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Antiferromagnetic spintronics1,2 shows great potential for high-density and ultrafast information devices. Magnetic tunnel junctions (MTJs), a key spintronic memory component that are typically formed from ferromagnetic materials, have seen rapid developments very recently using antiferromagnetic materials3,4. Here we demonstrate a twisting strategy for constructing all-antiferromagnetic tunnel junctions down to the atomic limit. By twisting two bilayers of CrSBr, a 2D antiferromagnet (AFM), a more than 700% nonvolatile tunnelling magnetoresistance (TMR) ratio is shown at zero field (ZF) with the entire twisted stack acting as the tunnel barrier. This is determined by twisting two CrSBr monolayers for which the TMR is shown to be derived from accumulative coherent tunnelling across the individual CrSBr monolayers. The dependence of the TMR on the twist angle is calculated from the electron-parallel momentum-dependent decay across the twisted monolayers. This is in excellent agreement with our experiments that consider twist angles that vary from 0° to 90°. Moreover, we also find that the temperature dependence of the TMR is, surprisingly, much weaker for the twisted as compared with the untwisted junctions, making the twisted junctions even more attractive for applications. Our work shows that it is possible to push nonvolatile magnetic information storage to the atomically thin limit.By twisting two bilayers of CrSBr, which is a 2D antiferromagnet, a >700% nonvolatile tunnelling magnetoresistance at zero field is shown, demonstrating a new strategy for constructing all-antiferromagnetic tunnel junctions down to the atomic limit. [ABSTRACT FROM AUTHOR]

Photo-Fenton catalysis plays an important role in the degradation of organic pollutants in environmental sewage. In this paper, magnetic 0D/1D ZnFe2O4/ZnCO3 rod-like nanocomposites were fabricated by a simple one-pot solvothermal method, and then the produced magnetic 0D/1D ZnFe2O4/ZnO rod-like nanocomposites were formed via calcination at high temperature. The obtained 0D/1D ZnFe2O4/ZnCO3 has been fully investigated by x-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, and vibrating sample magnetometry. Furthermore, the photocatalytic Fenton reaction of these two catalysts has been preliminarily evaluated for the degradation performance of organic dyes and antibiotics in wastewater. The results showed that, under visible-light irradiation, the ZnFe2O4/ZnCO3 composite material and its product, ZnFe2O4/ZnO, after high-temperature firing can achieve more than 90% photo-Fenton catalytic degradation of Rhodamine B (RhB) and tetracycline (TC) within 30 min, superior to that of ZnFe2O4, ZnCO3 , and ZnO monomers due to their larger specific surface area and more active sites. The magnetization saturation values of ZnFe2O4/ZnCO3-2 and ZnFe2O4/ZnO-2 were, respectively, around 34.20 emu/g and 15.00 emu/g, indicating that both have good magnetic recovery properties. After five cycles of experiments, the photo-Fenton catalytic properties of ZnFe2O4/ZnCO3-2 and ZnFe2O4/ZnO-2 on TC decreased slightly within 30 min, but the Fenton catalytic properties of RhB still maintained more than 98%, indicating that both have good magnetic recovery properties and strong structural stability. A possible photo-Fenton catalytic mechanism has been proposed based on free radical identification, electrochemical impedance spectra, photocurrent curves, and a Mott–Schottky diagram. This study provided two catalysts with excellent performance for the photo-Fenton catalytic degradation of pollutants in water. [ABSTRACT FROM AUTHOR]

The COVID-19 outbreak encouraged the global development of efficient prevention, diagnosis, and treatment while posing a major threat to the global economy and public health. It is discovered that due to the benefits of nanomaterials, including their ease of preparation, low cost, and ease of modification, there is a new possibility to create tactics against SARS-CoV-2. Studies on the economic viability, long-term safety, biocompatibility, and environmental effects of nanomaterials are still scarce, nevertheless. Currently, the primary methods for combating the SARS-CoV-2 virus are the creation of potent disinfectants, quick and precise diagnostic instruments, and nanovaccines. In order to give useful data reference for the development of nanomaterials against SARS-CoV-2 virus, this review first provides a brief introduction to the structure and infection mode of the SARS-CoV-2 virus. It next assesses the use of nanomaterials themselves. In order to establish a comprehensive cooperative battle against SARS-CoV-2 virus, it concludes by focusing on the application of nanomaterials for the prevention, diagnosis, and treatment of SARS-CoV-2 virus as well as their combined application with existing technologies. [ABSTRACT FROM AUTHOR]

Purpose: The previous studies have suggested that serum homocysteine (Hcy) and vitamin B levels are potentially related to autism spectrum disorder (ASD). However, the causality between their concentrations and ASD risk remains unclear. To elucidate this genetic association, we used a Mendelian randomization (MR) design. Methods: For this MR analysis, 47 single-nucleotide polymorphisms (SNPs)—13 related to Hcy, 13 to folate, 14 to vitamin B6, and 7 to vitamin B12—were obtained from a large-scale Genome-Wide Association Studies (GWAS) database and employed as instrumental variables (IVs). Our study used three approaches to calculate the MR estimates, including inverse-variance weighted (IVW) method, MR-Egger method, and weighted median (WM) method. Among these, the IVW method served as our primary MR method. False discovery rate (FDR) was implemented to correct for multiple comparisons. We also performed a series of sensitivity analyses, including Cochran's Q test, MR-Egger's intercept, MR-PRESSO, leave-one-out analysis, and the funnel plot. Results: Univariable Mendelian randomization (UVMR) analysis revealed a statistical association between serum vitamin B12 levels and ASD risk (OR = 1.68, 95% CI 1.12–2.52, P = 0.01) using the IVW method. However, neither the WM method (OR = 1.57, 95% CI 0.93–2.66, P = 0.09) nor the MR-Egger method (OR = 2.33, 95% CI 0.48–11.19, P = 0.34) was significantly association with higher levels of serum vitamin B12 and ASD risk. Additionally, we found no evidence of causal relationships between serum levels of vitamin B6, folate, Hcy, and ASD risk. After correcting for the FDR, the causality between serum vitamin B12 levels and ASD risk remained significant (q value = 0.0270). Multivariate Mendelian randomization (MVMR) analysis indicated an independent association between elevated serum vitamin B12 levels and the risk of ASD (OR = 1.74, 95% CI 1.03–2.95, P = 0.03) using the IVW method, but this finding was inconsistent when using the WM method (OR = 1.73, 95% CI 0.89–3.36, P = 0.11) and MR-Egger method (OR = 1.60, 95% CI 0.95–2.71, P = 0.08). Furthermore, no causal associations were observed for serum levels of vitamin B6 and folate in MVMR analysis. Sensitivity analyses confirmed that these results were reliable. Conclusion: Our study indicated that elevated serum vitamin B12 levels might increase the risk of ASD. The potential implications of our results for ASD risk warrant validation in randomized clinical trials. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) is a severe medical condition with lasting effects. The efficacy of numerous clinical treatments is hampered by the intricate pathophysiological mechanism of SCI. Fibroblast growth factor 18 (FGF-18) has been found to exert neuroprotective effects after brain ischaemia, but its effect after SCI has not been well explored. The aim of the present study was to explore the therapeutic effect of FGF-18 on SCI and the related mechanism. In the present study, a mouse model of SCI was used, and the results showed that FGF-18 may significantly affect functional recovery. The present findings demonstrated that FGF-18 directly promoted functional recovery by increasing autophagy and decreasing pyroptosis. In addition, FGF-18 increased autophagy, and the well-known autophagy inhibitor 3-methyladenine (3MA) reversed the therapeutic benefits of FGF-18 after SCI, suggesting that autophagy mediates the therapeutic effects of FGF-18 on SCI. A mechanistic study revealed that after stimulation of the protein kinase B (AKT)-transient receptor potential mucolipin 1 (TRPML1)-calcineurin signalling pathway, the FGF-18-induced increase in autophagy was mediated by the dephosphorylation and nuclear translocation of transcription factor E3 (TFE3). Together, these findings indicated that FGF-18 is a robust autophagy modulator capable of accelerating functional recovery after SCI, suggesting that it may be a promising treatment for SCI in the clinic. [ABSTRACT FROM AUTHOR]

CNS (central nervous system) trauma, which is classified as SCI (spinal cord injury) and TBI (traumatic brain injury), is gradually becoming a major cause of accidental death and disability worldwide. Many previous studies have verified that the pathophysiological mechanism underlying cell death and the subsequent neuroinflammation caused by cell death are pivotal factors in the progression of CNS trauma. Simultaneously, EVs (extracellular vesicles), membrane-enclosed particles produced by almost all cell types, have been proven to mediate cell-to-cell communication, and cell death involves complex interactions among molecules. EVs have also been proven to be effective carriers of loaded bioactive components to areas of CNS trauma. Therefore, EVs are promising therapeutic targets to cure CNS trauma. However, the link between EVs and various types of cell death in the context of CNS trauma remains unknown. Therefore, in this review, we summarize the mechanism underlying EV effects, the relationship between EVs and cell death and the pathophysiology underlying EV effects on the CNS trauma based on information in published papers. In addition, we discuss the prospects of applying EVs to the CNS as feasible therapeutic strategies for CNS trauma in the future. [ABSTRACT FROM AUTHOR]

Controlling the crystallization of Metal–Organic Frameworks (MOFs) at the nanoscale is currently challenging, and this hinders their utilization for multiple applications including photo(electro)chemistry and sensors. In this work, we show a synthetic protocol that enables the preparation of highly homogeneous Cu2O@MOF nanowires standing on a conductive support with extensive control over the crystallization of the MOF nanoparticles at the surface of the Cu2O nanowires. Cu2O nanowires were first prepared via templated electrodeposition, and then partially converted into the well-known Cu-MOF HKUST-1 by pulsed electrochemical oxidation. We show that the use of PVP as a capping agent during the electrochemical oxidation of Cu2O into HKUST-1 provides control over the growth of the MOF nanocrystals on the surface of the Cu2O nanowires, and that the size of the MOF crystals obtained can be tuned by changing the concentration of PVP dissolved in the electrolyte. In addition, we propose the use of benzoic acid as an alternative to achieve control over the size of the obtained MOF nanocrystals when the use of a capping agent should be avoided. [ABSTRACT FROM AUTHOR]

Pollution from uranium tailings ponds poses a severe threat to aquatic ecosystems. However, its effects on litterfall decomposition in aquatic environments are uncertain. This study was conducted to investigate the effects of different species (Macleaya cordata and Typha orientalis Presl), sources (inside and outside the tailings pond), sites (above and below ground), initial biomass (1, 2, and 4 g) and initial ambient uranium concentrations (0, 1, and 3 mg/L) on the decomposition of uranium-containing litterfall. The study found that the above-mentioned indicators (litterfall self-characteristics and environmental factors) affect the decomposition of uranium-containing litterfall. The decomposition rate of litterfall in the water environment is related to the plant species, sites, and initial biomass, mainly due to the differences in the content of plant structural materials (cellulose, hemicellulose, and lignin). Uranium concentration is also an important factor affecting the decomposition of litterfall. A high concentration of uranium may affect the activities of microorganisms and thus inhibit the decomposition of litterfall, while a low concentration of uranium has the effect of accelerating the decomposition. In addition, the uranium content in M. cordata increased significantly after decomposition, but T. orientalis was the opposite, and both metal pools decreased significantly. At the same time, the underground parts of the two plants released more uranium than the aboveground parts. In conclusion, this study provides new insights and a scientific basis for the risks posed by the uranium mining industry. [ABSTRACT FROM AUTHOR]

We aimed to explore whether an elevated blood lead level (BLL) is associated with visceral adipose dysfunction in patients with type 2 diabetes mellitus (T2DM). Four thousand one hundred and fourteen diabetic participants were enrolled from seven communities in Shanghai in 2018 in the cross-sectional METAL study. BLL was measured by graphite furnace atomic absorption spectrometry. Visceral adiposity index (VAI) and lipid accumulation product (LAP)were calculated by simple anthropometric and biochemical parameters. We found that medians (IQR) of BLL were 26.0 μg/L (18.0–37.0) for men and 25.0 μg/L (18.0–35.0) for women, respectively. In men, each doubling of BLL was associated with a 2.0% higher VAI (95% CI, 0.6 to 3.5%) and 1.8% higher LAP (95% CI, 0.2 to 3.3%) after full adjustment. Using the lowest BLL quartile as the referent group, significant positive trends were observed for BLL with VAI and LAP. In women, each doubling of BLL was associated with a 1.9% higher LAP (95% CI, 0.6 to 3.1%). Additionally, there was a marginally significant positive association between BLL and VAI, either using log2-transformed concentrations as continuous variables or categorized in quartiles. In conclusion, lead exposure is associated with visceral adipose dysfunction in patients with T2DM. Further prospective studies are warranted to confirm our findings. [ABSTRACT FROM AUTHOR]

Acid rain is often formed in southwestern China. Red-bed landslides often occur and cause major social and economic losses. The shear-slip process of red-bed landslides is affected by the creep characteristics of the weak interlayers in the rock mass. Samples of red-bed soft rock with weak interlayers of mudstone in Lufeng County of the Central Yunnan Water Diversion Project were tested in shear-creep tests in an acid environment. Combining with the functional relationship between the viscoelastic modulus and the acidic environment change, a stress-acidity-strain–time model is established based on the Burgers model. The results show that the long-term strength of the red-bed soft-rock weak interlayer in a mudstone gradually decreases with the increase of acidity. The viscoelastic modulus is linearly related to acidity. Compared with the traditional Burgers model, the improved Burgers model taking into account the effect of the acidic environment provides improved accuracy in describing the shear-creep behavior of the red-bed soft-rock weak interlayers. [ABSTRACT FROM AUTHOR]

Transplantation of oligodendrocyte progenitor cell (OPC) at the injury site is being developed as a potential therapeutic strategy for promoting remyelination and locomotor function recovery after spinal cord injury (SCI). To this end, the development of expandable and functional human OPCs is crucial for testing their efficacy in SCI. In mice and rats, the endocannabinoid signaling system is crucial for the survival, differentiation, and maturation of OPCs. Similar studies in humans are lacking currently. Endocannabinoids and exogenous cannabinoids exert their effects mainly via cannabinoid receptors (CB1R and CB2R). We demonstrated that these receptors were differentially expressed in iPSC-derived human NSCs and OPCs, and they could be activated by WIN55212-2 (WIN), a potent CB1R/CB2R agonist to upregulate the endocannabinoid signaling during glial induction. WIN primed NSCs generated more OLIG2 + glial progenitors and migratory PDGFRα + OPC in a CB1/CB2 dependent manner compared to unprimed NSCs. Furthermore, WIN-induced OPCs (WIN-OPCs) robustly differentiated into functional oligodendrocytes and myelinate in vitro and in vivo in a mouse spinal cord injury model. RNA-Seq revealed that WIN upregulated the biological process of positive regulation of oligodendrocyte differentiation. Mechanistically, WIN could act as a partial smoothed (SMO) inhibitor or activate CB1/CB2 to form heteromeric complexes with SMO leading to the inhibition of GLI1 in the Sonic hedgehog pathway. The partial and temporal inhibition of GLI1 during glial induction is shown to promote OPCs that differentiate faster than control's. Thus, CB1R/CB2R activation results in more efficient generation of OPCs that can mature and efficiently myelinate. [ABSTRACT FROM AUTHOR]

The cyclic load generated by the blasting vibration in the mining process has a significant degrading effect on the slope rock mass. To clarify the cumulative damage evolution of the microcrystalline limestone under the cyclic blasting load, the microcrystalline limestone in the Zhujiapo mining area in Sichuan Province is used as an example. The research object carried out a triaxial compression test of microcrystalline limestone under a fixed equivalent blasting load. The research results show that: (1) under the same confining pressure, the peak strength and residual strength of the sample are negatively correlated with the number of blasting, and the average correlation indexes are 0.947 and 0.976, respectively; (2) the longitudinal wave velocity of the sample shows "S" with the increase of the number of blasting; the changing trend of the shape reduction; (3) according to the strain equivalent theory and the damage variable defined by the longitudinal wave velocity, an improved nonlinear cumulative damage evolution model based on the number of blasts is established. The research results are hoped to provide a reference for the evaluation of the cumulative damage effect of similar limestone slopes. [ABSTRACT FROM AUTHOR]

Sulfur (S) is an essential macronutrient required by plants. Plants absorb and transport S through sulfate transporters (SULTRs). In this study, we cloned 8 SULTR genes (CsSULTR1;1/1;2/2;1/3;1/3;2/3;3/3;5/4;1) from tea plant (Camellia sinensis), all of which contain a typical sulfate transporter and antisigma factor antagonist (STAS) conserved domain. Phylogenetic tree analysis further divided the CsSULTRs into four main groups. Many cis-acting elements related to hormones and environmental stresses were found within the promoter sequence of CsSULTRs. Subcellular localization results showed that CsSULTR4;1 localized in the vacuolar membrane and that other CsSULTRs localized to the cellular membrane. The tissue-specific expression of the 8 CsSULTR genes showed different expression patterns during the active growing period and dormancy period. In particular, the expression of CsSULTR1;1 was highest in the roots, but that of CsSULTR1;2 was lowest in the dormancy period. The expression of CsSULTR1;1/1;2/2;1/3;2 was stimulated under different concentrations of selenium (Se) and S; moreover, CsSULTR1;2/2;1/3;3/3;5 was upregulated in response to different valences of Se. [ABSTRACT FROM AUTHOR]

Cardiovascular disease (CVD) results in more than half of the mortality and the majority of morbidity in patients with type 2 diabetes. We aim to evaluate the associations of urinary concentrations of phthalate metabolites with CVD in diabetic patients and explore whether CVD risk factors mediate or interact with these associations. A total of 675 type 2 diabetic participants were enrolled from Shanghai, China, in 2018. CVD was defined as a self-reported diagnosis by a physician including coronary heart disease, myocardial infarction, or stroke; it was further reconfirmed in the records from the registration platform. Ten phthalate metabolites were measured in urine. We found positive associations were found among the level of monoethyl phthalate and monoisobutyl phthalate and CVD (OR 1.138, 95% CI 1.032, 1.254; OR 1.369, 95% CI 1.049, 1.786, respectively). Monoisobutyl phthalate and monobenzyl phthalate were marginally and positively associated with carotid intima-media thickness and common carotid artery diameter, respectively. None of the CVD risk factors, including HOMA-IR, body mass index, lipid profile, or blood pressure, significantly mediated the association between the metabolites and CVD. The conditional indirect effect on CVD was significantly stronger for current smoking and dyslipidemia for monoethyl phthalate and for no statin usage and men for monoisobutyl phthalate. In conclusion, phthalate exposure was positively associated with CVD in Chinese with type 2 diabetes. Type 2 diabetic men who are currently smoking, have an uncontrolled lipid profile, and are not using statins might be more susceptible to CVD when exposed to phthalates. [ABSTRACT FROM AUTHOR]

The study of the time-dependent deformation behavior of soft rock under water–rock interaction is of great significance to reveal slope creep deformation behavior. In this study, the saturation-loss cycle's triaxial creep test was performed, and the creep deformation, creep rate, and long-term strength of silty mudstone were analyzed. A two-step improved modeling method was also proposed. Firstly, by introducing fractional Abel viscous pot and aging factor, a one-dimensional creep constitutive model was established based on the Burgers model. And then the three-dimensional creep damage constitutive was derived through Laplace transform. Finally, the Levenberg–Marquardt (L–M) algorithm method was used to identify the creep curve and calibrate the model parameters. The new constitutive model could reflect the soft rock's creep characteristics during saturation-loss cycle. [ABSTRACT FROM AUTHOR]

We report the effect of chemical pressure on the ferromagnetic ordering of the recently reported n-type diluted magnetic semiconductor Ba(Zn 1 - x Co x ) 2 As 2 which has a maximum T C ∼ 45 K. Doping Sb into As-site and Sr into Ba-site induces negative and positive chemical pressure, respectively. While conserving the tetragonal crystal structure and n-type carriers, the unit cell volume shrink by ∼ 0.3 % with 15 % Sr doping, but drastically increase the ferromagnetic transition temperature by 18 % to 53 K. Our experiment unequivocally demonstrate that the parameters of Zn(Co)As 4 tetrahedra play a vital role in the formation of ferromagnetic ordering in the Ba(Zn,Co) 2 As 2 DMS. [ABSTRACT FROM AUTHOR]

Tea plant (Camellia sinensis L.) is capable of accumulating a large amount of fluorine (F) in leaves without showing toxicity symptoms and thus offers a good model for exploring F tolerance mechanisms. Here, gas chromatography time-of-flight mass spectrometry (GC-TOF–MS) was used to investigate metabolic changes in leaves of tea seedlings under control (0 mM), low F (0.2 mM) and high F (0.8 mM) conditions. Differentially changed metabolites such as galacturonic acid, lactose, fructose, malic acid, alanine were identified by the comparison among the three F treatment groups. A pathway map depicted based on the KEGG database reflected the involvement of pectin biosynthesis metabolism in F stress response. The gene expression and enzyme activity of key enzymes involved in pectin biosynthesis pathway and the content of pectic polysaccharides were increased by exogenous F treatments, indicating the promotion effect of F on the pectin biosynthesis. Pectin was also immunochemically stained in vivo using monoclonal antibody (2F4), which confirmed the increment. The increased pectin might contribute to combining the exogenous F in tea leaves. This research provided some novel insights into further research on F detoxification of plants. [ABSTRACT FROM AUTHOR]

The as-cast 40CrNiMo alloy steel with uniform microstructure is obtained through vacuum casting by using metal mold. The hot deformation behavior of as-cast 40CrNiMo alloy steel is investigated by isothermal compression tests. The Arrhenius constitutive model and processing maps of as-cast 40CrNiMo alloy steel are constructed. The results indicate that the true stress–strain curves present typical dynamic recovery type under low deformation temperature and high strain rate. With the increases in deformation temperature or the decreases in strain rate, the true stress–strain curves gradually transform to dynamic recrystallization type. Through the analysis of processing maps and microstructures, it can be found that the area of plastic instability increases with the increase in the strain and gradually expands to the region of high deformation temperature and low strain rate. The deformation temperature range of 850-1050 °C and strain rate range of 0.001-0.01 s−1 are recommended as the reasonable hot-working process conditions. Results of this research can provide references for the selection of process parameters in casting–forging combination forming of 40CrNiMo alloy steel. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the present study is to identify independent risk factors for the occurrence of cement leakage (CL) during percutaneous vertebroplasty (PVP) for four different leakage types in treating osteoporotic vertebral compression fractures (OVCFs).Methods: We retrospectively reviewed 292 patients who underwent PVP for single-level OVCF from January 2009 to March 2011. The influences of several potential risk factors that might affect the occurrence of CL were assessed using univariate and multivariate analyses. Cement leakage was evaluated by computed tomography and classified into four different types: through the basivertebral vein (B-type), the segmental vein (S-type), a cortical defect (C-type), and intradiscal leakage (D-type).Results: Cement leakage was found in 227 of the 292 treated vertebrae. None of the parameters showed a statistically significant effect by univariate analysis. However, multivariate analysis showed that cement viscosity was an independent risk factor in B-type CL, fracture severity and fracture type were in S-type CL, fracture severity and presence of cleft on MRI were in C-type CL, and fracture severity, cortical disruption on MRI, presence of cleft on MRI and cement viscosity were in D-type CL.Conclusion: Each different vertebral fracture pattern has its own risk factors for CL. Identification of the above predicting factors for CL preoperatively might be helpful for more rigorous and strict patient selection criteria for the appropriate candidates for PVP. [ABSTRACT FROM AUTHOR]

Reports on the isolation of reovirus from throat swabs of severe acute respiratory syndrome (SARS) patients in Beijing, China. Inclusion in the study of the first SARS case in Beijing and her mother; Characteristic features of reovirus; Serological responses to the reovirus; Finding in animal experiments that the inoculation of the reovirus in mice caused death with atypical pneumonia.