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Particular Use (particular + use)
Selected AbstractsTaurodontism: a review of the condition and endodontic treatment challengesINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2008H. Jafarzadeh Abstract Taurodontism can be defined as a change in tooth shape caused by the failure of Hertwig's epithelial sheath diaphragm to invaginate at the proper horizontal level. An enlarged pulp chamber, apical displacement of the pulpal floor, and no constriction at the level of the cementoenamel junction are the characteristic features. Although permanent molar teeth are most commonly affected, this change can also be seen in both the permanent and deciduous dentition, unilaterally or bilaterally, and in any combination of teeth or quadrants. Whilst it appears most frequently as an isolated anomaly, its association with several syndromes and abnormalities has also been reported. The literature on taurodontism in the context of endodontics up to March 2007 was reviewed using PubMed, MEDLINE and Cumulative Index to Nursing & Allied Health Literature. Despite the clinical challenges in endodontic therapy, taurodontism has received little attention from clinicians. In performing root canal treatment on such teeth, one should appreciate the complexity of the root canal system, canal obliteration and configuration, and the potential for additional root canal systems. Careful exploration of the grooves between all orifices particularly with magnification, use of ultrasonic irrigation; and a modified filling technique are of particular use. [source] Treatment of pediculosis capitis with thiabendazole: a pilot studyINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 12 2003Mohammad Reza Namazi MD Background, Despite the improvement of health standards, head lice infestation remains a problem worldwide. In addition, there is increasing evidence that head lice are becoming resistant to common pediculocides. Aim, To test the potential effectiveness of thiabendazole, a potent and broad-spectrum antiparasitic and scabicidal agent, for the treatment of pediculosis capitis. Methods, Twenty-three female patients, aged 7,12 years, who had active head lice infestation, were treated with oral thiabendazole, 20 mg/kg twice daily for 1 day, with repeat treatment after 10 days. Results, On the 11th day, meticulous hair examination showed that 21 patients had responded to treatment [91%; 95% confidence interval (CI), 71,98%], with 14 showing complete responsiveness (61%; 95% CI, 40,78%). The only adverse reactions observed were nausea and mild dizziness, which occurred in four patients, three of whom took the drug on an empty stomach. Conclusions, Thiabendazole may be a promising treatment for head lice infestation. The primary action of this drug seems to be the inhibition of parasite microtubule polymerization by binding to ,-tubulin. In addition, thiabendazole may interfere with the synaptic transmission of lice through its probable cholinergic effect. As pediculosis capitis is a very communicable disease, the unresponsiveness to thiabendazole could largely be attributed to new infestations during the drug-free interval. Therefore, massive and simultaneous rather than individual and isolated treatments should be used to achieve the epidemiologic control of this ectoparasitosis. As this is a preliminary study, the performance of double-blind, randomized controlled trials on this subject is warranted. Thiabendazole, either alone or in combination with other agents, may prove to be of particular use in areas in which head lice show resistance to common pediculocides. [source] Simultaneous light and small-angle neutron scattering on aggregating concentrated colloidal suspensionsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 1 2003Sara Romer A new sample environment has been developed in order to perform light and small-angle neutron scattering (SANS) simultaneously on colloidal systems. The combination of SANS and diffusing wave spectroscopy (DWS) is of particular use in the high-concentration regime. DWS provides information on the local dynamic properties of the individual particles, whereas SANS gives access to the structural properties on similar length scales. The combination of both methods thus allows one to obtain structural and dynamic information over a very large range of length and time scales. Using this new setup, the onset of aggregation and the sol,gel transition in concentrated destabilized polystyrene sphere suspensions have been investigated. At the gel point, a dramatic change of the particle dynamics from diffusion to a subdiffusive arrested motion is observed. However, while the DWS measurements indicate that dramatic changes in the local dynamics occur over a long period, the SANS pattern quickly reaches its final appearance. The SANS experiments thus indicate that a fluid-like structure is arrested in the course of the gel formation. The data are found to be in good qualitative agreement with computer simulations. [source] GROUPWISE MODELING STUDY OF BACTERIALLY IMPAIRED WATERSHEDS IN TEXAS: CLUSTERING ANALYSIS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2006Sabu Paul ABSTRACT: Under the Clean Water Act (CWA) program, the Texas Commission on Environmental Quality (TCEQ) listed 110 stream segments in the year 2000 with pathogenic bacteria impairment. A study was conducted to evaluate the probable sources of pollution and characterize the watersheds associated with these impaired water bodies. The primary aim of the study was to group the water bodies into clusters having similar watershed characteristics and to examine the possibility of studying them as a group by choosing models for total maximum daily load (TMDL) development based on their characteristics. This approach will help to identify possible sources and determine appropriate models and hence reduce the number of required TMDL studies. This in turn will help in reducing the effort required to restore the health of the impaired water bodies in Texas. The main characteristics considered for the classification of water bodies were land use distribution within the watershed, density of stream network, average distance of land of a particular use to the closest stream, household population, density of on-site sewage facilities (OSSFs), bacterial loading from different types of farm animals and wildlife, and average climatic conditions. The climatic data and observed instream fecal coliform bacteria concentrations were analyzed to evaluate seasonal variability of instream water quality. The grouping of water bodies was carried out using the multivariate statistical techniques of factor analysis/principal component analysis, cluster analysis, and discriminant analysis. The multivariate statistical analysis resulted in six clusters of water bodies. The main factors that differentiated the clusters were found to be bacterial contribution from farm animals and wildlife, density of OSSFs, density of households connected to public sewers, and land use distribution. [source] Identification of bound waters in the solution structure of ribonuclease T1 using the double pulsed field gradient spin-echo NMR technique for selective water excitationMAGNETIC RESONANCE IN CHEMISTRY, Issue 9 2002Mitsuru Tashiro Abstract Novel pulse sequences incorporating the double pulsed field gradient spin-echo technique are presented that have particular use in identifying macromolecular bound water. The use of these sequences is illustrated using ribonuclease T1. Five amide protons cross-relaxing with bound water protons were observed. Examination of the crystal structure revealed that all of these amide protons donate hydrogen bonds or are in close proximity to water molecules with very low temperature factors, indicating that these amide protons are highly correlated with the bound water molecules. This method rapidly provides reliable information for characterizing macromolecular bound water molecules. Copyright © 2002 John Wiley & Sons, Ltd. [source] SNPs in ecological and conservation studies: a test in the Scandinavian wolf populationMOLECULAR ECOLOGY, Issue 2 2005J. M. SEDDON Abstract Single nucleotide polymorphisms (SNPs) have the potential to become the genetic marker of choice in studies of the ecology and conservation of natural populations because of their capacity to access variability across the genome. In this study, we provide one of the first demonstrations of SNP discovery in a wild population in order to address typical issues of importance in ecology and conservation in the recolonized Scandinavian and neighbouring Finnish wolf Canis lupus populations. Using end sequence from BAC (bacterial artificial chromosome) clones specific for dogs, we designed assays for 24 SNP loci, 20 sites of which had previously been shown to be polymorphic in domestic dogs and four sites were newly identified as polymorphic in wolves. Of the 24 assayed loci, 22 SNPs were found to be variable within the Scandinavian population and, importantly, these were able to distinguish individual wolves from one another (unbiased probability of identity of 4.33 × 10,8), providing equivalent results to that derived from 12 variable microsatellites genotyped in the same population. An assignment test shows differentiation between the Scandinavian and neighbouring Finnish wolf populations, although not all known immigrants are accurately identified. An exploration of the misclassification rates in the identification of relationships shows that neither 22 SNP nor 20 microsatellite loci are able to discriminate across single order relationships. Despite the remaining obstacle of SNP discovery in nonmodel organisms, the use of SNPs in ecological and conservation studies is encouraged by the advent of large scale screening methods. Furthermore, the ability to amplify extremely small fragments makes SNPs of particular use for population monitoring, where faecal and other noninvasive samples are routinely used. [source] Combining paternally and maternally inherited mitochondrial DNA for analysis of population structure in musselsMOLECULAR ECOLOGY, Issue 6 2004Robert A. Krebs Abstract Sequence divergence for a fragment of the 16S rRNA gene was compared to identify the advantages in using mitochondrial genes that descend separately through the female and male lineages to examine population structure. The test compared divergence among four local species of freshwater mussels (Unionidae) and was extended to multiple populations of one species, Pyganodon grandis. For the same gene, the male-inherited sequences diverged at a faster rate, producing longer branch lengths in the phylogenies. Of particular use were sequences extracted from P. grandis populations from the southern region of the Lake Erie watershed (Ohio, USA); five male-inherited haplotypes were found. Only one change was observed in the female-inherited form in this region. Therefore, more rapid evolution has occurred in the male form of the gene, and this form provided stronger evidence of geographical isolation among populations. A combination of analyses on haplotypes derived through males and females creates complementary opportunities to identify evolutionary relationships caused by drift and migration in mussels. [source] Fabricated bodies: A model for the somatic false selfTHE INTERNATIONAL JOURNAL OF PSYCHOANALYSIS, Issue 4 2004Peter Goldberg This paper draws attention to a particular use of the body, one in which basic psychical security is achieved through a radical detachment from body vitality, necessitating the creation of a coercive regime of psychosomatic control and autostimulation for purposes of artificial enlivenment of the self. When the personality is organized predominantly along the lines of a systematic dissociation (and then pseudo-integration) of the mental and the somatic realms of psychical life, the psyche-soma undergoes a far-reaching transmutation: the desiring body is eclipsed and replaced with a fabricated body. Clinical observation of this set-up is obscured by the fact that, in these cases, the body is deployed in a ,realistic' manner, rather than in a recognizably symptomatic way. It is, indeed, the hallmark of a successful somatic false-self organization that the colonization of the body is disguised as natural, ego-syntonic and compatible with social norms. The treatment approach requires a broadening of analytic attention to apprehend shifts in states of consciousness and psychophysical cues. [source] APOE is not Associated with Alzheimer Disease: a Cautionary tale of Genotype ImputationANNALS OF HUMAN GENETICS, Issue 3 2010Gary W. Beecham Summary With the advent of publicly available genome-wide genotyping data, the use of genotype imputation methods is becoming increasingly common. These methods are of particular use in joint analyses, where data from different genotyping platforms are imputed to a reference set and combined in a single analysis. We show here that such an analysis can miss strong genetic association signals, such as that of the apolipoprotein-e gene in late-onset Alzheimer disease. This can occur in regions of weak to moderate LD; unobserved SNPs are not imputed with confidence so there is no consensus SNP set on which to perform association tests. Both IMPUTE and Mach software are tested, with similar results. Additionally, we show that a meta-analysis that properly accounts for the genotype uncertainty can recover association signals that were lost under a joint analysis. This shows that joint analyses of imputed genotypes, particularly failure to replicate strong signals, should be considered critically and examined on a case-by-case basis. [source] CFD Modeling of a Bubble Column Reactor Carrying out a Consecutive A , B , C ReactionCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 4 2004J.M. van Baten Abstract In this paper, we develop a CFD model for describing a bubble column reactor for carrying out a consecutive first-order reaction sequence A , B , C. Three reactor configurations, all operating in the homogeneous bubbly regime, were investigated: (I) column diameter DT = 0.1 m, column height HT = 1.1 m, (II) DT = 0.1 m, HT = 2 m, and (III) DT = 1 m, HT = 5 m. Eulerian simulations were carried out for superficial gas velocities UG in the range of 0.005,0.04 m/s, assuming cylindrical axisymmetry. Additionally, for configurations I and III fully three-dimensional transient simulations were carried out for checking the assumption of cylindrical axisymmetry. For the 0.1 m diameter column (configuration I), 2-D axisymmetric and 3-D transient simulations yield nearly the same results for gas holdup ,G, centerline liquid velocity VL(0), conversion of A, ,A, and selectivity to B, SB. In sharp contrast, for the 1 m diameter column (configuration III), there are significant differences in the CFD predictions of ,G, VL(0), ,A, and SB using 2-D and 3-D simulations; the 2-D strategies tend to exaggerate VL(0), and underpredict ,G, ,A, and SB. The transient 3-D simulation results appear to be more realistic. The CFD simulation results for ,A and SB are also compared with a simple analytic model, often employed in practice, in which the gas phase is assumed to be in plug flow and the liquid phase is well mixed. For the smaller diameter columns (configurations I and II) the CFD simulation results for ,A are in excellent agreement with the analytic model, but for the larger diameter column the analytic model is somewhat optimistic. There are two reasons for this deviation. Firstly, the gas phase is not in perfect plug flow and secondly, the liquid phase is not perfectly mixed. The computational results obtained in this paper demonstrate the power of CFD for predicting the performance of bubble column reactors. Of particular use is the ability of CFD to describe scale effects. [source] Laws of the StreetCITY & SOCIETY, Issue 2 2009MARIANA VALVERDE Abstract Critical urban studies scholarship has documented numerous particular uses and misuses of law in urban contexts. This article argues that case studies of specific campaigns about urban space are insufficient, and that if we want to understand the quotidian negotiation of urban norms and urban order we need to undertake systematic studies of the everyday, largely unpublicized workings of the whole array of municipal legal tools that influence how spaces and activities are organized. This argument is pursued by way of an inventory of all the legal forces converging on a single streetcorner, the intersection of Bloor and Saint George streets in Toronto. Since Toronto's legal arsenal is very similar to that used by North American cities generally, the inventory is of more than local interest. [source] | ||||||||||||||||