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The Lid-Driven Square Cavity Flow: From Stationary to Time Periodic and Chaotic

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Communications in Computational Physics 2007年第5期2卷 900-932页

作者： salvador Garcia Departamento de Ciencias Matem´aticas y F´ısicas Universidad Cat´olica de TemucoCasilla 15-D TemucoChile

Ranging from Re=100 to Re=20,000,several computational experiments are conducted,Re being the Reynolds number.The primary vortex stays put,and the longterm dynamic behavior of the small vortices determines the nature of the solutions.For low Reynolds numbers,the solution is stationary;for moderate Reynolds numbers,it is time periodic.For high Reynolds numbers,the solution is neither stationary nor time periodic:the solution becomes chaotic.Of the small vortices,the merging and the splitting,the appearance and the disappearance,and,sometime,the dragging away from one corner to another and the impeding of the merging—these mark the route to chaos.For high Reynolds numbers,over weak fundamental frequencies appears a very low frequency dominating the spectra—this very low frequency being weaker than clear-cut fundamental frequencies seems an indication that the global attractor has been attained.The global attractor seems reached for Reynolds numbers up to Re=15,000.This is the lid-driven square cavity flow;the motivations for studying this flow are recalled in the Introduction.

关键词： Finite differences staggered marker-and-cell(MAC)mesh incremental unknowns generalized Stokes equations incompressible Navier-Stokes equations chaos.

Benign Gynecomastia with Abscess

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Open Journal of Radiology 2023年第4期13卷 256-261页

作者： Arit Ntekim Magdalena salvador Rutgers New Jersey Medical School Newark NJ USA Department of Radiology University Hospital of New Jersey Medical School Newark NJ USA

Gynecomastia is a common finding in male patients, however, abscess is a rare finding in male patients. Typical management for benign gynecomastia is to continued surveillance and no additional annual imaging is required [1]. Breast abscess in male is managed with incision and drainage and antibiotics [2], however, the management of gynecomastia superimposed with recurrent ab-scess does not have clear management and should be managed on an indi-vidual basis. We present a case of a 44-year-old man who with a recurrent left breast abscess in addition to persistent gynecomastia. The abscess was drained and cultured. The culture grew Citrobacter koseri(diversus) and patient was placed on Bactrim DS for 7 days and was referred to the breast clinic for fur-ther evaluation. This study aims to elucidate and review the literature to iden-tify similar cases and potential management of male patients with recurrent abscess and gynecomastia.

关键词： Gynecomastia Subareolar Abscess

Saturation-excess overland flow in the European loess belt:An underestimated process?

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International Soil and Water Conservation Research 2023年第4期11卷 688-699页

作者： Valentin Landemaine Olivier Cerdan Thomas Grangeon Rosalie Vandromme Benoit Laignel Olivier Evrard Sébastien salvador-Blanes J.Patrick Laceby BRGM F-45060OrléansFrance University of Rouen M2CRouenFrance Laboratoire des Sciences du Climat et de l'Environnement(LSCE/IPSL) UnitéMixte de Recherche 8212(CEA/CNRS/UVSQ)UniversitéParis-SaclayGif-sur-YvetteFrance University of Tours UR 6293-GéoHydrosystèmes Continentaux(GEHCO)France Alberta Environment and Protected Areas CalgaryCanada

A major challenge in runoff and soil erosion modelling is the adequate representation of the most relevant processes in models while avoiding over parameterization.In the European loess belt,pro-gressive soil crusting during rainfall events,resulting in infiltration-excess runoff,is usually considered the dominant process generating runoff on catchments covered with silty soils.Saturation-excess may also occur and affect their runoff and erosion behavior.However,saturation-excess runoff occurrence and quantification have rarely been performed and is usually not taken into account when modelling runoff and erosion in these environments.Accordingly,a continuous simulation of the Austreberthe catchment(214 km^(2)),located in the European loess belt(Normandy,France),was conducted with the new Water and Sediment(WaterSed)model over 12 years,corresponding to more than 780 individual rainfall events,at a 25 m spatial resolution.The inter-annual variability of runoff and erosion was closely linked to the number of intense events per year and their distribution through the year.The model was properly calibrated over a representative set of 35 rainfall events,considering either infiltration-excess and/or saturation-excess runoff.It was also able to reproduce the measured runoff volume for most of the monitoring period.However,the three years with most rainfall were adequately modelled only including saturation-excess runoff.An analysis performed at the seasonal scale revealed that saturation was modelled in the catchment during almost all of the modelling period,suggesting the importance of this often overlooked process in current modelling attempts.

关键词： European loess belt Soil erosion Saturation-excess runoff WaterSed model

A stable Cenozoic geologic time scale is indispensable

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Episodes 2006年第1期29卷 43-45页

作者： Amos salvador Department of Geological Sciences University of Texas at Austin Austin Texas 78712 USA.

A stable, standard geologic time scale is indispensable for the clear and precise communication among geologists; it is a basic tool of geologic work. Considerable progress has been made to achieve such a stable time scale. However, during the last few years several proposals have been made to modify the Cenozoic section of the geologic time scale that threaten to destabilize it. Seven articles published in Episodes since 2000 that could contribute to this destabilization are discussed. They provide excellent examples of the profusion of different terminologies, hierarchies, and stratigraphic relationships that have been proposed: to eliminate the Tertiary and the Quaternary or to raise their rank to suberathems; to extend the Neogene to the present; to make the Quaternary a formal subsystem of the Neogene, or consider it an informal stratigraphic unit; to eliminate the Holocene, and to decouple the base of the Pleistocene from the base of the Quaternary. If adopted, these proposals would cause nothing but great confusion and controversy. They disregard the clear preferences of geologists the world over as reflected by the terminology they have been using for many decades. Common sense would dictate the continued use of this terminology in its current, widely accepted form.

关键词：新生代地质时间比例尺地质工作

Soot formation and oxidation during bio-oil gasification:experiments and modeling

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Journal of Energy Chemistry 2013年第5期22卷 701-709页

作者： Younes Chhiti Marine Peyrot Sylvain salvador LEGI UJF-Grenoble 1/Grenoble-INP/CNRSBP 53Grenoble F-38041 France CEA/DRT/LITEN/DTBH/LTB Laboratoire des Technologies pour la Biomasse 17 rue de Martyrs 38054Grenoble France Ecole des Mines d'Albi-Carmaux Centre RAPSODEE FRE CNRS 3213 Campus Jarlardroute de Teillet 81013Albi France

A model is proposed to describe soot formation and oxidation during bio-oil gasification.It is based on the description of bio-oil heating,devolatilization,reforming of gases and conversion of both char and soot solids.Detailed chemistry (159 species and 773 reactions) is used in the gas phase.Soot production is described by a single reaction based on C2H2species concentration and three heterogeneous soot oxidation reactions.To support the validation of the model,three sets of experiments were carried out in a lab-scale Entrained Flow Reactor (EFR) equipped with soot quantification device.The temperature was varied from 1000 to 1400 C and three gaseous atmospheres were considered:default of steam,large excess of steam(H2O/C=8),and the presence of oxygen in the O/C range of 0.075–0.5.The model is shown to accurately describe the evolution of the concentration of the main gas species and to satisfactorily describe the soot concentration under the three atmospheres using a single set of identified kinetic parameters.Thanks to this model the contribution of different mechanisms involved in soot formation and oxidation in various situations can be assessed.

关键词： soot gasification pyrolysis partial oxidation bio-oil

Inducing α-synuclein compaction: a new strategy for inhibiting α-synuclein aggregation?

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Neural Regeneration Research 2019年第11期14卷 1897-1898页

作者： Francisca Pinheiro salvador Ventura Institut de Biotecnologia i Biomedicina Universitat Autonoma de BarcelonaBellaterraSpainDepartament de Bioquimica i Biologia MolecularUniversitat Autonoma de BarcelonaBellaterraSpain

Proteins might misfold during translation and folding or even once they are in their native states, due to stochastic fluctuations, destabilizing mutations or cellular stress. Aberrant protein species are usually detected and either refolded or cleared by the protein quality control machinery (Ciechanover and Kwon, 2015). When misfolded protein conformers cannot be degraded, they tend to self-assemble to form aggregates, a characteristic of many neurodegenerative diseases.

关键词： inhibitingα-synuclein aggregation native states protein quality control machinery

The 3x + 1 Conjecture, a Direct Path

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American Journal of Computational Mathematics 2023年第2期13卷 350-355页

作者： salvador Bermúdez Gómez Instituto Politécnico Nacional SEPI-ESIME-Zacatenco Mexico City México

The 3x + 1 problem, is a math problem that has baffled mathematicians for over 50 years. It’s easy to explain: take any positive number, if it’s even, divide it by 2;if it’s odd, multiply it by 3 and add 1. Repeat this process with the resulting number, and the conjecture says that you will eventually reach 1. Despite testing all starting values up to an enormous number, no one has proved the conjecture is true for all possible starting values. The problem’s importance lies in its simplicity and difficulty, inspiring new ideas in mathematics and advancing fields like number theory, dynamical systems, and computer science. Proving or disproving the conjecture would revolutionize our understanding of math. The presence of infinite sequences is a matter of question. To investigate and solve this conjecture, we are utilizing a novel approach involving the fields of number theory and computer science.

关键词： 3x + 1 Collatz Solved Computer Science Number Theory New Algo-rithm

Mine tailings storage dams modify upstream headwater fish assemblages

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Water Biology and Security 2023年第2期2卷 32-42页

作者： Gilberto N.salvador Robert M.Hughes Fabio Vieira Raphael Ligeiro Luciano F.A.Montag Ecology and Conservation Laboratory(LABECO) Federal University of ParaBiological Sciences InstituteRua Augusto Correa01GuamaCaixaBelemPA479Brazil Fish Ecology and Conservation Laboratory(Eco-Peixes) Federal University of Minas GeraisBiological Sciences InstituteAv.Antonio Carlos6627Belo HorizonteMGCEP:31.270-901Brazil Amnis Opes Institute 2895 SE GlennCorvallisOR97333USA Department of Fisheries Wildlife&Conservation SciencesOregon State UniversityCorvallisOR97331USA Zoology Department Federal University of Minas GeraisBiological Sciences InstituteAv.Antonio Carlos6627CEP:31.270-901Belo HorizonteMGBrazil

Riverscape connectivity is a critically important component determining the ecological condition of lotic ecosystems.We evaluated changes in fish assemblages caused by the loss of connectivity by mine tailings storage dams(TSDs),hypothesizing that headwater fish assemblages are restructured by TSDs located downstream,even though the upstream habitats are not altered.We used standard methods to collect fish in 24 first to third order sites,with half draining to TSDs(dammed)and the other half free from this impact(undammed).To identify differences between treatments,we used PERMANOVA to test both environmental variables and ichthyofauna composition(Bray-Curtis similarity index)and evaluated the biological metrics that most influenced assemblage composition change.As expected,we observed no difference between treatments for environmental variables,but we did observe differences in fish assemblage composition.We also observed five metrics with lower values in dammed streams(richness and abundance of intolerant species,siluriform richness,and abundance of Pareiorhaphis cf.proskynita and Trichomycterus brasiliensis)and two metrics with higher values in dammed streams(perciform richness and abundance of Oligosarcus argenteus).We believe these changes resulted from of stream fragmentation by TSDs,in addition to source-sink mechanisms and conclude that mine TSDs located downstream change headwater fish assemblages,an impact often neglected in biomonitoring and bioassessment studies.

关键词： Habitat fragmentation Source-sink dynamics Iron ore mining Rio Doce basin

Meso-American Nephropathy in El salvador: Increasing Farmer Participation in MeN Prevention Efforts

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Occupational Diseases and Environmental Medicine 2019年第2期7卷 50-63页

作者： Keven Bermudez Carlos Orantes Montserrat León Marta jiménez Nicole Vidal Pol De Vos Institute for Global Health and Development Queen Margaret University Edinburgh UK National Health Institute Ministry of Health (MINSAL) of San Salvador San Salvador El Salvador

Objectives: This paper highlights and discusses major factors affecting salvadoran farmers’ involvement in National Health System-led efforts to prevent MeN in El salvador and includes some recommendations to enhance their involvement. Methods: The study, conducted in El salvador in June 2018, involved 10 life-long farmers residing in five MeN-affected communities in Chalatenango and Usulutan Departments who were either MeN-free or MeN-controlled, to understand through semi-structured, qualitative interviews their experience of participation in broader epidemic control efforts. Complementary interviews held with two nephrology teams and a senior representative of the grassroots-level National Health Forum operating in the same area, provided necessary contrast. Interview questions were informed by reference to the Adaptation and Development after Persecution and Trauma (ADAPT) model [1] as applicable in post-conflict environments like El salvador to analyze contextual factors influencing community participation. Findings: Farmers are scarcely involved in wider MeN prevention efforts in El salvador despite greater National Health System emphasis on encouraging community participation since the approval of the 2009 Health Reform [2]. This study found that widespread insecurity due to gang warfare, declining family and social networks due to high murder rates and international migration, and unresolved sense of injustice over unremitting poverty are among major factors with potential destructive effect on farmer participation. Conclusions: Health system-led MeN prevention responses need to encompass attention to persisting social vulnerabilities in economically and socially marginalized communities in order to enhance farmer participation in this effort. This paper concludes with some recommendations on how this can be done.

关键词： El salvador Meso-American Nephropathy CKDu Pesticides Dehydration Heat Stress Farmer Resilience