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N-acetylation of arylalkylmines (serotonin and tryptamine) in the crayfish brain.

1. The presence of N-acetyltransferase in the crayfish brain (Pacifastacus leniusculus) was investigated. The arylalkylamines tryptamine and 14C-serotonin, are acetylated by crayfish brain homogenates with the acetyl donors 3H-acetyl coenzyme A and N, S-diacetylcysteamine, respectively.2. Resolution of serotonin metabolites by thin layer chromatography (chloroform/methanol/glacial acetic acid, 93

Identification of L-3,4-dihydroxyphenylalanine in the brain of the crayfish Pacifastacus leniusculus (Dana) and in tentacles of the sea anemone Metridium senile (L) by use of gas chromatography-mass spectrometry.

1. The amino acid l-3,4-dihydroxyphenylalanine (l-DOPA) was extracted from tentacles of the sea anemone Metridium senile and from brains of the crayfish Pacifastacus leniuscuius.2. The identity of l-DOPA was ascertained by gas chromatography-mass spectrometry as the heptafluorobutyryl iso-butyl ester derivative. Dopa is identified with GC-MS for the first time and the derivatization is a novel mod

Gland cells in the tentacles of the jellyfish Cyanea lamarcki reactive with an antibody against 5-hydroxytryptamine.

A light- and electron-microscopic immunocytochemical study on the localization of 5-hydroxytryptamine in Cyanea lamarcki revealed a reaction product in the epidermal gland cells surrounding the nematocyst clusters. The closely related scyphozoan medusa Cyanea capillata lacked a reaction product in the similar mucus-producing gland cells. Earlier conflicting views on the presence and localization o

Single modified cilia displayed by cells of human internal stratifed epithelia (oral cavity, vagina)

Serial sections of human vaginal and keratinized oral-gingival epithelia were investigated for ciliary structures. Most melanocytes of the gingival epithelium lacked cilia, whereas almost all basal keratinocytes of the deeper portion of the epithelial ridges possessed one cilium each. In the suprabasal layers of the ridges only a few keratinocytes exhibited a single cilium. In the basal layer, at

Presence of 3 4-dihydroxyphenylalanine and 3,4,5-trihydroxyphenylalanine in a coelenterate nervous system: possible tyrosinase-mediated accumulation.

3,4-dihydroxyphenylalanine (DOPA), 3,4,5-trihydroxyphenylalanine (5-OH-DOPA), 5-S-cysteinylDOPA (5-SC.D) and 2-S-cysteinylDOPA (2-SC.D) in the tentacles of the sea anemone, Metridium senile, were studied by the combined use of differential centrifugation of tissue homogenates, ultracentrifugation on sucrose density gradients, HPLC and electron microscopy. DOPA, 5-OH-DOPA and o-diphenol:O2 oxidored

The Role of Public Transport in Society—A Case Study of General Policy Documents in Sweden

Abstract: The aim of this paper is to study how local governments in Sweden view the role of public transport in society, and to investigate how public transport is used in a strategic capacity. By studying general policy documents, the ambition is to gain a wider understanding of the role of public transport based on the societal context it is situated in. Documents from 15 regions and 27 municipThe aim of this paper is to study how local governments in Sweden view the role of public transport in society, and to investigate how public transport is used in a strategic capacity. By studying general policy documents, the ambition is to gain a wider understanding of the role of public transport based on the societal context it is situated in. Documents from 15 regions and 27 municipalities ha

Competition between managed honeybees and wild bumblebees depends on landscape context

Honeybees might outcompete wild bees by depleting common resources, possibly more so in simplified landscapes where flower-rich habitats have been lost. We tested this by experimentally adding honeybee hives to nine sites while ensuring that ten additional sites were free from hives. The landscape surrounding each geographically separated site either held low (homogeneous landscape) or high (heter

Reconstructing Recent Work on Macrosocial Stress as a Research Program

We reconstruct recent work on macrosocial stress (Chou, Parmar, & Galinsky, 2016) as if it were an instance of a research strategy that tests point-alternative hypotheses within a full-fledged research program. Because this strategy is free of various deficits that beset dominant strategies (e.g., meta-analysis, Bayes factor analysis), our article demonstrates one way in which the confidence c

Association between uterine artery Doppler blood flow changes and arterial wall elasticity in pregnant women

Introduction: Uterine artery (UtA) Doppler velocimetry changes and increased arterial stiffness are associated with preeclampsia. We aimed to investigate the relation between UtA velocimetry changes and arterial stiffness in pregnant women. Methods: Doppler velocimetry and photoplethysmographic digital pulse wave analysis (DPA) were performed in 173 pregnant women in the second or the third trimes

Krigets sociologi: : Analyser av krigsvåld, koncentrationsläger, offerskap och försoning

I tidigare forskning om krig presenteras ofta ensidiga bilder av fenomenen krigsvåld, offerskap och försoning. Denna bok utgår från berättelser av överlevande efter kriget i Bosnien under 1990-talet. Syftet är att analysera hur de intervjuade beskriver dessa fenomen samt vilka diskursiva mönster som framträder i konstruktionen av begreppen ”offer” och ”förövare”. Mina frågeställningar är: Hur beskThis book analyzes verbally depicted experiences of survivors from the war in Bosnia and Herzegovina. One purpose to describe how the actors portray the social phenomenon of “war violence” “victimhood” and “reconciliation”, and the second aim is to analyze discursive patterns that emerges in the creation of the terms “victim” and “perpetrator”. My research questions are: (1) How do the interviewee

Process contributions of Australian ecosystems to interannual variations in the carbon cycle

New evidence is emerging that semi-arid ecosystems dominate interannual variability (IAV) of the global carbon cycle, largely via fluctuating water availability associated with El Niño/Southern Oscillation. Recent evidence from global terrestrial biosphere modelling and satellite-based inversion of atmospheric CO2 point to a large role of Australian ecosystems in global carbon cycle variability, i

Variability in the sensitivity among model simulations of permafrost and carbon dynamics in the permafrost region between 1960 and 2009

A significant portion of the large amount of carbon (C) currently stored in soils of the permafrost region in the Northern Hemisphere has the potential to be emitted as the greenhouse gases CO2 and CH4 under a warmer climate. In this study we evaluated the variability in the sensitivity of permafrost and C in recent decades among land surface model simulations over the permafrost region between 19

Key knowledge and data gaps in modelling the influence of CO2 concentration on the terrestrial carbon sink

Primary productivity of terrestrial vegetation is expected to increase under the influence of increasing atmospheric carbon dioxide concentrations ([CO2]). Depending on the fate of such additionally fixed carbon, this could lead to an increase in terrestrial carbon storage, and thus a net terrestrial sink of atmospheric carbon. Such a mechanism is generally believed to be the primary global driver

Vegetation-climate feedbacks modulate rainfall patterns in Africa under future climate change

Africa has been undergoing significant changes in climate and vegetation in recent decades, and continued changes may be expected over this century. Vegetation cover and composition impose important influences on the regional climate in Africa. Climate-driven changes in vegetation structure and the distribution of forests versus savannah and grassland may feed back to climate via shifts in the sur

A model inter-comparison study to examine limiting factors in modelling Australian tropical savannas

The savanna ecosystem is one of the most dominant and complex terrestrial biomes, deriving from a distinct vegetative surface comprised of co-dominant tree and grass populations. While these two vegetation types co-exist functionally, demographically they are not static but are dynamically changing in response to environmental forces such as annual fire events and rainfall variability. Modelling s

Evaluation of air-soil temperature relationships simulated by land surface models during winter across the permafrost region

A realistic simulation of snow cover and its thermal properties are important for accurate modelling of permafrost. We analyse simulated relationships between air and near-surface (20 cm) soil temperatures in the Northern Hemisphere permafrost region during winter, with a particular focus on snow insulation effects in nine land surface models, and compare them with observations from 268 Russian st

In search of the severity dimension of traffic events: Extended Delta-V as a traffic conflict indicator

Most existing traffic conflict indicators do not sufficiently take into account the severity of the injuries resulting from a collision had it occurred. Thus far, most of the indicators that have been developed express the severity of a traffic encounter as their proximity to a collision in terms of time or space.This paper presents the theoretical framework and the first implementation of Extende

Coordination between governance actors in universities : the role of policy documents

This article focuses on coordination between governance actors in a public university. The purpose of this paper is to illustrate and analyze policy documents as governance tools that allow departmental management to coordinate with the authorities, the board, and the management at different university levels. A central finding is that the importance of policy documents as governance tools takes e

Major Intrinsic Proteins - Structure, function, interactions

Denna avhandling behandlar två essentiella ting, vatten som är grundläggande för allt liv på jorden och kväve, vilket är ett grundämne som återfinns i varje protein och DNA. Liksom allt annat, måste dessa ämnen hålla en lagom nivå i cellen. För att klara variationer i tillgänglighet av dessa ämnen, har alla livsformer hittat sätt att påverka upptag och frisättning av dem. För att realisera detta pMajor intrinsic proteins, also referred to as aquaporins (AQPs) are localized in membranes of all domains of life to increase the permeability to water or other small, polar molecules. Several monophyletic groups can be discerned in this large and divergent protein superfamily. Members within these subfamilies commonly show a similar substrate selectivity established by conserved filters. Comparis