Refine
Year of publication
- 2012 (960) (remove)
Document Type
- Article (960) (remove)
Language
- English (960) (remove)
Keywords
- Curriculum Framework (15)
- European values education (15)
- Europäische Werteerziehung (15)
- Familie (15)
- Family (15)
- Lehrevaluation (15)
- Studierendenaustausch (15)
- Unterrichtseinheiten (15)
- curriculum framework (15)
- lesson evaluation (15)
Institute
- Institut für Physik und Astronomie (175)
- Institut für Biochemie und Biologie (170)
- Institut für Geowissenschaften (142)
- Institut für Chemie (140)
- Department Psychologie (54)
- Institut für Ernährungswissenschaft (38)
- Institut für Mathematik (28)
- Department Linguistik (25)
- Institut für Informatik und Computational Science (23)
- Department Sport- und Gesundheitswissenschaften (20)
The Garzn Complex of the Garzn Massif in SW Colombia is composed of the Vergel Granulite Unit (VG) and the Las Margaritas Migmatite Unit (LMM). Previous studies reveal peak temperature conditions for the VG of about 740 A degrees C. The present study considers the remarkable exsolution phenomena in feldspars and pyroxenes and titanium-in-quartz thermometry. Recalculated ternary feldspar compositions indicate temperatures around 900-1,000 A degrees C just at or above the ultra-high temperature-metamorphism (UHTM) boundary of granulites. The calculated temperatures range of exsolved ortho- and clinopyroxenes also supports the existence of an UHTM event. In addition, titanium-in-quartz thermometry points towards ultra-high temperatures. It is the first known UHTM crustal segment in the northern part of South America. Although a mean geothermal gradient of ca 38 A degrees C km(-1) could imply additional heat supply in the lower crust controlling this extreme of peak metamorphism, an alternative model is suggested. The formation of the Vergel Granulite Unit is supposed to be formed in a continental back-arc environment with a thinned and weakened crust behind a magmatic arc (Guapotn-Mancagua Gneiss) followed by collision. In contrast, rocks of the adjacent Las Margaritas Migmatite Unit display "normal" granulite facies temperatures and are formed in a colder lower crust outside the arc, preserved by the Guapotn-Mancagu Gneiss. Back-arc formation was followed by inversion and thickening of the basin. The three units that form the modern-day Garzn Massif, were juxtaposed upon each other during collision (at ca. 1,000 Ma) and exhumation. The collision leading to the deformation of the studied area is part of the Grenville orogeny leading to the amalgamation of Rodinia.
Innovation response behaviour is defined as individuals novelty-supporting or novelty-impeding action when navigating innovation initiatives through the organization. A typology of innovation response behaviour is developed, distinguishing between active and passive modes of conduct for novelty-supporting and novelty-impeding behaviour, respectively. The antecedents of innovation response behaviour are delineated based on West and Farr's five-factor model of individual innovation. Moreover, we argue that within organizational contexts, individuals often fail to implement their ideas due to innovation barriers, perceived as factors that are beyond their control. Based on the theory of planned behaviour, we reveal how these barriers influence individuals intentional and exhibited innovation response behaviour. Propositions about proximal and distal antecedents of individuals innovation response behaviour are derived. Proposing a research framework to study the organizational process of innovation from an actor-based perspective, this paper intends to link existing research on individual innovation with the process of innovation at the organizational level, explicitly accounting for the socio-political dynamics and arising managerial problems associated with successful innovation implementation within organizational realities. Implications for research in innovation management are discussed and avenues for future research outlined.
The actual evapotranspiration is an important, but difficult to determine, element in the water balance of lakes and their catchment areas. Reliable data on evapotranspiration are not available for most lake basins for which paleoclimate reconstructions and modeling have been performed, particularly those in remote parts of Africa. We have used thermal infrared multispectral data for 14 ASTER scenes from the TERRA satellite to estimate the actual evapotranspiration in the 12,800 km(2) catchment of the Suguta Valley, northern Kenya Rift Evidence from sediments and paleo-shorelines indicates that, during the African Humid Period (AHP, 14.8 to 5.5 kyrs BP), this valley contained a large lake, 280 m deep and covering similar to 2200 km(2), which has now virtually disappeared. Evapotranspiration estimates for the Suguta Basin were generated using the Surface Energy Balance Algorithm for Land (SEBAL). Climate data required for the model were extracted from a high-resolution gridded dataset obtained from the Climatic Research Unit (East Anglia, UK). Results suggest significant spatial variations in evapotranspiration within the catchment area (ranging from 450 mm/yr in the basin to the north to 2000 mm/yr in more elevated areas) and precipitation that was similar to 20% higher during the AHP than in recent times. These results are in agreement with other estimates of paleo-precipitation in East Africa. The extreme response of the lake system (similar to 280 m greater water depth than today, and a lake surface area of 2200 km(2)) to only moderately higher precipitation illustrates the possible sensitivity of this area to future climate change.
A temporary seismic network composed of 11 stations was installed in the city of Potenza (Southern Italy) to record local and regional seismicity within the context of a national project funded by the Italian Department of Civil Protection (DPC). Some stations were moved after a certain time in order to increase the number of measurement points, leading to a total of 14 sites within the city by the end of the experiment. Recordings from 26 local earthquakes (M-l 2.2-3.8 ) were analyzed to compute the site responses at the 14 sites by applying both reference and non-reference site techniques. Furthermore, the Spectral Intensity (SI) for each local earthquake, as well as their ratios with respect to the values obtained at a reference site, were also calculated. In addition, a field survey of 233 single station noise measurements within the city was carried out to increase the information available at localities different from the 14 monitoring sites. By using the results of the correlation analysis between the horizontal-to-vertical spectral ratios computed from noise recordings (NHV) at the 14 selected sites and those derived by the single station noise measurements within the town as a proxy, the spectral intensity correction factors for site amplification obtained from earthquake analysis were extended to the entire city area. This procedure allowed us to provide a microzonation map of the urban area that can be directly used when calculating risk scenarios for civil defence purposes. The amplification factors estimated following this approach show values increasing along the main valley toward east where the detrital and alluvial complexes reach their maximum thickness.
This paper presents a highly effective compactor architecture for processing test responses with a high percentage of x-values. The key component is a hierarchical configurable masking register, which allows the compactor to dynamically adapt to and provide excellent performance over a wide range of x-densities. A major contribution of this paper is a technique that enables the efficient loading of the x-masking data into the masking logic in a parallel fashion using the scan chains. A method for eliminating the requirement for dedicated mask control signals using automated test equipment timing flexibility is also presented. The proposed compactor is especially suited to multisite testing. Experiments with industrial designs show that the proposed compactor enables compaction ratios exceeding 200x.
Background: Mediterranean temporary water bodies are important reservoirs of biodiversity and host a unique assemblage of diapausing aquatic invertebrates. These environments are currently vanishing because of increasing human pressure. Chirocephalus kerkyrensis is a fairy shrimp typical of temporary water bodies in Mediterranean plain forests and has undergone a substantial decline in number of populations in recent years due to habitat loss. We assessed patterns of genetic connectivity and phylogeographic history in the seven extant populations of the species from Albania, Corfu Is. (Greece), Southern and Central Italy.
Methodology/Principal Findings: We analyzed sequence variation at two mitochondrial DNA genes (Cytochrome Oxidase I and 16s rRNA) in all the known populations of C. kerkyrensis. We used multiple phylogenetic, phylogeographic and coalescence-based approaches to assess connectivity and historical demography across the whole distribution range of the species. C. kerkyrensis is genetically subdivided into three main mitochondrial lineages; two of them are geographically localized (Corfu Is. and Central Italy) and one encompasses a wide geographic area (Albania and Southern Italy). Most of the detected genetic variation (approximate to 81%) is apportioned among the aforementioned lineages.
Conclusions/Significance: Multiple analyses of mismatch distributions consistently supported both past demographic and spatial expansions with the former predating the latter; demographic expansions were consistently placed during interglacial warm phases of the Pleistocene while spatial expansions were restricted to cold periods. Coalescence methods revealed a scenario of past isolation with low levels of gene flow in line with what is already known for other co-distributed fairy shrimps and suggest drift as the prevailing force in promoting local divergence. We recommend that these evolutionary trajectories should be taken in proper consideration in any effort aimed at protecting Mediterranean temporary water bodies.
In this study we used molecular markers to screen for the occurrence and prevalence of the three most common haemosporidian genera (Haemoproteus, Plasmodium, and Leucocytozoon) in blood samples of the Philippine Bulbul (Hypsipetes philippinus), a thrush-size passerine bird endemic to the Philippine Archipelago. We then used molecular data to ask whether the phylogeographic patterns in this insular host-parasite system might follow similar evolutionary trajectories or not. We took advantage of a previous study describing the pattern of genetic structuring in the Philippine Bulbul across the Central Philippine Archipelago (6 islands, 7 populations and 58 individuals; three mitochondrial DNA genes). The very same birds were here screened for the occurrence of parasites by species-specific PCR assays of the mitochondrial cytochrome b gene (471 base pairs). Twenty-eight out of the 58 analysed birds had Haemoproteus (48%) infections while just 2% of the birds were infected with either Leucocytozoon or Plasmodium. Sixteen of the 28 birds carrying Haemoproteus had multiple infections. The phylogeography of the Philippine Bulbul mostly reflects the geographical origin of samples and it is consistent with the occurrence of two different subspecies on (1) Semirara and (2) Carabao, Boracay, North Gigante, Panay, and Negros, respectively. Haemoproteus phylogeography shows very little geographical structure, suggesting extensive gene flow among locations. While movements of birds among islands seem very sporadic, we found co-occurring evolutionary divergent parasite lineages. We conclude that historical processes have played a major role in shaping the host phylogeography, while they have left no signature in that of the parasites. Here ongoing population processes, possibly multiple reinvasions mediated by other hosts, are predominant.
Hidden diversity in diatoms of Kenyan Lake Naivasha a genetic approach detects temporal variation
(2012)
This study provides insights into the morphological and genetic diversity in diatoms occurring in core sediments from tropical lakes in Kenya. We developed a genetic survey technique specific for diatoms utilizing a short region (7667 bp) of the ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) gene as genetic barcode. Our analyses (i) validated the use of rbcL as a barcoding marker for diatoms, applied to sediment samples, (ii) showed a significant correlation between the results obtained by morphological and molecular data and (iii) indicated temporal variation in diatom assemblages on the inter- and intra-specific level. Diatom assemblages from a short core from Lake Naivasha show a drastic shift over the last 200 years, as littoral species (e.g. Navicula) are replaced by more planktonic ones (e.g. Aulacoseira). Within that same period, we detected periodic changes in the respective frequencies of distinct haplotype groups of Navicula, which coincide with wet and dry periods of Lake Naivasha between 1820 and 1938 AD. Our genetic analyses on historical lake sediments revealed inter- and intra-specific variation in diatoms, which is partially hidden behind single morphotypes. The occurrence of particular genetic lineages is probably correlated with environmental factors.
In this study, we report the genetic population structure of the Fire-bellied toad Bombina bombina in Brandenburg (East Germany) in the context of conservation. We analysed 298 samples originating from 11 populations in Brandenburg using mitochondrial control region sequences and six polymorphic microsatellite loci. For comparison, we included one population each from Poland and Ukraine into our analysis. Within Brandenburg, we detected a moderate variability in the mitochondrial control region (19 different haplotypes) and at microsatellite loci (9-12 alleles per locus). These polymorphisms revealed a clear population structure among toads in Brandenburg, despite a relatively high overall population density and the moderate size of single populations (100-2000 individuals). The overall genetic population structure is consistent with a postglacial colonization from South East-Europe and a subsequent population expansion. Based on genetic connectivity, we infer Management Units (MUs) as targets for conservation. Our genetic survey identified MUs, within which human infrastructure is currently preventing any genetic exchange. We also detect an unintentional translocation from South East to North West Brandenburg, presumably in the course of fish stocking activities. Provided suitable conservation measures are taken, Brandenburg should continue to harbor large populations of this critically endangered species.
Fourteen microsatellite markers were isolated and characterized for the endangered Visayan tarictic hornbill (Penelopides panini, Aves: Bucerotidae). In an analysis of 76 individuals, the number of alleles per locus varied from one to 12. Expected and observed heterozygosity ranged from 0.00 to 0.87 and from 0.00 to 0.89, respectively. All primers also amplify microsatellite loci in Luzon tarictic hornbill (Penelopides manillae), Mindanao tarictic hornbill (Penelopides affinis), the critically endangered Walden's hornbill (Aceros waldeni) and the near-threatened writhed hornbill (Aceros leucocephalus). Two loci which are monomorphic in P. panini were found polymorphic in at least one of the other species. These 14 new microsatellite markers specifically developed for two genera of Philippine hornbills, in combination with those already available for the hornbill genera Buceros and Bucorvus, comprise a reasonable number of loci to genetically analyse wild and captive populations of these and probably other related, often endangered hornbills.