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Triptolide, the predominant biologically active component of the Chinese herb Tripterygium wilfordii Hook f., possesses numerous pharmacological activities, including anti-inflammatory, anti-fertility, anti-neoplastic, and immunosuppressive effects. However, toxicity and severe adverse effects, particularly hepatotoxicity, limit the clinical application of triptolide. Licorice root extract contains various bioactive compounds and is potent hepatoprotective. Magnesium isoglycyrrhizinate, a magnesium salt of the 18α-glycyrrhizic acid stereoisomer of glycyrrhizic acid, is used clinically in China to treat chronic viral hepatitis and acute drug-induced liver injury. The aim of this study was to investigate the role of the factor erythroid 2-related factor 2 pathway in the protective effects of LE and MIG against triptolide-induced hepatotoxicity. Hepatotoxicity models were established in L-02 cells and rats using triptolide, and the protective effects of LE and MIG were investigated in vitro and in vivo, respectively. LE and MIG significantly protected against triptolide-induced cytotoxicity. Additionally, triptolide decreased the mRNA and protein levels of Nrf2 and down-regulated Nrf2 target genes, including UGT1A, BSEP, and MRP2, while pretreatment with LE and MIG reversed these effects. Finally, Nrf2-involved antioxidant responses were activated in the presence of LE and MIG.

O Lúpus Eritematoso Sistêmico (LES) é uma doença autoimune, multissistêmica, que acomete o tecido conjuntivo, com amplo espectro de manifestações clínicas e de etiologia pouco conhecida. A perda da tolerância imunológica leva a produção de autoanticorpos, depósitos teciduais de imunocomplexos, ativação do sistema complemento e processos inflamatórios crônicos. O diagnóstico atual estabelecido por meio de complexos critérios desenvolvidos pelo American College of Rheumatology aliado ao curso imprevisível do LES, com episódios de atividade e remissão, evidenciam a carência por biomarcadores específicos que auxiliem no diagnóstico e monitoramento desta patologia. Neste contexto, o presente estudo objetivou identificar, pela metodologia de CBA, os biomarcadores inflamatórios: ICAM-1, IL-8, IFN-, IP-10, MCP-1, MIG, MIP-1, RANTES e VEGF em amostras de soro de pacientes portadores de LES e em grupos controles (portadores de outras doenças autoimunes e indivíduos saudáveis) e que pudessem auxiliar no diagnóstico da doença. Participaram deste estudo 134 voluntários, distribuídos no grupo LES, com 46 pacientes (22 pacientes com baixa atividade SLEDAI 2k 4; 24 pacientes com atividade moderada/alta SLEDAI 2k > 4), 42 pacientes controles com outras doenças autoimunes (grupo ODA) e 8 voluntários saudáveis (grupo CONTROLE). Foram identificados resultados promissores em 5 dos 9 biomarcadores avaliados. As quimiocinas MIG (p = 0,000), RANTES (p = 0,000) e IP-10 apresentaram resultados estatisticamente diferentes entre os pacientes com LES e controles saudáveis, sendo esta última quando avaliado em pacientes com LES diferentes níveis de atividade (LESBA:CONTROLE; p = 0,009 / LESAMA:CONTROLE; p = 0,023), enquanto as concentrações de IL-8 (p = 0,000) e MIP-1 (p = 0,000) foram estatisticamente diferentes entre os pacientes com LES e com outras doenças autoimunes. As quimiocinas IL-8 (p = 0,026), IP-10 (p = 0,002), MIG (p =0,037), MIP-1 (p = 0,000) e RANTES (p = 0,037) correlacionaram-se com atividade do LES, apresentando níveis estatisticamente diferentes entre pacientes portadores de LES com baixa atividade e atividade moderada/alta. Correlações foram evidenciadas entre a idade dos pacientes com LES com os biomarcadores ICAM-1 (p = 0,009), IFN- (p = 0,002) e MIG (p = 0,0014) e em relação a idade do grupo ODA, correlacionou-se com a quimiocina IL-8 (p = 0,049). Não evidenciamos resultados significativos nas análises de ICAM-1, IFN-, MCP-1 e VEGF entre os grupos avaliados. Systemic Lupus Erythematosus (SLE) is an autoimmune, multisystemic disease that affects connective tissue, with a broad spectrum of clinical manifestations and poorly known etiology. The loss of immunological tolerance leads to autoantibody production, tissue deposits of immune complexes, complement system activation and chronic inflammatory processes. The current diagnosis, established through complex criteria developed by the American College of Rheumatology, allied to the unpredictable course of SLE, with activity and remission episodes, evidences the lack of specific biomarkers that aid in the diagnosis and monitoring of this pathology. In this context, the present study aimed to identify the inflammatory biomarkers ICAM-1, IL-8, IFN-, IP-10, MCP-1, MIG, MIP-1, RANTES and VEGF in serum of patients with SLE and in control groups (carriers of other autoimmune diseases and healthy individuals) and that could also help in the diagnosis of the disease. A total of 134 volunteers, distributed in the SLE group with 46 patients (22 patients with low activity - SLEDAI 2k 4, 24 patients with moderate / high activity - SLEDAI 2k > 4. Forty-two patients with other autoimmune diseases) and 44 healthy volunteers (CONTROL group) took part in this study. Promising results were identified in five out of nine of the evaluated biomarkers. The chemokines MIG and RANTES showed statistically different results among SLE patients and healthy controls (p = 0.0 for both groups). IP-10 levels were significantly different in relation to the control group when evaluated in SLE patients at different levels of activity. The concentrations of Il-8 and MIP were statistically different between SLE patients and those with other autoimmune diseases (p = 0.0 for both cytokines in these groups). The chemokines IL-8 (p = 0.026), IP-10 (p = 0.002), MIG (p = 0.037), MIP-1 (p = 0.0) and RANTES (p = 0.037) correlated with SLE activity showing statistically different levels among SLE patients with low or moderate/high activity. Correlations were evidenced in ages of SLE patients to ICAM-1, IFN- and MIG biomarkers. On the other hand, concerning the ODA group, the age of individual in this group correlated only with chemokine IL-8. We did not observe significant results in ICAM-1, IFN-, MCP-1 and VEGF analysis among evaluated groups.

WOS: 000443401800001, In this paper, the effects of post-weld heat treatment on modification of microstructures and mechanical properties of friction stir welded and gas metal arc welded AA6061-O plates were compared with each other. Gas metal arc welding and friction stir welding were used as the applicable welding processes for AA6061-O alloys. The applied post-weld heat treatment consisted of solution heat treatment, followed by water quenching and finally artificial aging. The samples were classified as post-weld heat treated and as-welded joints. The microstructural evolution, tensile properties, hardness features and fracture surfaces of both as-welded and post-weld heat treated samples were reported. The results clearly showed that friction stir welding process demonstrated better and more consistent mechanical properties by comparison with the gas metal arc welding process. The weld region of as-welded samples exhibited a higher hardness value of 80 HV0.1 compared to the base material. In addition, the feasibility of post-weld heat treatment in order to enhance the mechanical properties and to obtain more homogeneous microstructure of 6061-O aluminum alloys was evaluated.

[ES] En los últimos años ha habido una gran evolución en la forma en que se comportan los mercados globales así como en las demandas de los clientes. Estos hechos están obligando a las empresas a cambiar su forma de producir. Con la aparición de la globalización y el aumento de la interacción entre las empresas, los clientes individuales demandan productos más específicos en breves períodos de tiempo, por lo que las empresas se enfrentan a tres desafíos importantes: Primero la globalización mencionada: en el mundo actual, los usuarios pueden acceder a todo tipo de mercados. Todos nosotros como clientes demandamos las mejores condiciones con los precios más bajos. Ciclos de vida del producto más cortos: los mercados específicos, especialmente los tecnológicos, están en constante desarrollo. Este factor obliga a las empresas a actualizarse en cortos períodos de tiempo. Requisitos dinámicos: la demanda de los clientes nunca deja de cambiar, además, no todos los usuarios tienen las mismas demandas. Estos desafíos llevan a las empresas a intentar tratar a los clientes como seres individual, lo que produce no solo un aumento de la variedad de productos externos, sino también un aumento más importante de la variedad de productos internos. Como resultado, las empresas sufren un aumento en la complejidad y, por lo tanto, un aumento en los costos. Esta tesis se centra en hacer frente a estos problemas en una familia de productos de máquinas láser, específicamente en la parte guía de la máquina, propiedad de la empresa ERLAS Erlanger Lasertechnik GmbH. Esto se logra mediante la aplicación de un método desarrollado por el Instituto de Desarrollo de Productos y Diseño de Ingeniería Mecánica de la Universidad de Tecnología de Hamburgo. El método tiene como objetivo reducir la variedad interna entre los productos de la misma familia, pero siempre guardando la variedad externa, para que las solicitudes de los clientes sigan siendo satisfechas. Con el método Diseño para la variedad (Kipp 2012), el diseñador tiene la posibilidad de desarrollar la arquitectura del producto para minimizar los costos de todas las etapas de la vida de los productos variables. Estos costos se pueden dividir en: Costes, que incluyen los costes de producción y los costes de complejidad 1. Los costes de producción se refieren a los costes de los materiales y de fabricación 2. Costes de complejidad. Representan el porcentaje más alto e incluyen, entre otros, desarrollo, administración, logística y costes de stock Costes de uso, que se divide en costes de inversión (precio de compra) y costes de operación (costo de energía) Este método trata de trabajar con módulos del producto, que serán proporcionados por el Instituto. Estos módulos se formarán de forma que la modificación de un módulo afecte a la menor parte posible de la máquina. Al trabajar con los componentes, es muy importante hacer una diferenciación entre componentes variables y estandar para reducir los primeros. Con el método de Diseño para la variedad esperamos cumplir dos objetivos principales: Reducción de la variedad interna para reducir costos a lo largo de todo el ciclo de vida del producto Detectar variantes innecesarias del producto para borrarlas y de esta manera ajustar la gama de productos para reducir los costos de la complejidad Los pasos que se seguirán a lo largo de los meses de trabajo son los siguientes: 1. Primeras investigaciones. Introducción en el campo de estudio 2. Definición del problema y establecimiento del objetivo del proyecto 3. Definición del método de Diseño de variedad para comprender cómo funciona y conocer los pasos que se deben seguir para aplicar el método 4. Introducción a la máquina y definición de los módulos para comenzar a aplicar el método 5. Aplicación del método con los siguientes pasos: 5.1 Árbol de variedad externa 5.2 Gráfico de interfaz de, [EN] In the last decades there has been a huge update in the way that global markets behave, also in the requests of clients. These facts are forcing companies to change their way of producing. With the appearance of globalisation and the increase of interaction between companies, individual customers demand more specific products in brief periods of time, for this reason companies are facing three important challenges: The first mentioned globalization: in the current market users can access every market. All of us as clients demand the best conditions with the lowest prices. Shorter product life cycles: Specific markets, especially the technological ones, are in a constant development. This factor forces companies to update within short periods of time. Dynamic requirements: the demand of the clients never stop changing, besides not every user has the same demands. These challenges lead companies trying to treat customers as an individual one, which produces not only an increase of the external product variety but also a more important increase of the internal product variety. As a result, companies suffer an increase of complexity and, hence, a rise of the costs. This thesis focuses on facing these problems in a product family of laser machines, specifically in the guiding part of the machine, property of the company ERLAS Erlanger Lasertechnik GmbH. This is achieved by the application of a method developed by the Institute for Product Development and Mechanical Engineering Design of Hamburg University of Technology. The method aims to reduce internal variety among products of the same family but always saving the external variety, so that the requests of the clients continue to be satisfied. With the Design for Variety method (Kipp 2012), the designer has the possibility of developing the product architecture to minimise the costs of all the life stages of the variant products. It can be divided in: Costs, which include the production costs and the complexity costs 1. Production cost refers to the material costs and the manufacturing costs 2. Complexity cost. Are the main percentage and includes among others development, administration, logistic and stock cost Use cost, which are divided in investment cost (purchase price) and cost of operation (energy cost) This method is about working with components of the product, which will be provided by the Institute. These modules will be formed in a way, so that the modification of one module affects the least parts of the machine as possible. When working with the components it is very important to make a differentiation between variant and standardised components in order to reduce the first ones. With the method of Design for Variety we look forward to fulfilling two main goals: Reducing internal variety to reduce costs across the whole product life cycle Detecting unnecessary product variants to erase them and in this way adjusting the range of products to reduce costs of complexity The steps that will be followed throughout the months of work are the following: 1. First researches. Introduction in the field of study 2. Definition of the problem and setting the aim of the project 3. Definition of the method of Design of variety to understand how it works and to know better the steps that must be followed to apply the method 4. Introduction to the machine and definition of the modules to start applying the method 5. Application of the method with the following steps: 5.1 Tree of external variety 5.2 Module interface graph 5.3 Product family functional structure 5.4 Variety allocation model 6. Analysis of the results obtained with the tools and search of the solutions regarding relevant criteria (costs, number of variant components, etc.) 7. Evaluation and choice of the gained product concepts using the criteria 8. Final steps. Conclusion and summary

The effect of cinnamon (Cinnamomum zeylanicum) bark essential oil (CBEO) on human skin cells has not been elucidated. Therefore, we investigated the activity of a commercially available CBEO in a validated human dermal fibroblast system, a model of chronic inflammation and fibrosis. We first evaluated the impact of CBEO on 17 protein biomarkers that play critical roles in inflammation and tissue remodeling. The impact of CBEO on genome‐wide gene expression was also evaluated. CBEO showed strong anti‐proliferative effects on skin cells and significantly inhibited the production of several inflammatory biomarkers, including vascular cell adhesion molecule‐1, intercellular cell adhesion molecule‐1, monocyte chemoattractant protein‐1, interferon gamma‐induced protein 10, interferon‐inducible T‐cell alpha chemoattractant, and monokine induced by gamma interferon. In addition, CBEO significantly inhibited the production of several tissue remodeling molecules, including epidermal growth factor receptor, matrix metalloproteinase‐1, and plasminogen activator inhibitor‐1. Macrophage colony‐stimulating factor, which is an immunomodulatory protein molecule, was also significantly inhibited by CBEO. Furthermore, CBEO significantly modulated global gene expression and altered signaling pathways, many of which are important in inflammation, tissue remodeling, and cancer biology. The study shows that CBEO is a promising antiinflammatory agent; however, further research is required to clarify its clinical efficacy. © 2017 The Authors. Phytotherapy Research published by John Wiley & Sons Ltd.

This study aims to demonstrate the effects of pulsed current on the welding pool and fusion zone microstructures of the aluminum 2014 alloy matrix composite material reinforced with 14 and 20 vol% SiC particles. A programmable synergic controlled MIG welding machine with pulsed power supply was used. One hundred Ampere and 120 Ampere pulsed current values were used to determine the effect of heat input on microstructures. A 1 mm diameter SG-AlSi5 wire was used as filler material. The microstructures were studied using a scanning electron microscope (SEM) with energy dispersive X-ray (EDX) spectroscopy, and the phase analyses were performed via X-ray diffraction analyzer (XRD). The study showed that increasing the SiC rate has a greater effect on the formation of Al4C3 phase than increasing the heat input values. Al4C3 formation was not formed as a needle-like structure. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This study aims to demonstrate the effects of pulsed current on the welding pool and fusion zone microstructures of the aluminum 2014 alloy matrix composite material reinforced with 14 and 20 vol% SiC particles. A programmable synergic controlled MIG welding machine with pulsed power supply was used. One hundred Ampere and 120 Ampere pulsed current values were used to determine the effect of heat input on microstructures. A 1 mm diameter SG-AlSi5 wire was used as filler material. The microstructures were studied using a scanning electron microscope (SEM) with energy dispersive X-ray (EDX) spectroscopy, and the phase analyses were performed via X-ray diffraction analyzer (XRD). The study showed that increasing the SiC rate has a greater effect on the formation of Al4C3 phase than increasing the heat input values. Al4C3 formation was not formed as a needle-like structure.

Although Titanosauria is the most diverse and late-surviving sauropod lineage, cranial elements are known for just over 24 of its 70+ genera - the vast majority of which are fairly fragmentary and restricted to the Late Cretaceous. Only three complete titanosaur skulls have been described to date; two of these are from the latest Cretaceous (Nemegtosaurus, Rapetosaurus), and the third, Tapuiasaurus, is from the Early Cretaceous (Aptian). In this contribution, we build on the initial treatment of the taxon by providing a complete description of the cranial elements that benefits from additional preparation and computed tomography imaging. We identify six additional features diagnosing Tapuiasaurus macedoi, including a jugal with an elongate lacrimal process forming much of the posteroventral border of the antorbital fenestra, a lateral temporal fenestra divided by a second squamosal–postorbital contact, and upper jaw teeth with labial wear facets. We directed the new morphological data in Tapuiasaurus as well as other observations towards a re-analysis of its phylogenetic position within Titanosauria. Our analysis yielded 34 most parsimonious trees, most of which recovered Tapuiasaurus in a basal position adjacent to the Early Cretaceous taxa Malawisaurus and Tangvayosaurus, but two trees recovered it within Late Cretaceous nemegtosaurids. We explored the effects of missing data and missing stratigraphic ranges on our results, concluding that (1) when missing data levels are high, resolution of even small amounts of that missing data can have dramatic effects on topology, (2) taxa that are mostly scored for characters that cannot be scored in other taxa may be topologically unstable and (3) there were several suboptimal trees that had greatly improved stratigraphic fit with relatively little compromise in terms of tree length. Fil: Wilson, Jeffrey A.. University of Michigan; Estados Unidos Fil: Pol, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; Argentina Fil: Carvalho, Alberto B.. Universidade de Sao Paulo; Brasil Fil: Zaher, Hussam. Universidade de Sao Paulo; Brasil

Lymphoma-associated hemophagocytic syndrome (LAHS) is a serious disorder, and its early diagnosis and treatment with appropriate chemotherapy are very important. However, reliable markers for early diagnosis of LAHS have not been identified. We screened serum cytokines using a newly introduced assay system, cytometric bead array (CBA), and identified interferon-inducible protein 10 (IP-10)/CXCL10 and monokine induced by interferon gamma (MIG)/CXCL9 as useful markers. Serum concentrations of IP-10 and MIG at the time of LAHS diagnosis were greater than 500 and 5,000 pg/ml, respectively. The sensitivity and specificity for LAHS diagnosis were 100 and 95 %, respectively, when we set the above values as the cut-off levels. Serum levels of these two chemokines were already elevated at the time of admission and significantly decreased after successful treatment, indicating their usefulness for both the diagnosis and therapeutic outcomes for LAHS. IP-10 and MIG were also useful in distinguishing severe from moderate/mild LAHS, and B-cell-type LAHS from T-cell/natural killer cell-type LAHS. Furthermore, IP-10 and MIG were of use to distinguish LAHS from sepsis in patients with hematologic malignancies. Rapid measurement of IP-10 and MIG by CBA appeared to be important for early diagnosis and treatment of LAHS.

MIG/MAG je elektrolučno zavarivanje taljivom elektrodom u zaštiti aktivnog ili inertnog plina. Ovaj postupak može se primijeniti na široki spektar materijala različitih debljina i vrsta. Postupak ima više načina prijenosa samoga metala. Prijenos metala kratkim spojem primjenjuje se kod zavara tanjih limova, pogodan je još i za zavarivanje korijena zavara kod debljih komada. Prijenos metala štrcajućim lukom primjenjiv je na gotovo sve materijale. Kod prijenosa metala mješovitim lukom javljaju se prijenos metala štrcajućim lukom i kratkim spojem u određenim intervalima. Prijenos metala pulsirajućim lukom primjenjiv je u svim položajima, ali i na širi raspon debljine određenog materijala. Za svaki od ovih prijenosa metala potrebni su određeni parametri. Zaštitni plinovi koji se javljaju ovome postupku zavarivanja bitni su jer štite mjesto zavarivanja, ali i kapljice rastaljenog metala za vrijeme prolaska kroz električni luk. Primjenom pojedinog plina, ali i načina prijenosa metala i vrsti i debljini materijala, ali i ostalih parametara, tako se primjenjuju i dodatni materijala koji su u rasponima debljine od 0.6 do 2.4 mm. Dodatni materijal može biti puni ili praškom punjeni. Ostali parametri kao i ta dva utječu na sami zavar. Stoga je bitno u samoj primjeni odredi točne parametre, kako bi se izbjegle neželjene greške u samome zavarivanju, ali i samom zavaru koji mogu biti: poroznost, naljepljivanje, štrcanje, pukotine i penetracija. U primjeni su i suvremeni postupci MIG/MAG zavarivanja koji se primjenjuju za pojedina zavarivanja gdje su najučinkovitiji i gdje ne pojavljuju greške kao kod klasičnih MIG/MAG postupaka. Tandem zavarivanje, zavarivanje s dvjema žicama koje je brže od ostalih konvencijalnih MIG/MAG postupaka. Primjenom robota u postupcima zavarivanja postiže se sve veća učinkovitost MIG/MAG postupaka zavarivanja. MIG/MAG is an arc welding with consumable electrode and protected with active or inert gas. This procedure can be applied on the wide specter of various thickness and types. Procedure has several ways of metal melting. Metal melting using short circuit is applied at welding thin sheet metal and is also usable in welding initial joints in thicker pieces. Metal melting using sproutin arc is appliable on almost all materials. When using combined arc, sprouting arc and short circuit both appear in short intervals. Metal melting with pulsating arc is appliable in all positions, but also on a wider scale of thickness of a particular material. For each of these meltings certain parameters are required. Shielding gases that appear during this procedure are important because they shield the welding place, but also the drops of melted metal during their 2 passing throught the electric arc. By using a certain gas, but also a method of melting and depending on the kind and thickness of the material and other parameters as well, that is how additional materials are applied with thickness varying for 0.6 to 2.4 mm. Additional material can be composite or powder-filled. Other parameters as well as these two affect the weld itself. Therefore it is important in application itself to determine exact parameters, so to avoid unwanted errors in the welding itself, but also on the welding place, which can be: porosity, sticking, splashing, cracks and penetration. In appliance are modern procedures of MIG/MAG welding which are used for certain weldings in which they are most effective and in which no errors appear as with classic MIG/MAG procedures. Tandem welding, welding with two wires is faster than other conventional MIG/MAG procedures. By using robots in the welding processes greater efficiency of MIG/MAG welding procedure is achieved.

Background Interleukin-6 (IL-6), an inflammatory cytokine, plays important roles in cerebrospinal fluid (CSF) after subarachnoid hemorrhage (SAH). Chemokines are chemoattractant cytokines that regulate trafficking of monocytes/macrophages and lymphocytes to sites of inflammation. However, no studies have been reported regarding the temporal expression of these cytokines in CSF after SAH. Findings The concentrations of IL-6, monocyte chemoattractant protein-1 (MCP-1), interferon-γ-inducible protein-10 (IP-10), and monokine induced by interferon-γ (MIG) in the CSF of ten patients with SAH were measured using ELISA kits over a period of 14 days. All aneurysms were located in the anterior circulation. CSF samples from patients with unruptured aneurysms were used as controls. The concentration of IL-6 significantly increased during the acute stage of the disease. The concentration of MCP-1 increased from days 1 to 5, peaking on day 3, and decreased thereafter. The concentrations of IP-10 and MIG progressively increased, peaked on day 5, and then gradually decreased. There were strong correlations between the maximum levels of IL-6 and MCP-1 and IP-10 and MIG on day 5. The maximum level of IL-6 was much higher in poor outcome patients than in good outcome patients. Conclusions The present investigation demonstrated that increases in IL-6 levels may induce the expression of MCP-1 in CSF after SAH, followed by increases in the expression of IP-10 and MIG. Dynamic changes in the levels of these cytokines may induce inflammation and may be closely associated with the development of delayed ischemic neurological deficits after SAH. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0675-7) contains supplementary material, which is available to authorized users.

Svetsning är idag den mest använda sammanfogningsmetoden för metaller, och pågrund av metodens relativt enkla utförande och höga produktivitet är MIG/MAG-svetsning idag den mest använda svetsmetoden industriellt i hela världen. En viktig del av svetsutrustningen till MIG/MAG är svetspistolen. Strömöverföringen från pistol till tillsatsmaterial sker genom en komponent som kallas kontaktrör. Kontaktröret är traditionellt tillverkat av koppar. Målet med detta examensarbete är att fastställa huruvida det nya materialet i ett kontaktrör påverkar grundmaterialet och svetsgodset negativt vid svetsning. Slutsatsen som drogs var att det nya materialet i kontaktröret inte har en negativ påverkan på grundmaterialet eller svetsgodset vid svetsning. Produkten kaneventuellt leda till stora ekonomiska och ekologiska vinster för svetsindustrin i framtiden.

In this master thesis different overlay welding methods suitable for boiler application has been investigated. The purpose of this project is to define advantages and disadvantages for each overlay welding methods and suggest some evaluation criteria on some commercial and experimental alloys aimed for overlay welding material. Many components in a boiler are made of low alloy steel and the atmosphere in the furnace region can be very complex; therefore many different types of corrosion can occur. Weld overlay is a process where one or multiple layers of corrosion resistant material are applied to a base material. The two overlay welding methods investigated in this study were Tungsten Inert Gas welding and Metal Inert/Active Gas welding. Tests were performed with FeCrAl alloys (Kanthal A, Kanthal D and some experimental alloys). FeCrAl alloys in general are ferritic iron-based steels with a typical concentration of 20-23 wt. % chromium and ~5 wt.% aluminum. Different overlay welding evaluation was made; visual examination, dye penetrant inspection, macro/micro examination, side bend test and short term corrosion test (~50hours). Conclusion of this thesis is that MIG welding is a more productive method than TIG, but more defects such cracks and lack of fusion can be produced for MIG welding. These defects can be “fixed” if welding parameters is optimized. If repairing a certain place TIG welding is a better option. A conclusion about number of layers; one layer with MIG welding is almost as thick as three layers with TIG welding with welding wire Ø 1mm. Three welding evaluation that is really important is visual examination, dye penetrant testing and corrosion test in order to choose which overlay welding method is suitable in boiler application. I detta examensarbete har olika påsvetsningsmetoder som är lämpliga för en pannapplikation undersökts. Syftet med denna studie var att undersöka både för- och nackdelar med påsvetsningsmetoderna och föreslå några utvärderingskriterier på vissa kommersiella och experimentella legeringar som lämpar sig för påsvetsningsmaterial. Många komponenter i en panna är tillverkade av låg legerat stål och miljön där förbränningen sker kan vara väldigt komplex, därför kan det ske korrosion. Påsvetsning är en process där ett eller flera skikt av ett mer korrosionsbeständigt material appliceras på ett basmaterial. De två olika svetsmetoderna som undersöktes i denna studie var TIG-svetsning och MIG-svetsning. Testerna utfördes med FeCrAl legeringar (Kanthal A, Kanthal D och vissa experimentella legeringar). FeCrAl legeringar är i allmänhet ferritiska järnbaserade stål med 20-23% krom och ~5% aluminium. De utvärderingsmetoderna som undersöktes var: visuell undersökning, penetrantprovning, makro/ mikroundersökning, sidobockprovning och korttidskorrosionstest (~50 timmar). Slutsatsen av detta examensarbete är att MIG-svetsning är en mer produktiv metod än TIG, men fler defekter såsom bindfel och sprickor uppkom för MIG-svetsning. Dessa defekter kan ”fixas” genom optimering av svetsparametrar. Om man bara ska reparera ett specifikt område är TIG-svetsning ett bättre alternativ. En slutsats om antal lager är att ett lager med MIG-svetsning är nästan lika tjockt som tre lager med TIG-svetsning med Ø 1mm svetstråd. Tre svetsutvärderingar som är viktiga är visuell undersökning, penetrantprovning och korrosionstest för att välja vilken påsvetsmetod som är lämpligast i pannapplikation.

O processo MIG/MAG CA tem um potencial muito grande de aplicação, por permitir unir as características da soldagem MIG/MAG convencional (corrente contínua, com o eletrodo no positivo) com as de se usar corrente negativa na soldagem MIG/MAG. Entretanto, o formato de onda de corrente (alternada, pulsada no positivo e constante no negativo) demanda uma seleção criteriosa de seus inúmeros parâmetros de regulagem, o que vem limitando o estudo e aplicação desta versão de processo MIG/MAG. O objetivo deste trabalho foi propor e avaliar uma metodologia capaz de estimar os parâmetros de regulagem do processo MIG/MAG CA, de tal forma a se obter soldas com estabilidade de comprimento de arco e cordões com geometria adequada. É feita uma descrição passo a passo da definição dos parâmetros de entrada e da forma de se obter experimentalmente alguns valores de parâmetros necessários para estimação de outros valores de regulagem. As equações de estimação são apresentadas e discutidas. É feita uma demonstração da aplicação da metodologia, com a validação dos resultados pela comparação entre valores estimados e reais.The AC MIG/MAG process presents remarkable application potential, since it allows join the characteristics of the conventional MIG/MAG process (direct current, electrode positive) with the ones obtained when negative current is applied in MIG/MAG welding. However, the current wave shape (alternate, pulsed in positive and constant in negative polarities) demands a criterions selection of its innumerous setting parameters, fact that limits the development and application of this process version. The objective of this work was to propose and assess a methodology able to estimate the setting parameters of the CA MIG/MAG welding process, in such a way to result in welds with arc length stability and adequate bead geometry. A step-a-step description of the input parameter definitions and of the way to experimentally obtain some parameter values needed to estimate other setting parameters. The estimation equations are presented and discussed. A demonstration of the methodology application is carried out, with validation through actual welds.

Dada a importância do uso da polaridade variável na soldagem MIG/MAG (MIG/MAG-PV), com grande potencial para a aplicação de revestimento e para a soldagem de passe de raiz, �� fundamental investigar os efeitos de parâmetros do processo na formação do cordão e na taxa de fusão do arame-eletrodo. Esta última em especial, dada a maior taxa de fusão obtida pelo período de polaridade negativa. Desta forma, procurou-se avaliar o efeito de dois formatos de onda investigados anteriormente que possuem pausa de corrente antes e após o pulso principal do período de polaridade positiva, haja vista que estas condições se mostraram as mais estáveis. Investigou-se também o efeito do tipo de gás de proteção utilizado sobre as características geométricas do cordão de solda (representadas pela largura, penetração e reforço) e taxas de fusão e deposição e o rendimento. As soldagens foram executadas em simples deposição sobre chapas de aço SAE 1020 pelo processo MIG/MAG-PV com 30 e 50% de porcentagem de tempo com eletrodo em polaridade negativa. Os gases de proteção utilizados foram Ar+2%O2, Ar+5%O2, Ar+8%CO2 e Ar+15%CO2. Procurou-se manter o mesmo comprimento de arco em todos os testes, por meio da variação da velocidade de alimentação de arame. Além disto, foi mantida constante a relação velocidade de alimentação de arame pela velocidade de soldagem, com o objetivo de tentar manter o volume de metal depositado constante para comparação. Pode-se concluir que o melhor entendimento do comportamento da geometria em relação aos parâmetros e consumíveis utilizados auxiliará para garantir o perfil do cordão desejado de acordo com a aplicação. Aliado a isto, a análise da taxa de fusão do processo possibilita selecionar com mais coerência os parâmetros e consumíveis utilizados que forneçam menores perdas de material e maior produtividade.Due to the importance of variable polarity in MIG/MAG welding (MIG/MAG-PV) with great potential for overlaying and root pass applications, it is fundamental to assess the effect of process parameters on the bead formation and wire-burn rate, specially the latter, since higher melting rate is achieved by this process during negative polarity. Therefore, this work aims to assess the effect of two different waveforms previously investigated, in which current pauses before and after the main pulse during positive polarity (this condition leads to better stability). The shielding gas effect was also investigated for the bead geometry (width, penetration and reinforcement), melting rate, deposition rate and deposition efficiency. Bead-on-plate weldments were carried out over SAE 1020 carbon steel with MIG/MAG-PV welding at 30 and 50% of time in negative polarity. The employed shielding gases were Ar+2%O2, Ar+5%O2, Ar+8%CO2 and Ar+15%CO2. The arc length was kept approximately the same during the runs by varying the wire-feed speed. Also, the relationship between wire-feed speed and travel speed was kept constant in order to keep the same amount of deposited material. It is possible to conclude that the better understanding on the relationship among bead geometry, parameters and consumables leads to assure a desired bead profile, in accordance with a given application. Moreover, the melting rate analysis allows selecting more coherent parameters and consumables to assure lower material losses and high productivity.

Dada a importância do uso da polaridade variável na soldagem MIG/MAG (MIG/MAG-PV), com grande potencial para a aplicação de revestimento e para a soldagem de passe de raiz, é fundamental investigar os efeitos de parâmetros do processo na formação do cordão e na taxa de fusão do arame-eletrodo. Esta última em especial, dada a maior taxa de fusão obtida pelo período de polaridade negativa. Desta forma, procurou-se avaliar o efeito de dois formatos de onda investigados anteriormente que possuem pausa de corrente antes e após o pulso principal do período de polaridade positiva, haja vista que estas condições se mostraram as mais estáveis. Investigou-se também o efeito do tipo de gás de proteção utilizado sobre as características geométricas do cordão de solda (representadas pela largura, penetração e reforço) e taxas de fusão e deposição e o rendimento. As soldagens foram executadas em simples deposição sobre chapas de aço SAE 1020 pelo processo MIG/MAG-PV com 30 e 50% de porcentagem de tempo com eletrodo em polaridade negativa. Os gases de proteção utilizados foram Ar+2%O2, Ar+5%O2, Ar+8%CO2 e Ar+15%CO2. Procurou-se manter o mesmo comprimento de arco em todos os testes, por meio da variação da velocidade de alimentação de arame. Além disto, foi mantida constante a relação velocidade de alimentação de arame pela velocidade de soldagem, com o objetivo de tentar manter o volume de metal depositado constante para comparação. Pode-se concluir que o melhor entendimento do comportamento da geometria em relação aos parâmetros e consumíveis utilizados auxiliará para garantir o perfil do cordão desejado de acordo com a aplicação. Aliado a isto, a análise da taxa de fusão do processo possibilita selecionar com mais coerência os parâmetros e consumíveis utilizados que forneçam menores perdas de material e maior produtividade. Due to the importance of variable polarity in MIG/MAG welding (MIG/MAG-PV) with great potential for overlaying and root pass applications, it is fundamental to assess the effect of process parameters on the bead formation and wire-burn rate, specially the latter, since higher melting rate is achieved by this process during negative polarity. Therefore, this work aims to assess the effect of two different waveforms previously investigated, in which current pauses before and after the main pulse during positive polarity (this condition leads to better stability). The shielding gas effect was also investigated for the bead geometry (width, penetration and reinforcement), melting rate, deposition rate and deposition efficiency. Bead-on-plate weldments were carried out over SAE 1020 carbon steel with MIG/MAG-PV welding at 30 and 50% of time in negative polarity. The employed shielding gases were Ar+2%O2, Ar+5%O2, Ar+8%CO2 and Ar+15%CO2. The arc length was kept approximately the same during the runs by varying the wire-feed speed. Also, the relationship between wire-feed speed and travel speed was kept constant in order to keep the same amount of deposited material. It is possible to conclude that the better understanding on the relationship among bead geometry, parameters and consumables leads to assure a desired bead profile, in accordance with a given application. Moreover, the melting rate analysis allows selecting more coherent parameters and consumables to assure lower material losses and high productivity.

Não obstante a vasta quantidade de informações disponibilizadas nem sempre é fácil obter o conhecimento que se almeja alcançar, devido à dificuldade de catalogar a informação. Os sistemas de “descoberta de conhecimento” atuais centram-se na procura de palavras idênticas, podendo aqui observar-se variadas limitações, entre elas a falta de capacidade de interpretação. A compreensão do significado semântico do conjunto de expressões é uma característica do ser humano, sendo difícil de replicar em sistemas computacionais. O objetivo principal deste trabalho consiste na criação de um sistema de cálculo de semelhança semântica entre classes abstratas, sistema esse que deve possuir por base uma ontologia de conhecimento. Para atingirmos o objetivo proposto começou-se por identificar e analisar a necessidade de uma máquina conseguir simular ou melhorar a apreciação do ser humano relativamente à interpretação semântica. Apôs a definição e enquadramento do problema na área de conhecimento respetiva partiu-se para a criação do sistema capacitado de calcular uma medida de semelhança entre entidades, tendo em consideração a importância que o desempenho apresenta neste tipo de sistema.

Com o vasto volume de informação a circular diariamente na internet é crucial que a informação existente se mantenha atualizada, sob pena do utilizador perder o interesse em consultar a mesma. Como tal, torna-se importante que o website que pretendemos disponibilizar esteja de acordo com o modelo de negócio da organização e que nele contida se mantenha atualizada sem a constante intervenção do gestor de dados do website. Assim, o trabalho de investigação aqui realizado tem por principal objetivo o desenvolvimento de uma metodologia que possibilite a modelação conceptual da estrutura e dinâmica de um website neste contexto. Este sistema assenta na modelação dos vários elementos que compõem o website, descrevendo-os sintática e semanticamente. A modelação deve ainda representar a dinâmica de cada página, proporcionando flexibilidade na definição e alteração do modelo do sistema de informação, facilitando também o desenvolvimento e manutenção do software. Pretende-se pois que o sistema de software implemente estes modelos, eliminando intervenções humanas decorrentes de ações temporais decorrentes de processos associados ao contexto em estudo. Estas alterações devem refletir-se de imediato no website colmatando assim as lacunas existentes nos sistemas de gestão de conteúdos atualmente disponíveis ao utilizador.

In this experiment, the T-joint of a 6082 aluminum alloy was welded by metal inert gas (MIG) welding and a fatigue test was carried out at room temperature. The mechanisms of generating pores and of fatigue fracture in welded joints are revealed in the case of incomplete penetration. There are two main types of pores: pores that are not welded and pores that are near the upper weld line of the weld. During welding, bubbles in the molten pool are adsorbed on the surface oxide film that is not penetrated, and cannot be floated to form pores, since it is a T-shaped welded joint, the molten pool is overhanged during welding, thereby forming pores near the fusion line. The fatigue strength of the welded joint based on the S&ndash, N curve at 107 cycles is estimated to be 37.6 MPa, which can reliably be predicted in engineering applications. Fatigue tests show that fatigue cracks are all generated in the pores of the incomplete penetration, and it and the pores form a long precrack, which leads to large stress concentration, and the fracture occurs under a small applied load. Grain morphology around the pores also has a large effect on the fatigue properties of the T-weld joint. In the weld&rsquo, s fatigue fracture, it was found that the crack stable-extension zone exhibited ductile-fracture characteristics, and the instantaneous fault zone is composed of a large number of tear-type dimples showing ductile fractures.

Uma das principais vantagens do processo MIG/MAG é a alta produtividade. Na maioria das aplicações utiliza-se a polaridade positiva, devido a maior estabilidade do arco, geração de menos respingos e formação de cordões com geometria adequada. No entanto, em algumas aplicações, se demanda uma maior capacidade de produção do que a que o MIG/MAG convencional oferece. Na literatura é citado que a polaridade negativa proporciona maior taxa de fusão do que a positiva, apesar de levar à grande produção de respingos e formação inadequada do cordão. Lamentavelmente, não há muita informação disponível sobre os efeitos das variáveis do processo nessa polaridade, tão pouco justificativas sobre tal. Assim, neste trabalho se procurou entender a razão para que uma maior taxa de deposição aconteça na polaridade negativa, assim como o respectivo efeito sobre a geometria dos cordões. Para isto, foram realizadas soldagens MIG/MAG comparativas na polaridade positiva e negativa, usando duas composições de gases de proteção em dois valores de corrente. O modo de transferência e o comportamento do arco foram analisados por perfilografia sincronizada. O perfil geométrico do cordão foi avaliado por meio de procedimentos metalográficos. A partir dos resultados, que discordam em parte da literatura corrente, foi observado que tanto o modo de transferência como a morfologia e aspecto do cordão são dependentes da composição do gás de proteção. Para explicar os fenômenos inerentes à maior taxa de fusão do arame em CC-, sugere-se que o fato de o arco escalar as laterais do arame nesta polaridade seja o fator governante.One of the main advantages of the MIG/MAG process is its high productivity. Usually, the positive polarity is employed, due to a higher arc stability, less spattering and adequate bead profiles. However, a higher production capacity than observed in the conventional MIG/MAG process has been demanded for some applications. In the current literature related to MIG/MAG, it is mentioned that the negative polarity provides a higher fusion rate than the positive one, despite of leading to higher spattering and bead misshapen. Unfortunately, there is no much information available about the effects of process variables in this polarity, as much as concerning justifications. Thus, in this work was attempted to understand the reasons for a higher fusion rate at CC-, as well as the respective effect on the bead geometry. For that, MIG/MAG comparative welds were carried out at both polarities, using two shielding gas blends and two current values. The transfer mode and arc behavior were assessed by synchronized shadowgrafy technique. The bead geometry was evaluated through metallographic procedures. From the results, which does not agree entirely with the current literature, it was observed that as much the transfer mode as the bead morphology and finish depend on the shielding gas composition. To explain the phenomena inherent to a higher fusion rate at CC-, it is claimed that the fact of the arc to climb the wire surface at this polarity is the governing factor.

Uma das principais vantagens do processo MIG/MAG é a alta produtividade. Na maioria das aplicações utiliza-se a polaridade positiva, devido a maior estabilidade do arco, geração de menos respingos e formação de cordões com geometria adequada. No entanto, em algumas aplicações, se demanda uma maior capacidade de produção do que a que o MIG/MAG convencional oferece. Na literatura é citado que a polaridade negativa proporciona maior taxa de fusão do que a positiva, apesar de levar à grande produção de respingos e formação inadequada do cordão. Lamentavelmente, não há muita informação disponível sobre os efeitos das variáveis do processo nessa polaridade, tão pouco justificativas sobre tal. Assim, neste trabalho se procurou entender a razão para que uma maior taxa de deposição aconteça na polaridade negativa, assim como o respectivo efeito sobre a geometria dos cordões. Para isto, foram realizadas soldagens MIG/MAG comparativas na polaridade positiva e negativa, usando duas composições de gases de proteção em dois valores de corrente. O modo de transferência e o comportamento do arco foram analisados por perfilografia sincronizada. O perfil geométrico do cordão foi avaliado por meio de procedimentos metalográficos. A partir dos resultados, que discordam em parte da literatura corrente, foi observado que tanto o modo de transferência como a morfologia e aspecto do cordão são dependentes da composição do gás de proteção. Para explicar os fenômenos inerentes à maior taxa de fusão do arame em CC-, sugere-se que o fato de o arco escalar as laterais do arame nesta polaridade seja o fator governante. One of the main advantages of the MIG/MAG process is its high productivity. Usually, the positive polarity is employed, due to a higher arc stability, less spattering and adequate bead profiles. However, a higher production capacity than observed in the conventional MIG/MAG process has been demanded for some applications. In the current literature related to MIG/MAG, it is mentioned that the negative polarity provides a higher fusion rate than the positive one, despite of leading to higher spattering and bead misshapen. Unfortunately, there is no much information available about the effects of process variables in this polarity, as much as concerning justifications. Thus, in this work was attempted to understand the reasons for a higher fusion rate at CC-, as well as the respective effect on the bead geometry. For that, MIG/MAG comparative welds were carried out at both polarities, using two shielding gas blends and two current values. The transfer mode and arc behavior were assessed by synchronized shadowgrafy technique. The bead geometry was evaluated through metallographic procedures. From the results, which does not agree entirely with the current literature, it was observed that as much the transfer mode as the bead morphology and finish depend on the shielding gas composition. To explain the phenomena inherent to a higher fusion rate at CC-, it is claimed that the fact of the arc to climb the wire surface at this polarity is the governing factor.

A soldagem de ligas de alumínio sem degradação excessiva das propriedades originais do metal base apresenta-se como um obstáculo a ser superado pelas indústrias em seus processos de fabricação, uma vez que o alumínio tem sido usado cada vez de forma mais intensiva. Neste sentido, o processo de soldagem denominado Friction Stir Welding (FSW) tem recebido atenção por suas potencialidades onde o aporte de calor deve ser minimizado ou quando metais dissimilares devem ser soldados. Neste processo, uma ferramenta de alta resistência mecânica e com um perfil especial é utilizada para, por meio de atrito com as peças a serem soldadas, gerar calor e misturar mecanicamente o material da junta, consolidando a solda. Este trabalho visa implementar o processo FSW utilizando uma fresadora universal de elevada rigidez na soldagem de chapas de alumínio AA 5052-H34 com 6,35mm de espessura. Para tanto, três geometrias de ferramentas de soldagem foram projetadas, fabricadas e testadas, de forma a definir-se parâmetros de soldagem compatíveis com as condições fornecidas pela máquina fresadora, por meio de testes preliminares. Definidos estes parâmetros, juntas foram obtidas com as três geometrias de ferramenta disponíveis e seus desempenhos foram comparados. Ensaios mecânicos de dobramento e tração, medição do perfil de microdurezas e análise macrográfica da seção transversal das soldas foram os métodos empregados na caracterização das propriedades resultantes. Em adição, soldas pelo processo MIG também foram obtidas e sujeitas às mesmas avaliações. considerando-se a tensão de escoamento como parâmetro de comparação, as três geometrias testadas apresentaram desempenho similar (em torno de 80% da tensão de escoamento do metal base). Porém, se comparadas com respeito aos valores de ductilidade ou aos testes de dobramento transversal, observou-se que uma das geometrias testadas tem desempenho inferior às demais devido a presença de uma descontinuidade longitudinal no cordão de solda. O perfil de microdureza das amostras soldadas pelo processo FSW demonstrou homogeneidade entre as diferentes zonas microestruturais existentes ao longo da seção transversal, ao passo que as amostras soldadas através do processo MIG apresentaram variação característica dos processos ao arco elétrico.Welding of aluminum alloys with no considerable degradation of the properties of the base metal is a problem to be overcomed by industry manufacturing processes. In the aeronautical industry, no-melt joining processes such as adhesive bonding or riveting are often considered when designing aluminum connections. Alternatively, a welding process named Friction Stir Welding (FSW) is receiving crescent attention for its potential applications where heat input shall be minimized or when dissimilar metals must be joined. In this process a high strength rotating tool with a special profile is introduced at the interface of the materials to be joined and translated along the joint at controlled speeds. Heat generated softens the material and allows the tool to stir while traveling along the joint. This work aimed to product welds on AA 5052-H34 plates, 6.35mm (0,25 inches) thickness, using a conventional milling machine. In order to do that, three tool geometries were designed, manufactured and tested so as to define which welding parameters could generate the best results. Once these parameters were chosen, each tool produced three welds and their performance was evaluated. Transversal bending, tensile tests, micro-hardness measurements along the weld cross-section and macrographical analysis were carried out in order to assess weld properties. In addition, MIG welds were produced and subjected to the same test conditions. Considering yield stress as an efficiency parameter, all the tested tools presented similar results (around 80% of the base metal yield stress). However one of these tools showed inferior performance when considering elongation or transversal bending test as a comparison parameter due to the presence of a longitudinal groove, as observed in macrographical analysis. FS welded samples have not showed considerable variation along the different microstructure zones in micro-hardness measurements, while MIG welds presented well defined zones as characteristic to electric-arc processes.

A utilização de corrente pulsada para a soldagem MIG do alumínio, apesar de ser uma das tecnologias mais indicadas, em virtude de proporcionar melhores resultados, apresenta dificuldades no início do processo, principalmente no que concerne à abertura do arco. Visando desenvolver um processo mais adequado de abertura do arco, foram estudadas duas novas técnicas: a primeira baseada na imposição de elevada corrente, combinada à interrupção do avanço do arame, e uma segunda, com aplicação de baixa corrente, associada ao recuo do arame, que demandou o aperfeiçoamento do cabeçote alimentador de arame. A primeira técnica, apesar de assegurar a ignição do arco, resultou em duas formas de abertura condicionadas à geometria da ponta do arame. Uma delas é explosiva com ignição próxima ao comprimento médio do arame eletrodo, e outra suave com ignição próxima ao ponto de contado do arame eletrodo com o metal de base. A segunda técnica, independentemente da geometria da ponta do arame, promoveu abertura suave, com baixo aporte térmico e ignição do arco sempre próxima ao ponto de contado do arame eletrodo com o metal de base, sendo considerada mais adequada que a primeira. The use of pulsed current in aluminum Gas Metal Arc Welding (GMAW-P), despite to be one of the most indicated technology for providing excellent results, it presents serious arc starting problems, sometimes resulting in starting arc process failure. In order to develop a guaranteed arc initiation process, two techniques were considered and examined: the first using high current level associated to wire feed stopping, and a second using low current level associated to wire return, to which a wire feeder development was carried out. Conditioned by the wire tip geometry the first technique, although assures the arc initiation, it is obtained by two different ways, an exploded ignition close to the wire middle length, or a soft ignition close to the wire tip contact with work piece. The second technique, for any wire tip geometry, assured soft arc ignition, low heat input and ignition always close to the wire tip contact with work piece, Being considered more appropriate than the first.

A utilização de corrente pulsada para a soldagem MIG do alumínio, apesar de ser uma das tecnologias mais indicadas, em virtude de proporcionar melhores resultados, apresenta dificuldades no início do processo, principalmente no que concerne à abertura do arco. Visando desenvolver um processo mais adequado de abertura do arco, foram estudadas duas novas técnicas: a primeira baseada na imposição de elevada corrente, combinada à interrupção do avanço do arame, e uma segunda, com aplicação de baixa corrente, associada ao recuo do arame, que demandou o aperfeiçoamento do cabeçote alimentador de arame. A primeira técnica, apesar de assegurar a ignição do arco, resultou em duas formas de abertura condicionadas à geometria da ponta do arame. Uma delas é explosiva com ignição próxima ao comprimento médio do arame eletrodo, e outra suave com ignição próxima ao ponto de contado do arame eletrodo com o metal de base. A segunda técnica, independentemente da geometria da ponta do arame, promoveu abertura suave, com baixo aporte térmico e ignição do arco sempre próxima ao ponto de contado do arame eletrodo com o metal de base, sendo considerada mais adequada que a primeira.The use of pulsed current in aluminum Gas Metal Arc Welding (GMAW-P), despite to be one of the most indicated technology for providing excellent results, it presents serious arc starting problems, sometimes resulting in starting arc process failure. In order to develop a guaranteed arc initiation process, two techniques were considered and examined: the first using high current level associated to wire feed stopping, and a second using low current level associated to wire return, to which a wire feeder development was carried out. Conditioned by the wire tip geometry the first technique, although assures the arc initiation, it is obtained by two different ways, an exploded ignition close to the wire middle length, or a soft ignition close to the wire tip contact with work piece. The second technique, for any wire tip geometry, assured soft arc ignition, low heat input and ignition always close to the wire tip contact with work piece, Being considered more appropriate than the first.

The present study examined the pathogenesis of interstitial inflammation and fibrosis in antihypertensively treated rats with two-kidney, one-clip hypertension. Hypertensive rats were randomized into four groups: no treatment and moderate, intermediate, and intensified lowering of blood pressure with increasing doses of a vasopeptidase inhibitor for 6 wk. The vasopeptidase inhibitor dose dependently lowered blood pressure. The tubulointerstitial damage was accompanied by a diffuse infiltration of mononuclear cells and circumscript mononuclear inflammatory cell cluster formation consisting mainly of T cells and to a lesser degree of macrophages and B cells. Real-time PCR analyses showed a dose-dependent induction of MCP-1 and the Th1-type chemokines IP10 and Mig as well as their receptor CXCR3 and the Th1 cytokine IFN-γ. In situ hybridization and laser microdissection revealed a strong expression of these Th1-associated transcripts in the clusters and, in the case of MCP-1, also diffusely in the interstitium. The inflammation was accompanied by the appearance of myofibroblasts and synthesis of the fibrogenic factor plasminogen activator inhibitor-1 as well as the collagenase matrix metalloproteinase-2, leading to collagen I upregulation and interstitial scarring. No inflammation or fibrosis was found in normotensive rats treated with the vasopeptidase inhibitor. The renal injury in the clipped kidney is accompanied by compartment-specific chemokine expression and cell cluster formation of Th1 specificity associated with upregulation of fibrogenic proteins and matrix metalloproteinases. These findings suggest that the Th1 chemokines IP10 and Mig as well as their receptor CXCR3 are potential targets for therapeutic interventions in ischemic nephropathy.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Em muitos casos o passe de raiz é uma etapa crítica da soldagem, uma vez que sua execução é afetada por diversos fatores, tais como variação da abertura da junta, ângulo do chanfro, dimensões da face (nariz) da raiz, inclinação da tocha, velocidade de soldagem e velocidade de alimentação. Além disso, a escolha do processo de soldagem é um fator primordial para garantir a execução de um passe de raiz com adequadas propriedades mecânicas e metalúrgicas. Nesse contexto, este trabalho teve como objetivo estudar a viabilidade dos processos de soldagem MIG-P CC+ e TIG-A aplicado ao passe de raiz em chapas de 200 x 200 x 12,75 mm da liga de alumínio AA 5052. Para tal, foram analisadas configurações diferentes de soldagem: o tipo de chanfro (em V e em gola com L=2,00 e 3,00 mm) e dois tipos de metais de adição (ER 4043 e 5356). Como metodologia de comparação, foi determinada a mesma corrente de 150 A e taxa de deposição do metal de adição Va/Vs = 14, foram realizadas 8 combinações de parâmetros, cada uma com 3 repetições, totalizando 24 testes, salientando que foi usada apenas a configuração de chanfro mais adequada para o TIG-A. São apresentados resultados da micrografia e microdureza das zonas fundida e termicamente afetada e níveis de diluição para as juntas soldadas com os distintos metais de adição, além da radiografia. Nas condições estabelecidas neste trabalho, pode-se afirmar que o processo TIG-A apresentou melhores resultados em relação ao MIG-P CC+. Em relação à configuração do chanfro, o que se mostrou mais adequado foi o chanfro em V, para ambos os metais de adição e processos. Não ocorreram defeitos como falta de fusão, mordeduras e rugosidades. Em relação aos níveis de diluição, foram constatados maiores valores quando utilizado o processo MIG-P CC+ para o ER 4043, assim como o processo TIG-A na configuração de chanfro em V. O metal de adição ER 4043 apresentou uma quantidade de poros maior em relação ao ER 5356, em ambos os processos. Foi observada à presença de um refino de grão, além de maiores níveis de dureza em todas as soldas realizadas com o metal de adição ER 5356. In many cases the root pass is a critical step of welding, since its execution is affected by several factors, such as variation of joint opening, chamfer angle, dimensions of the face (nose) root, torch inclination, welding speed and feed speed. Moreover, the choice of the welding process is a key factor to ensure the execution of a root pass with adequate mechanical and metallurgical properties. In this context, this work aimed to study the feasibility of MIG-P CC+ and TIG-A welding processes applied to the root pass in plates of 200 x 200 x 12,75 mm of the AA 5052 aluminum alloy. For this, different configurations of welding were analyzed: chamfer type(V and collar with L=1,0 and 3,00 mm) and two types of addition metals (ER 4043 and 5356). As compared methodology, It was determined the same current 150 A and the deposition rate of addition metal Va/Vs = 14, they were proposed 12combinations of parameters, each with 3repetitions, totaling 36 tests, stressing that It was used only the most appropriate chamfer setting for TIG-A. Results of micrograph and microhardness of fusion and heat affected zones and dilution levels for welded joints with diferente addition metals, beyond radiography. At the established conditions in this work, it can be said that the TIG-A process showed better results in relation to MIG-P CC+. About the chamfer configuration, which was more appropriate was V chamfer, for both addition metals and process. There were no defects such as lack of fusion, bites and roughness. Relative to dilution levels, higher values were observed when used the MIG-P CC+ process for the ER 4043, as well as TIG-A in the V chamfer configuration. ER 4043 addition metal showed a larger amount of pores in relation to the ER 5356, in both process. It was observed the presence of a grain refining, beyond higher hardness levels in all welds made with the ER 5356 addition metal.

Submitted by Helga Morais (helga.morais@estsetubal.ips.pt) on 2015-12-01T10:31:58Z No. of bitstreams: 1 Dissertação_Mestrado_ESTSetúbal_MIG - 26-11-2015.pdf: 4721093 bytes, checksum: d96948110a0cb09cb43e0d62805fe440 (MD5) Made available in DSpace on 2015-12-01T10:31:58Z (GMT). No. of bitstreams: 1 Dissertação_Mestrado_ESTSetúbal_MIG - 26-11-2015.pdf: 4721093 bytes, checksum: d96948110a0cb09cb43e0d62805fe440 (MD5) Previous issue date: 2015-07

Nos tempos que decorem, em que os recursos são cada vez mais escassos, as atividades de auditoria revelam-se como meio de determinar e garantir a eficiência, eficácia e qualidade operacional e financeira das organizações em geral, em particular das instituições bancarias. Deste contexto emerge a necessidade das instituições adotarem uma posição proactiva e facilitadora no que as atividades de auditoria diz respeito. Neste sentido, habilitar as equipas de auditoria co medidas sistematizadas cuja aplicação é apoiada por ferramentas tecnológicas que lhes permita planear, executar e monitorizar numa perspetiva de continuidade as ações de auditoria constitui o objetivo geral deste trabalho. Adotando uma abordagem de caso de estudo definiram-se as necessidades/requisitos que informam a proposta apresentada. Assim, o presente trabalho é consubstanciado na proposta duma framework que modela uma sistematização do ciclo de vida das auditorias no seu sentido mais lato, sendo que as principais contribuições deste redundam: 1) na conceptualização de um modelo de acompanhamento e monitorização contínua do ciclo de vida das ações de auditoria, 2) a sua integração numa abordagem de modelação multidimensional de dados, que em conjunto permitem uma otimização do trabalho e uma orientação para o desenvolvimento de ferramentas de suporte. Constitui-se ainda âmbito do presente trabalho o desenvolvimento dum protótipo ilustrativo de uma ferramenta. Para efeito de avaliação elaborou-se um questionário que foi submetido a peritos/técnicos em auditoria, permitindo aferir que o modelo criado é útil/aplicável e a sua adoção habilita os auditores com critérios específicos e indicadores que permitem quantificar, qualificar e/ou avaliar performance de produtos, serviços e unidades orgânicas afetos às ações de auditoria. Os resultados da avaliação revelam uma perspetiva satisfatória dos peritos/auditores inquiridos em relação a contribuição do presente trabalho.

Background Asthma is a disease encompassing a variety of contributing factors. Phenotyping of asthma based on the profile of accumulated granulocytes in the airways has been performed to explore the mediators involved in allergic bronchial inflammation. The aim of this study was to clarify the characteristics of the CXC chemokine superfamily induced by IFN-γ, namely CXCR3 ligands, in the airways of patients with asthma stratified by the differential proportion of granulocytes in sputum. Methods Sputum was induced in 39 adult patients with asthma and 12 healthy subjects. Sputum samples were analyzed for total cell counts and differentials, and concentrations of IFN-γ–inducible protein 10 kDa (IP-10, CXCL10), monokine induced by IFN-γ (Mig, CXCL9), IFN-inducible T cell a chemoattractant (I-TAC, CXCL11), and IL-8 in the supernatants were assayed by ELISA. Results Sputum concentrations of IP-10, Mig, and IL-8 were significantly higher in asthma than in healthy subjects. IP-10, Mig, and IL-8 were significantly higher in the mixed granulocyte subtype (eosinophils ≥ 2 % and neutrophils ≥ 40 % in sputum) than in healthy subjects. Additionally, IP-1 0 was significantly higher in the mixed granulocyte subtype than in eosinophil-predominant or neutrophil-predominant subtype (eosinophil percentage ≥ 2 % or neutrophil percentage ≥ 40 %). Mig and IL-8 were significantly higher in the mixed granulocyte subtype than in the paucigranulocyte subtype (eosinophils

The welding of metal matrix material reinforced with ceramic particles has some problems such as formation of oxide layer, segregation occurring on welding area, and reaction of ceramic particles with welding bath. The expected mechanical properties cannot be obtained because of these problems. In this study, the weldability of aluminum 2014 alloy reinforced with SiC particles was investigated. MIG welding process was used via using AlSi5 alloy wire at different types and values of welding currents. Samples obtained using manual welding current were compared to those obtained using pulse welding current, in terms of microstructure and distribution of hardness. The effects of different types and values of welding currents on the microstructure and hardness distribution were examined. It was obtained that the welding of the composite with aluminum 2014 alloy matrix reinforced with SiC particles via using of pulse current, potential formation of segregation was prevented and microstructural properties were improved.

U ovom radu opisan je način kako konfigurirati ABB robotsku ruku IRB140 da odrađuje posao zavarivanja. Navedene su prednosti i nedostaci tog postupka. Simulacija se izrađuje u programskom alatu navedene tvrtke ABB. Zavarivanje je izvršeno na pokaznom modelu loga Visoke tehničke škole u Bjelovaru. Model je izrađen u CAD programskom alatu SolidWorks. Korišteni alat za zavarivanje je PKI 500 pištolj za MIG tehnologiju zavarivanja. Nosivi stol za robotsku ruku i model, također su izrađeni u CAD programskom alatu SolidWorks. Korišten je modul Weldment, te nosivi elementi stola načinjeni su od aluminijskih profila AlSigma 45x45. Dobiven je prikaz potpuno automatiziranog procesa zavarivanja sa velikom točnošću.

Titel: Sjuksköterskors upplevelse av att arbeta med hastigt försämrade patienter efter genomförd ALERT-utbildning Bakgrund: Patienter som fått hjärt- och/eller andningsstillestånd på vårdavdelningar och som läggs in på intensivvårdsavdelning (IVA) har haft försämrade vitalparametrar redan 6-8 timmar innan ankomst till IVA. 50 % av dessa inläggningar hade kunnat förhindras om personalen på avdelningen haft rätt kunskap i att upptäcka varningssignaler och hur de åtgärdas. ALERT-utbildningen uppmuntrar till användandet av ett enkelt verktyg för bedömningen av patienter, vilket leder till ökat självförtroende och minskad ångest i hanteringen av akut sjuka patienter och intensivvård kan undvikas eller sättas in i rätt tid. Syfte: Att undersöka sjuksköterskors upplevelse av att arbeta med hastigt försämrade patienter efter genomförd ALERT-utbildning Metod: Intervjuer med tolv allmänsjuksköterskor på kirurgisk och medicinsk vårdavdelning. Insamlad data analyserades med kvalitativ innehållsanalys. Resultat: Vid analys av texten framkom totalt tre övergripande teman; Ökad förmåga till tidigare varseblivning, Känsla av ökad trygghet i sjuksköterskerollen och Upplevelse av ökad patientsäkerhet. Dessa teman mynnade ut i sex subteman; Tidiga varningssignaler uppmärksammas, Kontroller samt åtgärd vid hastig försämring, Ökat självförtroende, Viktigt med repetition, Struktur ger säkerhet i arbetet samt Sjuksköterskornas stöd för att bedöma olika vitalparametrar. Slutsats: Sjuksköterskorna upplever att ALERT-utbildningen ökar deras självförtroende och höjer patientsäkerheten, samt att regelbundna repetitioner är viktigt för att upprätthålla kunskapen.

Hybrid welding of stainless steels or aluminium alloys was performed with the heat sources of YAG laser and TIG, or YAG laser and MIG, respectively. The effects of welding conditions and melt flows on penetration depth, geometry and porosity formation were investigated with the X-ray transmission real-time observation method. Melt flows on penetration depth and geometry were consequently confirmed. Concerning porosity suppression, in TIG-YAG hybrid welding of stainless steel, no formation of bubbles was attributed to the absence of pores. On the other hand, disappearance of bubbles from the concave molten pool surface due to the arc pressure played an important role in reducing porosity in YAG-MIG hybrid welding of aluminium alloys at high arc currents.

U teorijskom dijelu rada navedeno je označavanje aluminijskih legura s obzirom na legirne elemente i stanja u kojima se nalaze, te glavna podjela sa svojstvima aluminijskih legura prema toplinskoj obradivosti. Opisani su postupci zavarivanja aluminijskih legura s naglaskom na TIG i MIG postupak koji se najviše primjenjuju, navedeni su zaštitni plinovi, te izbor dodatnih materijala koji bitno utječe na svojstva zavarenih spojeva. Analizirana je zavarljivost toplinski obradivih aluminijskih legura, te su opisane osnovne karakteristike zavarenih spojeva i glavni mehanizmi koji narušavaju mehanička svojstva i integritet spojeva. Navedena je primjena aluminijskih legura s primjerima iz proizvodnje. U eksperimentalnom dijelu odabrana je prikladna tehnologija zavarivanja aluminijske legure AW 6082 i dodatni materijali kojima bi se reduciralo smanjenje čvrstoće i pojava pukotina u zavarenim spojevima. Provedeno je sučeono zavarivanje radnih komada impulsnim MIG postupkom zavarivanja s ciljem usporedbe dva različita dodatna materijala, ER4043 i ER5356. Na zavarenim uzorcima provedena su mehanička ispitivanja, na savijanje i statički vlačni pokus, te su obavljene makroanaliza i mikroskopska analiza uzoraka s ciljem uvida u strukturu i svojstva zavarenih spojeva. U konačnici su donijeti zaključci o mogućim alternativama tehnologije i dodatnim materijalima kojima bi se poboljšala mehanička svojstva zavarenog spoja. The theoretical part of this thesis covers the designation of aluminum alloys according to their conditions, alloying elements and in respect to their heat treatability. The thesis also covers the procedures of welding aluminum alloys with emphasis on TIG and MIG processes, shielding gases and a selection of filler materials which have a significant impact on welded joints properties. Weldability of heat treatable aluminum alloys has been analyzed and even basic characteristics of welded joints and mechanisms that may impair mechanical properties and integrity of some alloys have been covered along with the usage of aluminum alloys supported by practical examples. A suitable welding technology has been chosen for welding aluminum alloy AW 6082 together with filler materials which would reduce strength and the occurrence of cracks in the welded joints. Using the pulse MIG procedure, workpieces have been butt welded in order to compare filler materials ER4043 and ER5356. A variety of tests were carried out on the welded specimens like mechanical tests, bending and tension tests together with macro and micro analysis with the purpose of gaining insight into the structure and properties of welded joints. At the end, conclusions about possible alternative technologies and filler materials which could enhance the mechanical properties of welded joints have been brought to light.