bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent drastic changes in the gammarid fauna (Crustacea, Amphipoda) of the Vistula River deltaic system in Poland caused by alien invaders
Authors: Jazdzewski Krzysztof , Konopacka Alicja , Grabowski Michal 
Published: February 2004

ABSTRACTDuring the last decade of 20th century, the nonindigenous gammarid species Gammarus tigrinus, Dikerogammarus haemobaphes, Pontogammarus robustoides and Obesogammarus crassus invaded the lower Vistula River and its deltaic, partly brackish regions. G. tigrinus, an oligohaline North‐American species, was introduced to western Europe in the 1950s; the remaining three species are oligohaline/freshwater Ponto‐Caspian species. All these species are now invading central and western Europe using the network of man‐made canals connecting different European river systems. In the Vistula River, the native European freshwater gammarid species Gammarus pulex and G. varsoviensis were replaced in the 1920s by the Ponto‐Caspian Chaetogammarus ischnus (syn. Echinogammarus ischnus), which in turn has been outnumbered by the more recent invasions of D. haemobaphes and P. robustoides. In brackish waters, the native Atlantic‐boreal species Gammarus zaddachi and Gammarus duebeni are replaced or at least outnumbered by G. tigrinus, P. robustoides and O. crassus. Possible invasion routes are discussed.
A parametric diversity measure combining the relative abundances and taxonomic distinctiveness of species
Authors: Ricotta Carlo 
Published: February 2004

ABSTRACTMost ecological diversity indices summarize the information about the relative abundances of species without reflecting taxonomic differences between species. Nevertheless, in environmental conservation practice, data on species abundances are mostly irrelevant and generally unknown. In such cases, to summarize the conservation value of a given site, so‐called ‘taxonomic diversity’ measures can be used. Such measures are based on taxonomic relations among species and ignore species relative abundances. In this paper, bridging the gap between traditional biodiversity measures and taxonomic diversity measures, I introduce a parametric diversity index that combines species relative abundances with their taxonomic distinctiveness. Due to the parametric nature of the proposed index, the contribution of rare and abundant species to each diversity measure is explicit.
Pleural complications of pulmonary hydatid disease
Authors: Ozvaran Mustafa Kursat , Ersoy Yesim , Uskul Bahadir , Unver Ethem , Yalcin Engin , Baran Reha , Morice Rodolfo C. 
Published: February 2004

Objective:  The aim of this study was to determine the incidence and diagnostic features of pleural manifestations of pulmonary hydatid disease.Methodology:  Patients with pleural pathology in association with surgery for pulmonary hydatid disease over an 8‐year period were evaluated.Results:  Twenty‐nine (6%) of 474 patients with histologically confirmed pulmonary hydatid disease had pleural abnormalities. The diagnosis was determined preoperatively in 22 patients and was based on radiographic, clinical, and/or serology findings. Bronchoscopic specimens were diagnostic in two of seven patients who had bronchoscopy. Five patients were not diagnosed until surgery. Radiographic abnormalities consisted of pleural thickening and/or free fluid without intrapleural rupture of the cysts in 21 patients. Eight patients had a hydropneumothorax. Sixteen patients had an exudative, uncomplicated effusion. The remaining patients had empyemas. All patients had resection of the pulmonary cysts, and 20 also underwent a pleurectomy. The mean length of hospital stay was 23 ± 14 days. There was no hospital mortality.Conclusion:  Pleural lesions associated with pulmonary hydatid disease are rare and have a variable radiographic appearance. In regions in which echinococcal disease is endemic, a high level of clinical suspicion is necessary for diagnosis and appropriate management of this condition.
Incidence of community‐acquired pneumonia in children caused by Mycoplasma pneumoniae: Serological results of a prospective, population‐based study in primary health care
Authors: Korppi Matti , Heiskanen‐Kosma Tarja , Kleemola Marjaana 
Published: February 2004

Objective:  The objective of the present study was to assess the incidence of community‐acquired pneumonia (CAP) in children caused by Mycoplasma pneumoniae.Methodology:  During 12 months in 1981–1982, all CAP cases in a defined child population were registered. M. pneumoniae aetiology, initially measured by complement fixation (CF) test, was in 1999 supplemented by measurement of IgG and IgM antibodies using enzyme immunoassays (EIA).Results:  M. pneumoniae was detected in 61 (30%) of 201 paediatric CAP cases, being the most common aetiological agent in those 5 years of age or over. At that age, M. pneumoniae was responsible for over 50% of cases, and over 90% of mycoplasmal cases were treated as outpatients. The EIA detected 17 new cases over and above the 44 detected by CF, while CF alone revealed 10 cases. The incidence of M. pneumoniae CAP increased with age, being over 10/1000 children at the age of 10 years or more. Co‐infections with Streptococcus pneumoniae and Chlamydia pneumoniae were present in over 30% and 15%, respectively, of mycoplasmal CAP cases.Conclusion:  M. pneumoniae is a common cause of paediatric CAP in primary health care, and co‐infections with S. pneumoniae are common. Both S. pneumoniae and M. pneumoniae should be taken into account when starting antibiotics for children with CAP.
The influence of dexamethasone on the proliferation and apoptosis of pulmonary inflammatory cells in bleomycin‐induced pulmonary fibrosis in rats
Authors: Li Hui‐ping , Li Xia , He Guo‐jun , Yi Xiang‐hua , Kaplan Allen P. 
Published: February 2004

Objective:  The aim of this study was to investigate the inhibitory effect of dexamethasone on the state of proliferation/apoptosis of the pulmonary inflammatory cells in a rat pulmonary fibrosis model induced by bleomycin.Methodology:  Seventy‐five pathogen‐free Sprague‐Dawley (SD) rats were randomly divided into three groups: control, bleomycin (BLM) and dexamethasone (DXM) groups with 25 rats in each group. Each group was then divided into five subgroups based on time of study (1‐, 3‐, 7‐, 14‐ and 28‐days). BAL fluid was obtained, the cells were counted and a differential was performed. A lower DNA content in apoptotic cells was detected and quantitated by flow cytometry. Haematoxylin and eosin staining was performed to observe the extent of alveolitis and fibrosis of lung tissue; the morphological changes in apoptotic cells were discerned by transmission electron‐microscopy and a semi‐quantitative assessment of apoptotic cells in lung tissue was performed using in situ TUNEL (terminal deoxynucleotidyl transferase‐mediated dUTP nick endlabelling).Results:  The total number of inflammatory cells and the percentage of neutrophils in BAL fluid in almost every subgroup of the DXM group were significantly lower than those in corresponding subgroups of the BLM group (P < 0.01). The percentages of apoptotic cells in BAL fluid in the 14‐day and 28‐day subgroups of the DXM group were higher than those in corresponding subgroups of the BLM group (P < 0.05). The peak of alveolitis in the DXM group shifted backward and the extent of fibrosis was less than that in the BLM group. The apoptosis index (AI) of inflammatory cells in each of the DXM subgroups was higher than that in corresponding BLM subgroups except for day 14.Conclusion:  Dexamethasone can induce apoptosis of pulmonary inflammatory cells and reduce the extent of alveolitis and fibrosis in bleomycin‐induced pulmonary fibrosis of rats.
Intracellular glutathione in stretch‐induced cytokine release from alveolar type‐2 like cells
Authors: Jafari Behrouz , Ouyang Bin , Li Li‐Fu , Hales Charles A. , Quinn Deborah A. 
Published: February 2004

Objective:  Ventilator‐induced lung injury (VILI) is characterized by release of inflammatory cytokines, but the mechanisms are not well understood. We hypothesized that stretch‐induced cytokine production is dependent on oxidant release and is regulated by intracellular glutathione (GSH) inhibition of nuclear factor κB (NF‐κB) and activator protein‐1 (AP‐1) binding.Methodology:  Type 2‐like alveolar epithelial cells (A549) were exposed to cyclic stretch at 15% strain for 4 h at 20 cycles/min with or without N‐acetylcysteine (NAC) or glutathione monoethylester (GSH‐e) to increase intracellular GSH, or buthionine sulfoximine (BSO), to deplete intracellular GSH.Results:  Cyclic stretch initially caused a decline in intracellular GSH and a rise in the levels of isoprostane, a marker of oxidant injury. This was followed by a significant increase in intracellular GSH and a decrease in isoprostane. Stretch‐induced IL‐8 and IL‐6 production were significantly inhibited when intracellular GSH was further increased by NAC or GSH‐e (P < 0.0001). Stretch‐induced IL‐8 and IL‐6 production were augmented when intracellular GSH was depleted by BSO (P < 0.0001). NAC blocked stretch‐induced NF‐κB and AP‐1 binding and inhibited IL‐8 mRNA expression.Conclusions:  We conclude that oxidant release may play a role in lung cell stretch‐induced cytokine release, and antioxidants, which increase intracellular GSH, may protect lung cells against stretch‐induced injury.
Trace elements as a component of oxidative stress in COPD
Authors: Karadag Fisun , Cildag Orhan , Altinisik Mustafa , Kozaci Leyla D. , Kiter Goksel , Altun Cagatay 
Published: February 2004

Objective:  The purpose of this study was to assess the serum concentrations of those trace elements that act as a component of oxidative stress in COPD patients. Clinically stable COPD outpatients (n = 26) and healthy controls (n = 24) were studied.Methodology:  Serum concentrations of copper (Cu) and zinc (Zn) were determined using a Varian Spectra AA220 flame atomic absorption spectrophotometer. Serum concentration of iron (Fe) was measured by the ferene assay, using a commercially available kit (IL TestTM Iron) with the ILAbTM 900 autoanalyser. The lipid peroxidation product malondialdehyde (MDA) in serum samples was measured spectrophotometrically in terms of TBARS (thiobarbituric acid reactive substances).Results:  The serum MDA concentration in COPD patients was found to be similar to the control group (0.68 ± 0.15 nmol/mL vs 0.62 ± 0.13 nmol/mL, respectively; P= 0.163). The serum concentrations of the trace elements in both study groups were in the normal reference range. There was no difference in Fe concentration between COPD patients and the control group (0.81 ± 0.38 µg/mL vs 0.92 ± 0.41 µg/mL; P= 0.360). Copper concentrations were higher (1.06 ± 0.26 µg/mL vs 0.92 ± 0.19 µg/mL; P <0.040); while zinc was lower in the COPD group compared to the controls (0.83 ± 0.25 µg/mL vs 1.03 ± 0.23 µg/mL; P= 0.006). Serum Zn concentrations were lower in the severe COPD patients compared to mild‐moderate COPD patients (P = 0.038).Conclusion:  The results of this study indicate that there are alterations in serum concentrations of trace elements in COPD patients, suggesting that they may play a role in the pathophysiology of this disease by virtue of their role in oxidative stress. We recommend further studies on the role of trace elements in the pathophysiology of COPD, their association with markers of oxidant/antioxidant status and on the clinical significance of their deficiency.
Site fidelity in temporally correlated environments enhances population persistence
Authors: Schmidt Kenneth A. 
Published: February 2004

AbstractSite fidelity, the phenomenon of remaining faithful to sites, often where an individual has bred successfully in the past, has important consequences for population dynamics. Previous results have shown that site fidelity results in a positive correlation between population density and fitness. Here, I build on this theme by incorporating site fidelity using the win‐stay : lose‐switch rule often seen among birds, i.e. individuals return to sites were they bred successfully in the past and vacate those where they have not. Results demonstrate that the combination of site fidelity and temporal autocorrelation in site quality can enhance the persistence of population networks, whereas either factor acting alone has little or no influence. Moreover, there is an abrupt threshold at moderate levels of temporal autocorrelation,ρtime > 0.35–0.4, beyond which persistence time and the probability of surviving >500 years is greatly accelerated. These results suggest that temporal autocorrelation combined with appropriate behavioural responses may enhance population persistence.
Consumer effects decline with prey diversity
Authors: Hillebrand Helmut , Cardinale Bradley J. 
Published: February 2004

AbstractWhile consumer species diversity is known to influence the capture of limited resources, little is known about how prey diversity impacts the transfer of energy and matter among trophic levels. Here, we perform a meta‐analysis of experiments that have examined the impact of grazers on the biomass of periphytic algae to test the hypothesis that the magnitude of consumer (grazer) effects on prey (algae) depends on the species diversity of the prey assemblage. The analysis reveals that consumer effects tend to decrease as the diversity of a prey assemblage increases. This trend is robust for several different, yet complementary indices of grazer effect size and algal diversity. The trend also remains significant after statistically controlling for a variety of factors that can covary with prey diversity among studies. We discuss several possible mechanisms for the documented pattern, such as diversity enhancing the probability of inedibility and of positive interactions.
A novel genealogical approach to neutral biodiversity theory
Authors: Etienne Rampal S. , Olff Han 
Published: February 2004

AbstractCurrent neutral theory in community ecology views local biodiversity as a result of the interplay between speciation, extinction and immigration. Simulations and a mean‐field approximation have been used to study this neutral theory. As simulations have limitations of convergence and the mean‐field approximation ignores dependencies between species’ abundances when applied to species‐abundance data, there is still no final conclusion whether the neutral theory or the traditional lognormal model describes community structure best. We present a novel analytical framework, based on the genealogy of individuals in the local community, to overcome the problems of previous approaches, and show, using Bayesian statistics, that the lognormal model provides a slightly better fit to the species‐abundance distribution of a much‐discussed tropical tree community. A key feature of our approach is that it shows the tight link between genetic and species diversity, which creates important perspectives to future integration of evolutionary and community ecological theory.
Quantifying the effects of fisheries on threatened species: the impact of pelagic longlines on loggerhead and leatherback sea turtles
Authors: Lewison Rebecca L. , Freeman Sloan A. , Crowder Larry B. 
Published: February 2004

AbstractThe depletion of fish stocks from global fisheries has been a long‐standing concern. More recently, incidental catch of non‐target (termed bycatch) vertebrates also has been proposed as a serious conservation issue. Here we present a bycatch assessment for loggerhead and leatherback sea turtles that are incidentally caught by global pelagic longlines. We integrate catch data from over 40 nations and bycatch data from 13 international observer programmes. Despite infrequent rates of encounter, our analyses show that more than 200 000 loggerheads and 50 000 leatherbacks were likely taken as pelagic longline bycatch in 2000. Our analyses suggest that thousands of these turtles die each year from longline gear in the Pacific Ocean alone. Given 80–95% declines for Pacific loggerhead and leatherback populations over the last 20 years, this bycatch level is not sustainable. Adopting a large‐scale, synthetic approach is critical to accurately characterize the influence of global fisheries bycatch on globally distributed and imperilled pelagic vertebrates.
Use of forward versus backward reasoning during audit analytical procedures: evidence from a computerised‐process‐tracing field study
Authors: O'Donnell Ed 
Published: February 2004

AbstractAudit judgement research has widely assumed that auditors rely primarily on backward reasoning during analytical procedures but the relative use of forward reasoning has not been directly examined. The present study explains how auditors use backward and forward reasoning during analytical procedures, discusses evidence from other research suggesting that forward reasoning could be more prevalent, and examines the relative use of forward reasoning during analytical procedures with data from a computerised process‐tracing field study. Results suggest that auditors rely extensively on forward reasoning when using analytical procedures. Findings motivate future research that examines when forward and backward reasoning are most effective.
Impact of intelligent decision aids on expert and novice decision‐makers’ judgments
Authors: Arnold Vicky , Collier Philip A. , Leech Stewart A. , Sutton Steve G. 
Published: February 2004

AbstractBusinesses have invested tremendous resources into intelligent decision aid development. A good match between user and aid may improve the expert decision‐maker's decision quality. However, novices may be prone to poorer decision‐making if intelligent decision aids are more expert than the user. The present paper provides an empirical test of the impact of decision aids on subjects with differential expertise levels. The results support the contention that intelligent decision aids aggravate bias in novices’ decision‐making but mitigate bias in experts’ decision‐making processes. Intelligent decision aids may be best viewed as complements to expert decision‐makers during complex problem analysis and resolution.
Stock preferences and derivative activities of Australian fund managers
Authors: Pinnuck Matt 
Published: February 2004

AbstractThe present paper examines both the characteristics of stocks that fund managers prefer to hold and their use of derivatives. We find strong evidence that fund managers prefer large, liquid and low volatility stocks. Weak evidence exists that fund managers prefer to hold stocks that are past winners. In relation to derivatives, just over half of the sampled Australian fund managers hold derivatives in the form of exchange traded options. Of those that do trade in derivatives, it is found the level of exposure to stock price movements achieved by options is not significant relative to the total investment portfolio.
Annotation: The similarities and differences between autistic disorder and Asperger's disorder: a review of the empirical evidence
Authors: Macintosh Kathleen E. , Dissanayake Cheryl 
Published: February 2004

Background: The ongoing controversy over the distinction between autistic disorder and Asperger's disorder is important to resolve because of the implications regarding an understanding of the aetiology and prognosis, and the diagnostic and clinical practices relating to these conditions. This paper provides a critical evaluation of current published research evidence.Method: Databases, such as PsychINFO and Medline, as well as book chapters, reference lists from relevant articles, and recent editions of key journals were searched for all relevant studies (until 2002) which incorporated participants diagnosed with high‐functioning autism and Asperger's disorder using either cluster analysis or comparative approaches to examine similarities and differences between these groups. Keywords used in the searches included autistic disorder, Asperger's disorder, autism, high‐functioning autism, and pervasive developmental disorder.Results: On the basis of the available evidence, there seem to be few qualitative differences between autistic disorder and Asperger's disorder.Conclusion: There is currently insufficient evidence to establish the validity of Asperger's disorder as a syndrome distinct from high‐functioning autism. The findings are consistent with the view that these disorders belong on an autism spectrum.
Attention orienting by another's gaze direction in children with autism
Authors: Kylliäinen Anneli , Hietanen Jari K. 
Published: February 2004

Background:  The aim of this study was to investigate attention orienting triggered by another's gaze direction in autism.Method:  Twelve high‐functioning children with autism and gender‐ and age‐matched normal control children were studied using two tasks. In the first task, children were asked to detect laterally presented target stimuli preceded by centrally presented facial cue stimuli in which gaze was either straight ahead or averted. The direction of the cue was either congruent, neutral, or incongruent with respect to the laterality of the target stimulus. In the second task, children were asked to discriminate the direction of eye gaze.Results:  The results showed that another person's static gaze direction triggered an automatic shift of visual attention, both in children with autism and in normally developing children. The children in both groups were also able to overtly discriminate the direction of the gaze.Conclusion:  These results seem to suggest that, in children with autism, the visual system processes information about another person's gaze direction and sends this information to those areas that subserve reflexive attention orienting. However, future studies are needed to investigate whether the processing of eyes and gaze direction relies on similar neural mechanisms in children with autism and in normally developing children.
Gestalt processing in autism: failure to process perceptual relationships and the implications for contextual understanding
Authors: Brosnan Mark J. , Scott Fiona J. , Fox Simone , Pye Jackie 
Published: February 2004

Background:  Deficits in autism have been characterised as a bias towards local over global processing. This paper examines whether there is a deficit in gestalt grouping in autism.Method:  Twenty‐five low‐functioning children with autism and 25 controls who were matched for chronological age and verbal mental age took part in the study.Results:  The autism group utilised gestalt grouping principles (proximity, similarity, closure) significantly less than the controls. Calculating an overall index of gestalt grouping, the autism group performed at chance level. There was also a deficit in identifying certain impossible figures. This pattern was not reflected in a drawing task, in which the autism sample conformed more to gestalt grouping principles than controls (non‐significantly).Conclusions:  The results are discussed in terms of a failure in autism to process inter‐element relationships that would allow for the appreciation of larger perceptually coherent units that comprise of multiple elements and, consequently, context. The processes are argued to be preattentive.