bluuebunny/crossref_metadata_2025 huggingface dataset:
Signaling the trustworthiness of small online retailers
Authors: Wang Sijun , Beatty Sharon E. , Foxx William
Published: February 2004

One of the major challenges facing all online retailers, especially small online retailers, is how to initiate consumer trust. This study examines the nature of this unique type of consumer trust by proposing the concept of “cue-based trust.” It also examines the signaling role of various cues in building initial trust and the behavioral consequences involved. A 25–1 factorial experiment was conducted with sample size of 402 to explore the signaling effects of five cues of interest in this study: seals of approval, return policy, awards from neutral sources, security disclosures, and privacy disclosures. The online study supported the signaling roles of most of these cues. Findings can be summarized as follows: (a) security disclosures and awards from neutral sources were found to enhance cue-based trust which, in turn, positively influenced two behavioral responses—bookmarking intentions and willingness to provide personal information, and (b) seals of approval and privacy disclosures were found to directly encourage consumers’ willingness to provide personal information while awards from neutral sources were found to directly encourage bookmarking intentions. Implications for online retailers and future theoretical studies are discussed.
Electronic word-of-mouth via consumer-opinion platforms: What motivates consumers to articulate themselves on the Internet?
Authors: Hennig-Thurau Thorsten , Gwinner Kevin P. , Walsh Gianfranco , Gremler Dwayne D.
Published: February 2004

Through Web-based consumer opinion platforms (e.g., epinions.com), the Internet enables customers to share their opinions on, and experiences with, goods and services with a multitude of other consumers; that is, to engage in electronic word-of-mouth (eWOM) communication. Drawing on findings from research on virtual communities and traditional word-of-mouth literature, a typology for motives of consumer online articulation is developed. Using an online sample of some 2,000 consumers, information on the structure and relevance of the motives of consumers’ online articulations is generated. The resulting analysis suggests that consumers’ desire for social interaction, desire for economic incentives, their concern for other consumers, and the potential to enhance their own self-worth are the primary factors leading to eWOM behavior. Further, eWOM providers can be grouped based on what motivates their behavior, suggesting that firms may need to develop different strategies for encouraging eWOM behavior among their users.
CD4+CD25+ regulatory T cells suppress tumor immunity but are sensitive to cyclophosphamide which allows immunotherapy of established tumors to be curative
Authors: Ghiringhelli François , Larmonier Nicolas , Schmitt Elise , Parcellier Arnaud , Cathelin Dominique , Garrido Carmen , Chauffert Bruno , Solary Eric , Bonnotte Bernard , Martin François
Published: February 2004

We investigated the mechanisms of immune tolerance raised by tumors by comparing immunogenic and tolerogenic tumor cell clones isolated from a rat colon carcinoma. When injected into syngeneichosts, the immunogenic REGb cells yield tumors that are rejected, while the tolerogenic PROb cells yield progressive tumors and inhibit the regression of REGb tumors. We show here that PROb tumor volume is correlated with an expansion of CD4+CD25+ regulatory T lymphocytes in lymphoid tissues. These cells delay in vivo the rejection of REGb tumors and inhibit in vitro T cell‐mediated immune responses against REGb cells through a mechanism that requires cell contact between effector and regulatory T cells and involves TGF‐β. While total T cells fromPROb tumor‐bearing rats yield no apparent anti‐tumor immune response, depletion of CD25+ T cells restores this reactivity. A single administration of cyclophosphamide depletes CD4+CD25+ T cells in PROb tumor‐bearing animals, delays the growth of PROb tumors, and cures rats bearing established PROb tumors when followed by an immunotherapy which has no curative effect when administered alone. These results demonstrate the role of CD4+CD25+ regulatory T cells in tumor‐induced immune tolerance and the interest of regulatory T cell depletion to sensitize established tumors to immunotherapy.
A CIITA‐independent pathway that promotes expression of endogenous rather than exogenous peptides in immune‐privileged sites
Authors: Arancibia‐Cárcamo Carolina V. , Osawa Hideya , Arnett Heather A. , Háskova Zdenka , George Andrew J. T. , Ono Santa J. , Ting Jenny P.‐Y. , Streilein J. Wayne
Published: February 2004

A CIITA‐independent pathway of MHC class II expression has been found in the eye and the brain, both immune‐privileged sites. Although corneal endothelial cells were unable to express MHC class II in response to IFN‐γ alone, these cells readily expressed MHC class II molecules via a CIITA‐independent pathway when triggered by simultaneous exposure to IFN‐γ and TNF‐α. CIITA‐independent expression of MHCclass II molecules enabled corneal endothelial cells to present cytosolic, but not endosomal, ovalbumin (OVA) to OVA‐primed T cells. To determine whether CIITA‐independentexpression of MHC class II is relevant in vivo, minor H‐only‐incompatible corneal allografts prepared from CIITA knockout (KO) mice, MHC class II KO mice or wild‐type donors were placed ineyes of normal mice. Cornea allografts from wild‐type and CIITA KO mice suffered similar rejection fates, whereas far fewer class II‐deficient corneas were rejected. In addition, MHC class II‐bearing macrophages were observed in cuprizone‐induced inflammatory and demyelinating brain lesions of CIITA KO mice. We conclude that class II expression via the CIITA‐independent pathway enhances the vulnerability to rejection of corneal grafts expressing minor antigens. The potential relevance of CIITA‐independent MHC class II expression at immune‐privileged sites is discussed in relation to tolerance to strong autoantigens.
Ethyl α‐(Triphenylphosphoranylidene)amino‐β‐ferrocenylacrylate as a Starting Material for [2+2] Cycloadditions, Including the Aza‐Wittig Reaction
Authors: Csámpai Antal , Túrós György , Kudar Veronika , Simon Kálmán , Oeynhausen Hendrik , Wamhoff Heinrich , Sohár Pál
Published: February 2004

Ethyl α‐(triphenylphosphoranylidene)amino‐β‐ferrocenylacrylate, synthesized from the corresponding azide, was treated with a few selected electrophilic agents potentially capable of undergoing the aza‐Wittig reaction. The transformations with aroyl chlorides and phenylisocyanate afforded a series of novel 4‐(ferrocenyl)methylidene‐2‐aryloxazolones. On treatment of the phosphorimino compound with DMAD two competitive reactions took place on the C=C and N=P bonds, giving rise to a novel amino(ferrocenyl)butadiene and a ferrocenyl‐substituted aza‐pentadienylphosphorylide, respectively. The parent azidoferrocenylacrylate underwent the expected 1,3‐dipolar cycloaddition with DMAD, resulting in a triester of a (ferrocenyl)vinyl‐substituted v‐triazoletricarboxylate suitable for a variety of further heterocyclic syntheses. The structures of the new compounds were determined by IR and NMR spectroscopy, mass spectrometry, and X‐ray analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Another Aspect of the Reaction Behavior of Cyclopentadienones: 1,5‐Sigmatropic Rearrangement of the 1,4‐Addition Products of Amines
Authors: Yamaguchi Koki , Kai Chika , Yoshitake Yasuyuki , Harano Kazunobu
Published: February 2004

Treatment of 2,5‐bis(methoxycarbonyl)‐3,4‐diphenylcyclopentadienone (1) with aniline (2a) gave the stereoisomeric 2‐anilino‐2,5‐bis(methoxycarbonyl)‐3,4‐diphenylcyclopentenones (cis‐ and trans‐4a). 1H NMR spectroscopic monitoring of the reaction indicates that both compounds are derived from the 1,5‐sigmatropic rearrangement of the 1,4‐addition products cis‐ and trans‐3a. The structure of 3a was established by the X‐ray analysis of the product after methylation (3a‐Enol‐Me) with diazomethane. The sequential pericyclic reaction behavior of 1 with amines is discussed on the basis of X‐ray crystal structures and the optimized structure of the transition state at the B3LYP/6−31G(d) level of theory. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Regulatory changes and information competition: The case of Taiwan index futures
Authors: Hsieh Wen‐liang Gideon
Published: February 2004

This article examines the cross‐border competition in price discovery between the Taiwan Futures
Exchange (TAIFEX) and the Singapore Exchange Derivatives Trading (SGX). We focused on the
impact of market reforms on the information leadership of similar contracts traded on the two exchanges. Utilizing
synchronized transaction data, it was found that reducing the futures transferring tax was the only policy change
that enhanced TAIFEX's information role. Evidence supported the trading‐cost hypothesis that a lower
transaction cost is associated with better price discovery. A brief linkage between trading volume and price
discovery was found when data were broken down into subperiods according to the relative volume of TAIFEX and SGX.
Evidence suggested that the SGX's information advantage reported in previous research had diminished as the
rival market progressed. It also indicated that exchanges seeking to improve information efficiency should adopt
policies that will reduce transaction costs or increase trading volume. © 2004 Wiley Periodicals, Inc. Jrl
Fut Mark 24:399–412, 2004
Electrochemistry and Spectroscopy of Sulfate Complexes of (Tetraphenylporphyrinato)manganese
Authors: Lawson Kevin , Gross Jeff , Crawford Philip W.
Published: February 2004

The electrochemical and spectroscopic properties of [Mn2(tpp)2(SO4)] (H2tpp=tetraphenylporphyrin=5,10,15,20‐tetraphenyl‐21H,23H‐porphine) were studied to characterize the stability of this compound as a function of solvent, redox state, and sulfate concentration. In non‐coordinating solvents such as 1,2‐dichloroethane, the dimer was stable, and two cyclic voltammetric waves were observed in the region for MnIII reduction. These waves correspond to reduction of the dimer to [MnII(tpp)] and [MnIII(tpp)(OSO3)]−, and reduction of [MnIII(tpp)(OSO3)]− to [MnII(tpp)(OSO3)]2−, respectively. In the coordinating solvent DMSO, [Mn2(tpp)2(SO4)] was unstable and dissociated to form [MnIII(tpp)(DMSO)2]+. A single voltammetric wave was observed for MnIII reduction in this solvent, corresponding to formation of [MnII(tpp)(DMSO)]. In non‐coordinating solvent systems, addition of sulfate (as the bis(triphenylphosphoranylidene)ammonium (PPN+) salt) resulted in dimer dissociation, yielding [MnIII(tpp)(OSO3)]−. Reduction of this monomer produced [MnII(tpp)(OSO3)]2−. In DMSO, addition of SO$\rm{_{4}^{2-}}$ led to displacement of solvent molecules forming [MnIII(tpp)(OSO3)]−. Reduction of this species in DMSO led to [MnII(tpp)(DMSO)].
A Combined Experimental and Theoretical Approach toward the Development of Optimized Luminescent Carbostyrils
Authors: Strohmeier Gernot A. , Fabian Walter M. F. , Uray Georg
Published: February 2004

The synthesis and photophysical data of new carbostyrils (quinoline‐2(1H)‐ones) with the longest hitherto observed absorption‐ and emission wavelengths are described. Introduction of 6‐amino, 7‐MeO, and 4‐(CF3) substituents enabled us to rise the absorption and fluorescence maxima up to 414 and 557 nm, respectively. Supported by semi‐empirical and ab initio calculations, the 6,7‐(1,4‐diazine)‐fused carbostyril 23b displayed absorption maxima at up to 440 nm, with quantum yields of up to 0.9 and large Stokes shifts (>100 nm), comparable to the best coumarin chromophores known. The new fluorophore is neither pH‐sensitive between pH 6 and 10 nor susceptible to O2 quenching. At pH 3, the emitted light appears greenish‐white, which arises from three different stages of protonation.
Spiromarienonols A and B: Two New 7(8→9)abeo‐Lanostane‐Type Triterpene Lactones from the Stem Bark of Abies mariesii
Authors: Tanaka Reiko , Wada Shun‐ichi , Aoki Hitoshi , Matsunaga Shunyo , Yamori Takao
Published: February 2004

Two new skeletal triterpene lactones, spiromarienonols A (1a) and B (2a), were isolated from the stem bark of Abies mariesii Masters (Pinaceae). Based on spectral data and biogenetic considerations, their unique three‐dimensional structures were determined to be (3R,7S,9R,23R)‐ (1a) and (3R,7S,9S,23R)‐3,7‐dihydroxy‐8‐oxo‐7(8→9)abeo‐lanost‐24‐eno‐26,23‐lactone (2a). Moreover, the potent activity of abiesenonic acid methyl ester (3) and abieslactone (4) against a disease‐oriented panel of 39 human cancer cell lines were investigated.
Communities coping with change: A conceptual model
Authors: Kelly Gail J. , Steed Lyndall G.
Published: February 2004

Changing economic, political, environmental, and social conditions continue to have a cumulative impact on Australian regional communities, and in many instances, rural communities are being forced to initiate their own strategies in order to remain economically and socially viable. However, while communities respond in differing ways to similar change events, as do individuals, research examining the change process has largely been undertaken at the individual level. This article reports on an investigation of the characteristics that moderate a community's ability to manage change and the types of collective coping strategies communities employ to deal with change events. A model of community change process was used as the framework to examine the links between community characteristics, appraisal of change events (forest restructuring and tourism), and the use of collective strategies in three communities in Western Australia. Findings suggest that a community's mobilization of strategies is dependent on the collective assessment of the change event, the nature of the event, and the characteristics of the community. The implications for intervention through policy and community development are discussed briefly. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 201–216, 2004.
Molecular characterization of lactic acid populations associated with wine spoilage
Authors: Beneduce L. , Spano G. , Vernile A. , Tarantino D. , Massa S.
Published: February 2004

We have investigated the prevalence of spoilage lactic acid bacteria (LAB) in table wines produced in the Apulia region. The occurrence of LAB was evaluated in wines produced with low sulphur dioxide doses and not supplemented with selected malolactic starters such as Oenococcus oeni. About 150 strains were isolated from wine must and a molecular characterization was performed using PCR‐based techniques. Most of the strains analysed belonged to Lactobacillus plantarum species. However, some of the strains were identified as Pediococcus damnosus and Leuconostoc sp. The amplified fragments of Pediococcus damnosus were cloned and sequenced. The coding sequence was highly homologous to that of the ropy plasmid confirming that the isolated strain was a ropy+ Pediococcus damnosus. In all the samples analysed, the final must pH value reached was relatively high (from 3.78 to 3.90). The high pH values had probably negatively influenced (counteracted) the activity of sulphur dioxide added, allowing proliferation of spoilage wine microorganisms.
Isolation and characterization of microorganisms capable of decolorizing various triphenylmethane dyes
Authors: Sharma Deepak Kumar , Saini Harvinder Singh , Singh Manjinder , Chimni Swapandeep Singh , Chadha Bhupinder Singh
Published: February 2004

Various soil and sludge samples collected from the vicinity of textile dyeing industries and waste disposal sites were used for enrichment of microbial population in the presence of triphenylmethane (TPM) dye Acid Violet‐17 (AV‐17). Twenty‐five (25) isolates were screened for their ability to decolorize AV‐17 dye added at a rate of 10 mgl−1 in mineral salts medium (MSM) agar plates. Five bacterial isolates belonging to Bacillus sp., Alcaligenes sp. and Aeromonas sp. were selected on the basis of their higher decolorization ability and were used to develop a bacterial consortium. The consortium was able to efficiently decolorize various TPM dyes viz. Acid Violet‐17 (86%), Acid Blue‐15 (85%), Crystal Violet (82%), Malachite Green (82%) and Brilliant Green (85%). The consortium will be further used for designing efficient and cost effective treatment system for effluents of textile processing industries (TPI).
Consequences of the failure of the axiom of choice in the theory of Lindelöf metric spaces
Authors: Keremedis Kyriakos
Published: February 2004

We study within the framework of Zermelo‐Fraenkel set theory ZF the role that the axiom of choice plays in the theory of Lindelöf metric spaces. We show that in ZF the weak choice principles: (i) Every Lindelöf metric space is separable and (ii) Every Lindelöf metric space is second countable (Forms 340 and 341, respectively, in [10]) are equivalent. We also prove that a Lindelöf metric space is hereditarily separable iff it is hereditarily Lindelöf iff it hold as well the axiom of choice restricted to countable sets and to topologies of Lindelöf metric spaces as the countable union theorem restricted to Lindelöf metric spaces. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A secondary semantics for Second Order Intuitionistic Propositional Logic
Authors: Ferrari Mauro , Fiorentini Camillo , Fiorino Guido
Published: February 2004

In this paper we propose a Kripke‐style semantics for second order intuitionistic propositional logic and we provide a semantical proof of the disjunction and the explicit definability property. Moreover, we provide a tableau calculus which is sound and complete with respect to such a semantics. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural effect of linear and star‐shaped poly(L‐lactic acid) on physical properties
Authors: Kim Eun Sub , Kim Byoung Chul , Kim Soo Hyun
Published: February 2004

The linear and star‐shaped poly(L‐lactic acid) (PLLA) with similar molecular weight were prepared and their physical properties such as thermal properties, rheological properties, and crystallization behavior in quiescent and dynamic states were compared. The differential scanning calorimetry showed that the linear PLLA gave higher glass transition, melting, and crystallization temperatures than the star‐shaped one. In dynamic crystallization, the linear PLLA gave longer induction time and longer overall crystallization time than the star‐shaped one, although the former gave higher rate of crystallization in quiescent crystallization. However, wide‐angle X‐ray diffractometer(WAXD) analysis revealed that the linear and star‐shaped PLLA developed the same crystal structure and application of shear had little effect on crystal structure. As predicted, the linear PLLA gave higher crystallinity than the star‐shaped PLLA. In the dilute solutions, the linear PLLA exhibited higher intrinsic viscosity than the star‐shaped one. In the concentrated solutions, the star‐shaped PLLA gave higher values of dynamic viscosity, storage, and loss moduli than the linear one. Further, the former exhibited more noticeable shear thinning behavior and greater dependence of rheological properties on temperature than the latter. For both PLLA melts, the modified Cole–Cole plot gave slope less than 2. Of two PLLA polymers the star‐shaped PLLA gave smaller slope than the linear one. In addition, the former showed greater change of the slope with temperature than the latter. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 939–946, 2004
Brillouin scattering studies of polymeric nanostructures *
Authors: Hartschuh R. , Ding Y. , Roh J. H. , Kisliuk A. , Sokolov A. P. , Soles C. L. , Jones R. L. , Hu T. J. , Wu W. L. , Mahorowala A. P.
Published: February 2004

For a range of applications, polymers are now being patterned into nanometer‐sized features. In these applications, the robust mechanical properties of the nanostructures are critical for performance and stability. Brillouin light scattering is presented as a nondestructive, noncontact tool used to quantify the elastic constants in such nanostructures. We demonstrate this through a series of thin films and parallel ridges and spacings (gratings) with ridge widths ranging from 180 to 80 nm. For the set of films and structures presented here, the room‐temperature elastic moduli did not change with decreasing film thickness or grating ridge width, and this implied that one‐dimensional and two‐dimensional confinement‐induced changes of the mechanical properties were not significant down to feature sizes of 80 nm. Additionally, Brillouin spectra of submicrometer gratings revealed new modes not present in the spectra of thin films. The origin of these new modes remains unclear. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1106–1113, 2004
Gepulstes Heißdraht‐Vakuummeter mit Pirani‐Sensor. Pulsed hot filament vacuum gauge with Pirani sensor
Authors: Jitschin W. , Ludwig S.
Published: February 2004

Das Heißdraht‐Vakuummeter nach Pirani wird üblicherweise im stationären Zustand betrieben, in welchem zugeführte elektrische Heizleistung und Wärmeverluste im Gleichgewicht sind. Die Wärmeverluste durch Wärmeleitung des Gases nehmen mit steigendem Druck zu, woraus das Messsignal zur Druckbestimmung erhalten wird. Allerdings beginnt oberhalb von etwa 100 mbar die Wärmeleitung zu sättigen, so dass in diesem Bereich mit dem Heißdraht‐Vakuummeter keine genauen Messungen mehr möglich sind. Vor einigen Jahren wurde der Vorschlag veröffentlicht, das Heißdraht‐Vakuummeter gepulst zu betreiben, um die Wärmekapazität des Gases, die proportional zum Druck ist, zur Druckbestimmung auszunutzen. Gegenstand der vorliegenden Arbeit ist eine aussagefähige Untersuchung des dynamischen Verhaltens des Pirani‐Sensors. Hierzu wurden sowohl der Aufheizvorgang als auch der Abkühlprozess des Drahtes für verschiedene Drücke gemessen. Wie die Messdaten und Abschätzungen zeigen, steckt zwar bei Atmosphärendruck eine respektable Energie im Gas, wesentlich mehr als im Draht, jedoch werden hiervon Aufheizung und Abkühlung verhältnismäßig wenig beeinflußt. Grund hierfür sind die hohen Wärmeverluste durch Wärmeleitung des Gases, die recht schwache thermische Ankopplung des Gases an den Draht sowie die geringe mittlere Erwärmung des Gases. Weiterhin wurde ein intermittierender Betrieb des Pirani‐Sensors erprobt, bei dem die Versorgungsspannung des Drahtes allmählich ansteigt. Vorteile dieser Betriebsart sind eine deutliche Verbesserung der Messeigenschaften oberhalb von 100 mbar und eine erhebliche Reduzierung der Leistungsaufnahme.
Exploring Risk in Early Adolescent African American Youth
Authors: Farmer Thomas W. , Price LeShawndra N. , O'Neal Keri K. , Leung Man-Chi , Goforth Jennifer B. , Cairns Beverley D. , Reese Le'Roy E.
Published: February 2004

Two studies were conducted to explore the degree to which single‐ and multiple‐risk profiles were evident in samples of African American early adolescents in low‐income inner‐city, rural, and suburban schools. Study 1 examined early adolescent risk status (i.e., single, multiple) in relation to later adjustment in a representative sample (70% European American, 30% African American). Youth who experienced a single risk in early adolescence had moderately increased levels of school dropout and criminal arrests, whereas youth with multiple risks (i.e., combination of 2 or more risks) had significantly increased levels of school dropout, criminal arrests, and teen parenthood. Study 2 examined the extent to which single‐ and multiple‐risk profiles were evident in cross‐sectional samples of African American youth from low‐income inner‐city and rural areas. About one fourth of both the inner‐city and rural samples of African American youth were composed of youth in the single‐risk category. A significantly greater proportion of boys in the inner‐city sample (20%) than boys in the rural sample (13%) experienced multiple risks. Girls across the rural and inner‐city samples did not differ in terms of risk. Overall, more than 60% of African American youth in these two low‐income samples did not evidence risk for later adjustment problems. Implications for research and intervention are discussed.
Die sogenannte Krise der psychologischen Diagnostik
Authors: Westmeyer Hans
Published: February 2004

Zusammenfassung. Die Diagnostica als traditionsreichste deutschsprachige Zeitschrift für Psychologische Diagnostik und Differentielle Psychologie feiert 2004 ihr 50-jähriges Bestehen. Aus diesem Anlass wird an die 70er Jahre des 20. Jahrhunderts erinnert, in denen sich die psychologische Diagnostik Anfeindungen von vielen Seiten gegenüber sah und die Rede von einer Krise der psychologischen Diagnostik in den deutschsprachigen Ländern mit Ausnahme der DDR die Runde machte. Auf einige Ursachen für die damalige Krisenstimmung wird eingegangen, u.a. auf den Aufstieg der Verhaltensdiagnostik, die Kritik am medizinischen Modell psychischer Störungen, die Ablehnung einer Selektionszwecken dienenden Diagnostik aus gesellschaftstheoretischer Perspektive und die Zweifel an den psychometrischen Grundlagen der traditionellen eigenschaftsorientierten Diagnostik. Die kritischen Auseinandersetzungen um die psychologische Diagnostik blieben nicht ohne Auswirkungen auf die Diagnostica, deren Entwicklung von Mitte der 70er Jahre bis Mitte der 90er Jahre in diesem Beitrag nachgezeichnet wird.
Konstruktion einer Ratingskala mit Smilies als symbolische Marken
Authors: Jäger Ruth
Published: February 2004

Zusammenfassung. In einem 2-stufigen Prozess wurde eine aus 5 Smilies (stilisierten Gesichtern) bestehende Ratingskala mit dem Ziel konstruiert, gleichabständige auf einer Dimension liegende Skalenmarken zu erhalten. Ausgangsmaterial waren 17 Smilies mit systematisch variierter Mundpartie. In Untersuchung 1 (graphisches Bewertungsrating, N1 = 108) wurde die Skala generiert und in Untersuchung 2 (vollständiger Ähnlichkeitspaarvergleich, N2 = 131) wurden die ausgewählten 5 Smilies über eine Nonmetrische Multidimensionale Skalierung auf Eindimensionalität und Äquidistanz getestet. Die Skala erscheint geeignet zur Erhebung emotional konnotierter Urteile wie Befindlichkeit, Zustimmung, Zufriedenheit.
Productivity control of fine particle transport to equatorial Pacific sediment
Authors: Thomas E. , Turekian K. K. , Wei K.‐Y.
Published: February 2004

Accumulation rates of 3He (from cosmic dust), 230Th (produced in the water column), barite (produced in the water column during decay of organic matter), and Fe and Ti (arriving with wind‐borne dust) all are positively correlated in an equatorial Pacific core (TT013‐PC72; 01.1°N, 139.4°W; water depth 4298 m). These accumulation rates are also positively correlated with the accumulation rates of noncarbonate material. They are not significantly correlated to the mass accumulation rate of carbonate, which makes up the bulk of the sediment. The fluctuations in accumulation rates of these various components from different sources thus must result from variations in some process within the oceans and not from variations in their original sources. Sediment focusing by oceanic bottom currents has been proposed as this process [Marcantonio et al., 1996]. We argue that the variations in the accumulation rates of all these components are dominantly linked to changes in productivity and particle scavenging (3He, 230Th, Fe, Ti) by fresh phytoplankton detritus (which delivers Ba upon its decay) in the equatorial Pacific upwelling region. We speculate that as equatorial Pacific productivity is a major component of global oceanic productivity, its variations over time might be reflected in variations in atmospheric levels of methanesulfonic acid (an atmospheric reaction product of dimethyl sulfide, which is produced by oceanic phytoplankton) and recorded in Antarctic ice cores.
Radar interferogram filtering for geophysical applications
Authors: Goldstein Richard M. , Werner Charles L.
Published: February 2004

The use of SAR interferometry is often impeded by decorrelation from thermal noise, temporal change, and baseline geometry. Power spectra of interferograms are typically the sum of a narrow‐band component combined with broad‐band noise. We describe a new adaptive filtering algorithm that dramatically lowers phase noise, improving both measurement accuracy and phase unwrapping, while demonstrating graceful degradation in regions of pure noise. The performance of the filter is demonstrated with SAR data from the ERS satellites over the Jakobshavns glacier of Greenland.
Effects of a mid‐latitude solar eclipse on the thermosphere and ionosphere ‐ A modelling study
Authors: Müller‐Wodarg I. C. F. , Aylward A. D. , Lockwood M.
Published: February 2004

A modelling study is presented which investigates in‐situ generated changes of the thermosphere and ionosphere during a solar eclipse. Neutral temperatures are expected to drop by up to 40°K at 240 km height in the totality footprint, with neutral winds of up to 26 m/s responding to the change of pressure. Both temperatures and winds are found to respond with a time lag of 30 min after the passing of the Moon's shadow. A gravity wave is generated in the neutral atmosphere and propagates into the opposite hemisphere at around 300 m/s. The combined effects of thermal cooling and downwelling lead to an overall increase in [O], while [N2] initially rises and then for several hours after the eclipse is below the “steady state” level. An enhancement of [NmF2] is found and explained by the atmosphere's contraction during, and the reduced [O]/[N2] ratio after the eclipse.
Aviation fuel tracer simulation: Model intercomparison and implications
Authors: Danilin M. Y. , Fahey D. W. , Schumann U. , Prather M. J. , Penner J. E. , Ko M. K. W. , Weisenstein D. K. , Jackman C. H. , Pitari G. , Köhler I. , Sausen R. , Weaver C. J. , Douglass A. R. , Connell P. S. , Kinnison D. E. , Dentener F. J. , Fleming E. L. , Berntsen T. K. , Isaksen I. S. A. , Haywood J. M. , Kärcher B.
Published: February 2004

An upper limit for aircraft‐produced perturbations to aerosols and gaseous exhaust products in the upper troposphere and lower stratosphere (UT/LS) is derived using the 1992 aviation fuel tracer simulation performed by eleven global atmospheric models. Key findings are that subsonic aircraft emissions: 1) have not be responsible for the observed water vapor trends at 40°N; 2) could be a significant source of soot mass near 12 km, but not at 20 km, 3) might cause a noticeable increase in the background sulfate aerosol surface area and number densities (but not mass density) near the northern mid‐latitude tropopause, and 4) could provide a global, annual mean top of the atmosphere radiative forcing up to +0.006 W/m² and −0.013 W/m² due to emitted soot and sulfur, respectively.
Crustal deformation in the Baikal Rift from GPS measurements
Authors: Calais Eric , Lesne Olivia , Déverchère Jacques , San'kov Vladimir , Lukhnev Andrei , Miroshnitchenko Andrei , Buddo Vladimir , Levi Kirill , Zalutzky Vjacheslav , Bashkuev Yuri
Published: February 2004

Three years and four campaigns of Global Positioning System (GPS) measurements (1994–1997) in the Baikal rift zone, largest active continental rift system in Eurasia, show crustal extension at a rate of 4.5±1.2 mm/yr in a WNW‐ESE direction. A comparison with moment release of large historical earthquakes suggests that elastic strain is currently accumulating in the Baikal rift zone along active faults that currently have the potential for a M=7.5 earthquake. The GPS‐derived extension rate in the Baikal rift zone is at least two times greater than the prediction of most deformation models of Asia. This result could reflect the dynamic contribution of the Pacific‐Eurasia subduction to intracontinental deformation in Asia, in addition to the effect of the India‐Eurasia collision.
Energetic auroral electron distributions derived from global X‐ray measurements and comparison with in‐situ particle measurements
Authors: Anderson P. C. , Chenette D. L. , McKenzie D. L. , Quinn J. M. , Grande M. , Carter M.
Published: February 2004

On May, 27, 1996, the Polar Ionospheric X‐ray Imaging Experiment (PIXIE) on board NASA's POLAR spacecraft was imaging the southern auroral oval during an auroral substorm. Near simultaneous particle measurements by the DMSP F12 and F13 and POLAR satellites allow us to compare measured energetic electron distributions with distributions derived from the x‐ray measurements; agreement is achieved where the assumed electron distribution used in the x‐ray derivations is a reasonable approximation to the measured distribution. The PIXIE data show an energy dispersion in the precipitating electrons in the morning sector such that energy increases with increasing MLT, the result of the dependence of the electron drift speed on energy and its dominance over the loss rate due to precipitation. Strong pitch angle diffusion in the morning sector depletes the source of injected electrons creating the absence of significant electron fluxes, and thus x‐ray fluxes, above 1.5 keV in the afternoon sector.
Chorus source locations from VLF Poynting flux measurements with the Polar spacecraft
Authors: LeDocq M. J. , Gurnett D. A. , Hospodarsky G. B.
Published: February 2004

Previous studies have used indirect evidence to argue that whistler‐mode chorus emissions are generated near the magnetic equator. In this paper a spatial survey of wave normals and Poynting vectors computed from three‐component electric and magnetic field measurements is used to show that chorus is generated very close to the magnetic equator. One surprising result is that there are almost no chorus emissions propagating toward the magnetic equator, such as might be expected from high‐latitude magnetospheric reflections. The absence of a reflected component indicates that the chorus is reabsorbed, probably by Landau damping, before returning to the magnetic equatorial plane.
Biogeochemical remanent magnetization in pelagic sediments of the western equatorial Pacific Ocean
Authors: Tarduno John A. , Tian Wenlai , Wilkison Sarah
Published: February 2004

Paleomagnetic data from pelagic sediments are an important source of information on the history of the geomagnetic field. However, fundamental uncertainties about how these sediments acquire their magnetizations remain. Here we address whether biogenic magnetite, formed at depth within the sediments, can contribute to remanent magnetizations. In sediments of the western equatorial Pacific Ocean (ODP Site 805), biogenic magnetite found near the Fe‐redox boundary carries a natural remanent magnetization. Because the production of biogenic magnetite is tied to the geochemical zonation of the sediments, we call this magnetization a biogeochemical remanence. These data indicate that some pelagic sediments can continue to acquire remanence significantly after the post‐depositional lock‐in of detrital magnetic grains.
Observations of Pi2 pulsations in a near ground state magnetosphere
Authors: Sutcliffe P. R.
Published: February 2004

This paper reports on the observation of Pi2 pulsations under conditions with which they have not previously been associated, namely, extremely quiet solar wind conditions when the magnetosphere is in a near ground state. Three years of data were scanned for extremely quiet intervals on the basis of ap indices and solar wind parameters. Twenty‐four extremely quiet intervals were identified, thirteen of which contained Pi2 pulsation signatures at low latitudes. The Pi2 amplitudes were similar to those typically observed during substorm expansion phases. One interval was studied in greater detail. It exhibited other substorm signatures; however, the high latitude, negative, H‐component bay was extremely weak and spatially localized. During this interval Pi2 pulsations were also observed on the day side at low latitudes.
Oceans in the past history of Mars: Tests for their presence using Mars Orbiter Laser Altimeter (MOLA) data
Authors: Head James W. , Kreslavsky Mikhail , Hiesinger Harald , Ivanov Mikhail , Pratt Stephen , Seibert Nicole , Smith David E. , Zuber Maria T.
Published: February 2004

An ancient north polar ocean on Mars has been proposed [Parker et al., 1989] and we use MOLA data to test the hypothesis. Of the two proposed contacts/shorelines, the younger Contact 2 shows the closest approximation to an equipotential surface; vertical variations along this surface occur in areas with post‐contact‐formation geological activity or suspected changes in the position of an equipotential surface (e.g., Tharsis) with time. The surface of Mars is smoother at all scales below Contact 2 than above. The volume of the region below Contact 2 (∼1.5×107 km³) is between the minimum estimated total outflow channel discharge and the maximum estimated megaregolith pore space. These results are consistent with the hypothesis that a large standing body of water occupied the northern lowlands in the past history of Mars.
A wind‐driven gradient drift mechanism for mid‐latitude E‐region ionospheric irregularities
Authors: Kagan Ludmila M. , Kelley Michael C.
Published: February 2004

We propose a new explanation for medium‐ to small‐scale irregularities in the mid‐latitude E region. We show that the very wind field that forms thin layers of ionization can also create plasma instabilities. To date, the application of gradient drift instability theory has been restricted to free energy sources involving the ambient electric field. We show that a vertical shear in the zonal wind not only leads to layer formation, but also to unstable regions on both sides of the layer. The mechanism thus does not suffer from the problem inherent in electric field‐driven processes, namely, that the mapping of electric fields along magnetic field lines leads to stabilizing conditions on one side of the layer, even if the other side is unstable. Evidence is given that anomalous diffusion due to such waves affects the evolution of the layers.
First detection of a terrestrial MeV X‐ray burst
Authors: Foat J. E. , Lin R. P. , Smith D. M. , Fenrich F. , Millan R. , Roth I. , Lorentzen K. R. , McCarthy M. P. , Parks G. K. , Treilhou J. P.
Published: February 2004

We report the first detection of a terrestrial X‐ray burst extending up to MeV energies, made by a liquid‐nitrogen‐cooled germanium detector (∼2 keV FWHM resolution) on a high‐altitude balloon at 65.5° magnetic latitude (L=5.7) in the late afternoon (1815 MLT) during low geomagnetic activity. The burst occurred at 1532–1554 UT on August 20, 1996, and consisted of seven peaks of ∼60–90 s duration, spaced by ∼100–200 s, with quasi‐periodic (∼10–20 s) modulation of the peak count rates. The very hard X‐ray spectrum extends to the instrumental limit of 1.4 MeV, and is consistent with bremsstrahlung emission from monoenergetic, ∼1.7 MeV, precipitating electrons. Since the trapped relativistic electrons showed a steeply falling energy spectrum from 0.6 to 4 MeV (at L=6.6), the precipitation mechanism appears to be highly energy selective. The modulation frequencies suggest scattering of the MeV electrons due to gyro‐resonance with Doppler‐shifted electromagnetic ion cyclotron waves, but either equatorial proton densities a factor of ∼10² higher than typical for the plasmasphere or significant O+ densities would be required.
Two point observation of high‐latitude reconnection
Authors: Šafránková J. , Němeček Z. , Sibeck D. G. , Přech L. , Měrka J. , Santolík O.
Published: February 2004

Reconnection on the high‐latitude magnetopause can produce sunward plasma flow in a portion of the lobes. This plasma should precipitate into the polar cap, poleward of the locations where magnetosheath plasma is normally found. We present two point INTERBALL observations of reconnection which is qualitatively consistent with the antiparallel merging model. Reconnection creates a plasma layer about 1RE thick adjacent to the magnetopause (MP). Timing considerations suggest tailward motion of the reconnection site with a velocity ∼20 km/s and a reconnection site with dimensions on the order of 1 RE.
An ocean model's response to North Atlantic Oscillation‐like wind forcing
Authors: Visbeck Martin , Cullen Heidi , Krahmann Gerd , Naik Naomi
Published: February 2004

The response of the Atlantic Ocean to North Atlantic Oscillation (NAO)‐like wind forcing was investigated using an ocean‐only general circulation model coupled to an atmospheric boundary layer model. A series of idealized experiments was performed to investigate the interannual to multi‐decadal frequency response of the ocean to a winter wind anomaly pattern. Overall, the strength of the SST response increased slightly with longer forcing periods. In the subpolar gyre, however, the model showed a broad response maximum in the decadal band (12–16 years).
Observation of isolated structures of the low latitude boundary layer with the INTERBALL/tail probe
Authors: Vaisberg O. L. , Smirnov V. N. , Avanov L. A. , Waite J. H. , Burch J. L. , Russell C. T. , Skalsky A. A. , Dempsey D. L.
Published: February 2004

We analyze the structure of magnetospheric transients observed at the dusk‐side low‐latitude magnetopause with the Interball Tail Probe. Ion and magnetic field measurements are used to investigate one particular transient in more detail. This transient has distinct non‐symmetric structure with the plasma characteristics and the flow properties of the leading part of the transient being quite different from those in the trailing part of the transient. The region separating these two parts corresponds to the change of the sign in the Bn component. These observations support an earlier conclusion that some plasma irregularities within the Low Latitude Boundary Layer (LLBL), formed as a result of sporadic reconnection, disconnect from the magnetopause, propagate and dissipate in the magnetosphere, and form what we call Disconnected Magnetosheath Transfer Events (DMTEs).
Perturbation of the aerosol layer by aviation‐produced aerosols: A parametrization of plume processes
Authors: Kärcher B. , Meilinger S. K.
Published: February 2004

The perturbation of the sulfate surface area density in the tropopause region and the lower stratosphere by subsonic and supersonic aircraft fleets is examined. The background aerosol surface area, the conversion of fuel sulfur into new sulfate particles in aircraft plumes, and the plume mixing with ambient air control this perturbation. Results from an analytic expression for the surface area changes are presented which contains the dependences on these parameters and can be employed in large‐scale atmospheric models.
Stable isotope fractionation during ultraviolet photolysis of N2O
Authors: Rahn Thom , Zhang Hui , Wahlen Martin , Blake Geoffrey A.
Published: February 2004

The biogeochemical cycling of nitrous oxide plays an important role in greenhouse forcing and ozone regulation. Laboratory studies of N2O:N2 mixtures irradiated between 193–207 nm reveal a significant enrichment of the residual heavy nitrous oxide isotopomers. The isotopic signatures resulting from photolysis are well modeled by an irreversible Rayleigh distillation process, with large enrichment factors of ε15,18(193 nm) = −18.4,‐14.5 per mil and ε15,18(207 nm) = −48.7,‐46.0 per mil. These results, when combined with diffusive mixing processes, have the potential to explain the stratospheric enrichments previously observed.
An automatic orbital tuning method for paleoclimate records
Authors: Yu Z. W. , Ding Z. L.
Published: February 2004

The recognized linkage of climatic events to the Earth's orbital variations has provided the basis for establishing time scales of Pleistocene climatic records. Most of the classic orbital tuning methods developed so far, however, need visual judgements to add new time control points into the climatic records, thus being time‐consuming and hindering the construction of high resolution climatic time series. In this study, we propose to use the Dynamic Optimization method to overcome the shortcomings. With this technique, the additional time control points can be automatically added into the climatic records, and a “best” age for each of the climatic data can be calculated. Results of a case study conducted on the Baoji loess section show that the automatic orbital tuning method can lead to a much better agreement of climatic time series with theoretical changes in the orbital elements relative to the classic ones.
The spectral effects of clouds on solar irradiance
Authors: Bartlett Jasmine S. , Ciotti Áurea M. , Davis Richard F. , Cullen John J.
Published: February 2004

Knowledge of the spectral attenuation associated with clouds is important for accurate estimates of natural irradiance at the Earth's surface. We compare spectral measurements of visible downwelling irradiance, under varying sky conditions at Halifax, Nova Scotia, Canada, with results from a clear‐sky model. The spectral effect of clouds is estimated by taking the ratio of the measurements to the modeled irradiances and removing spectrally consistent instrumental effects and errors in the model. Empirical relationships derived between the spectral cloud effect and both CF, the cloud factor (the ratio of measured to modeled irradiances at 490 nm), and ƒ, the fraction of sky covered by cloud, were found to follow a wavelength (λ) dependence of the form a(CF or ƒ) + b(CF or ƒ)( λ/490)−4 in the 412–700 nm wavelength range. Both this relationship and a previously published linear relationship were found to be inadequate for describing cloudy irradiance data from the Bering Sea, indicating that the spectral effect of clouds can vary with cloud type and location. We show here that the spectral cloud effect can be mimicked by using a clear‐sky model and changing the magnitude of the sky reflectivity or the spectral shape and magnitude of the ground albedo within the model. An investigation of the effects of cloud‐dependent changes in irradiance spectra on calculations of bio‐optical properties is also presented. Estimates of chlorophyll concentration from near‐surface radiances are found to vary by up to 30%, whereas the effects on estimates of photosynthetically available and usable radiation at the sea surface are negligible.
Distribution of total carbonate and related properties in the North Pacific along 30°N
Authors: Ono Tsuneo , Watanabe Shuichi , Okuda Kuniaki , Fukasawa Masao
Published: February 2004

Cross sections of the total carbonate (TC), titration alkalinity (TA), and pH were observed during the WOCE/JGOFS‐P2 cruise (30°N, 130°E –122°W). The increases in TC in the years since 1973 are calculated by the comparison of TC data observed during P2 and those observed during the Geochemical Ocean Section Study. At stations east of 170°W, TC has increased proportionally to the atmospheric increase of CO2 in water shallower than the σθ = 26.20 density surface, while at stations west of 180°E TC had increased proportionally to the atmospheric increase only in water shallower than the σθ = 25.40 density surface. Increase in the column inventory of TC is 143±32 gC/m2 on average and does not significantly differ with longitude.