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| 1 | The influence of microwave irradiation on rocks for microwaveassisted underground excavation显示文摘Demand is growing for explosive-free rock breakage systems for civil and mining engineering, and spaceindustry applications. This paper highlights the work being undertaken in the Geomechanics Laboratoryof McGill University to make a real application of microwave-assisted mechanical rock breakage to fullfacetunneling machines and drilling. Comprehensive laboratory tests investigated the effect of microwaveradiation on temperature profiles and strength reduction in hard rocks (norite, granite, and basalt)for a range of exposure times and microwave power levels. The heating rate on the surface of the rockspecimens linearly decreased with distance between the sample and the microwave antenna, regardlessof microwave power level and exposure time. Tensile and uniaxial compressive strengths were reducedwith increasing exposure time and power level. Scanning electron micrographs (SEMs) highlightedfracture development in treated basalt. It was concluded that the microwave power level has a strongpositive influence on the amount of heat damage induced to the rock surface. Numerical simulations ofelectric field intensity and wave propagation conducted with COMSOL Multiphysics software generatedtemperature profiles that were in close agreement with experimental results. | Ferri Hassani Pejman M.Nekoovaght Nima Gharib | 2016 | Journal of Rock Mechanics and Geotechnical Engineering2016,8,1: | 69 |
| 2 | Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the Xiangxi Bay显示文摘The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,2008.The hydrodynamic parameters and water quality parameters(e.g.flow velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the Xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 m.The water exchange between the mainstream(the Changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different directions.The water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding process.Meanwhile,the water stability index in the mainstream remained small but it was lowered in the XXB.The main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding process.The grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the process.However,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future. | YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2 & XIAO ShangBin1,3 1 College of Civil & Hydroelectric Engineering,China Three Gorges University,Yichang 443002,China 2 School of Water Resources & Hydropower Engineering,Wuhan University,Wuhan 430072,China 3 Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,China | 2010 | Science China(Technological Sciences)2010,53,4: | 58 |
| 3 | Moment-independent importance measure of basic random variable and its probability density evolution solution显示文摘To analyze the effect of basic variable on failure probability in reliability analysis,a moment-independent importance measure of the basic random variable is proposed,and its properties are analyzed and verified.Based on this work,the importance measure of the basic variable on the failure probability is compared with that on the distribution density of the response.By use of the probability density evolution method,a solution is established to solve two importance measures,which can efficiently avoid the difficulty in solving the importance measures.Some numerical examples and engineering examples are used to demonstrate the proposed importance measure on the failure probability and that on the distribution density of the response.The results show that the proposed importance measure can effectively describe the effect of the basic variable on the failure probability from the distribution density of the basic variable.Additionally,the results show that the established solution on the probability density evolution is efficient for the importance measures. | CUI LiJie,Lü ZhenZhou & ZHAO XinPan School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,China | 2010 | Science China(Technological Sciences)2010,53,4: | 41 |
| 4 | The construction of Markov processes in random environments and the equivalence theorems显示文摘In sec.1, we introduce several basic concepts such as random transition function, p-m process and Markov process in random environment and give some examples to construct a random transition function from a non-homogeneous density function. In sec.2, we construct the Markov process in random enviromment and skew product Markov process by p - m process and investigate the properties of Markov process in random environment and the original process and environment process and skew product process. In sec. 3, we give several equivalence theorems on Markov process in random environment. | HU DiheSchool of Mathematics and Statistics, Wuhan University, Wuhan 430072, China | 2004 | Science China Mathematics2004,47,4: | 27 |
| 5 | The existence and uniqueness of q-process in ran-dom environment显示文摘We introduce some basic concepts such as random (sub-)transition function,q-function in random environment, q-process in random environment and some basic lemmas. For any continuous q-function in random environment, we prove that the q-process in random environment always exists, and that any q-process in random environment satisfies the random Kolmogorov backward equation and the minimal q-process in random environment always exists. When q is a continuous and conservative q-function in random environment, the necessary and sufficient conditions for the uniqueness of q-process in random environment are given. Finally the special cases, homogeneous random transition functions and homogeneous q-processes in random environments are considered. | HU Dihe | 2004 | Science China Mathematics2004,47,5: | 21 |
| 6 | Effect of wide-narrow row arrangement in mechanical pot-seedling transplanting and plant density on yield formation and grain quality of japonica rice显示文摘Mechanical pot-seedling transplanting is an innovatively developed transplanting method that has the potential to replace mechanical carpet-seedling transplanting. However, the initial pot-seedling transplanting machine lacked optimized density spacing and limited yield potential for japonica rice. Therefore, ascertaining the optimized density by wide-narrow rows and the appropriate transplanting method for yield formation and grain quality of japonica rice is of great importance for high-quality rice production. Field experiments were conducted using two japonica rice cultivars Nanjing 9108 and Nanjing 5055 under three transplanting methods in 2016 and 2017: mechanical pot-seedling transplanting with wide-narrow row(K, average row spacing of 30 cm);equidistant row(D, 33 cm×12 cm);and mechanical carpet-seedling transplanting(T, 30 cm×12.4 cm). In addition, five different density treatments were set in K(K1–K5, from 18.62×10~4 to 28.49×10~4 hills ha^(–1)). The results showed that the highest yield was produced by a planting density of 26.88×104 hills ha^(–1) in mechanical pot-seedling transplanting with wide-narrow row with a greater number of total spikelets that resulted from significantly more panicles per area and slightly more grain number per panicle, as compared with equidistant row, and yield among density in wide-narrow row showed a parabolic trend. Compared with mechanical carpet-seedling transplanting, the treatment of the highest yield increased yield significantly, which was mainly attributed to the larger sink size with improved filled-grain percentage and grain weight, higher harvest index, and increased total dry matter accumulation, especially the larger amount accumulated from heading stage to maturity stage. With the density in wide-narrow row decreasing, processing quality, appearance quality, and nutrition quality were all improved, whereas amylose content and the taste value were decreased. Compared with mechanical carpet-seedling transplanting, mechanical pot-seedling transplanting improved processing quality and nutrition quality, but decreased amylose content and deteriorated appearance quality. These results suggested that mechanical pot-seedling transplanting with wide-narrow row coupling produced a suitable planting density of 26.88×10~4 hills ha^(–1) and may be an alternative approach to improving grain yield and quality for japonica rice. | HU Qun JIANG Wei-qin QIU Shi XING Zhi-peng HU Ya-jie GUO Bao-wei LIU Guo-dong GAO Hui ZHANG Hong-cheng WEI Hai-yan | 2020 | Journal of Integrative Agriculture2020,19,5: | 19 |
| 7 | Hand bone mass in rheumatoid arthritis:A review of the literature显示文摘Rheumatoid arthritis(RA) is a common chronic inflammatory disease and periarticular osteoporosis or osteopenia of the inflamed hand joints is an early feature of RA Quantitative measurement of hand bone loss may be an outcome measure for the detection of joint destruction and disease progression in early RA. This systematic review examines the published literature reporting hand bone mass in patients with RA, particularly those using the dual X-ray absorptiometry(DXA) methods The majority of the studies reported that hand bone loss is associated with disease activity, functional statusand radiological progression in early RA. Quantitative measurement of hand bone mineral density by DXA may be a useful and practical outcome measure in RA and may be predictive for radiographic progression or functional status in patients with early RA. | Gamze Kilic Salih Ozgocmen | 2015 | World Journal of Orthopedics2015,6,1: | 18 |
| 8 | Effect of lipid on proliferation and activation of rat hepatic stellate cells(Ⅰ)显示文摘INTRODUCTIONDespitetheearlycontroversyovertheprimarycelularsourceofextracelularmatrixproteinsinliverfibrosis,compelinginvitro... | LU Lun Gen, ZENG Min De, LI Ji Qiang, HUA Jing, FAN Jian Gao, FAN Zhu Ping and QIU De Kai | 1998 | World Journal of Gastroenterology1998,4,6: | 18 |
| 9 | Effect of NF-κB inhibitor PDTC on VEGF and endostatin expression of mice with Lewis lung cancer显示文摘Objective:To investigate the effects of NF-κB inhibitor pyrrolidine dithiocarbamate hydrochloride(PDTC) on vascular endothelial growth factor(VEGF) and endostatin expression in mice with Lewis lung cance;and its mechanism.Methods:Mice survival rate and anti-tumor effects were observed in different concentrations of NF-κB inhibitor PDTC after the Lewis lung cancer mice model was established.VEGF and endostatin expressions were detected by immunohistochemical assay.Results:Lewis lung cancer was be inhibited by 0.5 mg/kg.1.5 mg/kg and 3.0 mg/kg of NF-κB inhibitor PDTC(P<0.05).Microvessel density(MVD) in 0.5 mg/kg.1.5 mg/kg and 3.0 mg/kg NF-κB inhibitor PDTC groups were significantly lower than the control group(P<0.05).Immunohistochemical assay results showed that VEGF and endostatin expressions in the 0.5 mg/kg.1.5 mg/kg and 3.0 mg/kg NF-κB inhibitor PDTC groups were significantly lower than the control group(P<0.05).Western blot results also showed that NF-κB inhibitor PDTC could inhibit VEGF and endostatin expressions in tumor tissues.Conclusions:NF-κB inhibitor PDTC can inhibit tumor formation and reduce tumor angiogenesis in mice with Lewis lung cancer;and its mechanism maybe associated to VEGF and endostatin down-regulation. | Ping Gao Ya-Jie Gao Hong-Lu Liang | 2015 | Asian Pacific Journal of Tropical Medicine2015,8,3: | 18 |
| 10 | Carbon budgets of three temperate forest ecosystems in Dongling Mt.,Beijing,China显示文摘There is a general agreement that forest ecosystems in the Northern Hemisphere function as signifi-cant sinks for atmospheric CO2; however, their magnitude and distribution remain large uncertainties. In this paper, we report the carbon (C) stock and its change of vegetation, forest floor detritus, and mineral soil, annual net biomass increment and litterfall production, and respiration of vegetation and soils between 1992 to 1994, for three temperate forest ecosystems, birch (Betula platyphylla) forest, oak (Quercus liaotungensis) forest and pine (Pinus tabulaeformis) plantation in Mt. Dongling, Beijing, China. We then evaluate the C budgets of these forest ecosystems. Our results indicated that total C density (organic C per hectare) of these forests ranged from 250 to 300 t C ha-1, of which 35―54 t C ha-1 from vegetation biomass C and 209―244 t C ha-1 from soil organic C (1 m depth, including forest floor detritus). Biomass C of all three forests showed a net increase, with 1.33―3.55 t C ha-1 a-1 during the study period. Litterfall production, vegetation autotrophic respiration, and soil heterotrophic respira-tion were estimated at 1.63―2.34, 2.19―6.93, and 1.81―3.49 t C ha-1 a-1, respectively. Ecosystem gross primary production fluctuated between 5.39 and 12.82 t C ha-1 a-1, about half of which (46%―59%, 3.20―5.89 t C ha-1 a-1) was converted to net primary production. Our results suggested that pine forest fixed C of 4.08 t ha-1 a-1, whereas secondary forests (birch and oak forest) were nearly in balance in CO2 exchange between the atmosphere and ecosystems. | FANG JingYun LIU GuoHua ZHU Biao WANG XiaoKe LIU ShaoHui | 2007 | Science China Earth Sciences2007,50,1: | 17 |
| 11 | Silymarin in non alcoholic fatty liver disease显示文摘AIM: This study was undertaken to evaluate the hepatic effects of silybum marianum on non alcoholic fatty liver disease (NAFLD). METHODS: In 72 patients affected by NAFLD, main metabolic, hepatic and anti-inflammatory parameters were assayed after 3 mo of a restricted diet and before silymarin treatment (twice a day orally). The brightness of liver echography texture (hepatorenal ratio brightness) was also defined at same time. These evaluations were repeated after 6 mo of treatment. RESULTS: Serum levels of some metabolic and anti-inflammatory data nonsignificantly lowered after 6 mo of silymarin. On the contrary, Steato test, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transpeptidase were significantly (P < 0.001) reduced. Instead, the AST/ALT ratio unchanged. Finally, the hepatorenal brightness ratio, as an index of hepatic steatosis, significantly (P < 0.05) dropped. CONCLUSION: The obtained results indicate that silymarin appears to be effective to reduce the biochemical, inflammatory and ultrasonic indices of hepatic steatosis. Some parameters indicative of early stage of atherosclerosis were also lowered. | Fulvio Cacciapuoti Anna Scognamiglio Rossella Palumbo Raffaele Forte Federico Cacciapuoti | 2013 | World Journal of Hepatology2013,5,3: | 17 |
| 12 | Nestin:A novel angiogenesis marker and possible target for tumor angiogenesis显示文摘Abnormal vasculature,termed tumor vessels,is a hallmark of solid tumors.The degree of angiogenesis is associated with tumor aggressiveness and clinical outcome.Therefore,exact quantification of tumor vessels is useful to evaluate prognosis.Furthermore,selective detection of newly formed tumor vessels within cancer tissues using specific markers raises the possibility of molecular targeted therapy via the inhibition of tumor angiogenesis.Nestin,an intermediate filament protein,is reportedly expressed in repair processes,various neoplasms,and proliferating vascular endothelial cells.Nestin expression is detected in endothelial cells of embryonic capillaries,capillaries of the corpus luteum,which replenishes itself by angiogenesis,and proliferating endothelial progenitor cells,but not in mature endothelial cells.Therefore,expression of nestin is relatively limited to proliferating vascular endothelial cells and endothelial progenitor cells.Nestin expression is also reported in blood vessels within glioblastoma,prostate cancer,colorectal cancer,and pancreatic cancer,and its expression is more specific for newly formed blood vessels than other endothelial cell markers.Nestin-positive blood vessels form smaller vessels with high proliferation activity in tumors.Knockdown of nestin in vascular endothelial cells suppresses endothelial cell growth and tumor formation ability of pancreatic cancers in vivo.Using nestin to more accurately evaluate microvessel density in cancer specimens may be a novel prognostic indicator.Furthermore,nestin-targeted therapy may suppress tumor proliferation via inhibition of angiogenesis in numerous malignancies,including pancreatic cancer.In this review article,we focus on nestin as a novel angiogenesis marker and possible therapeutic target via inhibition of tumor angiogenesis. | Yoko Matsuda Masahito Hagio Toshiyuki Ishiwata | 2013 | World Journal of Gastroenterology2013,19,1: | 16 |
| 13 | Study of density field measurement based on NPLS technique in supersonic flow显示文摘Due to the influence of shock wave and turbulence, supersonic density field exhibits strongly inhomogeneous and unsteady characteristics. Applying traditional density field measurement techniques to supersonic flows yields three problems: low spatiotemporal resolution, limitation of measuring 3D density field, and low signal to noise ratio (SNR). A new method based on Nano-based Planar Laser Scattering (NPLS) technique is proposed in this paper to measure supersonic density field. This method measures planar transient density field in 3D supersonic flow by calibrating the relationship between density and concentration of tracer particles, which would display the density fluctuation due to the influence of shock waves and vortexes. The application of this new method to density field measurement of supersonic optical bow cap is introduced in this paper, and the results reveal shock wave, turbulent boundary layer in the flow with the spatial resolution of 93.2 μm/pixel. By analyzing the results at interval of 5 μs, temporal evolution of density field can be observed. | TIAN LiFeng YI ShiHe ZHAO YuXin HE Lin CHENG ZhongYu | 2009 | Science China(Physics,Mechanics & Astronomy)2009,52,9: | 15 |
| 14 | Risk factors for osteoporosis in inflammatory bowel disease patients显示文摘Inflammatory bowel disease(IBD) patients exhibit higher risk for bone loss than the general population. The chronic inflammation causes a reduction in bone mineral density(BMD), which leads to osteopenia and osteoporosis. This article reviewed each risk factor for osteoporosis in IBD patients. Inflammation is one of the factors that contribute to osteoporosis in IBD patients, and the main system that is involved in bone loss is likely RANK/RANKL/osteoprotegerin. Smoking is a risk factor for bone loss and fractures, and many mechanisms have been proposed to explain this loss. Body composition also interferes in bone metabolism and increasing muscle mass may positively affect BMD. IBD patients frequently use corticosteroids, which stimulates osteoclastogenesis. IBD patients are also associated with vitamin D deficiency, which contributes to bone loss. However, infliximab therapy is associated with improvements in bone metabolism, but it is not clear whether the effects are because of inflammation improvement or infliximab use. Ulcerative colitis patients with proctocolectomy and ileal pouches and Crohn's disease patients with ostomy are also at risk for bone loss, and these patients should be closely monitored. | Carla Andrade Lima Andre Castro Lyra Raquel Rocha Genoile Oliveira Santana | 2015 | World Journal of Gastrointestinal Pathophysiology2015,6,4: | 15 |
| 15 | Molecular dynamics simulations on the structures and properties of ε-CL-20-based PBXs ——Primary theoretical studies on HEDM formulation design显示文摘Five polymer bonded explosives (PBXs) with the base explosive ε-CL-20 (hexanitrohexaazaisowurtzi- tane), the most important high energy density compound (HEDC), and five polymer binders (Estane 5703, GAP, HTPB, PEG, and F2314) were constructed. Molecular dynamics (MD) method was employed to investigate their binding energies (Ebind), compatibility, safety, mechanical properties, and energetic properties. The information and rules were reported for choosing better binders and guiding formula- tion design of high energy density material (HEDM). According to the calculated binding energies, the ordering of compatibility and stability of the five PBXs was predicted as ε-CL-20/PEG > ε-CL-20/ Estane5703 ≈ε-CL-20/GAP > ε-CL-20/HTPB > ε-CL-20/F2314. By pair correlation function g(r) analyses, hydrogen bonds and vdw are found to be the main interactions between the two components. The elasticity and isotropy of PBXs based ε-CL-20 can be obviously improved more than pure ε-CL-20 crystal. It is not by changing the molecular structures of ε-CL-20 for each binder to affect the sensitivity. The safety and energetic properties of these PBXs are mainly influenced by the thermal capability (C°p) and density (ρ) of binders, respectively. | XU XiaoJuan1,2, XIAO JiJun1, HUANG Hui3, LI JinShan3 & XIAO HeMing1 1 Department of Chemistry, Nanjing University of Science and Technology, Nanjing 210094, China 2 Department of Chemistry, Yancheng Teacher’s College, Yancheng 224002, China 3 Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621900, China | 2007 | Science China Chemistry2007,50,6: | 15 |
| 16 | Association of serum lipid levels with diabetic retinopathy显示文摘AIM: To assess the association between serum lipids and diabetic retinopathy (DR). · METHODS: Sixty -one diabetic patients without retinopathy (NDR), 55 diabetic patients with non - proliferative retinopathy (NPDR) and 75 diabetic patients with proliferative retinopathy (PDR) according to ETDRS grading scale were enrolled in this study. Total cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), very low density lipoprotein (VLDL) and triglyceride values were compared between the groups. ·RESULTS: The groups were well-balanced in terms of age and gender (P =0.071, P =0.265 respectively). The mean HbA1c values were significantly lower in NDR group than the NPDR and PDR groups(P =0.004, P =0.009 respectively). Mean total cholesterol, triglyceride, LDL, HDL and VLDL levels were not significantly different between the groups (P =0.693, P =0.774, P =0.644, P = 0.910 and P =0.967 respectively, one way ANOVA). Mean total cholesterol, triglyceride, LDL, HDL and VLDL levels were not significantly different between the patients with ME and patients without ME(P =0.622, P =0.113, P =0.955, P =0.735 and P =0.490 respectively, t -test). The mean blood glucose significantly correlated with total cholesterol (r =0.173, P =0.017) and LDL (r =0.190, P = 0.008). The mean HbA1c significantly correlated with total cholesterol (r =0.158, P =0.030) and triglyceride (r =0.148, P =0.042). ·CONCLUSION: Serum lipid levels were not significantly associated with the severity of DR or existence of ME despite the significant correlation between the mean blood glucose, HbA1c and total cholesterol. | Ebru Nevin Cetin Yunus Bulgu Seyfullah Ozdemir Senay Topsakal Fulya Akln Hulya Aybek Cem Ylldlrlm | 2013 | International Journal of Ophthalmology(English edition)2013,6,3: | 14 |
| 17 | An enriched environment promotes synaptic plasticity and cognitive recovery after permanent middle cerebral artery occlusion in mice显示文摘Cerebral ischemia activates an endogenous repair program that induces plastic changes in neurons. In this study, we investigated the effects of environmental enrichment on spatial learning and memory as well as on synaptic remodeling in a mouse model of chronic cerebral ischemia, produced by subjecting adult male C57 BL/6 mice to permanent left middle cerebral artery occlusion. Three days postoperatively, mice were randomly assigned to the environmental enrichment and standard housing groups. Mice in the standard housing group were housed and fed a standard diet. Mice in the environmental enrichment group were housed in a cage with various toys and fed a standard diet. Then, 28 days postoperatively, spatial learning and memory were tested using the Morris water maze. The expression levels of growth-associated protein 43, synaptophysin and postsynaptic density protein 95 in the hippocampus were analyzed by western blot assay. The number of synapses was evaluated by electron microscopy. In the water maze test, mice in the environmental enrichment group had a shorter escape latency, traveled markedly longer distances, spent more time in the correct quadrant(northeast zone), and had a higher frequency of crossings compared with the standard housing group. The expression levels of growth-associated protein 43, synaptophysin and postsynaptic density protein 95 were substantially upregulated in the hippocampus in the environmental enrichment group compared with the standard housing group. Furthermore, electron microscopy revealed that environmental enrichment increased the number of synapses in the hippocampal CA1 region. Collectively, these findings suggest that environmental enrichment ameliorates the spatial learning and memory impairment induced by permanent middle cerebral artery occlusion. Environmental enrichment in mice with cerebral ischemia likely promotes cognitive recovery by inducing plastic changes in synapses. | Chuan-Jie Wang Yi Wu Qun Zhang Ke-Wei Yu Yu-Yang Wang | 2019 | Neural Regeneration Research2019,14,3: | 14 |
| 18 | Efficacy of intravenous zoledronic acid in the prevention and treatment of osteoporosis:A meta-analysis显示文摘Objective:To compare the eflect of zoledronic acid in treatment and prevention of osteoporosis with placebo.Methods:Random control trials regarding zoleilroiiic acid in treatment of osteoporosis were retrieved by selecting Medline.EMbase and Pubmed databases till April 2012. The RevMan software was used for all of the statistical analysis.Results:A total of 9 trials were included in this meta-analysis.The pooled effect shewed that zoledronic acid could increase the bone mineral density by 2.98 times compared with placebo,and reduce the rate of fracture in patients by 32%.The results should the zoledronic acid intervention had significantly less serious adverse events than controls,and the odds ratio was 0.81(0.76-0.87).The longer term intervention, more than 12 months intervention,could gain a better prevention effect for osteoporosis(OR,95% CI for RMD was 3.35.2.77-3.92:for fracture was 0.67.0.54-0.82).Conclusions:This present study shows that zoledronic acid could be effective approach in the prevention of osteoporosis,and could increase the bone mineral density and reduce the risk ol facture. | Jun Zhang Ran Wang Yi-Lei Zhao Xiao-Hui Sun Hong-Xing Zhao Tan Lu De-Cai Chen Hai-Bin Xu | 2012 | Asian Pacific Journal of Tropical Medicine2012,5,9: | 14 |
| 19 | Systematic review of soy isoflavone supplements on osteoporosis in women显示文摘Objective:To clarify the effect of soy isoflavones on prevention of osteoporosis,and the effective dosage of soy isoflavones and its duration.Methods:Random control trials that investigated the association of soy isoflavones and osteoporosis were included in the meta-analysis by researching MEDLINE,EMBASE and the Chinese Biomedical Database up to October 2011.The RevMan software was used for all of the statistical analysis.Results:The present meta-analysis found that soy isoflavones significantly increased the bone mineral density by 54%and decreased the bone resorption marker urinary deoxypyridinoline(DPD) by 23%compared to baseline in women. Using random effects model,the effect of isoflavones on bone mineral density(BMD) regarding menopausal status and isoflavone dose revealed higher weighted mean difference changes were found in postmenopausal women and isoflavone dose above 75 mg/d.Subgroup analysis of trials with menopausal status,supplement type,isoflavone dose and intervention duration that used soy isoflavone extracts resulted in significant diflerent overall effect of DPD using by random effects model.Sensitivity analysis indicated that the effect of soy isoflavones on BMD and DPD was robust.Conclusions:The present meta-analysis reveals that soy isoflavone supplements significandy increase bone mineral density and decrease the bone,resorption marker urinary DPD.It shows no significant effect on bone formation markers serum bone alkaline phosphatase. The significant effect of soy isoflavones on BMD and urinary DPD is relative to menopausal status, supplement type,isoflavone dose and intervention duration. | Pan Wei Ming Liu Yan Chen De-Cai Chen | 2012 | Asian Pacific Journal of Tropical Medicine2012,5,3: | 13 |
| 20 | 中国城市碳排放强度的空间溢出效应及驱动因素探究(英文)显示文摘In this study, we adopt kernel density estimation, spatial autocorrelation, spatial Markov chain, and panel quantile regression methods to analyze spatial spillover effects and driving factors of carbon emission intensity in 283 Chinese cities from 1992 to 2013. The following results were obtained.(1) Nuclear density estimation shows that the overall average carbon intensity of cities in China has decreased, with differences gradually narrowing.(2) The spatial autocorrelation Moran's I index indicates significant spatial agglomeration of carbon emission intensity is gradually increasing; however, differences between regions have remained stable.(3) Spatial Markov chain analysis shows a Matthew effect in China's urban carbon emission intensity. In addition, low-intensity and high-intensity cities characteristically maintain their initial state during the transition period. Furthermore, there is a clear 'Spatial Spillover' effect in urban carbon emission intensity and there is heterogeneity in the spillover effect in different regional contexts; that is, if a city is near a city with low carbon emission intensity, the carbon emission intensity of the first city has a higher probability of upward transfer, and vice versa.(4) Panel quantile results indicate that in cities with low carbon emission intensity, economic growth, technological progress, and appropriate population density play an important role in reducing emissions. In addition, foreign investment intensity and traffic emissions are the main factors that increase carbon emission intensity. In cities with high carbon intensity, population density is an important emission reduction factor, and technological progress has no significant effect. In contrast, industrial emissions, extensive capital investment, and urban land expansion are the main factors driving the increase in carbon intensity. | 王少剑 黄永源 周钰荃 | 2019 | Journal of Geographical Sciences2019,29,2: | 13 |