Characterizing executive functioning in older special populations: From cognitively elite to cognitively impaired.

The authors examined the structure and invariance of executive functions (EF) across (a) a continuum of cognitive status in 3 groups of older adults (cognitively elite [CE], cognitively normal [CN], and cognitively impaired [CI]) and (b) a 3-year longitudinal interval. Using latent variable analyses (LISREL 8.80), the authors tested 3-factor models (“Inhibition”: Hayling [Burgess & Shallice, 1997], Stroop [Regard, 1981]; “Shifting”: Brixton [Burgess & Shallice, 1997], Color Trails [D’Elia et al., 1996]; and “Updating”: Reading and Computational Span [Salthouse & Babcock, 1991]) and 1-factor models within each group. Participants (initial N = 570; 53–90 years) were from the Victoria Longitudinal Study (Sample 3, Waves 1 and 2). Cross-sectionally, the authors observed a 3-factor EF structure especially for the CE group and 1-factor solutions for all 3 groups. Longitudinally, temporal invariance was supported for the 3-factor model (CE and CN groups) and the 1-factor model (CI and CN groups). Subgroups with higher cognitive status and greater 3-year stability performed better on EF factors than corresponding groups with lower cognitive status and less stability. Studies of EF structure, performance, dedifferentiation, and dysfunction will benefit from considering initial cognitive status and longitudinal stability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A conceptual model of riparian forest restoration for natural flood management

There is an increasing emphasis on using natural processes, including riparian forest restoration, to enhance the ecological, hydrological and geomorphological functioning of watercourses. However, we have insufficient knowledge on how the supply and retention of in‐channel wood from riparian forest stands changes with age, with inferences typically based on data from terrestrial forests. This presents a challenge in estimating the efficacy and functional lifespan of restoration projects. In this paper, we use a riparian forest growth model to show there is a lag of up to 40–50 years between the start of forest growth and trees delivering wood to the channel that is large enough to resist fluvial transport, anchor logjams and so increase channel complexity and hydraulic resistance. Resource managers need to account for realistic timescales over which changes promoted by riparian woodland restoration will occur and may need to consider using interim engineered logjams as the forest develops.     

Glycoalkaloid Concentrations in Aerial Tubers of Potato ( Solanum tuberosumL)

The total glycoalkaloid concentrations in aerial and subterranean tubers of 14 potato genotypes were measured using high-performance liquid chromatography immediately after harvest. Post-harvest, aerial tubers from all genotypes were exposed to 144 h continuous fluorescent light; additionally three genotypes (cvs Home Guard, Kerrs Pink and Desiree) were subjected to mechanical wounding prior to glycoalkaloid analysis. Variations in glycoalkaloid concentrations between aerial tubers taken from a single genotype (cv Kerrs Pink) were determined by analysis of eight aerial tubers formed in the second leaf axil, selected from separate individual plants. Irrespective of genotype, total and individual glycoalkaloid concentrations were higher in aerial than in subterranean tubers. The highest glycoalkaloid concentrations were found in aerial tubers of cv Kerrs Pink (1343·0 mg kg⁻¹ FW) and lowest in cv Lindsey (301·0 mg kg⁻¹ FW). Ratios of α-chaconine: α-solanine in aerial tubers differed significantly ( P< 0·05) from those in subterranean tubers of cv Cara, Golden Wonder, Home Guard, Lindsey, Maris Piper, Record and 8859 indicating that exposure to light during aerial tuber growth enhanced the synthesis of one glycoalkaloid to a greater degree than the other. In all cultivars except cv Maris Piper, exposure of aerial tubers to 144 h continuous fluorescent light post-harvest increased total and individual glycoalkaloids compared with dark-treated controls. However, the ratios of α-chaconine: α-solanine in all genotypes except cv Golden Wonder (decreased α-chaconine: α-solanine, P< 0·05) were not significantly altered in comparison with dark controls, indicating that light exposure of aerial tubers post-harvest fails to enhance selectively synthesis of individual glycoalkaloids in the majority of cultivars. Regardless of cultivar, total glycoalkaloid, α-solanine and α-chaconine concentrations were higher in wounded than unwounded aerial tubers. Wounding stimulated synthesis of α-solanine more than α-chaconine ( P< 0·05) in cv Home Guard and Desiree. Glycoalkaloid concentrations in aerial tubers varied widely from a minimum of 1010 mg kg⁻¹ to a maximum of 2520 mg kg⁻¹ FW when harvested from individual plants of cv Kerrs Pink but selected from equivalent positions on the plant. Throughout the experiments large, non-significant increases in total and individual glycoalkaloid concentrations were recorded following light and wounding treatments. The scientific implications of aerial tuber formation are discussed.     

Effect of particle shape on methanol partial oxidation in a fixed bed using CFD reactor modeling

Particle shape is one of the most important parameters in the design and optimization of fixed-bed processes. To address the impact of particle shape on methanol partial oxidation to formaldehyde over molybdate catalyst, packings of spheres, cylinders, rings, and trilobes are numerically generated. The generated packings are used to carry out resolved particle Computational Fluid Dynamics (CFD) simulations under industrial conditions. Pressure drop, voidage and velocity profiles, radial heat transfer, and local and overall conversion and selectivity results are presented. Despite their lower particle surface area, lower particle effectiveness and more uneven flow distribution than trilobes, and lower overall heat transfer coefficient than cylinders, rings had the best conversion and selectivity due to their balance between the factors. Three longer tubes of rings, rings and cylinders, and rings and trilobes are simulated and show a small gain in selectivity for the rings and trilobes.     

Development of a Gene-Activated Scaffold Incorporating Multifunctional Cell-Penetrating Peptides for pSDF-1α Delivery for Enhanced Angiogenesis in Tissue Engineering Applications

Non-viral gene delivery has become a popular approach in tissue engineering, as it permits the transient delivery of a therapeutic gene, in order to stimulate tissue repair. However, the efficacy of non-viral delivery vectors remains an issue. Our lab has created gene-activated scaffolds by incorporating various non-viral delivery vectors, including the glycosaminoglycan-binding enhanced transduction (GET) peptide into collagen-based scaffolds with proven osteogenic potential. A modification to the GET peptide (FLR) by substitution of arginine residues with histidine (FLH) has been designed to enhance plasmid DNA (pDNA) delivery. In this study, we complexed pDNA with combinations of FLR and FLH peptides, termed GET* nanoparticles. We sought to enhance our gene-activated scaffold platform by incorporating GET* nanoparticles into collagen–nanohydroxyapatite scaffolds with proven osteogenic capacity. GET* N/P 8 was shown to be the most effective formulation for delivery to MSCs in 2D. Furthermore, GET* N/P 8 nanoparticles incorporated into collagen–nanohydroxyapatite (coll–nHA) scaffolds at a 1:1 ratio of collagen:nanohydroxyapatite was shown to be the optimal gene-activated scaffold. pDNA encoding stromal-derived factor 1α (pSDF-1α), an angiogenic chemokine which plays a role in BMP mediated differentiation of MSCs, was then delivered to MSCs using our optimised gene-activated scaffold platform, with the aim of significantly increasing angiogenesis as an important precursor to bone repair. The GET* N/P 8 coll–nHA scaffolds successfully delivered pSDF-1α to MSCs, resulting in a significant, sustained increase in SDF-1α protein production and an enhanced angiogenic effect, a key precursor in the early stages of bone repair.     

Veteran interest in family involvement in PTSD treatment.

[Correction Notice: An erratum for this article was reported in Vol 7(3) of Psychological Services (see record 2010-17074-004). The copyright for the article was listed incorrectly. This article is in the Public Domain. The online version has been corrected.] The present study examined interest in family involvement in treatment and preferences concerning the focus of family oriented treatment for veterans (N = 114) participating in an outpatient Veterans Affairs outpatient posttraumatic stress disorder (PTSD) program. Most veterans viewed PTSD as a source of family stress (86%) and expressed interest in greater family involvement in their treatment (79%). These results suggest the need to consider increasing family participation in the clinical care of individuals with PTSD and to develop specialized family educational and support services for this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of enzyme systems and processing on the hydrolysis of peanut (Arachis hypogaea L.) protein

In vitro protein digestion studies were carried out on raw and roasted peanut flour as the starting material in the production of peanut protein hydrolysate. Peanut flour was hydrolyzed with alcalase and alternately in a sequential digestion with pepsin-pancreatin, both for up to 24 h. The degree of hydrolysis (DH) at different times of hydrolysis was determined using the trinitrobenzenesulfonic acid (TNBS) method. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to indicate destruction of native protein units in the enzymatic digests.Hydrolysis with alcalase was very rapid for the first 6 h after which a plateau was reached, whereas that with pepsin–pancreatin was more gradual reaching a plateau after 12 h of hydrolysis. Raw peanut hydrolyzed with alcalase and pepsin–pancreatin had 23% and 21% DH after 24 h respectively, whilst roasted peanut hydrolyzed with alcalase had 21% DH, with the pepsin–pancreatin hydrolysate recording the highest value of 25% after 24 h of hydrolysis.SDS-PAGE results showed that raw peanut samples behaved differently from the roasted samples; increasing hydrolysis time reduced larger peanut protein subunits, with only peptides of <20 kDa visible after hydrolysis for raw peanut, and virtually no distinct visible bands for the roasted peanut after 3 h of hydrolysis.     

Viscous Lubrication in Wire Drawing

A scheme for the promotion of viscous lubrication in wire drawing is analyzed. Lubricant pressure is built up by means of close tolerance tube installed in front of the die. In the die, plasticity is maintained by the combination of fluid pressure and wire tension. In the analysis presented here the lubricant flow rate and film thickness variation in the die are solved for as well as the necessary length of pressure tube. Pressure and temperature effects on the lubricant viscosity and strain hardening effects on the wire metal are included in the analysis.     

Serotonin 5-HT2 receptors in schizophrenia: a PET study using [18F]setoperone in neuroleptic-naive patients and normal subjects

BACKGROUND: In the FRISC trial, dalteparin 120 IU/kg body weight twice daily for unstable coronary artery disease was safe and reduced the risk of new coronary events. This risk reduction was maintained during the following extended treatment with a fixed dose of 7500 IU dalteparin once daily. METHODS AND RESULTS: Minor bleeding was more frequent in women compared with men: relative risk (CI) 2.88 (1.78 to 4.67) during the weight-adjusted and 2.36 (1.37 to 2.63) during the fixed dose treatment. The anti-Xa activity determined in samples (n = 175) obtained during the acute phase treatment was higher in women compared with men (P <.001) and in nonsmokers compared with smokers (<.001) in multiple regression analysis. Also, during the fixed-dose treatment (n = 131) an independent relation between anti-Xa activity and sex (P <.001), but not smoking habits, persisted. CONCLUSION: To improve future low-molecular-weight heparin dose regimens for the treatment of acute coronary syndromes, it might be important to consider the influence of sex and smoking habits.