734 research outputs found

    Effect of Temperature Change on Saccular Nerve Fiber Response in Goldfish

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    A Standardized Measure of Motility

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    In any survey of the fundamental capacities of motor control the factor of speed of simple movement is obvious as one of the basic essentials which underlie all the developed complexities of movement. This fundamental capacity for speed in a simple repeated movement we call motility, and the motion selected is an easy movement of the forearm in which the finger taps a telegraph key. This type of movement is selected because it is one of the most rapid of the voluntary movements; it is clearly developed, is very simple, and requires no learning. It is assumed that the ability shown in this movement is, in general, indicative of corresponding ability in other parts of the body

    Baseline performance and emissions data for a single-cylinder, direct-injected diesel engine

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    Comprehensive fuel consumption, mean effective cylinder pressure, and emission test results for a supercharged, single-cylinder, direct-injected, four-stroke-cycle, diesel test engine are documented. Inlet air-to-exhaust pressure ratios were varied from 1.25 to 3.35 in order to establish the potential effects of turbocharging techniques on engine performance. Inlet air temperatures and pressures were adjusted from 34 to 107 C and from 193 to 414 kPa to determine the effects on engine performance and emissions. Engine output ranged from 300 to 2100 kPa (brake mean effective pressure) in the speed range of 1000 to 3000 rpm. Gaseous and particulate emission rates were measured. Real-time values of engine friction and pumping loop losses were measured independently and compared with motored engine values

    Studies of thermionic materials for space power applications informal monthly report, oct. 1 - oct. 31, 1963

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    Thermionic space power material - isostatic pressing, vapor deposited tungsten, high temperature properties, cesium thermionic cell life testing, and irradiation studie

    Evaluating Exposure of Northern Fur Seals, Callorhinus Ursinus, to Microplastic Pollution Through Fecal Analysis

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    Environmental microplastics are widely documented in marine life and bioaccumulation may present risks to marine predators. Investigations of microplastics in marine mammals are increasing, though none have examined animals routinely consumed by humans. Here, we investigate microplastic exposure in the northern fur seal (Callorhinus ursinus), a species consumed by humans, using fecal material. We examined 44 feces (scat) at sites encompassing the seals\u27 eastern Pacific range. Multiple contamination control measures were implemented, including field and laboratory controls. Fragments were the most common microplastic recovered, in 55% (24/44) of scat and no controls (range 1 to 86 fragments/scat, mean 16.6, sd 19.1). Microplastic fibers were recovered from 41% of scats (18/44), though some controls contained fibers confounding fiber results. Fecal analysis documented northern fur seal exposure to microplastics throughout their eastern Pacific range. © 201

    Investigating the Impact of Supercritical Fluid Properties on the Turbulence Physics of the Round Turbulent Jet

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    Supercritical Carbon Dioxide (sCO2) is a promising working fluid for many applications across a wide range of industries. One such example is in advanced cycles, including those for power generation (e.g., Brayton cycle), because of increased power density. While research on experimental engineering has revealed interesting physical aspects of supercritical fluids, open questions remain about the fundamental physics of these flows. In this investigation, we study sCO2jets to gain a better understanding of the underlying physics and the influence of non-ideal variations in the physical properties of supercritical fluids. We study the impact of a cubic equation of state on turbulent flow physics using PeleC, a first-principles simulation code that leverages second order finite volume methods with adaptive mesh refinement. We implement the Piecewise Parabolic Method with a standard second order Runge-Kutta method to approximate our solutions. The system of partial differential equations is closed using the Soave-Redlich-Kwong equation of state. Special attention is paid to the stability of coupling the cubic equation of state with the Navier-Stokes equations. Simulations for the sCO2turbulent round jet are performed at 330 K and 10 MPa, conditions that are above the critical point of 304.25 K and 7.39 MPa, where new insight is needed for engineering design. We then examine velocity and Reynolds stress profiles at different downstream locations and contrast these with established theory. We explore cases with differing jet and ambient fluid temperatures to study the effect of thermal property variation in supercritical fluids

    Programmable Spectral Source and Design Tool for 3D Imaging Using Complementary Bandpass Filters

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    An endoscopic illumination system for illuminating a subject for stereoscopic image capture, includes a light source which outputs light; a first complementary multiband bandpass filter (CMBF) and a second CMBF, the first and second CMBFs being situated in first and second light paths, respectively, where the first CMBF and the second CMBF filter the light incident thereupon to output filtered light; and a camera which captures video images of the subject and generates corresponding video information, the camera receiving light reflected from the subject and passing through a pupil CMBF pair and a detection lens. The pupil CMBF includes a first pupil CMBF and a second pupil CMBF, the first pupil CMBF being identical to the first CMBF and the second pupil CMBF being identical to the second CMBF, and the detection lens includes one unpartitioned section that covers both the first pupil CMBF and the second pupil CMBF

    Propagation of Pi2 pulsations through the braking region in global MHD simulations

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    We investigate the propagation of Pi2 period pulsations from their origin in the plasma sheet through the braking region, the region where the fast flows are slowed as they approach the inner edge of the plasma sheet. Our approach is to use both the University of California, Los Angeles (UCLA) and Lyonâ Fedderâ Mobarry (LFM) global magnetohydrodynamic (MHD) computer codes to simulate the Earth’s magnetosphere during a substorm that occurred on 14 September 2004 when Pi2 pulsations were observed. We use two different MHD models in order to test the robustness of our conclusions about Pi2. The simulations are then compared with groundâ based and satellite data. We find that the propagation of the pulsations in the simulations, especially through the braking region, depends strongly on the ionospheric models used at the inner boundary of the MHD models. With respect to typical observed values, the modeled conductances are high in the UCLA model and low in the LFM model. The different conductances affect the flows, producing stronger line tying that slows the flow in the braking region more in the UCLA model than in the LFM model. Therefore, perturbations are able to propagate much more freely into the inner magnetosphere in the LFM results. However, in both models Pi2 period perturbations travel with the dipolarization front (DF) that forms at the earthward edge of the flow channel, but as the DF slows in the braking region, â 8â ¤xâ ¤â 6 RE, the Pi2 period perturbations begin to travel ahead of it into the inner magnetosphere. This indicates that the flow channels generate compressional waves with periods that fall within the Pi2 range and that, as the flows themselves are stopped in the braking region, the compressional wave continues to propagate into the inner magnetosphere.Key PointsPi2 travel with DFs until the DFs slow in the braking region and the Pi2 begin to run ahead of themIonospheric parameters strongly affect how Pi2 are able to propagateBoth the UCLA and LFM models show similar results for Pi2 propagation outside of â ¼â 7 REPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134917/1/jgra52317_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134917/2/jgra52317.pd

    CanWalk: a feasibility study with embedded randomised controlled trial pilot of a walking intervention for people with recurrent or metastatic cancer.

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    Objectives: Walking is an adaptable, inexpensive and accessible form of physical activity. However its impact on quality of life and symptom severity in people with advanced cancer is unknown. This study aimed to assess the feasibility and acceptability of a randomised controlled trial (RCT) of a community-based walking intervention to enhance quality of life (QoL) in people with recurrent/metastatic cancer. Design: We used a mixed-methods design comprising a two-centre RCT and nested qualitative interviews. Participants: Patients with advanced breast, prostate, gynaecological or haematological cancers randomised 1:1 between intervention and usual care. Intervention: The intervention comprised Macmillan’s ‘Move More’ information, a short motivational interview with a recommendation to walk for at least 30 minutes on alternate days and attend a volunteer-led group walk weekly. Outcomes: we assessed feasibility and acceptability of the intervention and RCT by evaluating study processes (rates of recruitment, consent, retention, adherence and adverse events), and using end of study questionnaires and qualitative interviews. Patient reported outcome measures (PROMS) assessing quality of life (QoL), activity, fatigue, mood and self-efficacy were completed at baseline and 6, 12 and 24 weeks. Results: We recruited 42 (38%) of eligible participants. Recruitment was lower than anticipated (goal n=60), the most commonly reported reason being unable to commit to walking groups (n=19). Randomisation procedures worked well with groups evenly matched for age, sex and activity. By week 24, there was a 45% attrition rate. Most PROMs whilst acceptable were not sensitive to change and did not capture key benefits. Conclusions: The intervention was acceptable, well tolerated and the study design was judged acceptable and feasible. Results are encouraging and demonstrate that exercise was popular and conveyed benefit to participants. Consequently, an effectiveness RCT is warranted, with some modifications to the intervention to include greater tailoring and more appropriate PROMs selected.</p
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