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To reduce the number of casualties in explosion accidents, blast-resistant shelters can be used to protect personnel in high-risk areas of petrochemical processing plants. In this work, the deformation behaviours of uncoated and polyurea-coated blast-resistant plates were studied through gas explosion tests. An ANSYS/LS-DYNA model of a polyurea-coated shelter was established, and the dynamic responses of the shelter under various explosion loads were analysed. A series of fuel-air explosion tests were carried out to investigate the explosion resistance of the full-scale shelter. The results showed that compared with the uncoated blast-resistant plate, the deformation of the polyurea-coated blast-resistant plate was significantly reduced. The overall deformation of the shelter was the central depression of the wall and the inward bending of the frame. The damage effect of a typical high-overpressure, low-duration load was greater than that of typical low-overpressure, long-duration load. The shelter remained intact under three repeated explosive loads, with cracks appearing on the inner wall but no collapse or debris splashing. The shock wave attenuation rate of the shelter reached over 90%, which could significantly reduce the number of indoor casualties., (© 2024. The Author(s).)

This article conducts a comprehensive study on the activation characteristics of faults in the mine and analyzes the distribution patterns of the original rock stress field. Through quantitative research and analysis, we determine the partitioning characteristics of tectonic stress in the mine field under the dual effects of fault activation and original rock stress. The study also reveals the significant impact of different fault activation characteristics and different tectonic stress partitions on the stability of roadway surrounding rock. Using the Mohr-Coulomb strength criterion as a foundation, we investigate the mechanisms of fault activation and establish a mathematical model for fuzzy comprehensive evaluation. This model enables us to determine the strength level of fault activation in coal seam 9 of the Limin coal mine and construct a geological structure model. It has realized the transformation of fault activation degree from qualitative evaluation to quantitative evaluation. The stress state analysis software is used to draw the division of tectonic stress dangerous areas under the synergistic effect of fault activation and original rock stress. We then analyze the impact on the stability of roadway surrounding rock in these different hazardous areas. Utilizing the fuzzy comprehensive evaluation method, we take into account the impact of faults on the distribution characteristics of stress fields and the stability of roadway surrounding rock. This approach enables us to more accurately and comprehensively determine the hazardous areas of tectonic stress in the mine field under the dual effects of faults and original rock stress., (© 2024. The Author(s).)

Layered transition metal hydroxides (LTMHs) with transition metal centers sandwiched between layers of coordinating hydroxide anions have attracted considerable interest for their potential in developing clean energy sources and storage technologies. However, two-dimensional (2D) LTMHs remain largely understudied in terms of physical properties and applications in electronic devices. Here, for the first time we report > 20 μm α-Ni(OH) 2 2D crystals, synthesized from hydrothermal reaction. And an edge-on condensation mechanism assisted with the crystal field geometry is proposed to understand the 2D intra-planar growth of the crystals, which is also testified through series of systematic comparative studies. We also report the successful synthesis of 2D Co(OH) 2 crystals (> 40 μm) with more irregular shape due to the slightly distorted octahedral geometry of the crystal field. Moreover, the detailed structural characterization of synthesized α-Ni(OH) 2 are performed. The optical band gap energy is extrapolated as 2.54 eV from optical absorption measurements and the electronic bandgap is measured as 2.52 eV from reflected electrons energy loss spectroscopy (REELS). We further demonstrate its potential as a wide bandgap (WBG) semiconductor for high voltage operation in 2D electronics with a high breakdown strength, 4.77 MV/cm with 4.9 nm thickness. The successful realization of the 2D LTMHs opens the door for future exploration of more fundamental physical properties and device applications., (© 2024. The Author(s).)

This study addresses the limited non-invasive tools for Oral Cavity Squamous Cell Carcinoma (OSCC) survival prediction by identifying Computed Tomography (CT)-based biomarkers to improve prognosis prediction. A retrospective analysis was conducted on data from 149 OSCC patients, including CT radiomics and clinical information. An ensemble approach involving correlation analysis, score screening, and the Sparse-L1 algorithm was used to select functional features, which were then used to build Cox Proportional Hazards models (CPH). Our CPH achieved a 0.70 concordance index in testing. The model identified two CT-based radiomics features, Gradient-Neighboring-Gray-Tone-Difference-Matrix-Strength (GNS) and normalized-Wavelet-LLL-Gray-Level-Dependence-Matrix-Large-Dependence-High-Gray-Level-Emphasis (HLE), as well as stage and alcohol usage, as survival biomarkers. The GNS group with values above 14 showed a hazard ratio of 0.12 and a 3-year survival rate of about 90%. Conversely, the GNS group with values less than or equal to 14 had a 49% survival rate. For normalized HLE, the high-end group (HLE > - 0.415) had a hazard ratio of 2.41, resulting in a 3-year survival rate of 70%, while the low-end group (HLE ≤ - 0.415) had a 36% survival rate. These findings contribute to our knowledge of how radiomics can be used to predict the outcome so that treatment plans can be tailored for patients people with OSCC to improve their survival., (© 2023. The Author(s).)

With the increase of marine activities in the Arctic area, the demand for reliable design of marine structures is growing. Numerous publications can be found regarding simulations of ice action on structures using cohesive element models of the ice. However, previous studies have rarely discussed the influence of structural form, that is, the form of ice-structure interaction interface, on the ice load. Thus, a more comprehensive understanding of the ice load on structures with different interface geometries needs to be explored. In the present paper, three-dimensional finite element models with the cohesive element method are developed to investigate the ice load on different structures. The numerical results are validated based on in-situ testing data and the results of the previous numerical model. Parametric studies considering structure widths, inclination angles, ice velocity as well as structure roughness are conducted to explore the horizontal force and failure process of the ice sheet. The process of ice-structure interaction and ice loads on different structural forms were discussed and simplified diagrams of ice load distribution on the interface were developed., (© 2023. Springer Nature Limited.)

The aim of this study was to explore a novel method to determine the orientation of acetabular prosthesis in total hip arthroplasty (THA) by refering to the anatomical landmarker of acetabular notches. Forty-one normal developmental hips were included in the present study. The acetabulums were reamed according to standard surgical procedures of THA on life-size 3D printing pelvis models. The inferior edge of acetabular cup were placed (1-5) mm proximal and distal to the proximal line of the anterior and posterior acetabular notches (PLAPAN) respectively to determine cup inclination. The inferior edge of acetabular cup were placed (1-5) mm pronating and supinating around the proximal point of acetabular posterior notch (PPAPN) respectively to determine cup anteversion. The pelvis plain radiographs were took and the inclination and anteversion of the acetabular cup at 22 positions were calculated. In the normal developmental hip, the mean inclination of acetabular prothesis were (35.10 ± 3.22)° and (45.90 ± 2.68)° when the inferior edge of the acetabular cup was 3 mm proximal and 1 mm distal to the PLAPAN. The optimal cup inclination could be obtained when the inferior edge of the acetabular cup was 1 mm proximal to the PLAPAN (the mean inclination was (40.71 ± 2.80)°). The mean anteversion of acetabular prothesis were (10.67 ± 4.55)° and (20.86 ± 4.44)° when the inferior edge of the acetabular cup was 1 mm pronating and 1 mm supinating around the PPAPN. The optimal cup anteversion could be obtained when the inferior edge of the acetabular cup was parallel to the PLAPAN (the mean anteversion was (18.00 ± 1.64)°). The inclination and anteversion of acetabular prosthesis could be determined by refering the anatomical landmarks of acetabular notches, which could help orthopedists to install the acetabular prosthesis quickly and safely in THA., (© 2023. The Author(s).)

The cyclic loading frequency (f cyc ) effects on the resilient modulus (M r ) of freezing-thawing coarse-fine mixtures geomaterials (FTCFG) have always been a research hotspot. A series of long-term cyclic triaxial tests were conducted on FTCFG having different fines content (FC) under different number of freeze-thaw cycles (N FT ) to investigate the effect of f cyc and deviator stress amplitude (q cyc ) on the M r of FTCFG. The freezing-thawing cyclic was found to improve the M r of FTCFG. Additionally, M r of FTCFG shown an obviously rate-dependent characteristics. Then three kinetic effects (rate effect, piston effect, and fatigue effect) are discussed in systemically which are related to q cyc , f cyc and moisture holding capacity (w h ). Finally, a rate dependent model of long-term resilient modulus was developed to predict FTCFG materials' resilient moduli as a function of q cyc , f cyc and w h . The comparisons between the calculation and experimental results reveal that the present model describes the M r of FTCFG well., (© 2022. The Author(s).)

This paper presents an experimental investigation on the effect of freeze-thaw cycling on expansive soil slopes with different initial moisture contents. Clay soil from Weifang, China, was remolded and selected to build the expansive soil slope for the indoor slope model tests. A total of five freeze-thaw cycles were applied to the three expansive soil slopes with different moisture contents ranging from 20 to 40%. Variations of the crack developments, displacements, soil pressures and moisture contents of the expansive soil slope with different initial moisture contents during the freeze-thaw cycling were reported and discussed. The results indicate that higher moisture contents can slow the development of cracks and that the soil pressure increases with decreasing temperature. The soil pressure of slope decreases after freeze-thaw cycle, and the change amplitude of soil pressure after freeze-thaw is proportional to water content. The slopes with a moisture content of 20% and 30% shrinks during freezing and expands during thawing, which was named ES-FSTE Model, while the slope with a 40% moisture content shows the opposite behavior. During freeze-thaw cycles, moisture migrates to slope surface. As initial moisture contents increase, the soil heat transfer rate and bearing capacity decreases after five freeze-thaw cycling., (© 2021. The Author(s).)

Sliding liquefaction is considered to be the cause of high-speed and long-distance sliding of some homogeneous loess landslides in western China. However, there is still a lack of necessary experimental research and analysis on the effects of sliding liquefaction on these landslides. In this work, the effects of sliding liquefaction on irrigation-induced, high-speed and long-distance loess landslides on the South Jingyang Tableland area in China are studied by performing large-scale ring shear tests and using the sled mode. The results are as follows. (1) There are two kinds of long-runout sliding modes of loess landslides on the South Jingyang Tableland: sliding along the terrace surface and sliding within the saturated terrace alluvium, which is associated with sliding liquefaction. Both sliding modes can lead to long-runout sliding. (2) There are some differences in the inclination of the sliding surface between the two sliding modes. Based on the inclination of the sliding surface, the corresponding sliding mode can be distinguished. (3) Under the two sliding modes, the large shear mechanical properties of the two-layer soil composed of loess and alluvial sandy silt show significant differences. The friction between the loess and dry terrace alluvium increases with increasing normal stress and shear rate, while the friction between the loess and saturated terrace alluvium presents the opposite trend. The results show that the sliding distances under different sliding modes present opposite trends with the change in sliding speed. (4) Based on the test results from the ring shear tests and the morphological characteristics of the sliding surface, the sliding mode and sliding distance of a loess landslide can be identified and predicted.

A fourth-order compact finite difference scheme was developed to solve the model equation of simulated moving bed, which has a boundary condition that is updated along the calculation process and cannot be described as an explicit function of time. Two different methods, direct method and pseudo grid point method, were proposed to deal with the boundary condition. The high accuracy of the two methods was confirmed by a case study of solving an advection-diffusion equation with exact solution. The developed compact finite difference scheme was then used to simulate the SMB processes for glucose-fructose separation and enantioseparation of 1,1'-bi-2-naphtol. It was found that the simulated results fit well with the experimental data. Furthermore, the developed method was further combined with the continuous prediction method to shorten the computational time and the results showed that, the computational time can be saved about 45%.

For galling aphids and their hosts, tannins are crucial for plant-insect interactions and for protecting the host plant from herbivory. Due to their peculiar chemical characteristics, tannins from plant galls have been used for medical and chemical purposes for more than 2000 years. In this study, hydrolyzable tannin concentrations in galls increased from gall initiation (38.34% on June 21) to maturation (74.79% on August 8), then decreased gradually thereafter (58.83% on October 12). We identified a total of 81 genes (named as GTS1-81) with putative roles in gallotannin biosynthesis and 22 genes (TS1-22) in condensed tannin biosynthesis. We determined the expression profiles of these genes by real-time PCR over the course of gall development. Multiple genes encoding 1-beta-D-glucosyl transferases were identified, which may play a vital role in gallotannin accumulation in plant galls. This study is the first attempt to examine the molecular basis for the regulation of tannin accumulation in insect gallnuts. The differentially expressed genes we identified may play important roles in both tannin biosynthesis and plant-insect interactions.

In this work, we theoretically propose an optical biosensor (consists of a BK7 glass, a metal film, and a graphene sheet) based on photonic spin Hall effect (SHE). We establish a quantitative relationship between the spin-dependent shift in photonic SHE and the refractive index of sensing medium. It is found that, by considering the surface plasmon resonance effect, the refractive index variations owing to the adsorption of biomolecules in sensing medium can effectively change the spin-dependent displacements. Remarkably, using the weak measurement method, this tiny spin-dependent shifts can be detected with a desirable accuracy so that the corresponding biomolecules concentration can be determined.

In order to evaluate the impact of assisted reproductive technology (ART) procedure and individual factors on the sex ratio of singletons and twins at birth after in vitro fertilization (IVF) and intra-cytoplasmic sperm injection (ICSI) treatment in China. We conducted a retrospective cohort study including patients undergoing their first cycle of IVF or ICSI with autologous oocytes from 2001 to 2015. A total of 7410 babies were born from 5832 women with 7410 live birth. The secondary sex ratio (SSR) in singletons was significantly higher than twins (53.97% vs. 50.89%, P = 0.009). The largest disparity was observed in 'thawed blastocyst embryos ICSI' subgroup that SSR was 59.84% in singletons and 42.45% in twins (P = 0.013). Blastocyst transfer was positively associated with elevated SSR when compared to cleavage stage embryos in singletons (Odds Ratio [OR] = 1.17, P < 0.001). In addition, paternal age was significantly associated with SSR (OR = 0.75, P = 0.014). While the decrease of SSR was significantly associated with ICSI when compared to IVF (OR = 0.61, P = 0.046) in twins. Blastocyst transfer increases SSR in comparing with cleavage stage embryos in singletons, while the use of ICSI reduces SSR in twins. Our findings offered important complement for better understanding the underlying determinant of SSR in ART offspring.

This study evaluated the prevalence and factors associated with sleep disturbance in a large cohort of HIV-infected patients across China. A cross-sectional study was conducted among HIV-infected patients on antiretroviral therapy at 20 AIDS clinics. The Pittsburgh Sleep Quality Index was self-administered by subjects. Socio-demographic characteristics, medical history and HIV-related clinical data were collected. 4103 patients had complete data for analysis. Sleep disturbances were observed in 43.1% of patients. Associated factors in multivariable analysis included psychological factors: anxiety (odds ratio [OR], 3.13; 95% confidence interval [CI], 2.44-4.00; P < 0.001), depression (OR, 2.09; 95% CI, 1.70-2.57; P < 0.001), and both anxiety and depression (OR, 5.90; 95% CI, 4.86-7.16; P < 0.001); sociodemographic factors: MSM (OR, 1.26; 95% CI, 1.04-1.52; P = 0.018), being single (OR, 1.45; 95%CI 1.21-1.74; P < 0.001), higher education (OR, 1.25; 95% CI, 1.03-1.53; P = 0.025); and clinical factors: suboptimal adherence (OR,1.51; 95% CI,1.23-1.85; P < 0.001), regimen-switching (OR, 1.94; 95% CI, 1.12-3.35; P = 0.018), and antidepressant use (OR, 1.98; 95% CI, 1.47-2.67; P = 0.044). Prevalence of sleep disturbance is high in this large Chinese cohort. Associated factors appear related to psychological and social-demographic factors. Health workers may consider routinely assessing sleep disturbances among HIV-infected patients, especially in the first three months after HIV diagnosis, and referring for mental health services, which may positively impact adherence to treatment.

The prevalence of cardiac malignant neoplasms in the general population has been shown to be significant higher than what was previously estimated, yet their treatment has remained difficult and effective therapies are lacking. In the current study, we developed a novel thermotherapy in which PEG-functionalized carbon nanotubes were injected into the tumor regions to assist in the targeted delivery of infrared radiation energy with minimal hyperthermic damage to the surrounding normal tissues. In a mouse model of cardiac malignant neoplasms, the injected carbon nanotubes could rapidly induce coagulative necrosis of tumor tissues when exposed to infrared irradiation. In accordance, the treatment was also found to result in a restoration of heart functions and a concomitant increase of survival rate in mice. Taken together, our carbon nanotube-based thermotherapy successfully addressed the difficulty facing conventional laser ablation methods with regard to off-target thermal injury, and could pave the way for the development of more effective therapies against cardiac malignant neoplasms.

The approximate analytical expressions of tripole-mode and quadrupole-mode solitons in (1 + 1)-dimensional nematic liquid crystals are obtained by applying the variational approach. It is found that the soliton powers for the two types of solitons are not equal with the same parameters, which is much different from their counterparts in the Snyder-Mitchell model (an ideal and typical strongly nolocal nonlinear model). The numerical simulations show that for the strongly nonlocal case, by expanding the response function to the second order, the approximate soliton solutions are in good agreement with the numerical results. Furthermore, by expanding the respond function to the higher orders, the accuracy and the validity range of the approximate soliton solutions increase. If the response function is expanded to the tenth order, the approximate solutions are still valid for the general nonlocal case.

Information on maximum grain yield and its attributes are limited for double-season rice crop grown under the subtropical environment. This study was conducted to examine key characteristics associated with high yielding double-season rice crop through a comparison between an integrated crop management (ICM) and farmers' practice (FP). Field experiments were conducted in the early and late seasons in the subtropical environment of Wuxue County, Hubei Province, China in 2013 and 2014. On average, grain yield in ICM was 13.5% higher than that in FP. A maximum grain yield of 9.40 and 10.53 t ha -1 was achieved under ICM in the early- and late-season rice, respectively. Yield improvement of double-season rice with ICM was achieved with the combined effects of increased plant density and optimized nutrient management. Yield gain of ICM resulted from a combination of increases in sink size due to more panicle number per unit area and biomass production, further supported by the increased leaf area index, leaf area duration, radiation use efficiency, crop growth rate, and total nitrogen uptake compared with FP. Further enhancement in the yield potential of double-season rice should focus on increasing crop growth rate and biomass production through improved and integrated crop management practices., Competing Interests: The authors declare no competing financial interests.

Cardiac myxomas are rare but manifested with risk of embolism and often cause unexpected symptoms or sudden death. We retrospectively collected the medical records of patients diagnosed of cardiac myxomas at the cardiac center of our university. Overall 465 patients were included in this study, patients in the embolism group had significantly higher CHA 2 DS 2 -VASc scores (P = 0.005). In embolic group, stroke was recorded in 110 (77.14%) patients, while embolic events in the limbs were observed in 10 (2.15%) and 9(1.93%) developed splenic infarction. Patients in embolism group had older age (P = 0.021) and higher BMI (P  <0.001) than those in non-embolism group. There was no significant difference between two groups in terms of time of mechanical ventilation (P = 0.065), ICU stay (P = 0.053), hospital stay (P = 0.071) and volume of drainage (P = 0.083), blood transfusions (P = 0.060) except that patients with embolic events had significantly higher incidence of postoperative atrial fibrillation (P = 0.032) and lower survival rate (P < 0.001). Furthermore, the CHA 2 DS 2 -VASc score was a significant predictor of embolism in patients with cardiac myxomas (P = 0.015; P = 0.003) and the Kaplan-Meier analysis obtained a higher rate of embolism in patients with higher stratification of CHA 2 DS 2 -VASc scores (P = 0.002). In conclusion, CHA 2 DS 2 -VASc scoring scheme was strongly predictive of stroke and embolic events in patients with cardiac myxomas.

Chlorophyll meters are widely used to guide nitrogen (N) management by monitoring leaf N status in agricultural systems, but the effects of environmental factors and leaf characteristics on leaf N estimations are still unclear. In the present study, we estimated the relationships among SPAD readings, chlorophyll content and leaf N content per leaf area for seven species grown in multiple environments. There were similar relationships between SPAD readings and chlorophyll content per leaf area for the species groups, but the relationship between chlorophyll content and leaf N content per leaf area, and the relationship between SPAD readings and leaf N content per leaf area varied widely among the species groups. A significant impact of light-dependent chloroplast movement on SPAD readings was observed under low leaf N supplementation in both rice and soybean but not under high N supplementation. Furthermore, the allocation of leaf N to chlorophyll was strongly influenced by short-term changes in growth light. We demonstrate that the relationship between SPAD readings and leaf N content per leaf area is profoundly affected by environmental factors and leaf features of crop species, which should be accounted for when using a chlorophyll meter to guide N management in agricultural systems.

While H2N2 viruses have been sporadically isolated from wild and domestic birds, H2N2 viruses have not been detected among human populations since 1968. Should H2N2 viruses adapt to domestic poultry they may pose a risk of infection to people, as most anyone born after 1968 would likely be susceptible to their infection. We report the isolation of a novel influenza A virus (H2N2) cultured in 2013 from a healthy domestic duck at a live poultry market in Wuxi City, China. Sequence data revealed that the novel H2N2 virus was similar to Eurasian avian lineage avian influenza viruses, the virus had been circulating for ≥ two years among poultry, had an increase in α2,6 binding affinity, and was not highly pathogenic. Approximately 9% of 100 healthy chickens sampled from the same area had elevated antibodies against the H2 antigen. Fortunately, there was sparse serological evidence that the virus was infecting poultry workers or had adapted to infect other mammals. These findings suggest that a novel H2N2 virus has been circulating among domestic poultry in Wuxi City, China and has some has increased human receptor affinity. It seems wise to conduct better surveillance for novel influenza viruses at Chinese live bird markets.

Photonic spin Hall effect (SHE) manifesting itself as spin-dependent splitting escapes detection in previous photon tunneling experiments due to the fact that the induced beam centroid shift is restricted to a fraction of wavelength. In this work, we report on the first observation of this tiny effect in photon tunneling via weak measurements based on preselection and postselection technique on the spin states. We find that the spin-dependent splitting is even larger than the potential barrier thickness when spin-polarized photons tunneling through a potential barrier. This photonic SHE is attributed to spin-redirection Berry phase which can be described as a consequence of the spin-orbit coupling. These findings provide new insight into photon tunneling effect and thereby offer the possibility of developing spin-based nanophotonic applications.

Recent developments in the field of photonic spin Hall effect (SHE) offer new opportunities for advantageous measurement of the optical parameters (refractive index, thickness, etc.) of nanostructures and enable spin-based photonics applications in the future. However, it remains a challenge to develop a tunable photonic SHE with any desired spin-dependent splitting for generation and manipulation of spin-polarized photons. Here, we demonstrate experimentally a scheme to realize the photonic SHE tunably by tailoring the space-variant Pancharatnam-Berry phase (PBP). It is shown that light beams whose polarization with a tunable spatial inhomogeneity can contribute to steering the space-variant PBP which creates a spin-dependent geometric phase gradient, thereby possibly realizing a tunable photonic SHE with any desired spin-dependent splitting. Our scheme provides a convenient method to manipulate the spin photon. The results can be extrapolated to other physical system with similar topological origins.