bluuebunny/crossref_metadata_2025 huggingface dataset:
Theory of Turbulent Eddies
Authors: Kirwan A. D.
Published: December 2004

It is postulated that the turbulent velocity can be expressed as the product of a mean eddy rate of strain and a turbulent displacement vector. Conservation equations for the turbulent displacement variance are derived along with nine turbulent moment of momentum equations which determine the eddy rate of strain. The Reynolds flux of a scalar is also investigated. A geometric interpretation of the Reynolds stress and turbulent kinetic energy in terms of the displacement vector is obtained.
Experimental Investigation of Separated Boundary Layer Undergoing Transition to Turbulence
Authors: Gerrard J. H.
Published: December 2004

Experiments have been performed in the wakes of circular cylinders. It is found that the mean thickness of the separated layer does not change significantly between Reynolds numbers, based on cylinder diameter, 5000 and 20 000. In the layer the velocity pulsates and the position of the layer oscillates at the vortex shedding frequency and also at a less clearly defined frequency an order of magnitude lower. The instantaneous thickness was determined, using two hot-wire anemometers, by observation of the transition waves which accompany transition to turbulence in the layer. It was found that this instantaneous thickness increased by a factor of 1.8 between Reynolds numbers 5000 and 20 000. These experiments corroborate the previously published theory of the determination of the frequency of vortex shedding from bluff bodies.
The wave equation on the Schwarzschild metric II. Local decay for the spin-2 Regge–Wheeler equation
Authors: Blue P. , Soffer A.
Published: December 2004

Odd-type spin-2 perturbations of Einstein’s equation can be reduced to the scalar Regge–Wheeler equation. We show that the weighted norms of solutions are in L2 of time and space. This result uses commutator methods and applies uniformly to all relevant spherical harmonics.
Complete genome sequencing of
Anaplasma marginale
reveals that the surface is skewed to two superfamilies of outer membrane proteins
Authors: Brayton Kelly A. , Kappmeyer Lowell S. , Herndon David R. , Dark Michael J. , Tibbals David L. , Palmer Guy H. , McGuire Travis C. , Knowles Donald P.
Published: December 2004

The rickettsia
Anaplasma marginale
is the most prevalent tick-borne livestock pathogen worldwide and is a severe constraint to animal health.
A. marginale
establishes lifelong persistence in infected ruminants and these animals serve as a reservoir for ticks to acquire and transmit the pathogen. Within the mammalian host,
A. marginale
generates antigenic variants by changing a surface coat composed of numerous proteins. By sequencing and annotating the complete 1,197,687-bp genome of the St. Maries strain of
A. marginale
, we show that this surface coat is dominated by two families containing immunodominant proteins: the
msp
2 superfamily and the
msp
1 superfamily. Of the 949 annotated coding sequences, just 62 are predicted to be outer membrane proteins, and of these, 49 belong to one of these two superfamilies. The genome contains unusual functional pseudogenes that belong to the
msp
2 superfamily and play an integral role in surface coat antigenic variation, and are thus distinctly different from pseudogenes described as byproducts of reductive evolution in other
Rickettsiales
.
SNP detection using peptide nucleic acid probes and conjugated polymers: Applications in neurodegenerative disease identification
Authors: Gaylord Brent S. , Massie Michelle R. , Feinstein Stuart C. , Bazan Guillermo C.
Published: December 2004

A strategy employing a combination of peptide nucleic acid (PNA) probes, an optically amplifying conjugated polymer (CP), and S1 nuclease enzyme is capable of detecting SNPs in a simple, rapid, and sensitive manner. The recognition is accomplished by sequence-specific hybridization between the uncharged, fluorescein-labeled PNA probe and the DNA sequence of interest. After subsequent treatment with S1 nuclease, the cationic water soluble CP electrostatically associates with the remaining anionic PNA/DNA complex, leading to sensitized emission of the labeled PNA probe via FRET from the CP. The generation of fluorescent signal is controlled by strand-specific electrostatic interactions and is governed by the complementarity of the probe/target pair. To assess the method, we compared the ability of the sensor system to detect normal, wild-type human DNA sequences, and those sequences containing a single base mutation. Specifically, we examined a PNA probe complementary to a region of the gene encoding the microtubule associated protein tau. The probe sequence covers a known point mutation implicated in a dominant neurodegenerative dementia known as frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17), which has clinical and molecular similarities to Alzheimer's disease. By using an appropriate PNA probe, the conjugated polymer poly[(9,9-bis(6′-
N
,
N
,
N
-trimethylammoniumhexylbromide)fluorene)-co-phenylene] and S1 nuclease, unambiguous FRET signaling is achieved for the wild-type DNA and not the mutant sequence harboring the SNP. Distance relationships in the CP/PNA assay are also discussed to highlight constraints and demonstrate improvements within the system.
Identification of a nematode chemosensory gene family
Authors: Chen Nansheng , Pai Shraddha , Zhao Zhongying , Mah Allan , Newbury Rebecca , Johnsen Robert C. , Altun Zeynep , Moerman Donald G. , Baillie David L. , Stein Lincoln D.
Published: December 2004

Taking advantage of the recent availability of the whole genome sequence of
Caenorhabditis briggsae
, a closely related nematode to
Caenorhabditis elegans
, we have examined the chemosensory gene superfamily by using comparative genomic methods. We have identified a chemosensory gene family, serpentine receptor class ab (
srab
), which exists in both species with 25 members in
C. elegans
and 14 members in
C. briggsae
. More than 20% of these gene models are reannotated. The
srab
family is similar to, but distinct from, the previously described serpentine receptor class a (
sra
) family and shows a differential expansion in
C. elegans
similar to that previously described for
sra
. The cellular expression patterns for multiple members of the
srab
family in both phasmid neurons in the tail and amphid neurons in the head supports the conclusion that they are chemosensory genes and suggests that they may play a role in integrating chemosensory inputs from both ends of the organism. The expansion of both the
srab
and
sra
gene families in
C. elegans
relative to
C. briggsae
is due to multiple rounds of tandem duplication and translocation of individual genes.
Bone morphogenetic protein (BMP) signaling controls hair pigmentation by means of cross-talk with the melanocortin receptor-1 pathway
Authors: Sharov Andrey A. , Fessing Michael , Atoyan Ruzanna , Sharova Tatyana Y. , Haskell-Luevano Carrie , Weiner Lorin , Funa Keiko , Brissette Janice L. , Gilchrest Barbara A. , Botchkarev Vladimir A.
Published: December 2004

Hair pigmentation is controlled by tightly coordinated programs of melanin synthesis and involves signaling through the melanocortin type 1 receptor (MC-1R) that regulates the switch between pheomelanogenesis and eumelanogenesis. However, the involvement of other signaling systems, including the bone morphogenetic protein (BMP) pathway, in the control of hair pigmentation remains to be elucidated. To assess the effects of BMP signaling on hair pigmentation, transgenic mice overexpressing the BMP antagonist noggin (promoter: keratin 5) were generated. Whereas wild-type C3H/HeJ mice have a subapical yellow band on otherwise black dorsal hairs, K5-Noggin mice are characterized by the absence of a yellow band and near-black pigment in dorsal coat. Noggin overexpression is accompanied by strongly reduced levels of Agouti signal protein and enhanced expression of microphthalmia transcription factor in the midphase of the hair-growth cycle. Wild-type color in K5-Noggin mice is restored by administration of a synthetic MC-1R antagonist resulting in the reappearance of a subapical yellow band. BMP-4 stimulates the expression of Agouti transcripts and protein in primary epidermal keratinocytes, and BMP signaling positively regulates dermal papilla-specific enhancer of the
Agouti
gene in primary dermal fibroblasts. Taken together, these data suggests that BMP signaling controls the expression of Agouti protein in the hair follicle and provide evidence for interaction between BMP and MC-1R signaling pathways to modulate the balance between pheomelanogenesis and eumelanogenesis during hair growth.
Propagation of an infertile hermaphrodite mouse lacking germ cells by using nuclear transfer and embryonic stem cell technology
Authors: Wakayama Sayaka , Kishigami Satoshi , Van Thuan Nguyen , Ohta Hiroshi , Hikichi Takafusa , Mizutani Eiji , Yanagimachi Ryuzo , Wakayama Teruhiko
Published: December 2004

Animals generated by systematic mutagenesis and routine breeding are often infertile because they lack germ cells, and maintenance of such lines of animals has been impossible. We found a hermaphrodite infertile mouse in our colony, a genetic male with an abnormal Y chromosome lacking developing germ cells. We tried to clone this mouse by conventional nuclear transfer but without success. ES cells produced from blastocysts, which had been cloned by using somatic cell nuclear transfer (ntES cells) from this mouse, were also unable to produce offspring when injected into enucleated oocytes. Although we were able to produce two chimeric offspring using these ntES cells by tetraploid complementation, they were infertile, because they also lacked developing germ cells. However, when such ntES cells were injected into normal diploid blastocysts, many chimeric offspring were produced. One such male offspring transmitted hermaphrodite mouse genes to fertile daughters via X chromosome-bearing sperm. Thus, ntES cells were used to propagate offspring from infertile mice lacking germ cells.
Systematic Analysis of the Relation of Electron Transport and ATP Synthesis to the Photodamage and Repair of Photosystem II in Synechocystis
Authors: Allakhverdiev Suleyman I. , Nishiyama Yoshitaka , Takahashi Shunichi , Miyairi Sachio , Suzuki Iwane , Murata Norio
Published: December 2004

The photosynthetic machinery and, in particular, the photosystem II (PSII) complex are susceptible to strong light, and the effects of strong light are referred to as photodamage or photoinhibition. In living organisms, photodamaged PSII is rapidly repaired and, as a result, the extent of photoinhibition represents a balance between rates of photodamage and the repair of PSII. In this study, we examined the roles of electron transport and ATP synthesis in these two processes by monitoring them separately and systematically in the cyanobacterium Synechocystis sp. PCC 6803. We found that the rate of photodamage, which was proportional to light intensity, was unaffected by inhibition of the electron transport in PSII, by acceleration of electron transport in PSI, and by inhibition of ATP synthesis. By contrast, the rate of repair was reduced upon inhibition of the synthesis of ATP either via PSI or PSII. Northern blotting and radiolabeling analysis with [35S]Met revealed that synthesis of the D1 protein was enhanced by the synthesis of ATP. Our observations suggest that ATP synthesis might regulate the repair of PSII, in particular, at the level of translation of the psbA genes for the precursor to the D1 protein, whereas neither electron transport nor the synthesis of ATP affects the extent of photodamage.
The Universe
Authors: Simons Peter
Published: December 2004

It is often said by philosophers that the term ‘the universe’ is illegitimate, whether because the notion of ‘all things’ is incoherent, or inconsistent, or cannot even be meaningfully expressed. The reasons may be drawn from metaphysics, or logic, or the philosophy of language, or the philosophy of mathematics. In this essay I argue that the term is legitimate, withstanding all criticisms, and that there is a single best meaning for it, which is that it is a semantically plural term standing equally for every existing object.

‘Forty‐two’, said Deep Thought, with infinite majesty and calm.

(Douglas Adams, The Hitch‐Hiker's Guide to the Galaxy)
Shareability and Objectivity
Authors: Sullivan Arthur
Published: December 2004

The aim of this essay is to work toward a better understanding of the metaphysical status of meaning by critically examining two arguments – one is Plato’s, the second Frege's – along the following lines:

P1: Meaning is shared in successful communication.

P2: Successful communication occurs.

 C: Therefore, meaning is objective.

The first two sections are dedicated to expounding and justifying the two premises; the third distinguishes some relevant notions of objectivity. Sections four and five discuss the arguments of Plato and Frege, with a view to paring away some potentially misleading ways of speaking, and avoiding any slippage among distinct senses of ‘objective’. The sixth section analyses the content of the claim that abstract objects exist. I conclude by criticizing some assumptions, and drawing some morals, about the place of meaning in one's metaphysical world‐view.
Sense and Simplicity: Wittgenstein's Argument for Simple Objects
Authors: Tejedor Chon
Published: December 2004

This paper puts forward an alternative interpretation of the argument for simple objects advanced in the 2.0s of the Tractatus. In my view, Wittgenstein derives the simplicity of objects directly from his account of possible states, complex objects and senseful propositions. The key to Wittgenstein's argument is the idea that, if there were no simple objects, possible states would not be necessarily possible. If this were the case, however, there would be no senseful language, in Wittgenstein's view. One of the subsidiary aims of this paper is to question the idea that Wittgenstein posits simples because, without them, language would be infinitely analysable.1
Can Jesus Scholarship Escape from Racism?
Authors: Moyise Steve
Published: December 2004

Book reviewed in this article:

Shawn Kelly, Racializing Jesus: Race, Ideology and the Formation of Modern Biblical Scholarship
Unemployment May Be Lower if Unions Bargain over Wages and Employment
Authors: Egger Hartmut
Published: December 2004

This paper addresses the question under which circumstances unemployment can be lower if unions bargain over wages and employment in a general equilibrium framework. Thereby, it turns out that the unemployment rate may negatively depend on the wage rate, if the unemployment compensation scheme contains a constant real term in addition to the replacement ratio component. This is, compared with a pure replacement ratio scheme, the more plausible formalization of the real world’s compensation systems, at least for European countries. Besides the theoretical analysis, the paper also derives political implications by identifying the relevant parameters for the decision on whether weakening unions will be a good strategy for an economy to overcome its unemployment problem.
European Capital Flows and Regional Risk
Authors: Bayoumi Tamim , Sarno Lucio , Taylor Mark P.
Published: December 2004

We look at a range of issues concerning capital flows in Europe. We gauge the extent of European capital mobility through an examination of saving–investment correlations. Moreover, we provide further evidence on the extent and effect of European capital mobility through an examination of GNP/GDP ratios across the largest European countries and a comparison of these with similar calculations executed for regions within the UK. Finally, we examine the role of private financial markets in reducing regional risk by developing an empirical model which is then estimated on data for the European Union.
Growth and stability in a model with Pasinettian saving behaviour and neoclassical technology
Authors: Faria João Ricardo , Teixeira Joanílio Rodolpho
Published: December 2004

We analyse a Kaldor–Pasinetti two‐class model of growth and distribution in which fiscal activity is explicitly introduced along the lines of Pasinetti (‘Ricardian Debt/Taxation Equivalence in the Kaldor Theory of Profits and Income Distribution’, Cambridge Journal of Economics, Vol. 13 (1989), pp. 25–36). Following the approach of Darity (‘A Simple Analytics of Neo‐Ricardian Growth and Distribution’, American Economic Review, Vol. 71 (1981), pp. 978–993) the model is reduced to a dynamic system where the Cambridge equation is one of the possible steady‐state solutions. The conditions for its local stability are studied and a numerical example is presented. The anti‐dual case is more likely to occur in order to guarantee the local stability of the Cambridge equation.
Merton's portfolio optimization problem in a Black and Scholes market with non‐Gaussian stochastic volatility of Ornstein‐Uhlenbeck type
Authors: Benth Fred Espen , Karlsen Kenneth Hvistendahl , Reikvam Kristin
Published: December 2004

We study Merton's classical portfolio optimization problem for an investor who can trade in a risk‐free bond and a stock. The goal of the investor is to allocate money so that her expected utility from terminal wealth is maximized. The special feature of the problem studied in this paper is the inclusion of stochastic volatility in the dynamics of the risky asset. The model we use is driven by a superposition of non‐Gaussian Ornstein‐Uhlenbeck processes and it was recently proposed and intensively investigated for real market data by Barndorff‐Nielsen and Shephard (2001). Using the dynamic programming method, explicit trading strategies and expressions for the value function via Feynman‐Kac formulas are derived and verified for power utilities. Some numerical examples are also presented.
An optimal Strategy for Hedging with Short‐Term Futures Contracts
Authors: Larcher G. , Leobacher G.
Published: December 2004

The search for an optimal strategy to reduce the running risk in hedging a long‐term supply commitment with short‐dated futures contracts leads to a class of intrinsic optimization problems. We give an explicit analytic solution for this optimization problem if the market price of the commodity is based on a simple Gaussian model, thereby replacing previously used incomplete approximations to the optimal strategy.
Non‐Sentential Assertions and the Dependence Thesis of Word Meaning
Authors: Kenyon Tim
Published: December 2004

To assert is to utter a sentence under certain conventions, claims Michael Dummett. This view runs afoul of empirical evidence indicating the widespread assertoric use of non‐elliptical words and phrases. Dummett also advances two theses apparently related to his sentence conventionalism: that word meaning depends on sentence meaning, and that language is (in some sense) prior to thought. I argue that these latter two theses are independent of the empirically dubious Sentential Thesis. Plausibly, the wider Dummettian logico‐metaphysical programme is not impugned by the existence of non‐sentential assertions.
‘Zealotry or Nostalgic Regret’?1 Women Leaders in Technical and Further Education in Australia: Agents of Change, Entrepreneurial Educators or Corporate Citizens?
Authors: Blackmore Jill , Sachs Judyth
Published: December 2004

Education has been restructured in many Western post‐industrial nation states during the 1990s. The Australian Technical and Further Education sector (TAFE) has been particularly susceptible to discourses of responsiveness to the market and the new entrepreneuralism. This article explores how women have been repositioned in contradictory and ambiguous ways as the new entrepreneurial middle managers by existing and emergent discourses that circulated in and through TAFE organizations. In turn, it points to how discourses of change management and client responsiveness took on particular readings within specific institutional and professional cultures of the eight Technical and Further Education institutions (TAFEs). At the same time, the restructuring that arose from the corporatization of TAFE, in a highly gendered process, through the twin strategies of marketization and the new managerialism produced new possibilities for individual women educators who moved up into middle management. Yet these individual women were positioned within highly masculinist ‘neo‐corporate bureaucratic cultures’ that co‐opted their passion for the capacity of education to make a difference and incorporated these new entrepeneurial work identities.
The Income Splitting Method: Is it Good for Both Marriage Partners?
Authors: Wrede Matthias
Published: December 2004

This paper analyzes how deviating from individual taxation affects married couples. The focus is on time allocation, on investment in family-specific human capital and on distribution of income within the family. Two insights are discussed in detail. First, the distribution of tax-reduction gains due to the income splitting system depends on whether the family has been started or not. After marriage, joint taxation increases redistribution among family members. Second, although joint taxation reduces the tax burden of the family, it might harm the marriage partner that is more productive in household production provided that potential marriage partners foresee the effects of joint filing on the time allocation within the family.
The U.S. Federal Executive in an Era of Change
Authors: Aberbach Joel D.
Published: December 2004

This article examines changes in the background characteristics, attitudes, and behavior patterns of high‐level U.S. federal executives. It also considers the impact of the New Public Management (NPM) movement. The data indicate that despite intense struggles about the role of the public sector, top civil servants remain a well‐educated, experienced, and highly motivated group, the members of which compare favorably to top executives in the private sector. The data also suggest that the Civil Service Reform Act (CSRA) of 1978 has been effective in producing a more politically responsive corps of career civil servants, and that administrators (both career and noncareer) are increasingly attuned to the more technical and legal aspects of their roles and less oriented to protecting particular interests or clientele groups. NPM‐style changes are still in progress and remain controversial, but it appears that political leaders continue to have an excellent (and increasingly diverse) group of career people to work with and a system that—at least in part due to the CSRA reforms—is more responsive to them than before. The top part of the U.S. bureaucracy may have been bent and reshaped in many ways over the last thirty years, but, despite widely publicized fears, it has not broken.
The antiquity of the nation? Critical reflections from the ancient Near East
Authors: Routledge Bruce
Published: December 2004

Debates over the antiquity/modernity of the nation have often made use of evidence from the ancient Near East. In doing so, these debates employ the distant past principally as a ‘mirror’ of the present, using contrast or similitude to argue for a particular understanding of nations and nationalism since the eighteenth century. In this manner, both ‘Modernist’ and ‘Perennialist’ approaches incorporate pre‐modern contexts into the categories and priorities of modernity. This article critically reviews several influential studies on nations and nationalism in light of ancient Near Eastern evidence in order to highlight the narrowing of possibilities that this practice involves. I argue that the cost of this narrowing is not so much a misunderstood past as a mystified present.
The last refuge of a scoundrel: patriotism, militarism and the Russian national idea*
Authors: Sperling Valerie
Published: December 2004

In a nation‐state, where ethnic and territorial borders coincide, patriotism may easily have an exclusivist‐nationalist component, and be used to serve the goals of politicians hoping to mobilise the population for destructive goals. In a multinational state like Russia, the militaristic patriotism that Yeltsin's and Putin's administrations promote can also carry that risk. The Russian state leadership's use of a militaristic patriotism as a means to generate popular support risks unleashing ethnic chauvinism and the military domination of civilian institutions. Such phenomena cast doubt on the prospects for Russia's state‐building process to proceed along liberal democratic lines. Non‐governmental organisations, such as Russia'sCommittee of Soldiers' Mothers, however, have devised an alternative vision of patriotism, relying on rule of law and the observance of civil rights, and thereby hold out a slim hope for reframing Russian patriotism and building a peaceful democracy.
Source memory for the color of pictures: Event‐related brain potentials (ERPs) reveal sensory‐specific retrieval‐related activity
Authors: Cycowicz Yael M. , Friedman David
Published: December 2004

Remembering the context (i.e., source) in which an event occurred reveals episodic memory effects (EM) in the event‐related brain potentials (ERP). In some verbal source memory experiments, a late prefrontal EM effect has been observed. In a different, pictorial source memory paradigm, a late, parieto‐occipital EM effect was recorded. To assess whether these two EM effects stemmed from differences in task paradigms or from source‐attribute differences, ERPs were recorded during source memory retrieval for object colors in two tasks. In the sequential task, old/new judgments were followed by source judgments (i.e., color). In the exclusion task, source memory judgments coincided with recognition judgments. For both tasks, late, parietao‐occipital EM effects were observed. These findings suggest that it is not the nature of the task, but rather the perceptual characteristics of the source that lead to the presence of the parieto‐occipital EM effect. The data further imply that memories for perceptual attributes such as color are stored in and retrieved from sensory‐specific cortical areas.
The effect of stimulus modality and task difficulty on attentional modulation of blink startle
Authors: Neumann David L. , Lipp Ottmar V. , McHugh Meredith J.
Published: December 2004

The effects of the sensory modality of the lead stimulus and of task difficulty on attentional modulation of the electrical and acoustic blink reflex were examined. Participants performed a discrimination and counting task with either two acoustic, two visual, or two tactile lead stimuli. In Experiment 1, facilitation of the electrically elicited blink was greater during task‐relevant than during task‐irrelevant lead stimuli. Increasing task difficulty enhanced magnitude facilitation for acoustic lead stimuli. In Experiment 2, acoustic blink facilitation was greater during task‐relevant lead stimuli, but was unaffected by task difficulty. Experiment 3 showed that a further increase in task difficulty did not affect acoustic blink facilitation during visual lead stimuli. The observation that blink reflexes are facilitated by attention in the present task domain is consistent across a range of stimulus modality and task difficulty conditions.
ERP differences in visual attention processing between attention‐deficit hyperactivity disorder and control boys in the absence of performance differences
Authors: Karayanidis Frini , Robaey Philippe , Bourassa Michelle , de Koning David , Geoffroy Guy , Pelletier Gilles
Published: December 2004

Event‐related potentials (ERPs) were recorded during a visual two‐choice reaction time (RT) task in attention‐deficit hyperactivity disorder (ADHD) and control boys selected using strict inclusion and exclusion criteria. No group differences were found in mean RT and correct responses. Although early occipital ERPs were not affected in the ADHD group, the peak latency of early anterior ERPs (N1, P1, N2) was significantly delayed. ADHD showed a larger effect of stimulus type on the frontal negativity (N530) and the posterior late negativity (nSW) and a smaller effect of stimulus type on anterior N2 and posterior P3b amplitude. The development of N530 and P450 amplitude across blocks of five trials was analyzed using orthogonal polynomial trend analysis of variance software. In the control group, P450 amplitude to “frequent” stimuli reduced across blocks. In the ADHD group, N530 amplitude increased for “rare” stimuli across blocks. It is suggested that the ADHD group showed a lack of automatization of the categorization process with increasing time on task for which they compensated by controlled attentional processes.
α2‐Noradrenergic effects on ERP and behavioral indices of auditory information processing
Authors: Turetsky Bruce I. , Fein George
Published: December 2004

Norepinephrine is believed to modulate CNS processing of environmental signals. However, its specific role in stimulus evaluation processes has not been delineated. We examined the effects of the α2 noradrenergic agents, clonidine and yohimbine, on ERP and performance measures of auditory information processing. Ten healthy participants performed a three‐tone target detection experiment, receiving either placebo, 0.2 mg clonidine, or 30 mg yohimbine, in a double‐blind randomized design. The principal locus of action of the noradrenergic agents occurred between 100 and 200 ms poststimulus. P200 latency was sped by yohimbine and slowed by clonidine, and the frontal P3a was shifted in tandem. Components related to target detection (N250 and P3b) were unaffected. The results suggest that norepinephrine modulates CNS mechanisms of selective attention to infrequent stimuli. This may be relevant for patients with schizophrenia, a subset of whom exhibit selective abnormalities of these same ERP components. Our results offer a possible link between these two sets of findings, suggesting that some patients with schizophrenia may have dysfunctional noradrenergic systems.
The studia humanitatis and the making of a humanist career: Marcantonio Sabellico's exploitation of humanist literary genres
Authors: Chavasse Ruth
Published: December 2004

Sabellico is known as the historian of Renaissance Venice, but there is much more to be understood about this ambitious humanist and his success in establishing a secure career for himself in his adopted city. This paper explores the ways in which Sabellico in the closing years of the Quattrocento took advantage of the established studia humanitatis to master a variety of its genres and disciplines. Sabellico was also a master of publicity through the new medium of the printing press, and the reader can be guided through his published works and work in progress in two important letters written in 1493 and intended for publication. The paper considers first the relation between his works and his appointments and civic duties in public employment in Udine and Vicenza, on to his twenty years in government service in Venice. Secondly it surveys the various genres that he explored, and shows how his works complied with contemporary expectations from the studia humanitatis. At the same time, the discussion reveals his own understanding of this cultural and intellectual programme. (pp. 27–38)
A contradiction in terms: Skelton's ‘effecte energiall’ in A Replycacion
Authors: Griffiths Jane
Published: December 2004

This paper tests the commonplace that John Skelton's late poem A Replycacion (1527– 8) contains the first English formulation of the Platonic theory of divine inspiration. It argues first that Skelton's use of the term ‘effecte energiall’ suggests the influence of Aristotle as well as of Plato, second that Skelton's ‘divine inspiration’ can be read as a metaphor for the activity of the poet's own mind. In asserting the poet's originary power at a time when his authority was still widely thought to be derivative, the poem thus anticipates late sixteenth‐century views of poetic authority. (pp. 55–68)
Georg Fabricius and inscriptions as a source of law
Authors: Stenhouse William
Published: December 2004

In 1549 the German Protestant Georg Fabricius (1516–71) edited the first short selection of Roman inscriptions specifically to focus on legal texts. This was a key moment in the history of classical epigraphy: for the first time in print a humanist explicitly demonstrated the value of such archaeological remains for the discipline of law, and implicitly accorded texts written on stone the same status of those recorded in manuscripts. This article situates Fabricius’ work within the antiquarian scholarship of his time. (pp. 96–107)
Problem Definitions and Policy Contradictions: John F. Kennedy and the “Space Race”
Authors: Kay W. D.
Published: December 2004

Usually, when governments appear to be pursuing contradictory or mutually exclusive goals, the response of the scholarly community has been to look for evidence of bureaucratic error, a lack of leadership, or some other type of administrative malfunction. This essay argues that the concept of problem (or issue) definition, which has been widely applied in the study of public policy, may in some cases also help explain the occurrence of this phenomenon as well. Using as an example a major (and, at the time, quite startling) policy “reversal” in President Kennedy's approach to the U.S. space program, the essay shows how the appearance of a “contradiction” within the administration may well have been the result of a disagreement over how U.S. space policy was to be defined.
The real‐time polymerase chain reaction‐guided modulation of immunosuppression enables the pre‐emptive management of Epstein–Barr virus reactivation after allogeneic haematopoietic stem cell transplantation
Authors: Cesaro Simone , Murrone Antonio , Mengoli Carlo , Pillon Marta , Biasolo Maria A. , Calore Elisabetta , Tridello Gloria , Varotto Stefania , Alaggio Rita , Zanesco Luigi , Palù Giorgio , Messina Chiara
Published: December 2004

To assess a real‐time polymerase chain reaction‐based modulation of immunosuppression in patients with an increasing Epstein–Barr virus (EBV) viral load, we studied 79 paediatric allogeneic stem cell transplantations (allo‐SCT) performed between January 1998 and December 2003. EBV reactivation was observed in 42 of 79 patients (53%) after a median time of 45 d from allo‐SCT: 37 (88%) and five (12%) patients had received the graft from an unrelated and a related donor respectively (P = 0·001). Twenty‐eight patients (67%) had a viral load ≥300 genomic copies ×105 peripheral blood mononuclear cells (PBMC) and antithymocyte globulin was the only factor significantly associated with EBV reactivation (P = 0·001, RR 7·1). Among these 28 patients, immunosuppression was suspended and reduced in 17 and 11 patients respectively. Overall, post‐transplant lymphoproliferative disease was diagnosed in one of 79 patients (1%). The pre‐emptive modulation of immunosuppression in patients with EBV reactivation and a viral load ≥300 genomic copies ×105 PBMC did not negatively influence transplant‐related mortality, overall survival or event‐free survival. In conclusion, EBV reactivation is frequent even in ‘low risk’ patients and the pre‐emptive modulation of immunosuppression enables it to be managed safely, with no significant flare in graft‐versus‐host disease status.
Darbepoetin alpha for the treatment of anaemia in low‐intermediate risk myelodysplastic syndromes
Authors: Musto Pellegrino , Lanza Francesco , Balleari Enrico , Grossi Alberto , Falcone Antonietta , Sanpaolo Grazia , Bodenizza Carlo , Scalzulli Potito Rosario , Sala Antonio La , Campioni Diana , Ghio Riccardo , Cascavilla Nicola , Carella Angelo Michele
Published: December 2004

Thirty‐seven anaemic subjects with low‐to‐intermediate risk myelodysplastic syndrome (MDS) received the highly glycosylated, long‐acting erythropoiesis‐stimulating molecule darbepoetin‐alpha (DPO) at the single, weekly dose of 150 μg s.c. for at least 12 weeks. Fifteen patients (40·5%) achieved an erythroid response (13 major and two minor improvements, respectively, according to International Working Group criteria). Such results are currently maintained after 7–22 months in 13 of the responders, one of whom required iron substitutive therapy during the treatment. One patient relapsed after 4 months. Another responder died after 5 months because of causes unrelated to the treatment. No relevant side‐effects were recorded. At multivariate analysis, significant predictive factors of response were baseline serum levels of endogenous erythropoietin <100 IU/l, absent or limited transfusional needs, no excess of blasts and hypoplastic bone marrow. This study suggests that DPO, at the dose and schedule used, can be safely given in low‐intermediate risk MDS and may be effective in a significant proportion of these patients.
R255h Amino acid substitution of protein Z identified in patients with factor V Leiden mutation
Authors: Kemkes‐Matthes Bettina , Matthes Karl J. , Souri Masayoshi , Koseki‐Kuno Shiori , Ichinose Akitada
Published: December 2004

The clinical significance of diminished protein Z in plasma is controversial. Studies in mice demonstrated that deficiency of protein Z dramatically increases the prothrombotic tendency of factor V Leiden mutation. This finding was confirmed by initial results in humans, indicating that thromboembolism in factor V Leiden patients with lowered protein Z level occurs earlier than in patients with normal protein Z levels. Consequently, the aim of our present study was to find out whether genetic alterations of protein Z were demonstrated in patients with factor V Leiden mutation and early onset of thromboembolic disease. DNA‐sequencing of the protein Z gene was performed in two patients with factor V Leiden mutation, early onset of thromboembolism, and lowered protein Z levels. In both patients, R255H substitution of the protein Z gene was identified. Subsequently, the R255H substitution was also found in 12 of 132 additional patients. Patients presenting with the R255H substitution in addition to factor V Leiden mutation showed thromboembolic events more frequently than factor V Leiden patients without R255H substitution of the protein Z gene. In conclusion, R255H substitution of the protein Z gene seems to influence clinical symptoms of thromboembolism in factor V Leiden patients.
Non‐minimum‐phase wavelet estimation using second‐ and third‐order moments
Authors: Lu Wenkai
Published: December 2004

This paper presents a new algorithm for estimating non‐minimum‐phase seismic wavelets by using the second‐ and higher‐order statistics (HOS) of the wavelets. In contrast to many, if not most, of the HOS‐based methods, the proposed method does not need to assume that subsurface seismic reflectivity is a non‐Gaussian, statistically independent and identically distributed random process. The amplitude and phase spectra of the wavelets are estimated, respectively, using the second‐order statistics (SOS) and third‐order moment (TOM) of the wavelets, which will, in turn, be derived from the HOS of the seismic traces. In our approach, the wavelets can be ‘calculated’ from seismic traces efficiently; no optimization or inversion is necessarily required. Very good results have been obtained by applying this method to both synthetic and real‐field data sets.
Airborne gravimetry using a strapped‐down LaCoste and Romberg air/sea gravity meter system: a feasibility study
Authors: Verdun J. , Klingelé E.E.
Published: December 2004

Marine gravimeters mounted on stabilized platforms are commonly used in aircraft to perform airborne gravity measurements. The role of the stabilized platform is to level the sensor mechanically, whatever the aircraft attitude. However, this compensation is generally insufficient due to the sensitivity of modern gravity sensors. Correcting the offlevel error requires that an offlevel correction calculated from positioning data be added to gravimeter measurements, which complicates not only the processing, but also the assessment of precision and resolution.

This paper is a feasibility study describing the levelling of a completely strapped‐down LaCoste and Romberg gravimeter for airborne gravimetry operation, by means of GPS positioning data. It focuses on the calculation of the sensor offlevel correction needed for the complete gravity data processing. The precision of the offlevel correction that can be achieved, in terms of GPS data precision and gravity wavelengths, is theoretically studied and estimated using the gravity and GPS data acquired during the Alpine Swiss French airborne gravity survey carried out in 1998 over the French Western Alps. While a 1 cm precision of GPS‐determined baseline coordinates is sufficient to achieve a 5 mGal precision of the offlevel correction, we maintain that this precision has to reach 1 mm to ensure a 1 mGal precision of the offlevel correction at any wavelength.

Without a stabilized platform, the onboard instrumentation becomes significantly lighter. Furthermore, the correction for the offlevel error is straightforward and calculated only from GPS data. Thus, the precision and the resolution of airborne gravity surveys should be estimated with a better accuracy.
Electromagnetic fields in a steel‐cased borehole
Authors: Lee Ki Ha , Kim Hee Joon , Uchida Toshihiro
Published: December 2004

The development of an electromagnetic numerical modelling scheme for a magnetic dipole in an arbitrary casing segment in an inhomogeneous conductivity background has been difficult, due to the very high electrical conductivity and magnetic permeability contrasts between the steel casing and the background medium. To investigate the effect of steel casing efficiently, we have developed an accurate but simple finite‐element modelling scheme to simulate electromagnetic fields in a medium of cylindrically symmetric conductivity structures. In order to preserve the cylindrical symmetry in the resulting electromagnetic fields, a horizontal loop current source is used throughout. One of the main advantages of the approach is that the problem is scalar when formulated using the azimuthal electric field, even if the casing is both electrically conductive and magnetically permeable. Field calculations have been made inside the cased borehole as well as in another borehole which is not cased. Careful analyses of the numerical modelling results indicate that the anomaly observed in a cross‐borehole configuration is sensitive enough to be used for tomographic imaging.
Relationship between small‐scale structural variability and simulated vegetation productivity across a regional moisture gradient in southern Africa
Authors: Caylor K.K. , Dowty P.R. , Shugart H.H. , Ringrose S.
Published: December 2004

The observed variability in vegetation structure within landscapes was used as the basis for model estimates of the range of annual productivity of landscape patches at four sites along a moisture gradient in southern Africa ranging from 879 to 365 mm mean annual rainfall. Principal components of patch‐scale variability in leaf area, woody biomass and vertical leaf profiles were derived from intensive characterization of the small‐scale spatial structure of woody vegetation at each site. For each site, the mean and extremes of the principal component distribution parameterized an ecophysiology model of vegetation productivity. Vegetation was most heterogeneous at intermediate locations along the rainfall gradient. Variability in vegetation structure led to a range of annual productivity within one site (600 mm) that accounted for 68% of the total range in mean productivity across all sites. Patch‐scale estimates of tree productivity were found to be primarily correlated to annual rainfall (r2=0.66, P=0.001) and not woody leaf area (r2=0.01, P=0.75), while grass productivity was found to be related to values of woody leaf area (r2=0.77, P<0.001) and not annual rainfall (r2=0.11, P=0.29). This result indicates that life‐form interactions have a significant role in controlling vegetation productivity across the rainfall gradient. The findings of this study emphasize the importance of considering heterogeneity rather than mean structure when modeling productivity, particularly when considering dynamic vegetation structure, where differences between landscape patches may not be well represented in the mean structure.
Root production is determined by radiation flux in a temperate grassland community
Authors: Edwards Everard J. , Benham David G. , Marland Louise A. , Fitter Alastair H.
Published: December 2004

Accurate knowledge of the response of root turnover to a changing climate is needed to predict growth and produce carbon cycle models. A soil warming system and shading were used to vary soil temperature and received radiation independently in a temperate grassland dominated by Holcus lanatus L. Minirhizotrons allowed root growth and turnover to be examined non‐destructively. In two short‐term (8 week) experiments, root responses to temperature were seasonally distinct. Root number increased when heating was applied during spring, but root death increased during autumnal heating. An experiment lasting 12 months demonstrated that any positive response to temperature was short‐lived and that over a full growing season, soil warming led to a reduction in root number and mass due to increased root death during autumn and winter. Root respiration was also insensitive to soil temperature over much of the year. In contrast, root growth was strongly affected by incident radiation. Root biomass, length, birth rate, number and turnover were all reduced by shading. Photosynthesis in H. lanatus exhibited some acclimation to shading, but assimilation rates at growth irradiance were still lower in shaded plants. The negative effects of shading and soil warming on roots were additive. Comparison of root data with environmental measurements demonstrated a number of positive relationships with photosynthetically active radiation, but not with soil temperature. This was true both across the entire data set and within a shade treatment. These results demonstrate that root growth is unlikely to be directly affected by increased soil temperatures as a result of global warming, at least in temperate areas, and that predictions of net primary productivity should not be based on a positive root growth response to temperature.
Large‐scale plant light‐use efficiency inferred from the seasonal cycle of atmospheric CO2
Authors: Still Christopher J. , Randerson James T. , Fung Inez Y.
Published: December 2004

We combined atmospheric CO2 measurements, satellite observations, and an atmospheric transport model in an inverse modeling framework to infer a key property of vegetation physiology, the light‐use efficiency (LUE) of net primary production, for large geographic regions. We find the highest LUE in boreal regions and in the northern hemisphere tropics. Within boreal zones, Eurasian LUE is higher than North American LUE and has a distinctly different seasonal profile. This longitudinal asymmetry is consistent with ecological differences expected from the much greater cover of deciduous vegetation in boreal Eurasia caused by the vast Siberian forests of the deciduous conifer, Larch. Inferred LUE of the northern hemisphere tropics is also high and displays a seasonal profile consistent with variations of both cloud cover and C4 vegetation activity.