Although body mass index(BMI)is widely used as a simple tool to assess obesity,it has certain limitations and inaccuracies.It is known that visceral adipose tissue is closely related to cardiometabolic risks and all-c...Although body mass index(BMI)is widely used as a simple tool to assess obesity,it has certain limitations and inaccuracies.It is known that visceral adipose tissue is closely related to cardiometabolic risks and all-cause mortality;however,precise measurement methods for visceral fat(magnetic resonance imaging and computed tomography)cannot be widely used.Thus,simple but accurate alternatives are valuable.Studies have shown that waist circumference-to-height ratio(WHtR)might be a superior and more accurate variable in assessing central or visceral adiposity as well as predicting risks of diabetes and other cardiometabolic diseases.Furthermore,WHtR cutoff values can be consistent across different races,age,and genders,making it a universal metric worth promoting and applying.展开更多
We demonstrate that power recycling is feasible by using a semi-transparent stripped Al electrode as interconnecting layer to merge a white organic light-emitting devices(WOLED) and an organic photovoltaic(OPV) cell.T...We demonstrate that power recycling is feasible by using a semi-transparent stripped Al electrode as interconnecting layer to merge a white organic light-emitting devices(WOLED) and an organic photovoltaic(OPV) cell.The device is called a PVOLED.It has a glass / ITO / CuPc / m-MTDATA ∶ V 2 O 5 / NPB / CBP ∶ FIrpic ∶ DCJTB / BPhen / LiF / Al / P3HT∶ PCBM / V 2 O 5 / Al structure.The power recycling efficiency of 10.133% is achieved under the WOLED of PVOLED operated at 9 V and at a brightness of 2 110 cd / m 2,when the conversion efficiency of OPV is 2.3%.We have found that the power recycling efficiency is decreased under high brightness and high applied voltage due to an increase input power of WOLED.High efficiency(18.3 cd / A) and high contrast ratio(9.3) were obtained at the device operated at 2 500 cd / m 2 under an ambient illumination of 24 000 lx.Reasonable white light emission with Commission Internationale De L'Eclairage(CIE) color coordinates of(0.32,0.44) at 20 mA / cm 2 and slight color shift occurred in spite of a high current density of 50 mA / cm 2.The proposed PVOLED is highly promising for use in outdoors display applications.展开更多
Modern human has different body proportion from early hominids and great apes.Comparing with others,in general,modern human adults have relatively long lower limb and heavier body weight.Since the lower limbs provide ...Modern human has different body proportion from early hominids and great apes.Comparing with others,in general,modern human adults have relatively long lower limb and heavier body weight.Since the lower limbs provide support to the whole body and play an important role in walking,it is proposed that the ratio of the lower limb to the whole body for modern human could be beneficial to bipedal walking.This study tried to estimate the muscle parameters of the lower limb in walking for the subjects with various body proportions.Using a simplified musculoskeletal model,some muscle parameters of the lower limb,e.g.muscle force,stress,work and power,were estimated for modern human adult,child,AL 288-1(the fossil specimens of Australopithecus afarensis,3.18 million years old)and apes.The results show that with the body proportion modern human adult spends less muscle work and power in walking than other subjects.The results imply that using the cost of transport(i.e.the muscle work of the lower limb per unit of displacement)as the criteria,the early hominids,if their body proportions were structurally similar to AL 288-1,could evolve towards what modern human adult looks like,in order to save energy during bipedal walking.展开更多
The effect of wall temperature on the characteristics of random combustion of micro organic particles with recirculation was investigated. The effect of recirculating in micro-combustors is noticeable, hence it is nec...The effect of wall temperature on the characteristics of random combustion of micro organic particles with recirculation was investigated. The effect of recirculating in micro-combustors is noticeable, hence it is necessary to present a model to describe the combustion process in these technologies. Recirculation phenomenon is evaluated by entering the exhausted heat from the post flam zone into the preheat zone. In this work, for modeling of random situation at the flame front, the source term in the equation of energy was modeled considering random situation for volatizing of particles in preheat zone. The comparison of obtained results from the proposed model by experimental data regards that the random model has a better agreement with experimental data than non-random model. Also, according to the results obtained by this model, wall temperature affects the amount of heat recirculation directly and higher values of wall temperature will lead to higher amounts of burning velocity and flame temperature.展开更多
Two-factor analysis of variance and redundancy analysis were used to analyze the characte-ristics of soil organic carbon total nitrogen storage in garden land,forestland,grassland,farmland,and bare land in the Dachunh...Two-factor analysis of variance and redundancy analysis were used to analyze the characte-ristics of soil organic carbon total nitrogen storage in garden land,forestland,grassland,farmland,and bare land in the Dachunhe watershed of Jinning District,Kunming City,Yunnan Province,China.The effects of the soil organic carbon,total nitrogen stratification ratio,soil physical and chemical factors on the storage characteristics of organic carbon and total nitrogen of different land-use types were analyzed.The results show that the rates of carbon and nitrogen stratification in soil from 0-20 cm and 40-60 cm of the same land-use types differed are statistically significant(P<0.05).The organic carbon and total nitrogen stratification ratio SR1 of garden land soil are 38.5%and 25.3%,respectively,which are higher than SR^(2).The soil organic carbon and total nitrogen stratification ratio SR^(2) of different land-use types are greater than SR1.There are statistically significant differences in the SR^(2) soil organic carbon and total nitrogen stratification ratios(P<0.05).Soil organic carbon and total nitrogen storage of diffe-rent land-use types gradually decrease with increasing soil depth,with the maximum soil organic carbon and total nitrogen storage in the 0-20 cm soil layer.Soil organic carbon and total nitrogen sto-rage at the same soil depth are significantly different(P<0.05).Soil organic carbon and total nitrogen storage in the garden land are greater than those in the other land-use types.Soil organic carbon and total nitrogen storage in 0-20 cm garden land are 4.96 and 3.19 times than those in bare land,respectively;soil organic carbon and total nitrogen storage are explained by 93.66%and 1.53%in redundancy analysis RDA1 and RDA2,respectively.All physicochemical factors except Available Phosphorus and pH are statistically significance with carbon and nitrogen storage(P<0.05).Soil cationic exchange capacity,Available Phosphorus,C/N ratio,and Moisture Content are positively correlated with organic carbon and total nitrogen storage.In contrast,soil Bulk Density is negatively correlated with organic carbon storage and total nitrogen storage.Available Phosphorus,C/N ratio,and Moisture Content are the main factors promoting soil organic carbon and total nitrogen accumulation.展开更多
The technical feasibility of in situ upgrading technology to develop the enormous oil and gas resource potential in low-maturity shale is widely acknowledged.However,because of the large quantities of energy required ...The technical feasibility of in situ upgrading technology to develop the enormous oil and gas resource potential in low-maturity shale is widely acknowledged.However,because of the large quantities of energy required to heat shale,its economic feasibility is still a matter of debate and has yet to be convincingly demonstrated quantitatively.Based on the energy conservation law,the energy acquisition of oil and gas generation and the energy consumption of organic matter cracking,shale heat-absorption,and surrounding rock heat dissipation during in situ heating were evaluated in this study.The energy consumption ratios for different conditions were determined,and the factors that influence them were analyzed.The results show that the energy consumption ratio increases rapidly with increasing total organic carbon(TOC)content.For oil-prone shales,the TOC content corresponding to an energy consumption ratio of 3 is approximately 4.2%.This indicates that shale with a high TOC content can be expected to reduce the project cost through large-scale operation,making the energy consumption ratio after consideration of the project cost greater than 1.In situ heating and upgrading technology can achieve economic benefits.The main methods for improving the economic feasibility by analyzing factors that influence the energy consumption ratio include the following:(1)exploring technologies that efficiently heat shale but reduce the heat dissipation of surrounding rocks,(2)exploring technologies for efficient transformation of organic matter into oil and gas,i.e.,exploring technologies with catalytic effects,or the capability to reduce in situ heating time,and(3)establishing a horizontal well deployment technology that comprehensively considers the energy consumption ratio,time cost,and engineering cost.展开更多
目的探讨细胞外水分比率(ratio of extracellular water to total body water,ETR)对急性缺血性卒中(acute ischemic stroke,AIS)患者出院结局的影响。方法回顾性分析2018年7月—2024年6月在北京市房山区良乡医院神经内科住院的AIS患者...目的探讨细胞外水分比率(ratio of extracellular water to total body water,ETR)对急性缺血性卒中(acute ischemic stroke,AIS)患者出院结局的影响。方法回顾性分析2018年7月—2024年6月在北京市房山区良乡医院神经内科住院的AIS患者,根据出院结局将患者分为结局良好(mRS评分<3分)组和结局不良(mRS评分≥3分)组。比较两组患者的临床资料和ETR等指标的差异,采用多因素logistic回归分析探讨ETR对患者出院结局的影响,并在不同性别、年龄、BMI、骨骼肌质量指数及入院NIHSS评分亚组中分析ETR对出院结局的影响。结果共纳入AIS患者147例,平均年龄(68.9±12.2)岁,其中男性80例(54.4%),结局良好组107例(72.8%),结局不良组40例(27.2%)。多因素l ogi sti c回归分析显示,ETR升高(OR 2.09,95%CI 1.16~3.76,P=0.014)和ETR≥40.0%(OR 6.24,95%CI 1.33~29.32,P=0.020)是AI S患者出院结局不良的危险因素。亚组分析结果稳健,无明显交互作用(P交互>0.05)。在年龄<71岁、BMI≥24 kg/m2以及入院NIHSS评分≥3分亚组中,ETR对出院结局不良的影响具有显著性。结论ETR是AIS患者出院结局的独立影响因素,高ETR可显著增加出院结局不良的风险。展开更多
基金supported by the“1·3·5 Project”for Disciplines of Excellence,West China Hospital,Sichuan University,China(ZYGD18017)。
文摘Although body mass index(BMI)is widely used as a simple tool to assess obesity,it has certain limitations and inaccuracies.It is known that visceral adipose tissue is closely related to cardiometabolic risks and all-cause mortality;however,precise measurement methods for visceral fat(magnetic resonance imaging and computed tomography)cannot be widely used.Thus,simple but accurate alternatives are valuable.Studies have shown that waist circumference-to-height ratio(WHtR)might be a superior and more accurate variable in assessing central or visceral adiposity as well as predicting risks of diabetes and other cardiometabolic diseases.Furthermore,WHtR cutoff values can be consistent across different races,age,and genders,making it a universal metric worth promoting and applying.
基金Project supported by NSC(98-2221-E-214-003-MY3 and ISU99-01-06)
文摘We demonstrate that power recycling is feasible by using a semi-transparent stripped Al electrode as interconnecting layer to merge a white organic light-emitting devices(WOLED) and an organic photovoltaic(OPV) cell.The device is called a PVOLED.It has a glass / ITO / CuPc / m-MTDATA ∶ V 2 O 5 / NPB / CBP ∶ FIrpic ∶ DCJTB / BPhen / LiF / Al / P3HT∶ PCBM / V 2 O 5 / Al structure.The power recycling efficiency of 10.133% is achieved under the WOLED of PVOLED operated at 9 V and at a brightness of 2 110 cd / m 2,when the conversion efficiency of OPV is 2.3%.We have found that the power recycling efficiency is decreased under high brightness and high applied voltage due to an increase input power of WOLED.High efficiency(18.3 cd / A) and high contrast ratio(9.3) were obtained at the device operated at 2 500 cd / m 2 under an ambient illumination of 24 000 lx.Reasonable white light emission with Commission Internationale De L'Eclairage(CIE) color coordinates of(0.32,0.44) at 20 mA / cm 2 and slight color shift occurred in spite of a high current density of 50 mA / cm 2.The proposed PVOLED is highly promising for use in outdoors display applications.
基金Supported in part by the grants fromthe BiotechnologyBiological Sciences Research Council,the Leverhulme Trustthe Natural Environment Research Council,U.K.
文摘Modern human has different body proportion from early hominids and great apes.Comparing with others,in general,modern human adults have relatively long lower limb and heavier body weight.Since the lower limbs provide support to the whole body and play an important role in walking,it is proposed that the ratio of the lower limb to the whole body for modern human could be beneficial to bipedal walking.This study tried to estimate the muscle parameters of the lower limb in walking for the subjects with various body proportions.Using a simplified musculoskeletal model,some muscle parameters of the lower limb,e.g.muscle force,stress,work and power,were estimated for modern human adult,child,AL 288-1(the fossil specimens of Australopithecus afarensis,3.18 million years old)and apes.The results show that with the body proportion modern human adult spends less muscle work and power in walking than other subjects.The results imply that using the cost of transport(i.e.the muscle work of the lower limb per unit of displacement)as the criteria,the early hominids,if their body proportions were structurally similar to AL 288-1,could evolve towards what modern human adult looks like,in order to save energy during bipedal walking.
文摘The effect of wall temperature on the characteristics of random combustion of micro organic particles with recirculation was investigated. The effect of recirculating in micro-combustors is noticeable, hence it is necessary to present a model to describe the combustion process in these technologies. Recirculation phenomenon is evaluated by entering the exhausted heat from the post flam zone into the preheat zone. In this work, for modeling of random situation at the flame front, the source term in the equation of energy was modeled considering random situation for volatizing of particles in preheat zone. The comparison of obtained results from the proposed model by experimental data regards that the random model has a better agreement with experimental data than non-random model. Also, according to the results obtained by this model, wall temperature affects the amount of heat recirculation directly and higher values of wall temperature will lead to higher amounts of burning velocity and flame temperature.
基金Natural Science Foundation of China(51979134,51779113)Yunnan Provincial Education Department Scientific Research Fund Project(2021J0164)+4 种基金Open Fund Project of Yunnan Provincial Key Laboratory of Highland Wetland Protection and Restoration and Ecological Services(202105AG070002)Provincial Innovation Team on Environmental Pollution and Food Safety and Human Health,Southwest Forestry University(2005AE160017)A Study of Terrestrial Animal Habitats in Li Ziping National Nature Reserve,Sichuan Province(2021ZD0125)The Construction Project of Key Disciplines with Advantages and Characteristics(Ecology)in Yunnan UniversitiesResearch Project of Key Laboratory of Soil Erosion and Control in Yunnan University。
文摘Two-factor analysis of variance and redundancy analysis were used to analyze the characte-ristics of soil organic carbon total nitrogen storage in garden land,forestland,grassland,farmland,and bare land in the Dachunhe watershed of Jinning District,Kunming City,Yunnan Province,China.The effects of the soil organic carbon,total nitrogen stratification ratio,soil physical and chemical factors on the storage characteristics of organic carbon and total nitrogen of different land-use types were analyzed.The results show that the rates of carbon and nitrogen stratification in soil from 0-20 cm and 40-60 cm of the same land-use types differed are statistically significant(P<0.05).The organic carbon and total nitrogen stratification ratio SR1 of garden land soil are 38.5%and 25.3%,respectively,which are higher than SR^(2).The soil organic carbon and total nitrogen stratification ratio SR^(2) of different land-use types are greater than SR1.There are statistically significant differences in the SR^(2) soil organic carbon and total nitrogen stratification ratios(P<0.05).Soil organic carbon and total nitrogen storage of diffe-rent land-use types gradually decrease with increasing soil depth,with the maximum soil organic carbon and total nitrogen storage in the 0-20 cm soil layer.Soil organic carbon and total nitrogen sto-rage at the same soil depth are significantly different(P<0.05).Soil organic carbon and total nitrogen storage in the garden land are greater than those in the other land-use types.Soil organic carbon and total nitrogen storage in 0-20 cm garden land are 4.96 and 3.19 times than those in bare land,respectively;soil organic carbon and total nitrogen storage are explained by 93.66%and 1.53%in redundancy analysis RDA1 and RDA2,respectively.All physicochemical factors except Available Phosphorus and pH are statistically significance with carbon and nitrogen storage(P<0.05).Soil cationic exchange capacity,Available Phosphorus,C/N ratio,and Moisture Content are positively correlated with organic carbon and total nitrogen storage.In contrast,soil Bulk Density is negatively correlated with organic carbon storage and total nitrogen storage.Available Phosphorus,C/N ratio,and Moisture Content are the main factors promoting soil organic carbon and total nitrogen accumulation.
文摘The technical feasibility of in situ upgrading technology to develop the enormous oil and gas resource potential in low-maturity shale is widely acknowledged.However,because of the large quantities of energy required to heat shale,its economic feasibility is still a matter of debate and has yet to be convincingly demonstrated quantitatively.Based on the energy conservation law,the energy acquisition of oil and gas generation and the energy consumption of organic matter cracking,shale heat-absorption,and surrounding rock heat dissipation during in situ heating were evaluated in this study.The energy consumption ratios for different conditions were determined,and the factors that influence them were analyzed.The results show that the energy consumption ratio increases rapidly with increasing total organic carbon(TOC)content.For oil-prone shales,the TOC content corresponding to an energy consumption ratio of 3 is approximately 4.2%.This indicates that shale with a high TOC content can be expected to reduce the project cost through large-scale operation,making the energy consumption ratio after consideration of the project cost greater than 1.In situ heating and upgrading technology can achieve economic benefits.The main methods for improving the economic feasibility by analyzing factors that influence the energy consumption ratio include the following:(1)exploring technologies that efficiently heat shale but reduce the heat dissipation of surrounding rocks,(2)exploring technologies for efficient transformation of organic matter into oil and gas,i.e.,exploring technologies with catalytic effects,or the capability to reduce in situ heating time,and(3)establishing a horizontal well deployment technology that comprehensively considers the energy consumption ratio,time cost,and engineering cost.
文摘目的探讨细胞外水分比率(ratio of extracellular water to total body water,ETR)对急性缺血性卒中(acute ischemic stroke,AIS)患者出院结局的影响。方法回顾性分析2018年7月—2024年6月在北京市房山区良乡医院神经内科住院的AIS患者,根据出院结局将患者分为结局良好(mRS评分<3分)组和结局不良(mRS评分≥3分)组。比较两组患者的临床资料和ETR等指标的差异,采用多因素logistic回归分析探讨ETR对患者出院结局的影响,并在不同性别、年龄、BMI、骨骼肌质量指数及入院NIHSS评分亚组中分析ETR对出院结局的影响。结果共纳入AIS患者147例,平均年龄(68.9±12.2)岁,其中男性80例(54.4%),结局良好组107例(72.8%),结局不良组40例(27.2%)。多因素l ogi sti c回归分析显示,ETR升高(OR 2.09,95%CI 1.16~3.76,P=0.014)和ETR≥40.0%(OR 6.24,95%CI 1.33~29.32,P=0.020)是AI S患者出院结局不良的危险因素。亚组分析结果稳健,无明显交互作用(P交互>0.05)。在年龄<71岁、BMI≥24 kg/m2以及入院NIHSS评分≥3分亚组中,ETR对出院结局不良的影响具有显著性。结论ETR是AIS患者出院结局的独立影响因素,高ETR可显著增加出院结局不良的风险。