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Addressing the need for modulated spin configurations is crucial, as they serve as the foundational building blocks for next-generation spintronics, particularly in atomically thin structures and at room temperature. In this work, we realize intrinsic ferromagnetism in monolayer flakes and tunable ferro-/antiferromagnetism in (Fe0.56Co0.44)5GeTe2antiferromagnets. Remarkably, the ferromagnetic ordering (≥1 L) and antiferromagnetic ordering (≥4 L) remain discernible up to room temperature. The TC(∼310 K) of the monolayer flakes sets a record high for known exfoliated monolayer van der Waals magnets. Within the framework of A-type antiferromagnetism, a notable odd–even layer-number effect at elevated temperatures (T= 150 K) is observed. Of particular interest is the strong ferromagnetic order in even-layer flakes at low temperatures. The intricate interplay among magnetic field strength, layer number, and temperature gives rise to a diverse array of phenomena, holding promise not only for new physics but also for practical applications.

Being the main starting point for intelligent transportation systems, internet of vehicles has entered a rapid development period. This motivates a large number of novel vehicular applications with diversified and personalized demands. Distributed collaborative computing provides a promising solution to meet these applications by on-demand resource management, but is faced with tremendous challenges in achieving trusted resource cooperation and accurate decision making. In this paper, we propose a blockchain-based vehicular digital twin architecture for distributed collaborative computing. In this architecture, blockchain facilitates the opening and sharing of vehicular resources, while digital twin enables the accurate management decision. Then, we investigate the computation offloading in blockchain-based vehicular digital twin networks to demonstrate the effectiveness of the proposed architecture. Finally, several important open issues are discussed in detail for further investigation on blockchain-based vehicular digital twin.

In the clades of animals that diverged from the bony fish, a group of Mas-related G-protein-coupled receptors (MRGPRs) evolved that have an active role in itch and allergic signals1,2. As an MRGPR, MRGPRX2 is known to sense basic secretagogues (agents that promote secretion) and is involved in itch signals and eliciting pseudoallergic reactions3–6. MRGPRX2 has been targeted by drug development efforts to prevent the side effects induced by certain drugs or to treat allergic diseases. Here we report a set of cryo-electron microscopy structures of the MRGPRX2–Gi1trimer in complex with polycationic compound 48/80 or with inflammatory peptides. The structures of the MRGPRX2–Gi1complex exhibited shallow, solvent-exposed ligand-binding pockets. We identified key common structural features of MRGPRX2 and describe a consensus motif for peptidic allergens. Beneath the ligand-binding pocket, the unusual kink formation at transmembrane domain 6 (TM6) and the replacement of the general toggle switch from Trp6.48to Gly6.48(superscript annotations as per Ballesteros–Weinstein nomenclature) suggest a distinct activation process. We characterized the interfaces of MRGPRX2 and the Gitrimer, and mapped the residues associated with key single-nucleotide polymorphisms on both the ligand and G-protein interfaces of MRGPRX2. Collectively, our results provide a structural basis for the sensing of cationic allergens by MRGPRX2, potentially facilitating the rational design of therapies to prevent unwanted pseudoallergic reactions.

Over half of mitochondrial proteins are imported from the cytosol via the pre-sequence pathway, controlled by the TOM complex in the outer membrane and the TIM23 complex in the inner membrane. The mechanisms through which proteins are translocated via the TOM and TIM23 complexes remain unclear. Here we report the assembly of the active TOM–TIM23 supercomplex of Saccharomyces cerevisiaewith translocating polypeptide substrates. Electron cryo-microscopy analyses reveal that the polypeptide substrates pass the TOM complex through the center of a Tom40 subunit, interacting with a glutamine-rich region. Structural and biochemical analyses show that the TIM23 complex contains a heterotrimer of the subunits Tim23, Tim17 and Mgr2. The polypeptide substrates are shielded from lipids by Mgr2 and Tim17, which creates a translocation pathway characterized by a negatively charged entrance and a central hydrophobic region. These findings reveal an unexpected pre-sequence pathway through the TOM–TIM23 supercomplex spanning the double membranes of mitochondria.

BackgroundEvaluation of the transverse sinus stenosis (TSS) is essential for TSS-related diseases.ObjectiveTo investigate a new method for the quantitative assessment of TSS based on the correlation between TSS and trans-stenotic pressure gradient (TPG).MethodsPatients with unilateral pulsatile tinnitus with or without idiopathic intracranial hypertension were retrospectively included. All patients underwent CT venography and venous manometry and were confirmed to have TSS. The cross-sectional diameter/area of TSS, the poststenotic and prestenotic segments, and the superior sagittal sinus (SSS) were measured. The degree of TSS was calculated by dividing the diameter/area of TSS by the diameter/area of the poststenotic segment (M1/M2), prestenotic segment (M3/M4), and SSS (M5/M6). Partial correlation analysis (controlling for the effect of age, sex, outflow laterality, and contralateral stenosis) was performed to evaluate the correlation between M1–M6 and the TPG. Receiver operating characteristic curve analysis of M1–M6 for diagnosing a significant TPG (≥8 mm Hg) was performed.ResultsNinety-nine patients met the inclusion criteria. The partial correlation coefficients between M1–M6 and the TPG were 0.60, 0.61, 0.43, 0.48, 0.39, and 0.54, respectively. The areas under the curve (AUCs) of M1–M6 for diagnosing a significant TPG were 0.81, 0.86, 0.68, 0.69, 0.64, and 0.72, respectively. The AUC of M2 was significantly larger than that of M3 (P=0.002), M4 (P<0.001), M5 (P=0.001), and M6 (P<0.001).ConclusionsQuantitatively assessing TSS by taking the ratio of the cross-sectional area of TSS to that of the poststenotic segment might be a more efficient method for predicting the TPG.

Cell division is tightly regulated and requires an expanded energy supply. However, how this energy is generated remains unclear. Here, we establish a correlation between two mitochondrial Ca2+influx events and ATP production during mitosis. While both events promote ATP production during mitosis, the second event, the Ca2+influx surge, is substantial. To facilitate this Ca2+influx surge, the lamin B receptor (LBR) organizes a mitosis-specific endoplasmic reticulum (ER)-mitochondrial contact site (ERMCS), creating a rapid Ca2+transport pathway. LBR acts as a tether, connecting the ER Ca2+release channel IP3R with the mitochondrial VDAC2. Depletion of LBR disrupts the Ca2+influx surge, reduces ATP production, and postpones the metaphase-anaphase transition and subsequent cell division. These findings provide insight into the mechanisms underlying mitotic energy production and supply required for cell proliferation.

Magnetic van der Waals (vdW) materials possess versatile spin configurations stabilized in reduced dimensions. One magnetic order is the interlayer antiferromagnetism in A-type vdW antiferromagnet, which may be effectively modified by the magnetic field, stacking order, and thickness scaling. However, atomically revealing the interlayer spin orientation in the vdW antiferromagnet is highly challenging, because most of the material candidates exhibit an insulating ground state or instability in ambient conditions. Here, we report the layer-dependent interlayer antiferromagnetic spin reorientation in air-stable semiconductor CrSBr using magnetotransport characterization and first-principles calculations. We reveal an odd–even layer effect of interlayer spin reorientation, which originates from the competitions among interlayer exchange, magnetic anisotropy energy, and extra Zeeman energy of uncompensated magnetization. Furthermore, we quantitatively constructed the layer-dependent magnetic phase diagram with the help of a linear-chain model. Our work uncovers the layer-dependent interlayer antiferromagnetic spin reorientation engineered by magnetic field in the air-stable semiconductor.

An effective J-T component is crucial for the operation of dilution refrigerator due to its function as a 3He liquefier in a refrigeration cycle. This paper briefly introduces the principle of the J-T component in dry dilution refrigerator, studies the influence of J-T component on the still and its design method. An effective J-T component is designed to cool over 3 K of 3He gas to almost 1 K of 3He liquid. The basic still temperature is below 0.5 K in a dilution refrigerator prototype. In this prototype, a two-stage step heat exchanger was adopted to obtain the lowest temperature below 26 mK.

As an excellent paramagnetic material with low Curie temperature, Chromium Potassium Alum (CPA) is commonly used in the adiabatic demagnetization refrigerator (ADR) to achieve extremely low temperatures. A typical ADR consists of many components, such as a salt pill, a superconducting magnet, a heat switch, etc. An experimental system was built to test the performance of a single-stage ADR we designed. A two-stage GM refrigerator was used to provide ADR with a low-temperature environment of less than 4 K. A superfluid helium bath was connected to the ADR, via a mechanical heat switch. In the experiment, the CPA salt pill can be pre-cooled to 1.35 K by the superfluid helium bath. A superconductor power supply is used to magnetize and demagnetize the crystal. After applying a 1 T magnetic field, the single-stage ADR can obtain a minimum temperature of 318.5 mK.

Manipulating the insulator–metal transition in strongly correlated materials has attracted a broad range of research activity due to its promising applications in, for example, memories, electrochromic windows and optical modulators1,2. Electric-field-controlled hydrogenation using ionic liquids3–6and solid electrolytes7–9is a useful strategy to obtain the insulator–metal transition with corresponding electron filling, but faces technical challenges for miniaturization due to the complicated device architecture. Here we demonstrate reversible electric-field control of nanoscale hydrogenation into VO2with a tunable insulator–metal transition using a scanning probe. The Pt-coated probe serves as an efficient catalyst to split hydrogen molecules, while the positive-biased voltage accelerates hydrogen ions between the tip and sample surface to facilitate their incorporation, leading to non-volatile transformation from insulating VO2into conducting HxVO2. Remarkably, a negative-biased voltage triggers dehydrogenation to restore the insulating VO2. This work demonstrates a local and reversible electric-field-controlled insulator–metal transition through hydrogen evolution and presents a versatile pathway to exploit multiple functional devices at the nanoscale.

The relationship between trans-stenotic blood flow velocity differences and the cerebral venous pressure gradient (CVPG) in transverse sinus (TS) stenosis (TSS) has not been studied.

Secretory Immunoglobulin A (SIgA) is the most abundant antibody at the mucosal surface. It possesses two additional subunits besides IgA: the joining chain (J-chain) and secretory component (SC). SC is the ectodomain of the polymeric immunoglobulin receptor (pIgR), which functions to transport IgA to the mucosa. How the J-chain and pIgR/SC facilitate the assembly and secretion of SIgA remains incompletely understood. Furthermore, during the infection of Streptococcus pneumoniae, the pneumococcal adhesin SpsA hijacks pIgR/SC and SIgA to gain entry to human cells and evade host defense. How SpsA targets pIgR/SC and SIgA also remains elusive. Here we report a cryo-electron microscopy structure of the Fc region of IgA1 (Fcα) in complex with the J-chain and SC (Fcα-J-SC), which reveals the organization principle of SIgA. We also present a structure of Fcα-J-SC complexed with SpsA, which uncovers the specific interactions between SpsA and human pIgR/SC. These results advance the molecular understanding of SIgA and shed light on S. pneumoniaepathogenesis.

H2production under anaerobic conditions was greatly affected by the C/N ratio of the substrate. Co-fermentation of waste activated sludge (WAS) and agricultural waste was used to modulate the C/N ratio for H2production. In this study, the effects of different C/N ratios, ranging from 6:1 to 55:1, on H2production from the anaerobic digestion of a mixture of WAS and wheat straw were studied. It was observed that the mixture system with a C/N ratio of 45:1 provided optimal conditions for H2production. H2production in the mixture system was 5.2- and 1.2-fold greater than that in the sole sludge (C/N 6:1) and sole straw (C/N 55:1) systems, respectively. Under the optimal C/N ratio, soluble chemical oxygen demand, volatile fatty acids and activities of key enzymes were improved. Firmicutes and Bacteroidetes were the dominant microorganisms in the mixture and sole straw systems that were beneficial to organic matter degradation, utilization, and H2production. Clostridia played an important role in H2production. A balanced C/N ratio favors the co-fermentation process.

Single-phase materials with room temperature (RT) exchange bias (EB) are very important for future applications in spintronic devices, magnetic storage, and sensors. However, such materials are rare because EB normally occurs with ferromagnetic (FM)/antiferromagnetic (AFM) boundaries. In this work, RT EB was realized by breaking the homogeneous structure of long-period Aurivillius oxides through a simple Fe/Ti content modulation. Fantastic intergrowth structures, with different neighboring layer numbers larger than 1, were first observed in this material system with optimized compositions. The intergrowth structure introduces a much larger lattice distortion and probability of Fe–O–Fe interaction, which can largely enhance the EB effect and the EB temperature. Most importantly, RT EB was finally realized in Bi10Fe6+yTi3–yO30+δ(x= 0.2, 0.4) samples with the largest HEof ∼38 Oe measured at 300 K. Significantly, the concurring room temperature multiferroic behavior in such materials may add a new regulating factor for the EB through the application of an electrical field, which is meaningful for future device operations. The findings in this work alleviate the limitation of fabricating Aurivillius oxides with large layer numbers and shed new light on realizing room temperature EB in single-phase materials, with the potential for building future magnetically or electrically controlled spintronic devices.

Background: Orlistat is commonly as a potent and long-lasting specific inhibitor of gastric and pancreatic lipase. Seven potential process-related impurities and degradation products were discovered in orlistat capsule out of which two were novel. However, no analytical methods reported in the literature could separate all the impurities presented in this work. Therefore, it is necessary to develop a simple, rapid and reliable HPLC method to detect potential impurities in orlistat pharmaceutical dosage forms and identify the novel impurities. Methods and Results: The drug was subjected to the stress conditions of oxidative, acid, base, thermal and photolytic degradation as per International Conference on Harmonization (ICH). A gradient reverse phase highperformance liquid chromatographic (RP-HPLC) method with UV spectrophotometric detection was developed for separating the impurities and degradation products in orlistat capsules. Results showed that the main peak and the degradation products were well resolved. Five degradation impurities were characterized rapidly and two novel impurities were found. Liquid chromatography coupled with electrospray ionization, quadrupole-time of flight mass spectrometry (LC-ESIMS/ Q-TOF) was used to identify the novel impurities. After comparing their retention time and mass spectrometric data with that of available standards and references, initial structural confirmation of these impurities were obtained. Based on the spectrometric data and other assistant experiments, the novel impurities were characterized as (2S, 3R, 5S)-5-((formyl- D-leucyl)oxy)-2-hexyl-3-hydroxyhexadecanoic acid and (2S, 3S, 5S)-5-((formyl-D-leucyl)oxy)-2-hexyl-3- hydroxyhexadecanoic acid. The method was validated for specificity, accuracy, precision, linearity, limit of detection, limit of quantification, and robustness according to the present ICH guidelines. Conclusion: A novel, sensitive and selective gradient reverse phase high-performance liquid chromatographic (RPHPLC) method with UV spectrophotometric detection was developed and validated to detect seven impurities out of which two were novel and not reported in earlier literature. The two novel impurities were identified by LC-ESI-MS/QTOF. The proposed HPLC method was suitable for routine analysis of orlistat in pharmaceutical dosage forms and assessed the stability of samples of orlistat.

Realization of ferromagnetism in the two-dimensional (2D) van der Waals (vdW) crystals opens up a vital route to understand the magnetic ordering in the 2D limit and to design novel spintronics. Here, we report enriched layer-number-dependent magnetotransport properties in the vdW ferromagnet Fe5GeTe2. By studying the magnetoresistance and anomalous Hall effect (AHE) in nanoflakes with thicknesses down to monolayer, we demonstrate that while the bulk crystals exhibit soft ferromagnetism with an in-plane magnetic anisotropy, hard ferromagnetism develops upon thinning, and a perpendicular easy-axis anisotropy is realized in bilayer flakes, which is accompanied by a pronounced enhancement of AHE because of extrinsic mechanisms. For the monolayer flakes, the hard ferromagnetism is replaced by spin-glass-like behavior, in accordance with the localization effect in the 2D limit. Our results highlight the thickness-based tunability of the magnetotransport properties in the atomically thin vdW magnets that promises engineering of high-performance spintronic devices.

In order to analyse the self-pressurization of the cryogenic fluid tank more accurately and further understand the law of the cryogenic fluid storage, a new self-pressurization model considering the temperature gradient of the vapour is presented. This model uses one-dimension method to deal with the vapour phase and lumped parameter method to deal with the liquid phase. Another two classical self-pressurization models are used to compare with this model. Based on this model, the comparison between the computation and the experimental results is conducted. The calculated results show that when the tank is in low fill level, the computation is in agreement with the experiment, but in high fill level the difference increases. Experimental results indicate that the new model can properly predict the pressurization curves of the tank.