bluuebunny/crossref_metadata_2025 huggingface dataset:
A spectrometer for high-resolution and high-contrast Brillouin spectroscopy in the ultraviolet
Authors: Benassi Paola , Eramo Roberto , Giugni Andrea , Nardone Michele , Sampoli Marco
Published: December 2004

We present a multiple-grating spectrometer designed for high-resolution and high-contrast low-frequency scattering spectroscopy in the ultraviolet, as well as in the visible spectral regions. The instrument has a resolution better than 1 GHz and a contrast of about 1×10−10 both in the visible and in the UV range, thus doubling the highest resolution achieved by double-monochromator double-pass spectrometers such as the SOPRA DMDP2000, conceived for Raman–Brillouin spectroscopy using visible excitation. Performance tests and the Brillouin spectra obtained in the ultraviolet range are reported. Ray tracing results, aiming to give a better insight on the instrument performances are also presented. The instrument opens the possibility to study a new region of the exchanged momentum with a suitable energy resolution and to investigate the spectrum of density fluctuations in materials where the UV penetration depth could be a relevant step for the experimental study of the dynamics of disordered material.
Alternative calibration techniques for high-speed pyrometers in shock experiments
Authors: Partouche-Sebban D. , Holtkamp D. B. , Rodriguez P. , Stone J. B. , Borror S. D. , Kruschwitz C. A. , Young J. A.
Published: December 2004

Optical pyrometry is widely used in industry and research laboratories to perform surface temperature measurements of sample materials. These shock physics experiments are normally conducted at powder or gas gun facilities or at facilities where high explosives can be used as a shock wave source, and using high-speed pyrometers that are usually calibrated by using a blackbody source. But, electrical power, time, and space can be limiting factors in such facilities, and blackbody calibration can be difficult. Crucial parts of the experimental setup (fibers, lenses, and/or mirrors) are destroyed in such experiments, and the pyrometry system must be recalibrated before each experiment. We have developed a calibration technique using integrating-sphere sources that allows us to calibrate pyrometers more rapidly and easily than with blackbodies. Two different integrating-sphere systems are described to cover the wavelength range generally used in pyrometry studies. The characterization of these systems is fully detailed including measurements of their spectral radiances. A discussion of the advantages and drawbacks of both calibration sources is given.
Similarity in the far field of a turbulent round jet
Authors: Burattini P. , Antonia R. A. , Danaila L.
Published: December 2004

In this paper, we test the idea of equilibrium similarity, for which all scales evolve in a similar way in a turbulent round jet, for a prescribed set of initial conditions. Similarity requirements of the mean momentum and turbulent energy equations are reviewed briefly but the main focus is on the velocity structure function equation, which represents an energy budget at any particular scale. For similarity of the structure function equation along the jet axis, it is found that the Taylor microscale λ is the relevant characteristic length scale. Energy structure functions and spectra, measured at a number of locations along the axis of the jet, support this finding reasonably well, i.e., they collapse over a significant range of scales when normalized by λ and the mean turbulent energy ⟨q2⟩. Since the Taylor microscale Reynolds number Rλ is approximately constant (≃450) along the jet axis, the structure functions and spectra also collapse approximately when the normalization uses either the Kolmogorov or integral length scales. Over the dissipative range, the best collapse occurs when Kolmogorov variables are used. The use of ⟨q2⟩ and the integral length scale L provides the best collapse at large separations. A measure of the quality of collapse is given.
Development of an ion energy mass spectrometer for application on board three-axis stabilized spacecraft
Authors: Yokota Shoichiro , Saito Yoshifumi , Asamura Kazushi , Mukai Toshifumi
Published: December 2004

We have developed an ion energy mass spectrometer for use aboard three-axis stabilized spacecraft. This spectrometer measures the three-dimensional distribution function of mass-discriminated ions with a high sampling rate using electrostatic energy analysis and time-of-flight mass analysis. Three-axis stabilized spacecraft make it difficult to obtain complete coverage of all possible plasma arrival directions. We have added angular scanning deflectors to a cylindrically symmetric analyzer to provide a hemispherical (2πstr) field of view. Ion analyzers need suitable sensitivity with respect to surrounding space plasma fluxes, whose intensities vary greatly depending especially on plasma regions such as the solar wind and the planetary magnetospheres. To obtain a wide range of sensitivity, we equipped the analyzer with sensitivity control electrodes. Ions originating from planetary atmosphere and surface include various ion species such as Na+, Mg+, Al+, and Fe+. The time-of-flight device of our spectrometer applies a peculiar electric field, called a linear electric field, which increases linearly with the penetration length of incident ions to enable mass resolution higher than that of conventional time-of-flight techniques. In this electric field, ions bounce in simple harmonic motion, where the energy and flight path no longer affect the flight time and thus the mass resolution. We have designed and fabricated the ion energy mass spectrometer, and have evaluated its performance through laboratory experiments.
Particle-in-cell simulations of heat flux driven ion acoustic instability
Authors: Detering F. , Rozmus W. , Brantov A. , Bychenkov V. Yu. , Capjack C. E. , Sydora R.
Published: December 2004

The return current instability of ion acoustic waves in a laser heated plasma is studied by means of a collisional particle-in-cell code and theoretical analysis in the regime of nonlocal heat transport. The physical scenario of localized, inverse Bremsstrahlung heating in a single laser hot spot, electron thermal transport, return current of cold electrons, instability of ion acoustic waves, and resulting ion acoustic turbulence are examined in a self-consistent kinetic collisional particle simulation. The observed growth of the return current instability is in excellent agreement with predictions of a linear, nonlocal theory. Ion acoustic fluctuations contribute to the inhibition of thermal transport, which leads to the enhancement of the electron temperature in the center of a hot spot. Increased electron collisionality and hot ion tail production are the dominant saturation mechanisms of the return current instability in a one-dimensional geometry. The effects of the ion acoustic turbulence on other interaction processes are also discussed.
Carboniferous fireworms (Amphinomida : Annelida), with a discussion of species taxa in palaeontology
Authors: Pleijel Fredrik , Rouse Greg W. , Vannier Jean
Published: December 2004

New records of Palaeocampa anthrax Meek&Worthen, 1865 with fossilized soft parts are provided from Montceau-les-Mines in France, late Carboniferous, permitting the identification of a new clade of extinct amphinomid polychaetes. The group also provides an object lesson for problems with species concepts in palaeontology. The biological species concept, the diagnosable phylogenetic species concepts, and the monophyletic phylogenetic species concepts are applied and discussed in the case of P. anthrax, as well as more generally in palaeontology. All three are rejected, but for different reasons. Instead we advocate the application of LITUs (least inclusive taxonomic unit), which refers to the smallest currently recognised taxa, but without making the unjustified rank assignments to species.
The systematics of a new endemic Australian genus of ant spiders Masasteron (Araneae : Zodariidae)
Authors: Baehr B. C.
Published: December 2004

A new Australian zodariid genus Masasteron, gen. nov. is proposed for 20 newly described and one known species belonging to the following seven species-groups: Masasteron mas-group: M. bennieae, sp. nov., M.�bipunctatum, sp. nov., M. mas (Jocqué, 1991), M. ocellum, sp. nov., and M. queensland, sp. nov. Masasteron maini-group: M. maini, sp. nov., and M. tuart, sp. nov. Masasteron deserticola-group: M. clifton, sp. nov., M.�deserticola, sp. nov., and M. derby, sp. nov. The remaining four species-groups form the M. complector-clade. Masasteron mackenziei-group: M. mackenziei, sp. nov., and M. sampeyae, sp. nov. Masasteron burbidgei-group: M.�burbidgei, sp. nov. and M. haroldi, sp. nov. Masasteron darwin-group: M. barkly, sp. nov., M. darwin, sp. nov., and M. utae, sp. nov. Masasteron complector-group: M. complector, sp. nov., M. gracilis, sp. nov., M. piankai, sp.�nov. and M. tealei, sp. nov. Most new species are described from specimens of both sexes, but M. bennieae, sp.��nov., M. tuart, sp. nov., M. derby, sp. nov., M. mackenziei, sp. nov., M. haroldi, sp. nov., M. darwin, sp. nov., M.�utae, sp. nov. and M. gracilis, sp. nov. are known only from males. The possible relationships of the Masasteron species-groups are analysed with NONA and also reconstructed applying the original Hennigian method. The��results indicate that the genus Masasteron, gen. nov. is monophyletic, but closely related to Euasteron (Baehr,�2003a). Additional keywords: Zodariidae, Masasteron, new species from Australia
Win–stay, lose–shift in language learning from peers
Authors: Matsen Frederick A. , Nowak Martin A.
Published: December 2004

Traditional language learning theory explores an idealized interaction between a teacher and a learner. The teacher provides sentences from a language, while the learner has to infer the underlying grammar. Here, we study a new approach by considering a population of individuals that learn from each other. There is no designated teacher. We are inspired by the observation that children grow up to speak the language of their peers, not of their parents. Our goal is to characterize learning strategies that generate “linguistic coherence,” which means that most individuals use the same language. We model the resulting learning dynamics as a random walk of a population on a graph. Each vertex represents a candidate language. We find that a simple strategy using a certain aspiration level with the principle of win–stay, lose–shift does extremely well: stay with your current language, if at least three others use that language; otherwise, shift to an adjacent language on the graph. This strategy guarantees linguistic coherence on all nearly regular graphs, in the relevant limit where the number of candidate languages is much greater than the population size. Moreover, for many graphs, it is sufficient to have an aspiration level demanding only two other individuals to use the same language.
14-3-3 γ associates with muscle specific kinase and regulates synaptic gene transcription at vertebrate neuromuscular synapse
Authors: Strochlic Laure , Cartaud Annie , Mejat Alexandre , Grailhe Régis , Schaeffer Laurent , Changeux Jean-Pierre , Cartaud Jean
Published: December 2004

The muscle-specific receptor tyrosine kinase (MuSK) is part of a receptor complex, activated by neural agrin, that orchestrates the differentiation of the neuromuscular junction (NMJ). To gain insight into the function of the MuSK complex, we have developed a proteomic approach to identify new MuSK partners. MS analysis of MuSK crosslink products from postsynaptic membranes of the
Torpedo
electrocytes identified the adaptor protein 14-3-3 γ. The 14-3-3 γ protein was found localized at the adult rat NMJ. Cotransfection experiments in COS-7 cells showed that MuSK codistributed with the 14-3-3 γ protein at the plasma membrane. Furthermore, 14-3-3 γ was copurified by affinity chromatography with MuSK from transfected COS-7 cells and myotubes. The 14-3-3 γ protein did not colocalize with agrin-elicited acetylcholine receptor (AChR) aggregates in cultured myotubes, suggesting that it is not involved in AChR clustering. Expression of 14-3-3 γ specifically repressed the transcription of several synaptic reporter genes in cultured myotubes. This repression was potentiated by MuSK expression. Moreover, the expression of 14-3-3 γ in muscle fibers
in vivo
caused both the repression of synaptic genes transcription and morphological perturbations of the NMJ. Our data extend the notion that, apart from its well documented role in AChR clustering, the MuSK complex might also be involved in the regulation of synaptic gene expression at the NMJ.
Self-referential phase reset based on inferior olive oscillator dynamics
Authors: Kazantsev V. B. , Nekorkin V. I. , Makarenko V. I. , Llinás R.
Published: December 2004

The olivo-cerebellar network is a key neuronal circuit that provides high-level motor control in the vertebrate CNS. Functionally, its network dynamics is organized around the oscillatory membrane potential properties of inferior olive (IO) neurons and their electrotonic connectivity. Because IO action potentials are generated at the peaks of the quasisinusoidal membrane potential oscillations, their temporal firing properties are defined by the IO rhythmicity. Excitatory inputs to these neurons can produce oscillatory phase shifts without modifying the amplitude or frequency of the oscillations, allowing well defined time-shift modulation of action potential generation. Moreover, the resulting phase is defined only by the amplitude and duration of the reset stimulus and is independent of the original oscillatory phase when the stimulus was delivered. This reset property, henceforth referred to as selfreferential phase reset, results in the generation of organized clusters of electrically coupled cells that oscillate in phase and are controlled by inhibitory feedback loops through the cerebellar nuclei and the cerebellar cortex. These clusters provide a dynamical representation of arbitrary motor intention patterns that are further mapped to the motor execution system. Being supplied with sensory inputs, the olivo-cerebellar network is capable of rearranging the clusters during the process of movement execution. Accordingly, the phase of the IO oscillators can be rapidly reset to a desired phase independently of the history of phase evolution. The goal of this article is to show how this selfreferential phase reset may be implemented into a motor control system by using a biologically based mathematical model.
TBX21
: A functional variant predicts improvement in asthma with the use of inhaled corticosteroids
Authors: Tantisira Kelan G. , Hwang Eun Sook , Raby Benjamin A. , Silverman Eric S. , Lake Stephen L. , Richter Brent G. , Peng Stanford L. , Drazen Jeffrey M. , Glimcher Laurie H. , Weiss Scott T.
Published: December 2004

TBX21
encodes for the transcription factor T-bet (T-box expressed in T cells), which influences naïve T lymphocyte development and has been implicated in asthma pathogenesis. Specifically, the T-bet knockout mouse spontaneously develops airway hyperresponsiveness and other changes consistent with asthma. Because airway responsiveness is moderated by the use of inhaled corticosteroids in asthma, it is conceivable that genetic variation in
TBX21
may alter asthma phenotypes in a treatment-specific fashion. Here we demonstrate that the nonsynonymous variation in
TBX21
coding for replacement of histidine 33 with glutamine is associated with significant improvement in the PC
20
(a measure of airway responsiveness) of asthmatic children in a large clinical trial spanning 4 years. We note that this increase occurs only in the children randomized to inhaled corticosteroids and that it dramatically enhances the overall improvement in PC
20
associated with inhaled corticosteroid usage. The average PC
20
at trial end for subjects on inhaled corticosteroids possessing a variant allele was in the normal range for nonasthmatics. In cellular models, we show that the
TBX21
variant increases T helper 1 and decreases T helper 2 cytokine expression comparably with wild type.
TBX21
may thus be an important determinant pharmacogenetic response to the therapy of asthma with inhaled corticosteroids.
Earnings and Impression Management in Financial Reports: The Case of CEO Changes
Authors: Godfrey Jayne , Mather Paul , Ramsay Alan
Published: December 2004

This article examines earnings management, as well as the presentational format of graphs (impression management) in the financial reports of sixty‐three Australian listed public companies that changed chief executive officers (CEOs). Prior U.S. evidence generally suggests downward earnings management in the year of senior management changes and upward earnings management in the following year (Pourciau, 1993). We argue that new managers not only have incentives to manage earnings but also have similar incentives to manipulate the impressions created by graphs in financial reports. Examining earnings and impression management at the same time also provides an opportunity to distinguish between alternative explanations for any observed earnings management. In the year of CEO change, we hypothesize and find evidence of downward earnings management and some limited evidence of unfavourable impression management of the key financial variables (KFVs) graphed. As posited, we find evidence of upward earnings management and some evidence of favourable impression management in the year after a CEO change. These results are strongest for the subsample in which the CEO change was prompted by a resignation rather than a retirement.
A forest of papers: CHAGS 9
Authors: Kenrick Justin
Published: December 2004

Conference reviewed:

Justin Kenrick, A Forest of Papers CHAGS 9 (Ninth International Conference on Hunting and Gathering Societies), Edinburgh, 9–13 September 2002
The pleasurable art of nature
Authors: Povey Deborah
Published: December 2004

Books reviewed in this article:

Walter S. Gibson, Pleasant Places. The Rustic Landscape from Bruegel to Ruisdael

Erik de Jong, Nature and Art, Dutch Garden and Landscape Architecture, 1650–1740
From genius to genres
Authors: Edwards Clive
Published: December 2004

Books reviewed in this article:

Eileen Harris, The Genius of Robert Adam: His Interiors

Michael Snodin and John Styles, Design and the Decorative Arts Britain 1500–1900
Statistical Control for Road Pavements
Authors: Griffiths David , Gulati Chandra , Ollis Jim
Published: December 2004

Roads are assets vital to the economies of nations, particularly those with such low population density as Australia and New Zealand. The quality of road construction is of great importance. The application of statistical techniques to determining whether the construction of road pavement is being carried out to the design specification can be of great benefit to administrators and contractors. In this paper, a method is presented for obtaining control limits for a means chart when correlated observations are taken over a grid on a two‐dimensional surface. Data from a closely monitored road construction project are used to determine if the construction process can be considered ‘in control’. The nature of the correlation structure is determined using ARIMA models. The ultimate aim of the control charts and specifications is to control base course thickness. Controlling the pavement surfaces is a means to this end.
An Affine‐Invariant Generalization of the Wilcoxon Signed‐Rank Test for the Bivariate Location Problem
Authors: Larocque Denis , Tardif Serge , Eeden Constance van
Published: December 2004

This paper proposes an affine‐invariant test extending the univariate Wilcoxon signed‐rank test to the bivariate location problem. It gives two versions of the null distribution of the test statistic. The first version leads to a conditionally distribution‐free test which can be used with any sample size. The second version can be used for larger sample sizes and has a limiting χ22 distribution under the null hypothesis. The paper investigates the relationship with a test proposed by Jan & Randles (1994). It shows that the Pitman efficiency of this test relative to the new test is equal to 1 for elliptical distributions but that the two tests are not necessarily equivalent for non‐elliptical distributions. These facts are also demonstrated empirically in a simulation study. The new test has the advantage of not requiring the assumption of elliptical symmetry which is needed to perform the asymptotic version of the Jan and Randles test.
Minimal Basis for a Connected Markov Chain over 3 × 3 ×K Contingency Tables with Fixed Two‐Dimensional Marginals
Authors: Aoki Satoshi , Takemura Akimichi
Published: December 2004

This paper considers a connected Markov chain for sampling 3 × 3 ×K contingency tables having fixed two‐dimensional marginal totals. Such sampling arises in performing various tests of the hypothesis of no three‐factor interactions. A Markov chain algorithm is a valuable tool for evaluating P‐values, especially for sparse datasets where large‐sample theory does not work well. To construct a connected Markov chain over high‐dimensional contingency tables with fixed marginals, algebraic algorithms have been proposed. These algorithms involve computations in polynomial rings using Gröbner bases. However, algorithms based on Gröbner bases do not incorporate symmetry among variables and are very time‐consuming when the contingency tables are large. We construct a minimal basis for a connected Markov chain over 3 × 3 ×K contingency tables. The minimal basis is unique. Some numerical examples illustrate the practicality of our algorithms.
A “Civilised Amateur”: Edgar Holt and His Life in Letters and Politics
Authors: Griffen–Foley Bridget
Published: December 2004

Now largely forgotten, Edgar George Holt (1904–1988) was a leading journalist and public relations officer in the middle decades of twentieth–century Australia. This article examines his prominent journalistic career in the 1930s and 1940s, his presidency of the Australian Journalists’ Association, and his work as the Liberal Party of Australia's public relations officer from 1950 to the early 1970s. The article explores the evolution of his cultural and political views, considering how a literary aesthete and poet came to be at the forefront of the 1944 newspaper strike and then an important player in Australian conservative machine politics and the emerging industry of political public relations.
The Department of External Affairs, the ABC & Reporting of the Indonesian Crisis 1965–1969
Authors: Najjarine Karim , Cottle Drew
Published: December 2004

The Department of External Affairs took a keen interest in the manner in which Radio Australia reported events in Indonesia throughout the 1950s and 1960s. Radio Australia's high signal strength gave it a massive listening audience in the region. The attempted coup in Indonesia of 1965, its immediate aftermath, and the protracted power struggle that followed, triggered a period of cooperation and conflict between the Department and the Australian Broadcasting Commission over Radio Australia's reporting of events in Indonesia. During this time the Department received and acted upon advice from the Australian ambassador to Indonesia, Keith Shann, and, via Shann, received advice from the Indonesian Army on how it wanted the situation in Indonesia reported. This period is characterised by the Department's efforts to take over Radio Australia, and by cooperation between major western powers to coordinate information policy towards Indonesia. The Department also attempted to influence reporting of events in Indonesia by the Australian press and succeeded in convincing newspaper editors to report and editorialise in a manner sensitive to the Department's concerns.
Creating and Sustaining Innovation
Authors: Bartos Stephen
Published: December 2004

Address given to the ‘Public Sector Innovation Summit — an International Conference’, Grand Hyatt, Singapore, 2002.
Privatisation — A History and Survey of Changes in Organisation Structures, Cultural and Environmental Profiles
Authors: Gowland David , Aiken Max
Published: December 2004

This paper provides a brief history of changes after privatisation to organisational structures and cultural profiles of affected entities. It assesses the experience of change in the electricity industry in New Zealand, the Commonwealth Serum Laboratories and the State Electricity Commission of Victoria and then examines results of a survey of senior executives of organisations privatised in Australia between 1990 and 1998. These senior executives had access to knowledge of pre‐ and post‐privatisation conditions and their answers to a series of questions on organisational structure, cultural and environmental issues were analysed. The detailed answers involve limited areas of ‘no change’ but, critically, significant cultural changes relating to private ownership are established. These are summarised for readers' convenience by tables and discussed within the text.
Film Note
Authors: Gonce Richard A.
Published: December 2004

Film reviewed:

Peter Cohen, Homo Sapiens 1900
Time course of capillary structure changes in rat skeletal muscle following strenuous eccentric exercise
Authors: Kano Y. , Sampei K. , Matsudo H.
Published: December 2004

Aim:  We examined the time course of capillary structure changes in rat skeletal muscle at 1, 3 and 7 days after strenuous eccentric exercise.

Methods:  The right gastrocnemius muscles of anaesthetized male Wistar rats were subjected to 300 controlled eccentric contractions using electrical stimulation. The contralateral gastrocnemius muscle was used as control. All morphometric parameters were determined in in situ perfused gastrocnemius muscles in red (Gr, predominantly slow‐twitch fibre) and white (Gw, predominantly fast‐twitch fibre) portions.

Results:  Muscle fibre damage was evident on days 1, 3 and 7 in Gr (29.3–53.9% damaged fibres) and Gw (58.9–86.8% damaged fibres) of exercised legs. Electron micrographs of transverse sections did not display collapsed or obstructed capillaries in exercised legs, and capillary endothelial cells retained their normal structures. However, capillary luminal shapes and area were altered in exercised legs on days 1 and 3. The ratio between minimal and maximal capillary diameter in a transverse section (i.e. luminal ellipticity) significantly differed when comparing control (Gr, 0.75 ± 0.02; Gw, 0.79 ± 0.03) and exercised legs (Gr, 0.65 ± 0.03; Gw, 0.66 ± 0.04) at 1 day after exercise. The mean capillary luminal area was significantly increased in exercised legs after 1 day (Gw, +24.3%) and 3 days (Gr, +31.9%; Gw, +62.2%) compared with control.

Conclusion:  We conclude that (1) capillary endothelial cell structure was maintained in damaged muscles, (2) changes in capillary lumen shapes and distensibility occur in the degenerated muscle up to 3 days after the eccentric contraction period.
Ca2+‐activated Cl− current reduces transmural electrical heterogeneity within the rabbit left ventricle
Authors: Verkerk A. O. , Tan H. L. , Ravesloot J. H.
Published: December 2004

Objective:  Various cationic membrane channels contribute to the heterogeneity of action potential configuration between the transmural layers of the left ventricle. The role of anionic membrane channels is less intensively studied. We investigated the role of the Ca2+‐activated Cl− current, ICl(Ca), in transmural electrical heterogeneity.

Methods and Results:  We determined the density of ICl(Ca) and its physiological role in subepicardial and subendocardial ventricular myocytes of rabbit using the patch‐clamp technique. ICl(Ca) was measured as the 4,4′diisothiocyanatostilbene‐2,2′‐disulphonic acid (DIDS) sensitive current. The current–voltage relationships and the densities of ICl(Ca) were similar in subepicardial and subendocardial myocytes. However, the functional role of ICl(Ca) exhibited striking differences. In subendocardial myocytes, blockade of ICl(Ca) by DIDS increased action potential duration (APD) significantly at all measured stimulus frequencies (3.33–0.2 Hz). In subepicardial myocytes, ICl(Ca) blockade increased APD only at 3.33 Hz, but not at the lower stimulus frequencies. At 1 Hz, ICl(Ca) blockade in subepicardial myocytes only caused an APD increase when the transient outward K+ current, Ito1, was blocked.

Conclusions:  The densities and gating properties of ICl(Ca) are similar in subepicardial and subendocardial myocytes. ICl(Ca) contributes to APD shortening in subendocardial, but not in subepicardial myocytes except at 3.33 Hz. These differences in functional expression of ICl(Ca) reduce the electrical heterogeneity in rabbit left ventricle.
The imperial vision of Halford Mackinder
Authors: BLOUET BRIAN W
Published: December 2004

From 1899 to 1939, Halford Mackinder was active in imperial affairs. In 1899, the same year he climbed Mount Kenya, he set out the case for free trade. Rapidly he converted to imperial protectionism, left the Liberal Party and joined the Conservatives. Mackinder, along with his associates in the Conservative Party, Leo Amery and Lord Milner, promoted the cause of imperial unity and imperial preference in trade. During the period 1899–1903, Mackinder's evolving ideas about empire helped shape the Pivot paper, and he spelt out a prescription to avoid imperial decline: bind Britain and the Dominions into a League of Democracies with one fleet and one foreign policy, and encourage economic growth within the empire by a system of tariffs that promoted imperial trade. In Mackinder's parliamentary career (1910–22), his party was never in power and the Liberals retained free trade. Only after World War I, at the end of his parliamentary career, did Mackinder become active in imperial policy as chair of the Imperial Shipping Committee and the Imperial Economic Committee.
The geographical pivot of history and early twentieth century geopolitical culture
Authors: VENIER PASCAL
Published: December 2004

This article offers a re‐interpretation of the geographical pivot of history by setting it in the context of the international relations and strategic debates of the early twentieth century, and by engaging with the historiography of British foreign policy during the Edwardian period. The overall argument is that the prospective effort of Mackinder does not appear as merely speculative but is in fact rather well grounded in the fundamentals of British foreign policy and more directly relevant than hitherto assumed. Identifying a trend towards a shift in the equilibrium between land power and sea power, Mackinder emphasized – and perhaps over‐emphasized – a Russian threat to British interests but considered that Germany alone only posed a minor threat. Such analysis seems to be remarkably in tune with British geopolitical culture around 1904, and with the ideas of the British Prime Minister Arthur Balfour. The way in which Mackinder further stressed that a combination of the two main continental powers would represent a major peril for Britain has hitherto been treated rather dismissively. This article however shows how twice during the Russo‐Japanese War of 1904–5 Wilhelm II attempted to bring such an alliance about. This article attempts to reassess the actual impact of the geographical pivot of history and more broadly of Mackinder's thought, usually considered minimal, on British foreign policy before 1914. Finally, a number of issues that seem to deserve further attention are suggested, in particular that of the influence exerted by Mackinder before 1914, and that of the genesis of Mackinder's conception of the ‘pivot zone’ or ‘heartland’.
Patterns of ecstasy use in Australia: findings from a national household survey
Authors: Degenhardt Louisa , Barker Bridget , Topp Libby
Published: December 2004

Aim  To examine the patterns, correlates and context of ‘recent’ (preceding 12 months) ecstasy use using data from a nationally representative sample of Australians interviewed in 2001.

Design  Data were analysed from the 2001 National Drug Strategy Household Survey, a multi‐stage probability sample of Australians aged 14 years or older. The focus was on ecstasy use among 14–19‐year‐olds and 20–29‐year‐olds, as the prevalence of recent use is highest among these groups. Recent ecstasy users were compared to those who had not used in the preceding 12 months and those who had never tried ecstasy (‘others’) on a range of demographic and drug use variables. Comparisons were also drawn between the patterns and context of ecstasy use of the two groups of recent ecstasy users (users aged between 14–19 and 20–29 years).

Findings  In 2001, 6.1% of Australians aged 14 years or older reported life‐time ecstasy use, and 2.9% reported recent use. One in 10 (10.4%) of 20–29‐year‐olds and 5.0% of 14–19‐year‐olds had used ecstasy recently. Although there were few demographic differences between recent users and others, compared to those who had not recently used ecstasy, recent ecstasy users were more likely to have used a range of other drugs. Although recent ecstasy users of both age groups could be characterized as polydrug users, 20–29‐year‐old users were more likely to use other drugs concurrently with ecstasy.

Conclusions  Following cannabis and amphetamines, ecstasy is the third most widely used illicit drug in Australia. Other than a greater likelihood of having used other drugs, few demographic variables appear to distinguish recent ecstasy users from others. Australian users in their 20s use ecstasy within a context of greater polydrug use than those in their teens. Although most ecstasy users described a pattern of occasional use, minorities reported weekly use, and difficulties in reducing their use despite wishing to do so. There is a need to develop interventions to assist problematic ecstasy users to reduce their use should they wish to do so and to increase education about the potential risks of combining ecstasy with other drugs.
A postmarketing study of relative abuse liability of hypnotic sedative drugs
Authors: Jaffe Jerome H. , Bloor Roger , Crome Ilana , Carr Malcolm , Alam Farrukh , Simmons Arnol , Meyer Roger E.
Published: December 2004

Aims  To demonstrate the utility of postmarketing studies using in‐treatment drug and alcohol abusers as informants for assessing the relative abuse liability of sedative–hypnotic drugs.

Design  A survey was conducted that ascertained exposure to a variety of drugs with hypnotic/sedative properties and elicited subjective evaluations indicative of abuse liability.

Methods  Complete data were obtained from 297 admissions (78% male) to three addiction treatment sites in the United Kingdom. Subjects were asked 15 questions about 12 different drugs, including five benzodiazepines, three antidepressants, two non‐benzodiazepine hypnotics and two antihistamines (plus one fictitious drug). Three of the benzodiazepines (diazepam, nitrazipam, temazepam) emerged as having substantially more abuse liability than any of the other drugs tested, as revealed by higher scores on abuse liability items (purchased on street, taken to get high, like drug, potential for addiction to drug). The antihistamines (chlorpheniramine, diphenhydramine) had lowest abuse liability profiles, while the antidepressants (amitriptyline, fluoxetine, trazadone) and non‐benzodiazepine hypnotics (zolpidem, zopiclone) had similar profiles.

Conclusion  This pilot study suggests that postmarketing information on hypnotic drug use obtained from drug addicts entering treatment produces data consistent with other measures of abuse liability. The data suggest that the risk of misuse of newer non‐benzodiazepine hypnotics may be less than that of benzodiazepine drugs, and similar to that of sedating antidepressants. The new methodology may serve to clarify or validate premarketing abuse liability data, and may help to inform the regulatory process and physician practice.
Uptake and adherence to highly active antiretroviral therapy among HIV‐infected people with alcohol and other substance use problems: the impact of substance abuse treatment
Authors: Palepu Anita , Horton Nicholas J. , Tibbetts Nicole , Meli Seville , Samet Jeffrey H.
Published: December 2004

Aim  We examined the association of substance abuse treatment with uptake, adherence and virological response to highly active antiretroviral therapy (HAART) among HIV‐infected people with a history of alcohol problems.

Design  Prospective cohort study.

Methods  A standardized questionnaire was administered to 349 HIV‐infected participants with a history of alcohol problems regarding demographics, substance use, use of substance abuse treatment and uptake of and adherence to HAART. These subjects were followed every 6 months for up to seven occasions. We defined substance abuse treatment services as any of the following in the past 6 months: 12 weeks in a half‐way house or residential facility; 12 visits to a substance abuse counselor or mental health professional; or participation in any methadone maintenance program. Our outcome variables were uptake of antiretroviral therapy, 30‐day self‐reported adherence and HIV viral load suppression.

Findings  At baseline, 59% (205/349) of subjects were receiving HAART. Engagement in substance abuse treatment was independently associated with receiving antiretroviral therapy (adjusted OR; 95% CI: 1.70; 1.03–2.83). Substance abuse treatment was not associated with 30‐day adherence or HIV viral load suppression. More depressive symptoms (0.48; 0.32–0.78) and use of drugs or alcohol in the previous 30 days (0.17; 0.11–0.28) were associated with worse 30‐day adherence. HIV viral load suppression was positively associated with higher doses of antiretroviral medication (1.29; 1.15–1.45) and older age (1.04; 1.00–1.07) and negatively associated with use of drugs or alcohol in the previous 30 days (0.51; 0.33–0.78).

Conclusion  Substance abuse treatment was associated with receipt of HAART; however, it was not associated with adherence or HIV viral load suppression. Substance abuse treatment programs may provide an opportunity for HIV‐infected people with alcohol or drug problems to openly address issues of HIV care including enhancing adherence to HAART.
Anti‐hyperalgesic effect of octreotide in patients with irritable bowel syndrome
Authors: Schwetz I. , Naliboff B. , Munakata J. , Lembo T. , Chang L. , Matin K. , Ohning G. , Mayer E. A.
Published: December 2004

Background : Octreotide has been found to be beneficial in the treatment of chronic pain, although the mechanisms underlying its therapeutic effect are incompletely understood.

Aims : To assess the effect of octreotide on perceptual responses to rectal distension in irritable bowel syndrome patients and healthy controls at baseline and following the experimental induction of rectal hyperalgesia.

Methods : In study 1, rectal perception thresholds for discomfort were determined in seven irritable bowel syndrome patients and eight healthy controls on three separate days using a computer‐controlled barostat. Subjects received saline, low‐dose and high‐dose octreotide in a random double‐blind fashion. In study 2, perceptual responses to rectal distension were obtained in nine irritable bowel syndrome patients and seven controls before and after repetitive high‐pressure mechanical sigmoid stimulation.

Results : Octreotide increased the discomfort thresholds in irritable bowel syndrome patients, but not in controls, without changing rectal compliance. Repetitive sigmoid stimulation resulted in decreased rectal discomfort thresholds in the patient group only. In irritable bowel syndrome patients, octreotide prevented the sensitizing effect of repetitive sigmoid stimulation on rectal discomfort thresholds.

Conclusions : Octreotide effectively increased discomfort thresholds in irritable bowel syndrome patients, but not in controls, at baseline and during experimentally induced rectal hyperalgesia. These findings suggest that octreotide exerts primarily an anti‐hyperalgesic rather than analgesic effect on visceral perception.
Regional application of PnET‐N‐DNDC for estimating the N2O source strength of tropical rainforests in the Wet Tropics of Australia
Authors: Kiese Ralf , Li Changsheng , Hilbert David W. , Papen Hans , Butterbach‐Bahl Klaus
Published: December 2004

In contrast to the significant importance of tropical rainforest ecosystems as one of the major sources within the global atmospheric N2O budget (2.2–3.7 Tg N yr−1), regional estimates of their N2O source strength are still limited and highly uncertain. To contribute toward more reliable estimates of the N2O source strength of tropical rainforest ecosystems on a regional scale, we modified a process‐oriented biogeochemical model, PnET‐N‐DNDC, and parameterized it to simulate C and N turnover and associated N2O emissions in and from tropical rainforest ecosystems. Model modifications included: (1) new parameterizations associated with plant physiology and soil hydrology and the addition of algorithms relating daily leaf litterfall to water stress as well as to daily rainfall to account for the effects of heavy rainfall damage; (2) the development of a denitrifier activity index that depends on soil moisture conditions and influences N turnover by denitrification; and (3) the addition of a biological N fixation algorithm. Daily simulated N2O emissions based on site data were in good agreement (model efficiencies up to 0.83) with field observations in the Wet Tropics of Australia and Costa Rica. The model was even able to reproduce the highly dynamic pattern of N2O emissions with short‐term increases during the wet season. Sensitivity analyses demonstrated that the PnET‐N‐DNDC model was sensitive to changes in soil properties such as pH, clay content, soil organic carbon and climatic factors such as rainfall and temperature. By linking the PnET‐N‐DNDC model to a geographic information systems database, tropical rainforests in a 9000 km2 area of the Wet Tropics of Australia are estimated to emit 962 t N2O‐N yr−1 (2.4 kg N2O‐N ha−1 yr−1) between July 1997 and June 1998.
Do changes in climate patterns in wintering areas affect the timing of the spring arrival of trans‐Saharan migrant birds?
Authors: Gordo Oscar , Brotons Lluís , Ferrer Xavier , Comas Pere
Published: December 2004

The life cycles of plants and animals are changing around the world in line with the predictions originated from hypotheses concerning the impact of global warming and climate change on biological systems. Commonly, the search for ecological mechanisms behind the observed changes in bird phenology has focused on the analysis of climatic patterns from the species breeding grounds. However, the ecology of bird migration suggests that the spring arrival of long‐distance migrants (such as trans‐Saharan birds) is more likely to be influenced by climate conditions in wintering areas given their direct impact on the onset of migration and its progression. We tested this hypothesis by analysing the first arrival dates (FADs) of six trans‐Saharan migrants (cuckooCuculus canorus, swiftApus apus, hoopoeUpupa epops, swallowHirundo rustica, house martinDelichon urbicaand nightingaleLuscinia megarhynchos), in a western Mediterranean area since from 1952 to 2003. By means of multiple regression analyses, FADs were analysed in relation to the monthly temperature and precipitation patterns of five African climatic regions south of the Sahara where species are thought to overwinter and from the European site from where FADs were collected. We obtained significant models for five species explaining 9–41% of the variation in FADs. The interpretation of the models suggests that: (1) The climate in wintering quarters, especially the precipitation, has a stronger influence on FADs than that in the species' potential European breeding grounds. (2) The accumulative effects of climate patterns prior to migration onset may be of considerable importance since those climate variables that served to summarize climate patterns 12 months prior to the onset of migration were selected by final models. (3) Temperature and precipitation in African regions are likely to affect departure decision in the species studied through their indirect effects on food availability and the build‐up of reserves for migration. Our results concerning the factors that affect the arrival times of trans‐Saharan migrants indicate that the effects of climate change are more complex than previously suggested, and that these effects might have an interacting impact on species ecology, for example by reversing ecological pressures during species' life cycles.
The response of heterotrophic CO2flux to soil warming
Authors: Eliasson Peter E. , McMurtrie Ross E. , Pepper David A. , Strömgren Monika , Linder Sune , Ågren Göran I.
Published: December 2004

In a forest ecosystem at steady state, net carbon (C) assimilation by plants and C loss through soil and litter decomposition by heterotrophic organisms are balanced. However, a perturbation to the system, such as increased mean soil temperature, will lead to faster decay, enhancing CO2release from decomposers, and thus upsetting the balance. Recentin situexperiments have indicated that the stimulation of soil respiration following a step increase in annual average soil temperature declines over time. One possible explanation for this decline may be changes in substrate availability. This hypothesis is examined by using the ecosystem model G'DAY, which simulates C and nitrogen (N) dynamics in plants and soil.

We applied the model to observations from a soil‐warming experiment in a Norway spruce (Picea abies(L.) Karst.) stand by simulating a step increase of soil temperature. The model provided a good qualitative reproduction of the observed reduction of heterotrophic respiration (Rh) under sustained warming. The simulations showed how the combined effects of faster turnover and reduced substrate availability lead to a transient increase ofRh. The simulated annual increase inRhfrom soil was 60% in the first year after perturbation but decreased to 30% after a decade.

One conclusion from the analysis of the simulations is thatRhcan decrease even though the temperature response function for decomposition remains unchanged. G'DAY suggests that acclimation ofRhto soil warming is partly an effect of substrate depletion of labile C pools during the first decade of warming as a result of accelerated rates of mineralization. The response is attributed mainly to changing levels of C in pools with short time constants, reflecting the importance of high‐quality soil C fractions. Changes of the structure or physiology of the decomposer community were not invoked. Therefore, it becomes a question of definition whether the simulated dynamics of the declining response of CO2release to the warming should be named acclimation or seen as a natural part of the system dynamics.