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Iridium is the most promising material for ultra - high temperature structure parts oxidation - resistant coatings in aerospace field due to its high melting point, strong corrosion resistance and low oxygen permeability under high temperature. The main factors affecting the service life of the iridium coating were the microstructure and oxidation characteristics at high temperature. There were two ways to improve high temperature oxidation resistance of the coating: one was improving preparation process to enhance density of iridium coating so as to reduce coating failure caused by grain boundary diffusion, the other was preparing ceramic coating or alloying to defend iridium coating from contacting with the oxidizing environments and extend its lifetime. Aiming at the problems in the applications of iridium coating, the research progress on modification of iridium coating was reviewed. The development direction of iridium coating modification technology was prospected.

Background: Pneumonia has a high incidence in traumatic brain injury (TBI) patients and lacks effective treatments. Early mobilization (EM) may be a potentially effective treatment. Aim: To explore the impact of EM on TBI‐related pneumonia in the neurosurgical intensive care unit (NICU). Study Design: This study was a historical control study. 100 TBI patients who received EM intervention were prospectively included as the experimental group (EM cohort), and 250 TBI patients were retrospectively included as the control group. The propensity score matching (PSM) method was employed to balance baseline and minimize potential bias. The relationship between EM and TBI‐related pneumonia was investigated by univariate and multivariate logistic regression, then further determined by subgroup analysis. The influence of other variables was excluded by interaction analyses. Finally, the effect of EM on the prognosis of TBI patients was analysed by comparing the Glasgow Coma Scale (GCS) and the hospital stay. Results: After screening, 86 patients were included in the EM cohort and 199 patients were included in the control cohort. There were obvious differences between the two cohorts at baseline, and these differences were eliminated after PSM, when the incidence of pneumonia was significantly lower in the EM cohort than in the control cohort (35.0% vs. 61.9%, p <.001). Multivariate logistic regression showed that EM was an independent risk factor for TBI‐related pneumonia and was significantly associated with a decreased incidence of pneumonia. This correlation was present in most subgroups and was not affected by other variables (p for interaction >.05). Patients in the EM cohort had shorter length of ICU stay (6 vs. 7 days, p =.017) and higher GCS at discharge (12 vs. 11, p =.010). Conclusion: EM is a safe and effective treatment for TBI patients in NICU, which can reduce the incidence of pneumonia, help to improve prognosis and shorten the length of ICU stay. Relevance to Clinical Practice: Although the utilization rate of EM is low in TBI patients for various reasons, EM is still an effective method to prevent complications. Our study confirms that a scientific and detailed EM strategy can effectively reduce the incidence of pneumonia while ensuring the safety of TBI patients, which is worthy of further research and clinical application. [ABSTRACT FROM AUTHOR]

Cusatuzumab is a high-affinity, anti-CD70 monoclonal antibody under investigation in acute myeloid leukemia (AML). This two-part, open-label, multicenter, phase I/II trial evaluated cusatuzumab plus azacitidine in patients with newly diagnosed AML ineligible for intensive chemotherapy. Patients received a single dose of cusatuzumab at one of four dose levels (1, 3, 10, or 20 mg/kg) 14 days before starting combination therapy. In phase I dose escalation, cusatuzumab was then administered on days 3 and 17, in combination with azacitidine (75 mg/m2) on days 1-7, every 28 days. The primary objective in phase I was to determine the recommended phase II dose (RP2D) of cusatuzumab plus azacitidine. The primary objective in phase II was efficacy at the RP2D (selected as 10 mg/kg). Thirty-eight patients were enrolled: 12 in phase I (three per dose level; four with European LeukemiaNet 2017 adverse risk) and 26 in phase II (21 with adverse risk). An objective response (≥partial remission) was achieved by 19/38 patients (including 8/26 in phase II); 14/38 achieved complete remission. Eleven patients (37.9%) achieved an objective response among the 29 patients in phase I and phase II treated at the RP2D. At a median follow-up of 10.9 months, median duration of first response was 4.5 months and median overall survival was 11.5 months. The most common treatment-emergent adverse events were infections (84.2%) and hematologic toxicities (78.9%). Seven patients (18.4%) reported infusion-related reactions, including two with grade 3 events. Thus, cusatuzumab/azacitidine appears generally well tolerated and shows preliminary efficacy in this setting. Investigation of cusatuzumab combined with current standard-of-care therapy, comprising venetoclax and azacitidine, is ongoing.

Refractory high entropy alloys NbMoTaWTi and NbMoTaWZr were prepared by vacuum arc melting.The microstructure and component distribution characteristics were analyzed, and the dynamic behavior during room temperature to 1500℃, as well as the isothermal oxidation behavior at 1200℃ were studied. Results reveal that NbMoTaWTi mainly consists of single body-centred cubic (BCC) phase, and NbMoTaWZr is composed of BCC and Zr-rich phases.These two alloys are both seriously oxidized above 700℃. Comparatively, NbMoTaWTi alloy is superior to NbMoTaWZr in antioxidation below 1300℃.For both two alloys, the oxygen diffusion inward mainly occurs during isothermal oxidation at 1200℃ and catastrophic oxidation takes place after 3 h. The Ti and Zr addition cannot cause selective oxidation. Although these two elements form a composite oxide layer with other refractory metal oxides, the density and the ability to prevent oxidation is not enough.

Cellular senescence is characterized by a decrease in protein synthesis, although the underlying processes are mostly unclear. Chemical modifications to transfer RNAs (tRNAs) frequently influence tRNA activity, which is crucial for translation. We describe how tRNA N7-methylguanosine (m7G46) methylation, catalyzed by METTL1-WDR4, regulates translation and influences senescence phenotypes. Mettl1/Wdr4 and m7G gradually diminish with senescence and aging. A decrease in METTL1 causes a reduction in tRNAs, especially those with the m7G modification, via the rapid tRNA degradation (RTD) pathway. The decreases cause ribosomes to stall at certain codons, impeding the translation of mRNA that is essential in pathways such as Wnt signaling and ribosome biogenesis. Furthermore, chronic ribosome stalling stimulates the ribotoxic and integrative stress responses, which induce senescence-associated secretory phenotype. Moreover, restoring eEF1A protein mitigates senescence phenotypes caused by METTL1 deficiency by reducing RTD. Our findings demonstrate that tRNA m7G modification is essential for preventing premature senescence and aging by enabling efficient mRNA translation. The heterodimer of METTL1-WDR4 is responsible for adding methylation group to the N7 atom of guanine (m7G) in tRNA molecules. Here the authors show how the tRNA m7G modification mediates tRNA stability to control proteostasis by maintaining efficient protein synthesis, which is important for preventing premature senescence and aging. [ABSTRACT FROM AUTHOR]

The high-entropy metallic glasses, as a new kind of alloyed materials, have attracted considerable attention due to its excellent mechanical, anti-corrosion and magnetic properties and so forth, which combines the advantages of high-entropy alloys and metallic glasses. Herein, a comprehensive understanding of the concepts and features of high-entropy metallic glasses was provided as well as its preparation methods, distinguished structure and performance characteristics. The recent developments in the corrosion resistance mechanism and anti-corrosion properties were summarized. A new paradigm of using machine learning to design high-entropy metallic glasses was prospected. It was also pointed out that the precondition to the extensive use of this sort of materials is to explore the corrosion failure mechanism under the working conditions, and to achieve the micro-corrosion resistance mechanism perfection and its preparation process optimization. At present, the applied basic research on the development of high-entropy metallic glasses and its corrosion resistance will provide advanced technical support and material guarantee for the "Marching into the deep ocean" of China’s marine industry.

The refractory high-entropy alloys (RHEAs) usually form a multi-principal elements alloy with equal atomic ratio or near equal atomic ratio via adding a variety of high melting point elements, showing simple phase composition and excellent high temperature properties, and processing a broad application prospect in the field of superalloy. Based on the performance characteristics and preparation process of RHEAs, and from the perspective of the current situation and challenges in fabrication and forming, the property tuning methods and its research progress of RHEAs were summarized, as well as the achieved breakthrough and the facing dilemma of the additive manufactured RHEAs. A prospection on the composition design and optimization, material preparation and processing, and additive manufactured forming of RHEAs was also proposed.The following suggestions are put forward for the key research trend of RHEAs in the future: tuning phase composition and phases interface to overcome the strength-ductility trade-off of RHEAs, designing alloys by combining the mature traditional strengthening and toughening theory with the properties of RHEAs, modifying the formability and properties of RHEAs by drawing support from the processing characteristics of additive manufacturing technology, and investigating the servicing performance and failure mechanism in high temperature or multi-field coupling condition of RHEAs.

BACKGROUND The hydrocarbon generation materials in thin sections of black source rocks (such as black mudstone, oil shale), from the Chang 7 Member of the Upper Triassic Yanchang Formation in the Ordos Basin, are often partially or entirely black under the transmitted-light viewing system of a polarized optical microscope, because they are covered by black organic matter (such as oil, asphaltene) or opaque. OBJECTIVES To put forward an effective method to observe the hydrocarbon generation materials in thin sections of black source rock. METHODS A method for observation of characteristics of hydrocarbon generation materials of black source rock was proposed, using the reflected-light viewing system of a polarized optical microscope on electron probe thin sections. RESULTS The method can overcome the problem that hydrocarbon generation materials in thin section were covered by black organic matter or were opaque. The size, shape, structure, distribution of hydrocarbon generation materials and composition can be entirely and clearly observed in thin sections of black source rock. CONCLUSIONS In the long-term test, it has been proved that the method for observation of characteristics of hydrocarbon generation material in thin sections of black source rock by the reflected-light viewing system of a polarized optical microscope is simple and effective, and can be easily used in the study of hydrocarbon generation of tight oil and shale oil.

Two new quinazoline alkaloids versicomides G–H (1 and 2), together with seven known compounds, were isolated from Aspergillus versicolor HYQZ-215 obtained from the sediment of Qarhan Salt Lake. Their structures were elucidated by NMR, HRESIMS, and quantum chemical ECD calculations data. The antimicrobial activities of these compounds were evaluated against seven agricultural pathogenic fungi and eight clinically drug-resistant bacteria. [ABSTRACT FROM AUTHOR]