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Subcellular localization of neuronal nitric oxide synthase in the brain of a teleost; an immunoelectron and confocal microscopical study

The subcellular localization of neuronal nitric oxide (NO) synthase (NOS)-immunoreactive (NOSir) elements in the brain of the Atlantic salmon was investigated by means of electron microscopy and confocal laser scanning microscopy. NOSir structures are present only in neuronal elements. In neuronal processes, strong NOS immunoreactivity was mainly localized within synaptic vesicles or seen as a den

Nitric oxide synthase in the brain of a teleost

The presence and distribution of the nitric oxide (NO) converting enzyme, NO synthase (NOS), was investigated in the brain of a teleost, the Atlantic salmon. Both NOS immunoreactive and NADPH diaphorase positive, non-neuronal and neuronal cell bodies, fibers and putative nerve terminals were identified throughout the brain. Even so, the staining was not identical in all regions. NO, synthesized by

Lars E O Svenssons drama i fyra akter.

Lars E O Svenssons kritik mot att Riksbanken inte har uppnått inflationsmålet har lett till en infekterad debatt mellan ledande ekonomer. Vår genomgång av hans kalkyler visar att de är bräckliga och missvisande, skriver ekonomiforskarna Lars Jonung och Fredrik N G Andersson.

Evolution of reproductive phenology in annual social insects competing for floral resources

Question: How does reproductive timing in annual social insects evolve under intraspecific exploitation competition and in response to a changing environment? The latter includes shifts in resource abundance, mortality, season length, and resource peak timing, factors often associated with climate change. Background: Climate and land use are changing. Evolutionary ecology must learn to predict how

Scalable synthesis of dispersible iron carbide (Fe3C) nanoparticles by 'nanocasting'

Metal carbides have shown great promise in a wide range of applications due to their unique catalytic, electrocatalytic and magnetic properties. However, the scalable production of dispersible metal carbide nanoparticles remains a challenge. Here, we report a simple and scalable route to dispersible iron carbide (Fe3C) nanoparticles. This uses MgO nanoparticles as a removable 'cast' to synthesize

Magnetic phase diagram of the quantum spin chain compound SrCo2V2O8 : A single-crystal neutron diffraction study

We explore magnetic order in the quantum spin chain compound SrCo2V2O8 up to 14.9 T and down to 50 mK, using single-crystal neutron diffraction. Upon cooling in zero-field, commensurate antiferromagnetic (C-AFM) order with modulation vector=(0, 0, 1) develops below T N≃5.0K. Applying an external magnetic field (H∥c axis) destabilizes this C-AFM order, leading to an order-disorder transition betwee

Effects of intervention on self-efficacy and text quality in elementary school students’ narrative writing

Aim: Self-efficacy for writing is an important motivational factor and considered to predict writing performance. Self-efficacy for narrative writing has been sparsely studied, and few studies focus on the effects of writing intervention on self-efficacy. Additionally, there is a lack of validated measures of self-efficacy for elementary school students. In a previous study, we found that a traine

Event-related potentials to visual processing of incongruities in negated and affirmative sentences

In spite of the fact that negation has been the focus of many studies, the way it is processed in human communication still eludes us. Previous studies of negation using event-related potentials (ERPs) have reported inconclusive results as to whether or not negation poses difficulties for processing. While some have found that negation is initially ignored and incongruities in negated sentences do

Trait anxiety and bystander motivation to defend victims of school bullying

Introduction: School-based bullying is an omnipresent problem, but is less frequent when bystanders are inclined to defend victims. This makes it important to focus on motivation to intervene in bullying. Methods: 202 students (Mage=16.44 years, 52% boys) from public Swedish high schools participated in a vignette experiment. Students were randomized to one of two vignettes (victim belonging to/no

Distribution of met‐enkephalin, leu‐enkephalin, substance P, neuropeptide Y, FMRFamide, and serotonin immunoreactivities in the optic tectum of the Atlantic salmon (Salmo salar L.)

The distribution of the neuropeptides methionine‐ and leucine‐enkephalins, substance P, FMRFamide, neuropeptide Y, and vasoactive intestinal peptide, as well as the biogenic amine serotonin was studied in the optic tectum of the Atlantic salmon by means of immunocytochemistry. Peroxidase‐antiperoxidase and indirect immunofluorescence methods were used to compare the differential laminar distributi

Enkephalin-immunoreactive cells in the mesencephalic tegmentum project to the optic tectum of the teleosts Salmo gairdneri and Salmo salar

Immunocytochemistry using antibodies against Met-enkephalin and Leu-enkephalin has demonstrated a group of large enkephalin-immunoreactive neurons in the nucleus of the rostral mesencephalic tegmentum (mRMT) of two teleost fish, Salmo gairdneri and Salmo salar. Injections of cobalt-lysine in the medial optic tectum retrogradely labeled the above group of tegmental neurons. Tegmental neurons were l

The Parapineal Organ of Teleosts

A parapineal organ was found to be present in 21 teleost fishes belonging to 20 different families, but was absent in poecilids and cyprinodontids. The parapineal organ was situated on the left side of the brain and sent a nerve tract to the left habenular nucleus, except in Gadus, where a “parapineal organ” appeared to send a nerve tract into the pineal stalk. The parapineal organ of adult Gaster

Antibodies against retinal photoreceptor‐specific proteins reveal axonal projections from the photosensory pineal organ in teleosts

With the aid of specific antisera to the retinal proteins S‐antigen and α‐transducin and to the rhodopsin apoprotein opsin, we have labeled various cell populations in the pineal organ, parapineal organ, habenular nucleus, and subcommissural organ in two teleost species: the rainbow trout and the European minnow. Although these proteins are associated with photoreceptor functions, not only photore

Substance P-like-immunoreactive neurons in the photosensory pineal organ of the rainbow trout, Salmo gairdneri Richardson (Teleostei)

Restricted numbers of substance P-like-immuno-reactive (SPL-IR) neurons were demonstrated in the photosensory pineal organ of the rainbow trout. The small parapineal organ of this teleost species receives a distinct SPL-IR innervation via the habenular nuclei, but displays no intrinsic SPL-IR neurons. Intrapineal SPL-IR neurons were located in the rostral portion of the pineal end-vesicle. Neurona

Serotonin and opsin immunoreactivities in the developing pineal organ of the three-spined stickleback, Gasterosteus aculeatus L.

5-hydroxytryptamine (5-HT, serotonin)- and opsin-immunoreactive sites were studied in the developing pineal complex of the stickleback, Gasterosteus aculeatus L., by use of light-microscopic indirect immunoperoxidase techniques. 5-HT immunoreactivity first occurs in the pineal organ at the age of 80 h after fertilization and appears to be localized in cells of the photoreceptor type. The outer seg