To have a fully first-principles description of the moiré pattern in transition-metal dichalcogenide heterobilayers, we have carried out density functional theory calculations on a MoTe
(9 × 9)/MoS
...(10 × 10) stacking, which has a superlattice larger than an exciton yet not large enough to justify a continuum model treatment. Lattice corrugation is found to be significant in both monolayers, yet its effect on the electronic properties is marginal. We reveal that the variation of the average local potential near Mo atoms in both MoTe
and MoS
layers displays a conspicuous moiré pattern. They are the intralayer moiré potentials correlating closely with the spatial variation of the valence band maximum and conduction band minimum. The interlayer moiré potential, defined as the difference between the two intralayer moiré potentials, changes roughly in proportion to the band gap variation in the moiré cell. This finding might be instructive in chemical engineering of van der Waals bilayers.
Abstract
This paper studies the characteristics of the insulation shear belt produced by the fracture of the vents of the gunhead desceptor and the reasons for its formation when the shell is fired. ...The results show that: During the explosion, the rupture of the degenerator belongs to the ligament fracture, and the insulation shear belt produced at the time of the break plays the role of “prefabricated crack”. The smaller the microstructure and grain of alloy steel, the easier it is to promote the production of insulation shear belt.
Tiller onion is a biennial herb and a fascicular variety of onion. Tiller onion has strong tillering ability and can produce up to ten bulbs per plant. It is widely cultivated due to nutrition and ...special flavor. In July 2020, we observed a disease that seriously affected the normal growth of tiller onion in Halahai Town, Nongan County, Jilin Province, China. At least 70% of tiller onions in the field were affected by this disease. Aboveground parts of the symptomatic plants showed stunted growth, wilting and drying. Underground parts of infected plants were shown that onion increase tiller number but did not grow and expand. Root appeared red lesions and rot in severe cases. The bulb disc appeared brown to dark brown rot. Symptomatic roots were cut into 0.5 cm pieces and surface-sterilized by dipping in 75% ethanol for 60 s, 3% NaOCl for 3 min, and rinsing three times with sterile distilled water. Pieces were placed on potato dextrose agar (PDA) plates and incubated at 25±1℃ for 4 days. Fifteen isolates were obtained and pure-cultured through single-sporing. On PDA plates, the colonies initially had white aerial mycelia that then turned pale purple. The color of the colonies on the back of the plates was purple. Macroconidia were hyaline, falcate and 14.4 to 38.7 × 1.2 to 3.0 µm. Microconidia were hyaline, reniform or elliptic, unicellular or bicellular and were 7.62 to 19.61 µm in length, and 3.23 to 8.41 µm in width. Based on these morphological and culture characteristics, the causal agent was tentatively identified as F. proliferatum. To confirm the pathogen identity, segments of the internal transcribed spacer region of the rRNA gene ( ITS, primers ITS4 and ITS5, White et al., 1990), β-tubulin gene (TUB2, primers T1 and T2, O'Donnell and Cigelnik, 1997), and translation elongation factor 1-alpha gene (TEF-1α, primers EF1 and EF2 from O'Donnell et al., 1998) were amplified by PCR. Per the BLASTN search, TEF-1α (Accession No. OL355013), TUB2 (Accession No. OL355012), and ITS (Accession No. OL355011) queries showed 99.26%, 100%, and 99.82% homology to F. proliferatum GenBank accessions KU872098, MH398224, and MH997878, respectively. Pathogenicity of fifteen isolates of F. proliferatum from tiller onion was confirmed by inoculating healthy tiller onion roots and bulb disc with a spore suspension (1 × 106 spores/ml) produced on PDA. For each treatment, five plants were injected with 5 ml of spore suspension. Control plants (n=5) were injected with sterilized water. All plants were enclosed in plastic bags for 48 h in a greenhouse at 28℃ and 12 h/d light cycle. After 10 days, inoculated plants showed similar symptoms to those on the original diseased plants, while control plants remained symptomless. F. proliferatum was successfully re-isolated from symptomatic plants to fulfill Koch's postulates. Diseases caused by F. proliferatum are only reported in A. cepa. To our knowledge, this is the first report of F. proliferatum in Allium cepa L. var. agrogatum Don in China. Our findings are important for informed surveillance of the disease in China as F. proliferatum infection can not only reduce the quality and yield of tiller onion but also can contaminate the bulbs with harmful mycotoxins.
High-index perovskite ferroelectric thin films possess excellent dielectric permittivity, piezoelectric coefficient, and exotic ferroelectric switching properties. They also exhibit complications in ...the ferroelastic domains, misfit dislocations, and strain-relaxation behaviors. Exploring the relationship of the ferroelastic domains and misfit dislocations may be of benefit for promoting the high-quality growth of these thin films. Here, the strain field of the ferroelastic domains and misfit dislocations in 101-oriented PbTiO3/(La, Sr)(Al, Ta)O3 epitaxial thin films were investigated by advanced aberration-corrected (scanning) transmission electron microscopy (TEM) combined with geometry phase analysis (GPA). Two types of misfit dislocations with projected Burgers vectors of a001 or a100 on the (010) plane were elucidated, whose strain fields included in-plane strain and lattice rotation coupled with the c domains above them. Besides, it was demonstrated that the coupling was kept inside the PbTiO3 films when the film thickness was increased. Furthermore, the polarization rotation was observed in both narrow c domains and around the misfit dislocation cores, which may be attributed to the flexoelectric effect. These results are expected to provide useful information for understanding the nucleation and propagation mechanism of ferroelastic domains and for further modifying the growth of high-index ferroelectric thin films.
BACKGROUND AND AIMSEarly prediction of severe acute pancreatitis (SAP)would be helpful for triaging patients to the appropriate level of care and intervention. The aim of this study is to compare the ...performance of the Change in Amylase And Body mass index (CAB) score and BISAP score for predicting SAP. PATIENTS AND METHODSA total of 406 with AP were enrolled. The age, gender, body mass index(BMI), blood urea nitrogen determined at the time of admission and serum amylase determined on day 1 and day 2 after hospitalization were collected and analyzed statistically. RESULTSMultivariable analysis confirmed that blood urea nitrogen (OR 1.06; 95%CI 1.03-1.09) and percentage change in amylase day 2 (OR 0.75; 95%CI 0.65-0.87) were independently associated with development of SAP. No statistically significant association was observed between BMI (OR 1.04; 95%CI 0.951.13) and severity of acute pancreatitis. The area under the receiver operating characteristic curve for Body mass index (BMI), percentage change in amylase day 2, BISAP score and CAB score were 0.57±0.05, 0.68±0.04, 0.84±0.03 and0.53±0.05, respectively. CONCLUSIONBISAP is more accurate for predicting the severity of acute pancreatitis than the CAB score.
MnxBi100−x (x=48, 50, 55 and 60) alloys were prepared by the induction melting technique, and subjected to melt spinning and subsequent ball milling. XRD shows that the as-milled powders were mainly ...composed of LTP MnBi. Increasing melt spinning speed and reducing annealing treatment time can restrain the segregation of Mn from MnBi liquid during the peritectic reaction, which increases the LTP MnBi content. High energy ball milling results in the coercivity increase of MnBi powders. With increasing milling time, the coercivity increases initially and then decreases gradually. After ball milling for 4h, the coercivity of the MnxBi100−x powders is 11.4kOe for x=48 and 14.8kOe for x=55. The optimal composition of Mn48Bi52 with more LTP has an M2.2T of 49.98emu/g and an Mr of 33.57emu/g.
► The optimal composition is Mn48Bi52 with more LTP MnBi. ► Melt spinning and annealing process are effective for getting more LTP MnBi. ► Mn48Bi52 exhibits a coercivity of 11.4kOe.
Objectives
The HIV epidemic is worsening among men who have sex with men (MSM) in China, especially among those who are younger than 25 years old younger MSM (YMSM). The aim of the study was to ...compare the prevalences of HIV incidence and recent HIV infection as well as factors associated with recent HIV infection in YMSM and older MSM (OMSM).
Methods
A multicentre cross‐sectional survey was conducted among 4496 MSM recruited from seven Chinese cities. YMSM were defined as those aged < 25 years. Data on demographics and sexual behaviours were collected using structural questionnaires. Blood samples were tested for recent HIV infection and other sexually transmitted infections.
Results
Among the participants, 1313 were YMSM and 3183 were OMSM. Compared with OMSM, YMSM had a higher prevalence of recent HIV infection 5.4% (71 of 1313) for YMSM vs. 3.6% (115 of 3175) for OMSM; P = 0.006 and a higher HIV incidence 11.8 per 100 person‐years (PY) (95% confidence interval (CI) 9.0–14.5) for YMSM vs. 7.6 per 100 PY (95% CI 6.3–9.0) for OMSM. The incidence increased with age among YMSM, especially between the ages of 16 and 21 years. In contrast, the incidence declined with age among OMSM. Anal bleeding, recreational drug use, syphilis and herpes simplex virus 2 (HSV‐2) infection were independent risk factors for recent HIV infection among YMSM. The prevalence of all these risk factors increased with age between the ages of 16 and 21 years. Anal bleeding (19.8%) and recreational drug use (19.5%) had the highest adjusted population attributable fractions (aPAFs) among YMSM. The highest aPAFs of anal bleeding (27.4%) and syphilis infection (25.5%) were found between the ages of 19 and 21 years.
Conclusions
The HIV incidence in Chinese YMSM was significantly higher than that in OMSM. YMSM aged 16–21 years had an extremely high risk of recent HIV infection.
Purpose: Sepsis, which is deemed as a systemic inflammation reaction syndrome in the face of infectious stimuli, is the primary cause of death in ICUs. Sepsis-induced cardiomyopathy (SIC) may derive ...from systemic inflammation reaction and oxidative stress. Retinoic acid (RA) is recognized by its beneficial roles in terms of the immunoresponse to infections and antioxygen actions. However, the treatment efficacy and potential causal links of RA in SIC are still elusive. Methods: By virtue of the STITCH database, we identified the targets of RA. Differentially expressed genes in SIC were acquired from the GEO database. The PPI network of intersected targets was established. GO and KEGG pathway enrichment analysis was completed. Hub genes were analyzed by cytoHubba plug-in. In the process of experimental validation, a mouse sepsis model was established by lipopolysaccharide (LPS), and the treated mice were intraperitoneally injected with RA or Dexamethasone (DEX) 60 min prior to LPS injections. Survival conditions, cardiac functions and antioxidant levels of the mice were assessed. Cardiac inflammation and injury were detected by HE and TUNEL. The levels of key genes and signal pathway expression were analyzed by RT-PCR and Western blot. Results: PPARA, ITGAM, VCAM-1, IGF-1 and IL-6 were identified as key therapeutic targets of RA by network pharmacology. PI3K-Akt signaling pathway is the main regulatory pathway of RA. In vivo researches unraveled that RA can improve the survival rate and cardiac function of LPS-treated mice, inhibit inflammatory factors and myocardial injury, and regulate the expression of key therapeutic targets and key pathways, which is PI3K-Akt signaling pathway. Conclusion: Network pharmacological method offers a predicative strategy to explore the treatment efficacy and causal links of RA in endotoxemic myocarditis. Through experimental verification, we discover that RA can reduce lipopolysaccharide-induced cardiac dysfunction by regulating the PI3K-Akt signaling pathway and key genes. Keywords: retinoic acid, lipopolysaccharide, sepsis-induced cardiomyopathy, network pharmacology, inflammatory response
Carbon coating substantially promotes electron transport through LiFePO4 nanoparticles at the positive electrode in Li-ion batteries and approaches to forming thin, tightly attached, and uniform ...carbon layers are extremely desirable. On the basis of our recent first principles computational discovery that the graphite crystallites are more likely standing on the LiFePO4 (010) surface via C–O bonding rather than lying on van der Waals forces, we have in this work searched promising co-coating substances which can reinforce the perpendicular orientation of graphite crystallites by strengthening the C/LiFePO4 binding. Among the three supervalent elements we have studied, Sc (3+), Ti (4+), and V (5+), Sc and Ti are found to show good performance. The binding energy of perpendicular graphite on the LiFePO4 (010) surface increases noticeably from 0.52 to 0.58 (Sc) and 0.61 (Ti) eV/Å, whereas the binding of a parallel graphene sheet with the same surface is nearly unchanged. A strengthened perpendicular graphite orientation is very welcome for leaving diffusion channels of Li unblocked.
Phthalates adversely affect the male reproductive system in humans. Through gas chromatography-mass spectrometry analysis, we investigated the residual profile and levels of 15 phthalates in 90 goat ...milk-based infant formulas from 15 commercial brands of 10 dairy enterprises located in Shaanxi Province, China. In general, dibutyl phthalate was the most detected phthalate, followed by bis(2-ethylhexyl) phthalate, diisobutyl phthalate, and dimethyl phthalate; their geometric mean concentrations in the formulas were 38.1, 24.2, 16.6, and 8.7μg/kg, respectively. Other phthalates were not detected in the investigated samples. No significant differences were found in the phthalate levels among different stages of infant formulas, even though the samples were packaged in different types of containers. These findings demonstrate that goat milk-based infant formulas may represent the main source of exposure to phthalates in infants.
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