To develop an aluminum alloy that combines excellent mechanical properties with good castability for near-net-shape casting of automotive structural parts, new Cu–free medium Mg 7xxx aluminum alloys ...with minor Zr (0.1%) and Ti (0, 0.1, and 0.2%) (all contents in wt% unless stated otherwise) elemental content were investigated as potential candidates. The effects of a vulnerable temperature interval and grain refinement on the hot tearing susceptibility (HTS) were investigated in this work to prevent hot tearing. Al–6Zn–(1.3–1.5)Mg–0.1Zr–(0.1–0.2)Ti alloys show 140–150% of ultimate tensile strength (370–390 MPa), 150–180% of elongation (10–12%), 60–80% of medium-thick-wall fluidity, and equivalent thin-wall fluidity, compared to the respective properties of the commercial A356 alloy. Medium-thick-wall fluidity depended on the heat release upon solidification of the alloy investigated, and thin-wall fluidity depended on the surface energy of the alloy in molten state. When the Ti content was increased, a concave variation in the medium-thick-wall fluidity and a monotonic increase in the thin-wall fluidity were observed. In terms of hot tearing, Ti addition led to a decrease in the HTS, which eventually reached zero. By adding 3% Si, hot tearing could be prevented; however, at the same time, elongation was found to decrease to less than 4%. The grain size reduction and morphology alteration due to the combined addition of 0.2% Ti and 0.1% Zr led to an improvement in castability because of a delay in crystal coherency, decrease in solidification time and vulnerable time period, and suppression of Fe-containing intermetallic and T phase crystallization.
•New Cu–free medium Mg 7xxx aluminum alloys with minor Ti and Zr are investigated.•These alloys show an excellent combination of strength, ductility, and castability.•With increasing Ti content up to 0.2%, the HTS decreases, eventually reaching zero.•The addition of 0.2% Ti–0.1% Zr improves alloy fluidity and prevents hot tearing.•The mechanisms of fluidity and HTS dependence on Mg, Si and Ti contents are proposed.
Simple physical blending of SiO2 and ethyl‐capped Ge gels leads to flexible dimensional control of Ge nanoparticles, and an increasing weight fraction of the latter leads to ordered 3D porous ...nanoparticle assemblies (see figure). The long‐range ordering of the 3D porous Ge nanoparticles and their very thin pore wall thicknesses (<20 nm) induce excellent cycling performance, showing only a 2% capacity decrease after 100 cycles.
Ultralong germanium nanotubes (Ge NTs; see picture) are synthesized in high yield from core–shell Ge–Sb nanowires by utilizing the Kirkendall effect at 700 °C. The Ge NTs have an exceptionally high ...rate capability (40 Ag−1) while maintaining a reversible capacity of more than 1000 mAhg−1 over 400 cycles, with minimal capacity fading when paired with a LiCoO2 cathode in a lithium‐ion cell.
Background:Outcomes of cryoballoon ablation for persistent atrial fibrillation (AF) are unclear, especially in Japanese patients, so the effectiveness and safety of cryoballoon ablation in clinical ...practice were retrospectively compared with those of contact force-sensing radiofrequency (CFRF) ablation including the high-power protocol.Methods and Results:Consecutive patients with persistent AF were reviewed, and 253 and 265 patients who underwent cryoballoon and CFRF ablation, respectively, were enrolled. The primary endpoint was atrial arrhythmia recurrence. The secondary endpoints were periprocedural complications and repeat ablation. The rate of additional left atrial (LA) ablation after pulmonary vein isolation (PVI) was similar between groups (68.8% cryoballoon vs. 74.0% CFRF, P=0.19). Freedom from atrial arrhythmia recurrence was comparable between groups over a follow-up of 25.5±12.5 months (72.3% cryoballoon vs. 69.8% CFRF; adjusted hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.59–1.21, P=0.36). Outcomes were similar in the subgroups of PVI alone and PVI plus additional LA ablation. LA posterior wall isolation, absence of defragmentation, and low creatine clearance, but not catheter selection, were associated with the primary endpoint. Periprocedural complications (adjusted HR 0.73, 95% CI 0.34–1.54, P=0.41) and repeat ablation (adjusted HR 1.11, 95% CI 0.71–1.74, P=0.64) were similar for both procedures.Conclusions:Cryoballoon ablation for persistent AF in Japanese clinical practice had acceptable outcomes comparable to those of advanced CFRF ablation.
Background:There is a paucity of data on the management and prognosis of cancer-associated venous thromboembolism (VTE), leading to uncertainty about optimal management strategies.Methods and ...Results:The COMMAND VTE Registry is a multicenter registry enrolling 3,027 consecutive acute symptomatic VTE patients in Japan between 2010 and 2014. We divided the entire cohort into 3 groups: active cancer (n=695, 23%), history of cancer (n=243, 8%), and no history of cancer (n=2089, 69%). The rate of anticoagulation discontinuation was higher in patients with active cancer (43.5%, 27.0%, and 27.0%, respectively, at 1 year, P<0.001). The cumulative 5-year incidences of recurrent VTE, major bleeding, and all-cause death were higher in patients with active cancer (recurrent VTE: 17.7%, 10.2%, and 8.6%, P<0.001; major bleeding: 26.6%, 8.8%, and 9.3%, P<0.001; all-cause death: 73.1%, 28.6%, 14.6%, P<0.001). Among the 4 groups classified according to active cancer status, the cumulative 1-year incidence of recurrent VTE was higher in the metastasis group (terminal stage group: 6.4%, metastasis group: 22.1%, under chemotherapy group: 10.8%, and other group: 5.8%, P<0.001).Conclusions:In a current real-world VTE registry, patients with active cancer had higher risk for VTE recurrence, bleeding, and death, with variations according to cancer status, than patients without active cancer. Anticoagulation therapy was frequently discontinued prematurely in patients with active cancer in discordance with current guideline recommendations.
Dissolution of iron from mineral dust particles greatly depends upon the type and amount of copresent inorganic anions. In this study, we investigated the roles of sulfate, chloride, nitrate, and ...perchlorate on the dissolution of maghemite and lepidocrocite in ice under both dark and UV irradiation and compared the results with those of their aqueous counterparts. After 96 h of reaction, the total dissolved iron in ice (pH 3 before freezing) was higher than that in the aqueous phase (pH 3) by 6–28 times and 10–20 times under dark and UV irradiation, respectively. Sulfuric acid was the most efficient in producing labile iron under dark condition, whereas hydrochloric acid induced the most dissolution of the total and ferrous iron in the presence of light. This ice-induced dissolution result was also confirmed with Arizona Test Dust (AZTD). In the freeze–thaw cycling test, the iron oxide samples containing chloride, nitrate, or perchlorate showed a similar extent of total dissolved iron after each cycling while the sulfate-containing sample rapidly lost its dissolution activity with repeating the cycle. This unique phenomenon observed in ice might be related to the freeze concentration of protons, iron oxides, and inorganic anions in the liquid-like ice grain boundary region. These results suggest that the ice-enhanced dissolution of iron oxides can be a potential source of bioavailable iron, and the acid anions critically influence this process.
This study demonstrates that the production of reactive oxidizing species (e.g., hydroxyl radical (•OH)) during the photolysis of nitrite (NO2 –) or nitrate (NO3 –) leads to the oxidative conversion ...of arsenite (As(III)) to arsenate (As(V)). While the direct UV photolytic oxidation of As(III) was absent, nitrite (20 or 200 μM) addition markedly accelerated the oxidation of As(III) under UV irradiation (λ > 295 nm), which implies a role of NO2 – as a photosensitizer for As(III) oxidation. Nitrate-mediated photooxidation of As(III) revealed an initial lag phase during which NO3 – is converted into NO2 –. UV-Photosensitized oxidation of As(III) was kinetically enhanced under acidic pH condition where nitrous acid (HNO2) with a high quantum yield for •OH production is a predominant form of nitrite. On the other hand, alkaline pH that favors the photoinduced transformation of NO3 – to NO2 – significantly facilitated the catalytic reduction/oxidation cycling, which enabled the complete oxidation of As(III) at the condition of As(III)/NO2 – ≫ 1 and markedly accelerated NO3 –-sensitized oxidation of As(III). The presence of O2 and N2O as electron scavengers enhanced the photochemical dissociation of NO2 – via intermolecular electron transfer, initiating the oxidative As(III) conversion route probably involving NO2• and superoxide radical anion (O2•–) as alternative oxidants. The outdoor experiment demonstrated the capability of NO2 – for the photosensitized production of oxidizing species and the subsequent oxidation of As(III) into As(V) under solar irradiation.
This study analyzed oral squamous cell carcinoma (OSCC) genomes and transcriptomes in relation to perineural invasion (PNI) and prognosis using Cancer Genome Atlas data and validated these results ...with GSE41613 data. Gene set enrichment analysis (GSEA), gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes were conducted. We identified 22 DNA mutations associated with both overall survival (OS) and PNI. Among them, TGFBR1 and RPS6KA4 mRNAs were overexpressed, while TYRO3 and GPR137 mRNAs were underexpressed in PNI patients. Among the 141 mRNA genes associated with both OS and PNI, we found overlap with PNI-related DNA mutations, including ZNF43, TEX10, TPSD1, and PSD3. In GSE41613 data, TGFBR1, RPS6KA4, TYRO3, GPR137, TEX10 and TPSD1 mRNAs were expressed differently according to the prognosis. The 22 DNA-mutated genes clustered into nervous system development, regulation of DNA-templated transcription, and transforming growth factor beta binding. GSEA analysis of mRNAs revealed upregulation of hallmarks epithelial mesenchymal transition (EMT), TNFα signaling via NF-κB, and IL2 STAT5 signaling. EMT upregulation aligned with the TGFBR1 DNA mutation, supporting its significance in PNI. These findings suggest a potential role of PNI genes in the prognosis of OSCC, providing insights for diagnosis and treatment of OSCC.
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