529 research outputs found

    Conformal invariance and its breaking in a stochastic model of a fluctuating interface

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    Using Monte-Carlo simulations on large lattices, we study the effects of changing the parameter uu (the ratio of the adsorption and desorption rates) of the raise and peel model. This is a nonlocal stochastic model of a fluctuating interface. We show that for 0<u<10<u<1 the system is massive, for u=1u=1 it is massless and conformal invariant. For u>1u>1 the conformal invariance is broken. The system is in a scale invariant but not conformal invariant phase. As far as we know it is the first example of a system which shows such a behavior. Moreover in the broken phase, the critical exponents vary continuously with the parameter uu. This stays true also for the critical exponent τ\tau which characterizes the probability distribution function of avalanches (the critical exponent DD staying unchanged).Comment: 22 pages and 20 figure

    Increased oxidative stress associated with the severity of the liver disease in various forms of hepatitis B virus infection

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    BACKGROUND: Oxidative stress can be defined as an increase in oxidants and/or a decrease in antioxidant capacity. There is limited information about the oxidative status in subjects with hepatitis B virus infection. We aimed to evaluate the oxidative status in patients with various clinical forms of chronic hepatitis B infection. METHODS: Seventy-six patients with hepatitis B virus infection, in whom 33 with chronic hepatitis, 31 inactive carriers and 12 with cirrhosis, and 16 healthy subjects were enrolled. Total antioxidant response and total peroxide level measurement, and calculation of oxidative stress index were performed in all participants. RESULTS: Total antioxidant response was significantly lower in cirrhotics than inactive HbsAg carriers and controls (p = 0.008 and p = 0.008, respectively). Total peroxide level and oxidative stress index was significantly higher in cirrhotic (p < 0.001, both) and chronic hepatitis B subjects (p < 0.001, both) than inactive HbsAg carriers and controls. Total antioxidant response was comparable in chronic hepatitis B subjects, inactive HbsAg carriers and controls (both, p > 0.05/6). Total peroxide level and oxidative stress index were also comparable in inactive HBsAg carriers and controls (both, p > 0.05/6). Serum alanine amino transferase level was positively correlated with total peroxide level and oxidative stress index only in chronic hepatitis B subjects (p = 0.002, r = 0.519 and p = 0.008, r = 0.453, respectively). CONCLUSION: Oxidative stress occurs secondarily to increased total lipid peroxidation and inadequate total antioxidant response and is related to severity of the disease and replication status of virus in hepatitis B infection

    Dynamic thiol/disulphide homeostasis before and after radical prostatectomy in patients with prostate cancer

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    Thiol groups are important anti-oxidants and essential molecules protecting organism against the harmful effects of reactive oxygen species (ROS). The aim of our study is to evaluate thiol–disulphide homeostasis with a novel recent automated method in patients with localized prostate cancer (PC) before and six months after radical prostatectomy (RP). 18 patients with PC and 17 healthy control subjects were enrolled into the study. Blood samples were collected from the controls subjects and patients before and six months after RP. Thiol–disulphide homeostasis was determined using a recently developed novel method. Prostate-specific antigen (PSA), albumin, total protein, total thiol, native thiol, disulphide and total antioxidant status (TAS) were measured and compared between the groups. Native thiol, total thiol and TAS levels were significantly higher in the control group than the patients before RP (p &lt;.001). There was a non-significant increase in the native thiol, total thiol and TAS levels in the patients six months after RP in comparison to the levels before RP (p values.3,.3 and.09, respectively). We found a significant negative correlation between PSA and thiol levels. Our study demonstrated that the decreased thiol and TAS levels weakened anti-oxidant defence mechanism in the patients with PC as indicated. Increased oxidative stress in prostate cancer patients may cause metabolic disturbance and have a role in the aetiopathogenesis of prostate cancer

    Migrant mothers’ creative interventions into racialized citizenship

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    Racialized migrant mothers are often cast as marginal to theoretical and political debates of citizenship, yet by taking seriously the contributions to cultural and caring citizenship they make, we challenge the racialized boundaries of citizenship. Drawing on theories of enacting citizenship, that is, challenging hegemonic narratives of who can legitimately claim to contribute to citizenship, we explore migrant women’s mothering through participatory theatre methods. Through analysis of participatory action research (PAR) with migrant mothers in London, we emphasize the significance of embodied and affective meanings for challenging racialized citizenship. The theatre methods allow participants to develop collective subjugated knowledges challenging racialized, gendered and classed stratifications of rights, burdens and privileges of caring citizenship. This draws attention to the important role of creativity of the self as an aspect of both cultural and care work for understanding racialized migrant mothers’ citizenship

    Oxidative stress in hepatitis C infected end-stage renal disease subjects

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    BACKGROUND: Both uremia and hepatitis C infection is associated with increased oxidative stress. In the present study, we aimed to find out whether hepatitis C infection has any impact on oxidative stress in hemodialysis subjects. METHODS: Sixteen hepatitis C (+) hemodialysis subjects, 24 hepatitis C negative hemodialysis subjects and 24 healthy subjects were included. Total antioxidant capacity, total peroxide level and oxidative stress index were determined in all subjects. RESULTS: Total antioxidant capacity was significantly higher in controls than hemodialysis subjects with or without hepatitis C infection (all p < 0.05/3), while total peroxide level and oxidative stress index were significantly lower (all p < 0.05/3). Hepatitis C (-) hemodialysis subjects had higher total antioxidant capacity compared to hepatitis C (+) hemodialysis subjects (all p < 0.05/3). Total peroxide level and oxidative stress index was comparable between hemodialysis subjects with or without hepatitis C infection (p > 0.05/3). CONCLUSION: Oxidative stress is increased in both hepatitis C (+) and hepatitis C (-) hemodialysis subjects. However, hepatitis C infection seems to not cause any additional increase in oxidative stress in hemodialysis subjects and it may be partly due to protective effect of dialysis treatment on hepatitis C infection

    Measurement of the total antioxidant response using a novel automated method in subjects with nonalcoholic steatohepatitis

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    BACKGROUND: Oxidative stress, an increase in oxidants and/or a decrease in antioxidant capacity, is one of the potential biochemical mechanisms involved in the pathogenesis of nonalcoholic steatohepatitis. We aimed to investigate the total antioxidant response using a novel automated method in nonalcoholic steatohepatitis subjects. As a reciprocal measure, we also aimed to determine total peroxide level in the same plasma samples. METHODS: Twenty-two subjects with biopsy proven nonalcoholic steatohepatitis and 22 healthy controls were enrolled. Total antioxidant response and total peroxide level measurements were done in all participants. The ratio percentage of total peroxide level to total antioxidant response was regarded as oxidative stress index. RESULTS: Total antioxidant response of subjects with nonalcoholic steatohepatitis was significantly lower than controls (p < 0.05), while mean total peroxide level and mean oxidative stress index were higher (all p < 0.05). In subjects with nonalcoholic steatohepatitis, fibrosis score was significantly correlated with total peroxide level, total antioxidant response and oxidative stress index (p < 0.05, r = 0.607; p < 0.05, r = -0.506; p < 0.05, r = 0.728, respectively). However, no correlation was observed between necroimflamatory grade and those oxidative status parameters (all p > 0.05). CONCLUSION: Nonalcoholic steatohepatitis is associated with increased oxidant capacity, especially in the presence of liver fibrosis. The novel automated assay is a reliable and easily applicable method for total plasma antioxidant response measurement in nonalcoholic steatohepatitis

    Migration, Racism and the Hostile Environment: Making the Case for the Social Sciences

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    Cite as: Social Scientists Against the Hostile Environment (SSAHE)(2020). Migration, racism and the hostile environment : Making the case for the social sciences. London. https://acssmigration.wordpress.com/report/

    Measurement of tibial nerve excursion during ankle joint dorsiflexion in a weight-bearing position with ultrasound imaging

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    The ability of peripheral nerves to stretch and slide is thought to be of paramount importance to maintain ideal neural function. Excursion in peripheral nerves such as the tibial can be measured by analysis of ultrasound images. The aim of this study was to assess the degree of longitudinal tibial nerve excursion as the ankle moved from plantar flexion to dorsiflexion in a standardised weight-bearing position. The reliability of ultrasound imaging to measure tibial nerve excursion was also quantified

    Lead content and isotopic composition in submound and recent soils of the Volga upland

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    Literature data on the historical reconstructions of the atmospheric lead deposition in Europe and the isotopic composition of the ores that are potential sources of the anthropogenic lead in the atmospheric deposition in the lower Volga steppes during different time periods have been compiled. The effect of the increasing anthropogenic lead deposition recorded since the Bronze Age on the level of soil contamination has been investigated. For the first time paleosol buried under a burial mound of the Bronze Age has been used as a reference point to assess of the current contamination level. The contents and isotopic compositions of the mobile and total lead have been determined in submound paleosols of different ages and their recent remote and roadside analogues. An increase in the content and fraction of the mobile lead and a shift of its isotopic composition toward less radiogenic values (typical for lead from the recent anthropogenic sources) has been revealed when going from a Bronze-Age paleosol to a recent soil. In the Bronze-Age soil, the isotopic composition of the mobile lead is inherited from the parent rock to a greater extent than in the modern soils, where the lead is enriched with the less radiogenic component. The effect of the anthropogenic component is traced in the analysis of the mobile lead, but it is barely visible for the total lead. An exception is provided by the recent roadside soils characterized by increased contents and the significantly less radiogenic isotopic composition of the mobile and total lead
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