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In this study, we propose Fe–Mn-Cr/Ni as an economical drill collar overlay material applied via metal-cored arc welding (MCAW). A series of Fe–Mn-Cr/Ni overlay alloys with different Ni contents were prepared by MCAW, and their microstructure, non-magnetic, and wear properties were systematically investigated. The results show that the addition of Ni element can effectively improve the austenitization of the Fe–Mn-Cr/Ni overlay alloy and inhibit the formation of ferromagnetic hexagonal martensite (ε) and body-centered ferrite (α), thus improving the non-magnetic properties of the Fe–Mn-Cr/Ni overlay. With the increase of Ni addition from 0.6 to 4.7 wt.%, the average grain size gradually increases from 21.69 to 49.97 µm, and the overlay microstructure gradually evolves from columnar-like ε-martensite to wide ε-martensite band and eventually almost austenite. This change in microstructure as Ni content increases contributes to the reduction of relative permeability from 2.225 to 1.057 due to the increased austenite contents, at the cost of increased wear rate from 2.61 × 10−5to 4.55 × 10−5mm3·N−1·m−1due to the decay of wear-resistant ε-martensite skeleton. By controlling the Ni content, this work demonstrates the potential of preparing Fe-based austenitic wear-resistant layers with high Mn content and broadens the scope of austenitic non-magnetic deposited alloys for surface overlay strengthening or repairing of Fe-based non-magnetic drilling tools.

Estimating forest plant area index (PAI) with the simultaneous separation of overstory vegetation (OV) and understory vegetation (UV) is essential to study forest carbon and water cycles. Measuring PAI of OV and UV using conventional field surveys within forests is challenging, particularly for subtropical regions of China, where terrain slope can exceed 10°. The effective PAI (PAIe) instead of PAI for UV is usually measured by the conventional method of subtracting PAIe of OV from total PAIe. We find PAIe obtained using this strategy is underestimated by 25%–85%. Thus, we propose an approach to estimate PAIe and PAI of both OV and UV on sloped terrain by using single-station (SS) terrestrial laser scanner (TLS) data. Results are verified by comparing them with multistation (MS) TLS data acquired coincidentally. Then we analyze the effects of horizontal range and slope correction on PAI estimated from SS TLS data. The results show that the correlation between SS and MS PAI (PAIe) is strong, with $R^{2}$ of 0.88 (0.81) and 0.52 (0.75) ( ${p}~\lt 0.01$ ) for OV and UV, respectively. We recommend imposing a horizontal 20-m radius range for data acquired from SS TLS for PAI estimations. The difference between PAI estimations with and without a slope correction can be neglected. These results demonstrate that SS TLS data can serve as a means for PAI estimations of both OV and UV, which should help facilitate large-scale estimation in the subtropical forests of China.

Aim: This study aimed to estimate the chronic disease-free life expectancy (CDFLE) for distinct joint phenotypes of physical activity and obesity defined by six indicators in resource-limited areas. Subject and methods: In this study, a total of 38,789 participants aged 18 to 79 were recruited from the Henan rural cohort study. Logistic regression analysis was applied to assess the independent and combined effects of obesity and physical activity on chronic disease. The CDFLE according to obesity indicators and physical activity was measured via the Sullivan method. Results: Compared to participants who were physically active and nonobese defined by BMI, the multivariable-adjusted OR (95% CI) of the risk for prevalent chronic disease was 2.024 (1.833, 2.236) among those with obesity and physical inactivity, and the corresponding estimate for obese but physically active participants was 1.684 (1.550, 1.829). Compared with nonobese and physically active individuals, those with physical inactivity plus obesity classified by BMI, waist circumference, waist-to-hip ratio, waist-to-height ratio, body fat percent, and visceral fat index lost 4.42 (2.73, 6.12), 4.10 (2.95, 5.25), 4.84 (3.69, 5.98), 4.59 (3.47, 5.70), 3.86 (2.59, 5.13), and 3.81 (2.63, 4.99) years of CDFLE at age 50, respectively. The corresponding estimates for those who were obese but physically active were 2.75 (0.78, 4.72), 2.64, (1.43, 3.85), 3.14 (1.99, 4.30), 3.23 (2.09, 4.38), 2.22 (0.96, 3.48), and 1.85 (0.66, 3.03) years. Conclusion: Healthy body weight and physical activity were beneficial for chronic disease and CDFLE, and physical activity attenuated the negative effects of obesity.

Metallic-phase MoS2exhibits Pt-comparable electrocatalytic hydrogen evolution reaction (HER) performance in acidic conditions. However, the controllable synthesis of metallic-phase MoS2is quite challenging because the key factor determining the phase types of MoS2during synthesis is still unclear. Herein, the effect of organic sulfur sources on the formed MoS2phase is studied by use of thioacetamide (TAA), l-cysteine, and thiourea as sulfur sources. The TAA and l-cysteine produce metallic MoS2, while thiourea gives rise to semiconducting MoS2. Owing to the metallic phase and smaller size, the MoS2prepared with TAA and l-cysteine has a higher electrocatalytic HER activity than the MoS2obtained from thiourea. The HER overpotential of MoS2synthesized with TAA is only 210 mV for reaching the current density of 10 mA/cm2, and the corresponding Tafel slope is 44 mV/decade. Further studies find that the decomposition temperature of sulfur precursors is the key factor for the formation of metallic MoS2. Sulfur precursors with a lower decomposition temperature release sulfur ions quickly, which in turn stabilize the metallic phase and inhibit the growth of MoS2into large sizes. Our findings unveil the key factor for controlling the phase type of MoS2synthesized from organic sulfur precursors and will be very helpful for the synthesis of MoS2with high electrocatalytic activity.

The sluggish four-electron processes of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) limit the development of rechargeable Zn–air batteries (RZABs). Highly efficient ORR/OER bifunctional electrocatalysts are therefore highly desired for the commercialization of RZABs in large scale. Herein, the Fe–N4–C (ORR active sites) and NiFe-LDH clusters (OER active sites) are successfully integrated within a NiFe-LDH/Fe,N-CB electrocatalyst. The NiFe-LDH/Fe,N-CB electrocatalyst is first prepared by the introduction of Fe–N4into carbon black (CB), followed by the growth of NiFe-LDH clusters. The cluster nature of NiFe-LDH effectively avoids the blocking of Fe–N4–C ORR active centers and affords excellent OER activity. The NiFe-LDH/Fe,N-CB electrocatalyst thus exhibits an excellent bifunctional ORR and OER performance, with a potential gap of only 0.71 V. The NiFe-LDH/Fe,N-CB-based RZAB exhibits an open-circuit voltage of 1.565 V and a specific capacity of 731 mAh gZn–1, which is much better than the RZAB composed of Pt/C and IrO2. Particularly, the NiFe-LDH/Fe,N-CB-based RZAB displays excellent long-term charging/discharging cyclic stability and rechargeability. Even at a large charging/discharging current density (20 mA cm–2), the charging/discharging voltage gap is only ∼1.33 V and exhibits an increase smaller than 5% after 140 cycles. This work provides a new low-cost bifunctional ORR/OER electrocatalyst with high activity and superior long-term stability and will be helpful to the commercialization of RZAB in large scale.

• A near-α TNW700 titanium alloy exhibtis excellent superplaticity with elongation above 400% at 925°C. • Flow stress curve behave as long period strain hardening and large strain softening. • Continuous dynamic recrystallization induced primary α phase refinement at the later deformation stage. • The strain hardening is attributed to β grain growth, silicide precipitates and α phase solid solution strengthening. • Dynamic dislocation recovery, α grain refinement and β phase volume fraction increase together cause flow softening. The new near-α TNW700 titanium alloy is a potential candidate material for high performance ultrasonic/hypersonic aircrafts, which is designed for short-term service at 700°C. This study systematically investigated the superplastic deformation microstructure evolution and mechanism of TNW700 alloy at different strain rates and true strains at 925°C. Results show that TNW700 alloy exhibits excellent superplastic behavior in a constant strain rate range of 0.0005–0.005 s−1 with elongation above 400%. The peak stress decreases with decreasing strain rate, which is related to the increase of β-phase volume fraction caused by the increase of thermal exposure time. In addition, significant strain hardening is observed in early-middle stage of superplastic deformation, and flow softening is followed in middle-late stage. To rationalize these complex flow behaviors, electron backscatter diffraction (EBSD) and high resolution transmission electron microscopy (HRTEM) were used to characterize the microstructure. Strain hardening is correlated to the synergistic effect of β grain growth, dislocation accumulation, silicide precipitate, and solid solution strengthening of α phase. Continuous dynamic recrystallization (CDRX) induced the fragmentation of primary α grains in middle-late stage of superplastic deformation, and the refinement of α grains, the increase of β phase volume fraction and dynamic dislocation recovery are main causes of high strain softening. In addition, EBSD and TEM observations confirmed texture randomization, fine equiaxed primary α grains and intragranular dislocation movement, indicating that grain boundary sliding (GBS) accommodated by dislocation sliding / climb is the dominant superplastic deformation mechanism of TNW700 alloy. [ABSTRACT FROM AUTHOR]

The optimization of electromagnetic microwave absorbing (EMA) materials for radar stealth has been a continuous endeavor. However, meeting the defense requirements across multiple-frequency bands in increasingly complex and variable environments remains challenging. Drawing inspiration from the cytoskeleton-organelle structure, we designed and prepared a hierarchical MXene/NiFe2O4/calcined melamine foam (MNC) composite. The composite exhibits efficient and adjustable microwave absorption, infrared stealth, and solar absorption performance through the synergistic interaction of the components and the spatial effect of its novel microstructure. The composite achieves a minimum reflection loss of −58.57 dB and an effective absorption bandwidth (EAB) of 7.00 GHz, both of which can vary with the thickness. MNC also offers stable infrared stealth performance for heat sources ranging from 37 to 300 °C and high solar absorptivity up to 96.2%, promoting ambient-temperature-adaptive infrared stealth through electricity–sunlight cooperative regulation. With exceptional environmental adaptability characteristics such as photothermal conversion, lightness, elasticity, and hydrophobicity, the MNC composite holds promise as a multispectrum defense material for radar, infrared, and visible light for various forms of equipment, clothing, and wearables in harsh conditions.

High-entropy oxides are a new type of material with significant application potential. However, the lack of a universal HEO preparation method severely limits the property study and application of HEOs. Herein, we report a universal approach of spray pyrolysis for the preparation of various HEOs and study the electrocatalytic performance of HEOs toward the oxygen evolution reaction. FeCoNiMoWOxHEO exhibits an overpotential of 281 mV at 10 mA cm–2and a Tafel slope of 34.5 mV dec–1, which are far superior to those of the corresponding medium-entropy oxide and low-entropy oxide. It is found that the high entropy of the HEO greatly strengthens the interaction between Fe and Mo/W and produces abundant oxygen vacancies (OVs) around Mo and W. This work not only provides a universal preparation method for HEOs but also deepens our understanding of OER catalytic activity of HEOs.

The systemic fungal endophyte of the grass Achnatherum inebrians, Epichloë gansuensis,has important roles in enhancing resistance to biotic and abiotic stresses. In this work, we first evaluated the effects of E. gansuensison nitrogen metabolism, nitrogen use efficiency, and stoichiometry of A. inebriansunder varying nitrogen concentrations. The results demonstrated that E. gansuensissignificantly improved the growth of A. inebriansunder low nitrogen conditions. The fresh and dry weights, nitrogen reductase, nitrite reductase, and glutamine synthetase activity, NO3–, NH4+, N, and P content, and also the total N accumulation, N utilization efficiency, and N uptake efficiency were all higher in leaves of A. inebrianswith E. ganusensis(E+) plants than A. inebriansplants without this endophyte (E−) under low nitrogen availability. In conclusion, E. gansuensishas positive effects on improving the growth of A. inebriansunder low-nitrogen conditions by modulating the enzymes of nitrogen metabolism and enhancing nitrogen use efficiency.

Objective: NTRK mutations and clinicopathological factors in patients with lung cancer in northeast China were analyzed by next-generation sequencing (NGS), and references were provided for patients with NTRK mutations undergoing targeted therapy in northeast China.Methods: A total of 224 specimens in 173 patients with lung cancer were collected. This included 51 patients with matched tissue and whole blood samples,133 tissue samples, 84 whole blood samples, and 7 pleural effusion samples. NGS (520 genes) was used to detected NTRK mutations and clinicopathologic factors.Results: NTRK mutation was detected in eight patients (8/173, 4.6%), including four NTRK missense mutations (4/173, 2.3%), two NTRK fusion gene mutations (2/173, 1.2%), and two NTRK copy number deletions (2/173, 1.2%). Among the eight patients with NTRK mutations, four were associated with lung cancer driver gene mutations (3/4 EGFR, 1/4ALK); NTRK in two patients was inconsistent in tissue and paired whole blood testing; NTRK missense mutation was detected in one patient, and NTRK copy number deletion was detected in the other; and NTRK wild type was detected in two patients. There was no correlation between NTRK mutation and clinicopathologic factors (including gender, age, pathological type, smoking status, metastasis site).Conclusion: NTRK mutation was only 4.6%, effective fusion gene mutation was 1.2%, and common driver gene mutation in lung cancer was evident in 50% of patients. The results of NTRK were inconsistent with matched tissues and whole blood. Therefore, patients with NTRK mutation should use a variety of specimen types and large target area sequencing (panel) analysis method to provide individualized treatment.

Nucleic acid precipitation is important for virtually all molecular biology investigations. However, despite its crucial role, a systematic study of the influence factors of nucleic acid precipitation has not been reported. In the present work, via rational experimental design, key factors of nucleic acid precipitation, including the type of nucleic acid, temperature and time of incubation, speed and time of centrifugation, volume ratio of ethanol/isopropanol to nucleic acid solution, type of cation-containing salt solution and type of coprecipitator, were comprehensively evaluated in an attempt to maximize the efficiency of nucleic acid precipitation. Our results indicate that the optimal conditions of each influence factor of nucleic acid precipitation may vary in accordance with the chemistry, structure and length of nucleic acids.

Background

Background:The advent of chimeric antigen receptor (CAR) T-cell therapy has changed the treatment landscape for refractory/relapsed B-cell lymphoma (r/r B-NHL). However, there are limited data on outcomes in older patients (age≥65 years) treated with CAR -T-cell therapy, particularly in patients older than 70 years.

Estimating heavy metals (HMs) distribution with high precision is the key to effectively preventing Chinese medicinal plants from being polluted by the native soil. A total of 44 surface soil samples were gathered to detect the concentrations of eight HMs (As, Hg, Cu, Cr, Ni, Zn, Pb and Cd) in the herbal growing area of Luanping County, northeastern Hebei Province, China. An absolute principal component score/multiple linear regression (APCS/MLR) model was used to quantify pollution source contributions to soil HMs. Furthermore, the source contribution of each sampling point and environmental data were simultaneously incorporated into a stepwise linear regression model to identify the crucial indicators for predicting soil HMs spatial distributions. The results showed that 88% of Cu, 72% of Cr and 72% of Ni came from natural sources; 50% of Zn, 49% of Pb and 59% of Cd were mainly caused by agricultural activities; and 44% of As and 56% of Hg originated from industrial inputs. When three source contribution rates and environmental data were simultaneously incorporated in a stepwise linear regression model, the fitting accuracy was significantly improved, and the model could explain 31–86% variance of soil HMs concentration. This study introduced three source contributions of each sampling point based on APCS/MLR analysis as new covariates to improve soil HMs estimation precision, thus providing a new approach for predicting the spatial distribution of HMs using small sample sizes at the county scale.

Alkaptonuria (AKU) is an autosomal recessive disorder of tyrosine metabolism, which is caused by a defect in the enzyme homogentisate 1,2-dioxygenase (HGD) with subsequent accumulation of homogentisic acid. Presently, more than 100 HGDmutations have been identified as the cause of the inborn error of metabolism across different populations worldwide. However, the HGDmutation is very rarely reported in Asia, especially China. In this study, we present mutational analyses of HGDgene in one Chinese Han child with AKU, which had been identified by gas chromatography-mass spectrometry detection of organic acids in urine samples. PCR and DNA sequencing of the entire coding region as well as exon-intron boundaries of HGDhave been performed. Two novel mutations were identified in the HGDgene in this AKU case, a frameshift mutation of c.115delG in exon 3 and the splicing mutation of IVS5+3 A>C, a donor splice site of the exon 5 and exon-intron junction. The identification of these mutations in this study further expands the spectrum of known HGDgene mutations and contributes to prenatal molecular diagnosis of AKU.

Abstract: A new analytical method for springback of small curvature plane bending is addressed with unloading rule of classical elastic-plastic theory and principle of strain superposition. We start from strain analysis of plane bending which has initial curvature, and the theoretic derivation is on the widely applicable basic hypotheses. The results are unified to geometry constraint equations and springback equation of plane bending, which can be evolved to straight beam plane bending and pure bending. The expanding and setting round process is one of the situations of plane bending, which is a bend-stretching process of plane curved beam. In the present study, springback equation of plane bending is used to analyze the expanding and setting round process, and the results agree with the experimental data. With a reasonable prediction accuracy, this new analytical method for springback of plane bending can meet the needs of applications in engineering.

Flowerlike supramolecular architectures were fabricated from fulleropyrrolidines bearing a small para-, meta-, or ortho-nitrophenyl group. The self-assembled architectures were characterized by scanning electron microscopy(SEM) and X-ray diffraction(XRD). It was found that these flowerlike architectures were assembled from nanoplates that formed from fundamental subunit of interdigitated lamellar bilayer structure.