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The installation of pipes in tunnel construction using the external welding method requires the assistance of a pipe pusher and roller support to push the welded pipe into the tunnel. Accurate determination of pipeline push resistance and the selection of an appropriate pipe pusher model are crucial factors for successful construction. Currently, there is no effective method available for predicting push resistance, which may result in inaccurate estimation and inadequate thrust provided by the selected pipe pusher. Therefore, this study aims to establish a reliable formula for calculating push resistance through theoretical analysis and numerical simulation. Additionally, we investigate the rolling resistance coefficient between the pipe and roller wheel to develop a corresponding prediction formula. Finally, a test platform is set up to validate our proposed formula for estimating push resistance. The results demonstrate that there is approximately a 5% error between the calculated values and the test values, confirming that this method effectively predicts pipeline push resistance.

[INLINE:1] The safety and effectiveness of magnetic resonance-guided focused ultrasound thalamotomy has been broadly established and validated for the treatment of essential tremor. In 2018, the first magnetic resonance-guided focused ultrasound system in Chinese mainland was installed at the First Medical Center of the PLA General Hospital. This prospective, single center, open-label, single-arm study was part of a worldwide prospective multicenter clinical trial (ClinicalTrials.gov Identifier: NCT03253991) conducted to confirm the safety and efficacy of magnetic resonance-guided focused ultrasound for treating essential tremor in the local population. From 2019 to 2020, 10 patients with medication refractory essential tremor were recruited into this open-label, single arm study. The treatment efficacy was determined using the Clinical Rating Scale for Tremor. Safety was evaluated according to the incidence and severity of adverse events. All of the subjects underwent a unilateral thalamotomy targeting the ventral intermediate nucleus. At the baseline assessment, the estimated marginal mean of the Clinical Rating Scale for Tremor total score was 58.3 ± 3.6, and this improved after treatment to 23.1 ± 6.4 at a 12-month follow-up assessment. A total of 50 adverse events were recorded, and 2 were defined as serious. The most common intraoperative adverse events were nausea and headache. The most frequent postoperative adverse events were paresthesia and equilibrium disorder. Most of the adverse events were mild and usually disappeared within a few days. Our findings suggest that magnetic resonance-guided focused ultrasound for the treatment of essential tremor is effective, with a good safety profile, for patients in Chinese mainland.

This research aimed to examine shortcomings such as low efficiency and unstable coal release of 2313 large inclined-angle comprehensively released working faces in 230 mining areas of a mine in Shandong. Through the study of the actual working conditions of the large inclined-angle comprehensive release working face, it is concluded that the mining efficiency of the large inclined-angle coal seam is mainly related to the sequence of coal release, the step distance of the coal release, the distance between the end faces, the mining height, the working resistance of the hydraulic bracket and other factors. Taking ZF5600/16.5/26 hydraulic support as an example, simulation software was used to study the influencing factors of coal release efficiency, and the most efficient coal release method was found through the control variable method, so as to improve the mining recovery efficiency of the overall working face of the large inclined-angle coal seam, and after optimizing the working conditions of the hydraulic support, the top coal recovery efficiency was increased by 14.3% compared with the previous one after the actual statistics of the field situation.

Background: MR-guided focused ultrasound (MRgFUS) thalamotomy is a novel and effective treatment for medication-refractory tremor in essential tremor (ET), but how the brain responds to this deliberate lesion is not clear. Objective: The current study aimed to evaluate the immediate and longitudinal alterations of functional networks after MRgFUS thalamotomy. Methods: We retrospectively obtained preoperative and postoperative 30-day, 90-day, and 180-day data of 31 ET patients subjected with MRgFUS thalamotomy from 2018 to 2020. Their archived resting-state functional MRI data were used for functional network comparison as well as graph-theory metrics analysis. Both partial least squares (PLS) regression and linear regression were conducted to associate functional features to tremor symptoms. Results: MRgFUS thalamotomy dramatically abolished tremors, while global functional network only sustained immediate fluctuation within one week after the surgery. Network-based statistics have identified a long-term enhanced corticostriatal subnetwork by comparison between 180-day and preoperative data (P = 0.019). Within this subnetwork, network degree, global efficiency and transitivity were significantly recovered in ET patients right after MRgFUS thalamotomy compared to the pre-operative timepoint (P

BackgroundWe explored the prognostic and immunogenic characteristics of iron pendant disease regulators in colon cancer to provide a scientific basis for the prediction of tumor prognosis-related markers and potential immunotherapeutic drug targets.MethodsRNA sequencing and matched complete clinical information of colon cancer (COAD) were retrieved from the UCSC Xena database, and genomic and transcriptomic data of colon cancer from the TCGA database were downloaded. Then univariate and multifactorial Cox regression were used to process these data. The prognostic factors were analyzed by single-factor and multi-factor Cox regression, followed by Kaplan-Meier survival curves with the aid of R software “survival” package. Then we use FireBrowse online analysis tool to analyze the expression variation of all cancer genes, and draw a histogram according to the influencing factors to predict the 1, 3, and 5 year survival rates of patients.ResultsThe results show that age, tumor stage and iron death score were significantly correlated with prognosis (p

PurposeAdvanced cutaneous squamous cell carcinomas (cSCC) can have unclear borders, and simple expanded resection may not only destroy surrounding normal tissues unnecessarily, but can also leave residual tumor cells behind. In this article, we describe a new method for resection and evaluate its accuracy.MethodsThe magnetic resonance imaging (MRI) data of 12 patients with advanced cSCC were reconstructed to obtain three-dimensional (3D) tumor models and guide plates for surgeries. Thirty-eight patients with the same cSCC stage, who underwent expanded resection, were included. The distances between the upper, lower, left and right horizontal margins and tumor pathological boundaries were classified as “positive”, “close” (0–6 mm), “adequate” (6–12 mm) or “excessive” (>12 mm). The positive margin rate and margin distance were compared between the groups.ResultsThe 3D tumor models of 12 patients were all successfully reconstructed. The positive rate of 48 surgical margins in the guide plate group was 2.1%, and the proportion of “adequate” margins was 70.8%. A total of 152 margins of 38 patients were included in the extended resection group, for which the positive rate was 13.8%; this was higher than that of the guide plate group (P = 0.045). The proportion of “adequate” margins was 27.6%, with group differences seen in the distance distribution (P

After the outbreak of COVID-19, medical institutions in China and even around the world are facing unprecedented challenges. In order to minimize the adverse impact of this unexpected epidemic on patients who need radiotherapy, the expert group of our radiotherapy center immediately formulated comprehensive emergency plans and prevention and control measures, partitioned the work area, launched online staff training, and optimized the radiotherapy process after the outbreak, which provided a strong guarantee for the safe and orderly operation of our radiotherapy center and kept the infection rate to an extremely low level. We hope our experience could provide reference and suggestions for other medical institutions.

Abstract Background The development of tumor cells inside the lymphatics or blood vessels is known as lymphovascular invasion (LVI). The correlation between LVI, lymph node metastasis (LNM), and the diagnosis of superficial esophageal carcinoma (SEC) remains unclear. Methods We searched Embase, PubMed, Web of Science, and Cochrane Library databases for prospective articles to better understand the relationship between LVI, LNM, and SEC diagnosis. Results We included 23 articles containing data for 4749 patients (range: 54–598) in our meta-analysis. The hazard ratio between LVI and overall survival (OS) was 1.85 with 95% confidence interval (CI) (1.10–3.11, P = 0.02). LNM rate was higher in SEC patients with LVI than SEC patients without LVI (univariate: OR = 4.94, 95% CI: 3.74–6.53, P

Large-scale inverted siphon is a key hydraulic structure for building a national water network and realizing the spatial balance of water resources, and its safety under the action of earthquakes has become the focus of trans-basin water transfer projects. In this paper, Xiazhuang inverted siphon of water diversion in Central Yunnan is taken as the research object. Viscoelastic artificial boundary was used to simulate seismic waves spread in the soil, which include the natural site seismic waves and the waves fitted manually according to the site conditions. A three-dimensional finite element model of soil-structure-fluid interaction was established by software of ABAQUS, in which the fluid-structure interaction was simulated by user-defined element (UEL) built on additional Mass Method. Seismic response and damage analysis of large inverted siphon structure are carried out by the model. The results show that the dynamic displacement of the inverted siphon pipe is mainly horizontal sloshing, and the dynamic response of the pipe increases due to the water in the pipe; even the dynamic stress value in some areas is close to the design value of the concrete tensile strength. The damage analysis of inverted siphon pipe shows that the plastic deformation and the damage area develop rapidly with the increase of the peak ground acceleration (PGA), and the tensile damage area is generally larger than the compression damage area. The damage factor of the pipe under the working condition of the water is obviously larger relative to the working condition of no water. Therefore, it is suggested that the damage effect of earthquake should be considered in the design of large inverted siphon in high-intensity area.

MRgFUS has just been made available for the 1.7 million Parkinson's disease patients in China. Despite its non-invasive and rapid therapeutic advantages for involuntary tremor, some concerns have emerged about outcomes variability, non-specificity, and side-effects, as little is known about its impact on the long-term plasticity of brain structure. We sought to dissect the characteristics of long-term changes in brain structure caused by MRgFUS lesion and explored potential biological mechanisms. One-year multimodal imaging follow-ups were conducted for nine tremor-dominant Parkinson's disease patients undergoing unilateral MRgFUS thalamotomy. A structural connectivity map was generated for each patient to analyze dynamic changes in brain structure. The human brain transcriptome was extracted and spatially registered for connectivity vulnerability. Genetic functional enrichment analysis was performed and further clarified using in vivo emission computed tomography data. MRgFUS not only abolished tremors but also significantly disrupted the brain network topology. Network-based statistics identified a U-shape MRgFUS-sensitive subnetwork reflective of hand tremor recovery and surgical process, accompanied by relevant cerebral blood flow and gray matter alteration. Using human brain gene expression data, we observed that dopaminergic signatures were responsible for the preferential vulnerability associated with these architectural alterations. Additional PET/SPECT data not only validated these gene signatures, but also suggested that structural alteration was significantly correlated with D1 and D2 receptors, DAT, and F-DOPA measures. There was a long-term dynamic loop between structural alteration and dopaminergic signature for MRgFUS thalamotomy, which may be closely related to the long-term improvements in clinical tremor.

The regional differences in the Yellow River Basin have increased, and the aggravation of this unbalanced state has seriously restricted the high-quality development of the Yellow River Basin during the accelerated urbanisation that has taken place in recent years. In this regard, heterogeneity in the trends of evolution and the causes of population shrinkage in different regions of the Yellow River Basin can be adopted as targeted countermeasures. The present study uses data from the fifth, sixth, and seventh national censuses and takes the administrative units of different levels in the Yellow River Basin as the object, considering 72 prefecture-level cities within the autonomous prefectures and 595 county-level administrative units in nine provinces (autonomous regions). The population shrinkage coefficient, night light index, bivariate spatial autocorrelation, geographic detectors, and other methods were used, with the final objective of exploring the spatial–temporal distribution pattern and impact mechanism of urban shrinkage from 2000 to 2020. The results of the study show the following: (1) The shrinkage patterns in 2000–2010 (T1) and 2010–2020 (T2) were quite different. From T1 to T2, the shrinkage situation worsened, with the number of districts experiencing population shrinkage increasing from 175 to 373 and the number of districts experiencing continuous night light and shrinkage districts increasing from 146 to 163. (2) The phenomenon of urban shrinkage is spatially scale dependent, with the shrinkage of prefecture-level cities and county-level cities being characterised by both spatial differentiation and spatial nesting relationships. (3) There is a certain inconsistency in the representation of the shrinkage patterns of the nighttime lighting and population data. The nighttime lighting dimension can reflect the structural shrinkage characteristics of the city more accurately and sensitively, and the representation of population loss is lagging. (4) The main impact factors and the intensity of urban shrinkage are the aggravated aging level, the declining level of industrial greening and intensification under market-driven economic structure adjustments, and the decreased natural growth rate in the population structure and public service facilities.

Background and purpose Individuals with intracranial artery occlusion have high rates of ischaemic events and recurrence. It has been challenging to identify patients who had high-risk stroke using a simple, valid and non-invasive screening approach. This study aimed to investigate whether fluid-attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH), a specific imaging sign on the FLAIR sequence, could be a predictor of ischaemic events in a population with internal carotid artery (ICA) or middle cerebral artery (MCA) occlusion.Methods We retrospectively analysed 147 patients (mean 60.43±12.83 years) with 149 lesions, including 37 asymptomatic and 112 symptomatic cases of ICA or MCA occlusion. Symptomatic occlusion was considered if ischaemic events were present in the relevant territory within 90 days. FVH Alberta Stroke Program Early Computed Tomography Score (FVH-ASPECTS: 0–7, with 0 indicating absence of FVH and 7 suggesting prominent FVH) and collateral circulation grade were assessed for each participant. Multivariable logistic regression analysis was performed to detect independent markers associated with symptomatic status.Results A lower FVH-ASPECTS was associated with a more favourable collateral circulation grade (rho=−0.464, p