Filtyp
While it is generally accepted that honeybees (Apis mellifera) are capable of using the pattern of polarized light in the sky to navigate to a food source, there is little or no direct behavioural evidence that they actually do so. We have examined whether bees can be trained to find their way through a maze composed of four interconnected tunnels, by using directional information provided by pola
The optical properties of the crystalline lenses were studied in a variety of large predatory teleosts (bony fishes) that forage in the open ocean, some of them at considerable depths. We found the first fish lenses that are free of measurable longitudinal spherical aberration, i.e., are perfectly monofocal, in contrast to the multifocal lenses that are typical for smaller fishes living close to t
This paper presents an existence theory for small-amplitude Stokes and solitary-wave solutions to the classical water-wave problem in the absence of surface tension and with an arbitrary distribution of vorticity. The hydrodynamic problem is formulated as an infinite-dimensional Hamiltonian system in which the horizontal spatial coordinate is the time-like variable. A centre-manifold technique is
Background: Positive intersexual genetic correlations are typically viewed as constraining the evolution of sexual dimorphism, when traits are subject to sexually antagonistic selection. Our study species, the damselfly Ischnura elegans, has a female-limited colour polymorphism with three female colour morphs (males are monomorphic), one of which is considered to be a male mimic. Questions: Are th
In high-risk pregnancies, the transport of oxygen and nutrients from maternal to fetal blood via the placenta is often impaired. To assess the risk, pulsed Doppler ultrasound (US) is used to evaluate the flow velocity waveform in the umbilical artery with the pulsatility index (PI), which is derived from the velocity envelope of the Doppler power spectrum. However, simply listening to the Doppler
Efficient and realistic mm-wave channel models are of vital importance for the development of novel mm-wave wireless technologies. Though many of the current 60 GHz channel models are based on the useful concept of multi-path clusters, only a limited number of 60 GHz channel measurements have been reported in the literature for this purpose. Therefore, there is still a need for further measurement
Two methods used to determine stored VOC (volatile organic compounds) in concrete slabs has been compared. These methods are frequently used in investigating indoor environment problems where emissions from moisture damaged floorings are suspected. Comparative measurements were made in situ, and the results show good agreement with expected values, especially in measurements of a profile at severa
MARS is the system established and maintained by the European Commission in order to collect information related to major industrial accidents in EU Member States in the context of the Seveso II Directive. One of the main purposes of the MARS database is to provide information for learning from the accidents to avoid similar events. Probably, the most important issue for the learning is the determ
In fish of the Squalius alburnoides complex, hybridisation and polyploidy have affected sex ratios, resulting in strong correlations between sex and genotype. The preponderance of females among triploids and the occurrence of an all male lineage among diploids seem to imply that sex ratio deviations should have a strong genetic basis. Until now, no information has been gathered regarding the molec
Sediment sequences spanning the last 800 years from two small lakes in the south Swedish uplands were explored for assessment of effects of changing human population, local land-use practices and airborne pollution on lake-ecosystem functioning and resilience. Variations in nutrient cycling and deposition of lithogenic elements were studied, using a multi-proxy stratigraphic approach. Carbon and n
The interpretation of myocardial perfusion scintigraphy (MPS) largely relies on visual assessment by the physician of the localization and extent of a perfusion defect. The aim of this study was to introduce the concept of the perfusion vector as a new objective quantitative method for further assisting the visual interpretation and to test the concept using simulated MPS images as well as patient
The recent growth in research on "good governance" and the quality of government institutions has been propelled by empirical findings that show that such institutions may hold the key to understanding economic growth and social welfare in developing and transition countries. We argue, however, that a key issue has not been addressed, namely, what quality of government (QoG) actually means at the
Recent work on conditional reasoning argues that denying the antecedent [DA] and affirming the consequent [AC] are defeasible but cogent patterns of argument, either because they are effective, rational, albeit heuristic applications of Bayesian probability, or because they are licensed by the principle of total evidence. Against this, we show that on any prevailing interpretation of indicative co
An intermolecular Pauson-Khand reaction involving a carbohydrate scaffold having a pendant alkyne provides galactose derivatives with a cyclopentenone moiety in the C3-position in up to 85% yield.
The phase equilibria of the Au–In–Ga system were investigated for the first time using Differential Thermal Analysis (DTA), X-Ray Diffractometry (XRD), Energy Dispersive X-ray Spectroscopy (EDS) and Scanning Electron Microscopy (SEM). A new ternary phase (Au2InGa2) with the hexagonal structure (P63/mmc) was discovered which melts incongruently at 394 °C. From the experimental results, several inva
The African continent has been severely affected by the HIV and AIDS pandemic and as a consequence, development is being obstructed. Agriculture and food production systems are changing as a result of the burden of the pandemic. Many farming families are experiencing trauma from morbidity and mortality as well as facing labour losses and exhaustion. To further exacerbate the situation, climate var
This essay examines the film News from Ideological Antiquity (2008) by German filmmaker Alexander Kluge. Kluge has tried to fulfil the dream of Soviet filmmaker Sergei Eisenstein and make a film version of The Capital by Karl Marx. Kluge’s endeavour is discussed within the context of European left wing cinema, and the film analysis is intertwined with a mapping of the reception of the work in Euro
Hematopoietic stem cells (HSCs) reside in the bone marrow (BM) of adult individuals and function to produce and regenerate the entire blood and immune system over the course of an individual's lifetime. Historically, HSCs are among the most thoroughly characterized tissue-specific stem cells. Despite this, the regulation of fate options, such as self-renewal and differentiation, has remained elusi
