El borde urbano: un acercamiento paisajístico y funcional de los límites del suelo urbanizado en las ciudades medias españolas

Asistimos a una evolución en la relación entre ciudad y resto del territorio. Este cambio desemboca en la eliminación del límite. La ciudad moderna se diluye en el territorio: el límite tradicional que separaba espacio urbano de espacio natural se ha diluído. La Discontinuidad entre la ciudad y el campo no se produce de forma definida (bien mediante un límite abrupto o con un gradiente) sino mediante una interfase fragmentada de funcionamiento inadecuado y que, además, no permite una clara identificación paisajística, creando problemas de eficiencia y de identidad urbana. El primer objetivo de esta investigación será determinar si existe la posibilidad de dibujar gráficamente el límite de nuestras ciudades medias para detectar si realmente existe y de qué manera se produce. A partir de aquí se realizará una catalogación del límite con el objetivo de determinar si existe algún tipo predominante sobre los demás. La comparativa entre las ciudades nos aportará la visión de en qué medida el tipo de límite es común o por el contrario singular a unas características propias de cada ciudad. El muestreo se realiza sobre un total de seis ciudades medias españolas, todas ellas capitales de provincia y con una población entre 100.000 y 300.000 habitantes: Vitoria-Gasteiz, Burgos, Pamplona, Valladolid, Lleida y Logroño. El primer paso de la metodología consiste en identificar el límite a través de su representación cartográfica. A partir de aquí se estudia qué limita con qué: cuáles son los usos urbanos que se sitúan en el borde y con qué usos no urbanos limitan. De este modo se hacen cuantificables y por lo tanto medibles. Se establecen las relaciones numéricas de estos usos del suelo y sus porcentajes. El recorrido a lo largo del límite confirma que se trata de un espacio multifuncional. Y se identifica el Límite de lo Común, un límite similar en cuanto a usos y tipologías en todas las ciudades estudiadas. La identidad en el límite se genera a partir de una imagen Genérica (el límite de lo común), una imagen Cerrada, una imagen más o menos Rural, una imagen Cultural (la huella del límite histórico) y finalmente a través de una imagen en Degradación. El límite adquiere una entidad espacial llamada Intefase, compuesta por piezas urbanas dispersas a lo largo de una franja que rodea la ciudad. Este espacio adopta usos y lógicas de localización propios, lo que le confiere una identidad única. En la segunda parte de la tesis se categorizan las diferentes tipologías del límite, el límite según Barreras, según las relaciones campo-ciudad y según aspectos visuales. Los datos confirman que la ciudad media española muestra un aspecto de ciudad dispersa, en diferentes grados de desarrollo; es una ciudad sin barreras que sin embargo se muestra cerrada hacia el campo. ABSTRACT The urban-rural relationship is currently evolving; the in-between boundary is finally been removed. The contemporary city sprawls over the countryside, and the boundary of the traditional city, the urban-rural divide, fades away. Discontinuity between the city and the countryside does not happen in a defined pattern (either by an abrupt or a gradient boundary) but by a malfunctioning rural-urban fringe fragmented and that also does not allow a clear identification landscape, creating problems of efficiency and urban identity. This research focuses on mapping our medium cities boundary, in order to identify whether it exists and how it occurs. The case studies are six medium size Spanish cities with a population between 100.000 and 300.000: Vitoria-Gasteiz, Burgos, Pamplona, Valladolid, Lleida and Logroño. Tracking the boundaries confirms that these are multifunctional spaces. This research defines a new concept called the Common Boundary, that involves similar uses and types in all the boundaries of the case studies. The boundary identity is built up with a Generic image (the common boundary), a closed image, a rural image, a cultural image (the imprint of the historic boundary) and finally with a degradation image. This boundary acquires a spatial entity called Intefase composed of sprawl urban pieces along a rural-urban fringe surrounding the city. New uses and different logical location appear in this fringe, therefore it gives it the uniqueness of the fringe. Finally this research categorizes the different boundary types: the boundary as barriers, the boundary as rural-urban relations and as visual aspects. Examined data confirms that the medium size Spanish city suffers from urban sprawl at different stages. Moreover a city without barriers and closed to the countryside is shown.

Estudio y diseño de elementos acústicos para proporcionar una acústica variable en una sala multifuncional

El objetivo de este proyecto es profundizar en el estudio y diseño de sistemas relacionados con el acondicionamiento acústico para una sala multifuncional. El proyecto se compone de dos partes. Una parte teórica y una parte práctica dónde se aplican los conceptos teóricos aprendidos. La primera parte, está dividida en capítulos en los que se habla de los siguientes temas: Acústica de salas. Para obtener una acústica adecuada en un recinto destinado a varias funciones, se debe contar con una serie de características que lo definan según su uso, por lo que es necesario conocer el tiempo de reverberación y otros parámetros subjetivos para poder caracterizar ese recinto. Materiales para el acondicionamiento acústico, donde se habla de los materiales absorbentes clasificándolos según las frecuencias a las que actúan y de los distintos tipos de difusores. Métodos para conseguir una acústica variable mediante la utilización de elementos físicos variables, citando casos reales de salas multifuncionales. La segunda parte, consiste en la realización de diseños de elementos de acústica variable para una posible utilización en salas polivalentes reales. La herramienta elegida a la hora de la elaboración de estos diseños es el AutoCad. Con esta herramienta se han realizado estos diseños representados en dos y tres dimensiones. ABSTRACT. The objective of this project is to deepen the study and design of systems related to multifunctional room acoustic conditioning. The project is composed of two parts. A theoretical part and a practical part where the learned theoretical concepts are applied. The first part is divided into chapters in which we talk about the following topics: Acoustics of rooms. To obtain proper acoustics in a room intended for various functions, you must have a number of characteristics that define it according to its use, so it is necessary to know the reverberation time and other subjective parameters to characterize the hall. Materials for acoustic conditioning, where we talk about the absorbent materials classified according to frequencies that those materials act and the different types of diffusers. Methods for obtain a variable acoustic by using variable physical elements, mentioning real cases of multi-purpose rooms. The second part deals with designs execution of variable acoustic elements for a possible use in a real multipurpose room. The chosen tool to develop these designs is the AutoCad. These designs have been made with this tool, represented in two and three dimensions.

COMPARAÇÃO DE MODELOS DE AVALIAÇÃO DE DESEMPENHO DE EQUIPES MULTIFUNCIONAIS BASEADOS EM CONCEITOS DE INTERAÇÃO DE GRUPOS E FERRAMENTAS DE ANÁLISE COMPORTAMENTAL

Avaliação de desempenho de equipes multifuncionais é um conceito que tem sido abordado mais freqüentemente nas últimas duas décadas. Diversas teorias e conceitos foram desenvolvidos para tornar as avaliações menos qualitativas ou fundamentadas em percepções, compreendendo um conjunto de diferentes técnicas interpretativas que visam descrever e decodificar os componentes de um sistema complexo de significados. Com esse foco o projeto comparou três modelos de avaliação de desempenho de equipes. O primeiro modelo baseado na personalidade do participante, afirma que os resultados das equipes são influenciados pela seleção prévia dos participantes e que as características individuais desses participantes são críticas para o desempenho da equipe. O segundo modelo fundamenta suas afirmações nas relações interconectadas de positividade e negatividade; questionamento e argumentação e atuação em equipe. O terceiro modelo baseado no processo de interação de grupos também avalia as relações que influenciam o alto desempenho de equipes multifuncionais. Os três modelos foram comparados, através de um estudo de caso único em indústria química paulista, medindo-se os resultados de correlação das equipes e as interações entre os participantes das equipes. As metas atingidas pelas equipes foram utilizadas para suportar os resultados das avaliações dos modelos como sistema de avaliação de equipes. Pode-se concluir que houve uma aproximação satisfatória confirmando a influência sugerida pelos modelos avaliados. A comparação entre os três modelos não permitiu afirmar qual dos três modelos é mais eficaz para avaliação de equipes. Entretanto, é possível, sugerir que a combinação de elementos dos três modelos permitirá a construção de um processo eficaz e prático de avaliação de equipes.(AU)

COMPARAÇÃO DE MODELOS DE AVALIAÇÃO DE DESEMPENHO DE EQUIPES MULTIFUNCIONAIS BASEADOS EM CONCEITOS DE INTERAÇÃO DE GRUPOS E FERRAMENTAS DE ANÁLISE COMPORTAMENTAL

Avaliação de desempenho de equipes multifuncionais é um conceito que tem sido abordado mais freqüentemente nas últimas duas décadas. Diversas teorias e conceitos foram desenvolvidos para tornar as avaliações menos qualitativas ou fundamentadas em percepções, compreendendo um conjunto de diferentes técnicas interpretativas que visam descrever e decodificar os componentes de um sistema complexo de significados. Com esse foco o projeto comparou três modelos de avaliação de desempenho de equipes. O primeiro modelo baseado na personalidade do participante, afirma que os resultados das equipes são influenciados pela seleção prévia dos participantes e que as características individuais desses participantes são críticas para o desempenho da equipe. O segundo modelo fundamenta suas afirmações nas relações interconectadas de positividade e negatividade; questionamento e argumentação e atuação em equipe. O terceiro modelo baseado no processo de interação de grupos também avalia as relações que influenciam o alto desempenho de equipes multifuncionais. Os três modelos foram comparados, através de um estudo de caso único em indústria química paulista, medindo-se os resultados de correlação das equipes e as interações entre os participantes das equipes. As metas atingidas pelas equipes foram utilizadas para suportar os resultados das avaliações dos modelos como sistema de avaliação de equipes. Pode-se concluir que houve uma aproximação satisfatória confirmando a influência sugerida pelos modelos avaliados. A comparação entre os três modelos não permitiu afirmar qual dos três modelos é mais eficaz para avaliação de equipes. Entretanto, é possível, sugerir que a combinação de elementos dos três modelos permitirá a construção de um processo eficaz e prático de avaliação de equipes.(AU)

Loss of transformed phenotype in cancer cells by overexpression of the uteroglobin gene

Uteroglobin (UG) is a multifunctional, secreted protein that has receptor-mediated functions. The human UG (hUG) gene is mapped to chromosome 11q12.2–13.1, a region frequently rearranged or deleted in many cancers. Although high levels of hUG expression are characteristic of the mucosal epithelia of many organs, hUG expression is either drastically reduced or totally absent in adenocarcinomas and in viral-transformed epithelial cells derived from the same organs. In agreement with these findings, in an ongoing study to evaluate the effects of aging on UG-knockout mice, 16/16 animals developed malignant tumors, whereas the wild-type littermates (n = 25) remained apparently healthy even after 1½ years. In the present investigation, we sought to determine the effects of induced-expression of hUG in human cancer cells by transfecting several cell lines derived from adenocarcinomas of various organs with an hUG-cDNA construct. We demonstrate that induced hUG expression reverses at least two of the most important characteristics of the transformed phenotype (i.e., anchorage-independent growth on soft agar and extracellular matrix invasion) of only those cancer cells that also express the hUG receptor. Similarly, treatment of the nontransfected, receptor-positive adenocarcinoma cells with purified recombinant hUG yielded identical results. Taken together, these data define receptor-mediated, autocrine and paracrine pathways through which hUG reverses the transformed phenotype of cancer cells and consequently, may have tumor suppressor-like effects.

Extracellular HIV-1 virus protein R causes a large inward current and cell death in cultured hippocampal neurons: Implications for AIDS pathology

The small HIV-1 accessory protein Vpr (virus protein R) is a multifunctional protein that is present in the serum and cerebrospinal fluid of AIDS patients. We previously showed that Vpr can form cation-selective ion channels across planar lipid bilayers, introducing the possibility that, if incorporated into the membranes of living cells, Vpr might form ion channels and consequently perturb the maintained ionic gradient. In this study, we demonstrate, by a variety of approaches, that Vpr added extracellularly to intact cells does indeed form ion channels. We use confocal laser scanning microscopy to examine the subcellular localization of fluorescently labeled Vpr. Plasmalemma depolarization and damage are examined using the anionic potential-sensitive dye bis(1,3-dibutylbarbituric acid) trimethine oxonol and propidium iodide (PI), respectively, and the effect of Vpr on whole-cell current is demonstrated directly by using the patch-clamp technique. We show that recombinant purified extracellular Vpr associates with the plasmalemma of hippocampal neurons to cause a large inward cation current and depolarization of the plasmalemma, eventually resulting in cell death. Thus, we demonstrate a physiological action of extracellular Vpr and present its mechanistic basis. These findings may have important implications for neuropathologies in AIDS patients who possess significant amounts of Vpr in the cerebrospinal fluid.

Xanthine oxidase activity associated with arterial blood pressure in spontaneously hypertensive rats

Recent evidence in vivo indicates that spontaneously hypertensive rats (SHR) exhibit an increase in oxyradical production in and around microvascular endothelium. This study is aimed to examine whether xanthine oxidase plays a role in overproduction of oxidants and thereby may contribute to hypertensive states as a consequence of the increasing microvascular tone. The xanthine oxidase activity in SHR was inhibited by dietary supplement of tungsten (0.7 g/kg) that depletes molybdenum as a cofactor for the enzyme activity as well as by administration of (−)BOF4272 [(−)-8-(3-methoxy-4-phenylsulfinylphenyl)pyrazolo(1,5-α)-1,3,5-triazine-4-monohydrate], a synthetic inhibitor of the enzyme. The characteristic elevation of mean arterial pressure in SHR was normalized by the tungsten diet, whereas Wistar Koto (WKY) rats displayed no significant alteration in the pressure. Multifunctional intravital videomicroscopy in mesentery microvessels with hydroethidine, an oxidant-sensitive fluoroprobe, showed that SHR endothelium exhibited overproduction of oxyradicals that coincided with the elevated arteriolar tone as compared with WKY rats. The tungsten diet significantly repressed these changes toward the levels observed in WKY rats. The activity of oxyradical-producing form of xanthine oxidase in the mesenteric tissue of SHR was ≈3-fold greater than that of WKY rats, and pretreatment with the tungsten diet eliminated detectable levels of the enzyme activity. The inhibitory effects of the tungsten diet on the increasing blood pressure and arteriolar tone in SHR were also reproducible by administration of (−)BOF4272. These results suggest that xanthine oxidase accounts for a putative source of oxyradical generation that is associated with an increasing arteriolar tone in this form of hypertension.

A gene cluster for macrolide antibiotic biosynthesis in Streptomyces venezuelae: Architecture of metabolic diversity

In a survey of microbial systems capable of generating unusual metabolite structural variability, Streptomyces venezuelae ATCC 15439 is notable in its ability to produce two distinct groups of macrolide antibiotics. Methymycin and neomethymycin are derived from the 12-membered ring macrolactone 10-deoxymethynolide, whereas narbomycin and pikromycin are derived from the 14-membered ring macrolactone, narbonolide. This report describes the cloning and characterization of the biosynthetic gene cluster for these antibiotics. Central to the cluster is a polyketide synthase locus (pikA) that encodes a six-module system comprised of four multifunctional proteins, in addition to a type II thioesterase (TEII). Immediately downstream is a set of genes for desosamine biosynthesis (des) and macrolide ring hydroxylation. The study suggests that Pik TEII plays a role in forming a metabolic branch through which polyketides of different chain length are generated, and the glycosyl transferase (encoded by desVII) has the ability to catalyze glycosylation of both the 12- and 14-membered ring macrolactones. Moreover, the pikC-encoded P450 hydroxylase provides yet another layer of structural variability by introducing regiochemical diversity into the macrolide ring systems. The data support the notion that the architecture of the pik gene cluster as well as the unusual substrate specificity of particular enzymes contributes to its ability to generate four macrolide antibiotics.

A role for TFIIH in controlling the activity of early RNA polymerase II elongation complexes

TFIIH is a multifunctional RNA polymerase II transcription factor that possesses DNA-dependent ATPase, DNA helicase, and protein kinase activities. Previous studies have established that TFIIH enters the preinitiation complex and fulfills a critical role in initiation by catalyzing ATP-dependent formation of the open complex prior to synthesis of the first phosphodiester bond of nascent transcripts. In this report, we present direct evidence that TFIIH also controls RNA polymerase II activity at a postinitiation stage of transcription, by preventing premature arrest by very early elongation complexes just prior to their transition to stably elongating complexes. Unexpectedly, we observe that TFIIH is capable of entering the transcription cycle not only during assembly of the preinitiation complex but also after initiation and synthesis of as many as four to six phosphodiester bonds. These findings shed new light on the role of TFIIH in initiation and promoter escape and reveal an unanticipated flexibility in the ability of TFIIH to interact with RNA polymerase II transcription intermediates prior to, during, and immediately after initiation.

Phylogeny of mRNA capping enzymes

The m7GpppN cap structure of eukaryotic mRNA is formed cotranscriptionally by the sequential action of three enzymes: RNA triphosphatase, RNA guanylyltransferase, and RNA (guanine-7)-methyltransferase. A multifunctional polypeptide containing all three active sites is encoded by vaccinia virus. In contrast, fungi and Chlorella virus encode monofunctional guanylyltransferase polypeptides that lack triphosphatase and methyltransferase activities. Transguanylylation is a two-stage reaction involving a covalent enzyme-GMP intermediate. The active site is composed of six protein motifs that are conserved in order and spacing among yeast and DNA virus capping enzymes. We performed a structure–function analysis of the six motifs by targeted mutagenesis of Ceg1, the Saccharomyces cerevisiae guanylyltransferase. Essential acidic, basic, and aromatic functional groups were identified. The structural basis for covalent catalysis was illuminated by comparing the mutational results with the crystal structure of the Chlorella virus capping enzyme. The results also allowed us to identify the capping enzyme of Caenorhabditis elegans. The 573-amino acid nematode protein consists of a C-terminal guanylyltransferase domain, which is homologous to Ceg1 and is strictly conserved with respect to all 16 amino acids that are essential for Ceg1 function, and an N-terminal phosphatase domain that bears no resemblance to the vaccinia triphosphatase domain but, instead, has strong similarity to the superfamily of protein phosphatases that act via a covalent phosphocysteine intermediate.

Leptin and leptin receptor mRNA and protein expression in the murine fetus and placenta

Leptin is a 167-aa protein that is secreted from adipose tissue and is important in the regulation of energy balance. It also functions in hematopoiesis and reproduction. To assess whether leptin is involved in fetal growth and development we have examined the distribution of mRNAs encoding leptin and the leptin receptor (which has at least six splice variants) in the 14.5-day postcoitus mouse fetus and in the placenta using reverse transcription–PCR and in situ hybridization. High levels of gene expression for leptin, the leptin receptor, and the long splice variant of the leptin receptor with an intracellular signaling domain were observed in the placenta, fetal cartilage/bone, and hair follicles. Receptor expression also was detected in the lung, as well as the leptomeninges and choroid plexus of the fetal brain. Western blotting and immunocytochemistry, using specific antibodies, demonstrated the presence of leptin and leptin receptor protein in these tissues. These results suggest that leptin may play a role in the growth and development of the fetus, both through placental and fetal expression of the leptin and leptin receptor genes. In the fetus, leptin may be multifunctional and have both paracrine and endocrine effects.

Protein phosphatase 2A is required for the initiation of chromosomal DNA replication

Protein phosphatase 2A (PP2A) is an abundant, multifunctional serine/threonine-specific phosphatase that stimulates simian virus 40 DNA replication. The question as to whether chromosomal DNA replication also depends on PP2A was addressed by using a cell-free replication system derived from Xenopus laevis eggs. Immunodepletion of PP2A from Xenopus egg extract resulted in strong inhibition of DNA replication. PP2A was required for the initiation of replication but not for the elongation of previously engaged replication forks. Therefore, the initiation of chromosomal DNA replication depends not only on phosphorylation by protein kinases but also on dephosphorylation by PP2A.

The t(8;21) chromosomal translocation in acute myelogenous leukemia modifies intranuclear targeting of the AML1/CBFα2 transcription factor

Targeting of gene regulatory factors to specific intranuclear sites may be critical for the accurate control of gene expression. The acute myelogenous leukemia 8;21 (AML1/ETO) fusion protein is encoded by a rearranged gene created by the ETO chromosomal translocation. This protein lacks the nuclear matrix-targeting signal that directs the AML1 protein to appropriate gene regulatory sites within the nucleus. Here we report that substitution of the chromosome 8-derived ETO protein for the multifunctional C terminus of AML1 precludes targeting of the factor to AML1 subnuclear domains. Instead, the AML1/ETO fusion protein is redirected by the ETO component to alternate nuclear matrix-associated foci. Our results link the ETO chromosomal translocation in AML with modifications in the intranuclear trafficking of the key hematopoietic regulatory factor, AML1. We conclude that misrouting of gene regulatory factors as a consequence of chromosomal translocations is an important characteristic of acute leukemias.

ADP-ribosylation factor and phosphatidic acid levels in Golgi membranes during budding of coatomer-coated vesicles

The finding that ADP-ribosylation factor (ARF) can activate phospholipase D has led to debate as to whether ARF recruits coat proteins through direct binding or indirectly by catalytically increasing phosphatidic acid production. Here we test critical aspects of these hypotheses. We find that Golgi membrane phosphatidic acid levels do not rise—in fact they decline—during cell-free budding reactions. We confirm that the level of membrane-bound ARF can be substantially reduced without compromising coat assembly [Ktistakis, N. T., Brown, H. A., Waters, M. G., Sternweis, P. C. & Roth, M. G. (1996) J. Cell Biol. 134, 295–306], but find that under all conditions, ARF is present on the Golgi membrane in molar excess over bound coatomer. These results do not support the possibility that the activation of coat assembly by ARF is purely catalytic, and they are consistent with ARF forming direct interactions with coatomer. We suggest that ARF, like many other G proteins, is a multifunctional protein with roles in trafficking and phospholipid signaling.

Human fatty acid synthase: Assembling recombinant halves of the fatty acid synthase subunit protein reconstitutes enzyme activity

Our model of the native fatty acid synthase (FAS) depicts it as a dimer of two identical multifunctional proteins (Mr ≈ 272,000) arranged in an antiparallel configuration so that the active Cys-SH of the β-ketoacyl synthase of one subunit (where the acyl group is attached) is juxtaposed within 2 Å of the pantetheinyl-SH of the second subunit (where the malonyl group is bound). This arrangement generates two active centers for fatty acid synthesis and predicts that if we have two appropriate halves of the monomer, we should be able to reconstitute an active fatty acid-synthesizing site. We cloned, expressed, and purified catalytically active thioredoxin (TRX) fusion proteins of the NH2-terminal half of the human FAS subunit protein (TRX-hFAS-dI; residues 1–1,297; Mr ≈ 166) and of the C-terminal half (TRX-hFAS-dII-III; residues 1,296–2,504; Mr ≈ 155). Adding equivalent amounts of TRX-hFAS-dI and TRX-hFAS-dII-III to a reaction mixture containing acetyl-CoA, malonyl-CoA, and NADPH resulted in the synthesis of long-chain fatty acids. The rate of synthesis was dependent upon the presence of both recombinant proteins and reached a constant level when they were present in equivalent amounts, indicating that the reconstitution of an active fatty acid-synthesizing site required the presence of every partial activity associated with the subunit protein. Analyses of the product acids revealed myristate to be the most abundant with small amounts of palmitate and stearate, possibly because of the way the fused recombinant proteins interacted with each other so that the thioesterase hydrolyzed the acyl group in its myristoyl state. The successful reconstitution of the human FAS activity from its domain I and domains II and III fully supports our model for the structure–function relationship of FAS in animal tissues.