93 research outputs found
Effects of human capital, family background and social network on occupational mobility in contemporary urban China
The Chinese market transition has provided new opportunities for individuals to improve social status. In contemporary urban China, do people have equal access to opportunities to obtain occupational status? Following theories of human capital, social network and market transition, this study uses a dataset of the 2003 China General Social Survey and interviews, to explore different effects of human capital, family background and social network on occupational mobility from a perspective of work sector change.
The first major finding is that the returns for education were highest for those whose first and second occupations were in the state sector. Work experience and party membership were significant only for workers remaining in the state sector and human capital was often considered equal to work ability. In the private sector, occupational status depended on recognition of the ability to work. Secondly, family background was meaningful for workers transferring within both sectors. In the state sector, the effects were mainly through the use of fathers’ political power to make occupational promotion whereas in the private sector, it came down to economic support or information transmission. Thirdly, social network was significant in the form of strong ties if workers stayed in the state sector or transferred there from the private sector. It mainly took the form of job information for those staying in or transferring to the private sector. And last, education significantly affected income for all groups but with the highest returns for stayers.
I conclude that for one thing, human capital, family background and social network exert markedly different effects on occupational mobility in four subgroups in contemporary urban China. The use of political power is the main influence of family background and social network, especially for those transferring to the state sector. The institutionalization of occupational promotion based on political power may result in unequal opportunity for job and status mobility and consequently the stagnation of economic and social development.
In order to establish a fair labour market, five policy proposals are made related to promotion of a market-oriented economy, disclosure of information in the labour market, law regulation, reform of distribution of socioeconomic benefits, and political system reform
Efficient Parallel Implementation of Active Appearance Model Fitting Algorithm on GPU
The active appearance model (AAM) is one of the most powerful model-based object detecting and tracking methods which has been widely used in various situations. However, the high-dimensional texture representation causes very time-consuming computations, which makes the AAM difficult to apply to real-time systems. The emergence of modern graphics processing units (GPUs) that feature a many-core, fine-grained parallel architecture provides new and promising solutions to overcome the computational challenge. In this paper, we propose an efficient parallel implementation of the AAM fitting algorithm on GPUs. Our design idea is fine grain parallelism in which we distribute the texture data of the AAM, in pixels, to thousands of parallel GPU threads for processing, which makes the algorithm fit better into the GPU architecture. We implement our algorithm using the compute unified device architecture (CUDA) on the Nvidia’s GTX 650 GPU, which has the latest Kepler architecture. To compare the performance of our algorithm with different data sizes, we built sixteen face AAM models of different dimensional textures. The experiment results show that our parallel AAM fitting algorithm can achieve real-time performance for videos even on very high-dimensional textures
Pathologically Activated Neuroprotection via Uncompetitive Blockade of \u3cem\u3eN\u3c/em\u3e-Methyl-d-aspartate Receptors with Fast Off-rate by Novel Multifunctional Dimer Bis(propyl)-cognitin
Uncompetitive N-methyl-d-aspartate (NMDA) receptor antagonists with fast off-rate (UFO) may represent promising drug candidates for various neurodegenerative disorders. In this study, we report that bis(propyl)-cognitin, a novel dimeric acetylcholinesterase inhibitor and Îł-aminobutyric acid subtype A receptor antagonist, is such an antagonist of NMDA receptors. In cultured rat hippocampal neurons, we demonstrated that bis(propyl)-cognitin voltage-dependently, selectively, and moderately inhibited NMDA-activated currents. The inhibitory effects of bis(propyl)-cognitin increased with the rise in NMDA and glycine concentrations. Kinetics analysis showed that the inhibition was of fast onset and offset with an off-rate time constant of 1.9 s. Molecular docking simulations showed moderate hydrophobic interaction between bis(propyl)-cognitin and the MK-801 binding region in the ion channel pore of the NMDA receptor. Bis(propyl)-cognitin was further found to compete with [3H]MK-801 with a Ki value of 0.27 ÎĽm, and the mutation of NR1(N616R) significantly reduced its inhibitory potency. Under glutamate-mediated pathological conditions, bis(propyl)-cognitin, in contrast to bis(heptyl)-cognitin, prevented excitotoxicity with increasing effectiveness against escalating levels of glutamate and much more effectively protected against middle cerebral artery occlusion-induced brain damage than did memantine. More interestingly, under NMDA receptor-mediated physiological conditions, bis(propyl)-cognitin enhanced long-term potentiation in hippocampal slices, whereas MK-801 reduced and memantine did not alter this process. These results suggest that bis(propyl)-cognitin is a UFO antagonist of NMDA receptors with moderate affinity, which may provide a pathologically activated therapy for various neurodegenerative disorders associated with NMDA receptor dysregulation
Advancements and future outlook in fundamental research and technological applications for ammonia co-firing with coal
Energy security and the “dual carbon” goals are impacting the global energy industry and supply chains, presenting some urgent needs for the secure, efficient, and green low-carbon transformation of energy and power systems in China. To ensure energy security, the coal-fired power plant will remain an important support for electricity supply security and the integration of renewable energy for a considerable period into the future in China. To achieve carbon neutrality, the energy system is gradually shifting from primarily relying on fossil fuels to primarily relying on renewable energy. However, the intermittency, randomness, and volatility of renewable energy make power system regulation more challenging, highlighting the issues of system balance and security. In this context, the zero-carbon fuels such as ammonia play an indispensable role in dealing with the intermittency of renewable energy. They can serve as carriers for long-term and large-scale energy storage to facilitate the large-scale integration of renewable energy and can also be flexibly used directly in power equipment such as boilers to replace fossil fuels. However, due to the differences in physical and chemical properties between zero-carbon fuels and fossil fuels, some challenges arise in the widespread utilization of ammonia fuel, such as poor flame stability and the generation of nitrogen oxides during combustion. Therefore, based on the feasibility, economy and necessity of ammoniac-coal co-combustion, this paper comprehensively reviews the chemical reaction kinetics, combustion characteristics (ignition, steady combustion) and pollutants characteristics (NOx, fly ash particles and soot) of ammoniac-coal co-combustion, and discusses the scaling laws of burner based on the dimensionless number. The efficient and stable combustion control strategy of existing industrial grade ammonia-coal burners is discussed in detail. The C—N fuel separation, air staged and their joint control technology can effectively reduce NOx emissions. In the future, artificial intelligence, big data and digital twin and other information technologies are integrated. It is expected to provide a scientific support and path reference for the research and development of the next generation of new green power generation system oriented to the dual carbon strategy from the source
Research and application of coal exploration data management method in working face based on GIS
In order to improve the efficiency of dynamic calculation of coal reserves in the mining process of coal working face and enrich the dynamic updated data required in the construction of 3D geological model of working face in intelligent mining, a GIS based coal mining face data management method is proposed through the full analysis and in-depth research on the professional needs, business processes, technical routes and data structure of coal mining face data management. At the data level, the business process of coal exploration data management was optimized, the data structure and storage method of different types of coal exploration data were designed, the coal exploration data sharing and management of mining face based on spatial relational database were realized from using the spatial data organization and management mode. At the presentation level, the interactive management of coal exploration data and graphics was realized based on the domestic geographic information system platform, LongRuanGIS, independently developed from the bottom. At the business level, a drawing algorithm of coal exploration line was proposed to realize the rapid drawing of different coal exploration lines. The data structure, drawing style, drawing method and data management method of coal exploration point were designed to ensure the beautiful mapping of coal exploration data and efficient reuse of data; a method of dynamically updating the geological model of coal mining face by using the data of coal thickness detection was proposed, which enriches the dynamic updating data source of high-precision three-dimensional dynamic geological model of working face. The results of normalization application in many mines show that the management method of coal exploration data based on GIS realizes the unified management and sharing of different types of coal exploration data, realizes the rapid automatic mapping and dynamic updating of coal exploration data and improves the drawing efficiency of coal mine geologists. At the same time, the timely updating of coal exploration data provides convenient and effective data management measures for dynamic calculation of reserves and dynamic updating of high-precision 3D geological model, ensuring the efficient use of coal exploration data in many aspects
Phage vB_PaeS-PAJD-1 Rescues Murine Mastitis Infected With Multidrug-Resistant Pseudomonas aeruginosa
Pseudomonas aeruginosa is a Gram-negative pathogen that causes a variety of infections in humans and animals. Due to the inappropriate use of antibiotics, multi-drug resistant (MDR) P. aeruginosa strains have emerged and are prevailing. In recent years, cow mastitis caused by MDR P. aeruginosa has attracted attention. In this study, a microbial community analysis revealed that P. aeruginosa could be a cause of pathogen-induced cow mastitis. Five MDR P. aeruginosa strains were isolated from milk diagnosed as mastitis positive. To seek an alternative antibacterial agent against MDR, P. aeruginosa, a lytic phage, designated vB_PaeS_PAJD-1 (PAJD-1), was isolated from dairy farm sewage. PAJD-1 was morphologically classified as Siphoviridae and was estimated to be about 57.9 kb. Phage PAJD-1 showed broad host ranges and a strong lytic ability. A one-step growth curve analysis showed a relatively short latency period (20 min) and a relatively high burst size (223 PFU per infected cell). Phage PAJD-1 remained stable over wide temperature and pH ranges. Intramammary-administered PAJD-1 reduced bacterial concentrations and repaired mammary glands in mice with mastitis induced by MDR P. aeruginosa. Furthermore, the cell wall hydrolase (termed endolysin) from phage PAJD-1 exhibited a strong bacteriolytic and a wide antibacterial spectrum against MDR P. aeruginosa. These findings present phage PAJD-1 as a candidate for phagotherapy against MDR P. aeruginosa infection
All-Trans Retinoic Acid Promotes TGF-β-Induced Tregs via Histone Modification but Not DNA Demethylation on Foxp3 Gene Locus
It has been documented all-trans retinoic acid (atRA) promotes the development of TGF-β-induced CD4(+)Foxp3(+) regulatory T cells (iTreg) that play a vital role in the prevention of autoimmune responses, however, molecular mechanisms involved remain elusive. Our objective, therefore, was to determine how atRA promotes the differentiation of iTregs.Addition of atRA to naïve CD4(+)CD25(-) cells stimulated with anti-CD3/CD28 antibodies in the presence of TGF-β not only increased Foxp3(+) iTreg differentiation, but maintained Foxp3 expression through apoptosis inhibition. atRA/TGF-β-treated CD4(+) cells developed complete anergy and displayed increased suppressive activity. Infusion of atRA/TGF-β-treated CD4(+) cells resulted in the greater effects on suppressing symptoms and protecting the survival of chronic GVHD mice with typical lupus-like syndromes than did CD4(+) cells treated with TGF-β alone. atRA did not significantly affect the phosphorylation levels of Smad2/3 and still promoted iTreg differentiation in CD4(+) cells isolated from Smad3 KO and Smad2 conditional KO mice. Conversely, atRA markedly increased ERK1/2 activation, and blockade of ERK1/2 signaling completely abolished the enhanced effects of atRA on Foxp3 expression. Moreover, atRA significantly increased histone methylation and acetylation within the promoter and conserved non-coding DNA sequence (CNS) elements at the Foxp3 gene locus and the recruitment of phosphor-RNA polymerase II, while DNA methylation in the CNS3 was not significantly altered.We have identified the cellular and molecular mechanism(s) by which atRA promotes the development and maintenance of iTregs. These results will help to enhance the quantity and quality of development of iTregs and may provide novel insights into clinical cell therapy for patients with autoimmune diseases and those needing organ transplantation
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