5,420 research outputs found

    The impact of rain water on soil pore networks following irrigation with saline-sodic water

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    The soil pore network is an important factor affecting soil hydraulic conductivity (Ksat). In this study we examine the effect on the soil pore network of a Red Ferrosol caused by irrigation with good quality irrigation water (GQW), as well as saline-sodic water with varying sodium absorption ratios (SAR; 10, 50 and 120) and constant electrical conductivity (EC; 2 dS m-1), followed by application of distilled water (simulating rain water). The Ksat was measured for the different waters before and after applying the rain water to the soil. Soil samples were taken from different depths (1, 4 and 8 cm) for exchangeable cations measurement and the changes in ESP of the soil. Soil horizontal cross-sections were taken from the first 2 cm of the soil cores after drying with acetone and impregnation with polyester resin mixed with green fluorescent dye catalyst and hardener. These sections were polished and visualized under a microscope to investigate the changes in the soil pore network. By increasing the SAR of the water applied from 0.11 (GQW) to SAR 50 and 120, a significant reduction in Ksat was found, alongside a significant increase in the ESP of the soil from 3 to 10 and 11, respectively; this was most evident near the soil surface. After applying rain water, the Ksat reduced significantly approaching 0 mm h-1 where soil was treated with water of SAR 120. Visualisation of the soil pore network of the treated soils following the application of deionised water clearly showed a reduction in soil macroporosity where water quality of SAR ≥10 was applied, even where soils were non-sodic. Where irrigation occurred with good quality, low SAR water, this reduction was not evident

    The Schizotypal Personality Questionnaire for Children (SPQ-C): Factor Structure, Child Abuse, and Family History of Schizotypy

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    There is a relative dearth of research on features of schizotypal personality in children, in part due to lack of instrumentation. This study tests 5 competing models of the factor structure of the self-report Schizotypal Personality Questionnaire for Children (SPQ-C) and examines its relationship with a family history of schizotypal personality disorder (SPD), child abuse, and stability over time. Hypotheses were tested on 454 11- to 12-year-old schoolchildren and their caregivers. Confirmatory factor analyses supported a 3-factor structure of the SPQ-C (cognitive-perceptual, interpersonal, and disorganized). Test-retest stability was relatively robust over 3 months (r = .67), 6 months (r = .64), and 12 months (r = .55), with acceptable internal reliabilities (r = .84 to .91). Regarding construct validity, children with a biological family history of SPD had higher scores on all 3 factors (d =.51). Abused children had higher schizotypy scores (d = .55). A genetic × environment interaction was observed, with schizotypy highest in those with both a family history of schizotypy and also child abuse. Findings are the first in the child schizotypy field to document a gene × environment interaction and the independence of child abuse from confounding genetic influences. Results support the utility of the SPQ-C in future family and clinical studies of schizotypal personality and provide an avenue for much-needed and neglected research into the early antecedents of child schizotypal personality

    Problem behavior and heart rate reactivity in adopted adolescents: Longitudinal and concurrent relations.

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    The present longitudinal study examined resting heart rate and heart rate variability and reactivity to a stressful gambling task in adopted adolescents with aggressive, delinquent, or internalizing behavior problems and adopted adolescents without behavior problems (total N=151). Early-onset delinquent adolescents showed heart rate hyporeactivity to the stress-eliciting gambling task compared to late-onset delinquent adolescents and adolescents without behavior problems. Heart rate, heart rate variability, and reactivity to stress were not related to environmental factors such as early-childhood parental sensitivity, parental socioeconomic status, or adoptee's health status at arrival. We conclude that the distinction between delinquency and aggression and between childhood-onset and adolescence-onset delinquency is important for the study of stress reactivity in adolescents. Copyright © 2008, Society for Research on Adolescence

    Nutritional status of food consumption patterns of young children living in Western Uganda

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    Objectives: The aim of this pilot study was to compare the nutritional status and food consumption patterns of children under five years. Design: Quantitative, exploratory, cross sectional study. Setting: Kabarole district, western Uganda. Kabarole district is a rural district with subsistence farming as the main income. Subjects: Two hundred and five children between 12 and 72 months of age living in AIDS affected homes versus children living in non-AIDS affected homes were examined. Results: Fifty-five percent of all children were stunted and 20.5% were underweight. There was no difference in the prevalence of malnutrition between children living in AIDS affected homes versus non-AIDS affected homes. Only children between 12-35 months suffered from a daily deficit in caloric intake. The older children consumed the basic recommended daily intake (RDI) for protein, fat, iron and vitamin A. Due to frequent disease episodes and limitations in the estimations of individual total energy expenditure, the results are likely underestimations of the children's true nutritional requirements. The type of foods given to children in AIDS affected homes and controls were quite similar. Conclusion: Young children in Kabarole district suffer from severe chronic malnutrition rates, but rates and feeding patterns are not different in AIDS affected versus non AIDS affected homes. The East African Medical Journal Vol. 83 (11) 2006: pp. 619-62

    On the puzzle of Bremsstrahlung as described by coaccelerated observers

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    We consider anew some puzzling aspects of the equivalence of the quantum field theoretical description of Bremsstrahlung from the inertial and accelerated observer's perspectives. More concretely, we focus on the seemingly paradoxical situation that arises when noting that the radiating source is in thermal equilibrium with the thermal state of the quantum field in the wedge in which it is located, and thus its presence does not change there the state of the field, while it clearly does not affect the state of the field on the opposite wedge. How then is the state of the quantum field on the future wedge changed, as it must in order to account for the changed energy momentum tensor there? This and related issues are carefully discussed.Comment: 29 pages, 1 figure; Revtex, minor changes, PACS correcte

    Correction to: The hidden therapist: evidence for a central role of music in psychedelic therapy.

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    The article The hidden therapist: evidence for a central role of music in psychedelic therapy, written by Mendel Kaelen, Bruna Giribaldi, Jordan Raine, Lisa Evans, Christopher Timmerman, Natalie Rodriguez, Leor Roseman, Amanda Feilding, David Nutt, Robin Carhart-Harris, was originally published electronically on the publisher's internet portal

    Estimating the furrow infiltration characteristic from a single advance point

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    Management and control of surface irrigation, in particular furrow irrigation, is limited by spatio-temporal soil infiltration variability as well as the high cost and time associated with collecting intensive field data for estimation of the infiltration characteristics. Recent work has proposed scaling the commonly used infiltration function by using a model infiltration curve and a single advance point for every other furrow in an irrigation event. Scaling factors were calculated for a series of furrows at two sites and at four points down the length of the field (0.25 L, 0.5 L, 0.75 L and L). Differences in the value of the scaling factor with distance were found to be a function of the shape of the advance curves. It is concluded that use of points early in the advance results in a substantial loss of accuracy and should be avoided. The scaling factor was also strongly correlated with the furrow-wetted perimeter suggesting that the scaling is an appropriate way of both predicting and accommodating the effect of the hydraulic variability

    Impact and experiences of delayed discharge: A mixed-studies systematic review

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    BACKGROUND: The impact of delayed discharge on patients, health-care staff and hospital costs has been incompletely characterized. AIM: To systematically review experiences of delay from the perspectives of patients, health professionals and hospitals, and its impact on patients' outcomes and costs. METHODS: Four of the main biomedical databases were searched for the period 2000-2016 (February). Quantitative, qualitative and health economic studies conducted in OECD countries were included. RESULTS: Thirty-seven papers reporting data on 35 studies were identified: 10 quantitative, 8 qualitative and 19 exploring costs. Seven of ten quantitative studies were at moderate/low methodological quality; 6 qualitative studies were deemed reliable; and the 19 studies on costs were of moderate quality. Delayed discharge was associated with mortality, infections, depression, reductions in patients' mobility and their daily activities. The qualitative studies highlighted the pressure to reduce discharge delays on staff stress and interprofessional relationships, with implications for patient care and well-being. Extra bed-days could account for up to 30.7% of total costs and cause cancellations of elective operations, treatment delay and repercussions for subsequent services, especially for elderly patients. CONCLUSIONS: The poor quality of the majority of the research means that implications for practice should be cautiously made. However, the results suggest that the adverse effects of delayed discharge are both direct (through increased opportunities for patients to acquire avoidable ill health) and indirect, secondary to the pressures placed on staff. These findings provide impetus to take a more holistic perspective to addressing delayed discharge
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