During winters, the high-speed train travels in the northern of China is struck by to the snow, ice and coldness, massive snow accumulating on the bogies. To understand the cause of snow packing on ...the high-speed train’s bogies clearly, the 3-D unsteady Reynolds-averaged Navier-Stokes equations with a RNG double-equations turbulence model and a DPM discrete phase model were used to investigate the flow field carried snow particles in a single high-speed train bogie region and monitor the movement of snow particles. And, the numerical simulation was verified by the wind tunnel test. The results show that when air flows into the region, the airflow will rise and impact on the wheels, brakes, electromotors and other parts of bogie regions. The snow particles will follow the air, while the air direction changes sharply the particles will keep the movement due to the inertia. Afterwards, the snow packs on the bogie. In front of the bogies the streamlines of the air and the particle path lines are basically the same. However, due to the inertia of mass particles, the following characteristics of the snow particles with the air are not obvious in the bogie leeward side. Different structures of the end plates will affect the snow accumulation in the bogie regions.
Retinopathy of prematurity (ROP) is the leading cause of preventable childhood blindness worldwide. Although interventions such as anti-VEGF and laser have high success rates in treating severe ROP, ...current treatment and preventative strategies still have their limitations. Thus, we aim to identify drugs and chemicals for ROP with comprehensive safety profiles and tolerability using a computational bioinformatics approach.
We generated a list of genes associated with ROP to date by querying PubMed Gene which draws from animal models, human studies, and genomic studies in the NCBI database. Gene enrichment analysis was performed on the ROP gene list with the ToppGene program which draws from multiple drug-gene interaction databases to predict compounds with significant associations to the ROP gene list. Compounds with significant toxicities or without known clinical indications were filtered out from the final drug list.
The NCBI query identified 47 ROP genes with pharmacologic annotations present in ToppGene. Enrichment analysis revealed multiple drugs and chemical compounds related to the ROP gene list. The top ten most significant compounds associated with ROP include ascorbic acid, simvastatin, acetylcysteine, niacin, castor oil, penicillamine, curcumin, losartan, capsaicin, and metformin. Antioxidants, NSAIDs, antihypertensives, and anti-diabetics are the most common top drug classes derived from this analysis, and many of these compounds have potential to be readily repurposed for ROP as new prevention and treatment strategies.
This bioinformatics analysis creates an unbiased approach for drug discovery by identifying compounds associated to the known genes and pathways of ROP. While predictions from bioinformatic studies require preclinical/clinical studies to validate their results, this technique could certainly guide future investigations for pathologies like ROP.
There are few systematic evaluations regarding the sixth and seventh editions of the UICC/AJCC TNM Staging System (TNM6th, TNM7th) and Chinese 2008 Staging System (TNMc2008) for nasopharyngeal ...carcinoma (NPC).
We classified 2333 patients into intensity-modulated radiotherapy (IMRT) cohort (n=941) and conventional radiotherapy (CRT) cohort (n=1392). Tumour staging defined by TNM6th, TNM7th and TNMc2008 was compared based on Akaike information criterion (AIC) and Harrell's concordance index (c-index).
For T-classification, TNM6th (AIC=2585.367; c-index=0.6390385) had superior prognostic value to TNM7th (AIC=2593.242; c-index=0.6226889) and TNMc2008 (AIC=2593.998; c-index=0.6237146) in the IMRT cohort, whereas TNMc2008 was superior (AIC=5999.054; c-index=0.623547) in the CRT cohort. For N-classification, TNMc2008 had the highest prognostic value in both cohorts (AIC=2577.726, c-index=0.6297874; AIC=5956.339, c-index=0.6533576). Similar results were obtained when patients were stratified by chemotherapy types, age and gender. Using staging models in the IMRT cohort, we failed to identify better stage migrations than TNM6th T-classification and TNMc2008 N-classification. We therefore proposed to combine these categories; resultantly, stage groups of the proposed staging system showed superior prognostic value over TNM6th, TNM7th and TNMc2008.
TNM6th T-classification and TNMc2008 N-classification have superior prognostic value in the IMRT era. By combining them with slight modifications, TNM criteria can be unified and its prognostic value be improved.
Linear friction welds of a Ti2AlNb-based alloy were subjected to post-weld heat treatment (PWHT) at 815°C×1h (PWHT1) and at 1000°C×1h+815°C×2h (PWHT2) followed by air cooling. The microstructure and ...mechanical properties of the joints under as weld and PWHT conditions were investigated. The results indicate that in the as weld joint, the weld zone mainly consists of B2 phase while the quantity of α2 and O phase is relatively small, and most O phase gradually turns into B2 phase when the amount of α2 phase reduces as well in thermo-mechanically affected zone (TMAZ). After PWHT1, O precipitates within recrystallized B2 grains can be found in weld zone and the decomposition of α2 phase caused by niobium diffusion is found in TMAZ. PWHT1 have significantly enhanced the mechanical properties due to the O phase precipitation hardening and refined grain strengthening. And the coarsening of the microstructure in weld zone under PWHT2 is evident, which consequently reduces the elongation.
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•Post-weld treatments significantly affect the microstructure of Ti2AlNb joint.•Acicular O phases have precipitated within B2 grains after post-weld heat treatments.•The high temperature and holding time have interaction on grain growth in weld zone.•The refined B2 grains and O precipitates enhanced the mechanical properties of the joint.
The aim is to showcase the effectiveness and safety of bosentan or ambrisentan in individuals diagnosed with idiopathic pulmonary fibrosis (IPF) and offer fresh evidence for the management of this ...condition.
For this research, we conducted a meta-analysis of randomized controlled trials by searching various databases, including the Cochrane Library, Excerpta Medica Database, PubMed, and Web of Science. The retrieval was conducted until November 2021. We analyzed the variances in 6-minute walk distance (6MWD), death, diffusion capacity for carbon monoxide (DLCO), forced vital capacity (FVC), hospitalization, IPF worsening, mean pulmonary arterial pressure, serious adverse events (SAEs), Short Form-36 improved, and St. George's Respiratory Questionnaire between the treatment and control groups.
A sum of six studies involving 1,928 participants were found to meet the inclusion criteria. The quality of evidence was high. The control group had significantly higher values for 6MWD, DLCO, and FVC compared to the ambrisentan treatment group. The rates of hospitalization and IPF worsening were considerably greater in comparison with the control group. The bosentan group exhibited significantly reduced rates of hospitalization and IPF worsening in comparison with the control group. Both drugs did not cause any raising in death or SAEs when in comparison with the control group.
The findings of this research validate the effectiveness and safety of bosentan for treating IPF patients. This medication can enhance the quality of life for individuals with IPF without causing any significant increase in SAEs. However, it does not have a notable influence on the long-term prognosis. The findings of this research do not endorse the utilization of ambrisentan in individuals diagnosed with IPF.
We design a back-illuminated p–i–n–i–n separate absorption and multiplication (SAM) AlGaN solar-blind avalanche photodiode (APD) with a low Al-content p-graded Al
x
Ga
1-x
N layer and a high/low ...Al-content AlGaN multiplication layer. Simultaneously, an III-nitride AlN/Al
0.64
Ga
0.36
N distributed Bragg reflector (DBR) structure is inserted to improve the solar-blind photoresponse for the designed APD. The simulation results show that the designed APD exhibits enhanced optoelectronic characteristics compared to the conventional APD, which is attributed to the higher holes impact ionization coefficient and generated polarization electric field in the same direction as the applied bias field of the designed APD. The designed APD exhibits significant enhanced avalanche gain and reduced avalanche breakdown voltage compared with the conventional APD.
With most eastern Chinese cities facing major air quality challenges, there is a strong need for city-scale emission inventories for use in both chemical transport modeling and the development of ...pollution control policies. In this paper, a high-resolution emission inventory (with a horizontal resolution of 3 × 3 km) of air pollutants and CO2 for Nanjing, a typical large city in the Yangtze River Delta, is developed, incorporating the best available information on local sources. Emission factors and activity data at the unit or facility level are collected and compiled using a thorough on-site survey of major sources. Over 900 individual plants, which account for 97 % of the city's total coal consumption, are identified as point sources, and all of the emission-related parameters including combustion technology, fuel quality, and removal efficiency of air pollution control devices (APCD) are analyzed. New data-collection approaches including continuous emission monitoring systems and real-time monitoring of traffic flows are employed to improve spatiotemporal distribution of emissions. Despite fast growth of energy consumption between 2010 and 2012, relatively small interannual changes in emissions are found for most air pollutants during this period, attributed mainly to benefits of growing APCD deployment and the comparatively strong and improving regulatory oversight of the large point sources that dominate the levels and spatial distributions of Nanjing emissions overall. The improvement of this city-level emission inventory is indicated by comparisons with observations and other inventories at larger spatial scale. Relatively good spatial correlations are found for SO2, NOx, and CO between the city-scale emission estimates and concentrations at nine state-operated monitoring sites (R = 0.58, 0.46, and 0.61, respectively). The emission ratios of specific pollutants including BC to CO, OC to EC, and CO2 to CO compare well to top-down constraints from ground observations. The interannual variability and spatial distribution of NOx emissions are consistent with NO2 vertical column density measured by the Ozone Monitoring Instrument (OMI). In particular, the Nanjing city-scale emission inventory correlates better with satellite observations than the downscaled Multi-resolution Emission Inventory for China (MEIC) does when emissions from power plants are excluded. This indicates improvement in emission estimation for sectors other than power generation, notably industry and transportation. A high-resolution emission inventory may also provide a basis to consider the quality of instrumental observations. To further improve emission estimation and evaluation, more measurements of both emission factors and ambient levels of given pollutants are suggested; the uncertainties of emission inventories at city scale should also be fully quantified and compared with those at national scale.
Eriocaulon buergerianum Körnicke. (Eriocaulaceae) is one of the most common and least expensive herbal medicines for eye disease. This species is facing potential threats from climate change. ...Insufficient biogeographic knowledge of this plant species can hinder its effective management for long-term population survival. We integrated ecological niche modelling (Biomod2) with 70 records of E. buergerianum and eight environmental variables to estimate changes in distribution over time. A core area Zonation algorithm was introduced to identify conservation priority areas. Our results indicate that the range of E. buergerianum will likely decrease in the future: the overall range change on average is -44.36 ± 21.56% (-3.70% to -77.73%); values of range loss and range gain are 45.79 ± 20.30% (9.29-78.19%) and 1.43 ± 1.53% (0.18-5.59%), respectively. According to conservation priority analysis, the mandatory reserve (top 5%), negotiable reserve (0.95-0.9) and partial reserve (0.9-0.8) areas are 19,799, 19,799 and 39,597 km
, respectively. The areas identified as conservation priority are located in the southeast, especially in northern Taiwan and the Wuyi Mountains. Based on these results, we suggest a re-evaluation of the threatened status of this species, with a potential upgrade to the vulnerable (VU) category. To overcome the adverse conditions faced by populations of E. buergerianum in China, we propose a multi-faceted conservation strategy involving more complete resource assessment, a monitoring system, medical research focused on revealing medicinal components or substitutes, and a regional development plan that considers both wildlife and socio-economic issues.
The controlled fabrication of actively switchable atomic-scale devices, in particular transistors, has remained elusive to date. Here, we explain the operation of an atomic-scale three-terminal ...device by a novel switching mechanism of bistable, self-stabilizing reconstruction of the electrode contacts at the atomic level: While the device is manufactured by electrochemical deposition, it operates entirely on the basis of mechanical effects of the solid−liquid interface. We analyze mechanically and thermally stable metallic junctions with a predefined quantized conductance of 1−5 G0 in experiment and atomistic simulation. Atomistic modeling of structural and conductance properties elucidates bistable electrode reconstruction as the underlying mechanism of the device. Independent room temperature operation of two transistors at low voltage demonstrates intriguing perspectives for quantum electronics and logics on the atomic scale.
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