Different percutaneous transhepatic biliary stent placements and catheter drainage in the treatment of middle and low malignant biliary obstruction

BACKGROUND For cases of middle and low biliary obstruction with left and right hepatic duct dilatation,the type of approach and whether different approaches affect the difficulty of puncture operation and intraoperative and postoperative complications have not been discussed in detail.AIM To compare the efficacy of different percutaneous transhepatic biliary stent placements and catheter drainage in treating middle and low biliary obstruction.METHODS A retrospective analysis was performed on the medical records of 424 patients with middle and low biliary obstruction who underwent percutaneous liver puncture biliary stent placement and catheter drainage at the Department of Interventional Radiology,Shaanxi Provincial People’s Hospital between March 2016 and March 2022.Based on the puncture path,patients were categorized into two groups:Subxiphoid left hepatic lobe approach group(Group A,224 cases)and right intercostal,right hepatic lobe approach group(Group B,200 cases).Liver function improvement,postoperative biliary bleeding incidence,postoperative pain duration,and abdominal effusion leakage around the drainage tube were compared between the two groups at 3 d and 1 wk after the surgery.Patient survival time was recorded during follow-up.RESULTS All 424 surgeries were successful without adverse events.Group A comprised 224 cases,and Group B had 200 cases.There was no statistically significant difference in basic data between Group A and Group B(P>0.05).No significant difference in postoperative biliary bleeding incidence was observed between the groups(P>0.05).The decreased rates for total bilirubin(Group A:69.23±4.50,Group B:63.79±5.65),direct bilirubin(Group A:79.30±11.19,Group B:63.62±5.64),and alkaline phosphatase(Group A:60.51±12.23,Group B:42.68±23.56)in the 1st wk after surgery were significantly faster in Group A than in Group B.The decreased rate of gamma-glutamyl transpeptidase was also significantly faster in Group A at both 3 d(Group A:40.56±10.32,Group B:32.22±5.12)and 1 wk(Group A:73.19±7.05,Group B:58.81±18.98)after surgery(P<0.05).Group A experienced significantly less peritoneal effusion leakage around the drainage tube than Group B(P<0.05).The patient survival rate was higher in Group A compared to Group B(P<0.05).CONCLUSION In treating jaundice patients with middle and low biliary obstruction,a percutaneous left liver puncture demonstrated better clinical efficacy than a percutaneous right liver puncture.

Erratum to“A note on overshoot estimation in pole placements”

There is a mild flaw in the statement of Proposition 2.1 in the above paper （cf. [1] ）. We restate it as follows.

A Comparative Study of the Short-Term Efficacy of Laparoscopic Radical Resection of Right-Sided Colon Cancer with Two Different Surgeon Positions and Trocar Placements

Objective: To investigate the short-term efficacy of laparoscopic radical resection of right-sided colon cancer with two different surgeon positions and trocar placements. Methods: The data of 78 patients who underwent laparoscopic radical resection of right-sided colon cancer between January 2018 and August 2019 were retrospectively analysed. The surgical method was selected by the patients. The patients were divided into two groups according to the surgeons’ positioning habits and trocar placements. The group with the lead surgeon standing between the patient’s legs had 35 patients, and the group with the lead surgeon standing at the left side of the patient had 43 patients. The operation time, intraoperative blood loss, postoperative anal gas evacuation time, postoperative urinary catheter indwelling time, postoperative hospital stay, C-reactive protein (CRP) level on the first day after surgery, and postoperative pathological data and complications were compared between the two groups. Results: All patients underwent the laparoscopic radical resection of right-sided colon cancer, none converting to laparotomy. No significant difference (P > 0.05) in intraoperative blood loss (57.6 ± 21.3 ml vs 60.2 ± 35.3 ml), postoperative anal gas evacuation time (3.5 ± 1.1 d vs 3.8 ± 1.3 d), postoperative urinary catheter indwelling time (2.6 ± 1.3 d vs 2.4 ± 1.2 d), postoperative hospital stay (7.1 ± 1.8 d vs 7.5 ± 2.1 d), or CRP level on the first day after surgery (54.7 ± 9.6 mg/L vs 53.9 ± 8.2 mg/L) was detected between the two groups. The operation time was shorter in the group with the lead surgeon standing between the patient’s legs (185.2 ± 25.6 min vs 196.2 ±19.7 min) (P < 0.05). The two groups did not differ significantly in the tumour length (4.2 ± 1.3 cm vs 3.9 ± 1.5 cm), number of dissected lymph nodes (27.5 ± 11.6 vs 25.1 ± 15.4), pathological type, or postoperative pathological tumour-node-metastasis stage (P > 0.05). No patients died or had anastomotic fistula during their postoperative hospital stay, and the incidence of postoperative complications did not differ between the two groups (22.9% (8/35) vs 23.3% (10/42);P > 0.05). Conclusion: Under the principle of radical resection, the surgeon should adopt the most suitable standing position and trocar placement according to the specific situation. If the surgeon stands between the patient’s legs, this might shorten the operation time and promote a smoother surgery.

Nursing students’experiences of horizontal violence and occupational belonging during clinical placements

Background:Horizontal violence has negatively affected the students’active learning,interpersonal relationship,and occupational belonging.However,little attention has been paid to the relationship between horizontal violence and occupational belonging among nursing students.Objective:The objective of this study was to explore the frequency,types,perpetrators,effects,and responses of horizontal violence experienced by nursing students and the relationship between occupational belonging and horizontal violence.Materials and Methods:The present study used a descriptive,cross-sectional survey design.The data were collected from the 277 undergraduate nursing students selected by convenience sampling method using personal characteristics form,horizontal violence survey,and occupational belonging subscale at nursing faculty in Istanbul.Results:The first three horizontal violence behaviors experienced by nursing students were found,respectively:being forced to do trivial and unimportant work which are not the students’responsibility(84.1%),being exposed to sarcastic remarks by nurses(80.9%)and unwillingness of the nurse to help and lack of support(80.9%)and being ignored by nurses(77.3%).Nearly half of the students(48.4%)considered leaving nursing profession as a result of horizontal violence.There was a negative relation between horizontal violence and occupational belonging(P<0.05).As horizontal violence scores increased,occupational belonging scores decreased.Conclusions:Findings from this study shown that horizontal violence decreasing occupational belonging,and so nursing students consider leaving nursing profession or education.Further studies are needed to better demonstrate addressing the horizontal violence bilaterally and the effective preventive interventions.

Study of the Discount on Private Placements and Risk of Stock Market Crash in Listed Companies

With the gradual completion of the split-share structure reform,private placement has gradually become the mainstream of refinancing. One of the points that the practical and theoretical circles are widely concerned about is that the private placement price is often higher than the market price at the time of the private placement. High discounts are often accompanied by the transmission of benefits,and the increase in insider information will lead to the risk of a stock market crash? This paper intends to use the data of A-share listed companies from 2006 to 2015 to empirically study the relationship between the discount on private placements and the risk of stock market crash. At the same time,this paper examines whether the degree of information asymmetry plays a regulatory role in the relationship between the discount on private placements and the risk of stock market crash. This paper provides a certain reference for the regulatory authorities to improve the relevant laws and regulations in the private placement,and to provide a certain reference for the protection of the interests of small and medium-sized investors.

Algorithms for the Optimization of Well Placements—A Comparative Study

The Artificial Bee Colony (ABC) is one of the numerous stochastic algorithms for optimization that has been written for solving constrained and unconstrained optimization problems. This novel optimization algorithm is very efficient and as promising as it is;it can be favourably compared to other optimization algorithms and in some cases, it has been proven to be better than some known algorithms (like Particle Swarm Optimization (PSO)), especially when used in Well placement optimization problems that can be encountered in the Petroleum industry. In this paper, the ABC algorithm has been modified to improve its speed and convergence in finding the optimum solution to a well placement optimization problem. The effects of variations of the control parameters for both algorithms were studied, as well as the algorithms’ performances in the cases studied. The modified ABC (MABC) algorithm gave better results than the Artificial Bee Colony algorithm. It was noticed that the performance of the ABC algorithm increased with increase in the number of its optimization agents for both algorithms studied. The modified ABC algorithm overcame the challenge posed by the use of uniformly generated random numbers with very rough NPV surface. This new modified ABC algorithm proposed in this work will be a great tool in optimization for the Petroleum industry as it involves Well placements for optimum oil production.

Hybrid Approach for Cost Efficient Application Placement in Fog-Cloud Computing Environments

Fog computing has recently developed as a new paradigm with the aim of addressing time-sensitive applications better than with cloud computing by placing and processing tasks in close proximity to the data sources.However,the majority of the fog nodes in this environment are geographically scattered with resources that are limited in terms of capabilities compared to cloud nodes,thus making the application placement problem more complex than that in cloud computing.An approach for cost-efficient application placement in fog-cloud computing environments that combines the benefits of both fog and cloud computing to optimize the placement of applications and services while minimizing costs.This approach is particularly relevant in scenarios where latency,resource constraints,and cost considerations are crucial factors for the deployment of applications.In this study,we propose a hybrid approach that combines a genetic algorithm(GA)with the Flamingo Search Algorithm(FSA)to place application modules while minimizing cost.We consider four cost-types for application deployment:Computation,communication,energy consumption,and violations.The proposed hybrid approach is called GA-FSA and is designed to place the application modules considering the deadline of the application and deploy them appropriately to fog or cloud nodes to curtail the overall cost of the system.An extensive simulation is conducted to assess the performance of the proposed approach compared to other state-of-the-art approaches.The results demonstrate that GA-FSA approach is superior to the other approaches with respect to task guarantee ratio(TGR)and total cost.

Layered Coded Cache Placement and Cooperative Delivery with Sharing Links in Satellite-Terrestrial Integrated Networks

Cooperative utilization of multidimensional resources including cache, power and spectrum in satellite-terrestrial integrated networks(STINs) can provide a feasible approach for massive streaming media content delivery over the seamless global coverage area. However, the on-board supportable resources of a single satellite are extremely limited and lack of interaction with others. In this paper, we design a network model with two-layered cache deployment, i.e., satellite layer and ground base station layer, and two types of sharing links, i.e., terrestrial-satellite sharing(TSS) links and inter-satellite sharing(ISS) links, to enhance the capability of cooperative delivery over STINs. Thus, we use rateless codes for the content divided-packet transmission, and derive the total energy efficiency(EE) in the whole transmission procedure, which is defined as the ratio of traffic offloading and energy consumption. We formulate two optimization problems about maximizing EE in different sharing scenarios(only TSS and TSS-ISS),and propose two optimized algorithms to obtain the optimal content placement matrixes, respectively.Simulation results demonstrate that, enabling sharing links with optimized cache placement have more than 2 times improvement of EE performance than other traditional placement schemes. Particularly, TSS-ISS schemes have the higher EE performance than only TSS schemes under the conditions of enough number of satellites and smaller inter-satellite distances.

Characteristics of proppant transport and placement within rough hydraulic fractures

A three-dimensional reconstruction of rough fracture surfaces of hydraulically fractured rock outcrops is carried out by casting process,a large-scale experimental setup for visualizing rough fractures is built to perform proppant transport experiments.The typical characteristics of proppant transport and placement in rough fractures and its intrinsic mechanisms are investigated,and the influences of fracture inclination,fracture width and fracturing fluid viscosity on proppant transport and placement in rough fractures are analyzed.The results show that the rough fractures cause variations in the shape of the flow channel and the fluid flow pattern,resulting in the bridging buildup during proppant transport to form unfilled zone,the emergence of multiple complex flow patterns such as channeling,reverse flow and bypassing of sand-carrying fluid,and the influence on the stability of the sand dune.The proppant has a higher placement rate in inclined rough fractures,with a maximum increase of 22.16 percentage points in the experiments compared to vertical fractures,but exhibits poor stability of the sand dune.Reduced fracture width aggravates the bridging of proppant and induces higher pumping pressure.Increasing the viscosity of the fracturing fluid can weaken the proppant bridging phenomenon caused by the rough fractures.

Efficient Digital Twin Placement for Blockchain-Empowered Wireless Computing Power Network

As an open network architecture,Wireless Computing PowerNetworks(WCPN)pose newchallenges for achieving efficient and secure resource management in networks,because of issues such as insecure communication channels and untrusted device terminals.Blockchain,as a shared,immutable distributed ledger,provides a secure resource management solution for WCPN.However,integrating blockchain into WCPN faces challenges like device heterogeneity,monitoring communication states,and dynamic network nature.Whereas Digital Twins(DT)can accurately maintain digital models of physical entities through real-time data updates and self-learning,enabling continuous optimization of WCPN,improving synchronization performance,ensuring real-time accuracy,and supporting smooth operation of WCPN services.In this paper,we propose a DT for blockchain-empowered WCPN architecture that guarantees real-time data transmission between physical entities and digital models.We adopt an enumeration-based optimal placement algorithm(EOPA)and an improved simulated annealing-based near-optimal placement algorithm(ISAPA)to achieve minimum average DT synchronization latency under the constraint of DT error.Numerical results show that the proposed solution in this paper outperforms benchmarks in terms of average synchronization latency.

Service Function Chain Migration in LEO Satellite Networks

With the advancements of software defined network(SDN)and network function virtualization(NFV),service function chain(SFC)placement becomes a crucial enabler for flexible resource scheduling in low earth orbit(LEO)satellite networks.While due to the scarcity of bandwidth resources and dynamic topology of LEO satellites,the static SFC placement schemes may cause performance degradation,resource waste and even service failure.In this paper,we consider migration and establish an online migration model,especially considering the dynamic topology.Given the scarcity of bandwidth resources,the model aims to maximize the total number of accepted SFCs while incurring as little bandwidth cost of SFC transmission and migration as possible.Due to its NP-hardness,we propose a heuristic minimized dynamic SFC migration(MDSM)algorithm that only triggers the migration procedure when new SFCs are rejected.Simulation results demonstrate that MDSM achieves a performance close to the upper bound with lower complexity.

Energy-efficient joint UAV secure communication and 3D trajectory optimization assisted by reconfigurable intelligent surfaces in the presence of eavesdroppers

We consider a scenario where an unmanned aerial vehicle(UAV),a typical unmanned aerial system(UAS),transmits confidential data to a moving ground target in the presence of multiple eavesdroppers.Multiple friendly reconfigurable intelligent surfaces(RISs) help to secure the UAV-target communication and improve the energy efficiency of the UAV.We formulate an optimization problem to minimize the energy consumption of the UAV,subject to the mobility constraint of the UAV and that the achievable secrecy rate at the target is over a given threshold.We present an online planning method following the framework of model predictive control(MPC) to jointly optimize the motion of the UAV and the configurations of the RISs.The effectiveness of the proposed method is validated via computer simulations.

Endoscopic treatment of extreme esophageal stenosis complicated with esophagotracheal fistula: A case report

BACKGROUND At present,there is no unified and effective treatment for extreme corrosive esophageal stenosis(CES)with esophagotracheal fistula(ETF).This case had extreme and severe esophageal stenosis(ES)and ETF after ingesting an enzyme-based chemical detergent,resulting in a serious pulmonary infection and severe malnutrition.Upper gastrointestinal imaging showed that he had an ETF,and endoscopy showed that he had extreme and severe esophageal stricture.This case was complex and difficult to treat.According to the domestic and foreign lite-rature,there is no universal treatment that is low-risk.CASE SUMMARY A patient came to our hospital with extreme ES,an ETF,and severe malnutrition complicated with pulmonary tuberculosis 1 mo after the consumption of an enzy-me-based detergent.The ES was serious,and the endoscope was unable to pass through the esophagus.We treated him by endoscopic incision method(EIM),esophageal stent placement(ESP),and endoscopic balloon dilation(EBD)by using the bronchoscope and gastroscope.This treatment not only closed the ETF,but also expanded the esophagus,with minimal trauma,greatly reducing the pain of the patient.According to the literature,there are no similar reported cases.CONCLUSION We report,for the first time,a patient with extreme CES complicated with ETF,where the endoscope could not be passed through his esophagus but he could be examined by bronchoscopy and treated by EIM,ESP,and EBD.

Analysis of the Application Effect of Tracheal Stent Placement in the Nutritional Support Treatment of Tracheoesophageal Fistula

Objective:To evaluate and analyze the application effect of tracheal stent placement in nutritional support therapy for tracheoesophageal fistula.Methods:Clinical data of 32 patients who underwent nutritional support therapy for tracheoesophageal fistula in our hospital from September 2021 to September 2022 were collected,and all patients underwent tracheal silicone stenting,comparing dyspnea classification and Karnofsky score before and after stenting,and conducting post-treatment follow-up.Results:In 32 patients with tracheoesophageal fistula,dyspnea grading improved from grades III and IV to grades 0 to II.Before treatment,10 patients(31.06%)were in grade IV,17 patients(53.12%)were in grade III,and five patients(15.62)were in grade II;after treatment,13 patients(40.63%)were in grade I,12 patients(37.50%)were in grade I,and seven patients(21.87%)were in grade 0(P<0.05);Karnofsky score(37.52±4.86 before treatment)improved significantly to 71.39±8.24 one week after treatment(P<0.05).Nine patients with tracheoesophageal fistula were placed with silicone Y14-10-10 stent,11 with silicone 18-14-14 stent,three with silicone Y15-12-12,and seven with silicone stent 16-13-13.Conclusion:Silicone tracheobronchial stent placement for the treatment of tracheoesophageal fistula is technically feasible,simple,and safe,with reliable near-term efficacy,and is worthy of popularization and application.

Clinical Study on Improving Articulation Clarity in Spastic Cerebral Palsy with 120 Cases of Oral-Facial Acupressure Combined with Oral Placement Therapy

Objective:To observe the efficacy of oral-facial acupressure combined with oral placement therapy(OPT)in improving articulation clarity in 120 children with spastic cerebral palsy,and to explore effective therapeutic solutions for speech disorders associated with spastic cerebral palsy.Methods:A total of 120 children with spastic cerebral palsy and speech disorders,meeting the inclusion criteria,were randomly assigned into two groups:60 cases in the treatment group and 60 cases in the control group.The treatment group received orofacial acupressure combined with OPT,while the control group received only OPT.The Oral Motor Function Assessment Scale(OMFAS),developed by the China Rehabilitation Research Centre(CRRC),was used to evaluate the treatment outcomes before and after the intervention.Results:After the treatment,both the treatment and control groups showed improved mobility of the mandible,lips,and tongue.However,the treatment group exhibited significantly better improvement than the control group,with the difference between the two groups being statistically significant(P<0.05).Conclusion:Oral-facial acupressure combined with OPT can effectively improve articulation clarity in children with spastic cerebral palsy.This combined therapy is recommended for clinical promotion and application.

On the application of artificial bee colony (ABC) algorithm for optimization of well placements in fractured reservoirs;efficiency comparison with the particle swarm optimization (PSO) methodology

The application of a recent optimization technique,the artificial bee colony(ABC),was investigated in the context of finding the optimal well locations.The ABC performance was compared with the corresponding results from the particle swarm optimization(PSO)algorithm,under essentially similar conditions.Treatment of out-of-boundary solution vectors was accomplished via the Periodic boundary condition(PBC),which presumably accelerates convergence towards the global optimum.Stochastic searches were initiated from several random staring points,to minimize starting-point dependency in the established results.The optimizations were aimed at maximizing the Net Present Value(NPV)objective function over the considered oilfield production durations.To deal with the issue of reservoir heterogeneity,random permeability was applied via normal/uniform distribution functions.In addition,the issue of increased number of optimization parameters was address,by considering scenarios with multiple injector and producer wells,and cases with deviated wells in a real reservoir model.The typical results prove ABC to excel PSO(in the cases studied)after relatively short optimization cycles,indicating the great premise of ABC methodology to be used for well-optimization purposes.

Chaotic Simulator for Bilevel Optimization of Virtual Machine Placements in Cloud Computing

The drastic increase in engineering system complexity has spurred the development of highly efficient optimization techniques.Many real-world optimization problems have been identified as bilevel/multilevel as well as multiobjective.The primary aim of this work is to present a framework to tackle the bilevel virtual machine(VM)placement problem in cloud systems.This is done using the coupled map lattice(CML)approach in conjunction with the Stackelberg game theory and weighted-sum frameworks.The VM placement problem was modified from the original multiobjective(MO)problem to an MO bilevel formulation to make it more realistic albeit more complicated.Additionally comparative analysis on the performance of the CML approach was carried out against the particle swarm optimization method.A new bilevel metric called the cascaded hypervolume indicator is introduced and applied to measure the dominance of the solutions produced by both methods.Detailed analysis on the computational results is presented.

Software defined satellite networks:A survey

In recent years,satellite networks have been proposed as an essential part of next-generation mobile communication systems.Software defined networking techniques are introduced in satellite networks to handle the growing challenges induced by time-varying topology,intermittent inter-satellite link and dramatically increased satellite constellation size.This survey covers the latest progress of software defined satellite networks,including key techniques,existing solutions,challenges,opportunities,and simulation tools.To the best of our knowledge,this paper is the most comprehensive survey that covers the latest progress of software defined satellite networks.An open GitHub repository is further created where the latest papers on this topic will be tracked and updated periodically.Compared with these existing surveys,this survey contributes from three aspects:(1)an up-to-date SDN-oriented review for the latest progress of key techniques and solutions in software defined satellite networks;(2)an inspiring summary of existing challenges,new research opportunities and publicly available simulation tools for follow-up studies;(3)an effort of building a public repository to track new results.

Distributed Adaptive Output Consensus of Unknown Heterogeneous Non-Minimum Phase Multi-Agent Systems

This article addresses the leader-following output consensus problem of heterogeneous linear multi-agent systems with unknown agent parameters under directed graphs.The dynamics of followers are allowed to be non-minimum phase with unknown arbitrary individual relative degrees.This is contrary to many existing works on distributed adaptive control schemes where agent dynamics are required to be minimum phase and often of the same relative degree.A distributed adaptive pole placement control scheme is developed,which consists of a distributed observer and an adaptive pole placement control law.It is shown that under the proposed distributed adaptive control scheme,all signals in the closed-loop system are bounded and the outputs of all the followers track the output of the leader asymptotically.The effectiveness of the proposed scheme is demonstrated by one practical example and one numerical example.

Report and Phylogeny of a Novel Euplotes Species from China:E.mazeii n.sp.,and Review of E.balteatus(Alveolata,Ciliophora)

The freshwater species,Euplotes mazeii n.sp.,and the marine species,E.balteatus(Dujardin,1841)Diesing,1850 were collected from China and investigated based on their living morphology,ciliary pattern,and small subunit ribosomal RNA(SSU rRNA)gene sequence data.Euplotes mazeii n.sp.was characterized by its small cell size((40-55)μm×(25-35)μm),nine frontoventral cirri,one marginal and two caudal cirri,seven dorsal kineties,and a double-eurystomus type of dorsal silverline system.Phylogenetic analyses based on molecular data confirmed the branching position of this new taxa within the genus Euplotes,with 5.01%(84 nucleotides)sequence variation,supporting the identification of a new species.We re-examined all described and supposedly conspecific populations and give a review of Euplotes balteatus.E.balteatus has been reported frequently;however,E.balteatus sensu Agamaliev,1968 is different from other populations in the number of marginal cirri or the type of silverline system,which suggests there might be a misidentification.The SSU rRNA gene sequences of two populations of E.balteatus from the studies of Chen et al.(2013)and Pan et al.(2012)differ from each other by more than 135 nucleotides,implying that the identity of the species currently associated with the SSU rRNA gene sequence in molecular databases requires further confirmation.