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Based on the background of compliance control, this paper first introduces compliance control's significance, then analyzes the advantages and limitations of the current mainstream compliance control, including Impedance control, Force/position hybrid control, Modern, compliant control, Intelligent, compliant control. Moreover, this paper puts forward the limitations and the possible development direction of these schemes.

To help the forest managers calculate the carbon sequestration amount, we first give the calculation method of carbon sequestration amount of trees, and then establish a parameterized forest model according to the carbon sequestration amount, volume and the products of the Chinese fir in Huitong County, Hunan province, to facilitate our simulation study. Through dynamic planning, the problem of optimal carbon sequestration can be transformed into a linear programming problem. Then we obtain the management plan that maximizes carbon sequestration amount. By studying the management plan, we find that the age of the trees harvested is concentrated in the 25-30 years old, and the optimal harvesting plan will change when the parameters of the forest change.

Background: Glioma is the most common malignant intracranial tumor with high lethality. Despite surgery combined with chemoradiotherapy, the prognosis for patients with glioma remains poor. This is primarily due to acquired chemoradiotherapy resistance. Therefore, to improve the prognosis of glioma, further study into the mechanism of chemoradiotherapy resistance is needed. Objective: This study aimed to (1) evaluate the prognosis of patients with glioma by using a prognostic risk score model constructed by chemoradiotherapy resistance genes, (2) provide new targets and directions for precise treatment of glioma, and (3) discuss the tumor heterogeneity of tumor cells. Methods: According to therapy class and overall survival (OS), we identified 53 genes associated with glioma chemoradiotherapy resistance in The Cancer Genome Atlas Glioblastoma (TCGA GBM) database. Considering the improtant role of chemoradiotherapy resistance-related genes in the prognosis of glioma, we preliminarily screened and identified vital prognostic factors among these genes by using Cox regression model of absolute contraction and selection operators in the TCGA GBM lower-grade glioma (TCGA GBMLGG) dataset. Next, the heterogeneity of the chemoradiotherapy resistance-associated genes in different glioma cells was revealed by single-cell sequencing in the GSE117891 cohort. Results: A prognostic risk score model consisting of three genes (ARL4C, MSN, TNFAIP6) was constructed. The expression of this model was high in glioma neural progenitor cells (NPCs) and low in glioma oligodendrocytes. The OS rates were significantly lower in the high- vs low-risk group. Conclusion: Our 3 gene risk score complements current glioma diagnosis and provides a novel insight into chemoradiotherapy resistance mechanisms for the prognosis of patients with glioma.

Background: The six-transmembrane epithelial antigen of the prostate 3 (STEAP3) plays an essential role in iron uptake as an iron reductase. Previous studies found that STEAP3 may play crucial roles in tumorigenesis. However, a comprehensive pan‐cancer analysis of the prognosis and immunity of STEAP3 has not yet been reported. Methods: We performed a systematic analysis of the prognosis and immunity of STEAP3 in human pan-cancer. The data analysis and visualization were completed with R and Cytoscape. STEAP3 expression in cell lines and tissues was measured in multiple ways. Functional validation experiments were performed by shRNA knockdown inA498 and 786-O cell lines. Cell proliferation and invasive ability was detected by CCK-8 assay, transwell assay and wound healing assay. Results: In most tumor tissues, STEAP3 expression was remarkably upregulated and correlated with prognosis, particularly in clear cell renal cell carcinoma (ccRCC). Furthermore, STEAP3 expression was closely correlated with immune infiltrates and may induce recruitment and polarization of M2 macrophages in ccRCC. STEAP3 may be valuable for predicting responses to immune-checkpoint blockade (ICB) therapy. In addition, enrichment analysis results indicated that STEAP3 was positively related to immune-related pathways, P53 pathways and epithelial-mesenchymal transition (EMT). Finally, we demonstrated that STEAP3 was highly expressed in ccRCC tissues and might stimulate EMT via the downregulation of CDH1 in vitro in ccRCC. Conclusion: STEAP3 might function as a prognostic biomarker and immunotherapy response predictor in various cancers. Especially in ccRCC, STEAP3 is a new prognostic biomarker and exerts tumor-promoting function via stimulating the invasion and EMT and inducing recruitment and polarization of M2 macrophages.

To solve the problems of high energy consumed by the cooling system in the data center, this article puts forward a composite air conditioning system. The simulation platform for system operation performance is established, and the accuracy of the simulation platform is verified by experiments. The influence of operation parameters on system performance is analyzed by simulation. Finally, the optimal operation control parameters are determined. The results show that the system can adjust the condenser wind speed and the refrigerant pump operating frequency to meet the cooling requirements and solve the problem of low evaporation temperature in the heat pipe. The evaporative cooling effectively expands the working range of the heat pipe mode and raises the upper limit of outdoor temperature from 8 °C to 15 °C. In the vapor compression mode, when the ambient temperature is lower than 26 °C, the performance of the air-cooled mode is better than that of the evaporative-cooled mode. The condensation temperature can be ensured within a reasonable range by adjusting the condenser cooling wind speed and the compressor frequency. When the outdoor temperature is not less than 26 °C, the evaporative cooling can effectively improve the operation performance

Carburizing treatment can improve the carbon content of the workpiece material, and obtain higher contact fatigue strength, bending fatigue strength, as well as higher surface hardness. After carburizing, the existence of carbon atoms can hinder the adsorption and diffusion of hydrogen, thus reducing the hydrogen embrittlement. First-principles plane wave calculations based on spin-polarized density-functional theory (DFT) and the generalized gradient approximation (GGA) have been used to study the adsorption and permeation of hydrogen on iron in the bulk with carbon interstice solid solution and carbon substitution solid solution. Considering that hydrogen diffusion is faster in martensitic tissue, bcc-Fe structure is selected for the model. The results show that the hydrogen diffusion rate Di in the interstice solid solution is higher than Ds in the substitution solid solution. The formation of substitution solid solution is promoted by more vacancies in the lattice. When the vacancy is occupied by carbon atoms, the hydrogen diffusion rate is reduced. This phenomenon is more obvious for Fe48C16 structure with higher carbon ratio. Besides, charge density diagram and state density analysis are also consistent with this conclusion. Therefore, during carburizing, Increasing the content of carbon and carbon substituted solid solution can reduce the penetration of hydrogen in the material.

This study aims to investigate the hydrogen-induced cracking behavior of the cylinder of 4130X hydrogen storage vessel in a 45 MPa high-pressure hydrogen environment under the synergistic influence of hydrogen and crack depth. Firstly, finite element analysis was performed via a modified hydrogen diffusion/plasticity coupled model to study the coupling behavior of hydrogen diffusion and plastic deformation in a hydrogen storage vessel with a crack. Then we used the modified hydrogen diffusion/plasticity coupled model to study the effect of crack depth on the hydrogen-induced cracking behavior in the hydrogen storage vessel. Results show that the hydrogen is mainly concentrated in the trap at the crack tip of the vessel, and the crack tip is always the position with the highest total hydrogen concentration. The distribution of plastic strain and trap hydrogen concentration on the crack surface is small along the axial direction of the cylinder, but large along the radial direction of the cylinder. With the increase of the initial crack depth, the pressure difference corresponding to the crack propagation from radial direction to unstable propagation and the depth of the crack propagation show a decreasing trend, and the hydrogen pressure of unstable propagation also decreases gradually. The greater the depth of cylinder crack, the more difficult it is to prevent cylinder failure.

The late Quaternary shallow-water carbonates have been altered by a variety of diagenetic processes, and further influenced by high-amplitude global and regional sea level changes. This study utilizes a new borehole drilled on the Yongxing Island, Xisha Islands to investigate meteoric diagenetic alteration in the late Quaternary shallow-water carbonates. Petrographic, mineralogical, stable isotopic and elemental data provide new insights into the meteoric diagenetic processes of the reef limestone. The results show the variation in the distribution of aragonite, high-Mg calcite (HMC) and low-Mg calcite (LMC) divides the shallow-water carbonates in Core SSZK1 into three intervals, which are Unit I (31.20–55.92 m, LMC), Unit II (18.39–31.20 m, aragonite and LMC) and Unit III (upper 18.39 m of core, aragonite, LMC and HMC). Various degrees of meteoric diagenesis exist in the identified three units. The lowermost Unit I has suffered almost complete freshwater diagenesis, whereas the overlying Units II and III have undergone incompletely meteoric diagenesis. The amount of time that limestone has been in the freshwater diagenetic environment has the largest impact on the degree of meteoric diagenesis. Approximately four intact facies/water depth cycles are recognized. The cumulative depletion of elements such as strontium (Sr), sodium (Na) and sulphur (S) caused by duplicated meteoric diagenesis in the older reef sequences are distinguished from the younger reef sequences. This study provides a new record of meteoric diagenesis, which is well reflected by whole-rock mineralogy and geochemistry.

Glioma is the most common malignant intracranial tumor with high lethality. Despite surgery combined with chemoradiotherapy, the prognosis for patients with glioma remains poor. This is primarily due to acquired chemoradiotherapy resistance. Therefore, to improve the prognosis of glioma, further study into the mechanism of chemoradiotherapy resistance is needed.This study aimed to (1) evaluate the prognosis of patients with glioma by using a prognostic risk score model constructed by chemoradiotherapy resistance genes, (2) provide new targets and directions for precise treatment of glioma, and (3) discuss the tumor heterogeneity of tumor cells.According to therapy class and overall survival (OS), we identified 53 genes associated with glioma chemoradiotherapy resistance in The Cancer Genome Atlas Glioblastoma (TCGA GBM) database. Considering the important role of chemoradiotherapy resistance-related genes in the prognosis of glioma, we preliminarily screened and identified vital prognostic factors among these genes by using the Cox regression model of absolute contraction and selection operators in the TCGA GBM lower-grade glioma (TCGA GBMLGG) dataset. Next, the heterogeneity of the chemoradiotherapy resistance-associated genes in different glioma cells was revealed by single-cell sequencing in the GSE117891 cohort.A prognostic risk score model consisting of three genes (ARL4C, MSN, TNFAIP6) was constructed. The expression of this model was high in glioma neural progenitor cells (NPCs) and low in glioma oligodendrocytes. The OS rates were significantly lower in the high- vs. low-risk group.Our 3 gene risk score complements the current glioma diagnosis and provides a novel insight into chemoradiotherapy resistance mechanisms for the prognosis of patients with glioma.

To improve energy efficiency of data centers, an air conditioning system for the concept of demand-based on cooling was proposed. This system combines a heat pipe cooling cycle and a vapor compression cooling cycle. Besides, the evaporative condenser is used to further utilize the natural cooling source, and the evaporator is put into the rack to realize on-demand cooling. A mathematical model was established to perform simulations of the system. The results showed that the energy consumption of compressor and pump reduce with the rising of outdoor unit air flow and evaporator inlet temperature. The coefficient of performance (COP) was selected as a reference index. When the cooling capacity is 8000 W, 6400 W and 4800 W, the optimal outdoor unit air flow of the heat pipe mode is 2000 m3/h, 1400 m3/h and 800 m3/h, respectively, and that of the vapor compression mode is 4000 m3/h, 3600 m3/h and 2400 m3/h, respectively. With the rising of evaporator inlet temperature from 29 °C to 41 °C under rated conditions, the heat pipe mode COP increased by 30.11%, 13.52% and 6.30%, respectively, and the vapor compression mode COP increased by 74.65%, 82.12% and 90.97%, respectively.

To solve the problems of single heat source heat pump systems in severe cold regions, a dual-source hybrid heat pump unit (DSHHPU) is proposed. The mathematical models of the DSHHPU when charging R134a or its alternative refrigerants R32, R290 and R600a were established respectively, and the performance was simulated and analysed. The results showed that the four refrigerants have different performance characteristics in different aspects. In heat pipe mode, the heating capacity and evaporating pressure of R32 are 36.94% and 59.94% higher than those of R134a. The heating capacity and evaporating pressure of R290 are 5.73% and 22.99% lower than those of R134a. The heating capacity and evaporating pressure of R600a are 43.29% and 68.08% lower than those of R134a. In vapour compression heating mode, the discharge temperature of R32, R290 and R600a are 184.88, 72.98 and 66.44% of that of R134a. The coefficient of performance (COP) of R32, R290 and R600a are 72.65, 111.59 and 117.94% of that of R134a. Finally, the effects of radiation intensity and ambient temperature on key performance parameters of the different refrigerants were analysed. The research results provide a reference for research on refrigerant replacements for multi-heat source composite heat pump systems.

Renal lymphangiogenesis is a new field of international nephrology in recent years and plays an important role in the progression of chronic renal disease. CD137 was originally described as a surface molecule present on activated T and NK cells and detected on hypoxic endothelial cells and inflamed blood vessels, but its function on lymphatic endothelial cells remains unclear. We investigated the relationships among CD137, lymphangiogenesis and macrophages, which are involved in interstitial fibrosis. Similar to other chronic inflammatory diseases, we found lymphangiogenesis and expression of CD137 in the renal tissue of patients with IgA nephropathy. CD137-positive lymphatic vessels were involved in the development process of IgA nephropathy and positively correlated with serum creatinine, serum urea nitrogen, serum uric acid, and urinary 24 h total protein. The expression of these indicators was negatively correlated with eGFR, plasma albumin, and HB. In mouse models of UUO, we verified that CD137 expression was significantly elevated during lymphangiogenesis and that its ligand CD137L was released by macrophages after VEGF-C stimulation in the kidney. In vitro, recombinant CD137L significantly enhanced LEC proliferation, migration and tube formation, and these effects were inhibited by CD137 siRNA. Mechanistically, the CD137L interaction with CD137 induced the transition from LC3-I to LC3-II and the expression of Atg5, Atg7, Atg12 and p62 proteins by activating the PI3K/AKT/mTOR pathway to promote autophagy. Knockdown of Atg5 and Atg7 blocked CD137L-induced autophagy. Thus, we propose that CD137L secretion by macrophages interacts with CD137 on lymphatic endothelial cells to prompt lymphangiogenesis in the kidney, which further drives fibrogenic responses. Our findings suggest that inhibition of the CD137-CD137L pathway is a novel therapeutic approach for obstructive nephropathy.

N-acetylcysteine has been widely used as a nutritional supplement and drug in humans for its antioxidant properties. The complement activation fragment C5a is a strong proinflammatory molecule that mediates cell adhesion, chemotaxis, and the complex biological functions. However, the effect of NAC on the C5a, and the relationship of those two with cisplatin-induced acute kidney injury are unknown. In cisplatin induced AKI mouse model, mice with NAC administration had a marked improvement in renal function (BUN and Cr), decreased pathological damage, reduced inflammation, and alleviated renal oxidative stress. Furthermore, C5a and C5aR expression in the cisplatin-treated group was notably increased compared with the control group, and this increase could be significantly inhibited by NAC. In addition, neutrophils coexpressed distinctly with C5aR, and the number of infiltrating neutrophils (MPO+ly6G+) and inflammatory factors decreased with NAC treatment in the cisplatin-treated group. Overall, these data demonstrate that NAC could ameliorate cisplatin-induced nephrotoxicity in mice and the protective effects may be conducted by inhibiting the activation of kidney inflammation and the complement system.

Abnormal oil casing pressure appeared in the process of test production of multiple Ultra-Deep Gas Wells in Tarim Basin. The super 13Cr oil pipe string was used to analyze the causes of pipe string failure in view of the oil casing channeling well during the test and blowout period. The construction process of the well was analyzed in detail. Combined with the review of the operation flow and the detection of fracture string material and fracture morphology, the causes of pipe string fracture were analyzed and calculated in detail. Through field investigation, analysis and calculation, it was found that the main cause of cracking of super 13Cr tubing in this well is the decrease of vibration natural frequency caused by excessive fluid velocity in pipe and too long span of pipe string. At the same time, the mixed failure of stress corrosion cracking and stress load interaction occurred in Cl−1 environment and other corrosion environments.

With the increasing demand for new technologies in HPHT (high pressure high temperature) wells, more and more attention has been paid to the system of technical qualifications. Most established norms, standards and recommended practices are written in prescribed formats, setting out methods, procedures and acceptance criteria for product design, manufacture and testing. However, established norms, standards or recommended practices may not adequately cover new technologies or applications. The technical qualification system is established in this paper, which can identify the potential failure modes and some activities in order to control the uncertainties and increase confidence of using new technology. A risk-based technical qualification system is used to assess non-traditional operations. It includes following seven main steps: system breakdown, technology assessment and classification, technical novelty, failure model and risk analysis, risk-based qualification planning and participation level development. The core of technical qualification system is to understand the ways and causes of system failure, and to carry out corresponding activities to provide evidence that the system will not fail. Through the technical identification process, the detailed equipment/operation specifications and identification requirements have been formulated. Different levels of participation are assigned for each eligibility activity, depending on the hazard and risk. It is proved that the application of the technical qualification principle in the systematic evaluation and control of the risks of new technologies or new applications is successful. In HPHT wells in particular, operators can move from a reactive approach to a proactive approach.

In order to solve the problems of uneven air supply and mixing of cold and hot airflow in the data center at present. This paper proposes a cabinet with on-demand cooling function, introduces the structure and working principle of it, establishes a simulation experiment platform for simulation calculation, and studies the influence of different factors on the cooling effect. The results show that compared with the traditional cooling method, the cooling effect of this cabinet is better, the average temperature of the servers is reduced by 7.89 K; the cooling effect can be improved by increasing the air intake volume and reducing the air inlet temperature, and the influence of air temperature on the cooling effect is greater than that of air volume: every 2 K increase in inlet air temperature, the minimum intake air volume will be increased by up to 600 m3/h.

Aiming at the large energy consumption of the air-conditioning system in the data center, an evaporative cooling composite air-conditioning system was proposed. This paper analyzes the impact of outdoor airflow on system performance parameters under different cooling requirements through system modeling and simulation. The results show that the increasing airflow of the outdoor unit increases the energy consumption of the fan, but helps to reduce the power consumption of the compressor and the refrigerant pump. Taking COP value as objective function, the optimum outdoor airflow is obtained. Under the 100, 80, and 60% rated cooling capacity of this system, the optimal outdoor airflow in the heat pipe mode are 2000, 1400, and 800 m3/h and in the vapor compression mode are 4000, 3600, and 2400 m3/h, respectively.

Grape seed proanthocyanidin extract (GSPE) has been reported to exhibit a variety of protective effects, such as antioxidant, anti-atherosclerosis and other pharmacological effects. As a member of the complement system, complement component 3 (C3) deposition in the glomerulus is recognized as an important causative mediator of various kidney diseases. In this study, we aimed to identify the effect of GSPE on C3 in the chronic kidney fibrosis and evaluate the possible mechanism. We observed that administration of GSPE relieves inflammation and chronic renal fibrosis in mouse models of UUO. GSPE inhibited C3 secreted by macrophages to relieve renal interstitial inflammation. In vitro, we found that C3 stimulated HMGB1 translocation form nucleus to cytoplasm and promote the expression of pro-inflammatory cytokines including TGF-β1 in primary renal tubular epithelial cells (PTEC), which could be inhibited by GSPE. Meanwhile, GSPE could also decreased HMGB1-induced EMT of PTEC through suppresses the HMGB1/TLR4/p65/TGF-β1 pathway. In addition, the myofibroblast activation was inhibited by GSPE via TGF-β1/Smad2/3 signaling pathways in normal rat kidney fibroblast (NRK-49F) cells. Overall, these observations provide that GSPE alleviates renal fibrosis by inhibiting the C3/HMGB1/TGF-β1 pathway and could thus lead to find the potential therapy for the suppression of renal fibrosis.

An evaporative cooling composite air conditioning system aimed at enhancing energy efficiency of data centers was proposed. Furthermore, the mathematical models on the base of the operation characteristics of the system were established. After verification by experiment, the energy saving performance of the system under different climatic conditions was investigated. The simulation results showed that the annual performance factor (APF) values are 5.31, 5.02, 4.75 and 4.50, respectively in severe cold zone-Shenyang (123.38E, 41.8N), cold zone-Beijing (116.30E, 39.9N), hot summer & cold winter zone-Nanjing (118.78E, 32.0N) and mild zone-Kunming (102.72E, 25.1N). The power usage effectiveness (PUE) values are below 1.40, the system has good energy saving advantages in different locations. After a water-cooled heat exchanger is used in the evaporative condenser, the APF values improve in all the four cities. The use of water-cooled heat exchanger is beneficial to further enhance energy saving of the system. A case study based on the system elaborates that it is feasible for energy saving of data centers in various climatic zones.

Maximizing utilization of natural cold energy has become the key to reduce the energy consumption of data center air-conditioning system. A new type of evaporative condenser with water-cooled condensation is proposed and used in the data center composite air conditioning system. The model of air conditioning system is established and verified by the experimental platform. The simulation results show that although the coefficient of performance (COP) of the evaporative cooling heat pipe mode is reduced by 0.88% on average by the proposed evaporative condenser, the upper limit of temperature operation of this mode is raised from the original 15 °C to 17 °C. The heat pipe mode has been extended throughout the year, and the advantages of energy saving have been fully utilized. For the evaporative cooling vapor compression mode. The proposed evaporative condenser can reduce the energy of the composite system, and the COP is increased by 9.82% on average, showing high operating performance.

Complement synthesis in cells of origin is strongly linked to the pathogenesis and progression of renal disease. Multiple studies have examined local C3 synthesis in renal disease and elucidated the contribution of local cellular sources, but the contribution of infiltrating inflammatory cells remains unclear. We investigate the relationships among C3, macrophages and Th17 cells, which are involved in interstitial fibrosis. Here, we report that increased local C3 expression, mainly by monocyte/macrophages, was detected in renal biopsy specimens and was correlated with the severity of renal fibrosis (RF) and indexes of renal function. In mouse models of UUO (unilateral ureteral obstruction), we found that local C3 was constitutively expressed throughout the kidney in the interstitium, from which it was released by F4/80+macrophages. After the depletion of macrophages using clodronate, mice lacking macrophages exhibited reductions in C3 expression and renal tubulointerstitial fibrosis. Blocking C3 expression with a C3 and C3aR inhibitor provided similar protection against renal tubulointerstitial fibrosis. These protective effects were associated with reduced pro-inflammatory cytokines, renal recruitment of inflammatory cells, and the Th17 response. in vitro, recombinant C3a significantly enhanced T cell proliferation and IL-17A expression, which was mediated through phosphorylation of ERK, STAT3, and STAT5 and activation of NF-kB in T cells. More importantly, blockade of C3a by a C3aR inhibitor drastically suppressed IL-17A expression in C3a-stimulated T cells. We propose that local C3 secretion by macrophages leads to IL-17A-mediated inflammatory cell infiltration into the kidney, which further drives fibrogenic responses. Our findings suggest that inhibition of the C3a/C3aR pathway is a novel therapeutic approach for obstructive nephropathy.