El proyecto de vivienda como laboratorio de estrategias para Sejima y Nishizawa de 1987 a 2010

Como indica el título, esta tesis plantea el estudio de la arquitectura doméstica elaborada por los arquitectos japoneses Kazuyo Sejima y Ryue Nishizawa. Más concretamente, la investigación se ciñe a un conjunto integrado por veinticinco casas que los arquitectos proyectaron entre 1987, momento en el que Sejima establece su propia oficina, y 2010, fecha en la que el reconocimiento del trabajo que ambos venían desarrollando queda certificado a nivel internacional, ya que ese año son galardonados con el premio Pritzker y comisarían la Bienal deVenecia. Del estudio conjunto y sistemático de estos proyectos, y de sus distintas versiones se espera poder obtener una serie de criterios exegéticos que permitan comprenderlos y explicarlos mejor, relacionándolos entre sí de manera coherente. A estos criterios es a lo que hemos denominado estrategias. En el momento en el que se inicia esta investigación se detectó un vacío editorial respecto al tema tratado, apenas había textos, propios o ajenos que abordaran esta faceta de la obra de Sejima y Nishizawa en profundidad. No en vano, algunos críticos han acuñado el apelativo de "arquitectos sin palabras" para referirse, tanto a ellos como a la generación de arquitectos que la pareja encabeza, dando a entender que se trata de una arquitectura carente de explicación.1 Sin embargo, esta investigación sostiene que el hecho de que los arquitectos no hablen en exceso de su obra y mantengan una actitud centrada en desarrollar de forma práctica su trabajo no quiere decir que prescindan de realizar operaciones compositivas altamente idealizadas y abstractas, refrendadas por un marco cultural y teórico que se pueda describir. Tras recopilar, ordenar y analizar un número lo suficientemente amplio como para ser significativo de las manifestaciones verbales que los arquitectos han realizado a lo largo del periodo estudiado, se ha observado que de entre todos los términos que los dos socios que integran SANAA emplean para describir sus proyectos, uno de los más relevantes y quizás también el más general resulta la palabra “sistema”.2 El modo en el que ambos describen los principios de su arquitectura, diferenciando entre los componentes del programa, y las relaciones que se establecen entre éstos, y entre ellos y el exterior permiten sostener que no se trata de un uso accidental término. Paralelamente, al mismo tiempo que se indaga sobre el corpus intelectual de esta teoría se intenta detallar las circunstancias que favorecieron tal trasvase de ideas entre Occidente y Japón y como acabaron llegando al ámbito de estos arquitectos. Al amparo de este marco teórico y tras redibujar las viviendas documentadas, se intentará describir los rasgos de la estructura material de las viviendas analizadas, así como cartografiar los patrones organizativos que las caracterizan. Para ello se empleará el rigor instrumental que aporta la teoría de grafos como método habitual para la representación, estudio y caracterización de sistemas. Los resultados de la investigación evidencian que hay una serie de estrategias — tanto materiales como organizativas— que enunciadas en sus primeros proyectos se van desarrollando en obras posteriores, conformado sistemas que están paulatinamente más organizados. Y que llegado un punto en la trayectoria de estos arquitectos, se observa que tales estrategias, se van superponiendo de distinta forma en diversos proyectos, por lo que es posible agruparlos y hablar de ellos atendiendo a características comunes. Finalmente, el estudio concluye que tanto a nivel material como reladonal, bien podría decirse que en el periodo estudiado, las estrategias empleadas por Sejima y Nishizawa para elaborar su arquitectura doméstica persiguen un objetivo común que se fundamenta en la elaboración de planteamientos sintéticos que les permiten explorar y responder creativamente ante las disyuntivas previamente establecidas, precisamente explotando el potencial de las paradojas que las originan. ABSTRACT As the title suggest itself, this thesis deals about the study of domestic architecture developed by Japanese architects Kazuyo Sejima and Ryue Nishizawa. More specifically, research focus its attention on a group of twenty five houses that both architects projected from 1987, when Sejima establishes her own practice, and 2010, as the moment in which their work obtains international acknowledgment, since this year they are awarded the Pritzker prize and cúrate the Venice Biennale. From the combined and systematic study of all these projects, and their different versions are expected to obtain a series of exegetical criteria to relate to each other, understand and explain better. These criteria are what we cali strategies. By the time when this research began, an editorial emptiness about the treaty issue was detected; there were barely texts that addressed this aspect of the work of Sejima and Nishizawa in depth, neither the ones written by the architects themselves ñor by other authors. Some critics have coined the ñame "wordless generation" to refer to both them as to the generation of architects that the couple leads, implying that it is an architecture devoid of explanation.3 However, this study argües that the fact that architects do not speak too much about his work and keep themselves focused on developing practical work attitude does not mean that dispense perform highly idealized and abstract compositional operations, fueled by a frame cultural and theoretical that can be described. After collect, sort and analyze a large enough number of verbal statements done by the architects about their work as to be meaningful, it was observed that of all the terms that the two partners that intégrate SANAA used to describe their projects, one of the most important and, perhaps one of the most general, is the word "system".4 The way in which both describe the principies of their architecture distinguishing between program components and the relationships established between them, and between them and the outside allow us the view that it is not accidental use of a term. Similarly, while it investigates the intellectual corpus of this theory it attempts to explain some of the circumstances that favored such transfer of ideas between the West and Japan and how eventually reaching the scope of these architects. Under this framework and after redraw the documented houses we attempt to describe the characteristics of the material structure of the projects tested, as well as mapping the organizational patterns that characterize them. For this, we use the instrumental rigor that brings graph theory, as a regular method of representation, study and characterization of systems used. The research results show that there are a number of strategies -both material and organizational level- that once they are set out in its first projects are developed in later works. Bringing up systems that are gradually more and more organized. And at one point in the career of these architects, such strategies are observed, they are superimposed differently on various projects, making it possible to group them and discuss them according to common characteristics. Finally, the study condueles that both materially and organizational it could be said that in the period studied, the strategies employed by Sejima and Nishizawa to develop its domestic architecture pursue a common goal, which is based on the development of synthetic approaches that allow them explore and respond creatively to the previously established dilemmas precisely exploiting the paradoxical potential that originates them.

GESTÃO DE RELAÇÕES ESTRATÉGICAS INTERPESSOAIS NAS ALIANÇAS CORPORATIVAS (GRE): SINERGIA DE VALOR NA GESTÃO INTEGRADA DE RH

Este trabalho pretende apresentar e compreender o papel da gestão estratégica de pessoas, dentro de uma visão que contempla as relações interorganizacionais fora dos limites tradicionais de seu escopo nas empresas e expandidas além das dimensões formais e fronteiras que permeiam uma organização. Este estudo estabelece a importância e sistemáticas da gestão de atividades de RH, compartilhadas com a cadeia de valor externa, analisando-as nas práticas com os canais de distribuição junto aos clientes. Esta área organizacional é denominada pelo autor de GRE - Gestão das Relações Estratégicas. Baseando-se em uma pesquisa exploratória em 26 empresas, organizada a partir de cinco empresas nodais e seus canais de distribuição, utilizou-se a aplicação de um questionário de pesquisa com escala Likert e entrevistas pessoais semi-estruturadas junto aos gestores e profissionais de diversas áreas, bem como o tratamento estatístico dos dados com o programa SPSS, indicando a confirmação das questões de pesquisa relativas a GRE como sendo uma proposta de expansão das atividades do RH, focando em como se pode e devem entregar valor para a organização, para os aliados estratégicos, os investidores e fundamentalmente para os clientes.(AU)

GESTÃO DE RELAÇÕES ESTRATÉGICAS INTERPESSOAIS NAS ALIANÇAS CORPORATIVAS (GRE): SINERGIA DE VALOR NA GESTÃO INTEGRADA DE RH

Este trabalho pretende apresentar e compreender o papel da gestão estratégica de pessoas, dentro de uma visão que contempla as relações interorganizacionais fora dos limites tradicionais de seu escopo nas empresas e expandidas além das dimensões formais e fronteiras que permeiam uma organização. Este estudo estabelece a importância e sistemáticas da gestão de atividades de RH, compartilhadas com a cadeia de valor externa, analisando-as nas práticas com os canais de distribuição junto aos clientes. Esta área organizacional é denominada pelo autor de GRE - Gestão das Relações Estratégicas. Baseando-se em uma pesquisa exploratória em 26 empresas, organizada a partir de cinco empresas nodais e seus canais de distribuição, utilizou-se a aplicação de um questionário de pesquisa com escala Likert e entrevistas pessoais semi-estruturadas junto aos gestores e profissionais de diversas áreas, bem como o tratamento estatístico dos dados com o programa SPSS, indicando a confirmação das questões de pesquisa relativas a GRE como sendo uma proposta de expansão das atividades do RH, focando em como se pode e devem entregar valor para a organização, para os aliados estratégicos, os investidores e fundamentalmente para os clientes.(AU)

AS RELAÇÕES ENTRE GESTÃO DA DIVERSIDADE E CULTURA ORGANIZACIONAL EM UMA EMPRESA DO SETOR PORTUÁRIO DO RIO DE JANEIRO

A cultura de uma organização é importante para que seus colaboradores possuam mesmos objetivos e valores. Porém, em busca de manter uma estratégia competitiva e agir de forma responsável na comunidade em que se encontra, a empresa precisa inovar e adaptar-se. A gestão da diversidade apresenta-se como uma válida forma de enfrentar estes novos desafios e exigências. Contudo, há muitos obstáculos para que uma gestão da diversidade seja bem-sucedida. Este estudo propõe-se em entender como a diversidade pode afetar a cultura de uma organização. Além disso, como a cultura pode afetar a estratégia de gestão da diversidade. Foi utilizado para este objetivo um estudo de caso em profundidade com seis entrevistas. As entrevistas foram apoiadas em um roteiro semi estruturado. A análise dos dados obtidos foi feita pela análise de conteúdo. De acordo com a pesquisa realizada, sugere que a cultura organizacional e a gestão da diversidade estão diretamente conectadas e que podem influenciar positivamente uma a outra, porém precisam manter um equilíbrio em suas ações para que não causem prejuízos à organização.

Female preference for swords in Xiphophorus helleri reflects a bias for large apparent size

Swordtail fish (Poeciliidae: genus Xiphophorus) are a paradigmatic case of sexual selection by sensory exploitation. Female preference for males with a conspicuous “sword” ornament is ancestral, suggesting that male morphology has evolved in response to a preexisting bias. The perceptual mechanisms underlying female mate choice have not been identified, complicating efforts to understand the selection pressures acting on ornament design. We consider two alternative models of receiver behavior, each consistent with previous results. Females could respond either to specific characteristics of the sword or to more general cues, such as the apparent size of potential mates. We showed female swordtails a series of computer-altered video sequences depicting a courting male. Footage of an intact male was preferred strongly to otherwise identical sequences in which portions of the sword had been deleted selectively, but a disembodied courting sword was less attractive than an intact male. There was no difference between responses to an isolated sword and to a swordless male of comparable length, or between an isolated sword and a homogenous background. Female preference for a sworded male was abolished by enlarging the image of a swordless male to compensate for the reduction in length caused by removing the ornament. This pattern of results is consistent with mate choice being mediated by a general preference for large males rather than by specific characters. Similar processes may account for the evolution of exaggerated traits in other systems.

Selective maintenance of allozyme differences among sympatric host races of the apple maggot fly

Whether phytophagous insects can speciate in sympatry when they shift and adapt to new host plants is a controversial question. One essential requirement for sympatric speciation is that disruptive selection outweighs gene flow between insect populations using different host plants. Empirical support for host-related selection (i.e., fitness trade-offs) is scant, however. Here, we test for host-dependent selection acting on apple (Malus pumila)- and hawthorn (Crataegus spp.)-infesting races of Rhagoletis pomonella (Diptera: Tephritidae). In particular, we examine whether the earlier fruiting phenology of apple trees favors pupae in deeper states of diapause (or with slower metabolisms/development rates) in the apple fly race. By experimentally lengthening the time period preceding winter, we exposed hawthorn race pupae to environmental conditions typically faced by apple flies. This exposure induced a significant genetic response at six allozyme loci in surviving hawthorn fly adults toward allele frequencies found in the apple race. The sensitivity of hawthorn fly pupae to extended periods of warm weather therefore selects against hawthorn flies that infest apples and helps to maintain the genetic integrity of the apple race by counteracting gene flow from sympatric hawthorn populations. Our findings confirm that postzygotic reproductive isolation can evolve as a pleiotropic consequence of host-associated adaptation, a central tenet of nonallopatric speciation. They also suggest that one reason for the paucity of reported fitness trade-offs is a failure to consider adequately costs associated with coordinating an insect’s life cycle with the phenology of its host plant.

Evolutionary analyses of hedgehog and Hoxd-10 genes in fish species closely related to the zebrafish

The study of development has relied primarily on the isolation of mutations in genes with specific functions in development and on the comparison of their expression patterns in normal and mutant phenotypes. Comparative evolutionary analyses can complement these approaches. Phylogenetic analyses of Sonic hedgehog (Shh) and Hoxd-10 genes from 18 cyprinid fish species closely related to the zebrafish provide novel insights into the functional constraints acting on Shh. Our results confirm and extend those gained from expression and crystalline structure analyses of this gene. Unexpectedly, exon 1 of Shh is found to be almost invariant even in third codon positions among these morphologically divergent species suggesting that this exon encodes for a functionally important domain of the hedgehog protein. This is surprising because the main functional domain of Shh had been thought to be that encoded by exon 2. Comparisons of Shh and Hoxd-10 gene sequences and of resulting gene trees document higher evolutionary constraints on the former than on the latter. This might be indicative of more general evolutionary patterns in networks of developmental regulatory genes interacting in a hierarchical fashion. The presence of four members of the hedgehog gene family in cyprinid fishes was documented and their homologies to known hedgehog genes in other vertebrates were established.

Chloroplast small heat shock proteins: Evidence for atypical evolution of an organelle-localized protein

Knowledge of the origin and evolution of gene families is critical to our understanding of the evolution of protein function. To gain a detailed understanding of the evolution of the small heat shock proteins (sHSPs) in plants, we have examined the evolutionary history of the chloroplast (CP)-localized sHSPs. Previously, these nuclear-encoded CP proteins had been identified only from angiosperms. This study reveals the presence of the CP sHSPs in a moss, Funaria hygrometrica. Two clones for CP sHSPs were isolated from a F. hygrometrica heat shock cDNA library that represent two distinct CP sHSP genes. Our analysis of the CP sHSPs reveals unexpected evolutionary relationships and patterns of sequence conservation. Phylogenetic analysis of the CP sHSPs with other plant CP sHSPs and eukaryotic, archaeal, and bacterial sHSPs shows that the CP sHSPs are not closely related to the cyanobacterial sHSPs. Thus, they most likely evolved via gene duplication from a nuclear-encoded cytosolic sHSP and not via gene transfer from the CP endosymbiont. Previous sequence analysis had shown that all angiosperm CP sHSPs possess a methionine-rich region in the N-terminal domain. The primary sequence of this region is not highly conserved in the F. hygrometrica CP sHSPs. This lack of sequence conservation indicates that sometime in land plant evolution, after the divergence of mosses from the common ancestor of angiosperms but before the monocot–dicot divergence, there was a change in the selective constraints acting on the CP sHSPs.

Interaction of batrachotoxin with the local anesthetic receptor site in transmembrane segment IVS6 of the voltage-gated sodium channel

The voltage-gated sodium channel is the site of action of more than six classes of neurotoxins and drugs that alter its function by interaction with distinct, allosterically coupled receptor sites. Batrachotoxin (BTX) is a steroidal alkaloid that binds to neurotoxin receptor site 2 and causes persistent activation. BTX binding is inhibited allosterically by local anesthetics. We have investigated the interaction of BTX with amino acid residues I1760, F1764, and Y1771, which form part of local anesthetic receptor site in transmembrane segment IVS6 of type IIA sodium channels. Alanine substitution for F1764 (mutant F1764A) reduces tritiated BTX-A-20-α-benzoate binding affinity, causing a 60-fold increase in Kd. Alanine substitution for I1760, which is adjacent to F1764 in the predicted IVS6 transmembrane alpha helix, causes only a 4-fold increase in Kd. In contrast, mutant Y1771A shows no change in BTX binding affinity. For wild-type and mutant Y1771A, BTX shifted the voltage for half-maximal activation ≈40 mV in the hyperpolarizing direction and increased the percentage of noninactivating sodium current to ≈60%. In contrast, these BTX effects were eliminated completely for the F1764A mutant and were reduced substantially for mutant I1760A. Our data suggest that the BTX receptor site shares overlapping but nonidentical molecular determinants with the local anesthetic receptor site in transmembrane segment IVS6 as well as having unique molecular determinants in transmembrane segment IS6, as demonstrated in previous work. Evidently, BTX conforms to a domain–interface allosteric model of ligand binding and action, as previously proposed for calcium agonist and antagonist drugs acting on l-type calcium channels.

Localization of neuropeptide Y Y1 receptors in cerebral blood vessels

The localization of neuropeptide Y (NPY) Y1 receptor (R) -like immunoreactivity (LI) has been studied in cerebral arteries and arterioles of the rat by immunohistochemistry using fluorescence, confocal, and electron microscopy. High levels of Y1-R-LI were observed in smooth muscle cells (SMCs) in the small arterioles of the pial arterial network, especially on the basal surface of the brain, and low levels in the major basal cerebral arteries. The levels of Y1-R-LI varied strongly between adjacent SMCs. Y1-R-LI was associated with small endocytosis vesicles, mainly on the outer surface of the SMCs, but also on their endothelial side and often laterally at the interface between two SMCs. NPY-immunoreactive (Ir) nerve fibers could not be detected in association with the Y1-R-rich small arterioles but only around arteries with low Y1-R levels. A dense network of central NPY-Ir nerve fibers in the superficial layers of the brain was lying close to the strongly Y1-R-Ir small arterioles. The results indicate that NPY has a profound effect on small arterioles of the brain acting on Y1-Rs, both on the peripheral and luminal side of the SMCs. However, the source of the endogenous ligand, NPY, remains unclear. NPY released from central neurons may play a role, in addition to blood-borne NPY.

Microdomain-dependent Regulation of Lck and Fyn Protein-Tyrosine Kinases in T Lymphocyte Plasma Membranes

Src family protein-tyrosine kinases are implicated in signaling via glycosylphosphatidylinositol (GPI)-anchored receptors. Both kinds of molecules reside in opposite leaflets of the same sphingolipid-enriched microdomains in the lymphocyte plasma membrane without making direct contact. Under detergent-free conditions, we isolated a GPI-enriched plasma membrane fraction, also containing transmembrane proteins, selectively associated with sphingolipid microdomains. Nonionic detergents released the transmembrane proteins, yielding core sphingolipid microdomains, limited amounts of which could also be obtained by detergent-free subcellular fractionation. Protein-tyrosine kinase activity in membranes containing both GPI-anchored and transmembrane proteins was much lower than in core sphingolipid microdomains but was strongly reactivated by nonionic detergents. The inhibitory mechanism acting on Lck and Fyn kinases in these membranes was independent of the protein-tyrosine phosphatase CD45 and was characterized as a mixed, noncompetitive one. We propose that in lymphocyte plasma membranes, Lck and Fyn kinases exhibit optimal activity when juxtaposed to the GPI- and sphingolipid-enriched core microdomains but encounter inhibitory conditions in surrounding membrane areas that are rich in glycerophospholipids and contain additional transmembrane proteins.

Subcellular Localization of Myosin-V in the B16 Melanoma Cells, a Wild-type Cell Line for the dilute Gene

The discovery that the dilute gene encodes a class V myosin led to the hypothesis that this molecular motor is involved in melanosome transport and/or dendrite outgrowth in mammalian melanocytes. The present studies were undertaken to gain insight into the subcellular distribution of myosin-V in the melanoma cell line B16-F10, which is wild-type for the dilute gene. Immunofluorescence studies showed some degree of superimposed labeling of myosin-V with melanosomes that predominated at the cell periphery. A subcellular fraction highly enriched in melanosomes was also enriched in myosin-V based on Western blot analysis. Immunoelectron microscopy showed myosin-V labeling associated with melanosomes and other organelles. The stimulation of B16 cells with the α-melanocyte-stimulating hormone led to a significant increase in myosin-V expression. This is the first evidence that a cAMP signaling pathway might regulate the dilute gene expression. Immunofluorescence also showed an intense labeling of myosin-V independent of melanosomes that was observed within the dendrites and at the perinuclear region. Although the results presented herein are consistent with the hypothesis that myosin-V might act as a motor for melanosome translocation, they also suggest a broader cytoplasmic function for myosin-V, acting on other types of organelles or in cytoskeletal dynamics.

Evolutionary theory predicts late-life mortality plateaus

Most demographic data indicate a roughly exponential increase in adult mortality with age, a phenomenon that has been explained in terms of a decline in the force of natural selection acting on age-specific mortality. Scattered demographic findings suggest the existence of a late-life mortality plateau in both humans and dipteran insects, seemingly at odds with both prior data and evolutionary theory. Extensions to the evolutionary theory of aging are developed which indicate that such late-life mortality plateaus are to be expected when enough late-life data are collected. This expanded theory predicts late-life mortality plateaus, with both antagonistic pleiotropy and mutation accumulation as driving population genetic mechanisms.

Corticotropin-releasing hormone causes antidiuresis and antinatriuresis by stimulating vasopressin and inhibiting atrial natriuretic peptide release in male rats

In both normally hydrated and volume-expanded rats, there was a biphasic effect of corticotropin-releasing hormone (CRH) (1–10 μg, i.v.) on renal function. Within the first hour, CRH caused antidiuresis, antinatriuresis, and antikaliuresis together with reduction in urinary cGMP output that, in the fourth hour, were replaced by diuresis, natriuresis, and kaliuresis accompanied by increased cGMP output. Plasma arginine vasopressin (AVP) concentrations increased significantly within 5 min, reached a peak at 15 min, and declined by 30 min to still-elevated values maintained for 180 min. Changes in plasma atrial natriuretic peptide (ANP) were the mirror image of those of AVP. Plasma ANP levels were correlated with decreased ANP in the left ventricle at 30 min and increased ANP mRNA in the right atrium at 180 min. All urinary changes were reversed by a potent AVP type 2 receptor (V2R) antagonist. Control 0.9% NaCl injections evoked an immediate increase in blood pressure and heart rate measured by telemetry within 3–5 min. This elevation of blood pressure was markedly inhibited by CRH (5 μg). We hypothesize that the effects are mediated by rapid, direct vasodilation induced by CRH that decreases baroreceptor input to the brain stem, leading to a rapid release of AVP that induces the antidiuresis by direct action on the V2Rs in the kidney. Simultaneously, acting on V2Rs in the heart, AVP inhibits ANP release and synthesis, resulting in a decrease in renal cGMP output that is responsible for the antinatriuretic and antikaliuretic effects.

Conserved stem–loop structures in the HIV-1 RNA region containing the A3 3′ splice site and its cis-regulatory element: possible involvement in RNA splicing

The HIV-1 transcript is alternatively spliced to over 30 different mRNAs. Whether RNA secondary structure can influence HIV-1 RNA alternative splicing has not previously been examined. Here we have determined the secondary structure of the HIV-1/BRU RNA segment, containing the alternative A3, A4a, A4b, A4c and A5 3′ splice sites. Site A3, required for tat mRNA production, is contained in the terminal loop of a stem–loop structure (SLS2), which is highly conserved in HIV-1 and related SIVcpz strains. The exon splicing silencer (ESS2) acting on site A3 is located in a long irregular stem–loop structure (SLS3). Two SLS3 domains were protected by nuclear components under splicing condition assays. One contains the A4c branch points and a putative SR protein binding site. The other one is adjacent to ESS2. Unexpectedly, only the 3′ A residue of ESS2 was protected. The suboptimal A3 polypyrimidine tract (PPT) is base paired. Using site-directed mutagenesis and transfection of a mini-HIV-1 cDNA into HeLa cells, we found that, in a wild-type PPT context, a mutation of the A3 downstream sequence that reinforced SLS2 stability decreased site A3 utilization. This was not the case with an optimized PPT. Hence, sequence and secondary structure of the PPT may cooperate in limiting site A3 utilization.