863 research outputs found

    Construction and Assembly of a Hyperdrive Recording Implant

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    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

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    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

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    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

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    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.

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    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

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    We present deep (∼17 μ\sim 17~\muJy) 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

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    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

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    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

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    We present results from a high-sensitivity (60 μ\muJy), 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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