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This study presents a comprehensive three-dimensional finite element modeling and parametric analysis of composite beam-to-column joints in steel–timber composite structures. The investigation encompassed a variety of shear connector configurations, end plate designs, and bolt dimensions, aiming to elucidate their respective influences on the structural performance and behavior of these joints. Through meticulous numerical simulation, this research sought to enhance the understanding of the interactions and load transfer mechanisms within composite connections, thereby contributing to the optimization of design practices in the field of structural engineering. The load–displacement relationship for timber–steel composite joints subjected to monotonic loading was investigated using ABAQUS 6.14 software. This study systematically analyzed the effects of various parameters, including different configurations of shear connectors, end plate thicknesses, and bolt dimensions, on the overall performance of the joints. Through this comprehensive numerical analysis, the research aimed to provide deeper insights into the mechanical behavior and structural integrity of these composite connections under the applied loading conditions. A non-linear finite element model of timber was developed and verified with the results of the experiment in this study. The findings are discussed in detail, highlighting the intricate relationships between the selected parameters and their respective effects on the performance and overall stability of the composite connections. This thorough evaluation aimed to enhance the understanding of how these variables interact within the context of composite joint design and behavior. Finally, design recommendations for composite structures, such as the dimensions of the bolt, end plate thickness, and different sizes of shear connectors are provided. [ABSTRACT FROM AUTHOR]

High-performance miniature surgical instruments play an important role in complicated minimally invasive surgery (MIS). Based on in-depth analysis of the requirements of MIS and the characteristics of the existing minimally invasive surgical instruments, a multiple degrees of freedom (DOF) robotic surgical instrument with decoupled pose was proposed. Firstly, the design concept of the pose decoupling instrument was described in detail, and its physical structure, transmission structure, and mechanical properties were designed and analyzed. A surgical instrument control algorithm based on the master–slave mode was established. Finally, a physical prototype was developed, and its motion ranges of joints, load capacity, and suture operation performance were comprehensively evaluated, which confirmed the effectiveness of the proposed minimally invasive robotic surgical instrument. [ABSTRACT FROM AUTHOR]

In the context of power-line scenarios characterized by complex backgrounds and diverse scales and shapes of targets, and addressing issues such as large model parameter sizes, insufficient feature extraction, and the susceptibility to missing small targets in engineering-vehicle detection tasks, a lightweight detection algorithm termed CER-YOLOv5s is firstly proposed. The C3 module was restructured by embedding a lightweight Ghost bottleneck structure and convolutional attention module, enhancing the model's ability to extract key features while reducing computational costs. Secondly, an E-BiFPN feature pyramid network is proposed, utilizing channel attention mechanisms to effectively suppress background noise and enhance the model's focus on important regions. Bidirectional connections were introduced to optimize the feature fusion paths, improving the efficiency of multi-scale feature fusion. At the same time, in the feature fusion part, an ERM (enhanced receptive module) was added to expand the receptive field of shallow feature maps through multiple convolution repetitions, enhancing the global information perception capability in relation to small targets. Lastly, a Soft-DIoU-NMS suppression algorithm is proposed to improve the candidate box selection mechanism, addressing the issue of suboptimal detection of occluded targets. The experimental results indicated that compared with the baseline YOLOv5s algorithm, the improved algorithm reduced parameters and computations by 27.8% and 31.9%, respectively. The mean average precision (mAP) increased by 2.9%, reaching 98.3%. This improvement surpasses recent mainstream algorithms and suggests stronger robustness across various scenarios. The algorithm meets the lightweight requirements for embedded devices in power-line scenarios. [ABSTRACT FROM AUTHOR]

In this study, the wear characteristics of the die were tested and analyzed through compaction tests, and the distribution of wear depth along the direction toward the extrusion outlet was obtained. A discrete element method (DEM) model of the die's wear process was established. The results show that the severe wear area is located near the stop position of the compression rod, forming a plow-shaped wear area along the extrusion direction, accompanied by fatigue peeling. The wear depth gradually decreases towards the extrusion outlet. The DEM model partially reveals the occurrence of the wear phenomenon, but the particle motion speed deviates from the actual situation. The maximum compression force value range during the DEM compression stage is within the actual maximum compression force value range, and the relative error range of the average maximum compression force is less than 2%. By verifying the formula to calibrate the model, the calibrated model is compared with the actual mold wear, and the predicted value is close to the actual test result. The DEM can be used to explore the wear mechanism and predict the die's wear failure process, laying the foundation for optimizing die wear resistance design. [ABSTRACT FROM AUTHOR]

The crude protein (CP) content is an important determining factor for the quality of alfalfa, and its accurate and rapid evaluation is a challenge for the industry. A model was developed by combining Fourier transform infrared spectroscopy (FTIS) and chemometric analysis. Fourier spectra were collected in the range of 4000~400 cm−1. Adaptive iteratively reweighted penalized least squares (airPLS) and Savitzky–Golay (SG) were used for preprocessing the spectral data; competitive adaptive reweighted sampling (CARS) and the characteristic peaks of CP functional groups and moieties were used for feature selection; partial least squares regression (PLSR) and random forest regression (RFR) were used for quantitative prediction modelling. By comparing the combined prediction results of CP content, the predictive performance of airPLST-cars-PLSR-CV was the best, with an R P 2 of 0.99 and an RMSEP of 0.053, which is suitable for establishing a small-sample prediction model. The research results show that the combination of the PLSR model can achieve an accurate prediction of the crude protein content of alfalfa forage, which can provide a reliable and effective new detection method for the crude protein content of alfalfa forage. [ABSTRACT FROM AUTHOR]

The Tianshan range, a Paleozoic orogenic belt in Central Asia, has undergone multiple phases of tectonic activities characterized by the N–S compression after the early Mesozoic, including the far‐field effects of the Cenozoic Indian–Asian collision. However, there are limited reports on the tectonic deformation and initiation of Triassic intracontinental deformation in the Tianshan range. Understanding this structural context is crucial for interpreting the early intracontinental deformation history of the Eurasian continent during the early Mesozoic. Growth strata and syn‐tectonic sediments provide a rich source of information on tectonic activities and have been extensively used in the studies of orogenic belts. Based on detail fieldwork conducted in this study, the middle–late Triassic Kelamayi Formation of the northern Kuqa Depression in the southern Tianshan fold‐thrust belt has been identified as the typical syn‐tectonic growth strata. The youngest detrital zircon component in two lithic sandstone samples from the bottom and top of the Kelamayi growth strata yielded U‐Pb ages of 223.4 ± 3.1 and 215.5 ± 2.9 Ma, respectively, indicating that the maximum depositional age of the bottom and top of the Kelamayi growth strata is 226–220 and 218–212 Ma. The geochronological distribution of detrital samples from the Early–Middle Triassic and Late Triassic revealed abrupt changes, suggesting a new source supply resulting from tectonic activation in the Tianshan range. The coupling relationship between the syn‐tectonic sedimentation of the Kelamayi Formation and the South Tianshan fold‐thrust system provides robust evidence that the Triassic intracontinental deformation of the South Tianshan range began at approximately 226–220 Ma (during the Late Triassic) and ended at approximately 218–212 Ma. These findings provide crucial constraints for understanding the intraplate deformation in the Tianshan range during the Triassic. [ABSTRACT FROM AUTHOR]

The evergreen tree species Aquilaria sinensis holds significant economic importance due to its specific medicinal values and increasing market demand. However, the unrestricted illegal exploitation of its wild population poses a threat to its survival. This study aims to contribute to the conservation efforts of A. sinensis by constructing a library database of DNA barcodes, including two chloroplast genes (psbA-trnH and matK) and two nuclear genes (ITS and ITS2). Additionally, the genetic diversity and structure were estimated using inter-simple sequence repeats (ISSR) markers. Four barcodes of 57 collections gained 194 sequences, and 1371 polymorphic bands (98.63%) were observed using DNA ISSR fingerprinting. The Nei's gene diversity (H) of A. sinensis at the species level is 0.2132, while the Shannon information index (I) is 0.3128. The analysis of molecular variance revealed a large significant proportion of total genetic variations and differentiation among populations (Gst = 0.4219), despite a relatively gene flow (Nm = 0.6853) among populations, which were divided into two groups by cluster analysis. There was a close genetic relationship among populations with distances of 0.0845 to 0.5555. This study provides evidence of the efficacy and dependability of establishing a DNA barcode database and using ISSR markers to assess the extent of genetic diversity A. sinensis. Preserving the genetic resources through the conservation of existing populations offers a valuable proposition. The effective utilization of these resources will be further deliberated in subsequent breeding endeavors, with the potential to breed agarwood commercial lines. [ABSTRACT FROM AUTHOR]

A comprehensive investigation of elastic and inelastic electron scattering from molecular pyridine is reported using the ab initio R-matrix method with the static exchange plus polarization and close-coupling approximations for incident energies up to 10 eV. The two well-known low-lying 1 2B1 and 1 2A2 shape resonances as well as a 2 2B1 mixed-character resonance compare well with the theoretical and experimental results. We also detect five core-excited resonances (1 2A1, 1 2B2, 3 2B1, 2 2A2, and 4 2B1), which lie above the first electronic excitation threshold. The total elastic cross sections and momentum transfer cross sections agree reasonably with previous reference data. Comparisons of the differential elastic cross sections of pyridine with those measured for benzene, pyrazine, and pyrimidine show remarkable agreement at scattering angles above 40° but behave differently for forward scattering below 40° below 6 eV, due to the dominant effect of the permanent dipole moment on the differential cross section in the low energy region with narrow scattering angles. Inelastic electronic excitation cross sections are presented, showing the influence of core-excited resonances below the ionization threshold for the first time. [ABSTRACT FROM AUTHOR]

In order to investigate the fracturing behavior of rocks under the influence of plasma shock waves, high-voltage pulsed breakdown experiments on red sandstone were conducted at various discharge distances. The crack propagation process of red sandstone specimens was observed by an ultra-high-speed camera, and the influence of discharge distance on the surface crack density of red sandstone under plasma shock wave was discussed. Subsequently, a finite element model, in line with the experimental conditions, was developed using the numerical simulation software LS-DYNA, the simulation and experimental results were compared, and the experimental process was reproduced. The results indicated that under the action of the plasma shock wave, the damage on the two surfaces perpendicular to the discharge channel is mainly radial cracks, while the damage on the four sides parallel to the discharge channel is mainly transverse cracks. As the discharge distance increased, the crack density on the surface of the specimens gradually increased. The numerical simulation results were used to analyze the internal fracturing process of the specimens and the attenuation of stress waves. It was found that as the discharge distance increased, the effective stress generated within the red sandstone samples by the plasma shock waves exhibited an exponential decay, with the peak effective stress near the free surface tending towards stability. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to improve surgical scene perception by addressing the challenge of reconstructing highly dynamic surgical scenes. We proposed a novel depth estimation network and a reconstruction framework that combines neural radiance fields to provide more accurate scene information for surgical task automation and AR navigation. Methods: We added a spatial pyramid pooling module and a Swin-Transformer module to enhance the robustness of stereo depth estimation. We also improved depth accuracy by adding unique matching constraints from optimal transport. To avoid deformation distortion in highly dynamic scenes, we used neural radiance fields to implicitly represent scenes in the time dimension and optimized them with depth and color information in a learning-based manner. Results: Our experiments on the KITTI and SCARED datasets show that the proposed depth estimation network performs close to the state-of-the-art method on natural images and surpasses the SOTA method on medical images with 1.12% in 3 px Error and 0.45 px in EPE. The proposed dynamic reconstruction framework successfully reconstructed the dynamic cardiac surface on a totally endoscopic coronary artery bypass video, achieving SOTA performance with 27.983 dB in PSNR, 0.812 in SSIM, and 0.189 in LPIPS. Conclusion: Our proposed depth estimation network and reconstruction framework provide a significant contribution to the field of surgical scene perception. The framework achieves better results than SOTA methods on medical datasets, reducing mismatches on depth maps and resulting in more accurate depth maps with clearer edges. The proposed ER framework is verified on a series of dynamic cardiac surgical images. Future efforts will focus on improving the training speed and solving the problem of limited field of view. [ABSTRACT FROM AUTHOR]

Aims: To verify the hypothesis that an enriched environment (EE) alleviates sleep deprivation‐induced fear memory impairment by modulating the basal forebrain (BF) PIEZO1/calpain/autophagy pathway. Methods: Eight‐week‐old male mice were housed in a closed, isolated environment (CE) or an EE, before 6‐h total sleep deprivation. Changes in fear memory after sleep deprivation were observed using an inhibitory avoidance test. Alterations in BF PIEZO1/calpain/autophagy signaling were detected. The PIEZO1 agonist Yoda1 or inhibitor GsMTx4, the calpain inhibitor PD151746, and the autophagy inducer rapamycin or inhibitor 3‐MA were injected into the bilateral BF to investigate the pathways involved in the memory‐maintaining role of EE in sleep‐deprived mice. Results: Mice housed in EE performed better than CE mice in short‐ and long‐term fear memory tests after sleep deprivation. Sleep deprivation resulted in increased PIEZO1 expression, full‐length tropomyosin receptor kinase B (TrkB‐FL) degradation, and autophagy, as reflected by increased LC3 II/I ratio, enhanced p62 degradation, increased TFEB expression and nuclear translocation, and decreased TFEB phosphorylation. These molecular changes were partially reversed by EE treatment. Microinjection of Yoda1 or rapamycin into the bilateral basal forebrain induced excessive autophagy and eliminated the cognition‐protective effects of EE. Bilateral basal forebrain microinjection of GsMTx4, PD151746, or 3‐MA mimicked the cognitive protective and autophagy inhibitory effects of EE in sleep‐deprived mice. Conclusions: EE combats sleep deprivation‐induced fear memory impairments by inhibiting the BF PIEZO1/calpain/autophagy pathway. [ABSTRACT FROM AUTHOR]

The objective of the study was to explore the feasibility of a new drug delivery system using laponite (LAP) and cyclic poly(ethylene glycol) (cPEG). Variously shaped and flexible hybrid nanocrystals were made by both the covalent and physical attachment of chemically homogeneous cyclized PEG to laponite nanodisc plates. The size of the resulting, nearly spherical particles ranged from 1 to 1.5 µm, while PEGylation with linear methoxy poly (ethylene glycol) (mPEG) resulted in fragile sheets of different shapes and sizes. When infused with 10% doxorubicin (DOX), a drug commonly used in the treatment of various cancers, the LAP-cPEG/DOX formulation was transparent and maintained liquid-like homogeneity without delamination, and the drug loading efficiency of the LAP-cPEG nano system was found to be higher than that of the laponite-poly(ethylene glycol) LAP-mPEG system. Furthermore, the LAP-cPEG/DOX formulation showed relative stability in phosphate-buffered saline (PBS) with only 15% of the drug released. However, in the presence of human plasma, about 90% of the drug was released continuously over a period of 24 h for the LAP-cPEG/DOX, while the LAP-mPEG/DOX formulation released 90% of DOX in a 6 h burst. The results of the cell viability assay indicated that the LAP-cPEG/DOX formulation could effectively inhibit the proliferation of A549 lung carcinoma epithelial cells. With the DOX concentration in the range of 1–2 µM in the LAP-cPEG/DOX formulation, enhanced drug effects in both A549 lung carcinoma epithelial cells and primary lung epithelial cells were observed compared to LAP-mPEG/DOX. The unique properties and effects of cPEG nanoparticles provide a potentially better drug delivery system and generate interest for further targeting studies and applications. [ABSTRACT FROM AUTHOR]

Chloroplast genomes for 3 Bidens plants endemic to China (Bidens bipinnata Linn., Bidens pilosa Linn., and Bidens alba var. radiata) have been sequenced, assembled and annotated in this study to distinguish their molecular characterization and phylogenetic relationships. The chloroplast genomes are in typical quadripartite structure with two inverted repeat regions separating a large single copy region and a small single copy region, and ranged from 151,599 to 154,478 bp in length. Similar number of SSRs and long repeats were found in Bidens, wherein mononucleotide repeats (A/T), forward and palindromic repeats were the most in abundance. Gene loss of clpP and psbD, IR expansion and contraction were detected in these Bidens plants. It seems that ndhE, ndhF, ndhG, and rpl32 from the Bidens plants were under positive selection while the majority of chloroplast genes were under purifying selection. Phylogenetic analysis revealed that 3 Bidens plants clustered together and further formed molophyletic clade with other Bidens species, indicating Bidens plants might be under radiation adaptive selection to the changing environment world-widely. Moreover, mutation hotspot analysis and in silico PCR analysis indicated that inter-genic regions of ndhD-ccsA, ndhI-ndhG, ndhF-rpl32, trnL_UAG-rpl32, ndhE-psaC, matK-rps16, rps2-atpI, cemA-petA, petN-psbM were candidate markers of molecular identification for Bidens plants. This study may provide useful information for genetic diversity analysis and molecular identification for Bidens species. [ABSTRACT FROM AUTHOR]

Traditional thermal sterilization technology is easy to implement and safe, but it will destroy food nutrition and change food taste. Therefore, people began to turn their attention to non-thermal sterilization. High-voltage pulsed electric field sterilization technology is one of them; it has attracted much attention because of its high efficiency and little damage to food. Different types of loads will cause serious trailing of the pulse falling edge. In view of this situation, this paper proposes a new topology circuit that combines a solid-state switch with a half-bridge Marx generator. It can be used for high-voltage pulsed electric field sterilization. By improving the structure of the classical Marx circuit, the high-voltage pulse power supply of the new topology circuit has the characteristics of steep rising edge and short falling edge delay; does not require isolation inductance or isolation resistance, which solves the isolation problem between the DC charging power supply and the high-voltage terminal; and has a good voltage-clamping function and load adaptability. The working process of the topology circuit under resistive, capacitive and inductive loads and the voltage clamping effect when the solid-state switch does not work properly in the discharge process are analyzed in detail. The power supply is composed of an adjustable DC power supply, five-stage half-bridge Marx generator and control protection circuit. A field programmable gate array (FPGA) is used as the controller to generate control signals, and optical fiber isolation is used to provide control signals for the main loop. The power supply can output a high-voltage square wave pulse with a voltage amplitude of 10 kV, maximum pulse number of 1000 per second, maximum pulse width of 20 μs, pulse rise time of smaller than 300 ns and short pulse drop time, and the repeated voltage amplitude, frequency and pulse width are adjustable, which can meet the requirements of a high-voltage pulse sterilization experiment. [ABSTRACT FROM AUTHOR]

Reconfigurable absorbers have attracted much interest owing to their dynamic reflection manipulation property. In this work, a novel multifunctional reconfigurable absorber, which can be flexibly switched among wideband absorption mode, frequency‐reconfigurable narrowband absorption mode, and amplitude‐controllable absorption mode, is proposed and demonstrated. This absorber employs the graphene layer for tuning its reflection magnitude, while the springs‐using shape memory alloy (SMA) is adopted to support the whole absorber for dynamically controlling absorption frequency through height regulation. The above functionality switching is realized by the bias voltage applied to the graphene layer and the loaded SMA springs. The reconfigurable absorption performance is experimentally verified, and the corresponding results show that such an absorber can generate wideband absorption in the range of 3.6–18 GHz. By tuning the height of the loaded SMA springs, it will be switched to the narrowband absorption state and its absorption peak frequency can be dynamically tuned from 8.7 to 13.5 GHz. When further changing the graphene resistance, the reflection amplitude can be also controlled in both wide‐ and narrow‐band absorption modes. In addition, the absorber also performs well under circumstances of different polarizations, which may have promising prospects in electromagnetic protection and camouflage fields. [ABSTRACT FROM AUTHOR]

Background: To compare the efficacy and safety of laparoscopic cholecystectomy (LC) in the treatment of acute cholecystitis (AC) at different time points after percutaneous transhepatic gallbladder drainage (PTGBD). Methods: PubMed, EMBASE, Cochrane Library, and Web of Science were searched from database inception to 1 May 2022. The last date of search was the May 30, 2022. The Newcastle–Ottawa scale (NOS) was used to conduct quality assessments, and RevMan (Version 5.4) was used to perform the meta-analysis. Results: A total of 12 studies and 4379 patients were analyzed. Compared with the < 2-week group, the ≥ 2-week group had shorter operation time, less intraoperative blood loss, shorter postoperative hospital stay, lower rate of conversion to laparotomy, and fewer complications. There was no statistical difference between the two groups regarding bile duct injury, bile leakage, and total cost. Conclusions: The evidence indicates that the ≥ 2-week group has the advantage in less intraoperative blood loss, minor tissue damage, quick recovery, and sound healing in treating AC. It can be seen that LC after 2 weeks is safe and effective for AC patients who have already undergone PTGBD and is recommended, but further confirmation is needed in a larger sample of randomized controlled studies. [ABSTRACT FROM AUTHOR]

The thrust nappe played an important role in the Mesozoic tectonic evolution of the middle part of the Central Asian Orogenic Belt (CAOB). However, the timing, structural style and kinematic processes of the thrust nappe remain controversial, particularly the detail of the thrust nappe in the Guaizihu region (110 km east of Ejinaq). In this study, we investigate new field mapping, seismic sections, geochronology and low‐temperature thermochronometric dating to provide constraints on the history of this thrust nappe in the Chaheilingashun area (northwestern Guaizihu region). The field mapping, seismic sections and structural analysis reveal that the autochthonous system had developed a series of strong fold structures in the upper Permian strata. The allochthonous system mainly contains Devonian monzogranite (U‐Pb age, ranges from 386.7 to 389.0 Ma) and Meso–Neoproterozoic schists (the maximum depositional age, ∼880 Ma), which were thrust upon the upper Permian strata during Middle to Late Triassic. Based on similar rocks, geochronological dating and the Yagan thrust, we suggest that the postulated root zone of this allochthon might have originated from the Huhetaoergai area (40–60 km northwest of the study area). The geochronological results reveal that the lower age limit of this thrust nappe is constrained by the Lower–Middle Triassic syntectonic sediments (tuffaceous sandstone, ∼247 Ma), which is the sedimentary response of the fold structure., The timing of the termination of this thrust nappe is defined by the cooling age (40Ar/39Ar data, 217–211 Ma) of the Devonian monzogranite and Meso–Neoproterozoic schists. Thus, we consider this thrust event in the study area to potentially have occurred in the period from 247 Ma to 211 Ma, which may represent the tectonic response to the closure of the Paleo‐Asian Ocean. [ABSTRACT FROM AUTHOR]

To provide a quantitative synthesis of studies on the relationship between vision impairment (VI) and cognitive outcomes in older adults. A systematic search was undertaken of relevant databases for original articles published before April 2020. Random effect models were used to obtain pooled estimates of the associations between VI and cognitive outcomes (cognitive impairment and dementia) with subgroup analyses of VI measures, cross-sectional associations of VI with cognitive impairment, and longitudinal associations of baseline VI with incident cognitive impairment and dementia. Potential sources of heterogeneity were explored by meta-regression. Publication bias was evaluated with Egger's test. Sixteen studies including 76,373 participants were included in this meta-analysis, with five cross-sectional studies and eleven longitudinal studies. There was a significantly increased risk of cognitive outcomes with VI identified by subjective measures (odds ratio (OR)=1.63; 95% confidence interval (CI): 1.26–1.99) and objective measures (OR = 1.59; 95% CI: 1.40–1.78). The odds of baseline cognitive impairment were 137% higher in older adults with VI compared with those without VI (OR = 2.37, 95% CI: 1.84–3.03) at baseline. Compared with older adults without VI at baseline, those with baseline VI had a higher relative risk (RR) of incident cognitive impairment (RR = 1.41; 95% CI: 1.31–1.51) and dementia (RR = 1.44, 95% CI: 1.19–1.75). VI was associated with increased risks of cognitive impairment and dementia across cross-sectional and longitudinal studies. Additional research and randomized clinical trials are warranted to examine the implications of treatment for VI, such as wearing glasses and cataract surgery, to avoid cognitive impairment and dementia. [ABSTRACT FROM AUTHOR]

Ginsenosides have poor oral bioavailability and undergo rapid biological transformation in the complex gastrointestinal environment. Most studies on the metabolism of ginsenosides have focused on gut bacteria, yet gastric juice remains a nonnegligible factor. Metabolic profiles of ginsenoside monomers formed in artificial gastric juice were separately investigated and qualitatively identified using ultra‐high‐pressure liquid chromatography coupled with linear ion trap‐Orbitrap mass spectrometry (UHPLC‐LTQ‐Orbitrap MSn). A common pattern of their metabolic pathways was established, showing that ginsenosides were transformed via deglycosylation, hydration, and dehydration pathways. Two major structure types, 20(S), 20(R)‐protopanaxatriols and 20(S), 20(R)‐protopanaxadiols, basically shared similar transformation pathways and yielded deglycosylated, hydrated, and dehydrated products. Fragmentation patterns of major ginsenosides were also discussed. Consequently, gastric juice, as the primary link in ginsenoside metabolism and as important as the intestinal flora, produces considerable amounts of degraded ginsenosides, providing a partial explanation for the low bioavailabilities of primary ginsenosides. [ABSTRACT FROM AUTHOR]

Background: Species in genus Amomum always have important medicinal and economic values. Classification of Amomum using morphological characters has long been a challenge because they exhibit high similarity. The main goals of this study were to mine genetic markers from cp genomes for Amomum species identification and discover their evolutionary history through comparative analysis. Results: Three species Amomum villosum, Amomum maximum and Amomum longipetiolatum were sequenced and annotated for the complete chloroplast (cp) genomes, and the cp genomes of A. longipetiolatum and A. maximum were the first reported. Three cp genomes exhibited typical quadripartite structures with 163,269-163,591 bp in length. Each genome encodes 130 functional genes including 79 protein-coding, 26 tRNAs and 3 rRNAs genes. 113-152 SSRs and 99 long repeats were identified in the three cp genomes. By designing specific primers, we amplified the highly variable loci and the mined genetic marker ccsA exhibited a relatively high species identification resolution in Amomum. The nonsynonymous and synonymous substitution ratios (Ka/Ks) in Amomum and Alpinia showed that most genes were subjected to a purifying selection. Phylogenetic analysis revealed the evolutionary relationships of Amomum and Alpinia species and proved that Amomum is paraphyletic. In addition, the sequenced sample of A. villosum was found to be a hybrid, becoming the first report of natural hybridization of this genus. Meanwhile, the high-throughput sequencing-based ITS2 analysis was proved to be an efficient tool for interspecific hybrid identification and with the help of the chloroplast genome, the hybrid parents can be also be determined. Conclusion: The comparative analysis and mined genetic markers of cp genomes were conducive to species identification and evolutionary relationships of Amomum. [ABSTRACT FROM AUTHOR]

Purpose: Automatic image segmentation of surgical instruments is a fundamental task in robot-assisted minimally invasive surgery, which greatly improves the context awareness of surgeons during the operation. A novel method based on Mask R-CNN is proposed in this paper to realize accurate instance segmentation of surgical instruments. Methods: A novel feature extraction backbone is built, which could extract both local features through the convolutional neural network branch and global representations through the Swin-Transformer branch. Moreover, skip fusions are applied in the backbone to fuse both features and improve the generalization ability of the network. Results: The proposed method is evaluated on the dataset of MICCAI 2017 EndoVis Challenge with three segmentation tasks and shows state-of-the-art performance with an mIoU of 0.5873 in type segmentation and 0.7408 in part segmentation. Furthermore, the results of ablation studies prove that the proposed novel backbone contributes to at least 17% improvement in mIoU. Conclusion: The promising results demonstrate that our method can effectively extract global representations as well as local features in the segmentation of surgical instruments and improve the accuracy of segmentation. With the proposed novel backbone, the network can segment the contours of surgical instruments' end tips more precisely. This method can provide more accurate data for localization and pose estimation of surgical instruments, and make a further contribution to the automation of robot-assisted minimally invasive surgery. [ABSTRACT FROM AUTHOR]

Protein signaling complexes play important roles in prevention of several cancer types and can be used for development of targeted therapy. The roles of signaling complexes of phosphodiesterase 3B (PDE3B) and Rap guanine nucleotide exchange factor 3 (RAPGEF3), which are two important enzymes of cyclic adenosine monophosphate (cAMP) metabolism, in cancer have not been fully explored. In the current study, a natural product Kaempferol‐3‐O‐(3′′,4′′‐di‐E‐p‐coumaroyl)‐α‐L‐rhamnopyranoside designated as KOLR was extracted from Cinnamomum pauciflorum Nees leaves. KOLR exhibited higher cytotoxic effects against BxCP‐3 pancreatic cancer cell line. In BxPC‐3 cells, the KOLR could enhance the formation of RAPGEF 3/ PDE3B protein complex to inhibit the activation of Rap‐1 and PI3K‐AKT pathway, thereby promoting cell apoptosis and inhibiting cell metastasis. Mutation of RAPGEF3 G557A or low expression of PDE3B inactivated the binding action of KOLR resulting in KOLR resistance. The findings of this study show that PDE3B/RAPGEF3 complex is a potential therapeutic cancer target. [ABSTRACT FROM AUTHOR]

A Mesoproterozoic granite covering about 5 km2 is firstly recognized in the Zhusileng area, which is located between the northern Alxa Block and the South Gobi microcontinent. New geochronological data from this area provide new insight for understanding the Precambrian crustal evolution of the middle segment of the southern Central Asian Orogenic Belt (CAOB). Based on the crystal shapes, internal textures, and high Th/U ratios, the zircons from this Mesoproterozoic granite are interpreted as magmatic origin. Meanwhile, LA‐ICP‐MS zircon U–Pb dating shows that it was emplaced at 1458 ± 7.5 Ma. Published geochronological data and Sr–Nd isotopic compositions of igneous rocks from the Zhusileng area and its vicinity are also compiled in this study. The Late Palaeozoic granitoids from the Zhusileng area have strongly negative εNd(t) values (−0.1 to −10.8), high (87Sr/86Sr)i (0.69657–0.73423) and old Nd model ages (0.9–1.8 Ga), suggesting the existence of Precambrian microcontinent in the Zhusileng area. Furthermore, the statistical analysis (or isotopic mapping) of Sr–Nd isotopic compositions of Palaeozoic granitoids from the middle segment of the southern CAOB also displays similar εNd(t) values and relatively old Nd model ages along the Hanshan Block, Zhusileng, Tsaggan Uul terrane, and Hutag Uul terrane. Therefore, we propose that those units may share a common basement during Mesoproterozoic to Early Neoproterozoic. [ABSTRACT FROM AUTHOR]

Electron collision cross-sections of c-C4F8 were investigated at low energies by using the R-matrix method. The static exchange (SE), static exchange with polarization (SEP), and close-coupling (CC) models of the R-matrix method were used for the calculation of the scattering cross-section. The shape resonance was detected with all the models at around 3~4 eV, and a Feshbach resonance was detected with the SEP model at 7.73 eV, in good agreement with the previous theoretical calculation. The resonance detected was also associated with the experimental dissociative electron attachment of c-C4F8, which displayed the resonances at the same energy range. The cross-sections calculated are important for plasma modeling and applications. [ABSTRACT FROM AUTHOR]

The root of Reynoutria multiflora Thunb. Moldenke (RM, syn.: Polygonum multiflorum Thunb.) has been widely used in TCM clinical practice for centuries. The raw R. multiflora (RRM) should be processed before use, in order to reduce toxicity and increase efficiency. However, the content of trans-2, 3, 5, 4′-tetrahydroxystilbene-2-O-β-D-glucopyranoside (trans-THSG), which is considered to be the main medicinal ingredient, decreases in this process. In order to understand the changes of stilbene glycosides raw R. multiflora (RRM) and processed R. multiflora (PRM), a simple and effective method was developed by ultra high performance liquid chromatography tandem quadrupole/electrostatic field orbitrap high-resolution mass spectrometry (UHPLC-Q-Exactive plus orbitrap MS/MS). The content and quantity of stilbene glycosideshave undergone tremendous changes during the process. Seven parent nucleus of stilbene glycosides and 55 substituents, including 5-HMF and a series of derivatives, were identified in PM. 146 stilbene glycosides were detected in RRM, The number of detected compounds increased from 198 to 219 as the processing time increased from 4 to 32 h. Among the detected compounds, 102 stilbene glycosides may be potential new compounds. And the changing trend of the compounds can be summarized in 3 forms: gradually increased, gradually decreased, first increased and then decreased or decreased first. The content of trans-THSG was indeed decreased during processing, as it was converted into a series of derivatives through the esterification reaction with small molecular compounds. The clarification of secondary metabolite group can provide a basis for the follow-up study on the mechanism of pharmacodynamics and toxicity of PM, and for screening of relevant quality markers. [ABSTRACT FROM AUTHOR]

Water quality and quantity should be paid more attention in regions with arid climate and thick vadose zones since the limited groundwater cannot be replenished rapidly once polluted. This study focused on the Loess Plateau of China to investigate the geochemical mechanism affecting groundwater chemistry and to calculate contribution rates of multiple sources to groundwater solutes. We employed multiple methods (diagrams, bivariate analyses, hierarchical cluster analysis (HCA), sodium adsorption ratio (SAR), water quality index (WQI), correlation analysis, and forward model) for the above purposes. We collected 64 groundwater samples in the thick loess deposits in June 2018 (flood season) and April 2019 (dry season). The average concentrations of cation were in the order of Ca2+ > Na+ > Mg2+ > K+ in the flood season, and Na+ > Ca2+ > Mg2+ > K+ in the dry season. The order of anions contents in the flood season and the dry season were HCO3- > SO42- > Cl- > NO3-. The major hydrochemical facies were Ca-HCO3 and Ca·Mg-HCO3 in the flood season and Na·Ca-HCO3·SO4 and Na-HCO3 in the dry season, respectively. Most of the groundwater (95% in the flood season and 96% in the dry season) was suitable for drinking, and the overall water quality was acceptable for irrigation. Mineral dissolution and cation exchange were important natural processes affecting groundwater chemistry. The forward model showed that the contribution of atmospheric input, anthropogenic input, evaporite dissolution, silicate weathering, and carbonate weathering to solutes in groundwater was 2.3±1.5%, 5.0±7.1%, 19.3±21.4%, 42.8±27.3%, and 30.6±27.1% in the flood season, and 9.1±6.4%, 3.4±5.2%, 20.3±15.9, 56.6±23.2%, and 10.7±15.4% in the dry season, respectively. Obviously, silicate and carbonate weathering contribute the most to groundwater chemistry in the flood season, while silicate weathering and evaporite dissolution contribute the most in the dry season. Although the overall contribution of anthropogenic inputs was insignificant, it was the dominant source of solutes for local groundwater. This study provides fundamental information for water management in arid areas. [ABSTRACT FROM AUTHOR]

Purpose: Stereo vision can provide surgeons with 3D images and reduce the difficulty of operation in robot-assisted surgery. In natural orifice transluminal endoscopic surgery, distortions of the stereoscopic images could be induced at different observation depths. This would increase the risk of surgery. We proposed a novel camera to solve this problem. Methods: This study integrated the camera calibration matrix and the geometric model of stereoscopic system to find the cause of distortion. It was found that image distortions were caused by inappropriate disparity, and this could be avoided by changing the camera baseline. We found the relationship between camera baseline and observation depth with the model. A variable baseline stereoscopic camera with deployable structure was designed to achieve this requirement. The baseline could be adjusted to provide appropriate disparity. Results: Three controlled experiments were conducted to verify the stereo vision of the proposed camera at different observation depths. No significant difference was observed in the completion time. At the observation depths of 30 mm and 90 mm, the number of errors apparently decreased by 62.90% and 51.06%, respectively. Conclusions: The significant decrease in number of errors shows that the proposed camera has a better stereo vision than a regular camera at both small and large observation depths. It can produce more accurate stereoscopic images at any depth. This will further improve the safety of robot-assisted surgery. [ABSTRACT FROM AUTHOR]

We examined formulating a new antifungal agent, posaconazole (POS) and its derivatives, with different molecular vehicles. Several combinations of drug and carrier molecules were synthesized, and their antifungal activities were evaluated against Aspergillus fumigatus. Posaconazole and four of its derivatives were conjugated to either generation 5 (G5) dendrimers or partially modified G5 dendrimers. The in vitro antifungal activities of these compounds suggest that conjugates with specific chemical linkages showed better fungistatic activity than direct conjugates to POS. In particular, a polyethylene glycol (PEG)-imidazole modified G5 dendrimer demonstrated improved antifungal efficacy relative to the parent G5 molecule. Further studies were then conducted with POS derived molecules coupled to PEG-imidazole modified G5 dendrimers to achieve a highly soluble and active conjugate of POS. This conjugated macromolecule averaged 23 POS molecules per G5 and had a high solubility with 50 mg/mL, which improved the molar solubility of POS from less than 0.03mg/mL to as high as 16mg/mL in water. The primary release profile of the drug in human plasma was extended to over 72 h, which is reflected in the in vitro inhibition of A. fumigatus growth of over 96 h. These POS-polymer conjugates appear to be novel and efficient antifungal agents. [ABSTRACT FROM AUTHOR]

Background: Bungarus multicinctus, from which a classical Chinese medicine is produced, is known as the most venomous land snake in the world, but the chromatin organization and transcription factor activity during venom replenishment progress have not been explored yet. This study aimed to determine the roles of chromatin structure in toxin activity via bioinformatics and experimental validation. Methods: Chromosome conformation capture (Hi-C) analysis was used to examine interactions among chromosomes and identify different scales of chromatin during envenomation in B. multicinctus. Correlations between epigenetic modifications and chromatin structure were verified through ChIP-seq analysis. RNA-seq was used to validate the influence of variation in chromatin structure and gene expression levels on venom production and regulation. Results: Our results suggested that intra-chromosomal interactions are more intense than inter-chromosomal interactions among the control group, 3-day group of venom glands and muscles. Through this, we found that compartmental transition was correlated with chromatin interactions. Interestingly, the up-regulated genes in more compartmental switch regions reflect the function of toxin activity. Topologically associated domain (TAD) boundaries enriched with histone modifications are associated with different distributions of genes and the expression levels. Toxin-coding genes in the same loop are highly expressed, implying that the importance of epigenetic regulation during envenomination. On a smaller scale, the epigenetic markers affect transcriptional regulation by controlling the recruitment/inhibition of transcription initiation complexes. Conclusions: Chromatin structure and epigenetic modifications could play a vital status role in the mechanisms of venom regulation in B. multicinctus. [ABSTRACT FROM AUTHOR]

The root of Reynoutria multiflora (Thunb.) Moldenke (syn: Polygonum multiflorum Thunb.) is a distinguished herb that has been popularly used in traditional Chinese medicine. The raw Reynoutria multiflora (RRM) should be processed by steaming before use, and the processing time is not specified in the processing specification. Our previous studies showed that the efficacy and toxicity of processed Reynoutria multiflora (PRM) at different processing times were inconsistent. A comprehensive identification method was established in this study to find a quality marker of raw Reynoutria multiflora (RRM) and processed Reynoutria multiflora (PRM) with different processing times. Metabolomics based on ultra-high-performance liquid chromatography tandem quadrupole/electrostatic field orbitrap high-resolution mass spectrometry (UHPLC-Q-Exactive plus orbitrap MS/MS) was used in this study. Using the CD.2 software processed database, multivariate statistical analysis methods coupled with cluster analysis and heatmap were implemented to distinguish between RRMs and PRMs with different processing times. The results showed that RRM and PRMs processed for 4, 8, 12, and 18 h cluster into group 1, and PRM processed for 24 and 32 h into group 2, indicating that it can effectively distinguish between the two groups and twenty potential markers, made the highest contributions to the observed chemical differences between two groups. Among them, tetrahydroxystilbene-O-hexoside-O-galloyl and sucrose can be used to identify PRM processed for 24 h. Therefore, the properties of RRM changed after 24 h of processing, and the quality markers were screened to distinguish RRM and PPM. It can also be used as an important control technology for the processing of RM, which has wide application prospects. [ABSTRACT FROM AUTHOR]

Although clinically approved hepatitis B virus (HBV) polymerase inhibitors (lamivudine‐3TC, entecavir, etc.) serve as effective therapeutics, the virus can easily generate resistance to them. Therefore, the treatment of HBV infection remains a public health problem. Numerous studies have shown that natural products have prospective anti‐HBV activity. The purpose of this study was to isolate and extract des(rhamnosyl) verbascoside from Lindernia ruellioides (Colsm.) Pennell and explore its anti‐HBV and hepatoprotective effects. Anti‐HBV activity was evaluated in HepG2.2.15 cells, a human hepatocellular carcinoma cell line with HBV‐stable infection, and its protective effect was evaluated in HL‐7702 cells, a normal human liver cell line. HepG2.2.15 cells maintained normal growth morphology within the selected concentration range of des(rhamnosyl) verbascoside. It also inhibited the expression of HBV antigens and HBV DNA in a dose‐ and time‐dependent manner in vitro. Further, western blot experiments showed that it could downregulate HBV X protein (HBx) expression in a dose‐dependent manner. In the H2O2‐induced hepatocyte injury model, the cell‐survival rate of the HL‐7702 cells with the highest drug dose reached 85.25%, which was significantly improved compared with that of the model group. Most of the cells returned to normal morphology, showing polygonal or fusiform structures. Thus, it may be stated that des(rhamnosyl) verbascoside exhibits anti‐HBV activity and hepatoprotective effects in vitro and may exert an anti‐HBV effect via antigen inhibition, HBV DNA secretion, and HBx protein expression. [ABSTRACT FROM AUTHOR]

The Dirac–Weyl equation characterized quasi-particles in the T3 lattice are studied under external magnetic field using the generalized uncertainty principle (GUP). The energy spectrum of the quasi-particles is found by the Nikiforov–Uvarov method. Based on the energy spectrum obtained, the thermodynamic properties are given, and the influence of the GUP on the statistical properties of systems is discussed. The results show that the energy and thermodynamic functions of massless Dirac–Weyl fermions in the T3 lattice depend on the variation of the GUP parameter. [ABSTRACT FROM AUTHOR]

Background: Lettuce (Lactuca sativa L.), one of the most economically important leaf vegetables, exhibits early bolting under high-temperature conditions. Early bolting leads to loss of commodity value and edibility, leading to considerable loss and waste of resources. However, the initiation and molecular mechanism underlying early bolting induced by high temperature remain largely elusive. Results: In order to better understand this phenomenon, we defined the lettuce bolting starting period, and the high temperature (33 °C) and controlled temperature (20 °C) induced bolting starting phase of proteomics is analyzed, based on the iTRAQ-based proteomics, phenotypic measurement, and biological validation by RT-qPCR. Morphological and microscopic observation showed that the initiation of bolting occurred 8 days after high-temperature treatment. Fructose accumulated rapidly after high-temperature treatment. During initiation of bolting, of the 3305 identified proteins, a total of 93 proteins exhibited differential abundances, 38 of which were upregulated and 55 downregulated. Approximately 38% of the proteins were involved in metabolic pathways and were clustered mainly in energy metabolism and protein synthesis. Furthermore, some proteins involved in sugar synthesis were differentially expressed and were also associated with energy production. Conclusions: This report is the first to report on the metabolic changes involved in the initiation of bolting in lettuce. Our study suggested that energy metabolism and ribosomal proteins are pivotal components during initiation of bolting. This study could provide a potential regulatory mechanism for the initiation of early bolting by high temperature, which could have applications in the manipulation of lettuce for breeding. [ABSTRACT FROM AUTHOR]

A comprehensive study of electron collisions with the X1Σg+ ground state as well as the metastable A3Σu+ and a1Πg excited states of the N2 molecule is reported using the fixed-nucleus R-matrix method. Integral elastic scattering and electronic excitation cross sections from the X1Σg+ ground state to the eight lowest electronic states, A3Σu+, B3Πg, W3Δu, B′3Σu−, a1Πg, a′1Σu−, w1Δu and C3Πu, overall agree well with the available experimental and theoretical results although updates of some recommended values are suggested. Accurate electron impact electronic transition cross sections starting from the A3Σu+ and a1Πg metastable excited states are reported. The total summed electronic transition cross sections from the a1Πg state is dominant: an order of magnitude higher than those of the X1Σg+ ground state. The de-excitation cross sections generally show a downward trend with increasing incident electron energy, which is different from the elastic and electronic excitation cross sections which generally increase with collision energy. There is a prominent 2Πu symmetry resonance peak at 2.8 eV for electronic de-excitation scattering of a1Πg → B3Πg, which significantly contributes to the total summed cross sections from the a1Πg excited state. The present results provide a new insight which will aid understanding of electron spectra in the atmosphere of the Earth and Titan. [ABSTRACT FROM AUTHOR]

Patrinia monandra C. B. Clarke is traditionally used for the treatment of inflammation, typhoid fever, injuries due to falls, abdominal pain, malaria, and acute appendicitis ulcers in China and Korea. In this study, the complete chloroplast genome of P. monandra was sequenced using the Illumina HiSeq X-Ten platform. It had a circular shape and a length of 158,940 bp, with 38.51% GC content. It contained a large single-copy region of 87,641 bp, a small single-copy region of 12,807 bp, and two inverted repeat regions of 29,246 bp. In total, 128 different genes, including 83 protein-coding genes, 37 distinct tRNA genes, and eight rRNA genes, were identified. Maximum-likelihood phylogenomic analysis showed that P. monandra is closely related to Patrinia scabiosifolia and Patrinia villosa in the Valerianaceae family. There were 4535 variable sites, 157,354 conserved sites, and 3085 singleton sites in the six Patrinia chloroplast genomes. [ABSTRACT FROM AUTHOR]

UV screening is very important for the prevention of skin cancer and the elongation of the lifetime of organic/polymeric stuff. To overcome the main problems of poor hydrophilicity and easy leakage of organic UV absorbents, water‐dispersible Au(I)‐thiolate nanosheets have been studied as a new type of UV absorbents. The results show that Au(I)‐thiolate nanosheets have i) very high molar absorption coefficients (>15000 mol/L.cm), ii) comparable or superior photostability to typical organic UV absorbents, and iii) high transparency and nearly no leakage in polymer matrix. So far, no other UV absorbents have been reported to have all the above good performances simultaneously. The transparent and colorless Au(I)‐thiolate/polymer thin films can effectively block UV light, and such a material will surely extend the types and the application scenarios of UV absorbents. [ABSTRACT FROM AUTHOR]

Recently, polymer dots (Pdots) possessing conjugated structures have attracted the attention of researchers for use as photocatalysts for H2 evolution reactions. Herein, soluble Pdots (ca. 30 nm) based on the semiconducting polymer poly(9,9-dioctylfluorene) (PFO) were introduced as a photocatalyst for photodegradation activity and light-driven hydrogen generation by a nanoprecipitation method. A photodegradation activity study of these Pdots (PFO-Pdots) with methylene blue (MB) showed a good ability to degrade MB in aqueous solution under simulated light. Moreover, the PFO-Pdots exhibited a good H2 production rate up to 1.20 ± 0.04 mmol h−1 g−1 without platinum or rhodium as a cocatalyst. According to the I–V curves and transient photocurrent response study, it was obvious that a significant photocurrent of the PFO-Pdots was generated under light irradiation. The low recombination rate of the photogenerated carriers and shortened charge diffusion path led to a good photocatalytic H2 evolution rate. These phenomena suggested that the conjugated Pdots only composed of C, H, and O elements had good photocatalytic activity, and it was a powerful supplement to existing polymer photocatalytic systems. Moreover, PFO-Pdots had better photocatalytic activity in water than pure PFO. This study shows that PFO-Pdots or conjugated Pdots may be promising candidates in the field of photocatalysis in the future. [ABSTRACT FROM AUTHOR]

The Eastern Kunlun arc activities were interrupted by repeated continent–continent collision followed by ocean opening along the older suture zones previous created in the Neoproterozoic. The first report of the later Devonian‐early Carboniferous arc magmatism has played a vital role in constraining the evolution of the Eastern Kunlun Orogen. We undertook zircon U–Pb dating, Hf isotopic compositions, whole‐rock geochemical and Nd–Sr isotopic analyses of the Jianxiashan pluton in the western end of the Eastern Kunlun Range. The pluton is composed of tonalite, granodiorite, and monzogranites. Our new data suggest that the pluton formed during the late Devonian‐early Carboniferous with ages of 339–358 Ma. These rocks have high A/CNK = 1.06–1.30, with 1.11–3.80% of normative corundum and are characterized by negative Eu anomalies and strong depletion in Ba, Nb, and Sr elements. The zircon Hf isotopic analyses give predominantly negative εHf(t) values (−9.25 to −2.80), whereas the values of inherited zircons are various from −25.84 to +8.80. The U–Pb age and Hf isotopic data of these inherited zircons are similar to the widespread meta‐sediments of Kuhai Group basement. The peraluminous granitoids have negative εNd(t) values (−7.1 to −5.1) and relatively high initial 87Sr/86Sr ratios (0.71009). These isotopic compositions suggest that the Kuhai Group could possibly be the source rocks of these peraluminous granitoids. We suggest the tonalite and granodiorite are I‐S transition type, whereas the monzogranite is highly fractionated S‐type formed in a back‐arc extensional tectonic setting, which was possibly related to the northern subduction of the Paleo‐Kunlun oceanic lithosphere. [ABSTRACT FROM AUTHOR]

The rapid development of urbanization and agriculture poses serious impacts on groundwater in arid and semi-arid areas, which typically have high groundwater depletion rates. In this study, chemical and isotopic analyses combined with different data interpretation methods (diagrams, bivariate analyses, principal component analysis (PCA), and hierarchical cluster analysis (HCA)) were used to identify the major factors controlling groundwater chemistry in an arid and semi-arid region of North China. Sixty-four groundwater samples (35 from unconfined aquifer, 29 from confined aquifer) were collected in Baotou City, North China, and 17 chemical variables were detected for each sample. The complex hydrochemical types in unconfined groundwater (e.g., HCO3-Ca·Mg, HCO3·Cl-Na·Mg, SO4-Na·Mg, and Cl·SO4-Na types) may be related to anthropogenic activities, while the main hydrochemical types in confined groundwater are HCO3-Ca·Mg, HCO3-Na·Mg, HCO3·Cl-Na·Ca, SO4·HCO3-Na·Mg, and Cl·SO4-Na types. Three component models for unconfined and confined groundwater were revealed using PCA, which explained approximately 79.69% and 80.68% of the data variance, respectively, providing a deeper insight into groundwater composition controlled by geochemistry and anthropogenic activities. Three clusters were yielded from HCA. The factors and identified clusters were verified with hydrochemical investigations. Among the natural factors, the main hydrochemical processes involve the dissolution of various minerals (halite, gypsum, feldspar, fluorite, mirabilite, biotite, dolomite, and calcite), cation exchange, evaporation, and mixing. The anthropogenic factors include domestic sewage intrusion and agricultural activities, which are most likely to lead to further declines in groundwater quality. These findings may be useful for improving groundwater resource management for sustainable development in arid and semi-arid areas. [ABSTRACT FROM AUTHOR]

Coalfield fires are considered a global crisis that contributes significantly to environmental destruction and loss of coal resources and poses a serious threat to human safety and health. In this paper, research related to the initiation, development, and evolution of coalfield fires is reviewed. The existing detection and control techniques of coalfield fires are also reviewed. Traditional firefighting is associated with waste of resources, potential risks of recrudescence, potential safety hazards, extensive and expensive engineering works, and power shortages. Recently, coalfield fires have been recognized as having significant potential for energy conservation and heat energy recovery. Thermoelectric power generation is regarded as a suitable technology for the utilization of heat from coalfield fires. The extraction of heat from coalfield fires can also control coalfield fires and prevent reignition leading to combustion. Technologies for absorbing heat from burning coal and overlying rocks are also analyzed. In addition, the control mode of "three-region linkage" is proposed to improve firefighting efficiency. Integrating heat energy recovery with firefighting is an innovative method to control coalfield fires. [ABSTRACT FROM AUTHOR]

Inflammation is as an important component of intestinal tumorigenesis. The activation of Toll‐like receptor 4 (TLR4) signalling promotes inflammation in colitis of mice, but the role of TLR4 in intestinal tumorigenesis is not yet clear. About 80%–90% of colorectal tumours contain inactivating mutations in the adenomatous polyposis coli (Apc) tumour suppressor, and intestinal adenoma carcinogenesis in familial adenomatous polyposis (FAP) is also closely related to the germline mutations in Apc. The ApcMin/+ (multiple intestinal neoplasia) model mouse is a well‐utilized model of FAP, an inherited form of intestinal cancer. In this study, ApcMin/+ intestinal adenoma mice were generated on TLR4‐sufficient and TLR4‐deficient backgrounds to investigate the carcinogenic effect of TLR4 in mouse gut by comparing mice survival, peripheral blood cells, bone marrow haematopoietic precursor cells and numbers of polyps in the guts of ApcMin/+ WT and ApcMin/+ TLR4−/− mice. The results revealed that TLR4 had a critical role in promoting spontaneous intestinal tumorigenesis. Significant differential genes were screened out by the high‐throughput RNA‐Seq method. After combining these results with KEGG enrichment data, it was determined that TLR4 might promote intestinal tumorigenesis by activating cytokine‐cytokine receptor interaction and pathways in cancer signalling pathways. After a series of validation experiments for the concerned genes, it was found that IL6, GM‐CSF (CSF2), IL11, CCL3, S100A8 and S100A9 were significantly decreased in gut tumours of ApcMin/+ TLR4−/− mice compared with ApcMin/+ WT mice. In the functional study of core down‐regulation factors, it was found that IL6, GM‐CSF, IL11, CCL3 and S100A8/9 increased the viability of colon cancer cell lines and decreased the apoptosis rate of colon cancer cells with irradiation and chemical treatment. [ABSTRACT FROM AUTHOR]

Based on the mobile monitoring network of tectonic geochemical in the Mid-East section of Qilian mountain, the precursory anomaly analysis and seismic situation tracking in the seismic hazard area were carried out by monitoring the concentration of soil gas radon crossing fault and combining with the distribution characteristics of seismic activity b value. Results show that the concentration of radon released changed significantly difference in the Mid-East segment of Qilian mountain during 2007–2013, under the background of the regional stress field enhancement, the gas release concentration of Gulang fault significantly decline, implying there is an obvious squeezing and the fault stress accumulation resulting in the decrease of porosity and radon concentration, so we circle a potential over magnitude 6 earthquake hazard fault segment in the future. Subsequently the 2016 Menyuan Ms6.4 earthquake occurred in this hazard zone. Therefore, we believe that soil gas radon can be used as a tracer for regional fault tectonic activities and stress changes, and it is necessary to pay attention to the monitoring of cross-fault soil gas in earthquake precursor observation. [ABSTRACT FROM AUTHOR]

Predicted polymorph manipulation offers a cutting-edge route to design function-oriented materials in an exotic double perovskite-related oxide A2BB′O6 with small A-site cations. Herein, first-principles density functional theory calculations in light of the equation of state for solid, for the first time, was used to predict the Mg3TeO6 (R3¯)-to-perovskite (P21/n) type phase transition in Mn3TeO6 at around 5 GPa, regardless of the deployment of magnetic interactions. The high-pressure synthesis and synchrotron diffraction crystal structure analysis corroborated experimentally the polymorph variation in Mn22+Mn2+Te6+O6, which was accompanied by a 13 K increase in the antiferromagnetic ordering temperature (37 K) in the high-pressure perovskite polymorph compared to that of the ambient-pressure R3¯ phase (24 K). The magnetodielectric coupling remains up to 50 K with the maximum being around the magnetic ordering temperature in the perovskite Mn3TeO6. Thus, the predicted polymorph manipulation here offers the possibility of discovering accelerated materials by inverse design in exotic perovskite oxides. [ABSTRACT FROM AUTHOR]