Ophthalmology. 2011 Dec;118(12):2343-50. doi: 10.1016/j.ophtha.2011.06.016. Epub 2011 Sep 1. Randomized, controlled trial of an educational intervention to promote spectacle use in rural China: the see well to learn well study.

OBJECTIVE: To test an educational intervention promoting the purchase of spectacles among Chinese children. DESIGN: Randomized, controlled trial. PARTICIPANTS: Children in years 1 and 2 of all 20 junior and senior high schools (ages 12-17 years) in 3 rural townships in Guangdong, China. METHODS: Children underwent visual acuity (VA) testing, and parents of participants with presenting VA worse than 6/12 in either eye improving by more than 2 lines with cycloplegic refraction were recommended to purchase glasses. Children at 10 randomly selected schools received a lecture, video, and classroom demonstration promoting spectacle purchase. MAIN OUTCOME MEASURES: Self-reported purchase of spectacles (primary outcome) and observed wear or possession of newly purchased glasses (secondary outcome) at follow-up examinations (mean, 219 ± 87 days after the baseline visit). RESULTS: Among 15 404 eligible children, examinations were completed for 6379 (74.6%) at intervention schools and 5044 (73.6%) at control schools. Spectacles were recommended for 2236 (35.1%) children at intervention schools and for 2212 (43.9%) at control schools. Of these, 417 (25.7%) intervention schools children and 537 (34.0%, P = 0.45) control schools children reported buying glasses. Predictors of purchase in regression models included female gender (P = 0.02), worse uncorrected VA (P < 0.001), and higher absolute value of refractive error (P = 0.001). Neither the rate of self-reported purchase of glasses or observed wear or possession of newly purchased glasses differed between control schools and intervention schools in mixed-effect logistic regression models. Among children not purchasing glasses, 21.7% had better-eye VA of worse than 6/18. CONCLUSIONS: An intervention based on extensive pilot testing and focus groups in the area failed to promote spectacle purchase or wear. The high burden of remaining uncorrected poor vision underscores the need to develop better interventions. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

A Phase-field Model for Computer Simulation of Lamellar Structure Formation in y-TiAI

In the present paper, a phase-field model is developed to simulate the formation and evolution of lamellar microstructure in γ-TiAl alloys. The mechanism of formation of TiAl lamellae proposed by Denquin and Naka is incorporated into the model. The model describes the formation and evolution of the face-centered cubic (fcc) stacking lamellar zone followed by the subsequent appearance and growth of the γ-phase, involving both the chemical composition change by atom transfer and the ordering of the fcc lattice. The thermodynamics of the model system and the interaction between the displacive and diffusional transformations are described by a non-equilibrium free energy formulated as a function of concentration and structural order parameter fields. The long-range elastic interactions, arising from the lattice misfit between the α, fcc (A1) and the various orientation variants of the γ-phase are taken into account by incorporating of the elastic strain energy into the total free energy. Simulation studies based on the model successfully predicted some essential features of the lamellar structure. It is found that the formation and evolution of the lamellar structure are predominantly controlled by the minimization of the elastic energy of the interfaces between the different fcc stacking groups, low-symmetry product phase γ and the high-symmetry α-phase, as well as between the various orientation variants of the product phase.

Oxidative stress in lavage fluid of preterm infants at risk of chronic lung disease

There is evidence that oxidative stress plays a role in the development of chronic lung disease (CLD), with immature lungs being particularly sensitive to the injurious effect of oxygen and mechanical ventilation. We analyzed total ascorbate, urate, and protein carbonyls in 102 bronchoalveolar lavage fluid samples from 38 babies (33 preterm, 24–36 wk gestation; 5 term, 37–39 wk gestation). Preterm babies had significantly decreasing concentrations of ascorbate, urate, and protein carbonyls during the first 9 days of life (days 1–3, 4–6, and 7–9, Kruskal-Wallis ANOVA: P 5 0.016, P , 0.0001, and P 5 0.010, respectively). Preterm babies had significantly higher protein carbonyl concentrations at days 1–3 and 4–6 (P 5 0.005 and P 5 0.044) compared with term babies. Very preterm babies (24–28 wk gestation) had increased concentrations of protein carbonyls at days 4–6 (P 5 0.056) and significantly decreased ascorbate concentrations at days 4–6 (P 5 0.004) compared with preterm babies (29–36 wk gestation). Urate concentrations were significantly elevated at days 1–3 (P 5 0.023) in preterm babies who subsequently developed CLD. This study has shown the presence of oxidative stress in the lungs of preterm babies during ventilation, especially in those who subsequently developed CLD.

Family-based investigation of the C677T polymorphism of the methylenetetrahydrofolate reductase gene in ischaemic heart disease

Background: Elevated homocysteine is associated with ischaemic heart disease (IHD). The C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene results in reduced MTHFR enzyme activity and reduced methylation of homocysteine to methionine resulting in mild hyperhomocysteinaemia. Case-control association studies of the role of the C677T MTHFR polymorphism in IHD have produced conflicting results. We therefore used newly described family-based association tests to investigate the role of this polymorphism in IHD, in a well-defined population. Methods: A total of 352 individuals from 129 families (discordant sibships and parent-child trios) were recruited. Linkage disequilibrium between the polymorphism and IHD was tested for using the combined transmission disequilibrium test (TDT)/sib-TDT and pedigree disequilibrium test (PDT). Homocysteine levels were measured. Results: Both the TDT/sib-TDT and PDT analyses found a significantly reduced transmission of the T allele to affected individuals (P=0.016 and P=0.021). There was no significant difference in homocysteine levels between affected and unaffected siblings. TT homozygotes had mean homocysteine levels significantly higher than those of TC heterozygotes (P

Deep sampling and testing in soft stratified clay

A 37-m thick layer of stratified clay encountered during a site investigation at Swann's Bridge, near the sea-coast at Limavady, Northern Ireland, is one of the deepest and thickest layers of this type of material recorded in Ireland. A study of the relevant literature and stratigraphic evidence obtained from the site investigation showed that despite being close to the current shoreline, the clay was deposited in a fresh-water glacial lake formed approximately 13 000 BP. The 37-m layer of clay can be divided into two separate zones. The lower zone was deposited as a series of laminated layers of sand, silt, and clay, whereas the upper zone was deposited as a largely homogeneous mixture. A comprehensive series of tests was carried out on carefully selected samples from the full thickness of the deposit. The results obtained from these tests were complex and confusing, particularly the results of tests done on samples from the lower zone. The results of one-dimensional compression tests, unconsolidated undrained triaxial tests, and consolidated undrained triaxial compression tests showed that despite careful sampling, all of the specimens from the lower zone exhibited behaviour similar to that of reconstituted clays. It was immediately clear that the results needed explanation. This paper studies possible causes of the results from tests carried out on the lower Limavady clay. It suggests a possible mechanism based on anisotropic elasticity, yielding, and destructuring that provides an understanding of the observed behaviour.Key words: clay, laminations, disturbance, yielding, destructuring, reconstituted.

Simultaneous feature selection and feature weighting using Hybrid Tabu Search/K-nearest neighbor classifier

Feature selection and feature weighting are useful techniques for improving the classification accuracy of K-nearest-neighbor (K-NN) rule. The term feature selection refers to algorithms that select the best subset of the input feature set. In feature weighting, each feature is multiplied by a weight value proportional to the ability of the feature to distinguish pattern classes. In this paper, a novel hybrid approach is proposed for simultaneous feature selection and feature weighting of K-NN rule based on Tabu Search (TS) heuristic. The proposed TS heuristic in combination with K-NN classifier is compared with several classifiers on various available data sets. The results have indicated a significant improvement in the performance in classification accuracy. The proposed TS heuristic is also compared with various feature selection algorithms. Experiments performed revealed that the proposed hybrid TS heuristic is superior to both simple TS and sequential search algorithms. We also present results for the classification of prostate cancer using multispectral images, an important problem in biomedicine.

Investigations on the adsorption of acidic gases using activated dolomite

In this work activated dolomite adsorption was investigated for removal of acidic gaseous pollutants. Charring was found to be an effective method for the activation of dolomite. This thermal processing resulted in partial decomposition, yielding a calcite and magnesium oxide structure. Adsorbents were produced over a range of char temperatures (750, 800 and 850 °C) and char times (1–8 h). The surface properties and the adsorption capability of raw and thermally treated dolomite sorbents were investigated using porosimetry, SEM and XRD. The sorbates individually investigated were CO2 and NO2. Volumetric equilibrium isotherm determinations were produced in order to quantify sorbate capacity on the various sorbents. The equilibrium data were successfully described using the Freundlich isotherm model. Despite relatively low surface area characteristics of the activated dolomite, there was a high capacity for the acidic gas sorbates investigated, showing a maximum of 12.6 mmol/g (554 mg/g) for CO2 adsorption and 9.93 mmol/g (457 mg/g) for NO2 adsorption. Potentially the most cost effective result from the work concerns the adsorptive capacity for the naturally occurring material, which gave a capacity of 9.71 mmol/g (427 mg/g) for CO2 adsorption and 4.18 mmol/g (193 mg/g) for NO2 adsorption. These results indicate that dolomitic sorbents are potentially cost effective materials for acidic gases adsorption.

Epipolar geometry estimation based on evolutionary agents

This paper presents a novel approach based on the use of evolutionary agents for epipolar geometry estimation. In contrast to conventional nonlinear optimization methods, the proposed technique employs each agent to denote a minimal subset to compute the fundamental matrix, and considers the data set of correspondences as a 1D cellular environment, in which the agents inhabit and evolve. The agents execute some evolutionary behavior, and evolve autonomously in a vast solution space to reach the optimal (or near optima) result. Then three different techniques are proposed in order to improve the searching ability and computational efficiency of the original agents. Subset template enables agents to collaborate more efficiently with each other, and inherit accurate information from the whole agent set. Competitive evolutionary agent (CEA) and finite multiple evolutionary agent (FMEA) apply a better evolutionary strategy or decision rule, and focus on different aspects of the evolutionary process. Experimental results with both synthetic data and real images show that the proposed agent-based approaches perform better than other typical methods in terms of accuracy and speed, and are more robust to noise and outliers.

Extension of the Ye and Shreeve group contribution method for density estimation of ionic liquids in a wide range of temperatures and pressures

An extension of the Ye and Shreeve group contribution method [C. Ye, J.M. Shreeve, J. Phys. Chem. A 111 (2007) 1456–1461] for the estimation of densities of ionic liquids (ILs) is here proposed. The new version here presented allows the estimation of densities of ionic liquids in wide ranges of temperature and pressure using the previously proposed parameter table. Coefficients of new density correlation proposed were estimated using experimental densities of nine imidazolium-based ionic liquids. The new density correlation was tested against experimental densities available in literature for ionic liquids based on imidazolium, pyridinium, pyrrolidinium and phosphonium cations. Predicted densities are in good agreement with experimental literature data in a wide range of temperatures (273.15–393.15 K) and pressures (0.10–100 MPa). For imidazolium-based ILs, the mean percent deviation (MPD) is 0.45% and 1.49% for phosphonium-based ILs. A low MPD ranging from 0.41% to 1.57% was also observed for pyridinium and pyrrolidinium-based ILs.