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Effects of pre-treatment (either pre-deformation or composed of pre-aging and pre-deformation prior to aging) on the dislocation morphologies and subsequent precipitation, corrosion behaviors, and mechanical properties of a novel Al-8.26Zn-1.95Mg-1.89Cu-0.08Sc-0.17Zr (wt.%) alloy were investigated. Pre-existing Al3(Sc, Zr) dispersoids can pin dislocations induced by pre-deformation before aging to form dislocation cells and cell walls. As a result, bimodal microstructures are formed during the subsequent aging process, with coarse precipitates dispersed along dislocation walls and fine precipitates inside dislocation cells. Meanwhile, dislocations pinned by Al3(Sc, Zr) dispersoids nearby grain boundaries inhibit the diffusion of solutes towards grain boundaries, which can modify grain boundary features by decreasing the potential difference between grain boundaries and grain interiors, and reducing precipitation-free zone width and grain boundary precipitate size. In particular, pre-aging prior to pre-deformation makes the dislocation distribution more uniform, which increases the volume fraction of nanoprecipitates without significant coarsening and further improves the grain boundary characteristics. Compared with the traditional T74 treated sample, these multiple microstructures significantly enhance the corrosion resistance of the alloy with less strength degradation. This study offers novel insights into the strengthening and corrosion mechanisms of pre-treated Al–Zn–Mg–Cu alloys with Zr and Sc microalloying.

Abstract Background New oral anticoagulants (NOACs) have been becoming prevalent in recent years and are increasingly used in the treatment of port vein thrombosis. The difference of the efficacy and safety between rivaroxaban and dabigatran remains unclear in the treatment of cirrhotic patients with acute portal vein thrombosis (PVT). Methods This retrospective study included all consecutive cirrhotic patients with acute portal vein thrombosis in our institute from January 2020 to December 2021. The patients received oral anticoagulation with rivaroxaban or dabigatran. The demographic, clinical, and imaging data of patients were collected. The diagnosis of acute PVT was confirmed by imaging examinations. The severity of liver cirrhosis was assessed using Child–Pugh score and Model for End-Stage Liver Disease (MELD) score. Outcomes included recanalization (complete, partial, and persistent occlusion), liver function, bleedings, and survival. The log-rank test was used to compare Kaplan–Meier distributions of time-to-event outcomes. The Cox proportional hazards model was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs). Results A total of 94 patients were included, 52 patients (55%) received rivaroxaban and 42 (45%) with dabigatran. The complete and partial recanalization of PVT was observed in 41 patients. There was no significant difference in complete recanalization, partial recanalization, and persistent occlusion between the two groups. With multivariate analysis, D-dimer (HR 1.165, 95% CI 1.036–1.311, p = 0.011) was independent predictors of complete recanalization. The Child–Pugh score (p = 0.001) was significantly improved in both two groups after anticoagulation, respectively. However, there was no difference between the two groups. The probability of survival was 94%, 95% in the rivaroxaban and dabigatran groups (log-rank p = 0.830). Major bleedings were reported in 3 patients (6%) in rivaroxaban group and 1 patient (2%) in dabigatran group (p = 0.646). Six patients (12%) in rivaroxaban group experienced minor bleeding, and five (12%) from dabigatran group (p = 0.691). Conclusions The efficacy and safety were comparable between rivaroxaban and dabigatran in the treatment of cirrhotic patients with acute portal vein thrombosis. And D-dimer can contribute to the prediction of PVT recanalization in cirrhotic patients.

The microstructure and mechanical properties of as-cast Al-10Ce-3Mg-xZn (x = 0, 1, 3, 5 wt.%) alloys were systematically investigated, with a focus on the effect of Zn on the Al11Ce3 reinforcing phase in the alloy. The results showed that the Al-10Ce-3Mg alloy consists of α-Al, a Chinese-script Al11Ce3 eutectic phase, and a massive Al11Ce3 primary phase. With the addition of Zn content, most of the Zn atoms are enriched in the Al11Ce3 phase to form the acicular-like Al2CeZn2 phase within the Al11Ce3 phase. Increasing the Zn content can increase the volume fraction of the Al11Ce3 phase. Compared to the alloy without Zn addition, the microhardness and elastic modulus of the Al2CeZn2-reinforced Al11Ce3 phase in the alloy with 5 wt.% Zn increased by 18.9% and 9.0%, respectively. Moreover, the room-temperature mechanical properties of Al-10Ce-3Mg alloys were significantly improved due to the addition of Zn element. The alloy containing 5 wt.% Zn had the best tensile properties with an ultimate tensile strength of 210 MPa and a yield strength of 171MPa, which were 21% and 77% higher than those of the alloy without Zn, respectively. The alloy containing 5 wt.% Zn demonstrated a superior retention ratio of tensile strength at 200–300 °C, indicating that the alloy has excellent heat resistance. The improvement in the mechanical properties is primarily attributed to second-phase strengthening and solid solution strengthening.

IntroductionSurgeons may experience physical and mental health problems because of their jobs, which may lead to chronic muscle damage, burnout, or even withdrawal. However, these are often ignored in camera-holder assistants during laparoscopic surgery. We aimed to analyze the differences between operating surgeons and camera-holder assistants.MethodsFrom January 1, 2022, to December 31, 2022, a cross-sectional survey was conducted to evaluate the muscle pain, fatigue, verbal scolding, and task load for operating surgeons and camera-holder assistants. The Nordic Musculoskeletal Questionnaire, the Space Administration Task Load Index, and the Surgical Task Load Index (SURG-TLX) were combined in the questionnaire.Results2,184 operations were performed by a total of 94 operating surgeons and 220 camera assistants. 81% of operating surgeons and 78% of camera-holder assistants reported muscle pain/discomfort during the procedure. The most affected anatomic region was the shoulders for operating surgeons, and the lower back for camera-holder assistants. Intraoperative fatigue was reported by 41.7% of operating surgeons and 51.7% of camera-holder assistants. 55.2% of camera-holder assistants reported verbal scolding from the operating surgeons, primarily attributed to lapses in laparoscope movement coordination. The SURG-TLX results showed that the distributions of mental, physical, and situational stress for operating surgeons and camera-holder assistants were comparable.ConclusionLike operating surgeons, camera-holder assistants also face similar physical and mental health impairments while performing laparoscopic surgery. Improvements to the working conditions of the camera-holder assistant should not be overlooked.

IntroductionRecent studies have indicated that the dosage of LMWH in patients with specific weights may be controversial. Therefore, we conducted a meta-analysis to explore an appropriate dosage of LMWH for the prevention and treatment of venous thromboembolism (VTE) in patients with obesity.Materials and methodsWe searched the PubMed, EMBASE, and Cochrane Library databases up to July 23, 2022. Study selection, bias analysis, and information extraction were performed by three independent reviewers. The occurrence or recurrence of VTE and bleeding events were the primary outcomes we assessed.ResultsEleven studies (a total of 6266 patients) were included in the prevention group, and 6 studies (a total of 3225 patients) were included in the treatment group. For VTE prophylaxis, compared with the standard-dosage group, the high-dosage group had a lower incidence of VTE (OR: 0.47, 95% CI: 0.27-0.82, P=0.007) and a similar incidence of bleeding events (OR: 0.86, 95% CI: 0.69-1.08, P=0.020). For VTE therapy, compared to the standard-dosage group, the reduced-dosage group had a similar incidence of VTE recurrence (OR: 0.86, 95% CI: 0.11-6.84, P=0.89) but a lower incidence of bleeding events (OR: 0.30, 95% CI: 0.10-0.89, P=0.03).ConclusionIn patients with obesity, increasing the dosage of LMWH is a more appropriate option for the prevention of VTE. Due to the limited evidence, reducing the therapeutic dosage of LMWH requires careful consideration. Larger-scale, well-designed randomized controlled trials are necessary.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?, identifier ID=CRD42022298128.

In this study, the T85-treated Al-3.78Cu-1.17Li-0.7 Mg-0.32Ag-0.25Mn-0.33Zn-0.12Zr alloy thermally exposed at a series of temperatures (100–300 °C) for 100 h, 500 h, and 1000 h was systematically investigated. The results show that the thermal stability of the alloy is more closely correlated with thermal exposure temperature than with exposure duration. Excellent thermal stability in strength is obtained below 150 °C, which can be linked to the diameter and number density of T1 (Al2CuLi) precipitates continually increasing with a thickness less than 2 nm. However, the widened precipitation-free zones (PFZs) associated with continuous grain boundary precipitates (GBPs) benefit intergranular fracture, contributing to a decrease in toughness and elongation. In the window of 175–200 °C, T1 precipitates tend to thicken and are gradually substituted by coarse θ′-Al2Cu and S-Al2CuMg with elevating temperature. Simultaneously, the continuous GBPs transverse to discrete circle-like shapes, and thus intergranular ductile fracture becomes dominant. Therefore, the related hardness and strength decrease, while the electrical conductivity and toughness are the opposite. At temperatures over 250 °C, thermal exposure can reduce the dislocation density and dissolve T1 phases to form T2-Al6Cu(Li, Mg)3 and cubic C phases, leading to a dramatic decrease in strength and toughness.

In this study, the effects of the combined addition of CeLa and GdY on the microstructure and mechanical properties of as-cast Al-4Cu-1Mn alloys were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and tensile testing. The results show that the minor addition of CeLa and GdY leads to a refinement of grain size. The addition of CeLa results in the formation of supersaturated vacancies in the Al matrix, whereas the addition of GdY leads to a decrease in the precipitation temperature of the Al2Cu phase. The combined CeLa and GdY additions can significantly increase ultimate tensile strength (UTS) while losing only a small amount of elongation (EL). Compared with the unmodified alloy, the grain size and SDAS of the alloy (0.2 wt.% CeLa + 0.1 wt.% GdY) were diminished by 67.2% and 58.7%, respectively, while maximum hardness and UTS rose by 31.2% and 36.9%, respectively.

The Al-Mg-Li alloy is ideal for ultra-lightweight aircraft components, and its further performance improvement is of great interest in the aerospace industry. In this study, the effects of various beryllium (Be) additions (Be-free, 0.1, 0.25, 0.50 wt.%) on the microstructure, mechanical, and corrosion performance of the Al-Mg-Li alloys were systematically investigated. The optimal tensile property was obtained in the alloy which added 0.1 wt.% Be with an ultimate tensile strength (UTS), yield strength (YS), and elongation (El) of 530 MPa, 370 MPa, and 9.2%, respectively. Trace Be addition promotes the grain refinement of the as-cast alloy ingot and contributes positive effects to the recrystallization, bringing improvement of the tensile property. Meanwhile, the best anti-corrosion behavior is also presented at 0.1 wt.% Be is added, due to its potential to reduce the width of precipitates free zone (PFZ). As the Be content increases to an excessive level, the comprehensive performance decreases. Therefore, it is strongly recommended that adding trace Be elements into Al-Mg-Li alloys has a positive effect on the comprehensive service performance.

The deformation behavior and microstructure evolution of Al–5.06Mg–1.67Li–0.51Zn alloy was investigated under hot compression at a range of temperature from 623 K to 753 K and different strain rates of 0.01–10 s−1. The constitutive equation on hyperbolic sine function and the hot processing maps were established. The hot deformation characteristics of the alloy were studied by optical microscopy and electron backscatter diffraction analysis. It was indicated that the flow stress decreased with the increase of the deformation temperature and the decrease of the strain rate. After the flow stress reached the peak stress at the strain rate of 0.01 s−1, the effects of dynamic recrystallization and work hardening alternated with each other. Meanwhile, the dynamic balance was reached between them, where the flow stress curves appeared periodic fluctuations. With decreasing the lnZ value, the proportion of low-angle grain boundaries in the deformed specimens decreased, and the average misorientation of each grain showed the opposite trend. The low-angle grain boundaries transformed to the high-angle grain boundaries. The migration of high-angle grain boundaries, as well as the merging of sub-grains, was more pronounced. The main dynamic softening mechanism changed from particle-stimulated dynamic recrystallization to geometric dynamic recrystallization and continuous dynamic recrystallization due to the reduced lnZ.

Background: Sepsis induces GAS5 expression in the vascular endothelium, but the molecular mechanism is unclear, as is the role of GAS5 in sepsis. Methods and results: We observed that GAS5 expression in the endothelium was significantly upregulated in a sepsis mouse model. ChIP-PCR and EMSA confirmed that the oxidative stress (OS)-activated MiT–TFE transcription factor (MITF, TFE3, and TFEB)-mediated GAS5 transcription. In vitro, GAS5 overexpression attenuated OS and inflammation in endothelial cells (ECs) while maintaining the structural and functional integrity of mitochondria. In vivo, GAS5 reduced tissue ROS levels, maintained vascular barrier function to reduce leakage, and ultimately attenuated sepsis-induced lung injury. Luciferase reporter assays revealed that GAS5 protected MITF from degradation by sponging miR-23, thereby forming a positive feedback loop consisting of MITF, GAS5, and miR-23. Despite the fact that the OS-activated MITF–GAS5–miR-23 loop boosted MITF-mediated p62 transcription, ECs do not need to increase mitophagy to exert mitochondrial quality control since MITF-mediated Nrf2 transcription exists. Compared to mitophagy, MITF-transcribed p62 prefers to facilitate the autophagic degradation of Keap1 through a direct interaction, thereby relieving the inhibition of Nrf2 by Keap1, indicating that MITF can upregulate Nrf2 at both the transcriptional and posttranscriptional levels. Following this, ChIP-PCR demonstrated that Nrf2 can also transcribe MITF, revealing that there is a reciprocal positive regulatory association between MITF and Nrf2. Conclusion: In sepsis, the ROS-activated MITF–GAS5–miR-23 loop integrated the antioxidant and autophagy systems through MITF-mediated transcription of Nrf2 and p62, which dynamically regulate the level and type of autophagy, as well as exert antioxidant and anti-inflammatory effects.

In this study, the effects of hot-rolled processes at different temperatures (420 °C, 450 °C, and 480 °C) and subsequent solid solution and aging treatments on the microstructure, mechanical properties, and corrosion properties of Al-Mg-Li alloys with trace Sc and Zr addition were investigated. The aging treatment of rolled sheets after solid solution treatment could obtain Al3Li particles and Al3(Sc, Zr)/Al3Li core–shell particles to improve the mechanical properties of Al-Mg-Li alloy products effectively. The results showed that, as the rolling temperatures increased from 420 °C to 480 °C, the alloy’s ultimate tensile strengths and yield strengths increased, while the corrosion resistance decreased. The increase in rolling temperature increased the precipitation-free zone (PFZ) width of the alloy, which undermined the corrosion resistance of the alloy. Moreover, elevating the hot rolling temperature changes the texture strength of the alloy. Particularly in the 480 °C hot-rolled sample, the decrease in the Brass texture strength and the increase in the S texture and Copper texture strength led to an increase in the Taylor factor (M). The increase in rolling temperature also raised the number density of the Al3(Sc, Zr)/Al3Li core–shell particles. The presence of such particles not only inhibits grain growth but also changes the strength mechanism from dislocation cutting to Orowan bypassing. Due to the combination effect of grain morphology, texture evolution, and precipitation behavior, the 480 °C hot-rolled sample had the highest properties.

The influence of various Ag contents on the microstructure, mechanical properties, and corrosion behavior of extruded Al-4.0Cu-1.1Li-0.4Mg-xAg-0.2Mn-0.2Zr (x = 0.4 and 0.9, wt.%) alloys was investigated. The alloy with 0.9 Ag content contains higher number density of slender T1 (Al2CuLi) precipitates along with some θ’ (Al2Cu) phases in the matrix than the alloy with 0.4 Ag content, which is associated with a more rapid hardening response and higher mechanical properties and corrosion resistance, particularly for aging at 130 °C. When aging at high temperatures (above 160 °C), the increase of Ag content mitigates hardness loss by preventing the T1 precipitates from coarsening, and makes the alloy decorate more coarse precipitates at grain boundaries, which leads to the fracture morphology mainly occupied by intergranular fracture. Furthermore, due to the simultaneous promotion of T1 precipitates at grain boundaries and in grain interiors, the 0.9 Ag-containing Al-Cu-Li-Mg-Ag alloy has almost no improvement in corrosion resistance.

Combined with microstructure characterization and properties tests, the effects of Zn contents on the mechanical properties, corrosion behaviors, and microstructural evolution of extruded Al–Li–Cu–Mg–Ag alloys were investigated. The results show that the increase in Zn contents can accelerate hardening kinetics and improve the hardness of peak-aged alloys. The Zn-added alloys present non-recrystallization characteristics combined with partially small recrystallized grains along the grain boundaries, while the T1 phase with finer dimension and higher number density could explain the constantly increasing tensile strength. In addition, increasing Zn contents led to a lower corrosion current density and a shallower maximum intergranular corrosion depth, thus improving the corrosion resistance of the alloys. Zn addition, distributed in the central layer of T1 phases, not only facilitates the precipitation of more T1 phases but also reduces the corrosion potential difference between the T1 phase and the matrix. Therefore, adding 0.57 wt.% Zn to the alloy has an excellent combination of tensile strength and corrosion resistance. The properties induced by Zn under the T8 temper (solid solution treatment + water quenching + 5% pre-strain+ isothermal aging), however, are not as apparent as the T6 temper (solid solution treatment + water quenching + isothermal aging).

Objective: The purpose of this meta-analysis was to evaluate the effects of Fufangkushen injection combined with chemotherapy in the treatment of stomach cancer. Materials and Methods: The relevant clinical trials about Fufangkushen injection combined with chemotherapy in the treatment of stomach cancer were search in the data bases of Pubmed, EMBASE, Cochran and CNKI. The data related to objective response rate, Karnofsky (KPS) score and toxicity were extracted and pooled using the Stata 11.0 software. Dichotomous data was presented as risk ratio (RR) and its 95% confidence interval (95% CI). Results: Thirteen relevant trials were included in this meta-analysis. Heterogeneity test indicated there was no statistical heterogeneity among the studies, thus the fixed effects mode was used to calculat the results. Pooled results indicated that the objective response rate (ORR) and KPS score improvement in Fufangkushen chemotherapy group was significant higher than that of control group (RR = 1.24, P < 0.05). Synthesis data also demonstrated the Fufangkushen injection can significantly decrease the risk of developing granulocytopenia in stomach cancer patients treated with chemotherapy (RR = 0.67,P < 0.05). Conclusion: Fufangkushen injection combined with chemotherapy can increase the objective response rate, improve the quality of life and decrease the risk of developing granulocytopenia in patients with stomach cancer. [ABSTRACT FROM AUTHOR]