109 research outputs found

    Liver transplantation in a patient with complete portal vein thrombosis, is there a surgical way out? A case report

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    Introduction: Due to the complexity of the surgical procedure portal vein thrombosis (PVT) has long been considered an absolute contraindication to liver transplantation (LT). The presence of a large splenorenal shunt (SRS) could make portal anastomosis a valid option.Presentation of case: We report the case of a 37-year-old female patient with Grade III PVT and a large SRS, who underwent orthotopic LT. Liver was implanted using a 1992-Belghiti piggyback technique and portal anastomosis was performed using the large spleno-renal shunt. We observed good graft reperfusion and postoperative Doppler ultrasound showed normal portal vein flow. She was discharged on postoperative day 7, with an excellent graft function. At six months follow-up, patient is alive with normal hepatic vascularization.Discussion: Due to paucity of reports, there is currently no consensus on the indication to LT and/or surgical technique. In the present case, once the transplant benefit was evaluated, the Grade III PVT was not considered a contraindication to LT.Conclusion: The presence of a Grade III PVT associated with a large SRS should not be considered a contraindication for LT, and the use of the shunt vein should be considered a feasible option to perform portal anastomosis. (C) 2016 The Author(s). Published by Elsevier Ltd on behalf of IJS Publishing Group Ltd

    Some results on thermal stress of layered plates and shells by using Unified Formulation

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    This work presents some results on two-dimensional modelling of thermal stress problems in multilayered structures. The governing equations are written by referring to the Unified Formulation (UF) introduced by the first author. These equations are obtained in a compact form, that doesn't depend on the order of expansion of variables in the thickness direction or the variable description (layer-wise models and equivalent single layers models). Classical and refined theories based on the Principle of Virtual Displacements (PVD) and advanced mixed theories based on the Reissner Mixed Variational Theorem (RMVT) are both considered. As a result, a large variety of theories are derived and compared. The temperature profile along the thickness of the plate/shell is calculated by solving the Fourier's heat conduction equation. Alternatively, thermo-mechanical coupling problems can be considered, in which the thermal variation is influenced by mechanical loading. Exact closed-form solutions are provided for plates and shells, but also the applications of the Ritz method and the Finite Element Method (FEM) are presented

    Hardware prototyping and validation of a W-ΔDOR digital signal processor

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    Microwave tracking, usually performed by on ground processing of the signals coming from a spacecraft, represents a crucial aspect in every deep-space mission. Various noise sources, including receiver noise, affect these signals, limiting the accuracy of the radiometric measurements obtained from the radio link. There are several methods used for spacecraft tracking, including the Delta-Differential One-Way Ranging (ΔDOR) technique. In the past years, European Space Agency (ESA) missions relied on a narrowband ΔDOR system for navigation in the cruise phase. To limit the adverse effect of nonlinearities in the receiving chain, an innovative wideband approach to ΔDOR measurements has recently been proposed. This work presents the hardware implementation of a new version of the ESA X/Ka Deep Space Transponder based on the new tracking technique named Wideband ΔDOR (W-ΔDOR). The architecture of the new transponder guarantees backward compatibility with narrowband ΔDOR

    Determinants of weight, psychological status, food contemplation and lifestyle changes in patients with obesity during the COVID-19 lockdown: a nationwide survey using multiple correspondence analysis

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    Introduction The corona virus disease 2019 (COVID-19) pandemic forced most of the Italian population into lockdown from 11 March to 18 May 2020. A nationwide survey of Italian Clinical Nutrition and Dietetic Services (Obesity Centers or OCs) was carried out to assess the impact of lockdown restrictions on the physical and mental wellbeing of patients with obesity (PWO) who had follow-up appointments postponed due to lockdown restrictions and to compare determinants of weight gain before and after the pandemic. Methods We designed a structured 77-item questionnaire covering employment status, diet, physical activity and psychological aspects, that was disseminated through follow-up calls and online between 2 May and 25 June 2020. Data were analyzed by multiple correspondence analysis (MCA) and multiple linear regression. Results A total of 1,232 PWO from 26 OCs completed the questionnaires (72% female, mean age 50.2 +/- 14.2 years; mean BMI 34.7 +/- 7.6 kg/m(2); 41% obesity class II to III). During the lockdown, 48.8% gained, 27.1% lost, while the remainder (24.1%) maintained their weight. The mean weight change was +2.3 +/- 4.8 kg (in weight gainers: +4.0 +/- 2.4 kg; +4.2% +/- 5.4%). Approximately 37% of participants experienced increased emotional difficulties, mostly fear and dissatisfaction. Sixty-one percent reduced their physical activity (PA) and 55% experienced a change in sleep quality/quantity. The lack of online contact (37.5%) with the OC during lockdown strongly correlated with weight gain (p < 0.001). Using MCA, two main clusters were identified: those with unchanged or even improved lifestyles during lockdown (Cluster 1) and those with worse lifestyles during the same time (Cluster 2). The latter includes unemployed people experiencing depression, boredom, dissatisfaction and increased food contemplation and weight gain. Within Cluster 2, homemakers reported gaining weight and experiencing anger due to home confinement. Conclusions Among Italian PWO, work status, emotional dysregulation, and lack of online communication with OCs were determinants of weight gain during the lockdown period

    Perspectives and Integration in SOLAS Science

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    Why a chapter on Perspectives and Integration in SOLAS Science in this book? SOLAS science by its nature deals with interactions that occur: across a wide spectrum of time and space scales, involve gases and particles, between the ocean and the atmosphere, across many disciplines including chemistry, biology, optics, physics, mathematics, computing, socio-economics and consequently interactions between many different scientists and across scientific generations. This chapter provides a guide through the remarkable diversity of cross-cutting approaches and tools in the gigantic puzzle of the SOLAS realm. Here we overview the existing prime components of atmospheric and oceanic observing systems, with the acquisition of ocean–atmosphere observables either from in situ or from satellites, the rich hierarchy of models to test our knowledge of Earth System functioning, and the tremendous efforts accomplished over the last decade within the COST Action 735 and SOLAS Integration project frameworks to understand, as best we can, the current physical and biogeochemical state of the atmosphere and ocean commons. A few SOLAS integrative studies illustrate the full meaning of interactions, paving the way for even tighter connections between thematic fields. Ultimately, SOLAS research will also develop with an enhanced consideration of societal demand while preserving fundamental research coherency. The exchange of energy, gases and particles across the air-sea interface is controlled by a variety of biological, chemical and physical processes that operate across broad spatial and temporal scales. These processes influence the composition, biogeochemical and chemical properties of both the oceanic and atmospheric boundary layers and ultimately shape the Earth system response to climate and environmental change, as detailed in the previous four chapters. In this cross-cutting chapter we present some of the SOLAS achievements over the last decade in terms of integration, upscaling observational information from process-oriented studies and expeditionary research with key tools such as remote sensing and modelling. Here we do not pretend to encompass the entire legacy of SOLAS efforts but rather offer a selective view of some of the major integrative SOLAS studies that combined available pieces of the immense jigsaw puzzle. These include, for instance, COST efforts to build up global climatologies of SOLAS relevant parameters such as dimethyl sulphide, interconnection between volcanic ash and ecosystem response in the eastern subarctic North Pacific, optimal strategy to derive basin-scale CO2 uptake with good precision, or significant reduction of the uncertainties in sea-salt aerosol source functions. Predicting the future trajectory of Earth’s climate and habitability is the main task ahead. Some possible routes for the SOLAS scientific community to reach this overarching goal conclude the chapter

    Fine-grain reconfigurable functional unit for embedded processors

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    In standard word-oriented microprocessors, the processing of short data decreases the computation performance. In order to overcome this issue various methods based on reconfigurable architectures have been presented in the literature [1] [2] [3]. These structures are normally composed by an array of elementary reconfigurable cells. A common solution for elementary reconfigurable cells realization is based on Look-Up Tables (LUTs). In [4] [5] the authors proposed a new Reconfigurable Functional Unit (RFU) based on full adders and reprogrammable interconnects named ADAPTO. The final aim is to obtain a new structure that requires less silicon area and power, being ever faster than the "traditional" solutions. In this paper we present the main characteristics of the proposed structure evaluating its performance (in terms of speed-up and complexity) when integrated in an embedded processor. © 2011 IEEE

    Design and Requirements for a Mobile Robot for Team Cooperation

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