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We consider a Cournot duopoly consisting of two geographically separated firms, each associated with a local environmental-friendly trade union that exhibits climate solidarity. In the basic model, firms choose abatement technologies prior to bargaining over wages and employment with the unions. We show that wage demanded is decreasing as the union's degree of climate solidarity increases, providing additional incentives for firms to adopt greener technology, hence improving the social welfare. In the alternative model, where trade unions decide the wages prior to the firms' abatement and employment decisions, the firms choose the dirtiest available technology implying that the union's climate solidarity has no effect on the firm's abatement decisions. These results suggest that establishing climate solidarity as a norm across trade unions can, depending on the timing of the environmental technological choice, become a powerful instrument in battling climate change, critically supplementing the as yet ineffective international policy framework.

This paper first examines some recent exchange rate classification schemes. There is little evidence of a trend towards greater agreement between schemes. There is a probability of between 16 and 28% that a peg in one classification scheme is coded as a float in a different scheme, or vice versa. This probability is much smaller for the tightest forms of peg and the most volatile floats. Continuous indices of exchange rate flexibility are analysed and shown to have significant potential, despite the lack of interest in them shown in previous research.

This study aims to evaluate the efficacy of acupuncture on the sleep structure of patients with insomnia, so as to provide a valuable basis for the effectiveness of acupuncture in the treatment of insomnia. We conducted searches based on MeSH terms and free words in Cochrane Library, PubMed, Web of science, CKNI (China Knowledge Resource Integrated Database), WanFang Database, and Chongqing VIP Information from the inception of these database until 10 July 2020 for randomized controlled trials (RCTs) that investigated acupuncture treatment in patients with insomnia, and pertinent details of the results were saved. Comprehensive analysis showed that: (1) compared with the Western medicine groups, the acupuncture groups showed significant advantages in reducing the percentage of N1 sleep stage and N2 sleep stage, as well as increasing that of N3 sleep stage and REM sleep stage. However, no significant difference was found in increasing the effective rate, reducing total PSQI score, improving the total sleep time, reducing sleep latency, and improving sleep efficiency between the Western medicine groups and the acupuncture groups. (2) Compared with the sham acupuncture groups, the acupuncture treatment showed advantages in increasing the effective rate, reducing Pittsburgh Sleep Quality Index (PSQI) score, increasing the total sleep time, and improving sleep efficiency. However, no significant difference was observed between the sham acupuncture groups and the acupuncture groups with regard to reducing sleep latency, the percentage of N1 sleep stage and N2 sleep stage, as well as increasing that of N3 sleep stage and REM sleep stage.本研究旨在评价针刺对失眠症患者睡眠结构的影响，为针刺治疗失眠症的疗效提供有价值的依据。方法:基于主题词和自由词，我们通过计算机检索了Cochrane Library， PubMed, Web of science，中国知网，万方数据库，重庆维普数据库，对针刺治疗失眠症患者的相关随机对照试验(RCTs)进行检索，设置检索时间为建库至2020年7月10日，并保存了相关细节。结论:综合分析表明:1.与西药组相比，针刺组在减少N1睡眠阶段和N2睡眠阶段的百分比，以及增加N3睡眠阶段和REM睡眠阶段的百分比方面有显著优势，但在提高治疗有效率、降低PSQI总分、增加睡眠总时间、缩短睡眠潜伏时间以及提高睡眠效率等方面两组之间没有显著差异；2.与假针刺组相比，针刺组在提高治疗有效率、降低PSQI总分、增加睡眠总时间及提高睡眠效率方面有优势，然而，在缩短睡眠潜伏时间、减少N1睡眠阶段和N2睡眠阶段的百分比，以及增加N3睡眠阶段和REM睡眠阶段的百分比方面，两组之间没有显著性差异。.

Structural proteins play critical roles in the food quality, especially texture properties, of sea cucumbers and their products. Most of the previous studies on sea cucumbers focused on few individual proteins, which limited our understanding of how structural proteins influenced the quality of sea cucumbers. Inspired by the clarification of sea cucumber (Apostichopus japonicus) genome, we established an integrated data of structural proteins in the sea cucumber body wall. A portfolio of 2018 structural proteins was screened out from the sea cucumber annotated proteome by bioinformatics analysis. The portfolio was divided into three divisions, including extracellular matrix proteins, muscle proteins, and proteases, and further classified into 18 categories. The presence of 472 proteins in the sea cucumber body wall was confirmed by using a proteomics approach. Moreover, comparative proteomics analysis revealed the spatial distribution heterogeneity of structural proteins in the sea cucumber body wall at a molecular scale. This study suggested that future researches on sea cucumbers could be performed from an integrated perspective, which would reshape the component map of sea cucumber and provide novel insights into the understanding of how the food quality of sea cucumber was determined on a molecular level.

The objective of this study was to investigate the complex coacervation between ovalbumin (OVA) and carboxymethylcellulose (CMC) with different degrees of substitution (CMC 0.7 and CMC 1.2). Turbidity titration showed that complexes or coacervates could form between OVA and CMC by electrostatic interactions depending on pH changes. Specially, the critical pH values (pHc, pHφ1) increased with the salt ion concentration raising from 0 to 20 mM, while further increasing the ionic strength reduced the formation of complex coacervates. The ITC results also showed that when CNaCl = 20 mM, the complex coacervation between OVA and CMC exhibited the highest stoichiometric ratio and binding constant. When CNaCl≥200 mM, the complex coacervation changed from spontaneous exothermic (ΔG 0) due to the shielding effect by high concentration of salt ions. In addition, dynamic rheological properties showed that the OVA/CMC coacervates displayed the strongest elastic modulus at CNaCl = 20 mM, and the elastic modulus of all samples were greater than the viscous modulus. These findings all suggested a salt-enhanced effect at lower salt concentrations or a salt-reduced effect at higher salt concentrations. On the other hand, the stoichiometric and viscoelastic properties of OVA/CMC 1.2 coacervates were greater than OVA/CMC 0.7 coacervates, indicating that CMC 1.2 had stronger protein binding capacity owing to higher charge density.

Ginsenoside-Rg1, the main active component of Panax notoginseng, exhibits a number of pharmacological functions, including promoting protein synthesis in the brain, increasing the number of synapses, improving memory and promoting recovery of brain function following injury. The effect of ginsenoside-Rg1 on proliferation and glial-like-directed differentiation in the cortical neural stem cells (NSCs) of embryonic rat brain was investigated. The present study used MTS assays to identify the optimum dose and window time of ginsenoside-Rg1 administration to stimulate the proliferation of cortical NSCs in the rat embryonic tissue. The oxygen glucose deprivation (OGD) set-up was used as a cell injury model. Immunofluorescent staining was used for identification of NSCs and subsequent observation of their proliferation and glial-like directed differentiation. Nestin expression was the marker for the presence of NSCs among the cortical cells of embryonic rat brain. The optimum dose of ginsenoside-Rg1 for proliferation of NSCs was 0.32 µg/ml. The optimum window time of 0.32 µg/ml ginsenoside-Rg1 administration on proliferation of NSCs was 6 h. Ginsenoside-Rg1 at 0.32 µg/ml concentration promoted incorporation of bromo-2-deoxyuridine, and expression of nestin and vimentin in primary and passaged NSCs, and NSCs following OGD. Ginsenoside-Rg1 had a role in promoting proliferation and glial-like-directed differentiation of cortical NSCs. The plausible explanation for these responses is that ginsenoside-Rg1 acts similarly to the growth factors to promote the proliferation and differentiation of NSCs.

Thebaojiasystem was a Chinese mechanism of social control in rural areas. The Japanese authorities revived this system in the villages of Manchuria in the mid-1930s. Thebaojiasystem placed the villages under the control of the state by registering population, organising village defence corps and instituting internal surveillance. Thebaojiasystem also functioned as a source of revenue for the state. This article examines the structural characteristics of thebaojiasystem and the way it was implemented in practice. It argues that thebaojiasystem as a tool for social control served the temporary purpose of maintaining security in Japanese-administered rural Manchukuo.

We investigated the effects of cortical devascularization on the proliferation, differentiation, and migration of neural stem cells (NSCs) in the subventricular zone (SVZ) of the lateral ventricle of adult rats. 60 adult male Wistar rats were randomly divided into control group and devascularized group. At 15 and 30 days after cerebral cortices were devascularized, rats were euthanized and immunohistochemical analysis was performed. The number of PCNA-, Vimentin-, and GFAP-positive cells in the bilateral SVZ of the lateral wall and the superior wall of the lateral ventricles of 15- and 30-day devascularized groups increased significantly compared with the control group (P<0.05andP<0.01). The area density of PCNA-, Vimentin-, and GFAP-positive cells in cortical lesions of 15- and 30-day devascularized groups increased significantly compared with the control group (P<0.05andP<0.01). PCNA-, GFAP-, and Vimentin-positive cells in the SVZ migrated through the rostral migratory stream (RMS), and PCNA-, GFAP-, and Vimentin-positive cells from both the ipsilateral and contralateral dorsolateral SVZ (dl-SVZ) migrated into the corpus callosum (CC) and accumulated, forming a migratory pathway within the CC to the lesioned site. Our study suggested that cortical devascularization induced proliferation, glia-directed differentiation, and migration of NSCs from the SVZ through the RMS or directly to the corpus callosum and finally migrating radially to cortical lesions. This may play a significant role in neural repair.

Sea cucumbers attracted increasing interest due to its nutritional functions. Collagen is the most important structural biomacromolecule in sea cucumber body wall, and is highly related to the textual properties and food quality of sea cucumber. In this study, the type of constituent collagens of sea cucumber collagen fibrils was investigated, employing a commercially important species Apostichopus japonicus as the material. Proteomics and bioinformatics analysis revealed that collagen fibrils of A. japonicas are heterotypic. Two clade A and one clade B fibrillar collagens and two FACIT collagens were identified from the fibrils. Besides, the heterogeneity was also revealed in the pepsin-solubilized collagen (PSC) of A. japonicus by using the proteomics strategy. It implied that the previous conclusions on the type of sea cucumber collagen deduced from SDS-PAGE analysis should be rechecked. The results provided novel insight into the composition of sea cucumber collagen fibrils.

The present study comprised a series of experiments to investigate the mechanism underlying the effect of ginsenoside on the self-renewal, proliferation and differentiation of neural stem cells (NSCs) undergoing oxygen-glucose deprivation/reperfusion (OGD/R) in vitro. The NSCs, which were isolated from the hippocampus of embryonic day 17 embryo rats, were subjected to OGD/R to establish an in vitro model of brain ischemia-reperfusion, following which different doses of ginsenoside were administered to the model. The proliferation of the NSCs was determined using MTT colorimetry and nestin/bromodeoxyuridine (BrdU) immunofluorescent double-labeling. The NSCs were identified by measuring the expression of nestin, and the differentiation of NSCs was assessed through the immunofluorescent double-labeling of nestin/vimentin and nestin/neuron-specific class III β-tubulin (tuj-1). The protein levels of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α (HIF-1α) were detected to investigate the function and mechanism of ginsenoside on ischemic stroke using an enzyme-linked immunosorbent assay. Marked increases in the optical density, area density and numbers of nestin/BrdU-, nestin/vimentin- and nestin/tuj-1-positive cells were found in the ginsenoside-treated group. Compared with the control group, enhanced expression levels of BrdU, tuj-1 and vimentin were found in the ginsenoside-treated group, suggesting that ginsenoside may significantly promote the proliferation and differentiation of NSCs. The results of the present study also showed that ginsenoside significantly increased the protein level of HIF-1α (P

The contribution of the emulsion rheological properties and the viscoelastic of the interface adsorbed layer to the emulsification mechanism of ovalbumin (OVA)-chitosan (CS) mixtures were investigated. In comparison to the treatment with OVA alone and OVA/CS mixtures at pH 4.0, the addition of CS at pH 5.5 increased the size distribution of emulsion droplets with significant flocculation through polyelectrolyte bridging, remarkably enhancing the emulsions stability against gravity creaming after storage at 25 °C for 14 days. The dynamic rheological properties indicated that the formation of the complex at pH 5.5 increased the elastic modulus (G′) and apparent viscosity (η∗) of the emulsions, which is useful for inhibiting creaming. Moreover, the complexation of OVA and CS at pH 5.5 increased the dilatational modulus (E), especially the elastic modulus (Ed), of the oil/water interfacial absorbed layer, which could reduce the droplet coalescence and therefore inhibit the growth of emulsion droplets.

A new and easily implemented regression method is proposed for generating an index of exchange rate flexibility, whilst simultaneously identifying anchors of pegged currencies. The method can distinguish floats from pegs, including those with occasional devaluations. An annual index is calculated that can be compared with other regime classification schemes, or used directly in empirical research as a measure of exchange rate flexibility. Different categories in the IMF’s de facto classification, and also in the Reinhart-Rogoff classification, are associated with significantly different average values of the index. Further analysis of managed floats shows that they have a strong tendency to track the US dollar.

Theory suggests a significant positive relationship in long-run equilibrium between the net foreign assets (NFA) of a country and its real exchange rate. Empirical tests have ignored two issues: the large variation in cross-country trade/GDP ratios, which is likely to induce substantial cross-country differences in coefficients when net foreign assets are scaled by GDP, and the reverse causality associated with valuation effects. A real exchange rate appreciation reduces the absolute value of NFA denominated in foreign currency relative to domestic GDP, because of the sizeable component of non-tradable goods in domestic GDP. This endogeneity biases the test results. New tests are implemented that address these issues. The valuation effect bias is found to be significant. The new tests nevertheless still support the existence of a long-run positive relationship between NFA and real exchange rates.

The hydroxyapatite (HA)/ TiO2composite ceramic coatings were formed by micro-arc oxidation (MAO) on pure titanium in mixed electrolyte of calcium glycerophosphate and calcium acetate with DC pulse power. Microstructure, phase composition, porosity and thickness of the coatings were examined using SEM, XRD, Image-Pro Plus 6.0 Image analysis system and Eddy current thickness gauge. Results indicate that MAO coatings containing calcium and phosphorus were formed in situ on pure titanium surface. Pores formed by the discharge channels distribute uniformly on the coatings surface, and the inner layer is dense. The principal crystalline phases of the MAO coatings are anatase TiO2, rutile TiO2, HA, Ca3(PO4)2and matrix Ti. The interface is metallurgical bonding and the bonding strength is strong. And reaction time makes a greater influence than voltage in thickness and voltage makes a greater influence than time in porosity.

Irradiation crosslinking is one of the most important methods to modify UHMWPE, it can effectively improve the hardness, creep resistance and abrasion resistance of this material. In order to eliminate free radical, increase material strength, abrasion resistance and fatigue resistance of creep, this study uses Co60-γ to modify UHMWPE under vacuum atmosphere, with the irradiation dose of 30, 60, 90, 120 Kgy respectively. Its mechanical properties, microstructure, degree of crosslinking and crystallinity are analyzed, the results show that the modified UHMWPEs impact strength decreased, elongation basically remain unchanged, tensile fracture strength and tensile yield strength increased.

There exist several statistically-based exchange rate regime classifications that disagree with one another to a disappointing degree. To what extent is this a matter of the quality of the design of these schemes, and to what extent does it reflect the need to supplement statistics with other information (as is done in the IMF’s de facto classification)? It is shown that statistical methods are good at the basics (distinguishing some type of peg from some type of float), but less helpful in other respects, such as determining whether a float is managed, particularly for countries that are not very remote from their main trading partners. Different measures of exchange rate volatility have been used but are not primarily responsible for differences between classifications. The theoretical underpinning of particular classification schemes needs to be more explicit.

The feedback-based technical scheme of Metro regenerative braking energy can effectively solve the rapid transfer and comprehensive utilization of regenerative electric energy and can effectively alleviate the reverse impact of regenerative electric energy on traction power supply system. In order to quantify the feedback power capacity and optimize the train dispatching, a simple engineering calculation method of regenerative braking energy is proposed in this paper. Firstly, the basic resistance calculation model is established and the braking characteristics of the vehicles are analysed by using the actual parameters of Metro vehicles. Secondly, the calculation method of regenerative energy is deduced by the energy conversion and balance equation. Finally, the calculation procedure of regenerative braking energy is explicated by an example, and the accuracy of the calculation results is verified.

The raw data suggest that the global trend towards greater exchange rate flexibility that was evident before 1990 has since stopped. An optimum currency area (OCA) model of exchange rate regime choice is estimated. Four different schemes for classifying exchange rate regime are investigated. Trends in the explanatory variables made little difference to the trend towards greater flexibility before 1990 but have worked against it since, largely because of the reduction in inflation. Underlying preferences are still shifting gradually in the direction of greater flexibility.

Low temperature aging (LTD) is an important factor of Y-TZP ceramic as artificial joint femoral head and dental restorative materials in vivo for long-term application. In this paper, the accelerated aging experiments on Y-TZP ceramics were conducted. The t-m phase transition is occurring from the surface to the inside during low temperature aging of Y-TZP ceramics. As content of phase transformation increases, thickness of phase transformation layer increases. While the content of surface monoclinic phase is less, the volume expansion and surface stress caused by phase transformation can make cracks and holes shrink or even close, then the flexural strength increase. As a large number of surface monoclinic phase was generated, due to there are a lot of microscopic defects in the phase transition layer, crystals loose, strength of grain boundary lower than that of not aging area and phase transformation layers fracture in the intergranular mode, that damages the flexural strength. Therefore, the flexural strength increase firstly and then decrease with the increase of surface monoclinic content.

The purpose of this study was to study effects of the mechanical properties of veneering porcelain on stress distribution of dental zirconia layered structure by three-dimensional finite element analysis. A 3-D geometric model of the first maxillary molar was established, a tooth preparation was simulated by the Imageware software. A crown was designed and divided into three layers: core, middle layer and outer veneer layer. The elasticity modulus of the middle layer was 70GPa for the control model up to 175GPa for the tested models. Loads of 200N were applied over a 1 mm diameter area beneath the tip of the mesial-distal cusp, simulating typical occlusal contact areas, the stress distribution of the crown systems were analyzed. Results show that within the geometry of the crown configuration, one concentration district of maximum principal stress occurred on the occlusal surface closely proximal to the loading position, several sub-maximum principal stress area were observed, such as margin regions of the mesial face, lingual face, distal faces, buccal face and occlusal fossa. Middle layer with higher modulus can effectively disperse the stress concentration in the layered zirconia all-ceramic crown system.

The matching properties of ceramics and veneering porcelain play an important role for the overall color and mechanical properties of dental crowns. The Vita VM9 veneering porcelain was coated on the surfaces of two zirconia, three-point flexural strength, heat shock resistance and the overall color after veneered with porcelain were tested. The results showed that the interlayer cracks, radial cracks or porcelain body cracks were not appeared in all samples during thermal shock experiments at 60~220°C. Their flexural strength was all above 700MPa and the overall color covered the common color of VITA-3D Master shade guide. There is good thermal compatibility between the two dental shaded zirconia ceramics and Vita VM9 veneering porcelain. The mechanical properties are suitable for clinical posterior teeth area restorative, and the overall color is also suitable for the requirements on the color and brightness of clinical dental restoration.

We investigate monthly bilateral exchange rate volatility for a large sample of currency pairs over the period 1999-2006. Pegs (particularly to the US dollar) and managed floats tend to have lower volatility than independent floats. A deeper investigation shows that the peg effect operates almost entirely through currency networks (i.e. where two currencies are pegged to the same anchor currency), and the lower volatility of US dollar pegs reflects the size of the US dollar network. Managed floats show clear evidence of tracking the US dollar, further increasing the effective size of the US dollar network. Inflation undermines the currency-stabilizing effect of peg networks. Currencies in smaller peg networks have higher unweighted but not trade-weighted exchange rate volatility, which is consistent with anchors being chosen to minimize trade-weighted volatility. The size of the effective US dollar network revealed here is a plausible explanation of the rarity of basket pegs. Volatility also reflects a range of structural factors such as country size, level of development, population density, inflation differentials and business cycle asymmetry.

Bilayered three-point bending strength specimen of KAVO zirconia-Vita VM9 veneering porcelain were made according to ISO6872 standard, the core to porcelain thickness ratio was 1:1. Specimens were subjected to multiple dentine porcelain firing cycles. Three-point bending strength were tested, SEM was used to observe the characteristics of the failure mode. Results show that there was no influence on the bending strength by multiple firing, the three-point bending strength were 996 ~ 1020 MPa after multiple firing, and no obvious defects was found at the interfaces. In all bilayered specimen, the bulk fracture initiated at the tensile surface of the core material and was consistently accompanied with porcelain crush and delamination at the interface.

Objective: To investigate the effects of different surface treatments on the microstructural and crystallographic changes of dental 3Y-TZP ceramics. Methods: 21 pieces of zirconia specimens (15 ´ 15 ´ 1.5 mm) were prepared and divided into 7 groups: control group; grinding group; polishing group; sandblasting group; sandblasting + veneer porcelain sintering group; sandblasting + veneer porcelain sintering twice group and sandblasting + annealing group. The crystal structure of specimen was monitored by X-ray diffraction (XRD) before morphological observation with scanning electron microscope. Results: monoclinic phase increased after grinding while decreased little after polishing, bigger phase change presented after sandblasting compared with decreased phase change induced by veneer porcelain sintering; annealing eradicated the surface m phase. Grinding produced coarse scratches on the surface of samples with removal of surface particles; after grinding and polishing to 7 um level, the surface particles were removed massively, and the surface became smooth with remaining scare scratches and substantial micro cracks. Sandblasting removed scratches near completely producing coarse and irregular surface of samples. Conclusions: Grinding, sandblasting and polishing could produce the transition of Zirconia Ceramic surface from t to m phase. It is better to use heat treatment after mechanical treatment to reverse the changed surface phase.

Osteonecrosis of the femoral head is a debilitating and painful orthopedic condition characterized by joint collapse. Salvage of the femoral head is highly desirable to preserve the contour and mechanical properties and prevent joint collapse. This study aimed to develop a new tissue-engineering approach for treatment of large bone defect in femoral head, that is, after osteonecrosis. The biphasic calcium phosphate (BCP) ceramic scaffolds were fabricated by a 3D gel-lamination technique based on micro-computed tomography (micro-CT) images of the cancellous bone microarchitecture of femoral heads. After seeding with autologous bone marrow-derived mesenchymal stem cells (BMSCs) in vitro, the cell-scaffold composite was implanted into a bone defect surgically induced in canine femoral head via trapdoor procedure, which was a common procedure for treatment of osteonecrosis. A total of 24 adult dogs were randomly divided into three groups (n = 8 each) for implantation of the BCP scaffold with or without with BMSCs, and also the autologous bone chips for comparisons. All animals were sacrificed at 30 weeks postoperatively and processed for radiological and histological evaluations. The contour of the femoral head was well preserved with implantation of BCP scaffolds with or without BMSCs, whereas joint collapse was found after treatment with autologous bone chips. The osteointegration and new bone formation was significantly greater with BCP scaffold implantation with than without BMSC seeding and showed greater strength and compressive modulus in the repair site. Micro-CT-based bone ceramic scaffolds seeding with BMSC might be a promising way to repair bone defects in the femoral head.