bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of released Eurasian otters on a population of American mink: a test using an experimental approach
Authors: Bonesi L. , Macdonald D. W.
Published: May 2004

Competition is considered to be a major evolutionary driving force within assemblages of related and morphologically similar species, but it is notoriously difficult to test and quantify especially amongst species that cannot be easily manipulated in a laboratory or in the field. By exploiting a re‐introduction of Eurasian otters (Lutra lutra) in the Upper Thames catchment (UK) in 1999 we performed an experiment to test whether there was evidence of competition between otters and American mink (Mustela vison). Mink and otters are semi‐aquatic mustelids belonging to the same guild. Otters are expected to be the dominant competitor because they are larger and better adapted at exploiting aquatic resources. Our hypothesis was that mink declines when the density of otters increases. We measured the effect of competition at the population level, by observing whether mink distribution and densities changed in an area of 1353 km2 in association with the arrival of its putative competitor. We estimated distribution and densities by means of sign surveys and trapping. The results showed that otters were associated with a significant and rapid reduction in the densities of mink, while mink occupancy remained approximately the same in an area of 2464 km2 that was used as a control. We observed that the spatial distribution of the mink population throughout its decline was influenced by the yearly cycle of mink activities, with areas being temporarily re‐colonized during the dispersal season. Mink is an invasive species in the UK threatening the survival of some native species. Our findings suggest that the re‐establishment of otter populations is likely to lead to a decline of mink that may, in turn, be beneficial to native species threatened by this invasive.
Preservation of soft tissues in Silurian graptolites from Latvia
Authors: Loydell David K. , Orr Patrick J. , Kearns Stuart
Published: May 2004

The contractile stalks of graptoloid zooids are preserved as organic carbon residues in thecae of the middle Llandovery graptoloid graptolites Rastrites geinitzii and Neolagarograptus? sp. from the Aizpute‐41 core, Latvia. The contractile stalks are surrounded by equant pyrite crystals, resulting in three‐dimensional preservation of the graptolite rhabdosomes, and are associated with sediment of similar composition to, and derived from, the adjacent matrix. Matrix entered the thecae after pyrite crystal growth and filled some of the space left by collapse of the contractile stalks and some intercrystalline cavities; other space is partially infilled by diagenetic minerals. The contractile stalks are parallel‐sided and occupy up to one‐half the metathecal width, which is not inconsistent, assuming post‐mortem shrinkage, with the suggestion that graptoloid zooids filled their thecal tubes in life. The location of the preserved soft tissues, towards the distal ends of the metathecae, is very different from that predicted by decay experiments on the extant pterobranch hemichordate Rhabdopleura; the latter's soft tissues may thus not be a reliable analogue for those of these Silurian graptoloids.
Recent brachiopods from the southern Brazilian shelf: palaeontological and biogeographical implications
Authors: Simões Marcello G. , Kowalewski Michał , Mello Luiz H. C. , Rodland David L. , Carroll Monica
Published: May 2004

Until recently, the rhynchonelliform (articulated) brachiopod fauna from the Brazilian continental shelf (western South Atlantic) was represented only by the endemic species Bouchardia rosea (Mawe), reported from coastal waters of the states of São Paulo and Rio de Janeiro. The present study, based on samples from coastal (<30 m), shelf, and continental slope waters (99–485 m), documents the South Atlantic brachiopod fauna and shows that this fauna is more widespread, diverse, and cosmopolitan than previously thought. Based on a total of 16,177 specimens, the following brachiopods have been identified: Bouchardia rosea (Family Bouchardiidae), Platidia anomioides (Family Platidiidae), Argyrotheca cf. cuneata (Family Megathyrididae), and Terebratulina sp. (Family Cancellothyrididae). In coastal settings, the fauna is overwhelmingly dominated by Bouchardia rosea. Rare juvenile (<2 mm) specimens of Argyrotheca cf. cuneata were also found at two shallow‐water sites. In shelf settings (100–200 m), the fauna is more diverse and includes Bouchardia rosea, Terebratulina sp., Argyrotheca cf. cuneata, and Platidia anomioides. Notably, Bouchardia rosea was found in waters as deep as 485 m, extending the known bathymetric range of this genus. Also, the record of this brachiopod in waters of the state of Paraná is the southernmost known occurrence of this species. The genera Platidia and Terebratulina are documented here for the first time for the western South Atlantic. The Brazilian brachiopod fauna shares similarities with those from the Atlantic and Indian shelves of southern Africa, and from the Antarctic, Caribbean and Mediterranean waters. The present‐day brachiopods of the western South Atlantic are much more cosmopolitan than previously thought and their Cenozoic palaeobiogeographic history has to be reconsidered from that perspective.
Neoselachian sharks and rays from the British Bathonian (Middle Jurassic)
Authors: Underwood Charlie J. , Ward David J.
Published: May 2004

Extensive sampling of Bathonian sediments from localities across southern and central England has produced over 8000 neoselachian teeth. These comprise diverse faunas, with over 25 species being represented in total, most of them previously undescribed. Seventeen new species and seven new genera are named: Palaeoscyllium tenuidens sp. nov., Praeproscyllium oxoniensis gen. et sp. nov., Eypea leesi gen. et sp. nov., Proheterodontus sylvestris gen. et sp. nov., Paracestracion bellis sp. nov., Palaeobrachaelurus mussetti sp. nov., Heterophorcynus microdon gen. et sp. nov., Dorsetoscyllium terraefullonicum gen. et sp. nov., Ornatoscyllium freemani gen. et sp. nov., Pseudonotidanus semirugosus gen. et sp. nov., Synechodus duffini sp. nov., Protospinax magnus sp. nov., P. bilobatus sp. nov., P. carvalhoi sp. nov., Belemnobatis kermacki sp. nov., B. stahli sp. nov. and Spathobatis delsatei sp. nov. In addition, a new family, the Pseudonotidanidae fam. nov., is defined and the status of Paranotidanus Ward and Thies, 1987, Hybodus levis Woodward, 1889 and Breviacanthus brevis (Phillips, 1871) are discussed. These taxa show strong facies specificity, with different species being restricted to different palaeoenvironments.
On Re‐Orientalizing the Indian Novel: A Case Study of Rohinton Mistry's A Fine Balance
Authors: Almond Ian
Published: May 2004

This study of Rohinton Mistry's recent novel A Fine Balance offers an interpretation of the novel's central themes of resistance and resignation in the light of an earlier Indian classic, Mulk Raj Anand's 1935 work Untouchable, and in particular concentrates on the Yeatsian influence present in the novel, beginning with its title. In contrast to Anand's work, where the British and the caste‐system are revealed to be the key perpetrators of the protagonists’ sufferings, there is no single source of evil responsible for the myriad difficulties Mistry's characters suffer. The influence of Yeats and in particular his concept of the calm, stoic East, re‐orientalizes Mistry's text in quite an unexpected way. A Westerner's understanding of the East as the antithesis of tragedy seeps into the novel, offering an almost mystical alternative to the bleak political landscape the book surveys.

Ishvar nodded. ‘‘And are the two children happy without Monkey‐Man?’’ Beggarmaster flipped his unchained hand in a who‐knows gesture. ‘‘They will have to get used to it. Life does not guarantee happiness’’. ‐A Fine Balance, 542
The arts and social inclusion: what's the evidence?
Authors: Kinder Kay , Harland John
Published: May 2004

This article reviews some key findings from the National Foundation for Education Research (NFER) in two major research areas: strategies to address pupil disaffection, and arts education, focusing on overlap and commonality in reported effects and also effective practice. Its central question is whether, how and why arts education might make a contribution to those strategies aimed at addressing (or preventing) young people's disengagement from learning and educational opportunity. The authors discuss the key factors associated with successful re‐engagement and those linked to effective arts education, and conclude with evidence‐based questions to consider if arts education is to have a higher profile in the social inclusion agenda.
Arts, education and society: the role of the arts in promoting the emotional wellbeing and social inclusion of young people
Authors: Karkou Vassiliki , Glasman Judy
Published: May 2004

In our second article, Vassiliki Karkou and Judy Glasman provide an illuminating overview of current debates about the place of the arts within education. They explore the emotional and social role of the arts in school, illustrating their discussion with insights gained from the Labyrinth Project, an arts‐based prevention programme developed in schools in Hertfordshire and North London.
Promoting inclusion in school through the arts: a case study
Authors: Wetz James
Published: May 2004

In this article James Wetz describes and reflects on his experience as Principal of a Specialist Performing Arts College and Post‐16 Centre. His account will be of great interest to colleagues in the growing number of such schools. Of particular interest is the pervading clarity of purpose and willingness to accept the challenge presented by the arts and to address the sometimes uncomfortable issues they raise.
Risking creativity: building the creative context
Authors: Balshaw Maria
Published: May 2004

In this lively account of a special school's involvement with the government‐funded Creative Partnership programme, Maria Balshaw provides a helpful overview of that programme and demonstrates the exciting potential for inclusive practice when schools work in partnership with creative professionals.
‘A struggle well worth having’: the uses of theatre‐in‐education (TIE) for learning
Authors: Cooper Chris
Published: May 2004

In this article Chris Cooper conveys something of his passionate belief in the importance of attending to the preconditions of learning. He stresses the crucial role of the imagination in this, bringing, as he puts it, ‘creativity to the process of learning’. His account of a drama project based on The Tempest provides important insights into the working of these processes. Many readers, as an added bonus, will be interested in the observer role of the learning support assistant.
Including the excluded: an art in itself
Authors: Tranter Rachel , Palin Nathalie
Published: May 2004

Rachel Tranter and Nathalie Palin are involved with programmes created in partnership with a range of education providers, particularly Pupil Referral Services in West London. Here they discuss their work at the Orleans House Gallery, providing insights into the scope and potential of the arts and inclusion. In this article they raise issues for sustaining and developing the work for the benefit of participants and partner organisations alike.
Cyclic release of carbon dioxide accompanied by abdominal telescoping movements in forager ants of Formica polyctena (Hymenoptera, Formicidae)
Authors: Kuusik Aare , Martin Ants‐Johannes , Mänd Marika , Metspalu Luule , Tartes Urmas , Lind Ave
Published: May 2004

Abstract.  Discontinuous gas exchange and abdominal telescoping movements were investigated in intact forager ants of Formica polyctena Förster. For simultaneous recording of discontinuous gas exchange and abdominal movements, an electrolytic differential microrespirometer was combined with an infrared‐optical device using an infrared‐sensor diode commonly applied as a cardiograph in insect studies. The air in the insect chamber was saturated with water vapour, and an ant was contacted with a sliver of wet filter paper. Accordingly, the ants used in the experiments were regarded as being hydrated. The enforced immobility of the ant in the respirometry chamber (0.15 mL volume) induced continuous struggling during the first hours of measurement but, after 3–4 h, the activity periods alternated with quiescent periods when regular cycles of discontinuous gas exchange (8.97 mHz) were displayed. After remaining in the chamber for a day, the ants showed such cycles (8.15 mHz) without any interruption by periods of activity. The cyclic release of carbon dioxide (burst) was accompanied by a bout of telescoping movements of the abdominal segments (rapid contractions and slow relaxations), which were interpreted as active ventilation. The irregular and rare abdominal contractions, recorded during the interburst periods on the first day of measurements, were regarded as a symptom of stress because these disappeared on the second day. In approximately 20% of foragers, the telescoping movements during the interburst periods were characterized by very rapid (0.09 s) protractions and slow retractions of the abdominal segments, obviously acting as inspiration movements. The results do not support the hypothesis that discontinuous gas exchange is an adaptation for conserving water in ants.
Arabidopsis thaliana leaf‐surface extracts are detected by the cabbage root fly (Delia radicum) and stimulate oviposition
Authors: Marazzi Cristina , Städler Erich
Published: May 2004

Abstract. Oviposition of the cabbage root fly, Delia radicum (Diptera, Anthomyiidae) is stimulated by leaf‐surface extracts of Arabidopsis thaliana (L.) Heynh. (Brassicaceae) ecotype Columbia. The leaf surface of A. thaliana, similar to that of many other crucifers, contains glucosinolates and CIF (‘cabbage identification factor’; 1,2‐dehydro‐3‐thia‐4,10,10b‐triaza‐cyclopenta[.a.]fluorene‐1‐carboxylic acid). These compounds stimulate receptor neurones of the tarsal sensilla of D. radicum whereas additional, unknown compounds are detected by other receptor neurones.
Oviposition habitat selection by mosquitoes in response to predator (Notonecta maculata) density
Authors: Eitam Avi , Blaustein Leon
Published: May 2004

Abstract.  Some species of mosquitoes can detect the presence of predatory notonectid bugs and avoid oviposition in predator pools. The oviposition response of two mosquito species, Culiseta longiareolata Macquart and Culex laticinctus Edwards (Diptera: Culicidae), to a range of densities of the predator, Notonecta maculata Fabricius (Heteroptera: Notonectidae), was tested here. Densities of 0, 1, 2 or 4 Notonecta were established in 30‐L artificial pools. Both mosquito species oviposited less in predator pools, but the response was unrelated to predator density, whereas vulnerability of Culiseta immatures to predation was density‐dependent. Thus, although mosquitoes can detect Notonecta at any density within the range tested, they may be unable to discriminate among predator densities. The avoidance of predator pools by Culiseta, as well as its vulnerability to predation, occurred to a lesser degree than in earlier studies. This may have been due to the mitigating effects of components of the biotic community.
Host plant affects pollen beetle (Meligethes aeneus) egg size
Authors: Ekbom Barbara , Popov Sergei Y. A.
Published: May 2004

Abstract.  In some herbivorous insect species, egg size is larger on low‐quality hosts than on high‐quality hosts and may be related to the prospect that larger offspring are more likely to survive on a poor host. Sizes of eggs laid by pollen beetles [Meligethes aeneus Fab. (Coleoptera: Nitidulidae)] were examined with insects confined on one of two different host plants that had previously shown differences in adult preference and larval performance. Individual females were also exposed sequentially to both the low‐quality host (Sinapis alba L.) and the high‐quality host (Brassica napus L.) and the size of their eggs was determined. Pollen beetles laid shorter eggs on low‐quality hosts both for different females on different host plants and for the same individuals on different host plants, in contrast to the prediction that low‐quality hosts would receive larger eggs than high‐quality hosts. Previously, egg production rate was shown to be reduced when pollen beetles are exposed to low‐quality hosts and it is suggested that oogenesis is incomplete, resulting in shorter eggs. The possibility that this is related to antibiosis on S. alba is discussed.
Behavioural evidence for a female sex pheromone in Cotesia flavipes (Hymenoptera: Braconidae)
Authors: De Freitas Maria Do Rosário T. , De Lima MendonÇa Adriana , Nascimento Ruth Rufino Do , Sant'Ana Antônio Euzébio G.
Published: May 2004

Abstract.  The mating behaviour of Cotesia flavipes Cameron, 1891 (Hymenoptera: Braconidae) was observed under laboratory conditions. The results demonstrate that chemical stimuli play an important role in bringing males and females together for mating. Females from this species release chemical compounds to attract males, which exhibit a distinct courtship behaviour divided into three main steps: (i) antennation, (ii) lateral bouncing and (iii) wing fluttering. Ethological tests using hexane extracts from two different parts of the female's body (head plus thorax and abdomen) demonstrate that males are more attracted and also display a courtship behaviour when a filter paper containing hexane extracts from the abdomen is presented to them, indicating that the abdomen is the source of the sex pheromone of this species. Naive males of this species respond to hexane extracts of this gland by displaying courtship behaviour. Furthermore, additional tests show that C. flavipes females mate only once, whereas virgin males do not show any preference for virgin or mated females, suggesting that mated females of this species continue to produce sex attractants after mating.
Nurse Home Visits to Maternal–Child Clients: A Review of Intervention Research
Authors: McNaughton Diane B.
Published: May 2004

Abstract  Home visiting has been considered a promising strategy for addressing the multiple needs of families at risk. Research reviews are a valuable resource for researchers, policymakers, and practitioners who develop and support new home‐visiting interventions. This review examines 13 research studies published between the years of 1980 and 2000 that test the effectiveness of home‐visiting interventions using professional nurses as home visitors. Findings indicate that a wide range of client problems are addressed during home visits using a variety of nursing interventions. Missing from most of the reports is a clear theoretical link between the client problem addressed, the nursing intervention, and target outcomes. About half of the studies were successful in achieving desired outcomes. Future research should be directed by middle‐range practice theory, clearly explicate the nursing intervention being tested, use power analysis to determine sample size, and report reliability and validity of dependent variable measures with culturally diverse samples.
Barriers to Effective Contraception and Strategies for Overcoming Them Among Adolescent Mothers*
Authors: Breheny Mary , Stephens Christine
Published: May 2004

Abstract  Young women often have difficulty accessing and correctly using contraception. However, these difficulties are not primarily the result of lack of knowledge or experience of contraception. In this study, nine adolescent mothers were interviewed about their experience of contraception before and after the birth of their children. These adolescent women faced barriers to effective contraceptive use before the birth of their children. These barriers included indifference to the possibility of pregnancy, perceived invulnerability to pregnancy, and forgetting to use contraception regularly. Analysis also revealed that during the time these women were sexually active prior to pregnancy, many had used a range of strategies to overcome these barriers to effective contraception, including using adult support, allowing an adult to take responsibility for contraception, and using multiple methods of contraception to cover for contraceptive failure. The strategies used by these women to delay childbearing indicate valuable areas for further research in preventing unplanned adolescent pregnancy.
Childhood Vaccine Risk/Benefit Communication Among Public Health Clinics: A Time‐Motion Study
Authors: Davis Terry C. , Fredrickson Doren D. , M. Kennen Estela , Arnold Connie , Shoup Eileen , Sugar Mackey , Humiston Sharon G. , Bocchini Joseph A.
Published: May 2004

Abstract  United States law requires that immunization providers use Centers for Disease Control Vaccine Information Statements (VISs) and inform parents about vaccine risks and benefits prior to every childhood immunization. A recent national survey found that public health clinics (PHCs) reported high compliance with this law. To further investigate these findings, we conducted an immunization time‐motion study in two PHCs in Kansas and Louisiana. Research assistants observed a convenience sample of 246 child immunization visits to record distribution of the VISs and content and time of vaccine communication. Thirty percent of parents read below a ninth grade level, 53% had Medicaid insurance, and 56% were Black. VISs were given with every dose of vaccine administered in 89% of visits. Public health nurses (PHNs) frequently discussed potential vaccine side effects (91%), treatment of side effects (91%), and the vaccine schedule (93%). Contraindications were screened in 71% of visits. Benefits were discussed in 48% of visits and severe risks in 29%. The national Vaccine Injury Compensation Program (VICP) was never discussed. The immunization visits lasted for a mean of 20 min. Vaccine communication of side effects, risks, benefits, screening for contraindications, and the next visit lasted for an average of 16 s for all vaccines. PHC compliance with mandated VIS distribution and practical vaccine communication was high. Room for improvement exists in discussion of benefits, serious risks, and the VICP.
Public Health Nurses' Perspectives on Collaborative Partnerships in South Africa
Authors: Ansari Walid El , Phillips Ceri J. , Zwi Anthony B.
Published: May 2004

Abstract  The importance of partnerships and collaborations between different stakeholders in order to achieve health objectives are increasingly recognized. This article aims to: (1) highlight the importance of establishing partnerships and coalitions to achieve health goals; (2) consider the benefits and costs of such collaborations; and (3) identify the conditions which facilitate effective partnerships, from the perspective of nurses working within collaborative ventures in South Africa. A survey of these nurses was undertaken to consider their perceptions of the likely returns from investments in collaborative working and the extent of the relationship between the participation incentives and difficulties encountered. By examining their perceptions to a number of facets of partnership fostering, the article has elaborated on the meaning of collaboration and its rationale, and highlighted the conditions necessary for the success of community partnerships (CPs). The study has also demonstrated the feeling that CPs are beneficial with increased satisfaction along many operational parameters. Working to a shared agenda requires a “give and take attitude” among the stakeholders, designed to produce an outcome that merges multiple and new insights and directions for action, as well as the combined power foundation to do so.
The Evolution of the Community Health Nurse Practitioner in Korea
Authors: Cho Ho Soon Michelle , Kashka Maisie Schmidt
Published: May 2004

Abstract  Community health nursing in Korea has undergone dramatic changes since 1980. These changes arose through the efforts of Mo Im Kim, an internationally known leader in Korean nursing, and colleagues who successfully worked to establish a national community health nurse practitioner program. This article will review these changes with the aim of describing the evolutionary process that culminated in a community health care system that is meeting the needs of Korean citizens who live in rural and isolated areas. The authors believe that the evolution of the community health nurse practitioner in Korea provides a paradigm that can serve as a model for other countries. Health care in Korea is organized differently than that in the United States. However, the plan, process, and political activism can be used for community and public health nursing change in the United States. The information contained in this article is based upon interviews with Mo Im Kim and 20 of her colleagues and associates. Interviewees were selected using a “snowball” sampling technique. Additional data were derived from various professional and personal documents of these individuals. The first author conducted the interviews in both Korea and in the United States.
Maternal Depression and Anxiety and Infant Development: A Comparison of Foreign‐Born and Native‐Born Mothers
Authors: Foss Gwendolyn F. , Chantal Andjukenda W. , Hendrickson Simone
Published: May 2004

Abstract  Studies that investigate infant and/or child development in families of depressed or anxious mothers do not include samples of foreign‐born non‐English‐speaking mothers. This article describes a pilot study investigating infant development, maternal depression, and anxiety in comparison samples of native‐born and foreign‐born mothers and children from Vietnam, Laos (Hmong), and the Democratic Republic of Congo. Maternal depression and anxiety were measured with the Hopkins Symptom Checklist‐25, and the developmental status of children 0–25 months of age was measured with the Denver II. Foreign‐born mothers were more anxious than native‐born mothers. Non‐English‐speaking foreign‐born mothers were clinically depressed (1.83) and moderately anxious (1.62). Infants of native‐born mothers and English‐speaking foreign‐born mothers performed better on the Denver II than children of foreign‐born non‐English‐speaking mothers. Infants and toddlers of non‐English‐speaking mothers appear to be at high risk for delays during their first 25 months of life. Public health nurses need to advocate for appropriate interpreter services and mental health resources for non‐English‐speaking mothers of young children. Developmental screening should reflect cultural variations in parental expectations of how and when children meet developmental milestones. Replication studies and investigation about the long‐term development of this high‐risk group of children are needed.
Effectiveness of Home Visit Falls Prevention Strategy for Taiwanese Community‐Dwelling Elders: Randomized Trial
Authors: Huang Tzu‐Ting , Acton Gayle J.
Published: May 2004

Abstract  The purpose of this research was to examine the effect of a multifactorial intervention to prevent falls by increasing self‐efficacy to prevent falls, improving the knowledge of medication safety, and decreasing the number of environmental risks in older persons dwelling in the community. A sample of 120 cognitively intact residents of this community who were 65 years of age and older were recruited into a two‐group pretest–post‐test experimental design and randomly assigned to an experimental group and a comparison group (60 in each group). The intervention was delivered, and data were collected during three home visits in a 4‐month period. (1) Experimental subjects improved their fall self‐efficacy, environmental safety, and knowledge of medication safety significantly (p < 0.01) as compared with those in the comparison group at post‐test; (2) the incidence of falls was reduced at post‐test in both groups compared to pretest scores, and the falling was more serious in the comparison group at post‐test compared to that in the experimental group. The results can help community health professionals to individualize their interventions to the specific needs of the elderly, thus helping to prevent falls among community‐dwelling elders.
How Much Public Health in Public Health Nursing Practice?
Authors: Grumbach Kevin , Miller Janet , Mertz Elizabeth , Finocchio Len
Published: May 2004

Abstract  Public health nursing (PHN) practice is defined by an emphasis on population health issues rather than individually focused clinical interventions, but the actual scope and focus of PHN practice have not been well documented. The purpose of this survey was to investigate the practice activities, priorities, and education of public health nurses in California. Public health nurses in five counties were surveyed about interventions targeted at individual–family, community, and system levels. Summary scales (range: 1–4) were created to measure self‐rated PHN activity, importance, and education at each level. Staff were most likely to perform individual–family level interventions (mean score, m=2.55), followed by community (m=1.86) and system‐level interventions (m=1.46). Managers rated individual–family level interventions as most important (m=2.91) and community‐level interventions (m=2.42) as more important than those at the system level (m=1.99). Individually focused case management was the most frequently performed and highly valued intervention. Staff and manager‐directors deemed individual–family interventions as the area in which public health nurses were best educated, followed by community and then system interventions. Results indicate that the population health focus of public health nursing is not reflected in the practice activities, management priorities, or educational preparation of public health nurses.
Substance identification by quantitative characterization of oscillatory activity in murine spinal cord networks on microelectrode arrays
Authors: Gramowski Alexandra , Jügelt Konstantin , Weiss Dieter G. , Gross Guenter W.
Published: May 2004

This paper presents a novel and comprehensive method to identify substances on the basis of electrical activity and is a substantial improvement for drug screening. The spontaneous activity of primary neuronal networks is influenced by neurotransmitters, ligands, and other substances in a similar fashion as known from in vivo pharmacology. However, quantitative methods for the identification of substances through their characteristic effects on network activity states have not yet been reported. We approached this problem by creating a database including native activity and five drug‐induced oscillatory activity states from extracellular multisite recordings from microelectrode arrays. The response profiles consisted of 30 activity features derived from the temporal distribution of action potentials, integrated burst properties, calculated coefficients of variation, and features of Gabor fits to autocorrelograms. The different oscillatory states were induced by blocking neurotransmitter receptors for: (i) GABAA; (ii) glycine; (iii) GABAA and glycine; (iv) all major synaptic types except AMPA, and (v) all major synapses except NMDA. To test the identification capability of the six substance‐specific response profiles, five blind experiments were performed. The response features from the unknown substances were compared to the database using proximity measures using the normalized Euclidian distance to each activity state. This process created six identification coefficients where the smallest correctly identified the unknown substances. Such activity profiles are expected to become substance‐specific ‘finger prints’ that classify unique responses to known and unknown substances. It is anticipated that this kind of approach will help to quantify pharmacological responses of networks used as biosensors.
Nicotine reduces Aβ in the brain and cerebral vessels of APPsw mice
Authors:   Ewa Hellström‐Lindahl,, Court Jennifer , Keverne Jessica , Svedberg Marie , Lee Mandy , Marutle Amelia , Thomas Alan , Perry Elaine , Bednar Ivan , Nordberg Agneta
Published: May 2004

Ten days treatment with nicotine reduced insoluble amyloid Aβ1–40 and Αβ1–42 peptides by 80% in the cortex of 9‐month‐old APPsw mice, which is more than that observed in 14.5‐month‐old mice following nicotine treatment for 5.5 months. A reduction in Aβ associated with cerebral vessels was observed in addition to that deposited as parenchymal plaques after 5.5 months treatment. The diminution in Aβ peptides observed was not accompanied by changes in brain α, β or γ secretase‐like activities, NGF or BDNF protein expression measured in brain homogenates. A significant increase in sAPP was observed after nicotine treatment of SH‐SY5Yneuroblastoma cells that could be blocked by the nicotinic antagonist mecamylamine. Attenuation of elevated [125I]‐αbungarotoxin binding (α7) in APPsw mice was observed after 5.5 months nicotine treatment. Both these observations suggest that the reduction in insoluble Aβ by nicotine might be in part mediated via the α7 nicotinic receptor. Further studies are required to identify potential mechanisms of the nicotine's amyloid‐reducing effect.
TrkA and mitogen‐activated protein kinase phosphorylation are enhanced in sympathetic neurons lacking functional p75 neurotrophin receptor expression
Authors: Hannila Sari S. , Lawrance Gail M. , Ross Gregory M. , Kawaja Michael D.
Published: May 2004

This study examined the effects of hypomorphic p75 neurotrophin receptor (p75NTR) expression and high levels of nerve growth factor (NGF) on trkA phosphorylation and downstream activation of p44/42 mitogen‐activated protein kinase (MAPK). Post‐ganglionic sympathetic neurons from postnatal day 1 p75NTR exon III null mutant (p75−/−) and 129/SvJ mice were cultured in the presence of 50 ng/mL NGF and analysed by Western blotting. Levels of phosphorylated trkA are increased in p75−/− neurons compared with 129/SvJ neurons, and these higher levels are maintained with continuous exposure to NGF. MAPK is also phosphorylated to a greater extent in p75−/− neurons than in 129/SvJ neurons, both within 10 min of exposure to NGF, and with continuous NGF treatment for 5 days. These data provide new insight into the mechanism underlying enhanced neurite outgrowth in p75−/− neurons, demonstrating that trkA and MAPK signalling in sympathetic neurons are increased when p75NTR function is disrupted.
The basal ganglia network mediates the planning of movement amplitude
Authors: Desmurget M. , Grafton S.T. , Vindras P. , Gréa H. , Turner R. S.
Published: May 2004

This study addresses the hypothesis that the basal ganglia (BG) are involved specifically in the planning of movement amplitude (or covariates). Although often advanced, based on observations that Parkinson's disease (PD) patients exhibit hypokinesia in the absence of significant directional errors, this hypothesis has been challenged by a recent alternative, that parkinsonian hypometria could be caused by dysfunction of on‐line feedback loops. To re‐evaluate this issue, we conducted two successive experiments. In the first experiment we assumed that if BG are involved in extent planning then PD patients (who exhibit a major dysfunction within the BG network) should exhibit a preserved ability to use a direction precue with respect to normals, but an impaired ability to use an amplitude precue. Results were compatible with this prediction. Because this evidence did not prove conclusively that the BG is involved in amplitude planning (functional deficits are not restricted to the BG network in PD), a second experiment was conducted using positron emission tomography (PET). We hypothesized that if the BG is important for planning movement amplitude, a task requiring increased amplitude planning should produce increased activation in the BG network. In agreement with this prediction, we observed enhanced activation of BG structures under a precue condition that emphasized extent planning in comparison with conditions that emphasized direction planning or no planning. Considered together, our results are consistent with the idea that BG is directly involved in the planning of movement amplitude or of factors that covary with that parameter.
Elevation of intracellular cAMP evokes activity‐dependent release of adenosine in cultured rat forebrain neurons
Authors: Lu Yin , Li Ya , Herin Greta Ann , Aizenman Elias , Epstein Paul M. , Rosenberg Paul A.
Published: May 2004

Adenosine is an important regulator of neuronal excitability. Zaprinast is a cyclic nucleotide phosphodiesterase inhibitor, and has been shown in the hippocampal slice to suppress excitation. This action can be blocked by an adenosine receptor antagonist, and therefore is presumably due to adenosine release stimulated by exposure to zaprinast. To explore the mechanism of this phenomenon further, we examined the effect of zaprinast on adenosine release itself in cultured rat forebrain neurons. Zaprinast significantly stimulated extracellular adenosine accumulation. The effect of zaprinast on adenosine appeared to be mediated by increasing intracellular cyclic adenosine monophosphate (cAMP) and activation of protein kinase A (PKA): (i) zaprinast stimulated intracellular cAMP accumulation; (ii) a cAMP antagonist (Rp‐8‐Br‐cAMP) significantly reduced the zaprinast effect on adenosine; (iii) an inhibitor of phosphodiesterase (PDE)1 (vinpocetine) and an activator of adenylate cyclase (forskolin) mimicked the effect of zaprinast on adenosine. We also found that zaprinast had no effect on adenosine in astrocyte cultures, and tetrodotoxin completely blocked zaprinast‐evoked adenosine accumulation in neuronal cultures, suggesting that neuronal activity was likely to be involved. Consistent with a dependence on neuronal activity, NMDA receptor antagonists (MK‐801 and D‐APV) and removal of extracellular glutamate by glutamate–pyruvate transaminase blocked the effect of zaprinast. In addition, zaprinast was shown to stimulate glutamate release. Thus, our data suggest that zaprinast‐evoked adenosine accumulation is likely to be mediated by stimulation of glutamate release by a cAMP‐ and PKA‐dependent mechanism, most likely by inhibition of PDE1 in neurons. Furthermore, regulation of cAMP, either by inhibiting cAMP–PDE activity or by stimulating adenylate cyclase activity, may play an important role in modulating neuronal excitability. These data suggest the existence of a homeostatic negative feedback loop in which increases in neuronal activity are damped by release of adenosine following activation of glutamate receptors.
Making a Life Worth Living
Authors: Urry Heather L. , Nitschke Jack B. , Dolski Isa , Jackson Daren C. , Dalton Kim M. , Mueller Corrina J. , Rosenkranz Melissa A. , Ryff Carol D. , Singer Burton H. , Davidson Richard J.
Published: May 2004

Despite the vast literature that has implicated asymmetric activation of the prefrontal cortex in approach-withdrawal motivation and emotion, no published reports have directly explored the neural correlates of well-being. Eighty-four right-handed adults (ages 57–60) completed self-report measures of eudaimonic well-being, hedonic well-being, and positive affect prior to resting electroencephalography. As hypothesized, greater left than right superior frontal activation was associated with higher levels of both forms of well-being. Hemisphere-specific analyses documented the importance of goal-directed approach tendencies beyond those captured by approach-related positive affect for eudaimonic but not for hedonic well-being. Appropriately engaging sources of appetitive motivation, characteristic of higher left than right baseline levels of prefrontal activation, may encourage the experience of well-being.
Scholastic Assessment or g?
Authors: Frey Meredith C. , Detterman Douglas K.
Published: May 2004

There is little evidence showing the relationship between the Scholastic Assessment Test (SAT) and g (general intelligence). This research established the relationship between SAT and g, as well as the appropriateness of the SAT as a measure of g, and examined the SAT as a premorbid measure of intelligence. In Study 1, we used the National Longitudinal Survey of Youth 1979. Measures of g were extracted from the Armed Services Vocational Aptitude Battery and correlated with SAT scores of 917 participants. The resulting correlation was .82 (.86 corrected for nonlinearity). Study 2 investigated the correlation between revised and recentered SAT scores and scores on the Raven's Advanced Progressive Matrices among 104 undergraduates. The resulting correlation was .483 (.72 corrected for restricted range). These studies indicate that the SAT is mainly a test of g. We provide equations for converting SAT scores to estimated IQs; such conversion could be useful for estimating premorbid IQ or conducting individual difference research with college students.
Can a Nonspecific Bias Toward Top-Heavy Patterns Explain Newborns' Face Preference?
Authors: Viola Macchi Cassia , Turati Chiara , Simion Francesca
Published: May 2004

This study examined newborns' face preference using images of natural and scrambled faces in which the location of the inner features was distorted. The results demonstrate that newborns' face preference is not confined to schematic configurations, but can be obtained also with veridical faces. Moreover, this phenomenon is not produced by a specific bias toward the face geometry, but derives from a domain-general bias toward configurations with more elements in the upper than in the lower half (i.e., top-heavy patterns). These results suggest that it may be unnecessary to assume the existence of a prewired tendency to orient toward the face geometry, and support the idea that faces do not possess a special status in newborns' visual world.
When Children Ask, “What Is It?” What Do They Want to Know About Artifacts?
Authors: Deborah G. Kemler Nelson , Louisa Chan Egan , Holt Morghan B.
Published: May 2004

When children ask, “What is it?” are they seeking information about what something is called or what kind of thing it is? To find out, we gave 2-, 3-, and 4-year-olds (32 at each age) the opportunity to inquire about unfamiliar artifacts. An ambiguous question was answered with a name or with functional information, depending on the group to which the children were assigned. Children were inclined to follow up with additional questions about the object when they had been told its name, but seemed satisfied with the answer when they had been told the object's function. Moreover, children in the name condition tended to substitute questions about function for ambiguous questions over the course of the session. These results indicate that children are motivated to discover what kinds of things novel artifacts are, and that young children, like adults, conceive of artifact kinds in terms of their functions.
Functional Magnetic Resonance Imaging Provides New Constraints on Theories of the Psychological Refractory Period
Authors: Jiang Yuhong , Saxe Rebecca , Kanwisher Nancy
Published: May 2004

We used functional magnetic resonance imaging (fMRI) to investigate the psychological refractory period (PRP), the delay in the response to the second of two tasks occurring in immediate succession. Our results were consistent with prior work on the PRP in that when two visual-manual tasks were presented within 100 ms of each other, the second response was delayed on the order of 500 ms, compared with when the two tasks were separated by 1,500 ms. Surprisingly, in brain regions postulated to be important for executive functions, there was virtually no increase in brain activation in the short-interval compared with the long-interval condition. These data suggest that passive queuing, rather than active monitoring, occurs during the PRP.
Use of Cognitive Versus Perceptual Heading During Imagined Locomotion Depends on the Response Mode
Authors: Avraamides Marios N. , Klatzky Roberta L. , Loomis Jack M. , Golledge Reginald G.
Published: May 2004

Three experiments investigated whether the systematic errors previously observed in a triangle-completion task were caused by failures to form and update a cognitive heading or by use of perceived heading (even though an updated cognitive heading was available) during the response. These errors were replicated when participants indicated the origin of triangular paths they had imagined walking by turning their bodies toward the origin, but not when they responded verbally. The results indicate that participants are capable of updating their cognitive heading using imagined movements and suggest that the systematic errors previously observed were a result of the strong attachment of responses such as turns to a perceptual representation of the physical body.
Is Syntax Separate or Shared Between Languages?
Authors: Hartsuiker Robert J. , Pickering Martin J. , Veltkamp Eline
Published: May 2004

Much research in bilingualism has addressed the question of the extent to which lexical information is shared between languages. The present study investigated whether syntactic information is shared by testing if syntactic priming occurs between languages. Spanish-English bilingual participants described cards to each other in a dialogue game. We found that a participant who had just heard a sentence in Spanish tended to use the same type of sentence when describing the next card in English. In particular, English passives were considerably more common following a Spanish passive than otherwise. We use the results to extend current models of the representation of grammatical information to bilinguals.
Using Pointing and Describing to Achieve Joint Focus of Attention in Dialogue
Authors: Bangerter Adrian
Published: May 2004

Pointing was shown to focus attention in dialogue. Pairs of people talked and gestured to identify targets from arrays visible to both of them. Arrays were located at five distances: arm length (0 cm), 25 cm, 50 cm, 75 cm, and 100 cm. Some pairs could point; others could not. People relied more on pointing and less on language as distance decreased. Pointing especially suppressed descriptions of target location, suggesting that it was used to focus attention on a spatial region.
Does Action Make the Link Between Number and Space Representation?
Authors: Rossetti Y. , Jacquin-Courtois S. , Rode G. , Ota H. , Michel C. , Boisson D.
Published: May 2004

If the visual world is artificially shifted by only 10°, people initially experience difficulty in directing their actions toward visual goals, but then rapidly compensate the visual distortion. The consequence of such adaptation can be measured as visual and proprioceptive aftereffects, as well as by performance on pointing tasks without visual feedback. Recent work has shown that more cognitive deficits can be improved following prism adaptation in patients with unilateral neglect. Here we show that a short visuo-manual adaptation to prisms improves performance on a mental number-bisection task recently shown to be impaired in unilateral neglect. The association previously found between space and number representation (the mental number line) may thus be grounded in common action principles. Our results suggest that visuo-motor plasticity functionally links parietal areas involved in space and number representation.
Microsaccades Keep the Eyes' Balance During Fixation
Authors: Engbert Ralf , Kliegl Reinhold
Published: May 2004

During fixation of a stationary target, small involuntary eye movements exhibit an erratic trajectory—a random walk. Two types of these fixational eye movements are drift and microsaccades (small-amplitude saccades). We investigated fixational eye movements and binocular coordination using a statistical analysis that had previously been applied to human posture control. This random-walk analysis uncovered two different time scales in fixational eye movements and identified specific functions for microsaccades. On a short time scale, microsaccades enhanced perception by increasing fixation errors. On a long time scale, microsaccades reduced fixation errors and binocular disparity (relative to pure drift movements). Thus, our findings clarify the role of oculomotor processes during fixation.