bluuebunny/crossref_metadata_2025 huggingface dataset:
Veränderung des selektiven Aufmerksamkeitsbias von Ängstlichkeit nach induzierter Rumination und Distraktion
Authors: Eßmann Ralf , de Jong-Meyer Renate
Published: May 2008

Zusammenfassung. Theoretischer Hintergrund: Ein selektiver Aufmerksamkeitsbias bei störungsbezogenen Reizen ist für Angststörungen nachgewiesen. In dieser Studie wird die Veränderbarkeit dieses Bias durch eine experimentelle Manipulation untersucht. Fragestellung: Es wird geprüft, ob die Induktion von Rumination versus Distraktion den Aufmerksamkeitsbias bei Ängstlichen beeinflusst und ob dieser Effekt unter Berücksichtigung von Ängstlichkeit und Depressivität spezifisch bei Stimuli mit Angstbezug auftritt. Methode: Nach Randomisierung in eine Ruminations- (N = 27) oder eine Distraktions-Induktion (N = 28) bearbeiteten 23 hochängstliche (BAI > 15) und 32 niedrigängstliche Personen eine emotionale Stroop-Aufgabe mit angstbezogenen, depressionsbezogenen und neutralen Worten. Depressivität, Ängstlichkeit, Stimmung sowie Dimensionen negativ selbstbezogenen Denkens wurden über Fragebogen erfasst. Ergebnisse: Die Induktionsbedingungen hatten den angenommenen differentiellen Einfluss auf die Stimmung (Verschlechterung unter Rumination). Nur die Ängstlichen zeigten nach Rumination einen stärkeren angstbezogenen Aufmerksamkeitsbias als unter Distraktion. Dieser Interaktionseffekt war spezifisch, da er sich bei depressionsbezogenen Worten nicht fand. Explorative Regressionsanalysen verwiesen auf habituelle Neigungen der Aufmerksamkeitsallokation als mögliche Determinanten des Aufmerksamkeitsbias. Schlussfolgerungen: Die Ergebnisse stützen Annahmen des von Williams und Kollegen (1997) formulierten Reizprioritätenmodells.
Psychometrische Überprüfung einer deutschsprachigen Fassung des Body Checking Questionnaire (BCQ)
Authors: Vocks Silja , Moswald Claudia , Legenbauer Tanja
Published: May 2008

Zusammenfassung. Theoretischer Hintergrund: Körperbezogenes Kontrollverhalten stellt die behaviorale Manifestation eines gestörten Körperbildes dar. Fragestellung: Eine deutschsprachige Version des „Body Checking Questionnaire” (BCQ) soll hinsichtlich ihrer psychometrischen Kennwerte überprüft werden. Methode: 124 Frauen mit und 202 Frauen ohne Essstörungen sowie 64 Männer beantworteten neben dem BCQ weitere Fragebögen zu Ess- und Körperbildstörungen. Ergebnisse: Faktorenanalysen legen eine Ein-Faktor-Lösung nahe. Es ergab sich eine hohe interne Konsistenz, Test-Retest-Reliabilität und Differenzierungsfähigkeit zwischen Frauen mit und ohne Essstörungen sowie gesunden Personen beiderlei Geschlechts. Hohe Korrelationskoeffizienten des BCQ mit den weiteren eingesetzten Fragebögen indizieren eine gute konvergente Validität. Ebenso zeigt der BCQ eine ausreichende Veränderungssensitivität. Schlussfolgerungen: Der BCQ ist ein reliables und valides Instrument, dessen Einsatz sich sowohl im Forschungs- als auch im Praxiskontext empfiehlt.
Interpersonelle Psychotherapie bei stationär behandelten, depressiven Patienten
Authors: Kech Sabine , Zobel Ingo , Dykierek Petra , van Calker Dietrich , Berger Mathias , Schramm Elisabeth
Published: May 2008

Zusammenfassung. Theoretischer Hintergrund: Eine erfolgreiche Depressionsbehandlung beinhaltet neben einer Remission depressiver Symptome, die Verbesserung der psychosozialen Leistungsfähigkeit. Fragestellung: Führt eine stationäre Behandlung mit Interpersoneller Psychotherapie in Kombination mit Medikation zu ausgeprägteren psychosozialen und interpersonellen Verbesserungen im Vergleich zu einer Standardbehandlung? Methode: 105 depressive Patienten, die auf „Interpersonelle Psychotherapie plus Pharmakotherapie” oder „Pharmakotherapie plus ärztliche Kurzgespräche” randomisiert wurden, wurden nach 5 Wochen stationärer Behandlung sowie 3 und 12 Monate nach Entlassung untersucht. Ergebnisse: In der klinischen Beurteilung der allgemeinen psychosozialen Leistungsfähigkeit erwies sich die Kombinationsbehandlung der Standardbehandlung signifikant überlegen, was allerdings über eine Verbesserung der Depressivität zu erklären war. In der Selbstbeurteilung der sozialen und interpersonellen Anpassung zeigten sich keine signifikanten Unterschiede. Schlussfolgerung: Zusätzliche Psychotherapie zeigt im Rahmen einer kurzfristigen stationären Depressionsbehandlung keine Vorteile hinsichtlich der sozialen und interpersonellen Anpassung gegenüber einer psychiatrischen Standardbehandlung.
Computerized Adaptive Testing of Personality Traits
Authors: Hol A. Michiel , Vorst Harrie C.M. , Mellenbergh Gideon J.
Published: May 2008

A computerized adaptive testing (CAT) procedure was simulated with ordinal polytomous personality data collected using a conventional paper-and-pencil testing format. An adapted Dutch version of the dominance scale of Gough and Heilbrun’s Adjective Check List (ACL) was used. This version contained Likert response scales with five categories. Item parameters were estimated using Samejima’s graded response model from the responses of 1,925 subjects. The CAT procedure was simulated using the responses of 1,517 other subjects. The value of the required standard error in the stopping rule of the CAT was manipulated. The relationship between CAT latent trait estimates and estimates based on all dominance items was studied. Additionally, the pattern of relationships between the CAT latent trait estimates and the other ACL scales was compared to that between latent trait estimates based on the entire item pool and the other ACL scales. The CAT procedure resulted in latent trait estimates qualitatively equivalent to latent trait estimates based on all items, while a substantial reduction of the number of used items could be realized (at the stopping rule of 0.4 about 33% of the 36 items was used).
ICAT: An Adaptive Testing Procedure for the Identification of Idiosyncratic Knowledge Patterns
Authors: Kingsbury G. Gage , Houser Ronald L.
Published: May 2008

Traditional adaptive tests provide an efficient method for estimating student achievements levels, by adjusting the characteristics of the test questions to match the performance of each student. These traditional adaptive tests are not designed to identify idiosyncratic knowledge patterns. As students move through their education, they learn content in any number of different ways related to their learning style and cognitive development. This may result in a student having different achievement levels from one content area to another within a domain of content. This study investigates whether such idiosyncratic knowledge patterns exist. It discusses the differences between idiosyncratic knowledge patterns and multidimensionality. Finally, it proposes an adaptive testing procedure that can be used to identify a student’s areas of strength and weakness more efficiently than current adaptive testing approaches. The findings of the study indicate that a fairly large number of students may have test results that are influenced by their idiosyncratic knowledge patterns. The findings suggest that these patterns persist across time for a large number of students, and that the differences in student performance between content areas within a subject domain are large enough to allow them to be useful in instruction. Given the existence of idiosyncratic patterns of knowledge, the proposed testing procedure may enable us to provide more useful information to teachers. It should also allow us to differentiate between idiosyncratic patterns or knowledge, and important mutidimensionality in the testing data.
Adaptive Measurement of Individual Change
Authors: Kim-Kang Gyenam , Weiss David J.
Published: May 2008

Adaptive measurement of change (AMC) was investigated by examining the recovery of true change. Monte Carlo simulation was used to compare three conventional testing (CT) methods with AMC. The CTs estimated individual change moderately well when the test was highly discriminating and when the θ level matched the test difficulty. However, AMC measured individual change equally well across the entire range of θ. AMC with more discriminating items produced the most precise estimates of individual change. AMC was shown to be superior to CTs under all conditions examined. In addition, AMC is efficient – it can dramatically reduce the number of items necessary to measure individual change. The results indicate that AMC is a viable and effective method for measuring individual change.
The Factor Structure and Validity of the Learning Styles Profiler (LSP)
Authors: O’Connor Peter J. , Jackson Chris J.
Published: May 2008

The Learning Styles Profiler (LSP; Jackson, 2002 ) is a modern measure of individual differences in learning style. The LSP is based on a neuropsychological model of learning, modeled on principles of approach and avoidance, and argues for the division of personality into temperament and character. There has been little research into the psychometric structure and predictive validity of this instrument. In Study 1, the factor structure of the LSP is examined, and in Study 2 the criterion-related validity of the LSP is assessed. Results support the proposed factor structure of the LSP and show that 3 of the 4 LSP scales are significant predictors of Job Performance.
Culture, Gender, and Assessment of Fear of Fatness
Authors: Ambwani Suman , Warren Cortney S. , Gleaves David H. , Cepeda-Benito Antonio , Fernandez Mari Carmen
Published: May 2008

To understand the relevance of the fear of fatness construct across culture and gender, we translated the Goldfarb Fear of Fat Scale (GFFS) and examined its psychometric properties in English and Spanish languages in a sample of Euro-American male (n = 111) and female (n = 100), and Spanish male (n = 114) and female (n = 544) college students in the United States and Spain. Confirmatory and exploratory analyses tested the measurement equivalence of the instrument across samples by gender and culture. Eight of the 10 items appeared to demonstrate measurement invariance. Mean comparisons on the eight-item version suggested that there was a gender by country interaction, with Euro-American women scoring substantially higher than the three other groups. Overall, these results highlight the need for additional examinations of cross-cultural instrument invariance and explorations of the fear of fatness construct.
Construction and Factorial Structure of a Short Version of the Trendsetting Questionnaire (TDS-K)
Authors: Batinic Bernad , Wolff Hans-Georg , Haupt Christiane M.
Published: May 2008

This paper reports the development of a short version of the trendsetting questionnaire (TDS; Batinic, Haupt, & Wieselhuber, 2006 ). According to Batinic et al., individuals high on trendsetting keep an eye open for new trends and have a broad interest in innovations. They inform a wide range of others and explain to them the value of innovations, and they recommend specific products to friends and acquaintances. Empirical criteria as well as substantive criteria were used to select nine items representing the three subtypes of the trendsetting model: input, throughput, and output. Dimensionality and measurement invariance of the short version (TDS-K) were examined in two offline surveys (N = 2,001 and 948) and two online surveys (N = 4,450 and 12,087). Multiple group confirmatory factor analyses supported the unidimensionality of the measure and showed that measurement invariance held within each of the administration methods (offline vs. online survey), but only partial invariance held across these methods.
The German EPP-D
Authors: Fischbach Andrea , Moosbrugger Helfried
Published: May 2008

In this study we evaluated a German version (EPP-D) of the Eysenck Personality Profiler (EPP). The EPP measures 21 traits, seven for each of Eysenck’s superfactors Extraversion, Emotionality (Neuroticism), and Adventure/Caution (Psychoticism). Each of these scales consists of 20 items with a trichotomous response scale (yes/can’t decide/no in the English original and yes/no/don’t know in the German translation). The 420-item questionnaire was completed by a sample including employees, university students, and high-school students (N = 2,006; mean age 31 years). The study applied three strategies: 1) abandoning the indifferent response category “don’t know,” 2) excluding missing values from the data analysis, which were coded equal to the indifferent response category, and 3) considering the results of item analyses including information on construct validity gained through confirmatory factor analyses (CFA). Findings from the EPP-D indicate that 155 items are sufficient to gain satisfactory psychometric properties of 15 primary scales (five traits each assigned to the superfactors). The EPP-D 155-item version has advantages in quality of data and administration time compared to the original EPP 420-item version.
Nitrogen isotope and trace metal analyses from the Mingolsheim core (Germany): Evidence for redox variations across the Triassic‐Jurassic boundary
Authors: Quan Tracy M. , van de Schootbrugge Bas , Field M. Paul , Rosenthal Yair , Falkowski Paul G.
Published: May 2008

The Triassic‐Jurassic (T‐J) boundary was one of the largest but least understood mass extinction events in the Phanerozoic. We measured bulk organic nitrogen and carbon isotopes and trace metal concentrations from a core near Mingolsheim (Germany) to infer paleoenvironmental conditions associated with this event. Poorly fossiliferous claystones across the boundary have relatively low δ15N values and low concentrations of redox‐sensitive elements, characteristic of an oxic environment with significant terrestrial input. The Early Jurassic features enrichment in δ15N coincident with high redox‐sensitive element concentrations, indicating an increase in water column denitrification and decreased oxygen concentrations. These redox state variations are concordant with shifts in abundance and species composition in terrestrial and marine microflora. We propose that the mass extinction at the T‐J boundary was caused by a series of events resulting in a long period of stratification, deep‐water hypoxia, and denitrification in this region of the Tethys Ocean basin.
The reconnection site of temporal cusp structures
Authors: Trattner K. J. , Fuselier S. A. , Petrinec S. M. , Yeoman T. K. , Escoubet C. P. , Reme H.
Published: May 2008

The strong precipitating particle flux in the cusp regions is the consequence of magnetic reconnection between the interplanetary magnetic field and the geomagnetic field. Magnetic reconnection is thought to be the dominant process for mass, energy, and momentum transfer from the magnetosheath into the magnetosphere. Observations of downward precipitating cusp ions by polar orbiting satellites are instrumental in unlocking many questions about magnetic reconnection, e.g., their spatial and temporal nature and the location of the reconnection site at the magnetopause. In this study we combine cusp observations of structures in the precipitating ion‐energy dispersion by the Cluster satellites with Super Dual Auroral Radar Network radar observations to distinguish between the temporal and spatial magnetic reconnection processes at the magnetopause. The location of the cusp structures relative to the convection cells is interpreted as a temporal phenomenon caused by a change in the reconnection rate at the magnetopause. The 3‐D plasma observations of the Cluster Ion Spectrometry instruments onboard the Cluster spacecraft also provide the means to estimate the location of the reconnection site. While an earlier study of a spatial cusp structure event revealed bifurcated reconnection locations in different hemispheres as origins for the precipitating ions creating the cusp structures, the same method applied to the temporal cusp structures in this study shows only a single tilted reconnection line close to the subsolar point. Tracing the distance to the reconnection site provides not only the location of the reconnection line but can also be used to distinguish between spatial and temporal cusp structures.
Global AIRS and MOPITT CO measurements: Validation, comparison, and links to biomass burning variations and carbon cycle
Authors: Yurganov Leonid N. , McMillan W. Wallace , Dzhola Anatoly V. , Grechko Evgeny I. , Jones Nicholas B. , van der Werf Guido R.
Published: May 2008

New results of CO global total column measurements using the Atmospheric Infrared Sounder (AIRS) aboard the Aqua satellite in comparison with Measurements of Pollution in the Troposphere (MOPITT) sensor aboard the Terra satellite are presented. Both data sets are validated using ground‐based total column measurements in Russia and Australia. A quality parameter based on the Profile Percent A Priori values from the standard MOPITT product is introduced. AIRS data (version 4) for biomass burning events are in agreement or lower than both MOPITT and ground measurements, but CO bursts can be seen by AIRS in most cases. For the cases of low CO amounts in the Southern Hemisphere AIRS has a positive bias of ∼30–40% compared to MOPITT and ground truth. MOPITT data were used to estimate interannual variations of CO sources assuming a standard seasonal cycle for the main CO remover OH. A positive trend of CO global emissions for the second half of the year between 2000 and 2006 was found with no visible trend for the first half of the year. CO annual emission in 2006 was 184 ± 40 Tg higher that that in 2000–2001. The monthly emission anomalies correlate well with an independently calculated Global Fire Emission Database (GFED2). Total carbon contribution from biomass burning in 1997, 1998 (both estimated by GFED2), and 2006 (according to MOPITT) were as high as (0.6–1) Pg C/year larger than in 2000, suggesting that fires can explain a substantial fraction of the interannual variability of CO2.
Computer simulation of the role of groundwater seepage in forming Martian valley networks
Authors: Luo Wei , Howard Alan D.
Published: May 2008

The role of groundwater in forming Martian valley networks is simulated in a computer model as seepage erosion by contributing to surface runoff and as seepage weathering by causing accelerated weathering of bedrock, which makes its subsequent erosion and removal easier. Simulation results show that seepage erosion cannot mobilize large grain size sediment and is marginally effective at generating integrated valley networks with realistic rates of aquifer recharge. On the other hand, seepage weathering may play a major role in forming Martian valley networks. Seepage weathering combined with fluvial runoff creates stubby deep canyons with abrupt headwalls that are similar in morphology to terrestrial and Martian valley systems attributed to erosion by groundwater. Depending on the relative contribution of groundwater weathering to surface runoff erosion, a continuum of valley network morphology can be generated. Eolian modification masks the original differences in fluvial landforms, making different scenarios visually more similar. Martian valley networks may have developed through a range of combinations of runoff erosion and seepage weathering, which can complicate the interpretation of the processes based on final landform morphology. Unequivocal identification of seepage involvement of valley incision on Mars may not be possible without knowledge of subsurface properties (hydraulic conductivity, layering, degree of cementation, etc.) and the grain sizes of sediment transported through the valley systems.
New Legislation Threatens the Teaching of Evolution
Authors: Landau Elizabeth
Published: May 2008

A new twist on an old legislative tactic may help open the door for the discussion of creationism and intelligent design in science classrooms across the United States. While previous attempts have been made to pass legislation regarding the teaching of evolution, new state legislation is being introduced with the purpose of affording “rights” and “protection” to teachers or students “concerning their positions on views regarding biological and chemical evolution,” according to the text from several bills. The proposed legislation would lessen the authority of written science curricula and potentially would allow legal protection for teachers or students to discuss nonscientific views of evolution in science classrooms.
2007 Outstanding Student Research Award for Mineral and Rock Physics to Kuwayama
Authors: Hirose Kei , Kuwayama Yasuhiro
Published: May 2008

Yasuhiro Kuwayama received the 2007 Mineral and Rock Physics Outstanding Student Research Award at the 2007 AGU Fall Meeting in San Francisco, Calif. The award recognizes one or more promising young scientists for outstanding contributions achieved during their Ph.D. research.
Nitric oxide-mediated modulation of calcium/calmodulin-dependent protein kinase II
Authors: Song Tao , Hatano Naoya , Kambe Toshie , Miyamoto Yoshiaki , Ihara Hideshi , Yamamoto Hideyuki , Sugimoto Katsuyoshi , Kume Kodai , Yamaguchi Fuminori , Tokuda Masaaki , Watanabe Yasuo
Published: May 2008

The mechanisms of NO inhibition of CaMK [Ca2+/CaM (calmodulin)-dependent protein kinase] II activity were studied. In rat pituitary tumour GH3 cells, TRH [thyrotrophin (TSH)-releasing hormone]-stimulated phosphorylation of nNOS [neuronal NOS (NO synthase)] at Ser847 was sensitive to an inhibitor of CaMKs, KN-93, and was enhanced by inhibition of nNOS with 7NI (7-nitroindazole). Enzyme activity of CaMKII following in situ treatment with 7NI was also increased. The in vitro activity of CaMKII was inhibited by co-incubation either with nNOS and L-arginine or with NO donors SNAP (S-nitroso-N-acetyl-DL-penicillamine) and DEA-NONOate [diethylamine-NONOate (diazeniumdiolate)]. Once inhibited by these treatments, CaMKII was observed to undergo full reactivation on the addition of a reducing reagent, DTT (dithiothreitol). In transfected cells expressing CaMKII and nNOS, treatment with the calcium ionophore A23187 further revealed nNOS phosphorylation at Ser847, which was enhanced by 7NI and CaMKII S-nitrosylation. Mutated CaMKII (C6A), in which Cys6 was substituted with an alanine residue, was refractory to 7NI-induced enhancement of nNOS phosphorylation or to CaMKII S-nitrosylation. Furthermore, we could identify Cys6 as a direct target for S-nitrosylation of CaMKII using MS. In addition, treatment with glutamate caused an increase in CaMKII S-nitrosylation in rat hippocampal slices. This glutamate-induced S-nitrosylation was blocked by 7NI. These results suggest that inactivation of CaMKII mediated by S-nitrosylation at Cys6 may contribute to NO-induced neurotoxicity in the brain.
The tumour suppressor PTEN mediates a negative regulation of the E3 ubiquitin-protein ligase Nedd4
Authors: Ahn Younghee , Hwang Chae Young , Lee Seung-Rock , Kwon Ki-Sun , Lee Cheolju
Published: May 2008

The tumour suppressor PTEN (phosphatase and tensin homologue deleted on chromosome 10; a phosphatidylinositol 3-phosphatase) is a multifunctional protein deregulated in many types of cancer. It is suggested that a number of proteins that relate with PTEN functionally or physically have not yet been found. In order to search for PTEN-interacting proteins that might be crucial in the regulation of PTEN, we exploited a proteomics-based approach. PTEN-expressing NIH 3T3 cell lysates were used in affinity chromatography and then analysed by LC–ESI–MS/MS (liquid chromatography–electrospray ionization–tandem MS). A total of 93 proteins were identified. Among the proteins identified, we concentrated on the E3 ubiquitin-protein ligase Nedd4 (neural-precursor-cell-expressed, developmentally down-regulated gene 4), and performed subsequent validation experiments using HeLa cells. Nedd4 inhibited PTEN-induced apoptotic cell death and, conversely, the Nedd4 level was down-regulated by PTEN. The down-regulation effect was diminished by a mutation (C124S) in the catalytic site of PTEN. Nedd4 expression was also decreased by a PI3K (phosphoinositide 3-kinase) inhibitor, LY294002, suggesting that the regulation is dependent on the phosphatase-kinase activity of the PTEN-PI3K/Akt pathway. Semi-quantitative real-time PCR analysis revealed that Nedd4 was transcriptionally regulated by PTEN. Thus our results have important implications regarding the roles of PTEN upon the E3 ubquitin ligase Nedd4 as a negative feedback regulator as well as a substrate.
Correctors promote folding of the CFTR in the endoplasmic reticulum
Authors: Loo Tip W. , Bartlett M. Claire , Clarke David M.
Published: May 2008

Cystic fibrosis (CF) is most commonly caused by deletion of a residue (ΔF508) in the CFTR (cystic fibrosis transmembrane conductance regulator) protein. The misfolded mutant protein is retained in the ER (endoplasmic reticulum) and is not trafficked to the cell surface (misprocessed mutant). Corrector molecules such as corr-2b or corr-4a are small molecules that increase the amount of functional CFTR at the cell surface. Correctors may function by stabilizing CFTR at the cell surface or by promoting folding in the ER. To test whether correctors promoted folding of CFTR in the ER, we constructed double-cysteine CFTR mutants that would be retained in the ER and only undergo cross-linking when the protein folds into a native structure. The mature form, but not the immature forms, of M348C(TM6)/T1142C(TM12) (where TM is transmembrane segment), T351C(TM6)/T1142C(TM12) and W356C(TM6)/W1145C(TM12) mutants were efficiently cross-linked. Mutations to the COPII (coatamer protein II) exit motif (Y563KDAD567) were then made in the cross-linkable cysteine mutants to prevent the mutant proteins from leaving the ER. Membranes were prepared from the mutants expressed in the absence or presence of correctors and subjected to disulfide cross-linking analysis. The presence of correctors promoted folding of the mutants as the efficiency of cross-linking increased from approx. 2–5% to 22–35%. The results suggest that correctors interact with CFTR in the ER to promote folding of the protein into a native structure.
Evidence for direct CFTR inhibition by CFTRinh-172 based on Arg347 mutagenesis
Authors: Caci Emanuela , Caputo Antonella , Hinzpeter Alexandre , Arous Nicole , Fanen Pascale , Sonawane Nitin , Verkman A. S. , Ravazzolo Roberto , Zegarra-Moran Olga , Galietta Luis J. V.
Published: May 2008

CFTR (cystic fibrosis transmembrane conductance regulator) is an epithelial Cl− channel inhibited with high affinity and selectivity by the thiazolidinone compound CFTRinh-172. In the present study, we provide evidence that CFTRinh-172 acts directly on the CFTR. We introduced mutations in amino acid residues of the sixth transmembrane helix of the CFTR protein, a domain that has an important role in the formation of the channel pore. Basic and hydrophilic amino acids at positions 334–352 were replaced with alanine residues and the sensitivity to CFTRinh-172 was assessed using functional assays. We found that an arginine-to-alanine change at position 347 reduced the inhibitory potency of CFTRinh-172 by 20–30-fold. Mutagenesis of Arg347 to other amino acids also decreased the inhibitory potency, with aspartate producing near total loss of CFTRinh-172 activity. The results of the present study provide evidence that CFTRinh-172 interacts directly with CFTR, and that Arg347 is important for the interaction.
Proximal mutations at the type 1 copper site of CotA laccase: spectroscopic, redox, kinetic and structural characterization of I494A and L386A mutants
Authors: Durão Paulo , Chen Zhenjia , Silva Catarina S. , Soares Cláudio M. , Pereira Manuela M. , Todorovic Smilja , Hildebrandt Peter , Bento Isabel , Lindley Peter F. , Martins Lígia O.
Published: May 2008

In the present study the CotA laccase from Bacillus subtilis has been mutated at two hydrophobic residues in the vicinity of the type 1 copper site. The mutation of Leu386 to an alanine residue appears to cause only very subtle alterations in the properties of the enzyme indicating minimal changes in the structure of the copper centres. However, the replacement of Ile494 by an alanine residue leads to significant changes in the enzyme. Thus the major visible absorption band is upshifted by 16 nm to 625 nm and exhibits an increased intensity, whereas the intensity of the shoulder at approx. 330 nm is decreased by a factor of two. Simulation of the EPR spectrum of the I494A mutant reveals differences in the type 1 as well as in the type 2 copper centre reflecting modifications of the geometry of these centres. The intensity weighted frequencies <νCu-S>, calculated from resonance Raman spectra are 410 cm−1 for the wild-type enzyme and 396 cm−1 for the I494A mutant, indicating an increase of the Cu–S bond length in the type 1 copper site of the mutant. Overall the data clearly indicate that the Ile494 mutation causes a major alteration of the structure near the type 1 copper site and this has been confirmed by X-ray crystallography. The crystal structure shows the presence of a fifth ligand, a solvent molecule, at the type 1 copper site leading to an approximate trigonal bipyramidal geometry. The redox potentials of the L386A and I494A mutants are shifted downwards by approx. 60 and 100 mV respectively. These changes correlate well with decreased catalytic efficiency of both mutants compared with the wild-type.
High Cu(I) and low proton affinities of the CXXC motif of Bacillus subtilis CopZ
Authors: Zhou Liang , Singleton Chloe , Le Brun Nick E.
Published: May 2008

CopZ, an Atx1-like copper chaperone from the bacterium Bacillus subtilis, functions as part of a complex cellular machinery for Cu(I) trafficking and detoxification, in which it interacts specifically with the transmembrane Cu(I)-transporter CopA. Here we demonstrate that the cysteine residues of the MXCXXC Cu(I)-binding motif of CopZ have low proton affinities, with both exhibiting pKa values of 6 or below. Chelator competition experiments demonstrated that the protein binds Cu(I) with extremely high affinity, with a small but significant pH-dependence over the range pH 6.5–8.0. From these data, a pH-corrected formation constant, β2=∼6×1022 M−2, was determined. Rapid exchange of Cu(I) between CopZ and the Cu(I)-chelator BCS (bathocuproine disulfonate) indicated that the mechanism of exchange does not involve simple dissociation of Cu(I) from CopZ (or BCS), but instead proceeds via the formation of a transient Cu(I)-mediated protein–chelator complex. Such a mechanism has similarities to the Cu(I)-exchange pathway that occurs between components of copper-trafficking pathways.
Relationship between age and measures of balance, strength and gait: linear and non-linear analyses
Authors: El Haber Natalie , Erbas Bircan , Hill Keith D. , Wark John D.
Published: May 2008

An age-related decline in balance, gait and lower-extremity muscle strength measures may lead to increased risk of falls and fractures. Previous studies have reported a possible non-linear age-related decline in these measures, but the choice of methodological approach has limited its interpretation. Healthy community-dwelling women (n=212) 21–82 years of age were evaluated for strength [Nicholas MMT (manual muscle tester)], gait [CSA (clinical stride analyser)], activity [HAP (human activity profile)] and static and dynamic balance [CBS (Chattecx balance system), LBT (Lord's balance test) and the ST (step test)]. A GAM (generalized additive model) was developed for each outcome variable to estimate the functional relationship, with age as a continuous variable. Performance was maintained until 45–55 years of age, depending on the outcome measure. Thereafter a decline in performance was evident with increasing age in all measures. Overall, a significant non-linear relationship with age was demonstrated for lower-extremity strength measures (MMT), velocity and double support duration of gait (CSA) and some clinical and laboratory balance tests [ST, LBT (eyes open) and the CBS]. Linear relationships were demonstrated by the LBT with eyes closed and activity measures. Balance, lower-extremity muscle strength and gait may decline non-linearly with age. Our study suggests possible threshold effects between age and balance, muscle strength and gait measures in women. Further research into these threshold effects may have implications for the optimal timing of exercise and other interventions to reduce the risk of falls and fractures.
A functional intronic variant in the tyrosine hydroxylase (TH) gene confers risk of essential hypertension in the Northern Chinese Han population
Authors: Wang Laiyuan , Li Biao , Lu Xiangfeng , Zhao Qi , Li Yun , Ge Dongliang , Li Hongfan , Zhang Penghua , Chen Shufeng , Chen Runsheng , Qiang Boqin , Gu Dongfeng
Published: May 2008

The TH (tyrosine hydroxylase) gene encodes the rate-limiting enzyme of catecholamine biosynthesis, and is involved in the pathogenesis of hypertension, but the relationship of its variants with hypertension has not been extensively studied. We designed a case-controlled study consisting of 503 HT (hypertensive) individuals and 490 NT (normotensive) individuals matched by region, age and gender to systematically investigate the association between the TH gene and hypertension. Based on the HapMap and dbSNP (where SNP is single nucleotide polymorphism) data, four SNPs, rs6356 A>G, rs6357 G>A, rs2070762 T>C and rs1800033 A>G in the TH gene were selected for genotyping. Rs1800033 was not polymorphic in our study population. No significant differences were observed for distributions of rs6356 and rs6357 between the HT and NT groups. However, both the genotype and allele frequencies of rs2070762 showed significant differences between cases and controls (P<0.001 and P=0.005 respectively). In haplotype analysis, a total of eight haplotypes were observed in the entire population and the overall frequency distributions differed significantly between the HT and NT groups. Specifically, haplotype A-A-C (rs6356-rs6357-rs2070762) occurred only in the HT group and A-G-C occurred more commonly in HT subjects than in NT subjects (P=0.003 and P=0.013 respectively). Compared with the most common haplotype A-G-T, the adjusted OR (odds ratio) was 1.83 [95% CI (confidence interval), 1.20–2.79; P=0.0049] for haplotype G-G-C and 20 (P<0.0001) for the haplotype A-A-C. Functional analysis showed that the C allele of rs2070762 functioned as an enhancer in the absence of binding by unidentified transcriptional repressor(s). These results provide evidence for an association of the functional intronic rs2070762 with essential hypertension.
HIV-positive patients treated with protease inhibitors have vascular changes resembling those observed in atherosclerotic cardiovascular disease
Authors: Lekakis John , Tsiodras Sotirios , Ikonomidis Ignatios , Palios John , Poulakou Garyfalia , Rallidis Loukianos , Antoniadou Anastasia , Panagopoulos Periklis , Papadopoulos Antonios , Giamarellou Helen , Kremastinos Dimitrios T.
Published: May 2008

A metabolic syndrome associated with atherosclerosis and cardiovascular disease has been described in HIV-positive individuals. In the present study we investigated whether HIV-positive individuals and CAD (coronary artery disease) patients have similarities in their vascular function and structure. In a case-control study, we compared measurements of carotid artery IMT (intima-media thickness) and brachial artery FMD (flow-mediated vasodilation) in HIV-positive individuals with age- and sex-matched controls with similar risk factors and patients with established CAD. Seventy-one HIV patients, age 42±13.9 years (91% male), were compared with 29 CAD patients and 25 controls. HIV patients had higher IMT than controls and similar IMT to CAD patients (0.64±0.2 compared with 0.55±0.05 and 0.66±0.08 mm respectively; F=4.2, P=0.01). Patients taking protease inhibitors had higher IMT (0.69±0.2 compared with 0.57±0.15 mm; P=0.01), blood pressure, cholesterol and triacylglycerols than those not taking protease inhibtors (P<0.05). In multiple regression analyses, increasing blood pressure (β: 0.37, P=0.001), glucose (β: 0.26, P=0.016), cholesterol (β: 0.24, P=0.033), duration of HIV disease (β: 0.33, P=0.008) and use of protease inhibitors (β: 0.27, P=0.04) were the most important determinants of IMT respectively. FMD was associated only with triacylglycerol measurements. Patients with HIV present arterial changes resembling those found in patients with atherosclerotic cardiovascular disease. These vascular changes are closely related to protease-inhibitor-induced changes of metabolic parameters. Thus intensive treatment of these metabolic parameters might retard atherosclerosis in HIV patients.
Haem oxygenase-1 gene transfer protects retinal ganglion cells from ischaemia/reperfusion injury
Authors: Peng Pai-Huei , Ko Mei-Lan , Chen Chau-Fong , Juan Shu-Hui
Published: May 2008

RGC (retinal ganglion cell) death following ischaemic insult is the major cause of a number of vision-threatening diseases, including glaucoma. The aim of the present study was to evaluate the role of HO-1 (haem oxygenase-1) in the retina against IR (ischaemia/reperfusion) injury. Adenovirus-mediated HO-1 gene transfer (Adv-HO-1) was carried out by injection into the vitreous body to induce HO-1 overexpression. At 3 weeks after transfection, levels of HO-1 expression, as measured by Western blot analysis, immunohistochemical staining and activity assay, were drastically up-regulated. Transient retinal ischaemia was induced by raising the intraocular pressure to 150 mmHg for 60 min. Untreated IR caused a significant decrease in RGC numbers at 3 and 7 days after reperfusion (76.1 and 67.2% of control eyes with sham IR respectively; P<0.001). Eyes pretreated with Adv-HO-1 had less RGC loss on day 3 and 7 following reperfusion compared with control eyes injected with Adv-GFP (adenovirus containing a gene for green fluorescent protein; 94.3 and 88.2% respectively; P=0.007 and 0.001). SnP (tin protoporphyrin), an HO-1 inhibitor, counteracted the effects of Adv-HO-1. In conclusion, these findings provide evidence that augmentation of HO-1 enzyme overexpression by intravitreal injection is able to protect RGCs against IR-induced damage.
Increased plasma urotensin-II levels are associated with diabetic retinopathy and carotid atherosclerosis in Type 2 diabetes
Authors: Suguro Toshiaki , Watanabe Takuya , Kodate Syuusuke , Xu Gang , Hirano Tsutomu , Adachi Mitsuru , Miyazaki Akira
Published: May 2008

Human U-II (urotensin-II), the most potent vasoconstrictor peptide identified to date, is associated with cardiovascular disease. A single nucleotide polymorphism (S89N) in the gene encoding U-II (UTS2) is associated with the onset of Type 2 diabetes and insulin resistance in the Japanese population. In the present study, we have demonstrated a relationship between plasma U-II levels and the progression of diabetic retinopathy and vascular complications in patients with Type 2 diabetes. Eye fundus, IMT (intima-media thickness) and plaque score in the carotid artery, BP (blood pressure), FPG (fasting plasma glucose), HbA1c (glycated haemoglobin), U-II, angiogenesis-stimulating factors, such as VEGF (vascular endothelial growth factor) and heregulin-β1, and lipid profiles were determined in 64 patients with Type 2 diabetes and 24 non-diabetic controls. FPG, HbA1c and VEGF levels were significantly higher in patients with Type 2 diabetes than in non-diabetic controls. Diabetes duration, insufficient glycaemic and BP control, plasma U-II levels, IMT, plaque score and nephropathy grade increased significantly across the subjects as follows: non-diabetic controls, patients with Type 2 diabetes without retinopathy (group N), patients with Type 2 diabetes with simple (background) retinopathy (group A) and patients with Type 2 diabetes with pre-proliferative and proliferative retinopathy (group B). The prevalence of obesity and smoking, age, low-density lipoprotein, triacylglycerols (triglycerides) and heregulin-β1 were not significantly different among the four groups. In all subjects, U-II levels were significantly positively correlated with IMT, FPG, and systolic and diastolic BP. Multiple logistic regression analysis revealed that, of the above parameters, U-II levels alone had a significantly independent association with diabetic retinopathy. In conclusion, the results of the present study provide the first evidence that increased plasma U-II levels may be associated with the progression of diabetic retinopathy and carotid atherosclerosis in patients with Type 2 diabetes.
Real Estate Advertising and Intraurban Place Meaning: Real Estate Sales Consultants at Work
Authors: Perkins Harvey C , Thorns David C , Newton Bronwyn M
Published: May 2008

We examine the mediating role of real estate agency in the residential housing market with reference to intraurban place meaning. Our focus is on real estate advertising because it is the central mediating technique used by sales consultants to incorporate and extend the market activities of a range of actors whose interests and needs are intertwined in the interpretation and representation of people's houses and homes, and those parts of the city in which they are located. We therefore discuss the process of making and deploying such advertising and the ways real estate sales consultants help continually to reinvigorate the meaning of suburbs and other urban localities.
Social Networks, Mobility Biographies, and Travel: Survey Challenges
Authors: Axhausen K W
Published: May 2008

Social network membership and biography shape a person's mental map and social network geography, and thus should influence his or her travel behaviour. This paper discusses what content needs to be added to the current set of questions asked in travel behaviour surveys if we want to capture those concepts. The discussion proceeds conceptually, as there is little empirical work so far on which to draw. The challenges involved in integrating the necessary questions about biographies and social networks are considerable. The protocols will have to rely on more personal contact between the survey and the respondent, either by phone or in person.
The Role of Discourse Coalitions in Planning for Renewable Energy: A Case Study of Wind-Energy Deployment
Authors: Mander Sarah
Published: May 2008

This paper explores the role of coalition building in the implementation of renewable-energy policy. Applying a discourse analysis framework to wind-energy development in the North West of England, two strong coalitions operating within the wind-energy development arena were identified. By combining this framework with a multicriteria assessment, it is revealed that each coalition had very different priorities during the evaluation of wind-energy schemes. Overall, only when offshore wind is evaluated are there elements of common ground. This technology therefore appears to offer a solution to sharp contrasts in discourse. Based on this assessment, it is concluded that the implementation of national energy-policy objectives is contingent upon the regional government developing coherent storylines to attract the support of as broad a coalition of stakeholders as possible.
Social Multicriteria Evaluation of Conflict over Rural Electrification and Solar Energy in Spain
Authors: Munda Giuseppe , Russi Daniela
Published: May 2008

A case study is presented with two objectives: (i) to give a clear and simple illustration of social multicriteria evaluation in the field of rural renewable-energy policy, and (ii) to help in understanding the extent to which, and the circumstances under which, solar energy is suitable for electrifying isolated farmhouses. Our aim is to provide public decision makers with insight into the conditions that favour the diffusion of renewable energy. This should facilitate the design of more effective energy policies for rural communities.
Moving Methods, Travelling Times
Authors: Watts Laura , Urry John
Published: May 2008

In this paper, we consider the passenger experience of travel time, and its translation into a transport model of travel time, which is of great significance in the potential funding and construction of infrastructural projects. In the economic appraisals of such projects, which are often of massive scale and impact, it is presumed that travel time is wasted, dead, or empty, and therefore should be minimised. However, in this paper we show how travel time is filled with activities and fantasies. We show that there are multiple travel times and places, and not just a single measured clock time that has to be minimised in getting from point A to point B. Travel time is situated in the sociomaterial practices of travel, which include engaging with other passengers, interacting with wireless networks, views out of the window, things packed in one's bag, and so on. We describe and evaluate various ‘moving methods’ for researching places on-the-move, from survey to ethnography. Finally, we consider how to disrupt the assumption in transport appraisal that such time is empty and should be minimised, and suggest new approaches for presencing the richness of passenger travel time in transport modelling.
The Attenuation Effect in Timing: Counteracting Dual-Task Interference with Time-Judgment Skill Training
Authors: Brown Scott W
Published: May 2008

A basic finding in the time-perception literature is an interference effect in dual-task conditions involving concurrent timing and distractor tasks. Dual-task conditions typically cause time judgments to become less accurate than single-task conditions in which subjects judge time alone. Previous research (Brown, 1998 Psychological Research61 71–81; Brown and Bennett, 2002 Psychological Research66 80–89) has shown that practice on the distractor task reduces interference, a phenomenon called the attenuation effect. The present research was designed to determine whether practice on the time-judgment task would produce a similar result. In experiment 1, subjects reproduced 6–14 s intervals in a series of practice trials. Some subjects received feedback regarding the accuracy of each response and others received no feedback. Subsequent testing under dual-task (timing + digit memory) conditions showed that feedback training reduced interference. In experiment 2, the practice trials included both single-task and dual-task conditions. Later tests showed that feedback training eliminated the interference effect. The results highlight the role of attentional resources, the transfer of skills, and compensatory decision processes in time-judgment skill training.
Interferon signaling and treatment outcome in chronic hepatitis C
Authors: Sarasin-Filipowicz Magdalena , Oakeley Edward J. , Duong Francois H. T. , Christen Verena , Terracciano Luigi , Filipowicz Witold , Heim Markus H.
Published: May 2008

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease worldwide. The current standard therapy for chronic hepatitis C (CHC) consists of a combination of pegylated IFN alpha (pegIFNα) and ribavirin. It achieves a sustained viral clearance in only 50–60% of patients. To learn more about molecular mechanisms underlying treatment failure, we investigated IFN-induced signaling in paired liver biopsies collected from CHC patients before and after administration of pegIFNα. In patients with a rapid virological response to treatment, pegIFNα induced a strong up-regulation of IFN-stimulated genes (ISGs). As shown previously, nonresponders had high expression levels of ISGs before therapy. Analysis of posttreatment biopsies of these patients revealed that pegIFNα did not induce expression of ISGs above the pretreatment levels. In accordance with ISG expression data, phosphorylation, DNA binding, and nuclear localization of STAT1 indicated that the IFN signaling pathway in nonresponsive patients is preactivated and refractory to further stimulation. Some features characteristic of nonresponders were more accentuated in patients infected with HCV genotypes 1 and 4 compared with genotypes 2 and 3, providing a possible explanation for the poor response of the former group to therapy. Taken together with previous findings, our data support the concept that activation of the endogenous IFN system in CHC not only is ineffective in clearing the infection but also may impede the response to therapy, most likely by inducing a refractory state of the IFN signaling pathway.