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OBJECTIVE: The aim of this study was to investigate and evaluate the risk of dyspepsia and anorexia in patients with type 2 diabetes mellitus (T2DM) induced by glucagon-like peptide 1 receptor agonist (GLP-1 RA) hypoglycemic drugs. MATERIALS AND METHODS: We searched papers in PubMed, Web of Science, Cochrane Library, Google Scholar, CNKI, Wanfang, Embase and VIP databases, and the retrieval time limit was set from the establishment of the database to May 2023. Randomized Controlled Trials (RCTs) were collected in which the subjects were T2DM patients, the intervention was GLP-1RA compared with placebo or traditional hypoglycemic drugs, and the outcome indicators included dyspepsia and anorexia. A meta-analysis and a network meta-analysis were performed. RESULTS: The results of the traditional meta-analysis showed that the risk of dyspepsia and anorexia of total GLP-1 RA was 3.01 and 2.56 times that of placebo, respectively. All types of GLP-1RA were compared with placebo and the results also showed a trend towards increased risk of digestive system adverse events (DSAEs). Among all interventions included, liraglutide was the one with the highest risk of dyspepsia in patients with T2DM, and dulaglutide was the one with the highest risk of anorexia. CONCLUSIONS: The results of the two meta-analyses are consistent, and both clearly show that GLP-1RA can increase the risk of dyspepsia and anorexia in T2DM patients. [ABSTRACT FROM AUTHOR]

The direct conversion of CO2 to aromatics is an effective strategy for simultaneously achieving carbon neutrality and its resource utilization. However, it is a great challenge to efficient CO2 conversion to high value-added aromatics due to the chemical inertness and characteristics of multi-path conversion of CO2. In this work, a series of nanosized ZSM-5 zeolites [NZ5(x)] with different acid amount and strength were synthesized by a seed-induced template-free method via changing the initial gel composition. The Cr2O3 nanoparticle was prepared by simple precipitation method. The performance of the Cr2O3/NZ5(x) bifunctional catalysts composed of Cr2O3 and nano-ZSM-5 zeolites with different acidity, and mixed Cr2O3 with NZ5 (50) by different ways in the CO2 hydrogenation reaction was investigated. The Cr2O3/NZ5(50) catalyst with suitable acidity and closest metal-acid site distance exhibit the highest aromatics selectivity of 87.2% among all hydrocarbon products at CO2 single-pass conversion of 13.6%, which is due to the synergistic effect between the acid sites of the nanosized ZSM-5 zeolite and metal sites provide by Cr2O3 with abundant oxygen vacancies. [ABSTRACT FROM AUTHOR]

Improving the contact characteristics of Ti/Al/Ni/Au on plasma etched n-AlGaN has been attempted by an active pretreatment, which can provide Si and N atoms to occupy the possible metal and N vacancies. It is found that the contacts on both the as-grown and plasma-etched + pretreatment n-Al0.5Ga0.5N present truly Ohmic in nature, whereas the contacts on plasma-etched samples without pretreatment still remain rectifying. Surface atomic concentration analysis indicates that the plasma etching induced N or metal vacancies mostly act as acceptor-like states, leading to a severe compensation. Fortunately, these states can be effectively removed by the presently proposed pretreatment, and thus the Fermi level is raised up toward the conduction band edge, ensuring the formation of Ohmic contacts. [ABSTRACT FROM AUTHOR]

Accurate streamflow estimation remains a great challenge although diverse modeling techniques have been developed during recent decades. In contrast to the process based models, the empirical data driven methods are easy to operate, require low computing capacity and yield fairly accurate outcomes, among which the state space (STATE) approach takes use of the temporal structures inherent in streamflow series and serves as a feasible solution for streamflow estimation. Yet this method has rarely been applied, neither its comparison with other methods. The objective was to compare the performance of an autoregressive STATE approach to the traditional multiple linear regression and artificial neural network in simulating annual streamflow series of 15 catchments located in the Loess Plateau of China. Annual data of streamflow (Q), precipitation (P) and potential evapotranspiration (PET) during 1961 ~ 2013 were collected. The results show that STATE was generally the most accurate method for Q estimation, explaining almost 90% of the total variance averaged over all the 15 catchments. The estimation of streamflow relied on its own of the previous year for most catchments. Besides, the impacts of P and PET on the temporal distribution of streamflow were almost equal. Missing data were estimated using the STATE method, which allowed inter annual trend analysis of the streamflow. Significant downward trends were manifested at all the 15 catchments during the study period and the corresponding slopes ranged from 0.24 to 1.71 mm/y. These findings hold important implications for hydrological modelling and management in China's Loess Plateau and other arid and semi-arid regions [ABSTRACT FROM AUTHOR]

Carrier velocity modulation by asymmetrical concave quantum barriers to improve the performance of AlGaN-based deep-ultraviolet light emitting diodes has been investigated. The concave structure is realized by inserting a low Al composition AlGaN layer in the barrier, and thus forming a concave region on energy band. The measured device performance shows a significant improvement under 0–250 mA operation current, with the maximum external quantum efficiency and light output power of 1.02% and 8.0 mW, which are more than double (2.32 and 2.35 times) of that for the conventional one, respectively. Simulation confirms that the concave quantum barriers make it possible for electrons to be scattered, which reduce the electron energy before being injected into quantum wells, and thus the capability of quantum wells to capture electrons is enhanced. Meanwhile, the vertical transport of holes within the active region is also enhanced because the asymmetrical setting of the concave layer in the quantum barriers helps holes accelerate under the polarization field, and then get more energy to overcome the barrier. [ABSTRACT FROM AUTHOR]

In this work, we have designed excellent performance GaN-based Schottky barrier diode (SBD) with a sandwich structure by inserting a graphene (Gr) interlayer. The electrical properties of Pt/Gr/GaN and Pt/GaN SBDs have been systematically investigated by the temperature-dependent current—voltage (I–V) and capacitance–voltage measurements in order to explore the effects of Gr on main diode parameters. At room temperature, the Pt/Gr/GaN SBD exhibited lower turn-on voltage (Von), ideality factor (n), differential specific on-resistance (Ron), and higher Schottky barrier height (SBH), signifying enhanced device attributes. Furthermore, the ideality factor and SBH for the Pt/Gr/GaN SBD were found to be insensitive to temperature from the temperature-dependent I–V analysis. The results revealed a highly homogeneous Schottky barrier interface in the case of Pt/Gr/GaN SBD. This facile strategy opened a pathway to improve the performance of the nitride Schottky rectifiers. [ABSTRACT FROM AUTHOR]

Developing efficient active region structures with low sensitivity to threading dislocation density (TDD) is of great technical significance for AlGaN-based deep ultraviolet (DUV) light-emitting devices. Here, we propose an active region strategy by introducing bunching effect to form self-assembled sidewall quantum wells (SQWs) with much stronger carrier confinement, resulting in a significant enhancement of internal quantum efficiency (from 46% to 59%) compared to the commonly adopted multiple quantum wells (MQWs) due to the lower sensitivity to TDD. As a demo, an AlGaN-based DUV light-emitting diode (LED) with the proposed active region involving both SQWs and MQWs presents dual-band emission and a consequent 68% enhancement in light output power compared to the DUV-LED with only MQWs as the active region, suggesting that the proposed architecture is fully suitable for the development of high performance DUV light-emitting devices even based on poor or medium quality materials. [ABSTRACT FROM AUTHOR]

Evolution of crystalline quality of AlN via high-temperature (HT) annealing induced by different sapphire pretreatments is investigated. It is found that after HT annealing at 1700 °C for one hour, an AlN film grown on a nitridation treated sapphire substrate presents a much lower threading dislocation density (TDD) than that grown on an alumination treated one, indicating that the combination of nitridation and HT annealing is a more effective approach to achieve high quality AlN. It is verified that the much greater grain density of the nucleation layer induced by nitridation can produce more columns with much smaller sizes so that they can more easily rotate during the HT annealing to reduce the TDD more effectively. A deep ultraviolet light-emitting diode (285 nm) with an output power over 10 mW has been demonstrated on a HT annealed AlN template with sapphire substrate nitridation pretreatment, showing great potential for applications. [ABSTRACT FROM AUTHOR]

AlGaN-based deep-ultraviolet light emitting diodes adopting an embedded delta-AlGaN thin layer with an Al composition higher than that in conventional barriers have been investigated. The experimental result shows that when the current is below 250 mA, the maximum of the external quantum efficiency and light output power for the proposed structure reach severally 1.38% and 10.1 mW, which are enhanced significantly by 160% and 197%, respectively, compared to the conventional ones, showing a tremendous improvement. We attribute that to the inserted delta-thin layer's modulation effect on the energy band, namely, accelerating holes to cross the high barrier with very large kinetic energy, thus increasing the hole injection into the active regions. Meanwhile, the electron concentration within the active regions is enhanced as well because of the accompanying additional effect of the delta-AlGaN thin layer being an electron barrier to block electrons escaping from the active region. [ABSTRACT FROM AUTHOR]

Growth behaviors of AlN on hexagonal configuration hole-type and truncated-cone-pillar-type nano-patterned sapphire substrates (NPSSs) have been investigated. It is found that threading dislocation density (TDD) of AlN grown on the hole-type NPSS reaches 4.87 × 108 cm−2, which is over one order of magnitude lower than the value 6.63 × 109 cm−2 on the pillar-type one with the same period and mesa width. It is verified that the TDD of AlN grown on NPSSs is greatly dominated by the area ratio of the coalescence zones and thus the NPSS pattern with a small coalescence area (SCA) ratio is the preferred choice for high-quality AlN epitaxy. Benefiting from the low-TDD AlN grown on the hole-type NPSS with an SCA, the internal quantum efficiency of the 281 nm AlGaN-based multiple quantum wells has reached 73.9% at 300 K. [ABSTRACT FROM AUTHOR]

High-temperature (HT) annealing effects on the evolution of strain in AlN films grown on sapphire have been investigated. It is found that there is a significant transition behavior from tensile to compressive strain in AlN before and after HT annealing at an optimal temperature of 1700 °C. Based on a microstructural analysis, it is clarified that the HT annealing will result in the (1) disappearance of grains that account for the tensile stress before HT annealing, (2) generation of a new interface that has little influence on the lattice constant upper/below this interface, and (3) regular 8/9 arrangement of misfit dislocation at the AlN/sapphire interface that relieves almost all stress associated with lattice mismatch. It is thus deduced that the remnant compressive strain in AlN after HT annealing mainly comes from the cooling down process due to thermal mismatch between sapphire and AlN. This understanding of the annealing effect is certainly of great significance in AlN materials science and technology. [ABSTRACT FROM AUTHOR]

The crystal quality evolution of AlN films via high-temperature (HT) annealing under nitrogen is investigated. It is found that the best crystal quality can be realized using an optimized combination of the annealing temperature at 1700 °C and an AlN thickness of 540 nm, respectively. Thus the X-ray diffraction ̉-scan full width at half maximum (FWHM) values of 59 and 284 arcsec for (0002) and (101̅2) diffractions were achieved, respectively. It is verified that the significant reduction in the threading dislocation density (TDD) via HT annealing starts from the interface zone between AlN and sapphire anterior to the zone far from the interface, which is caused by less energy being required to decrease the larger twist angle among the columns in the interface zone. Benefiting from the low-TDD annealed AlN template, the internal quantum efficiency of the 282-nm AlGaN-based multiple quantum wells reached 57% at 300 K. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To elucidate the role of microRNA-31 (miR-31) in osteosarcoma and the molecular mechanism of miR-31 in the proliferation, migration, and invasion of osteosarcoma. PATIENTS AND METHODS: Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was used to examine the expression of microRNA- 31 in human osteosarcoma tissues. Pearson's chi-squared test was used to analyze the correlation between microRNA-31 and clinicopathological features. Proliferation, migration, invasion, and PI3K3C2A protein in treated osteosarcoma cells were detected by Cell Counting Kit-8 (CCK-8) assay, transwell assay without Matrigel, transwell assay with Matrigel, and Western blot analysis, respectively. RESULTS: qRT-PCR showed that miR-31 was down-regulated in osteosarcoma tissues compared with paired para-tumor bone tissues. The lower level of miR-31 was closely associated with high-grade osteosarcoma, metastasis, and poor overall survival. CCK-8 and transwell assay showed that miR-31 inhibited osteosarcoma cells proliferation, migration, and invasion. According to luciferase assay, miR-31 inhibits osteosarcoma cell proliferation, migration, and invasion through inhibiting PIK3C2A. Reversely, overexpression of PIK3C2A inhibited partial effect of miR-31 on proliferation, migration, and invasion in vitro. CONCLUSIONS: MiR-31 inhibits osteosarcoma cell proliferation, migration, and invasion by targeting PICK3C2A. MiR-31 can thus be used as a therapeutic target in osteosarcoma treatment. [ABSTRACT FROM AUTHOR]

Focuses on a study that reported the conduction enhancement characteristics and the conduction mechanism in nitroxide. Sample preparation and measurements; Results; Discussion; Conclusions.

Abstract: Phlebotomine sandflies (Diptera: Phlebotomidae) are vectors of the zoonotic disease leishmaniasis. To better understand the distribution of phlebotomine sandflies in order to facilitate control of leishmaniasis transmission, the present study explored the impacts of climate and landscape on local abundances of Phlebotomus chinensis in northwestern mainland China. Identification records were used to create a geodatabase for the locations at which P. chinensis had been collected in the region, and a regional‐scale map was developed to show the distribution of P. chinensis. Location data and data on environmental factors during the years in which the samples were collected were incorporated, and a presence‐only modelling method was used to evaluate the species' habitat preferences and to predict its potential distribution in northwestern mainland China. Jackknife analysis revealed that several meteorological variables, including maximum temperature in the warmest quarter, precipitation in the driest month, daily average temperature and daily precipitation, significantly affected the presence of this species. Moreover, the presence of P. chinensis was significantly associated with grassland and shrubland. Probability distributions using maximum entropy were used to map the distribution ranges of P. chinensis based on suitable habitats in northwestern mainland China. The models generated can be used to develop detailed strategies for the prevention and control of leishmaniasis. [ABSTRACT FROM AUTHOR]

Although the 137Cs technique has been widely used to estimate soil redistribution in past decades, most 137Cs-conversion models have not been rigorously validated. The objective of this study was to explicitly evaluate the sediment deposition components of three widely used 137Cs models using 34 yr of soil loss data from a plot (200 × 80 m). The average slope of the plot is approximately 4% in the upper section and 1% in the lower section. The primary soil (fine, mixed, thermic, Udertic or Pachic Paleustoll) is silt loam with 23% sand and 56% silt. Winter wheat (Triticum aestivum L.) was raised primarily under conventional tillage. Sediment load was measured with a pump sampler at the outlet. Bulk soil cores were taken in a 10-m grid to estimate 137Cs inventory. The 137Cs depth profiles were measured at eight locations to determine net deposition depth. The proportional model (PM) and two mass balance models (mass balance model 1 [MBM1] and mass balance model 2 [MBM2]) were evaluated. The measured average deposition depth in the depositional area of the lower section was 5.83 cm, and the predicted deposition depths in the area were 4.12, 2.02, and 1.64 cm for PM, MBM1, and MBM2. The results indicated that the simple PM appeared to predict deposition depths better than the two sophisticated mass balance models under the study conditions. However, the true capability of the two mass balance models needs to be further evaluated under more complex conditions that include the critical period of 137Cs peak fallout in the 1950s and 1960s. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Deep vein thrombosis (DVT) is one of the most common complications for patients undergoing spinal surgery. This study aims to investigate preventive effects of low-molecular-weight heparin (LMWH) on the formation of DVT. PATIENTS AND METHODS: This study involved 37 patients who underwent spinal surgery between April 2016 and April 2017. Patients were divided into LMWH group and Control group. Clinical parameters, including operation time, intra-operative blood loss, incision length, post-operative visual analogue scale (VAS), exercise- time leaving bed and post-operative extubation time, were collected. Blood routine analysis, including platelet count (PLT), red blood cell count (RBC), white blood cell count (WBC) and hemoglobin (HGB) were also conducted. Coagulation parameters, including prothrombin time-international normalized ratio (PT-INR), fibrinogen (FIB), activated partial thromboplastin time (APTT), thrombin time (TT), prothrombin time 1 (PT-1) and D-dimer (DD), were evaluated. The drainage fluid was collected. RESULTS: LMWH treatment significantly decreased operative time, blood loss and incision length compared to Control group at 1st, 3rd and 7th day post-operation (all p<0.05). LMWH treatment significantly increased WBC levels compared to Control group at 1st, 3rd and 7th day post-operation (p<0.05). LMWH treatment significantly decreased DD levels in the post-operative patients compared to Control group at 1st, 3rd and 7th day post-operation (p<0.05). However, LMWH treatment doesn't affect drainage amounts of patients. DD levels were positively correlated with WBC counts for the LMWH treated patients. CONCLUSIONS: Low molecular weight heparin effectively prevents the formation of DVT by reducing DD values in patients undergoing spinal surgery. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the role of miR-145 silencing in the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), B-cell lymphoma-2 (Bcl-2), BCL2-Associated X(bax) and caspase-3 in avascular necrosis of femoral head (ANFH). MATERIALS AND METHODS: A total of 12 healthy wild-types (the control group) and 12 miR-145 knock-out (miR-145-/-) (the experimental group) adult New Zealand white rabbits were selected to construct ANFH model with steroid. Four weeks later, immunohistochemistry, qRTPCR and Western blot were performed to measure the VEGF, bFGF, Bcl-2, bax, caspase-3, β-catenin as well as c-Myc expression. Terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) staining analysis was used to detect the apoptosis of bone cells in each group. RESULTS: Compared with the control group, the expression of VEGF, bFGF, Bcl-2, β-catenin and c-Myc in the miR-145-/- group raised (p<0.05). Moreover, the expression level of bax and caspase-3 significantly decreased in the miR- 145-/- group (p<0.05). TUNEL staining showed decreased apoptosis in the miR-145-/- group. CONCLUSIONS: MiR-145 silencing promotes bone repair of ANFH via upregulating VEGF, bFGF and inhibiting the bone cells apoptosis through Wnt/β-catenin pathway. [ABSTRACT FROM AUTHOR]

A double layer composite coating on Q235 steel substrate was prepared using a new developed in situ technology consisting of a self-propagation high-temperature synthesis (SHS) reaction, laser cladding and metal dusting techniques. The samples were subjected to various microstructural examinations and the microhardness was also measured. A double layer composite coating consisted of TiO2-TiC ceramic outer layer and a TiC-carbon nano-tubes (CNTs) cermet inner layer. An excellent bonding was observed among the outer layer, the inner layer and the steel substrate. The TiO2 distributed uniformly in the microstructure and a small number of porosities were seen in the outer layer. The cermet inner layer consisted of γ-(Fe, Ni) as a metallic matrix binder and TiC-CNTs as a reinforced phase in the microstructure. The hardness of the coating was significantly higher than that of the substrate. [ABSTRACT FROM AUTHOR]

Presents a study which investigated the temperature dependance of electronic conduction in thin nitrided oxides. Sample fabrication; Discussion of the conduction currents in the nitrided oxides; Conclusions.

Background: Tea is the world’s most popular non-alcoholic beverage. China and India are known to be the largest tea producing countries and recognized as the centers for the domestication of the tea plant (Camellia sinensis (L.) O. Kuntze). However, molecular studies on the origin, domestication and relationships of the main teas, China type, Assam type and Cambod type are lacking. Methodology/Principal Findings: Twenty-three nuclear microsatellite markers were used to investigate the genetic diversity, relatedness, and domestication history of cultivated tea in both China and India. Based on a total of 392 samples, high levels of genetic diversity were observed for all tea types in both countries. The cultivars clustered into three distinct genetic groups (i.e. China tea, Chinese Assam tea and Indian Assam tea) based on STRUCTURE, PCoA and UPGMA analyses with significant pairwise genetic differentiation, corresponding well with their geographical distribution. A high proportion (30%) of the studied tea samples were shown to possess genetic admixtures of different tea types suggesting a hybrid origin for these samples, including the Cambod type. Conclusions: We demonstrate that Chinese Assam tea is a distinct genetic lineage from Indian Assam tea, and that China tea sampled from India was likely introduced from China directly. Our results further indicate that China type tea, Chinese Assam type tea and Indian Assam type tea are likely the result of three independent domestication events from three separate regions across China and India. Our findings have important implications for the conservation of genetic stocks, as well as future breeding programs. [ABSTRACT FROM AUTHOR]

Seed injection is an important technology in single longitude mode laser for Doppler wind lidar (DWL). Different methods of seed injection lead to difference of anti-jamming of the system. For mobile and airborne wind lidar, vibration influences the frequency stability of laser, which results in frequency jitter and larger errors in wind measurements. The frequency stability of locked lasers with the technology of build-up time minimization and ramp-fire technology are investigated respectively to compare the dependence of frequency stability on vibration. Results show that the frequency-locked 532 nm pulsed laser with ramp-fire technology has frequency stability of less than 5.00 MHz under vibration condition, while the frequency stability of the laser with build-up time minimization technology reaches up to 9.00 MHz. This suggests that the laser with ramp-fire technology is more suitable than laser with built-up time minimization technology for DWL used in the vibration environment. [ABSTRACT FROM AUTHOR]

We present a curve fitting approach for calculating both transmittance and optical rotation angles via the measurement system based on optical null methods. The system contains a digital signal processor (DSP) controlled step-motor rotating stage structure and a modulated laser diode (LD). Ink and sugar solutions of different concentrations are tested. Results for dual parameter measurement have been discussed. The feasibility, accuracy, along with the wide measuring range of this fitting approach is verified. [ABSTRACT FROM AUTHOR]

Inner suspension platform of a spherical robot undergoes dynamic oscillation process when the robot is rolling ahead, which significantly reduces stability and precision of the motion. To suppress these vibrations, this study considers an adaptive sliding mode control method for a spherical robot based on application of magnetorheological (MR) fluid actuator. After analyzing the mechanical structure of the spherical robot, a dynamic model describing its rolling motion is derived. Considering the uncertainty of the disturbances introduced by modeling error and outside perturbation, an adaptive scheme is proposed to estimate the dynamic disturbances. Sliding mode technology is applied to construct system controller characterized by robustness and parameter insensibility. Simulations are performed in order to verify the effectiveness of the proposed control methods. [ABSTRACT FROM AUTHOR]