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Magnetic reconnection occurs ubiquitously in the universe and is often invoked to explain fast energy release and particle acceleration in high-energy astrophysics. The study of relativistic magnetic reconnection in the magnetically dominated regime has surged over the past two decades, revealing the physics of fast magnetic reconnection and nonthermal particle acceleration. Here we review these recent progresses, including the magnetohydrodynamic and collisionless reconnection dynamics as well as particle energization. The insights in astrophysical reconnection strongly connect to the development of magnetic reconnection in other areas, and further communication is greatly desired. We also provide a summary and discussion of key physics processes and frontier problems, toward a better understanding of the roles of magnetic reconnection in high-energy astrophysics. [ABSTRACT FROM AUTHOR]

This study presents the design and implementation of a low-speed intrusion experiment under microgravity, with a strong motivation to support the pre-research of the Chinese asteroid exploration mission. In the experiment apparatus, we reconstructed an effective gravity of 10 - 2 g in a free-falling capsule in the drop tower. The simulant of regolith particles is processed using natural basalt and sorted using layered screens. The irregular shapes of the particles are retained to mimic the realistic regolith. A detailed description of the experimental system components and the full-cycle procedure is first presented, which gives 3.6 s of microgravity time for each trial. Repeatable controlled experiments are performed to characterize the dynamical responses of the simulant particles under centimeter-per second intrusion. The results reveal diverse responses that depend on different variables, and the mechanism of different responses is discussed based on theories of granular mechanics. This experimental study is expected to improve our understanding of the contact mechanics of regolith material, which will facilitate the operation design of future asteroid missions. [ABSTRACT FROM AUTHOR]

Background: Sleep deprivation (SD) is commonplace in modern society and there are large individual differences in the vulnerability to SD. We aim to identify the structural network differences based on diffusion tensor imaging (DTI) that contribute to the individual different vulnerability to SD. Methods: The number of psychomotor vigilance task (PVT) lapses was used to classify 49 healthy subjects on the basis of whether they were vulnerable or resistant to SD. DTI and graph theory approaches were used to investigate the topologic organization differences of the brain structural connectome between SD‐vulnerable and ‐resistant individuals. We measured the level of global efficiency and clustering in rich club and non‐rich club organizations. Results: We demonstrated that participants vulnerable to SD had less global efficiency, network strength, and local efficiency but longer shortest path length compared with participants resistant to SD. Lower efficiency was mainly distributed in the right insula, bilateral thalamus, bilateral frontal, temporal, and temporal lobes. Furthermore, a disrupted subnetwork was observed that consisted of widespread connections. Moreover, the vulnerable group showed significantly decreased strength of the rich club compared with the resistant group. The strength of rich club connectivity was found to be correlated negatively with PVT performance (r = −0.395, p = 0.005). We further tested the reliability of the results. Conclusion: The findings revealed that individual differences in resistance to SD are related to disrupted topologic efficiency connectome pattern, and our study may provide potential connectome‐based biomarkers for the early detection of the vulnerable degree to SD. [ABSTRACT FROM AUTHOR]

Background: Cervical cancer (CC) is a potential clinical application of PD-1/PD-L1 inhibitor. We aimed to study the mechanism of DNA mismatch repair (MMR) system regulating the expression of PD-L1 in CC through DNA methyltransferase (DNMTs). Methods: We collected pathological specimens from 118 cases of CC to analyze the relationship between PD-L1 expression and DNMTs in different MMR states. RNA interference (RNAi) technique was used to simulate the formation of CC cell line with MMR deficiency (dMMR) state, and subcutaneous tumor formation experiment was carried out in nude mice to verify the relationship between PD-L1 expression and DNMTs in MMR state. Results: The PD-L1 positive rate in 118 cases of CC was 58.47%, while the microsatellite instability (MSI) status accounted for 5.93%. There was a significant difference in the expression of PD-L1 between patients within the dMMR and MMR proficient (pMMR) groups (χ2 = 21.405, P < 0.001). Subcutaneous inoculation after infection of Siha cells led to successful tumorigenesis in nude mice, accompanied by a significant increase in the level of PD-L1 expression in the mouse tumors, while the expression level of MLH1 and MSH2 protein decreased significantly. We also found that PD-L1 expression was closely related to the expression of DNMTs. Conclusion: PD-L1 is universal expressed on the surface of CC cells, dMMR status enhances the expression of PD-L1 on the surface of CC cells, dMMR states of CC are related to the demethylation status of the PD-L1 gene promoter region. [ABSTRACT FROM AUTHOR]

The sustainability of biogas production from straws is limited by the collection, transportation, storage, and pretreatment of feedstocks. To address these constraints, this study investigated briquetting as a pretreatment strategy for rice straw (RS) to increase bioenergy generation. The results indicated that briquetted RS yielded 205.4 mL/g VS of methane, which was 11.7% higher compared to that produced by the untreated RS. The economic analysis revealed that the briquetting process had positive effects with a payback time of 3.4 y and an internal rate of return of 23.4%. It also reduced feedstock transportation and storage costs by 42.6%. Adding a NaOH treatment to the briquetting process increased methane production by 26.4% compared to untreated RS. However, the integration of briquetting with NaOH treatment might be an unprofitable method for processing RS. This became apparent when examining the production cost, which stood at 1.13 $/kg biomethane with an internal rate of return of 16.2%, representing an 8.7% increase and a 7.2% decrease, respectively, compared to the mono briquetting method. These results revealed that briquetting as a source pretreatment strategy can improve the productivity of straw biogas plants, thereby advancing the industry towards cleaner production. [Display omitted] • Briquetting, a source pretreatment strategy, improved straw biogas production. • The briquetting strategy integrates the collection and pretreatment of rice straw. • The proposed strategy reduced straw transportation and storage costs by 42.6%. • Adding an NaOH treatment reduced the profitability of a straw biogas plant. [ABSTRACT FROM AUTHOR]

Aims: The brain function impairment induced by sleep deprivation (SD) is temporary and can be fully reversed with sufficient sleep. However, in many cases, long‐duration recovery sleep is not feasible. Thus, this study aimed to investigate whether a short nap after SD is sufficient to restore brain function. Methods: The data of 38 subjects, including resting state functional magnetic resonance imaging data collected at three timepoints (before SD, after 30 h of SD, and after a short nap following SD) and psychomotor vigilance task (PVT) data, were collected. Dynamic functional connectivity (DFC) analysis was used to evaluate changes in brain states among three timepoints, and four DFC states were distinguished across the three timepoints. Results: Before SD, state 2 (a resting‐like FC matrix) was dominant (48.26%). However, after 30 h SD, the proportion of state 2 dramatically decreased, and state 3 (still resting‐like, but FCs were weakened) became dominant (40.92%). The increased proportion of state 3 positively correlated with a larger PVT "lapse" time. After a nap, the proportions of states 2 and 3 significantly increased and decreased, respectively, and the change in proportion of state 2 negatively correlated with the change in PVT "lapse" time. Conclusions: Taken together, the results indicated that, after a nap, the cognitive function impairment caused by SD may be reversed to some extent. Additionally, DFC differed among timepoints, which was also associated with the extent of cognitive function impairment after SD (state 3) and the extent of recovery therefrom after a nap (state 2). [ABSTRACT FROM AUTHOR]

Background: Diabetic cardiomyopathy (DCM) is a serious complication in patients with type 1 diabetes mellitus (T1DM), which still lacks adequate therapy. Irisin, a cleavage peptide off fibronectin type III domain-containing 5, has been shown to preserve cardiac function in cardiac ischemia–reperfusion injury. Whether or not irisin plays a cardioprotective role in DCM is not known. Methods and results: T1DM was induced by multiple low-dose intraperitoneal injections of streptozotocin (STZ). Our current study showed that irisin expression/level was lower in the heart and serum of mice with STZ-induced TIDM. Irisin supplementation by intraperitoneal injection improved the impaired cardiac function in mice with DCM, which was ascribed to the inhibition of ferroptosis, because the increased ferroptosis, associated with increased cardiac malondialdehyde (MDA), decreased reduced glutathione (GSH) and protein expressions of solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4), was ameliorated by irisin. In the presence of erastin, a ferroptosis inducer, the irisin-mediated protective effects were blocked. Mechanistically, irisin treatment increased Sirtuin 1 (SIRT1) and decreased p53 K382 acetylation, which decreased p53 protein expression by increasing its degradation, consequently upregulated SLC7A11 and GPX4 expressions. Thus, irisin-mediated reduction in p53 decreases ferroptosis and protects cardiomyocytes against injury due to high glucose. Conclusion: This study demonstrated that irisin could improve cardiac function by suppressing ferroptosis in T1DM via the SIRT1-p53-SLC7A11/GPX4 pathway. Irisin may be a therapeutic approach in the management of T1DM-induced cardiomyopathy. [ABSTRACT FROM AUTHOR]

Membrane separation plays a crucial role in the current increasingly complex energy environment. Membranes prepared by metal–organic framework (MOF) materials usually possess unique advantages in common, such as uniform pore size, ultra‐high porosity, enhanced selectivity and throughput, and excellent adsorption property, which have been contributed to the separation fields. In this comprehensive review, we summarize various designs and synthesized strategies of free‐standing MOF and composite MOF‐based membranes for water treatment. Special emphases are given not only on the effects of MOF on membrane performance, removal efficiencies, and elimination mechanisms, but also on the importance of MOF‐based membranes for the applications of oily and micro‐pollutant removal, adsorption, separation, and catalysis. The challenges and opportunities in the future for the industrial implementation of MOF‐based membranes are also discussed. [ABSTRACT FROM AUTHOR]

The development of renewable, hydrophobic, and biodegradable intelligent packaging materials as an alternative to petroleum-based plastic products has become a new research focus in recent years, but remains a challenge. Herein, regenerated cellulose/curcumin composite films were fabricated by dispersing hydrophobic curcumin uniformly in a hydrophilic cellulose matrix using an aqueous alkali/urea solvent based on the pH-driven principle of curcumin. In addition, a unilateral hydrophobic modification was carried out using chemical vapor deposition of methyltrichlorosilane to obtain Janus structure. The composite films exhibited high transparency in the visible light spectrum, excellent antioxidation, thermal stability, mechanical strength, gas barrier properties, and antibacterial activity. Furthermore, the films demonstrated the capability to lower the overall levels of volatile basic nitrogen in stored fish. The color of the films shifted from a pale yellow to a reddish-brown over time during storage. The composite films can be completely degraded after approximately 98 days in soil with an average environmental temperature of 29 °C. This work provided a facile strategy to prepare biodegradable cellulose/curcumin films with Janus structure as packaging materials which could preserve the freshness of food products while offering visual monitor of their freshness in real-time. [Display omitted] [ABSTRACT FROM AUTHOR]

Interspecies blastocyst complementation (IBC) provides a unique platform to study development and holds the potential to overcome worldwide organ shortages. Despite recent successes, brain tissue has not been achieved through IBC. Here, we developed an optimized IBC strategy based on C-CRISPR, which facilitated rapid screening of candidate genes and identified that Hesx1 deficiency supported the generation of rat forebrain tissue in mice via IBC. Xenogeneic rat forebrain tissues in adult mice were structurally and functionally intact. Cross-species comparative analyses revealed that rat forebrain tissues developed at the same pace as the mouse host but maintained rat-like transcriptome profiles. The chimeric rate of rat cells gradually decreased as development progressed, suggesting xenogeneic barriers during mid-to-late pre-natal development. Interspecies forebrain complementation opens the door for studying evolutionarily conserved and divergent mechanisms underlying brain development and cognitive function. The C-CRISPR-based IBC strategy holds great potential to broaden the study and application of interspecies organogenesis. [Display omitted] • C-CRISPR enables quick candidate gene screening aiding blastocyst complementation • Mouse and rat ESCs can both complement Hesx1 −/− forebrain agenesis in mice • Reconstituted rat forebrains in mice exhibit normal structure and function • Rat forebrains in mice develop at mouse rates with rat-specific gene expression An optimized screening platform streamlined the identification of mutations that supported the generation of rat forebrain tissue in mice via interspecies blastocyst complementation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Calculation-guided structure optimization was used to redesign Lns/Ans separation ligand. • Phenanthroline diamide ligands were prepared to reduce the rotation barriers for coordination. • Record high separation factors of SF Eu(III)/Am(III) were reported in n -octanol in high acidity. • Well-balanced extraction/stripping/recycling were demonstrated. Liquid-liquid extraction is the most wildly adopted industrial Lns/Ans separation approach which takes advantages of the subtle atomic size differences for Lns and Ans. Preorganized ligand architecture with coordination configuration locking strategy has been proven to be very efficient to enhance the separation factors by size exclusive effect from the preset ligand cavity while drawbacks such as sophisticated ligand synthesis, unbalanced extraction/stripping performances and limited solubility in environmental benign solvents prevent the economic practicability. In the current contribution, calculation-guided ligand structure optimization was utilized to optimize the hard/soft tetradentate phenanthroline diamide ligands. Reducing the number of alkyl chains around the binding sites from amide to imide led to less rotation energy barriers, eventually boosted both metal distributions and separation factors. Additionally, the formation of hydrogen bonds in the imine ligands enhanced their solubility in industrial-friendly solvent, such as n -octanol, leading to superior extraction performances. Finally, balanced extraction, stripping and recycling of the reported ligands were demonstrated to unravel the potential to be integrated into current industrial plants. The ligand design philosophy as discussed in this work could inspire the searching for new environment-friendly high-performance lipophilic ligand to close the current nuclear fuel cycle. [ABSTRACT FROM AUTHOR]

An in situ reversible assembly strategy is demonstrated for the fabrication of p-n heterojunctions in BiOI/Bi 5 O 7 I composites. This approach allows for the generation of ample interfacial interactions and built-in electric field, resulting in a strong driving force for effective charge separation. These advantages drastically enhance the photocatalytic activity of BiOI/Bi 5 O 7 I composites towards efficient CO 2 reduction and pollutants degradation using visible light. [Display omitted] • In-situ reversible assembly strategy to fabricate BiOI/Bi 5 O 7 I p–n heterojunctions. • BiOI/Bi 5 O 7 I p–n heterojunctions provide ample interfacial interaction. • These advantages enable efficient visible-light photocatalysis for CO 2 reduction. • Theoretical and experimental studies reveal insights on interfacial charge transfer. Constructing efficient p-n heterojunctions holds great potential in the realm of photocatalysis for promoting the sustainable development of the environment and energy industries. However, traditional p-n heterojunctions suffer from limited interfacial interaction which severely restricts the effectiveness of the built-in electric field in boosting charge separation. Herein, we present an in situ reversible assembly approach to fabricate functional p-n junction in BiOI/Bi 5 O 7 I composites at room temperature. By controlling the reaction time or the amount of KI precursor added, we attain the as-designed BiOI@Bi 5 O 7 I and Bi 5 O 7 I@BiOI heterojunctions with large specific surface area and ample interfacial electric field. Subsequent application of the optimized heterojunction material as visible-light photocatalyst achieves efficient photoreduction of CO 2 reactant into CO product (0.46 μmol g−1h−1), even without using any sacrificial agent in the gas–solid reaction system. This catalytic performance is notably ∼ 6.6 times and 15.3 times higher than that of standalone BiOI and Bi 5 O 7 I materials, respectively. In situ XPS, in situ Kelvin probe force microscopy, and theoretical calculations reveal that the built-in electric field induces directional charge transfer to greatly boosts the efficiency of separating photogenerated electron-hole pairs at the interface of BiOI and Bi 5 O 7 I. This study provides valuable insights for the rational design and straightforward fabrication of next-generation, integrated heterostructured photoelectronic materials for efficient energy, environmental, and chemical applications. [ABSTRACT FROM AUTHOR]

Magnetic solid-phase extraction (MSPE) was developed based on a well-designed Fe 3 O 4 -NH 2 @g-C 3 N 4 nanocomposite as sorbent for a mixture of six benzophenones (BPs) in environmental water samples. The composite fabricated via in-situ self-assembled g-C 3 N 4 shell with homogeneous polymerization of cyanuric chloride and cyanuric acid on Fe 3 O 4 -NH 2 core. While high adsorption capacity was derived from g-C 3 N 4 via hydrophobic, π-π and hydrogen bonding interactions to the targets, the fast magnetic separation was realized with Fe 3 O 4 core for less solvent consumption. In combination with LC-MS/MS, the Fe 3 O 4 -NH 2 @g-C 3 N 4 sorbent minimized the interfering components, reduced the matrix effects, and provided the enrichment factors of 121–150 for six BPs with relative standard deviations ≤ 9.7% even after 20 times extraction-desorption cycles. The present method gave the detection limits of 0.3–2.5 ng/L for six BPs with the linear ranges of 1.0–2000 ng/L, and the recoveries of 84.6%−104% in sea water and 86.2%−107% in lake water samples. Thus, the Fe 3 O 4 -NH 2 @g-C 3 N 4 -based MSPE coupled with LC-MS/MS method provided a convenient, efficient, and reliable alternative to monitor trace BPs in environmental water samples. [Display omitted] • Core-shell Fe 3 O 4 -NH 2 @g-C 3 N 4 was prepared via in-situ self-assembled growth. • The sorbent was applied for simple and effective MSPE of BPs in environmental water. • The method offered EFs of 121–150 and 20 cycles of extraction with RSD ≤ 9.7%. [ABSTRACT FROM AUTHOR]