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Effect of In-home Fortification of Complementary Feeding on Intellectual Development of Chinese Children 被引量:5
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作者 CHUN-MING CHEN, YU-YING WANG, AND SU-YING CHANG Chinese Center for Disease Control and Prevention, Beijing 100050, China 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第2期83-91,共9页
Objective To explore the effect of in-home fortification of complementary feeding on intellectual development of Chinese children aged below 24 months. Methods One thousand and four hundred seventy eight children aged... Objective To explore the effect of in-home fortification of complementary feeding on intellectual development of Chinese children aged below 24 months. Methods One thousand and four hundred seventy eight children aged 4-12 months were recruited and divided into study groups (formula 1 group and formula 2 group) and control group. In two study groups, in addition to the usual complementary food, children were fed with a sachet of fortified food supplement each day. Protein and micronutrients were provided in formula 1 group. Formula 2 group had the same energy intake as the formula 1 group . In addition to measurement of physical growth and detection of hemoglobin level, Development Quotient (DQ) or Intelligence Quotient (IQ) was assessed. Results The DQ of children aged below 24 months was 97.2, 95.5, and 93.8 in formula 1 group, formula 2 group and control group, respectively, and the differences were statistically significant (P〈0.05). The DQ of children in formula 1 group, formula 2 group, and control group was 92.7, 90.4, and 88.3 respectively in the first follow up showing statistically significant differences (P〈0.05). And, DQ of children in formula 1 group, formula 2 group and control group were 96.7, 94.5, and 93.7 respectively in the second follow up, showing statistically significant differences (P〈0.05). FulI-IQ of children in the formula 1 group was 3.1 and 4.5 points higher than that in formula 2 group and in control group respectively. Verbal IQ of children in the formula 1 group was 2.1 and 5 points higher than that in formula 2 group and control group respectively. Performance IQ was 2.5 and 3.1 points higher than that in formula 2 group and control group respectively. All above mentioned comparisons were statistically significant. Conclusion Fortification of complementary feeding showed persistent effect on intelligence development of young children which could persist to 6 years of age. The critical time for correction of anemia could be under 18 months. 展开更多
关键词 complementary feeding SUPPLEMENT DEVELOPMENT ANEMIA INFANT
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Effects of Nutrient Fortified Complementary Food Supplements on Anemia of Infants and Young Children in Poor Rural of Gansu 被引量:5
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作者 YU-YING WANG CHUN-MING CHEN +2 位作者 FU-ZHEN WANG MEI JIA KE-AN WANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第3期194-200,共7页
Objective To assess the effectiveness of complementary food supplements with protein and multi-micronutrients on hemoglobin and anemia in infants and young children. Methods In 5 poor counties of Gansu, 984 children a... Objective To assess the effectiveness of complementary food supplements with protein and multi-micronutrients on hemoglobin and anemia in infants and young children. Methods In 5 poor counties of Gansu, 984 children aged 6-12 months were enrolled and divided into two groups. In addition to the usual home-made complementary food, all the children were fed one sachet of either Formula Ⅰ or Formula Ⅱ supplements each day. Protein and micronutrients were provided in Formula Ⅰ, while the same energy intake was secured in Formula Ⅱ as in Formula Ⅰ. A massive dose of vitamin A was supplemented to all the children every 6 months. Hemoglobin test was done at the same time. Results Prevalence of anemia was about 35% in both Formula Ⅰ and Formula Ⅱ group at baseline, and there were no differences in hemoglobin concentration between the two groups, During the 6-month and 12-month supplementation, hemoglobin of children in Formula Ⅰ group was higher than that in Formula Ⅱ group (P〈0.05), and hemoglobin increase in Formula Ⅰ group was significantly higher than that in Formula Ⅱ group (P〈0.001). After 6- and 12-mouth supplementation, the prevalence of anemia in Formula Ⅰ group dropped to 19.1% and 8.2% respectively, and it was 28.0% and 12.4% in Formula 2 group. The prevalence of anemia in Formula Ⅰ group was significantly lower than that in Formula Ⅱ group (P〈0.05). After adjusting age and hemoglobin level at baseline, the hemoglobin increase at age of 24 months in formula 1 group was higher (10.7 g/L vs 7.9 g/L, P〈0.0001). Conclusion Micronutrient fortified complementary food supplements, with large-dose vitamin A, is effective for children aged 6-12 months in terms of iron deficiency prevention. 展开更多
关键词 Food fortification complementary food supplements Infants and young children HEMOGLOBIN Iron deficiency anemia
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Effective forecast of Northeast Pacific sea surface temperature based on a complementary ensemble empirical mode decomposition–support vector machine method 被引量:1
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作者 LI Qi-Jie ZHAO Ying +1 位作者 LIAO Hong-Lin LI Jia-Kang 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第3期261-267,共7页
The sea surface temperature (SST) has substantial impacts on the climate; however, due to its highly nonlinear nature, evidently non-periodic and strongly stochastic properties, it is rather difficult to predict SST... The sea surface temperature (SST) has substantial impacts on the climate; however, due to its highly nonlinear nature, evidently non-periodic and strongly stochastic properties, it is rather difficult to predict SST. Here, the authors combine the complementary ensemble empirical mode decomposition (CEEMD) and support vector machine (SVM) methods to predict SST. Extensive tests from several different aspects are presented to validate the effectiveness of the CEEMD-SVM method. The results suggest that the new method works well in forecasting Northeast Pacific SST at a 12-month lead time, with an average absolute error of approximately 0.3℃ and a correlation coefficient of 0.85. Moreover, no spring predictability barrier is observed in our experiments. 展开更多
关键词 Sea surface temperature complementary ensemble empirical mode decomposition support vector machine PREDICTION
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Ge Complementary Tunneling Field-Effect Transistors Featuring Dopant Segregated NiGe Source/Drain 被引量:1
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作者 Junkang Li Yiming Qu +3 位作者 Siyu Zeng Ran Cheng Rui Zhang Yi Zhao 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第11期70-73,共4页
Ge complementary tunneling field-effect transistors(TFETs) are fabricated with the NiGe metal source/drain(S/D) structure. The dopant segregation method is employed to form the NiGe/Ge tunneling junctions of suffi... Ge complementary tunneling field-effect transistors(TFETs) are fabricated with the NiGe metal source/drain(S/D) structure. The dopant segregation method is employed to form the NiGe/Ge tunneling junctions of sufficiently high Schottky barrier heights. As a result, the Ge p-and n-TFETs exhibit decent electrical properties of large ON-state current and steep sub-threshold slope(S factor). Especially, I_d of 0.2 μA/μm is revealed at V_g-V_(th) = V_d = ±0.5 V for Ge pTFETs,with the S factor of 28 mV/dec at 7 K. 展开更多
关键词 Ge complementary Tunneling Field-effect Transistors Featuring Dopant Segregated NiGe Source/Drain MOSFET
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Effects of Moxibustion at Complementary Acupoints on Synovial Tissue Inflammation of CIA Rats
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作者 Yaying CUI Zhixin YANG Zefan LONG 《Medicinal Plant》 CAS 2018年第5期80-82,共3页
[Objectives] This study aimed to explore the effects of moxibustion at the Yanglingquan and Yinlingquan points on thickness of the left foot and synovial tissue inflammation of collagen-induced arthritis( CIA) rats,an... [Objectives] This study aimed to explore the effects of moxibustion at the Yanglingquan and Yinlingquan points on thickness of the left foot and synovial tissue inflammation of collagen-induced arthritis( CIA) rats,and to explore the therapeutic effect of moxibustion at complementary acupoints on rheumatoid arthritis( RA). [Methods] Total 32 Wistar rats were selected. Among them,8 rats were selected randomly using the randomized digital method as the blank control( K),and the remaining were subjected to modeling. After the successful establishment of the CIA model,the 24 rats were randomly and evenly divided into model group( M),Yanglingquan and Yinlingquan group( AB) and Shenshu and Zusanli group( CD). The rats in the moxibustion groups were subjected to bilateral synchronous moxibustion once every two days( 2 mg refined moxa/cone,5 cones/( point·d)),for total 10 times. The left plantar thickness of each rat was measured before modeling,after modeling,and after the last intervention,respectively. After the last intervention,the situation of synovial tissue inflammation in each rat of the treatment group was inspected. [Results] Compared with that of the control group,the left foot thickness of each group of rats that were modeled all increased significantly( P < 0. 05). And the synovial tissue showed different degrees of inflammatory infiltration,fibrous hyperplasia,and angiogenes. After the intervention ended,compared with that in the M group,the left foot thickness in the AB and CD treatment groups reduced significantly( P < 0. 05). The inflammatory infiltration,fibrous hyperplasia,and angiogenes of the synovial tissue decreased. Between the two moxibustion groups,the thickness of the left foot in group AB decreased compared with group CD( P < 0. 05). The inflammatory infiltration,fibrous hyperplasia and angiogenes in group AB decreased compared with those in group CD. [Conclusions] Moxibustion at the complementary acupoints of Yanglingquan and Yinlingquan,Shenshu and Zusanli both showed good improvement effect on CIA rats. In terms of left foot thickness and synovial tissue inflammation,the treatment group AB was superior to the group CD,and the specific mechanism needs further study. 展开更多
关键词 complementary ACUPOINTS MOXIBUSTION Yinlingquan YANGLINGQUAN
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240 nm AlGaN-based deep ultraviolet micro-LEDs:size effect versus edge effect 被引量:2
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作者 Shunpeng Lu Jiangxiao Bai +6 位作者 Hongbo Li Ke Jiang Jianwei Ben Shanli Zhang Zi-Hui Zhang Xiaojuan Sun Dabing Li 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期55-62,共8页
240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge ef... 240 nm AlGaN-based micro-LEDs with different sizes are designed and fabricated.Then,the external quantum efficiency(EQE)and light extraction efficiency(LEE)are systematically investigated by comparing size and edge effects.Here,it is revealed that the peak optical output power increases by 81.83%with the size shrinking from 50.0 to 25.0μm.Thereinto,the LEE increases by 26.21%and the LEE enhancement mainly comes from the sidewall light extraction.Most notably,transversemagnetic(TM)mode light intensifies faster as the size shrinks due to the tilted mesa side-wall and Al reflector design.However,when it turns to 12.5μm sized micro-LEDs,the output power is lower than 25.0μm sized ones.The underlying mechanism is that even though protected by SiO2 passivation,the edge effect which leads to current leakage and Shockley-Read-Hall(SRH)recombination deteriorates rapidly with the size further shrinking.Moreover,the ratio of the p-contact area to mesa area is much lower,which deteriorates the p-type current spreading at the mesa edge.These findings show a role of thumb for the design of high efficiency micro-LEDs with wavelength below 250 nm,which will pave the way for wide applications of deep ultraviolet(DUV)micro-LEDs. 展开更多
关键词 ALGAN deep ultraviolet micro-LEDs light extraction efficiency size effect edge effect
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Comparing the Effects of Interactive and Noninteractive Complementary Nutrients on Growth in a Chemostat
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作者 James P. Braselton Martha L. Abell Lorraine M. Braselton 《Open Journal of Applied Sciences》 2013年第5期323-331,共9页
We compare the effects of interactive and noninteractive complementary nutrients on the growth of an organism in the chemostat. We also compare these two situations to the case when the nutrients are substitutable. In... We compare the effects of interactive and noninteractive complementary nutrients on the growth of an organism in the chemostat. We also compare these two situations to the case when the nutrients are substitutable. In previous studies, complementary nutrients have been assumed to be noninteractive. However, more recent research indicates that some complementary nutrient relationships are interactive. We show that interactive complementary and substitutable nutrients can lead to higher population densities than do noninteractive complementary nutrients. We numerically illustrate that if the washout rate is high, an organism can persist at higher densities when the complementary nutrients are interactive than when they are noninteractive, which can result in the extinction of the organism. Finally, we present an example by making a small adjustment to the model that leads to a single nutrient model with an intermediate metabolite of the original substrate as the nutrient for the organism. 展开更多
关键词 CHEMOSTAT GROWTH Dual Substrate complementary NUTRIENTS SUBSTITUTABLE NUTRIENTS
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Evaluation of the intracellular lipid-lowering effect of polyphenols extract from highland barley in HepG2 cells 被引量:3
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作者 Yijun Yao Zhifang Li +2 位作者 Bowen Qin Xingrong Ju Lifeng Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期454-461,共8页
Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinat... Active ingredients from highland barley have received considerable attention as natural products for developing treatments and dietary supplements against obesity.In practical application,the research of food combinations is more significant than a specific food component.This study investigated the lipid-lowering effect of highland barley polyphenols via lipase assay in vitro and HepG2 cells induced by oleic acid(OA).Five indexes,triglyceride(TG),total cholesterol(T-CHO),low density lipoprotein-cholesterol(LDL-C),aspartate aminotransferase(AST),and alanine aminotransferase(ALT),were used to evaluate the lipidlowering effect of highland barley extract.We also preliminary studied the lipid-lowering mechanism by Realtime fluorescent quantitative polymerase chain reaction(q PCR).The results indicated that highland barley extract contains many components with lipid-lowering effects,such as hyperoside and scoparone.In vitro,the lipase assay showed an 18.4%lipase inhibition rate when the additive contents of highland barley extract were 100μg/m L.The intracellular lipid-lowering effect of highland barley extract was examined using 0.25 mmol/L OA-induced HepG2 cells.The results showed that intracellular TG,LDL-C,and T-CHO content decreased by 34.4%,51.2%,and 18.4%,respectively.ALT and AST decreased by 51.6%and 20.7%compared with the untreated hyperlipidemic HepG2 cells.q PCR results showed that highland barley polyphenols could up-regulation the expression of lipid metabolism-related genes such as PPARγand Fabp4. 展开更多
关键词 Highland barley Polyphenols extract Lipid-lowering effect HepG2 cells
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Engineering Strategies for Suppressing the Shuttle Effect in Lithium–Sulfur Batteries 被引量:2
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作者 Jiayi Li Li Gao +7 位作者 Fengying Pan Cheng Gong Limeng Sun Hong Gao Jinqiang Zhang Yufei Zhao Guoxiu Wang Hao Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期187-221,共35页
Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-elect... Lithium–sulfur(Li–S)batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost.Nevertheless,the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical value.Many methods were proposed for inhibiting the shuttle effect of polysulfide,improving corresponding redox kinetics and enhancing the integral performance of Li–S batteries.Here,we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li–S batteries.First,the electrochemical principles/mechanism and origin of the shuttle effect are described in detail.Moreover,the efficient strategies,including boosting the sulfur conversion rate of sulfur,confining sulfur or lithium polysulfides(LPS)within cathode host,confining LPS in the shield layer,and preventing LPS from contacting the anode,will be discussed to suppress the shuttle effect.Then,recent advances in inhibition of shuttle effect in cathode,electrolyte,separator,and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li–S batteries.Finally,we present prospects for inhibition of the LPS shuttle and potential development directions in Li–S batteries. 展开更多
关键词 Shuttle effect Designed strategies Li-S battery Lithium polysulfides
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Experimental study on the effect of water absorption level on rockburst occurrence of sandstone 被引量:1
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作者 Dongqiao Liu Jie Sun +3 位作者 Pengfei He Manchao He Binghao Cao Yuanyuan Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期136-152,共17页
To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and ... To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation. 展开更多
关键词 ROCKBURST Water Prevention effect Crack evolution
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High responsivity photodetectors based on graphene/WSe_(2) heterostructure by photogating effect 被引量:1
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作者 李淑萍 雷挺 +5 位作者 严仲兴 王燕 张黎可 涂华垚 时文华 曾中明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期728-733,共6页
Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material.However, the performance of graphene-based photodetectors is limited by weak absorption efficiency a... Graphene, with its zero-bandgap electronic structure, is a highly promising ultra-broadband light absorbing material.However, the performance of graphene-based photodetectors is limited by weak absorption efficiency and rapid recombination of photoexcited carriers, leading to poor photodetection performance. Here, inspired by the photogating effect, we demonstrated a highly sensitive photodetector based on graphene/WSe_(2) vertical heterostructure where the WSe_(2) layer acts as both the light absorption layer and the localized grating layer. The graphene conductive channel is induced to produce more carriers by capacitive coupling. Due to the strong light absorption and high external quantum efficiency of multilayer WSe_(2), as well as the high carrier mobility of graphene, a high photocurrent is generated in the vertical heterostructure. As a result, the photodetector exhibits ultra-high responsivity of 3.85×10~4A/W and external quantum efficiency of 1.3 × 10~7%.This finding demonstrates that photogating structures can effectively enhance the sensitivity of graphene-based photodetectors and may have great potential applications in future optoelectronic devices. 展开更多
关键词 WSe_(2) HETEROSTRUCTURE PHOTODETECTOR photogating effect
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“Buckets effect”in the kinetics of electrocatalytic reactions 被引量:2
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作者 Haowen Cui Yan-Xia Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期388-396,I0010,共10页
In this study,we systematically investigated the effect of proton concentration on the kinetics of the oxygen reduction reaction(ORR)on Pt(111)in acidic solutions.Experimental results demonstrate a rectangular hyperbo... In this study,we systematically investigated the effect of proton concentration on the kinetics of the oxygen reduction reaction(ORR)on Pt(111)in acidic solutions.Experimental results demonstrate a rectangular hyperbolic relationship,i.e.,the ORR current excluding the effect of other variables increases with proton concentration and then tends to a constant value.We consider that this is caused by the limitation of ORR kinetics by the trace oxygen concentration in the solution,which determines the upper limit of ORR kinetics.A model of effective concentration is further proposed for rectangular hyperbolic relationships:when the reactant concentration is high enough to reach a critical saturation concentration,the effective reactant concentration will become a constant value.This could be due to the limited concentration of a certain reactant for reactions involving more than one reactant or the limited number of active sites available on the catalyst.Our study provides new insights into the kinetics of electrocatalytic reactions,and it is important for the proper evaluation of catalyst activity and the study of structureperformance relationships. 展开更多
关键词 Oxygen reduction reaction KINETICS Zero order Rectangular hyperbolic relationship pH effect
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Complementary and Alternative Medicine: A Review on the Effects of Ginger, Cinnamon and Camellia Sinensis Leaf Tea in Diabetes
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作者 Massud Atta Shadi Jafari Kareen Moore 《Journal of Diabetes Mellitus》 2019年第3期126-136,共11页
Diabetes mellitus is a chronic disease with a multitude of effects on different organ-systems. Its chronic nature makes it a challenging disease for patients to manage. Today, patients have access to many different ty... Diabetes mellitus is a chronic disease with a multitude of effects on different organ-systems. Its chronic nature makes it a challenging disease for patients to manage. Today, patients have access to many different types of conventional therapies for diabetes, each with a different mode of action and side effects. Despite the wide range of therapeutic agents available today, patients seek help from complementary and alternative medicine. The decision to use complementary and alternative medicine by patients stems from some of the harmful side effects of current conventional therapies, as well as their desire to find measures that will help them to manage their disease. Complementary and alternative medicine includes several modalities ranging from dietary components such as vitamins and herbal supplements to mind-body interventions such as yoga, meditation, and massage therapy. Here we review the use of complementary and alternative medicine including Ginger, Cinnamon, and Camellia sinensis leaf tea, and their effects on glycemic indices in diabetes. 展开更多
关键词 DIABETES Mellitus complementary and Alternative Medicine Insulin Hemoglobin A1c Fasting Blood Glucose GINGER CINNAMON Camellia Sinensis ZINGIBER officinale CINNAMOMUM zeylanicum Ceylon CINNAMON CINNAMON CASSIA
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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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Impact of effective stress on permeability for carbonate fractured-vuggy rocks 被引量:1
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作者 Ke Sun Huiqing Liu +5 位作者 Juliana Y.Leung Jing Wang Yabin Feng Renjie Liu Zhijiang Kang Yun Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期942-960,共19页
To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of ef... To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of effective stress on permeability for carbonate fractured-vuggy rocks(CFVR).It shows that the permeability performance curves under different pore and confining pressures(i.e.altered stress conditions)for the fractured core models and the vuggy core models have similar change patterns.The ranges of permeability variation are significantly wider at high pore pressures,indicating that permeability reduction is the most significant during the early stage of development for fractured-vuggy reservoirs.Since each obtained effective stress coefficient for permeability(ESCP)varies with the changes in confining pressure and pore pressure,the effective stresses for permeability of four representative CFVR show obvious nonlinear characteristics,and the variation ranges of ESCP are all between 0 and 1.Meanwhile,a comprehensive ESCP mathematical model considering triple media,including matrix pores,fractures,and dissolved vugs,was proposed.It is proved theoretically that the ESCP of CFVR generally varies between 0 and 1.Additionally,the regression results showed that the power model ranked highest among the four empirical models mainly applied in stress sensitivity characterization,followed by the logarithmic model,exponential model,and binomial model.The concept of“permeability decline rate”was introduced to better evaluate the stress sensitivity performance for CFVR,in which the one-fracture rock is the strongest,followed by the fracture-vug rock and two-horizontalfracture rock;the through-hole rock is the weakest.In general,this study provides a theoretical basis to guide the design of development and adjustment programs for carbonate fractured-vuggy reservoirs. 展开更多
关键词 effective stress PERMEABILITY Carbonate fractured-vuggy rocks Structure characteristics Stress sensitivity
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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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Rockburst criterion and evaluation method for potential rockburst pit depth considering excavation damage effect 被引量:1
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作者 Jinhao Dai Fengqiang Gong Lei Xu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1649-1666,共18页
Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Ta... Excavation-induced disturbances in deep tunnels will lead to deterioration of rock properties and formation of excavation damaged zone(EDZ).This excavation damage effect may affect the potential rockburst pit depth.Taking two diversion tunnels of Jinping II hydropower station for example,the relationship between rockburst pit depth and excavation damage effect is first surveyed.The results indicate that the rockburst pit depth in tunnels with severe damage to rock masses is relatively large.Subsequently,the excavation-induced damage effect is characterized by disturbance factor D based on the Hoek-Brown criterion and wave velocity method.It is found that the EDZ could be further divided into a high-damage zone(HDZ)with D=1 and weak-damage zone(WDZ),and D decays from one to zero linearly.For this,a quantitative evaluation method for potential rockburst pit depth is established by presenting a three-element rockburst criterion considering rock strength,geostress and disturbance factor.The evaluation results obtained by this method match well with actual observations.In addition,the weakening of rock mass strength promotes the formation and expansion of potential rockburst pits.The potential rockburst pit depth is positively correlated with HDZ and WDZ depths,and the HDZ depth has a significant contribution to the potential rockburst pit depth. 展开更多
关键词 Deep tunnel ROCKBURST Rockburst pit Excavation damage effect Hoek-Brown criterion
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Electrode/Electrolyte Interfacial Chemistry Modulated by Chelating Effect for High-Performance Zinc Anode 被引量:1
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作者 Chuanlin Li Guangmeng Qu +2 位作者 Xixi Zhang Chenggang Wang Xijin Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期93-99,共7页
Although Zn metal has been regarded as the most promising anode for aqueous batteries,its practical application is still restricted by side reactions and dendrite growth.Herein,an in-situ solid electrolyte interphase(... Although Zn metal has been regarded as the most promising anode for aqueous batteries,its practical application is still restricted by side reactions and dendrite growth.Herein,an in-situ solid electrolyte interphase(SEI)film formed on the interface of electrode/electrolyte during the plating/stripping of zinc anodes by introducing trace amounts of multidentate ligand sodium diethyldithiocarbamate(DDTC)additive into 1 M ZnSO_(4).The synergistic effect of in-situ solid electrolyte interphase forming and chelate effect endows Zn^(2+)with uniform and rapid interface-diffusion kinetics against dendrite growth and surface side reactions.As a result,the Zn anode in 1 M ZnSO_(4)+DDTC electrolytes displays an ultra-high coulombic efficiency of 99.5%and cycling stability(more than 2000 h),especially at high current density(more than 600 cycles at 40 mA cm^(-2)).Moreover,the Zn//MnO_(2)full cells in the ZnSO_(4)+DDTC electrolyte exhibit outstanding cyclic stability(with 98.6%capacity retention after 2000 cycles at 10 C).This electrode/electrolyte interfacial chemistry modulated strategy provides new insight into enhancing zinc anode stability for high-performance aqueous zinc batteries. 展开更多
关键词 chelating effect in-situ SEI ultra-high current density Zn anodes
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Review on synergistic damage effect of irradiation and corrosion on reactor structural alloys 被引量:1
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作者 Hui Liu Guan-Hong Lei He-Fei Huang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期109-141,共33页
The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fou... The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research focus.This paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt reactors.The competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this paper.Conceptual approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors. 展开更多
关键词 Irradiation and corrosion Synergistic effect Austenitic stainless steels Nickel-based alloys Reactors
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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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