A Prospective Study of Adolescents' Peer Support: Gender Differences and the Influence of Parental Relationships

This longitudinal study investigates parent and child predictors of adolescents' perceived social support from peers. Adolescents (285) and their parents filled out surveys when students were 11 and 15 years of age. Parent reports of their own social support and child reports of parental support to them, depression, and self-esteem were used as predictors of adolescents' peer social support. Path analyses revealed functional dissimilarity in the predictive model, for boys and girls. For boys and girls, the amount of spousal support parents' reported impacted the amount of parent to child support that children reported. For boys, this relationship impacted their perceptions of peer support indirectly through depression. However, for girls, parents' own supportive relationships directly impacted both their self-esteem and depression, above and beyond parent to child support, which then impacted girls' peer social support.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45288/1/10964_2004_Article_229992.pd

An evaluation of seed spacing accuracy of a vacuum type precision metering unit based on theoretical considerations and experiments [Teorik ve deneysel verilere dayali{dotless} olarak vakumlu tek dane ekim ünitesinin tohum arali{dotless}gi{dotless} düzgünlügünün degerlendirilmesi]

Currently the most widely used machine for precision seeding of cotton and maize seed is vacuum type. The capture of seeds by vacuum plate and the release of seeds from the vacuum plate should be performed precisely without missing or doubling. The physical phenomena should be clarified theoretically to understand how the precision seeding mechanism works. To solve these problems, an attempt was made to develop a nomogram using equations describing the technical characteristics of the seeder used in this study and to describe the seed capture mechanism relying on basic principles of fluid mechanics and aerodynamic properties of seeds. Seed spacing accuracy tests were performed to test the theory on a sticky belt in the laboratory. Quality of feed index, miss and multiple indices, and precision have been taken as a set of criteria for seed spacing accuracy. The regression models developed using the data obtained via sticky band tests showed that 16 seeds s-1 was the upper limit of seed release frequency (SRF) for cotton and maize seeds. The upper limit of vacuum plate peripheral speed was found to be 0.34 m s-1. The use of 72 holes instead of 26 holes in the vacuum plate at 6.3 kPa created a vacuum band in the width of 10 mm around holes and this increased the multiple index and caused a reduction in seeding performance. For this reason, the use of vacuum plates with 60 or 52 holes is recommended for cotton seed. The forward speed of either 1.0 or 1.5 m s-1 was found to be acceptable for the seed spacing of 0.05 and 0.10 m, respectively. Aerodynamic calculations verified that widely used vacuum plates with 26 holes were the appropriate ones for seeding maize seeds. The performance indices, namely the quality of feed, and miss and multiple indices, reduced significantly for cotton and maize seeding when the precision metering unit was run at 20% (11°) slope to the right as compared to the no slope condition. © TÜBİTAK

Optimization of the seed spacing uniformity performance of a precision seeder using spherical materials and response surface methodology

The objective of this study was to optimize the seed spacing uniformity performance of a precision seeder using spherical materials and Response Surface Methodology (RSM) and to verify the optimum levels of the variables. The variables considered in the study included vacuum on seed plate, the diameter of seed holes and peripheral speed of the seed plate. Spherical materials made of plastic were used and experiments based on Central Composite Design (CCD), one of the designs in RSM were carried out in the laboratory. The data obtained were divided into three different groups in order to obtain the values of Multiple Index, Quality of Feed Index, Miss Index. Other performance indicators called root mean square deviation and CP3 were also calculated and evaluated in the study. Prediction functions mostly for quality of feed index in polynomial form allowed the calculation of the optimum level of each independent variable. Optimum levels of the variables obtained for each spherical material were tested and verified

Synthesis, characterization and properties of tetra((l-hydroxyimino- methylnaphthalen-2-yloxy)methyl)etheneandits homo-dinuclear metal complexes: A combined experimental and theoretical investigation

Tetra((l-hydroxyiminomethylnaphthalen-2-yloxy)methyl)ethene (THlMNYOME), H4L, was synthesized by the agents of 2-hydroxy-l -naphtaldehyde, tetra(bromomethyl)ethene and hydroxylamine hydrochloride in two steps. Characterization of THIMNYOME and its dinuclear complexes was made by elemental analyses, IR, 1H- and 13C NMR, UV-vis, electrospray ionisation mass spectra, molar conductivities and magnetic susceptibility measurements. In the light of these results, it was suggested that the ligand coordinate to each metal atom by the two ether oxygen, two nitrogen atoms of oxime (C-N) and an axial oxygen of Perchlorate to form pseudo square-pyramidal complexes with Ni(II), Cu(Il) and Zn(II). Molar conductivity measurements reveal that all the complexes are non-electrolytes. In addition, the full geometric optimization of the tetraoxime ligand (4) has been made by the B3LYP/6-31G(d) level in order to establish a stable conformation. Additionally, all the complex structures have been studied in the B3LYP/LANL2DZ level. NBO charge distribution and the characteristics of frontier molecular orbitais of these complexes have also been investigated in order to see the electrons movement between ligand and metal atom in the same level. © 2010 Elsevier B.V. All rights reserved

Two novel macroacyclic schiff bases containing bis-N2O2 donor set and their binuclear complexes: synthesis, spectroscopic and magnetic properties

Herein, we report two novel macroacyclic Schiff bases derived from tetranaphthaldehyde derivative compound and their binuclear Mn(II), Ni(II), Cu(II) and Zn(II) complexes. The structures of the compounds have been proposed by elemental analyses, spectroscopic data i.e. IR, 1H and 13C NMR, UV-Vis, electrospray ionisation mass spectra, molar conductivities and magnetic susceptibility measurements. The stoichiometries of the complexes derived from mass and elemental analysis correspond to the general formula [M2L(ClO4)n](ClO4)4-n, (where M is Mn(II), Ni(II), Cu(II), Zn(II) and L represents the Schiff base ligands). © 2009 Elsevier B.V. All rights reserved.Türkiye Bilimsel ve Teknolojik Araştirma Kurumu 107T383This work was supported by the Scientific and Technical Research Council of Turkey (TUBITAK) under project No. 107T383

The relationships between uric acid levels and insulin resistance, body fat distribution and cardiovascular risk factors in obese subjects

Abstract Not Availabl

The comparison of anthropometric measurements in determining total body fat and the body fat distribution

Abstract Not Availabl

Synthesis, characterization, spectral and electrical properties of peripherally tetratriazole-substituted phthalocyanines and its metal complexes

The substituted [1,2,4]triazole 3 was obtained from the reaction between compound 1 and compound 2. Novel substituted phthalonitrile 5 was prepared by the substitution of the nitro group of 4-nitrophthalonitrile 4 with triazole moiety 3. The synthesis of metal-free, zinc, nickel, cobalt and copper phthalocyanines with four substituted [1,2,4]triazole groups on peripheral position were performed from cyclotetramerization of novel substituted dinitrile compound 5. Metal-free phthalocyanine 6 and its Zn-, Ni-, Co- and Cu- complexes 7-10 were prepared in DMAE at reflux temperature. All new compounds were characterized by a combination of elemental analyses, IR, 1H/ 13C NMR, MS and UV-vis spectroscopy. Aggregation behaviors of NiPc 8 and CuPc 10 were also investigated. While NiPc 8 was aggregated in acetone, DMF, DMSO, THF, ethylacetate and toluene and non-aggregated in dichloromethane and pyridine at 10 × 10 -6 mol dm -3 concentration, CuPc 10 showed monomeric behavior in dichloromethane, DMSO, DMF, pyridine, THF and showed aggregation in acetone, ethylacetate and toluene at 14 × 10 -6 mol dm -3 concentration. On the other hand, substituted NiPc 8 and CuPc 10 did not show aggregation behavior between 4 × 10 -6-14 × 10 -6 mol dm -3 concentration range in chloroform. Dc and ac conductivity and Impedance Spectroscopy (IS) studies were also done on thin films of compounds 6, 7, 8, 9 and 10 as a function of temperature (295-523 K) and frequency (40-10 5 Hz) under vacuum (?2 × 10 -3 mbar) in dark. The compounds 7, 8, 9 and 10 showed nearly same dc conductivity values in the measured temperature range. Variation of dc conductivity of 6, 7, 8, 9 and 10 with temperature exhibited the semiconducting behavior. Variation of ac conductivity of the films with frequency represented by the function ? ac = A? s. The results indicated that charge transport mechanism of the films can be explained by hopping and small polaron tunneling model for 6, 7, 8, 9 and 10 depending on temperature and frequency region. Results of the impedance spectra measurements showed that, at high temperatures, depressed semicircles with different radius indicate deviation from Debye dispersion relation. © 2012 Elsevier B.V. All rights reserved.Karadeniz Teknik Üniversitesi: 2010.111.002.3The Authors thank to The Research Fund of Karadeniz Technical University, Project No: 2010.111.002.3 (Trabzon/Turkey)