Trans-splenic puncture during percutaneous nephrolithotomy: Outcome spectrum of the same complication

AbstractPercutaneous nephrolithotomy is an endourologic technique commonly used in the management of nephrolithiasis. However, this procedure is not complication-free. Splenic injury is exceptionally rare with a reported rate of 1% from the total case load. We present herein two cases of splenic puncture during percutaneous nephrolithotomy that illustrate two different outcomes. In the first case, the patient remained asymptomatic and was discharged on her third post-operative day after removing the nephrostomy, without any sign of hemodynamic compromise. In the second case, the patient presented with hemodynamic instability and an abdominal computed tomography scan was done that showed free fluid in the peritoneal cavity. Emergency laparotomy was performed and revealed a deep peripheral laceration (20mm×5mm in length) that required splenectomy. After a thorough review of the existing literature, we could find only 11 other instances of injury to the spleen in which treatment outcomes were reported. Patient hemodynamic status was the main factor in deciding on the type of treatment

Regulatory Dynamics on Random Networks: Asymptotic Periodicity and Modularity

We study the dynamics of discrete-time regulatory networks on random digraphs. For this we define ensembles of deterministic orbits of random regulatory networks, and introduce some statistical indicators related to the long-term dynamics of the system. We prove that, in a random regulatory network, initial conditions converge almost surely to a periodic attractor. We study the subnetworks, which we call modules, where the periodic asymptotic oscillations are concentrated. We proof that those modules are dynamically equivalent to independent regulatory networks.Comment: 23 pages, 3 figure

Fast frequency support control in the GB power system using VSC-HVDC technology

A fast frequency support control scheme for voltage source converter based high-voltage direct-current (HVDC) links has been designed, simulated and experimentally implemented and validated. The effectiveness of the proposed scheme has been tested on simplified GB power system models with both averaged and switched converter models. System performance has been initially assessed using different software simulation platforms (PSCAD and MATLAB/Simulink). System validation has been carried out using an experimental test-rig. It is shown that simulation and experimental results agree on well when the fast frequency support provision is enabled. For completeness, the effectiveness of the control scheme has been tested for two contingency scenarios: (i) when a high-voltage alternating-current interlink in parallel with the HVDC link is disconnected, and (ii) for a substantial increase in system load

Input-output signal selection for damping of power system oscillations using wind power plants

AbstractDuring the last years wind power has emerged as one of the most important sources in the power generation share. Due to stringent Grid Code requirements, wind power plants (WPPs) should provide ancillary services such as fault ride-through and damping of power system oscillations to resemble conventional generation. Through an adequate selection of input–output signal pairs, WPPs can be effectively used to provide electromechanical oscillations damping. In this paper, different analysis techniques considering both controllability and observability measures and input–output interactions are compared and critically examined. Recommendations are drawn to select the best signal pairs available from WPPs to contribute to power oscillations damping. Control system design approaches including single-input single-output and multivariable control are considered. The recommendation of analysis techniques is justified through the tools usage in a test system including a WPP

Experimental evidence of a natural parity state in 26^{26}Mg and its impact to the production of neutrons for the s process

We have studied natural parity states in $^{26}$Mg via the $^{22}$Ne($^{6}$Li,d)$^{26}$Mg reaction. Our method significantly improves the energy resolution of previous experiments and, as a result, we report the observation of a natural parity state in $^{26}$Mg. Possible spin-parity assignments are suggested on the basis of published $\gamma$-ray decay experiments. The stellar rate of the $^{22}$Ne($\alpha$,$\gamma$)$^{26}$Mg reaction is reduced and may give rise to an increase in the production of s-process neutrons via the $^{22}$Ne($\alpha$,n)$^{25}$Mg reaction.Comment: Published in PR

Acciones técnico-tácticas, factores contextuales y rendimiento deportivo de los equipos de concacaf durante la clasificación a Rusia 2018

The objective of this study was to determine which technical-tactical actions and contextual factors were related to the sports performance of the CONCACAF national teams during the qualifying phase of the 2018 World Cup Russia. The statistics of the 10 matches played by each of 6 national teams team were used (30 matches, 60 observations). The results indicate that the technical-tactical actions that were related to the sport performance and that differentiated the classified and unclassified teams, as well as the teams that obtained victories with the that tied or lost, were: the goals, shots on target, passes, and possession of the ball, also these teams got more victories when playing from home. In conclusion, the technical-tactical actions related to performance coincide with those reported in the literature, moreover, the fact of playing at home represented an advantage for the teams.El objetivo de este estudio fue determinar cuáles acciones técnico-tácticas y factores contextuales se relacionaron con el rendimiento deportivo de las selecciones absolutas de CONCACAF durante la fase clasificatoria a la Copa Mundial de Rusia 2018. Se utilizaron las estadísticas de los 10 partidos jugados por cada una de los 6 equipos nacionales (30 partidos, 60 observaciones). Los resultados indican que las acciones técnico-tácticas que se relacionaron con el rendimiento y que diferenciaron a los equipos clasificados y no clasificados, así como a los equipos que obtenían victorias con los que empataban o perdían, fueron: los goles, remates a marco realizados, pases, y posesión de balón, asimismo estos equipos consiguieron mayor cantidad de victorias cuando jugaban de locales. En conclusión, las acciones técnico-tácticas relacionadas con el rendimiento coinciden con las reportadas en la literatura, además, el hecho de jugar de local representó una ventaja para los equipos

Independent measurement of the Hoyle state β\beta feeding from 12B using Gammasphere

Using an array of high-purity Compton-suppressed germanium detectors, we performed an independent measurement of the $\beta$-decay branching ratio from $^{12}\mathrm{B}$ to the second-excited (Hoyle) state in $^{12}\mathrm{C}$. Our result is $0.64(11)\%$, which is a factor $\sim 2$ smaller than the previously established literature value, but is in agreement with another recent measurement. This could indicate that the Hoyle state is more clustered than previously believed. The angular correlation of the Hoyle state $\gamma$ cascade has also been measured for the first time. It is consistent with theoretical predictions