Factors associated with needle sharing among Black male injection drug users in Harris County, Texas

Background. Injection drug users (IDUs) are at increased risk for HIV transmission due to unique risk behaviors, such as sharing needles. In Houston, IDUs account for 18% of all HIV/AIDS cases among Black males. ^ Objectives. This analysis compared demographic, behavioral, and psychosocial characteristics of needle sharing and non-sharing IDUs in a population of Black males in Harris County, Texas. ^ Methods. Data used for this analysis were from the second IDU cycle of the National HIV Behavioral Surveillance System. This dataset included a sample of 288 Black male IDUs. Univariate and multivariate statistical analysis were performed to determine statistically significant associations of needle sharing in this population and to create a functional model to inform local HIV prevention programs. ^ Results. Half of the participants in this analysis shared needles in the past 12 months. Compared to non-sharers, sharers were more likely to be homeless (OR=3.70, p<0.01) or arrested in the past year (OR=2.31, p<0.01), inject cocaine (OR=2.07, p<0.01), report male-to-male sex in the past year (OR=6.97, p<0.01), and to exchange sex for money or drugs. Sharers were less likely than non-sharers to graduate high school (OR=0.36, p<0.01), earn $5,000 or more a year (OR=1.15, p=0.05), get needles from a medical source (OR=0.59, p=0.03), and ever test for HIV (OR=0.17, p<0.01). Sharers were more likely to report depressive symptoms (OR=3.49, p<0.01), lower scores on the family support scale (mean difference 0.41, p=0.01) and decision-making confidence scale (mean difference 0.38, p<0.01), and greater risk-taking (mean difference -0.49, p<0.01) than non-sharers. In a multivariable logistic regression, sharers were less likely to have graduated high school (OR=0.33, p<0.01) and have been tested for HIV (OR=0.12, p<0.01) and were more likely to have been arrested in the past year (OR=2.3, p<0.01), get needles from a street source (OR=3.87, p<0.01), report male-to-male sex (OR=7.01, p<0.01), and have depressive symptoms (OR=2.36, p=0.02) and increased risk-taking (OR=1.78, p=0.01). ^ Conclusions. IDUs that shared needles are different from those that did not, reporting lower socioeconomic status, increased sexual and risk behaviors, increased depressive symptoms and increased risk-taking. These findings suggest that intervention programs that also address these demographic, behavioral, and psychosocial factors may be more successful in decreasing needle sharing among this population.^

Shigellosis in Hidalgo County, Texas 2005--2009: A descriptive study

Shigellosis is a communicable disease harbored primarily by humans. The low infective dose, no vaccine availability, and mild or asymptomatic nature of disease has prevented eradication of Shigella in the United States. In addition, the lack of water and sewage infrastructures which normally contribute to the spread of disease in developing countries, for the most part, is a non-issue in the U.S. making surveillance and risk factor identification important prevention and control measures utilized to reduce the incidence rates of Shigellosis.^ The purpose of this study was to describe the Shigellosis disease burden among the Hidalgo County, Texas population during the 2005-2009 study period and compare these findings with national data available. The potential identification and publication of a health disparity in the form of increased Shigellosis rates among Hidalgo County residents when compared to national rates, especially age-specific rates, are intended to generate public health attention and public health action that will address this issue.^ There were 1,007 confirmed Shigellosis cases reported in Hidalgo County, Texas. An overwhelming majority (79%) of the Shigellosis cases during this time frame occurred in children less than ten years of age. Over the age of 10 through the age of 39, females constituted the majority of cases. Age-specific rates for children four years of age and younger were compared to national rates. The rates for Hidalgo County were higher at 9.2 and 1.8 cases for every one case reported nationally in 2005 and 2006, respectively. The total crude rates of Shigellosis were also higher than the rates available from the Foodborne Diseases Active Surveillance Network (FoodNet) of CDC’s Emerging Infections Program from 2005-2009. As a result, compared to the FoodNet surveillance rates, Hidalgo County experienced above average rates of Shigellosis throughout the study period. The majority of cases were identified in young children under the age of ten.^ The information gathered in this analysis could be used to implement and monitor infection control measures such as hand washing education at facilities that tend to the groups identified at higher risk of infection. In addition, the higher burden of disease found in Hidalgo County requires further study to determine if there are factors associated with an increased risk of Shigellosis in this community and other border communities along the U.S.-Mexico border exist.^

Tuberculosis in Texas correctional facilities between 2005--2009

It has been well documented that inmates incarcerated in prisons and correctional facilities exhibit higher incidence and prevalence of mycobacterium tuberculosis (TB) disease than the general population. This has public health implications because correctional systems may serve as reservoirs for TB disease that can lead to TB outbreaks in the facilities or can be spread to the general public once inmates are released. Although Texas has one of the largest correctional systems in both the US and the world, little is known about TB prevalence and incidence among Texas inmates. The purpose of this study was to elucidate the relationship between TB incidence and incarceration in Texas correctional facilities and investigate differences in various demographic factors. ^ The study used the national TB database from the US Centers for Disease Control and Prevention (CDC) to calculate and compare the overall incidences of TB disease among correctional facility inmates and similar non-inmates in Texas during 2005–2009. Data were also stratified by age, gender, race/ethnicity, birth status, and HIV status and compared between inmates and non-inmates using chi-squared analysis and relative risks with 95% confidence intervals to assess any significant differences. ^ Results suggest that the overall TB incidence among Texas correctional facility inmates per year (88.6 per 100,000) was significantly higher than that of Texas non-inmates (6.3 per 100,000); a 14 fold difference. Relative risk analyses by gender, race/ethnicity, and those with HIV infection found that the TB incidences for all these demographics were significantly and consistently higher in inmates compared to non-inmates. In particular, Hispanic inmates were more likely to develop TB than their non-inmate counterparts by a relative risk of 23.9 (95% CI 19.4–29.4). Likewise, both male and female inmates were more likely to develop TB than non-inmates (RR = 10.2, 95% CI 8.5–12.2; RR = 20.8, 95% CI 12.2–25.3, respectively), although female inmates unconventionally exhibited a higher TB incidence and relative risk than males inmates, which has not been shown. Among those with HIV infections, correctional facility inmates were 2.6 times were likely to develop TB disease than non-inmates (95% CI 1.5–4.4). ^ Inmates in Texas correctional facilities have a higher incidence of TB than non-inmates. Part of this higher risk may be because a large proportion of inmates come from populations already at high risks for TB, such as foreign born immigrants, those infected with HIV, and low SES groups such as many racial/ethnic minorities. Thus, these results may be used as a basis for more controlled and detailed research in the area, and to further characterize incarceration as a risk factor for TB incidence. They may also bring much needed attention about this health disparity to public health officials, legislators, and health administrators to expand and improve TB control in Texas correctional facilities, particularly among inmates released to the community, and reduce the risk of TB transmission to the general population.^

Functional studies of a LIM -homeodomain transcription factor lmx1b in murine mid -hindbrain and limb development

This thesis is centered on applying molecular genetics to study pattern formation during animal development. More specifically, this thesis describes the functional studies of a LIM-homeodomain gene called lmx1b during murine embryogenesis. Lmx1b expression is restricted to the mid-hindbrain junction as well as to the dorsal mesenchyme of the limb, suggesting important functions during mid-hindbrain and limb development. To test these possibilities, lmx1b homozygous mutant mice were generated and their limb and CNS phenotypes examined. Lmx1b homozygous mutant mice exhibit a large reduction of mid-hindbrain structures, and that their limbs are symmetrical along the dorsal-ventral axis as the result of a dorsal to ventral transformation. Taken together, these studies define essential functions for lmx1b in mid-hindbrain patteming and in dorsal limb cell fate determination. However, the molecular mechanisms which accounts for these phenotypes are unknown, and whether lmx1b has same or distinctive functions during the mid-hindbrain and limb development is also unclear. ^ Recently, insight into molecular mechanisms of mid-hindbrain patterning and limb development has resulted from the identification of several factors with restricted expression patterns within these regions. These include the secreted factors wnt-1, fgf-8, wnt-7a and the transcription factors pax-2, and en-1. Targeted disruption of any of these genes in mice suggests that these genes might be involved in similar regulatory pathways. Analysis of the expression of these genes in lmx1b mutants demonstrates that lmxlb is not required for the initiation, but is required to maintain their expression at the mid-hindbrain junction. Thus, lmxlb is not required for specifying mid-hindbrain cell fates, rather, it functions to ensure the establishment or maintenance of a proper organizing center at the mid-hindbrain junction. Interestingly, lmxlb functions cell non-autonomously in chimera analysis, which indicates that lmx1b might regulate the expression of secreted factors such as wnt-1 and/or fgf-8 in the organizing center. In contrast, lmx1b functions cell autonomously in the dorsal limb to govern dorsal ventral limb development and its expression is regulated by with wnt-7a and en-1. However, single and double mutant analysis suggest that all three genes have partially overlapping functions as well as independent functions. The results point toward a complicated network of cross-talks among all three limb axes. ^

La cultura en el desarrollo económico local : una aplicación en el Museo de Antioquia (Medellín , Colombia)

La cultura se presenta hoy como un elemento determinante en la planificación del desarrollo, tanto por los efectos económicos que genera en términos de empleo, ingresos, y producción; como por ser un instrumento útil y eficaz para el fortalecimiento de la independencia, la soberanía y la identidad de los territorios en un mundo globalizado. El objetivo de este estudio es reconocer el impacto de la cultura en el desarrollo económico a través de un ejercicio empírico centrado en el Museo de Antioquia de la ciudad de Medellín (Colombia). Se aplicó una encuesta de percepción a los habitantes y visitantes de la ciudad. Los datos se sometieron a un análisis descriptivo y se formalizó un Modelo de Regresión Logística en busca de identificar y explicar los elementos que permiten vincular la cultura y el desarrollo. Se encontró que cerca al 90% de los encuestados afirmaron que la existencia del Museo de Antioquia es importante para el desarrollo económico de la ciudad de Medellín, identificándolo como un atractivo turístico y cultural que genera impactos positivos en el crecimiento económico y el bienestar social.

Model-based changes in global annual mean surface temperature change (Delta T_g) and radiative forcing due to land ice albedo changes (Delta R_[LI]) over the last 5 Myr, supplementary material

It is still an open question how equilibrium warming in response to increasing radiative forcing - the specific equilibrium climate sensitivity S - depends on background climate. We here present palaeodata-based evidence on the state dependency of S, by using CO2 proxy data together with a 3-D ice-sheet-model-based reconstruction of land ice albedo over the last 5 million years (Myr). We find that the land ice albedo forcing depends non-linearly on the background climate, while any non-linearity of CO2 radiative forcing depends on the CO2 data set used. This non-linearity has not, so far, been accounted for in similar approaches due to previously more simplistic approximations, in which land ice albedo radiative forcing was a linear function of sea level change. The latitudinal dependency of ice-sheet area changes is important for the non-linearity between land ice albedo and sea level. In our set-up, in which the radiative forcing of CO2 and of the land ice albedo (LI) is combined, we find a state dependence in the calculated specific equilibrium climate sensitivity, S[CO2,LI], for most of the Pleistocene (last 2.1 Myr). During Pleistocene intermediate glaciated climates and interglacial periods, S[CO2,LI] is on average ~ 45 % larger than during Pleistocene full glacial conditions. In the Pliocene part of our analysis (2.6-5 Myr BP) the CO2 data uncertainties prevent a well-supported calculation for S[CO2,LI], but our analysis suggests that during times without a large land ice area in the Northern Hemisphere (e.g. before 2.82 Myr BP), the specific equilibrium climate sensitivity, S[CO2,LI], was smaller than during interglacials of the Pleistocene. We thus find support for a previously proposed state change in the climate system with the widespread appearance of northern hemispheric ice sheets. This study points for the first time to a so far overlooked non-linearity in the land ice albedo radiative forcing, which is important for similar palaeodata-based approaches to calculate climate sensitivity. However, the implications of this study for a suggested warming under CO2 doubling are not yet entirely clear since the details of necessary corrections for other slow feedbacks are not fully known and the uncertainties that exist in the ice-sheet simulations and global temperature reconstructions are large.

Las bibliotecas públicas como instituciones de integración social : Un estudio de caso en la Biblioteca Pública La Peña de BibloRed, en Bogotá (Colombia)

La investigación se propuso abordar cómo las bibliotecas públicas en contextos populares pueden agenciar procesos de subjetividad colectiva a partir de sus servicios bibliotecarios. Se plantea un análisis sobre estas bibliotecas como agencias de construcción de la esfera pública, mediante un estudio de caso en una biblioteca pública-popular en Bogotá, Colombia. Se propone inicialmente ilustrar cómo ha sido la forma en que la bibliotecología ha abordado la pregunta sobre ¿Qué es una biblioteca pública y cuál es su papel social y político?, identificando las razones por las que consideramos que se hacen necesarias indagaciones desde las ciencias sociales. Luego, haciendo un repaso sobre las teorías de la subjetividad y la subjetividad colectiva, se construye alrededor de la categoría de subjetividad colectiva un instrumento para la indagación de corte cualitativo, que permite explorar en las narrativas subjetivas de los usuarios, elementos para describir procesos agenciados desde la biblioteca pública escogida. Por último, se presentan las consideraciones finales sobre las bibliotecas públicas como agencias de procesos socioculturales que intervienen como escenarios de formación y participación

Las bibliotecas públicas como instituciones de integración social : Un estudio de caso en la Biblioteca Pública La Peña de BibloRed, en Bogotá (Colombia)

La investigación se propuso abordar cómo las bibliotecas públicas en contextos populares pueden agenciar procesos de subjetividad colectiva a partir de sus servicios bibliotecarios. Se plantea un análisis sobre estas bibliotecas como agencias de construcción de la esfera pública, mediante un estudio de caso en una biblioteca pública-popular en Bogotá, Colombia. Se propone inicialmente ilustrar cómo ha sido la forma en que la bibliotecología ha abordado la pregunta sobre ¿Qué es una biblioteca pública y cuál es su papel social y político?, identificando las razones por las que consideramos que se hacen necesarias indagaciones desde las ciencias sociales. Luego, haciendo un repaso sobre las teorías de la subjetividad y la subjetividad colectiva, se construye alrededor de la categoría de subjetividad colectiva un instrumento para la indagación de corte cualitativo, que permite explorar en las narrativas subjetivas de los usuarios, elementos para describir procesos agenciados desde la biblioteca pública escogida. Por último, se presentan las consideraciones finales sobre las bibliotecas públicas como agencias de procesos socioculturales que intervienen como escenarios de formación y participación

Adenosine triphosphate concentrations and microplankton biomass in sea water of the Peru upwelling region

ATP distribution in coastal waters off Peru was examined and was found to differ with hydrological conditions in this area; maximal values in the vicinity of an intense upwelling were the same in 1974 and 1978. ATP distribution was highly non-uniform in 1978, particularly in upper layers of the northern section, due to disruption of a community (dense patches of bloom), which began about 10-15 days before our observations, and also because of appearance of a red tide. Unusually intense microplankton metabolism was found in Peruvian waters, particularly in the lower layers of the northern section, where ATP concentration of 3.6 ?g/l were found. Values of live microplankton biomass presented.

Las bibliotecas públicas como instituciones de integración social : Un estudio de caso en la Biblioteca Pública La Peña de BibloRed, en Bogotá (Colombia)

La investigación se propuso abordar cómo las bibliotecas públicas en contextos populares pueden agenciar procesos de subjetividad colectiva a partir de sus servicios bibliotecarios. Se plantea un análisis sobre estas bibliotecas como agencias de construcción de la esfera pública, mediante un estudio de caso en una biblioteca pública-popular en Bogotá, Colombia. Se propone inicialmente ilustrar cómo ha sido la forma en que la bibliotecología ha abordado la pregunta sobre ¿Qué es una biblioteca pública y cuál es su papel social y político?, identificando las razones por las que consideramos que se hacen necesarias indagaciones desde las ciencias sociales. Luego, haciendo un repaso sobre las teorías de la subjetividad y la subjetividad colectiva, se construye alrededor de la categoría de subjetividad colectiva un instrumento para la indagación de corte cualitativo, que permite explorar en las narrativas subjetivas de los usuarios, elementos para describir procesos agenciados desde la biblioteca pública escogida. Por último, se presentan las consideraciones finales sobre las bibliotecas públicas como agencias de procesos socioculturales que intervienen como escenarios de formación y participación

Ecological investigations in the wadden area off Borkum, East Frisian Islands, Germany

Die Bodentiergemeinschaft des Wattenmeeres ist von Frühjahr bis Herbst eines jeden Jahres durch extrem hohe Dichten von Jungtieren charakterisiert. Die Kenntnisse über die Ansiedlung von fplanktischen Larven im Wattenmeer, sowie die Dynamik postlarvaler Stadien sind aufgrund der üblicherweise verwendeten, großen Siebmaschenweiten gering. Gerade aber diesen Altersstadien kommt möglicherweise eine besondere Stellung im Energiefluß des Wattenmeeres zu. An 5 Stationen (von NWL bis HWL, B1-B5) im Rückseitenwatt der ostfriesischen Insel Borkum wurden 1986 Ansiedlung, räumliche Verteilung, Wachstum, Mortalität und Produktion der Altersklasse 0 von Macoma balthica, Mya arenaria und Cerastoderma edule untersucht. Um die Ansiedlung der planktotrophen Larven dieser Arten zu beschreiben, wurden ihre Dichten in Plankton und Bodenproben miteinander verglichen. Die Untersuchungen zur Dynamik der benthischen Stadien wurden mit zwei in der Probenfläche und der Siebmaschenweite unterschiedlichen Probenserien durchgeführt. Die Drift postlarvaler Stadien wurde durch bodennahe Planktonfänge innerhalb des Eulitorals nachgewiesen. Parallel zu den Untersuchungen an der Endofauna wurden das Vorkommen und die Größe epibenthischer Räuber im Untersuchungsgebiet erfaßt. Die Hauptansiedlung von M. balthica- und M. arenaria-Larven erfolgte nahezu gleichzeitig Ende Mai/Anfang Juni. Die meisten Larven beider Arten gingen an der prielnächsten (tiefsten) Station (B1) zum Bodenleben über, gefolgt von der nächst höher gelegenen Station B2. Während frühe Bodenstadien von M. arenaria nicht im oberen Bereich des Watts (B3,B4) gefunden wurden, ist eine geringfügige Erstansiedlung von M. balthica in diesem Gebiet nicht auszuschließen. Ein die Ansiedlung limitierender Einfluß der relativ dichten Mya arenaria-Siedlung an den Stationen B1 und B2 sowie der Alttiere von M. balthica konnte nicht festgestellt werden. Die Ähnlichkeit des Ansiedlungsprozesses bei beiden Arten, die sich im Zahlenverhältnis Larvenangebot zu Anzahl der ersten Bodenstadien widerspiegelt, kann ein Hinweis auf eine überwiegend passive Ansiedlung der Larven am Boden sein. Der Ort der Hauptansiedlung von C. edule wurde durch den Transekt nicht erfaßt. Die Station B2 war zwar durch ein Herzmuschelfeld charakterisiert, dieses war aber nach zwei Eiswintern nahezu vollständig eliminiert. Der Abundanz der planktischen Larven zufolge war der Hauptansiedlungszeitraum ebenfalls Ende Mai/Anfang Juni. Zu dieser Zeit wurden nur vereinzelt frühe Bodenstadien an den Stationen B1 und B2 gefunden, keine an den Stationen B3 und B4. Während die frühen postlarvalen Stadien von M. arenaria überwiegend am Ort der Ansiedlung blieben, verbreiteten sich die von M. balthica bis in den oberen Bereich des Untersuchungsgebietes (B3-B5). Analog zu der Besiedlung dieser Gebiete durch postlarvale M. balthica wurde die im Verlauf des Untersuchungsjahres stattfindende Kolonisierung der Station B1 durch C. edule ebenfalls postlarvalem Transport zugeschrieben. Demzufolge spielt bei beiden Muschelarten postlarvaler Transport eine wichtige Rolle bei der Besiedlung von Habitaten. Planktonfänge innerhalb der bodennahen Wasserschicht bestätigten, daß im Untersuchungsgebiet M. balthica die am stärksten verdriftende Muschelart war, gefolgt von C. edule. Mortalität, Wachstum, mittlere Biomasse, Produktion und P/B-Verhältnis wurden für M. balthica an den Stationen B1, B3 und B4 sowie für M. arenaria an der Station B1 bestimmt. Wachstum und damit auch Produktion beider Arten erwiesen sich hier - wie an den höher gelegen Stationen (nur M. balthica) - als durch größenselektiven Feinddruck beeinflußt. Der Effekt postlarvalen Transports auf Wachstum wird diskutiert. Übergreifend über die auf Artebene diskutierten Ergebnisse wird die Bedeutung der Dispersion postlarvaler Stadien und die Wirkung epibenthischen Feinddrucks im Wattenmeer erörtert. Der Vergleich postlarvalen Transportes mit der Dispersion planktischer Larvenstadien, der Dispersion von Meiofauna und der Mobilität adulter Stadien der Makrofauna verdeutlicht, daß es sich hierbei um eine Strategie handeln kann, innerhalb eines unvorhersagbaren Biotops freiwerdende Ressourcen zu nutzen und dadurch Konkurrenz zu vermeiden. Es wird die Hypothese aufgestellt, daß Initialansiedlung und Immigration einerseits sowie Feinddruck und Emigration andererseits einen Regelkreis darstellen, der in verschiedenen Teilbereichen des Watts mit unterschiedlicher Geschwindigkeit abläuft.

Pollen record in the area of Niederrheinische Bucht, Germany

Die Niederrheinische Bucht, ein altes tektonisches Senkungsgebiet, dessen Ausdehnung durch die Orte Aachen, Bonn, Duüsseldorf und Duisburg bestimmt ist, bildete während des jüngeren Tertiärs eine Meeresbucht am Südrande des Nordseebeckens. Noch zu Beginn des Pleistocäns erstreckte sich die Nordsee bis in den Raum von Nijmegen, und im Pliocän verlief die Kuüste etwa auf der Linie Maastricht-Kleve. Im Mittelmiocän reichte die Nordsee bis in die nördliche Niederrheinische Bucht. Marines Oberoligocän mit reicher Fauna findet sich noch in der Gegend von Köln. In Verbindung mit den marinen Transgressionen kam es in den inneren Teilen der Niederrheinischen Bucht zu mehr oder weniger ausgedehnten Vermoorungen, die zur Bildung von Braunkohlenflözen führten, unter denen das miocäne Hauptbraunkohlenflöz nordwestlich von Köln eine Mächtigkeit von mehr als 90 m erreicht. Nach NW spaltet sich das Hauptflöz in drei Teilflöze auf, die von oben nach unten als Flöz Garzweiler, Flöz Frimmersdorf und Flöz Morken bezeichnet werden. Diese Flöze können, wie neue Untersuchungen ergaben, eindeutig mit dem marinen Mittelmiocän in Verbindung gebracht werden.

Development of land rental market and its effect on household farming in rural China : an empirical study in Zhejiang Province

This paper investigates the impact of land rental market development on the efficiency of labor allocation and land utilization in rural China. To test the hypothesis that the shadow wage of a rent-in household with limited off-farm opportunities will increase with the development of a land rental market for households, a statistical comparison between the shadow wage and the estimated market wage was conducted. The results showed that the shadow wage for both rent-in households and non-rent-in households was significantly lower than the market wage, but that the wage for the rent-in households was statistically higher than that for non-rent-in households in Fenghua and Deqing, the two counties surveyed in this study. In addition, the estimated marginal product of farmland for rent-in households was statistically higher than the actual land rent that those households paid, while a null hypothesis that the actual rental fee accepted by rent-out households is equivalent to the marginal product of farmland for those households was not rejected in Fenghua county where land transactions by mutual agreement were more prevalent. These results indicate that the development of the land rental market facilitates the efficiency of labor allocation and farmland utilization in rural China.

Aplicaciones estructurales de la guadua (Guadua angustifolia Kunth): Proyecto de estructura modular multifuncional en Colombia

La Guadua (Guadua angustifolia Kunth) es una de las especies forestales más características de Colombia. Perteneciente a la familia del bambú, ésta planta nativa de Colombia usada en la construcción permite una reducción de costos, garantizados, entre otras ventajas, por sus propiedades físico-mecánicas de flexibilidad, resistencia, dureza, efecto climatizado y sismo resistencia. En el proyecto se plantea inicialmente un estudio de la Guadua como material estructural. Se estudiará su anatomía, sus propiedades físicas y mecánicas así como la normativa existente que rige su uso en construcción y por último se darán algunos ejemplos en los que se puede comprobar su uso en la actualidad. Posteriormente se procederá al desarrollo del proyecto cuya finalidad es el diseño de una estructura modular multifuncional que se necesita para llevarla a cabo en un proyecto de cooperación localizado en Neiva (Colombia). El proyecto incluirá todos los documentos necesarios para un trabajo de estas características: memoria, pliego de condiciones técnicas, presupuesto, planos, así como el Estudio de Seguridad y Salud Laboral. Como solución a las necesidades planteadas en el proyecto de cooperación, se realizará el diseño de dos estructuras modulares cuya finalidad sea las de uso como oficina y como almacén. Se aplicará para su cálculo el CTE cómo normativa de construcción, pero apoyándose en algunos parámetros en la NSR-10, estableciendo una comparativa posterior entre ambas normativas. Debido a la importancia de la acción sísmica en Colombia se comprobará la resistencia sísmica del módulo diseñado según el “Manual de Construcción, evaluación y rehabilitación sismo resistente de viviendas de mampostería” creado por la Asociación Colombiana de Ingeniería Sísmica. Basándose en este manual se definirán los tipos de uniones más favorables sísmicamente de los módulos con el diseño de una cercha auxiliar necesaria según el tipo de unión. ABSTRACT PROJECT: Structural applications of the guadua (Guadua angustifolia Kunth). Project of modular multifunctional structure in Colombia Guadua (Guadua angustifolia Kunth) is one of the forest species more characteristics of Colombia. Pertaining to the family of the bamboo, this one native plant of Colombia used in the construction allows a reduction of costs, guaranteed, among others advantages, by its physic mechanical properties of flexibility, resistance, hardness, climatic effect and earthquake resistance. The project initially considers a study of the Guadua as structural material. We will study its anatomy, its physical and mechanical properties as well as the existing norm that governs its use in construction and finally some examples will be provided in which its actual use can be verified. Later on, we will proceed with the development of the project which purpose is the design of a multifunctional modular structure required to in a project of cooperation located in Neiva (Colombia). The project will include all the necessary documents for a work of these characteristics: memory, technical specifications, budget, drawings, as well as the Security and Labor Health Study. In order to satisfy the needs raised in the cooperation project, we will undertake the design of two modular structures with the purpose to be used as office and warehouse. The construction normative CTE will be applied for its calculation, but some parameters will be based in the NSR-10, establishing a comparison between both norms. Due to the importance of the seismic action in Colombia, the seismic resistance of the module will be verified according to the “Manual of Construction, evaluation and rehabilitation resistant earthquake of rubblework houses” created by the Colombian Association of Seismic Engineering,. We will also use this Manual to define the types of unions more favorable from seismic point of view, designing the required auxiliary segments according to the type of union.

Nonlinear description of transversal motion in a laminar boundary layer with streaks

The nonlinear streamwise growth of a spanwise periodic array of steady streaks in a flat plate boundary layer is numerically computed using the well known Reduced Navier-Stokes formulation. It is found that the flow configuration changes substantially when the amplitude of the streaks grows and the nonlinear effects come into play. The transversal motion (in the wall normal-spanwise plane), which is normally not considered, becomes non-negligible in the nonlinear regime, and it strongly distorts the streamwise velocity profiles, which end up being quite different from those predicted by the linear theory. We analyze in detail the resulting flow patterns for the nonlinearly saturated streaks, and compare them with available experimental results.