Methodology for the design of a multilayer polymeric membrane system with potential use in hemofiltration

Chronic kidney disease is generally complicated by poor care or by ignoring it. Among the causes that influence these conditions are obesity, diabetes, smoking, or genetic inheritance. Coordinated efforts are currently being made in multiple countries to control a strong case rate. The clinical techniques of treatment rely on the efficiency of blood purification (function that´s done by kidneys in organisms). Therefore, there is great interest in the development of devices that accomplish this function. Hemofiltration through porous membranes is an efficient process, but the flow conditions in a microchannel system can be complex. Analysis of blood flow in a parameterized conduit arrangement shows streams with desired trajectories, others are held back (stagnant), and others return to the stream from which it´s separated. In addition, the friction conditions and the reduction of the area drastically reduce the movement of the fluid, promoting clogging and consequently the inhibition of filtering. Based on these simulation results, it was proposed that the membrane coupling system could be modified to eliminate extensive flow in conduits generating a new concept of separation through a threshold.

Anionic Polymerization Using Flow Microreactors

Flow microreactors are expected to make a revolutionary change in chemical synthesis involving various fields of polymer synthesis. In fact, extensive flow microreactor studies have opened up new possibilities in polymer chemistry including cationic polymerization, anionic polymerization, radical polymerization, coordination polymerization, polycondensation and ring-opening polymerization. This review provides an overview of flow microreactors in anionic polymerization and their various applications.

CASA DO FORNO: instituição sócio-alimentar de Araí e Taiassuí, nordeste paraense

Sinopse:A casa do forno (em outros lugares do Brasil é chamada de casa de farinha) é um dos elementos mais importantes no processo produtivo que permite que a mandioca se transforme em um conjunto de bens alimentícios, como: farinha d’água, goma, tucupi, etc., que são comidas (usa-se o termo comidas e não alimentos para reforçar o traço de sociabilidade proporcionado pela comida em situações coletivas, como comensalidade) que povoam os mercados e as mesas dos habitantes do nordeste paraense e que conferem considerável importância histórica, econômica, social e religiosa no lugar. (Picanço, 2018). Desse modo, a casa do forno, materializa-se em um espaço fulcral para a história da mandioca e dos habitantes de Araí e Taiassuí (comunidades rurais e produtoras de roça de mandioca no nordeste paraense), pois, ao mesmo tempo em que se constitui em um lugar onde são “paridos” todos os descendentes da mandioca, ela também funciona como um espaço de trocas de experiências, onde o saber fazer as comidas oriundas da mandioca é ensinado, aprendido e mantido de geração em geração. As casas do forno ajudam na composição socioespacial de Araí e Taiassuí, pois onde tem uma roça, nas proximidades também se encontra uma delas. Por isso, a casa do forno, ao mesmo tempo em que é pensada e concebida como uma instituição socioalimentar, também é compreendida como uma “maternidade”, um laboratório onde os frutos da mandioca são paridos, são nascidos. Como diria Marcena (2012, p. 52), ela é o “ventre da farinha, nascedoura de todas as farinhas de mandioca preparadas e também dos beijus [...], a casa de farinha se constitui como uma instituição socioalimentar [...], desde os primórdios da invenção da brasilidade [...].” Ela também se revela um lugar de interações sociais e sociabilidades que são alimentadas em um extenso fluxo de pessoas, de distintas famílias que ali trabalham em cooperação, mas também conta com a labuta dos não humanos, que ao mesmo tempo em que são singulares, tornam-se complexos, os quais não estão simplesmente ali, eles habitam naquelas casas do forno, onde desempenham atividades laborais específicas (Velthem, 2007), das quais a mandioca depende para gerar seus frutos. São eles e elas: a gamela grande, a gamela pequena, a mão de pilão, a peneira, a prensa, as vassouras, os tipitis, os rodos, o forno e, em alguns casos, o ralo e/ou o catitu, sobre os quais “[...] há [...] nítida percepção de que trabalham” (Velthem, 2007, p. 622). Portanto são das experiências laborais, dos humanos e não humanos, que dão vida aos descendentes da mandioca na casa do forno, que “falam” as imagens deste ensaio fotográfico. sinopsis:The furnace house (in other places of Brazil and called flour house) is one of the most important elements in the production process that allows cassava to become a set of foodstuffs, such as: water flour, gum, tucupi, etc., which are foods ( the term food is used to reinforce the sociability trait provided by food in collective situations such as commensality) that populate the markets and tables of the inhabitants of northeastern Pará and that confer considerable historical, economic, social and religious importance in the place. (PICANÇO, 2018). In this way, the furnace house is materialized in a central space for the history of cassava and the inhabitants of Araí and Taiassuí (rural communities and producers of cassava in northeastern of Pará), since, at the same time, in a place where all the descendants of cassava are "born", it also functions as a space for exchange of experiences, where the know how to make the foods from cassava is taught, learned and maintained from generation to generation. The furnace houses help in the socio-spatial composition of Araí and Taiassuí, because where there is a garden, there is also one nearby. For this reason, the furnace house, at the same time as it is thought and conceived as a socio-alimentary institution, is also understood as a "maternity", a laboratory where the fruits of cassava are born. How could say Marcena (2012, p. 52), it is the "belly of flour, born of all prepared cassava flour and also of the beijus [...], the flour house constitutes as a socio-alimentary institution...], from the earliest days of the invention of Brazilianness. It also reveals itself as a place of social interactions and sociabilities that are nurtured in an extensive flow of people, from distinct families who work there in cooperation, but also relies on the toil of not human, who at the same time are singular, make (VELTHEM, 2007), on which cassava depends to produce its fruits. They are: large trough, small trough, the hand of pestle, sieve, press, brooms, tipitis, rodos, furnace and, in some cases, drain and / or catitu, over which "[...] there is a clear perception that they work" (VELTHEM, 2007, p.622). Therefore, it is from the human and not human labor experiences that give life to the descendants of cassava in the furnace house that "speak" the images of this photographic essay.Palabras-chave:Casa do forno. Mandioca. Pará.Key-words:Furnace house. Cassava. Pará.Ficha técnica:Autora:Miguel de Nazaré Brito PicançoFotografias: Miguel de Nazaré Brito PicançoDireção, Edição de Imagem e Texto: Miguel de Nazaré Brito PicançoFicha técnica:Autora:Miguel de Nazaré Brito PicançoFotografía:Miguel de Nazaré Brito PicançoDirección:Miguel de Nazaré Brito Picanço

Differences in common heritable blood immune cell populations may underlie MS susceptibility and progression

A promising new avenue of MS research that may lead to a better understanding of pathogenesis, progression and therapeutic response, and to development of new therapies, comes from the recent identification of defined immune cell populations that are highly heritable. Such stable populations have been identified in three recent papers using extensive flow cytometric panels to investigate twin and family cohorts. They showed that while most of the variation in immune cell populations between individuals was not heritable, some was. This heritability was sometimes very high, and the authors concluded that it likely contributes to variability in response among individuals for disease and drug response traits.

3-D CFD simulations of hydrodynamics in the Sulejow dam reservoir

This paper reports the processes by which a single-phase 3-D CFD model of hydrodynamics in a 17-km-long dam reservoir was developed, verified and tested. A simplified VOF model of flow was elaborated to determine the effect of wind on hydrodynamics in the lake. A hexahedral mesh with over 17 million elements and a k-ω SST turbulence model were defined for single-phase simulations in steady-state conditions. The model was verified on the basis of the extensive flow measurements (StreamPro ADCP, USA). Excellent agreement (average error of less than 10%) between computed and measured velocity profiles was found. The simulation results proved a strong effect of wind on hydrodynamics in the lake, especially on the development of the water circulation pattern in the lacustrine zone.

A PROCESS-BASED APPROACH TO SEDIMENT TRANSPORT

A process-based model for the Yangtze Estuary is constructed to study the sediment transport in the estuary. The proposed model covers the entire tidal region of the estuary, the Hangzhou Bay and a large part of the adjacent sea. The dominant processes, fluvial and tidal, are included in the model. The calibration of the model against extensive flow, water level, salinity and suspended sediment data shows a good representation of observed phenomena. With the present calibrated and validated model, the residual flow field and the residual sediment transport field are obtained. The residual sediment transport pattern gives insight into the morphological behaviour of the mouth bars.

Visualizing "Race" in the Eighteenth Century

This paper looks at the conditions of the emergence of "race" as a new scientific category during the eighteenth century, arguing that two modes of discourse and visualization played a significant role: that on society, civility, and civilization——as found principally in the travel literature——and that on nature, as found in natural history writings, especially in botanical classifications. The European colonizing enterprise had resulted in an extensive flow of new objects at every level. Visual representations of these new objects circulated in the European cultural world and were transferred and transformed within travelogue and natural history writings. The nature, boundaries, and potentialities of humankind were discussed in this exchange within the conceptual grid of classifications and their visual representations. Over the course of the century the discourse on society, civility, and civilization collapsed into the discourse on nature. Humans became classified and visually represented along the same lines as flora, according to similar assumptions about visible features. Concurrently, these visible features were related necessarily to bundles of social, civilized, and cognitive characteristics taken from the discourse on society, civility, civilization, as found in the contemporaneous travelogue.

Viscous simulation of shock-reflection hysteresis in overexpanded planar nozzles

A computational fluid dynamics simulation of the flow in an overexpanded planar nozzle shows the existence of Mach-reflection hysteresis inside the nozzle. Previous simulations have dealt only with the flow outside the nozzle and thus concluded that the hysteresis phenomenon takes place outside the nozzle even when viscous effects are introduced. When including the geometry of the nozzle in the simulation it becomes evident that flow separation will occur before the transition from regular to Mach reflection for all relevant Mach numbers. The simulation reveals complex changes in the flow structure as the pressure ratio between the ambient and the jet is increased and decreased. The pressure along the nozzle wall downstream of the separation point is found to be less than the ambient pressure, and a modification of the Schilling curve fit is suggested for cases of extensive flow separation.