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In this paper, a hybrid integrated broadband Doherty power amplifier (DPA) based on a multi-chip module (MCM), whose active devices are fabricated using the gallium nitride (GaN) process and whose passive circuits are fabricated using the gallium arsenide (GaAs) integrated passive device (IPD) process, is proposed for 5G massive multiple-input multiple-output (MIMO) application. An inverted DPA structure with a low-Q output network is proposed to achieve better bandwidth performance, and a single-driver architecture is adopted for a chip with high gain and small area. The proposed DPA has a bandwidth of 4.4–5.0 GHz that can achieve a saturation of more than 45.0 dBm. The gain compression from 37 dBm to saturation power is less than 4 dB, and the average power-added efficiency (PAE) is 36.3% with an 8.5 dB peak-to-average power ratio (PAPR) in 4.5–5.0 GHz. The measured adjacent channel power ratio (ACPR) is better than −50 dBc after digital predistortion (DPD), exhibiting satisfactory linearity.

Abstract The VIM (belonged to E3 ubiquitin ligase) gene family is crucial for plant growth, development, and stress responses, yet their role in salt stress remains unclear. We analyzed phylogenetic relationships, chromosomal localization, conserved motifs, gene structure, cis-acting elements, and gene expression patterns of the VIM gene family in four cotton varieties. Our findings reveal 29, 29, 17, and 14 members in Gossypium hirsutum (G.hirsutum), Gossypium barbadense (G.barbadense), Gossypium arboreum (G.arboreum), and Gossypium raimondii (G. raimondii), respectively, indicating the maturity and evolution of this gene family. motifs among GhVIMs genes were observed, along with the presence of stress-responsive, hormone-responsive, and growth-related elements in their promoter regions. Gene expression analysis showed varying patterns and tissue specificity of GhVIMs genes under abiotic stress. Silencing GhVIM28 via virus-induced gene silencing revealed its role as a salt-tolerant negative regulator. This work reveals a mechanism by which the VIM gene family in response to salt stress in cotton, identifying a potential negative regulator, GhVIM28, which could be targeted for enhancing salt tolerance in cotton. The objective of this study was to explore the evolutionary relationship of the VIM gene family and its potential function in salt stress tolerance, and provide important genetic resources for salt tolerance breeding of cotton.

In order to assess the reliability of electrical connector seals under storage environment, the failure analysis of 771 silicone seals for electrical connectors under storage environment determines that the failure mechanism of 771 silicone seals is mainly hydrolysis and oxidation of silicone matrix material. Based on the response surface design theory, the combination of temperature and humidity stress levels was determined, and the accelerated degradation test program of seals under combined temperature and humidity stress was constructed. Using the accelerated degradation test data, the degradation trajectory model of 771 silicone seals, the failure life distribution model, and the accelerated equation that characterizes the mathematical relationship between temperature and humidity and the life index of 771 silicone seals are established and validated at the statistical level, which realizes the reliability assessment of 771 silicone seals for electrical connectors in storage environments.

Male largemouth bass (Micropterus salmoides) are often overlooked because females grow faster. We explored the value of male largemouth bass by comparing muscle nutrition, texture, and transcriptomes between males and females. Females grew faster than males (p < 0.05) because of lipid accumulation. Male fish muscles had higher contents of serine, valine, methionine, arginine, nervonic acid, and α-linolenic acid (p < 0.05), and female fish muscles had higher contents of aspartic acid, glycine, cysteine, leucine, palmitic acid, docosahexaenoic acid, and 11,14,17-eicosatrienoic acid (p < 0.05). Male muscles had a higher concentration of collagen fibers and greater shear force, indicative of a chewier texture. Male muscles had a lighter color, suggesting that they were less susceptible to oxidation and deterioration. Transcriptomic analyses revealed upregulation of lpl, sadb, dgat2, bhmt, tecrb, and hsd3b7, encoding components of amino acid and fatty acid metabolism; and upregulation of akt2, src, and kras, encoding crucial regulators of cellular immunity and homeostasis, in male muscles. Immunity-related pathways, including apoptosis, ErbB signaling, and cellular senescence, were enriched in male fish muscles, indicating heightened immune function. The muscles of male fish have a unique profile and distinctive advantages in terms of nutrition, flavor, texture, and transcriptional regulation.

This study aimed to develop and validate a bone marrow edema model using a magnetic resonance imaging-based radiomics nomogram for the diagnosis of osteoarthritis. Clinical and magnetic resonance imaging (MRI) data of 302 patients with and without osteoarthritis were retrospectively collected from April 2022 to October 2023 at Longhua Hospital affiliated with the Shanghai University of Traditional Chinese Medicine. The participants were randomly divided into two groups (a training group, n = 211 and a testing group, n = 91). We used logistic regression to analyze clinical characteristics and established a clinical model. Radiomics signatures were developed by extracting radiomic features from the bone marrow edema area using MRI. A nomogram was developed based on the rad-score and clinical characteristics. The diagnostic performance of the three models was compared using the receiver operating characteristic curve and Delong’s test. The accuracy and clinical application value of the nomogram were evaluated using calibration curve and decision curve analysis. Clinical characteristics such as age, radiographic grading, Western Ontario and McMaster Universities Arthritis Index score, and radiological features were significantly correlated with the diagnosis of osteoarthritis. The Rad score was constructed from 11 radiological features. A clinical model was developed to diagnose osteoarthritis (training group: area under the curve [AUC], 0.819; testing group: AUC, 0.815). Radiomics models were used to effectively diagnose osteoarthritis (training group,: AUC, 0.901; testing group: AUC, 0.841). The nomogram model composed of Rad score and clinical characteristics had better diagnostic performance than a simple clinical model (training group: AUC, 0.906; testing group: AUC, 0.845; p < 0.01). Based on DCA, the nomogram model can provide better diagnostic performance in most cases. In conclusion, the MRI-bone marrow edema-based radiomics-clinical nomogram model showed good performance in diagnosing early osteoarthritis.

Abstract Background Largemouth bass (Micropterus salmoides) has significant economic value as a high-yielding fish species in China’s freshwater aquaculture industry. Determining the major genes related to growth traits and identifying molecular markers associated with these traits serve as the foundation for breeding strategies involving gene pyramiding. In this study, we screened restriction-site associated DNA sequencing (RAD-seq) data to identify single nucleotide polymorphism (SNP) loci potentially associated with extreme growth differences between fast-growth and slow-growth groups in the F1 generation of a largemouth bass population. Results We subsequently identified associations between these loci and specific candidate genes related to four key growth traits (body weight, body length, body height, and body thickness) based on SNP genotyping. In total, 4,196,486 high-quality SNPs were distributed across 23 chromosomes. Using a population-specific genotype frequency threshold of 0.7, we identified 30 potential SNPs associated with growth traits. Among the 30 SNPs, SNP19140160, SNP9639603, SNP9639605, and SNP23355498 showed significant associations; three of them (SNP9639603, SNP9639605, and SNP23355498) were significantly associated with one trait, body length, in the F1 generation, and one (SNP19140160) was significantly linked with four traits (body weight, height, length, and thickness) in the F1 generation. The markers SNP19140160 and SNP23355498 were located near two growth candidate genes, fam174b and ppip5k1b, respectively, and these candidate genes were closely linked with growth, development, and feeding. The average body weight of the group with four dominant genotypes at these SNP loci in the F1 generation population (703.86 g) was 19.63% higher than that of the group without dominant genotypes at these loci (588.36 g). Conclusions Thus, these four markers could be used to construct a population with dominant genotypes at loci related to fast growth. These findings demonstrate how markers can be used to identify genes related to fast growth, and will be useful for molecular marker-assisted selection in the breeding of high-quality largemouth bass.

Abstract Owing to the complexity of metros, the energy consumption characteristics of metro systems exhibit variability and the energy‐saving management of the systems encounters challenges. To encapsulate the essential characteristics of energy usage and to objectively assess the energy performance of metro systems, this study presents a generalized framework and applies it to a case study conducted in Tianjin. The study also employs correlation analysis to investigate the applicability of the indicators relevant to ridership. The results indicate that the monthly traction electricity consumption exhibits slight variation, while station electricity usage demonstrates substantial fluctuation with seasonal changes. For Tianjin Metro, the passenger factor hardly shows any effect on the electricity use of metro lines. The median value of traction electricity use is approximately 2.0 kWh/(car‐km) and that of the average annual station electricity use of underground lines ranges from 95 to 155 kWh/m2. The emission from the traction sector is 12.2 kgCO2/(vehicle‐km) and from the station sector is 118.6 kgCO2/m2. The study also identifies the energy‐intensive lines of the Tianjin Metro and compares the energy utilization among various global metro systems. The authors hope that this study can help shed light on the assessment of the energy status of metro systems and serve as a source of information for other City‐Metros to implement energy‐saving management.

The X-band medium distance microwave wireless power transmission (MWPT) system based on multilayer rectifier diode design is demonstrated in this paper. In order to pursuit highest rectification efficiency, the harmonic suppression rectifying circuit is proposed, which can acquire more than 60% rectification efficiency at the working frequency of 10 GHz. For the sake of longer distance, the Cassegrain antenna with an aperture of 1.6 m and the receiving planar array antenna with an area of 2 m × 2 m for the novel applications are designed. In the interest of improving the effective receiving area, the microwave rectifying antenna adopts the layered design of the receiving array antenna and the microwave rectifying circuit. Finally, this X-band medium distance MWPT system based on multilayer rectifier diode can achieve 400 W DC power with 10% RF-DC conversion efficiency for the distance of 70 m. The MWPT system can been applied in medium to long distance MWPT system, such as charging of various sensors, wireless power supplying and so on.

Abstract Cytokinin oxidase/dehydrogenase (CKX) is a key regulatory enzyme for the irreversible degradation of the plant hormone cytokinin (CK), which is important in growth and development and response to abiotic stresses in cotton. In this study, 27, 28, 14 and 14 CKXs were screened by FAD structural domain and cytokinin binding structural domain in Gossypium hirsutum, Gossypium barbadense, Gossypium arboreum and Gossypium raimondii, respectively. Their phylogenetic relationships and expression patterns were analyzed, and most GhCKXs were found to be tissue-specific and responsive to various abiotic stresses such as cold, heat, salt and PEG. GhCKX6b-Dt was selected for gene silencing in evolutionary branch II for salt stress, because its expression increased after salt stress in cotton plants. An increase in PRO and MDA content and a decrease in SOD activity due to this gene were found after inducing salt stress, contributing to oxidative damage and decreased salt tolerance. In this study, CKXs were analyzed to reveal the possible role of GhCKXs against abiotic stresses in cotton, which provides a basis for further understanding of the biological functions of CK in plants such as growth and development and stress resistance.

Abstract Background Inositol monophosphates (IMP) are key enzymes in the ascorbic acid (AsA) synthesis pathways, which play vital roles in regulating plant growth and development and stresses tolerance. To date, no comprehensive analysis of the expression profile of IMP genes and their functions under abiotic stress in cotton has been reported. Results In this study, the genetic characteristics, phylogenetic evolution, cis-acting elements and expression patterns of IMP gene family in cotton were systematically analyzed. A total of 28, 27, 13 and 13 IMP genes were identified in Gossypium hirsutum (G. hirsutum), Gossypium barbadense (G. barbadense), Gossypium arboreum (G. arboreum), and Gossypium raimondii (G. raimondii), respectively. Phylogenetic analysis showed that IMP family genes could cluster into 3 clades. Structure analysis of genes showed that GhIMP genes from the same subgroup had similar genetic structure and exon number. And most GhIMP family members contained hormone-related elements (abscisic acid response element, MeJA response element, gibberellin response element) and stress-related elements (low temperature response element, defense and stress response element, wound response element). After exogenous application of abscisic acid (ABA), some GhIMP genes containing ABA response elements positively responded to alkaline stress, indicating that ABA response elements played an important role in response to alkaline stress. qRT-PCR showed that most of GhIMP genes responded positively to alkaline stress, and GhIMP10D significantly upregulated under alkaline stress, with the highest up-regulated expression level. Virus-induced gene silencing (VIGS) experiment showed that compared with 156 plants, MDA content of pYL156:GhIMP10D plants increased significantly, while POD, SOD, chlorophyII and AsA content decreased significantly. Conclusions This study provides a thorough overview of the IMP gene family and presents a new perspective on the evolution of this gene family. In particular, some IMP genes may be involved in alkaline stress tolerance regulation, and GhIMP10D showed high expression levels in leaves, stems and roots under alkaline stress, and preliminary functional verification of GhIMP10D gene suggested that it may regulate tolerance to alkaline stress by regulating the activity of antioxidant enzymes and the content of AsA. This study contributes to the subsequent broader discussion of the structure and alkaline resistance of IMP genes in cotton.

The online prediction of power system dynamic frequency helps to guide the choice of control measures quickly and accurately after a disturbance, and this then ensures the reliable and stable operations of a power system. However, the prediction performance of the traditional single model is not accurate enough, and the prediction method cannot reflect the dynamic mechanism of the power system. To address these challenges, based on the analysis of the mechanism of the dynamic operation of a power system, a dynamic frequency online prediction method using the autoregressive integrated moving average (ARIMA) model and the deep belief network (DBN) is proposed in this paper. First, according to the mechanism of the dynamic operation of a power system, the dynamic frequency can be regarded as having two stages after the disturbance occurs. In the first stage, the frequency changes monotonously in the short term, which is predicted by the ARIMA model. Furthermore, the second stage is an oscillation phase with changing amplitude, which is predicted by the DBN. The calibration process is used to combine the two predicted results. Second, the three metrics including the frequency nadir (fnadir), the quasi-steady state frequency (fss), and the frequency curve obtained through the prediction are analyzed to measure the accuracy of the prediction results. Finally, to verify the accuracy of the proposed model, the IEEE 10-generator 39-bus benchmark system is used for verification.

Addressing the issue of increased shaft-system vibration in high-altitude mixed-flow hydropower generating units due to sand wear on turbine blades, a three-dimensional model of a specific mixed-flow water turbine was constructed. CFD numerical simulations were employed to analyze the fluid exciting force acting on the turbine runner under varying degrees of blade wear. An approximate analytical model was then established for the variation of fluid exciting force in the turbine runner system using the Fourier harmonic analysis method. A multi-degree-of-freedom mathematical model of flexural and inclined coupling vibration of a hydropower unit’s shafting, considering blade wear, was constructed. The nonlinear dynamic model was numerically calculated by the Runge–Kutta method. The vibration responses of the shafting of hydropower units under different wear degrees were obtained by means of a time-domain diagram, frequency-domain diagram, axis-locus diagram, phase-locus diagram, and Poincare mapping. Based on the formula for calculating the wear amount of the blade material, the runner amplitude degradation trajectory model was established, and the pseudo-failure time of turbine blades was determined according to the allowable value of amplitude.

A-galactosidases (AGALs), the oligosaccharide (RFO) catabolic genes of the raffinose family, play crucial roles in plant growth and development and in adversity stress. They can break down the non-reducing terminal galactose residues of glycolipids and sugar chains. In this study, the whole genome of AGALs was analyzed. Bioinformatics analysis was conducted to analyze members of the AGAL family in Gossypium hirsutum, Gossypium arboreum, Gossypium barbadense, and Gossypium raimondii. Meanwhile, RT-qPCR was carried out to analyze the expression patterns of AGAL family members in different tissues of terrestrial cotton. It was found that a series of environmental factors stimulated the expression of the GhAGAL3 gene. The function of GhAGAL3 was verified through virus-induced gene silencing (VIGS). As a result, GhAGAL3 gene silencing resulted in milder wilting of seedlings than the controls, and a significant increase in the raffinose content in cotton, indicating that GhAGAL3 responded to NaCl stress. The increase in raffinose content improved the tolerance of cotton. Findings in this study lay an important foundation for further research on the role of the GhAGAL3 gene family in the molecular mechanism of abiotic stress resistance in cotton.

[Objective] The rural revitalization performance evaluation index system was constructed based on five dimensions: thriving businesses, pleasant living environments, social etiquette and civility, effective governance, and prosperity, in order to provide references for comprehensive evaluation of rural revitalization performance. [Methods] Rural revitalization performance in Fujian Province was evaluated by applying the entire-array-polygon synthesis illustration model from 2011—2020. [Results] The thriving businesses index for the 12th Five-Year Plan period was better than that of the 13th Five-Year Plan period (p0.05). Performance indexes for pleasant living environments, effective governance, and prosperity for the 13th Five-Year Plan period were at a high level, and the performance level was better than that of the 12th Five-Year Plan period (p 2019 > 2018 > 2015 > 2016 > 2017 < 2014 > 2013 > 2012 > 2011. Rural revitalization performance in Fujian Province was relatively higher from 2018 to 2020. In the process of promoting rural revitalization strategy, people should refine the performance evaluation index system and construct a rural revitalization performance evaluation system based on the actual situation of each city.

Cysteine, an early sulfur-containing compound in plants, is of significant importance in sulfur metabolism. CYS encodes cysteine synthetase that further catalyzes cysteine synthesis. In this investigation, CYS genes, identified from genome-wide analysis of Gossypium hirsutum bioinformatically, led to the discovery of GhCYS2 as the pivotal gene responsible for Cd2+ response. The silencing of GhCYS2 through virus-induced gene silencing (VIGS) rendered plants highly susceptible to Cd2+ stress. Silencing GhCYS2 in plants resulted in diminished levels of cysteine and glutathione while leading to the accumulation of MDA and ROS within cells, thereby impeding the regular process of photosynthesis. Consequently, the stomatal aperture of leaves decreased, epidermal cells underwent distortion and deformation, intercellular connections are dramatically disrupted, and fissures manifested between cells. Ultimately, these detrimental effected culminating in plant wilting and a substantial reduction in biomass. The association established between Cd2+ and cysteine in this investigation offered a valuable reference point for further inquiry into the functional and regulatory mechanisms of cysteine synthesis genes.

The elevator door system plays a crucial role in ensuring elevator safety. Fault prediction is an invaluable tool for accident prevention. By analyzing the sound signals generated during operation, such as component wear and tear, the fault of the system can be accurately determined. This study proposes a GNN-LSTM-BDANN deep learning model to account for variations in elevator operating environments and sound signal acquisition methods. The proposed model utilizes the historical sound data from other elevators to predict the remaining useful life (RUL) of the target elevator door system. Firstly, the opening and closing sounds of other elevators is collected, followed by the extraction of relevant sound signal characteristics including A-weighted sound pressure level, loudness, sharpness, and roughness. These features are then transformed into graph data with geometric structure representation. Subsequently, the Graph Neural Networks (GNN) and long short-term memory networks (LSTM) are employed to extract deeper features from the data. Finally, transfer learning based on the improved Bhattacharyya Distance domain adversarial neural network (BDANN) is utilized to transfer knowledge learned from historical sound data of other elevators to predict RUL for the target elevator door system effectively. Experimental results demonstrate that the proposed method can successfully predict potential failure timeframes for different elevator door systems.

In addressing the design challenges for constant-stress accelerated life testing in non-rectangular experimental domains, we aim to optimize the precision in estimating parameters for the product reliability statistical model. Following the principles of regression orthogonal design theory to determine the combinations of stress levels, we constrain the maximum stress levels of each experimental stress along the boundary curve of the non-rectangular experimental domain. The remaining stress levels and the allocation ratios of specimens for each test serve as design variables in the optimization process. We establish a mathematical model for the optimal design of constant-stress accelerated life testing in non-rectangular experimental domains. The results of the optimized design for comprehensive stress accelerated life testing in non-rectangular experimental regions of aerospace electrical connectors indicate that, with the same sample size, the optimized testing scheme not only enhances the precision of model parameter estimation but also reduces the number of required tests. At an equivalent number of tests and testing duration, the optimization scheme proposed in this study demonstrates an improvement of over 63% in the precision of model parameter estimation compared to the EM-optimized testing scheme in non-rectangular experimental regions. Using the mean, standard deviation, and coefficient of variation of the determinant values of the information matrix as criteria for evaluating the precision and robustness of experimental designs, a simulated evaluation was conducted for the optimized experimental design, a conventional experimental design, and an EM experimental design. The results indicate that the optimal experimental design outperforms both the conventional experimental design and the EM experimental design in terms of precision and robustness.

Quantification methods of river basin ecological compensation with a scientific basis are not only a research hotspot in the field of resources and environment, but also an urgent technical difficulty needing to be solved in environmental management. The theory of property rights and externalities provides us with a new method to understand ecological compensation, which helps us to put forward a clear policy path to effectively solve the problem of ‘the tragedgy of the Commons’ in the ecological environment protection of river basins. Based on the externality problems of social and economic activities for a river basin, a standard calculation method under the combined scenario of ‘clear property rights, water quality and quantity, and opportunity cost’ was built in this paper. Taking the Minjiang River basin as an example, the definition of ecological property rights of the basin was divided into three scenarios: ‘upstream has pollution rights’, ‘upstream has no pollution rights’ and ‘upstream and downstream co-construction and sharing’. Ecological compensation standards of the Minjiang River basin under different property rights from 2015 to 2019 were calculated. The results showed that: (i) in the case where the upstream has pollution rights, the ecological compensation amount of Sanming City ranged from 2.41–9.36 × 108 Yuan, the final compensation value of Nanping City was 2.29–18.99 × 108 Yuan, and the ecological compensation cost of Fuzhou City was 6.78–28.35 × 108 Yuan; (ii) if the upstream area has no pollution rights, the compensation values of Sanming City and Nanping City to the downstream area were each 0; and (iii) under the case of upstream and downstream co-construction and sharing, the ecological compensation value of Sanming City was 6.25–21.34 × 108 Yuan, the final compensation value of Nanping City was 5.80–20.38 × 108 Yuan, and Fuzhou City needed to pay 12.05–36.38 × 108 Yuan for eco-compensation. The calculated results of ecological compensation standards in the Minjiang River basin indicated the amount of ecological compensation paid by the downstream to the upstream showing an upward trend on the whole. This method was relatively easy to define property rights and obtain data, taking into account the benefits of upstream and downstream, and the calculation process was relatively simple, which developed and supplemented the traditional ecological compensation method used for river basins. HIGHLIGHTS The empirical method combined clear property rights, water quality and quantity, and opportunity cost.; Determines the proportion according to the water sharing coefficient.; Calculates the total cost by superimposing the opportunity cost.; Both a temporal and spatial analysis of the values of ecological compensation are served.; Expands research into environmental economic policy and ecological compensation.;

Multi-aperture electrical connectors are widely used in the aerospace system to provide high-reliability and high-quality connections. The existing reliability assessment methods only focus on the single-aperture electrical connectors, and ignored the influence of the aperture difference on the reliability of electrical connectors, which may lead to errors in the evaluation results. In order to assess the contact reliability of multi-aperture electrical connectors at storage environment, this paper build a mathematical relationship between structure parameter of contact pairs and contact force by analyzing the slotted leaf spring jack reed structure of the contact pair and using the cantilever beam model. Based on the growth law of the oxide layer on the surface of the contact pair, the degradation trajectory model of the contact pair performance was set up which incorporating the structure parameters of contact pairs, such as pin diameter, reed length, radius of curvature of the inner and outer surfaces, and the acceleration model was established by combining the Arrhenius equation. Then based on the established degradation trajectory model, the degradation failure distribution model of contact pairs was derived, and the contact reliability evaluation model of multi-aperture electrical connectors was established by using the weakest ring model. The test scheme of constant stress accelerated degradation of electrical connectors was formulated and carried out. Finally, this paper verified the correctness of the model through analyzing the test data, and obtained the reliable life of multi-aperture electrical connectors under the storage environment temperature, which realized the contact reliability assessment of multi-aperture electrical connectors.

Covalent inhibitors targeting the main protease (Mpro, or 3CLpro) of SARS-CoV-2 have shown promise in preclinical investigations. Herein, we report the discovery of two new series of molecules that irreversibly bind to SARS-CoV-2 Mpro. These acrylamide containing molecules were discovered using our covalent DNA-encoded library (DEL) screening platform. Following selection against SARS-CoV-2 Mpro, off-DNA compounds were synthesized and investigated to determine their inhibitory effects, the nature of their binding, and to generate preliminary structure-activity relationships. LC-MS analysis indicates a 1:1 (covalent) binding stoichiometry between our hit molecules and SARS-CoV-2 Mpro. Fluorescent staining assay for covalent binding in the presence of cell lysate suggests reasonable selectivity for SARS-CoV-2 Mpro. And lastly, inhibition of enzymatic activity was also observed against a panel of 3CLpro enzymes from different coronavirus strains, with IC50 values ranging from inactive to single digit micromolar. Our results indicate that DEL selection is a useful approach for identifying covalent inhibitors of cysteine proteases.

PurposeThis study aimed to use meta-analysis to determine the impact of resistance and balance training on athletic ability and quality of life for patients with osteoporotic vertebral fracture (OVF).MethodsThis study followed the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) criteria for systematic reviews and meta-analyzes. The PubMed, Web of science, Cochrane, Embase, and CNKI databases were searched for randomized controlled trials (RCTs) up to September 2022. The search strategy was related to the intervention measures, population, and results, and was structured around the search terms: “Exercise,” “Osteoporotic vertebral fracture,” and “activities of function.” Two reviewers strictly implemented the inclusion and exclusion criteria. Subgroup analyzes of age and training duration were performed for the main outcomes.ResultsWe included 12 RCTs (n = 1,289) of resistance and balance training in patients with OVF. Compared with controls, the intervention group showed improvements on the Quality of Life Questionnaire issued by the European Foundation for Osteoporosis, visual analog pain scale, Timed Up and Go, falls efficacy scale international (FES-I), kyphosis, and functional reach. On subgroup analysis, the effect was more significant when training continued >10 weeks.ConclusionResistance and balance exercise training improved function and balance, and reduced fall risk in patients with OVF. We recommend resistance and balance training for at least 10 weeks. Future multicenter, large sample trials are needed for more reliable conclusions.

This paper demonstrates the analysis of a long-distance high-power microwave wireless power transmission (MWPT) system based on asymmetrical resonant magnetron and cyclotron-wave rectifier. In the system, the novel magnetron with the asymmetrical resonant cavity, the straps, and the output loop coupling circuit can effectively promote the beam–wave interaction, suppress the mode competition, and enhance the output coupling, which results in a 400 kW output microwave power with a conversion efficiency of 45%. The transceiver Cassegrain antenna system with its simple structure, high conversion efficiency, and high power capacity can attain an integral power transmission efficiency of 2.6% at 10 km distance. The cyclotron-wave rectifier with high efficiency and single-tube high power capacity can achieve 85% microwave to DC conversion efficiency. Finally, the long-distance high-power MWPT system can achieve 8.5 kW DC power with about 1% DC–DC transmission efficiency at the operating 2.45 GHz frequency and for the 10 km distance. Such a system is likely a potential and attracting solution to remotely power the fuel-free aerial vehicle from the ground, can also provide electrical power to an isolated mountain top or an island, and even an alternative to transmit the power from space solar power satellite in geostationary orbit to the ground.

Electro-hydrostatic actuator (EHA), as an emerging power-by-wire (PBW) actuation mechanism with high energy efficiency and fast responsiveness, has been widely used in modern flight control systems. As a pivotal component, the fault diagnosis of EHA is necessary to ensure the reliability of the aircraft. Although researchers have proposed many effective fault diagnosis techniques at present, most of them can only deal with single-factor faults effectively. Recent studies on multi-state reliability and competing failure show that complicated systems such as EHA are more prone to multi-factor failures than single-factor failures. Therefore, an improved EKF based on excitation equivalent conversion is proposed in this paper to achieve the multi-factor fault diagnosis of EHA. First, the existing fault diagnosis methods for EHA and their limitations in multi-factor fault diagnosis are discussed. Then, multi-parameters estimation and observability, the key issues to achieve multi-factor fault diagnosis, are analyzed. Based on the structural characteristics and observability analysis of the second-order system, excitation equivalent conversion is introduced to establish additional available equation about the unknown state parameters to realize the multi-parameter estimation when system is unobservable. Finally, simulation and prototype test experiments have been performed, and the results demonstrate the efficacy of the proposed method, which outperforms that of the traditional single-factor failure analysis methods by comparison.

Microwave-absorbing materials have attracted extensive attention due to the development of electronic countermeasures. In this study, novel nanocomposites with core–shell structures based on the core of Fe-Co nanocrystals and the shell of furan methylamine (FMA)-modified anthracite coal (Coal-F) were designed and fabricated. The Diels-Alder (D-A) reaction of Coal-F with FMA creates a large amount of aromatic lamellar structure. After the high-temperature treatment, the modified anthracite with a high degree of graphitization showed an excellent dielectric loss, and the addition of Fe and Co effectively enhanced the magnetic loss of the obtained nanocomposites. In addition, the obtained micro-morphologies proved the core–shell structure, which plays a significant role in strengthening the interface polarization. As a result, the combined effect of the multiple loss mechanism promoted a remarkable improvement in the absorption of incident electromagnetic waves. The carbonization temperatures were specifically studied through a setting control experiment, and 1200 °C was proved to be the optimum parameter to obtain the best dielectric loss and magnetic loss of the sample. The detecting results show that the 10 wt.% CFC-1200/paraffin wax sample with a thickness of 5 mm achieves a minimum reflection loss of −41.6 dB at a frequency of 6.25 GHz, indicating an excellent microwave absorption performance.

Yeasts are one of the predominant microbial groups in fermented meats. In this study, yeast communities of Chinese Dong fermented pork (Nanx Wudl) were investigated and the technological properties of 73 yeast isolates were evaluated. Through culture-dependent and high-throughput sequencing methods, the main yeast species identified included Pichia membranifaciens, Kazachstania bulderi, Millerozyma farinosa, Candida zeylanoides, Kazachstania exigua, Candida parapsilosis and Saccharomyces cerevisiae. Among these yeasts, P. membranifaciens, M. farinosa, K. exigua and K. bulderi were detected in fermented meats for the first time. A total of 73 yeast isolates was investigated for their lipolytic and proteolytic activities. All yeast species showed lipolytic activity, while proteolytic activity against meat protein was only detected in S. cerevisiae. Assay of aroma-producing potential was performed in a model simulating fermented sausage condition. Inoculation of yeast strains increased volatiles production, especially esters and alcohols. The highest ester production was observed in S. cerevisiae Y70 strain, followed by K. exigua Y12 and K. bulderi Y19. C. zeylanoides Y10 and S. cerevisiae Y70 were the highest producers of benzeneethanol and 3-methyl-1-butanol. S. cerevisiae Y70 with its highest production of branched alcohols and esters could be a promising candidate as aroma enhancer in the manufacture of fermented sausages.

This paper presents a new design methodology for broadband Doherty architecture using the three-port input and output networks technique. The proposed topology was developed to overcome the Doherty power amplifier (DPA) bandwidth limitations. The output three-port network performs the impedance matching from any load impedance to the optimum loads for both main and peaking transistors and also combines the power delivered from the two devices at any power ratio. On the other hand, the input-splitting network is proposed for matching the input impedances of the two transistors to the source impedance. The freedom in choosing the power division ratio of the input network enables us to achieve a tradeoff between efficiency and linearity. Also, it provides a way to accomplish the phase compensation using an arbitrary phase difference between the two branches of the Doherty power amplifier and thus, helps obviate the need of the highly bandwidth limiting offset lines found in the Doherty design. A two-stage broadband Doherty power amplifier is implemented using 0.25-um GaN HEMT MMIC process to validate the proposed topology. The fabricated DPA was measured under both continuous wave (CW) and modulated signal at different operating frequencies. Across 3.3-3.7 GHz, the implemented DPA delivers a maximum output power exceeding 42 dBm, power added efficiency (PAE) over 52 % at the peak power and over 38 % in the back-off state over the operating 400 MHz bandwidth. The fully integrated circuit has a chip-size of 4.4 mm × 3.5 mm.

The effect of a proteolytic starter culture isolated from Nanx Wudl, on microbiological, biochemical and organoleptic attributes of dry fermented sausages was investigated during processing. Based on preliminary screening, the combination of Staphylococcus xylosus SX16 and Lactobacillus plantarum CMRC6, showing excellent proteolytic activity in vitro, was selected as the multi-strain starter (starter LS). For comparison, the single-strain starter culture of L. plantarum CMRC6 (starter LB) and non-inoculated control were also tested. During fermentation, lactic acid bacteria and staphylococci dominated the microbiota and suppressed the Enterobacteriaceae growth in LS-inoculated sausages. The addition of LS starter accelerated acidification and proteolysis during ripening, improving the contents of total free amino acids and several essential free amino acids (Phe, Ile and Leu). Volatile compounds analysis revealed that LS-fermented sausage showed the highest abundance of 3-methyl-1-butanol, probably due to the inoculated S. xylosus. The inoculation of LS starter improved the sensory properties of sausages, especially the flavor attribute. Therefore, S. xylosus SX16 and L. plantarum CMRC6 are promising candidates for inclusion as multi-strain starters in the manufacture of gourmet fermented dry sausage.

The effect of sodium chloride (NaCl) curing salt content on protein oxidation, lipid oxidation and lipolysis of Chinese dry sausage was investigated. Two groups Chinese dry sausages with 2% and 4% (m/m) salt content were studied. The degree of protein oxidation increased during the processes in two groups sausages, while the content of phospholipids decreased, neutral lipids and free fatty acids increased. The degree of protein oxidation, lipid oxidation and lipolysis in 4% NaCl content group was higher than those in 2% NaCl content group, while 4% NaCl content group has higher lipase activity. In conclusion, 4% NaCl may facilitate the protein oxidation, lipid hydrolysis and oxidation in Chinese dry sausage, and the protein oxidation had strong correlation with lipid oxidation and lipolysis. The results could provide a basis for improving the technology of industrial production.

To provide references for safe and effective implementing rehabilitation treatment during hospitalization, in this article, we exploratively discusses the principle and strategy of treatment for inpatients with COVID-19 based on clinical characteristics as infectious pulmonary diseases. The foundation of rehabilitation intervention in COVID-19 is'integration of prevention, treatment and rehabilitation'frame. The earlier the rehabilitation intervention starts, the better the prognosis will be, in the stable stage of the disease. Anoxia is the main clinical manifestation for inpatients with COVID-19. The best intervention point for inpatient's rehabilitation may be resolving the disease-caused anoxia via systemic management approaches safely and efficiently in rehabilitation medicine. Thus, this article proposes that we should keep on the principle, 'No Excess, No Absence', and use the strategy basing on'Energy Conservation and Emission Reduction'as common goal management in the cooperation of multidisciplinary team approach on inpatient of COVID-19 rehabilitation. The series of stabilization, relaxation and energy-saving on'physical-mental level'were the major methods. And meanwhile the interaction among evaluation and intervention on individual and environment at the same time with the inclusion of COVID-19 prevention and control will rule into rehabilitation management process. The rehabilitation intervention on COVID-19 inpatients is not only the technique-oriented but also a systemic management process. The option of health efficacy promotion approaches via systemic vision is the demonstration of the most important concept in rehabilitation medicine, 'People Frist of All'. The cognition on various meaning in rehabilitation medicine will provide new for rehabilitation field.

Ceiling-fan-integrated air-conditioning (CFIAC) is a concept in which terminal supply ducts and diffusers are replaced by vents/nozzles that jet supply air into the vicinity of ceiling fans to be mixed and distributed within the room. CFIAC distributes the supply air within the room and convectively cools the occupants. This could allow raised thermostat set-points and reduced energy for the air-conditioning system’s supply fan and compressor. Previous work on CFIAC shows that the air temperature in the occupied zone is spatially uniform, but the air speed is not. This paper evaluates the thermal comfort performance of a CFIAC system under various ambient temperatures and fan operation modes. Human subject experiments and thermal manikin tests were conducted to characterize how subjects evaluate the thermal comfort performance across the room’s floorplate, and how CFIAC affects human body heat transfer. Despite the spatial variation in air speed across the floorplate, CFIAC created uniform thermal comfort perceptions. Comfort at 28°C was similar to that of 26°C for the overhead supply neutral reference condition. Human subjects preferred having the increased air movement over that of the reference condition. The paper evaluates thermal comfort indexes appropriate for evaluating and designing CFIAC. 'Practice relevance' Despite the spatial variation in air speed across the floorplate, CFIAC created quite uniform thermal comfort perceptions. Conventional air-conditioning systems often create overcooling complaints because supply volumes through diffusers are kept overly high in order to disperse cold temperature dumping in the space. Ceiling fan circulation provides sufficient dispersion to eliminate this issue. However, it is important for standards writers and designers to understand that the room temperatures should not be so cold that the highest airspeeds caused by the ceiling fans will be uncomfortable for the occupants in the fan-cooling zone. To evaluate CFIAC systems, the standard effective temperature (SET) model is shown to be useful and the elevated air speed method in American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 55 also provides appropriate design guidance.

Considering the deep foundation pit of a car dumper room close to the Beijing–Baotou railway, the countermeasures of the foundation pit design are analyzed according to the surrounding environment and stratum conditions. Through Midas GTS software as well as field measured results, the construction effect on the adjacent railway subgrade is discussed. Therefore, the deformation characteristics of the foundation pit as well as the retaining structure, including the railway subgrade, caused by the excavation process, are revealed. The results show that the five-sided water-stop structure formed by cement piles around and at the bottom of the pit avoids the consolidation settlement of the adjacent railway subgrade caused by deep dewatering and also reduces the lateral displacement (i.e., in a horizontal direction) and the heave of the pit bottom. As a result, the lateral displacement near the railway side is larger than that of the retaining structure on the other side due to the subgrade on the pit side. The cross-lot bracing across the foundation pit will transfer the bias pressure of the subgrade to the retaining structure far away from the railway, while the transfer effect of the knee bracing is not obvious. The deformation of the railway subgrade and its evolution rate caused by the removal of internal bracing is significantly greater than the subgrade deformation and the change rate of deformation caused by excavation. The research results provide useful guidance for the deep foundation pit design.

We aimed to explore whether motor function and activities of daily life (ADL) could be improved with the application of visual deprivation in two patients with Pusher syndrome complicated by hemispatial neglect after right basal ganglia stroke. We assessed two stroke patients suffering from severe motor disturbances, both tilting heavily to the left, with diagnoses of Pusher syndrome and left hemispatial neglect. Vision in the left eye was deprived using patches during clinical rehabilitation. Motor function promotion was confirmed using the Burke Lateropulsion Scale (BLS), Fugl–Meyer Balance Scale (FMBS), and Holden grade (HG), while the Barthel index (BI) assessed ADL immediately and 1 week after intervention. Both patients regained standing balance immediately using visual deprivation, as well as walking ability, although both scored 0 on the FMBS and HG. After 1 week of treatment, one patient increased to 11 and 3 on the FMBS and HG, respectively, while the BLS score decreased from 12 to 2, and the ADL increased from 23 to 70. The other patient demonstrated increases to 10 and 3 on the FMBS and HG, respectively, with the BLS decreasing from 13 to 3, and the ADL increasing from 25 to 60. Therefore, in the rehabilitation treatment of Pusher syndrome complicated by hemispatial neglect due to basal ganglia stroke, visual deprivation can significantly improve motor function and shorten the treatment course.

Dendrobium officinale, a well-known plant used as a medicinal and food homologous product, has been reported to contain various bioactive components, such as polysaccharides, bibenzyls, phenanthrenes, and flavonoids. It is also widely used as a traditional medicine to strengthen “Yin”, nourish heart, tonify five viscera, remove arthralgia, relieve fatigue, thicken stomach, lighten body, and prolong life span. These traditional applications are in consistent with modern pharmacological studies, which have demonstrated that D. officinale exhibits various biological functions, such as cardioprotective, anti-tumor, gastrointestinal protective, anti-diabetes, immunomodulatory, anti-aging, and anti-osteoporosis effects. In this review, we summarize the research progress of D. officinale from November 2016 to May 2021 and aim to better understand the botany, traditional use, phytochemistry, and pharmacology of D. officinale, as well as its quality control and safety. This work presents the development status of D. officinale, analyzes gaps in the current research on D. officinale, and raises the corresponding solutions to provide references and potential directions for further studies of D. officinale.

Embelin is a naturally occurring para-benzoquinone isolated from Embelia ribes (Burm. f.) of the Myrsinaceae family. It was first discovered to have potent inhibitory activity (IC50 = 4.2 μM) against α-glucosidase in this study. Then, four series of novel embelin derivatives were designed, prepared and evaluated in α-glucosidase inhibition assays. The results show that most of the embelin derivatives synthesised are effective α-glucosidase inhibitors, with IC50 values at the micromolar level, especially 10d, 12d, and 15d, the IC50 values of which are 1.8, 3.3, and 3.6 μM, respectively. Structure–activity relationship (SAR) studies suggest that hydroxyl groups in the 2/5-position of para-benzoquinone are very important, and long-chain substituents in the 3-position are highly preferred. Moreover, the inhibition mechanism and kinetics studies reveal that all of 10d, 12d, 15d, and embelin are reversible and mixed-type inhibitors. Furthermore, docking experiments were carried out to study the interactions between 10d and 15d with α-glucosidase.

In this work, the properties of a two-tone signal driven concurrent power amplifier (CPA) are analyzed extensively. Firstly, the characteristics of two-tone signals are discussed to explain the nonlinearity and efficiency of two-tone signal driven CPA. Secondly, a method of how to solve the efficiency of a two-tone signal driven CPA is proposed in this paper with a detailed calculation procedure and complete theory. Finally, a general empirical expression to calculate the drain efficiency (DE) of CPA versus the frequency ratio and the amplitude ratio of the two carriers is proposed. Simulation results and experimental verifications are given to validate the proposed analytical formulation to predict the efficiency of CPAs when driven with balanced or imbalanced two-tone signals.

Abstract Sharp corners usually are used on glass contours to meet the highly increasing demand for personalized products, but they result in a broken wheel center toolpath in edge grinding. To ensure that the whole wheel center toolpath is of G1 continuity and that the grinding depth is controllable at the corners, a transition toolpath generation method based on a velocity-blending algorithm is proposed. Taking the grinding depth into consideration, the sharp-corner grinding process is planned, and a velocity-blending algorithm is introduced. With the constraints, such as traverse displacement and grinding depth, the sharp-corner transition toolpath is generated with a three-phase motion arrangement and with confirmations of the acceleration/deceleration positions. A piece of glass with three sharp corners is ground on a three-axis numerical-control glass grinding equipment. The experimental results demonstrate that the proposed algorithm can protect the sharp corners from breakage efficiently and achieve satisfactory shape accuracy. This research proposed a toolpath generation method based on a velocity-blending algorithm for the manufacturing of personalized glass products, which generates the transition toolpath as needed around a sharp corner in real time.

Introduction This study investigated the relationships between differentially co-expressed gene pairs or links (DCLs) and transcription factors (TFs) in the gene transcription regulatory network (GTRN) to clarify the molecular mechanisms underlying the pathogenesis of Parkinson’s disease (PD). Material and methods Microarray dataset GSE7621 from Gene Expression Omnibus (GEO) was used to identify differentially expressed genes (DEGs) and perform Gene Ontology (GO) enrichment analysis. Differentially co-expressed genes (DCGs) and DCLs were identified by the DCGL package in R soft-ware. DCLs that were potentially related to the regulation mechanisms, and corresponding TFs, were identified using the DR sort function in the DCGL V2.0 package. The GTRN was constructed with these DCLs-TFs, and visualized with Cytoscape software. Results A total of 131 DEGs, including 77 up-regulated DEGs and 54 down-regulated DEGs, were identified, which were mainly enriched for plasma membrane, cell activities, and metabolism. We found that ICAM1-LTBP and CTHRC1-UTP3 might alter gene regulation relationships in PD. The GTRN was constructed with DCLs-TFs, including 348 nodes (118 TFs and 230 DCGs) and 1045 DCLs. These TFs (AHR, SP1, PAX5, etc.) could regulate many target genes (e.g. ICAM1 and LTBP) in the GTRN of PD. Conclusions ICAM1 and LTBP may play a role in PD symptom development and pathology, and might be regulated by important TFs (AHR, SP1, PAX5, etc.) identified in the GTRN of PD. These findings may help elucidate the molecular mechanisms underlying PD and find a novel drug target for this disease.

Objective: To compare the efficacy of kinesio taping on chronic non-specific low back pain with that of other general physical therapies. Methods: Relevant studies published up to 31 July 2018 were searched in electronic databases (PubMed, Web of Science, Science Direct, Physiotherapy Evidence Database (PEDro), Cochrane Library, Wanfang Data, Vip Data and China National Knowledge Infrastructure). The quality of included studies was assessed using a risk of bias assessment tool, as recommended by the Cochrane Collaboration. Data from visual analogue scales and Oswestry Disability Index were extracted as selected outcome indicators. Tests of heterogeneity were performed. Weight-ed mean difference (WMD) data with its 95% confidence intervals (95% CI) were used as a measure of effect sizes, in order to pool the results from each included study using either a fixed or random effects model (where appropriate and possible). Results: Eight studies fulfilled the inclusion and exclusion criteria. The quality of included studies was moderate. Patients with chronic non-specific low back pain in the kinesio taping group achieved better pain relief (WMD = –1.22; 95% CI –1.49 to –0.96, I2 = 91%, p

Abstract The vibration propagates through the shaft in the form of elastic waves. The propagation characteristics of the elastic waves are affected by the axial loads. The influence of the axial loads to the propagation characteristics of the elastic waves is studied in this paper. Firstly, the transfer matrix of the elastic waves for the non-uniform shaft with axial loads is deduced by combining the transfer matrix without axial load and the additional equation caused by the axial load. And then, a numerical method is used to study the influence of the axial load, non-uniformity and the rotating speed to the propagation characteristics of the elastic waves. It’s found that a new Stop Band will appear due to the axial force, and the central frequency of which will decrease as the increase of the force, while the band width of which remains the same. The central frequency of the new Stop Band will also increase as the increase of the cross-section area ratio; however, the rotating speed of the shaft doesn’t affect the propagation characteristics of the elastic waves obviously. Finally, an experimental rig is built up for further study, even though there are some small local errors, the results of experiments match well with the numerical ones, which indicates the validation of the theoretical results. The result can help to study the influence of the axial load to the dynamics of a non-uniform shaft and help to reveal the vibration propagating mechanism in such a shaft.

In order to study the influence of the random perturbation of time-varying mesh stiffness on the dynamics of the helical gearing system, based on Newton's law, a stochastic dynamics model of a six-degree-of-freedom helical gear system is established and dimensionless processing is carried out. Combining the bifurcation diagram, Poincaré map, Lyapunov exponent diagram, phase diagram, and time history diagram of system, the bifurcation characteristics of the helical gear system with considering the random perturbation of mesh stiffness are analyzed. Numerical simulation analysis results show, when the time-varying mesh stiffness of helical gears increases, the helical gear transmission system gradually shifts from periodic motion to chaotic motion by doubling bifurcation. The increase of random disturbance makes the system’s bifurcation characteristics change, and enters chaos in advance, the dynamics characteristics of the system have an essential influence. Therefore, reasonable parameters should be selected during design to ensure system stability.

Plants benefit extensively from endophytic bacteria, which live in host plant tissues exerting no harmful effects. Bacterial endophytes promote the growth of host plants and enhance their resistance toward various pathogens and environmental stresses. They can also regulate the synthesis of secondary metabolites with significant medicinal properties and produce various biological effects. This review summarizes recent studies on the relationships between bacterial endophytes and medicinal plants. Endophytic bacteria have numerous applications in agriculture, medicine, and other industries: improving plant growth, promoting resistance toward both biotic and abiotic stresses, and producing metabolites with medicinal potential. Their distribution and population structure are affected by their host plant’s genetic characteristics and health and by the ecology of the surrounding environment. Understanding bacterial endophytes can help us use them more effectively and apply them to medicinal plants to improve yield and quality.

Objectives To develop a model of in-hospital mortality using medical record front page (MRFP) data and assess its validity in case-mix standardisation by comparison with a model developed using the complete medical record data.Design A nationally representative retrospective study.Setting Representative hospitals in China, covering 161 hospitals in modelling cohort and 156 hospitals in validation cohort.Participants Representative patients admitted for acute myocardial infarction. 8370 patients in modelling cohort and 9704 patients in validation cohort.Primary outcome measures In-hospital mortality, which was defined explicitly as death that occurred during hospitalisation, and the hospital-level risk standardised mortality rate (RSMR).Results A total of 14 variables were included in the model predicting in-hospital mortality based on MRFP data, with the area under receiver operating characteristic curve of 0.78 among modelling cohort and 0.79 among validation cohort. The median of absolute difference between the hospital RSMR predicted by hierarchical generalised linear models established based on MRFP data and complete medical record data, which was built as ‘reference model’, was 0.08% (10th and 90th percentiles: −1.8% and 1.6%). In the regression model comparing the RSMR between two models, the slope and intercept of the regression equation is 0.90 and 0.007 in modelling cohort, while 0.85 and 0.010 in validation cohort, which indicated that the evaluation capability from two models were very similar.Conclusions The models based on MRFP data showed good discrimination and calibration capability, as well as similar risk prediction effect in comparison with the model based on complete medical record data, which proved that MRFP data could be suitable for risk adjustment in hospital performance measurement.

In the current research, we propose a novel non-ordinary state-based peridynamics (PD) fatigue model for multiple cracks’ initiation and growth under tension–tension fatigue load. In each loading cycle, the fatigue loading is redistributed throughout the peridynamic solid body, leading to progressive fatigue damage formation and expansion in an autonomous fashion. The proposed fatigue model parameters are first verified by a 3D numerical solution, and then, the novel model is used to depict the widespread fatigue damage evolution of the aircraft wing corner box. The modified constitutive damage model has been implemented into the peridynamic framework. Furthermore, the criteria and processes from multiple initiations to propagation are discussed in detail. It was found that the computational results obtained from the PD fatigue model were consistent with those from the test data. The angular errors of multiple cracks are within 2.66% and the number of cycles errors are within 15%. A comparison of test data and computational results indicates that the fatigue model can successfully capture multiple crack formations and propagation, and other behaviors of aluminum alloy material.

Ensemble local mean decomposition has been gradually introduced into mechanical vibration signal processing due to its excellent performance in electroencephalogram signal analysis. However, an unsatisfactory problem is that ensemble local mean decomposition cannot effectively process vibration signals of complex mechanical system due to the constraints of moving average. The process of moving average is time-consuming and inaccurate in complex signal analysis. Therefore, an improved ensemble local mean decomposition method called C-ELMD with modified envelope algorithm based on cubic trigonometric cardinal spline interpolation is proposed in this article. First, the shortcomings in sifting process of ensemble local mean decomposition is discussed and, furthermore, advantages and disadvantages of the common interpolation methods adopted to improve ensemble local mean decomposition are compared. Then, cubic trigonometric cardinal spline interpolation is employed to construct the local mean and envelope curves in a more precise way. In addition, the influence of shape-controlling parameter on envelope estimation accuracy in cubic trigonometric cardinal spline interpolation is also discussed in detail to select an optimal shape-controlling parameter. The effectiveness of cubic trigonometric cardinal spline interpolation for improving the accuracy of ensemble local mean decomposition is demonstrated using a synthetic signal. Finally, the proposed cubic trigonometric cardinal spline interpolation is tested to be effective in gear and bearing fault detection and diagnosis.

BackgroundThere were limited studies on the effect of skin temperature and local blood flow using kinesio tape (KT) adhered to the skin in different taping methods. This study aimed to determine the short-term effect of KT and athletic tape (AT) on skin temperature in the lower back and explore the possible effect of different taping methods (Y-strip and fan-strip taping) on local microcirculation.Materials and MethodsTwenty-six healthy participants completed the test-retest reliability measurement of the infrared thermography (IRT), intraclass correlation coefficient (ICC), and standard error of measurement (SEM) were calculated to evaluate the reliability. Then, 21 healthy participants received different taping condition randomly for 5 times, including Y-strip of kinesio taping (KY), fan-strip of kinesio taping (Kfan), Y-strip of athletic taping (AY), fan-strip of athletic taping (Afan), and no taping (NT). Above taping methods were applied to the participants’ erector spinae muscles on the same side. Skin temperature of range of interest (ROI) was measured in the taping area through IRT at pre taping and 10 min after taping. Additionally, participants completed self-perceived temperature evaluation for different taping methods through visual analog scaling. One-way repeated-measured analysis of variance was used to compare the temperature difference among different taping methods. Bonferroni test was used for post hoc analysis.ResultsThere was a good test-retest reliability (ICC = 0.82, 95% CI = 0.60–0.92; SEM = 0.33; and MD = 0.91) of the IRT. Significant differences were observed in the short-term effect on skin temperature among all different taping methods (p = 0.012, F = 3.435, and ηp2 = 0.147), post hoc test showed a higher significantly skin temperature difference in Kfan taping compared to no taping (p = 0.026, 95% CI = 0.051–1.206); However, no significant differences were observed among self-perceived temperature (p = 0.055, F = 2.428, and ηp2 = 0.108).ConclusionThis study showed that the fan-strip of KT increased significantly the skin temperature of the waist after taping for 10 min. The application of KT may modify the skin temperature of the human body and promote local microcirculation, although it remained unclear for the real application.

This paper presents a fully integrated C-band Doherty power amplifier (DPA) based on a 0.25-μm GaN-HEMT process for the 5G massive MIMO application. The performance degradation caused by nonlinear output capacitance is analyzed, and a novel compensation technique is proposed. A low-Q output network is employed to broaden the bandwidth, and its insertion loss in the back-off region is demonstrated to be mainly decided by the Q-factor of the drain bias inductor of the main PA. Hence, by adopting on-chip transmission lines with high Q-factors for drain biasing, a full integration, and a low loss can be achieved simultaneously. Reversed uneven power splitting and back-off input matching are proposed for gain enhancement. The fabricated DPA demonstrates a small-signal gain of 8.6-11.6 dB, an output power of 40.4-41.2 dBm, a 6-dB back-off drain efficiency (DE) of 47% - 50%, and a saturation DE of 55%-63% across a wide bandwidth from 4.5 to 5.2 GHz, with an ultra-compact size of 2.2 mm × 2.1 mm. Using a 40-MHz LTE signal with a 7.7-dB peak-to-average power ratio at the carrier frequency of 4.9 GHz, the measured average output power and efficiency are 33 dBm and 43%, respectively. The raw adjacent channel power ratio is -29 dBc and is improved to -46 dBc by applying digital predistortion.

Abstract Background Diffuse intrinsic pontine glioma (DIPG) is the main cause of pediatric brain tumor death. This study was designed to identify key genes associated with DIPG. Methods The gene expression profile GSE50021, which consisted of 35 pediatric DIPG samples and 10 normal brain samples, was downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were identified by limma package. Functional and pathway enrichment analyses were performed by the DAVID tool. Protein–protein interaction (PPI) network, and transcription factor (TF)–microRNA (miRNA)–target gene network were constructed using Cytoscape. Moreover, the expression levels of several genes were validated in human glioma cell line U251 and normal glia HEB cells through real-time polymerase chain reaction (PCR). Results A total of 378 DEGs were screened (74 up-regulated and 304 down-regulated genes). In the PPI network, GRM1, HTR2A, GRM7 and GRM2 had higher degrees. Besides, GRM1 and HTR2A were significantly enriched in the neuroactive ligand–receptor interaction pathway, and calcium signaling pathway. In addition, TFAP2C was a significant down-regulated functional gene and hsa-miR-26b-5p had a higher degree in the TF-miRNA-target gene network. PCR analysis revealed that GRM7 and HTR2A were significantly downregulated while TFAP2C was upregulated in U251 cells compared with that in HEB cells (p

Abstract The synergistic effect of conventional flame-retardant elements and graphene has received extensive attention in the development of a new class of flame retardants. Compared to covalent modification, the non-covalent strategy is simpler and expeditious and entirely preserves the original quality of graphene. Thus, non-covalently functionalized graphene oxide (FGO) with a phosphorus–nitrogen compound was successfully prepared via a one-pot process in this study. Polyethyleneimine and FGO were alternatively deposited on the surface of a poly(vinyl alcohol) (PVA) film via layer-by-layer assembly driven by electrostatic interaction, imparting excellent flame retardancy to the coated PVA film. The multilayer FGO-based coating formed a protective shield encapsulating the PVA matrix, effectively blocking the transfer of heat and mass during combustion. The coated PVA has a higher initial decomposition temperature of about 260 °C and a nearly 60% reduction in total heat release than neat PVA does. Our results may have a promising prospect for flame-retardant polymers.

In the present study, flavor profiles of Chinese spiced beef in the cooking process were comparatively analyzed by electronic nose, gas chromatography–mass spectrometry (GC–MS) with a thermal desorption system (TDS), and solid-phase microextraction (SPME). A total of 82 volatile compounds were identified, and 3-methyl-butanal, pentanal, hexanal, ρ-xylene, heptanal, limonene, terpinene, octanal, linalool, 4-terpinenol, α-terpineol, and (E)-anethole were identified as the characteristic flavor compounds in Chinese spiced beef. Variation in the content of volatile components produced by different cooking processes was observed. In general, a cooking time of 4 h resulted in optimal flavor quality and stability. Results indicated that the electronic nose could profile and rapidly distinguish variation among different cooking time. The volatile profiling by TDS-GC–MS and responses from the electronic nose, in combination with multivariate statistical analysis, are a promising tool for control the cooking process of spiced beef.

Abstract A novel hybrid flame retardant combining graphene oxide (GO) with long-chain phosphaphenanthrene was fabricated via surface grafting reaction. Taking advantageous of the double barrier effects, including the physical shield contributed by graphene nanoplates during the initial stage and the chemical char contributed by phosphaphenanthrene during the later stage, greatly decreased the release rate of decomposed volatiles from the resin, as well as minimized the release of oxygen and combustion heat. Hence, such hybrid flame retardant can overcome the shortcomings of early acid catalyzed degradation effects caused by conventional flame retardants containing phosphorus. Satisfactory flame retardance was achieved (UL94 V-0 rating) with only 4% addition of the hybrid flame retardant to the epoxy resin laminate. Due to the long-chain and bulky phosphaphenanthrene groups, the interlayer attractive forces of the modified GO were effectively weakened, thus favoring the exfoliation and dispersion of graphene sheets. As a result, the incorporation of the flame retardant slightly enhanced the mechanical properties of the polymer composites, rather than deteriorating them, as occurs with traditional additive flame retardants. As a potential application for graphene, it is believed that the reported hybrid flame retardant has promising future prospect.