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Attitude tracking on the unit sphere of dimension 3 based on sliding mode is considered in this article. The tangent bundle of Lagrangian dynamics that describes the rotational motion of a rigid body is first equipped with the structure of a Lie group, then a sliding subgroup emerged on it is defined. Next, a sliding‐mode controller is designed for attitude tracking that relies on an intrinsic error defined on the Lie group. Almost global asymptotic stability of the closed loop is demonstrated using the Lyapunov analysis. Comparisons of the proposed geometric sliding mode controller designed on the nonlinear manifold with one designed in the Euclidean space showed that under the same working conditions the former is more energy efficient, more robust to measurement noises, and has a shorter and smoother transient response. [ABSTRACT FROM AUTHOR]

Unilateral kidney hypoplasia is a congenital condition characterized by the underdevelopment of one kidney. Although often asymptomatic, it can cause severe renal complications in patients combined with contralateral renal injury, leading to acute renal failure. This case report describes a patient with unilateral kidney hypoplasia who underwent a kidney biopsy on the contralateral normal‐sized kidney and subsequently developed oliguric acute kidney injury. This report discusses the challenges encountered while diagnosing and managing this rare case, highlighting the importance of awareness and recognition to perform timely intervention and optimize the patient's outcome. [ABSTRACT FROM AUTHOR]

This paper proposes a secondary‐side semi‐active series resonant converter with hybrid control. Compared with the traditional series resonant converter (SRC), the converter only replaces two diodes with metal oxide semiconductor field effect transistors (MOSFETs) on the secondary side of the transformer, without adding any auxiliary components. By employing hybrid modulation scheme, the proposed converter can achieve a wide output voltage range in a narrow switching frequency range with high efficiency and has excellent soft‐switching performance. Due to the large magnetizing inductor and narrow switching frequency range, the proposed converter can achieve energy delivery with high efficiency and high power density. This paper provides a detailed introduction to the working principle, circuit characteristics, and design process of the converter. Finally, a 3.3 kW SiC‐based experimental prototype with 400 V input, 250–430 V output, and a switching frequency of 120–140 kHz is built to verify the theoretical analysis, and the peak efficiency reaches 97.82%. [ABSTRACT FROM AUTHOR]

In this paper, a control method combined with variable frequency and phase shifting is proposed, the primary purpose of which is to optimize the operating efficiency of the phase‐shift full‐bridge (PSFB) DC‐DC converter. By modeling the losses of the PSFB converter, the optimal switching frequency related to the load conditions is found. A neural network aided variable frequency controller that can work linearly is built to achieve the proposed method. At the same time, the voltage control loop is retained to ensure the stability of the output voltage and the necessary dynamic response of the converter. This paper builds an experimental platform for a 2 kW PSFB DC‐DC converter to verify the effectiveness of the proposed control method. With the control method proposed in this paper, the PSFB converter can always work at the optimum efficiency point under different load conditions. In addition, this paper also analyzes the influence of variable frequency control on PSFB operating states, such as zero‐voltage‐switching (ZVS) constraints, continuous conduction mode (CCM) operating states, and power density, which have an impact on its operating conditions. [ABSTRACT FROM AUTHOR]

Arylalkylamine N‐acetyltransferase (aaNAT) is a crucial enzyme that catalyses the transfer of acetyl groups from acetyl coenzyme A to arylalkylamines and arylamines. Evolutionary studies have identified a distinct class of aaNATs specific to mosquitoes, yet their functions remain elusive. This study focuses on Ae‐aaNAT7, a mosquito‐unique gene in Aedes aegypti (Diptera:Culicidae), to explore its functionality. Temporal and spatial expression analysis of Ae‐aaNAT7 mRNA revealed high expression during embryonic development and in first‐instar larvae, with notable expression in the limbs of adult mosquitoes based on tissue expression profiling. By further employing CRISPR/Cas9 technology for loss‐of‐function studies, our investigation revealed a reduction in the area of white spotting in the limbs of Ae‐aaNAT7 mutant adult mosquitoes. Further investigation revealed a significant decrease in the fecundity and hatchability of the mutants. Dissection of the ovaries from Ae‐aaNAT7 heterozygous mutants showed a noticeable reduction in the oocyte area compared with wild type. Dissection of the exochorion of the eggs from Ae‐aaNAT7 homozygous mutants consistently revealed a striking absence of mature embryos. In addition, RNA interference experiments targeting Ae‐aaNAT7 in males resulted in a reduction in fecundity, but no effect on hatchability was observed. These collective insights underscore the substantial impact of Ae‐aaNAT7 on reproduction and its pivotal contribution to adult limb pigmentation in Ae. aegypti. These revelations offer insights pivotal for the strategic design of future insecticide targets. [ABSTRACT FROM AUTHOR]

With the development of the high‐end equipment technology, the performance requirements of the internal gear pump (IGP) under high pressure are also increasing. However, the increase of working pressure will lead to the instability of gear pump performance in terms of volumetric efficiency, noise, reliability and so on, it is necessary to reasonably evaluate the reliability level of high‐pressure IGP. The reliability analysis of the high‐pressure IGP is carried out from the aspects of flow, noise, and gear strength in this paper. First, the output flow rate and far‐field flow‐induced noise of the high‐pressure IGP were obtained through fluid numerical simulation, and experimental verification was conducted. Then, based on the time‐varying meshing stiffness, backlash function and static transmission error of the gear pair, a nonlinear dynamic model of the internal meshing gear pair was established. The time‐varying meshing force was obtained through the dynamic model of the gear pair, and then the tooth contact stress and tooth root bending stress were obtained. Finally, considering the uncertain factors affecting the performance of the high‐pressure IGP, Latin hypercube sampling (LHS) combined with dendrite network (DD) was used for random response modeling. The performance reliability of the high‐pressure IGP, including output flow rate, far‐field flow‐induced noise, and the strength of gear pair, were estimated based on the fourth moment‐based saddlepoint approximation (FMSA). The reliability analysis results can provide a theoretical basis for the structural optimization design of the high‐pressure IGP. [ABSTRACT FROM AUTHOR]

Ship detection in synthetic aperture radar (SAR) images is widely applied in marine monitoring. In recent years, convolutional neural networks (CNNs) have made significant advances in SAR ship detection. However, the scene imbalance problem, i.e. much more offshore scenes than inshore scenes in SAR images, severely hampers the improvement of detection accuracy. In this article, we propose scene-aware data augmentation to address the problem. First, a novel concept, inshore rate, is introduced to estimate the land area percentage of various scenes in SAR images. We can divide image samples into inshore and offshore ones based on the inshore rate without manual category annotations. Second, to augment inshore samples, we synthesize dummy inshore images by cropping the ground truth bounding boxes (GT bboxes) from offshore images and pasting them onto inshore images. This offline data augmentation strategy can address the scene imbalance problem and improve detection accuracy. The experiments conducted on SAR Ship Detection Dataset (SSDD) and Large-Scale SAR Ship Detection Dataset (LS-SSDD) demonstrate the effectiveness of the proposed method in improving detection performance. [ABSTRACT FROM AUTHOR]

Oxidative coupling of methane (OCM) is a promising process of direct transformation of CH4 to ethylene instead of a complicated two-step process in terms of first forming syngas through reforming or partial oxidation and then producing ethylene with Fischer–Tropsch synthesis (FTS). Na2WO4 has been one of the most studied catalysts of OCM. Here we investigated how the introduced transition metal elements Co, Mn, or Mo to Na2WO4 could influence the catalytic performance of OCM on the supported Na2WO4. It is found that Co, Mn and Mo can obviously promote catalytic activity of transforming CH4 and selectivity for producing ethylene and ethane in OCM performed on Na2WO4 supported on microporous silicate-1 (S-1). A similar promotion of Co, Mn and Mo to the catalytic activity and selectivity in OCM performed on Na2WO4 was found when the Na2WO4 was supported on Matériaux de l′Institut Lavoisier-53(Al) [MIL-53(Al)]. X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy studies of these catalysts with added transition metal Co, Mn or Mo show that these metals diffused into the lattice of Na2WO4, further suggesting that the promotional effect likely arises from modification of the active phase of the supported Na2WO4 during OCM. [ABSTRACT FROM AUTHOR]

The primary goal of this study is to examine the impact of sodium hydroxide (NaOH)/alkali-activated fly ash on the fresh properties and mechanical properties of self-compacting concrete (SCC). The fresh properties, known as the workability of SCC characteristics, were determined using the U-box, V-funnel, J-ring, and L-box tests. The M30 grade SCC containing superplasticizer of 0.86 wt. % of cement is replaced with 10%, 15%, 20%, 25%, 30%, and 40% of alkali-activated fly ash. On days 7, 14, and 28 after curing, the compressive strength and the splitting tensile strength of the SCC were examined. The study was further extended to evaluate the behavior of reinforced concrete beams containing fly ash and ground granulated blast furnace slag, whose size was 1200 × 100 × 150 mm3, under flexure loading. Based on the test results, it was found that the increase in the replacement of cement with alkali-activated fly ash increased the workability in the SCC. With the addition of superplasticizers, the SCC gained much more workability than conventional concrete containing no superplasticizer. The mechanical properties of 10% and 15% activated fly ash in Portland cement provided the maximum strength for the SCC at different ages of curing. The maximum first crack load and maximum ultimate flexure loading of the reinforced concrete beam containing 10% activated fly ash by weight of cement were greater than those of the control concrete beam. The microstructural scanning electron microscope observations confirmed that the alkali-activated fly ash increased the strength properties of the self-compacting concrete. [ABSTRACT FROM AUTHOR]

The magnetization mechanism of Co-doped BaTiO3 ultrathin films is a subject of debate, which results in difficulties with the design of new multiferroics based on BaTiO3 matrixes. With the aid of a first-principles approach, it was observed that when the interstitial site and Ti vacancy were filled with Co, the configuration behaved in a nonmagnetic manner, indicating the significance of the Co content. Moreover, in the case of Co substituting two neighboring Ti atoms, when a direct current field was applied in the [100] direction, the magnetic domains excluding those in the [100], [010], and [001] directions were directed away. Further, the magnetoelectric constant was evaluated at ~449.3 mV/cmOe, showing strong magnetoelectric coupling at room temperature. Clearly, our study indicates that strict control of Ba, Ti, O, and Co stoichiometry can induce an electric and magnetic field conversion in two-dimensional BaTiO3 and may provide a new candidate for single-phase multiferroics for application in next-generation multifunctional devices. [ABSTRACT FROM AUTHOR]

When the resonant converters are connected in parallel, the output current is unbalanced without additional current‐sharing measures due to differences in resonant component. In the input‐parallel output‐parallel resonant converter system, the output voltage accuracy of the converter under the traditional droop control is analyzed when the load changes. In this paper, an adaptive droop control is proposed, in which the droop coefficient is adaptively adjusted as the load changes. The control method proposed in this paper realizes the current sharing between the converters and solves the shortcomings of the output voltage changing under different loads in the conventional droop control. Taking two parallel LLC converters as an example, the control block diagram of the parallel control method for adaptive adjustment of the droop coefficient proposed in this paper is given, and the stability of the control loop is analyzed. Finally, two parallel prototypes of LLC converters with input 200 V/output 24 V input are built by digital control, and the experiment shows that the proposed control method improves the shortcomings of excessive output voltage droop caused by traditional droop control during dynamic load switching, which verifies the effectiveness of the method. [ABSTRACT FROM AUTHOR]

Objectives: We previously analysed the preparedness to deliver a disease-modifying Alzheimer's treatment in the United Kingdom and predicted substantial wait times. This study updates the prediction for the National Health Service (NHS) in England, using an improved model and newer data. Methods: We reviewed published data on capacity for diagnosis of cognitive impairment combined with expert input and constructed a model for wait times to access from 2023 to 2043. The model tracks patients from initial evaluation in primary care, cognitive testing by a dementia specialist, confirmatory biomarker testing with positron emission tomography (PET) scans or examination of cerebrospinal fluid and infusion delivery. Capacity for specialist visits and PET scans are assumed to be capacity constrained, and cerebrospinal fluid testing and infusion delivery to be scalable. Results: Capacity constraints were projected to result in substantial wait times: patients referred to specialists based on a brief cognitive test, which is the current standard of care, would expect an overall initial wait times of 56 months in 2023, increasing to 129 months in 2029 and then falling slowly to around 100 months. Use of a blood test for the confirmation of Alzheimer's pathology as an additional triage step, would reduce wait times to around 17 to 25 months. Discussion: The NHS England lacks capacity to provide timely access to a disease-modifying treatment, which is estimated to result in significant wait times and potentially avoidable disease progression. Better diagnostic tools at initial evaluation may reduce delays. [ABSTRACT FROM AUTHOR]

To achieve a coating density meeting the solid oxide fuel cell (SOFC) electrolyte requirements of high gas tightness and ionic conductivity, in this study, a new interface healing densification process based on a liquid-phase sintering induction mechanism was conducted on plasma-sprayed 8 mol% Y 2 O 3 -stabilized ZrO 2 (8YSZ) coatings. Using Fe 2 O 3 and Bi 2 O 3 as healing additives, metallurgical healing of unbound interfaces was achieved by impregnating the additives into the gap interfaces, followed by liquid-phase sintering at 1200 and 1050 °C. After healing, the YSZ coating exhibited a dense bulk-like microstructure with a significant reduction in the gas leakage rate by two orders of magnitude, and the oxygen ion conductivity of the coating was significantly increased. The YSZ coating healed with the Fe 2 O 3 additive showed an oxygen ionic conductivity nearly one order of magnitude higher than that of the as-sprayed coating, reaching more than 80% of the value of the high-temperature-sintered YSZ bulk. • A new interface healing process based on liquid-phase sintering was conducted on APS YSZ coatings. • The interface-healed YSZ coating exhibited a dense bulk-like microstructure. • The gas leakage rate of the interface-healed YSZ coating decreased by two orders of magnitude. • Ionic conductivity of the interface-healed YSZ coating reached > 80% of the sintered bulk. • The cell assembled with interface-healed YSZ-Fe 2 O 3 electrolyte achieved MPD of 1.04 W/cm2 at 800 °C. [ABSTRACT FROM AUTHOR]

Background: Obesity is closely associated with lipid accumulation, inflammation and intestinal microbiota dysbiosis. Short‐ and long‐chain type structured lipids (SLCTs) are kinds of low‐calorie structured lipids and demonstrate anti‐obesity and hypolipidemia bioactivity. The objective of this study is to investigate the potential effects of dietary supplementation of SLCTs rich in short‐chain fatty acids and polyunsaturated fatty acids on high‐fat‐diet‐induced obesity and gut microbiota modulation in C57BL/6J mice. Results: Results showed that SLCTs supplementation ameliorated body weight, dyslipidemia, liver lipid accumulation, liver injury and systemic inflammation in obese mice. As expected, immunohistochemical analysis showed that SLCTs significantly increased the expression of proliferator‐activated receptor alpha and decreased the expression of Toll‐like receptor 4 in liver tissue. Furthermore, SLCTs supplementation significantly downregulated the expression level of liver inflammation‐related genes while upregulating the expression level of liver lipid metabolism‐related genes. Additionally, SLCTs supplementation markedly enhanced the diversity of gut microbiota, reduced the Firmicutes/Bacteroidetes ratio and increased the diversity and richness of beneficial intestinal microorganisms, such as Bacteroides, Lactobacillus, Lachnospiraceae NK4A136 group, Alloprevotella and Ruminococcaceae UCG‐014. Conclusion: Our work suggested that SLCTs may have the potential to reduce obesity associated with a high‐fat diet by regulating liver metabolism, inflammation and gut microbiota. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Despite the promise of therapeutic antibodies in engaging the immune system to eliminate malignant cells, many aspects of the complex interplay between immune cells and cancer cells induced by antibody therapy remain incompletely understood. This study aimed to develop a biosensor system that can evaluate direct cell-cell physical contact and interactions between immune effector and target cells induced by therapeutic antibodies in physiologically relevant environments. The system uses two structural complementary luciferase units (SmBit and LgBit) expressed on the respective membranes of effector and target cells. Upon cell-cell contact, the two subunits form active NanoLuc, generating a luminescent signal, allowing for real-time monitoring of cell-cell interactions and quantitatively assessing the pharmacological effects of therapeutic antibodies. We optimized the system to ensure selectivity by adjusting the spacer lengths between two luciferase units to minimize interference from nonspecific intercellular contact. The system was applied to quantitatively monitor cell-cell interactions between NK and target cells induced by rituximab and between T and target cells induced by blinatumomab in a 3D cell culture system. The biosensor system has the potential to characterize antibody pharmacology through a deeper understanding of antibody-mediated cell-cell interactions. [ABSTRACT FROM AUTHOR]

Ethylene-propylene block copolymer (EbP) is a vital component in impact polypropylene copolymer (IPC), yet its distribution in the multiphase composite material and how it influences the phase structure and the mechanical properties are not well understood. In this work, four IPCs were investigated by atomic force microscopy-infrared (AFM-IR) to assess the phase compositions in situ, based on which in conjunction with the chain microstructure information obtained ex situ the distributions of the copolymer components were derived for each alloy. For the IPCs whose EbP comprises long P and long E segments, the EbP fraction was found to phase separate from the rubber and the PP matrix to form the cores of the disperse particles with the E-P segmented copolymer (EsP). In contrast, in the IPC with EbP composed of long P and short E segments, the EbP fraction formed an outer shell for the rubber particles with the cores comprising the EsP alone, and this IPC, containing a lower E comonomer content than its counterpart, exhibited both better impact resistance and higher flexural modulus. These results clarify how the chain structure of EbP governs the phase morphology in IPC, which in turn impacts the properties of the composite material. [ABSTRACT FROM AUTHOR]

An 8-year-old girl presented with a 34-day history of cough, fatigue, and impaired exercise tolerance. She experienced cyanosis on exertion but denied fever, hemoptysis, hematuria, or seizures. Her perinatal and family histories were unremarkable, and she had no history of exposure to TB. A chest radiogram from a local clinic showed diffuse pulmonary lesions. Tuberculin skin test, interferon-γ release assay, and HIV antibody test results were all negative. Immunoglobulin levels and lymphocyte subsets were normal. The patient did not respond to IV azithromycin for 1 week for community-acquired pneumonia. She was transferred to our hospital because of progressive respiratory distress and hypoxemia. [ABSTRACT FROM AUTHOR]

The uniaxial tensile mechanical properties of PVC foam considering the effects of strain rate ( ε ˙ = 0.0007 − 523 s − 1 ) and anisotropy (R = 1 − 1.57) have been investigated by quasi-static and dynamic (Split Hopkinson Tensile Bar, SHTB) tests. Combined high-speed camera system and Digital Image Correlation (DIC) technique, the real-time surface strain field of the specimen during the whole tensile process was obtained. On this basis, the macroscopic response and failure mode of PVC foam were investigated. The failure mechanism of PVC foam under tensile loading was revealed through Scanning Electron Microscope (SEM) images on fracture cross-section of loaded specimen. Finally, based on experimental data, a prediction equation on tensile strength of PVC foam considering the effects of strain rate and loading angle (anisotropy) is proposed. Furthermore, a nonlinear constitutive model is developed to describe the uniaxial tensile mechanical properties of PVC foam. [ABSTRACT FROM AUTHOR]

Oxidative stress is an important mechanism of aging, and in turn, aging can also aggravate oxidative stress, which leads to a vicious cycle. In the process of the brain converting light into visual signals, the eye is stimulated by harmful blue‐light radiation directly. Thus, the eye is especially vulnerable to oxidative stress and becomes one of the organs most seriously involved during the aging process. Cataracts, age‐related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), and dry eye are inextricably linked to the aging process and oxidative stress. Chlorogenic acid (CGA) has been demonstrated to have antioxidant and anti‐inflammatory activities, and its validity has been established experimentally in numerous fields, including cardiovascular disease, metabolic disorders, cancers, and other chronic diseases. There has previously been evidence of CGA's therapeutic effect in the field of ophthalmopathy. Considering that many ophthalmic drugs lead to systemic side effects, CGA may act as a natural exogenous antioxidant for patients to take regularly, controlling their condition while minimizing side effects. In this paper, in vitro and in vivo studies of CGA in the treatment of age‐related eye diseases are reviewed, and the prospects of CGA's antioxidant application for the eye are discussed. The aim of this review is to summarize the relevant knowledge and provide theoretical support for future research. [ABSTRACT FROM AUTHOR]

This paper proposes a new hybrid control strategy to solve the problem of bidirectional wide voltage range regulation in CLLC converters. On the (LLC) side (G2V direction), the SSSA control method is employed for voltage boost, combined with bus voltage and burst control to achieve wide voltage regulation. On the (C) side (V2G direction), the SSSA and full/half‐bridge mode switching control are used to achieve V2G direction wide voltage regulation. This hybrid control strategy also enables high conversion efficiency in both directions without the need for additional components to reduce the converter power density. This is particularly suitable for OBC applications with strict requirements for converter volume and weight. A detailed analysis with mathematical derivation, hybrid control strategy, and converter operation principles is introduced in this paper. The following subchapters supplement the converter voltage gain, soft switching implementation conditions, and design considerations. Finally, the feasibility of the proposed control strategy was verified through an experimental prototype with an input voltage ranging from 340 to 430 V to an output voltage ranging from 225 to 450 V and bidirectional rated power of 6.6/3.3 kW. This prototype achieved a maximum conversion efficiency of 97.7% in the G2V direction and 97.1% in the V2G direction. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of Cu doping on the thermoelectric properties of BiSbTe3 (BST) alloys. Firstly, we successfully prepared high-quality BST alloys using the KCl solvent method and selected the most promising BST(KCl)3.5 sample from them, followed by Cu doping experiments. The experimental results show that Cu doping significantly improves the crystal quality and density of the alloy, thereby increasing the material's mobility and reducing the resistivity, leading to an improvement in the power factor. However, Cu doping also introduces a large number of dislocations and lattice distortions. Additionally, the highly doped samples contain Cu2Te and BST superlattice structures, which further enhance the scattering of heat transfer phonons, significantly reducing the lattice thermal conductivity. In the experiment, Cu-doped samples exhibited extremely low lattice thermal conductivity, as low as 0.32 W m−1 K−1 at 300 K. These improvements in structure and performance have greatly enhanced the thermoelectric efficiency of Cu-doped samples, leading to a significant increase in their ZT values. Particularly, in samples with a Cu doping level of x = 0.01, the maximum ZT value was 1.47 at 400 K, and the average ZT value reached 1.28 in the temperature range of 300 K to 450 K. These findings underscore the wide-ranging application potential of Cu-doped BiSbTe3 alloys in room temperature refrigeration and power generation. The study provides crucial insights into the characteristics of Cu-doped BiSbTe3 alloys, while also contributing to the optimization of thermoelectric material design and the advancement of sustainable energy conversion technologies. [ABSTRACT FROM AUTHOR]

The presently available commercial photodetectors have a broadband photoresponse and require different external optical filters to block the undesired light outside the detection spectrum window, e.g., near-infrared (NIR) detection. The use of an NIR bandpass has technical limitations in curved or flexible large-area photodetectors, as an NIR bandpass depends critically on the difference in the interference of the optical path in the filter. This work reports the effort to develop a high-performance filter-free organic photodetector (OPD) with a double bulk heterojunction (BHJ) structure. The visible-blind NIR photodetection is realized by eliminating the photocurrent generated in the front visible light-absorbing BHJ optical depletion layer, due to the suppression of electron transport by incorporating a copper thiocyanate-based electron-blocking layer in the OPD. Only excitons generated in the rear NIR-absorbing BHJ contribute to photocurrent in the OPD, thereby achieving visible-blind NIR photodetection. The double BHJ OPD has a high responsivity of 0.38 A/W at 1050 nm and a specific detectivity of >1013 Jones over the wavelength range from 800 to 1050 nm, making it an ideal candidate for applications in optical communication, food quality detection, wellness monitoring, and NIR image sensors. [ABSTRACT FROM AUTHOR]

The construction of an interface has been demonstrated as one of the most insightful strategies for designing efficient catalysts toward electrochemical CO2 reduction (CO2RR). However, the weak interfacial interaction and inherent instability inevitably hinder a further performance enhancement in CO2RR attributable to the interface effect. Herein, 2 nm Ag nanoclusters (Ag NCs) are embedded onto CeO2 nanospheres (CeO2 NSs) with highly interconnected porosity (Ag NCs@CeO2 NSs) to exclusively study the pure interface effect toward CO2RR. The enhanced Ag–CeO2 pure interface endows Ag NCs@CeO2 NSs with a remarkably larger current density, significantly higher Faraday efficiency (FE), and energy efficiency as compared to Ag NCs, CeO2 NSs, and the one with Ag NCs dispersed on CeO2 nanoparticles. More importantly, an impressively high CO FE of over 70.0% is achieved at an ultralow overpotential (η) of 146 mV. The free energy and differential charge calculations, coupled with X‐ray photoelectron spectroscopy results jointly imply that the effective initiation of CO2RR to CO at a lower η over Ag NCs@CeO2 NSs derives from the enhanced interface‐induced charge delocalization, which enhances the electron transfer ability toward *COOH intermediate, thus overcoming the energy barrier demanded for the rate‐determining step. [ABSTRACT FROM AUTHOR]

This work presents the experimental characterization and improved model of multi-strand entangled metallic wire materials (MS-EMWMs). MS-EMWM is a novel damping material made of several strands of entangled wires using a modified manufacturing process. Six batches of specimens were fabricated and tested under quasi-static loading. Secant stiffness and loss factor were calculated to indicate the mechanical properties. The results showed that MS-EMWM has the characteristics of high damping energy dissipation compared to EMWM. A micro-multi-strand spiral spring model was proposed to predict the mechanical properties of MS-EMWM. The probability distribution of micro-spring pairs between wires was used to characterize the random combination of materials. According to the results, the improved model can effectively reflect the mechanical behavior of MS-EMWM. The mechanical properties of MS-EMWM were predicted by the coefficient matrix obtained by particle swarm optimization. Through the prediction and test results, the predicted results are acceptable. [ABSTRACT FROM AUTHOR]

Speaker identification based on deep learning is known to be susceptible to backdoor attacks. However, the current research on audio backdoor attacks is limited, and these attacks often use obvious noises as triggers, which can raise suspicion among users. In this paper, we introduce SilentTrig, a novel and imperceptible backdoor attack method targeted at speaker identification. Our approach involves utilizing an optimized steganographic network to embed triggers into benign audio samples and implementing a two-stage adversarial optimization process. This ensures that the poisoned samples are acoustically indistinguishable from their benign counterparts, resulting in a substantially improved attack imperceptibility. We evaluate SilentTrig on two datasets and four state-of-the-art models. The results demonstrate a high Attack Success Rate (ASR) of up to 99.2%, a Just Noticeable Difference (JND) of only 0.3, and resistance to typical defense methods such as Neural Cleanse and Fine-Pruning. • Backdoor attack against speaker identification, improving the imperceptibility. • Optimized steganographic network for embedding triggers secretively. • Two-stage adversarial optimization to get indistinguishable malicious samples. • Designed malicious samples are effective and stealthy for attacks. [ABSTRACT FROM AUTHOR]

Introduction: Rheumatoid arthritis (RA) is a systemic chronic autoimmune disease in adults that is associated with significant joint issues and systemic inflammation. One of the signs of bone damage in RA is osteoporosis (OP). Leptin is an inflammatory protein that has been reported to be related to RA. The potential relationships among leptin, disease activity, and OP in Chinese patients with RA are not well known. Methods: In total, 245 patients with RA and 120 healthy controls were included in this study. Detailed data on the clinical characteristics and laboratory features were collected. Information about physical activity and functional status was recorded using specific questionnaires. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA). The MECALL castor-50-hf model X-ray scanner was used for the two-hand (including wrist) photographs. Results: Serum leptin levels differed significantly between the RA group and healthy control subjects (1.27/3.29 vs. 0.17/0.24, Z=13.29, P<0.001). The positive rate of leptin protein in RA patients was 86.35%, which was higher than that in controls (19.55%) (χ2=28.51, P<0.001). Pearson's correlation test showed that morning stiffness, disease duration, joint swelling, joint tenderness, swollen joint count (SJC), tender joint count (TJC), health assessment questionnaire (HAQ) score, and Sharp-van der Heijde method (Sharp) score were positively correlated with the level of serum leptin (r=0.212, r=0.312, r=0.322, r=0.501, r=0.291, r=0.334, P<0.05). There was a clear increasing trend in the level of serum leptin according to the different disease activity scores and in the 28 joint activity (DAS28) groups (F=13.936, P<0.001). Elevated leptin was a risk factor for increased disease activity and OP according to logistic regression analysis. The median leptin level differed significantly between the normal bone mass group, osteopenia group, and OP group (P<0.001). An increased serum leptin level was a risk factor for RA-induced osteoporosis according to logistic regression analysis (P<0.001). Conclusion: These results suggest that the level of serum leptin is associated with disease activity and secondary OP among Chinese patients with RA. Key Points • Serum leptin levels in RA patients are higher than those in normal control group. • Leptin was associated with disease activity. • Leptin was associated with the occurrence of systemic osteoporosis and affects bone erosion in RA patients. [ABSTRACT FROM AUTHOR]

Eukaryotic cells organize their genome within the nucleus with a double-layered membrane structure termed the nuclear envelope (NE) as the physical barrier. The NE not only shields the nuclear genome but also spatially separates transcription from translation. Proteins of the NE including nucleoskeleton proteins, inner nuclear membrane proteins, and nuclear pore complexes have been implicated in interacting with underlying genome and chromatin regulators to establish a higher-order chromatin architecture. Here, I summarize recent advances in the knowledge of NE proteins that are involved in chromatin organization, gene regulation, and coordination of transcription and mRNA export. These studies support an emerging view of plant NE as a central hub that contributes to chromatin organization and gene expression in response to various cellular and environmental cues. [ABSTRACT FROM AUTHOR]

Abstract Association scheme was first introduced by statisticians in connection with the design of experiments and has been proven very useful in many fields, including permutation groups, graphs, and coding theory. An array is called schematic if its runs form an association scheme with respect to distance. Schematic arrays, especially schematic orthogonal arrays, have been ideal tools used in designing experiments and generating software test suites. However, the definition of the original schematic array is too demanding. It not only requires the relationship between any two distinct rows, but also overemphasizes the single-row property. This drawback dramatically limits the existence results on schematic arrays. In this article, we modify the original conditions of the association scheme and propose the concept of the revised schematic array. We further elaborate on the rationality of the revised definition. Finally, we also provide two examples of revised schematic arrays, including three-level mirror-symmetric orthogonal arrays and Latin hypercube designs. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) remains a bottleneck for electrocatalytic water‐splitting to generate hydrogen. However, the traditional adsorbed evolution mechanism (AEM) possesses sluggish reaction kinetics due to the scaling relationship, while lattice oxygen mechanism (LOM) triggers an unstable structure due to the escaping of lattice oxygen. Herein, a proof‐of‐concept Fe‐Co(OH)2/Fe2O3 heterostructure is put forward, where Fe‐Co(OH)2 following AEM can complete rapidly deprotonation process while Fe2O3 following LOM can trigger O─O coupling step. Combining the theoretical and experimental investigation confirmed that the redistributed space‐charge of Fe‐Co(OH)2/Fe2O3 junction can optimize synergistically adsorbed and lattice oxygen, the coupling mechanism of AEM and LOM can facilitate synchronously the OER activity and stability. As a result, the Fe‐Co(OH)2/Fe2O3 heterostructure shows excellent OER performance with low overpotential of only 219 and 249 mV to reach a current density of 10 and 100 mA cm−2. Specifically, the Fe‐Co(OH)2/Fe2O3 electrocatalyst maintains excellent long‐term stability for 100 h at a large current density of 100 mA cm−2. This work paves an avenue to break through the limit of the conventional OER mechanism. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the compressive performance of longitudinal steel-fiber-reinforced polymer composite bars (SFCBs) in concrete cylinders confined by different type of fiber-reinforced polymer (FRP) composites. Three types of concrete cylinders reinforced with (or without) longitudinal SFCBs and different transverse FRP confinements were tested under monotonic compression. The results showed that the post-yield stiffness of SFCBs is higher when confined with high elastic modulus carbon fiber-reinforced polymer (CFRP) composite than with low elastic modulus basalt fiber-reinforced polymer (BFRP) composite. Decreasing confinement spacing did not significantly improve the compressive strength of SFCBs in concrete cylinders. The compressive failure strain of SFCBs could possibly reach 88% of its tensile peak strain in concrete cylinders confined by CFRP sheets, which is significantly higher than the value (around 50%) in previous studies. Existing design equations, which applied a strength reduction factor or a maximum compressive strain of concrete to consider the compressive contributions of SFCBs in concrete members, underestimate the load-carrying capacity of SFCB-reinforced concrete cylinders. The design equation that considers the actual compressive stress of SFCBs gives the most accurate prediction; however, its applicability and accuracy need to be verified with more experimental data. [ABSTRACT FROM AUTHOR]

With the rapid development of science and technology, microscale machining has become an important topic, and lubricants play a vital role in machining. Solid lubricants are suitable for a variety of precision machining better than liquid lubricants. Molybdenum disulfide (MoS2) in 2D‐layered nanomaterials is a promising candidate for use as a solid lubricant. Herein, molecular dynamics (MD) simulations are performed to study the effects of scratch depth, speed, and temperature on the mechanical properties of Ni‐based MoS2 thin films. The results show that atom stacking and extrusion around the abrasive tip increase the friction coefficient in the indentation and scratch phases. The higher value of scratch depths, speeds, and temperatures can lead to higher friction coefficients and wider dislocation distributions. Moreover, Shockley dislocation appears in all cases at all effects, and the total dislocation length increases with the higher value of scratch depths, speeds, and temperatures. [ABSTRACT FROM AUTHOR]

Silicon nanophotonics has attracted significant attention because of its unique optical properties such as efficient light confinement and low non-radiative loss. For practical applications such as all-optical switch, optical nonlinearity is a prerequisite, but the nonlinearity of silicon is intrinsically weak. Recently, we discovered a giant nonlinearity of scattering from a single silicon nanostructure by combining Mie resonance enhanced photo-thermal and thermo-optic effects. Since scattering and absorption are closely linked in Mie theory, we expect that absorption, as well as heating, of the silicon nanostructure shall exhibit similar nonlinear behaviors. In this work, we experimentally measure the temperature rise of a silicon nanoblock by in situ Raman spectroscopy, explicitly demonstrating the connection between nonlinear scattering and nonlinear heating. The results agree well with finite-element simulation based on the photo-thermo-optic effect, manifesting that the nonlinear effect is the coupled consequence of the red shift between scattering and absorption spectra. Our work not only unravels the nonlinear absorption in a silicon Mie-resonator but also offers a quantitative analytic model to better understand the complete photo-thermo-optic properties of silicon nanostructures, providing a new perspective toward practical silicon photonics applications. [ABSTRACT FROM AUTHOR]

BiFeO3-BaTiO3 is a promising high-temperature lead-free piezo-ceramics due to its high Curie temperature (TC > 500 °C) and excellent piezoelectric properties. However, a high leakage current was often detected in this system, which severely affects its applications. In this work, the 0.7BiFe(1−x)GaxO3-0.3BaTiO3 (BFGax-BT, 0.00 ≤ x ≤ 0.10) system was designed to reveal the reason of leakage-current density decreased by their leakage mechanism. Because of the suppression of generation of Fe2+ and oxygen vacancy ( V O ∙ ∙ ), the leakage mechanism from space charge limited conduction mechanism found in Ga-free BF-BT ceramics turns into Ohmic conduction and Schottky emission mechanism as Fe3+ was replaced with Ga3+. A good combination of piezoelectric properties (d33 = 174 pC N−1 and kp = 29%) and high Curie temperature (TC = 497 °C) was achieved in the BFGa0.06-BT ceramic owning the lowest leakage-current density. This work will provide the clues for preparing the high insulation and high piezoelectric performance BF-BT-based ceramics by suppressing the valence change of Fe3+ and V O ∙ ∙ appearance. [ABSTRACT FROM AUTHOR]

In this study, Bi2Se3 thermoelectric materials with high density, low thermal conductivity, and excellent thermoelectric performance are prepared using a Se slow-release method. It was found that the number of Se defects in the material could be effectively reduced by changing the content of NaCl solvent, and a certain number of Na atoms are introduced into the Bi2Se3 matrix. The carrier concentration of Bi2Se3 is greatly optimized due to the synergistic effect of the two, leading to a gradual increase in the Seebeck coefficient from −94 to −122 μV K−1 at room temperature. Simultaneously, we conducted an in-depth investigation into the effects of Na doping and Se vacancies on the electronic structure of the materials. Our findings indicate that the presence of these two defects gives rise to resonance energy levels and sharpens the density of state peaks near the Fermi level. This discovery further underscores the potential for enhancing thermoelectric performance. Finally, the Bi2Se3(NaCl)10 sample achieved the maximum ZT value of 0.69 at 550 K, and the average ZT within the temperature detection range reached 0.36, increasing the thermoelectric performance of the material. [ABSTRACT FROM AUTHOR]

Aiming at the problems of narrow ZVS range, large duty cycle loss, and severe voltage oscillation of phase‐shift‐controlled full‐bridge converters, this paper proposes a converter that realizes ZVS by adjusting the parallel current. No additional series inductor is required, avoiding large duty cycle loss and weakening voltage oscillations on the secondary side. The converter with small duty cycle loss can use a transformer with a larger turns ratio, which can reduce the voltage stress of the secondary diodes and the filter inductor current ripple. The parallel current required to realize ZVS is analyzed theoretically considering the influence of leakage inductor energy on ZVS. A comparative experiment between the proposed converter and the conventional full‐bridge converter is carried out to verify the performance of the proposed converter. [ABSTRACT FROM AUTHOR]

Bismuth telluride (Bi 2 Te 3) is a widely used thermoelectric (TE) material in practical applications. However, it contains expensive and toxic tellurium, a promising TE material should include low-cost and non-toxic element. Bismuth selenide (Bi 2 Se 3) is similar to Bi 2 Te 3 in electronic and crystal structure. The electron effective mass of Bi 2 Se 3 is smaller than that of Bi 2 Te 3 , while its electrical transport performance is inferior to that of Bi 2 Te 3. Therefore, in this study, Cl and K co-doped Bi 2 Se 3 thermoelectric material with high density, low thermal conductivity, and excellent thermoelectric performance was prepared using KCl as the solvent. It is found that the effective electron mass and carrier concentration of the doped sample is effectively improved, which significantly increases the doped sample's electrical transport properties and ZT value. Finally, the Bi 2 Se 3 (KCl) 3.5 sample reached a maximum ZT value of 0.79 at 550 K, and the average ZT in the measured temperature range reached 0.45. [ABSTRACT FROM AUTHOR]

Carbon isotope composition of tree‐ring (δ13CRing) is a commonly used proxy for environmental change and ecophysiology. δ13CRing reconstructions are based on a solid knowledge of isotope fractionations during formation of primary photosynthates (δ13CP), such as sucrose. However, δ13CRing is not merely a record of δ13CP. Isotope fractionation processes, which are not yet fully understood, modify δ13CP during sucrose transport. We traced, how the environmental intra‐seasonal δ13CP signal changes from leaves to phloem, tree‐ring and roots, for 7 year old Pinus sylvestris, using δ13C analysis of individual carbohydrates, δ13CRing laser ablation, leaf gas exchange and enzyme activity measurements. The intra‐seasonal δ13CP dynamics was clearly reflected by δ13CRing, suggesting negligible impact of reserve use on δ13CRing. However, δ13CP became increasingly 13C‐enriched during down‐stem transport, probably due to post‐photosynthetic fractionations such as sink organ catabolism. In contrast, δ13C of water‐soluble carbohydrates, analysed for the same extracts, did not reflect the same isotope dynamics and fractionations as δ13CP, but recorded intra‐seasonal δ13CP variability. The impact of environmental signals on δ13CRing, and the 0.5 and 1.7‰ depletion in photosynthates compared ring organic matter and tree‐ring cellulose, respectively, are useful pieces of information for studies exploiting δ13CRing. Summary statement: Intra‐annual tree‐ring δ13C signal of Scots pine recorded faithfully the environmental signal in leaf sucrose δ13C, with no clear signs of reserve use. The 13C‐enrichment of studied sink organs relative to leaves was dominated by post‐photosynthetic fractionations, such as sink organ respiration. [ABSTRACT FROM AUTHOR]

Background: We sought to explore the relationship between dexmedetomidine as an anesthetic adjuvant in cardiac surgery and postoperative complications and length of stay (LOS) in the cardiac intensive care unit (CICU). Methods: We conducted a retrospective study of patients aged 18 years and older who underwent heart valve surgery between October 2020 and June 2022. The primary endpoint of the study was major postoperative complications (cardiac arrest, atrial fibrillation, myocardial injury/infarction, heart failure) and the secondary endpoint was prolonged CICU LOS (defined as LOS > 90th percentile). Multivariate logistic regression analysis was performed for variables that were significant in the univariate analysis. Results: A total of 856 patients entered our study. The 283 patients who experienced the primary and secondary endpoints were included in the adverse outcomes group, and the remaining 573 were included in the prognostic control group. Multivariate logistic regression analysis revealed that age > 60 years (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.23–2.31; p < 0.01), cardiopulmonary bypass (CPB) > 180 min (OR, 1.62; 95% CI, 1.03–2.55; p = 0.04) and postoperative mechanical ventilation time > 10 h (OR, 1.84; 95% CI, 1.35–2.52; p < 0.01) were independent risk factors for major postoperative complications; Age > 60 years (OR, 3.20; 95% CI, 1.65–6.20; p < 0.01), preoperative NYHA class 4 (OR, 4.03; 95% CI, 1.74–9.33; p < 0.01), diabetes mellitus (OR, 2.57; 95% CI, 1.22–5.41; p = 0.01), Intraoperative red blood cell (RBC) transfusion > 650 ml (OR, 2.04; 95% CI, 1.13–3.66; p = 0.02), Intraoperative bleeding > 1200 ml (OR, 2.69; 95% CI, 1.42–5.12; p < 0.01) were independent risk factors for prolonged CICU length of stay. Intraoperative use of dexmedetomidine as an anesthetic adjunct was a protective factor for major complications (odds ratio, 0.51; 95% confidence interval, 0.35–0.74; p < 0.01) and prolonged CICU stay. (odds ratio, 0.37; 95% confidence interval, 0.19–0.73; p < 0.01). Conclusions: In patients undergoing heart valve surgery, age, duration of cardiopulmonary bypass, and duration of mechanical ventilation are associated with major postoperative complication. Age, preoperative NYHA classification 4, diabetes mellitus, intraoperative bleeding, and RBC transfusion are associated with increased CICU length of stay. Intraoperative use of dexmedetomidine may improve such clinical outcomes. [ABSTRACT FROM AUTHOR]

Background: Breast cancer (BC) has posed a great threat to world health as the leading cause of cancer death among women. Previous evidence demonstrated that germ cell-specific gene 2 (GSG2) was involved in the regulation of multiple cancers. Thus, the clinical value, biological function and underlying mechanism of GSG2 in BC were investigated in this study. Methods: The expression of GSG2 in BC was revealed by immunohistochemistry (IHC), qPCR and western blotting. Secondly, the biological function of GSG2 in BC was evaluated by MTT assay, flow cytometry, Transwell assay and wound healing assay. Furthermore, the potential molecular mechanism of GSG2 regulating the progression of BC by co-immunoprecipitation (Co-IP) and protein stability detection. Results: Our data indicated that GSG2 was frequently overexpressed in BC. Moreover, there was a significant correlation between the GSG2 expression and the poor prognosis of BC patients. Functionally, GSG2 knockdown inhibited the malignant progression of BC characterized by reduced proliferation, enhanced apoptosis and attenuated tumor growth. Migration inhibition of GSG2 knockdown BC cells via epithelial-mesenchymal transition (EMT), such as downregulation of Vimentin and Snail. In addition, E2F transcription factor 1 (E2F1) was regarded as a target protein of GSG2. Downregulation of E2F1 attenuated the promoting role of GSG2 on BC cells. Mechanistically, knockdown of GSG2 accelerated the ubiquitination of E2F1 protein, which was mediated by E3 ubiquitin ligase MDM2. Conclusions: GSG2 facilitated the development and progression of BC through MDM2-mediated ubiquitination of E2F1, which may be a promising candidate target with potential therapeutic value. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) faces many security and privacy risks due to the large number of devices accessing the network while providing convenience to the current society. At present, the management of IoT devices is centralized. All terminal devices are managed in a centralized manner, and the data accessing IoT devices can only be connected to the network with the permission of the centralized nodes. In this scenario, the increase in the amount of equipment can cause central node overload or single node failure. Moreover, flexible expansion requirements are difficult to achieve in such a centralized architecture. This paper proposes a safe and efficient IoT device recognition and management scheme based on blockchain and edge computing, DRMT. This scheme realizes feature extraction, clustering, and learning of IoT devices' traffic based on the characteristics of distributed deployment of edge servers. In this process, the recognition model can be continuously updated. The scheme also has an advantage that it is possible to enhance the management efficiency and scalability of the system by establishing a blockchain network between edge servers to share identification information and automate deployment security. This paper also verifies the scheme's effectiveness by building an experimental network and a blockchain system. The results showed that DRMT would help realize the effective management of large-scale IoT devices in smart cities. [ABSTRACT FROM AUTHOR]

This paper reports enhanced high-temperature piezoelectric properties of Bi(Zn0.5Ti0.5)O3-modified BiFeO3-BaTiO3 (BF–BT-xBZT) ceramics prepared by two-step sintering method. The resultant ceramics show a symmetrical transition from a rhombohedral–pseudo-cubic (R-PC) phase coexistence to main PC phase with the increase of x, whose R-PC fraction (CR/CPC) is 53.3/46.7, 52.9/47.1, 50.2/49.8, 27.4/72.6, 15.3/84.7 when x = 0, 0.005, 0.01, 0.03, 0.05, respectively. The modification of BZT inhibits the grain growth, reduces the leakage current and gradually drives ferroelectric to relaxor transition. Optimal piezoelectric properties: d33 = 193 pC N−1, Pr = 20.6 μC cm−2, TC = 503 °C and kp = 36% achieved at x = 0.01 composition, which is due to the synergistic effect of an appropriate CR/CPC ratio, improved insulation and good polarization performance. In addition, the depolarization temperature Td is close 280–312 °C, and the high-temperature d33 further increases to 286–347 pC N−1, which shows a good application prospect of lead-free piezoceramics at high temperature. Our work also confirms that the addition of (Zn0.5Ti0.5)3+ and two-step sintering method are an effective and convenient strategy to improve the high-temperature electrical performance of BiFeO3–BaTiO3 based lead-free ceramics. [ABSTRACT FROM AUTHOR]

In this article, the transient heat transfer process of the multilayer thermal protection system (TPS) doped with the phase change materials (PCM) is studied. The multilayer TPS consists of the C/SiC composite material, alumina aerogel, silica aerogel, and silica aerogel doped with the PCM. A thermal lattice Boltzmann model is adopted to consider the effect of interlayer thermal contact resistance on the transient thermal response of the TPS. An enthalpy-based lattice Boltzmann model is adopted to solve the solid–liquid phase change problem. The transient heat transfer characteristics of two kinds of TPSs in different layouts are analyzed in detail. The results show that whether the doped PCM enhances the thermal insulation performance of the TPS depends on the layout design of the multiple layers and service time. There exists an optimal layer thickness of the PCM that makes a TPS have the best thermal insulation performance, and the optimal value increases with the service time. The interlayer thermal contact resistance can have a significant effect on the transient thermal response of the TPS, and the optimal value of the PCM thickness will reduce. [ABSTRACT FROM AUTHOR]

Repeated impacts occur frequently and the damage to its structure cannot be underestimated in national defense weapons and equipment. In this article, the mechanical properties and impact behaviors of entangled metallic wire material (EMWM) with different relative densities under repeated low-velocity impacts were investigated via a series of mechanical tests. Each EMWM specimen was subjected to an impact test of 6 m/s each time, and the test was repeated ten times. Experimental results show that with the increase of the number of impact cycles, the damage of EMWM progressively intensifies, the impact stiffness increases, and the energy absorption rate decreases. The mechanical properties of EMWM with higher relative density are more stable under repeated impacts, it displays stronger repeated impact resistance, and it is suitable to withstand repeated impacts. After reaching a certain number of impact cycles, the energy absorption rate tends to be stable. The energy absorption of the EMWM mainly comes from the dry friction between the adjacent wire helixes, the plastic deformation of EMWM, and air damping. Moreover, the impact failure mechanisms of EMWM under repeated low-velocity impacts were described. The electron microscope photos show that the EMWM specimen has no obvious damage after repeated impacts, and it has good repeatable impact ability. [ABSTRACT FROM AUTHOR]

The ethanol/water separation challenge highlights the adsorption capacity/selectivity trade‐off problem. We show that the target guest can serve as a gating component of the host to block the undesired guest, giving molecular sieving effect for the adsorbent possessing large pores. Two hydrophilic/water‐stable metal azolate frameworks were designed to compare the effects of gating and pore‐opening flexibility. Large amounts (up to 28.7 mmol g−1) of ethanol with fuel‐grade (99.5 %+) and even higher purities (99.9999 %+) can be produced in a single adsorption process from not only 95 : 5 but also 10 : 90 ethanol/water mixtures. More interestingly, the pore‐opening adsorbent possessing large pore apertures showed not only high water adsorption capacity but also exceptionally high water/ethanol selectivity characteristic of molecular sieving. Computational simulations demonstrated the critical role of guest‐anchoring aperture for the guest‐dominated gating process. [ABSTRACT FROM AUTHOR]

The ethanol/water separation challenge highlights the adsorption capacity/selectivity trade‐off problem. We show that the target guest can serve as a gating component of the host to block the undesired guest, giving molecular sieving effect for the adsorbent possessing large pores. Two hydrophilic/water‐stable metal azolate frameworks were designed to compare the effects of gating and pore‐opening flexibility. Large amounts (up to 28.7 mmol g−1) of ethanol with fuel‐grade (99.5 %+) and even higher purities (99.9999 %+) can be produced in a single adsorption process from not only 95 : 5 but also 10 : 90 ethanol/water mixtures. More interestingly, the pore‐opening adsorbent possessing large pore apertures showed not only high water adsorption capacity but also exceptionally high water/ethanol selectivity characteristic of molecular sieving. Computational simulations demonstrated the critical role of guest‐anchoring aperture for the guest‐dominated gating process. [ABSTRACT FROM AUTHOR]

Summary: In this paper, an integrated coupled inductor–capacitor DC–DC high step‐up converter is proposed for the renewable energy systems. A DC–DC high step‐up converter is mandatory owing to the comparative low output voltage of renewable energy systems. A new configuration has been proposed in this paper, in which capacitor and coupled inductor are integrated into a converter to achieve the required results. To charge the capacitor a coupled inductor is used, not only the voltage gain significantly boosted and the switch voltage clamped inherently but also the turns ratio and part count scale down. When proposed converter operates in ORF mode, this results in the decline of conduction losses and enhances its efficiency. The proposed converter has good efficiency and simplest structure as it has only six components. This paper illustrates the key state operation principles of the proposed converter and derivation of its steady‐state operations. A prototype is designed, and experiments are performed in the laboratory to verify the precision of the theoretical analysis. The highest efficiency of 97% has been achieved in the laboratory. [ABSTRACT FROM AUTHOR]

The experiment was conducted to investigate the effect of different dietary crude protein levels on growth performance, serum biochemical indexes and reproductive performance of postpartum Angus cows. A total of 24 healthy and similar postpartum Angus cows with an average body weight of (480±20) kg were selected and randomly divided into three groups, with eight replicates in each group and one cow in each replicate. The cows were fed with the diets with crude protein levels of 11.78% (group I), 13.51% (group II) and 15.43% (group III), respectively. The pre-trial period was 10 d, and the formal trial period was 60 d. The results showed that there was no significant difference in initial weight and final weight among the three groups (P>0.05), the average daily gain in group II was significantly higher than that in group I and group III (P<0.05), and the feed to gain ratio significantly higher than that in group I and group III (P<0.05). The content of TP and BUN in serum in group II and group III were significantly higher than those in group I (P<0.05). The IgG content in group III was significantly higher than that in group I and group II (P<0.05). The content of IGF-1 and GH in group II were extremely higher than those in group I (P<0.01). The survival rate of calves in group II was the highest. The experiment indicates that the 13.51% crude protein level in diet can improve the growth performance, some serum biochemical indexes and reproductive performance of postpartum Angus cows under the conditions of the experiment. [ABSTRACT FROM AUTHOR]

In order to further improve the energy efficiency of power electronic systems, DC‐DC converters can increase the power density by increasing the operating frequency to reduce the size and cost. To this end, some scholars have proposed a single‐switch frequency‐doubling (SS‐FD) modulation method, which can make the working frequency of the resonant tank of the converter twice the switching frequency. However, when the full‐bridge LLC converter operates under the SS‐FD modulation, the conduction time of each switch of the same bridge arm is different, which leads to uneven heating of the switches and reduces the overall life of the device. In order to optimize this problem, this paper proposes a dual‐switches time‐sharing frequency‐doubling (DSTS‐FD) modulation. This modulation method ensures that the resonant tank works under the premise of frequency doubling, so that the heating of each switch is more balanced, thereby increasing the overall service life of the equipment. Theoretical analysis is carried out through simulation. Finally, an experimental device of 288 V and 1000 W is built. The proposed modulation method is compared with the traditional modulation method in a stable state, and the experiment verifies the superiority of the proposed modulation method. [ABSTRACT FROM AUTHOR]

Numerous important catalytic reactions, such as Fischer–Tropsch synthesis (FTS), are performed under harsh conditions in terms of high temperature of a catalyst in a mixture of reactants at a high pressure. There has been a lack of an intrinsic correlation between a catalytic performance and its corresponding catalyst structure due to the unavailable information on the authentic structure of the catalyst during catalysis under a high-temperature high-pressure (HTHP) condition. Here, we report in situ/operando studies of Co catalysts during catalysis under HTHP conditions using x-ray absorption spectroscopy (XAS). A high-temperature high-pressure catalysis-XAS (HTHP Catalysis-XAS) system using a thin, small quartz or beryllium tube as the reactor was built for in situ/operando characterization of high-energy absorption edges of 4d transition metals or low-energy absorption edges of 3d/4d transition metals under high-temperature high-pressure conditions, respectively. This reactor can be used for HTHP catalysis performed at a temperature of up to 550 °C and a gas pressure of up to 60 bars for uncovering the chemical states and coordination environments of metal atoms of these catalysts during HTHP catalysis. The capability of collecting XAS data during HTHP catalysis was confirmed through tests at 400oC in the mixture of 20 bar mixture of reactants at beamline endstation. The operando studies of Ru catalyst particles under Fischer–Tropsch catalytic conditions with extended x-ray absorption fine structure spectroscopy revealed a restructuring of the Ru catalyst at 250 °C in the mixture of 6 bars CO and 12 bars H2 during FTS (30 ml/min), which was not observed at 300 °C in 1 bar H2 (20 ml/min). This observation suggests new chemistry for metal catalysts under HTHP condition inaccessible due to a lack of applicable characterizations. These tests confirmed the function of this HTHP Catalysis-XAS system for in situ/operando characterizations of catalysts during HTHP catalysis. [ABSTRACT FROM AUTHOR]