Impact of Serum Chemerin Levels on Liver Functional Reserves and Platelet Counts in Patients with Hepatocellular Carcinoma

Obesity-related metabolic abnormalities, including adipokine imbalance and chronic inflammation, are involved in liver carcinogenesis. Chemerin, a novel adipokine, plays a critical role in adipogenesis, energy metabolism, and inflammation. We evaluated the impact of serum chemerin levels on liver functional reserves in hepatocellular carcinoma (HCC) patients and on the recurrence and prognosis of HCC. This study included 44 patients with any stage of HCC who underwent curative treatment at Gifu Municipal Hospital (Gifu, Japan) between 2006 and 2007. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Serum albumin levels (Pearson’s correlation coefficient; r = 0.3110, p = 0.0399), platelet counts (r = 0.4159, p = 0.0050), and prothrombin times (r = 0.3775, p = 0.0115) were significantly correlated with serum chemerin levels in patients with HCC, and they were inversely correlated with Child-Pugh scores (r = −0.3732, p = 0.0126), serum alanine aminotransferase levels (r = −0.3864, p = 0.0105), and total bilirubin levels (r = −0.4023, p = 0.0068). Among these variables, a multiple comparison test identified that platelet counts and total bilirubin levels were associated with serum chemerin levels (p < 0.0083). No significant correlation was found between serum chemerin levels and recurrence-free survival (p = 0.3691) or overall survival (p = 0.7916). In HCC patients, serum chemerin concentrations were correlated with liver functional reserves and platelet counts, but not with recurrence or prognosis.     

Navigation behavior based on self-organized spatial representation in hierarchical recurrent neural network

ABSTRACT

A cognitive map is an internal model of the external world and contains the spatial representation of the surrounding environment. The existence of the cognitive map was first identified in rats; rats can navigate to their desired destination using cognitive maps while dealing with environmental uncertainty. We performed a mobile robot navigation experiment where obstacles were randomly placed using hierarchical recurrent neural network (HRNN) with multiple timescales. The HRNN was trained to navigate the mobile robot to the destination indicated by a snapshot image. After the training, the HRNN was able to successfully avoid the obstacles and navigate to the destination from any location in the environment. Analysis of the internal states of the HRNN showed that the module with fast timescale handles obstacle avoidance and the one with slow timescale has spatial representation corresponding to the spatial position of the destination. Moreover, in the experiment wherein the novel path appeared, the trained HRNN performed shortcut behavior. The shortcut behavior shows that the HRNN performed navigation using the self-organized spatial representation in the slow recurrent neural network. This indicates that training of goal-oriented navigation, i.e. the navigation motivated by a snapshot image of the destination results in the self-organization of cognitive map-like representation.     

Fabrication of fluorine-terminated diamond-like carbon thin film using a hyperthermal atomic fluorine beam

Surface modification of diamond-like carbon (DLC) film was performed using a hyperthermal atomic fluorine beam on the purpose of production of hydrophobic surface by maintaining the high hardness of DLC film. By the irradiation of atomic fluorine beam of a 1.0 × 10²⁰ atoms/cm², the contact angle of a water drop against the DLC surface increased from 73° to 111°. The formation of CF₃, CF₂ and CF bonding on the modified DLC surface was confirmed from the measurements of X-ray photoelectron spectra and near-edge X-ray absorption fine structure spectra. Irradiation of hyperthermal atomic fluorine beam was concluded to produce insulator fluorine-terminated DLC film, which has high F content on the surface, by the taking of the use of neutral atomic beam as a fluorine source.     

Slider Dynamics over a Discrete Track Medium with Servo Patterns

The dynamic characteristics of a slider flying over various servo patterns on a discrete track medium surface were investigated. The investigation shows that the air-flow field is disturbed and causes flying amplitude during the transition from grooved longitudinal discrete tracks to a transversal and near-random pattern in the servo field. The effects of the parameters that define the servo pattern including land-area ratio of burst patterns, groove depth, servo-pattern frequency, and the lengths of synchronization (sync), servo address mark (SAM), padding (PAD) blocks, and burst pattern type—on the flying height responses were evaluated. The evaluation results indicate that the flying height amplitude depends on servo-pattern frequency, burst land-area ratio, groove depth, and the lengths of the sync, SAM, and PAD block and burst pattern type. Amplitude of a slider flying over a servo pattern therefore can be reduced by optimizing the servo-pattern design from the viewpoint of these parameters. Moreover, flying-height responses over servo patterns with thermal flying height control (TFC) power were studied and compared with those without TFC power.     

Experimental study on relationship between heat parameter and angular distortion

It is well known that weld residual stress and distortion should be controlled appropriately for structural integrity. Recently, it has become much more necessary to control weld distortion to highly improve manufacturing efficiency. Various studies on control of weld distortion had been conducted based on clarification of influential dominant factors for that. The influential dominant factors had been studied from a viewpoint of temperature distribution in plate thickness section. Without considering moving the weld heat source, the temperature distribution is controlled by weld heat input (Q_net) per weld length. Angular distortion, which is controlled by temperature distribution along the direction of plate thickness (h), is controlled by heat input parameter (Q_net/h²). However, it has recently become known that the conventional results cannot be applied to all welding processes because such processes are becoming more diversified. It is significant for more accurate control of angular distortion to investigate once again the relationship between the heat input parameter and angular distortion. In this study, a series of experiments on the relationship between heat input parameter and angular distortion are carried out. The effects of welding current and welding speed are investigated individually in both TIG and MAG welding. The difference between these welding methods is also investigated. Based on the result, the effects of them are discussed in relation to temperature distribution during welding. It is considered that angular distortion is affected by temperature distribution not only in plate thickness section but also along welding direction. So, angular distortion is not always controlled by only the conventional heat input parameter because the heat input parameter is proposed as the influential dominant factor for temperature distribution in plate thickness section. It is concluded that generation characteristics of inherent strain should be considered in relation to three-dimensional temperature distributions during welding for more accurate control of angular distortion.     

Study on prevention of angular distortion in fillet-welded T-joint by welding with a trailing reverse-side gas heating

Reduction or control of angular distortion without additional processes is demanded because it takes a lot of time and effort to correct the angular distortion of fillet-welded T-joints. In this study, the reduction or control of angular distortion of both sides of a fillet-welded T-joint by welding with trailing reverse-side gas heating was investigated through a welding experiment and its numerical simulation. First, the effect of gas heating position and intensity on the reduction in angular distortion was experimentally investigated using a gas burner. The results showed that angular distortion became smallest when reverse-side heating using the gas burner was located 50 mm backward of the welding torch. Also, the concentrated gas flame with increased propane and oxygen gas flow was effective for reducing angular distortion. It was clarified that the angular distortion could be controlled completely with an appropriate reverse-side gas heating condition. Next, the numerical simulation model of welding and gas heating was constructed based on comparison with the measured temperature histories and angular distortion. Through the numerical simulation of welding with a trailing reverse-side gas, more detailed understanding of the effect of gas heating condition on reduction in angular distortion was developed. In addition, it was confirmed that the gas heating position for the smallest angular distortion is dependent on the temperature distribution along the thickness of the flange plate.     

Deoxidation of Ti Melt by Newly Developed Two-Step Plasma Arc Melting Process Using Hydrogen

Metallurgical and Materials Transactions B - A two-step plasma arc melting process, comprising a first step under Ar-30&nbsp;pct H2 gas flow and the second step under Ar gas flow, has been...     

Cancer chemoprevention with green tea catechins by targeting receptor tyrosine kinases

Recent studies indicate that receptor tyrosine kinases (RTKs), which play important roles in cell proliferation, are one of the possible targets of green tea catechins (GTCs) in cancer cell growth inhibition. (-)-Epigallocatechin-3-gallate (EGCG), the major catechin in green tea, inhibits cell proliferation and induces apoptosis in various types of cancer cells, including colorectal cancer and hepatocellular carcinoma cells, by blocking the activation of the epidermal growth factor receptor (EGFR) family of RTKs. EGCG inhibits the activation of insulin-like growth factor-1 receptor (IGF-1R) and VEGFR2, the other members of the RTK family, and this effect is also associated with the anticancer and chemopreventive properties of this agent. EGCG suppresses the activation of EGFR in part by altering membrane lipid organization and causing the subsequent inhibition of the dimerization and activation of this receptor. Preliminary trials have shown that GTCs successfully prevent the development and progression of precancerous lesions, such as colorectal adenomas, without causing severe adverse effects. The present report reviews evidence indicating that GTCs exert anticancer and chemopreventive effects by inhibiting the activation of specific RTKs, especially EGFR, IGF-1R, and VEGFR2, and concludes that targeting RTKs and their related signaling pathways by using tea catechins could be a promising strategy for the prevention of human cancers.     

Investigation of laser consolidation process for metal powder by two-color pyrometer and high-speed video camera

This paper deals with the measurement of surface temperature on metal powder during the laser consolidation process with two-color pyrometer. Additionally, the aspect of selective laser sintering (SLS) and selective laser melting (SLM) of metal powder is visualized with high speed video camera. As a result, the surface temperature during the laser irradiation was ranged 1520–1810 °C and the consolidation phenomena was classified according to the melting point of metal powder. The metal powder at the heating process cohered intermittently to the melt pool although the laser beam was continuously irradiated to the powder surface.     

Resistance to wear and cavitation erosion of bearing alloys

Sliding wear and vibratory cavitation erosion tests in paraffin oil were carried out on bearing alloys, i.e. tin-based and lead-based white metals, Cu-Pb alloy and leaded bronze. In lubricated wear under mild conditions the surface is worn smooth and a slight difference exists between the wear resistances of the four alloys. In cavitation erosion an eroded surface which is much rougher than the worn surface is formed. Cavitation erosion is affected strongly by the composition and crystal structure of the alloy and thus the erosion resistances of the four alloys differ greatly, the ranking of resistance being lead-based white metal < Cu-Pb alloy < tin-based white metal < leaded bronze. The surface damage, which is caused by the joint action of cavitation erosion and wear, was also investigated by rubbing the eroded surfaces which had been exposed to cavitation erosion for various times. This damage becomes larger with increasing cavitation damage. The resistance to this damage differs much more in the four alloys tested and tends to correlate with the results of the erosion tests rather than those of the wear tests. Therefore, it is clear that the cavitation erosion resistance should be considered in the selection of bearing materials.