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Fastener technology is a key technology of Ballastless track structure in high-speed railway, and the elastic strip is the key component to realize fastener function. To this end, a special loading fixture is fabricated to explore the performance of the elastic strip under fatigue load. The working state of the elastic strip was simulated through the fatigue testing machine, and the stress-controlled loading modes and four loading amplitudes (25±5kN, 25±7.5kN, 25±10kN, 25±12.5kN) are investigated. The pressure control method is used for fatigue tests, and the results show that: (1) As the load amplitude increases, the fatigue life decreases sharply and its decreasing speed is greater than the increasing speed of load amplitude; (2) The buckling pressure and displacement curves of the elastic strip have the characteristics of "increasing step-by-step" and "decreasing step-by-step"; (3) In the fatigue test, the attenuation of buckling pressure is 22% - 33% and the displacement at the front end of the ring is 18% - 25%; (4) According to the results, the buckling pressure curve and the displacement curve of the ring in the elastic strip are drawn, and the equations of them are fitted to estimate the service performance of the elastic strip.

ABSTRACT To investigate the hypothesis that APS can attenuate E. coli-induced microvascular dysfunction in chicken intestine, 60 0-day old male chickens were divided into three groups with 5 replications of 4 chicks. Chicken in the APS group were treated with 15 mg APS daily while the others were given 0 mg APS for 6 days. Then all 7-day old chicken were injected intraperitoneally by E. coli, except for the chicken in the control group. After 4 h, all chicken’s intestinal samples were collected to detect gene expressions involved in inflammatory factors and adhesion molecules. Results showed that APS attenuated the signs of edema and hemorrhage in 7-day old chicken intestinal mucosa which were induced by E. coli injection. Consistently, APS significantly reduced the increasing mRNA levels of inflammatory factors such as Tumor necrosis factor-a (TNF-a), interleukin (IL) -1β and inducible nitric oxide synthase (iNOS) (p

Stratification in selective college admissions persists even as colleges' criteria for evaluating merit have multiplied in efforts to increase socioeconomic and racial diversity. Middle-class and affluent families increasingly turn to privatized services, such as private college consulting, to navigate what they perceive to be a complicated and opaque application process. How independent educational consultants (IECs) advise students can thus serve as a lens for understanding how the rules of college admissions are interpreted and taught to students. Through 50 in-depth interviews with IECs, I find that IECs encourage students to be authentic by being true to themselves but that demonstrating authenticity requires attention to how one's authentic self will be perceived. Translating an authentic self into an authentic application also involves class-based and racialized considerations, particularly for Asian American students who are susceptible to being stereotyped as inauthentic. These findings suggest that efforts to improve diversity must be carefully implemented, or they risk reproducing inequality.

The species composition and abundance of the planktonic Hyperiidea and their relationship with environmental factors (depth, temperature, salinity, dissolved oxygen, turbidity and chlorophyll a concentration) were analyzed based on 4 seasonal investigations in the Beibu Gulf between 2006 and 2007. Hyperiids were represented by 82 species, 5 of which had not previously been recorded in the South China Sea. The hyperiid communities were dominated by Lestrigonus bengalensis year-round, Hyperioides sibaginis was dominant in spring, summer and autumn, and Tullbergella cuspidata became dominant in spring. Both species richness and the Shannon-Wiener diversity index increased from north to south, and from nearshore to offshore. Biodiversity was higher in some regions where the water mass was strongly influenced by the open sea or the lower salinity water off the northern sea shelf. Results of partial correlation analysis showed that species richness was positively related to depth at all times, and negatively related to temperature only in summer and winter. TWINSPAN classification indicated that the Hyperiidea community was divided into 2 groups in spring and winter (a widely distributed group and a pelagic warm-water group), and 3 groups in summer and autumn. A clear distinction between euryhaline and pelagic species can be discerned, based on different geographical distributions of water masses.

Previous studies have shown that dendritic cells (DCs) and apoptosis play a critical role in the pathogenesis of thyroid carcinoma (TC). This study was designed to investigate the expression and distribution of S-100 protein, CD83 and apoptosis-related proteins (Fas, FasL and Bcl-2) in the thyroid tissues of thyroid papillary carcinoma (TPC) and their role in TPC pathogenesis. Immunohistochemical staining techniques and other methods were used on pathological tissues of 30 patients with Thyroid papillary carcinoma (TPC) and 30 cases of thyroid follicular adenoma (TFA, as control) to detect the expression and distribution of S-100 protein , CD83, Fas, FasL and Bcl-2. A higher expression of S-100 protein in TPC (4.6±3.2%) vs. TFA (0.95±0.64%) (p

Power plants constitute roughly 40% of carbon dioxide (CO _2 ) emissions in the United States. Climate change science, air pollution regulation, and potential carbon trading policies rely on accurate, unbiased quantification of these large point sources. Two US federal agencies—the Department of Energy and the Environmental Protection Agency—tabulate the emissions from US power plants using two different methodological approaches. We have analyzed those two data sets and have found that when averaged over all US facilities, the median percentage difference is less than 3%. However, this small difference masks large, non-Gaussian, positive and negative differences at individual facilities. For example, over the 2001–2009 time period, nearly one-half of the facilities have monthly emission differences that exceed roughly ±6% and one-fifth exceed roughly ±13%. It is currently not possible to assess whether one, or both, of the datasets examined here are responsible for the emissions difference. Differences this large at the individual facility level raise concerns regarding the operationalization of policy within the United States such as the recently announced Clean Power Plan. This policy relies on the achievement of state-level CO _2 emission rate targets. When examined at the state-level we find that one-third of the states have differences that exceed 10% of their assigned reduction amount. Such levels of uncertainty raise concerns about the ability of individual states to accurately quantify emission rates in order to meet the regulatory targets.

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Abstract DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6 $$\times $$ × 6 $$\times $$ × 6 m $$^3$$ 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019–2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties.

A payload was designed and implemented to do real-time and continuous lightning detection which can be used on remote sensing satellite. The payload consists of sensor unit and electronics unit. Based on the analysis of lighting signal spectral characteristics, the sensor unit adopts ultra-narrowband filtering technology to realize lightning signal spectral filtering, and uses high frame rate area array CMOS device as photosensitive element to obtain image information. In order to reduce the complexity and hardware resources of the electronics unit, a continuous mean elimination method is used to detect lightning signals according to the instantaneous characteristics of lightning. The self-adaptive double threshold recognition method is utilized to detect the recognized lightning signal, which significantly reduces the detection time with a detection rate up to 95%. The electronics unit has the function of quick adjustment of detection threshold through instruction, which provides a more flexible application space for lightning characteristics analysis on the ground. In addition, the system can be used to detect other point or surface target by the change of optical design according to the different characteristics of the detection target, such as the large-scale fire disaster or military target.

Modern antenna arrays desire antenna apertures which can support a wide frequency range and reconfigurable polarization states. It is challenging to realize such antenna apertures with high isolation among different antenna elements when they are closely packed, particularly for wide-band (>2:1 frequency ratio) operations. In this paper, we demonstrated switchable-band antenna arrays which can be reconfigured from S to C band with an instantaneous bandwidth close to 2:1. The major novelty in this antenna array is that a new arraying technique is adopted to reduce the number of feeding ports by 50%. As a result, the isolation among antenna elements can be significantly improved, thereby increasing the overall radiation efficiency. It should be noted that vertical, horizontal and circular polarizations are supported by this antenna array when all ports are provided with appropriate phases. Herein two arrays are demonstrated. Array I is based on a fractal-shaped slot-ring structure. Each antenna element is fed by a microstrip along the diagonal direction. The common antenna aperture can be reconfigured to operate at 2.5-4.0 GHz or 4.2-7.2 GH, using PIN diode switches. Array II is extended from Array I but with an Artificial Magnetic Conductor (AMC) ground to enhance the instantaneous bandwidth to 2:1. The length of the microstrip feeding lines are reduced to enable modular design. In addition, PIN diode switches are embedded in the feeding lines to further improve the isolation and radiation efficiency. The return losses, port isolations, radiation patterns, gains, radiation efficiencies and IIP3 are simulated and measured.

ABSTRACT This study aims to investigate whether resveratrol (RES) could inhibit NF-κB activity and protect in vitro cultured chicken lymphocytes from apoptosis induced by continuous LPS stimulation. Blood lymphocytes of chickens were collected and cultured. LPS was added to the samples of treatment group, while the same volume of normal saline (NS) was supplemented to those of the control group. In the treatment groups, four different concentrations of RES (0, 20, 40, and 80 µg/ml) were admixed. Then, the following indicators were tested: lymphocyte apoptotic rate, lymphocyte viability, NF-κB activity, TNF-a level, reactive oxygen species (ROS), and expression of apoptosis-related proteins (Fas/FasL and Caspase-8). The results indicated that the application of different concentrations of RES could significantly increase the viability of lymphocytes and decrease the apoptotic rate (p

Pressurized operation is advantageous for many electrolysis and electrosynthesis technologies. The effects of pressure have been studied extensively in conventional oxygen-ion conducting solid-oxide electrochemical cells. In constrast, very few studies have examined pressurized operation in proton-conducting electroceramics. Protonic ceramics offer high proton conductivity at intermediate temperatures (∼400–600°C) that are well-matched to many important thermochemical synthesis processes. Pressurized operation can bring significant additional benefits and/or provide access to synthetic pathways otherwise unavailable or thermodynamically disfavorable under ambient conditions and in higher- or lower-temperature electrochemical devices. Here we examine pressurized steam electrolysis in protonic-ceramic unit-cell stacks based on a BaCe0.4Zr0.4Y0.1Yb0.1O3−δ (BCZYYb4411) electrolyte, a Ni–BZCYYb4411 composite negatrode (fuel electrode) and a BaCo0.4Fe0.4Zr0.1Y0.1O3−δ (BCFZY) positrode (air-steam electrode). The cells are packaged within unit-cell stacks, including metallic interconnects, current collectors, sealing glasses and gaskets sealed by mechanical compression. The assembly is packaged within a stainless steel vessel for performance characterization at elevated pressure. Protonic-ceramic electrolyzer performance is analyzed at 550°C and pressures up to 12 bara. Increasing the operating pressure from 2.1 to 12.6 bara enables a 40% overall decrease in the over-potential required to drive electrolysis at 500 mA cm−2, with a 33% decrease in the cell ohmic resistance and a 60% decrease in the cell polarization resistance. Faradaic efficiency is also found to increase with operating pressure. These performance improvements are attributed to faster electrode kinetics, improved gas transport, and beneficial changes to the defect equilibria in the protonic-ceramic electrolyte, which more than compensate for the slight increase in Nernst potential brought by pressurized operation. Electrochemical impedance spectroscopy (EIS) coupled with distribution of relaxation time (DRT) analysis provides greater insight into the fundamental processes altered by pressurized operation.

The effects of compressibility and guiding field on the Kelvin–Helmholtz (KH) instability in a double resonant surface system are numerically investigated by using a compressible magnetohydrodynamics model. The linear growth rate and the nonlinear saturation amplitude are analyzed for different parameters. A transition from double tearing modes to the KH instability occurs depending on the compressibility and guiding field with a weak magnetic shear. These results may deepen our understanding of the properties of the KH instability with double resonant surfaces in both space and laboratory plasmas.

Abstract Background Patterns of gene expression can be dramatically different between males and females of the same species, in part due to genes on sex chromosomes. Here we test for sex differences in early transcriptomic response to oxidative stress in a species which lacks heteromorphic sex chromosomes, the copepod Tigriopus californicus. Results Male and female individuals were separately exposed to control conditions and pro-oxidant conditions (hydrogen peroxide and paraquat) for periods of 3 hours and 6 hours. Variance partitioning showed the greatest expression variance among individuals, highlighting the important information that can be obscured by the common practice of pooling individuals. Gene expression variance between sexes was greater than that among treatments, showing the profound effect of sex even when males and females share the same genome. Males exhibited a larger response to both pro-oxidants, differentially expressing more than four times as many genes, including up-regulation of more antioxidant genes, heat shock proteins and protease genes. While females differentially expressed fewer genes, the magnitudes of fold change were generally greater, indicating a more targeted response. Although females shared a smaller fraction of differentially expressed genes between stressors and time points, expression patterns of antioxidant and protease genes were more similar between stressors and more GO terms were shared between time points. Conclusions Early transcriptomic responses to the pro-oxidants H2O2 and paraquat in copepods revealed substantial variation among individuals and between sexes. The finding of such profound sex differences in oxidative stress response, even in the absence of sex chromosomes, highlights the importance of studying both sexes and the potential for developing sex-specific strategies to promote optimal health and aging in humans.

In order to provide a detailed reference for the processing of high-performance Al-Li alloy, the effects of cold rolling pre-deformation on the microstructure and properties of V-1469 Al-Li alloy were investigated by Vickers hardness, tensile measurement, intergranular corrosion, electrochemical technique and electron microscopy. The results show that the mechanical properties of V-1469 Al-Li alloy can be improved by cold rolling pre-deformation treatment. When a 10% deformation was applied, the tensile strength and yield strength reached 600 MPa and 560 MPa, respectively, and the elongation remained above 7%. Moreover, cold rolling pre-deformation treatment can effectively improve the corrosion properties of V-1469 Al-Li alloy. With the increase of pre-deformation, the maximum corrosion depth and corrosion degree are decreased. In addition, with the increase of cold rolling pre-deformation, the microstructure observation shows that the precipitation of θ’ (Al2Cu) phase is inhibited, while the main hardening-phase of T1 (Al2CuLi) phase disperses homogeneously in the grain. Besides, the volume fraction of T1 phases on the stacking fault (grain boundary and sub-grain boundary) decreases and its precipitating pattern changes from continuous precipitation to discontinuous precipitation, which causes the width of the precipitate free zone (PFZ) to gradually decrease.

Mineral dust plays an important role in the climate of the Tibetan Plateau (TP) by modifying the radiation budget, cloud macro- and microphysics, precipitation, and snow albedo. Meanwhile, the TP, with the highest topography in the world, can affect intercontinental transport of dust plumes and induce typical distribution characteristics of dust at different altitudes. In this study, we conduct a quasi-global simulation to investigate the characteristics of dust source contribution and transport over the TP at different altitudes by using a fully coupled meteorology–chemistry model, the Weather Research and Forecasting model with chemistry (WRF-Chem), with a tracer-tagging technique. Generally, the simulation reasonably captures the spatial distribution of satellite-retrieved dust aerosol optical depth (AOD) at different altitudes. Model results show that dust particles are emitted into atmosphere through updrafts over major desert regions and then transported to the TP. The East Asian dust (mainly from the Gobi and Taklamakan deserts) is transported southward and is lifted up to the TP, contributing a mass loading of 50 mg m−2 at a height of 3 km and 5 mg m−2 at a height of 12 km over the northern slope of the TP. Dust from North Africa and the Middle East are concentrated over both of the northern and southern slopes below 6 km, where mass loadings range from 10 to 100 and 1 to 10 mg m−2 below 3 km and above 9 km, respectively. As the dust is transported to the north and over the TP, mass loadings are 5–10 mg m−2 above a height of 6 km. The dust mass flux carried from East Asia to the TP is 7.9 Tg yr−1, mostly occurring at heights of 3–6 km. The dust particles from North Africa and the Middle East are transported eastward following the westerly jet and then are carried into the TP at the west side with dust mass fluxes of 7.8 and 26.6 Tg yr−1, respectively. The maximum mass flux of the North African dust mainly occurs at 0–3 km (3.9 Tg yr−1), while the Middle Eastern dust occurs at 6–9 km (12.3 Tg yr−1). The dust outflow occurs on the east side (−17.89 Tg yr−1) and south side (−11.22 Tg yr−1) of the TP, with a peak value (8.7 Tg yr−1) at 6–9 km. Moreover, the dust (by mass) is concentrated within the size range of 1.25–5.0 µm and the dust (by particle number) is concentrated in the size range of 0.156–1.25 µm. Compared with other aerosols, the dust contributes to more than 50 % of the total AOD over the TP. The direct radiative forcing induced by the dust is −1.28 W m−2 at the top of the atmosphere (cooling), 0.41 W m−2 in the atmosphere (warming), and −1.68 W m−2 at the surface (cooling). Our quantitative analyses of the dust contributions from different source regions and the associated radiative forcing can help us to better understand the role of dust on the climate over the TP and surrounding regions.

Adipose tissue (AT) is a multi-depot organ in mammals. AT from various depots differs in composition and function. Revealing the composition feature of AT depots will provide valuable information for further research on the development and fat deposition patterns in buffalo. This study explored the cellular morphology and gene expression profiles of brown and beige markers in seven AT depots of fattened buffalo: three subcutaneous depots (back, sternum, and inguinal) and four visceral depots (perirenal, mesenteric, pericardial, and omental). Histological results showed unilocular adipocytes in all seven AT depots. Uncoupling protein 1 (UCP1) mRNA, a brown and beige adipocyte gene, was detected in all depots with the highest level in VAT depots, and a limited number of UCP1-positive unilocular adipocytes were observed in the three VAT depots. The mRNAs of PPARG coactivator 1 alpha (PGC1α) and transmembrane protein 26 (TMEM26), brown or beige adipocyte markers, were identified in all seven depots and were mainly expressed in VAT depots. However, the mRNA of zinc finger protein of the cerebellum 1 (ZIC1), a brown adipocyte-specific marker, was almost undetectable. Our results demonstrated that all seven AT depots are white adipose tissue (WAT), with potential function of non-shivering thermogenesis in fattened buffalo. Beige adipocytes are more active in VAT depots than in WAT depots. These results improve our knowledge on the feature of different adipose tissue depots in buffalo, which will be useful for the research of fat deposition.

ObjectiveAsian Indians are among the fastest growing United States (US) ethnic subgroups. We characterized mortality trends for leading causes of death among foreign-born and US-born Asian Indians in the US between 2005-2017.Study design and settingUsing US standardized death certificate data, we examined leading causes of death in 73,470 Asian Indians and 20,496,189 non-Hispanic whites (NHWs) across age, gender, and nativity. For each cause, we report age-standardized mortality rates (AMR), longitudinal trends, and absolute percent change (APC).ResultsWe found that Asian Indians' leading causes of death were heart disease (28% mortality males; 24% females) and cancer (18% males; 22% females). Foreign-born Asian Indians had higher all-cause AMR compared to US-born (AMR 271 foreign-born, CI 263-280; 175.8 US-born, CI 140-221; pConclusionsForeign-born Asian Indians were 2.2 times more likely to die of heart disease and 1.6 times more likely to die of cancer. Asian Indian male AMR was 49% greater than female on average, although AMR was consistently lower for Asian Indians when compared to NHWs.

Endodontics has made significant progress in regenerative approaches in recent years, thanks to advances in biologically based procedures or regenerative endodontic therapy (RET). In recent years, our profession has witnessed a clear conceptual shift in this therapy. RET was initially based on a blood clot induced by apical bleeding without harvesting the patient’s cells or cell-free RET. Later, the RET encompassed the three principles of tissue engineering, stromal/stem cells, scaffolds, and growth factors, aiming for the regeneration of a functional dentin pulp complex. The regenerated dental pulp will recover the protective mechanisms including innate immunity, tertiary dentin formation, and pain sensitivity. This comprehensive review covers the basic knowledge and practical information for translational applications of stem cell-based RET and tissue engineering procedures for the regeneration of dental pulp. It will also provide overall information on the emerging technologies in biological and synthetic matrices, biomaterials, and signaling molecules, recent advances in stem cell therapy, and updated experimental results. This review brings useful and timely clinical evidence for practitioners to understand the challenges faced for a successful cell-based RET and the importance of preserving or reestablishing tooth vitality. The clinical translation of these current bioengineering approaches will undoubtedly be beneficial to the future practice of endodontics.

We recently discovered that a rope-pulley system that mechanically coupling the arms, legs and treadmill during walking can assist with forward propulsion in healthy subjects, leading to significant reductions in metabolic cost. However, walking balance may have been compromised, which could hinder the potential use of this device for gait rehabilitation. We performed a secondary analysis by quantifying average step width, step length, and step time, and used their variability to reflect simple metrics of walking balance (n = 8). We predicted an increased variability in at least one of these metrics when using the device, which would indicate disruptions to walking balance. When walking with the device, subjects increased their average step width (p < 0.05), but variability in step width and step length remained similar (p's > 0.05). However, the effect size for step length variability when compared to that of mechanical perturbation experiments suggest a minimal to moderate disruption in balance (Rosenthal ES = 0.385). The most notable decrement in walking balance was an increase in step time variability (p < 0.05; Cohen's d = 1.286). Its effect size reveals a moderate disruption when compared to the effect sizes observed in those with balance deficits (effect sizes ranged between 0.486 to 1.509). Overall, we conclude that healthy subjects experienced minimal to moderate disruptions in walking balance when using with this device. These data indicate that in future clinical experiments, it will be important to not only consider the mechanical and metabolic effects of using such a device but also its potential to disrupt walking balance, which may be exacerbated in patients with poor balance control.

To investigate the sources and formation mechanisms of carbonaceous aerosols, a major contributor to severe particulate air pollution, radiocarbon (14C) measurements were conducted on aerosols sampled from November 2015 to November 2016 in Xi'an, China. Based on the 14C content in elemental carbon (EC), organic carbon (OC) and water-insoluble OC (WIOC), contributions of major sources to carbonaceous aerosols are estimated over a whole seasonal cycle: primary and secondary fossil sources, primary biomass burning, and other non-fossil carbon formed mainly from secondary processes. Primary fossil sources of EC were further sub-divided into coal and liquid fossil fuel combustion by complementing 14C data with stable carbon isotopic signatures. The dominant EC source was liquid fossil fuel combustion (i.e., vehicle emissions), accounting for 64 % (median; 45 %–74 %, interquartile range) of EC in autumn, 60 % (41 %–72 %) in summer, 53 % (33 %–69 %) in spring and 46 % (29 %–59 %) in winter. An increased contribution from biomass burning to EC was observed in winter (∼28 %) compared to other seasons (warm period; ∼15 %). In winter, coal combustion (∼25 %) and biomass burning equally contributed to EC, whereas in the warm period, coal combustion accounted for a larger fraction of EC than biomass burning. The relative contribution of fossil sources to OC was consistently lower than that to EC, with an annual average of 47±4 %. Non-fossil OC of secondary origin was an important contributor to total OC (35±4 %) and accounted for more than half of non-fossil OC (67±6 %) throughout the year. Secondary fossil OC (SOCfossil) concentrations were higher than primary fossil OC (POCfossil) concentrations in winter but lower than POCfossil in the warm period. Fossil WIOC and water-soluble OC (WSOC) have been widely used as proxies for POCfossil and SOCfossil, respectively. This assumption was evaluated by (1) comparing their mass concentrations with POCfossil and SOCfossil and (2) comparing ratios of fossil WIOC to fossil EC to typical primary OC-to-EC ratios from fossil sources including both coal combustion and vehicle emissions. The results suggest that fossil WIOC and fossil WSOC are probably a better approximation for primary and secondary fossil OC, respectively, than POCfossil and SOCfossil estimated using the EC tracer method.