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Distance
Kinds of Distance Terms modified by Distance Selected AbstractsISOLATION BY DISTANCE IN EQUILIBRIUM AND NONEQUILIBRIUM POPULATIONS OF FOUR TALITRID SPECIES IN THE MEDITERRANEAN SEAEVOLUTION, Issue 5 2000Elvira De Matthaeis Abstract Allozymic variation at 21,23 loci was studied in 28 populations of Talitrus saltator, 23 populations of Orchestia montagui, 13 populations of O. stephenseni, and five populations of Platorchestia platensis from the Mediterranean Basin. Different levels of gene flow (Nm,) were detected within each species at the scale of the whole Mediterranean: O. montagui and P. platensis had low population structure, with levels of Nm, 1, whereas the T. saltator and O. stephenseni populations have values of Nm, < 1. The relationship between Nm, and geographic distance was analyzed to test for the presence of an isolation by distance pattern in the spatial genetic variation within each species. A model of isolation by distance is useful to describe the pattern of genetic structuring of study species at the scale of the whole Mediterranean: geographic distance explained from 28% to 70% of the variation in gene flow. In the Aegean area all species showed an island model of genetic structuring regardless of the levels of gene flow. [source] Ethnic differences in anemia among patients with diabetes mellitus: The Diabetes Study of Northern California (DISTANCE),AMERICAN JOURNAL OF HEMATOLOGY, Issue 1 2010Ameena T. Ahmed To examine ethnic differences in hemoglobin testing practices and to test the hypothesis that ethnicity is an independent predictor of anemia among patients with diabetes mellitus. We conducted a panel study to assess the rate of hemoglobin testing during 1999,2001 and the period prevalence and incidence of anemia among 79,985 adults with diabetes mellitus receiving care within Kaiser Permanente of Northern California. Anemia was defined as hemoglobin <13.0 g/dL in men or < 12.0 g/dL in women. Overall, 82.1% of the cohort was tested for anemia at least once during the 3-year study period. Mixed ethnicity patients were most likely to be tested, followed by whites, blacks, Latinos, and Asians (P < 0.0001). Fifteen percent of the cohort had prevalent anemia at baseline, and an additional 22% of those tested developed anemia during the study period. Anemia was more prevalent among blacks and mixed ethnicity persons compared with other racial/ethnic groups. Anemia was also more prevalent among those ,70 years of age or with estimated glomerular filtration rate <60 ml/min/1.73 m2. In multivariable models, blacks had higher and Asians had lower odds of prevalent anemia and hazard ratios of incident anemia compared with whites. Within a large, diverse cohort with diabetes, ethnicity was predictive of anemia, even after adjustment for age, level of kidney function, and other potential confounders. Blacks with diabetes are at increased risk of anemia relative to whites. These differences may account for some of the observed ethnic disparities in diabetes complications. Am. J. Hematol., 2010. © 2009 Wiley-Liss, Inc. [source] DISTANCE, BANK HETEROGENEITY AND ENTRY IN LOCAL BANKING MARKETS,THE JOURNAL OF INDUSTRIAL ECONOMICS, Issue 3 2008ROBERTO FELICI We examine the determinants of entry into Italian local banking markets during the period 1991,2002 and build a simple model in which the probability of branching in a new market depends on the features of both the local market and the potential entrant. Econometric findings show that banks are more likely to expand into those markets that are closest to their pre-entry locations. Large banks are also more able to cope with distance-related entry costs than small banks. Finally, banks have become increasingly able to open branches in distant markets, due to the advent of information and communication technologies. [source] LIVING A DISTRIBUTED LIFE: MULTILOCALITY AND WORKING AT A DISTANCEANNALS OF ANTHROPOLOGICAL PRACTICE, Issue 1 2008Brigitte Jordan In the last few years, new collaboration and communication technologies have led to a deterritorialization of work, allowing for the rise of new work- and lifestyles. In this article, I use my own transition from the life of a corporate researcher to that of a multilocal mobile consultant for tracking some of the patterns I see in a changing cultural and economic environment where work and workers are no longer tied to a specific place of work. My main interest lies in identifying some of the behavioral shifts that are happening as people are caught up in and attempt to deal with this changing cultural landscape. Writing as a knowledge worker who now moves regularly from a work,home place in the Silicon Valley of California to another in the tropical lowlands of Costa Rica, I use my personal transition as a lens through which to trace new, emergent patterns of behavior, of values, and of social conventions. I assess the stresses and joys, the upsides and downsides, the challenges and rewards of this work- and lifestyle and identify strategies for making such a life successful and rewarding. Throughout, there emerges an awareness of the ways in which the personal patterns described reflect wider trends and cumulatively illustrate global transformation of workscapes and lifescapes. These types of local patterns in fact constitute the on-the-ground material reality of global processes that initiate and sustain widespread culture change and emergent societal transformations. [source] Perceptual 3D pose distance estimation by boosting relational geometric featuresCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 2-3 2009Cheng Chen Abstract Traditional pose similarity functions based on joint coordinates or rotations often do not conform to human perception. We propose a new perceptual pose distance: Relational Geometric Distance that accumulates the differences over a set of features that reflects the geometric relations between different body parts. An extensive relational geometric feature pool that contains a large number of potential features is defined, and the features effective for pose similarity estimation are selected using a set of labeled data by Adaboost. The extensive feature pool guarantees that a wide diversity of features is considered, and the boosting ensures that the selected features are optimized when used jointly. Finally, the selected features form a pose distance function that can be used for novel poses. Experiments show that our method outperforms others in emulating human perception in pose similarity. Our method can also adapt to specific motion types and capture the features that are important for pose similarity of a certain motion type. Copyright © 2009 John Wiley & Sons, Ltd. [source] Möbius Transformations For Global Intrinsic Symmetry AnalysisCOMPUTER GRAPHICS FORUM, Issue 5 2010Vladimir G. Kim The goal of our work is to develop an algorithm for automatic and robust detection of global intrinsic symmetries in 3D surface meshes. Our approach is based on two core observations. First, symmetry invariant point sets can be detected robustly using critical points of the Average Geodesic Distance (AGD) function. Second, intrinsic symmetries are self-isometries of surfaces and as such are contained in the low dimensional group of Möbius transformations. Based on these observations, we propose an algorithm that: 1) generates a set of symmetric points by detecting critical points of the AGD function, 2) enumerates small subsets of those feature points to generate candidate Möbius transformations, and 3) selects among those candidate Möbius transformations the one(s) that best map the surface onto itself. The main advantages of this algorithm stem from the stability of the AGD in predicting potential symmetric point features and the low dimensionality of the Möbius group for enumerating potential self-mappings. During experiments with a benchmark set of meshes augmented with human-specified symmetric correspondences, we find that the algorithm is able to find intrinsic symmetries for a wide variety of object types with moderate deviations from perfect symmetry. [source] Interactive Graphics for Computer Adaptive TestingCOMPUTER GRAPHICS FORUM, Issue 8 2009I. Cheng K.3.1 [Computer Milieux]: Computer and Education , Computer Uses in Education; I.3.8 [Computing Methodologies]: Computer Graphics , Application Abstract Interactive graphics are commonly used in games and have been shown to be successful in attracting the general audience. Instead of computer games, animations, cartoons, and videos being used only for entertainment, there is now an interest in using interactive graphics for ,innovative testing'. Rather than traditional pen-and-paper tests, audio, video and graphics are being conceived as alternative means for more effective testing in the future. In this paper, we review some examples of graphics item types for testing. As well, we outline how games can be used to interactively test concepts; discuss designing chemistry item types with interactive 3D graphics; suggest approaches for automatically adjusting difficulty level in interactive graphics based questions; and propose strategies for giving partial marks for incorrect answers. We study how to test different cognitive skills, such as music, using multimedia interfaces; and also evaluate the effectiveness of our model. Methods for estimating difficulty level of a mathematical item type using Item Response Theory (IRT) and a molecule construction item type using Graph Edit Distance are discussed. Evaluation of the graphics item types through extensive testing on some students is described. We also outline the application of using interactive graphics over cell phones. All of the graphics item types used in this paper are developed by members of our research group. [source] Effect of Graft Size, Angle, and Intergraft Distance on Dense Packing in Hair TransplantDERMATOLOGIC SURGERY, Issue 6 2005Mohammed Alhaddab MD Background. The maximum number of hair grafts that can be safely implanted in 1 cm2 is still debatable. To our knowledge, no previous report has addressed this issue in three dimensions, taking into account the size, the angle of the graft, and the intergraft distance. Objectives. To study the effect of the size and angle of the graft and the intergraft distance on dense packing. Methods. Using a mathematical formula (the maximum number of hair grafts in 1 cm2 = 33 * cosine), the volume of the recipient area and the volume of the hair graft are calculated, assuming that the surface area of the recipient area is 1 cm2, the diameter of the hair graft is 1 mm, and the intergraft distance is 1.5 mm laterally and 1 mm anteriorly and posteriorly. Results. The maximum number of hair grafts that could be implanted in 1 cm2 at a 90 angle in relation to the skin surface is 33 grafts, at a 60 angle is 28 grafts, and at a 30 angle is 16 grafts. Conclusion. The maximum number of hair grafts that can be implanted in any given recipient area depends on the graft size, the angle or direction of these grafts, and the intergraft distance. Where more space is allowed between the grafts, and the more acute the angle, the fewer hair grafts that can be implanted. [source] Phytogeographical evidence for post-glacial dispersal limitation of European beech forest speciesECOGRAPHY, Issue 6 2009Wolfgang Willner The post-glacial migration of European beech Fagus sylvatica has been addressed by many studies using either genetic or fossil data or a combination of both. In contrast to this, only little is known about the migration history of beech forest understorey species. In a review of phytosociological literature, we identified 110 plant species which are closely associated with beech forest. We divided the distribution range of European beech forests into 40 geographical regions, and the presence or absence of each species was recorded for each region. We compared overall species numbers per region and numbers of narrow-range species (species present in <10 regions). A multiple regression model was used to test for the explanatory value of three potential diversity controls: range in elevation, soil type diversity, and distance to the nearest potential refuge area. A hierarchical cluster analysis of the narrow-range species was performed. The frequency of range sizes shows a U-shaped distribution, with 42 species occurring in <10 regions. The highest number of beech forest species is found in the southern Alps and adjacent regions, and species numbers decrease with increasing distance from these regions. With only narrow-range species taken into consideration, secondary maxima are found in Spain, the southern Apennines, the Carpathians, and Greece. Distance to the nearest potential refuge area is the strongest predictor of beech forest species richness, while altitudinal range and soil type diversity had little or no predictive value. The clusters of narrow-range species are in good concordance with the glacial refuge areas of beech and other temperate tree species as estimated in recent studies. These findings support the hypothesis that the distribution of many beech forest species is limited by post-glacial dispersal rather than by their environmental requirements. [source] Spatial utilisation of fast-ice by Weddell seals Leptonychotes weddelli during winterECOGRAPHY, Issue 3 2005Samantha Lake This study describes the distribution of Weddell seals Leptonychotes weddelli in winter (May,September 1999) at the Vestfold Hills, in Prydz Bay, East Antarctica. Specifically, we describe the spatial extent of haul-out sites in shore,fast sea-ice, commonly referred to as fast-ice. As winter progressed, and the fast-ice grew thick (ca 2 m), most of the inshore holes closed over, and the seals' distribution became restricted to ocean areas beyond land and islands. Using observations from the end of winter only, we fitted Generalised Additive Models (GAMs) to generate resource selection functions, which are models that yield values proportional to the probability of use. The models showed that seal distribution was defined mainly by distance to ice-edge and distance to land. Distance to ice-bergs was also selected for models of some regions. We present the results as maps of the fitted probability of seal presence, predicted by the binomial GAM for offshore regions, both with and without autocorrelation terms. The maps illustrate the expected distribution encompassing most of the observed distribution. On this basis, we hypothesise that propensity for the fast-ice to crack is the major determinant of Weddell seal distribution in winter. Proximity to open water and pack-ice habitats could also influence the distribution of haul-out sites in fast-ice areas. This is the first quantitative study of Weddell seal distribution in winter. Potential for regional variation is discussed. [source] Spatial patterns, temporal variability, and the role of multi-nest colonies in a monogynous Spanish desert antECOLOGICAL ENTOMOLOGY, Issue 1 2002Xim Cerdá Abstract 1.,The colonies of the Spanish desert ant Cataglyphis iberica are polydomous. This study describes the temporal and spatial patterns of the polydomy in this species at two different sites, and presents analyses of its role in reducing the attacks of the queen over sexual brood, and in allowing better habitat exploitation. 2. The spatial distribution of nests was clumped while colonies were distributed randomly. Mean nearest neighbour distance ranged from 3.4 to 7.0 m for nests and from 12.3 to 14.1 m for colonies. Distance of foragers searching for food varied among nests: mean values were between 6.1 and 12.6 m. 3. At both sites, the maximum number of nests per colony occurred in summer, during the maximum activity period of the species. Colonies regrouped at the end of this period but overwintered in several nests. 4. Nest renewal in C. iberica colonies was high and showed great temporal variability: nests changed (open, close, re-open) continuously through the activity season and/or among years. The lifetime of up to 55% of nests was only 1,3 months. 5. Polydomy in C. iberica might decrease the interactions between the queen and the sexual brood. In all colonies excavated just before the mating period, the nest containing the queen did not contain any virgin female. Females were in the queenless nests of the colony. 6. The results also suggest that polydomous C. iberica colonies may enhance habitat exploitation because foraging activity per colony increases with nest number. The relationship between total prey input and foraging efficiency and number of nests per colony attains a plateau or even decreases after a certain colony size (four to six nests). This value agrees with the observed mean number of nests per colony in C. iberica. [source] Determination of iodide in samples with complex matrices by hyphenation of capillary isotachophoresis and zone electrophoresisELECTROPHORESIS, Issue 20 2007Pavla Pant Abstract A method has been developed for the determination of iodide in mineral water, seawater, cooking salt, serum, and urine based on hyphenation of capillary ITP and zone electrophoresis. A commercially available instrumentation for capillary ITP with column-switching system was used. ITP served for removal of chloride present in the analyzed samples in a ratio of 106,107:1 to iodide, zone electrophoresis was used for evaluation. Isotachophoretic separation proceeded in a capillary made of fluorinated ethylene,propylene copolymer of 0.8,mm id and 90,mm total length to the bifurcation point filled with a leading electrolyte (LE) composed of 8,mM HCl,+,16,mM ,-alanine (,-Ala),+,10% PVP,+,2.86,mM N2H4×2HCl, pH,3.2; and a terminating electrolyte composed of 8,mM H3PO4,+,16,mM ,-Ala,+,10% PVP,+,5,mM N2H4, pH,3.85 for all the matrices except seawater. For ITP of seawater the LE consisted of 50,mM HCl,+,100,mM ,-Ala,+,10% PVP +,2.86,mM N2H4×2HCl, pH,3.52. Distance of conductivity detector from the injection point and bifurcation point was 52 and 38,mm, respectively. Zone electrophoresis was performed in a capillary made of fused silica of 0.3,mm id and 160,mm total length filled with LE from isotachophoretic step. LODs reached for all matrices were 2,3×10,8,M concentration (2.5,4,,g/L) enabled monitoring of iodide in all analyzed samples with RSD 0.4,9.3%. Estimated concentrations of iodide in individual matrices were 10,6,10,8,M. [source] Effects of Pair-Bond and Social Context on Male,Female Interactions in Captive Titi Monkeys (Callicebus moloch, Primates: Cebidae)ETHOLOGY, Issue 12 2000Eduardo Fernandez-Duque In monogamous species, an abiding relationship between a specific adult male and a specific adult female is a defining feature of the social system. The interactions between these individuals are influenced by many factors, including not only the history of their relationship (for example, development of a mutual bond), but also the immediate effects of the prevailing social context (for example, presence and sex of extra-pair conspecifics). In this study we examined the effects of an existing bond and of social context on interactions between adult heterosexual pairs of the monogamous titi monkeys (Callicebus moloch). Twelve adult males and 12 adult females were tested with their cagemates and with an unfamiliar partner of the opposite sex in five social contexts: (1) mated male,female pair; (2) unfamiliar pair; (3) single female; (4) single male; and (5) empty stimulus cage. Results show that mated pairs were more affiliative than unfamiliar pairs and differentiated social contexts more sharply. Males were more responsive to context than females. Distance between mates was less and physical contact was more frequent in the presence of male,female pairs or a single male, than in the presence of a single female or an empty cage. These findings suggest that the presence and sex of strangers have a stronger influence on male,female interactions when the pair has an existing relationship. [source] Order Distance in Regular Point PatternsGEOGRAPHICAL ANALYSIS, Issue 3 2009Masashi Miyagawa This article examines the kth nearest neighbor distance for three regular point patterns: square, triangular, and hexagonal lattices. The probability density functions of the kth nearest distance and the average kth nearest distances are theoretically derived for k=1, 2, ,, 7. As an application of the kth nearest distance, we consider a facility location problem with closing of facilities. The problem is to find the optimal regular pattern that minimizes the average distance to the nearest open facility. Assuming that facilities are closed independently and at random, we show that the triangular lattice is optimal if at least 68% of facilities are open by comparing the upper and lower bounds of the average distances. El siguiente artículo examina la distancia de los k-vecinos más cercanos en látices cuadrados, triangulares y hexagonales. La funciones de densidad de probabilidad para las distancias k-más próximas y para las k-promedio más próximas son derivadas teóricamente para k=1,2,,7. Con el fin de demostrar una aplicación de la distancia k-más próxima los autores utilizan un ejemplo de localización y clausura de instalaciones. El objetivo es identificar el patrón regular óptimo que minimice la distancia promedio a la instalación abierta más cercana. Bajo el supuesto que las instalaciones cierran independientemente y aleatoriamente, y comparando los límites extremos superiores e inferiores de las distancias promedio, los autores demuestran que el patrón triangular es el óptimo si es que por lo menos 68 por ciento de las instalaciones permanecen abiertas. [source] Distance separated simultaneous sweeping, for fast, clean, vibroseis acquisitionGEOPHYSICAL PROSPECTING, Issue 1 2010Jack Bouska ABSTRACT Distance separated simultaneous sweeping DS3 is a new vibroseis technique that produces independent records, uncontaminated by simultaneous source interference, for a range of offsets and depths that span all target zones of interest. Use of DS3 on a recent seismic survey in Oman, resulted in a peak acquisition rate of 1024 records per hour. This survey employed 15 vibrators, with a distance separation of 12 km between simultaneous active sources, recorded by 8000 active channels across 22 live lines in an 18.5 km × 11 km receiver patch. Broad distribution of simultaneous sources, across an adequately sized recording patch, effectively partitions the sensors so that each trace records only one of the simultaneous sources. With proper source separation, on a scale similar to twice the maximum usable source receiver offset, wavefield overlap occurs below the zone of interest. This yields records that are indistinguishable from non-simultaneous source data, within temporal and spatial limits. This DS3 technique may be implemented using a wide variety of acquisition geometries, optimally with spatially large recording patches that enable appropriate source separation distances. DS3 improves acquisition efficiency without data quality degradation, eliminating the requirement for special data processing or noise attenuation. [source] Does size matter for dispersal distance?GLOBAL ECOLOGY, Issue 4 2007David G. Jenkins ABSTRACT Aim, The aim of this study is to answer the questions: (1) do small organisms disperse farther than large, or vice versa; and (2) does the observed pattern differ for passive and active dispersers? These questions are central to several themes in biogeography (including microbial biogeography), macroecology, metacommunity ecology and conservation biology. Location, The meta-analysis was conducted using published data collected worldwide. Methods, We collected and analysed 795 data values in the peer-reviewed literature for direct observations of both maximal dispersal distance and mass of the dispersing organisms (e.g. seeds, not trees). Analysed taxa ranged in size from bacteria to whales. We applied macroecology analyses based on null models (using Monte Carlo randomizations) to test patterns relative to specific hypotheses. Results, Collected dispersal distance and mass data spanned 9 and 21 orders of magnitude, respectively. Active dispersers dispersed significantly farther (P < 0.001) and were significantly greater in mass (P < 0.001) than passive dispersers. Overall, size matters: larger active dispersers attained greater maximum observed dispersal distances than smaller active dispersers. In contrast, passive-disperser distances were random with respect to propagule mass, but not uniformly random, in part due to sparse data available for tiny propagules. Conclusions, Size is important to maximal dispersal distance for active dispersers, but not for passive dispersers. Claims that microbes disperse widely cannot be tested by current data based on direct observations of dispersal: indirect approaches will need to be applied. Distance,mass relationships should contribute to a resolution of neutral and niche-based metacommunity theories by helping scale expectations for dispersal limitation. Also, distance,mass relationships should inform analyses of latitudinal species richness and conservation biology topics such as fragmentation, umbrella species and taxonomic homogenization. [source] The Demise of Distance?GROWTH AND CHANGE, Issue 1 2006The Declining Role of Physical Proximity for Knowledge Transmission ABSTRACT The transmission of knowledge diminishes with physical distance, one factor explaining the geographic clustering of scientific and industrial activity. The authors investigate how those distances have stretched over time,between collaborating inventors, and between inventors and the technology that inspires them. While physical distance is still a factor, it is clear that its constraining effects have weakened, especially for particular types of innovators, technologies, and regions of the United States. [source] Maternal distancing and event memory at 20 monthsINFANT AND CHILD DEVELOPMENT, Issue 4 2003Nathalie Prudhomme Abstract Maternal distancing strategies (Sigel, 1993 in The Development and Meaning of Psychological Distance, Cocking R, Renninger KA (eds). Erlbaum: Hillsdale, NJ; 141,158) with 20-month-olds were analysed during a mother,child interaction in a free play situation. Then, they were related to memory performance of the children as assessed by the elicited imitation paradigm with 4 three-step sequences of actions (Bauer, Hertsgaard, Child Dev. 1993; 64:1204). The aim of this work was to (1) confirm that the Sigel's model of distancing could be used with very young children under two; (2) study relationships between maternal distancing that stimulate representational competence of the child and memory performance of the children. Results showed two different patterns of correlations depending on the sequence type: for enabling sequences, significant positive correlations were obtained for the first two distancing levels whereas for arbitrary sequences no correlation was found whatever the distancing level. As discussed, the first pattern brings new arguments in support of declarative memory before the age of 2 years and reframes the memory development in a Vygotskyian interactionist perspective. The second pattern of correlations calls for replication and more investigation about the processes implied in memory of very young children for different sequence types. Copyright © 2003 John Wiley & Sons, Ltd. [source] Global potential distribution of an invasive species, the yellow crazy ant (Anoplolepis gracilipes) under climate changeINTEGRATIVE ZOOLOGY (ELECTRONIC), Issue 3 2008Youhua CHEN Abstract Changes to the Earth's climate may affect the distribution of countless species. Understanding the potential distribution of known invasive species under an altered climate is vital to predicting impacts and developing management policy. The present study employs ecological niche modeling to construct the global potential distribution range of the yellow crazy ant (Anoplolepis gracilipes) using past, current and future climate scenarios. Three modeling algorithms, GARP, BioClim and Environmental Distance, were used in a comparative analysis. Output from the models suggest firstly that this insect originated from south Asia, expanded into Europe and then into Afrotropical regions, after which it formed its current distribution. Second, the invasive risk of A. gracilipes under future climatic change scenarios will become greater because of an extension of suitable environmental conditions in higher latitudes. Third, when compared to the GARP model, BioClim and Environmental Distance models were better at modeling a species' ancestral distribution. These findings are discussed in light of the predictive accuracy of these models. [source] Distance from file tip to the major apical foramen in relation to the numeric meter reading on the display of three different electronic apex locatorsINTERNATIONAL ENDODONTIC JOURNAL, Issue 12 2009R. A. Higa Abstract Aim, To establish and compare the relationship between the distance from the file tip to the apical foramen and the numeric meter reading on the display of three different electronic apex locators (EALs). Methodology, A total of 12 extracted intact, straight, single-rooted human teeth with complete roots were used. The actual root canal length (AL) was determined after access preparation. For the electronic measurements with each EAL, silicon stops were fixed with auto-polymerizing resin to size 15 K-files at AL and 0.5, 1, 2, 3, 4 mm short of AL. The data was analysed by two-way anova and Tukey's honestly significant difference (HSD) test for multiple comparisons amongst EALs. Additionally, one-way anova and Tukey's HSD test were carried out for multiple comparisons amongst the measurements of each EAL. Results, There was a statistically significant difference amongst all EALs in indicating the position of file tips in relation to the major foramen (P < 0.05). The correlation between the meter reading and the position of the file tip from the apical foramen was statistically significant in the three EALs. There were significant differences amongst the measurements at distances from 0 to 2 mm in Justy III. In Dentaport, significant differences were found from 0 to 1 mm. However, the E-Magic Finder showed significant differences from 0 to 0.5 mm. Conclusions, Justy III was more capable of displaying the intracanal position of the file tip from the major foramen in mm whilst advancing through the root canal during electronic measurements than the Dentaport and E-Magic Finder Deluxe. [source] Face recognition based on face-specific subspaceINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 1 2003Shiguang Shan Abstract In this article, we present an individual appearance model based method, named face-specific subspace (FSS), for recognizing human faces under variation in lighting, expression, and viewpoint. This method derives from the traditional Eigenface but differs from it in essence. In Eigenface, each face image is represented as a point in a low-dimensional face subspace shared by all faces; however, the experiments conducted show one of the demerits of such a strategy: it fails to accurately represent the most discriminanting features of a specific face. Therefore, we propose to model each face with one individual face subspace, named Face-Specific Subspace. Distance from the face-specific subspace, that is, the reconstruction error, is then exploited as the similarity measurement for identification. Furthermore, to enable the proposed approach to solve the single example problem, a technique to derive multisamples from one single example is further developed. Extensive experiments on several academic databases show that our method significantly outperforms Eigenface and template matching, which intensively indicates its robustness under variation in illumination, expression, and viewpoint. © 2003 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13: 23,32, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10047 [source] The Effect of Linguistic Distance and Country of Origin on Immigrant Language Skills: Application to IsraelINTERNATIONAL MIGRATION, Issue 3 2001Michael Beenstock This article is concerned with identifying, for the first time, the separate effects of linguistic distance (language of origin) and country of origin on the destination language proficiency of immigrants. The determinants of Hebrew language proficiency (fluency and literacy) among immigrants in Israel are studied using the 1972 Census of Israel and the Immigration Absorption (panel) Surveys conducted in the 1970s. Country of origin and language of origin matter for proficiency in Hebrew, especially in the longer term. By country of origin, those from North Africa are the least proficient. By language of origin, Arabic speakers are the most proficient, suggesting a small linguistic distance from Hebrew. Immigrants from English-speaking origins are the least proficient in Hebrew. This may reflect a large linguistic distance or, more likely, the unique role of English as the international language, which reduces incentives for investments in Hebrew. Immigrants from dual-language countries of origin are more proficient in Hebrew than those from single language origins. [source] Prediction of Cardiorespiratory Fitness in Older Men Infected with the Human Immunodeficiency Virus: Clinical Factors and Value of the Six-Minute Walk DistanceJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 11 2009Krisann K. Oursler MD OBJECTIVES: To investigate factors related to cardiorespiratory fitness in older human immunodeficiency virus (HIV)-infected patients and to explore the utility of 6-minute walk distance (6-MWD) in measuring fitness. DESIGN: Cross-sectional study in clinic-based cohort. SETTING: Veterans Affairs Medical Center, Baltimore, Maryland. PARTICIPANTS: Forty-three HIV-infected men, median age 57 (range 50,82), without recent acquired immunodeficiency syndrome,related illness and receiving antiretroviral (ARV) therapy. MEASUREMENTS: Peak oxygen utilization (VO2peak) according to treadmill graded exercise testing, 6-MWD, grip strength, quadriceps maximum voluntary isometric contraction, cross-sectional area, muscle quality, and muscle adiposity. RESULTS: There was a moderate correlation between VO2peak (mean ± SD; 18.4 ± 5.6 mL/kg per minute) and 6-MWD (514 ± 91 m) (r=0.60, P<.001). VO2peak was lower in subjects with hypertension (16%, P<.01) and moderate anemia (hemoglobin 10,13 gm/dL; 15%, P=.09) than in subjects without these conditions. CD4 cell count (median 356 cells/mL, range 20,1,401) and HIV-1 viral load (84% nondetectable) were not related to VO2peak. Among muscle parameters, only grip strength was an independent predictor of VO2peak. Estimation of VO2peak using linear regression, including age, 6-MWD, grip strength, and hypertension as independent variables, explained 61% of the variance in VO2peak. CONCLUSION: Non-AIDS-related comorbidity predicts cardiorespiratory fitness in older HIV-infected men receiving ARV therapy. The 6-MWD is a valuable measure of fitness in this patient population, but a larger study with diverse subjects is needed. [source] Biogeography of Iberian freshwater fishes revisited: the roles of historical versus contemporary constraintsJOURNAL OF BIOGEOGRAPHY, Issue 11 2009Ana F. Filipe Abstract Aim, The question of how much of the shared geographical distribution of biota is due to environmental vs. historical constraints remains unanswered. The aim of this paper is to disentangle the contribution of historical vs. contemporary factors to the distribution of freshwater fish species. In addition, it illustrates how quantifying the contribution of each type of factor improves the classification of biogeographical provinces. Location, Iberian Peninsula, south-western Europe (c. 581,000 km2). Methods, We used the most comprehensive data on native fish distributions for the Iberian Peninsula, compiled from Portuguese and Spanish sources on a 20-km grid-cell resolution. Overall, 58 species were analysed after being categorized into three groups according to their ability to disperse through saltwater: (1) species strictly intolerant of saltwater (primary species); (2) species partially tolerant of saltwater, making limited incursions into saltwaters (secondary species); and (3) saltwater-tolerant species that migrate back and forth from sea to freshwaters or have invaded freshwaters recently (peripheral species). Distance-based multivariate analyses were used to test the role of historical (basin formation) vs. contemporary environmental (climate) conditions in explaining current patterns of native fish assemblage composition. Cluster analyses were performed to explore species co-occurrence patterns and redefine biogeographical provinces based on the distributions of fishes. Results, River basin boundaries were better at segregating species composition for all species groups than contemporary climate variables. This historical signal was especially evident for primary and secondary freshwater fishes. Eleven biogeographical provinces were delineated. Basins flowing to the Atlantic Ocean north of the Tagus Basin and those flowing to the Mediterranean Sea north of the Mijares Basin were the most dissimilar group. Primary and secondary freshwater species had higher province fidelity than peripheral species. Main conclusions, The results support the hypothesis that historical factors exert greater constraints on native freshwater fish assemblages in the Iberian Peninsula than do current environmental factors. After examining patterns of assemblage variation across space, as evidenced by the biogeographical provinces, we discuss the likely dispersal and speciation events that underlie these patterns. [source] Distortion of Right Superior Pulmonary Vein Anatomy by Balloon Catheters as a Contributor to Phrenic Nerve InjuryJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2009YASUO OKUMURA M.D. Introduction: Cryothermal, HIFU, and laser catheter-based balloon technologies have been developed to simplify ablation for AF. Initial enthusiasm for their widespread use has been dampened by phrenic nerve (PN) injury. The interaction between PN and pulmonary vein (PV) geometry contributing to PN injury is unclear. Methods and Results: After right thoracotomy, the PN course along the epicardial right atrial surface was mapped directly in 10 dogs. The location of the PN and its relationship with the right superior (RS) PV, and potential RSPV surface distortions after balloon inflation were established by electroanatomic mapping. In 5 dogs, the PN was captured within the RSPV, but could not be stimulated in the remaining 5 dogs. The distance between the RSPV and the PN was significantly shorter in the captured group than in the noncaptured group (6.3 ± 3.1 mm vs 10.2 ± 3.2 mm, P < 0.001). Importantly, 96% of the captured sites within the RSPV were observed at a distance >5 mm into the PV. The inflated balloon surface anteriorly extended 5.6 ± 3.7 mm outside the PV diameter, with distortion of anatomy narrowing the distance from the balloon surface to the PN to 4.8 ± 2.3 mm. (Distance of the original RSPV-to-PN: 9.4 ± 2.7 mm, P < 0.001.) Conclusion: PN injury with balloon technologies may stem from anatomic distortion of the PV orifice/PN relationship, through increasing contact or shortening the relative distance between the ablation site and the PN, even without displacement of the balloon into the PV. These data are important in the refinement of these technologies to improve procedural safety. [source] Human,gelada baboon conflict in and around the Simien Mountains National Park, EthiopiaAFRICAN JOURNAL OF ECOLOGY, Issue 3 2009Mesele Yihune Abstract The degree of conflict between gelada baboons and local communities in and around the Simien Mountains National Park was investigated and possible solutions for the existing problems are suggested. The study was carried out from September, 2005 to March, 2006 by means of questionnaire survey, direct observations on crop damage by gelada baboon and using faecal dropping analysis. Data were analysed using descriptive statistics, and responses were compared using chi-squared test and one-way ANOVA. Logistic regression model was used to determine factors that caused crop damage. The average annual crop loss by gelada baboon per household was 117 ± 10 kg. There was a positive correlation (r = 0.43, P < 0.001) between the type of crop grown and the type of crop damaged. Among the respondents, 47.3% reported serious loss of barley by gelada baboons. Analysis from the faecal droppings showed that 18% of the samples constituted barley although the extent of damage varied from village to village. Among the respondents, 60.3% cultivated only barley because of the cold weather and the type of soil in the study area. Distance from the Park and the frequency of crop damage were negatively correlated (,0.57, P < 0.001). Although farmers utilized various methods to protect their farms against gelada baboons, the most prominent method was direct watching (48.3%). To minimize the existing problems, local residents and the Park authorities should work together to identify alternative crops and land-use patterns that might not attract gelada baboons. Résumé Nous avons étudié l'importance des conflits entre les babouins geladas et les communautés locales dans et autour du Parc National des Simien Mountains, et nous suggérons d'éventuelles solutions pour les régler. L'étude a eu lieu de septembre 2005 à mars 2006, sous la forme d'une enquête par questionnaire, d'observations directes des dommages causés aux cultures par les geladas et d'analyses des excréments. Les données furent analysées au moyen de statistiques descriptives, et les réponses furent comparées par un test en ,² et une ANOVA à une voie. Un modèle de régression logistique fut utilisé pour déterminer les facteurs qui causent les dommages aux récoltes. La perte annuelle moyenne attribuée aux babouins était de 117 ± par ménage. Il y avait une corrélation positive (r = 0.43, P < 0.001) entre le type de culture pratiqué et celui qui était endommagé. 47.3% des participants à l'enquête ont rapporté de graves pertes d'orge à cause des babouins geladas. L'analyse des excréments a révélé que 18% des échantillons étaient composés d'orge mais la gravité des dommages variait d'un village à l'autre. 60.3% des participants ne cultivaient que de l'orge en raison du climat froid et du type de sol dans la zone étudiée. La distance par rapport au parc et la fréquence des dommages étaient négativement liées (,0.57, P < 0.001). Bien que les fermiers utilisent plusieurs méthodes pour protéger leurs fermes contre les geladas, la plus importante était de les surveiller directement (48.3%). Afin de minimiser les problèmes actuels, les résidants et les autorités du parc devraient travailler ensemble pour identifier des cultures alternatives et des schémas d'utilisation des sols qui puissent ne plus attirer les babouins. [source] Turnover in flightless invertebrate species composition over different spatial scales in Afrotemperate forest in the Drakensberg, South AfricaAFRICAN JOURNAL OF ECOLOGY, Issue 3 2009Charmaine Uys Abstract An understanding of species turnover at different spatial scales and the influence of environmental variables including distance are important for conservation planning and management. Ground dwelling, flightless invertebrates have poor dispersal abilities and other taxa may not be effective as surrogates. This is an important consideration for biodiversity conservation in Afrotemperate forests of the Drakensberg Mountains, South Africa, where flightless invertebrates are geographically isolated by the naturally fragmented state of forests. Seventeen Afrotemperate forests in four reserves across the Drakensberg were sampled using soil and leaf litter sampling, pitfall traps, active search quadrats and tree beats. Seventy-two species were recorded, comprising 31 mollusc, nine earthworm, one onychophoran, six centipede, twelve millipede and thirteen ant species. Canonical correspondence analysis indicated that latitude (distance); fire history (disturbance) and mean annual precipitation were the most important factors governing invertebrate assemblage composition. ,sim measurements detected change in species at all spatial scales investigated, but no clear trends were evident. Distance or spatial scale alone does not explain species turnover and community composition. Effective selection of target areas, therefore, requires species level information to identify species of special concern. Résumé Une bonne compréhension de la rotation des espèces à différentes échelles spatiales et de l'influence des variables environnementales, y compris de la distance, est importante pour la planification et la gestion de la conservation. Les invertébrés qui vivent dans le sol, ceux qui ne volent pas, n'ont que de faibles capacités de se disperser, et d'autres taxons peuvent ne pas être des substituts efficaces. Ceci pourrait être une réflexion importante pour la conservation de la biodiversité dans les forêts afro-tempérées des monts Drakensberg, en Afrique du Sud, où des invertébrés qui ne volent pas sont isolés géographiquement par l'état naturellement fragmenté des forêts. On a prélevé des échantillons dans 17 forêts afro-tempérées, dans quatre réserves du Drakensberg, en utilisant des échantillons de sols et de litière de feuilles, des pièges, la recherche active dans des quadrats et le battage d'arbres. On a enregistré 72 espèces comprenant 31 mollusques, neuf vers de terre, un onychophore, six centipèdes, 12 mille-pattes et 13 fourmis. L'analyse canonique des correspondances a indiqué que la latitude (distance), l'historique des feux (perturbations) et les précipitations annuelles moyennes étaient les facteurs les plus importants pour la composition des assemblages d'invertébrés. Des mesures de ,sim ont détecté des changements d'espèces dans toutes les échelles spatiales étudiées, mais aucune tendance nette n'était visible. L'échelle de distance ou d'espace n'explique pas seule la rotation des espèces et la composition de la communauté. La sélection effective de zones cibles requiert donc des informations au niveau des espèces pour pouvoir identifier les espèces dont le statut est particulièrement inquiétant. [source] Third-Person Effects and the Environment: Social Distance, Social Desirability, and Presumed BehaviorJOURNAL OF COMMUNICATION, Issue 2 2005Jakob D. Jensen Previous research has documented third-person effects (persons presuming that others will be more susceptible to media effects than they themselves are) and explored moderators such as social desirability (the effect reverses when the media effects are undesirable) and social distance (the effect increases as the social distance from the self increases). In a study of environmental news coverage, the authors observed the general third-person effect and the moderating role of social desirability; however, they also found that social distance affected presumed influence in complex ways reflecting varying perceptions of issue relevance for the comparison groups. A new variable, presumed behavior (the presumed effect of media coverage on others' behavior), was found to be independent of presumed influence and to offer improved prediction of perceivers' behavioral intentions. [source] The Revenge of Distance: Vulnerability Analysis of Critical Information InfrastructureJOURNAL OF CONTINGENCIES AND CRISIS MANAGEMENT, Issue 2 2004Sean P. Gorman The events of 11 September 2001 brought an increased focus on security in the United States and specifically the protection of critical infrastructure. Critical infrastructure encompasses a wide array of physical assets such as the electric power grid, telecommunications, oil and gas pipelines, transportation networks and computer data networks. This paper will focus on computer data networks and the spatial implications of their susceptibility to targeted attacks. Utilising a database of national data carriers, simulations will be run to determine the repercussions of targeted attacks and what the relative merits of different methods of identifying critical nodes are. This analysis will include comparison of current methods employed in vulnerability analysis with spatially constructed methods incorporating regional and distance variables. In addition to vulnerability analysis a method will be proposed to analyse the fusion of physical and logical networks, and will discuss what new avenues this approach reveals. The analysis concludes that spatial information networks are vulnerable to targeted attacks and algorithms based on distance metrics do a better job of identifying critical nodes than classic accessibility indexes. The results of the analysis are placed in the context of public policy posing the question do private infrastructure owners have sufficient incentives to remedy vulnerabilities in critical networks. [source] Ectomycorrhizal fungal communities at forest edgesJOURNAL OF ECOLOGY, Issue 2 2005IAN A. DICKIE Summary 1Ectomycorrhizal fungi are spatially associated with established ectomycorrhizal vegetation, but the influence of distance from established vegetation on the presence, abundance, diversity and community composition of fungi is not well understood. 2We examined mycorrhizal communities in two abandoned agricultural fields in Minnesota, USA, using Quercus macrocarpa seedlings as an in situ bioassay for ectomycorrhizal fungi from 0 to 20 m distance from the forest edge. 3There were marked effects of distance on all aspects of fungal communities. The abundance of mycorrhiza was uniformly high near trees, declined rapidly around 15 m from the base of trees and was uniformly low at 20 m. All seedlings between 0 and 8 m distance from forest edges were ectomycorrhizal, but many seedlings at 16,20 m were uninfected in one of the two years of the study. Species richness of fungi also declined with distance from trees. 4Different species of fungi were found at different distances from the edge. ,Rare' species (found only once or twice) dominated the community at 0 m, Russula spp. were dominants from 4 to 12 m, and Astraeus sp. and a Pezizalean fungus were abundant at 12 m to 20 m. Cenococcum geophilum, the most dominant species found, was abundant both near trees and distant from trees, with lowest relative abundance at intermediate distances. 5Our data suggest that seedlings germinating at some distance from established ectomycorrhizal vegetation (15.5 m in the present study) have low levels of infection, at least in the first year of growth. Distance from established vegetation represents an important gradient for ectomycorrhizal fungi, with different species occupying distinct niches along this gradient. This provides support for niche differentiation as a factor contributing to ectomycorrhizal fungal diversity. 6Ectomycorrhizal infection of seedlings is spatially complex, with high infection and high fungal diversity near trees, high infection but lower diversity at intermediate distances, and low infection and low fungal diversity distant from trees. This spatial complexity should be considered as a factor potentially influencing the establishment of ectomycorrhizal vegetation. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||