3,648 research outputs found
Nitric oxide donation lowers blood pressure in adrenocorticotrophic hormone-induced hypertensive rats.
Adrenocorticotrophic hormone (ACTH) elevates systolic blood pressure (SBP) and lowers plasma reactive nitrogen intermediates in rats. We assessed the ability of NO donation from isosorbide dinitrate (ISDN) to prevent or reverse the hypertension caused by ACTH. In the prevention study, male Sprague Dawley rats were treated with ACTH (0.2 mg/kg/day) or saline control for 8 days, with either concurrent ISDN (100 mg/kg/day) via the drinking water or water alone. Animals receiving ISDN via the drinking water were provided with nitrate-free water for 8 hours every day. In the reversal study ISDN (100 mg/kg) or vehicle was given as a single oral dose on day 8. SBP was measured daily by the indirect tail-cuff method in conscious, restrained rats. ACTH caused a significant increase in SBP compared with saline (P < 0.0015). In the prevention study, chronic administration of ISDN (100 mg/kg/day) did not affect the SBP in either group. In the reversal study, ISDN significantly lowered SBP in ACTH-treated rats at 1 and 2.5 hours (132 +/- 3 mmHg (1 h) and 131 +/- 2 mmHg (2.5 h) versus 143 +/- 3 mmHg (0 h), P < 0.002), but not to control levels. It had no effect in control (saline treated) rats. In conclusion, the lowering of SBP by NO donation is consistent with the notion that ACTH-induced hypertension involves an impaired bioavailability or action of NO in vivo
Lecture capture: Early lessons learned and experiences shared
Lecture capture has been on the minds of university level teachers for some time. The ability to record teaching sessions for delivery online has a number of potential impacts, not all of them positive. The technology now exists to make it feasible and relatively affordable to deliver entire lectures online. But should we do it just because we can? This article aims to share our experiences in recording a series of organic chemistry lectures, and the findings of the evaluation that followed
INTSABA: A Mountain Home
The quality of the work in this book is all that was expected and more. This is the beginning of a journey that will impact all eSwatini. The Architecture School at Andrews University will remain a significant companion on this wonderful journey. We consider these children as Hope Seekers and our coffee table book about them shows the courage and ingenuity they display as they strive to survive. We are indeed all ‘hope seekers,’ except that we have options and they don’t. We praise God that there is now an open window to bring real hope to a population of children who need it most.https://digitalcommons.andrews.edu/books/1138/thumbnail.jp
SN2013fs and SN2013fr: Exploring the circumstellar-material diversity in Type II supernovae
We present photometry and spectroscopy of SN2013fs and SN2013fr in the first
100 days post-explosion. Both objects showed transient, relatively narrow
H emission lines characteristic of SNeIIn, but later resembled normal
SNeII-P or SNeII-L, indicative of fleeting interaction with circumstellar
material (CSM). SN2013fs was discovered within 8hr of explosion. Its light
curve exhibits a plateau, with spectra revealing strong CSM interaction at
early times. It is a less luminous version of the transitional SNIIn PTF11iqb,
further demonstrating a continuum of CSM interaction intensity between SNeII-P
and IIn. It requires dense CSM within 6.510~cm of the
progenitor, from a phase of advanced pre-SN mass loss shortly before explosion.
Spectropolarimetry of SN2013fs shows little continuum polarization, but
noticeable line polarization during the plateau phase. SN2013fr morphed from a
SNIIn at early times to a SNII-L. After the first epoch its narrow lines
probably arose from host-galaxy emission, but the bright, narrow H
emission at early times may be intrinsic. As for SN2013fs, this would point to
a short-lived phase of strong CSM interaction if proven to be intrinsic,
suggesting a continuum between SNeIIn and II-L. It is a low-velocity SNII-L,
like SN2009kr but more luminous. SN2013fr also developed an IR excess at later
times, due to warm CSM dust that require a more sustained phase of strong
pre-SN mass loss.Comment: MNRAS accepted. 28 pages, 23 figures, 8 table
The physicochemical investigation of hydrothermally reduced textile waste and application within carbon-based electrodes.
From Europe PMC via Jisc Publications RouterHistory: ppub 2019-04-01, epub 2019-04-10Publication status: PublishedTextile waste is on the rise due to the expanding global population and the fast fashion market. Large volumes of textile waste are increasing the need for new methods for recycling mixed fabric materials. This paper employs a hydrothermal conversion route for a polyester/cotton mix in phosphoric acid to generate carbon materials (hydrochars) for electrochemical applications. A combination of characterization techniques revealed the reaction products were largely comprised of two major components. The first is a granular material with a surface C : O ratio of 2 : 1 interspersed with phosphorous and titanium proved using energy dispersive X-ray spectroscopy, and the other is a crystalline material with a surface C : O ratio of 3 : 2 containing no phosphorous or titanium. The latter material was found via X-ray diffraction and differential scanning calorimetry to be terephthalic acid. Electrochemical experiments conducted using the hydrochar as a carbon paste electrode demonstrates an increase in current response compared to carbon reference materials. The improved current responses, intrinsically related to the surface area of the material, could be beneficial for electrochemical sensor applications, meaning that this route holds promise for the development of a cheap recycled carbon material, using straightforward methods and simple laboratory reagents
Encoders for block-circulant LDPC codes
Methods and apparatus to encode message input symbols in accordance with an accumulate-repeat-accumulate code with repetition three or four are disclosed. Block circulant matrices are used. A first method and apparatus make use of the block-circulant structure of the parity check matrix. A second method and apparatus use block-circulant generator matrices
ARA type protograph codes
An apparatus and method for encoding low-density parity check codes. Together with a repeater, an interleaver and an accumulator, the apparatus comprises a precoder, thus forming accumulate-repeat-accumulate (ARA codes). Protographs representing various types of ARA codes, including AR3A, AR4A and ARJA codes, are described. High performance is obtained when compared to the performance of current repeat-accumulate (RA) or irregular-repeat-accumulate (IRA) codes
Methadone-induced mortality in the treatment of chronic pain: Role of QT prolongation
Methadone is increasingly prescribed for chronic pain, yet the associated mortality appears to be
rising disproportionately relative to other opioid analgesics. We review the available evidence on
methadone-associated mortality, and explore potential pharmacokinetic and pharmacodynamic
explanations for its greater apparent lethality. While methadone shares properties of central
nervous system and respiratory depression with other opioids, methadone is unique as a potent
blocker of the delayed rectifier potassium ion channel (IKr). This results in QT-prolongation
and torsade de pointes (TdP) in susceptible individuals. In some individuals with low serum
protein binding of methadone, the extent of blockade is roughly comparable to that of sotalol,
a potent QT-prolonging drug. Predicting an individual’s propensity for methadone-induced
TdP is difficult at present given the inherent limitations of the QT interval as a risk-stratifier
combined with the multifactorial nature of the arrhythmia. Consensus recommendations have
recently been published to mitigate the risk of TdP until further studies better define the
arrhythmia risk factors for methadone. Studies are needed to provide insights into the clinical
covariates most likely to result in methadone-associated arrhythmia and to assess the feasibility
of current risk mitigation strategies
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