This paper contributes to the assessment of China's rural labor markets. According to our data, the increase in off-farm employment that China experienced during the 1980s and 1990s continued during the 2000s. Our an...This paper contributes to the assessment of China's rural labor markets. According to our data, the increase in off-farm employment that China experienced during the 1980s and 1990s continued during the 2000s. Our analysis shows that migration has become the most prevalent off-farm activity, although the destination of migrants is shifting from outside of one's province to destinations closer to home. The present paperfinds that large shares of male and female individuals, especially those under 40 years, are working off the farm. These findings represent an important contribution to the labor economics field. First, the results of the present paper reveal that the labor transition from the agricultural sector to the non-agricultural sector for key segments of China's rural labor force is nearly complete. Second, although a large share of China "s rural labor force work in agriculture, most of these workers are older men and women (and likely would not be willing to take low-wage, labor-intensive jobs). Third, the rising unskilled wage rate in China is partially a result of the tightening of the labor force in the young age cohorts. Finally, due to factors associated with the one child policy and other demographic transition forces, successive age cohorts will continue to fall in absolute number in the coming decade. Assuming China's growth continues, we expect to see further wage increases since it will take higher wages to coax more workers to work off the farm.展开更多
Recently, as location-based social network(LBSN) rapidly grow, point-of-interest(POI) recommendation has become an important way to help people locate interesting places. Nowadays, there have been deep studies conduct...Recently, as location-based social network(LBSN) rapidly grow, point-of-interest(POI) recommendation has become an important way to help people locate interesting places. Nowadays, there have been deep studies conducted on the geographical and social influence in the point-of-interest recommendation model based on the rating prediction. The fact is, however, relying solely on the rating fails to reflect the user's preferences very accurately, because the users are most concerned with the list of ranked point-of-interests(POIs) on the actual output of recommender systems. In this paper, we propose a co-pairwise ranking model called Geo-Social Bayesian Personalized Ranking model(GSBPR), which is based on the pairwise ranking with the exploiting geo-social correlations by incorporating the method of ranking learning into the process of POI recommendation. In this model, we develop a novel BPR pairwise ranking assumption by injecting users' geo-social preference. Based on this assumption, the POI recommendation model is reformulated by a three-level joint pairwise ranking model. And the experimental results based on real datasets show that the proposed method in this paper enjoys better recommendation performance compared to other state-of-the-art POI recommendation models.展开更多
This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demogra...This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demographic and Health Surveys(DHS).Results from both fixed effects(FE)and instrumental variable(IV)estimates show that using non-solid cooking fuel significantly improves the nutrition outcomes of under-five children.Compared with their peers from households mainly using solid fuel,children from households mainly using non-solid fuel exhibit a lower probability of experiencing stunting(by 5.9 percentage points)and being underweight(by 1.2 percentage points).Our further investigation provides evidence for several underlying mechanisms,such as improved indoor air quality,induced reduction in children’s respiratory symptoms,benefits on maternal health,and reduction in maternal time spent on fuel collection or cooking.Heterogenous analyses suggest that the nutrition benefits of using non-solid cooking fuel are more prominent among boys,children above three years old,and those from households of lower socioeconomic status,rural areas,and Southeast Asia.展开更多
Using three-wave survey data for four villages of Jiangsu Province in China, the present paper examines whether and to what extent off-farm employment affects the technical efficiency of agricultural production. The l...Using three-wave survey data for four villages of Jiangsu Province in China, the present paper examines whether and to what extent off-farm employment affects the technical efficiency of agricultural production. The level of technical efficiency is measured using a stochastic frontier production function approach. Based on estimation results from instrumental variable panel quantile regressions we find that there is a positive significant effect of off-farm employment on the level of farm technical efficiency. We also find that fragmentation of farmland is a barrier to the improvement of technical efficiency. In addition, we find a downward trend in the level of agricultural technical efficiency among our sample. Therefore, the Chinese Government should stimulate agricultural mechanization and the development of farming techniques to improve technical efficiency in the context of increasing off-farm employment.展开更多
In the post-genome-wide association study era,multi-omics techniques have shown great power and poten-tial for candidate gene mining and functional genomics research.However,due to the lack of effective data integrati...In the post-genome-wide association study era,multi-omics techniques have shown great power and poten-tial for candidate gene mining and functional genomics research.However,due to the lack of effective data integration and multi-omics analysis platforms,such techniques have not still been applied widely in rape-seed,an important oil crop worldwide.Here,we report a rapeseed multi-omics database(BnlR;http:/l yanglab.hzau.edu.cn/BnlR),which provides datasets of six omics including genomics,transcriptomics,variomics,epigenetics,phenomics,and metabolomics,as well as numerous"variation-gene expression-phenotype"associations by using multiple statistical methods.In addition,a series of multi-omics search and analysis tools are integrated to facilitate the browsing and application of these datasets.BnlR is the most comprehensive multi-omics database for rapeseed so far,and two case studies demonstrated its power to mine candidate genes associated with specific traits and analyze their potential regulatory mechanisms.展开更多
We recently reported that zacopride is a selective inward rectifier potassium current (IK1 ) channel agonist, suppressing ventricular arrhythmias without affecting atrial arrhythmias. The present study aimed to invest...We recently reported that zacopride is a selective inward rectifier potassium current (IK1 ) channel agonist, suppressing ventricular arrhythmias without affecting atrial arrhythmias. The present study aimed to investigate the unique pharmacological properties of zacopride. The whole-cell patch-clamp technique was used to study IK1 currents in rat atrial myocytes and Kir2.x currents in human embryonic kidney (HEK)-293 cells transfected with inward rectifier potassium channel (Kir)2.1, Kir2.2, Kir2.3, or mutated Kir2.1 (at phosphorylation site S425L). Western immunoblots were performed to estimate the relative protein expression levels of Kir2.x in rat atria and ventricles. Results showed that zacopride did not affect the IK1 and transmembrane potential of atrial myocytes. In HEK293 cells, zacopride increased Kir2.1 homomeric channels by 40.7%±9.7% at 50 mV, but did not affect Kir2.2 and Kir2.3 homomeric channels, and Kir2.1-Kir2.2, Kir2.1-Kir2.3 and Kir2.2-Kir2.3 heteromeric channels. Western immunoblots showed that similar levels of Kir2.3 protein were expressed in rat atria and ventricles, but atrial Kir2.1 protein level was only 25% of that measured in the ventricle. In addition, 5-hydroxytryptamine (5-HT) 3 receptor was undetectable, whereas 5-HT 4 receptor was weakly expressed in HEK293 cells. The Kir2.1-activating effect of zacopride in these cells was abolished by inhibition of protein kinase A (PKA), but not PKC or PKG. Furthermore, zacopride did not activate the mutant Kir2.1 channel in HEK293 cells but selectively activated the Kir2.1 homomeric channel via a PKA-dependent pathway, independent to that of the 5-HT receptor.展开更多
Achieving color-tunable emission in single-component organic emitters with multistage stimuli-responsiveness is of vital significance for intelligent optoelectronic applications,but remains enormously challenging.Here...Achieving color-tunable emission in single-component organic emitters with multistage stimuli-responsiveness is of vital significance for intelligent optoelectronic applications,but remains enormously challenging.Herein,we present an unprecedented example of a color-tunable single-component smart organic emitter(DDOP)that simultaneously exhibits multistage stimuli-responsiveness and multimode emissions.DDOP based on a highly twisted amide-bridged donor-tcceptor-donor structure has been found to facilitate intersystem crossing,form multimode emissions,and generate multiple emissive species with multistage stimuli-responsiveness.DDOP pristine crystalline powders exhibit abnormal excitation-dependent emissions from a monomer-dominated blue emission centered at 470 nm to a dimer-dominated yellow emission centered at 550 nm through decreasing the ultraviolet(UV)excitation wavelengths,whereas DDOP single crystals show a wide emission band with a main emission peak at 585 nm when excited at different wavelengths.The emission behaviors of pristine crystalline powders and single crystals are different,demonstrating emission features that are closely related to the aggregation states.The work has developed color-tunable single-component organic emitters with simultaneous multistage stimuli-responsiveness and multimode emissions,which is vital for expanding intelligent optoelectronic applications,including multilevel information encryption,multicolor emissive patterns,and visual monitoring of UV wavelengths.展开更多
Objective To investigate effects of glucose excursion on the oxidative/antioxidative system in subjects with different types of glucose regulation. Methods A total of 30 individuals with normal glucose regulation (NGR...Objective To investigate effects of glucose excursion on the oxidative/antioxidative system in subjects with different types of glucose regulation. Methods A total of 30 individuals with normal glucose regulation (NGR), 27 subjects with impaired glucose regulation (IGR) and 27 subjects with newly diagnosed type 2 diabetes mellitus (T2DM) were selected and recruited for 3 days’ continuous glucose monitor system (CGMS) assessment. The data from CGMS was used to calculate the mean amplitude of glycemic excursion (MAGE), mean blood glucose (MBG) and its standard deviation (SDBG), area under the ROC curve when the blood glucose 5.6 mmol/L within 24 h (AUC 5.6), mean of daily differences (MODD), and mean postprandial glucose excursion (MPPGE). In all groups, the content or activity of malondialdehyde (MDA), total antioxidation capacity (TAOC) and glutathione peroxidase (GSH‐Px) were detected. Results Glucose excursion parameters of subjects with T2DM or IGR were higher than those of NGR subjects (P0.05 or 0.01). Moreover, Glucose excursion parameters of T2DM subjects were higher than those of IGR subjects (P0.05 or 0.01). Subjects with T2DM or IGR had significant higher MDA levels and lower GSH‐Px/MDA and TAOC/MDA levels compared to NGR subjects (P0.01). T2DM subjects had even higher MDA levels and lower GSH‐Px/MDA levels than IGR (P0.05 or 0.01). According to the median of normal population for MAGE, T2DM and IGR subjects were divided into MAGE2.6mmol/L Group and MAGE≤2.6mmol/L Group. MAGE2.6mmol/L Group had higher levels of MDA and lower levels of GSH‐Px/MDA than MAGE≤2.6mmol/L Group (P0.05). There was no significant difference between the two groups (P0.05) in terms of the levels of TAOC/MDA. Pearson correlation analysis showed that MDA was positively correlated with FPG, 2hPG, MAGE, and SBP. GSH‐Px/MDA was negatively correlated with MAGE and TC. TAOC/MDA was negatively correlated with FPG. Partial correlation analysis showed that the relationship between MDA and MAGE, GSH‐Px/MDA, and MAGE remained展开更多
Covalent organic frameworks(COFs) are attractive porous crystalline materials with extremely high stability, easy functionalization, and open channels, which are expected to be unique ion conductors/transporters in li...Covalent organic frameworks(COFs) are attractive porous crystalline materials with extremely high stability, easy functionalization, and open channels, which are expected to be unique ion conductors/transporters in lithium ion batteries(LIBs). Despite recent advances, low ion conductivity and low transference number, resulting in low charging/discharging rate, low energy density, and short battery life, are the main issues that limit their direct application as solid electrolytes in LIBs. Here, we designed and synthesized a novel polyimide COF, namely, TAPA-PDI-COF, with abundant C=O groups, which has been successfully employed as high-performance solid electrolytes by doping TAPA-PDI-COF and succinonitrile(SN). Both the well-defined nanochannels of COFs and SN confined in the well-aligned channels restricted the free migration of anions, while C=O on COFs and CN groups of SN enhanced Li^(+) transport, thus achieving a high ion conductivity of 0.102 m S cm^(-1)at 80 °C and a high lithium-ion transference number of 0.855 at room temperature. According to density functional theory(DFT)calculations, Li-ion migration mainly adopted in-plane transport rather than the axial pathway, which may be due to the shorter hopping distances in the planar pathway. The results suggest an effective strategy for the design and development of all-solidstate ionic conductors for achieving high-performance LIBs.展开更多
Chronic alcohol consumption causes liver steatosis,cell death,and inflammation.Melatonin(MLT)is reported to alleviate alcoholic liver disease(ALD)-induced injury.However,its direct regulating targets in hepatocytes ar...Chronic alcohol consumption causes liver steatosis,cell death,and inflammation.Melatonin(MLT)is reported to alleviate alcoholic liver disease(ALD)-induced injury.However,its direct regulating targets in hepatocytes are not fully understood.In the current study,a cell-based screening model and a chronic ethanol-fed mice ALD model were used to test the protective mechanisms of MLT.MLT ameliorated ethanol-induced hepatocyte injury in both cell and animal models(optimal doses of 10μmol/L and 5 mg/kg,respectively),including lowered liver steatosis,cell death,and inflammation.RNA-seq analysis and loss-of-function studies in AML-12 cells revealed that telomerase reverse transcriptase(TERT)was a key downstream effector of MLT.Biophysical assay found that epidermal growth factor receptor(EGFR)on the hepatocyte surface was a direct binding and regulating target of MLT.Liver specific knock-down of Tert or Egfr in the ALD mice model impaired MLT-mediated liver protection,partly through the regulation of nuclear brahma-related gene-1(BRG1).Long-term administration(90 days)of MLT in healthy mice did not cause evident adverse effect.In conclusion,MLT is an efficacious and safe agent for ALD alleviation.Its direct regulating target in hepatocytes is EGFR and downstream BRG1-TERT axis.MLT might be used as a complimentary agent for alcoholics.展开更多
Seed-borne bacterial pathogens cause severe yield loss and biotoxin contamination in rice,leading to increasing concern on the global food supply and environmental safety.Plant native microbes play an important role i...Seed-borne bacterial pathogens cause severe yield loss and biotoxin contamination in rice,leading to increasing concern on the global food supply and environmental safety.Plant native microbes play an important role in defending against diseases,but their actions are often influ-enced by the chemical fungicides applied in the field.Here,Bacillus licheniformis mmj was isolated from rice spikelet,which uniquely showed not only fungicide-responsiveness but also broad-spectrum antimicrobial activity against major rice bacterial pathogens including Xanthomonas oryzae pv.oryzae,Burkholderia plantari and Burkholderia glumae.To understand the hallmark underlying the environmental adaptation and anti-microbial activity of B.licheniformis mmj,the genome sequence was determined by SMRT and subjected to bioinformatics analysis.Genome sequence analysis enabled the identification of a set of antimicrobial-resistance and antibacterial activity genes together with an array of harsh environment-adaptive genes.Moreover,B.licheniformis mmj metabolites were analyzed with gas chromatography coupled to triple quadrupole mass spectrometry,and the volatile components that were linked with the antimicrobial activity were preliminarily profiled.Collectively,the present findings reveal the genomic and metabolic landscapes underlying fungicide-responsive B.licheniformis,which offers a new opportunity to design harsh environment-adaptive biopesticides to cope with prevalent bacterial phytopathogens.展开更多
Incompletely closed glumes, germination on panicle and disease are three important factors causing poor seed quality of hybrid rice. To determine how many and which categories should be classified to meet the demand f...Incompletely closed glumes, germination on panicle and disease are three important factors causing poor seed quality of hybrid rice. To determine how many and which categories should be classified to meet the demand for seed in rice production, the effects of various degrees of incompletely closed glumes, germination on panicle and disease on germination percentage at the harvest and after storage for six months were studied by standard germination percentage test. Six categories of seeds with germ (germinated seeds), severe disease, incompletely closed glumes, spot disease, fine fissure and normal seeds were inspected and then treated separately. Images of the five hybrid rice seed (Jinyou 402, Shanyou 10, Zhongyou 27, Jiayou 99 and Ⅱ you 3207) were acquired with a self-developed machine vision system. Each image could be processed to get the feature values of seed region such as length, width, ratio of length to width, area, solidity and hue. Then all the images of normal seeds were calculated to draw the feature value ranges of each hybrid rice variety. Finally, an image information base that stores typical images and related feature values of each variety was established. This image information base can help us to identify the classification limit of characteristics, and provide the reference of the threshold selection. The management of large numbers of pictures and the addition of new varieties have been supported. The research laid a foundation for extracting image features of hybrid rice seed, which is a key approach to future quality inspection with machine vision.展开更多
To enhance the efficiency of system modeling and optimization in the conceptual design stage of satellite parameters,a system modeling and optimization method based on System Modeling Language and Co-evolutionary Algo...To enhance the efficiency of system modeling and optimization in the conceptual design stage of satellite parameters,a system modeling and optimization method based on System Modeling Language and Co-evolutionary Algorithm is proposed.At first,the objectives of satellite mission and optimization problems are clarified,and a design matrix of discipline structure is constructed to process the coupling relationship of design variables and constraints of the orbit,payload,power and quality disciplines.In order to solve the problem of increasing nonlinearity and coupling between these disciplines while using a standard collaborative optimization algorithm,an improved genetic algorithm is proposed and applied to system-level and discipline-level models.Finally,the CO model of satellite parameters is solved through the collaborative simulation of Cameo Systems Modeler(CSM)and MATLAB.The result obtained shows that the method proposed in this paper for the conceptual design phase of satellite parameters is efficient and feasible.It can shorten the project cycle effectively and additionally provide a reference for the optimal design of other complex projects.展开更多
Wavelength-tunable organic semiconductor lasers based on mechanically stretchable polydimethylsiloxane (PDMS) gratings were developed. The intrinsic stretchability of PDMS was explored to modulate the period of the di...Wavelength-tunable organic semiconductor lasers based on mechanically stretchable polydimethylsiloxane (PDMS) gratings were developed. The intrinsic stretchability of PDMS was explored to modulate the period of the distributed feedback gratings for fine tuning the lasing wavelength. Notably, elastic lasers based on three typical light-emitting molecules show com-parable lasing threshold values analogous to rigid devices and a continuous wavelength tunability of about 10 nm by mechanic-al stretching. In addition, the stretchability provides a simple solution for dynamically tuning the lasing wavelength in a spec-tral range that is challenging to achieve for inorganic counterparts. Our work has provided a simple and efficient method of fab-ricating tunable organic lasers that depend on stretchable distributed feedback gratings, demonstrating a significant step in the advancement of flexible organic optoelectronic devices.展开更多
A tilt-correction adaptive optical system installed on the 430 mm Solar Telescope of Nanjing University has been put in operation. It consists of a tip-tilt mirror, a correlation tracker and an imaging CCD camera. An ...A tilt-correction adaptive optical system installed on the 430 mm Solar Telescope of Nanjing University has been put in operation. It consists of a tip-tilt mirror, a correlation tracker and an imaging CCD camera. An absolute difference algorithm is used for detecting image motion in the correlation tracker. The sampling frequency of the system is 419 Hz. We give a description of the system's configuration, an analysis of its performance and a report of our observational results. A residual jitter of 0.14 arcsec has been achieved. The error rejection bandwidth of the system can be adjusted in the range 5-28 Hz according to the beacon size and the strength of atmospheric turbulence.展开更多
Background: The purpose of this study was to analyze the effects of all clinical characteristics on the overall survival time, in order to provide a basis for determining the prognostic factor of patients with pancre...Background: The purpose of this study was to analyze the effects of all clinical characteristics on the overall survival time, in order to provide a basis for determining the prognostic factor of patients with pancreatic cancer. Methods: A total of 103 pancreatic cancer patients were admitted to the Department of Radiotherapy and Chemotherapy of the Ruijin Hospital, Shanghai Jiaotong University School of Medicine, between January 2002 and December 2012. There were 68 men and 35 women; the median age was 62 years. Diagnoses of pancreatic cancer in all patients were confirmed by histopathology, cytology, or clinical diagnosis. The Kaplan-Meier method was performed to calculate the overall survival rate. The log-rank method was used to examine the univariate analysis. The Cox regression model was performed for multivariate analysis. Results: The median survival time was 293 days, the 1-, 2-, and 3-year survival rates were 27.18%, 5.83%, and 1.94%, respectively. Cox regression analysis revealed that age (P=0.015), Karnofsky performance status (PS) (P=0.002), surgical types (P〈0.001), and platelet counts (P〈0.001) were independent prognostic factors affecting the overall survival of patients with pancreatic cancer. Conclusions" Pancreatic cancer had a poor prognosis, the general physical condition, age, the availability of radical surgery, and platelet counts were factors influencing the overall survival of patients with pancreatic cancer.展开更多
Fizzy-related protein homolog 1 (FZR1) mainly functions as a specific activator of the anaphase-promotingcomplex/cyclosome (APC/C) in the cell cycle and controls the G0 and G1 phases of the cell cycle. We highlightrec...Fizzy-related protein homolog 1 (FZR1) mainly functions as a specific activator of the anaphase-promotingcomplex/cyclosome (APC/C) in the cell cycle and controls the G0 and G1 phases of the cell cycle. We highlightrecent work that has studied the role of FZR1 in tumorigenesis, growth, differentiation, and genome stability throughcell-cycle control. We summarize the current state of knowledge regarding FZR1 structure, function, and the distinctways of APC/C dysregulation in solid tumors and hematologic malignancies. We also discuss novel approaches fortargeting the FZR1 as a cancer therapy and research area for future work.展开更多
All rivers in the Hexi inland region of Gansu Province, China, originate from the northern slope of the Qilian Mountains. They are located in the southern portion of the region and respectively belong to the three lar...All rivers in the Hexi inland region of Gansu Province, China, originate from the northern slope of the Qilian Mountains. They are located in the southern portion of the region and respectively belong to the three large river systems from east to west, the Shiyang, Heihe and Shule river basins. These rivers are supplied by precipitation, snowmelt and ice-melt runoff from the Qilian Mountain area. Therefore, changes of precipitation and temperature in the upstream watersheds of these rivers have an important effect on changes of mountainous runoff and reasonable utilization of water resources in this region. For this reason, the Qilian Mountain area, upstream watersheds and runoff forming areas of these rivers are chosen as the study area. The change characteristics and variation trend of temperature and precipitation in this area under the backdrop of global warming axe analyzed based on observa- tional data of relational weather and hydrologic stations in the area. Results show that temperatures in the upriver mountain areas of these three large river basins have been increasing, although the increasing degree is differentially affected by global warming. The rising extent of annual and seasonal temperatures in the upstream mountain area of the Shule river basin located in the west- em Qilian Mountains, were all largest over the past 50 years. Precipitation in the upstream mountain areas of Hexi region' three river basins located respectively in the western, middle and eastern Qilian Mountains have been presenting an increasing trend to varying degrees as a whole for more than 50 years. This means that climate in the upstream mountain areas of Hexi region' three river basins are becoming increasingly warmer and moister over the past 50 years, which will be very good for the ecological en- vironment and agricultural production in the region.展开更多
Drawing on a survey of106 secondary vocational schools and 7309 students in two provinces of China, this descriptive paper assesses whether vocational schooling is measuring up to government benchmarks for quality and...Drawing on a survey of106 secondary vocational schools and 7309 students in two provinces of China, this descriptive paper assesses whether vocational schooling is measuring up to government benchmarks for quality and whether poor students are able to access quality schools. We find that secondary vocational schools have met government benchmarks for teacher qualification and training, student opportunities forpractical training and adequate facilities. Furthermore, poor students access schools of similar quality to non-poor students, even though 34percent of poor students do not receive financial aid. We conclude that recent policies are successfully ensuring secondary vocational school quality and equity of access to school quality between poor and non-poor students. However, financial aid policies should be re-examined, such that poor students receive sufficient coverage. Moreover, given that input-based measures only proxy school quality, the government should consider holding schools accountable for outcomes such as student learning.展开更多
In this study, we employed a nonthermal atmospheric pressure plasma(NTAPP) jet to evaluate the effect of plasma treatment on the durability of resin–dentin bonding under a thermocycling challenge. Furthermore, we ass...In this study, we employed a nonthermal atmospheric pressure plasma(NTAPP) jet to evaluate the effect of plasma treatment on the durability of resin–dentin bonding under a thermocycling challenge. Furthermore, we assessed the degradation resistance of plasma-treated collagen under a sodium hypochlorite(NaClO) challenge. We assessed the beneficial effect of NTAPP treatment on the acid-etched dentin–bonding interface by testing the micro-tensile bond strength and examining the morphology. We found that the immediate bonding strength of the dentin significantly increased after NTAPP treatment. Compared with the control group, NTAPP resulted in a more prominent effect on the bonding durability of the dentin–adhesive interface after treatment for 5 or 10 s. Simultaneously, the mechanical strength of dentin collagen under the NaClO challenge was improved. Our results indicate that, in optimal conditions, NTAPP could be a promising method to protect dentin collagen and to improve the bonding durability between dentin and etch-and-rinse adhesives.展开更多
基金funding support from the National Natural Science Foundation of China(71110107028,71033003 and 70803005)the Chinese Academy of Sciences(KZZD-EW-06-02)the Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences(2011RC102 and 2012ZD008)
文摘This paper contributes to the assessment of China's rural labor markets. According to our data, the increase in off-farm employment that China experienced during the 1980s and 1990s continued during the 2000s. Our analysis shows that migration has become the most prevalent off-farm activity, although the destination of migrants is shifting from outside of one's province to destinations closer to home. The present paperfinds that large shares of male and female individuals, especially those under 40 years, are working off the farm. These findings represent an important contribution to the labor economics field. First, the results of the present paper reveal that the labor transition from the agricultural sector to the non-agricultural sector for key segments of China's rural labor force is nearly complete. Second, although a large share of China "s rural labor force work in agriculture, most of these workers are older men and women (and likely would not be willing to take low-wage, labor-intensive jobs). Third, the rising unskilled wage rate in China is partially a result of the tightening of the labor force in the young age cohorts. Finally, due to factors associated with the one child policy and other demographic transition forces, successive age cohorts will continue to fall in absolute number in the coming decade. Assuming China's growth continues, we expect to see further wage increases since it will take higher wages to coax more workers to work off the farm.
基金supported by National Basic Research Program of China (2012CB719905)National Natural Science Funds of China (41201404)Fundamental Research Funds for the Central Universities of China (2042018gf0008)
文摘Recently, as location-based social network(LBSN) rapidly grow, point-of-interest(POI) recommendation has become an important way to help people locate interesting places. Nowadays, there have been deep studies conducted on the geographical and social influence in the point-of-interest recommendation model based on the rating prediction. The fact is, however, relying solely on the rating fails to reflect the user's preferences very accurately, because the users are most concerned with the list of ranked point-of-interests(POIs) on the actual output of recommender systems. In this paper, we propose a co-pairwise ranking model called Geo-Social Bayesian Personalized Ranking model(GSBPR), which is based on the pairwise ranking with the exploiting geo-social correlations by incorporating the method of ranking learning into the process of POI recommendation. In this model, we develop a novel BPR pairwise ranking assumption by injecting users' geo-social preference. Based on this assumption, the POI recommendation model is reformulated by a three-level joint pairwise ranking model. And the experimental results based on real datasets show that the proposed method in this paper enjoys better recommendation performance compared to other state-of-the-art POI recommendation models.
基金This work was supported by the National Natural Science Foundation of China(71861147003 and 71925009).
文摘This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demographic and Health Surveys(DHS).Results from both fixed effects(FE)and instrumental variable(IV)estimates show that using non-solid cooking fuel significantly improves the nutrition outcomes of under-five children.Compared with their peers from households mainly using solid fuel,children from households mainly using non-solid fuel exhibit a lower probability of experiencing stunting(by 5.9 percentage points)and being underweight(by 1.2 percentage points).Our further investigation provides evidence for several underlying mechanisms,such as improved indoor air quality,induced reduction in children’s respiratory symptoms,benefits on maternal health,and reduction in maternal time spent on fuel collection or cooking.Heterogenous analyses suggest that the nutrition benefits of using non-solid cooking fuel are more prominent among boys,children above three years old,and those from households of lower socioeconomic status,rural areas,and Southeast Asia.
基金The authors acknowledge the financial support from the National Natural Science Foundation of China (Grant Nos. 71333012, 71473240 and 71473239).
文摘Using three-wave survey data for four villages of Jiangsu Province in China, the present paper examines whether and to what extent off-farm employment affects the technical efficiency of agricultural production. The level of technical efficiency is measured using a stochastic frontier production function approach. Based on estimation results from instrumental variable panel quantile regressions we find that there is a positive significant effect of off-farm employment on the level of farm technical efficiency. We also find that fragmentation of farmland is a barrier to the improvement of technical efficiency. In addition, we find a downward trend in the level of agricultural technical efficiency among our sample. Therefore, the Chinese Government should stimulate agricultural mechanization and the development of farming techniques to improve technical efficiency in the context of increasing off-farm employment.
基金supported by the National Natural Science Foundation of China(32070559)the National Key Research and Development Plan of China(2021YFF1000100)+2 种基金the China Postdoctoral Science Foundation(2022M710875)the Hubei Hongshan Laboratory(2021HSZD004)and the Developing Bioinformatics Platform in Hainan Yazhou Bay Seed Lab(no.JBGS-B21HJ0001).
文摘In the post-genome-wide association study era,multi-omics techniques have shown great power and poten-tial for candidate gene mining and functional genomics research.However,due to the lack of effective data integration and multi-omics analysis platforms,such techniques have not still been applied widely in rape-seed,an important oil crop worldwide.Here,we report a rapeseed multi-omics database(BnlR;http:/l yanglab.hzau.edu.cn/BnlR),which provides datasets of six omics including genomics,transcriptomics,variomics,epigenetics,phenomics,and metabolomics,as well as numerous"variation-gene expression-phenotype"associations by using multiple statistical methods.In addition,a series of multi-omics search and analysis tools are integrated to facilitate the browsing and application of these datasets.BnlR is the most comprehensive multi-omics database for rapeseed so far,and two case studies demonstrated its power to mine candidate genes associated with specific traits and analyze their potential regulatory mechanisms.
基金supported by the National Natural Science Foundation of China (81170145 to Zhao ZhiQing, 31200864 to Liu QingHua, 31171088 to Cao JiMin)a Science and Technology Program fund from the Health Department of Shanxi Province (2011055 to Zhang Li)
文摘We recently reported that zacopride is a selective inward rectifier potassium current (IK1 ) channel agonist, suppressing ventricular arrhythmias without affecting atrial arrhythmias. The present study aimed to investigate the unique pharmacological properties of zacopride. The whole-cell patch-clamp technique was used to study IK1 currents in rat atrial myocytes and Kir2.x currents in human embryonic kidney (HEK)-293 cells transfected with inward rectifier potassium channel (Kir)2.1, Kir2.2, Kir2.3, or mutated Kir2.1 (at phosphorylation site S425L). Western immunoblots were performed to estimate the relative protein expression levels of Kir2.x in rat atria and ventricles. Results showed that zacopride did not affect the IK1 and transmembrane potential of atrial myocytes. In HEK293 cells, zacopride increased Kir2.1 homomeric channels by 40.7%±9.7% at 50 mV, but did not affect Kir2.2 and Kir2.3 homomeric channels, and Kir2.1-Kir2.2, Kir2.1-Kir2.3 and Kir2.2-Kir2.3 heteromeric channels. Western immunoblots showed that similar levels of Kir2.3 protein were expressed in rat atria and ventricles, but atrial Kir2.1 protein level was only 25% of that measured in the ventricle. In addition, 5-hydroxytryptamine (5-HT) 3 receptor was undetectable, whereas 5-HT 4 receptor was weakly expressed in HEK293 cells. The Kir2.1-activating effect of zacopride in these cells was abolished by inhibition of protein kinase A (PKA), but not PKC or PKG. Furthermore, zacopride did not activate the mutant Kir2.1 channel in HEK293 cells but selectively activated the Kir2.1 homomeric channel via a PKA-dependent pathway, independent to that of the 5-HT receptor.
基金support from the National Natural Science Foundation of China(21835003 and 62274097)the Natural Science Foundation of Jiangsu Province(BE2019120)+2 种基金the Program for Jiangsu Specially-Appointed Professor(RK030STP15001)the Leading Talent of Technological Innovation of National Ten-Thousands Talents Program of Chinathe Postgraduate Research and Practice Innovation Program of Jiangsu Province(KYCX18_0859).
文摘Achieving color-tunable emission in single-component organic emitters with multistage stimuli-responsiveness is of vital significance for intelligent optoelectronic applications,but remains enormously challenging.Herein,we present an unprecedented example of a color-tunable single-component smart organic emitter(DDOP)that simultaneously exhibits multistage stimuli-responsiveness and multimode emissions.DDOP based on a highly twisted amide-bridged donor-tcceptor-donor structure has been found to facilitate intersystem crossing,form multimode emissions,and generate multiple emissive species with multistage stimuli-responsiveness.DDOP pristine crystalline powders exhibit abnormal excitation-dependent emissions from a monomer-dominated blue emission centered at 470 nm to a dimer-dominated yellow emission centered at 550 nm through decreasing the ultraviolet(UV)excitation wavelengths,whereas DDOP single crystals show a wide emission band with a main emission peak at 585 nm when excited at different wavelengths.The emission behaviors of pristine crystalline powders and single crystals are different,demonstrating emission features that are closely related to the aggregation states.The work has developed color-tunable single-component organic emitters with simultaneous multistage stimuli-responsiveness and multimode emissions,which is vital for expanding intelligent optoelectronic applications,including multilevel information encryption,multicolor emissive patterns,and visual monitoring of UV wavelengths.
基金supported by the Shanghai United Developing Technology Project of Municipal Hospitals (SHDC12006101)the Health Bureau of Zhejiang Province (2009B091)
文摘Objective To investigate effects of glucose excursion on the oxidative/antioxidative system in subjects with different types of glucose regulation. Methods A total of 30 individuals with normal glucose regulation (NGR), 27 subjects with impaired glucose regulation (IGR) and 27 subjects with newly diagnosed type 2 diabetes mellitus (T2DM) were selected and recruited for 3 days’ continuous glucose monitor system (CGMS) assessment. The data from CGMS was used to calculate the mean amplitude of glycemic excursion (MAGE), mean blood glucose (MBG) and its standard deviation (SDBG), area under the ROC curve when the blood glucose 5.6 mmol/L within 24 h (AUC 5.6), mean of daily differences (MODD), and mean postprandial glucose excursion (MPPGE). In all groups, the content or activity of malondialdehyde (MDA), total antioxidation capacity (TAOC) and glutathione peroxidase (GSH‐Px) were detected. Results Glucose excursion parameters of subjects with T2DM or IGR were higher than those of NGR subjects (P0.05 or 0.01). Moreover, Glucose excursion parameters of T2DM subjects were higher than those of IGR subjects (P0.05 or 0.01). Subjects with T2DM or IGR had significant higher MDA levels and lower GSH‐Px/MDA and TAOC/MDA levels compared to NGR subjects (P0.01). T2DM subjects had even higher MDA levels and lower GSH‐Px/MDA levels than IGR (P0.05 or 0.01). According to the median of normal population for MAGE, T2DM and IGR subjects were divided into MAGE2.6mmol/L Group and MAGE≤2.6mmol/L Group. MAGE2.6mmol/L Group had higher levels of MDA and lower levels of GSH‐Px/MDA than MAGE≤2.6mmol/L Group (P0.05). There was no significant difference between the two groups (P0.05) in terms of the levels of TAOC/MDA. Pearson correlation analysis showed that MDA was positively correlated with FPG, 2hPG, MAGE, and SBP. GSH‐Px/MDA was negatively correlated with MAGE and TC. TAOC/MDA was negatively correlated with FPG. Partial correlation analysis showed that the relationship between MDA and MAGE, GSH‐Px/MDA, and MAGE remained
基金supported by National Key R&D Program of China (2023YFB3608904)the National Natural Science Foundation of China (62004106, 62274097, 21835003, 62005126)+7 种基金the Natural Science Foundation of Jiangsu Province (BE2019120,BK20210601)the Foundation of Key Laboratory of Flexible Electronics of Zhejiang Province (2023FE002)Program for Jiangsu Specially-Appointed Professors (RK030STP15001)the Excellent Scientific and Technological Innovative Teams of Jiangsu Higher Education Institutions (TJ217038)the Six Talent Peaks Project of Jiangsu Province (TD-XCL-009)the 333 Project of Jiangsu Province (BRA2017402)the Project of State Key Laboratory of Organic Electronics and Information Displays,NJUPT (GZR2023-010016)Natural Science Foundation of NJUPT (NY223079)。
文摘Covalent organic frameworks(COFs) are attractive porous crystalline materials with extremely high stability, easy functionalization, and open channels, which are expected to be unique ion conductors/transporters in lithium ion batteries(LIBs). Despite recent advances, low ion conductivity and low transference number, resulting in low charging/discharging rate, low energy density, and short battery life, are the main issues that limit their direct application as solid electrolytes in LIBs. Here, we designed and synthesized a novel polyimide COF, namely, TAPA-PDI-COF, with abundant C=O groups, which has been successfully employed as high-performance solid electrolytes by doping TAPA-PDI-COF and succinonitrile(SN). Both the well-defined nanochannels of COFs and SN confined in the well-aligned channels restricted the free migration of anions, while C=O on COFs and CN groups of SN enhanced Li^(+) transport, thus achieving a high ion conductivity of 0.102 m S cm^(-1)at 80 °C and a high lithium-ion transference number of 0.855 at room temperature. According to density functional theory(DFT)calculations, Li-ion migration mainly adopted in-plane transport rather than the axial pathway, which may be due to the shorter hopping distances in the planar pathway. The results suggest an effective strategy for the design and development of all-solidstate ionic conductors for achieving high-performance LIBs.
基金supported by grants from National Natural Science Foundation of China(82122009,82170605,81873573 and 81970515)Guangdong Natural Science Funds for Distinguished Young Scholar(2019B151502013,China)。
文摘Chronic alcohol consumption causes liver steatosis,cell death,and inflammation.Melatonin(MLT)is reported to alleviate alcoholic liver disease(ALD)-induced injury.However,its direct regulating targets in hepatocytes are not fully understood.In the current study,a cell-based screening model and a chronic ethanol-fed mice ALD model were used to test the protective mechanisms of MLT.MLT ameliorated ethanol-induced hepatocyte injury in both cell and animal models(optimal doses of 10μmol/L and 5 mg/kg,respectively),including lowered liver steatosis,cell death,and inflammation.RNA-seq analysis and loss-of-function studies in AML-12 cells revealed that telomerase reverse transcriptase(TERT)was a key downstream effector of MLT.Biophysical assay found that epidermal growth factor receptor(EGFR)on the hepatocyte surface was a direct binding and regulating target of MLT.Liver specific knock-down of Tert or Egfr in the ALD mice model impaired MLT-mediated liver protection,partly through the regulation of nuclear brahma-related gene-1(BRG1).Long-term administration(90 days)of MLT in healthy mice did not cause evident adverse effect.In conclusion,MLT is an efficacious and safe agent for ALD alleviation.Its direct regulating target in hepatocytes is EGFR and downstream BRG1-TERT axis.MLT might be used as a complimentary agent for alcoholics.
基金supported by the National Key R&D Program of China(No.2021YFE0113700)the National Natural Science Foundation of China(No.32122074)+1 种基金the Fundamental Research Funds for the Central Universities(No.2021FZZX001-31)the Programme for High-Level Talents Cultivation of Zhejiang University,and the Strategic Research on‘Plant Microbiome and Agroecosystem Health'(No.2020ZL008,Cao Guangbiao High Science and Technology Foundationof Zhejiang University),China。
文摘Seed-borne bacterial pathogens cause severe yield loss and biotoxin contamination in rice,leading to increasing concern on the global food supply and environmental safety.Plant native microbes play an important role in defending against diseases,but their actions are often influ-enced by the chemical fungicides applied in the field.Here,Bacillus licheniformis mmj was isolated from rice spikelet,which uniquely showed not only fungicide-responsiveness but also broad-spectrum antimicrobial activity against major rice bacterial pathogens including Xanthomonas oryzae pv.oryzae,Burkholderia plantari and Burkholderia glumae.To understand the hallmark underlying the environmental adaptation and anti-microbial activity of B.licheniformis mmj,the genome sequence was determined by SMRT and subjected to bioinformatics analysis.Genome sequence analysis enabled the identification of a set of antimicrobial-resistance and antibacterial activity genes together with an array of harsh environment-adaptive genes.Moreover,B.licheniformis mmj metabolites were analyzed with gas chromatography coupled to triple quadrupole mass spectrometry,and the volatile components that were linked with the antimicrobial activity were preliminarily profiled.Collectively,the present findings reveal the genomic and metabolic landscapes underlying fungicide-responsive B.licheniformis,which offers a new opportunity to design harsh environment-adaptive biopesticides to cope with prevalent bacterial phytopathogens.
基金supported by the Natural Science Foundation of China(60008001)the Natural Science Foundation of Zhejiang Province(300297).
文摘Incompletely closed glumes, germination on panicle and disease are three important factors causing poor seed quality of hybrid rice. To determine how many and which categories should be classified to meet the demand for seed in rice production, the effects of various degrees of incompletely closed glumes, germination on panicle and disease on germination percentage at the harvest and after storage for six months were studied by standard germination percentage test. Six categories of seeds with germ (germinated seeds), severe disease, incompletely closed glumes, spot disease, fine fissure and normal seeds were inspected and then treated separately. Images of the five hybrid rice seed (Jinyou 402, Shanyou 10, Zhongyou 27, Jiayou 99 and Ⅱ you 3207) were acquired with a self-developed machine vision system. Each image could be processed to get the feature values of seed region such as length, width, ratio of length to width, area, solidity and hue. Then all the images of normal seeds were calculated to draw the feature value ranges of each hybrid rice variety. Finally, an image information base that stores typical images and related feature values of each variety was established. This image information base can help us to identify the classification limit of characteristics, and provide the reference of the threshold selection. The management of large numbers of pictures and the addition of new varieties have been supported. The research laid a foundation for extracting image features of hybrid rice seed, which is a key approach to future quality inspection with machine vision.
基金supported by Open Fund of State Key Laboratory of Digital Manufacturing Equipment and Technology of China (Grant No.DMETKF2022015).
文摘To enhance the efficiency of system modeling and optimization in the conceptual design stage of satellite parameters,a system modeling and optimization method based on System Modeling Language and Co-evolutionary Algorithm is proposed.At first,the objectives of satellite mission and optimization problems are clarified,and a design matrix of discipline structure is constructed to process the coupling relationship of design variables and constraints of the orbit,payload,power and quality disciplines.In order to solve the problem of increasing nonlinearity and coupling between these disciplines while using a standard collaborative optimization algorithm,an improved genetic algorithm is proposed and applied to system-level and discipline-level models.Finally,the CO model of satellite parameters is solved through the collaborative simulation of Cameo Systems Modeler(CSM)and MATLAB.The result obtained shows that the method proposed in this paper for the conceptual design phase of satellite parameters is efficient and feasible.It can shorten the project cycle effectively and additionally provide a reference for the optimal design of other complex projects.
基金financial support from the National Natural Science Foundation of China (21835003, 91833304,21422402, 62274097, 21674050, 62004106)the National Key Basic Research Program of China (2014CB648300,2017YFB0404501)+11 种基金the Natural Science Foundation of Jiangsu Province (BE2019120, BK20160888)Program for Jiangsu Specially-Appointed Professor (RK030STP15001)the Six Talent Peaks Project of Jiangsu Province (TD-XCL-009)the333 Project of Jiangsu Province (BRA2017402)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (20KJB140005)China Postdoctoral Science Foundation (2020M671553)the NUPT"1311 Project"and Scientific Foundation (NY217169, NY215062, NY215107,NY217087)the Leading Talent of Technological Innovation of National Ten-Thousands Talents Program of Chinathe Excellent Scientific and Technological Innovative Teams of Jiangsu Higher Education Institutions (TJ217038)the Postgraduate Research&Practice Innovation Program of Jiangsu Province (SJCX21-0297)the Synergetic Innovation Center for Organic Electronics and Information Displaysthe Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘Wavelength-tunable organic semiconductor lasers based on mechanically stretchable polydimethylsiloxane (PDMS) gratings were developed. The intrinsic stretchability of PDMS was explored to modulate the period of the distributed feedback gratings for fine tuning the lasing wavelength. Notably, elastic lasers based on three typical light-emitting molecules show com-parable lasing threshold values analogous to rigid devices and a continuous wavelength tunability of about 10 nm by mechanic-al stretching. In addition, the stretchability provides a simple solution for dynamically tuning the lasing wavelength in a spec-tral range that is challenging to achieve for inorganic counterparts. Our work has provided a simple and efficient method of fab-ricating tunable organic lasers that depend on stretchable distributed feedback gratings, demonstrating a significant step in the advancement of flexible organic optoelectronic devices.
基金Supported by the National Natural Science Foundation of China
文摘A tilt-correction adaptive optical system installed on the 430 mm Solar Telescope of Nanjing University has been put in operation. It consists of a tip-tilt mirror, a correlation tracker and an imaging CCD camera. An absolute difference algorithm is used for detecting image motion in the correlation tracker. The sampling frequency of the system is 419 Hz. We give a description of the system's configuration, an analysis of its performance and a report of our observational results. A residual jitter of 0.14 arcsec has been achieved. The error rejection bandwidth of the system can be adjusted in the range 5-28 Hz according to the beacon size and the strength of atmospheric turbulence.
文摘Background: The purpose of this study was to analyze the effects of all clinical characteristics on the overall survival time, in order to provide a basis for determining the prognostic factor of patients with pancreatic cancer. Methods: A total of 103 pancreatic cancer patients were admitted to the Department of Radiotherapy and Chemotherapy of the Ruijin Hospital, Shanghai Jiaotong University School of Medicine, between January 2002 and December 2012. There were 68 men and 35 women; the median age was 62 years. Diagnoses of pancreatic cancer in all patients were confirmed by histopathology, cytology, or clinical diagnosis. The Kaplan-Meier method was performed to calculate the overall survival rate. The log-rank method was used to examine the univariate analysis. The Cox regression model was performed for multivariate analysis. Results: The median survival time was 293 days, the 1-, 2-, and 3-year survival rates were 27.18%, 5.83%, and 1.94%, respectively. Cox regression analysis revealed that age (P=0.015), Karnofsky performance status (PS) (P=0.002), surgical types (P〈0.001), and platelet counts (P〈0.001) were independent prognostic factors affecting the overall survival of patients with pancreatic cancer. Conclusions" Pancreatic cancer had a poor prognosis, the general physical condition, age, the availability of radical surgery, and platelet counts were factors influencing the overall survival of patients with pancreatic cancer.
基金supported by the National Key Scientific Research Project(2017YFC1001903)Provincial and Ministerial Level Projects(cstc2016shmstzx10006)the Guizhou Provincial Science&Technology Program(QKHZC[2020]4Y154).
文摘Fizzy-related protein homolog 1 (FZR1) mainly functions as a specific activator of the anaphase-promotingcomplex/cyclosome (APC/C) in the cell cycle and controls the G0 and G1 phases of the cell cycle. We highlightrecent work that has studied the role of FZR1 in tumorigenesis, growth, differentiation, and genome stability throughcell-cycle control. We summarize the current state of knowledge regarding FZR1 structure, function, and the distinctways of APC/C dysregulation in solid tumors and hematologic malignancies. We also discuss novel approaches fortargeting the FZR1 as a cancer therapy and research area for future work.
基金supported by the Open Foundation of Key Laboratory of Ecohydrology in Inland River Basin, Chinese Academy of Sciences and National Nature Science Foundation of China (No. 9112502)The Coupling and Modeling of Eco-hydrological Processes in the Upper Reaches of Heihe River (No. 91225302)+1 种基金Research of Eco-hydrological Response Units in Heihe River Basin Based on the Method of Concept Lattice (No. 41240002)System Behaviors and Regulation of Ecohydrological Processes in the Middle and Lower Heihe River Basin (91225301)
文摘All rivers in the Hexi inland region of Gansu Province, China, originate from the northern slope of the Qilian Mountains. They are located in the southern portion of the region and respectively belong to the three large river systems from east to west, the Shiyang, Heihe and Shule river basins. These rivers are supplied by precipitation, snowmelt and ice-melt runoff from the Qilian Mountain area. Therefore, changes of precipitation and temperature in the upstream watersheds of these rivers have an important effect on changes of mountainous runoff and reasonable utilization of water resources in this region. For this reason, the Qilian Mountain area, upstream watersheds and runoff forming areas of these rivers are chosen as the study area. The change characteristics and variation trend of temperature and precipitation in this area under the backdrop of global warming axe analyzed based on observa- tional data of relational weather and hydrologic stations in the area. Results show that temperatures in the upriver mountain areas of these three large river basins have been increasing, although the increasing degree is differentially affected by global warming. The rising extent of annual and seasonal temperatures in the upstream mountain area of the Shule river basin located in the west- em Qilian Mountains, were all largest over the past 50 years. Precipitation in the upstream mountain areas of Hexi region' three river basins located respectively in the western, middle and eastern Qilian Mountains have been presenting an increasing trend to varying degrees as a whole for more than 50 years. This means that climate in the upstream mountain areas of Hexi region' three river basins are becoming increasingly warmer and moister over the past 50 years, which will be very good for the ecological en- vironment and agricultural production in the region.
基金the financial assistance of the National Natural Science Foundation of China(GrantNo.71110107028)CAS(Grant No.KZZD-EW-06-02)
文摘Drawing on a survey of106 secondary vocational schools and 7309 students in two provinces of China, this descriptive paper assesses whether vocational schooling is measuring up to government benchmarks for quality and whether poor students are able to access quality schools. We find that secondary vocational schools have met government benchmarks for teacher qualification and training, student opportunities forpractical training and adequate facilities. Furthermore, poor students access schools of similar quality to non-poor students, even though 34percent of poor students do not receive financial aid. We conclude that recent policies are successfully ensuring secondary vocational school quality and equity of access to school quality between poor and non-poor students. However, financial aid policies should be re-examined, such that poor students receive sufficient coverage. Moreover, given that input-based measures only proxy school quality, the government should consider holding schools accountable for outcomes such as student learning.
基金supported by grants from National Natural Science Foundation of China(Nos.81701014,81801310,31700076)the Basic Research of Natural Science Project funded by the Department of Science and Technology of Shaanxi Province(No.2017JM8038)the Science and Technology Project funded by the Science and Technology Bureau of Weiyang District,Xi’an city(No.201846)。
文摘In this study, we employed a nonthermal atmospheric pressure plasma(NTAPP) jet to evaluate the effect of plasma treatment on the durability of resin–dentin bonding under a thermocycling challenge. Furthermore, we assessed the degradation resistance of plasma-treated collagen under a sodium hypochlorite(NaClO) challenge. We assessed the beneficial effect of NTAPP treatment on the acid-etched dentin–bonding interface by testing the micro-tensile bond strength and examining the morphology. We found that the immediate bonding strength of the dentin significantly increased after NTAPP treatment. Compared with the control group, NTAPP resulted in a more prominent effect on the bonding durability of the dentin–adhesive interface after treatment for 5 or 10 s. Simultaneously, the mechanical strength of dentin collagen under the NaClO challenge was improved. Our results indicate that, in optimal conditions, NTAPP could be a promising method to protect dentin collagen and to improve the bonding durability between dentin and etch-and-rinse adhesives.