Damage Evaluation of Reinforced Concrete Columns by Hypervelocity Impact

AbstractTo evaluate local damages of RC columns by the impacts of a high velocity projectile, impact experiments using a gun method were performed for the 1/10 scale RC columns as test specimens. Effects of an amount of main bar and spacing between hoops were examined. Also, scaling effects were evaluated by comparing with the 1/5 and 1/20 scale models, to ensure the effectiveness of the computer simulations. The crater depth and the residual weight of the specimens after the impact were correlated with the kinetic energy of the projectile although an amount of the reinforcement was not affected to the crater depth. The reinforcement by the hoop was effective to suppress the crack propagation to the back surface, but a threshold might exist in the coverage ratio of the hoop. A scaling effect is not observed for the damage of the RC column

EXPERIMENTAL STUDY ON COUPLING BEAMS WITH STEEL DAMPERS IN MID-SPAN - Coupling beam dampers with low yield point steel (Part 1) -

RC shear walls coupled with beams are becoming widely used for high-rise buildings in Japan. Since short-span coupling beams are subjected to large displacement during an earthquake, high ductility and excellent energy absorption performance are required.RC coupling beams with low-yield-point steel damper in the mid-span (coupling beam damper) have been developed and experimentally investigated in this study. Steel dampers in the mid-span are embedded into the RC beams at the both ends, and embedded lengths are ranging from 2 to 3.5 times as long as steel depth.The coupling beam dampers provide the stable hysteretic performance up to 1/20 of drift angle, and equivalent damping coefficients of 20 to 30%. Sufficient amount of shear reinforcement needs to be arranged, so as to transfer shear force from steel damper to RC beams. Shear reinforcements are more effective when arranged in the tip of RC beams.カテゴリー

RESTORING FORCE CHARACTERISTICS OF COUPLING BEAM DAMPERS - Coupling beam dampers with low yield point steel (Part 2) -

RC coupling beams with low-yield-point steel web panel in the mid-span (coupling beam damper) have been developed and applied to actual buildings. Cyclic loading tests had been performed, resulting that the coupling beam dampers provided the stable hysteretic performance and load carrying capacity did not deteriorate up to 1/20 of drift angle.In this paper, finite element analysis has been carried out to evaluate the shear buckling strength of the coupling beam damper. It is verified that the low-yield-point steel web panel (with width-thick ratio of about 15) of the coupling beam damper is thick enough to avoid shear buckling. Restoring force characteristics of the coupling beam dampers for structural design is also proposed. An appropriate modeling of RC parts is important to represent the total structural performance.カテゴリー

Evaluation of photodegradable tape on grafting in citrus nursery trees

O trabalho avaliou os efeitos do uso de fita fotodegradável de enxertia em mudas de laranjeira 'Valência' enxertadas em limoeiro 'Cravo' e citrumeleiro 'Swingle', em viveiro telado, em Bebedouro-SP, durante os meses de setembro a novembro de 2009. Para cada porta-enxerto, foram avaliados três tratamentos, que incluíram o uso da fita convencional de polietileno para a fixação da borbulha e a fita fotodegradável, por sua vez aplicada sob duas formas: com e sem envolvimento completo da gema. As variáveis avaliadas foram: tempo consumido na operação de amarrio da fita, porcentagem de borbulhas brotadas, comprimento e diâmetro do enxerto e porcentagem de mudas prontas para comercialização. O delineamento experimental adotado foi o de blocos ao acaso, com seis tratamentos e quatro repetições. Cada parcela foi representada por 12 plantas. Os tratamentos com a fita fotodegradável, com e sem envolvimento da gema, anteciparam a brotação do enxerto, apesar de o tempo gasto no amarrio da fita ser significativamente maior em relação ao método convencional. Quando o porta-enxerto utilizado é o citrumeleiro Swingle, menos vigoroso, recomenda-se manter a gema descoberta para evitar redução acentuada da brotação do enxerto

Autophagy requires endoplasmic reticulum targeting of the PI3-kinase complex via Atg14L

Generation of PI3P in the normally PI3P-deficient ER membrane makes the organelle a platform for autophagosome formation

Innate Immune Sensing of Modified Vaccinia Virus Ankara (MVA) Is Mediated by TLR2-TLR6, MDA-5 and the NALP3 Inflammasome

Modified vaccinia virus Ankara (MVA) is an attenuated double-stranded DNA poxvirus currently developed as a vaccine vector against HIV/AIDS. Profiling of the innate immune responses induced by MVA is essential for the design of vaccine vectors and for anticipating potential adverse interactions between naturally acquired and vaccine-induced immune responses. Here we report on innate immune sensing of MVA and cytokine responses in human THP-1 cells, primary human macrophages and mouse bone marrow-derived macrophages (BMDMs). The innate immune responses elicited by MVA in human macrophages were characterized by a robust chemokine production and a fairly weak pro-inflammatory cytokine response. Analyses of the cytokine production profile of macrophages isolated from knockout mice deficient in Toll-like receptors (TLRs) or in the adapter molecules MyD88 and TRIF revealed a critical role for TLR2, TLR6 and MyD88 in the production of IFNβ-independent chemokines. MVA induced a marked up-regulation of the expression of RIG-I like receptors (RLR) and the IPS-1 adapter (also known as Cardif, MAVS or VISA). Reduced expression of RIG-I, MDA-5 and IPS-1 by shRNAs indicated that sensing of MVA by RLR and production of IFNβ and IFNβ-dependent chemokines was controlled by the MDA-5 and IPS-1 pathway in the macrophage. Crosstalk between TLR2-MyD88 and the NALP3 inflammasome was essential for expression and processing of IL-1β. Transcription of the Il1b gene was markedly impaired in TLR2−/− and MyD88−/− BMDM, whereas mature and secreted IL-1β was massively reduced in NALP3−/− BMDMs or in human THP-1 macrophages with reduced expression of NALP3, ASC or caspase-1 by shRNAs. Innate immune sensing of MVA and production of chemokines, IFNβ and IL-1β by macrophages is mediated by the TLR2-TLR6-MyD88, MDA-5-IPS-1 and NALP3 inflammasome pathways. Delineation of the host response induced by MVA is critical for improving our understanding of poxvirus antiviral escape mechanisms and for designing new MVA vaccine vectors with improved immunogenicity