783 resultados para Canham, Donald


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Phytoplankton biomass and rate of production were measured along a transect from 57.54 degreesN to 37.01 degreesN in the northeast Atlantic during July 1996 and at a series of stations over a 7-day period at 37 degreesN 20 degreesW. Surface nutrient concentrations ranged from 4 mu mol l(-1) NO3-, and 0.35 mu mol l(-1) PO43- at 57.54 degreesN to <10 nmol l(-1) NO3- and similar to 10 nmol l(-1) PO43- at 37.01 degreesN. The greatest phytoplankton biomass and production were measured in the vicinity of a frontal system at 50 degreesN, and there was a general decline in total phytoplankton biomass and production to the south of the transect. Production was measured in three size fractions. At the station with the highest chlorophyll concentrations (50.34 degreesN), phytoplankton cells larger than 5 mum dominated the assemblage, accounting for 72% of the chlorophyll concentration (22.9 mg m(-2)) and 51% of primary production (54.1 mmol Cm-2 d(-1)), but picophytoplankton production was also high (43%). At 57 degreesN, carbon fixation by the > 5 mum fraction accounted for 75% of the daily production of 60.75 mmol Cm-2 d(-1). At 37 degreesN, picophytoplankton was the dominant group, accounting for similar to 58% (10 mg m(-2)) of chlorophyll and similar to 64% (46 mmol Cm-2 d(-1)), of primary production. Nitrate, ammonium and phosphate uptake rates also were determined. Although high nitrate uptake rates were measured in the surface water at similar to 50 degreesN, the greatest uptake rates of both depth-integrated nitrate and ammonium were at the south of the transect. At 37 degreesN, a deep euphotic zone was present and light penetrated through the nitracline; total nitrate uptake was enhanced because of assimilation at the base of the euphotic zone. As a consequence, high values of depth-integrated f-ratio were measured in the oligotrophic waters at the south of the transect. Phosphate was predominantly incorporated into the picoplankton fraction, which included heterotrophic and autotrophic components, at all stations and a significant proportion of phosphate uptake occurred in the dark. The C:N:P assimilation ratios were variable throughout the region; phosphate uptake was generally greater than would be expected if nutrient assimilation were in proportion to the Redfield ratio. (C) 2001 Elsevier Science Ltd. All rights reserved.

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“Simbiosis”, aparecido originalmente en 1956, constituye la instancia inicial de la serie de cuentos policiales de Rodolfo Walsh que, extendida hasta 1962, protagonizan Daniel Hernández y el comisario Laurenzi. Pero “Simbiosis” representa, además, un momento de rupturas en la trayectoria de Walsh, rupturas observables a la luz de su obra previa, y que contribuyen a definir la singular posición que el escritor procura adoptar en el campo literario de la época. En la nacionalización del género policial que propone, el cuento a la vez recupera y cuestiona el canon clásico del género, al adoptar motivos de la literatura fantástica cuya operatividad como explicaciones de un delito se asocia a su origen en el saber popular, saber al cual Laurenzi accede como comisario de pueblo. Correlativamente, la equívoca resolución del crimen, debatida entre dos matrices de género, una racional y otra sobrenatural, así como el interrogante sobre la culpabilidad que deja abierto el relato, son resonancias significativas de su contexto histórico, desatendidas aún por la crítica: se trata, en particular, de los debates sobre culpables e inocentes políticos que inició en 1955 el derrocamiento militar del gobierno peronista.

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The acute myeloid leukaemia (AML)14 trial addressed four therapeutic questions in patients predominantly aged over 60 years with AML and High Risk Myelodysplastic Syndrome: (i) Daunorubicin 50 mg/m(2) vs. 35 mg/m(2); (ii) Cytarabine 200 mg/m(2) vs. 400 mg/m(2) in two courses of DA induction; (iii) for part of the trial, patients allocated Daunorubicin 35 mg/m(2) were also randomized to receive, or not, the multidrug resistance modulator PSC-833 in a 1:1:1 randomization; and (iv) a total of three versus four courses of treatment. A total of 1273 patients were recruited. The response rate was 62% (complete remission 54%, complete remission without platelet/neutrophil recovery 8%); 5-year survival was 12%. No benefits were observed in either dose escalation randomization, or from a fourth course of treatment. There was a trend for inferior response in the PSC-833 arm due to deaths in induction. Multivariable analysis identified cytogenetics, presenting white blood count, age and secondary disease as the main predictors of outcome. Although patients with high Pgp expression and function had worse response and survival, this was not an independent prognostic factor, and was not modified by PSC-833. In conclusion, these four interventions have not improved outcomes in older patients. New agents need to be explored and novel trial designs are required to maximise prospects of achieving timely progress.

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Objective: To test the hypothesis that the self-perception of dental and facial attractiveness among patients requiring orthognathic surgery is no different from that of control patients.

Materials and Methods: Happiness with dental and facial appearance was assessed using questionnaires completed by 162 patients who required orthognathic treatment and 157 control subjects. Visual analog scale, binary, and open response data were collected. Analysis was carried out using a general linear model, logistic regression, and chi-square tests.

Results: Orthognathic patients were less happy with their dental appearance than were controls. Class II patients and women had lower happiness scores for their dental appearance. Among orthognathic patients, the "shape" and "prominence" of their teeth were the most frequent causes of concern. Older subjects, women, and orthognathic patients were less happy with their facial appearance. Class III orthognathic patients, older subjects, and women were more likely to have looked at their own face in profile. A greater proportion of Class II subjects than Class III subjects wished to change their appearance.

Conclusions: The hypothesis is rejected. The findings indicate that women and patients requiring orthognathic surgery had lower levels of happiness with their dentofacial appearance. Although Class II patients exhibited the lowest levels of happiness with their dental appearance, there was some evidence that concerns and awareness about their facial profile were more pronounced among the Class III patients.

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Objective: To establish the extent of psychological problems among patients who require orthognathic treatment. Materials and Methods: Five aspects of psychological functioning were assessed for 162 patients who required orthognathic treatment and compared with 157 control subjects.

Results: Analysis of variance did not detect any significant difference in the five psychological scores recorded for the skeletal II, skeletal III, and control groups. The proportion of subjects with one or more psychological measure beyond the normal range was 27% for skeletal II subjects, 25% for skeletal III subjects, and 26% for control subjects. One skeletal II subject (1.5%), three skeletal III subjects (3%), and five control subjects (3%) required referral for psychological counseling.

Conclusions: The orthognathic patients did not differ significantly from the control subjects in their psychological status. © 2010 by The EH Angle Education and Research Foundation, Inc.

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Donald Horowitz's theory of ethnic conflict suggests that a political party operating in a deeply divided society can be effected by a centrifugal pull even when it is not subject to formal electoral competition. This idea can be applied to Northern Ireland's SDLP in the 1970s, when the party faced no credible electoral rival within its primary political constituency. Doing so helps to explain why the SDLP failed in its original objective of mobilizing a cross-community constituency, and instead became what Horowitz terms an “ethnically based party,” representing the interests of only one side of the political divide in Northern Ireland.

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The goal of this study is to identify cues for the cognitive process of attention in ancient Greek art, aiming to find confirmation of its possible use by ancient Greek audiences and artists. Evidence of cues that trigger attention’s psychological dispositions was searched through content analysis of image reproductions of ancient Greek sculpture and fine vase painting from the archaic to the Hellenistic period - ca. 7th -1st cent. BC. Through this analysis, it was possible to observe the presence of cues that trigger orientation to the work of art (i.e. amplification, contrast, emotional salience, simplification, symmetry), of a cue that triggers a disseminate attention to the parts of the work (i.e. distribution of elements) and of cues that activate selective attention to specific elements in the work of art (i.e. contrast of elements, salient color, central positioning of elements, composition regarding the flow of elements and significant objects). Results support the universality of those dispositions, probably connected with basic competencies that are hard-wired in the nervous system and in the cognitive processes.

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This article is a response to an article by Ray Mackay (1996) which constitutes an attack on stylistic analysis in general, and the writings of the above authors and Ron Carter in particular. Mackay's article (in Language and Communication) accuses stylistics of 'scientificness' and claims that its attempt to provide objective analyses of literary texts is futile.1 We suggest that Mackay has misrepresented what stylisticians have said about objectivity, and that his understanding of objectivity, science and the nature of text-interpretative argument is seriously flawed.

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Background
Results of several trials of antioxidant use during pregnancy have not shown a reduction in pre-eclampsia, but the eff ect in women with diabetes is unknown. We aimed to assess whether supplementation with vitamins C and E reduced incidence of pre-eclampsia in women with type 1 diabetes.

Methods
We enrolled women from 25 UK antenatal metabolic clinics in a multicentre randomised placebo-controlled trial. Eligibility criteria were type 1 diabetes preceding pregnancy, presentation between 8 weeks’ and 22 weeks’ gestation, singleton pregnancy, and age 16 years or older. Women were randomly allocated in a 1:1 ratio to receive1000 mg vitamin C and 400 IU vitamin E (a-tocopherol) or matched placebo daily until delivery. The randomisation sequence was stratifi ed by centre with balanced blocks of eight patients. All trial personnel and participants were masked to treatment allocation. The primary endpoint was pre-eclampsia, which we defi ned as gestational hypertension with proteinuria. Analysis was by modifi ed intention to treat. This study is registered, ISRCTN27214045.

Findings
Between April, 2003, and June, 2008, 762 women were randomly allocated to treatment groups (379 vitamin supplementation, 383 placebo). The primary endpoint was assessed for 375 women allocated to receive vitamins, and 374 allocated to placebo. Rates of pre-eclampsia did not differ between vitamin (15%, n=57) and placebo (19%, 70)groups (risk ratio 0·81, 95% CI 0·59–1·12). No adverse maternal or neonatal outcomes were reported.

Interpretation
Supplementation with vitamins C and E did not reduce risk of pre-eclampsia in women with type 1 diabetes. However, the possibility that vitamin supplementation might be benefi cial in women with a low antioxidant status at baseline needs further testing.

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In a meritocratic society it is assumed that the chance of achieving occupational mobility (OM) is not strongly influenced by one's starting position in terms of class or ethnicity. This paper seeks to explain the drivers of the high levels of OM achieved by one ethnically defined group: the Scots. Educational attainment is shown to be particularly important. A second level of interest is the changing role of internal migrants to a global city in the face of increased international skilled immigration. We investigate whether there is any evidence that the OM of internal migrants is being hindered as a result. The evidence points instead to immobile local labour being more disadvantaged occupationally than mobile labour from peripheral regions of the state.

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Something new is happening to reverse the historical trend of skilled Scots moving to London for career progression. The Scottish population of London and the South East is falling and this despite Scots enjoying continued occupational success within the South East labour market. The authors ask why Scots are leaving the UK's main escalator region and then investigate how these migration changes can best be theorised relative to literature on the mobility of the 'new service class'. Building on Fielding's escalator region hypothesis, the authors report on recent research on longer distance flows out of the UK's main escalator region. They advance the critique of the escalator region hypothesis set out by Findlay et al and ask why people would leave a global city offering good opportunities for occupational mobility. Demographic regime change provides only a partial answer. Other explanations can be found in the changing mobilities of the new service class as they engage in what Smith has defined as 'translocal' and 'transnational' urbanism. The authors argue that Scotland's changing relationship with London and the South East may be representative of a wider set of changes in migration linkages between regional economies and global cities.