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ObjectiveDesignResultsConclusionThere is a noticeable underrepresentation of Black, Indigenous, and People of Color (BIPOC) men in the existing empirical literature examining the sociocultural influences on body image concerns. To fill the gap, this study aimed to gain a better understanding of how sociocultural factors correlated with body dissatisfaction among BIPOC men living within the U.S.Structural equation modeling was used to address this gap by examining how multiple sociocultural factors – interpersonal appearance pressure, media appearance pressure, ethnic-racial identity attitudes (including ethnic-racial salience, stereotype endorsement, and nationalistic assimilation) and ethnic self-hatred towards one’s ethnic group – were linked to dissatisfaction with muscularity, body fat and height in a sample of 181 BIPOC men participants.The proposed cross-sectional path model achieved satisfactory model fit and explained 31.9% in muscularity dissatisfaction, 36.2% in body fat dissatisfaction, and 26.4% in height dissatisfaction. Among direct relationships, interpersonal appearance pressure emerged most prominently associated with height dissatisfaction, whereas media appearance pressure and ethnic self-hatred were more related to muscularity and body fat dissatisfaction. Regarding the mediation effects, media appearance pressure was found to partially mediate the relationship between interpersonal appearance pressure and body dissatisfaction, as well as the relationship between ethnic self-hatred and body dissatisfaction. Furthermore, ethnic self-hatred was found to be predicted by ethnic-racial identity attitudes.This research profoundly expands our understanding of the ethnic and racial complexities surrounding body dissatisfaction among BIPOC men and encourages health practitioners to acknowledge the unique sociocultural and systemic dynamics (ethnic-racial identities and associated stressors) when working with BIPOC men who present with body image concerns. [ABSTRACT FROM AUTHOR]

BackgroundLost radioactive sources needs to be quickly retrieved, positioning of radioactive source in complex environment is the key to find the lost radioactive source. [Propose] This study aims to develope a novel approach for the rapid positioning of orphan sources using a NaI(Tl) array detection device.MethodFirst of all, by leveraging the shadow effect between array detectors, a response curve between gamma-ray incidence angles and counts was obtained through the use of Monte Carlo simulation software. Then, the support vector machine (SVM) method was employed to establish a predictive mathematical model for the counting rate of array detectors as a function of gamma-ray incidence angle, utilizing. Finally, a radioactive source localization physical experiment platform was constructed, and a series of incidence angle response experiments were conducted for the validation of this approach applied to radioactive source localization under varying conditions.ResultsEexperimental results demonstrate that, through the use of the SVM regression prediction model, the maximum average deviation of the angle is 9.21° whilst the minimum is 1.77° for the angle prediction of an orphan 137Cs point source.ConclusionsThis method can achieve rapid and accurate localization of an orphan radioactive source.

Increasing the water–cement ratio and water-reducer dosage of cement slurry enhances its fluidity. However, a high water–cement ratio diminishes the beneficial effects of water reducers on fluidity. The stone content of the slurry decreases as the water-reducer dosage increases. Additionally, the water–cement ratio significantly affects stone content. However, when the water–cement ratio exceeds a threshold value, stone content decreases. Furthermore, the threshold value of the water–cement ratio decreases with increasing water-reducer dosage. Without the addition of the water reducer, as the water–cement ratio increases the overall integrity of the grout stone decreases. The addition of the water reducer alters the surface pore distribution, wherein "uniform small pores" change to "localized large pores." Based on the multi-objective optimization of Matlab, the recommended optimal mix composition for a slow-setting cement slurry is a water–cement ratio of 0.25 and water-reducer dosage of 1.5%. With the use of this optimized mix composition, the stone content and compressive strength increase by 7.8% and 145.6%, respectively, compared to those obtained using the recommended mix ratio in the specifications. Additionally, all relevant performance parameters meet the requirements specified by previous standards. [ABSTRACT FROM AUTHOR]

As one of the most promising alternatives to graphite negative electrodes, silicon oxide (SiOx) has been hindered by its fast capacity fading. Solid electrolyte interphase (SEI) aging on silicon SiOx has been recognized as the most critical yet least understood facet. Herein, leveraging 3D focused ion beam-scanning electron microscopy (FIB-SEM) tomographic imaging, we reveal an exceptionally characteristic SEI microstructure with an incompact inner region and a dense outer region, which overturns the prevailing belief that SEIs are homogeneous structure and reveals the SEI evolution process. Through combining nanoprobe and electron energy loss spectroscopy (EELS), it is also discovered that the electronic conductivity of thick SEI relies on the percolation network within composed of conductive agents (e.g., carbon black particles), which are embedded into the SEI upon its growth. Therefore, the free growth of SEI will gradually attenuate this electron percolation network, thereby causing capacity decay of SiOx. Based on these findings, a proof-of-concept strategy is adopted to mechanically restrict the SEI growth via applying a confining layer on top of the electrode. Through shedding light on the fundamental understanding of SEI aging for SiOx anodes, this work could potentially inspire viable improving strategies in the future. Observing the evolution of the solid electrolyte interphase on SiOx-based electrodes in Li-ion batteries is challenging. Here, authors use three-dimensional tomography to visualize the growth of the interphase on single SiOx particles and propose a mechanical confinement strategy to prevent aging. [ABSTRACT FROM AUTHOR]

With the increasing market demand for high‐performance lithium‐ion batteries with high‐capacity electrode materials, reducing the irreversible capacity loss in the initial cycle and compensating for the active lithium loss during the cycling process are critical challenges. In recent years, various prelithiation strategies have been developed to overcome these issues. Since these approaches are carried out under a wide range of conditions, it is essential to evaluate their suitability for large‐scale commercial applications. In this review, these strategies are categorized based on different battery assembling stages that they are implemented in, including active material synthesis, the slurry mixing process, electrode pretreatment, and battery fabrication. Furthermore, their advantages and disadvantages in commercial production are discussed from the perspective of thermodynamics and kinetics. This review aims to provide guidance for the future development of prelithiation strategies toward commercialization, which will potentially promote the practical application of next‐generation high‐energy‐density lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Estimating the gamma dose rate at one meter above ground level and determining the distribution of radioactive pollution from aerial radiation monitoring data are the core technical issues of unmanned aerial vehicle nuclear radiation monitoring. In this paper, a reconstruction algorithm of the ground radioactivity distribution based on spectral deconvolution was proposed for the problem of regional surface source radioactivity distribution reconstruction and dose rate estimation. The algorithm estimates unknown radioactive nuclide types and their distributions using spectrum deconvolution and introduces energy windows to improve the accuracy of the deconvolution results, achieving accurate reconstruction of multiple continuous distribution radioactive nuclides and their distributions, as well as dose rate estimation of one meter above ground level. The feasibility and effectiveness of the method were verified through cases of single-nuclide (137Cs) and multi-nuclide (137Cs and 60Co) surface sources by modeling and solving them. The results showed that the cosine similarities between the estimated ground radioactivity distribution and dose rate distribution with the true value were 0.9950 and 0.9965, respectively, which could prove that the proposed reconstruction algorithm would effectively distinguish multiple radioactive nuclides and accurately restore their radioactivity distribution. Finally, the influences of statistical fluctuation levels and the number of energy windows on the deconvolution results were analyzed, showing that the lower the statistical fluctuation level and the more energy window divisions, the better the deconvolution results. [ABSTRACT FROM AUTHOR]

Transmission electron microscope (TEM) is thought as one powerful tool to imaging the atomic-level structure of organic inorganic hybrid perovskite (OIHP) materials, which provides valuable and essential guidance toward high performance OIHP-related devices. However, these OIHPs exhibit poor electron beam stability, severely limiting their practical applications in TEM. Here in this article, the application of TEM to obtain atomic-scale image of OIHPs, main obstacles in identifying the degradation product and future prospects of TEM in the characterization of OIHP materials are reviewed and presented. Three potential strategies (sample protection, low temperature technology, and low-dose technologies) are also proposed to overcome the current drawback of TEM technology. [ABSTRACT FROM AUTHOR]

Hyphantria cunea (Drury) (Lepidoptera: Erebidae) is an invasive alien species that is widely distributed in northern China. H. cunea now occurs for the first time in the subtropical areas of China. Despite the importance of identifying oviposition host plants to control the spread of H. cunea, it is not clear whether H. cunea has a new oviposition preference for plant hosts in the new habitat after invading the subtropical region. At the same time, whether the presence of new plant volatiles of new hosts in new habitats influences the oviposition host preference of H. cunea has not been studied. In this study, we investigated the oviposition host plant preferences of H. cunea in the subtropical region of China. In the presence of multiple potential host plants, we found, for the first time, that H. cunea preferred Carya illinoinensis, Morus alba, and Carya cathayensis for oviposition. Through the effects on plant volatiles and on the oviposition, ten volatile compounds with significant differences in relative abundance between five plants with different fitness levels were significantly correlated with the oviposition preference of females. Cis-Hex-3-en-1-ol, (E)-3-Hexen-1-ol, cis-3-Hexenyl acetate 1, and 3-Pentadiene,4-methyl, had a significant positive correlation with the adult oviposition preference. Our results provide an important research basis for the study of green prevention and control strategies of subtropical H. cunea in China. [ABSTRACT FROM AUTHOR]

Wide‐bandgap (WBG) perovskite solar cells (PSCs) are acknowledged as promising candidates for multijunction tandem and building photovoltaics, which attract broad research interest in related research communities. However, the performance of WBG PSCs based on the mixed‐halide perovskites still lags far behind their pure‐iodide counterparts because of the complex compositional evolution, huge photovoltage deficits, and intrinsic spectral losses. Here, by comprehensively understanding the representative WBG PSCs, the main "WBG drawbacks" from the device point of view are discussed in‐depth and three intrinsic critical issues for the growth of high‐quality WBG perovskites are proposed. The prospects for WBG PSCs toward future advancements and commercialization are also presented to guide the coming research hot spots. [ABSTRACT FROM AUTHOR]

This paper investigates single-period inventory management problems with uncertain market demand, where the exact possibility distribution of demand is unavailable. In this condition, it is important to order a reliable quantity which can immunize against distribution uncertainty. To model this type of single-period inventory management problem, this paper characterizes the uncertain demand by generalized interval-valued possibility distributions. We present a novel concept about an uncertain distribution set to describe distribution perturbation characterization. First, we introduce a lambda selection of the interval-valued fuzzy variable, and the uncertain distribution set is a collection of all generalized possibility distributions of lambda selection variables. According to the uncertain distribution set, a new distributionally robust fuzzy optimization method is developed for single-period inventory management problems. Under mild assumptions, the robust counterpart of the proposed fuzzy single-period inventory management model is formulated, which is an optimization program with certain linear objectives and infinitely many integral constraints. We discuss the computational issue of integral constraints and reformulate equivalently the robust counterpart as three deterministic inventory submodels under generalized interval-valued trapezoidal possibility distributions. According to the characteristics of three submodels, a domain decomposition method is designed to find the robust optimal solution that can immunize against uncertainty in our single-period inventory management problem. Finally, some computational results demonstrate the efficiency of the proposed distributionally robust fuzzy optimization method. [ABSTRACT FROM AUTHOR]

Due to its poor stability and rapid metabolism, the biological activity and absorption of epigallocatechin gallate (EGCG) is limited. In this work, EGCG-loaded bovine serum albumin (BSA)/pullulan (PUL) nanoparticles (BPENs) were successfully fabricated via self-assembly. This assembly was driven by hydrogen bonding, which provided the desired EGCG loading efficiency, high stability, and a strong antioxidant capacity. The encapsulation efficiency of the BPENs was above 99.0%. BPENs have high antioxidant activity in vitro, and, in this study, their antioxidant capacity increased with an increase in the EGCG concentration. The in vitro release assays showed that the BPENs were released continuously over 6 h. The Fourier transform infrared spectra (FTIR) analysis indicated the presence of hydrogen bonding, hydrophobic interactions, and electrostatic interactions, which were the driving forces for the formation of the EGCG carrier nanoparticles. Furthermore, the transmission electron microscope (TEM) images demonstrated that the BSA/PUL-based nanoparticles (BPNs) and BPENs both exhibited regular spherical particles. In conclusion, BPENs are good delivery carriers for enhancing the stability and antioxidant activity of EGCG. [ABSTRACT FROM AUTHOR]

Chitosan (CS) and pea protein isolate (PPI) were used as raw materials to prepare nanoparticles. The structures and functional properties of the nanoparticles with three ratios (1:1, 1:2 1:3, CS:PPI) were evaluated. The particle sizes of chitosan–pea protein isolate (CS–PPI) nanoparticles with the ratios of 1:1, 1:2, and 1:3 were 802.95 ± 71.94, 807.10 ± 86.22, and 767.75 ± 110.10 nm, respectively, and there were no significant differences. Through the analysis of turbidity, endogenous fluorescence spectroscopy and Fourier transform infrared spectroscopy, the interaction between CS and PPI was mainly caused by electrostatic mutual attraction and hydrogen bonding. In terms of interface properties, the contact angles of nanoparticles with the ratio of 1:1, 1:2, and 1:3 were 119.2°, 112.3°, and 107.0°, respectively. The emulsifying activity (EAI) of the nanoparticles was related to the proportion of protein. The nanoparticle with the ratio of 1:1 had the highest potential and the best thermal stability. From the observation of their morphology by transmission electron microscopy, it could be seen that the nanoparticles with a ratio of 1:3 were the closest to spherical. This study provides a theoretical basis for the design of CS–PPI nanoparticles and their applications in promoting emulsion stabilization and the delivery of active substances using emulsions. [ABSTRACT FROM AUTHOR]

With the development of urban metro systems, shield tunnels that pass through existing bridge pile foundations have become an inevitable engineering problem. Therefore, ensuring the stability of the strata and existing bridge piles during tunnel construction is a common goal in engineering practice. Currently, research on the mechanical responses of strata and existing piles under different conditions of upper-soft and lower-hard composite strata during shield tunneling has not been conducted extensively. This paper presents a numerical simulation of a shield tunnel passing through an existing bridge pile foundation in upper-soft and lower-hard composite strata. Subsequently, the surface subsidence and mechanical responses of a single pile were analyzed and evaluated. Additional stresses generated in the soil by existing bridge piles and the selection of grouting pressure were considered to optimize the driving pressure of the slurry shield. Allowable values were proposed to evaluate the construction disturbances caused by the tunnel excavation. The results show that the disturbance to the soil and existing piles is significantly influenced by the hard-rock height ratio, and the surface subsidence increases when the hard-rock height ratio decreases. The displacement and internal force of a single pile are significantly influenced by the load applied to the pile. This study demonstrates the changes in the mechanical responses of a single pile during shield tunnel boring, and provides in-depth insights into the deformation control caused by shield underpassing structures in upper-soft and lower-hard composite strata. [ABSTRACT FROM AUTHOR]

Due to the severe volume variations during electrochemical processes, Si‐based anodes suffer from poor cycling performance as the result of a collapsed conductive network. In this regard, a key strategy for fully exploiting the capacity potential of Si‐based anodes is to construct a robust conductive network through rational binder design. In this work, a bio‐inspired conductive binder (PFPQDA) is designed by introducing dopamine‐functionalized fluorene structure units (DA) into a conductivity enhanced polyfluorene‐typed copolymer (PFPQ) to enhance its mechanical properties. Through constructing hierarchical binding networks and resilient electron transportations within both nano‐sized Si and micro‐sized SiOx electrodes via interweaved interactions, the PFPQDA successfully suppresses the electrode expansion and maintains the integrity of conductive pathways. Consequently, owing to the favorable properties of PFPQDA, Si‐based anodes exhibit improved cycling performance and rate capability with an areal capacity over 2.5 mAh cm–2. [ABSTRACT FROM AUTHOR]

This study defined the height ratio of soft-rock strata and established a numerical model for analyzing shield construction in upper-soft, lower-hard composite strata together with field monitoring data. In this way, the influence of shield tunneling while passing under the pile foundation of the culvert at a short distance (the shortest distance is 1.4 m) in the typical upper-soft, lower-hard composite strata in Guangzhou can be examined. Moreover, the reinforcement effects of the ground, the bridges, and the culverts, using the strata-reinforcing plan dominated by the metro jet system (MJS) in a narrow space, are evaluated. Based on the results, (i) the maximum ground subsidence is found at the position in which the height ratio of the soft rock is 1.0. (ii) However, differential subsidence might be found in the subsequent shield construction when the soft-rock height ratio of the adjacent excavated surface ranges from 0 to 0.2 and from 0.5 to 1. (iii) The concentrated release of stress has a greater impact on the structure than the geological conditions of the shield tunneling face. (iv) Reinforcing with the MJS method contains the concentrated release of stress. This study can provide a reference for controlling the deformation of the under-crossing structure in the shield construction of the upper-soft, lower-hard composite strata. [ABSTRACT FROM AUTHOR]

Ground deformation and additional stress on the segments of the firstly constructed tunnel may change significantly due to the construction of another tunnel, which is closely spaced with the existing one. A poor geotechnical condition possibly leads to the interaction between such closely spaced tunnels even making it harder to build such tunnels. A practical project located in Guangzhou City, China, consists of such two parallel tunnels with the smallest distance of 2.6 m, which sat on an upper-soft and lower-hard stratum. A 3D finite element model has been proposed to numerically investigate the behavior of these two parallel tunnels. The numerical results predicted by the FE model are in close agreement with that obtained from the field monitoring system, indicating the accuracy of the proposed FE model. The FE model was then used to further analyze the effect of reinforcing piles in eliminating the detrimental effect on both ground deformation and additional stress of the segments of the existing tunnel as a result of the construction of the new parallel tunnel. The research results obtained from the present paper can provide technical support and guidance for urban subway construction. [ABSTRACT FROM AUTHOR]

"Thin-bed" reservoirs have become important targets of seismic exploration and exploitation. However, traditional amplitude versus offset/amplitude versus angle (AVO/AVA) technologies, for example, those based on Zoeppritz equations and their approximations for a single interface, are not sufficiently accurate for thin-bed stratigraphy. Analytic solutions of thin-bed reflectivity may become practical for thin-bed AVO analysis and inversion. Therefore, a linear analytic approximation of thin-bed P-wave reflectivity is developed under small-incidence and thin-bed assumptions. Numerical simulations show that the amplitude approximation errors are usually smaller than 10% for incidence angles less than 20 degrees, and the thin-bed thicknesses are less than one-tenth of the P-wave wavelength. Based on the least-squares approach, the inversion strategy is proposed using the approximate formula. A synthetic data test shows that the proposed inversion method can produce more accurate thin-bed properties than that based on the Zoeppritz equations, which reveals the potential of the inversion method based on the linear analytic approximate formula in the fine characterization of thin reservoirs. [ABSTRACT FROM AUTHOR]

Abstract: The properties of RbH2PO4/SiO2 composites with different SiO2 pore sizes, prepared by mechanical milling, have been investigated here by various methods. The protonic conductivity is found to depend significantly on SiO2 pore size: the smaller the pore size, the stronger the conductivity enhancement in low-temperature (LT) region, comparing with pure RbH2PO4. The improved conductivity in composites arises from the formation of interface phase layer due to surface interaction between two components. This layer with thickness of ~4nm is structurally disordered or amorphous RbH2PO4 phase, which exhibits the orientation-disorder of H2PO4 − anions induced by the weakening of H-bonds. The interfacial layer exists on the surfaces or inside the pores of SiO2 particles, creating a continuous proton-conductive pathway and leading to the faster proton movement and greater conductivity even at LT. [Copyright &y& Elsevier]

Abstract: The high-temperature (HT) properties of RbH2PO4 have been investigated here by several methods. Two anomalies at T p (∼109°C) and (∼276°C) in differential scanning calorimetry (DSC) measurement are due to structural transition from tetragonal (phase III) to monoclinic (phase II) and monoclinic to an unidentified phase I, respectively. The initial dehydration event in RbH2PO4 occurs at ∼250°C, leading to the formation of dimer crust (Rb2H2P2O7) on the external surface of crystal particles which decelerates the further dehydration process. The conductivity measurement was performed under a highly humidified N2 condition to suppress its dehydration. It revealed two reversible superprotonic phase transition at T p and . For the one at , the conductivity increases sharply by ∼2 orders of magnitude and the high-conductivity phase I was stable till melting. However, the other one at T p shows a relatively small jump in conductivity. [ABSTRACT FROM AUTHOR]

Abstract: The protonic conductivity of (1− x)RbH2PO4–xSiO2 composites prepared by mechanical milling has been investigated in the humid atmosphere. In comparison with pure RbH2PO4, the conductivity enhancement was observed and it was strongly dependent on the amount of SiO2 additives. At low-temperature (LT) phase, the conductivity of composites increased with the addition of SiO2 till x =0.6 at which the maximum conductivity reached. At high-temperature (HT) phase, it was approximately equal to that of pure RbH2PO4 and almost kept unchanged till x =0.5. Therefore, the jump in conductivity at ∼280°C (superprotonic phase transition temperature of RbH2PO4) tended to decrease as x increased and finally disappeared. Furthermore, the conductivity of both LT and HT phases went down at large x values. The conductivity enhancement has been confirmed not to be influenced by absorbed water on the surface of SiO2 particles. In fact, it is due to the formation of structurally disordered or amorphous interface phase. Also, we summarized the different theoretical models of the conductivity enhancement in composites. [Copyright &y& Elsevier]

Abstract: XH2PO4 ionic compounds have emerged as a viable electrolyte for intermediate temperature fuel cells, and here have been subjected to thermal analysis to clarify their high-temperature properties. Thermoanalytical peaks were identified at 231.5, 239 and 349°C for CsH2PO4; 127, 250 and 354°C for RbH2PO4; 232, 270 and 319°C for KH2PO4; 223, 330 and 352°C for NaH2PO4; also, 195 and 220°C for LiH2PO3 (peak temperature values as measured at the same heating rate of 10K/min). The thermal events at 231.5°C in CsH2PO4 and 127°C in RbH2PO4 were previously interpreted as thermal decomposition by numerous researchers, but we confirm their origin in structural phase transition. The high-temperature variations in KH2PO4 and NaH2PO4 are entirely due to thermal dehydration rather than phase transition. We have also examined LiH2PO3, and found, for the first time, an endothermic peak at 195°C, and attributed it to structural phase transition. [Copyright &y& Elsevier]