A preliminary comparison of the corrosion behaviour of additively and conventionally manufactured 18Ni300 maraging steel for moulds

ABSTRACT: The corrosion behaviour of a maraging steel 18Ni300 manufactured by Laser Powder Bed Fusion (L-PBF) was compared to that of a conventional tool steel. Electrochemical test conditions were chosen to approximate the corrosive environments encountered during injection moulding of polyvinyl chloride (PVC) parts. The corrosion behaviour of the steel produced by both routes was evaluated before and after an ageing treatment at 510 ºC for six hours. Cuboid specimens were fabricated and a polished area of 100 mm2 was immersed in a 0.1M HCl solution for 7 days. Open circuit potential (OCP) and polarization curves were used to monitor the material exposed to the corrosive environment. The obtained results indicate that the conventionally produced aged steel is less susceptible to corrosion and that the steel manufactured by L-PBF (not aged condition) showed better resistance to pitting.info:eu-repo/semantics/publishedVersio

Teoria e prática: a interdisciplinaridade a partir de uma análise investigativa no lançamento de dardo

Neste relato, apresentamos uma tarefa investigativa de análise da trajetória percorrida por um dardo ao ser lançado numa atividade prática da modalidade de atletismo realizado no Instituto Federal do Espírito Santo no ano de 2016. O trabalho teve como objetivo promover a interdisciplinaridade dos componentes curriculares de Matemática e de Educação Física. Participaram 100 alunos de 03 turmas de 2º ano de dois cursos técnicos (Química e Mecânica) integrado ao ensino médio. Sob a ótica de experimento de ensino, adotou-se a metodologia do professor pesquisador, delineada em quatorze encontros, divididas em oito etapas dirigidas por roteiro. Recorreu-se a análise de dados produzidos pelos alunos nos registros individuais, nas entrevistas e nos recursos audiovisuais. Apoiado na metodologia construcionista, os estudantes puderam inferir sobre suas respostas e constatar que, após o lançamento, havia um ângulo ideal de partida e que a trajetória do dardo deveria ser parabólica com curva passível de ser modelada via Geogebra

Electrochemical behavior during the zirconium conversion coating formation on AISI 1006 steel

This study investigated a conversion coating based on hexafluorozirconic acid solution on cold-rolled (AISI 1006) steel sheets, in situ, at different pH values and immersion times. Electrochemical characterization was carried out by electrochemical impedance spectroscopy (EIS) with hexafluorozirconic acid bath as the electrolyte. Laser scanning confocal microscopy (LSCM) was used to evaluate the morphology of the coating in situ, i.e., during the coating formation. According to the results, the polarization resistance (Rp) of the conversion coating is affected by the immersion time and by the pH of the conversion bath. The electrochemical analyzes point out conversion baths at pH between 3.5 and 4.5 and immersion times from 600 to 900 s as optimal operating conditions, achieving an average polarization resistance of 713 ± 107 Ω cm2

P53 and cancer-associated sialylated glygans are surrogate markers of cancerization of the bladder associated with \u3ci\u3eSchistosoma haematobium\u3c/i\u3e infection

Background Bladder cancer is a significant health problem in rural areas of Africa and the Middle East where Schistosoma haematobium is prevalent, supporting an association between malignant transformation and infection by this blood fluke. Nevertheless, the molecular mechanisms linking these events are poorly understood. Bladder cancers in infected populations are generally diagnosed at a late stage since there is a lack of non-invasive diagnostic tools, hence enforcing the need for early carcinogenesis markers. Methodology/Principal Findings Forty-three formalin-fixed paraffin-embedded bladder biopsies of S. haematobium-infected patients, consisting of bladder tumours, tumour adjacent mucosa and pre-malignant/malignant urothelial lesions, were screened for bladder cancer biomarkers. These included the oncoprotein p53, the tumour proliferation rate (Ki-67\u3e17%), cell-surface cancer-associated glycan sialyl-Tn (sTn) and sialyl-Lewisa/x (sLea/sLex), involved in immune escape and metastasis. Bladder tumours of non-S. haematobium etiology and normal urothelium were used as controls. S. haematobium-associated benign/pre-malignant lesions present alterations in p53 and sLex that were also found in bladder tumors. Similar results were observed in non-S. haematobium associated tumours, irrespectively of their histological nature, denoting some common molecular pathways. In addition, most benign/pre-malignant lesions also expressed sLea. However, proliferative phenotypes were more prevalent in lesions adjacent to bladder tumors while sLea was characteristic of sole benign/pre-malignant lesions, suggesting it may be a biomarker of early carcionogenesis associated with the parasite. A correlation was observed between the frequency of the biomarkers in the tumor and adjacent mucosa, with the exception of Ki-67. Most S. haematobium eggs embedded in the urothelium were also positive for sLea and sLex. Reinforcing the pathologic nature of the studied biomarkers, none was observed in the healthy urothelium. Conclusion/Significance This preliminary study suggests that p53 and sialylated glycans are surrogate biomarkers of bladder cancerization associated with S. haematobium, highlighting a missing link between infection and cancer development. Eggs of S. haematobium express sLea and sLex antigens in mimicry of human leukocytes glycosylation, which may play a role in the colonization and disease dissemination. These observations may help the early identification of infected patients at a higher risk of developing bladder cancer and guide the future development of non-invasive diagnostic tests

TCT-44 Independent Mitral Valve Restenosis Predictors After Percutaneous Mitral Balloon Valvuloplasty In A Large, Consecutive Cohort Followed For More Than Two Decades

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Peat bogs of the Serra do Espinhaço Meridional - Minas Gerais, Brazil: I - characterization and classification

As turfeiras são ambientes especiais para estudos relacionados com a dinâmica da matéria orgânica, evolução das paisagens, mudanças climáticas e ciclos de poluição atmosférica locais, regionais e globais. Elas contribuem para o sequestro global de carbono, funcionam como reservatórios de água e constituem o ambiente de uma biodiversidade endêmica. A Serra do Espinhaço Meridional (SdEM), Reserva da Biosfera Terrestre, apresenta uma área significativa formada por diferentes tipos de turfeira, que foram descritas em três perfis, situados a 1.250 m (P1), 1.800 m (P2) e 1.350 m (P4) de altitude e classificados respectivamente como Organossolo Háplico Sáprico térrico (P1), Organossolo Háplico Fíbrico típico (P2) e Organossolo Háplico Hêmico típico (P4), de acordo com o Sistema Brasileiro de Classificação de Solos. Os três perfis foram caracterizados morfologicamente e, nas amostras coletadas, foram realizadas análises químicas, físicas e microbiológicas. Verificou-se que a localização, a altitude e a drenagem influenciaram os atributos morfológicos, físicos, químicos e microbiológicos das turfeiras da SdEM. O estádio de decomposição da matéria orgânica é mais avançado com a melhoria da drenagem nas turfeiras. O teor de metais pesados está relacionado com o teor e a composição granulométrica da fração mineral e com a localização das turfeiras. O perfil P1 apresentou os mais elevados teores médios de Ti, Zr e Pb; em P2 foram detectados os teores médios mais elevados de Mn, Zn e Cu; e o teor médio de Fe é mais elevado em P4. A intensidade da atividade microbiológica das turfeiras P2 e P4 relacionou-se com sua drenagem e com o teor de metais pesados de suas camadas.Peat bogs are a special environment for studies related with the dynamics of organic matter, landscape evolution and climatic changes and with local, regional and global cycles of atmospheric pollution. Peat bogs contribute to the global C sequestration, act as water reservoirs and are the habitat of an endemic biodiversity. The Serra do Espinhaço Meridional (Minas Gerais State, Brazil) - SdEM - a terrestrial biosphere reservation area, contains a considerably large area with different types of peat bogs, which were described in three profiles at 1,250, 1,800 and 1,350 m above sea level and classified, respectively, as Organosol Haplic sapric terric (P1), Organosol Haplic fibric typical (P2) and Organosol Haplic Hemic typical (P4), in agreement with the Brazilian System of Soil Classification. The three profiles were characterized morphologically and the samples were chemically, physically and microbiologically analyzed. It was found that the location, altitude and drainage influenced the morphologic, physical, chemical, and biological properties of the peat bogs in SdEM. The decomposition state of organic matter is more advanced when the drainage in the peat bogs is better. The amount of heavy metals is related with the quantity and granulometric composition of the mineral fraction and location of the peat bogs. The highest mean levels of Ti, Zr, Pb were detected in profile P1, highest mean levels of Mn, Zn and Cu in P2, and the highest mean Fe content in P4. The intensity of microbiological activity in the peat bogs P2 and P4 was related with the drainage and heavy-metal content of its layers.(FAPEMIG) Pesquisa do Estado de Minas Gerai

Sb225002 Induces Cell Death And Cell Cycle Arrest In Acute Lymphoblastic Leukemia Cells Through The Activation Of Glipr1

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Acute Lymphoblastic Leukemia (ALL) is the most frequent childhood malignancy. In the effort to find new anti-leukemic agents, we evaluated the small drug SB225002 (N-(2-hydroxy-4-nitrophenyl)-N'-(2-bromophenyl)urea). Although initially described as a selective antagonist of CXCR2, later studies have identified other cellular targets for SB225002, with potential medicinal use in cancer. We found that SB225002 has a significant pro-apoptotic effect against both B-and T-ALL cell lines. Cell cycle analysis demonstrated that treatment with SB225002 induces G2-M cell cycle arrest. Transcriptional profiling revealed that SB225002-mediated apoptosis triggered a transcriptional program typical of tubulin binding agents. Network analysis revealed the activation of genes linked to the JUN and p53 pathways and inhibition of genes linked to the TNF pathway. Early cellular effects activated by SB225002 included the up-regulation of GLIPR1, a p53-target gene shown to have pro-apoptotic activities in prostate and bladder cancer. Silencing of GLIPR1 in B-and T-ALL cell lines resulted in increased resistance to SB225002. Although SB225002 promoted ROS increase in ALL cells, antioxidant N-Acetyl Cysteine pre-treatment only modestly attenuated cell death, implying that the pro-apoptotic effects of SB225002 are not exclusively mediated by ROS. Moreover, GLIPR1 silencing resulted in increased ROS levels both in untreated and SB225002-treated cells. In conclusion, SB225002 induces cell cycle arrest and apoptosis in different B- and T-ALL cell lines. Inhibition of tubulin function with concurrent activation of the p53 pathway, in particular, its downstream target GLIPR1, seems to underlie the anti-leukemic effect of SB225002.108Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)ICGEBFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)ABALFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FAPESP [05/02390-4]CNPq [401122/05, PC051217]FAPESP [06/01158-3, 08/02106-2]CAPES [1102-08-7

An Efficient Strategy for Electroreduction Reactor Outlet Fractioning into Valuable Products

In this work, two industrial dual-step pressure swing adsorption (PSA) processes were designed and simulated to obtain high-purity methane, CO2, and syngas from a gas effluent of a CO2 electroreduction reactor using different design configurations. Among the set of zeolites that was investigated using Monte Carlo and molecular dynamics simulations, NaX and MFI were the ones selected. The dual-PSA process for case study 1 is only capable of achieving a 90.5% methane purity with a 95.2% recovery. As for case study 2, methane is obtained with a 97.5% purity and 95.3% recovery. Both case studies can produce CO2 with high purity and recovery (&gt;97 and 95%, respectively) and syngas with a H2/CO ratio above 4. Although case study 2 allows methane to be used as domestic gas, a much higher value for its energy consumption is observed compared to case study 1 (64.9 vs 29.8 W h molCH4-1).</p

The Combined Deficiency of Immunoproteasome Subunits Affects Both the Magnitude and Quality of Pathogen- and Genetic Vaccination-Induced CD8+ T Cell Responses to the Human Protozoan Parasite Trypanosoma cruzi

The beta1i, beta2i and beta5i immunoproteasome subunits have an important role in defining the repertoire of MHC class I-restricted epitopes. However, the impact of combined deficiency of the three immunoproteasome subunits in the development of protective immunity to intracellular pathogens has not been investigated. Here, we demonstrate that immunoproteasomes play a key role in host resistance and genetic vaccination-induced protection against the human pathogen Trypanosoma cruzi (the causative agent of Chagas disease), immunity to which is dependent on CD8+ T cells and IFN-gamma (the classical immunoproteasome inducer). We observed that infection with T. cruzi triggers the transcription of immunoproteasome genes, both in mice and humans. Importantly, genetically vaccinated or T. cruzi-infected beta1i, beta2i and beta5i triple knockout (TKO) mice presented significantly lower frequencies and numbers of splenic CD8+ effector T cells (CD8+CD44highCD62Llow) specific for the previously characterized immunodominant (VNHRFTLV) H-2Kb-restricted T. cruzi epitope. Not only the quantity, but also the quality of parasite-specific CD8+ T cell responses was altered in TKO mice. Hence, the frequency of double-positive (IFN-gamma+/TNF+) or single-positive (IFN-gamma+) cells specific for the H-2Kb-restricted immunodominant as well as subdominant T. cruzi epitopes were higher in WT mice, whereas TNF single-positive cells prevailed among CD8+ T cells from TKO mice. Contrasting with their WT counterparts, TKO animals were also lethally susceptible to T. cruzi challenge, even after an otherwise protective vaccination with DNA and adenoviral vectors. We conclude that the immunoproteasome subunits are key determinants in host resistance to T. cruzi infection by influencing both the magnitude and quality of CD8+ T cell responses