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Accurate astrometric parameters and photometric data in three bands for more than 1.3 billion sources (mainly stars) were made available in the recent Gaia Data Release 2, allowing us to find new open clusters in the milky Way. We propose a novel sample-based clustering search method with high spatial resolution to search for open clusters (OCs). We used the proposed method to find 16 new OC candidates. Their astrometric parameters are presented, including age, etc. [ABSTRACT FROM AUTHOR]

Encapsulation of TiO 2 nanobelts into crystalline and porous covalent organic frameworks materials to form a core-shell structure can enhance reactivity, selectivity and durability of photocatalysts distinctly. In this work, a range of TiO 2 nanobelts@COF nanocomposites with different thicknesses of COF shell were fabricated via a novel and facile seed growth method. The results of photooxidation of benzyl alcohol under visible light (> 420 nm) showed that TiO 2 @COF-3 with COF shell thickness of around 15 nm showed the highest conversion (92.5%) with the maximum rate constant (6.73 × 10−2 h−1), which is approximately 10.1 times as that of TiO 2 and 12.9 times as that of COF. The enhanced photocatalytic activity of hybrid materials was mainly owing to the improved photon adsorption ability and charge carriers transfer from COF to TiO 2. In addition, TiO 2 @COF-3 still showed relatively high stability after 5 cycles under the same reaction condition. Therefore, this type of hybrid photocatalysts possesses great potentials in future green organic synthesis. • Core-shell TiO 2 @COF hybrids are synthesized by a seed growth method. • The COFs materials show as an excellent light-harvest materials. • The covalent-bond connection promotes the charge-carrier transfer and separation. • TiO 2 @COF-3 shows high activity and stability in photooxidation of aromatic alcohols. • TiO 2 @COF hybrids are firstly applied to the photooxidation of aromatic alcohol. [ABSTRACT FROM AUTHOR]

Nonlinear stiffness composite helical spring has gained considerable attention due to its significant lightweight effect and reliable nonlinear stiffness function. Those performance of helical spring is of great significance to the energy saving and comfort improvement of automobiles. In this paper, the design method of nonlinear stiffness composite helical spring using typical materials and ply scheme was put forward. The FEM models of different ply schemes were established. Combined with ABAQUS software and the secondary development subroutine, the strength and fatigue simulation analysis of circular tubes with typical ply schemes was carried out. Then the samples using different ply schemes were prepared. The failure type, stiffness attenuation rate, and height attenuation rate of springs were obtained through the strength test under extreme condition (compression state) and the fatigue test under the full-load condition. Finally, the best ply scheme and typical damage types were obtained. Comparing the test results with the simulation results, a method that can accurately predict the strength and fatigue failure of the nonlinear stiffness composite helical spring was verified. This study can provide a systematic ply scheme design method for the fatigue reliability design of composite structures with circular tube shape. [ABSTRACT FROM AUTHOR]

• A kind of effective acidic polymeric ionic liquid was developed for ethylene hydroesterification. • The crucial role of hydrogen bond in ethylene hydroesterification was identified. • The detailed mechanism of ethylene hydroesterification was proposed using in - situ spectroscopic characterization. • The kinetic behavior of ethylene hydroesterification was revealed. Hydroesterification of ethylene with carbon monoxide (CO) and methanol (MeOH) for preparing methyl propionate (MP) has stimulated researcher's attention in recent years. Herein, the palladium-phosphine catalyzed ethylene hydroesterification with the promotion of acidic poly ionic liquids (APILs) for direct MP synthesis was developed. Series of APILs samples having different anions and acid densities were prepared and their structural properties were characterized by employing NMR, FTIR, TG and XPS. The anion type and acid density in APILs shown great influence on the catalytic performance due to the electronic effect and proton supply capacity related to Pd-H species formation. The hydrogen bond formed through the interaction between the anion of APILs and methanol could effectively promote the ethylene hydroesterification. The substrate extension experiments revealed the polarity and steric hindrance of alcohol would impact ethylene conversion. The mechanistic studies using in-situ diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS) unraveled that the hydroesterification started with the activation of palladium complex to Pd-H species by CO, followed by the sequential formation of Pd-C 2 H 4 , Pd-alkyl and Pd-acyl intermediate species and consequential product MP. As a result, 94.4 % ethylene conversion could be achieved with 100 % selectivity toward MP at 80 °C and 2 MPa. No obvious deactivation behavior was observed for this kind of palladium catalyst after ten recycling experiments. The kinetic studies revealed the activation energy of ethylene hydroesterification is 59.3 kJ/mol. [ABSTRACT FROM AUTHOR]

Hematite is an excellent catalyst for solar water splitting but its practical performance is still low. In this work, a hetero phase of β-Fe 2 O 3 was firstly introduced in α-Fe 2 O 3 to optimize the internal structure, which can synergistically work with oxygen vacancy to enhance the charge extraction, facilitate the charge transport, and suppress the electron-hole recombination. As a result, the obtained hematite exhibits a high initial photocurrent of 2.72 mA/cm2 at 1.23 V vs. RHE, and can be well coupled with various further modifications such as P, Hf, and FeNiOOH to achieve an excellent photocurrent of 5.24 mA/cm2 at 1.23 V vs. RHE with a good stability over 100 h. Moreover, it can realize a benchmark solar-to-hydrogen conversion efficiency of 5.3% when connected to a commercial Si solar cell. The low cost, efficient, and stable hematite-based photoanodes may pave the way for practical solar water splitting. [Display omitted] • β-Fe 2 O 3 in hematite has been firstly reported to improve the PEC performance. • Hetero phase and oxygen vacancy can effectively enhance the bulk charge utilization. • It can achieve a high and stable photocurrent of 5.24 mA/cm2 at 1.23 V RHE. • A benchmark solar-to-hydrogen conversion efficiency of 5.3% can be obtained. [ABSTRACT FROM AUTHOR]

MOF-derived XMn 2 O 4 (X = Zn, Co, Cu, Ni) nanomaterials achieve superior electrochemical performance for lithium storage. [Display omitted] • Two methods are proposed for the synthesis of XMn 2 O 4 (X = Zn, Co, Cu, Ni). • MOF-derived anodes exhibit excellent electrochemical capabilities compared with the ones obtained by simple coprecipitation. • Lithium storage capacity and rate performance of XMn 2 O 4 is best when X = Zn. • DFT calculations are performed to demonstrate that ZnMn 2 O 4 as an anode material is conducive to the diffusion of Li+. Bimetallic spinel transition metal oxides play a major part in actualizing eco-friendly electrochemical energy storage systems (ESSs). However, structural precariousness and low electrochemical capacitance restrict their actual implementation in lithium-ion batteries (LIBs). To address these demerits, the sacrificial template approach has been considered as a prospective way to strengthen electrochemical stability and rate performance. Herein, metal-organic frameworks (MOFs) derived XMn 2 O 4 -BDC (H 2 BDC = 1,4-dicarboxybenzene, X = Zn, Co, Cu, Ni) are prepared by a hydrothermal approach in order to discover the effects of various metal cations on the electrochemical performance. Among them, ZnMn 2 O 4 -BDC displays best electrochemical properties (1321.5 mAh g−1 at the current density of 0.1 A g−1 after 300 cycles) and high efficiency with accelerated Li+ diffusivity. Density functional theory (DFT) calculations confirm the ZnMn 2 O 4 possesses the weakest adsorption energy on Li+ with a minimized value of −0.92 eV. In comparison with other XMn 2 O 4 through traditional fabrication method, MOF-derived XMn 2 O 4 -BDC possesses a higher number of Li+ transport channels and better electric conductivity. This tactic provides a feasible and effective method for preparing bimetallic transition metal oxides and enhances energy storage applications. [ABSTRACT FROM AUTHOR]

Highlights • Extract's main basic constituent responsible for inhibition is Glu, Pro and Leu. • MGME and its main basic constituent are mixed-type inhibitors. • The antagonistic effect between Glu, Pro and Leu in extract was investigated. • Bonding of main basic inhibitors with steel was studied by theoretical calculation. Abstract The inhibition mechanism of maize gluten meal extract (MGME) for steel was systematically elucidated combining experimental analysis with theoretical calculation. It is revealed that the MGME and its main basic constituent are responsible for inhibition including Glu, Pro and Leu, their inhibition efficiency are 83.15% and 79.27%, respectively. The antagonistic effect between the main basic molecules of Glu, Pro and Leu in MGME and the barrier film formed on steel surface were verified by electrochemical measurement and XPS result, respectively. Besides the quantum chemical calculation and Monte Carlo simulation were used to clarify inhibition mechanism of co-adsorption. [ABSTRACT FROM AUTHOR]

Abstract Temporary structures, which are designed to be quickly erected and in service for short periods of time, are widely used in performances and sports competitions. This temporary characteristic requires special construction to be implemented. This paper presents a new modular support structure that can be used as temporary grandstands, stages, ski runs and disaster relief rooms. This modular support structure is composed of the foldable plane frame with corresponding joints. The assembly property is achieved through joint connection among these frames. The local folding characteristic of these plane frames improves both erection and transportation efficiency. As a core component of this modular support structure, the aluminum alloy assembly column was particularly concerned and the axial stability of the column was investigated experimentally. The results indicated that the use of the connection ring could improve the stability of the assembly column along with the connections between the foldable plane frames. Numerical analysis of the tested specimens under axial compression was developed. The ultimate strength, failure modes and load-displacement curves obtained from the numerical results agreed well with the test results. Equivalent stability factors of the assembly columns were calculated to further illustrate axial stability of the column. Graphical abstract fx1 Highlights • A new modular support structure used to build the temporary structure is presented. • The stability of the aluminum alloy assembly column is studied experimentally. • Numerical models of the aluminum alloy assembly column are developed. • Equivalent stability factors of the aluminum alloy assembly columns are calculated. [ABSTRACT FROM AUTHOR]

Abstract This paper investigates the lateral performance of temporary structures, which consist of slender members and corresponding joints, under both vertical and horizontal loads. The ultimate bearing capacity, failure modes and the strain distribution of members are illustrated. Experimental results indicate that the lateral stability of the temporary structures is weaker than the vertical stability. Diagonal bracings are the main load-bearing members which resist horizontal loads while the horizontal bars are used to keep stress low. Based on the joint mechanical parameters and the probabilistic models of initial geometric imperfection, the stochastic finite element models (SFEMs) using the Monte Carlo method have been established. The models can consider the semi-rigid performances of joints and initial geometric imperfection. The numerical results demonstrate consistency with structural tests data. Moreover, the influences of structural layers and spans are analysed based on the SFEM. Multiple factors, including spans, layers and upper vertical loads, should be considered when the lateral capacity of temporary structures is calculated. A rapid prediction formula of the lateral stability of temporary structure has been obtained. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19) threatens public health all over the world. It is well-accepted that the immune cells in peripheral blood are widely involved in the pathological process of COVID-19. However, hematopoietic stem and progenitor cells (HSPCs), as the main source of peripheral immune cells, have not been well studied during COVID-19 infection. We comprehensively revealed the transcriptome changes of peripheral blood HSPCs after COVID-19 infection and vaccination by single-cell RNA-seq. Compared with healthy individuals, the proportion of HSPCs in COVID-19 patients significantly increased. The increase in the proportion of HSPCs might be partly attributed to the enhancement of the HSPCs proliferation upon COVID-19 infection. However, the stemness damage of HSPCs is reflected by the decrease of differentiation signal, which can be used as a potential specific indicator of the severity and duration of COVID-19 infection. Type I interferon (IFN-I) and translation signals in HSPCs were mostly activated and inhibited after COVID-19 infection, respectively. In addition, the response of COVID-19 vaccination to the body is mild, while the secondary vaccination strengthens the immune response of primary vaccination. In conclusion, our study provides new insights into understanding the immune mechanism of COVID-19 infection. [ABSTRACT FROM AUTHOR]

Dedicated equipment, which is widely used in many different types of vehicles, is the core system that determines the combat capability of special vehicles. Therefore, assuring the normal operation of dedicated equipment is crucial. With the increase in battlefield complexity, the demand for equipment functions is increasing, and the complexity of dedicated equipment is also increasing. To solve the problem of fault diagnosis of dedicated equipment, a fault diagnosis algorithm based on CNN-LSTM was proposed in this paper. CNN and LSTM are used in the model adopted by the algorithm to extract spatial and temporal features from the data. CBAM is used to enhance the model's accuracy in identifying faults for dedicated equipment. Data on dedicated equipment faults were obtained from a hardware-in-loop simulation platform to verify the model. It is demonstrated that the proposed fault diagnosis algorithm has high recognition ability for dedicated equipment by comparing it to other neural network models. [ABSTRACT FROM AUTHOR]

Oily sludge, as a critical hazardous waste, requires appropriate treatment for resource recovery and harmfulness reduction. Here, fast microwave-assisted pyrolysis (MAP) of oily sludge was conducted for oil removal and fuel production. The results indicated the priority of the fast MAP compared with the MAP under premixing mode, with the oil content in solid residues after pyrolysis reaching below 0.2%. The effects of pyrolysis temperature and time on product distribution and compositions were examined. In addition, pyrolysis kinetics can be well described using the Kissinger-Akahira-Sunose (KAS) and the Flynn-Wall-Ozawa (FWO) methods, with the activation energy being 169.7–319.1 kJ/mol in the feedstock conversional fraction range of 0.2–0.7. Subsequently, the pyrolysis residues were further treated by thermal plasma vitrification to immobilize the existing heavy metals. The amorphous phase and the glassy matrix were formed in the molten slags, resulting in bonding and, hence, immobilization of heavy metals. Operating parameters, including working current and melting time, were optimized to reduce the leaching concentrations of heavy metals, as well as to decrease their volatilization during vitrification. [ABSTRACT FROM AUTHOR]

With technology scaling down, scale of the integrated circuit (IC) increases rapidly. It is unrealistic to harden every element in the IC, hence it is critical to evaluate relative single-event transient (SET) or single-event upset (SEU) sensitivity of each node in the IC to selectively harden the elements connected to the identified highly sensitive nodes. Therefore, this paper proposes a test circuit to measure the relative SET/SEU sensitivity of each node in any circuit working in real time. This will have significant implications for designing ICs with high reliability and low overheads. [ABSTRACT FROM PUBLISHER]

In this paper, tests of plug-pin joints are conducted in order to obtain their mechanical parameters, including semi-rigid property. To solve the difficulties of multi-point displacement measurements for small joints, this investigation proposes a visionbased measurement system based on the principle of binocular stereo vision to improve measurement accuracy. Accurate subpixel location is achieved according to a template-matching algorithm based on grayscale. Joint performance, including horizontal bar joint tension and compression, semi-rigidity between horizontal bars and upright rods and bracing tension and compression, is investigated in order to acquire joint failure modes as well as load and displacement (or moment and rotation angle) curves. Through data fitting, multi-linear simplified models are proposed to illustrate the joints' mechanical performance. This paper also investigates geometric imperfection of temporary member structure with plug-pin joints based on several substructure models and temporary grandstand units using a total station theodolite. The probabilistic models of initial member out-of-straightness and story frame out-of-plumb have been acquired, which can be used into Monte Carlo simulation to create stochastic model of the temporary member structure. [ABSTRACT FROM AUTHOR]

High-mix fly ash (FA) is often used in roller compacted concrete (RCC) to ensure construction quality and reduce project cost. However, cost and difficulty of schedule control will increase if FA is transferred from other areas because the resource is relatively scarce in Tibet of China. Based on the richness of tuff resources at the Daigo hydropower station in Tibet, studying the feasibility of concrete application with tuff powder as the admixture is necessary because of the low cost and small impact on schedule. Research compared the performance indicators of RCC of tuff concrete (concrete mixed with only tuff powder), FA concrete (concrete mixed with only FA) and concrete mixed with FA and tuff. The results showed the tuff concrete increased the earlier compressive strength, earlier tensile strength and the drying shrinkage ratio and reduced the impermeability and frost resistance in freeze-thaw cycles. The tuff concrete performed well against cracks and deformation in comparison with the FA concrete and can meet the design requirements of the Daigo hydropower station. The results provide data for the selection of concrete mixtures for the Daigo hydropower stations. [ABSTRACT FROM AUTHOR]

Developing efficient non-noble metal and earth-abundant electrocatalysts with tunable microstructures for overall water splitting is critical to promote clean energy technologies for a hydrogen economy. Herein, novel three-dimensional (3D) flower-like Ni2P composed of mesoporous nanoplates with controllable morphology and high surface area was prepared by a hydrothermal method and low-temperature phosphidation as efficient electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Compared with the urchin-like Ni xP y, the 3D flower-like Ni2P with a diameter of 5 μm presented an efficient and stable catalytic performance in 0.5 m H2SO4, with a small Tafel slope of 79 mV dec−1 and an overpotential of about 240 mV at a current density of 10 mA cm−2 with a mass loading density of 0.283 mg cm−2. In addition, the catalyst also exhibited a remarkable performance for the OER in 1.0 m KOH electrolyte, with an overpotential of 320 mV to reach a current density of 10 mA cm−2 and a small Tafel slope of 72 mV dec−1. The excellent catalytic performance of the as-prepared Ni2P may be ascribed to its novel 3D morphology with unique mesoporous structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • A double-layer coating strategy is used to enhance the performance of SiO x anode. • The dual-shell structure consists of an Sn inner layer and N-doped outer layer. • The inner Sn can improve electronic conductivity and charge transfer kinetics. • The outer N-doped carbon shell can further maintain the structural integrity. • The dual-shell SiO x /C@Sn@NC anode exhibits excellent lithium storage ability. SiO x -based anode materials (0 < x < 2) have been regarded as an appealing candidate for anode material of commercial Lithium-ion batteries accounting for their ultrahigh theoretical capacity and low cost. However, its large-scale applications have been hampered by the serious volume expansion during repeated cycles, low intrinsic conductivity and unsatisfactory initial Coulombic efficiencies. Herein, to address these inherent deficiencies, a hierarchical SiO x -based anode with double-layer coatings of Sn inner layer and N-doped carbon outer shell is elaborately designed by a facile two-step hydrolysis process and polymer coating technology. Benefiting from the "synergistic effect" between Sn and SiO x at different working potentials and a well-designed double-layer coating structure, the resultant SiO x /C@Sn@NC anode displays excellent electrochemical properties, including an enhanced initial Coulomb efficiency (73.3%) efficiency, higher reversible capacity (991 mAh g−1) and superior long lifespan. Moreover, comprehensive characterization based on the reaction kinetics and structural stability proved that such enhanced ICE and cycling stability of anode material stem from its unique double-layer coating structure and multiple active components, which can significantly improve the diffusion of ion and charge transport, stabilize solid-electrolyte interphase (SEI) layer and absorb the expansion stress of electrode. Therefore, this study provides an efficient and feasible strategy to overcome the limitations of high-capacity SiO x -based anode materials via hybridization design with various active components and a double-layer coating strategy. [ABSTRACT FROM AUTHOR]

• The delamination behavior of CNTs with different contents in PW and UD fabric composites is investigated. • The initial and propagation fracture toughness are calculated through the modified beam theory. • The acoustic emission signals of different damage mechanisms are distinguished. • The weakening and enhancing mechanisms are revealed by observing the surface photomicrograph. This paper investigates the delamination behavior of two composite structures with carbon nanotubes (CNTs). Double cantilever beam (DCB) samples with CNTs of different areal densities are adopted to analyze the toughening and damage mechanism via acoustic emission (AE) method. The result demonstrates that the CNT layer improves the fracture toughness of unidirectional (UD) sample interfaces effectively, but for the plain woven (PW) samples, only works on initial fracture toughness with low CNTs areal density. In addition, more AE events are recorded in the CNT modified samples than in the reference sample. Combined with the observation of the fracture surface and crack propagation path, the agglomeration with high content CNTs weakens the interlayer strength in PW samples, whereas the fracture toughness is significantly enhanced in UD composites due to the increase of the crack propagation path. [ABSTRACT FROM AUTHOR]

Ultrasonic testing (UT) is commonly used to inspect the geometric shape of internal damage in composite materials and the test results need to be interpreted by trained experts. In this work, an automatic signal classification method based on deep learning is proposed for depth estimation of the detects introduced by low-velocity impact (LVI) in carbon fiber reinforced plastics (CFRPs). Three kinds of neural networks, LSTM, CNN, and CNN-LSTM are used to analyze the attributes with different depths. Then, trained models are applied to identify the depth information of impact damage. The results show that the CNN-LSTM model is a more accurate in-depth classification for LVI defects in CFRP based on A-scan signals than the other two structures. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is a leading cause of vision impairment and blindness among diabetics. We aimed to explore whether long-term exposure to residential greenness was beneficial to DR. We used data from a large-scale, cross-sectional screening survey conducted in 129 cities of 27 provincial regions of China from 2018 to 2021 among patients with diabetes. We measured residential greenness exposure as the 3-year average of annual maximum Normalized Difference Vegetation Index (NDVI) at a spatial resolution of 250 m. DR was assessed by ophthalmologists based on fundus photographs. The primary outcome was DR, and secondary outcome included DR severity status (i.e., nonproliferative and proliferative), hallmarks of retinal lesions and macular oedema. A total of 484,380 adult participants with diabetes were included in the current analysis, and 15.7% of them were diagnosed with DR. NDVI was inversely and linearly associated with DR prevalence, and an increment of 0.1 NDVI was associated with a 10% (9%–10%) decrease in DR prevalence. Significant and inverse associations were further found for nonproliferative and proliferative DR, hallmarks of lesions and macular oedema. The association between greenness and DR was stronger among participants who were older, obese, lived in the south, had longer duration of diabetes or did not take antidiabetic medications. This large-scale nationwide study provides the first-hand epidemiological evidence on the associations of residential greenness with DR. Our findings highlight the importance of residential greenness in alleviating DR risk especially in an era of aging and urbanization. • The first to examine the relationship between greenness and diabetic retinopathy (DR). • Greenness exposure was almost linearly associated with decreased odds of DR. • Greenness was inversely associated with nonproliferative and proliferative DR. • Greenness was inversely associated with hallmarks of DR and macular oedema. [ABSTRACT FROM AUTHOR]

• An method of multi-source data-driven unsaturated seepage parameter inversion. • NSGA-II is used to generate the pareto-optimal solutions of parameters. • Parameter decision based on a comprehensive index composed of multi-source data. • Inversion results are more in line with engineering practice and have higher accuracy. The inverse parameter's estimation of unsaturated seepage models is important to ensure the safety of earth dams, while most existing studies determine the hydraulic characteristics only based on seepage pressure monitoring data, which may lead to inversion results deviating from the intrinsic properties of dam materials. This study proposed an advanced methodology for unsaturated seepage parameter inversion of earth dams driven by multi-source data. The transient unsaturated seepage behavior of earth dams is simulated using the Van Genuchten (VG) model, and the extreme learning machine (ELM) is adopted as the surrogate model to estimate the approximate simulation results. Then the multi-objective function for parameter inversion is constructed by combining the observed transient pressure data and ELM models, and the Pareto-optimal solutions are generated using the elitist non-dominated sorting genetic algorithm (NSGA-II). Multi-source information, including parameter design values, in-situ testing results, and monitoring data, are fused to construct a comprehensive index to drive the parameter decision. The proposed method is applied to the PB core rockfill dam, which has a well-established seepage pressure monitoring system. In addition, the design values and in-situ testing results of the hydraulic conductivity of the dam material are also available. The results showed that the inversion parameters of the proposed method are closer to the physical characteristics of materials and have advantages in prediction accuracy. [ABSTRACT FROM AUTHOR]

Based on Doppler radar observation and reanalysis data, the statistical characteristics of mesovortices (MVs) during the first rainy season (April–June) in Guangdong, South China, from 2017 to 2019 are studied, including their spatiotemporal distributions, structural features and favorable environmental conditions. The results show that the MVs usually exhibit short lifetimes; about 70% last for less than 30 min. The intensity and horizontal scale of the MVs are proportional to their lifetime. Long-lived MVs have larger horizontal scales and stronger intensities than short-lived ones. The MVs are mainly observed over the Pearl River Delta region, followed by western Guangdong Province, but relatively fewer in both eastern and northern Guangdong Province. The uneven spatial distribution of the MVs is closely related to the differences in the topographical features and the environment conditions over South China. MVs are prone to form over flat regions. The Pearl River Delta and eastern Guangdong regions are relatively flat compared to the more mountainous western and northern Guangdong regions. Moreover, the monsoonal south-westerlies, water vapor flux, atmospheric instability and vertical wind shear over southwest Guangdong are significantly larger than those in other regions and are favorable for the formation of MVs. The occurrence frequencies of MVs in central and southern parts of Guangdong display similar diurnal variations, reaching the peak during the late afternoon and early evening while dropping to the minimum overnight. However, the situation is opposite in northern Guangdong, with the peak overnight and the minimum during the late afternoon and early evening. The regional differences in diurnal variation are likely related to the moving direction of mesoscale convective systems (MCSs) in Guangdong. [ABSTRACT FROM AUTHOR]

The low crystallization rate and long molding time of poly(ethylene terephthalate) (PET) restricts its application in the field of engineering plastics. PET/graphene oxide (GO) composites were synthesized through in situ polymerization method with dimethyl terephthalate (DMT), ethylene glycol (EG) as reactants and GO as filler in order to overcome the above shortcomings. Influence of GO on the crystallization performance of PET was investigated. It was revealed GO raised the crystallization temperature and crystallization rate of PET, demonstrating the excellent nucleation capability of GO. The mechanism of PET nucleation induced by GO was investigated by Avrami equation and Hoffman-Lauritzen theory. It was obvious the crystallization behavior of PET was improved by reducing the free energy of nucleation and the fold surface free energy of PET caused by GO. Moreover, the non-isothermal kinetics of thermal decomposition of PET and PET/GO composites were studied by Friedman method. It was obvious that all of PET and PET/GO composites exhibited a fine thermal stability with no significant mass loss observed up to 370 °C (< 0.5%). The addition of GO improved the thermal stability of PET through raising the apparent activation energy, inhibiting the escape of volatile products and absorbing the degradation products in PET thermal decomposition procedure. [ABSTRACT FROM AUTHOR]

To achieve a wide range and high accuracy detection of the vacuum level, for example, in an encapsulated vacuum microcavity, a composite-type MEMS Pirani gauge has been designed and fabricated. The Pirani gauge consists of two gauges of different sizes connected in series, with one gauge having a larger heat-sensitive area and a larger air gap for extending the lower measurable limit of pressure (i.e., the high vacuum end) and the other gauge having a smaller heat-sensitive area and a smaller air gap for extending the upper measurable limit. The high-resistivity titanium metal was chosen as the thermistor; SiNx was chosen as the dielectric layer, considering the factors relevant to simulation and manufacturing. By simulation using COMSOL Multiphysics and NI Multisim, a range of measurement of 2 × 10−2 to 2 × 105 Pa and a sensitivity of 52.4 mV/lgPa were obtained in an N2 environment. The performance of the fabricated Pirani gauge was evaluated by using an in-house made vacuum test system. In the test, the actual points of measurement range from 6.6 × 10−2 to 1.12 × 105 Pa, and the highest sensitivity is up to 457.6 mV/lgPa. The experimental results are better in the range of measurement, sensitivity, and accuracy than the simulation results. The Pirani gauge proposed in this study is simple in structure, easy to manufacture, and suitable for integration with other MEMS devices in a microcavity to monitor the vacuum level therein. [ABSTRACT FROM AUTHOR]

The effect of axial yarns on progressive bending damage of braided composite tubes is studied in this paper. Four specimens with different number and distribution of axial yarns were experimentally tested by quasi-static three-point bending. At the same time, infrared thermography was used to observe the damage in-situ. Combined with the cross-section morphology of Ultra-Depth 3D Microscope, the damage evolution and distribution characteristics of braided tubes were identified. It is found that axial yarns enhance the mechanical properties of braided composite tube. The detected changes of infrared maximum temperature have a good correlation with the damage initiation and failure mechanism of the specimen. The abrupt changes of the maximum temperature indicate the occurrence of local fiber breakage, especially the axial yarn breakage. If there are axial yarns on the compression side of the tube, the maximum temperature increases by 0.5 °C in the linear elastic stage, and two initial damages of debonding and fiber breakage will occur. The debonding started at the interface of the axial yarn. The axial yarns increased fiber crimp, resulting in obvious wavy delamination between layers of the specimen, and the axial damage range was expanded. In addition, the mixed structure with axial yarns only on the compression side can inhibit the damage from spreading down the braided tube wall. • The progressive bending damage of triaxial braided tube was studied. • The abrupt change of infrared maximum temperature indicates local fiber breakage. • The mixed structure with axial yarns only in the upper half can inhibit damage spreading downward. [ABSTRACT FROM AUTHOR]

We present a new magnetometry method integrating an ensemble of nitrogen-vacancy (NV) centers in a single-crystal diamond with an extended dynamic range for monitoring a fast changing magnetic-field. The NV-center spin resonance frequency is tracked using a closed-loop frequency locked technique with fast frequency hopping to achieve a 10 kHz measurement bandwidth, thus allowing for the detection of fast changing magnetic signals up to 0.723 T/s. This technique exhibits an extended dynamic range subjected to the working bandwidth of the microwave source. This extended dynamic range can reach up to 4.3 mT, which is 86 times broader than the intrinsic dynamic range. The essential components for NV spin control and signal processing, such as signal generation, microwave frequency control, data processing, and readout, are integrated in a board-level system. With this platform, we demonstrate a broadband magnetometry with an optimized sensitivity of 4.2 nT Hz−1/2. This magnetometry method has the potential to be implemented in a multichannel frequency locked vector magnetometer suitable for a wide range of practical applications, such as magnetocardiography and high-precision current sensors. [ABSTRACT FROM AUTHOR]

Introduction: Due to its progressive nature, early evaluation and timely prediction of legal blindness are important in patients with neovascular age-related macular degeneration (nAMD). We examined the association between early-stage variation in central retinal thickness (CRT) and long-term visual outcomes in patients with nAMD. Methods: We included 103 nAMD patients who were administered anti-vascular endothelial growth factor (anti-VEGF). Participants were considered qualified if they were (1) 50 years and older, (2) treatment-naïve, (3) received standard anti-VEGF treatment and had complete baseline information. We further excluded patients with less than 1-year follow-up data and those who experienced best corrected visual acuity ≤35. Early-stage variability in CRT was measured as the first-year coefficient of variability (CV) of CRT. Patients were then classified into the high-variability and low-variability groups according to the X-tile. A product-limit plot was used to demonstrate the differences and tested with the log-rank test. The association between first-year variability and visual outcomes was quantified using Cox regression models. Time-to-event primary endpoint was the overall visual preservation (OVP) rate, defined as the time from the first injection to legal blindness, i.e., best corrected visual acuity ≤35 Early Treatment Diabetic Retinopathy Study (ETDRS) letters. Results: A threshold of 20% of first-year CV in CRT was used to categorize 76 qualified patients into high variability (35, 46.1%) and low variability (41, 53.9%). The 5- and 10-year OVPs for patients with high versus low variability were 76% versus 48% and 59% versus 22%, respectively. High early-stage CRT variability showed a significantly higher risk of legal blindness. Even after adjusting for the demographic and clinical features, the variability remained significant (HR = 2.39, 95% CI: 1.20–4.78). Conclusion: First-year variability of CRT was predictive of long-term visual outcomes in patients with nAMD, and 20% of the variability could be used as a clinically convenient threshold to qualitatively classify patients into high- and low-variability groups. The current study is important for identifying high-risk populations and for long-term disease management. [ABSTRACT FROM AUTHOR]

Introduction: Previous studies have explored prediction value of serum metabolites in neoadjuvant chemoradiation therapy (NCRT) response for rectal cancer. To date, limited literature is available for serum metabolome changes dynamically through NCRT. Objectives: This study aimed to explore temporal change pattern of serum metabolites during NCRT, and potential metabolic biomarkers to predict the pathological response to NCRT in locally advanced rectal cancer (LARC) patients. Methods: Based on dynamic UHPLC-QTOF-MS untargeted metabolomics design, this study included 106 LARC patients treated with NCRT. Biological samples of the enrolled patients were collected in five consecutive time-points. Untargeted metabolomics was used to profile serum metabolic signatures from LARC patients. Then, we used fuzzy C-means clustering (FCM) to explore temporal change patterns in metabolites cluster and identify monotonously changing metabolites during NCRT. Repeated measure analysis of variance (RM-ANOVA) and multilevel partial least-squares discriminant analysis (ML-PLS-DA) were performed to select metabolic biomarkers. Finally, a panel of dynamic differential metabolites was used to build logistic regression prediction models. Results: Metabolite profiles showed a clearly tendency of separation between different follow-up panels. We identified two clusters of 155 serum metabolites with monotonously changing patterns during NCRT (74 decreased metabolites and 81 increased metabolites). Using RM-ANOVA and ML-PLS-DA, 8 metabolites (L-Norleucine, Betaine, Hypoxanthine, Acetylcholine, 1-Hexadecanoyl-sn-glycero-3-phosphocholine, Glycerophosphocholine, Alpha-ketoisovaleric acid, N-Acetyl-L-alanine) were further identified as dynamic differential biomarkers for predicting NCRT sensitivity. The area under the ROC curve (AUC) of prediction model combined with the baseline measurement was 0.54 (95%CI = 0.43 ~ 0.65). By incorporating the variability indexes of 8 dynamic differential metabolites, the prediction model showed better discrimination performance than baseline measurement, with AUC = 0.67 (95%CI 0.57 ~ 0.77), 0.64 (0.53 ~ 0.75), 0.60 (0.50 ~ 0.71), and 0.56 (0.45 ~ 0.67) for the variability index of difference, linear slope, ratio, and standard deviation, respectively. Conclusion: This study identified eight metabolites as dynamic differential biomarkers to discriminate NCRT-sensitive and resistant patients. The changes of metabolite level during NCRT show better performance in predicting NCRT sensitivity. These findings highlight the clinical significance of metabolites variabilities in metabolomics analysis. [ABSTRACT FROM AUTHOR]

Objective: To investigate whether peritoneal disease extent can predict the survival benefit of intraperitoneal/intravenous (IP/IV) chemotherapy in ovarian cancer. Design: A treatment‐free survival (TFS) analysis. Setting: Five‐centre trial. Population: An extended follow‐up of the Additional Intraperitoneal Cisplatin and Etoposide in ovarian cancer (AICE) trial (NCT01669226), with data cut‐off on 27 August 2020. Patients were categorised into subgroups with high tumour burden (HTB) and low tumour burden (LTB). Methods: Overall survival (OS) was divided into time on protocol treatment exposure (T), time free of subsequent treatment or death (TFS) and time after the first subsequent therapy (REL). TFS analyses and quality‐adjusted OS were calculated by multiplying the mean time in each health state by its assigned utility: quality‐adjusted OS = ut × T + TFS + urel × REL. Main outcome measures: The area under each Kaplan–Meier curve was estimated using the 96‐month restricted mean time, with threshold utility analyses used to illustrate quality‐adjusted OS comparisons. Results: In the HTB subgroup, the restricted mean TFS was 33.9 months and 18.7 months in the IP/IV and IV groups, respectively (p = 0.005), with a significant quality‐adjusted OS gain (13.2–16.0 months). In the LTB subgroup, IP/IV therapy yielded no survival benefit in either TFS (p = 0.268) or quality‐adjusted OS (range: 1.4–6.3 months). Conclusions: Both TFS and quality‐adjusted OS was longer across all utility weight values with IP/IV than with standard IV therapy in the HTB subgroup, whereas patients in the LTB subgroup did not benefit from the therapy. The tumour burden of ovarian cancer should be assessed before deciding on IP/IV versus IV treatment. [ABSTRACT FROM AUTHOR]

Triaxial braided composites employed as structural components need to be drilled for mechanical connections. This study is to investigate the thrust force, temperature elevation, and drilling-induced damages with varying machining parameters in the drilling of triaxial braided CFRP. A high-resolution infrared thermography was carried out to capture the temperature of the panel side surface and the drill-exit surface of CFRP. The damage characteristic of drilled hole was evaluated, and a relationship between force, temperature, and hole damage was established. The obtained results indicate that the temperature of triaxial braided CFRP was mainly transferred along the fiber direction. The temperature isothermal at the drill-exit surface developed from polygonal to roughly circular with the increase of drilling depth. The braided yarns tended to deflect, and induced poorly cut fibers due to the more heat generation with the low feed, making the matrix behaved from brittle to ductile and therefore resulting in more burrs. The increase of spindle speed could restrain the burrs. A larger thrust force with high feed will result in fiber-resin debonding and more tearing defects. The delamination occurred at the interface of fiber bundles at the outermost layer with high thrust force and cracks propagated along the yarn direction. [ABSTRACT FROM AUTHOR]

A constrained interval optimization model is proposed for the optimization of uncertain structures with their mechanical performance indices described as the objective and constraint functions of the design vector and interval uncertain parameters. Present indirect approaches for solving such interval optimization models by converting them into deterministic ones will result in the loss of uncertainty information and deviate from the original intention of realistically modeling engineering optimization problems. To overcome these shortcomings, a novel optimization algorithm is proposed for directly solving the nonlinear constrained interval optimization models based on a novel concept of the degree of interval constraint violation (DICV) and the DICV-based preferential guidelines. A nested genetic algorithm (GA) is developed to realize the direct interval ranking of various design vectors. The outer layer GA locates the optimal solution based on direct interval ranking. The inner layer GAs integrated with Kriging technique compute the intervals of the mechanical performance indices of every design vector in the current population of the outer layer GA. The validity and superiority of the proposed direct interval optimization algorithm was verified by three numerical examples. Finally, the proposed direct interval optimization method was applied to the optimization of the cone ring fixture with uncertain material properties in a large turbo generator aimed at moving its natural frequencies away from the exciting one. The results demonstrated its feasibility and effectiveness in optimizing practical engineering structures under uncertainties. [ABSTRACT FROM AUTHOR]

Deep brain stimulation (DBS) has improved the prospects for many individuals with diseases affecting motor control, and recently it has shown promise for improving cognitive function as well. Several studies in individuals with Alzheimer disease and in amnesic rats have demonstrated that DBS targeted to the fimbria-fornix, the region that appears to regulate hippocampal activity, can mitigate defects in hippocampus-dependent memory. Despite these promising results, DBS has not been tested for its ability to improve cognition in any childhood intellectual disability disorder. Such disorders are a pressing concern: they affect as much as 3% of the population and involve hundreds of different genes. We proposed that stimulating the neural circuits that underlie learning and memory might provide a more promising route to treating these otherwise intractable disorders than seeking to adjust levels of one molecule at a time. We therefore studied the effects of forniceal DBS in a well-characterized mouse model of Rett syndrome (RTT), which is a leading cause of intellectual disability in females. Caused by mutations that impair the function of MeCP2 (ref. 6), RTT appears by the second year of life in humans, causing profound impairment in cognitive, motor and social skills, along with an array of neurological features. RTT mice, which reproduce the broad phenotype of this disorder, also show clear deficits in hippocampus-dependent learning and memory and hippocampal synaptic plasticity. Here we show that forniceal DBS in RTT mice rescues contextual fear memory as well as spatial learning and memory. In parallel, forniceal DBS restores in vivo hippocampal long-term potentiation and hippocampal neurogenesis. These results indicate that forniceal DBS might mitigate cognitive dysfunction in RTT. [ABSTRACT FROM AUTHOR]

Numerical simulation is a key means to evaluate the forming performance of 3D woven preforms (3DWPs). However, the macroscopic continuous model of 3DWPs cannot predict the orientation and deformation of yarns, while the microscopic discrete model is unsuitable for large-size samples forming simulation due to computational constraints. A novel mesoscopic hybrid element yarn model is thus proposed to establish a large-size 3D woven virtual yarn preform (VYP) model and the L-shaped virtual forming simulation model. The L-shaped forming experiment of the 3DWP is designed and executed, and the accuracy of the numerical simulation models is verified from three aspects: the mechanical curve, the sample's macroscopic morphology, and the local meso -structure features. Subsequently, the deformation behavior of the yarn structure inside the 3DWP during the L-shaped forming process is analyzed by combining experimental and simulation results. Furthermore, the effects of the L-shaped angle and chamfer radius on the deformation behavior of the 3DWP are studied, which helps guide the structural design of 3DWPs. [ABSTRACT FROM AUTHOR]

• GLNSYMnO 3 has a single-phase orthorhombic perovskite structure sintered at 1250 °C. • The high configurational entropy drives the structural stability of GLNSYMnO 3 even at temperatures below T C. • GLNSYMnO 3 has good magnetism due to the lattice distortion and double-exchange. • GLNSYMnO 3 is a second-order magnetic phase transition material with potential applications in magnetic storage. Rare-earth transition element high-entropy perovskite ceramics (HEPCs) (Gd 0.2 La 0.2 Nd 0.2 Sm 0.2 Y 0.2)MnO 3 (GLNSYMnO 3) were prepared by using a solid-state reaction method, and the structure, morphology and magnetic properties of the GLNSYMnO 3 were studied. The crystalline structure of GLNSYMnO 3 is a smooth surface and similar to "cashews" tubular particles, and a single-phase orthorhombic (Pbnm Space group) perovskite without impurities is confirmed when the sintered temperature reaches or exceeds 1250 °C by the analysis of phase composition and microstructures. Magnetic measurements indicate that GLNSYMnO 3 HEPCs have low Curie temperature (T C = 61 K), but they exhibit a good magnetism by comparison with other high-entropy ceramics, which is caused by the lattice distortion and exchange interactions between high concentrations of Mn3+ (92.4 %) and non-magnetic oxygen ions, promoting the movement of circulating electrons. GLNSYMnO 3 HEPCs did not undergo a phase transition below T C due to high configurational entropy driving structural stability. In addition, GLNSYMnO 3 HEPCs undergo a second-order magnetic phase transition from isothermal magnetization curves and Arrot curves, which have potential applications in magnetic storage. [ABSTRACT FROM AUTHOR]

I-section carbon fiber reinforced polymer (I-CFRP) laminates are widely used as hatch and cargo doors of wide-body airliners. However, estimating the loading capacity of I-CFRP laminates has always been empirically dependent since there is no uniform failure criterion for composite materials. This study attempts to reveal the failure characteristic points of I-CFRP laminates from a thermodynamic perspective. First, the test strain data can be modeled as state variables, thus equating the loaded engineering structure to a thermodynamic system. Based on the relation of state variables, matrices (Modes) and Hamiltonians (Characteristic parameters) that characterize the overall stressing state evolution of the specimen can be established. Integrating the Hamiltonians of each part into the whole is similar to the group representation and renormalization of Wilson's phase transition theory. Applying the clustering analysis (CA) criterion in combination with the bifurcation and transition of the mode and characteristic parameter curves reveals the phase transformation loads of the specimen. The accuracy and stability can be verified for the phase transition loads before and after the renormalization transformation. In conclusion, this study reveals the deformation-failure law of I-CFRP laminates from the thermodynamic perspective, which provides a new reference and method for the design of composite laminates. [Display omitted] • Eleven I-CFRP laminates axial compression tests were conducted. • Modeling the behavior of I-CFRP laminates from a thermodynamic perspective. • Propose a matrix representation (Mode) and Hamiltonian (Characteristic parameter) of the I-CFRP laminates' stressing state. • Reveal the phase transition point of I-CFRP laminates: EPB and FS points. [ABSTRACT FROM AUTHOR]

Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by complex clinical symptoms and multi-organ damage. One of the most prevalent complications of SLE is lupus nephritis (LN). Rutin, a natural flavonoid compound found in various plants used in traditional Chinese medicine, has shown promising anti-inflammatory, antioxidant, and renal protective effects. In our study, we treated MRL/lpr mice, a model known for spontaneously developing LN, with Rutin. Our findings reveal that Rutin markedly reduced serum cytokine and autoantibody levels and decreased inflammatory cell infiltration in renal tissues, thereby ameliorating kidney pathology. In vitro experiments indicated that Rutin's therapeutic effect on LN is linked to its significant reduction of oxidative stress in T cells. Further investigations suggest that Rutin enhances oxidative stress management through the modulation of Peroxisome proliferator-activated receptor gamma (PPARγ). We observed that Rutin modulates PPARγ activity, leading to reduced transcriptional activity of NF-κB and STAT3, which in turn inhibits the secretion of inflammatory cytokines such as IL-6, TNF-α, and IL-17. In summary, Rutin can exert an antioxidant effect by regulating PPARγ and shows therapeutic action against LN. [Display omitted] • Rutin ameliorates lupus-like symptoms in MRL/lpr mice by improving hematologic and renal histopathological conditions. • Rutin mitigates T cell oxidative stress through the PPARγ. • PPARγ interacts with STAT3 and NFκB, resulting in reduced STAT3 and NFκB activity. [ABSTRACT FROM AUTHOR]

CDs are applied in the enhancement of EL of Poly (9-vinyl carbazole) with the increased brightness by 54.3 %. [Display omitted] • CDs are applied in the enhancement of EL of PVK with increased brightness by 54.3 %. • The CDs enhanced PVK LEDs possess the EL wavelength of 432 nm. • The CIE coordinates of CDs enhanced PVK LEDs are at (0.17, 0.10) with the brightness of 176 cd m−2. • The mechanisms of charge transport between CDs and PVK are determined by TPV and method of EMD. Carbon dots (CDs) are one species of multifunctionally auxiliary materials with promising application in photoelectrocatalyst and photoelectrodevices. However, there are few reports on enhancing the electroluminescence (EL) of materials by CDs and the effects of CDs on the charge transport dynamics have not been revealed so far. Herein, CDs are firstly successful to be applied in the enhancement of EL of Poly (9-vinyl carbazole), which is set as model material for research, abbreviated as PVK with the EL wavelength of 432 nm. The brightness of CDs enhanced PVK LEDs reaches 176 cd m−2 that obviously 54.3 % higher than that of pure PVK based LEDs and other parameters are all improved. The Commission Internationale d'Eclairage coordinates of CDs enhanced PVK LEDs are situated at (0.17, 0.10). Notably, through the transient photovoltage technology and method of empirical mode decomposition, the mechanisms of charge transport dynamics between CDs and PVK molecules are determined. This work paves a new direction for the improvement of the luminescent properties of electroluminescent devices and a new mentality to understand the effects of CDs on charge transport in the EL process. [ABSTRACT FROM AUTHOR]

Miniaturization is a trend of development toward practical applications for diamond nitrogen-vacancy centers-based sensors. We demonstrate a compact diamond magnetic field sensor device using a standard microfabrication process. A single-crystal-diamond plate is embedded in a cavity formed with stacking of three silicon chips. Thermal compression bonding is implemented at silicon–silicon and diamond–silicon interfaces ensuring mechanical robustness. The specific construction volume for the essential sensor component is about 10 × 10 × 1.5 mm3. By integrating a gradient index lens pigtailed fiber to the sensor device, 532-nm laser light and emitted fluorescence share a common path for excitation and detection. An omega-shaped transmission line for applied microwave power is fabricated directly on the surface of diamond. The integrated sensor device exhibits an optimized sensitivity of 2.03 nT·Hz−1/2 and over twofold enhancement of fluorescence collection efficiency compared to bare diamond. Such a sensor is utilized to measure a magnetic field change caused by switching a household electrical appliance. [ABSTRACT FROM AUTHOR]

Student Dropout Prediction (SDP) is pivotal in mitigating withdrawals in Massive Open Online Courses. Previous studies generally modeled the SDP problem as a binary classification task, providing a single prediction outcome. Accordingly, some attempts introduce survival analysis methods to achieve continuous and consistent predictions over time. However, the volatility and sparsity of data always weaken the models' performance. Prevailing solutions rely heavily on data pre-processing independent of predictive models, which are labor-intensive and may contaminate authentic data. This paper proposes a Survival Analysis based Volatility and Sparsity Modeling Network (SAVSNet) to address these issues in an end-to-end deep learning framework. Specifically, SAVSNet smooths the volatile time series by convolution network while preserving the original data information using Long-Short Term Memory Network (LSTM). Furthermore, we propose a Time-Missing-Aware LSTM unit to mitigate the impact of data sparsity by integrating informative missingness patterns into the model. A survival analysis loss function is adopted for parameter estimation, and the model outputs monotonically decreasing survival probabilities. In the experiments, we compare the proposed method with state-of-the-art methods in two real-world MOOC datasets, and the experiment results show the effectiveness of our proposed model. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the prevalence and characteristics of imipenem-resistant Acinetobacter baumanni isolated from surgical wards in a university hospital, China. A total of 143 non-duplicate A. baumannii were isolated from 517 inpatients in surgery intensive care units (ICUs), burn wards, and general surgery wards. Of these, 102 isolates of A. baumannii (71.3%) were resistant to imipenem. Among imipenem-resistant isolates, all isolates were resistant to almost all antimicrobial agents except polymyxin E, all isolates were positive for blaOXA-23 and bla OXA-51 in addition to IS Aba1, 52 (51%) were positive for blaOXA-58 , 8 (7.8%) contained blaVIM-2 , which co-harbored with blaOXA-58 . Molecular typing revealed the presence of three clones among imipenem-resistant isolates. This study confirmed that A. baumannii strains harboring OXA or VIM type β-lactamases are widely distributed throughout the surgery wards. The data demonstrate that there was a high prevalence of imipenem-resistant A. baumannii infection in the region. [ABSTRACT FROM AUTHOR]

Dynamic characteristics greatly influence the comprehensive performance of a structure. But they are rarely included as objectives in traditional robust optimization of structures. In this study, a robust optimization model including both means and standard deviations of dynamic characteristic indices in the objective and constraint functions is constructed for improving the structural dynamic characteristics and reducing their fluctuations under uncertainty. Adaptive Kriging models are employed for the efficient computation of dynamic characteristics. An intelligent resampling technology is proposed to save computational costs and accelerate convergence of Kriging models, which takes full advantage of the test points for precision verification, the sample points within the local region of the biggest relative maximum absolute error and the near-optimal point to improve the global and local precision of Krigings. The high efficiency of proposed intelligent resampling technology is demonstrated by a numerical example. Finally, an efficient algorithm integrating adaptive Kriging models, Monte Carlo (MC) method, constrained non-dominated sorting genetic algorithm (CNSGA) is proposed to solve the robust optimization model of structural dynamic characteristics. Kriging models are interfaced with MC method to efficiently compute the fitness of individuals during CNSGA. The implementation of proposed methodology is explained in detail and highlighted by the robust optimization of a cone ring fixture with lots of circumferentially distributed holes in a large turbo generator aimed at moving its natural frequencies away from the exciting one. The comparison of the optimized design with the initial one demonstrates that the proposed methodology is feasible and applicable in engineering practice. [ABSTRACT FROM AUTHOR]

Mesoporous hydroxyapatite (HA) was synthesized through gas–liquid chemical precipitation method at ambient temperature without any template. Structure, morphology and pore size distribution of HA were analyzed via X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution electron microscopy and N 2 adsorption/desorption. The chemotherapeutic agent doxorubicin (DOX) was used to investigate the drug adsorption and release behavior of HA. The kinetics of DOX adsorption on HA followed the pseudo-second-order rate expression. Adsorption isotherms at various temperatures were obtained, and the equilibrium data fitted the Langmuir model. The values of thermodynamic parameters (Gibbs free energy, entropy, and enthalpy changes) demonstrated that the adsorption process was spontaneous and endothermic. In vitro pH-responsive (pH = 7.4, 5.8) controlled release was investigated. DOX-loaded HA showed a slow, long-term, and steady release rate. The release rate at pH5.8 was larger than that at pH7.4. Consequently, the as-prepared mesoporous HA has potential applications in controlled drug delivery systems. [ABSTRACT FROM AUTHOR]

In this contribution, we introduced a simple, efficient, and green method of preparing a mesoporous Fe 3 O 4 /hydroxyapatite (HA) composite. The as-prepared material had a large surface area, high pore volume, and good magnetic separability, which made it suitable for targeted drug delivery systems. The chemotherapeutic agent doxorubicin (DOX) was used to investigate the drug release behavior of Fe 3 O 4 /HA composite. The drug release profiles displayed a little burst effect and pH-dependent behavior. The release rate of DOX at pH 5.8 was larger than that at pH 7.4, which could be attributed to DOX protonation in acid medium. In addition, the released DOX concentrations remained at 0.83 and 1.39 μg/ml at pH 7.4 and 5.8, respectively, which indicated slow, steady, and safe release rates. Therefore, the as-prepared Fe 3 O 4 /hydroxyapatite composite could be an efficient platform for targeted anticancer drug delivery. [ABSTRACT FROM AUTHOR]

• A modified-YOLOv5s was proposed to detect defects of wire braided hoses. • K-means++ clustering algorithm is adopted to obtain more suitable anchor boxes. • Focal loss function was adopted to balance between negative and positive samples. • New tailored prediction heads and efficient channel attention (ECA) mechanism were used to improve the detection performance. High-pressure steel wire braided hoses have periodic braided steel wire structure and its productivity is too huge to refrain from making mistakes occasionally such as wire missed wire stacked and wire loosened. The major sticking points in detection are ultra-small, structural similarity and high reflectance of the steel wire braided hoses. Therefore, this paper proposed an automated method based on YOLOv5 to replace traditional naked eyes detection. The anchor boxes were optimized by K-means++ algorithm for defects dataset. Focal loss was used to mitigate the impact of samples imbalance. The predict heads were modified to increase the detection accuracy of ultra-small targets with guaranteeing speed. The effect of efficient channel attention mechanism (ECA) in different positions was analyzed to achieve a better network and increase detection performance. The experimental results showed that the accuracy and recognition efficiency of the proposed modified-YOLOv5s model could reach 92.2% and 23 frames per second. [ABSTRACT FROM AUTHOR]

Whiting 1 is a faint and young globular cluster in the halo of the Milky Way, and was suggested to have originated in the Sagittarius spherical dwarf galaxy (Sgr dSph). In this paper, we use the deep DESI Legacy Imaging Surveys to explore tentative spatial connection between Whiting 1 and the Sgr dSph. We redetermine the fundamental parameters of Whiting 1 and use the best-fitting isochrone (age Ď„ = 6.5 Gyr, metallicity Z = 0.005 and d ⊙ = 26.9 kpc) to construct a theoretical matched filter for the extra-tidal features searching. Without any smooth technique to the matched filter density map, we detect a round-shape feature with possible leading and trailing tails on either side of the cluster. This raw image is not totally new compared to old discoveries, but confirms that no more large-scale features can be detected under a depth of r < =22.5 mag. In our results, the whole feature stretches 0°.1â€"0°.2 along the orbit of Whiting 1, which gives a much larger area than the cluster core. The tails on both sides of the cluster align along the orbital direction of the Sgr dSph as well as the cluster itself, which implies that these debris are probably stripped remnants of Whiting 1 by the Milky Way. [ABSTRACT FROM AUTHOR]

Failure mechanism of complex profile component is always different from that of conventional plate counterpart due to the coupling effect of material and structure. In this work, the low-velocity impact (LVI) and compression after impact (CAI) behaviors of Ω-shape hybrid carbon/Kevlar 3 D orthogonal woven (3DOW) composite made for vehicle B-pillar were comprehensively studied by mechanical tests and mesoscale finite element (FE) analysis at component level, high-speed infrared (IR) thermal imaging, acoustic emission (AE) detection, and microscopic damage morphology characterization. It is found that a through-thickness stress concentration ring leads to high stress state and damage zone penetrating from the impact side to non-impact side along the ring path instead of at the lowest impactor position. The slope effect can not only help the stress conduction downward, but also inhibit the damage propagation from the impact side to the slope. Impact-induced cracks are concentrated around the R corners and extended along the axial direction of the specimen, forming the strip-shaped damage concentration zone along the upper eave of the slope. The Progressive Top-Down Crushing (PTDC) mode of compression after impact is due to the complex deformation process of each yarn such as squeezing, folding and eversion in the crushing process from the top of specimen. And the Middle Indentation Fracture (MIF) mode is the result of bending instability and abrupt fracture. This work presents a reference significance for the further development of composite strengthening components in vehicle bodywork. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses articles in the issue on topics including classroom use of clickers; impact of international trips on students to gain cross-cultural intelligence; and globalization.