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Five-year outcomes of laparoscopic sleeve gastrectomy as a primary procedure for morbid obesity:A prospective study

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World Journal of Gastrointestinal Surgery 2017年第4期9卷 109-117页

作者： carlos Hoyuela department of General and digestive Surgery Hospital PlatóUniversitat Autònoma de Barcelona08006 BarcelonaSpain

AIM To prospectively evaluate the postoperative morbimortality and weight loss evolution of patients who underwent a laparoscopic sleeve gastrectomy(LSG) as a primary bariatric procedure during 5 years of follow-up. METHOdS Since 2006,data from patients undergoing a highly restrictive primary LSG have been prospectively registered in a database and analysed. Preoperative co-morbid conditions,operating time,hospital stay,early and late complications rate and evolution of weight loss after 5 years of follow-up were *** A total of 156 patients were included,74.3% of whom were women. The mean age was 43.2 ± 13.1 years and the mean body mass index(BMI) was 41.5 ± 7.9 kg/m^2. Seventy patients(44.8%) presented a BMI under 40 kg/m^2. The mortality rate was 0%. The leakage rate was 1.2%,and the total 30-d morbidity rate was 5.1%(8/156). With a mean follow-up of 32.7 ± 28.5(range 6-112) mo,the mean percent of excess of weight loss(%EWL) was 82.0 ± 18.8 at 1 year,76.7 ± 21.3 at 3 years and 60.3 ± 28.9 at 5 years. The mean percent of excess of BMI loss(%EBMIL) was 94.9 ± 22.4 at 1 year,89.4 ± 27.4 at 3 years and 74.8 ± 29.4 at 5 years. Patients with preoperative BMI less than 40 kg/m^2 achieved greaterweight loss than did the overall study population. diabetes remitted in 75% of the patients and HTA improved in 71.7%. CPAP masks were withdrawn in all patients with obstructive sleep *** LSG built with a narrow 34 F bougie and starting 3 cm from the pylorus proved to be safe and highly effective in terms of weight loss as a stand-alone procedure,particularly in patients with a preoperative BMI lower than 40 kg/m^2.

关键词： Sleeve gastrectomy Morbid obesity Bariatric surgery Obesity surgery Laparoscopy Long-term results 5-year results

A LoRa-based protocol for connecting IoT edge computing nodes to provide small-data-based services

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digital Communications and Networks 2022年第3期8卷 257-266页

作者： Kiyoshy Nakamura Pietro Manzoni Alessandro Redondi Edoardo Longo Marco Zennaro Juan-carlos Cano carlos T.Calafate Universitat Politécnica de Valéncia ValenciaSpain Abdus Salam International Centre for Theoretical Physics(ICTP) TriesteItaly Politecnico di Milano MilanItaly

data is becoming increasingly *** regularly interact with a variety of structured data,ranging from SQLite databases on the phone to personal sensors and open government ***“digital traces left by individuals through these interactions”are sometimes referred to as“small data”.Examples of“small data”include driving records,biometric measurements,search histories,weather forecasts and usage *** this paper,we present a flexible protocol called LoRaCTP,which is based on LoRa technology that allows data“chunks”to be transferred over large distances with very low energy *** provides all the mechanisms necessary to make LoRa transfer reliable by introducing a lightweight connection setup and allowing the ideal sending of an as-long-as necessary data *** designed this protocol as communication support for small-data edge-based IoT solutions,given its stability,low power usage,and the possibility to cover long *** evaluated our protocol using various data content sizes and communication distances to demonstrate its performance and reliability.

关键词： Small data Edge computing LoRa IoT

Spectral/hp element methods:Recent developments, applications, and perspectives

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Journal of Hydrodynamics 2018年第1期30卷 1-22页

作者： Hui Xu Chris d.Cantwell carlos Monteserin Claes Eskilsson Allan P.Engsig-Karup Spencer J.Sherwin department of Aeronautics Imperial College London department of Applied Mathematics and Computer Science Technical University of Denmark department of Civil Engineering Aalborg University division Safety and Transport Research Institutes of Sweden (RISE) Center for Energy Resources Engineering (CERE) Technical University of Denmark

The spectral/hp element method combines the geometric flexibility of the classical h-type finite element technique with the desirable numerical properties of spectral methods, employing high-degree piecewise polynomial basis functions on coarse finite element-type meshes. The spatial approximation is based upon orthogonal polynomials, such as Legendre or Chebychev polynomials,modified to accommodate a C~0-continuous expansion. Computationally and theoretically, by increasing the polynomial order p,high-precision solutions and fast convergence can be obtained and, in particular, under certain regularity assumptions an exponential reduction in approximation error between numerical and exact solutions can be achieved. This method has now been applied in many simulation studies of both fundamental and practical engineering flows. This paper briefly describes the formulation of the spectral/hp element method and provides an overview of its application to computational fluid dynamics. In particular, it focuses on the use of the spectral/hp element method in transitional flows and ocean engineering. Finally, some of the major challenges to be overcome in order to use the spectral/hp element method in more complex science and engineering applications are discussed.

关键词： High-precision spectral/hp elements continuous Galerkin method discontinuous Galerkin method implicit large eddy simulation

Zeckendorf representations with at most two terms to x-coordinates of Pell equations

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Science China Mathematics 2020年第4期63卷 627-642页

作者： carlos A.Gómez Florian Luca departamento de Matematicas Universidad del ValleCali 25360Colombia School of Mathematics University of the WitwatersrandWits 2050South Africa Max Planck Institute for Mathematics Bonn 53111Germany department of Mathematics Faculty of SciencesUniversity of OstravaOstrava 70103Czech Republic

In this paper,we find all positive squarefree integers d satisfying that the Pell equation X^2-d Y^2=±1 has at least two positive integer solutions(X,Y)and(X′,Y′)such that both X and X′have Zeckendorf representati... 详细信息

关键词： Pell equation Fibonacci numbers lower bounds for linear forms in logarithms reduction method

Virtual Conductance Based Cascade Voltage Controller for VSCs in Islanded Operation Mode

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1704-1713页

作者： Francisco Jesús Matas-díaz Manuel Barragán-Villarejo Juan carlos Olives-Camps Juan Manuel Mauricio JoséMaría Maza-Ortega department of Elec‐trical Engineering Universidad de SevillaSeville 41092Spain

Voltage source converters have become the main enabler for the integration of distributed energy resources in *** the case of islanded operation,these devices normally set the amplitude and frequency of the network voltage by means of a cascade controller composed of an outer voltage control loop and an inner current control *** strategies to compute the gains of both control loops have been proposed in the literature in order to obtain a fast and decoupled response of the voltages at the point of common *** paper proposes an alternative and simple methodology based on the introduction of a virtual conductance in the classic cascade *** strategy allows to design each control loop independently,obtaining a closed-loop response of a first-order *** this way,the gains of each control loop are easily derived from the parameters of the LC coupling filter and the desired closed-loop time ***,a state observer is included in the controller to estimate the inductor current of the LC filter in order to reduce the number of required measurements.A laboratory testbed is used to validate and compare the proposed *** experimental results demonstrate the effectiveness of the proposal both in steady-state and transient regimes.

关键词： Voltage source converter microgrid cascade controller virtual conductance

Additive engineering for stable halide perovskite solar cells

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Journal of Energy Chemistry 2021年第9期30卷 599-634页

作者： carlos Pereyra Haibing Xie Mónica Lira-Cantu Catalan Institute of Nanoscience and Nanotechnology(ICN2) CSIC and the Barcelona Institute of Science and Technology(BIST).Building ICN2Campus UAB E-08193BellaterraBarcelonaSpain

Halide perovskite solar cells(PSCs)have already demonstrated power conversion efficiencies above 25%,which makes them one of the most attractive photovoltaic ***,one of the main bottlenecks towards their commercialization is their long-term stability,which should exceed the 20-year *** engineering is an effective pathway for the enhancement of device *** applied as organic or inorganic compounds,improve crystal grain growth enhancing power conversion *** interaction of their functional groups with the halide perovskite(HP)absorber,as well as with the transport layers,results in defect passivation and ion immobilization improving device performance and *** this review,we briefly summarize the different types of additives recently applied in PSC to enhance not only efficiency but also long-term *** discuss the different mechanism behind additive engineering and the role of the functional groups of these additives for defect *** emphasis is given to their effect on the stability of PSCs under environmental conditions such as humidity,atmosphere,light irradiation(UV,visible)or heat,taking into account the recently reported ISOS *** also discuss the relation between deep-defect passivation,non-radiative recombination and device efficiency,as well as the possible relation between shallow-defect passivation,ion immobilization and device operational ***,insights into the challenge and criteria for additive selection are provided for the further stability enhancement of PSCs.

关键词： Additives Additive engineering Perovskite solar cells defect passivation Shallow defect deep defect Stability

3d non-stationary wideband circular tunnel channel models for high-speed train wireless communication systems

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Science China(Information Sciences) 2017年第8期60卷 189-201页

作者： Yu LIU Cheng-Xiang WANG carlos LOPEZ Xiaohu GE Shandong Provincial Key Lab of Wireless Communication Technologies Shandong University Institute of Sensors Signals and Systems School of Engineering & Physical Sciences Heriot-Watt University department of Electronics and Information Engineering Huazhong University of Science and Technology

This paper proposes three-dimensional(3d) non-stationary wideband circular geometry-based stochastic models(GBSMs) for high-speed train(HST) tunnel scenarios. Considering single-bounced(SB)and multiple-bounced(MB) components from the tunnel’s internal surfaces, a theoretical channel model is first established. Then, the corresponding simulation model is developed using the method of equal volume(MEV)to calculate discrete angular parameters. Based on the proposed 3d GBSMs, important time-variant statistical properties are investigated, such as the temporal autocorrelation function(ACF), spatial cross-correlation function(CCF), and space-doppler(Sd) power spectrum density(PSd). Results indicate that all statistical properties of the simulation model, verified by simulation results, can match well those of the theoretical *** statistical properties of the proposed 3d GBSMs are further validated by relevant measurement data,demonstrating the flexibility and utility of our proposed tunnel GBSMs.

关键词： non-stationary statistical properties tunnel channel model GBSM channel measurement

Fluid dynamics analysis and pyrolysis of brewer’s spent grain in a spouted bed reactor

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Particuology 2019年第1期17卷 199-207页

作者： Marcos A.S. Barrozo Lidja d.M.S. Borel Taísa S. Lira carlos H. Ataíde School of Chemical Engineering Federal University of UberlandiaBrazil department of Engineering and Technologies Federal University of Espirito SantoBrazil

Brewer’s spent grain (BSG) is a large-scale agroindustrial waste that could be more efficiently utilized. This waste is composed of lignocellulosic material and so may serve as a good source of biomass for thermochemical conversion. The present study investigated the fluid dynamics behavior of mixtures of sand and BSG in a spouted bed to assess the viability of the thermochemical conversion of this biomass via fast pyrolysis. Fluid dynamics analyses were performed while varying the mass fraction of BSG (6–80%) and the static bed height (6.6–13.4 cm). Empirical equations for predicting the minimum spouting conditions and the mixing index were obtained using a regression technique, and the selected fluid dynamics parameters were employed in the spouted bed pyrolysis. The bio-oil resulting from this process was rich in phenolic compounds, various nitrogenated compounds (representing precursors for pharmaceuticals) and long-chain hydrocarbons. The products obtained from the analytical and spouted bed pyrolysis processes were also compared.

关键词： Brewer’s spent grain Agroindustrial residue Spouted bed Fast pyrolysis Particle mixing

digestive and breast cancer patients managed during the first wave of COVId-19 pandemic:Short and middle term outcomes

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World Journal of Methodology 2024年第2期14卷 107-126页

作者： Jacobo Trébol Ana Carabias-Orgaz María Carmen Esteban-Velasco Asunción García-Plaza Juan Ignacio González-Munoz Ana Belén Sánchez-Casado Felipe carlos Parreno-Manchado Marta Eguía-Larrea José Antonio Alcázar-Montero Cirugía General y del Aparato digestivo Complejo Asistencial Universitario de SalamancaSalamanca 37007SalamancaSpain Cirugía Universidad de SalamancaSalamanca 37007SalamancaSpain Oftalmología Complejo Asistencial Universitario de SalamancaSalamanca 37007SalamancaSpain

BACKGROUNd The first wave of coronavirus disease 2019(COVId-19)pandemic in Spain lasted from middle March to the end of June *** population was subjected to lockdown periods and scheduled surgeries were discontinued or reduced during variable *** our centre,we managed patients previously and newly diagnosed with *** established a strategy based on limiting perioperative social contacts,preoperative screening(symptoms and reverse transcriptionpolymerase chain reaction)and creating separated in-hospital COVId-19-free pathways for non-infected *** also adopted some practice modifications(surgery in different facilities,changes in staff and guidelines,using continuously changing personal protective equipment…),that supposed new *** To analyse cancer patients with a decision for surgery managed during the first wave,focalizing on outcomes and pandemic-related *** We prospectively included adults with a confirmed diagnosis of colorectal,oesophago-gastric,liver-pancreatic or breast cancer with a decision for surgery,regardless of whether they ultimately underwent *** analysed short-term outcomes[30-d postoperative morbimortality and severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection]and outcomes after 3 years(adjuvant therapies,oncological events,death,SARS-CoV-2 infection and vaccination).We also investigated modifications to usual *** From 96 included patients,seven didn’t receive treatment that period and four never(3 due to COVId-19).Operated patients:28 colon and 21 rectal cancers;laparoscopy 53.6%/90.0%,mortality 3.57%/0%,major complications 7.04%/25.00%,anastomotic leaks 0%/5.00%,3-years disease-free survival(dFS)82.14%/52.4%and overall survival(OS)78.57%/76.2%.Six liver metastases and six pancreatic cancers:no mortality,one major complication,three grade A/B liver failures,one bile leak;3-year dFS 0%/33.3%and OS 50.0%/33.3%(liver metastases/pancreatic carcinoma).5 g

关键词： COVId-19 SARS-CoV-2 Colon cancer Rectal cancer Breast cancer Liver cancer Pancreatic cancer Gastric cancer Oesophageal cancer Surgery