bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct determination of endogenous melatonin in human saliva by column‐switching semi‐microcolumn liquid chromatography/mass spectrometry with on‐line analyte enrichment
Authors: Motoyama Akira , Kanda Taketoshi , Namba Ryujiro
Published: May 2004

An analytical method that enables direct and sensitive determination of endogenous melatonin (MLT) in human saliva was developed by means of column‐switching semi‐microcolumn liquid chromatography (i.d.: 1–2 mm)/mass spectrometry (LC/MS). The system allows direct injection analysis of a 400‐μL aliquot of saliva with minimal sample pretreatment (internal standard (IS) addition and vortex mixing) and a relatively short run‐time (10 min). The system consists of three columns to attain large volume injection and on‐line analyte enrichment. A pre‐column packed with a silica‐based mixed‐functional C8 (4.0 mm i.d. × 20 mm) was used for on‐line sample cleanup. MLT and an IS, the d7 isomer of MLT (d7‐MLT), were heart‐cut by valve switching and enriched at the top of the intermediate trapping column packed with a silica‐based C18 (4.0 mm i.d. × 10 mm). Subsequently, the analytes were backflushed into a semi‐micro C18 silica column (2.0 mm i.d. × 150 mm) for the final separation. MLT and IS were ascertained by positive electrospray ionization and selected ion monitoring (SIM). MLT was monitored based on its fragment ion at m/z 174.1 by in‐source collision‐induced dissociation (CID). The validation of this method revealed a detection limit of 2.5 pg mL−1 at a signal‐to‐noise (S/N) ratio of 5. The linearity of the method was established in the ranges 5–250 and 100–2500 pg mL−1 with a coefficient of determination of greater than 0.998. Accuracies, evaluated at five levels in the range 5–1000 pg mL−1, were between 81 and 108% with a relative standard deviation (RSD) ranging from 1.3–20%. The method was successfully applied for the endogenous saliva MLT monitoring of two healthy subjects. Copyright © 2004 John Wiley & Sons, Ltd.
Tetrahydrogestrinone: discovery, synthesis, and detection in urine
Authors: Catlin Don H. , Sekera Michael H. , Ahrens Brian D. , Starcevic Borislav , Chang Yu‐Chen , Hatton Caroline K.
Published: May 2004

Tetrahydrogestrinone (18a‐homo‐pregna‐4,9,11‐trien‐17β‐ol‐3‐one or THG) was identified in the residue of a spent syringe that had allegedly contained an anabolic steroid undetectable by sport doping control urine tests. THG was synthesized by hydrogenation of gestrinone and characterized by mass spectrometry and NMR spectroscopy. We developed and evaluated sensitive and specific methods for rapid screening of urine samples by liquid chromatography/tandem mass spectrometry (LC/MS/MS) of underivatized THG (using transitions m/z 313 to 241 and 313 to 159) and gas chromatography/high‐resolution mass spectrometry (GC/HRMS) analysis of the combination trimethylsilyl ether‐oxime derivative of THG (using fragments m/z 240.14, 254.15, 267.16, and 294.19). A baboon administration study showed that THG is excreted in urine. Copyright © 2004 John Wiley & Sons, Ltd.
ABCG2 – a transporter for all seasons
Authors: Sarkadi Balázs , Özvegy-Laczka Csilla , Német Katalin , Váradi András
Published: May 2004

The human ABCG2 (ABCP/MXR/BCRP) protein is a recently recognized ABC half‐transporter, which forms homodimers in the plasma membrane and actively extrudes a wide variety of chemically unrelated compounds from the cells. This protein protects our cells and tissues against various xenobiotics, with a crucial role in the intestine, liver, placenta, and the blood–brain barrier. Moreover, ABCG2 seems to have a key function in stem cell protection/regulation, and also in hypoxic defense mechanisms. Widely occurring single nucleotide polymorphisms in ABCG2 may affect absorption and distribution, altering the effectiveness and toxicity of drugs in large populations. At the clinics, overexpression of ABCG2 in tumor cells confers cancer multidrug resistance to a variety of newly developed anticancer agents. On the other hand, specific substrate mutants of ABCG2 are advocated for use as selectable markers in stem‐cell based gene therapy.
The TRAF6 RING finger domain mediates physical interaction with Ubc13
Authors: Wooff Jill , Pastushok Landon , Hanna Michelle , Fu Yu , Xiao Wei
Published: May 2004

Tumor necrosis factor receptor associated factor 6 (TRAF6) is an important signaling molecule involved in a diverse array of physiological processes. It has been proposed that TRAF6, a RING finger‐containing protein, acts as a ubiquitin ligase (E3) and a target for Lys‐63 linked polyubiquitination mediated by Ubc13–Uev, a ubiquitin conjugating (E2) complex. However, the physical interaction between TRAF6 and this E2 complex has not been reported. We used the yeast two‐hybrid assay to demonstrate that TRAF6 indeed interacts with the E2 complex through its direct binding to Ubc13. Either a single Cys‐to‐Ser substitution within the TRAF6 RING finger domain or an amino acid substitution on the Ubc13 surface, that is predicted to interact with RING finger proteins, is able to abolish the interaction. In addition, we found that TRAF6 can interact with itself and this self‐interaction domain is mapped to the N‐terminus containing the RING finger motif. Based on this study and our previous Ubc13–Uev structural analysis, the interface of Ubc13‐TRAF6 RING finger can be predicted.
Functionally and structurally relevant residues of enzymes: are they segregated or overlapping?
Authors: Magyar Csaba , Tüdős Éva , Simon István
Published: May 2004

There is a delicate balance between stability and flexibility needed for enzyme function. To avoid undesirable alteration of the functional properties during the evolutionary optimization of the structural stability under certain circumstances, and vice versa, to avoid unwanted changes of stability during the optimization of the functional properties of proteins, common sense would suggest that parts of the protein structure responsible for stability and parts responsible for function developed and evolved separately. This study shows that nature did not follow this anthropomorphic logic: the set of residues involved in function and those involved in structural stabilization of enzymes are rather overlapping than segregated.
Suppression of the caspase cleavage of β‐amyloid precursor protein by its cytoplasmic phosphorylation
Authors: Taru Hidenori , Yoshikawa Kazuaki , Suzuki Toshiharu
Published: May 2004

β‐Amyloid precursor protein (APP) is a type I transmembrane protein. Its cleavages by β‐ and γ‐secretases yield β‐amyloid, which is the main constituent of senile plaques in Alzheimer's disease (AD). In apoptotic cells and AD brains, APP is alternatively cleaved by caspases in the cytoplasmic region after the Asp664 residue (with respect to the numbering conversion for the APP695 isoform). Caspase‐cleaved fragments of APP are cytotoxic and have been implicated in AD pathogenesis; however, the mechanisms regulating the cleavage have not been studied. APP is constitutively phosphorylated at Thr668 in brain. In the present study, we demonstrate that APP phosphorylated at Thr668 is less vulnerable to cytoplasmic cleavage by caspase‐3 and caspase‐8. This suggests that APP phosphorylation suppresses the generation of caspase‐cleaved fragments of APP in the brain and that perturbation of this phosphorylation may be involved in APP‐mediated neurotoxicity.
Replicative senescence enhances apoptosis induced by pemphigus autoimmune antibodies in human keratinocytes
Authors: Wang Xin , Brégégère François , Soroka Yoram , Frusic-Zlotkin Marina , Milner Yoram
Published: May 2004

We have recently shown that skin lesions of the autoimmune disease pemphigus vulgaris are associated with Fas‐mediated apoptosis. Here, we describe the induction of the Fas‐dependent apoptosis pathway in cultured keratinocytes by pemphigus vulgaris autoantibodies (PV‐IgG), as seen from a variety of cellular, morphological and biochemical parameters. All apoptotic characters appear stronger and faster in aged cultures than in young, showing increased susceptibility of senescent keratinocytes to PV‐IgG‐mediated apoptotic death and culture lesions. Together with immunosenescence, this phenomenon may explain the late onset of pemphigus disease.
Taxonomic versus trophic structure of mesozooplankton: a seasonal study of species succession and stable carbon and nitrogen isotopes in a coastal upwelling ecosystem
Authors: Bode Antonio , Alvarez-Ossorio Maria Teresa
Published: May 2004

Seasonal variations in mesozooplankton (>200 μm) stable carbon and nitrogen isotope abundances were compared with the seasonal species succession pattern off A Coruña (Galicia, NW Spain). Mesozooplankton biomass, numerical abundance, species composition, and natural abundance of stable isotopes, along with water column temperature, salinity, chlorophyll a and dissolved nitrate concentrations, were studied in monthly samples during the years 2000 and 2001 at a coastal station (80-m depth). Biomass and abundance of mesozooplankton followed the annual cycle with maxima in spring and summer (year 2000) and occasionally also in autumn (year 2001). The succession pattern shown by the taxonomic assemblages was recognized in both years of study, despite differences in the timing of upwelling and the large input of continental water during most of 2000. Variations in neither carbon nor nitrogen isotopes were correlated with either abundance or biomass at annual time scales, but heavy isotopes significantly accumulated during periods of zooplankton increase (spring and early summer). The consumption of nitrate during the spring can explain in part the progressive accumulation of heavy nitrogen isotopes during this period. In addition, the abundance of carnivorous zooplankton (mainly carnivorous copepods, siphonophores, and chaetognaths) was linearly related to the increase in heavy isotopes during the spring and, in the case of nitrogen, also during the whole study period. The computed linear relationships between isotope abundances and plankton species composition provided a way to further analyse the pelagic foodweb through the estimation of isotope reference values for primary consumers.
The influence of oxidation on proteolysis in raw milk
Authors: Wiking Lars , Nielsen Jacob H
Published: May 2004

The link between oxidation and increased proteolysis in raw milk was studied. To accelerate oxidation, H2O2 (1 mM) was added to raw milk, resulting in enhanced proteolysis by up to 11·2% after 24 h incubation at 5 °C. Addition of Cu2+ (10 μM) to milk or exposure of milk to light (60 min) likewise increased proteolysis. To explain the mechanism responsible for increased proteolysis as a result of oxidation, the effect of lipid oxidation products on plasmin-induced proteolysis was tested. Addition of malondialdehyde to skim milk increased the formation of γ-caseins, a proteolysis product from plasmin hydrolysis of β-casein. The same observation was made in a model system containing 4·5 g β-casein/l sodium tetraborate buffer at pH 8 and plasmin. Addition of a plasmin inhibitor blocked the formation of γ-casein. The results indicate that aldehydes accumulated from lipid oxidation can modify β-casein and thereby increase susceptibility of the proteins to proteolysis. Furthermore, the data suggest that proteolysis in raw milk may be connected to oxidative processes.
Hormone-dependent milk protein gene expression in bovine mammary explants from biopsies at different stages of pregnancy
Authors: Sheehy Paul A , Della-Vedova James J , Nicholas Kevin R , Wynn Peter C
Published: May 2004

A method for the collection of mammary biopsies developed previously was refined and used to study the endocrine regulation of bovine milk protein gene expression. Our surgical biopsy method used real-time ultrasound imaging and epidural analgesia to enable recovery of a sufficient quantity of mammary tissue from late-pregnant dairy cows for explant culture in vitro. The time of biopsy was critical for prolactin-dependent induction of milk protein gene expression in mammary explants, as only mammary tissue from cows nearing 30 d prepartum was hormone-responsive. This suggests that during the later stages of pregnancy a change in the responsiveness of milk protein gene expression to endocrine stimuli occurred in preparation for lactation. This may relate to the diminution of a putative population of undifferentiated cells that were still responsive to prolactin. Alternatively, the metabolic activity of the tissue had increased to the level whereby the response of the tissue was no longer assessable using this model in vitro.
Effect of recombinant cytokines on leucocytes and physiological changes in bovine mammary glands during early involution
Authors: Wedlock D Neil , McCarthy Allison R , Doolin Elizabeth E , Lacy-Hulbert S Jane , Woolford Murray W , Buddle Bryce M
Published: May 2004

We examined the effects of administering recombinant bovine cytokines to non-lactating dairy cows and measured mammary gland leucocytes and the involution process. After the final milking, groups of cows were given an intramammary infusion of cytokine in two quarters. These cytokines were recombinant bovine interleukin-2 (rboIL-2) (2×105 units, n=6), recombinant bovine granulocyte-macrophage colony stimulating factor (rboGM-CSF) (500 μg, n=4) and recombinant bovine interleukin-1β (rboIL-1β) (10 μg, n=10). Each animal also received an infusion of phosphate-buffered saline (PBS) in the other two quarters as controls. The rboIL-2 and rboGM-CSF were produced in a yeast expression system, while rboIL-1β was produced in Escherichia coli. Leucocyte numbers, bactericidal activity of leucocytes, and concentrations of citrate and lactoferrin in quarter secretion samples were monitored after infusion of cytokine or PBS. Infusion of rboIL-2 had minimal effect on leucocyte numbers and concentrations of citrate and lactoferrin. Both rboGM-CSF and rboIL-1β induced a rapid increase in the number of neutrophils and macrophages compared with control PBS quarters. Concentrations of lactoferrin in secretions were increased by rboGM-CSF and rboIL-1β compared with control PBS quarters. In addition, infusion of glands with rboIL-1β lowered the citrate[ratio ]lactoferrin molar ratio compared with PBS control quarters. The results indicate that intramammary infusion of either rboGM-CSF or rboIL-1β at cessation of milking immediately increased the number of phagocytic cells in the gland. These cytokines, in particular rboIL-1β, also increased the rate of mammary gland involution during the early dry period.
High-level coproduction of the bacteriocins nisin A and lactococcin A by Lactococcus lactis
Authors: Fernández Antonio , Horn Nikki , Gasson Michael J , Dodd Helen M , Rodríguez Juan M
Published: May 2004

In this study, a two-plasmid system for enhanced and consistent biosynthesis of the model lactococcal bacteriocin lactococcin A in non-producing Lactococcus lactis hosts was developed. The system comprised a plasmid carrying the genes lcnA and lciA under the control of the nisin-inducible nisA promoter, and a second plasmid harbouring the lcnC and lcnD genes. The introduction of both plasmids into two strains containing the nisRK genes required for nisin-controlled expression, Lc. lactis FI5876 (a nisin A-producer strain) and FI7847, resulted in production of extracellular lactococcin A at a higher level than that for the parental strain, Lc. lactis WM4. In addition, transformation of the nisin-producing host with both plasmids led to a high-level production of both lactococcal bacteriocins, which may provide a means to exploit their complementary properties in cheese ripening.
Thermal stability of β-lactoglobulins A and B: effect of SDS, urea, cysteine and N-ethylmaleimide
Authors: Boye Joyce I , Ma Ching Y , Ismail Ashraf
Published: May 2004

Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) were used to monitor changes in the secondary structure and thermal stability of β-lactoglobulin A and B in the presence of sodium dodecyl sulphate (SDS), N-ethylmaleimide (NEM), urea and cysteine. An increase in the thermal stabilities of both proteins was noted in the presence of 10 mM-SDS. In the presence of 50 mM-SDS, there was extensive denaturation of both variants. In general, the β-strand/β-sheet regions in the secondary structure of both variants were very susceptible to denaturation by SDS and cysteine, suggesting that these regions may be held by hydrophobic and disulphide bonds. At ambient temperature and physiological pH, a notable difference was observed in the 1636 and 1627 cm−1 regions of the FTIR spectra of the two β-lg variants. The results suggest possible differences in the nature of the β-sheet/β-strand distribution/content of the two proteins. Urea and NEM at a concentration of 50 mM, had little effect on the secondary structure and denaturation of both variants. New findings are presented which further indicate that although the β-lg B variant showed greater thermal stability than the A variant in all the cases studied, its denaturation temperature and secondary structure were affected to a greater extent by the protein perturbants than β-lg A.
Scandinavian pancake sentences as semantic agreement
Authors: Enger Hans-Olav
Published: May 2004

This paper deals with Scandinavian sentences where the predicative adjective apparently disagrees with its subject, such as pannekaker er godt ‘pancakes-pl. is good-neut.sg.’, vodka er sunt ‘vodka-masc. is healthy-neut.sg.’. In this paper, the use of neuter in such sentences is seen as a case of semantic agreement. Thereby, pancake sentences comply with Corbett's (1979) agreement hierarchy. The controllers in pancake sentences are low on the individuation scale. This is the reason why they are neuters. The controllers in pancake sentences are mirror-images of the controllers in more well-known examples of semantic agreement. Not only morphosyntax but also semantics, pragmatics and discourse play a role in agreement.
The Precedent of Appeals Chambers Decisions in the International Criminal Tribunals
Authors: TRACOL XAVIER
Published: May 2004

The principle of judicial precedent set out by the Appeals Chamber of the International Criminal Tribunal for the former Yugoslavia raises the five following issues. (i) Is the Appeals Chamber bound by its previous decisions? (ii) Are the trial chambers bound by Appeals Chamber decisions on both legal and factual issues? (iii) Are the trial chambers bound by the decisions of other trial chambers? (iv) Is the Appeals Chamber of the ICTY bound by the decisions of the Appeals Chamber of the International Criminal Tribunal for Rwanda (ICTR) and vice versa? (v) Are the trial chambers of the ICTR bound by the decisions of the ICTY Appeals Chamber and vice versa? The author of this article aims to show that the Appeals Chambers, most trial chambers and individual judges of the International Criminal Tribunals comply with the principle of judicial precedent. However, the principle of judicial precedent is arguably weak, because it was established by case law only. The author also intends to demonstrate that the trial chambers and an individual trial judge of the ICTY have recently departed from the practice of judicial precedent in sensitive legal areas, that is (i) the test to be applied to a motion for a judgement of acquittal; (ii) the issue of evidence; (iii) the standard to be applied to a motion for cross-access to confidential documents in other cases; and (iv) the issue of provisional release.
Öcalan v. Turkey: Some Comments
Authors: KÜNZLI ANNEMARIEKE
Published: May 2004

In the Öcalan case the European Court of Human Rights found itself faced with several issues that asked for a new interpretation of the European Convention on Human Rights. It had to decide on the extraterritorial scope of the Convention, on the question whether Abdullah Öcalan was arrested lawfully or illegally abducted, and on the death penalty. This article analyzes the decisions taken by the Court and puts them in a perspective of international law beyond the European Convention.
Human pregnancy: the role of chemokine networks at the fetal–maternal interface
Authors: Red-Horse Kristy , Drake Penelope M. , Fisher Susan J.
Published: May 2004

Chemokines are multifunctional molecules initially described as having a role in leukocyte trafficking and later found to participate in developmental processes such as differentiation and directed migration. Similar events occur in pregnancy during development of the fetal–maternal interface, where there is extensive leukocyte trafficking and tissue morphogenesis, and this is accompanied by abundant chemokine expression. The relationship between chemokines, leukocytes and placental development is beginning to be delineated. During pregnancy a specialised population of maternal leukocytes infiltrates the implantation site. These leukocytes are thought to sustain the delicate balance between protecting the developing embryo/fetus and tolerating its hemiallogeneic tissues. A network of chemokine expression by both fetal and maternal components in the pregnant uterus functions in establishing this leukocyte population. Intriguingly, experiments investigating immune cell recruitment revealed the additional possibility that chemokines influence aspects of placental development. Specifically, cytotrophoblasts, the effector cells of the placenta, express chemokine receptors that can bind ligands found at key locations, implicating chemokines as regulators of cytotrophoblast differentiation and migration. Thus, as in other systems, at the fetal–maternal interface chemokines might regulate multiple functions.
Consumer‐food systems: why type I functional responses are exclusive to filter feeders
Authors: Jeschke Jonathan M. , Kopp Michael , Tollrian Ralph
Published: May 2004

The functional response of a consumer is the relationship between its consumption rate and the abundance of its food. A functional response is said to be of type I if consumption rate increases linearly with food abundance up to a threshold level at which it remains constant. According to conventional wisdom, such type I responses are more frequent among filter feeders than among other consumers. However, the validity of this claim has never been tested. We review 814 functional responses from 235 studies, thereby showing that type I responses are not only exceptionally frequent among filter feeders but that they have only been reported from these consumers.

These findings can be understood by considering the conditions that a consumer must fulfil in order to show a type I response. First, the handling condition: the consumer must have a negligibly small handling time (i.e. the time needed for capturing and eating a food item), or it must be able to search for and to capture food while handling other food. Second, the satiation condition: unless its gut is completely filled and gut passage time is minimal, the consumer must search for food at a maximal rate with maximal effort. It thus has to spend much time on foraging (i.e. searching for food and handling it).

Our functional response review suggests that only filter feeders sometimes meet both of these conditions. This suggestion is reasonable because filter feeders typically fulfil the handling condition and can meet the satiation condition without losing time, for they are, by contrast to non‐filter feeders, able simultaneously to perform foraging and non‐foraging activities, such as migration or reproduction.
A Return Potential Measure of Setting Norms for Aggression
Authors: Henry David B. , Cartland Jennifer , Ruchross Holly , Monahan Kathleen
Published: May 2004

This study tested a classroom‐level measure of norms based on J. Jackson's (1966) Return Potential Model. “Return potential” refers to the probability of approval of aggression in a given setting or group, and the return potential model allows quantification of different aspects of a setting's norms. Return potential measures were computed for unprovoked and provoked aggression. A pilot sample of 236 students in 11 classrooms and a main sample of 3,304 students in 158 classrooms completed this measure and a self‐report measure of aggression. Results from hierarchical linear models showed that all measures of classroom return potential for aggression were significantly clustered by classrooms. Four return potential measures had main effects on aggression, and four measures showed variation in effects by grade or urban residence. Differences in clustering and effects by grade suggested age differences in the importance of different normative characteristics.
Religious Activity and Risk Behavior Among African American Adolescents: Concurrent and Developmental Effects
Authors: Steinman Kenneth J. , Zimmerman Marc A.
Published: May 2004

This study examines how religious activity is associated with risk behaviors, concurrently and developmentally among urban African American adolescents. Seven hundred and five African American youths were interviewed annually during high school. Retention rates for the study exceeded 90%. Frequency of religious activity, sexual intercourse, and alcohol, cigarette, and marijuana use were assessed at each wave. Growth curve analyses found negative concurrent associations between religious activity and each of the four risk behaviors. The developmental effects of religious activity varied by gender. Higher levels of religious activity in 9th grade predicted smaller increases in marijuana use among males and cigarette use among females. In addition, larger decreases in religious activity during high school were associated with greater increases in alcohol use among males and sexual intercourse among females. During high school, religious activity limits the development of certain types of risk behavior among African American youth, even after controlling for reciprocal effects.
Readiness, Functioning, and Perceived Effectiveness in Community Prevention Coalitions: A Study of Communities That Care
Authors: Feinberg Mark E. , Greenberg Mark T. , Osgood D. Wayne
Published: May 2004

This paper examined whether community readiness, prevention knowledge, coalition functioning, and barriers are linked to perceived effectiveness of community prevention coalitions. Interviews were conducted with 203 key leaders in Communities That Care (CTC) prevention boards in 21 Pennsylvania communities. Community‐level means for the reliable self‐report measures were utilized separately and in combination with research staff ratings, state technical assistant staff ratings, and other data. The results indicated that the strong link between readiness and perceived effectiveness was mediated by internal coalition functioning. The extent of CTC linkage with outside community entities was not linked to perceived effectiveness. The study concludes that community readiness is an important condition for success of a prevention coalition, and exerts effects mainly through the quality of the coalition's internal functioning. Member turnover and infighting appear to be important factors related to internal functioning. Linkage with outside entities may be more important for coalition models where the coalition is more dependent on local institutions for resources.
When One Plus One Equals Three: The Role of Relationships and Context in Community Research
Authors: Brodsky Anne E. , Senuta Kathleen Rogers , Weiss Catharine L. A. , Marx Christine M. , Loomis Colleen , Arteaga S. Sonia , Moore Heidi , Benhorin Rona , Castagnera-Fletcher Alisha
Published: May 2004

This paper explores the role of relationships within and between the community of the researchers and the community of the research participants, as they relate to qualitative, community psychology research. Although relationships are salient to all research, their role is particularly prominent in qualitative research, in which a closer rapport is established between researcher and research participant than in quantitative research, and the impact of both sides of this interaction on the research process is acknowledged. Instead of merely looking at the community and relationships of the participants, the usual focus of research, this paper also explores the often‐overlooked community and relationships of the researchers and then goes on to look at the impact on the research process of the interaction of these two separate communities. This inside story, while seldom explicitly explored or articulated, has implications for community research in general and particularly for applied research.
The Need for Action When Conducting Intervention Research: The Multiple Roles of Community Psychologists
Authors: Balcazar Fabricio E. , Garate-Serafini Teresa J. , Keys Christopher B.
Published: May 2004

In choosing to implement empowering interventions with marginalized populations, community psychologists often have to merge research and action. We present three case stories that exemplify empowerment efforts in the context of a multi‐year school intervention designed to develop the advocacy skills of ethnic minority students' with disabilities and promote attainment of transition‐related goals. In the process of implementing the intervention, our research team had to instigate change, advocate, and/or mediate in multiple conflictual interactions between the various stakeholders in the schools. We faced both positive and negative consequences for our actions. We discuss the responsibilities of community psychologists in the process of empowering others and the implications for the practice of community research.
Doing Community Research Without a Community: Creating Safe Space for Rape Survivors
Authors: Campbell Rebecca , Sefl Tracy , Wasco Sharon M. , Ahrens Courtney E.
Published: May 2004

This paper describes how the values of a feminist research team influenced methodological decisions in a study of rape survivors. Building upon concepts from community psychology and urban sociology, the authors created a community‐based research design that respected the emotional needs of rape survivors without sacrificing methodological rigor. We developed relationships with community members in diverse settings, such as nail and hair salons, child care centers, churches, and bookstores, to advertise the study and recruit participants. Consistent with feminist approaches to interviewing, our goal was to create a safe setting for survivors to tell their stories. Although the purpose of this study was research rather than intervention, most survivors reported that participating in these interviews was healing. Our experiences in this project suggest that allowing values to influence the process of research may have beneficial outcomes for both researchers and participants.
Unheard Alaska: Culturally Anchored Participatory Action Research on Sobriety with Alaska Natives
Authors: Mohatt Gerald V. , Hazel Kelly L. , Allen James , Stachelrodt Mary , Hensel Chase , Fath Robert
Published: May 2004

Alcohol research in Alaska Native communities has a contentious history. This project has attempted to address a critical need for research to guide alcohol abuse prevention and treatment with Alaska Natives using culturally anchored participatory action research. The process of grounding the research methodology in the culture and community is described, along with its contribution to community psychology's understanding of the importance of cultural factors. Tensions between indigenous values and ways of knowing, and Western research methodologies are delineated, along with how these tensions were resolved. Important issues that arose in doing culturally anchored participatory action research are described. These included the development of a community of inquiry, key methodological decisions, the empowerment of participants as coresearchers, and flexibility in research implementation.
Überprüfung der Stadienspezifität der Processes of Change bei Besuchern eines internetbasierten Expertensystems zur Bewegungsförderung
Authors: Martin-Diener Eva , Thüring Nicole
Published: May 2004

Zusammenfassung. Gemäß Transtheoretischem Modell unterstützen zehn Änderungsstrategien den Prozess einer Verhaltensänderung. Basierend auf Erkenntnissen aus der Rauchentwöhnung postuliert das Modell, dass in der ersten Phase des Veränderungsprozesses (Precontemplation, Contemplation, Preparation) primär kognitiv-affektive Strategien, in der zweiten Phase (Action, Maintenance) behaviorale Strategien eingesetzt werden. Dies wurde für den Bereich der körperlichen Aktivität mit Daten von 644 Besuchern eines internetbasierten Expertensystems zur Bewegungsförderung überprüft. Innerhalb der ersten drei Stadien der Verhaltensänderung wurden mehr kognitiv-affektive Strategien, innerhalb der letzten zwei Stadien mehr behaviorale Strategien gebraucht. Der Einsatz der kognitiv-affektiven Strategien nahm von der ersten zur zweiten Phase ab, während der Gebrauch der behavioralen Strategien zunahm. Der Einsatz der kognitiv-affektiven Strategien stieg vom ersten zum zweiten Stadium signifikant an. Der Gebrauch der behavioralen Strategien nahm vom ersten bis zum vierten Stadium kontinuierlich zu. Die aus dem Modell abgeleiteten Erwartungen wurden für die dichotome Phaseneinteilung vollständig, für den Verlauf über die fünf Stadien teilweise bestätigt.
Verhaltensspezifische Determinanten der Veränderungsmotivation bei multiplem Risikoverhalten
Authors: Thyrian Jochen René , Rumpf Hans-Jürgen , Meyer Christian , Hapke Ulfert , John Ulrich
Published: May 2004

Zusammenfassung. Es fehlen Untersuchungen zur gleichzeitigen Betrachtung mehrerer Risikoverhaltensweisen im Rahmen des Transtheoretischen Modells der Verhaltensänderung (TTM). In Deutschland gelten Tabakrauchen und Alkoholtrinken als wichtigste verhaltensbezogene Ursache für Morbidität und Mortalität. Für beide Verhaltensweisen findet sich eine Koinzidenz. Der Zusammenhang zwischen der Veränderungsbereitschaft beim Tabakrauchen und der Veränderungsbereitschaft des Alkoholtrinkens aus der Perspektive des TTM ist jedoch unklar. Diese Studie betrachtet eine Gruppe von n = 137 Personen, aus einer repräsentativen Bevölkerungsstichprobe von 18-64-Jährigen, die Tabak rauchen und einen riskanten Alkoholkonsum zeigen. Es wird der Zusammenhang von Alkoholtrinken und Tabakrauchen bezüglich der TTM-Konstrukte Stufe der Veränderungsbereitschaft, Entscheidungsbalance, Selbstwirksamkeitserwartung und Prozesse der Verhaltensänderung untersucht. Es besteht nur ein geringer Zusammenhang zwischen den Stufen der Veränderungsbereitschaft beider Verhaltensbereiche. Bei der Hälfte der Prozesse zeigen sich ebenfalls geringe Zusammenhänge über die Verhaltensweisen hinweg, ebenso bei der Selbstwirksamkeitserwartung und den wahrgenommenen Vorteilen der Verhaltensweisen. Die Ergebnisse differenzieren verhaltensspezifische und -unspezifische Konstrukte; Schlussfolgerungen für multibehaviorale Interventionen und die Weiterentwicklung des TTM werden gezogen, und die Ergebnisse werden vor dem Hintergrund der methodischen Einschränkungen dieser Studie kritisch diskutiert.
Bedingungen für die Bereitschaft zur Organspende
Authors: Keller Stefan , Bölting Kristin , Kaluza Gert , Schulz Karl-Heinz , Ewers Heike , Robbins Mark L. , Basler Heinz-Dieter
Published: May 2004

Zusammenfassung. Trotz einer überwiegend positiven Einstellung zur Organspende besitzen in der Bundesrepublik Deutschland lediglich etwa 12% der Bevölkerung einen Organspendeausweis. Somit besteht eine starke Diskrepanz zwischen der Anzahl benötigter und zur Verfügung stehender Spenderorgane. Anknüpfend an erste Arbeiten im amerikanischen Raum geht die vorliegende Arbeit den Fragen nach, welche Merkmale die Bereitschaft, Organspender zu werden, bestimmen und in welchem Maße die Konstrukte des Transtheoretischen Modells (TTM) zur Beschreibung und Erklärung des Entscheidungsprozesses zur Organspende beitragen. In einer anfallenden Stichprobe von n = 325 Personen (55% Frauen, Altersdurchschnitt 38 Jahre) wurden in einer Querschnittsbefragung soziodemographische Variablen, Einstellungen zur Organspende sowie die Operationalisierungen der Konstrukte des TTM bezogen auf das Zielverhalten “Ausfüllen eines Organspendeausweises und Mitteilen der Entscheidung in der Familie“ erhoben. Die Ergebnisse zeigen, dass 61% der Befragten noch keine Entscheidung getroffen haben und dies auch nicht in absehbarer Zeit beabsichtigen (Stufe der Absichtslosigkeit). Die Bereitschaft zur Organspende (operationalisiert durch die Stufen der Verhaltensänderung) ist wenig abhängig von soziodemographischen Merkmalen mit Ausnahme eines leichten Zusammenhanges mit religiösen Überzeugungen. Erwartungsgemäß zeigt sich, dass vor allem die Gruppe der Personen in der Stufe der Absichtslosigkeit durch vergleichsweise niedrige wahrgenommene Vorteile, eine niedrige Selbstwirksamkeit und hohe Werte für die wahrgenommenen Nachteile einer Entscheidung zur Organspende gekennzeichnet ist. Die Ergebnisse deuten an, dass der Entscheidungsprozess bzgl. der Organspende durch die Konstrukte des TTM abgebildet werden kann. Diese Ergebnisse werden vor dem Hintergrund ihrer möglichen Bedeutung für die Entwicklungen von Interventionen zur Förderung der Organspendebereitschaft diskutiert. Weitere Studien sollten insbesondere größere und bevölkerungsrepräsentativere Stichproben einbeziehen. Zudem sollten die aus dem amerikanischen übertragenen Messinstrumente noch einmal hinsichtlich der Vollständigkeit kulturspezifisch relevanter Items überprüft werden.
Anticyclonic‐cyclonic eddies and their impact on near‐surface chlorophyll stocks and oxygen supersaturation over the Campeche Canyon, Gulf of Mexico
Authors: Salas‐de‐León David Alberto , Monreal‐Gómez María Adela , Signoret Martha , Aldeco Javier
Published: May 2004

Physical and biological data were gathered over the Campeche Canyon area, Gulf of Mexico, in summer 1999. These include hydrographical and meteorological parameters, and oxygen content, as well as, at some oceanographic stations, suspended particulate matter (SPM), chlorophyll‐a, and in vivo natural fluorescence profiles. Dry air from the east set up a latent heat flux that ranged from 50 to 300 Wm−2. The wind mixed layer (ML) was isothermal and averaged 40 m thick, but with a noticeable increase of oxygen supersaturation toward the northwest. Temperature and dynamic height structure reveal an anticyclone‐cyclone eddy pair. At the southeastern part of the study area a noticeable thermal gradient was observed toward the shelf break of the Campeche Bank, which corresponded to a tilting up (doming) of low oxygen saturation midwater to near the base of the ML. This doming of isotherms along the margin of the Campeche escarpment is likely an upper‐ocean response to the sharp gradient in water depth between the canyon and outer continental shelf. It is suggested that the doming of midwater on to the Campeche escarpment and at the head of the Canyon, as denoted by locally low values of oxygen saturation, plays an important role in the biological patterns. Throughout the field area, the values of total SPM were higher than reported previously for subtropical open ocean environments. The impact of autotrophic‐heterotrophic biogeochemical processes on chlorophyll was reflected in the local deepening of the deep of chlorophyll maximum (DCM) and the depth of the euphotic zone within the anticyclonic eddy.
Particles in the great Pinatubo volcanic cloud of June 1991: The role of ice
Authors: Guo Song , Rose William I. , Bluth Gregg J. S. , Watson I. Matthew
Published: May 2004

Pinatubo's 15 June 1991 eruption was Earth's largest of the last 25 years, and it formed a substantial volcanic cloud. We present results of analysis of satellite‐based infrared remote sensing using Advanced Very High Resolution Radiometer (AVHRR) and TIROS Operational Vertical Sounder/High Resolution Infrared Radiation Sounder/2 (TOVS/HIRS/2) sensors, during the first few days of atmospheric residence of the Pinatubo volcanic cloud, as it drifted from the Philippines toward Africa. An SO2‐rich upper (25 km) portion drifted westward slightly faster than an ash‐rich lower (22 km) part, though uncertainty exists due to difficulty in precisely locating the ash cloud. The Pinatubo clouds contained particles of ice, ash, and sulfate which could be sensed with infrared satellite data. Multispectral IR data from HIRS/2 were most useful for sensing the Pinatubo clouds because substantial amounts of both ice and ash were present. Ice and ash particles had peak masses of about 80 and 50 Mt, respectively, within the first day of atmospheric residence and declined very rapidly to values that were <10 Mt within 3 days. Ice and ash declined at a similar rate, and it seems likely that ice and ash formed mixed aggregates which enhanced fallout. Sulfate particles were detected in the volcanic cloud by IR satellites very soon after eruption, and their masses increased systematically at a rate consistent with their formation from SO2, which was slowly decreasing in mass during the same period. The initially detected sulfate mass was 4 Mt (equivalent to 3 Mt SO2) and after 5 days was 12–16 Mt (equivalent to 9–12 Mt SO2).
Evidence of a large seasonal coastal upwelling system along the southern shelf of Australia
Authors: Kämpf Jochen , Doubell Mark , Griffin David , Matthews Roger L. , Ward Tim M.
Published: May 2004

We report observational existence of a large seasonal coastal upwelling system that establishes in austral summer (December–April) along Australian southern shelves. Wind‐driven upwelling events occur simultaneously in three upwelling centres spanning a distance of ∼800 km. During each summer period there are ∼2–3 major upwelling events, each lasting ∼1 week. The simultaneous, rapid response of SST to wind forcing in the upwelling centres, which display vastly different shelf widths, points to the existence of a larger‐scale process that carries cold water onto the shelf prior to the upwelling season. Exploration of a major upwelling event in March 1998 shows the evolution of peak surface chlorophyll‐a concentrations of >4 μg/L lagging the onset of upwelling by ∼1 week. The associated (exponential) growth rate can be estimated at 0.4 d−1. Another week later we found a distinct sub‐surface chlorophyll‐a maximum at a depth of 50 m centred along the upwelling front. Reasons for the formation of this maximum are not fully understood.
Nonlinear interaction among internal wave beams generated by tidal flow over supercritical topography
Authors: Lamb K. G.
Published: May 2004

Internal wave beams are generated by tidal flow over topography. For supercritical topography the beams are narrower and higher harmonic beams more pronounced than for subcritical topography. Numerical simulations show that nonlinear interactions between two topographically generated beams generate internal wave beams with the sum and difference frequencies, significantly modifying the super‐tidal frequency portion of the internal wave field in the vicinity of supercritical topographic features.
Modeling the properties of guided poloidal Alfvén waves with finite asymmetric ionospheric conductivities in a dipole field
Authors: Ozeke L. G. , Mann I. R.
Published: May 2004

Analytical and numerical solutions to the guided poloidal Alfvén wave equation in a dipole field are developed, including the effects of realistic and asymmetric finite ionospheric conductivities. We show that when the ionospheric Pedersen conductivity in one hemisphere is less than a critical value, then quarter‐wavelength harmonic modes become possible. We present solutions using realistic plasma density variations along the field line and illustrate how the electric and magnetic fields of a field‐aligned half‐wavelength harmonic mode change as the ionospheric conductivities are made increasingly asymmetric and the wave develops into a quarter‐wavelength mode. Further, we show how over a small critical range of ionospheric Pedersen conductivities, the wave damping rates and frequencies change rapidly as this transition from half‐ to quarter‐wavelength mode occurs. We also show that the phase difference between the electric and magnetic field components is strongly dependent upon the distance along the magnetic field line, upon the asymmetry in the ionospheric Pedersen conductivities, and significantly upon which hemisphere has its footprint in the ionosphere whose conductivity is close to critical. This has important implications for inferring the field‐aligned harmonic mode of standing ULF pulsations when using single satellite data.
Dispersionless modulations in low‐energy solar electron bursts and discontinuous changes in the solar wind electron strahl
Authors: Gosling J. T. , de Koning C. A. , Skoug R. M. , Steinberg J. T. , McComas D. J.
Published: May 2004

The solar wind experiment on the Advanced Composition Explorer (ACE) has detected at least 328 impulsive solar electron bursts that exhibited energy and angle dispersion at onset at energies below 1.4 keV in the interval from 1 January 1998 through 30 September 2003. Discontinuous, dispersionless modulations in burst intensity and pitch angle occurred in a subset of these events. These dispersionless modulations were similar to discontinuous modulations in the solar wind electron strahl intensity often observed at these same energies at other times. During the bursts themselves, dispersionless modulations in burst intensity commonly, but not always, were associated with discontinuous changes in the underlying strahl intensity. At times the burst intensity modulations were correlated with the strahl modulations and at times they were anticorrelated with the strahl modulations. We find that the variety of types of dispersionless burst/strahl modulations observed within low‐energy solar electron bursts can largely be explained in terms of a simple model that assumes spatially limited burst source regions, a strahl intensity that varies with coronal magnetic connection point, and magnetic field line foot point motions in the solar atmosphere during the 2–4 days it takes solar wind plasma and the embedded heliospheric magnetic field to travel from the Sun to 1 AU.
Assessing precipitation products in the Indian Ocean using an ocean model
Authors: Yu Z. , McCreary J. P.
Published: May 2004

Precipitation is one of the main forcings for sea surface salinity (SSS). The accuracy of precipitation products over open oceans, however, remains a problem due to the lack of in situ measurements. In this study, we use an ocean model to test the performance of precipitation products in the Indian Ocean, where large salinity contrasts exist. The model consists of four active layers overlying a deep, inert ocean, the top‐most layer being a mixed layer governed by Kraus‐Turner physics. Solutions are forced by monthly‐mean precipitation climatologies, and their surface salinity fields (S1) are compared with observed SSS. In the Indian Ocean, both river runoff and the Indonesian throughflow significantly influence the long‐term mean SSS distribution, and hence adequate treatment of these boundary forcings is a prerequisite for the model to be useful as a tool for evaluating precipitation products. We also explored the sensitivity of solutions to various model parameters and forcing, making sure they are not the main source of the bias. The model produces the best annual‐mean S1 field when it is forced by the Climate Prediction Center Merged Analysis of Precipitation (CMAP) product, a merged precipitation product based on rain‐gauge data and several satellite estimates. An amplitude adjustment of the Global Precipitation Climatology Project (GPCP) product is suggested by the model S1, supporting the notion that merged products give reliable spatial patterns but not necessarily correct magnitudes. Problems with some other precipitation products are also discussed, in terms of their potential distortion of mixed‐layer thickness.