On Hilbert-Schmidt operator formulation of noncommutative quantum mechanics

This work gives value to the importance of Hilbert-Schmidt operators in the formulation of a noncommutative quantum theory. A system of charged particle in a constant magnetic field is investigated in this framework

Unique establishment of procephalic head segments is supported by the identification of cis-regulatory elements driving segment-specific segment polarity gene expression in Drosophila

Anterior head segmentation is governed by different regulatory mechanisms than those that control trunk segmentation in Drosophila. For segment polarity genes, both initial mode of activation as well as cross-regulatory interactions among them differ from the typical genetic circuitry in the trunk and are unique for each of the procephalic segments. In order to better understand the segment-specific gene network responsible for the procephalic expression of the earliest active segment polarity genes wingless and hedgehog, we started to identify and analyze cis-regulatory DNA elements of these genes. For hedgehog, we could identify a cis-regulatory element, ic-CRE, that mediates expression specifically in the posterior part of the intercalary segment and requires promoter-specific interaction for its function. The intercalary stripe is the last part of the metameric hedgehog expression pattern that appears during embryonic development, which probably reflects the late and distinct establishment of this segment. The identification of a cis-regulatory element that is specific for one head segment supports the mutant-based observation that the expression of segment polarity genes is governed by a unique gene network in each of the procephalic segments. This provides further indication that the anterior-most head segments represent primary segments, which are set up independently, in contrast to the secondary segments of the trunk, which resemble true repetitive units

ICAR: endoscopic skull‐base surgery

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Cardiovascular mechanisms during thermoregulation in reptiles

Vertebrates may control heat transfer with the environment by differentially changing heart rate and blood flow during heating and cooling. In reptiles, the ecological benefit of this physiological thermoregulation is a pronounced increase in the time spent at a "high" body temperature during the day. During heating and cooling in a lizard, the cardiovascular system is controlled by prostaglandins and to a lesser extent by the autonomic nervous system. There are, however, pronounced phylogenetic differences in cardiovascular control mechanisms of thermoregulating reptiles. Additionally, the characteristic heart rate "hysteresis" pattern also occurs in a crustacean, pointing towards parallel evolution of control mechanisms alongside increasing vascularisation

Germ cells in the crustacean Parhyale hawaiensis depend on Vasa protein for their maintenance but not for their formation

Germ cells are a population of cells that do not differentiate to form somatic tissue but form the egg and sperm that ensure the reproduction of the organism. To understand how germ cells form, holds a key for identifying what sets them apart from all other cells of the organism. There are large differences between embryos regarding where and when germ cells form but the expression of Vasa protein is a common trait of germ cells. We studied the role of vasa during germ cell formation in the crustacean Parhyale hawaiensis. In a striking difference to the posterior specification of the group of germ cells in the arthropod model Drosophila, all germ cells in Parhyale originate from a single germ line progenitor cell of the 8-cell stage. We found vasa RNA ubiquitously distributed from 1-cell to 16-cell stage in Parhyale and localized to the germ cells from 32-cell stage onwards. Localization of vasa RNA to the germ cells is controlled by its 3'UTR and this could be mimicked by fluorescently labeled 3'UTR RNA. Vasa protein was first detectable at the 100-cell stage. MO-mediated inhibition of vasa translation caused germ cells to die after gastrulation. This means that in Parhyale Vasa protein is not required for the initial generation of the clone of germ cells but is required for their subsequent proliferation and maintenance. It also means that the role of vasa changed substantially during an evolutionary switch in the crustaceans by Parhyale from the specification of a group of germ cells to that of a single germ line progenitor. This is the first functional study of vasa in an arthropod beyond Drosophila