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The transmission efficiency of belt continuously variable transmission (CVT) generally fluctuates around 80%. In order to further improve transmission efficiency, gain economic benefit and reliability, domestic all-terrain off-road vehicle (ATV) is taken as the study object which presents problems such as low transmission efficiency, rubber belt slipping under heavy load condition and short working life of belt in the running test. The structure of the rubber belt CVT is simplified, and the influences of three key components, driving wheel limit spring, centrifugal fly hammer and slave wheel pressure torsion spring, on the performance of CVT are analyzed by using CVT experimental bench. The results show that the efficiency of rubber V-belt CVT is improved by optimizing the stiffness of the spring and the mass of centrifugal fly hammers, and reasonably matching parameters. This study provides some reference of experimental analysis method and performance data for the design of high efficiency rubber V-belt CVT.

In order to investigate the corrosion resistance of reinforced gabion rebars in dry and wet cyclic salt environments，the failure behavior of HPB300 ordinary steel，NH400 weathering steel，NS142 and NS336 corrosion resistance steels in a dry and wet cyclic salt spray [5%(mass fraction) NaCl solution] corrosion environment was studied by dry and wet cyclic accelerated corrosion test.The changes in corrosion rate，phase，morphological structure and electrochemical properties of 4 types of steels in a dry wet cyclic salt solution medium were studied by corrosion weight loss method，XRD，SEM and electrochemical test，and the changes in corrosion resistance and mechanical properties of 4 types of steel in simulated accelerated environment were further compared and analyzed.Results showed that after 105 cycles of accelerated cycling in 5%NaCl solution corrosion medium，the corrosion rates of HPB300 steel and NH400 steel were significantly higher than that of NS142 and NS336，and the self-corrosion potential was more negative.After accelerated corrosion test，the tensile strength of HPB300 steel could no longer meet the application requirements of reinforced gabion rebars，whereas the tensile strength of NH400，NS142 and NS336 still met the service conditions.Therefore，NS142 and NS336 corrosion resistant steel were more suitable for the application of reinforced gabion rebars in salt spray corrosion environment.

In the context of intelligent power consumption, household users can promote the safe, stable and economic operation of the power system by participating in electricity demand response and obtain additional benefits. Therefore, a strategy for demand response based on family agglomeration is proposed in this paper. Firstly, the concept of family clustering is proposed to manage the aggregation of residents' families into communities and to design the response mechanism on the residents' side. Secondly, considering the residents' electricity consumption habits and influencing factors during demand response, the responding load function of household electricity consumption is constructed, which quantifies the potential of household demand response. On this basis, a response strategy is designed which takes both the degree of completion and user experience into account. Finally, three specific indicators are proposed to evaluate the response strategy, namely task completion rate, user discomfort and economic benefits. An example is given to verify the effectiveness and economy of the proposed strategy.

A preparation process of No-Carrier-Added (NCA) 177Lu in China Mianyang Research Reactor (CMRR）was investigated. In this work, the key component of the process is DGA resin column which can adsorb Yb(Ⅲ) and Lu(Ⅲ) metal ions in the eluent was added to the purification process of 177Lu. The eluent “on-line” cyclic elution of lanthanide resin column was realized through special flow path connection. The tracer test showed that this technology can effectively reduce the volume of radioactive acid waste liquid generated from purification process of 177Lu. The technology was verified in three batches production, and the primary separation stage reduced the volume of waste liquid above 86%. The NCA 177Lu product prepared by cyclic elution process meets the quality requirements.

[Objectives] When we measure submarine pressure hulls using a total station, it is essential to set several stations in order to complete the measurement of the whole cabin due to the complicated measuring environment. However, there are many restrictions related to the total station itself when moving stations, and it is also difficult to ensure measuring accuracy and satisfy the requirements of submarine measurement in complicated environments.[Methods] As such, a new station moving method is presented which can automatically establish standing relationships by measuring common points at every measuring position.[Results] This method can significantly improve accuracy and efficiency.[Conclusions] The experiment shows that the results of the new station moving method can meet sub-pixel precision and satisfy submarine measurement requirements with high accuracy.

In order to study the crack resistance of concrete lining in bored tunnel engineering, the test was carried out in a project. The results show that, the concrete prepared by fiber crack resistant composite materials has good anti-crack and antiseepage performance. The compressive strength of 7 d and 28 d age was basically the same as that of control concrete, the splitting tensile strength increased by 7.5% to 11.4%, the flexural strength increased by 11.6% to 12.3%, and the impermeability grade increased from P8 to P12. The monitoring data of the secondary lining concrete of the solid structure of the underground excavation tunnel project show that when the average thickness is 450 mm, the time of the steel formwork with the mold should be extended by 1~2 d or 1~2 d thermal insulation maintenance should be added after the removal of the formwork, so that the reduction rate of the first three days of the cooling stage is controlled within 5°C/d, which can further reduce the early temperature shrinkage. The maximum microstrain value of the solid structure about 104 µε after the early temperature correction, and it was reduced to -72 µε~-13 µε after two weeks. The early good crack resistance can effectively reduce the risk of non-structural shrinkage cracking. [ABSTRACT FROM AUTHOR]

The proton exchange membrane fuel cell (PEMFC) is an efficient and clean power generation technology with the characteristics of fast reaction kinetics and low start-up temperature. The current rapidly development of PEMFC technology is expected to be widely popularized. A brief overview of the development of PEMFC was given in recent years, starting from the core components of PEMFC. The core components were classified from the perspective of key materials. The research status and technical features of proton exchange membranes (PEM), catalysts and gas diffusion layers (GDL) were introduced in detail. The research methods, improvement methods and progress of each component were summarized, and the research direction and development trend of PEMFC were prospected. Based on various advantages in high temperature environments, PEM with short side chains and low equivalent weight values will continue to be the focus of research under high temperature and low humidity environments. PEMFC will further develop towards the situation of low Pt or even no Pt, and achieve water balance under humidification-free. [ABSTRACT FROM AUTHOR]

At present, the full implementation of negotiation and collaboration under the Paris Agreement faces new, key problems and severe challenges. Among these problems and challenges are: how to honor the principle of 'common but differentiated responsibilities' to facilitate comprehensive, balanced, and effective implementation of the key elements of the Paris Agreement such as adaptation, mitigation, finance, technology, capacity building, and transparency; how to uphold and maintain the status of China and other emerging countries as developing countries in light of the requirements of the UNFCCC and the historical responsibilities of these countries; how to assess the goal of limiting global temperature rise to 1.5 °C and what makes an equitable carbon mitigation pathway for diiferent types of countries; developed countries and developing countries have drastically diverging views on the carbon border adjustment measures for trading with developing countries proposed by many developed countries such as the European Union. The developed countries have demonstrated obvious intentions and actions to weaken and neglect the principle of 'common but diiferentiated responsibilities', to impose mitigation pressure on developing countries, to shift the responsibilities for emissions onto others, and to pass on the costs of mitigation. The game among diiferent types of countries and interest groups has become increasingly intense. In response, China should maintain its strategic focus, adhere to the goals and principles established by the Paris Agreement, stick to its strategic positioning as a developing country, solidify the strategic support from the developing world, and safeguard the legitimate rights and interests of developing countries. China has played a conducive role in facilitating the Paris Agreement and become an active participant, contributor and leader in global climate governance. China should continue to follow Xi Jinping's thought on ecological civilization and concept of building a community of shared future for mankind and actively lead the cooperation process in the construction of a global climate governance system characterized by equity, justice, ad win-win collaboration, ad promote compliance with the Paris Agreement. At the same time, China should accelerate the green, low-carbon, circular transformation of its economy, accelerate the coordinated governance of economy, environment, and climate change, and formulate and implement a long-term low-carbon development strategy. By the middle of the 21st century, while achieving the goal of building a great modern socialist country, China wiil achieve a deep decarbonization development path that is in line with the goal of limiting global temperature rise well below 2 °C and making an effort to keep it below 1.5 °C. [ABSTRACT FROM AUTHOR]

Objective To investigate the effect of different hardness of silicone rubber (SRs) on the proliferation and expression of α- SMA and Collagen Ⅰ in human dermal fibroblasts (HFBs), and study the role of autophagy in the process. Methods In this study, we prepared a series of SRs with different hardness by changing the ratio of liquid silica gel component A to B. The mechanical properties of SRs such as A-shore hardness, breaking elongation, water contact angle and surface morphology were measured. CCK-8 assay was used to study the proliferation of HFBs cultivated on the surface of these SRs. Then, 2 kinds of SRs with significant differences in hardness and cell proliferation were subjected, and Western blotting and ELISA were employed to detect the expression of autophagy markers, α-SMA and CollagenⅠin the HFBs after the treatment with autophagy inhibitor 3-MA and inducer rapamycin respectively. Results The proliferation of HFBs was obviously increased with the increase of SRs hardness (P < 0.05). Furthermore, the HFBs cultured on harder SRs surface had higher autophagy activity, and lower expression levels of α-SMA and Collagen Ⅰ when compared with the cells on softer SRs surface (P < 0.01). Conclusion The SRs hardness may affect the proliferation of HFBs by regulating autophagy. High hardness SRs promotes the proliferation of HFBs and inhibits the expression of α-SMA and CollagenⅠby enhancing autophagy activity.

17 β -Estradiol (E2), an important endocrine hormone in the mammalian body, participates in the regulation of the physiological functions of the reproductive system, mammary glands, bone, and cardiovascular system, among others. Paradoxically, despite the physiological actions of endogenous E2 (0.2-1.0 nmol/L), numerous clinical and experimental studies have demonstrated that high-dose E2 treatment can cause tumor regression and exert pro-apoptotic actions in multiple cell types; however, the underlying mechanism remains undescribed. In particular, little information of the cellular processes responding to the lethality of E2 is available. In the present study, we attempted to characterize the cellular processes responding to high-dose (μmol/L) E2 treatment using quantitative phosphoproteomics to obtain a better understanding of the regulatory mechanism of E2-induced cell death. First, the cell phenotype induced by high-dose E2 was determined by performing Cell Counting Kit-8 assay (CCK8), cell cytotoxicity analysis by trypan blue staining, and microscopic imaging on HeLa cells treated with 1-10 μmol/L E2 or dimethyl sulfoxide (DMSO) for 1-3 d. E2 inhibited cell proliferation and induced cell death in a dose- and time-dependent manner. Compared with the DMSO-treated HeLa cells, the cells treated with 5 μmol/L E2 for 2 d demonstrated >74% growth inhibition and approximately 50% cell death. Thus, these cells were used for quantitative phosphoproteomic analysis. Next, a solid-phase extraction (SPE)-based immobilized titanium ion affinity chromatography (Ti 4+ -IMAC) phosphopeptide-enrichment method coupled with data-independent acquisition (DIA)-based quantitative proteomics was employed for the in-depth screening of high-dose E2-regulated phosphorylation sites to investigate the intracellular processes responding to high-dose E2 treatment. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) identified over 10000 phosphorylation sites regulated by E2 and DMSO in HeLa cells. In comparison with the DMSO-treated cells, the cells treated with 5 μmol/L E2 showed 537 upregulated phosphorylation sites and 387 downregulated phosphorylation sites, with a threshold of p <0.01 and |log 2 (fold change)|≥1. A total of 924 phosphorylation sites on 599 proteins were significantly regulated by high-dose E2, and these sites were subjected to enrichment analysis. In addition, 453 differently regulated phosphorylation sites on 325 proteins were identified only in the E2- or DMSO-treated cell samples. These phosphorylation sites may be phosphorylated or dephosphorylated in response to high-dose E2 stimulation and were subjected to parallel enrichment analyses. Taken together, 1218 phosphorylation sites on 741 proteins were significantly regulated by high-dose E2 treatment. The functional phosphoproteins in these two groups were then analyzed using Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA) to determine the biological processes in which they participate and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database. Consistent with the cell-phenotype data, cell cycle-related proteins were highly enriched in the two groups of E2-regulated phosphoproteins ( p <0.05), indicating that high-dose E2 treatment can regulate cell proliferation. In addition, E2-regulated phosphoproteins were highly enriched in the cellular processes of ribosome biogenesis, nucleocytoplasmic transport, and messenger ribonucleic acid (mRNA) processing/splicing ( p <0.05), indicating that the activation of these processes may contribute to high-dose E2-induced cell death. These results further confirm that high-dose E2 treatment inhibits protein translation and induces cell death. Furthermore, the significant upregulation of multiple phosphorylation sites associated with epidermal growth factor receptor (EGFR) and mitogen-activated protein kinases (MAPKs) MAPK1, MAPK4, and MAPK14 by high-dose E2 indicates that the EGFR and MAPK signaling pathways are likely involved in the regulation of E2-induced cell death. These phosphorylation sites likely play vital roles in E2-induced cell death in HeLa cells. Overall, our phosphoproteomic data could be a valuable resource for uncovering the regulatory mechanisms of E2 in the micromolar range.

Protein-DNA interactions play essential roles in various biological events that determine the cell fate. Research on the molecular mechanism of protein-DNA interactions has helped elucidate diverse fundamental life processes, thereby providing theoretical guidance for establishing clinical treatment and screening potential drug of target diseases. Furthermore, well-known protein-DNA interactions have been utilized to develop advanced bioengineering and bioanalytical techniques, therefore providing robust technical support for related research. Hence, it is important to establish sensitive and rapid analytical methods to study protein-DNA interactions. High-performance capillary electrophoresis (CE) has been widely used in many research fields such as chemistry, life sciences, and environmental sciences, mainly due to its advantages including ultra-high separation efficiency, extremely low sample consumption, and short analysis time. For instance, affinity capillary electrophoresis (ACE) has become an important analytical tool for investigating molecular interactions. In this paper, we review the applications of ACE in studying protein-DNA interactions since it was first proposed in 1992, addressing previous significant work in this field. Three major aspects have been summarized in this review: (1) brief introduction to the development of ACE technique; (2) applications of ACE in the fundamental research on the molecular mechanism of protein-DNA interactions; and (3) applications of well-known protein-DNA interactions in CE-based detection of target molecules and reactions. In the first aspect, along with the concept and separation modes of ACE, general strategies to enhance the analytical ability of ACE are briefly introduced. In the second aspect, the applications of ACE in studying several important protein-DNA interactions involving transcription factors (e.g., GCN4), DNA repair proteins (e.g., UvrA, UvrB, and RecA), and methylated DNA-binding proteins (MBDs) are reviewed. In the third aspect, the applications of well-known molecular interactions (e.g., antigen-antibody, aptamer-target, etc.) to facilitate CE-based detection of target molecules (e.g., DNA adducts, DNA methylation, microRNA, single nucleotide polymorphism, etc.) and target reactions (e.g., DNA strand exchange) are addressed. Finally, we prospect and discuss the advancements of ACE that can be established in future studies. The following two aspects should be improved in future ACE analysis: (1) the advantages of extremely low volume consumption and short analysis time should be fully utilized to develop sensitive and high-throughput CE platforms for the assessment of rare biological samples and massive uncertain samples, respectively; (2) ACE should be combined with other advanced techniques, such as DNA sequencing and mass spectrometry, to rapidly screen and identify the precise interacting sites of unknown protein-DNA interactions.

Capillary electrophoresis (CE) has wide applications in many fields because of its extraordinary advantages, such as high efficiency of separation, high speed, and high throughput. However, the detection sensitivity is relatively low due to short detection window and short optical length. To improve the detection sensitivity, a number of on-line sample focusing and stacking modes have been developed, such as field-amplified sample stacking, pH gradient preconcentration, micellar electrokinetic capillary chromatography (MEKC), isotachophoresis (ITP). These on-line focusing techniques have been of intensive interest because of the ease of operation and simultaneous focusing during capillary electrophoresis separation. Here, we review the principle, advanced techniques and latest applications of on-line capillary electrophoresis focusing.

Objective: To investigate the substance basis and the mechanism of pseudoanaphylactoid reactions (PR) induced by Shuanghuanglian injection (SHLI)., Method: (1)The study of PR and the substance basis of PR of SHLI: ICR mice were divided into different test groups, the mice were intravenously injected with solutions of different concentration of SHLI, baicalin, forsythin, caffeotannic acid, positive control Compound 48/80 and normal sodium. All test substances were mixed with 0.4% Evans blue. The reaction and vascular permeability of the ears were observed and measured 30 min after SHLI injection. (2) The study of mechanisms: Mice were pretreated with an oral administration of Astemizol, intraperitoneal injection of cyclophosphamide 75 mg x kg(-1) or Compound 48/80 4 mg x kg(-1), then mice were intravenously injected with SHLI. At last, vascular permeability of the ears in pretreated groups was compared with SHLI treatment alone group., Result: SHLI of 300 mg x kg(-1) and 600 mg x kg(-1) caused obvious vascular hyperpermeability, but baicalin, forsythin and caffeotannic didn't cause vascular hyperpermeability in the ears. The Astemizol can decrease the degree of SHLI-induced vascular hyperpermeability of the ears in the mice. After intraperitoneal injected with cyclophosphamide, there was a slight decrease in the degree of SHLI-induced vascular hyperpermeability, but there was no marked changes in the degree of the SHLI-induced vascular hyperpermeability after the mice were pretreated with Compound 48/80., Conclusion: SHLI in clinic equivalent dose can cause vascular hyperpermeability. Baicalin, forsythin and caffeotannic may not result in the PR of SHLI. The mechanism of the PR maybe relate to that SHLI stimulates histamine release, the activation of leucocyte maybe take part in the SHLI-induced PR, too. Antihistamine drug can prevent the genesis of PR which induced by SHLI.

An ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the analysis of biomarker 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-OHdG) in deoxyribonucleic acid (DNA) was developed. The artificial oxidation of 2'-deoxyguanosine (dG) at numerous stages in the sample preparation bring a challenge to the accurate measurement of 8-OHdG in DNA. To avoid the artificial oxidation during the enzymatic digestion, desferrioxamine mesylate as a protectant was added into the mixtures. By utilizing YM-3 Centricon membrane (3 000 of relative molecular mass cut off), excess proteins in enzymatic solutions were effectively removed, allowing direct UPLC-MS/MS analysis. The UPLCMS/MS analysis showed a linear relationship between the peak areas and the amounts of 8-OHdG in the range of 17.6-1400 fmol, and the correlation coefficient was 0.9998. By using the developed method, the content of 8-OHdG in calf thymus DNA (CT DNA) was estimated about 12.9 +/- 2.35 (calculated as 8-OHdG/10(6) dG), which was consistent with the previous work. This method can also be applicable for the detection of 8-OHdG in DNA under various oxidative stresses.

DNA adducts is a very important class of biomarkers of human exposure to carcinogen, cancer risk assessment, and population susceptibility. There is a lack of a technology with a sufficient sensitivity to detect trace DNA adducts related to low environmental exposure levels. We attempt to develop a highly sensitive assay for the detection of DNA adducts by combining capillary electrophoresis-laser induced fluorescence (CE-LIF) with immunochemical recognition, or CE-LIF immunoassay. This review describes the recent research progress on CE-LIF instrument construction and the methodology of CE-LIF immunoassay for the detection of DNA adducts. The methodology study mainly involves the synthesis and characterization of the adduct containing DNA fluorescent probes, the interaction of DNA adducts and antibody, stabilization of trace DNA adducts-antibody complexes, and DNA-driven focusing.

The method for the determination of human thrombin by an aptamer was developed based on capillary electrophoresis (CE) with laser induced fluorescence (LIF) detection. The concentration of thrombin was calculated through the peak area of the thrombin-aptamer complex, which was separated and detected by CE-LIF. Because of the binding favorable G-quartet conformation potentially involved in the specific aptamer, it was assumed that monovalent and bivalent cations promoting the formation of a stable G quadruplex conformation in the aptamer may enhance the binding of the aptamer and thrombin. Therefore, the effects of various metal cations on the binding of human thrombin and the aptamer were investigated. The results showed that the cations like K+ and Mg2+ could not stabilize the affinity complex. The linear range, detection limit and reproducibility were measured. The linear range was 0.25 - 10 nmol/L (r2 = 0.991), and the detection limit of thrombin was 55.6 pmol/L. Regarding the advantages of high efficiency and rapid separation, low sample consumption, and high sensitivity, CE-LIF is a potential and powerful alternative to conventional immunoaffinity assays in clinical diagnostics.

In this paper is recommended a highly sensitive and reagent-safe method to determine plasma heamoglobin (FHb) in viscacha hemolytic test. The 2,4-dichlorophenol method (2,4-DCP) of Trinder reaction has been improved. The performance of 2,4-DCP is verified. The sensitivity of 2,4-DCP is 2.39 times that of phenol method. It is well used with run precision and day-to-day precision. The reaction color is stable. The reference value FHb is 1-36.7 mg/L. Sodium citric is an excellent anticoagulant liquid to keep erythrocyte. The 2,4-DCP method is neither carcinogenic nor poisonous;it is suitable for viscacha hemolytic test in clinical and biomedical engineering.