Zur Kenntnis von Lithium-phosphor(V)-nitrid. Reindarstellung und Verfeinerung der Kristallstruktur von LiPN2

Reines Lithium-phosphor(V)-nitrid (LiPN2 ) wurde durch Festkörperreaktion der binären Nitride L i 3N und P3N5 erhalten. Die Kristallstruktur von LiPN2 wurde auf der Basis von Röntgen-Pulverdiffraktometerdaten mit Hilfe der Rietveld-Methode verfeinert (I42d; a = 457,5(2) pm; c = 711,8(3) pm; 31 beob. Reflexe 20° < 2Θ <105°; Germanium-Monochromator, CuK^; R(wp) = 0,059; R(I, hkl) = 0,061). Die Kristallstruktur von LiPN2 leitet sich vom Chalcopyrit- Typ ab. Phosphor und Stickstoff bilden ein dreidimensionales Netz eckenverknüpfter PN4 - Tetraeder (Ρ—Ν 164,5(7) pm; P-N—Ρ 123,6(8)°). Die Lithium-Kationen besetzen die verbleibenden Lücken. Sie sind verzerrt tetraedrisch von jeweils vier Stickstoff-Atomen koordiniert (Li—Ν 209,3(10) pm)

Neuroanatomische Charakterisierung blickstabilisierender Neurone an der Hirnstammmittellinie der Primaten, einschließlich des Menschen

The aim of this project was to describe the localization and the histological characteristics of a generally unknown group of neurons in the brainstem of the macaque and find homologous cell groups in man. These cells are scattered in several clusters and are known to project to the cerebellar flocculus. Büttner-Ennever und Büttner called them “cell groups of the paramedian tract” (PMT cell groups). The physiological roll of these cells could lie in the stabilization of gaze holding. 1) In this thesis the cell groups are named consecutively PMT-1 to PMT-6 from caudal to rostral. In an attempt to highlight these neurons, we tested them with a battery of “markers”. The following staining procedures were used as “markers”: • enzymatic detection of acetylcholine-esterase(AchE) • enzymatic detection of cytochrome-c-oxidase (COE) • cytochrome-c-oxidase immunocytochemistry (CO) • calretinin immunocytochemistry (CR) • calbindin immunocytochemistry (CB) • parvalbumin immunocytochemistry (PAV) • serotonin immunocytochemistry (5-HT) The results showed that the enzymatic detection of AchE and COE highlighted the PMT cell groups and their neuropile most clearly in macaque. AchE and COE were used as markers for the putative homologous cells in man. However the PMT-6 cell group was not identifiable in man with AchE or COE. The intensive neuropile staining was an important feature to identify the PMT cell groups. On the other hand the cytochrome-c-oxidase immunocytochemistry (CO) illustrated the cytoarchitecture better. 2) After the injection of 3H-leucine into premotor regions for horizontal or vertical eye movements in macaque monkeys, Büttner-Ennever et al. (1989) described labeled terminals were found in PMT cell regions. In order to check the validity of our histological markers, we compared the results with the tract tracing results in the PMT-cell regions. Thus the PMT neurons could be defined by their inputs from premotor regions. There were also found to be the region with intensive neuropil staining with AchE and COE. We were able to distinguish the PMT neurons that mainly received horizontal premotor inputs and others that mainly received vertical ones. 3) The PMT neurons are localized near the midline of the brainstem close to the raphe neurons, which are serotoninergic. This is one reason why there are sometimes mistaken for raphe neurons (McCrea et al., 1987a,b). By means of the immunocytochemical markers 5-HT (macaque) and PH8 (man) we could outline the serotoninergic “raphe neurons” and could distinguish them from the PMT neurons. In the same way we could differentiate the motoneurons from the PMT neurons in the abducens nucleus by highlighting the motoneurons with the immunocytochemical marker ChAT. 4) A clear difference in cell morphology between PMT cells and raphe cells was also found. In both macaque and man the nucleus of PMT cellsomata were larger and more clearly visible than in raphe neurons. Insofar as the PMT cells in macaque could be clearly localized and also the homologue groups in man could be found, the aim of this thesis was achieved. Additionally we could show that the cell groups PMT-1, PMT-2, PMT-3, PMT-4a, PMT-5a and PMT-5c are associated mainly with vertical premotor inputs. The groups PMT-4b and PMT-5b were mainly associated with horizontal premotor inputs. The groups PMT-4b, PMT-5b and PMT-5c were described here for the first time and must be verified in future studies

Erfolgsfaktoren von Veränderungsprozessen in der Kommunalverwaltung – am Beispiel eines Landratsamts in Baden-Württemberg

Veränderungsprozesse spielen in der sich immer schneller verändernden Umwelt eine wichtige Rolle. Die Kommunalverwaltungen spielen eine zentrale Rolle durch ihre Nähe zu Bürgerinnen und Bürgern und müssen daher ihre Leistungsfähigkeit durch eine erfolgreiche Anpassung an Veränderungen sichern. Ziel dieser Arbeit ist es, mittels einer schriftlichen Befragung zu einem aktuellen Veränderungsprozess in einem Landratsamt, Erfolgsfaktoren für eine erfolgreiche Veränderung zu ermitteln und so eine Ausgangsbasis für die Gestaltung von Veränderungsprozessen zu schaffen

Neuroanatomische Charakterisierung blickstabilisierender Neurone an der Hirnstammmittellinie der Primaten, einschließlich des Menschen

The aim of this project was to describe the localization and the histological characteristics of a generally unknown group of neurons in the brainstem of the macaque and find homologous cell groups in man. These cells are scattered in several clusters and are known to project to the cerebellar flocculus. Büttner-Ennever und Büttner called them “cell groups of the paramedian tract” (PMT cell groups). The physiological roll of these cells could lie in the stabilization of gaze holding. 1) In this thesis the cell groups are named consecutively PMT-1 to PMT-6 from caudal to rostral. In an attempt to highlight these neurons, we tested them with a battery of “markers”. The following staining procedures were used as “markers”: • enzymatic detection of acetylcholine-esterase(AchE) • enzymatic detection of cytochrome-c-oxidase (COE) • cytochrome-c-oxidase immunocytochemistry (CO) • calretinin immunocytochemistry (CR) • calbindin immunocytochemistry (CB) • parvalbumin immunocytochemistry (PAV) • serotonin immunocytochemistry (5-HT) The results showed that the enzymatic detection of AchE and COE highlighted the PMT cell groups and their neuropile most clearly in macaque. AchE and COE were used as markers for the putative homologous cells in man. However the PMT-6 cell group was not identifiable in man with AchE or COE. The intensive neuropile staining was an important feature to identify the PMT cell groups. On the other hand the cytochrome-c-oxidase immunocytochemistry (CO) illustrated the cytoarchitecture better. 2) After the injection of 3H-leucine into premotor regions for horizontal or vertical eye movements in macaque monkeys, Büttner-Ennever et al. (1989) described labeled terminals were found in PMT cell regions. In order to check the validity of our histological markers, we compared the results with the tract tracing results in the PMT-cell regions. Thus the PMT neurons could be defined by their inputs from premotor regions. There were also found to be the region with intensive neuropil staining with AchE and COE. We were able to distinguish the PMT neurons that mainly received horizontal premotor inputs and others that mainly received vertical ones. 3) The PMT neurons are localized near the midline of the brainstem close to the raphe neurons, which are serotoninergic. This is one reason why there are sometimes mistaken for raphe neurons (McCrea et al., 1987a,b). By means of the immunocytochemical markers 5-HT (macaque) and PH8 (man) we could outline the serotoninergic “raphe neurons” and could distinguish them from the PMT neurons. In the same way we could differentiate the motoneurons from the PMT neurons in the abducens nucleus by highlighting the motoneurons with the immunocytochemical marker ChAT. 4) A clear difference in cell morphology between PMT cells and raphe cells was also found. In both macaque and man the nucleus of PMT cellsomata were larger and more clearly visible than in raphe neurons. Insofar as the PMT cells in macaque could be clearly localized and also the homologue groups in man could be found, the aim of this thesis was achieved. Additionally we could show that the cell groups PMT-1, PMT-2, PMT-3, PMT-4a, PMT-5a and PMT-5c are associated mainly with vertical premotor inputs. The groups PMT-4b and PMT-5b were mainly associated with horizontal premotor inputs. The groups PMT-4b, PMT-5b and PMT-5c were described here for the first time and must be verified in future studies

Vergleich von Texten verschiedener Autoren über Entwicklung und Struktur der französischen Sprache während des 100 Jährigen Krieges

Entwicklung und Struktur der französischen Sprache

An experimental method for evoking and characterizing dynamic color patterning of cuttlefish during prey capture

© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kim, D., Buresch, K. C., Hanlon, R. T., & Kampff, A. R. An experimental method for evoking and characterizing dynamic color patterning of cuttlefish during prey capture. Journal of Biological Methods, 9(2), (2022): e161, https://doi.org/10.14440/jbm.2022.386.Cuttlefish are active carnivores that possess a wide repertoire of body patterns that can be changed within milliseconds for many types of camouflage and communication. The forms and functions of many body patterns are well known from ethological studies in the field and laboratory. Yet one aspect has not been reported in detail: the category of rapid, brief and high-contrast changes in body coloration (“Tentacle Shot Patterns” or TSPs) that always occur with the ejection of two ballistic tentacles to strike live moving prey (“Tentacles Go Ballistic” or TGB moment). We designed and tested a mechanical device that presented prey in a controlled manner, taking advantage of a key stimulus for feeding: motion of the prey. High-speed video recordings show a rapid transition into TSPs starting 114 ms before TGB (N = 114). TSPs are then suppressed as early as 470–500 ms after TGB (P < 0.05) in unsuccessful hunts, while persisting for at least 3 s after TGB in successful hunts. A granularity analysis revealed significant differences in the large-scale high-contrast body patterning present in TSPs compared to the camouflage body pattern deployed beforehand. TSPs best fit the category of secondary defense called deimatic displaying, meant to briefly startle predators and interrupt their attack sequence while cuttlefish are distracted by striking prey. We characterize TSPs as a pattern category for which the main distinguishing feature is a high-contrast signaling pattern with aspects of Acute Conflict Mottle or Acute Disruptive Pattern. The data and methodology presented here open opportunities for quantifying the rapid neural responses in this visual sensorimotor set of behaviors.KCB and RTH acknowledge partial support from the Sholley Foundation

Octopus arms exhibit exceptional flexibility

© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kennedy, E. B. L., Buresch, K. C., Boinapally, P., & Hanlon, R. T. Octopus arms exhibit exceptional flexibility. Scientific Reports, 10(1), (2020): 20872. doi:10.1038/s41598-020-77873-7.The octopus arm is often referred to as one of the most flexible limbs in nature, yet this assumption requires detailed inspection given that this has not been measured comprehensively for all portions of each arm. We investigated the diversity of arm deformations in Octopus bimaculoides with a frame-by-frame observational analysis of laboratory video footage in which animals were challenged with different tasks. Diverse movements in these hydrostatic arms are produced by some combination of four basic deformations: bending (orally, aborally; inward, outward), torsion (clockwise, counter-clockwise), elongation, and shortening. More than 16,500 arm deformations were observed in 120 min of video. Results showed that all eight arms were capable of all four types of deformation along their lengths and in all directions. Arms function primarily to bring the sucker-lined oral surface in contact with target surfaces. Bending was the most common deformation observed, although the proximal third of the arms performed relatively less bending and more shortening and elongation as compared with other arm regions. These findings demonstrate the exceptional flexibility of the octopus arm and provide a basis for investigating motor control of the entire arm, which may aid the future development of soft robotics.We gratefully acknowledge funding from Grant N00014-19-1-2445 from the Office of Naval Research, Tom McKenna and Marc Steinberg, Program Managers. We also thank the staff of the Marine Resources Center at MBL for assistance with water quality measurements, seawater system maintenance, and collection of food items for octopuses

Expression of squid iridescence depends on environmental luminance and peripheral ganglion control

Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Company of Biologists for personal use, not for redistribution. The definitive version was published in Journal of Experimental Biology 217 (2014):850-858, doi:10.1242/​jeb.091884.Squids display impressive changes in body coloration that are afforded by two types of dynamic skin elements: structural iridophores (which produce iridescence) and pigmented chromatophores. Both color elements are neurally controlled, but nothing is known about the iridescence circuit, or the environmental cues, that elicit iridescence expression. To tackle this knowledge gap, we performed denervation, electrical stimulation and behavioral experiments using the long-fin squid, Doryteuthis pealeii. We show that while the pigmentary and iridescence circuits originate in the brain, they are wired differently in the periphery: (i) the iridescence signals are routed through a peripheral center called the stellate ganglion and (ii) the iridescence motorneurons likely originate within this ganglion (as revealed by nerve fluorescence dye fills). Cutting the inputs to the stellate ganglion that descend from the brain shifts highly reflective iridophores into a transparent state. Taken together, these findings suggest that although brain commands are necessary for expression of iridescence, integration with peripheral information in the stellate ganglion could modulate the final output. We also demonstrate that squids change their iridescence brightness in response to environmental luminance; such changes are robust but slow (minutes to hours). The squid's ability to alter its iridescence levels may improve camouflage under different lighting intensities.This research was supported by the ONR Basic Research Challenge grant no. N00014-10-1-0989 and by the AFOSR grant FA9950090346.2015-03-1