829 resultados para Early Age Concrete


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Bridge construction responds to the need for environmentally friendly design of motorways and facilitates the passage through sensitive natural areas and the bypassing of urban areas. However, according to numerous research studies, bridge construction presents substantial budget overruns. Therefore, it is necessary early in the planning process for the decision makers to have reliable estimates of the final cost based on previously constructed projects. At the same time, the current European financial crisis reduces the available capital for investments and financial institutions are even less willing to finance transportation infrastructure. Consequently, it is even more necessary today to estimate the budget of high-cost construction projects -such as road bridges- with reasonable accuracy, in order for the state funds to be invested with lower risk and the projects to be designed with the highest possible efficiency. In this paper, a Bill-of-Quantities (BoQ) estimation tool for road bridges is developed in order to support the decisions made at the preliminary planning and design stages of highways. Specifically, a Feed-Forward Artificial Neural Network (ANN) with a hidden layer of 10 neurons is trained to predict the superstructure material quantities (concrete, pre-stressed steel and reinforcing steel) using the width of the deck, the adjusted length of span or cantilever and the type of the bridge as input variables. The training dataset includes actual data from 68 recently constructed concrete motorway bridges in Greece. According to the relevant metrics, the developed model captures very well the complex interrelations in the dataset and demonstrates strong generalisation capability. Furthermore, it outperforms the linear regression models developed for the same dataset. Therefore, the proposed cost estimation model stands as a useful and reliable tool for the construction industry as it enables planners to reach informed decisions for technical and economic planning of concrete bridge projects from their early implementation stages.

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BACKGROUND: Head and neck (H&N) cancers are a heterogeneous group of malignancies, affecting various sites, with different prognoses. The aims of this study are to analyse survival for patients with H&N cancers in relation to tumour location, to assess the change in survival between European countries, and to investigate whether survival improved over time.
METHODS: We analysed about 250,000 H&N cancer cases from 86 cancer registries (CRs). Relative survival (RS) was estimated by sex, age, country and stage. We described survival time trends over 1999-2007, using the period approach. Model based survival estimates of relative excess risks (RERs) of death were also provided by country, after adjusting for sex, age and sub-site.
RESULTS: Five-year RS was the poorest for hypopharynx (25%) and the highest for larynx (59%). Outcome was significantly better in female than in male patients. In Europe, age-standardised 5-year survival remained stable from 1999-2001 to 2005-2007 for laryngeal cancer, while it increased for all the other H&N cancers. Five-year age-standardised RS was low in Eastern countries, 47% for larynx and 28% for all the other H&N cancers combined, and high in Ireland and the United Kingdom (UK), and Northern Europe (62% and 46%). Adjustment for sub-site narrowed the difference between countries. Fifty-four percent of patients was diagnosed at advanced stage (regional or metastatic). Five-year RS for localised cases ranged between 42% (hypopharynx) and 74% (larynx).
CONCLUSIONS: This study shows survival progresses during the study period. However, slightly more than half of patients were diagnosed with regional or metastatic disease at diagnosis. Early diagnosis and timely start of treatment are crucial to reduce the European gap to further improve H&N cancers outcome.

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This study examined the association between moderate drinking at age 16 (adolescence) and alcohol consumption at age 26 (young adulthood), whilst controlling for possible confounding effects at the individual and family level (assessed at birth and age 10). Using the British Cohort Study (BCS70), 6515 respondents provided data on their adolescent alcohol consumption and other behaviours. Of these, 4392 also completed the survey at age 26. Consumption patterns established in adolescence persisted, to a large degree, into early adulthood. Those adolescents who drank moderately in adolescence drank significantly less in adulthood than those adolescents who drank to heavy or hazardous levels. Implications for health promotion strategies and guidance are discussed.

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BACKGROUND: The accuracy and impact on service uptake of early examination after cataract surgery is not known. DESIGN:   Prospective cohort study. PARTICIPANTS: Cataract patients in rural Indonesia. METHODS: Visual acuity was measured preoperatively, 1day, 1-3, 4-6 and >12weeks after surgery, and 6-8months postoperatively at an outreach examination. Acceptance of second-eye surgery and spectacles was evaluated. MAIN OUTCOME MEASURE: Presenting visual acuity in the operated eye. RESULTS: Among 241 subjects (extracapsular surgery 84%), examinations at 1day, 1-3, 4-6 and >12weeks and 6-8months were completed for 100% (241), 90.9% (219), 67.6% (163), 22.0% (53) and 80.0% (193), respectively. Among subjects at the final examination (mean age 65.8±10.6years, 51.8% male), 73.6% had bilateral preoperative presenting visual acuity≤6/60. By 4-6weeks, the proportion with good (≥6/18) or poor (≤6/60) visual acuity did not differ significantly from the final examination. Among 49 persons accepting free second-eye surgery, 69.4% (34) and 16.3% (8) returned to clinic at 4-6 and >12weeks, respectively. Among 131 patients (67.9%) paying US$7 for glasses, 94 (71.8%) and 30 (22.9%) attended 4- to 6- and >12-week examinations, respectively. CONCLUSION: Even with large-incision surgery, early assessment of postoperative vision is representative of final vision, and may help deliver postoperative services to more of those needing them. © 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.

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The Neolithic and Bronze Age transitions were profound cultural shifts catalyzed in parts of Europe by migrations, first of early farmers from the Near East and then Bronze Age herders from the Pontic Steppe. However, a decades-long, unresolved controversy is whether population change or cultural adoption occurred at the Atlantic edge, within the British Isles. We address this issue by using the first whole genome data from prehistoric Irish individuals. A Neolithic woman (3343–3020 cal BC) from a megalithic burial (10.3× coverage) possessed a genome of predominantly Near Eastern origin. She had some hunter–gatherer ancestry but belonged to a population of large effective size, suggesting a substantial influx of early farmers to the island. Three Bronze Age individuals from Rathlin Island (2026–1534 cal BC), including one high coverage (10.5×) genome, showed substantial Steppe genetic heritage indicating that the European population upheavals of the third millennium manifested all of the way from southern Siberia to the western ocean. This turnover invites the possibility of accompanying introduction of Indo-European, perhaps early Celtic, language. Irish Bronze Age haplotypic similarity is strongest within modern Irish, Scottish, and Welsh populations, and several important genetic variants that today show maximal or very high frequencies in Ireland appear at this horizon. These include those coding for lactase persistence, blue eye color, Y chromosome R1b haplotypes, and the hemochromatosis C282Y allele; to our knowledge, the first detection of a known Mendelian disease variant in prehistory. These findings together suggest the establishment of central attributes of the Irish genome 4,000 y ago.

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The Behavioural Inhibition and Behavioural Activation System (BIS/BAS) scales were developed by Carver and White (1994) and comprise four scales which measure individual differences in personality (Gray 1982, 1991). More recent modifications, namely the five-factor model derived from Gray and McNaughton's (2000) revised Reward Sensitivity Theory (RST) suggests that Anxiety and Fear are separable components of inhibition. This study employed exploratory and confirmatory factor analyses on the scales in order to test whether the four or five-factor model was the better fit in a sample of 994 participants aged 11–30 years. Consistent with RST, superior model fit was shown for the five-factor model with all variables correlated. Significant age effects were observed for BIS Fear and BIS Anxiety, with scores peaking in middle and late adolescence respectively. The BAS subscales showed differential effects of age group. Significantly increasing scores from early to mid and from mid to late adolescence were found for Drive, but the effect of age on Fun Seeking and Reward Responsiveness was not significant.



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New techniques based on embedded sensors have been developed for monitoring reinforced concrete structures for assessing their durability, which can be used instead of the conventional non-destructive test techniques. The continuous monitoring of concrete for its durability with various types of sensors allows not only early assessment of the potential durability of structures, but also a prediction of their service life. Effrosyni Tzoura and Muhammed Basheer of University of Leeds, Sreejith Nanukuttan and Danny McPolin of Queen's University Belfast, John McCarter of Heriot-Watt University, Ken Grattan and Tong Sun of City University London and Sudarshan Srinivasan of Mott MacDonald report.

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The aim of this study is to analyse the influence of performance level, age and gender on pacing during a 100-km ultramarathon. Results of a 100-km race incorporating the World Masters Championships were used to identify differences in relative speeds in each 10-km segment between participants finishing in the first, second, third and fourth quartiles of overall positions (Groups 1, 2, 3 and 4, respectively). Similar analyses were performed between the top and bottom 50% of finishers in each age category, as well as within male and female categories. Pacing varied between athletes achieving different absolute performance levels. Group 1 ran at significantly lower relative speeds than all other groups in the first three 10-km segments (all P < 0.01), and significantly higher relative speeds than Group 4 in the 6th and 10th (both P < 0.01), and Group 2 in the 8th (P = 0.04). Group 4 displayed significantly higher relative speeds than Group 2 and 3 in the first three segments (all P < 0.01). Overall strategies remained consistent across age categories, although a similar phenomenon was observed within each category whereby ‘top’ competitors displayed lower relative speeds than ‘bottom’ competitors in the early stages, but higher relative speeds in the later stages. Females showed lower relative starting speeds and higher finishing speeds than males. ‘Top’ and ‘bottom’ finishing males displayed differing strategies, but this was not the case within females. Although pacing remained consistent across age categories, it differed with level of performance within each, possibly suggesting strategies are anchored on direct competitors. Strategy differs between genders and differs depending on performance level achieved in males but not females.

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Sexual dimorphism in adiposity is well described in adults, but the age at which differences first manifest is uncertain. Using a prospective cohort, we describe longitudinal changes in directly measured adiposity and intrahepatocellular lipid (IHCL) in relation to sex in healthy term infants. At median ages of 13 and 63 days, infants underwent quantification of adipose tissue depots by whole-body magnetic resonance imaging and measurement of IHCL by in vivo proton magnetic resonance spectroscopy. Longitudinal data were obtained from 70 infants (40 boys and 30 girls). In the neonatal period girls are more adipose in relation to body size than boys. At follow-up (median age 63 days), girls remained significantly more adipose. The greater relative adiposity that characterises girls is explained by more subcutaneous adipose tissue and this becomes increasingly apparent by follow-up. No significant sex differences were seen in IHCL. Sex-specific differences in infant adipose tissue distribution are in keeping with those described in later life, and suggest that sexual dimorphism in adiposity is established in early infancy.

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Pesticide exposure during brain development could represent an important risk factor for the onset of neurodegenerative diseases. Previous studies investigated the effect of permethrin (PERM) administered at 34 mg/kg, a dose close to the no observable adverse effect level (NOAEL) from post natal day (PND) 6 to PND 21 in rats. Despite the PERM dose did not elicited overt signs of toxicity (i.e. normal body weight gain curve), it was able to induce striatal neurodegeneration (dopamine and Nurr1 reduction, and lipid peroxidation increase). The present study was designed to characterize the cognitive deficits in the current animal model. When during late adulthood PERM treated rats were tested for spatial working memory performances in a T-maze-rewarded alternation task they took longer to choose for the correct arm in comparison to age matched controls. No differences between groups were found in anxiety-like state, locomotor activity, feeding behavior and spatial orientation task. Our findings showing a selective effect of PERM treatment on the T-maze task point to an involvement of frontal cortico-striatal circuitry rather than to a role for the hippocampus. The predominant disturbances concern the dopamine (DA) depletion in the striatum and, the serotonin (5-HT) and noradrenaline (NE) unbalance together with a hypometabolic state in the medial prefrontal cortex area. In the hippocampus, an increase of NE and a decrease of DA were observed in PERM treated rats as compared to controls. The concentration of the most representative marker for pyrethroid exposure (3-phenoxybenzoic acid) measured in the urine of rodents 12 h after the last treatment was 41.50 µ/L and it was completely eliminated after 96 h.

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RESUMO: Auckland tem sido pioneira na implementação de modelos de Intervenção Precoce em Psicose. No entanto, esta organização do serviço não mudou nos últimos 19 anos. Segundo os dados obtidos da utilização do serviço, no período de 1996 -2012 foram atendidos 997 doentes, que tinham um número médio de 89 contactos (IQR: 36-184), com uma duração média de 62 horas de contactos (IQR: 24-136). Estes doentes passaram um número médio de 338 dias (IQR: 93-757) em contacto com o programa. 517 doentes (52%) não necessitaram de internamento no hospital, e os que foram internados, ficaram uma mediana de 124 dias no hospital (IQR: 40-380). Os doentes asiáticos tiveram um aumento de 50% de probabilidade de serem internados no hospital. Este relatório inclui 15 recomendações para orientar as reformas para o serviço e, nomeadamente, delinear a importância de uma visão organizacional e dos seus componentes-chave. As recomendações incluem o reforço da gestão e da liderança numa estrutura de equipe mais integrada, com recursos dedicados a melhorar a consciencialização da comunidade, a educação e deteção precoce, bem como a capacidade de receber referenciações diretas. Os Indicadores Chave de Desempenho devem ser estabelecidos, mas os Exames de Estado Mental em risco, devem ser removidos. Auckland deve manter a faixa etária alvo atual. A duração do serviço deve ser aumentada para um mínimo de três anos, com a opção de aumentá-la para cinco anos. A proporção de gestor de cuidados para os doentes deve ser preconizada em 1:15, enquanto o pessoal de apoio não-clínico deve ser aumentado. Os psiquiatras devem ter uma carga de trabalho de cerca de 80 doentes por equivalente de tempo completo. Um serviço local de prestação de cuidados deve ser desenvolvido com, nomeadamente, intervenções culturais para responder às necessidades da população multicultural de Auckland. A capacidade de investigação deve ser incorporada no Serviço de Intervenção Precoce em Psicoses. Qualquer alteração deverá envolver contacto com todas as partes interessadas, e a Administração Regional de Saúde deve comprometer-se em tempo, recursos humanos e políticos para apoiar e facilitar a mudança do sistema, investindo de forma significativa para melhor servir a comunidade Auckland.----------------------------------- ABSTRACT: Auckland has been pioneering in the adoption of Early Intervention in Psychosis models but the design of the service has not changed in 19 years. In service utilisation data from 997 patients seen from 1996 -2012, patients had a median number of 89 contacts (IQR: 36-184), with a median duration of 62 hours of contact (IQR: 24-136). Patients spent a median number of 338 days (IQR: 93-757) in contact with the program. 517 patients (52%) did not require admission to hospital, and those who did spent a median of 124 days in hospital (IQR: 40-380). Asian patients had a 50% increased chance of being admitted to hospital. This report includes 15 recommendations to guide reforms to the service, including outlining the importance of vision and key components. It recommends strengthened managerial leadership and a more integrated team structure with dedicated resources for improved community awareness, education and early detection as well as the capacity to take direct referrals. Key Performance Indicators (KPIs) should be established but At Risk Mental States should be excluded. Auckland should maintain the current target age range. The duration of service should be increased to a minimum of three years, with the option to extend this to five years. The ratio of care co-ordinator to patients should be capped at 1:15 whilst non-clinical supporting staff should be increased. Psychiatrists should have a caseload of about 80 per FTE. A local Service Delivery framework should be developed, as should cultural interventions to meet the needs of the multicultural population of Auckland. Research capacity should be incorporated into the fabric of Early Intervention in Psychosis Services. Any changes should involve consultation with all stakeholders, and the DHB should commit to investing time, human and political resources to support and facilitate meaningful system change to best serve the Auckland community.

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Cerebral microangiopathy (CMA) has been associated with executive dysfunction and fronto-parietal neural network disruption. Advances in magnetic resonance imaging allow more detailed analyses of gray (e.g., voxel-based morphometry-VBM) and white matter (e.g., diffusion tensor imaging-DTI) than traditional visual rating scales. The current study investigated patients with early CMA and healthy control subjects with all three approaches. Neuropsychological assessment focused on executive functions, the cognitive domain most discussed in CMA. The DTI and age-related white matter changes rating scales revealed convergent results showing widespread white matter changes in early CMA. Correlations were found in frontal and parietal areas exclusively with speeded, but not with speed-corrected executive measures. The VBM analyses showed reduced gray matter in frontal areas. All three approaches confirmed the hypothesized fronto-parietal network disruption in early CMA. Innovative methods (DTI) converged with results from conventional methods (visual rating) while allowing greater spatial and tissue accuracy. They are thus valid additions to the analysis of neural correlates of cognitive dysfunction. We found a clear distinction between speeded and nonspeeded executive measures in relationship to imaging parameters. Cognitive slowing is related to disease severity in early CMA and therefore important for early diagnostics.

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BACKGROUND: The presence of cognitive and structural deficits in euthymic elderly depressed patients remains a matter of debate. Integrative aetiological models assessing concomitantly these parameters as well as markers of psychological vulnerability such as persistent personality traits, are still lacking for this age group. METHODS: Cross-sectional comparisons of 38 elderly remitted patients with early-onset depression (EOD) and 62 healthy controls included detailed neuropsychological assessment, estimates of brain volumes in limbic areas and white matter hyperintensities, as well as evaluation of the Five-Factor personality dimensions. RESULTS: Both cognitive performances and brain volumes were preserved in euthymic EOD patients. No significant group differences were observed in white matter hyperintensity scores between the two groups. In contrast, EOD was associated with significant increase of Neuroticism and decrease of Extraversion facet scores. LIMITATIONS: Results concern the restricted portion of EOD patients without psychiatric and physical comorbidities. Future longitudinal studies are necessary to determine the temporal relationship between the occurrence of depression and personality dimensions. CONCLUSIONS: After remission from acute depressive symptoms, cognitive performances remain intact in elderly patients with EOD. In contrast to previous observations, these patients display neither significant brain volume loss in limbic areas nor increased vascular burden compared to healthy controls. Further clinical investigations on EOD patterns of vulnerability in old age will gain from focusing on psychological features such as personality traits rather than neurocognitive clues.

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In the southwestern part of the Aiguilles Rouges massif (pre-Alpine basement of the Helvetic realm, western Alps), a metavolcanic sequence, newly defined as the ``Greenstone Unit'',is exposed in two NS trending belts of several 100 metres in thickness. It consists of epidote amphibolites, partly epidote and/or calcic amphibole-bearing greenschists, and small amounts of alkali feldspar-bearing greenschists, which underwent low- to medium-grade metamorphism during Visean oblique collision. Metamorphic calcic amphiboles and epidotes show strong chemical zoning, whereas metamorphic plagioclase is exclusively albitic in composition (An 1-3). The SiO2 content of the subalkaline tholeiitic to calc-alkaline suite ranges continuously from 44 wt% to 73 wt%,but andesitic rocks predominate. The majority of samples have chemical compositions close to recent subduction-related lavas; some are even restricted to recent oceanic arcs (extremely low Ta and Nb contents, high La/Nb and Th/Ta ratios). But several basaltic to basalto-andesitic samples resemble continental tholeiites (low Th/Ta, La/Nb ratio). As it is very probable that both lava types are to some extent contemporaneous, it is proposed that the Greenstone Unit represents a former oceanic volcanic are which temporarily underwent extension during which emplacement of continental tholeiite-like rocks occurred. The cause of the extension remains ambiguous. Considering palaeotectonic significance and age of other metavolcanic units in the Aiguilles Rouges massif, the Greenstone Unit most likely formed in the Early Palaeozoic.