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Selected AbstractsThe theory of cosy NMR experiments revisited: Application to an AX spin system of quadrupolar nucleiCONCEPTS IN MAGNETIC RESONANCE, Issue 3 2010P. Kempgens Abstract The two-dimensional nuclear magnetic resonance correlation spectroscopy (2D NMR COSY) spectrum of an AX spin system of spin-1 has been calculated by numerical density matrix calculations. The mathematical expressions found are valid for an AX spin system of any spins. These expressions should be used to calculate the 2D NMR COSY spectrum of an AX spin system of high spin nuclei as their use will significantly simplify the calculations. More precisely, one needs to calculate only one set of coefficients despite the need of two steps in the phase cycling to achieve phase modulation during t1. © 2010 Wiley Periodicals, Inc. Concepts Magn Reson Part A 36A: 170,177, 2010. [source] Conflict resolution in a non-Western context: Conversations with Indonesian scholars and practitionersCONFLICT RESOLUTION QUARTERLY, Issue 4 2006Brett R. Noel This paper describes two sets of U.S. Department of State funded workshops conducted in 2003. The purpose of one set of workshops was to introduce Indonesian educators and community leaders to Western-influenced conflict resolution education (CRE) while the other workshops sought to encourage participants to engage in conflict-focused research adapted to the culture and needs of Indonesia. [source] Fixing the Hole in the Bucket: Household Poverty Dynamics in the Peruvian AndesDEVELOPMENT AND CHANGE, Issue 5 2006Anirudh Krishna ABSTRACT Achieving the Millennium Development Goal of halving poverty will require simultaneous action on two separate fronts: helping poor people escape from poverty, and stemming the flow of people into poverty. This article examines forty Peruvian communities, and finds that descents into poverty have occurred alongside escapes in every one of them. Escape and descent are asymmetric in terms of reasons: while one set of reasons is responsible for escapes from poverty, another and different set of reasons is associated with descent. Making progress in poverty reduction will require measures to accelerate escapes whilst at the same time slowing down descents. The article looks at the different policies which will be required to serve these two separate purposes. [source] Blood Cultures Do Not Change Management in Hospitalized Patients with Community-acquired PneumoniaACADEMIC EMERGENCY MEDICINE, Issue 7 2006Prasanthi Ramanujam MD Objectives: To determine if blood cultures identify organisms that are not appropriately treated with initial empiric antibiotics in hospitalized patients with community-acquired pneumonia, and to calculate the costs of blood cultures and cost savings realized by changing to narrower-spectrum antibiotics based on the results. Methods: This was a retrospective observational study conducted in an urban academic emergency department (ED). Patients with an ED and final diagnosis of community-acquired pneumonia admitted between January 1, 2001, and August 30, 2003, were eligible when the results of at least one set of blood cultures obtained in the ED were available. Exclusion criteria included documented human immunodeficiency virus infection, immunosuppressive illness, chronic renal failure, chronic corticosteroid therapy, documented hospitalization within seven days before ED visit, transfer from another hospital, nursing home residency, and suspected aspiration pneumonia. The cost of blood cultures in all patients was calculated. The cost of the antibiotic regimens administered was compared with narrower-spectrum and less expensive alternatives based on the results. Results: A total of 480 patients were eligible, and 191 were excluded. Thirteen (4.5%) of the 289 enrolled patients had true bacteremia; the organisms isolated were sensitive to the empiric antibiotics initially administered in all 13 cases (100%; 95% confidence interval = 75% to 100%). Streptococcus pneumoniae and Haemophilus influenzae were isolated in 11 and two patients, respectively. The potential savings of changing the antibiotic regimens to narrower-spectrum alternatives was only 170. Conclusions: Appropriate empiric antibiotics were administered in all bacteremic patients. Antibiotic regimens were rarely changed based on blood culture results, and the potential savings from changes were minimal. [source] How children know the relevant properties for generalizing object namesDEVELOPMENTAL SCIENCE, Issue 2 2002Susan S. Jones Young children's novel word extensions indicate that their animal categories, like those of adults, are characterized by multiple similarities among instances; whereas their artifact categories, again like those of adults, are characterized more simply by commonalities among instances in shape. Three experiments shed light on the nature and development of a mechanism that enables children to organize novel lexical categories differently for different kinds of objects. Experiment 1 shows that, by adult judgments, animals and artifacts present different category organizations. Experiment 2 shows relations between both age and the number of nouns young children have acquired, and children's kind-specific generalizations of newly learned nouns. Experiment 3 is a training study in which even younger children show an ability to learn and then generalize highly abstract relations between different contextual cues and different category structures; and importantly, to learn more than one set of such relations at a time. Together, these three findings indicate one way in which children are able to rapidly and accurately form lexical categories that parallel those of adults in their language community. [source] Comparison of international and New Zealand guidelines for the care of pregnant women with diabetesDIABETIC MEDICINE, Issue 5 2006W. A. Cutchie Abstract Objective To compare international guidelines for the care of women with diabetes and pregnancy with reported current practice among New Zealand tertiary centres. Research design and methods A literature review of national and international guidelines for the care of women with diabetes in pregnancy was undertaken. Guideline activities were placed within nine facets of care, from preconception advice, through pregnancy from screening to follow-up. New Zealand tertiary centres guidelines were obtained and placed in the same framework. Results International guideline consensus was inconsistent across most facets of care. Those for the detection and diagnosis of gestational diabetes mellitus (GDM) were particularly discordant internationally, although intranational agreement has occurred. Conclusions International guidelines for the care of women with diabetes in pregnancy remain fragmented. The development of one set of guidelines based on the consensus of international best practice could overcome many of the misconceptions associated with diabetes in pregnancy. [source] Model updating using noisy response measurements without knowledge of the input spectrumEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 2 2005Ka-Veng Yuen Abstract A new probabilistic model identification methodology is proposed using measured response time histories only. The proposed approach requires that the number of independent measurements is larger than the number of independent excitations. Under this condition, no input measurements or any information regarding the stochastic model of the input is required. Specifically, the method does not require the response to be stationary and does not assume any knowledge of the parametric form of the spectral density of the input. Therefore, the method has very wide applicability. The proposed approach allows one to obtain not only the most probable values of the updated model parameters but also their associated uncertainties using only one set of response data. It is found that the updated probability distribution can be well approximated by a Gaussian distribution centered at the most probable values of the parameters. Examples are presented to illustrate the proposed method. Copyright © 2004 John Wiley & Sons, Ltd. [source] CONVERGENCE AND THE MULTIDIMENSIONAL NICHEEVOLUTION, Issue 2 2005Luke J. Harmon Abstract Convergent evolution has played an important role in the development of the ecological niche concept. We investigated patterns of convergent and divergent evolution of Caribbean Anolis lizards. These lizards diversified independently on each of the islands of the Greater Antilles, producing the same set of habitat specialists on each island. Using a phylogenetic comparative framework, we examined patterns of morphological convergence in five functionally distinct sets of morphological characters: body size, body shape, head shape, lamella number, and sexual size dimorphism. We find evidence for convergence among members of the habitat specialist types for each of these five datasets. Furthermore, the patterns of convergence differ among at least four of the five datasets; habitat specialists that are similar for one set of characters are often greatly different for another. This suggests that the habitat specialist niches into which these anoles have evolved are multidimensional, involving several distinct and independent aspects of morphology. [source] Assessing the influence of scanner background noise on auditory processing.HUMAN BRAIN MAPPING, Issue 8 2007Abstract We compared two experimental designs aimed at minimizing the influence of scanner background noise (SBN) on functional MRI (fMRI) of auditory processes with one conventional fMRI design. Ten subjects listened to a series of four one-syllable words and had to decide whether two of the words were identical. This was contrasted with a no-stimulus control condition. All three experimental designs had a duration of ,17 min: 1) a behavior interleaved gradients (BIG; Eden et al. [1999] J Magn Reson Imaging 41:13,20) design (repetition time, TR, = 6 s), where stimuli were presented during the SBN-free periods between clustered volume acquisitions (CVA); 2) a sparse temporal sampling technique (STsamp; e.g., Gaab et al., [2003] Neuroimage 19:1417,1426) acquiring only one set of slices following each of the stimulations with a 16-s TR and jittered delay times between stimulus offset and image acquisition; and 3) an event-related design with continuous scanning (ERcont) using the stimulation design of STsamp but with a 2-s TR. The results demonstrated increased signal within Heschl's gyrus for the STsamp and BIG-CVA design in comparison to ERcont as well as differences in the overall functional anatomy among the designs. The possibility to obtain a time course of activation as well as the full recovery of the stimulus- and SBN-induced hemodynamic response function signal and lack of signal suppression from SBN during the STsamp design makes this technique a powerful approach for conducting auditory experiments using fMRI. Practical strengths and limitations of the three auditory acquisition paradigms are discussed. Hum Brain Mapp, 2006. © 2006 Wiley-Liss, Inc. [source] Timing and connectivity in the human somatosensory cortex from single trial mass electrical activityHUMAN BRAIN MAPPING, Issue 4 2002Andreas A. Ioannides Abstract Parallel-distributed processing is ubiquitous in the brain but often ignored by experimental designs and methods of analysis, which presuppose sequential and stereotypical brain activations. We introduce here a methodology that can effectively deal with sequential and distributed activity. Regional brain activations elicited by electrical median nerve stimulation are identified in tomographic estimates extracted from single trial magnetoencephalographic signals. Habituation is identified in both primary somatosensory cortex (SI) and secondary somatosensory cortex (SII), often interrupted by resurgence of strong activations. Pattern analysis is used to identify single trials with homogeneous regional brain activations. Common activity patterns with well-defined connectivity are identified within each homogeneous group of single trials across the subjects studied. On the contralateral side one encounters distinct sets of single trials following identical stimuli. We observe in one set of trials sequential activation from SI to SII and insula with onset of SII at 60 msec, whereas in the other set simultaneous early co-activations of the same two areas. Hum. Brain Mapping 15:231,246, 2002. © 2002 Wiley-Liss, Inc. [source] Examination of cytotoxicity and mutagenicity of AH26 and AH Plus sealersINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2003I. Mileti Abstract Aim ,To study in vitro the cytotoxic and mutagenic effects of AH26 and AH Plus. Methodology ,Cytotoxic effects on Chinese hamster V79 cells were determined by counting viable cells following incubation with eluations of AH26 and AH Plus. In one set of experiments, the materials were mixed, set for 1 h and then eluted with dimethyl sulphoxide (DMSO) for 1 h, 24 h and 7 days. In the other set, AH26 and AH Plus were mixed and set for 1 h, 24 h and 7 days in physiological saline then crushed and eluted in DMSO for 24 h. The cytotoxic effects of these eluates were evaluated. Three concentrations were chosen to examine the mutagenic effects of AH26 and AH Plus: 5.57, 16.7 and 55.7 ,g mL,1. The structural chromosomal aberration analysis and micronucleus test were performed on human lymphocytes according to standard procedures. Results ,Dose,response curves of cell survival were obtained. Both materials were shown to be cytotoxic in doses larger than 55.7 ,g mL,1, except for AH26, after 7 days setting time. AH Plus was also shown to be toxic in concentrations of 16.7 ,g mL,1, except after 7 days setting time. Neither AH26 nor AH Plus induced a significant increase of chromosomal aberrations or micronuclei induction at any setting time or concentration. Conclusion ,There was no mutagenicity found for AH26 and AH Plus on human lymphocytes in highly controlled conditions in vitro. [source] Kinship systems and language choice among academics in Shillong, Northeast IndiaINTERNATIONAL JOURNAL OF APPLIED LINGUISTICS, Issue 2 2001Anne Hvenekilde In Shillong, the capital of the northeastern Indian state of Meghalaya, Indo-Aryan languages from the plains meet the Tibeto-Burman and Austro-Asiatic minority languages of the hills, and the result is a degree of multilingualism that is high even by Indian standards. English is widely used by academic groups everywhere in India, but structured interviews with all 17 faculty members of two departments at North-Eastern Hill University in Shillong reveal special reasons why some parents now choose to use English with their children rather than their own mother tongue. Caste imposes fewer barriers in this part of India than elsewhere, and marriages across ethnic groups are common, but con ?icting kinship practices can bring complications. If a woman from a matrilineal group marries a man from a patrilineal group, both families will, according to their traditions, consider the children to belong to their kinship group. Using English with their children, rather than choosing the language of just one set of grand-parents, can be a way of avoiding potential con?ict. Thus, in addition to the use of English in higher education, increasing geographic mobility, and the general prestige of English, the con?icting demands of different kinship systems needs to be considered among the factors contributing to the spread of English at the cost of local languages in Northeast India. [source] Fine mapping and detection of the causative mutation underlying Quantitative Trait LociJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 5 2010E. Uleberg Summary The effect on power and precision of including the causative SNP amongst the investigated markers in Quantitative Trait Loci (QTL) mapping experiments was investigated. Three fine mapping methods were tested to see which was most efficient in finding the causative mutation: combined linkage and linkage disequilibrium mapping (LLD); association mapping (MARK); a combination of LLD and association mapping (LLDMARK). Two simulated data sets were analysed: in one set, the causative SNP was included amongst the markers, while in the other set the causative SNP was masked between markers. Including the causative SNP amongst the markers increased both precision and power in the analyses. For the LLD method the number of correctly positioned QTL increased from 17 for the analysis without the causative SNP to 77 for the analysis including the causative SNP. The likelihood of the data analysis increased from 3.4 to 13.3 likelihood units for the MARK method when the causative SNP was included. When the causative SNP was masked between the analysed markers, the LLD method was most efficient in detecting the correct QTL position, while the MARK method was most efficient when the causative SNP was included as a marker in the analysis. The LLDMARK method, combining association mapping and LLD, assumes a QTL as the null hypothesis (using LLD method) and tests whether the ,putative causative SNP' explains significantly more variance than a QTL in the region. Thus, if the putative causative SNP does not only give an Identical-By-Descent (IBD) signal, but also an Alike-In-State (AIS) signal, LLDMARK gives a positive likelihood ratio. LLDMARK detected less than half as many causative SNPs as the other methods, and also had a relatively high false discovery rate when the QTL effect was large. LLDMARK may however be more robust against spurious associations, because the regional IBD is largely corrected for by fitting a QTL effect in the null hypothesis model. [source] Diffusion and spillover of new technology: a heterogeneous-agent model for cassava in West AfricaAGRICULTURAL ECONOMICS, Issue 2 2006Michael E. Johnson Positive mathematical programming; Technology adoption; Technical change Abstract Understanding what determines the geographic spread of innovations can help guide the funding and implementation of research and extension programs. Our approach uses household survey data as model parameters, to simulate behavior across the entire surveyed population and avoid the aggregation bias associated with representative-farm models. Such a "heterogeneous agent" approach allows us to infer the distribution of a technology's impacts across one set of households, and predict the potential for spreading to another set that shares similar characteristics with respect to natural resource endowments and farming systems. We apply the technique to new cassava varieties in West Africa, finding a strongly poverty-alleviating impact, with substantial spillover potential from Nigeria to neighboring countries. [source] Counter-current gas-liquid wavy film flow between the vertical plates analyzed using the Navier-Stokes equationsAICHE JOURNAL, Issue 8 2010Yu. Ya. Abstract The article is devoted to a theoretical analysis of counter-current gas-liquid wavy film flow between vertical plates. We consider two-dimensional nonlinear waves on the interface over a wide variation of parameters. The main interest is to analyse the wave structure at the parameter values corresponding to the onset of flooding observed in experiments. We use the Navier-Stokes equations in their full statement to describe the liquid phase hydrodynamics. For the gas phase equations, we use two models: (1) the Navier-Stokes system and (2) the simplified Benjamin-Miles approach where the liquid phase is a small disturbance for the laminar or turbulent gas flow. With the superficial gas velocity increasing and starting from some value of the velocity, the waves demonstrate a rapid decreasing of both the minimal film thickness and the phase wave velocity. We obtain a region of the gas velocity where we have two solutions at one set of the problem parameters and where the flooding takes place. Both the phase wave velocity and the minimal film thickness are positive numbers at such values of the velocity. We calculate the flooding point dependences on the liquid Reynolds number for two different liquids. The wave regime corresponding to the flooding point demonstrates negative u- velocities in the neighbourhood of the interface near the film thickness maximum. At smaller values of the superficial gas velocity, the negative u- velocities take place in the neighbourhood of the film thickness minimum. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Human Rights Barriers for Displaced Persons in Southern SudanJOURNAL OF NURSING SCHOLARSHIP, Issue 3 2009Carol Pavlish PhD Abstract Purpose: This community-based research explores community perspectives on human rights barriers that women encounter in a postconflict setting of southern Sudan. Methods: An ethnographic design was used to guide data collection in five focus groups with community members and during in-depth interviews with nine key informants. A constant comparison method of data analysis was used. Atlas.ti data management software facilitated the inductive coding and sorting of data. Findings: Participants identified three formal and one set of informal community structures for human rights. Human rights barriers included shifting legal frameworks, doubt about human rights, weak government infrastructure, and poverty. Conclusions: The evolving government infrastructure cannot currently provide adequate human rights protection, especially for women. The nature of living in poverty without development opportunities includes human rights abuses. Good governance, protection, and human development opportunities were emphasized as priority human rights concerns. Human rights framework could serve as a powerful integrator of health and development work with community-based organizations. Clinical Relevance: Results help nurses understand the intersection between health and human rights as well as approaches to advancing rights in a culturally attuned manner. [source] Phase behavior and photo-responsive studies of photoactive liquid crystalline hyperbranched polyethers containing benzylidene moietyJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 11 2009V. Srinivasa Rao Abstract Two sets of hyperbranched polyether epoxies were synthesized to study the effect of substituent, rigidity, and nature of photoactive unit on the thermal and photoresponsive properties. Each set was comprised of one molecule with an acyclic moiety in the repeating unit, and two molecules with a cyclic moiety of varying rigidity (cycle size) in the repeating unit. Two substituents on aromatic rings in the repeating unit were present in one set, and other set was without a substituent. The mesogenic and photoresponsive properties were studied and correlated to the varied structural parameters. The effects of varied molecular structural parameters on phase behavior and photoresponsive properties were very prominent. Out of six monomeric diols, only four have exhibited liquid crystalline phase while the polymers corresponding to all monomeric diols revealed mesophase. The findings in photoresponsive properties were further supported by molecular modeling studies. The changes in refractive index, photoviscosity, and fluorescence intensity with irradiation time substantiated the spectral pattern observed in UV-Vis spectroscopy. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2774,2786, 2009 [source] High-throughput operation of sample-exchange robots with double tongs at the Photon Factory beamlinesJOURNAL OF SYNCHROTRON RADIATION, Issue 3 2008Masahiko Hiraki Sample-exchange robots that can exchange cryo-pins bearing protein crystals out of experimental hutches according to user instructions have been developed. The robots were designed based on the SAM (Stanford Synchrotron Research Laboratory automated mounting) system. In order to reduce the time required for the sample exchange, the single tongs of the SAM system were modified and a double-tongs system that can hold two cryo-pins at the same time was developed. Robots with double tongs can move to the goniometer head holding the next cryo-pin with one set of tongs, dismount the experimented cryo-pin with the other set, and then mount the next pin onto the goniometer head without leaving the diffractometer area. Two different types of tongs have been installed: single tongs at beamlines BL-5A and AR-NW12A, and a double-tongs system at beamline BL-17A of the Photon Factory. The same graphical user interface software for operation of the sample-exchange robots is used at all beamlines, however, so that users do not need to consider differences between the systems. In a trial, the robot with double tongs could exchange samples within 10,s. [source] The European NEAT Program: An Integrated Approach Using Acamprosate and Psychosocial Support for the Prevention of Relapse in Alcohol-Dependent Patients With a Statistical Modeling of Therapy Success PredictionALCOHOLISM, Issue 10 2002Isidore Pelc Background A multicenter, prospective study was conducted in five European countries to observe outcome in alcohol misusers treated for 24 weeks with acamprosate and various psychosocial support techniques, within the setting of standard patient care. Methods Patients diagnosed as alcohol dependent using DSM-III-R criteria were treated, for 24 weeks, with acamprosate and appropriate psychosocial support. Potential predictor variables were recorded at inclusion. Drinking behavior was monitored throughout; the proportion of cumulative abstinence days was the principal outcome measure. The influence of baseline clinical and demographic variables on outcome was assessed using multiple regression analysis. Adverse events were recorded systematically. Results A total of 1289 patients were recruited; 1230 took at least one dose of the drug and provided at least one set of follow-up data; 543 (42.1%)patients were observed for the full 24-week period. The overall proportion of cumulative abstinence days was 0.48. Multiple physical and psychiatric comorbidities and a history of drug addiction were negatively correlated with outcome, as were, to a lesser extent, multiple previous episodes of detoxification, unemployment, and living alone. Older age and stable employment were positively associated with outcome. The difference in the unadjusted proportion of cumulative abstinence days between countries was significant (p < 0.001) but less so when adjusted for the predictive factors identified in the multivariate model (p < 0.019). Overall, outcome was not influenced by the nature of the psychosocial support provided. Adverse events were generally mild, with gastrointestinal disorders, which occurred in 21.5% of patients, being the most frequent. Conclusions This open-label study confirms the efficacy and safety of acamprosate in the treatment of alcohol dependence in the setting of standard patient care. Treatment benefit was observed irrespective of the nature of the psychosocial support provided. Predictors of the response to treatment were identified; their heterogeneous distribution within the study population explained, at least in part, the differences in outcome between countries. [source] PRESENTISM: THROUGH THICK AND THINPACIFIC PHILOSOPHICAL QUARTERLY, Issue 3 2008H. SCOTT HESTEVOLD Without defending Presentism, I argue first that Presentists should be Time -Free Presentists , Presentists whose views do not imply that there exist irreducible times. Second, I argue that Presentists should accept Limited Thick Presentism, the view that ,the present' has some extension and is thereby neither durationlessly thin nor unlimitedly ,thick'. Third, before addressing several objections to Limited Time-Free Thick Presentism [LTFTP], I argue that defenders of LTFTP should accept that ,temporal becoming' involves an overlapping succession of present entities, not a ,skipping' from one set of present entities to the next discrete set. [source] Simulation of the percolation of water into rigid polyurethane foams at applied hydraulic pressuresPOLYMER ENGINEERING & SCIENCE, Issue 7 2006Pravakar Mondal The hydraulic resistance of polyurethane foams is studied by means of simulations of water penetration into model foams. The model foams of cubical shape are constructed by generating the centers of the cells randomly. The strength of the window separating two cells is assumed to be a function of the distance between the centers of the cells in one set of computations. In another set of computations the strengths of the windows are assigned randomly from a specified distribution. The foam is exposed to an elevated pressure at its boundaries and water penetrates into the foam by rupturing the windows with strengths lesser than the applied pressure. The variation of equilibrium volume fraction of the foam filled with water for increasing hydraulic pressures shows typical percolation behavior: there is a sharp increase in the volume filled beyond a threshold pressure. Simulations show that beyond a certain sample size there is no change in the percolation curve with sample size, and indicate that it is mainly the weaker windows that control the hydraulic resistance of the foam. The simulation results are compared with experimental data. POLYM. ENG. SCI. 46:970,983, 2006. © 2006 Society of Plastics Engineers [source] Causal Inference with Differential Measurement Error: Nonparametric Identification and Sensitivity AnalysisAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 2 2010Kosuke Imai Political scientists have long been concerned about the validity of survey measurements. Although many have studied classical measurement error in linear regression models where the error is assumed to arise completely at random, in a number of situations the error may be correlated with the outcome. We analyze the impact of differential measurement error on causal estimation. The proposed nonparametric identification analysis avoids arbitrary modeling decisions and formally characterizes the roles of different assumptions. We show the serious consequences of differential misclassification and offer a new sensitivity analysis that allows researchers to evaluate the robustness of their conclusions. Our methods are motivated by a field experiment on democratic deliberations, in which one set of estimates potentially suffers from differential misclassification. We show that an analysis ignoring differential measurement error may considerably overestimate the causal effects. This finding contrasts with the case of classical measurement error, which always yields attenuation bias. [source] Modélisation de la cinétique de biodégradation de phénol par granules aérobiesTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2008Claudia Calvario-Rivera Abstract Ce travail est consacré à la modélisation de la cinétique de biodégradation de phénol par granules aérobies. Ceux-ci ont été obtenus à partir de la culture à alimentation séquentielle d'un surnageant de boues activées sur une eau usée synthétique,; puis ils ont été acclimatés au phénol (100 mg/L). La biodégradation de différentes concentrations de phénol (40,1112 mg/L) a été étudiée en fioles agitées ensemencées avec des granules acclimatés. Un modèle de type Haldane a été sélectionné, qui permet de décrire de manière adéquate l'évolution de la concentration de phénol avec un seul jeu de paramètres. Ce modèle pourrait permettre de mieux comprendre la biodégradation de molécules toxiques telles que le phénol dans des réacteurs granulaires aérobies. This work describes a model of the biodegradation of phenol carried out by aerobic granules. These granules were obtained by culturing an activated sludge supernatant in a sequencing batch reactor fed with a synthetic waste water and subsequently, by acclimation to phenol (100 mg/L). The kinetics of phenol biodegradation by the aerobic granules was investigated over a wide range of initial phenol concentrations (40,1112 mg/L) in shake-flask cultures. A Haldane-type model was adjusted to the experimental results, which depicts successfully the phenol biodegradation profiles in the entire range of initial concentrations studied by using only one set of parameters. It is our view that the proposed model could contribute to the knowledge about the ability of aerobic granular systems to biodegrade toxic, inhibitory compounds such as phenol. [source] Feasibility of pacific white shrimp Litopenaeus vannamei culture in southern Brazil: effects of stocking density and a single or a double CROP management strategy in earthen pondsAQUACULTURE RESEARCH, Issue 2 2010Dariano Krummenauer Abstract Marine shrimp culture at southern Brazil is restricted to the warmer season (November to April). Therefore, farmers must consider culture strategies and competition with shrimp landings from artisanal fishery. The fishing season starts every 1 February; in order to obtain higher prices, farmers may consider shrimp culture in two crops, with a first harvest before the start of the fishing season, and a second harvest after the end of the landings. The present study evaluated the performance and feasibility of Litopenaeus vannamei reared at 10, 25 and 40 shrimp m,2 either in two short consecutive culture cycles or one longer cycle (LC). The experimental design consisted of two sets of nine pens installed in a 3.8 ha earthen pond. In one set of pens, shrimp were harvested after 75 days and pens were restocked for another 75-day-long rearing period. In the second set of pens, shrimp were cultured for 150 days. Shrimp survival and final weight ranged from 79% to 91% and 6.67 to 14.53 g respectively. Feasibility analysis pointed towards culture at higher densities (25 and 40 shrimp m,2) in a LC as productivity (2274,4227 kg ha,1) and shrimp final weight (13.05,13.21 g) resulted in higher profitability (US$7761,12 379). [source] Pancreatic fate of a 125I-labelled mouse monoclonal antibody directed against pancreatic B-cell surface ganglioside(s) in control and diabetic ratsCELL BIOCHEMISTRY AND FUNCTION, Issue 2 2001Laurence Ladri Abstract The possible use of a mouse monoclonal antibody directed against rat pancreatic B-cell surface ganglioside(s) and labelled with radioactive iodine for selective imaging of the endocrine pancreas by a non-invasive procedure was investigated by following its pancreatic fate in experiments conducted either in vitro by incubation of rat isolated pancreatic islets, acinar tissue and pancreatic pieces or in vivo after intravenous injection of the 125I-labelled antibodies ([125I],-G). Although the binding of [125I],-G per µg protein was about one order of magnitude higher in isolated islets than in acinar tissue, no significant difference was detected when comparing pancreatic pieces or isolated islets from control animals and rats rendered diabetic by one or two prior administrations of streptozotocin (STZ rats). Likewise, except in one set of experiments, no significant difference was found between control animals and STZ rats, when measuring the radioactive content of the pancreatic gland, relative to that of plasma, 1,4 days after the intravenous injection of [125I],-G. These findings indicate that under the present experimental conditions, the mouse monoclonal antibody labelled with radioactive iodine does not appear to be a promising tool for selective imaging of the endocrine pancreas, e.g. by single photon emission computerized tomography. Copyright © 2001 John Wiley & Sons, Ltd. [source] Ptolemy's Planetary Mean Motions RevisitedCENTAURUS, Issue 3 2005Alexander Jones Ptolemy provides two explanations of the origin of his highly precise planetary mean motions in the Almagest, asserting in one set of passages that they were obtained directly from analysis of pairs of observations widely spaced in time, but in another passage that they were derived from period relations expressed as corrections to the well-known Babylonian Goal-Year periods. We show that the latter account is true. Moreover, while some of these period relations may have themselves been calibrated through the observations that Ptolemy cites, those for Mercury and Saturn can be shown to have had a different origin. [source] City Tour Guides: Urban Alchemists at WorkCITY & COMMUNITY, Issue 2 2010Jonathan R. Wynn Urban sociology, often and quite reasonably, emphasizes the effects of large-scale and corporate cultures of cities and yet, at the smaller scale, there is a diverse and complex set of practices that reinvigorate the urban landscape. By pairing ethnographic fieldnotes with interviews, this paper offers a limited rejoinder to these narratives, evincing the lived interactions of one set of characters that reenchants cities. For the purposes of this article, walking tour guides serve as examples of "urban alchemists," and three of their practices are advanced for discussion: their use of myths and revelatory stories to uproot banal visions of the city; their aim to incorporate chance and serendipity into their interactions; and their attempts to transform their participants into "better" urban dwellers. Los Guías Turísticos en las Ciudades: "alquimistas urbanos" trabajando ( Jonathan R. Wynn) Resumen En sociología urbana a menudo se enfatizan (y con razón), los efectos de la cultura corporativa y a gran escala en las ciudades. Sin embargo, hay un conjunto diverso y complejo de prácticas a pequeña escala que también contribuye a revitalizar el entorno urbano. Combinando notas etnográficas y entrevistas realizadas en el área del turismo urbano, este ensayo ofrece una breve respuesta a estas narrativas, mostrando las interacciones de un grupo de personajes que re-encanta las ciudades. Para los fines de este artículo, las y los guías de visitas turísticas de a pie constituyen ejemplos de los llamados "alquimistas urbanos" y se presentan tres de sus prácticas para la discusión: su uso de los mitos y de las historias que revelan el verdadero carácter de la ciudad para eliminar las visiones banales de la misma, su meta de incorporar el azar y los descubrimientos casuales en sus interacciones y sus esfuerzos para transformar a sus participantes en "mejores" habitantes de la ciudad. [source] | ||||||||||||||||||||||||||||