714 research outputs found
Redox chemistry of iron in fog and stratus clouds
The redox chemistry of Fe in fog and cloudwater has been investigated at coastal and inland locations in the Los Angeles basin, in Bakersfield California, and in Delaware Bay. Samples were collected and analyzed for Fe (Fe(II)), Fe(III), total(Fe), sulfur (S(IV), S(VI)), organic ligands (formate, acetate, oxalate), total organic carbon (TOC), pH, major cations (sodium, calcium, magnesium, potassium, ammonium), chloride, sulfate, nitrate, peroxides, and aldehydes (HCHO); the amount of sunlight was also measured. The ratio Fe(II)/Fe(total) varied between 0.02 and 0.55. The concentration of Fe(II) varied between 0.1 and 5 micromole, and the concentration of total Fe varied between 2 and 27 micromole. The atmospheric redox cycle of Fe involves both dissolved and aerosol surface species and appears to be related to the presence of organic compounds which act as electron donors for the reduction of Fe(III). Fe(III) reduction is enhanced by light but significant Fe(II) levels were observed in the dark. We suggest that reduction of Fe(III) species by organic electron donors may be an important pathway that affects the speciation of Fe in both urban and rural atmospheres. It is possible that reactions involving Fe and organic compounds might be an important source of carboxylic acids in the troposphere
Migrant mothers’ creative interventions into racialized citizenship
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
Measurement of tibial nerve excursion during ankle joint dorsiflexion in a weight-bearing position with ultrasound imaging
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
Oxidative stress in hepatitis C infected end-stage renal disease subjects
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
Migration, Racism and the Hostile Environment: Making the Case for the Social Sciences
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/
The social reproductive worlds of migrants
The articles in this special issue contribute new insights to a growing body of scholarship on the risks and opportunities migration presents for migrant families’ social reproduction, variously understood as the physical and social/cultural processes entailed in reproducing people, and the strategies migrants develop to navigate those risks and opportunities. Informed by the notion of ‘care circulation’ (Baldassar & Merla, 2014) collectively the articles capture a range of migration flows within and between the Global South and Global North, involving low- and high-skilled migrants, with social reproductive responsibilities spanning both ends of the life course, and situated in local/proximate, as well as distant/transnational, contexts
Perceptions of employability among London's low-paid: 'self-determination' or ethnicity?
We investigate how ethnicity, gender and other characteristics affect low-paid workers’ perceptions of their employability in London’s labour market, examining ‘self-determination’, ethnic and dual labour market theories. We find that perceptions vary considerably, both between genders and ethnicities and in the extent to which they are ‘justified’ by human capital attributes. Optimism varies between genders and ethnic groups but individuals’ perceptions vary to an even greater extent within genders and ethnic groups. Hence, individual-level ‘self-determination’ explanations of these perceptions appear to have greatest explanatory power though ethnic theories also have utility
Lead content and isotopic composition in submound and recent soils of the Volga upland
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
Visualisation to enhance biomechanical tuning of ankle-foot orthoses (AFOs) in stroke: study protocol for a randomised controlled trial
There are a number of gaps in the evidence base for the use of ankle-foot orthoses for stroke patients. Three dimensional motion analysis offers an ideal method for objectively obtaining biomechanical gait data from stroke patients, however there are a number of major barriers to its use in routine clinical practice. One significant problem is the way in which the biomechanical data generated by these systems is presented. Through the careful design of bespoke biomechanical visualisation software it may be possible to present such data in novel ways to improve clinical decision making, track progress and increase patient understanding in the context of ankle-foot orthosis tuning
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