bluuebunny/crossref_metadata_2025 huggingface dataset:
Farnesyl diphosphate synthase activity affects ergosterol level and proliferation of yeast Saccharomyces cerevisae
Authors: Karst Francis , Plochocka Danuta , Meyer Sophie , Szkopinska Anna
Published: January 2004

The yeast farnesyl diphosphate synthase (FPPS) gene was engineered so as to construct allelic forms giving various activities of the enzyme. One of the substitutions was F96W in the chain length determination region. The other, K197, conserved within a consensus sequence found in the majority of FPP and GGPP synthases, was substituted by R, E and V. An intricate correlation has been found between the FPPS activity, the amount of ergosterol synthesized and cell growth of a mutant strain defective in FPPS. About 40% of wt FPPS activity was sufficient to support normal growth of the mutant. With further decline of FPPS activity (20 down to 3%) the amount of ergosterol remained unchanged at ∼0.16% (vs dry weight), whereas growth yield decreased and lag times increased. We postulate that, in addition to ergosterol initiating and maintaining growth of yeast cells, FPP and/or its derivatives participate in these processes.
Strategic, structural contingency and institutional explanations in the adoption of innovative manufacturing practices
Authors: Ketokivi Mikko A , Schroeder Roger G
Published: January 2004

The main argument in this paper is that in order to understand the phenomenon of how innovative manufacturing practices diffuse we need to invoke theoretical arguments other than the ones that are conventionally used. In particular, neo‐institutional arguments can shed light on the determinants of manufacturing practice adoption and implementation. We juxtapose both theoretically and empirically three different theoretical perspectives that can be used to address the phenomenon: strategic contingency, structural contingency and neo‐institutional arguments. A preliminary empirical test of the three competing perspectives is tested in a sample of 164 manufacturing plants. We find that the institutional perspective explains much more of the variance in the practices adopted and implemented by the plants than either the structural contingency or the strategic contingency theories. This motivates future research using some of the less familiar theoretical approaches.
Exploring flexibility and execution competencies of manufacturing firms
Authors: Narasimhan Ram , Talluri Srinivas , Das Ajay
Published: January 2004

Manufacturing flexibilities improve a firm’s ability to react to customer demands without incurring excessive time and cost penalties. While development of manufacturing flexibilities is desirable and indeed critical for some firms, exploiting the flexibility capabilities to achieve tangible firm‐level performance outcomes througheffective executionis becoming increasingly important. This paper presents a conceptual model that introduces two new constructs:flexibility competence and execution competenceas distinct from manufacturing flexibility. Based on the proposed conceptual model and a multistage data envelopment analysis (MDEA) of empirical data, the roles of flexibility and execution competencies in determining performance are examined. The results indicate that some firms are more effective than others in exploiting investments in advanced manufacturing technologies and strategic sourcing initiatives to develop manufacturing flexibilities. Thus, lending credibility to the new construct referred to as flexibility competence. We also conclude that some firms are more effective than others in converting manufacturing flexibilities into tangible firm‐level performance, suggesting that execution competence is an important construct that needs attention. We suggest future research in this area for comprehensively investigating these two new constructs proposed in this paper and identifying the factors that influence them.
Effects of IPO mispricing on the risk and reputational capital of commercial banks
Authors: Fields L.Paige , Fraser Donald R.
Published: January 2004

We provide direct evidence regarding the risk and reputational capital implications of commercial bank securities underwriting activities. Using a large sample of commercial bank underwritten initial public offerings (IPOs) and comparisons with investment bank underwritten issues, we find that (1) commercial banks are no more likely to misprice IPOs than are traditional investment banks, and (2) the market reaction to mispriced IPOs is no greater for commercial banks than for traditional investment banks. Our evidence, thus, is consistent with the policy implications of other research justifying repeal of the Glass–Steagall Act. Specifically, we find no evidence that bank shareholders or the public are exposed to greater risk when banks are allowed to underwriter securities.
Class III alcohol dehydrogenase: consistent pattern complemented with the mushroom enzyme
Authors: Norin Annika , Shafqat Jawed , El-Ahmad Mustafa , Alvelius Gunvor , Cederlund Ella , Hjelmqvist Lars , Jörnvall Hans
Published: January 2004

Mushroom alcohol dehydrogenase (ADH) from Agaricus bisporus (common mushroom, champignon) was purified to apparent homogeneity. One set of ADH isozymes was found, with specificity against formaldehyde/glutathione. It had two highly similar subunits arranged in a three‐member isozyme set of dimers with indistinguishable activity. Determination of the primary structure by a combination of chemical, mass spectrometric and cDNA sequence analyses, correlated with molecular modeling towards human ADHs, showed that the active site residues are of class III ADH type, and that the subunit differences affect other residues. Class I and III forms of ADHs characterized define conserved substrate‐binding residues (three and eight, respectively) useful for recognition of these enzymes in any organism.
A role for expansins in dehydration and rehydration of the resurrection plant Craterostigma plantagineum
Authors: Jones Louise , McQueen-Mason Simon
Published: January 2004

Craterostigma plantagineum is one of the few higher plants capable of surviving desiccation throughout its vegetative tissues. Water loss results in cell shrinkage and a commensurate folding of the cell wall indicating an unusual degree of wall flexibility. We show that wall extensibility undergoes a marked increase during dehydration and rehydration. Similar increases were observed in the activity of expansins in cell walls during these processes suggesting a role for these proteins in increasing wall flexibility. Three α‐expansin cDNAs were cloned from dehydrating leaves and transcript levels for one correlated closely with the observed changes in expansin activity during the dehydration and rehydration of leaves.
The mouse FKBP23 binds to BiP in ER and the binding of C‐terminal domain is interrelated with Ca2+ concentration
Authors: Zhang Xiaobin , Wang Ying , Li Hui , Zhang Wanqi , Wu Di , Mi Huaifeng
Published: January 2004

FK506 binding protein 23 from mouse (mFKBP23) is a peptidyl‐prolyl cis‐trans isomerase (PPIase) from the endoplasmic reticulum (ER), which consists of an N‐terminal PPIase domain and a C‐terminal domain with Ca2+ binding sites. The assay of adsorption from ER extract with glutathione S‐transferase‐mFKBP23 attached to glutathione‐Sepharose 4B shows that mFKBP23 binds to mouse immunoglobulin binding protein (mBiP). The same assay with the recombinant proteins of the N‐ and C‐termini of mFKBP23 shows that the binding of the C‐terminus is Ca2+‐dependent and the switch point is between 2 and 3 mM. By high concentration of Ca2+ this binding cannot be detected. Furthermore, the Ca2+‐regulated binding of mFKBP23 and mBiP in ER can be detected by means of co‐immunoprecipitation.
Coactivator ASC‐2 mediates heat shock factor 1‐mediated transactivation dependent on heat shock
Authors: Hong SunHwa , Kim Sun Hee , Heo Mi Ae , Choi Yoon Ha , Park Min Jung , Yoo Mi Ae , Kim Han Do , Kang Ho Sung , Cheong JaeHun
Published: January 2004

Upon exposure to elevated temperatures, mammalian cells increase the expression of the heat shock proteins (HSP) through activation of the heat shock factor 1 (HSF1). Since most transcription factors require coactivators for efficient transcriptional activity, we tried to identify the coactivator(s) that interacts with and modulates the activities of HSF1. In vitro glutathione S‐transferase (GST) pull‐down assay revealed that HSF1 strongly interacts with activating signal cointegrator (ASC)‐2 and weakly with cyclic adenosine monophosphate responsive element binding protein (CBP). We also show that cotransfection of ASC‐2, but not CBP, potentiates HSF1‐mediated transactivation based on its cognate element (heat shock element, HSE) linked to luciferase reporter. The molecular interaction of HSF1 and ASC‐2 was stimulated by heat shock in cells and the overexpression of HSF1‐interacting domain of ASC‐2 inhibited the specific induced protein association and HSF1‐mediated transactivation. Taking these results together, we suggest that ASC‐2 in a novel coactivator for HSF1 and heat shock stress may contribute the strong active transcription complex through sequential recruitment of HSF1 and ASC‐2.
Did Election Imply the Mistreatment of Non-Israelites?
Authors: Kaminsky Joel S.
Published: January 2004

As a way of working out and consolidating one's religious identity, the
whole-sale slaughter of people (whether in herem,
crusade, or jihad) is exactly what it seems to
be, no more and no less. The pressure that builds up naturally in the idea
of election is here unleashed, and the idea is given its fullest expression.
The Conquest tradition is the primary expression and fulfillment of the
idea—the Urtext. The biblical idea of election is
the ultimate anti-humanistic idea. Jeremy Cott, “The Biblical
Problem of Election,” JES 21 (Spring 1984)
199–228, at 204.Thus did Jeremy Cott, in an article published
nearly two decades ago, starkly pose the dilemma faced by anyone who seeks
to use the Bible as a moral and spiritual guide today. How can one possibly
maintain that the conquest tradition, which relates that God called for the
annihilation of every Canaanite man, woman, and child, is an authoritative
part of Scripture on a par with other items such as the Ten Commandments or
the story of the exodus? The logic behind Cott's statement, at first blush,
seems quite compelling. Its central premise, which almost all contemporary
theologians and biblical scholars would endorse, is that genocide is morally
wrong and could not be a practice decreed by God. Furthermore, the command
to commit genocide appears to conflict with other basic biblical concepts,
innocent along with the guilty.
Discipline and Diet: Feeding the Martyrs in Roman Carthage
Authors: McGowan Andrew
Published: January 2004

Although few Christians were likely to suffer the most violent
consequences of persecution under the Roman Empire, the experiences of those
imprisoned, tortured, or killed were significant far beyond the lives of the
individuals concerned. These living martyrs took on a significance that was
important for the whole of Christian identity, becoming spiritual patrons
dispensing grace, or exemplars of an alternative mode of life.
Jan Blommaert (ed.), Language ideological
debates. (Language, Power and Social Process, 2.) Berlin
& New York: Mouton de Gruyter, 1999. Pp. xiii, 447. Hb $74.00,
pb $25.00.
Authors: Del Pinal Eric Hoenes
Published: January 2004

This volume contributes to the study of language
ideology by focusing on the historical processes through which
ideological positions about the relationship of language and
society are produced and reproduced. Specifically, the contributors
seek to contextualize the ways that language ideologies are
contested in particular, often well publicized debates about
language and its relationships to society. While ostensibly
about linguistic issues, these debates, at one level or another,
also address questions of power and national identity.
David Herman, Story logic. Lincoln &
London: University of Nebraska Press, 2002, Pp. xvi, 477. Hb
$60.00
Authors: De Fina Anna
Published: January 2004

One of the virtues of David Herman's
Story logic lies in its attempt to bring together literary
and linguistic approaches to the study of narrative. The attempt
results in a synthesis that promotes a better understanding
of discourse for literary scholars and a deeper grasp of basic
narratology tools for discourse analysts. The title of the volume
reflects one of the main points of the book: that “stories
both have a logic and are logic in their own right” (p.
22) because they constitute a powerful instrument for understanding
the world. The more general objective of the analyses presented
in the volume is to work toward a cognitive approach to narrative
in which narrative understanding is explained as a process of
creating and updating mental models of particular storyworlds.
Thus, Herman looks at language theory and narrative theory as
theoretical frames that not only can enrich each other, but
that also constitute a resource for cognitive science in general.
Anna Livia, Pronoun envy: Literary uses of
linguistic gender. Oxford & New York: Oxford University
Press, 2001. Pp. x, 237 (including index). Hb $49.95, pb $29.95.
Authors: McConnell-Ginet Sally
Published: January 2004

In 1971, women students at the Harvard Divinity
School began protesting the use in their classes of BOMFOG
(“brotherhood of man, fatherhood of god”) talk,
the equation of the universal with the masculine exemplified
by apparently generic uses of forms like he and
man. Responding to reports of these protests in the
Harvard Crimson, Harvard's linguistics faculty
wrote a letter to the editor explaining that English masculine
forms were linguistically “unmarked” for gender
and patronizingly assuring the protestors that “there
is no need for anxiety or pronoun envy” (quoted in Livia,
p. 3). Once launched, that phrase begged to be a title, and
Anna Livia's enlightening book is a most suitable bearer.
This is a volume from which linguists and others interested
in the linguistic encoding of gender can learn much.
Ron Scollon, Mediated discourse: The nexus of
practice. London & New York: Routledge, 2001. Pp. ix,
182. Pb $29.80; and Yuling Pan, Suzanne Wong Scollon, &
Ron Scollon. Professional communication in international
settings. Malden, MA: Blackwell, 2002. Pp. x, 240. Hb $73.95
Authors: Sun Hao
Published: January 2004

Mediated Discourse (MD)
reports a longitudinal study of the development of a one-year-old
child, focusing on a single, narrowly defined social practice
– handing, or “the simple practice of giving an
object to another person” (p. 12). In this book, R. Scollon
proposes a framework of mediated discourse to address social
(practice) theory, which was “badly in need of an ontogenetic
view of social practice” (vii).

Although Ron Scollon is an author of both books under review, the
second differs from the first, theoretical, work in focusing on practical
application. Professional communication in international settings
(PCIIS) is an excellent book that is much needed by professionals,
researchers, trainers, or anyone else involved in business or professional
communication across cultural boundaries. Different from many other books on
the same subject, its goal is to offer a method for effective communication,
and it can be used as either a textbook or a reference.
Nanette Gottlieb & Ping Chen (eds.), Language
planning and language policy: East Asian perspectives.
Richmond, UK: Curzon, 2001. Pp. x, 210. ISBN 0-7007-1468-5.
Authors: Bruthiaux Paul
Published: January 2004

In this well-focused collection of papers,
editors Gottlieb & Chen present an overview of language
planning and policy issues in East Asia. Given the time-honored
emphasis on scholarship and especially on writing that is
characteristic of the region, it is not surprising to find that
the book is rich in historical information. However, it also
provides a wealth of insights regarding recent developments
across related yet unique settings. In this sense, the volume
fulfills its publicized aim of meeting the needs of students,
researchers, and educated readers with an interest in the complex
language practices of the region.
Julie Lindquist, A place to stand: Politics
and persuasion in a working-class bar. Oxford & New
York: Oxford University Press, 2002. Pp. viii, 199. Pb $29.95.
Authors: Jensen Joli
Published: January 2004

In her preface to A place to stand,
Julie Lindquist writes, “The experience of class in America
is impossible to explain, difficult to render, and dangerous
to address.” In spite of these caveats, she has combined
her experience as a bartender with her graduate training in
theoretical linguistics to render and address, if not to explain,
rhetorical performance among the regulars in a working class-bar
she calls the Smokehouse.
Robert Bringhurst, A story as sharp as a knife:
The classic Haida mythtellers and their world. Vancouver
& Toronto: Douglas & McIntyre, 1999. Pp. 527. Hb $45.00;
Robert Bringhurst, Nine visits to the mythworld: Ghandl of
the Qayahl Llaanas. (Masterworks of the Classical Haida Mythtellers,
vol. 2.) Lincoln: University of Nebraska Press, 2000. Pp. 222. Hb $37.95;
and Robert Bringhurst, Being in being: The collected works of
Skaay of the Qquuna Qiighawaay. (Masterworks of the Classical Haida
Mythtellers, vol. 3.) Lincoln: University of Nebraska Press, 2001. Pp. 397.
Hb. $35.00
Authors: Hymes Dell
Published: January 2004

These three volumes invite a volume in return.
They bring Haida to the fore of what is known of oral narrative
in Native North America. One finds a dedicated philological
sleuth, tracking down original texts and unpublished manuscripts
(see A story as sharp as a knife, pp. 221–2;
Nine visits to the mythworld, p. 17); a historian of
anthropology, reconstructing and relating the story of a young
fieldworker who is now largely forgotten (John R. Swanton);
a pursuit of detail that enters into a past world, identifying
in footnotes and photographs the places and foods and material
culture of that world; and a creative writer reimagining Haida
men, on islands crumbled by disease and occupation, re-creating
in narratives a world their minds could still imagine. Not least,
one finds someone for whom the arts are a normal part of life,
and for whom the conception and misfortunes of a painting by
Velasquez (44–49) can illuminate the relationship between
myth time and historical time in Haida. Finally, the writing
displays an ease, indeed a gift for words, that befits an
established poet, and the books themselves are attractive, as
befits a typographer versed in visual arts. (Bringhurst was
invited to bring out a new edition, Chappell & Bringhurst
1999, of a standard book. The new edition indeed displays two
pages [298–99] in line and verse of Victoria
Howard's “Gitskux and his older brother”
[Clackamas Chinook]; see Hymes 1983. His book of 1992
has been a bestseller.
Paul V. Kroskrity, Rosalie Bethel, & Jennifer
F. Reynolds, Taitaduhaan: Western Mono ways of
speaking. Norman: University of Oklahoma Press, 2002. (CD-ROM)
Authors: Bright William
Published: January 2004

We have become accustomed to seeing reference
works in CD-ROM format, such as the Oxford English
dictionary, often alongside equivalent hardcopy publications.
By contrast, Taitaduhaan (‘Our language’)
is not a reference work, and it is published not merely in that
familiar electronic format but rather as an interactive
CD-ROM, in which the user can move with a finger-click from
written text, to video images, to audio recordings. Is this
a “book,” or an entirely new form of publishing?
In any case, “reading” it is definitely a new
experience for us in these first years of the 21st century.
Community and commodity in French Ontario
Authors: BUDACH GABRIELE , ROY SYLVIE , HELLER MONICA
Published: January 2004

Linguistic minority movements have long adopted
dominant discourses linking language and community. Analysis
of two sites of discursive production in francophone Canada
(literacy centers and a call center workplace in Ontario) shows
that current socioeconomic changes challenge those discourses.
Language and community are uncoupled and redefined as commodities
with exchange value in the globalized market for services and
information. “Community” serves mainly to legitimize
struggles for privileged access to newly commodified linguistic
and cultural resources.
Coffeetalk: Starbucks™ and the commercialization
of casual conversation
Authors: GAUDIO RUDOLF P.
Published: January 2004

This article examines how so-called ordinary
or casual conversational practices in the contemporary United
States are constrained and structured in terms of where, when,
how, and with whom people choose and are able to interact socially.
The focus of analysis is the middle-class sociolinguistic practice
of “coffeetalk” – a term borrowed from U.S.
popular culture to signal the naturalized conflation of
conversation with the commercialized consumption of coffee,
space, and other commodities. The discussion of coffeetalk involves
research methods including critical analyses of the marketing
rhetoric of coffeehouse corporations; informal interviews with
coffeehouse owners, employees and patrons; and the author's
observations as a “native” participant in coffeetalk
and other commodified modes of middle-class social interaction.
By situating coffeetalk within its spatial, temporal and social
contexts, this analysis challenges the claim of some sociolinguists
that conversation is a “naturally occurring” phenomenon
that is ontologically prior to other speech genres. A systematic
investigation of the material and social dimensions of seemingly
ordinary conversational practices demonstrates that these are
inextricably implicated in the political, economic, and
cultural-ideological processes of global capitalism, as symbolized
by the increasingly ubiquitous Starbucks Coffee Company.
American Sign Language in virtual space: Interactions between
deaf users of computer-mediated video communication and the
impact of technology on language practices
Authors: KEATING ELIZABETH , MIRUS GENE
Published: January 2004

According to some discussions concerning new
information technologies and technologically enhanced
communication, we are now in a revolution as profound as the
printing press. The Internet is creating new kinds of meetingplaces
and work areas and the possibilities of new types of relationships
across time and space. This article reports on some ways that
the Internet is shaping language practices in the Deaf community,
with an interest in how new tools mediate and influence human
behavior, including language and the organization of interaction.
This includes the development and manipulation of a
computer-mediated image of self and other, creativity and
problem-solving in new communicative spaces, creating reciprocal
perspectives, new participation frameworks, and specifics of
language change. For the first time, deaf people can communicate
using manual visual language, in many cases their native language,
across space and time zones. This groundbreaking situation makes
the Deaf community a particularly productive site for research
into relationships between technological innovations and new
communicative practices.
Special Issue: New artificial intelligence paradigms for
manufacturing
Authors: GAINES DANIEL M. , REGLI WILLIAM C.
Published: January 2004

This Special Issue was motivated in part by the success
of the 2001 American Association for Artificial Intelligence's
Special Interest Group on Manufacturing (SIGMAN) workshop. SIGMAN
has organized a series of these workshops that highlight significant
advances in academic research and industrial practice. New manufacturing
concepts such as agile/lean manufacturing and virtual manufacturing
place increasing emphasis on the need for more intelligent manufacturing
systems. It is no longer a question of whether artificial intelligence (AI)
technologies will have an impact on manufacturing but one of better
understanding and exploiting the broad potential of AI in this domain.
Asking the right question: Risk and expectation in multiagent
contracting
Authors: BABANOV ALEXANDER , COLLINS JOHN , GINI MARIA
Published: January 2004

In this paper we are interested in the decision problem faced by an
agent when requesting bids for collections of tasks with complex time
constraints and interdependencies. In particular, we study the problem
of specifying an appropriate schedule for the tasks in the request for
bids. We expect bids to require resource commitments, so we expect
different settings of time windows to solicit different bids and
different costs. The agent is interested in soliciting
“desirable” bids, where desirable means bids that can be
feasibly combined in a low-cost combination that covers the entire
collection of tasks. Since the request for bids has to be issued before
the agent can see any bids, in this decision process there is a
probability of loss as well as a probability of gain. This requires the
decision process to deal with the risk posture of the person or
organization on whose behalf the agent is acting. We describe a model
based on Expected Utility Theory and show how an agent can attempt to
maximize its profits while managing its financial risk exposure. We
illustrate the operation and properties of the model and discuss what
assumptions are required for its successful integration in multiagent
contracting applications.
Rapid development of knowledge-based systems via integrated knowledge acquisition
Authors: XING HAO , HUANG SAMUEL H. , SHI J.
Published: January 2004

This paper presents a novel approach, which is based on integrated (automatic/interactive) knowledge acquisition, to rapidly develop knowledge-based systems. Linguistic rules compatible with heuristic expert knowledge are used to construct the knowledge base. A fuzzy inference mechanism is used to query the knowledge base for problem solving. Compared with the traditional interview-based knowledge acquisition, our approach is more flexible and requires a shorter development cycle. The traditional approach requires several rounds of interviews (both structured and unstructured). However, our method involves an optional initial interview, followed by data collection, automatic rule generation, and an optional final interview/rule verification process. The effectiveness of our approach is demonstrated through a benchmark case study and a real-life manufacturing application.
Integrated product and process data for business to business collaboration
Authors: KULVATUNYOU BOONSERM , IVEZIC NENAD , WYSK RICHARD A. , JONES ALBERT
Published: January 2004

Collaborative development of engineered products in a business to business (B2B) environment requires more than the selection of components from an on-line catalogue. It involves the electronic exchange of product, process, and production engineering information during both design and manufacturing. Although the state of the practice does include a variety of ways to exchange product data electronically, it does not extend to the exchange of manufacturing process data. The reason is simple: process data are usually tied to specific manufacturing resources. These resources are not known typically at product development time. This paper proposes an approach called integrated product and process data, in which manufacturing process data are considered during product development. This approach replaces traditional process plans, which are resource specific, with a resource-independent process representation. Such a representation will allow a much wider collaboration among business partners and provide the necessary base for collaborative product development.
Observations of overturning in the upper mesosphere and lower thermosphere
Authors: Larsen M. F. , Liu A. Z. , Gardner C. S. , Kelley M. C. , Collins S. , Friedman J. , Hecht J. H.
Published: January 2004

A number of observations of the sodium density primarily in the mesosphere and lower thermosphere (but also of the electron density structure) have shown what appears to be overturning or convective roll cells near the transition from the mesosphere to the lower thermosphere. The cells are found in the region between 95 and 105 km and occur near the boundary between the region of lower stability in the mesosphere and the region of higher stability in the lower thermosphere. The vertical scale for the rolls is ∼5–6 km, and the timescale is ∼1–3 hours. The rolls occur in a region characterized by large shear in the neutral winds, but the timescales are too long to be explained by simple Kelvin‐Helmholtz instability. We present observations from the University of Illinois lidar facility located at the Starfire Optical Range near Albuquerque, New Mexico, from the Arecibo Observatory in Puerto Rico, and from the Maui/MALT Lidar Facility located on Maui in Hawaii that show the overturning structure. possible mechanisms for generating the convective rolls are discussed, Including the relationship of the observed features to the characteristics expected for an inflection point instability.
Ionospheric assimilation techniques for ARGOS Low‐Resolution Airglow and Aurora Spectrograph (LORAAS) tomographically reconstructed equatorial electron density profiles
Authors: Sojka J. J. , Eccles J. V. , Schunk R. W. , McDonald S. , Thonnard S. , Dymond K. , McCoy R. P.
Published: January 2004

The LORAAS instrument aboard the ARGOS satellite observes line‐of‐sight ultraviolet limb intensities from ionosphere and thermosphere airglow. This study uses tomographically reconstructed electron density profiles (EDPs) from the nightside emissions. The ionospheric reconstruction is performed using a two‐dimensional O+ 1356Å radiative recombination forward model and discrete inverse theory. The forward model assumes a Chapman layer for the vertical electron density distribution from which hmF2, NmF2, and topside scale height are derived for every 90 s limb scan, which is equivalent to 5° resolution in latitude. Since ARGOS is in a near Sun‐synchronous orbit, these EDPs form a latitude slice through the equatorial anomaly structures at approximately 0230 LT. These data reflect ongoing ionospheric processes, and it is necessary to assimilate or compare with a model that contains appropriate ionospheric evolution such as the ionospheric forecast model (IFM). This study addresses the reasonableness of both the reconstructed EDPs and the IFM in describing the equatorial anomalies' diurnal and weather variability. The comparison of the LORASS EDPs with those of IFM for October 2000 show that the EDP reconstruction results compare favorably to the IFM EDPs in peak height and topside scale height. Additionally, the sector‐to‐sector climatology of the observed and modeled equatorial anomalies is similar to within the resolution of the instrument and model. The variability observed in each pass of the satellite is much larger than the IFM variability. The LORASS observation variability indicates that careful assessment of the representation error of the observations should be addressed through supplemental observations.
The fluidization behaviour of ignimbrite at high temperature and with mechanical agitation
Authors: Druitt T. H. , Bruni G. , Lettieri P. , Yates J. G.
Published: January 2004

Experiments were carried out to study the fluidization behaviour of ignimbrite at high temperature and while being mechanically agitated. Geldart group C behaviour occurs up to 565°C when the material is subjected to increasing gas flow (without agitation) from the loosely packed state. In contrast, even gentle mechanical agitation inhibits channelling and results in group‐A type behaviour with homogeneous (non‐bubbling) expansions of up to 30–40%. Bed collapse tests exhibit group‐C behaviour at room temperature, group‐A behaviour at 200–565°C, and transitional behaviour at 55°C. Both elevated temperature and mechanical agitation greatly increase the fluidizability of ignimbrite. It is inferred that a combination of high temperature and shear during transport will promote Geldart group A behaviour in pyroclastic flows.
Hall and Turbulence Effects on Magnetic Reconnection
Authors: Smith D. , Ghosh S. , Dmitruk P. , Matthaeus W. H.
Published: January 2004

We examine the influence of Hall effect and MHD turbulence on the reconnection rate of a large scale periodic sheet pinch in 2.5 dimensional compressible Hall MHD. Simulations indicate that the reconnection rate is enhanced both by increasing Hall parameter and by increasing turbulence amplitude.
Interpretation of recent Antarctic sea ice variability
Authors: Liu Jiping , Curry Judith A. , Martinson Douglas G.
Published: January 2004

Trends in the satellite‐derived Antarctic sea ice concentrations (1979–2002) show pronounced increase (decrease) in the central Pacific sector (Bellingshausen/western Weddell sector) by ∼4–10% per decade. Confidence levels for these regional trends exceed 95%. Positive polarities of the Antarctic Oscillation (AAO) lead to more (less) ice in the eastern Ross/Amundsen sector (Bellingshausen/northern Weddell sector), which are qualitatively opposite to the impacts of positive polarities of the El Niño‐Southern Oscillation (ENSO). The mechanisms responsible for the covariability between the ice and the (a) AAO and (b) ENSO are demonstrated. Over the last 24 years, a positive AAO trend and a slightly negative ENSO trend produce a spatial pattern of ice changes similar to the regional ice trends. However, the magnitude of the ice changes associated with the AAO and ENSO is much smaller than the regional ice trends. More local (or less understood large) scale processes should be investigated for the explanations.
Atmospheric variability of methyl chloride during the last 300 years from an Antarctic ice core and firn air
Authors: Aydin M. , Saltzman E. S. , De Bruyn W. J. , Montzka S. A. , Butler J. H. , Battle M.
Published: January 2004

Measurements of methyl chloride (CH3Cl) in Antarctic polar ice and firn air are used to describe the variability of atmospheric CH3Cl during the past 300 years. Firn air results from South Pole and Siple Dome suggest that the atmospheric abundance of CH3Cl increased by about 10% in the 50 years prior to 1990. Ice core measurements from Siple Dome provide evidence for a cyclic natural variability on the order of 10%, with a period of about 110 years in phase with the 20th century rise inferred from firn air. Thus, the CH3Cl increase measured in firn air may largely be a result of natural processes, which may continue to affect the atmospheric CH3Cl burden during the 21st century.
Tracking a major interplanetary disturbance with SMEI
Authors: Tappin S. J. , Buffington A. , Cooke M. P. , Eyles C. J. , Hick P. P. , Holladay P. E. , Jackson B. V. , Johnston J. C. , Kuchar T. , Mizuno D. , Mozer J. B. , Price S. , Radick R. R. , Simnett G. M. , Sinclair D. , Waltham N. R. , Webb D. F.
Published: January 2004

We present the first clear observations of an Earth‐directed interplanetary disturbance tracked by the Solar Mass Ejection Imager (SMEI). We find that this event can be related to two halo CMEs seen at the Sun about 2 days earlier, and which merged in transit to 1 AU. The disturbance was seen about 16 hours before it reached Earth,and caused a severe geomagnetic storm at the time which would have been predicted had SMEI been operating as a real‐time monitor. It is concluded that SMEI is capable of giving many hours advance warning of the possible arrival of interplanetary disturbances.
A statistical comparison of SuperDARN spectral width boundaries and DMSP particle precipitation boundaries in the nightside ionosphere
Authors: Chisham G. , Freeman M. P. , Sotirelis T.
Published: January 2004

The boundary between quasi‐dipolar (closed) geomagnetic field lines and those connected to the interplanetary magnetic field (open) is a key diagnostic for the magnetospheric system. This study presents an HF radar technique for determining the location of this boundary in the nightside ionosphere and calibrates it with the boundary determined from simultaneous particle precipitation data. The latitudes of spectral width boundaries (SWBs) identified from 5 years (1997–2001) of data from the Halley HF radar of the Super Dual Auroral Radar Network (SuperDARN), in the range 1800–0200 magnetic local time (MLT), have been compared with nightside particle precipitation boundaries (PPBs) identified from measurements from the Defense Meteorological Satellite Program (DMSP) spacecraft. Latitudinal differences were measured between the PPBs and the nearest SWB within a ±10 min UT window and within a ±1 hr MLT window. These differences were then organised into 2‐hour MLT sectors. The statistical distributions of the latitudinal differences show that the nightside SWB correlates best with the b6 PPB, which is a good marker for the open‐closed field line boundary (OCB) in the nightside ionosphere. When considering SWBs determined using different spectral width threshold values, those determined using the lower threshold values (<150 m/s) are offset ∼1–2° equatorward of the b6 boundary suggesting that there is a gradual latitudinal change in spectral width between the b5 and b6 boundaries rather than a step change at the b6 boundary. The results enable the OCB to be determined with confidence in the 1800–0200 MLT sector using SuperDARN radar data.
Equilibrium‐range constant in wind‐generated wave spectra
Authors: Resio Donald T. , Long Charles E. , Vincent C. Linwood
Published: January 2004

The equilibrium range in wind‐driven wave spectra is characterized to have an f−4 form in deep water (k−5/2 shallow‐water form). Absolute energy levels for six physically diverse sites are shown to be well fit by an expression involving the wind speed measured at a fraction of a wavelength above the sea surface in combination with the phase speed of the spectral peak. Observed energy levels suggest that nonlinear wave‐wave interactions are capable of maintaining the observed energy‐flux balance in the equilibrium range.
Global modeling of heterogeneous chemistry on mineral aerosol surfaces: Influence on tropospheric ozone chemistry and comparison to observations
Authors: Bauer S. E. , Balkanski Y. , Schulz M. , Hauglustaine D. A. , Dentener F.
Published: January 2004

Mineral aerosols can affect gas phase chemistry in the troposphere by providing reactive sites for heterogeneous reactions. We present here a global modeling study of the influence of mineral dust on the tropospheric photochemical cycle. This work is part of the Mineral Dust and Tropospheric Chemistry (MINATROC) project, which focussed on measurement campaigns, laboratory experiments, and integrative modeling. The laboratory experiments provide uptake coefficients for chemical species on mineral aerosol surfaces, which are used to compute the heterogeneous reaction rates in the model. The field measurements at Mount Cimone, northern Italy, provide trace gas and aerosol measurements during a Saharan dust episode and are used to evaluate the model. The simulations include the reactions between mineral dust aerosols and the gas‐phase species O3, HNO3, NO3, and N2O5. Under the conditions for the year 2000 the model simulates a decrease in global tropospheric ozone mass by about 5% due to the heterogeneous reactions on dust aerosols. The most important heterogeneous reaction is the uptake of HNO3 on the dust surface, whereby the direct uptake of ozone on dust is not important in atmospheric chemistry. The comparison of the model results to observations indicates that the model simulates well the aerosol mass transported into the Mediterranean during the dust events and the arrival of all major dust events that were observed during a 7 month period. The decrease in ozone concentration during dust events is better simulated by the model when the heterogeneous reactions are included.
Studies of gravity wave–induced fluctuations of the sodium layer using linear and nonlinear models
Authors: Xu Jiyao , Smith A. K.
Published: January 2004

In this paper we develop two models of the response of the sodium layer to gravity waves. The dynamical and photochemical effects are coupled, and ion reactions are included. First, we use a linear model, in which photochemical and dynamical equations are solved simultaneously and the background atmosphere remains fixed. The other model is a time‐dependent, nonlinear, photochemical‐dynamical two‐dimensional model composed of four modules: a dynamical gravity wave model, a middle atmospheric photochemical model, a sodium layer photochemical model, and an ionospheric model. The main differences between the simulations by the two models occur for sodium evolution near the peak and the bottomside of the sodium layer. Simulations indicate that a stable gravity wave induces large perturbations to the atomic sodium distribution at the bottomside of the sodium layer and that the perturbations are in phase with those of temperature. At the topside of the layer, sodium and temperature perturbations are out of phase. The response of the sodium layer to gravity waves is largest around 86 km, in the bottomside of the sodium layer, where the vertical gradients of sodium are larger. The background distribution of sodium evolves in the presence of the wave; the horizontal averaged sodium layer extends to lower altitudes. The sodium layer perturbations persist for a long time after the dynamical gravity wave disappears. For a large amplitude gravity wave the nonlinear simulation of the sodium layer evolution is reasonable, while the linear simulation gives an unphysical solution at the bottom side of the sodium layer.
Holocene Atlantic climate variations deduced from carbonate periplatform sediments (leeward margin, Great Bahama Bank)
Authors: Roth Sven , Reijmer John J. G.
Published: January 2004

A marine sediment core from the leeward margin of Great Bahama Bank (GBB) was subjected to a multiproxy study. The aragonite dominated core MD992201 comprises the past 7230 years in a decadal time resolution and shows sedimentation rates of up to 13.8 m/kyr. Aragonite mass accumulation rates, age differences between planktonic foraminifera and aragonite sediments, and temperature distribution are used to deduce changes in aragonite production rates and paleocurrent strengths. Aragonite precipitation rates on GBB are controlled by exchange of carbonate ions and CO2 loss due to temperature‐salinity conditions and biological activity, and these are dependent on the current strength. Paleocurrent strengths on GBB show high current velocities during the periods 6000–5100 years BP, 3500–2700 years BP, and 1600–700 years BP; lower current speeds existed during the time intervals 5100–3500 years BP, 2700–1600 years BP, and 700–100 years BP. Bahamian surface currents are directly linked to the North Atlantic atmospheric circulation, and thus periods with high (low) current speeds are proposed to be phases of strong (weak) atmospheric circulation.
Catastrophic ice shelf breakup as the source of Heinrich event icebergs
Authors: Hulbe Christina L. , MacAyeal Douglas R. , Denton George H. , Kleman Johan , Lowell Thomas V.
Published: January 2004

Heinrich layers of the glacial North Atlantic record abrupt widespread iceberg rafting of detrital carbonate and other lithic material at the extreme‐cold culminations of Bond climate cycles. Both internal (glaciologic) and external (climate) forcings have been proposed. Here we suggest an explanation for the iceberg release that encompasses external climate forcing on the basis of a new glaciological process recently witnessed along the Antarctic Peninsula: rapid disintegrations of fringing ice shelves induced by climate‐controlled meltwater infilling of surface crevasses. We postulate that peripheral ice shelves, formed along the eastern Canadian seaboard during extreme cold conditions, would be vulnerable to sudden climate‐driven disintegration during any climate amelioration. Ice shelf disintegration then would be the source of Heinrich event icebergs.
Candidate genetic markers and the risk of restenosis after coronary angioplasty
Authors: VÖLZKE Henry , GRIMM Rita , ROBINSON Daniel M. , WOLFF Birger , SCHWAHN Christian , HERTWIG Sabine , MOTZ Wolfgang , RETTIG Rainer
Published: January 2004

The aim of the present study was to test for possible associations between candidate gene polymorphisms and the risk of restenosis and recurrent restenosis after percutaneous transluminal coronary angioplasty (PTCA) without stenting. We followed up 511 PTCA patients, and restenosis and recurrent restenosis were defined according to angiographical criteria. Genotyping of the β-fibrinogen -455 G/A, glycoprotein (GP) IIIa PlA1/PlA2, plasminogen activator inhibitor-1 (PAI-1) 4G/5G, factor V Leiden 1691 G/A, tumour necrosis factor α (TNFα) -238 G/A, TNFα -308 G/A, interleukin (IL)-1α -889 C/T, IL-1β -511 C/T, methylenetetrahydrofolate reductase (MTHFR) 677 C/T and endothelial nitric oxide synthase (eNOS) 4 b/a gene polymorphisms was performed by PCR and restriction-fragment-length-polymorphism-based techniques. One hundred and sixty patients (31.3%) developed restenosis and in 130 of these patients, of whom 123 were available for analysis, a second PTCA without stenting was performed. Of these patients, 35 (28.5%) developed recurrent restenosis. None of the investigated genotypes were associated with the risk of restenosis or recurrent restenosis after PTCA. The degree of stenosis before and immediately after PTCA and the severity of the lesion were independent predictors for restenosis after PTCA. In conclusion, there was no association between the β-fibrinogen -455 G/A, GP IIIa PlA1/A2, PAI-1 4G/5G, factor V Leiden 1691 G/A, TNFα -238 G/A, TNFα -308 G/A, IL-1α -889 C/T, the IL-1β -511 C/T, MTHFR 677 C/T and eNOS 4 b/a gene polymorphisms and the risk of restenosis after PTCA as well as recurrent restenosis after repeated PTCA.
Impaired retrograde transmission of vasodilatory signals via the endothelium in pre-eclampsia: a cause of reduced tissue blood flow?
Authors: ANIM-NYAME N. , SOORANNA S. R. , JOHNSON M. R. , SULLIVAN M. H. , GAMBLE J. , STEER P. J.
Published: January 2004

There is evidence that tissue blood flow is regulated by retrograde transmission of signals initiated at capillary and post-capillary sites, and transmitted via the endothelium to modulate pre-capillary resistance. We have used pre-eclampsia as a model to test the hypothesis that normal endothelium is required to enable adjustment of blood flow to match tissue requirements. Integrity of the endothelial pathway was assessed by measuring calf blood flow at increasing venous pressures, using an established small cumulative-step venous-congestion plethysmography protocol in ten women with pre-eclampsia, 17 normal pregnant controls and ten non-pregnant women. Endothelial cell activation was assessed by measuring plasma levels of the cell adhesion molecules, intercellular cell-adhesion molecule-1 (ICAM-1), vascular cell-adhesion molecule-1 (VCAM-1) and E-selectin. Baseline calf blood flow was significantly lower in pre-eclampsia than in the other two groups (P<0.0001; ANOVA). In the pre-eclampsia group, there was a fall in blood flow as venous congestion pressure was raised (P<0.0001; ANOVA). No such change was observed in the other two groups. A significant inverse correlation was observed between the reduction in blood flow in pre-eclampsia and the levels of E-selectin (r=-0.92, P=0.0002), VCAM-1 (r=-0.93, P=0.0008) and ICAM-1 (r=-0.86, P=0.001). The differences between the pre-eclamptic women and the other two groups support the notion that the failure to sustain blood flow during a cumulative pressure step protocol in the pre-eclamptic group might be influenced by interference with the retrograde transmission of signals via the endothelium in these patients.