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A Prospective Study on Evaluating the Long-Term Effects of Childhood Vaccination from Birth to 13 Years Old in Kuwait
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作者 Nedaa A. Al-Khamees 《Health》 2024年第10期932-969,共38页
Background: To prevent infectious diseases and deaths of children, vaccinations play a crucial role in public health strategies in Kuwait. However, it remained uncertain to demonstrate the potential long-term health o... Background: To prevent infectious diseases and deaths of children, vaccinations play a crucial role in public health strategies in Kuwait. However, it remained uncertain to demonstrate the potential long-term health outcomes of vaccination, including neurodevelopmental disorders (NDD) and autism. This study aimed to evaluate the long-term health outcomes of vaccination among Kuwait children from birth to thirteen years old. Objectives: This study included the significant objectives: (1) to compare long-term health effects, including chronic and acute conditions for unvaccinated, partially vaccinated, and vaccinated children, and (2) to evaluate the association of vaccination with the neurodevelopmental disorders (NDD) and autism, and the preventable illnesses. Methods: This prospective study involved a sample of 976 children from Kuwait based on mothers’ reporting. Data collection about the vaccination status of children and various health outcomes relevant to chronic and acute illnesses was performed based on structured questionnaires through an online survey. However, participants were classified into unvaccinated (n = 40), partially vaccinated (n = 222), and fully vaccinated (n = 714). Statistical analyses, including the chi-square test, Odds Ratios (OR), 95% Confidence Interval (CI), and logistic regression, were performed using SAS (Version 9.4) to determine the associations between vaccination status and health outcomes among children. Results: The study disclosed that vaccinated children showed an increased diagnosis of chronic (allergic rhinitis, allergies, autism spectrum, eczema, neuro-developmental disorders, learning disability, ADHD, and any chronic condition) and acute (whooping cough, pneumonia, rubella, hepatitis A or B, measles, mumps, meningitis, influenza, rotavirus, cancer, chronic fatigue, Crohn’s disease, inflammatory bowel disease, conduct disorder, diabetes type 1 or 2, rheumatoid arthritis, obesity, seizures, hearing loss, polio, diphtheria, tetanus, and depression) illnesses than unvaccinated children. The fully vaccinated children showed an increased prevalence of influenza diagnosis, while partially vaccinated children were more likely to be diagnosed with rheumatoid arthritis than unvaccinated children. In contrast, unvaccinated were more likely to have been diagnosed with chickenpox and encephalopathy than fully and partially vaccinated. Males with chronic and acute conditions had a lower incidence of allergies and pneumonia, respectively, whereas females had a reduced prevalence of acute illnesses, such as whooping cough, inflammatory bowel disease, and hepatitis A or B among vaccinated (n = 936;combination of partially vaccinated and fully vaccinated) children. Regarding medication use and health service applications, vaccinated children were more likely to use medications for fever, antibiotics, and allergies. In addition, they showed an increased rate of sick visits and emergency visits in the past twelve months. On the other hand, factors like age (2 - 5 years, 6 - 9 years, and 10 - 13 years), birth type (cesarian), and mother suffering during pregnancy (gestational diabetes) were significantly associated with NDD (learning disability, autism spectrum, and attention deficient hyperactivity disorder) in the adjusted analysis. In the interaction model of age and birth type, age (6 - 9 years;OR 5.3, 95% CI: 1.1, 25.3) and mother suffering (gestational diabetes;OR 2.5, 95% CI: 1.2, 5.2) during pregnancy were associated with NDD. Conclusion: The findings of this study showed that there are some cases where the infection rate is higher among the vaccinated compared to unvaccinated children, or there are no significant differences between the two groups in Kuwait. Upon controlling the factors in the interaction model, the age of 6 to 9 years and gestational diabetic mothers during pregnancy were associated with the synergistic increment of odds with NDD. These data findings are recommended to verify a larger and diverse group of samples to optimize the vaccination on health outcomes in Kuwait children. 展开更多
关键词 VACCINATION Partial Vaccination Neurodevelopmental Disorders long-term Health Impacts AUTISM Chronic Conditions Acute Conditions KUWAIT
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Long-term effects of biodegradable versus durable polymercoated sirolimus-eluting stents on arterial wall morphology as assessed by virtual histology intravascular ultrasound
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作者 LIU Hui-liang,JIN Zhi-geng,LUO Jian-ping,MA Dong-xing, YANG Sheng-li,LIU Ying,HAN Wei,JING Li-min,MENG Rong-ying (General Hospital of Chinese Peoples Armed Police Forces, Beijing 100039,China) 《岭南心血管病杂志》 2011年第S1期54-54,共1页
Objectives To assess long-term coronary arterial response to biodegradable polymer-coated sirolimus-eluting stent(BSES) in vivo by using virtual histology intravascular ultrasound(VH-IVUS).Methods 41 patients were enr... Objectives To assess long-term coronary arterial response to biodegradable polymer-coated sirolimus-eluting stent(BSES) in vivo by using virtual histology intravascular ultrasound(VH-IVUS).Methods 41 patients were enrolled in this study and VH-IVUS was performed to assess the native artery vascular responses to BSES compared with durable polymer-coated SES(DSES) during long-term follow-up(median =8 months).The presence of necrotic core abutting to the lumen was evaluated at follow-up.Results With similar in-stent late luminal loss(0.15[0.06,0.30]vs 0.19[0.03, 0.30]mm,P=0.772),the overall incidence of necrotic core abutting to the lumen was significantly less in BSES than DSES group(44%vs.63%,P=0.019)(proximal 18%,stented site 14%and distal 12%in BSES group,proximal 19%, stented site 28%and distal 16%in DSES group).Compared with stented segments each other,the DSES -treated segments had a significant higher incidence of necrotic core abutting to the lumen through the stent struts(73%vs.36%, P=0.005).In addition,more multiple necrotic core abutting to the lumen was observed in DSES group(overall:63%vs. 36%,P=0.015).Furthermore,among the total number of stented segments with necrotic core abutting to the lumen, DSES -treated lesions had more multiple necrotic core abutting to the lumen through the stent struts than BSES -treated lesions in evidence(74%vs.33%,P=0.027).Conclusions By VH-IVUS analysis at follow-up,a greater frequency of stable lesion morphometry was shown in lesions treated with BSESs compared with lesions treated with DSESs.The major reason was BSES produced less toxicity to the arterial wall and facilitated neointimal healing as a result of polymer coating on drug-eluting stent(DES) surface biodegraded as time went by. 展开更多
关键词 IVUS long-term effects of biodegradable versus durable polymercoated sirolimus-eluting stents on arterial wall morphology as assessed
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Long-term effects of early antibiotic intervention on blood parameters,apparent nutrient digestibility, and fecal microbial fermentation profile in pigs with different dietary protein levels 被引量:9
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作者 Miao Yu Chuanjian Zhang +4 位作者 Yuxiang Yang Chunlong Mu Yong Su Kaifan Yu Weiyun Zhu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第1期175-186,共12页
Backgroud: This study aimed to determine the effects of early antibiotic intervention(EAI) on subsequent blood parameters, apparent nutrient digestibility, and fecal fermentation profile in pigs with different diet... Backgroud: This study aimed to determine the effects of early antibiotic intervention(EAI) on subsequent blood parameters, apparent nutrient digestibility, and fecal fermentation profile in pigs with different dietary crude protein(CP) levels. Eighteen litters of piglets(total 212) were randomly allocated to 2 groups and were fed a creep feed diet with or without in-feed antibiotics(olaquindox, oxytetracycline calcium and kitasamycin) from postnatal d 7 to d 42. On d 42, the piglets within the control or antibiotic group were mixed, respectively, and then further randomly assigned to a normal-(20%, 18%, and 14% CP from d 42 to d 77, d 77 to d 120, and d 120 to d 185,respectively) or a low-CP diet(16%, 14%, and 10% CP from d 42 to d 77, d 77 to d 120, and d 120 to d 185,respectively), generating 4 groups. On d 77(short-term) and d 185(long-term), serum and fecal samples were obtained for blood parameters, microbial composition and microbial metabolism analysis.Results: EAI increased(P 〈 0.05) albumin and glucose concentrations in low-CP diet on d 77, and increased(P 〈 0.05) urea concentration in normal-CP diet. On d 185, EAI increased(P 〈 0.05) globulin concentration in normal-CP diets, but decreased glucose concentration. For nutrient digestibility, EAI increased(P 〈 0.05)digestibility of CP on d 77. For fecal microbiota, the EAI as well as low-CP diet decreased(P 〈 0.05) E. coli count on d 77. For fecal metabolites, on d 77, EAI decreased(P 〈 0.05) total amines concentration but increased skatole concentration in low-CP diet. On d 185, the EAI increased(P 〈 0.05) putrescine and total amines concentrations in low-CP diets but reduced(P 〈 0.05) in the normal-CP diets. The low-CP diet decreased the concentrations of these compounds.Conclusions: Collectively, these results indicate that EAI has short-term effects on the blood parameters and fecal microbial fermentation profile. The effects of EAI varied between CP levels, which was characterized by the significant alteration of glucose and putrescine concentration. 展开更多
关键词 Antibiotics long term effect ANTIMICROBIAL Blood parameters Low protein diet Metabolites Microbiota
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Long-term effects of pattern scan laser pan-retinal photocoagulation on diabetic retinopathy in Chinese patients: a retrospective study 被引量:7
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作者 Chuang-Xin Huang Kun-Bei Lai +6 位作者 Li-Jun Zhou Zhen Tian Xiao-Jing Zhong Fa-Bao Xu Ya-Jun Gong Lin Lu Chen-Jin Jin 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第2期239-245,共7页
●AIM:To evaluate the long-term effects of pattern scan laser(PASCAL)pan-retinal photocoagulation(PRP)on diabetic retinopathy(DR)in Chinese patients.●METHODS:In this retrospective study,we evaluated clinical data of ... ●AIM:To evaluate the long-term effects of pattern scan laser(PASCAL)pan-retinal photocoagulation(PRP)on diabetic retinopathy(DR)in Chinese patients.●METHODS:In this retrospective study,we evaluated clinical data of 29 patients(53 eyes)with severe non-proliferative DR(SNPDR)or proliferative DR(PDR)who received PRP and follow-up at our hospital from 2008 to 2013.Sixteen patients(29 eyes)received PASCAL PRP and 13 patients(24 eyes)received 100-ms conventional laser PRP.●RESULTS:After long-term follow-up(mean,min-max days:719.8,290-1666 for PASCAL PRP vs 743.5,240-1348 for conventional PRP,P=0.569),patients receiving PASCAL PRP required fewer photocoagulation sessions than the conventional PRP group(2.6±1.0 vs 3.9±0.9,P<0.01).Best corrected visual acuity(BCVA)was reduced slightly in PASCAL PRP group while reduced significantly in conventional PRP group.At last visit,24 eyes in the PASCAL group(88.9%)and 21 eyes in the conventional group(91.7%)were improved or stable.Two eyes in PASCAL PRP group(7.4%)and 3 eyes in the conventional PRP group(12.5%)developed vitreous hemorrhage or vitreous fibrovascular proliferation.●CONCLUSION:PASCAL PRP is as effective and may be more conducive to maintaining visual acuity with less treatment sessions for DR treatment compared to conventional laser PRP. 展开更多
关键词 PROLIFERATIVE DIABETIC RETINOPATHY severe non-proliferative DIABETIC RETINOPATHY pattern SCAN laser pan-retinal photocoagulation clinical effect
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Long-term effects of metformin use in gestational diabetes mellitus on offspring health
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作者 Ayan Roy Jayaprakash Sahoo 《World Journal of Diabetes》 SCIE 2021年第11期1812-1817,共6页
Metformin is the first-line drug for the treatment of type 2 diabetes mellitus,but its role in gestational diabetes mellitus(GDM)management is not clear.Recent evidence suggests a certain beneficial effect of metformi... Metformin is the first-line drug for the treatment of type 2 diabetes mellitus,but its role in gestational diabetes mellitus(GDM)management is not clear.Recent evidence suggests a certain beneficial effect of metformin in the treatment of GDM,but a high treatment failure rate leads to the initiation of additional medications,such as insulin.Moreover,since metformin crosses the placental barrier and reaches a significant level in the fetus,it is likely to influence the fetal metabolic milieu.The evidence indicates the long-term safety in children exposed to metformin in utero except for mild adverse anthropometric profiles.Diligent follow-up of metformin-exposed offspring is warranted from the clinician’s point of view. 展开更多
关键词 ANTHROPOMETRY FETAL Gestational diabetes mellitus long-term METFORMIN OFFSPRING
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Long-term effects of management systems on crop yield and soil physical properties of semi-arid tropics of Vertisols
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作者 Prabhakar Pathak Suhas P Wani Raghavendra Rao Sudi 《Agricultural Sciences》 2011年第4期435-442,共8页
Long-term experiments can be used to assess management induced changes in soil properties and sustainability of the management system in terms of the productivity. Such data are scanty, especially in the semi-arid tro... Long-term experiments can be used to assess management induced changes in soil properties and sustainability of the management system in terms of the productivity. Such data are scanty, especially in the semi-arid tropics (SAT) region. A long-term experiment established in 1976 at ICRISAT in India on Vertisols with two management treatments;improved management (IM), comprising semi-permanent broadbed and furrow (BBF) landform with minimum tillage and improved cropping practices;and traditional management (TM) system comprising keeping the land fallow during the rainy season and sowing on flat landform during post-rainy season with traditional cropping practices, was sampled after 24 and 34 years for soil physical and hydrological properties. Results showed that both in short-and long-term the management systems had profound effect on crop yields. Also in the long-term IM and TM management systems had significant effect on several soil physical and hydrological properties. Throughout the soil profile IM systems had significantly lower bulk density, significantly higher porosity, substantially lower penetration resistance both at 5 cm (1 and 8 MPa) and 15 cm depths (8 and 15 MPa), significantly higher infiltration and sorptivity and significantly larger mean weight diameter of 4.3 mm compared to 2.8 mm for soils under TM. However, management systems had no significant effect on moisture holding capacities both at 0.033 and 1.5 MPa. Significant differences between the improved and traditional systems were observed in the size and pattern of soil surface cracks. Over the long-term, the improved management systems has very favorable effects on soil physical and hydrological properties and on the soil surface cracking and its patterns, thereby contributing to higher productivity. 展开更多
关键词 Broadbed and FURROW System Minimum TILLAGE long-term Experiment SUSTAINABILITY
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Verification of the Physiological Therapeutic Effects of Harvesting Activities in a Patient with Moderate Alzheimer’s Disease with Long-Term Agricultural Experience
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作者 Kikuo Eguchi Seigo Koura +1 位作者 Nao Eguchi Akihiko Kondou 《Open Journal of Therapy and Rehabilitation》 2024年第3期236-244,共9页
Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting ac... Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting activities as a part of their treatment. The patients became calmer and began to smile not only after but also before and during harvesting activity. Therefore, this study aimed to measure autonomic nervous system (ANS) responses over time in a female patient in her 80s with moderate Alzheimer’s disease (AD) who had experience in farming when performing harvesting activities. Additionally, this study aimed to consider factors associated with changes in ANS responses over time and to verify the physiological therapeutic effects of harvesting activities. Methods: An OT with more than 10 years of experience and a good relationship with the patient conducted one-on-one sessions with the patient. Harvesting activity was performed in a courtyard with trees. The patient harvested lettuce (three lettuce plants) grown in a planter while sitting on a chair. Additionally, the planter was set up on a desk. ANS responses were measured over time from before to after the activity for different events at six time periods. Changes in the patient’s ANS responses were assessed during each period. Results: With the involvement of environmental factors and OT during harvesting activities, parasympathetic nervous system (PNS) activity significantly increased. This may lead to improved mental stability. Conclusion: The findings of this study indicate that implementing harvesting activities may have a positive effect on the PNS in patients with AD with long-term agricultural experience. However, further studies with a larger sample size and multidimensional evaluations are needed. 展开更多
关键词 Alzheimer’s Disease Autonomic Nervous Response Harvesting Activity Therapeutic effects
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Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis 被引量:1
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作者 Andreas Konrad Shahab Alizadeh +7 位作者 Abdolhamid Daneshjoo Saman Hadjizadeh Anvar Andrew Graham Ali Zahiri Reza Goudini Chris Edwards Carina Scharf David George Behm 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期186-194,共9页
Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence... Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in flexibility.Thus,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch training.Methods:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect meta-analysis.Moreover,by applying a mixed-effect model,we performed the respective subgroup analyses.To find potential relationships between stretch duration or age and effect sizes,we performed a meta-regression.Results:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic stretching.Moreover,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to males.However,further moderating analysis showed no significant relation or difference.Conclusion:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be applied.Something to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were found to play a significant role in ROM yields. 展开更多
关键词 FLEXIBILITY long-term stretching Stretch training
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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:6
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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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Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020 被引量:1
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作者 ZHU Yuanyuan ZHANG Yan ZHU Xiaohua 《Chinese Geographical Science》 SCIE CSCD 2024年第1期181-194,共14页
Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research ob... Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern. 展开更多
关键词 dietary structure structural evolution carbon emission effects carbon neutrality China
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Simulation of the Ecosystem Productivity Responses to Aerosol Diffuse Radiation Fertilization Effects over the Pan-Arctic during 2001–19 被引量:1
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作者 Zhiding ZHANG Xu YUE +3 位作者 Hao ZHOU Jun ZHU Yadong LEI Chenguang TIAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期84-96,共13页
The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).Whil... The pan-Arctic is confronted with air pollution transported from lower latitudes.Observations have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).While such DRFEs have been explored at low to middle latitudes,the aerosol impacts on pan-Arctic ecosystems and the contributions by anthropogenic and natural emission sources remain less quantified.Here,we perform regional simulations at 0.2o×0.2ousing a well-validated vegetation model(Yale Interactive terrestrial Biosphere,YIBs)in combination with multi-source of observations to quantify the impacts of aerosol DRFEs on the net primary productivity(NPP)in the pan-Arctic during 2001-19.Results show that aerosol DRFEs increase pan-Arctic NPP by 2.19 Pg C(12.8%)yr^(-1)under clear-sky conditions,in which natural and anthropogenic sources contribute to 8.9% and 3.9%,respectively.Under all-sky conditions,such DRFEs are largely dampened by cloud to only 0.26 Pg C(1.24%)yr^(-1),with contributions of 0.65% by natural and 0.59% by anthropogenic species.Natural aerosols cause a positive NPP trend of 0.022% yr^(-1)following the increased fire activities in the pan-Arctic.In contrast,anthropogenic aerosols induce a negative trend of-0.01% yr^(-1)due to reduced emissions from the middle latitudes.Such trends in aerosol DRFEs show a turning point in the year of 2007 with more positive NPP trends by natural aerosols but negative NPP trends by anthropogenic aerosols thereafter.Though affected by modeling uncertainties,this study suggests a likely increasing impact of aerosols on terrestrial ecosystems in the pan-Arctic under global warming. 展开更多
关键词 diffuse radiation fertilization effects anthropogenic aerosols natural aerosols pan-Arctic net primary productivity
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Stabilizing High-Nickel Cathodes via Interfacial Hydrogen Bonding Effects Using a Hydrofluoric Acid-Scavenging Separator
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作者 Shijie Zhong Liwei Dong +6 位作者 Botao Yuan Yueyao Dong Qun Li Yuanpeng Ji Yuanpeng Liu Jiecai Han Weidong He 《Engineering》 SCIE EI CAS CSCD 2024年第8期117-126,共10页
Nickel-rich layered Li transition metal oxides are the most promising cathode materials for high-energydensity Li-ion batteries.However,they exhibit rapid capacity degradation induced by transition metal dissolution a... Nickel-rich layered Li transition metal oxides are the most promising cathode materials for high-energydensity Li-ion batteries.However,they exhibit rapid capacity degradation induced by transition metal dissolution and structural reconstruction,which are associated with hydrofluoric acid(HF)generation from lithium hexafluorophosphate decomposition.The potential for thermal runaway during the working process poses another challenge.Separators are promising components to alleviate the aforementioned obstacles.Herein,an ultrathin double-layered separator with a 10 lm polyimide(PI)basement and a 2 lm polyvinylidene difluoride(PVDF)coating layer is designed and fabricated by combining a nonsolvent induced phase inversion process and coating method.The PI skeleton provides good stability against potential thermal shrinkage,and the strong PI-PVDF bonding endows the composite separator with robust structural integrity;these characteristics jointly contribute to the extraordinary mechanical tolerance of the separator at elevated temperatures.Additionally,unique HF-scavenging effects are achieved with the formation of-CO…H-F hydrogen bonds for the abundant HF coordination sites provided by the imide ring;hence,the layered Ni-rich cathodes are protected from HF attack,which ultimately reduces transition metal dissolution and facilitates long-term cyclability of the Ni-rich cathodes.Li||NCM811 batteries(where“NCM”indicates LiNi_(x)Co_(y)Mn_(1-x-y)O_(2))with the proposed composite separator exhibit a 90.6%capacity retention after 400 cycles at room temperature and remain sustainable at 60℃with a 91.4%capacity retention after 200 cycles.By adopting a new perspective on separators,this study presents a feasible and promising strategy for suppressing capacity degradation and enabling the safe operation of Ni-rich cathode materials. 展开更多
关键词 Nickel-rich cathodes Composite separator HF scavenging Transition metal dissolution long-term cyclability
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Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement
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作者 Yuanyuan Wang Xinzhu Dai +5 位作者 Xingling Chen Dan Zhang Guiqing Lin Yuanhang Zhou Tianyi Wang Yulong Cui 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期146-162,共17页
Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban... Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future. 展开更多
关键词 Species diversity Forest characteristics Biomass carbon sink Forest-type effect Urbanization effect Urban forests
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Health Effects of Extreme Low Temperatures and Cold Waves on Respiratory Diseases
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作者 Zongrui Liu Yuxia Ma +4 位作者 Yuhan Zhao Wanci Wang Pengpeng Qin Jie Yang Bowen Cheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第6期682-685,共4页
Climate change is the most significant threat to public health and exerts myriad influences on health,including the occurrence of extreme temperature events.Studies have demonstrated that populations will experience s... Climate change is the most significant threat to public health and exerts myriad influences on health,including the occurrence of extreme temperature events.Studies have demonstrated that populations will experience significantly severe cold waves in the future^([1]),increasing the risk of respiratory diseases. 展开更多
关键词 EXTREME effects events.
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Tilted Perpendicular Anisotropy-Induced Spin-Orbit Ratchet Effects
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作者 陈彬 龙垣图 +6 位作者 聂宇林 凌姿瑀 马天平 张瑞轩 吴义政 骆泳铭 王宁宁 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第7期181-186,I0001,I0002,I0003,共9页
Using micromagnetic simulations, we demonstrate the tilted perpendicular anisotropy-induced spin-orbit ratchet effect. In spin-orbit torque(SOT)-induced magnetization switching, the critical currents required to switc... Using micromagnetic simulations, we demonstrate the tilted perpendicular anisotropy-induced spin-orbit ratchet effect. In spin-orbit torque(SOT)-induced magnetization switching, the critical currents required to switch between the two magnetization states(upward and downward magnetization) are asymmetric. In addition, in the nanowire structure, tilted anisotropy induces formation of tilted domain walls(DWs). The tilted DWs exhibit a ratchet behavior during motion. The ratchet effect during switching and DW motions can be tuned by changing the current direction with respect to the tilting direction of anisotropy. The ratchet motion of the DWs can be used to mimic the leaky-integrate-fire function of a biological neuron, especially the asymmetric property of the “potential” and “reset” processes. Our results provide a full understanding of the influence of tilted perpendicular anisotropy on SOT-induced magnetization switching and DW motion, and are beneficial for designs of further SOT-based devices. 展开更多
关键词 MOTION effect MAGNETIZATION
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Effects of long-term grazing exclusion on vegetation structure,soil water holding capacity,carbon and nitrogen sequestration capacity in an alpine meadow on the Tibetan Plateau 被引量:2
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作者 YANG Yong-sheng ZHANG Fa-wei +5 位作者 XIE Xian-rong WANG Jun-bang LI Ying-nian HUANG Xiao-tao LI Hui-ting ZHOU Hua-kun 《Journal of Mountain Science》 SCIE CSCD 2023年第3期779-791,共13页
Grazing exclusion is one of the primary management practices used to restore degraded grasslands on the Tibetan Plateau.However,to date,the effects of long-term grazing exclusion measures on the process of restoring d... Grazing exclusion is one of the primary management practices used to restore degraded grasslands on the Tibetan Plateau.However,to date,the effects of long-term grazing exclusion measures on the process of restoring degraded alpine meadows have not been evaluated.In this study,moderately degraded plots,in which the vegetation coverage was approximately 65%and the dominant plant species was Potentilla anserina L,with grazing exclusion for 2 to 23 years,were selected in alpine meadows of Haibei in Qinghai-Tibet Plateau.Plant coverage,plant height,biomass,soil bulk density,saturated water content,soil organic carbon(SOC)and total nitrogen(TN)were evaluated.The results were as follows:(1)With aboveground biomass and total saturated water content at 0-40 cm depth,the average SOC and TN contents in moderately degraded alpine meadows increased as a power function,and the plant height increased as a log function.(2)The average soil bulk density at 0-40 cm depth first decreased and then increased with increasing grazing exclusion duration,and the minimum value of 0.90 g·cm^(-3) was reached at 15.23 years.The plant coverage,total belowground biomass at 0-40 cm depth,total aboveground and belowground biomass first increased and then decreased,their maximum values(80.49%,2452.92g·m^(-2),2891.06 g·m^(-2))were reached at 9.41,9.46 and 10.25 years,respectively.Long-term grazing exclusion is apparently harmful for the sustainable restoration of degraded alpine meadows.The optimal duration of grazing exclusion for the restoration of moderately degraded alpine meadows was 10 years.This research suggests that moderate disturbance should be allowed in moderately degraded alpine meadows after 10years of grazing exclusion. 展开更多
关键词 long-term grazing exclusion Soil water holdingcapacity Soilcarbonand nitrogen sequestration BIOMASS Alpine meadow
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Effects of Collocational Congruency,Frequency and L2 Proficiency on the Processing of English Adjective-Noun Collocations
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作者 Lianrui YANG Qun ZHANG +1 位作者 Ni LI Ying CHEN 《Chinese Journal of Applied Linguistics》 2024年第3期393-413,524,共22页
The present study investigates the effects of congruency and frequency on adjective-noun collocational processing for Chinese learners of English at two proficiency levels based on the data obtained in an online accep... The present study investigates the effects of congruency and frequency on adjective-noun collocational processing for Chinese learners of English at two proficiency levels based on the data obtained in an online acceptability judgment task.The subject pool of this research included 60 English majors studying at a university in China;30 were selected as a higher-proficiency group and 30 as a lower-proficiency group according to their Vocabulary Levels Test(Schmitt et al.,2001)scores and their self-reported proficiency in English.The experimental materials were programmed to E-prime 2.0 and included six types of collocations:(1)15 high-frequency congruent collocations,(2)15 low-frequency congruent collocations,(3)15 high-frequency incongruent collocations,(4)15 low-frequency incongruent collocations,(5)15 Chinese-only items,and(6)75 unrelated items for baseline data.The collected response times(RTs)and accuracy rates data were statistically analyzed by the use of an ANOVA test and pairwise comparisons through SPSS 16.0 software.The results revealed that:(1)the adjective-noun collocational processing of Chinese English learners is influenced by collocational frequency,congruency and L2 proficiency;(2)the processing time is affected by the interaction of congruency and frequency;and(3)the interactive effect of L2 proficiency in conjunction with congruency and frequency also influences the processing quality. 展开更多
关键词 adjective-noun collocations congruency effects frequency effects L2 proficiency
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Cation effects in electrocatalytic reduction reactions:Recent advances
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作者 Qinghui Ren Liang Xu +4 位作者 Mengyu Lv Zhiyuan Zhang Zhenhua Li Mingfei Shao Xue Duan 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期16-32,共17页
Electrocatalytic reduction reactions,powered by clean energy sources such as solar energy and wind,offer a sustainable method for converting inexpensive feedstocks(e.g.,CO_(2),N_(2)/NO_(x),organics,and O_(2))into high... Electrocatalytic reduction reactions,powered by clean energy sources such as solar energy and wind,offer a sustainable method for converting inexpensive feedstocks(e.g.,CO_(2),N_(2)/NO_(x),organics,and O_(2))into high-value-added chemicals or fuels.The design and modification of electrocatalysts have been widely implemented to improve their performance in these reactions.However,bottle-necks are encountered,making it challenging to further improve performance through catalyst development alone.Recently,cations in the electrolyte have emerged as critical factors for tuning both the activity and product selectivity of reduction reactions.This review summarizes recent advances in understanding the role of cation effects in electrocatalytic reduction reactions.First,we introduce the mechanisms underlying cation effects.We then provide a comprehensive overview of their application in electroreduction reactions.Characterization techniques and theoretical calcula-tion methods for studying cation effects are also discussed.Finally,we address remaining challeng-es and future perspectives in this field.We hope that this review offers fundamental insights and design guidance for utilizing cation effects,thereby advancing their development. 展开更多
关键词 ELECTROCATALYSIS Reduction reaction Cation effect MECHANISM APPLICATION
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Protective effects of baffles with different positions,row spacings,heights on debris flow impact
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作者 SUN Xinpo CHEN Min +5 位作者 BI Yuzhang ZHENG Lu CHE Chi XU Ao TIAN Zijian JIANG Zheyuan 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2352-2367,共16页
The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow movement.Consequently,they are widely used for protection against natural haza... The baffle effectively slowed down debris flow velocity,reduced its kinetic energy,and significantly shortened the distance of debris flow movement.Consequently,they are widely used for protection against natural hazards such as landslides and mudslides.This study,based on the threedimensional DEM(Discrete Element Method),investigated the impact of different baffle positions on debris flow protection.Debris flow velocity and kinetic energy variations were studied through single-factor experiments.Suitable baffle positions were preliminarily selected by analyzing the influence of the first-row baffle position on the impact force and accumulation mass of debris flow.Subsequently,based on the selected baffle positions and four factors influencing the effectiveness of baffle protection(baffle position(P),baffle height(h),row spacing(S_(r)),and angle of transit area(α)),an orthogonal design was employed to further explore the optimal arrangement of baffles.The research results indicate that the use of a baffle structure could effectively slow down the motion velocity of debris flows and dissipate their energy.When the baffle is placed in the transit area,the impact force on the first-row baffle is greater than that when the baffle is placed in the deposition area.Similarly,when the baffle is placed in the transit area,the obstruction effect on debris flow mass is also greater than that when the baffle is placed in the deposition area.Through orthogonal experimental range analysis,when the impact on the first row of baffles is used as the evaluation criterion,the importance of each influencing factor is ranked asα>P>S_(r)>h.When the mass of debris flow behind the baffle is regarded as the evaluation criterion,the rank is changed to P>α>S_(r)>h.The experimental simulation results show that the optimal baffle arrangement is:P_(5),S_(r)=16,α=35°,h=9. 展开更多
关键词 Debris flow BAFFLE Protective effect Discrete element
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Kinetics insights into size effects of carbon nanotubes'growth and their supported platinum catalysts for 4,6-dinitroresorcinol hydrogenation
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作者 Yan Zhang Xiangxue Zhang +6 位作者 Keng Sang Wenyao Chen Gang Qian Jing Zhang Xuezhi Duan Xinggui Zhou Weikang Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期133-140,共8页
Size effects are a well-documented phenomenon in heterogeneous catalysis,typically attributed to alterations in geometric and electronic properties.In this study,we investigate the influence of catalyst size in the pr... Size effects are a well-documented phenomenon in heterogeneous catalysis,typically attributed to alterations in geometric and electronic properties.In this study,we investigate the influence of catalyst size in the preparation of carbon nanotube(CNT)and the hydrogenation of 4,6-dinitroresorcinol(DNR)using Fe_(2)O_(3)and Pt catalysts,respectively.Various Fe_(2)O_(3)/Al_(2)O_(3)catalysts were synthesized for CNT growth through catalytic chemical vapor deposition.Our findings reveal a significant influence of Fe_(2)O_(3)nanoparticle size on the structure and yield of CNT.Specifically,CNT produced with Fe_(2)O_(3)/Al_(2)O_(3)containing 28%(mass)Fe loading exhibits abundant surface defects,an increased area for metal-particle immobilization,and a high carbon yield.This makes it a promising candidate for DNR hydrogenation.Utilizing this catalyst support,we further investigate the size effects of Pt nanoparticles on DNR hydrogenation.Larger Pt catalysts demonstrate a preference for 4,6-diaminoresorcinol generation at(100)sites,whereas smaller Pt catalysts are more susceptible to electronic properties.The kinetics insights obtained from this study have the potential to pave the way for the development of more efficient catalysts for both CNT synthesis and DNR hydrogenation. 展开更多
关键词 KINETICS Size effects Catalytic hydrogenation Active site
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