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Understanding the stamping behavior of cast-rolled AZ31 magnesium alloy sheets at room temperature is helpful to promote its deep processing application. The research object selected in this paper is a variable-curvature shell with complex geometric features. The purpose is to investigate the effects of blank shape, blank holder force (BHF), and die clearance on the formability of cast-rolled AZ31 magnesium alloy shells, and to further clarify under reasonable process conditions defects that are prone to occur in the shell characteristic areas and limit the forming height of the shells. The results show that the proportion of the safety zone is obviously affected by the process conditions. It appears that the blank shape when approaching the cross-section of the shell is beneficial to improve the safety zone ratio. When the BHF is 65 kN and die clearance is 3 mm, the safety zone ratio will reach the maximum proportion of ~ 39.61%. During the stamping, there are obvious differences in defect formation between different characteristic areas. They are prone to crack in both the punch corner area and the die corner area, form insufficiently in the bottom zone and the transition zone, and form shear fractures in the flange area. The forming limit height of the variable-curvature shell has been determined to be ~ 13 mm. [ABSTRACT FROM AUTHOR]

Herein, Cu3P was used as a co-catalyst to improve the separation efficiency of photogenerated carriers in WSe2 photocatalysts. The metallic nature of Cu3P and its noble metal-like properties make it an affordable and efficient co-catalyst. The experimental results revealed that the photocatalytic activity of the WSe2/Cu3P (WP) sample was significantly higher under visible light with an average hydrogen evolution rate (HER) of 616.50 μmol h−1 g−1 and a quantum yield of 23.75%. In contrast, the average HER of the pure WSe2 sample was only 298.46 μmol h−1 g−1. The preparation parameters were optimized by a single-factor test. The optimal preparation parameters were as follows. The loading of Cu3P was 8%, and the calcination time and temperature were 2.0 h and 300 °C, respectively. An innovative exploration of the photocatalytic memory effect of WP photocatalyst was carried out. The analysis of the experimental results displayed that the HER of the WP photocatalyst under dark conditions reached 418.50 μmol h−1 g−1 after 5.0 h post-illumination. [ABSTRACT FROM AUTHOR]

Poor-quality sheet sections and excessive burrs may be resolved by incorporating ultrasonic vibration into the shearing process of hard-to-deform magnesium alloy sheets. It is challenging to simulate the complicated mechanical process of ultrasonic shearing process because it involves material deterioration and fracture, elastic–plastic deformation of the material, and the impacts of ultrasonic indirect sexual contact. Relying on ABAQUS/Explicit finite element simulation software, this paper for the first time proposes a boundary constraint method of constructing a converter to connect displacement reference points and vibration reference points in order to perform numerical simulation of the ultrasonic shearing process of AZ31B magnesium alloy. The team's ultrasonic vibration system serves as the basis for the simulation's shearing model. This model utilizes three variables, namely sheet temperature, shear edge clearance, and ultrasonic amplitude, to analyze the weight coefficients and the influence law on the equivalent stress using the orthogonal test in order to further characterize the processing characteristics of ultrasonic shearing. This research demonstrates that numerical simulation is an effective method for examining the influence of process parameters on stress distribution. The results showed that in the ultrasonic shearing of AZ31B magnesium alloy sheet, the process parameter with the greatest influence on the weight coefficient was the sheet temperature, which was 49.8667, followed by the shear edge clearance, which was 31.2667, and the ultrasonic amplitude, which was 17.5333. When the sheet temperature is 150 ℃, the optimization effect is maximal, and the equivalent stress is reduced by 63.9 MPa. Under identical conditions, ultrasonic shearing substantially reduces the equivalent stress on the sheet compared to conventional shearing. During the ultrasonic shearing procedure, the equivalent stress of the sheet appears to be stress superposition and stress fluctuation, resulting in a significant improvement in sheet section quality. As a result, the paper can serve as a quantitative guide for predicting the ultrasonic shearing quality of the AZ31B magnesium alloy sheet. [ABSTRACT FROM AUTHOR]

The increasing demand for electronic devices in the environmental and medical fields has attracted considerable attention regarding their fabrication. As a new type of passive nanoelectronic information device, memristors have been widely used in the fields of information storage, logic operation, and neural networks due to their special electrical properties. However, the selection of new materials, the device fabrication methods, and the improvement of memory performance need further research. In this work, Bi2Te3 memristors were prepared by the hydrothermal synthesis of Bi2Te3 as a resistive dielectric layer material. The properties of the sample were analyzed using SEM, XRD, and XPS characterization methods. The Bi2Te3 memristors were also tested for their performance and stability using an electrochemical workstation, and the results showed that the Bi2Te3 memristors had good performance. Further analysis of the memristive mechanism showed that the resistive mechanism of Bi2Te3 memristors is an interaction of the conducting wire mechanism and the space charge-limited current mechanism. [ABSTRACT FROM AUTHOR]

The forming properties of AZ31 magnesium alloy plates were obtained by tensile tests, using Autoform software to simulate the room-temperature stamping process of AZ31 magnesium alloy. And orthogonal experiments were explored on the variable-curvature plate shell parts of AZ31 magnesium alloy in order to investigate the influence of various forming parameters. The conditions of 14.41% sufficient forming with blank-holder force, clearance between punch and die, the resistance coefficient of drawbead, and the coefficient of friction were clarified. The results suggest that the blank-holder force plays a preponderant role in the maximum thinning rate of the room-temperature stamping formability of AZ31. Additionally, the study found that the curvature of the punch radius is negatively associated with the average thinning rate. In order to promote the flow of metal around the punch radius and to improve the forming uniformity and ultimate forming depth, it is necessary to reduce the curvature of the punch radius to reduce the stress concentration at the punch radius. [ABSTRACT FROM AUTHOR]

Herein, an intrinsic porous light biomass is utilized as an environmentally friendly precursor to prepare high value-added porous carbon as the interlayer material for advanced lithium sulfur (Li–S) batteries. Various material characterization methods are utilized to investigate the obtained porous carbon and found that it exhibits three-dimensional interconnected porous structures with the characteristics of defective graphite structure. Its specific surface calculated by BET method is 300.4 m2 g−1. It can productively curb polysulfide shuttle and boost the cycling performance and rate capability of the battery. The first capacity of Li–S battery with this porous carbon is 905.6 mAh g−1 at 1 C, and it maintains 464.8 mAh g−1 even over 500 cycles. More significantly, special microstructures derived from natural growth avoid complicated preparation processes, and it opens up new alternatives for Li–S batteries. [ABSTRACT FROM AUTHOR]

A novel low-cost Mg-Al-Ca-Zn-Mn-based alloy was developed to simultaneously improve its strength and ductility. The high yield strength of 411 MPa and the high elongation to failure of ∼8.9% have been achieved in the as-extruded Mg-1.3Al-1.2Ca-0.5Zn-0.6Mn (wt%) sample. Microstructure characterizations showed that the high strength is mainly associated with the ultra-fined dynamically recrystallized (DRXed) grains. Moreover, high-density dislocations in the un-DRXed region and nano-precipitates are distributed among the α-Mg matrix. The high ductility property can be ascribed to the high volume fraction of DRXed grains with a much randomized texture, as well as the formations of high-density subgrains in the un-DRXed grain regions. [ABSTRACT FROM AUTHOR]

In-plane birefringent materials present an effective modulation of the optical properties and more degrees of freedom for the signal detection in low dimension, and thus remain a hot topic in realizing the integrated, miniature, and flexible devices for multiple applications. Here, the artificial in-plane birefringence properties have been successfully achieved on a graphene oxide film by a novel femtosecond laser lithography method, which provides a high-speed, large-area, and regular subwavelength gratings (∼ 380 nm) fabrication and photoreduction. The obtained sample manifests an evident optical birefringence (∼ 0.18) and anisotropic photoresponse (∼ 1.21) in the visible range, both of which can be significantly modulated by either the structural morphology or the degree of oxide reduction. Based on the analysis of effective-medium theory and measurements of angle-resolved polarized Raman spectroscopy, the artificial in-plane birefringence is originated from various optical responses of the periodic subwavelength structures for the incident light with different polarization states. This technique shows great advantages for the fabrication of integrated in-plane polarization-dependent devices, which is expected to solve the problems in this field, such as the deficient selection of materials, complex design of micro/nanostructure, and inflexible processing technology. [ABSTRACT FROM AUTHOR]

The phenomenon that longstanding impaired olfactory function is associated with the decreased gustatory function was described in present studies, which was seems attributed to mutual chemosensory interactions. And the interaction between olfaction and gustation still needs more research to figure out. The objective of the study was to investigate how the taste was influenced by olfactory impairment in the central pathway. We tested 33 subjects with normal (n = 19) or impaired (n = 14) olfactory function for their gustatory event-related potentials (gERPs). Validated tests were used for olfactory and gustatory testing (Sniffin' Sticks, gERPs, and three-drop test). This study reported an objective gustatory function decline in olfactory dysfunction participants. However, it also reported the increased gustatory event-related potentials of olfactory dysfunction participants, especially at the frontal electrode (FZ) and electrode 16 (E16), and the reduced latency of P2 peak of them at electrode 21 (E21), while no obvious difference was observed at the centro-parietal electrode (PZ). Inferior insula might be the main response area for the increase in gERPs, and this increase averaged amplitude of the P2 component may attribute to compensation of the secondary gustatory response that occurred in the gustatory processing of olfactory-impaired patients. [ABSTRACT FROM AUTHOR]

Introduction : Glioblastoma (GBM) is a complex disease with high intratumoral heterogeneity, understanding the molecular characteristics of intratumoral heterogeneity accurately is the basis for precision treatment. Although the existing typing strategy based on tumor molecular characteristics has a positive effect, there is still room for improvement, which is mainly because the traditional typing is completed based on the sequencing data of tissue samples, that is, the obtained data are the average level of patient tumor tissues, masking the intratumoral heterogeneity of a single patient and cannot reflect the real level of patient tumor cells. At present, cancer molecular typing is mostly performed based on transcriptome (RNA-seq) without considering lncRNA molecules that are also tissue-specific and developmental stage-specific. Therefore, in this study, we used lncRNAs as typing markers and combined single-cell expression profiles to retype glioblastoma, providing new ideas for GBM molecular typing, and further analyzed the shortcomings of traditional therapies at the singlecell level based on typing results and proposed new precise therapeutic insights. Methods: We downloaded GBM single-cell sequencing data from GSE84465 and performed a series of preprocessing. The intratumoral heterogeneity of patients at the single-cell level was revealed using t-SNE, and the room for improvement of the existing traditional histotyping method was revealed using heat map and density curve. Subsequently, to validate the feasibility of lncRNA typing, we compared the similarities and differences of expression patterns between lncRNAs and mRNAs in GBM cells. Then, we used the R package "Seurat" to perform unsupervised clustering of GBM cells for re-typing and performed a detailed analysis of the biological characteristics of each subtype, including differentially expressed lncRNAs and marker lncRNAs. For validation, we performed survival analysis on GBM tissue data from the TCGA database to reveal the impact of different subtypes on patient survival prognosis. Eventually, based on the results, we screened the therapeutic drugs of each subtype by targeting the downstream regulatory genes of lncRNAs and proposed a new precision therapeutic strategy. Results: GBM has significant intratumoral heterogeneity at the single-cell level, with more than one traditional subtype highly expressed in each patient, which reflects the shortcomings of traditional histotyping. LncRNAs and mRNAs have similar expression patterns in GBM cells, and the expression coefficient of variation of lncRNAs is higher than that of mRNAs, meaning that lncRNAs will better reflect the intratumoral heterogeneity. GBM was reclassified into four subtypes by unsupervised clustering, with different subtypes having different biological characteristics. Survival analysis showed that patients with different subtype compositions had different prognostic outcomes, so different subtypes had different effects on patient prognosis. Based on this, 47 drugs were screened for treatment. There are both shared and unique drugs between different subtypes. A new precision treatment strategy was proposed: for patients with different subtypes, in addition to the combination of drugs targeting single subtype, drugs targeting multiple subtypes can also be selected. Conclusion: Intratumoral heterogeneity may lead to poor prognosis or recurrence after treatment, and more precise typing of GBM can be performed based on single-cell lncRNA expression profiles. The biological characteristics possessed by different subtypes will have different effects on patients, such as survival time. For different subtypes, there are both drugs targeting single subtype and drugs targeting multiple subtypes, and we prefer drugs targeting multiple subtypes because this strategy can maximize medication efficiency and reduce the types of medication to reduce risks and side effects. [ABSTRACT FROM AUTHOR]

A low-cost and high-strength Mg-Al-Ca-Zn-Mn-Ce-based alloy sheet has been developed and fabricated by single-pass large-strain rolling process. Effects of rolling temperatures on the microstructure and mechanical properties of the Mg sheets have been investigated. The results show that the grain sizes of the Mg sheets are remarkably refined to be ~ 1.5 and ~ 0.8 µm after rolling at 350 and 250 °C (denoted as X-350 and X-250), respectively. The fine nano-precipitates are found to distribute both within the grain interiors and along the grain boundaries. co-segregations of Ca and Zn atoms also readily occur in present Mg sample, and the solute concentration increases with the decrease in rolling temperature. Nano-precipitates and solute segregations can effectively impede the grain growth and contribute to the grain refinement in as-rolled Mg samples. Optimal mechanical properties have been obtained in X-250 sheet rolled at 250 °C, exhibiting the YS, UTS and EL of ~ 290 MPa, ~ 304 MPa and 11.6%, respectively. The ultra-fine grains, solute segregations and the intensified basal texture play the critical roles together. [ABSTRACT FROM AUTHOR]

The hexagonal close-packed (HCP) to face-centered cubic (FCC) phase transition has recently been identified in commercial purity titanium under cryogenic plane-strain compression or conventional rolling. To verify whether the shear deformation could induce this unique HCP-to-FCC phase transition or not, we performed equal channel angular drawing (ECAD) on pure Ti and observed the microstructure changes after deformation by transmission electron microscopy. The results show that the ECAD deformation can induce this phase transition easily. The orientation relationship between the HCP matrix and FCC phase is the well-known prismatic relation 0001HCP//001 and 101¯0HCP//11¯0FCC after ECAD at room temperature. Meanwhile, the FCC-Ti phase processed by ECAD exhibits a high thermal stability with a transus temperature of about 600 °C according to the differential scanning calorimetry technique and annealing tests. However, the FCC-structured Ti has unexpectedly poor stability under high-energy electron beam irradiation, and the FCC-to-HCP reverse transition is attributed to the shear-shuffle mechanism. [ABSTRACT FROM AUTHOR]

To investigate whether and how organic anion transporter 1 (OAT1) is involved in the process of Alzheimer's disease (AD), we crossbred OAT1 knockout mice with tg2576, the widely used AD model mice. Results here showed the heterozygous OAT1-deficient tg2576 mice developed a learning- and memory-related behavior deficiency and higher soluble Abeta amount in early stage (3 months old). Furthermore, the heterozygous mice brain slice also showed impaired long-term potentiation (LTP) and spontaneous excitatory postsynaptic currents (sEPSC). By crossbreeding heterozygous OAT1-deficient tg2576 mice with Thy-1 YFP mice, we got autofluoresced (layer 4/5 cortical neuron) heterozygous mice. By using two-photon microscope in the direct observation of mice brain in vivo or single photon confocal on slices, compared with control tg2576 mice, we found that the OAT1-deficient mice showed a higher spine numbers but with a much lesser maturity extent. Finally, by using glutamate uncaging method, we induced chemical LTP in brain slices and found that OAT1-deficient mice showed abnormal chemical-induced LTP, which meant that the deficient behavior may be caused by abnormal spine morphology and activity. Our results indicated OAT1 may be involved in AD process by regulating spine morphology and activity. [ABSTRACT FROM AUTHOR]

To investigate whether uric acid could regulate urate transporter 1 (URAT1) protein and activity level, we established uric acid nephropathy (UAN) rat model and detected their serum uric acid and URAT1 level with or without the treatment of allopurinol. Results here showed that allopurinol could reduce serum uric acid level in UAN rat model. We further found that in UAN rats, the total and surface URAT1 expression level were both increased while this increase could be blocked by allopurinol treatment. By treating URAT1 stable expressed HEK cell with monosodium urate (MSU) crystals, we found that URAT1 level showed an increase in both total and cell surface level, and it would colocalize more with Rab11 instead of Rab7. Consistently, we also found that the total URAT1 protein level will show an increase in the presence of lysosome inhibitors but not ubiquitin-proteasome inhibitors. Furthermore, we also found that MSU crystal could drive Numb, a clathrin-coated adaptor protein which performs a key function in cell division, out of cell surface and disassociated it from URAT1. Finally, we found that Numb short hairpin RNA (shRNA)-transfected showed a phenocopy as MSU treatment, while Numb-2A mutation over-expression could resist crystal-induced phenotypes. These findings indicated that uric acid crystal could increase URAT1 membrane distribution through inhibiting Numb-induced URAT1 lysosome degradation. [ABSTRACT FROM AUTHOR]

Carbon soot containing fullerene was continuously produced in volume by pyrolyzing acetylene in thermal HF-Plasma. The characteristics of the carbon soot and C60 were analyzed by thtransmission electron microscopy, UV/visible, IR and Raman spectroscopy. The results show that the main ingredients of the carbon soot with size of about 25 nm are amorphous carbon, graphite and fullerene. The fullerene yield in carbon soot is about 2.5 g·h−. Compared with the graphite arc discharge method, the acetylene thermal plasma method is a preferential one for synthesis of fullerene. [ABSTRACT FROM AUTHOR]