Impact response of lightweight steel foam concrete composite slabs: Experimental, numerical and analytical studies.

This paper presents a study on the low-velocity impact response of lightweight steel foam concrete (LSFC) composite slabs. The LSFC composite slab consisted of a W-shaped steel plate, foam concrete and oriented strand board (OSB). Low-velocity impact tests on the LSFC composite slabs were conducted by employing an ultra-high heavy-duty drop hammer testing machine. The tests revealed the failure mode, impact force and displacement response of LSFC composite slabs. The effects of density and thickness of foam concrete and drop height on the peak impact force and energy absorption ratio were investigated. A finite element (FE) model was set up to predict the impact resistance of the LSFC composite slabs, and a good agreement between simulation and test results was achieved. In addition, an equivalent-single-degree-of-freedom (ESDOF) model was set up to predict the displacement response of the LSFC composite slabs under impact loading.

Associations of chronotype with anxiety, depression and insomnia among general adult population: A cross-sectional study in Hubei, China.

BACKGROUND: The relationship between chronotype and anxiety, depression, and insomnia was inconsistent. We aimed to assess the association between chronotype and mental health and the potential moderating effect of age and socioeconomic status (SES). METHODS: A multi-stage sampling cross-sectional study with 12,544 adults was conducted. Chronotype, anxiety, depression, and insomnia were investigated by 5-item Morning and Evening, 7-item Generalized Anxiety Disorder, 9-item Patient Health, and the 7-item Insomnia Severity Index Questionnaires. Logistic regression was conducted. RESULTS: The predominant chronotype was morning chronotype (69.2 %), followed by 27.6 % intermediate and 3.2 % evening chronotype. The prevalence of anxiety, depression, and insomnia was 0.7 %, 1.9 %, and 9.6 %, respectively. Compared with intermediate chronotype, morning chronotype participants had a lower risk of anxiety (OR = 0.28,95%CI:0.18-0.44), depression (OR = 0.54,95%CI:0.41-0.72) and insomnia (OR = 0.67,95%CI:0.58-0.77), while evening chronotype participants had a higher risk of depression (OR = 1.98,95%CI:1.06-3.71) but not anxiety or insomnia. Interactions between chronotype with age and SES on insomnia (Pinteraction < 0.05) were found. A more profound association between morning chronotype and insomnia was observed in <65 years participants (OR = 0.59,95%CI:0.50-0.71) and those with monthly household income ≥10,000yuan (OR = 0.21,95%CI:0.12-0.35), compared with their counterparts. LIMITATIONS: The cross-sectional design limited causal conclusions. Only adults were included; the findings could not be generalized to children. CONCLUSIONS: The morning chronotype might be protective for anxiety, depression, and insomnia, while the evening chronotype might be a risk factor for depression. Future studies are needed to assess the efficacy of chronotype-focused intervention for mental health. Insomnia prevention efforts should pay more attention to the elderly and those with lower incomes.

Does new-type urbanization curb haze pollution? A case study from China.

The rapid urbanization process has led to a high concentration of population and economic activities in urban space, thus leading to severe environmental pollution. The concept of new-type urbanization has been proposed in China to combat the pollution associated with urbanization. This study analyzes the interaction effect of new-type urbanization with land, industry, and technology on haze pollution, using Chinese provincial-level panel data, and employs a STIRPAT model with interaction terms for empirical testing. The results find that new-type urbanization can significantly reduce the national haze pollution level; meanwhile, the optimization of intensive urban land use level, industrial structure, and technological innovation can interact with it to promote haze reduction, and there is regional heterogeneity. The improvement of intensive urban land use and industrial structure in the central region will significantly enhance the haze reduction effect of new-type urbanization, while the improvement of technological innovation in the west will instead weaken its haze reduction effect, and the interaction in the eastern region is not significant. This research provides a theoretical basis for better implementation of new-type urbanization construction and effective promotion of green and sustainable urban development.

Re-examining the effect of carbon emission trading policy on improving the green innovation of China's enterprises.

China's carbon emission trading (CET) policy guides enterprises to carry out green innovation and address the growing environmental challenges through market-based instruments. However, can CET policy effectively promote enterprises' green innovation? It has become a hot issue. Whether it can play the "Porter effect" is also controversial. We have little research on the effectiveness and heterogeneity of CET policy in China. We obtained the following conclusions from the empirical results: (1) CET policy has clearly promoted green innovation in enterprises, the proportion of green innovation of enterprises increased by 13.43%, and the "weak Porter hypothesis" was tenable. And the results of the research have been tested to be robust and reliable. (2) CET policy plays an obvious role in enhancing the enterprises' green innovation with high-stock enterprise, large-scale enterprise, and state-owned enterprises. (3) Carbon quota auction does not motivate enterprises to improve green innovation; the CET policy under the ex-post allowance allocation of government can better inspire enterprises to undertake green innovation events. (4) The pilot policy of carbon emission trading can increase the introduction of scientific research talents, increase the expenditure of scientific research and development, and improve the net profit margin of enterprise assets, thus directly or indirectly promoting the development of green innovation of enterprises. Overall, the research in this article provides theoretical policy and empirical research for implementing carbon emission trading policy in developing countries and provides theoretical support for how to realize the "double dividend" of environmental protection and enterprises' green innovation competitiveness. Meanwhile, it also provides reference for the national CET to be officially run, and it is instructive to establish a flexible market-based instruments.

Environmental regulation, firms' bargaining power, and firms' total factor productivity: evidence from China.

The relationship between environmental regulation and firms' total factor productivity (TFP) has always been a hot topic in environmental economics, but the conclusions are still mixed. Employing a sample of 14,375 firm-year observations in China from 2010 to 2018, our research explores whether and when environmental regulation could trigger firms, to enhance TFP. The available evidence leads us to cautiously conclude that: (1) Environmental regulation notably improves firms' TFP, the conclusion still holds after alleviating the endogenous problems and a battery of robustness tests. (2) Firms' bargaining power significantly weakens the effect of environmental regulation on firms' TFP. (3) Compared with non-state-owned firms and non-heavy-polluting industries, environmental regulation has a greater impact on state-owned firms and heavy-polluting industries; higher executive compensation does not motivate firms to improve TFP. Compared with firms headquartered in non-provincial capital cities, environmental regulation has a greater impact on firms' TFP in provincial capital cities. Overall, the findings of our research are extremely relevant for the governments, investors, and firms' managers; this paper provides China's micro-firm-level evidence for the Porter hypothesis.

The impact of technological progress on China's haze pollution-based on decomposition and rebound research.

In order to effectively analyze and explore the socio-economic impact of haze pollution, the article constructs a comprehensive two-stage decomposition model to verify that technological progress plays a key role in controlling haze pollution. And for the first time, a macro-level research framework for the rebound effect of haze pollution has been constructed to compare and analyze the heterogeneity of the rebound effect of technological progress in different industries in different regions. The study found that (1) during the period 2000-2017, haze pollution situation deteriorated. Economic effects were the main reasons for haze pollution. Among these effects, technological progress was the main driving force for haze control, followed by the emission intensity during 2000-2011 and the reduction of industrial structure since 2014. (2) The significant drive of emission reduction is in the secondary industry, showing a trend of first increasing and then decreasing. Besides, there was a difference in spatial distribution, which shows an increased trend from east to west. (3) The rebound effect of haze pollution at the macro level in China presented high-level fluctuations, and there were certain spatial distribution differences. However, due to the convergence of technological development stages, regional differences have a gradual convergence trend. In the future, in the process of haze control, it is necessary to increase support for technological innovation, implement energy total control and price reform, promote technological progress, and implement differentiated haze reduction policies to solve problems according to local conditions.

High-Accuracy Guide Star Catalogue Generation with a Machine Learning Classification Algorithm.

In order to detect gravitational waves and characterise their sources, three laser links were constructed with three identical satellites, such that interferometric measurements for scientific experiments can be carried out. The attitude of the spacecraft in the initial phase of laser link docking is provided by a star sensor (SSR) onboard the satellite. If the attitude measurement capacity of the SSR is improved, the efficiency of establishing laser linking can be elevated. An important technology for satellite attitude determination using SSRs is star identification. At present, a guide star catalogue (GSC) is the only basis for realising this. Hence, a method for improving the GSC, in terms of storage, completeness, and uniformity, is studied in this paper. First, the relationship between star numbers in the field of view (FOV) of a staring SSR, together with the noise equivalent angle (NEA) of the SSR-which determines the accuracy of the SSR-is discussed. Then, according to the relationship between the number of stars (NOS) in the FOV, the brightness of the stars, and the size of the FOV, two constraints are used to select stars in the SAO GSC. Finally, the performance of the GSCs generated by Decision Trees (DC), K-Nearest Neighbours (KNN), Support Vector Machine (SVM), the Magnitude Filter Method (MFM), Gradient Boosting (GB), a Neural Network (NN), Random Forest (RF), and Stochastic Gradient Descent (SGD) is assessed. The results show that the GSC generated by the KNN method is better than those of other methods, in terms of storage, uniformity, and completeness. The KNN-generated GSC is suitable for high-accuracy spacecraft applications, such as gravitational detection satellites.

Socioeconomic factors of industrial air pollutants in Zhejiang Province, China: Decoupling and Decomposition analysis.

In order to analyze and control air pollutant emissions effectively, on the basis of comprehensive consideration of three different pollution sources of industrial sulfur dioxide, industrial nitrogen oxides, and industrial smoke and dust, the Tapio decoupling model and LMDI decomposition model with six decomposition variables are constructed to compare the effects of socioeconomic factors on industrial air pollutant emissions in 11 cities in Zhejiang Province during 2006-2017. Then, a decoupling effort model is developed to analyze the effectiveness of the decoupling efforts taken at city level. This study found that (1) during the period of 2006-2017, the air pollutant emission reduction work in Zhejiang Province achieved remarkable results. More specifically, economic scale effect and population effect are the main factors for the increase of air pollutant emissions. And, the energy emission intensity effect and technological progress are the main driving forces for the reduction of three atmospheric pollutants, followed by the reduction effect of industrial structure and energy structure. (2) The environmental pollution problems of different air pollution sources in different cities are heterogeneous. (3) Eleven cities in Zhejiang Province have made significant decoupling efforts on the emission of three kinds of air pollutants, but there are some differences in the trend of the decoupling effort index of different pollution sources in different cities. In the future, illustrating by the example of Zhejiang, we should implement a "common but different" emission reduction strategy and emphasize pollutant emissions control during energy use in the efforts of further promoting the reduction of air pollutants.

How Would Economic Development Influence Carbon Productivity? A Case from Hubei in China.

Carbon productivity, defined as the gross domestic product (GDP) per unit of CO2 emissions, has been used by provincial governments in China as in indicator for effort and effect in addressing climate-change problems. The aggregate impact of economic growth on carbon productivity is complex and worthy of extensive investigation to design effective environmental and economic policies. Based on a novel combination of the smooth transition regression model and the Markov regime-switching regression model, this paper analyzes time series data on carbon productivity and economic growth from Hubei Province in China. The results show that the influence of economic growth on carbon productivity is highly nonlinear. In general, economic growth has a positive impact on improving carbon productivity. From a longitudinal perspective, this nonlinear positive impact is further divided into three stages, transiting from a high regime to a low regime and then back to a high regime. The high regime stage, in which economic growth has stronger positive influence on enhancing carbon productivity, is expected to last for considerably longer time than the low regime stage. It is more probable for a low regime stage to transit to a high regime. Once the relation of carbon productivity and economic growth enters the high regime status it becomes relatively stable there. If the government aims to achieve higher carbon productivity, it is helpful to encourage stronger economic development. However, simply enhancing carbon productivity is not enough for curbing carbon emissions, especially for fast growing economies.

GMZ-1 is a podophyllotoxin derivative that suppresses growth and induces apoptosis in adriamycin-resistant K562/A02 cells through modulation of MDR1 expression.

The incidence of multidrug resistance (MDR) during cancer chemotherapy is a major challenge for treatment. With the aim of identifying drugs that are capable of targeting treatment­resistant cancer cells, the present study evaluated the efficacy of GMZ­1 in cancer chemotherapy using K562/A02, an MDR leukemia cell line. Cell viability and apoptosis were measured by MTT assay and flow cytometry/Giemsa staining, respectively. The expression levels of the MDR protein 1 (MDR1) gene transcript and protein in K562/A02 cells were determined by reverse transcription­quantitative polymerase chain reaction and western blot analyses, respectively. GMZ­1 suppressed the viability of various human cancer cell lines and induced apoptosis in the K562/A02 cell line in a time­ and concentration­dependent manner. GMZ­1 toxicity may be associated with a decrease in MDR gene expression. These findings demonstrated that GMZ­1 may have efficacy as a potential antitumor drug to overcome leukemia cell resistance to apoptosis induced by chemotherapy.

Underlying mechanism of protection from hypoxic injury seen with n-butanol extract of Potentilla anserine L. in hippocampal neurons.

The alcohol and n-butanol extract of Potentilla anserine L. significantly protects myocardium from acute ischemic injury. However, its effects on rat hippocampal neurons and the mechanism of protection remain unclear. In this study, primary cultured hippocampal neurons from neonatal rats were incubated in 95% N2 and 5% CO2 for 4 hours. Results indicated that hypoxic injury decreased the viability of neurons, increased the expression levels of caspase-9 and caspase-3 mRNA, as well as cytochrome c, Caspase-9, and Caspase-3 protein. Pretreatment with 0.25, 0.062 5, 0.015 6 mg/mL n-butanol extract of Potentilla anserine L. led to a significant increase in cell viability. Expression levels of caspase-9 and caspase-3 mRNA, as well as cytochrome c, Caspase-9, and Caspase-3 protein, were attenuated. The neuroprotective effect of n-butanol extract of Potentilla anserine L. was equivalent to tanshinone IIA. Our data suggest that the n-butanol extract of Potentilla anserine L. could protect primary hippocampal neurons from hypoxic injury by deactivating mitochondrial cell death.

[Proteomic changes in cerebral cortex of neonatal rats with experimental congenital hypothyroidism].

OBJECTIVE: To screen differentially expressed brain proteins with proteomic method in cerebral cortex of neonatal rats with congenital hypothyroidism. METHOD: From the 13th day of gestation, pregnant Wistar rats from the experimental group were given intragastrically with 2.5 ml of 1% propylthiouracil daily. Cerebral cortex specimens were collected from the control and hypothyroidism neonatal rats. Two-directional electrophoresis (2-DE) was applied to analyze protein expression diversities between the euthyroid and hypothyroidism neonatal rat cerebral cortex. Protein spots with significantly different expression were screened and identified by mass spectrometry. Radioimmunoassay (RIA) was used to analyze serum FT(3), FT(4) levels of each groups. RESULT: The body weight of hypothyroid neonatal rats were lower than those in the corresponding control group (t = -8.07, P < 0.01). The FT(3) levels of hypothyroid neonatal rats were lower than those in the corresponding control group (t = 5.39, P < 0.01). The FT(4) levels of hypothyroid neonatal rats were lower than those in the corresponding control group (t = 7.62, P < 0.01). Stable 2-DE maps of normal and CH neonatal rat were constantly obtained. The maps were analyzed by software. Seven protein spots with high reproducibility, high resolution and significantly different expression were chosen and identified by mass spectrometry, including collapsing response mediator protein 2, actin related protein 2/3 complex subunit 5, ubiquitin-conjugating enzyme E2-25K, ATP synthase subunit d, Cu-Zn superoxide dismutase, synuclein alpha, and nucleoside diphosphate kinase. CONCLUSION: The value of this research is demonstrated here by the identification of several proteins known to be associated with nerve synapse structures formation, cell survival, metabolism, cell signal transduction, neural differentiation and nerve growth in the central nervous system. Furthermore this study identified several proteins except for collapsing response mediator protein 2 and Cu-Zn superoxide dismutase that have not previously been described in the literature and which may play an important role as either sensitive biomarkers of brain dysfunction caused by congenital hypothyroidism. In congenital hypothyroidism, brain development retardation may be related with some important processes, including abnormal synaptic formation, excess ROS production and apoptosis. The above-mentioned proteins may play critical roles in the processes, which provide valuable clues to clarify the pathogenesis of brain developmental disorders induced by congenital hypothyroidism.

[Expression of proteins in serum and hippocampus after closed brain injury in rats].

OBJECTIVE: To explore the difference of expression of proteins between the serum and hippocampus after brain injury in rats. METHODS: Male SD rats were used to establish brain injury model. The changes of proteins expression profile in serum and hippocampus at different time after brain injury were analyzed using weak cationic exchanger (WCX2) chips and immobilized metal affinity capture arrays-Cu (IMAC-Cu) chips by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry. RESULTS: A total of 436 protein peaks were detected in serum and 346 protein peaks were detected in hippocampus using WCX2 chips. A total of 229 protein peaks were detected in serum and 345 protein peaks were detected in hippocampus using IMAC-Cu chips. The same 10 protein peaks were respectively detected in serum and hippocampus using WCX2 chips. The same 13 protein peaks were respectively detected in serum and hippocampus using IMAC-Cu chips. CONCLUSION: The changes of protein expression profile in serum and hippocampus are obvious after closed brain injury and show a significant difference. The different proteins detected in serum and hippocampus using the same chip could be biochemical markers for determining brain injury.

[The study in primary cultured astrocytes following fluid percussion injury].

OBJECTIVE: To investigate the morphology alterations and proteomics changes in primary astrocytes following fluid percussion injury. METHODS: Primary cultures of astrocytes were prepared from cerebral hemispheres of 1-3 d-old SD rats, then, astrocytes were randomly divided into control group and injury group which were subjected to (0.2 +/- 0.01) MPa fluid percussion injury. The changes of protein expression pattern in astrocytes between injury and control groups were monitored with two dimensional gel electrophoresis. RESULTS: Astrocytes' s abnonmalities of morphology after injury were apparent. The fluid percussion injury caused astrocytes edema, shrinkage, cell junction disconnection and necrosis at 2 h after injury. 24 h and 48 h after injury, most part of astrocytes's dendrites and soma became hypertrophy and showed a higher rate of cell proliferation. The dynamic proteomics changes were identified and total different 13 spots were detected in this study from the 2DE gels. The different displayed 5 spots were identified via MALDI-TOF: cofilin 1, destrin, phosphoglycerate mutase 1, NADH dehydrogenase (ubiquinone) 1 alpha subcomplex 10, annexin 1. CONCLUSION: The obvious alteration of morphology and protein expression pattern in primary cultured astrocytes could be induced after fluid percussion injury. The differential proteins detected were probably related to stress responses.

[Detection of differential proteins in white matter in brain injury in rat by using a WCX-2 protein chip].

OBJECTIVE: To study the alteration in cortex protein fingerprinting of cerebral cortex after closed brain injury in rat. METHODS: Seventy-two male Sprague-Dawley (SD) rats were randomly divided into sham operation group, 4, 8, 12, 24 and 48 hours postinjury groups. Eight rats in each group were used for WCX-2 protein chip research, and 4 rats in each group for pathological examination. Marmarou's weight-dropping model was reproduced, and brain cortex was harvested for study with hematoxylin-eosin (HE) staining, and Bradford method was adopted for WCX-2 protein chip research, and protein chip reading was obtained for protein fingerprinting analysis. RESULTS: (1) The pathological observation showed different degree of injury could be seen in all the injury groups. (2) The WCX-2 experiment found that 3 protein expressions had changed in cortex after brain injury compared with the sham operation group. The differential protein with molecular weight of 5,639 protein expression was found to be upregulated at 8 hours after injury (P<0.05). The 3,212 protein did not expressed in sham operation or 4, 8, 12 and 24 hours groups, but upregulated at 48 hours after injury (P<0.05). The expression of 7,536 protein was upregulated at 24 hours after injury (P<0.05), but not in sham operation or 4, 8, 12, and 48 hours groups. CONCLUSION: Alterations in protein expression in cerebral cortex could be induced after brain injury.