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Levels
Kinds of Levels Terms modified by Levels Selected AbstractsTHE OPTIMAL PUBLIC EXPENDITURE FINANCING POLICY: DOES THE LEVEL OF ECONOMIC DEVELOPMENT MATTER?ECONOMIC INQUIRY, Issue 3 2007NILOY BOSE This paper explores how the optimal mode of public finance depends on the level of economic development. The theoretical analysis suggests that in the presence of capital market imperfection and liquidity shocks, the detrimental effect of inflation on growth is stronger (weaker) at lower (higher) levels of economic development. Consequently, income taxation (seigniorage) is a relatively less distortionary way of financing public expenditure for low-income (high-income) countries. We provide empirical support for our model's predictions using a panel of 21 Organization for Economic Cooperation and Development countries and 40 developing countries observed over the period 1972,1999. (JEL E44, E6, H6, O42) [source] IS LEVEL OF INTEREST AMONG CANNABIS USERS IN SELF-HELP MATERIALS AND OTHER SERVICES AIMED AT REDUCING PROBLEM USE?ADDICTION, Issue 4 2005JOHN CUNNINGHAM No abstract is available for this article. [source] SEMOLINA AND HYDRATION LEVEL DURING EXTRUSION AFFECT QUALITY OF FRESH PASTA CONTAINING FLAXSEED FLOURJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2008SHALINI SINHA ABSTRACT Flaxseed (Linum usitatissimum L.) is an emerging food ingredient because of its several health benefits. Research was conducted to determine the effects of semolina, hydration level during extrusion and flaxseed flour concentration on the physical and cooking characteristics of freshly extruded pasta. The appearance of fresh pasta reflected the appearance of the ingredients. Fresh pasta became darker and redder as flaxseed flour concentration increased. Flaxseed flour did not affect cooking loss or water absorption during cooking of fresh pasta. However, flaxseed flour reduced the cooked firmness of fresh pasta by decreasing the dough strength. The cooked firmness of fresh pasta containing flaxseed flour was improved by using a semolina that makes a strong dough rather than a weak dough, and by extruding at a low (29%) compared to high (31%) hydration level. PRACTICAL APPLICATIONS Research results reported in this article would be useful in the development of a processing protocol for fresh pasta containing flaxseed flour and possibly other nontraditional ingredients. The results provide support for the need to use a strong dough-forming semolina and to extrude the semolina,flaxseed flour mixture at a low hydration level (29%) in order to produce a fresh pasta that has desirable cooking/cooked properties. [source] PHYLOGENETIC ANALYSIS OF PSEUDOCHLORODESMIS STRAINS REVEALS CRYPTIC DIVERSITY ABOVE THE FAMILY LEVEL IN THE SIPHONOUS GREEN ALGAE (BRYOPSIDALES, CHLOROPHYTA),JOURNAL OF PHYCOLOGY, Issue 3 2009Heroen Verbruggen The genus Pseudochlorodesmis (Bryopsidales) is composed of diminutive siphons of extreme morphological simplicity. The discovery of Pseudochlorodesmis -like juveniles in more complex Bryopsidales (e.g., the Halimeda microthallus stage) jeopardized the recognition of this genus. Confronted with this uncertainty, taxonomists transferred many simple siphons into a new genus, Siphonogramen. In this study, we used a multimarker approach to clarify the phylogenetic and taxonomic affinities of the Pseudochlorodesmis-Siphonogramen (PS) complex within the more morphologically complex bryopsidalean taxa. Our analyses reveal a new layer of diversity largely distinct from the lineages containing the structurally complex genera. The PS complex shows profound cryptic diversity exceeding the family level. We discuss a potential link between thallus complexity and the prevalence and profundity of cryptic diversity. For taxonomic simplicity and as a first step toward clarifying the taxonomy of these simple siphons, we propose to maintain Pseudochlorodesmis as a form genus and subsume Siphonogramen and Botryodesmis therein. [source] WHAT FEATURES DRIVE RATED BURGER CRAVEABILITY AT THE CONCEPT LEVEL?JOURNAL OF SENSORY STUDIES, Issue 1 2004JACQUELINE BECKLEY ABSTRACT This paper deals with the analysis of drivers for self-defined craveability assessed in an Internet-based, conjoint analysis task. The stimuli comprised 36 descriptions of restaurant hamburgers, including product features, benefits, restaurant names, and emotional reactions that might ensue after eating the hamburger. Elements were combined into concepts by experimental design, and the resulting concepts evaluated by 145 respondents, on the attribute of craveability. Models relating the presence/absence of concept elements to ratings revealed that statements about the hamburger itself were the most powerful, but that no single element was highest across all the respondents. Segmentation of the 145 individuals by the pattern of their individual utilities revealed four key segments. These are Elaborates who may be sensory-oriented and respond strongly to product descriptions; Classics who like the notion of a grilled hamburger; Imaginers who respond to restaurant name and advertising copy; and Emotionals who respond to statements about food to descriptions how the eater feels after consumption. [source] SUCCESSFUL AND UNSUCCESSFUL PARTICIPATORY ARRANGEMENTS: WHY IS THERE A PARTICIPATORY MOVEMENT AT THE LOCAL LEVEL?JOURNAL OF URBAN AFFAIRS, Issue 3 2010LAURENCE BHERER ABSTRACT:,The objective of this article is to explore some of the reasons for the growing number of participatory arrangements at the local level. An approach in terms of governance allows us to examine the underlying patterns of logic that induce public authorities to develop new policy tools such as participatory arrangements. Our study focuses on a medium-sized French city, Bordeaux, where eight types of relatively weak participatory arrangements have been implemented since 1995. The article shows that the French government and European Union have fostered this type of arrangement through a complex series of public programs and policies with the aim of rebuilding their political legitimacy by encouraging participation at the municipal level. This approach is relevant to understanding the origin of the reforms affecting local governments over the past decade. [source] THE FISCAL THEORY OF THE PRICE LEVEL: A CRITIQUE*THE ECONOMIC JOURNAL, Issue 481 2002Willem H. Buiter This paper argues that the `fiscal theory of the price level' (FTPL) has feet of clay. The source of the problem is a fundamental economic misspecification. The FTPL confuses two key building blocks of a model of a market economy: budget constraints, which must be satisfied identically, and market clearing or equilibrium conditions. The FTPL asssumes that the government's intertemporal budget constraint needs to be satisfied only in equilibrium. This economic misspecification has far-reaching implications for the mathematical properties of the equilibria supported by models that impose the structure of the FTPL. It produces a rash of contradictions and anomalies. [source] DOES THE MAGNITUDE OF THE EFFECT OF INFLATION UNCERTAINTY ON OUTPUT GROWTH DEPEND ON THE LEVEL OF INFLATION?THE MANCHESTER SCHOOL, Issue 2 2010KUANG-LIANG CHANG A bivariate Markov regime switching model is employed to verify whether the relationship between inflation and inflation uncertainty, or the negative effects of inflation and inflation uncertainty on output growth, vary with the level of inflation. Inflation and inflation uncertainty are positively correlated in the high-inflation regime. In contrast, in the low-inflation regime, the direct effect of inflation on output growth is insignificant, but the indirect negative effect on growth via inflation uncertainty is highly significant. The negative influence in a high-inflation regime is 2.664 times greater than that in a low-inflation regime. [source] THE EFFECT OF THE COLLECTIVE BARGAINING LEVEL ON THE GENDER WAGE GAP: EVIDENCE FROM SPAIN,THE MANCHESTER SCHOOL, Issue 3 2008FLORENTINO FELGUEROSO Several studies have found a negative relationship between the level of collective bargaining centralization and the degree of wage inequality. So, more centralized bargaining seems to lead to lower wage gaps. On the other hand, there is evidence that the gender wage gap increases as we move upwards along the wage distribution, illustrating the glass ceiling hypothesis. In this paper we study how the wage gap changes throughout the distribution of wages, as a function of the level of collective bargaining by which workers are covered, using data from the Spanish Wage Structure Survey of 2002. [source] PHYSICALISM, SUPERVENIENCE AND THE FUNDAMENTAL LEVELTHE PHILOSOPHICAL QUARTERLY, Issue 234 2009Robin Brown We provide a formulation of physicalism, and show that this is to be favoured over alternative formulations. Much of the literature on physicalism assumes without argument that there is a fundamental level to reality, and we show that a consideration of the levels problem and its implications for physicalism tells in favour of the form of physicalism proposed here. Its key elements are, first, that the empirical and substantive part of physicalism amounts to a prediction that physics will not posit new entities solely for the purpose of accounting for mental phenomena, nor new entities with essentially mental characteristics such as propositional attitudes or intentions; secondly, that physicalism can safely make do with no more than a weak global formulation of supervenience. [source] THE INFLUENCE OF VOLUNTEERS, DONATIONS AND PUBLIC SUBSIDIES ON THE WAGE LEVEL OF NONPROFIT WORKERS: EVIDENCE FROM AUSTRIAN MATCHED DATAANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 1 2010Astrid Haider ABSTRACT,:,In this article we add to the literature analyzing wages in the nonprofit sector by estimating a wage function based on employer-employee matched data for Austria. We concentrate on the influence of voluntary contributions on the wage level of paid workers. By using a quantile regression approach we find that the existence of volunteers reduces the wages of paid employees in nonprofit organizations. The number of volunteers does not have an influence on the wage level. Donations have a small but positive effect for higher income groups only. Public subsidies increase wages of all paid workers in a nonprofit organization. [source] SURGEON GENERAL: NO SAFE LEVEL FOR SECONDHAND SMOKECA: A CANCER JOURNAL FOR CLINICIANS, Issue 6 2006Article first published online: 31 DEC 200 No abstract is available for this article. [source] NANOMOLAR LEVEL OF OUABAIN INCREASES INTRACELLULAR CALCIUM TO PRODUCE NITRIC OXIDE IN RAT AORTIC ENDOTHELIAL CELLSCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 5-6 2004Xian Hui Dong Summary 1.,Changes in [Ca2+]i across the cell membrane and/or the sarcoplasmic reticulum regulate endothelial nitric oxide (NO) synthase activity. 2.,In the present study, we investigated the effect of ouabain, a specific inhibitor of Na+/K+ -ATPase, on NO release and [Ca2+]i movements in cultured rat aortic endothelial cells (RAEC) by monitoring NO production continuously using an NO-specific real-time sensor and by measuring the change in [Ca2+]i using a fluorescence microscopic imaging technique with high-speed wavelength switching. The t˝ (half-time of the decline of [Ca2+]i to basal levels after stimulation with 10 µmol/L bradykinin) was used as an index of [Ca2+]i extrusion. 3.,A very low concentration of ouabain (10 nmol/L) did not increase the peak of NO production, but decreased the decay of NO release and, accordingly, increased integral NO production by the maximal dose,response concentration induced by bradykinin. The same dose of ouabain affected [Ca2+]i movements across the cell membrane and/or sarcoplasmic reticulum induced by bradykinin with a time-course similar to that of NO release. Moreover, the t˝ was significantly increased. 4.,Pretreatment of RAEC with Na+ -free solution, an inhibitor of the Na+/Ca2+ exchanger, and nickel chloride hexahydrate prevented the effects induced by bradykinin and ouabain. 5.,These observations using real-time recording indicate that a small amount of ouabain contributes to the bradykinin-stimulated increase of NO production through inhibition of plasma membrane Na+/K+ -ATPase activity and an increase in intracellular Na+ concentrations. The membrane was then depolarized, leading to a decline in the bradykinin-stimulated increase in [Ca2+]i by forward mode Na+/Ca2+ exchange to prolong the Ca2+ signal time. 6.,From these results, we suggest that nanomolar levels of ouabain modulate [Ca2+]i movements and NO production in RAEC. [source] RESTING METABOLIC RATE AND POST-PRANDIAL THERMOGENESIS BY LEVEL OF AEROBIC POWER IN OLDER ATHLETESCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 4 2004Alessio Sullo SUMMARY 1.,The aim of the present study was to evaluate the resting metabolic rate (RMR) and thermogenic effect of a meal (TEM) in older athletes. 2.,Eighteen older male volunteers were divided into three groups according to their aerobic power related to fat-free mass (FFM) as follows: (i) group I, high aerobic power (Vo2max > 70 mL/kg FFM per min); (ii) group II, moderate aerobic power (Vo2max = 55,70 mL/kg FFM per min); and (iii) group III, low aerobic power (Vo2max < 55 mL/kg FFM per min). 3.,The RMR values, covariated for FFM using analysis of covariance (ancova), were higher in group I (mean (±SEM) 1.09 ± 0.04 kcal/min) than in groups II and III (0.99 ± 0.05 and 0.91 ± 0.03 kcal/min, respectively). Group I had a tendency for higher mean TEM values compared with the other groups, but the differences were not statistically significant for absolute or percentage values. 4.,Master endurance athletes with high aerobic power exhibit a higher RMR than master endurance athletes of similar age and body composition but with lower aerobic power. [source] THE SIXTIES: THE CALM AGAINST THE STORM, OR, LEVELS OF CONCERNEDUCATIONAL THEORY, Issue 3 2000Maxine Greene First page of article [source] COMPARATIVE GENOMIC AND POPULATION GENETIC ANALYSES INDICATE HIGHLY POROUS GENOMES AND HIGH LEVELS OF GENE FLOW BETWEEN DIVERGENT HELIANTHUS SPECIESEVOLUTION, Issue 8 2009Nolan C. Kane While speciation can be found in the presence of gene flow, it is not clear what impact this gene flow has on genome- and range-wide patterns of differentiation. Here we examine gene flow across the entire range of the common sunflower, H. annuus, its historically allopatric sister species H. argophyllus and a more distantly related, sympatric relative H. petiolaris. Analysis of genotypes at 26 microsatellite loci in 1015 individuals from across the range of the three species showed substantial introgression between geographically proximal populations of H. annuus and H. petiolaris, limited introgression between H. annuus and H. argophyllus, and essentially no gene flow between the allopatric pair, H. argophyllus and H. petiolaris. Analysis of sequence divergence levels among the three species in 1420 orthologs identified from EST databases identified a subset of loci showing extremely low divergence between H. annuus and H. petiolaris and extremely high divergence between the sister species H. annuus and H. argophyllus, consistent with introgression between H. annuus and H. petiolaris at these loci. Thus, at many loci, the allopatric sister species are more genetically divergent than the more distantly related sympatric species, which have exchanged genes across much of the genome while remaining morphologically and ecologically distinct. [source] BIOTIC INTERACTIONS AND MACROEVOLUTION: EXTENSIONS AND MISMATCHES ACROSS SCALES AND LEVELSEVOLUTION, Issue 4 2008David Jablonski Clade dynamics in the fossil record broadly fit expectations from the operation of competition, predation, and mutualism, but data from both modern and ancient systems suggest mismatches across scales and levels. Indirect effects, as when antagonistic or mutualistic interactions restrict geographic range and thereby elevate extinction risk, are probably widespread and may flow in both directions, as when species- or organismic-level factors increase extinction risk or speciation probabilities. Apparent contradictions across scales and levels have been neglected, including (1) the individualistic geographic shifts of species on centennial and millennial timescales versus evidence for fine-tuned coevolutionary relationships; (2) the extensive and dynamic networks of interactions faced by most species versus the evolution of costly enemy-specific defenses and finely attuned mutualisms; and (3) the macroevolutionary lags often seen between the origin and the diversification of a clade or an evolutionary novelty versus the rapid microevolution of advantageous phenotypes and the invasibility of most communities. Resolution of these and other cross-level tensions presumably hinges on how organismic interactions impinge on genetic population structures, geographic ranges, and the persistence of incipient species, but generalizations are not yet possible. Paleontological and neontological data are both incomplete and so the most powerful response to these problems will require novel integrative approaches. Promising research areas include more realistic approaches to modeling and empirical analysis of large-scale diversity dynamics of ostensibly competing clades; spatial and phylogenetic dissections of clades involved in escalatory dynamics (where prey respond evolutionarily to a broad and shifting array of enemies); analyses of the short- versus long-term consequences of mutualistic symbioses; and fuller use of abundant natural experiments on the evolutionary impacts of ecosystem engineers. [source] TIME TO THE MOST RECENT COMMON ANCESTOR AND DIVERGENCE TIMES OF POPULATIONS OF COMMON CHAFFINCHES (FRINGILLA COELEBS) IN EUROPE AND NORTH AFRICA: INSIGHTS INTO PLEISTOCENE REFUGIA AND CURRENT LEVELS OF MIGRATIONEVOLUTION, Issue 1 2002Cortland K. Griswold Abstract We analyzed sequences from a 275-bp hypervariable region in the 5, end of the mitochondrial DNA control region in 190 common chaffinches (Fringilla coelebs) from 19 populations in Europe and North Africa, including new samples from Greece and Morocco. Coalescent techniques were applied to estimate the time to the most recent common ancestor (TMRCA) and divergence times of these populations. The first objective of this study was to infer the locations of refugia where chaffinches survived the last glacial episode, and this was achieved by estimating the TMRCA of populations in regions surrounding the Mediterranean that were unglaciated in the late Pleistocene. Although extant populations in Iberia, Corsica, Greece, and North Africa harbor haplotypes that are basal in a phylogenetic tree, this information alone cannot be used to infer that these localities served as refugia, because it is impossible to infer the ages of populations and their divergence times without also considering the population genetic processes of mutation, migration, and drift. Provided we assume the TMRCAs of populations are a reasonable estimate of a population's age, coalescent-based methods place resident populations in Iberia, Corsica, Greece, and North Africa during the time of the last glacial maximum, suggesting these regions served as refugia for the common chaffinch. The second objective was to determine when populations began diverging from each other and to use this as a baseline to estimate current levels of gene flow. Divergence time estimates suggest that European populations began diverging about 60,000 years before present. The relatively recent divergence of populations in North Africa, Italy, and Iberia may explain why classic migration estimates based on equilibrium assumptions are high for these populations. We compare these estimates with nonequilibrium-based estimates and show that the nonequilibrium estimates are consistently lower than the equilibrium estimates. [source] CIRCULATING SEX HORMONE LEVELS AND AORTIC STIFFNESS IN MENJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2007Hamid Reza Nakhai Pour MD No abstract is available for this article. [source] PLASMA LEVELS OF INFLAMMATORY C-REACTIVE PROTEIN AND INTERLEUKIN-6 PREDICT OUTCOME IN ELDERLY PATIENTS WITH STROKEJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 9 2004Antonello Silvestri MD No abstract is available for this article. [source] EFFECT OF INSOLUBLE PARTICLES UPON SOLID INCLUSION LEVELS IN ICE FORMED ON A SUBCOOLED STAINLESS STEEL SURFACEJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2000PING CHEN ABSTRACT This study employed an insoluble solid particle, i.e. a potato starch used as an example, to investigate the impact of the concentration of such particles suspended in water (with solid loading of 5, 10, 20 and 30 wt%) upon the solid inclusion levels in ice layers formed on a sub-cooled smooth stainless steel plate surface. The effects of ice growth rate, bulk concentration and suspension velocity on insoluble solid inclusion, i.e. potato starch mass fraction, in ice layer were studied. The experiments, where potato starch is added into aqueous sucrose solutions or the reverse where sucrose is added into starch suspension, were also carried out to investigated effect of the starch particles on sucrose inclusion in ice and effect of solute (sucrose) on starch particle inclusion in ice. It has been found that solid inclusion in ice increases with increasing bulk concentration and average ice growth rate, at constant solution and coolant velocities, and increasing suspension velocity can help pure ice formation. The average distribution coefficient of sucrose in ice layer formed from sucrose solution does not appear to be affected by the addition of potato starch. However, the average distribution coefficient of potato starch in ice layer formed from suspension is influenced by sucrose concentration quite significantly. [source] RELATIONSHIPS of PHYSICAL PROPERTIES of FAT-SUBSTITUTES, COOKING METHODS and FAT LEVELS WITH QUALITY of GROUND BEEF PATTIESJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2000J. JU Ground beef patties containing 2 fat levels (5%, 10%), and 3 fat-substitutes (LeanBind, Rice* Complete 3, and Sta-Slim 171) were processed using 3 cooking methods (microwave, roasting, and pan-frying). Correlation analyses between patty quality and the physical properties of the fat-substitutes, as well as the composition of both raw and cooked patties were conducted. Regression models of patty quality parameters as functions of the physical properties of the fat-substitutes, and as the function of the patty composition were developed. This work demonstrated that the fat-substitutes can be evaluated based on regression models relating patty quality to the physical properties of the fat-substitutes. [source] FUNGI AND PATULIN IN APPLES AND THE ROLE OF PROCESSING ON PATULIN LEVELS IN JUICES: A STUDY ON NATURALLY CONTAMINATED APPLESJOURNAL OF FOOD SAFETY, Issue 2 2010JULIANE ELISA WELKE ABSTRACT The purpose of this study was to determine the predominant fungal species, including toxigenic strains, patulin levels in apples used for juice production and in produced juices. The possibility of use of apple highly contaminated with patulin to produce juice with lower patulin levels than the limit permitted by Codex Alimentarius was also checked. Sixteen lots of apples and juices were analyzed. The most prevalent fungal population was Penicillium spp. (93%) followed by the Aspergillus spp. (3.5%) and the Rhizopus spp. (3.5%). The mycoflora of apples was composed mainly of species that produce patulin. P. expansum was identified as the most frequently isolated species (66%). Species able to produce patulin were P. expansum and P. griseofulvum. Patulin levels in apples from cold storage ranged from 254.6 to 653.4 µg/kg. Apple juice processing caused average reduction of 95% in patulin levels. Patulin levels ranged from 14.3 to 46.7 µg/L in apple juices. In all samples were found patulin levels lower than the limit of 50 µg/L considered acceptable by the Codex Alimentarius Commission. PRACTICAL APPLICATIONS This study was performed to define the mycoflora of apples and patulin levels in apples that were used for juice production. This approach is useful to evaluate the quality of apples and the effect of processing on patulin to determine if the toxin level can be managed through postharvest procedures. Besides, information about patulin levels in juices is important to contribute for establishing national regulation. [source] VIRULENCE LEVELS OF BIOFILM-GROWN LISTERIA MONOCYTOGENES LO28 ARE LOWER THAN THOSE OF PLANKTONIC CELLS IN AN ORAL INOCULATION TEST ON MICEJOURNAL OF FOOD SAFETY, Issue 1 2007ETIENNE ZUNDEL ABSTRACT The aim of this study was to produce Listeria monocytogenes biofilms suitable for virulence assays and to determine whether the released bacteria had the same virulence potential as their planktonic counterparts. Biofilms of Listeria monocytogenes LO28 strain, with or without Sphingomonas paucimobilis CCL10 strain, containing up to 7 log10 cfu/cm2 were produced in polypropylene syringes. The virulence of strain LO28 was analyzed in mice after intravenous, subcutaneous and oral inoculation. Its virulence level in binary cultures was not significantly different from that of monocultures. L. monocytogenes LO28 virulence in biofilms was lower than that of their planktonic counterparts after oral inoculation. Our results suggest that biofilms pose no greater health risk to the consumer than planktonic bacteria. [source] INITIAL LEVELS OF DIFFERENTIATION AND REDUCTION IN PSYCHOLOGICAL SYMPTOMS FOR CLIENTS IN MARRIAGE AND FAMILY THERAPYJOURNAL OF MARITAL AND FAMILY THERAPY, Issue 1 2005Suzanne Bartle-Haring Using Bowen Family Systems Theory as a theoretical underpinning, in this study, we investigated the hypothesis that clients with higher levels of differentiation would improve more quickly in therapy than clients with lower levels of differentiation. Hierarchical Linear Modeling was used to analyze the data over nine sessions of therapy in a sample from an on-campus training clinic. The results suggest that there was variation in the initial levels of psychological symptoms and that differentiation was a significant predictor of this variance. The results also suggest that although psychological symptoms decreased over the nine sessions of therapy, there was very little variance in this change. These results are discussed in relation to Bowen Theory. The difficulties of doing this type of research and the lessons learned from this project are also discussed. [source] ESTABLISHMENT OF MINIMAL AND MAXIMAL TRANSCRIPT LEVELS FOR NITRATE TRANSPORTER GENES FOR DETECTING NITROGEN DEFICIENCY IN THE MARINE PHYTOPLANKTON ISOCHRYSIS GALBANA (PRYMNESIOPHYCEAE) AND THALASSIOSIRA PSEUDONANA (BACILLARIOPHYCEAE),JOURNAL OF PHYCOLOGY, Issue 4 2009Lee-Kuo Kang Nitrate transporter genes (Nrt2) encode high-affinity nitrate transporters in marine phytoplankton, and their transcript levels are potential markers of nitrogen deficiency in eukaryotic phytoplankton. For the proper interpretation of measured Nrt2 transcript abundances, a relative expression assay was proposed and tested in Isochrysis galbana Parke (Prymnesiophyceae) and Thalassiosira pseudonana (Hust.) Hasle et Heimdal (Bacillariophyceae). The minimal transcript levels of Nrt2 genes were achieved by the addition of 100 ,M ammonium, which led to a rapid decline in Nrt2 transcripts in 10,30 min. Experiments using a concentration series revealed that the effective dosage of ammonium to create a minimal transcript level of ,1 ,mol · mol,1 18S rRNA was ,25 ,M in both species. On the other hand, the addition of l -methionine sulfoximine (MSX), an inhibitor of glutamine synthetase, enhanced the Nrt2 transcript level in I. galbana but did not affect that in T. pseudonana. Nitrogen deprivation was used as an alternative means to create maximal Nrt2 transcript levels. By transferring cells into N-free medium for 24 h, Nrt2 transcript levels increased to ,90 ,mol · mol,1 18S rRNA in I. galbana, and to ,800 ,mol · mol,1 18S rRNA in T. pseudonana. The degree of nitrogen deficiency thus can be determined by comparing original Nrt2 transcript levels with the minimal and maximal levels. [source] DIEL VARIATIONS IN OPTICAL PROPERTIES OF IMANTONIA ROTUNDA (HAPTOPHYCEAE) AND THALASSIOSIRA PSEUDONANA (BACILLARIOPHYCEAE) EXPOSED TO DIFFERENT IRRADIANCE LEVELS,JOURNAL OF PHYCOLOGY, Issue 3 2008Sébastien Mas Diel variations of cellular optical properties were examined for cultures of the haptophyte Imantonia rotunda N. Reynolds and the diatom Thalassiosira pseudonana (Hust.) Hasle et Heimdal grown under a 14:10 light:dark (L:D) cycle and transferred from 100 ,mol photons · m,2 · s,1 to higher irradiances of 250 and 500 ,mol photons · m,2 · s,1. Cell volume and abundance, phytoplankton absorption coefficients, flow-cytometric light scattering and chl fluorescence, and pigment composition were measured every 2 h over a 24 h period. Results showed that cell division was more synchronous for I. rotunda than for T. pseudonana. Several variables exhibited diel variability with an amplitude >100%, notably mean cell volume for the haptophyte and photoprotective carotenoids for both species, while optical properties such as flow-cytometric scattering and chl a,specific phytoplankton absorption generally showed <50% diel variability. Increased irradiance induced changes in pigments (both species) and mean cell volume (for the diatom) and amplified diel variability for most variables. This increase in amplitude is larger for pigments (factor of 2 or more, notably for cellular photoprotective carotenoid content in I. rotunda and for photosynthetic pigments in T. pseudonana) than for optical properties (a factor of 1.5 for chl a,specific absorption, at 440 nm, in I. rotunda and a factor of 2 for the absorption cross-section and the chl a,specific scattering in T. pseudonana). Consequently, diel changes in optical properties and pigmentation associated with the L:D cycle and amplified by concurrent changes in irradiance likely contribute significantly to the variability in optical properties observed in biooptical field studies. [source] WINTER PHYTOPLANKTON BLOOMS UNDER ICE ASSOCIATED WITH ELEVATED OXYGEN LEVELS,JOURNAL OF PHYCOLOGY, Issue 6 2002Karen A. Phillips Many shallow lakes in north temperate zones experience reduced dissolved oxygen concentration under ice. However, some shallow lakes display supersaturated dissolved oxygen concentrations (>20 mg·L,1) in late winter under conditions of maximum ice thickness. During the winters of 1996, 1997, and 1999, we collected phytoplankton samples from Arrowwood Lake near Pingree, North Dakota to determine whether a specific alga was involved in dissolved oxygen supersaturation in this lake. Although dissolved oxygen supersaturation was not observed during this period, we did observe an increase in dissolved oxygen concentration that was associated with a phytoplankton bloom during late February and early March in both 1996 and 1997. In 1996, the bloom was composed of the dinoflagellate, Peridinium aciculiferum (Lemm.) Lemm. and several species of cryptomonads. A similar bloom of P. aciculiferum was followed by a bloom of several species of euglenoids in 1997. In contrast, P. aciculiferum was only a minor component of the winter phytoplankton, dissolved oxygen concentrations remained low, and no bloom event was observed in 1999. Statistical analyses indicated a significant relationship (rs = 0.57, P = 0.019) between dissolved oxygen levels and the density of the dinoflagellate, P. aciculiferum, but no significant relationship between dissolved oxygen levels and densities of other phytoplankton. These results suggest that the elevated levels of dissolved oxygen are associated with the dinoflagellate, P. aciculiferum. This bloom was most likely the result of an excystment event rather than a general growth response. [source] ORAL PHOSPHATE BINDERS FOR THE MANAGEMENT OF SERUM PHOSPHATE LEVELS IN DIALYSIS PATIENTSJOURNAL OF RENAL CARE, Issue 2009Ismail Mohammed MBBS, MRCP SUMMARY Hyperphosphataemia is an inevitable consequence of end stage chronic kidney disease and is present in the majority of dialysis patients. Hyperphosphataemia is statistically associated with increased cardiovascular mortality among dialysis patients. Dietary restriction of phosphate and current dialysis modalities are not sufficiently effective to maintain serum phosphate levels within the recommended range so that the majority of dialysis patients require oral phosphate binders. However, benefits of achieving the recommended range have yet to be demonstrated prospectively. Unfortunately, conventional phosphate binders are not reliably effective and are associated with a range of limitations and side effects. Aluminium containing agents are highly efficient but no longer widely used because of well-established and proven toxicity. Calcium-based salts are inexpensive, effective and most widely used but there is now concern about their association with hypercalcaemia and vascular calcification. Sevelamer hydrochloride and lanthanum carbonate are non-aluminium, calcium-free phosphate binders. They are effective and reasonably well tolerated, but still do not control phosphate levels in all patients. Patient education programmes have been shown to be a useful and effective method of improving achievement of serum phosphate targets. [source] I. LEVELS OF HUMAN BODY KNOWLEDGE IN DEVELOPMENTMONOGRAPHS OF THE SOCIETY FOR RESEARCH IN CHILD DEVELOPMENT, Issue 2 2004Article first published online: 12 AUG 200 First page of article [source] | ||||||||||||||||||||||||||||||||||