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Terms modified by Filtered Selected AbstractsDietary protein requirements of juvenile haddock (Melanogrammus aeglefinus L.)AQUACULTURE RESEARCH, Issue 2001J D Kim Abstract A study was conducted to determine growth and feed utilization by haddock fed diets containing graded levels of protein (35, 40, 45 and 50%). Haddock fingerlings with an average weight of 24 g were hand-fed one of the four isoenergetic (,16.6 MJ digestible energy kg,1) experimental diets to satiation, three times a day during the 9-week period. Filtered and UV-treated water (salinity, 30,) was supplied to each circular tank (holding capacity: 320 L) at 4 L min,1 in a flow-through system. Increases in dietary protein improved weight gain, specific growth rate (SGR) and feed : gain ratio. The highest weight gain (percentage/initial weight) was observed in fish fed 50% protein, although there was no significant difference between groups fed 45% and 50% protein. A similar effect was observed in SGR of fish fed 50% protein, which was the highest among treatments. Although an increase in dietary protein resulted in a slight increase in feed intake, the lowest feed : gain ratio was obtained in fish fed the diet with the highest protein. Nitrogen intake increased from 1.48 to 2.33 g with the increase in dietary protein levels, which resulted in an improvement in whole-body nitrogen gain, although there were no significant differences in nitrogen retention and protein efficiency ratio among fish groups. The broken-line regression of weight gain against protein level yielded an estimated protein requirement of 49.9%. [source] Enhancing Neural Network Traffic Incident-Detection Algorithms Using WaveletsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2001A. Samant Researchers have presented freeway traffic incident-detection algorithms by combining the adaptive learning capability of neural networks with imprecision modeling capability of fuzzy logic. In this article it is shown that the performance of a fuzzy neural network algorithm can be improved through preprocessing of data using a wavelet-based feature-extraction model. In particular, the discrete wavelet transform (DWT) denoising and feature-extraction model proposed by Samant and Adeli (2000) is combined with the fuzzy neural network approach presented by Hsiao et al. (1994). It is shown that substantial improvement can be achieved using the data filtered by DWT. Use of the wavelet theory to denoise the traffic data increases the incident-detection rate, reduces the false-alarm rate and the incident-detection time, and improves the convergence of the neural network training algorithm substantially. [source] Phase-rotation in in-vivo localized spectroscopyCONCEPTS IN MAGNETIC RESONANCE, Issue 3 2007Saadallah Ramadan Abstract Phase-rotation is an alternative method to phase-cycling in acquisition of magnetic resonance spectroscopic data. However, there has only been two papers describing its implementation in point resolved spectroscopy (PRESS) and stimulated echo acquisition mode (STEAM) to date. This article aims to introduce and explain the principles of phase-rotation, describe the implementations that were carried out so far in the current literature, compare phase-rotation and phase-cycling experimentally, and introduce the application of phase-rotation in double-quantum filtered (DQF) spectroscopy. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part A 30A: 147,153, 2007 [source] Na+/H+ exchangers and the regulation of volumeACTA PHYSIOLOGICA, Issue 1-2 2006R. T. Alexander Abstract The regulation of volume is fundamental to life. There exist numerous conditions that can produce perturbations of cell volume. The cell has developed mechanisms to directly counteract these perturbations so as to maintain its physiological volume. Directed influx of the major extracellular cation, sodium, serves to counteract a decreased cell volume through the subsequent osmotically coupled movement of water to the intracellular space. This process, termed regulatory volume increase is often mediated by the ubiquitous sodium/hydrogen ion exchanger, NHE1. Similarly, the maintenance of intravascular volume is essential for the maintenance of blood pressure and consequently the proper perfusion of vital organs. Numerous mechanisms exist to counterbalance alterations in intravascular volume, not the least of which is the renal absorption of sodium filtered at the glomerulus. Two-thirds of filtered sodium and water are absorbed in the renal proximal tubule, a mechanism that intimately involves the apical sodium/hydrogen ion exchanger, NHE3. This isoform is fundamental to the maintenance and regulation of intravascular volume and blood pressure. In this article, the effects of cell volume on the activity of these different isoforms, NHE1 and NHE3, will be described and the consequences of their activity on intracellular and intravascular volume will be explored. [source] Short and long term consequences of increases in exotic species richness on water filtration by marine invertebratesECOLOGY LETTERS, Issue 8 2009Jarrett Byrnes Abstract Although recent research has considered the consequences of global declines in the number of species, less attention has focused on the aggregate effects of regional increases in species richness as a result of human-mediated introductions. Here we examine several potential ecosystem consequences of increasing exotic species diversity of suspension feeding marine invertebrates. First, we experimentally manipulated native and non-native suspension feeder richness and measured its effect on short-term phytoplankton clearance rates. Multispecies communities all performed similarly, regardless of whether they were dominated by natives, exotics, or an even mix of the two. Individual species varied considerably in filtration rates, but non-native species often filtered less than the most similar native. Second, we determined potential changes in integrated function over time by comparing seasonal patterns of recruitment as a proxy for the ability to quickly recover filtration capacity after a disturbance. We found that exotic species have complementary seasonal phenologies both to native species and each other. Our results suggest that the consequences of local increases in species richness due to invasions may be manifest over long (annual to interannual) time scales, even when short term changes in ecosystem function are negligible. [source] Consistent High-precision Volatility from High-frequency DataECONOMIC NOTES, Issue 2 2001Fulvio Corsi Estimates of daily volatility are investigated. Realized volatility can be computed from returns observed over time intervals of different sizes. For simple statistical reasons, volatility estimators based on high-frequency returns have been proposed, but such estimators are found to be strongly biased as compared to volatilities of daily returns. This bias originates from microstructure effects in the price formation. For foreign exchange, the relevant microstructure effect is the incoherent price formation, which leads to a strong negative first-order autocorrelation ,(1),40 per cent for tick-by-tick returns and to the volatility bias. On the basis of a simple theoretical model for foreign exchange data, the incoherent term can be filtered away from the tick-by-tick price series. With filtered prices, the daily volatility can be estimated using the information contained in high-frequency data, providing a high-precision measure of volatility at any time interval. (J.E.L.: C13, C22, C81). [source] Extracellular phosphatase activity of natural plankton studied with ELF97 phosphate: fluorescence quantification and labelling kineticsENVIRONMENTAL MICROBIOLOGY, Issue 6 2003í Nedoma Summary ELF®97 phosphate (ELFP) is a phosphatase substrate which produces ELF®97 alcohol (ELFA), a fluorescent water-insoluble product, upon hydrolysis. We studied the kinetics of ELFA precipitation in freshwater samples at levels of total plankton and single phytoplankton cells, and tested the suitability of ELFP for measurement of surface-bound algal extracellular phosphatases. Samples from acidic Ple,né Lake (pH , 5; high phosphatase activity) and eutrophic ,ímov reservoir (pH ,7,10; moderate phosphatase activity) were incubated with ELFP for 5,300 min, fixed with HgCl2 and filtered through polycarbonate filters. Relative fluorescence of filter-retained ELFA precipitates was quantified with image analysis. Time-courses of ELFA formation exhibited lag periods followed by finite periods of linear increase. In Ple,né Lake, lag-times were shorter (1,18 min) and rates of increase in ELFA fluorescence higher (by ,2 orders of magnitude) than in ,ímov reservoir (lag-times 30,200 min). Similar patterns of ELFA formation kinetics were also observed in Ple,né Lake samples in cuvette spectrofluorometer measurements (which failed in ,ímov reservoir). Linear regression of seasonal data on rates of increase in ELFA fluorescence from image cytometry and spectrofluorometry (r2 = 0.65, n = 10) allowed for calibration of image cytometry in terms of amount of cell-associated ELFA. Preliminary measurements of extracellular phosphatase activities of several algae resulted in rates (10,2260 fmol cell,1 h,1) which are comparable to data reported in the literature for algal cultures. [source] Masticatory performance in patients with anterior disk displacement without reduction in comparison with symptom-free volunteersEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2002Ingrid Peroz Masticatory function can be impaired by craniomandibular disorders. The aim of this study was to assess masticatory performance in patients with an anterior disc displacement (ADD) without reduction. In the experiments, 29 patients and 33 age- and gender-matched volunteers chewed artificial test food for 60 chewing strokes. The collected remains of the test food were filtered, dried, fractionated by a sieving procedure, and weighed. The particle size distribution was then described using a cumulative distribution function. Patients and controls were clinically examined, and patients were asked to complete a pain questionnaire. Comparison with controls, patients showed significantly reduced masticatory performance. Patients that had had a disorder longer than 3 yr tended to display less reduction of their masticatory performance. Neither the treatment methods used, nor restriction of daily life activities or pain intensity were significantly correlated with masticatory performance. Jaw mobility was significantly reduced in patients. More than half of the patients and none of the controls had joint noises and trigger points in the masticatory muscles. Pain was present, in particular, during chewing and maximal opening of the mouth. It was concluded that patients with ADD without reduction have a significantly reduced masticatory performance. [source] Multivariate calibration of hyperspectral ,-ray energy spectra for proximal soil sensingEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 1 2007R. A. Viscarra Rossel Summary The development of proximal soil sensors to collect fine-scale soil information for environmental monitoring, modelling and precision agriculture is vital. Conventional soil sampling and laboratory analyses are time-consuming and expensive. In this paper we look at the possibility of calibrating hyperspectral ,-ray energy spectra to predict various surface and subsurface soil properties. The spectra were collected with a proximal, on-the-go ,-ray spectrometer. We surveyed two geographically and physiographically different fields in New South Wales, Australia, and collected hyperspectral ,-ray data consisting of 256 energy bands at more than 20 000 sites in each field. Bootstrap aggregation with partial least squares regression (or bagging-PLSR) was used to calibrate the ,-ray spectra of each field for predictions of selected soil properties. However, significant amounts of pre-processing were necessary to expose the correlations between the ,-ray spectra and the soil data. We first filtered the spectra spatially using local kriging, then further de-noised, normalized and detrended them. The resulting bagging-PLSR models of each field were tested using leave-one-out cross-validation. Bagging-PLSR provided robust predictions of clay, coarse sand and Fe contents in the 0,15 cm soil layer and pH and coarse sand contents in the 15,50 cm soil layer. Furthermore, bagging-PLSR provided us with a measure of the uncertainty of predictions. This study is apparently the first to use a multivariate calibration technique with on-the-go proximal ,-ray spectrometry. Proximally sensed ,-ray spectrometry proved to be a useful tool for predicting soil properties in different soil landscapes. [source] The effect of hypoxia on pulmonary O2 uptake, leg blood flow and muscle deoxygenation during single-leg knee-extension exerciseEXPERIMENTAL PHYSIOLOGY, Issue 3 2004Darren S. DeLorey The effect of hypoxic breathing on pulmonary O2 uptake (VO2p), leg blood flow (LBF) and O2 delivery and deoxygenation of the vastus lateralis muscle was examined during constant-load single-leg knee-extension exercise. Seven subjects (24 ± 4 years; mean ±s.d.) performed two transitions from unloaded to moderate-intensity exercise (21 W) under normoxic and hypoxic (PETO2= 60 mmHg) conditions. Breath-by-breath VO2p and beat-by-beat femoral artery mean blood velocity (MBV) were measured by mass spectrometer and volume turbine and Doppler ultrasound (VingMed, CFM 750), respectively. Deoxy-(HHb), oxy-, and total haemoglobin/myoglobin were measured continuously by near-infrared spectroscopy (NIRS; Hamamatsu NIRO-300). VO2p data were filtered and averaged to 5 s bins at 20, 40, 60, 120, 180 and 300 s. MBV data were filtered and averaged to 2 s bins (1 contraction cycle). LBF was calculated for each contraction cycle and averaged to 5 s bins at 20, 40, 60, 120, 180 and 300 s. VO2p was significantly lower in hypoxia throughout the period of 20, 40, 60 and 120 s of the exercise on-transient. LBF (l min,1) was approximately 35% higher (P > 0.05) in hypoxia during the on-transient and steady-state of KE exercise, resulting in a similar leg O2 delivery in hypoxia and normoxia. Local muscle deoxygenation (HHb) was similar in hypoxia and normoxia. These results suggest that factors other than O2 delivery, possibly the diffusion of O2, were responsible for the lower O2 uptake during the exercise on-transient in hypoxia. [source] Survival of Escherichia coli O157:H7 in private drinking water wells: influences of protozoan grazing and elevated copper concentrationsFEMS MICROBIOLOGY LETTERS, Issue 1 2002Rebekka R.E Artz Abstract The survival characteristics of Escherichia coli O157:H7 in private drinking water wells were investigated to assess the potential for human exposure. A non-toxigenic, chromosomally lux -marked strain of E. coli O157:H7 was inoculated into well water from four different sites in the North East of Scotland. These waters differed significantly in their heavy metal contents as well as nutrient and bacterial grazer concentrations. Grazing and other biological factors were studied using filtered (3 and 0.2 ,m) and autoclaved water. The survival of E. coli O157:H7 was primarily decreased by elevated copper concentrations. This hypothesis was supported by acute toxicity assay data. In addition, significant protozoan predation effects were observed in untreated water when compared with survival rates in filtered water. The combination of these two factors in particular determines the survival time of the pathogen in a private water well. It therefore appears that wells with higher water quality as assessed using the European Union Drinking Water Directive standards will also allow survival of E. coli O157:H7 for much longer periods. [source] A Geostatistical Analysis of Soil, Vegetation, and Image Data Characterizing Land Surface VariationGEOGRAPHICAL ANALYSIS, Issue 2 2007Sarah E. Rodgers The elucidation of spatial variation in the landscape can indicate potential wildlife habitats or breeding sites for vectors, such as ticks or mosquitoes, which cause a range of diseases. Information from remotely sensed data could aid the delineation of vegetation distribution on the ground in areas where local knowledge is limited. The data from digital images are often difficult to interpret because of pixel-to-pixel variation, that is, noise, and complex variation at more than one spatial scale. Landsat Thematic Mapper Plus (ETM+) and Satellite Pour l'Observation de La Terre (SPOT) image data were analyzed for an area close to Douna in Mali, West Africa. The variograms of the normalized difference vegetation index (NDVI) from both types of image data were nested. The parameters of the nested variogram function from the Landsat ETM+ data were used to design the sampling for a ground survey of soil and vegetation data. Variograms of the soil and vegetation data showed that their variation was anisotropic and their scales of variation were similar to those of NDVI from the SPOT data. The short- and long-range components of variation in the SPOT data were filtered out separately by factorial kriging. The map of the short-range component appears to represent the patterns of vegetation and associated shallow slopes and drainage channels of the tiger bush system. The map of the long-range component also appeared to relate to broader patterns in the tiger bush and to gentle undulations in the topography. The results suggest that the types of image data analyzed in this study could be used to identify areas with more moisture in semiarid regions that could support wildlife and also be potential vector breeding sites. [source] EXPANSION OF GOLF COURSES IN THE UNITED STATES,GEOGRAPHICAL REVIEW, Issue 1 2008DARRELL E. NAPTON ABSTRACT. Twenty-five million Americans play golf on the nation's 16,000 courses each year. These golf courses constitute a significant national landscape feature. Since 1878, when the game arrived in the United States, golf has filtered down the urban, economic, and social hierarchies to become accepted by and accessible to most Americans. During the ensuing thirteen decades the number, location, and layout of the nation's golf courses have responded to many of the same driving forces that impacted the nation, including decentralization, growth of the middle class, war, economic depression, suburbanization, and the increasing role of the federal government. Four epochs of golf-course growth and diffusion show the growing acceptance of the sport and depict where courses were most likely to be constructed as a result of the prevailing forces of each epoch. [source] Absolute S -velocity estimation from receiver functionsGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 3 2007L. Svenningsen SUMMARY We present a novel method to recover absolute S velocities from receiver functions. For a homogeneous half-space the S velocity can be calculated from the horizontal slowness and the angle of surface particle motion for an incident P wave. Generally, the calculated S velocity is an apparent half-space value which depends on model inhomogeneity and P -waveform. We therefore, suggest to calculate such apparent half-space S velocities from low-pass filtered (smoothed) receiver functions using a suite of filter-parameters, T. The use of receiver functions neutralize the influence of the P -waveform, and the successive low-pass filterings emphasize the variation of S velocity with depth. We apply this VS,app.(T) technique to teleseismic data from three stations: FUR, BFO and SUM, situated on thick sediments, bedrock and the Greenland ice cap, respectively. The observed VS,app.(T) curves indicate the absolute S velocities from the near surface to the uppermost mantle beneath each station, clearly revealing the different geological environments. Application of linearized, iterative inversion quantify these observations into VS(z) models, practically independent of the S -velocity starting model. The obtained models show high consistency with independent geoscientific results. These cases provide also a general validation of the VS,app.(T) method. We propose the computation of VS,app.(T) curves for individual three-component broad-band stations, both for direct indication of the S velocities and for inverse modelling. [source] Family and nation: Brazilian national ideology as contested transnational practice in JapanGLOBAL NETWORKS, Issue 4 2008PAUL GREEN Abstract Studies of Brazilian Nikkeis (Japanese emigrants and their descendants) living in Japan tend to conceptualize ,family' and ,nation' as two distinct entities. Such distinctions are filtered through mutually exclusive discourses and understandings of national and ethnic identity. In this article, however, I view national attachments and migrant experiences in Japan through the lens of ideology, embodied experience and kinship relations. Treating national ideology as lived process sheds fresh light on the dynamics of state,society relations in transnational social spaces. I suggest that the ability of Brazilian state actors to impose social, moral and economic regulation on its citizens in Japan is compromised by the extent to which such discourses are ontologically grounded in the social relations of migrant family life. It is through these kin ties, I argue, that people set the tone and rules of play for state interests to encroach or otherwise on their everyday lives in these transnational social spaces. [source] Voices in court: lawyers' or litigants'?HISTORICAL RESEARCH, Issue 186 2001Joanne Bailey Written records of litigation lie at the heart of numerous studies of English society and culture. Although some documents appear to demonstrate individuality, historians advise that they be used cautiously since the words of litigants and deponents were filtered through the legal profession. This article uncovers the process of mediation by exploring the interaction between litigants and their legal advisers, using correspondence received by church court proctors. It reveals that some parties had an active role in their litigation and, crucially, that their own motives could obscure the reality underlying their lawsuits as much as the legal process. [source] Attentional load modifies early activity in human primary visual cortexHUMAN BRAIN MAPPING, Issue 5 2009Karsten S. Rauss Abstract Recent theories of selective attention assume that the more attention is required by a task, the earlier are irrelevant stimuli filtered during perceptual processing. Previous functional MRI studies have demonstrated that primary visual cortex (V1) activation by peripheral distractors is reduced by higher task difficulty at fixation, but it remains unknown whether such changes affect initial processing in V1 or subsequent feedback. Here we manipulated attentional load at fixation while recording peripheral visual responses with high-density EEG in 28 healthy volunteers, which allowed us to track the exact time course of attention-related effects on V1. Our results show a modulation of the earliest component of the visual evoked potential (C1) as a function of attentional load. Additional topographic and source localization analyses corroborated this finding, with significant load-related differences observed throughout the first 100 ms post-stimulus. However, this effect was observed only when stimuli were presented in the upper visual field (VF), but not for symmetrical positions in the lower VF. Our findings demonstrate early filtering of irrelevant information under increased attentional demands, thus supporting models that assume a flexible mechanism of attentional selection, but reveal important functional asymmetries across the VF. Hum Brain Mapp 2009. © 2008 Wiley-Liss, Inc. [source] Preen waxes do not protect carotenoid plumage from bleaching by sunlightIBIS, Issue 2 2008ADRIAN SURMACKI The plumage coloration of wild birds often changes during the breeding season. One of the possible reasons for this is that sunlight, and particularly ultraviolet (UV) wavelengths, degrades the pigments responsible for plumage coloration. It has been suggested that birds may apply preen wax to feathers to protect feathers from bleaching. This hypothesis is tested by exposing carotenoid-based breast feathers of Great Tits to ambient light, light filtered to exclude UV and darkness. Preen waxes were experimentally removed from feather samples and the effect of light on coloration of treatment and control feathers compared. Ambient light had an effect on feather colour but preen wax did not. Feathers exposed to sun gradually became less saturated and hues shifted towards shorter wavelengths. This was not apparent in control feathers kept in darkness. Feathers exposed to full-spectra sunlight faded more than those that were kept in light with UV wavelengths removed. There was a decrease in brightness of feathers in both experimental and control groups, which was assumed to be an effect of dirt accumulation. This experiment confirmed earlier suspicions regarding the detrimental effects of UV irradiation on carotenoid-based coloration of avian feathers but failed to show any protective function of preen waxes. The possible consequences of these mechanisms of colour change for birds with regard to mating strategies are discussed. [source] Changes in the timing of spring and autumn migration in North American migrant passerines during a period of global warmingIBIS, Issue 2 2005ALEXANDER M. MILLS Butler (2003) used first arrival dates (FADs) of 103 migrant birds in northeastern USA and found that both long-distance migrants (LDMs; wintering south of the USA) and short-distance migrants (SDMs; wintering in the southern USA) arrived earlier in the second half of the 20th century than they had in the first, consistent with scenarios of global warming; the trend was stronger in SDMs. Using FADs to characterize migration systems can be problematic because they are data from one tail of a distribution, they comprise a mostly male population and they may not correlate well with the balance of the migration period. FADs also provide no information about autumn migration. This paper uses a banding dataset from Long Point Bird Observatory, Ontario, for 14 passerines for a period of global warming (1975,2000), taking these issues into account. The data were filtered to minimize effects of unequal netting effort (147 491 resulting records), and the passage dates then calculated in each season of each year for the 1st, 2nd and 3rd quartiles for regression analysis. Only two of 13 species analysed in the spring showed significantly earlier passage times, although the overall trend was towards earlier spring migration, especially among SDMs. Autumn responses were more prevalent, however, and in some cases more dramatic with six of 13 species showing delayed migration (four SDMs, two LDMs). Two LDMs exhibited earlier autumn migration. Where earlier spring migration occurred, both sexes appeared to contribute to the change. Where delayed migration occurred in autumn, both sexes and both adults and hatch-year birds appeared to contribute in at least some cases. The spring FAD results are consistent with those of Butler, but when the whole migration is considered, change is far from universal in spring and is in fact more substantial and complex in autumn. [source] Determination of phthalate esters in cosmetics by gas chromatography with flame ionization detection and mass spectrometric detectionINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 4 2005Huiming Chen GC-FID; GC-MS; Produits cosmétiques; Esters Phtaliques Synopsis A gas chromatography coupled with flame ionization detection (GC-FID) and mass spectrometric detection (MSD) method was developed to determine the six kinds of phthalate esters [dimethyl phthalate (DMP), diethyl phthalate (DEP), di- n -butyl phthalate (DBP), benzyl butyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP) and di- n -octyl phthalate (DOP)] in cosmetics (solid, cream and liquid cosmetics). The cosmetics were extracted with methanol by ultrasonic and then separated with high-speed centrifugation. The upper clear layer was dried and filtered through a 0.45 ,m pore diameter filter. The filtrate was injected into GC-FID/GC-MS for detection. GC-FID chromatogram was applied for qualitative analysis, external standard method was used for quantitative analysis. Confirmation of phthalate presence was undertaken by GC-EI-MS. The recovery range of all phthalates were between 92.0 and 110.0% with relative standard deviations between 1.95 and 5.92%. The low detection limits of the method were: 0.1 ng for DMP, DEP, DBP and BBP, 0.5 ng for DEHP and DOP. The method had advantages of high precision and sensitivity, simplicity of pretreatment. The method can be used to test the six kinds of phthalate esters in cosmetics. Resume Une méthode d'analyse par chromatographie gazeuse couplée à une détection par ionization de flamme (GC - FID) et une détection spectrométrique de masse (MSD) a été développée pour analyser 6 sortes d'esters phtaliques (phtalate de diméthyle (DMP), phtalate de diéthyle (DEP), phtalate de di- n -butyle (DBP), phtalate de benzylbutyle (BBP), phtalate de di-2-éthylhexyle (DEHP) et phtalate de di- n -octyle (DOP)) dans des produits cosmétiques (solides, crèmes et liquides). Les produits cosmétiques sont extraits au méthanol sous ultrason, puis séparés par ultracentrifugation. La phase supérieure limpide est déshydratée et filtrée sur un filtre de diamètre de pore moyen égal à 0,45 ,m. Le filtrat est injecté dans le système GC - FID/GC-MS pour analyse. Les chromatogrammes GC-FID sont utilisés pour l'analyse qualitative, des standards externes ont été utilisés pour l'analyse quantitative. La GC-EI-MS permet de confirmer la présence des esters phtaliques. Le taux de récupération de tous les esters est compris entre 92 et 110% avec une déviation standard allant de 1,95%à 5,92%. La limite de détection par cette méthode est de 0,1 ng pour DMP, DEP, DBP et BBP, 0,5 ng pour DEHP et DOP. Les avantages de cette méthode sont sa haute précision, sa sensibilité et la simplicité du prétraitement. Cette méthode peut être utilisée pour doser la présence des six sortes d'esters phtaliques dans des produits cosmétiques. [source] Neoliberalism, Contingency and Urban Policy: The Case of Social Housing in OntarioINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 3 2006JASON HACKWORTH Various authors have argued that common understandings of neoliberalism are flawed because they do not adequately account for its geographical contingency or internal contradictions. Many have suggested that neoliberalism is either too internally riven with contradiction to be considered a singular consistent project, or that its implementation is so locally contingent that we cannot plausibly speak of one ideal-type placeless ideology. Primarily based on interviews with over half of the municipal housing providers in Ontario, this article explores the extent to which the meta-ideas of neoliberalism are filtered and manifest (or not) locally. Social policy has been neoliberalized in Ontario at least since the advent of the ,common sense revolution' in 1995, when a Tory government was elected on a platform of neoliberal reform. The experience of social housing in the province, before, after and during the transition offers a useful window into the debate about the dissonance (or lack thereof) between ideal-type and contingent neoliberalism. Based on this case, we argue that, despite its obvious conceptual flaws, it is politically and analytically important to understand ideal-type neoliberalism better. [source] Nordic rattle: the hoarse vocalization and the inflatable laryngeal air sac of reindeer (Rangifer tarandus)JOURNAL OF ANATOMY, Issue 2 2007Roland Frey Abstract Laryngeal air sacs have evolved convergently in diverse mammalian lineages including insectivores, bats, rodents, pinnipeds, ungulates and primates, but their precise function has remained elusive. Among cervids, the vocal tract of reindeer has evolved an unpaired inflatable ventrorostral laryngeal air sac. This air sac is not present at birth but emerges during ontogenetic development. It protrudes from the laryngeal vestibulum via a short duct between the epiglottis and the thyroid cartilage. In the female the growth of the air sac stops at the age of 2,3 years, whereas in males it continues to grow up to the age of about 6 years, leading to a pronounced sexual dimorphism of the air sac. In adult females it is of moderate size (about 100 cm3), whereas in adult males it is large (3000,4000 cm3) and becomes asymmetric extending either to the left or to the right side of the neck. In both adult females and males the ventral air sac walls touch the integument. In the adult male the air sac is laterally covered by the mandibular portion of the sternocephalic muscle and the skin. Both sexes of reindeer have a double stylohyoid muscle and a thyroepiglottic muscle. Possibly these muscles assist in inflation of the air sac. Head-and-neck specimens were subjected to macroscopic anatomical dissection, computer tomographic analysis and skeletonization. In addition, isolated larynges were studied for comparison. Acoustic recordings were made during an autumn round-up of semi-domestic reindeer in Finland and in a small zoo herd. Male reindeer adopt a specific posture when emitting their serial hoarse rutting calls. Head and neck are kept low and the throat region is extended. In the ventral neck region, roughly corresponding to the position of the large air sac, there is a mane of longer hairs. Neck swelling and mane spreading during vocalization may act as an optical signal to other males and females. The air sac, as a side branch of the vocal tract, can be considered as an additional acoustic filter. Individual acoustic recognition may have been the primary function in the evolution of a size-variable air sac, and this function is retained in mother,young communication. In males sexual selection seems to have favoured a considerable size increase of the air sac and a switch to call series instead of single calls. Vocalization became restricted to the rutting period serving the attraction of females. We propose two possibilities for the acoustic function of the air sac in vocalization that do not exclude each other. The first assumes a coupling between air sac and the environment, resulting in an acoustic output that is a combination of the vocal tract resonance frequencies emitted via mouth and nostrils and the resonance frequencies of the air sac transmitted via the neck skin. The second assumes a weak coupling so that resonance frequencies of the air sac are lost to surrounding tissues by dissipation. In this case the resonance frequencies of the air sac solely influence the signal that is further filtered by the remaining vocal tract. According to our results one acoustic effect of the air sac in adult reindeer might be to mask formants of the vocal tract proper. In other cervid species, however, formants of rutting calls convey essential information on the quality of the sender, related to its potential reproductive success, to conspecifics. Further studies are required to solve this inconsistency. [source] Conservation strategy maps: a tool to facilitate biodiversity action planning illustrated using the heath fritillary butterflyJOURNAL OF APPLIED ECOLOGY, Issue 2 2003G. J. Holloway Summary 1.,The UK Biodiversity Action Plan (UKBAP) identifies invertebrate species in danger of national extinction. For many of these species, targets for recovery specify the number of populations that should exist by a specific future date but offer no procedure to plan strategically to achieve the target for any species. 2.,Here we describe techniques based upon geographic information systems (GIS) that produce conservation strategy maps (CSM) to assist with achieving recovery targets based on all available and relevant information. 3.,The heath fritillary Mellicta athalia is a UKBAP species used here to illustrate the use of CSM. A phase 1 habitat survey was used to identify habitat polygons across the county of Kent, UK. These were systematically filtered using relevant habitat, botanical and autecological data to identify seven types of polygon, including those with extant colonies or in the vicinity of extant colonies, areas managed for conservation but without colonies, and polygons that had the appropriate habitat structure and may therefore be suitable for reintroduction. 4.,Five clusters of polygons of interest were found across the study area. The CSM of two of them are illustrated here: the Blean Wood complex, which contains the existing colonies of heath fritillary in Kent, and the Orlestone Forest complex, which offers opportunities for reintroduction. 5.,Synthesis and applications. Although the CSM concept is illustrated here for the UK, we suggest that CSM could be part of species conservation programmes throughout the world. CSM are dynamic and should be stored in electronic format, preferably on the world-wide web, so that they can be easily viewed and updated. CSM can be used to illustrate opportunities and to develop strategies with scientists and non-scientists, enabling the engagement of all communities in a conservation programme. CSM for different years can be presented to illustrate the progress of a plan or to provide continuous feedback on how a field scenario develops. [source] On detrending and cyclical asymmetryJOURNAL OF APPLIED ECONOMETRICS, Issue 3 2003Zacharias Psaradakis This paper considers the issue of testing for symmetry of the business cycle. It is demonstrated that findings of symmetry should be interpreted with caution since tests tend to have low power to detect asymmetries when applied to data that have been filtered to isolate their stationary business-cycle component. This implies that asymmetries are likely to be detected in practice only when they are particularly prominent. An empirical application examines the properties of the cyclical component of real GDP for the G7 countries. Copyright © 2002 John Wiley & Sons, Ltd. [source] The effect of toluidine blue on the survival, dormancy and outer membrane porin proteins (OmpC and OmpF) of Salmonella typhimurium LT2 in seawaterJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2002R. Ozkanca Aims: To study the relationship between changes in the composition of the outer membrane proteins and the survival of Salmonella typhimurium LT2 in filtered autoclaved seawater containing Toluidine Blue (TB) dye as a photosensitizer. Methods and Results: In samples exposed to TB and excited by artificial visible light, the total viable (TVC) and respiring cell counts (RCC) showed that, although the TVC declined to an undetectable level in 6·5 h, the RCC showed that some cells were still capable of respiration. The porin protein composition changed gradually with OmpC and OmpF becoming undetectable by sodium dodecyl sulphate-polyacrylamide gel electrophoresis after 8 h of incubation. Hydrogen peroxide-pretreated cells survived longer compared with the control. Conclusions: Oxidative pretreatment of Salm. typhimurium protects cells from some of the effects of sunlight in the presence of photosensitizers. The changes in porin proteins may play a role in this protection. Significance and Impact of the Study: The study shows that the survival of bacteria under conditions of stress is the result of a linked series of reactions. [source] The Branchiopoda (Crustacea: Anomopoda, Ctenopoda and Cyclestherida) of the rain forests of Cameroon, West Africa: low abundances, few endemics and a boreal,tropical disjunctionJOURNAL OF BIOGEOGRAPHY, Issue 9 2005George Y. Chiambeng Abstract Aim, We provide the first in-depth study of the Branchiopoda of the rain forests of Cameroon and also of the African continent. Location, Surface water environments, Cameroon. Methods, Qualitative plankton samples were collected in all types of surface water environments present, ranging from big lakes to water collected in rock crevices or fallen fruit cavities. A tow or hand-held plankton net of mesh size 100 ,m was used, and water volumes filtered were at least several m3 in large water bodies, or half to whole water volume in small water bodies. Results, We recorded 61 species (53 first records for the country), based on 700+ samples collected between September 1998 and March 2002. Anomopoda (92%) was the dominant order, followed by Ctenopoda (6.5%) and Cyclestherida (1.5%). Chydoridae (67%) was the most speciose family followed by Macrothricidae (6.5%) and Daphniidae (5%). Alona (11%) was the dominant genus followed by Chydorus (10%) and Pleuroxus (8%). Several species of Chydorinae, especially of the genus Pleuroxus, are shared with continental Eurasia,North America, but are absent from the Mediterranean and desert,steppe,savanna zones of Africa (boreal,tropical disjunction). Daphnia was absent, as in most tropical lowlands. No single species was really abundant, and a majority were rare to very rare, and of restricted occurrence within the rain forest patches. Comparing Africa, South America and Southeast Asia, we found a current total of 196 species for the combined rain forest areas, out of a world total of 500+ species. Systematic trends in richness at three taxonomic levels were the same for all continents: Anomopoda,Ctenopoda,Cyclestherida at ordinal level, Chydoridae,Daphniidae,Macrothricidae,Sididae at family level and Alona,Chydorus,Macrothrix,Diaphanosoma at genus level. Southeast Asia was richest (111 species, 14 endemics) with South America a close second (110 species, 27 endemics). Africa was the most species-poor (95 species, of which only 5 are endemics). Main conclusions, We hypothesize that the post-Miocene cooling and aridization of the world climate hit the freshwater biota of Africa particularly hard, with more extinction here than elsewhere, and little recolonization. Most extinction occurred in the savanna-desert belt, and eight disjunct boreal species (four Pleuroxus, Picripleuroxus laevis, Kurzia latissima, Alonella exigua, and Monospilus dispar) survive morphologically unchanged since pre-Pleistocene times in the Cameroon rain forest. Slow evolution thus appears typical of these cyclic parthenogenetic branchiopods in which sexual recombination occurs only at intervals. Illustrative of the same slow evolution is the fact that the two endemic cladocerans of Cameroon (Nicsmirnovius camerounensis and Bryospilus africanus) belong to tropicopolitan genera of Gondwanan age. [source] Controlled application and removal of liposomal therapeutics: Effective elimination of pegylated liposomal doxorubicin by double-filtration plasmapheresis in vitroJOURNAL OF CLINICAL APHERESIS, Issue 2 2010Gerhard Pütz Abstract Introduction: Nanoscale particle-based drug delivery systems like long circulating liposomal doxorubicin show unique pharmacokinetic properties and improved toxicity profiles. Liposomal doxorubicin accumulates in tumor tissue due to the enhanced permeation and retention effect, but only a small fraction of a total dose reaches the tumor site. Accumulation of liposomal doxorubicin is much faster in tumor sites than in certain organs where dose limiting adverse effects occur. Finding a way to detoxify the predominant part of a given dose, circulating in the blood after accumulation is completed, will presumably reduce severe side effects during chemotherapy. Methods: Elimination properties of therapeutic used pegylated liposomal doxorubicin (Doxil®/Caelyx®) and therapeutic used double-filtration plasmapheresis systems were evaluated in vitro and in reconstituted human blood. Results: Liposomes can be filtered by appropriate membranes without leakage of doxorubicin up to a pressure of 1 bar. At higher pressures, liposomes (,85 nm) may squeeze through much smaller pores without significant leakage of doxorubicin, whereas decreasing pore size to ,8 nm leads to increased leakage of doxorubicin. With therapeutic used apheresis systems, liposomal doxorubicin can be efficiently eliminated out of buffer medium and reconstituted human blood. No leakage of doxorubicin was detected, even when liposomes were circulating for 48 h in human plasma before apheresis. Conclusions: Convenient apheresis techniques are capable of a safe and efficient elimination of therapeutic used liposomal doxorubicin in an experimental model system. J. Clin. Apheresis, 2010. © 2010 Wiley-Liss, Inc. [source] Assessment of spring water quality and quantity, and health implications in Tongaren division, Nzoia River catchment, KenyaAFRICAN JOURNAL OF ECOLOGY, Issue 2009G. M. Simiyu Abstract Spring water is the common source of public water supply in most rural communities of developing countries such as Kenya. The water quality and quantity may be altered due to catchments degradation. This study was carried out in Tongaren division, Nzoia River catchment. The aim of this study was to investigate and map the occurrence and distribution of springs and to determine their water quality and quantity. This study determined the spring water discharge, conductivity, turbidity, total and thermotolerant (faecal) coliforms to assess suitability and sustainability of spring water for safe drinking. Twenty-eight springs were identified and their locations mapped using Global Positioning System (GPS) geo-reference data. Discharge ranged from 0.1 to 3 l s,1, with some drying up during dry season. Total coliform was innumerable in most of the studied springs while thermotolerant (faecal) coliform counts occurred in eight springs, including four protected springs. This poses high risks of water-borne diseases. The water should be filtered and boiled prior to use for drinking. Facilitation of communities enabled development of seven springs to enhance water yield and quality. This study established high potential in the communities to develop springs and utilize the spring water as alternative source of livelihoods. [source] A systematic review and meta-synthesis: evaluating the effectiveness of nurse, midwife/allied health professional consultantsJOURNAL OF CLINICAL NURSING, Issue 10 2007Ann Humphreys PhD, Cert Ed Aim., This paper presents the findings of a systematic review and meta-synthesis, which was undertaken to identify and assess studies that evaluated the nurse/midwife/allied health professional consultant role. Background., As part of the modernization agenda in the National Health Service the United Kingdom government proposed ,Consultant' posts for nurses/midwives and allied health professionals as an opportunity for experienced practitioners to extend their roles. Four key functions were identified as being significant to this role development: expert practice, leadership, education and research. Explicit within the proposal was a requirement of these new roles to be evaluated. Method., Inclusion criteria focussed on studies where an aspect of the role had been evaluated or where the consultant carried out the research. A total of 1931 citations was filtered to reveal 107 studies that possibly met the inclusion criteria. Of these 107, 14 studies were critically appraised and subjected to thematic analysis. Study methodology varied but of the 14 studies, 10 involved some form of measurement. The others adopted a literature review or descriptive approach. Conclusions., The extent to which consultants were involved in all aspects of the ,four pillars' was assessed in only a small number of studies. However, a number of studies implicitly implied active engagement in expert practice and leadership by focussing on specific service developments. Relevance to clinical practice., To date, a number of studies evaluating service developments, education, expert practice and leadership have been carried out. However although a number of studies have assessed perceived impact of the consultant role, no measure of actual benefit has been published to date. Studies that evaluate the cost benefit/outcomes of these roles in relation to both activity and quality of service are required. [source] Particulate contamination of lyophilized amphotericin B preparation during reconstitution processJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 2 2001T. Sendo Objective:,To investigate the effect of the reconstitution methods for the commercial amphotericin B preparation with respect to particulate contamination. Methods:,The particle counts in amphotericin B solutions reconstituted according to three different methods and amphotericin B fluids made with intravenous fluids after reconstitution were performed using a light extinction method. The particle contaminants were identified with X-ray emission spectrometry attached to a scanning electron microscope. Results:,Amphotericin B in a vial induced particle contamination during the reconstitution process, and the contamination was especially marked by shaking vigorously after injecting water into the vial. From the X-ray analysis, it appeared that the increased number of particles was derived from the amphotericin B,deoxycholate complex containing substances such as silicone released from the vial components. Amphotericin B fluid made with intravenous fluids after reconstitution also contained particles over the acceptable limits according to the Japanese or US pharmacopoeia. Conclusion:,These findings suggest that reconstituted solutions should be filtered with membrane filters and diluted fluids with in-line filters. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||