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Imbibition dynamics of nano-particulate ink-jet drops on micro-porous media
Ink-jet printing of nano-metallic colloidal fluids on to
porous media such as coated papers has become a viable
method to produce conductive tracks for low-cost,
disposable printed electronic devices. However, the
formation of well-defined and functional tracks on an
absorbing surface is controlled by the drop imbibition
dynamics in addition to the well-studied post-impact drop
spreading behavior.
This study represents the first investigation of the realtime
imbibition of ink-jet deposited nano-Cu colloid drops
on to coated paper substrates. In addition, the same ink was
deposited on to a non-porous polymer surface as a control
substrate. By using high-speed video imaging to capture the
deposition of ink-jet drops, the time-scales of drop
spreading and imbibition were quantified and compared
with model predictions. The influences of the coating pore
size on the bulk absorption rate and nano-Cu particle
distribution have also been studied
Optical Images and Source Catalog of AKARI North Ecliptic Pole Wide Survey Field
We present the source catalog and the properties of the , and
band images obtained to support the {\it AKARI} North Ecliptic Pole Wide
(NEP-Wide) survey. The NEP-Wide is an {\it AKARI} infrared imaging survey of
the north ecliptic pole covering a 5.8 deg area over 2.5 -- 6 \micron
wavelengths. The optical imaging data were obtained at the Maidanak Observatory
in Uzbekistan using the Seoul National University 4k 4k Camera on the
1.5m telescope. These images cover 4.9 deg where no deep optical imaging
data are available. Our , and band data reach the depths of
23.4, 23.1, and 22.3 mag (AB) at 5, respectively. The
source catalog contains 96,460 objects in the band, and the astrometric
accuracy is about 0.15\arcsec at 1 in each RA and Dec direction.
These photometric data will be useful for many studies including identification
of optical counterparts of the infrared sources detected by {\it AKARI},
analysis of their spectral energy distributions from optical through infrared,
and the selection of interesting objects to understand the obscured galaxy
evolution.Comment: 39 pages, 12 figure
Measuring Accuracy of Automated Parsing and Categorization Tools and Processes in Digital Investigations
This work presents a method for the measurement of the accuracy of evidential
artifact extraction and categorization tasks in digital forensic
investigations. Instead of focusing on the measurement of accuracy and errors
in the functions of digital forensic tools, this work proposes the application
of information retrieval measurement techniques that allow the incorporation of
errors introduced by tools and analysis processes. This method uses a `gold
standard' that is the collection of evidential objects determined by a digital
investigator from suspect data with an unknown ground truth. This work proposes
that the accuracy of tools and investigation processes can be evaluated
compared to the derived gold standard using common precision and recall values.
Two example case studies are presented showing the measurement of the accuracy
of automated analysis tools as compared to an in-depth analysis by an expert.
It is shown that such measurement can allow investigators to determine changes
in accuracy of their processes over time, and determine if such a change is
caused by their tools or knowledge.Comment: 17 pages, 2 appendices, 1 figure, 5th International Conference on
Digital Forensics and Cyber Crime; Digital Forensics and Cyber Crime, pp.
147-169, 201
N-(Benzothiazol-2-yl)butyramide
The title compound, C11H12N2OS, was synthesized from 2-aminobenzothiazole and butanoyl chloride in anhydrous acetone. In the crystal structure, molecules are linked by N—H⋯N and C—H⋯O hydrogen bonds and by C—H⋯π interactions
Potentiation of sensory responses in ventrobasal thalamus in vivo via selective modulation of mGlu1 receptors with a positive allosteric modulator.
Metabotropic glutamate subtype 1 (mGlu1) receptor is thought to play a role in synaptic responses in thalamic relay nuclei. The aim of this study was to evaluate the positive allosteric modulator (PAM) Ro67-4853 as a tool to modulate thalamic mGlu1 receptors on single thalamic neurones in vivo. Ro67-4853, applied by iontophoresis onto ventrobasal thalamus neurones of urethane-anaesthetised rats, selectively enhanced responses to the agonist (S)-3,5-dihydroxy-phenylglycine (DHPG), an effect consistent with mGlu1 potentiation. The PAM was also able to enhance maintained responses to 10 Hz trains of sensory stimulation of the vibrissae, but had little effect on responses to single sensory stimuli. Thus Ro67-4853 appears to be a highly selective tool that can be useful in investigating how mGlu1 receptor potentiation can alter neural processing in vivo. Our results show the importance of mGlu1 in sensory processing and attention mechanisms at the thalamic level and suggest that positive modulation of mGlu1 receptors might be a useful mechanism for enhancing cognitive and attentional processes
Conservative and disruptive modes of adolescent change in human brain functional connectivity
Adolescent changes in human brain function are not entirely understood. Here, we used multiecho functional MRI (fMRI) to measure developmental change in functional connectivity (FC) of resting-state oscillations between pairs of 330 cortical regions and 16 subcortical regions in 298 healthy adolescents scanned 520 times. Participants were aged 14 to 26 y and were scanned on 1 to 3 occasions at least 6 mo apart. We found 2 distinct modes of age-related change in FC: “conservative” and “disruptive.” Conservative development was characteristic of primary cortex, which was strongly connected at 14 y and became even more connected in the period from 14 to 26 y. Disruptive development was characteristic of association cortex and subcortical regions, where connectivity was remodeled: connections that were weak at 14 y became stronger during adolescence, and connections that were strong at 14 y became weaker. These modes of development were quantified using the maturational index (MI), estimated as Spearman’s correlation between edgewise baseline FC (at 14 y, FC14) and adolescent change in FC (ΔFC14−26), at each region. Disruptive systems (with negative MI) were activated by social cognition and autobiographical memory tasks in prior fMRI data and significantly colocated with prior maps of aerobic glycolysis (AG), AG-related gene expression, postnatal cortical surface expansion, and adolescent shrinkage of cortical thickness. The presence of these 2 modes of development was robust to numerous sensitivity analyses. We conclude that human brain organization is disrupted during adolescence by remodeling of FC between association cortical and subcortical areas
Responses of primate LGN cells to moving stimuli involve a constant background modulation by feedback from area MT
The feedback connections from the cortical motion area middle temporal (MT), to layer 6 of the primary visual cortex (V1), have the capacity to drive a cascaded feedback influence from the layer 6 cortico-geniculate cells back to the lateral geniculate nucleus (LGN) relay cells. This introduces the possibility of a re-entrant motion signal affecting the relay of the retinal input through the LGN to the visual cortex. The question is whether the response of LGN cells to moving stimuli involves a component derived from this feedback. By producing a reversible focal pharmacological block of the activity of an MT direction column we show the presence of such an influence from MT on the responses of magno, parvo and koniocellular cells in the macaque LGN. The pattern of effect in the LGN reflects the direction bias of the MT location inactivated. This suggests a moving stimulus is captured by iterative interactions in the circuit formed by visual cortical areas and visual thalamus
Corrigendum: Mutualistic Coupling Between Vocabulary and Reasoning Supports Cognitive Development During Late Adolescence and Early Adulthood
Correction to: Kievit, R. A., Lindenberger, U., Goodyer, I. M., Jones, P. B., Fonagy, P., Bullmore, E. T., the Neuroscience in Psychiatry Network, & Dolan, R. J. (2017). Mutualistic coupling between vocabulary and reasoning supports cognitive development during late adolescence and early adulthood. Psychological Science, 28, 1419–1431. doi:10.1177/095679761771078
Cortical oscillatory dynamics and benzodiazepine-site modulation of tonic inhibition in fast spiking interneurons
Tonic conductance mediated by extrasynaptic GABAA receptors has been implicated in the modulation of network oscillatory activity. Using an in vitro brain slice to produce oscillatory activity and a kinetic model of GABAA receptor dynamics, we show that changes in tonic inhibitory input to fast spiking interneurons underlie benzodiazepine-site mediated modulation of neuronal network synchrony in rat primary motor cortex. We found that low concentrations (10 nM) of the benzodiazepine site agonist, zolpidem, reduced the power of pharmacologically-induced beta-frequency (15-30 Hz) oscillatory activity. By contrast, higher doses augmented beta power. Application of the antagonist, flumazenil, also increased beta power suggesting endogenous modulation of the benzodiazepine binding site. Voltage-clamp experiments revealed that pharmacologically-induced rhythmic inhibitory postsynaptic currents were reduced by 10 nM zolpidem, suggesting an action on inhibitory interneurons. Further voltage-clamp studies of fast spiking cells showed that 10 nM zolpidem augmented a tonic inhibitory GABAA receptor mediated current in fast spiking cells whilst higher concentrations of zolpidem reduced the tonic current. A kinetic model of zolpidem-sensitive GABAA receptors suggested that incubation with 10 nM zolpidem resulted in a high proportion of GABAA receptors locked in a kinetically slow desensitized state whilst 30 nM zolpidem favoured rapid transition into and out of desensitized states. This was confirmed experimentally using a challenge with saturating concentrations of GABA. Selective modulation of an interneuron-specific tonic current may underlie the reversal of cognitive and motor deficits afforded by low-dose zolpidem in neuropathological states
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