bluuebunny/crossref_metadata_2025 huggingface dataset:
Elevated high-sensitive troponin T on admission is an indicator of poor long-term outcome in patients with subarachnoid haemorrhage: a prospective observational study
Authors: Oras Jonatan , Grivans Christina , Bartley Andreas , Rydenhag Bertil , Ricksten Sven-Erik , Seeman-Lodding Helene
Published: January 2016

Background

Patients with subarachnoid haemorrhage (SAH) frequently develop cardiac complications in the acute phase after the bleeding. Although a number of studies have shown that increased levels of cardiac biomarkers after SAH are associated with a worse short-term prognosis, no prospective, consecutive study has assessed the association between biomarker release and long-term outcome. We aimed to evaluate whether the cardiac biomarkers, high-sensitive troponin T (hsTnT) and N-terminal pro B-type natriuretic peptide (NTproBNP), were associated with poor 1-year neurological outcome and cerebral infarction due to delayed cerebral ischaemia (CI-DCI).

Methods

In this single-centre prospective observational study, all consecutive patients admitted to our neurointensive care unit from January 2012 to December 2013 with suspected/verified SAH with an onset of symptoms <72 hours were enrolled. Blood samples for hsTnT and NTproBNP were collected during three consecutive days following admission. Patients were followed-up after 1 year using the Glasgow Outcome Scale Extended (GOSE). Poor neurological outcome was defined as GOSE ≤4.

Results

One hundred and seventy seven patients with suspected SAH were admitted during the study period; 143 fulfilled inclusion criteria and 126 fulfilled follow-up. Forty-one patients had poor 1-year outcome and 18 had CI-DCI. Levels of hsTnT and NTproBNP were higher in patients with poor outcome and CI-DCI. In multivariable logistic regression modelling age, poor neurological admission status, cerebral infarction of any cause and peak hsTnT were independently associated with poor late outcome. Both peak hsTnT and peak NTproBNP were independently associated with CI-DCI.

Conclusion

Increased serum levels of the myocardial damage biomarker hsTnT, when measured early after onset of SAH, are independently associated with poor 1-year outcome. Furthermore, release of both hsTnT and NTproBNP are independently associated with CI-DCI. These findings render further support to the notion that troponin release after SAH is an ominous finding. Future studies should evaluate whether there is a causal relationship between early release of biomarkers of myocardial injury after SAH and neurological sequelae.
High incidence of adverse events during intra-hospital transport of critically ill patients and new related risk factors: a prospective, multicenter study in China
Authors: Jia Liu , Wang Hongliang , Gao Yang , Liu Haitao , Yu Kaijiang
Published: January 2016

Background

The aim of the present study was to investigate the incidence of adverse events (AEs) during intra-hospital transport (IHT) of critically ill patients and evaluate the risk factors associated with these events.

Methods

This prospective multicenter observational study was performed in 34 intensive care units in China during 20 consecutive days from 5 November to 25 November 2012. All consecutive patients who required IHT for diagnostic testing or therapeutic procedures during the study period were included. All AEs that occurred during IHT were recorded. The incidence of AEs was defined as the rate of transports with at least one AE. The statistical analysis included a description of demographic and clinical characteristics of the cohort as well as identification of risk factors for AEs during IHT by univariate and multivariate logistic regression analyses.

Results

In total, 441 IHTs of 369 critically ill patients were analyzed. The overall incidence of AEs was 79.8 % (352 IHTs). The proportion of equipment- and staff-related adverse events was 7.9 % (35 IHTs). The rate of patient-related adverse events (P-AEs) was 79.4 % (349 IHTs). The rates of vital sign–related P-AEs and arterial blood gas analysis–related P-AEs were 57.1 % (252 IHTs) and 46.9 % (207 IHTs), respectively. The incidence of critical P-AEs was 33.1 % (146 IHTs). The rates of vital sign–related critical P-AEs and arterial blood gas analysis–related critical P-AEs were 22.9 % (101 IHTs) and 15.0 % (66 IHTs), respectively. All data collected in our study were considered potential risk factors. In the multivariate analysis, predictive factors for P-AEs were pH, partial pressure of carbon dioxide in arterial blood, lactate level, glucose level, and heart rate before IHT. Furthermore, the Acute Physiology and Chronic Health Evaluation II score, partial pressure of oxygen in arterial blood, lactate level, glucose level, heart rate, respiratory rate, pulse oximetry, and sedation before transport were independent influential factors for critical P-AEs during IHT.

Conclusions

The incidence of P-AEs during IHT of critically ill patients was high. Risk factors for P-AEs during IHT were identified. Strategies are needed to reduce their frequency.

Trial registration

Chinese Clinical Trial Register identifier ChiCTR-OCS-12002661. Registered 5 November 2012.
Multipotent mesenchymal stromal cells from patients with newly diagnosed type 1 diabetes mellitus exhibit preserved in vitro and in vivo immunomodulatory properties
Authors: Yaochite Juliana Navarro Ueda , de Lima Kalil Willian Alves , Caliari-Oliveira Carolina , Palma Patricia Vianna Bonini , Couri Carlos Eduardo Barra , Simões Belinda Pinto , Covas Dimas Tadeu , Voltarelli Júlio César , Oliveira Maria Carolina , Donadi Eduardo Antônio , Malmegrim Kelen Cristina Ribeiro
Published: January 2016

Background

Type 1 diabetes mellitus (T1D) is characterized by autoimmune responses resulting in destruction of insulin-producing pancreatic beta cells. Multipotent mesenchymal stromal cells (MSCs) exhibit immunomodulatory potential, migratory capacity to injured areas and may contribute to tissue regeneration by the secretion of bioactive factors. Therefore, MSCs are considered as a promising approach to treat patients with different autoimmune diseases (AID), including T1D patients. Phenotypical and functional alterations have been reported in MSCs derived from patients with different AID. However, little is known about the properties of MSCs derived from patients with T1D. Since autoimmunity and the diabetic microenvironment may affect the biology of MSCs, it becomes important to investigate whether these cells are suitable for autologous transplantation. Thus, the aim of the present study was to evaluate the in vitro properties and the in vivo therapeutic efficacy of MSCs isolated from bone marrow of newly diagnosed T1D patients (T1D-MSCs) and to compare them with MSCs from healthy individuals (C-MSCs).

Methods

T1D-MSCs and C-MSCs were isolated and cultured until third passage. Then, morphology, cell diameter, expression of surface markers, differentiation potential, global microarray analyses and immunosuppressive capacity were in vitro analyzed. T1D-MSCs and C-MSCs therapeutic potential were evaluated using a murine experimental model of streptozotocin (STZ)-induced diabetes.

Results

T1D-MSCs and C-MSCs presented similar morphology, immunophenotype, differentiation potential, gene expression of immunomodulatory molecules and in vitro immunosuppressive capacity. When administered into diabetic mice, both T1D-MSCs and C-MSCs were able to reverse hyperglycemia, improve beta cell function and modulate pancreatic cytokine levels.

Conclusions

Thus, bone marrow MSCs isolated from T1D patients recently after diagnosis are not phenotypically or functionally impaired by harmful inflammatory and metabolic diabetic conditions. Our results provide support for the use of autologous MSCs for treatment of newly diagnosed T1D patients.
Remittances and child labor in Bolivia
Authors: Coon Michael
Published: January 2016

This article explores the effect of remittances on the prevalence and intensity of child labor in Bolivia. Using household survey data, we find that children in remittance-receiving households are less likely to be actively supplying labor, and the number of hours worked per week declines with the size of remittances received. The size of the impact varies between urban and rural households. Remittances to urban households have a larger impact on moving children completely out of the labor force, but a smaller increase in remittance size is needed for an equal reduction in number of hours worked in rural areas.

JEL codes: F24, O15, E26
President's Page
Authors: Abriel Bill
Published: January 2016

As this article is written, there is continued upheaval in the oil, gas, and mining sectors of the geophysical community. Commodity prices have dropped precipitously and have not recovered from a year of declines. The majority of the members and associates of the Society of Exploration Geophysicists are actively engaged in the extraction industry and have subsequently seen a substantial number of layoffs and major changes in company budgets as a result of the price downturn. And even though the industry may remember its history of booms and busts, this downturn is especially traumatic in terms of both severity and timing. The last major downturn was nearly 30 years ago, and the industry has been mostly stable since then.
Introduction to this special section: Resource plays II: Geophysics
Authors: Sayers Colin M. , Foster Doug , Yenugu Malleswar
Published: January 2016

In resource plays, hydrocarbons usually are present over a large area so that the geologic risk of not finding hydrocarbon in such plays is low. Examples of resource plays include shale-gas reservoirs, tight oil and gas reservoirs, coalbed methane, and so forth. Because of the low permeability of such reservoirs, lateral wells and hydraulic fracturing often are used. However, production from wells in such plays often shows considerable lateral variation, and a randomly placed well might not be profitable. Geophysical methods are, therefore, of great interest for identifying sweet spots and optimizing well placement. Economic production from such formations requires good reservoir quality (RQ), representing the multiple properties defining reservoir potential, and good completion quality (CQ), representing the multiple properties defining the potential for creating and sustaining large surface area in contact with the reservoir (Suarez-Rivera et al., 2011).
Integration of completion data, microseismic data, downhole logs, and multicomponent seismic data in the Mississippi Lime, north-central Oklahoma
Authors: Singleton Scott , Chi Shihong , Lapaire Crystal , Sanford Lisa , Constance Paul
Published: January 2016

Previously published work on a Mississippi Limestone (Mississippi Lime) prospect in north-central Oklahoma described a prospect that is data rich. Aquisition was on a dense grid using nodal 3C phones, and PP and PS data were both processed and jointly inverted. Several pilot holes and laterals were drilled and fully logged, including Sonic Scanner and formation-microimager (FMI) fracture logs. Microseismic data were acquired on one well pad, as was a 3D VSP. New resesarch discusses two specific fracture-characterization methodologies. The first is the integration of vertical and lateral log suites, including fracture imaging, with seismic rock properties and completion results, including microseismic data. The results of this effort not only characterize fracture width and height but go farther by explaining why and how those fractures are created. The second is the use of converted-shear (PS) data to measure anisotropy and correlate those measurements with fracture logs. Specifically, two methods of calculating anisotropy are analyzed: slow shear-wave (S2) traveltime correction and transverse/radial energy ratio. Both methods are theoretically valid but might break down in practice because of various nongeologic artifacts that can be present in the data.
Sensitivity of P- and S-impedance to the presence of kerogen in the Eagle Ford Shale
Authors: Sayers Colin M. , Fisher Kevin , Walsh John J.
Published: January 2016

The amplitude variation with offset (AVO) of seismic waves reflected from an interface between two geologic layers is a function of the P-velocity, S-velocity, and density of the layers and can be used to obtain information on lithology, porosity, fluid content, and other formation parameters. Density, however, often is poorly resolved. Parameterization of AVO in terms of P-impedance, S-impedance, and density is better than parameterization in terms of P-velocity, S-velocity, and density because uncertainty in the density estimate has a greater impact on errors in estimates of P- and S-velocity than on errors in P- and S-impedance. For this reason, quantitative seismic interpretation makes use of rock-physics templates formulated in terms of P- and S-impedance. An investigation of the ability of rock-physics templates to distinguish between organic-rich and organic-lean shales uses log data from the Eagle Ford Shale and shows the effect of kerogen on in situ stress determination.
Fractal behavior of total organic carbon in shale-gas reservoirs with an example from the Barnett Shale, Texas, USA
Authors: Ouadfeul Sid-Ali , Aliouane Leila
Published: January 2016

The behavior of fractal analysis using the continuous wavelet transform in shale-gas reservoirs is studied based on estimation of the so-called Hölder exponent by analyzing a total-organic-carbon (TOC) well log using the continuous wavelet transform; the Morlet is the analyzing wavelet. Application to the TOC well-log data of a horizontal well drilled in the Fort Worth Basin, Texas, USA, where the main objective is the lower Barnett Shale, clearly shows no special behavior of the Hölder exponents for known sweet spots. This process can be applied to other well-log data of shale-gas reservoirs to compare results and generalize a rule about the fractal behavior in shale-gas reservoirs.
Rapid Determination of Trace Substance, 2-acetyl-1-pyrroline Content in Hom Mali Rice Using near Infrared Spectroscopy
Authors: Maneenuam Thararat , Chanprasert Wanchai , Rittiron Ronnarit , Prasertsak Anchalee , Wongpiyachon Sunanta
Published: January 2016

The analysis of 2-acetyl-1-pyrroline (2AP) content in Hom Mali rice by conventional method is time consuming, an experienced technician is needed and it is costly, therefore a reliable and rapid method for determining 2AP content in aromatic rice is required. The purpose of this study was to assess if the 2AP content in Hom Mali rice could be determined using near infrared (NIR) spectroscopy. A total of 205 ground samples with 2AP in the range 0.52–3.32 ppm were scanned by a Fourier-transform near infrared (FT-NIR) spectrometer in reflectance mode over the region 1100–2500 nm at room temperature (25–27°C). 2AP content was analysed by headspace-gas chromatography and used as the reference method. A model derived from this study was developed and the coefficient of determination ( R2), root mean square error of prediction ( RMSEP) and bias of the calibration equation were 0.79, 0.27 and 0.01 ppm, respectively. The calibration equation developed in this study could rapidly predict 2AP content and there was no significant difference between NIR-predicted values and actual values at a confidence interval of 95%. The calibration was based on ranges at 1409 nm and 1895 nm wavelengths which infer that the 2AP is linked to the lipid content of the samples. Therefore, it can be concluded that NIR spectroscopy can be used for the evaluation of 2AP content at the ppm level in Hom Mali rice.
The cardiac enigma: current conundrums in heart failure research
Authors: Kapiloff Michael S. , Emter Craig A.
Published: January 2016

The prevalence of heart failure is expected to increase almost 50% in the next 15 years because of aging of the general population, an increased frequency of comorbidities, and an improved survival following cardiac events. Conventional treatments for heart failure have remained largely static over the past 20 years, illustrating the pressing need for the discovery of novel therapeutic agents for this patient population. Given the heterogeneous nature of heart failure, it is important to specifically define the cellular mechanisms in the heart that drive the patient’s symptoms, particularly when considering new treatment strategies. This report highlights the latest research efforts, as well as the possible pitfalls, in cardiac disease translational research and discusses future questions and considerations needed to advance the development of new heart failure therapies. In particular, we discuss cardiac remodeling and the translation of animal work to humans and how advancements in our understanding of these concepts relative to disease are central to new discoveries that can improve cardiovascular health.
Referencing cross-reactivity of detection antibodies for protein array experiments
Authors: Lemass Darragh , O'Kennedy Richard , Kijanka Gregor S.
Published: January 2016

Protein arrays are frequently used to profile antibody repertoires in humans and animals. High-throughput protein array characterisation of complex antibody repertoires requires a platform-dependent, lot-to-lot validation of secondary detection antibodies. This article details the validation of an affinity-isolated anti-chicken IgY antibody produced in rabbit and a goat anti-rabbit IgG antibody conjugated with alkaline phosphatase using protein arrays consisting of 7,390 distinct human proteins. Probing protein arrays with secondary antibodies in absence of chicken serum revealed non-specific binding to 61 distinct human proteins. The cross-reactivity of the tested secondary detection antibodies points towards the necessity of platform-specific antibody characterisation studies for all secondary immunoreagents. Secondary antibody characterisation using protein arrays enables generation of reference lists of cross-reactive proteins, which can be then excluded from analysis in follow-up experiments. Furthermore, making such cross-reactivity lists accessible to the wider research community may help to interpret data generated by the same antibodies in applications not related to protein arrays such as immunoprecipitation, Western blots or other immunoassays.
Desafios do Ensino Superior para Estudantes de Escola Pública: um Estudo na UFLA
Authors: Alvarenga Carolina Faria , Sales Aline Pereira , Costa Adriano Dias da , Costa Maurício Donizete da , Veroneze Ricardo Braga , Santos Thiago Lima Bahia
Published: January 2016

Este trabalho busca compreender os desafios enfrentados por estudantes vindos de escolas públicas, por meio da análise do curso de Administração da Universidade Federal de Lavras, entre 2005 a 2010. Os resultados obtidos revelaram que a formação do estudante de escola pública é permeada por dificuldades, dentre as quais, destacam-se a falta de estrutura e recursos, a desmotivação dos professores, o desinteresse dos alunos, seja pelo cansaço físico ou pela falta de perspectivas para o futuro. Não obstante, o distanciamento com a universidade e a falta de divulgação das oportunidades existentes fazem do ensino superior uma realidade distante para a maioria desses estudantes. Ainda assim, muitos egressos do ensino público conseguem ter acesso ao ensino superior, sendo que, depois de inseridos, conseguem ter o mesmo padrão de aprendizagem daqueles que vieram de escola privada. Entretanto, continuam a enfrentar dificuldades que, até certo ponto, exigem ainda mais esforço destes estudantes.
A Mobilidade e a Gestão Intercultural nas Organizações
Authors: Craide Aline , Silva Floriano Barboza
Published: January 2016

Este ensaio teórico pretendeu analisar questões que envolvem a gestão intercultural nas organizações, além de demonstrar que a interculturalidade é uma das consequências da mobilidade de profissionais, assunto que perpassa o mundo do trabalho atualmente, seja no âmbito internacional ou intranacional. Sendo assim, inicialmente foi feita uma discussão teórica acerca de conceitos sobre mobilidade para, em seguida, descrever algumas questões que norteiam o conceito de interculturalidade. Identificou-se que a mobilidade de profissionais, seja internacional ou intranacional, oportuniza o encontro com um contexto culturalmente diverso em relação àqueles de suas origens.
Media training como ferramenta de vantagem competitiva
Authors: Souza Rosana Curvelo de , Añez Miguel Eduardo Moreno
Published: January 2016

O objetivo deste artigo é compreender a aptidão desenvolvida e as competências ressaltadas na aprendizagem em media training e verificar como elas podem, segundo os profissionais que ministram esse treinamento, gerar vantagem competitiva para os gestores e para a organização à qual servem. Os resultados das entrevistas realizadas com assessores de comunicação falam dos objetivos do treinamento, enunciam as habilidades consideradas imprescindíveis para que um gestor esteja apto a dar entrevistas e evidenciam a relação entre a preparação do gestor com a imagem organizacional. Também foi questionada a possível vantagem competitiva constituída para o gestor e sua carreira quando ele está habilitando, do ponto de vista de normas e procedimentos, a dar atender bem aos jornalistas e dar boas entrevistas.
Mercado de trabalho e a formação do administrador em uma IES pública em Recife-PE
Authors: Rio-Branco Raisa , Helal Diogo Henrique
Published: January 2016

Este artigo descreve o perfil dos estudantes de administração em Recife-PE, de uma IES pública, com ênfase para a análise de suas expectativas em relação ao mercado de trabalho. Realizou-se uma pesquisa descritiva a partir de dados primários, coletados a partir da aplicação de questionários. Os dados foram analisados a partir da perspectiva quantitativa. Os resultados indicam existir diferenças no perfil dos estudantes que estão ingressando na Universidade em relação aos concluintes. Os iniciantes são em maior número mulheres, com menor renda familiar, morenos e negros. Dentre os concluintes, há um percentual maior de empregados e estagiários, com renda mensal mais elevada. Ambos grupos esperam ser reconhecidos profissionalmente, após a formatura. Por fim, identificou-se que parte dos concluintes (24,7%) se mostrou desiludida com a preparação que o curso proporciona. Ambos os grupos, contudo, esperam ter salários mais elevados no futuro e um padrão de vida melhor.
Jogo de empresas interdisciplinar: elaboração e teste
Authors: Santoro Leonardo De Oliveira , Bouzada Marco Aurélio Carino
Published: January 2016

Este artigo buscou responder como deve ser e quais conceitos deve-se trabalhar em um jogo de empresas interdisciplinar que vise proporcionar experiência vivencial a estudantes no final de seus cursos superiores. Pretendeu-se verificar duas hipóteses: se a assimilação dos conceitos para os participantes do jogo foi superior à dos não participantes (H1); e se os participantes com melhores resultados no jogo também foram os que tiveram melhor assimilação dos conceitos (H2). Foram apresentadas a metodologia de coleta (através da aplicação-teste do jogo e de uma prova interdisciplinar junto a uma turma de graduação) e tratamento dos dados e as limitações da pesquisa. Após realizado um teste Mann-Whitney, a H1 foi confirmada. Quanto à H2, uma análise de correlação levou à sua rejeição. Com os resultados obtidos, o que se pode concluir é que o importante para o aprendizado é a participação no jogo e não o resultado em si.
Cultura e valores organizacionais em uma universidade federal brasileira
Authors: Ferreira Kamilla Alves Rodrigues , Moura Luiz Rodrigo , Cunha Nina Rosa Silveira , Moura Luiz Eduardo Leite de
Published: January 2016

Propõem-se dois objetivos: 1) apresentar as características culturais de três órgãos de um segmento de uma instituição pública, através de seus valores e orientações de cultura; 2) verificar se há diferenças entre os valores e as orientações culturais dos órgãos. O ambiente de pesquisa são os órgãos subordinados à Pró-Reitoria de Planejamento e Orçamento da Universidade Federal de Viçosa, em razão da importância das instituições de ensino no desenvolvimento social e econômico do País. Como pesquisa aplicada apresenta os valores e as orientações culturais de uma instituição pública, através da adaptação do Modelo de Análise Cultural Integrado, desenvolvido por Cercal (2001), Nelson e Loureiro (1996) e Trompenaars (1994). Verificou-se que há diferenças evidentes no relacionamento, no tempo e na forma de lidar com o ambiente. Concluiu-se que essas diferenças têm por base os valores praticados por seus integrantes, bem como às próprias características de cada órgão.
Quando o sapato aperta: competências emergentes na adversidade
Authors: Vasconcellos Sílvio Luís de , Garrido Ivan Lapuente , Calixto Cyntia Villasboas , Gonçalo Cláudio Reis
Published: January 2016

Este artigo procura identificar capacidades emergentes para formação de competências. Especificamente, busca entender como empresas de pequeno porte reorganizam estratégias diante da adversidade. Neste estudo, observou-se o redirecionamento estratégico de uma empresa de pequeno porte, prestadora de serviços em comércio exterior. O período analisado foi marcado por grandes mudanças no perfil de seus clientes, a maioria integrante do setor coureiro-calçadista, onde as empresas exportadoras galgaram mercados através da diferenciação. A empresa estudada passou a atuar como operadora logística, desencadeando mudanças em suas competências. A metodologia adotada foi o estudo de caso único. A escolha se deu por tratar-se de um caso de transformação dentro de um cluster ameaçado por concorrentes estrangeiros e pela acessibilidade às informações de um dos autores. Durante o estudo foi percebido um lento processo intuitivo de tomada de decisão. Ao final é apresentado um quadro comparativo entre os fundamentos teóricos e os dados empíricos.
A ética corporativa e o cenário competitivo: uma análise dos dilemas éticos nas relações de trabalho contemporâneas a partir do filme "O Corte" (Le Couperet)
Authors: Araujo Fábio Francisco de , Tomei Patricia Amélia
Published: January 2016

O fenômeno global contribuiu para a exclusão das fronteiras entre países e economias, impactando fortemente a sociedade contemporânea. Observa-se o surgimento de uma nova lógica para condução das atividades empresariais, que proporciona a formação de um ambiente altamente competitivo, onde se impõem novos modelos de relações de trabalho e dilemas éticos. Dessa forma, o presente artigo tem por objetivo analisar as mudanças nas relações de trabalho e os dilemas éticos impostos às organizações e aos profissionais que atuam numa sociedade global. A metodologia utilizada partiu da premissa de que as produções cinematográficas são reflexos de expressões culturais e abordam questões que contribuem para a análise de fenômenos reais. Ao estreitar as relações entre cinema e sociedade, os filmes exprimem o reflexo das crenças e valores dominantes na cultura. A seleção do filme francês O Corte (Le Couperet), como objeto de análise, na medida em que oferece uma visão oportuna sobre o mundo do trabalho e suas transformações nas modernas corporações. O filme parece sinalizar, assim, para os riscos apontados por autores como Ransome (1999) sobre o efeito corrosivo desses novos arranjos na crença do trabalho como fonte de realização das expectativas materiais e psicológicas dos indivíduos. O artigo aponta a discussão da ética corporativa como um instrumento útil aos membros da organização, visando reeducar os indivíduos para fazer com que os efeitos de um ambiente de alta competitividade sejam mitigados e, assim, buscar o equilíbrio entre a cooperação e a assertividade, respeitando os limites sociais e morais.
THE ASSESSMENT OF PROPERTIES FOR SELECTED FACTORS IN ABRASIVE WATER JET PROCESS
Authors: Sunova Anna , Sun Roman , Spišák Emil , Franková Mária
Published: January 2016

The article presents the current conditions of abrasive water jet cutting process and factors relative to the quality of cutting surface. The main goal of research was to evaluate the assessment of the cutting depth, corrugated bottom cutting edge and roughness of the specimens depending on selected factors such as cutting speed and abrasive amount in the abrasive water jet process. Specimen were cut in four phases as a square. Main results were that the distance between water jet entering and water jet leaving is decreased with the increasing abrasive amount and by following lower cutting rates. The increasing of a cutting rate negatively effects the quality of the cut surface and the size of the distance between water jet entering and water jet leaving, because the increasing of a cutting rate increases also values of the mentioned parameters. As to the distance between water jet entering and water leaving, the abrasive amount of 200-250 g.min-1 at the rate of 50 mm.min-1 is considered to be optimal, but outside this range the influence of the abrasive amount impacts negatively, primarily on water jet entering and water jet leaving that has a direct influence on the corrugated bottom cutting edge.
FAILURE OF COATINGS OF TINPLATES
Authors: Spišák Emil , Džupon Miroslav , Majerníková Janka , Spišáková Duľová Emília
Published: January 2016

The goal of the contribution was to perform the research about the way of failure of tin coatings and their causes and about behaviour of tin coatings at the limit states of deformation. The work shows that in the maximum plastic strain area the failure of tin coating was mainly due to transversal cracks without separation of the coating particles and decohesion at the coating-substrate interface. As an additional tin coating quality test, it would be advisable to include qualitative EDX analysis of tin coating in the area of uniform and maximum plastic strain of the surface of test specimens after a uniaxial tensile test.
MECHANICAL PROPERTIES LASER WELDING AUTOMOTIVE STEEL SHEETS
Authors: Lišková Anna , Mihaliková Mária , Dragošek Lukáš , Kočiško Róbert , Bidulský Róbert
Published: January 2016

The experimental and theoretical investigation deals with laser welding of automotive thin steel sheets. As tested materials were used Interstitial Free Steel (IF) from type of Hight Strength Low Alloy (HSLA) and the second is S420 steel (Micro-Alloyed Steel). Weld quality has been measured with the help of microhardness test and microstructure. Changes of properties of these materials were carried out by static conditions. The tensile properties of the welded samples have been set in the both longitudinal directions. The structure of welded joints these two materials were investigated by metallographic analysis. Metallographic analysis confirmed the formation of favourable structure of weld metal and heat affected zone. Obtained results showed that by laser welding it is possible to create the high quality welded joints with positive mechanical properties on used in automotive industry.
SHAPE AND SIZE ACCURACY OF 3D-PRINTED AlSi12 PARTS
Authors: Šafka Jiří , Mendřický Radomír , Ackermann Michal , Tuháček Daniel
Published: January 2016

This paper maps the topic of complex part production using Selective Laser Melting (SLM) technology. During the pre-processing part of the building process, it is crucial to choose the most suitable orientation of the model towards the building plate. It can be said that proper part placement can reduce the amount of support structures and the risk of model bending and following damage due to large thermal gradients. For this purpose, special specimens were printed on SLM280HL machine out of AlSi12 powder under different orientation towards the building plate and with different types of support structures. After finishing the building process, the influence of above described parameters to size and shape of the final product were evaluated. Accuracy of the final products was assessed thanks to contactless 3D scanner ATOS. Results of the work clearly show that if the model is positioned in such a manner that the least energy and thus heat generation is introduced into each layer, the lower the deformation of final part is.
MODELING AND VIBRATION ANALYSIS OF COMPLEX ANNULAR SYSTEM WITH USING CYCLIC SYMMETRY FEATURE
Authors: Noga Stanisław , Stachowicz Feliks
Published: January 2016

In the paper the free transverse vibration of representative toothed gear is considered. Analysed system is treated as an annular plate with complex geometry. The discussion is focused on using the cyclic symmetry modelling technique to vibration analysis of the system under the study. The method of creation of the toothed gear simplified FE model is proposed. The problems related to the determination of critical rotational speeds of the considered system are discussed. Campbell diagram for the studied system is elaborated and the method of designation of the safe working zone of the wheel is presented. Experimental investigations conducted in order to evaluate the proposed method of elaboration of FE models are presented. It is important to note that the issues presented in this work have a practical value for design engineers dealing with the dynamics of rotating systems.
EVALUATION OF LIMITING DRAWING RATIO (LDR) IN DEEP DRAWING PROCESS
Authors: Pernis Rudolf , Barényi Igor , Kasala Jozef , Ličková Mária
Published: January 2016

Part production by deep drawing technology brings important economic advantages. Cupping test is used to determine material suitability for deep drawing. The main principle of the test is redrawing of cylinder metal test piece to the cup. The result of the test is calculation of limiting drawing ratio (LDR) which states the ratio between the largest blank diameter and final cup diameter. Many cupping tests for various materials were performed in order to determine maximal value of LDR that would still allow deep drawing without failure of material integrity.Paper presents the theoretical determination of the limiting drawing ratio (LDR) in dependence on d0/t0 ratio and friction coefficient between blank and punch.Limiting drawing ratio (LDR) converges to Euler’s number (e) for high test piece depth and final cup diameter ratio values. Theoretical analysis of the cupping on drawing die with tractrix curve shows that maximal value of LDR may achieve value LDR>e. This is possible at lower values of test piece depth to final cup diameter ratio. Coefficient of friction has determining influence on LDR value.
CRYOMAK – THE OVERVIEW OF CRYOGENIC TESTING FACILITIES IN KARLSRUHE
Authors: Sas Jan , Weiss Klaus-Peter , Bagrets Nadezda
Published: January 2016

Since the field of cryogenic applications and testing has become very valuable, demand for material specification and improvements in this area has increased as well. One of the possibilities for the characterisation of cryogenic materials with a wide range of tests can be found at the Cryogenic Material Test Facility Karlsruhe (CryoMaK), within the Institute of Technical Physics (ITEP) at the Karlsruhe Institute of Technology (KIT). Skills, knowledge and best practices, related to cryogenic testing, have been developed by CryoMaK for over 30 years. The facility provides a possibility of measuring mechanical, electromechanical and thermal properties of materials and components. Further it is possible to measure tensile force (F), critical magnetic field (Bc) and critical current (Ic) to examine the quench behaviour of superconducting current cables.This article describes new facilities as well as possibilities in relation to testing in CryoMaK.
Treatment of Bio-Oil Refinery Storm Water by a Simulated Constructed Wetland: A Sustainable Management Alternative
Authors: Kraszewska Katherine , Borazjani Hamid , Baldwin Brian , Seale R. Daniel , Jeremic Dragica
Published: January 2016

Contaminated storm-water discharge is a growing concern in the United States owing to a steady increase of harmful pollutants entering freshwater sources. This study remediated contaminated storm-water runoff from a bio-oil conversion facility through a simulated constructed wetland. A six-phase series of constructed wetlands was contaminated with varying dilution levels of bio-oil process water. The study concluded that there was a significant decrease in biological oxygen demand (BOD) and microtoxicity over a 10-day remediation cycle within the constructed wetlands for the lower levels of contaminated storm water. The higher levels of contamination changed very little in total volume of pollution. A comparative screening of the bacterial community within the wetlands during the contamination process showed a similar trend in species richness and composition for the first three phases of contamination. There was a shift in richness and diversity for the final three phases of contamination after 10 days. The constructed wetlands were successful at lowering BOD and toxicity levels and achieving permissible pH levels at dilutions higher than 500 times. When the concentrations of contaminated water were lower than 830 mL of contaminated bio-oil wastewater for every 240 liters of rainwater, the constructed wetlands were successful only at achieving permissible pH discharge levels. Better results for high-level contamination may be achievable with longer residence time in the wetlands.
A Component-based Approach to Modelling Beam Bottom Flange Buckling at Elevated Temperatures
Authors: Quan Guan , Huang Shan-Shan , Burgess Ian
Published: January 2016

In this study, an analytical model of the combination of beam-web shear buckling and bottom-flange buckling at elevated temperatures has been created. This analytical model is able to track the force-deflection path in the post-buckling stage. A range of 3D finite element models has been created using the ABAQUS software. Comparisons have been carried out between the proposed analytical model, finite element modelling and the existing Dharma’s theoretical model. Comparisons indicate that the proposed method is able to provide with accurate predictions for Class 1 and Class 2 beams, and performs better than the existing model, especially for slender beams. A component-based model has been created based on the analytical model, and in due course to be implemented into the software Vulcan for global structural fire analysis.
A Hybrid Model to Predict Localised Cracks of Reinforced Concrete Slabs in Fire
Authors: Liao Feiyu , Huang Zhaohui
Published: January 2016

This paper presents a robust hybrid finite element procedure for predicting the large individual cracks within reinforced concrete floor slabs at elevated temperatures. For modelling the cracks formations and propagations within the floor slabs, the smeared crack model is used for modelling early stages of crack evolution, and then the ‘delayed extended finite element method (D-XFEM) is proposed for capturing individual big cracks within the floor slabs. The new model has been validated against previous fire test results. A series of parametric studies has been conducted on a composite floor to understand the influences of different protection conditions of the support steel beams on both global responses and cracking patterns of the composite floor under fire conditions.
Nonlinear structural analysis of a 2D cut-and-cover tunnel exposed to fire
Authors: Pouran Omid , Harte Reinhard , Peter Carsten
Published: January 2016

Behaviour of cut-and-cover tunnels exposed to fire should be analysed by using a realistic model which takes account ofsimultaneous mechanical and thermal effects acting on the structure.  This has been performed by 2D structural modelsfor a 2-cell tunnel with the aid of FE software package called SOFiSTiK (SOFiSTiK, 2014), in parallel, for two types of elements, beam and plate elements, as a scope of research project financed by BAST. The two considered models were levelled in terms of boundary conditions and the possible mechanical behaviour as well as mesh generation aspects.A nonlinearthermo-mechanical analysis has been performed considering pre-damaged effects on the cross sectionsby taking into account 10 and 15-minute time intervals for a whole duration of 90 minutes. The results of both models are in an acceptable agreement with each other,but they deviate from the simplified, linear-elastic calculation method considering a constant temperature gradient,DTM = 50 K,proposed by ZTV-ING Part 5 (BASt, 2013).To improve this method, a linear interpolation of different DTM-values with respect to the thickness of theconcrete member has been introduced.
STRUCTURAL FIRE SAFETY OF EXISTING STEEL BUILDINGS, Possible general approach and application to the case of the intumescent coatings
Authors: Bilotta Antonio , Silva Donatella De , Nigro Emidio
Published: January 2016

The fire safety of the existing structures is very important from the socio-economic point of view and has high social impact for civil, industrial, and commercial buildings. The verification of the minimum fire resistance of civil structures is done through some regulations, drafted to ensure occupant and rescue teams safety as well as a limited structural damage. These national fire rules are not always easily applicable to existing buildings. The purpose of this paper is to provide guidance about the structural analysis of existing buildings exposed to fire, with particular reference to steel buildings protected with intumescent coatings.
DETERMINING THE FIRE RATING OF CONCRETE STRUCTURES, Case study of using a probabilistic approach and travelling fires
Authors: Kho Tad-Song , Block Florian , Lowry Thomas G.
Published: January 2016

As part of a refurbishment the height of a building in London is to be increased resulting in a change of the fire rating of the existing level from R60 to R90 as per prescriptive guidance. To investigate whether the inherent fire resistance of the structure would be sufficient a state-of-the-art probabilistic approach was adopted, with the approach extended to consider 2D heat-transfer to concrete elements. After determining the required reliability of the structure based on an acceptable risk level, a Monte-Carlo assessment was conducted. This considered for the proposed internal layouts and determined the range of input parameters to be randomly varied in order to define the required range of design fires analysed. The assessment demonstrated that the inherent structural fire resistance would provide sufficient structural reliability for the new use of the building and that no additional fire protection was required to the concrete frame.
INVESTIGATION ACTIVITY ABOUT A COLLAPSED STEEL STRUCTURE SUBJECTED TO A REAL FIRE, Fire scenarios and structural behaviour of a real steel structure
Authors: Prete Iolanda Del , Fiore Nicola Di , Nigro Emidio , Ponticelli Luca , Stefano Giovanni Di
Published: January 2016

The paper describes the behaviour ofa real steel structure collapsed under a fire event. 3D structural analyses were performed with SAFIR program (J-M Franssen, 2005). Different modellingare implemented with some fire load models and analyses of thebehaviour of the whole structure. The main purpose of this work was to investigate the failure types of a warehouse structure under fire conditions. Different fire conditions were applied to the steel frame sections, with ISOcurve (ISO EN 834-8:2002) and zone model approach. The analyses show that with unprotected steel sections, horizontal structures are more critical than columns. Trough applying a performance basedapproach,structure has 30 minutes of fire resistance.
STRUCTURAL FIRE BEHAVIOUR OF Z PURLINS
Authors: Schwarz Ivo , Slatinka Martin , Jandera Michal
Published: January 2016

Cold-formed sections are very common and efficient as secondary load-caring structural members. But the current European design standard EN 1993-1-2 sets the limiting temperature for the Class 4 sections to 350°C which is generallyvery conservative approach.This paper is focused on the thin-walled profilebehaviourin case offire. In particular, the paper describes transition from the beam to fibre behaviour of a Z purlin. A sophisticated shell element FE model is shown and compared to the test. Later, a more practical (Engineering) model neglecting the bending stiffness entirely is made and compared to the previous results. The conclusions show, that such simplified description of real behaviour is possible to be used after the bending capacity of the member is exceeded and predicts the forces to connection well.
EXPERIMENTAL RESEARCH ON T-STUBS UNDER ELEVATED TEMPERATURES
Authors: Both Ioan , Mărginean Ioan , Neagu Calin , Dinu Florea , Dubina Dan , Zaharia Raul
Published: January 2016

Bolted end plate connections are widely used in multi-storey steel frame structures. Their design is based on the component method, which evaluates the behaviour of the basic components through equivalent T-stubs, to model the tension zone that constitutes the most relevant source of deformability. The paper presents the results of an experimental research on bolted T-stubs, tested under elevated temperatures, in normal and high strain rate loading conditions. The influence of the loading rate on the resistance and ductility of the T-stubs subjected to elevated temperatures is emphasized.
EXPERIMENTAL STUDIES OF UNPROTECTED AND PROTECTED STEEL STRUCTURES UNDER FIRE
Authors: Saulnier Véronique , Durif Sébastien , Bouchaïr Abdelhamid , Audebert Philippe , Lahmar Mohamed
Published: January 2016

Preliminary fire experimental tests have been carried out on steel plates protected with intumescent coating.

The tests evaluated and measured the heating of steel plates with various geometrical configurations: shape, size. A first test on an equal leg angle section showed interesting results with different coating expansion on the faces of the section.
The second test campaign is done with different protections to compare behaviors of four steel plates. The first objective is to set up an experimental protocol for future tests. Those results are used to evaluate analytical prevision of steel plate temperature with and without fire protection.
POST-FIRE SAFETY OF CONCRETE COLUMNS, An engineering-oriented reliability-based assessment tool
Authors: Coile Ruben Van , Caspeele Robby , Taerwe Luc
Published: January 2016

Concrete insulation properties and chemo-physical stability up to 400-500°C generally prevents concrete structures from collapsing in fire. Consequently, the safety assessment of reinforced concrete members – and specifically columns – is a must past any severe fire. This post-fire assessment should be based on reliability considerations, as many uncertainties are associated with both the fire evolution and the residual mechanical properties of the materials. The reliability considerations should clarify whether the column has an adequate safety level for its intended post-fire use. An easy-to-use reliability-based assessment method is presented in this paper to determine the bearing capacity of a reinforce concrete column after a fire, and the safety performance of the method is investigated. The proposed method is shown to be at the same time easy to use and very reliable.
A PARAMETRIC STUDY ON BUCKLING OF R/C COLUMNS EXPOSED TO FIRE
Authors: Wang Lijie , Caspeele Robby , Taerwe Luc
Published: January 2016

Buckling of concrete columns is a major issue in fire design, since heating of the columns will result in loss of stiffness and strength in the outer concrete layers. In the Dutch concrete code NEN 6720 (NEN, 1995), a quasi-linear theory of elasticity (KLE) method is provided for columns at ambient temperature. However, no literature is available showing whether this method could be adopted for elevated temperatures. Hence, an efficient calculation tool is needed to validate the applicability of this method in case of fire. As a first step, a cross-sectional calculation tool is introduced to calculate interaction curves of columns at ambient temperature. Further, the interaction diagrams obtained with this numerical method as well as the stiffness method provided in (Eurocode, 2004) and the KLE method are compared. Then, an assumed formula in the KLE-method for the nominal stiffness calculation is discussed considering interaction curves of columns in case of an ISO 834 fire. Finally, parameters like the fire duration and the slenderness ratio are investigated.