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We experimentally studied relativistic laser propagation in preplasmas at the highest powers ever attempted-0.2 to 0.4 petawatt. We demonstrated a single conical-shaped plasma channel formation extending several hundred microns in length from the under dense to over dense plasmas, indicating whole-beam self-focused laser channeling into the high-density plasma. The channel cone was reproduced by a three dimensional particle-in-cell simulation. The confirmation of the relativistic laser channeling into high-density plasmas holds the promise of fast igniting a highly compressed fuel plasma core.

The frequency doubled laser pulses from the T3 laser system at the Center for Ultrafast Optical Science of the University Michigan1(with energy up to 1 J, a pulse duration of 400 fs, the wavelength is 0.53 ${\rm \mu} $m and the maximum intensity is $2.7\times 10^{19}$W/cm$^{2})$has been used to measure the light transmitted through thin metal targets. The intensity contrast ratio of the laser pulse was better than 10- 9which is low enough to suggest the interaction with solid density plasma without preplasma. We observed the transmittance of the laser pulse through the aluminum foil with thickness up to 4 ${\rm \mu} $m and found that this radiation is polarized and centered at 0.53 ${\rm \mu} $m. We found that for 0.8 ${\rm \mu} $m thick foils the transmission was anomalously high (${\sim}10^{ - 2}$%) and can't be explained by the skin effect for relativistic pulse.

In the interaction of a 30 fs, 40 TW Ti:sapphire Hercules laser focused to the intensity of 1019W/cm2 onto a supersonic He gas jet, we observed quasi-monoenergetic electron beams with energy up to 300 MeV and an angular divergence of 10 mrad. We found that the initial plasma density significantly affects the resultant electron beam. For plasma densities ranging between 2 $\times$1019to 3.5 $\times$1019cm- 3, quasi-monoenergetic electrons with energies from 80 to 160 MeV and a total charge of about 0.5 nC were produced. Lower plasma densities around 1.5 $\times$1019 cm- 3produced quasi-monoenergetic electron beams with higher energy, up to 320 ±50 MeV, but with a decrease of the total charge to about 5 pC. Characterization of the electron beam in terms of the electron's maximum energy, beam divergence and pointing stability is presented. The performed 2D PIC simulations show the evolution of the laser pulse in the plasma, electron injection, and the specifics of electron acceleration.

The development of unique, high-density helicon plasma sources is described. Characterization of the largest and the smallest source sizes is made along with a discussion of particle production efficiency using Ar gas. Next, we describe an application of helicon sources to plasma propulsion using a new advanced concept without any eroding electrodes, as a review of our Helicon Electrodeless Advanced Thruster (HEAT) project.

Hypotension is commonly reported in springtime when health changes, such as autonomic imbalance, are common and its symptoms may cause difficulties in daily activities. In this study, medical data from 101 outpatient clinic attendees (mean age 43.9 years; 16 males) making their first visit for hypotension symptoms, were compared with meteorological data from the clinic's location. The main symptom of hypotension was giddiness on standing. The most common coexisting conditions were gastrointestinal; e.g. gastro-oesophageal reflux disorder and irritable bowel syndrome. The 7-day moving average of total global solar radiation correlated significantly with the 7-day moving average of the number of patients with hypotension. Discriminant analysis revealed an increase in hypotension consultations in the total global solar radiation moving average range 11 – 19 MJ/m2consistent with the local spring season. Guidance — such as wearing compression stockings during springtime — may help to reduce the occurrence of clinical hypotension in susceptible patients.

A prototype X–Ystage for ultraprecise positioning composed of six pneumatic servo bearing actuators was proposed and developed. First, the basic performance of the pneumatic servo bearing actuator with a spherical aerostatic bearing was investigated before assembling it to the X–Ystage. In the actuator, pressurized air controlled by a servo valve moves an actuated spool ultraprecisely. Even under open-loop control, the actuator provided accurate replication and positioning resolution on a nanometer order. Second, the specifications of the constructed X–Ystage were evaluated, especially focusing on its minimum resolution. The minimum positioning resolution of the X–Ystage was 3 nm under the best conditions, and the positioning resolution as a practical specification was approximately 10 nm for all conditions, even without feedback controls.

The fundamental characteristics of the taper seal used to prevent oil leakage from fluid bearings were analysed theoretically and investigated experimentally. The three-dimensional flow field was theoretically analysed using numerical fluid dynamics, and the profile of the oil meniscus was calculated using the balance between the pressure field and surface tension. The oil meniscus was experimentally investigated using a micro-focus laser microscope. Three triggers for oil leakage were identified: the oil contact angle on the sleeve surface becoming excessive, the convex portion of the meniscus profile extending beyond the edge of the sleeve, and cavitation occurring in the oil.

We have investigated the field limiting ring (FLR) geometry dependence of breakdown voltage characteristics for a junction barrier Schottky (JBS)-assisted FLR SiC-SBD. The SiC-SBDs having a guard ring-assisted FLR surrounding a Schottky contact edge and an internal ring inside Schottky contact were fabricated. The breakdown voltage characteristics of the JBS-assisted FLR SiC-SBD are significantly dependent on the width, spacing, and number of FLR. The breakdown voltage characteristic is improved as either the FLR width and FLR number increase or the FLR spacing decreases. Approximately 1650 V maximal breakdown voltage, corresponding to 82% ideal breakdown voltage, is observed with seven FLRs having 5 2m width and 1 2m spacing.

The dynamic properties of both the solute and solvent of the aqueous solution of benzene, xenon and neon are calculated by the mode-coupling theory for molecular liquids based on the interaction-site model. The B-coefficients of the reorientational relaxation and the translational diffusion of the solvent are evaluated from their dependence on the concentration of the solute, and the reorientational relaxation time of water within the hydration shell is estimated based on the two-state model. The reorientational relaxation times of water in the bulk and within the hydration shell, that of solute, and the translational diffusion coefficients of solute and solvent, are calculated at 0–30 °C. The temperature dependence of these dynamic properties is in qualitative agreement with that of NMR experiment reported by Nakahara et al. (M. Nakahara, C. Wakai, Y. Yoshimoto and N. Matubayasi, J. Phys. Chem., 1996, 100, 1345–1349, ref. 36), although the agreement of the absolute values is not so good. The B-coefficients of the reorientational relaxation times for benzene, xenon and neon solution are correlated with the hydration number and the partial molar volume of the solute. The proportionality with the latter is better than that with the former. These results support the mechanism that the retardation of the mobility of water is caused by the cavity formation of the solute, as previously suggested by us (T. Yamaguchi, T. Matsuoka and S. Koda, J. Chem. Phys., 2004, 120, 7590–7601, ref. 34), rather than the conventional one that the rigid hydration structure formed around the hydrophobic solute reduces the mobility of water.

It is suggested that bulk acceleration of ions can occur in a target with density discontinuities when hot electrons are transported through the target. A foam target just belongs to such a kind of target, which is composed of irregular lamellar layers distributed randomly. To simplify the problem, we study the interaction of a high intensity laser pulse with a target consisting of regular micro-thin layers separated with a thickness of around a micrometre. Particle-in-cell simulations suggest that localized electrostatic fields with multi-peaks around the surfaces of the thin layers inside are induced when fast electrons produced are transported through such a target. These fields inhibit hot electron transport and simultaneously accelerate ions from the thin layers inside the target, forming a bulk acceleration in contrast to the surface acceleration at the front and rear sides of a thin solid target. Bulk acceleration can produce a large number of ions of moderate energy, which may be useful for applications such as fast ignition by fast protons. Experimental evidence of bulk acceleration is found with low-density foams irradiated by ultra-intense laser pulses.

Human peritoneal mesothelial cells (HPMCs) play an important role in peritoneal functions. During long term peritoneal dialysis, it has been reported that HPMCs are damaged by high glucose solution via the signal of transforming growth factor (TGF)- ß1 produced by HPMCs. In this study, we focused on the effect of hepatocyte growth factor (HGF), known as an anti-fibrotic and anti-TGF-ß1 agent, on HPMCs damaged by high glucose solution. HPMCs were isolated from specimens of the omentum from nonuremic patients after informed consent had been obtained. After confirming adhesion for 6 hours, 100 µL of DMEM with 0.5%FCS were added at different concentrations (D-glucose; 6, 30mM) with or without HGF (10, 30, 100 ng/mL) for 48 hours. We examined the effects of a high concentration of glucose and then focused on following four critical points: 1) the production of HGF from HPMCs exposed to a high concentration of glucose, 2) the expression of c-Met on HPMCs, 3) the viability of those cells, and 4) matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of metalloproteinase-2 (TIMP-2). The following significant changes are described herein: high glucose solution and TGF-ß1 i) decreased HGF production from HPMCs and ii) up-regulated expression of c-Met on HPMCs, and addition of HGF iii) restored viability of HPMCs damaged by glucose, iv) suppressed TGF-ß1 production by HGF, and v) induced up-regulation of MMP-2 and decreased TIMP-2 production by HPMCs. Levels of HGF decreased by high concentrations of glucose in the peritoneal cavity may induce the loss of HPMCs and thereby result in peritoneal fibrosis. These results suggest that HGF is an effective agent in the regeneration of peritoneal membrane damaged by high glucose solution.

Background: Tei index has been proposed as a noninvasive and simple index that enables the evaluation of global left ventricular (LV) function and prediction of patient prognosis. However, its use to predict complications with acute myocardial infarction (AMI) is not fully investigated. Therefore, the purpose of this study was to investigate whether or not LV Tei index allows noninvasive prediction of complications with AMI. Methods: In all, 80 consecutive patients with anteroseptal AMI were enrolled. LV Tei index was measured at the time of admission as (a - b)/b, where a is the interval between cessation and onset of mitral filling flow and interval b is the aortic flow ejection time. Subsequent complications including cardiac death, shock, congestive heart failure, ventricular tachycardia/fibrillation, paroxysmal atrial fibrillation/flutter, advanced atrioventricular block requiring pacing, pericardial effusion, and LV aneurysm during the 30 days after the onset of AMI were prospectively evaluated and compared with the initial Tei index at admission. Results: Complications developed in 31 of 80 (39%) patients with AMI. The Tei index was significantly increased for patients with complications compared with those without them (0.69 +/- 0.16 vs 0.50 +/- 0.11, P < .0001). When Tei index >= 0.59 was used for the criteria, the sensitivity, specificity, and overall accuracy to predict subsequent complications were 77%, 86%, and 85%, respectively. Conclusion: In patients with anteroseptal AMI, LV Tei index at arrival to the hospital in the acute phase allows noninvasive prediction of subsequent complications.

Recent progress in the physics of fast ignition of fusion targets is reviewed here. Fundamental studies on hot electron energy transport show that the scheme looks promising if the heating pulse can be guided close enough to a compressed core. The idea of using cone-guided compression was first demonstrated experimentally under a Japan–UK collaboration. The use of the gold cone was extremely successful and showed a 103 neutron increase out of CD target implosion with a 300 J/0.5 ps enforced heating laser pulse. The heated temperature was close to 1 keV. In order to increase the temperature to 10 keV, a 10 kJ PW−1 laser system is necessary. Osaka University has started constructing such a laser system.

The ultrasonic absorption spectra of aqueous solutions of polyacrylate (PA), polyphosphate (PP), and polystyrenesulfonate (PSS), neutralized by tetramethylammonium hydroxide (TMAOH), were measured. The effects of addition of tetramethylammonium chloride (TMACl) and sodium chloride (NaCl) to the polyelectrolyte solutions were investigated in the frequency range from 500 kHz to 100 MHz. Two ultrasonic relaxation processes due to the local segmental motions were observed. The relaxation frequency for TMAPP solution decreased as the ionic strength was increased by the addition of TMACl. For the other two polymer solutions, the ionic strength did not affect the relaxation spectra. The addition of NaCl led to an increase of the ultrasonic absorption, which was ascribed to ion binding. The ultrasonic absorption due to the ion binding was estimated by subtracting the contribution of the segmental motion from the measuring ultrasonic spectra. The volume changes accompanying the ion binding for polyacrylate and polyphosphate salts were estimated to be 5 and 8 cm3-mol−1, respectively.

The long-term effectiveness of zonisamide (ZNS) was evaluated in 11 patients with West syndrome (7 symptomatic) who had cessation of spasms with ZNS monotherapy. During the follow-up period (24 to 79 months, mean 53 months), this response was maintained in 7 patients (3 symptomatic, relapse rate 36), including 2 children in whom ZNS was successfully discontinued. No serious adverse reactions were noted. ZNS may be both effective and well tolerated for the treatment of West syndrome.

Abstract: A 57-year-old woman with RA of 10 years' duration presented with a history of right coxalgia. Three weeks after total hip arthroplasty, the patient developed an acute pulmonary embolism. The results of screening for hypercoagulable states revealed a protein S (PS) deficiency, and all PS values, i.e., total PS antigen, free PS antigen, and PS cofactor, were lower than the normal ranges, showing that the patient had type I PS deficiency. She had no past history of embolism or deep venous thrombosis. The values of three PS-related parameters were also lower than normal in her daughter. The responsible mutation may be located on exon 15 of genomic PS DNA, as indicated by polymerase chain reaction. We therefore diagnosed hereditary PS deficiency.

Freshness of eggplant was quantified in terms of Freshness Index (FI) as a function of surface gloss, stiffness and density ratios and prices of the same and other test samples of eggplants were ascertained in and verified from local market.

The aim was to evaluate a subtraction technique for breath-hold gadolinium enhanced three-dimensional magnetic resonance portography (3D-MRP). 26 patients with gastric and/or duodenal varices related to portal hypertension were investigated by 3D-MRP with two phase acquisitions. A partial volume maximum intensity projection (MIP) image after subtracting selective arterial phase images from subsequent portal venous phase images (subtraction 3D-MRP) was compared with the partial volume MIP without subtraction (non-subtraction 3D-MRP) to assess visualization of the portal vein and its collaterals. Subtraction 3D-MRP depicted excellent visualization of the portal vein, although this was not significantly better than non-subtraction 3D-MRP. However, subtraction 3D-MRP gave superior visualization of portal collaterals, with effective suppression of arterial and renal signal intensities, compared with non-subtraction 3D-MRP (p<0.001).

Abstract The regeneration mechanism of injured rat colonic mucosa with 1% acetic acid was certified in this study. The injured colons were studied periodically on experimental days 1, 3, 5, 7, 15, and 20 with light and scanning electron microscopy. Specimens were examined in paraffin sections stained with hematoxylin and eosin; crypts were isolated with the HCl digestion method; and three-dimensional stromal collagen tissue was prepared with the NaOH cell maceration method. Damage to the mucosal and submucosal layers peaked between the 1st and 3rd days with edema, regeneration, necrosis, and inflammation. The edema and inflammation subsided, and mucosal atrophy and crypt reduction remained at around 1 week. At 2 weeks the mucosa became thick, and crypts showed many branches in their lower two-thirds; and by 3 weeks the mucosa had recovered to almost normal. The ratio of number of crypts at the base and surface was almost 1.5 on the 15th day and 1.0 on the 20th day, suggesting that each branch progresses upward to create an independent crypt. We believe that the fission mechanism plays an important role in crypt repair after acetic acid injury of the colonic mucosa. As the proliferative zone of the colonic crypt is localized at the crypt base, fission of the crypt starting at the base and progressing up to the surface is the most reasonable and efficient mechanism for repair by increasing the number of crypts.

The acoustic properties of PMMA poly(methyl methacrylate) deformed by tensile stress were investigated by the coherent Brillouin scattering method. The ultrasonic velocities of PMMA in steady stress–strain states were measured in the frequency range of 100 MHz to 1 GHz. The ultrasonic velocities decreased with increasing strain, and the ratio of the decrease increased with increasing strain rate. This result indicates that the crazing residues still remain in the steady stress–strain states, and the amount of the residues depends upon the strain rate. The velocity dispersion was observed around 400 MHz for virgin and deformed PMMA and reproduced with a single relaxation process. The relaxation process is assigned to the γ-relaxation according to the dispersion map for methyl group relaxation in PMMA. The relaxation frequency and strength were independent of the applied stress and strain. The viscoelastic and plastic deformations have little effect on the γ-relaxation. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 978–986, 2000

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Abstract.: The purpose of this study was to demonstrate the utility of helical CT in assessing the therapeutic effects of endoscopic variceal ligation (EVL). Twenty-four patients with esophageal varices were examined. Helical scanning was initiated 60 s after intravenous injection (Iopamidol 300 mgI/ml, total 120 ml, 3 ml/s) was started. Esophageal varices were clearly depicted as high-density areas. Multiplanar reformation and 3D images demonstrated collateral circulation three-dimensionally. After EVL, mucosal high-density areas had diminished markedly, but collateral veins around the esophagus, and gastro- and/or spleno-renal shunts, were unchanged in all patients. Of 21 patients with collateral circulation, esophageal varices recurred endoscopically in 6 patients within 12 months. In 3 patients without collateral circulation, esophageal varices did not recur within 12 months. From these findings, we conclude that helical CT is a useful method for assessing the therapeutic effects of EVL.

We have studied the roles of c-Jun N-terminal protein kinase (JNK) and extracellular signal-regulated protein kinase (ERK) cascade in both the cisplatin-resistant Caov-3 and the cisplatin-sensitive A2780 human ovarian cancer cell lines. Treatment of both cells with cisplatin but not transplatin isomer activates JNK and ERK. Activation of JNK by cisplatin occurred at 30 min, reached a plateau at 3 h, and declined thereafter, whereas activation of ERK by cisplatin showed a biphasic pattern, indicating the different time frame. Activation of JNK by cisplatin was maximal at 1000 microM, whereas activation of ERK was maximal at 100 microM and was less at higher concentrations, indicating the different dose dependence. Cisplatin-induced JNK activation was neither extracellular and intracellular Ca(2+)- nor protein kinase C-dependent, whereas cisplatin-induced ERK activation was extracellular and intracellular Ca(2+)- dependent and protein kinase C-dependent. A mitogen-activated protein kinase/extracellular signal-regulated kinase kinase inhibitor, PD98059, had no effect on the cisplatin-induced JNK activity, suggesting an absence of cross-talk between the ERK and JNK cascades. We further examined the effect of each cascade on the viability following cisplatin treatment. Either exogenous expression of dominant negative c-Jun or the treatment by PD98059 induced sensitivity to cisplatin in both cells. Our findings suggest that cisplatin-induced DNA damage differentially activates JNK and ERK cascades and that inhibition of either of these cascades sensitizes ovarian cancer cells to cisplatin.

Aims/hypothesis. Prolonged poor glycaemic control in patients with Type II (non-insulin-dependent) diabetes mellitus often causes pancreatic beta-cell dysfunction accompanied by decreases in insulin biosynthesis and beta-cell proliferation. This is well known as a clinical concept called glucose toxicity. Whereas oxidative stress is provoked under diabetic conditions, we examined the possible implication of cyclin-dependent kinase (Cdk) inhibitor p21 (WAF1/CIP1/Sdi1) in beta-cell dysfunction mediated by oxidative stress. Methods. Oxidative stress was induced in isolated rat pancreatic islet cells by treatment with H2O2and mRNA expression of p21 and insulin was examined by northern blot analyses. Also, the expression of p21 and insulin mRNA was examined in Zucker diabetic fatty rat. In islet cells p21 was overexpressed using adenovirus and its effect on insulin gene transcription was examined. Results. When oxidative stress was charged on isolated rat pancreatic islet cells, p21 mRNA expression was induced whereas insulin mRNA was decreased. Also, when diabetes developed in Zucker diabetic fatty rats, p21 expression was induced and the insulin mRNA expression was reduced. As support for the implication of p21 in impairment of beta-cell function, the p21 overexpression in the islet cells suppressed the insulin gene transcription. Conclusions/interpretation. The expression of cyclin-dependent kinase inhibitor p21, which can be induced by oxidative stress, increases in pancreatic islet cells upon development of diabetes. By suppressing cell proliferation and insulin biosynthesis, the p21 induction is likely to be implicated in the beta-cell glucose toxicity. [Diabetologia (1999) 42: 1093–1097}Aims/hypothesis. Prolonged poor glycaemic control in patients with Type II (non-insulin-dependent) diabetes mellitus often causes pancreatic beta-cell dysfunction accompanied by decreases in insulin biosynthesis and beta-cell proliferation. This is well known as a clinical concept called glucose toxicity. Whereas oxidative stress is provoked under diabetic conditions, we examined the possible implication of cyclin-dependent kinase (Cdk) inhibitor p21 (WAF1/CIP1/Sdi1) in beta-cell dysfunction mediated by oxidative stress. Methods. Oxidative stress was induced in isolated rat pancreatic islet cells by treatment with H2O2and mRNA expression of p21 and insulin was examined by northern blot analyses. Also, the expression of p21 and insulin mRNA was examined in Zucker diabetic fatty rat. In islet cells p21 was overexpressed using adenovirus and its effect on insulin gene transcription was examined. Results. When oxidative stress was charged on isolated rat pancreatic islet cells, p21 mRNA expression was induced whereas insulin mRNA was decreased. Also, when diabetes developed in Zucker diabetic fatty rats, p21 expression was induced and the insulin mRNA expression was reduced. As support for the implication of p21 in impairment of beta-cell function, the p21 overexpression in the islet cells suppressed the insulin gene transcription. Conclusions/interpretation. The expression of cyclin-dependent kinase inhibitor p21, which can be induced by oxidative stress, increases in pancreatic islet cells upon development of diabetes. By suppressing cell proliferation and insulin biosynthesis, the p21 induction is likely to be implicated in the beta-cell glucose toxicity. [Diabetologia (1999) 42: 1093–1097}