TRANSIENT MODELLING OF A NATURAL CIRCULATION LOOP UNDER VARIABLE PRESSURE

The objective of the present work is to model the transient operation of a natural circulation loop, which is one-tenth scale in height to a typical Passive Residual Heat Removal system (PRHR) of an Advanced Pressurized Water Nuclear Reactor and was designed to meet the single and two-phase ow similarity criteria to it. The loop consists of a core barrel with electrically heated rods, upper and lower plena inter- connected by hot and cold pipe legs to a seven-tube shell heat exchanger of countercurrent design, and an expansion tank with a descending tube. A long transient characterized the loop operation, during which a phenomenon of self-pressurization, without self-regulation of the pressure, was experimentally observed. This represented a unique situation, named natural circulation under variable pressure (NCVP). The self-pressurization was originated in the air trapped in the expansion tank and compressed by the loop water dilatation, as it heated up during each experiment. The mathematical model, initially oriented to the single-phase ow, included the heat capacity of the structure and employed a cubic polynomial approximation for the density, in the buoyancy term calculation. The heater was modelled taking into account the di erent heat capacities of the heating elements and the heater walls. The heat exchanger was modelled considering the coolant heating, during the heat exchanging process. The self-pressurization was modelled as an isentropic compression of a perfect gas. The whole model was computationally im-plemented via a set of nite di erence equations. The corresponding computational algorithm of solution was of the explicit, marching type, as for the time discretization, in an upwind scheme, regarding the space discretization. The computational program was implemented in MATLAB. Several experiments were carried out in the natural circulation loop, having the coolant ow rate and the heating power as control parameters. The variables used in the comparison between experimental and calculated data were some relevant loop temperatures and pressures. The results obtained from the computational model agree qualitatively well with the experimental NCVP data

Quantum Statistical Complexity Measure as a Signaling of Correlation Transitions

We introduce a quantum version for the statistical complexity measure, in the context of quantum information theory, and use it as a signaling function of quantum order–disorder transitions. We discuss the possibility for such transitions to characterize interesting physical phenomena, as quantum phase transitions, or abrupt variations in correlation distributions. We apply our measure on two exactly solvable Hamiltonian models: the 1D-Quantum Ising Model (in the single-particle reduced state), and on Heisenberg XXZ spin-1/2 chain (in the two-particle reduced state). We analyze its behavior across quantum phase transitions for finite system sizes, as well as in the thermodynamic limit by using Bethe Ansatz technique

Expression of functional recombinant human growth hormone in transgenic soybean seeds

We produced human growth hormone (hGH), a protein that stimulates growth and cell reproduction, in genetically engineered soybean [Glycine max (L.) Merrill] seeds. Utilising the alpha prime (alpha') subunit of beta-conglycinin tissue-specific promoter from soybean and the alpha-Coixin signal peptide from Coix lacryma-jobi, we obtained transgenic soybean lines that expressed the mature form of hGH in their seeds. Expression levels of bioactive hGH up to 2.9% of the total soluble seed protein content (corresponding to approximately 9 g kg(-1)) were measured in mature dry soybean seeds. The results of ultrastructural immunocytochemistry assays indicated that the recombinant hGH in seed cotyledonary cells was efficiently directed to protein storage vacuoles. Specific bioassays demonstrated that the hGH expressed in the soybean seeds was fully active. The recombinant hGH protein sequence was confirmed by mass spectrometry characterisation. These results demonstrate that the utilisation of tissue-specific regulatory sequences is an attractive and viable option for achieving high-yield production of recombinant proteins in stable transgenic soybean seeds

A Psicologia racial no Brasil (1918-1929) The race Psychology in Brazil (1918-1929)

As teorias raciais chegaram ao Brasil por volta de 1869. Neste artigo procuramos demonstrar como estas teorias entraram no âmbito das ciências psicológicas e direcionaram conceitos e práticas. Foram analisados os anais da Sociedade Eugênica de São Paulo (1919) e os trabalhos apresentados no 1º Congresso Brasileiro de Eugenia (1929), que tiveram como meta "melhorar a raça nacional". Tanto aquela instituição quanto este evento científico contaram com a participação de psicólogos, psiquiatras e antropólogos que se aproximaram do racismo científico, muito difundido pelo mundo no início do século XX. Esta aproximação gerou uma "Psicologia Racial" no Brasil, a qual pretendia reduzir os saberes psicológicos a uma suposta problemática racial.<br>The arrival of racist theories in Brazil happened around 1869. The aim of this paper was to demonstrate how those theories got into the psychological sciences and conducted their concepts and practices. Documents from Sao Paulo Eugenic Society's archives (1919) and from the 1st Brazilian Eugenics Conference (1929) have been analyzed, both proving to be committed with the "national race improvement". Many psychologists, psychiatrists and anthropologists related to scientific racism - spread around the world in early 20th century - took part of the institution as well as the conference. This fact brought about the "race psychology" in Brazil, which intended to reduce the psychological knowledge to a hypothetic racial problem

Passagens para o Estado-nação: a tese de Costa Pinto Passages to the nation-state: the Costa Pinto's thesis

O artigo discute uma pesquisa clássica da tradição sociológica brasileira: Lutas de famílias no Brasil (1949), de Luiz de Aguiar Costa Pinto. O objetivo principal é evidenciar e analisar sua significação teórica mais ampla para o entendimento da formação do Estado-nação no Brasil. Mostra como Lutas de famílias no Brasil contribui para desestabilizar a oposição dualista com que a relação entre público e privado vinha sendo interpretada no pensamento social brasileiro.<br>The article discusses a classical research of Brazilian sociological tradition: Lutas de famílias no Brasil (1949), by Luiz de Aguiar Costa Pinto. The main objective is to demonstrate and analyze their theoretical meaning for understanding the formation of the Nation-state in Brazil. It shows how Costa Pinto's research contributes to destabilize the dualistic opposition between public and private on the Brazilian social thought