bluuebunny/crossref_metadata_2025 huggingface dataset:
Response surface method for probabilistic assessment of metal forming failures
Authors: Kleiber Michał , Knabel Jarosław , Rojek Jerzy
Published: April 2004

Methodology developed for reliability calculations of structures is applied to estimate reliability of sheet metal forming operations. Sheet forming operations are one of the most common technological processes but the tool and process design is still a difficult engineering problem. Product defects are encountered in industrial practice, with forming limit diagrams (FLD) typically used as a criterion of material breakage in the manufacturing process. An FLD is a graphic illustrating the limits of the principal strains which can occur without failure in a particular forming process and particular sheet material. Principal strains obtained for a particular process are compared with the forming limit curve (FLC). An FLC is a boundary between the strain combinations which produce localized necking and/or fracture (points above FLC) and those that are permissible for the forming operation (points below FLC) which limit the safe zone.

Sheet forming operations are characterized by a significant scatter of the results. This can be caused by differences that can occur in the forming of each part. Because of uncertainties inherent in the forming process, a marginal zone is usually introduced in the FLD (5–10% below the FLC) where failure can occur with some probability. A zone of a FLD where good results are guaranteed with sufficient probability is considered as a safe zone.

In this paper we adopt a more rational (quantitative) approach to assessment of sheet metal failure during the forming operation than the intuitive approach currently in use. The methodology of reliability theory proves useful for studying the influence of parameters characterizing a forming process like friction parameters, material properties, thickness and blankholding force. The effective response surface method (RSM), developed for reliability calculations of structures, is used to estimate the reliability of sheet forming operations. Results estimated by RSM are compared with the probability of failure assessment using the advance Monte Carlo (AMC) simulation technique. Although AMC usually provides good results, the method requires many simulations and can only be applied to relatively small examples. A gradient method combined with the response surface technique is adequate for bigger problems. An example of practical significance is presented as an illustration of the approach discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Irradiation effects on the relaxation behaviour of EPDM elastomers
Authors: Celette Nathalie , Stevenson Isabelle , David Laurent , Davenas Joël , Vigier Gérard , Seytre Gérard
Published: April 2004

γ‐irradiation of ethylene–propylene diene monomer (EPDM) elastomers under oxidant atmosphere was carried out in order to change their mechanical and dielectric behaviour. Three different formulations of EPDM (70 wt% ethylene, 28 wt% propylene; diene monomer: 2 wt% norbornene) were studied: a non‐crosslinked EPDM terpolymer, a crosslinked EPDM and a crosslinked EPDM stabilized with an antioxidant. Dielectric and mechanical relaxation show a β‐sub‐glass relaxation at about −120 °C (1 Hz) and an α‐relaxation at −15 °C (1 Hz) associated with the glass transition but influenced by the effects of irradiation. The local mobility associated with the β‐relaxation is only weakly influenced by γ‐irradiation up to 450 kGy. The α‐process is shifted to higher temperatures as a result of crosslinking and changes in the semicrystalline structure. The amplitude of the dielectric α‐process increases as a result of the formation of oxidized species during irradiation under oxygen. In contrast, the mechanical α‐relaxation amplitude decreases as a result of physical and chemical cross‐linking. It was shown that the main factors that determine the crosslinking/chain scission balance are (1) the presence of oxygen together with the irradiation dose, (2) the dose rate and (3) the initial crosslink density of the EPDM material. As a result, the individual contribution of crosslinking and crystallization, and therefore the understanding and prediction of the properties after γ‐irradiation can only be deduced after comparison of the polymer behaviour below and above its melting temperature. Copyright © 2004 Society of Chemical Industry
Coordination of nickel and copper dithiolate to 2,2′‐bipyridine‐based π‐conjugated polymers
Authors: Kato Shin‐ichiro , Takagi Koji , Suzuki Kirito , Kinoshita Takatoshi , Yuki Yasuo
Published: April 2004

π‐Conjugated polymers (Poly1–Poly3) containing a 2,2′‐bipyridine (bpy) unit were subjected to coordination to nickel and copper dithiolate for the purpose of manipulating the photophysical properties. The absorption maximum peak of Poly1 [maximum wavelength (λmax) = 446 nm] redshifted by 36 nm upon the coordination of bpy to NiCl2, which produced Poly1–NiCl2. A further bathochromic shift was observed in the spectrum of Poly1–mntNi [mntNi = (maleonitrile dithiolate)nickel; λmax = 499 nm] bearing the dithiolate ligand, which stemmed from the extension of the conjugated system over the nickel dithiolate moiety through the bpy unit. An increase in the [Ni]/[bpy] ratio in Poly1–mntNi rendered the original maximum peak at 446 nm smaller and the lower energy charge‐transfer peak at 499 nm larger; the isosbestic points remained at 380 and 475 nm. The green fluorescence (λmax = 504 nm) emitted from Poly1 markedly diminished upon the coordination of nickel dithiolate because of the effective energy transfer. The absorption maximum peak of Poly1–mntNi in chloroform at 499 nm blueshifted to 471 nm when the volume ratio of the chloroform/N,N‐dimethylformamide solvent reached 10:90. The coordination of nickel dithiolate to Poly2 and Poly3 also brought about redshifts of the absorption maximum peaks of as much as 55 and 61 nm, respectively. The absorption maximum peak of Poly1–(phenyldithiolate)nickel(pdtNi) (λmax = 474 nm) redshifted by 28 nm in comparison with that of Poly1, whereas the magnitude of the shift of Poly1–bis(thiophenoxide)nickel(btpNi) bearing two thiophenoxide ligands was 20 nm. Poly1–mntCu with a tetrahedral copper center was also investigated. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2631–2639, 2004
Studies on structure and conformational stability of free canonical 2′‐deoxyribonucleosides: Approximate SCC‐DFTB and LMP2 methods
Authors: Kolandaivel P. , Knapp‐Mohammady Michaela , Suhai Sandor
Published: April 2004

The molecular structure of free canonical 2′‐deoxyribonucleosides have been studied by applying the electron‐correlated local second‐order Møller–Plesset perturbation theory (LMP2) and self‐consistent‐charge density‐functional tight‐binding (SCC‐DFTB) methods. The variation of structural parameters for C2, C3 endo and exo conformations, and anti, syn orientation of the base unit with furanose ring have been discussed. The relative energies have been calculated for the anti and syn conformations of dT, dC, dG, and dA. Conformational analysis has been performed using the results of the LMP2 and SCC‐DFTB methods. Chemical hardness and chemical potential have been used to study the conformational stability of the conformers. The maximum hardness principle is obeyed for the furanose ring conformations and not for the nucleosides. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Contextual family therapy with the victims of incest
Authors: Lutz Susan E. , Medway Joan P.
Published: April 2004

The authors apply the concepts of Boszormenyi‐Nagy's contextual family therapy to the family treatment of victims of incest. Intergenerational bonds of loyalty and indebtedness are stressed, as is the therapist's goal of increasing mutual empathy between the victim and the victimizer. Case examples are provided.
The first 100 admissions to a regional general purpose adolescent unit
Authors: Ainsworth Patricia
Published: April 2004

Details are presented of the first 100 admissions to a regional “general purpose” psychiatric unit for adolescents. Seventy‐seven per cent had been referred from other consultants, including 51 per cent from child and adolescent psychiatrists. There was a high incidence of family disruption and disharmony. Apart from a small group of “organic” problems (eight) they were evenly distributed between four major diagnostic groupings: psychotic disorder, conduct disorder, neurotic disorder and mixed conduct/neurotic disorder. Use was made of a variety of treatment approaches and the best outcomes were in the neurotic group (81 per cent some or much improved at discharge) and the psychotic group (68 per cent some or much improved). Attention is drawn to the high rate of “premature” discharge (41 per cent) including 18 per cent expelled because of their behavior. Nearly 50 per cent of these fell in the conduct disorder group and there are obvious implications for the selection process.
Adolescents and alcohol—a review of the recent British research
Authors: Sharp Deborah J. , Lowe G.
Published: April 2004

There is evidence of increased alcohol consumption by young people. This review concentrates on the British epidemiological and psychological studies of adolescent drinking behaviour, with special reference to the cultural and developmental aspects. It is clear that drinking alcohol may be considered a normal part of adolescence and many young people are introduced to it by their parents. However, one area of concern is the amount of drunkenness reported. The way forward is to gain new insights into what drinking means to adolescents and how such meanings are propagated.
Social cognitive skills and behavioural adjustment of delinquent adolescents in treatment
Authors: Hains Anthony A. , Herrman Leo P.
Published: April 2004

Social cognitive skills (i.e. problem‐solving, self‐control, locus of control, rational attributions) were examined in aggressive and non‐aggressive delinquent youths at two levels of behavioural functioning (high versus low). Behavioural functioning was defined in terms of the youths' standing within a 10‐level behavioural token economy programme. Inventories and question‐naires were used to measure the skills of interest. A significant interaction was found on problem‐solving skills, with higher functioning, non‐aggressive youths performing better than their lower functioning counterparts, while no differences occurred within the aggressive groups. No differences were obtained on the other measures.
Death related themes in anorexia nervosa: a practical exploration
Authors: Russell Janice , Halasz George , Beumont Pierre J.V.
Published: April 2004

On the basis of an extensive literature review, Jackson and Davidson (1986) suggested that the theme of death may constitute an integral part of the psychodynamic aetiology of anorexia nervosa. This paper describes an attempt to explore this contention using a structured questionnaire in a group of adolescent patients to examine experiences, concepts of and attitudes concerning death. Comparison of the responses of this group with those of age matched school student controls and recovered patients revealed qualitative and quantitative differences which lent some support to the hypothesis. It is concluded that death related themes are of significance in the understanding and management of this illness.
Prevalence of psychological distress in Irish female adolescents
Authors: Brown Katherine , Fitzgerald Michael , Kinsella Anthony
Published: April 2004

Some female adolescents (N=132) attending two inner city Dublin schools completed the Youth Self Report Questionnaire (YSRQ).

Of this group 15·4 per cent obtained a Total Problem Score in the clinical range. A higher proportion, 23 per cent, obtained a score in the clinical range on one or more problem subscales of the YSRQ.

No one scored abnormally on the Social or Competence Scales. A number of interesting and thought provoking responses to individual questions were obtained.

The possible clinical relevence of these findings and implications for future planning in schools are discussed.
Process issues in consultancy
Authors: Reed Chris , Greer Anne , McKay Cathy , Knight Christine
Published: April 2004

A piece of short term consultancy work in a school for the Mentally Handicapped is described from the perspective of both the consultants and the consultees with particular reference to the process issues involved. Reasons for the high levels of stress experienced in the exercise are explored by an examination of the contributory factors within the school and the consultancy process itself. As well as a theoretical discussion questions of practical management are considered.
Routine medical examinations: a problem audited is a problem solved
Authors: Jaffa Tony , Bruggen Peter
Published: April 2004

Staff had difficulty in gaining the co‐operation of adolescents for routine medical examinations in an in‐patient unit. This was largely resolved by giving more explanation to the adolescent and, in cases of difficulty, calling a meeting of other patients and staff.
Daisybank 1983–1989. An audit of a residential home preparing adolescents for permanent placements
Authors: Levinson Margot , Minty Brian
Published: April 2004

This paper describes the evaluation of a small children's home, Daisybank, set up to prepare adolescents, who had been in care for several years, to live in permanent placements. The home seemed largely to fail in this explicit task, but appear to succeed in helping a majority of its residents make substantial progress in coming to terms with their deprived and disrupted lives. It provided them with genuine care and commitment, which they acknowledged and appreciated. We believe that the success of the home needs to be judged by these criteria, since for young people in mid‐ to late adolescence the search for new permanent parental homes probably conflicted with other psychosocial tasks relating to adolescence. On the other hand, Daisybank seemed unable adequately to resolve the problems of a subgroup of adolescent males with serious conduct problems who were responsible for the not infrequent physical abuse of several female staff.
Rhamnogalacturonan lyase reveals a unique three‐domain modular structure for polysaccharide lyase family 4
Authors: McDonough Michael A. , Kadirvelraj Renuka , Harris Pernille , Poulsen Jens-Christian N. , Larsen Sine
Published: April 2004

Rhamnogalacturonan lyase (RG‐lyase) specifically recognizes and cleaves α‐1,4 glycosidic bonds between l‐rhamnose and d‐galacturonic acids in the backbone of rhamnogalacturonan‐I, a major component of the plant cell wall polysaccharide, pectin. The three‐dimensional structure of RG‐lyase from Aspergillus aculeatus has been determined to 1.5 Å resolution representing the first known structure from polysaccharide lyase family 4 and of an enzyme with this catalytic specificity. The 508‐amino acid polypeptide displays a unique arrangement of three distinct modular domains. Each domain shows structural homology to non‐catalytic domains from other carbohydrate active enzymes.
“We Might be Trusted”: Female Poor Law Guardians and the Development of the New Poor Law: The Case of Bolton, England, 1880–1906
Authors: King Steven
Published: April 2004

This article uses the only surviving working diary of an English female Poor Law guardian in the late nineteenth and early twentieth centuries to explore two interrelated bodies of historiography. First, it engages with an historiography of the New Poor Law which has by and large seen the late nineteenth century as a period of atrophication. Second, it engages with a literature on female Poor Law guardians which has on balance questioned their achievements and seen such women as subject to all sorts of conflict and discrimination. The article argues that both perspectives may be questioned where we focus on local Poor Law policies and local women. Using the example of Bolton, in England, it is argued that the boards of Poor Law unions were riven by fracture lines more important than gender. Within this context, women of relatively high social status were able to manipulate the Poor Law agenda to make substantial changes to the policy and fabric of the late Victorian Poor Law. Rather than conflict, we often see a warm appreciation of the pioneering work of female Poor Law guardians.
Leading the White-Collar Union: Clive Jenkins, the Management of Trade-Union Officers, and the Politics of the British Labour Movement, c.1968–1979
Authors: Melling Joseph
Published: April 2004

The growth of white-collar unionism and its impact on British trade unions in the postwar period has received little attention from social historians. Radical critics have noted the failure of Clive Jenkins to provide a clear lead in defending workers' conditions, while mainstream, institutionalist commentators more often stress the diversity of specific interests served by such unions. Recent research has called into question earlier models of union governance, though there remain few studies of the history of officer relations within trade unions. This article examines the leadership of ASTMS in the decade after its formation. It is argued that the strategies pursued by Jenkins, including the recruitment, training, and deployment of fieldworkers, were guided by accumulated knowledge and culture (as well as brilliant opportunism) rather than by the structure of the union or the composition of the membership. In offering educated officers a career structure, ASTMS increased its capacity for expertise and effective communication without descending into the political sectarianism of the postwar years. The charismatic, capricious style adopted by Jenkins, as well as the difficulties of absorbing a diverse membership in this period of rapid growth, contributed to the tensions which culminated in a series of struggles between the union and its bargainers during the 1970s.
Dynamics of Contention
Authors: The Editors
Published: April 2004

In 2001, Doug McAdam, Sydney Tarrow, and Charles Tilly published Dynamics of Contention. In this jointly written volume, they aim to identify “similarities and differences, pathways and trajectories across a wide range of contentious politics – not only revolutions, but also strike waves, wars, social movements, ethnic mobilizations, democratization, and nationalism”. Thereby, they set out to develop the foundations for a general programme for the study of contentious episodes wherever and whenever they occur.

As Dynamics of Contention is an ambitious work in the field of historical sociology and social history, we have invited comments by Knut Kjeldstadli, Dilip Simeon, and Thomas Welskopp – scholars from different research traditions. Charles Tilly responds.
Crossing the Boundaries? Dynamics of Contention Viewed from the Angle of a Comparative Historian
Authors: Welskopp Thomas
Published: April 2004

Comparative social history is still grappling with the problems raised in the debate about history's “cultural turn”. And while a new “social turn” seems imminent at the moment, this means a new departure into an actor-oriented analysis of institutions (including social movements and all forms of contentious politics) beyond the “cultural turn”, incorporating a host of compelling insights into the cultural constitution of social reality – and not a return to the old simplistic views of the “modernization era”.
Stories of Saints and Sultans: Re-membering History at the Sufi Shrines of Aurangabad
Authors: GREEN NILE
Published: April 2004

Encounters between Sufi saints and Muslim rulers have played a long and important role in the textual historical traditions of Muslim South Asia. Historians of the sultanates of Delhi and the Deccan writing in Persian such as Ziya al-din Barani and Abu'l Qasim Firishtah peppered their accounts with such narratives, much to the distaste of their nineteenth century British translators who frequently excised such episodes wholesale. Some of the earliest Sufi literature composed in South Asia, such as the ‘recorded conversations’ (malfuzat) written in the circle of Nizam al-din Awliya of Delhi (d.725/1325), make clear the importance of this topos of the interview between the saint and king. The actual historical nature of such encounters is sometimes difficult to ascertain in view of the didactic and moralizing dimensions to both medieval historiography and Sufi literature in Persian.
Hong Kong and the Pearl River Delta Qiaoxiang
Authors: Williams Michael
Published: April 2004

In the history of links between people from the Pearl River Delta with the countries of South-East Asia and the Pacific, the role played by Hong Kong cannot be ignored. It is the purpose here to examine the role and contribution of Hong Kong to these Pearl River Delta links over the period 1842 to 1942. Such an examination, it is hoped, will also allow the impact of Pearl River Delta links on Hong Kong to be investigated. Much of the material presented by this paper is not new, rather the aim is to view Hong Kong from the perspective of the Pearl River Delta qiaoxiang. A perspective, it is suggested, that will enable aspects of Hong Kong's history and its contribution to the history of the Pearl River Delta counties and their overseas links to be seen in a new way.
‘Stranger within the Gates’: Knowing Semi-Colonial Siam as Extraterritorials
Authors: Lysa Hong
Published: April 2004

Siam and the Semi-colonial Issue

The issue of Siam as a semi-feudal, semi-colonial social formation, mooted by Thai Marxists in the 1950s, and again in the 1970s, has by the 1990s by and large been set aside by critically-minded academics for its inability to provide a lineage for the strain of capitalist mode of production that has emerged by the second half of the twentieth century. Nevertheless, the ‘semi-colonial’ as an analytical framework retains its force in confronting the assumed independence and an unreflexive racially based elite nationalism that has so defined Thai self-representations and public culture, but also in how Thailand is understood by others.
A hell of a choice: reply to Talbott
Authors: WALLS JERRY L.
Published: April 2004

In this article I respond to Thomas Talbott's criticisms of the view of hell I have defended. In particular, I argue that coherent sense can be made of the choice to be eternally separated from God. Moreover, Talbott does not successfully show how God can save everyone without overriding their freedom. Finally, I argue that there is no significant sense in which sinners defeat God or sin with impunity on the view I have defended. Talbott's case that universalism necessarily follows from God's perfect love and power then fails.
GPS/INS Enhancement for Land Navigation using Neural Network
Authors: Kaygisiz Burak H. , Erkmen Ismet , Erkmen Aydan M.
Published: April 2004

We propose in this paper a method to enhance the performance of a coupled global positioning/inertial navigation system (GPS/INS) for land navigation applications during GPS signal loss. Our method is based on the use of an artificial neural network (ANN) to intelligently aid the GPS/INS coupled navigation system in the absence of GPS signals. The proposed enhanced GPS/INS is tested in the dynamic environment of a land vehicle navigating around a closed path on the METU campus and we provide the results. Our GPS/INS+ANN system performance is thus demonstrated with a land trial.
The polycontextual nature of computer-supported learning – theoretical and methodological perspectives
Authors: SAARENKUNNAS MAARIT , KUURE LEENA , TAALAS PEPPI
Published: April 2004

This article discusses some theoretical and methodological problems and issues in the study of computer-supported
learning activities with special reference to a discourse perspective in research. Special emphasis is laid on finding ways to reach
the participant perspective in computer-supported collaborative learning projects, which are by nature polycontextual. By this term we
refer to the diverse scenes and situations of learning activities that computer-supported learning involves. We will also address the
issue of making claims on effective pedagogies, leaning on the theory of discourse as situated and constructive, which again sets
special requirements on what kinds of assumptions and interpretations can and should be derived through empirical analysis of data.
Instead of rushed normative guidelines for instruction we should now take time and examine critically what is really happening in
computer-supported environments in real-life situations. A look at the particular is needed. An important question to examine, for example,
is how students and teachers use these tools in their everyday lives and how these processes are talked about. We will discuss through
a number of examples the multimodal and polycontextual nature of meaning making in participant activities during three different
university language courses between 1998–2002. This article considers relevant research approaches with the aid of theoretical
discussion and examples of analysis.
On Positive Maps, Entanglement and Quantization
Authors: Majewski Władysław A.
Published: April 2004

We outline the scheme for quantization of classical Banach space results associated with some prototypes of dynamical maps and we describe the quantization of correlations. A relation between these two areas is discussed.
The Influence of Quantum Degeneracy on the Performance of a Fermi Brayton Engine
Authors: Lin Bihong , Chen Jincan
Published: April 2004

The influence of quantum degeneracy on the performance of a Brayton engine using an ideal Fermi gas as the working substance is investigated, based on the theory of statistical mechanics. The general expressions of the efficiency and work output of the engine cycle are derived. The maximum work output and the corresponding efficiency are calculated. The bound of the pressure ratio of the two constant-pressure processes that the Brayton engine cycle can be operated normally is determined. Some important characteristic curves of the cycle, such as the work output versus pressure ratio curves, the efficiency versus pressure ratio curves, the maximum work output ratio versus temperature of the heat reservoirs curves, and so on, are presented. Three special cases are discussed in detail. The results obtained may reveal the general performance characteristics of a Brayton engine working with an ideal Fermi gas.
Beurteilerübereinstimmung und Beurteilerstrenge
Authors: Eckes Thomas
Published: April 2004

Zusammenfassung. Leistungsbeurteilungen unterliegen einer Reihe von Urteilsfehlern, die ihre Genauigkeit und Validität erheblich mindern können. Ein besonders kritischer Urteilsfehler ist die Tendenz zur Strenge bzw. Milde. In der vorliegenden Arbeit wird mit der Multifacetten-Rasch-Analyse (“many-facet Rasch measurement“; Linacre, 1989 ; Linacre & Wright, 2002 ) ein Item-Response-Modell vorgestellt, das Messungen der Strenge bzw. Milde eines jeden Beurteilers erlaubt und die ermittelten Strengemaße zusammen mit den Fähigkeitsmaßen der beurteilten Personen und den Schwierigkeitsmaßen der Aufgaben oder Beurteilungskriterien in einen gemeinsamen Bezugsrahmen stellt. Das Modell ermöglicht ferner eine um die Strenge der Beurteiler korrigierte Leistungsmessung. Mittels dieses Ansatzes werden im Rahmen des “Test Deutsch als Fremdsprache“ (TestDaF) Beurteilungen analysiert, die je 2 von insgesamt 29 Beurteilern zu Leistungen von 1359 Pbn im schriftlichen Ausdruck nach 3 Kriterien abgegeben haben. Die Gruppe der Beurteiler erweist sich als sehr heterogen, so dass eine Strengekorrektur der Urteile geboten ist. Abschließend werden verschiedene Implikationen des Multifacetten-Rasch-Modells für die Evaluation von Leistungsbeurteilungen diskutiert.
Eating Disorder Examination: Deutschsprachige Version des strukturierten Essstörungsinterviews
Authors: Hilbert Anja , Tuschen-Caffier Brunna , Ohms Martina
Published: April 2004

Zusammenfassung. Das Eating Disorder Examination (EDE) von Fairburn und Cooper (1993) ist ein strukturiertes Essstörungsinterview zur Erfassung der spezifischen Psychopathologie von Essstörungen. In der klinischen Forschung und Praxis gilt es weithin als Methode der Wahl für die Essstörungsdiagnostik. Die in diesem Beitrag vorgestellte deutschsprachige, reübersetzte Version des EDE zeigte in Stichproben von 80 Patientinnen mit Bulimia Nervosa, 144 Patientinnen mit Binge-Eating-Störung und 20 Patientinnen mit Anorexia Nervosa hohe Interrater-Reliabilitäten der Items sowie der Subskalen. Als Indikatoren für die konvergente Validität waren die EDE-Subskalen Shape Concern und Weight Concern mit Selbstbeurteilungsskalen zum Körperbild, z.B. dem Fragebogen zum Figurbewusstsein, hoch korreliert. Die EDE-Subskalen Restraint und Eating Concern zeigten signifikante Zusammenhänge mit dem in Ernährungstagebüchern protokollierten Essverhalten, z.B. Mahlzeiten- oder Essanfallshäufigkeit oder Nährstoffaufnahme. Die Subskalen des EDE unterschieden zwischen Gruppen mit verschiedenen Essstörungsdiagnosen und bildeten Veränderungen durch psychologische Psychotherapie sensitiv ab. Somit steht mit der deutschsprachigen Version des EDE ein dem englischsprachigen Original entsprechendes, geeignetes Instrument für die Erfassung der spezifischen Psychopathologie von Essstörungen zur Verfügung.
Evidence for the submarine weathering of silicate minerals in Black Sea sediments: Possible implications for the marine Li and B cycles
Authors: Aloisi G. , Wallmann K. , Drews M. , Bohrmann G.
Published: April 2004

The role of sediment diagenesis in the marine cycles of Li and B is poorly understood. Because Li and B are easily mobilized during burial and are consumed in authigenic clay mineral formation, their abundance in marine pore waters varies considerably. Exchange with the overlying ocean through diffusive fluxes should thus be common. Nevertheless, only a minor Li sink associated with the low‐temperature alteration of volcanic ash has been observed. We describe a low‐temperature diagenetic environment in the Black Sea dominated by the alteration of detrital plagioclase feldspars. Fluids expelled from the Odessa mud volcano in the Sorokin Trough originate from shallow (≈100–400 m deep) sediments which are poor in volcanic materials but rich in anorthite. These fluids are depleted in Na+, K+, Li+, B, and 18O and enriched in Ca2+ and Sr2+, indicating that anorthite is dissolving and authigenic clays are forming. Using a simple chemical model, we calculate the pH and the partial pressure of CO2 (PCO2) in fluids associated with this alteration process. Our results show that the pH of these fluids is up to 1.5 pH units lower than in most deep marine sediments and that PCO2 levels are up to several hundred times higher than in the atmosphere. These conditions are similar to those which favor the weathering of silicate minerals in subaerial soil environments. We propose that in Black Sea sediments enhanced organic matter preservation favors CO2 production through methanogenesis and results in a low pore water pH, compared to most deep sea sediments. As a result, silicate mineral weathering, which is a sluggish process in most marine diagenetic environments, proceeds rapidly in Black Sea sediments. There is a potential for organic matter‐rich continental shelf environments to host this type of diagenesis. Should such environments be widespread, this new Li and B sink could help balance the marine Li and Li isotope budgets but would imply an apparent imbalance in the B cycle.
First ground‐based OI 630 nm optical measurements of daytime cusplike and F‐region auroral precipitation
Authors: Pallamraju D. , Chakrabarti S. , Doe R. , Pedersen T.
Published: April 2004

We have used a high‐resolution (0.012 nm at 630 nm) imaging spectrograph to measure auroral emissions in daytime along the magnetic meridian from Sondrestrom Incoherent Scatter Radar (ISR) facility, at Kangerlussuaq, Greenland (67°N, 51°W; 74.5°N Mag. Lat.). Measured red line (OI 630 nm) brightness during a magnetically disturbed day (January 21, 2001) shows emission enhancements starting at 1330 UT (1130 MLT) and reaching a four‐fold enhancement above the normal dayglow brightness about two hours later. The onset enhancement, characterized by a sharp equatorward boundary, was measured concurrently with ISR Ne and Te, whose morphologies are generally indicative of cusplike precipitation. The 630 nm emission enhancements after 1518 UT correspond to a series of post‐noon F‐region arcs as measured by the ISR. Modeled 630 nm airglow brightness using ISR data, agree well with both the brightness and time history of the daytime optical measurements.
Lower‐hybrid cavity density depletions as a result of transverse ion acceleration localized on the gyroradius scale
Authors: Knudsen D. J. , Bock B. J. J. , Bounds S. R. , Burchill J. K. , Clemmons J. H. , Curtis J. D. , Eriksson A. I. , Koepke M. E. , Pfaff R. F. , Wallis D. D. , Whaley N.
Published: April 2004

We explore a mechanism by which density depletions associated with lower‐hybrid cavities and similar structures are a direct consequence of ion trajectories resulting from transverse energization localized on scales comparable to the ion gyroradius. Specifically, a heating region localized to a flux tube having a diameter of the order of a few ambient thermal ion gyroradii will be depleted of ions because of heated‐gyroradius‐scale excursions of the ions away from the heating region. Cooler ions outside will have smaller average gyroradii and will be unable to compensate for the depletion inside the heating region. The outflux of energized ions from the heated region results in a density enhancement at its periphery. Motivated by space observations, we characterize density perturbations resulting from an idealized, cylindrically symmetric Gaussian temperature enhancement, using Monte Carlo simulations and an orbit‐averaged density calculation. Our model generates density depletions of the order of 10% for a two‐fold increase in Ti over the background value and 50% for a fifty‐fold increase. In addition to density depletions the model predicts density‐enhanced shoulders around cavity perimeters and shows how heated ion tails superimposed on cool ionospheric plasmas can be explained by hot, Maxwellian ions originating on nonlocal flux tubes. We present examples of shoulders observed by sounding rockets and by the Freja satellite. Finally, we use sounding rocket measurements to demonstrate that the distribution of cavity widths (or chord lengths) is relatively narrow (16 ± 10 m), with an average width that remains nearly unchanged even as plasma density varies over five orders of magnitude. This result is consistent with gyroradius being the key scaling parameter, although it does not rule out other scaling predictions that do not depend on plasma density.
Temporal and spatial aspects of the cusp inferred from local and global ground‐ and space‐based observations in a case study
Authors: Farrugia C. J. , Sandholt P. E. , Torbert R. B. , Østgaard N.
Published: April 2004

Global and local observations, from both ground and space facilities, are brought to bear to understand the origin of a stepped cusp ion dispersion observed 3 hours prenoon under an interplanetary magnetic field characterized by strongly positive By, conditions under which the cusp is believed to be shifted postnoon. Our main aim is to distinguish the temporal from the spatial cusp features. The local observations from Svalbard are from approximately the 0900–1200 MLT sector, while the in situ observations are from Polar at 0900 MLT. The global auroral observations were acquired by the Earth camera on Polar. The aurora from the ground perspective appeared as a periodic sequence of brightening events located on either side of a “midday gap aurora” centered at about 1030 MLT. At noon the aurora appeared as a semiperiodic sequence of brightening events. These were concurrent with enhancements of the overhead ionospheric Hall current. Polar observed two steps of a staircase ion energy‐latitude dispersion. These two steps were, in turn, concurrent with two consecutive auroral brightening events. We argue from this complement of observations that the stepped cusp was temporal in nature and resulted from a time‐varying reconnection process. Global UV imagery was employed to complement the ground observations for the purpose of separating the temporal from the spatial aspects. The imager captured, namely, two bands of strong UV emission in the prenoon and postnoon sectors, between which there appeared a persistent, weak UV aurora. We interpret this to be an underlying spatial substratum. Patchy and bursty UV enhancements coincided with the transients seen in the local ground and space measurements, corroborating further our distinction between space and time in the cusp. Comparing these inferences with recent work on the response of the dayside aurora to reconnection at the magnetopause, we find a close correspondence. In addition, we document the field‐aligned currents associated with the stepped cusp, which, in turn, compare favorably with recent theoretical ideas. This work is a contribution to the current debate on the nature of the stepped cusp and suggests that multiple data sets are essential to study this problem.
MHD simulations of Earth's bow shock: Interplanetary magnetic field orientation effects on shape and position
Authors: Chapman J. F. , Cairns Iver H. , Lyon J. G. , Boshuizen Christopher R.
Published: April 2004

The location and geometry of Earth's bow shock vary considerably with the solar wind conditions. More specifically, Earth's bow shock is formed by the steepening of fast mode waves, whose speed vms depends upon the angle θbn between the local shock normal n and the magnetic field vector BIMF, as well as the Alfvén and sound speeds (vA and cS). Since vms is a minimum for θbn = 0° and low Alfvén Mach number MA, and maximum for θbn = 90° and high MA, this implies that as θIMF (the angle between BIMF and vsw) varies, the magnitude of vms should vary also across the shock, leading to changes in shape. This paper presents 3‐D MHD simulation data which illustrate the changes in shock location and geometry in response to changes in θIMF and MA, for 1.4 ≤ MA ≤ 9.7 and 0° ≤ θIMF ≤ 90°. Specifically, for oblique IMF the shock's geometry is shown to become skewed in planes containing BIMF (e.g., the x − z plane). This is also emphasized in the terminator plane data, where the shock is best represented by ellipses, with centers translated along the z axis. For the θIMF = 90° simulations the shock is symmetric about the x axis in both the x − y and x − z planes. Simulations for field‐aligned flow (θIMF = 0°) show a dimpling of the nose of the shock as MA → 1. The simulations also illustrate the general movement of the shock in response to changes in MA; high MA shocks are found closer to Earth than low MA shocks. Farris et al.'s [1991] magnetopause model is used in the simulations, and we discuss the limitations of this, as well as the expected results using a self‐consistent model.
Instability of the E‐F coupled nighttime midlatitude ionosphere
Authors: Cosgrove Russell B. , Tsunoda Roland T.
Published: April 2004

Tsunoda and Cosgrove [2001] recently pointed out that the F layer and sporadic E (Es) layers in the nighttime midlatitude ionosphere must be considered electrodynamically as a coupled system in light of the presence of a Hall polarization process in Es layers [Haldoupis et al., 1996; Tsunoda, 1998; Cosgrove and Tsunoda, 2001, 2002a] and the fact that kilometer‐scale electric fields map efficiently between the E and F regions. They further noted the apparent presence of positive feedback between processes in those regions. Cosgrove and Tsunoda [2002b, 2003] have since shown that Es layers are unstable with properties not unlike those of the Perkins instability in the F region [Perkins, 1973], thus providing yet another reason to consider the behavior of the coupled system. In this paper we show mathematically that the coupled system is indeed unstable with properties that are not only related to but distinct from those of the individual instabilities. A key finding is that this coupled response significantly enhances the growth rate of F region structures, beyond that of the Perkins instability.
Fast solar wind after the rapid acceleration
Authors: Kojima M. , Breen A. R. , Fujiki K. , Hayashi K. , Ohmi T. , Tokumaru M.
Published: April 2004

We have studied the radial dependence of the velocity of high‐latitude fast solar wind in the heliocentric distance range of 0.13–0.9 AU. For this study a new tomographic analysis method which can evaluate uncertainties was developed to obtain velocity distribution maps on two reference spheres at 0.13 and 0.3 AU using interplanetary scintillation (IPS) observations. First of all, it is tested that this tomographic method has enough sensitivity and reliability to investigate the radial dependence of the wind velocity. The analysis was made for the IPS observations during 3 years, from 1995 to 1997, when solar activity was minimum. From this analysis, average velocities of 770–780 km s−1 were obtained at distances of 0.13–0.3 AU, which were 19 ± 17 km s−1 lower than those at 0.3–0.9 AU. The results from this work, taken together with measurements of SOHO/LASCO, EISCAT and MERLIN [Breen et al., 2002], Helios [Schwenn et al., 1978], and Ulysses [McComas et al., 2000], indicate that the fast wind is accelerated almost to its final flow velocity within 20 Rs and a small but not negligible acceleration exists beyond 30 Rs which tends to become smaller at farther heliocentric distances.
Reflection properties of the core‐mantle boundary from global stacks of PcP and ScP
Authors: Persh Steven E. , Vidale John E.
Published: April 2004

Seismic phases that reflect off the core‐mantle boundary (CMB) are sensitive to the velocity and density contrasts between the base of the mantle and the core. We measure the amplitudes of CMB reflections to seek effects of large velocity reductions and possible density increases in proposed thin basal layers (ultralow‐velocity zones, or ULVZs). We construct globally averaged envelope stacks of PcP and ScP in 3°‐wide epicentral distance bins, correcting for propagation and source effects. We measure the amplitude ratios PcP/P and ScP/P and compare them with the predicted range dependence for preliminary reference Earth model (PREM) and several proposed ULVZ models. The amplitude ratios are not compatible with ULVZs containing 30% S wave velocity reductions or with a 3‐km‐wide core‐mantle transition zone. The PcP data cannot distinguish between PREM and models with 10% reductions in both P wave velocity (VP) and S wave velocity (VS) and up to a 20% increase in density. The ScP data also match PREM closely but contain greater uncertainty from the correction for mantle attenuation. In well‐sampled regions, lateral variations of reflection amplitudes mapped to bounce point locations are consistent with previous detections and nondetections of ULVZs. These results suggest that extreme velocity reductions near the CMB are not global features and that regions with large velocity reductions do not result from global phenomena such as phase changes in an isochemical mantle but rather from local thermal or compositional anomalies.
Tides and sea level in the Gulf of Aqaba (Eilat)
Authors: Monismith Stephen G. , Genin Amatzia
Published: April 2004

In this paper, we discuss observations of tidal variations in currents and elevation taken in the Gulf of Aqaba (Eilat) over the fringing coral reef at Eilat, Israel. Both currents and elevations appear to be strongly affected by conditions in the main body of the Red Sea. Tidal currents, which vary considerably in strength throughout the year, appear to be associated with internal waves generated at the Strait of Tiran where density‐driven exchanges between the Gulf of Aqaba and the Red Sea take place. Water level also has significant annual and interannual variations; as seen in other studies of the Red Sea, these appear to be associated with corresponding variations in winds acting on the entire Red Sea.
Model intercomparison for the present day, the mid‐Holocene, and the Last Glacial Maximum over western Europe
Authors: Hoar Mark R. , Palutikof Jean P. , Thorne Mike C.
Published: April 2004

The focus of this paper is an evaluation of the performance over western Europe of an ensemble of General Circulation Models (GCMs) used to simulate climates at the present‐day, the mid‐Holocene and the Last Glacial Maximum (LGM). Experiments are considered from the Palaeoclimate Modeling Intercomparison Project (PMIP), and from more recent sensitivity studies for the same time slices. Surface air temperature and precipitation are compared between models, and with observed and proxy data sets, using evaluation measures such as correlation coefficients and root mean squared errors. Hierarchical and k‐means cluster analysis are used to quantitatively assess relative model performance. Comparisons are made for western Europe for a gridded domain between 38N13W (south west corner) and 65N30E (north east corner), and for four transects within this domain. Inter‐experiment comparisons reveal that the ranges of results from the sensitivity studies are within those of the PMIP models. There is no month‐to‐month or time slice‐to‐time slice consistency in the clustering patterns produced, although one clear characteristic is that experiments performed with models from the same institution tend to cluster. Inter‐model agreement at past time slices is considerably reduced when we consider differences from the present‐day rather than absolute values, and this is particularly the case for mid‐Holocene temperature, when the insolation forcing only represents a small departure from modern values. Statistical comparisons of the models with observed and proxy data sets demonstrate a lack of consistency in model performance between months, transects and time slices.
Aerosol indirect effects in POLDER satellite data and the Laboratoire de Météorologie Dynamique–Zoom (LMDZ) general circulation model
Authors: Quaas J. , Boucher O. , Bréon F.‐M.
Published: April 2004

The POLDER‐1 instrument was able to measure aerosol and cloud properties for eight months in 1996–1997. We use these observational data for aerosol concentration (the aerosol index), cloud optical thickness, and cloud droplet effective radius to establish statistical relationships among these parameters in order to analyze the first and second aerosol indirect effects. We also evaluate the representation of these effects as parameterized in the Laboratoire de Météorologie Dynamique–Zoom (LMDZ) general circulation model. We find a decrease in cloud top droplet radius with increasing aerosol index in both the model and the observations. Our results are only slightly changed if the analysis is done at fixed cloud liquid water path (LWP) instead of considering all LWP conditions. We also find a positive correlation between aerosol index and cloud liquid water path, which is particularly pronounced over the Northern Hemisphere midlatitudes. This may be interpreted as observational evidence for the second aerosol indirect effect on a large scale. The model‐simulated relationship agrees well with that derived from POLDER data. Model simulations show a rather small change in the two relationships if preindustrial rather than present‐day aerosol distributions are used. However, when entirely switching off the second aerosol indirect effect in our model, we find a much steeper slope than we do when including it.