863 research outputs found
Construction and Assembly of a Hyperdrive Recording Implant
The ability to record neural activity from multiple brain areas is crucial for the understanding of how different areas of the brain function or interact. This poster will cover instructions on how to construct and assemble a hyperdrive recording implant that bilaterally targets the ACC and the hippocampus. Intriguingly, the design of the hyperdrive recording implant is flexible and can be constructed to target other brain areas. The implant consists of 32 twisted bundles of tetrodes with a total of 128 individual recording wires which are controlled by movable ‘drivers’ (Gray et al., 1995; McNaughton et al., 1983). All 128 recording wires are then connected to an electrode interface board that takes information from the brain and transfers it to online available open-source acquisition software platform running. Using this implant with targeted tetrodes, we are able to look at the neuronal waveforms of individual neurons or the population-level responses in specific brain areas
Geometry of Discrete Quantum Computing
Conventional quantum computing entails a geometry based on the description of
an n-qubit state using 2^{n} infinite precision complex numbers denoting a
vector in a Hilbert space. Such numbers are in general uncomputable using any
real-world resources, and, if we have the idea of physical law as some kind of
computational algorithm of the universe, we would be compelled to alter our
descriptions of physics to be consistent with computable numbers. Our purpose
here is to examine the geometric implications of using finite fields Fp and
finite complexified fields Fp^2 (based on primes p congruent to 3 mod{4}) as
the basis for computations in a theory of discrete quantum computing, which
would therefore become a computable theory. Because the states of a discrete
n-qubit system are in principle enumerable, we are able to determine the
proportions of entangled and unentangled states. In particular, we extend the
Hopf fibration that defines the irreducible state space of conventional
continuous n-qubit theories (which is the complex projective space CP{2^{n}-1})
to an analogous discrete geometry in which the Hopf circle for any n is found
to be a discrete set of p+1 points. The tally of unit-length n-qubit states is
given, and reduced via the generalized Hopf fibration to DCP{2^{n}-1}, the
discrete analog of the complex projective space, which has p^{2^{n}-1}
(p-1)\prod_{k=1}^{n-1} (p^{2^{k}}+1) irreducible states. Using a measure of
entanglement, the purity, we explore the entanglement features of discrete
quantum states and find that the n-qubit states based on the complexified field
Fp^2 have p^{n} (p-1)^{n} unentangled states (the product of the tally for a
single qubit) with purity 1, and they have p^{n+1}(p-1)(p+1)^{n-1} maximally
entangled states with purity zero.Comment: 24 page
Measuring Energy Expenditure and Heart Rate during Maximum Aerobic Testing with the Apple Watch Series 7
Introduction: Wrist-worn devices such as the Apple Watch have emerged as technology for tracking physical activity. The aim of this research study is to analyze the Apple Watch Series 7 (AW7) with measurements of the maximum heart rate (MHR) and maximum energy expenditure (MEE) during a maximal aerobic capacity test on the treadmill. AW7 measurements will be compared to the Polar Heart Rate Monitor (Polar) and the PARVO Metabolic Cart (PARVO). Methods: 22 healthy and active subjects (mean ± SD: age 23.8 ± 4.0 years; BMI 23.0 ± 5.9 kg/m2 ) volunteered for the study. The subjects confirmed their activity, health status, and were measured for body composition and aerobic capacity. Results: No significant difference was found in MEE between PARVO (109.6 ± 41.7 kcal) and AW7 (98.7 ± 24.3 kcal) conditions; t(21)=1.5, p = 0.153. In addition, there was no significant difference in MHR between PARVO (186.2 ± 16.2 BPM) and AW7 (189.3 ± 8.5 BPM) conditions; t(21)=-0.9, p = 0.379. Conclusions: The main findings of this study show that the MEE as well as the MHR between the AW7 compared to the PARVO are not different
Next Generation Protocol: Innovating a Resilient Future
Conventional practices do not account for product life beyond end-of-sale – these practices are not sustainable. We have developed an end-of-life protocol that includes a metric that we call the Recovery Rating. The objectives of this Next Generation Protocol, beyond supporting the United Nations’ Sustainable Development Goals, are to encourage the production of goods designed for recovery and to promote the collaboration between consumers, the public, and the private sector to recover goods at their end-of-life. The Recovery Rating that we propose evaluates and quantifies recovery potential of products. The Recovery Rating, which is normed against embodied energy from the Cambridge Engineering Selector by Granta Design, accounts for different tiers of recovery: product, component, and material, and different recovery methods at each tier and material family. We will present the results of our Next Generation Protocol using three case studies: 1) disposal, single use PET bottle, 2) Nalgene® reusable bottle, and 3) vacuum insulated, reusable metal bottle. The findings indicate the Next Generation Protocol produces a viable Recovery Rating for the material tier. We will also present survey data on potential user reactions to symbolic, numerical, and graphical versions of the Recovery Rating. The Recovery Ratings for the product and component tiers require considerations that have yet to be accounted for, such as number of uses and production/processing methods, which we present for future recommendations
Insulin and GLP-1 infusions demonstrate the onset of adipose-specific insulin resistance in a large fasting mammal: potential glucogenic role for GLP-1.
Prolonged food deprivation increases lipid oxidation and utilization, which may contribute to the onset of the insulin resistance associated with fasting. Because insulin resistance promotes the preservation of glucose and oxidation of fat, it has been suggested to be an adaptive response to food deprivation. However, fasting mammals exhibit hypoinsulinemia, suggesting that the insulin resistance-like conditions they experience may actually result from reduced pancreatic sensitivity to glucose/capacity to secrete insulin. To determine whether fasting results in insulin resistance or in pancreatic dysfunction, we infused early- and late-fasted seals (naturally adapted to prolonged fasting) with insulin (0.065 U/kg), and a separate group of late-fasted seals with low (10 pM/kg) or high (100 pM/kg) dosages of glucagon-like peptide-1 (GLP-1) immediately following a glucose bolus (0.5g/kg), and measured the systemic and cellular responses. Because GLP-1 facilitates glucose-stimulated insulin secretion, these infusions provide a method to assess pancreatic insulin-secreting capacity. Insulin infusions increased the phosphorylation of insulin receptor and Akt in adipose and muscle of early and late fasted seals; however the timing of the signaling response was blunted in adipose of late fasted seals. Despite the dose-dependent increases in insulin and increased glucose clearance (high dose), both GLP-1 dosages produced increases in plasma cortisol and glucagon, which may have contributed to the glucogenic role of GLP-1. Results suggest that fasting induces adipose-specific insulin resistance in elephant seal pups, while maintaining skeletal muscle insulin sensitivity, and therefore suggests that the onset of insulin resistance in fasting mammals is an evolved response to cope with prolonged food deprivation
The Gould's Belt Very Large Array Survey II: The Serpens region
We present deep (Jy) radio continuum observations of the Serpens
molecular cloud, the Serpens south cluster, and the W40 region obtained using
the Very Large Array in its A configuration. We detect a total of 146 sources,
29 of which are young stellar objects (YSOs), 2 are BV stars and 5 more are
associated with phenomena related to YSOs. Based on their radio variability and
spectral index, we propose that about 16 of the remaining 110 unclassified
sources are also YSOs. For approximately 65% of the known YSOs detected here as
radio sources, the emission is most likely non-thermal, and related to stellar
coronal activity. As also recently observed in Ophiuchus, our sample of YSOs
with X-ray counterparts lies below the fiducial G\"udel & Benz relation.
Finally, we analyze the proper motions of 9 sources in the W40 region. This
allows us to better constrain the membership of the radio sources in the
region.Comment: Accepted in The Astrophysical Journa
The Gould's Belt Distances Survey (GOBELINS). V. Distances and Kinematics of the Perseus molecular cloud
We derive the distance and structure of the Perseus molecular cloud by
combining trigonometric parallaxes from Very Long Baseline Array (VLBA)
observations, taken as part of the GOBELINS survey, and Gaia Data Release 2.
Based on our VLBA astrometry, we obtain a distance of 321+/-10 pc for IC 348.
This is fully consistent with the mean distance of 320+/-26 measured by Gaia.
The VLBA observations toward NGC 1333 are insufficient to claim a successful
distance measurement to this cluster. Gaia parallaxes, on the other hand, yield
a mean distance of 293+/-22 pc. Hence, the distance along the line of sight
between the eastern and western edges of the cloud is ~30 pc, which is
significantly smaller than previously inferred. We use Gaia proper motions and
published radial velocities to derive the spatial velocities of a selected
sample of stars. The average velocity vectors with respect to the LSR are
(u,v,w) = (-6.1+/-1.6, 6.8+/-1.1, -0.9+/-1.2) and (-6.4+/-1.0, 2.1+/-1.4,
-2.4+/-1.0) km/s for IC 348 and NGC 1333, respectively. Finally, our analysis
of the kinematics of the stars has shown that there is no clear evidence of
expansion, contraction, or rotational motions within the clusters.Comment: Accepted for publication in Ap
Topological Inflation with Multiple Winding
We analyze the core dynamics of critically coupled, superheavy gauge vortices
in the (2+1) dimensional Einstein-Abelian-Higgs system. By numerically solving
the Eistein and field equations for various values of the symmetry breaking
scale, we identify the regime in which static solutions cease to exist and
topological inflation begins. We explicitly include the topological winding of
the vortices into the calculation and extract the dependence on the winding of
the critical scale separating the static and inflating regimes. Extrapolation
of our results suggests that topological inflation might occur within high
winding strings formed at the Grand Unified scale.Comment: 13 pages, 4 figures, RevTe
The Gould's Belt Very Large Array Survey III. The Orion region
We present results from a high-sensitivity (60 Jy), large-scale (2.26
square degree) survey obtained with the Karl G. Jansky Very Large Array as part
of the Gould's Belt Survey program. We detected 374 and 354 sources at 4.5 and
7.5 GHz, respectively. Of these, 148 are associated with previously known Young
Stellar Objects (YSOs). Another 86 sources previously unclassified at either
optical or infrared wavelengths exhibit radio properties that are consistent
with those of young stars. The overall properties of our sources at radio
wavelengths such as their variability and radio to X-ray luminosity relation
are consistent with previous results from the Gould's Belt Survey. Our
detections provide target lists for followup VLBA radio observations to
determine their distances as YSOs are located in regions of high nebulosity and
extinction, making it difficult to measure optical parallaxes.Comment: Accepted for publication in ApJ; 51 pages, 15 figures, 5 table
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