bluuebunny/crossref_metadata_2025_split huggingface dataset:
Variability in the development, persistence and breakdown of thermal, oxygen and salt stratification on regulated rivers of southeastern Australia
Authors: Turner Lisa , Erskine Wayne D. 
Published: March 2005

AbstractDetailed depth profiles of temperature, dissolved oxygen, salinity and oxidation‐reduction potential (ORP) at many sites over two to four years were made on three highly regulated rivers in southeastern Australia which have experienced large‐scale streamflow reductions for urban water supply (Nepean River) or urban, stock and domestic supplies (Glenelg River) or hydropower generation (Snowy River). Well‐developed oxygen stratification was detected on all rivers in summer and was associated with thermal stratification. Hypoxia or anoxia was often measured below the oxycline and reducing conditions (ORP up to −200 mv) were usually associated with such anoxia. Saline groundwater inflows were detected on both the Nepean and Glenelg rivers and produced salt stratification in addition to thermal and oxygen stratification. Density differences of up to 3.7 kg/m3 were determined across the oxycline with no salt stratification, but increased to 14.9 kg/m3 when salt stratification occurred in the upper estuary of the Snowy River. Sediment‐bound phosphorus was released under reducing conditions with order of magnitude increases in total phosphorus concentrations being measured below the oxycline. Similarly, increases of at least 50% and up to one order of magnitude in dissolved iron, aluminium, manganese and/or sulphur were also measured when anoxic and reducing conditions were recorded below the oxycline. Water depth exerted a significant control on thermocline development with depths of at least 5 m, but usually 6 m, being required for thermal stratification in pools. Deep natural scour pools stratify on all three rivers but dredging of weir pools on the Nepean River has increased the extent of stratification. Anoxic and/or hypoxic conditions below the oxycline greatly reduce the amount of aquatic habitat available for aerobic organisms, especially benthic fish. Winds of 50 km/h generated sufficient shear to completely overturn the stratified Cobbitty weir pool on the Nepean River and winds of 28–44 km/h completely mixed epilimnetic waters in Rocklands Reservoir, breaking down temporary thermoclines. Trial environmental streamflows of 21.7 to 40.7 m3/s generated epilimnetic flow velocities that caused sufficient turbulence to effect mixing by gradual entrainment on the Nepean River. However, these flows would need to persist for more than 5 days to break down stratification in the deepest pools. Stratification rapidly redeveloped, even on the recession of the releases. Copyright © 2005 John Wiley & Sons, Ltd.
The role of flooding in morphological changes in the regulated Lower Ord River in tropical northwestern Australia
Authors: Cluett Lisa 
Published: March 2005

AbstractThe discharge of the Lower Ord River has been regulated since 1972 when a second dam was built on this major river system. This previously ephemeral river, punctuated by peak wet season flows, is now characterized by permanent, regulated flows all year, and complex adjustments to the downstream channel morphology are evident. Geographic Information System techniques, combined with field surveys, reveal a series of interrelated adjustments in response to recent flooding. These include sedimentation, channel narrowing and vegetation encroachment, all of which have implications for sustainable management and are issues that have been managed by flushing flows in other rivers. The largest flood events since regulation occurred some 27 years after dam construction during consecutive wet seasons. These events have prompted an examination of the potential to ‚flush’︁ the post‐regulation Lower Ord channel to modify some of the channel changes that occurred in response to dam construction. A detailed geomorphic investigation of the Lower Ord river showed that that some of the features formed under low flows have been eradicated (partly or completely) by these large flood events, while others have withstood them. The modification of changes since dam construction varies according to a range of factors including reach position, extent of vegetation cover and local morphological variation. It is clear, however, that features not removed during floods may be considered quasi‐permanent, and therefore are likely to play an important role in the evolution of this regulated river. Copyright © 2005 John Wiley & Sons, Ltd.
Spatial variability and temporal change of water discharge and sediment flux in the Lower Jinsha tributary: impact of environmental changes
Authors: LU X. X. 
Published: March 2005

AbstractAnalysis of water discharge and sediment flux data as measured in the Longchuanjiang Basin in the Lower Jinsha tributary over the past few decades has been undertaken. The results of this study indicate that the lower reaches of the Longchuanjiang River produce relatively less runoff but higher sediment loads than the upper reaches. This can be attributed to the differences in climate, the dissected terrain and the sparse vegetation cover of the downstream river. Temporal series analysis suggests a significant increase in sediment flux, notably in the lower reaches of the river. The available data suggest the increasing sediment flux is a result of climate variations and a series of human activities such as land‐use changes, mainly through deforestation and agricultural expansion. Other activities, such as road construction, urban expansion, building‐material excavation and large‐scale terrace construction and afforestation, have also contributed to the significant increase in the sediment flux. However, the Longchuanjiang Basin as a whole has a low sediment yield (< 1000 t km−2 a−1), despite severe soil erosion in the catchment. This is a result of sediment deposition in the numerous reservoirs, constructed since the 1950s. Runoff in the dry season has also significantly declined due to increasing water consumption. These profound changes in the hydrological regime will have significant implications for effective soil erosion and water management. Further studies in the region are necessary to address the impact of these human activities on hydro‐geomorphological processes and, particularly, water discharge and sediment flux. Copyright © 2005 John Wiley & Sons, Ltd.
Linking scales of flow variability to lotic ecosystem structure and function
Authors: Biggs Barry J. F. , Nikora Vladimir I. , Snelder Ton H. 
Published: March 2005

AbstractObtaining a better knowledge of how flow variability affects lotic biota is of considerable importance to stream and river management. We contend that processes at different hierarchical levels of organization in lotic ecosystems are sensitive to variation in flow at related hierarchical temporal scales. Ecosystem disturbance caused by large‐scale events (i.e. infrequent, but high magnitude flow events with a recurrence interval of years to many days) tend to determine high‐level characteristics of ecosystem structure (e.g. determining species pools, periphyton versus macrophyte dominance) and function (e.g. balance between auto‐ and heterotrophy). The high‐level ecosystem characteristics then set the stage for processes that are influenced by flow variation that occurs at smaller temporal scale (i.e. minutes to milliseconds) such as colonization, biotic interactions and mass transfer enhancement of production. We contend that large‐scale temporal events predominantly affect lotic ecosystems through physical drag processes (‘drag‐disturbance’), whereas small‐scale flow variations affect ecosystems through mass‐transfer processes (including invertebrate and fish food‐uptake). Drag‐disturbance and mass‐transfer related processes mark the opposite ends of a continuum of flow variability controlled processes, with moderate temporal scale flow variability events affecting ecosystems through both drag‐disturbance and mass‐transfer processes in similar proportions. Flow variability, and associated effects on ecosystems, across these scales is discussed with reference to New Zealand rivers. We suggest that these concepts can be integrated across the full range of temporal scales based on a spectrum of velocity variations. This may provide a unifying conceptual model for how the structure and functioning of lotic ecosystems are linked to flow variability. Copyright © 2005 John Wiley & Sons, Ltd.
Chemical composition and mass closure for fine and coarse aerosols at a kerbside in Budapest, Hungary, in spring 2002
Authors: Maenhaut Willy , Raes Nico , Chi Xuguang , Cafmeyer Jan , Wang Wan , Salma Imre 
Published: March 2005

AbstractA comprehensive chemical aerosol characterization was carried out at a kerbside in downtown Budapest in spring 2002. Several filter samplers were deployed in parallel for day and night collections, and a total of 23 parallel collections were made. All samples were analysed for the particulate mass (PM) by weighing. Depending on the sampler type and/or collection substrate, further analyses were performed for up to 46 elements by a combination of particle‐induced x‐ray emission (PIXE) spectrometry and instrumental neutron activation analysis (INAA), for major anions and cations by ion chromatography and for organic carbon and elemental carbon by a thermal–optical transmission technique. Some of the elements measured could clearly be associated with traffic‐related sources, e.g. Cu and Sb were attributed to emissions from brake linings. Aerosol chemical mass closure calculations were made for the separate fine (<2 µm) and coarse (2–10 µm) size fractions and also for the PM10 aerosol. For reconstituting the gravimetric PM, eight aerosol types were considered, and three aerosol types were deduced from the PIXE/INAA elemental data set. Organic matter and elemental carbon were the dominant aerosol types in the fine fraction; they explained on average 43 and 21%, respectively, of the fine PM. The coarse PM consisted mainly of crustal matter (49%) and organic matter (30%). The large contribution from crustal matter (road dust) to the coarse fraction is consistent with other data from kerbside sites in Europe. Copyright © 2005 John Wiley & Sons, Ltd.
Differential PIXE measurements for the stratigraphic analysis of the painting Madonna dei fusi by Leonardo da Vinci
Authors: Grassi N. , Migliori A. , Mandò P. A. , Calvo del Castillo H. 
Published: March 2005

AbstractTraditional PIXE does not provide information about the layered structure that is characteristic of wood and canvas paintings. In such cases, a solution to discriminate the depth sequence of elements within the analysed sample is to use differential PIXE, i.e. by measuring on the same spot with different beam energies. At the Florence accelerator, laboratory differential PIXE measurements were performed on the wood painting Madonna dei fusi (ex‐Redford version, 1501) by Leonardo da Vinci, in the framework of an extensive project aimed at discovering the ‘secrets’ of the painting and drawing techniques of the artist. The analysis allowed us to characterize the pigments and the substrate composition. Copyright © 2005 John Wiley & Sons, Ltd.
PIXE analysis of atmospheric aerosols in Mexico City
Authors: Miranda J. , Barrera V. A. , Espinosa A. A. , Galindo O. S. , Meinguer J. 
Published: March 2005

AbstractSamples of atmospheric aerosols were collected at three sites in the metropolitan area of Mexico City and analyzed with particle‐induced x‐ray emission (PIXE). Stacked filter units of the Davis design were employed to obtain samples of PM15 (particles with dimensions below 15 µm mean aerodynamic diameter) on polycarbonate filters, divided in two fractions. The study was conducted during the first half of 2002, exposing the filters every 2 days for 24 h, starting at 08:00 h. Analysis of variance of the measured elemental concentrations showed differences in the mean concentrations for several elements at the sampling sites. Cluster and absolute principal component analyses were applied to identify contributing sources, together with their relative contributions to the mass measured with PIXE. It was found that fugitive dusts are usually the main sources in both fractions from all sites. Copyright © 2005 John Wiley & Sons, Ltd.
Characterization of airborne particulate matter in an industrial district near Florence by PIXE and PESA
Authors: Chiari M. , Lucarelli F. , Mazzei F. , Nava S. , Paperetti L. , Prati P. , Valli G. , Vecchi R. 
Published: March 2005

AbstractThe composition of airborne particulate matter in Montelupo Fiorentino (a small town about 20 km west of Florence characterized by the presence of a large number of ceramic and glass factories) was studied by means of continuous and sequential sampling, ion beam analysis (IBA) techniques and statistical methods. The aerosol PM10 fraction was collected on a daily basis for about 9 months (September 2002–June 2003). To investigate the elemental size distribution, for a shorter period (about 3 weeks) we collected PM10, PM2.5 and PM1 simultaneously. A continuous streaker sampler was also used, which allows the study of the aerosol composition with 2 h time resolution. Mass concentrations were obtained using an analytical balance. The elemental analysis was performed at the INFN accelerator laboratory at the Physics Department of Florence University by particle‐induced x‐ray emission and particle elastic scattering analysis (the latter implemented for this campaign). The use of the two techniques allowed a complete reconstruction of the gravimetric mass. An absolute principal component analysis showed industrial sources to be, on average, the main contributors to PM10 mass; however, the weight of the ‘soil’ source (connected to local soil re‐suspension and to long‐range Saharan transport episodes) becomes dominant during some of the days when the 50 µg m−3 limit is exceeded. Copyright © 2005 John Wiley & Sons, Ltd.
Developing an operational reference framework for fisheries management on the basis of a two-dimensional index of ecosystem impact
Authors: Tudela Sergi , Coll Marta , Palomera Isabel 
Published: March 2005

Abstract
A composite quantitative index for the percentage of primary production required to sustain fisheries and the average trophic level of catch (%PPR–TLc) was employed to develop ecosystem-based reference functions suitable for fisheries management. Established ecosystem models, characterized by pairs of %PPR–TLc, were classified as either sustainably exploited or ecosystem overfished, on the basis of the results of factorial correspondence analysis applied to selected ecological indices, and on information from various sources. Canonical discriminant analysis of these pairs was applied to establish the discriminant function to separate the two exploitation classes. Next, reference functions related to different probabilities of ecosystem overfishing were developed to obtain an operational framework for ecosystem-based fisheries management. Values of ecosystem-based maximum sustainable catches associated with different probabilities of belonging to a sustainable situation were calculated. Overall, results show that most current fishing scenarios entail high risks of ecosystem overfishing.
The Lucid Dream Ensemble: a laboratory of discovery in the age of convergence
Authors: MOOREFIELD VIRGIL , WEETER JEFFREY 
Published: March 2005

This paper describes the formation, creations and performances of a digital arts performing ensemble. It considers issues of collaboration across media, especially in the context of composed audio-visual improvisation (comprovisation). By contextualising our creative work within the wider discourse of both the practice and aesthetics of contemporary intermedia, we seek to enhance the potential relevancy of the article's main focus to readers.The story of the Lucid Dream Ensemble is one of contemporary creative activity in the realm of digital arts. It exists in a university setting, and its purpose is educational as well as artistic. Founded at Northwestern University in Evanston, Illinois in 2002, the ensemble seeks to foster collaboration across auditory and visual boundaries. The group is made up of audio-visual performers who control laptop computers in real-time by various interactive means. Its canvas is a surround-sound set-up, as well as three projectors. The ensemble seeks a true integration of video and audio, as expressed in the creation of audio-visual artefacts aimed at providing an immersive experience. The group has progressed from presenting unrelated audio and video, to integrating the process of creation of sound and image, to collecting audio and video as a group and processing them collaboratively.
Racecadotril demonstrates intestinal antisecretory activity in vivo
Authors: Primi M.P. , Bueno L. , Baumer P. , Berard H. , Lecomte J.M. 
Published: March 2005

Background Racecadotril (acetorphan), a potent enkephalinase inhibitor, protects endogenous enkephalins from degradation. Racecadotril exhibits experimental and clinical antidiarrhoeal activity without any effect on intestinal motility, suggesting selective antisecretory activity. The antisecretory effect of racecadotril was directly assessed in the present study. Methods A 1 m, jejunal, Thiry–Vella loop was created in six mongrel dogs, and water and ionic fluxes were evaluated during infusion (2 mL/min) of Tyrode solution labelled with 14C‐polyethylene glycol. Fluxes were determined both in the basal state and 5–6 h after commencement of a 2‐h infusion of cholera toxin (0.4 μg/mL). Racecadotril (10 mg/kg) or vehicle was given orally with and without prior intravenous administration of naloxone (0.1 mg/kg) or phentolamine (0.2 mg/kg). Results Basal absorption remained unchanged following racecadotril administration; however, racecadotril significantly decreased (P = 0.01) cholera toxin‐induced water, sodium, and potassium hypersecretion, from 0.73 ± 0.15 to 0.37 ± 0.13 mL/min; from 125.0 ± 16.1 to 14.7 ± 9.5 μMol/min; and from 3.41 ± 0.66 to 1.66 ± 0.61 μMol/min, respectively. This antisecretory activity of racecadotril was suppressed by naloxone but not by phentolamine. Conclusions This study directly demonstrates the antisecretory activity of racecadotril in relation to the protection of endogenous enkephalins.
The Irish Affected Sib Pair Study of Alcohol Dependence: Study Methodology and Validation of Diagnosis by Interview and Family History
Authors: Prescott Carol A. , Sullivan Patrick F. , Myers John M. , Patterson Diana G. , Devitt Margaret , Halberstadt Lisa J. , Walsh Dermot , Kendler Kenneth S. 
Published: March 2005

Background:This article is the first report of the Irish Affected Sib Pair Study of Alcohol Dependence, whose goal is to detect the genomic location of susceptibility loci for alcohol dependence (AD). This article describes phenotypic characteristics of the probands, siblings, and parents included in the sample and examines agreement among different sources of diagnostic information, including the validity of family history (FH) assessment.Methods:Structured diagnostic interviews were conducted with 1414 individuals from 591 families ascertained in Ireland. AD was assessed among 1201 probands and affected siblings with use of the Semi‐Structured Assessment for the Genetics of Alcoholism and among 213 parents with use of a modified version of the Structured Clinical Interview for DSM. Probands and siblings were also assessed for drinking history, comorbid disorders, and other clinical characteristics. FH reports based on FH‐Research Diagnostic Criteria were obtained for 1113 of these individuals as well as for 3652 first‐degree relatives who were not interviewed.Results:Sample characteristics confirm the severity of AD among the affected individuals. Agreement between FH ratings and diagnoses based on direct interviews was high for both parent‐offspring and sibling‐sibling comparisons (e.g., positive and negative predictive values > 80% for a range of cutoffs). Agreement among individuals about their family members was also high for a single item (1 month or more of drinking problems, tetrachoric r= 0.86–0.98), the total number of DSM‐IV AD symptoms (polychoric r= 0.86–0.96), and classifications based on a range of cutoffs (κ= 0.75–0.80). Use of multiple informants improved classification accuracy only slightly (6–10%).Conclusions:The authors successfully collected data for a large sample of affected sibling pairs for molecular genetic analysis of AD. Individuals with AD were able to provide accurate evaluations of alcoholism symptoms in their parents and adult siblings. A single screening item performed nearly as well as the full scale. Collecting information from multiple informants may not be cost effective for the gain in predictive accuracy. FH information collected from affected informants can be a valuable source of diagnostic information for family studies of alcoholism.
Sex Difference in Nitric Oxide Synthase–Dependent Dilatation of Cerebral Arterioles During Long‐Term Alcohol Consumption
Authors: Sun Hong , Mayhan William G. 
Published: March 2005

Background:Although long‐term alcohol consumption impairs both endothelial nitric oxide synthase (NOS) (eNOS)–dependent and neuronal NOS (nNOS)–dependent reactivity of cerebral arterioles in male rats, the influence of sex on alcohol consumption–induced impairment of NOS–dependent cerebral vasodilation has not been examined. Therefore, the authors’ first goal was to determine whether long‐term alcohol consumption alters eNOS‐dependent and nNOS‐dependent reactivity of pial arterioles in female rats. Their second goal was to examine potential mechanisms for impaired responses of pial arterioles during long‐term alcohol consumption.Methods:Male and female rats were fed liquid diets with or without alcohol for 2–3 months. The authors measured the in vivo diameter of pial arterioles in response to eNOS‐dependent agonists (acetylcholine and ADP), nNOS‐dependent agonists (kainate and NMDA), and NOS–independent agonists (nitroglycerin and diethylaminodiazen (NONOate)) in the absence and presence of tetrahydrobiopterin (BH4).Results:Topical application of acetylcholine (1.0 and 10 μM), ADP (10 and 100 μM), kainate (100 and 300 μM), and NMDA (100 and 300 μM) produced dose‐related dilatation of pial arterioles. However, the magnitude of vasodilation in response to acetylcholine and ADP was significantly less in alcohol‐fed male and female rats, and the magnitude of vasodilation in response to kainate and NMDA was significantly less in alcohol‐fed male rats. Nitroglycerin and NONOate produced similar vasodilation in non–alcohol‐fed and alcohol‐fed male and female rats. Application of BH4 did not alter vasodilation in non–alcohol‐fed rats but improved impaired eNOS‐dependent vasodilation in alcohol‐fed male and female rats.Conclusions:Our findings suggest that long‐term alcohol consumption impairs eNOS‐dependent but not nNOS‐dependent dilatation of cerebral arterioles in female rats and that impaired eNOS‐dependent vasodilation may be related to a deficiency or alteration in the utilization of BH4.