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Spectral Properties and Optimality for Elementary Matrices

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Journal of the Operations Research Society of China 2018年第3期6卷 467-472页

作者： Ricardo Biloti João Daniel Palma ramos Jin-Yun Yuan Department of Applied Mathematics University of Campinas&INCT-GPCampinas 13083-859Brazil Instituto Kumon de Educação Ltda. São Paulo 04006-002Brazil Department of Mathematics Federal University of ParanáCuritiba 81531-980Brazil

A generalization of the Householder transformation,renamed as elementary matrix by ***:Unitary transformation of a nonsymmetric matrix,***,5(4),339–342,1958,was introduced by LaBudde(Math Comput 17(84):433–437,1963)as a tool to obtain a tridiagonal matrix similar to a given square *** of the free parameters of the transformation can be chosen to attain better numerical *** this work,we study the spectral properties of the *** also propose a special choice for free coefficients of that transformation to minimize its condition *** transformation with such suitable choice of parameters is called optimal.

关键词： Symmetric and triangular(ST)decomposition Non-symmetric system Elementary matrix Householder transformation

Outflow reconstruction with arterial patch in domino liver transplantation: a new technical option

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Hepatobiliary & Pancreatic Diseases International 2014年第5期13卷 551-554页

作者： Laura Lladó Emilio ramos Sofia De LaSerna Joan Fabregat Liver Transplant Unit Hospital Universitari de Bellvitge

Domino liver transplantation（LT）, using livers from familial amyloidotic polyneuropathy（FAP） patients, is a well described technique useful to expand donor pool. One of the main difficulties of this type of LT arises from the necessity to share the vascular pedicles between the graft and the donor. The most important challenge resides in restoring a proper hepatic venous outflow in the FAP-liver *** is specially challenging when using the piggy-back technique, because the hepatic stumps may be too short. To overcome this issue, surgeons explored several techniques using different types of venous grafts. We describe a new technical option by using an arterial graft from the deceased donor. By using both iliac arteries a long graft is created and sutured as needed to the hepatic vein stump. We describe herein this new technique employed in a domino liver recipient who underwent retransplantation for ischemic cholangitis. The procedure was performed using the piggy-back technique; the venous stump of the FAP liver was reconstructed with the arterial graft. The patient had uneventful postoperative and mid-term hepatic function, and anastomosis was patent 24 months after LT.

关键词： liver transplantation technique graft hepatic vein iliac artery

Feral Cats: Parasitic Reservoirs in Our Zoos?

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Open Journal of Veterinary Medicine 2020年第8期10卷 126-138页

作者： Thalyta Ananias Lima Paula Andrea Borges Salgado Carolina Romeiro Fernandes Chagas Patrícia Locosque ramos Edson Aparecido Adriano Irys Hany Lima Gonzalez Department of Biological Science S&#227 o Paulo Federal University (UNIFESP) Diadema Brazil Applied Research Department S&#227 o Paulo Zoological Park Foundation S&#227 o Paulo Brazil

Up until the recent past, zoos served limited function, primarily existing for entertainment value. Today’s zoos, however, are serving many roles, chief among them: species conservation of captive animals. The biggest zoo in Brazil, S?o Paulo Zoological Park Foundation, has among its 2000 animals and many species of wild cats. The presence of domestic cats living freely in zoos is common and can be a source of spreading disease. The aim of this study was to verify the variety and prevalence of parasites found in the feces of felids (feral and wild) living in the S?o Paulo Zoo. The results of this parasitological analysis have been obtained from the laboratory of clinical analysis and correspond to the 4-year period beginning January/2009 and ending December/2012. Eight species of parasites were identified in the feces of captive wild cats and three in the feces of feral cats. For those captives, Toxocara cati (7.95%) had the highest prevalence, followed by Toxascaris leonina (7.58%), Isospora sp. (2.03%), Hymenolepis nana (0.92%), Eimeria sp., Giardia sp. and Blastocystis sp. (0.37% each) and Ascaris sp. (0.18%). Among the feral cats, we found Toxocara cati (59.26%), Giardia sp. (22.22%) and Isospora sp. (11.11%). For the captive group, we also distinguished natives from exotic species, finding native species to be more frequently parasitized than the exotic ones. Key to our findings, though, was the fact that a few parasite species were found among all groups of felids, specifically (Toxocara cati, Giardia sp. and Isospora sp). Further research is needed, however,

关键词： Enteroparasites Felids Felis catus Toxocara cati Wild Animals

Growth and Production of Hydroponic Pepper under Salt Stress and Plant Density

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American Journal of Plant Sciences 2017年第9期8卷 2255-2267页

作者： Guilherme De Freitas Furtado Antonio ramos Cavalcante Lúcia Helena G. Chaves José Amilton Santos Júnior Hans Raj Gheyi Department of Agricultural Engineering Federal University of Campina Grande Campina Grande Brazil Department of Agricultural Engineering Federal Rural University of Pernambuco Recife Brazil Postgraduate Program in Agricultural Engineering Federal University of Rec&#244 ncavo da Bahia Cruz das Almas Brazil

The viability of the use of brackish water in the hydroponic cultivation of vegetables cannot dispense with auxiliary techniques such as water mixing and the use of plant densities. In this sense, the objective of the present work was to analyze the growth and production of sweet pepper, cv. All Big, under hydroponic conditions, under different levels of electrical conductivity of the nutrient solution (1.7, 3.7, 5.7, 7.7, 9.7 and 11.7 dS·m-1) in plants spaced every 0.2 m and 0.3 m. These treatments were distributed in a completely randomized experimental design, analyzed in a 6 × 2 factorial scheme, with five replications. The growth variables were evaluated at 60, 75 and 90 days after sowing and the production variables at the time of harvest;however, the results were submitted to analysis of variance, at a 0.05 probability level. The interaction between the electrical conductivity of the nutrient solution and the density of plants influenced the behavior of the growth and production variables of pepper (All Big). It was verified that the pepper plants had better performance of the biometric variables plant height, stem diameter and number of leaves when cultivated every 30 cm. At the time, in the analysis by plant, the production of pepper fruits was more expressive when spacing of 30 cm was adopted, however, in the tube of six meters, when 20 cm of spacing was used, the number of fruits was on average, 26.38% and 16.40% higher than lower density, in the electrical conductivities 1.7 and 11.7 dS·m-1.

关键词： Capsicum annuum L. Brackish Water Rainwater

Performance of a Double Catalyst Fuel Cell Cathode with a Tubular Oxygen Breathing and Preliminary Reduction Zone

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Journal of Thermal Science 2005年第2期14卷 187-192页

作者： Luís A.Waack BAMBACE Miriam NISHIMORI Fernando M.ramos Demétrio BASTOS-NETTO Instituto Nacional de Pesquisas Espaciais-INPE Av.Dos Astronautas 1758 S■o José dos CamposSPBrazilCEP 12210-970Instituto Nacional de Pesquisas Espaciais-INPE Av.Dos Astronautas 1758S■o José dos CamposSPBrazilCEP 12210-970Instituto Nacional de Pesquisas Espaciais-INPE Av.Dos Astronautas 1758S■o José dos CamposSPBrazilCEP 12210-970Instituto National de Pesquisas Espaciais-INPE Rod.Presidente Dutra km 40Cachoeira PaulistaSPBrazil CEP12630-000

This paper discusses a mathematical model for a liquid phase reacting flow occurring at the cathode of a patent pending novel fuel cell geometry, where a non homogeneous catalysis carried by gold and Prussian Blue, with the first reducing air O2 and the second the resulting H2O2. The breathing zone is porous walls microtubes, with three different types of pores in its walls. Inside the microtuhes there is water solution of sulfuric acid. The microtubes possess an external layer of extremely porous polymer hydrophobic agent. A Prussian Blue thin porous layer is over the selective membrane. Appropriate porous and tubular connecting elements close the fluid loop. The asymmetry induces proper current and electric potential profiles, which leads to a mainly electrocapillary electrokinetic flow, which enhances the oxygen transport and assures the H2O2 flow to its reduction layer.

关键词：非同源催化燃料电池通气区域动电传送数学模型

From a sequential pattern,temporal adjustments emerge in hummingbird traplining

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Integrative Zoology 2019年第2期14卷 182-192页

作者： Maria C.TELLO-ramos Andrew T.HURLY Susan D.HEALY School of Biology University of St AndrewsScotlandUK Department of Biological Sciences University of LethbridgeAlbertaCanada

Animals that feed from resources that are constant in space and that refill may benefit from repeating the order in which they visit *** is a behavior known as traplining,a spatial ***,like other central-place foragers,use short traplines when moving between several rewarding *** we investigated whether traplining hummingbirds also use relevant temporal information when choosing which flowers to *** rufous hummingbirds that were allowed to visit 3 artificial flower patches in which flowers were refilled 20 min after they had been depleted repeated the order in which they visited the 3 *** they tended to visit the first 2 patches sooner than 20 min,they visited the third patch at approximately 20-min inter*** time between visits to the patches increased across the experiment,suggesting that the birds learned to wait longer before visiting a *** birds appeared to couple the sequential pattern of a trapline with temporal regularity,to some *** suggests that there is a temporal component to the repeated spatial movements flown by foraging wild hummingbirds.

关键词： foraging patterns interval timing rufous hummingbirds Selasphorus rufus

Stretching the spectra of Kerr frequency combs with self-adaptive boundary silicon waveguides

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Advanced Photonics 2020年第4期2卷 29-38页

作者： Jianhao Zhang Vincent Pelgrin Carlos Alonso-ramos Laurent Vivien Sailing He Eric Cassan UniversitéParis-Saclay CNRSCentre de Nanosciences et de NanotechnologiesPalaiseauFrance Zhejiang University Centre for Optical and Electromagnetic ResearchState Key Laboratory for Modern Optical InstrumentationHangzhouChina

Dispersion engineering of optical waveguides is among the most important steps in enabling the realization of Kerr optical frequency combs.A recurring problem is the limited bandwidth in which the nonlinear phase matching condition is satisfied,due to the dispersion of the *** limitation is particularly stringent in high-index-contrast technologies such as *** propose a general approach to stretch the bandwidth of Kerr frequency combs based on subwavelength engineering of single-mode waveguides with self-adaptive *** wideband flattened dispersion operation comes from the particular property of the waveguide optical mode that automatically self-adapts its spatial profile at different wavelengths to slightly different effective spatial spans determined by its effective index *** flattened dispersion relies on the squeezing of small normal-dispersion regions between two anomalous spectral zones,which enables it to achieve two Cherenkov radiation points and substantially broaden the comb,achieving a bandwidth between 2.2 and 3.4μm *** strategy opens up a design space for trimming the spectra of Kerr frequency combs using high-index-contrast platforms and can provide benefits to various nonlinear applications in which the manipulation of energy spacing and phase matching are pivotal.

关键词： nonlinear optics effective boundary subwavelength grating silicon frequency comb

Evaluation of Cinnamon by Solid-State NMR Employing Relaxometry

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Materials Sciences and Applications 2023年第3期14卷 142-147页

作者： Pedro Paulo Merat Roberto Cucinelli Neto Vitor Santos ramos Maria Inês Bruno Tavares Instituto de Macromoléculas Professora Eloisa Mano (IMA) da Universidade Federal do Rio de Janeiro UFRJ Centro de Tecnologia Ilha do Fund&atildeo Rio de Janeiro Brasil IFRJ Avenida República do Paraguai Duque de Caxias Brasil

To evaluate the molecular dynamics and the molecular regions presented in the cinnamon types it was chosen to evaluate them without any treatment, and for that it was used low-field nuclear magnetic resonance (NMR) through the pulse sequence such as MSE-FID, an NMR sequence in the time domain, and from the longitudinal relaxation time (with a time constant T1), employing the inversion-recovery pulse sequence. The low-field NMR results indicate that the techniques chosen were a very good alternative to evaluate these types of samples food and their structural organization according to their constituents. The molecular mobility is different.

关键词： Cinnamon Low-Field NMR NMR Relaxation Functional Food

Fiber Optic Intensity-Modulated Sensors： a Review in Biomechanics

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Photonic Sensors 2012年第4期2卷 315-330页

作者： Paulo RORIZ Antonio ramos Jose L. SANTOS Jose A. SIMOES Department of Mechanics University of Aveiro 3810-193 Aveiro Portugal Faculty of Sciences University of Porto Rua do Campo Alegre 687 4150-179 Porto Portugal

纤维眼的传感器有在 biomechanics 使他们很漂亮的一套性质。然而，他们对许多仍然保持未知在这块地里工作。一些可能的原因是少见的信息，很少在一个平淡的基础用他们研究组，并且弄平提供全承包、买得起的答案的更少公司。不过，当光... 详细信息

纤维眼的传感器有在 biomechanics 使他们很漂亮的一套性质。然而，他们对许多仍然保持未知在这块地里工作。一些可能的原因是少见的信息，很少在一个平淡的基础用他们研究组，并且弄平提供全承包、买得起的答案的更少公司。不过，当光纤维革命化在电信带数据的方法，一个类似的趋势在察觉到的世界上是可检测的。现在的评论试图描述纤维自从他们的介绍，在 biomechanics 察觉到的最相关的贡献，从 1960 年代到礼品，集中于基于紧张的配置。一个努力被作了识别关键研究人员，研究和开发(R&D ) 组和主要应用程序。

关键词：光纤传感生物力学强度调制传感器评论数据通讯研究人员吸引力