Search

Background: A 2010 publication showed a positive relationship between children's body mass index (BMI) and energy intake at school-provided meals (as assessed by direct meal observations). To help explain that relationship, we investigated 7 outcome variables concerning aspects of school-provided meals: energy content of items selected, number of meal components selected, number of meal components eaten, amounts eaten of standardized school-meal portions, energy intake from flavored milk, energy intake received in trades, and energy content given in trades. Methods: Fourth-grade children (N = 465) from Columbia, SC, were observed eating school-provided breakfast and lunch on 1 to 4 days per child. Researchers measured children's weight and height. For daily values at school meals, a generalized linear model was fit with BMI (dependent variable) and the 7 outcome variables, sex, and age (independent variables). Results: BMI was positively related to amounts eaten of standardized school-meal portions (p less than 0.0001) and increased 8.45 kg/m[superscript 2] per serving, controlling for other variables in the model. BMI was positively related to energy intake from flavored milk (p = 0.0041) and increased 0.347 kg/m[superscript 2] for every 100 kcal consumed. BMI was negatively related to energy intake received in trades (p = 0.0003) and decreased 0.468 kg/m[superscript 2] for every 100 kcal received. BMI was not significantly related to 4 outcome variables. Conclusions: Knowing that relationships between BMI and actual consumption, not selection, at school-provided meals explained the (previously found) positive relationship between BMI and energy intake at school-provided meals is helpful for school-based obesity interventions. (Contains 2 tables.)

Previous research on sensation seeking (SS) was dominated by a variable-oriented approach indicating that SS level has a linear relation with a host of problem behaviors. Our aim was to provide a person-oriented methodology--a probabilistic clustering--that enables examination of both inter- and intra-individual differences in not only the level, but also in the pattern of SS. We have applied model-based clustering to a four-semester long longitudinal high school survey ("N" = 3334) and to a cross-sectional university survey ("N" = 438). The results indicated that impulsive patterns are linked to negative outcomes whereas non-impulsive patterns are associated with positive outcomes. Our study aims to serve as a methodological example on how to apply model-based clustering to examine different types of sensation-seeking patterns. This modern clustering method allows for probabilistic categorization, with continuous typicality scores besides cluster membership variables. These typicality scores turned out to have higher temporal stability than simple categorical membership variables did. (Contains 4 figures and 3 tables.)

Purpose/Objectives: Analyses were conducted to examine variations in fourth-grade children's participation in school-breakfast and school-lunch programs by weekday, month, socioeconomic status, absenteeism, gender, and school-breakfast location. Methods: Fourth-grade children were participants in a dietary-reporting validation study during either the 2005-2006 or 2006-2007 school years in 17 or 8 schools, respectively, in one South Carolina school district. For the two school years, the location of the school breakfast was the classroom for 6 and 7 schools, respectively, and the cafeteria for the remaining schools. District administrative records provided information about 180 possible days of participation in the school breakfast and lunch programs for each of 1,060 children (91% Black, 52% girls). The state's Office of Research and Statistics linked data on school-meal participation with information about individual children's socioeconomic status (eligibility for free or reduced-price school meals) and annual absenteeism from school. Results: For school-provided breakfast, logistic regression showed participation rate differences by weekday (smallest for Monday [56.1%], largest for Wednesday [57.8%], "p" < 0.001), month (smallest for April [53.5%], largest for September [60.8%], "p" < 0.001), socioeconomic status (smallest for full-price status [27.5%], largest for free-meal status [63.4%], "p" < 0.001), school-breakfast location (smaller for breakfast located in the cafeteria [38%] than classroom [71%], "p" < 0.001), and absenteeism ("p" < 0.001). For school-provided lunch, logistic regression showed participation rate differences by weekday (smallest for Friday [81.9%], largest for Thursday [83.3%], "p" < 0.001), month (smallest for May [78.7%], largest for August [86.0%], "p" < 0.001), socioeconomic status (smallest for full-price status [72.1%], largest for free-meal status [84.9%], "p" < 0.001), and absenteeism ("p" < 0.001). There were no differences in participation rate by gender. Applications for Child Nutrition Professionals: Administrative participation records are used for forecasting purchasing and production. Using such records in research studies may provide insight into factors influencing children's participation in school-provided meals. Districts and managers are encouraged to share administrative records of children's participation in school-provided meals with researchers.

The novel binuclear titanium(IV) complex [{TiCl(OPr i)2(HOPr i )}2(mu-OPr i)2], 1, and the first mononuclear vanadyl(IV) chloroalcoholate [VCl(O)(HOPr i)4]Cl, 2, have been prepared from 2:1:1 mixtures of [Ti(OPr i)4], KOPr i and VCl3. Products were characterised by elemental analysis, FTIR, EPR, NMR and electronic spectroscopies, magnetic susceptibility measurements and single crystal X-ray diffractometry. A third product was found to be polynuclear and to contain both titanium and vanadium. Semi-empirical quantum-mechanical calculations were carried out for the evaluation of the electronic structure of 1.

The synthesis, spectroscopic characterisation and reactivity of a series of vanadium(II) complexes, [VCl2(diamine)2] (diamine = dmeda: N,N'-dimethylethane-1,2-diamine, deeda: N,N'diethylethane-1,2-diamine, tmeda: N,N,N',N'-tetramethylethane-1,2-diamine, dieda: N,N'diisopropylethane-1,2-diamine, teeda: N,N,N',N'-tetraethylethane-1,2-diamine, dtbeda: N,N'-ditert-butylethane-1,2-diamine and dfeda: N,N'-diphenylethane-1,2-diamine) are reported. Some of these complexes can be converted into the trinuclear cation [V3(µCl)3(µ3Cl)2(diamine) 3]+ through the reaction with [V2(µ-Cl)3(thf)3]+ under mild conditions. The compounds were characterised by microanalysis, positive ion FAB mass spectrometry, UVvisible and infrared spectroscopies, thermogravimetric analysis and magnetic moment measurements in the solid state. We characterised fully by single-crystal X-ray diffraction analysis the complex [VCl2(deeda)2]. The stability of [VCl2(diamine)2] as they vary with the different diamines is correlated with crystal field and infrared parameters along with decomposition temperatures and the calculated molecular orbital energies. We also presented a new synthetic route to prepare [V3(µ-Cl)3(µ3-Cl)2(diamine) 3]+ which allows a better control of the reaction pathway, avoiding the formation of undesired redox reaction products.

Reaction of Li(P3C2Bu t2 ) with BrCH(SiMe3)2 results in a novel organophosphorus compound with the formula, P6C4Bu t4 CHSiMe3 (1). Compound 1 was fully characterised spectroscopically and its unique molecular structure determined by single crystal X-ray diffraction. Another isomer (2) with a saturated structure was also fully characterised.

Investigation of the solution structures of [Ir4(CO)11L] (L = [Fe(eta5-P3C2Bu t2)(eta5-C5H 5)] (1) and [Fe(eta5-P3C2Bu t2)(eta5-P2C 3Bu t3)] (2) by 13C and 31P NMR spectroscopy showed that, at 163K, 1 exists in the form of two isomers with bridged and non-bridged structures, in a 1:0.15 ratio, respectively, whereas 2 exists only in the bridged form. At RT, 1,2 shift of the eta5-P3C2Bu t 2 ring was only observed for compound 2. Where as 2 loses CO readily in solution to give [Ir4(CO)10{mu-eta¹-eta¹-[Fe(eta5-P3C2 Bu t2)(eta5-P2 C3Bu t3)}] (3), activation with Me3NO was necessary to produce [Ir4(CO)10{[Fe(eta5-P 3C2Bu t2)(eta5-C5H5)}] (4), obtained in the form of two non-interconverting isomers 4a and 4b, which were not able to be separated. A single crystal X-ray diffraction study of isomer 4a established that the [Fe(eta5-P3C2Bu t2)(eta5-C5H 5)] ligand bridges one of the edges of the Ir4 tetrahedron, interacting via the lone electron pair of one of the adjacent P atoms and in an eta²- mode via the P-P double bond of the eta5-P3C2Bu t 2 ring and that all CO ligands are terminally bonded. Variable temperature 31P{¹H} NMR spectroscopy evidenced a fluxional process involving interactions between the Ir1 and Ir2 atoms and the lone pair on P1, the P1-P2 bond, and the lone pair on P2. According to multinuclear NMR, cluster 4b has similar structure to compound 3, with the eta5-P3C2Bu t 2 ring co-ordinated in a eta¹-eta¹- mode via the two adjacent P atoms, and all CO ligands bonded terminally.

Reaction of [Ir4(mu-H)(CO)9(Ph2PCºCPh)(mu-PPh2)] 1 with PºCBu t in CH2Cl2, at 35 °C, for 4 h yields the novel compound [Ir4(mu-CO)(CO)7{mu4-eta³-Ph2PC(H)C(Ph)PCBu t}(mu-PPh2)] 2, which contains the 2-phosphabutadienylphosphine chain. Compound 2 is also formed upon thermolysis of [Ir4(CO)10(Ph2PCºCPh)(PPh2H)] 3 in the presence of PºCBu t in thf, at 40 °C, for 48 h. Small amounts of [Ir4(mu-CO)(CO)7(mu3-eta²-HCCPh)(mu-PPh2)2] 4 are always obtained from both reactions, because of the competing rates of the transformations of 1 and 3 into 4 and of their reactions with PºCBu t. Compound 2 was characterized by analytical and spectroscopic studies such as FAB ms, ¹H, 31P,13C, 2D31P-¹H HETCOR, nOe difference and DEPT NMR experiments, which led to its formulation and established the coupling between the coordinated Ph2PCºCPh and PºCBu t and the migration of the hydride to the Calpha of the Ph2PCºCPh ligand. However, it was impossible to establish unambiguously if cleavage of the P-Csp bond of the Ph2PCºCPh ligand had occurred and the mode of interaction of the organophosphorus chain. An X-ray diffraction study of compound 2 established a butterfly arrangement of iridium atoms with the new ligand interacting with the metal framework via four sigma bonds and the PPh2 phosphorus lone pair.