Phonemic awareness and letter knowledge in the child's acquisition of the alphabetic principle.

Studied acquisition of the alphabetic principle in preliterate children, 3–5 yrs. The dependent variable throughout was a forced-choice between, e.g., "mow" and "sow" as pronunciations for the written word mow after the child had been taught to read the words mat and sat. Reliable performance on this transfer task was only achieved by children who (a) understood two aspects of phonological organization—phonemic segmentation of the speech items and the identity of their initial segments, and (b) had learned graphic symbols for the sounds "m" and "s." Most children who demonstrated alphabetic insight with symbols in word-initial position were also successful at transfer when the symbols were word-final. Thus, phonemic awareness and grapheme-phoneme knowledge were needed in combination for acquisition of the alphabetic principle, and, once gained, alphabetic insight proved relatively robust. Implications for reading acquisition are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hydroxyapatite bone substitutes developed via replication of natural marine sponges

The application of synthetic cancellous bone has been shown to be highly successful when its architecture mimics that of the naturally interconnected trabeculae bone it aims to replace. The following investigation demonstrates the potential use of marine sponges as precursors in the production of ceramic based tissue engineered bone scaffolds. Three species of natural sponge, Dalmata Fina (Spongia officinalis Linnaeus, Adriatic Sea), Fina Silk (Spongia zimocca, Mediterranean) and Elephant Ear (Spongia agaricina, Caribbean) were selected for replication. A high solid content (80 %wt), low viscosity (126 mPas) hydroxyapatite slurry was developed, infiltrated into each sponge species and subsequently sintered, producing a scaffold structure that replicated pore architecture and interconnectivity of the precursor sponge. The most promising of the ceramic tissue engineered bone scaffolds developed, Spongia agaricina replicas, demonstrated an overall porosity of 56–61% with 83% of the pores ranging between 100 and 500 μm (average pore size 349 μm) and an interconnectivity of 99.92%.     

Reliability of adult retrospective recall of lifetime tobacco use.

Retrospective assessment of tobacco use underlies much of the data collected in epidemiological and genetic epidemiological research. Although individuals are asked to report lifetime tobacco use for periods spanning months to decades, the test-retest reliability intervals of the instruments often span only a few weeks to several months. The present analyses examined the test-retest reliability of retrospective tobacco use measures, including details of first use, circumstances of first use, and initial subjective reactions. The questions were part of the Lifetime Tobacco Use Questionnaire (LTUQ), a Web-based questionnaire designed to assess use of most forms of tobacco or nicotine retrospectively across the lifespan. A convenience sample of 236 men and women with history of tobacco use (Time 1 mean age, 44.9 years; 74.2% females; 75.1% regular monthly tobacco use) responded verifiably to invitations to self-administer the LTUQ two times, 2 years apart. Test-retest reliability analyses reflected high reliability for salient tobacco-use questions. Acceptable levels of reliability were observed for initial subjective reactions to smoking, if the scaled response options were dichotomized. Few differences in the reliability of recall were apparent between sexes and between age groups. These results indicate that recall of important tobacco use information can form a reliable basis for research.     

A proposed structural model for amyloid fibril elongation: domain swapping forms an interdigitating {beta}-structure polymer

We propose a model illustrating how proteins, which differ intheir overall sequences and structures, can form the propagating,twisted ß-sheet conformations, characteristic of amyloids.Some cases of amyloid formation can be explained through a `domainswapping' event, where the swapped segment is either a ß-hairpinor an unstable conformation which can partially unfold and assumea ß-hairpin structure. As in domain swapping, herethe swapped ß-hairpin is at the edge of the structure,has few (if any) salt bridges and hydrogen bonds connectingit to the remainder of the structure and variable extents ofburied non-polar surface areas. Additionally, in both casesthe swapped piece constitutes a transient `building block' ofthe structure, with a high population time. Whereas in domainswapping the swapped fragment has been shown to be an     

Asian-American acculturation, severity of concerns, and willingness to see a counselor.

Asian Americans at a major West Coast university were surveyed to determine how severe each of 24 problems was for them and to assess their willingness to see a counselor for each problem. Factor analysis reduced the 24 problems to 8 areas of concern. A repeated measures analysis of variance (ANOVA) revealed that severity ratings for the 8 concerns were related to acculturation and ethnicity. With severity ratings as covariates, a repeated measures analysis of covariance (ANCOVA) was computed for willingness to see a counselor ratings. Willingness to see a counselor was found to be related to both acculturation and gender across all 8 concerns. Women expressed greater willingness to see the counselor than did men and low-medium acculturated students expressed greater willingness to see a counselor than did high-acculturated students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

myo-Inositol trispyrophosphate: a novel allosteric effector of hemoglobin with high permeation selectivity across the red blood cell plasma membrane

myo‐Inositol trispyrophosphate (ITPP), a novel membrane‐permeant allosteric effector of hemoglobin (Hb), enhances the regulated oxygen release capacity of red blood cells, thus counteracting the effects of hypoxia in diseases such as cancer and cardiovascular ailments. ITPP‐induced shifting of the oxygen–hemoglobin equilibrium curve in red blood cells (RBCs) was inhibited by DIDS and NAP‐taurine, indicating that band 3 protein, an anion transporter mainly localized on the RBC membrane, allows ITPP entry into RBCs. The maximum intracellular concentration of ITPP, determined by ion chromatography, was 5.5×10^?3 M , whereas a drop in concentration to the limit of detection was observed in NAP‐taurine‐treated RBCs. The dissociation constant of ITPP binding to RBC ghosts was found to be 1.72×10^?5 M . All data obtained indicate that ITPP uptake is mediated by band 3 protein and is thus highly tissue‐selective towards RBCs, a feature of major importance for its potential therapeutic use.     

Cell‐Selective,Apoptosis‐inducing Rhodium(III) Crown Thiaether Complexes

Half‐sandwich rhodium(III) polypyridyl (pp) complexes with the metal atom capped by the facial crown thiaether 1,4,7‐trithiacyclononane [9]aneS₃ represent a promising class of apoptosis‐inducing potent cytostatic agents. The necrotic damage caused by the complexes is negligible. In vitro cytotoxicity assays with the human cancer cell lines MCF‐7 and HT‐29 and immortalized HEK‐293 cells indicate that the dicationic κ²N(imino) complexes [([9]aneS₃)RhCl(pp)]²⁺ are much more active than monocationic complexes [([9]aneS₃)RhCl₂(L)]⁺ (L=imidazole, CH₃CN). Whereas the κ²N(amino) complex [([9]aneS₃)RhCl(piperazine)]²⁺ is inactive, replacing piperazine with the structurally analogous κ²S (thiaether) ligand 1,4‐dithiane restores cytotoxicity as evidenced by IC₅₀ values in the range 8.1‐11.6 μM . Spectroscopic (CD, UV/Vis, NOESY) and viscosity measurements indicate that the active dppz complex 8 (IC₅₀ values: 4.7–8.9 μM ) exhibits strong intercalative binding towards DNA whereas the even more potent bipyrimidine complex 9 (IC₅₀ values: 0.6–1.9 μM ) causes no alteration of the duplex B conformation. Weaker intercalative binding is observed for the dpq complex 7 . A comparative annexin V–propidium iodide binding assay with lymphoma (BJAB) cells and healthy leukocytes demonstrates that the cytotoxic activity of complex 8 and particularly complex 9 is highly selective towards the malignant cells.     

Effect of natural oils on the thermal stability and degradation kinetics of recycled polypropylene wood flour composites

Recycled polypropylene was reinforced with wood fibers that were non‐treated and treated with different natural oils (hexanoic, octanoic, decanoic and dodecanoic acids). The thermal properties, morphology, kinetics and thermodynamic parameters were investigated. The use of natural oils as coupling agents clearly improved the interfacial adhesion with the matrix and increased the thermal stability of the composites. Octanoic acid improved the thermal stability of the composite the most compared with the other evaluated natural oils. The improvement caused by this natural oil is similar to that promoted by the addition of PPgMA. The thermal stability of the composite was affected by the boiling temperature and the chain length of the acid used. POLYM. COMPOS., 35:1935–1942, 2014. © 2014 Society of Plastics Engineers