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Abnormal wear of stitch wires due to interference poses a serious threat to railway safety. To avoid this scenario, the concept of the dynamic envelope of the stitch wire was proposed, accompanied by an interference check method. A multi-node beam model of the stitch wire was established using the finite element method, employed to simulate the pantograph and catenary system, and validated by field test. The dynamic behaviour of the stitch wire was studied, and the concept of dynamic envelope was introduced. Moreover, factors affecting this envelope were analysed, and an interference check method was proposed. Results demonstrate that, the vibration of the stitch wire mainly occurs in the vertical direction and intensifies with increasing speed. Its vertical vibration increases from 70 mm to 137 mm as the train speed goes from 300 km/h to 400 km/h. Cantilever assembly errors and dropper installation issues are the main causes for the abnormal wear of stitch wires. A 100 mm assembly error reduces the clearance from 67 mm to 14 mm, while a 2 m dropper installation error eliminates the clearance entirely. This study provides valuable insights for enhancing the safety of catenary system. [ABSTRACT FROM AUTHOR]

The high temperature compression experiments of 2209 duplex stainless steel were carried out by using Glee-ble3800 thermal simulator, the rate was 0,01~10 s-1, and the deformation temperature was 950~1 100°C. The strain rate and deformation temperature were analyzed and the effect of strain rate and deformation temperature were analyzed. The high-temperature rheological behavior of 2209 duplex stainless steel was investigated, and the effects of strain rate and deformation temperature on the two-phase relationship of 2209 duplex stainless steel were analyzed, the strain rate compensation factor Z was introduced, and the Arrhenius eigenmodel equation was established. The results show that the theoretical value of peak stress calculated numerically by this constitutive model fits well with the experimental results, and the correlation is 97,3 %, which verifies the feasibility of the model. [ABSTRACT FROM AUTHOR]

The autoignition temperature (AIT) serves as a crucial indicator for assessing the potential hazards associated with a chemical substance. In order to gain deeper insights into model performance and facilitate the establishment of effective methodological practices for AIT predictions, this study conducts a benchmark investigation on Quantitative Structure-Property Relationship (QSPR) modelling for AIT. As novelties of this work, three significant advancements are implemented in the AIT modelling process, including explicit consideration of data quality, utilization of state-of-the-art feature engineering workflows, and the innovative application of graph-based deep learning techniques, which are employed for the first time in AIT prediction. Specifically, three traditional QSPR models (multi-linear regression, support vector regression, and artificial neural networks) are evaluated, alongside the assessment of a deep-learning model employing message passing neural network architecture supplemented by graph-data augmentation techniques. [ABSTRACT FROM AUTHOR]

To explore the utility of the 2-[18F]-fluoro-2-deoxy- d- glucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) in the differential diagnosis of IgG4-related lymphadenopathy (IgG4-RLAD) and angioimmunoblastic T-cell lymphoma (AITL). Retrospective analysis of 18F-FDG PET/CT imaging findings in clinically diagnosed IgG4-RLAD and AITL cases was undertaken to record the distribution, morphological characteristics, and imaging features of the affected lymph nodes, as well as FDG uptake of the spleen and bone marrow. Standardised uptake values normalised to lean body mass were evaluated for maximum (SUL max), average (SUL avg), and peak values (SUL peak). Univariate and multivariate logistic regression was used to screen for statistically significant imaging findings to discriminate IgG4-RLAD from AITL. Twenty-two cases of IgG4-RLAD (17 men, five women, median age 49.5 years) and 22 cases of AITL (16 men, six women, median age 55 years) were finally included in the analysis. There were no AITL patients with involvement of a single lymph node region. AITL patients had more involvement of the different nodal regions except cervical and pelvic nodal regions. A practical assessment method based on a combination of SUL peak-LN /SUL avg-liver , SUL peak-spleen , and the number of involved nodal regions, improved the performance for differential diagnosis between both groups with an overall classification accuracy of 90.9%. 18F-FDG PET/CT is a useful tool for distinguishing AITL from IgG4-RLAD, and it can also help determine the optimal biopsy site for suspected cases of IgG4-RLAD or AITL, reduce the need for re-biopsy procedures, and enable physicians to develop timely treatment strategies. • It is essential to exclude AITL before making a clear diagnosis of IgG4-RLAD. • We recommend a practical assessment method based on PET/CT for differential diagnosis. • FDG PET/CT can also aid in determining the optimal biopsy site for suspected cases. [ABSTRACT FROM AUTHOR]

Little is known about the association between common mental disorders (CMD) and labor market integration among refugee and Swedish-born young adults. Socially disadvantaged patients such as refugees are more likely to discontinue their medication use prematurely. This study aimed to identify clusters of individuals with similar psychotropic medication patterns; and examine the relationship between cluster membership with labor market marginalization (LMM) in refugee and Swedish-born young adults with CMD. The study uses a longitudinal matched cohort aged 18-24 years with CMD diagnoses from Swedish registers covering 2006–2016. Dispensed psychotropic medications (antidepressants, antipsychotics, anxiolytics, sedative-hypnotics, mood stabilizers) were collected one year before and after CMD diagnosis. Clusters of patients with similar time courses of prescribed dosages were algorithmically identified. The association of cluster membership with subsequent LMM, (long-term sickness absence, SA, disability pension, DP, or long-term unemployment, UE) was assessed using Cox regression. Among 12,472 young adults with CMD, there were 13.9% with SA, 11.9% with DP, and 13.0% with UE during a mean follow-up of 4.1 years (SD 2.3 years). Six clusters of individuals were identified. A cluster with a sustained increase in all medication types yielded the highest hazard ratio (HR [95% CI]) 1.69 [1.34, 2.13] for SA and 2.63 [2.05, 3.38] for DP. The highest HRs of UE give a cluster with a concentrated peak in antidepressants at CMD diagnosis (HR 1.61[1.18, 2.18]). Refugees and Swedish-born showed similar associations between clusters and LMM. To prevent LMM, targeted support and early assessment of CMD treatment are needed for individuals with a sustained increase in psychotropic medication after CMD diagnosis and for refugees in high-risk clusters for UE characterized by a rapid lowering of treatment dosages, which could be an indicator for premature medication discontinuation. [ABSTRACT FROM AUTHOR]

Mountain Top Removal and Valley Fill (MTR/VF) practices have drastically altered the surface cover, topography and hydrology of many watersheds across the Appalachian region of the US. These practices strip the bedrock from the ridges and peaks of watersheds, before removing the coal seams and depositing the waste fill into adjacent valleys. Existing research has generated conflicting outcomes as to the resulting hydrological impacts in response to storms. This creates potential issues for subsequent mitigation projects seeking to recreate prior hydrological conditions and riparian ecosystems. Our study focused on the potential influence of MTR/VF practices for a series of mined and unmined watersheds across the Eastern Coalfield of Kentucky. We analyzed rainfall-runoff response, focusing on how quickly rainfall was converted to quickflow and how much water left the catchment during storms for the 2022 water year. Lag times were shortened for the mined watersheds while quickflow coefficients reduced when vegetation cover increased. Valley fill-in mined watersheds also appears to create a delayed secondary release of quickflow from headwater locations during more extreme storms. These findings may assist future reclamation/mitigation practices for mined watersheds across Eastern Kentucky aiming to correctly recreate the hydrologic conditions that resemble those of unmined landscapes. [ABSTRACT FROM AUTHOR]

Pipeline junction plays a pivotal role in fluid mixing for biomedical, chemical, and industrial processes. This study introduces an I–L junction for pipeline systems, fostering concurrent flow between branch-pipe injection and the main pipe bulk flow. In contrast to the conventional T-junction with perpendicular injection, the I–L design demonstrates high potential in mitigating vibration-induced fatigue risks, given an optimal branch-to-main pipe diameter ratio, rd. Using unsteady Reynolds-averaged Navier–Stokes equations, the study assesses fluid mixing across a broad range of rd (1 / 12 – 1 / 2.5). The streamline geometry undergoes a transition from well-defined symmetric vortices to unsteady oscillations when the pipe diameters diverge beyond 1/4, arising from vortex shedding in the wake of the branch pipe. Despite the conventional T-junction showing a more homogeneous velocity distribution in the streamwise direction, its turbulent kinetic energy (TKE, both modeled and calculated from the resolved-scale velocities) near the junction is an order of magnitude larger, implying high overall inhomogeneity in the flow. The TKE decays rapidly to an equivalent level compared to the proposed I–L junction approaching discharge, indicating that the peaking of TKE in the T-junction does not significantly contribute to enhanced fluid mixing. Conversely, it can likely result in harmful vibrations inside the pipeline. While the turbulence statistics remain qualitatively unchanged for r d < 1 / 4 , an enlarged discrepancy in pipe diameters beyond r d < 1 / 6 yields more favorable mean surface pressure coefficient, C P ¯ . The results provide insights into pipeline design, recommending an optimal pipe diameter ratio for enhanced mixing of successively collected fluids while retaining improved system reliability. [ABSTRACT FROM AUTHOR]

Canada's migration regime prioritizes the admission of young skilled immigrants while restricting elderly immigrants constructed as non‐contributing dependents. We review and compare the current pathways to family reunification for elderly immigrants. Based on interviews with 16 Chinese skilled immigrant mothers and eight sponsored (grand)parents in Edmonton and Ottawa, we highlight the contributions made by elderly Chinese immigrants to social reproduction, intergenerational cultural preservation, and various forms of transnational support. We also reveal the financial and emotional costs incurred by young skilled immigrants who sought to sponsor their elderly parents for permanent residency. Based on these rich conversations, we propose two policy recommendations to reduce the pressure on sponsoring family members and create opportunities for elderly immigrants to access gainful employment. [ABSTRACT FROM AUTHOR]

The classifications of Fermi-LAT unassociated sources are studied using multiple machine learning (ML) methods. The update data from 4FGL-DR3 are divided into high Galactic latitude (HGL, Galactic latitude | b | > 10°) and low Galactic latitude (LGL, | b | ≤ 10°) regions. In the HGL region, a voting ensemble of four binary ML classifiers achieves a 91 per cent balanced accuracy. In the LGL region, an additional Bayesian–Gaussian (BG) model with three parameters is introduced to eliminate abnormal soft spectrum active galactic nuclei (AGNs) from the training set and ML-identified AGN candidates, a voting ensemble of four ternary ML algorithms reach an 81 per cent balanced accuracy. And then, a catalogue of Fermi-LAT all-sky unassociated sources is constructed. Our classification results show that (i) there are 1037 AGN candidates and 88 pulsar candidates with a balanced accuracy of 0.918 ± 0.029 in HGL region, which are consistent with those given in previous all-sky ML approaches; and (ii) there are 290 AGN-like candidates, 135 pulsar-like candidates, and 742 other-like candidates with a balanced accuracy of 0.815 ± 0.027 in the LGL region, which are different from those in previous all-sky ML approaches. Additionally, different training sets and class weights were tested for their impact on classifier accuracy and predicted results. The findings suggest that while different training approaches can yield similar model accuracy, the predicted numbers across different categories can vary significantly. Thus, reliable evaluation of the predicted results is deemed crucial in the ML approach for Fermi-LAT unassociated sources. [ABSTRACT FROM AUTHOR]

Due to a shortage of river sand for concrete production, manufactured sand (MS) made from crushed rock has gradually become a substitute. It inherently contains some fines content, which has significant effects on the performance of concrete. To study the effects of the MS type and fines content on the workability, cohesiveness, and strength, concrete mixes made with granite MS or limestone MS and different fines contents at various water/binder ratios were tested. Moreover, the packing density, water film thickness (WFT), paste film thickness (PFT), and microstructures of the concrete mixes produced were examined to investigate if their changes were the root causes of the effects of the MS used. It was found that the use of granite MS attained higher workability and strength but lower cohesiveness, which apparently were caused by the higher packing density and larger WFT and PFT. Also, regardless of the MS type, a fines content of about 10% was the optimum for highest packing density and best concurrent workability-cohesiveness-strength performance. Correlation analysis revealed that the MS and fines content exerted their influences on the workability and cohesiveness through the WFT and PFT, and on the strength through the packing density and microstructure. [ABSTRACT FROM AUTHOR]

The MolSSI Driver Interface (MDI) Project is an effort to simplify and standardize the process of enabling tight interoperability between independently developed code bases and is supported by numerous software packages across the domain of chemical physics. It enables a wide variety of use cases, including quantum mechanics/molecular mechanics, advanced sampling, path integral molecular dynamics, machine learning, ab initio molecular dynamics, etc. We describe two major developments within the MDI Project that provide novel solutions to key interoperability challenges. The first of these is the development of the MDI Plugin System, which allows MDI-supporting libraries to be used as highly modular plugins, with MDI enforcing a standardized application programming interface across plugins. Codes can use these plugins without linking against them during their build process, and end-users can select which plugin(s) they wish to use at runtime. The MDI Plugin System features a sophisticated callback system that allows codes to interact with plugins on a highly granular level and represents a significant advancement toward increased modularity among scientific codes. The second major development is MDI Mechanic, an ecosystem management tool that utilizes Docker containerization to simplify the process of developing, validating, maintaining, and deploying MDI-supporting codes. Additionally, MDI Mechanic provides a framework for launching MDI simulations in which each interoperating code is executed within a separate computational environment. This eliminates the need to compile multiple production codes within a single computational environment, reducing opportunities for dependency conflicts and lowering the barrier to entry for users of MDI-enabled codes. [ABSTRACT FROM AUTHOR]

Topographic variables derived from digital elevation models (DEM) are the most commonly used predictor in soil organic carbon (SOC) prediction. The predictability of these variates for the spatial heterogenity of SOC is influenced by the size of DEM resolution. This paper aimed to investigate the resolution effect of the topography at multiple DEM resolutions and select the most important predictors and the optimal resolution for SOC prediction in a large-scale and morphologically complex area. The study area, covering 15 600 km2, was located in a mountainous province in China. A total of 3901 soil samples and three machine learning algorithms including random forest, gradient boosted regression tree, and artificial neural network were used to construct the SOC predictive models at resolutions of 30, 90, 150, 210, 270, 330, and 390 m. Topographic factors were derived from the DEM with an original resolution of 30 m and were subsequently resampled to varying resolutions by using the bilinear interpolation algorithm. The importance of each variate in each predictive model was computed for the most important predictor selection, and the determination coefficient (R2) and Root Mean Square Error (RMSE) of each predictive model were computed for the accuracy evaluation. Comparative analysis on point-based topographic representation, the accuracy of predictive models, and the variable importance was conducted among different resolutions to investigate the resolution effect on the SOC prediction and to select the optimal resolution for this study area. The results showed that topography was the key factor influencing the SOC distribution in this large-scale area due to the region's mountainous nature, and the relative contribution of the topography to predict SOC distribution varied with DEM resolutions. Elevation was the most important topographic factor at all DEM resolutions. Accuracies of predictive models built on the three machine learning algorithms were all dependent on DEM resolution, indicating that DEM resolution had an important effect on SOC prediction. Overall, the random forest predictive models outperformed the other two algorithms, and its most accurate result was obtained at the 210-m resolution with an R2 of 0.25 and an RMSE of 4.77 g kg–1. In conclusion, we found that finer resolutions did not necessarily produce more accurate SOC predictions even in a large-scale and morphologically complex area. Therefore, investigating the resolution effect is suggested to select an optimal resolution for the SOC prediction in other regions characterized by similar geomorphological conditions as this study area. [ABSTRACT FROM AUTHOR]

Stitch wire is the key component in high-speed railway catenary. During the construction and operation of the catenary, tension changes can lead to fracture of the stitch wire. This study proposed a simulation method considering the structure and stress distribution of stitch wire to reveal the effect of tension changes on the fatigue life. Dynamic simulation model at a speed of 300 km/h was constructed to obtain the vibration load. A refined model of stitch wire was used to simulate the contact between the structures. Finally, the fatigue life of stitch wire was calculated when the tension changes by analysing the stress distribution under vibration. Results demonstrate that the lifting effect of the pantograph during operation causes vertical vibrations of stitch wire, and the stress concentration position is located at the connection with its clamp. As the tension increases form 2.0 kN to 5.0 kN, the range of vibration angle at the clamp decreases from 2.73° to 1.33°, and fatigue life increases from 1.36 x 106 to 8.76 x 106. The proposed method provides an accurate approach to simulate the load and fatigue life of stitch wire under real working conditions. [ABSTRACT FROM AUTHOR]

To investigate the value of feature pyramid network (FPN)-based computer-aided detection (CAD) of brain metastases (BMs) before and after non-surgical treatment, and to evaluate its performance in monitoring treatment response of BM on contrast-enhanced (CE) magnetic resonance imaging (MRI). Eighty-five cancer patients newly diagnosed with BM who had undergone initial and follow-up three-dimensional (3D) CE MRI at Liaocheng People's Hospital were included retrospectively in this study. Manual detection (MD) was performed by reviewer 1. Computer-aided detection (CAD) was performed by reviewer 2 using uAI Discover-BMs software. The treatment response was assessed by the two reviewers for each patient separately. A paired chi-square test was used to compare the differences in the detection of BM between MD and CAD. Agreement between MD and CAD in monitoring treatment response was assessed by kappa test. The sensitivities of MD and CAD on initial 3D CE MRI were 78.65% and 99.13%, respectively. The sensitivities of MD and CAD on follow-up 3D CE MRI were 76.32% and 98.24%, respectively. There was a very good agreement between Reviewer 1 and Reviewer 2 in evaluating the treatment response of BM. FPN-based CAD has a higher sensitivity of close to 100% and lower false negatives (FNs) for BM detection, compared to MD. Although CAD had a few shortcomings in reflecting changes of BMs after treatment, it had high performance in monitoring treatment response of BM on CE MRI. • A newly developed deep learning model was used in this study. • This software was first used to evaluate the treatment response of brain metastases. • FPN-based CAD had high performance in monitoring treatment response of BMs. [ABSTRACT FROM AUTHOR]

The constitutive matrices for 32 typical classes of crystalline solids are determined for elastic dielectrics considering couple stress, quadrupole, curvature-based flexoelectric, and other higher-order effects. According to the Neumann's principle, a simple but general method based on the transformation laws of tensor components is presented to derive the constitutive matrices of different classes of crystals. Derivations of constitutive matrices for curvature-based flexoelectricity of crystals of classes Oh (m3m) and C6v (6mm) are explicitly shown as examples. Based on our program, we have: (i) the classical elastic stiffness matrix, piezoelectric matrix, and dielectric matrix obtained in the current work are consistent with those existing results; (ii) the non-classical (higher-order) constitutive matrices in 32 typical classes of crystals, such as couple stress stiffness, coupling between Cauchy stress and couple stress, higher-order dielectrics for quadrupole, curvature-based flexoelectricity, and the converse of flexoelectricity are obtained. The number of independent material constants in constitutive matrices for 32 classes of crystals is also summarized. The present paper provides a reference for solid mechanics researchers facing higher-order multiple physics problems in different categories of crystals and guidance for relevant material experiments. [ABSTRACT FROM AUTHOR]

Due to the poor correlation of index selection and poor evaluation effect in existing methods, a comprehensive evaluation method for urban rail Transportation planning network based on AHP-FUZZY is proposed. Firstly, set the basic principles for constructing an indicator system and construct an evaluation indicator system, Secondly, the network benefit curve and construction cost curve are introduced to screen key indicators, construct a criticality matrix for comprehensive evaluation indicators, and determine the importance of screening indicators through weighted calculation. Finally, the AHP algorithm is used to build a multi-level evaluation structure model, and combined with the FUZZY algorithm to quantitatively evaluate the indicators, a fuzzy membership matrix is constructed to obtain the pros and cons of different indicators, improve the accuracy of the evaluation results, thus realizing the comprehensive evaluation of urban rail Transportation planning network. The results indicate that the proposed method has good performance evaluation. [ABSTRACT FROM AUTHOR]

Sophorolipids (SLs) as a kind of glycolipid biosurfactants are secondary metabolites produced by non-pathogenic yeasts and other microorganisms. Structurally, SLs are composed of a disaccharide sophorose which is β-glycosidically linked to a long fatty acid chain. SLs have broad applications in various areas and many companies are developing SLs products for food, cosmetics, cleaning, personal care, environmental industries, pharmaceutics, and fungicides. Antimicrobial activity, anti-biofilm, and synergistic effect of SLs have been paid more attention since their discovery, especially in recent years. In this review, we reviewed the inhibitory effects of SLs on bacterial and fungal growth and their biofilms formation, and we provided an overview of the synergistic effects of SLs combined with other antimicrobial substances. Furthermore, the antimicrobial mechanisms of SLs action and perspectives on future research for the development of SLs as antimicrobial therapeutics are discussed. [ABSTRACT FROM AUTHOR]

The lattice thermal conductivity of graphene is evaluated using a microscopic model that takes into account the lattice's discrete nature and the phonon dispersion relation within the Brillouin zone. The Boltzmann transport equation is solved iteratively within the framework of three-phonon interactions without taking into account the four-phonon scattering process. The Umklapp and normal collisions are treated rigorously, thereby avoiding relaxation-time and long-wavelength approximations. The mechanisms of the failures of these approximations in predicting the thermal transport properties are discussed. Evaluation of the thermal conductivity is performed at different temperatures and frequencies and in different crystallite sizes. Reasonably good agreement with the experimental data is obtained. The calculation reveals a critical role of out-of-plane acoustic phonons in determining the thermal conductivity. The out-of-plane acoustic phonons contribute greatly and the longitudinal and transverse acoustic phonons make small contributions over a wide range of temperatures and frequencies. The out-of-plane acoustic phonons dominate the thermal conductivity due to their high density of states and restrictions governing the anharmonic phonon scattering. The selection rule severely restricts the phase space for out-of-plane phonon scattering due to reflection symmetry. The optical phonon contribution cannot be neglected at higher temperatures. Both Umklapp and normal processes must be taken into account in order to predict the phonon transport properties accurately. [ABSTRACT FROM AUTHOR]

Nanosuspension of betamethasone dipropionate (BD), an insoluble glucocorticoid drug, was prepared using the medium grinding method, and the process parameters were screened through single factor experiment. Physicochemical characteristics of the prepared BD nanosuspension were studied by scanning electron microscopy, differential scanning calorimetry and powder X-ray scattering techniques. Pharmacodynamic evaluation was conducted on a psoriasis mouse model, and BD nanosuspension showed significant and excellent effects (significantly superior to MTX positive control drugs and physical mixtures in terms of PASI score and histopathological improvement of mouse skin lesions). [ABSTRACT FROM AUTHOR]

Numerical simulations for the wall mass transfer in a turbulent pipe flow were performed at Reynolds numbers (Re) of 40,000, 70,000 and 100,000 and Schmidt number (Sc) of 100, 200, 400 and 1280. Six versions of Low Reynolds Number (LRN) k-ε turbulence models were evaluated by examining the variation of the turbulent viscosity and diffusivity in the wall-normal direction. The predicted values of the turbulent viscosity and diffusivity from the AKN Low Reynolds Number model closely follow the cubic dependence in the near-wall region and found suitable for mass transfer simulations at high Schmidt numbers. The near-wall region was resolved down to y+=0.14 for Reynolds number of 100,000, which allowed the mass transfer to be obtained from the near-wall concentration profile. The exponent of the Schmidt number dependence on the Sherwood number was approximately 0.333 and in agreement with existing mass transfer correlations and experimental data for smooth pipe flow. The predicted mass transfer coefficient was in good agreement with pipe flow results and with experimental and numerical mass transfer results that yielded different Schmidt number dependences over the range considered. [ABSTRACT FROM AUTHOR]

Objective: To clarify the real‐world outcomes in pregnant women with Eisenmenger syndrome (ES) in the new therapeutic era and provide a literature review. Design: Retrospective case and literature review. Setting: Tertiary referral hospital (The Second Xiangya Hospital of Central South University). Sample: Thirteen women with ES delivered between 2011 and 2021. Methods: Respective study and literature reviews. Main outcomes measures: Maternal and neonatal mortality and morbidity. Results: 12/13 (92%) pregnant women were treated with targeted drugs. 9/13 (69%) of patients had heart failure, but no maternal deaths occurred. 12/13 (92%) of women chose caesarean delivery. One pregnant woman gave birth at 37+1 weeks, and the remaining 12 (92%) patients had preterm birth. 10/13 (77%) women gave birth to live infants, of which 9/10 (90%) were low birthweight infants with a mean birthweight of 1575 g. The infant mortality rate was 1/10 (10%). Cardiac functional class improved during pregnancy, probably due to therapy; 11/13 (85%) of the pregnant women were in cardiac functional level III/IV at admission and 12 (92%) were in cardiac functional class II/III at discharge. Our literature review identified 72 cases of pregnancy with ES from 11 studies, which were characterised by a low rate of targeted drug use (28%) and a high maternal mortality rate of 24% in the perinatal period. Conclusion: Our case series and literature review suggest that targeted drugs may be key to improving maternal mortality in ES. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulations are performed to investigate the failure behavior of Al/Al, Al/Fe, and Al/AlFe bi-layers under high strain-rate shock loading. Additional simulations are performed to invesigate solely the tensile response of these systems and to isolate the effects of loading history on damage and failure. Specifically, the compression stage of the shock is excluded from the tensile simulations. This work shows that local structure variation, including the introduction of serrations, plays different roles in controlling damage nucleation depending on the specific loading condition. Under shock loading, the stress for void nucleation and the resulting void distribution is insensitive to an interface structure, whereas under pure tensile loading, the opposite is true, even though the strain rate is comparable. The above difference can be explained based on the corresponding change in the total deformation prior to damage nucleation under shock loading, which is missing from the pure tensile loading. Therefore, it is concluded that whether local interface structure matters under high strain-rate loading depends on the specific loading history and the stress state: the local structure variation matters only when it alters the deformation behavior, and subsequently, damage nucleation and evolution. [ABSTRACT FROM AUTHOR]

RDX/Al/wax explosives (RDX = cyclotrimethylenetrinitramine; (O2NNCH2)3) were studied in experiments designed to elucidate the effects of Al content and the surrounding medium on the energy output of aluminized explosives. Explosives with Al contents of 0%, 15%, and 30% were compared in water and concrete media. Results indicate that the explosive's bubble energy in water is higher (by 66%–90%) than the expansion energy in concrete. Heat, sound, and other energies in water (0.28–0.84 MJ kg–1) were much lower than that in concrete (1.49–2.81 MJ kg–1). For shock wave energy, the different media have much less impact on shock wave energy, with that in water being only 0.7%–7% higher than in concrete. The test data presented in this paper improve our understanding of how Al and the surrounding medium contribute to the energy output of the explosive, which is of great significance for improving the energy utilization efficiency of aluminized explosives in water and concrete. [ABSTRACT FROM AUTHOR]

Abstract Online Only In late July 2022, heavy rains resulted in localised flash flooding across the Upper Kentucky River. To quantify the scale of this event, we analysed hydrometeorological activity using radar, precipitation and stream gauge data for three unregulated watersheds within the headwater forks of the Kentucky River Basin. The July 2022 event resulted from warm‐season elevated thunderstorm activity generating record flooding for the Whitesburg branch of the headwaters. Steeper topography and barren surface cover may have also influenced flooding on a local scale. A better understanding of local flood responses may mitigate future impacts of these events. [ABSTRACT FROM AUTHOR]

Background: The displacements and strains in the cylindrical coordinate system provide information easier to correlate to the pathologic feature of the tubular blood vessel than those in the Cartesian coordinate system. However, distortions and speckle decorrelation have obstructed accurate vascular strain measurement. Objective: This study is to introduce an improved optical coherence elastography (OCE) method based on digital volume correlation (DVC) and correction of distortions to measure the full-field vascular deformation. Methods: Refractive index normalization together with refractive distortion correction based on the Fermat's principle was proposed to recover the actual shape of the vascular wall imaged by optical coherence tomography (OCT). Meanwhile, the displacement fields calculated by DVC were also corrected. The cylindrical coordinate system was created with the origin at the central line of the vascular phantom or sample. Then the full-field 3D displacements in cylindrical coordinates were obtained through coordinate transformation and strains were calculated. Results: A vascular phantom and a porcine artery inflated from 80 mmHg to 85 mmHg were measured. 3D intramural displacements and strains were obtained. The absolute difference between the measured and theoretically calculated strains of the phantom is less than 0.2%. The standard deviation is less than 0.2% as well. A stripe is shown on the radial strain image, which is consistent with the feature of the layered structure. Conclusions: To the best of our knowledge, this is the first experimental study of the 3D intramural vascular deformation under inflation. The proposed DVC-OCE method based on distortion correction and coordinate transformation has the potential to be further developed as an effective full-field nondestructive measurement method of vascular mechanics. [ABSTRACT FROM AUTHOR]

This study considers a manufacturing supply chain comprising a single risk-neutral manufacturer and a single risk-averse retailer. Among them, the manufacturer can produce traditional or green products and has sufficient funds to produce traditional products but lacks green processing costs. When the manufacturer produces green products, it can solve its financial difficulties through bank loans or internal financing from the retailer. This study examines the manufacturing supply chain financing strategy under capital constraints and risk aversion and draws the following conclusions: the manufacturer's wholesale price is the largest and smallest under the bank loan financing and internal financing modes, respectively; the retailer's retail price is the largest and smallest under the bank loan financing and traditional product production modes, respectively. The green input levels between the two financing modes directly depend on the bank loan interest rate and risk aversion. The optimal decisions of the manufacturer and retailer are to sell green products and choose internal financing, while selling traditional products is the worst decision. [ABSTRACT FROM AUTHOR]

The Frobenius-Perron theory of an endofunctor of a \Bbbk-linear category (recently introduced in Chen et al. [Algebra Number Theory 13 (2019), pp. 2005–2055]) provides new invariants for abelian and triangulated categories. Here we study Frobenius-Perron type invariants for derived categories of commutative and noncommutative projective schemes. In particular, we calculate the Frobenius-Perron dimension for domestic and tubular weighted projective lines, define Frobenius-Perron generalizations of Calabi-Yau and Kodaira dimensions, and provide examples. We apply this theory to the derived categories associated to certain Artin-Schelter regular and finite-dimensional algebras. [ABSTRACT FROM AUTHOR]

Understanding the effect of grain boundaries (GBs) on the deformation and spall behavior is critical to designing materials with tailored failure responses under dynamic loading. This understanding is hampered by the lack of in situ imaging capability with the optimum spatial and temporal resolution during dynamic experiments, as well as by the scarcity of a systematic data set that correlates boundary structure to failure, especially in BCC metals. To fill in this gap in the current understanding, molecular dynamics simulations are performed on a set of 74 bi-crystals in Ta with a [110] symmetric tilt axis. Our results show a correlation between GB misorientation angle and spall strength and also highlight the importance of GB structure itself in determining the spall strength. Specifically, we find a direct correlation between the ability of the GB to plasticity deform through slip/twinning and its spall strength. Additionally, a change in the deformation mechanism from dislocation-meditated to twinning-dominated plasticity is observed as a function of misorientation angles, which results in lowered spall strengths for high-angle GBs. [ABSTRACT FROM AUTHOR]

Using the Five-hundred-meter Aperture Spherical radio Telescope (FAST), we have recorded over 1.2 × 104 single pulses from PSR B0823+26 (J0826+2637) at 1.25 GHz with 500 MHz bandwidth. These high-sensitivity observations detected with FAST are unprecedented. We investigated potentially interesting emission features by analyzing the polarimetric individual pulses during the bright state. The average pulse profile has a weak postcursor component and a wide interpulse along with a narrow main pulse. The pulse energy distribution of the main pulse shows the presence of triple emission modes. When the emission ceases in the main pulse component, low-level emission in the interpulse component is detected, whereas the absence of any emission in the postcursor component is shown. In the postcursor emission region, bright pulses are detected in 422 rotations with the relative pulse energy described by a power-law distribution with index of −2.52 ± 0.09, while the peak flux density ratio appears to follow a logarithmic normal distribution. The intervals between bright pulses can be described with a Poisson process with the occurrence rate estimated to be one bright pulse every 14 s. The fluctuation spectral analysis reveals the existence of a form of periodic amplitude modulation unrelated to subpulse drifting in both the main pulse and interpulse components. Furthermore, the modulation patterns in the main pulse and interpulse are found to be locked in pulse longitude, signifying some information transfer between the two magnetic polar regions. [ABSTRACT FROM AUTHOR]

In this study, we report on a detailed single pulse analysis of the radio emission from the pulsar J1401 − 6357 (B1358 − 63) based on data observed with the ultrawideband low-frequency receiver on the Parkes radio telescope. In addition to a weak leading component, the integrated pulse profile features a single-humped structure with a slight asymmetry. The frequency evolution of the pulse profile is studied. Well-defined nulls, with an estimated nulling fraction greater than 2 per cent, are present across the whole frequency band. No emission is detected with significance above 3σ in the average pulse profile integrated over all null pulses. Using fluctuation spectral analysis, we reveal the existence of temporal-dependent subpulse drifting in this pulsar for the first time. A clear double-peaked feature is present at exactly the alias border across the whole frequency band, which suggests that the apparent drift sense changes during the observation. Our observations provide further confirmation that the phenomena of pulse nulling and subpulse drifting are independent of observing frequency, which suggest that they invoke changes on the global magnetospheric scale. [ABSTRACT FROM AUTHOR]

An equation that relates the principal derivative of the Reynolds shear stress and large-scale vorticity fluxes is developed and validated using experimental data in a cylinder near wake. When large-scale vortices prevail, the Reynolds shear stress associated with the coherent motion is a good approximation to the conventional Reynolds shear stress. The latter is essentially determined by the imbalance between the dynamic pressure arising from the streamwise non-homogeneity caused by large-scale vortical structures and the lateral coherent vorticity flux. [ABSTRACT FROM AUTHOR]

A new tool for the exploration and diagnosis of the internal magnetic field of plasmas in the DIII-D tokamak in the form of a constraint on the EFIT (Equilibrium Fitting) Grad–Shafranov code based on the Faraday-effect Radial Interferometer-Polarimeter (RIP) diagnostic is presented, including description, verification, and sample application. The physics underlying the diagnostic and its implementation into EFIT are discussed, and the results showing the verification of the model are given, and the model's limitations are discussed. The influence of the diagnostic's input on the resulting equilibrium parameters is characterized. The effect of electron density profile refinement is evaluated and found to be negligible. A sample application of the diagnostic is shown, indicating that the RIP constraint has similar effects on the equilibrium as motional Stark effect constraints do. [ABSTRACT FROM AUTHOR]

Background: Seizures can occur unpredictably in patients with acute encephalitis syndrome (AES), and many suffer from poor long-term neurological sequelae. Establishing factors associated with acute seizures risk and poor outcomes could support clinical care. We aimed to conduct regional and volumetric analysis of cerebral oedema on magnetic resonance imaging (MRI) in patients with AES. We assessed the relationship of brain oedema with acute seizure activity and long-term neurological outcome.Methods: In a multi-centre cohort study, adults and children presenting with an AES were recruited in the UK. The clinical and brain MRI data were retrospectively reviewed. The outcomes variables were inpatient acute seizure activity and neurological disability at six-months post-discharge. A poor outcome was defined as a Glasgow outcome score (GOS) of 1-3. We quantified regional brain oedema on MRI through stereological examination of T2-weighted images using established methodology by independent and blinded assessors. Clinical and neuroimaging variables were analysed by multivariate logistic regression to assess for correlation with acute seizure activity and outcome.Results: The study cohort comprised 69 patients (mean age 31.8 years; 53.6% female), of whom 41 (59.4%) had acute seizures as inpatients. A higher Glasgow coma scale (GCS) score on admission was a negative predictor of seizures (OR 0.61 [0.46-0.83], p = 0.001). Even correcting for GCS on admission, the presence of cortical oedema was a significant risk factor for acute seizure activity (OR 5.48 [1.62-18.51], p = 0.006) and greater volume of cerebral oedema in these cortical structures increased the risk of acute seizures (OR 1.90 [1.12-3.21], p = 0.017). At six-month post-discharge, 21 (30.4%) had a poor neurological outcome. Herpes simplex virus encephalitis was associated with higher risk of poor outcomes in univariate analysis (OR 3.92 [1.08-14.20], p = 0.038). When controlling for aetiology, increased volume of cerebral oedema was an independent risk factor for adverse neurological outcome at 6 months (OR 1.73 [1.06-2.83], p = 0.027).Conclusions: Both the presence and degree of cerebral oedema on MRIs of patients with AES may help identify patients at risk of acute seizure activity and subsequent long-term morbidity. [ABSTRACT FROM AUTHOR]

Background: Although many studies have indicated that Psoriasis (PsO) could contribute to the risk of lung cancer, no study has reported a clear causal association between them. Our aim was to explore the potential causal association between PsO and the lung cancer risk using Mendelian randomization (MR) design. Methods: To explore a causal association between the PsO and lung cancer, we used large‐scale genetic summary data from genome‐wide association study (GWAS), including PsO (n = 337 159) and lung cancer (n = 361 586), based on previous observational studies. Our main analyses were conducted by inverse‐variance weighted (IVW) method with random‐effects model, with a complementary with the other two analyses: weighted median method and MR‐Egger approach. Results: The results of IVW methods demonstrated that genetically predicted PsO was significantly associated with higher odds of lung cancer, with an odds ratio (OR) of 1.06 (95%CI, 1.01–1.12; P = 0.02). Weighted median method and MR‐Egger regression also demonstrated directionally similar results (All P < 0.05). In addition, both funnel plots and MR‐Egger intercepts indicated no directional pleiotropic effects between PsO and lung cancer. Conclusions: Our study provided potential evidence between genetically predicted PsO and lung cancer, which suggested that enhanced screening for lung cancer allows early detection of lung cancer. [ABSTRACT FROM AUTHOR]

The acoustic pressure of an unbounded acoustic field with multiple prolate spheroids with the Robin boundary conditions subjected to a time-harmonic point source located at an arbitrary location is solved semi-analytically in this work. This resultant solution is the so-called dynamic Green's function, which is important for acoustic problems such as sound scattering and noise control. It can be obtained by combining the fundamental solution with a homogenous solution, which is determined by using the collocation multipole procedure to satisfy the required Robin boundary conditions. To consider the geometries as described herein, the regular solution is expanded with angular and radial prolate spheroidal wave functions. As an alternate to the complex addition theorem applied to problems in multiply connected domains, by the directional derivative, the multipole expansion is computed in a straightforward manner among different local prolate spheroidal coordinate systems. By taking the finite terms of the multipole expansion at all collocating points, an algebraic system is acquired, and then the unknown coefficients are determined to complete the proposed dynamic Green's function by the Robin boundary conditions. The present results of one spheroid agree with the available analytical solutions. For the case of more than one spheroid, the proposed results are verified by comparison with the numerical method such as the boundary element method (BEM). It indicates that the present solution is more accurate than that of the BEM and shows a fast convergence. In the end, the parameter study is performed to explore the influences of the exciting frequency of the point source, the surface admittance, the number and the separation of spheroids, and the aspect ratio of spheroid on the dynamic Green's functions. The proposed results can be applied to solve the time-harmonic problems for an unbounded acoustic field containing multiple spheroids. In the form of numerical Green's functions, they can improve the computational efficiency and increase the application of the boundary integral equation method. [ABSTRACT FROM AUTHOR]

In this paper, the residual stress evolution and surface morphology of quenched 20Cr2Ni4A steel after surface grinding with alumina grinding wheel was investigated. The initial compressive residual stress in the surface layer evolved into tensile stress after grinding. Since thermal stress was the dominated factor, the effect of grinding speed and grinding depth showed significant effects on the level of residual stress. The tensile stress on the ground surface increased by more than 50 % when grinding speed increased from 26 m/s to 34 m/s at the feed speed of 0.19 m/s to 0.26 m/s. The increase of grinding depth from 0.02 mm to 0.03 mm resulted in the increase rate of tensile stress varying between 54 % and 85 % at specific feed speed and grinding speed. Due to the extrusion and cutting of abrasive particles, plastic deformation and grooves were found on the machined surface. The influence of grinding heat and grinding force caused a plastic deformation layer and grinding burn layer within 20 μm. [ABSTRACT FROM AUTHOR]

The behavior of displacement field due to a screw dislocation is similar to the angular basis function (ABF) Arg(z). It is different from the radial basis function (RBF) ln(r) that is used to describe the velocity potential of a sink or source. Nevertheless, the complex-valued fundamental solution ln(z) contains the two parts of RBF ln(r) and ABF Arg(z). In this paper, not only the RBF in the null-field boundary integral equation (BIE) but also the ABF for the screw dislocation are employed to study the interaction between a screw dislocation and an elastic elliptical inhomogeneity. This problem is decomposed into a free field with a screw dislocation and a boundary value problem containing an elliptical inhomogeneity. The boundary value problem is solved by using the RBF and the null-field BIE. Since the geometric shape is an ellipse, the degenerate kernel is expanded to a series form under the elliptical coordinates, while the unknown boundary densities are expanded to eigenfunctions. By combining the degenerate kernel and the null-field BIE, the boundary value problem can be easily solved. The inconsistency between Sendeckyj (In: Simmons JA, et al (eds) Fundamental aspects of dislocation theory. US National Bureau of Standards, Gaithersburg, pp 57–69, 1970) and Gong and Meguid (Int J Eng Sci 32(8):1221–1228, 1994) for the problem was also found by using the present approach. The error in Gong and Meguid (Int J Eng Sci 32(8):1221–1228, 1994) was also printed out. Finally, some examples are demonstrated to verify the validity of the present approach. [ABSTRACT FROM AUTHOR]

Background. The surgical management of children with bronchiectasis has seldom been reported. Objective. To describe the presentation, surgical management and outcomes in children with bronchiectasis presenting for surgery. Methods. We retrospectively reviewed the electronic records of 0 - 13-year-old children who underwent pulmonary resection for bronchiectasis at Inkosi Albert Luthuli Central Hospital, Durban, South Africa, between January 2004 and December 2014. Clinical, radiological and preoperative bronchoscopic findings, as well as surgical and histological outcomes, were analysed. Results. Eighty-eight patients underwent surgical resection. The female/male ratio was 3:2, with a mean age at surgery of 8.2 (range 2 - 13) years; 39 patients were HIV infected and 39 were HIV uninfected. Tuberculosis (TB) (n=68; 77.2%) was the most common cause of bronchiectasis, and recurrent chest infection (n= 45; 51.1%) was the most common clinical finding. Radiological examination confirmed isolated left-sided disease in 40 children (45.4%), isolated right-sided disease in 28 (31.8%) and bilateral disease in 20 (22.7%). Saccular disease with fibrocavitation (n=35; 39.7%) was the most common morphological disease type. Preoperative bronchoalveolar lavage samples confirmed a bacterial cause in 27 patients (30.6%). The most common operative procedures were primary pneumonectomy in 33 patients (37.0%), lobectomy in 30 (34.0%) and bilobectomy in 13 (14.7%). Seventy-five patients were asymptomatic after the operation and complications occurred in 13. Two children (2.2%), one with sepsis and the other with intraoperative hypoxia, died. Seventy patients underwent complete resection. At 1 month after surgery, 89.2% of patients were asymptomatic, while 77.7% of symptomatic patients were HIV positive. Conclusions. Complete pulmonary resection in children with advanced-stage bronchiectasis is safe, with a low morbidity and mortality. Surgery in HIV-positive patients was not associated with worse outcomes and is not contraindicated. HIV- and TB-preventive measures could reduce the burden of childhood bronchiectasis. [ABSTRACT FROM AUTHOR]

Changes in levels of the inhibitory neurotransmitter γ‐aminobutyric acid (GABA) may underlie aging‐related changes in brain function. GABA and co‐edited macromolecules (GABA+) can be measured with MEGA‐PRESS magnetic resonance spectroscopy (MRS). The current study investigated how changes in the aging brain impact the interpretation of GABA+ measures in bilateral auditory cortices of healthy young and older adults. Structural changes during aging appeared as decreasing proportion of grey matter in the MRS volume of interest and corresponding increase in cerebrospinal fluid. GABA+ referenced to H2O without tissue correction declined in aging. This decline persisted after correcting for tissue differences in MR‐visible H2O and relaxation times but vanished after considering the different abundance of GABA+ in grey and white matter. However, GABA+ referenced to creatine and N‐acetyl aspartate (NAA), which showed no dependence on tissue composition, decreased in aging. All GABA+ measures showed hemispheric asymmetry in young but not older adults. The study also considered aging‐related effects on tissue segmentation and the impact of co‐edited macromolecules. Tissue segmentation differed significantly between commonly used algorithms, but aging‐related effects on tissue‐corrected GABA+ were consistent across methods. Auditory cortex macromolecule concentration did not change with age, indicating that a decline in GABA caused the decrease in the compound GABA+ measure. Most likely, the macromolecule contribution to GABA+ leads to underestimating an aging‐related decrease in GABA. Overall, considering multiple GABA+ measures using different reference signals strengthened the support for an aging‐related decline in auditory cortex GABA levels. [ABSTRACT FROM AUTHOR]

Toroidal current profile measurements in the tokamak plasma edge are critical for fusion plasma physics research and model validation. A three-wave Faraday-effect polarimeter-interferometer with a sub-centimeter spatial resolution is proposed on the DIII-D tokamak to determine the edge current profile via Abel inversion. By using probe beams with 316 µm wavelength, a low-field-side, vertical-view, single-pass optical layout covering the plasma edge region (R = 2.15–2.27 m) is assessed. Measurements with no greater than 0.1° polarimetric systematic uncertainty, no greater than 0.01° polarimetric root-mean-square noise (1 kHz bandwidth), and a 0.8 cm radial chord spacing are considered feasible based on the achieved performance of existing systems using similar wavelengths on fusion devices. Synthetic diagnostic calculations taking various factors into account, such as diagnostic uncertainty and quality of magnetic flux surfaces, find that the edge current profile can be determined with up to 0.12 MA/m2 uncertainty, or about 10% of the peak current density in the pedestal of an investigated high-confinement plasma. [ABSTRACT FROM AUTHOR]

Conventional functional MRI (fMRI) with blood-oxygenation level dependent (BOLD) contrast is an important tool for mapping human brain activity non-invasively. Recent interest in quantitative fMRI has renewed the importance of oxidative neuroenergetics as reflected by cerebral metabolic rate of oxygen consumption (CMRO2) to support brain function. Dynamic CMRO2 mapping by calibrated fMRI require multi-modal measurements of BOLD signal along with cerebral blood flow (CBF) and/or volume (CBV). In human subjects this "calibration" is typically performed using a gas mixture containing small amounts of carbon dioxide and/or oxygen-enriched medical air, which are thought to produce changes in CBF (and CBV) and BOLD signal with minimal or no CMRO2 changes. However non-human studies have demonstrated that the "calibration" can also be achieved without gases, revealing good agreement between CMRO2 changes and underlying neuronal activity (e.g., multi-unit activity and local field potential). Given the simpler set-up of gas-free calibrated fMRI, there is evidence of recent clinical applications for this less intrusive direction. This up-to-date review emphasizes technological advances for such translational gas-free calibrated fMRI experiments, also covering historical progression of the calibrated fMRI field that is impacting neurological and neurodegenerative investigations of the human brain. [ABSTRACT FROM AUTHOR]

To examine the associations between food insecurity and health, access to care, affordability of care, financial burden of care, and financial hardships among US adults during the COVID-19 pandemic and examine whether the associations were less pronounced among adults with safety nets. We conducted a retrospective longitudinal cohort study using the 2020–2021 Medical Expenditure Panel Survey. Linear probability models were used to assess the associations between food insecurity in one year and the outcomes of interest in the following year while adjusting for baseline characteristics. We performed the analyses for the entire population and then conducted stratified analyses for adults with and without Supplemental Nutrition Assistance Program (SNAP) benefits or Medicaid coverage. Compared with food-secure adults, food-insecure adults were 9.1 percentage points less likely to report life satisfaction and 9.9, 10.2, and 13.2 percentage points more likely to experience delays in getting medical care, postpone or forgo medical care because of cost, and struggle with paying medical bills. Food-insecure adults were 30.4, 27.2, and 23.5 percentage points more likely to face challenges in affording necessities, paying utility bills, and meeting rent or mortgage payments on time than food-secure adults. Notably, the strengths of these associations were attenuated among adults with SNAP benefits or Medicaid coverage. Food insecurity was associated with poor health, limited access to and affordability of care, and a greater financial burden of care among US adults during the pandemic. Nevertheless, safety net programs can play a critical role in alleviating adverse consequences. [ABSTRACT FROM AUTHOR]

In order to accurately describe the high temperature deformation behavior of GGG70L ductile iron, the thermal simulation experiments with deformation rate of 0,01~10 s- 1 were carried out at 800~1 100 °C by Gleeble-1500D thermal simulation machine. The deformation behavior of GGG70L ductile iron was studied. The temperature compensated strain rate Zener-Hollomon parameter was introduced, and the constitutive model of GGG70L ductile iron was established based on the strain compensated Arrhenius model. The results show that the theoretical value of peak stress calculated by the constitutive model is in good agreement with the experimental results, and the correlation is 97,8 %, which can accurately describe the high temperature deformation behavior of GGG70L ductile iron [ABSTRACT FROM AUTHOR]