153 research outputs found

    Process and machine system development for the forming of miniature/micro sheet metal products

    Get PDF
    This paper reports on the current development of the process for the forming of thin sheet-metal micro-parts (t < 50µm) and the corresponding machine system which is part of the research and technological development of an EU funded integrated project - MASMICRO ("Integration of Manufacturing Systems for the Mass-Manufacture of Miniature/Micro-Products" (/www.masmicro.net/). The process development started with qualification of the fundamentals related to the forming of thin sheet-metals in industrial environment, for which a testing machine and several sets of the testing tools were developed. The process was further optimised, followed by new tool designs. Based on the experience gained during the process development, a new forming press which is suitable for industrial, mass-customised production, has been designed

    Development of a new machine system for the forming of micro-sheet-products

    Get PDF
    Most of the developed micro-forming machines were based on standalone concepts which do not support efficient integration to make them fully automated and integrated. At present, material feeding in micro-forming is not of sufficient precision and reliability for high throughput manufacturing applications. Precise feeding is necessary to ensure that micro-parts can be produced with sufficient accuracy, especially in multi-stage forming, while high-speed feeding is a must to meet the production-rate requirements. Therefore, design of a new high-precision and high-speed feeder for micro-forming is proposed. Several possible approaches are examined with a view to establishing feasible concepts. Based on the investigation, several concepts for thin sheet-metal feeding for micro-forming are generated, they being argued and assessed with applicable loads and forces analysis. These form a basis of designing a new feeder

    Viagem à Índia para prospecção de tecnologias sobre mamona e pinhão manso.

    Get PDF
    Viagem á Índia para prospecção de tecnologias sobre mamona e pinhão manso ; Introdução; Roteiro; Detalhamento; Sardar Krushinagar Dantiwada University; Pesquisas com mamona; Pesquisas com pinhão manso; Outras oleaginosas ; Indústria de extração de óleo de mamona ; Mercado de leilões para comercialização de produtos agrícolas ; Mini-usina de biodiesel de pinhão manso; 4º Seminário Internacional sobre semente e óleo de mamona e produtos de valor agregado ; Visita à Secretaria de Agricultura do Estado de Tamil Nadu ; Projeto MGR jatropha biodiesel ; Loco Works - Empresa operadora de ferrovias ; Exposição sobre a mini-usina de biodiesel da Empresa Loco Works ; Considerações finais; Pinhão manso ; Mamona.bitstream/CNPA/18319/1/DOC153.pd

    Proprotein convertases blockage up-regulates specifically metallothioneins coding genes in human colon cancer stem cells

    Get PDF
    ABSTRACT: Despite continuous exertion made, colon cancer still represents a major health problem and its incidence continues being high worldwide. There is growing evidence in support of the cancer stem cells (CSCs) being central in the initiation of this cancer, and CSCs have been the focus of various studies for the identification of new ways of treatment. Lately, the proprotein convertases (PCs) were reported to regulate the maturation and expression of various molecules involved in the malignant phenotype of colon cancer cells, however, the identity of the molecules regulated by these serine proteases in CSCs is unknown. In this study, we used the general PCs inhibitor, the Decanoyl-RVKR-chloromethylketone (Decanoyl-RVKR-CMK) that inhibits all the PCs found in the secretory pathway, and analyzed its effect on CSCs using RNA-seq analysis. Remarkably, from the only 9 upregulated genes in the human SW620-derived sphere-forming cells, we identified 7 of the 11 human metallothioneins, all of them localized on chromosome 16, and zinc related proteins as downstream effectors of the PCs. The importance of these molecules in the regulation of cell proliferation, differentiation and chemoresistance, and their reported potential tumor suppressor role and loss in colon cancer patients associated with worse prognosis, suggests that targeting PCs in the control of the malignant phenotype of CSCs is a new potential therapeutic strategy in colon cancer

    Intermediate Vancomycin Susceptibility in a Community-associated MRSA Clone

    Get PDF
    We describe a case of treatment failure caused by a strain of USA300 community-associated methicillin-resistant Staphylococcus aureus (MRSA) with intermediate susceptibility to vancomycin and reduced susceptibility to daptomycin. The strain was isolated from the bone of a 56-year-old man with lumbar osteomyelitis after a 6-week treatment course of vancomycin for catheter-associated septic thrombophlebitis

    Vacuum decay in quantum field theory

    Get PDF
    We study the contribution to vacuum decay in field theory due to the interaction between the long and short-wavelength modes of the field. The field model considered consists of a scalar field of mass MM with a cubic term in the potential. The dynamics of the long-wavelength modes becomes diffusive in this interaction. The diffusive behaviour is described by the reduced Wigner function that characterizes the state of the long-wavelength modes. This function is obtained from the whole Wigner function by integration of the degrees of freedom of the short-wavelength modes. The dynamical equation for the reduced Wigner function becomes a kind of Fokker-Planck equation which is solved with suitable boundary conditions enforcing an initial metastable vacuum state trapped in the potential well. As a result a finite activation rate is found, even at zero temperature, for the formation of true vacuum bubbles of size M1M^{-1}. This effect makes a substantial contribution to the total decay rate.Comment: 27 pages, RevTeX, 1 figure (uses epsf.sty

    Vacuum decay in quantum field theory

    Get PDF
    We study the contribution to vacuum decay in field theory due to the interaction between the long and short-wavelength modes of the field. The field model considered consists of a scalar field of mass MM with a cubic term in the potential. The dynamics of the long-wavelength modes becomes diffusive in this interaction. The diffusive behaviour is described by the reduced Wigner function that characterizes the state of the long-wavelength modes. This function is obtained from the whole Wigner function by integration of the degrees of freedom of the short-wavelength modes. The dynamical equation for the reduced Wigner function becomes a kind of Fokker-Planck equation which is solved with suitable boundary conditions enforcing an initial metastable vacuum state trapped in the potential well. As a result a finite activation rate is found, even at zero temperature, for the formation of true vacuum bubbles of size M1M^{-1}. This effect makes a substantial contribution to the total decay rate.Comment: 27 pages, RevTeX, 1 figure (uses epsf.sty
    corecore