29 results
Family-level moderators of daily associations between discrimination and distress among Mexican-origin youth
- Kristin Valentino, Irene J. K. Park, Mario Cruz-Gonzalez, Jenny Zhen-Duan, Lijuan Wang, Tiffany Yip, Kyle Lorenzo, David Dias, Kiara Alvarez, Margarita Alegría
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- Journal:
- Development and Psychopathology , First View
- Published online by Cambridge University Press:
- 08 April 2024, pp. 1-16
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The current study evaluated cultural values and family processes that may moderate associations between daily racial-ethnic discrimination and distress among Mexican-origin youth. Integrating micro-time (daily diary) and macro-time (longitudinal survey) research design features, we examined familism, family cohesion, and ethnic-racial socialization from youth-, mother-, and father- reports as potential buffers of daily associations between youth racial-ethnic discrimination and youth distress (negative affect and anger). The analytic sample, drawn from the Seguimos Avanzando study, included 317 Mexican-origin adolescents (Mage = 13.5 years) and their parents, recruited from the Midwestern United States. Results indicated that youth-reported familism and family cohesion significantly buffered daily associations between youth racial-ethnic discrimination and youth distress. In contrast, parent-reported familism and family cohesion and some aspects of ethnic-racial socialization exacerbated the discrimination to distress link. The implications of these results are discussed to inform efforts supporting the healthy development of Mexican-origin youth and their families.
Adjunctive Therapy of Text4Support for Treatment-Resistant Depression Patients Receiving Repetitive Transcranial Magnetic Stimulation. A Multicenter Randomized Controlled Pilot Trial
- M. K. Adu, R. da Luz Dias, B. Agyapong, M. Flynn, S. Hassan, S. Sridharan, M. K. White, V. Agyapong
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- Journal:
- European Psychiatry / Volume 66 / Issue S1 / March 2023
- Published online by Cambridge University Press:
- 19 July 2023, p. S838
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Introduction
Despite several treatment strategies for treatment-resistant depression (TRD) exist, including the use of repetitive transcranial magnetic stimulation (rTMS), new therapeutic options are being introduced. Text4Support is a form of cognitive behavior therapy that allows patients with depression to receive daily supportive text messages that seek to correct or alter negative thought patterns through positive reinforcement. Text4Support is deemed a useful augmentation treatment strategy for patients with TRD. It is however currently unknown if adding the Text4Support intervention will enhance patients with TRD’s response to rTMS treatments
ObjectivesThis study aims to assess the initial comparative clinical effectiveness of rTMS when used with and without the Text4Support program as an innovative patient-centered intervention for the management of participants diagnosed with TRD.
MethodsThis study is a multicentered prospective, parallel-design, two-arm, rater-blinded randomized controlled pilot trial. In total, 200 participants diagnosed with TRD will be randomized to one of two treatment arms (rTMS alone and rTMS with Text4Support). Participants in each arm will be made to complete evaluation measures at baseline, 1,3, and 6 months. The primary outcome measure will be the mean change to scores on the Hamilton Depression Rating Scale. Patient service utilization data and clinician-rated measures will also be used to gauge patient progress. Patient data will be analyzed with descriptive statistics, repeated measures, and correlational analyses.
ResultsThe result of the study is expected to be available 18 months after the start of recruitment. We hypothesize that participants enrolled in the rTMS plus Text4Support intervention will achieve superior outcomes compared with participants enrolled in the rTMS treatment alone.
ConclusionsThe concomitant application of the combination of these two treatment techniques has not been investigated previously. Therefore, we hope that this project will provide a concrete base of data to evaluate the practical application and efficacy of using a novel combination of these two treatment modalities.
Disclosure of InterestNone Declared
The evaluation of a personalised nutrition and physical activity tool to facilitate lifestyle changes for adults with poor-quality diets
- S.L. Wilson-Barnes, S.A. Lanham-New, L. Gymopoulos, V. Solachidis, K. Dimitopoulos, K. Rouskas, N. Argiriou, D. Tsatsou, J.M. Botana, R. Leoni, N. Merry, E. Lalama, A. Pfeiffer, M. Hassapidou, I. Pagkalos, E. Patra, V. Cornelissen, E. Decorte, S. Balula Dias, Y. Oikonomidis, E. Mantovani, M. Jaksic, B. Brkic, K. Hart
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- Journal:
- Proceedings of the Nutrition Society / Volume 82 / Issue OCE1 / 2023
- Published online by Cambridge University Press:
- 08 March 2023, E42
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A Scoping Review of the Essential Components of Emergency Medical Response Systems for Mass Casualty Incidents
- Agnes Usoro, Amber Mehmood, Sarah Rapaport, Angelica K. Ezeigwe, Adebisi Adeyeye, Oluwafunmilayo Akinlade, Jennifer Dias, Daniel J. Barnett, Edbert B. Hsu, Craig Tower, Junaid Razzak
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- Journal:
- Disaster Medicine and Public Health Preparedness / Volume 17 / 2023
- Published online by Cambridge University Press:
- 04 January 2023, e274
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Objective:
Emergency medical (EM) response systems require extensive coordination, particularly during mass casualty incidents (MCIs). The recognition of preparedness gaps and contextual priorities to MCI response capacity in low- and middle-income countries (LMICs) can be better understood through the components of EM reponse systems. This study aims to delineate essential components and provide a framework for effective emergency medical response to MCIs.
Methods:A scoping review was conducted using 4 databases. Title and abstract screening was followed by full-text review. Thematic analysis was conducted to identify themes pertaining to the essential components and integration of EM response systems.
Results:Of 20,456 screened citations, 181 articles were included in the analysis. Seven major and 40 sub-themes emerged from the content analysis as the essential components and supportive elements of MCI medical response. The essential components of MCI response were integrated into a framework demonstrating interrelated connections between essential and supportive elements.
Conclusions:Definitions of essential components of EM response to MCIs vary considerably. Most literature pertaining to MCI response originates from high income countries with far fewer reports from LMICs. Integration of essential components is needed in different geopolitical and economic contexts to ensure an effective MCI emergency medical response.
The suitability of dietary recommendations suggested By artificial intelligence technology via a novel personalised nutrition mobile application
- K.H. Hart, S. Wilson-Barnes, K. Stefanidis, D. Tsatsou, L. Gymnopoulos, K. Dimitropoulos, K. Rouskas, N. Argiriou, R. Leoni, D. Russell, J. Konstantinova, N. Merry, E. Lalama, A. Pfeiffer, M. Hassapidou, I. Pagkalos, E. Patra, R. Buys, V. Cornelissen, S. Balula Dias, A. Batista, E. Mantovani, B. Brkic, S. Lanham-New
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- Journal:
- Proceedings of the Nutrition Society / Volume 81 / Issue OCE1 / 2022
- Published online by Cambridge University Press:
- 08 February 2022, E37
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Portuguese ABE’s BPSD score (ABS): exploring agreement between ABS items and neuropsychiatric inventory domains
- A.R. Ferreira, C.C. Dias, M.R. Simões, K. Abe, L. Fernandes
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- European Psychiatry / Volume 64 / Issue S1 / April 2021
- Published online by Cambridge University Press:
- 13 August 2021, p. S428
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Introduction
Neuropsychiatric symptoms (NPS) are common, disabling and burdensome core-features of dementia, with important diagnostic and prognostic value. However, their measurement remains challenging. The Neuropsychiatric Inventory (NPI) is the most widely used NPS measure. Nevertheless, it is also time-consuming and impractical in most clinical settings. Therefore, the Abe’s BPSD score (ABS) has been proposed as a brief score to facilitate the NPS assessment.
ObjectivesTo explore the concurrent validity of the Portuguese ABS by comparing the 10 ABS items with the relevant NPI-12 domains.
MethodsA cross-sectional study was conducted with outpatients attending a gerontopsychiatric consultation. Patients were included if they were ≥65 years and had a reliable caregiver. NPS frequency rates (number of patients with a symptom) were estimated with ABS and NPI-12, and an agreement analysis was undertaken by calculating kappa-coefficients (k) and the respective 95% confidence interval [95%CI] between ABS items and relevant NPI-12 domains.
ResultsOverall, 107 patients were included. Kappa-values ranged from 0.277 to 1.000. Higher agreement was recorded for the ABS items eating/toilet problems (k=1.000), day–night reversal (k=0.976[0.925-1.000]) and depressive/gloomy mood (k=0.957[0.899-1.000]), with the NPI-12 appetite/eating abnormalities, night-time behavioural disturbances and dysphoria domains, respectively. The ABS item violent force recorded the lowest agreement (k=0.277[0.104-0.45]) with the NPI-12 agitation/aggression domain.
ConclusionsThis exploratory analysis demonstrates good levels of agreement between most ABS items and relevant NPI-12 domains. Data add to the evidence that both measures capture a comparable broad spectrum of psychopathology, supporting the ABS use in clinical routine. Support: FCT(PD/BD/114555/2016), and National Funds through FCT-within CINTESIS, R&D Unit (ref.UIDB/4255/2020).
Food availability, accessibility and dietary practices during the COVID-19 pandemic: a multi-country survey
- Ali Jafri, Nonsikelelo Mathe, Elom K Aglago, Silvenus O Konyole, Moussa Ouedraogo, Keiron Audain, Urbain Zongo, Amos K Laar, Jeffrey Johnson, Dia Sanou
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- Journal:
- Public Health Nutrition / Volume 24 / Issue 7 / May 2021
- Published online by Cambridge University Press:
- 05 March 2021, pp. 1798-1805
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Objective:
To investigate the perceived effects of the coronavirus disease (COVID-19) pandemic lockdown measures on food availability, accessibility, dietary practices and strategies used by participants to cope with these measures.
Design:We conducted a cross-sectional multi-country online survey between May and July 2020. We used a study-specific questionnaire mainly based on the adaptation of questions to assess food security and coping strategies from the World Food Programme’s ‘Emergency Food Security Assessment’ and ‘The Coping Strategy Index’.
Setting:The questionnaire was hosted online using Google Forms and shared using social media platforms.
Participants:A total of 1075 adult participants from eighty-two countries completed the questionnaire.
Results:As a prelude to COVID-19 lockdowns, 62·7 % of the participants reported to have stockpiled food, mainly cereals (59·5 % of the respondents) and legumes (48·8 %). An increase in the prices of staples, such as cereals and legumes, was widely reported. Price increases have been identified as an obstacle to food acquisition by 32·7 % of participants. Participants reported having lesser variety (50·4 %), quality (30·2 %) and quantity (39·2 %) of foods, with disparities across regions. Vulnerable groups were reported to be facing some struggle to acquire adequate food, especially people with chronic diseases (20·2 %), the elderly (17·3 %) and children (14·5 %). To cope with the situation, participants mostly relied on less preferred foods (49 %), reduced portion sizes (30 %) and/or reduced the number of meals (25·7 %).
Conclusions:The COVID-19 pandemic negatively impacted food accessibility and availability, altered dietary practices and worsened the food insecurity situation, particularly in the most fragile regions.
Reducing the rate of fistula: does a fibrin sealant act as an adjunct in pharyngeal closure? A two-centre experience
- R Roplekar Bance, P Coyle, A Dias, P Kothari, K Shah, J Thaj, F Vaz
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- Journal:
- The Journal of Laryngology & Otology / Volume 134 / Issue 7 / July 2020
- Published online by Cambridge University Press:
- 03 August 2020, pp. 623-625
- Print publication:
- July 2020
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Background
Pharyngocutaneous fistula is a troublesome complication. Recently, synthetic materials such as fibrin sealant have been used as a secondary measure to treat fistula. This work assessed whether the primary use of fibrin sealant can reduce the rate of fistula.
MethodA retrospective review of 50 cases from 2 centres was completed. Tisseel was an adjunct to primary closure in all cases.
ResultsIn the first centre, 3 out of 34 cases developed pharyngocutaneous fistula (fistula rate of 9 per cent). All three were salvage cases. In the second centre, 0 out of 16 cases developed a fistula.
ConclusionThe incidence of pharyngocutaneous fistula post-radiation and post-chemoradiotherapy in laryngectomy cases has been quoted as 23 per cent and 34 per cent respectively. This study represents the first patient series on the use of fibrin sealant as an adjunct in primary closure following laryngectomy. The results are promising, encouraging the use of Tisseel as an adjunct to meticulous closure.
Dietary starch promotes hepatic lipogenesis in barramundi (Lates calcarifer)
- N. M. Wade, L. H. Trenkner, I. Viegas, L. C. Tavares, M. Palma, S. Skiba-Cassy, K. Dias, C. Vachot, B. C. Araújo, N. Bourne, D. Blyth, S. Irvin, B. D. Glencross
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- Journal:
- British Journal of Nutrition / Volume 124 / Issue 4 / 28 August 2020
- Published online by Cambridge University Press:
- 19 March 2020, pp. 363-373
- Print publication:
- 28 August 2020
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Barramundi (Lates calcarifer) are a highly valued aquaculture species, and, as obligate carnivores, they have a demonstrated preference for dietary protein over lipid or starch to fuel energetic growth demands. In order to investigate how carnivorous fish regulate nutritional cues, we examined the metabolic effects of feeding two isoenergetic diets that contained different proportions of digestible protein or starch energy. Fish fed a high proportion of dietary starch energy had a higher proportion of liver SFA, but showed no change in plasma glucose levels, and few changes in the expression of genes regulating key hepatic metabolic pathways. Decreased activation of the mammalian target of rapamycin growth signalling cascade was consistent with decreased growth performance values. The fractional synthetic rate (lipogenesis), measured by TAG 2H-enrichment using 2H NMR, was significantly higher in barramundi fed with the starch diet compared with the protein diet (0·6 (se 0·1) v. 0·4 (se 0·1) % per d, respectively). Hepatic TAG-bound glycerol synthetic rates were much higher than other closely related fish such as sea bass, but were not significantly different (starch, 2·8 (se 0·3) v. protein, 3·4 (se 0·3) % per d), highlighting the role of glycerol as a metabolic intermediary and high TAG-FA cycling in barramundi. Overall, dietary starch significantly increased hepatic TAG through increased lipogenesis. Compared with other fish, barramundi possess a unique mechanism to metabolise dietary carbohydrates and this knowledge may define ways to improve performance of advanced formulated feeds.
Herd-level factors associated with piglet weight at weaning, kilograms of piglets weaned per sow per year and sow feed conversion
- C. R. Pierozan, M. A. Callegari, C. P. Dias, K. L. de Souza, J. Gasa, C. A. da Silva
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To understand the production factors that affect conclusive parameters of sow herd performance can improve the use of the resources and profitability of farm. The objective of this study was to identify associations and quantify the effects of a set of factors related to piglet weight at weaning (PWW), kilograms of piglets weaned per sow per year (kgPWSY) and sow feed conversion (SFC). Data from 150 farms were collected, for a total study population of 135 168 sows, including gilt replacement, breeding (mating), gestation and farrowing/lactation phases. A questionnaire focusing on reproductive performance, management, facilities, feeding, health and biosafety was administered. Multiple linear regression models were used to assess associations among factors with each of the three dependent variables. Increased duration of lactation was positively associated with PWW, kgPWSY and SFC. The increase in the number of live born pigs per litter was positively associated with kgPWSY and with SFC. Farms with higher PWW had farrowing room humidifiers, did not surgically castrate male piglets and used quaternary ammonia compounds for farrowing room disinfection. Farms with higher kgPWSY used lined ceilings in farrowing rooms and winter feeds with higher CP percentages in gestation; they also had more farrowings per sow per year. Sow feed conversion was worse in farms with partly slatted floors during gestation, in farms feeding lactating sows six times a day or ad libitum and farms with a higher sow-handler ratio. This study indicates that farms can increase PWW and kgPWSY and improve the SFC by changing one or more management, biosafety and feeding practices or facilities as well as by focusing on improving several performance parameters, particularly increasing the duration of lactation and the number of live born pigs per litter.
38 - Sustainability Reporting in Africa
- from Part IV - Potential Drivers for Change
- Edited by Beate Sjåfjell, Universitetet i Oslo, Christopher M. Bruner, University of Georgia
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- The Cambridge Handbook of Corporate Law, Corporate Governance and Sustainability
- Published online:
- 25 November 2019
- Print publication:
- 12 December 2019, pp 536-550
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Summary
This chapter explores sustainability reporting regimes in six African countries representing sub-regions of the continent – Egypt, Equatorial Guinea, Kenya, Nigeria, Botswana and South Africa. It reveals that Africa is catching up on sustainability reporting as each jurisdiction is found to have a sustainability reporting regime with an identified regulatory model(s). However, the conflicting nature of sustainability reporting standards calls for a broader reform strategy or policy harmonisation. It thus argues that the African Peer Review Mechanism, Regional Economic Communities, and new African Continental Free Trade Area present opportunities for sustainability reporting policy harmonisation in Africa. It is further argued that African regimes should jettison self-regulatory sustainability reporting models and opt for sanctions-based models or hybrid models combining mandatory and voluntary approaches. It observes, however, that the future of sustainability reporting in Africa lies in integrated reporting with its impact not just on corporate performance but also on strong sustainability.
Emergence of serotype 19A Streptococcus pneumoniae after PCV10 associated with a ST320 in adult population, in Porto Alegre, Brazil
- M.P. Mott, J. Caierão, G.R. Cunha, M.M. Del Maschi, K. Pizzutti, P. d'Azevedo, C.A.G. Dias
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- Journal:
- Epidemiology & Infection / Volume 147 / 2019
- Published online by Cambridge University Press:
- 22 February 2019, e93
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Use of pneumococcal conjugate vaccines has caused emergence of non-vaccine serotypes. No Brazilian data specifically about serotype 19A are available. We aimed to evaluate the frequency of occurrence, susceptibility profile and molecular epidemiology of serotype 19A before and after vaccine introduction in Brazil. Pneumococcal identification was performed by the conventional method. Strain serotype was determined by multiplex polymerase chain reaction (PCR) and/or Quellung reaction. Resistance was determined by Etest® and PCR was performed to determine the presence of macrolide resistance genes, ermB and/or mefA. Pneumococci were typed by Multilocus Sequence Typing. Thirty-eight serotype 19A Streptococcus pneumoniae were recovered, mostly from invasive diseases. Prevalence of serotype 19A increased following vaccination (from 3.5% before vaccination to 8.1% after, p = 0.04196). Non-susceptibility increased to most antimicrobials after vaccine introduction and was associated with clonal complex (CC)320. MLST showed nine different STs, which were grouped in one main CC: CC320 (63.9%). During the post-vaccination era, the frequency of this serotype increased significantly from 1.2% in 2011 to 18.5% in 2014 (p = 0.00001), with a concomitant decrease in the genetic variability: ST320 consistently predominated after vaccine-introduction (61.1%). Overall, our results showed a post-PCV10 increase in the frequency of serotype 19A. This was accompanied by a selection of CC320 and antimicrobial resistance.
Legal Elites and the Shaping of Corporate Law Practice in Brazil: A Historical Study
- Jayanth K. Krishnan, Vitor M. Dias, John E. Pence
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- Journal:
- Law & Social Inquiry / Volume 41 / Issue 2 / Spring 2016
- Published online by Cambridge University Press:
- 27 December 2018, pp. 346-370
- Print publication:
- Spring 2016
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Brazil today has a legal market that allows for foreign lawyers and foreign firms, but existing regulations are restrictive. Foreign lawyers cannot practice domestic law or litigation, nor can Brazilian‐licensed lawyers working for foreign firms or partnering with foreign lawyers. This was not always the case, however. Until 1963, there was little regulation of the legal profession. Beginning in 1913, elite US lawyers traveled to Brazil, with some even becoming prominent domestic practitioners. They partnered with local elite lawyers (who maintained their domestic privileges) and served as key brokers for US businesses seeking market entry. Drawing on the elite theory literature, and on ethnographies, interview data, and over 1,000 pages of rare Portuguese and English archival sources, this study's thesis is that sophisticated US and Brazilian legal elites capitalized on the lack of regulation to advance their financial interests, and in the process transformed Brazil's corporate legal sector.
Contributors
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- By W. Neil Adger, Jeroen Aerts, Armando Apan, Jessica Ayers, Jon Barnett, Juan F. Barrera, Simon P. J. Batterbury, Linda C. Botterill, Sarah Boulter, Edwin Castellanos, Declan Conway, Gustavo Cruz-Bello, W. Priyan, S. Dias, Markus G. Donat, Stephen Dovers, Thomas E. Downing, Hallie Eakin, C. J. Fotheringham, Andrew W. Garcia, Marisa C. Goulden, Daniela Guitart, John Handmer, Katharine Haynes, Sam S. L. Hettiarachchi, Saleemul Huq, Jiang Tong, David John Karoly, Jon E. Keeley, Diane Keogh, David King, Zbigniew W. Kundzewicz, Timothy M. Kusky, Karine Laaidi, Alain Le Tertre, Gregor C. Leckebusch, Matthew Mason, David M. Mills, Helda Morales, Michael J. Mortimore, Colette Mortreux, Karen O’Brien, Jean Palutikof, Mathilde Pascal, Bimal K. Paul, Munshi K. Rahman, William D. Snook, Su Buda, Alexandra D. Syphard, Melanie Thomas, Madeleine C. Thomson, Uwe Ulbrich, Pier Vellinga, George Walker, Joshua Whittaker
- Edited by Sarah Boulter, Griffith University, Queensland, Jean Palutikof, Griffith University, Queensland, David John Karoly, University of Melbourne, Daniela Guitart, Griffith University, Queensland
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- Natural Disasters and Adaptation to Climate Change
- Published online:
- 05 October 2013
- Print publication:
- 14 October 2013, pp ix-xii
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Elemental interdiffusion in W-Ta composites developed for fusion applications
- R. Mateus, M. Dias, V. Livramento, D. Nunes, P.A. Carvalho, K. Hanada, J.B. Correia
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- Journal:
- Microscopy and Microanalysis / Volume 19 / Issue S4 / August 2013
- Published online by Cambridge University Press:
- 06 August 2013, pp. 123-124
- Print publication:
- August 2013
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Tungsten (W) was select for an extensive use in nuclear fusion devices due to its low neutron activation, high melting point and sputtering threshold as well as low hydrogen inventory. Nevertheless, W is brittle at low and moderate temperatures, which results in abnormal thermal stress, component fracture and extra erosion under reactor operation due to inherent thermal cycling events. An attractive way to solve these problems involves the addition of other refractory metals in the W matrix and tantalum (Ta) is a natural candidate. It has a high ductility, toughness and radiation resistance relative to those of W and transmutes to W by high-energy neutron irradiation. Recently, IST proposed the production of W-Ta composite by mechanical synthesis.
The composite should reveal the individual properties of the pristine phases as long as the interdiffusion between the components is significantly avoided during the consolidation/sintering route of the final material. Sintering operations at temperatures higher than 1300ºC lead to significant improvements in the final densification and thermal conductivity of the composites, which is crucial for fusion applications. However, W and Ta interdiffusion can be relevant above 1300ºC, mainly due to diffusion of W into Ta, and the aim of the present work is to control the mechanism.
W-Taf composites presenting 10 and 20 at.% of Ta where produced by alloying W powders and Ta fibres with a planetary ball milling route (MA) and by consolidating the mixture with spark plasma sintering (SPS) in the 1300-1600ºC temperature range. The final densifications remain fairly constant in both composites after sintering at different temperatures (83 to 87%) and the elemental interdiffusion remained low at 1300ºC. Nevertheless, the diffusivity of W in Ta became significant at 1600ºC, leading to the formation of a solid solution zone with a stoichiometry close to W16Ta84. The mechanism was followed by scanning electron and energy-dispersive X-ray spectroscopies (SEM/EDS; Figures 1 and 2, Table 1). Fabrication routes yielding high densifications and low interdiffusion are currently under investigation.
The work has been supported by the Contract of Association between Euratom and IST and by the Fund. Ciência e a Tecnologia contracts PTDC/CTM/100163/2008, Pest-OE/SADG/LA0010/2011 and PEST-OE/CTM-UI0084/2011.
Studies on deuterium retention in W-Ta based materials
- M. Dias, R. Mateus, N. Catarino, V. Livramento, J.B. Correia, P.A. Carvalho, K. Hanada, N. Pinhão, P. Barquinha, E. Alves
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- Journal:
- Microscopy and Microanalysis / Volume 19 / Issue S4 / August 2013
- Published online by Cambridge University Press:
- 06 August 2013, pp. 125-126
- Print publication:
- August 2013
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The high melting point, high sputtering threshold and low tritium inventory rendered W as a potentially suitable material in fusion devices. The major problem associated with presently available tungsten grades as structural materials is its brittleness at lower temperatures. This is further worsened by irradiation embrittlement. A strategy for ductility improvement is producing a composite, with the brittle W matrix being reinforced by short fibres of tantalum. As Ta is more ductile than W it can therefore divert or stop cracks propagating in the W matrix. In the present research Ta short fibres and powder were used as reinforcement component for W by alloying Ta short fibres or powder in a W powder matrix. The composites were subsequently irradiated with deuterium to assess the retention of this hydrogenic species in the materials.
The irradiated composites, with Ta contents of 10 or 20 at%, were produced from pure elemental powders (W-Ta powder composites), and pure W powder and Ta fibre (W-Ta fibre composites) with 100 μm in diameter by low energy ball milling in argon atmosphere. These materials were consolidated via spark plasma sintering (SPS) in the temperature 1200 to 1600 ºC range. Pure W and Ta plates (controls) and W-Ta composites were irradiated with He+ ions (optional pre-implantation step) and D+ ion beams at room temperature with fluences in the 1020-1021 at/m2 range. Blistering and deuterium retention in W and Ta plates and in W-Ta composites were studied with scanning electron microscopy (SEM), X-ray diffraction and thermal desorption analysis. The deuterium concentration was evaluated trough nuclear reaction analysis (NRA) using 0.75 to 2.1 MeV 3He+ beam and the D(3He,p)α reaction.
The investigations showed that deuterium irradiation induced microstructural modifications producing blistering in Ta plates as well as in W-Ta composites (Figure 1). These effects increased substantially in the Ta and W-Ta materials with the He pre-implantation step, while blisters have not been observed in the W plates either for D+ or He+ plus D+ implantation. Higher deuterium retention was observed by thermal desorption for the composites than for the W plates. Moreover the present study revealed that D+ trapping in the composites is dependent on the microstructure with higher retention observed for fibers than for powder.
This work has been performed under the Contract of Association between EURATOM and Instituto Superior Tecnico. Financial support was also received from the Fundação para a Ciência Tecnologia (FCT) grants with references PTDC/CTM/100163/2008, Pest-OE/SADG/LA0010/2011 and PEST-OE/CTM-UI0084/2011. The authors wish to acknowledge Jorge Rocha the implantation in W-Ta samples.
Forward directed ion acceleration in a LWFA with ionization-induced injection
- N. LEMOS, J. L. MARTINS, J. M. DIAS, K. A. MARSH, A. PAK, C. JOSHI
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- Journal:
- Journal of Plasma Physics / Volume 78 / Issue 4 / August 2012
- Published online by Cambridge University Press:
- 10 January 2012, pp. 327-331
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In this work we present an experimental study where energetic ions were produced in an underdense 2.5 × 1019 cm−3 plasma created by a 50 fs Ti:Sapphire laser with 5 TWs of power. The plasma comprises 95% He and 5% N2 gases. Ionization-induced trapping of nitrogen K-shell electrons in the laser-induced wakefield generates an electron beam with a mean energy of 40 MeV and ~1 nC of charge. Some of the helium ions at the wake–vacuum interface are accelerated with a measured minimum ion energy of He1+ ions of 1.2 MeV and He2+ ions of 4 MeV. The physics of the interaction is studied with 2D particle-in-cell simulations. These reveal the formation of an ion filament on the axis of the plasma due to space charge attraction of the wakefield-accelerated high-charge electron bunch. Some of these high-energy electrons escape the plasma to form a sheath at the plasma–vacuum boundary that accelerates some of the ions in the filament in the forward direction. Electrons with energy less than the sheath potential cannot escape and return to the plasma boundary in a vortex-like motion. This in turn produces a time-varying azimuthal magnetic field, which generates a longitudinal electric field at the interface that further accelerates and collimates the ions.
The effect of growth hormone (GH) and insulin-like growth factor-I (IGF-I) on in vitro maturation of equine oocytes
- Gabriel Ribas Pereira, Pedro Luis Lorenzo, Gustavo Ferrer Carneiro, Barry Allen Ball, Paulo Bayard Dias Gonçalves, Lígia Maria Cantarelli Pegoraro, Sylvie Bilodeau-Goeseels, John P. Kastelic, Patrick J. Casey, Irwin K. M. Liu
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The objective of this study was to test the hypothesis that equine growth hormone (eGH), in combination with insulin growth factor-I (IGF-I), influences positively in vitro nuclear and cytoplasmic maturation of equine oocytes. Cumulus–oocyte complexes were recovered from follicles that were < 25 mm in diameter, characterized by morphology and were allocated randomly as follow: (a) control (no additives); (b) 400 ng/ml eGH; (c) 200 ng/ml IGF-I; (d) eGH + IGF-I; and (e) eGH + IGF-I + 400 ng/ml anti-IGF-I antibody. Oocytes were matured for 30 h at 38.5°C in air with 5% CO2 and then stained with 10 μg/ml propidium iodide (PI) to evaluate nuclear status and 10 μg/ml Lens culinaris agglutinin-fluorescein complex (FITC-LCA) to assess cortical granule migration by confocal microscopy. The proportion of immature oocytes that developed to the metaphase II (MII) stage in the eGH + IGF-I group (15 of 45) was greater than in the groups that were treated only with IGF-I (7 of 36, p = 0.03). Oocytes that reached MII in the control group (20 of 56; 35.7%) showed a tendency to be different when compared with eGH + IGF-I group (15 of 45; 33.3%, p = 0.08). The treated group that contained anti-IGF-I (15 of 33; 45.4%) decreased the number of oocytes reaching any stage of development when compared with eGH (47 of 72; 65.3%) and eGH + IGF-I (33 of 45; 73.3%) groups (p = 0.05) when data from MI and MII were combined. We concluded that the addition of eGH to in vitro maturation (IVM) medium influenced the in vitro nuclear and cytoplasmic maturation of equine oocytes. The use of GH and IGF-I in vitro may represent a potential alternative for IVM of equine oocytes.
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. 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Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. 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- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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Geochemical and scintillometric characterization and correlation of amethyst geode-bearing Paraná lavas from the Quaraí and Los Catalanes districts, Brazil and Uruguay
- LÉO A. HARTMANN, WILSON WILDNER, LAUREN C. DUARTE, SANDRO K. DUARTE, JULIANA PERTILLE, KARINE R. ARENA, LAURA C. MARTINS, NORBERTO LESSA DIAS
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- Geological Magazine / Volume 147 / Issue 6 / November 2010
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- 19 July 2010, pp. 954-970
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Geochemical studies of the six lowermost lava flows of the Cretaceous Serra Geral Formation (Paraná volcanic province) in Quaraí (Brazil) and Artigas (Uruguay) were combined with flow-by-flow field studies of structures and scintillometric profiles to establish a consistent regional stratigraphic framework over at least 100 km. This greatly improves exploration capability for amethyst and agate geodes. A basalt, colada Mata Olho (Alegrete facies, Serra Geral Formation), was the first lava to flow over the ancient Botucatu desert in the region, but an andesite, colada Catalán, overstepped this basalt in many places, perhaps palaeohighs. Four basaltic andesites complete the lava stratigraphy in this formation, adding up to 300 m of lavas. The stratigraphic sequence of contrasting lava compositions is 51.0 wt% SiO2 in the first lava, followed by 57.5, 52.5, 56.0, 53.0 and finally 54.5 wt% SiO2. Overall MgO variation is between 2 and 7 wt%. All lavas in the two districts are low-Ti (<2.0 wt% TiO2) of the Gramado type. The characteristic contents of most major and trace elements (124 rock samples analysed) allow the ready identification of each lava. Contrasting rock chemistry also results in strong variation in scintillometric values (270 points measured in the field and nineteen continuous borehole profiles); from bottom to top of the stratigraphy, the cps values are 49±3.2, 123±10.3, 62±4.7, 94±4.6, ~45 and ~85. Colada Catalán has the structure of aa lava, particularly the contorted igneous banding and autobreccias in the upper and lower crusts. In some places, a 2 m thick, silicified sandstone layer lies on top of some coladas, and silicified sandstone forms breccias with volcanic rocks. Geochemistry of the six lavas indicates complex evolution, involving melting of lithospheric mantle, injection into the crust and assimilation of crust followed by fractional crystallization. This study indicates the possibility of world-class deposits of amethyst geodes on the Brazilian side of the border with Uruguay.