875 research outputs found

    Translanguaging as a strategy to boost human learning : an event-related potential (ERP) investigation

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    Bilingual education has witnessed a major shift towards mixing two languages in the classroom. However, adequate methods taking into account the needs of today’s highly multicultural world require scientific testing. Translanguaging is a method of learning in which students produce an output of their learning in a language different to that of instruction. So far, insights into the potential benefits of this method have been exclusively qualitative. The aim of this thesis was to quantify the benefits of translanguaging for new knowledge acquisition. In the main experiment (Chapter 4) I have found neuroscientific evidence for facilitated access to existing semantic representations for items used in learning mediated by translanguaging as compared to control items presented in a monolingual learning context. Participants were tested using a picture-picture priming paradigm after a learning phase involving either English or a code-switch between English and Welsh simultaneous with a switch between reading and speaking. Beyond the expected effect of semantic relatedness on the mean N400 amplitude, well known to index semantic processing effort (Kutas and Hillyard, 1980), a striking main effect of translanguaging on the same N400 was found, suggesting that relevant semantic representations had become selectively more accessible in long-term memory. Moreover, this effect could still be measured 2 to 4 weeks later without participant training. In chapters 5 and 6, I have set out to test the two components of translanguaging separately in order to determine the contribution to the overall effect of code-switching on one hand and comprehension-to-production on another. Chapter 5 focuses on the automaticity of semantic priming and the potential impact of code-switching on the N400 in Welsh-English bilinguals. Chapter 6 focuses on the effects of the comprehension-to-production switch on the N400 in Basque-Spanish bilinguals

    Colloidal gas aphron extraction of bioactive compounds from brazilian pinot noir grape pomace.

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    Residues from the food industry are a problem worldwide. Alternatives have been developed in an attempted to extract compounds from fruit pomace in other to apply those as a natural component in different products. This work has the objective to produce two extracts: (1) ethanolic extract and (2) hot water extract; and characterize the chemical composition of these extracts for future application. In sequence an extraction using surfactants (Colloidal Gas Aphron) was applied in order to obtain a more concentrate and pure extract, in a foam form with better physical properties. The ethanolic extraction was more efficient, obtaining 4 times more bioactive compound (in 100g of pomace: 2670.63 mg Gallic Acid; 65.70 mg anthocyanins and 45,564.78 mmol of Trolox). However the CGA was able to concentrate more the compounds from hot water extract, 61.62% of phenolics compounds were concentrated in the Aphron phase

    ‘They care rudely!’: resourcing and relational health system factors that influence retention in care for people living with HIV in Zambia.

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    Introduction: Despite access to free antiretroviral therapy (ART), many HIV-positive Zambians disengage from HIV care. We sought to understand how Zambian health system ‘hardware’ (tangible components) and ‘software’ (work practices and behaviour) influenced decisions to disengage from care among ‘lost-to-follow-up’ patients traced by a larger study on their current health status. Methods: We purposively selected 12 facilities, from 4 provinces. Indepth interviews were conducted with 69 patients across four categories: engaged in HIV care, disengaged from care, transferred to another facility and next of kin if deceased. We also conducted 24 focus group discussions with 158 lay and professional healthcare workers (HCWs). These data were triangulated against two consecutive days of observation conducted in each facility. We conducted iterative multilevel analysis using inductive and deductive reasoning. Results: Health system ‘hardware’ factors influencing patients’ disengagement included inadequate infrastructure to protect privacy; distance to health facilities which costs patients time and money; and chronic understaffing which increased wait times. Health system ‘software’ factors related to HCWs’ work practices and clinical decisions, including delayed opening times, file mismanagement, drug rationing and inflexibility in visit schedules, increased wait times, number of clinic visits, and frustrated access to care. While patients considered HCWs as ‘mentors’ and trusted sources of information, many also described them as rude, tardy, careless with details and confidentiality, and favouring relatives. Nonetheless, unlike previously reported, many patients preferred ART over alternative treatment (eg, traditional medicine) for its perceived efficacy, cost-free availability and accompanying clinical monitoring. Conclusion: Findings demonstrate the dynamic effect of health system ‘hardware’ and ‘software’ factors on decisions to disengage. Our findings suggest a need for improved: physical resourcing and structuring of HIV services, preservice and inservice HCWs and management training and mentorship programmes to encourage HCWs to provide ‘patient-centered’ care and exercise ‘flexibility’ to meet patients’ varying needs and circumstances

    Rethinking retention: mapping interactions between multiple factors that influence long-term engagement in HIV care

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    Background: Failure to keep people living with HIV engaged in life-long care and treatment has serious implications for individual and population-level health. Nested within a four-province study of HIV care and treatment outcomes, we explored the dynamic role of social and service-related factors influencing retention in HIV care in Zambia. Methods: From a stratified random sample of 31 facilities, eight clinics were selected, one urban and one rural from each province. Across these sites we conducted a total of 69 in-depth interviews, including with patients (including pregnant women) engaged in-care (n = 28), disengaged from care (n = 15), engaged facility transferee (n = 12), and friends/family of deceased patients (n = 14). At the same sites we conducted 24 focus group discussions with a total of 192 lay and professional healthcare workers (HCWs). Two-day observations in each of the eight facilities helped triangulate data on operational context, provider relations and patient-provider interactions. We ordered and analysed data using an adapted version of Ewart's Social Action Theory. Results: Three overarching findings emerged. First, the experience of living with HIV and engaging in HIV care in Zambia is a social, not individual experience, influenced by social and gendered norms and life goals including financial stability, raising family and living stigma-free. Second, patients and their networks act collectively to negotiate and navigate HIV care. Anticipated responses from social network influenced patients' willingness to engage in care, while emotional and material support from those networks influenced individuals' capacity to remain in HIV care. Lastly, health system factors were most influential where they facilitated or undermined peoples' collective approach to health service use. Participants living with HIV reported facilitation of both their initial and continued engagement in care where services involved social networks, such as during couples testing and community outreach. Conversely, service features that were poorly aligned with respondents' social reality (e.g. workplace obligations) hindered long-term engagement. Conclusions: This study moves beyond listing barriers or socio-ecological groupings, to explain how social and health systems interact to produce HIV care outcomes. Our findings challenge the implicit assumption of individual agency underpinning many retention studies to highlight the social nature of illness and healthcare utilization for HIV in Zambia. This understanding of collective action for accessing and remaining in HIV care should underpin future efforts to revise and reform HIV and potentially other chronic service models and systems

    A Method of Specifying the Gravity Wave Spectrum above Convection Based on Latent Heating Properties and Background Wind

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    The spectrum of convectively generated gravity waves is currently not resolved in general circulation models and must be parameterized. Due to the lack of understanding of the connection between convection properties and gravity waves, such parameterizations assume a source spectrum of gravity waves that is not linked to the forcing region. This paper introduces a method of specifying the gravity wave spectrum above convection based on the latent heating properties and background wind in the convective region that can be implemented in general circulation models. This method is based on linear calculations of momentum flux generated by a multifrequency thermal forcing and incorporates the effects of tropospheric mean wind in the convective environment. In the analysis, gravity waves that are generated by both the steady and the oscillatory component of the heating are included. It is shown that an accurate spectrum of convectively generated gravity waves can be deduced from the knowledge of approximate horizontal and vertical scales of the latent heating region, the heating rate, and tropospheric wind profile. 1

    Experimental investigation of mid-infrared laser action from DY3+ doped fluorozirconate fiber

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    Efficient continuous-wave laser operation at 2.982 μm is achieved with a Dy3:fluoride fiber pumped using an inhouse-built 1.1 μm ytterbium (III) fiber laser. The laser output power reached is 554 mW, with a maximum slope efficiency of 18% with respect to the launched pump power. Additionally, the measured spontaneous luminescence within the visible wavelength range, under 1.1 μm pumping, is presented and attributed to excited state absorption (ESA). The influence of the ESA on the laser performance is discussed. The results confirm that high output powers from Dy: fluoride fiber laser pumped at 1.1 μm are possible

    AAC Penhold Canada Prairie Spring Red Wheat

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    AAC Penhold, an awned hard red spring wheat (Triticum aestivum L.) cultivar, yielded significantly more grain than 5700PR while maturing 2 days earlier, and 7.5 cm shorter stature. The seed size was significantly larger than 5700PR and 5701PR, with a test weight significantly heavier than both checks. AAC Penhold expressed resistance to prevalent races of leaf rust and common bunt, and moderate resistance to fusarium head blight and stem rust. AAC Penhold had higher grain and flour protein than the checks and improved Hagberg Falling Number, amylograph viscosity, and water absorption. AAC Penhold is eligible for grades of the market class, Canada Prairie Spring Red wheat

    A Preliminary Assessment of Rotavirus Vaccine Effectiveness in Zambia

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    BACKGROUND: Diarrhea is the third leading cause of child death in Zambia. Up to one-third of diarrhea cases resulting in hospitalization and/or death are caused by vaccine-preventable rotavirus. In January 2012, Zambia initiated a pilot introduction of the Rotarix live, oral rotavirus vaccine in all public health facilities in Lusaka Province. METHODS: Between July 2012 and October 2013, we conducted a case-control study at 6 public sector sites to estimate rotavirus vaccine effectiveness (VE) in age-eligible children presenting with diarrhea. We computed the odds of having received at least 1 dose of Rotarix among children whose stool was positive for rotavirus antigen (cases) and children whose stool was negative (controls). We adjusted the resulting odds ratio (OR) for patient age, calendar month of presentation, and clinical site, and expressed VE as (1 - adjusted OR) × 100. RESULTS: A total of 91 rotavirus-positive cases and 298 rotavirus-negative controls who had under-5 card-confirmed vaccination status and were ≥6 months of age were included in the case-control analysis. Among rotavirus-positive children who were age-eligible to be vaccinated, 20% were hospitalized. Against rotavirus diarrhea of all severity, the adjusted 2-dose VE was 26% (95% confidence interval [CI], -30% to 58%) among children ≥6 months of age. VE against hospitalized children ≥6 months of age was 56% (95% CI, -34% to 86%). CONCLUSIONS: We observed a higher point estimate for VE against increased severity of illness compared with milder disease, but were not powered to detect a low level of VE against milder disease

    Trapping and aerogelation of nanoparticles in negative gravity hydrocarbon flames

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    We report the experimental realization of continuous carbon aerogel production using a flame aerosol reactor by operating it in negative gravity (−g; up-side-down configuration). Buoyancy opposes the fuel and air flow forces in −g, which eliminates convectional outflow of nanoparticles from the flame and traps them in a distinctive non-tipping, flicker-free, cylindrical flame body, where they grow to millimeter-size aerogel particles and gravitationally fall out. Computational fluid dynamics simulations show that a closed-loop recirculation zone is set up in −g flames, which reduces the time to gel for nanoparticles by ≈10[superscript 6] s, compared to positive gravity (upward rising) flames. Our results open up new possibilities of one-step gas-phase synthesis of a wide variety of aerogels on an industrial scale
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