bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulator Studies on a Collision Avoidance Display that Facilitates Efficient and Precise Assessment of Evasive Manoeuvres in Congested Waterways
Authors: Pedersen Egil , Inoue Kinzo , Tsugane Masanori 
Published: September 2003

This paper is based on two articles by the authors that were published in the March and September 2002 issues of the Journal of Japan Institute of Navigation.The collision risk to multiple targets and identification of feasible evasive manoeuvres can be assessed simultaneously in true motion by judging the tip of own ship's velocity vector in relation to the display of cone-shaped collision danger regions to acquired targets. Simulator test programmes composed of scenarios with various traffic densities and different speed ranges of own ship have been carried out in order to evaluate the performance of this collision avoidance display versus ARPA (true and relative motion) displays. Experienced navigators and maritime university students with license participated as test subjects. It is shown that the proposed display is capable to facilitate more homogeneous, precise and safe evasive manoeuvres than utilising conventional judgement techniques. The superiority increases with the excess speed of own ship, traffic density and complexity.
Altered behaviour in spotted hyenas associated with increased human activity
Authors: Boydston Erin E. , Kapheim Karen M. , Watts Heather E. , Szykman Micaela , Holekamp Kay E. 
Published: September 2003

AbstractTo investigate how anthropogenic activity might affect large carnivores, we studied the behaviour of spotted hyenas (Crocuta crocuta) during two time periods. From 1996 to 1998, we documented the ecological correlates of space utilization patterns exhibited by adult female hyenas defending a territory at the edge of a wildlife reserve in Kenya. Hyenas preferred areas near dense vegetation but appeared to avoid areas containing the greatest abundance of prey, perhaps because these were also the areas of most intensive livestock grazing. We then compared hyena behaviour observed in 1996–98 with that observed several years earlier and found many differences. Female hyenas in 1996–98 were found farther from dens, but closer to dense vegetation and to the edges of their territory, than in 1988–90. Recent females also had larger home ranges, travelled farther between consecutive sightings, and were more nocturnal than in 1988–90. Finally, hyenas occurred in smaller groups in 1996–98 than in 1988–90. We also found several changes in hyena demography between periods. We next attempted to explain differences observed between time periods by testing predictions of hypotheses invoking prey abundance, climate, interactions with lions, tourism and livestock grazing. Our data were consistent with the hypothesis that increased reliance on the reserve for livestock grazing was responsible for observed changes. That behavioural changes were not associated with decreased hyena population density suggests the behavioural plasticity typical of this species may protect it from extinction.
Using artificial neural networks to assess wolf distribution patterns in Portugal
Authors: Bessa‐Gomes Carmen , Petrucci‐Fonseca Francisco 
Published: September 2003

AbstractAlthough the conservation of endangered species often implies the definition of priority areas for conservation, detailed information on their distribution patterns is seldom available over a large geographic range. The present paper explores the performance of an alternative data analysis approach, artificial neural networks, for assessing distribution patterns of endangered mammals when data are scarce and noisy. This approach was applied to identify wolf occupancy in Portugal based on information on wolf depredation and inquiries. Artificial neural networks were able to discriminate successfully between areas sporadically used by vagrant individuals and areas occupied by resident wolves, with a low estimated prediction error (around 1%). Only 33% of the wolf range is regularly occupied, being fragmented in five nuclei. These nuclei are surrounded by more disturbed marginal areas, with a source‐sink dynamic between nucleus and marginal areas. Selection of priority areas for wolf conservation in the context of the Natura 2000 Network increased twofold the proportion of wolf regular range within protected areas. The good performance of artificial neural networks in assessing wolf distribution patterns suggests that this approach may be applied to other species where detailed records of distribution are limited.
Viability of a diminishing roan antelope population: predation is the threat
Authors: McLoughlin Craig A. , Owen‐Smith Norman 
Published: September 2003

AbstractThe roan antelope (Hippotragus equinus) population inhabiting the Kruger National Park, South Africa, declined from 450 animals in 1986 to around 25 free‐ranging animals subsequent to 1994. A computer simulation model was developed to: (1) evaluate likely contributions of low rainfall, habitat deterioration, population fragmentation and predation to the observed population decline; (2) project future likelihood of persistence of the population remnant, under various scenarios. Direct consequences of severe drought and habitat deterioration alone were inadequate to explain the observed decline, unless effects were more severe than assumed in the model. An increased predation loss to around 30% per year was needed. Persistence probability over 50 years was less than 0.5 if the predation loss remained above 20% per year. Models that take into account only stochastic uncertainty in demography and environmental variability are of limited reliability if potential changes in predation risk are not also accommodated.
A recent bottleneck in the warthog and elephant populations of Queen Elizabeth National Park, revealed by a comparative study of four mammalian species in Uganda national parks
Authors: Muwanika Vincent B. , Siegismund Hans R. , Okello John Bosco A. , Masembe Charles , Arctander Peter , Nyakaana Silvester 
Published: September 2003

AbstractUntil 1972, Uganda's national parks boasted of large numbers of large mammal species. Following the breakdown of law and order between 1972 and 1985, large‐scale poaching led to an unprecedented decline in numbers of most large mammals in Uganda's national parks. However, the extent of decline varied in the different parks across different animal species. We have investigated the genetic effects of these reductions in four mammalian species (the common warthog, African savannah elephant, savannah buffalo and common river hippopotamus) from the three major parks of Uganda using both microsatellite loci (for elephant and warthog populations) and mitochondrial control sequence variation in the warthogs, elephants, buffaloes and hippopotamuses. Queen Elizabeth National Park showed extreme reduction in nucleotide diversity for two species, the common warthog (π= 0.0%) and African elephant (π= 0.4%); no such decrease was found for the two other species, the buffalo (π= 3.7–5.4%) and hippopotamus (π= 1.7–1.9%), in the three parks. Nuclear microsatellite markers on the other hand showed high gene diversity in all populations in the common warthog (mean He 0.66–0.78) and the African savannah elephant (mean He 0.68–0.72). We interpret these results in terms of varying poaching pressure in the different parks, susceptibility of different species to poaching and differences in effective population sizes at the mitochondrial and nuclear loci.
Impact of fire management on the ecology of collared lizard (Crotaphytus collaris) populations living on the Ozark Plateau
Authors: Brisson Jennifer A. , Strasburg Jared L. , Templeton Alan R. 
Published: September 2003

AbstractEastern collared lizards (Crotaphytus collaris collaris) on the Ozark Plateau of southern Missouri are restricted to islands of rocky glade habitat located throughout the oak‐hickory forests of the region. Human mediated suppression of fire negatively impacts collared lizard populations by permitting the overgrowth and consequent disappearance of this glade habitat and also leads to a dense forest understorey that impedes movement of lizards between glades. We present data examining the effects of a fire management regime on collared lizard populations we monitored via mark/recapture from 1998 to 2001. We demonstrate increased glade‐to‐glade dispersal, colonization of previously unoccupied glades, and a significant increase in population size in the burned area. In addition, we show that populations within burned areas exhibit body sizes similar to those reported for populations living on healthy habitat as compared to those living on habitat that has deteriorated because of fire suppression. We conclude that managed forest fires positively impact collared lizard populations in the Ozarks, promoting factors that increase the long‐term sustainability of the species.
The role of local adaptation in metapopulation restorations
Authors: Robert Alexandre , Couvet Denis , Sarrazin François 
Published: September 2003

AbstractWe propose an original approach to model the effect of the initial spatial distribution of a reintroduced metapopulation (one‐patch release versus multi‐patch release) on local adaptation. Genetic and demographic processes are considered to investigate how the different patterns of adaptation resulting from initial conditions affect metapopulation viability. In agreement with classical interpretations in the fields of population biology and evolutionary genetics, we observe an influence of the degree of environmental correlation among patches on demographic processes and an influence of inter‐patch connection on genetic processes. However, our results uncover some further effects of the environment, owing to positive feedback interactions among demographic and genetic processes. When considering the one‐patch release, demographic stochasticity engenders a delay in the colonization of initially empty patches. This delay enhances the genetic asymmetry among patches (in terms of local adaptation), which in turn increases demographic asymmetry. In contrast, the multi‐patch release produces similar levels of adaptation among patches. Metapopulation dynamics is strongly influenced by these differences, with contrasting effects under different environments. The pattern of adaptation produced by the one‐patch release strategy is optimal under a regime of recurrent slight perturbations or environmental stochasticity, while the multi‐release strategy is optimal in the presence of rare and severe perturbations.
Genetic identification of wild Asian water buffalo in Nepal
Authors: Flamand J. R. B. , Vankan D. , Gairhe K. P. , Duong H. , Barker J. S. F. 
Published: September 2003

AbstractThe wild water buffalo is highly endangered, with the few remaining populations already affected or likely to be increasingly affected by hybridization with domestic buffalo. The work described here was done to evaluate a genetic method to discriminate wild from mixed ancestry (hybrid) and domestic animals, and to identify with high probability those most likely to be purebred wild. Samples from 45 animals (phenotypically classified into three groups ‐ ten wild, 28 domestic and seven hybrid) were genotyped for ten microsatellite loci. Although genetic distances among the three groups were small, an assignment test identified two of the ‘wild’ and seven of the ‘domestic’ as hybrids. However, sample sizes also are small, indicating the need for a conservative approach in the first instance in using these results. As more animals are genotyped, assignments will become more accurate, and a translocation programme to establish a second Nepalese wild population in a protected area could be undertaken.
The influence of scale on salmon habitat restoration priorities
Authors: Feist Blake E. , Steel E. Ashley , Pess George R. , Bilby Robert E. 
Published: September 2003

AbstractHabitat loss and alteration is the leading cause of species' declines world‐wide, therefore habitat restoration and protection is a prominent conservation strategy. Despite obvious connections between habitat and threatened or endangered species, conservationists have been hard pressed explicitly to link abundance or population health with habitat attributes. Given that habitat relationships with species are often characterized at a spatial scale that does not account for the functional relationships between habitat and populations, it is not surprising that the habitat‐population conundrum persists. In order to explore the influence of spatial scale on the apparent relationship between habitat and populations, we examined the relationship between GIS‐based habitat data and spring/summer chinook salmon (Oncorhynchus tshawytscha) redd (spawning nests built by females) densities in the Salmon River basin, Idaho, at two very different spatial scales: stream reach and watershed. Redd density was strongly correlated with climate, geology, wetlands and terrain. However, our stream‐reach scale models provided poor predictive power compared with the watershed scale models. Based on these results, we conclude that our perception of which habitat attributes were important was clearly a function of our scale of observation, and that restoration efforts should focus on conditions at the watershed or landscape scale when attempting to do local or reach scale restoration projects.
Movement and survival parameters of translocated and resident swift foxes Vulpes velox
Authors: Moehrenschlager Axel , Macdonald David W. 
Published: September 2003

AbstractConservation programmes increasingly involve the translocation of animals to reinforce failing populations or establish new ones. To help guide translocation programmes of swift foxes (Vulpes velox) or other imperilled species, we aimed to discern factors affecting translocation success among reintroduced swift foxes in Canada. Post‐release movements characterized three stages. In the initial acclimation phase, foxes moved erratically and quickly distanced themselves from release sites. During the establishment phase, distances from the release site did not change significantly but daily movements were more wide‐ranging than those of concurrently tracked, resident swift foxes. In the final settlement phase, movements of translocated foxes reflected those of resident individuals. Radio‐telemetry showed that survival and reproductive success were highest for swift foxes with small dispersal distances, suggesting that measures should be taken to acclimatize animals to release sites. Since females had lower survival rates than males, translocations should also use a greater proportion of females to establish balanced sex ratios in the population. Translocated juveniles dispersed less far but survived and reproduced as well as translocated adults, suggesting that juveniles can be used to establish translocated foxes in small, protected areas, while minimizing demographic effects on source populations. The fact that survival rates and litter sizes of translocated foxes were similar to those of resident animals indicates that translocation can be an effective reintroduction tool for this endangered species, and possibly other foxes.
Misleading hallucinations in unrecognized narcolepsy
Authors: Szűcs A. , Janszky J. , Holló A. , Migléczi G. , Halász P. 
Published: September 2003

Objective: To describe psychosis‐like hallucinatory states in unrecognized narcolepsy.Method: Two patients with hypnagogic/hypnapompic hallucinations are presented.Results: Both patients had realistic and complex – multi‐modal and scenic‐daytime sexual hallucinations leading, in the first case, to a legal procedure because of false accusation, and in the second, to serious workplace conflicts. Both patients were convinced of the reality of their hallucinatory experiences but later both were able to recognize their hallucinatory character. Clinical data, a multiple sleep latency test, polysomnography, and HLA typing revealed that both patients suffered from narcolepsy.Conclusion: We suggest that in unrecognized narcolepsy with daytime hypnagogic/hypnapompic hallucinations the diagnostic procedure may mistakenly incline towards delusional psychoses. Daytime realistic hypnagogic/hypnapompic hallucinations may also have forensic consequences and mislead legal evaluation. Useful clinical features in differentiating narcolepsy from psychoses are: the presence of other narcoleptic symptoms, features of hallucinations, and response to adequate medication.
Postmaturity in a genetic subtype of schizophrenia
Authors: Chow E. W. C. , Husted J. , Weksberg R. , Bassett A. S. 
Published: September 2003

Objective: To determine whether postmaturity (gestation > 41 weeks), small for gestational age (SGA), and other pregnancy and birth complications that may elevate risk for neurodevelopmental disorders, are associated with elevated risk for schizophrenia in 22q11 Deletion Syndrome (22qDS), a genetic subtype of schizophrenia.Method: Antepartum and intrapartum features were examined in 20 adults with 22qDS‐schizophrenia and three comparison groups: newborn encephalopathy (n = 164) and healthy newborn controls (n = 400) from Badawi et al.'s (Br Med J 1998, 317: 1549) study, and 16 non‐psychotic 22qDS adults (22qDS‐NP).Results: Postmaturity (OR 13.0, 95% CI 3.95, 42.77; P < 0.001) and SGA (OR 3.59, 95% CI 1.23, 10.5; P = 0.03) were more prevalent in 22qDS‐SZ than controls. Postmaturity was non‐significantly more prevalent in 22qDS‐SZ than in newborn encephalopathy (P = 0.06) or 22qDS‐NP (P = 0.2). SGA showed similar rates in the two 22qDS groups and newborn encephalopathy, but was more prevalent in 22qDS‐NP than controls (P = 0.05).Conclusion: The results suggest that postmaturity may be associated with expression of schizophrenia in a 22qDS subtype of schizophrenia. SGA may be a non‐specific marker of neurodevelopmental disturbance.
Depression and subjective quality of life in chronic phase schizophrenic patients
Authors: Reine G. , Lançon C. , Di Tucci S. , Sapin C. , Auquier P. 
Published: September 2003

Objective: To evaluate the influence of depression on subjective quality of life in schizophrenic patients.Method: Sixty‐seven schizophrenic patients in a stabilized phase were included. Schizophrenic symptoms were evaluated using the Positive and Negative Symptoms Scale (PANSS). The subjective quality of life was evaluated using the short version of the Lehman quality of life scale (QoLI). Depression was evaluated using the Calgary Depression Scale for Schizophrenia (CDSS) and extrapyramidal effects with the Extrapyramidal Symptoms Rating Scale (ESRS).Results: The PANSS total score, PANSS general psychopathology subscore, PANSS depression factor, the total CDSS and some ESRS scores were negatively correlated with the overall life satisfaction score. The CDSS score was negatively correlated with all except one QoLI score. QoLI scores were significantly lower in depressed patients, and this result remained consistent for four QoLi dimensions when adjusted on ESRS and PANSS scores. When analysing the association between high depression scores and high parkinsonism scores with reduced quality of life, multivariate analysis showed that depression was the main explanatory factor: the CDSS total score explained 22% of the variance of the overall subjective quality of life score. The patient questionnaire at the ESRS explained 10.5% of the variance of the ‘mental and physical health’ QoLI score.Conclusion: In schizophrenic patients, depressive symptoms should be focused because of their strong association to overall subjective quality of life.
Brain morphological abnormality in schizophrenia is independent of country of origin
Authors: Chua S. E. , Lam I. W. S. , Tai K.‐S. , Cheung C. , Tang W.‐N. , Chen E. Y. H. , Lee P. W. H. , Chan F.‐L. , Lieh‐Mak F. , McKenna P. J. 
Published: September 2003

Objective: The disorder schizophrenia has a worldwide prevalence of 1% and is generally associated with lateral cerebral ventricular enlargement. Whether there is a relationship between these two findings is unclear but has aetiological relevance.Method: Consecutively admitted Chinese patients (n = 19) with first episode of schizophrenia and healthy community volunteers (n = 29) underwent magnetic resonance imaging brain scan. The groups were balanced for age, sex, best social class and handedness. These patients were similar on clinical and socio‐demographic indices to those who declined participation (n = 15). Semi‐automated volumetric analysis of whole brain volume, cortical grey matter, cerebrospinal fluid, sulci and lateral ventricles was performed.Results: Chinese patients in their first episode of schizophrenia have significant enlargement of lateral ventricles.Conclusion: Brain morphological abnormality in schizophrenia is present regardless of the country of origin. The importance of genes in driving normal brain development and stable prevalence suggests that aetiology may favour genes over environment.
Attention profile in schizophrenia compared with depression: differential effects of processing speed, selective attention and vigilance
Authors: Egeland J. , Rund B. R. , Sundet K. , Landrø N. I. , Asbjørnsen A. , Lund A. , Roness A. , Stordal K. I. , Hugdahl K. 
Published: September 2003

Objective: The aim of the study is to investigate whether subjects with schizophrenia and major depression display attention deficits for different reasons.Method: Subjects with schizophrenia (n = 53), recurrent major depression (n = 50) and normal controls (n = 50) were administered with 11 measures of processing speed, selective attention and vigilance. Indices of basal speed, speeded attention, non‐speeded attention and vigilance were computed.Results: Both clinical groups were impaired on all chronometric tests. The schizophrenic subjects were also more impaired on speeded attention compared with basal processing speed. Only the schizophrenics were impaired on the non‐speeded measures of selective attention. Compared with the schizophrenics, the depressives showed a decrement in vigilance.Conclusion: Reduced performance on attention tests in major depression is because of a non‐specific speed reduction and loss of vigilance consistent with lack of effort. In addition to generally impaired processing speed, the schizophrenic subjects exposed a deficit in selective attention, indicating executive dysfunction.
The stigma of mental illness: effects of labelling on public attitudes towards people with mental disorder
Authors: Angermeyer M. C. , Matschinger H. 
Published: September 2003

Objective: Aim of the study is to examine the impact of labelling on public attitudes towards people with schizophrenia and major depression.Method: In Spring 2001, a representative survey was carried out in Germany involving adults of German nationality (n = 5025).Results: Labelling as mental illness has an impact on public attitudes towards people with schizophrenia, with negative effects clearly outweighing positive effects. Endorsing the stereotype of dangerousness has a strong negative effect on the way people react emotionally to someone with schizophrenia and increases the preference for social distance. By contrast, perceiving someone with schizophrenia as being in need for help evokes mixed feelings and affects people's desire for social distance both positively and negatively. Labelling has practically no effect on public attitudes towards people with major depression.Conclusion: Our findings illustrate the need for differentiation, differentiation between the different components of stigma as well as differentiation between the various mental disorders.