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American Journal of Plant Sciences 2015年第2期6卷 315-322页

作者： Claudio Cardoso Marinho Cleber Palma-Silva Edélti Faria Albertoni Iara Bueno Giacomini Marcos Paulo Figueiredo Barros leonardo marques furlanetto Francisco de Assis Esteves Laboratório de Limnologia Departamento de Biologia Universidade Federal do Rio de Janeiro Rio de Janeiro Brasil Laboratório de Limnologia Instituto de Ciências Biológicas Universidade Federal do Rio Grande—FURG Rio Grande Brasil NUPEM—Universidade Federal do Rio de Janeiro Macaé Brasil

Aquatic macrophytes in shallow lakes emit high levels of methane. We hypothesize that the presence of emergent aquatic macrophytes in an artificial shallow lake promotes important input of autochthonous organic matter (OM) in sediment and higher levels of methane emission via bubbles. Samplings were performed at three sites in a small, shallow subtropical lake: (1) one station in the limnetic region and (2) - (3) two stations in the littoral region ((2) inside and (3) outside aquatic macrophyte stands). A higher concentration of OM was observed at the macrophyte station, and within this site, a higher methane concentration was observed in the sediment. These results could explain the methane ebullition values at macrophyte sites. At the macrophyte station, methane emission via bubbles contributed 17% to 56% of the total methane emission;however, at the other stations, its contribution via bubbles, was lower than 1%. This research confirmed the importance of emergent macrophytes at Polegar Lake as a source of OM in sediment and methane emission via bubbles. Further, we could confirm the positive effects of temperature on methane emission, mainly by bubbles.

关键词： Methane Emission Shallow Lakes Greenhouse Gases Global Warming

Modeling an Oil Spill along the Southern Brazilian Shelf: Forcing Characterization and Its Influence on the Oil Fate

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International Journal of Geosciences 2013年第2期4卷 397-407页

作者： Caio Eadi Stringari Wiliam Correa marques Renata Tatsch Eidt leonardo Fagundes Mello Centro de Ciência Computacionais Universidade Federal do Rio Grande Rio Grande Brazil Instituto de Matemática Estatística e Física Universidade Federal do Rio Grande Rio Grande Brazil Instituto de Oceanografia Universidade Federal do Rio Grande Rio Grande Brazil

Oil spills can generate multiple effects in different time scales on the marine ecosystem. The numerical modeling of these processes is an important tool with low computational cost which provides a powerful appliance to environmental agencies regarding the risk management. In this way, the objective of this work is to evaluate the influence of a number of physical forcing acting over a hypothetical oil spill along the Southern Brazilian Shelf. The numerical simulation was carried out using the ECOS model (Easy Coupling Oil System), an oil spill model developed at the Universidade Federal do Rio Grande—FURG, coupled with the tridimensional hydrodynamic model TELEMAC3D (EDF, France). The hydrodynamic model provides the current velocity, salinity and temperature fields used by the oil spill model to evaluate the behavior and the fate of the spilled oil. The results suggest that the local wind influence is the main forcing driven the fate of the spilled oil, and this forcing responds for more than 60% of the oil slick variability. The direction and intensity of the costal currents control between 20% and 40% of the oil variability, and the currents are important controlling the behavior and the tridimensional transportation of the oil. On the other hand, the turbulent diffusion is important for the horizontal drift of the oil. The weathering results indicate 40% of evaporation and 80% of emulsification, and the combination of these processes leads an increasing of the oil density around, 53.4 kg/m3 after 5 days of simulation.

关键词： Oil Spill Model Wind Driven Circulation Weathering

Combined Hepatocellular-Cholangiocarcinoma with Stem Cell Features—Case Report

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Case Reports in Clinical Medicine 2018年第10期7卷 526-531页

作者： leonardo Verza Carlos Henrique Rosas Gabriel marques Neves Tércia Neves Maria Dirlei Begnami Marcos Duarte Guimarã es Imaging Department A.C. Camargo Cancer Center S&atilde o Paulo Brazil Pathology Department A.C. Camargo Cancer Center S&atilde o Paulo Brazil AC Camargo Cancer Center and Universidade Federal do Vale do Sã o Francisco S&atilde o Paulo Brazil

Combined hepatocholangiocarcinoma is a rare and unique form of primary hepatic neoplasm, expressing histopathological and phenotypic aspects of hepatocellularcarcinoma and cholangiocarcinoma in the same tumor. Diagnosis may be performed by imaging, showing typical features of both components. We present a case of a 55-year-old woman presenting with abdominal pain and a hepatic mass. The patient underwent surgery and combined hepatocholangiocarcinoma with stem cells features was confirmed on pathological analysis. There are no signs of recurrence to date. Combined hepatocholangiocarcinoma requires a preoperative diagnosis, since it is a unique entity with higher rates of local and lymph node recurrence, compared to isolated forms.

关键词： Hepatocellular Carcinoma Cholangiocarcinoma Liver Neoplasm Diagnostic Imaging

Effect of Carbon Fillers in Ultrahigh Molecular Weight Polyethylene Matrix Prepared by Twin-Screw Extrusion

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Materials Sciences and Applications 2016年第12期7卷 863-880页

作者： Luiz Felipe M. Rocha Suellem B. Cordeiro leonardo C. Ferreira Flávio James H. Ramos Maria de Fátima marques Instituto de Macromoleculas Professora Eloisa Mano Universidade Federal do Rio de Janeiro RJ Cidade Universitaria Centro de Tecnologia Rio de Janeiro Brazil Instituto Militar de Engenharia (IME) Se&ccedil ã o de Engenharia Mecâ nica e Materiais Pra&ccedil a General Tibú rcio Rio de Janeiro Brazil

Oxidized (GO) and expanded (G-Exp) graphite were employed to prepare composites with ultrahigh molecular weight polyethylene (UHMWPE) matrix using masterbatches of polyethylene with different compositions. The materials and a blend of UHMWPE/HDPE were prepared by extrusion and their properties were evaluated. The effect of carbon fillers on the crystalline structure, thermo dynamic-mechanical (DMTA) and thermal properties (melting and crystallization temperatures) of the composites were discussed. The thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) measurements showed that the addition of masterbatch with GO and G-Exp significantly increased the crystallite size of composites, increasing the temperatures of melting, degradation, glass transition and the degree of crystallinity of polyethylene. DMTA analysis indicated the storage and loss moduli of composites in relation to neat UHMWPE, the blend and UHMWPE/composites. SEM micrographs showed a flatter, continuous and uniform surface meaning a compact lamellar structure. The present work resulted in interesting findings on the effects of GO on the crystalline structures, mechanical and thermal properties of UHMWPE, which can lead to generalizations useful for future work.

关键词： Polyolefin Blend Oxidized Graphite Expanded Graphite Polyethylene Composites

Laparoscopic liver resection:Experience based guidelines

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World Journal of Gastrointestinal Surgery 2016年第1期8卷 5-26页

作者： fabricio ferreira coelho jaime arthur pirola kruger gilton marques fonseca raphael leonardo cunha araújo vagner birk jeismann marcos vinícius perini renato micelli lupinacci ivan cecconello paulo herman liver surgery unit department of gastroenterologyuniversity of sao paulo medical schoolSao PauloCEP 05403-900Brazil austin health Department of SurgeryUniversity of MelbourneHeidelbergVIC 3084Australia service de chirurgie digestive viscérale et endocrinienne groupe hospitalier diaconesses-croix saint simon75020 ParisFrance

Laparoscopic liver resection(LLR) has been progressively developed along the past two decades. Despite initial skepticism, improved operative results made laparoscopic approach incorporated to surgical practice and operations increased in frequency and complexity. Evidence supporting LLR comes from case-series, comparative studies and meta-analysis. Despite lack of level 1 evidence, the body of literature is stronger and existing data confirms the safety, feasibility and benefits of laparoscopic approach when compared to open resection. Indications for LLR do not differ from those for open surgery. They include benign and malignant(both primary and metastatic) tumors and living donor liver harvesting. Currently, resection of lesions located on anterolateral segments and left lateral sectionectomy are performed systematically by laparoscopy in hepatobiliary specialized centers. Resection of lesions located on posterosuperior segments(1, 4a, 7, 8) and major liver resections were shown to be feasible but remain technically demanding procedures, which should be reserved to experienced surgeons. Hand-assisted and laparoscopy-assisted procedures appeared to increase the indications of minimally invasive liver surgery and are useful strategies applied to difficult and major resections. LLR proved to be safe for malignant lesions and offers some short-term advantages over open resection. Oncological results including resection margin status and long-term survival were not inferior to open resection. At present, surgical community expects high quality studies to base the already perceived better outcomes achieved by laparoscopy in major centers' practice. Continuous surgical training, as well as new technologies should augment the application of lap-aroscopic liver surgery. Future applicability of new technologies such as robot assistance and image-guided surgery is still under investigation.

关键词： Minimally invasive surgery Laparoscopicsurgery Hand-assisted laparoscopy Liver neoplasm Liver cirrhosis Living donor Liver Hepatectomy Livertransplantation

Endoscopic stenting for inoperable malignant biliary obstruction: A systematic review and meta-analysis

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World Journal of Gastroenterology 2015年第47期21卷 13374-13385页

作者： leonardo Zorrón Pu Eduardo Guimaraes Hourneaux de Moura Wanderley marques Bernardo Felipe Iankelevich Baracat Ernesto Quaresma Mendonca AndréKondo Gustavo Oliveira Luz Carlos Kiyoshi Furuya Júnior Everson Luiz de Almeida Artifon Gastrointestinal Endoscopy Division Department of GastroenterologyHospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo Guidelines Program Coordinator Brazilian Medical Association

AIM: To analyze through meta-analyses the benefits of two types of stents in the inoperable malignant biliary ***: A systematic review of randomized clinical trials(RCT) was conducted, with the last update on March 2015, using EMBASE, CINAHL(EBSCO), MEDLINE, LILACS/CENTRAL(BVS), SCOPUS, CAPES(Brazil), and gray literature. Information of the selected studies was extracted in sight of six outcomes: primarily regarding dysfunction, complication and reintervention rates; and secondarily costs, survival, and patency time. The data about characteristics of trial participants, inclusion and exclusion criteria and types of stents were also extracted. The bias was mainly assessed through the JADAD scale. This meta-analysis was registered in the PROSPERO database by the number CRD42014015078. The analysis of the absolute risk of the outcomes was performed using the software Rev Man, by computing risk differences(RD) of dichotomous variables and mean differences(MD) of continuous variables. Data on RD and MD for each primary outcome were calculated using the MantelHaenszel test and inconsistency was qualified and reported in χ2 and the Higgins method(I2). Sensitivity analysis was performed when heterogeneity was higher than 50%, a subsequent assay was done and other findings were compiled. Student's t-test was used for the comparison of weighted arithmetic means regarding secondary ***: Initial searching identified 3660 studies; 3539 were excluded through title, repetition, and/or abstract, while 121 studies were fully assessed and were excluded mainly because they did not compare self-expanding metal stents(SEMS) and plastic stents(PS), leading to thirteen RCT selected, with 13 articles and 1133 subjects meta-analyzed. The mean age was 69.5 years old, that were affected mostly by bile duct(proximal) and pancreatic tumors(distal). The preferred SEMS diameter used was the 10 mm(30 Fr) and the preferred PS diameter used was 10 Fr. In the metaanalysis

关键词： Biliary tract neoplasms Malignant biliaryobstruction Jaundice Palliative care Endoscopicretrograde cholangiopancreatography Stent Systematicreview Meta-analysis