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Abstract

Relationships between species diversity and genetic diversity, the two most important elements of biodiversity, have recently attracted considerable interest in the field of community genetics. The present study contributes to this issue by addressing three questions that seem to have been ignored so far, namely whether the use of (a) different diversity measures, of (b) different components of diversity, and of (c) different genetic traits may lead to different assessements of speciesgenetic diversity relationships. For this purpose, data on species composition and genetic traits were collected from the natural regeneration of nine forest communities, which consist of three pure and six mixed tree stands located in the Thuringian forest area. The genetic traits comprised one DNA (AFLP) and five isozyme traits all of which were determined in all species. In contrast to other studies, the species diversity was determined for two components, SD (species diversity) and NeS (effective number of genetically distinct species), and the genetic diversity was determined for three components, TSGD (the transspecific genetic diversity taken over all species of a community), ISGD and NGS (each describing a special average of intraspecific genetic diversity). Each component was quantified by measures of diversity representing four orders of the Renyi/Hillfamily. The orders correspond to the degree to which prevalence of types is considered in the diversity measure (at the lowest order, known as richness, prevalence is disregarded, with increasing order, the diversity measure reports prevalent types only). In our data, the diversity measured for each genetic trait separately showed a great range of variation across traits and components of diversity even in the same stand. The choice of the diversity component thus turned out to have a substantial effect on the assessment of the level of genetic diversity within stands. This prompted more detailed studies of the relationships between species and genetic diversity. Relationships were quantified with the help of the coefficient of co-variation, and the statistical significance of the co-variations was verified through permutation tests. The co-variations between SD and TSGD were found to be generally positive and in most cases significant, but the co-variation declined with increasing orders of diversity for most of the genetic traits. In contrast, the co-variation between SD and ISGD was not consistent for the four orders of diversity. In particular, the co-variations for the highest order were found to be negative for all traits. The results of our explorative study thus demonstrate that the assessment of levels of genetic diversity within stands as well as species-genetic interrelations critically depend on the choice of the diversity component, of the order of diversity, and of the genetic trait. These observations lend support to different and even opposing hypotheses on the processes potentially generating species-genetic relationships. Therefore, strategies in the conservation of biodiversity, for example, are suggested to be related more specifically to the components and orders of diversity to be safegarded and to consider the functions of genetic traits in relation to adaptationally relevant environmental factors.

Abstract

This paper discusses glyphs of the 2-shaped or “round” allograph of the grapheme <r> with a tag protruding from the lower part of the stem, asking whether their distribution in a corpus of some 600 late Middle English texts can be meaningfully related to these texts’ localisation in A Linguistic Atlas of Late Mediaeval English. It discusses what localisation expresses, and uses regression modelling to show that there is no co-variation between the texts’ paleography and their orthography, although there is a measure of correlation between them. The evidence in favour is that the quantitative analysis identifies localisation in northings as a predictor of the occurrence of the tagged form of the allograph, which occurs at a higher frequency in texts localised below the Midlands line at c. 300 northings. The evidence against is the form’s scattered distribution according to the localisation variable where co-variation would imply a more clear-cut concentration of points, and also the moderate success at explaining the form’s distribution by means of variables known to explain orthographic variation.

Abstract

This brief review addresses two major aspects of the neural control of multi-element systems. First, theprinciple of abundance suggests that the central nervous system unites elements into synergies (co-variation ofelemental variables across trials quantified within the framework of the uncontrolled manifold hypothesis) that stabilizeimportant performance variables. Second, a novel method, analytical inverse optimization, has been introduced tocompute cost functions that define averaged across trials involvement of individual elements over a range of values oftask-specific performance variables. The two aspects reflect two features of motor coordination: (1) using variablesolutions that allow performing secondary tasks and stabilizing performance variables; and (2) selecting combinationsof elemental variables that follow an optimization principle. We suggest that the conflict between the two approaches (asingle solution vs. families of solutions) is apparent, not real. Natural motor variability may be due to using the samecost function across slightly different initial states; on the other hand, there may be variability in the cost function itselfleading to variable solutions that are all optimal with respect to slightly different cost functions. The analysis of motorsynergies has revealed specific changes associated with atypical development, healthy aging, neurological disorders, andpractice. These have allowed formulating hypotheses on the neurophysiological mechanisms involved in the synergiccontrol of actions.

The effects of missing data when surveying alcohol habits

AIMS - This study aimed at describing the effects of missing data when surveying alcohol consumption using a Random Digit Dialling procedure. METHODS - Data was part of the Monitor project including repeated monthly data on the alcohol habits in the general Swedish population. Non-respondents during four months were followed up a year later and asked to do a shortened telephone interview and were compared to a concurrent sample of respondents (n=2552 versus n=6005). Further, using a second approach, the monthly levels of non-response was related to the level of measured alcohol use in a time series analysis (n=67500). RESULTS - The results indicated no differences in the level of reported alcohol or tobacco use with except for a slightly higher proportion of alcohol abstainers in the sample of initial non-response. The time series showed no pattern of co-variation between the obtained nonresponse levels and the assessed levels of alcohol or tobacco use. CONCLUSIONS - On the basis of the results it was meaningful to make a distinction between "soft" non-respondents (responding after extensive contacting effort) and "hard" non-respondents (not responding albeit extensive effort) and the results suggest that inclusion of the "soft" non-respondents does not by necessity lead to higher levels of assessed alcohol use.

Abstract

This paper explores the patterns of aggregate cyclical behavior within the Middle East and North Africa region and among this region and the major industrialized economies. We seek to determine how the volatility and the symmetry of MENA countries have been modified following their recent liberalization initiatives. In particular, we ask the broad question of how far the MENA zone can “couple” with the most developed economies and maintain a relative synchronicity with the world business cycle over 1970-2010. The Hodrick-Prescott filter is applied to decompose the real GDP of these countries and obtain the resulting series of cyclical components. These are compared at different time horizons: the contemporary, short-term, and long-term. Two approaches are used: a static one, based on properties of variability, co-variation and correlation, and a dynamic one, based on long-term relationships using an autoregressive distributed lag models and short-term dynamics using an error correction models. A long-term convergence between the MENA, the G7, the European, and the Anglo-Saxon cycles is confirmed particularly during 1989-2010, period under which the MENA countries have engaged an important economic integration process. This could denote a coupling of the region with the industrialized nations. The idiosyncratic cycles of the MENA countries are closely associated with the G7 experience, especially, in long term. While the European cycle has an important effect on the North African countries, the Middle East region is rather more dominated by the Anglo-Saxon zone.

Abstract

This paper presents findings on the developments of PA education in 11 CEE countries and discusses various patterns based on the data on the historical background of PA education, forming thus the initial outcome of a more complex research carried out within the PAQUALITY project. The analysis is based around two main contextual factors: the role of imprinting (path-dependence) of the PA education in the framework of history and evolved PA ideologies, and the development of PA as discipline; and the role of institutional and HE legal factors on the current existence and status of PA education in the selected cluster of countries. The research question relates to the potential observation of differences in the development and current status of PA education in 11 CEE countries today. For this purpose, we utilize a co-variational international comparative case-study methodological approach, since this is a variable-centered approach, as it is acknowledged that a full-fledged theory might be absent in the framework of this specific investigation. The results indicate that we can argue in favor of the role of path-dependence in shaping PA education in CEE countries, where different starting points affected the outcomes in the content of current PA education. However, path-dependence is not to be taken as a sole factor corresponding to the development of the PA discipline in specific countries, as also more context-based factors and legal provisions do play the role. The outcome is that there is a lack of uniformity of PA education across CEE countries, where the country-specific context is the major factor in shaping the structure and content of programs, in some instances even creating new “sciences”. Although it would be expected to have some convergence in PA programs after almost three decades after the political and economic transformations started, we can even argue that PA education is more diverse now. This would give a specific role to the internalization and / or international accreditation in re-shaping and reversing the divergence processes in the future, but the anticipation for program consolidation might also be the factor that could have converging effects.

geprägten raumwissenschaftlich ausgerichteten Methodenliteratur nur eine untergeordnete Rolle (z. B. bei Mattissek/Pfaffenbach/Reuber 2013 und Farthing 2016 ). Zu erwähnen ist hier der einschlägige und immer noch lesenswerte Aufsatz von Leimbrock (1995) zu Fallstudien in der Stadtforschung, der jedoch von der Systematik des hier vorzustellenden Bandes abweicht. Wie die Autoren selbst hervorheben, ist der entscheidende Punkt ihres Buches, dass sie drei grundlegend verschiedene Ansätze bei Fallstudien unterscheiden: die co-variational analysis , das causal

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