First-Principles Simulation and Materials Screening for Spin-Orbit Torque in 2D van der Waals Heterostructures.

Recent advancements in spin-orbit torque (SOT) technology in two-dimensional van der Waals (2D vdW) materials have not only pushed spintronic devices to their atomic limits but have also unveiled unconventional torques and novel spin-switching mechanisms. The vast diversity of SOT observed in numerous 2D vdW materials necessitates a screening strategy to identify optimal materials for torque device performance. However, such a strategy has yet to be established. To address this critical issue, a combination of density functional theory and non-equilibrium Green's function is employed to calculate the SOT in various 2D vdW bilayer heterostructures. This leads to the discovery of three high SOT systems: WTe2/CrSe2, MoTe2/VS2, and NbSe2/CrSe2. Furthermore, a figure of merit that allows for rapid and efficient estimation of SOT is proposed, enabling high-throughput screening of optimal materials and devices for SOT applications in the future.

Reduced nitrite accumulation at the primary nitrite maximum in the cyclonic eddies in the western North Pacific subtropical gyre.

Nitrite, an intermediate product of the oxidation of ammonia to nitrate (nitrification), accumulates in upper oceans, forming the primary nitrite maximum (PNM). Nitrite concentrations in the PNM are relatively low in the western North Pacific subtropical gyre (wNPSG), where eddies are frequent and intense. To explain these low nitrite concentrations, we investigated nitrification in cyclonic eddies in the wNPSG. We detected relatively low half-saturation constants (i.e., high substrate affinities) for ammonia and nitrite oxidation at 150 to 200 meter water depth. Eddy-induced displacement of high-affinity nitrifiers and increased substrate supply enhanced ammonia and nitrite oxidation, depleting ambient substrate concentrations in the euphotic zone. Nitrite oxidation is more strongly enhanced by the cyclonic eddies than ammonia oxidation, reducing concentrations and accelerating the turnover of nitrite in the PNM. These findings demonstrate a spatial decoupling of the two steps of nitrification in response to mesoscale processes and provide insights into physical-ecological controls on the PNM.

Bioenhanced degradation of toluene by layer-by-layer self-assembled silica-based bio-microcapsules.

In this study, micron-sized monodisperse SiO2 microspheres were used as sacrificial templates, and chitosan/polylactic acid (CTS/PLA) bio-microcapsules were produced using the layer-by-layer (LBL) assembly method. Microcapsules isolate bacteria from their surroundings, forming a separate microenvironment and greatly improving microorganisms' ability to adapt to adverse environmental conditions. Morphology observation indicated that the pie-shaped bio-microcapsules with a certain thickness could be successfully prepared through LBL assembly method. Surface analysis showed that the LBL bio-microcapsules (LBMs) had large fractions of mesoporous. The biodegradation experiments of toluene and the determination of toluene degrading enzyme activity were also carried out under external adverse environmental conditions (i.e., unsuitable initial concentrations of toluene, pH, temperature, and salinity). The results showed that the removal rate of toluene by LBMs can basically reach more than 90% in 2 days under adverse environmental conditions, which is significantly higher than that of free bacteria. In particular, the removal rate of toluene by LBMs can reach four times that of free bacteria at pH 3, which indicates that LBMs maintain a high level of operational stability for toluene degradation. Flow cytometry analysis showed that LBL microcapsules could effectively reduce the death rate of the bacteria. The results of the enzyme activity assay showed that the enzyme activity was significantly stronger in the LBMs system than in the free bacteria system under the same unfavorable external environmental conditions. In conclusion, the LBMs were more adaptable to the uncertain external environment, which provided a feasible bioremediation strategy for the treatment of organic contaminants in actual groundwater.

Study on the Enhanced Remediation of Petroleum-Contaminated Soil by Biochar/g-C3N4 Composites.

This work developed an environmentally-friendly soil remediation method based on BC and g-C3N4, and demonstrated the technical feasibility of remediating petroleum-contaminated soil with biochar/graphite carbon nitride (BC/g-C3N4). The synthesis of BC/g-C3N4 composites was used for the removal of TPH in soil via adsorption and photocatalysis. BC, g-C3N4, and BC/g-C3N4 have been characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller surface area analyzer (BET), FT-IR, and X-ray diffraction (XRD). BC/g-C3N4 facilitates the degradation due to reducing recombination and better electron-hole pair separation. BC, g-C3N4, and BC/g-C3N4 were tested for their adsorption and photocatalytic degradation capacities. Excellent and promising results are brought out by an apparent synergism between adsorption and photocatalysis. The optimum doping ratio of 1:3 between BC and g-C3N4 was determined by single-factor experiments. The removal rate of total petroleum hydrocarbons (TPH) by BC/g-C3N4 reached 54.5% by adding BC/g-C3N4 at a dosing rate of 0.08 g/g in a neutral soil with 10% moisture content, which was 2.12 and 1.95 times of BC and g-C3N4, respectively. The removal process of TPH by BC/g-C3N4 conformed to the pseudo-second-order kinetic model. In addition, the removal rates of different petroleum components in soil were analyzed in terms of gas chromatography-mass spectrometry (GC-MS), and the removal rates of nC13-nC35 were above 90% with the contaminated soil treated by BC/g-C3N4. The radical scavenger experiments indicated that superoxide radical played the major role in the photocatalytic degradation of TPH. This work definitely demonstrates that the BC/g-C3N4 composites have great potential for application in the remediation of organic pollutant contaminated soil.

Hsp-27 levels and thrombus burden relate to clinical outcomes in patients with ST-segment elevation myocardial infarction.

High thrombus burden, subsequent distal embolization, and myocardial no-reflow remain a large obstacle that may negate the benefits of urgent coronary revascularization in patients with ST-segment elevation myocardial infarction (STEMI). However, the biological function and clinical association of Hsp-27 with thrombus burden and clinical outcomes in patients with STEMI is not clear. Consecutive patients (n = 146) having STEMI undergoing primary percutaneous coronary intervention (pPCI) within 12 hours from the onset of symptoms were enrolled in this prospective study in the Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, Shangdong, P.R. China. Patients were divided into low thrombus burden and high thrombus burden groups. The present study demonstrated that patients with high-thrombus burden had higher plasma Hsp-27 levels ([32.0 ± 8.6 vs. 58.0 ± 12.3] ng/mL, P < 0.001). The median value of Hsp-27 levels in all patients with STEMI was 45 ng/mL. Using the receiver operating characteristic (ROC) curve analysis, plasma Hsp-27 levels were of significant diagnostic value for high thrombus burden (AUC, 0.847; 95% CI, 0.775-0.918; P < 0.01). The multivariate cox regression analysis demonstrated that Hsp-27 > 45 ng/mL (HR 2.801, 95% CI 1.296-4.789, P = 0.001), were positively correlated with the incidence of major adverse cardiovascular events (MACE). Kaplan-Meier survival analysis demonstrated that MACE-free survival at 180-day follow-up was significantly lower in patients with Hsp-27 > 45 ng/mL (log rank = 10.28, P < 0.001). Our data demonstrate that plasma Hsp-27 was positively correlated with high thrombus burden and the incidence of MACE in patients with STEMI who underwent pPCI.

A peculiar lens-shaped structure observed in the South China Sea.

Lens-shaped structures within thermocline potentially play a significant role in subsurface transport of mass, heat, and salt in the global ocean. Whilst such structures have been documented in many oceanic regions, none has been observed in the China Seas. This study reports on observations of a lens-shaped structure within thermocline in the southwestern South China Sea in September 2007. This structure had a maximum thickness of approximately 60 m and a horizontal extent exceeding 220 km. This lens was peculiar in that its size is larger than most similar structures documented in the literature. The lens core was characterized by well-mixed water with higher temperature (~28.8 °C), lower salinity (~33.3) and lower potential vorticity (PV) compared to the surrounding waters. Based on an ocean reanalysis, possible generation mechanism of the lens is explored by examining the evolution of surface and subsurface thermohaline properties, and an analysis of vertical PV flux. The lens was likely generated by a mixture of the local mixed-layer water and the water from the coastal jet separation site.

Assessment of acute lung injury/acute respiratory distress syndrome using B-type brain natriuretic peptide.

OBJECTIVES: To investigate the clinical value of B-type natriuretic peptide (BNP) in the assessment of severity and prognosis in acute lung injury/acute respiratory distress syndrome (ALI/ARDS). METHODS: Plasma BNP level, arterial blood gases, serum C-reactive protein level, alveolar-arterial oxygen tension difference and oxygenation index were measured in patients with and without ALI/ARDS within 24 h of admission to an intensive care unit. Patients with ALI/ARDS were divided into mild, moderate or severe groups according to the degree of hypoxaemia. Survival >28 days was recorded. RESULTS: A total of 59 patients with ALI/ARDS and 14 patients without ALI/ARDS were included in the study. Of the patients with ALI/ARDS, 18 had mild hypoxaemia, 20 had moderate hypoxaemia and 21 had severe hypoxaemia. The mean ± SD BNP level was significantly higher in all three ALI/ARDS groups (92.41 ± 28.19 pg/ml, 170.64 ± 57.34 pg/ml and 239.06 ± 59.62 pg/ml, respectively, in the mild, moderate and severe groups) than in the non-ALI/ARDS group (47.27 ± 19.63 pg/ml); the increase in BNP level with increasing severity was also statistically significant. When divided according to outcome, the BNP level in the death group (267.07 ± 45.06 pg/ml) was significantly higher than in the survival group (128.99 ± 45.42 pg/ml). CONCLUSIONS: The BNP level may be of value in evaluating severity and prognosis in patients with ALI/ARDS.

Effects of N-butylphthalide on the activation of Keap1/Nrf-2 signal pathway in rats after carbon monoxide poisoning.

Carbon monoxide (CO) is the leading cause of death by poisoning all over the world and may result in neuropathologic changes and cognitive and neurologic sequelae, yet little is known regarding its outcomes. The present study aimed to evaluate the neuroprotective effects of N-butylphthalide (NBP) against brain damage after acute CO poisoning. The animal model of CO poisoning was established by exposed to 1000 ppm CO in air for 40 min and then to 3000 ppm for another 20 min. RT-PCR was used to assess the expressions of apoptosis-associated genes Bcl-2 mRNA and Bax mRNA. Mitochondrial membrane potential (MMP) was detected by fluorescent probe JC-1. Immunohistochemistry stain and Western blot assay were used to evaluate the expression levels of Kelch-like ECH-associated protein 1 (Keapl), nuclear factor erythroid 2-related factor 2 (Nrf-2) and NAD(P)H: quinone oxidoreductase 1(NQO-1). CO poisoning could increase the levels of Bcl-2 mRNA and Bax mRNA expressions, and obviously decrease the MMP of cells. NBP treatment could maintain the high MMP, significantly up-regulate Bcl-2 mRNA and down-regulate Bax mRNA expression, and the ratio of Bcl-2 mRNA/Bax mRNA expressions was higher than that in the CO poisoning group (P<0.05). CO poisoning could start oxidative stress response. The expressions of Keap1, Nrf-2 and NQO-1 proteins significantly increased at 1, 3 and 7 day after NBP administration as compared with the CO poisoning group (P<0.01). These findings suggest that N-butylphthalide may protect mitochondrial function, balance the expressions of anti-apoptosis genes and pro-apoptosis genes, be in part associated with activation of Keap1-Nrf-2/antioxidant response element (ARE) signaling pathway, and play a neuroprotective role in brain damage after acute CO poisoning.

Effects of N-Butylphthalide on the expressions of Nogo/NgR in rat brain tissue after carbon monoxide poisoning.

Carbon monoxide (CO) intoxication is one of the most common types of poisoning worldwide, and may result in neuropathologic sequelae, yet its pathogenesis is not clear and there is no optimal management strategy for patients with CO poisoning. In this study, the rat model of CO poisoning was established in a hyperbaric chamber by CO exposure. Rats were administered orally N-Butylphthalide (NBP) at a dose of 1 ml/100g. Neuronal apoptosis was assessed by TUNEL stain and flow cytometry. The expressions of neurite outgrowth inhibitor (Nogo), myelin-associated glycoprotein (MAG) and Nogo receptor-1 (NgR1) were observed in rat brain tissue by immunohistochemistry and double immunofluorescence staining. As we expected, CO poisoning could start the mechanism of apoptosis. The number of apoptotic cells and the early neuronal apoptosis percentage (EAR) were significantly increased at 1 day, 3 day after CO exposure. NBP treatment obviously reduce neuronal apoptosis and the EAR (P<0.05). CO poisoning could induce Nogo, MAG and NgR1 expressions. The increased Nogo, MAG and NgR1 proteins were still observed at 4 week after CO poisoning. NBP could significantly reduce the levels of Nogo and NgR1 proteins. Then we suspected that the expressions of Nogo, MAG and NGR1 proteins might be associated with brain injury and demyelination induced by CO poisoning. NBP might inhibit neuronal apoptosis and the EAR, down-regulate the expressions of Nogo and NgR1 proteins (but not MAG), and play a neuro-protective role in brain damage after acute CO poisoning.