181 research outputs found
Formalization of Transform Methods using HOL Light
Transform methods, like Laplace and Fourier, are frequently used for
analyzing the dynamical behaviour of engineering and physical systems, based on
their transfer function, and frequency response or the solutions of their
corresponding differential equations. In this paper, we present an ongoing
project, which focuses on the higher-order logic formalization of transform
methods using HOL Light theorem prover. In particular, we present the
motivation of the formalization, which is followed by the related work. Next,
we present the task completed so far while highlighting some of the challenges
faced during the formalization. Finally, we present a roadmap to achieve our
objectives, the current status and the future goals for this project.Comment: 15 Pages, CICM 201
The relationships between neurons containing dopamine and nitric oxide synthase in the ventral tegmental area.
Ventral tegmental area (VTA) is a heterogeneous group of dopaminergic cells which contains interfascicular (IF), parabrachial (PBP) and rostral linear (RLi) nuclei. Neurons of this area are involved in the regulation of motor and motivational aspects of behavior and reveal high neuronal plasticity. Among many various neurotransmitters and neuromodulators, nitric oxide (NO) is localized in this region. In the present study, we investigated morphology and distribution of nitric oxide synthase (NOS)-positive neurons in VTA and their colocalization with dopaminergic neurons. The study was performed on six adult Wistar rats. After perfusional fixation, the brains were cut, immunostained for tyrosine hydroxylase (TH) and NOS and studied by confocal laser microscopy. In each of the three studied nuclei of VTA we investigated three different neuronal populations. Numerous TH-immunoreactive (TH-ir) and NOS-immunoreactive (NOS-ir) neurons are present in the studied region. Among them, a considerable number showed coexistence of both neurotransmitters. The populations of TH-ir and NOS-ir neurons interact with each other as manifested by the presence of NOS-ir endings on TH-ir neurons and vice versa. Taking the above into account, it may be suspected that NO is involved in the modulation of dopaminergic transmission
Predominant expression of Alzheimer’s disease-associated BIN1 in mature oligodendrocytes and localization to white matter tracts
BIN1 is not expressed in human brain microglial cells. (A) Immunohistochemical staining of adjacent sections of normal human brain cortex with antibodies against BIN1 or Iba1 reveals that BIN1 immunoreactive cells that are morphologically distinct from microglia. The boxed region is shown at a higher magnification on the right. (B) Single and two-color immunostaining of the human brain using antibodies against BIN1 and CD45 reveals that perivenular CD45-positive cells of the hematopoietic lineage do not express BIN1. (TIFF 4392 kb
Minocycline but not valproic acid influence the density of NogoA-immunoreactive neurons in the hilus of the dentate gyrus of the rats subjected to intracerebral haematoma
Intracerebral haemorrhage is a devastating neurological disease with high mortality rate and poor prognosis. The most prominent manifestation of the disease arethe movement disorders, but many patients also suffer from cognitive impairment. Taking into account vulnerability of the neurons located within the hilus of the dentate gyrus (HDG) to many brain insults we decided to study the effectof experimentally induced intracerebral haematoma on density of neurons expressing NogoA protein in HDG. In addition, we studied how administration of valproic acid and minocycline, the two drugs generally believed to be neuroprotective agents, influences the density of these neurons. Our study revealed that 4 weeks after intracerebral haematoma induction, minocycline and valproic acid treatment increased the densities of NogoA-ir neurons in the hilus of contralateral dentate gyrus once the data were compared to ipsilateral hemispheres within the same group. The analysis of contralateral hemisphere data, however, revealed increased densities of NogoA-positive neurons in haematoma and valproic acidtreated animals when compared to contralateral hemispheres of control animals.The administration of minocycline was, however, able to alleviate this increase.These changes may influence the haematoma-induced reorganisation of neuronal circuitries in the dentate gyrus
The immunoreactivity of c-Fos, NGF and its receptor TrkA after open-field exposure in the central and medial nuclei of the rat amygdala
The amygdala is a critical component of the neuroanatomical stress circuit. It
plays a role in the generation of responses to emotional stimuli. The central
(CeA) and medial (MeA) amygdaloid nuclei are implicated in activation of the
hypothalamic-pituitary-adrenocortical (HPA) axis.
The immunoreactivity (-ir) of c-Fos, NGF and its receptor, TrkA, following acute
and chronic open-field stress were studied in the CeA and MeA nuclei of the
amygdala. The material consisted of 21 male adult rats divided into three groups:
non-stressed (control) animals, rats exposed to acute (once only lasting 15 min)
and chronic (15 min daily over 21 days) aversive stimulation (open-field exposure).
The brains were stained with the use of immunohistochemical methods
for c-Fos, NGF or TrkA.
In the control rats c-Fos-, TrkA- and NGF-ir cells were observed in the nuclei
studied, but the quantity varied, being moderate or high (immunoreactive to
TrkA and NGF) or low (immunoreactive to c-Fos).
In the animals exposed to acute open-field stress the number of c-Fos-ir, NGF-ir
and TrkA-ir cells in the nuclei under examination was differentiated but higher
than that in the control animals.
In the animals exposed to chronic open-field stress the number of c-Fos-ir cells
in the nuclei studied was similar and was smaller than those in animals exposed
to acute stress. The number of TrkA-ir neurons was also lower in comparison to
that in animals exposed to acute stress. However, no significant differences in
the number of NGF-ir cells were observed between the groups exposed to acute
and chronic stress.
Diverse expression of c-Fos protein following both acute and chronic stress stimulation
may prove the functional heterogeneity of the amygdaloid nuclei investigated.
The decrease observed in both c-Fos- and TrkA-ir in MeA (only TrkA in
CeA) of animals exposed to chronic stress may indicate the phenomenon of
habituation
Fluoride alters type I collagen expression in the early stages of odontogenesis
Fluoride alters the expression and post-translational modifications of extracellular
matrix proteins in dentin. The aim of our study was to determine the effects
of fluoride on type I collagen expression during the early stages of tooth germ
development in rats. Pregnant dams were divided into three groups and fed
a standard diet. From the fifth day of pregnancy the three groups received tap
water with, respectively, trace amounts of fluoride (C), a low fluoride concentration
(FL) or and a high fluoride concentration (FH). Changes in type I collagen
expression and distribution were evaluated. The expression of type I collagen
was restricted to the extracellular spaces of cells of mesenchymal origin. In the
youngest animals the most intense immunoreactivity for type I collagen was
detected in predentin of the FL group. Although the intensity of immunostaining
increased in proportion to the age of the animals, the largest increase in the
groups investigated was detected in the FL group. We concluded that a low
concentration of fluoride can act as a stimulator of type I collagen deposition in
the extracellular matrix of dentin, while high concentrations of fluoride have an
opposite effect, acting as an inhibitor of type I collagen formation in dentin
The LAGUNA design study- towards giant liquid based underground detectors for neutrino physics and astrophysics and proton decay searches
The feasibility of a next generation neutrino observatory in Europe is being
considered within the LAGUNA design study. To accommodate giant neutrino
detectors and shield them from cosmic rays, a new very large underground
infrastructure is required. Seven potential candidate sites in different parts
of Europe and at several distances from CERN are being studied: Boulby (UK),
Canfranc (Spain), Fr\'ejus (France/Italy), Pyh\"asalmi (Finland),
Polkowice-Sieroszowice (Poland), Slanic (Romania) and Umbria (Italy). The
design study aims at the comprehensive and coordinated technical assessment of
each site, at a coherent cost estimation, and at a prioritization of the sites
within the summer 2010.Comment: 5 pages, contribution to the Workshop "European Strategy for Future
Neutrino Physics", CERN, Oct. 200
Changes in NGF/c-Fos colocalization in specific limbic structures of juvenile and aged rats after open field stimulation
Changes in NGF release during stressful events have been associated with the
activation of neurons expressing NGF receptors. This study examined the influence
of acute stress-induced stimulation on NGF/c-Fos colocalization in the
following limbic regions: the paraventricular (PV) nucleus of the hypothalamus,
medial (MeA) nucleus of the amygdala, and CA3 hippocampus. Juvenile
(P21) and aged rats (P360) were exposed to a 15-minute acute open field
(OF) test. Double immunofluorescence staining, used to detect NGF-ir and
c-Fos-ir cells, revealed a higher percentage of NGF/c-Fos-ir neurons in the P21
control group than in the P360 control group. Under OF acute stimulation,
a statistically significant (p < 0.05) increase of NGF/c-Fos level in CA3 of juvenile
animals and in PV and CA3 of the aged rats was observed. These observations
indicate that the investigated structures in both age groups show a different
response to acute OF stimulation. Acute OF affects the levels of NGF/c-Fos
more significantly in aged rats
Free Asynchronous Professional Development By, From, and For Instructional Designers: How Informal Learning Opportunities Shape Our Professional Learning and Design Practices
Instructional designers (IDs) need to maintain an understanding of the current trends and issues within the field. Pursuing professional learning informally supports IDs’ effort to keep up with current trends and issues because it is not restricted by curriculum and time. Professional development (PD) offered by Professional Development for Instructional Designers (PD4IDs) learning group can address issues related to geographical and funding limitations. This application paper presents the coordination of PD based on the conceptual framework (e.g., Community of Practice and Social Network Knowledge Construction) and reflections of several PD4IDs members with various roles. The reflections indicate the benefits of participating in PD for shaping IDs’ professional learning and practices. Discussion and implications for IDs intending to pursue non-traditional PD are also presented
Apoptosis in the course of experimetal intracerebral haemorrhage in the rat
Intracerebral haematoma was produced in 25 adult rats by infusion of 100 µl of
autologous blood into the striatum. The animals’ brains were removed at 1, 3,
7, 14 and 21 days after production of the haematoma. The TUNEL method was
used to detect DNA fragmentation and TUNEL-positive cells were qualified.
TUNEL-positive cells were already found on the first day of observation and
were present for three weeks after haematoma production.
These results provide evidence that programmed cell death is associated with
intracerebral haemorrhage
- …
