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Using the 160-m-long flume at Tsukuba University we undertook an experiment to provide a first estimate of the virtual velocity of sand in the size range 0.5 – 2.0 mm. For the flow velocity used in our experiment this sediment-size range would conventionally be regarded as suspended sediment. The virtual velocity is found to be 37-41 % of the flow velocity. Paradoxically, virtual velocity decreases as particle size decreases. Such a lower virtual velocity of finer sediment is not inconceivable. First, trapping of the sediment appears to be a function of bed roughness, and there is a probable relationship between bed roughness and trapping efficiency for particles of different sizes. Secondly, finer particles are more likely to find sheltered positions on a rough bed and thus experience lower mobility, relative to the more exposed coarser grains, as observed for bedload transport. Thirdly, the virtual velocity of particles undergoing bedload transport has been found, in some instances, to be lower for finer clasts. We combine our data with previous studies of virtual velocity of bedload to develop, for the first time, an hypothesis for an holistic analysis of sediment movement in rivers.

Aim: Non-invasive steatosis-quantifying methods are required for non-alcoholic fatty liver disease (NAFLD) patients in order to monitor disease severity and assess therapeutic efficacy. Controlled attenuation parameter (CAP) evaluated with vibration-controlled transient elastography can predict the presence of steatosis, but its application to absolute hepatic fat quantitation remains unclear. The aim of this st\udy was to examine whether CAP is correlated with real hepatic fat content in NAFLD patients. Methods Eighty-two NAFLD patients who had undergone percutaneous liver biopsy were enrolled. CAP was measured using FibroScan® just before liver biopsy. The percentage of fat droplet area to hepatocyte area in biopsied specimen was determined morphometrically using computerized optical image analyzing system. The correlation between CAP and liver histology was examined. Results CAP showed an excellent correlation with actual liver fat percentage in the NAFLD patients with body mass index (BMI) of less than 28 kg/m2 (r = 0.579, P

We developed a portable device made of poly(dimethylsiloxane) (PDMS)/polymethylmethacrylate (PMMA) for long-term 3D cell culture of vascular endothelial cells for the development of a vascular network and evaluated the device under different transitions between normoxia and hypoxia with good optical accessibility. The combination of a nested reservoir device and a bicarbonate/ascorbate buffer system accomplished on-chip incubation with 4.91 &plusmn, 0.86% pO2 and 5.19 &plusmn, 1.70% pCO2 for up to 10 days. Seventy-two hours of normoxic incubation preceding hypoxic culture increased the cell viability, network formation, and size and stability of the resulting lumens compared with those completely maintained in normoxia for the same total duration. We employed different parameters of the network (e.g., total mesh area, total length, number of branches, among others) for the comparison of different oxygen treatments in the device. The differential effect of hypoxic conditions based on the maturity of the vessels may be used as an external factor to improve vascular development in vitro.

The development of bedforms under unidirectional, oscillatory and combined-flows results from temporal changes in sediment transport, flow and morphological response. In such flows, the bedform characteristics (for example, height, wavelength and shape) change over time, from their initiation to equilibrium with the imposed conditions, even if the flow conditions remain unchanged. These variations in bedform morphology during development are reflected in the sedimentary structures preserved in the rock record. Hence, understanding the time and morphological development in which bedforms evolve to an equilibrium stage is critical for informed reconstruction of the ancient sedimentary record. This article presents results from a laboratory flume study on bedform development and equilibrium development time conducted under purely unidirectional, purely oscillatory and combined-flow conditions, which aimed to test and extend an empirical model developed in past work solely for unidirectional ripples. The present results yield a unified model for bedform development and equilibrium under unidirectional, oscillatory and combined-flows. The experimental results show that the processes of bedform genesis and growth are common to all types of flows, and can be characterized into four stages: (i) incipient bedforms; (ii) growing bedforms; (iii) stabilizing bedforms; and (iv) fully developed bedforms. Furthermore, the development path of bedform; growth exhibits the same general trend for different flow types (for example, unidirectional, oscillatory and combined-flows), bedform size (for example, small versus large ripples), bedform shape (for example, symmetrical or rounded), bedform planform geometry (for example, two-dimensional versus three-dimensional), flow velocities and sediment grain sizes. The equilibrium time for a wide range of bed configurations was determined and found to be inversely proportional to the sediment transport flux occurring for that flow condition.

Background & Aims Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by portal inflammation and immune-mediated destruction of intrahepatic bile ducts that often leads to liver decompensation, and liver failure. Although the biochemical response to ursodeoxycholic acid (UDCA) can predict disease outcome in PBC, few biomarkers have been identified as prognostic tools applicable prior to UDCA treatment. We therefore sought to identify such indicators of long-term outcome in PBC in the Japanese population. Methods The pre-biopsy serum samples and subsequent clinical data of 136 patients with PBC treated with UDCA were analyzed over a median follow-up period of 8.8 years. Serum levels of biomarkers related to microbial translocation (sCD14, EndoCAb, and I-FABP) were measured along with those of 33 cytokines and chemokines and additional autoantibodies. Associations between the tested parameters and the clinical outcomes of liver decompensation and liver-related death/liver transplantation were evaluated using the Cox proportional hazards model with stepwise methods and Kaplan-Meier analysis. Results Elevated levels of serum IL-8, and sCD14 before UDCA therapy were significantly associated with both liver decompensation and liver-related death/liver transplantation. In multivariate analyses, IL-8 ≥ 46.5 pg/mL or sCD14 ≥ 2.0 μg/mL at enrollment demonstrated the same results. Kaplan-Meier analysis also revealed IL-8 and sCD14 to be significantly associated with a poor outcome. sCD14 was significantly correlated with IL-8. EndoCAb and I-FABP were not related to disease outcome. Conclusions Serum IL-8 and sCD14 levels before UDCA therapy represent noninvasive surrogate markers of prognosis in patients with PBC. This article is protected by copyright. All rights reserved.

ウェーブリップルは，与えられた振動流条件と堆積物特性の下で，安定的に持続する特定の形状，サイズ，波峰線オリエンテーションを有する．振動流条件が変わるとウェーブリップルはその条件下での定常状態の獲得をめざして遷移する．新たな振動流方向が初期リップルの波峰線と直交する場合，遷移過程は（1）初期リップルと定常リップルの波長の大小関係，（2）振動流の非対称性，（3）堆積物粒径に依存する．とくに，初期リップルの波長が定常リップルのそれよりも大きいと，初期リップルの形状の一部をとどめる遷移リップルが一時的に現れる．地層に見られる遷移リップルは，地層形成時の振動流条件を推測する重要な手がかりとなりうる．

In this paper, nanobubble shrunk from microbubble generated by electrolysis was observed by optical microscope in order to distinguish a bubble from impurities or contamination in the water. To keep microbubbles in focus, it is necessary to generate microbubble whose diameter is less than 5μm in focal position directly since its rising velocity is negligibly small and shrink rapidly. Therefore, diameter distribution of bubble generated by electrolysis was firstly investigated under the different configurations of electrode diameter, concentration of solution and voltage. In the result, when diameter of electrode was less than 1μm, distribution of bubble diameter was decreased to generate smaller bubble. Observation of Brownian motion of nanobubble was succeeded. Root mean square of displacement and diameter of nanobubble were simultaneously measured and compared with a behavior of the ZnO solid particle. As a consequence, root mean square of displacement of bubble is smaller than that of ZnO particle due to different structure of interface.

A 33-year-old man presented with pain and palsy of the leg in 2008 for treatment of hepatocellular carcinoma with huge distant metastases. The patient's tumors had slowly enlarged despite several treatments. Oral administration of sorafenib at 800 mg/day with careful observation was commenced in 2009. Laboratory investigations on day 7 showed massive tumor lysis. An abdominal CT showed multiple low density areas and tumor markers decreased, indicating extended tumor necrosis. In conclusion, clinicians should bear in mind not only the published adverse effects, but also massive tumor lysis, when treating patients with large tumor burden by sorafenib., Article, INTERNAL MEDICINE. 49(11):991-994 (2010)

Setting the experimental condition under partially standing wave, which little attention has been given to in spite of being found in nature, a series of wave-flume experiments of development of ripples were performed, using four kinds of sand with different diameters (0.15 mm≤D≤1.23 mm). Ripples developed under partially standing waves showed the cross-shore variations in ripple spacing, asymmetry and crest-line pattern, depending on the positions to ‘nodes’ and ‘anti-nodes’, and on grain size. Ripple spacing was the largest under nodes and the smallest under anti-nodes and was associated with the variation in the orbital diameter. Ripples with rounded crests and bifurcated crest-lines tended to form under anti-nodes.

OBJECTIVES:Noninvasive markers of liver fibrosis in patients with primary biliary cirrhosis (PBC) are needed for predicting disease progression. As the Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+-M2BP) was recently established as a liver fibrosis glycobiomarker in chronic hepatitis C, we assessed its efficacy in evaluating liver fibrosis stage and disease progression in PBC.METHODS:A total of 137 patients with PBC who underwent liver biopsy and serological tests for WFA+-M2BP were enrolled. All patients were treated with ursodeoxycholic acid. Clinical data were compared with those for other noninvasive markers (aspartate aminotransferase-to-platelet ratio, FIB-4 index, aspartate aminotransferase/alanine aminotransferase ratio, Forn’s index, and Mayo score) for estimating liver fibrosis using receiver operating characteristic analysis. The association between WFA+-M2BP and clinical outcome (liver decompensation, liver transplantation, or death) was evaluated using the Cox proportional hazards model with stepwise method.RESULTS:WFA+-M2BP was independently associated with liver fibrosis stage as determined by liver biopsy. The cutoff values of WFA+-M2BP for fibrosis stages ≥F1, ≥F2, ≥F3, and F4 were 0.7, 1.0, 1.4, and 2.0, respectively. The area under the receiver operating characteristic curve values for significant fibrosis, severe fibrosis, and cirrhosis were 0.979, 0.933, and 0.965, respectively. WFA+-M2BP was significantly superior to the other indices for the determination of significant and severe fibrosis stages. Furthermore, the WFA+-M2BP level at enrollment was strongly and independently associated with clinical outcome (hazard ratio 18.59, P=0.021).CONCLUSIONS:Baseline measurements of WFA+-M2BP represent a simple and reliable noninvasive surrogate marker of liver fibrosis and prognosis in patients with PBC., Article, AMERICAN JOURNAL OF GASTROENTEROLOGY.110(6):857-864(2015)

There are many sand banks in Seto Inland Sea, making patchy shallow zones less than 10 m deep. Due to the shallow environment, the surface sediment on the sand banks in the Hojo area, in the southern part of Aki Nada, Shikoku Island, Japan, often has a larger amount of benthic microalgae than other areas. We hypothesized that benthic microalgae contributed to the secondary production of coastal waters around sand bank areas, and investigated the food-web structure of the Hojo area using stable isotopes in early summer, mid summer and fall. Mean carbon isotopic signatures of several consumers in early summer ( 16.9 to 15.1‰ for polychaeta; 17.3 to 13.9‰ for brachyuran crabs; 17.2 to 15.3 for fish) and fall ( 16.2 to 14.3‰ for shrimps; 14.0 to 11.2‰ for brachyuran crabs) were more enriched than that of the particulate organic materials of the surface water around sand banks (mainly phytoplankton) ( 20.5 0.0‰ in early summer and 18.3 0.1‰ in fall). Organic materials attached to cobbles, representative of benthic microalgae, showed similar or more enriched signatures than consumers ( 14.7 0.0‰ in early summer and 10.3 0.0‰ in fall). These results suggest that benthic microalgae on the sand bank contribute greatly to the secondary or higher production of coastal waters in Hojo area.

The lack of systematic studies of the influence of bottom irregularities on ripple initiation led to a series of wave-flume experiments with the purpose of exploring a general relationship. Three types of sand beds with different degrees of roughness were prepared for the experiments: flat, notched, notch-mounded beds. Three kinds of well-sorted sands with different diameters were used for the bed material: fine, medium, and coarse sands. With combinations of waves, water depth, sand, and bed roughness, 248 experimental runs were carried out. Data were analyzed considering (1) the mobility of sediment, expressed in terms of the mobility number, M, (2) the degree of bed roughness, represented by the Reynolds number, Re, and (3) the asymmetry of flow field due to nonlinearity of waves, represented by the relative water depth, kh (= 2πh/L; h = water depth and L = wavelength). The result showed that the threshold for rippling is described by M = 2 + A exp B, where A = 5.7 (3.79/(kh + 0.65) − 1) and B...

Laboratory experiments using a wave flume were designed to examine the threshold condition for ripple formation under asymmetrical oscillatory flows on an artificially roughened bed. Three types of sand beds were prepared in the experiments: they were flat, notched, and notch-mounded beds with bed roughness increasing in this order. The beds were constructed with three kinds of well-sorted sand with similar density, but different diameters. Data analyses were made using the two dimensionless parameters: the mobility number, M, a simplified form of the Shields number, and the Ursell number, U, a surrogate for asymmetry of flow field. The result confirmed that the threshold for ripple initiation is decreased with increasing bed perturbation and that as the bed perturbation increases, the dependency of this threshold on the flow asymmetry becomes less and finally null for the notch-mounded bed. This relationship is quantified by the following equations: M=17−14.5e−0.03U on the flat bed, M=5.0−2.5e−0.1U for the notched bed, and M=2.5 for the notch-mounded bed. A comparison between the previous field data and the present laboratory findings indicates that the threshold in the notch-mounded bed experiment, M=2.5, seems to provide a critical condition for rippling in the natural environment.

The development of simple, noninvasive markers of liver fibrosis is urgently needed for primary biliary cirrhosis (PBC). This study examined the ability of several serum biomarkers of cell death to estimate fibrosis and prognosis in PBC. A cohort of 130 patients with biopsy-proven PBC and 90 healthy subjects were enrolled. We assessed the utility of the M30 ELISA, which detects caspase-cleaved cytokeratin-18 (CK-18) fragments and is representative of apoptotic cell death, as well as the M65 and newly developed M65 Epideath (M65ED) ELISAs, which detect total CK-18 as indicators of overall cell death, in predicting clinically relevant fibrosis stage. All 3 cell death biomarkers were significantly higher in patients with PBC than in healthy controls and were significantly correlated with fibrosis stage. The areas under the receiver operating characteristic curve for the M65 and M65ED assays for differentiation among significant fibrosis, severe fibrosis, and cirrhosis were 0.66 and 0.76, 0.66 and 0.73, and 0.74 and 0.82, respectively. In multivariate analysis, high M65ED (hazard ratio 6.13; 95% confidence interval 1.18-31.69; P = 0.031) and severe fibrosis (hazard ratio 7.45; 95% confidence interval 1.82-30.51; P = 0.005) were independently associated with liver-related death, transplantation, or decompensation. High serum M65ED was also significantly associated with poor outcome in PBC (log-rank test; P = 0.001). Noninvasive cell death biomarkers appear to be clinically useful in predicting fibrosis in PBC. Moreover, the M65ED assay may represent a new surrogate marker of adverse disease outcome.

At least two different protease pathways have been implicated in the degradation that is required to control the eukaryotic cell cycle; these two pathways center on the activities of ubiquitin/proteasome and cysteine protease. The proteasome inhibitors, lactacystin and AcLLnL and the cysteine protease inhibitor E-64-d were tested for their ability to inhibit the cell cycles of Xenopus embryos. Lactacystin, AcLLnL and E-64-d all caused the complete arrest of the cell cycle. To define the specific cell cycle processes that were affected by the two inhibitors, we performed a cytological analysis. Inhibition of the cell cycle by lactacystin and E-64-d occurred during prophase and metaphase. The number of cells that arrested in prophase was 1.4-times higher in the E-64-d-treated group than in the control group and the number of arrested cells in the lactacystin-treated group was 1.4-times higher than in the E-64-d-treated group. The number of cells that arrested in metaphase was 3-to-4-times higher in the E-64-d and lactacystin groups than in the control group. These results indicate that both cysteine protease(s) and proteasomes are involved in the prophase and metaphase stages of cell division.

Certain clinical aspects of vivax malaria are no longer defined as benign. We present a case of vivax malaria with three relapses in a pregnant Japanese woman who had returned to Japan from the Comoros Islands in East Africa. Data on the successful delivery, examination of Duffy-blood group antigen, and microscopic findings of growing stages of Plasmodium vivax are thought to be of considerable interest.