bluuebunny/crossref_metadata_2025 huggingface dataset:
Constraint equations between the wheelset and rails on straight railway track
Authors: Lou P
Published: November 2004

The rolling angle and the vertical displacement of the centre of gravity of the wheelset are not independent degrees of freedom while the wheelset runs on railway track. On straight track, the effects of the lateral displacement of the wheelset, of the lateral and vertical displacements of the neutral axis of the left and right rails, of roll around the centre roll of the left and right rails, of the longitudinal profile and lateral alignment irregularities of the left and right rails, and of the conicity of the left and right wheel treads on the rolling angle and the vertical displacement of the centre of gravity of the wheelset are considered in this paper. A generalized spatial rail beam element is presented. The finite element forms of the constraint equations for rolling angle, rolling angular velocity, rolling angular acceleration, vertical displacement, vertical velocity and vertical acceleration of the centre of gravity of the wheelset are expressed by the dependent factors mentioned above. These equations can be useful in three-dimensional vehicle/track interaction modelling.
Analysis of stability of continuously welded rail track with finite elements
Authors: Lei X , Feng Q
Published: November 2004

A computational model for analysing the stability of continuously welded rail track is developed by means of the finite element method in this paper, in which track panels including rails, ties, rail fastenings and ballast resistances as a whole system and non-linear deformation behaviour of rails under temperature stress are considered. Based on the model, the numerical computational formulae are induced and programmed. Influences of the lateral resistances of the ballast, invalid ties and curved track radius as well as initial flexural deformations on the stability of continuously welded rail track are investigated.
A fault-tolerant architecture for computer-based railway vehicle brake systems
Authors: Johansson R
Published: November 2004

In this paper a computer architecture is presented which is suitable for distributed control systems where fault tolerance is desired. The architecture is designed for implementation mainly with standard components ‘off the shelf’ (COTS). In particular there is only a comparable small device called fault-tolerant communication control (FTCC) that requires extensive redundancy. The FTCC is used to close control loops as tightly to the controlled physical device as possible, gaining from the excess computing capacity that a distributed system offers but at the same time removing the impact of increased fault intensity from an increased number of processing elements.

The architecture is preferable for applications where there is some kind of natural inherent redundancy. As a starting point, and also as a case, a state-of-the-art brake control system for railway vehicles is considered. Common computer architectures designed to handle safety-critical applications are recaptured and a feasible solution arrived at in the shape of a slightly modified distributed architecture. This revised distributed architecture is then applied and a revised brake control system is described.

The FTCC device has been implemented, but without redundancy, with standard VHDL (very high speed integrated circuit hardware description language) tools and tested in a simulator environment. Results are promising and indicate that the FTCC device has a great potential in future ‘control-by-wire’ designs.
Growth of multiple rolling contact fatigue cracks driven by rail bending modelled using a boundary element technique
Authors: Fletcher D I , Hyde P , Kapoor A
Published: November 2004

Examination of rails on which large rolling contact fatigue cracks have developed, either at the gauge corner or on the rail head, typically reveals that the cracks have not developed in isolation but occur at intervals along a length of track. Individual cracks are typically separated from one another by a few millimetres, although the reasons for this spacing between the cracks are not yet understood.

This paper presents an investigation into the interaction between adjacent long cracks (tens of millimetres) that are at the beginning of their bending-stress-driven propagation phase. Results are presented as plots of stress intensity factor around crack fronts for single- and multiple-crack situations, for which crack growth rates are predicted. The work focuses particularly on the degree to which single-crack models may be misleading when dealing with a rail containing multiple cracks. The work has application in improving the modelling of crack growth in rails, leading to improved asset management and risk assessment.
Heat convection and design of brake discs
Authors: Sakamoto H
Published: November 2004

An evaluation method of heat convection from brake discs using analytical and experimental approaches is described. Brake discs may be wheel or axle mounted and either ventilated or solid. The majority of brake discs are the ventilated type because of the cooling effect of the fins. In this study, the cooling efficiency of ventilated discs was investigated through the basic equation for heat convection, brake tests and measurements of the flow volume through the fins.

It is concluded that a cooling rate parameter α [= (heat convection × convection area)/(specific heat × disc mass)] derived from the basic equation for heat convection can express the cooling efficiency of a disc. The parameter α can also be used to estimate the maximum temperature accumulated in a disc after several cycles of braking to a stop. As for the design of the brake discs, the heat convection area is more important than the thickness or number of fins. Also the air velocity through the fins should be taken into consideration.
Archaea recruited d-Tyr-tRNATyrdeacylase for editing in Thr–tRNA synthetase
Authors: RIGDEN DANIEL J.
Published: November 2004

Aminoacyl–tRNA synthetases (AARSs) are key players in the maintenance of the genetic code through correct pairing of amino acids with their cognate tRNA molecules. To this end, some AARSs, as well as seeking to recognize the correct amino acid during synthesis of aminoacyl–tRNA, enhance specificity through recognition of mischarged aminoacyl–tRNA molecules in a separate editing reaction. Recently, an editing domain, of uncertain provenance, idiosyncratic to some archaeal ThrRSs has been characterized. Here, sequence analyses and molecular modeling are reported that clearly show a relationship of the archaea-specific ThrRS editing domains withd-Tyr-tRNATyrdeacylases (DTDs). The model enables the identification of the catalytic site and other substrate binding residues, as well as the proposal of a likely catalytic mechanism. Interestingly, typical DTD sequences, common in bacteria and eukaryotes, are entirely absent in archaea, consistent with an evolutionary scheme in which DTD was co-opted to serve as a ThrRS editing domain in archaea soon after their divergence from eukaryotes. A group of present-day archaebacteria contain a ThrRS obtained from a bacterium by horizontal gene transfer. In some of these cases a vestigial version of the original archaeal ThrRS, of potentially novel function, is maintained.
Assembly of the 30S ribosomal subunit: Positioning ribosomal protein S13 in the S7 assembly branch
Authors: GRONDEK JOEL F. , CULVER GLORIA M.
Published: November 2004

Studies of Escherichia coli 30S ribosomal subunit assembly have revealed a hierarchical and cooperative association of ribosomal proteins with 16S ribosomal RNA; these results have been used to compile an in vitro 30S subunit assembly map. In single protein addition and omission studies, ribosomal protein S13 was shown to be dependent on the prior association of ribosomal protein S20 for binding to the ribonucleoprotein particle. While the overwhelming majority of interactions revealed in the assembly map are consistent with additional data, the dependency of S13 on S20 is not. Structural studies position S13 in the head of the 30S subunit > 100 Å away from S20, which resides near the bottom of the body of the 30S subunit. All of the proteins that reside in the head of the 30S subunit, except S13, have been shown to be part of the S7 assembly branch, that is, they all depend on S7 for association with the assembling 30S subunit. Given these observations, the assembly requirements for S13 were investigated using base-specific chemical footprinting and primer extension analysis. These studies reveal that S13 can bind to 16S rRNA in the presence of S7, but not S20. Additionally, interaction between S13 and other members of the S7 assembly branch have been observed. These results link S13 to the 3′ major domain family of proteins, and the S7 assembly branch, placing S13 in a new location in the 30S subunit assembly map where its position is in accordance with much biochemical and structural data.
The RNA catabolic enzymes Rex4p, Rnt1p, and Dbr1p show genetic interaction with trans-acting factors involved in processing of ITS1 in Saccharomyces cerevisiae pre-rRNA
Authors: FABER ALEX W. , VOS JAN C. , VOS HARMJAN R. , GHAZAL GHADA , ABOU ELELA SHERIF , RAUÉ HENDRIK A.
Published: November 2004

Eukaryotes have two types of ribosomes containing either 5.8SL or 5.8SS rRNA that are produced by alternative pre-rRNA processing. The exact processing pathway for the minor 5.8SL rRNA species is poorly documented. We have previously shown that the trans-acting factor Rrp5p and the RNA exonuclease Rex4p genetically interact to influence the ratio between the two forms of 5.8S rRNA in the yeast Saccharomyces cerevisiae. Here we report a further analysis of ITS1 processing in various yeast mutants that reveals genetic interactions between, on the one hand, Rrp5p and RNase MRP, the endonuclease required for 5.8SS rRNA synthesis, and, on the other, Rex4p, the RNase III homolog Rnt1p, and the debranching enzyme Dbr1p. Yeast cells carrying a temperature-sensitive mutation in RNase MRP (rrp2-1) exhibit a pre-rRNA processing phenotype very similar to that of the previously studied rrp5-33 mutant: ITS2 processing precedes ITS1 processing, 5.8SL rRNA becomes the major species, and ITS1 is processed at the recently reported novel site A4 located midway between sites A2 and A3. As in the rrp5-Δ3 mutant, all of these phenotypical processing features disappear upon inactivation of the REX4 gene. Moreover, inactivation of the DBR1 gene in rrp2-1, or the RNT1 gene in rrp5-Δ3 mutant cells also negates the effects of the original mutation on pre-rRNA processing. These data link a total of three RNA catabolic enzymes, Rex4p, Rnt1p, and Dbr1p, to ITS1 processing and the relative production of 5.8SS and 5.8SL rRNA. A possible model for the indirect involvement of the three enzymes in yeast pre-rRNA processing is discussed.
Generation of a catalytic module on a self-folding RNA
Authors: YOSHIOKA WATARU , IKAWA YOSHIYA , JAEGER LUC , SHIRAISHI HIDEAKI , INOUE TAN
Published: November 2004

It is theoretically possible to obtain a catalytic site of an artificial ribozyme from a random sequence consisting of a limited numbers of nucleotides. However, this strategy has been inadequately explored. Here, we report an in vitro selection technique that exploits modular construction of a structurally constrained RNA to acquire a catalytic site for RNA ligation from a short random sequence. To practice the selection, a sequence of 30 nucleotides was located close to the putative reaction site in a derivative of a naturally occurring self-folding RNA whose crystal structure is known. RNAs whose activity depended on the starting three-dimensional structure were selected with 3′–5′ ligation specificity, indicating that the strategy can be used to acquire a variety of catalytic sites and other functional RNA modules.
Development and preliminary validation of the Glasgow Content of Thoughts Inventory (GCTI): A new measure for the assessment of pre‐sleep cognitive activity
Authors: Harvey Karen J. , Espie Colin A.
Published: November 2004

Objective: To develop a self‐report measure (the Glasgow Content of Thoughts Inventory [GCTI]) for the assessment of pre‐sleep cognitive activity in adults with sleep‐onset insomnia.

Design: A psychometric, scale development approach was used.

Method: Over three consecutive nights, 12 people with insomnia provided ‘live’ audio‐recordings of pre‐sleep thought content, which were used to generate an item pool. The results were compared to the content and categorical structure of pre‐sleep cognitive activity identified by Wicklow and Espie (2000), and commonalities in thought content were used to generate a draft scale. Following further piloting, a 25‐item scale was developed and administered to two groups (29 people with insomnia and 29 good sleepers), along with other self‐report measures, objective (actigraphic recordings) and subjective (diary) sleep indices, and results analysed to evaluate the psychometric properties of the scale.

Results: The GCTI demonstrated evidence of construct validity, successfully discriminated between individuals with insomnia and good sleepers, and was significantly correlated with existing measures of sleep disturbance. A score of 42 yielded a sensitivity of 100% and specificity of 83%. The GCTI demonstrated good test– retest reliability (ICC = .88) and internal consistency (α = .87).

Conclusions: The GCTI appears to be a valid and reliable instrument for use with patients with sleep‐onset insomnia.
Illness representations in depression
Authors: Fortune Gillian , Barrowclough Christine , Lobban Fiona
Published: November 2004

Background and objectives: Illness representations in physical health problems have been studied extensively using the Self‐regulation Model (SRM) focusing on five dimensions of illness beliefs (identity, consequences, causes, timeline and control, or cure). Associations have been found between beliefs about illness and a range of health outcomes. This study aimed to examine models of depression, to assess whether the five dimensions of the SRM are relevant, to compare depression models with those for physical illness, and to examine the psychometric properties of the Illness Perception Questionnaire (IPQ) when used with depression.

Design and method: A sample of 101 women either currently depressed or with a history of depression was asked to write about their experiences of physical sickness and depression. Their responses were analysed in terms of the dimensions of beliefs expressed and the two experiences were compared. The IPQ was also administered to assess the women's perceptions of depression.

Results: The women used the same five dimensions of illness as identified in the SRM in describing both their experience of depression and physical sickness. There was evidence of some consistency across the models of the two illnesses in terms of their content and structure. The IPQ was a reliable measure for depressed experiences and discriminated between women who were currently depressed or not. Comparing the women's descriptions of their depression with their IPQ scores showed some relationships between their responses on the two different measures, at least for the consequences and cause dimensions.

Conclusion: The SRM model and associated methodology may provide an appropriate framework to further explore illness representations in depression. Problems inherent in the study of illness models in depression including the influence of mood on the model are described. Applications of this research area to the understanding of treatment preferences and adherence to treatment in mood disorders are discussed.
Parent training for Attention Deficit/Hyperactivity Disorder: Is it as effective when delivered as routine rather than as specialist care?
Authors: Sonuga‐Barke Edmund J.S. , Thompson Margaret , Daley David , Laver‐Bradbury Cathy
Published: November 2004

Background: The effectiveness of parent training (PT) when delivered as part of specialist tier‐two services for preschool AD/HD children has been recently demonstrated.

Aims: To assess the effectiveness of the same PT programme when delivered as part of routine primary care by non‐specialist nurses.

Method: A sample of 89 3‐year‐old children with preschool AD/HD took part in a controlled trial of an eight‐week (one hour a week), health visitor delivered, PT package. Children, allocated randomly to PT (n = 59) and waiting list control (WLC; n = 30) groups, were compared.

Results: PT did not reduce AD/HD symptoms. Maternal well‐being decreased in both PT and WLC groups.

Conclusions: While PT is an effective intervention for preschool AD/HD when delivered in specialized settings, these benefits do not appear to generalize when programme are delivered as part of routine primary care by non‐specialist nurses.
Crash Test Dummies? The Impact of Televised Automotive Crash Tests on Vehicle Sales and Securities Markets
Authors: Pruitt Stephen W. , Hoffer George E.
Published: November 2004

Broadcasts of Insurance Institute for Highway Safety high-speed automotive crash tests on NBC's Dateline do not affect either market shares or stock prices. However, injury claims within a market class are highly correlated with crash test ratings. Inattention to the tests may be a consequence of the manner in which the crash tests have been presented and because the crashworthiness of the U.S. vehicle fleet is positively correlated with consumer estimates of expected vehicle safety.
Integrating Public Policy and Public Affairs in a Pharmaceutical Marketing Program: The AIDS Pandemic
Authors: Kennedy Charles R. , Harris Frederick H.deB. , Lord Michael
Published: November 2004

The pharmaceutical industry's traditional business model is under severe strain as a result of differential pricing and global threats to intellectual property protection. An integrative marketing program of public relations and public policy initiatives, in conjunction with key stakeholders, could motivate the creation of necessary incentives for the discovery of crucial new AIDS drugs and their delivery to global markets.
Adherence of Prime-Time Televised Advertising Disclosures to the “Clear and Conspicuous” Standard: 1990 versus 2002
Authors: Hoy Mariea Grubbs , Andrews J. Craig
Published: November 2004

In 1990, one-fourth of all national television commercials contained disclosures, yet none of the disclosures adhered to all of the Federal Trade Commission's “clear and conspicuous” standard (CCS). As a result of marketplace changes and a 2001 Federal Trade Commission and National Advertising Division joint workshop, the authors anticipate an increase in the number of disclosures and greater adherence to the CCS. The authors find a significant increase in disclosure incidence; however, adherence declines or remains unchanged for most individual guidelines. Finally, the authors provide public policy implications and offer suggestions to increase adherence to the CCS.
The Legalization of Internet Gambling: A Consumer Protection Perspective
Authors: Watson Stevie , Liddell Pearson , Moore Robert S. , Eshee William D.
Published: November 2004

The complexities of Internet gambling limit congressional efforts to regulate its growth. Therefore, legislative attempts to prohibit Internet gaming may undermine the protection mechanisms that were designed to help people who are susceptible to the social and economic problems linked to gambling. The authors suggest that congressional efforts to prohibit Internet gambling should be reassessed, and they recommend the legalization and regulation of Internet gambling through existing land-based casinos. Finally, the authors present the regulatory guidelines and cooperative policy initiatives that are necessary for such a proposition.
The Future of Online Gambling in the United States and Elsewhere
Authors: Eadington William R.
Published: November 2004

This article examines the current economic characteristics of online gambling and the implications of current U.S. policies to prohibit its emergence. The author discusses online gambling's fundamental economic, political, and legal dimensions, as well as its current institutional setting. The present U.S. strategy is intended to marginalize online gambling, purportedly because of concerns about adverse social impacts. However, because of actions abroad to create legal regulatory regimes to govern online gambling, and because the Internet is becoming increasingly worldwide, U.S. attempts to prohibit online gambling are likely to be futile in the long run.
Syntactic theories and syntactic methodology: a reply to Seuren
Authors: CROFT WILLIAM
Published: November 2004

In his review of Radical Construction Grammar: syntactic theory in typological perspective (Croft 2001), Pieter Seuren argues that the theory of syntactic representation argued for in that book is fundamentally misguided. S also raises a number of general methodological and philosophical issues, as well as some empirical data, which he claims are problematic for RCG. I begin by dealing with the general critique, then turn to S's discussion of the specific major theses of RCG and his empirical data.
Childhood sexual abuse, stressful life events and risk for major depression in women
Authors: KENDLER KENNETH S. , KUHN JONATHAN W. , PRESCOTT CAROL A.
Published: November 2004

Background. In animals, early trauma can produce long-lasting changes in sensitivity to the pathogenic effects of stress. To explore whether similar processes occur in humans, we examine whether childhood sexual abuse (CSA) in women alters sensitivity in adulthood to the depressogenic effects of stressful life events (SLEs).

Method. A history of CSA was obtained from a population-based sample of 1404 female adult twins. Cox Proportional hazard models were used to predict onsets of episodes of DSM-III-R major depression (MD) in the past year from previously assessed levels of neuroticism (N), CSA and past-year SLEs scored on long-term contextual threat.

Results. In the best-fit model, onset of MD was predicted by CSA, SLEs and N. Individuals with CSA (and especially with severe CSA) had both an overall increased risk for MD and a substantially increased sensitivity to the depressogenic effects of SLEs. A ‘dose–response’ relationship between severity of CSA and sensitivity to SLEs was clearer in those with low to average levels of N than in those with high levels of N.

Conclusion. As documented with physiological responses to a standardized laboratory stressor, CSA increases stress sensitivity in women in a more naturalistic setting. Both genetic and early environmental risk factors can produce long-term increase in the sensitivity of individuals to depressogenic life experiences.
Craniological differentiation amongst wild‐living cats in Britain and southern Africa: natural variation or the effects of hybridisation?
Authors: Yamaguchi Nobuyuki , Kitchener Andrew C. , Driscoll Carlos A. , Ward Jennifer M. , Macdonald David W.
Published: November 2004

The natural morphological variation in the wildcat, Felis silvestris, and morphological changes possibly caused by introgressive hybridisation with the domestic cat, F. catus, were examined, based on up to 39 variables concerning cranial morphology. The samples of wild‐living cats originated from Scotland and southern Africa and consisted of both classical wildcat and other pelage types. Principal component and cluster analyses suggested that introgressive hybridisation occurred in both areas, with the consequence that the characteristics of local wildcat populations had been altered in terms of the frequencies of occurrence of certain characters, especially those concerning cranial capacity. In both regions the clustering patterns of wild‐living cats can be interpreted as containing four main groups. One of these consisted mainly of ‘non‐wildcats’ and groups furthest from the ‘non‐wild’ cluster consisted of the highest proportion of ‘wildcats’ (c. 80%). We propose that where a population is heavily introgressed, the only feasible way to define a wildcat is on the basis of inter‐correlated features and conservationists must take a population‐based approach to assess the extent of introgression. This approach may provide an operational standard for assessing the impact of hybridisation between wildcats and domestic cats throughout the species' range; it suggests that the Scottish wildcats may be critically endangered.
Having your wildlife and eating it too: an analysis of hunting sustainability across tropical ecosystems
Authors: Robinson John G. , Bennett Elizabeth L.
Published: November 2004

Unsustainable hunting of wildlife or bushmeat for human consumption across the tropics threatens both wildlife populations and the livelihoods of people who depend on these resources. The probability that hunting can be sustainable depends in part on ecological conditions that affect the ‘supply’ of and ‘demand’ for wildlife resources. In this study, supply is estimated across a number of tropical ecosystem types by calculating the theoretical ‘maximum sustainable offtake’ in kg/km2 for harvestable wildlife. Demand is estimated from observed harvests in kg/km2. We examine how supply and demand vary across relatively undisturbed ecosystems, indexed by annual rainfall. Supply is potentially highest in dry forests and wetter savannah grasslands and decreases in moist forests and more xeric grasslands. Demand tends to exceed supply in moist forests and xeric grasslands. Analogous to this ecological variation along the rainfall gradient is the gradient created by the conversion of tropical forests by humans. We hypothesise that the wild meat supply is greater in secondary forests and forest–farm–fallow mosaics than in undisturbed forests and test this with available data. We conclude that the probability that hunting will be sustainable varies with ecosystem type and degree of human disturbance and should influence where land is zoned for protected areas and where for wildlife harvests.
High offspring survival of the brown‐headed cowbird in an invaded habitat
Authors: Winfree Rachael
Published: November 2004

The brood parasitic brown‐headed cowbird (Molothrus ater) is considered an important threat to bird conservation in North America because it reduces the reproduction of its numerous host species. Prior to the colonisation of America by Europeans, the cowbird was largely confined to the North American prairie region, but it has since invaded forests and other habitats and is now one of the continent's most abundant breeding passerines. The objective of this study was to examine cowbird reproduction with different host communities to determine whether habitat‐specific reproduction might contribute to the cowbird's population expansion. Cowbird offspring survival was estimated with hosts breeding in fragmented deciduous forest (a newly invaded habitat) and old fields (a habitat more similar to the cowbird's original range). Offspring survival was 1.8–3.1 times higher in forest compared to old fields and was high enough to cause the cowbird population to increase with most forest hosts. The results suggest that increased offspring survival in an invaded habitat facilitates cowbird population growth. Land management for extensive, continuous forests, which cowbirds are known to avoid, could help control the cowbird population and reduce parasitism levels for the >140 species of cowbird hosts.
Inbreeding depression and founder diversity among captive and free‐living populations of the endangered pink pigeonColumba mayeri
Authors: Swinnerton Kirsty J. , Groombridge Jim J. , Jones Carl G. , Burn Robert W. , Mungroo Yousoof
Published: November 2004

The endemic pink pigeon has recovered from less than 20 birds in the mid‐1970s to 355 free‐living individuals in 2003. A major concern for the species' recovery has been the potential genetic problem of inbreeding. Captive pink pigeons bred for reintroduction were managed to maximise founder representation and minimise inbreeding. In this paper, we quantify the effect of inbreeding on survival and reproductive parameters in captive and wild populations and quantify DNA sequence variation in the mitochondrial d‐loop region for pink pigeon founders. Inbreeding affected egg fertility, squab, juvenile and adult survival, but effects were strongest in highly inbred birds (F≥0.25). Inbreeding depression was more apparent in free‐living birds where even moderate levels of inbreeding affected survival, although highly inbred birds were equally compromised in both captive and wild populations. Mitochondrial DNA haplotypic diversity in pink pigeon founders is low, suggesting that background inbreeding is contributing to low fertility and depressed productivity in this species, as well as comparable survival of some groups of non‐inbred and nominally inbred birds. Management of wild populations has boosted population growth and may be required long‐term to offset the negative effects of inbreeding depression and enhance the species' survival.
Conservation significance of island versus mainland populations: a case study of dibblers (Parantechinus apicalis) in Western Australia
Authors: Mills Harriet R. , Moro Dorian , Spencer Peter B. S.
Published: November 2004

Island populations are an interesting dichotomy in conservation biology. On the one hand, they can be a refuge for species where mainland populations have been decimated by loss of habitat and predation by exotic predators. On the other hand, island populations usually have reduced genetic diversity and are more susceptible to extinction through genetic and demographic processes. Genetic variation and morphological characters were measured for island and mainland populations of Parantechinus apicalis, small dasyurid marsupials, restricted to southwest Australia. Genetic variation at seven microsatellite loci revealed low levels of heterozygosity (He= 0.20−0.44) and high levels of inbreeding (Fe= 0.40−0.72) in island populations compared with the mainland population (He= 0.73). A nested clade analysis revealed that allopatric fragmentation was probably responsible for the association between geographical location and control region haplotypes, which is consistent with the isolation of populations on islands and indicative of two main populations of P. apicalis representing separate conservation units for management. While these results are typical of many island populations, they have important implications in terms of the conservation of threatened species in Australia and around the world, where island populations are a common source of founders for captive breeding and translocation to mainland sites.
Determination of ape distribution and population size using ground and aerial surveys: a case study with orang‐utans in lower Kinabatangan, Sabah, Malaysia
Authors: Ancrenaz Marc , Goossens Benoit , Gimenez Olivier , Sawang Azri , Lackman‐Ancrenaz Isabelle
Published: November 2004

Because of the difficulties encountered in detecting many large tropical forest‐dwelling species in their natural habitat, precise figures concerning the distribution, number and trends of many populations remain deficient. In tropical forests, ground surveys are generally carried out by counting objects along straight lines. These counts require a strict compliance with the line‐transect methodology before (proper design of the census), during (careful data collection) and after (accurate and correct data processing and analysis) the census itself. In addition, the major source of bias when estimating population size and/or trends comes from the extrapolation of estimates obtained in small sampling areas to the larger, and often incompletely known, distribution of the population. In the Kinabatangan floodplain (Sabah, Malaysia), helicopter surveys were useful in directly assessing the distribution of orang‐utans and were a major advantage in the precise estimation of the size of the orang‐utan population surviving in this region. Our survey showed that about 1100 orang‐utans remain in the multiple‐use forests of the Kinabatangan floodplain. These results provide new evidence on orang‐utan adaptation to habitat disturbance and indicate the potential of the Kinabatangan multiple‐use forests for orang‐utan conservation. Helicopter surveys appear to be a promising alternative to ground survey for precise distribution assessment and for monitoring population trends of apes throughout their entire range in Asia and in some parts of Africa.
Unsustainable harvest of dugongs in Torres Strait and Cape York (Australia) waters: two case studies using population viability analysis
Authors: Heinsohn Robert , Lacy Robert C. , Lindenmayer David B. , Marsh Helene , Kwan Donna , Lawler Ivan R.
Published: November 2004

A significant proportion of the world's remaining dugongs (Dugong dugon) occur off northern Australia where they face various anthropogenic impacts. Here, we investigate the viability of two dugong meta‐populations under varying regimes of indigenous hunting. We construct population viability analyses (PVAs) using the computer package VORTEX and published estimates of population sizes and hunting rates. In Torres Strait between Cape York and New Guinea, our models predict severe and imminent reductions in dugong numbers. Our ‘optimistic’ and ‘pessimistic’ models suggest median times for quasi‐extinction of 123 and 42 years, respectively. Extinction probabilities are also high for eastern Cape York Peninsula. We demonstrate the inadequacy of reserves when harvest rates in neighbouring areas are high, identify the maximum harvest rates for meta‐population stability and emphasise the urgent need for indigenous community involvement in management to establish sustainable rates of dugong harvest in these regions.
Aerial surveys and the potential biological removal technique indicate that the Torres Strait dugong fishery is unsustainable
Authors: Marsh Helene , Lawler Ivan R. , Kwan Donna , Delean Steve , Pollock Kenneth , Alldredge Matthew
Published: November 2004

The globally significant dugong population of Torres Strait supports an important indigenous fishery for meat and oil. The fishery is protected by the Torres Strait Treaty between Australia and Papua New Guinea. A time series of aerial survey estimates from 1987–2001 confirms that there is considerable temporal variability in the size of the dugong population in the region and adds to a growing body of evidence from other aerial surveys and satellite tracking that dugongs undertake large‐scale movements associated with temporal and spatial changes in the distribution of their seagrass food. The magnitude of these effects on both the size of the population and the catch cannot be disaggregated from the effects of population depletion from over‐harvesting. The Potential Biological Removal method was used in conjunction with the aerial survey data to estimate sustainable anthropogenic mortality from all causes for a range of empirically‐derived estimates of dugong life‐history parameters. These estimates of a sustainable harvest are so far below the current harvest that it must be unsustainable. Governments should heed the Islanders' requests for assistance in implementing co‐management of the fishery as a matter of urgency.
Are introduced and re‐introduced species comparable? A case study of birds
Authors: Blackburn Tim M. , Cassey Phillip
Published: November 2004

Knowledge of the causes of success or failure in introductions may provide information to help improve the chances that re‐introductions succeed. However, the utility of this information will be influenced by the comparability of sets of introduced and re‐introduced species. Here, we assess the extent of this similarity using recent historical data on introduced and re‐introduced birds. Introductions are less often threatened than expected and have larger ranges and earlier ages at maturity than re‐introductions. Introductions also generally have ‘weedy’ life‐history characteristics relative to family‐typical values, whereas those of re‐introductions more closely conform to these typical values. However, introductions and re‐introductions do not differ in migratory behaviour, mating system or dichromatism, nor do they show statistically consistent differences in body mass, incubation time or annual fecundity. The taxonomic composition of the lists of introductions and re‐introductions is similar, with more species than expected on both lists. Overall, these results suggest that the characteristics of introductions and re‐introductions are sufficiently similar that conclusions from studies of the former may reasonably be used to inform studies of the latter.
Ion temperature crests and troughs in the morning sector of the low‐latitude and midlatitude topside ionosphere
Authors: Chao C. K. , Su S.‐Y. , Yeh H. C.
Published: November 2004

The low‐latitude and midlatitude topside ionospheric ion temperature at 600 km altitude has been measured with the Ionospheric Plasma and Electrodynamics Instrument (IPEI) instrument on board ROCSAT‐1 satellite in the solar maximum year of 2000. Global hemispheric asymmetrical distribution of this topside ion temperature in the morning hour is presented here for the first time and is explained with the associated observation of the field‐aligned ion flow and ion concentration. Crests of ion temperature are found along the dip latitudes between 10° and 25° in the winter hemisphere during the solstice seasons. The maximum in the temperature crests is located in a longitudinal region of positive magnetic declination in the southern hemisphere during the June solstice and in the longitudinal region of negative magnetic declination in the northern hemisphere during the December solstice. Ion compression from a downward field‐aligned ion flow driven by morning neutral wind is concluded to cause the ion heating in the winter hemisphere as modeled by Bailey et al. [1975]. On the other hand, in the 0700–0800 LT sector, there are low‐temperature regions at higher latitudes in a longitude region of negative magnetic declination in the southern hemisphere during the June solstice and in the longitudinal region of positive magnetic declination in the northern hemisphere during the December solstice. A low photoionization rate together with an ion expansion cooling process from the upward field‐aligned plasma flow has resulted in such low temperature in these regions. As for temperature troughs observed near the dip equator in the morning hour, it is attributed to the convective heat loss in the summer hemisphere initially in the early morning hour and then to the rapid increase of plasma concentration at the dip equator in the late morning hour for all seasons.
Multidimensional density operator propagations in open systems: Model studies on vibrational relaxations and surface sticking processes
Authors: Cattarius Christoph , Meyer Hans-Dieter
Published: November 2004

An efficient method for the numerical treatment of multidimensional dynamics of open systems is presented: the multiconfiguration time-dependent Hartree (MCTDH) method extended to the propagation of density operators. With this method we investigate the relaxation process of a CO molecule adsorbed on a copper surface, i.e., CO/Cu(100), after the excitation with an infrared (IR) pulse. The interaction potential was taken from the literature [J. C. Tully and M. Gomez, J. Vac. Sci. Technol. A 11, 1914 (1993)]. Lifetime estimations and thermalization studies were performed on the IR excited CO molecule. We were able to treat this system with all six degrees of freedom (DOF) and thus 12 dynamical variables, but most of our studies used a two or four DOF model. Finally, we demonstrate the applicability of MCTDH to the analysis of scattering processes in an open environment. We calculate sticking coefficients of a scattered particle to a model surface, the latter acting as heat bath. The surface corrugation and the initial particle energy have been varied, and six different relaxation strengths have been studied. These calculations were done under the inclusion of three DOFs: the two surface coordinates and the distance between the particle and the surface.
Oral candidiasis and nutritional deficiencies in elderly hospitalised patients
Authors: Paillaud Elena , Merlier Isabelle , Dupeyron Catherine , Scherman Elisabeth , Poupon Joël , Bories Phuong-Nhi
Published: November 2004

The prevalence of oral candidiasis and its association with malnutrition in terms of protein–energy malnutrition and mineral and vitamin depletion were evaluated in ninety-seven hospitalised older adults aged 82·1 (SD 8·6) years. Patients underwent a complete oral examination with microbiological investigation on admission to our geriatric rehabilitation unit. Patients were assessed nutritionally by evaluation of dietary intake and measurement of anthropometric variables, serum nutritional proteins, ferritin, Zn, folate, vitamins B12 and C. The prevalence of oral candidiasis was 37% (n 36); the proportion of patients with BMI <20 kg/m2 was 32% (n 31). The nutritional status of the population was studied by comparing two groups defined according to the absence (group I; n 61) or presence (group II; n 36) of oral candidiasis. The two groups did not differ on the basis of BMI and mid-arm circumference. However, group II had a smaller leg circumference, lower daily energy and protein intakes, lower albumin and transthyretin levels. Patients successfully treated with fluconazole increased their intake on day 30. The proportion of patients with hypozincaemia (<12·5 μmol/l) and vitamin C deficiency (<0·7 mg/l) was higher in group II. Treatment with antibiotics, poor oral hygiene, denture wearing, and vitamin C deficiency appeared as the most significant independent risk factors associated with oral candidiasis. The present findings show that oral candidiasis appears to be related to malnutrition and results in mucosal lesions that have a negative impact on energy intake, which may subsequently worsen nutritional status.
Maternal body composition, HIV infection and other predictors of gestation length and birth size in Zimbabwe
Authors: Friis Henrik , Gomo Exnevia , Nyazema Norman , Ndhlovu Patricia , Krarup Henrik , Kæstel Pernille , Michaelsen Kim Fleischer
Published: November 2004

The role of maternal infections, nutritional status and obstetric history in low birth weight is not clear. Thus, the objective of the present study was to assess the effects of maternal HIV infection, nutritional status and obstetric history, and season of birth on gestation length and birth size. The study population was 1669 antenatal care attendees in Harare, Zimbabwe. A prospective cohort study was conducted as part of a randomised, controlled trial. Maternal anthropometry, age, gravidity, and HIV status and load were assessed in 22nd–35th weeks gestation. Outcomes were gestation length and birth size. Birth data were available from 1106 (66·3%) women, of which 360 (32·5%) had HIV infection. Mean gestation length was 39·1 weeks with 16·6% <37 weeks, mean birth weight was 3030 g with 10·5% <2500 g. Gestation length increased with age in primigravidae, but not multigravidae (interaction,P=0·005), and birth in the early dry season, low arm fat area, multiple pregnancies and maternal HIV load were negative predictors. Birth weight increased with maternal height, and birth in the late rainy and early dry season; primi-secundigravidity, low arm fat area, HIV load, multiple pregnancies and female sex were negative predictors. In conclusion, gestation length and birth weight decline with increasing maternal HIV load. In addition, season of birth, gravidity, maternal height and body fat mass, and infant sex are predictors of birth weight.
Targeting Anti—Transferrin Receptor Antibody (OX26) and OX26-Conjugated Liposomes to Brain Capillary Endothelial Cells Using In Situ Perfusion
Authors: Gosk Sara , Vermehren Charlotte , Storm Gert , Moos Torben
Published: November 2004

Brain capillary endothelial cells (BCECs) express transferrin receptors. The uptake of a potential drug vector (OX26, or anti—transferrin receptor antibody IgG2a) conjugated to polyethyleneglycol-coated liposomes by BCECs was studied using in situ perfusion in 18-day-old rats in which the uptake of OX26 is almost twice as high as in the adult rat. Using radio-labeling, the uptake of OX26 by BCECs after 15-minute perfusion was approximately 16 times higher than that of nonimmune IgG2a (Ni-IgG2a). OX26 and OX26-conjugated liposomes selectively distributed to BCECs, leaving choroid plexus epithelium, neurons, and glia unlabeled. Ni-IgG2a and unconjugated liposomes did not reveal any labeling of BCECs. The labeling of BCECs by OX26 was profoundly higher than that of transferrin. Perfusion with albumin for 15 minutes did not reveal any labeling of neurons or glia, thus confirming the integrity of the blood—brain barrier. The failure to label neurons and glia shows that OX26 and OX26-conjugated liposomes did not pass through BCECs. The expression of transferrin receptors by endothelial cells selective to the brain qualifies OX26 as a candidate for blood-to-endothelium transport. A specifically designed formulation of liposomes may allow for their degradation within BCECs, leading to subsequent transport of liposomal cargo further into the brain.
Postischemic Intraventricular Administration of FGF-2 Expressing Adenoviral Vectors Improves Neurologic Outcome and Reduces Infarct Volume after Transient Focal Cerebral Ischemia in Rats
Authors: Watanabe Takuji , Okuda Yasuaki , Nonoguchi Naosuke , Zhao Ming Zhu , Kajimoto Yoshinaga , Furutama Daisuke , Yukawa Hiroyuki , Shibata Masa-Aki , Otsuki Yoshinori , Kuroiwa Toshihiko , Miyatake Shin-Ichi
Published: November 2004

Fibroblast growth factor (FGF)-2 is a potent neurotrophic and angiogenic peptide. To examine possible protective effects of FGF-2 gene expression against transient focal cerebral ischemia in rats, a replication defective, recombinant adenovirus vector expressing FGF-2, was injected intraventricularly 2 hours after middle cerebral artery occlusion (MCAO). The treatment group showed significant recovery compared with the vehicle-treated groups in terms of serial neurologic severity scores over the 35 days after MCAO. Further, 2,3,5-triphenyltetrazolium chloride staining showed that FGF-2 gene transfer decreased infarct volume by 44% as compared with that in the vehicle-treated groups at 2 days after MCAO. The same tendency of gene transfer effects on infarct volume was confirmed at 35 days after MCAO with hematoxylin/eosin staining. Enzyme-linked immunosorbent assay revealed that FGF-2 concentration was increased significantly at 2 days after MCAO, not only in cerebrospinal fluid but also in cerebral substance in the lesioned and treated animals. These results suggested that FGF-2 gene transfer using these adenoviral vectors might be a useful modality for the treatment of occlusive cerebrovascular disease even after the onset of stroke.