265 research outputs found

    Finite-Width Bundle is Most Stable in a Solution with Salt

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    We applied the mean-field approach to a columnar bundle assembled by the parallel arrangement of stiff polyelectrolyte rods in a salt bath. The electrostatic potential can be divided into two regions: inside the bundle for condensed counter-ions, and outside the bundle for free small ions. To determine the distribution of condensed counter-ions inside the bundle, we use a local self-consistent condition that depends on the charge density, the electrostatic potential, and the net polarization. The results showed that, upon bundle formation, the electric charge of polyelectrolytes, even those inside the bundle, tend to survive in an inhomogeneous manner, and thus their width remains finite under thermal equilibrium because of the long-range effect of charge instability.Comment: 7 pages, 4 figure

    Non-Equilibrium Ionization State and Two-Temperature Structure in the Linked Region of Abell 399/401

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    We investigate a non-equilibrium ionization state and two-temperature structure of the intracluster medium in the linked region of Abell 399/401, using a series of N-body + SPH simulations, and find that there exist significant shock layers at the edge of the linked region, and that the ionization state of iron departs from the ionization equilibrium state at the shock layers and around the center of the linked region. As for the two-temperature structure, an obvious difference of temperature between electrons and ions is found in the edge of the linked regions. K alpha line emissions of Fe xxiv and Fe xxv are not severely affected by the deviation from the ionization equilibrium state around the center of the linked region, suggesting that the detection of relatively high metallicity in this area cannot be ascribed to the non-equilibrium ionization state of the intracluster medium. On the other hand, the K alpha emissions are significantly deviated from the equilibrium values at the shock layers, and the intensity ratio of K alpha lines between Fe xxiv-xxv and Fe xxvi is found to be significantly altered from that in the ionization equilibrium state.Comment: 4 pages, 2 figures, submitted to PASJ Letter; accepted June

    How are small ions involved in the compaction of DNA molecules?

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    DNA is a genetic material found in all life on Earth. DNA is composed of four types of nucleotide subunits, and forms a double-helical one-dimensional polyelectrolyte chain. If we focus on the microscopic molecular structure, DNA is a rigid rod-like molecule. On the other hand, with coarse graining, a long-chain DNA exhibits fluctuating behavior over the whole molecule due to thermal fluctuation. Owe to its semiflexible nature, individual giant DNA molecule undergoes a large discrete transition in the higher-order structure. In this folding transition into a compact state, small ions in the solution have a critical effect, since DNA is highly charged. In the present article, we interpret the characteristic features of DNA compaction while paying special attention to the role of small ions, in relation to a variety of single-chain morphologies generated as a result of compaction

    Brain Waves as Unconscious Biometrics towards Continuous Authentication : The Effects of Introducing PCA into Feature Extraction

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    For user management in high-security systems, continuous authentication is required, where unconscious biometrics is suitable. We have proposed to use brain waves as such unconscious biometrics. Assuming continuous authentication of drivers, we have measured brain waves in virtual driving environments and evaluated the verification performance. In this paper, we introduce Principle Component Analysis (PCA) into the feature extraction. It is confirmed that the introduction of PCA is effective for improving the verification performance

    Sidedness of CRC on tumor immunity

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    Background Clinical and molecular characteristics differ between right-sided and left-sided colorectal cancer (CRC). This study aimed to clarify the correlation between CRC sidedness and tumor immunity. Methods A total of 102 patients who underwent curative colectomy for stage II/III CRC were included in this study. The expression of programmed cell death (PD)-1, PD1-ligand 1 (PD-L1), forkhead box P3 (Foxp3), transforming growth factor (TGF)-β, and indoleamine-pyrrole 2,3-dioxygenase (IDO) were examined using immunohistochemistry and the relationships between sidedness and several prognostic factors were examined. Results Clinicopathological factors were not significantly different between right- and left-sided CRC. The tumor immunity-related molecule PD-L1 was more highly expressed in right-sided than in left-sided CRC (62.9% vs. 30.6%, p<0.01). No significant difference was found in overall survival (OS) and disease-free survival (DFS) by sidedness. PD-1 and Foxp3 expression were significant prognostic factors for OS. Lymph node metastasis (N), lymphatic invasion (ly), and PD-L1 expression were significant prognostic factors for DFS. In right-sided CRC, IDO-positive patients had a poor OS (p<0.05), and IDO was the only independent prognostic indicator for OS. N and venous invasion were identified as independent prognostic indicators for DFS. In left-sided CRC, univariate analysis identified PD-1, PD-L1, and Foxp3 expression as significant predictors of poor OS. Multivariate analysis confirmed PD-L1 expression as an independent prognostic indicator. N, ly, and PD-L1 expression levels were identified as significant predictors of poor DFS. Conclusions The prognostic factors were IDO in right-sided CRC and PD-L1 and Foxp3 in left-sided CRC. These findings indicated that tumor immunity might play different roles depending upon sidedness. Tumor location may be an important factor to consider when assessing immune response and therapeutic decisions in CRC patients

    Pre-operative weight loss program

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    Background : The aim of this study was to investigate the influence of obesity and the usefulness of a pre-operative weight loss program (PWLP) for obese patients undergoing laparoscopic gastrectomy (LG) for gastric cancer (GC). Materials and Methods : Study1 : 219 patients who underwent laparoscopic distal gastrectomy (LDG) for GC were divided into 2 groups : body mass index (BMI) ≧ 28 and BMI < 28kg / m2. The influence of BMI in LG surgery was investigated. Study2 : The BMI ≧ 28 kg / m2 patients with a planned LG (n = 8) undertook a PWLP including calorie restriction and exercise. The effects of this program were evaluated. Results : Study1 : The BMI ≧ 28kg / m2 group showed significantly longer operation times, more blood loss and a higher frequency of post-operative complications than that of the BMI < 28kg / m2 group. Study 2 : The patients achieved a weight loss of 4.2%. The visceral fat area (VFA) was significantly decreased by 10.6%, whereas skeletal muscle mass was unaffected. The PWLP group showed shorter operation times, less blood loss and a lower frequency of post-operative complications compared with that of the BMI ≧ 28kg / m2 group. Conclusion : Obesity is an important risk factor and a pre-operative weight loss program is useful for obese patients undergoing a LG

    The influence and countermeasure of obesity in laparoscopic colorectal resection

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    Background: The aim of this study was to investigate the influence of obesity and the usefulness of a preoperative weight loss program (PWLP) for obese patients undergoing laparoscopic colorectal resection (LCR). Methods: Study 1: 392 patients who underwent LCR for colorectal cancer were divided into two groups: those with a body mass index (BMI) ≥25 kg/m2 (n = 113) and those with a BMI <25 kg/m2 (n = 279). The influence of BMI on LCR was investigated. Study 2: Patients with a BMI ≥28 kg/m2 who were scheduled to undergo LCR (n = 7, mean body weight 87.0 kg, mean BMI 33.9 kg/m2) undertook a PWLP including caloric restriction and exercise for 29.6 (15–70) days. The effects of this program were evaluated. Results: Study 1: The BMI ≥25 kg/m2 group had a prolongation of operation time and hospital stay than the BMI <25 kg/m2 group. Study 2: The patients achieved a mean weight loss of 6.9% (−6.0 kg). The mean visceral fat area was significantly decreased by 18.0%, whereas the skeletal muscle mass was unaffected. The PWLP group had a significantly lower prevalence of postoperative complications compared with the BMI ≥25 kg/m2 group. Conclusion: Obesity affected the surgical outcomes in LCR. A PWLP may be useful for obese patients undergoing LCR
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