检索结果-南通市图书馆

Survival of patients with hepatopulmonary syndrome related to cirrhotic and non-cirrhotic(schistosomiasis)portal hypertension

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Hepatology 2025年第2期17卷 65-71页

作者： Melissa M Rolim liana G Farsoun Carlos F luna Brivaldo Markman-Filho Paulo Querette Edmundo P lopes Ana l Domingues Postgraduate Program in Tropical Medicine Center of Medical SciencesUniversidade Federal de PernambucoRecife 50670901PernambucoBrazil Faculdade de Medicina UniNassau Grupo Ser EducacionalRecife 50100220PernambucoBrazil Statistics and Geoprocessing Center Institute Aggeu MagalhãesOswaldo Cruz FoundationRecife 50740465PernambucoBrazil Department of Cardiology Division Hospital das Clínicas/EBSERHUniversidade Federal de PernambucoRecife 50670901PernambucoBrazil Department of Internal Medicine Center of Medical SciencesUniversidade Federal de PernambucoRecife 50670901PernambucoBrazil Postgraduate Program in Translational Health Center of Medical SciencesUniversidade Federal de PernambucoRecife 50670901PernambucoBrazil Department of Gastroenterology Division Hospital das Clínicas/EBSERH-Universidade Federal de PernambucoRecife 50670901PernambucoBrazil

BACKGROUND The hepatosplenic schistosomiasis(HSS)with portal hypertension can cause vascular complications such as hepatopulmonary syndrome(HPS).HPS increases the risk of mortality in patients with cirrhosis;however,there is no data on the mortality of patients with HSS and *** To perform a survival analysis of patients with HPS related to cirrhotic and non-cirrhotic(schistosomiasis)portal *** From August 2023 to January 2024,medical records and the official mortality information service of 121 patients who participated in a cross-sectional study on HPS between 2010 and 2012 were *** curves were created using the Kaplan-Meier method,and comparisons were performed using the log-rank *** regression models estimated the hazard ratios(HR).RESUlTS Overall,data of 113 patients were analyzed;most(55.8%)had HSS and concomitant cirrhosis(HSS/cirrhosis).Meanwhile,HPS was present in 39(34.5%)*** occurred in 65 patients[57.5%];95%confidence interval(CI):48%-67%.The average time to death was lower in those with HPS when compared to those without HPS(3.37 years vs 5.65 years;P=0.017).According to the cause of liver disease,patients with HSS/cirrhosis died earlier,and their risk of death was twice as high compared with patients with HSS without cirrhosis(HR:2.17;95%CI:1.3-3.60;P=0.003).Meanwhile,there were no differences when comparing the two groups with and without HPS(HR:1.01;95%CI:0.59-1.73;P=0.967).CONClUSION Patients with HSS and concomitant cirrhosis had a lower survival rate,but there was no difference in survival regardless of the presence of HPS.

关键词： Schistosomiasis Portal hypertension Hepatopulmonary syndrome Survival Mortality Non-cirrhotic portal hypertension

Worker laying in leafcutter ant Acromyrmex subterraneus brunneus （Formicidae, Attini）

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2007年第2期14卷 157-163页

作者： ROBERTO S. CAMARGO luiz C. FORTI JUlIANE F. S. lopes NEWTON C. NORONHA ANGElO l. T. OTTATI Departamento de Producāo Vegetal FCA/UNESP Botucatu SP Campus Universitário Paulo VI Sāo Luis MA Brazil. Comportamento e Biologia Animal Instituto de Ciencias Biológicas Universidade Federal de Juiz de Fora Campus Universitário Martelos Juiz de Fora MG Campus Universitário Paulo VI Sāo Luis MA Brazil. Departamento de Entomologia Fitopatologia e Zoologia Agricola Escola Superior de Agricultura 'Luiz de Queiroz' Universidade de Sao Paulo Piracicaba SP Campus Universitário Paulo VI Sāo Luis MA Brazil. Departamento de Fitotecnia e Fitossanidade Universidade Estadual do Maranhāo Centro de Ciencias Agrenias Campus Universitário Paulo VI Sāo Luis MA Brazil.

We studied the process of offspring production in queenless colonies of Acromyrmex subterraneus brunneus, and particularly evaluated the ovary development of workers as a function of their age. For this, subcolonies were set up and evaluated at different periods of isolation from the queen （2, 4 and 6 months）, besides individually labeled age groups. The subcolonies were assessed according to offspring production and ovaries containing oocytes or not. The evaluations showed worker oviposition and development of males originating from worker-laid eggs. At 2 months＇ absence of the queen, eggs and larvae were found, with eggs in a higher proportion than larvae. After 4 months, the proportion of eggs had reduced while larvae had increased, and a pupa was found in one subcolony. At 6 months, besides a higher share of larvae, one pupa and one adult male were found. Dissection of workers revealed ovaries containing oocytes during the periods of evaluation. Only a group of medium-sized and large workers, 23.3%, 20.9% and 37.5% of the population from each period assessed in queenless subcolonies respectively, presented developed oocytes in the ovary. The same was observed in colonies with a queen, with 17.6%, 19.6% and 7.8% of the group of dissected workers from each time period, respectively. With respect to worker age, we observed by dissection of the ovary, that the greatest percentage of individuals with ovarioles containing oocytes occurred at 45 days （6 weeks） up to 90 days （12 weeks）. These results probably are associated with the workers reproduction and the laying of trophic and reproductive eggs in colonies with and without a queen; these eggs have distinct functions in each situation.

关键词： leafcutter ant queenless ant colonies reproduction conflict worker laying,worker reproduction

The nest architecture of the ant, Pheidole oxyops Forel, 1908 （Hymenoptera： Formicidae）

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2007年第5期14卷 437-442页

作者： luiz C. FORTI ROBERTO S. CAMARGO RICARDO T. FUJIHARA JUlIANE F. S. lopes laboratorio de Insetos Sociais-Praga Departamento de Producao Vegetal - Setor Defesa Fitossanitaria FCA/UNESP Botucatu SP Comportamento e Ecologia Animal Instituto de Ciencias Biologicas Universidade Federal de Juiz de Fora Campus Universitario Martelos Juiz de Fora MG Brazil

Pheidole oxyops builds subterranean nests, with an external architecture that is distinctive and easily recognizable by its wide and specific entrance hole, measuring up to 12.2 cm in diameter, denoting a pitfall-trap. In order to study the nests＇ internal architecture, seven nests were excavated; four were identified with neutral talc, while the others were cast in cement and then excavated. Measurements were made in order to gain a better understand- ing of their structures, and a photographic documentation was obtained as well. The excavations revealed that the nests are perpendicular relative to the ground, beginning with a cylindrical channel with a mean length of 13.5 cm, containing irregular formations, and whose diameter becomes progressively narrower until the first chamber is formed. As the channel continues, dish-like chambers appear, interconnected by channels that become progressively narrower and longer, while the chambers are arranged at greater distances from each other as nest depth increases. Both channels and chambers are located on the vertical projection of the entrance hole. Nests may reach a depth of up to 5.09 m, with a number of chambers ranging between 4 and 14.

关键词： chambers nest architecture Pheidole pitfall-trap

Resource management at the network edge for federated learning

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Digital Communications and Networks 2024年第3期10卷 765-782页

作者： Silvana Trindade luiz F.Bittencourt Nelson l.S.da Fonseca Institute of Computing State University of CampinasCampinasBrazil

Federated learning has been explored as a promising solution for training machine learning models at the network edge,without sharing private user *** limited resources at the edge,new solutions must be developed to leverage the software and hardware resources as the existing solutions did not focus on resource management for network edge,specially for federated *** this paper,we describe the recent work on resource manage-ment at the edge and explore the challenges and future directions to allow the execution of federated learning at the *** such as the discovery of resources,deployment,load balancing,migration,and energy effi-ciency are discussed in the paper.

关键词： Resource management Edge computing Federated learning Machine learning

Influence of physical and chemical factors during foraging and culture of the symbiont fungus in Atta sexdens rubropilosa （Hymenoptera： Formicidae）

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Insect Science 2007年第4期14卷 295-300页

作者： SANDRA S. VERZA luiz C. FORTI JUlIANE F. S. lopes ROBERTO S.CAMARGO CARlOS A. O. MATOS Departamento de Zoologia Instituto de Biociencias laboratrio de Insetos Sociais-Praga Departamento de Produ~~o Vegetal-Def-esa Fitossanitaria Faculdade de Ciencias Agronomicas UNESP-Sao Paulo State University Fazenda Experimental LageadoBotucatu SP Comportamento e Biologia Animal Instituto de Ciencias Biologicas UFJF-Universidade Federal de Juiz de ForaCampus Universitario Martelos Juiz de Fora MG Campus Experimental de Itapeva UNESP Itapeva SP Brazil

The aim of this paper is to investigate the influence of physical and chemical factors on transport and use of substrate for Atta sexdens rubropilosa workers. Three types of rectangular fragments were used to study the physical influence factors： filter paper with paraffin, filter paper without paraffin and polyester film. To study the chemical factors, some fragments were impregnated with organic extract of orange albedo, others were soaked with soybean oil and for the remaining ones nothing was applied. The fonowing parameters were evaluated：（i） attractiveness of substrate for transport and number of loading workers per treatment; （ii） foraged material incorporation; （iii） rejection by numbers of fragments deposited in the garbage or beside the fungus garden. All the polyester film fragments carried out to the fungus garden were subsequently rejected. We verified that chemical factors of the substrate were more quickly detected by the workers, whereas physical factors were used as a criterion in the decision-making to reject or accept the substrate collected.

关键词： Atta sexdens rubropilosa attractiveness behavior leaf-cutting ants substraterejection substrate selection

Inverter-Based Diesel Generator Emulator for the Study of Frequency Variations in a laboratory-Scale Autonomous Power System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy and Power Engineering 2013年第3期5卷 274-283页

作者： Miguel Torres luiz A. C. lopes Department of Electrical and Computer Engineering Concordia University Montreal Canada

This paper presents the modeling, simulation and practical implementation of an inverter-based diesel generator emulator. The main purpose of this emulator is for the study of frequency variations in diesel-based autonomous power systems in a laboratory environment where the operation of a real diesel generator is not possible. The emulator basically consists in a voltage source inverter with a second order output filter which voltage references are given by the model of the diesel generator. The control of the emulator is based on the digital signal processor TMS320F2812, where the mathematical models of the diesel generator and the control of the inverter are computed in real-time. Parameters for the model were obtained from commercially available components. Experimental results for different values of speed droop showed that the emulator achieves a satisfactory performance in the transient and stationary response. For the stationary response, the measured frequency deviates from theoretical values with a mean absolute error of: 0.06 Hz for 0% droop, 0.037 Hz for 3% droop, and 0.087 Hz for 5% droop. For the transient response, the measured frequency nadir deviates from simulations in: 0.05 Hz for 0% droop, 0.02 Hz for 3% droop, and 0.1 Hz for 5% droop.

关键词： Diesel Generator Emulator Inverter Frequency Control Mini-Grid

A Virtual Synchronous Machine to Support Dynamic Frequency Control in a Mini-Grid That Operates in Frequency Droop Mode

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy and Power Engineering 2013年第3期5卷 259-265页

作者： Miguel Torres luiz A. C. lopes Department of Electrical and Computer Engineering Concordia University Montreal Canada

This paper addresses the problem of dynamic frequency control in a diesel-based mini-grid. It is shown that a virtual synchronous machine (VSM) can support dynamic frequency control by adding virtual inertia and damping to the system. However, it is found that the typical formulation of damping power does not work properly when the grid forming gen-set operates in droop mode because of the unknown stabilization value of the grid frequency. As a solution to this problem, an estimator for the stabilization frequency that works in conjunction with the damping function of the VSM is proposed. Theoretical and experimental results provide evidence of a satisfactory performance of the proposed VSM with estimator for different values of the gen-set droop factor. The estimated stabilization frequency converges in approximately 2 s and the maximum frequency deviation during the transient is reduced in 34%, on average.

关键词： Frequency Control Mini-Grid Inverter Virtual Synchronous Machine

Housing flexibility problem： Review of recent limitations and solutions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Architectural Research 2018年第1期7卷 80-91页

作者： Sabine Ritter De Paris Carlos Nuno l. lopes Centro de Inovaco em Arquitectura e Modos de Habitar (CIAMH) University of Porto Porto 4150-564 Portugal

The economic, technological, and cultural transformations of our present society influence various scales of our daily lives. In housing, these transformations include changes in the family nucleus and the activities performed in living spaces. Housing flexibility seeks to meet the muitipte needs of users by changing their living spaces and functions. This study aims to explore housing flexibility through a review of relevant literature, discussion of valuable findings, and presentation of a contemporary panorama of the theme. Notions of flexibility are integrated to reinterpret the contemporary sense of dwelling. However, the lack of a well-defined concept of flexibility hinders the integration of methods and theories on the subject.

关键词： Housing Fiexibility Building

Virtual Synchronous Generator: A Control Strategy to Improve Dynamic Frequency Control in Autonomous Power Systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy and Power Engineering 2013年第2期5卷 32-38页

作者： Miguel Torres luiz A. C. lopes Department of Electrical and Computer Engineering Concordia University Montreal Canada

Ideally, diesel hybrid autonomous power systems would operate with high penetration of renewable energy sources such as wind and photovoltaic to minimize fuel consumption. However, since these are inherently intermittent and fluctuating, the grid-forming diesel engine generator sets are usually required to operate with larger amounts of spinning reserve, often at low loading conditions what tends to increases operating and maintenance costs. Frequency stability is of great concern in “small” systems, such as mini-grids, where any individual generator in-feed represents a substantial portion of the total demand. There, the initial rate of change of frequency is typically larger and a lower value of frequency can be reached in a shorter time than in conventional systems with all generation supplied by rotating machines, possibly resulting in under-frequency load shedding and tripping of renewable energy generators. The first part of this paper, discusses some general concepts regarding frequency stability in a diesel hybrid mini-grid and how energy storage systems can be used to enhance system performance. Then, a particular technique based on a virtual synchronous generator is presented and its effectiveness is demonstrated with simulation results.

关键词： Frequency Control Mini-Grid Energy Storage Inverter