Home About us Contact
|
Home About us Contact | ||
|
|
||
Appropriate Tool (appropriate + tool)
Selected AbstractsHow should peripheral neuropathy be assessed in people with diabetes in primary care?DIABETIC MEDICINE, Issue 5 2003A population-based comparison of four measures Abstract Aims To test the accuracy of four measures of peripheral diabetic neuropathy in a primary care population. Methods Type 2 diabetic (n = 544) and 544 non-diabetic participants aged 45,76 years were randomly selected from general practice registers. Neuropathy was assessed using vibration threshold (VT) and scores for light touch, thermal sense and modified Michigan Neuropathy Screening Instrument questionnaire. These measures were assessed for variation with diabetes status, age, diabetes duration, HbA1c, and presence of retinopathy and nephropathy. Light touch, thermal sense and questionnaire scores were assessed against VT using ROC curve analysis. Results Only VT and light touch were different between diabetic and non-diabetic groups (P = 0.02 and < 0.0001, respectively). All measures were significantly associated with diabetes duration and retinopathy, and all except questionnaire score (P = 0.14) with age. None was associated with nephropathy and only questionnaire score was associated with HbA1c (P = 0.033). VT varied as expected across scores of light touch (,2 = 41.65, P = 0.0001), thermal sense (,2 = 15.86, P = 0.015) and questionnaire (,2 = 21.22, P = 0.047). Area under the curve values for light touch, thermal and questionnaire scores were 0.72 (95% confidence interval (CI) 0.63, 0.82), 0.63 (95% CI 0.52, 0.73) and 0.64 (95% CI 0.53, 0.74), respectively. Conclusions All measures had associations with risk factors for neuropathy, but light touch score (monofilament) had the strongest association with vibration threshold (the chosen gold standard) and thus appeared the most appropriate tool for use in primary care, because of its validity and simplicity of use. Diabet. Med. 20, 368,374 (2003) [source] Sphere contact fatigue of a coarse-grained Al2O3 ceramicFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 11 2006T. FETT ABSTRACT The opposite sphere test is an appropriate tool to determine crack-growth exponents for fatigue under repeated contact loading. Lifetime measurements for a coarse-grained Al2O3 are reported. To explain the fatigue exponents that strongly deviated from those obtained in cyclic bending tests, a fracture mechanics analysis was carried out. It was aimed at determining the correct stress intensity factor solution for the tests, including limited dimensions of test specimens deviating from the case of a cone crack in a half space. Cone crack development was observed microscopically and the related stress intensity factors were computed for the observed crack shape. For modelling the fatigue behaviour, it is assumed that the fatigue effect is influenced by a reduction of the shielding term of crack growth resistance due to periodical friction between the grain-interlock bridges in coarse-grained alumina. This results in a loss of traction at the junctions, crack tip shielding is reduced, and the effective load at the crack tip is increased. [source] Zeolite Catalysts with Tunable Hierarchy Factor by Pore-Growth ModeratorsADVANCED FUNCTIONAL MATERIALS, Issue 24 2009Javier Pérez-Ramírez Abstract The design of hierarchical zeolite catalysts is attempted through the maximization of the hierarchy factor (HF); that is, by enhancing the mesopore surface area without severe penalization of the micropore volume. For this purpose, a novel desilication variant involving NaOH treatment of ZSM-5 in the presence of quaternary ammonium cations is developed. The organic cation (TPA+ or TBA+) acts as a pore-growth moderator in the crystal by OH, -assisted silicon extraction, largely protecting the zeolite crystal during the demetallation process. The protective effect is not seen when using cations that are able to enter the micropores, such as TMA+ Engineering the pore structure at the micro- and mesolevel is essential to optimize transport properties and catalytic performance, as demonstrated in the benzene alkylation with ethylene, a representative mass-transfer limited reaction. The hierarchy factor is an appropriate tool to classify hierarchically structured materials. The latter point is of wide interest to the scientific community as it not only embraces mesoporous zeolites obtained by desilication methods but it also enables to quantitatively compare and correlate various materials obtained by different synthetic methodologies. [source] 2D data modelling by electrical resistivity tomography for complex subsurface geologyGEOPHYSICAL PROSPECTING, Issue 2 2006E. Cardarelli ABSTRACT A new tool for two-dimensional apparent-resistivity data modelling and inversion is presented. The study is developed according to the idea that the best way to deal with ill-posedness of geoelectrical inverse problems lies in constructing algorithms which allow a flexible control of the physical and mathematical elements involved in the resolution. The forward problem is solved through a finite-difference algorithm, whose main features are a versatile user-defined discretization of the domain and a new approach to the solution of the inverse Fourier transform. The inversion procedure is based on an iterative smoothness-constrained least-squares algorithm. As mentioned, the code is constructed to ensure flexibility in resolution. This is first achieved by starting the inversion from an arbitrarily defined model. In our approach, a Jacobian matrix is calculated at each iteration, using a generalization of Cohn's network sensitivity theorem. Another versatile feature is the issue of introducing a priori information about the solution. Regions of the domain can be constrained to vary between two limits (the lower and upper bounds) by using inequality constraints. A second possibility is to include the starting model in the objective function used to determine an improved estimate of the unknown parameters and to constrain the solution to the above model. Furthermore, the possibility either of defining a discretization of the domain that exactly fits the underground structures or of refining the mesh of the grid certainly leads to more accurate solutions. Control on the mathematical elements in the inversion algorithm is also allowed. The smoothness matrix can be modified in order to penalize roughness in any one direction. An empirical way of assigning the regularization parameter (damping) is defined, but the user can also decide to assign it manually at each iteration. An appropriate tool was constructed with the purpose of handling the inversion results, for example to correct reconstructed models and to check the effects of such changes on the calculated apparent resistivity. Tests on synthetic and real data, in particular in handling indeterminate cases, show that the flexible approach is a good way to build a detailed picture of the prospected area. [source] The utility of the Dutch Arthritis Impact Measurement Scales 2 for assessing health status in individuals with haemophilia: a pilot studyHAEMOPHILIA, Issue 6 2000N. L. U. Van Meeteren The aim of this pilot study was to examine the usefulness of the Dutch version of the Arthritis Impact Measurement Scales 2 (D-AIMS2)in assessing the health status of Dutch individuals with haemophilia. Sixty-eight individuals with mild, moderate, and severe haemophilia attending our clinic for their annual check-up participated. They first completed the Canadian Occupational Performance Measure (COPM). The D-AIMS2 was filled in afterwards at home. With the COPM, individuals rated their specific problematic activities of daily life (ADL), as well as the severity and importance of each problem. The D-AIMS2 is a comprehensive, self-administered questionnaire that evaluates functional health status. Fifty-seven individuals completed and returned the D-AIMS2. Reliability analysis demonstrated good internal consistency for the scales (Cronbach's ,=0.76,1.00), as well as for the components (,=0.80,0.88), except for the component ,social interaction' (,=0.44). Criterion validity of the D-AIMS2 was assessed by comparison with COPM outcomes; 80% of the problematic ADLs were included in the questionnaire, 20% were missing. Correlations between the D-AIMS2 components ,physical health' and ,symptoms' with predicted scores of those individuals by a highly experienced physiotherapist (r=0.63 and 0.53, respectively) substantiated its concurrent validity. Based on these results we concluded that the D-AIMS2, with minor adjustments, can be an appropriate tool for assessing the health status of Dutch haemophilia patients. [source] The usefulness of sensitivity analysis for predicting the effects of cat predation on the population dynamics of their avian preyIBIS, Issue 2008MAIREAD M. MACLEAN Sensitivity analyses of population projection matrix (PPM) models are often used to identify life-history perturbations that will most influence a population's future dynamics. Sensitivities are linear extrapolations of the relationship between a population's growth rate and perturbations to its demographic parameters. Their effectiveness depends on the validity of the assumption of linearity. Here we assess whether sensitivity analysis is an appropriate tool to investigate the effect of predation by cats on the population growth rates of their avian prey. We assess whether predation by cats leads to non-linear effects on population growth and compare population growth rates predicted by sensitivity analysis with those predicted by a non-linear simulation. For a two-stage, age-classified House Sparrow Passer domesticus PPM slight non-linearity arose when PPM elements were perturbed, but perturbation to the vital rates underlying the matrix elements had a linear impact on population growth rate. We found a similar effect with a slightly larger three-stage, age-classified PPM for a Winter Wren Troglodytes troglodytes population perturbed by cat predation. For some avian species, predation by cats may cause linear or only slightly nonlinear impacts on population growth rates. For these species, sensitivity analysis appears to be a useful conservation tool. However, further work on multiple perturbations to avian prey species with more complicated life histories and higher-dimension PPM models is required. [source] ,It's the identification, stupid': profiling senior public service managers for training and developmentINTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 2 2002Gambhir Bhatta A review of practices of senior management development across the upper echelons of the public services of major jurisdictions shows that while the need to develop leaders is universally recognised by governments, there are still considerable gaps in the development function. One of the key gaps the article argues that is central to the training and development function is that of identification and targeting of individuals. A profiling protocol is presented that is argued could be an appropriate tool for governments to consider as they seek to link the desired competencies with the career aspirations of their public service senior managers. [source] Phase equilibria modelling of kyanite-bearing anatectic paragneisses from the central Grenville ProvinceJOURNAL OF METAMORPHIC GEOLOGY, Issue 8 2008A. INDARES Abstract Kyanite-bearing paragneisses from the Manicouagan Imbricate Zone and its footwall (high- P belt of the central Grenville Province) preserve evidence of partial melting with development of metamorphic textures involving biotite,garnet ± kyanite ± plagioclase ± K-feldspar,quartz. Garnet in these rocks displays a variety of zoning patterns with respect to Ca. Pseudosection modelling in the Na2O,CaO,K2O,FeO,MgO,Al2O3,SiO2,H2O,TiO2,O (NCKFMASHTO) system using measured bulk rock compositions accounts for the textural evolution of two aluminous and two sub-aluminous samples from the presumed thermal peak to conditions at which retained melt solidified. The prograde features are best explained by pseudosections calculated with compositions to account for melt loss. The intersection of isopleths of grossular content and Fe/(Fe + Mg) relating to large porphyroblasts of garnet provide constraints on the P,T conditions of the metamorphic peak. These P,T estimates are considered to be minima because of the potential for diffusional modification of the composition of garnet at high- T and during the early stages of cooling. However, they are consistent with textural observations and pseudosection topology, with peak assemblages best preserved in rocks for which the calculated pseudosections predict only small changes in mineral proportions in the P,T interval, in which retrograde reactions are inferred to have occurred between the thermal peak and the solidus. Maximum P,T conditions (14.5,15.5 kbar and 840,890 °C) and steep retrograde P,T paths inferred for rocks from the Manicouagan Imbricate Zone are comparable with those determined for mafic rocks from the same area. In contrast, maximum P,T conditions of 12.5,13 kbar and 815,830 °C and flatter P,T paths are inferred for the rocks of the footwall to the Manicouagan Imbricate Zone. The general consistency between textures, mineral compositions and the topologies of the calculated pseudosections suggests that the pseudosection approach is an appropriate tool for inferring the P,T evolution of high- P anatectic quartzo-feldspathic rocks. [source] Evaluation of a combined penetrometer for simultaneous measurement of penetration resistance and soil water contentJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 6 2004Yurui Sun Abstract A combined penetrometer is an appropriate tool to measure the soil cone resistance and the water-content profile. As a relatively new technique, a combined capacitance-penetrometer for the simultaneous measurement of cone index and soil water content was developed at the Department of Agricultural Engineering of Bonn University in 2002. The objective of this study was the evaluation of the effectiveness and applicability of the innovated penetrometer with a focus on three aspects: (1) A capacitance sensor with two electrode configurations was calibrated for silt loam, sandy loam, and sand. The calibration results show that both electrode configurations have sufficient water-content sensitivity, but soil-specific calibrations seem necessary. (2) Under laboratory conditions, the dynamic resolution and response of the capacitance-penetrometer were validated, and its radius of influence was determined. (3) The field measurement results demonstrate that this measurement technique can be used to improve the interpretation quality of soil cone index data. Bewertung eines Penetrometers zur gleichzeitigen Bestimmung von Eindringwiderstand und Bodenfeuchte Für die Ermittlung von Bodenprofilen für den Eindringwiderstand und die Bodenfeuchte erscheint die Kombination aus Penetrometer und Bodenfeuchtesensor als geeignete Lösung. Ein solcher Kombinationssensor wurde im Jahr 2002 am Institut für Landtechnik der Universität Bonn für die simultane Messung des Eindringwiderstandes und der Bodenfeuchte entwickelt. In diesem Beitrag wird die Tauglichkeit und Anwendbarkeit für Feldmessungen in folgenden Schritten dargestellt: (1) Ein kapazitiver Sensor mit zwei Elektrodenkonfigurationen wurde für die drei Bodenarten schluffiger Lehm, sandiger Lehm und Sand kalibiriert. Die Kalibrationsgleichungen zeigen, dass beide Elektrodenanordnungen über ausreichende Empfindlichkeit zur Bodenfeuchtemessung verfügen. Es sind aber bodenartspezifische Kalibrierungen notwendig. (2) Die dynamische Auflösung und das Ansprechverhalten des Feuchtesensors wurden für beide Elektrodenanordnungen untersucht, und die Ausbreitung des dielektrischen Feldes wurde bestimmt. (3) Die Ergebnisse der Messungen im gewachsenen Boden zeigen, dass die Messmethode zur Verbesserung der Interpretation der Konus-Indexwerte herangezogen werden kann. [source] Approximate Bayesian inference for latent Gaussian models by using integrated nested Laplace approximationsJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES B (STATISTICAL METHODOLOGY), Issue 2 2009Håvard Rue Summary., Structured additive regression models are perhaps the most commonly used class of models in statistical applications. It includes, among others, (generalized) linear models, (generalized) additive models, smoothing spline models, state space models, semiparametric regression, spatial and spatiotemporal models, log-Gaussian Cox processes and geostatistical and geoadditive models. We consider approximate Bayesian inference in a popular subset of structured additive regression models, latent Gaussian models, where the latent field is Gaussian, controlled by a few hyperparameters and with non-Gaussian response variables. The posterior marginals are not available in closed form owing to the non-Gaussian response variables. For such models, Markov chain Monte Carlo methods can be implemented, but they are not without problems, in terms of both convergence and computational time. In some practical applications, the extent of these problems is such that Markov chain Monte Carlo sampling is simply not an appropriate tool for routine analysis. We show that, by using an integrated nested Laplace approximation and its simplified version, we can directly compute very accurate approximations to the posterior marginals. The main benefit of these approximations is computational: where Markov chain Monte Carlo algorithms need hours or days to run, our approximations provide more precise estimates in seconds or minutes. Another advantage with our approach is its generality, which makes it possible to perform Bayesian analysis in an automatic, streamlined way, and to compute model comparison criteria and various predictive measures so that models can be compared and the model under study can be challenged. [source] From personal reflection to social positioning: the development of a transformational model of professional education in midwiferyNURSING INQUIRY, Issue 4 2002Diane Phillips A transformational model of professional identity formation, anchored and globalized in workplace conversations, is advanced. Whilst the need to theorize the aims and methods of clinical education has been served by the techno-rational platform of ,reflective practice', this platform does not provide an adequate psychological tool to explore the dynamics of social episodes in professional learning and this led us to positioning theory. Positioning theory is one such appropriate tool in which individuals metaphorically locate themselves within discursive action in everyday conversations to do with personal positioning, institutional practices and societal rhetoric. This paper develops the case for researching social episodes in clinical education through professional conversations where midwifery students, in practice settings, are encouraged to account for their moment-by-moment interactions with their preceptors/midwives and university mentors. It is our belief that the reflection elaborated by positioning theory should be considered as the new epistemology for professional education where professional conversations are key to transformative learning processes for persons and institutions. [source] An Improved Algorithm for Satellite-derived UV Radiation,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 1 2003Sigrid Wuttke ABSTRACT The improved algorithm surface irradiance derived from a range of satellite-based sensors (SIDES) is presented in this article. It calculates various types of surface UV intensities, such as biologically weighted or unweighted UV spectra, integrated doses or irradiance at specific wavelengths, using data from satellite instruments. These surface UV data are mainly useful for environmental impact or process studies where high accuracy or a high temporal resolution is required. In contrast to several previous studies, SIDES has been validated with spectral measurements. By this method an averaging of positive or negative deviations over the complete wavelength range is avoided. This is especially important for UV wavelengths around 300 nm where biological effectiveness is highest. The results of SIDES deviate less than 7% from ground-based observations for wavelengths between 295 and 400 nm. In contrast, the corresponding deviations of the joint research center algorithm escalate for shorter wavelengths, reaching 35% at 295 nm. This large deviation is due to an inaccurate interpolation procedure that has been detected by spectral analysis. Thus, spectral validation is demonstrated to be an appropriate tool to detect weaknesses in such an algorithm and provides information essential for improvement. [source] Analysis of nodulation kinetics in Frankia,Discaria trinervis symbiosis reveals different factors involved in the nodulation processPHYSIOLOGIA PLANTARUM, Issue 4 2008Luciano Andrés Gabbarini The induction of root nodule development in actinorhizal symbiosis would depend on the concentration of factors produced by the bacteria and the plant. A detailed analysis of nodulation description parameters revealed different factors related to the nodulation process. The initial time for nodulation (t0), the initial nodulation rate (v0) and the total time of nodule development (tNOD) were defined and consequently quantified in different experimental conditions: co-inoculation of Discaria trinervis with increasing concentrations of different non-infective bacteria together with the full compatible infective Frankia strain (the indicator strain) used at a limiting concentration or by changing plant factor(s) concentration. All the above nodulation parameters were modified by changing doses of full compatibility infective strain Frankia BCU110501; v0 appears to be an expression of symbiotic recognition between partners as only fully symbiotic indicator Frankia BCU110501 was able to change it; t0 seems not to reflect symbiotic recognition because it can also be modified by non-infective Frankia but suggest the existence of a basic level of plant microbe recognition. The initial time for nodulation t0, reflecting the time required for the early interactions toward nodulation, is an inverse measure of the ability to establish early interactions toward nodulation. The increase in plant factors concentration also reduces t0 values, suggesting that a plant factor is involved and favors very early interactions. Increases in plant factors concentration also modify the final number of nodules per plant and the nodule cluster profile along the taproot as an expression of the autoregulation phenomenon. Meanwhile, Frankia inoculums' concentration, either infective or not, modified tNOD in an opposite way plant factors did. In conclusion, the analysis of nodulation kinetics appears to be an appropriate tool to investigate factors involved in the symbiotic interaction leading to the formation of nitrogen-fixing nodules. [source] Microdissection or Microspot CO2 Laser for Limited Vocal Fold Benign Lesions: A Prospective Randomized Trial,THE LARYNGOSCOPE, Issue S92 2000Michael S. Benninger MD CO2 lasers have become an important technological advance and an integral tool for the laryngeal surgeon since the 1960s. Surgeons have used lasers for a variety of benign and malignant lesions in the larynx with good success. With better understanding of the microarchitecture of the vocal folds and the recognition of heat distribution into surrounding tissues that occurs with the use of standard CO2 lasers, questions and concerns have been raised regarding the use of the CO2 laser for benign lesions of the vocal folds. With the advent of the microspot CO2 laser with a spot size of less than 250 ,m, the potential heat distribution to the deeper layers of the lamina propria has been reduced. The microspot CO2 laser has been suggested to be an appropriate tool for the excision of superficial benign lesions of the vocal fold and may be considered as an appropriate treatment alternative to microdissection. Only a limited number of studies have compared the efficacy of microdissection versus microspot CO2 laser surgery in the larynx, and no prospective, randomized trials have been performed. Objective This study was designed to compare microspot CO2 laser excision and microdissection for superficial benign lesions confined to the free margin of the vocal fold. Study Design: A randomized, prospective trial comparing microspot CO2 laser excision and microdissection in the removal of nodules, polyps, and mucous retention cysts of the vocal fold. Methods Acoustic and aerodynamic measures and videostroboscopic and perceptual audio recordings evaluated by a panel of blinded viewers and listeners were studied preoperatively and 2 to 3 weeks and 5 to 12 weeks postoperatively. Surgical and recovery times were compared between the two groups. Results Thirty-seven patients met selection criteria and were enrolled, 21 in the microdissection group and 16 in the laser excision group. Significant improvements in videostroboscopic parameters were found over time in both groups. Significant improvements were noted for perceptual analysis over time for the laser excision group with nonsignificant improvements over time for the microdissection group. There was no difference in any measure between laser excision and microdissection at the two postoperative visits. There was no difference in surgical or recovery time between laser excision and microdissection. Acoustic and aerodynamic parameters were noncontributory in evaluating outcomes of treatment, since most values were normal before surgery. Conclusion No differences in clinical outcomes are identified when comparing microdissection with laser excision of nodules, polyps, and mucous retention cysts of the vocal folds. [source] Development and validation of a questionnaire measuring quality of life in primary caregivers of children with atopic dermatitis (QPCAD)BRITISH JOURNAL OF DERMATOLOGY, Issue 3 2009K. Kondo-Endo Summary Background, Disease-specific health-related quality of life (HRQoL) instruments for primary caregivers of children with atopic dermatitis are useful in evaluating the efficacy of treatment in clinical practice and study. However, no such scale has been available in Japan. Objectives, To develop and validate a self-administered instrument specifically designed to measure quality of life in primary caregivers of children with atopic dermatitis (QPCAD). Methods, This study consisted of three successive phases: the item generation phase, pilot test phase and validation phase. In the item generation phase, questionnaire items were derived from 33 qualitative interviews with primary caregivers. In the pilot test phase, the face and content validity of the preliminary scale were assessed (n = 33). In the validation phase, the questionnaire was finalized and assessed in terms of statistical performance (n = 416). Results, The QPCAD included 19 items in the following categories: ,exhaustion', ,worry about atopic dermatitis', ,family cooperation' and ,achievement'. The reliability of internal consistency was fair (Cronbach's alpha coefficients 0·66,0·87). The QPCAD subscales and total score were significantly correlated with psychological health, physical health, anxiety, depression and severity score, with mild to moderate correlation coefficients. Test,retest reliability and responsiveness to change in severity were also satisfactory. Conclusions, The QPCAD is an appropriate tool for assessing HRQoL of primary caregivers of children with atopic dermatitis in clinical practice and clinical trials. [source] Synthesis of Benzaldehyde-Functionalized Glycans: A Novel Approach Towards Glyco-SAMs as a Tool for Surface Plasmon Resonance StudiesCHEMISTRY - A EUROPEAN JOURNAL, Issue 23 2010Sebastian Kopitzki Dipl.-Chem. Abstract In recent years the interest in tools for investigating carbohydrate,protein (CPI) and carbohydrate-carbohydrate interactions (CCI) has increased significantly. For the investigation of CPI and CCI, several techniques employing different linking methods are available. Surface plasmon resonance (SPR) imaging is a most appropriate tool for analyzing the formation of self-assembled monolayers (SAM) of carbohydrate derivatives, which can mimic the glycocalyx. In contrast to the SPR imaging methods used previously to analyze CPI and CCI, the novel approach reported herein allows a facile and rapid synthesis of linker spacers and carbohydrate derivatives and enhances the binding event by controlling the amount and orientation of ligand. For immobilization on biorepulsive amino-functionalized SPR chips by reductive amination, diverse aldehyde-functionalized glycan structures (glucose, galactose, mannose, glucosamine, cellobiose, lactose, and lactosamine) have been synthesized in several facile steps that include olefin metathesis. Effective immobilization and the first binding studies are presented for the lectin concanavalin A. [source] 4,,,-Acetylvitexin-2,- O -rhamnoside, Isoorientin, Orientin, and 8-Methoxykaempferol-3- O -glucoside as Markers for the Differentiation of Crataegus monogyna and Crataegus pentagyna from Crataegus laevigata (Rosaceae)CHEMISTRY & BIODIVERSITY, Issue 12 2007Sonja Prinz Abstract In our chemotaxonomic investigation of pharmaceutically relevant Crataegus species, the qualitative and quantitative flavonoid fingerprint of Crataegus monogyna and C. pentagyna is presented. Six flavonoids were identified as vitexin-2,- O -rhamnoside (1), vitexin (2), isovitexin (3), rutin (4), hyperoside (5), and isoquercitrin (6). Besides the verification of the main compounds isoorientin (7) and orientin (8) in C. pentagyna, further four flavonoids were isolated and identified as isoorientin-2,- O -rhamnoside (9), orientin-2,- O -rhamnoside (10), isovitexin-2,- O -rhamnoside (11), and 8-methoxykaempferol-3- O -glucoside (12) by means of 1D- and 2D-NMR, MS, and UV analyses. Compound 12 was isolated for the first time from C. pentagyna. In contrast to C. pentagyna, C. monogyna samples were predominated by 4,,,-acetylvitexin-2,- O -rhamnoside (13), which was missing in C. pentagyna. Hence, 13 represents an interesting compound for chemotaxonomy of C. monogyna, whereas the main flavonoids 7, 8, and 12 could be proposed as markers for C. pentagyna. The absence of 7, 8, 12, and 13 in C. laevigata offers an appropriate tool for additional differentiation from C. monogyna and C. pentagyna, and for sample identification and quality control of the three main Crataegus species used in European phytotherapy. [source] Spatiotemporal distribution of heparan sulfate epitopes during myogenesis and synaptogenesis: A study in developing mouse intercostal muscleDEVELOPMENTAL DYNAMICS, Issue 1 2002Guido J. Jenniskens Abstract Formation of a basal lamina (BL) ensheathing developing skeletal muscle cells is one of the earliest events in mammalian skeletal muscle myogenesis. BL-resident heparan sulfate proteoglycans have been implicated in various processes during myogenesis, including synaptic differentiation. However, attention has focused on the proteoglycan protein core, ignoring the glycosaminoglycan moiety mainly because of a lack of appropriate tools. Recently, we selected a panel of anti,heparan sulfate antibodies applied here to study the spatiotemporal distribution of specific heparan sulfate (HS) epitopes during myogenesis. In mouse intercostal muscle at embryonic day (E14), formation of acetylcholine receptor clusters at synaptic sites coincides with HS deposition. Although some HS epitopes show a general appearance throughout the BL, one epitope preferably clusters at synaptic sites but does so only from E16 onward. During elongation and maturation of primary myotubes, a process preceding secondary myotube development, significant changes in the HS epitope constitution of both synaptic and extrasynaptic BL were observed. As a whole, the data presented here strengthen previous observations on developmental regulation by BL components, and add to the putative roles of specific HS epitopes in myogenesis and synaptogenesis. © 2002 Wiley-Liss, Inc. [source] Explanation And Thought Experiments In HistoryHISTORY AND THEORY, Issue 1 2003Tim De Mey Although interest in them is clearly growing, most professional historians do not accept thought experiments as appropriate tools. Advocates of the deliberate use of thought experiments in history argue that without counterfactuals, causal attributions in history do not make sense. Whereas such arguments play upon the meaning of causation in history, this article focuses on the reasoning processes by which historians arrive at causal explanations. First, we discuss the roles thought experiments play in arriving at explanations of both facts and contrasts. Then, we pinpoint the functions thought experiments fulfill in arriving at weighted explanations of contrasts. [source] Current Issues in the Economics of Groundwater Resource ManagementJOURNAL OF ECONOMIC SURVEYS, Issue 5 2004Phoebe Koundouri Abstract., The issue of groundwater management remains a practical concern in many regions throughout the world, while water managers continue to grapple with the question of how to manage this resource. In this article, we attempt to bring the most advanced and appropriate tools to bear on the issue of resource allocation involving groundwater. Our objective is to demonstrate the state of the art in the literature on ways to think about this complex resource and to deal with the important economic issues emanating from its complexity. We present the conceptual framework within which economists examine the elements interacting in the management of groundwater resources, indicate why the role of the market is limited with respect to the price of this very complex resource, and point to the mechanisms that can pull competitive groundwater price and quality-graded quantity of groundwater in line with their equilibrium levels. In particular, we critically review economic models of groundwater use, examine the potential for groundwater management, discuss the difficulties encountered in the estimation of the relevant control variables of such models, and identify the advantages and limitations of the instruments devised for the efficient use (allocation) of this resource. Finally, we argue that devised regulatory schemes usually ignore the information and knowledge needed for their implementation, and we suggest a core of conditions necessary for successful groundwater management reforms. [source] Biological foundation for periodontitis as a potential risk factor for atherosclerosisJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2005Yong-Hee P. Chun Objectives:, Links between periodontal diseases and systemic diseases have been well documented by epidemiological studies. Recently, research has shifted to elucidating the biologic mechanism for a causal relationship. One focus of interest is atherosclerosis, the underlying event of cardiovascular diseases due to its serious health impact. However, it is still not clear whether periodontopathic pathogens are truly etiologic agents or ubiquitous bystanders. This article reviews the current understanding about the molecular biological interactions between periodontal disease and atherosclerosis and the biological plausibility of periodontitis as a potential risk factor for cardiovascular disease. Materials and methods:, The current literature regarding periodontal diseases and atherosclerosis and coronary vascular disease was searched using the Medline and PubMed databases. Results:,In vitro experiments and animal models are appropriate tools to investigate the biological interactions between periodontal disease and atherosclerosis at the cell molecular level. The concepts linking both pathologies refer to inflammatory response, immune responses, and hemostasis. In particular, Porphyromonas gingivalis appears to have unique, versatile pathogenic properties. Whether or not these findings from isolated cells or animal models are applicable in humans with genetic and environmental variations is yet to be determined. Likewise, the benefit from periodontal therapy on the development of atherosclerosis is unclear. Approaches targeting inflammatory and immune responses of periodontitis and atherosclerosis simultaneously are very intriguing. Conclusion:, An emerging concept suggests that a pathogenic burden from different sources might overcome an individual threshold culminating in clinical sequela. P. gingivalis contributes directly and indirectly to atherosclerosis. [source] Towards a fuller understanding of mosquito behaviour: use of electrocuting grids to compare the odour-orientated responses of Anopheles arabiensis and An. quadriannulatus in the fieldMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2008S. J. TORR Abstract The epidemiological role of and control options for any mosquito species depend on its degree of ,anthropophily'. However, the behavioural basis of this term is poorly understood. Accordingly, studies in Zimbabwe quantified the effects of natural odours from cattle and humans, and synthetic components of these odours, on the attraction, entry and landing responses of Anopheles arabiensis Giles (Diptera: Culicidae) and Anopheles quadriannulatus Theobald. The numbers of mosquitoes attracted to human or cattle odour were compared using electrocuting nets (E-nets), and entry responses were gauged by the catch from an odour-baited entry trap (OBET) relative to that from an odour-baited E-net. Landing responses were estimated by comparing the catches from E-nets and cloth targets covered with an electrocuting grid. For An. arabiensis, E-nets baited with odour from a single ox or a single man caught similar numbers, and increasing the dose of human odour from one to three men increased the catch four-fold. For An. quadriannulatus, catches from E-nets increased up to six-fold in the progression: man, three men, ox, and man + ox, with catch being correlated with bait mass. Entry responses of An. arabiensis were stronger with human odour (entry response 62%) than with ox odour (6%) or a mixture of cattle and human odours (15%). For An. quadriannulatus, the entry response was low (< 2%) with both cattle and human odour. Anopheles arabiensis did not exhibit a strong entry response to carbon dioxide (CO2) (0.2,2 L/min). The trends observed using OBETs and E-nets also applied to mosquitoes approaching and entering a hut. Catches from an electrocuting target baited with either CO2 or a blend of acetone, 1-octen-3-ol, 4-methylphenol and 3-n-propylphenol , components of natural ox odour , showed that virtually all mosquitoes arriving there alighted on it. The propensity of An. arabiensis to enter human habitation seemed to be mediated by odours other than CO2 alone. Characterizing ,anthropophily' by comparing the numbers of mosquitoes caught by traps baited with different host odours can lead to spurious conclusions; OBETs baited with human odour caught around two to four times more An. arabiensis than cattle-baited OBETs, whereas a human-baited E-net caught less (, 0.7) An. arabiensis than a cattle-baited E-net. Similar caution is warranted for other species of mosquito vectors. A fuller understanding of how to exploit mosquito behaviour for control and surveys requires wider approaches and more use of appropriate tools. [source] Embedding 3D models of biological specimens in PDF publicationsMICROSCOPY RESEARCH AND TECHNIQUE, Issue 11 2008Bernhard Ruthensteiner Abstract By providing two examples, the option for embedding 3D models in electronic versions of life science publications is presented. These examples, presumably representing the first such models published, are developmental stages of an evertebrate (Patella caerulea, Mollusca) and a vertebrate species (Psetta maxima, Teleostei) obtained from histological section series reconstruction processed with the software package Amira. These surface rendering models are particularly suitable for a PDF file because they can easily be transformed to a file format required and components may be conveniently combined and hierarchically arranged. All methodological steps starting from specimen preparation until embedding of resulting models in PDF files with emphasis on conversion of Amira data to the appropriate 3D file format are explained. Usability of 3D models in PDF documents is exemplified and advantages over 2D illustrations are discussed, including better explanation capabilities for spatial arrangements, higher information contents, and limiting options for disguising results by authors. Possibilities for additional applications reaching far beyond the examples presented are suggested. Problems such as long-term compatibility of file format and hardware plus software, editing and embedding of files, file size and differences in information contents between printed and electronic version will likely be overcome by technical development and increasing tendency toward electronic at the cost of printed publications. Since 3D visualization plays an increasing role in manifold disciplines of science and appropriate tools for the popular PDF format are readily available, we propose routine application of this way of illustration in electronic life science papers. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc. [source] Importance of Anterograde Visualization of the Coronary Venous Network by Selective Left Coronary Angiography Prior To ResynchronizationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2007NICOLAS DELARCHE M.D. Background: Understanding of coronary anatomy is essential to the advancement of cardiac resynchronization therapy (CRT) techniques. We determined whether the difficulties associated with catheterization of the coronary sinus (CS) and its lateral branches could be overcome by a preliminary angiographical study of the coronary venous system carried out during a pre-operative coronary angiography with examination of venous return. Methods and Results: All patients were scheduled for an exploratory angiography procedure and indicated for CRT. Group A patients were implanted with a CRT device after a right arterial angiographical procedure while group B patients had a selective left angiogram including examination of venous return. Data analyzed in group B were: position of CS ostium, number and distribution of lateral branches, and ability to preselect a marginal vein suitable for catheterization. Subsequent device implantation was guided by these parameters. A total of 96 and 89 patients were included in groups A and B, respectively. Implantation success rates were not different (98% and 100%, respectively), but CS catheterization time was reduced in group B (6 minutes vs 4 minutes; P < 10,6) as well as total time required to position the left ventricular lead (25 minutes vs 15 minutes; P < 10,6), fluoroscopy exposure (7 minutes vs 5 minutes; P < 10,6), and volume of contrast medium required (45 mL vs 15 mL; P < 10,6). Conclusion: A coronary angiographical study, including examination of the coronary venous return prior to implantation of a CRT device, can simplify the device implant and allows patient-specific preselection of appropriate tools for the procedure. [source] Evaluation of a training to improve management of pediatric overweightTHE JOURNAL OF CONTINUING EDUCATION IN THE HEALTH PROFESSIONS, Issue 4 2005Josephine Hinchman MPH Research Associate Abstract Introduction: Despite widespread concern about pediatric obesity, health care professionals report low proficiency for identifying and treating this condition. This paper reports on the evaluation of pediatric overweight assessment and management training for clinicians and staff in a managed care system. The training was evaluated for its impact on assessment practices and utilization of management tools. Methods: A delayed-control design was utilized to measure the effects of two 60-minute interactive Continuing Medical education (CME) trainings for the pediatric health care teams. Chart abstraction was conducted at 0-, 3- and 6-months after training, recording the proportion of charts containing the recommended assessment methods and management tools. Results: The training was associated with a significant increase in the utilization of some tools and practices, including charting BMI-for-age percentile (p<0.001) and using a nutrition and activity self-history form (p<0.001). Overall, from baseline to 3-months post training, charting BMI-for-age percentiles increased from zero to 25.2% and utilization of the self-history form increased from zero to 35.3%. These increases were sustained at 6-months post training. Other tools guiding clinician counseling were less widely utilized, although a behavioral prescription pad was used with 20% of overweight patients. Discussion: A modest investment in clinician and staff training designed to be feasible in a clinical setting was associated with substantial increases in the use of appropriate tools and practices for the assessment and management of pediatric overweight. Such training may help to augment and improve the processes of pediatric health care delivery for addressing overweight. The training provides a viable model for future CME efforts in other health care settings. [source] Extension of potential predictability of Indian summer monsoon dry and wet spells in recent decadesTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 648 2010J. M. Neena Abstract An understanding of the limit on potential predictability is crucial for developing appropriate tools for extended-range prediction of active/break spells of the Indian summer monsoon (ISM). The global low-frequency changes in climate modulate the annual cycle of the ISM and can influence the intrinsic predictability limit of the ISM intraseasonal oscillations (ISOs). Using 104-year (1901,2004) long daily rainfall data, the change in potential predictability of active and break spells are estimated by an empirical method. It is found that the potential predictability of both active and break spells have undergone a rapid increase during the recent three decades. The potential predictability of active spells has shown an increase from one week to two weeks while that for break spells increased from two weeks to three weeks. This result is interesting and intriguing in the backdrop of recent finding that the potential predictability of monsoon weather has decreased substantially over the same period compared to earlier decades due to increased potential instability of the atmosphere. The possible role of internal dynamics and external forcing in producing this change has been explored. The changes in energy exchange between the synoptic and ISO scale and the different ISO modes as evidenced by energetics computations in frequency domain also support the increased potential predictability of ISO. Our finding provides optimism for improved and useful extended-range prediction of monsoon active and break spells. Copyright © 2010 Royal Meteorological Society [source] | ||||||||||||||||||||||||||||