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The modification of high-performance lithium-sulfur battery cathode have been extensively studied. Suppressing the shuttle effect of polysulfide, solving the volume expansion of sulfur and the poor electrical conductivity of sulfur are the main directions for scientists to modify the cathode. Here we prepared bismuth ferrate powder doped with different molecular percentages of strontium by sol-gel method. Compared with the unmodified cell, the capacity and cycle stability were improved by adding as-prepared material to the cathode, which indicates that bismuth ferrate doped with certain amount of strontium plays a positive role in the cathode material modification.

Lithium metal batteries (LMBs) possess large application potential for advanced rechargeable batteries due to the high energy density (> 500 Wh kg−1) and alternative cathode materials. Random Li dendrite growth caused by uneven Li+ distribution and local ion depletion near surface of Li anode induces battery failure with inferior long-term stability. Therefore, regulation of ion distribution near anode surface is essential to realize dendrite-free and uniform Li deposition. Herein, a metal-organic framework (MOF), i.e., ZIF-8, is applied to regulate Li+ solvation structure via unsaturated metal-ion sites to achieve uniform Li+ distribution and Li deposition. A stable cycling performance over 800 h for Li symmetrical cell at 3 mA cm−2 and 3 mAh cm−2 without short circuit is realized. The facilitated Li+ solvation via the adsorption effect of metal-ion sites on anions is demonstrated, which further enhances the uniform Li+ distribution near Li anode surface. This work demonstrates an effective strategy for regulating ion coordination and Li+ distribution to stabilize Li anode via MOF-based materials.

To provide high-quality wireless network multimedia services, the 4G/5G network media access control (MAC) layer has adopted the concept of the quality of service (QoS) with different traffic classification service requirements. To efficiently allocate the limited radio resources for achieving a good balance in QoS, throughput and fairness are necessary for the wireless network MAC scheduling issues. While many conventional scheduling schemes only considered one factor: rate or delay, network users might actually have different rate and delay requirements in concert. Herein, a hybrid network user satisfaction-based downlink scheduling approach, namely, max rate delay urgency first (MRDUF), is developed. The MRDUF approach simultaneously considers rate and delay requirements and adopts a hybrid strategy comprising time- and frequency-domain schedulers using two schemes, namely, the first come first serve (FCFS) and max throughput (MT), for the LTE-A downlink environment. Simulation study results have shown that our proposed approach outperforms the conventional scheduling schemes, including MT, proportional fair (PF), blind equal throughput (BET), and earliest deadline first (EDF). The benefit of MRDUF in terms of fairness of satisfaction of rate and delay is demonstrated by the simulation study.

After a large-scale earthquake, it induces a large number of building collapses and casualties, especially in urban areas. In order to make prevention and response plans before earthquakes, various earthquake loss estimation systems have been developed. The commonly used units of analysis in those systems include grid and village (or administrative district). However, grids are not consistent with streets/roads, making grid-based analyses impractical for evacuation and rescue road planning. As for village-based analyses, a unit covers large spaces and might fail to point out the precise location of collapsed buildings. Therefore, street block, which is a block surrounded by roads, is proposed by the authors as an alternative. To figure out the better analytical units, this study compared street-block-based analyses and village-based analyses. Banqiao District in Taiwan was used as a case to delineate the street blocks by roads with a width of 6 meters or above. Building collapse assessment under peak ground acceleration (PGA) of 400 Gal and 550 Gal demonstrates that street-block-based analyses outperform village-based analyses in terms of locating the collapsed buildings. Moreover, street blocks are readily available for planning evacuation or rescue roads for their consistence with the road network. Results of this study suggest that in urban areas, the higher-resolution spatial analyses of earthquake loss estimation can be made by street-block-based analyses.

After a large-scale earthquake, the road is susceptible to get blocked by liquefaction or building collapse, and that results in disaster-relief difficulty. This study adopted two earthquake loss estimation systems in Taiwan, and the risk of road blockage caused by liquefaction or building collapse was calculated separately. A new modeling was proposed, and the comparisons of the results of a single factor and that of the joint factors were made. Four scenarios of peak ground acceleration (PGA) = 250, 400, 550, 750 Gal were tested. The result shows that the probability of road blockage due to liquefaction almost reaches the maximum when PGA hits 400 Gal. On the other hand, the probability of road blockage due to building collapse increases if PGA increases. The joint probability of road blockage due to liquefaction and building collapse can improve the underestimation when using either one factor, and it can evaluate the risk more realistically. At present, there is no risk assessment modeling considering two important factors for disaster-relief road planning in Taiwan. This study provides a simple and comprehensive disaster-relief road risk assessment modeling to make better emergency rescue plans. In addition, it can provide the information for conducting seismic strengthening policy for both sides of the disaster-relief road that can reduce the risk of obstacles to disaster-relief roads.

Strangness production processes can balance natural strangeness decay in the early hadronic Universe. Comparing to the characteristic Hubble time $1/H$, the reaction rates for $\mu^\pm+\nu_{\mu}\rightarrow K^\pm$, $l^-+l^+\rightarrow\phi$, and $\pi+\pi\rightarrow K$ in sequence become slower than expansion rate at $T=33.9\,\mathrm{MeV}$, $T=25\,\mathrm{MeV}$ and $T=20\,\mathrm{MeV}$ respectively. This means that in the antibaryon annihilation epoch near to $T\simeq 40\,\mathrm{MeV}$ strangeness is in chemical equilibrium., Comment: 4 compact pages, 3 figures, Contribution to SQM2021 Online conference

Muon abundance is required for the understanding of several fundamental questions regarding properties of the primordial Universe. In this paper we evaluate the production and decay rates of muons in the cosmic plasma as a function of temperature. This allows us to determine when exactly the muon abundance disappears. When the Universe cools below the temperature $kT_\mathrm{disappear}\approx 4.135$ MeV the muon decay rate overwhelms production rates and muons vanish quasi-instantaneously from the Universe. Interestingly, we show that at $T_\mathrm{disappear}$ the muon number is nearly equal to baryon abundance., Comment: 10 pages APPB, 3 figures, Prepared for the 60th anniversary of the Cracow School of Theoretical Physics; v2 in press: typos corrected and computational details improved

Aim To compare the diagnostic performance of rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibody (anti-CCP) in the diagnosis of patients with rheumatoid arthritis (RA) in Taiwan. Methods Serum concentrations of RF and anti-CCP were measured in 246 cases, including 39 patients with RA and 207 patients with other rheumatic diseases (non-RA). The age, sex, clinical presentation, RF, anti-CCP results and the final diagnoses were recorded and analyzed. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+) and negative likelihood ratio (LR−) were calculated. Results Among all 246 patients, 39 (15.9%) were diagnosed with RA and 207 (84.1%) were diagnosed with other rheumatic diseases (non-RA). In the diagnosis of RA, the sensitivity, specificity, PPV, NPV, LR+ and LR− of the RF test were 67%, 79%, 37%, 93%, 3.12, and 0.42, respectively. The corresponding data for the anti-CCP test were 79%, 98%, 86%, 96%, 32.91 and 0.21, respectively. The presence of either anti-CCP or RF increased the sensitivity to 85%, and when they both were present, the specificity increased to 98%. Among the 39 RA patients, 26 (66.7%) tested positive for RF, and 31 (79.5%) tested positive for anti-CCP. RF was positive in two of eight anti-CCP-negative patients with RA, and anti-CCP was positive in seven of 13 RF-negative patients with RA. Conclusions The RF and anti-CCP tests are complementary, and the co-detection of these antibodies can increase the detection rate and provide important clinical value in the diagnosis of RA. Both anti-CCP and RF positivity are useful for the diagnosis of RA, and use of both tests together improves the diagnostic sensitivity.

Dry etching of Pt/Ti film was carried out using Cl2/Ar plasmas in an inductively coupled plasma (ICP) reactor. The influence of the various process parameters, such as RIE power, ICP power and Cl2/Ar gas mixing ratio, on the etch rate and selectivity of photoresist to Pt/Ti film were investigated systematically and optimized. It was revealed that the etch rate and the selectivity strongly depended on the key process parameters. The etch rate was found to increase dramatically with increasing of RIE power and ICP power. But by changing the ratio of Cl2 to the total gas, the maximum etch rate could be obtained at the proper ratio of 20%. The results also indicated too low or too high RIE power and the Cl2 ratio was detrimental to the selectivity. The optimized parameters of Pt/Ti dry etching for high etch rate and low selectivity of photoresist to Pt/Ti were obtained to be pressure: 10mT, RF power: 250W, ICP power: 0W, Cl2: 8sccm (standard cubic centimeters per minute), Ar: 32sccm.

Interaction of magnetic moment of point particles with external electromagnetic fields experiences unresolved theoretical and experimental discrepancies. In this work we point out several issues within the relativistic quantum mechanics and the QED and we describe effects related to a new covariant classical model of magnetic moment dynamics. Using this framework we explore the invariant acceleration experienced by neutral particles coupled to an external plane wave field through the magnetic moment: we study the case of ultra relativistic Dirac neutrinos with magnetic moment in the range of $10^{-11}$ to $10^{-20}$ $\mu_\mathrm{B}$; and we address the case of slowly moving neutrons. We explore how critical accelerations for neutrinos can be experimentally achieved in laser-pulse interactions. The radiation of accelerated neutrinos can serve as an important test distinguishing between Majorana and Dirac nature of neutrinos., Comment: 8 pages

Xerostomia is one of the most common acute and late complications of radiotherapy for head and neck cancer, and it affects quality of life. We conducted a prospective study to evaluate the efficacy of traditional Chinese medicine (TCM) in toxicities and quality of life during radiotherapy. Head and neck cancer patients who were scheduled for radiotherapy were checked for inclusion/exclusion criteria before enrollment. Patients in the study group (inpatients) were hospitalized in a Chinese medicine ward and received concomitant TCM intervention during radiotherapy, while those in the control group (outpatients) received only conventional cancer treatments at the Western outpatient department. The primary end point was amelioration of postradiotherapy side effects. The secondary end points were quality of life during the cancer therapy and occurrence of adverse events following the TCM treatments. Thirty inpatients and 50 outpatients completed the study. Compared to the control group, those in the TCM group had decreased severity of xerostomia. There was no treatment-related impairment of renal or hepatic function among TCM group. Although better outcomes of social contact, dyspnea, physical and emotional function, and financial problems were found in the TCM group, we need further confirmation about the impact of hospitalization itself on these results.

The aim of this retrospective study was to examine the predictors of discontinuation of anti-tumor necrosis factor (TNF) therapy due to adverse events in Chinese patients with rheumatoid arthritis (RA). Anti-TNF-related adverse events were recorded and analyzed in 217 consecutive patients with RA followed in our institution from 2003 to 2010. Time to discontinuation of anti-TNF-α therapy was estimated using survival analysis techniques. The anti-TNF agents administered were etanercept in 181 patients and adalimumab in 36 patients. The mean age at diagnosis was 45.2 ± 13.5 years, and mean age at initiation of anti-TNF therapy was 51.8 ± 13.0 years. The mean duration of anti-TNF agent use was 36.0 ± 26.5 months (range, 1.4–87.0; median, 26.4 months). Of the 217 patients, 39 (18.0 %) developed adverse events [etanercept in 34 (18.8 %] and adalimumab in 5 (13.9 %)] during the treatment period (tuberculosis in 5, bacterial infections in 19, virus infection in 7, neuropathy in 3, malignancy in 3, other drug-related events in 1, and appendicitis in 1). In patients with RA, older age (≥55 years) at initiation of anti-TNF therapy [odds ratio (OR), 3.20; 95 % confidence interval (CI), 1.67–6.20; p

In this article, based on nucleation and growth mechanism of films, different process conditions of rapid thermal annealing (RTA) had been investigated to attain different orientation and the crystallinity of PZT film. At first, the PZT films had been fabricated by magnetron sputtering on Si/SiO2/Ti/Pt substrates, then crystallized by different stepped rapid thermal annealing process. X-ray diffraction (XRD) was used to analyze the crystal structures of the films and scanning electron microscope (SEM) was used to analyze the surface morphology of the films. As a conclusion about the research is that it is good for controlling the crystallographic orientation and enhancing the crystallinity of PZT film by different stepped rapid thermal annealing process

Nanocrystalline diamond (NCD) films were prepared on polycrystalline aluminum oxide (Al2O3) substrates by microwave plasma chemical vapor deposition (MPCVD) technique using Ar/CH4/CO2 plasma. The main objective is to study the structure and mechanical properties of the NCD films. The NCD films micrograph were examined by scanning electron microscopy (SEM) and atom force microscopy (AFM). The structure and phase composition of the films were analyzed by X-ray diffraction (XRD) and visible Raman spectroscopy. Friction testing machine was used to test the friction coefficient of the films. It was found that the diamond films possess better structure and smooth surface. Compared to Al2O3 substrates, the friction coefficient of the NCD films was smaller and the wear resistance was improved significantly.

Induced pluripotent stem (iPS) cells offer a unique potential for understanding the molecular basis of disease and development. Here we have generated several human iPS cell lines, and we describe their pluripotent phenotype and ability to differentiate into erythroid cells, monocytes, and endothelial cells. More significantly, however, when these iPS cells were differentiated under conditions that promote lympho-hematopoiesis from human embryonic stem cells, we observed the formation of pre-B cells. These cells were CD45+CD19+CD10+ and were positive for transcripts Pax5, IL7αR, λ-like, and VpreB receptor. Although they were negative for surface IgM and CD5 expression, iPS-derived CD45+CD19+ cells also exhibited multiple genomic D-JH rearrangements, which supports a pre–B-cell identity. We therefore have been able to demonstrate, for the first time, that human iPS cells are able to undergo hematopoiesis that contributes to the B-cell lymphoid lineage.

Simulation of granular particles is an important tool in many fields. However, simulation of particles of complex shapes remains largely out of reach even in two-dimension. One of the major hurdles is the difficulty in representing particles in an efficient, flexible, and accurate manner. By representing particles as convex polyhedrons which are themselves the intersection of a set of half spaces, we develop a method that allows one to efficiently carry out key operations, including particle–particle and particle–container wall overlapping detection, precise identification of the overlapping region, particle shifting, particle rotation, and others. The simulation of packing 1,000 particles into a container takes only a few minutes with this approach. We further demonstrate the potential of this approach with a simulation that re-generates the “Brazil nut” phenomenon by mixing and shaking particles of two different sizes.

The differentiation of human pluripotent stem cells to the B-cell lymphoid lineage has important clinical applications that include in vitro modeling of developmental lymphogenesis in health and disease. Here, we first demonstrate the capacity of human induced pluripotent stem cells (hiPSCs) to differentiate into CD144(+)CD73(-)CD43/CD235a(-) cells, characterized as hemogenic endothelium, and show that this population is capable of differentiating to CD10(+)CD19(+) B lymphocytes. We also demonstrate that B lymphocytes generated from hiPSCs are able to undergo full VDJ rearrangement and express surface IgM (sIgM(+)), thus representing an immature B-cell subset. Efficiency of sIgM expression on the hiPSC-derived B lymphocytes (∼ 5% of CD19(+) cells) was comparable with B lymphocytes generated from human umbilical cord blood (UCB) hematopoietic progenitor cells. Importantly, when assessed by global transcriptional profiling, hiPSC-derived B-cells show a very high level of similarity when compared with their UCB-derived counterparts, such that from more than 47,000 different transcripts, only 45 were significantly different (with a criteria adjusted P value P0.05, log FC1.5 or 2.8-fold). This represents a unique in vitro model to delineate critical events during lymphogeneisis in development and lymphoid diseases such as acute lymphocytic leukemia.

Analysis of cosmic microwave background radiation fluctuations favors an effective number of neutrinos, $N_\nu>3$. This motivates a reinvestigation of the neutrino freeze-out process. Here we characterize the dependence of $N_\nu$ on the Standard Model (SM) parameters that govern neutrino freeze-out. We show that $N_\nu$ depends on a combination $\eta$ of several natural constants characterizing the relative strength of weak interaction processes in the early Universe and on the Weinberg angle $\sin^2\theta_W$. We determine numerically the dependence $N_\nu(\eta,\sin^2\theta_W)$ and discuss these results. The extensive numerical computations are made possible by two novel numerical procedures: a spectral method Boltzmann equation solver adapted to allow emerging chemical non-equilibrium, and a method to evaluate Boltzmann equation collision integrals that generates a smooth integrand., Comment: 38 pages, 14 figures

Human induced pluripotent stem cells (hiPSCs), like embryonic stem cells, are under intense investigation for novel approaches to model disease and for regenerative therapies. Here, we describe the derivation and characterization of hiPSCs from a variety of sources and show that, irrespective of origin or method of reprogramming, hiPSCs can be differentiated on OP9 stroma towards a multi-lineage haemo-endothelial progenitor that can contribute to CD144(+) endothelium, CD235a(+) erythrocytes (myeloid lineage) and CD19(+) B lymphocytes (lymphoid lineage). Within the erythroblast lineage, we were able to demonstrate by single cell analysis (flow cytometry), that hiPSC-derived erythroblasts express alpha globin as previously described, and that a sub-population of these erythroblasts also express haemoglobin F (HbF), indicative of fetal definitive erythropoiesis. More notably however, we were able to demonstrate that a small sub-fraction of HbF positive erythroblasts co-expressed HbA in a highly heterogeneous manner, but analogous to cord blood-derived erythroblasts when cultured using similar methods. Moreover, the HbA expressing erythroblast population could be greatly enhanced (44·0 ± 6·04%) when a defined serum-free approach was employed to isolate a CD31(+) CD45(+) erythro-myeloid progenitor. These findings demonstrate that hiPSCs may represent a useful alternative to standard sources of erythrocytes (RBCs) for future applications in transfusion medicine.

We perform a model independent study of the neutrino momentum distribution at freeze-out, treating the freeze-out temperature as a free parameter. Our results imply that measurement of neutrino reheating, as characterized by the measurement of the effective number of neutrinos $N_\nu$, amounts to the determination of the neutrino kinetic freeze-out temperature within the context of the standard model of particle physics where the number of neutrino flavors is fixed and no other massless (fractional) particles arise. At temperatures on the order of the neutrino mass, we show how cosmic background neutrino properties i.e. energy density, pressure, particle density, are modified in a physically consistent way as a function of neutrino mass and $N_\nu$., Comment: 12 pages, 5 figures

This study investigates how the nucleation sequences of Pt and Ru crystallites affect the structure evolutions along with the methanol electrooxidation activity of bimetallic PtRu nanoparticles (BiNPs). We found that the BiNPs crystallites would transform from cubic to tetrakaidecahedron crystals on increasing the Ru content from 0 to 54 at%. This reduces the particle size and the size distributions during the nucleation-growth of the crystal. In the meantime, the unfilled d state and the heteroatomic intermixing of Pt atoms along with the MOR reactivity of the BiNPs will be enhanced. By increasing Ru >54 at%, the BiNPs would transform into an ellipsoid-like crystallite with a Ru rich core. This is because the Pt anions would replace the metallic Ru atoms and form a discrete sub-nano Pt nuclei at the NPs surface. Consequently, the surface MOR activity of the BiNPs is substantially suppressed.