Nano-surface layers were prepared on the surface of 6061 aluminum alloy using the ultrasonic surface rolling process (USRP). The surface morphology, surface roughness, microstructure, hardness, and corrosion resistance of 6061 aluminum alloy were systematically characterized using X-ray diffraction (XRD), laser scanning confocal microscopy (LSCM), optical microscope(OM), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and other testing methods. The results showed that ultrasonic surface rolling strengthening did not change the surface phase composition of 6061 aluminum alloy. It changed the size of the surface phases and the distance between the phases while refining the surface grains. The static pressures has a great influence on the surface properties of 6061 aluminum alloy. The best surface properties were obtained under 500N static pressures. The surface hardness reached 129.5HV0.5, the surface morphology was flat and continuous, the surface roughness was reduced to Ra0.191μm, and the corrosion resistance was significantly improved.

RESUMO O uso de engenharia assistida por computador (CAE) na fase de projeto do conceito do automóvel tornou-se um ponto de acesso na pesquisa de fatores humanos. Com base no software computacional biomecânico musculoesquelético humano, foi construído um modelo musculoesquelético sentado para descrever a postura sentada natural de um condutor. A interação entre um motorista e um carro em várias combinações de ângulos de inclinação do assento-pan/encosto foi analisada usando uma abordagem dinâmica do verso. A fim de descobrir a postura de condução “mais confortável” do assento-pan/encosto, o efeito dos ângulos de inclinação do assento-pan/dorso sobre o grau de atividade muscular e a força de compressão intradiscal L4-L5 foi investigado. Os resultados mostraram que um ângulo de inclinação para trás muito maior, aproximadamente 15°, e um ligeiro assento-pan para trás, cerca de 7°, pode aliviar a fadiga muscular e levar a dirigir em uma posição confortável. Posteriormente, de acordo com as conclusões acima expostas, foi construída uma função preliminar de conforto ao dirigir.

SUMMARY Using computer-aided engineering (CAE) in the concept design stage of automobiles has become a hotspot in human factor engineering research. Based on human musculoskeletal biomechanical computational software, a seated human-body musculoskeletal model was built to describe the natural sitting posture of a driver. The interaction between the driver and car in various combinations of seat-pan/back-rest inclination angles was analyzed using an inverse-dynamics approach. In order to find out the “most comfortable” driving posture of the seat-pan/back-rest, the effect of seat-pan/back-rest inclination angles on the muscle activity degree, and the intradiscal L4-L5 compression force were investigated. The results showed that a much larger back-rest inclination angle, approximately 15°, and a slight backward seat-pan, about 7°, may relieve muscle fatigue and provide more comfort while driving. Subsequently, according to the findings above, a preliminary driving-comfort function was constructed.

Systemic lupus erythematosus (SLE) is an autoimmune disease associated with an aberrant activation of immune cells partly due to the dysfunction of cytokines such as type I interferons (IFNs). Long non-coding RNA MALAT1 has been found to play a pathogenic role in SLE; however, the underlying mechanisms are still poorly understood. Bioinformatics analysis showed the up-regulation of type I IFN downstream effectors OAS2, OAS3, and OASL (OAS-like) in CD4+ T cells, CD19+ B cells, and CD33+ myeloid cells in patients with active SLE compared to healthy participants. In this study, peripheral blood mononuclear cells (PBMCs), CD19+ B, and CD4+ T cells were isolated from active SLE patients and healthy participants. PCR was performed to quantify MALAT1, OAS2, OAS3, and OASL expression in immune cells. MALAT1, OAS2, OAS3, and OASL were knocked down in CD4+ T cells to investigate the regulatory effect of MALAT1 on the effectors and their involvement in type I IFNs-mediated inflammation. Results showed higher OAS2, OAS3, and OASL expression in active SLE patients. MALAT1 expression was positively correlated to OAS2, OAS3, and OASL expression in CD19+ B or CD4+ T cells. MALAT1 knockdown decreased OAS2, OAS3, and OASL expression. Treatment with IFN-α-2a increased the expression of TNF-α, IL-1β, and IFN-α in CD4+ T cells. However, knockdown of MALAT1, OAS2, OAS3, and OASL alone inhibited the effect of IFN-α-2a on TNF-α and IL-1β. This study suggested the involvement of MALAT1 in type I IFNs-mediated SLE by up-regulating OAS2, OAS3, and OASL.

RESUMO OBJETIVO: Realizamos este estudo para definir e medir a inclinação radial dorsal, e para orientar a redução das fraturas do raio distal e a pré-flexão das chapas de aço utilizadas na cirurgia. MÉTODOS: A inclinação radial dorsal foi medida usando tomografia computadorizada (TC) e raios X dos lados esquerdo e direito. As diferenças e correlações dos dados medidos por esses dois métodos e de dois lados foram analisadas. RESULTADOS: As inclinações medidas por raios X foram significativamente maiores que as medidas pela TC do lado esquerdo (t=55,51, p<0,01) e do lado direito (t=49,81, p<0,01). As inclinações medidas por esses dois métodos dos lados esquerdo e direito foram correlacionadas (r=0,85, p<0,01; r=0,81, p<0,01). As inclinações radiais dorsais medidas a partir do lado esquerdo não foram significativamente diferentes das medidas do lado direito por CT (t=1,49, p>0,05) e por raios X (t=1,51, p>0,05). As inclinações radiais dorsais medidas a partir do lado esquerdo por TC foram significativamente diferentes das medidas a partir do lado direito por raios X (t=43,07, p<0,01), e esses dois conjuntos de dados foram correlacionados (r=0,71, p<0,01). As inclinações radiais dorsais medidas a partir do lado esquerdo por raios X foram significativamente diferentes das medidas do lado direito por CT (t=40,43, p<0,01), e esses dois conjuntos de dados também foram correlacionados (r=0,75, p<0,01). CONCLUSÕES: As inclinações radiais dorsais medidas de um lado por um método podem ser usadas para estimar as inclinações medidas do outro lado/o mesmo lado pelo mesmo método/o outro método.

SUMMARY OBJECTIVE: We conducted this study to define and measure the dorsal radial tilt, and to guide the reduction of distal radius fractures and the pre-bending of steel plates used in surgery. METHODS: The dorsal radial tilt was measured using both computed tomography (CT) and x-ray from both left and right side. The differences and correlations of the data measured by those two methods and from two sides were analyzed. RESULTS: The tilts measured by x-ray were significantly bigger than those measured by CT from the left side (t=55.51, p < 0.01) and from the right side (t=49.81, p < 0.01). The tilts measured by those two methods from the left and right sides were correlated (r=0.85, p < 0.01; r=0.81, p < 0.01). The dorsal radial tilts measured from the left side were not significantly different from those measured from the right side by CT (t=1.49, p > 0.05) and by x-ray (t=1.51, p > 0.05). The dorsal radial tilts measured from the left side by CT were significantly different from those measured from the right side by x-ray (t=43.07, p < 0.01), and these two sets of data were correlated (r=0.71, p < 0.01). The dorsal radial tilts measured from the left side by x-ray was significantly different from that measured from right side by CT (t=40.43, p < 0.01), and those two sets of data were also correlated (r=0.75, p < 0.01). Conclusions: The dorsal radial tilts measured from one side by one method can be used to estimate the tilts measured from the other side / the same side by the same method / the other method.

Recentemente, a criptografia de chave pública sem certificado (CLPKC) tem sido amplamente estudada, uma vez que poderia resolver o problema de gerenciamento de certificados na criptografia de chave pública tradicional (TPKC) e o problema chave de escrow da criptografia de chave pública baseada em identidade (ID-based PKC). Para atender aos requisitos de diferentes aplicações, têm sido propostos muitos sistemas de assinatura cega sem certificado (CLBs), sistemas que utilizam o emparelhamento bilinear para a configuração de CLPKC. No entanto, a operação de emparelhamento bilinear é muito complicada. Portanto, o desempenho desses regimes CLBs não é muito satisfatório. Para resolver o problema, propomos um esquema de CLBS eficiente sem emparelhamento bilinear. Uma análise de desempenho mostra que o esquema proposto poderia reduzir os custos de computação e armazenamento. Uma análise de segurança mostra que o esquema proposto é comprovadamente seguro contra dois tipos de adversários.

Recently, the certificateless public key cryptography (CLPKC) has been studied widely since it could solve both of the certificate management problem in traditional public key cryptography (TPKC) and the key escrow problem in the identity-based public key cryptography (ID-based PKC). To satisfy requirements of different applications, many certificateless blind signature (CLBS) schemes using bilinear pairing for the CLPKC setting have been proposed. However, the bilinear pairing operation is very complicated. Therefore, the performance of those CLBS schemes is not very satisfactory. To solve the problem, we propose an efficient CLBS scheme without bilinear pairing. Performance analysis shows that the proposed scheme could reduce costs of computation and storage. Security analysis shows the proposed scheme is provably secure against both of two types of adversaries.