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Background: Community-acquired pneumonia (CAP) is a significant health issue among the elderly, with severe cases (SCAP) having high mortality rates. This study assesses the predictive significance of the stress hyperglycemia ratio (SHR) in elderly SCAP patients and its impact on outcomes in both diabetic and non-diabetic patients. Methods and materials: This retrospective study included 406 SCAP patients aged 65 or older from the Second People's Hospital of Lianyungang (January 2020 to December 2023). Data collected included demographics, medical history, vital signs, and lab results. SHR was calculated from initial blood glucose and estimated average glucose (HbA1c). Statistical analyses, including Cox regression and Kaplan-Meier analysis, evaluated SHR's impact on mortality. Mediation models explored the effects of neutrophil-lymphocyte ratio (NLR) and SHR. Results: The 28-day mortality rate was 21.67%. Deceased patients had higher age, Charlson Comorbidity Index, procalcitonin, NLR, glucose, and SHR levels compared to survivors (P < 0.05). Both SHR and NLR significantly increased mortality risk, particularly in non-diabetic patients. Combining NLR and SHR improved ROC AUC to 0.898, with 89.80% sensitivity and 81.10% specificity. Kaplan-Meier analysis showed higher cumulative survival for SHR < 1.14, regardless of diabetes status (P < 0.05). NLR mediated 13.02% of the SHR-survival relationship, while SHR mediated 14.06% of the NLR-survival relationship. Conclusion: Elevated SHR is a significant mortality risk factor in elderly SCAP patients, independent of diabetes status. Stringent glucose control and careful monitoring of SHR may improve outcomes in elderly patients with acute respiratory conditions. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to examine the influence of unintended facet arthrodesis on the therapeutic effectiveness of the dynamic neutralization system (Dynesys). Methods: This retrospective study enrolled consecutive patients who underwent posterior decompression and dynamic stabilization for lumbar spondylosis or spinal stenosis. Follow-up assessments included lumbar radiography, lumbar vertebral computerized tomography (CT), visual analog scale (VAS), and Oswestry disability index (ODI). Patients were classified into the facet fusion and non-fusion groups. The differences in the VAS scores for back pain and leg pain, ODI, intervertebral range of motion (ROM) at the surgical segments, and upper adjacent segments were assessed before and after treatment. Results: A total of 49 patients (29 males and 20 females) aged 31–65 years were enrolled and followed-up for over 40 months. Among the patients, 16 (32.7%) experienced unintended facet arthrodesis and were assigned to the fusion group, whereas the remaining patients were assigned to the non-fusion group. There was a significant increase in the incidence of facet arthrodesis in the surgical segments over time post-surgery (χ2 = 6.2, p < 0.05). The ROM of the surgical and upper adjacent segments, VAS scores for back pain and leg pain, and ODI were all significantly different before and after the operation (p < 0.05), but not between the fusion and non-fusion groups (p > 0.05). Conclusion: Although unintended facet arthrodesis is common after Dynesys procedure, the presence of facet arthrodesis does not significantly affect the efficacy of Dynesys in treating lumbar degenerative diseases. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, the application scope of LIDAR has been continuously expanding, especially in object detection. Yet existing LIDAR-based methods focus on detecting vehicles on regular roadways. Scenarios with a higher prevalence of pedestrians and cyclists, such as university campuses and leisure centers, have recently received limited attention. To solve this problem, in this paper we propose a novel detection algorithm named SecondRcnn, which is built upon the SECOND algorithm and introduces a novel two-stage detection method. In the first stage, it utilizes 3D sparse convolution on the voxel LIDAR points to learn feature representations. In the second stage, regression is employed to refine the detection bounding boxes generated by the Region Of Interest pooling network. The algorithm was evaluated on the widely used KITTI data set and demonstrated significant performance improvements in detecting pedestrians (4.61% improvement) and cyclist (6.5% improvement) compared to baseline networks. Our work highlights the potential for accurate object detection in scenarios characterized by a higher presence of pedestrians and cyclists. Advancing the use of LIDAR in the field of 3D detection. [ABSTRACT FROM AUTHOR]

Collagen membranes with high robustness and a defined stable biodegradation are of a great interest for dental surgery. Electrophoretic deposition (EPD) is a perspective candidate technology for their production, and in this article, the authors demonstrated the capabilities of its modification, a semipermeable barrier-assisted EPD (SBA-EPD). The SBA-EPD process was carried out at 60 V for 1,2, or 3 cycles 20 min each, after which the obtained membranes were crosslinked with 0.625% genipin. SBA-EPD allowed for the fabrication of membranes with high collagen packing density (0.0012 g/mm3) and high robustness, which depended on the number of SBA-EPD cycles. The highest Young's modulus, tensile strength, and strain at failure values of non-crosslinked samples corresponded to 3-cycle deposition (15.11 ± 1.78 MPa, 4.2 ± 1.6 MPa, 60 ± 12%, respectively). However, crosslinking diminished the statistical difference of these parameters among membranes of different deposition cycles (reaching for 3-cycle deposition 64 ± 5 MPa, 9.5 ± 1.1 MPa, 23.7 ± 2.0%, respectively). On day 21 after subcutaneous implantation, the non-crosslinked membranes showed a significant degree of resorption higher than that of crosslinked ones by 3.5 times in absolute values. As well, crosslinked membranes elicited a greater peri-implant pro-fibrotic and giant cell response. Overall, the mechanical characteristics of SBA-EPD membranes were mostly superior to commercially available products used for dental applications, while their biodegradation timeframes fitted the optimal window. The authors hope that their research will attract the attention to SBA-EPD as an emerging and perspective technology for the production of robust and defect-free collagen membranes for dental surgery. [ABSTRACT FROM AUTHOR]

Objectives: To construct effective prediction models for neoadjuvant radiotherapy (RT) and targeted therapy based on whole-tumor texture analysis of multisequence MRI for soft tissue sarcoma (STS) patients. Methods: Thirty patients with STS of the extremities or trunk from a prospective phase II trial were enrolled for this analysis. All patients underwent pre- and post-neoadjuvant RT MRI examinations from which whole-tumor texture features were extracted, including T1-weighted with fat saturation and contrast enhancement (T1FSGd), T2-weighted with fat saturation (T2FS), and diffusion-weighted imaging (DWI) sequences and their corresponding apparent diffusion coefficient (ADC) maps. According to the postoperative pathological results, the patients were divided into pathological complete response (pCR) and non-pCR (N-pCR) groups. pCR was defined as less than 5% of residual tumor cells by postoperative pathology. Delta features were defined as the percentage change in a texture feature from pre- to post-neoadjuvant RT MRI. After data reduction and feature selection, logistic regression was used to build prediction models. ROC analysis was performed to assess the diagnostic performance. Results: Five of 30 patients (16.7%) achieved pCR. The Delta_Model (AUC 0.92) had a better predictive ability than the Pre_Model (AUC 0.78) and Post_Model (AUC 0.76) and was better than AJCC staging (AUC 0.52) and RECIST 1.1 criteria (AUC 0.52). The Combined_Model (pre, post, and delta features) had the best predictive performance (AUC 0.95). Conclusion: Whole-tumor texture analysis of multisequence MRI can well predict pCR status after neoadjuvant RT and targeted therapy in STS patients, with better performance than RECIST 1.1 and AJCC staging. Key points: • MRI multisequence texture analysis could predict the efficacy of neoadjuvant RT and targeted therapy for STS patients. • Texture features showed incremental value beyond routine clinical factors. • The Combined_Model with features at multiple time points showed the best performance. [ABSTRACT FROM AUTHOR]

Vapor phase methylation of phenol with methanol is widely carried out to produce a variety of products such as anisole, cresols and xylenols due to their increasing application in industries. Numerous researches have been carried out to understand the mechanistic behavior of phenol methylation. Based on discussion of reaction mechanism, the present article covered methylation of phenol with methanol over various catalysts, including zeolites, metal oxides, spinel, phosphates, sulfates, hydrotalcites and others. Moreover, the influence of reaction conditions and catalyst deactivation behavior were described. Finally, this review paper gives useful insights for the future direction of phenol methylation with methanol. This review provides a summary for the process of phenol methylation with methanol: catalysts, reaction mechanism and deactivated behavior, etc. [ABSTRACT FROM AUTHOR]

Polarization is one of the inherent properties of light that human eyes cannot recognize. The polarized image collected by the optical system can be used for target detection, image enhancement, and dehazing. Nevertheless, a single image only represents certain polarization information on the targets. The fusion of images representing different polarization information is more beneficial to improve the image quality. Therefore, in this paper, we utilize a multiscale decomposition method to decompose the polarization degree image and intensity images into a base layer and detail layers. The local energy method is then used to fuse the base layer, and the nuclear norm is utilized to combine the detail layers. The fused base and detail layers are reconstructed to obtain the final fusion image. The proposed method is analyzed and compared to six state-of-the-art algorithms to exactly evaluate how effective it is. Experiments show that our method increases the contrast and clarity of the fusion image and has excellent details and texture. In addition, the outline of the fused image is clear, and the target is prominent, which is conducive to the target recognition. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to assess how solubility and dissolution profile comparisons under different pH conditions can be used to predict gastric pH-mediated drug-drug interaction (DDI) potential. We collected information for new molecular entities (NMEs) approved from 2003 to 2019 by the U.S. Food and Drug Administration (FDA) that had dedicated clinical DDI studies with acid-reducing agents (ARAs). Among these, 67 NMEs with solubility under different pHs and dissolution profiles generated in pH 1.2, 4.5, and 6.8 aqueous media were included for analysis. Similarity factor (f2) was used to compare dissolution profiles at different pHs for pH-mediated DDI prediction (e.g., f2<50 predicts positive DDI). Prediction accuracy was calculated based on the outcome comparison between predicted and observed DDIs. Based on dissolution profile comparisons and observed DDI data, weak base drugs (WBDs) (n = 49) showed 72.5% prediction accuracy under the fasted conditions, and 66.7% prediction accuracy under fed conditions. While using solubility and clinical dose for prediction, the prediction accuracy was 80% under fasted conditions and 66.7% under fed conditions, respectively. Comparison of dissolution profiles generated at pH 1.2, 4.5, and 6.8 can be used to predict gastric pH-mediated DDI potential for WBDs. It demonstrated comparable prediction accuracy under both fasted and fed conditions when compared to the prediction using solubility and clinical dose. Furthermore, dissolution profile comparison could add an additional understanding of possible impact of pH change on the release behavior of the drug product. [ABSTRACT FROM AUTHOR]

Software Defined Networking (SDN) architecture separates control plane and data plane, making network flexible and programmable. Since the large number of devices connected to the Internet of things (IoT) networks, the SDN-based network architecture makes the deployment and configuration of IoT much easier. In the IoT network, the fine-grained network traffic is critical to network management, then we propose a novel scheme to measure the fine-grained network traffic in the SDN-based IoT networks. In SDN-based IoT networks, the controller is very easy to be attacked, we introduce the blockchain technology into the measurement framework to ensure the security and consistency of the statistics. To measure flow traffic with low overhead and high accuracy, we collect the statistics of coarse-grained traffic of flows and fine-grained traffic of links, and model the network traffic as an ARIMA model and forecast the network traffic with the coarse-grained measurement of flows. Then, we propose an objective function to decrease the estimation errors. Due to the objective function is an NP-hard problem, we present a heuristic algorithm to obtain the optimal solution of the fine-grained measurement. Finally, we conduct some simulations to verify the validity of the proposed measurement scheme. Simulation results show that our approach is feasible and effective. [ABSTRACT FROM AUTHOR]

Enterprise Information System (EIS) is based on Internet of things (IoT) and aggregates a large amount of data of companies. Real-time reliable data transmission and data processing are very important for EIS. Network traffic of IoT is very important for network management and traffic planning in EIS. However, the measurement overheads and measurement accuracy are a contradiction for the fine-grained traffic measurement requirements. Artificial Intelligence (AI) has long promised to learn the natural feature of network traffic and make some actions about the prediction of traffic. In this paper, we propose an AI-based Lightweight Adaptive Measurement Method (ALAMM) for SDN to reduce the traffic measurement overheads and improve the measurement accuracy. Firstly, we use the AI to model and predict the flow traffic in the network. Based on the traffic prediction results, we propose an adaptive method to decide the traffic sampling frequency. Secondly, we send the measurement primitives to switches to measure the coarse-grained traffic of flows and links. Finally, the matrix filling and optimization method are proposed to recovery the fine-grained measurement and optimize the measurement result. Simulation results show that our approach can obtain network traffic with low overhead and high accuracy. [ABSTRACT FROM AUTHOR]

Author Correction: Hydrogen Sulfide Recruits Macrophage Migration by Integrin 1-Src-FAK/Pyk2-Rac Pathway in Myocardial Infarction Scale bars, 200 m and 500 m. Graph: Figure 4 The Src-FAK/Pyk2-Rac pathway responded to macrophage migration triggered by NaHS. (a) RAW264.7 cells were incubated for 1 h in the presence or absence of PF431396 (5 M), PF573228 (5 M), PP2 (10 M) or NSC23766 (25 M) respectively, followed by incubation with additional 100 M NaHS for 6 h. [Extracted from the article]

With the rapid increasing heat fluxes released from micro electronic devices, thermal management of electric components faces huge challenge. High working temperature generated by the chip will directly affect its performance. It is essential to develop advanced model to enhance heat transfer. In this study, a new microchannel heat sinks with impinging jets and dimples (MHSIJD) model with side outlets was proposed. Computational fluid dynamics simulation methodology with RNG k–ε turbulence model was used to investigate the performance of MHSIJD with side outlets. Valuation indices including thermal capability, pump consumption and overall performance were analyzed. Three models were compared with basic model (MHSIJD without side outlets): the cross section of the side outlet was set as 0.2 × 0.2 mm (Case 1), 0.4 × 0.4 mm (Case 2), and 0.6 × 0.6 mm (Case 3). The results showed that: (1) the MHSIJD with side outlets performs better heat transfer characteristic due to the alleviation of drift phenomenon. The heat transfer capacity can be increased by up to 17.51%; (2) the MHSIJD with side outlets exhibits a lower pressure drop, which can be reduced up to 22.39%; and (3) the overall performance of MHSIJD with side outlets is better due to its higher cooling efficiency and lower pump consumption. [ABSTRACT FROM AUTHOR]

Lipid-like nanoparticles (LNPs) have potential as non-viral delivery systems for mRNA therapies. However, repeated administrations of LNPs may lead to accumulation of delivery materials and associated toxicity. To address this challenge, we have developed biodegradable lipids which improve LNPs clearance and reduce toxicity. We modify the backbone structure of Dlin-MC3-DMA by introducing alkyne and ester groups into the lipid tails. We evaluate the performance of these lipids when co-formulated with other amine containing lipid-like materials. We demonstrate that these formulations synergistically facilitate robust mRNA delivery with improved tolerability after single and repeated administrations. We further identify albumin-associated macropinocytosis and endocytosis as an ApoE-independent LNP cellular uptake pathway in the liver. Separately, the inclusion of alkyne lipids significantly increases membrane fusion to enhance mRNA release, leading to synergistic improvement of mRNA delivery. We believe that the rational design of LNPs with multiple amine-lipids increases the material space for mRNA delivery. Lipid-like nanoparticles have applications as non-viral delivery systems for mRNA. Here, the authors develop biodegradable lipids with improved clearance and reduced toxicity. [ABSTRACT FROM AUTHOR]

Gaining precise control over the cellular entry pathway of nanomaterials is key in achieving cytosolic delivery, accessing subcellular environments, and regulating toxicity. However, this precise control requires a fundamental understanding of the behavior of nanomaterials at the bio-nano interface. Herein, we report a computational study investigating the synergistic effect of several key physicochemical properties of nanomaterials on their cellular entry pathways. By examining interactions between monolayer-protected nanoparticles and model cell membranes in a three-dimensional parameter space of size, surface charge/pKa, and ligand chemistry, we observed four different types of nanoparticle translocation for cellular entry which are: outer wrapping, free translocation, inner attach, and embedment. Nanoparticle size, surface charge/pKa, and ligand chemistry each play a unique role in determining the outcome of translocation. Specifically, membrane local curvature induced by nanoparticles upon contact is critical for initiating the translocation process. A generalized paradigm is proposed to describe the fundamental mechanisms underlying the bio-nano interface. Lin et al. investigate interactions between monolayer-protected nanoparticles and model cell membranes, and show four different types of nanoparticle translocation, i.e., outer wrapping, free translocation, inner attach, and embedment. The different translocation types greatly depend on synergism between nanoparticle size, surface charge, and ligand chemistry. [ABSTRACT FROM AUTHOR]

Tumor cells often reprogram their metabolism for rapid proliferation. The roles of long noncoding RNAs (lncRNAs) in metabolism remodeling and the underlying mechanisms remain elusive. Through screening, we found that the lncRNA Actin Gamma 1 Pseudogene (AGPG) is required for increased glycolysis activity and cell proliferation in esophageal squamous cell carcinoma (ESCC). Mechanistically, AGPG binds to and stabilizes 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3). By preventing APC/C-mediated ubiquitination, AGPG protects PFKFB3 from proteasomal degradation, leading to the accumulation of PFKFB3 in cancer cells, which subsequently activates glycolytic flux and promotes cell cycle progression. AGPG is also a transcriptional target of p53; loss or mutation of TP53 triggers the marked upregulation of AGPG. Notably, inhibiting AGPG dramatically impaired tumor growth in patient-derived xenograft (PDX) models. Clinically, AGPG is highly expressed in many cancers, and high AGPG expression levels are correlated with poor prognosis, suggesting that AGPG is a potential biomarker and cancer therapeutic target. PFKFB3 enhances glycolysis to promote cancer cell proliferation. Here, the authors identify a long noncoding RNA in esophageal squamous cell carcinoma, AGPG, which interacts with PFKFB3 and promotes its stability, leading to increased glycolysis and proliferation. [ABSTRACT FROM AUTHOR]

K0.5Na0.5NbO3 single crystal with trace amounts of lithium addition was grown by the seed-free solid-state crystal growth method. The Li addition is helpful for the growth of the crystals and improves the properties of the K0.5Na0.5NbO3 single crystals. A small amounts (0.2–0.3 at.%) of Li addition can trigger the formation of around 25% tetragonal phase. The occurrence of the phase transition may be due to the variety of the K/Na atomic ratio after Li substitution in both the Na and K sites. The optimum amount of Li addition in the crystal is 0.2–0.3 at.% in order to obtain a well performance K0.5Na0.5NbO3-based single crystal. The best electrical performance of these K0.5Na0.5NbO3-based crystals can be achieved as follows: d33 = 255 pC/N, tanδ = 1%, d*33 = 313 pm/V, and Pr = 26.1 μC/cm2, indicating that the structure and properties of K0.5Na0.5NbO3-based crystals grown by the seed-free solid-state crystal growth method can be closely affected by trace lithium carbonate addition. [ABSTRACT FROM AUTHOR]

Secret sharing is crucial to information security in wireless communications in the era of Internet of Things. In this paper, we study how to optimally share secrets between two and more users using the effect of wireless channel dynamics on the data link layer. For the two-user case, we formulate an optimization problem whose objective is to minimize the expectation of the probability that an eavesdropper receives all secret sharing packets. Our contributions are as follows: (i) we come up with the secret sharing mechanism that minimizes the aforementioned objective function and (ii) we perform analysis on our approach and derive the worst-case probability of the eavesdropper receiving all secret sharing packets. For the multi-user case, we focus on the scenario that three users within each other's communication range try to establish a common secret. A novel multi-user secret sharing mechanism that allows all three users to contribute toward the common secret is developed and analyzed. Our approach has two nice properties: (i) it is able to reset itself in case of packet transmission error and (ii) its secret sharing efficiency is high when the probability of packet transmission success is not low. Our results are validated via simulations. [ABSTRACT FROM AUTHOR]

Therapeutic messenger RNA vaccines enable delivery of whole antigens, which can be advantageous over peptide vaccines. However, optimal efficacy requires both intracellular delivery, to allow antigen translation, and appropriate immune activation. Here, we developed a combinatorial library of ionizable lipid-like materials to identify mRNA delivery vehicles that facilitate mRNA delivery in vivo and provide potent and specific immune activation. Using a three-dimensional multi-component reaction system, we synthesized and evaluated the vaccine potential of over 1,000 lipid formulations. The top candidate formulations induced a robust immune response, and were able to inhibit tumor growth and prolong survival in melanoma and human papillomavirus E7 in vivo tumor models. The top-performing lipids share a common structure: an unsaturated lipid tail, a dihydroimidazole linker and cyclic amine head groups. These formulations induce antigen-presenting cell maturation via the intracellular stimulator of interferon genes (STING) pathway, rather than through Toll-like receptors, and result in limited systemic cytokine expression and enhanced anti-tumor efficacy. Combinatorial development of heterocyclic lipidoids yields efficient mRNA vaccine vehicles that activate immune cells via the STING pathway. [ABSTRACT FROM AUTHOR]

Spreading a Ag nanowire (NW) dispersion using a bar coater onto a poly(ethylene terephthalate) (PET) film and evaporating the solvent yielded a transparent NW mesh. Further spreading a solution of bisphenol A diglycidyl ether and hardeners over this mesh using the bar coater and curing the epoxy precursors produced an epoxy-embedded NW mesh or an embedded NW electrode. Various techniques including scanning electron microscopy, transmission electron microscopy, and measurements of sheet resistance and transmittance were used to monitor the electrode fabrication process, which involved NW synthesis, casting NWs onto PET or glass substrates, subjecting the NW mesh to plasma treatment, and mesh embedment by an epoxy. Using our casting method, the areal density of the spread NWs and the thickness of the epoxy layer could be readily tuned by changing the concentrations of the NW dispersion and the epoxy precursory solution concentration, respectively. Our optimized electrodes had a Ag mass density of 1.0 × 10−5 g/cm2 in the NW mesh, embedded in an epoxy layer with a thickness of 0.6 µm. While many of the NW junctions in the mesh were locked in the coating matrix, sections of the NWs were arched over the epoxy layer to provide the required electrical contact with external devices. The optimized electrodes had a sheet resistance Rs value of 18.9 ± 4.8 Ω/□ and a transmittance (T%) of 86.5 ± 0.3% at 550 nm. In addition, the embedded electrode withstood 500 cycles of bending, 500 repetitions of rubbing, and over 100 cycles of an adhesion tape test without noticeable deteriorations in their Rs and T% values. Furthermore, their high-temperature stability and sulfurization resistance were significantly enhanced over those of the unembedded electrodes and they also withstood soaking in ethanol and acetone. The ready availability and affordability of the epoxy formulation and the high control of the epoxy deposition protocol suggest that this electrode fabrication strategy has significant practical value. [ABSTRACT FROM AUTHOR]

A novel Pt entrapped in Bi2O3 decorated TiO2 nanotube (Pt-in/Bi2O3@TNT) composite was obtained by the assistance of vacuum impregnation and subsequent calcination. Attributed to the confinement effect, TiO2 nanotube (TNT) confined Pt nanoparticles catalyst (Pt-in/TNT) processed better ethylene (C2H4) combustion activity than Pt nanoparticles loaded on TNT catalyst (Pt-out/TNT). More distinctly, the Pt-in/Bi2O3@TNT displayed enhanced activity towards C2H4 combustion, a nearly complete depletion at 150 °C was achieved, which is 30 °C lower than that of the Pt-in/TNT. The characterizations of X-ray photoelectron spectroscopy (XPS) not only verified that the electron density destitution of Pt in Pt-in/Bi2O3@TNT is significantly enhanced due to the modulation of layered Bi2O3 on the confinement effect of TNT, but also indicated that the catalyst facilitates the forming and migrating of active oxygen species. This work presents an efficient confinement effect combined with electron modifier strategy to construct high-performance catalysts for environmental applications. [ABSTRACT FROM AUTHOR]

This paper studies an optimal ON-OFF control problem for a class of discrete event systems with real-time constraints. Our goal is to minimize the overall costs, including the operating cost and the wake-up cost, while still guaranteeing the deadline of each individual task. In particular, we consider the homogeneous case in which it takes the same amount of time to serve each task and each task needs to be served by d seconds upon arrival. The problem involves two subproblems: (i) finding the best time to wake up the system and (ii) finding the best time to let the system go to sleep. We study the two subproblems in both off-line and on-line settings. In the off-line case that all task information is known a priori, we combine sample path analysis and dynamic programming to come up with the optimal solution. In the on-line scenario where future task information is completely unknown, we show that the optimal time to wake up the system can be obtained without relying on future task arrivals. We also perform competitive analysis for on-line control and derive the competitive ratios for both deterministic and random controllers. [ABSTRACT FROM AUTHOR]

We study a class of prioritized Discrete Event Systems (DESs) that involve the control of resources allocated to tasks under real-time constraints. Our work is motivated by applications in communication systems, computing systems, and manufacturing systems where the objective is to minimize energy consumption while guaranteeing that task deadlines are always met. In the off-line setting, we discover several structural properties of the optimal sample path of such DESs. Using the structural properties, we also propose a greedy algorithm which is shown numerically near optimal. For on-line control, we design a Receding Horizon (RH) controller. Using worst-case estimation, the RH control is able to guarantee feasibility (when the off-line problem is feasible) and achieve good performance. [ABSTRACT FROM AUTHOR]

With excellent high-temperature stability (up to 1000 K) and favorable electrical properties for thermoelectric application, TiNiSn-based half-Heusler (HH) alloys are expected to be promising thermoelectric materials for the recovery of waste heat in the temperature ranging from 700 K to 900 K. However, their thermal conductivity is always relatively high (5-10 W/mK), making it difficult to further enhance their thermoelectric figure-of-merit (ZT). In the past decade, introducing nano-scale secondary phases into the HH alloy matrix has been proven to be feasible for optimizing the thermoelectric performance of TiNiSn. In this study, a series of TiNiSn-based alloys have been successfully synthesized by a simple solid-state reaction. The content and composition of the heterogeneous phase (TiNi2Sn and Sn) is accurately regulated and, as a result, the thermal conductivity successfully reduced from 4.9 W m−1 K−1 to 3.0 Wm−1 K−1 (750 K) due to multi-scale phonon scattering. Consequently, a ZT value of 0.49 is achieved at 750 K in our TiNiSn-based thermoelectric materials. Furthermore, the thermal stability of TiNiSn alloys is enhanced through reducing the Sn substance phase. [ABSTRACT FROM AUTHOR]

A novel microwave dielectric ceramics Bi(ScMo)O with low firing temperature were prepared via the solid reaction method. The specimens have been characterized using scanning electron microscopy, X-ray diffraction, Raman spectroscopy and DC conductivity. The Bi(ScMo)O ceramics showed B-site ordered Scheelite-type structure with space group C2/c. Raman analysis indicated that prominent bands were attributed to the normal modes of vibration of MoO tetrahedra. The dielectric loss of Bi(ScMo)O ceramics can be depended strongly the bulk conductivity by DC measurement. The superior microwave dielectric properties are achieved in the Bi(ScMo)O ceramic sintered at 875 °C/4 h, with dielectric constant ~ 25, Q × f ~ 51,716 GHz at 6.4522 GHz and temperature coefficient of resonance frequency ~ − 70.4 ppm/°C. It is a promising microwave dielectric material for low-temperature co-fired ceramics technology. [ABSTRACT FROM AUTHOR]

With a high flexibility and an adjustable electronic structure, reduced graphene oxide (RGO) is a potential candidate for flexible thermoelectric materials. Here, we report that flexible RGO/tellurium nanowires (Te NWs)/RGO sandwich structure hybrid films are prepared on glass fabrics through the drop-cast method. The addition of 20 wt.% Te NWs into a RGO matrix remarkably improves the Seebeck coefficient from 15.2 μV/K to 89.7 μV/K while maintaining relatively high electrical conductivity, thus resulting in a one order of magnitude higher power factor value compared with the Te NWs. According to the values of carrier mobility and concentration of hybrid films, the improved thermoelectric properties are presented because of the energy filtering effect on the interfaces in hybrid films. This article suggests that RGO/Te NWs/RGO hybrid films would be promising for fabricating flexible energy sources. [ABSTRACT FROM AUTHOR]

Anomalous or unnormal multimedia medical devices are to yield anomaly network traffic and affect the diagnosis about medical issues. How to find anomaly network traffic is significantly important for normal applications of multimedia medical devices. This paper studies traffic anomaly detection problem in large-scale communication networks with multimedia medical devices. We employ empirical mode decomposition method and wavelet packet transform to propose an accurate detection method to capture it. Firstly, we use the wavelet packet transform to pre-treat network traffic. Network traffic is decomposed into multiple narrowband signals exhibiting more detailed features of network traffic. Secondly, the empirical mode decomposition method is utilized to divide these narrowband signals into the intrinsic mode function at different scales, in time and time-frequency domains. We calculate the spectral kurtosis value of the intrinsic mode function at these different scales to remove false components of the empirical mode decomposition. As a result, we can obtain new time and time-frequency signals which highlight the hidden nature of anomaly network traffic. Thirdly, we perform the reconstruction of empirical mode decompositions and wavelet packet transforms for the above time and time-frequency signals to attain a series of new time signals. Then we can find and diagnose abnormal network traffic. Simulation results show that our method is effective and promising. [ABSTRACT FROM AUTHOR]

A dispersive solid-phase extraction (DSPE) method of mixing two different materials (C and MAX) was developed as extraction procedure, which provided better extraction yields (>82.1 %) for all analytes and more appropriate sample purification from endogenous interference materials compared with common SPE. Analyte separation was achieved on a C reversed phase column at the wavelength of 265 nm by high performance liquid chromatography (HPLC). The method was validated in terms of extraction yield, precision and accuracy. These assays gave mean accuracy values higher than 89 % with RSD values which were always less than 4.1 %. The method has a more simple operation process and achieves higher accuracy and precision than SPE. It has been successfully applied to plasma samples from rats after oral administration of target compounds. [ABSTRACT FROM AUTHOR]

With high carrier mobility and low cost, reduced graphene oxide (RGO) shows bright prospects for use in the field of thermoelectric materials. To investigate the intrinsic thermoelectric properties of RGO sheets, we prepared RGO papers which were reduced by HBr solution for 5 min, 20 min, and 60 min, respectively. Thermogravimetry analysis (TGA) and Raman analysis showed that the conjugated carbon network of graphene oxide (GO) was restored during the reduction process and the thermal stability of the RGO papers was much better than that of GO paper. The RGO paper that was reduced for 60 min and then annealed in Ar/H atmosphere exhibited the highest electrical conductivity of 3.22 × 10 S/m at 160°C. As the reduction degree of the RGO paper deepens, the Seebeck coefficient gradually transforms from positive to negative, indicating that the conduction type of RGO paper can be controlled by regulating the reduction degree. [ABSTRACT FROM AUTHOR]

By using the parent monomers, 3,4-ethylenedioxythiophene and aniline, a series of nanocomposites consisting of different mass ratios of polyaniline (PANI) to poly(3,4-ethylenedioxythiophene) (PEDOT) have been successfully prepared in hydrochloric acid solution through oxidative polymerization, then redoped with p-toluenesulfonic acid ( p-TSA). Firstly, PEDOT nanoparticles were fabricated via chemical oxidation polymerization in reverse (water-in-oil) microemulsions. Then, PANI-doped PEDOT nanoparticles were formed by oxidative polymerization of aniline to form PANI/PEDOT nanofibers. The resulting nanostructured components were characterized by scanning electron microscopy (SEM) and a series of spectroscopic methods. The presence of PEDOT increased the room-temperature electrical conductivity of the PANI/PEDOT nanocomposites by more than two orders of magnitude in comparison with the parent PANI. Moreover, the PANI/PEDOT nanocomposites showed better thermoelectric properties than PANI. Different concentrations of p-TSA also affected the electrical conductivity and Seebeck coefficient of the nanocomposites. With increasing temperature, both the electrical conductivity and Seebeck coefficient increased. [ABSTRACT FROM AUTHOR]

Nanostructured thermoelectric (TE) materials, for example SbTe, PbTe, and SiGe-based semiconductors, have excellent thermoelectric transport properties and are promising candidates for next-generation TE commercial application. However, it is a challenge to synthesize the corresponding pure nanocrystals with controlled size by low-temperature wet-chemical reaction. Herein, we report an alternative versatile solution-based method for synthesis of plate-like SbTe nanoparticles in a flask using SbCl and Te powders as raw materials, EDTA-Na as complexing agent, and NaBH as reducing agent in the solvent (distilled water). To investigate their thermoelectric transport properties, the obtained powders were cold compacted into cuboid prisms then annealed under a protective N atmosphere. The results showed that both the electrical conductivity ( σ) and the power factor ( S σ) can be enhanced by improving the purity of the products and by increasing the annealing temperature. The highest power factor was 2.04 μW cm K at 140°C and electrical conductivity remained in the range 5-10 × 10 S m. This work provides a simple and economic approach to preparation of large quantities of nanostructured SbTe with excellent TE performance, making it a fascinating candidate for commercialization of cooling devices. [ABSTRACT FROM AUTHOR]

Titania embedded with layer-cracking nanostructures (sodium titanate) was synthesized by a hydrothermal method and a subsequent sintering process. The structure and morphology were determined by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N adsorption-desorption experiments. In thermoelectric investigations, this nanocomposite has reduced thermal conductivity, where the minimum reaches about 2.4 W/m K at 700°C. This value is relatively low among the transition-metal oxides. Strong boundary scattering at the interfaces of the layered nanostructures and point defect scattering resulting from volatilization of Na ions seem to be main reasons for the suppression of phonon heat transfer. On the other hand, the power factor shows no apparent deterioration. Our results suggest that introduction of proper layer-cracking nanostructures into thermoelectric hosts might be effective to enhance their performance. [ABSTRACT FROM AUTHOR]

Modified micro-emulsion polymerization was successfully used to synthesize a kind of ambient temperature self-crosslinking core-shell emulsion, consisting of polyacrylate core and vinyltriethoxysilane (VTES) modified polyacrylate shell, by varying the ratio of soft monomer (BA) and hard monomer (MMA) which is different in the core and shell. The emulsion and its film formed at ambient temperature were characterized by attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Core-shell structure was clearly shown in TEM micrographs, and two distinct glass transition temperatures ( T) were confirmed by DSC analysis. Lower T of core phase analyzed by DSC and self-crosslinking properties of VTES characterized by crosslinking degree cause latex particles form continuous film at ambient temperature. Thermal and mechanical properties and the surface properties of the latex films were also investigated. Results showed that the core-shell latex films containing 5 and 7.5 % VTES exhibited higher thermal stability, better mechanical properties, higher contact angle, and water resistance compared with pure polyacrylate film. [ABSTRACT FROM AUTHOR]

The hysteresis characteristic is the major deficiency in the positioning control of magnetic shape memory alloy actuator. A Prandtl-Ishlinskii model was developed to characterize the hysteresis of magnetic shape memory alloy actuator. Based on the proposed Prandtl-Ishlinskii model, the inverse Prandtl-Ishlinskii model was established as a feedforward controller to compensate the hysteresis of the magnetic shape memory alloy actuator. For further improving of the positioning precision of the magnetic shape memory alloy actuator, a hybrid control method with hysteresis nonlinear model in feedforward loop was proposed. The control method is separated into two parts: a feedforward loop with inverse Prandtl-Ishlinskii model and a feedback loop with neural network controller. To validate the validity of the proposed control method, a series of simulations and experiments were researched. The simulation and experimental results demonstrate that the maximum error rate of open loop controller based on inverse PI model is 1.72%, the maximum error rate of the hybrid controller based on inverse PI model is 1.37%. [ABSTRACT FROM AUTHOR]

In this paper, we report on the obtention of highly ordered VO nanotube arrays synthesized by the simple sol-gel template method. Techniques of transmission electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy were used to characterize the morphology and structure of the as-synthesized nanotube arrays. It is found that the size of the as-obtained nanotubes has the dimension of 180-220 nm in outer diameter, 110-140 nm in inner diameter and up to 10 μm in length. The results show that as-synthesized sample is assigned to VO (B) phase in expected V/O ratio with V existing in the +4 oxidation state. [ABSTRACT FROM AUTHOR]

The monolayer AlO:Ag thin films were prepared by magnetron sputtering. The microstructure and optical properties of thin film after annealing at 700 °C in air were characterized by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and spectrophotometer. It revealed that the particle shape, size, and distribution across the film were greatly changed before and after annealing. The surface plasmon resonance absorption and thermal stability of the film were found to be strongly dependent on the film thickness, which was believed to be associated with the evolution process of particle diffusion, agglomeration, and evaporation during annealing at high temperature. When the film thickness was smaller than 90 nm, the film SPR absorption can be attenuated until extinct with increasing annealing time due to the evaporation of Ag particles. While the film thickness was larger than 120 nm, the absorption can keep constant even after annealing for 64 h due to the agglomeration of Ag particles. On the base of film thickness results, the multilayer AlO:Ag solar selective thin films were prepared and the thermal stability test illustrated that the solar selectivity of multilayer films with absorbing layer thickness larger than 120 nm did not degrade after annealing at 500 °C for 70 h in air. It can be concluded that film thickness is an important factor to control the thermal stability of AlO:Ag thin films as high-temperature solar selective absorbers. [ABSTRACT FROM AUTHOR]

Electrochimcal behaviors of rusticyanin (Rus.) isolated from Acidithiobacillus ferrooxidans were investigated through Rus.-ZnS-QDs/L-Cys/Au electrode. The cyclic voltammetric results indicate that rusticyanin immobilized on the surface of Rus.-ZnS-QDs/L-Cys/Au electrode can undergo a direct quasi-reversible electrochemical reaction. The immobilized rusticyanin is not denatured and still retains its activity in the temperature range of 19-43 °C. The reduction ability of the protein increases and its oxidation ability becomes weak with the increase of pH from 6.0 to 7.8. Fe ions in the solution can promote the electron transfer kinetics of the immobilized rusticyanin and make its peak potentials ( φ) markedly move negatively. [ABSTRACT FROM AUTHOR]

The AFM image will be distorted due to the tip-broadening effect. It may be mathematically represented as the effect of the tip's convolution on the real image. As a result, the true geometry of the sample surface can not be obtained. If the tip shape could be known accurately, such distortion can be eliminated with the adoption of disconvolution operation. It is of practical significance in the accurate reconstruction of the AFM image. Among the current tip modeling algorithms, the blind tip estimation algorithm based on mathematical morphology is widely applied. However, it takes much time and has difficulties in defining the optimal noise threshold. In view of the above problems, this paper proposes a new blind tip evaluation method to accelerate the speed of blind tip modeling calculation and realize the accurate reconstruction of the AFM image. The simulation and the experimental results demonstrate the feasibility and effectiveness of the above research method. [ABSTRACT FROM AUTHOR]

A new type of piezoelectric electro-hydraulic servo valve system was proposed. And then multilayer piezoelectric actuator based on new piezoelectric ceramic material was used as the electricity-machine converter of the proposed piezoelectric electro-hydraulic servo valve. The proposed piezoelectric electro-hydraulic servo valve has ascendant performance compared with conventional ones. But the system is of high nonlinearity and uncertainty, it cannot achieve favorable control performance by conventional control method. To develop an efficient way to control piezoelectric electro-hydraulic servo valve system, a high-precise fuzzy control method with hysteresis nonlinear model in feedforward loop was proposed. The control method is separated into two parts: a feedforward loop with Preisach hysteresis nonlinear model and a feedback loop with high-precise fuzzy control. Experimental results show that the hysteresis loop and the maximum output hysteresis by the PID control method are 4.22% and 2.11 μm, respectively; the hysteresis loop and the maximum output hysteresis by the proposed control method respectively are 0.74% and 0.37 μm, respectively; the maximum tracking error by the PID control method for sine wave reference signal is about 5.02%, the maximum tracking error by the proposed control method for sine wave reference signal is about 0.85%. [ABSTRACT FROM AUTHOR]

Human beings have had a tremendous impact on natural ecosystems and are now the principal power to change the biosphere. It is logical that we should pay close attention to the interaction between human systems and environmental systems. Taking Minqin basin, Gansu Province, as a case, this paper focuses on the evolution of regional physical environments and the cultural systems by which people maintain their relationships with those environments. This paper presents the conceptual framework for the man-land system. Expecting to accelerate the regional sustainable development, it also analyses the evolutionary mechanism of regional man-land system. On the basis of reviewing and analyzing the evolution of man-land system in Minqin basin, the paper also brings forward an adjusting mode for the studied area, which consists of three aspects: to build up a concept that economic growth must harmonize with environmental quality’s and land productivity’s improvement; to make a whole planning and management in the drainage area; and to push forward the technique of water-saving irrigation and establish water-saving agricultural system. It’s meaningful for resource exploitation and sustainable development of Chinese northwestern arid area, which is represented by Minqin basin, by understanding what great changes the basin has experienced and is experiencing at the global background, and studying its time order and territorial structure, the system’s character and law of evolution, trend and the regulating ways to improve man-land relationship. [ABSTRACT FROM AUTHOR]

Bioequivalence (BE) studies support the approval and clinical use of both new drug and generic drug products. Virtual BE studies have been conducted using physiologically based pharmacokinetic absorption models (PBPK AMs) to aid the evaluations of generic drug products. The aim of the current study is to determine the dissolution boundary for maintaining BE between the test and reference oseltamivir phosphate (OP) drug products using the PBPK AM–based virtual BE studies in adults and pediatrics. The adult PBPK AM for OP and its metabolite oseltamivir carboxylate (OC) are developed and verified/validated using intravenous and oral data from multiple generic OP products. The pediatric PBPK AM is extrapolated from the adult PBPK AM. The virtual BE analysis is conducted using simulated PK profiles from the reference products and the generic products with theoretical dissolution profiles as inputs. Results indicate that the generic products with 10% slower dissolution profile than the pivotal reference bio-batch could still maintain BE to the reference in adults. In contrast, a stringent trend of dissolution boundary is observed for pediatrics (6% slower for adolescents, 4% slower for 0–2-month neonates) to maintain BE. This study addresses the important applications of PBPK AM in evaluating BE in different age populations, mitigating risk of formulation/batch changes, and providing a quantitative basis for setting clinically relevant dissolution specifications for OP and OC in both adults and pediatrics. [ABSTRACT FROM AUTHOR]