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Molybdenum disulfide (MoS2), a typical two-dimensional layered semiconductor material, is widely studied due its excellent electronic properties in atomic scale. In this study, we achieved the growth of large size few-layer MoS2 films by using molybdenum boat with vertical shield at the end to carry MoO3 precursor in the chemical vapor deposition (CVD) system. The optical microscopy reveals the morphology and lateral size of as-grown films. The Raman spectrum testified that the synthesized films are few-layer MoS2 with defects. Metal-oxide-semiconductor field effect transistors (MOSFETs) based on CVD-grown MoS2 are fabricated, presenting n-type transportation with ION/IOFF ratio about 103. The transportation behaviour of MoS2 MOSFETs is changed from n-type to ambipolar by introducing nitrogen plasma into MoS2 films. The electron or hole transportation in MoS2 is controlled by gate-source voltage. The ambipolar MOSFETs show ION/IOFF ratio about 103.

Tubular boron clusters represent a class of extremely unusual geometries that can be regarded as a key indicator for the 2D-to-3D boron structural evolution as well as the embryos for boron nanotubes. While a good number of pure boron or metal-doped boron tubular clusters have been reported so far, most of them are two-ring tubular structures, and their higher-ring analogues are very scarce. We report herein the first example of a four-ring tubular boron motif in the cagelike global minimum of Be

The bonding situation in the tricoordinated beryllium phenyl complexes [BePh

Multi-layer molecular rotors represent a class of unique combination of topology and bonding, featuring a barrier-free rotation of one layer with respect to other layers. This emerging fluxional behavior has been found in a few doped boron clusters. Herein, we strongly enrich this intriguing family followed by an effective design strategy, summarized as essential factors: i) considerable electrostatic interactions originated from a strong charge transfer between layers; ii) the absence of strong covalent bonds between layers; and iii) fully delocalized σ/π electrons from at least one layer. We found that planar hypercoordinate motifs consisting of monocyclic boron rings and metals with σ + π dual aromaticity can be regarded as one promising layer, which can support the suspended X

Six-valence-electron planar pentacoordinate beryllium (ppBe) is explored herein as a global minimum, which is only constructed by s-block metals in BeM5+ (M = Cu, Ag, Au). The bonding in ppBe can be regarded as the excited-stated Be with a 2px12py1 electronic configuration, forming electron sharing with doublet M5+ motifs followed by two sets of Be(p∥) → [M5+] σ donations and one Be(s) ← [M5+] σ back-donation. Thus, the σ aromaticity originating from three delocalized σ orbitals gives rise to the whole stability of the high D5h-symmetry ppBe and strongly enriches s-block planar hypercoordinate bonding.

The triply bonded heavier main-group compounds have a textbook trans-bent geometry, in contrast to a familiar linear form found for the lightest analogues. Strikingly, the unexpected linear group 13 E≡E triple bonds were herein found in the D4h -symmetry E2 Li62+ clusters, and they possess a large barrier (>18.0 kcal/mol) towards the dissociation of Li+ . The perfectly surrounded Li4 motifs and two linear coordinated Li atoms strongly suppress the increasing nonbonded electron density of heavier E atoms, making two degenerate π bonds and one multi-center σ bond in linear heavier main-group triple bonds. The surrounding Li6 motifs not only creates an effective electronic structure to form a linear E≡E triple bond, but the resulting electrostatic interactions account for the highly stable global E2 Li62+ clusters.

A new class of beryllium-boron clusters, beryllo-borospherene, is described herein theoretically. When beryllium is gradually added to the B

We report herein evidence of EE triple bonds (E = Group 13) promoted by the perpendicularly surrounding M4 (M = Li and Na) motifs. The global minimum of E2M4 (E = B, Al, and Ga) is a D4h-symmetry structure where E–E is surrounded perpendicularly by square M4 motifs, whereas the Cs-symmetry structure formed by E–E–M surrounded partially by M3 motifs is the lowest-energy structure for E = In and Tl. Chemical bonding reveals that strong charge transfer from M4 to E2 dimer not only provides efficient electrons to form EE triple bonds, but also the resulting electrostatic interactions between M4 and E2 play a driving force to stabilize these intriguing triply bonded species.

The unexpected linear group 13 EE triple bonds were herein uncovered with the D3h-symmetry E2M5+ (M = Li, Na, and K) clusters, where the linear M–EE–M form is perfectly surrounded by M3 motifs. The increasing nonbonded electron density of the heavier main-group elements is the key issue for the trans-bent geometry, and yet it is strongly suppressed in E2M5+, creating two degenerate π bonds and one multi-center σ bond.

The high lignin content of Rosa roxburghii fruits imparts a strong rough taste, which has restricted its use in industry. Little is known about the molecular mechanisms underlying lignin biosynthesis in R. roxburghii fruits. Illumina and single-molecule real-time (SMRT) sequencing platforms were combined to analyze the transcriptomic changes during the ripening of R. roxburghii fruits. After assembly, 67,739 transcripts with an average length of 1866 bp were obtained, of which 17,470 transcripts were differentially expressed during fruit ripening. Biological pathway analysis putatively identified 25 differentially expressed genes were involved in lignin biosynthesis. Furthermore, 43 putative transcription factors were identified, including bHLH, bZip, Dof, MYB, NAC, WRKY, and zf-HD, which were previously reported to control lignin biosynthesis. Among which, 28 were positive transcription factors and 15 were negative. Quantitative RT-PCR analysis of candidate genes and transcription factors correlated with the transcriptome data. The transcriptomic data generated in this study provide a basis for further studies of fruit ripening in R. roxburghii.

The unexpected linear group 13 E[triple bond, length as m-dash]E triple bonds were herein uncovered with the D3h-symmetry E2M5+ (M = Li, Na, and K) clusters, where the linear M-E[triple bond, length as m-dash]E-M form is perfectly surrounded by M3 motifs. The increasing nonbonded electron density of the heavier main-group elements is the key issue for the trans-bent geometry, and yet it is strongly suppressed in E2M5+, creating two degenerate π bonds and one multi-center σ bond.

Alkaloids are a widespread group of basic compounds in herbal medicines and have attracted great interest due to various pharmaceutical activities and desirable druggability. Their distinctive structures make chromatographic separation fairly difficult. Peak tailing, poor resolution, and inferior column-to-column reproducibility are common obstacles to overcome. In order to provide a valuable reference, the methodologies and/or strategies on liquid chromatographic separation of alkaloids in herbal medicines proposed from 2012 to 2019 are thoroughly summarized.

The heteronuclear d-f coordination complexes [Er2Zn2(C6H5COO)10(phen)2] (1), [Ho2Zn2(C6H5COO)10(phen)2] (2), [Pr3Zn6(C6H5COO)21(phen)3] (3), [ErCd(C6H5COO)5(phen)·H2O] (4), [Ho2Cd3(C6H5COO)12(phen)2] (5), [EuCd2(C6H5COO)7(phen)2] (6) (C6H5COOH = benzoic acid;phen = 1,10-phenanthroline) were synthesized by hydrothermal methods, and their structures were studied by single-crystal X-ray diffraction. Complexes 1, 2, 4, and 5 crystallize in the triclinic space group P and complexes 3 and 6 in the monoclinic space group C2/c. The room temperature IR, UV/Vis/NIR absorption, and emission spectra of the six complexes were determined and assigned. In the visible and NIR regions, the emission spectra of complexes show characteristic bands of corresponding LnIII ions, which are attributed to the sensitization from the d block (Zn/Cd-ligand section) and ligands. In comparison with isolated LnIII ions, the NIR emission bands of complexes 1–5 exhibit shifting, broadening and splitting, which are also present in their UV/Vis/NIR absorption spectra. Thus, the two spectra of complexes can evidence each other.

Chinese medicinal formulae are the important means of clinical treatment in traditional Chinese medicine. It is urgent to use modern advanced scientific and technological means to reveal the complicated mechanism of Chinese medicinal formulae because they have the function characteristics of multiple components, multiple targets and integrated regulation. The systematic and comprehensive research model of proteomic is in line with the function characteristics of Chinese medicinal formulae, and proteomic has been widely used in the study of pharmacological mechanism of Chinese medicinal formulae. The recent applications of proteomic in pharmacological study of Chinese medicinal formulae in anti-cardiovascular and cerebrovascular diseases, anti-liver disease, antidiabetic, anticancer, anti-rheumatoid arthritis and other diseases were reviewed in this paper, and then the future development direction of proteomic in pharmacological study of Chinese medicinal formulae was put forward. This review is to provide the ideas and method for proteomic research on function mechanism of Chinese medicinal formulae.

Total glucosides of peony (TGP), containing the effective components of paeoniflorin (Pae), albiflorin (Alb) and so on, are effective parts of Radix Paeoniae Alba. And it possesses extensive pharmacological actions, one of which is hepatoprotective effect. In recent years, abundant of pharmacokinetics and pharmacodynamics research of TGP in hepatoprotective effects have been performed. However, the relative medicine of TGP in hepatoprotective effect has not been developed for clinical application. In order to provide reference for the development and rational clinical application of TGP, the research progresses of pharmacokinetics and pharmacodynamics of TGP in hepatoprotective effect were summarized in this paper. Pharmacokinetics research has clarified the process of absorption, distribution, metabolism and excretion of TGP in vivo, and liver injury disease can significantly influence its metabolic processes. Pharmacodynamics studies suggested that TGP can protect against acute liver injury, non-alcoholic fatty liver diseases (NAFLD), chronic liver fibrosis and liver cancer. However, the action mechanism and in vivo process about hepatoprotective effects of TGP have not been clearly revealed. How liver injury influences the metabolism of TGP and its integrated regulation through multiple targets need to be further studied. The combined pharmacokinetics and pharmacodynamics studies should be performed in favour of medicine development and clinical application of TGP in hepatoprotective effects.

Main electrical wiring is a circuit diagram which is used to meet the production needs of the power transmission and distribution and in accordance with a certain manner and order and use provisions of graphic symbols and text code to connect once equipment (generator transformer switching equipment,etc.) together. It reflects the basic structure and function of traction substations and substation (power generation). In operation, it shows the primary operating mode of substation (power generation) and high voltage grid connection and associated feeder devices and become the basis of controlling and scheduling apparatus. This paper analyzes single-bus connection from the reliability, flexibility and economy point of view, then outlined the typical single-bus wiring switching operation principles and methods.

Based on numerical simulations on the hydrodynamics and dissolved tracer transport, the water exchange ability of the Shuidong Bay, China was simulated, and the regulation effects of different scenarios are evaluated. Through analysis, at present the water exchange ability of the Shuidong Bay is poor with monthly exchange rate only 65%. If the bay was dredged to bottom elevation-3.0m, the monthly exchange rate could be greatly enhanced to 88%. If a new western tidal inlet was constructed, its contribution to the exchange rate is not significant, and the monthly exchange rate is 67%. After comprehensive comparisons, the scenario of proper dredging the Shuidong Bay is suggested.

After hundreds years or even a thousand years of vicissitudes, the earthen sites are destroyed seriously. Protecting these cultural relics has great historical significance and practical value. The protections of the earthen sites include two aspects which are chemistry and physics protection at present. Compared with chemic protection, the structure stability is more important. So the stability reinforcement used bolt is researched for many scholar. Combined the reinforced project of Gaochang earthen site in xinjiang province, and directed toward the new type bolt of geo-filament, the article introduced the construction technology of the geo-filament bolt; in addition, the numerical comparative tests in typical soil medium were implemented and compared the bearing capacity of bolt from the different affections, and the working mechanism for bolt pulled-out test was revealed quantitatively by the overall course simulating analysis. According the test results, the surface state affects the anchor force obviously; the length of bolt is feasible from 0.8-2.0m. the geo-filament bolt is proved to be an excellent material which is used in the walls reinforcement of earthen sites, and it has many typical characters which are advanced technology, novelty techniques and construction facility. Because of that, the new research will play an important part in guiding us to protect the earthen sites.

Although iron plays a critical role in exercise, the regulatory mechanism of iron metabolism remains poorly understood. The aims of the present study were to investigate the effects of different intensity exercise on body iron status and the regulatory mechanism of duodenal iron absorption. Thirty female Sprague-Dawley rats (90–100 g) were randomly divided into three groups: a control group (remained sedentary, CG), a moderately exercised group (swam 1.5 h/day, MG) and a strenuously exercised group (swam with different load, SG). Serum iron status, serum ferritin and Hct were examined after 10 weeks of swimming. Western blot was performed to detect the expression of iron transport proteins: divalent metal transporter1 (DMT1) and ferroportin 1 (FPN1) in duodenal epithelium. The expression of hepcidin mRNA in liver was examined by RT-PCR. The results showed: (1) the body iron status in MG was kept at a high level compared to that of CG and SG, (2) Western blot showed DMT1 with iron responsive element (IRE) and FPN1 in duodenal epithelium which were higher in MG than that of CG and (3) the expression of hepatic hepcidin mRNA was down regulated in MG (p < 0.05). The data suggested that moderate exercise improved iron status and that was likely regulated by increased DMT1 with IRE and FPN1 expression. Hepcidin signaling pathway may involve in the regulation of duodenal iron absorption proteins.

To explore the changes of inferior collicular (IC) neurons after noise exposure cochlea injury in guinea pig to elucidate the encoding mechanism of pure tones, observe the changes of IC gamma-amino butyric acid (GABA) after cochlear damage by acoustic trauma and understand the possible mechanism of symptoms such as noise-induced tinnitus, hyperacusis and loudness recruitment.The responses of IC neurons to pure tone stimuli were observed in guinea pig at Day 1 and Days 11-21 after cochlear damage induced by noise exposure. And the IC neurons of normal guinea pig were assigned as the controls. Reverse transcription-polymerase chain reaction (RT-PCR) was used to measure the concentrations of GABA(A) and GABA(B) receptors.(1) The types of frequency reaction area (FRA) in the experiment group were the same as those in the control group (V-shape 84.8%, W-shape 8.9%, N-shape 6.3%). But the percentages of types were markedly different at Day 1 (V-shape 63.9%, W-shape 18.1%, N-shape, 18.1%) and Days 11-21 (V-shape 84.2%, W-shape 12.3%, N-shape 3.5%) after noise exposure. (2) After noise exposure, there was a marked fault in characteristic frequency (CF) and depth function map corresponding to 4 kHz (noise frequency). The rake ratio of CF and depth linear function map in the experiment group was lower than that of the control group. The control group, Day 1 and Days 11-21 after noise exposure, the rake ratios were 6.6, 5.8, 5.2 respectively. (3) GABA(A)/GABA(B) receptors decreased markedly at Days 1, 11 and 21 post-exposure compared to normal controls. And the values increased gradually with the prolonged time after exposure. The above findings conformed to the changes of electrophysiology of IC.After acoustic trauma, the responses of IC neurons to pure tone stimuli change with the elongation of time. It may be explained by the changes of IC GABA receptors after noise exposure.

Using the largest spectroscopic dataset of stripped-envelope core-collapse supernovae (stripped SNe), we present a systematic investigation of spectral properties of Type IIb SNe (SNe IIb), Type Ib SNe (SNe Ib), and Type Ic SNe (SNe Ic). Prior studies have been based on individual objects or small samples. Here, we analyze 227 spectra of 14 SNe IIb, 258 spectra of 21 SNe Ib, and 207 spectra of 17 SNe Ic based on the stripped SN dataset of Modjaz et al. (2014) and other published spectra of individual SNe. Each SN in our sample has a secure spectroscopic ID, a date of $V$-band maximum light, and multiple spectra at different phases. We analyze these spectra as a function of subtype and phase in order to improve the SN identification scheme and constrain the progenitors of different kinds of stripped SNe. By comparing spectra of SNe IIb with those of SNe Ib, we find that the strength of H$\alpha$ can be used to quantitatively differentiate between these two subtypes at all epochs. Moreover, we find a continuum in observational properties between SNe IIb and Ib. We address the question of hidden He in SNe Ic by comparing our observations with predictions from various models that either include hidden He or in which He has been burnt. Our results favor the He-free progenitor models for SNe Ic. Finally, we construct continuum-divided average spectra as a function of subtype and phase to quantify the spectral diversity of the different types of stripped SNe., Comment: Released all code and data products on our github pages https://github.com/nyusngroup/SESNtemple and https://github.com/nyusngroup/SESNspectraLib. Accepted by ApJ. 26 pages, 17 figures, 8 Tables, Appendix. No major changes, but additions of SNe data, more references & discussion

The present study was aimed to investigate the effects of hypoxia on iron metabolism of skeletal muscle. Rat L6 skeletal muscle cells were randomly divided into three groups which were exposed to hypoxia (1% O(2)) for 0, 12, 24 h, respectively. Iron isotope tracing method was used to determine iron uptake and release. Iron content of labile iron pool (LIP) was investigated by flow cytometry, and the expressions of transferrin receptor 1 (TfR1), divalent metal transporter 1 (DMT1), ferroportin 1 (FPN1), hypoxia-inducible transcription factor-1 (HIF-1) in L6 cells were observed by Western blot. The results showed that, compared with 0-hour hypoxia group, 12-hour hypoxia group exhibited significantly increased iron uptake and LIP (P0.05), as well as decreased iron release (P0.01). Not only iron uptake and release, but also LIP in 24-hour hypoxia group were significantly decreased, compared with those in 0- and 12-hour hypoxia groups (P0.01). The expressions of HIF-1, DMT1 (IRE), DMT1 (non-IRE) and TfR1 in 12-hour hypoxia group were significantly increased compared with those in 0-hour hypoxia group (P0.01). On the contrary, the expressions of DMT1 (IRE), DMT1 (non-IRE) and FPN1 in 24-hour hypoxia group were significantly decreased compared with those in the other two groups. However, TfR1 expression in 24-hour hypoxia was higher than those in 0- and 12-hour hypoxia groups (P0.05 or P0.01). These results suggest hypoxia plays an important role in iron metabolism of skeletal muscle cells. Moderate hypoxia can increase iron uptake and decrease iron release, resulting in higher LIP, but a prolonged hypoxia induces a disordered iron metabolism of skeletal cells.

Some athletes are diagnosed as suffering from sports anemia because of iron deficiency, but the regulatory mechanism remains poorly understood. It is reported that hepcidin may provide a way to illuminate the regulatory mechanism of exercise-associated anemia. Here the authors investigate the hepcidin-involved iron absorption in exercise-associated anemia. Twelve male Wistar rats (300 ± 10 g) were randomly divided into 2 groups, 6 in a control group (CG) and 6 in an exercise group (EG, 5 wk treadmill exercise of different intensities with progressive loading). Serum samples were analyzed for circulating levels of IL-6 by means of enzyme-linked immunosorbent assay (ELISA). The expression of hepatic hepcidin mRNA was examined by real-time polymerase chain reaction analysis. The protein levels of divalent metal transporter 1 (DMT1), ferroportin1 (FPN1), and heme-carrier protein 1 (HCP1) of duodenum epithelium were examined by Western blot. The results showed that the amount of iron and ferritin in serum were lower in EG than in CG (p < .05). The levels of IL-6 and white blood cells were greater in EG than in CG (p < .01). The expression of DMT1, HCP1, and FPN1 was significantly lower in EG than in CG (p < .01). The mRNA expressions of hepatic hepcidin and hemojuvelin in skeletal muscle were remarkably higher in EG than in CG. The data indicated that inflammation was induced by strenuous exercise, and as a result, the transcriptional level of the hepatic hepcidin gene was increased, which further inhibited the expression of iron-absorption proteins and led to exercise-associated anemia.

Nitric Oxide (NO) plays an important role in iron redistribution during exercise, while its molecular regulatory mechanism is still not clear. Our present studies were to investigate the effects of NO on iron metabolism and to elucidate the regulatory mechanism of iron transport in skeletal muscle both in vivo and in vitro. One group of male Wistar rats (300 +/- 10 g) were subjected to an exercise of 30 min on a treadmill for 5 weeks (exercise group, EG, 6 rats) and the other one was placed on the treadmill without running (control group, CG, 6 rats). The cultured L6 rat skeletal muscle cells were treated with either 0.5 mM SNAP (NO donor) or not for 24 h, and their iron release and intake amount were examined by measuring radiolabelled (55)Fe. The results showed: (1) The NO content (CG, 1.09 +/- 0.18 micromol/g vs. EG, 1.49 +/- 0.17 micromol/g) and non-heme iron in gastrocnemius (CG, 118.35 +/- 11.41 microg/g vs. EG, 216.65 +/- 11.10 microg/g) of EG were significantly increased compared with CG. (2) The expression of DMT1 (IRE) and TfR1 of EG was increased. (3) The iron intake was increased in L6 cells treated with SNAP (P < 0.01). (4) Western blot results showed the protein level of both TfR1 and DMT1 (IRE) in SNAP cells were up-regulated, while the expression of FPN1 was down-regulated (P < 0.05). The data suggested that the induced elevation of NO level by exercise lead to the up-regulation of both TfR1 and DMT1 (IRE), which in turn increasing the iron absorption in skeletal muscle.

This study explores whether the Novak colorful concept map with digital teaching materials can enhance student academic achievement in learning Advanced Accounting. Four different teaching materials included conventional digital teaching materials (CDMs), Novak monotonic concept maps digital teaching materials (MCMDMs), hierarchical Novak colorful concept maps digital teaching materials (hierarchical CCMDMs) and clustered CCMDMs. Three major results were found in this study. First, the MCMDMs and CCMDMs can significantly improve student achievement than CDMs. Second, CCMDMs can significantly improve student long-term memory than MCMDMs and CDMs. Third, no significant differences exist in student achievement by using different coloring methods.