957 research outputs found
Evaluation of Cool Season Forage Combinations for White-Tailed Deer
Last updated: 6/1/200
Pinch Resonances in a Radio Frequency Driven SQUID Ring-Resonator System
In this paper we present experimental data on the frequency domain response
of a SQUID ring (a Josephson weak link enclosed by a thick superconducting
ring) coupled to a radio frequency (rf) tank circuit resonator. We show that
with the ring weakly hysteretic the resonance lineshape of this coupled system
can display opposed fold bifurcations that appear to touch (pinch off). We
demonstrate that for appropriate circuit parameters these pinch off lineshapes
exist as solutions of the non-linear equations of motion for the system.Comment: 9 pages, 8 figures, Uploaded as implementing a policy of arXiving old
paper
The METCRAX II Field Experiment: A Study of Downslope Windstorm-Type Flows in Arizona\u2019s Meteor Crater
The second Meteor Crater Experiment (METCRAX II) was conducted in October 2013 at Arizona\u2019s Meteor Crater. The experiment was designed to investigate nighttime downslope windstorm 12type flows that form regularly above the inner southwest sidewall of the 1.2-km diameter crater as a southwesterly mesoscale katabatic flow cascades over the crater rim. The objective of METCRAX II is to determine the causes of these strong, intermittent, and turbulent inflows that bring warm-air intrusions into the southwest part of the crater. This article provides an overview of the scientific goals of the experiment; summarizes the measurements, the crater topography, and the synoptic meteorology of the study period; and presents initial analysis results
Energy Down Conversion between Classical Electromagnetic Fields via a Quantum Mechanical SQUID Ring
We consider the interaction of a quantum mechanical SQUID ring with a
classical resonator (a parallel tank circuit). In our model we assume that
the evolution of the ring maintains its quantum mechanical nature, even though
the circuit to which it is coupled is treated classically. We show that when
the SQUID ring is driven by a classical monochromatic microwave source, energy
can be transferred between this input and the tank circuit, even when the
frequency ratio between them is very large. Essentially, these calculations
deal with the coupling between a single macroscopic quantum object (the SQUID
ring) and a classical circuit measurement device where due account is taken of
the non-perturbative behaviour of the ring and the concomitant non-linear
interaction of the ring with this device.Comment: 7 pages, 6 figure
Hydrogen sulfide protects renal grafts against prolonged cold ischemia-reperfusion injury via specific mitochondrial actions
This article has been accepted for publication and undergone full peer review but has not been
through the copyediting, typesetting, pagination and proofreading process, which may lead to
differences between this version and the Version of Record. Please cite this article as doi:
10.1111/ajt.14080
This article is protected by copyright. All rights reserved.Accepted manuscript online:
15 October 2016Ischemia-reperfusion injury (IRI) is unavoidably caused by loss and subsequent restoration of blood flow during organ procurement and prolonged IRI results in increased rates of delayed graft function and early graft loss. The endogenously produced gasotransmitter, hydrogen sulfide (H2 S), is a novel molecule that mitigates hypoxic tissue injury. The current study investigates the protective mitochondrial effects of H2 S during in vivo cold storage and subsequent renal transplantation (RTx) and in vitro cold hypoxic renal injury. Donor allografts from Brown Norway rats treated with University of Wisconsin (UW) solution + H2 S (150 μM NaSH) during prolonged (24-hour) cold (4°C) storage exhibited significantly (p1000-fold compared to similar levels of the non-specific H2 S donor, GYY4137 and also improved syngraft function and survival following prolonged cold storage compared to UW. H2 S treatment mitigates cold IRI-associated renal injury via mitochondrial actions and could represent a novel therapeutic strategy to minimize the detrimental clinical outcomes of prolonged cold IRI during RTx.This work was supported by grants from Physicians Services Incorporated and the Canadian
Urological Association (AS) and by a Frederick Banting and Charles Best Canada Graduate
Scholarships Doctoral Award from the Canadian Institutes of Health Research (IL). MW and
MEW would like to thank the Medical Research Council UK (MR/M022706/1) for their
generous research support. RT would like to acknowledge the Brian Ridge Scholarship for
support
Breast cancer risk in male twins: joint analyses of four twin cohorts in Denmark, Finland, Sweden and the United States
To test the hypothesis that in utero exposure to high levels of oestrogen increases the risk of male breast cancer, we followed 115 235 male twins for more than 3.5 million person-years at risk. We observed 11 cases of male breast cancer versus 16.16 expected based on national rates (standardized rate ratio 0.68, 95% confidence interval 0.34–1.22) and conclude that any adverse influence of in utero oestrogen exposure is likely to be small. © 2000 Cancer Research Campaig
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Development of a Balloon-Borne Stabilized Platform for Measuring Radiative Flux Profiles in the Atmospheric Boundary Layer
A stabilized platform has been developed to carry broadband short-wave and long-wave radiometric sensors on the tether line of a small tethered balloon that ascends through atmospheric depths of up to 1.5 km to obtain vertical profiles of radiative flux and flux divergence for evaluating atmospheric radiative transfer models. The Sky Platform was designed to keep the radiometers level despite unpredictable movements of the balloon and tether line occasioned by turbulence and wind shear. The automatic control loop drives motors, gears, and pulleys located on two of the vertices of the triangular frame to climb the harness lines to keep the platform level. Radiometric sensors, an electronic compass, and an on-board data acquisition system make up the remainder of the Sky Platform. Because knowledge of the dynamic response of the tether line-platform system is essential to properly close the automatic control loop on the Sky Platform, a Motion Sensing Platform (MSP) was developed to fly in place of the Sky Platform on the tether line to characterize the Sky Platform's operating environment. This unstabilized platform uses an array of nine solid-state linear accelerometers to measure the lateral and angular accelerations, velocities, and displacements that the Sky Platform will experience. This paper presents field performance tests of the Sky and Motion Sensing Platforms, as conducted at Richland, Washington, on February 17, 1993. The tests were performed primarily to characterize the stabilization system on the Sky Platform. Test flights were performed on this cold winter day from 1400 to 1800 Pacific Standard Time (PST). During this period, temperature profiles were near the dry adiabatic lapse rate. Flights were made through a jet wind speed profile having peak wind speeds of 7 m/s at a height of 100 m AGL. Wind directions were from the northwest. All flights were performed as continuous ascents, rather than ascending in discrete steps with halts at set altitudes
GYY4137, a slow-releasing hydrogen sulfide donor, ameliorates renal damage associated with chronic obstructive uropathy.
PURPOSE: Chronic obstructive uropathy can cause irreversible kidney injury, atrophy, and inflammation, which can ultimately lead to fibrosis. Epithelial-mesenchymal transition (EMT) is a key trigger of fibrosis and is caused by upregulation of transforming growth factor beta 1 (TGF-β1) and angiotensin II (ANGII). Hydrogen sulfide (H2S) is an endogenously produced gasotransmitter with cytoprotective properties. The present study aims to elucidate the effects of the slow-releasing H2S donor GYY4137 on chronic ureteral obstruction and evaluate potential mechanisms. MATERIALS AND METHODS: Following unilateral ureteral obstruction (UUO), male Lewis rats were given daily intraperitoneal (IP) administration of phosphate buffered saline (PBS) vehicle (UUO group) or PBS+200μmol/kg GYY4137 (UUO+GYY4137 group) for 30 days. Urine and serum samples were collected to determine physiological parameters of renal function and injury. Kidneys were removed on post-operative day 30 for evaluation of histopathology and protein expression. EMT in pig kidney epithelial cells (LLC-PK1) was induced with TGF-β1 and treated with GYY4137 to evaluate potential mechanisms via in vitro scratch wound assays. RESULTS: H2S treatment decreased serum creatinine and urine protein/creatinine excretion ratio following UUO. In addition, H2S mitigated cortical loss, inflammatory damage, and tubulointerstitial fibrosis. Tissues exhibited decreased expression of EMT markers upon H2S treatment. EMT progression in LLC-PK1 was alleviated upon in vitro administration of GYY4137. CONCLUSIONS: Our findings demonstrate, for the first time, the protective effects of H2S in chronic obstructive uropathy and may represent a potential therapeutic solution to ameliorate renal damage and improve clinical outcomes of urinary obstruction.This work was supported by a grant from the Lawson Health Research Foundation
Non-linear Multi-level Dynamics of a SQUID Ring-resonator System in the Hysteretic Regime
We consider the dynamical behavior of a strongly hysteretic SQUID ring coupled to a radio frequency resonator. By experiment we show that this system can display novel multiple level structures in its rf voltage-current characteristics which are solutions of the nonlinear equations of motion describing the system
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