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The improved delayed detached-eddy simulation (IDDES) method based on the shear-stress transport (SST) κ-ω turbulence model was employed to investigate the ballast height influence on aerodynamic performance at Re ​= ​9.12 ​× ​106. Both time-averaged and instantaneous slipstreams and near-wake flow structures and associated slipstream velocity distributions are compared for four cases. Results reveal that the mean lift force coefficient decreases with increasing ballast height. At the Technical Specifications for Interoperability (TSI) trackside position, the maximum slipstream velocity with a ballast height of 1.825 ​m (Case 3) is 97.4%, 15.6% and 11.7% lower than with a ballast height of 0 ​m (Case 1), 0.825 ​m (Case 2) and 2.825 ​m (Case 4), respectively. The TSI values in Case 3 ​at both the trackside and platform positions are the lowest. In the wake region, increasing the ballast height greatly constrains the outward and downward movements of vortices. The slipstream velocity in the wake region in Case 3 is the lowest among all cases. In this study, we found that Case 3 greatly decreases the slipstream velocity around the train and improves the flow structure in the wake region, which reduces the risk to workers and equipment along the railway. • The CFD results were validated with wind tunnel experiment and found good agreement. • IDDES k-w turbulence model is used to model the detailed flow field structure. • The effect of height of ballast on the slipstream and wake dynamics of train is investigated. [ABSTRACT FROM AUTHOR]

Aims: The dysregulation of TGF‐β signaling is a crucial pathophysiological process in tumorigenesis and progression. LncRNAs have diverse biological functions and are significant participants in the regulation of tumor signaling pathways. However, the clinical value of lncRNAs related to TGF‐β signaling in glioma is currently unclear. Methods: Data on glioma's RNA‐seq transcriptome, somatic mutation, DNA methylation data, and clinicopathological information were derived from the CGGA and TCGA databases. A prognostic lncRNA signature was constructed by Cox and LASSO regression analyses. TIMER2.0 database was utilized to deduce immune infiltration characteristics. "ELMER v.2" was used to reconstruct TF‐methylation‐gene regulatory network. Immunotherapy and chemotherapy response predictions were implemented by the TIDE algorithm and GDSC database, respectively. In vitro and in vivo experiments were conducted to verify the results and clarify the regulatory mechanism of lncRNA. Results: In glioma, a TGF‐β signaling‐related 15‐lncRNA signature was constructed, including AC010173.1, HOXA‐AS2, AC074286.1, AL592424.1, DRAIC, HOXC13‐AS, AC007938.1, AC010729.1, AC013472.3, AC093895.1, AC131097.4, AL606970.4, HOXC‐AS1, AGAP2‐AS1, and AC002456.1. This signature proved to be a reliable prognostic tool, with high risk indicating an unfavorable prognosis and being linked to malignant clinicopathological and genomic mutation traits. Risk levels were associated with different immune infiltration landscapes, where high risk was indicative of high levels of macrophage infiltration. In addition, high risk also suggested better immunotherapy and chemotherapy response. cg05987823 was an important methylation site in glioma progression, and AP‐1 transcription factor family participated in the regulation of signature lncRNA expression. AGAP2‐AS1 knockdown in in vitro and in vivo experiments inhibited the proliferation, migration, and invasion of glioma cells, as well as the growth of glioma, by downregulating the expression levels of NF‐κB and ERK 1/2 in the TGF‐β signaling pathway. Conclusions: A prognostic lncRNA signature of TGF‐β signaling was established in glioma, which can be used for prognostic judgment, immune infiltration status inference, and immunotherapy response prediction. AGAP2‐AS1 plays an important role in glioma progression. [ABSTRACT FROM AUTHOR]

The propagation of the weak shock wave (WSW) to the tunnel exits and their radiation as micro-pressure waves (MPWs) may cause sonic booms or structural resonance of buildings, posing potential hazards to humans, animals, and buildings in the exit's environment. The characteristics of the WSW and sonic booms of a maglev train/tube coupling model were studied based on the two-dimensional axisymmetric unsteady Reynolds average Navier–Stokes turbulence model. In the later stage of a MPW, the formation mechanism, geometry, and kinematic characteristics of compressible vortex rings (CVRs) were systematically analyzed. The inertial effect causes the initial wavefront to gradually transition from a Gaussian-shape waveform to a triangular waveform during its propagation, eventually coalescing into a WSW. The overpressure, density jump, and shock Mach number at the WSW location all increase with the increasing train speed, while the WSW thickness decreases accordingly. The formation distance of the WSW is inversely proportional to the amplitude of the initial wavefront gradient, and the WSW directly causes the occurrence of the exit sonic boom. The MPW amplitude has significant directionality with a largest value in the axial direction. Within the speed range of 450–700 km/h, the sound pressure level of the MPW exceeds the hearing threshold and even reaches the feeling threshold. The evolution of CVRs includes primary CVR, secondary CVR, and Kelvin–Helmholtz vortices. Primary CVR has the greatest impact on the axial MPW among them. The occurrence of CVRs will cause a second small noise level other than the sonic boom. [ABSTRACT FROM AUTHOR]

Coherent structures in surrounding flows around ground vehicles play an important role in characterizing their aerodynamic features. However, due to restrictions of traditional reduced-order models, extracting physically meaningful coherent structures from turbulent flows with massive separation still remains a challenging issue. The spectral proper orthogonal decomposition (SPOD), which extracts modes optimally representing the space-time flow statistics, enables the feasibility of further modeling and control of vehicle aerodynamic features. This study intends to investigate the influence of spectral estimation parameters on SPOD results, so as to serve as fundamentals for future works into this topic. The time-resolved pressure field obtained from a large-eddy simulation considering a generic high-speed train is used as the snapshot database. Spectral estimation parameters including block number, frequency resolution, and cutoff frequency are, respectively, discussed to quantify their impacts on both SPOD spectra and modes. The results reveal that, with the increasing of block number, higher reliability and accuracy of SPOD prediction can be achieved, with the block number of 20–30 that leads both requirements of efficiency and precision. The frequency axis with finer resolution reproduces more detailed spectral information, with the eigenvalue distribution and spatial distribution of mode energy under acceptable accuracy when dimensionless frequency resolution reaches 0.025. Moreover, the reducing of cutoff frequency results in increasing unresolved energy content, which will be distributed mostly near the corresponding cutoff frequency, and more minor scaled spatial structures in SPOD modes. The findings and approaches could also work as references for wider application field of SPOD approach. [ABSTRACT FROM AUTHOR]

The aerodynamic loads on the overhead bridge bottom surface induced by train passage are reported in this paper. Both moving model test and numerical simulation approaches at the 1:20 scale are used. The numerical work is validated through both mesh independence tests and comparison with experimental data. Typical pressure variation curves are plotted and compared with previous studies. The peak pressure values' dependence on the Reynolds number is considered through four sets of experiments with different train running speeds. The peak pressure coefficient distribution law for the bridge bottom surface is presented. Differences in the pressure distribution in different bridge bottom areas are explained based on more detailed flow field information. The influence of the bridge height on the aerodynamic load magnitude and time interval is presented. Moreover, the application of the CEN Standard to practical engineering issues is discussed. [ABSTRACT FROM AUTHOR]

Hypercholesterolemia drives the development of cardiovascular disease, Supplementation with probiotics that interfere with cholesterol metabolism provide a contribution to disease prevention. 54 strains with good hydrophobicity were measured bile salt hydrolase (BSH) activity and cholesterol removal ability. Evaluated the strains for probiotic potential with the intestinal colonization ability and the resistance to simulated digestion subsequently. 10 strains were finally selected for further characterization. As the potential functional strains, explored their effects on the expression of genes related to cholesterol metabolism and signaling pathways. 6 strains could regulate expression of Niemann–Pick C1-like 1 (NPC1L1) through farnesoid X receptor (FXR)/liver X receptor (LXR) pathway. Among of them, 4 strains could reduce the lipid deposition of ox-LDL-induced macrophages which had the potential abilities to improve atherosclerosis. Based on lipid-lowering abilities and common characteristics of probiotics, Lactobacillus vaginalis FN3 and Bifidobacterium animalis subsp. Lactis F1-7 could be taken as promising probiotic candidates for further in vivo studies and might have commercial value. Image 1 • 10 probiotics were obtained by measuring lipid-lowering abilities. • They had better common characteristics of probiotics. • FN3 and F1-7 could regulate expression of the NPC1L1 through FXR/LXR pathway. • They reduced the lipid deposition of ox-LDL-induced macrophages. [ABSTRACT FROM AUTHOR]

Ocean waves are one of the most promising renewable energy sources for large‐scope applications. Recently, triboelectric nanogenerator (TENG) network has been demonstrated to effectively harvest water wave energy possibly toward large‐scale blue energy. However, the absence of effective power management severely restricts the practicability of TENGs. In this work, a hexagonal TENG network consisting of spherical TENG units based on spring‐assisted multilayered structure, integrated with a power management module (PMM), is constructed for harvesting water wave energy. The output performance of the TENG network is found to be determined by water wave frequencies and amplitudes, as well as the wave type. Moreover, with the implemented PMM, the TENG network could output a steady and continuous direct current (DC) voltage on the load resistance, and the stored energy is dramatically improved by up to 96 times for charging a capacitor. The TENG network integrated with the PMM is also applied to effectively power a digital thermometer and a wireless transmitter. The thermometer can constantly measure the water temperature with the water wave motions, and the transmitter can send signals that enable an alarm to go off once every 10 s. This study extends the application of the power management module in the water wave energy harvesting. [ABSTRACT FROM AUTHOR]

Perennial bioenergy grasses can potentially replace fossil fuels and offset atmospheric CO 2 through soil C sequestration. However, limited information relevant to the impacts of bioenergy cropping on ecosystem services, especially above- and below-ground productivity and soil C sequestration is available for subtropical environments (e.g., southeastern USA). The objective of this study was to evaluate the impacts of perennial bioenergy cropping on C cycling and accumulation in the soil following four years of production in North Florida. Treatments consisted of six perennial grass species: giant reed, elephantgrass, energycane, sugarcane, sweetcane, and giant miscanthus. Elephantgrass, energycane, sweetcane, and sugarcane produced great shoot biomass (31–41 Mg ha−1) when harvested once per year. Giant reed's shoot biomass responded favorably to two harvests per year (27–43 Mg ha−1), whereas giant miscanthus did not perform well in any of the years (9–21 Mg ha−1). Additionally, giant reed, sweetcane, and giant miscanthus produced greater root biomass (9–11 Mg ha−1) compared with the other three species (2.5–3.2 Mg ha−1). Among the six grasses, sweetcane, energycane, and elephantgrass resulted in increases in soil C stocks (~15 Mg ha−1) relative to the initial level. Conversely, giant reed and giant miscanthus had no increase in soil C stock. Results suggested that interspecies differences observed in biomass yield among the six perennial bioenergy grasses could therefore affect soil C accumulation. High biomass yielding species such as sweetcane, energycane, and elephantgrass can effectively increase soil C within a few years following establishment in a subtropical environment. • Giant reed, sweetcane, sugarcane, energycane, and elephantgrass were able to produce high shoot biomass in North Florida. • Giant miscanthus could not produce comparable shoot biomass with other species in the subtropical environment. • Sweetcane, energycane, and elephantgrass exhibited significant increases in soil C stock over four growing seasons. • Sweetcane, energycane, and elephantgrass are able to provide multiple ecosystem services rapidly following establishment. [ABSTRACT FROM AUTHOR]

Dual antiplatelet therapy (DAPT) is the basis of preventing stent thrombosis and ischemic events after percutaneous coronary intervention (PCI), but prolonging the duration of DAPT will increase the risk of bleeding. The optimal duration of DAPT after PCI remains controversial at present. The purpose of this meta-analysis was to investigate the efficacy and safety of short-term DAPT in patients undergoing PCI. PubMed, Embase, Cochrane and Web of science from inception to September 2019 were systematically searched. Randomized controlled trials were included to compare short term (3 months or less) with a standard 12-months DAPT in patients undergoing PCI. Random effect model and fixed effect model wereused to calculate the risk ratio (RR) and 95% confidence interval (CI) of each endpoint. This meta-analysis included 38479 patients undergoing PCI from 8 randomized clinical trials. No difference was observed in the risk of all-cause death (RR 0.92, 95% CI 0.80–1.06, P = 0.25), cardiovascular death (RR 0.88, 0.69–1.12, P = 0.29), myocardial infarction (RR 1.05, 0.94–1.19, P = 0.38), definite or probable stent thrombosis (RR 1.05, 0.80–1.36, P = 0.73), and stroke (RR 1.02, 0.80–1.30, P = 0.89) between short term and standard DAPT. The short-term DAPT could reduce the risk of major bleeding (RR 0.67, 0.48–0.94, P = 0.02) and any bleeding (RR 0.63, 0.48-0.82, P = 0.0005) compared with 12 months of DAPT. In conclusion, the short-term DAPT can reduce the risk of bleeding compared with standard DAPT, without increasing the risk of death or ischemia (Registered by PROSPERO, CRD42020153881). [ABSTRACT FROM AUTHOR]

A new species, Uncifera motuoensis (Orchidaceae: Epidedroideae: Aeridinae) from Xizang Autonomous Region, China is described and illustrated with detailed photos and scientific illustration. Detailed morphological comparisons indicate that U. motouensis is similar to U. obtusifolia, but differs in having entire mid-lobe of lip, narrower leaf blade and wider pollinarium stipe. For the identification, a key to the known seven species of Uncifera is presented. [ABSTRACT FROM AUTHOR]

Nitrogen (N) fertilization is a key factor in determining potato (Solanum tuberosum L.) yield, especially on sandy soils. A two-year field study was conducted in the Columbia Basin region of Oregon to determine the effect of N fertilizer rates (0, 157, 280, 404, and 527 kg ha− 1) on tuber yield and quality. Elevated tuber yield and high tuber quality were associated with Castle Russet and Echo Russet, suggesting that the newly released cultivars suit the Columbia Basin region. Regardless of cultivars and years, the total and US No. 1 tuber yields increased when the N rate was 280 kg N ha− 1. Increasing N supply further did not affect or even tended to decrease potato yield especially when N was at 527 kg N ha− 1. The yield of tubers > 283 g and culls increased with increasing N rates up to 280 kg ha− 1 but then decreased at 404 kg N ha− 1 and at 527 kg N ha− 1. Moreover, the specific gravity and the fry color of potatoes were not affected by the N rate. As the petiole nutrient concentrations were associated with tuber yields, their values at the N levels of 280 to 404 kg ha− 1 might be used by producers in deciding fertilization, especially N. More data should be collected to create the critical petiole nutrient concentrations for developing management practices for these new cultivars. [ABSTRACT FROM AUTHOR]

• A modified energy method is developed to study the properties of single-walled nanotubes. • The energy of a system is expressed by the force field functions of the molecular mechanics. • The temperature-dependent elastic property and strain energy of nanotubes are obtained. • The effect of tube diameter and inversion energy on the constants of nanotubes is significant. • The temperature has a greater effect on the tensile deformation of zigzag carbon nanotubes. A modified energy method is developed to investigate the elastic properties of single-walled carbon nanotubes. The energy of a system is expressed by the force field functions of the molecular mechanics. Under the assumption of a small deformation and the principle of minimum potential energy, the system function is established. In addition to consider the change of bond stretch and bond angle, the inversion energy is also proposed in this study. Based on the established model, the closed-form expressions of temperature-dependent Young's modulus, Poisson's ratio and strain energy of armchair and zigzag carbon nanotubes are obtained. The results show that the effect of tube diameter and inversion energy on the elastic constants of carbon nanotubes (CNTs) is significant when the tube diameter is small. Under different thermal expansion coefficients, the Young's modulus of carbon nanotubes varies nonlinearly with the temperature, whereas the Poisson's ratio is insensitive to the temperature. It is also found that the temperature has a greater effect on the tensile deformation of zigzag CNTs, which provides a more accurate theoretical foundation for the tensile fracture of CNTs in a thermal environment. [ABSTRACT FROM AUTHOR]

Background: Patients with rheumatoid arthritis (RA) who have undergone total knee arthroplasty are at increased risk of requiring a blood transfusion. This study is designed to compare the effects of preemptive antifibrinolysis of single-dose and repeat-dose tranexamic acid (TXA) in in RA patients undergoing total knee arthroplasty (TKA).Methods/design: The study will be a double-blind randomized controlled trial with two parallel groups of RA patients. Group A will be given 100 ml normal saline twice daily starting from 3 days before the operation, Group B will be given TXA 1.5 g twice daily starting from 3 days before the operation. All patients will be given TXA 1.5 g 30 min before the operation. The primary outcomes will be evaluated with total blood loss and hidden blood loss. Other outcome measurements such as, fibrinolysis parameters, inflammatory factors, visual analogue scale for post-operative pain, analgesia usage, coagulation parameters, transfusion, the length of stay (LOS), total hospitalization costs, the incidence of thromboembolic events and other complications will be recorded and compared. Recruitment is scheduled to begin on 1 August 2020, and the study will continue until 31 May 2021.Discussion: In current literature there is a lack of evidence with regard to the efficacy of TXA in RA patients. The findings of this study, whether positive or negative, will contribute to the formulation of further recommendations on the use of TXA in RA patients undergoing TKA.Trial Registration: Chinese Clinical Trial Registry, ChiCTR2000029720 . Registered 14 February 2020. [ABSTRACT FROM AUTHOR]

Ocean wave energy is a promising energy source for large-scale exploitation owing to its abundant reserve and renewability. An effort is underway to develop a generator that can adapt to the ultra-low frequency of ocean wave vibration. Here, we designed a cylindrical triboelectric nanogenerator with an internal swing structure for effective water wave energy harvesting. Based on the supporting effect of the bearing component, the rotary dielectric films can be suspended over the stator electrodes, rather than coming into direct contact with them. Benefiting from the largely reduced resistance and continuous swing of an internal rotary component, the fabricated triboelectric nanogenerator can operate for about 85 s and produce over one thousand current pulses after one water wave excitation. Being agitated by a 0.033 Hz water wave (during a period of 30 s), the optimized cylindrical triboelectric nanogenerator can produce a peak power density of 231.6 mW·m−3 and an average one of 39.8 mW·m−3. Successful demonstrations of powering portable electronic devices and iron material corrosion inhibition under such simulated excitation indicate the robust capability for ultra-low-frequency water wave energy conversion. This triboelectric nanogenerator offers a new vision for efficient ultra-low-frequency wave energy harvesting with the possibility of large-scale blue energy. [ABSTRACT FROM AUTHOR]

Nicorandil effects on platelet activation and myocardial antioxidant function in patients with unstable angina were studied. A total of 157 patients with unstable angina in the First People's Hospital of Foshan were selected and divided into experimental and control group. Patients in experimental group were treated with conventional drugs and nicorandil (15 min/day), t.i.d., for 21 days as one course of treatment, while those in control group were treated with conventional drugs. After treatment, serum indexes were detected and compared between the two groups of patients. Compared with that in control group, the platelet function of patients in the experimental group was significantly improved, and there was a statistically significant difference (P<0.05). Serum anti-oxidation factors in both groups were increased after treatment, and they were increased more significantly in experimental group (P<0.05). Serum inflammatory factors, high-sensitivity C-reactive protein and matrix metalloproteinase-9, also declined significantly in the experimental group. Nicorandil reduces inflammatory response and promotes stability of myocardial function in the treatment of unstable angina. [ABSTRACT FROM AUTHOR]

Objective: To identify the prevalence of obesity, sarcopenia, sarcopenic obesity in end-stage knee osteoarthritis (KOA) patients and analyze influences of obesity and sarcopenia in the progression of KOA. Methods: A cross-sectional study was carried out among end-stage KOA patients who consecutively admitted to Orthopedic Department for TKA. We suppose that the level of decreased physical activities would be influenced by unilateral or bilateral KOA. Patient information, albumin, hemoglobin, pace, step frequency, number of comorbid conditions were collected. Bioelectrical impedance analyzer was used to analyze body composition. Obesity, sarcopenia, sarcopenic obesity rate were analyzed with accepted diagnosis criteria. Correlations between body mass index (BMI) or age and fat mass (FM), appendicular skeletal muscle mass (ASM) were analyzed. Results: 138 patients (male 30, female 108) in southwest of China including 67 patients with unilateral KOA and 71 patients with bilateral KOA were analyzed. No statistic difference was found in mean albumin, prealbumin and hematocrystallin, body composition values and number of comorbid conditions. We found that BMI was positively correlated with FM (Male: R2 = 0.7177, p < 0.0001, Female: R2 = 0.8898, p < 0.0001), ASM (Male: R2 = 0.2640, p = 0.0037, Female: R2 = 0.2102, p < 0.0001), FM index (FMI) (Male: R2 = 0.6778, p < 0.0001, Female: R2 = 0.8801, p < 0.0001), and ASM index (ASMI) (Male: R2 = 0.3600, p = 0.0005, Female: R2 = 0.4208, p < 0.0001) in end-stage KOA patients. However, age was not obviously correlated with FM or FMI (Male: FM, R2 = 0.006911, p = 0.3924; FMI, R2 = 0.7554, p = 0.0009196; Female: FM, R2 = 0.001548, p = 0.8412; FMI, R2 = 0.002776, p = 0.7822). And slightly negatively correlated with ASM (Male: R2 = 0.05613, p = 0.0136, Female: R2 = 0.01327, p = 0.5433) and ASMI (Male: R2 = 0.02982, p = 0.3615; Female: R2 = 0.03696, p = 0.0462). The prevalence of obesity, sarcopenia and obesity sarcopenia differs according to different diagnosis criteria. No difference in the occurrence rate of obesity was found between bilateral KOA and unilateral KOA patients, and occurrence rates of sarcopenia and sarcopenic obesity were statistically higher in bilateral KOA than that in unilateral KOA patients. Conclusions: Obesity, sarcopenia and sarcopenic obesity are highly prevalent in end-stage KOA patients, sarcopenic obesity are more prevalent in bilateral KOA patients than that in unilateral KOA patients. [ABSTRACT FROM AUTHOR]

Due to global warming, the Arctic sea ice extent (SIE) is rapidly decreasing each year. According to the Intergovernmental Panel on Climate Change (IPCC) climate model projections, the summer Arctic will be nearly sea-ice-free in the 2050s of the 21st century, which will have a great impact on global climate change. As a result, accurate predictions of Arctic sea ice are of significant interest. In most current studies, the majority of deep-learning-based SIE prediction models focus on one-step prediction, and they not only have short lead times but also limited prediction skill. Moreover, these models often lack interpretability. In this study, we construct the Ice temporal fusion transformer (IceTFT) model, which mainly consists of the variable selection network (VSN), the long short-term memory (LSTM) encoder, and a multi-headed attention mechanism. We select 11 predictors for the IceTFT model, including SIE, atmospheric variables, and oceanic variables, according to the physical mechanisms affecting sea ice development. The IceTFT model can provide 12-month SIE directly, according to the inputs of the last 12 months. We evaluate the IceTFT model from the hindcasting experiments for 2019–2021 and prediction for 2022. For the hindcasting of 2019–2021, the average monthly prediction errors are less than 0.21 ×106 km 2 , and the September prediction errors are less than 0.1 ×106 km 2 , which is superior to the models from Sea Ice Outlook (SIO). For the prediction of September 2022, we submitted the prediction to the SIO in June 2022, and IceTFT still has higher prediction skill. Furthermore, the VSN in IceTFT can automatically adjust the weights of predictors and filter spuriously correlated variables. Based on this, we analyze the sensitivity of the selected predictors for the prediction of SIE. This confirms that the IceTFT model has a physical interpretability. [ABSTRACT FROM AUTHOR]

The Pacific sector of the Arctic Ocean (PA, hereafter) is a region sensitive to climate change. Given the alarming changes in sea ice cover during recent years, knowledge of sea ice loss with respect to ice advection and melting processes has become critical. With satellite-derived products from the National Snow and Ice Center (NSIDC), a 38-year record (1979–2016) of the loss in sea ice area in summer within the Pacific-Arctic (PA) sector due to the two processes is obtained. The average sea ice outflow from the PA to the Atlantic-Arctic (AA) Ocean during the summer season (June–September) reaches 0.173×106 km 2 , which corresponds to approximately 34 % of the mean annual export (October to September). Over the investigated period, a positive trend of 0.004×106 km 2 yr -1 is also observed for the outflow field in summer. The mean estimate of sea ice retreat within the PA associated with summer melting is 1.66×106 km 2 , with a positive trend of 0.053×106 km 2 yr -1. As a result, the increasing trends of ice retreat caused by outflow and melting together contribute to a stronger decrease in sea ice coverage within the PA (0.057×106 km 2 yr -1) in summer. In percentage terms, the melting process accounts for 90.4 % of the sea ice retreat in the PA in summer, whereas the remaining 9.6 % is explained by the outflow process, on average. Moreover, our analysis suggests that the connections are relatively strong (R=0.63), moderate (R=-0.46), and weak (R=-0.24) between retreat of sea ice and the winds associated with the dipole anomaly (DA), North Atlantic Oscillation (NAO), and Arctic Oscillation (AO), respectively. The DA participates by impacting both the advection (R=0.74) and melting (R=0.55) processes, whereas the NAO affects the melting process (R=-0.46). [ABSTRACT FROM AUTHOR]

Background and Aims: Human bone marrow mesenchymal stem cells (hBMSCs) are important for developing a dual‐humanized mouse model to clarify disease pathogenesis. We aimed to elucidate the characteristics of hBMSC transdifferentiation into liver and immune cells. Methods: A single type of hBMSCs was transplanted into immunodeficient Fah−/− Rag2−/− IL‐2Rγc−/− SCID (FRGS) mice with fulminant hepatic failure (FHF). Liver transcriptional data from the hBMSC‐transplanted mice were analysed to identify transdifferentiation with traces of liver and immune chimerism. Results: Mice with FHF were rescued by implanted hBMSCs. Human albumin/leukocyte antigen (HLA) and CD45/HLA double‐positive hepatocytes and immune cells were observed in the rescued mice during the initial 3 days. The transcriptomics analysis of liver tissues from dual‐humanized mice identified two transdifferentiation phases (cellular proliferation at 1–5 days and cellular differentiation/maturation at 5–14 days) and ten cell lineages transdifferentiated from hBMSCs: human hepatocytes, cholangiocytes, stellate cells, myofibroblasts, endothelial cells and immune cells (T/B/NK/NKT/Kupffer cells). Two biological processes, hepatic metabolism and liver regeneration, were characterized in the first phase, and two additional biological processes, immune cell growth and extracellular matrix (ECM) regulation, were observed in the second phase. Immunohistochemistry verified that the ten hBMSC‐derived liver and immune cells were present in the livers of dual‐humanized mice. Conclusions: A syngeneic liver‐immune dual‐humanized mouse model was developed by transplanting a single type of hBMSC. Four biological processes linked to the transdifferentiation and biological functions of ten human liver and immune cell lineages were identified, which may help to elucidate the molecular basis of this dual‐humanized mouse model for further clarifying disease pathogenesis. [ABSTRACT FROM AUTHOR]

Based on the advantages of thin-walled tubes and lattice structures in energy absorption and improved crashworthiness, a hybrid structure of lattice-reinforced thin-walled tubes with different cross-sectional cell numbers and gradient densities was constructed, and a high crashworthiness absorber with adjustable energy absorption was proposed. The experimental and finite element characterization of the impact resistance of uniform density and gradient density hybrid tubes with different lattice arrangements to withstand axial compression was carried out to investigate the interaction mechanism between the lattice packing and the metal shell, and the energy absorption of the hybrid structure was increased by 43.40% relative to the sum of its individual components. The effect of transverse cell number configuration and gradient configuration on the impact resistance of the hybrid structure was investigated, and the results showed that the hybrid structure showed higher energy absorption than the empty tube, and the best specific energy absorption was increased by 83.02%; the transverse cell number configuration had a greater effect on the specific energy absorption of the hybrid structure with uniform density, and the maximum specific energy absorption of the hybrid structure with different configurations was increased by 48.21%. The gradient density configuration had a significant effect on the peak crushing force of the gradient structure. In addition, the effects of wall thickness, density and gradient configuration on energy absorption were quantitatively analyzed. This study provides a new idea to optimize the impact resistance of lattice-structure-filled thin-walled square tube hybrid structures under compressive loading through a combination of experiments and numerical simulations. [ABSTRACT FROM AUTHOR]

The pressure variations induced by a CRH380A EMU on a 2.15 m high bridge noise barrier are investigated in a field measurement. The familiar fluctuating pressure time history curves and the peak-to-peak pressure ( ΔP ) distributions attributing to the train head on the barrier surfaces are presented. A comparison of the positive head pulse pressure is made between the measurement results and the data calculated by empirical equations in EN 14067-4. Furthermore, the influences of train speed, train running lines, locations of measurement points, train marshalling length and environmental wind speed on ΔP are analysed. The results indicate as the train speed increases, the corresponding time intervals of ΔP decrease gradually, whereas their slopes become increasingly steep. For a CRH380A EMU, the aerodynamic length of the train head is between 7.63 and 7.64 m, which differs from the physical length of a realistic train with 12.00 m. Along the noise barrier from bottom to top, the ΔP values on the inner surface decrease with the increase of height, while these values on the outer surface increase. Taking the wind direction into account, the ΔP values are a little higher when the high-speed trains run against the wind direction. [ABSTRACT FROM AUTHOR]

By use of the theoretical method of density functional theory (DFT), we systemically investigate the chalcogen doped Cu 4 metal clusters (Cu 4 O, Cu 4 S, and Cu 4 Se) as catalysts for the electrochemical CO 2 reduction with toluene as solvent. These doped clusters have efficient catalytic properties which can reduce CO 2 to CH 4 and a small amount of CH 3 OH. In the case of CO 2 hydrogenation to CH 4 , the reaction barrier of the Cu 4 O cluster and Cu 4 S cluster are reduced by 0.37 eV and 0.15 eV, respectively, compared with the pristine Cu 4 cluster. The calculation results also show the overpotentials for the CO 2 hydrogenation to CH 4 in the order of Cu 4 S < Cu 4 O < Cu 4 Se. In addition, the geometry structures, the electronic properties, and the reaction free energies on the chalcogen doped Cu 4 clusters are also discussed to further reveal the reaction mechanism in the CO 2 electroreduction process. We hope that our present work will enlighten extensive studies on the modified electrode to decrease the limiting potential and provide a reference for the subsequent studies. [ABSTRACT FROM AUTHOR]

With an increase in train speed, the aerodynamic effects caused by the train could escalate, especially for a train running in a tunnel. A number of large transient pressure waves are generated owing to the confined spaces within the tunnel, resulting in possible damage to the vehicle structure and the facilities in the tunnel. Therefore, it is necessary to study the aerodynamic performance of a train running in a tunnel. A scaled moving model test system was constructed to facilitate the simulation of the aerodynamic effects caused by a train running in a tunnel. In this study, the influence of grid density, calculation time step, and turbulence model on the pressure caused by the train entering the tunnel was analyzed, which is helpful for choosing suitable values of the aforementioned parameters to simulate the aerodynamic performance of the train in the tunnel. The impacts of Reynolds number effect on the distribution of the surface pressure and peak of pressure wave along the train, and the pressure waveform were also studied through numerical simulation on three scaled model trains (full scale, 1/8, 1/20, and 1/32 scaled). The findings aid in understanding the relationship between the Reynolds and pressure amplitude, and the results of the scaled test can be applied to a full-scale train. [ABSTRACT FROM AUTHOR]

Two luminescent coordination polymers (LCPs), namely [CdL] ( 1) and [ZnL] ( 2) based on a new ligand 2-(2-methyl-benzimidazole-1-yl)-benzoic acid (HL), have been synthesized and characterized by single crystal X-ray diffraction, powder X-ray diffraction, infrared spectroscopy, elemental analysis, and thermogravimetric analysis. 1 and 2 exhibit similar 1D looped chains with different coordination modes of L. Both LCPs show strong fluorescent emission in the visible region. The fluorescence quenching response of 1 and 2 towards Fe over other metal ions in DMF has been demonstrated by quenching titrations. Thus, 1 and 2 can be used as potential and highly selective luminescent sensors for Fe ions. Graphical Abstract: [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of oblique tunnel portals on train and tunnel aerodynamics using a 1:20 scale moving model device. Transient pressure and micro-pressure waves were measured using pressure sensors as the train model travelled through various tunnel models at a speed of 350 km/h. The mitigation physical mechanism of oblique tunnel portal on the initial compression wave was explained. Experimental results showed that oblique tunnel portals had obvious mitigation effect on- the pressure gradient and micro-pressure wave induced by the train model passing through the tunnel model. A hat oblique tunnel portal combined with a buffer structure with top holes was particularly effective. [ABSTRACT FROM AUTHOR]

The effect of a free-stream turbulence intensity level on the wake dynamics of a square-back Ahmed body is modeled using the improved delayed detached eddy simulation at Re = 9.6 × 10 4 . The center of pressure, pressure gradient on the base surface, and the barycenter of the momentum deficit on the wake plane are analyzed to characterize the wake bi-modality dynamics. Given that different flow dynamics have different dominant frequencies, the spectral proper orthogonal decomposition is utilized to separate the wake bi-stability, pumping motion of the whole recirculation region, the Von Kármán vortex shedding and the shear layer instability. The results show that entrainment of the oncoming flow into the wake is enhanced, the vorticity thickness is thickened and the length of the wake recirculation region is decreased with the increasing free-stream turbulence, resulting in a lower base suction pressure and a higher level of shear stress. The frequency of the pumping motion is increased with the increase in the oncoming turbulence intensity, while the frequency of Von Kármán vortex shedding is irrespective of the level of the background turbulence. Though the correlation between the switching rate and the oncoming turbulence intensity cannot be put forward due to the relatively short numerical simulation time compared with the wind tunnel experiment, it is still known that the turbulence intensity has a positive effect on the wake bi-stability switching. [ABSTRACT FROM AUTHOR]

Long-term intensive use of mineral fertilizers in double rice-cropping systems has led to soil acidification and soil degradation. Manure fertilization was suggested as an alternative strategy to mitigate soil degradation. However, the effects of long-term mineral and manure fertilization on rice grain yield, yield stability, soil organic carbon (SOC) content, soil total nitrogen (TN) content, and the underlying mechanisms are unclear. Based on a long-term experiment established in 1981 in southern China, we compared four treatments: no fertilizer application (Control); application of nitrogen–phosphorus–potassium (NPK); NPK plus green manure in early rice (M1); and M1 plus farmyard manure in late rice and rice straw return in winter (M2). Our results showed that 37 years of NPK, M1, and M2 significantly increased rice grain yield by 54%, 46%, and 72%, and yield stability by 22%, 17%, and 9%, respectively. M1 and M2 significantly increased SOC content by 39% and 23% compared to Control, respectively, whereas there was no difference between Control and NPK. Regarding soil TN content, it was significantly increased by 8%, 46%, and 20% by NPK, M1, and M2, respectively. In addition, M2 significantly increased bacterial OTU richness by 68%, Chao1 index by 79%, and altered the bacterial community composition. Changes in soil nutrient availability and bacterial Simpson index were positively correlated with the changes in grain yield, while shifts in bacterial community were closely related to yield stability. This study provides pioneer comprehensive assessments of the simultaneous responses of grain yield, yield stability, SOC and TN content, nutrient availability, and bacterial community composition to long-term mineral and manure fertilization in a double rice-cropping system. Altogether, this study spanning nearly four decades provides new perspectives for developing sustainable yet intensive rice cultivation to meet growing global demands. [ABSTRACT FROM AUTHOR]

Background: The pathophysiology of hepatitis B-related liver cirrhosis (HBV-LC) remains unclear. This study aimed to explore the disease mechanisms using topological analysis of the miRNA/mRNA network. Methods: Paired miRNA/mRNA sequencing was performed with thirty-three peripheral blood mononuclear cell samples (LC, n = 9; chronic hepatitis B, n = 12; normal controls, n = 12) collected from a prospective cohort to identify the miRNA/mRNA network. Topological features and functional implications of the network were analyzed to capture pathophysiologically important miRNAs/mRNAs, whose expression patterns were confirmed in the validation group (LC, n = 15; chronic hepatitis B, n = 15; normal controls, n = 10), and functional potentials initiating fibrogenesis were demonstrated in vitro. Results: The miRNA/mRNA network contained 3121 interactions between 158 differentially expressed (DE) miRNAs and 442 DE-mRNAs. The topological analysis identified a core module containing 99 miRNA/mRNA interactions and two hub nodes (miR-20a-5p/miR-340-5p), which connected to 75 DE-mRNAs. The expression pattern along the disease progression of the core module was found associated with a continuous increase in wound healing, inflammation, and leukocyte migration but an inflection of immune response and lipid metabolic regulation, consistent with the pathophysiology of HBV-LC. MiR-20a-5p/miR-340-5p were found involved in macrophage polarization and hepatic stellate cell (HSC) activation in vitro (THP-1, LX-2 cell lines), and their expression levels were confirmed in the validation group independently. Conclusion: Topological analysis of the miRNA/mRNA network in HBV-LC revealed the association between fibrosis and miR-20a-5p/miR-340-5p involving initiating activations of macrophage and HSC. Further validations should be performed to confirm the HSC/macrophage activations and the interactions between miR-20a-5p/miR-340-5p and their potential targets, which may help to develop non-invasive prognostic markers or intervention targets for HBV-LC. [ABSTRACT FROM AUTHOR]

Analysis of the slipstream development around the high-speed trains in tunnels would provide references for assessing the transient gust loads on trackside workers and trackside furniture in tunnels. This paper focuses on the computational analysis of the slipstream caused by high-speed trains passing through double-track tunnels with a cross-sectional area of 100 m2. Three-dimensional unsteady compressible Reynolds-averaged Navier-Stokes equations and a realizable k-ε turbulence model were used to describe the airflow characteristics around a high-speed train in the tunnel. The moving boundary problem was treated using the sliding mesh technology. Three cases were simulated in this paper, including two tunnel lengths and two different configurations of the train. The train speed in these three cases was 250 km/h. The accuracy of the numerical method was validated by the experimental data from full-scale tests, and reasonable consistency was obtained. The results show that the flow field around the high-speed trains can be divided into three distinct regions: the region in front of the train nose, the annular region and the wake region. The slipstream development along the two sides of train is not in balance and offsets to the narrow side in the double-track tunnels. Due to the piston effect, the slipstream has a larger peak value in the tunnel than in open air. The tunnel length, train length and length ratio affect the slipstream velocities; in particular, the velocities increase with longer trains. Moreover, the propagation of pressure waves also induces the slipstream fluctuations: substantial velocity fluctuations mainly occur in front of the train, and weaken with the decrease in amplitude of the pressure wave. [ABSTRACT FROM AUTHOR]

The aerodynamic characteristics of a high-speed train in an atmospheric boundary layer are investigated in a wind tunnel. In addition, different atmospheric boundary layer simulations are performed by changing the turbulence intensity generated by a collection of spires in a wind tunnel. Turbulent flow information, measured with the Cobra probe, is used to describe the atmospheric boundary layer. Furthermore, the effect of velocity on the atmospheric boundary layer is also studied. Both the train’s unsteady aerodynamic force and surface pressure are measured at a Reynolds number of 7.5 × 10 5 , and their mean and standard deviation are used to describe and explain the effect of turbulence and observed trends with varying turbulence intensity. [ABSTRACT FROM AUTHOR]

A letter to the editor in response to an article in the previous issue of the journal on carbon emission policy of the Chinese government is presented.

Based on ab initio total energy calculations, the structural, electronic, mechanic, and magnetic properties of PdHx are investigated. It is found that bulk modulus of PdHx is larger than the metal Pd with the hydrogen storage except Pd4H2. The calculated results for the magnetic moments show that the hydrogen addition weakens the magnetic properties of the PdHx systems. A strong magneto-volume effect is found in PdHx structures as well as Pd. The transition from paramagnetism to ferromagnetism is discussed. The corresponding densities of states for both structures are also shown to understand the magnetic behaviour. [ABSTRACT FROM AUTHOR]

Since the water oxidation half‐reaction requires the transfer of multi‐electrons and the formation of O−O bond, it's crucial to investigate the catalytic behaviours of semiconductor photoanodes. In this work, a bio‐inspired copper‐bipyridine catalyst of Cu(dcbpy) is decorated on the nanoporous Si photoanode (black Si, b‐Si). Under AM1.5G illumination, the b‐Si/Cu(dcbpy) photoanode exhibits a high photocurrent density of 6.31 mA cm−2 at 1.5 VRHE at pH 11.0, which is dramatically improved from the b‐Si photoanode (1.03 mA cm−2) and f‐Si photoanode (0.0087 mA cm−2). Mechanism studies demonstrate that b‐Si/Cu(dcbpy) has improved light‐harvesting, interfacial charge‐transfer, and surface area for water splitting. More interestingly, b‐Si/Cu(dcbpy) exhibits a pH‐dependent water oxidation behaviour with a minimum Tafel slope of 241 mV/dec and the lowest overpotential of 0.19 V at pH 11.0, which is due to the monomer/dimer equilibrium of copper catalyst. At pH ∼11, the formation of dimeric hydroxyl‐complex could form O−O bond through a redox isomerization (RI) mechanism, which decreases the required potential for water oxidation. This in‐depth understanding of pH‐dependent water oxidation catalyst brings insights into the design of dimer water oxidation catalysts and efficient photoanodes for solar energy conversion. [ABSTRACT FROM AUTHOR]

Here, we realize a regulable cross-coupling reaction using alcohols as alkylating reagents to functionalize benzothiazoles. Two types of cross-coupling products are obtained with the highest isolated yields of up to 99% and 90% for alkyl- and acetyl-derived benzothiazoles, respectively, which opens up a broad research prospect for expanding alcohols as alkylating reagents. [ABSTRACT FROM AUTHOR]

In the past decade, eigenvalue optimization has gained remarkable attention in various engineering applications. One of the main difficulties with numerical analysis of such problems is that the eigenvalues, considered as functions of a symmetric matrix, are not smooth at those points where they are multiple. We propose a new explicit nonsmooth second-order bundle algorithm based on the idea of the proximal bundle method on minimizing the arbitrary eigenvalue over an affine family of symmetric matrices, which is a special class of eigenvalue function–D.C. function. To the best of our knowledge, few methods currently exist for minimizing arbitrary eigenvalue function. In this work, we apply the-Lagrangian theory to this class of D.C. functions: the arbitrary eigenvalue function λiwith affine matrix-valued mappings, where λiis usually not convex. We prove the global convergence of our method in the sense that every accumulation point of the sequence of iterates is stationary. Moreover, under mild conditions we show that, if started close enough to the minimizerx*, the proposed algorithm converges tox* quadratically. The method is tested on some constrained optimization problems, and some encouraging preliminary numerical results show the efficiency of our method. [ABSTRACT FROM PUBLISHER]

Wind speed forecasting technology is important in the field of wind power. However, the wind speed signals are always nonlinear and non-stationary so that it is difficult to predict them accurately. Aims at this challenge, a new hybrid approach has been proposed for the wind speed high-accuracy predictions based on the Secondary Decomposition Algorithm (SDA) and the Elman neural networks. The proposed SDA combines the Wavelet Packet Decomposition (WPD) and the Fast Ensemble Empirical Mode Decomposition (FEEMD), which includes twice decomposing processes as: (a) the WPD decomposes the original wind speed into the appropriate components and the detailed components; and (b) the FEEMD further decomposes the WPD generating detailed components into a number of wind speed Intrinsic Mode Functions (IMFs). The experimental results in five real forecasting cases show that: (a) the proposed hybrid WPD-FEEMD-Elman model has satisfactory performance in the multi-step wind speed predictions; and (b) the hybrid WPD-FEEMD-Elman model has improved the forecasting performance of the hybrid WPD-Elman model and the standard Elman neural networks considerably. [ABSTRACT FROM AUTHOR]

Halophilic archaeal strain XD48 was isolated from a Chinese marine solar saltern. Cells were pleomorphic, stained Gram-negative and formed red-pigmented colonies on solid media. Strain XD48 was found to be able to grow at 25-50 °C (optimum 37 °C), at 0.9-4.8 M NaCl (optimum 3.1 M NaCl), at 0-1.0 M MgCl (optimum 0.3 MgCl) and at pH 5.0-9.5 (optimum pH 6.5). The cells lysed in distilled water, and the minimal NaCl concentration to prevent cell lysis was found to be 5 % (w/v). The major polar lipids of the strain were phosphatidic acid (PA), phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulfate (PGS), sulfated galactosyl mannosyl glucosyl diether (S-TGD-1), sulfated mannosyl glucosyl diether (S-DGD-1) and six unknown glycolipids. The 16S rRNA gene and rpoB′ gene of strain XD48 were phylogenetically related to the corresponding genes of Haloarchaeobius members (92.4-93.9 and 89.6-90.5 % similarities, respectively). The DNA G + C content of strain XD48 was determined to be 65.3 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain XD48 (=CGMCC 1.12230 = JCM 18642) represents a new species of Haloarchaeobius, for which the name Haloarchaeobius amylolyticus sp. nov. is proposed. [ABSTRACT FROM AUTHOR]

Objective To preliminarily investigate the relationship between the chronic hepatitis C virus (HCV) genotypes, 2a and 1b, and thyroid hormone levels and autoantibodies. Metliods In patients who were admitted to our hospital and diagnosed with chronic hepatitis C from October 2013 to December 2014 , reverse transcription - polymerase chain reaction was performed to determine the HCV genotype. A total of 196 patients with HCV genotype 2a or 1b were enrolled as subjects. The levels of thyroid hormone and thyroid autoantibodies were determined by chemiluminescence immunoassay, and the relationship between the HCV genotype and thyroid function was analyzed. Between - group comparison of continuous data was performed by t test, and the risk factors were evaluated by logistic regression analysis. Results In the 196 patients with hepatitis C, 57.7% (n = 113) were infected with HCV -2a, and 42. 3% (n = 83) were infected with HCV-1b. There were no significant differences in levels of thyroid hormone and thyroid autoantibodies between patients with HCV-2a and HCV-1b (P >0. 05). In the 92 patients who were treated with interferon, there were no significant differences in levels of thyroid hormone and thyroid autoantibodies between patients with HCV-2a and HCV -1b (P>0.05). Logistic regression analysis showed that the genotype classification was not a risk factor for abnormal thyroid autoantibodies ( OR = 2.012, P > 0.05 ). Conclusion There is no intrinsic link between chronic HCV genotype classification and thyroid function. The genotype classification has no substantial effect on thyroid function. [ABSTRACT FROM AUTHOR]

Background: There is uncertainty about the best approaches for advanced airway management (AAM) and the effectiveness of adrenaline treatments in Out-of-hospital cardiac arrest (OHCA). This study aimed to evaluate whether AAM and adrenaline administration provided by Emergency Medical Service (EMS) can improve the outcomes of OHCA.Methods: This study was a prospective analysis of collected data based on OHCA adult patients treated by the EMS in China from January 2019 to December 2020.The patients were divided into AAM group and no AAM group, and into subgroups according to whether adrenaline was used. The outcome was rate of return of spontaneous circulation (ROSC), survival to admission and hospital discharge.Results: 1533 OHCA patients were reported. The probability of ROSC outcome and survival admission in the AAM group was significantly higher, compared with no AAM group. The probability of ROSC outcome in the AAM group increased by 66% (adjusted OR: 1.66, 95%CI, 1.02-2.71). There were no significant differences in outcomes between the adrenaline and no adrenaline groups. The combined treatment of AAM and adrenaline increased the probability of ROSC outcome by 114% (adjusted OR, 2.14, 95%CI, 1.20-3.81) and the probability of survival to admission increased by 115% (adjusted OR, 2.15, 95%CI, 1.16-3.97).Conclusions: The prehospital AAM and the combined treatment of AAM and adrenaline in OHCA patients are both associated with an increased rate of ROSC. The combined treatment of AAM and adrenaline can improve rate of survival to admission in OHCA patients. [ABSTRACT FROM AUTHOR]

Interpenetrating phase composites (IPCs) are a new type of materials with designable mechanical properties. In this work, to explore a simple, applicable, and accurate method for property designability of interpenetrated phase composites, the interaction between the matrix phase and the reinforcing phase of IPC under compressive stress is discussed, and a microstructured representative volume element is proposed for interpenetrating metal/polymer composites under compressive loading by considering the interaction of constituent phases. The stress–strain relationship of the representative volume element is established based on the iso-stress and iso-strain assumptions. Compared with the experimental results with those of interpenetrated metal/polymer composites, interpenetrated metal/metal composites, and interpenetrated metal/ceramic composites, it is shown that the analytical solutions can accurately predict the elasto-plastic compressive stress–strain curves. [ABSTRACT FROM AUTHOR]

The satellite observations unveiled that the July sea ice extent of the Arctic shrank to the lowest value, since 1979, in 2020 with a major ice retreat in the Eurasian shelf seas including Kara, Laptev, and East Siberian seas. Based on the ERA-5 reanalysis products, we explored the impacts of warm and moist air-mass transport on this extreme event. The results revealed that anomalously high energy and moisture converged into these regions in the spring months (April to June) of 2020, leading to a burst of high moisture content and warming within the atmospheric column. The convergence is accompanied by local enhanced downward longwave surface radiation and turbulent fluxes, which is favorable for initiating an early melt onset in the region with severe ice loss. Once the melt begins, solar radiation plays a decisive role in leading to further sea ice depletion due to ice–albedo positive feedback. The typical trajectories of the synoptic cyclones that occurred on the Eurasian side in spring 2020 agree well with the path of atmospheric flow. Assessments suggest that variations in characteristics of the spring cyclones are conducive to the severe melt of sea ice. We argue that large-scale atmospheric circulation and synoptic cyclones acted in concert to trigger the exceptional poleward transport of total energy and moisture from April to June to cause this record minimum of sea ice extent in the following July. [ABSTRACT FROM AUTHOR]

Establishing an intuitive link between driving factors of household energy consumption activities and inequalities is important for the understanding of household heterogeneity in energy consumption behaviours. This paper proposes a novel typology framework based on machine learning approaches and data from 3637 Chinese households in 2014 from 85 cities. Activity-based energy consumption was measured, highlighting inequalities across activities, regions and household types. The results showed significant energy consumption disparities between urban/rural and north/south households, especially in cooking, space heating and vehicle activities. By identifying driving factors of energy consumption, a new household typology classified samples into 6 (all), 6 (urban) and 7 (rural) types. Within these types, households with similar demographic structures, lifestyles and energy consumption habits were clustered. Demographic structure, region, and primary energy demand were used as the basis for the typology. The findings demonstrated how household lifestyle differences explained the cause and underlying driving factors of urban-rural energy consumption inequalities and provided suggestions for city-by-city and type-by-type measurements to support effective low-carbon transformation in cities. • Activity-based household energy consumption (HEC) is measured and calibrated. • Household energy consumption inequalities exist in urban/rural and the north/south groups. • A four-step machine-learning approach well classifies households into reasonable clusters. • Activity-based variables are driving factors for HECs in a LASSO model. • Inequality is narrowed in household clusters and type-by-type policies are needed. [ABSTRACT FROM AUTHOR]

Background/Aims: We have demonstrated that bone morphogenetic protein 9 (BMP9) is one of the most potent BMPs in regulating osteoblast differentiation of mesenchymal stem cells (MSCs) although the molecular mechanism underlying BMP9-induced osteogenesis remains to be fully elucidated. It is known that epigenetic regulations play an important role in regulating the stem cell potency and lineage commitment. Here, we investigate if the inhibition of histone deacetylases (Hdacs) affects BMP9-induced osteogenic differentiation of MSCs. Methods: Using the Hdac inhibitor trichostatin A (TSA), we assess that TSA enhances BMP9-mediated osteogenic markers and matrix mineralization in MSCs, and bone formation in mouse embryonic limb explants. Results: We find that the endogenous expression of most of the 11 Hdacs is readily detectable in MSCs. BMP9 is shown to induce most Hdacs in MSCs. We demonstrate that TSA potentiates BMP9-induced early osteogenic marker alkaline phosphatase (ALP) activity in MSCs, as well as late osteogenic markers osteopontin (OPN) and osteocalcin (OCN) and matrix mineralization. Fetal limb explant culture studies reveal that TSA potentiates BMP9-induced endochondral bone formation, possibly by expanding hypertrophic chondrocyte zone of growth plate. Conclusion: Our findings strongly suggest histone deacetylases may play an important role in fine-tuning BMP9-mediated osteogenic signaling through a negative feedback network in MSCs. Thus, Hdac inhibitors may be used as novel therapeutics for bone fracture healing. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Wind energy, as one kind of renewable and sustainable energy sources, is expected to solve the problem of energy consumption and environment deterioration. Here, an improved rotary triboelectric nanogenerator (TENG) using rabbit fur‐based soft‐contact (SCR‐TENG) with segmented structure for harvesting low‐speed wind energy is design and fabricated. The adopted soft raw‐rabbit fur shows excellent performance in triboelectrification and is beneficial to reducing frictional resistance and prolonging the lifetime of device. After 480 000 cycles, no obvious wear is observed on the dielectric film surface, and the transferred charge is not significantly attenuated. The mechanical‐to‐electrical energy conversion efficiency of 15.4% can be achieved. Moreover, self‐powered applications have been successfully demonstrated in night direction indication, insect trapping, soil moisture detection, ambient temperature and humidity detection, and signal transmission, powered by SCR‐TENG, toward smart farming. [ABSTRACT FROM AUTHOR]

Utilizing hydrogen energy produced by water electrolysis is conducive to carbon neutrality from a technological point of view. However, this perspective is restrained by the high electricity cost in commercial development. Powering electrochemical reactions by renewable electricity converted from distributed mechanical energy can lead to commercial electric energy saving and cost reduction. In this work, a self‐powered electrochemical system (SPECS) is proposed for the conversion from blue energy of ocean waves to green energy via hydrogen fuel. This system consists of triboelectric nanogenerator (TENG) devices and an electrolyzer, where the TENG devices serve as ocean wave energy harvesters for electricity generation, while the seawater‐containing electrolyzer is employed for hydrogen generation. After power management on the output of the TENGs and electrochemical reaction optimization, the system can generate hydrogen at a rate of 814.8 µL m‐2 d‐1 and a Faraday efficiency of 69.1% under ideal operation conditions, demonstrating the practical potential of the constructed system toward carbon neutralization. [ABSTRACT FROM AUTHOR]

This paper investigates the flow dynamics around a square finite wall-mounted square cylinder of two different aspect ratios (A R = H / D = 6 and 10, H and D are the height and width, respectively) under six boundary layer thickness ( δ / D = 0.5 – 4.0 , δ is the boundary layer thickness) using the improved delayed detached eddy simulation turbulence model. The Reynolds number based on the square cylinder width and incoming velocity is Re = 1.4 × 10 4 . The aerodynamic force, surface mean and fluctuating pressure, wake closure length, Reynolds stresses, turbulence production, and the anisotropy of turbulence are analyzed in detail to investigate the effect of A R and δ / D combinations. The Q-criterion vortex identification method is adopted to identify and classify the vortex structures of different A R and δ / D combinations. The parametric diagram based on A R and δ / D to predict the dipole/quadrupole wake structure proposed in Yauwenas et al. ["The effect of aspect ratio on the wake structure of finite wall-mounted square cylinders," J. Fluid Mech. 875, 929–960 (2019)] is refined based on results of the present study (quadrupole wake for A R = 6 with δ / D ≥ 1.5 and A R = 10 with δ / D ≥ 1.0). The instantaneous space–time pressure distribution along the whole span proves the existence of cellular shedding (A R = 10 for δ / D = 0.5 – 2.0), and the spectral proper orthogonal decomposition technique is adopted to investigate the cellular shedding phenomenon and its distribution. With the increase in δ / D from 2.0 to 4.0, the cellular shedding process is absent, implying the inhibitory effect of increasing boundary layer thickness on the cellular shedding. [ABSTRACT FROM AUTHOR]

Background: To evaluate whether the use of the internal target volume (ITV) delineation method improves the performance of intensity‐modulated radiotherapy (IMRT) and three‐dimensional conformal radiotherapy (3DCRT) in terms of survival, acute toxicities, and dose–volume parameters. Methods: A total number of 477 cervical cancer patients who received concurrent chemoradiotherapy (CCRT) from January 2012 to December 2016 were retrospectively analyzed. They were divided into four groups: the non‐ITV (N‐ITV) + IMRT, ITV + IMRT, N‐ITV + 3DCRT, and ITV + 3DCRT groups, with 76, 41, 327, and 33 patients, respectively. Survival analysis was performed with the Kaplan–Meier and the log‐rank tests, and acute toxicity analysis was performed with the chi‐squared test and the binary logistic regression test. Using the propensity score matching (PSM) method, 92 patients were matched among the four groups, and their dose–volume parameters were assessed with the Kruskal–Wallis method. Results: The median follow‐up time was 49 months (1–119) for overall survival (OS). The 5‐year OS rate was 66.4%. The ITV delineation method was an independent prognostic factor for OS (HR [95% CI]: 0.52 [0.27, 0.98], p = 0.044) and progression‐free survival (PFS) (HR [95% CI]: 0.59 [0.36, 0.99], p = 0.045). The ITV + IMRT group had the lowest incidence rate (22%) and the N‐ITV + IMRT group had the highest incidence rate of grade ≥3 hematological toxicity (HT) (46.1%) among the four groups. The pelvic bone marrow relative V10, V20, and V30 in the N‐ITV + IMRT group was higher than those in the ITV + IMRT and N‐ITV + 3DCRT groups (p < 0.05). Conclusions: The use of ITV for IMRT treatment planning was associated with improved overall survival and progression‐free survival, with lower HT rate. [ABSTRACT FROM AUTHOR]