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Maximum distance separable (MDS) codes have the optimal trade-off between storage efficiency and fault tolerance, which are widely used in distributed storage systems. As typical non-MDS codes, simple regenerating codes (SRCs) can achieve both smaller repair bandwidth and smaller repair locality than traditional MDS codes in repairing single-node erasure. In this paper, we propose generalized simple regenerating codes (GSRCs) that can support much more parameters than that of SRCs. We show that there is a trade-off between sub-packetization and fault tolerance in our GSRCs, and SRCs achieve a special point of the trade-off of GSRCs. We show that the fault tolerance of our GSRCs increases when the sub-packetization increases linearly. We also show that our GSRCs can locally repair any single-symbol erasure and any single-node erasure, and the repair bandwidth of our GSRCs is smaller than that of the existing related codes.

As a special class of array codes, piggybacking codes are maximum distance separable (MDS) codes that can achieve low repair bandwidth for single-node erasure. An $(n,k,m)$ piggybacking code contains k data nodes and $r=n-k$ parity nodes, each node stores m symbols. In this paper, we propose a new piggybacking design by jointly designing piggyback functions for both data node repair and parity node repair to reduce the repair bandwidth. Our piggybacking codes can support flexible sub-packetization m with $2\leq m\leq r$ . When $m=r$ , we derive a new lower bound of repair bandwidth based on our piggybacking structure and show that this lower bound is lower than the corresponding lower bounds derived from the existing piggybacking codes for $5 < r\ll k$ . When $m < r$ , we show that our piggybacking codes have lower repair bandwidth than the existing piggybacking codes for all the evaluated high-code-rate parameters with $10\leq r\leq 20$ , $k=100$ and $m\leq 5$ . Moreover, we derive the lower bound of repair complexity defined as the number of multiplication operations required in repairing single-node erasure under general piggybacking framework and show that our codes can achieve the repair complexity lower bound, i.e., our codes have optimal repair complexity.

Conditional graph entropy is known to be the minimal rate for a natural functional compression problem with side information at the receiver. In this paper we show that it can be formulated as an alternating minimization problem, which gives rise to a simple iterative algorithm for numerically computing (conditional) graph entropy. This also leads to a new formula which shows that conditional graph entropy is part of a more general framework: the solution of an optimization problem over a convex corner. In the special case of graph entropy (i.e., unconditioned version) this was known due to Csiszár, Körner, Lovász, Marton, and Simonyi. In that case the role of the convex corner was played by the so-called vertex packing polytope. In the conditional version it is a more intricate convex body but the function to minimize is the same. Furthermore, we describe a dual problem that leads to an optimality check and an error bound for the iterative algorithm.

Let Gbe a graph and (V1,V2,⋯,Vk)be a k-partition of G. For 1⩽i0.

The utilization of face masks is an essential healthcare measure, particularly during times of pandemics, yet it can present challenges in communication in our daily lives. To address this problem, we propose a novel approach known as the human-in-the-loop StarGAN (HL–StarGAN) face-masked speech enhancement method. HL–StarGAN comprises discriminator, classifier, metric assessment predictor, and generator that leverages an attention mechanism. The metric assessment predictor, referred to as MaskQSS, incorporates human participants in its development and serves as a “human-in-the-loop” module during the learning process of HL–StarGAN. The overall HL–StarGAN model was trained using an unsupervised learning strategy that simultaneously focuses on the reconstruction of the original clean speech and the optimization of human perception. To implement HL–StarGAN, we created a face-masked speech database named “FMVD,” which comprises recordings from 34 speakers in three distinct face-masked scenarios and a clean condition. We conducted subjective and objective tests on the proposed HL–StarGAN using this database. The outcomes of the test results are as follows: (1) MaskQSS successfully predicted the quality scores of face-masked voices, outperforming several existing speech assessment methods. (2) The integration of the MaskQSS predictor enhanced the ability of HL–StarGAN to transform face-masked voices into high-quality speech; this enhancement is evident in both objective and subjective tests, outperforming conventional StarGAN and CycleGAN-based systems.

In this paper, we study a concatenate coding scheme based on sparse regression code (SPARC) and tree code for unsourced random access in massive multiple-input and multiple-output systems. Our focus is concentrated on efficient decoding for the inner SPARC with practical concerns. A two-stage method is proposed to achieve near-optimal performance while maintaining low computational complexity. Specifically, a one-step thresholding-based algorithm is first used for reducing large dimensions of the SPARC decoding, after which a relaxed maximum-likelihood estimator is employed for refinement. Adequate simulation results are provided to validate the near-optimal performance and the low computational complexity. Besides, for covariance-based sparse recovery method, theoretical analyses are given to characterize the upper bound of the number of active users supported when convex relaxation is considered, and the probability of successful dimension reduction by the one-step thresholding-based algorithm.

Abundant high-rate $(n, k)$ minimum storage regenerating (MSR) codes have been reported in the literature. However, most of them require contacting all the surviving nodes during a node repair process, resulting in a repair degree of $d=n-1$ . In practical systems, it may not always be feasible to connect and download data from all surviving nodes, as some nodes may be unavailable. Therefore, there is a need for MSR code constructions with a repair degree of $d < n-1$ . Up to now, only a few $(n, k)$ MSR code constructions with repair degree $d < n-1$ have been reported, some have a large sub-packetization level, a large finite field, or restrictions on the repair degree $d$ . In this paper, we propose a new $(n, k)$ MSR code construction that works for any repair degree $d>k$ , and has a smaller sub-packetization level or finite field than some existing constructions. Additionally, in conjunction with a previous generic transformation to reduce the sub-packetization level, we obtain an MDS array code with a small sub-packetization level and $(1+\epsilon)$ -optimal repair bandwidth (i.e., $(1+\epsilon)$ times the optimal repair bandwidth) for repair degree $d=n-1$ . This code outperforms some existing ones in terms of either the sub-packetization level or the field size.

Temporal link prediction (TLP) is an inference task on dynamic graphs that predicts future topology using historical graph snapshots. Existing TLP methods are usually designed for unweighted graphs with fixed node sets. Some of them cannot be generalized to the prediction of weighted graphs with non-fixed node sets. Although several methods can still be used to predict weighted graphs, they can only derive low-quality prediction snapshots sensitive to large edge weights but fail to distinguish small and zero weights in adjacency matrices. In this study, we consider the challenging high-quality TLP on weighted dynamic graphs and propose a novel inductive dynamic embedding aggregation (IDEA) method, inspired by the high-resolution video prediction. IDEA combines conventional error minimization objectives with a scale difference minimization objective, which can generate high-quality weighted prediction snapshots, distinguishing differences among large, small, and zero weights in adjacency matrices. Since IDEA adopts an inductive dynamic embedding scheme with an attentive node aligning unit and adaptive embedding aggregation module, it can also tackle the TLP on weighted graphs even with non-fixed node sets. Experiments on datasets of various scenarios validate that IDEA can derive high-quality prediction results for weighted dynamic graphs and tackle the variation of node sets.

By moving to millimeter wave (mmWave) frequencies, base stations (BSs) will be densely deployed to provide seamless coverage in sixth generation (6G) mobile communication systems, which, unfortunately, leads to severe cell-edge problem. In addition, with massive multiple-input-multiple-output (MIMO) antenna arrays employed at BSs, the beamspace channel is sparse for each user, and thus there is no need to serve all the users in a cell by all the beams therein jointly. Therefore, it is of paramount importance to develop a flexible clustered cell-free networking scheme that can decompose the whole network into a number of weakly interfered small subnetworks operating independently and in parallel. Given a per-user rate constraint for service quality guarantee, this paper aims to maximize the number of decomposed subnetworks so as to reduce the signaling overhead and system complexity as much as possible. By formulating it as a bipartite graph partitioning problem, a rate-constrained network decomposition (RC-NetDecomp) algorithm is proposed, which can smoothly tune the network structure from the current cellular network with simple beam allocation to a fully cooperative network by increasing the required per-user rate. Simulation results demonstrate that the proposed RC-NetDecomp algorithm outperforms existing baselines in terms of average per-user rate, fairness among users and energy efficiency.

Recently, learned heuristics have been widely applied to solve combinatorial optimization problems (e.g., traveling salesman problem (TSP)). However, the scalability of these learning-based methods hinders the applications in practical scenarios. Specifically, models pre-trained on the small-scale data generalize poorly to large-scale problems. Moreover, learning the heuristics directly for large-scale problems costs tremendous time and space. To extend the scalability of learned heuristics on TSP, we propose a Hierarchical neural framework for solving large-scale traveling salesman problems (HiTSPs) based on a divide-and-conquerstrategy. In particular, the HiTSP framework first divides the large-scale problem into small-scale subproblems by node clustering. Each subproblem is conquered by a modified pointer network learned from reinforcement learning. The tour of the original TSP is constructed by linking solutions of subproblems and optimized by a novel segmented local search algorithm. Notably, the segmented local search algorithm leverages the node clustering information to prune many unnecessary operations and significantly reduces the complexity in theory. Extensive experiments show that HiTSP outperforms state-of-the-art learning-based methods and Google OR-Tools in large-scale cases. Moreover, compared to the best heuristic algorithms, HiTSP has a significant advantage in efficiency for large-scale TSP problems.

Mixed integer linear programming (MILP) is an NP-hard problem, which can be solved by the branch and bound algorithm by dividing the original problem into several subproblems and forming a search tree. For each subproblem, linear programming (LP) relaxation can be solved to find the bound for making the following decisions. Recently, with the increasing dimension of MILPs in different applications, how to accelerate the solution process becomes a huge challenge. In this survey, we summarize techniques and trends to speed up MILP solving from two perspectives. First, we present different approaches in simplex initialization, which can help to accelerate the solution of LP relaxation for each subproblem. Second, we introduce the learning-based technologies in branch and bound algorithms to improve decision making in tree search. We also propose several potential directions and extensions to further enhance the efficiency of solving different MILP problems.

Maintaining the freshness of information in the Internet of Things (IoT) is a critical yet challenging problem. In this paper, we study cooperative data collection using multiple Unmanned Aerial Vehicles (UAVs) with the objective of minimizing the total average Age of Information (AoI). We consider various constraints of the UAVs, including kinematic, energy, trajectory, and collision avoidance, in order to optimize the data collection process. Specifically, each UAV, which has limited on-board energy, takes off from its initial location and flies over sensor nodes to collect update packets in cooperation with the other UAVs. The UAVs must land at their final destinations with non-negative residual energy after the specified time duration to ensure they have enough energy to complete their missions. It is crucial to design the trajectories of the UAVs and the transmission scheduling of the sensor nodes to enhance information freshness. We model the multi-UAV data collection problem as a Decentralized Partially Observable Markov Decision Process (Dec-POMDP), as each UAV is unaware of the dynamics of the environment and can only observe a part of the sensors. To address the challenges of this problem, we propose a multi-agent Deep Reinforcement Learning (DRL)-based algorithm with centralized learning and decentralized execution. In addition to the reward shaping, we use action masks to filter out invalid actions and ensure that the constraints are met. Simulation results demonstrate that the proposed algorithms can significantly reduce the total average AoI compared to the baseline algorithms, and the use of the action mask method can improve the convergence speed of the proposed algorithm.

Partial maximum distance separable (PMDS) codes are a kind of erasure codes where the nodes are divided into multiple groups with each forming an MDS code with a smaller code length, thus they allow repairing a failed node with only a few helper nodes and can correct all erasure patterns that are information-theoretically correctable. However, the repair of a failed node of PMDS codes still requires a large amount of communication if the group size is large. Recently, PMDS array codes with each local code being an MSR code were introduced to reduce the repair bandwidth further. However, they require extensive rebuilding access and unavoidably a significant sub-packetization level. In this paper, we first propose two constructions of PMDS array codes with two global parities that have smaller sub-packetization levels and much smaller finite fields than the existing one. One construction can support an arbitrary number of local parities and has $(1+\epsilon)$ -optimal repair bandwidth (i.e., $(1+\epsilon)$ times the optimal repair bandwidth), while the other one is limited to two local parities but has significantly smaller rebuilding access and its sub-packetization level is only 2. In addition, we present a construction of PMDS array code with three global parities, which has a smaller sub-packetization level as well as $(1+\epsilon)$ -optimal repair bandwidth, the required finite field is significantly smaller than existing ones.

Background Benzodiazepines (BZDs) are commonly prescribed as adjunctive drugs for patients with cardiovascular diseases (CVDs), particularly those who experience anxiety or insomnia. However, the relationship between the use of BZDs and incident risk of sudden cardiac arrest (SCA) has not been well investigated. In this study, we aimed to examine the association between the use of BZDs and the incident risk of SCA among patients with CVD.Method In this retrospective cohort study, a total of 74,715 eligible patients with new-onset CVD as a primary cause of hospitalization between July 2016 and August 2022 were included from the health information platform in Shenzhen, China. Among them, 61,761 BZD non-initiators were identified and matched to 12,954 BZD initiators by propensity score at a maximum ratio of 5:1. Propensity score-matched Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs).Results Over a 12-month follow-up period, 29 (2.24 per 1000 person-years) and 137 (2.22 per 1000 person-years) SCA cases occurred among propensity score-matched BZD initiators and non-initiators, respectively. Patients who initiated BZD treatment were associated with a 101% increased risk of SCA incidence compared with patients without BZD treatment (adjusted HR: 2.01, 95% CI: 1.42, 2.83). Furthermore, compared with the non-use (0 defined daily dose, DDD), the adjusted HR was 1.43 (95% CI: 1.32, 1.56) for the BZD consumption of ≤1 DDD and 2.58 (95% CI: 2.37, 2.81) for the BZD consumption of >1 DDD (Pfor trend < 0.001) within a 12-month follow-up period.Conclusion This study provides evidence that BZD initiation may be associated with an increased incident risk of SCA in patients with CVD. Our finding highlights the importance of cautious prescribing BZDs in the health management of patients with CVD.

Linear turbine cascades have been widely used to conduct fundamental and applied investigations, but only a few transient test facilities with the linear turbine cascade are available in the open literature. A novel transient test facility was presented in this paper, including detailed design and structure, and various experimental measurements (aerodynamic and thermodynamic) were conducted to verify the transient test facility’s capability. This test facility mainly includes a main air supply line (bypass line and test line), a coolant supply line, a test section, and a control system (heater and various valves). The linear cascade holds up six equally spaced cascade profiles, forming five completed cascade passages, and the center passage is used for aerodynamic and thermodynamic measurements. The aerodynamic loss and heat transfer performance were measured at various flow conditions (incidence angle, Ma, and blowing ratio (BR)). The endwall heat transfer coefficient and film cooling effectiveness were estimated by adopting a dual linear regression technique. Results indicate that the mianstream pressure and temperature present a desired step change, and remain relatively steady in the test window. The magnitudes of endwall heat transfer significantly increase as the Maex increases from 0.2 to 0.5, but the thermal load distributions remain the same. The BR is a key parameter for endwall film cooling performance, and the optimal film cooling coverage is acquired at the critical value of BR. Both insufficient and excessive coolant flowrate can result in undesirable endwall film cooling coverage, and may cause unnecessary consumption of the coolant flow.

A compact 10 MeV S-band irradiation electron linear accelerator (linac) was developed to simulate electronic radiation in outer space and perform electron irradiation effect tests on spacecraft materials and devices. According to the requirements of space environment simulation, the electron beam energy can be adjusted in the range from 3.5 to 10 MeV, and the average current can be adjusted in the range from 0.1 to 1 mA. The linac should be capable of providing beam irradiation over a large area of 1 m2with a uniformity greater than 90% and a scanning rate of 100 Hz. A novel method was applied to achieve such a high beam scanning rate by combining a kicker and a scanning magnet. Based on this requirement, a design for the 10 MeV linac is proposed with an RF power pulse repetition rate of 500 Hz; it includes a thermal cathode electron gun, a bunching-accelerating section, and a scanning transport line. The detailed physical design and dynamic simulation results of the proposed 10 MeV electron linac are presented in this paper.

Over recent decades, China has risen to a preeminent global position in both solar photovoltaic (PV) adoption and production, a feat underpinned by a suite of pivotal policy measures. With a burgeoning demand for PV systems on the horizon, there is an urgent need to reassess past policies and chart new directions. This study employs bibliometrics and content analysis to systematically scrutinize China's PV policies across distinct phases, delineating the underlying rationale and overarching evolutionary trajectory. It offers a comprehensive overview of these policies, encapsulating their metamorphosis through four discernible stages. The findings of this study shed light on a discernible policy trajectory within China's dynamic PV sector. Initially, policies were meticulously tailored to nurture domestic technological capabilities and ensure a comprehensive PV supply chain. Subsequently, the focus shifted towards the widespread application of PV technology. More recently, policies have evolved to prioritize regulatory refinement, subsidy reduction, and optimizing solar power consumption. These empirical insights underscore the pivotal role of supportive policies in propelling China's PV industry growth, with far-reaching implications for emerging sectors.

This paper proposes a novel formulation using the matrix cone programming to compute an upper bound of the Shannon capacity of graphs, which is theoretically superior to the Lovász number. To achieve this, a sequence of matrix cones is constructed by adding certain co-positive matrices to the positive semi-definite matrix cones during the matrix cone programming. We require the sequence of matrix cones to have the weak product property so that the improved result of the matrix cone programming remains an upper bound of the Shannon capacity. Our result shows that the existence of a sequence of suitable matrix cones with the weak product property is equivalent to the existence of a co-positive matrix with testable conditions. Finally, we give some concrete examples with special structures to verify the existence of the matrix cone sequence.

This paper presents a working architecture for intelligent retrieval of dynamic networked information from mobile terminals using spoken natural language queries. A very efficient dynamic keyword extraction technique is used to extract automatically limited numbers of keywords to specify the huge amount of networked information, so as to reduce the very difficult problem of recognizing unconstrained spoken natural language queries into the tractable task of spotting limited number of keywords embedded in the voice' queries. A vocabulary-flexible voice keyword spotting technique is used to handle the live, dynamic and ever-changing networked information. A client-server architecture is used to integrate the dynamic keyword extraction and voice keyword spotter modules under a mobile network environment. Very encouraging experimental results indicating the feasibility of the proposed approach have been obtained.

Plants have a close relationship with their root microbiota, which comprises a complex microbial network. Histone methylation is an important epigenetic modification influencing multiple plant traits; however, little is known about the role of plant histone methylation in the assembly and network structure of the root microbiota. In this study, we established that the rice (Oryza sativa) histone methylation regulates the structure and composition of the root microbiota, especially the hub species in the microbial network. DJ-jmj703(defective in histone H3K4 demethylation) and ZH11-sdg714(defective in H3K9 methylation) showed significant different root microbiota compared with the corresponding wild types at the phylum and family levels, with a consistent increase in the abundance of Betaproteobacteria and a decrease in the Firmicutes. In the root microbial network, 35 of 44 hub species in the top 10 modules in the tested field were regulated by at least one histone methylation-related gene. These observations establish that the rice histone methylation plays a pivotal role in regulating the assembly of the root microbiota, providing insights into the links between plant epigenetic regulation and root microbiota.

ABSTRACTAlthough the mechanism of osteoarthritis (OA) has been widely studied and the use of quercetin for OA therapy is well documented, the relevant characteristics of the microbiome and metabolism remain unclear. This study reports changes in the gut microbiota and metabolism during quercetin therapy for OA in a rat model and provides an integrative analysis of the biomechanism. In this study, the rats were categorized into 3 different groups: the OA model, quercetin treatment, and control groups. The OA rats was conducted using a monoiodoacetate (MIA) injection protocol. The rats in the quercetin group received daily intragastric administration of quercetin from day 1 to day 28. Stool samples were collected, and DNA was extracted. We used an integrated approach that combined the sequencing of whole 16S rRNA, short-chain fatty acid (SCFA) measurements and metabolomics analysis by mass spectrometry (MS) to characterize the functional impact of quercetin on the gut microbiota and metabolism in a rat model of OA. The use of quercetin partially abrogated intestinal flora disorder and reversed fecal metabolite abnormalities. Compared with the control rats, the OA rats showed differences at both the class level (Clostridia, Bacteroidia, and Bacilli) and the genus level (Lactobacillusand unidentified Ruminococcaceae). Acetic acid, propionic acid and 24 metabolites were significantly altered among the three groups. However, the changes were significantly abrogated in quercetin-treated OA rats. Consequently, this study provided important evidence regarding perturbations of the gut microbiome and the function of these changes in a potential new mechanism of quercetin treatment.

A misalignment between the combustor exit and the nozzle guide vane (NGV) platform commonly exists due to manufacturing tolerances and thermal transience. This study investigated, experimentally and computationally, the effect of the combustor-turbine misalignment on the heat transfer for an axisymmetric converging endwall with a jet purge cooling scheme at transonic conditions. The studies were conducted at engine-representative Maexit = 0.85, inlet turbulence intensity of 16%, Reexit,Cax = 1.5×106. A film cooling blowing ratio of 2.5 (design condition) and 3.5 and an engine-representative density ratio of 1.95 were used in the study. Three various step misalignments, combustor exit being 4.9% span higher than turbine inlet (backward-facing), no step (baseline), and combustor exit being 4.9% span lower than turbine inlet (forward-facing), were tested to demonstrate the misalignment effect on endwall heat transfer. Results indicated that the step misalignment affects the cooling performance by altering the interaction between the coolant and the cavity vortex, horseshoe vortex, and passage vortex. At the design blowing ratio of 2.5, the backward-facing step leads to increased coolant dissipation, causing the coolant to be later dominated by the passage vortex and leading to poor cooling performance. Meanwhile, a forward-facing step induced more coolant lift-off. At the blowing ratio of 3.5, the additional momentum ensures that enough coolant enters the passage to form a stable boundary layer. Therefore, the step misalignment no longer has a first-order effect.

The stability of congestion control protocols is of great concern in modern computer networks. In particular, the problem of local stability of a congestion control protocol over a general topology with link delay is not yet completely answered. This paper works on this problem. We consider a particular class of link static congestion control protocols in general networks. In pursuit of a distributed stability certificate, we first revisit and extend the classical results. Thereafter, we propose and derive a Gershgorin type stability certificate for this class of protocols. This result is further substantiated by a flow-level simulation.

It is of great significance to design highly active and stable catalysts for CO oxidation. Herein, a Pt/In–SnO2catalyst was firstly fabricated viaa facile hydrothermal reaction coupled with photoreduction strategy, achieving 1 vol% of CO totally oxidized at just 145 °C, over 200 °C lower than that of Pt/SnO2. Moreover, Pt/In–SnO2demonstrates superior catalytic stability and recyclability under both dry and humid conditions. Incorporation of In cations results in marked structure distortion of SnO2, promoting the formation of oxygen vacancies and enhancing the concentration and mobility of reactive oxygen species. Abundant Pt sites over Pt/In–SnO2further accelerate CO adsorption and activation. Density functional theory results prove that the energy barrier of CO oxidation reduces from 0.85 to 0.75 eV after In doping and the produced CO2can desorb spontaneously from the catalyst surface, which accelerates the CO oxidation process. This work provides new ideas for designing robust catalysts for low-temperature CO elimination.

Space-air-ground integrated network (SAGIN) is envisioned as a promising solution to provide cost-effective, large-scale, and flexible wireless coverage and communication services. Since realworld deployment for testing of SAGIN is difficult and prohibitive, an efficient SAGIN simulation platform is requisite. In this article, we present our developed SAGIN simulation platform which supports various mobility traces and protocols of space, aerial, and terrestrial networks. Centralized and decentrallized controllers are implemented to optimize the network functions such as access control and resource orchestration. In addition, various interfaces extend the functionality of the platform to facilitate user-defined mobility traces and control algorithms. We also present a case study where highly mobile vehicular users dynamically choose different radio access networks according to their quality of service (QoS) requirements.

Barocaloric (BC) materials are a type of promising solid-state refrigerant that can be used in future refrigerators. Besides the routine pressure-driven lattice entropy change, spin or polar degrees of freedom often make considerable contributions. Relatively, little attention has been paid to the electronic contribution. Here we demonstrate a sizable electronic entropy change under pressure in hexagonal Ni1−xFexS due to the remarkable modification of its electronic structure. Accordingly, the total entropy change reaches 52.8 J kg−1K−1under only 100 MPa, which places Ni1−xFexS among the giant BC materials. Again, because of the electronic contribution, the thermal conductivity of Ni1−xFexS is higher than the reported values of other giant BC materials, which can boost the cooling efficiency. Our work would inspire the study of the giant BC effect with good thermal conductance in a wide range of electronic phase transition materials.

Peanut (Arachis hypogaea L.) is an important source of edible vegetable oils and plant proteins globally. However, the complex mechanisms regulating the oil and protein contents of peanut seeds remain unclear. Here, comparative broad-target metabolomics and quantitative lipidomics, together with transcriptome analysis, of peanut seeds at four developmental stages from the high-oil content variety “YH15” and high-protein content variety “KB008” were performed to search for oil and protein content control genes. A total of 984 differential metabolites, including 128 amino acids and derivatives and 310 differentially accumulated lipids, were identified between “YH15” and “KB008” in four seed developmental stages. The weighted gene coexpression network analysis and module–trait relationship analysis revealed that MEbrown, MEyellow, and MEturquoise modules were key contributors to the quality discrepancies observed between “YH15” and “KB008.” Crucial genes potentially regulating the differences in oil and protein contents between “YH15” and “KB008” were identified within the aforementioned three modules, including genes involved in amino acid synthesis and degradation, nitrogen allocation, triglyceride synthesis and degradation, and fatty acid synthesis and degradation, as well as transcription factors. Overall, this study provides valuable insights into the molecular regulation of oil and protein contents in peanut seeds and may help cultivate specialized peanut varieties with enhanced nutritional and economic values.

Modern developments in bone tissue engineering focus on designing biomimetic materials that exhibit suitable mechanical and physiochemical properties. In this study, we present the development of a new biomaterial scaffold using a newly constructed polymer that contains bisphosphonate in combination with gelatin (GAT). To achieve scaffolding, a chemical grafting technique was used to develop risedronate (RS)-functionalized polycaprolactone (PCL-RS). The freeze-casting process was used to construct the porous PCL-RS/GAT scaffold after incorporating gelatin into the PCL-RS polymer solution. A scaffold with pores that are in perfect position and a porosity of 81.84% was successfully acquired. The biodegradability assessment, 48% of its early weight was lost after five weeks. The PCL-RS/GAT scaffold exhibited an elastic modulus of 32.01 MPa and a tensile strength of 3.9 MPa. The MTT analysis showed the PCL-RS/GAT favorable cytocompatibility with rat bone marrow-derived mesenchymal stem cells (BM-MSC). In addition, the cells cultured in the PCL-RS/GAT scaffold exhibited the greatest ALP activity and mineralization. The RT-PCR test results indicated that the PCL-RS/GAT scaffold had a high RUNX2, COL 1A1, and OCN gene expression, suggesting a strong osteoinductive capacity. The results indicate that the PCL-RS/GAT scaffold is a suitable biomimetic platform for tissue engineering in bone.

Developing BiVO4photoanode with efficient carrier transfer and fast water oxidation kinetics is the permanent pursuit to achieve the state-of-art solar-driven photoelectrochemical (PEC) water splitting. The capacity to increase the PEC activity of BiVO4by loading oxygen evolution co-catalysts (OECs) has been proven, however it suffers from sluggish charge carriers dynamics brought on by the complicated interface between BiVO4and OECs as well as poor long-term durability. Herein, we connected OECs (NiFeOx) and photoanode with a Al-O bridge for bettering the PEC performance of BiVO4. The Al-O bridge served as a channel to extract hole from BiVO4to NiFeOx, thus boosting charge carriers′ separation and preventing BiVO4from photo-corrosion. The Al-O bridging photoanode (NiFeOx/Al2O3/BiVO4) demonstrated a high photocurrent density of 5.87 mA/cm2at 1.23 V vs. RHE and long-term photostability in comparison to NiFeOx/BiVO4photoanode. This study proposes a unique technique to boost charge carriers′ separation between BiVO4and OECs for high-efficiency solar-driven PEC water splitting.

Patients who undergo primary total hip (THA) and knee (TKA) arthroplasty show better clinical outcomes, improved quality of life and increased participation in leisure activities; however, the differences between primary THA and TKA in older patients are unknown. The aim of the study was to compare the Western Ontario and McMasters University osteoarthritis index (WOMAC) scores and changes in WOMAC scores, the Medical Outcomes study 12-item short-form version 2 (SF-12) mental and physical health scales, satisfaction and frequency of participation in leisure activities in older osteoarthritis patients with a mean age of 67.9 ± 10.6 years who underwent primary THA and TKA. Data from 170 THA and 169 TKA patients were collected 1 week preoperatively through self-reporting of WOMAC scores and SF-12. These parameters, level of satisfaction and frequency of participation in leisure activities were collected 1 year postoperatively by self-reporting questionnaires. The THA group of patients showed better WOMAC scores (P< 0.05), changes in WOMAC scores (P< 0.05), physical component summary (PCS) of SF-12 (P< 0.01) and changes in PCS scores (P< 0.01) compared with the TKA group. In addition, the THA patients showed higher overall satisfaction (91.90% vs. 83.60%), pain relief satisfaction (87.20% vs. 77.40%) and functional improvement satisfaction (90.10% vs. 83.08%) in comparison with the TKA patients. Furthermore, a higher frequency of participation in leisure activities was achieved in THA patients, except for intellectual leisure activities. These findings suggest that primary THA provides superior clinical outcomes, quality of life, satisfaction, and participation in leisure activities compared with primary TKA in older patients. Bei Patienten, die sich einer primären THA- bzw. TKA („total hip arthroplasty“ bzw. „total knee arthroplasty“) unterziehen, zeigen sich bessere klinische Ergebnisse, eine verbesserte Lebensqualität und eine erhöhte Teilnahme an Freizeitaktivitäten; die Unterschiede zwischen primärer THA und TKA bei älteren Patienten sind jedoch unbekannt. Ziel der Studie war es, die Therapieergebnisse nach primärer THA und TKA bei älteren Arthrosepatienten (Durchschnittsalter 67,9 ± 10,6 Jahre) vergleichend zu überprüfen anhand des WOMAC(Western Ontario und McMasters University Osteoarthritis)-Index, der Veränderungen in der WOMAC-Scores, des für die Medical Outcomes Study entwickelten SF-12 (12-Item Short Form Health Survey; Kurzform), Skalen für mentale und physische Gesundheit und Teilhabe an Freizeitaktivitäten. Die Daten von 170 THA- und 169 TKA-Patienten wurden eine Woche präoperativ mittels WOMAC-Scores und SF-12 durch Selbstauskunft erhoben. Diese Parameter, der Grad der Zufriedenheit und die Häufigkeit der Teilnahme an Freizeitaktivitäten, wurden ein Jahr nach der Operation durch Selbstauskunft erneut erhoben. Die THA-Patientengruppe zeigte im Vergleich zur TKA-Gruppe bessere Werte im WOMAC-Index (p< 0,05) und bei den WOMAC-Veränderungen (p< 0,05) sowie in der PCS(„physical component summary“)-Zusammenfassung des SF-12 (p< 0,01). Darüber hinaus stellten sich bei THA-Patienten im Vergleich zu TKA-Patienten eine höhere Gesamtzufriedenheit (91,9 vs. 83,60 %), Schmerzlinderung (87,20 vs. 77,40 %) und funktionelle Verbesserung (90,1 vs. 83,0 8%) dar. Ferner wurde (mit Ausnahme von intellektuellen Beschäftigungen) bei den Patienten der THA-Gruppe eine höhere Häufigkeit der Teilnahme an Freizeitaktivitäten erreicht. Diese Ergebnisse deuten darauf hin, dass die primäre THA im Vergleich mit einer primären TKA bei älteren Arthrosepatienten zu einem besseren klinischem Ergebnis führt und zu besseren Resultaten hinsichtlich Lebensqualität, Zufriedenheit und Teilnahme an Freizeitaktivitäten.

Triterpenic acids (TAs) commonly found in the plant kingdom are one of the most important natural ingredients owing to their various pharmacological activities. However, the determination of TAs through a rapid and efficient analysis method still remains a significant challenge because their isomers coexist in many plant samples. Herein we established a quick and sensitive determination approach for five TAs by pre-column derivatization coupled with HPLC-fluorescence detection, using 2-(5H-benzo[a]-carbazol-11(6H)-yl) ethyl hydrazine-carboxylate (BCEHC) as the labeling reagent. In addition, the relationship between the labeling reagent and the separation of TAs was further investigated by using another labeling reagent 2-(12-benzo[b]acridin-5-(12H)-yl)-acetohydrazide (BAAH) as a reference. The results of the method validations showed that both BCEHC and BAAH had good linearity with R2≥ 0.9907 and R2≥ 0.9998, exhibiting their own advantages at the same time. For five TA standards, BCEHC had lower limits of detection (0.42–1.35 μg L−1) while BAAH had a shorter retention time. Both labeling reagents can favorably satisfy the requirement of rapid determination of TAs. BCEHC was also applied to detect TAs in Caragana korshinskiiKom. (CK) exhibiting reliable outcomes. It has been verified that there are some TAs in the flowers, leaves and bark of CK. Moreover, asiatic acid and oleanolic acid are the only TAs that exist in every part of it.

Because of its cost-effective and on-demand deployment, low-altitude aerial base stations (BSs) are capable of providing emergency communication services in many scenarios. This letter investigates the security issue in emergency communications where the aerial BS is deployed optimally to serve ground users in the presence of an eavesdropper. We aim to maximize the probability of non-zero secrecy capacity to improve the possibility of physical-layer security transmission via the optimal placement of the aerial BS. The resulting nonconvex optimization problem will be simplified based on its geometric properties and equivalent transformation. The simplified problem will then be solved by using semidefinite relaxation. Numerical results show that the optimal placement of the aerial BS can significantly improve the probability of non-zero secrecy capacity.

To ensure the durability and reliability of gas turbine, film cooling has been integrated into the design of the modern gas turbine vane endwall, especially for the first-stage vane endwall. Percussion laser drilling has been a very attractive technique used to drill holes in aero-engine hot components, due to its capability of drilling on a thermal barrier coated-superalloy in milliseconds. It should be noticed that micro-geometric deviations often exist in the resulting holes manufactured by laser drilling. However, most of the investigations in the literature treated the aleatory geometric imperfections as deterministic or ideal cases, which imported an uncertainty bias to life prediction. Therefore, a detailed uncertainty quantification analysis is performed to quantify the impacts of laser drilling imperfections on the endwall cooling performance in this article. This article conducted a dual non-deterministic analysis to analyze the cooling performance robustness of a double-row film holes scheme employed in a high-pressure turbine nozzle guide vane, subjecting to the variability of film hole geometric parameters set by manufacturing deviation range. First, to evaluate the impact of laser drilling imperfections on the endwall cooling performance, a conical nozzle film hole imperfection model is proposed to parameterize the real laser drilled hole. Then, a fundamental uncertainty quantification framework, which combines the conical nozzle parameterized model, non-intrusion Polynomial Chaos UQ methodology, and k-Nearest Neighbor clustering algorithm, is built to quantify the cooling performance while geometric parameters of all film holes are consistent. The UQ results show that the likelihood of all holes being on the edge of their tolerance range increases dramatically. Large variations in mass flow ratio and film cooling effectiveness were observed. Mass flow ratios ranged from 0.51% to 2.31% (μ ± 3σ), where the baseline MFR was 1.27%. The standard deviation of adiabatic effectiveness was up to 0.2. An additional consideration to be made is that for a more real-life scenario, the geometric parameters of all film holes are not identical. A flow parameter dimensionality reduction UQ approach (FPDR), which transforms the deviations of multiple geometric parameters into the fluctuations of several key flow parameters, is proposed to address the curse of dimensionality phenomenon in predicting the cooling performance under uncertain conditions of inconsistent film hole imperfection characteristic parameters. The results show that the fluctuation ranges of MFR and adiabatic cooling effectiveness under uncertain conditions of inconsistent film hole parameters are significantly reduced, less than one-fourth and one-fifth of the fluctuation ranges under conditions of consistent film hole parameters. The developed uncertainty quantification platform can provide a useful tool to evaluate the cooling performance robustness of advanced cooling systems with multi-row cylindrical cooling holes, considering laser drill imperfection.

ABSTRACTIntroduction: Cartilage tissue engineering has rapidly developed in recent decades, exhibiting promising potential to regenerate and repair cartilage. However, the origin of a large amount of a suitable seed cell source is the major bottleneck for the further clinical application of cartilage tissue engineering. The use of a monoculture of passaged chondrocytes or mesenchymal stem cells results in undesired outcomes, such as fibrocartilage formation and hypertrophy. In the last two decades, co-cultures of chondrocytes and a variety of mesenchymal stem cells have been intensively investigated in vitroand in vivo, shedding light on the perspective of co-culture in cartilage tissue engineering.Areas covered: We summarize the recent literature on the application of heterologous cell co-culture systems in cartilage tissue engineering and compare the differences between direct and indirect co-culture systems as well as discuss the underlying mechanisms.Expert opinion: Co-culture system is proven to address many issues encountered by monocultures in cartilage tissue engineering, including reducing the number of chondrocytes needed and alleviating the dedifferentiation of chondrocytes. With the further development and knowledge of biomaterials, cartilage tissue engineering that combines the co-culture system and advanced biomaterials is expected to solve the difficult problem regarding the regeneration of functional cartilage.

Our previous high-throughput sequencing indicated that rno-miR-1298 was down-regulated in ischemia-reperfusion model of rat. However, little is known about the function and molecular mechanism of rno-miR-1298 in rat tumor cell. In this study, rno-miR-1298 was detected to be significantly down-regulated in rat tumor C6 cells. Moreover, overexpression of rno-miR-1298 obviously inhibited the proliferation and induced apoptosis in C6 cells. SET domain containing 7 (SETD 7) was identified to be a target of rno-miR-1298 using bioinformatics and luciferase reporter assays. Overexpression of rno-miR-1298 markedly reduced the expression of SETD 7 at protein level. Knockdown of SETD 7 also suppressed proliferation and promoted apoptosis in C6 cells. It was indicated that rno-miR-1298 affected cell proliferation and apoptosis of rat tumor cells by targeting SETD 7. Thus, the newly identified miR-1298/SETD 7 expands the elaboration of the mechanisms of the development and progression of tumors and may provide therapeutic target for tumors of nervous system.

Controlled stimuli-responsive release systems are a feasible and effective way to increase the efficiency of pesticides and help improve environmental pollution issues. However, near-infrared (NIR)-responsive systems for encapsulation of pesticides for controlling release have not been reported because of high cost and load ability of conventional NIR absorbers as well as complicated preparation process. Herein, we proposed polydopamine (PDA) microspheres as a photothermal agent owing to their abundant active sites, satisfactory photothermal efficiency, low cost, and easy fabrication, followed by capping with a PNIPAm thermosensitive polymer shell. In this core–shell PDA@PNIPAm hybrid system, the PDA core provided excellent temperature and NIR-light sensitivity as well as high loading capacity, while the PNIPAm applied as both a thermosensitive gatekeeper and a pesticide reservoir. The structure of the PDA@PNIPAm nanocomposites was characterized by transmission electron microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, dynamic light scattering, and thermogravimetric analysis; the results showed that the nanocomposites had a well-defined core–shell configuration for efficient loading of small pesticide molecules. Moreover, the core–shell PDA@PNIPAm nanocomposites exhibited high loading capacity and temperature- or NIR-controlled release performance. Overall, this system has significant potential in controlled drug release and agriculture-related fields as a delivery system for pesticides with photothermal responsive behavior.

In this letter, we will investigate the joint relay selection and subcarrier allocation problem for decode-and-forward relay assisted secure vehicle-to-vehicle (V2V) communications, where the eavesdroppers could be any illegal receivers or non-intending information destinations. The joint relay selection and subcarrier allocation scheme will be proposed to minimize the secure outage probability of each ${V_{\text {Tx}}}$ - ${V_{\text {Rx}}}$ pair while guaranteeing fairness. Specifically, the joint relay selection and subcarrier allocation problem in secure V2V communications is formulated into a random bipartite graph (RBG) model. The considered problem is then equivalent to generate the maximum matching on every sample of the RBG, thus it can be solved by R2HK algorithm with low complexity. By analyzing the properties of the RBG model-based maximum matching, the closed-form approximation formula of the secure outage probability is then obtained. Simulation results will not only verify the accuracy of theoretical derivations, but also show the performance improvement of the proposed approach.

Harmonic retrieval (HR) has a wide range of applications in the scenes where signals are modelled as a summation of sinusoids. Past works have developed a number of approaches to recover the original signals. Most of them rely on classical singular value decomposition, which are vulnerable to unexpected outliers. In this paper, to overcome this deficiency, we propose a new random-access HR model and develop robust algorithms combining L1-Tucker decomposition methods of Hankel tensor and novel frequency recovery techniques to solve such HR problem. Simulations are designed to compare our proposed methods with some existing tensor-based algorithms for HR. The numerical results demonstrate the outlier-insensitivity of our methods.

ABSTRACTIntroduction: Osteoactivin (OA) was first discovered in an osteopetrotic rat model using mRNA differential display a decade ago and has been studied recently. OA in bone tissue can directly or indirectly regulate the differentiation of osteoblasts by influencing cell behaviours, such as proliferation and adhesion, as well as inducing serial signal cascades, which would be of great importance in the field of tissue engineering. The results of recent studies have further demonstrated that OA plays a critical role in the differentiation and function of cells, especially in bone formation and fracture healing.Areas covered: The discovery, structure, and function of OA as well as its therapeutic potential in tissue regeneration of bone defects, kidney injury, liver damage, and muscle atrophy.Expert opinion: OA has great potential in promoting the regeneration of damaged tissues, particularly bone tissue, which is supported by a large body of data. Future studies should focus on exploring the underlying mechanism of OA as well as pursuing the ideal form of OA-related regenerative medicine.

The emergence of the D2D communications paradigm has transformed the way in which cellular networks are operated. Previous work in D2D communications, however, mainly focused on interference management and capacity maximization of both D2D links and cellular links. Recent literature has observed that the QoE can be greatly enhanced by caching contents in mobile devices, with a carefully designed caching strategy. In this article, we propose a novel hypergraph framework that designs the caching based D2D communication scheme by taking social ties among users and common interests into consideration. We first present the considered features of the D2D transmission scheme, social characteristics consideration, and interest similarity impact. The key concepts of hypergraph and related techniques, such as hypergraph coloring and multidimensional matching, are explained. Then some design issues with simulation results in the proposed framework are discussed in detail, which show the potential of the proposed approach. By jointly considering social ties, common interests, and the D2D transmission scheme, we believe the proposed framework explores new opportunities and future directions in caching based socially-aware D2D communications.

In gas turbine engines, the endwall misalignment (step geometries with various step heights) commonly exists between the combustor exit and the first nozzle guide vane endwall, due to assembly error, metal corrosion, and thermal expansion. The step geometries affect the secondary flow field near the endwall and coolant flow behavior, thereby leading to a significant variation in endwall film cooling, vane surface phantom cooling, and vane passage aerodynamic performances. This paper presents a detailed experimental and numerical study on endwall film cooling and vane pressure side surface phantom cooling at simulated gas turbine operating conditions (high inlet freestream turbulence level of 16%, exit Mach number of 0.85, and exit Reynolds number of 1.7 × 106). The experimental measurements were conducted at Virginia Tech’s transonic blowdown wind tunnel for two configurations: baseline cascade (HR = 0) and forward-facing step geometry (HR = −0.1). The numerical predictions were performed by solving the steady-state Reynolds-averaged Navier Stokes (RANS) with realizable k–ɛ turbulence model. Based on a double coolant temperature model, a novel numerical method for the predictions of adiabatic wall film cooling effectiveness was proposed. The qualitative and quantitative comparisons between the numerical prediction results and experimental data are provided in this paper. The results indicate that this method can reliably predict endwall film cooling distributions and vane pressure side surface phantom cooling distributions, and significantly reduce (more than 50%) numerical prediction errors. The effects of upstream step geometries were numerically studied at the design flow conditions (BR = 2.5, DR = 1.2), by quantizing the endwall film cooling effectiveness, endwall net heat flux reduction (NHFR), vane pressure side surface phantom cooling effectiveness, and total pressure loss coefficients (TPLC) for various upstream step heights: three forward-facing step heights (HR = −0.16, −0.1, and −0.06), a baseline cascade (HR = 0), and four backward-facing step heights (HR = 0.06, 0.1, 0.136, and 0.2). Results show the upstream forward-facing step geometry is beneficial for enhancing endwall film cooling (maximum enhancement level of 15%), endwall net heat flux reduction (maximum enhancement level of 10%), and vane pressure side surface phantom cooling (maximum enhancement level of 66.7%). Nevertheless, the upstream backward-facing step geometry is pernicious to the endwall film cooling, endwall heat flux reduction, and phantom cooling, and these pernicious effects have sharply deteriorated when the upstream step height is larger than a critical value (HR > 0.136). To be specific, the film cooling effectiveness (from 30% to 80%), net heat flux reduction (up to 78%), and phantom cooling effectiveness (completely disappeared) significantly decrease by introducing an overlarge backward-facing step height HR = 0.2. The upstream step geometries lead to deteriorated aerodynamic performance, though the reduction level may be slight (0.36% at HR = 0.136). These suggest that the overlarge backward-facing misalignment will increase the risk of thermal failure and must be avoided during the component assembly and the operational processes of a gas turbine.

With increasing aerodynamic and thermal loads, film cooling has been a popular technology integrated into the design of the modern gas turbine vane endwall, especially for the first-stage vane endwall. A staggering amount of research has been completed to quantify the effect of operating conditions and cooling hole geometrical properties. However, most of these investigations did not address the influence of the manufacturing tolerances, assembly errors, and operation degradations on the endwall misalignment. In this paper, uncertainty quantification (UQ) analysis was performed to quantify the impacts of upstream endwall misalignment uncertainties on the endwall film cooling performance and vane surface phantom cooling performance. The upstream endwall misalignment, step geometry with various step heights, commonly exists between the combustor exit and the first-stage vane endwall. Based on the non-intrusive polynomial chaos expansion (NIPC) and the uniform probability distribution assumption, the deviation (step height) uncertainties of the upstream endwall misalignment were quantified. To predict the endwall secondary flow and film cooling effectiveness in the transonic linear vane passage, the commercial computational fluid dynamic solver ANSYS FLUENT was used to numerically solve the three-dimensional steady-state Reynolds-Averaged Navier–Stokes (RANS) equations. The robustness analysis of endwall film cooling performance and phantom cooling performance to the upstream endwall misalignment was conducted for three design upstream step heights (ΔH): a baseline configuration (ΔH = 0 mm), two misaligned configurations with forward step (ΔH = −5 mm) and backward step (ΔH = 5 mm), respectively. Results show that the actual cooling performance has a high probability of deviating from the nominal value for the baseline configuration. The critical regions that are most sensitive to the upstream step misalignment are also identified by variances. The UQ results also show that the design geometry with a forward step has a more robust film cooling performance on endwall and phantom cooling performance on the vane pressure side surface, which means a smaller variance and a better expectation than the no-step configuration. In contrast, the design geometry with a backward step induces the reductions in the expectation of the film cooling effectiveness and coolant coverage and the amplification of performance fluctuations. This work provides a certain guiding direction for the optimization design for the upstream step geometry.

A miniaturized neutron spin flipper based on a high-TCsuperconductor film, developed at the China Spallation Neutron Source (CSNS), is presented. A neutron spin flipper is an essential component for performing polarized neutron experiments and, as such, constitutes a high priority for developing CSNS’s polarized neutron capability. To provide the beamlines with a universal neutron spin flipper operating over a wide wavelength band, the neutron spin flipper utilizes non-adiabatic spin flipping during transit through opposite magnetic fields that are mutually shielded by the superconductor Meissner effect. A compact vacuum heat shield and a low-power consumption sterling refrigerator maintained the superconducting condition while reducing the size and power input of the flipper. The prototype device was tested at the CSNS BL-20, which demonstrated a flipping efficiency of 99% at 4 Å.

In this paper, the endwall film cooling and vane pressure side surface phantom cooling performances of a first nozzle guide vane (NGV) with endwall contouring, similar to an industry gas turbine, were experimentally and numerically evaluated at the simulated realistic gas turbine operating conditions (high inlet freestream turbulence level of 16%, exit Mach number of 0.85, and exit Reynolds number of 1.7 × 106). A novel numerical method for the predictions of adiabatic wall film cooling effectiveness was proposed based on a double coolant temperature model. The credibility and accuracy of this numerical method were validated by comparing the predicted results with experimental data. Results indicate that the present numerical method can accurately predict endwall film cooling performance and vane surface phantom cooling performance for both the ideal low density ratio (DR = 1.2) and the typical high density ratio (DR = 2.0) conditions. The endwall film cooling effectiveness, vane surface phantom cooling effectiveness, and secondary flow field were compared and analyzed for the axisymmetric convergent contoured endwall at three coolant injection angles (small injection angle of θ = 40 deg, design injection angle of θ = 50 deg, large injection angle of θ = 60 deg), two density ratios (low density ratio of DR = 1.2 and typical high density ratio of DR = 2.0), and the design blowing ratio (M = 2.5), based on the commercial CFD solver ansys fluent. An analysis method of the coolant momentum flux φ (decomposed into the axial component φx and vertical component φz) was proposed to describe and explain the migration and mixing mechanisms of coolant flow. Results indicate that the proposed analysis method of the coolant momentum flux φ can accurately and reliably describe and explain the coolant flow physics, including the coolant lift-off, the interaction between the coolant and the mainstream, and the coolant migration in the vane passage. The increased coolant injection angles result in a deterioration of the endwall film cooling performance and vane pressure surface side phantom cooling performance. Nevertheless, the sensitivity of endwall film cooling effectiveness and phantom cooling effectiveness to coolant injection angles is variable, and is significantly affected by density ratio. This suggests that the coupling effects of the coolant injection angles and density ratio should be taken into account for the prediction of endwall film cooling and phantom cooling performances. It is very necessary for the optimized design of the coolant injection angles and the predictions of film cooling performance at the realistic density ratio.

Atheromatous plaque rupture and coronary artery stenosis/occlusion are leading causes of acute myocardial infarction (AMI). Other reasons for AMI are frequently overlooked. We report a rare case of AMI occurring after hypertrophic obstructive cardiomyopathy with paroxysmal atrial fibrillation. Although the patient showed multiple lead ST-T changes on an electrocardiogram and elevated circulating cardiac troponin I concentrations, no stenotic lesions were observed by repeated invasive coronary angiography examinations. Hypertrophic obstructive cardiomyopathy with paroxysmal atrial fibrillation was suspected as the primary cause of AMI. The patient received radiofrequency catheter ablation therapy and was free of atrial fibrillation and myocardial infarction 1 year postoperatively. The clinical management and outcome of the patient are also discussed.

A novel strategy for simultaneous removal of cyanide anions and copper cations was proposed. Firstly, TiO2@yeast hybrid microspheres with raspberry-like structure were fabricated by a facile hydrolysis method using titanium tetrachloride as Ti precursor. The physicochemical properties of the as-prepared samples were fully characterized. The bi-functional composites were then employed for the simultaneous removal of a typical mixture of cyanide and copper metal ions via bio-adsorption in dark and photo-catalysis under UV irradiation. The results showed that the satellitic TiO2nanoparticles within the TiO2@yeast raspberry-like structure functioned as the photocatalytic active sites providing the electron/hole pairs, while the yeast cores worked as the adsorbent to capture the cyanide and copper ions onto the photocatalytic active sites. The synergistic effects of the bio-adsorption by yeast and photo-catalysis by the TiO2nanoparticles over the bi-functional composites were demonstrated. Our results are expected to be of significant value for various environmental friendly applications.

A reasonable and effective control strategy for HEV (Hybrid Electric Vehicle) with HESS (Hybrid Energy Storage System) can improve the system efficiency and battery service life. A dynamic programming-based global optimal control strategy which fully considered the efficiency of each component in HEV is presented. To compare with the nonlinear proportion factor dynamic coordination strategy, the fuel consumption is not increased. The cycle numbers of battery are further decreased which benefits its cycle life improvement. The regenerative energy callback ratio improves 3% under the shanghai drive cycle as an example. Since this optimization algorithm considers efficiency of each subsystem, the efficiency optimum under the selected driving cycle was realized. It can also provide a reference for the non-linear scaling factor allocation strategies to determine the scale factors.