DPSCs regulate epithelial-T cell interactions in oral submucous fibrosis

BACKGROUND

Oral submucous fibrosis (OSF) is a precancerous lesion characterized by fibrous tissue deposition, the incidence of which correlates positively with the frequency of betel nut chewing. Prolonged betel nut chewing can damage the integrity of the oral mucosal epithelium, leading to chronic inflammation and local immunological derangement. However, currently, the underlying cellular events driving fibrogenesis and dysfunction are incompletely understood, such that OSF has few treatment options with limited therapeutic effectiveness. Dental pulp stem cells (DPSCs) have been recognized for their anti-inflammatory and anti-fibrosis capabilities, making them promising candidates to treat a range of immune, inflammatory, and fibrotic diseases. However, the application of DPSCs in OSF is inconclusive. Therefore, this study aimed to explore the pathogenic mechanism of OSF and, based on this, to explore new treatment options.

METHODS

A human cell atlas of oral mucosal tissues was compiled using single-cell RNA sequencing to delve into the underlying mechanisms. Epithelial cells were reclustered to observe the heterogeneity of OSF epithelial cells and their communication with immune cells. The results were validated in vitro, in clinicopathological sections, and in animal models. In vivo, the therapeutic effect and mechanism of DPSCs were characterized by histological staining, immunohistochemical staining, scanning electron microscopy, and atomic force microscopy.

RESULTS

A unique epithelial cell population, Epi1.2, with proinflammatory and profibrotic functions, was predominantly found in OSF. Epi1.2 cells also induced the fibrotic process in fibroblasts by interacting with T cells through receptor-ligand crosstalk between macrophage migration inhibitory factor (MIF)-CD74 and C-X-C motif chemokine receptor 4 (CXCR4). Furthermore, we developed OSF animal models and simulated the clinical local injection process in the rat buccal mucosa using DPSCs to assess their therapeutic impact and mechanism. In the OSF rat model, DPSCs demonstrated superior therapeutic effects compared with the positive control (glucocorticoids), including reducing collagen deposition and promoting blood vessel regeneration. DPSCs mediated immune homeostasis primarily by regulating the numbers of KRT19 + MIF + epithelial cells and via epithelial-stromal crosstalk.

CONCLUSIONS

Given the current ambiguity surrounding the cause of OSF and the limited treatment options available, our study reveals that epithelial cells and their crosstalk with T cells play an important role in the mechanism of OSF and suggests the therapeutic promise of DPSCs.

A gB nanoparticle vaccine elicits a protective neutralizing antibody response against EBV

Epstein-Barr virus (EBV) is a global public health concern, as it is known to cause multiple diseases while also being etiologically associated with a wide range of epithelial and lymphoid malignancies. Currently, there is no available prophylactic vaccine against EBV. gB is the EBV fusion protein that mediates viral membrane fusion and participates in host recognition, making it critical for EBV infection in both B cells and epithelial cells. Here, we present a gB nanoparticle, gB-I53-50 NP, that displays multiple copies of gB. Compared with the gB trimer, gB-I53-50 NP shows improved structural integrity and stability, as well as enhanced immunogenicity in mice and non-human primate (NHP) preclinical models. Immunization and passive transfer demonstrate a robust and durable protective antibody response that protects humanized mice against lethal EBV challenge. This vaccine candidate demonstrates significant potential in preventing EBV infection, providing a possible platform for developing prophylactic vaccines for EBV.

Catalpol Prevents Glomerular Angiogenesis Induced by Advanced Glycation End Products via Inhibiting Galectin-3

OBJECTIVE

The main characteristics of diabetic nephropathy (DN) at the early stage are abnormal angiogenesis of glomerular endothelial cells (GECs) and macrophage infiltration. Galectin-3 plays a pivotal role in the pathogenesis of DN via binding with its ligand, advanced glycation end products (AGEs). Catalpol, an iridoid glucoside extracted from Rehmannia glutinosa, has been found to ameliorate vascular inflammation, reduce endothelial permeability, and protect against endothelial damage in diabetic milieu. However, little is known about whether catalpol could exert an anti-angiogenesis and anti-inflammation effect induced by AGEs.

METHODS

Mouse GECs (mGECs) and RAW 264.7 macrophages were treated with different concentrations of AGEs (0, 50, 100, 200 and 400 µg/mL) for different time (0, 6, 12, 24 and 48 h) to determine the optimal concentration of AGEs and treatment time. Cells were treated with catalpol (10 µmol/L), GB1107 (1 µmol/L, galectin-3 inhibitor), PX-478 (50 µmol/L, HIF-1α inhibitor), adenovirus-green fluorescent protein (Ad-GFP) [3×107 plaque-forming unit (PFU)/mL] or Ad-galectin-3-GFP (2×108 PFU/mL), which was followed by incubation with 50 µg/mL AGEs. The levels of galectin-3, vascular endothelial growth factor A (VEGFA) and pro-angiogenic factors angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), tunica interna endothelial cell kinase-2 (Tie-2) were detected by enzymelinked immunosorbent assay (ELISA). Cell counting kit-8 (CCK-8) assay was used to evaluate the proliferation of these cells. The expression levels of galectin-3, vascular endothelial growth factor receptor 1 (VEGFR1), VEGFR2, and hypoxia-inducible factor-1α (HIF-1α) in mGECs and those of galectin-3 and HIF-1α in RAW 264.7 macrophages were detected by Western blotting and immunofluorescence (IF) staining. The rat DN model was established. Catalpol (100 mg/kg) or GB1107 (10 mg/kg) was administered intragastrically once a day for 12 weeks. Ad-galectin-3-GFP (6×107 PFU/mL, 0.5 mL) or Ad-GFP (6×106 PFU/mL, 0.5 mL) was injected into the tail vein of rats 48 h before the sacrifice of the animals. The expression of galectin-3, VEGFR1, VEGFR2, and HIF-1α in renal cortices was analyzed by Western blotting. The expression of galectin-3, F4/80 (a macrophage biomarker), and CD34 (an endothelium biomarker) in renal cortices was detected by IF staining, and collagen accumulation by Masson staining.

RESULTS

The expression levels of galectin-3 and VEGFA were significantly higher in mGECs and RAW 264.7 macrophages treated with 50 µg/mL AGEs for 48 h than those in untreated cells. Catalpol and GB1107 could block the AGEs-induced proliferation of mGECs and RAW 264.7 macrophages. Over-expression of galectin-3 was found to reduce the inhibitory effect of catalpol on the proliferation of cells. Catalpol could significantly decrease the levels of Ang-1, Ang-2 and Tie-2 released by AGEs-treated mGECs, which could be reversed by over-expression of galectin-3. Catalpol could significantly inhibit AGEs-induced expression of galectin-3, HIF-1α, VEGFR1, and VEGFR2 in mGECs. The inhibitory effect of catalpol on galectin-3 in AGEs-treated mGECs was impaired by PX-478. Moreover, catalpol attenuated the AGEs-activated HIF-1α/galectin-3 pathway in RAW 264.7 macrophages, which was weakened by PX-478. Additionally, catalpol significantly inhibited the expression of galectin-3, macrophage infiltration, collagen accumulation, and angiogenesis in the kidney of diabetic rats. Over-expression of galectin-3 could antagonize these inhibitory effects of catalpol.

CONCLUSION

Catalpol prevented the angiogenesis of mGECs and macrophage proliferation via inhibiting galectin-3. It could prevent the progression of diabetes-induced renal damage.

[Application of entropy weight TOPSIS comprehensive method in the evaluation of students' physical health level]

Objective: To comprehensively evaluate the physical health level of students of different school-age segments in four regions of Anhui province using the entropy weight approximation ideal solution ranking method (TOPSIS), and to provide a scientific method and basis for conducting school health work evaluation. Methods: Using the physical fitness survey data of four regions in Anhui province, the entropy weight method was used to draw the weights of various indicators for different school-age segments of men and women. Then, the TOPSIS method was used to evaluate the school-age segments of men and women in the four regions. Finally, the physical health level of students in four regions was classified according to the results of entropy weight TOPSIS and the rank sum ratio method. Results: A total of 10 127 students were included in this study, with an average age of (11.85±3.82) years, including 5 050 males (49.8%) and 5 072 urban students (50.1%). The results of the entropy weight method showed that the weight of body mass index of boys was similar to that of girls in each school-age segment. According to the TOPSIS and rank sum ratio analysis, the physical health level of students in the four regions of Anhui province was different. The physical health score of Suzhou was 0.617 4 points, which was classified as the best grade. The scores of Hefei and Wuhu were 0.556 3 and 0.411 2, which were classified as middle. Jiju City scored 0.381 9 points, which was classified as poor. Conclusion: TOPSIS combined with rank sum ratio can reflect the level of students' physical health, which can be applied to the evaluation of students' physical health and provide a basis for monitoring students' physical health.

Maternal high fat diet multigenerationally programs HPA function and behaviors in male rat offspring

Maternal environmental factors have been demonstrated to exert significant influences on the health of offspring. The hypothalamic-pituitary-adrenal (HPA) axis is an important neuroendocrine stress system that can be influenced by early-life challenges. Our previous research has revealed that the consumption of a high-fat diet (HFD) by pregnant and lactating rats leads to the programming of HPA axis activity in male offspring of the first generation (referred to as F1HFD/C). The present study aimed to investigate whether the observed remodeling of the HPA axis could be inherited by second-generation male offspring (referred to as F2HFD/C), following maternal HFD exposure. The results showed that F2HFD/C rats exhibited enhanced basal HPA axis activity, similar to their F1HFD/C ancestors. Moreover, F2HFD/C rats displayed exacerbated corticosterone responses to restraint and lipopolysaccharide-induced stress, but not to insulin-induced hypoglycemia stress. Furthermore, maternal HFD exposure significantly aggravated depression-like behavior in the F2 generation subjected to chronic unpredictable mild stress. To investigate the role of central CGRP signaling in maternal diet-induced programming of the HPA axis across generations, we conducted central infusion of αCGRP8-37, a CGRP receptor antagonist, in F2HFD/C rats. The results demonstrated that αCGRP8-37, attenuated depression-like behaviors and reduced the hyperresponsiveness of the HPA axis to restraint stress in these rats. Therefore, central CGRP signaling may contribute to maternal diet-induced programming of HPA axis across generations. In conclusion, our study provides evidence that maternal HFD consumption can lead to multigenerational programming of the HPA axis and behaviors in adult male descendants.

Strain Effects in Twisted Spiral Antimonene

Van der Waals (vdW) layered materials exhibit fruitful novel physical properties. The energy band of such materials depends strongly on their structures, and a tremendous variation in their physical properties can be deduced from a tiny change in inter-layer spacing, twist angle, or in-plane strain. In this work, a kind of vdW layered material of spiral antimonene is constructed, and the strain effects in the material are studied. The spiral antimonene is grown on a germanium (Ge) substrate and is induced by a helical dislocation penetrating through few atomic-layers of antimonene (β-phase). The as-grown spiral is intrinsically strained, and the lattice distortion is found to be pinned around the dislocation. Both spontaneous inter-layer twist and in-plane anisotropic strain are observed in scanning tunneling microscope (STM) measurements. The strain in the spiral antimonene can be significantly modified by STM tip interaction, leading to a variation in the surface electronic density of states (DOS) and a large modification in the work function of up to a few hundreds of millielectron-volts (meV). Those strain effects are expected to have potential applications in building up novel piezoelectric devices.

Proposal for Detection of the 0^{'} and π^{'} Phases in Quantum-Dot Josephson Junctions

The competition between the Kondo correlation and superconductivity in quantum-dot Josephson junctions (QDJJs) has been known to drive a quantum phase transition between 0 and π junctions. Theoretical studies so far have predicted that under strong Coulomb correlations the 0-π transition should go through intermediate states, 0^{'} and π^{'} phases. By combining a nonperturbative numerical method and the resistively shunted junction model, we investigated the magnetic-field-driven phase transition of the QDJJs in the Kondo regime and found that the low-field magnetotransport exhibits a unique feature which can be used to distinguish the intermediate phases. In particular, the magnetic-field driven π^{'}-π transition is found to lead to the enhancement of the supercurrent which is strongly related to the Kondo effect.

Charge detection of a quantum dot under different tunneling barrier symmetries and bias voltages

We report the realization of a coupled quantum dot (QD) system containing two single QDs made in two adjacent InAs nanowires. One QD (sensor QD) was used as a charge sensor to detect the charge state transitions in the other QD (target QD). We investigated the effect of the tunneling barrier asymmetry of the target QD on the detection visibility of the charge state transitions in the target QD. The charge stability diagrams of the target QD under different configurations of barrier-gate voltages were simultaneously measured via the direct signals of electron transport through the target QD and via the detection signals of the charge state transitions in the target QD revealed by the sensor QD. We find that the complete Coulomb diamond boundaries of the target QD and the transport processes involving the excited states in the target QD can be observed in the transconductance signals of the sensor QD only when the tunneling barriers of the target QD are nearly symmetric. These observations were explained by analyzing the effect of the ratio of the two tunneling rates on the electron transport processes through the target QD. Our results imply that it is important to consider the symmetry of the tunnel couplings when constructing a charge sensor integrated QD device.

Electrically tunable spin-orbit interaction in an InAs nanosheet

We report an experimental study of the spin-orbit interaction (SOI) in an epitaxially grown free-standing InAs nanosheet in a dual-gate field-effect device. Gate-transfer characteristic measurements show that independent tuning of the carrier density in the nanosheet and the potential difference across the nanosheet can be efficiently achieved with the use of a dual gate. The quantum transport characteristics of the InAs nanosheet are investigated by magnetoconductance measurements at low temperatures. It is shown that the electron transport in the nanosheet can be tuned from the weak antilocalization to the weak localization and then back to the weak antilocalization regime with a voltage applied over the dual gate without a change in the carrier density. The spin-orbit length extracted from the magnetoconductance measurements at a constant carrier density exhibits a peak value at which the SOI of the Rashba type is suppressed and the spin relaxation due to the presence of an SOI of the Dresselhaus type in the nanosheet can be revealed. Energy band diagram simulations have also been carried out for the device under the experimental conditions and the physical insights into the experimental observations have been discussed in light of the results of simulations.

Oleanolic acid combined with olaparib enhances radiosensitization in triple negative breast cancer and hypoxia imaging with 18F-FETNIM micro PET/CT

The heterogeneity of triple negative breast cancer (TNBC) results in the worst prognosis among breast cancer types, making its treatment strategy very challenging. A recent study showed that oleanolic acid (OA) has a radiosensitizing effect on tumor cells, but it does not show a good clinical effect when used alone in radiotherapy. The cytotoxicity of radiotherapy can be enhanced by modulating DNA repair, so new treatment options are being investigated to inhibit DNA repair pathways and sensitize tumors to radiation. Radiation induces DNA double-strand breaks (DSBs), and inhibition of Poly (ADP-Ribose) polymerase (PARP) can prevent the repair of these lesions. Hence, we evaluated the radiosensitization and the underlying mechanism of combination treatment with OA and olaparib in TNBC. Meanwhile, tumor hypoxia was monitored with ¹⁸F-Fluoroerythronitroimidazole (FETNIM) positron emission tomography/computed tomography (PET/CT) during radiosensitization therapy. Here, we found that OA and olaparib in combination with radiotherapy significantly inhibited cell proliferation compared with other groups. The results were observed using colony formation assays [sensitization enhancement ratios (SER) 1.16-1.65]. In vivo, tumor growth was significantly delayed in transplanted tumors receiving irradiation (IR) with OA and olaparib. ¹⁸F-FETNIM PET/CT can be utilized for tumor hypoxia monitoring and radiosensitization response evaluation. In conclusion, these results suggest that the combination of OA and olaparib with IR enhances the inhibition of MDA-MB-231 in cell culture and in mice, providing a potentially novel combination for the effective treatment of TNBC patients.

Quasiparticle Trapping at Vortices Producing Josephson Supercurrent Enhancement

The Josephson junction of a strong spin-orbit material under a magnetic field is a promising Majorana fermion candidate. Supercurrent enhancement by a magnetic field has been observed in the InAs nanowire Josephson junctions and assigned to a topological transition. In this work we observe a similar phenomenon but discuss the nontopological origin by considering the trapping of quasiparticles by vortices that penetrate the superconductor under a finite magnetic field. This assignment is supported by the observed hysteresis of the switching current when sweeping up and down the magnetic field. Our experiment shows the importance of quasiparticles in superconducting devices with a magnetic field, which can provide important insights for the design of qubits using superconductors.

Fabrication and characterization of InSb nanosheet/hBN/graphite heterostructure devices

Semiconductor InSb nanosheet/hexagonal boron nitride (hBN)/graphite trilayers are fabricated, and single- and double-gate devices made from the trilayers are realized and characterized. The InSb nanosheets employed in the trilayer devices are epitaxially grown, free-standing, zincblende crystals and are in micrometer lateral sizes. The hBN and graphite flakes are obtained by exfoliation. Each trilayer is made by successively stacking an InSb nanosheet on an hBN flake and on a graphite flake using a home-made alignment stacking/transfer setup. The fabricated single- and double-gate devices are characterized by electrical and/or magnetotransport measurements. In all these devices, the graphite and hBN flakes are employed as the bottom gates and the gate dielectrics. The measurements of a fabricated single bottom-gate field-effect device show that the InSb nanosheet in the device has an electron field-effect mobility of ∼7300 cm²V^-1s^-1and a low gate hysteresis of ∼0.05 V at 1.9 K. The measurements of a double-gate Hall-bar device show that both the top and the bottom gate exhibit strong capacitive couplings to the InSb nanosheet channel and can thus tune the nanosheet channel conduction effectively. The electron Hall mobility in the InSb nanosheet of the Hall-bar device is extracted to be larger than 1.1 × 10⁴cm²V^-1s^-1at a sheet electron density of ∼6.1 × 10¹¹cm^-2and 1.9 K and, thus, the device exhibits well-defined Shubnikov-de Haas oscillations.

Surface-bulk coupling in a Bi2Te3 nanoplate grown by van der Waals epitaxy

We report an experimental study of the effect of coherent surface-bulk electron scattering on quantum transport in a three-dimensional topological insulator Bi₂Te₃ nanoplate. The nanoplate is grown via van der Waals epitaxy on a mica substrate and a top-gated Hall-bar device is fabricated from the nanoplate directly on the growth substrate. Top-gate voltage dependent measurements of the sheet resistance of the device reveal that the transport carriers in the nanoplate are of n-type and that, with decreasing top gate voltage, the carrier density in the nanoplate is decreased. However, the mobility is increased with decreasing top-gate voltage. This mobility increase with decreasing carrier density in the nanoplate is demonstrated to arise from a decrease in bulk-to-surface electron scattering rate. Low-field magnetotransport measurements are performed at low temperatures. The measured magnetoconductivity of the nanoplate shows typical weak anti-localization (WAL) characteristics. We analyze the measurements by taking surface-bulk inter-channel electron scattering into account and extract dephasing times τ_φ, diffusion coefficients D of electrons at the top surface and in the bulk, and the surface-bulk scattering times τ_SB as a function of top-gate voltage and temperature. It is found that the dephasing in the nanoplate arises dominantly from electron-electron scattering with small energy transfers. It is also found that the ratio of τ_φ/τ_SB (a measure of the surface-bulk electron coherent coupling) is decreased with decreasing gate voltage or increasing temperature. We demonstrate that taking the surface-bulk coherent electron scattering in our Bi₂Te₃ nanoplate into account is essential to understand quantum transport measurements at low temperatures.

[New understanding and research opportunities of metabolically healthy obesity]

The paradox of obesity and metabolically healthy obesity are being challenged. More and more studies have disputed the potential mechanism and prognostic value of metabolically healthy obesity. The study of metabolically healthy obesity is helpful to clarify the potential causes of obesity paradox and the potential mechanism of different degrees of obesity harm to the population. From the perspective of evidence-based medicine, combined with the relevant literature at home and abroad, this study reviewed the new understanding of metabolically healthy obesity, lifestyle factors, the impact of fat factors on metabolically healthy obesity, and the new opportunities of metabolically healthy obesity research, in order to explore whether metabolically healthy obesity can maintain and gradually reduce weight for a long time, so as to improve cardiovascular disease In order to achieve the purpose of primary prevention of related diseases.

Eslicarbazepine acetate add-on therapy for drug-resistant focal epilepsy

BACKGROUND

This is an update of a review first published in 2011, and last updated in 2017. Most people with epilepsy have a good prognosis, but up to 30% of people continue to have seizures despite several regimens of antiepileptic drugs. In this review, we summarized the current evidence regarding eslicarbazepine acetate (ESL) when used as an add-on treatment for drug-resistant focal epilepsy.

OBJECTIVES

To evaluate the efficacy and tolerability of ESL when used as an add-on treatment for people with drug-resistant focal epilepsy.

SEARCH METHODS

For this update, we searched the following databases on 10 September 2020: Cochrane Register of Studies (CRS Web) and MEDLINE (Ovid). CRS Web includes randomized or quasi-randomized, controlled trials from Specialized Registers of Cochrane Review Groups including Epilepsy, CENTRAL, PubMed, Embase, ClinicalTrials.gov and the WHO ICTRP. There were no language restrictions. We reviewed the reference lists of retrieved studies and contacted the manufacturers of ESL and experts in the field for information about any unpublished or ongoing studies.

SELECTION CRITERIA

Randomized placebo-controlled double-blind add-on trials of ESL in people with drug-resistant focal epilepsy.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion and extracted data. Outcomes investigated included 50% or greater reduction in seizure frequency, seizure freedom, treatment withdrawal, adverse effects and drug interactions. Primary analyses were by intention to treat (ITT). The dose-response relationship was evaluated in regression models.

MAIN RESULTS

We included seven trials (2185 participants, aged 2 to 77 years), which were at low or unclear risk of bias apart from a high risk of attrition bias; all studies were funded by the pharmaceutical company, BIAL. The overall risk ratio (RR) for 50% or greater reduction in seizure frequency was 1.57 (95% confidence interval (CI) 1.34 to 1.83). For adults, the RR was 1.71 (95% CI 1.42 to 2.05; 5 studies, 1799 participants; moderate-certainty evidence); for children aged six to 18 years, the RR was 1.35 (95% CI 0.98 to 1.87; 2 studies, 322 participants; moderate-certainty evidence). Dose regression analysis showed evidence that ESL reduced seizure frequency with an increase in efficacy with increasing doses of ESL. ESL was associated with seizure freedom (RR 3.16, 95% CI 1.73 to 5.78; 6 studies, 1922 participants; moderate-certainty evidence). Participants were more likely to have ESL withdrawn for adverse effects (RR 2.72, 95% CI 1.66 to 4.46; 7 studies, 2185 participants; moderate-certainty evidence), but not for any reason (RR 1.25, 95% CI 0.93 to 1.70; 7 studies, 2185 participants; moderate-certainty evidence). The following adverse effects were associated with ESL: dizziness (RR 2.77, 99% CI 1.85 to 4.15); nausea (RR 2.55, 99% CI 1.39 to 4.67); somnolence (RR 1.75, 99% CI 1.18 to 2.61); diplopia (RR 4.07, 99% CI 1.86 to 8.89); and vomiting (RR 2.37, 99% CI 1.19 to 4.74). Overall, the certainty of the evidence was moderate due to a high discontinuation rate in studies of adults.

AUTHORS' CONCLUSIONS

ESL reduces seizure frequency when used as an add-on treatment for adults with drug-resistant focal epilepsy. The trials included in this review were of short-term duration. In addition, this update found that ESL may reduce seizure frequency in children from 6 to 18 years of age; however the results are inconclusive.

A highly tunable quadruple quantum dot in a narrow bandgap semiconductor InAs nanowire

Quantum dots (QDs) made from semiconductors are among the most promising platforms for the development of quantum computing and simulation chips, and they have the advantages of high density integration and compatibility with the standard semiconductor chip fabrication technology compared to other platforms. However, the development of a highly tunable semiconductor multiple QD system still remains a major challenge. Here, we demonstrate the realization of a highly tunable linear quadruple QD (QQD) in a narrow bandgap semiconductor InAs nanowire via a fine finger gate technique. The QQD is studied by electron transport measurements in the linear response regime. Characteristic two-dimensional charge stability diagrams containing four groups of resonant current lines of different slopes are obtained for the QQD. It is shown that these current lines arise from and can be individually assigned to resonant electron transport through the energy levels of different QDs. Benefitting from the excellent gate tunability, we also demonstrate the tuning of the QQD to regimes where the energy levels of two QDs, three QDs and all four QDs are energetically in resonance, respectively, with the Fermi level of the source and drain contacts. A capacitance network model is developed for the linear QQD and the simulated charge stability diagrams based on this model show good agreement with the experiments. Our work provides solid experimental evidence that narrow bandgap semiconductor nanowire multiple QDs could be used as a versatile platform to achieve integrated qubits for quantum computing and to perform quantum simulations of complex many-body systems.

A charge sensor integration to tunable double quantum dots on two neighboring InAs nanowires

A single quantum dot serving as a charge sensor is integrated to scalable double quantum dots using local top finger-gate techniques on two neighboring pure-phase InAs nanowires. The single dot built on one nanowire capacitively couples one of the double dots constructed on another nanowire via a metal bridge gate. The charge occupation states of double quantum dots can be accurately monitored by the sensor even in a few-electron regime in which transport tunneling current through the double dots vanishes. In the tunneling spectroscopy of double dots, electron inter dot tunneling process is absent; however, it can be illustrated by the sensor in terms of a transconductance line between the two closest triple points. Thus, tunnel coupling strength between the double dots is quantitatively extracted from the detectable charge transition. The highly tunable multiple quantum dots with integrated charge sensors on InAs nanowires could be an essential building block for quantum information processing technology.

Measurements of anisotropic g-factors for electrons in InSb nanowire quantum dots

We have measured the Zeeman splitting of quantum levels in few-electron quantum dots (QDs) formed in narrow bandgap InSb nanowires via the Schottky barriers at the contacts under application of different spatially orientated magnetic fields. The effective g-factor tensor extracted from the measurements is strongly anisotropic and level-dependent, which can be attributed to the presence of strong spin-orbit interaction (SOI) and asymmetric quantum confinement potentials in the QDs. We have demonstrated a successful determination of the principal values and the principal axis orientations of the g-factor tensors in an InSb nanowire QD by the measurements under rotations of a magnetic field in the three orthogonal planes. We also examine the magnetic field evolution of the excitation spectra in an InSb nanowire QD and extract a SOI strength of [Formula: see text] ∼ 180 μeV from an avoided level crossing between a ground state and its neighboring first excited state in the QD.

Loganin alleviates macrophage infiltration and activation by inhibiting the MCP-1/CCR2 axis in diabetic nephropathy

BACKGROUND/AIMS

The theory of inflammation is one of the important theories in the pathogenesis of diabetic nephropathy (DN). We herein aimed to explore whether loganin affected macrophage infiltration and activation upon diabetic nephropathy (DN) by a spontaneous DN mice and a co-culture system of glomerular mesangial cells (GMCs) and macrophage cells (RAW264.7) which was induced by advanced glycation end products (AGEs).

METHODS AND KEY FINDINGS

Loganin showed remarkable capacity on protecting renal from damage by mitigating diabetic symptoms, improving the histomorphology of the kidney, decreasing the expression of extracellular matrix such as FN, COL-IV and TGF-β, reversing the production of IL-12 and IL-10 and decreasing the number of infiltrating macrophages in the kidney. Moreover, loganin showed markedly effects by suppressing iNOS and CD16/32 expressions (M1 markers), increasing Arg-1 and CD206 expressions (M2 markers), which were the phenotypic transformation of macrophage. These effects may be attributed to the inhibition of the receptor for AGEs (RAGE) /monocyte chemotactic protein-1 (MCP-1)/CC chemokine receptor 2 (CCR2) signaling pathway, with significantly down-regulated expressions of RAGE, MCP-1 and CCR2 by loganin. Loganin further decreased MCP-1 secretion when RAGE was silenced, which means other target was involved in regulating the MCP-1 expression. While loganin combinated with the inhibitor of CCR2 exerted stronger anti-inhibition effects of iNOS expression, suggesting that CCR2 was the target of loganin in regulating the activation of macrophages.

SIGNIFICANCE

Loganin could ameliorate DN kidney damage by inhibiting macrophage infiltration and activation via the MCP-1/CCR2 signaling pathway in DN.

[Effect of aspirin on hepatocellular carcinoma and its related mechanism]

Aspirin, as a traditional non-steroidal anti-inflammatory drug, has therapeutic and preventive effects on gastrointestinal tumors. Hepatocellular carcinoma is one of the most common malignant tumors in the digestive tract, so it is necessary to find effective preventive and therapeutic measures. This article reviews the research progress and mechanism of aspirin on hepatocellular carcinoma with a view to provide references for future clinical treatment.

Ambipolar transport in narrow bandgap semiconductor InSb nanowires

We report on a transport measurement study of top-gated field effect transistors made out of InSb nanowires grown by chemical vapor deposition. The transistors exhibit ambipolar transport characteristics revealed by three distinguished gate-voltage regions: In the middle region where the Fermi level resides within the bandgap, the electrical resistance shows an exponential dependence on temperature and gate voltage. With either more positive or negative gate voltages, the devices enter the electron and hole transport regimes, revealed by the resistance decreasing linearly with decreasing temperature. From the transport measurement data of a 1 μm-long device made from a nanowire of 50 nm in diameter, we extracted a bandgap energy of 190-220 meV. The off-state current of this device is found to be suppressed within the measurement noise at a temperature of T = 4 K. A shorter, 260 nm-long device is found to exhibit a finite off-state current and a circumference-normalized on-state hole current of 11 μA μm^-1 at V_D = 50 mV which is the highest for such a device to our knowledge. The ambipolar transport characteristics make the InSb nanowires attractive for CMOS electronics, hybrid electron-hole quantum systems and hole based spin qubits.

[Interaction of health literacy and second-hand smoke exposure on psychopathological symptoms of middle school students]

Objective: To explore the interaction of health literacy and second-hand smoke exposure on psychopathological symptoms of middle school students. Methods: From November 2015 to January 2016, 22 628 middle school students from Shenyang of Liaoning Province, Bengbu of Anhui Province, Xinxiang of Henan Province, Ulanqab of Inner Mongolia Autonomous Region, Chongqing Municipality, and Yangjiang of Guangdong Province were enrolled by using the multi-stage cluster convenience sampling method. A questionnaire was used to collect the data including demographic information, health literacy, second-hand smoke exposure, and psychopathological symptoms. A multivariate logistic regression model was used to analyze the interaction of health literacy and second-hand smoke exposure on psychopathological symptoms of middle school students. Results: The age of students was (15.36±1.79) years old, of which 10 990 were boys, accounting for 48.6% of total students. The detection rate of psychopathological symptoms was 29.1% (6 581/22 628). The detection rate of psychopathological symptoms in those who were exposed to second-hand smoke was 38.1% (2 401/6 304), which was higher than that in the non-second-hand smoke exposure group [25.6% (4 180/16 324)] (P<0.001). The OR (95%CI) of the interaction between medium and low levels of overall health literacy, low level of interpersonal dimension of health literacy and second-hand smoke exposure was 1.19 (1.15-1.24), 2.00 (1.92-2.10) and 1.59 (1.52-1.66), respectively. Conclusion: There was a positive interaction between middle and low levels of overall health literacy, low level of interpersonal dimension of health literacy and second-hand smoke exposure on psychopathological symptoms of middle school students.

Revealing misfit dislocations in InAs x P1-x -InP core-shell nanowires by x-ray diffraction

InAs _x P_1-x nanowires are promising building blocks for future optoelectronic devices and nanoelectronics. Their structure may vary from nanowire to nanowire, which may influence their average optoelectronic properties. Therefore, it is highly important for their applications to know the average properties of an ensemble of the nanowires. Structural properties of the InAs _x P_1-x -InP core-shell nanowires were investigated using the coplanar x-ray diffraction performed at a synchrotron facility. Studies of series of symmetric and asymmetric x-ray Bragg reflections allowed us to determine the 26% ± 3% of As chemical composition in the InAs _x P_1-x core, core-shell relaxation, and the average tilt of the nanowires with respect to the substrate normal. Based on the x-ray diffraction, scanning, and transmission electron microscopy measurements, a model of the core-shell relaxation was proposed. Partial relaxation of the core was attributed to misfit dislocations formed at the core-shell interface and their linear density was estimated to be 3.3 ± 0.3 × 10⁴ cm^-1.

[Association of health literacy and smoking behaviors among middle school students in six cities of China]

Objective: To explore the association between the health literacy (HL) and smoking behaviors in middle school students. Methods: From November 2015 to January 2016, middle school students in Shenyang City of Liaoning Province, Bengbu City of Anhui Province, Xinxiang City of Henan Province, Ulanqab City of Inner Mongolia Autonomous Region, Chongqing City and Yangjiang City of Guangdong Province were enrolled by using a multistage stratified cluster sampling method. A total of 23 137 questionnaires were issued and 22 628 questionnaires were valid. A questionnaire survey was conducted to collect demographic information, HL and smoking behaviors. The low, middle, and high-level group were classified according to the tertile of HL score. A multiple logistic regression model was conducted to explore the association between the HL and smoking behaviors. Results: The age of subjects was (15.4±1.8) years old, and HL score was (104.1±18.7) points. The proportion of former smoking, recent smoking and passive smoking was 9.2% (2 071), 2.8% (635) and 27.9% (6 304), respectively. The proportion of former smokers who tried to quit smoking was 50.1% (1 037/2 071). Compared to the high-level HL, the low-level HL increased the risk of former smoking [OR (95%CI): 1.85 (1.61-2.13)], recent smoking [OR (95%CI): 1.68 (1.33-2.14)] and passive smoking [OR (95%CI): 1.34 (1.23-1.46)], and decreased the likelihood of smoking cessation [OR (95%CI): 0.70 (0.53-0.92)], after adjusting for the gender, school type, registered residence, household structure, accommodation type, educational level of patients, and self-reported family economic status. Conclusion: The HL of middle school students was related to their smoking behaviors.

[Surveillance of potential transmission factors of schistosomiasis in Xiuzhou District of Jiaxing City from 2013 to 2015]

OBJECTIVE

To understand the potential risk of schistosomiasis transmission in Xiuzhou District of Jiaxing City, so as to provide the scientific evidence for consolidating schistosomiasis control achievements.

METHODS

Fixed and mobile surveillance sites were set up in Xiuzhou District of Jiaxing City from 2013 to 2015. Oncomelania hupensis snails was surveyed historical snail habitats, current snail habitats, and suspected snail habitats. The schistosome infections were identified using serological and parasitological testing among local residents and mobile populations. In addition, the survival and reproduction of snails imported into Xiuzhou District was observed, and the schistosome infection in wild reservoir hosts was detected.

RESULTS

A total of 540.14 hm² of settings were surveyed in Xiuzhou District, Jiaxing City from 2013 to 2015, and 1.65 hm² of snail habitats were identified. The snail habitats were mainly located in dry lands, and no infected snails or importation of snails were found. During the period from 2013 to 2015, a total of 7 668 local residents and mobile populations were examined in Xiuzhou District, and no new local infections were detected; however, three imported schistosomiasis cases were identified. Field simulation experiment showed that the imported snails laid eggs and reproduced in Xiuzhou District, and no schistosome infections were found in wild animals.

CONCLUSIONS

There are still residual Oncomelania snails and imported schistosomiasis patients in Xiuzhou District of Jiaxing City; therefore, the surveillance and management of local Oncomelania snails and imported schistosomiasis should be intensified to reduce the risk of schistosomiasis transmission.

Universal conductance fluctuations and phase-coherent transport in a semiconductor Bi2O2Se nanoplate with strong spin-orbit interaction

We report on phase-coherent transport studies of a Bi2O2Se nanoplate and on observation of universal conductance fluctuations and spin-orbit interaction induced reduction in fluctuation amplitude in the nanoplate. Thin-layered Bi2O2Se nanoplates are grown by chemical vapor deposition (CVD) and transport measurements are made on a Hall-bar device fabricated from a CVD-grown nanoplate. The measurements show weak antilocalization at low magnetic fields at low temperatures, as a result of spin-orbit interaction, and a crossover toward weak localization with increasing temperature. Temperature dependences of characteristic transport lengths, such as spin relaxation length, phase coherence length, and mean free path, are extracted from the low-field measurement data. Universal conductance fluctuations are visible in the low-temperature magnetoconductance over a large range of magnetic fields and the phase coherence length extracted from the autocorrelation function is consistent with the result obtained from the weak localization analysis. More importantly, we find a strong reduction in amplitude of the universal conductance fluctuations and show that the results agree with the analysis assuming strong spin-orbit interaction in the Bi2O2Se nanoplate.

Reliability and validity of the Chinese version of the Patient Health Questionnaire 9 (C-PHQ-9) in patients with epilepsy

OBJECTIVE

The aim of this study was to evaluate the clinical reliability and validity of the Chinese version of the Patient Health Questionnaire 9 (C-PHQ-9) in patients with epilepsy.

METHODS

A total of 213 consecutive adult patients with epilepsy were evaluated. Receiver operating characteristic (ROC) analysis was performed using C-PHQ-9 and Chinese version of Patient Health Questionnaire 2 (C-PHQ-2) as predictors and the Mini International Neuropsychiatric Interview Plus Version 5.0.0 as the gold standard.

RESULTS

The C-PHQ-9 was easily understood and quickly finished by the patients. According to the gold standard, the prevalence of current major depressive disorder in this population was 16.4%. Cronbach's α coefficient for the C-PHQ-9 was 0.860. The ROC analysis showed an area under the curve (AUC) of 0.888 (95% confidence interval [CI] = 0.838-0.927). At a cutoff score of >6, the C-PHQ-9 had a sensitivity of 82.86%, a specificity of 84.27%, a positive predictive value of 50.9%, and a negative predictive value of 96.2%. The C-PHQ-2 at a cutoff score of >1 resulted in the greatest balance of sensitivity and specificity (77.14% and 75.28%, respectively).

CONCLUSION

Our findings support a high reliability and validity for the C-PHQ-9 as a screening tool for the detection of current major depression in Chinese patients with epilepsy.

Synergistic protection of tetramethylpyrazine phosphate and borneol on brain microvascular endothelium cells injured by hypoxia

The combination of tetramethylpyrazine phosphate (TMPP) and borneol (BO) protects against cerebral ischemia. However, the mechanism for their synergistic effect is unclear. In this study, an oxygen-glucose deprivation (OGD) injured brain model was induced in microvascular endothelium cells (BMECs). TMPP and BO concentrations were optimized according to an MTT assay. Cells were divided into five groups: control, model, TMPP, BO, and TMPP+BO. Subsequently, oxidative stress was evaluated based on the levels of superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), glutathione peroxidase (GSH-Px), and reactive oxygen species (ROS). Intracellular calcium ([Ca²⁺]i) was detected using a laser confocal microscope. Cellular apoptosis was examined via Hoechst 33342 staining, flow cytometry, and expression of p53, B-cell lymphoma 2 (BCL-2), BCL-2-like protein 4 (BAX), and caspase-3 mRNA. Angiogenesis was evaluated based on expression of basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), fibroblast growth factor receptor 1 (FGFR1), Vascular endothelial growth factor receptor 1 (VEGFR1), and VEGFR2. Results showed that 5.0 μM TMPP and 0.5 μM BO were optimal. Monotherapy significantly enhanced CAT, BCL-2, and VEGF, and also reduced [Ca²⁺]i, apoptosis, and BAX. TMPP increased SOD, GSH-Px, and bFGF, and reduced MDA, ROS, p53, and caspase-3 levels. BO reduced VEGFR1 expression. TMPP+BO combination exhibited synergistic effects in decreasing apoptosis, and modulating expression of BCL-2, BAX, and VEGFR1. These results indicate that protection of OGD-injured BMECs by TMPP+BO combination involves anti-oxidation, apoptosis inhibition, and angiogenesis. Moreover, their synergistic mechanism was mainly related to the regulation of apoptosis and angiogenesis.

Measurements of Strain and Bandgap of Coherently Epitaxially Grown Wurtzite InAsP-InP Core-Shell Nanowires

We report on experimental determination of the strain and bandgap of InAsP in epitaxially grown InAsP-InP core-shell nanowires. The core-shell nanowires are grown via metal-organic vapor phase epitaxy. The as-grown nanowires are characterized by transmission electron microscopy, X-ray diffraction, micro-photoluminescence (μPL) spectroscopy, and micro-Raman (μ-Raman) spectroscopy measurements. We observe that the core-shell nanowires are of wurtzite (WZ) crystal phase and are coherently strained with the core and the shell having the same number of atomic planes in each nanowire. We determine the predominantly uniaxial strains formed in the core-shell nanowires along the nanowire growth axis and demonstrate that the strains can be described using an analytical expression. The bandgap energies in the strained WZ InAsP core materials are extracted from the μPL measurements of individual core-shell nanowires. The coherently strained core-shell nanowires demonstrated in this work offer the potentials for use in constructing novel optoelectronic devices and for development of piezoelectric photovoltaic devices.

Crossover from Coulomb blockade to ballistic transport in InAs nanowire devices

We report on the observation of a crossover from the single electron Coulomb blockade regime to the ballistic transport in individual InAs semiconducting nanowire devices. The InAs nanowires studied here were grown by molecular-beam epitaxy (MBE), which provides a clean system to study the intrinsic electrons transport in a quasi-one-dimensional system. Quantized conductance plateaus are observed for an InAs nanowire-based device by changing the Fermi level with a global back gate at low temperature, suggesting the ballistic transport of electrons. Further lowering the temperature, we observe the Coulomb blockade phenomenon with the formation of the quantum dot between the two normal metal contacts. By increasing the electron density, the characteristic Fabry-Pérot oscillations are observed, which further provides evidence for the ballistic nature of transport in the InAs nanowire device. Our observations indicate that high-quality InAs nanowires grown by MBE behave as clean quantum wires at low temperatures, which enables us to investigate novel phenomena in the quasi-one-dimensional system.

[Correlation of health literacy and mobile phone use dependence with psychopathological symptoms in middle school students]

Objective: To explore the correlation of health literacy and mobile phone use dependence with psychopathological symptoms in middle school students. Methods: 22 628 middle school students in Shenyang, Bengbu, Xinxiang, Ulanqab, Chongqing and Yangjiang were enrolled by multistage cluster sampling method from November 2015 to January 2016. Chinese Adolescent Interactive Health Literacy Questionnaire (CAIHLQ), Self-rating Questionnaire for Adolescent Problematic Mobile Phone Use (SQAPMPU) and Multidimensional Sub-health Questionnaire of Adolescents (MSQA) were applied to acquire basic characteristics, health literacy, mobile phone use dependence and psychopathological symptoms of subjects. Subjects were classified into three groups, low level (<P(25)), medium level (P(25)-P(75)) and high level (>P(75)), according to the percentile of the questionnaire score. Multivariate logistic regression model was used to analyze the correlation of health literacy, mobile phone with psychopathological symptoms. Results: The students were (15.4±1.8) years old with 10 990 boys (48.6%). The score of health literacy of students were (104.1±18.7) points. The rate of mobile phone use dependence was 25.4% (5 752/22 628) and the rate of psychopathological symptoms was 29.1% (6 581/22 628). Compared with high health literacy level, medium and low health literacy levels were related to psychopathological symptoms, with OR (95%CI) about 2.30 (2.10-2.52) and 5.40 (4.89-5.97), respectively. Compared with mobile phone use independence, mobile phone use dependence was related to psychopathological symptoms, with OR (95%CI) about 3.60(3.37-3.85). The highest rate of psychopathological symptoms occurred in students with mobile phone use dependence and low health literacy level [68.0% (1 345/1 977)], with OR (95%CI) about 19.59 (17.07-22.48). Conclusion: Health literacy and mobile phone use dependence are related factors of psychopathological symptoms in middle school students.

Analysis of risk factors for antiepileptic drug-induced adverse psychotropic effects in Chinese outpatients with epilepsy

Antiepileptic drugs (AEDs) have adverse psychotropic effects (APEs). To explore the risk factors for AED-induced APEs, we compared Chinese outpatients with epilepsy with and without AED-induced APEs. We reviewed the medical data of outpatients with epilepsy enrolled in the Epilepsy Long-term Follow Up Registry Study (ELFURS) between January 1, 2003 and December 31, 2015. Data on demographics, comorbidities, variables related to epilepsy, AED use, and APEs were collected. APEs were determined by experienced epileptologists based on the definition of "adverse drug reaction (ADR)" proposed by the World Health Organization (WHO) in 1972, and the causality relationship between APEs and suspected medications was assessed based on the WHO-UMC scale. APEs included effects on memory, sleep, behavior, mood, psychotic symptoms, and others in this study. We divided the study population into patients with and without AED-induced APEs and then compared the differences between the two groups using univariate and multivariate methods. A total of 3074 eligible patients were included in this study (1001 patients with AED-induced APEs and 2073 patients without AED-induced APEs). Of all APEs, the effects on memory and sleep were most pronounced. The results show that the female sex (odds ratio [OR] 1.242, 95% confidence interval [CI] 1.055-1.463), psychotic disorder comorbidities (OR 1.815, 95% CI 1.159-2.841), polytherapy with AEDs (OR 1.400, 95% CI 1.061-1.847), and the duration of epilepsy (OR 1.010, 95% CI 1.000-1.020) are significant nondrug risk factors for AED-induced APEs. Recognizing risk factors for APEs may help determine optimal treatment strategies for epilepsy.

Simvastatin prevents and ameliorates depressive behaviors via neuroinflammatory regulation in mice

BACKGROUND

Statins play a beneficial role in the treatment of coronary artery disease and are widely prescribed to prevent hypercholesterolemia. Previous studies have demonstrated that statins also have anti-inflammatory and immunomodulatory properties, and these are being explored for potential benefits in depression. However, the role of statins in the treatment of depression has not been well examined.

METHODS

We investigated the effects of simvastatin on depressive behaviors and neuroinflammation in lipopolysaccharide (LPS) and chronic mild stress (CMS) induced depression model in mice. Sucrose preference test (SPT), forced swimming test (FST), novelty-suppressed feeding test (NSFT) were used to detect the depressive behaviors. The microglial activation was detected by immunohistochemistry analysis and the pro-inflammatory cytokines expressions including IL-1β, TNF-α and IL-6 were examined by Western blot analysis.

RESULTS

Our data indicated that oral administration of simvastatin at 20 mg/kg significantly prevented and ameliorated depressive behaviors reflected by better performance in the SPT, FST and NSFT. Moreover, simvastatin markedly prevented and ameliorated LPS and CMS-induced neuroinflammation, as shown by the suppressed activation of microglia in hippocampus and decreased hippocampal pro-inflammatory cytokines expressions including IL-1β, TNF-α, IL-6, which might be mediated via the inhibition of NF-κB pathway, as shown by the decreased nuclear NF-κB p65 expression.

LIMITATIONS

The interpretation of the evidence of a positive treatment effect of simvastatin on the depressive manifestations, multifaceted etiology of depression, and confirmation of this finding from animal models to humans is needed.

CONCLUSION

These results suggest that simvastatin has the potential to be employed as a therapy for depression associated with neuroinflammation.

[Interactive effects between health literacy and mobile phone dependence as well as its relation with unintentional injuries in middle school students]

Objective: To investigate the interaction between health literacy, mobile phone dependence and unintentional injuries in middle school students, and to provide guidance for prevention on unintentional injuries in adolescents. Methods: From November 2015 to January 2016, a questionnaire survey was conducted among 22 628 middle school students in Shenyang of Liaoning province, Bengbu of Anhui province, Xinxiang of Henan province, Ulanqab of Inner Mongolia Autonomous Region, Chongqing and Yangjiang of Guangdong province. Chinese Adolescent Interactive Health Literacy Questionnaire (CAIHLQ), Self-rating Questionnaire for Adolescent Problematic Mobile Phone Use (SQAPMPU), and Unintentional Injuries Assessment Scale and demographic variables were used to measure the health literacy, mobile phone dependence and unintentional injuries among the Chinese middle school students. Results: The detection rates of mobile phone dependence and unintentional injuries were 25.4% and 46.7%, respectively. The rates of unintentional injuries of middle school students with mobile phone dependence and with low, medium and high health literacy were 53.6%, 44.4% and 48.8%, 48.1%, 41.7%. Factors as mobile phone dependence, low and middle health literacy were positively related to unintentional injuries (OR=1.452, 1.196, 1.364). However, the multiplicative interaction between mobile phone dependence and health literacy on unintentional injuries was noticed significant (OR=1.217, 95%CI: 1.041-1.422). Conclusions: Our results showed that the prevalence of unintentional injuries was relatively high in middle school students. Health literacy and mobile phone dependence seemed related to unintentional injuries. Interaction between health literacy and mobile phone dependence on unintentional injuries appeared significant.

Tunable Low Loss 1D Surface Plasmons in InAs Nanowires

Due to the ability to manipulate photons at nanoscale, plasmonics has become one of the most important branches in nanophotonics. The prerequisites for the technological application of plasmons include high confining ability (λ₀ /λ_p ), low damping, and easy tunability. However, plasmons in typical plasmonic materials, i.e., noble metals, cannot satisfy these three requirements simultaneously and cause a disconnection to modern electronics. Here, the indium arsenide (InAs) nanowire is identified as a material that satisfies all the three prerequisites, providing a natural analogy with modern electronics. The dispersion relation of InAs plasmons is determined using the nanoinfrared imaging technique, and show that their associated wavelengths and damping ratio can be tuned by altering the nanowire diameter and dielectric environment. The InAs plasmons possess advantages such as high confining ability, low loss, and ease of fabrication. The observation of InAs plasmons could enable novel plasmonic circuits for future subwavelength applications.

Low-field magnetotransport in graphene cavity devices

Confinement and edge structures are known to play significant roles in the electronic and transport properties of two-dimensional materials. Here, we report on low-temperature magnetotransport measurements of lithographically patterned graphene cavity nanodevices. It is found that the evolution of the low-field magnetoconductance characteristics with varying carrier density exhibits different behaviors in graphene cavity and bulk graphene devices. In the graphene cavity devices, we observed that intravalley scattering becomes dominant as the Fermi level gets close to the Dirac point. We associate this enhanced intravalley scattering to the effect of charge inhomogeneities and edge disorder in the confined graphene nanostructures. We also observed that the dephasing rate of carriers in the cavity devices follows a parabolic temperature dependence, indicating that the direct Coulomb interaction scattering mechanism governs the dephasing at low temperatures. Our results demonstrate the importance of confinement in carrier transport in graphene nanostructure devices.

Strong spin-orbit interaction and magnetotransport in semiconductor Bi2O2Se nanoplates

Semiconductor Bi₂O₂Se nanolayers of high crystal quality have been realized via epitaxial growth. These two-dimensional (2D) materials possess excellent electron transport properties with potential application in nanoelectronics. It is also strongly expected that the 2D Bi₂O₂Se nanolayers can be an excellent material platform for developing spintronic and topological quantum devices if the presence of strong spin-orbit interaction in the 2D materials can be experimentally demonstrated. Herein, we report the experimental determination of the strength of spin-orbit interactions in Bi₂O₂Se nanoplates through magnetotransport measurements. The nanoplates are epitaxially grown by chemical vapor deposition, and the magnetotransport measurements are performed at low temperatures. The measured magnetoconductance exhibits a crossover behavior from weak antilocalization to weak localization at low magnetic fields with increasing temperature or decreasing back gate voltage. We have analyzed this transition behavior of magnetoconductance based on an interference theory, which describes quantum correction to the magnetoconductance of a 2D system in the presence of spin-orbit interaction. Dephasing length and spin relaxation length are extracted from the magnetoconductance measurements. Compared to the case of other semiconductor nanostructures, the extracted relatively short spin relaxation length of ∼150 nm indicates the existence of a strong spin-orbit interaction in Bi₂O₂Se nanolayers.

Low-Temperature and Rapid Growth of Large Single-Crystalline Graphene with Ethane

Future applications of graphene rely highly on the production of large-area high-quality graphene, especially large single-crystalline graphene, due to the reduction of defects caused by grain boundaries. However, current large single-crystalline graphene growing methodologies are suffering from low growth rate and as a result, industrial graphene production is always confronted by high energy consumption, which is primarily caused by high growth temperature and long growth time. Herein, a new growth condition achieved via ethane being the carbon feedstock to achieve low-temperature yet rapid growth of large single-crystalline graphene is reported. Ethane condition gives a growth rate about four times faster than methane, achieving about 420 µm min^-1 for the growth of sub-centimeter graphene single crystals at temperature about 1000 °C. In addition, the temperature threshold to obtain graphene using ethane can be reduced to 750 °C, lower than the general growth temperature threshold (about 1000 °C) with methane on copper foil. Meanwhile ethane always keeps higher graphene growth rate than methane under the same growth temperature. This study demonstrates that ethane is indeed a potential carbon source for efficient growth of large single-crystalline graphene, thus paves the way for graphene in high-end electronical and optoelectronical applications.

[Analysis of maternal deaths in Shanghai from 1996 to 2015]

Objective: To analyze the trend of maternal mortality ratio (MMR) and cause of death in Shanghai from 1996 to 2015. Methods: To collect the material about the maternal death and the maternal death audit from 1996 to 2015, and to analyze the MMR, the cause of death and the result of the maternal death audit of Shanghai from 1996 to 2015 retrospectively. Results: (1) The change of MMR: the MMR in Shanghai decreased from 28.84 per 100 000 live births in 1996 to 6.66 per 100 000 live births in 2015. (2) The characteristic of maternal death: the proportion of Shanghai citizens was 27.4%(121/441) and the proportion of migrant women was 72.6%(320/441). The women with advanced maternal age was 8.2% (20/243) since 1996 to 2005, and increased to 16.7% (33/198) since 2006 to 2015. Maternal deaths during pregnancy increased from 27.6%(67/243) in the first 10 years (1996-2005) to 35.4%(70/198) in the recent 10 years (2006-2015) . The intrapartum maternal deaths was 6.2%(15/243) in the first 10 years and in the recent 10 years it was zero. The proportion of postpartum deaths in the first 10 years and in the recent 10 years were 66.3% (161/243) and 64.6%(128/198) respectively. (3) The cause of maternal death: During the recent 10 years, indirect obstetric causes [63.1%(125/198)] was more than direct obstetric causes [36.9% (73/198) ] for the first time. The death causes changed significantly. Postpartum hemorrhage remained the leading cause of maternal deaths, but the specific mortality rate (SMR) of postpartum hemorrhage decreased significantly from 7.42 per 100 000 live births in the first 10 years to 1.51 per 100 000 live births in the recent 10 years. The maternal deaths because of heart disease and cerebrovascular disease rose to the second and the forth reasons. (4) Maternal death audit: the avoidable maternal death ratio decreased from 3.66 per 100 000 live births in the first 10 years to 1.86 per 100 000 live births in the recent 10 years. Conclusions: During the past 20 years, the MMR of Shanghai decreased significantly and was close to the level of developed countries. In recent years, the causes of maternal death become more complicated. With the implementation of the second child policy, women with high risk factors increase, so government investment, policy support should be strengthened to optimize the management.

Coherent Transport in a Linear Triple Quantum Dot Made from a Pure-Phase InAs Nanowire

A highly tunable linear triple quantum dot (TQD) device is realized in a single-crystalline pure-phase InAs nanowire using a local finger gate technique. The electrical measurements show that the charge stability diagram of the TQD can be represented by three kinds of current lines of different slopes and a simulation performed based on a capacitance matrix model confirms the experiment. We show that each current line observable in the charge stability diagram is associated with a case where a QD is on resonance with the Fermi level of the source and drain reservoirs. At a triple point where two current lines of different slopes move together but show anticrossing, two QDs are on resonance with the Fermi level of the reservoirs. We demonstrate that an energetically degenerated quadruple point at which all three QDs are on resonance with the Fermi level of the reservoirs can be built by moving two separated triple points together via sophistically tuning of energy levels in the three QDs. We also demonstrate the achievement of direct coherent electron transfer between the two remote QDs in the TQD, realizing a long-distance coherent quantum bus operation. Such a long-distance coherent coupling could be used to investigate coherent spin teleportation and superexchange effects and to construct a spin qubit with an improved long coherent time and with spin state detection solely by sensing the charge states.

High electron mobility and quantum oscillations in non-encapsulated ultrathin semiconducting Bi2O2Se

High-mobility semiconducting ultrathin films form the basis of modern electronics, and may lead to the scalable fabrication of highly performing devices. Because the ultrathin limit cannot be reached for traditional semiconductors, identifying new two-dimensional materials with both high carrier mobility and a large electronic bandgap is a pivotal goal of fundamental research. However, air-stable ultrathin semiconducting materials with superior performances remain elusive at present. Here, we report ultrathin films of non-encapsulated layered Bi₂O₂Se, grown by chemical vapour deposition, which demonstrate excellent air stability and high-mobility semiconducting behaviour. We observe bandgap values of ∼0.8 eV, which are strongly dependent on the film thickness due to quantum-confinement effects. An ultrahigh Hall mobility value of >20,000 cm² V^-1 s^-1 is measured in as-grown Bi₂O₂Se nanoflakes at low temperatures. This value is comparable to what is observed in graphene grown by chemical vapour deposition and at the LaAlO₃-SrTiO₃ interface, making the detection of Shubnikov-de Haas quantum oscillations possible. Top-gated field-effect transistors based on Bi₂O₂Se crystals down to the bilayer limit exhibit high Hall mobility values (up to 450 cm² V^-1 s^-1), large current on/off ratios (>10⁶) and near-ideal subthreshold swing values (∼65 mV dec^-1) at room temperature. Our results make Bi₂O₂Se a promising candidate for future high-speed and low-power electronic applications.

Electron-Hole Symmetry Breaking in Charge Transport in Nitrogen-Doped Graphene

Graphitic nitrogen-doped graphene is an excellent platform to study scattering processes of massless Dirac Fermions by charged impurities, in which high mobility can be preserved due to the absence of lattice defects through direct substitution of carbon atoms in the graphene lattice by nitrogen atoms. In this work, we report on electrical and magnetotransport measurements of high-quality graphitic nitrogen-doped graphene. We show that the substitutional nitrogen dopants in graphene introduce atomically sharp scatters for electrons but long-range Coulomb scatters for holes and, thus, graphitic nitrogen-doped graphene exhibits clear electron-hole asymmetry in transport properties. Dominant scattering processes of charge carriers in graphitic nitrogen-doped graphene are analyzed. It is shown that the electron-hole asymmetry originates from a distinct difference in intervalley scattering of electrons and holes. We have also carried out the magnetotransport measurements of graphitic nitrogen-doped graphene at different temperatures and the temperature dependences of intervalley scattering, intravalley scattering, and phase coherent scattering rates are extracted and discussed. Our results provide an evidence for the electron-hole asymmetry in the intervalley scattering induced by substitutional nitrogen dopants in graphene and shine a light on versatile and potential applications of graphitic nitrogen-doped graphene in electronic and valleytronic devices.

Epitaxial Growth of Ternary Topological Insulator Bi2 Te2 Se 2D Crystals on Mica

Nanostructures of ternary topological insulator (TI) Bi₂ Te₂ Se are, in principle, advantageous to the manifestation of topologically nontrivial surface states, due to significantly enhanced surface-to-volume ratio compared with its bulk crystals counterparts. Herein, the synthesis of 2D Bi₂ Te₂ Se crystals on mica via the van der Waals epitaxy method is explored and systematically the growth behaviors during the synthesis process are investigated. Accordingly, 2D Bi₂ Te₂ Se crystals with domain size up to 50 µm large and thickness down to 2 nm are obtained. A pronounced weak antilocalization effect is clearly observed in the 2D Bi₂ Te₂ Se crystals at 2 K. The method for epitaxial growth of 2D ternary Bi₂ Te₂ Se crystals may inspire materials engineering toward enhanced manifestation of the subtle surface states of TIs and thereby facilitate their potential applications in next-generation spintronics.

Synthesis of Bi₂Te₃ Nanotubes Using Te Nanotubes as a Template

Bi₂Te₃ nanotubes are synthesized by a facile two-step hydrothermal method. Te nanotubes are prepared firstly and then used as a template to produce Bi₂Te₃ nanotubes. The structure and morphology of the synthesized nanotubes are characterized by X-ray diffraction, field emission scanning electron microscope, and transmission electron microscope. The synthesized Bi₂Te₃ nanotubes are several microns in length and about 400 nm in diameter. The growth process is investigated in detail under different experimental conditions. The formation mechanism of Bi₂Te₃ nanotubes from the Te nanotube template is proposed and discussed. Electrical property of single Bi₂Te₃ nanotube is investigated. The synthesis of smooth Bi₂Te₃ nanotubes opens up the opportunities of investigating novel physical phenomena of topological insulators with two independent surfaces.

Growth of High Material Quality Group III-Antimonide Semiconductor Nanowires by a Naturally Cooling Process

We report on a simple but powerful approach to grow high material quality InSb and GaSb nanowires in a commonly used tube furnace setup. The approach employs a process of stable heating at a high temperature and then cooling down naturally to room temperature with the nanowire growth occurred effectively during the naturally cooling step. As-grown nanowires are analyzed using a scanning electron microscope and a transmission electron microscope equipped with an energy-dispersive X-ray spectroscopy setup. It is shown that the grown nanowires are several micrometers in lengths and are zincblende InSb and GaSb crystals. The FET devices are also fabricated with the grown nanowires and investigated. It is shown that the grown nanowires show good, desired electrical properties and should have potential applications in the future nanoelectronics and infrared optoelectronics.

InAs/GaSb core-shell nanowires grown on Si substrates by metal-organic chemical vapor deposition

We report the growth of InAs/GaSb core-shell heterostructure nanowires with smooth sidewalls on Si substrates using metal-organic chemical vapor deposition with no assistance from foreign catalysts. Sb adatoms were observed to strongly influence the morphology of the GaSb shell. In particular, Ga droplets form on the nanowire tips when a relatively low TMSb flow rate is used, whereas the droplets are missing and the radial growth of the GaSb is enhanced due to a reduction in the diffusion length of the Ga adatoms when the TMSb flow rate is increased. Moreover, transmission electron microscopy measurements revealed that the GaSb shell coherently grew on the InAs core. The results obtained here show that the InAs/GaSb core-shell nanowires grown using the Si platform have strong potential in the fabrication of future nanometer-scale devices and in the study of fundamental quantum physics.

Schottky barrier and contact resistance of InSb nanowire field-effect transistors

Understanding of the electrical contact properties of semiconductor nanowire (NW) field-effect transistors (FETs) plays a crucial role in the use of semiconducting NWs as building blocks for future nanoelectronic devices and in the study of fundamental physics problems. Here, we report on a study of the contact properties of Ti/Au, a widely used contact metal combination, when contacting individual InSb NWs via both two-probe and four-probe transport measurements. We show that a Schottky barrier of height [Formula: see text] is present at the metal-InSb NW interfaces and its effective height is gate-tunable. The contact resistance ([Formula: see text]) in the InSb NWFETs is also analyzed by magnetotransport measurements at low temperatures. It is found that [Formula: see text] in the on-state exhibits a pronounced magnetic field-dependent feature, namely it is increased strongly with increasing magnetic field after an onset field [Formula: see text]. A qualitative picture that takes into account magnetic depopulation of subbands in the NWs is provided to explain the observation. Our results provide solid experimental evidence for the presence of a Schottky barrier at Ti/Au-InSb NW interfaces and can be used as a basis for design and fabrication of novel InSb NW-based nanoelectronic devices and quantum devices.

Covalently bonded single-molecule junctions with stable and reversible photoswitched conductivity

Through molecular engineering, single diarylethenes were covalently sandwiched between graphene electrodes to form stable molecular conduction junctions. Our experimental and theoretical studies of these junctions consistently show and interpret reversible conductance photoswitching at room temperature and stochastic switching between different conductive states at low temperature at a single-molecule level. We demonstrate a fully reversible, two-mode, single-molecule electrical switch with unprecedented levels of accuracy (on/off ratio of ~100), stability (over a year), and reproducibility (46 devices with more than 100 cycles for photoswitching and ~10(5) to 10(6) cycles for stochastic switching).