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Cold-rolled metastable β-type Ti–38Nb-0.2O alloy was subjected to annealing treatment to obtain different precipitates and grain sizes. The influence of annealing on microstructure and mechanical properties was investigated. The alloy annealed at 673 ​K or 773 ​K exhibited a single-stage yielding with high strength and low uniform elongation, due to the residual work hardening and the precipitation of ω or α phases. The alloy annealed at above 873 ​K exhibited an obvious double yielding behavior resulting from the stress-induced martensitic transformation. The grain growth kinetics of single β phase alloy is sensitive to temperature, and it is suggested that the existence of oxygen decreases the grain growth exponent and increases the required activation energy for grain growth. The critical stress for slip decreased monotonously with the increase of grain size, following the classic Hall-Petch relationship. However, the critical stress for martensitic transformation decreased to a minimum and then increased again, as the grain size increased. The results are worth for design of the heat-treatment parameters of the Ti–38Nb-0.2O alloy for engineering applications.

The coronavirus disease 2019 (COVID-19) pandemic has become a public health emergency of global concern. In China, traditional Chinese medicine has been widely administered to COVID-19 patients without sufficient evidence. To evaluate the efficacy of Shenhuang Granule (SHG) for treating critically ill patients with COVID-19, we included in this study 118 patients who were admitted to the ICU of Tongji Hospital between January 28, 2020 and March 28, 2020. Among these patients, 33 (27.9%) received standard care plus SHG (treatment group) and 85 (72.1%) received standard care alone (control group). Enrolled patients had a median (IQR) age of 68 (57-75) years, and most (79 [67.1%]) were men. At end point of this study, 83 (70.3%) had died in ICU, 29 (24.5%) had been discharged from ICU, and 6 patients (5.2%) were still in ICU. Compared with control group, mortality was significantly lower in treatment group (45.4% vs. 80%, p < .001). Patients in treatment group were less likely to develop acute respiratory distress syndrome (ARDS) (12 [36.3%] vs. 54 [63.5%], p = 0.012) and cardiac injury (5 [15.1%] vs. 32 [37.6%], p = 0.026), and less likely to receive mechanical ventilation (22 [66.7%] vs. 72 [84.7%], p = 0.028) than those in control group. The median time from ICU admission to discharge was shorter in treatment group (32 [20-73] days vs. 76 [63-79] days, p = 0.0074). These findings suggest that SHG treatment as a complementary therapy might be effective for critically ill adults with COVID-19 and warrant further clinical trials.

A Ti–8Nb–2Fe-0.2O (wt.%) alloy with high strength, high elastic admissible strain (δ) and low cost was designed using d-electron theory combined with electron-to-atom ratio (e/a‾) approach. Interstitial oxygen was introduced to strengthen the matrix of the alloy. The β-solution treated alloy was mainly composed of α″ martensite with internal {111}α″ type I nano-twins. The α″ martensite with hexagonal-like crystal structure caused by interstitial oxygen showed a high strength of 1.1 GPa but limited ductility. The alloy generated equiaxed fine-grained α phase embedded by β matrix via hot rolling and subsequent annealing in α + β phase field. The obtained alloy indicated a good combination of mechanical properties with ultimate tensile strength, Young’s modulus, ductility and δ value of 1029 MPa, 74 GPa, 21% tensile elongation and 1.32%, respectively. These findings demonstrate that interstitial oxygen and martensitic nano-twins can be used to strengthen the soft α″ martensite and high elastic admissible strain can be obtained by formation of equiaxed fine-grained α phase embedded by β matrix in this Ti–8Nb–2Fe-0.2O alloy for orthopedic implant. Keywords: Titanium alloy, Oxygen, Microstructure, Strength, Elastic admissible strain

Background: Ever since the COVID-19 pneumonia emerged in Wuhan, China, in December 2019, it has rapidly spread worldwide, resulting in high mortality. This study aimed to delineate the clinical characteristics of critically ill patients with COVID-19 infection in the intensive care unit. Methods: In this retrospective study, the clinical characteristics of 88 critically ill patients with COVID-19 infection were collected. Analysis among three subgroups, classified according to the survival time, was performed. Results: The median age was 70.7(62.3-78.25) years of critical ill patients. Hypertension (43.2%) was the most frequent underlying disease. At the time of admission, compared to other patients, patients of the≤7 days category showed greater impairment of consciousness, as per the Glasgow Coma Scale (GCS) scores(11.0±2.9, P 14days (P=0.01). Conclusion: Critically ill patients with COVID-19 infection showed high risk of mortality. The primary immune response of lymphocytes against the COVID-19 infection was severely destroyed. Higher GCS score predicted greater possibility of survival. However, acute kidney injury may be an indicator of worse outcome.

We report spin–orbit torque (SOT) based on spin-torque ferromagnetic resonance (ST FMR) in a single ferrimagnetic layer. Temperature-dependent anomalous Hall resistance ([Formula: see text]) shows a magnetic compensation temperature ([Formula: see text]) of about 205 K. Temperature-dependent ST FMR is performed to quantify SOT; the torque is exerted to the total moment, and the SOT sign diverges as the temperautre approaches [Formula: see text]. X-ray photoelectron spectroscopy revealed that SOT arises due to the broken symmetry of the bulk spatial inversion along the normal direction of the film. Our finding provides useful information about the controlled temperature of bulk spin–orbit coupling in single layer GdFeCo.

Annealing at different temperatures was applied to a hot-rolled Ti-15Nb-5Zr-4Sn-1Fe (wt.%) alloy to obtain α + β dual-phase structure with varying α phase fraction. The evolutions of α + β dual-phase structure, mechanical properties, and deformation mechanisms were systematically investigated. With increasing α phase from 5.5% to 33.7%, the stability of the retained β matrix was gradually enhanced and the β domain size was decreased. The deformation mechanisms changed from stress-induced β to αʹ martensitic transformation to stress-induced β to αʺ martensitic transformation, mechanical twinning of the β matrix, and finally dislocation slip accompanied with increasing α phase. Accordingly, Young’s modulus decreased monotonously attributed to gradually suppressed athermal ω phase, while the yield strength first decreased slightly owing to the change of stress-induced martensite from αʹ to αʺ, and then increased rapidly when the long-range stress-induced martensite was suppressed. A good combination of low Young’s modulus, high strength, and high ductility was obtained in a microstructure composed of ultrafine grained α + β dual-phase showing dislocation dominated plastic deformation. This study possibly serves as a templet to guide the development of ultrafine grained α + β dual-phase structured metastable β-Ti alloy for biomedical application.

The bipolar resistance switching effect is observed in ZnO/BaTiO3/C structure. The resistance switching behavior can be modulated by white light. The resistance switch states and threshold voltage can be changed when subjected to white light. This research can help explore multi-functional materials and applications in nonvolatile memory device.

The effects of solution temperature and Cu content on the properties and microstructure of Sm (CobalFe0.21CuxZr0.03)7.6 (x = 0.06, 0.08, 0.10) permanent magnets were investigated systematically. The results showed that TbCu7 single-phase was obtained after solution treatment at optimum temperature. The best magnetic properties of Br = 1.010 T and (BH)max = 190.2 kJ/m3 were obtained for Sm (CobalFe0.21Cu0.08Zr0.03)7.6 by a proper solution treatment at 1478 K. At a lower solution temperature, the Co-rich FeCoZr phase was monitored, and a “step” was observed in the demagnetization curves of aged samples. At a higher solution temperature, composition segregation of the matrix gradually occurs, and a Zr-rich SmCoZr phase was found. However, at a slightly higher solution temperature with superabundant Cu, the precipitated phase remained FeCoZr phase, resulting in a worse remanence. All the above changes were related to the cellular structures.

The influences of cryogenic treatments, i.e. liquid nitrogen quenching (LNQ) and water quenching followed with liquid nitrogen immersion (WQ-L) on phase transformations, microstructural development and mechanical properties during aging treatment have been studied in near βTi-5Al-3Mo-3V-2Cr-2Zr-1Nb-1Fe alloy. The results showed that cryogenic treatments produced more O′ and ω-embryos in comparison with water quenching (WQ). After aging treatment, the LNQ sample and WQ-L sample formed finer and higher number density of α precipitates within β grains, which is attributed to the increase of O′ domains provides more potent nucleation sites for α. Tensile tests indicated that the cryogenic treatments improved tensile strength without trading-off ductility obviously. The ultimate tensile strength of aged LNQ and WQ-L sample was increased by 142 MPa and 62 MPa, respectively.

Background Coronavirus disease 2019 (COVID-19) is still a pandemic, with a high mortality rate in severe/critical cases. Therapies based on the Shenghuang Granule have proved helpful in viral infection and septic shock. Hypothesis/Purpose The objective of the current study was to compare the efficacy and safety of the traditional Chinese medicine, Shenhuang Granule, with standard care in hospitalized patients with severe/critical COVID-19. Study Design and Methods This was an open-label, multicenter, randomized, controlled clinical trial. At 4 medical centers, a total of 111 severe/critical patients were randomly assigned to receive Shenhuang Granule (SHG group) twice a day for 14 days, in addition to standard care, or to receive standard care alone (Control group). The maximal follow up time was 75 days. The clinical endpoint was clinical improvement and mortality. Results 54 patients were assigned to the control group and 57 to the SHG group. The overall mortality was 75.9% (41/54) in the control group, and 38.6% (22/57) in the SHG group (p, Graphical abstract Image, graphical abstract

The antiplatelet and antithrombotic effects of ent-16β,17-dihydroxy-kauran-19-oic acid (DDKA) isolated from Siegesbeckia pubescens were investigated with different methods both in vitro and in vivo. We tested the antithrombotic activity of DDKA in arterio-venous shunt model. The effects of DDKA on adenosine diphosphate (ADP)-, Thrombin-, Arachidonic acid-induced rat platelets aggregation were tested in vitro. We also assessed its bleeding side effect by measuring coagulation parameters after intravenous administration for 5 days and investigated the potential mechanisms underlying such activities. In vivo, DDKA significantly reduced thrombus weight in the model of arterio-venous shunt. Meanwhile, DDKA increased plasma cAMP level determined by radioimmunoassay in the same model. Notably, DDKA prolonged PT and APTT in rats after intravenous administration DDKA for successive 5 days. In vitro, pretreatment with DDKA on washed rat platelets significantly inhibited various agonists stimulated platelet aggregation and caused an increase in cAMP level in platelets activated by ADP. These findings support our hypothesis that DDKA possesses antiplatelet and antithrombotic activities. The mechanisms underlying such activities may involve the anticoagulatory effect and cAMP induction.

The aim of this study was to evaluate the antitumor potential of Macrothelypteris torresiana by studying in vitro antitumor activity of the protoapigenone, as well as in vivo antitumor activity and acute/subacute oral toxicity of the total flavonoid fraction from the roots of M. torresiana. Considering that the protoapigenone is a main constituent of the total flavonoid fraction and it might play a key role in the antitumor activity of M. torresiana, the MTT assay was used to investigate the in vitro antitumor activity of the protoapigenone. Our study revealed that the protoapigenone of M. torresiana showed significant antitumor activity towards Hep G2, Tca-8113, MCF-7, M5 and K562 with IC(50) values of 2.3, 0.6, 0.8, 0.3 and 0.9 μg/ml, respectively. The antitumor potential of the total flavonoid fraction was evaluated using preparations 1, 2 and 3, which were prepared by total flavonoid fraction directly diluted with sterile saline, dissolved using sodium carboxymethyl cellulose (CMC-Na) and included by hydroxypropyl-β-cyclodextrin, respectively. These were investigated in vivo using mouse sarcoma S-180 in BALB/c mice after completing tumor inoculation for 24h. Pronounced antitumor activity was observed in the treated groups for preparations 2 and 3, and the high and medium doses in particular showed very high inhibition ratio of tumor growth (>50%). No significant difference was observed when compared to the positive control group (5-fluorouracil). The acute/subacute oral toxicity test was performed, and the results of acute oral toxicity showed that the LD(50) values of preparations 2 and 3 were 2.76 and 0.87 g/kg body wt., respectively. According to the results of the subacute oral toxicity study, the total flavonoid fraction had low toxicity. The overall results of this study suggest that the total flavonoid fraction from the roots of M. torresiana shows significant antitumor activity and represents a potential source of medicine for the treatment of cancer.

A hysteresis loop of current-voltage (I–V) characteristics based on ZnO/C hybrid structures is observed at room temperature. The I–V hysteresis loop in ZnO/C hybrid structure can be modified by white light. Negative photoconductivity phenomenon is observed in ZnO/C hybrid structure by adding to extra illumination and the area within the I–V hysteresis loop decreases also. These phenomenon should be due to the space charges storage and surface effect in the sample. This work gives a help for exploring the optical-controlled memory device.

An obvious unipolar resistance switching is observed in BaTiO3/ZnO/BaTiO3/Carbon films. The resistance switching effect and the set voltage can be modulated by light irradiation. The RS ratio increases with light intensity. These phenomena are explained using trap/detrap mechanism.