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Immature hepatitis B virus (HBV) captures nucleotides in its capsid for reverse transcription. The nucleotides and nucleotide analogue drugs, which are triphosphorylated and negatively charged in the cell, approach the capsid via diffusion and are absorbed into it. In this study, we performed a long-time molecular dynamics (MD) calculation of the entire HBV capsid containing pregenome RNA to investigate the interactions between the capsid and negatively charged substances. Electric field analysis demonstrated that negatively charged substances can approach the HBV capsid by thermal motion, avoiding spikes. The substances then migrate all over the floor of the HBV capsid. Finally, they find pores through which they can pass through the HBV capsid shell. Free energy profiles were calculated along these pores for small ions to understand their permeability through the pores. Anions (Cl-) showed higher free energy barriers than cations (Na+ and K+) through all pores, and the permeation rate of Cl- was eight times slower than that of K+ or Na+. Furthermore, the ions were more stable in the capsid than in the bulk water. Thus, the HBV capsid exerts ion selectivity for uptake and provides an environment for ions, such as nucleotides and nucleotide analogue drugs, to be stabilized within the capsid.

Immature hepatitis B virus (HBV) captures nucleotides in its capsid for reverse transcription. The nucleotides and nucleotide analogue drugs, which are triphosphorylated and negatively charged in the cell, approach the capsid via diffusion and are absorbed into it. In this study, we performed a long-time molecular dynamics (MD) calculation of the entire HBV capsid containing pregenome RNA to investigate the interactions between the capsid and negatively charged substances. Electric field analysis demonstrated that negatively charged substances can approach the HBV capsid by thermal motion, avoiding spikes. The substances then migrate all over the floor of the HBV capsid. Finally, they find pores through which they can pass through the HBV capsid shell. Free energy profiles were calculated along these pores for small ions to understand their permeability through the pores. Anions (Cl-) showed higher free energy barriers than cations (Na+ and K+) through all pores, and the permeation rate of Cl- was eight times slower than that of K+ or Na+. Furthermore, the ions were more stable in the capsid than in the bulk water. Thus, the HBV capsid exerts ion selectivity for uptake and provides an environment for ions, such as nucleotides and nucleotide analogue drugs, to be stabilized within the capsid.

This paper focuses on the hypothesis that some of elemental motions are classified into several groups which may correspond to cultural, geographical or generational human groups. We propose a method to find characteristic motions which express differences of different human groups. We used a method which describes an activity as a sequence of symbols. The proposed method discovers characteristic patterns by observing relation among frequent sub-sequences in the sequences. We applied the method to radio gymnastic exercises, and discovered characteristic patterns that group the exercisers.

A novel final focus system design featuring the Local Chromaticity Correction scheme has beenproposed for ILC. This is to be verified at ATF2, a test facility for ILC, through focusing an e-beam down to the design vertical beam size (“σy”) of 37 nm. Shintake Beam Size Monitor (“IPBSM”),installed at the virtual interaction point of ATF2, is the only existing device capable of measuring σy below 100 nm, making it indispensable for achieving the goals of ATF2 and a strong candidate for R&D at future linear colliders. This is attributed to its ingenious technique of scanning the phase oflaser interference fringes relative to the e-beam. Beam sizes are derived from the resulting Compton signal modulation measured by a downstream detector. Having been upgraded in a variety of ways since its first debut at FFTB, Shintake Monitor is capable of measuring a wide range of σy from 25 nm to 6 μm with better than 10% resolution. This paper describes the system's design, role in beam tuning, and various hardware upgrades to further improve its performance.

Background In long-term peritoneal dialysis, myofibroblast-like cells found in the interstitium of the peritoneum are assumed to be a transformed type of mesothelial cell—epithelial-mesenchymal transition-positive [EMT(+)] human peritoneal mesothelial cells (HPMCs)—because they express a mesothelial marker, cytokeratin. However, no direct evidence about how these cells are able to invade from the mesothelium has yet been obtained. Aim In this study, we aimed to verify whether EMT(+) HPMCs would, in vitro, invade three-dimensionally along certain chemotactic factors. Methods We used reverse-transcriptase polymerase chain reaction to measure expression of Snail, E-cadherin, α5-integrin, and matrix metalloproteinase 2 (MMP2) messenger RNA (mRNA) in HPMCs exposed to 10 ng/mL transforming growth factor β1 (TGFβ1) and how that expression corresponds to cell motility, as represented by a video movie. We used the Transwell (12 μm pore diameter: Sigma-Aldrich, Tokyo, Japan) to construct a three-dimensional (3D) cell migration chamber. In the lower chamber, a concentration gradient of fibronectin (FN) or albumin(Alb) was formed in 0.1% type I collagen by diffusion ( C0 = 22 nmol/L; concentration gradient: C / C0 = 0.7). All cells beneath the membrane were counted 72 hours after 5x104 EMT(+) HPMCs (HPMCs after a 48-hour exposure to 10 ng/mL TGFβ1) had been spread in the upper chamber. Results After 72 hours, the increased motility of HPMCs resulting from their exposure to 10 ng/mL TGFβ1 had returned to baseline, but they retained an elongated morphology. Expression of Snail and MMP2 mRNA reached maximum at 24 hours. Expression of E-cadherin declined, and expression of α5-integrin increased continuously. In the 3D invasion study, significantly enhanced invasion by EMT(+) but not EMT(-) HPMCs was clearly seen in the presence of a FN concentration gradient ( p < 0.01), although invasion by EMT(+) and EMT(-) HPMCs in the absence of a FN concentration gradient was not statistically significantly different. Compared with the EMT(+) control (no concentration gradient), invasion by EMT(+) HPMCs was 2.1 ± 0.5 times (p < 0.05) and 1.4 ± 0.4 times (p = nonsignificant) higher along the FN and Alb concentration gradients respectively. Increased invasion along the FN concentration gradient was significantly inhibited (p < 0.05) when the HPMCs were pre-incubated with 5 μg/mL RGDS (a blocker for α5-integrin to FN). Conclusions We conclude that EMT(+) HPMCs invade collagen gel along the FN concentration gradient because of specific binding to RGDS receptors, which bind integrins such as α5-integrin, upregulating invasion-related gene expression associated with synthesis of the cytoskeleton protein α smooth muscle actin.

Hydrodynamically air-lubricated foil journal bearings are prospective applicants for machine elements that can support a small-sized rotor of high-speed rotary machinery, such as a micro gas turbine. The smooth surface of the bearing deforms elastically, depending on an applied bearing load, since it is a flexible foil that is supported elastically. Bump foil journal bearing is a kind of the bearings. The bearing consists of two foils. One is cylindrical and named as a top foil. The other is corrugated and named as a bump foil. The top foil is supported elastically by the bump foil. As the foils are forced into the bearing sleeve in assembling the bearing, the top foil deforms due to the assembly preload from the bump foil. The previous prediction was conducted without the preload being considered. This study aims at predicting the maximum load capacity of the bearing with the preload, by using two models. One corresponds to the bearing with an infinitely static friction between the two foils and the other to the bearing without the friction. It is found that each of the bearing design variables has an effect on the capacity obtained with the preload being considered.

Ion Back Flow (IBF) suppression is essential to avoid a space-charge distortion of the electric field under a high rate condition for the Time Projection Chamber (TPC). We developed Thick COBRA GEMs to investigate a capability of IBF suppression. It was found that the COBRA GEM can suppress IBF more effectively compared to a standard GEM. IBF reaches about 0.1–0.5% and energy resolution (σ) is ∼ 20% with a stack configuration consisting of one standard GEM facing to the drift field and two COBRA GEMs.

My presentation focuses on the Shintake (Beamsize) Monitor which can measure nanometer electron beam sizes. The Shintake Monitor is installed in the Accelerator Test Facility 2 (ATF2) at KEK, Japan. ATF2 is a realistic scaled down model of the final focus system for the International Linear Collider. The final focusing scheme named the Local Chromaticity Correction will be tested for the first time in the world. The vertical design beam size at the focal point (virtual interaction point) is 37 nm. Shintake monitor has been designed to measure a beamsize down to 20 nm. It employs the interference pattern made by splitting laser beams and crossing them at the focal point of the electron beam. In their intersecting region, the electromagnetic fields of the two laser beams form a standing wave (interference fringe). The probability of the Compton scattering varies according to the phase of the standing wave where the electrons pass through. Then the total energy of photons from the Compton scattering is measured in a multi-layered ganma ray detector located downstream from the interaction point. This scheme was originally proposed by T. Shintake whose team measured a beamsize of approximately 65 nm with 10 percent resolution at FFTB, SLAC, a former test facility for the ILC. We upgraded this monitor to measure the even smaller beam sizes to be available at ATF2. The laser wavelength has been modified from 1064 nm to 532 nm using a second harmonics generator. The laser optics was newly designed and constructed by implementing a laser wire scheme to measure a larger horizontal beam size, and by enabling different crossing angles of split laser beams to measure a wide (diverse) range of vertical beam sizes. The gamma detector for Shintake monitor has also been newly developed. We evaluated the performance of Shintake monitor with a beam of several microns in size and confirmed its consistency with wire scanner measurements. The expected performance of the Shintake monitor and the current status of the electron beam at ATF, achieved a record in beam size history and near future plan for 37 nm beam size measurement will be mentioned.