bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of ultrasound on maternal‐fetal bonding: a comparison of two‐ and three‐dimensional imaging
Authors: Ji E.‐K. , Pretorius D. H. , Newton R. , Uyan K. , Hull A. D. , Hollenbach K. , Nelson T. R.
Published: April 2005

Objectives

The purpose of this study was to evaluate the effect of two‐dimensional (2DUS) compared to three‐dimensional ultrasound (3DUS) imaging on the maternal‐fetal bonding process.

Methods

Fifty mothers who had 2DUS and 50 who had 2DUS and 3DUS were included in the study. A postpartum survey by telephone interview was carried out to assess maternal‐fetal bonding. Bonding was evaluated by analysis of extent of prenatal image sharing, maternal ability to form a mental picture of the baby and mother's comments about their ultrasound images. Data were analyzed using the independent t‐test, Chi‐square and Mann–Whitney U‐tests.

Results

Mothers who received 3DUS showed their ultrasound images to more people (median, 27.5; interquartile range, 14.5–40.0) than mothers receiving 2DUS alone (median, 11.0; interquartile range, 5.0–25.5) (P < 0.001, Z = −3.539). Eighty‐two percent of the subjects screened with 3DUS had a greater tendency to form a mental picture of the baby postexamination compared to 39% of the 2DUS subjects (P < 0.001, Z = −3.614). Mothers receiving a 3DUS study were more likely to receive comments on the similarities/differences of the neonate compared to those having 2DUS studies. Furthermore, 70% of the mothers receiving 3DUS felt they ‘knew’ the baby immediately after birth vs. 56% of the mothers receiving 2DUS (P = 0.009, Z = −2.613). Both 2DUS and 3DUS experiences were positive, however, the comments made by the mothers undergoing 3DUS (n = 18) were more exclamatory (amazed, wonderful, fabulous) than those undergoing 2DUS (n = 4). Patients having a 3DUS examination consistently scored higher than those having a 2DUS examination alone for all categories of maternal‐fetal bonding.

Conclusion

3DUS appears to more positively influence the perceptions of mothers to their babies postbirth compared to 2DUS. Specifically, mothers who had 3DUS showed their ultrasound images to a greater number of people compared to mothers who had 2DUS alone and this may represent mother's social support system. 3DUS may have a greater impact on the maternal‐fetal bonding process. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Isolation and sequence analysis of the gene URA3 encoding the orotidine‐5′‐phosphate decarboxylase from Candida glycerinogenes WL2002‐5, an industrial glycerol producer
Authors: Li Yanli , Shen Wei , Wang Zhengxiang , Liu Ji‐Quan , Rao Zhiming , Tang Xueming , Fang Huiying , Zhuge Jian
Published: April 2005

The URA3 gene of Candida glycerinogenes WL2002‐5, an industrial glycerol producer encoding orotidine‐5′‐phosphate decarboxylase enzyme, was isolated by complementation cloning in Saccharomyces cerevisiae. DNA sequence analysis revealed the presence of an open reading frame (ORF) of 786 bp, encoding a 262 amino acid protein, which shares 71.65% amino acid sequence similarity to the S. cerevisiae URA3 protein. Furthermore, the cloned ORF fully complemented the ura3 mutation of S. cerevisiae, confirming that it encodes for the C. glycerinogenes Ura3 (CgUra3) protein. The GenBank Accession No. for CgUra3 is AY623794. Copyright © 2005 John Wiley & Sons, Ltd.
Evaluation of the Saccharomyces cerevisiae ADH2 promoter for protein synthesis
Authors: Michael Lee K. , DaSilva Nancy A.
Published: April 2005

The Saccharomyces cerevisiae ADH2 promoter (PADH2) is repressed several hundred‐fold in the presence of glucose; transcription is initiated once the glucose in the medium is exhausted. The promoter can thus be utilized for effective regulation of recombinant gene expression in S. cerevisiae without the addition of an inducer. To evaluate this promoter in the absence of plasmid copy number and stability variations, the PADH2 − lacZ cassette was integrated into the yeast chromosomes. The effects of medium composition, glucose concentration and cultivation time on promoter derepression and expression level were investigated. Maximum protein activity was obtained after 48 h of growth in complex YPD medium containing 1% glucose. The widely used S. cerevisiae GAL1 and CUP1 promoters both require the addition of an inducer [galactose and copper(II) ion, respectively] before regulated genes will be expressed. The strengths of these three different promoters were compared for cells containing one copy of an integrated lacZ gene under their control. The ADH2 promoter was superior for all induction strategies investigated. Copyright © 2005 John Wiley & Sons, Ltd.
Molecular cloning and biochemical characterization of a 3′(2′),5′‐bisphosphate nucleotidase from Debaryomyces hansenii
Authors: Aggarwal Monika , Bansal Parmil K. , Mondal Alok K.
Published: April 2005

The enzyme 3′(2′),5′‐bisphosphate nucleotidase catalyses a reaction that converts 3′‐phosphoadenosine‐5′‐phosphate (PAP) to adenosine‐5′‐phosphate (AMP) and inorganic phosphate (Pi). The enzyme from Saccharomyces cerevisiae is highly sensitive to sodium and lithium and is thus considered to be the in vivo target of salt toxicity in yeast. In S. cerevisiae, the HAL2 gene encodes this enzyme. We have cloned a homologous gene, DHAL2, from the halotolerant yeast Debaryomyces hansenii. DNA sequencing of this clone revealed a 1260 bp open reading frame (ORF) that putatively encoded a protein of 420 amino acid residues. S. cerevisiae transformed with DHAL2 gene displayed higher halotolerance. Biochemical studies showed that recombinant Dhal2p could efficiently utilize PAP (Km17 µM) and PAPS (Km48 µM) as substrate. Moreover, we present evidence that, in comparison to other homologues from yeast, Dhal2p displays significantly higher resistance towards lithium and sodium ions. The nucleotide sequence of DHAL2 gene has been submitted to Genbank (Accession No. AY340817). Copyright © 2005 John Wiley & Sons, Ltd.
TOR kinase pathway and 14‐3‐3 proteins regulate glucose‐induced expression of HXT1, a yeast low‐affinity glucose transporter
Authors: Tomás‐Cobos Lidia , Viana Rosa , Sanz Pascual
Published: April 2005

Expression of HXT1, a gene encoding a Saccharomyces cerevisiae low‐affinity glucose transporter, is regulated by glucose availability, being activated in the presence of glucose and inhibited when the levels of the sugar are scarce. In this study we show that 14‐3‐3 proteins are involved in the regulation of the expression of HXT1 by glucose. We also demonstrate that 14‐3‐3 proteins, in complex with Reg1, a regulatory subunit of Glc7 protein phosphatase, interact physically with Grr1 (a component of the SCF–Grr1 ubiquitination complex), a key player in the process of HXT1 induction by glucose. In addition, we show that the TOR kinase pathway participates actively in the induction of HXT1 expression by glucose. Inhibition of the TOR kinase pathway by rapamycin treatment abolishes HXT1 glucose induction. A possible involvement of PP2A protein phosphatase complex, through the Cdc55 B‐subunit, in the glucose induction of HXT1 is also discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Cloning and heterologous expression of the NADPH cytochrome P450 oxidoreductase genes from an industrial dicarboxylic acid‐producing Candida tropicalis
Authors: He Feng , Chen Yuan Tong
Published: April 2005

NADPH cytochrome P450 oxidoreductase (CPR) catalyses the transfer of electrons during P450‐mediated oxidation, which plays an important role in the ω‐oxidation pathway of Candida tropicalis. Two putative allelic genes, CPR‐a and CPR‐b, were cloned from the long chain dicarboxylic acid‐producing Candida tropicalis 1230, using cassette PCR methods. Both the identified open reading frames predict the gene products of 679 amino acid residues. The deduced amino acid sequences of CPR‐a and CPR‐b are highly homologous to CPR genes from C. tropicalis ATCC 750 and Candida maltosa. Both genes were individually expressed in a cpr mutant of Saccharomyces cerevisiae with high CPR activities, in which only a small distinction was observed between recombinant CPR‐a and CPR‐b. Both CPR‐a and CPR‐b contain one CTG codon, which codes for serine (amino acid 50) in C. tropicalis rather than universal leucine. A mutated cDNA of CPR‐a with a TCG codon instead of CTG codon was constructed and expressed, resulting in little increase in CPR activity. This indicates that the alteration of Ser‐50 has little effect on functional expression of CPR. Furthermore, high ketoconazole sensitivity for the cpr mutant was complemented by heterologous expression of the cloned CPR‐a or CPR‐b. The sequences of CPR‐a and CPR‐b have been submitted to DDBJ/EMBL/GeneBank databases under Accession Nos AY705446 and AY823228, respectively. Copyright © 2005 John Wiley & Sons, Ltd.
The inhibitory mechanism of curcumin and its derivative against β‐catenin/Tcf signaling
Authors: Park Chi Hoon , Hahm Eun Ryeong , Park Seyeon , Kim Hyun-Kyung , Yang Chul Hak
Published: April 2005

We investigated the inhibitory mechanism of curcumin and its derivative (CHC007) against β‐catenin/T‐cell factor (Tcf) signaling in various cancer cell lines. Curcumin is known to inhibit β‐catenin/Tcf transcriptional activity in HCT116 cells but not in SW620 cells. To clarify the inhibitory effect of curcumin against β‐catenin/Tcf signaling, we tested several cancer cell lines. In addition, in order to verify the inhibitory mechanism, we performed reporter gene assay, Western blot, immunoprecipitation, and electrophoretic mobility shift assay. Since inhibitors downregulated the transcriptional activity of β‐catenin/Tcf in HEK293 cells transiently transfected with S33Y mutant β‐catenin gene, whose product is not induced to be degraded by adenomatous polyposis coli–Axin–glycogen synthase kinase 3β complex, we concluded that the inhibitory mechanism was related to β‐catenin itself or downstream components. Western blot analysis suggested that no change in the amount of cytosolic and membranous β‐catenin in a cell occurred; however, nuclear β‐catenin and Tcf‐4 proteins were markedly reduced by inhibitors and this lead to the diminished association of β‐catenin with Tcf‐4 and to the reduced binding to the consensus DNA. In the present study, we demonstrate that curcumin and its derivative are excellent inhibitors of β‐catenin/Tcf signaling in all tested cancer cell lines and the reduced β‐catenin/Tcf transcriptional activity is due to the decreased nuclear β‐catenin and Tcf‐4.
The acoustic target strength of herring (Clupea harengus L.) in the northern Baltic Sea
Authors: Peltonen Heikki , Balk Helge
Published: April 2005

The hydro-acoustic target strength (TS) of herring (Clupea harengus L.) was estimated from the catch composition of 19 pelagic-trawl hauls and from simultaneous recordings with a split-beam, 38 kHz echosounder. The data were collected in September 2000 during a Bothnian Sea survey in the northern Baltic Sea. The dependence of TS (in dB) on fish length (L, cm) was modelled with the equation TS = a log10 L + b. The fitted model was TS = 16.8 log10 L − 60.0. With a predefined slope of 20 the TS vs. log-fish length relationship was TS = 20 log10 L − 63.9. The analyses suggested that TS was higher in the Bothnian Sea than is assumed in most studies in the Baltic Sea. Applying the revised TS–length dependence considerably enhanced the agreement between the biomass estimates from hydroacoustics and those from a catche-at-age analysis (VPA).
Damage mechanisms and failure modes of cortical bone under components of physiological loading
Authors: George W. T. , Vashishth D.
Published: April 2005

Fatigue damage development in cortical bone was investigated in vitro under different mechanical components of physiological loading including tension, compression, and torsion. During each test, stress and strain data were collected continuously to monitor and statistically determine the occurrence of the primary, secondary, and tertiary stages associated with fatigue and/or creep failure of bone. The resultant microdamage and failure modes were identified by histological and fractographic analysis, respectively. The tensile group demonstrated Mode I cracking and the three classic stages of fatigue and creep suggesting a low crack initiation threshold, steady crack propagation and final failure by coalescence of microcracks. In contrast, the compressive group displayed Mode II cracking and a two‐stage fatigue behavior with limited creep suggesting a high crack initiation threshold followed by a sudden fracture. The torsion group also displayed a two‐stage fatigue profile but demonstrated extensive damage from mixed mode (Modes II and III) microcracking and predominant time‐dependant damage. Thus, fatigue behavior of bone was found to be uniquely related to the individual mechanical components of physiological loading and the latter determined the specific damage mechanisms associated with fatigue fracture. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
IBZM-SPECT imaging of dopamine D2 receptors with typical and atypical antipsychotics
Authors: Kasper S , Tauscher J , Küfferle E , Hesselmann B , Barnas C , Brücke T
Published: April 2005

Considerable progress has been achieved over the past 15 years in uncovering the biological basis of major psychiatric disorders. Since psychopharmacological treatment is thought tc act on the underlying biological basis of the disease, brain imaging techniques enable us to understand the mechanism of action of such compounds. One important tool used to determine patterns of brain dysfunction and how psychopharmacological agents such as antipsychotic compounds work is single-photon emission computerised tomography (SPECT). This technique allows determination of striatal D2 receptor occupancy rates, which are associated with the extrapyramidal side effects (EPS) of antipsychotic drugs. Studies have confirmed that atypical antipsychotic agents have lower occupancy rates than typical agents. No association has been found between D2 receptor occupancy rates n the striatum and antipsychotic efficacy, and it therefore appears that striatal D2 receptor occupancy rates are not necessary for the antipsychotic effect of such agents in schizophrenia. The availability of more refined radioligands will help us not only to understand the action of antipsychotics but also the pathophysiology of schizophrenia.
Measuring the economic benefit of treatment with atypical antipsychotics
Authors: Knapp MRJ
Published: April 2005

Schizophrenia has a major impact on the quality of life of sufferers, and its broader impact on families and on society are well known, although less thoroughly documented. The majority of sufferers require long-term treatment and support, and there are depressingly frequent media stories about violent incidents involving people with the illness. Consequently the costs of schizophrenia, broadly defined, loom large, not just from the perspective of health care decision-makers and governments, but also from that of sufferers and their families, to many other people with only indirect experience of the disease.
Normative angiographic data relating to the dimensions of the aorta and pulmonary trunk in children and adolescents
Authors: Rammos Spyridon , Apostolopoulou Sotiria C. , Kramer Hans H. , Kozlik-Feldmann Reiner , Heusch Andreas , Laskari Cleo V. , Anagnostopoulos Constantine
Published: April 2005

Background:Definition of normative data of the great arteries from neonatal to adult ages may aid in assessment of the growth of cardiovascular structures, thus guiding the timing and type of intervention in patients with congenital cardiac disease.Methods:We calculated the cross-sectional areas of the arterial roots at the basal attachment of the valvar leaflets, the sinuses, and standardized distal sites using cineangiograms of 59 normal children and adolescents with mean age of 5.4 plus or minus 4.7 years and a range from 0.1 to 16 years, the children having a mean weight of 21.2 plus or minus 15.7 kilograms, with a range from 2.2 to 68 kilograms, and mean height of 108 plus or minus 35 centimetres, with a range from 43 to 184 centimetres. Values at each site were calculated averaging end-diastolic and end-systolic measurements, and indexed to body surface area. Results are expressed as the mean plus or minus the standard deviation.Results:The diameter of the aortic root at the basal attachment of the leaflets was 249 plus or minus 26, the midpoint of the sinuses 379 plus or minus 59, the sinutubular junction 290 plus or minus 58, the isthmus 158 plus or minus 36, the postisthmic region 152 plus or minus 33, and the descending aorta at the level of diaphragm 130 plus or minus 18 millimetres squared per metre squared. The pulmonary root measured at the basal attachment of the leaflets was 253 plus or minus 28, the midpoint of the sinuses 352 plus or minus 58, the sinutubular junction 293 plus or minus 58, the right pulmonary artery 176 plus or minus 25, the left pulmonary artery 153 plus or minus 20, and sum of right and left pulmonary arteries 330 plus or minus 37 millimetres squared per metre squared. All indexes were consistent over a wide range for body surface areas.Conclusions:Definition of normative data of the great vessels may aid in the evaluation of congenital or acquired abnormalities, serving as guidelines for intervention during medical or surgical management and follow-up.
Comparison of segmental and global systemic ventricular function at rest and during dobutamine stress between patients with transposition and congenitally corrected transposition
Authors: van der Zedde Janna , Oosterhof Thomas , Tulevski Igor I. , Vliegen Hubert W. , Mulder Barbara J. M.
Published: April 2005

The aim of the study was to evaluate segmental and global right ventricular function at rest and during stress in patients having a systemic morphologically right ventricle. We studied 17 patients after atrial correction for transposition, 13 with congenitally corrected transposition, and 11 age-matched controls using cardiovascular magnetic resonance at rest and during stress with dobutamine given at 15 micrograms per kilogram per minute. Blood was drawn to obtain levels of brain natriuretic peptide. Right ventricular ejection fraction was calculated, and wall-motion and wall-thickening were assessed, in 4 segments of a midventricular slice. The findings for the systemic right ventricle were compared to the left ventricle in controls. Patients with transposition showed a decreased ejection fraction at rest (57 percent versus 69 percent, p equal to 0.005), decreased wall motion of the anterior, lateral and septal wall (p less than 0.01, p less than 0.01, and p less than 0.01) and decreased thickening of the lateral wall (p less than 0.01). Patients with congenitally corrected transposition showed normal ejection fraction, wall thickening, and wall motion at rest. During dobutamine stress, we found no significant differences in wall motion and thickening between the two groups. Ejection fraction, also increased to comparable values during stress, at 67 percent versus 66 percent, p not being significant. In both groups, we observed similarly increased levels of brain natriuretic peptide (p equal to 0.02 and 0.03, respectively). We conclude that only patients with transposition showed segmental wall motion and wall thickening abnormalities at rest. After dobutamine stress, however, segmental and global right ventricular dysfunction was similar in both groups.
Non-invasive assessment of right ventricular function in the late follow-up of the Senning procedure
Authors: Morhy Samira S. , Andrade Jose L. , Soares Andressa M. , Ribeiro Zilma V. , Wilberg Tatiana M. , Mathias Wilson , Parga Jose R. , Bustamante Luis N. P. , Atik Edmar , Ramires Jose F.
Published: April 2005

Deteriorating ventricular function is a major concern after the Senning operation. A Doppler-derived non-geometric measurement, the so-called myocardial performance index, has been described for use in adults and children. We aimed to assess the utility of this index as a method for quantification of right ventricular function in patients in the late follow-up of the Senning procedure, and to correlate the right ventricular ejection fraction and the first derivative of right ventricular pressure as derived using echocardiography with the ejection fraction determined using magnetic resonance imaging.

We studied 44 patients within a mean postoperative period of 15.3 years. We calculated the right ventricular myocardial performance index by pulsed wave Doppler interrogation of tricuspid inflow and aortic outflow, the ejection fraction by Simpson's rule, and the first derivative of right ventricular pressure by continuous wave Doppler from tricuspid regurgitation.

Mean values of right ventricular myocardial performance index, ejection fraction, and the first derivative of right ventricular pressure were 0.50, 39 percent and 1,398 millimetres of mercury per second, respectively. A cut-off value of 0.47 for the right ventricle myocardial performance index was determined, with a sensitivity of 75 percent and a specificity of 62.5 percent. We found no correlation between ejection fraction and the first derivative of right ventricular pressure as estimated by echocardiography and the ejection fraction as shown by magnetic resonance imaging (r2 equal to 0.29 and 0.04 respectively).

We concluded, first, that patients with preserved right ventricular function had values for the right ventricular myocardial performance index lower than 0.47, and second, that ejection fraction and the first derivative of right ventricular pressure as determined echocardiographically did not correlate with values derived using magnetic resonance imaging.
Myocardial ischaemia in a child infected with influenza B
Authors: Grosse-Wortmann Lars , Muehler Eberhard G.
Published: April 2005

Cardiac involvement is a rare complication of infection by the influenza B virus. It usually presents with ventricular dysfunction, arrhythmias, or both. We report a 13-year-old boy with clinical, electrocardiographic, and laboratory findings of myocardial ischaemia during an otherwise silent acute infection with influenza B. Coronary endothelial injury constituted a potential underlying mechanism, and microthrombosis was promoted by high levels of lipoprotein(a) in the serum.
Duplication of the 22q11.2 region associated with congenital cardiac disease
Authors: Sparkes Rebecca , Chernos Judy , Dicke Franciscus
Published: April 2005

The DiGeorge, or velocardiofacial, syndrome has been aetiologically linked to heterozygous deletion of the q11.2 region of chromosome 22. It is the most common of the microdeletion syndromes, and is associated with malformations involving the ventricular outflow tracts. Duplication of the 22q11.2 region has also been reported, adding to a growing list of syndromes involving genomic deletion or duplication that cause disease by decreasing or increasing the gene dosage. We report two cases of congenital cardiac disease associated with microduplications of 22q11.2, and discuss the evidence to date for the potential clinical significance of this genetic defect.
Feldman, Analysis, Experience
Authors: HANNINEN DORA A.
Published: April 2005

The growing number of performances and recordings of Feldman’s music in recent years attests to increased interest among performers and listeners; yet his music remains an uncommon subject for detailed music analysis. Proceeding on the premise that this disparity is no accident, I argue that certain distinctive qualities of the music render it difficult to analyse with tools, methods, and practices developed in response to other repertories. This paper investigates the analytical challenges posed by Feldman’s music. A survey of such challenges as they relate to his output in general is followed by an account of two particular issues associated with his late work: scale and repetition. Two case studies address these issues in turn, advancing relevant conceptual and methodological approaches. In the first study, on Coptic Light for orchestra (1985), I suggest that analysts might reconsider part–whole relationships in music analysis, and use the idea of ‘populations’ (with their attendant features of range of variation and distribution) to develop a non-reductive (and non-constructive) approach to scale. In the second study, on Piano, Violin, Viola, Cello (1987), I encourage analysts to rethink the role of repetition in music analysis, such that repetition is no longer (only) a goal, but becomes a point of departure. Throughout the essay I take the view that analysis is an investigation of experience; that a particular difficulty of analysing Feldman’s music is the self-knowledge it requires; and that the concerted inquiry that is music analysis can well be used to expand – not only condense – the realm of musical experience.
Darmstadt as Other: British and American Responses to Musical Modernism
Authors: HEILE BJÖRN
Published: April 2005

There is currently a backlash against modernism in English-language music studies. While this vogue of ‘modernism bashing’ is ostensibly based on progressive ideologies, it is dependent on a one-sided perception of musical modernism which it shares with earlier conservative disparagements. Of central importance in this respect is the ‘othering’ of musical modernism as an essentially continental European phenomenon in the ‘Anglosphere’, where it is consistently suspected of being a ‘foreign import’ – by conservative commentators in the first part of the twentieth century, just as by their ‘new-musicological’ successors at the turn of the twenty-first.

The example of the Anglo-American reception of the so-called Darmstadt school, usually regarded as quintessentially modernist, demonstrates how certain partial understandings and downright prejudices are handed down. For instance, the critical commonplace of Darmstadt’s presumed obsession with such values as technical innovation, structural coherence, and a scientistic rationalization of composition says more about those who coined it – mostly American critics who were uncomfortable with the aesthetic as well as the political radicalism of Darmstadt – than about the music itself. It is often precisely this depoliticized, sanitized construction of modernism that present-day critics have attacked, apparently unaware that this has always been a misrepresentation. By thus tracing some common misapprehensions in the Anglo-American reception of musical modernism, I want to argue for a fuller recognition of modernism’s essentially dialectical nature.
Exzessive Bestätigungssuche in sexuellen Abenteuern
Authors: Schwennen Christian , Bierhoff Hans-Werner
Published: April 2005

Zusammenfassung: Enge Beziehungen depressiver Personen unterscheiden sich hinsichtlich vieler Partnerschaftsvariablen von Beziehungen Nicht-Depressiver. Die vorliegende Studie prüft, welche Variablen gefundene Unterschiede in der Einstellung zur Partnerschaft erklären können. 139 Personen beantworteten das Einstellungs-Inventar für Liebesstile (MEIL), Skalen zur exzessiven Bestätigungssuche (BSS; BSS-SA) und die Allgemeine Depressions Skala (ADS). Außerdem machten sie Angaben zum Selbstwert, zur Beziehungszufriedenheit, zur Anzahl der bisherigen Partner und Ein-Nacht-Beziehungen. Die Kernhypothesen postulieren, dass Unterschiede hinsichtlich der Einstellung zur Partnerschaft bestehen, so dass depressiv Verstimmte stärker spielerisch orientiert sind als Nicht-Depressive. Zusätzlich sollte sich ihr Beziehungsverhalten durch mehr Ein-Nacht-Beziehungen kennzeichnen. Diese Unterschiede sollten durch Bestätigungssuche in sexuellen Abenteuern vermittelt werden. Die Ergebnisse bestätigen die Zusammenhänge mit Ausnahme der Ein-Nacht-Beziehungen. In der Beziehung zwischen depressiver Verstimmtheit und spielerischer Einstellung zur Partnerschaft (Ludus) nehmen Bestätigungssuche in sexuellen Abenteuern und exzessive Bestätigungssuche nur für Frauen jeweils eine Mediatorfunktion ein.
Strategische Verarbeitung beim Lernen mit Text und Hypertext
Authors: Richter Tobias , Naumann Johannes , Brunner Marion , Christmann Ursula
Published: April 2005

Zusammenfassung: Beim Lernen mit Hypertext müssen Lernende ihren Lernweg selbstständig zusammenstellen und auf verschiedene Knoten verteilte Lerninhalte zu einer kohärenten Gegenstandsrepräsentation integrieren. Diese Anforderungen sollten durch den Einsatz kognitiver und metakognitiver Lernstrategien besser bewältigt werden können. In diesem Beitrag werden Ergebnisse aus einer experimentell-korrelativen Untersuchung zur Rolle von Lernstrategien beim Lernen mit linearem Text und Hypertext berichtet. Psychologiestudierenden (N = 30) wurden studiumsnahe Lernaufgaben gestellt, die anhand eines Hypertexts oder eines inhaltsgleichen Lineartexts zu bearbeiten waren. Lernerfolgsmaße wurden über eine Inhaltsanalyse von Lernskripten ermittelt. Der Strategieneinsatz während der Textrezeption wurde über Protokolle lauten Denkens erfasst. Zusätzlich wurde das Navigationsverhalten in Logfiles aufgezeichnet. Der Einsatz kognitiver Lernstrategien erwies sich unabhängig von der Textstrukturvariante als lernförderlich. Zudem ließ sich der positive Effekt kognitiver Lernstrategien beim Lernen mit Hypertext partiell auf ein gründlicheres und systematischeres Navigationsverhalten zurückführen. Demnach ist eine aktiv-strategische Verarbeitung für Hyper- und Lineartextrezeption gleichermaßen funktional, wird aber bei der Hypertextrezeption in einer spezifischen Weise umgesetzt.
Förderung der Kohärenzbildung beim Lernen mit multiplen Repräsentationen
Authors: Brünken Roland , Seufert Tina , Zander Steffi
Published: April 2005

Zusammenfassung: Multimediale Lernumgebungen, die multiple Repräsentationen (z. B. Texte, Bilder, Tabellen etc.) enthalten, überlasten Lernende oftmals durch den hohen Aufwand der mentalen Kohärenzbildung. In drei experimentellen Drei-Gruppen-Studien wurde untersucht, ob der Wissenserwerb beim Lernen mit multiplen Repräsentationen durch instruktionale Kohärenzbildungshilfen gefördert werden kann. Dazu wurden je Experiment 57 bis 60 Lernenden jeweils Text-Bild-Kombinationen zum Herz-Kreislaufsystem dargeboten (Gruppe 1: visuell; Gruppe 2: audiovisuell; Gruppe 3: visuell mit Kohärenzbildungshilfe). Studie 1 untersuchte die lokale Fokussierung auf den Text, Studie 2 auf das Bild, während in der dritten Studie die globale Kohärenzbildung durch eine Fokussierung der Text-Bild-Bezüge unterstützt wurde. In allen 3 Studien wurde beim Vergleich visueller und audiovisueller Informationspräsentation ein modality effect gefunden. In Bezug auf die Kohärenzbildungshilfen konnte die textbezogene Hilfe textbezogene Leistung fördern und die Bildfokussierung förderte entsprechend die bildbezogene Leistung, aber nur die integrationsanleitende Hilfe unterstützte beide Leistungsbereiche. Die Ergebnisse zeigen, dass gezielte Kohärenzbildungshilfen den Wissenserwerb verbessern können.
Kein Mensch kann alles? Effekte dimensionaler Vergleiche auf das Fähigkeitsselbstkonzept
Authors: Dickhäuser Oliver , Seidler Alexandra , Kölzer Marika
Published: April 2005

Zusammenfassung: Referenzrahmenmodelle nehmen an, dass neben sozialen Vergleichen auch dimensionale Vergleiche Einfluss auf die Entstehung von Fähigkeitsselbstkonzepten nehmen. Haben Personen die Möglichkeit, die eigene Leistung in einem Bereich A mit schlechteren Leistungen in einem anderen Bereich B zu kontrastieren (dimensionaler Abwärtsvergleich), so soll dies zu einem Ansteigen des Fähigkeitsselbstkonzepts in Bezug auf A führen, ein dimensionaler Aufwärtsvergleich dagegen zu einem Absinken. In zwei Experimenten, in denen mit fingierter Leistungsrückmeldung gearbeitet wurde, zeigten sich tatsächlich Effekte dimensionaler Vergleichsinformation auf Fähigkeitsselbstkonzepte. Erstmals konnten im Experiment 2 sowohl positive Effekte dimensionaler Abwärtsvergleiche als auch negative Effekte dimensionaler Aufwärtsvergleiche nachgewiesen werden.
Neuropsychologische Defizite bei Ecstasykonsumenten
Authors: Wartberg Lutz , Petersen Kay Uwe , Andresen Burghard , Thomasius Rainer
Published: April 2005

Zusammenfassung: Einleitung: Neuere Untersuchungen diskutieren vermehrt den Einfluss von Cannabis zur Erklärung neuropsychologischer Beeinträchtigungen bei Ecstasykonsumenten. Methodik: Eine nach Alter, Bildung und kumulierter Cannabis-Dosis gleich verteilte Stichprobe von 24 Konsumenten von Ecstasy und Cannabis mit geringem Beikonsum von Kokain und LSD und 24 reinen Cannabiskonsumenten wurde neuropsychologisch untersucht. Ergebnisse: Die Ecstasykonsumenten zeigen in mehreren untersuchten Bereichen (Daueraufmerksamkeit, Kurz- und Langzeitgedächtnis) deutliche Beeinträchtigungen im Vergleich zu Probanden mit reinem Cannabiskonsum. Schlussfolgerungen: Dabei könnte es sich um Auswirkungen einer neurotoxischen Schädigung durch Ecstasy oder durch kombinierte Effekte von Ecstasy und Cannabis handeln. Die Ergebnisse der vorliegenden Untersuchung sprechen gegen eine zentrale Rolle von Cannabis zur Erklärung von kognitiven Defiziten bei Ecstasykonsumenten.
Constraining uplift and denudation of west African continental margin by inversion of stacking velocity data
Authors: Walford H. L. , White N. J.
Published: April 2005

An inverse model has been developed to determine the magnitude of denudation at seabed and subsurface unconformities by using root‐mean‐square (RMS) stacking velocity data derived from processing a set of seismic reflection profiles. This approach provides superior spatial coverage in comparison to other methods, such as vitrinite reflectance, apatite fission track, and sonic velocity modeling, which are restricted to borehole locations. The model assumes exponential porosity decay with depth and a standard velocity‐porosity relationship in order to compute a synthetic RMS velocity profile. Denudation values at two levels in the stratigraphy are then adjusted until the fit between the model and the data is optimized. Successful modeling is dependent upon independent estimates of the initial porosity of sediment since significant trade‐off occurs between initial porosity and denudation. Application to the west African shelf shows that 0.5–1 km of denudation occurred along the entire margin, probably during late Neogene times. The amount of denudation decreases oceanward and was probably triggered by regional tilting associated with initiation and/or regeneration of continent‐wide mantle convective upwelling, which is thought to have affected much of subequatorial Africa. A subsurface Oligocene unconformity represents as much as 2.5 km of denudation and was probably produced by initiation of an oceanic current.
Seasonal and diurnal variations in topsoil and subsoil respiration under snowpack in a temperate deciduous forest
Authors: Hirano Takashi
Published: April 2005

We measured soil CO2 concentration at half‐hour intervals with infrared gas analyzers buried in soil at four depths throughout the snow cover season extending from early December to early April in a deciduous temperate forest. We evaluated soil CO2 efflux or total soil respiration, topsoil (the A‐horizon) respiration, and subsoil (the C‐horizon) respiration using a modified flux gradient method. Thereby, we investigated seasonal and diurnal variations in these soil respirations under snowpack. Soil CO2 concentration and soil respiration changed dynamically under the condition of constant soil temperature. Topsoil respiration decreased rapidly in late autumn and relatively constant until mid‐winter, whereas it increased in late winter when snowmelt progressed. On the other hand, subsoil respiration decreased gradually until mid‐winter and increased slightly in late winter. Both topsoil and subsoil respirations showed similar diurnal variations with a peak in early or mid‐afternoon, respectively, independently of soil temperature. These seasonal and diurnal variations in soil respiration were inferred to result from the supply of labile carbon compounds, which were respiratory substrates for microorganisms, into soil from litter with meltwater. The seasonal sum of topsoil, subsoil, and total respirations for the snow cover period of 4 months were 21.4, 48.0, and 69.4 gC m−2, respectively; these accounted for 3.0, 27.3, and 7.7% of the annual sum, respectively. The ratio of topsoil respiration to total soil respiration was 0.31 on average during the snow period, which was considerably lower than that in the summer season.
Coupling of the random properties of the source and the ground motion for the 1999 Chi Chi earthquake
Authors: Lavallée Daniel , Archuleta Ralph J.
Published: April 2005

We show that both the slip distribution and the peak ground acceleration (PGA) for the 1999 Chi Chi earthquake can be described by Lévy laws. Furthermore, we found that the tails of the probability density functions (PDF) characterizing the slip and the ∣PGA∣ are governed by a parameter, the Lévy index, with almost the same values as predicted by the Central Limit theorem. The PDF tail controls the frequency at which extreme large events can occur. These events are the large stress drops–asperities–distributed over the fault surface and the large ∣PGA∣ observed in the ground motion. Our results suggest that the frequency of these events is coupled; the PDF of the ∣PGA∣ is a direct consequence of the PDF of the asperities. The physical rationale responsible for the coupling is the principle of superposition of wave signals characterized by random properties that are governed by the Central Limit theorem.
Deep flow variability in the vicinity of the Yucatan Straits from a high‐resolution numerical simulation
Authors: Chérubin Laurent M. , Sturges W. , Chassignet Eric P.
Published: April 2005

The deep flow variability in the vicinity of the Yucatan Channel between the Caribbean Sea and the Gulf of Mexico is examined within a high‐resolution numerical simulation of the North Atlantic Ocean. We focus on the 6 year integral cycle of Loop Current (LC) ring formation, and we study the flow regimes both in the Yucatan Channel and farther north in the LC. The circulation in the vicinity of the Yucatan Channel presents a high variability in the flow regimes and in the shedding period, in good agreement with earlier observations. The outflow (toward the Caribbean Sea) in the Yucatan Channel is shown to be controlled in part by a regular shift of the LC maximum velocity position, in phase with the transport variations. The outflow follows the inflow variations independently of the northward extension of the LC. Our analysis of the growth of the loop is also shown to be in good agreement with the ballooning process proposed by Pichevin and Nof (1997) and Nof and Pichevin (2001) to explain the LC ring formation. Moreover, at the end of each cycle of ring formation a sudden deepening of the LC deepest layer occurs together with an intensification of the transport and of the currents in the deep layers beneath the LC. This process is shown to be connected with the growth of cyclones in the deep layers. They result from the bottom‐intensified instability of the LC ring and contribute to its separation from the LC.
ISM observation of Phobos reinvestigated: Identification of a mixture of olivine and low‐calcium pyroxene
Authors: Gendrin Aline , Langevin Yves , Erard Stéphane
Published: April 2005

We reinvestigate the infrared spectral image cube of the Martian satellite Phobos obtained by the Infrared Spectrometer for Mars (ISM) instrument on board PHOBOS 2 using a band detection method based on the wavelet transform. Two absorption bands are identified at 1.04 μm and 1.9 μm. The position and profile of these bands are compatible with a mixture of low‐calcium pyroxene and olivine in specific regions on the surface of the satellite. This identification is confirmed by the strong spatial correlation of these two bands, which also corresponds to areas with a lower albedo. Finally, we discuss clues pointing toward possible local hydration of Phobos.
Nearshore wave‐induced cyclical flexing of sea cliffs
Authors: Adams Peter N. , Storlazzi Curt D. , Anderson Robert S.
Published: April 2005

Evolution of a tectonically active coast is driven by geomorphically destructive energy supplied by ocean waves. Wave energy is episodic and concentrated; sea cliffs are battered by the geomorphic wrecking ball every 4–25 s. We measure the response of sea cliffs to wave assault by sensing the ground motion using near‐coastal seismometers. Sea cliffs respond to waves in two distinct styles. High‐frequency motion (20 Hz) reflects the natural frequency of the sea cliff as it rings in response to direct wave impact. Low‐frequency motion in the 0.1–0.05 Hz (10–20 s) band consistently agrees with the dominant nearshore wave period. Integrating microseismic velocities suggests 50 μm and 10 μm displacements in horizontal and vertical directions, respectively. Displacement ellipsoids exhibit simultaneous downward and seaward sea cliff motion with each wave. Video footage corroborates the downward sea cliff flex in response to the imposed water load on the wave cut platform. Gradients in displacement amplitudes documented using multiple seismometers suggest longitudinal and shear strain of the flexing sea cliff on the order of 0.5–4 μ strains during each wave loading cycle. As this sea cliff flexure occurs approximately 3 million times annually, it has the potential to fatigue the rock through cyclical loading. Local sea cliff retreat rates of 10 cm/yr imply that a given parcel of rock is flexed through roughly 109 cycles of increasing amplitude before exposure to direct wave attack at the cliff face.
Climatic controls on diffuse groundwater recharge in semiarid environments of the southwestern United States
Authors: Small Eric E.
Published: April 2005

Although there is no diffuse groundwater recharge at many semiarid sites, evidence for diffuse recharge exists at some locations where mean annual precipitation is much less than mean annual potential evapotranspiration , particularly where soils are coarse and rainfall variable is substantial. We investigate the climatic controls on diffuse recharge using a one‐dimensional, variably saturated flow model. The model is driven by a stochastic parameterization of climate that includes storm size distribution and seasonality of precipitation (P) and potential evapotranspiration (PET), constrained by data from 536 weather stations in the southwestern United States. Storm size distribution and seasonality determine the frequency and duration of intervals when P exceeds PET, which controls the flux of water past the root zone. For coarse soils, climates with large, infrequent storms yield recharge when / exceeds 0.4, compared with 0.7 for a typical climate. Recharge through fine soils is insensitive to storm size and occurs at / > 0.8. Seasonality has a stronger influence on recharge than storm size distribution, and the effects are similar for coarse and fine soils. Recharge is relatively insensitive to rainfall seasonality. In contrast, the typical PET annual cycle lowers / of the recharge threshold by 0.3. The relative timing of P and PET maxima is critical: Recharge occurs at / values that are lower by 0.2 when the rainy season occurs during winter instead of summer. Over the range of climate and soils examined, / values at the recharge threshold varied from 0.2 to 0.7. Therefore and alone are insufficient to predict where recharge will occur.
Flux parameterization in the representative elementary watershed approach: Application to a natural basin
Authors: Reggiani P. , Rientjes T. H. M.
Published: April 2005

An integrated hydrological modeling approach based on the discretization of a watershed into spatial units called representative elementary watersheds (REWs) has been introduced in earlier publications. Global balance laws were formulated at the spatial scale of a REW by integrating the point‐scale conservation equations over particular control volumes. The choice of the control volumes is subject to the specific flow behavior to be described and is dependent on the hydrological characteristics of the spatial regions. These include the unsaturated subsurface flow, groundwater flow, and overland and channel flow. The REW‐scale balance laws constitute generally valid governing equations for environmental flows encountered in hydrological systems and are applicable, in contrast to point‐scale equations, independently from the chosen spatial and temporal scale of representation. This paper presents a first application of the REW approach to a complex hydrological system and shows how a theory that has so far only been used for synthetic cases is applicable to real‐world situations. In this context the most challenging research effort remains the formulation of appropriate closure schemes for mass and momentum (and energy) fluxes at the REW scale. It is recognized that the schemes proposed for the closure of the fluxes in this paper are subject to limitations but are sufficient to expose the philosophy and the essential working principles. The advantages of the particular spatial discretization and the current limitations of the closure schemes are highlighted. In this context it is pointed out which way future research should go to consolidate the REW approach as a more general and scale‐independent modeling philosophy for hydrological systems.
Generating and scaling fractional Brownian motion on finite domains
Authors: Cintoli Stefano , Neuman Shlomo P. , Di Federico Vittorio
Published: April 2005

Power variograms of statistically isotropic or anisotropic fractal fields (common in earth science) are weighted integrals of variograms representing statistically homogeneous fields (modes) having mutually uncorrelated increments. Large‐ and small‐scale cutoffs were previously assumed proportional to length scales of the sampling window and data support. We verify this assumption numerically for two‐dimensional isotropic fractional Brownian motion (fBm). It was previously concluded semi‐empirically that, for Hurst coefficient H = 0.25, the constant of proportionality is μ = 1/3. We confirm this but find μ to vary with mode type and H. We find that due to lack of ergodicity, sample fBm variograms generated on finite windows exhibit directional dependence and differ sharply between realizations. Many realizations are required to obtain an average sample variogram resembling the theoretical power model, especially for persistent fields. We propose generating fBm on finite windows using truncated power variograms and provide guidance for doing so effectively.
Induction and specification of the vertebrate ectodermal placodes: precursors of the cranial sensory organs
Authors: Brugmann Samantha A. , Moody Sally A.
Published: April 2005

The sensory organs of the vertebrate head derive from two embryological structures, the neural crest and the ectodermal placodes. Although quite a lot is known about the secreted and transcription factors that regulate neural crest development, until recently little was known about the molecular pathways that regulate placode development. Herein we review recent findings on the induction and specification of the pre‐placodal ectoderm, and the transcription factors that are involved in regulating placode fate and initial differentiation.
In memory of André Picard: 1950–2004
Authors: Kishimoto Takeo
Published: April 2005

André Picard, a cell and developmental biologist of starfish oocytes, died on 21 November 2004 at the age of 54 after a three‐year battle with prostate cancer. He was a Research Director of the CNRS at the Laboratoire Arago in Banyuls, France, and was awarded the Prix Foulon from the French Academy of Sciences in 2003.