939 resultados para Build-Up Back To Back LSB, Cold-Formed Steel Structures, Lateral Distortional Buckling
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Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia - UL
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The need for solutions to minimize the negative environmental impacts of anthropogenic activities Fhas increased. Sewage sludge is composed of predominantly organic matter and can be used to improve soil characteristics, such as fertility. Therefore, its application in agriculture is an adequate alternative for its final disposal. However, there is a lack of information on its long-term effects on soil changes in tropical areas. Thus, the objectives of this study were to determine (i) the effect of sewage sludge application on heavy metal build-up in soil and maize grains and leaves, and (ii) the effects of soil amendment with sewage sludge on the chemical properties of a Brazilian oxisol. Besides the increasing levels of Zn, Cu, Ni, and Cr, amending soil with sewage sludge also alters the distribution of these metals by increasing the mobile Phases, which correlated significantly with the increase in metal extraction with two single extractants, Mehlich 1 and DTPA (Diethylene triamine pentaacetic acid). The levels of Fe, Mn, Zn, and Cu in maize grains and leaves increased with the type and rate of sewage sludge application. Nevertheless, metal build-up in soil and plants was within the allowed limits. Significant differences were also found in soil characteristics like humic fractionation with the applied sewage doses. The data obtained does not indicate any expressive drawbacks in the use of sewage sludge as a soil amendment, as the heavy metal concentrations observed are unlikely to cause any environmental or health problems, even overestimated loadings, and are in accordance with the Brazilian regulations on farming land biosolid disposal.
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In this work, we describe the growth of NaCl crystals by evaporating droplets of aqueous solution while monitoring them with infrared thermography. Over the course of the evaporation experiments, variations in the recorded signal were observed and interpreted as being the result of evaporation and crystallisation. In particular, we observed sharp and transient decreases in the thermosignal during the later stages of high-concentration drop evaporation. The number of such events per experiment, referred to as “pop-cold events”, varied from 1 to over 100 and had durations from 1 to 15 s. These events are interpreted as a consequence from the top-supplied creeping (TSC) of the solution feeding the growth of efflorescence-like crystals. This phenomenon occurred when the solution was no longer macroscopically visible. In this case, efflorescence-like crystals with a spherulite shape grew around previously formed cubic crystals. Other crystal morphologies were also observed but were likely fed by mass diffusion or bottom-supplied creeping (BSC) and were not associated with “pop-cold events”; these morphologies included the cubic crystals at the centre, ring-shaped at the edge of droplets and fan-shaped crystals. After complete evaporation, an analysis of the numbers and sizes of the different types of crystals was performed using image processing. Clear differences in their sizes and distribution were observed in relation to the salt concentration. Infrared thermography permitted a level of quantification that previously was only possible using other techniques. As example, the intermittent efflorescence growth process was clearly observed and measured for the first time using infrared thermography.
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El Estribo Volcanic Complex (EVC) is located in the northern part of the Michoacán–Guanajuato Volcanic Field within the Trans-Mexican Volcanic Belt (TMVB). El Estribo is located at the southern edge of the E-W Pátzcuaro fault that belongs to the Pátzcuaro-Jarácuaro graben, a western extension of the E-W Morelia–Acambay fault system. Stratigraphy, geochronology, chemistry, and mineral assemblages suggest that the volcanic complex was constructed in two periods separated by a ~ 100 ka volcanic hiatus: a) emission of lava flows that constructed a shield volcano between 126 ka, and b) mixed phreatomagmatic to Strombolian activity that formed a cinder cone ~ 28 ka. The magmas that fed these monogenetic volcanoes were able to use the same feeding system. The cinder cone itself was constructed by Strombolian fallouts and remobilized scoria beds, followed by an erosion period, and by a mixed phreatomagmatic to magmatic phase (Strombolian fallouts ending with lava flows). Soft-sedimentary deformation of beds and impact sags, cross-bedding, as well as pitting and hydrothermal cracks found in particles support the phreatomagmatic phase. The erupted magmas through time ejected basaltic andesitic lava flows (56.21–58.88% SiO2) that built the shield volcano and then basaltic andesitic scoria (57.65–59.05% SiO2) that constructed the cinder cone. Although they used the same feeding system, the geochemical data and the mineral chemistry of the magmas indicate that the shield volcano and the cinder cone were fed by different magma batches erupted thousands of years apart. Therefore, the location of El Estribo Volcanic Complex along an E-W fault that has generated two sector collapses of the shield volcano to the north may be directly linked to this complex redistribution of the magmatic paths to the surface. Our findings show that magmatic feeding systems within monogenetic volcanic fields could be long lived, questioning the classic view of the monogenetic nature of their volcanoes and yielding information about the potential volcanic risk of these settings, usually considered risk-free.
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Safety in civil aviation is increasingly important due to the increase in flight routes and their more challenging nature. Like other important systems in aircraft, fuel level monitoring is always a technical challenge. The most frequently used level sensors in aircraft fuel systems are based on capacitive, ultrasonic and electric techniques, however they suffer from intrinsic safety concerns in explosive environments combined with issues relating to reliability and maintainability. In the last few years, optical fiber liquid level sensors (OFLLSs) have been reported to be safe and reliable and present many advantages for aircraft fuel measurement. Different OFLLSs have been developed, such as the pressure type, float type, optical radar type, TIR type and side-leaking type. Amongst these, many types of OFLLSs based on fiber gratings have been demonstrated. However, these sensors have not been commercialized because they exhibit some drawbacks: low sensitivity, limited range, long-term instability, or limited resolution. In addition, any sensors that involve direct interaction of the optical field with the fuel (either by launching light into the fuel tank or via the evanescent field of a fiber-guided mode) must be able to cope with the potential build up of contamination-often bacterial-on the optical surface. In this paper, a fuel level sensor based on microstructured polymer optical fiber Bragg gratings (mPOFBGs), including poly (methyl methacrylate) (PMMA) and TOPAS fibers, embedded in diaphragms is investigated in detail. The mPOFBGs are embedded in two different types of diaphragms and their performance is investigated with aviation fuel for the first time, in contrast to our previous works, where water was used. Our new system exhibits a high performance when compared with other previously published in the literature, making it a potentially useful tool for aircraft fuel monitoring.
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Recommender systems (RS) are used by many social networking applications and online e-commercial services. Collaborative filtering (CF) is one of the most popular approaches used for RS. However traditional CF approach suffers from sparsity and cold start problems. In this paper, we propose a hybrid recommendation model to address the cold start problem, which explores the item content features learned from a deep learning neural network and applies them to the timeSVD++ CF model. Extensive experiments are run on a large Netflix rating dataset for movies. Experiment results show that the proposed hybrid recommendation model provides a good prediction for cold start items, and performs better than four existing recommendation models for rating of non-cold start items.
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The burden of foodborne disease has large economic and social consequences worldwide. Despite strict regulations, a number of pathogens persist within the food environment, which is greatly contributed to by a build-up of resistance mechanisms and also through the formation of biofilms. Biofilms have been shown to be highly resistant to a number of antimicrobials and can be extremely difficult to remove once they are established. In parallel, the growing concern of consumers regarding the use of chemically derived antimicrobials within food has led to a drive toward more natural products. As a consequence, the use of naturally derived antimicrobials has become of particular interest. In this study we investigated the efficacy of nisin A and its bioengineered derivative M21A in combination with food grade additives to treat biofilms of a representative foodborne disease isolate of Listeria monocytogenes. Investigations revealed the enhanced antimicrobial effects, in liquid culture, of M21A in combination with citric acid or cinnamaldehyde over its wild type nisin A counterpart. Subsequently, an investigation was conducted into the effects of these combinations on an established biofilm of the same strain. Nisin M21A (0.1 μg/ml) alone or in combination with cinnamaldehyde (35 μg/ml) or citric acid (175 μg/ml) performed significantly better than combinations involving nisin A. All combinations of M21A with either citric acid or cinnamaldehyde eradicated the L. monocytogenes biofilm (in relation to a non-biofilm control). We conclude that M21A in combination with available food additives could further enhance the antimicrobial treatment of biofilms within the food industry, simply by substituting nisin A with M21A in current commercial products such as Nisaplin® (Danisco, DuPont).
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First year follow-up after heart transplantation requires invasive tests. Although patients used to be hospitalized for this purpose, ambulatory invasive procedures now offer the possibility of outpatient follow-up. The feasibility and security of this strategy is unknown. From 2007 we transitioned to outpatient follow-up. We have retrospectively reviewed the clinical course of the outpatient group (2007 to 2014) and an inpatient group (2000–2006). Basal characteristics, hospital stay, infections, rejection episodes and vascular complications were evaluated. 87 patients had Inpatient Follow-up (IF) and 98 Outpatient Follow-up (OF). Basal characteristics were similar, with significant differences in immunosuppression (tacrolimus IF 44.8% vs. OF 90.8%, and mycophenolate IF 86.2% vs OF 100%, both p values < 0.001) and age (IF 52 ± 11.5 years vs. OF 56.1 ± 11 years, p = 0.016). In the OF group more clinical visits were performed (IF 10 vs. OF 13, p < 0.001) while hospital stay was lower (IF 23 days vs. OF 3 days, p < 0.001). The rate of infection, rejection, and vascular complications was similar. No difference was found in 1-year mortality (IF 2.3% vs. 1.0%, p = 0.60). First year post-cardiac transplantation outpatient follow-up seems to be feasible and safe in terms of infection, rejection, vascular complications and mortality.
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First year follow-up after heart transplantation requires invasive tests. Although patients used to be hospitalized for this purpose, ambulatory invasive procedures now offer the possibility of outpatient follow-up. The feasibility and security of this strategy is unknown. From 2007 we transitioned to outpatient follow-up. We have retrospectively reviewed the clinical course of the outpatient group (2007 to 2014) and an inpatient group (2000–2006). Basal characteristics, hospital stay, infections, rejection episodes and vascular complications were evaluated. 87 patients had Inpatient Follow-up (IF) and 98 Outpatient Follow-up (OF). Basal characteristics were similar, with significant differences in immunosuppression (tacrolimus IF 44.8% vs. OF 90.8%, and mycophenolate IF 86.2% vs OF 100%, both p values < 0.001) and age (IF 52 ± 11.5 years vs. OF 56.1 ± 11 years, p = 0.016). In the OF group more clinical visits were performed (IF 10 vs. OF 13, p < 0.001) while hospital stay was lower (IF 23 days vs. OF 3 days, p < 0.001). The rate of infection, rejection, and vascular complications was similar. No difference was found in 1-year mortality (IF 2.3% vs. 1.0%, p = 0.60). First year post-cardiac transplantation outpatient follow-up seems to be feasible and safe in terms of infection, rejection, vascular complications and mortality.
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Shared management between businesses, governments and society in the historic town of São Paulo city began concurrently with the growth of nonprofit organizations (NGOs) in the 1990s. The program Ações Locais, coordinated by the NGO Associação Viva o Centro is housed in this context and its mission is to bring together individuals, businesses and local governments for economic, social and political development as to build up the citizenship in that area. This study provides a historical background on formation of Brazilian citizenship and, from that reference, analyzes the performing citizenship in the program Ações Locais. The main conclusion of the analysis identified that the program have been consolidated, despite the enormous quotidian difficulties, especially in the social inclusion actions for the poor. The dilemma about how bring in the excluded segments of the population may indicate a new field of research and future studies.
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The ability to measure tiny variations in the local gravitational acceleration allows – amongst other applications – the detection of hidden hydrocarbon reserves, magma build-up before volcanic eruptions, and subterranean tunnels. Several technologies are available that achieve the sensitivities required (tens of μGal/√Hz), and stabilities required (periods of days to weeks) for such applications: free-fall gravimeters, spring-based gravimeters, superconducting gravimeters, and atom interferometers. All of these devices can observe the Earth tides; the elastic deformation of the Earth’s crust as a result of tidal forces. This is a universally predictable gravitational signal that requires both high sensitivity and high stability over timescales of several days to measure. All present gravimeters, however, have limitations of excessive cost (£70 k) and high mass (<8 kg). In this thesis, the building of a microelectromechanical system (MEMS) gravimeter with a sensitivity of 40 μGal/√Hz in a package size of only a few cubic centimetres is discussed. MEMS accelerometers – found in most smart phones – can be mass-produced remarkably cheaply, but most are not sensitive enough, and none have been stable enough to be called a ‘gravimeter’. The remarkable stability and sensitivity of the device is demonstrated with a measurement of the Earth tides. Such a measurement has never been undertaken with a MEMS device, and proves the long term stability of the instrument compared to any other MEMS device, making it the first MEMS accelerometer that can be classed as a gravimeter. This heralds a transformative step in MEMS accelerometer technology. Due to their small size and low cost, MEMS gravimeters could create a new paradigm in gravity mapping: exploration surveys could be carried out with drones instead of low-flying aircraft; they could be used for distributed land surveys in exploration settings, for the monitoring of volcanoes; or built into multi-pixel density contrast imaging arrays.
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Las Mipymes son un componente fundamental para el desarrollo económico y social de cualquier país, en especial de un país como Colombia en donde representan el 99,9% de las empresas actualmente constituidas, concentrando el 81% de los empleados a nivel nacional (Fedesarrollo, 2013). Aunque juegan un papel protagónico en la economía colombiana, las Mipymes aún deben recorrer un camino extenso para poder explotar todo el potencial con el que cuentan, puesto que presentan un alto índice de mortandad empresarial en los primeros años de funcionamiento, esto evidenciado en los resultados del estudio GEM (Global Entrepreneurship Monitor, 2009) en donde se encontró que sólo el 12,61% de los negocios lograron superar los 42 meses de permanencia en el mercado (El País, 2010) principalmente a causa de la ausencia de una planeación estratégica de largo plazo que les permita a los negocios emprendedores del país alcanzar la competitividad. Si bien es cierto que crear empresa es relativamente sencillo, son múltiples los retos tanto internos como externos que deben enfrentar las organizaciones para poder alcanzar una etapa de madurez empresarial, sobre todo en los primeros años de funcionamiento que son los más críticos y decisivos para el futuro de cualquier empresa, es por esto que se hace indispensable emplear estrategias que les permitan ser sostenibles a largo plazo, en un entorno altamente competitivo por empresas tanto nacionales como internacionales, siendo este uno de los propósitos fundamentales al que deberían apostar los empresarios colombianos para crear un impacto positivo en la sociedad y aportar a la competitividad nacional. Bakery Service Foods, es una empresa dedicada a la comercialización y distribución de insumos de panadería con sede en el barrio Carvajal en la ciudad de Bogotá. Desde su constitución, el 29 de diciembre de 2008, la empresa ha buscado posicionarse en un mercado en donde tanto empresas grandes como Grasco, Grupo Team, Sigra, Duquesa, Conaceites, Alvarado, Aceites Finos; así como microempresas sin infraestructura ni solidez económica, componen un entorno altamente competitivo y hacinado que representa un desafío para una pequeña empresa familiar que no cuenta con un músculo financiero significativo. Por otra parte, Bakery Service Foods a traviesa por un período de alta incertidumbre debido a que el proveedor que representa el 85% de las ventas de los productos a los cuales representan, FANAGRA S.A, atraviesa por una completa reestructuración debido a la venta de dicha empresa a una multinacional suiza. Esta situación representa un alto riesgo para la compañía y exige que se emprendan acciones oportunas que les permitan reducir la alta dependencia en un único proveedor. Teniendo en cuenta que una de las ambiciones desde la fundación de la compañía ha sido incursionar y ser una empresa competitiva en el mercado de Food Service, que perdure en el tiempo, ¿Qué tan viable es diversificar el portafolio de la empresa Bakery Service Foods (BSF) en el mercado Food Service? Con este proyecto se busca diseñar una propuesta de diversificación de portafolio para la empresa Bakery Service Foods (BSF) analizando el mercado Food Service, por medio del modelo de Ventaja Competitiva de Michael Porter; lo anterior, con el propósito de que la empresa se consolide en este mercado como un aliado estratégico para sus clientes y representados, y con un modelo de negocio sostenible a largo plazo. Finalmente, se espera que a través de la propuesta de mejora para Bakery Service Foods, se afiancen los conocimientos administrativos obtenidos durante el pregrado en Administración de Empresas, aplicando satisfactoriamente las herramientas, metodologías y bases conceptuales adquiridas, para enriquecer el proceso de aprendizaje profesional y aportar valor a una empresa colombiana desde el mercado de Food Service.
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Currently, the identification of two cryptic Iberian amphibians, Discoglossus galganoi Capula, Nascetti, Lanza, Bullini and Crespo, 1985 and Discoglossus jeanneae Busack, 1986, relies on molecular characterization. To provide a means to discern the distributions of these species, we used 385-base-pair sequences of the cytochrome b gene to identify 54 Spanish populations of Discoglossus. These data and a series of environmental variables were used to build up a logistic regression model capable of probabilistically designating a specimen of Discoglossus found in any Universal Transverse Mercator (UTM) grid cell of 10 km × 10 km to one of the two species. Western longitudes, wide river basins, and semipermeable (mainly siliceous) and sandstone substrates favored the presence of D. galganoi, while eastern longitudes, mountainous areas, severe floodings, and impermeable (mainly clay) or basic (limestone and gypsum) substrates favored D. jeanneae. Fifteen percent of the UTM cells were predicted to be shared by both species, whereas 51% were clearly in favor of D. galganoi and 34% were in favor of D. jeanneae, considering odds of 4:1. These results suggest that these two species have parapatric distributions and allow for preliminary identification of potential secondary contact areas. The method applied here can be generalized and used for other geographic problems posed by cryptic species.
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Este trabalho de investigação centra-se no contributo dos exames de superfície e nas análises micro-analíticas no estudo de vinte e uma pinturas atribuídas à oficina de Frei Carlos, um dos grandes Mestres Luso-Flamengos ativos em território Nacional durante a primeira metade do século XVI. A "Pintura Luso-Flamenga" é uma expressão comummente usada na história da pintura Portuguesa do primeiro terço do século XVI e no seu sentido mais básico designa o trabalho de mestres flamengos que se instalaram em Portugal durante o reinado de D. Manuel I (1495- 1521) contribuindo decisivamente para o processo de renovação da pintura Portuguesa na época. O estudo integrado combina a pesquisa histórica em fontes documentais com exames de superfície e de caracterização material das obras de arte. O estudo material das pinturas foi realizado através de microscopia ótica, microscopia de infravermelhos com transformada de Fourier, espectroscopia de micro-Raman, microscopia eletrónica de varrimento acoplada com espectrometria de energia dispersiva de raios X, micro- difração de raios-X, cromatografia líquida de alta eficiência e pirólise acoplada à cromatografia gasosa /espectrometria de massa. Esta investigação envolveu técnicas complementares de análise de superfície e de ponto no estudo técnico e material das preparações, imprimitura, desenho subjacente, camadas pictóricas e sucessões estratigráficas, dando a conhecer os materiais utilizados na execução técnica das pinturas e evidenciando especificidades técnicas da produção artística. Este estudo pretende inclusivamente evidenciar alguns detalhes técnicos do artista que possivelmente estão relacionados com a herança das práticas Flamengas. O conhecimento de algumas particularidades da técnica deste Mestre também permitiu estabelecer comparações com duas pinturas que haviam sido atribuídas, com algumas reservas, a esta oficina de pintura Luso-Flamenga. Mais recentemente, como resultado de um estudo colaborativo, foi realizada uma ampla campanha de reflectografia infravermelhos, introduzindo novos dados acerca da execução técnica do desenho subjacente, o que contribuiu para diferenciar, nestas duas pinturas, outra "mão", atribuída então a um seguidor de Frei Carlos. Esta investigação introduz um novo e profundo conhecimento sobre a Oficina de Frei Carlos, permitindo estabelecer comparações com a obra do seu seguidor e com uma pintura também atribuída a esta oficina e que incorpora o Museu da National Gallery (NG5594), evidenciando os materiais utilizados na técnica de produção artística e especificidades técnicas aliadas aos processos criativos/ construtivos que permitem estabelecer os pontos de contacto e de diferenciação entre estas obras; Varieties and styles in the works attributed to Frei Carlos - new perspectives Abstract: This investigation is focused on the contributions of surface exams and micro-analytical research in the study of twenty one paintings attributed to Frei Carlos workshop, one of the most important Portuguese-Flemish painters active in our country during the first half of sixteen Century. "Portuguese-Flemish Painting" is a common expression used in the history of Portuguese painting of the first third of the sixteenth century and in its most basic meaning designates the work of Flemish masters who settled in Portugal during the reign of King Manuel I (1495-1521) contributing decisively to the process of renewal of Portuguese painting at the time. The integrated approach combines historical research on documental sources with surface examination and material characterization of the paintings by using state-of-art analytical techniques. Microanalysis was carried out by optical microscopy, micro-Fourier-transform infrared-spectroscopy, micro-Raman spectroscopy, scanning electron microscopy coupled with energy dispersive X-ray spectrometry, micro-X-ray diffraction analysis, high performance liquid chromatography and Pyrolysis gas chromatography mass spectrometry. This complementary surface and analytical research was involved in the technical and material characterization of grounds, underdrawings, primings, paint layers and its multi-layered build-up, providing access to the painter´s materials used in the technical execution of the paintings and details of the technique of artistic production. This study also intends to expose some usual details of the artist’s technique which are possibly related to the Master´s Flemish influence. The knowledge of some particularities of the Master´s technique also allowed a new comparison with two paintings that had been attributed with some reserves to this Portuguese-Flemish workshop. More recently, as a result of a collaborative study, an extensive infrared reflectography campaign was made, giving new data concerning underdrawings technical execution and contributing to differentiate, in these two paintings, another “hand”, attributed to a follower of Frei Carlos. Complementary analytical research also added a new and deep insight into Frei Carlos workshop, his follower and a panel that still attributed to Frei Carlos workshop that integrates the National Gallery´s Museum (NG5594), evidencing the materials used in technical production, their models and sources of artistic inspiration, techniques and pictorial construction procedures that could specifically relate or distinguish between them.
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ResumenEl presente artículo se propone como una disertación en torno al fenómeno del abuso sexual infantily el Backlash, comprendiendo a este último como un contra-movimiento social que buscalegitimar diversas manifestaciones de violencia en contra de las mujeres y las personas menoresde edad. En aras de alcanzar dicho propósito, el artículo parte de la conceptualización del términoabuso sexual infantil, resaltando sus principales características y consecuencias, continúa con unadiscusión conceptual en torno al Backlash y sus principales derivaciones y concluye con una reflexiónrespecto a la relación entre este y el abuso sexual infantil. Producto del recorrido emprendido seafirma que, si bien el Backlash nace como una respuesta contraria y contestataria al éxito obtenidopor el movimiento de mujeres, ha evolucionado e incursionado en otras áreas temáticas, como lo esel abuso sexual infantil, cuya comprensión y atención se ha visto influenciada por teorías “pseudocientíficas” como el síndrome de alienación parental y el síndrome de falsas memorias, desde lascuales se desacredita la revelación de las víctimas. En tanto el uso de teorías compatibles con elBacklash en procesos de custodia y juicios por denuncias de abuso sexual se encuentra en aumentovertiginoso, se concluye que el movimiento de derechos humanos debe fortalecer una respuestaconjunta y sólida frente a esta reacción extrema.AbstractThe present article is a dissertation proposal regarding the child sexual abuse phenomenon and the Backlash, being the last a social countermovement which pretends to legitimize various manifestations of violence towards women and underage people. The article starts from the conceptualization of the term child sexual abuse, highlighting its key characteristics and consequences, moving on to a conceptual discussion concerning Backlash and its main derivations, and ending in a reflection about its relationship with child sexual abuse. From the research undertaken it is stated that, while Backlash started out as a counter response to the success achieved by the women movement, it has evolved and moved into other thematic areas, such as child sexual abuse, which understanding and focus have been influenced by pseudoscientific theories like the parental alienation syndrome and the false memory syndrome, from which the victims’ declarations are discredited. While the use of Backlash compatible theories in custody processes and sexual abuse accusation trials shows an accelerated increase, it is concluded that the human rights movement needs to build up a solid and joint answer against this extreme response.Keywords:Backlash, child sexual abuse, parental alienation syndrome, false memories syndrome.