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Motivated by the multiferroic effects and quantum magnetization plateaus in the skew chain antiferromagnets T 2 V 2 O 7 (T = Ni, Co), we have conducted a detailed density function theoretical study on Co 2 V 2 O 7. The results show that the nearest-neighbor interchain interaction (J 3 / k B = − 35.57 K) is not much greater than the intrachain interactions (J 1 / k B = − 19.54 K and J 2 / k B = 27.55 K), showing the absence of interchain dimerization of the Co ions. This indicates that the "dimer+monomer" model used for Ni 2 V 2 O 7 [Cao et al., Phys. Rev. B 106, 184409 (2022)] is no longer applicable to Co 2 V 2 O 7. Finally, the exact diagonalization of spin Hamiltonian, including anisotropic exchanges, produces the experimentally observed 1/2 and 3/4 magnetization plateaus. [ABSTRACT FROM AUTHOR]

Recently, photothermoelectric effect of thermoelectric materials has been hotly explored to develop self-powered and large bandwidth photodetectors working at ambient conditions. However, the key parameters for optimized photothermoelectric effect are still elusive. Here, based on the two-temperature model under static condition, we theoretically studied the key parameters to optimize the photothermoelectric performance of thermoelectric materials. Results verify that when the incident electromagnetic wave only generates electronic intra-band excitation, there is an ideal carrier concentration to optimize the photothermoelectric voltage; when the wavelength of a detected electromagnetic wave can resonantly excite quasi-particle (like phonons) except electrons, the photothermoelectric voltage can be enhanced significantly around the resonant wavelength regime; and when the electronic inter-band transition can be excited by an electromagnetic wave, photothermoelectric voltage is significantly increased due to the high optical absorption. As an example, the theoretical dependence of the photothermoelectric voltage of SnSe on wavelength is in line with the experimental result. This work elucidates the crucial parameters of thermoelectric materials to achieve the ideal photothermoelectric performance. [ABSTRACT FROM AUTHOR]

We propose and investigate a novel coherent laser array design based on laterally coupled photonic crystal surface-emitting lasers (PCSELs). As a new type of semiconductor laser technology, PCSELs have field confinement in a planar cavity and laser beam emission in the surface normal direction. By engineering lateral couplings between PCSELs with heterostructure photonic crystal designs, we can achieve coherent operations from an array of PCSELs. In this paper, we demonstrate coherent operation from a passively coupled PCSEL array design. We fabricated PCSEL array devices on a GaAs-based quantum well heterostructure at a target wavelength of 1040 nm. Experimental results show that the 2-by-2 PCSEL arrays have spectral linewidth of 0.14–0.22 nm. Beam combining performance was characterized by self-interference experiments. Similar coherency between the PCSEL array and single PCSEL device was observed. Our compact PCSEL array designs by passive lateral coupling have potential applications in fields of on-chip photonic computing, quantum, and information processing. [ABSTRACT FROM AUTHOR]

The surface optical (SO) phonon replica in photoluminescence (PL) spectroscopy of nitride nanowires (NWs) was theoretically investigated in this study. The dispersive relationships of SO phonon mode in anisotropic wurtzite (WZ) and isotropic zinc-blende (ZB) crystal structure NWs with circular and square cross sections (CSs) were derived within the framework of the dielectric continuum model. Based on the energy and momentum conservation laws, a constraint relationship between the frequency and wave-number was constructed for SO phonon-assisted excitonic PL spectra in the NW structure. By combining the dispersive and constraint relationships, the frequency and wave-number of the SO phonon replica in the PL spectra could be determined. The WZ and ZB crystal structures of nitride semiconductor were considered. The influences of surface factors including the CS shape, dielectric medium, and environment temperature on the frequency and photon wavelength of the band-edge emission of the SO phonon replica were studied in detail. Numerical results reveal that the crystal structure, surface factors, and environment temperature greatly affect the frequency and photon wavelength of the band-edge emission of the SO phonon replica. The calculated results for the photon wavelength agree well with the experimental values of the SO phonon replica in AlN NWs. The results of the dielectric effect obtained here are also supported by previous experimental and theoretical results for nitrides and other semiconductor NWs. The present theoretical scheme and numerical results can be used to analyze and design the SO phonon replica in PL spectra of nanostructures. [ABSTRACT FROM AUTHOR]

Rescattering of stimulated Raman side scattering (SRSS) is observed for the first time via two-dimensional (2D) particle-in-cell (PIC) simulations. We construct a theoretical model for the rescattering process, which can predict the region of occurrence of mth-order SRSS and estimate its threshold. The rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion scheme. Hot electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS, but there is no cascade acceleration to produce superhot electrons. Parametric studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion. [ABSTRACT FROM AUTHOR]

The reservoir of sulphur accounting for sulphur depletion in the gas of dense clouds and circumstellar regions is still unclear. One possibility is the formation of sulphur chains, which would be difficult to detect by spectroscopic techniques. This work explores the formation of sulphur chains experimentally, both in pure H |$_2$| S ice samples and in H |$_2$| O:H |$_2$| S ice mixtures. An ultrahigh vacuum chamber, ISAC, eqquipped with FTIR and QMS, was used for the experiments. Our results show that the formation of H |$_2$| S |$_x$| species is efficient, not only in pure H |$_2$| S ice samples, but also in water-rich ice samples. Large sulphur chains are formed more efficiently at low temperatures (⁠|$\approx$| 10 K), while high temperatures (⁠|$\approx$| 50 K) favour the formation of short sulphur chains. Mass spectra of H |$_2$| S |$_x$|⁠ , x = 2–6, species are presented for the first time. Their analysis suggests that H |$_2$| S |$_x$| species are favoured in comparison with S |$_x$| chains. Nevertheless, the detection of several S |$_x^+$| fragments at high temperatures in H |$_2$| S:H |$_2$| O ice mixtures suggests the presence of S |$_8$| in the irradiated ice samples, which could sublimate from 260 K. ROSINA instrument data from the cometary Rosetta mission detected mass-to-charge ratios 96 and 128. Comparing these detections with our experiments, we propose two alternatives: (1) H |$_2$| S |$_4$| and H |$_2$| S |$_5$| to be responsible of those S |$_3^+$| and S |$_4^+$| cations, respectively, or (2) S |$_8$| species, sublimating and being fragmented in the mass spectrometer. If S |$_8$| is the parent molecule, then S |$_5^+$| and S |$_6^+$| cations could be also detected in future missions by broadening the mass spectrometer range. [ABSTRACT FROM AUTHOR]

Background: The surface brittle fracture of cermet coating seriously restricts its application. Accurate evaluation of the fracture toughness of cermet coating is a prerequisite for improving its life. Objective: This paper aims to propose an accurate characterization method for fracture toughness of cermet coating. Methods: By coupling instrumented indentation and X‑ray computed tomography (XCT), the indentation-induced fracture behaviors under various loads within WC-12%Co coatings were studied. The three-dimensional subsurface crack morphologies and the damage evolution within the coating were nondestructively observed by XCT. The indentation response was correlated with the damage evolution. The impact of substrate effects on indentation-induced fracture behaviors was further studied using finite element analysis (FEA). Results: The Palmqvist shape of the indentation crack under low loads was successfully identified. The first pop-in event in the load-displacement (P-h) curve was determined to be triggered by bottom cracking, marking the onset of the multiple fracture mode. Laugier's equation offered a stable and reliable estimation of fracture toughness for the coating in the radial cracking mode. Conclusions: XCT plays a crucial role in selecting the appropriate equation for indentation toughness calculation. The critical indentation depth for the first pop-in was suggested as the threshold for reliably extracting intrinsic fracture toughness of cermet coatings. Numerical results revealed a constant linear relationship between the critical depth and coating thickness, and a high sensitivity of the critical depth to yield stress of the substrate. The proposed analytical procedure holds potential for generalization to diverse cermet coatings on metal substrates. [ABSTRACT FROM AUTHOR]

To prepare a high quality Fe-based ceramic composite coating, 17-4ph+30% WC alloy powder was clad onto a 17-4ph stainless steel substrate by high speed laser cladding (HSLC) and a metal matrix composite (MMC) clad without cracks and pores was achieved. The WC particle distribution, microstructure formation and evolution mechanism of the MMC laser clad were studied in detail. The results show that the phase composition of the MMC laser clad mainly includes γ-Fe, W2C, WC, Ni3Fe, Cr23C6, etc. The WC particles in the MMC laser clad show a good metallurgical bonding with the 17-4ph substrate, the dilution rate of the clad is low and the higher heat input causes more WC particles to melt and decompose, generating more hard strengthening phases. The grain refinement strengthening, solid solution strengthening and second phase strengthening are more prominent, which provides a scientific basis for optimizing the preparation of high quality Fe-based ceramic composite coatings. [ABSTRACT FROM AUTHOR]

In 1980, Bressoud conjectured a combinatorial identity A j = B j for j = 0 or 1. In this paper, we introduce a new partition function B ~ 0 which can be viewed as an overpartition analogue of the partition function B 0 . An overpartition is a partition such that the last occurrence of a part can be overlined. We build a bijection to get a relationship between B ~ 0 and B 1 , based on which an overpartition analogue of Bressoud's conjecture for j = 0 is obtained. [ABSTRACT FROM AUTHOR]

We present a practical scheme for the efficient preparation of laser–cooled 43 Ca + ions in an ion trap. Our approach integrates two well-established methods: isotope-selective photoionization and isotope-specific parametric excitation. Drawing inspiration from the individual merits of each method, we have successfully integrated these techniques to prepare extended chains of 43 Ca + ions, overcoming the challenge posed by their low natural abundance of 0.135% in a natural source. Furthermore, we explore the subtleties of our scheme, focusing on the influence of different factors on the purification process. Our investigation contributes to a broader understanding of the technique and highlights the adaptability of established methods in addressing specific isotopic challenges. [ABSTRACT FROM AUTHOR]

We explored the coupling between magnetic and magneto-transport properties in MnBi2Te4 crystals with Fermi energy EF ranging from 10 to 100 meV in the conduction band. Electrical, magnetic, and magneto-transport measurements reveal distinct behaviors depending on EF. At lower EF values (10 meV), MnBi2Te4 exhibits degenerate-semiconductor-like electrical transport and ferrimagnetism, with weak coupling between magneto-resistance and ferrimagnetism. In contrast, MnBi2Te4 displays metallic transport and antiferromagnetism (AFM) at higher Fermi energies, with magneto-resistance strongly coupled to antiferromagnetism and canted antiferromagnetism under a large external magnetic field. Remarkably, Hall measurements demonstrate a pronounced anomalous Hall resistivity (AHR) when the EF of MnBi2Te4 is 10 meV, larger than that reported for other bulk MnBi2Te4 crystals in the literature. Significant AHR is attributed to the Berry-phase effect in electronic-band structure based on first-principles calculation. The evolution of magnetic and magneto-transport properties in EF shifted MnBi2Te4 can be semi-quantitatively explained by the Ruderman–Kittel–Kasuya–Yosida interaction between neighboring MnTe layers. Our work suggests that the strongly Fermi-energy-sensitive magneto-transport properties observed in MnBi2Te4 may be useful in developing magnetic sensors/detectors. [ABSTRACT FROM AUTHOR]

In this study, polyaniline-derived carbon doped with nitrogen was synthesized through in-situ polymerization and high-temperature carbonization, using aniline as the raw material and ammonium persulfate as the initiator. The phase, morphology, and composition of polyaniline-derived carbon at different carbonization temperatures were characterized by thermogravimetric, transmission electron microscopy, fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman, and Brunauer–Emmertt–Teller. The electromagnetic parameters of polyaniline-derived carbon with a filler content of 20 wt % were measured by a vector network analyzer, and the electromagnetic wave absorption performance was calculated using the transmission line method. The results showed that the samples had a porous morphology, and the specific surface area of polyaniline-derived carbon-650 and polyaniline-derived carbon-700 was up to 12 times greater than that of polyaniline. Furthermore, polyaniline-derived carbon-700 exhibited excellent electromagnetic wave absorption performance, with the best reflection loss at a thickness of 2.5 mm being –44.35 dB. The effective absorption bandwidth was 3.23 GHz (8.56–11.79 GHz). The effective absorption of C, X, and Ku band electromagnetic waves could be achieved by adjusting the coating thickness. The hybridization of N atoms and C atoms in polyaniline-derived carbon induced magnetism, and the synergistic effect with enhanced dielectric loss improved the electromagnetic loss capacity of the material, optimized impedance matching, and enhanced the electromagnetic wave absorption performance of polyaniline-derived carbon. The electromagnetic wave dissipation mechanism of polyaniline-derived carbon material mainly included dipole polarization, interface polarization, conductivity loss, and magnetic loss caused by N doping. The synthesized polyaniline-derived carbon is a potential electromagnetic wave absorbing material. [ABSTRACT FROM AUTHOR]

Lead–tin-based perovskite films have great potential for application in efficient solar cells, including tandem, and underwater solar cells. Continuous pin-hole-free MAPbxSn1−x(I0.75Br0.25)3 (with x value of 0, 0.25, 0.5, 0.75, and 1) were spin-casted on glass substrates without the use of antisolvent from a precursor ink containing methylammonium acetate (MAAc) additive. The bandgap decreases with the increase of tin/lead ratio and is tunable from ~ 1.28 to ~ 1.71 eV. MAPbxSn1−x(I0.75Br0.25)3 films deposited by a one-step spin-casting process using MAAc in the ink have similar properties to films deposited by a two-step spin casting process using MAAc-free ink and an antisolvent step. [ABSTRACT FROM AUTHOR]

Purpose: To determine the relationship between abdominal hernia and obesity. Although obesity is frequently cited as a risk factor for abdominal hernia, few studies have confirmed this association (Menzo et al. Surg Obes Relat Dis 14:1221–1232. 10.1016/j.soard.2018.07.005, 2018). Methods: A cross-sectional study of primary care ambulatory patients aged older than 16 years treated at UCLA Health from 01/01/2018 to 06/06/2023. Abdominal hernia was identified by clinic encounter ICD-10 codes (K40–K46). Results: There were 41,703 hernias identified among 1,362,440 patients (306.1 per10,000) with a mean age of 62.5 ± 16.1 years, and 57.6% were men. Nearly half (44.7%) of all abdominal hernias were diaphragmatic. There was an approximately equal distribution of the ventral (28.7%) and inguinal (24.3%) hernia. Each hernia type had a different relationship with obesity: The odds of having a ventral hernia increased with BMI in both sexes: BMI 25–29.9 kg/m2 odds ratio (OR) = 1.65, (CI 1.56–1.74); BMI 30–39.9 kg/m2 OR = 2.42 (CI 2.29–2.56), BMI 40–49.9 kg/m2 OR = 2.28 (CI 2.05–2.54) and BMI > = 50 kg/m2 OR = 2.54 (CI 2.03–3.17) all relative to normal BMI. In contrast, the odds of having an inguinal hernia decreased with obesity relative to normal weight [obesity (BMI 30–39.9 kg/m2): OR = 0.60 (CI 0.56–0.65)], morbid obesity (BMI 40–49.9 kg/m2): OR = 0.29 (CI 0.23–0.37). The OR for diaphragmatic hernia peaks with obesity in women and overweight status in men but was found to decrease with morbid obesity [OR = 1.18 (CI 1.07–1.30)]. There was no significant difference between men and women in the prevalence of femoral hernia (men: 0.7/per10,000, women: 0.9/per10,000, p = 0.19). Conclusions: The relationship between hernia and obesity is complex with some hernias decreasing in prevalence as obesity increases. Further research is needed to better understand this paradoxical relationship. [ABSTRACT FROM AUTHOR]

Neuronal ceroid lipofuscinoses (NCLs) belong to a group of inherited neurodegenerative disorders without effective treatments. Though loss-of-function in the MFSD8 gene resulting in a variant late-infantile subtype of NCLs is well documented, its roles remain poorly explored and understood. The results showed an increased cell apoptosis rate after the MFSD8 gene low expression in HUVECs by Flow cytometric analysis. RNA sequencing revealed 367 differentially expressed genes upon the MFSD8 gene overexpression in HUVECs. Bioinformatics analyses revealed that the MFSD8 gene overexpression might be involved in the PI3K/Akt signaling pathway, and interleukin-6 (IL-6), interleukin-1 beta (IL-1B), fibronectin 1 (FN1), fibroblast growth factor 2 (FGF2), toll-like receptor 4 (TLR4), tumor necrosis factor (TNF), and prostaglandin G/H synthase 2 (PTGS2) were the potential hub genes affected by the MFSD8 gene. Gene set enrichment analysis and qRT-PCR assay validation also disclosed that the "Hallmark_Apoptosis" pathway was dramatically enriched in differentially expressed genes. The results revealed that the loss of functional MFSD8 protein indirectly or directly increased the apoptosis of HUVECs, indicating that the expression of the MFSD8 gene was essential for cell survival. The hub genes, including IL-6, IL-1B, FN1, FGF2, TLR4, TNF, and PTGS2, might provide insight into the apoptosis induced by the MFSD8 gene in NCLs. Although many experiments are required to validate these predictions, the results may help investigate the roles of the MFSD8 gene on apoptosis and the corresponding mechanism. [ABSTRACT FROM AUTHOR]

The linear and nonlinear effects of hydrogen isotope species on ion temperature gradient (ITG) instability in the Large Helical Device (LHD) stellarator are studied using radially global gyrokinetic simulation. We found that the coupling range of linear toroidal harmonics depends on the ion mass of the hydrogen isotope. The growth rates of ITG mode are almost the same for H, D, and T plasmas, indicating a gyro-Bohm scaling of ion-mass dependence. The nonlinear electrostatic simulations show that the zonal flow breaks the radially elongated eigenmode structures and reduces the size of the turbulence eddies, which suppresses the turbulence and the ion heat transport in the LHD. The turbulence amplitude without the zonal flow is almost the same for H, D, and T plasmas, while it decreases with increasing ion mass of the hydrogen isotope when the zonal flow is present. The reduction of the turbulent transport with larger ion mass is mostly due to the enhancement of zonal flows by larger ion mass. The ion heat conductivity deviates from the gyro-Bohm scaling for both cases with and without the zonal flow. [ABSTRACT FROM AUTHOR]

Sorghum (Sorghum bicolor) is the fifth largest cereal crop in the world and is an important food and feed crop. However, the understanding of the chloroplast genome of sorghum is limited, especially for some landrace varieties. In this study, the complete chloroplast (cp) genomes of 10 sorghum varieties from southwestern China were assembled and analysed in depth. The genome sizes ranged between 140.644 and 140.814 bp; the b3 variety had the smallest genome size, and the b6, b7 and b8 varieties had the largest. Highly conserved sequences were found among the 10 cp genomes. A total of 136 genes, including 88 protein-coding genes, 40 tRNAs and 8 rRNAs, were found in each cp genome. Comparative genomic analysis revealed that the large single-copy (LSC) region had more SNPs and indels than the inverted repeat (IR) and small single-copy (SSC) regions. Furthermore, some genes, including matK, matK-trnk, psbM-petN, rps12-rpl20, and ccsA, exhibited greater sequence variation than others. Furthermore, phylogenetic analysis revealed that b3 had a distant genetic relationship with the other 9 varieties. Our findings provide valuable information for a deeper understanding of the genetic structure of sorghum germplasm resources globally and provide an important foundation for subsequent genetic improvement of sorghum. [ABSTRACT FROM AUTHOR]

Context. Filament eruption is a common phenomenon in solar activity, but the triggering mechanism is not well understood. Aims. We focus our study on a filament eruption located in a complex nest of three active regions close to a coronal hole. Methods. The filament eruption is observed at multiple wavelengths: by the Global Oscillation Network Group (GONG), the Solar Terrestrial Relations Observatory (STEREO), the Solar Upper Transition Region Imager (SUTRI), and the Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamic Observatory (SDO). Thanks to high-temporal-resolution observations, we were able to analyze the evolution of the fine structure of the filament in detail. The filament changes direction during the eruption, which is followed by a halo coronal mass ejection detected by the Large Angle Spectrometric Coronagraph (LASCO) on board the Solar and Heliospheric Observatory (SOHO). A Type III radio burst was also registered at the time of the eruption. To investigate the process of the eruption, we analyzed the magnetic topology of the filament region adopting a nonlinear force-free-field (NLFFF) extrapolation method and the polytropic global magnetohydrodynamic (MHD) modeling. We modeled the filament by embedding a twisted flux rope with the regularized Biot-Savart Laws (RBSL) method in the ambient magnetic field. Results. The extrapolation results show that magnetic reconnection occurs in a fan-spine configuration resulting in a circular flare ribbon. The global modeling of the corona demonstrates that there was an interaction between the filament and open field lines, causing a deflection of the filament in the direction of the observed CME eruption and dimming area. Conclusions. The modeling supports the following scenario: magnetic reconnection not only occurs with the filament itself (the flux rope) but also with the background magnetic field lines and open field lines of the coronal hole located to the east of the flux rope. This multiwavelength analysis indicates that the filament undergoes multiple magnetic reconnections on small and large scales with a drifting of the flux rope. [ABSTRACT FROM AUTHOR]

We experimentally demonstrated that composites, being effective in optimizing the thermoelectric performance, can also enhance photothermoelectric effects in this work. In detail, we employed an alternating-growth in chemical-vapor-transport to grow the SnSe–SnSe2 composite crystals. The photo-responsivities of SnSe–SnSe2 (atomic-weight-ratio as 44%–56%) composite are comparable to SnSe crystals in the visible band (444 and 532 nm). However, the responsivities of SnSe–SnSe2 have remarkable 27.3% enhancement than those of SnSe crystal at the near-infrared band (1310 and 1550 nm). Supported by optical spectroscopy and theoretical electronic band structure, the enhanced optical responsivity of SnSe–SnSe2 composites is due to the formation of P–N junctions at interfaces between SnSe and SnSe2, leading to more optical transition channels and corresponding optical absorptions in near-infrared band. Our work verifies that hetero-junction formed among constituent compounds in composites is effective in optimizing the photothermoelectric response of thermoelectric materials in certain electromagnetic bands, paving the way to develop photoelectric detection devices. [ABSTRACT FROM AUTHOR]

On 24 April 2023, a Coronal Mass Ejection event caused the solar wind to become sub‐Alfvénic, leading to the development of an Alfvén Wing configuration in the Earth's magnetosphere. Alfvén Wings have previously been observed as cavities of low flow around moons in Jupiter's and Saturn's magnetospheres, but the observing spacecraft did not have the ability to directly measure the Alfvén Wings' current structures. Through in situ measurements made by the Magnetospheric Multiscale spacecraft, the 24 April event provides us with the first direct measurements of current structures during an Alfvén Wing configuration. These structures are observed to be significantly more anti‐field‐aligned and electron‐driven than the typical diamagnetic magnetopause current, indicating the disruption caused to the magnetosphere current system by the Alfvén Wing formation. The magnetopause current is then observed to recover more of its typical, perpendicular structure during the magnetosphere's recovery from the Alfvén Wing formation. Plain Language Summary: The solar wind applies pressure on the Earth's magnetic field, distorting it from a dipole into its compressed dayside and stretched tail configuration. However, this typical structure can be disrupted by eruptive solar events such as Coronal Mass Ejections (CMEs), which may cause the solar wind's pressure to drop low enough that it is no longer able to push the magnetosphere back to form a single unified tail. When this occurs, the tail splits into two separate structures, called Alfvén Wings. While this configuration is rare at Earth, it is common from interactions of the outer planets' magnetosphere's with their moons, where Alfvén Wing configurations have been studied and modeled. However, because the observing spacecraft lacked the necessary instrumentation, we have not yet directly observed the Alfvén Wing current structures. On 24 April 2023, a CME event led to the creation of an Alfvén Wing formation in the Earth's magnetosphere. We observed this event using the Magnetospheric Multiscale spacecraft, which enabled us to make the first direct observations of Alfvén Wing current structures. These currents were found to be mainly parallel to the local magnetic field, in contrast to typical magnetopause currents. Key Points: On 24 April 2023, the Magnetospheric Multiscale (MMS) spacecraft observed an Alfvén Wing formation along the dawn‐flank of Earth's magnetosphereMMS's observations represent the first in situ measurements of Alfvén Wing current structuresThe current structures are found to be primarily anti‐field‐aligned, electron‐driven, and filamentary [ABSTRACT FROM AUTHOR]

Beneficial from the fine lamellar structure, eutectic metallic alloys exhibit good strength-ductility synergy and are often used in high-temperature structural applications. However, such application usually exerts external stress on the material, which could destabilize the lamellar structure and degrade the mechanical properties. In order to unravel the effect of elastic stress on the destabilization process of lamellar structure, herein, we investigated the microstructural evolution of Ni–Sn eutectic lamellae under different elastic stresses at 1073 K. Meanwhile, a mathematical model was established to evaluate the destabilization process by taking both external stress and temperature into consideration. Both experimental results and the mathematical model showed that elastic stress could accelerate the destabilization of eutectic lamellae, and the destabilization time decreases with increasing the elastic stress. In general, the effect of elastic stress on the destabilization of the eutectic lamellae is twofold. In the early stage of destabilization, the elastic stress would generate different elastic energy density between trough and peak, which would cause diffusion of atoms from trough to peak and trigger the destabilization process. Subsequently, the elastic stress acts as a driving force for the destabilization process, with the assistance of interfacial energy. This work could provide guidance for the application of eutectic alloys. [ABSTRACT FROM AUTHOR]

Soil potassium is a vital macronutrient and element for both crops and biogeochemical cycles. However, studies on variety of soil potassium and environmental factors in long term cultivated farmlands are still lack. In this study, both soil properties of topsoil (0-20 cm) and environmental factors of ten soil health monitoring station in China were investigated from 1990 to 2018. Seven learning methods were used to build soil total potassium (TK) prediction model. Results showed that the mean value of soil TK content in 0-20 cm was 15.64±0.09 g·kg-1 with the range of 3.17-31.04 g·kg-1. TK significantly increased with both the increasing of soil pH and elevation, while significantly decreased with the increasing of total organic carbon, organic matters, air temperature, amount of precipitation, humidity, and atmospheric pressure. The order of R2 of soil TK prediction models from low to high was Linear Regression < Support Vector Regression < Decision Tree < Light Gradient Boosting Machine < Random Forest < eXtreme Gradient Boosting < Feedforward neural networks with the highest R2 at 0.91 and the lowest values of RMSE and EF. Soil pH, air temperature, and precipitation could be important environmental factors affecting significantly soil total potassium. Machine learning methods generally showed better performances than that linear regression one. Based on long-term and in-situ monitor of soil properties and environmental factors, a sustainability management strategy for farmlands could come true. [ABSTRACT FROM AUTHOR]

Black cisgender sexually minoritized men (SMM) and transgender women (TW) are subgroups at highest risk of HIV and sexually transmitted infections (STIs) in the US. We sought to identify factors facilitating continued conversations – social reinforcement – surrounding HIV/STI prevention among this subgroup. Participants were recruited in Chicago from 2018 to 2019 from community health spaces. Participants provided information about themselves (level 2) and ⩽5 confidants (level 1). We used multinomial multilevel modeling to identify associations with HIV/STI prevention conversation frequency. A total of 370 participants provided information on 987 confidants (mean = 2.6). We found significantly positive associations between having biweekly or more often HIV/STI prevention conversations and a confidant being a kin family member, older by 15 years or more, racially homophilous, and emotionally close. Future interventions should harness social networks by including components that consider racial homophily, respect for elders, and strong ties, in addition to applying kin family systems interventions approaches and decreasing stigma surrounding HIV/STIs. [ABSTRACT FROM AUTHOR]

The coal mine roller is a key component in the mine belt conveyor system. The work described herein involved a Fe-based clad prepared on a 42CrMo steel roller substrate by laser cladding in order to improve the service life and performance of the coal mine roller. The chemical composition, microstructure, properties, microhardness, wear resistance and salt spray corrosion performance of the laser clad layer and substrate under the optimum process parameters were systematically studied. The results showed that laser scanning speed and laser power mainly affect the width, height and depth of the clad. The process parameters were optimized by a series of orthogonal experiments. The optimal process parameters were a laser power of 1700 W, scanning speed of 6 mm/s and powder feed rate of 15 g/min. The laser clad mainly composed γ-Fe and the compounds of Fe and Cr, such as CrFe4and CrFe19. Along the depth direction of laser clad the microstructure gradually changed from planar crystal and bits of dendrite crystal to equiaxed crystal. The grains at the top of the direction of the laser cladding layer were further refined. The hardness of the laser clad was increased by about 2.2 times that of the substrate. The friction and the loss of weight from wear test and salt spray corrosion of the laser clad show that the weight gain is much smaller than that of the substrate. The experimental results show that the wear resistance and corrosion resistance are improved significantly. [ABSTRACT FROM AUTHOR]

This article presents a study on the synthesis and character of a new organic-inorganic hybrid [4FBzTPP]2[CuBr4] (1) ([4FBzTPP]+ is 4-fluorobenzyltriphenylphosphinium) by XRD, SEM, FTIR and UV-Vis. The XRD analysis showed that the hybrid 1 belongs to the triclinic space group P21 with b = 8.8600(10) Å, c = 16.4867(17) Å, α = 16.639(2)°, β = 96.342(4)°, V = 2415.6(5) Å3, and Z = 2. The hybrid consists of two [4FBzTPP]+ cations and one [CuBr4]2– anion, and the [CuBr4]2– exhibits a twisted tetrahedral coordination geometry with the average bond length between Cu–Br is 2.393 Å. The 3D network structure of 1 is formed by electrostatic terms and other intermolecular interactions. The hybrid material undergoes a direct optical transition and has energy gap values of 1.66 eV and 2.18 eV, indicating its potential as a semiconductor material for optical research. The hybrid material undergoes a direct optical transition and has energy gap values of 1.66 eV and 2.18 eV, showing that the hybrid material is a potential semiconductor material for optical research. In addition, the compound exhibited good antibacterial activity against E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

Background: Information about seasonal variation in the fatty acid (FA) composition of bulk tak milk and its relationship with dietary factors in Taiwan remains to be completed. This study aimed to determine the average FA composition of milk in different seasons and collect dietary information to investigate the relationship between dietary characteristics and lactation performance, including FA concentration in bulk tank milk. Methods: Bulk tank milk samples were collected monthly from 90 dairy farms across Taiwan for two years to capture seasonal variations. Additionally, 36 bulk tank milk samples from three farms were collected monthly from August 2022 to July 2023. Result: Milk production (kg/day), fat (%), crude protein (%), true protein (%), lactose (%) and solids-not-fat (%) were significantly higher in the cold season than in the hot and warm seasons (P<0.05) over the studied period. In contrast, somatic cell counts were significantly lower in the cold season than in the hot and warm seasons (P<0.05). Total saturated FA and C14:0 concentrations were significantly higher in the cold season than in the hot and warm seasons (P<0.05). In contrast, the C18:1 concentration was significantly higher in the hot and warm seasons than in the cold season (P<0.05). However, the C18:0 concentration did not differ significantly by season. Fat and FA concentrations varied significantly among three selected dairy farms (P<0.05). Milk fat only differed significantly between the three farms in the hot season, with Farm B having the lowest milk fat concentration (P<0.05). FA concentrations showed significant seasonal effects at all three farms. These results provide an overview of milk FA variation and identify the critical factors influencing variation in bulk tank milk fat and individual farm FA concentrations: dietary ether extract content and forage choice. [ABSTRACT FROM AUTHOR]

Background and Aims: Climate change is happening and causing severe impact on the sustainability of agroecosystems. We argue that many of the abiotic stresses associated with climate change will be most acutely perceived by the plant at the root-soil interface and are likely to be mitigated at this globally important interface. In this review we will focus on the direct impacts of climate change, temperature, drought and pCO2, on roots and rhizospheres. Methods and Results: We consider which belowground traits will be impacted and discuss the potential for monitoring and quantifying these traits for modelling and breeding programs. We discuss the specific impacts of combined stress and the role of the microbial communities populating the root-soil interface, collectively referred to as the rhizosphere microbiota, in interactions with roots under stress and discuss the plastic responses to stress as a way of adapting plants to climate change. We then go on to discuss the role that modelling has in understanding this complex problem and suggest the best belowground targets for adaptation and mitigation to climate change. We finish by considering where the main uncertainties lie, providing perspective on where research is needed. Conclusion: This review therefore focuses on the potential of roots and rhizosphere to adapt to climate change effects and to mitigate their negative impacts on plant growth, crop productivity, soil health and ecosystem services. [ABSTRACT FROM AUTHOR]

The paper builds on earlier research in which a full Bayesian approach was used to derive crash modification factors (CMFs) from regression models that capture the variability in these CMFs. The approach estimates a non-linear function that reflects the logical reality that the CMF for a given change in a feature's value depends not only on the amount of the change but also on the original value. However, in developing the approach, it was necessary to amalgamate panel data over several years by averaging annual traffic volumes and modeling the summation of annual crash counts. Such aggregation could be problematic if there is significant temporal variability in traffic volumes and crash frequencies, as would be the assumption that there is no site-to-site variation in the effects of independent variables on the crash frequency. The research for this paper examined whether these limitations can materially affect the CMF estimates by using simulated data to introduce substantial temporal and spatial variability in expected crash frequencies. A non-linear model with random effects that captures this variability was developed and compared to the non-linear model with fixed effects. The results show that the parameter estimates and CMFs for freeway median width, the feature used for the case study, were almost identical for the two non-linear approaches. This suggests that the aggregation approach in the earlier research may be adequate for capturing the non-linear safety effects of roadway attributes. The finding has practical importance in the sense that the amalgamation is often necessary when traffic data are not available for each year and also in the sense that when such amalgamation is done, the extent of the temporal variability in traffic volumes and expected crash frequencies is usually unknown. Future studies should expand the investigation to datasets that exhibit temporal variations in some features, such as pavement friction. [ABSTRACT FROM AUTHOR]

The full data set of the Daya Bay reactor neutrino experiment is used to probe the effect of the charged current non-standard interactions (CC-NSI) on neutrino oscillation experiments. Two different approaches are applied and constraints on the corresponding CC-NSI parameters are obtained with the neutrino flux taken from the Huber-Mueller model with a 5% uncertainty. For the quantum mechanics-based approach (QM-NSI), the constraints on the CC-NSI parameters ϵeα and ϵ eα s are extracted with and without the assumption that the effects of the new physics are the same in the production and detection processes, respectively. The approach based on the weak effective field theory (WEFT-NSI) deals with four types of CC-NSI represented by the parameters [εX]eα. For both approaches, the results for the CC-NSI parameters are shown for cases with various fixed values of the CC-NSI and the Dirac CP-violating phases, and when they are allowed to vary freely. We find that constraints on the QM-NSI parameters ϵeα and ϵ eα s from the Daya Bay experiment alone can reach the order O (0.01) for the former and O (0.1) for the latter, while for WEFT-NSI parameters [εX]eα, we obtain O (0.1) for both cases. [ABSTRACT FROM AUTHOR]

During thermonuclear bursts, it is suspected that cooling of the corona by the burst emission may be the cause of hard X-ray deficits. Although such a deficit has been observed in nine sources, it has not been observed from 4U 1608–52, a nearby prolific burster. Therefore, the authenticity and universality of the hard X-ray deficit may be in question. To investigate this suspicion, Insight–HXMT performed cadence observations during the low/hard state of 4U 1608–52 in 2022 September and detected 10 thermonuclear X-ray bursts. Two of these bursts show a double-peaked structure in the soft X-ray band, which could be caused by the high temperature of the burst emission and a marginal photospheric radius expansion (PRE) around the burst peak time. This is indicated by their peak fluxes being up to the Eddington limit and having a large colour factor at the peak of the bursts. A hard X-ray deficit is observed at a significant level during bursts at > 30 keV. Furthermore, the fraction of this deficit shows saturation at 50 per cent for the first eight bursts. This saturation may indicate that the corona is layered and only part of the corona is cooled by the bursts: for example, the part close to the neutron star surface is cooled while the rest remains intact during bursts. This result provides a clue to the geometry of the corona. For example, a possible scenario is that the corona has two forms: a quasi-spheric corona between the neutron star and the disc and a disc corona on both surfaces of the disc. [ABSTRACT FROM AUTHOR]

The current study draws from family systems theory to investigate the relationships between parents' Internet practices, adolescent age (as a proxy for child development), and adolescents' perceptions of parent-adolescent relationship quality. Secondary data analysis of 4,592 U.S. parent-adolescent dyads from a nationally representative cross-sectional survey revealed that when parents reported having more problematic Internet use, adolescents (ages 12–17) reported having worse relationships with their parents. Stricter rules regarding Internet usage were associated with lower parent-adolescent relationship quality. This negative relationship was more pronounced for adolescents 14.55 years old and older. Unexpectedly, having stricter rules about Internet content was related to better parent-adolescent relationship quality; this association was weaker for older adolescents. The findings provide insight into the differences between restrictive Internet mediation practices about time and content, the importance of examining parents' problematic Internet use, and the need for considering children's development when examining the role of media in the family system. [ABSTRACT FROM AUTHOR]

Likelihood-based inference under nonconvex constraints on model parameters has become increasingly common in biomedical research. In this paper, we establish large-sample properties of the maximum likelihood estimator when the true parameter value lies at the boundary of a nonconvex parameter space. We further derive the asymptotic distribution of the likelihood ratio test statistic under nonconvex constraints on model parameters. A general Monte Carlo procedure for generating the limiting distribution is provided. The theoretical results are demonstrated by five examples in Anderson's stereotype logistic regression model, genetic association studies, gene-environment interaction tests, cost-constrained linear regression and fairness-constrained linear regression. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association between oral health status and all‐cause mortality in older adults using prospective cohort study design. Setting and participants: In total, 12 809 adults aged ≥70 years (54.3% females) were participants of the ASPREE Longitudinal Study of Older Persons (ALSOP). Methods: Participants self‐reported the presence of natural teeth and oral health status. The association of self‐reported oral health, edentulism and the integrative measure of the two with all‐cause mortality were explored using the Cox‐regression models adjusted for age, gender, socio‐economic status, health‐related behaviours, weight status, aspirin and polypharmacy. Hazard ratios (HRs) and 95% confidence intervals (CIs) were reported. Results: In total, 22.2% of participants reported edentulism and 13.8% had fair/poor oral health. After adjustment for confounders, risk of all‐cause mortality was higher among those with edentulism (vs. no edentulism) HR (95% CI) 1.43 (1.18, 1.73); and those with edentulism and reporting poor/fair oral health HR (95% CI) 1.69 (1.02, 2.82), or with no edentulism but reporting poor/fair oral health HR (95% CI) 1.46 (1.19–1.80) vs. no edentulism and reporting good/very good/excellent oral health. No association was observed between self‐reported oral health alone and all‐cause mortality. Conclusions: The risk of all‐cause mortality was 69% higher among older adults reporting both edentulism and poor/fair oral health compared with those with teeth and more favourable self‐reported oral health. © 2023 Australian Dental Association. [ABSTRACT FROM AUTHOR]

Species of Pseudocercospora are commonly associated with leaf and fruit spots on diverse plant hosts in sub-tropical and tropical regions. Pseudocercospora spp. have mycosphaerella-like sexual morphs, but represent a distinct genus in Mycosphaerellaceae (Mycosphaerellales, Dothideomycetes). The present study adds a further 29 novel species of Pseudocercospora from 413 host species representing 297 host genera occurring in 60 countries and designates four epitypes and one lectotype for established names. This study recognises 329 species names, with an additional 69 phylogenetic lineages remaining unnamed due to difficulty in being able to unambiguously apply existing names to those lineages. To help elucidate the taxonomy of these species, a phylogenetic tree was generated from multi-locus DNA sequence data of the internal transcribed spacers and intervening 5.8S nuclear nrRNA gene (ITS), partial actin (actA), and partial translation elongation factor 1-alpha (tef1), as well as the partial DNA-directed RNA polymerase II second largest subunit (rpb2) gene sequences. Novel species described in this study include those from various countries as follows: Australia, Ps. acaciicola from leaf spots on Acacia sp., Ps. anopter from leaf spots on Anopterus glandulosus, Ps. asplenii from leaf spots on Asplenium dimorphum, Ps. australiensis from leaf spots on Eucalyptus gunnii, Ps. badjensis from leaf spots on Eucalyptus badjensis, Ps. erythrophloeicola from leaf spots on Erythrophleum chlorostachys, Ps. grevilleae from leaf spots on Grevillea sp., Ps. lophostemonigena from leaf spots on Lophostemon confertus, Ps. lophostemonis from leaf spots on Lophostemon lactifluus, Ps. paramacadamiae from leaf spots on Macadamia integrifolia, Ps. persooniae from leaf spots on Persoonia sp., Ps. pultenaeae from leaf spots on Pultenaea daphnoides, Ps. tristaniopsidis from leaf spots on Tristaniopsis collina, Ps. victoriae from leaf spots on Eucalyptus globoidea. Brazil, Ps. musigena from leaf spots on Musa sp. China, Ps. lonicerae-japonicae from leaf spots on Lonicera japonica, Ps. rubigena leaf spots on Rubus sp. France (Réunion), Ps. wingfieldii from leaf spots on Acacia heterophylla. Malaysia, Ps. musarum from leaf spots on Musa sp. Netherlands, Ps. rhododendri from leaf spots on Rhododendron sp. South Africa, Ps. balanitis from leaf spots on Balanites sp., Ps. dovyalidicola from leaf spots on Dovyalis zeyheri, Ps. encephalarticola from leaf spots on Encephalartos sp. South Korea, Ps. grewiana from leaf spots on Grewia biloba, Ps. parakaki from leaf spots on Diospyros kaki, Ps. pseudocydoniae from leaf spots on Chaenomeles lagenaria, Ps. paracydoniae from leaf spots on Chaenomeles speciosa. Thailand, Ps. acerigena from leaf spots on Acer sp., Ps. tectonigena from leaf spots on Tectona grandis. Epitypes are designated for Cercospora bonjeaneae-rectae, Cercospora halleriae, Ps. eucleae, and an epitype as well as a lectotype for Ps. macadamiae. Results obtained in the present study contribute to a better understanding of the host specificity and distribution in Pseudocercospora spp., many of which represent important pathogens of food or fibre crops, or organisms of quarantine concern. [ABSTRACT FROM AUTHOR]

Texturally and chemically sector-zoned garnet crystals in two contiguous metapelitic rocks from the Danba dome, eastern Tibetan Plateau (SW China) were investigated. A petrographic boundary in one of the rocks (sample 21DB103) separates a thin section into two zones. Whereas one zone containing sector-zoned garnet and fined-grained matrix is enriched in graphite and quartz, the other zone encompasses garnets with relatively regular habit in a coarse-grained matrix poor in graphite and quartz. The two zones are distinct with regards to the chemical compositions of biotite and plagioclase, as well as the major and trace element zoning patterns of garnet. Electron back-scattered diffraction analysis shows that all the investigated garnet crystals in this sample are single crystals. Relatively higher P-T conditions are estimated for the initial growth of sector-zoned garnet (~ 5.0 kbar / ~540 ℃) compared to the regular garnet (~ 3.8 kbar / ~510 ℃) in this rock, possibly indicating that growth of the sector-zoned garnet postdates growth of the regular garnet. Texturally and chemically radial sectors with garnet-quartz intergrowths and irregular sectors of garnet are preserved in the other graphite-rich rock (sample 21DB104). Isopleth thermobarometry applied to the core of the largest garnet crystal exhibiting sector zoning in this sample reveals P-T conditions of initial garnet crystallization (~ 4.4 kbar / ~512 ℃) that deviate far (~ 0.8 kbar/~45 ℃) from equilibrium, potentially indicating significant overstepping required for garnet nucleation. Plagioclase inclusions in garnet display varying trace element abundances, indicating their replacements of different preexisting phases. These results suggest that abundant graphite may play a pivotal role in changing fluid conditions and reducing the solubility of SiO2 to grow sector-zoned garnet, as well as impeding matrix coarsening. Development of sector-zoned core and dodecahedral faces of garnet may be related to rapid growth with changes in crystal morphology. Irregular sectors may have developed through fluid infiltration and local chemical adjustments. [ABSTRACT FROM AUTHOR]

Texturally and chemically sector-zoned garnet crystals in two contiguous metapelitic rocks from the Danba dome, eastern Tibetan Plateau (SW China) were investigated. A petrographic boundary in one of the rocks (sample 21DB103) separates a thin section into two zones. Whereas one zone containing sector-zoned garnet and fined-grained matrix is enriched in graphite and quartz, the other zone encompasses garnets with relatively regular habit in a coarse-grained matrix poor in graphite and quartz. The two zones are distinct with regards to the chemical compositions of biotite and plagioclase, as well as the major and trace element zoning patterns of garnet. Electron back-scattered diffraction analysis shows that all the investigated garnet crystals in this sample are single crystals. Relatively higher P-T conditions are estimated for the initial growth of sector-zoned garnet (~ 5.0 kbar / ~540 ℃) compared to the regular garnet (~ 3.8 kbar / ~510 ℃) in this rock, possibly indicating that growth of the sector-zoned garnet postdates growth of the regular garnet. Texturally and chemically radial sectors with garnet-quartz intergrowths and irregular sectors of garnet are preserved in the other graphite-rich rock (sample 21DB104). Isopleth thermobarometry applied to the core of the largest garnet crystal exhibiting sector zoning in this sample reveals P-T conditions of initial garnet crystallization (~ 4.4 kbar / ~512 ℃) that deviate far (~ 0.8 kbar/~45 ℃) from equilibrium, potentially indicating significant overstepping required for garnet nucleation. Plagioclase inclusions in garnet display varying trace element abundances, indicating their replacements of different preexisting phases. These results suggest that abundant graphite may play a pivotal role in changing fluid conditions and reducing the solubility of SiO2 to grow sector-zoned garnet, as well as impeding matrix coarsening. Development of sector-zoned core and dodecahedral faces of garnet may be related to rapid growth with changes in crystal morphology. Irregular sectors may have developed through fluid infiltration and local chemical adjustments. [ABSTRACT FROM AUTHOR]

The global diversity of fungi has been estimated between 2 to 11 million species, of which only about 155 000 have been named. Most fungi are invisible to the unaided eye, but they represent a major component of biodiversity on our planet, and play essential ecological roles, supporting life as we know it. Although approximately 20 000 fungal genera are presently recognised, the ecology of most remains undetermined. Despite all this diversity, the mycological community actively researches some fungal genera more commonly than others. This poses an interesting question: why have some fungal genera impacted mycology and related fields more than others? To address this issue, we conducted a bibliometric analysis to identify the top 100 most cited fungal genera. A thorough database search of the Web of Science, Google Scholar, and PubMed was performed to establish which genera are most cited. The most cited 10 genera are Saccharomyces, Candida, Aspergillus, Fusarium, Penicillium, Trichoderma, Botrytis, Pichia, Cryptococcus and Alternaria. Case studies are presented for the 100 most cited genera with general background, notes on their ecology and economic significance and important research advances. This paper provides a historic overview of scientific research of these genera and the prospect for further research. [ABSTRACT FROM AUTHOR]

Recently, Andrews introduced separable integer partition classes and analyzed some well-known theorems. In this paper, we investigate partitions with parts separated by parity introduced by Andrews with the aid of separable integer partition classes with modulus 2. We also extend separable integer partition classes with modulus 1 to overpartitions, called separable overpartition classes. We study overpartitions and the overpartition analogue of Rogers–Ramanujan identities, which are separable overpartition classes. [ABSTRACT FROM AUTHOR]

Magnetic field-induced changes in the electrical resistance of materials reveal insights into the fundamental properties governing their electronic and magnetic behavior. Various classes of magnetoresistance have been realized, including giant, colossal, and extraordinary magnetoresistance, each with distinct physical origins. In recent years, extreme magnetoresistance (XMR) has been observed in topological and non-topological materials displaying a non-saturating magnetoresistance reaching 103−108% in magnetic fields up to 60 T. XMR is often intimately linked to a gapless band structure with steep bands and charge compensation. Here, we show that a linear XMR of 80,000% at 15 T and 2 K emerges at the high-mobility interface between the large band-gap oxides γ-Al2O3 and SrTiO3. Despite the chemically and electronically very dissimilar environment, the temperature/field phase diagrams of γ-Al2O3/SrTiO3 bear a striking resemblance to XMR semimetals. By comparing magnetotransport, microscopic current imaging, and momentum-resolved band structures, we conclude that the XMR in γ-Al2O3/SrTiO3 is not strongly linked to the band structure, but arises from weak disorder enforcing a squeezed guiding center motion of electrons. We also present a dynamic XMR self-enhancement through an autonomous redistribution of quasi-mobile oxygen vacancies. Our findings shed new light on XMR and introduce tunability using dynamic defect engineering. Extreme magnetoresistance is characterized by a large and non-saturating magnetoresistance. Typically, it is observed in materials with compensated bandstructures, however, here, Christensen et al demonstrate a large and non-saturating magnetoresistance in a γAl2O3/SrTiO3 heterostructure, which is related to disorder, rather than the materials bandstructure. [ABSTRACT FROM AUTHOR]

Nonsymmorphic compounds have attracted much interest owing to their potential nontrivial electronic states. Here, we grew V1−δSb2 single crystal with a nonsymmorphic space group I4/mcm and studied their de Haas–van Alphen oscillations. Orientation-dependent magnetization showed quantum oscillations, allowing determination of the three-dimensional Fermi surface and Berry phase. Our theoretical calculation implied that VSb2's band structures manifest flat bands along the Γ–X path, Dirac band crossings near the P and N points, and in the Γ–Z direction, and nontrivial surface states along the Γ ¯ – Z ¯ line. However, the inconsistencies in observed and calculated quantum oscillation frequencies suggest that VSb2's band structures cannot nicely account for these electronic properties of our samples. This study reveals the profound impact of V vacancies on VSb2's electronic states, implying the possible topological quantum phase transition via defect engineering. [ABSTRACT FROM AUTHOR]

Support-seeking, a critical and strategic function of close relationships, is increasingly practiced via texting. Guided by attachment theory and an affordance-centric approach, this study investigated to what extent individuals in a romantic relationship would use texting and face-to-face for support-seeking, and what stimulates their interest in mediated support-seeking. A survey of college students in exclusive romantic relationships (N = 211) found that several affordances (i.e., accessibility, the availability of social cues, and conversation control) were associated with varying levels of interest in texting or face-to-face for support-seeking. Both accessibility and the availability of social cues were perceived as less important by avoidant individuals, which was related to a lack of interest in texting and face-to-face interactions for support-seeking. Anxious individuals valued the availability of social cues more, which led to a greater interest in face-to-face interactions when seeking assistance. These findings contribute to a better understanding of support-seeking behavior in today's mediated world. [ABSTRACT FROM AUTHOR]

Context. Thermonuclear bursts, also known as type I X-ray bursts, result from unstable nuclear burning of H/He accreted to the surface of neutron stars, lasting from tens to hundreds of seconds. Thermonuclear bursts have an important impact on accretion environments around the neutron stars, such as their disks and coronas, and are therefore a subject of extensive research. Thermonuclear bursts can be used as probes to gain a deeper understanding of the properties of their disks and coronas. Aims. By analyzing the data from Insight-HXMT and NICER, we can determine the evolution of the significance of the hard shortage in 4U 1636–536 with its spectral state, as well as the evolution of the fraction of deficit with energy. Additionally, we investigate the possible geometry and evolution of the corona in 4U 1636–536 by combining our findings with the results of spectral analysis. Methods. We extracted the light curves from the Insight-HXMT low-energy, medium-energy, and high-energy data and subtracted their pre-burst emission, which allowed us to estimate the significance of the hard shortages during the bursts. By fitting the spectra, the correlation between the persistent spectral parameters and the significance of the hard shortages could be established. The bursts were then grouped according to the spectral state in which they occurred, and the significance of the hard shortages was estimated. These in turn helped to investigate the evolution of the fraction of deficit with energy. Results. We find that during the soft state the significance of possible hard X-ray shortage in bursts is almost zero. However, in the hard state, some bursts exhibit significant shortages (> 3σ), while others do not. We attempt to establish a correlation between the significance of the hard X-ray shortage and the spectral parameters, but the data quality and the limited number of bursts prevent us from finding a strong correlation. For bursts with insignificant shortages in the soft state, the fraction of the deficit remains small. However, in the hard state the fraction of deficit for all bursts increases with energy, regardless of the significance of the shortage of individual bursts. For bursts during the hard state, we investigated the evolution of the fraction of deficit during the bursts by stacking the peaks and decays of the bursts, and find that as the flux of the bursts decreases, the energy corresponding to the maximum of the fraction of deficit becomes progressively higher. Conclusions. We explore the possible geometry and evolution of the corona suggested by the evolution of the fraction of deficit, which is obtained from the spectral and temporal analysis. [ABSTRACT FROM AUTHOR]