An evaluation of a series of sixth grade compositions to determine growth in originality, elaborative thinking, and vocabulary

Thesis (Ed.M.)--Boston Universit

Preschool children's vision screening in New Zealand: a retrospective evaluation of referral accuracy

Langeslag-Smith MA, Vandal AC, Briane V, et al. Preschool children's vision screening in New Zealand: a retrospective evaluation of referral accuracy. BMJ Open 2015;5:e009207. doi: 10.1136/bmjopen-2015-009207Objectives To assess the accuracy of preschool vision screening in a large, ethnically diverse, urban population in South Auckland, New Zealand. Design Retrospective longitudinal study. Methods B4 School Check vision screening records (n=5572) were compared with hospital eye department data for children referred from screening due to impaired acuity in one or both eyes who attended a referral appointment (n=556). False positive screens were identified by comparing screening data from the eyes that failed screening with hospital data. Estimation of false negative screening rates relied on data from eyes that passed screening. Data were analysed using logistic regression modelling accounting for the high correlation between results for the two eyes of each child. Primary outcome measure Positive predictive value of the preschool vision screening programme. Results Screening produced high numbers of false positive referrals, resulting in poor positive predictive value (PPV=31%, 95% CI 26% to 38%). High estimated negative predictive value (NPV=92%, 95% CI 88% to 95%) suggested most children with a vision disorder were identified at screening. Relaxing the referral criteria for acuity from worse than 6/9 to worse than 6/12 improved PPV without adversely affecting NPV. Conclusions The B4 School Check generated numerous false positive referrals and consequently had a low PPV. There is scope for reducing costs by altering the visual acuity criterion for referral.This work was supported by the Arthur D Bronlund Trust, CCRep and University of Auckland Faculty Research Development Fund Grants (3704420)

Corrosion inhibitors for the rehabilitation of reinforced concrete

Four corrosion inhibitors namely sodium nitrite, sodium monofluorophosphate, ethanolamine and an alkanolamine-based mixture were studied by immersing mild steel bars for 42 days in model electrolytes of varied pH and chloride concentration which were intended to simulate the pore solution phase present within carbonated and/or chloride-contaminated concrete. Site trials were carried out on sodium monofluorophosphate and the alkanolamine-based inhibitor to study their depth of penetration into concrete. The influence of various carbonating atmospheres on the pore solution chemistry and microstructure of hydrated cement paste was investigated. Physical realkalisation of carbonated cement paste and a calcium nitrite-based corrosion rehabilitation system for chloride-contaminated cement paste were investigated by monitoring ionic transport within the pore solution phase of laboratory specimens. The main findings were as follows: 1,Sodium nitrite, sodium monofluorophosphate, ethanolamine and the alkanolamine-based mixture all behaved as passivating anodic inhibitors of steel corrosion in air-saturated aqueous solutions of varied pH and chloride concentration. 2,Sodium monofluorophosphate failed to penetrate significantly into partially carbonated site concrete when applied as recommended by the supplier. Phosphate and fluoride penetrated 5mm into partially carbonated site concrete treated with sodium monofluorophosphate. 3,The ethanolamine component of the alkanolamine-based inhibitor was found to have penetrated significant depths into partially carbonated site concrete. 4,Carbonating hydrated cement paste over saturated solutions of sodium nitrite resulted in significant concentrations of nitrite in the pore solution of the carbonated paste. Saturated solutions of sodium chloride, ammonium nitrate, magnesium nitrate and sodium dichromate were investigated and identified as alternatives for controlling the relative humidity of the carbonating environment. 5,Hardened carbonated cement paste can by physically realkalised to a limited extent due to the diffusion of hydroxyl ions under saturated conditions. A substantial proportion of the hydroxyl ions that diffused into the carbonated cement paste however, became bound into the cement matrix. Hydroxyl ion concentrations remained below 5mmol/l within the pore solution of the realkalised cement paste. 6, Nitrite ions penetrated significant distances by diffusion within the pore solution of saturated uncarbonated hydrated cement paste

Prenatal exposure to recreational drugs affects global motion perception in preschool children

Chakraborty, A. et al. Prenatal exposure to recreational drugs affects global motion perception in preschool children. Sci. Rep. 5, 16921; doi: 10.1038/srep16921 (2015).Prenatal exposure to recreational drugs impairs motor and cognitive development; however it is currently unknown whether visual brain areas are affected. To address this question, we investigated the effect of prenatal drug exposure on global motion perception, a behavioural measure of processing within the dorsal extrastriate visual cortex that is thought to be particularly vulnerable to abnormal neurodevelopment. Global motion perception was measured in one hundred and forty-five 4.5-year-old children who had been exposed to different combinations of methamphetamine, alcohol, nicotine and marijuana prior to birth and 25 unexposed children. Self-reported drug use by the mothers was verified by meconium analysis. We found that global motion perception was impaired by prenatal exposure to alcohol and improved significantly by exposure to marijuana. Exposure to both drugs prenatally had no effect. Other visual functions such as habitual visual acuity and stereoacuity were not affected by drug exposure. Prenatal exposure to methamphetamine did not influence visual function. Our results demonstrate that prenatal drug exposure can influence a behavioural measure of visual development, but that the effects are dependent on the specific drugs used during pregnancy.This research was supported by the National Institutes on Drug Abuse grants 2RO1DA014948 and RO1DA021757 and the Auckland Medical Research Foundation

Determination of the selectivity coefficient of a chloride ion selective electrode in alkaline media simulating the cement paste pore solution.

The measurement of the free chloride concentration in the pore solution of cement paste or concrete is of interest for assessing the probability of corrosion of the steel reinforcements embedded in concrete. This determination is performed through leaching or pore-pressing methods or through embedded potentiometric sensors into the hardened cementitious material. The potentiometric determination of chloride in cement paste pore solutions is limited by hydroxide ion interference, due to the high alkalinity of such media. The potentiometric selectivity coefficients, kCl-,OH-, are determined for a chloride ionic selective electrode in alkaline solutions simulating the electrolyte present within the pore network of cement paste and concrete. This is done using a fixed interference methodology, with least-squares non-linear curve fitting for obtaining the selectivity coefficients together with other relevant electrode parameters. The limit of detection of the Cl− ISE, due to OH− interference, varies with pH. For the pore solution corresponding to an ordinary Portland cement paste or concrete, this limit can be set between 3 × 10–3 m, and 7 × 10–3 m, i.e., approximately below a chloride concentration value of 1 × 10–2 molal. Taking into account these limits of detection the free Cl− concentrations able to depassivate the steel, can be adequately determined by potentiometric measurements with calibrated ISEs in the expressed pore solutions of Portland cement concretes, without significant influence of OH− interference. Nevertheless, this effect can prevent the adequate measurement of low free Cl− concentrations, below the corresponding limit of detection valu

Neonatal Glycemia and Neurodevelopmental Outcomes at 2 Years

From McKinlay, C. J. D., Alsweiler, J. M., Ansell, J. M., Anstice, N. S., Chase, J. G., Gamble, G. D., … Harding, J. E. (2015). Neonatal Glycemia and Neurodevelopmental Outcomes at 2 Years. New England Journal of Medicine, 373(16), 1507–1518. https://doi.org/10.1056/NEJMoa1504909 Copyright © 2015 Massachusetts Medical Society. Reprinted with permission.Neonatal hypoglycemia is a common and readily treatable risk factor for neurologic impairment in children. Although associations between prolonged symptomatic neonatal hypoglycemia and brain injury are well established,1 the effect of milder hypoglycemia on neurologic development is uncertain.2 Consequently, large numbers of newborns are screened and treated for low blood glucose concentrations, which involves heel-stick blood tests, substantial costs, and the possibility of iatrogenic harm. Under current guidelines,3 up to 30% of neonates are considered to be at risk for hypoglycemia, 15% receive a diagnosis of hypoglycemia, and approximately 10% require admission to a neonatal intensive care unit,4 costing an estimated $2.1 billion annually in the United States alone.5 Associated formula feeding and possible separation of mother and baby reduce breast-feeding rates,6 with potentially adverse effects on broader infant health and development. In addition, pain-induced stress in neonates, such as repeated heel sticks, may itself impair brain development.7 Thus, to determine appropriate glycemic thresholds for treatment, there have been repeated calls for studies of the effect of neonatal hypoglycemia on long-term development.2,8 We report the results of the Children with Hypoglycaemia and Their Later Development (CHYLD) study, a large prospective cohort study of term and late-preterm neonates born at risk for hypoglycemia. The study investigated the relation between the duration, frequency, and severity of low glucose concentrations in the neonatal period and neuropsychological development at 2 years.Supported by grants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01HD069622), the Health Research Council of New Zealand (10-399), and the Auckland Medical Research Foundation (1110009)

Efficacy of a gas permeable contact lens to induce peripheral myopic defocus

Purpose. The purpose of this work was to evaluate the potential of a novel custom-designed rigid gas permeable (RGP) contact lens to modify the relative peripheral refractive error in a sample of myopic patients. Methods. Fifty-two right eyes of 52 myopic patients (mean [TSD] age, 21 [T2] years) with spherical refractive errors ranging from j0.75 to j8.00 diopters (D) and refractive astigmatism of 1.00 D or less were fitted with a novel experimental RGP (ExpRGP) lens designed to create myopic defocus in the peripheral retina. A standard RGP (StdRGP) lens was used as a control in the same eye. The relative peripheral refractive error was measured without the lens and with each of two lenses (StdRGP and ExpRGP) using an open-field autorefractometer from 30 degrees nasal to 30 degrees temporal, in 5-degree steps. The effectiveness of the lens design was evaluated as the amount of relative peripheral refractive error difference induced by the ExpRGP compared with no lens and with StdRGP conditions at 30 degrees in the nasal and temporal (averaged) peripheral visual fields. Results. Experimental RGP lens induced a significant change in relative peripheral refractive error compared with the nolens condition (baseline), beyond the 10 degrees of eccentricity to the nasal and temporal side of the visual field (p G 0.05). The maximum effect was achieved at 30 degrees. Wearing the ExpRGP lens, 60% of the eyes had peripheral myopia exceeding j1.00 D, whereas none of the eyes presented with this feature at baseline. There was no significant correlation (r = 0.04; p = 0.756) between the degree of myopia induced at 30 degrees of eccentricity of the visual field with the ExpRGP lens and the baseline refractive error. Conclusions. Custom-designed RGP contact lenses can generate a significant degree of relative peripheral myopia in myopic patients regardless of their baselin spherical equivalent refractive error.Jaume Paune´ has proprietary and financial interests in the manufacturing and distribution of lenses evaluated in this study. The remaining authors declare that they do not have any proprietary or financial interest in any of the materials mentioned in this article. This work was partially funded by Fundação para Ciência e Tecnologia, Portugal, Projects: PTDC/SAU-BEB/ 098392/2008 and PTDC/SAU-BEB/098391/200

The implementation and enforcement of the obligation under the international law of armed conflict to take precautions in attack (1980-2005).

Existing international legal literature recognizes that parties to armed conflicts and individual combatants are legally required not only to refrain from deliberately attacking non-combatants and civilian objects, but also to take care to ensure (to the extent feasible) that such persons are not killed or injured, and such objects not destroyed or damaged, by accident or incidentally during military operations. This thesis looks at the practical application of this latter principle during a twenty-five year period following the entry into force of Protocol I Additional to the Geneva Conventions of 1949. It contends that although the rules in this area are not easily susceptible to judicial enforcement, they are nevertheless sufficiently flexible and realistic to be capable of effective implementation without detriment to military effectiveness. Examination of the practice of parties to various conflicts during the period under review suggests that if and to the extent that belligerents are ready to devote time and resources to training, leadership, internal accountability procedures, and to the provision of appropriate military equipment, they can, so long as they are not too impatient for quick results, comply with the Protocol I rules on precaution in attack without the need for combatants to take unreasonable risks for the sake of enemy non-combatants. Efforts to enforce the law externally have, however, met with mixed results, revealing more about the selectivity of international justice than about its effectiveness as a tool for ensuring fair treatment for victims and alleged violators of the rules on precautions in attack. The most potentially effective form of enforcement of these rules appears set to remain, for the time being at least, the influence over belligerents which some third party states and other international actors retain, but are perhaps sometimes hesitant to exercise in the interests of promoting respect for the law of armed conflict

Global prevalence of childhood cataract: a systematic review

Childhood cataract is an avoidable cause of visual disability worldwide and is a priority for VISION 2020: The Right to Sight. There is a paucity of information about the burden of cataract in children and the aim of this review is to assess the global prevalence of childhood cataract. The methodology for the review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We performed a literature search for studies reporting estimates of prevalence or incidence of cataract among children (aged<18 years) at any global location using the Cochrane Library, Medline and Embase up to January 2015. No restrictions were imposed based on language or year of publication. Study quality was assessed using a critical appraisal tool designed for systematic reviews of prevalence. Twenty prevalence and four incidence studies of childhood cataract from five different geographical regions were included. The overall prevalence of childhood cataract and congenital cataract was in the range from 0.32 to 22.9/10000 children (median=1.03) and 0.63 to 9.74/10000 (median=1.71), respectively. The incidence ranged from 1.8 to 3.6/10000 per year. The prevalence of childhood cataract in low-income economies was found to be 0.42 to 2.05 compared with 0.63 to 13.6/10000 in high-income economies. There was no difference in the prevalence based on laterality or gender. This review highlights substantial gaps in the epidemiological knowledge of childhood cataract worldwide, particularly from low and lower middle-income economies. More studies are needed using standard definitions and case ascertainment methods with large enough sample sizes

Geoscience of the built environment: pollutants and materials surfaces

An overview of issues with environmental relevance that arise from the interaction between pollutants and surfaces of the built environment is presented in this paper. Two broad perspectives are considered: decay of materials and recording of pollution characteristics. In relation to the former, we consider the possible implications on human activities restrictions, materials and morphological options, consumption of resources and release of pollutants resulting from the alteration of materials, conservation and restoration procedures. In terms of pollution recording, the interest of the stony materials as passive monitors of pollution, the question of heterogeneous conditions on buildings and the interest of qualitative and quantitative studies are highlighted. The importance of longitudinal studies on new and cleaned surfaces is considered, both for the understanding of materials decay and for the assessment of pollution conditions. The use of tracers to record the characteristics of pollution sources, interaction with materials and pathways of pollutants is also discussed. Finally, some recommendations are presented, based on the issues discussed on this paper that might be relevant for environmental management programs, including environmental education.Fundação para a Ciência e Tecnologia (Portugal) (programa plurianual das unidades de investigação; PEst-OE/CTE/UI0697/2011)Fundação das Universidades PortuguesaMinisterio de Ciencia e Innovación - Acción Integrada PT2009-007