bluuebunny/crossref_metadata_2025 huggingface dataset:
The Gender Wage Gap in Paid‐ and Self‐Employment in Australia
Authors: Eastough Kristy , Miller Paul W.
Published: September 2004

This paper presents an analysis of the gender wage gap in the highly regulated Australian labour market. It compares wage outcomes in the wage and salary sector with those for the self‐employed. Comparisons with the United States are provided. The large gender pay gap in self‐employment suggests that the aggregate gender wage differential will not be eliminated solely through wage determination for wage and salary earners. The greater gender wage gap in the self‐employed sector may reflect liquidity constraints that are more difficult for self‐employed women to overcome relative to self‐employed men. The comparisons with the United States suggest that women will experience deterioration in relative earnings as the Australian labour market is deregulated.
A Model of Employment in the Arts
Authors: Papandrea Franco , Albon Robert
Published: September 2004

The behaviour of artists appears to be influenced by non‐pecuniary benefits that lead to employment choices inconsistent with traditional expectations of labour supply theory. The paper develops a model of employment in the arts with similarities to the Harris‐Todaro model. Seemingly paradoxical results arise. For example, the model illustrates how an increase in wage rates for non‐artistic activity may lead to a reduction in the amount of non‐artistic activity and a commensurate increase in the amount of time devoted to artistic endeavours. Additionally, the model illustrates how individual work preferences of artists can lead to substantial underemployment in the arts.
Economic Development Indicators as Determinants of Medal Winning at the Sydney Olympics: An Extreme Bounds Analysis
Authors: Moosa Imad A. , Smith Lee
Published: September 2004

This paper examines the variables that determine the performance of countries at the Olympic Games as measured by a weighted sum of the medals won at the Sydney 2000 Games. While previous studies have identified the importance of a country's economic size and the resources available to sport, this paper examines nine more variables including the number of athletes representing each nation and some development indicators. Based on 2310 regressions, both traditional and restricted extreme bounds analysis show that only two variables are robust: the number of athletes and national expenditure on health. Thus, the final model recognises four explanatory variables that include these two as well as GDP and population.
The Atkinson Inequality Measure and its Sampling Properties: Bayesian and Classical Approaches
Authors: Chotikapanich Duangkamon , Creedy John
Published: September 2004

This paper examines several Bayesian methods of obtaining posterior probability density functions of the Atkinson inequality measure and its associated social welfare function, in the context of grouped income distribution data. The methods are compared with asymptotic standard errors. The role of the number of income classes is investigated using a simulated distribution. If only a small number of groups is available in published data, there is a clear gain from generating the posterior probability density function when using an explicit income distribution assumption. Even with a small number of groups, the Bayesian approach gives results that are close to the sample values obtained using the corresponding individual observations.
The Robustness of Cartels Facilitated by Anti‐Dumping Regulations
Authors: Ashiya Noriko
Published: September 2004

This study formulates Prusa's (1992) theory that anti‐dumping regulations facilitate the formation of cartels between an exporter and import‐competing firms. It demonstrates that interest rates and product differentiation are two key factors that may determine the robustness of the cartels. It builds a Bertrand duopoly model with differentiated products that explains how anti‐dumping regulations might encourage the creation of cartels. To highlight the circumstances under which an import‐competing firm is seriously hurt by dumped exports, this study adopts the following setting. First, both the exporter and the import‐competing firms sell only in the home market. Second, if the exporter's product is sold at a cheaper price than the product of an import‐competing firm in the home market, this is a sufficient condition to initiate an anti‐dumping petition. Although the setting might also provide the circumstances under which the anti‐dumping authority could be over‐protecting the import‐competing firm, it makes it possible to view the exporter as a predator. Since the setting enables the exporter to be free from the need to make profits in its own market, it sets a lower price for its product only if it decides to undertake predatory activities against an import‐competing firm.
Francesco Crispi and Italy's Pursuit of War against France, 1887–9
Authors: Duggan Christopher
Published: September 2004

This paper will examine the problems of nation‐building in Italy in later nineteenth century Italy, focusing principally on the ideas and policies of the man who dominated the country in the 1880s and 1890s, Francesco Crispi. It will be my contention that Crispi and many of his political contemporaries on both the left and the right were strongly conscious of the mobilising and nationalising potential of “the other”, and to an extent manipulated and deliberately exaggerated threats posed both by internal enemies — principally the Catholics and the socialists — and external enemies — above all France. Crispi's attitude to France and the French was complex and highly ambivalent, and I will suggest — using as evidence his speeches, writings, and political actions, above all when prime minister in 1887–91 — that there was an element of disingenuousness in his repeated claims that France was bent on destroying Italy. What Crispi was trying to do was to create a climate of tension that would not only bring the population together, but might also lead on to a war, in alliance with Germany — a war that would finally cement the country's “moral unity”.
The Origins of World History: Arnold Toynbee before the First World War
Authors: Martel Gordon
Published: September 2004

Arnold Toynbee's ambitious work A Study of History was a phenomenal publishing success in its day, but it came under severe criticism from academic historians. In recent years, there has been something of a Toynbee revival among the proponents of the growing discipline of world history. This article suggests that Toynbee makes a somewhat unlikely founding figure for the broadly liberal and cosmopolitan world history movement, and investigates the very particular origins of Toynbee's vision of world history in the intellectual world of the pre‐1914 British Empire, and especially in Toynbee's education at Winchester and Oxford.
Happiness and Toska: An Essay in the History of Emotions in Pre‐war Soviet Russia
Authors: Fitzpatrick Sheila
Published: September 2004

This article examines the question of what can be gained from an investigation of people's emotions in Stalin's Russia. Such an investigation is inevitably limited by the type of sources available. However, the available sources on Soviet subjectivity provide some evidence of both “official” Soviet emotions (such as enthusiasm and righteous anger against enemies) and less officially prescribed, but widespread, emotions, such as fear, melancholy (toska), malice (zlost') and personal happiness. This article focusses on accounts of happiness (schast'e) and the yearning sadness known as toska, a frequently encountered counterpart of the former. The civic obligation to express public, collective happiness impinged on the capacity to express private happiness: grief and melancholy could be expressed, as long as they were not connected to complaints about the régime.
Accomplices with Reservations: German Diplomats and the Preparation of the Polish Campaign of September 1939
Authors: Angelow Jürgen
Published: September 2004

This paper examines the role of the conservative foreign policy establishment in the decision‐making process leading to the Nazi invasion of Poland in September 1939. Post‐war statements by German diplomats portrayed the conservative elite as reluctant participants in Hitler's drive to war. However, an examination of the foreign policy views of German conservatives reveals a significant degree of convergence with Nazi goals in their desire to revise Germany's post‐Versailles borders with Poland. In order to understand the role of the German diplomatic elite, it is also necessary to understand the degree to which foreign policy was subject to the same “polycracy” of decision‐making instances that characterised the structure of the “Third Reich” in general. While Hitler had relied on the conservative elites, including the Foreign Ministry and the military, their influence on decision‐making was waning by 1938–1939.
Die Grünen and the Israeli‐Palestinian Conflict
Authors: Humphreys Andrea
Published: September 2004

This paper discusses the German Greens' recent policy on Israel and Palestine, from the beginning of the first red‐green federal government to the present. It looks at Green Foreign Minister Joschka Fischer's diplomatic role in the Middle East, and the Greens' current very “mild” policy with regards to Israel, especially when compared to earlier Green attitudes to the region. This is explained with reference to both the continuing relevance of German history to German foreign policy, and the constraints that participation in the federal coalition — and supplying Germany's Foreign Minister — place on the Greens. The influence of history and power on the German Greens is further illustrated by a comparison of German Green attitudes to Israel with the US Greens' much more critical position.
Brisbane and Federation: A Review Article
Authors: Johnson Murray
Published: September 2004

Our Federation: Brisbane Heritage Trail 1901. Edited by Rod Fisher et al.

Our Federation: Brisbane: Patriotism, Passion and Protest 1901. Edited by Barry Shaw

Our Federation: Brisbane through the News 1901. Edited by Katherine McConnel
Greatness as Measure? Recent Writings on the High Court of Australia
Authors: Ritter David
Published: September 2004

Owen Dixon. By P. Ayres

Oxford Companion to the High Court of Australia. Edited by T. Blackshield, M. Coper and G. Williams

The Brennan Legacy: Blowing the Winds of Legal Orthodoxy. By R. Creyke and P. Keyzer
Book Reviews
Authors: Davis Michael T.
Published: September 2004

David Collins: A Colonial Life. By John Currey

Brisbane: Squatters, Selectors and Surveyors. (Brisbane History Group Papers No 16) Edited by Rod Fisher and Jennifer Harrison

Beyond the Ladies Lounge: Australia's Female Publicans. By Clare Wright

Legacies of White Australia: Race, Culture, Nation. Edited by Laksiri Jayasuriya, David Walker and Jan Gothard

This War Never Ends: The Pain of Separation and Return. By Michael McKernan

Keeper of the Faith: A Biography of Jim Cairns. By Paul Strangio

Platypus and Parliament: The Australian Senate in Theory and Practice. By Stanley Bach

Unfolding History, Evolving Identity: The Chinese in New Zealand. Edited by Manying Ip

New Guinea: Crossing Boundaries and History. By Clive Moore

Erasmus in the Twentieth Century: Interpretations c.1920–2000. By Bruce Mansfield

Eighteenth‐Century British Erotica. Edited by Chris Mounsey and Rictor Norton

London Corresponding Society, 1792–1799. Edited by Michael Davis.

Robert Emmet and the Rebellion of 1798. By Ruán O'Donnell

Robert Emmet and the Rising of 1803. By Ruán O'Donnell

Wilhelminism and its Legacies. German Modernities and the Meanings of Reform, 1890–1930. Essays for Hartmut Pogge von Strandmann. Edited by Geoff Eley and James Retallack

Divided Lives: The Untold Stories of Jewish‐Christian Women in Nazi Germany. By Cynthia A. Crane.

Conqueror's Road: An Eyewitness Report of Germany 1945. By Osmar White

Conflict and Compromise in East Germany, 1971–1989: A Precarious Stability. By Jeannette Z. Madarász

The Tsarist Secret Police Abroad: Policing Europe in a Modernising World. By Fredric S. Zuckerman

“A Problem from Hell”: America and the Age of Genocide.
By Samantha Power

A History of Modern India, 1480–1959. Edited by Claude Markovitz; translated by Nisha George and Maggy Hendry

Power in Transition: The Peaceful Change of International Order. By Charles A. Kupchan, Emanuel Adler, Jean‐Marc Coicaud and Yuen Foong Khong

Reading Humanitarian Intervention: Human Rights and the Use of Force in International Law. By Anne Orford

Stories of Gay and Lesbian Immigration: Together Forever? By John Hart

The Dynamics of Political Crime. By Jeffrey Ian Ross

The Battle for Hearts and Minds: Using Soft Power to Undermine Terrorist Networks. Edited by Alexander T. J. Lennon

The Media and Neo‐Populism: A Contemporary Comparative Analysis. Edited by Gianpietro Mazzoleni, Julianne Stewart and Bruce Horsfield
Syntactic Structures Redux
Authors: Freidin Robert
Published: September 2004

Abstract.  This article extends Howard Lasnik's commentary in Syntactic Structures Revisited (2000) on Chomsky's transformational analyses of the verbal morphology system. It reviews Lasnik's critique of the transformational machinery in Syntactic Structures and shows how the problems he identifies are resolved under a more minimal theory of transformations that developed circa 1980. Considering the three central topics in the analysis of this system—the order and form of verbal elements, the main verb movement parameter, and the distribution of periphrastic do—it discusses some problems that arise in Lasnik's hybrid account and proposes a lexicalist alternative that eliminates the rules of affix hopping and do‐support.
What Educational Resources Do Students Need to Meet California's Educational Content Standards? A Textual Analysis of California's Educational Content Standards and Their Implications for Basic Educational Conditions and Resources
Authors: Koski William S. , Weis Hillary Anne
Published: September 2004

This article examines the statutory and policy framework for California's standards-based reform and accountability scheme and argues that this scheme, not unlike others throughout the country, fails to ensure that all children are provided with the necessary resources and conditions to achieve at the high levels prescribed by the state's content standards. Although California has developed a comprehensive standards-based reform scheme that includes challenging educational content standards, curriculum frameworks tied to those standards, and accountability mechanisms that are based on performance on standards-based assessments, the state has never attempted to ascertain the basic educational resources and conditions to which all children should have access in order to achieve at the level of the state's content standards. In an effort to begin to fill that missing policy link, the article then summarizes a systematic analysis of the text of California's educational content standards and supporting materials, which analysis demonstrates that the state itself expects that children will have access to certain educational resources and conditions in four areas—facilities, technology, instructional materials, and teachers. Striking among the conclusions of the analysis is the extent to which California requires that children have access to modern technology, including computers, software, and the Internet. Less surprising, but no less important, is the extent to which the state's content standards assume that all children have access to quality facilities and instructional materials, ranging from laboratory equipment and sophisticated measuring instruments to well-stocked libraries and media centers. The article concludes by calling on the state to analyze its own content standards and curriculum frameworks to develop a complete basket of educational resources and conditions that all children should receive to have an opportunity to achieve the state's standards.
Education's Most Basic Tools: Access to Textbooks and Instructional Materials in California's Public Schools
Authors: Oakes Jeannie , Saunders Marisa
Published: September 2004

This article addresses critical issues regarding students’ access to textbooks, curriculum materials, equipment, and technology. Using California as a case, it reviews the importance of these instructional materials to education, generally, and in the context of current standards-based education policies. Based on data from a variety of sources, we find that textbooks, curriculum materials, and technology are educationally important and that the consequences of not having them are particularly harsh in a high-stakes, standards-based education system. We also find that many California students do not have the numbers or quality of textbooks, curriculum materials, and technology that they require to meet the content standards the state has set. Compounding the problem, shortages and poor quality of textbooks and instructional materials often exist in concert with other problematic school conditions—staffing shortages, facilities in disrepair, and overcrowding. Schools serving English learners and low-income students are most affected by shortages. A third set of findings details how actions by the state have either contributed to or failed to prevent students’ lack of access to textbooks, curriculum materials, and technology. Finally, considering California's own policies and those in other states, we conclude that California does have policy options that would be far more likely to ensure that all students have the texts and materials they need and/or detect and correct problems in the supply and quality of texts and materials when they occur.
Educational Equity and School Structure: School Size, Overcrowding, and Schools-Within-Schools
Authors: Ready Douglas D. , Lee Valerie E. , Welner Kevin G.
Published: September 2004

Consistent with the Williams v. California suit, our focus in this article is on educational equity, particularly the interface between equity and school organization. We concentrate on two structural issues, school size and school overcrowding, and one specific school structure, schools-within-schools. We organize the article as an interpretive summary of existing studies of these topics, concentrating on how these structural issues relate to social stratification in student outcomes, particularly academic achievement. Our evidence is drawn from both national studies and, when available and appropriate, from research that discusses the effects of school structure in California. We use this evidence to define which size high schools are best for all students (600–900 students), which responses to school overcrowding are appropriate (building more schools rather than adding portable classrooms or multitrack year-round schooling), and how creating smaller learning communities in high schools can work well for everyone by reducing the potential for internal stratification. California policies, however, have not promoted these responses. In many cases they have actually exacerbated inequality in educational outcomes and assisted the transformation of the social differences students bring to school into academic differences. We advocate reforms that are associated with high achievement and achievement that is equitably distributed by race, ethnicity, class, or family origin. Reforms that raise achievement of children at the lower end of the distribution without damaging those at the top are ones toward which we believe our nation should strive. By offering empirical evidence of practices that lead toward this important goal, we hope to inform the important debates surrounding the Williams case.
Essential Learning Conditions for California Youth: Educational Facilities
Authors: Ortiz Flora Ida
Published: September 2004

Ortiz begins with research showing that safe, healthy, and uncrowded school facilities are a basic ingredient of a good educational program. When teachers work in well-designed and highly functional school buildings, they are able to be more effective than when they must teach in inadequate facilities. Ortiz sets these findings against the evidence that a high proportion of California's educational facilities are inadequate because they are crowded, old, and in need of repair and modernization. She finds that pressures from increased enrollment in the state due to demographic changes and class size reduction, an average age of the state's school buildings of over 25 years, and the high cost of facilities have all contributed to the current inadequacies. However, the state's responses to the many problems with educational facilities have been severely limited by flaws in policies establishing the state's relationships with local districts with regard to funding, inventory, and oversight of educational facilities. The state has failed to establish a system of state financing to ensure that funds are available to and used by districts with schools in the poorest conditions. It has failed to promulgate minimum standards for school facility conditions and maintenance, develop systematic ways of monitoring conditions in schools throughout the state, or maintain effective investigation and correction processes when serious deficiencies are reported.
Seeking Equity in the Education of California's English Learners
Authors: Rumberger Russell W. , Gándara Patricia
Published: September 2004

The article provides an abridged version of a report prepared for the lawsuit, Williams v. State of California. The report first examines the achievement gap for English learners in California. Second, it reviews evidence in seven areas in which these students receive a substantially inequitable education vis-a-vis their English-speaking peers, even when those peers are similarly economically disadvantaged. Third, it documents the state's role in creating and perpetuating existing inequities. Finally, it describes a series of remedies that the state could pursue to reduce these inequities.
Associative learning in animals: A selective review of recent topics and contribution of Japanese researchers1
Authors: NAKAJIMA SADAHIKO
Published: September 2004

Abstract:  This article addressed several important topics in the field of associative learning in nonhuman animals: event contingency, associative retardation (learned helplessness and irrelevance), occasion setting, renewal of extinguished responses, acquired equivalence and distinctiveness, differential outcome effect, and retrospective inference. These topics have been studied with Pavlovian and instrumental conditioning preparations as behavioral test tubes for assessing animals’ cognitive abilities. The empiric data are suggesting highly cognitive abilities of animals in event processing. This article also reviewed studies conducted by Japanese psychologists taking the modern associationists approach. Although activities of Japanese researchers in this field of research are high, they are required to make a more unique contribution to the field.
Categorization and formation of equivalence classes in animals: Studies in Japan on the background of contemporary developments
Authors: JITSUMORI MASAKO
Published: September 2004

Abstract:  Recent studies on categorization and concept learning in nonhuman animals are described, sketching studies in Japan on the background of contemporary developments of the research field. The topics included are (1) similarity‐based perceptual concepts (open‐ended categories, categorical coherence, synthetic approach, prototype effects, levels of categorization); (2) functional equivalence between category members; and (3) non‐similarity‐based associative concepts (Sidman equivalence, mediated equivalence, emergent differential sample behavior, emergent matching by exclusion, integration of equivalence relations). The review suggests that studies in this field are continuing to contribute in the understanding of animal cognitive behavior and also to the contemporary developments of comparative psychology. The issues left open for future research are illustrated.
Logical and illogical behavior in animals1
Authors: YAMAZAKI YUMIKO
Published: September 2004

Abstract:  Not only humans but also nonhuman animals show logical and illogical behavior. There are two typical areas of evidence for this: transitive inference and the formation of equivalence relations. Transitive inference has been observed in a broad range of subjects, suggesting that they share the evolutionary reasons that support transitive inference. On the other hand, while the formation of equivalence relations is typically found in human subjects, it appears to occur rarely in nonhuman subjects. In the case of pigeons, even if they are trained explicitly in equivalence, they do not subsequently exhibit equivalence relations. The performance of the sea lion represents the most reliable evidence of equivalence relations in nonhumans, suggesting that species‐specific ecological properties support this particular cognition. These evidences suggest that in searching for the origin of logic, we should examine not only ontogenetic history, but also the phylogenetic history of the subjects.
Functional and structural pre‐adaptations to language: Insight from comparative cognitive science into the study of language origin1
Authors: OKANOYA KAZUO
Published: September 2004

Abstract: In this paper I propose hypotheses and strategies that can help integrating the comparative cognitive science and linguistics. First, I assume that language emerged by integrating several sub‐faculties and each of these sub‐faculties evolved gradually. These sub‐faculties probably evolved by reasons other than language, and thus they are pre‐adaptations to language. Second, I assume that language specific faculty does not exist but such a faculty is an emergent property from the integration of other sub‐faculties. For the partial verification of the correspondence between the assumed pre‐adaptation of a particular sub‐faculty in animals and the involvement of the sub‐faculty in the human language, I propose to utilize an external criterion such as the site of the brain activity. After explaining the research strategy, I attempted to provide accounts on several sub‐faculties and possible course of evolution by hypothesizing pre‐adaptations of each faculty. In conclusion, I argue that the comparative cognitive science is an important branch of the inquiry into the evolution of language.
Development of social cognition in infant chimpanzees (Pan troglodytes): Face recognition, smiling, gaze, and the lack of triadic interactions1
Authors: TOMONAGA MASAKI , TANAKA MASAYUKI , MATSUZAWA TETSURO , MYOWA‐YAMAKOSHI MASAKO , KOSUGI DAISUKE , MIZUNO YUU , OKAMOTO SANAE , YAMAGUCHI MASAMI K. , BARD KIM A.
Published: September 2004

Abstract: In this paper, we summarize a series of studies on the developmental changes in social cognition in mother‐raised infant chimpanzees from birth to around 2 years old. The infants preferentially tracked a photograph of their mother's face at 1 month but showed indifferent preferences to faces at 2 months old. This change in facial recognition was correlated with a decrease in neonatal spontaneous smiling, increase in social smiling and a decline in neonatal imitation of facial expressions. Also at around 2 months, the infants began to show preferences for directed‐gaze faces over averted gazes, and the amount of mutual gaze time between mother and infant chimpanzees increased. Thus, by 2 months of age, abilities required for dyadic interactions are already developed in chimpanzees as is the case in humans. The development of triadic interactions, however, is rather different between these two species. The infant chimpanzee can follow another's pointing or gaze at around 1 year, but even by 2 years old, does not “share” attention with the others.
Looking back: The “representational mechanism” of joint attention in an infant chimpanzee (Pan troglodytes)1
Authors: OKAMOTO SANAE , TANAKA MASAYUKI , TOMONAGA MASAKI
Published: September 2004

Abstract:  An infant chimpanzee's joint visual attention to objects behind him was investigated. A recent study has shown that a 13‐month‐old infant chimpanzee can follow human social cues including glancing (Okamoto, Tomonaga, Ishii, Kawai, Tanaka, & Matsuzawa, 2002a). In humans, 12‐month‐olds do not follow gaze to objects behind them but 18‐month‐olds do (Butterworth & Jarrett, 1991). In the present study, from 13 months old, the infant chimpanzee had been tested to look at one of two identical objects, which an experimenter indicated by pointing or head turning. The objects were set in front of or behind the subject. In our series of experiments, we used moving or stationary objects as targets. Moreover, the experimenter manipulated a computer at the onset of each block of trials. The results show that by the age of 20 months, the infant reliably followed the experimenter's cues and looked back to the target behind him. Moving targets elicited more responses than stationary targets, and the subject showed more follow responses after having seen the experimenter manipulating the computer.
Comparative cognition and neuroscience: Misconceptions about brain evolution
Authors: SHIMIZU TORU
Published: September 2004

Abstract:   This paper discusses five common misconceptions about the evolution of the brain. These misconceptions are: (1) brains evolved in a unilinear, serial process; (2) brain size increased linearly from simple to complex animals; (3) all the systems in the brain in different animals evolved at the same rate; (4) the “new” part of the brain became larger through evolution; and (5) the “same” brain structures in different animals attained the “same” functions. These misunderstandings must be corrected in order for comparative brain research to be a useful approach to understand the cognitive functions of different animals. This paper also discusses the growing interest in the integration of animal cognition studies and comparative brain research in the United States of America. In particular, two recent scientific meetings are presented as examples of the type of collaborations for exploring interdisciplinary brain research for comparative cognition.
Single‐channel activations and concentration jumps: comparison of recombinant NR1a/NR2A and NR1a/NR2D NMDA receptors
Authors: Wyllie David J. A. , Béhé Philippe , Colquhoun David
Published: September 2004

We have expressed recombinant NR1a/NR2A and NR1a/NR2D N‐methyl‐D‐aspartate (NMDA) receptor channels in Xenopus oocytes and made recordings of single‐channel and macroscopic currents in outside‐out membrane patches. For each receptor type we measured (a) the individual single‐channel activations evoked by low glutamate concentrations in steady‐state recordings, and (b) the macroscopic responses elicited by brief concentration jumps with high agonist concentrations, and we explore the relationship between these two sorts of observation.

Low concentration (5‐100 nM) steady‐state recordings of NR1a/NR2A and NR1a/NR2D single‐channel activity generated shut‐time distributions that were best fitted with a mixture of five and six exponential components, respectively. Individual activations of either receptor type were resolved as bursts of openings, which we refer to as ‘super‐clusters’.

During a single activation, NR1a/NR2A receptors were open for 36 % of the time, but NR1a/NR2D receptors were open for only 4 % of the time. For both, distributions of super‐cluster durations were best fitted with a mixture of six exponential components. Their overall mean durations were 35.8 and 1602 ms, respectively.

Steady‐state super‐clusters were aligned on their first openings and averaged. The average was well fitted by a sum of exponentials with time constants taken from fits to super‐cluster length distributions. It is shown that this is what would be expected for a channel that shows simple Markovian behaviour.

The current through NR1a/NR2A channels following a concentration jump from zero to 1 mM glutamate for 1 ms was well fitted by three exponential components with time constants of 13 ms (rising phase), 70 ms and 350 ms (decaying phase). Similar concentration jumps on NR1a/NR2D channels were well fitted by two exponentials with means of 45 ms (rising phase) and 4408 ms (decaying phase) components. During prolonged exposure to glutamate, NR1a/NR2A channels desensitized with a time constant of 649 ms, while NR1a/NR2D channels exhibited no apparent desensitization.

We show that under certain conditions, the time constants for the macroscopic jump response should be the same as those for the distribution of super‐cluster lengths, though the resolution of the latter is so much greater that it cannot be expected that all the components will be resolvable in a macroscopic current. Good agreement was found for jumps on NR1a/NR2D receptors, and for some jump experiments on NR1a/NR2A. However, the latter were rather variable and some were slower than predicted. Slow decays were associated with patches that had large currents.
Rhythmicity, synchronization and binding in human and primate motor systems
Authors: Farmer S. F.
Published: September 2004

This review focuses on recent advances in our understanding of temporal pattern coding in the motor systems of animals and man. Examples of millisecond time scale rhythmic synchronization in the visual system are considered. Results of experiments that demonstrate similar phenomena in the motor system are discussed. Finally problems concerning the nature of the correlation between neurophysiological signals and the relationship of correlation to motor behaviour are explored.
Activity‐dependent regulation of ‘on’ and ‘off’ responses in cat visual cortical receptive fields
Authors: Debanne Dominique , Shulz Daniel E. , Frégnac Yves
Published: September 2004

A supervised learning procedure was applied to individual cat area 17 neurons to test the possible role of neuronal co‐activity in controlling the plasticity of the spatial ‘on‐off’ organization of visual cortical receptive fields (RFs).

Differential pairing between visual input evoked in a fixed position of the RF and preset levels of postsynaptic firing (imposed iontophoretically) were used alternately to boost the ‘on’ (or ‘off’) response to a ‘high’ level of firing (S+ pairing), and to reduce the opponent response (respectively ‘off’ or ‘on’) in the same position to a ‘low’ level (S− pairing). This associative procedure was repeated 50‐100 times at a low temporal frequency (0.1‐0.15 s−1).

Long‐lasting modifications of the ratio of ‘on‐off’ responses, measured in the paired position or integrated across the whole RF, were found in 44 % of the conditioned neurons (17/39), and in most cases this favoured the S+ paired characteristic. The amplitude change was on average half of that imposed during pairing. Comparable proportions of modified cells were obtained in ‘simple’ (13/27) and ‘complex’ (4/12) RFs, both in adult cats (4/11) and in kittens within the critical period (13/28).

The spatial selectivity of the pairing effects was studied by pseudorandomly stimulating both paired and spatially distinct unpaired positions within the RF. Most modifications were observed in the paired position (for 88 % of successful pairings).

In some cells (n= 13), a fixed delay pairing procedure was applied, in which the temporal phase of the onset of the current pulse was shifted by a few hundred milliseconds from the presentation or offset of the visual stimulus. Consecutive effects were observed in 4/13 cells, which retained the temporal pattern of activity imposed during pairing for 5‐40 min. They were expressed in the paired region only.

The demonstration of long‐lasting adaptive changes in the ratio of ‘on’ and ‘off’ responses, expressed in localized subregions of the RF, leads us to suggest that simple and complex RF organizations might be two stable functional states derived from a common connectivity scheme.
The responsiveness of isolated human hand vein endothelial cells in normal pregnancy and in pre‐eclampsia
Authors: Mahdy Z. , Otun H. A. , Dunlop W. , Gillespie J. I.
Published: September 2004

Human hand vein endothelial cells were isolated from blood obtained by traumatic venepuncture. Cells were identified as endothelial by staining with endothelium‐specific antibodies. The subject groups studied were (i) non‐pregnant, (ii) pregnant (mean, 35 weeks gestation) and (iii) pre‐eclamptic women (mean, 36 weeks gestation).

Fura‐2 was used to measure agonist‐induced responses in intracellular Ca2+ in single endothelial cells isolated and maintained in vitro. All of the cells examined responded to adenosine triphosphate (ATP) with a large transient increase in Ca2+ followed by a sustained plateau.

The responses to ATP were significantly larger in the cells from pregnant women than in those from non‐pregnant and pre‐eclamptic women, but no other differences were observed. The amplitudes of the responses to ATP were (means ± s.e.m.) 0.56 ± 0.04, 1.42 ± 0.24 and 0.65 ± 0.09 fura‐2 ratio units for cells from non‐pregnant, pregnant and pre‐eclamptic subjects, respectively.

In cells isolated from non‐pregnant subjects, the amplitude of the responses to carbachol, histamine and bradykinin were all smaller than those activated by ATP: 5.1, 13.9 and 4.4 %, respectively. Not all cells responded to these agonists: 25 % responded to carbachol, 70.5 % responded to histamine and 12.5 % responded to bradykinin. Sixty‐five per cent of the cells from normotensive pregnant subjects responded to bradykinin compared with 25 % in the non‐pregnant and 13.9 % in the pre‐eclamptic subjects.

These data suggest that there may be differences in the responsiveness of venous endothelial cells in pregnancy and that pre‐eclamptic cells behave differently.
Muscular sense is attenuated when humans move
Authors: Collins D. F. , Cameron T. , Gillard D. M. , Prochazka A.
Published: September 2004

Muscle receptors play an important role in our conscious perception of movement, but there are no published accounts of our ability to detect their signals during different motor tasks. The present experiments introduce a method to test muscular sense when humans move.

Muscle receptors were excited by an electrically induced twitch of the right extensor carpi ulnaris muscle. The muscle was stimulated via percutaneously inserted intramuscular electrodes or using surface stimulation through anaesthetized skin. Muscular sense was represented by the ability to detect the twitch and was compared between various tasks and stationary control trials.

Three hertz voluntary wrist movements significantly attenuated muscular sense to 37 % of control. This velocity‐dependent attenuation was present over a range of twitch amplitudes suggesting it does not simply reflect a masking of low intensity stimuli. Perceptual ratings of twitch amplitude during fast imposed passive movements were reduced by 40 %, though this did not quite reach statistical significance. However, perceptual ratings of twitches evoked up to 2 s after the termination of the passive movements were significantly different from control.

Reaching with the stimulated, but not the contralateral, arm also significantly reduced muscular sense (to 40 %).

Attenuation to 58 % of control during cyclic stretching of the skin on the dorsum of the hand showed that signals from peripheral receptors may play a role. Attenuation prior to a single wrist flexion movement indicated that central sources can also contribute.

The results are consistent with current findings of a general attenuation of sensory feedback during movement and raise questions regarding the role of muscular sense in movement control.
Hyperpolarization‐activated cationic currents (Ih) in neurones of the trigeminal mesencephalic nucleus of the rat
Authors: Khakh Baljit S. , Henderson Graeme
Published: September 2004

We studied the voltage‐dependent current activated by membrane hyperpolarization in sensory proprioceptive trigeminal mesencephalic nucleus (MNV) neurones.

Membrane hyperpolarization (from ‐62 to ‐132 mV in 10 mV steps) activated slowly activating and non‐inactivating inward currents. The hyperpolarization‐activated currents could be described by activation curves with a half‐maximal activation potential (V½) of ‐93 mV, slope (k) of 8.4 mV, and maximally activated currents (Imax) of around 1 nA. The reversal potential of the hyperpolarization‐activated currents was ‐57 mV.

Extracellular Cs+ blocked hyperpolarization‐activated currents rapidly and reversibly in a concentration‐dependent manner with an IC50 of 100 μM and Hill slope of 0.8. ZD7288 (1 μM; 4‐(N‐ethyl‐N‐phenylamino)‐1,2‐dimethyl‐6‐(methylamino) pyridinium chloride), the compound developed as an inhibitor of the cardiac hyperpolarization‐activated current (If), also blocked the hyperpolarization‐activated currents in MNV neurones. Extracellular Ba2+ (1 mM) did not affect hyperpolarization‐activated currents. We tested whether the hyperpolarization‐activated currents contribute to the somatic membrane properties of MNV neurones by performing some experiments using current‐clamp recording. In such experiments application of Cs+ (1 mM) produced no effect on neuronal resting membrane potentials.

During the course of our experiments we noticed that activating ATP‐gated non‐selective cation channels (P2X receptors) caused an inhibition of Ih associated with a V½ shift of 10 mV in the hyperpolarizing direction. This P2X receptor‐mediated inhibition of Ih was blocked in recordings made with the rapid calcium chelator BAPTA (11 mM) in the pipette solution.

We conclude that the current activated by membrane hyperpolarization in MNV neurones is Ih on the basis of its similarity to Ih observed in other neuronal preparations. Activation of Ih can account for the anomalous time‐dependent inward rectification that has previously been described in MNV neurones.
Increased contribution of NR2A subunit to synaptic NMDA receptors in developing rat cortical neurons
Authors: Stocca Gabriella , Vicini Stefano
Published: September 2004

Pharmacologically isolated miniature NMDA receptor‐mediated excitatory postsynaptic currents (mN‐EPSCs) were recorded in large visual cortical neurons in layer V of rat cortical slices. Haloperidol (100 μm) and CP101,606 (10 μm), two specific blockers of NMDA receptors comprising NR1/NR2B subunits, were tested on mN‐EPSCs in rats at postnatal days 7 and 8 (P7–P8) and P13–P15. At both ages tested, no significant effects of these drugs were seen in the whole population of neurons, although in few neurons at both ages changes in amplitude were observed with haloperidol. Other dopamine receptor antagonists, spiperone and clozapine, failed to decrease mN‐EPSCs in cortical neurons at P13–P15.

CP101,606 (10 μm) significantly decreased the amplitude of evoked N‐EPSCs (eN‐EPSCs) in visual cortical slices from rats at P3–P5, a developmental stage at which mRNA studies have indicated the virtual absence of NR2A mRNA. CP101,606 failed to significantly change evoked AMPA‐mediated EPSCs at P5 and eN‐EPSCs at P7–P8 and P13–P15.

NMDA receptor‐mediated currents were also studied in somatic outside‐out patches at P13–P15 with fast application of l‐glutamate (1 mm). Haloperidol (50 μm) and CP101,606 (10 μm) blocked these currents in all patches tested. The effect of CP101,606 was concentration dependent.

We suggest that rather early in development synaptic receptors comprising NR1/NR2B subunits could be associated with other subunits so that blockade by haloperidol and CP101,606 is prevented. Moreover, the consistent blockade seen in outside out patches might be ascribed to the confinement of NR1/NR2B receptors to an extrasynaptic population.
An allosteric interaction between the NMDA receptor polyamine and ifenprodil sites in rat cultured cortical neurones
Authors: Kew James N. C. , Kemp John A.
Published: September 2004

The atypical NR2B subunit‐selective NMDA receptor antagonist ifenprodil was originally believed to act as a competitive antagonist at the polyamine binding site of the NMDA receptor. However, a number of studies have suggested that ifenprodil might bind to a distinct site.

Using whole‐cell voltage clamp recordings, we have studied the interaction of spermine with both ifenprodil and the related NR2B selective antagonist Ro 8–4304 at the NMDA receptor in rat cultured cortical neurones in the presence of saturating concentrations of glycine.

Ifenprodil and Ro 8‐4304 inhibited steady‐state currents evoked by 100 μm NMDA in the absence of spermine with IC50 values of 0.3 and 0.6 μm, respectively. In the presence of 1 and 3 mm spermine, IC50 values for ifenprodil were 1.4 and 1.8 μm and for Ro 8‐4304 they were 3.0 and 7.5 μm, respectively.

In the presence of spermine, the on‐time constant of receptor blockade by both antagonists was significantly slower than control and the off‐time constant of recovery from receptor blockade following removal of Ro 8‐4304 was significantly faster.

Fast application of spermine during an NMDA steady‐state current in the continuous presence of a subsaturating concentration of either antagonist resulted in a biphasic increase in the current, consistent with a fast increase upon spermine binding and a slow increase resultant from dissociation of antagonist due to spermine binding‐induced allosteric reduction in receptor antagonist affinity. In agreement with this, at higher, saturating concentrations of antagonist, the slow increase in current amplitude was markedly reduced or absent.

These observations are consistent with a non‐competitive, allosteric interaction between spermine and the antagonists, such that spermine binding to the NMDA receptor results in a reduction in receptor affinity for the antagonists and vice versa.

The effects of Mg2+ on the NMDA‐evoked currents and its interaction with ifenprodil were similar to those of spermine, supporting the suggestion that Mg2+ might be the physiological ligand acting at the spermine site mediating glycine‐independent stimulation.
Single‐channel currents of a peptide‐gated sodium channel expressed in Xenopus oocytes
Authors: Zhainazarov Aslbek B. , Cottrell Glen A.
Published: September 2004

Single‐channel recordings were made from outside‐out membrane patches of Xenopus oocytes injected with the cDNA clone FaNaCh, which encodes a peptide‐gated Na+ channel from Helix aspersa.

The natural peptides FMRFamide and FLRFamide only activated unitary currents in oocytes injected with FaNaCh; the EC50 values were 1.8 and 11.7 μm, respectively.

The slope conductance of the channel was 9.2 pS for both peptides.

With FMRFamide, the open probability (Po) of the channel was 0.06 at 0.3 μm and 0.76 at 30 μm, whereas for FLRFamide the open probability increased from 0.04 at 1.8 μm to 0.49 at 50 μm. The Hill coefficient was greater than 1 for both peptides.

High concentrations of each peptide evoked very fast flickering between open and closed states which led to decreased unitary current amplitude.

At low doses, brief single openings and bursts of longer openings occurred. With higher doses, the occurrence of the brief openings declined and the number of longer openings increased; the duration of the longer openings was shorter with FLRFamide than with FMRFamide.

For each peptide, frequency distribution histograms of open events were best fitted by the sum of two exponential components, suggesting the existence of two open states of the channel. Closed events were fitted by the sum of three components, suggesting the existence of three closed states.

The data were analysed according to a five‐state model in which the brief openings correspond to a single liganded open form of the channel and the longer openings to a doubly liganded open form. According to this interpretation, the greater whole‐cell response observed with FMRFamide than with FLRFamide results mostly from a slower closing rate constant for the longer (doubly liganded) channel openings.