Lagrangian phase transitions in nonequilibrium thermodynamic systems

In previous papers we have introduced a natural nonequilibrium free energy by considering the functional describing the large fluctuations of stationary nonequilibrium states. While in equilibrium this functional is always convex, in nonequilibrium this is not necessarily the case. We show that in nonequilibrium a new type of singularities can appear that are interpreted as phase transitions. In particular, this phenomenon occurs for the one-dimensional boundary driven weakly asymmetric exclusion process when the drift due to the external field is opposite to the one due to the external reservoirs, and strong enough.Comment: 10 pages, 2 figure

Radioterapia śródoperacyjna u chorych na nowotwory złośliwe przewodu pokarmowego: współczesne wyniki leczenia skojarzonego

Abstract The integration of intraoperative radiotherapy (IORT) into the multimodal treatment of gastrointestinal cancer is feasible and leads to high rates of local control. In-field tumoral control using IORT-containing strategies can be achieved in over 90% of most cases, regardless of the site or status of the tumor (primary or recurrent). Electron beam IORT, or intraoperative electron radiation therapy, is the dominant technology used in institutions reporting data in publications the 21st century. Neither surgery nor systemic therapy is compromised by the integration of IORT-containing radiotherapy.Wprowadzenie radioterapii śródoperacyjnej (IORT, integration of intraoperative radiotherapy) do schematów leczenia skojarzonego u chorych na nowotwory przewodu pokarmowego jest możliwe i może prowadzić do poprawy wyleczalności miejscowej. Wyleczenie w objętości napromienianej można osiągnąć w około 90% przypadków leczonych schematami z udziałem IORT, niezależnie od lokalizacji i statusu guza (pierwotny lub nawrotowy). Terapia IORT wiązką elektronową (śródoperacyjna radioterapia elektronowa) jest dominującą techniką stosowaną w ośrodkach publikujących najnowsze doniesienia. Leczenie z wykorzystaniem IORT nie zastępuje jednak ani chirurgii, ani postępowania systemowego

Macroscopic fluctuation theory

Stationary non-equilibrium states describe steady flows through macroscopic systems. Although they represent the simplest generalization of equilibrium states, they exhibit a variety of new phenomena. Within a statistical mechanics approach, these states have been the subject of several theoretical investigations, both analytic and numerical. The macroscopic fluctuation theory, based on a formula for the probability of joint space-time fluctuations of thermodynamic variables and currents, provides a unified macroscopic treatment of such states for driven diffusive systems. We give a detailed review of this theory including its main predictions and most relevant applications.Comment: Review article. Revised extended versio

Limb-sparing management with surgical resection, external-beam and intraoperative electron-beam radiation therapy boost for patients with primary soft tissue sarcoma of the extremity: a multicentric pooled analysis of long-term outcomes

Background or purpose: A joint analysis of data from three contributing centres within the intraoperative electron-beam radiation therapy (IOERT) Spanish program was performed to investigate the main contributions of IORT to the multidisciplinary treatment of high-risk extremity soft tissue sarcoma (STS). Methods and materials: Patients with an histologic diagnosis of primary extremity STS, with absence of distant metastases, undergoing limb-sparing surgery with radical intent, external beam radiotherapy (median dose 45 Gy) and IOERT (median dose 12.5 Gy) were considered eligible for participation in this study. Results: From 1986-2012, a total of 159 patients were analysed in the study from three Spanish institutions. With a median follow-up time of 53 months (range 4-316 years), 5-year local control (LC) was 82 %. The 5-year IOERT in-field control, disease-free survival (DFS) and overall survival (OS) were 86, 62 and 72 %, respectively. On multivariate analysis, only microscopically involved margin (R1) resection status retained significance in relation to LC (HR 5.20, p < 0.001). With regard to IOERT in-field control, incomplete resection (HR 4.88, p = 0.001) and higher IOERT dose (≥ 12.5 Gy; HR 0.32, p = 0.02) retained a significant association in multivariate analysis. Conclusion: From this joint analysis emerges the fact that an IOERT dose ≥ 12.5 Gy increases the rate of IOERT in-field control, but DFS remains modest, given the high risk of distant metastases. Intensified local treatment needs to be tested in the context of more efficient concurrent, neo- and adjuvant systemic therapy

Density profiles of dark matter haloes: diversity and dependence on environment

(Abridged) We study the outer density profiles of dark matter haloes predicted by a generalized secondary infall model and observed in a N-body cosmological simulation of a \Lambda CDM model. We find substantial systematic variations in shapes and concentrations of the halo profiles as well as a strong correlation of the profiles with the environment. In the N-body simulation, the average outer slope of the density profiles, \beta (\rho\propto r^{-\beta}), of isolated haloes is \approx 2.9; 68% of these haloes have values of \beta between 2.5 and 3.8. Haloes in dense environments of clusters are more concentrated and exhibit a broad distribution of \beta with values larger than for isolated haloes . Contrary to what one may expect, the haloes contained within groups and galaxy systems are less concentrated and have flatter outer density profiles than the isolated haloes. The concentration decreases with M_h, but its scatter for a given mass is substantial. The mass and circular velocity of the haloes are strongly correlated: M_h \propto V_m^{\alpha} with \alpha ~ 3.3 (isolated) and ~3.5 (haloes in clusters). For M_h=10^12M_sun the rms deviations from these relations are \Delta logM_h=0.12 and 0.18, respectively. Approximately 30% of the haloes are contained within larger haloes or have massive companions (larger than ~0.3 the mass of the current halo) within 3 virial radii. The remaining 70% of the haloes are isolated objects. The distribution of \beta as well as the concentration-mass and M_h-V_m relations for the isolated haloes agree very well with the predictions of our seminumerical approach which is based on a generalization of the secondary infall model and on the extended Press-Schechter formalism.Comment: 14 pages, 11 figures included, uses mn.sty, accepted by MNRAS. Minor modifications, new and updated reference

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Imaging opportunities for treatment planning in intraoperative electron beam radiotherapy (IOERT): Developments in the context of RADIANCE system

AimThe purpose of this report is to store the information of the pre-planning and compare this data with the actual data of the procedure.BackgroundCurrently, intraoperative electron beam radiotherapy clinical practice lacks a treatment planning system.Materials and methodsThe RADIANCE concept approaches treatment planning by providing the user with a navigation platform based on a three-dimensional imaging system in which the radiation oncologist can target the tumor and risk areas in different sections (axial, coronal, sagittal), while a volume rendering engine displays a 3D image that is automatically updated as we make any changes of the space. Finally, the user may select the parameters of the applicator, energy and dose of treatment to optimize the procedure. Six cases are clinically described and illustrated.ResultsRADIANCE is a useful tool in planning IOERT. Tumor segmentation and risk areas with minimal guide in the selection of parameters for the applicator. Complex locations are challenging, where the experience and skill of the radiation oncologist is necessary to optimize the process. New developments include imaging innovated uses. Intraoperative imaging will approach reality and allow real time, dosimetry estimations, stereotactic recognition of patient and tumor bed position, will guide automatization of radiation beam recognition and pre-robotic arrangements with linear accelerator movements.ConclusionsRADIANCE offers a new imaging expansion for IOERT, in the context of a multidisciplinary approach to optimize and define the treatment parameters to approximate the actual treatment radiotherapy procedure

Intraoperative radiation therapy, opportunities for clinical practice normalization: MEDTING, a scientific platform

AimTo use a platform to analyze a subgroup specialized in evaluation of patients candidates to IOERT.BackgroundMedting is a project that was initiated to support daily clinical activity, knowledge management and medical education by sharing information with other physicians. The project began at the “Hospital General Universitario Gregorio Marañón”, which has a dedicated oncology physician's multi-specialist committee. There are many scientific social networks all over the world. Medting is the only platform that specializes in healthcare and has been developed for hospital purposes.Materials and methodsMedting brings all together the relevant clinical information from electronic medical records and picture archiving about the patient to study. Subplatform Medting-IORT was created on February 2, 2012 at the Hospital General Universitario Gregorio Marañon. It has 23 members, have been registered 18 cases with 238 multimedia images.ResultsMedting started with 28 physicians and five departments. After 6 months, proof of concept period, there are 225 physicians, more than 120 medical students and 39 departments in 3 hospitals using the scientific social network. Furthermore, the project is being extended on three more hospitals in Madrid.ConclusionMedting gives the opportunity to oncology physicians to access all relevant clinical information with the ability to discuss case notes and view images at any time. The impact of the Medting platform in a subgroup working team to evaluate IOERT patients candidates is included in the analysis. The use of a constantly updated repository based on real cases and the documentation of the internal activity of the tumor committee beyond the medical record, has become an extraordinary tool for teaching, training and learning

Intraoperative radiation therapy, opportunities for clinical practice normalization: MEDTING, a scientific platform

AbstractAimTo use a platform to analyze a subgroup specialized in evaluation of patients candidates to IOERT.BackgroundMedting is a project that was initiated to support daily clinical activity, knowledge management and medical education by sharing information with other physicians. The project began at the “Hospital General Universitario Gregorio Marañón”, which has a dedicated oncology physician's multi-specialist committee. There are many scientific social networks all over the world. Medting is the only platform that specializes in healthcare and has been developed for hospital purposes.Materials and methodsMedting brings all together the relevant clinical information from electronic medical records and picture archiving about the patient to study. Subplatform Medting-IORT was created on February 2, 2012 at the Hospital General Universitario Gregorio Marañon. It has 23 members, have been registered 18 cases with 238 multimedia images.ResultsMedting started with 28 physicians and five departments. After 6 months, proof of concept period, there are 225 physicians, more than 120 medical students and 39 departments in 3 hospitals using the scientific social network. Furthermore, the project is being extended on three more hospitals in Madrid.ConclusionMedting gives the opportunity to oncology physicians to access all relevant clinical information with the ability to discuss case notes and view images at any time. The impact of the Medting platform in a subgroup working team to evaluate IOERT patients candidates is included in the analysis. The use of a constantly updated repository based on real cases and the documentation of the internal activity of the tumor committee beyond the medical record, has become an extraordinary tool for teaching, training and learning