Synthesis and structure of tris(triphenyltin)benzene-1,3,5-tricarboxylate and its tri-DMSO adduct

The molecular structure of (Ph₃SnO₂C)₃C₆H₃ reveals distorted tetrahedral C₃O geometries for each tin atom. No intermolecular Sn...O associations occur between the molecules so that the trinuclear molecule may be considered monomeric. An increase in coordination number at tin is indicated by ¹¹⁹Sn NMR measurements conducted in d₆-DMSO solution and this has been confirmed by a structure analysis of (DMSO·Ph₃SnO₂C)₃C₆H₃·2 DMSO. In this structure, the tin atom geometries are distorted trigonal bipyramidal, existing within trans-C₃O₂ donor sets. Thus, while is it possible for the tin atoms to increase their coordination numbers in (Ph₃SnO₂C)₃C₆H₃, molecular aggregation to form polymeric arrays is precluded, most likely due to steric constraints.

Synthesis and structure of 1,3,5-tris(diorganohydroxysilyl)benzenes. Novel building blocks in supramolecular silanol chemistry

The 1,3,5-tris(diorganohydroxysilyl)benzenes 1,3,5-(HOR₂Si)₃C₆H₃ (TMSB, R = Me; TPSB, R = Ph) have been prepared and fully characterized by X-ray crystallography. The crystal structure of TMSB features pairwise connected layers, in which the molecules are involved in interlayer hydrogen bonding. The supramolecular hydrogen bond motif may be described as a 12-membered ring that adopts a chair conformation. TPSB forms an equimolar inclusion complex with water, which is associated via hydrogen bonding and apparently fills a void in the crystal packing. In this case, the supramolecular hydrogen bond motif may be described as an eight-membered ring. Two of the water molecules are also associated, giving rise to a water dimer entrapped in the silanol matrix. Besides the hydrogen bonds, the crystal structure of the TPSB·H₂O complex reveals intra- and intermolecular C-H··· π stacking of most of the phenyl groups. Electrospray mass spectrometry shows that TPSB undergoes supramolecular complex formation with a variety of N-donors such as 4-(dimethylamino)pyridine, N,N,N',N'-tetramethylethylenediamine, imidazole, 2-(dimethylamino)pyridine, and 2,2'-dipyridylamine.

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A pilot study of a telephone-based parental intervention to increase fruit and vegetable consumption in 3-5 year old children

Objective : To examine the potential efficacy of a brief telephone-based parental intervention in increasing fruit and vegetable consumption in children aged 3–5 years and to examine the feasibility of intervention delivery and acceptability to parents.

Design : A pre–post study design with no comparison group. Telephone surveys were conducted approximately 1 week before and following intervention delivery.
Setting Participants were recruited through pre-schools in the Hunter region, New South Wales, Australia.

Subjects : Thirty-four parents of 3–5-year-olds received four 30-min interventional telephone calls over 4 weeks administered by trained telephone interviewers. The scripted support calls focused on fruit and vegetable availability and accessibility within the home, parental role modelling of fruit and vegetable consumption and on implementing supportive family eating routines.

Results : Following the intervention, the frequency and variety of fruit and vegetable consumption increased (P = 0·027), as measured by a subscale of the children's dietary questionnaire. The intervention was feasible to be delivered to parents, as all participants who started the intervention completed all four calls, and all aspects of the interventional calls, including the number, length, content, format and relevance, were considered acceptable by more than 90 % of parents.

Conclusions : A brief telephone-based parental intervention to encourage fruit and vegetable consumption in pre-school-aged children may be effective, feasible and acceptable. Further investigation is warranted in a randomised controlled trial.

What hispanic parents do to encourage and discourage 3-5 year old children to be active : a qualitative study using nominal group technique

Purpose : Hispanic preschoolers are less active than their non-Hispanic peers. As part of a feasibility study to assess environmental and parenting influences on preschooler physical activity (PA) (Niños Activos), the aim of this study was to identify what parents do to encourage or discourage PA among Hispanic 3-5 year old children to inform the development of a new PA parenting practice instrument and future interventions to increase PA among Hispanic youth.

Methods : Nominal Group Technique (NGT), a structured multi-step group procedure, was used to elicit and prioritize responses from 10 groups of Hispanic parents regarding what parents do to encourage (5 groups) or discourage (5 groups) preschool aged children to be active. Five groups consisted of parents with low education (less than high school) and 5 with high education (high school or greater) distributed between the two NGT questions.

Results : Ten NGT groups (n = 74, range 4-11/group) generated 20-46 and 42-69 responses/group for practices that encourage or discourage PA respectively. Eight to 18 responses/group were elected as the most likely to encourage or discourage PA. Parental engagement in child activities, modeling PA, and feeding the child well were identified as parenting practices that encourage child PA. Allowing TV and videogame use, psychological control, physical or emotional abuse, and lack of parental engagement emerged as parenting practices that discourage children from being active. There were few differences in the pattern of responses by education level.

Conclusions : Parents identified ways they encourage and discourage 3-5 year-olds from PA, suggesting both are important targets for interventions. These will inform the development of a new PA parenting practice scale to be further evaluated. Further research should explore the role parents play in discouraging child PA, especially in using psychological control or submitting children to abuse, which were new findings in this study.

Corrosion behavior of Mg-5Al-xZn alloys in 3.5 wt.% NaCl solution

Five types of Mg-5Al alloys with different weight percentages of Zn ranging from 0 to 4 wt.% were examined using electrochemical techniques and surface analysis. The electrochemical results indicated that the Mg-5Al alloys containing Zn have a lower corrosion and hydrogen evolution rates than the Mg-5Al based specimens with a decrease of value being observed with the decrease in Zn content. Zn addition induced the precipitation of Mg-Al and Mg-Zn phases in the Mg matrix along with grain refinement and increased an interaction of Zn oxide with Mg and Al products serving as a corrosion barrier. © 2014 Elsevier B.V. All rights reserved.

The predictors of diet quality among Australian children aged 3.5 years

BACKGROUND: It is critical to promote healthy eating early in life. OBJECTIVE: The aim of this study was to examine diet quality and its predictors among Australian preschool-aged children. DESIGN: Diet was assessed at age 3.5 years using multiple 24-hour recalls. Diet quality was assessed using an adapted version of the Revised Children's Diet Quality Index (RC-DQI). Potential predictors of diet quality were from questionnaires at age 3, 9, and 18 months and informed by the ecologic model of childhood overweight. Potential predictors included child's sex, age of introduction to solid foods, breastfeeding status, food acceptance, maternal nutrition knowledge, modeling of healthy eating, self-efficacy, education, and home food availability. PARTICIPANTS: Data from 244 children participating in the Melbourne Infant Feeding, Activity, and Nutrition Trial in 2008-2010 and follow-up data collection in 2011-2013 were examined. MAIN OUTCOME MEASURES: Diet quality at age 3.5 years. STATISTICAL ANALYSES PERFORMED: Bivariate logistic regression was performed to assess the relationship between diet quality and each predictor. A multivariable logistic regression model accounting for influences of covariates, treatment arm, and clustering by group tested associations between diet quality and significant predictors from bivariate analyses. RESULTS: RC-DQI scores had a mean±standard deviation score of 62.8±8.3 points out of a maximum of 85 points. Breastfeeding status (odds ratio [OR] 2.34, 95% CI 1.33 to 4.10) and maternal modeling of healthy eating (OR 1.75, 95% CI 1.01 to 3.03) were positively associated with RC-DQI scores. Both breastfeeding status (OR 3.09, 95% CI 1.63 to 5.85) and modeling (OR 2.01, 95% CI 1.04 to 3.88) remained positively associated with diet quality after adjustment for child age, body mass index z score, energy intake, treatment arm, and clustering. CONCLUSIONS: Breastfeeding status and modeling of healthy eating were independently associated with children's diet quality. Early intervention could assist mothers to practice these behaviors to provide support for improving child diet quality.

Glaucomatous visual field progression with frequency-doubling technology and standard automated perimetry in a longitudinal prospective study

PURPOSE. To compare frequency-doubling technology (FDT) perimetry with standard automated perimetry (SAP) for detecting glaucomatous visual field progression in a longitudinal prospective study.

METHODS. One eye of patients with open-angle glaucoma was tested every 6 months with both FDT and SAP. A minimum of 6 examinations with each perimetric technique was required for inclusion. Visual field progression was determined by two methods: glaucoma change probability (GCP) analysis and linear regression analysis (LRA). For GCP, several criteria for progression were used. The number of locations required to classify progression with FDT compared with SAP, respectively, was 1:2 (least conservative), 1:3, 2:3, 2:4, 2:6, 2:7, 3:6, 3:7, and 3:10 (most conservative). The number of consecutive examinations required to confirm progression was 2-of-3, 2-of-2, and 3-of-3. For LRA, the progression criterion was any significant decline in mean threshold sensitivity over time in each of the following three visual field subdivisions: (1) all test locations, (2) locations in the central 10° and the superior and inferior hemifields, and (3) locations in each quadrant. Using these criteria, the proportion of patients classified as showing progression with each perimetric technique was calculated and, in the case of progression with both, the differences in time to progression were determined.

RESULTS. Sixty-five patients were followed for a median of 3.5 years (median number of examinations, 9). For the least conservative GCP criterion, 32 (49%) patients were found to have progressing visual fields with FDT and 32 (49%) patients with SAP. Only 16 (25%) patients showed progression with both methods, and in most of those patients, FDT identified progression before SAP (median, 12 months earlier). The majority of GCP progression criteria (15/27), classified more patients as showing progression with FDT than with SAP. Contrary to this, more patients showed progression with SAP than FDT, when analysed with LRA; e.g., using quadrant LRA 20 (31%) patients showed progression with FDT, 23 (35%) with SAP, and only 10 (15%) with both.

CONCLUSIONS. FDT perimetry detected glaucomatous visual field progression. However, the proportion of patients who showed progression with both FDT and SAP was small, possibly indicating that the two techniques identify different subgroups of patients. Using GCP, more patients showed progression with FDT than with SAP, yet the opposite occurred using LRA. As there is no independent qualifier of progression, FDT and SAP progression rates vary depending on the method of analysis and the criterion used.