Transition-metal dichalcogenide 1T − VSe2experimentally exhibits multiple charge density wave (CDW) orders, but its origin is still under debate. Using first-principles calculations, we investigate ...the origin of CDW orders in 1T − VSe2 and clarify the ground state of CDW in the freestanding monolayer. Our results show that both Fermi-surface nesting and electron-phonon coupling account for the 4 × 4 × 3 CDW superstructure in bulk 1T − VSe2, while the momentum-dependent electron-phonon coupling-induced √ 7 × √ 3 CDW superstructure is most stable in the freestanding monolayer 1T − VSe2. For monolayer 1T − VSe2, the substrate-induced compressive strain can turn the ground state into the 4 × 4 CDW superstructure, while tensile strain preserves the √ 7 × √ 3 superstructure. Our results demonstrate the origin of the CDW orders in 1T − VSe2 and shed light on the experimental observation of multiple CDW orders in monolayer 1T − VSe2.
The Cadmium (Cd)‐polluted soils are is an increasing concern worldwide. Phytoextraction of Cd pollutants by high biomass plants, such as sweet sorghum, is considered an environmentally‐friendly, ...cost‐effective and sustainable strategy for remediating this problem. Nitrogen (N) is a macronutrient essential for plant growth, development and stress resistance. Nevertheless, how nitrate, as an important form of N, affects Cd uptake, translocation and accumulation in sweet sorghum is still unclear.
In the present study, a series of nitrate levels (N1, 0.5 mm; N2, 2 mm; N3, 4 mm; N4, 8 mm and N5, 16 mm) with or without added 5 μm CdCl2 treatment in sweet sorghum was investigated hydroponically.
The results indicate that Cd accumulation in the aboveground parts of sweet sorghum was enhanced by optimum nitrate supply, resulting from both increased dry weight and Cd concentration. Although root‐to‐shoot Cd translocation was not enhanced by increased nitrate, some Cd was transferred from cell walls to vacuoles in leaves. Intriguingly, expression levels of Cd uptake and transport genes, SbNramp1, SbNramp5 and SbHMA3, were not closely related to increased Cd as affected by nitrate supply. The expression of SbNRT1.1B in relation to nitrate transport showed an inverted ‘U’ shape with increasing nitrate levels under Cd stress, which was in agreement with trends in Cd concentration changes in aboveground tissues.
Based on the aforementioned results, nitrate might regulate Cd uptake and accumulation through expression of SbNRT1.1B rather than SbNramp1, SbNramp5 or SbHMA3, the well‐documented genes related to Cd uptake and transport in sweet sorghum.
Nitrate might regulate Cd uptake and accumulation through the expression of SbNRT1.1B rather than SbNramp1, SbNramp5 and SbHMA3, the well‐documented genes related to Cd uptake and transport in sweet sorghum.
Background: We previously identified DnaJ-like heat shock protein (HLJ1) as a gene associated with tumor invasion. Here, we investigated the clinical significance of HLJ1 expression in non–small-cell ...lung cancer (NSCLC) patients and its role in cancer progression. Methods: We induced HLJ1 overexpression or knockdown in human lung adenocarcinoma CL1–5 cells and analyzed cell proliferation, anchorage-independent growth, in vivo tumorigenesis, cell motility, invasion, and cell cycle progression. Expression of genes that act downstream of HLJ1 was examined by DNA microarray analysis, pathway analysis, and western blotting. We measured HLJ1 expression in tumors and adjacent normal tissues of 71 NSCLC patients by quantitative reverse transcription–polymerase chain reaction. Associations between HLJ1 expression and disease-free and overall survival were determined using the log-rank test and multivariable Cox proportional hazards regression analysis. Validation was performed in an independent cohort of 56 NSCLC patients. Loss of heterozygosity (LOH) mapping of the HLJ1 locus was analyzed in 48 paired microdissected NSCLC tumors. All statistical tests were two-sided. Results: HLJ1 expression inhibited lung cancer cell proliferation, anchorage-independent growth, tumorigenesis, cell motility, and invasion, and slowed cell cycle progression through a novel STAT1/P21WAF1 pathway that is independent of P53 and interferon. HLJ1 expression was lower in tumors than in adjacent normal tissue in 55 of 71 patients studied. NSCLC patients with high HLJI expressing tumors had reduced cancer recurrence (hazard ratio HR = 0.47; 95% confidence interval CI = 0.23 to 0.93; P = .03) and longer overall survival (HR = 0.38; 95% CI = 0.16 to 0.89; P = .03) than those with low-expressing tumors. Validation in the independent patient cohort confirmed the association between HLJ1 expression and patient outcome. LOH mapping revealed high frequencies (66.7% and 70.8%) of allelic loss and microsatellite instability (87.5% and 95.2%) of the HLJ1 locus at chromosome 1p31.1. Conclusions: HLJ1 is a novel tumor suppressor in NSCLC, and high HLJ1 expression is associated with reduced cancer recurrence and prolonged survival of NSCLC patients.
Aluminum matrix composites reinforced with Ti-coated diamond particles (Al/Ti-diamond composites) were produced by squeeze casting. The plating time of molten-salt was varied to investigate the ...effects on the phase structure and thickness of Ti coating on diamond particles. The highest tensile strength of 76MPa was obtained for the composite with 90min plating time. In this composite, a reasonable thickness of TiC layer was found to tightly connect Al matrix with diamond reinforcements. The tensile strength decreased when the plating time is longer than 90min, owing to weak interfacial bonding between additionally formed Ti layer and Al matrix. The results show that appropriate selection of Ti coating can effectively improve interfacial bonding and tensile strength of Al/diamond composites.
To understand the passive smoking exposure status in adults aged ≥40 years in China.
Local residents aged ≥40 years were enrolled as study subjects from 125 areas of chronic obstructive pulmonary ...disease (COPD) surveillance during 2014-2015 and 2019-2020 in 31 provinces of China. A total of 74 559 adults aged ≥40 years were selected through multi-stage stratified cluster sampling for a face to face questionnaire survey and the data from 64 142 study subjects were used for the analysis. The passive smoking exposure rate, the proportions of the adults reporting passive smoking exposure at four types of places and the proportion of the adults living with daily smokers were described by using complicated sampling weighting method, the related factors were analyzed and the results were compared with the data of COPD surveillance during 2014-2015.
The passive smoking exposure rate in the adults aged ≥40 years was 46.4% (95%
: 44.1%-48.8%) in China during 2019-2020, and the rate was higher in women (47.2%, 95%
:44.8
To understand the current status of occupational exposure to dust or harmful gases and occupational protection in people aged ≥40 years in China, and provide data support for the prevention and ...control of occupational dust or harmful gas exposure.
The data were obtained from the surveillance for chronic obstructive pulmonary disease (COPD) in adults aged ≥40 years selected by multi-stage stratified cluster sampling from 125 surveillance points in 31 provinces (autonomous regions and municipalities) during 2014-2015 and 2019-2020, and relevant information about occupational dust or harmful gas exposure and protection measures were collected through face-to-face interviews. Occupational dust or harmful gas exposure rate and occupational protection rate were estimated by using weighting complex sampling methods, and then the results were compared.
From 2014 to 2015 and from 2019 to 2020, a total of 71 061 and 71 023 individuals aged ≥40 years were surveyed, respectively. The rate of occupational exposure to dust
A novel light-weight and high-toughness in-situ dendrite/metallic glass matrix composites (MGMCs) with a composition of Ti58Zr12Ni6Ta13Be11 was designed. Quasi-static and dynamic compressive ...properties of MGMCs were investigated. The alloys showed excellent compressive properties of the maximum strength over 1.6 GPa and the total strain over 10% under the quasi-static loading. Under dynamic compressive loading, the compressive strength increased up to 1.9 GPa, whereas the total strain is nearly undiminished exhibited favourable plastic deformation. Deformation mechanisms related to the improvement of strength and ductility were investigated thoroughly by focusing on how ductile dendrites affected the initiation and propagation of deformation bands, accompanied with the localization of deformed bands and effects of ω phase precipitation, shear slipping, thermo softening, and melting. A constitutive relationship is obtained by modified Johnson-Cook plasticity model, which is applied to model the dynamic flow stress behavior. In addition, under dynamic compression, the strain rate effect of the yielding strength exerts distinctly positive strain rate sensitivity (SRS), which can be attributed to the dendrite-dominated plastic deformation fracture mechanism related to the significant accommodation of deformed bands and dislocation in the dendrites to the macroscopic dynamic deformation at relative strain rates.
•The paper developed a novel MGMCs containing β phase and ω phase in the dendrites.•The alloys showed excellent compressive properties under quasi-static and dynamic compressive loading.•A constitutive relationship is constructed using modified J-C model.
The positive-strangeness baryon resonance Θ+ is observed in photoproduction of the nK+K0s final state with the SAPHIR detector at the Bonn ELectron Stretcher Accelerator ELSA. It is seen as a peak in ...the nK+ invariant mass distribution with a 4.8σ confidence level. We find a mass MΘ+=1540±4±2 MeV and an upper limit of the width ΓΘ+<25 MeV at 90% c.l. The photoproduction cross section for K0Θ+ is in the order of 300 nb. From the absence of a signal in the pK+ invariant mass distribution in γp→pK+K− at the expected strength we conclude that the Θ+ must be isoscalar.
Purpose
Multiple sclerosis (MS) is a disease characterized by inflammatory demyelinated lesions. New treatment strategies are being developed to stimulate myelin repair. Quantitative myelin imaging ...could facilitate these developments. This first-in-man study aimed to evaluate
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CMeDAS as a PET tracer for myelin imaging in humans.
Methods
Six healthy controls and 11 MS patients underwent MRI and dynamic
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CMeDAS PET scanning with arterial sampling. Lesion detection and classification were performed on MRI.
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CMeDAS time-activity curves of brain regions and MS lesions were fitted with various compartment models for the identification of the best model to describe
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CMeDAS kinetics. Several simplified methods were compared to the optimal compartment model.
Results
Visual analysis of the fits of
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CMeDAS time-activity curves showed no preference for irreversible (2T3k) or reversible (2T4k) two-tissue compartment model. Both volume of distribution and binding potential estimates showed a high degree of variability. As this was not the case for 2T3k-derived net influx rate (K
i
), the 2T3k model was selected as the model of choice. Simplified methods, such as SUV and MLAIR2 correlated well with 2T3k-derived K
i
, but SUV showed subject-dependent bias when compared to 2T3k. Both the 2T3k model and the simplified methods were able to differentiate not only between gray and white matter, but also between lesions with different myelin densities.
Conclusion
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CMeDAS PET can be used for quantification of myelin density in MS patients and is able to distinguish differences in myelin density within MS lesions. The 2T3k model is the optimal compartment model and MLAIR2 is the best simplified method for quantification.
Trial registration.
NL7262. Registered 18 September 2018.
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