Spatiotemporal evolutions of radial electric field and turbulence are measured simultaneously in the H-mode transition, which is a prototypical example of turbulence structure formation in ...high-temperature plasmas. In the dynamical phase where transport barrier is established abruptly, the time-space-frequency-resolved turbulent particle flux is obtained. Here we report the validation of the mechanism of transport barrier formation quantitatively. It is found that the particle flux is suppressed predominantly by reducing density fluctuation amplitude and cross phase between density fluctuation and potential fluctuation. Both radial electric field shear and curvature are responsible for the amplitude suppression as was predicted by theory. Turbulence amplitude reduction immediately responds to the growth of the radial electric field non-uniformity and saturates, while cross phase continuously approaches zero.
The prevalence of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) is increasing with the growing epidemics of obesity and diabetes. NAFLD encompasses a ...clinicopathologic spectrum of disease ranging from isolated hepatic steatosis to NASH, which is a more aggressive form of fatty liver disease, to cirrhosis and, finally, hepatocellular carcinoma (HCC). The exact mechanism behind the development of HCC in NASH remains unclear; however, it has been established that hepatic steatosis is the important risk factor in the development of HCC. Metformin has recently drawn attention because of its potential antitumor effect. Here, we investigated the effects of metformin on high-fat diet (HFD)-induced liver tumorigenesis, using a mouse model of NASH and liver tumor. Metformin prevented long-term HFD-induced liver tumorigenesis in C57Bl/6 mice. Of note, metformin failed to protect against liver tumorigenesis in mice that had already begun to develop NAFLD. Metformin improved short-term HFD-induced fat accumulation in the liver, associated with the suppression of adipose tissue inflammation. Collectively, these results suggest that metformin may prevent liver tumorigenesis via suppression of liver fat accumulation in the early stage, before the onset of NAFLD, which seems to be associated with a delay in the development of inflammation of the adipose tissue.
Turbulence and its structure formation are universal in neutral fluids and in plasmas. Turbulence annihilates global structures but can organize flows and eddies. The mutual-interactions between flow ...and the eddy give basic insights into the understanding of non-equilibrium and nonlinear interaction by turbulence. In fusion plasma, clarifying structure formation by Drift-wave turbulence, driven by density gradients in magnetized plasma, is an important issue. Here, a new mutual-interaction among eddy, drift wave and flow in magnetized plasma is discovered. A two-dimensional solitary eddy, which is a perturbation with circumnavigating motion localized radially and azimuthally, is transiently organized in a drift wave - zonal flow (azimuthally symmetric band-like shear flows) system. The excitation of the eddy is synchronized with zonal perturbation. The organization of the eddy has substantial impact on the acceleration of zonal flow.
The synchronization of geodesic acoustic modes (GAMs) and magnetic fluctuations is identified in the edge plasmas of the HL-2A tokamak. Mesoscale electric fluctuations (MSEFs) having components of a ...dominant GAM, and m/n=6/2 potential fluctuations are found at the same frequency as that of the magnetic fluctuations of m/n=6/2 (m and n are poloidal and toroidal mode numbers, respectively). The temporal evolutions of the MSEFs and the magnetic fluctuations clearly show the frequency entrainment and the phase lock between the GAM and the m/n=6/2 magnetic fluctuations. The results indicate that GAMs and magnetic fluctuations can transfer energy through nonlinear synchronization. Such nonlinear synchronization may also contribute to low-frequency zonal flow formation, reduction of turbulence level, and thus confinement regime transitions.
Purpose
Incisional hernia is a major complication after stoma closure and can cause uncomfortable symptoms. In this study, we evaluated the risk factors for hernia formation with the aim of reducing ...the incidence of incisional hernia.
Methods
A total of 134 oncology patients underwent closure of a temporary loop ileostomy between May 2004 and December 2013. The incidence of incisional hernia was determined by routine follow-up computed tomography scanning every 6 months. The relationships between patients’ characteristics, including age, sex, obesity, diabetes mellitus, surgical site infection, chronic obstructive pulmonary disease, hypertension, hypoalbuminemia, smoking, and presence of a midline hernia and the occurrence of incisional hernia were retrospectively evaluated.
Results
The median follow-up time was 47 months (range 8–130). Hernias occurred in 23.9% of patients (32/134). The median time to detection of hernias was 8 months (range 2–39). The Chi-squared test revealed significant differences in obesity (
P
= 0.0003), hypertension (
P
= 0.0057), and incisional hernia history (
P
= 0.0000) between patients with and without incisional hernia. Multivariable analysis and univariate analysis revealed that hypertension and the presence of midline incisional hernia were risk factors for incisional hernia.
Conclusions
Hypertension and the presence of a midline incisional hernia were the major risk factors for incisional hernia after loop ileostomy closure. These risk factors can be addressed before planning surgery.
A Pt-deposited carbon nanotube (CNT) shows higher performance than a commercial Pt-deposited carbon black (CB) with reducing 60% Pt load per electrode area in polymer electrolyte fuel cells (PEFCs) ...below 500
mA/cm
2. K
2PtCl
4 and H
2PtCl
6·6(H
2O) are used for the Pt deposition onto multi-walled CNTs (MWCNTs), which are produced by the catalytic decomposition of hydrocarbons. The electric power densities produced using the Pt/CNT electrodes are greater than that of the Pt/CB by a factor of two to four on the basis of the Pt load per power. CNTs are thus found to be a good support of Pt particles for PEFC electrodes. TEM images show 2–4-nm Pt nanoparticles dispersed on the CNT surfaces. These high performances are considered to be due to the efficient formation of the triple-phase boundaries of gas–electrode–electrolyte. The mechanisms of Pt deposition are discussed for these Pt-deposited CNTs.
No effective drugs have been developed to date to prevent or treat non-alcoholic fatty liver disease (NAFLD), although diet modification and exercise to improve obesity have been attempted. ...Therefore, development of a novel drug/strategy to treat NAFLD is urgently needed. In the present study, a novel concept is proposed for the treatment of NAFLD.
Fisher 344 male rats were given a choline-deficient, l-amino acid-defined (CDAA) diet or a high-fat high-calorie (HF/HC) diet with or without the antiplatelet agents, aspirin, ticlopidine or cilostazol for 16 weeks. Liver steatosis, inflammation and fibrosis, and the possible mechanisms involved were investigated.
All three antiplatelet drugs, namely aspirin, ticlopidine and cilostazol, significantly attenuated liver steatosis, inflammation and fibrosis in the CDAA diet group. Of the three agents, cilostazol was the most effective, and the drug also suppressed HF/HC diet-induced liver steatosis. Cilostazol appeared to exert its beneficial effect against NAFLD by suppressing mitogen-activated protein kinase activation induced by oxidative stress and platelet-derived growth factor via intercepting signal transduction from Akt to c-Raf.
Antiplatelet agents, especially cilostazol, offer the promise of becoming key agents for the treatment of NAFLD.
Background: Fish is one of the most frequent causes of immunoglobulin E (IgE)‐mediated food allergy. Although the fish dark muscle is often ingested with the white muscle, no information about its ...allergenicity and allergens is available.
Methods: Heated extracts were prepared from both white and dark muscles of five species of fish and examined for reactivity with IgE in fish‐allergic patients by enzyme‐linked immunosorbent assay (ELISA) and for allergens by immunoblotting. Cloning of cDNAs encoding parvalbumins was performed by rapid amplification cDNA ends. Parvalbumin contents in both white and dark muscles were determined by ELISA using antiserum against mackerel parvalbumin.
Results: Patient sera were less reactive to the heated extract from the dark muscle than to that from the white muscle. A prominent IgE‐reactive protein of 12 kDa, which was detected in both white and dark muscles, was identified as parvalbumin. Molecular cloning experiments revealed that the same parvalbumin molecule is contained in both white and dark muscles of either horse mackerel or Pacific mackerel. Parvalbumin contents were four to eight times lower in the dark muscle than in the white muscle.
Conclusions: The fish dark muscle is less allergenic than the white muscle, because the same allergen molecule (parvalbumin) is contained at much lower levels in the dark muscle than in the white muscle. Thus, the dark muscle is less implicated in fish allergy than the white muscle.
Aims/hypothesis
Epidemiological studies have revealed that obesity and diabetes mellitus are independent risk factors for the development of non-alcoholic steatohepatitis (NASH) and hepatocellular ...carcinoma. However, the debate continues on whether insulin resistance as such is directly associated with NASH and liver tumourigenesis. Here, we investigated the incidence of NASH and liver tumourigenesis in
Irs1
−/−
mice subjected to a long-term high-fat (HF) diet. Our hypothesis was that hepatic steatosis, rather than insulin resistance may be related to the pathophysiology of these conditions.
Methods
Mice (8 weeks old, C57Bl/6J) were given free access to standard chow (SC) or an HF diet. The development of NASH and liver tumourigenesis was evaluated after mice had been on the above-mentioned diets for 60 weeks. Similarly,
Irs1
−/−
mice were also subjected to an HF diet for 60 weeks.
Results
Long-term HF diet loading, which causes obesity and insulin resistance, was sufficient to induce NASH and liver tumourigenesis in the C57Bl/6J mice. Obesity and insulin resistance were reduced by switching mice from the HF diet to SC, which also protected these mice against the development of NASH and liver tumourigenesis. However, compared with wild-type mice fed the HF diet,
Irs1
−/−
mice fed the HF diet were dramatically protected against NASH and liver tumourigenesis despite the presence of severe insulin resistance and marked postprandial hyperglycaemia.
Conclusions/interpretation
IRS-1 inhibition might protect against HF diet-induced NASH and liver tumourigenesis, despite the presence of insulin resistance.
We investigate spatial structures of turbulence and turbulent transport modulated by the geodesic acoustic mode (GAM), from which the excitation mechanism of the GAM is discussed. The GAM is found to ...be predominantly excited through a localized Reynolds stress force, rather than the dynamic shearing force. The evaluated growth rate is larger than the linear damping coefficients and is on the same order of magnitude as the effective growth rate evaluated from time evolution in the GAM kinetic energy.
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