bluuebunny/crossref_metadata_2025 huggingface dataset:
The new economy: a cultural history
Authors: Löfgren Orvar
Published: June 2003

Abstract In this article I look at some cultural aspects of the economic frenzy of the 1990s, a period often labelled ‘the new economy’. The focus is on the ways in which processes of culturalization became an important part of production, in such fields as e‐commerce and ‘the experience economy’. How was culture packaged and marketed in new ways, for example in the production of symbols, images, auras, experiences and events? I explore how the technologies of imagineering, performance, styling and design came to play important roles in this process. Other important traits of this development are discussed in a comparison with earlier examples of the emergence of ‘new economies’: the aesthetics and practices of speed, the cult of creativity, ‘the catwalk economy’ and the importance of public display and performance, as well as the importance of ‘newness’.
Rethinking migration, ancient to future
Authors: Sanjek Roger
Published: June 2003

Abstract Immigration as a framework in which to analyse the vast movements and interactions of people in the contemporary world tends to highlight recent movers and the legal apparatuses and ideologies of citizenship pertaining to them. Nation states, however, contain other, non‐immigrant groups whose circumstances of arrival in many cases preceded nation states or a fully embordered globe, and who also need foregrounding if ethnocultural political sentiments and the deeper meanings of postmodern ‘intermingling’ are to be understood. Surveying a wide‐ranging body of anthropological and historical studies of human migration and interaction over the past 150,000 years, a new synthetic framework is proposed. Contemporary nations all encompass diverse origins and arrivals that may be interpreted in terms of seven historically emergent and still ongoing processes: expansion, refuge‐seeking, colonization, enforced transportation, trade diaspora, labour diaspora and emigration. Together they define the complex terrains upon which contemporary immigrants arrive.
The cosmopolitan organization — an essay on corporate accountability
Authors: Garsten Christina
Published: June 2003

Abstract Transnational corporations increasingly seek to present a vision of social responsibility alongside the business vision. This reflects greater awareness of ‘the world as one single place’, of global risk scenarios, and the politics of doing business. There are also demands for greater transparency and accountability in corporate actions by state representatives, grassroots movements and organized consumers. Transnational corporations now aim to be socially responsible and to engage in ‘corporate citizenship’ by adhering to voluntary codes of conduct, social accountability standards, etc. This discourse of corporate accountability is part of a discourse of globality, or ‘globe talk’, a vital component of contemporary world culture, largely produced, diffused, and sustained by organizations with expansive ambitions of regulating global business; transnational corporations, business associations, international organizations, NGOs and INGOs. Awareness of the global nature of trade and capitalism, the associated risk scenarios, and the attempts at approaching something like a humane globalization by the setting up of ethics standards and codes of conduct, may be understood as a particular case of ‘worldism’. This ‘worldism’ is foundational, with universalizing and homogenizing claims. ‘Corporate citizenship’ and ‘accountability’ are therefore treated as a form of organizational culture that involves a particular kind of moral cosmopolitanism.
Closeted cosmopolitans: Israeli gays between centre and periphery
Authors: Shokeid Moshe
Published: June 2003

Abstract In this article I present observations of gay life conducted in Tel Aviv in 1993 and 1998. Despite the invisibility of gay venues and the absence of gay political action, the men studied in 1993 (mostly professionals and artists) nevertheless did not express resentment or a wish to move to the Western havens of gay life with which they had been acquainted as frequent travellers. However, the gay scene in Tel Aviv seemed very different a few years later. A number of leading gay men made a successful claim for public recognition and a growing constituency of gay men and women came out to demonstrate for minority rights and a share of public space. Rather than relating the growth of gay empowerment solely to the idea of globalization or ‘postmodernism’, in this article I seek to consider the social context in which these worldwide influences take place. The introduction of two stages of observation displays the dynamic nature of social phenomena that ethnographers might often confront in their present‐day research projects.
Overcoming temptation: on masculinity and sexuality among Muslims in Stockholm
Authors: Gerholm Lena
Published: June 2003

Abstract In this article I deal with transnational processes in contemporary Stockholm and focus on notions of masculinity and sexuality among transmigrant Arab Muslims. A key idea among the men is that their desires have to be controlled. Five ways to overcome temptations are presented: visions of paradise, polygamous marriages, storytelling, sermons in the mosque, and stereotyping Swedish women. The emphasis placed on resisting temptation is understood to be a result of transmigration and an expression of a gender‐based cultural logic. Men, in contrast to women, can restrain their desires and thereby also establish a stable relationship with God. For this reason they can both assume responsibility for public life and be the leaders of their families. The legitimate foundation of this power position is their ability to resist temptation.
The Value of Life and Health for Public Policy
Authors: Abelson Peter
Published: June 2003

Expenditure on health and safety is a substantial part of GDP, but public agencies in many countries, including Australia, have only qualitative views about the value of life and health. Also, despite considerable work by economists on the value of life and health in recent years, some important issues, such as the value of a healthy life‐year, remain unresolved. This paper presents a framework for valuing life and health. It then draws on international and Australian research to estimate possible values for life, healthy life‐years, and various chronic and acute health states for public policy purposes in Australia.
Computable General Equilibrium Model on Air Pollution Abatement Policies with Indonesia as a Case Study
Authors: Resosudarmo Budy Prasetyo
Published: June 2003

This paper is to develop an economic model that is appropriate to analyse the expected impact of air pollution policies on national economic performance and on household incomes for various socio‐economic groups. The model includes the impact of economic activities on air quality in urban areas as well as the impact of urban air quality on the economy. Application of this model in Indonesia suggests that an implementation of policies to improve urban air quality might also induce a higher GDP and increase the income of poor households in the country.
Geography: a different sort of discipline?
Authors: Johnston Ron
Published: June 2003

Debate continues about the inter‐relationships between human and physical geography and their different research and publication practices. Relatively little data about these are available, however. Using an analysis of all publications submitted by UK geographers to the 2001 Research Assessment Exercise, this paper identifies a substantial difference between human and physical geographers in their publication strategies. Most physical geographers place their research papers in specialized inter‐disciplinary journals and make relatively little use of geography outlets: most human geographers, on the other hand, publish in geography journals. Comparisons with other disciplines – in the earth and environmental and social sciences respectively – also identify differences between geographers and their peers. The overall conclusion is that, with regard to research and publication at least, UK geography cannot be presented as a single academic community with strong internal ties, but rather as a conglomerate of separate communities writing for different audiences.
Mark Melton's geomorphology and geography's quantitative revolution
Authors: Keylock Christopher J
Published: June 2003

Mark Melton published some important papers in the late 1950s that have had a significant influence upon the subsequent development of geomorphology. Two of these papers were published in the same journal in the same year, and have a similar number of total citations, and these are compared in this study. Although both papers present novel empirical findings and discuss innovative conceptual frameworks, the extent and manner to which they have been used within geography and geology differs quite markedly. This reveals marked differences in the conceptual frameworks and research priorities of the two groups of scientists, which may help explain why geomorphology has proceeded differently on the two sides of the Atlantic since the quantitative revolution.
Stubborn identities and the construction of socio‐spatial boundaries: ultra‐orthodox Jews living in contemporary Britain
Authors: Valins Oliver
Published: June 2003

Despite ultra‐Orthodoxy being the fastest growing component of the British Jewish community (and Jewry worldwide), it has received little academic coverage by geographers. This paper provides an in‐depth examination of a community of ultra‐Orthodox Jews in Broughton Park, Manchester. It maps out the residential concentration of these Jews and, using in‐depth qualitative interviews, discusses the construction of socio‐spatial boundaries that are used to define and mark out ‘them’ from ‘us’. Through this the paper contributes to wider geographic discussions about identity, segregation and religion. It shows how the power of religion to define people's beliefs and everyday practices remains, for certain groups, extremely strong.
Soil erosion and flooding on the eastern South Downs, southern England, 1976–2001
Authors: Boardman John
Published: June 2003

The South Downs in southern England have been farmed for 5000 years: the initial loess cover is now a thin, stony remnant as a result of erosion. During the 1980s, field monitoring of erosion events in an area of 36 km2showed that average rates of erosion are low (0.5–5.0 m3ha−1yr−1), but that occasional storms result in losses of over 200 m3ha−1yr−1on individual fields. On soils that are only 15 cm thick, such rates pose a threat to future farming. Almost all recent erosion has been on fields of winter cereals, which are bare in the wet autumn period. Of greater significance in the short term are the effects of soil‐laden runoff (or muddy floods) on urban areas. Flood damage to property has been a regular event since the conversion of this area to winter cereals in the 1970s. Soil conservation measures have been negligible and flood protection has consisted mainly of engineering works and limited land‐use change at sites where property damage has occurred. Conversion to grass under the Set Aside, and an Environmentally Sensitive Area (ESA) scheme, could be an effective soil conservation and flood protection approach. In the longer term, increasing stoniness of soils, the economic incentives for arable farming in marginal areas, and the success of legal proceedings relating to flood damage, will determine the future of erosion on the South Downs. Current farming systems clearly are unsustainable and would become more so under future climates without substantial site‐targeted land use change.
Telling small stories: spaces of knowledge and the practice of geography
Authors: Lorimer Hayden
Published: June 2003

This article examines how the practice of learning geography, and the arenas in which knowledge‐making takes place, can be usefully positioned within changing histories of the discipline. It contends that networks of action – understood through the intersection of social sites, subjects and sources – present a conceptual framework and narrative focus for the re‐consideration of specific episodes from geography's past. The interventions made here are informed and illustrated by a ‘small story’ about the doing of geography. Based on different personal accounts, the story revives a series of events, encounters, dialogues and images dating back to the winter of 1951 at Glenmore Lodge, Scotland. This educational institution in the Cairngorm mountains offered children from urban areas the opportunity to learn field studies and the skills of ‘outdoor citizenship’. Initially, the focus falls on Margaret Jack, a 14‐year‐old field‐course participant. Her learning experiences are traced through personal letters, a diary and a field journal dating from that time, and her recent recollections of this event. Margaret's account dovetails with the story of her field studies instructor, Robin Murray. Robin's role is traced through his learning experiences as a geography undergraduate at Aberdeen University, and the recent recollections of Catriona Murray, his wife.
River meander behaviour and instability: a framework for analysis
Authors: Hooke Janet
Published: June 2003

Recent empirical and theoretical work on river meanders suggests that instability is inherent. Within this context, an occurrence of multiple cut‐offs could be interpreted as a clustering associated with self‐organized criticality. Types of meander behaviour ranging from stable to chaotic are examined as trajectories or attractors within the phase space of rate of meander movement and bend curvature and change to the system is explored as shift from one attractor to another. It is suggested that this new approach provides insights into meander dynamics and provides a basis to identify the conditions, limits and constraints under which different behaviour occurs. Basic controls of energy and resistance underlie planform behaviour, but need to be refined in relation to the morphology and stability of channel courses.
Directed Walk Designs for Dose‐Response Problems with Competing Failure Modes
Authors: Hardwick Janis , Meyer Mary C. , Stout Quentin F.
Published: June 2003

Summary We examine adaptive allocation designs for the problem of determining the optimal therapeutic dose for subjects in early‐phase clinical trials. A subject can fail due to lack of efficacy or due to a toxic reaction. Successful subjects will have both a positive response and no toxic side effects. Thus, we seek to maximize the product of the nontoxicity and efficacy dose‐response curves. We are interested in sampling rules that perform well along several criteria, including the ethical criterion that, as often as possible, experimental subjects be treated at or close to the maximum in question. Statistically, we wish to identify the optimum dose with high probability at the close of the experiment. Here, we propose designs that combine new allocation policies, directed walks, with new smoothed shape‐constrained curve‐fitting techniques. These are compared with a variety of other curve‐fitting techniques and with up‐and‐down and equal allocation rules.
Inferences on the Common Mean of Several Normal Populations Based on the Generalized Variable Method
Authors: Krishnamoorthy K. , Lu Yong
Published: June 2003

Summary This article presents procedures for hypothesis testing and interval estimation of the common mean of several normal populations. The methods are based on the concepts of generalized p‐value and generalized confidence limit. The merits of the proposed methods are evaluated numerically and compared with those of the existing methods. Numerical studies show that the new procedures are accurate and perform better than the existing methods when the sample sizes are moderate and the number of populations is four or less. If the number of populations is five or more, then the generalized variable method performs much better than the existing methods regardless of the sample sizes. The generalized variable method and other existing methods are illustrated using two examples.
The Use of Score Tests for Inference on Variance Components
Authors: Verbeke Geert , Molenberghs Geert
Published: June 2003

SummaryWhenever inference for variance components is required, the choice between one‐sided and two‐sided tests is crucial. This choice is usually driven by whether or not negative variance components are permitted. For two‐sided tests, classical inferential procedures can be followed, based on likelihood ratios, score statistics, or Wald statistics. For one‐sided tests, however, one‐sided test statistics need to be developed, and their null distribution derived. While this has received considerable attention in the context of the likelihood ratio test, there appears to be much confusion about the related problem for the score test. The aim of this paper is to illustrate that classical (two‐sided) score test statistics, frequently advocated in practice, cannot be used in this context, but that well‐chosen one‐sided counterparts could be used instead. The relation with likelihood ratio tests will be established, and all results are illustrated in an analysis of continuous longitudinal data using linear mixed models.
Generalized Semiparametrically Structured Ordinal Models
Authors: Tutz Gerhard
Published: June 2003

SummarySemiparametrically structured models are defined as a class of models for which the predictors may contain parametric parts, additive parts of covariates with an unspecified functional form, and interactions which are described as varying coefficients. In the case of an ordinal response the complexity of the predictor is determined by different sorts of effects. Global effects and category‐specific effects are distinguished; the latter allow the effect to vary across response categories. A general framework is developed in which global as well as category‐specific effects may have unspecified functional form. The framework extends various existing methods of modeling ordinal responses. The Wilkinson‐Rogers notation is extended to incorporate smooth model parts and varying coefficient terms, the latter being important for the smooth specification of category‐specific effects.
The Intensity‐Score Approach to Adjusting for Confounding
Authors: Brumback Babette , Greenland Sander , Redman Mary , Kiviat Nancy , Diehr Paula
Published: June 2003

SummaryIn a recent article on the efficacy of antihypertensive therapy,Berlowitz et al.(1998,New England Journal of Medicine339,1957–1963) introduced anad hocmethod of adjusting for serial confounding assessed via an intensity score, which records cumulative differences over time between therapy actually received and therapy predicted by prior medical history. Outcomes are subsequently regressed on the intensity score and baseline covariates to determine whether intense treatment or exposure predicts a favorable response. We use a structural nested mean model to derive conditions sufficient for interpreting the Berlowitz results causally. We also consider a modified approach that scales the intensity at each time by the inverse expected treatment given prior medical history. This leads to a simple, two‐step implementation of G‐estimation if we assume a nonstandard but useful structural nested mean model in which subjects less likely to receive treatment are more likely to benefit from it. These modeling assumptions apply, for example, to health services research contexts in which differential access to care is a primary concern. They are also plausible in our analysis of the causal effect of potent antiretroviral therapy on change in CD4 cell count, because men in the sample who are less likely to initiate treatment when baseline CD4 counts are high are more likely to experience large positive changes. We further extend the methods to accomodate repeated outcomes and time‐varying effects of time‐varying exposures.
Bayesian Latent Variable Models for Median Regression on Multiple Outcomes
Authors: B. Dunson David , Watson M. , Taylor Jack A.
Published: June 2003

SummaryOften a response of interest cannot be measured directly and it is necessary to rely on multiple surrogates, which can be assumed to be conditionally independent given the latent response and observed covariates. Latent response models typically assume that residual densities are Gaussian. This article proposes a Bayesian median regression modeling approach, which avoids parametric assumptions about residual densities by relying on an approximation based on quantiles. To accommodate within‐subject dependency, the quantile response categories of the surrogate outcomes are related to underlying normal variables, which depend on a latent normal response. This underlying Gaussian covariance structure simplifies interpretation and model fitting, without restricting the marginal densities of the surrogate outcomes. A Markov chain Monte Carlo algorithm is proposed for posterior computation, and the methods are applied to single‐cell electrophoresis (comet assay) data from a genetic toxicology study.
On the Precision of the Conditionally Autoregressive Prior in Spatial Models
Authors: Hodges James S. , Carlin Bradley P. , Fan Qiao
Published: June 2003

SummaryBayesian analyses of spatial data often use a conditionally autoregressive (CAR) prior, which can be written as the kernel of an improper density that depends on a precision parameter τ that is typically unknown. To include τ in the Bayesian analysis, the kernel must be multiplied byτkfor somek. This article rigorously derivesk= (n−I)/2for theL2norm CAR prior (also called a Gaussian Markov random field model) andk=n−Ifor theL1norm CAR prior, wherenis the number of regions andIthe number of “islands” (disconnected groups of regions) in the spatial map. SinceI= 1for a spatial structure defining a connected graph, this supportsKnorr‐Held's(2002, inHighly Structured Stochastic Systems, 260–264) suggestion thatk= (n− 1)/2in theL2norm case, instead of the more commonk=n/2. We illustrate the practical significance of our results using a periodontal example.
A Tree‐Based Scan Statistic for Database Disease Surveillance
Authors: Kulldorff Martin , Fang Zixing , Walsh Stephen J
Published: June 2003

SummaryMany databases exist with which it is possible to study the relationship between health events and various potential risk factors. Among these databases, some have variables that naturally form a hierarchical tree structure, such as pharmaceutical drugs and occupations. It is of great interest to use such databases for surveillance purposes in order to detect unsuspected relationships to disease risk. We propose a tree‐based scan statistic, by which the surveillance can be conducted with a minimum of prior assumptions about the group of occupations/drugs that increase risk, and which adjusts for the multiple testing inherent in the many potential combinations. The method is illustrated using data from the National Center for Health Statistics Multiple Cause of Death Database, looking at the relationship between occupation and death from silicosis.
Persistence and Heterogeneity in Habitat Selection Studies Using Radio Telemetry
Authors: Ramsey Fred L. , Usner Dale
Published: June 2003

Summary Biologists attach radio transmitters to animals so that the animals' movements through their preferred habitats can be followed. To analyze the resulting sequences of visited habitat classes, McCracken, Manly, and Vander Heyden (1998, Journal of Agricultural, Biological, and Environmental Statistics3(3), 268–279) proposed an independent multinomial selections (IMS) model. Two issues that arise when using this approach are: (i) serial dependence possibly affects measures of uncertainty; and (ii) individual animals from the population studied may exhibit heterogeneity in their selection patterns. We develop two single‐parameter extensions of the IMS model to address these issues. A Markov chain model allows for persistence in the habitat class previously visited. Heterogeneity is modeled by assuming the population of animal selection patterns follows a Dirichlet distribution, from which the study animals are a random sample. We show that these persistence and heterogeneity characteristics are present in the study by McCracken et al. (1998) of bear movements. Simulations demonstrate that failure to account for persistence or heterogeneity when either is present can seriously misrepresent measures of uncertainty.
Autoregressive Models for Capture‐Recapture Data: A Bayesian Approach
Authors: Johnson Devin S. , Hoeting Jennifer A.
Published: June 2003

Summary In this article, we incorporate an autoregressive time‐series framework into models for animal survival using capture‐recapture data. Researchers modeling animal survival probabilities as the realization of a random process have typically considered survival to be independent from one time period to the next. This may not be realistic for some populations. Using a Gibbs sampling approach, we can estimate covariate coefficients and autoregressive parameters for survival models. The procedure is illustrated with a waterfowl band recovery dataset for northern pintails (Anas acuta). The analysis shows that the second lag autoregressive coefficient is significantly less than 0, suggesting that there is a triennial relationship between survival probabilities and emphasizing that modeling survival rates as independent random variables may be unrealistic in some cases. Software to implement the methodology is available at no charge on the Internet.
Estimation of the Size of an Open Population Using Local Estimating Equations II: A Partially Parametric Approach
Authors: Yang Hsin‐Chou , Huggins Richard , Clark Austina S. S.
Published: June 2003

Summary Kernel smoothing methods are applied to extend a modification of the closed population approach of Lloyd and Yip (1991, in Estimating Equations, 65–88) to open populations with frequent capture occasions. The method complements previous nonparametric methods and, when the parametric assumptions are met, simulations show the new method has a smaller integrated mean squared error than the previous fully nonparametric method. The method is applied to capture‐recapture data on short‐tailed shearwaters collected annually for 48 years.
Decision‐Theoretic Designs for Phase II Clinical Trials Allowing for Competing Studies
Authors: Stallard Nigel
Published: June 2003

Summary This article describes an approach to optimal design of phase II clinical trials using Bayesian decision theory. The method proposed extends that suggested by Stallard (1998, Biometrics54, 279–294) in which designs were obtained to maximize a gain function including the cost of drug development and the benefit from a successful therapy. Here, the approach is extended by the consideration of other potential therapies, the development of which is competing for the same limited resources. The resulting optimal designs are shown to have frequentist properties much more similar to those traditionally used in phase II trials.
Multiple Outputation: Inference for Complex Clustered Data by Averaging Analyses from Independent Data
Authors: Follmann Dean , Proschan Michael , Leifer Eric
Published: June 2003

Summary This article applies a simple method for settings where one has clustered data, but statistical methods are only available for independent data. We assume the statistical method provides us with a normally distributed estimate, , and an estimate of its variance . We randomly select a data point from each cluster and apply our statistical method to this independent data. We repeat this multiple times, and use the average of the associated as our estimate. An estimate of the variance is given by the average of the minus the sample variance of the . We call this procedure multiple outputation, as all “excess” data within each cluster is thrown out multiple times. Hoffman, Sen, and Weinberg (2001, Biometrika88, 1121–1134) introduced this approach for generalized linear models when the cluster size is related to outcome. In this article, we demonstrate the broad applicability of the approach. Applications to angular data, p‐values, vector parameters, Bayesian inference, genetics data, and random cluster sizes are discussed. In addition, asymptotic normality of estimates based on all possible outputations, as well as a finite number of outputations, is proven given weak conditions. Multiple outputation provides a simple and broadly applicable method for analyzing clustered data. It is especially suited to settings where methods for clustered data are impractical, but can also be applied generally as a quick and simple tool.
A Cautionary Note on Exact Unconditional Inference for a Difference between Two Independent Binomial Proportions
Authors: Mehrotra Devan V. , Chan Ivan S. F. , Berger Roger L.
Published: June 2003

SummaryFisher's exact test for comparing response proportions in a randomized experiment can be overly conservative when the group sizes are small or when the response proportions are close to zero or one. This is primarily because the null distribution of the test statistic becomes too discrete, a partial consequence of the inference beingconditionalon the total number of responders. Accordingly, exactunconditionalprocedures have gained in popularity, on the premise that power will increase because the null distribution of the test statistic will presumably be less discrete. However, we caution researchers that a poor choice of test statistic for exact unconditional inference can actually result in a substantially less powerful analysis than Fisher's conditional test. To illustrate, we study a real example and provide exact test size and power results for several competing tests, for both balanced and unbalanced designs. Our results reveal that Fisher's test generally outperforms exact unconditional tests based on using as the test statistic either the observed difference in proportions, or the observed difference divided by its estimated standard error under the alternative hypothesis, the latter for unbalanced designs only. On the other hand, the exact unconditional test based on the observed difference divided by its estimated standard error under the null hypothesis (score statistic) outperforms Fisher's test, and is recommended. Boschloo's test, in which the p‐value from Fisher's test is used as the test statistic in an exact unconditional test, is uniformly more powerful than Fisher's test, and is also recommended.
UCP3 Protein Regulation in Human Skeletal Muscle Fibre Types I, IIa and IIx is Dependent on Exercise Intensity
Authors: Russell Aaron P. , Somm Emmanuel , Praz Manu , Crettenand Antoinette , Hartley Oliver , Melotti Astrid , Giacobino Jean‐Paul , Muzzin Patrick , Gobelet Charles , Dériaz Olivier
Published: June 2003

It has been proposed that mitochondrial uncoupling protein 3 (UCP3) behaves as an uncoupler of oxidative phosphorylation. In a cross‐sectional study, UCP3 protein levels were found to be lower in all fibre types of endurance‐trained cyclists as compared to healthy controls. This decrease was greatest in the type I oxidative fibres, and it was hypothesised that this may be due to the preferential recruitment of these fibres during endurance training. To test this hypothesis, we compared the effects of 6 weeks of endurance (ETr) and sprint (STr) running training on UCP3 mRNA expression and fibre‐type protein content using real‐time PCR and immunofluorescence techniques, respectively. UCP3 mRNA and protein levels were downregulated similarly in ETr and STr (UCP3 mRNA: by 65 and 50 %, respectively; protein: by 30 and 27 %, respectively). ETr significantly reduced UCP3 protein content in type I, IIa and IIx muscle fibres by 54, 29 and 16 %, respectively. STr significantly reduced UCP3 protein content in type I, IIa and IIx muscle fibres by 24, 31 and 26 %, respectively. The fibre‐type reductions in UCP3 due to ETr, but not STr, were significantly different from each other, with the effect being greater in type I than in type IIa, and in type IIa than in type IIx fibres. As a result, compared to STr, ETr reduced UCP3 expression significantly more in fibre type I and significantly less in fibre types IIx. This suggests that the more a fibre is recruited, the more it adapts to training by a decrease in its UCP3 expression. In addition, the more a fibre type depends on fatty acid β oxidation and oxidative phosphorylation, the more it responds to ETr by a decrease in its UCP3 content.
Area 21a of cat visual cortex strongly modulates neuronal activities in the superior colliculus
Authors: Hashemi‐Nezhad M. , Wang C. , Burke W. , Dreher B.
Published: June 2003

We have examined the influence of cortico‐tectal projections from one of the pattern‐processing extrastriate visual cortical areas, area 21a, on the responses to visual stimuli of single neurones in the superior colliculi of adult cats. For this purpose area 21a was briefly inactivated by cooling to 10 °C using a Peltier device. Responses to visual stimuli before and during cooling as well as after rewarming ipsilateral area 21a were compared. In addition, in a subpopulation of collicular neurones we have studied the effects of reversible inactivation of ipsilateral striate cortex (area 17, area V1). When area 21a was cooled, the temperature of area 17 was kept at 36 °C and vice versa. In the majority of cases (41/65; 63 %), irrespective of the velocity response profiles of collicular neurones, inactivation of area 21a resulted in a significant decrease in magnitude of responses of neurones in the ipsilateral colliculus and only in a small proportion of cells (2/65; 3.1 %) was there a significant increase in the magnitude of responses. Inactivation of area 21a resulted in significant changes in the magnitude of responses of collicular cells located not only in the retino‐recipient layers but also in the stratum griseum intermediale. In most cases, reversible inactivation of area 17 resulted in a greater reduction in the magnitude of responses of collicular cells than inactivation of area 21a. Reversible inactivation of area 21a also affected the direction selectivity indices and length tuning of most collicular cells tested.
Interstitial cells: involvement in rhythmicity and neural control of gut smooth muscle
Authors: Hirst G. D. S. , Ward S. M.
Published: June 2003

Many smooth muscles display spontaneous electrical and mechanical activity, which persists in the absence of any stimulation. In the past this has been attributed largely to the properties of the smooth muscle cells. Now it appears that in several organs, particularly in the gastrointestinal tract, activity in smooth muscles arises from a separate group of cells, known as interstitial cells of Cajal (ICC), which are distributed amongst the smooth muscle cells. Thus in the gastrointestinal tract, a network of interstitial cells, usually located near the myenteric plexus, generates pacemaker potentials that are conducted passively into the adjacent muscle layers where they produce rhythmical membrane potential changes. The mechanical activity of most smooth muscle cells, can be altered by autonomic, or enteric, nerves innervating them. Previously it was thought that neuroeffector transmission occurred simply because neurally released transmitters acted on smooth muscle cells. However, in several, but not all, regions of the gastrointestinal tract, it appears that nerve terminals, rather than communicating directly with smooth muscle cells, preferentially form synapses with ICC and these relay information to neighbouring smooth muscle cells. Thus a set of ICC, which are distributed amongst the smooth muscle cells of the gut, are the targets of transmitters released by intrinsic enteric excitatory and inhibitory nerve terminals: in some regions of the gastrointestinal tract, the same set of ICC also augment the waves of depolarisation generated by pacemaker ICC. Similarly in the urethra, ICC, distributed amongst the smooth muscle cells, generate rhythmic activity and also appear to be the targets of autonomic nerve terminals.
Metal resistance among aerobic chemoheterotrophic bacteria from the deep terrestrial subsurface
Authors: Benyehuda G , Coombs J , Ward P L , Balkwill D , Barkay T
Published: June 2003

The metal resistance of 350 subsurface bacterial strains from two U.S. Department of Energy facilities, the Savannah River Site (SRS), South Carolina, and the Hanford site, Washington, was determined to assess the effect of metal toxicity on microorganisms in the deep terrestrial subsurface. Resistance was measured by growth inhibition around discs containing optimized amounts of Hg(II), Pb(II), and Cr(VI). A broad range of resistance levels was observed, with some strains of Arthrobacter spp. demonstrating exceptional tolerance. A higher level of resistance to Hg(II) and Pb(II) (P < 0.05) and a higher occurrence of multiple resistances suggested that metals more effectively influenced microbial evolution in subsurface sediments of the SRS than in those of the Hanford site. Common resistance to heavy metals suggests that toxic metals are unlikely to inhibit bioremediation in deep subsurface environments that are contaminated with mixed wastes.Key words: deep subsurface, metal resistance, mercury, chromium, lead.
Multidrug resistant phenotype of Bacillus subtilis spontaneous mutants isolated in the presence of puromycin and lincomycin
Authors: Murata Makiko , Ohno Shinichi , Kumano Miyuki , Yamane Kunio , Ohki Reiko
Published: June 2003

Spontaneous mutants were isolated by growing Bacillus subtilis 168 in the presence of high concentrations of puromycin and lincomycin. These mutants showed increased resistance to several drugs other than these two drugs. The lmrAB genes, which encode a transcriptional repressor and a drug efflux protein of the major facilitator superfamily, were involved in this phenotype. Northern hybridization analysis showed that the expression of lmrAB gene increased more than 30-fold. The following two types of mutations were found to be responsible for the multidrug resistant phenotype: (i) a nucleotide replacement in the region between the promoter and initiation codon of lmrA and (ii) nucleotide replacements that resulted in amino acid replacements in the LmrA protein. The results indicate that LmrB is a multidrug resistant protein and that LmrA is a repressor, which autogenously represses the transcription of the lmrAB operon.Key words: multidrug resistance (MDR), major facilitator superfamily (MFS), lincomycin resistance, lmrAB genes.
Melanin biosynthesis in the fungusCurvularia lunata(teleomorph:Cochliobolus lunatus)
Authors: Rižner Tea Lanisnik , Wheeler Michael H
Published: June 2003

Curvularia lunata (teleomorph: Cochliobolus lunatus) is a known plant and human pathogen. Tricyclazole, a specific inhibitor of pentaketide melanin biosynthesis, blocked the biosynthesis of melanin in Curvularia lunata and caused the accumulation of the melanin metabolites flaviolin and 2-hydroxyjuglone. This showed that melanin in Curvularia lunata is produced by a pentaketide pathway from 1,8-dihydroxynaphthalene. The 1,3,8-trihydroxynaphthalene reductase (3HNR) gene, associated with the melanin pathway of Curvularia lunata, was identified and characterized. An alignment of 3HNR sequences enabled the design of primers covering conserved regions. A PCR-amplified fragment of Curvularia lunata genomic DNA was used for screening the cDNA library. Three independent cDNA clones revealed an 801-bp open reading frame encoding a 267 amino acid protein. The protein was expressed in Escherichia coli and purified to homogeneity. The predicted amino acid sequence of the 28.6-kDa protein demonstrated homology to other fungal 3HNR and other members of the short-chain dehydrogenase super family. Northern analyses revealed that 3HNR from Curvularia lunata is expressed synchronously with melanization after 3 days of Curvularia lunata growth in malt extract medium. No 3HNR reductase gene expression nor melanization was observed when Curvularia lunata was grown in yeast nitrogen base medium.Key words: melanin, fungi, Curvularia lunata, Cochliobolus lunatus, trihydroxynaphthalene reductase.
Algicidal activity and gliding motility of Saprospira sp. SS98-5
Authors: Furusawa Gou , Yoshikawa Takeshi , Yasuda Akihiro , Sakata Taizo
Published: June 2003

A marine bacterium, Saprospira sp. SS98-5, which was isolated from Kagoshima Bay, Japan, was able to kill and lyse the cells of the diatom Chaetoceros ceratosporum. The multicellular filamentous cells of this bacterium captured the diatom cells, formed cell aggregates, and lysed them in an enriched sea water (ESS) liquid medium. Strain SS98-5 also formed plaques on double layer agar plates incorporating diatom cells. The diatom cell walls were partially degraded at the contact sites with the bacteria, the bacteria invaded from there into the diatom cells, and then the diatom cells were completely lysed. The strain possessed gliding motility and grew as spreading colonies on ESS agar plates containing lower concentrations of polypeptone (below 0.1%) while forming nonspreading colonies on ESS agar plates containing 0.5% polypeptone. Electron micrographs of ultrathin sections demonstrated that microtubule-like structures were observable only in gliding motile cells. Both the gliding motility and the microtubule-like structures were diminished by the addition of podophyllotoxin, an inhibitor of microtubule assembly, suggesting that the microtubule-like structures observed in these bacterial cells are related to their gliding motility.Key words: Saprospira sp., Chaetoceros ceratosporum, gliding motility, algicidal activity, microtubule-like structure.
Germination and adhesion of fungal conidia on polycarbonate membranes and on apple fruit exposed to mycoactive acetate esters
Authors: Filonow Alexander B
Published: June 2003

The adhesion and germination of conidia of nine fungal species were assessed on polycarbonate membranes or on the skin of apple fruit in sealed glass bottles injected or not injected with acetate esters. Adhesion was determined after dislodging conidia from surfaces using a sonication probe. Adhesion and germination of conidia of Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Penicillium citrinum, Penicillium claviforme, or Trichoderma sp. on membranes after 48 h were not increased in a 1.84 μg mL1headspace of butyl acetate (BA), ethyl acetate, hexyl acetate, 2-methylbutyl acetate, pentyl acetate, or propyl acetate. Adhesion and germination of Botrytis cinerea, Penicillium expansum, and Penicillium roquefortii conidia were stimulated by all esters. Only conidia of B. cinerea and P. expansum exhibited increased adhesion and germination on the skin of apple fruit in bottles exposed to 0.92 μg mL1of BA. Only conidia of B. cinerea and P. expansum produced decay in inoculated puncture wounds on fruit. Freshly made puncture wounds or 24-h-old puncture wounds in fruit were more adhesive than the unpunctured skin of fruit to conidia of B. cinerea or P. expansum. Fresh wounds were more adhesive to both fungi than 24-h-old puncture wounds. The skin and wounds of fruit were as adhesive to B. cinerea conidia as they were to P. expansum conidia. A 4-h exposure to 1.43 μg mL1of BA increased adhesion of B. cinerea and P. expansum conidia in 24-h-old wounds. Results suggest that acetateester stimulation most likely is not a rare phenomenon in the fungi. For nutrient-dependent decay pathogens of apple fruit, acetate esters may be an alternative chemical cue used to maintain adhesion of conidia to wound surfaces.Key words: spore adhesion, spore germination, mycoactive compounds.
Bacteriophage λ repressor allelic modulation of the Rex exclusion phenotype
Authors: Slavcev Roderick A , Bull Harold J , Hayes Sidney
Published: June 2003

The sensitivity of Δred-gamΔren mutants of bacteriophage λ to Rex exclusion by λrexA+rexB+lysogens is modulated by the prophage cI repressor allele. We show the following: (i) λspi156Δnin5 forms plaques on a cI+rexA+rexB+lysogen with 105-fold higher efficiency than on cI[Ts]rexA+rexB+derivatives. (ii) The cI[Ts]857 allele augmentation of Rex exclusion is recessive to cI+. (iii) The cI857-mediated increase in Rex exclusion activity involves the participation of a genetic element mapping outside of cIrexArexB. Key words: bacteriophage lambda (λ), CI repressor, Rex exclusion phenotype, cIrexArexB operon, bacteriophage λspi156Δnin5, cI[Ts]857, cI[Ts]2.
Biodegradation of cyclic amines by aPseudomonasstrain involves an amine mono-oxygenase
Authors: Trigui M , Pulvin S , Poupin P , Thomas D
Published: June 2003

Pseudomonas putida O1G3 catalyzes the degradation of pyrrolidine and piperidine. This strain can use these compounds as the sole source of carbon, nitrogen, and energy. When the cyclic amines were used as the growth substrates, the synthesis of a soluble heme amine mono-oxygenase was induced in this bacteria. This observation was confirmed by spectrophotometric analysis and specific inhibitor. This mono-oxygenase is a NADH-dependent enzyme and catalyzes the cleavage of the CN bond of the pyrrolidine and piperidine ring by a mechanism similar to a N dealkylation. This reaction could be followed by ring cleavage to form γ-aminobutyraldehyde oxidized to γ-aminobutyrate. Further investigations to purify the heme-containing mono-oxygenase are in progress.Key words: biodegradation, Pseudomonas, pyrrolidine, piperidine, amine mono-oxygenase.
Immunodetection of spectrin-like proteins in yeasts
Authors: Slaninová Iva , Holubárová Alena , Svoboda Augustin
Published: June 2003

Spectrin, a component of the membrane skeleton in erythrocytes and other animal cells, has also been identified in plant and fungal cells. However, its postulated role, i.e., the maintenance of shape and elasticity of the plasma membrane, is probably not exerted in walled cells. To study spectrin in these cells, we chose yeasts because of a high morphological variability of their life cycle. The localization of spectrin in the cells and protoplasts of Saccharomyces cerevisiae and Schizosaccharomyces japonicus var. versatilis was detected by immunoblotting, indirect immunofluorescence, and immunogold electron microscopy techniques with the use of anti-chicken and anti-human erythrocyte spectrin antibodies. A protein band of 220240 kDa and some bands of lower relative mass were detected in cell and protoplast extracts of both yeast strains. Spectrin-like proteins were revealed by fluorescence microscopy at cell surfaces and in vacuolar membranes. Immunogold-labelling showed spectrin-like proteins in the plasma membrane, endoplasmic reticulum, vacuoles, nuclei, vesicles, mitochondria, and cell walls. The topology of spectrin was not affected by actin depolymerization with Latrunculin B nor was it changed in either act1-1 or cdc42 mutants, under restrictive conditions. Under osmotic stress, both spectrin and actin were delocalized and appeared in the form of large clusters in the cytoplasm. It is concluded that a protein cross-reacting with spectrin antibodies is present in fission and budding yeasts. Generally, it is located in the proximity of the plasma membrane and other intracellular membranes, probably as a part of the membrane skeleton. No evidence of its relationship to either actin or growth zones of the cell can be provided.Key words: actin, membrane skeleton, Saccharomyces, Schizosaccharomyces, spectrin, yeast.