Abstract
The application of industrial robots is considered a significant factor affecting environmental pollution. Selecting industrial wastewater discharge, industrial SO
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emissions and industrial ...soot emissions as the evaluation indicators of environmental pollution, this paper uses the panel data model and mediation effect model to empirically examine the impact of industrial robots on environmental pollution and its mechanisms. The conclusions are as follows: (1) Industrial robots can significantly reduce environmental pollution. (2) Industrial robots can reduce environmental pollution by improving the level of green technology innovation and optimizing the structure of employment skills. (3) With the increase in emissions of industrial wastewater, industrial SO
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, and industrial dust, the impacts generated by industrial robots are exhibiting trends of a “W” shape, gradual intensification, and progressive weakening. (4) Regarding regional heterogeneity, industrial robots in the eastern region have the greatest negative impact on environmental pollution, followed by the central region, and the western region has the least negative impact on environmental pollution. Regarding time heterogeneity, the emission reduction effect of industrial robots after 2013 is greater than that before 2013. Based on the above conclusions, this paper suggests that the Chinese government and enterprises should increase investment in the robot industry. Using industrial robots to drive innovation in green technology and optimize employment skill structures, reducing environmental pollution.
The urban heat island (UHI) effect is becoming more of a concern with the accelerated process of urbanization. However, few studies have examined the effect of urban form on land surface temperature ...(LST) especially from an urban planning perspective. This paper used spatial regression model to investigate the effects of both land use composition and urban form on LST in Wuhan City, China, based on the regulatory planning management unit. Landsat ETM+ image data was used to estimate LST. Land use composition was calculated by impervious surface area proportion, vegetated area proportion, and water proportion, while urban form indicators included sky view factor (SVF), building density, and floor area ratio (FAR). We first tested for spatial autocorrelation of urban LST, which confirmed that a traditional regression method would be invalid. A spatial error model (SEM) was chosen because its parameters were better than a spatial lag model (SLM). The results showed that urban form metrics should be the focus for mitigation efforts of UHI effects. In addition, analysis of the relationship between urban form and UHI effect based on the regulatory planning management unit was helpful for promoting corresponding UHI effect mitigation rules in practice. Finally, the spatial regression model was recommended to be an appropriate method for dealing with problems related to the urban thermal environment. Results suggested that the impact of urbanization on the UHI effect can be mitigated not only by balancing various land use types, but also by optimizing urban form, which is even more effective. This research expands the scientific understanding of effects of urban form on UHI by explicitly analyzing indicators closely related to urban detailed planning at the level of regulatory planning management unit. In addition, it may provide important insights and effective regulation measures for urban planners to mitigate future UHI effects.
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•Building density is a key indicator in mitigating UHI effect.•Spatial regression is a promising method for dealing with problems related to the urban thermal environment.•Regulatory planning management unit was recommended for analyzing the relationships between urban form and the UHI effect.•Attention should be paid to the influence of urban form on UHI effect in urban planning.
Microplastics are an emerging concern in the marine environment due to their small size; they can be ingested by aquatic organisms, especially filter-feeding organisms, such as oysters. The presence ...of microplastics in seafood may pose a threat to food safety, and there is an urgent need to evaluate the potential risks of microplastics to human health. This study quantified the microplastics in oysters from 17 sites along the coastline of China. Qualitative attributes, such as shape and size, were also determined under a microscope. Additionally, the polymer types were identified using Fourier-Transform Infrared Micro-Spectroscopy (μ-FT-IR). The results showed that the average abundance of microplastics in oyster was 0.62 items/g (wet weight) or 2.93 items/individual. Additionally, 84% of the sampled oysters had inhaled microplastics, indicating the high prevalence of microplastic pollution in different coastal areas of China. Fibers were the most common shape (60.67%), and the most common size was <1500 μm, accounting for 81.89% of the total microplastics. The μ-FT-IR analysis identified eight different polymers, and the main polymeric types of microplastics were cellophane (CP), polyethylene (PE) and polyethylene terephthalate (PET). Our results suggest the widespread prevalence of microplastics in cultured oysters from different coastal areas of China with similar or lower abundances than other countries. In addition, our results exhibited regional characteristics of high microplastics abundance in southern coastal area of China and low microplastics abundance in northern China. Further investigations are warranted to examine microplastics contamination in other seafood species from different geographical sites in coastal area of China.
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•Microplastic uptake was identified in cultured oysters from 17 cites of China.•Eighty-four percent of sampled oysters had inhaled microplastics.•The average microplastics abundance was 0.62 items/g (ww) or 2.93 items/individual.•The most common polymeric types of microplastics in oysters were CP, PE and PET.
The pre-metastatic niche educated by primary tumor-derived elements contributes to cancer metastasis. However, the role of host stromal cells in metastatic niche formation and organ-specific ...metastatic tropism is not clearly defined. Here, we demonstrate that lung epithelial cells are critical for initiating neutrophil recruitment and lung metastatic niche formation by sensing tumor exosomal RNAs via Toll-like receptor 3 (TLR3). TLR3-deficient mice show reduced lung metastasis in the spontaneous metastatic models. Mechanistically, primary tumor-derived exosomal RNAs, which are enriched in small nuclear RNAs, activate TLR3 in lung epithelial cells, consequently inducing chemokine secretion in the lung and promoting neutrophil recruitment. Identification of metastatic axis of tumor exosomal RNAs and host lung epithelial cell TLR3 activation provides potential targets to control cancer metastasis to the lung.
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•TLR3 deficiency reduces lung metastasis in the spontaneous cancer metastatic models•Host TLR3 promotes lung pre-metastatic niche formation via neutrophil recruitment•Tumor exosomal RNAs activate alveolar epithelial TLR3 to induce chemokines•High TLR3 level and neutrophil infiltration in lung cancer predict poor prognosis
Liu et al. demonstrate that TLR3 in host alveolar epithelial cells is critical for neutrophil recruitment and lung pre-metastatic niche formation. Mechanistically, small nuclear RNAs from primary tumor-derived exosomes activate TLR3, which leads to chemokine secretion and neutrophil infiltration.
Due to the close links between quality of life standards and level of regional development, it is important to gain an improved understanding of the factors that contribute to unequal spatial ...accessibility of medical and health services in China. This study analyzed 2859 counties using the average shortest distance traveled from settlements to medical facilities to calculate spatial accessibility. The Theil index at three levels (three partitions, eight economic zones and provinces) was used to assess the inequality between regions. Then, a method of spatial autocorrelation was used to assess the spatial agglomeration characteristics of spatial accessibility. To explore the underlying reasons for the imbalance in spatial accessibility, a total of eight indicators in three aspects (nature, society, and economy) were collected and geographically weighted regression (GWR) was employed to investigate spatial heterogeneity. We observed marked disparities in spatial accessibility to medical facilities at the national level. In particular, there appears to be improved spatial accessibility and lesser regional inequality in eastern and central regions as opposed to western Chinese regions; in coastal regions instead of inland regions; and in municipalities such as Beijing, Tianjin, and Shanghai, but not in other provinces and autonomous regions. Besides, significant global autocorrelation and obvious clusters were revealed in a spatial pattern analysis. A wide range of hot-spot areas (clusters of poor spatial accessibility) mainly concentrated in Tibet and other areas with complex terrain and lagging social and economic development. A number of cold-spot areas (clusters of good spatial accessibility) mostly scattered in built-up areas especially municipalities and well-developed urban agglomeration such as the Yangtze River Delta, the Pearl River Delta, and the Wuhan 1 + 8 city circle. Furthermore, the relationships between influencing factors and spatial accessibility were also investigated. The influence of altitude on spatial accessibility gradually decreased from the West to the East, while the influence of slope decreased from the South to the North with prominent provinces of Qinghai and Gansu. Population density exerted a higher impact on the distance in the southwest region whereas the urbanization rate influenced the northeast and southeast coastal region more intensively. In contrast, the pattern of educational level was relatively discrete. The influencing pattern of economic factors in both per area GDP and tertiary industry output share of accessibility showed apparent regional characteristics in the southeast coastal areas, as well as in the northwestern and northeastern parts. Outcomes from this study can be used to provide important information to aid policy making, while also facilitating future research aimed at improving the understanding of equality and sustainable development of medical facilities.
•This study provides data of medical facility accessibility for 2859 counties in China.•Disparities were found in spatial accessibility to medical facilities at three scales.•A significant global autocorrelation and obvious clusters were revealed.•Prominent counties with significant disparity to their neighbors were identified.•The aspects nature, society, and economy and eight influencing factors were analyzed.
•An assessment is carried out on the relationships between urbanization and ecosystem services.•There is a close interrelationship between ecosystem services and urbanization.•The response of ...different ecosystem services to urbanization varies.•The interaction between urbanization and ecosystem services is significantly influenced by scale effects.
Rapid urbanization has brought about continuous urban expansion, which has put enormous pressure on ecosystems. In this paper, we take both temporal and spatial dimensions into account to discuss the interaction between various ecological services (ESs) and urbanization in Shandong Province based on data at different scales. We utilize the InVEST model for quantifying ESs indicators. Pearson correlation analysis and geographically weighted regression were used to investigate the relationship with the four urbanization indicators. The results of the study indicate that with the development of urbanization, the regulating and supporting services of land in Shandong province show an upward trend. In contrast, the supply services show a downward trend. There is a significant correlation between ESs and urbanization (p < 0.05). Regarding sub-indicators, water yield (WY) increases with urbanization, and carbon sequestration (CS)/grain providing (GP)/habitat quality (HQ) are negatively correlated with the four urbanization indicators. Geographically weighted regressions show that the results fit well only when we choose counties as the study scale, and there is a clear tendency of aggregation. In summary, this paper clarifies the spatio-temporal variation of ESs and the response to urbanization, which provides an effective reference for ecosystem management in Shandong Province. This paper suggests that the government should formulate targeted policies for ecosystem service management in different regions and make appropriate dynamic adjustments to the spatial scale of policy formulation.
The mechanism and factors influencing nitrogen loss in the Zhoucun reservoir were explored during the spring. The results showed that the nitrate and total nitrogen concentration decreased from ...1.84 ± 0.01 mg/L and 2.34 ± 0.06 mg/L to 0.06 ± 0.01 mg/L and 0.48 ± 0.09 mg/L, respectively. Meanwhile, the nitrate and total nitrogen removal rate reached 97.02% ± 0.25 and 79.38% ± 3.32, respectively. Moreover, the abundance of nirS gene and aerobic denitrification bacteria increased from 1.04–3.38 × 103 copies/mL and 0.71 ± 0.22 × 102 cfu/mL to 5.36–5.81 × 103 copies/mL and 8.64 ± 2.08 × 103 cfu/mL, respectively. The low MW fractions of DOM (<5 kDa) increased from 0.94 ± 0.02 mg/L in February to 1.51 ± 0.09 mg/L in April. E3/E4 and absorption spectral slope ratio (SR) showed that fulvic acid accounted for the main proportion with autochthonous characteristics. These findings were consistent with the fluorescence components and fluorescence characteristic indices based on EEM-PARAFAC. Meanwhile, the microbial metabolism activity increased significantly from February to April, which contributed to the cycle of nutrients within the reservoir water system. Moreover, the abundance of the bacterial species involved in denitrification (Exiguobacterium, Brevundimonas, Deinococcus, Paracoccus, and Pseudomonas) increased significantly. The relative abundance of KOs related to nitrogen metabolism, were initially increased and then decreased. Specifically, K02567 (napA) represented the main proportion of KOs related to denitrification. The abundance of napA-type denitrifying bacteria (Dechloromonas, Pseudomonas, Azospira, Rhodopseudomonas, Aeromonas, Zobellella, Sulfuritalea, Bradyrhizobium, Achromobacter, Enterobacter, Thauera, and Magnetospirillum) increased significantly during the period of nitrogen loss. Furthermore, the levels of nitrate, T, DO, and AWCD were the most important factors affecting the N-functional bacteria composition. The systematic investigation of the nitrogen loss would provide a theoretical foundation for the remediation of the water reservoir via aerobic denitrification in the future.
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•Microbial aerobic denitrification dominates nitrogen loss of water column in the spring.•The abundance of nirS and aerobic denitrification bacteria increased obviously.•The abundance of N-functional bacteria and napA-type denitrification bacteria both exhibited obvious increase process.
An effective structural doping approach has been described to modify the photoelectrochemical properties of g-C3N4 by doping with nonmetal (sulfur or phosphorus) impurities. Here, the substitutional ...and interstitial doped models of g-C3N4 systems were constructed with different doped sites, and then their dopant formation energies and electronic properties were performed to study the stability and visible-light photoactivity using first-principles density functional theory, respectively. Our results have identified that an S atom preferentially substitutes for the edge N atom of g-C3N4; however, a P atom preferentially situates the interstitial sites of in-planar of g-C3N4. Furthermore, it is demonstrated that the doping with nonmetal impurities reduces the energy gap to enhance the visible-light absorption of g-C3N4. The increased dispersion of the contour distribution of the HOMO and LUMO brought by doping facilitates the enhancement of the carrier mobility, while the noncoplanar HOMO and LUMO favor the separation of photogenerated electron–hole pairs. Especially, P interstitial doping shows a prominent potential due to the appearance of a new channel for carrier migration. It should be pointed out that the proper doping form should be controlled, so that reasonable photoelectrochemical properties can be achieved.
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