The time-of-use(TOU)strategy can effectively improve the energy consumption mode of customers,reduce the peak-valley difference of load curve,and optimize the allocation of energy resources.This study presents an Opti...The time-of-use(TOU)strategy can effectively improve the energy consumption mode of customers,reduce the peak-valley difference of load curve,and optimize the allocation of energy resources.This study presents an Optimal guidance mechanism of the flexible load based on strategies of direct load control and time-of-use.First,this study proposes a period partitioning model,which is based on a moving boundary technique with constraint factors,and the Dunn Validity Index(DVI)is used as the objective to solve the period partitioning.Second,a control strategy for the curtailable flexible load is investigated,and a TOU strategy is utilized for further modifying load curve.Third,a price demand response strategy for adjusting transferable load is proposed in this paper.Finally,through the case study analysis of typical daily flexible load curve,the efficiency and correctness of the proposed method and model are validated and proved.展开更多
The resonant excitation is used to generate photo-excited carriers in quantum wells to observe the process of the carriers transportation by comparing the photoluminescence results between quantum wells with and witho...The resonant excitation is used to generate photo-excited carriers in quantum wells to observe the process of the carriers transportation by comparing the photoluminescence results between quantum wells with and without a p-n junction. It is observed directly in experiment that most of the photo-excited carriers in quantum wells with a p-n junction escape from quantum wells and form photoeurrent rather than relax to the ground state of the quantum wells. The photo absorption coei^cient of multiple quantum wells is also enhanced by a p-n junction. The results pave a novel way for solar cells and photodetectors making use of low-dimensional structure.展开更多
Dear Editor, In 2011, Son et al. (2011) reported that the forced expression of selected transcription factors is sufficient to convert mouse and human fibroblasts into induced motor neurons (iMNs). The authors use...Dear Editor, In 2011, Son et al. (2011) reported that the forced expression of selected transcription factors is sufficient to convert mouse and human fibroblasts into induced motor neurons (iMNs). The authors used three factors (Ascll, Brn2, and Mytll) to convert fibroblasts into neuronal-like ceils. After confirming that the cells had neuronal morphology, but with absence of motor neuron markers, eight candidate transcription factors were added, which participate in various stages of motor neuron specification. As expected, a significant number of motor cells emerged with known characteristics of cultured embryonic motor neurons.展开更多
BACKGROUND Statins have an important and well-established role in the prevention of atherosclerotic cardiovascular disease(ASCVD).However,several studies have reported widespread underuse of statins in various practic...BACKGROUND Statins have an important and well-established role in the prevention of atherosclerotic cardiovascular disease(ASCVD).However,several studies have reported widespread underuse of statins in various practice settings and populations.Review of relevant literature reveals opportunities for improvement in the implementation of guideline-directed statin therapy(GDST).AIM To examine the impact of cardiologist intervention on the use of GDST in the ambulatory setting.METHODS Patients with at least one encounter at the adult Internal Medicine Clinic(IMC)and/or Cardiology Clinic(CC),who had an available serum cholesterol test performed,were evaluated.The 2 comparison groups were defined as:(1)Patients only seen by IMC;and(2)Patients seen by both IMC and CC.Patients were excluded if variables needed for calculation of ASCVD risk scores were lacking,and if demographic information lacked guideline-directed treatment recommendations.Data were analyzed using student t-tests or χ^2,as appropriate.Analysis of Variance was used to compare rates of adherence to GDST.RESULTS A total of 268 patients met the inclusion criteria for this study;211 in the IMC group and 57 in the IMC-CC group.Overall,56%of patients were female,mean age 56 years(±10.65,SD),22%Black or African American,56%Hispanic/Latino,14%had clinical ASCVD,13%current smokers,66%diabetic and 63%hypertensive.Statin use was observed in 55%(n=147/268)of the entire patient cohort.In the IMC-CC group,73.6%(n=42/57)of patients were prescribed statin therapy compared to 50.7%(n=107/211)of patients in the IMC group(P=0.002).In terms of appropriate statin use based on guidelines,there was no statistical difference between groups[IMC-CC group 61.4%(n=35/57)vs IMC group,55.5%(n=117/211),P=0.421].Patients in the IMC-CC group were older,had more cardiac risk factors and had higher proportions of non-white patients compared to the IMC group(P<0.02,all).CONCLUSION Although overall use of GDST was suboptimal,there was no statistical difference in appropriate statin use based on guidelines between groups managed by general internists alone or co-managed with a cardiologist.These findings highlight the need to design and implement strategies to improve adherence rates to GDST across all specialties.展开更多
Labor scarcity requires double-season rice to be planted by direct seeding as an alternative to transplanting. Only ultrashort-duration varieties can be used in direct-seeded, double-season rice(DSD) in central China ...Labor scarcity requires double-season rice to be planted by direct seeding as an alternative to transplanting. Only ultrashort-duration varieties can be used in direct-seeded, double-season rice(DSD) in central China where thermal time is limited. Whether ultrashort-duration varieties grown in DSD can be as productive and efficient in nitrogen(N) use as transplanted double-season rice(TPD) remains unclear. Field experiments were conducted in Hubei province, central China with two establishment methods(DSD,TPD) and three N rates in the early and late seasons of 2017 and 2018. Nitrogen treatments included zero-N control(N0), total N rate of 60 kg N ha;with equal splits at basal, midtillering, and panicle initiation(N1), and weekly N application at 15 kg ha;from seeding/transplanting to heading(N2). Both early-and late-season rice under DSD matured within 95 days, on average 9 days shorter than rice under TPD. The grain yield of DSD was comparable to or higher than that of TDP in both seasons, although the daily yield was significantly higher under DSD than under TDP. Before heading, DSD had higher leaf area,stem number, intercepted radiation, and radiation use efficiency than TPD, which compensated for the negative effect of short growth duration on biomass production. Total dry weight and harvest index under DSD were comparable to or higher than those under TDP. In general, the recovery efficiency of fertilizer-N under DSD was higher than that under TPD, but the reverse was true for physiological N use efficiency. Thus, there was no significant difference in agronomic N use efficiency between DSD and TPD. These results suggested that DSD with ultrashort-duration varieties is a promising alternative to TPD in central China for maintaining high grain yield and N fertilizer use efficiency with less labor input.展开更多
We report the results of protein folding (219M, C34, N36, 2KES, 2KHK) by the method of accelerated molecular dynamics (aMD) at room temperature with the implicit solvent model. Starting from the linear structures,...We report the results of protein folding (219M, C34, N36, 2KES, 2KHK) by the method of accelerated molecular dynamics (aMD) at room temperature with the implicit solvent model. Starting from the linear structures, these proteins successfully fold to the native structure in a lO0-ns aMD simulation. In contrast, they are failed under the traditional MD simulation in the same simulation time. Then we find that the lowest root mean square deviations of helix structures from the native structures are 0.36 A, 0.63 A, 0.52 A, 1.1 A and 0.78 A. What is more, native contacts, cluster and free energy analyses show that the results of the aMD method are in accordance with the experiment very well. All analyses show that the aMD can accelerate the simulation process, thus we may apply it to the field of computer aided drug designs.展开更多
All synthetic and natural estrogen receptor agonists, in- cluding the most potent physiological molecule estrogen or estradiol (E2), work typically via activation of nuclear estrogen receptor alpha (ERα) and estr...All synthetic and natural estrogen receptor agonists, in- cluding the most potent physiological molecule estrogen or estradiol (E2), work typically via activation of nuclear estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). Both ERα and ERβ modulate the expression of a variety of genes in the cells. Neurons and glial cells express ERa and ERβ. Many studies so far from our and other laboratories have firmly established the mode of actions that ERα and ERβ agonists are very promising anti-inflammatory and neuroprotective agents in the treatment of neurodegenera- rive diseases and injuries including spinal cord injury (SCI) (Chakrabarti et al., 2014a).展开更多
Using the evaluation indicator system for arable land fertility in Suiping County,this paper analyzes some factors influencing agricultural production,such as physical and chemical properties of soil,site conditions,s...Using the evaluation indicator system for arable land fertility in Suiping County,this paper analyzes some factors influencing agricultural production,such as physical and chemical properties of soil,site conditions,soil management,and soil nutrients concerning various types of low-yielding fields in the county. In accordance with the dominant soil constraint factors and main direction of improvement,the lowyielding fields in the county are divided into four types: irrigation improvement type,waterlogging drainage type,barren soil fertilization and barrier layer type. Finally this paper offers specific guidance on the construction of arable land.展开更多
The optical frequency comb has been widely used in precision measurement. In this study, a multi-peak fitting approach is first proposed to fit the two-photon transition spectrum which overlaps with the neighboring tr...The optical frequency comb has been widely used in precision measurement. In this study, a multi-peak fitting approach is first proposed to fit the two-photon transition spectrum which overlaps with the neighboring transition in Rb-87. The multi-peak fitting approach is used to eliminate the frequency shift affected by the neighboring transition. With locking the carrier envelope offset frequency at 1/4 repetition frequency, the transition frequency is measured to be 770569132739.9 +/- 5.8 kHz, which agrees well with the previous result recommended by Comite International des Poids et Mesures.展开更多
Conceptually,rural complex is actually a comprehensive sustainable development model for new agricultural and rural areas across industries and functions.From the perspective of rural complex,combined with the actual ...Conceptually,rural complex is actually a comprehensive sustainable development model for new agricultural and rural areas across industries and functions.From the perspective of rural complex,combined with the actual case of Idyllic Orient in Yangshan,Wuxi,the first rural complex in China,this paper analyzes the current benefits of relevant projects.Considering the basic situation of Luodeli Village in Luquan County,Yunnan Province,the direction,development model and spatial allocation of land use are initially determined.Finally,the overall development path is proposed for Luodeli Village in Luquan County,in order to provide some ideas for its next development.展开更多
Strontium has four naturally occurring stable isotopes,84Sr,86Sr,87Sr,and 88Sr,with abundances of 0.56,9.87,approximately 7.04,and 82.53 atomic %,respectively.The 87Sr/86Sr isotope ratio is variable due to the additio...Strontium has four naturally occurring stable isotopes,84Sr,86Sr,87Sr,and 88Sr,with abundances of 0.56,9.87,approximately 7.04,and 82.53 atomic %,respectively.The 87Sr/86Sr isotope ratio is variable due to the addition of radiogenic 87Sr produced by the beta decay of 87Rb with a half-life of 4.88 ± 0.05 Ga.Thus,展开更多
This paper reports a new method of titration for very weak acids and bases using the appearance of incisions on oscillopolarogram to indicate the end-point.This method has the advantages of rapidity,simplicity,no indi...This paper reports a new method of titration for very weak acids and bases using the appearance of incisions on oscillopolarogram to indicate the end-point.This method has the advantages of rapidity,simplicity,no indicator needed as well as good precision.展开更多
The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the per...The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the perception and importance attributed to the ecosystem services (ESs) provided by riparian corridors in 368 households across 70 villages located in a buffer zone of 5 km of servitude around the permanent rivers of the Upper Oueme watershed in Benin. We found that local communities easily reported provisioning and cultural ESs than regulating and supporting ones, indicating their misunderstanding of the main role of riparian corridor. Moreover, the supply of cropping areas was perceived as the most important ES. Educated respondents and high-income households had more knowledge of regulating ESs and supporting ESs, respectively. Overall, the highly perceived importance of the provision of cropping areas indicates a potential risk of agricultural encroachment of riparian corridors. We suggest the consideration of the current local perception of riparian corridor’s role in designing a sound environmental education aiming at the change of local population’s perception. This perception shift will promote a sustainable management of the riparian corridors.展开更多
Beijing has been experiencing a severe shortage of water. At present serious wastes of water resources result from the unreasonable structure of water uses in various industries sectors. The current conditions of t...Beijing has been experiencing a severe shortage of water. At present serious wastes of water resources result from the unreasonable structure of water uses in various industries sectors. The current conditions of the municipal water use structure and its changes in the industrial sectors were analysed and discussed in terms of the indicators, such as direct water use coefficient, complete water use coefficient, water use multiplier and water reuse rate, by taking a year of 1990s as the base year. Some response strategies for water conservation have been studied and the corresponding recommendations were put forward. All of these have provided a basis for coordinating the relationship between aquatic environment and economic growth in this city, establishing a system for rational utilization of water resources, and promoting the implementation of a strategy for sustainable development.展开更多
Different irrigation schemes have different effects on water consumption in rice production.However,few studies have been conducted on the water consumption processes between dry direct seeding rice and transplanting ...Different irrigation schemes have different effects on water consumption in rice production.However,few studies have been conducted on the water consumption processes between dry direct seeding rice and transplanting rice under different irrigation schemes.Water consumption process,water use efficiency and correlation effect of water consumption on yield under different planting models in rice production were investigated in northeast China in 2018.Seven treatments were implemented:drip irrigation dry direct seeding rice(DDSR),wet irrigation dry direct seeding rice(WDSR),flooded irrigation dry direct seeding rice(FDSR),transplanting flooded rice(TFR),controlled irrigation transplanting rice(CTR),intermittent irrigation transplanting rice(ITR)and wet irrigation transplanting rice(WTR).Among them,TFR was the control.The results showed that the peaks of the water consumption amount,intensity and its modulus coefficient of the seven treatments all appeared in the middle tillering and the jointing booting stages.The total water consumption amount(ET)and average water consumption intensity of DDSR,WDSR,FDSR and WTR were lower than those of TFR,CTR and ITR.The maximum water use efficiency of yield(WUEy)occurred in DDSR with a value of 3.8 kg·m^(-3).WUEy of DDSR,WDSR and FDSR were significantly higher than those of TFR,CTR and ITR.In the middle tillering and the heading and flowering stages,the water consumption amount of each treatment had a positive effect on yield formation,and the water consumption amount in the late tillering stage had a negative effect on yield formation.The relationship between ET and yield(Y)of dry direct seeding and transplanting planting models showed a quadratic function curve.ET of transplanting planting model had a significant positive impact on Y,and ET of dry direct seeding planting model had no impact on Y.DDSR had the least total water consumption of 199.8 mm·m^(-2),the lowest water consumption intensity of 2.0 mm·d^(-1) and the greatest water use efficiency of 3.8 kg·m^(-3),which suggested that DDSR had the most significant water saving effect.The combination of dry direct seeding planting model and drip irrigation scheme would be a good option for determining a water-saving rice planting model in northeast China.展开更多
Energy saving and CO2 emissions reduction are critical tasks currently,and great effort has been made by Chinese government. Renewable energy consumption and CO2 emissions and reduction plan in China are introduced in...Energy saving and CO2 emissions reduction are critical tasks currently,and great effort has been made by Chinese government. Renewable energy consumption and CO2 emissions and reduction plan in China are introduced in this paper. Analysis is also made on present status and prospect of geothermal power generation and direct use in China respectively. Now,there is a new understanding of geothermal resources,and hot dry rock,considered as the future of geothermal resources,is likely used to generate electricity.展开更多
In the last two decades, the global interest on farmland grew at a remarkable pace. As a consequence, million hectares of land exchanged hands. The ways the transfers happened combined with their geographic concentrat...In the last two decades, the global interest on farmland grew at a remarkable pace. As a consequence, million hectares of land exchanged hands. The ways the transfers happened combined with their geographic concentration in Sub-Saharian Africa, have earned the phenomenon the name of "land grab". The agricultural sector considered a "sunset industry" when commodities prices were declining, is now attractive to financial investors. These foreign investments may be good as they may improve agricultural productivity or instead bad as they may benefit only financial investors. Some results in terms of environmental and local communities' worsening conditions have already emerged. This paper aims to investigate what drives the big size transfers of land, to empirically estimate their effects in terms of local employment and to assess the environmental effects produced by the rapid transformation in the use of vast amount of land in terms of CO2 emissions. It is also proposed to use the estimation in terms of local employment impact as a way of distinguishing between foreign direct investment and land grabbing.展开更多
The demand for energy in Kenya, especially for electricity, is increasing rapidly due to population growth, decentralization of governance, and technological and industrial development. Hydroelectricity, the core sour...The demand for energy in Kenya, especially for electricity, is increasing rapidly due to population growth, decentralization of governance, and technological and industrial development. Hydroelectricity, the core source of power, has proved unreliable due to the rapid climate change. In response, the country has ventured into other renewable sources to counter the issues posed by the alternative nonrenewable sources such as unreliability, high costs, and environmental degradation as seen with the use of diesel and kerosene. The purpose of this research is to determine the viability of setting up a large-scale concentrated solar power plantation in Kenya that will assist in stabilizing Kenya’s energy demand and supply as well as increase its affordability. The project is divided into three phases. The first phase conducts an overlay analysis to determine the Kenya’s solar energy potential. The results show that the northern region has the highest potential. The second step involves the creation of an exclusion mask which eliminates the unsuitable land forms and Land Use Land Cover. Based on the results, the best ten sites are situated in Turkana and Marsabit counties. The final phase involves the evaluation of the potential capacity of power that could be generated per square kilometer. The study finds out that the potential varies based on the technologies: parabolic trough, linear Fresnel reflector, or dish systems.展开更多
Objective image quality measure, which is a fundamental and challenging job in image processing, evaluates the image quality consistently with human perception automatically. On the assumption that any image distortio...Objective image quality measure, which is a fundamental and challenging job in image processing, evaluates the image quality consistently with human perception automatically. On the assumption that any image distortion could be modeled as the difference between the directional projection-based maps of reference and distortion images, we propose a new objective quality assessment method based on directional projection for full reference model. Experimental results show that the proposed metrics are well consistent with the subjective quality score.展开更多
A novel direct writing technique using submicron-diameter fibers is presented. This technique adopts contact mode in the process of writing, and submicron lines with different widths have been obtained. Experimental r...A novel direct writing technique using submicron-diameter fibers is presented. This technique adopts contact mode in the process of writing, and submicron lines with different widths have been obtained. Experimental results demonstrate that the resolution of this technique can be smaller than the exposure wavelength of 442 nm, and 380-nm-wide line is achieved. In addition, the distribution of light fields in the photoresist layer is analyzed by finite-difference time-domain method.展开更多
基金supported by open fund of state key laboratory of operation and control of renewable energy&storage systems(China electric power research institute)(No.NYB51202201709).
文摘The time-of-use(TOU)strategy can effectively improve the energy consumption mode of customers,reduce the peak-valley difference of load curve,and optimize the allocation of energy resources.This study presents an Optimal guidance mechanism of the flexible load based on strategies of direct load control and time-of-use.First,this study proposes a period partitioning model,which is based on a moving boundary technique with constraint factors,and the Dunn Validity Index(DVI)is used as the objective to solve the period partitioning.Second,a control strategy for the curtailable flexible load is investigated,and a TOU strategy is utilized for further modifying load curve.Third,a price demand response strategy for adjusting transferable load is proposed in this paper.Finally,through the case study analysis of typical daily flexible load curve,the efficiency and correctness of the proposed method and model are validated and proved.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11574362,61210014,and 11374340the Innovative Clean-Energy Research and Application Program of Beijing Municipal Science and Technology Commission under Grant No Z151100003515001
文摘The resonant excitation is used to generate photo-excited carriers in quantum wells to observe the process of the carriers transportation by comparing the photoluminescence results between quantum wells with and without a p-n junction. It is observed directly in experiment that most of the photo-excited carriers in quantum wells with a p-n junction escape from quantum wells and form photoeurrent rather than relax to the ground state of the quantum wells. The photo absorption coei^cient of multiple quantum wells is also enhanced by a p-n junction. The results pave a novel way for solar cells and photodetectors making use of low-dimensional structure.
基金2013 Six Peak Talents in Jiangsu Province,Project No.WSN-022333 Key Talents of Science and Technology in Jiangsu Province,Project No.BRA2012094+1 种基金Scientific Project of Traditional Chinese Medicine of Jiangsu Province,Project No.LZ131952011 Project of Scientific Technology and Social Development in Yangzhou,Project No.YZ2011084
文摘Dear Editor, In 2011, Son et al. (2011) reported that the forced expression of selected transcription factors is sufficient to convert mouse and human fibroblasts into induced motor neurons (iMNs). The authors used three factors (Ascll, Brn2, and Mytll) to convert fibroblasts into neuronal-like ceils. After confirming that the cells had neuronal morphology, but with absence of motor neuron markers, eight candidate transcription factors were added, which participate in various stages of motor neuron specification. As expected, a significant number of motor cells emerged with known characteristics of cultured embryonic motor neurons.
文摘BACKGROUND Statins have an important and well-established role in the prevention of atherosclerotic cardiovascular disease(ASCVD).However,several studies have reported widespread underuse of statins in various practice settings and populations.Review of relevant literature reveals opportunities for improvement in the implementation of guideline-directed statin therapy(GDST).AIM To examine the impact of cardiologist intervention on the use of GDST in the ambulatory setting.METHODS Patients with at least one encounter at the adult Internal Medicine Clinic(IMC)and/or Cardiology Clinic(CC),who had an available serum cholesterol test performed,were evaluated.The 2 comparison groups were defined as:(1)Patients only seen by IMC;and(2)Patients seen by both IMC and CC.Patients were excluded if variables needed for calculation of ASCVD risk scores were lacking,and if demographic information lacked guideline-directed treatment recommendations.Data were analyzed using student t-tests or χ^2,as appropriate.Analysis of Variance was used to compare rates of adherence to GDST.RESULTS A total of 268 patients met the inclusion criteria for this study;211 in the IMC group and 57 in the IMC-CC group.Overall,56%of patients were female,mean age 56 years(±10.65,SD),22%Black or African American,56%Hispanic/Latino,14%had clinical ASCVD,13%current smokers,66%diabetic and 63%hypertensive.Statin use was observed in 55%(n=147/268)of the entire patient cohort.In the IMC-CC group,73.6%(n=42/57)of patients were prescribed statin therapy compared to 50.7%(n=107/211)of patients in the IMC group(P=0.002).In terms of appropriate statin use based on guidelines,there was no statistical difference between groups[IMC-CC group 61.4%(n=35/57)vs IMC group,55.5%(n=117/211),P=0.421].Patients in the IMC-CC group were older,had more cardiac risk factors and had higher proportions of non-white patients compared to the IMC group(P<0.02,all).CONCLUSION Although overall use of GDST was suboptimal,there was no statistical difference in appropriate statin use based on guidelines between groups managed by general internists alone or co-managed with a cardiologist.These findings highlight the need to design and implement strategies to improve adherence rates to GDST across all specialties.
基金supported by the National Natural Science Foundation of China(31971845,32061143038)the China Postdoctoral Science Foundation(2021 M691179)+3 种基金the China Agriculture Research System(CARS-01-20)the Program of Introducing Talents of Discipline to Universities in China(the 111 Project no.B14032)the Program for Changjiang Scholars and Innovative Research Team in University of China(IRT1247)a grant from the Bill and Melinda Gates Foundation(OPP51587)。
文摘Labor scarcity requires double-season rice to be planted by direct seeding as an alternative to transplanting. Only ultrashort-duration varieties can be used in direct-seeded, double-season rice(DSD) in central China where thermal time is limited. Whether ultrashort-duration varieties grown in DSD can be as productive and efficient in nitrogen(N) use as transplanted double-season rice(TPD) remains unclear. Field experiments were conducted in Hubei province, central China with two establishment methods(DSD,TPD) and three N rates in the early and late seasons of 2017 and 2018. Nitrogen treatments included zero-N control(N0), total N rate of 60 kg N ha;with equal splits at basal, midtillering, and panicle initiation(N1), and weekly N application at 15 kg ha;from seeding/transplanting to heading(N2). Both early-and late-season rice under DSD matured within 95 days, on average 9 days shorter than rice under TPD. The grain yield of DSD was comparable to or higher than that of TDP in both seasons, although the daily yield was significantly higher under DSD than under TDP. Before heading, DSD had higher leaf area,stem number, intercepted radiation, and radiation use efficiency than TPD, which compensated for the negative effect of short growth duration on biomass production. Total dry weight and harvest index under DSD were comparable to or higher than those under TDP. In general, the recovery efficiency of fertilizer-N under DSD was higher than that under TPD, but the reverse was true for physiological N use efficiency. Thus, there was no significant difference in agronomic N use efficiency between DSD and TPD. These results suggested that DSD with ultrashort-duration varieties is a promising alternative to TPD in central China for maintaining high grain yield and N fertilizer use efficiency with less labor input.
基金Supported by the National Natural Science Foundation of China under Grant Nos 31200545,11274206 and 11574184
文摘We report the results of protein folding (219M, C34, N36, 2KES, 2KHK) by the method of accelerated molecular dynamics (aMD) at room temperature with the implicit solvent model. Starting from the linear structures, these proteins successfully fold to the native structure in a lO0-ns aMD simulation. In contrast, they are failed under the traditional MD simulation in the same simulation time. Then we find that the lowest root mean square deviations of helix structures from the native structures are 0.36 A, 0.63 A, 0.52 A, 1.1 A and 0.78 A. What is more, native contacts, cluster and free energy analyses show that the results of the aMD method are in accordance with the experiment very well. All analyses show that the aMD can accelerate the simulation process, thus we may apply it to the field of computer aided drug designs.
基金supported in part by the grants from the South Carolina Spinal Cord Injury Research Fund(SC SCIRF-2015-I-01,Columbia,SC,USA)the United Soybean Board(USB,Chesterfield,MO,USA)to SKR
文摘All synthetic and natural estrogen receptor agonists, in- cluding the most potent physiological molecule estrogen or estradiol (E2), work typically via activation of nuclear estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). Both ERα and ERβ modulate the expression of a variety of genes in the cells. Neurons and glial cells express ERa and ERβ. Many studies so far from our and other laboratories have firmly established the mode of actions that ERα and ERβ agonists are very promising anti-inflammatory and neuroprotective agents in the treatment of neurodegenera- rive diseases and injuries including spinal cord injury (SCI) (Chakrabarti et al., 2014a).
基金Supported by National Soil Testing and Fertilizer Recommendation Project
文摘Using the evaluation indicator system for arable land fertility in Suiping County,this paper analyzes some factors influencing agricultural production,such as physical and chemical properties of soil,site conditions,soil management,and soil nutrients concerning various types of low-yielding fields in the county. In accordance with the dominant soil constraint factors and main direction of improvement,the lowyielding fields in the county are divided into four types: irrigation improvement type,waterlogging drainage type,barren soil fertilization and barrier layer type. Finally this paper offers specific guidance on the construction of arable land.
基金Supported by the National Natural Science Foundation of China under Grant Nos 91336103,10934010 and 61078026
文摘The optical frequency comb has been widely used in precision measurement. In this study, a multi-peak fitting approach is first proposed to fit the two-photon transition spectrum which overlaps with the neighboring transition in Rb-87. The multi-peak fitting approach is used to eliminate the frequency shift affected by the neighboring transition. With locking the carrier envelope offset frequency at 1/4 repetition frequency, the transition frequency is measured to be 770569132739.9 +/- 5.8 kHz, which agrees well with the previous result recommended by Comite International des Poids et Mesures.
文摘Conceptually,rural complex is actually a comprehensive sustainable development model for new agricultural and rural areas across industries and functions.From the perspective of rural complex,combined with the actual case of Idyllic Orient in Yangshan,Wuxi,the first rural complex in China,this paper analyzes the current benefits of relevant projects.Considering the basic situation of Luodeli Village in Luquan County,Yunnan Province,the direction,development model and spatial allocation of land use are initially determined.Finally,the overall development path is proposed for Luodeli Village in Luquan County,in order to provide some ideas for its next development.
文摘Strontium has four naturally occurring stable isotopes,84Sr,86Sr,87Sr,and 88Sr,with abundances of 0.56,9.87,approximately 7.04,and 82.53 atomic %,respectively.The 87Sr/86Sr isotope ratio is variable due to the addition of radiogenic 87Sr produced by the beta decay of 87Rb with a half-life of 4.88 ± 0.05 Ga.Thus,
文摘This paper reports a new method of titration for very weak acids and bases using the appearance of incisions on oscillopolarogram to indicate the end-point.This method has the advantages of rapidity,simplicity,no indicator needed as well as good precision.
文摘The assessment of the local community perception of the value of riparian corridors is relevant to understand their attitude towards the conservation of such ecosystem. We conducted a semi-structured survey on the perception and importance attributed to the ecosystem services (ESs) provided by riparian corridors in 368 households across 70 villages located in a buffer zone of 5 km of servitude around the permanent rivers of the Upper Oueme watershed in Benin. We found that local communities easily reported provisioning and cultural ESs than regulating and supporting ones, indicating their misunderstanding of the main role of riparian corridor. Moreover, the supply of cropping areas was perceived as the most important ES. Educated respondents and high-income households had more knowledge of regulating ESs and supporting ESs, respectively. Overall, the highly perceived importance of the provision of cropping areas indicates a potential risk of agricultural encroachment of riparian corridors. We suggest the consideration of the current local perception of riparian corridor’s role in designing a sound environmental education aiming at the change of local population’s perception. This perception shift will promote a sustainable management of the riparian corridors.
文摘Beijing has been experiencing a severe shortage of water. At present serious wastes of water resources result from the unreasonable structure of water uses in various industries sectors. The current conditions of the municipal water use structure and its changes in the industrial sectors were analysed and discussed in terms of the indicators, such as direct water use coefficient, complete water use coefficient, water use multiplier and water reuse rate, by taking a year of 1990s as the base year. Some response strategies for water conservation have been studied and the corresponding recommendations were put forward. All of these have provided a basis for coordinating the relationship between aquatic environment and economic growth in this city, establishing a system for rational utilization of water resources, and promoting the implementation of a strategy for sustainable development.
基金Supported by the National Key Research and Development Program of China(2016YFC040010101)。
文摘Different irrigation schemes have different effects on water consumption in rice production.However,few studies have been conducted on the water consumption processes between dry direct seeding rice and transplanting rice under different irrigation schemes.Water consumption process,water use efficiency and correlation effect of water consumption on yield under different planting models in rice production were investigated in northeast China in 2018.Seven treatments were implemented:drip irrigation dry direct seeding rice(DDSR),wet irrigation dry direct seeding rice(WDSR),flooded irrigation dry direct seeding rice(FDSR),transplanting flooded rice(TFR),controlled irrigation transplanting rice(CTR),intermittent irrigation transplanting rice(ITR)and wet irrigation transplanting rice(WTR).Among them,TFR was the control.The results showed that the peaks of the water consumption amount,intensity and its modulus coefficient of the seven treatments all appeared in the middle tillering and the jointing booting stages.The total water consumption amount(ET)and average water consumption intensity of DDSR,WDSR,FDSR and WTR were lower than those of TFR,CTR and ITR.The maximum water use efficiency of yield(WUEy)occurred in DDSR with a value of 3.8 kg·m^(-3).WUEy of DDSR,WDSR and FDSR were significantly higher than those of TFR,CTR and ITR.In the middle tillering and the heading and flowering stages,the water consumption amount of each treatment had a positive effect on yield formation,and the water consumption amount in the late tillering stage had a negative effect on yield formation.The relationship between ET and yield(Y)of dry direct seeding and transplanting planting models showed a quadratic function curve.ET of transplanting planting model had a significant positive impact on Y,and ET of dry direct seeding planting model had no impact on Y.DDSR had the least total water consumption of 199.8 mm·m^(-2),the lowest water consumption intensity of 2.0 mm·d^(-1) and the greatest water use efficiency of 3.8 kg·m^(-3),which suggested that DDSR had the most significant water saving effect.The combination of dry direct seeding planting model and drip irrigation scheme would be a good option for determining a water-saving rice planting model in northeast China.
文摘Energy saving and CO2 emissions reduction are critical tasks currently,and great effort has been made by Chinese government. Renewable energy consumption and CO2 emissions and reduction plan in China are introduced in this paper. Analysis is also made on present status and prospect of geothermal power generation and direct use in China respectively. Now,there is a new understanding of geothermal resources,and hot dry rock,considered as the future of geothermal resources,is likely used to generate electricity.
文摘In the last two decades, the global interest on farmland grew at a remarkable pace. As a consequence, million hectares of land exchanged hands. The ways the transfers happened combined with their geographic concentration in Sub-Saharian Africa, have earned the phenomenon the name of "land grab". The agricultural sector considered a "sunset industry" when commodities prices were declining, is now attractive to financial investors. These foreign investments may be good as they may improve agricultural productivity or instead bad as they may benefit only financial investors. Some results in terms of environmental and local communities' worsening conditions have already emerged. This paper aims to investigate what drives the big size transfers of land, to empirically estimate their effects in terms of local employment and to assess the environmental effects produced by the rapid transformation in the use of vast amount of land in terms of CO2 emissions. It is also proposed to use the estimation in terms of local employment impact as a way of distinguishing between foreign direct investment and land grabbing.
文摘The demand for energy in Kenya, especially for electricity, is increasing rapidly due to population growth, decentralization of governance, and technological and industrial development. Hydroelectricity, the core source of power, has proved unreliable due to the rapid climate change. In response, the country has ventured into other renewable sources to counter the issues posed by the alternative nonrenewable sources such as unreliability, high costs, and environmental degradation as seen with the use of diesel and kerosene. The purpose of this research is to determine the viability of setting up a large-scale concentrated solar power plantation in Kenya that will assist in stabilizing Kenya’s energy demand and supply as well as increase its affordability. The project is divided into three phases. The first phase conducts an overlay analysis to determine the Kenya’s solar energy potential. The results show that the northern region has the highest potential. The second step involves the creation of an exclusion mask which eliminates the unsuitable land forms and Land Use Land Cover. Based on the results, the best ten sites are situated in Turkana and Marsabit counties. The final phase involves the evaluation of the potential capacity of power that could be generated per square kilometer. The study finds out that the potential varies based on the technologies: parabolic trough, linear Fresnel reflector, or dish systems.
文摘Objective image quality measure, which is a fundamental and challenging job in image processing, evaluates the image quality consistently with human perception automatically. On the assumption that any image distortion could be modeled as the difference between the directional projection-based maps of reference and distortion images, we propose a new objective quality assessment method based on directional projection for full reference model. Experimental results show that the proposed metrics are well consistent with the subjective quality score.
基金supported by the National Natural Science Foundation of China under Grant Nos.60778030supported by the National Natural Science Foundation of China under Grant Nos.60678037
文摘A novel direct writing technique using submicron-diameter fibers is presented. This technique adopts contact mode in the process of writing, and submicron lines with different widths have been obtained. Experimental results demonstrate that the resolution of this technique can be smaller than the exposure wavelength of 442 nm, and 380-nm-wide line is achieved. In addition, the distribution of light fields in the photoresist layer is analyzed by finite-difference time-domain method.