Non-controlling large shareholders in emerging markets: Evidence from China

Non-controlling large shareholders play an important role in corporate governance in emerging markets where controlling shareholder expropriation is a major concern. We argue that non-controlling large shareholders are faced with two non-conflicting incentives: to take advantage of their information advantage and obtain positive abnormal returns when they trade company shares, and to serve as effective monitors and minimize controlling shareholders\u27 appropriation of company wealth. Using a sample of large shareholders\u27 selling events upon the expiration of the lockup period following the split-share structure reform in China, we find that non-controlling large shareholders successfully time the market, as shown by their positive abnormal returns when selling their shares. Their returns are higher if they have a greater information advantage. Furthermore, the positive returns of the controlling large shareholder are negatively related to non-controlling large shareholders\u27 ownership, suggesting that non-controlling large shareholders play a monitoring role and prevent controlling shareholders from looting the company. We also show that large shareholders affiliated with the controlling shareholders are not subject to as high a level of monitoring as those controlling shareholders are. Furthermore, both firm opaqueness and the severity of agency cost affect the quality of non-controlling large shareholders\u27 monitoring

DYNAMIC ANALYSIS OF 6-TPS PARALLEL MECHANISM

Establish the moving-platform velocity and acceleration relationship between all members and joints of 6-TPS parallel mechanism. The mechanism output speed is used as the independent variable,and set up the mechanism motion differential equations by Kane method. The equation can be used as a dynamic control model and be completely closed loop control of the mechanism. Using matrix norm,derive the perturbation relation of relative variation between the active joint driving force and inertia matrix and the acceleration,put forward the quantitative index of the mechanism acceleration performance and dynamic optimization. Conclude that mechanism acceleration performance indicators is in the singular path limit of the inertia matrix in the working space by an example,and can be used to select the working space of excellent dynamic performance

Spatial and Temporal Dynamics of Wetlands in Guangdong-Hong Kong-Macao Greater Bay Area from 1976 to 2019

Wetland ecosystems contain rich natural resources and vital ecological functions, and the investigation of spatial and temporal evolution characteristics of wetlands and their driving factors is critical for the management and conservation of wetlands. This study aimed to explore the spatial and temporal dynamics of wetlands in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) from 1976 to 2019 using multi-source remote sensing data (DISP KH-9, Landsat, and GaoFen-1), combing with the object-based classification method and landscape invasion index, and further analyze the driving forces affecting the spatial and temporal evolution of wetlands. The results showed that: (1) The total area of wetlands in the GBA showed a trend to first increase and then stabilize from 1976 to 2019. (2) The rapid development of aquaculture led to a continuous increase in aquaculture ponds and offshore aquaculture and a flat change in the middle and late stages, the area of mangroves declined substantially before 2000 and has gradually recovered since then, the invasion of various types of wetlands by built-up land is increasing, and wetlands are becoming increasingly fragmented. (3) The wetland changes in the GBA are the result of a combination of natural factors and human activities. Environmental conditions represent the basis for wetland dynamics, while the population, socio-economics, and policies are important drivers of wetland evolution. The findings will be beneficial to the understanding of wetland dynamic changes in the GBA over the past 40 years, and helpful to the scientific management and sustainable development of wetlands

Spatial and Temporal Dynamics of Wetlands in Guangdong-Hong Kong-Macao Greater Bay Area from 1976 to 2019

Wetland ecosystems contain rich natural resources and vital ecological functions, and the investigation of spatial and temporal evolution characteristics of wetlands and their driving factors is critical for the management and conservation of wetlands. This study aimed to explore the spatial and temporal dynamics of wetlands in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) from 1976 to 2019 using multi-source remote sensing data (DISP KH-9, Landsat, and GaoFen-1), combing with the object-based classification method and landscape invasion index, and further analyze the driving forces affecting the spatial and temporal evolution of wetlands. The results showed that: (1) The total area of wetlands in the GBA showed a trend to first increase and then stabilize from 1976 to 2019. (2) The rapid development of aquaculture led to a continuous increase in aquaculture ponds and offshore aquaculture and a flat change in the middle and late stages, the area of mangroves declined substantially before 2000 and has gradually recovered since then, the invasion of various types of wetlands by built-up land is increasing, and wetlands are becoming increasingly fragmented. (3) The wetland changes in the GBA are the result of a combination of natural factors and human activities. Environmental conditions represent the basis for wetland dynamics, while the population, socio-economics, and policies are important drivers of wetland evolution. The findings will be beneficial to the understanding of wetland dynamic changes in the GBA over the past 40 years, and helpful to the scientific management and sustainable development of wetlands

Proliferation and Anti-inflammatory Effects of Tremella fuciformis Polysaccharide on Human Chondrocytes

Objective: Osteoarthritis (OA) is a prevalent chronic joint disease. The purpose of this study was to investigate the proliferative and anti-inflammatory effects of Tremella fuciformis polysaccharide on osteoarthritis cell model human chondrocyte T/C-28a2. Methods: Proliferative effect and cytotoxicity of T/C-28a2 cells treated by Tremella fuciformis polysaccharide were detected with MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide) and crystal violet staining experiment. The bone inflammation model was established by lipopolysaccharide (LPS) treatment in T/C-28a2 cells. The expression of interleukin-6 (IL-6) in cells after drug treatment was detected by enzyme-linked immunosorbent assay (ELISA) analysis. The expression of osteoprotegerin (OPG) and inflammatory factors after drug treatment was detected by Western blot analysis. In addition, reactive oxygen species (ROS) release assay was used to detect the level of oxidative stress and anti-inflammation response to cells. Results: Tremella fuciformis polysaccharide could promote proliferation of human chondrocyte T/C-28a2 without obvious cytotoxicity. After LPS was used to treat human chondrocytes to simulate the environment of bone inflammation, it was found that the treatment of Tremella fuciformis polysaccharide and chondroitin sulfate could reduce the secretion of IL-6 and inhibit the occurrence of inflammation. Further Western blot analysis showed that after treatment of Tremella fuciformis polysaccharide, expression of related osteoprotegerin (OPG) was upregulated, expression of proapoptosis-related protein Bax, extracellular signal-regulated kinase ERK-MAPK and nuclear factor κB (NF-κB) was down-regulated. ROS release experiment showed that Tremella fuciformis polysaccharide and chondroitin sulfate could inhibit intracellular ROS levels and the occurrence of inflammatory response. Conclusion: Tremella fuciformis polysaccharide exhibited the effect of inhibiting osteoarthritis, protecting cartilage tissue and resisting cell apoptosis to a certain extent. In this study, the anti-inflammatory effect of Tremella fuciformis polysaccharide and its mechanism were primarily explored, which provided the preliminary experimental basis for the development of Tremella fuciformis polysaccharide as an anti-inflammatory drug

Study of SARS-CoV-2 transmission in urban environment by questionnaire and modeling for sustainable risk control

Caused by SARS-CoV-2, COVID-19 has become a severe threaten to society and human health, its epidemic control emerges as long-term issue. A sustainable epidemic and environmental transmission risk control (SEERC) in urban area is urgently needed. This work aims to conduct a new investigation on the transmission risk of SARS-COV-2 as virus/hazardous material through various environmental medias, routes and regions in the entirely urban area for guiding the SEERC. Specifically, 5 routes in 28 regions (totally 140 scenarios) are considered. For a new perspective, the risk evaluation is conducted by the quantification of frontline medicals staffs’ valuable experience in this work. 207 specialists responsible for the treatment of over 9000 infected patients are involved. The result showed that degree of risk was in the order of breath>contact-to-object>contact-to-human>intake>unknown. The modeling suggested source control as the prior measure for epidemic control. The combination of source control & mask wearing showed high efficiency in SEERC. The homeworking policy needed to cooperate with activity limitation to perform its efficiency. Subsequently, a new plan for SEERC was discussed. This work delivered significant information to researchers and decision makers for the further development of sustainable control for SARS-COV-2 spreading and COVID-19 epidemic

Epigenetic silencing of miR-493 increases the resistance to cisplatin in lung cancer by targeting tongue cancer resistance-related protein 1(TCRP1)

Abstract Background The potential mechanisms regarding how methylation of microRNA(miRNA) CpG Island could regulate cancer cell chemo-resistance remains unclear. This study aims to explore the epigenetic dysregulation mechanism of miRNA-493 and the ability to modulate lung cancer cell chemotherapy resistance. Methods Real-time quantitative PCR (qRT-PCR) and In situ hybridization (ISH) were used to analyze the expression of miR-493 in lung cancer cell lines and tumor tissue, respectively. Bisulfite sequencing PCR (BSP) was used to exam the promoter CpG Island of miR-493. The effect of miR-493 on chemosensitivity was evaluated by cell viability assays, apoptosis assays and in vivo experiment. The DNA damage was measured by γ-H2AX immunofluorescence. Luciferase reporter assay was used to assess the target genes of miR-493. Expression of target proteins and downstream molecules were analyzed by Western blot. Results miR-493 is silenced in resistant lung cancer cell due to the aberrant DNA methylation. Enforced expression of miR-493 in lung cancer cells promotes chemotherapy sensitivity to cisplatin through impairing the DNA damage repair and increasing the cells apoptosis in vitro and in vivo. Furthermore, we identify that TCRP1 is a direct functional target of miR-493. Ectopic expression of TCRP1 attenuated increased apoptosis in miR-493-overexpressing lung cancer cells upon cisplatin treatment. Meanwhile, miR-493 level is negatively correlated with TCRP1 expression in lung cancer patients and TCRP1 expression were correlated with poor survival. Conclusions Our results highlight that hyper-methylation of miR-493CpG island might play important roles in the development of lung cancer chemo-resistance by targeting TCRP1, which might be used as a potential therapeutic target in preventing the chemo-resistance of lung cancer

Design and Microwave-Assisted Synthesis of Novel Macrocyclic Peptides Active at Melanocortin Receptors: Discovery of Potent and Selective hMC5R Receptor Antagonists

Differentiation of the physiological role of the melanocortin receptor 5 MC5R from that of other melanocortin receptors will require development of high affinity and selective antagonists. To date, a few synthetic antagonist ligands active at hMC5 receptor are available, but most do not have appreciable selectivity. With the aim to gain more potent and selective antagonists for the MC5R ligands, we have designed, synthesized, and pharmacologically characterized a series of alkylthioaryl-bridged macrocyclic peptide analogues derived from MT-II and SHU9119. These 20-membered macrocycles were synthesized by a tandem combination using solid phase peptide synthesis and microwave-assisted reactions. Biological assays for binding affinities and adenylate cyclase activities for the hMC1R, hMC3R, hMC4R, and hMC5R showed that three analogues, compounds, 9, 4, and 7, are selective antagonists at the hMC5 receptor. In particular, compound 9(PG-20N) is a selective and competitive hMC5R antagonist, with IC50 of 130 ± 11 nM, and a pA2 value of 8.3, and represents an important tool for further biological investigations of the hMC5R. Compounds 4 and 7 (PG14N, PG17N) show potent and selective allosteric inhibition at hMC5R with IC50 values of 38 ± 3 nM and 58 ± 6 nM, respectively. Compound 9 will be used to further investigate and more clearly understand the physiological roles played by the MC5 receptor in humans and other animals

Modeling the Pathogenesis of Charcot-Marie-Tooth Disease Type 1A Using Patient-Specific iPSCs

Summary: Charcot-Marie-Tooth disease type 1A (CMT1A), one of the most frequent inherited peripheral neuropathies, is associated with PMP22 gene duplication. Previous studies of CMT1A mainly relied on rodent models, and it is not yet clear how PMP22 overexpression leads to the phenotype in patients. Here, we generated the human induced pluripotent stem cell (hiPSC) lines from two CMT1A patients as an in vitro cell model. We found that, unlike the normal control cells, CMT1A hiPSCs rarely generated Schwann cells through neural crest stem cells (NCSCs). Instead, CMT1A NCSCs produced numerous endoneurial fibroblast-like cells in the Schwann cell differentiation system, and similar results were obtained in a PMP22-overexpressing iPSC model. Therefore, despite the demyelination-remyelination and/or dysmyelination theory for CMT1A pathogenesis, developmental disabilities of Schwann cells may be considered as an underlying cause of CMT1A. Our results may have important implications for the uncovering of the underlying mechanism and the development of a promising therapeutic strategy for CMT1A neuropathy