AR glasses DeepLabv3+model image segmentation
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