527 research outputs found

    Rural Labor Absorption Efficiency in Urban Areas under Different Urbanization Patterns and Industrial Structures: The Case of China

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    In this paper, we use Data Envelopment Analysis (DEA) to estimate how well China’s urban areas absorb migrant workers under the interaction of urbanization and industrialization. We applied an output-oriented BCC model to evaluate provincial and regional rural labor absorption efficiency in mainland China. It appears that 4 out of 31 provinces and municipals are efficient, and 2 out of 8 economic regions are efficient in absorbing migrant workers. In the southern and eastern parts of China, urban labor absorption efficiency is higher compared with the western and northern parts of China. Different urbanization patterns and industrial development strategies should be adopted in different economic areas to enhance labor absorption ability in these areas. Urban areas in many parts of China still have potential to accommodate rural migrant workers. The inter-regional flow of production factors would affect urban labor absorption efficiency.rural labor absorption in urban areas, urbanization, industry structure, DEA

    Universal scaling of strange particle pTp_{\rm T} spectra in pp collisions

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    As a complementary study to that performed on the transverse momentum (pTp_{\rm T}) spectra of charged pions, kaons and protons in proton-proton (pp) collisions at LHC energies 0.9, 2.76 and 7 TeV, we present a scaling behaviour in the pTp_{\rm T} spectra of strange particles (KS0K_{S}^{0}, Λ\rm \Lambda, Ξ\rm \Xi and ϕ\phi) at these three energies. This scaling behaviour is exhibited when the spectra are expressed in a suitable scaling variable z=pT/Kz=p_{\rm T}/K, where the scaling parameter KK is determined by the quality factor method and increases with the center of mass energy (s\sqrt{s}). The rates at which KK increases with lns\mathrm{ln}\sqrt{s} for these strange particles are found to be identical within errors. In the framework of the colour string percolation model, we argue that these strange particles are produced through the decay of clusters that are formed by the colour strings overlapping. We observe that the strange mesons and baryons are produced from clusters with different size distributions, while the strange mesons (baryons) KS0K_{S}^{0} and ϕ\phi (Λ\rm \Lambda and Ξ\rm \Xi) originate from clusters with the same size distributions. The cluster's size distributions for strange mesons are more dispersed than those for strange baryons. The scaling behaviour of the pTp_{\rm T} spectra for these strange particles can be explained by the colour string percolation model in a quantitative way.Comment: 8 pages, 10 figures, accepted by EPJ

    Triple condensate halo from water droplets impacting on cold surfaces

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    Understanding the dynamics in the deposition of water droplets onto solid surfaces is of importance from both fundamental and practical viewpoints. While the deposition of a water droplet onto a heated surface is extensively studied, the characteristics of depositing a droplet onto a cold surface and the phenomena leading to such behavior remain elusive. Here we report the formation of a triple condensate halo observed during the deposition of a water droplet onto a cold surface, due to the interplay between droplet impact dynamics and vapor diffusion. Two subsequent condensation stages occur during the droplet spreading and cooling processes, engendering this unique condensate halo with three distinctive bands. We further proposed a scaling model to interpret the size of each band, and the model is validated by the experiments of droplets with different impact velocity and varying substrate temperature. Our experimental and theoretical investigation of the droplet impact dynamics and the associated condensation unravels the mass and heat transfer among droplet, vapor and substrate, offer a new sight for designing of heat exchange devices

    Effect of the combination of percutaneous transluminal angioplasty and pharmacological thrombolysis on hemodialysis patients

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    Purpose: To examine the efficacy of percutaneous transluminal angioplasty (PTA), combined withpharmacologic thrombolysis (PT) on thrombosis of autologous arteriovenous fistulas (AVFs),inflammatory factors, and β2 microglobulin (β2-MG) levels in hemodialysis patients.Methods: Seventy-eight patients with AVF thrombosis allocated randomly into a control group (CG) received PTA, and a study group (SG) received PTA combined with PT (n = 39 in each). The patency, vascular condition, inflammatory factors, viz, interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP)), β2-MG levels, vascular-related factors (VEGF-A and MCP-1), complications, and quality of life were determined.Results: At three and six months after surgery, t SG exhibited a higher vascular patency than CG (p <0.05). Serum levels of IL-6, hs-CRP, β2-MG, VEGF-A, and MCP-1 of t SG were lower than those of CG(p < 0.05). The SG showed higher cross-sectional area, inner diameter at the site of fistula, and better quality of life scores than CG (p < 0.05).Conclusion: The combination of PTA and PT enhances efficacy, increases vascular patency, reduces inflammatory response, lowers the level of β2-MG, and improves quality of life in patients with AVFs without increasing complications. Thus, the combination treatment has potentials for the management of hemodialysis patients

    Spatiotemporal assessment of PM<sub>2.5</sub>-related economic losses from health impacts during 2014–2016 in China

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    Background: Particulate air pollution, especially PM2.5, is highly correlated with various adverse health impacts and, ultimately, economic losses for society, however, few studies have undertaken a spatiotemporal assessment of PM2.5-related economic losses from health impacts covering all of the main cities in China. Methods: PM2.5 concentration data were retrieved for 190 Chinese cities for the period 2014&ndash;2016. We used a log-linear exposure&ndash;response model and monetary valuation methods, such as value of a statistical life (VSL), amended human capital (AHC), and cost of illness to evaluate PM2.5-related economic losses from health impacts at the city level. In addition, Monte Carlo simulation was used to analyze uncertainty. Results: The average economic loss was 0.3% (AHC) to 1% (VSL) of the total gross domestic product (GDP) of 190 Chinese cities from 2014 to 2016. Overall, China experienced a downward trend in total economic losses over the three-year period, but the Beijing&ndash;Tianjin&ndash;Hebei, Shandong Peninsula, Yangtze River Delta, and Chengdu-Chongqing regions experienced greater annual economic losses. Conclusions: Exploration of spatiotemporal variations in PM2.5-related economic losses from long-term health impacts could provide new information for policymakers regarding priority areas for PM2.5 pollution prevention and control in China

    Structural Basis of Ligand Interaction with Atypical Chemokine Receptor 3

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    Chemokines drive cell migration through their interactions with seven-transmembrane (7TM) chemokine receptors on cell surfaces. The atypical chemokine receptor 3 (ACKR3) binds chemokines CXCL11 and CXCL12 and signals exclusively through β-arrestin-mediated pathways, without activating canonical G-protein signalling. This receptor is upregulated in numerous cancers making it a potential drug target. Here we collected over 100 distinct structural probes from radiolytic footprinting, disulfide trapping, and mutagenesis to map the structures of ACKR3:CXCL12 and ACKR3:small-molecule complexes, including dynamic regions that proved unresolvable by X-ray crystallography in homologous receptors. The data are integrated with molecular modelling to produce complete and cohesive experimentally driven models that confirm and expand on the existing knowledge of the architecture of receptor:chemokine and receptor:small-molecule complexes. Additionally, we detected and characterized ligand-induced conformational changes in the transmembrane and intracellular regions of ACKR3 that elucidate fundamental structural elements of agonism in this atypical receptor

    Research on institutional contradiction and legitimacy crisis of internet car-hailing platform with the Grounded Theory

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    Based on the case of DiDi travel platform event, we used the grounded theory to analyze the legitimacy crisis occurrence mechanism of internet car-hailing platforms organizational field. We found that, the institutional contradiction between public welfare logic and profit logic in the process of DiDi’s Institutional Entrepreneurship leads to the legitimacy crisis; the crisis event causes the government\u27s supervision, media attention and consumer resistance, which ultimately leads to the deterioration and spillover of legitimacy crisis from DiDi to the whole internet car-hailing platforms organizational field

    Energy Efficient Indirect Evaporative Air Cooling

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    An energy-saving and environmentally friendly air-conditioning method has been proposed. The key component is a novel indirect evaporative heat exchanger (IEHX) based on the M-cycle. In this design, the compact IEHX is able to produce sub-wet-bulb cooling and reduce the air temperature approaching dew-point temperature. This chapter aims to achieve a fundamental understanding of the novel IEHX. A numerical model has been developed and validated by comparing the simulated outlet air conditions against experimental data. The model showed a good agreement with the experimental findings. Employing the validated numerical model, we have theoretically investigated the heat and mass transfer behavior occurred in the IEHX. The detailed cooling process has been analyzed on the psychrometric chart. In addition, the effects of varying inlet conditions and airflow passage dimensions on the cooling efficiency have been studied. By analyzing the thermal performance of the IEHX, we have provided possible suggestions to improve the performance of the dew-point cooler and enable it to attain higher cooling effectiveness
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