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Tuning metal–support interaction has been considered as an effective approach to modulate the electronic structure and catalytic activity of supported metal catalysts. At the atomic level, the understanding of the structure–activity relationship still remains obscure in heterogeneous catalysis, such as the conversion of water (alkaline) or hydronium ions (acid) to hydrogen (hydrogen evolution reaction, HER). Here, we reveal that the fine control over the oxidation states of single-atom Pt catalysts through electronic metal–support interaction significantly modulates the catalytic activities in either acidic or alkaline HER. Combined with detailed spectroscopic and electrochemical characterizations, the structure–activity relationship is established by correlating the acidic/alkaline HER activity with the average oxidation state of single-atom Pt and the Pt–H/Pt–OH interaction. This study sheds light on the atomic-level mechanistic understanding of acidic and alkaline HER, and further provides guidelines for the rational design of high-performance single-atom catalysts. Insights into the rational design of single-atom metal catalysts remains obscure in heterogeneous catalysis. Here, the authors establish the atomic-level structure–activity relationship for a wide-pH-range hydrogen evolution reaction through the electronic metal–support interaction modulation.

Prostate cancer is one of the most common cancers in men. This study was conducted to investigate the role of euchromatic histone lysine methyltransferase 2 (EHMT2) and endoplasmic reticulum protein 29 (ERP29) in the progression of radioresistance in prostate cancer. The expression of EHMT2 and ERP29 in prostate cancer cells and during the progression of radioresistance was detected using quantitative reverse transcription‐polymerase chain reaction and western blotting, and the interaction between EHMT2 and ERP29 was investigated. The proliferation of transfected cells under x‐ray irradiation was determined using the methyl thiazolyl tetrazolium and colony formation assays. Flow cytometry was used to analyze the apoptosis of the transfected cells under x‐ray irradiation. Nude mice were subcutaneously injected with prostate cancer (DU145) cells stably transfected with sh‐ERP29 or sh‐NC. The effect of ERP29 expression on radioresistance in nude mice was assessed by x‐ray irradiation. The expression of EHMT2 was upregulated and that of ERP29 was downregulated in prostate cancer cells during radioresistance progression. EHMT2 downregulation suppressed radioresistance in DU145 and androgen‐sensitive prostate cancer (LNCaP) cells. In irradiated DU145 cells, EHMT2 inhibition decreased the number of colonies and accelerated apoptosis. The transcription of ERP29 was suppressed by EHMT2 by upregulating H3K9me2 and downregulating H3K4me3, thereby regulating radioresistance in prostate cancer cells. In addition, the downregulation of ERP29 promoted the progression of radioresistance in prostate cancer cells in nude mice. EHMT2 promotes radioresistance in prostate cancer cells by repressing ERP29 transcription.

Background and purpose As endovascular thrombectomy (EVT) is time-dependent, it is crucial to refer patients promptly. Current referral modes include Mothership (MS), Drip and Ship (DS) and Drive the Doctor (DD). The purpose of this study was to investigate the influences of different referral modes on the clinical outcomes of patients with acute ischemic stroke after EVT.  Methods A total of 349 patients from 15 hospitals between April 2017 and March 2020 were enrolled. The primary outcomes include poor outcome (modified Rankin Scale score of 3 to 6), symptomatic intracranial hemorrhage transformation (sICH), mortality and cost. Regression analysis was used to assess the association of referral modes with poor outcome, sICH, mortality and cost in acute ischemic stroke patients. Results Among the 349 patients, 83 were in DD group (23.78%), 85 in MS group (24.36%) and 181 in DS group (51.86%). There were statistically significant differences in intravenous thrombolysis, onset-to-door time, onset-to-puncture time, puncture-to-recanalization time, door-to-puncture time, door-to-recanalization time, and cost among the DD, MS, and DS groups (59.04% vs 35.29% vs 33.15%, P <0.001; 90 vs 166 vs 170 minutes, P <0.001; 230 vs 270 vs 270 minutes, P <0.001; 82 vs 54 vs 51 minutes, P <0.001; 110 vs 85 vs 96 minutes, P =0.004; 210 vs 146 vs 150 minutes, P <0.001; 64258 vs 80041 vs 70750 Chinese Yuan, P =0.018). In terms of sICH, mortality and poor outcome, there was no significant difference among the DD, MS, and DS groups (22.89% vs 18.82% vs 19.34%, P =0.758; 24.10% vs 24.71% vs 29.83%, P =0.521; 64.47% vs 64.71% vs 68.51%, P =0.827). The results of multiple regression analysis indicated that there was no independent correlation between different referral modes regarding sICH ( OR MS : 0.50, 95%CI: 0.18, 1.38, P =0.1830; OR DS : 0.47, 95%CI: 0.19, 1.16, P =0.1000), mortality ( OR MS : 0.56, 95%CI: 0.19, 1.67, P =0.2993; OR DS : 0.65, 95%CI: 0.25, 1.69, P =0.3744) and poor outcome ( OR MS : 0.61, 95%CI: 0.25, 1.47, P =0.2705; OR DS : 0.53, 95%CI: 0.24, 1.18, P =0.1223). However, there was a correlation between MS group and cost ( β =30449.73, 95%CI: 11022.18, 49877.29; P= 0.0023). The multiple regression analysis on patients finally admitted in comprehensive stroke center (MS+DS) versus patients finally admitted in primary stroke center (DD) showed that DD mode was independently associated with lower costs ( β =-19438.86, 95%CI: -35977.79, -2899.94; P =0.0219). Conclusion There was no independent correlation between three referral modes and sICH, mortality, poor outcome correspondingly. Different referral modes can be implemented in clinical practice according to the situations encountered. Compared to MS and DS modes, DD mode is more economical.

The low-velocity impact behaviors of DP590/AA6061 self-piercing riveting (SPR) joints are studied at the impact energies of 5 J, 10 J, 20 J, 30 J, and room temperature (25 °C). The lap shear and fatigue tests, and the cross-sectional microscopies of joints are used to assess the mechanical property evolutions of the joints after low-velocity impact. The results show that the absorbed impact energies of SPR joints reach the critical value at an impact energy of 30 J, the exceeded impact energy causes crack failures in the sheets and decreases the interlocking performance of the joints. The static property and the absorbed energy of the SPR joints are reduced by 16% and 36% when the joints are impacted at 30 J, respectively. The low-velocity impacts do not change the failure forms of the joints, but significantly reduce the mechanical interlocking properties of the joints. The fatigue lives of the SPR joints are reduced due to low-velocity impact, and the impacted joints are more sensitive to cyclic loadings.

To investigate the low-speed impact response of the BR1200HS steel and AA6082 aluminum alloy self-piercing riveted (SPR) joint, low-speed impact tests with impact energies of 2.5 J, 5.0 J, 7.5 J, 10.0 J, 12.5 J, 15.0 J, 20.0 J, and 30.0 J were conducted utilizing a drop hammer impact tester. The results show that with the increased impact energy, the visual breakages of the SPR joints become more severe. The maximum impact energy the joints can sustain ranges from 10.0 J to 12.5 J. When the impact energy is less than 12.5 J, the contact force/energy–time curves show similar variations. Moreover, as the impact energy increases, total uptake energy value (Et), maximum uptake energy value (Ef), and maximum contact force (Fm) of the joints increase gradually. The low-speed impact energy has little effect on the maximum static tensile force of the impacted joints. However, the residual energy values decrease with the increase in impact energy. The tensile failure form of the joints is the pulling out of the rivets from the lower plates, and the low-speed impacts have no significant effect on the tensile failure form of the joints.

The first-line treatment options for high-risk prostate cancer (PCa) are definitive external beam radiotherapy (EBRT) with or without androgen deprivation therapy (ADT) and radical prostatectomy (RP) with or without adjuvant therapies. However, few randomized trials have compared the survival outcomes of these two treatments. To systematically evaluate the survival outcomes of high-risk PCa patients treated with EBRT- or RP-based therapy, a comprehensive and up-to-date meta-analysis was performed. A systematic online search was conducted for randomized or observational studies that investigated biochemical relapse-free survival (bRFS), cancer-specific survival (CSS), and/or overall survival (OS), in relation to the use of RP or EBRT in patients with high-risk PCa. The summary hazard ratios (HRs) were estimated under the random effects models. We identified heterogeneity between studies using Q tests and measured it using I2 statistics. We evaluated publication bias using funnel plots and Egger's regression asymmetry tests. Seventeen studies (including one randomized controlled trial [RCT]) of low risk of bias were selected and up to 9504 patients were pooled. When comparing EBRT-based treatment with RP-based treatment, the pooled HRs for bRFS, CSS, and OS were 0.40 (95% confidence interval [CI]: 0.24-0.67), 1.36 (95% CI: 0.94-1.97), and 1.39 (95% CI: 1.18-1.62), respectively. Better OS for RP-based treatment and better bRFS for EBRT-based treatment have been identified, and there was no significant difference in CSS between the two treatments. RP-based treatment is recommended for high-risk PCa patients who value long-term survival, and EBRT-based treatment might be a promising alternative for elderly patients.

Self-piercing riveting (SPR) is a suitable technology to join various materials and has attracted more attention in the automotive industry. In this work, the effects of forming parameters on the forming qualities and mechanical properties of B1500HS steel/AA5052 aluminum alloy SPR joints were analyzed. The results show that the sheet stack sequence has little influence on the peak tensile load and rigidity of SPR joints. When the steel sheet is placed on the aluminum sheet, the failure displacement, energy absorption, and ductility factor are, respectively, 2.77, 2.13, and 2.28 times larger than those of the joints with the aluminum sheet placed on the steel sheet. The SPR joints with steel sheets placed on aluminum sheets have better mechanical stability. Meanwhile, when the steel sheet is placed on the aluminum sheet, the fatigue life of the joint can be increased by about 98.4%, 88.3%, and 118.1%, respectively, under high, medium, and low fatigue loads. A joint with opposite riveting direction has the optimal fatigue performance and the fatigue life is 1.64 and 2.14 times those of the other two-rivet joints. Generally, the fatigue fractures of aluminum alloy sheets in SPR joints occurred in fatigue tests. The fatigue fracture of a joint with a steel sheet stacked on an aluminum sheet extends uni-directionally to the edge of the sheet from the riveting point, while a symmetric fatigue crack of aluminum occurs for joints with the opposite sequence. The distribution of fatigue cracks is related to fatigue load, and fatigue cracks mainly originate in the fretting wear area of the contact interface between the rivet leg, upper sheet, and lower sheet.

TC4 titanium alloy and AA6061 aluminum alloy are widely used in the transportation industry because of their excellent mechanical properties and lightweight. In this work, the TC4 titanium alloy was solution heat treated between 800 °C and 990 °C for 1 h, and water cooled to room temperature. The riveting and tensile tests at room temperature were conducted to evaluate the joint performance. The tensile strength and failure morphology were used to discuss the mechanical performance of joints. Solution heat treatment significantly improves the elongation, mechanical performance, and hardness of TC4 titanium alloy. Compared with the as-received material, the elongation of the treated TC4 titanium alloy is increased by 13% at the solution temperature of 900 °C, the tensile strength was added by 175 MPa at 930 °C, and the hardness was significantly increased. The optimal performance of the TC4 titanium alloy can be obtained at 930 °C. The tensile strength of the joint with the TC4 alloy solution heat treated at 930 °C is the highest of all joints. When the TC4 alloy was solution treated between 800 °C and 850 °C, the rivets were pulled from the AA6061. While at 900 °C and 930 °C, the AA6061 sheet was broken at the rivet. At 960 °C and 990 °C, the TC4 sheet was broken near the rivet. The crack size of TC4 titanium alloy gradually decreases from the rivet outward, and the crack spreads around the rivet. Severe friction can be found, which causes the peeling of the lower plate AA6061 alloy. The breaks of TC4 alloys were the plastic broken. The failure morphology of the TC4 alloy sheet is different under different solution heat treatment temperatures.

Head magnetic resonance imaging (MRI) performed on the third day of hospitalization showed a left cortical infarction [Figure 1D] and contrast-enhanced magnetic resonance angiography (CE-MRA) showed that the left internal carotid artery (ICA) was redeveloped with long segment stenosis, suspected of double lumen [Figure 1E and 1F]. In 1995, Frosst et al[1] showed that the substitution of C to T at nucleotide 677 in the MTHFR gene could lead to the replacement of encoded alanine by valine, thereby reducing the heat resistance and activity of the enzyme, affecting the methylation of Hcy and resulting in increased total Hcy level in plasma. [...]we have presented a special case of posterior circulation ischemia caused by acute occlusion of the left ICA dissection with right PTA.

Climate change and the global energy crisis have led to an increasing need for greenhouse gas remediation and clean energy sources. The electrochemical CO2 reduction reaction (CO2RR) is a promising solution for both issues as it harvests waste CO2 and chemically reduces it to more useful forms. However, the high overpotential required for the reaction makes it electrochemically unfavorable. Here, we fabricate a novel electrode composed of TiO2 nanoparticles grown in situ on MXene charge acceptor 2D sheets with excellent CO2RR characteristics. A straightforward solvothermal method was used to grow the nanoparticles on the Ti3C2Tx MXene flakes. The electrochemical performance of the TiO2/MXene electrodes was analyzed. The Faradaic efficiencies of the TiO2/MXene electrodes were determined, with a value of 99.41% at −1.9 V (vs. Ag/AgCl). Density functional theory mechanistic analysis was used to reveal the most likely mechanism resulting in the production of one CO molecule along with a carbonate anion through ∗CO, ∗O, and activated CO22− intermediates. Bader charge analysis corroborated this pathway, showing that CO2 gains a greater negative charge when TiO2/MXene serves as a catalyst compared to MXene or TiO2 alone. These results show that TiO2/MXene nanocomposite electrodes may be very useful in the conversion of CO2 while still being efficient in both time and cost.