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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]

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]

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]

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]

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]

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]

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]

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]

Key message: We identified three dormant stages of Polygonatum kingianum and changes that occurred during dormancy transition in the following aspects including cell wall and hormones, as well as interaction among them.Abstract: Polygonatum kingianum Coll.et Hemsl (P. kingianum) is an important traditional Chinese medicine, but the mechanism of its rhizome bud dormancy has not yet been studied systematically. In this study, three dormancy phases were induced under controlled conditions, and changes occurring during the transition were examined, focusing on phytohormones and the cell wall. As revealed by HPLC-MS (High Performance Liquid Chromatography-Mass Spectrometry) analysis, the endo- to non-dormancy transition was association with a reduced abscisic acid (ABA)/gibberellin (GA3) ratio, a decreased level of auxin (IAA) and an increased level of trans-zeatin (tZR). Transmission electron microscopy showed that plasmodesmata (PDs) and the cell wall of the bud underwent significant changes between endo- and eco-dormancy. A total of 95,462 differentially expressed genes (DEGs) were identified based on transcriptomics, and clustering and principal component analysis confirmed the different physiological statuses of the three types of bud samples. Changes in the abundance of transcripts associated with IAA, cytokinins (CTKs), GA, ABA, brassinolide (BR), jasmonic acid (JA), ethylene, salicylic acid (SA), PDs and cell wall-loosening factors were analysed during the bud dormancy transition in P. kingianum. Furthermore, nitrilase 4 (NIT4) and tryptophan synthase alpha chain (TSA1), which are related to IAA synthesis, were identified as hub genes of the co-expression network, and strong interactions between hormones and cell wall-related factors were observed. This research will provide a good model for chilling-treated rhizome bud dormancy in P. kingianum and cultivation of this plant. [ABSTRACT FROM AUTHOR]

Unfertilized ovary culture constitutes an effective method for haploid breeding and can greatly shorten the breeding time. This method has been successfully used for breeding in many species, but reports of this method for breeding watermelon are scarce. Therefore, we performed an experiment to induce haploid plantlets. We evaluated the effects of several important factors on unfertilized ovary cultures of watermelon, including genotype, medium, the duration of induction and the development stage of the ovaries. The results revealed that the genotype of donor plants was a key factor for in vitro gynogenesis. The induction rate of eight watermelon cultivars varied from 0.00 to 15.14 ELSs per100 ovary slices. The most effective induction medium and maturation medium were MS medium supplemented with 3 mg L− 1 2,4-D, 2 mg L− 1 BAP, 0.5 mg L−1 NAA and MS supplemented with 0.8 mg L− 1 BAP and 0.2 mg L− 1 NAA, respectively. The duration of induction significantly influenced ELS formation. The optimum duration was 13 days, and unfertilized ovaries collected at anthesis had the higher induction rate. We obtained more than 100 plantlets and used chromosome counting and flow cytometry to determine the ploidy levels of 50 of them, among which 48 were haploid and 2 were diploid. Our results demonstrated that in vitro gynogenesis can be induced in watermelon by unfertilized ovaries culture. [ABSTRACT FROM AUTHOR]

Background: Interleukin-1 alpha (IL-1α) plays an important role in tumorigenesis and angiogenesis of gastric cancer. The interleukin-1 receptor antagonist (IL-1RA) inhibits IL-1 selectively and specifically through IL-1R type I (IL-1RI). However, the underlying mechanism by which IL-1RA modulates the interactions of tumor cells and their micro-environment is poorly understood. We have evaluated the role of IL-1RA in the metastatic process as well as the mutual or reciprocal actions between gastric cancer cells and stromal cells.Materials and methods: The expressions of IL-1α, vascular endothelial growth factor (VEGF), and IL-1RI mRNA were determined by reverse transcriptase-PCR. The regulatory effect of IL-1RA on the secretion of VEGF in human gastric cancer cells and human umbilical vein endothelial cells (HUVECs) was detected by enzyme-linked immunosorbent assay. The effect of IL-1RA on metastatic potential was evaluated using proliferation, invasion, and angiogenesis assays, respectively, including in vitro co-culture system models consisting of tumor cells and stromal cells that were used to detect invasion and angiogenesis.Results: Interleukin-1α mRNA was detected in the higher liver metastatic gastric cell line MKN45. IL-1α protein was expressed in MKN45 cells and in HUVECs. VEGF mRNA and protein were detected in the three gastric cancer cell lines (MKN4, NUGC-4, and AGS). Levels of VEGF secreted by gastric cancer cells and HUVECs appeared to be reduced through the action of IL-1RA via IL-1RI in a dose-dependent manner (P < 0.01). IL-1RA significantly inhibited the proliferation and migration of HUVECs (P < 0.01) and tube formation by HUVECs (P < 0.01), both in a dose-dependent manner. Compared with HUVECs grown without cancer cells (control) or with NUGC-4 cells, tube formation by HUVECs was significantly enhanced by co-culture with MKN45 cells (P < 0.01). The enhanced tube formation in the presence of MKN45 cells was inhibited by the addition of IL-1RA (P < 0.01).Conclusions: The IL-1RA downregulated the metastatic potential of gastric cancer through blockage of the IL-1α/VEGF signaling pathways. IL-1RA has the potential to play a role in the treatment of gastric cancer. [ABSTRACT FROM AUTHOR]

To measure the latency between human motion stimulation and stereo image display response in a visual feedback-based minimally invasive surgical (MIS) robotic system, a method was proposed by comparing the orientations of input and output events through image-processing technology. This method used a black bar to keep pace with the measured joint rotating at a number of speeds. During tests, an external camera was placed in front of the apparatus with a proper visual field, so that it can simultaneously view orientations of both bars fixed on the corresponding joints. After quantitatively analyzing the accuracy of the proposed measurement method, the method was applied to a visual feedback-based master-slave robotic system with two-degrees-of-freedom. Experimental results show that the latency of the overall system was approximately 250 ms, and the opposite clearance of the measured joint was in the range of 1.7°-1.9°. [ABSTRACT FROM AUTHOR]

Groundwater is a vital source for domestic and irrigation purposes in the loess area of Northwest China where climate is arid. However, the quality of groundwater in this area is deteriorating due to intensive industrial and agricultural activities, and this has a great adverse impact on human health. In order to better understand the pollution status of groundwater and the health risks to local residents, comprehensive water quality index was applied to assess the quality of drinking water in Yulin City, Northwest China, and sodium adsorption ratio, sodium percentage, residual sodium carbonate and permeability index were used to evaluate the quality of irrigation water. Moreover, the health risks caused by ingestion of groundwater were evaluated using the model proposed by the Ministry of Environmental Protection of the PR China. The results show that all groundwater samples for irrigation will not induce soil salinization, but more than half of them are not suitable for drinking, and Fe, Mn, TH, Mg and NO-N are the common contaminants which are mainly from natural processes, industrial and agricultural activities. The health risk assessment indicates that children face greater non-carcinogenic risk than adults. The order of contribution of contaminants to non-carcinogenic risk is NO > As > F > Fe > Mn > Ba > Cr > Zn > NO . The average carcinogenic risk of carcinogens (Cr and As) is 1.17 × 10 and 1.37 × 10 for adults and children, respectively, which surpasses the permissible level (1 × 10) stipulated by the Ministry of Environmental Protection of the PR China. Hence, effective measures are highly demanded to manage groundwater pollution and reduce the risks to human health. [ABSTRACT FROM AUTHOR]

The exothermic efficiency of microwave heating an electrolyte/water solution is remarkably high due to the dielectric heating by orientation polarization of water and resistance heating by the Joule process occurred simultaneously compared with pure water. A three-dimensional finite element numerical model of multi-feed microwave heating industrial liquids continuously flowing in a meter-scale circular tube is presented. The temperature field inside the applicator tube in the cavity is solved by COMSOL Multiphysics and professional programming to describe the momentum, energy and Maxwell's equations. The evaluations of the electromagnetic field, the temperature distribution and the velocity field are simulated for the fluids dynamically heated by single- and multi-feed microwave system, respectively. Both the pilot experimental investigations and numerical results of microwave with single-feed heating for fluids with different effective permittivity and flow rates show that the presented numerical modeling makes it possible to analyze dynamic process of multi-feed microwave heating the industrial liquid. The study aids in enhancing the understanding and optimizing of dynamic process in the use of multi-feed microwave heating industrial continuous flow for a variety of material properties and technical parameters. [ABSTRACT FROM AUTHOR]

The heat flow in crust and the thermal sdtress generated by the flow play a very important role in earthquake occurrence. Different crustal structure has different effect on heat distribution and associated thermal stress. In all of typical seismogenic crustal structure models, including the bulge of Moho surface, the deep-large fault in the mid-lower crust, low-velocity and high-conductive layer in the middle crust, and the typical crustal structure in mid-upper crust, the thermal stress produced by deep heat disturbance may move up to the mid-upper crust. This leads to upper brittle part of crust break and hence, strong earthquakes. This result is constructive in enhancing our understanding of the role of deep heat flow in curst in development of earthquake and its generation, as well as the generation mechanism of the shallow flowing fluid. [ABSTRACT FROM AUTHOR]

TRAIL preferentially induces apoptosis in tumor cells and virus-infected cells. Unlike other tumor necrosis factor family members, TRAIL does not kill cells from most normal tissues and has thus been proposed as a promising new cancer treatment. Our study demonstrated that IFN? combined with TRAIL can trigger apoptosis in vitro in several resistant thyroid tumor cell lines, such as thyroid anaplastic carcinoma cells (ARO cells), while either agent alone exerts only a minimal effect. We further tested this effect on a mouse thyroid tumor model, when in vivo tumor growth was also significantly inhibited by this combination. The mechanism of how IFN? sensitized thyroid carcinoma cells to TRAIL-induced apoptosis was investigated by screening global gene alterations in ARO cells treated with IFN?. Microarray data revealed that a proapoptotic gene, Bak, is markedly upregulated by IFN?, and this was confirmed by RNase protection assay. Western blot analysis also showed a significant increase in Bak at the protein level. Upregulation of Bak and sensitization for apoptosis by IFN? was blocked by overexpression of antisense Bak in ARO cells. Furthermore, overexpression of Bak sensitized ARO cell to TRAIL-induced apoptosis without the need for IFN? pretreatment. This suggests that Bak is a regulatory molecule involved in IFN?-facilitated TRAIL-mediated apoptosis in thyroid cancer cells.Oncogene (2004) 23, 928-935. doi:10.1038/sj.onc.1207213 Published online 1 December 2003 [ABSTRACT FROM AUTHOR]

Venom gland is a highly efficient venom production system to maintain their predatory arsenal. Venom toxins mRNA has been shown to increase abruptly in snake after venom expenditure, while the dynamics of venom accumulation during synthesis are poorly understood. Here, PacBio long-read sequencing, Illumina RNA sequencing (RNA-seq), and label-free proteome quantification were used to investigate the composition landscape and time- and temperature-dependent dynamics changes of the Bungarus multicinctus venom gland system. Transcriptome data (19.5223 Gb) from six adult B. multicinctus tissues were sequenced using PacBio RS II to generate a reference assembly, and average 7.28 Gb of clean RNA-seq data was obtained from venom glands by Illumina sequencing. Differentially expressed genes (DEGs) mainly were protein processing rather than venom toxins. Post-translational modifications provided the evidence of the significantly different proportions of toxins in the venom proteome with the changing of replenishment time and temperature, but constant of venom toxins mRNA in the venom gland transcriptome. Dynamic of toxins and genes involved in venom gland contraction suggesting the formation of the mature venom gland system would take at least 9 days. In addition, 59 toxin processing genes were identified, peptidylprolyl isomerase B of which underwent positive selection in Toxicofera. These results provide a reference for determining the extraction time of venom, production of polyclonal and monoclonal antibody for precise treatment plans of venomous snakebites, and construction of an in vitro synthesis system for snake venom protein. [ABSTRACT FROM AUTHOR]