Home About us Contact
|
Home About us Contact | ||
|
|
||
Same Characteristics (same + characteristic)
Selected AbstractsSpatial point-process statistics: concepts and application to the analysis of lead contamination in urban soil,ENVIRONMETRICS, Issue 4 2005Christian Walter Abstract This article explores the use of spatial point-process analysis as an aid to describe topsoil lead distribution in urban environments. The data used were collected in Glebe, an inner suburb of Sydney. The approach focuses on the locations of punctual events defining a point pattern, which can be statistically described through local intensity estimates and between-point distance functions. F -, G - and K -surfaces of a marked spatial point pattern were described and used to estimate nearest distance functions over a sliding band of quantiles belonging to the marking variable. This provided a continuous view of the point pattern properties as a function of the marking variable. Several random fields were simulated by selecting points from random, clustered or regular point processes and diffusing them. Recognition of the underlying point process using variograms derived from dense sampling was difficult because, structurally, the variograms were very similar. Point-event distance functions were useful complimentary tools that, in most cases, enabled clear recognition of the clustered processes. Spatial sampling quantile point pattern analysis was defined and applied to the Glebe data set. The analysis showed that the highest lead concentrations were strongly clustered. The comparison of this data set with the simulation confidence limits of a Poisson process, a short-radius clustered point process and a geostatistical simulation showed a random process for the third quartile of lead concentrations but strong clustering for the data in the upper quartile. Thus the distribution of topsoil lead concentrations over Glebe may have resulted from several contamination processes, mainly from regular or random processes with large diffusion ranges and short-range clustered processes for the hot spots. Point patterns with the same characteristics as the Glebe experimental pattern could be generated by separate additive geostatistical simulation. Spatial sampling quantile point patterns statistics can, in an easy and accurate way, be used complementarily with geostatistical methods. Copyright © 2005 John Wiley & Sons, Ltd. [source] Estimation of net nitrogen flux between the atmosphere and a semi-natural grassland ecosystem in HungaryEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 5 2010A. Machon The aim of this work is to estimate the net N balance (deposition , emission) between the atmosphere and a semi-arid, semi-natural grassland (Bugac station, Central Hungary, CarboEurope IP, NitroEurope IP level 3 site). Dry deposition of N compounds has been determined by the inferential method, based on continuous monitoring of NO2 gas and daily 24-hour concentration measurements of HNO3 vapour, NH3 gas, and NH4+ and NO3, particles, using dry deposition velocities from the literature, measured above surfaces with the same characteristics as Bugac station. The bi-directional flux of NH3 within the atmosphere and the canopy (excluding soil emission) has also been estimated by the inferential method. Wet deposition of nitrate and ammonium ions was calculated on the basis of daily precipitation sampling and concentration measurements of nitrate and ammonium ions. To estimate the soil-atmosphere exchange of different gaseous N forms (N2, NO, N2O, NH3), the DNDC model was used as validated by the chamber measurements of NO and N2O soil emission fluxes. Soil emissions of NO and N2O have been determined by dynamic and static soil chamber methods, respectively. The measurement and modelling activity covers a complete year. Using the measured and modelled data, the calculated N balance at Bugac station between August 2006 and July 2007 is estimated at ,8.8 kg N ha,1 year,1 (deposition) as a sum of the deposition and emission terms (,10.4 and 1.6 kg N ha,1 year,1, respectively). Due to the warm and dry weather during the examined period, wet fluxes were substantially lower than usual, which may also have altered the regular yearly course of dry deposition and emission. [source] Price Performance Following Share-Repurchase Announcements by Closed-End FundsFINANCIAL REVIEW, Issue 4 2007Aigbe Akhigbe G14; G20; G23 Abstract We investigate the price performance of closed-end funds that announce share-repurchase programs. Closed-end funds experience positive average stock-price reactions to the announcements. The long-run buy-and-hold abnormal returns of repurchasing funds over the subsequent three years are significantly higher than a nonrepurchasing control sample matched by size, type, investment style and geographic diversification. Funds with larger discounts, international funds, equity funds, and funds that announce larger repurchases or frequently announce repurchases, experience more positive stock-price reactions. Except for larger repurchases, the same characteristics are associated with more positive long-run buy-and-hold returns. [source] A new approach to avoid excessive numerical diffusion in Eulerian,Lagrangian methodsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 11 2008A. Younes Abstract Lumping is often used to avoid non-physical oscillations for advection,dispersion equations but is known to add numerical diffusion. A new approach is detailed in order to avoid excessive numerical diffusion in Eulerian,Lagrangian methods when several time steps are used. The basic idea of this approach is to keep the same characteristics during all time steps and to interpolate only the concentration variations due to the dispersion process. In this way, numerical diffusion due to the lumping is removed at the end of each time step. The method is combined with the Eulerian,Lagrangian localized adjoint method (ELLAM) which is a mass conservative characteristic method for solving the advection,dispersion equation. Two test problems are modelled to compare the proposed method to the consistent, the full and the selective lumping approaches for linear and non-linear transport equations. Copyright © 2007 John Wiley & Sons, Ltd. [source] Utilisation de la méthode du cubic simplex pour l'optimisation de la formulation a froid d'une emulsion de thioglycolate de calciumINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 5 2003N. Moulai-Mostefa Synopsis The aim of this work relates to the optimization of a cold formulation of a depilatory emulsion containing thioglycolate of calcium, which presents the same characteristics as a reference product. To lead to this objective, a cubic simplex method was used. A preliminary formulation was preformed to evaluate the influence of each factor on the process formulation. The depilatory creams carried out present a rheological behaviour described by the model of Hershell,Bulkely, whose parameters are considered as responses of the optimizing system. This strategy allows both reducing and optimizing the number of experiments. The rheological measurements and the tests of stability showed that the use of an emulsifying polymer led to obtain a stable depilatory cream with a good effectiveness at a strong pH value. Résumé L'objectif principal de ce travail concerne l'optimisation de la formulation à froid d'une émulsion dépilatoire à base de thioglycolate de calcium, présentant les mêmes caractéristiques qu'un produit de référence. Pour aboutir à cet objectif, on a utilisé la méthode du cubic simplex. L'étude de préformulation a permis d'évaluer avec précision l'influence des différents facteurs sur le processus de formulation. Les crèmes dépilatoires réalisées présentent un comportement rhéologique décrit par le modèle de Hershell,Bulkley dont les deux paramètres sont considérés comme réponses du système à optimiser. Les plans d'expériences utilisés ont permis de restreindre le nombre d'essais à réaliser. Les résultats expérimentaux de l'analyse rhéologique et les tests de stabilité ont montré que l'utilisation d'un polymère émulsifiant conduit à l'obtention d'une crème dépilatoire stable possédant une bonne efficacité aux fortes valeurs du pH. [source] A temporary home to nurture health: lived experiences of older nursing home residents in TaiwanJOURNAL OF CLINICAL NURSING, Issue 14 2008Hsiu-Hsin Tsai PhD Aim., This study explored the lived experiences of older nursing home residents in Taiwan. Background., With more long-term care institutions in Taiwan, older people are more often placed in nursing homes than in the past. Increased understanding of their lived experience is essential to assess residents' needs and determine the effectiveness of nursing interventions. Design., A qualitative design was used to gain a deeper understanding of the lived experiences of older nursing home residents in Taiwan. Methods., Focus groups, followed by in-depth interviews, were used to gather information from 33 older residents at eight nursing homes in northern Taiwan. Participants were asked to describe what was important to them and what impressed them most in their daily lives in the nursing home. Participants (24 females and nine males) were on an average 75·3 years old. Verbatim transcripts of audiotaped focus groups and interviews were analysed by thematic analysis via ATLAS.ti software. Results., The core theme of older residents' nursing home experience was ,a temporary home to nurture health'. This core theme was reflected in participants' descriptions of their overall life in the nursing home as a temporary experience to nurture their health. Their everyday experience was characterised by four subthemes: highly structured lifestyle, restricted activities, safety concerns and social interactions. Relevance to clinical practice., Our findings may enhance policy makers' and healthcare providers' understanding of the lived experience of older nursing home residents, thus guiding the evaluation and development of nursing home services to improve residents' lives. For example, residents with the same characteristics could be placed in the same room or same floor, thus increasing their interactions with other residents. Residents' interactions with family members could also be developed using the Internet or mobile telephones. [source] Notes on quantitative structure-properties relationships (QSPR) (1): A discussion on a QSPR dimensionality paradox (QSPR DP) and its quantum resolutionJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 7 2009Ramon Carbó-Dorca Abstract Classical quantitative structure-properties relationship (QSPR) statistical techniques unavoidably present an inherent paradoxical computational context. They rely on the definition of a Gram matrix in descriptor spaces, which is used afterwards to reduce the original dimension via several possible kinds of algebraic manipulations. From there, effective models for the computation of unknown properties of known molecular structures are obtained. However, the reduced descriptor dimension causes linear dependence within the set of discrete vector molecular representations, leading to positive semi-definite Gram matrices in molecular spaces. To resolve this QSPR dimensionality paradox (QSPR DP) here is proposed to adopt as starting point the quantum QSPR (QQSPR) computational framework perspective, where density functions act as infinite dimensional descriptors. The fundamental QQSPR equation, deduced from employing quantum expectation value numerical evaluation, can be approximately solved in order to obtain models exempt of the QSPR DP. The substitution of the quantum similarity matrix by an empirical Gram matrix in molecular spaces, build up with the original non manipulated discrete molecular descriptor vectors, permits to obtain classical QSPR models with the same characteristics as in QQSPR, that is: possessing a certain degree of causality and explicitly independent of the descriptor dimension. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009 [source] Flexible system for simulating and tele-operating robots through the internetJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 3 2005F. A. Candelas Simulation and teleoperation tools offer many advantages for the training or learning of technological subjects, such as flexibility in time-tables and student access to expensive and limited equipment. In this paper, we present a new system for simulating and tele-operating robot arms through the Internet, which allows many users to simulate and test positioning commands for a robot by means of a virtual environment, as well as execute the validated commands in a real remote robot of the same characteristics. The main feature of the system is its flexibility in managing different robots or including new robot models and equipment. © 2005 Wiley Periodicals, Inc. [source] Motion analysis of stereotyped hand movements in Rett syndromeJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 2 2003M. Wright Abstract Background Rett syndrome is a genetic developmental disorder, and stereotyped hand movements are a striking feature of this condition. The aim of the present study was to subject these movements to objective analysis and compare the results in one girl at different ages. Method The hand movements of a 10-year-old girl with Rett syndrome were subjected to accurate, three-dimensional (3D) computerized motion analysis and compared to two-dimensional (2D) video analysis of the same girl at 3 years of age. Results Three-dimensional computerized analysis revealed regular patterns with strong coupling between the hands. Frequency analysis showed a dominant frequency at 1.2 Hz, with a higher component at 2.4 Hz that may relate to the activity of basic rhythm generators. The same coupling characteristics were extracted from standard, 2D video recordings made at the same time as the 3D capture. Conclusion An informal video of the same girl taken when she was 3 years of age was analysed in the same way as the 2D video and showed the same characteristics, indicating the possible future use of automated video analysis for early screening and intervention evaluation. [source] A Comparison of Correlates of DSM-IV Alcohol Abuse or Dependence Among More Than 400 Sons of Alcoholics and ControlsALCOHOLISM, Issue 1 2001M. A. Schuckit Background: Alcohol dependence and abuse are defined as separate disorders. However, relatively few data are available about whether the same characteristics predict both syndromes. Methods: Complete data were available from the 15 year follow-up of 411 men who originally had been evaluated from a university population at about age 20. Both baseline data gathered prospectively and the retrospective ratings in six domains of life functioning were analyzed for their relationship to the development of alcohol abuse or dependence during the follow-up. Results: Baseline characteristics of a family history of substance use disorders, the quantity and frequency of drinking, the history of alcohol-related problems, and the level of response to alcohol all predicted future alcohol abuse or dependence, but only an alcoholic second-degree relative or a first-degree drug-dependent family member differentially predicted dependence. Logistic regression analyses revealed that similar baseline characteristics combined to predict dependence and, separately, abuse. When the domains of functioning during the 15 years were included, positive alcohol expectancies, poor coping mechanisms, low level of social support, and drinking in the environment contributed to both dependence and abuse, although the relationship was stronger for dependence. Conclusions: The predictors and correlates of alcohol abuse and dependence in this group of men were similar. Further research in additional populations and on other drugs is needed to determine if the two syndromes overlap sufficiently to be combined. [source] Current opportunities and challenges in skeletal muscle tissue engineeringJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 6 2009Merel Koning Abstract The purpose of this article is to give a concise review of the current state of the art in tissue engineering (TE) of skeletal muscle and the opportunities and challenges for future clinical applicability. The endogenous progenitor cells of skeletal muscle, i.e. satellite cells, show a high proneness to muscular differentiation, in particular exhibiting the same characteristics and function as its donor muscle. This suggests that it is important to use an appropriate progenitor cell, especially in TE facial muscles, which have a exceptional anatomical and fibre composition compared to other skeletal muscle. Muscle TE requires an instructive scaffold for structural support and to regulate the proliferation and differentiation of muscle progenitor cells. Current literature suggests that optimal scaffolding could comprise of a fibrin gel and cultured monolayers of muscle satellite cells obtained through the cell sheet technique. Tissue-engineered muscle constructs require an adequate connection to the vascular system for efficient transport of oxygen, carbon dioxide, nutrients and waste products. Finally, functional and clinically applicable muscle constructs depend on adequate neuromuscular junctions with neural cells. To reach this, it seems important to apply optimal electrical, chemotropic and mechanical stimulation during engineering and discover other factors that influence its formation. Thus, in addition to approaches for myogenesis, we discuss the current status of strategies for angiogenesis and neurogenesis of TE muscle constructs and the significance for future clinical use. Copyright © 2009 John Wiley & Sons, Ltd. [source] Some biological characteristics of transferred free flapsMICROSURGERY, Issue 5 2007Jefta V. Kozarski M.D., Ph.D. At the Clinic for plastic surgery and burns of the MMA, we examined 33 patients with transferred 5 cutaneous, 18 miocutaneous, and 10 osteocutaneous free flaps out of which 10 were done on foot, 13 on the lower leg, and 10 on the face. We analyzed the blood circulation (patency of arterial microanastomosis and perfusion) of transferred free flaps, recovery of sensitivity, functioning of the sebaceous and sweat glands as well as histomorphologic changes in the skin of the transferred free flaps during the period of 6 up to 36 months after the free flap transfer and compared with the same characteristics of the skin and tissue of the surrounding area of the recipient region. © 2007 Wiley-Liss, Inc. Microsurgery, 2007. [source] hp -Adaptive Finite Element Methods for Variational InequalitiesPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2008Andreas SchröderArticle first published online: 25 FEB 200 In this work, we combine an hp,adaptive strategy with a posteriori error estimates for variational inequalities, which are given by contact problems. The a posteriori error estimates are obtained using a general approach based on the saddle point formulation of contact problems and making use of a yposteriori error estimates for variational equations. Error estimates are presented for obstacle problems and Signorini problems with friction. Numerical experiments confirm the reliability of the error estimates for finite elements of higher order. The use of the hp,adaptive strategy leads to meshes with the same characteristics as geometric meshes and to exponential convergence. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Pacing Rhythms of "Wanderers" with DementiaPSYCHOGERIATRICS, Issue 1 2001Koji Hori Background: As wandering in the demented is difficult to define qualitatively, we tride to define it quantitatively. We investigated the relationship between wandering and rhythm abnormalities. Methods: In order to study the pacing rhythms of wanderers observed in a subgroup of demented inpatients (dementia due to Alzheimer's disease and vascular dementia), we assessed 115 inpatients in terms of steps during four parts of a day and total daily steps using a pedometer. As the mean+2 S.D. of total daily steps in the nondemented was 9,979, we defined 10,000 steps in a day as the cut off for defining demented wanderers versus nonwanderers. Then, the pacing rhythms (nadir part and amplitude) were compared among demented wanderers, demented nonwanderers and nondemented subjects. Results: That there were no statistically significant differences among the three groups. But wandering groups defined by pedometer exhibited many of the same characteristics in wanderers observed in other studies. Conclusion: The quantification of steps might provide a good hallmark of wandering behaviors in the demented, and these results might indicate hyperpacing rather than rhythm dysfunctions to be essential to wandering behavior. [source] New milliliter-scale stirred tank bioreactors for the cultivation of mycelium forming microorganismsBIOTECHNOLOGY & BIOENGINEERING, Issue 3 2010Ralf Hortsch Abstract A novel milliliter-scale stirred tank bioreactor was developed for the cultivation of mycelium forming microorganisms on a 10 milliliter-scale. A newly designed one-sided paddle impeller is driven magnetically and rotates freely on an axis in an unbaffled reaction vessel made of polystyrene. A rotating lamella is formed which spreads out along the reactor wall. Thus an enhanced surface-to-volume ratio of the liquid phase is generated where oxygen is introduced via surface aeration. Volumetric oxygen transfer coefficients (kLa),>,0.15,s,1 were measured. The fast moving liquid lamella efficiently prevents wall growth and foaming. Mean power consumption and maximum local energy dissipation were measured as function of operating conditions in the milliliter-scale stirred tank bioreactor (V,=,10,mL) and compared to a standard laboratory-scale stirred tank bioreactor with six-bladed Rushton turbines (V,=,2,000,mL). Mean power consumption increases with increasing impeller speed and shows the same characteristics and values on both scales. The maximum local energy dissipation of the milliliter-scale stirred tank bioreactor was reduced compared to the laboratory-scale at the same mean volumetric power input. Hence the milliliter impeller distributes power more uniformly in the reaction medium. Based on these data a reliable and robust scale-up of fermentation processes is possible. This was demonstrated with the cultivation of the actinomycete Streptomyces tendae on both scales. It was shown that the process performances were equivalent with regard to biomass concentration, mannitol consumption and production of the pharmaceutical relevant fungicide nikkomycin Z up to a process time of 120,h. A high parallel reproducibility was observed on the milliliter-scale (standard deviation,<,8%) with up to 48 stirred tank bioreactors operated in a magnetic inductive drive. Rheological behavior of the culture broth was measured and showed a highly viscous shear-thinning non-Newtonian behavior. The newly developed one-sided paddle impellers operated in unbaffled reactors on a 10 milliliter-scale with a magnetic inductive drive for up to 48 parallel bioreactors allows for the first time the parallel bioprocess development with mycelium forming microorganisms. This is especially important since these kinds of cultivations normally exhibit process times of 100,h and more. Thus the operation of parallel stirred tank reactors will have the potential to reduce process development times drastically. Biotechnol. Bioeng. 2010; 106: 443,451. © 2010 Wiley Periodicals, Inc. [source] The Role of Indigenous Peoples in Guatemalan Political Advertisements: An Ethnographic Content AnalysisCOMMUNICATION, CULTURE & CRITIQUE, Issue 3 2010Colleen Connolly-Ahern This study investigates the current status of indigenous peoples within Guatemalan society, as articulated in one of the most relevant forms of modern communication, political advertising, and defined by one of the most relevant forms of self-expression to the indigenous peoples of Guatemala, the traje. Using ethnographic content analysis, the study examines the roles and characterizations of indigenous people in 67 television commercials from across the Guatemalan political spectrum. Results indicate that indigenous people are most often seen as "crowd members," and are never given important roles, such as "candidate endorser" or "undecided voter." Overall, wearing traje is associated with helplessness and separateness. The commercials of Q'iché Maya candidate Rigoberta Menchú exhibited many of the same characteristics of other candidates. Le rôle des peuples autochtones dans les publicités politiques guatémaltèques : une analyse de contenu ethnographique Colleen Connolly-Ahern & Antoni Castells i Talens Cette étude explore le statut actuel des peuples autochtones dans la société guatémaltèque, telle qu'elle est articulée dans l'une des formes les plus appropriées de communication moderne, les publicités politiques, et telle que définie par l'une des formes d'expression des peuples autochtones du Guatemala les plus pertinentes, le «traje». Par une analyse de contenu ethnographique, l'étude explore les rôles et les représentations des peuples autochtones dans 67 publicités télévisées couvrant le spectre politique du Guatemala. Les résultats indiquent que les peuples autochtones sont le plus souvent vus comme des «membres de la foule». Ils n'ont jamais de rôles importants comme celui de «partisan d'un candidat» ou d'«électeur indécis'. Dans l'ensemble, le port du «traje» est associéà l'impuissance et à la différence. Les publicités de la candidate maya k'iche' Rigoberta Menchú présentaient plusieurs des mêmes caractéristiques que celles des autres candidats. El Rol de las Personas Indígenas en la Publicidad Política de Guatemala: Un Análisis de Contenido Etnográfico Colleen Connolly-Ahern & Antoni Castells i Talens Advertising and Public Relations College of Communications, Penn State University, State College, PA 16802, USA Resumen Este estudio investiga el estado corriente de las personas indígenas dentro de la sociedad Guatemalteca, articulado en una de las formas más relevantes de la comunicación moderna, la publicidad política, y definido por una de las formas más relevantes de auto expresión de las personas Indígenas de Guatemala, el traje. Usando un análisis de contenido etnográfico, este estudio examina los roles y las caracterizaciones de las personas indígenas en 67 comerciales de televisión a través del espectro político Guatemalteco. Los resultados indican que las personas indígenas son vistas más a menudo como "miembros de la multitud'' y nunca se les da roles importantes tales como ,,el candidato de la representación'' o ,,el votante indeciso. '' En general, el uso del traje está asociado con la impotencia y la separación. Los comerciales de la candidata Q'ich,e Maya Rigoberta Menchú exhibieron muchas de las mismas características de los otros candidatos. [source] | |||||||||||||