Development of a simple closed-loop type algorithm for determination of variable blank holder force trajectory and its applications to square cup deep drawing

金沢大学理工研究域機械工学系In deep drawing, a low blank holder force (BHF) can cause wrinkling, while a high BHF can lead to tearing. In this study, a variable blank holder force (VBHF) approach to deep drawing is employed, and a simple closed-loop type algorithm is developed for the VBHF trajectory. The proposed algorithm is divided into two phases. The objective of the first phase is to check wrinkling and tearing. In this phase, a low BHF is used as the initial BHF, which is then increased to prevent wrinkling while controlling tearing. This phase of the algorithm is terminated when tearing occurs. In numerical simulation, the distance between the die and the blank holder is used to measure wrinkling, and the minimum thickness of the blank is used to determine the tearing. In the second phase of the algorithm, the deviations in thickness of the part are iteratively examined, without neglecting the occurrence of wrinkling. One of the advantages of using VBHF instead of constant BHF is that it reduces the forming energy. The validity of the proposed algorithm is examined comparing numerical simulation and experimental results. Finally, the proposed algorithm is also applied to obtain the segmented VBHF trajectory. © 2010 Satoshi Kitayama et al

Size dependent nanomechanics of coil spring shaped polymer nanowires

Direct laser writing (DLW) via two-photon polymerization (TPP) has been established as a powerful technique for fabrication and integration of nanoscale components, as it enables the production of three dimensional (3D) micro/nano objects. This technique has indeed led to numerous applications, including micro- and nanoelectromechanical systems (MEMS/NEMS), metamaterials, mechanical metamaterials, and photonic crystals. However, as the feature sizes decrease, an urgent demand has emerged to uncover the mechanics of nanosized polymer materials. Here, we fabricate coil spring shaped polymer nanowires using DLW via two-photon polymerization. We find that even the nanocoil springs follow a linear-response against applied forces, following Hooke’s law, as revealed by compression tests using an atomic force microscope. Further, the elasticity of the polymer material is found to become significantly greater as the wire radius is decreased from 550 to 350 nm. Polarized Raman spectroscopy measurements show that polymer chains are aligned in nanowires along the axis, which may be responsible for the size dependence. Our findings provide insight into the nanomechanics of polymer materials fabricated by DLW, which leads to further applications based on nanosized polymer materials

Star Formation Activity Beyond the Outer Arm II: Distribution and Properties of Star Formation

The outer Galaxy beyond the Outer Arm represents a promising opportunity to study star formation in an environment vastly different from the solar neighborhood. In our previous study, we identified 788 candidate star-forming regions in the outer Galaxy (at galactocentric radii $R_{\rm G}$ $\ge$ 13.5 kpc) based on Wide-field Infrared Survey Explorer (WISE) mid-infrared (MIR) all-sky survey. In this paper, we investigate the statistical properties of the candidates and their parental molecular clouds derived from the Five College Radio Astronomy Observatory (FCRAO) CO survey. We show that the molecular clouds with candidates have a shallower slope of cloud mass function, a larger fraction of clouds bound by self-gravity, and a larger density than the molecular clouds without candidates. To investigate the star formation efficiency (SFE) at different $R_{\rm G}$, we used two parameters: 1) the fraction of molecular clouds with candidates and 2) the monochromatic MIR luminosities of candidates per parental molecular cloud mass. We did not find any clear correlation between SFE parameters and $R_{\rm G}$ at $R_{\rm G}$ of 13.5 kpc to 20.0 kpc, suggesting that the SFE is independent of environmental parameters such as metallicity and gas surface density, which vary considerably with $R_{\rm G}$. Previous studies reported that the SFE per year (SFE/yr) derived from the star-formation rate surface density per total gas surface density, HI plus H$_2$, decreases with increased $R_{\rm G}$. Our results might suggest that the decreasing trend is due to a decrease in HI gas conversion to H$_2$ gas.Comment: 40 pages, 26 figures, 5 tables, accepted for publication in Ap

A closed-loop type algorithm for determination of variable blank holder force trajectory and its application to square cup deep drawing

金沢大学理工研究域機械工学系In deep drawing, a low blank holder force (BHF) can cause wrinkling, while a high BHF can lead to tearing. Thus, it is important to determine the appropriate BHF to be utilized in the forming process. In this study, a variable blank holder force (VBHF) approach to deep drawing is employed, and a simple closed-loop type algorithm is developed to obtain the VBHF trajectory. The proposed algorithm is divided into two phases. The objective of the first phase is to check wrinkling and tearing. In this phase, a low BHF, which is the cause of wrinkling, is used as the initial BHF; it is then increased to prevent wrinkling. The algorithm is terminated when tearing occurs. In a numerical simulation, the distance between the die and the blank holder is used to measure wrinkling. On the other hand, the thickness of the blank is used to determine the tearing. Next, in the second phase, the deviations in thickness are examined. Wrinkles are also checked in the second phase. By iterating the above two phases, the VBHF trajectory can be obtained. One of the advantages of the VBHF is that it reduces the forming energy. The validity of the proposed algorithm is examined through both a numerical simulation and experiment. © 2010 Springer-Verlag London Limited

Mediators between canagliflozin and renoprotection vary depending on patient characteristics: Insights from the CREDENCE trial

Aim: To identify the mediators between canagliflozin and renoprotection in patients with type 2 diabetes at a high risk of end-stage kidney disease (ESKD). Methods: In this post hoc analysis of the CREDENCE trial, the effect of canagliflozin on potential mediators (42 biomarkers) at 52 weeks and the association between changes in mediators and renal outcomes were evaluated using mixed-effects and Cox models, respectively. The renal outcome was a composite of ESKD, serum creatinine doubling or renal death. The percentage of the mediating effect of each significant mediator was calculated based on changes in the hazard ratios of canagliflozin after additional adjustment of the mediator. Results: Changes in haematocrit, haemoglobin, red blood cell (RBC) count and urinary albumin-to-creatinine ratio (UACR) at 52 weeks significantly mediated 47%, 41%, 40% and 29% risk reduction with canagliflozin, respectively. Further, 85% mediation was attributed to the combined effect of haematocrit and UACR. A large variation in mediating effects by haematocrit change existed among the subgroups, ranging from 17% in those patients with a UACR of more than 3000 mg/g to 63% in patients with a UACR of 3000 mg/g or less. In the subgroups with a UACR of more than 3000 mg/g, UACR change was the highest mediating factor (37%), driven by the strong association between UACR decline and renal risk reduction. Conclusions: The renoprotective effects of canagliflozin in patients at a high risk of ESKD can be significantly explained by changes in RBC variables and UACR. The complementary mediating effects of RBC variables and UACR may support the renoprotective effect of canagliflozin in different patient groups.Doi Y., Hamano T., Yamaguchi S., et al. Mediators between canagliflozin and renoprotection vary depending on patient characteristics: Insights from the CREDENCE trial. Diabetes, Obesity and Metabolism , (2023); https://doi.org/10.1111/dom.15191

Radiologic Findings of IgG4-Related Disease

Autoimmune pancreatitis (AIP), characterized by an autoimmune phenomenon of prominent lymphocytes, IgG4-bearing plasma cell infiltration and storiform fibrosis, has been widely reported as a specific type of chronic pancreatitis. Typical image findings of this disease are reported as diffuse pancreatic swelling and a capsule-like rim on CT or MRI. However, AIP presents with a variable morphology, such as focal, segmental and multifocal swellings. Because imaging findings for AIP can look like those of pancreatic cancer, AIP has often been treated with unnecessary surgical resection. In addition, AIP is complicated by the involvement of various other organs besides the pancreas that show lymphoplasmacytic infiltration and fibrosis. These are frequently misdiagnosed as inherent lesions of corresponding organs. Furthermore, these extra-pancreatic lesions show systemic distribution and share common features of IgG4- bearing plasma cell infiltration as well as favorable responses to corticosteroid, indicating the presence of systemic condition, IgG4-related diseases. AIP is now recognized as an IgG4-related disease. Detailed evaluations of imaging findings of CT, MRI and Gallium-67 (Ga-67) scintigraphy for the involvement of these various organs are useful for a correct diagnosis of this systemic disease.ArticleCurrent Immunology Reviews. 7(2):186-203 (2011)journal articl