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Exploring the transport characteristics of leakage gas in the condenser can facilitate quicker identification of leak points when using Helium tracer gas method for detection. We construct a 3-D physical model of the condenser to simulate the Helium gas leakage process within the tube bundle. On the steam side, we adopt RNG k-e, porous media, steam condensation, and convective diffusion models to describe steam and leakage gas-flow. On the waterside, we use the tube bundle thermal resistance model to describe the steam-water heat transfer. The research concludes with three key points. When the centripetal pressure gradient is insufficient, there will be leakage gas enrichment, resulting in flowing out in the form of diffusion. When there is no centripetal pressure gradient in the tube bundle region, it will extract only a small amount of upstream leakage gas along with steam through the flow. When reaching a stable level for leakage gas, the leakage intensity is proportional to the outlets' flow rate but is independent of the transport form. The deviation of the mass-flow rate decreases with the mesh quantity increasing, which is less than 2% when the mesh quantity is over 638228. The deviation between simulated and actual values of the two parameters is less than 5%, which reveals the good agreement between numerical calculation and actual work conditions. These conclusions can assist employees and researchers in evaluating data on leak points and enhancing detection techniques. [ABSTRACT FROM AUTHOR]

Accurately predicting the production rate and estimated ultimate recovery (EUR) of shale oil wells is vital for efficient shale oil development. Although numerical simulations provide accurate predictions, their high time, data, and labor demands call for a swifter, yet precise, method. This study introduces the DuongeCNNeLSTM (D-C-L) model, which integrates a convolutional neural network (CNN) with a long short-term memory (LSTM) network and is grounded on the empirical Duong model for physical constraints. Compared to traditional approaches, the D-C-L model demonstrates superior precision, efficiency, and cost-effectiveness in predicting shale oil production. [ABSTRACT FROM AUTHOR]

BACKGROUND: To evaluate whether a simplified self-instruction card can help potential rescue providers use automated external defibrillators (AEDs) more accurately and quickly. METHODS: From June 1, 2018, to November 30, 2019, a prospective longitudinal randomized controlled simulation study was conducted among 165 laypeople (18--65 years old) without prior AED training. A self-instruction card was designed to illuminate key AED operation procedures. Subjects were randomly divided into the card (n=83) and control (n=82) groups with age stratification. They were then individually evaluated in the same simulated scenario to use AED with (card group) or without the self-instruction card (control group) at baseline, post- training, and at the 3-month follow-up. RESULTS: At baseline, the card group reached a significantly higher proportion of successful defibrillation (31.1% vs. 15.9%, P=0.03), fully baring the chest (88.9% vs. 63.4%, P<0.001), correct electrode placement (32.5% vs. 17.1%, P=0.03), and resuming cardiopulmonary resuscitation (CPR) (72.3% vs. 9.8%, P<0.001). At post-training and follow-up, there were no significant differences in key behaviors, except for resuming CPR. Time to shock and time to resume CPR were shorter in the card group, while time to power-on AED was not different in each phase of tests. In the 55-65 years group, the card group achieved more skill improvements over the control group compared to the other age groups. CONCLUSION: The self-instruction card could serve as a direction for first-time AED users and as a reminder for trained subjects. This could be a practical, cost-effective way to improve the AED skills of potential rescue providers among different age groups, including seniors. [ABSTRACT FROM AUTHOR]

In the wake of the COVID-19 outbreak, China implemented emergency epidemic prevention and control measures, which played a positive role in economic and social development as well as the containment of the epidemic. Based on stock trading data from February 2020 to December 2022, this paper examines the impact of these measures on the stock returns of A-share listed companies. The findings of the study indicate that social distancing and health measures generally increase stock market returns, despite the varying magnitude of their effects. In addition, the analysis of two aspects, namely the listed sectors and the industry response analysis, further corroborates the main conclusion that social distancing policies have a more pronounced effect on the stock market. The study helps investors understand how the stock market responds to government announcements and enables policymakers to further explore the impact of policy responses during major public health events and their influence on economic and social welfare. [ABSTRACT FROM AUTHOR]

As the second most abundant natural polymer, accounting for approximately 30% of the organic carbon in the biosphere, lignin plays an essential role in plant development. However, a high lignin content affects the nutritional quality of alfalfa (Medicago sativa L.), the most widely cultivated perennial legume forage crop. Histological analysis indicated that G-lignin and S-lignin were present in the stem, leaf, and petiole of alfalfa, and the deposition of lignin increased gradually in descending internodes. Neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) contents continually increased from the top to the bottom of the stem, and ADL content showed a similar trend in leaves. Alfalfa leaves and stems from five different nodes (1, 2, 4, 6, and 8) were used as materials to investigate molecular regulatory mechanisms in lignin synthesis by RNA sequencing. Respectively 8074 and 7752 differentially expressed genes (DEGs) were identified in leaves and stems, and 1694 DEGs were common to the two tissues. "Phenylpropanoid biosynthesis" was the most enriched pathway in both leaves and stems, and 134 key regulatory genes in lignin synthesis were identified by a weighted gene co-expression network analysis. The NAC family transcription factor MsNST1 gene was highly expressed in old leaf and stem tissues. The deposition pattern of G- and S-lignin differed among M. truncatula wild-type, nst1 mutants, and overexpression lines, and the transcription levels of lignin synthesis genes such as HCT, F5H, and COMT in these three materials also differed. These results suggest that MsNST1 affects lignin synthesis in alfalfa. These findings provide a genetic basis and abundant gene resources for further study of the molecular mechanisms of lignin synthesis, laying a foundation for low-lignin alfalfa breeding research. [ABSTRACT FROM AUTHOR]

The paper develops a two-type behavioral heterogeneous agent model including fundamentalists and chartists. It examines whether investors' behavioral heterogeneity is related to the excessive volatility of RMB exchange rate. We use the deviation of the real exchange rate from the fundamental exchange rate as a measure of excessive exchange rate volatility. The fundamental value is calculated by the revised RMB fundamental exchange rate model with cointegration technology. After estimating the behavioral heterogeneous agent model using the monthly RMB exchange rate data from October 2006 to November 2020, we find that the heterogeneity of traders in price and trading strategies can significantly explain excess volatility of the RMB exchange rate. Our analysis of two significant fluctuations in 2015-2016 and 2018-2019 further corroborates our key finding that investors' behavioral heterogeneity plays an important role in explaining excess volatility of RMB exchange rate. [ABSTRACT FROM AUTHOR]

The accelerated proximal methods (APM) have become one of the most important optimization tools for large-scale convex composite minimization problems, due to their wide range of applications and the optimal convergence rate in first-order algorithms. However, most existing theoretical results of APM are obtained by assuming that the gradient oracle is exact and the proximal mapping must be exactly solved, which may not hold in practice. This work presents a theoretical study of APM by allowing to use inexact gradient oracle and approximate proximal mapping. Specifically, we analyze inexact APM by improving the approximate duality gap technique (ADGT) which was originally designed for convergence analysis for first-order methods with both exact gradient oracle and proximal mapping. Our approach has several advantages: 1) we provide a unified convergence analysis that allows both inexact gradient oracle and approximate proximal mapping; 2) our proof is generic that naturally recovers the convergence rates of both accelerated and non-accelerated proximal methods, on top of which the advantages and the disadvantages of acceleration can be easily derived; 3) we derive the same convergence bound as previous methods in terms of inexact gradient oracle, but a tighter convergence bound in terms of approximate proximal mapping. [ABSTRACT FROM AUTHOR]

Heavy monsoon rainfall ravaged a large swath of East Asia in summer 2020. Severe flooding of the Yangtze River displaced millions of residents in the midst of a historic public health crisis. This extreme rainy season was not anticipated from El Niño conditions. Using observations and model experiments, we show that the record strong Indian Ocean Dipole event in 2019 is an important contributor to the extreme Yangtze flooding of 2020. This Indian Ocean mode and a weak El Niño in the Pacific excite downwelling oceanic Rossby waves that propagate slowly westward south of the equator. At a mooring in the Southwest Indian Ocean, the thermocline deepens by a record 70 m in late 2019. The deepened thermocline helps sustain the Indian Ocean warming through the 2020 summer. The Indian Ocean warming forces an anomalous anticyclone in the lower troposphere over the Indo-Northwest Pacific region and intensifies the upper-level westerly jet over East Asia, leading to heavy summer rainfall in the Yangtze Basin. These coupled ocean-atmosphere processes beyond the equatorial Pacific provide predictability. Indeed, dynamic models initialized with observed ocean state predicted the heavy summer rainfall in the Yangtze Basin as early as April 2020. [ABSTRACT FROM AUTHOR]

Abstract: Chronic neuropathic pain is frequently accompanied by memory impairment, yet the underlying mechanisms remain unclear. Here, we showed that mice displayed memory impairment starting at 14 days and lasting for at least 21 days after chronic constriction injury (CCI) of unilateral sciatic nerve in mice. Systemic administration of the pan histone deacetylase (HDAC) inhibitor sodium butyrate attenuated this memory impairment. More specifically, we found that hippocampus HDAC3 was involved in this process because the levels of its mRNA and protein increased significantly in the hippocampus at 14 and 21 days after CCI, but not sham surgery. Systemic administration of the selective HDAC3 antagonist RGFP966 attenuated CCI-induced memory impairment, improved hippocampal long-term potentiation impairment, and rescued reductions of dendritic spine density and synaptic plasticity-associated protein in the hippocampus. In addition, HDAC3 overexpression in the hippocampus led to memory impairment without affecting basal nociceptive responses in naive mice. Our findings suggest that HDAC3 contributes to memory impairment after CCI by impairing synaptic plasticity in hippocampus. Histone deacetylase 3 might serve as a potential molecular target for therapeutic treatment of memory impairment under neuropathic pain conditions. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective analysis.Objective: Our goal was to provide a predictive model and a risk classification system that predicts cancer-specific survival (CSS) from spinal and pelvic tumors.Summary Of Background Data: Primary bone tumors of the spinal and pelvic are rare, thus limiting the understanding of the manifestations and survival from these tumors. Nomograms are the graphical representation of mathematical relationships or laws that accurately predict individual survival.Methods: A total of 1033 patients with spinal and pelvic bone tumors between 2004 and 2016 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. Multivariate Cox analysis was used on the training set to select significant predictors to build a nomogram that predicted 3- and 5-year CSS. We validate the precision of the nomogram by discrimination and calibration, and the clinical value of nomogram was assessed by making use of a decision curve analyses (DCA).Results: Data from 1033 patients with initially-diagnosed spinal and pelvic tumors were extracted from the SEER database. Multivariate analysis of the training cohort, predictors included in the nomogram were age, pathological type, tumor stage, and surgery. The value of C-index was 0.711 and 0.743 for the internal and external validation sets, respectively, indicating good agreement with actual CSS. The internal and external calibration curves revealed good correlation of CSS between the actual observation and the nomogram. Then, the DCA showed greater net benefits than that of treat-all or treat-none at all time points. A novel risk grouping system was established for CSS that can readily divide all patients into three distinct risk groups.Conclusion: The proposed nomogram obtained more precision prognostic prediction for patients with initially-diagnosed primary spinal and pelvic tumors.Level Of Evidence: 3. [ABSTRACT FROM AUTHOR]

The polyacrylamide (AAm)-chitosan (CS)-N,N'-methylene bisacrylamide (Bis) bilayer shape memory hydrogel actuators with high mechanical strength were successfully prepared via efficient in-situ free radical polymerization. The hydrogels exhibited high swelling and shape memory bending/unbending properties. Increasing Bis contents enhanced the crosslinking density and maintained the hydrophilic property of hydrogels, providing the microstructure and swelling anisotropy for construction of bilayer structure. Attributed to the enough polymerization on interface, bilayer hydrogels owned high bonding strength. With the increase of Bis content, the swelling bending degree of bilayer hydrogel actuators increased. Based on the mechanism of formation and disappearance of coordination of CS-metal ion, bilayer hydrogel actuators exhibited efficient shape memory property. The intelligent swelling and shape memory properties enriched the multiply deformation patterns of bilayer shape memory hydrogels, providing the potential applications in soft actuators, soft sensors and medical carriers. [ABSTRACT FROM AUTHOR]

Deep learning is a powerful tool for domain adaptation by learning robust high-level domain invariant representations. Recently, adversarial domain adaptation models are applied to learn representations with adversarial training manners in feature space. However, existing models often ignore the generation process for domain adaptation. To tackle this problem, deep cycle autoencoder (DCA) is proposed that integrates a generation procedure into the adversarial adaptation methods. The proposed DCA consists of four parts, a shared encoder, two separated decoders, a discriminator and a linear classifier. With the labelled source images and unlabelled target images as inputs, the encoder extracts high-level representations for both source and target domains, and the two decoders reconstruct the inputs with the latent representations separately. The shared encoder is pitted against the discriminator; the encoder tries to confuse the discriminator while discriminator aims at distinguishing which domain the latent representations come from. DCA adopts both adversarial loss and maximum mean discrepancy loss in the latent space for distribution alignment. The classifier is trained with both the source original and reconstructed image representations. Extensive experimental results have demonstrated the effectiveness and the reliability of the proposed methods. [ABSTRACT FROM AUTHOR]

With the development of technology, an unmanned aircraft system will play a significant role in Internet of things based on 5G. Avionics system is an important part of the unmanned aircraft system, and the reliability of the avionics system directly determines the ability to perform missions. This article deals with the problem of reliability modeling with unmanned aircraft system avionics systems built on Internet of things in the 5G scenario. First, based on the composition of the avionics system, the network structure of the unmanned aircraft system avionics system is presented. Then, to evaluate the reliability, a task model of the unmanned aircraft system avionics system is proposed. Finally, an illustration of unmanned aircraft system reliability performing reconnaissance is also presented. By analyzing the task performance, it is shown that redundancy design of the units can improve the reliability of the unmanned aircraft system avionics system. [ABSTRACT FROM AUTHOR]

Abnormal physiological conditions provide an ideal stimulus for the design of responsive hydrogels which function as controlled and site-specific release of drugs. Here, an injectable reactive oxygen species (ROS) responsive selfhealing hydrogel based on tetra-poly(ethylene glycol)-b-oligo (l-methionine) (t-PEG56-b-OMethn) synthesized by a novel and facile method is reported. The hydrophobic interactions between the side chains of l-methionine make the polymer chains crosslinked and lead to the formation of hydrogels which can be injected and self-healed, meanwhile, the cross-linker also provides a hydrophobic domain to encapsulate Dox. In presence of ROS, the side chain of l-methionine can be oxidized to methionine sulfoxide. The side chain of l-methionine is changed accordingly from hydrophobic to hydrophilic. As a result, both the hydrophobic domain and the hydrogel itself are destroyed. The controlled release of Dox by ROS at site-specific is realized. The excellent biocompatibility of hydrogel based on t-PEG56-b-OMethn indicates the door of the potential application in controlled release of drug in a truly physiological environment. [ABSTRACT FROM AUTHOR]

Berths and quay cranes (QCs) are two important resources in container terminals. Although good planning can shorten ship turnaround times, berths and QCs are interdependent. In the handling process, the number of QCs assigned to a ship may vary because of other ships berthing or departing. This variation, in turn, affects the QCs' efficiency and the ship handling time, thus affecting the following ships' berth-QC planning. In this article, a new mixed-integer programming model for simultaneous continuous berth-allocation and time-varying specific QC assignment is established. Furthermore, a genetic algorithm based on spatiotemporal conflict is designed for the model. Numerical experiments show that the proposed method can provide a reasonable solution for such an NP-hard problem in a reasonable time. In addition, the important parameters affecting the results are analysed. [ABSTRACT FROM AUTHOR]

A number of strategies have been developed to mine novel natural products based on biosynthetic gene clusters and there has been dozens of successful cases facilitated by the development of genomic sequencing. During our study on biosynthesis of the antitumor polyketide kosinostatin (KST), we found that the genome of Micromonospora sp. TP-A0468, the producer of KST, contains other potential polyketide gene clusters, with no encoded products detected. Deletion of kst cluster led to abolishment of KST and the enrichment of several new compounds which were isolated and characterized as 16-demethylrifamycins (3-6). Transcriptional analysis demonstrated that the expression of the essential genes related to the biosynthesis of 3-6 was in comparable level in wild type and kst cluster deletion strain. This indicates that the accumulation of these compounds was due to the redirection of metabolic flux rather than transcriptional activation. Genetic disruption, chemical complementation and bioinformatic analysis revealed that the production of 3-6 was accomplished by crosstalk between two distantly placed polyketide gene clusters pks3 and M-rif. This finding not only enriches the analogue pool and biosynthetic diversity of rifamycins, but also provides an auxiliary strategy for natural product discovery through genome mining in polyketide-producing microorganisms. Importance Natural products are essential in the development of novel clinically-used drugs. Discovering new natural products and modifying known compounds are still the two main ways to generate new 37 candidates. Here, we have discovered several rifamycins with varied skeleton by redirecting the metabolic flux from the predominant polyketide biosynthetic pathway to the rifamycin pathway in the marine actinomycetes species Micromonospora sp. TP-A0468. Rifamycins are indispensable chemotherapeutics in the treatment of various diseases such as tuberculosis, leprosy and AIDS-related mycobacterial infections. This work exemplifies a useful method for the discovery of cryptic natural products in genome-sequenced microbes. Moreover, the 16-demethylrifamycins and their genetically manipulable producer provides a new opportunity in the construction of novel rifamycin derivates to aid in the defense against the ever-growing drug-resistance of Mycobacterium tuberculosis. [ABSTRACT FROM AUTHOR]

Considering that the current low-stress cropping method for large-diameter metal bar has the disadvantages of large cutting force and drastic change of loading force, a new low-stress cropping method is proposed based on the co-induced crack initiation by rotating-bending and slotting. Based on the strength theory and fatigue damage theory, the dynamic bending cutting model is established, proving that the prestressed bending action reduces the slotted cutting and cracking forces. The formula of main cutting force during slotting considering rotation speed under the prestressed action is obtained by establishing simulation model combined with the experimental platform of the prestressed rotating-bending cutting and cracking process. Three types of initiation crack are proposed, and the reasonable process parameters for effective connection of slotting and ideal crack initiation type are obtained. The experimental results of 45 steel bar show that the cutting force is reduced to only 75.79% of the traditional cutting slotting, and the crack initiation force is reduced to only 1.88% of the traditional shearing force. Similarly, the test results of Q235 steel, 6061 aluminum alloy, and 304 austenitic stainless steel also show that the cutting force of prestressed slotting is reduced and the slotting and cracking connection can be realized, which can meet the requirements of low-stress slotting and cracking of the bar with large diameter. Investigation of co-induced crack initiation process by prestressed slotting and rotating-bending in low-stress cropping [ABSTRACT FROM AUTHOR]

Outer ear infections (OEs) affect millions of people each year and are associated with significant medical costs.The usage of multiple antibiotics to treat ear contamination is a concern because it can have an environmental impact, especially on soil and water.The increased use of antibiotics has exposed bacterial ecosystems to high concentrations of antibiotic residues.Although there have been efforts to minimize the impact of antibiotics, adsorption methods have yielded better and more viable results, and carbon-based materials are effective for environmental remediation.Graphene oxide (GO) is a versatile material used in various applications such as nanocomposites, antibacterial agents, photocatalysis, electronics, and biomedicine.GO can act as an antibiotic carrier and affect the antibacterial efficacy of antibiotics.However, the processes responsible for the antibacterial activity of GO and antibiotics in treating ear infections are unknown.This study investigates the effect of GO on the antibacterial activity of tetracycline (TT) against Escherichia coli (E.coli)-negative bacteria.Artificial Neural Network-Genetic Algorithm (ANN-GA) was applied to analyze data on the effectiveness of different doses and combinations of graphene oxide and antibiotics in treating ear infections.This study could help identify the most effective treatment protocols and potentially reduce the risk of antibiotic resistance.The R-squared (R2) value, RMSE, and MSE all fall within the proper levels for fitting criteria, with R2 ≥ 0.97 (97%), RMSE ≤ 0.036064, and MSE ≤ 0.00199 (6% variance).The outcomes showed high antimicrobial activity, resulting in a 5-log decline of E.coli.In experiments, GO was shown to coat the bacteria, interfere with their cell membranes, and aid in the prevention of bacterial growth, although this effect was somewhat weaker for E.coli.The concentration and duration at which bare GO can kill E.coli are both important factors.The antibacterial activity of antibiotics can be either boosted or reduced by the presence of GO, depending on the GO's interaction with the antibiotic, the GO's contact with the microbe, and the sensitivity of the bacteria to the antibiotic.The antibacterial efficiency of the combination of GO and antibiotics varies depending on the specific antibiotic and microorganism being targeted. Schematic view of GO synthesis by chemical oxidation using Hummer's methods, Brodie's, and Staudenmaier's (Adetayo and Runsewe, 2019). [Display omitted] • One-spot hydrothermal synthesis of graphene oxide nanoparticles. • GO nanoparticles enhance antibacterial efficacy of antibiotics. • AI-enhanced approach for treatment of ear contamination. • GO aids in environmental remediation with adsorption methods. • ANN-GA analysis for identifying effective treatment protocols. [ABSTRACT FROM AUTHOR]

Crystal structure of (4-aminobenzoato-²O,O')-[5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-4N,N',N",N"']nickel(II) perchlorate monohydrate, C23H44ClN5NiO7. [Extracted from the article]

Gust load alleviation using computational fluid dynamics as source of the aerodynamic predictions is carried out in the time domain. To this goal, an aeroservoelastic reduced-order model is generated. The model capitalizes on two key aspects: a dimensional reduction through proper orthogonal decomposition, further enhanced via balanced truncation, and an analytically derived mechanism to reproduce the gust effects in the reduced-order model. The compact model in state-space form thus obtained was then used for control design synthesis. Assuming that information on the structural motion only is accessible for feedback, a linear quadratic regular was designed first on the reduced model and then validated on the large computational model. Results are presented for two configurations: an aerofoil and the modified AGARD 445.6 wing, both with a trailing-edge control surface. Studies are presented for the gust response to discrete gusts and continuous turbulence. In particular, for the latter, the standard deviation of the loads and the structural motion was reduced as much as 77%. [ABSTRACT FROM AUTHOR]

1,6-O,O-Diacetylbritannilactone is a natural sesquiterpene lactone isolated from Inula britannica that has displayed cytotoxic effects against several human cancer cell lines. In this study, a selective and sensitive liquid chromatography-tandem mass spectrometry (LC-MS-MS) method was developed for determination of 1,6-O,O-diacetylbritannilactone in rat plasma. Chromatographic separation was achieved on an Agilent C18 column (4.6mm × 75 mm, 3.5 μm) with methanol and water (80:20, v/v) as the mobile phase. An ESI source was applied and operated in positive ion mode; selected-reaction monitoring was used for quantification using target fragment ions m/z 373.2→312.9 for 1,6-O,O-diacetylbritannilactone and m/z 331.2→144.1 for the IS. Calibration plots were linear in the range of 1.5-1350 ng/mL for 1,6-O,O-diacetylbritannilactone in rat plasma. Intra- and inter-day precisions were <8.5%, and the accuracy ranged from -2.7 to 12.8%. The LC-MS-MS method was successfully applied in a pharmacokinetic study of 1,6-O,O-diacetylbritannilactone in rats. [ABSTRACT FROM AUTHOR]

Fault diagnosis is critical in PHM (Prognostics and Health Management) of machine tools due to its great significance in such efforts as prolonging lifespan, improving production efficiency, and reducing production costs. For machine tool manufacturers, a general fault diagnosis method and a software framework are needed to construct fault diagnosis systems for various machine tools and fault types, or the same type of machine tools under various life cycles, working conditions, and operating environments. A configurable method for fault diagnosis knowledge of machine tools (CMFDK-MT) is thus proposed in this paper. Firstly, an ontology-based fault diagnosis method for machine tools and an improved process of fault diagnosis with knowledge bases are introduced. Based on these, a framework of a knowledge-based configurable fault diagnosis platform for machine tools (KCFDP-MT) is designed. KCFDP-MT supports explicit knowledge representation with formal semantics, efficient knowledge utilization, and efficient integration of various fault diagnosis methods and technologies. Then, the configuration approaches for fault diagnosis activities, namely fault detection, identification, diagnosis, and solving, are studied respectively. The configuration and implementation methods of the KCFDP-MT framework are also presented. Finally, a prototype system is constructed for a CNC hobbing machine tool. Two cases of rolling bearing and gear based on signal processing are carried out to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Resveratrol oligomers (REVs), a major class of stilbenoids, are biosynthesized by regioselective oxidative coupling of two to eight units of resveratrol monomer. Due to their unique structures and pleiotropic biological activities, natural product chemists are increasingly focusing on REVs in the last few decades. This study presents a detailed and thorough examination of REVs, including chemical structures, natural resources, and biological activities, during the period of 2010-2017. Ninety-two new REVs compounds, including 39 dimers, 23 trimers, 13 tetramers, six resveratrol monomers, six hexamers, four pentamers, and one octamer, have been reported from the families of Dipterocarpaceae, Paeoniaceae, Vitaceae, Leguminosae, Gnetaceae, Cyperaceae, Polygonaceae Gramineae, and Poaceae. Amongst these families, Dipterocarpaceae, with 50 REVs, accounts for the majority, and seven genera of Dipterocarpaceae are involved, including Vatica, Vateria, Shorea, Hopea, Neobalanocarpus, Dipterocarpus, and Dryobalanops. These REVs have shown a wide range of bioactivities. Pharmacological studies have mainly focused on potential efficacy on tumors, bacteria, Alzheimer's disease, cardiovascular diseases, and others. The information updated in this review might assist further research and development of novel REVs as potential therapeutic agents. [ABSTRACT FROM AUTHOR]

The result of processing the residual static correction has a profound effect on the finished quality of a reconstructed image. Static correction using wave reflection techniques cannot be guaranteed when the signal-to-noise ratio is too low or the residual static correction is larger than a half-wavelength of the refracted waves. A novel method based on first arrivals in a 3D shot-receiver united domain is presented to handle these situations. This method fits and smooths the first breaks in a robust 3D way to calculate the shot and receiver static. This method has a lower sensitivity to first arrivals than traditional methods. Applications on synthetic and real data show very high performance of the presented algorithm. [ABSTRACT FROM AUTHOR]

This work verifies that the W foil could be successfully welded on Cu through conventional explosive welding, without any cracks. The microstructure was observed through scanning electron microscopy (SEM), optical microscopy and energy-dispersive X-ray spectrometry (EDS). The W/Cu interface exhibited a wavy morphology, and no intermetallic or transition layer was observed. The wavy interface formation, as well as the distributions of temperature, pressure and plastic strain at the interface were studied through numerical simulation with Smoothed Particle Hydrodynamics (SPH). The welding mechanism of W/Cu was analyzed according to the numerical results and experimental observation, which was in accordance with the indentation mechanism proposed by Bahrani. [ABSTRACT FROM AUTHOR]

We examined aggression differences among nonoffender, onset-offender, and recidivist migrant youth in China using explicit and implicit measures. From 2011 to 2015, data were collected via face-to-face surveys and the Implicit Association Test (IAT). Male migrant youth (N = 227; 106 nonoffenders, 78 onset-offenders, and 43 recidivists) completed the Chinese version of the Buss and Perry Aggression Questionnaire, and 125 male migrant youth (68 nonoffenders, 31 onset-offenders, and 26 recidivists) performed two IATs assessing implicit attitudes and implicit self-concepts about aggression. The results showed that the IAT was reliable in an Asian context with offenders, and that the onset-offenders demonstrated greater aggression compared with those in the recidivist and nonoffender groups. Our findings suggest that onset-offenders may have more accurate self-awareness than do recidivists and incarceration may influence attitudes toward aggression in a positive way. Such knowledge is important for interventions that target juvenile delinquency. [ABSTRACT FROM AUTHOR]

DNA methylation at CpG rich regions often occurs at tumor suppressor gene promoters, resulting in reduced gene expression and final carcinogenesis. Hypermethylation of tumor suppressor genes, including DAPK-1 and RASSF-1α genes, have been found in patients with bladder carcinoma (BC) in some western countries. Reactive oxygen species (ROS) was reported to play a causative role in gene hypermethylation. In this study, we detected the methylation status and expression of DAPK1 and RASSF-1α genes in tissue samples from Chinese BC patients, using methylation-specific PCR, reverse transcription PCR and western blotting. Further, we examined the ability of dioscin, a natural antioxidant, to regulate methylation status and expression of DAPK-1 and RASSF-1α genes in BC cell lines. In our results, DAPK-1 and RASSF-1α genes showed higher methylation level and lower express level in BC tissues than matched normal tissues. Treatment with dioscin decreased viability of BC 5637 and T24 cells, but not non-cancer bladder epithelial cell, SV-HUC-1. Dioscin triggered demethylation of DAPK1 and RASSF-1α genes in T24 cells and increased the gene and protein expression in 5637 and T24 cells. Both dioscin and substituted antioxidants (N-acetyl cysteine and Vitamin E) decreased intracellular ROS, but the effect of dioscin was abolished by adding H2O2. Similar to dioscin, the substituted antioxidants also induced the gene demethylation and T24 cell apoptosis. Co-treatment with dioscin and H2O2 had no such effects. Collectively, dioscin induces demethylation of DAPK-1 and RASSF-1α genes via the antioxidant capacity, resulting in apoptosis of bladder cancer T24 cells or inhibitory cell viability. [ABSTRACT FROM AUTHOR]

We conducted 2 studies to investigate whether or not individuals consider a task to be competitive even when their competitors are imagined. We used a 2-choice reaction time task with compatible and incompatible flankers, which was completed by 64 university undergraduates (Mage = 21.4 years; range: 19-23 years). In Study 1, participants completed their task in both individual and competitive conditions. In Study 2, participants took turns to compete with the experimenter side by side and then in a different room. Results indicated that the joint flanker effect occurred, whether or not the competitor was visible or invisible. These findings confirm earlier results that interdependency affects people's behavior even in a competitive context, and promote understanding of the basic mechanism underlying competitive action. [ABSTRACT FROM AUTHOR]

Background: The maize kernel row number (KRN) is a key component that contributes to grain yield and has high broad-sense heritability (H2). Quantitative trait locus/loci (QTL) mapping using a high-density genetic map is a powerful approach to detecting loci that are responsible for traits of interest. Bulked segregant ribonucleic acid (RNA) sequencing (BSR-seq) is another rapid and cost-effective strategy to identify QTL. Combining QTL mapping using a high-density genetic map and BSR-seq may dissect comprehensively the genetic architecture underlying the maize KRN. Results: A panel of 300 F2 individuals derived from inbred lines abe2 and B73 were genotyped using the specific-locus amplified fragment sequencing (SLAF-seq) method. A total of 4,579 high-quality polymorphic SLAF markers were obtained and used to construct a high-density geneticmap with a total length of 2,123 centimorgan (cM) and an average distance between adjacent markers of 0.46 cM. Combining the genetic map and KRN of F2 individuals, four QTL (qKRN1, qKRN2, qKRN5, and qKRN8-1) were identified on chromosomes 1, 2, 5, and 8, respectively. The physical intervals of these four QTL ranged from 4.36 Mb for qKRN8-1 to 7.11 Mb for qKRN1 with an average value of 6.08 Mb. Based on high-throughput sequencing of two RNA pools bulked from leaves of plants with extremely high and low KRNs, two QTL were detected on chromosome 8 in the 10-25 Mb (BSR_QTL1) and 60-150 Mb (BSR_QTL2) intervals. According to the physical positions of these QTL, qKRN8-1 was included by BSR_QTL2. In addition, qKRN8-1 was validated using QTL mapping with a recombinant inbred lines population that was derived from inbred lines abe2 and B73. Conclusions: In this study, we proved that combining QTL mapping using a high-density genetic map and BSR-seq is a powerful and cost-effective approach to comprehensively revealing genetic architecture underlying traits of interest. The QTL for the KRN detected in this study, especially qKRN8-1, can be used for performing fine mapping experiments and marker-assisted selection in maize breeding. [ABSTRACT FROM AUTHOR]

Deoxypodophyllotoxin (DPPT) is extracted and separated from citrus-related plants, including Podophyllum (P.) peltatum, P. pleianthum, P. emodi (also called P. hexandrum) and Diphylleia grayi. DPPT has significant antitumor and antiviral activity. However, due to its strong toxicity and side effects, its use is limited in practical applications. The in vitro antitumor efficacy of DPPT on human prostate cancer (PCa) cells remains to be determined. The present study investigated the anticancer effect of DPPT on human PCa cells and its potential mechanism. The data revealed that DPPT markedly reduced cell proliferation and activated the caspase-3 expression level by an increase in apoptotic cell death in DU-145 cells. In addition, treatment with DPPT markedly downregulated the levels of phosphorylated Akt and activated the p53/B-cell lymphoma 2 associated X protein (Bax)/phosphatase and tensin homolog (PTEN) signaling pathway in DU-145 cells, suggesting that caspase-mediated pathways were involved in DPPT-induced apoptosis. The present study suggested the role of DPPT as a novel chemotherapeutic drug for human PCa, which may function through the Akt/p53/Bax/PTEN signaling pathway. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the role of recombinant human neuregulin-1β (rhNRG-1β) in the repair of the radiation-induced damage of myocardial cells and the underlying mechanism. Rats were divided into the radiotherapy alone group, the rhNRG-1β group (radiotherapy with rhNRG-1β treatment) and the Herceptin group (radiotherapy with Herceptin treatment), and their myocardial cells were analyzed. The morphology of the myocardial cells was observed under an optical microscope, and the expression of γ-H2AX and p53 was analyzed using immunohistochemistry and western blot analysis. Damage to the myocardial cells was identified in the three groups following radiation treatment, which was identified by cell swelling and altered morphology. The integrated optical density values of γ-H2AX in the radiotherapy alone, rhNRG-1β and Herceptin groups were 50.96±5.548, 27.63±10.61 and 76.12±2.084, respectively. The OD of the radiotherapy alone group was significantly higher than that of the rhNRG-1β treated group (P<0.0001), and the value of the Herceptin group was significantly higher than that of the radiotherapy alone group (P<0.0001). The p53 level in the rhNRG-1β group was less than that of the radiotherapy alone group (P<0.001), and was higher in the Herceptin group compared with the radiotherapy alone group (P<0.0001). Thus, rhNRG-1β can ameliorate radiotherapy-induced myocardial cell injury, predominantly by enhancing myocardial cell DNA repair, inhibiting cell apoptosis and improving myocardial function. The results of this study in myocardial cells suggest that patients with thoracic cancer may benefit from treatment with rhNRG-1β for the repair of the radiation-induced damage of myocardial cells. [ABSTRACT FROM AUTHOR]

A voltage transformer, as voltage signal detection equipment, plays an important role in a power system. Presently, more and more electric power systems are adopting potential transformer and capacitance voltage transformers. Transformers are often large in volume and heavyweight, their insulation design is difficult, and an iron core or multi-grade capacitance voltage division structure is generally adopted. As a result, the detection accuracy of transformer is reduced, a huge phase difference exists between detection signal and voltage signal to be measured, and the detection signal cannot accurately and timely reflect the change of conductor voltage signal to be measured. By aiming at the current problems of electric transformation, based on electrostatic induction principle, this paper designed a non-contact voltage sensor and gained detection signal of the sensor through electrostatic coupling for the electric field generated by electric charges of the conductor to be measured. The insulation structure design of the sensor is simple and its volume is small; phase difference of sensor measurement is effectively reduced through optimization design of the electrode; and voltage division ratio and measurement accuracy are increased. The voltage sensor was tested on the experimental platform of simulating three-phase transmission line. According to the result, the designed non-contact voltage sensor can realize accurate and real-time measurement for the conductor voltage. It can be applied to online monitoring for the voltage of three-phase transmission line or three-phase distribution network line, which is in accordance with the development direction of the smart grid. [ABSTRACT FROM AUTHOR]

Campeiostachys nutans (Griseb.) J. L. Yang, B. R. Baum et C. Yen is a widely cultivated grass that is used for forage. Considering its limited genomic resources, there is a strong need to increase the available data on this species, which would allow for the identification of genes useful for molecular breeding and lead to increased crop quality and productivity. Complementary DNA (cDNA) samples from 11 different tissues were sequenced using Illumina paired-end sequencing. A total of 106,220 unigenes were obtained via de novo assembly, and 82,863 (78.01%) unigenes were annotated based on similarity searches using known proteins. In addition, 8727 expressed sequence tag-simple-sequence repeat (EST-SSR) loci were identified. A subset of 480 EST-SSRs was randomly synthesized and screened for validation across a panel of 16 C. nutans accessions using 48 individual plants, with 113 polymorphic EST-SSRs generating 439 alleles. The number of alleles, observed heterozygosity, expected heterozygosity, and polymorphism information content ranged from three to nine, 0.00 to 1.00, 0.51 to 0.84, and 0.39 to 0.82, respectively. Overall, the C. nutans transcriptomic sequences generated in this study provide both an important platform that will facilitate gene discovery for functional genomic studies and EST-SSR markers for use in breeding. [ABSTRACT FROM AUTHOR]

Responding to stimuli, nucleotide-binding domain and leucine-rich repeat-containing proteins (NLRs) oligomerize into multiprotein complexes, termed inflammasomes, mediating innate immunity. Recognition of bacterial pathogens by NLR apoptosis inhibitory proteins (NAIPs) induces NLR family CARD domain-containing protein 4 (NLRC4) activation and formation of NAIP-NLRC4 inflammasomes. The wheel-like structure of a PrgJ-NAIP2-NLRC4 complex determined by cryogenic electronmicroscopy at 6.6 angstrom reveals that NLRC4 activation involves substantial structural reorganization that creates one oligomerization surface (catalytic surface). Once activated, NLRC4 uses this surface to catalyze the activation of an inactive NLRC4, self-propagating its active conformation to form the wheel-like architecture. NAIP proteins possess a catalytic surface matching the other oligomerization surface (receptor surface) of NLRC4 but not those of their own, ensuring that one NAIP is sufficient to initiate NLRC4 oligomerization. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate local bone formation following systemic administration of parathyroid hormone (1–34), a surgically implanted synthetic β-tricalcium phosphate bone biomaterial serving as a matrix to support new bone formation. Twelve weeks after bilateral ovariectomy, all rats underwent bone defect in the distal femurs, and β-tricalcium phosphate was implanted into critical sized defects. After defect operation, all animals were randomly divided into four groups and received following subcutaneous injections until death at four and eight weeks: sham rats (group ST); sham rats + parathyroid hormone, 30 µg/kg, three times a week (group SPT); OVX rats (group OT); and OVX rats + parathyroid hormone (group OPT). The distal femurs of rats were harvested for evaluation. The treatment group demonstrating the highest levels of new bone formation was the defects treated with parathyroid hormone as assessed by micro-computed tomography, biomechanical strength, and histological analysis for sham rats. Furthermore, parathyroid hormone showed a stronger effect on accelerating the degradation of β-tricalcium phosphate. Osteoporosis can limit the function of parathyroid hormone and/or β-tricalcium phosphate. The results from our study demonstrate that combination of parathyroid hormone and β-tricalcium phosphate brings better effect to bone tissue repair in non-osteoporosis and/or osteoporosis status. [ABSTRACT FROM AUTHOR]

An efficient multi-component reaction to synthesize multi-substituted 1,3-oxazolidine compounds of high optical purity was described. All the products were well-characterized and the absolute configuration of one chiral center was determined. The plausible mechanism was proposed and a kinetic resolution of epoxides process was confirmed. [ABSTRACT FROM AUTHOR]

Malignant gliomas are the most common type of primary malignancy of the central nervous system, with a poor prognosis. The therapeutic options for malignant gliomas are limited and far from satisfactory, and novel treatment strategies are urgently required to improve the outcome of the disease. Insulin-like growth factor (IGF)/IGF-1 receptor (IGF-1R) signaling pathway regulates cell proliferation, motility and survival. The dysregulation of this signaling pathway has been implicated in the development of malignant gliomas. In the present study, GSK1904529A, a small molecule inhibitor of IGF-1R, suppressed glioma cell viability, induced glioma cell apoptosis and inhibited glioma cell migration in vitro. In addition, GSK1904529A inhibited glioma tumor growth and induced tumor cell apoptosis in vivo. In conclusion, the results of the present study suggested GSK1904529A as a promising agent for the treatment of malignant glioma. [ABSTRACT FROM AUTHOR]

Carvedilol is the current β-blocker of choice for suppressing ventricular tachyarrhythmia (VT). However, carvedilol's benefits are dose-limited, attributable to its potent β-blocking activity that can lead to bradycardia and hypotension. The clinically used carvedilol is a racemic mixture of β-blocking S-carvedilol and non-β-blocking R-carvedilol. We recently reported that novel non-β-blocking carvedilol analogues are effective in suppressing arrhythmogenic Ca2+ waves and stress-induced VT without causing bradycardia. Thus, the non-β-blocking R-carvedilol enantiomer may also possess this favourable anti-arrhythmic property. To test this possibility, we synthesized R-carvedilol and assessed its effect on Ca2+ release and VT. Like racemic carvedilol, R-carvedilol directly reduces the open duration of the cardiac ryanodine receptor (RyR2), suppresses spontaneous Ca2+ oscillations in human embryonic kidney (HEK) 293 cells, Ca2+ waves in cardiomyocytes in intact hearts and stress-induced VT in mice harbouring a catecholaminergic polymorphic ventricular tachycardia (CPVT)-causing RyR2 mutation. Importantly, Rcarvedilol did not significantly alter heart rate or blood pressure. Therefore, the non-β-blocking R-carvedilol enantiomer represents a very promising prophylactic treatment for Ca2+ - triggered arrhythmia without the bradycardia and hypotension often associated with racemic carvedilol. Systematic clinical assessments of R-carvedilol as a new anti-arrhythmic agent may be warranted. [ABSTRACT FROM AUTHOR]

Voltage sensors are an important part of the electric system. In service, traditional voltage sensors need to directly contact a high-voltage charged body. Sensors involve a large volume, complex insulation structures, and high design costs. Typically an iron core structure is adopted. As a result, ferromagnetic resonance can occur easily during practical application. Moreover, owing to the multilevel capacitor divider, the sensor cannot reflect the changes of measured voltage in time. Based on the electric field coupling principle, this paper designs a new voltage sensor; the unipolar structure design solves many problems of traditional voltage sensors like the great insulation design difficulty and high costs caused by grounding electrodes. A differential signal input structure is adopted for the detection circuit, which effectively restrains the influence of the common-mode interference signal. Through sensor modeling, simulation and calculations, the structural design of the sensor electrode was optimized, miniaturization of the sensor was realized, the voltage division ratio of the sensor was enhanced, and the phase difference of sensor measurement was weakened. The voltage sensor is applied to a single-phase voltage class line of 10 kV for testing. According to the test results, the designed sensor is able to meet the requirements of accurate and real-time measurement for voltage of the charged conductor as well as to provide a new method for electricity larceny prevention and on-line monitoring of the power grid in an electric system. Therefore, it can satisfy the development demands of the smart power grid. [ABSTRACT FROM AUTHOR]

Background: Many researches have investigated the changes associated with immobilization-induced osteoarthritis (OA). However, there are only few studies focusing on the effect of unilateral knee immobilization on cartilage matrix changes in the contralateral mobile knee. The aim of the present study was to investigate the influence of immobilization on the cartilage matrix in the contralateral mobile knees in a rabbit model of OA induced by immobilization.Methods: Right knees (experimental knees) of eighteen mature female rabbits were immobilized at an extension of 180° with orthopedic casting tape for 2, 4, or 8 weeks. Left knees (contralateral knees) of the immobilized rabbits were not subjected to immobilization. The knees of six non-immobilized rabbits were designated as control knees. Following immobilization, cartilage specimens from the medial femoral condyle underwent macroscopic, histological, immunohistochemical, and biochemical evaluations.Results: Roughness of cartilage surface was detected in the experimental knees at 2 weeks, and cartilage degeneration was further developed. In the contralateral knee, cartilage showed degenerative changes after 4 weeks. Safranin-O staining and glycosaminoglycan (GAG) contents were reduced in the experimental knees following immobilization and in the contralateral intact knees after 4 and 8 weeks. Type II collagen staining was gradually reduced, type I collagen accumulation was obviously detected in the upper and middle layers of cartilage in experimental knees after 8 weeks, and the collagen orientation was gradually disorganized in both knees at 4 and 8 weeks. For both experimental and contralateral knees, collagen contents were significantly decreased at 8 weeks, and Mankin and Osteoarthritis Research Society International (OARSI) scores increased over time.Conclusion: OA developed in the contralateral intact knee with the progress of OA in the immobilized knee in a rabbit model of immobilization-induced OA. [ABSTRACT FROM AUTHOR]

Direct numerical simulations with an immersed boundary-lattice Boltzmann method are used to investigate the effects of particle rotation on flows past random arrays of mono-disperse spheres at moderate particle Reynolds numbers. This study is an extension of a previous study of the authors [Q. Zhou and L.-S. Fan, "Direct numerical simulation of low-Reynolds-number flow past arrays of rotating spheres," J. Fluid Mech. 765, 396-423 (2015)] that explored the effects of particle rotation at low particle Reynolds numbers. The results of this study indicate that as the particle Reynolds number increases, the normalized Magnus lift force decreases rapidly when the particle Reynolds number is in the range lower than 50. For the particle Reynolds number greater than 50, the normalized Magnus lift force approaches a constant value that is invariant with solid volume fractions. The proportional dependence of the Magnus lift force on the rotational Reynolds number (based on the angular velocity and the diameter of the spheres) observed at low particle Reynolds numbers does not change in the present study, making the Magnus lift force another possible factor that can significantly affect the overall dynamics of fluid-particle flows other than the drag force. Moreover, it is found that both the normalized drag force and the normalized torque increase with the increase of the particle Reynolds number and the solid volume fraction. Finally, correlations for the drag force, the Magnus lift force, and the torque in random arrays of rotating spheres at arbitrary solids volume fractions, rotational Reynolds numbers, and particle Reynolds numbers are formulated. [ABSTRACT FROM AUTHOR]

An unprecedented organocatalytic asymmetric Michael/cyclization cascade reaction of 3-isothiocyanato oxindoles and 3-nitroindoles has been disclosed. A wide range of enantioenriched polycyclic spirooxindoles, containing three contiguous chiral centers with two of them having quaternary stereocenters, could be smoothly obtained with satisfactory results (up to 99% yield, >99:1 dr, and 96% ee). This method is very promising because the reaction is scalable, and the versatile transformations of the products into other spirocyclic oxindoles are also feasible. [ABSTRACT FROM AUTHOR]

Glioblastoma is one of the most common malignant tumors in the nervous system in both adult and pediatric patients. Studies suggest that abnormal activation of receptor tyrosine kinases contributes to pathological development of glioblastoma. However, current therapies targeting tyrosine kinase receptors have poor therapeutic outcomes. Here, we examined anticancer effects of ponatinib, a multi-targeted tyrosine kinase inhibitor, on glioblastoma cells both in the U87MG cell line and in the mouse xenograft model. We showed that ponatinib treatment reduced cell viability and induced cell apoptosis in a dose-dependent manner in U87MG cells. In addition, ponatinib suppressed migration and invasion of U87MG cells effectively. Furthermore, ponatinibtreated tumors showed an obvious reduction of tumor volume and an increase of apoptosis as compared with vehicle-treated tumors in the mouse xenograft model. These findings support a potential application of ponatinib as a chemotherapeutic option against glioblastoma cells. [ABSTRACT FROM AUTHOR]

A bifunctional thiourea-tertiary amine-catalyzed enantioselective double Michael reaction of Nazarov reagents and alkylidene azlactones was realized. Using this protocol, a series of optically active spiro-fused cyclohexanone/5-oxazolone derivatives, bearing three consecutive chiral centers including one spiro quaternary chiral center, were obtained in good yields with good stereoselectivities (up to 93% yield, 99:1 dr, and 91% ee). The synthetic utility of the products for the formation of chiral cyclic quaternary amino-acid derivatives was also demonstrated. [ABSTRACT FROM AUTHOR]

We used a face similarity task with event-related potentials (ERPs) in a study conducted with 22 individuals in order to examine the processing of identity information. During the evaluation task, significant variations in the late negative potential were elicited by different identity contexts of couples versus strangers. By contrast, the face-specific N170 component was not significantly affected by variations in identity context. In addition, participants' behavioral data were significantly influenced by the task instructions, but not by the true relationship of the couple. Together, ERP and behavioral results suggest that the evaluation of face similarity with identity information occurs at a later stage. [ABSTRACT FROM AUTHOR]

Data aggregation is an important technique for reducing the energy consumption of sensor nodes in wireless sensor networks (WSNs). However, compromised aggregators may forge false values as the aggregated results of their child nodes in order to conduct stealthy attacks or steal other nodes' privacy. This paper proposes a Secure-Enhanced Data Aggregation based on Elliptic Curve Cryptography (SEDA-ECC). The design of SEDA-ECC is based on the principles of privacy homomorphic encryption (PH) and divide-and-conquer. An aggregation tree disjoint method is first adopted to divide the tree into three subtrees of similar sizes, and a PH-based aggregation is performed in each subtree to generate an aggregated subtree result. Then the forged result can be identified by the base station (BS) by comparing the aggregated count value. Finally, the aggregated result can be calculated by the BS according to the remaining results that have not been forged. Extensive analysis and simulations show that SEDA-ECC can achieve the highest security level on the aggregated result with appropriate energy consumption compared with other asymmetric schemes. [ABSTRACT FROM AUTHOR]

Data aggregation is an important method to reduce the energy consumption in wireless sensor networks (WSNs); however, it suffers from the security problems of data privacy and integrity. Existing solutions either have large communication and computation overheads or only produce inaccurate results. This paper proposes a novel secure data aggregation scheme based on homomorphic primitives in WSNs (abbreviated as SDA-HP).The scheme adopts a symmetric-key homomorphic encryption to protect data privacy and combines it with homomorphic MAC synchronically to check the aggregation data integrity. It compares the scheme with the previously known methods such as SIES, iPDA, and iCPDA in terms of the data privacy protection efficiency, integrity performance, computation overhead, communication overhead, and data aggregation accuracy. Simulation results and performance analysis show that our SDA-HP requires less communication and computation overheads than previously known methods and can effectively preserve data privacy, check data integrity, and achieve high data transmission efficiency and accurate data aggregation rate while consuming less energy to prolong network lifetime. To the best of our knowledge, this is the first work that provides both integrity and privacy based on homomorphic primitives. [ABSTRACT FROM AUTHOR]

The traditional Chinese medicine (TCM), which has thousands of years of clinical application among China and other Asian countries, is the pioneer of the "multicomponent-multitarget" and network pharmacology. Although there is no doubt of the efficacy, it is difficult to elucidate convincing underlying mechanism of TCM due to its complex composition and unclear pharmacology. The use of ligand-protein networks has been gaining significant value in the history of drug discovery while its application in TCM is still in its early stage. This paper firstly surveys TCM databases for virtual screening that have been greatly expanded in size and data diversity in recent years. On that basis, different screening methods and strategies for identifying active ingredients and targets of TCM are outlined based on the amount of network information available, both on sides of ligand bioactivity and the protein structures. Furthermore, applications of successful in silico target identification attempts are discussed in detail along with experiments in exploring the ligand-protein networks of TCM. Finally, it will be concluded that the prospective application of ligand-protein networks can be used not only to predict protein targets of a small molecule, but also to explore the mode of action of TCM. [ABSTRACT FROM AUTHOR]

ProOmpA is a preprotein that is translocated across the plasma membrane by the general secretory pathway in Escherichia coli. The molecular chaperon SecB in Sec pathway can recognize and bind proOmpA for its translocation. However, the structure of the SecB/proOmpA complex remains unknown. Here, we constructed an uncleavable proOmpA fused with metallothionein at its C-terminus and labeled it with metals in vitro for the study of cryo-electron microscopy. Using single particle cryo-electron microscopy, we reconstructed 3D structure of the stable SecB/proOmpA complex. The structure shows that the major portion of preprotein locates on one side of SecB tetramer, resulting in an asymmetric binding pattern. This work also provides a possible approach to the structure determination of small protein complexes by cryo-electron microscopy. [ABSTRACT FROM AUTHOR]

Small-diameter (<4 mm) vascular constructs are urgently needed for patients requiring replacement of their peripheral vessels. However, successful development of constructs remains a significant challenge. In this study, we successfully developed small-diameter vascular constructs with high patency using our integrally designed computer-controlled bioreactor system. This computer-controlled bioreactor system can confer physiological mechanical stimuli and fluid flow similar to physiological stimuli to the cultured grafts. The medium circulating system optimizes the culture conditions by maintaining fixed concentration of O2 and CO2 in the medium flow and constant delivery of nutrients and waste metabolites, as well as eliminates the complicated replacement of culture medium in traditional vascular tissue engineering. Biochemical and mechanical assay of newly developed grafts confirm the feasibility of the bioreactor system for small-diameter vascular engineering. Furthermore, the computer-controlled bioreactor is superior for cultured cell proliferation compared with the traditional non-computer- controlled bioreactor. Specifically, our novel bioreactor system may be a potential alternative for tissue engineering of large-scale small-diameter vascular vessels for clinical use. [ABSTRACT FROM AUTHOR]