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The 2H‐MoTe2 is a well‐known layered 2D semiconductor that is considered as a promising material for next‐generation microelectronic and optoelectronic devices. Te‐deficiency‐induced defective structures, like Te vacancy and mirror twin boundary (MTB), would be generated at elevated temperatures. However, the temperature‐dependent evolution of such defects and their influence on the macroscopic electrical transport property of 2H‐MoTe2 is unclear. Herein, the semiconductor–metal transition phenomenon in 2H‐MoTe2−x mediated by the evolving disordered MTB network with increasing Te deficiency is reported on. The samples are grown by molecular beam epitaxy, while the Te deficiency is tuned by post‐growth flash annealing in ultra‐high vacuum. Low‐temperature scanning tunneling microscope investigation discloses the medium‐range disorder evolution of the MTB network incorporated in the 2H‐MoTe2, which eventually transforms to an ordered metallic Mo5Te8 metastable phase. The scanning tunneling spectroscopy shows rich in‐gap states localized at the MTBs, which provide a conducting channel in the semiconductor. The ultra‐high vacuum in situ transport measurement shows a gradual decrease of resistance of the sample upon flash annealing from 50 to 480 °C, confirming the influence of Te deficiency on the transport property, which would play an essential role in the device performance and durability.

Abstract Plastid ribosomal proteins play a crucial role in the growth and development of plants, mainly in the gene expression and translation of key genes in chloroplasts. While some information is known about the regulatory processes of plastid ribosomal proteins in various plant species, there is limited knowledge about the underlying mechanisms in rice. In this study, ethyl methanesulfonate (EMS) mutagenesis was used to generate a new mutant called wlp3 (white leaf and panicle3), characterized by white or albino leaves and panicles, which exhibited this phenotype from the second leaf stage until tillering. Furthermore, after a certain period, the newly emerging leaves developed the same phenotype as the rice variety ZH11, while the albino leaves of wlp3 showed an incomplete chloroplast structure and significantly low chlorophyll content. A transition mutation (T to C) at position 380 was identified in the coding region of the LOC_Os03g61260 gene, resulting in the substitution of isoleucine by threonine during translation. WLP3 encodes the ribosomal L18 subunit, which is localized in the chloroplast. Complementation experiments confirmed that LOC_Os03g61260 was responsible for the albino phenotype in rice. WLP3 has high expression in the coleoptile, leaves at the three-leaf stage, and panicles at the heading stage. Compared to the wild-type (WT), wlp3 exhibited reduced chlorophyll synthesis and significantly decreased expression levels of genes associated with plastid development. Yeast two-hybrid (Y2H) analysis revealed that WLP3 interacts with other ribosomal subunits, to influence chloroplast development. These results contribute to a better understanding of the underlying molecular mechanisms of chloroplast development and plastid gene translation.

Heavy metals in water bodies pose a significant threat to both ecology and human well-being. Therefore, the development of green and sustainable adsorbents for water remediation is essential. This study presents a crosslinked chitosan composite structure with multiple layers, which was generated by adjusting the ratio of chitosan to wheat straw–derived magnetic biochar in the composite. The adsorption behavior of the composite under different conditions was revealed by varying the Cr(VI) concentration, pH, and temperature. The composite exhibited a maximum adsorption of 121.8 mg g−1 for Cr(VI) in water, which was 11.9 times higher than that of magnetic biochar. It maintained a residual performance of 78.6 % after seven cycles, higher than most chitosan-based composites. The reusability was improved via hydrochloric acid protonation of functional groups and layer-by-layer exposure of the composite structure. This study provides new insights into the application of composites derived from chitosan and wheat straw, an agricultural waste, as sustainable adsorbents.

IntroductionThe severity of flood disasters is increasing due to climate change, resulting in a significant reduction in the yield and quality of forage crops worldwide. This poses a serious threat to the development of agriculture and livestock. Hemarthria compressa is an important high-quality forage grass in southern China. In recent years, frequent flooding has caused varying degrees of impacts on H. compressa and their ecological environment.MethodsIn this study, we evaluated differences in flooding tolerance between the root systems of the experimental materials GY (Guang Yi, flood-tolerant) and N1291 (N201801291, flood-sensitive). We measured their morphological indexes after 7 d, 14 d, and 21 d of submergence stress and sequenced their transcriptomes at 8 h and 24 h, with 0 h as the control.ResultsDuring submergence stress, the number of adventitious roots and root length of both GY and N1291 tended to increase, but the overall growth of GY was significantly higher than that of N1291. RNA-seq analysis revealed that 6046 and 7493 DEGs were identified in GY-8h and GY-24h, respectively, and 9198 and 4236 DEGs in N1291-8h and N1291-24h, respectively, compared with the control. The GO and KEGG enrichment analysis results indicated the GO terms mainly enriched among the DEGs were oxidation-reduction process, obsolete peroxidase reaction, and other antioxidant-related terms. The KEGG pathways that were most significantly enriched were phenylpropanoid biosynthesis, plant hormone signal transduction etc. The genes of transcription factor families, such as C2H2, bHLH and bZIP, were highly expressed in the H. compressa after submergence, which might be closely related to the submergence adaptive response mechanisms of H. compressa.DiscussionThis study provides basic data for analyzing the molecular and morphological mechanisms of H. compressa in response to submergence stress, and also provides theoretical support for the subsequent improvement of submergence tolerance traits of H. compressa.

Acoustic waves are essential tools for guiding underwater activities. For many years, numerical modeling of ocean acoustic propagation has been a major research focus in underwater acoustics. Normal mode theory, one of the earliest and most extensively studied methods in this field, is renowned for its well-established theoretical framework. The core of normal mode theory involves the numerical solution of modal equations. In classical normal mode models, these equations are typically discretized using low-order finite difference methods, which, while broadly applicable, suffer from a limited convergence rate. The spectral element method, widely used in the seismic field, is recognized for its spectral precision and flexibility. In this article, we propose a normal mode model discretized using the spectral element method. The weak form of the modal equation directly satisfies boundary and interface conditions without requiring additional operations. The entire computational domain can be divided into segments of varying number and length, configured according to environmental conditions. The perfectly matched layer technique is employed to simulate acoustic half-space boundary conditions, effectively addressing the high computational costs and numerical instability associated with traditional artificial absorbing layers. Based on these algorithms, we have developed a numerical program (SEM). This research verifies the accuracy of the spectral element model through three different types of numerical experiments.

The avionics network supports high-safety-level flight operations, with the analysis of transmission failures serving as a crucial means for its safety evaluation. Due to the time-dependent nature of the failure probability in avionics networks, traditional constant and unchangeable probability values can deviate from the actual situation under specific conditions. This deviation may lead to inadequate responses to occasional events and potentially cause flight accidents. A Dynamic Fault Tree (DFT) model for civil aircraft avionics network transmission failures, based on an optimized extended fuzzy algorithm, is introduced in this paper. Initially focusing on event correlations, a DFT is established for the transmission failure of the Avionics Full Duplex Switched Ethernet (AFDX). Subsequently, considering the variations between events, triangular fuzzy processing is applied to the event failure rates based on relative confidence levels. Finally, by optimizing the weakest t-norm operator, the failure probability intervals are aggregated and the fuzzy scale is regulated. Experimental results demonstrate that, compared to the static-minimum t-norm and traditional weakest t-norm methods, the proposed approach enhances the accuracy of the fuzzy failure probability intervals by 66.15% and 40.59%, respectively. Concurrently, it maintains consistency in the ranking of event importance, highlighting the superior effectiveness of the proposed method in analyzing transmission failures in avionics networks.

The immune microenvironment plays a pivotal role in osteoanagenesis. Biomaterials can modulate osteogenic efficacy by inducing specific local immune reactions. As 3D-printing technology advances, digital light projection printing has emerged as a promising method for creating large scale, high-precision biomaterial scaffolds. By adjusting the solid content and the sintering conditions during printing, the pore size of biomaterials can be meticulously controlled. Yet, the systematic influence of pore size on the immune microenvironment remains uncharted. We fabricated 3D-printed hydroxyapatite bioceramic scaffolds with three distinct pore sizes: 400 μm, 600 μm, and 800 μm. Our study revealed that scaffolds with a pore size of 600 μm promote macrophage M2 polarization, which is achieved by upregulating interferon−beta and HIF-1α production. When these materials were implanted subcutaneously in rats and within rabbit skulls, we observed that the 600 μm scaffolds notably improved the long-term inflammatory response, fostered vascular proliferation, and augmented new bone growth. This research paves the way for innovative therapeutic strategies for treating large segmental bone defects in clinical settings.

Mass concrete is prone to cracks due to the temperature difference between the inside and outside. In this study, the effects of four factors, including the ambient temperature, initial temperature of concrete after pouring, and cooling water temperature and flow rate, on the variation characteristics of the internal temperature field of mass concrete are investigated using a combination of theoretical, empirical, and numerical simulation analyses. The results show that the service life of concrete can be prolonged by lowering the ambient temperature, lowering initial temperature of concrete after pouring, increasing the cooling water temperature or increasing the cooling water flow rate, which can effectively improve the cooling rate of concrete. The temperature difference between the inside and outside of the concrete can be effectively reduced by increasing the ambient temperature, increasing the cooling water flow rate, lowering initial temperature of concrete after pouring, or lowering the cooling water temperature, thus reducing the possibility of cracks. Through Grey relation analysis, it is found that cooling water temperature is the most important influencing factor that affects the changing characteristics of the internal temperature field of concrete The influencing factor weights can be used to provide theoretical support for subsequent temperature control measures.

Abstract The mantle plumes modify geophysical and geochemical features along and across mid‐ocean ridges. Despite abundant studies of plume‐ridge interaction, few geodynamic studies focus on the Arctic Ocean. The Jan Mayen Hotspot is located at the southern end of the Mohns Ridge and offset by the Jan Mayen Transform Fault, which creates an ideal area to study plume‐ridge‐transform fault interaction at the ultra‐slow spreading ridge. Through analyzing geophysical observations, we revealed that the M factor and crustal thickness decrease and the axial relief increases northeastward along the Mohns Ridge within a distance of ∼370 km to the Jan Mayen Hotspot. Combined with modeling results, the properties of the Jan Mayen plume were estimated, which has a diameter of 75 km, a temperature anomaly of 100°C, and a buoyancy flux of 0.22 Mg/s. Additionally, our model results indicate that the along‐ridge dispersion of plume is slightly enhanced by the transform fault.

The light field display technology can reconstruct the virtual three-dimensional scene with high precision, providing users with a highly immersive viewing experience without any auxiliary equipment. However, one of the main challenges faced by this technology is the narrow field of view (FOV). In this paper, we present a novel autostereoscopic display utilizing Composite Lenticular Lens Array (CLLa) and Saddle Lens Array (SLa). By utilizing time-division quadruplexing, distinct contents are assigned to different pairs of viewing zones. The optical model of this scheme is simulated by ZEMAX. The FOV is expanded horizontally to 100 degrees and the crosstalk level is reduced to 0.8%, ideally. It is worth noting that both viewing zones share the same set of pixels, which theoretically results in a spatial resolution one times higher than traditional schemes. Furthermore, this scheme has been partially verified by a 7.9-inch TFT-LCD screen, and experimental results demonstrate an effective expansion of the field of view angle by more than 16.2% compared to traditional schemes.

Background: Alzheimer’s disease (AD) is a progressive neurodegenerative disorder with cognitive dysfunction and behavioral impairment. We aimed to use principal components factor analysis to explore the association between gait domains and AD under single and dual-task gait assessments. Methods: A total of 41 AD participants and 41 healthy control (HC) participants were enrolled in our study. Gait parameters were measured using the JiBuEn® gait analysis system. The principal component method was used to conduct an orthogonal maximum variance rotation factor analysis of quantitative gait parameters. Multiple logistic regression was used to adjust for potential confounding or risk factors. Results: Based on the factor analysis, three domains of gait performance were identified both in the free walk and counting backward assessments: “rhythm” domain, “pace” domain and “variability” domain. Compared with HC, we found that the pace factor was independently associated with AD in two gait assessments; the variability factor was independently associated with AD only in the counting backwards assessment; and a statistical difference still remained after adjusting for age, sex and education levels. Conclusions: Our findings indicate that gait domains may be used as an auxiliary diagnostic index for Alzheimer’s disease.

Abstract The sub‐nanometer‐diameter transitional‐metal chalcogenides (M6X6) molecular wires are ideal 1D quantum systems. The electronic properties of such system are very sensitive to the interface interaction and local imperfection. Here, the atomic structure and local electronic structure of van der Waals (vdW) stacking Mo6Te6 nanowires fabricated by using molecular beam epitaxy are reported. Atomic‐resolution scanning tunneling microscopy measurement shows that the vdW interface distance varies from 0.71 to 1.05 nm when Mo6Te6 wires stacked on graphite, MoTe2, and Mo6Te6 surfaces. Scanning tunneling spectroscopy confirmed the 1D quantum effect of van Hove singularity and Tomonaga–Luttinger liquid behavior at 77.8 K. Single Te vacancies and their effect to the local structure distortion are observed as well. These observations shed light on the local structure and quantum effects of the M6X6 nanowire materials, which may find applications in future electronic devices.

Depression is common worldwide, and stigmatizing attitudes toward depression have proved to be one of the major barriers to seeking professional help. The purpose of this study was to evaluate the level of personal depression stigma and identify its predictive factors among medical students in Hainan, China, as well as explore the gender difference. A total of 2,186 medical students were recruited using stratified random cluster sampling and interviewed by structured anonymous questionnaires. Personal stigma was measured by the standardized Depression Stigma Scale (DSS). Multivariate linear regression models were used to identify predictors of stigma, and the interactions between gender and each predictor were included to test its gender difference. The mean score on DSS Scale was 13.71 ± 5.35, with males significantly higher than females (14.85 vs 12.99, P < 0.0001). Compared to females, males were more likely to agree with ‘I would not vote for a class cadre if I knew they had been depressed’ and ‘I would not make friends with him if I knew he had been depressed’. Multivariate linear regression analysis revealed that males’ personal stigma was predicted by being only child (ß = 1.01, P = 0.0083), moderate-to-severe depression (ß = 1.12, P = 0.0302), and lower self-rated academic core competitiveness (Competitive: ß = 1.29, P = 0.0088, Not at all/Somewhat competitive: ß = 1.04, P = 0.0381), while females’ personal stigma was only associated with moderate-to-severe depression (ß = 1.75, P < 0.0001). Significant interactions were found between gender and self-rated academic core competitiveness. Stigmatizing attitudes toward depression were prevalent among Chinese medical students, especially male students. Gender differences were found in the predictors of stigma. Effective measures must be taken to reduce the stigma of mental health among Chinese medical students.

An ytterbium-doped, mode-locking fiber front-end laser, delivering both a femtosecond seed laser and picosecond seed laser, was demonstrated. The fundamental repetition rate of the 1031 nm mode-locked laser was 32.77 MHz, realized with the all-polarization-maintaining (all-PM) nonlinear amplifying loop mirror (NALM). The femtosecond seed laser and the picosecond seed laser were delivered after carefully optimizing the nonlinear amplification process. The corresponding pulse durations were 85 fs and 2.88 ps, with average power of 171 mW and 562.5 mW, respectively.

Objective: This review investigates the role of adjuvant therapy (AT) and the importance of histopathological typing in periampullary carcinoma (PAC) treatment. Background: PAC is a relatively rare gastrointestinal malignancy. The regimen and effect of AT in PAC are still controversial. However, there is a treatment based on histopathological types (pancreaticobiliary-type, PB-type or intestinal-type, IN-type), but there are no clear guidelines indicating that typing can be used to guide the selection of AT drugs. Methods: A literature search of PubMed and Web of Science databases was conducted for studies published from January 2001 to August 2021 on the use of AT in PAC. Results: A total of 75 studies were included in this review. According to existing studies, AT for PAC is mostly based on 5-FU or gemcitabine, but the effect is unknown. However, when PAC is classified into different histopathological types, AT with gemcitabine is beneficial for patients with the PB-type of PAC, while 5-FU-based AT is beneficial for patients with the IN-type of PAC. In addition, the benefits of AT are more pronounced in patients with a high-risk disease, such as patients with stage II/III, T3/T4 tumors, or positive lymph node involvement. There are few studies on targeted therapy and immunotherapy for PAC. Conclusions: This review suggests that AT has potential survival benefits, especially when based on the histopathologic type that helps the choice of drugs during AT in PAC patients.

High-performance chrome-free leather production is currently one of the most concerning needs to warrant the sustainable development of the leather industry due to the serious chrome pollution. Driven by these research challenges, this work explores using biobased polymeric dyes (BPDs) based on dialdehyde starch and reactive small-molecule dye (reactive red 180, RD-180) as novel dyeing agents for leather tanned using a chrome-free, biomass-derived aldehyde tanning agent (BAT). FTIR, 1H NMR, XPS, and UV-visible spectrometry analyses indicated that a Schiff base structure was generated between the aldehyde group of dialdehyde starch (DST) and the amino group of RD-180, resulting in the successful load of RD-180 on DST to produce BPD. The BPD could first penetrate the BAT-tanned leather efficiently and then be deposited on the leather matrix, thus exhibiting a high uptake ratio. Compared with the crust leathers prepared using a conventional anionic dye (CAD), dyeing, and RD-180 dyeing, the BPD-dyed crust leather not only had better coloring uniformity and fastness but it also showed a higher tensile strength, elongation at break, and fullness. These data suggest that BPD has the potential to be used as a novel sustainable polymeric dye for the high-performance dyeing of organically tanned chrome-free leather, which is paramount to ensuring and promoting the sustainable development of the leather industry.

During the laser application process, laser energy is usually converted into heat energy, causing high temperature, which affects the (high-speed) aircraft in routine flight. A completely novel photochemical method was investigated to potentially minimize the energy effect of the laser beam. Ag nanoparticles/C3N4 were synthesized by an ultra-low temperature reduced deposit method with Ag mean diameters of 5–25 nm for photofixation of N2. The absorption performance of laser can be improved by using appropriate charge density and small size Ag metal particles. The energy absorption rate was 7.1% over Ag/C3N4 (−40) at 5 mJ/cm2 of laser energy.

A novel laboratory simulation method for modeling multi-staged fracturing in a horizontal well was established based on a true tri-axial hydraulic fracturing simulation system. Using this method, the influences of net pressure in hydraulic fracture, stage spacing, perforation parameter, horizontal stress bias and well cementation quality on the propagation geometry of multiple fractures in a tight sandstone formation were studied in detail. The specimen splitting and analogy analysis of fracturing curve patterns reveals: Multiple fractures tend to merge under the condition of high horizontal stress bias and short stage spacing with pre-existing hydraulic fractures under critical closure situation, and the propagation of subsequent fractures is possibly suppressed because of high net pressure in pre-created fractures and asymmetric distribution of fracture width. And the subsequently created fractures are situated in the induced stress decreasing zone due to long stage spacing, leading to weak stress interference, and perforation with intense density and deep penetration facilitates the decrease of initiation fracture pressure. The deflection angle of subsequent fracture and horizontal stress variation tend to be amplified under low horizontal bias with constant net pressure in fractures. The longitudinal fracture is likely to be initiated at the interface of wellbore and concrete sample with poor cementation quality. The initiation fracture pressure of the different stages increases in turn, with the largest increase of 30%. Pressure quickly declines after initiation with low propagation pressure when the transverse hydraulic fracture is formed. The pressure reduces with fluctuation after the initiation of fracture when the fracture deflects, the extension pressure is high, and the fracture formed is tortuous and narrow. There is a violently fluctuant rise of pressure with multiple peak values when longitudinal fracture created, and it is hard to distinguish the features between the initiation stage and propagation stage. Key words: tight sandstone, horizontal well, multi-staged fracturing, perforation, net pressure in fracture, stress interference between fractures, fracture propagation

Aging is a fundamental biological process accompanied by a general decline in tissue function. Indeed, as the lifespan increases, age-related dysfunction, such as cognitive impairment or dementia, will become a growing public health issue. Aging is also a great risk factor for many age-related diseases. Nowadays, people want not only to live longer but also healthier. Therefore, there is a critical need in understanding the underlying cellular and molecular mechanisms regulating aging that will allow us to modify the aging process for healthy aging and alleviate age-related disease. Here, we reviewed the recent breakthroughs in the mechanistic understanding of biological aging, focusing on the adenosine monophosphate-activated kinase (AMPK), Sirtuin 1 (SIRT1) and mammalian target of rapamycin (mTOR) pathways, which are currently considered critical for aging. We also discussed how these proteins and pathways may potentially interact with each other to regulate aging. We further described how the knowledge of these pathways may lead to new interventions for antiaging and against age-related disease.

As the microporous structure has been widely used in the field of precision machining, at the same time, the requirements for the quality of microporous machining are continuously increasing. Water jet-guide laser processing technology (WJGL) has been gradually applied for its high machining precision. However, there are a few researches on the heat conduction process of WJGL processing metal materials. Therefore, it is of great significance to study the transient thermal effect of metal materials and the mechanism of material removal to improve the processing quality. In order to explore the heat conduction model of WJGL processing metal materials, this paper is based on the “element birth and death” technique in the finite element method, and the three-dimensional transient temperature field of four typical metal materials (titanium alloy, stainless steel, aluminum alloy, copper) and material removal model are established. Under this model, the removal mechanism of different metal materials and the influence of different process parameters on the temperature field distribution of the material are studied, and the influence of fixed-position drilling and helix drilling on the microporous morphology is compared. The results show that copper and aluminum alloys can obtain a larger depth-to-diameter ratio and a smaller hole taper. Titanium alloy and stainless steel have better hole roundness, lower hole edge temperature, and smaller thermal deformation. Hole roundness error and hole taper decrease with the increase of laser power. The roundness error of each material is reduced to within 10 μm when the laser power is 10 W, and the average hole taper is 8.73°.