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• Laser repair samples with outstanding tensile properties have been obtained. • Well matching of microhardness between RZ and SZ has been achieved. • Synergistic deformation between RZ and SZ was realized during tensile process. • Mechanism of strain evolution of RZ and SZ was investigated. In the context of laser repairing damaged forging titanium (Ti) alloys, a common challenge is the significant reduction in elongation of the repaired samples compared to that of the substrate. In this work, directed energy deposition (DED) technology was employed to repair the TC4 (Ti-6Al-4V) forgings by manipulating the Al and V contents of the repaired zone (RZ). Subsequent evaluation encompassed the microstructure, microhardness, and tensile properties across the laser repair deposition samples (LRDs). The results revealed that despite the LRD TC4–0Ti's strength reaching 97.80% of the substrate, its elongation is only 43.93% of the substrate. Upon appropriately reducing the Al and V contents of RZ, the LRD TC4–5Ti demonstrates a strength of 935.04 MPa and an elongation of 14.59%, achieving 98.70% and 82.38% of the substrate, respectively. As the Al and V contents of RZ are further decreased, the strength of the LRDs gradually diminishes, falling below the forging standards. Utilizing digital image correlation (DIC) technology, the deformation behavior of different zones during the tensile process of these LDRs was investigated. The results indicated a concentration of strain distribution within either RZ or the substrate zone (SZ) of the LRDs during the tensile process, which signifies the mismatch of deformation capacity between these two zones. Consequently, the tensile properties of the LRDs were adversely affected. By judiciously adjusting the Al and V contents of RZ, the abovementioned mismatch phenomenon can be ameliorated, which facilitates a synergistic strain behavior between SZ and RZ during the tensile process, aiding in the homogenization of strain distribution and consequently enhancing the tensile properties of the LRDs. [Display omitted] [ABSTRACT FROM AUTHOR]

Planar fractional-winding transformers have the advantages of low winding losses with fractional turns and easy integration, which have shown great potential in improving efficiency and power density in recent years. The current fractional-winding transformers all adopt a completely symmetrical structure, which is too strict for the transformer structure and makes it difficult to use the space flexibly. In addition, it is unclear the impact of structural asymmetry on the operation of the converters. This article mainly focuses on the structural analysis of the fractional-winding transformer and proposes flexible asymmetric structures. The requirements for the structural design of fractional winding transformers are clarified. The results show that the structural constraints of the transformer can be greatly relaxed, and a flexible asymmetrical structure can also work. The influence of key structural parameters on the circuit is also analyzed. An LLC converter based on a 1/3-turn asymmetric structure transformer was built, which worked well and validated the analysis.

• Composition-controlled SLM ––Ti–6Al–4V alloy is assessed pre- and post-heat treatment. • Microstructure optimization achieves excellent strength-ductility balance. • LCF properties match forged counterparts, doubling fatigue life under high strain. • The role of microstructure in enhancing LCF properties of the alloy is discussed. Improving the low-cycle fatigue (LCF) properties of additively manufactured Ti–5.6Al–3.8V alloy is critical in ensuring its service safety and represents a significant research challenge. This work discusses a solution that optimizes the alloy's microstructure and ductility by precisely controlling the over-saturated strengthening elements and heat treatment. This was accomplished using selective laser melting (SLM), heat treatment at 800 °C for 2 h, and furnace cooling on a Ti–5.6Al–3.8V alloy with tightly controlled Al, V, and O concentrations in a lower range. The results showed that the SLM-fabricated Ti–5.6Al–3.8V alloy, post-heat treatment, exhibited α laths with a width of ∼1.4 μm and β columnar grains with a diameter of ∼126 μm, without experiencing coarsening or variant selection phenomena. The alloy balanced strength and ductility post-heat treatment with a UTS of 1015 MPa and an EL of 16.5% relative to the as-deposited state (UTS of 1199 MPa and EL of 11.9%). Notably, the LCF properties of the heat-treated SLM Ti–5.6Al–3.8V alloy are superior to those of other Ti–6Al–4V alloys produced by additive manufacturing and comparable to traditional forgings. At high strain amplitudes (1–1.5%), the fatigue life of this alloy was twice that of the Ti–6Al–4V forgings. Furthermore, we comprehensively analyzed the microstructure, strength, and ductility of the SLM Ti–5.6Al–3.8V alloy to elucidate the factors influencing its LCF properties. These findings provide a solid foundation for improving the LCF properties of additively manufactured Ti–6Al–4V alloy, thereby contributing to its safe and reliable use in critical applications. [ABSTRACT FROM AUTHOR]

Human endogenous retroviruses (HERVs) are remnants of retroviral infections in human germline cells from millions of years ago. Among these, ERVW-1 (also known as HERV-W-ENV, ERVWE1, or ENVW) encodes the envelope protein of the HERV-W family, which contributes to the pathophysiology of schizophrenia. Additionally, neuropathological studies have revealed cell death and disruption of iron homeostasis in the brains of individuals with schizophrenia. Here, our bioinformatics analysis showed that differentially expressed genes in the human prefrontal cortex RNA microarray dataset (GSE53987) were mainly related to ferroptosis and its associated pathways. Clinical data demonstrated significantly lower expression levels of ferroptosis-related genes, particularly Glutathione peroxidase 4 (GPX4) and solute carrier family 3 member 2 (SLC3A2), in schizophrenia patients compared to normal controls. Further in-depth analyses revealed a significant negative correlation between ERVW-1 expression and the levels of GPX4/SLC3A2 in schizophrenia. Studies indicated that ERVW-1 increased iron levels, malondialdehyde (MDA), and transferrin receptor protein 1 (TFR1) expression while decreasing glutathione (GSH) levels and triggering the loss of mitochondrial membrane potential, suggesting that ERVW-1 can induce ferroptosis. Ongoing research has shown that ERVW-1 reduced the expression of GPX4 and SLC3A2 by inhibiting their promoter activities. Moreover, Ferrostatin-1 (Fer-1), the ferroptosis inhibitor, reversed the iron accumulation and mitochondrial membrane potential loss, as well as restored the expressions of ferroptosis markers GSH, MDA, and TFR1 induced by ERVW-1. In conclusion, ERVW-1 could promote ferroptosis by downregulating the expression of GPX4 and SLC3A2, revealing a novel mechanism by which ERVW-1 contributes to neuronal cell death in schizophrenia.

Bistatic PRI agile radar has broad application prospects in modern electronic countermeasures because of its good anti-reconnaissance and anti-interference characteristics. It is known that the bistatic PRI-agile radar's detection and estimation performance of high-speed target can be improved by signal integration. However, due to the high speed and maneuvering characteristics of the target, the integration processing is confronted with problems such as RM, DFM, and scale effect, which would lead to a reduction in integration performance. Therefore, we present a coherent integration method named NU-SCGRFT for high-speed maneuvering target detection and estimation with bistatic PRI-agile radar in this article. First, we establish the target's equivalent motion model, which considers both the intrapulse and the interpulse motion of the target, and analyze the characteristic of the received signal and the mismatch effect of the traditional pulse compression. Then, the definition of the NU-SCGRFT method is given, and the processes of intrapulse integration and interpulse integration are derived. Thereafter, the signal processing flow based on the NU-SCGRFT method is given. Finally, through detailed simulation experiments, we compare and analyze the integration, detection, and parameter estimation performance of the proposed algorithm. The result shows that NU-SCGRFT has good integration and parameter estimation performance in bistatic PRI-agile radar system.

Meeting the damage tolerance requirements for engineering-grade titanium alloys pose a significant challenge in achieving high fracture toughness in direct energy deposition (DED) titanium alloys. This work primarily investigated the relationship between the microstructure and the fracture toughness of DED new Ti-6Al-4V-1Mo alloy. Two types of microstructures were designed via two process strategies: high-line energy density (HE) and low-line energy density (LE). Relative to LE samples, HE samples possess larger-sized microstructural characteristics (coarser grain boundary α(αGB), larger αcolonies, and coarser αlaths). Less α/βphase boundaries were formed by coarser αlaths in the HE samples, increasing the movement of dislocations, resulting in tensile strength decreasing from 1007.1 MPa (LE) to 930.8 MPa (HE) and elongation increasing from 10.8% (LE) to 15.7% (HE). Also, HE samples exhibited an excellent fracture toughness of 114.0 MPa m1/2, significantly higher than that of LE samples (76.8 MPa m1/2). An analysis of crack propagation paths was conducted to investigate the factors contributing to toughening. The primary factor enhancing toughness is the frequent obstruction of cracks by coarse αGBand large αcolonies in HE samples. Particularly, the pretty large-angle deflections induced by the superposition effect of coarse αGBand large αcolonies play a vital of significant role. These factors induced the long and tortuous high-energy pathways, which resulted in ultimately improved fracture toughness. The discovered microstructural toughening mechanisms can serve as a reference for future studies involving titanium alloys, offering insights on how to enhance fracture toughness by achieving similar characteristics.

Owing to their large specific surface areas and excellent heat and mass transfer compared with those of conventional batch reactors, microreactors have been widely used in chemical industries. In this study, a strategy is proposed for precisely controlling the synthesis of comb-type terpolymers in a microreactor. Poly(octadecyl acrylate–docosyl acrylate–maleic anhydride) was investigated as a pour point depressant (PPD) for waxy crude oils. A terpolymer showing a high weight-average molecular weight (Mw) and low polydispersity index (PDI) was synthesized within 5 min compared with a conventional time-consuming batch reaction. Under the optimal conditions, the Mwof the terpolymer reached 3.7 × 104, and the PDI was 1.42. Notably, the pour point of the crude oil was reduced by 8 K at a PPD dosage of 1300 ppm. The polymerization kinetics revealed that the microreactor accelerated the polymerization. In contrast to the batch reactor, the microreactor exhibited better heat transfer, which avoided the generation of hot spots. Furthermore, the calculated Bodenstein number (Bo) revealed that the degrees of plug-flow deviation and backmixing are negatively correlated with the molecular weight distribution.

Cadmium (Cd) contamination in agricultural soils is a major environmental threat due to its toxicity and persistence. Nano-montmorillonite (NMMT) has shown promising potential for remediating Cd-contaminated soils. However, the combined effect of NMMT and plant roots on Cd immobilization and rhizosphere bacterial response is not known. In this study, a multi-compartmental rhizobox was designed with nano-montmorillonite and oilseed rape to investigate the effects of the combined application on cadmium remediation. Our study includes how this approach influences the structure and function of rhizosphere bacterial communities, with a focus on soil physicochemical properties and microbial characteristics. The application of NMMT and plant root system significantly reduced the effective soil Cd content, with a remarkable reduction of 26.72 % observed in the near rhizosphere area. This integrated approach effectively improve the rhizosphere soil microenvironment, demonstrating the beneficial interaction between NMMT and plant root system. In the NMMT-modified soil, the growth and proliferation of rhizosphere functional bacteria were promoted. This promotion favored the bacteria's ability to resist cadmium stress, thus further immobilizing cadmium. This study not only enhances our comprehensive understanding on the role of NMMT in heavy metal pollution control, but also promotes the nano soil remediation technologies and the evaluation of their environmental effects, providing both theoretical support and technical support.

ABSTRACTMacroautophagy is a highly conserved eukaryotic cellular pathway involving the engulfment of macromolecules, organelles, and invading microbes by a double-membrane compartment and subsequent lysosomal degradation. The mechanisms that regulate macroautophagy, and the interaction of its components with other cellular pathways, have remained unclear. Here, we performed proximity-dependent biotin identification (BioID) on 39 core human macroautophagy proteins, identifying over 700 unique high confidence proximity interactors with new putative connections between macroautophagic and essential cellular processes. Of note, we identify members of the OSBPL (oxysterol binding protein like) family as Atg8-family protein interactors. We subsequently conducted comprehensive screens of the OSBPL family for LC3B-binding and roles in xenophagy and aggrephagy. OSBPL7 and OSBPL11 emerged as novel lipid transfer proteins required for macroautophagy of selective cargo. Altogether, our proximity interaction map provides a valuable resource for the study of autophagy and highlights the critical role of membrane contact site proteins in the pathway.AbbreviationsBioID: proximity-dependent biotin identification; GO: gene ontology; OSBPL: oxysterol binding protein like; VAPA: VAMP associated protein A; VAPB: VAMP associated protein B and C

The solute segregation and redistribution during non-equilibrium rapid solidification using laser additive manufacturing (LAM) process directly influence the microstructure morphology and phase distribution, which in turn affects their mechanical properties. In this work, a laser micro-alloying strategy was utilized to preserve the original solidification microstructure in the considered Ti-9Mo, Ti-9Cr, Ti-9Fe, and Ti-9Ni (wt%) alloys. The addition of different β-stabilizing elements (Mo, Cr, Fe, and Ni) resulted in distinct microstructures: Ti-9Mo and Ti-9Cr alloys exhibited larger grains (∼502 μm and ∼733 μm) and cellular morphologies due to minimum constitutional undercooling at the solid-liquid interface. Because of the increased constitutional undercooling, the Ti-9Fe grains are significantly refined (∼398 μm), showing a dendritic morphology with elongated primary dendrite arms. Ti-9Ni exhibited the highest constitutional undercooling, forming equiaxed dendrites. However, due to the significant consumption of solute atoms by the interdendritic eutectic phase Ti2Ni, the grains did not further refine (∼396 μm). Combined with the temperature field simulation, the solidification conditions of the alloys were determined. In addition, based on the solute partitioning coefficients (k), the different solute redistribution and diffusion behaviors at the solid-liquid interface during the laser micro-alloying process of Ti-9Mo with k> 1 and Ti-9Cr with k< 1 were elucidated, providing essential insights into the formation of typical cellular morphology and enhanced Mo enrichment phenomenon in the Ti-9Mo alloy.

Currently, microbial production is becoming a competitive method for N-acetyl-glucosamine production. As the biosynthesis of N-acetyl-glucosamine originating from fructose-6-P directly competes with central carbon metabolism for precursor supply, the consumption of glucose for cell growth and cellular metabolism severely limits the yield of N-acetyl-glucosamine. In this study, appropriate catabolic division of labor in the utilization of mixed carbon sources was achieved by deleting the pfkAgene and enhancing the utilization of glycerol by introducing the glpKmutant. Glycerol thus mainly contributed to cell growth and cellular metabolism, and more glucose was saved for efficient N-acetyl-glucosamine synthesis. By optimizing the ratio of glycerol to glucose, the balancing of cell growth/cellular metabolism and N-acetyl-glucosamine synthesis was achieved. The resulting strain GLALD-7 produced 179.7 g/L N-acetyl-glucosamine using mixed glycerol/glucose (1:8, m/m) carbon sources in a 5 L bioreactor, with a yield of 0.458 g/g total carbon sources (0.529 g/g glucose) and a productivity of 2.57 g/L/h. Coherent high titer/yield/productivity was obtained, with the highest values ever reported, suggesting that an appropriate catabolic division of labor using mixed glycerol/glucose carbon sources is a useful strategy for facilitating the microbial production of chemicals originating from glucose or metabolites upstream of glycolysis.

The cycloaddition of CO2with epoxide has been a promising way to fix CO2. Developing efficient, low-cost catalysts for this reaction is highly desired. In this paper, we report a novel cocatalyst system that consists of acrylamide and KI for the synthesis of propylene carbonate using CO2and propylene oxide as starting materials. Different amides (i.e., acrylamide, benzamide, nicotinamide, acetamide, N-isopropylacrylamide, N-tert-butylacrylamide, and N,N-dimethylacrylamide) were combined with different potassium halides to investigate their catalysis capability. KI/acrylamide showed the highest efficiency, and a synergetic effect occurred between acrylamide and KI. At the KI: acrylamide ratio of 1:1 (mol/mol) and concentration of 2.5 mol% for both of them (based on PO), the reaction reached a yield of 95.3%. The catalytic system applies to the cycloaddition reaction using different epoxides. The reaction mechanism was proposed.

OSBPL1 encodes the full-length ORP1L and the truncated variant ORP1S. ORP1S is responsible for transferring cholesterol from late endosomes to the plasma membrane to regulate cholesterol efflux by ABCA1 and LDL receptor activity. ORP1L and ORP1S combine to transport cholesterol from late endosomes to the ER and PM, respectively.

The microstructure formation in the Ti64 alloy with the addition of different alloying elements is extensively researched to enhance the mechanical properties of the alloy, especially fabricated using additive manufacturing processes. In this work, the effect of Mo (0, 1, 2, 4 wt%) addition on the microstructure and mechanical properties of the direct energy deposited (DED) Ti64 alloy was evaluated in detail. As the Mo content increases, a remarkable refinement in the α-laths morphology was observed, with the average width decreasing from ∼1.12 μm to ∼0.39 μm, and an anomalous increase in the volume fraction of the α phase was noted in the Ti64–1Mo alloy. Further increase of the Mo content results in the attenuation of the variant dominance of the α-laths until virtually eliminated. Notice that the tensile strength and elongation increased by 7.3% and 37.5% with 1 wt% addition of Mo, respectively. A Laser-Stop (LS) strategy was employed to preserve the formed metastable phases during the DED process. Such LS strategy provides necessary insights into microstructural evolution and elucidates the mechanisms behind the formation of a refined microstructure and in turn its mechanical properties.

Accurate and timely reporting of organizational performance is becoming increasingly important and highly regulated. However, organizations face a variety of challenges in seeking to provide accurate and reliable information due to the existence of IT control problems. Hence it is important for end users including auditors and managers to understand how to manage IT material weaknesses (ITMWs). While there is extensive accounting research on general material weaknesses (MWs), ITMWs are under researched. This article identifies key firm characteristics that appear to be related to ITMWs. In addition, the authors suggest that IT governance may help firms mitigate such problems. To gain a deeper understanding of IT governance effects, this article proposes a model which includes an innovative construct, ITGOV, operationalized using secondary data. The authors empirically validate the proposed model based on a data set of 1,112 firms. Their study illustrates the differences between ITMWs and general MWs. These results can also help end users computing by offering insights into better management of ITMWs.

Lipoprotein cholesterol is delivered to the limiting membrane of late endosomes/lysosomes (LELs) by Niemann-Pick C1 (NPC1). However, the mechanism of cholesterol transport from LELs to the endoplasmic reticulum (ER) is poorly characterized. We report that oxysterol-binding protein-related protein 1L (ORP1L) is necessary for this stage of cholesterol export. CRISPR-mediated knockout of ORP1L in HeLa and HEK293 cells reduced esterification of cholesterol to the level in NPC1 knockout cells, and it increased the expression of sterol-regulated genes and de novo cholesterol synthesis, indicative of a block in cholesterol transport to the ER. In the absence of this transport pathway, cholesterol-enriched LELs accumulated in the Golgi/perinuclear region. Cholesterol delivery to the ER required the sterol-, phosphatidylinositol 4-phosphate-, and vesicle-associated membrane protein-associated protein (VAP)-binding activities of ORP1L, as well as NPC1 expression. These results suggest that ORP1L-dependent membrane contacts between LELs and the ER coordinate cholesterol transfer with the retrograde movement of endo-lysosomal vesicles.

Spontaneous internal carotid artery dissection (ICAD) is a rare disease and an important cause of stroke in young patients. The presentation of ICAD is variable and atypical. We have used three-dimensional T1-weighted volume isotropic turbo spin-echo acquisition to help diagnose ICAD. ICAD should be considered in young patients presenting with relevant symptoms in an emergency setting. We herein report ICAD with an unexplained onset in two patients. Neither had a history of large or small cervical trauma, but both had a history of hypertension. The first patient was a 33-year-old man who presented with upper extremity numbness and mobility impairment, and the second patient was a 40-year-old man with onset of visual impairment. There were no obvious triggers in either case. Both patients were diagnosed with ICAD by blood vessel examination. However, their prognoses differed. The first patient recovered after endovascular therapy, whereas the second patient was successfully managed with medical treatment. ICAD can cause different symptoms depending on where the dissection occurs. Clinicians must be aware of the different clinical manifestations of ICAD, make the correct diagnosis in a timely manner, make appropriate treatment plans according to the patient’s condition, and strive for timely recanalization of the blood vessels.

E-business has seen significant growth over the past few years. To fully realize the benefits of e-business, common standards are required to define the syntax and semantics of Web-based information sharing among firms. Recently, numerous vertical standards developing organizations (SDO) have emerged to develop e-business standards. From a standard making perspective, this paper identifies the uniqueness of vertical e-business standards, explains why the consortium-based mechanism is popular among vertical e-business standardization projects and overviews the existing literature on consortia-based standardization. Based on literature reviews and anecdotal vertical e-business SDO cases, we propose a participant-technical content-institutional structure framework, which lays a foundation for vertical e-business SDO research and points out future research opportunities.

Electrochemical nitrogen reduction reaction (NRR) has been considered as an appealing and sustainable method to produce ammonia from N2under ambient conditions, attracting increasing interest. Limited by low solubility of N2in water and high stability of NN triple bond, developing NRR electrocatalysts with both strong N2adsorption/activation and high electrical conductivity remain challenging. Here, we demonstrate an efficient strategy to develop NRR electrocatalyst with synergistically enhanced N2adsorption/activation and electrical conductivity by heteroatom doping. Combining computational and experimental study, the DFT-designed Ti-doped SnO2exhibits significantly enhanced NRR performance with ammonia yield rate of 13.09 μg h−1 mg−1at −0.2 V vs. RHE. Particularly, the Faradaic efficiency reaches up to 42.6%, outperforming most of Sn-based electrocatalysts. The fundamental mechanism for improving NRR performance of SnO2by Ti doping is also revealed. Our work highlights a powerful strategy for developing high-activity electrocatalysts for NRR and beyond.

We investigate the usage of an adaptive method, the Iterative Adaptive Approach (IAA), in combination with a maximum a posteriori (MAP) estimate to reconstruct high resolution SAR images that are both sparse and accurate. IAA is a nonparametric weighted least squares algorithm that is robust and user parameter-free. IAA has been shown to reconstruct SAR images with excellent side lobes suppression and high resolution enhancement. We first reconstruct the SAR images using IAA, and then we enforce sparsity by using MAP with a sparsity inducing prior. By coupling these two methods, we can produce a sparse and accurate high resolution image that are conducive for feature extractions and target classification applications. In addition, we show how IAA can be made computationally efficient without sacrificing accuracies, a desirable property for SAR applications where the size of the problems is quite large. We demonstrate the success of our approach using the Air Force Research Lab's "Gotcha Volumetric SAR Data Set Version 1.0" challenge dataset. Via the widely used FFT, individual vehicles contained in the scene are barely recognizable due to the poor resolution and high side lobe nature of FFT. However with our approach clear edges, boundaries, and textures of the vehicles are obtained.