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MULTIGRID METHOD FOR A MODIFIED CURVATURE DRIVEN DIFFUsION MODEL FOR IMAGE INPAINTING

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Journal of Computational Mathematics 2008年第6期26卷 856-875页

作者： carl.s brito-Loeza Department of Mathematical sciences University of Liverpool

Digital inpainting is a fundamental problem in image processing and many variational models for this problem have appeared recently in the literature. Among them are the very successfully Total Variation （TV） model [11] designed for local inpainting and its improved version for large scale inpainting： the Curvature-Driven Diffusion （CDD） model [10]. For the above two models, their associated Euler Lagrange equations are highly nonlinear partial differential equations. For the TV model there exists a relatively fast and easy to implement fixed point method, so adapting the multigrid method of [24] to here is immediate. For the CDD model however, so far only the well known but usually very slow explicit time marching method has been reported and we explain why the implementation of a fixed point method for the CDD model is not straightforward. Consequently the multigrid method as in [savage and Chen, Int. J. Comput. Math., 82 （2005）, pp. 1001-1015] will not work here. This fact represents a strong limitation to the range of applications of this model since usually fast solutions are expected. In this paper, we introduce a modification designed to enable a fixed point method to work and to preserve the features of the original CDD model. As a result, a fast and efficient multigrid method is developed for the modified model. Numerical experiments are presented to show the very good performance of the fast algorithm.

关键词： Image inpainting Variational models Regularization Multilevel methods.

Modeling of Fluidized Bed Gasification:Assessment of Zero-dimensional and CFD Approaches

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Journal of Thermal science 2015年第4期24卷 378-385页

作者： Nuno Couto Valter silva Eliseu Monteiro P.s.D.brito Abel Rouboa University of Tras-os-Montes and Alto Douro INEGI/Faculty of Engineering University of Porto C3i-Interdisciplinary Center for Research and Innovation Polytechnic Institute of PortalegreLugar da AbadessaApartado 1487301-901PortalegrePortugal MEAM Department University of Pennsylvania

In modeling fluidized bed gasification experiments,equilibrium and CFD models are valuable *** existence of multi-dimensional effects inside the reactor vessel due to the kinetics of the process and the fluid dynamics phenomena could result in deviation from the zero-dimensional *** models integrating kinetics and hydrodynamics are being developed by using a computer fluid dynamics(CFD)*** objective of this investigation is to assess and compare the adequacy of zero-dimensional and CFD approaches in modeling fluidized bed gasification regarding a semi-industrial scale(numerical results are validated under experimental runs).Results show that the zero-dimensional model based on the approach of dual stage equilibrium performs reasonably well in adequately predicting the product gas composition at different operating conditions and for different feedstocks,although with quantitative ***,the discrepancy depends on the oxygen content of the oxidation agent and on the steam-to biomass ratio decreasing when these parameters *** models provide deeper information being able to estimate the syngas composition or other operating parameter at any point of space and *** of some quantitative discrepancy,the zero-dimensional modeling approach is deemed satisfactory from the viewpoint of the determining design conditions simulation.

关键词： Gasification CFD model Dual stage equilibrium model

Diuretic window hypothesis in cirrhosis: Changing the point of view

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World Journal of Gastroenterology 2019年第26期25卷 3283-3290页

作者： Anderson brito-Azevedo Liver Transplant Unit S?o Lucas Hospital Liver Transplant Unit S?o Francisco na Providência de Deus Hospital Liver Transplant Unit Adventist Silvestre Hospital

since the 1970s,non-selective beta-blockers(NsBB)have been used to prevent variceal upper bleeding in advanced cirrhotic ***,several recent studies have raised the doubt about the benefit of NsBB in end-stage cirrhotic *** fact,they suggested a detrimental effect in these patients that even reduced *** of these studies have been assembled to compose the“window therapy hypothesis”,in which NsBB would have traditional indication to be initiated to prevent variceal upper bleeding;however,treatment should be stopped(or not be initiated)in patients with end-stage *** would reduce the cardiac reserve of these patients,worsening systemic perfusion and ***,it should be emphasized that these studies present important bias issues,and their results also suggested that diuretic treatment may also be behind the effects *** this opinion review,we changed the point of view from NsBB to diuretic treatment,based on a physiopathogenic approach of circulatory parameters of cirrhotic patients studied,and based on diuretic effect in blood pressure lowering and in other hypervolemic disease,as heart *** suggest a“diuretic window hypothesis”,composed by an open window in hypervolemic phase,an attention window when patient present in a normal plasma volume phase,and a closed window during the plasma hypovolemic phase.

关键词： Cirrhosis Non-selective beta-blockers Diuretic Window hypothesis Baveno Cardiac output

Can rainfall seasonality trigger soil water repellency in a tropical riparian forest?

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Journal of Forestry Research 2023年第3期34卷 773-780页

作者： Gleicon Queiroz de brito Johnny Rodrigues de Melo Murta sérgio Fernandes Mendonca Filho Luiz Felippe salemi Núcleo de Estudos e Pesquisas Ambientais e Limnológicas(NEPAL) Faculdade UnB de Planaltina(FUP)Universidade de Brasília(UnB)DFVila Nossa Senhora de FátimaÁrea Universitária 1Planaltina 73345-010Brazil

Though riparian areas generally have a shallow water table and higher soil moisture compared to up slope areas,climatic seasonality may trigger water repellency in tropical riparian forests,which,if persistent,could negatively affect essential ecosystem functions related to water resources protection such as reduced overland-flow,sediment transport,and nutrient *** objective of this study was to answer the following:can tropical riparian forests develop water repellency?If so,does water repellency affect infiltration on a seasonal basis?For this,water repellency and infiltration were measured in a grid of 72points during a dry and a wet month of a tropical riparian forest with a shallow water table in a region with highly marked climatic *** repellency and infiltration were significantly different between the wet and dry *** repellency affected negatively infiltration in the dry month,its effect in the wet month was *** a result,a higher infiltration capacity was observed over the wet *** research has claimed that the development and persistence of repellency in soils could promote other hydrological processes such as overland *** findings shown here demonstrate that such phenomenon does not persist longer than the dry season.

关键词： Hydrophobicity Gallery forest Aquifer recharge Climate change Erosion

shade coffee plantations maintain woody plant diversity and structure in a cloud forest landscape of southern Mexico

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Journal of Forestry Research 2021年第2期32卷 637-648页

作者： Edson AAlvarez-Alvarez R.carl.s Almazán-Nunez Fernando González-García Marlene brito-Millán Alfredo Méndez-Bahena sergio García-Ibáñez Maestría en Recursos Naturales y Ecología Facultad de Ecología MarinaUniversidad Autónoma de Guerrero39390 AcapulcoGuerreroMexico Laboratorio Integral de Fauna silvestre Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Red Biología y Conservación de Vertebrados Instituto de EcologíaA.C.CP 91073 XalapaVeracruzMexico University of California Institute for Mexico and the United states(UC MEXUs) Cuerpo Académico Biodiversidad y Gestión Ambiental SustentableFacultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Laboratorio de Biología de la Conservación Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de Guerrero39090 Chilpancingo de los BravoGuerreroMexico Laboratorio de Ecología Cuantitativa Facultad de Ecología MarinaUniversidad Autónoma de Guerrero39390 AcapulcoGuerreroMexico

Cloud forest ecosystems of the Latin American tropics are highly threatened by changes in land-use such as expanding croplands and livestock pastures that promote shifts in the structure and composition of plant communities in these ***,shade coffee plantations represent a forest management alternative that has been shown to maintain biodiversity in these *** this study,we evaluated changes in the composition,diversity,and structure of Mexican cloud-forest woody species for three land use categories:cattle pastures,shade coffee plantations and advanced succession *** each category,fifteen 0.28-ha plots were established and the composition and diversity of vegetation was *** of species was analyzed using ordination methods,and alpha diversity was compared using Hill ***-seven woody species belonging to 40 families were *** richness and diversity was high in both the advanced successional forest and coffee plantations compared to cattle *** composition and structure was similar between late succession forests and coffee plantations with both land uses also being more structurally complex than cattle *** results show how shade coffee cultivation is a land-use activity that maintains woody plant communities in a manner that aligns with biodiversity conservation.

关键词： Land uses Late succession Plant diversity shade coffee Vegetation structure

Fluidized and vibrofluidized shallow beds of fresh leaves

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Particuology 2011年第2期9卷 139-147页

作者： Renata de Aquino brito Lima Maria do Carmo Ferreira Drying Center of Pastes Suspensions and SeedsChemical Engineering DepartmentFederal University of S o Carlos

The fluid dynamics behavior of shallow fluidized and vibrofluidized beds operating with fresh leaves was investigated with the aim of exploring drying applications in a modified conveyor belt （MCB） system, which may be operated in a fixed- or fluidized-bed mode. Leaves of the specimens Duranta repens, schinus molle, Coleus barbatus, Buxus sempervirens, and Bougainvillea spectabilis were tested with a range of sphericities from 0.063 to 0.213, bulk densities from 0.038 to 0.251 g/cm3, apparent densities from 0.52 to 0.97 g/cm3 and ratios of total surface area to volume from 21 to 224 cm-1. Fluidization characteristic curves were obtained by measuring pressure drops versus air velocity in a rectangular column of 0.20 m - 0.11 m cross section. It was not possible to reach real fluidized regimes with the leaves due to strongly non-homogeneous beds. Nevertheless, the characteristic curves allowed for the identification of a transition regime from fixed- to expanded-beds, and parameters such as air velocity and pressure drop obtained from the experimental data at the transition were reproducible for specimens with lower surface area or lower specific gravity （i.e., Duranta repens, schinus molle, and Bougainvillea spectabilis）. The transition velocity and pressure drop could not be predicted by the literature developed for estimat- ing minimum fluidization conditions. The use of vibration at dimensionless vibration parameters （Γ） of 0.5 and 1.0 helped to reduce channeling and decrease the transition velocities from fixed to expanded regimes although it did not affect the pressure drops after the bed expansion. The results suggest that drying fresh leaves using the MCB dryer operating in a fluidized mode would not be feasible because none of the materials investigated attained a high-quality fluidization. Operation of the MCB dryer may be pos- sible by alternating between the fixed and vibrofluidized modes. For the specimens tested, the drying should be performed in a range

关键词： LeavesLow-sphericity particlesPressure dropsFluidizationVibration

Clinical/Behavioral Monitoring of Rodents and Rabbits Undergoing scientific Experiments

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Open Journal of Veterinary Medicine 2024年第5期14卷 91-109页

作者： Luiz Cesar Cavalcanti Pereira Jhônata Willy Rocha Coelho Hyago da silva Medeiros Elidio Rita de Cássia dos Passos Ferraz Da silva João Gabriel Regis sobral Bárbara Alves de brito soledade Leandro Thomaz Vilela Isabele Barbieri Dos santos Institute of science and Technology in Biomodels (ICTB) Oswaldo Cruz Foundation (FIOCRUZ) Rio de Janeiro Brazil Laboratory Animal Facility of the carl.s Chagas Pavilion of the Animal Experimentation Center (CEA) Oswaldo Cruz Institute (IOC) Oswaldo Cruz Foundation (FIOCRUZ) Rio de Janeiro Brazil

Background: We currently have international and national guidelines regarding the assessment and monitoring of clinical signs and humane endpoints in animals used in teaching and research, which make the performance of these activities mandatory for any experiment and professional working in this area. Assigning the severity of a research experiment is the result of an analysis of records of observations of the animal’s behavior, and clinical signs. The aim of this study was to describe the importance of carrying out a severity assessment associated with clinical and behavioral monitoring of rodents and rabbits during experimentation to maintain the welfare of these animals undergoing scientific research. Methods: The literature search was carried out using the following terms: “Monitoring”;“Humane endpoints”;“Animal welfare”, “Rodents”;“Rabbits”, and as connectors “and”;“or”, in the following databases: PubMed;LILACs/BIREME and sciELO. Results: A total of 987 articles were identified in the databases, and 20 of these studies were included in this review. Conclusions: Humane endpoint protocols and procedure severity tables are of the utmost importance, both from an ethical point and to refine the results of research conducted on laboratory animals. They should be drawn up jointly by the teams responsible for the project and the maintenance of the animals during the research period, and the data obtained should be published so that the scientific community can have access to it, helping to disseminate these practices, as well as helping to draw up new procedures. Monitoring and evaluating the welfare and clinical condition of animals undergoing scientific research procedures is the responsibility of the professors, researchers, veterinarians, and animal facility coordinators. The Ethics Committee on the Use of Animals must monitor all the activities conducted with the animals, by inspecting the experimental procedures and the physical environment of the laboratory an

关键词： Monitoring Humane Endpoints Animal Welfare Experimental Design Laboratory Animals’ Investigations

stereotactic radiosurgery for haemorrhagic cerebral cavernous malformation:a multi-institutional,retrospective study

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stroke & Vascular Neurology 2024年第3期9卷 221-229,I0130,I0131页

作者： Chloe Dumot Georgios Mantziaris sam Dayawansa Zhiyuan Xu stylianos Pikis selcuk Peker Yavuz samanci Gokce D Ardor Ahmed M Nabeel Wael A Reda sameh R Tawadros Khaled Abdelkarim Amr M N El-shehaby Reem M Emad Eldin Ahmed H Elazzazi Nuria Martínez Moreno Roberto MartínezÁlvarez Roman Liscak Jaromir May David Mathieu Jean-Nicolas Tourigny Manjul Tripathi Akshay Rajput Narendra Kumar Rupinder Kaur Piero Picozzi Andrea Franzini Herwin speckter Wenceslao hernandez Anderson brito Ronald E Warnick Juan Alzate Douglas Kondziolka Greg N Bowden samir Patel Jason sheehan Department of Neurological surgery Hospices Civils de LyonLyonFrance Department of Neurological surgery University of VirginiaCharlottesvilleVirginiaUSA Department of Neurosurgery Koc University School of MedicineIstanbulTurkey Gamma-knife Center Nasser institute HospitalCairoEgypt Neurosurgery Department Benha UniversityBenhaEgypt Departments of Neurosurgery Ain Shams UniversityCairoEgypt Department of Clinical Oncology Ain Shams UniversityCairoEgypt Department of Radiation Oncology National Cancer InstituteCairo UniversityGizaEgypt Faculty of Medicine Extended Modular ProgramAin Shams UniversityCairoEgypt Department of Radiosurgery Rúber Internacional HospitalMadridSpain Department of stereotactic and Radiation Neurosurgery Na Homolce HospitalPragueCzech Republic Neurosurgery Centre de recherche du CHUSUniversitéde SherbrookeSherbrookeQuebecCanada Neurosurgery PGIMERChandigarhChandigarhIndia Radiation Therapy PGIMERChandigarhChandigarhIndia Neurosurgery IRCCS Istituto Clinico HumanitasRozzanoMilanItaly Dominican Gamma Knife Center and Radiology Department CEDIMATSanto DomingoDominican Republic Gamma Knife Center Mayfield ClinicThe Jewish Hospital-Mercy HealthCincinnatiOhioUSA Neurosurgery NYU Langone HealthNew YorkNew YorkUSA Neurosurgery University of AlbertaEdmontonAlbertaCanada Division of Radiation Oncology Department of OncologyUniversity of AlbertaEdmontonAlbertaCanada

Background Cerebral cavernous malformations(CCMs)frequently manifest with *** radiosurgery(sRs)has been employed for CCM not suitable for *** effect on reducing haemorrhage risk is still *** aim of this study was to expand on the safety and efficacy of sRs for haemorrhagic *** This retrospective multicentric study included CCM with at least one haemorrhage treated with single-session *** annual haemorrhagic rate(AHR)was calculated before and after *** event analysis and Cox regression were used to evaluate factors associated with *** radiation effects(AREs)and occurrence of new neurological deficits were *** The study included 381 patients (median age:37.5 years(Q1–Q3:25.8–51.9))with 414 *** AHR from diagnosis to sRs excluding the first haemorrhage was 11.08 per 100 CCM-years and was reduced to 2.7 per 100 CCM-years after *** recurrent event analysis,sRs,HR 0.27(95%CI 0.17 to 0.44),ps associated with a decreased risk of haemorrhage,and the presence of developmental venous anomaly(DVA)with an increased risk,HR 1.60(95%CI 1.07 to 2.40),p=*** cumulative risk of first haemorrhage after sRs was 9.4%(95%CI 6%to 12.6%)at 5 years and 15.6%(95%CI%9 to 21.8%)at 10 *** doses>13 Gy,HR 2.27(95%CI 1.20 to 4.32),p=0.012 and the presence of DVA,HR 2.08(95%CI 1.00 to 4.31),p=0.049 were factors associated with higher probability of post-sRs ***-sRs haemorrhage was symptomatic in 22 out of 381(5.8%)patients,presenting with transient(15/381)or permanent(7/381)neurological *** occurred in 11.1%(46/414)CCM and was responsible for transient neurological deficit in 3.9%(15/381)of the patients and permanent deficit in 1.1%(4/381)of the *** doses>13 Gy and CCM volume>0.7 cc were associated with increased risk of ARE.

关键词： doses haemorrhagic diagnosis

Emulsion-filled gels of soy protein isolate for vehiculation of vitamin D3:Effect of protein solubility on their mechanical and rheological characteristics

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Food Bioscience 2022年第1期45卷 75-87页

作者： Letícia s.Ferreira Thais C.brito-Oliveira samantha C.Pinho Laboratory of Encapsulation and Functional Foods Department of Food EngineeringSchool of Animal Science and Food Engineering(FZEA)University of S˜ao Paulo(USP)Av.Duque de Caxias Norte 225–Jd ElitePirassunungaSP13635-900Brazil

The aim of this study was to develop heat-induced gels of soy protein isolate(sPI)filled with Brazil nut oil emulsions encapsulating vitamin D3(VD3).Before gelation,dispersions produced with different sPI concentrations(11-15%,w/w)were subjected to different pretreatments(manual mixing or mechanical stirring at 800 rpm for 10,20,and 30 min)and had their protein solubility *** application of mechanical stirring increased the solubility of proteins and decreased the average particle size,affecting the microstructure(observed by confocal laser scanning microscopy)and rheological properties(evaluated by uniaxial compression and small strain oscillatory tests)of the heat-set *** incorporation of emulsions(produced with Brazilian nut oil)into gels formed emulsion filled gels(EFGs),which presented higher Young’s moduli andσH in comparison to non-filled gels(NFGs),indicating that the oil droplets were active within the *** properties of EFGs subjected to small strain oscillatory tests,varied with the pretreatment conditions and sPI concentrations,highlighting the high influence of protein solubility,matrix inhomogeneities,and droplet clustering for determining the properties of such complex ***,the heat-induced emulsion-filled gels of sPI produced were effective in protecting VD3,presenting good retention after 30 days of storage under refrigeration,and represent promising alternative for the production of future food gelled products.

关键词： Emulsion-filled gels soy protein isolate Cholecalciferol Gel structure