bluuebunny/crossref_metadata_2025 huggingface dataset:
Increasing Retention Without Increasing Study Time
Authors: Rohrer Doug , Pashler Harold
Published: August 2007

Because people forget much of what they learn, students could benefit from learning strategies that yield long-lasting knowledge. Yet surprisingly little is known about how long-term retention is most efficiently achieved. Here we examine how retention is affected by two variables: the duration of a study session and the temporal distribution of study time across multiple sessions. Our results suggest that a single session devoted to the study of some material should continue long enough to ensure that mastery is achieved but that immediate further study of the same material is an inefficient use of time. Our data also show that the benefit of distributing a fixed amount of study time across two study sessions—the spacing effect—depends jointly on the interval between study sessions and the interval between study and test. We discuss the practical implications of both findings, especially in regard to mathematics learning.
Democratic Deliberation as the Open‐Ended Construction of Justice
Authors: RUMMENS STEFAN
Published: August 2007

Abstract. An analysis of the epistemological structure of democratic deliberation as a procedure in which legal norms are constructed reveals that deliberation combines procedural and substantive aspects in a unique and inextricable manner. The co‐original recognition of the private and public autonomy of all citizens provides the substantive critical standard against which the justice of norms is measured. At the same time, such recognition requires that the particular needs and values of all people concerned be taken into account. Given the privileged epistemic access people have to their own particular perspective, this requirement implies the ineliminability of actual deliberative procedures. The open‐ended nature of these constructive procedures is partly due to the fact that the rules of the procedure are counterfactual and themselves subject to interpretation. More importantly, it also reflects the historical nature of our human world and the freedom of moral persons to shape and reshape their preferences.
The Deliberative Model of Democracy: Two Critical Remarks
Authors: GEENENS RAF
Published: August 2007

Abstract.  The deliberative model of democracy, as presented by Jürgen Habermas and others, claims to reconstruct the normative content of the idea of democracy. However, since it overemphasises the epistemic facet of decision‐making, the model is unable to take into account other valuable aspects of democracy. This is shown in reference to two concrete phenomena from political reality: majority voting and the problem of the dissenter. In each case, the deliberative model inevitably fails to account for several normatively desirable features of democracy, such as formal political equality and proper respect for the judgement of each citizen.
Green Constitutionalism: The Constitutional Protection of Future Generations
Authors: EKELI KRISTIAN SKAGEN
Published: August 2007

Abstract.  The purpose of this paper is to propose and consider a new constitutional provision that can contribute to the protection of the vital needs of future generations. The proposal I wish to elaborate can be termed the posterity provision, and it has both substantive and procedural elements. The aim of this constitutional provision is twofold. The first is to encourage state authorities to make more future‐oriented deliberations and decisions. The second is to create more public awareness and improve the process of public deliberation about issues affecting near and remote future generations. It is argued that a good case can be made for the proposed reforms compared with alternative substantive constitutional environmental provisions found in existing constitutions and in the literature on legal and political theory. The main reason for this is that the proposed law constitutes a better and more adequate basis for judicial enforcement than the alternatives, which tend to be very vague or unclear. In this connection, I contend that there are both epistemological and moral reasons for introducing constitutional provisions that focus on the protection of critical natural resources essential for meeting the basic physiological needs of future people. It is also argued that the posterity provision can be defended on the basis of central ideas and ideals in recent theory of deliberative democracy.
Imitation, interaction and dialogue using Intensive Interaction: tea party rules
Authors: BARBER MARK
Published: August 2007

Intensive Interaction has become widely used when building up communication with children with profound learning difficulties. Often practitioners understand Intensive Interaction to be primarily about imitation and Mark Barber shows how this can be a misunderstanding that limits the kinds of interactions that can be enjoyed by conversation partners. The article explores how instead of just imitating, practitioners need to develop (wordless) conversations so they can follow the child's lead, introduce their own closely related ideas, provide variations and generally keep to the ‘tea‐party rules’ developed by typically developing young children at play.
Assessing and teaching children at the early stages of development. Combining psychology and ICT: an evaluation of a short inservice course for teachers of pupils with PMLD
Authors: WARE JEAN , THORPE PETER
Published: August 2007

This paper reports findings from a follow‐up evaluation of a short inservice course designed to enable teachers to assess and teach pupils with PMLD more effectively by combining the use of custom built ICT hardware and software (the Declan materials) and cognitive developmental psychology. The Declan materials were introduced to teachers at a short inservice course and all participants completed an evaluation form at the end of the course. Twelve months later participants took part in a telephone interview. Just under half of those interviewed were using the materials with pupils and were very positive about the impact of the materials on pupil progress. Those not using the materials were still positive about the course, but reported a number of barriers to use of the materials, including lack of confidence in setting up the hardware and software, lack of other resources, and classroom organizational issues.
Special school reorganization by a local unitary authority: some lessons learned
Authors: ASHDOWN ROB , DARLINGTON CHRIS
Published: August 2007

This paper reports on the process and outcomes of special school reorganization in one local authority with a particular emphasis upon the implications for those concerned with the education of children with profound and multiple learning difficulties (PMLD). The authors believe that reporting this experience provides pointers for others considering or undergoing special school reorganization. Emphasis is given to the importance of co‐operative teams and partnerships with professionals from different disciplines and with parents.
Remark: Putting Phases in Perspective
Authors: Boeckx Cedric , Grohmann Kleanthes K.
Published: August 2007

Abstract. We offer here some remarks on the concept of phases, as formulated in recent developments on minimalist theorizing. Our main objective is to express our feeling that, in their present definitions, phases are poorly understood. We argue that the major properties of phases can be viewed as reincarnations of explanations in terms of islands (or bounding nodes and successive cyclicity, respectively). The present remarks are intended as productive stimulation to home in on a better conceptualization of the notion “phase” and what issues might arise under current theoretical considerations.
The Derivation of Clausal Gerunds
Authors: Pires Acrisio
Published: August 2007

Abstract. This paper investigates the syntax of clausal gerunds—a class of gerunds that can have either a null subject or an overt DP Case‐marked with accusative or nominative. First, it addresses the difficulty of accounting for gerunds that allow both null and overt subjects in principles and parameters/minimalist approaches to Case and control. Second, the paper explores the existence of a common structure for the two clausal gerunds, supported by the absence of empirical distinctions in their feature specification, especially regarding tense. Third, the paper introduces new observations about the distribution of clausal gerunds and argues that the complex alternations and restrictions on their distribution results from the interaction between Case and Agreement valuation, the limited possibility of A‐movement out of a clausal gerund, and convergence considerations resulting from the existence of distinct numerations.
Nested Generalized Linear Mixed Models: An Orthodox Best Linear Unbiased Predictor Approach
Authors: Ma Renjun , Jørgensen Bent
Published: August 2007

We introduce a new class of generalized linear mixed models based on the Tweedie exponential dispersion model distributions, accommodating a wide range of discrete, continuous and mixed data. Using the best linear unbiased predictor of random effects, we obtain an optimal estimating function for the regression parameters in the sense of Godambe, allowing an efficient common fitting algorithm for the whole class. Although allowing full parametric inference, our main results depend only on the first- and second-moment assumptions of unobserved random effects. In addition, we obtain consistent estimators for both regression and dispersion parameters. We illustrate the method by analysing the epilepsy data and cake baking data. Along with simulations and asymptotic justifications, this shows the usefulness of the method for analysis of clustered non-normal data.
Statistical Inference for Evolving Periodic Functions
Authors: Genton Marc G. , Hall Peter
Published: August 2007

In the study of variable stars, where the light reaching an observer fluctuates over time, it can be difficult to explain the nature of the variation unless it follows a regular pattern. In this respect, so-called periodic variable stars are particularly amenable to analysis. There, radiation varies in a perfectly periodic fashion, and period length is a major focus of interest. We develop methods for conducting inference about features that might account for departures from strict periodicity. These include variation, over time, of the period or amplitude of radiation. We suggest methods for estimating the parameters of this evolution, and for testing the hypothesis that the evolution is present. This problem has some unusual features, including subtle issues of identifiability.
L1-Regularization Path Algorithm for Generalized Linear Models
Authors: Park Mee Young , Hastie Trevor
Published: August 2007

We introduce a path following algorithm for L1-regularized generalized linear models. The L1-regularization procedure is useful especially because it, in effect, selects variables according to the amount of penalization on the L1-norm of the coefficients, in a manner that is less greedy than forward selection–backward deletion. The generalized linear model path algorithm efficiently computes solutions along the entire regularization path by using the predictor–corrector method of convex optimization. Selecting the step length of the regularization parameter is critical in controlling the overall accuracy of the paths; we suggest intuitive and flexible strategies for choosing appropriate values. We demonstrate the implementation with several simulated and real data sets.
Does Metoprolol Inhibit the Cortical Spreading Depression? Acute Effects of Systematic Metropol on CSD in Rats
Authors: Alemdar M , Akman Ö , Selekler HM , Komsuoğlu SŞ , Ateş N
Published: August 2007

Cortical spreading depression (CSD) is supposed to be the underlying biological basis of the migraine aura. Metoprolol was proven to be effective in migraine prophylaxis in clinical trials, but its mechanism of action has not been clarified yet. We studied direct effects of metoprolol on a continuous CSD induction model in rats. Six adult Wistar rats were anaesthetized with intraperitoneal thiopental (50 mg/kg). CSD was induced with application of 1 M KCL through a burr hole into the left frontal dura-mater, and recorded by an Ag/AgCl DC electrode on the left parietal dura-mater. After a basal recording of CSD induction during the first 40-min period, metoprolol (5 mg/kg) was infused within 4 min. Then DC recordings were maintained for a further 120 min. Any significant differences in total number and duration of CSDs before and after metoprolol administration were not detected. This study suggests that the mode of action of metoprolol in prophylaxis is not via direct CSD inhibition.
Symptoms of Cutaneous Sensitivity Pre-Treatment and Post-Treatment: Results from the Rizatriptan TAME Studies
Authors: Cady R , Martin V , Mauskop A , Rodgers A , Hustad CM , Ramsey KE , Skobieranda F
Published: August 2007

The presence of cutaneous allodynia may predict response to triptans. Identical randomized double-blind studies were conducted comparing the efficacy of rizatriptan 10 mg or placebo administered within 1 h of headache onset, while pain was mild. The primary endpoint was freedom from pain at 2 h. Presence of symptoms suggesting cutaneous sensitivity (SCS) at baseline and at 2 h post-treatment was recorded. Before treatment, 29% of rizatriptan patients and 22% of placebo patients reported SCS. At 2 h, the percentage of patients with SCS was significantly decreased with rizatriptan. The presence of SCS pre-treatment was not predictive of response to rizatriptan. Most patients with SCS at 2 h were non-responders. Early treatment with rizatriptan significantly reduced the percentage of patients with SCS at 2 h. The presence of SCS at baseline did not predict pain-free response, but presence of SCS at 2 h correlated with lack of a 2-h pain-free response.
The comparison of Nail Psoriasis Severity Index with a less time‐consuming qualitative system
Authors: Kaçar N , Ergin Ş , Erdoǧan BŞ
Published: August 2007

Objective  Reliable assessment of severity in nail psoriasis is essential to document treatment responses in clinical trials and routine clinical usage. In this study the correlation between Nail Psoriasis Severity Index (NAPSI) and Cannavo's scoring system was assessed, and inter‐rater correlation of NAPSI scores were evaluated.

Materials and Methods  Forty‐five patients with nail psoriasis were included. Target nails were selected and graded by the first dermatologist with both scoring systems. The nails were reevaluated by the second dermatologist with NAPSI.

Results  The two systems were highly correlated (P < 0.001). For NAPSI inter‐rater correlation was also significant (P < 0.001).

Conclusion  Our results showed that the qualitative and quantitative evaluations of the same rater were similar. Although the qualitative scoring system of Cannavo's is less time consuming than NAPSI, to suggest this system inter‐rater correlations should be evaluated.
An experimental study of translocation success and habitat improvement in wild rabbits
Authors: Cabezas S. , Moreno S.
Published: August 2007

The translocation of wild animals is a strategy frequently used in the conservation and management of natural populations. The aim of this study was to evaluate the impact of translocation (population supplementation) and habitat improvement on the abundance of European wild rabbitOryctolagus cuniculus. We used eight open plots with different habitat treatments: two with increased shelter, two with increased food, two with increased shelter and food and two without habitat treatment (control plots). We translocated wild rabbits during 3 consecutive years, each year in four of the eight plots, with the remaining plots serving as control for the translocation treatment. Rabbit abundance (translocated plus native rabbits) was calculated by means of pellet counts, and the results were evaluated mainly by generalized linear mixed models. We found that rabbit abundance was determined primarily by habitat improvement. Rabbits were more abundant in treated than in control plots, and most abundant in the plots where food availability was increased. This effect persisted throughout the year. Translocation also increased abundance, but this effect was the strongest where shelter and food had also been improved and declined and disappeared after breeding. These findings suggest that the habitat is an important factor for rabbit abundance, with food availability being the prime factor regulating densities. Moreover, translocations on their own are only effective in the short term in situations in which factors limiting population growth (e.g. disease and predation) have not been corrected. Translocations should be carried out in conjunction with improvements in release habitat as rabbit densities will depend on the maximum carrying capacity of the habitat.
Prioritizing the world's islands for vertebrate‐eradication programmes
Authors: Brooke M. de L. , Hilton G. M. , Martins T. L. F.
Published: August 2007

In the last 400 years, more species have become extinct on small islands than on continents. Yet, scant attention has hitherto been paid to prioritizing island restorations. Nevertheless, considerable conservation effort is now devoted to removing a major cause of these extinctions – invasive alien vertebrates. Because modern techniques allow the clearance of invasive vertebrates from quite large islands (up to 1000 km2), many islands are candidates for restoration. A robust strategy for allocating available funds is urgently needed. It requires, for each candidate island, an objective estimation of conservation gain and a method for predicting its financial cost. Our earlier work showed that a good first‐pass estimate of vertebrate eradication costs can be made using just island area and target species. Costs increase with island area, while rodents are more expensive per unit area than ungulates. Here, we develop a method for assessing the conservation benefit of a proposed eradication and apply the method to threatened birds, but not other taxa. The method, combining information on how threatened a species is, on the impact of alien vertebrates on that species and on the islands on which the species occurs, allows us to present a means of determining which islands yield the greatest conservation benefit per unit of expenditure on vertebrate eradication. In general, although greater overall benefit would accrue to birds from eradication of invasive vertebrates on larger islands, benefit per unit of expenditure is the highest on relatively small islands, and we identify those that should be priority targets for future eradications. Crucially, this quantitative assessment provides considerable efficiency gains over more opportunistic targeting of islands. The method could be adapted to prioritize islands on a regional or national basis, or with different conservation gains in mind.
Machado‐Joseph Disease Enhances Genetic Fitness: A Comparison Between Affected and Unaffected Women and Between MJD and the General Population
Authors: Prestes P. R. , Saraiva‐Pereira M. L. , Silveira I. , Sequeiros J. , Jardim L. B.
Published: August 2007

Background: Machado‐Joseph disease (MJD SCA3), a spinocerebellar ataxia related to expansion of a CAG tract, has already been related to anticipation and meiotic drift. However, fitness of MJD carriers has been little studied. Objective: To analyze genetic fitness of MJD patients, comparing them to their unaffected relatives and to the general population (GP) of origin. Subjects and methods: 182 informants, belonging to 82 MJD families, agreed to participate in the study. Informants supplied data about 828 MJD patients. Number of children (NC), gender, age, school attainment, menarche and menopause were compared between general and emeritus (older than 45 years of age or deceased) groups. Results: Mean NC of the GP and of MJD patients were respectively 1.90 and 2.93± 2.3 (p = 0.0037). Comparisons within families also showed differences: the mean NC of unaffected and affected emeritus MJD women were, respectively, 2.68 and 3.89 (p = 0.0037). Affected MJD women had earlier mean ages at the delivery of their first child and menopause (p < 0.011 and 0.07, respectively). Among affected women those who did not have children had larger CAG tracts than those who had children (p < 0.05). Conclusion: MJD enhances the fitness of its carriers, and this phenomenon seems to have a biological basis.
Adipose tissue at entheses: the innervation and cell composition of the retromalleolar fat pad associated with the rat Achilles tendon
Authors: Shaw H. M. , Santer R. M. , Watson A. H. D. , Benjamin M.
Published: August 2007

This study set out to determine whether the fat pad at the attachment of the Achilles tendon has features enabling it to function as an immune organ and a mechanosensory device, and to be a source of pain in insertional tendon injuries. Sections for histology and immunohistochemistry were cut from the Achilles tendon enthesis organ of 1 day old, 1 month, 4 month and 24 month old rats. For fluorescence and peroxidase immunohistochemistry, cryosections were labelled with primary antibodies directed against PGP9.5, substance P, neurofilament 200, calcitonin gene related peptide, CD68, CD36, myeloid related protein 14, actin and vinculin. The fat pad contained not only adipocytes, but also fibrous tissue, mast cells, macrophages, fibroblasts and occasional fibrocartilage cells. It was richly innervated with nerve fibres, some of which were likely to be nociceptive, and others mechanoreceptive (myelinated fibres, immunoreactive for neurofilament 200). The fibres lay between individual fat cells and in association with blood vessels. In marked contrast, the enthesis itself and all other components of the enthesis organ were aneural at all ages. The presence of putative mechanoreceptive and nociceptive nerve endings between individual fat cells supports the hypothesis that the fat pad has a proprioceptive role monitoring changes in the insertional angle of the Achilles tendon and that it may be a source of pain in tendon injuries. The abundance of macrophages suggests that the adipose tissue could have a role in combating infection and/or removing debris from the retrocalcaneal bursa.
Depressive symptoms among rural Bangladeshi mothers: implications for infant development
Authors: Black Maureen M. , Baqui Abdullah H. , Zaman K. , McNary Scot W. , Le Katherine , Arifeen Shams El , Hamadani Jena D. , Parveen Monowara , Yunus Md. , Black Robert E.
Published: August 2007

Objective:  To examine how maternal depressive symptoms are related to infant development among low‐income infants in rural Bangladesh and to examine how the relationship is affected by maternal perceptions of infant irritability and observations of caregiving practices.

Methods:  Development was measured among 221 infants at 6 and 12 months with the Bayley Scales II. Mothers reported on their depressive symptoms and on perceptions of their infant's temperament, and a home visit was made to complete the HOME Inventory.

Results:  Half (52%) the mothers reported depressive symptoms. In bivariate analyses, maternal depressive symptoms were related to low scores on the Bayley Scales. Infants whose mothers reported depressive symptoms and perceived their infants to be irritable acquired fewer cognitive, motor, and Orientation/Engagement skills between 6–12 months than infants whose mothers reported neither or only one condition. The relationship linking maternal depressive symptoms and perceived infant irritability with infant cognitive skills was partially mediated by parental responsiveness and opportunities for play in the home.

Conclusions:  The intergenerational risks of maternal depressive symptoms on infant development extend to rural Bangladesh and are accentuated when mothers perceive their infants as irritable. Mothers who report depressive symptoms and infant irritability may lack the capacity to provide responsive, developmentally‐oriented caregiving environments.
A spatially explicit analysis of seedling recruitment in the terrestrial orchid Orchis purpurea
Authors: Jacquemyn Hans , Brys Rein , Vandepitte Katrien , Honnay Olivier , Roldán‐Ruiz Isabel , Wiegand Thorsten
Published: August 2007

DOI: 10.1111/j.1469-8137.2007.02223.xCommentary p 237
Predicting the impact of changing CO2 on crop yields: some thoughts on food
Authors: Ziska Lewis H. , Bunce James A.
Published: August 2007

Recent breakthroughs in CO2 fumigation methods using free‐air CO2 enrichment (FACE) technology have prompted comparisons between FACE experiments and ‘enclosure studies’ with respect to quantification of the effects of projected atmospheric CO2 concentrations on crop yields. On the basis of one such comparison, it was argued that model projections of future food supply (some of which are based on older enclosure data) may have significantly overestimated the positive effect of elevated CO2 concentration on crop yields and, by extension, food security. However, in the comparison, no effort was made to differentiate ‘enclosure study’ methodologies with respect to maintaining projected CO2 concentration or to consider other climatic changes (e.g. warming) that could impact crop yields. In this review, we demonstrate that relative yield stimulations in response to future CO2 concentrations obtained using a number of enclosure methodologies are quantitatively consistent with FACE results for three crops of global importance: rice (Oryza sativa), soybean (Glycine max) and wheat (Triticum aestivum). We suggest, that instead of focusing on methodological disparities per se, improved projections of future food supply could be achieved by better characterization of the biotic/abiotic uncertainties associated with projected changes in CO2 and climate and incorporation of these uncertainties into current crop models.

Contents

Summary
607

I.
Rising CO2 and agricultural crop yields
608

II.
Expanding methodologies
608

III.
Which methodology gives the ‘truest’ prediction   of future yields?
608

IV.
Comparing responses among methodologies
610

V.
Methodology vs future uncertainty
611

VI.
Abiotic uncertainties
612

VII.
Biotic uncertainties
613

VIII.
Uncertainty vs methodology
614

IX.
Modelers and experimentalists
614

X.
Final thoughts
615

Acknowledgements
615

References
615
Understanding the relationship between holiday taking and self‐assessed health: an exploratory study of senior tourism
Authors: Hunter‐Jones Philippa , Blackburn Adele
Published: August 2007

The senior market is particularly attractive to the tourism industry. Alongside evidence of a growing propensity to travel and spend, consumption is often deliberately linked to low seasons, balancing out the peaks and valleys for tourism suppliers. Health is one variable which is particularly significant to this consumer. Personal health influences all patterns of consumer behaviour regardless of age, although the full extent to which this models senior tourism activity is unclear. An exploratory qualitative study was undertaken in the spring of 2005, with 22 senior consumers (aged 55 years plus) interviewed. Utilizing the earlier work by Zimmer et al.into self‐assessed health as a framework, travel propensity, the perceived effects of travel and factors inhibiting full participation were questioned. Conclusions drawn outline both a senior tourism typology and areas for future research. Notably the relationship between caregiving and tourism consumption is singled out for further investigation.
Exploring word‐of‐mouth influences on travel decisions: friends and relatives vs. other travellers
Authors: Murphy Laurie , Mascardo Gianna , Benckendorff Pierre
Published: August 2007

Travel research consistently shows the importance of word‐of‐mouth (WOM) information sources in the travel decision‐making process. Friends and relatives have been identified as organic image‐formation agents, and it has been emphasized that this WOM information is one of the most relied‐upon sources of information for destination selection. While there has been recognition of the importance of WOM information sources on consumer behaviour in tourism, little has been performed to understand more specifically how and what behaviour is influenced. This study examined the differing influences of friends and relatives vs. other travellers on the travel choices and behaviours of 412 visitors to the North Queensland Region in Australia. More specifically, the present study compared the following four groups of respondents: those who indicated that they obtained travel information from friends/relatives and other travellers (n = 70); those who obtained information from friends/relatives only (n = 121); those who obtained information from other travellers only (n = 105); and those who obtained information from neither (i.e. no WOM) (n = 116). The results indicated that there were significant differences across the four groups with respect to demographic characteristics, other information sources used, accommodation and transportation used, and travel activities in the destination. However, the groups did not differ in their image of the destination.
Information sources used by older adults for decision making about tourist and travel destinations
Authors: Patterson Ian
Published: August 2007

Over the past decade, the older market has emerged as an extremely important one because of its increased purchasing power for most consumer goods and services. The tourism and leisure industry is also targeting people aged 65 years and older, because many possess a relatively large share of discretionary money that they want to spend on travel. This has resulted in increasing attention by the mass media and the advertising industry in particular. This paper discusses the main types of information sources that are used by older adults when they make decisions about tourist and travel destinations, and particularly focuses on the importance of word‐of‐mouth sources and personal experiences. It also explores the influence of the mass media on trip decision making for older adults, and discusses the importance of brochures, magazines and television as information sources for older adults. Finally, it critiques the lack of senior models in advertising campaigns for travel products that are aimed at the older market.
β2‐ and β3‐Adrenoceptors activate glucose uptake in chick astrocytes by distinct mechanisms: a mechanism for memory enhancement?
Authors: Hutchinson Dana S. , Summers Roger J. , Gibbs Marie E.
Published: August 2007

Isoprenaline, acting at β‐adrenoceptors (ARs), enhances memory formation in single trial discriminated avoidance learning in day‐old chicks by mechanisms involving alterations in glucose and glycogen metabolism. Earlier studies of memory consolidation in chicks indicated that β3‐ARs enhanced memory by increasing glucose uptake, whereas β2‐ARs enhance memory by increasing glycogenolysis. This study examines the ability of β‐ARs to increase glucose uptake in chick forebrain astrocytes. The β‐AR agonist isoprenaline increased glucose uptake in a concentration‐dependent manner, as did insulin. Glucose uptake was increased by the β2‐AR agonist zinterol and the β3‐AR agonist CL316243, but not by the β1‐AR agonist RO363. In chick astrocytes, reverse transcription‐polymerase chain reaction studies showed that β1‐, β2‐, and β3‐AR mRNA were present, whereas radioligand‐binding studies showed the presence of only β2‐ and β3‐ARs. β‐AR or insulin‐mediated glucose uptake was inhibited by phosphatidylinositol‐3 kinase and protein kinase C inhibitors, suggesting a possible interaction between the β‐AR and insulin pathways. However β2‐ and β3‐ARs increase glucose uptake by two different mechanisms: β2‐ARs via a Gs‐cAMP‐protein kinase A‐dependent pathway, while β3‐ARs via interactions with Gi. These results indicate that activation of β2‐ and β3‐ARs causes glucose uptake in chick astrocytes by distinct mechanisms, which may be relevant for memory enhancement.
Canine distemper virus infection of primary hippocampal cells induces increase in extracellular glutamate and neurodegeneration
Authors: Brunner Jean‐Marc , Plattet Philippe , Majcherczyk Paul , Zurbriggen Andreas , Wittek Riccardo , Hirling Harald
Published: August 2007

The canine distemper virus (CDV) belongs to the Morbillivirus genus which includes important human pathogens like the closely related measles virus. CDV infection can reach the nervous system where it causes serious malfunctions. Although this pathology is well described, the molecular events in brain infection are still poorly understood. Here we studied infection in vitro by CDV using a model of dissociated cell cultures from newborn rat hippocampus. We used a recombinant CDV closely related to the neurovirulent A75/17 which also expresses the enhanced green fluorescent protein. We found that infected neurons and astrocytes could be clearly detected, and that infection spreads only slowly to neighboring cells. Interestingly, this infection causes a massive cell death of neurons, which includes also non‐infected neurons. Antagonists of NMDA‐type or alpha‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propinate (AMPA)‐type glutamate receptors could slow down this neuron loss, indicating an involvement of the glutamatergic system in the induction of cell death in infected and non‐infected cells. Finally, we show that, following CDV infection, there is a steady increase in extracellular glutamate in infected cultures. These results indicate that CDV infection induces excitotoxic insults on neurons via glutamatergic signaling.
Inhibition of heat shock proteins (HSP) expression by quercetin and differential doxorubicin sensitization in neuroblastoma and Ewing’s sarcoma cell lines
Authors: Zanini Cristina , Giribaldi Giuliana , Mandili Giorgia , Carta Franco , Crescenzio Nicoletta , Bisaro Brigitte , Doria Alessandra , Foglia Luiselda , Di Montezemolo Luca Cordero , Timeus Fabio , Turrini Franco
Published: August 2007

Neuroblastoma (NB) and Ewing’s sarcoma (ES) represent the most common extracranial solid tumors of childhood. Heat shock proteins (HSP) are elevated in cancer cells and their over‐expression was correlated to drug‐resistance. In this work we identified the HSP by a sensitive proteomic analysis of NB and ES cell lines, then, we studied the HSP response to doxorubicin. Some identified HSP were constitutively more expressed in NB than in ES cells. Doxorubicin‐stimulated HSP response only in NB cells. Quercetin was found to inhibit HSP expression depleting heat shock factor 1 (HSF1) cellular stores. Quercetin caused a higher anti‐proliferative effect in NB (IC50: 6.9 ± 5.8 μmol/L) than in ES cells (IC50: 85.5 ± 53.1 μmol/L). Moreover, quercetin caused a very pronounced doxorubicin sensitizing effect in NB cells (241 fold IC50 decrease) and a moderate effect in ES cells. HSP involvement in NB cells sensitization was confirmed by the silencing of HSF1. Quercetin treatment and HSF1 silencing increased the pro‐apoptotic effect of doxorubicin. In conclusion, the higher HSP levels, observed in NB cells, did not confer increased resistance to doxorubicin; on the contrary, HSP inhibition by quercetin or gene silencing caused higher sensitization to doxorubicin. These results may have a potential application in the treatment of NB.
Ethanol alters lipid profiles and phosphorylation status of AMP‐activated protein kinase in the neonatal mouse brain
Authors: Saito Mariko , Chakraborty Goutam , Mao Rui‐Fen , Wang Ray , Cooper Thomas B. , Vadasz Csaba , Saito Mitsuo
Published: August 2007

Previously, we have shown that ethanol‐induced apoptosis in cultured neurons is accompanied by changes in cellular lipid profiles. In the present study, the effects of ethanol on brain lipid metabolism were studied using 7‐day‐old C57BL/6ByJ mice, which display apoptotic neurodegeneration upon exposure to ethanol. The brain lipids were extracted 4–24 h after the ethanol or saline treatment, and analyzed by TLC. We found that the levels of triglyceride, cholesterol ester, ceramide, and N‐acylphosphatidylethanolamine increased significantly in the brains of ethanol‐treated mice compared to those of saline‐treated mice. Concomitantly, ethanol reduced Thr172 phosphorylation of AMP‐activated protein kinase (AMPK) α subunits. Ethanol also reduced phosphorylation of acetyl‐CoA carboxylase, a substrate of AMPK and a lipogenic enzyme known to be activated by dephosphorylation. In contrast, lipid profiles of 19‐day‐old mouse brains, which scarcely manifested neurodegeneration upon ethanol exposure, were not significantly affected by ethanol. Also, the basal levels of Thr172‐phosphorylated AMPK α were lower in these brains than in 7‐day‐old mouse brains, and no detectable changes in the phosphorylation status were observed by ethanol treatment. Our findings indicate that the ethanol‐induced apoptotic neurodegeneration observed in mice during restricted developmental periods is accompanied by alterations in both the lipid content and the activity of AMPK in the brain.
Cone arrestin binding to JNK3 and Mdm2: conformational preference and localization of interaction sites
Authors: Song Xiufeng , Gurevich Eugenia V. , Gurevich Vsevolod V.
Published: August 2007

Arrestins are multi‐functional regulators of G protein‐coupled receptors. Receptor‐bound arrestins interact with >30 remarkably diverse proteins and redirect the signaling to G protein‐independent pathways. The functions of free arrestins are poorly understood, and the interaction sites of the non‐receptor arrestin partners are largely unknown. In this study, we show that cone arrestin, the least studied member of the family, binds c‐Jun N‐terminal kinase (JNK3) and Mdm2 and regulates their subcellular distribution. Using arrestin mutants with increased or reduced structural flexibility, we demonstrate that arrestin in all conformations binds JNK3 comparably, whereas Mdm2 preferentially binds cone arrestin ‘frozen’ in the basal state. To localize the interaction sites, we expressed separate N‐ and C‐domains of cone and rod arrestins and found that individual domains bind JNK3 and remove it from the nucleus as efficiently as full‐length proteins. Thus, the arrestin binding site for JNK3 includes elements in both domains with the affinity of partial sites on individual domains sufficient for JNK3 relocalization. N‐domain of rod arrestin binds Mdm2, which localizes its main interaction site to this region. Comparable binding of JNK3 and Mdm2 to four arrestin subtypes allowed us to identify conserved residues likely involved in these interactions.
α2‐Adrenergic receptors activate cyclic AMP‐response element‐binding protein through arachidonic acid metabolism and protein kinase A in a subtype‐specific manner
Authors: Karkoulias Georgios , Mastrogianni Orthodoxia , Papathanasopoulos Panagiotis , Paris Hervé , Flordellis Christodoulos
Published: August 2007

On incubation with epinephrine, PC12 cells stably expressing α2‐adrenergic receptor (α2‐AR) undergo morphological and biochemical changes characteristic of neuron‐like differentiation. The present study shows that α2‐AR stimulation increases the phosphorylation of the transcription factor cAMP‐response element‐binding protein (CREB), the activity of a CRE‐reporter plasmid and the expression of cyclin D1 with subtype‐dependent efficiency (α2A ≈ α2C>> α2B). The effects of epinephrine were mimicked by cell exposure to forskolin or to exogenous arachidonic acid (AA) and they were abrogated by prior treatment with the inhibitor of phospholipase C (PLC) (U73122) or the inhibitor of cytochrome P450‐dependent epoxygenase, ketoconazole. On the other hand, treatment of the cells with epinephrine caused activation of protein kinase A (PKA), which was fully abolished by ketoconazole. Inhibition of PKA activity with H89 or ketoconazole abolished the effects of epinephrine on CREB, suggesting that activation of the cAMP/PKA pathway by AA epoxy‐derivatives is responsible for CREB activation by α2‐ARs. The effects of epinephrine were unaffected by LY294002. Furthermore, treatment with staurosporine, tyrphostin AG1478, PP1 or PD98059 did not change the extent of CREB phosphorylation but enhanced its transcriptional activity. Altogether, our results demonstrate that, in PC12 cells, the α2‐AR subtypes cause phosphorylation and activation of CREB through a pathway involving stimulation of PLC, AA release, generation of epoxygenase derivative and increase of PKA activity. They also suggest attenuation of CREB transcriptional activity by mitogen‐activated protein kinase, protein kinase C and Src kinases.
Stepping up to Motherhood among Inner-City Teens
Authors: Shanok Arielle F. , Miller Lisa
Published: August 2007

This mixed-methods, context-oriented study explored transitions to motherhood among pregnant and newly parenting inner-city teenagers ( n = 80) attending an alternative public school. Additionally, a novel research approach was assessed. Using data from a 2-year psychotherapy trial, inductive content analyses of therapy sessions and post hoc interviews of clinicians were synthesized with questionnaires and other more traditional data sources to develop a strength-focused understanding of prominent life themes, as experienced by participants. Results suggested that, although few teens had planned to have a baby, a large majority were pleased to discover their pregnancies. A heightened sense of purpose emerged, connected with drastically increased safety-conscious behaviors. Still, public and familial alienation was common. Grandmothers and additional female mentors became central, and their support of the pregnancy was protective against teen mothers' depression. The research technique assessed in this study provided broad-ranging information with substantial validity and minimal time and expense.
Voice Matters: Buffering the Impact of a Negative Climate for Women in Science
Authors: Settles Isis H. , Cortina Lilia M. , Stewart Abigail J. , Malley Janet
Published: August 2007

The current study examined whether women scientists' perceptions of voice moderate the impact of poor workplace climates on job satisfaction and whether effective leadership and mentoring promote women's voice. Survey data were collected from 135 faculty women in the natural sciences. The results from multiple regression analyses indicated that negative (e.g., sexist, hostile) departmental climates were related to lower job satisfaction. However, voice interacted with climate, such that women who perceived that they had more voice in departmental matters showed higher levels of job satisfaction than those who perceived having less voice. An additional regression indicated that mentoring by other women (but not men) in academia and effective departmental leadership were positively related to women's sense of voice. Theoretical and practical implications for the retention and success of women in male-dominated fields are discussed.
University Students from Single-Sex and Coeducational High Schools: Differences In Majors and Attitudes at a Catholic University
Authors: Karpiak Christie P. , Buchanan James P. , Hosey Megan , Smith Allison
Published: August 2007

We conducted an archival study at a coeducational Catholic university to test the proposition that single-sex secondary education predicts lasting differences in college majors. Men from single-sex schools were more likely to both declare and graduate in gender-neutral majors than those from coeducational schools. Women from single-sex schools were more likely to declare gender-neutral majors, but were not different from their coeducated peers at graduation. A second study was conducted with a sample of first-year students to examine the correspondence between egalitarian attitudes, single-sex secondary education, and major choice. Egalitarianism was higher in students in nontraditional majors, but did not correspond in expected ways with single-sex education. Men from single-sex schools were less likely to hold egalitarian attitudes about gender roles, whereas women from single-sex and coeducational high schools did not differ in egalitarianism. Taken together, our results raise questions about the potential of single-sex high schools to reduce gender-stratification in professions.
Gender, Discrimination Beliefs, Group-Based Guilt, and Responses to Affirmative Action for Australian Women
Authors: Boeckmann Robert J. , Feather N. T.
Published: August 2007

Views of a selection committee's decision to promote a woman over a man on the basis of affirmative action were studied in a random sample of Australians (118 men and 111 women). The relations between perceptions of workplace gender discrimination, feelings of collective responsibility and guilt for discrimination, and judgments of entitlement to and, secondarily, deservingness of affirmative action were examined. AMOS analyses indicated that men's reports of collective guilt predicted attitudes toward women's entitlement. No coherent model was observed for women, which suggested ambivalent attitudes toward affirmative action. Gender differences in discrimination beliefs also suggested that women believe men are unfairly advantaged and that men believe women are responsible for their own disadvantage. Implications for research examining collective emotions and their role in social justice judgments are discussed.
Isolation and characterization of microsatellite markers from the white‐ruffed manakin Corapipo altera (Aves, Pipridae)
Authors: BARNETT JACOB R. , STENZLER LAURA M. , RUIZ‐GUTIERREZ VIVIANA , BOGDANOWICZ STEVEN M. , LOVETTE IRBY J.
Published: August 2007

We describe 15 polymorphic microsatellite loci from the white‐ruffed manakin Corapipo altera, a common understory bird of Neotropical lowland and montane evergreen forests from eastern Honduras to northwestern Colombia. These markers were developed in order to assess population structure and genetic diversity in a fragmented landscape, and to study gene flow between forest fragments. Primers were tested on a population of 159 individuals from the Coto Brus region of southwestern Costa Rica. We found between four and 23 alleles per locus, and observed heterozygosities ranging from 0.23 to 0.93.
Lymphohematopoietic progenitors do not have a synchronized defect with age‐related thymic involution
Authors: Zhu Xike , Gui Jingang , Dohkan Junichi , Cheng Lili , Barnes Peter F. , Su Dong‐Ming
Published: August 2007

It has been speculated that aging lymphohematopoietic progenitor cells (LPC) including hematopoietic stem cells (HSC) and early T‐cell progenitors (ETP) have intrinsic defects that trigger age‐related thymic involution. However, using a different approach, we suggest that that is not the case. We provided a young thymic microenvironment to aged mice by transplanting a fetal thymus into the kidney capsule of aged animals, and demonstrated that old mouse‐derived LPCs could re‐establish normal thymic lymphopoiesis and all thymocyte subpopulations, including ETPs, double negative subsets, double positive, and CD4+ and CD8+ single positive T cells. LPCs derived from aged mice could turn over young RAG−/– thymic architecture by interactions, as well as elevate percentage of peripheral CD4+IL‐2+ T cells in response to costimulator in aged mice. Conversely, intrathymic injection of ETPs sorted from young animals into old mice did not restore normal thymic lymphopoiesis, implying that a shortage and/or defect of ETPs in aged thymus do not account for age‐related thymic involution. Together, our findings suggest that the underlying cause of age‐related thymic involution results primarily from changes in the thymic microenvironment, causing extrinsic, rather than intrinsic, defects in T‐lymphocyte progenitors.