4,872 research outputs found
"Tremendous Financial Burden": Crowdfunding for Organ Transplantation Costs in Canada
Online crowdfunding platforms such as GoFundMe are used to raise funds for health-related expenses associated with medical conditions such as organ transplantation. By investigating crowdfunding in Canadian organ transplantation, this study aimed to increase understanding of the motivations and outcomes of organ transplantation crowdfunding. Canadian liver and kidney transplantation campaigns posted to GoFundMe between May 30 & 31 2018 were identified and after exclusion, 258 kidney and 171 liver campaigns were included in study. These campaigns were coded for: worthiness of the campaign recipient, requested financial and non-monetary contributions, how monetary donations would be spent, and comments on the Canadian health system, among others. Results suggest Canadian organ donors, transplant candidates, recipients, and their families and caregivers experience significant financial difficulties not addressed by the public health system. Living and medication costs, transportation and relocation expenses, and income loss were the expenses most commonly highlighted by campaigners. Liver campaigns raised nearly half their goal while kidney campaigns received 11.5% of their requested amount. Findings highlight disease burden and the use of crowdfunding as a response to the extraordinary costs associated with organ transplantation. Although crowdfunding reduces some financial burden, it does not do so equitably and raises ethical concerns
Viral RNA at two stages of reovirus infection is required for the induction of necroptosis
Necroptosis, a regulated form of necrotic cell death, requires the activation of the RIP3 kinase. Here, we identify that infection of host cells with reovirus can result in necroptosis. We find that necroptosis requires sensing of the genomic RNA within incoming virus particles via cytoplasmic RNA sensors to produce type I interferon (IFN). While these events that occur prior to the de novo synthesis of viral RNA are required for the induction of necroptosis, they are not sufficient. The induction of necroptosis also requires late stages of reovirus infection. Specifically, efficient synthesis of double-stranded RNA (dsRNA) within infected cells is required for necroptosis. These data indicate that viral RNA interfaces with host components at two different stages of infection to induce necroptosis. This work provides new molecular details about events in the viral replication cycle that contribute to the induction of necroptosis following infection with an RNA virus. IMPORTANCE An appreciation of how cell death pathways are regulated following viral infection may reveal strategies to limit tissue destruction and prevent the onset of disease. Cell death following virus infection can occur by apoptosis or a regulated form of necrosis known as necroptosis. Apoptotic cells are typically disposed of without activating the immune system. In contrast, necroptotic cells alert the immune system, resulting in inflammation and tissue damage. While apoptosis following virus infection has been extensively investigated, how necroptosis is unleashed following virus infection is understood for only a small group of viruses. Here, using mammalian reovirus, we highlight the molecular mechanism by which infection with a dsRNA virus results in necroptosis
Simultaneous Observations of Comet C/2002 T7 (LINEAR) with the Berkeley-Illinois-Maryland Association and Owens Valley Radio Observatory Interferometers: HCN and CH_3OH
We present observations of HCN J = 1-0 and CH_3OH J(K_a, K_c) = 3(1, 3)-4(0, 4) A+ emission from comet C/2002 T7 (LINEAR) obtained simultaneously with the Owens Valley Radio Observatory (OVRO) and Berkeley-Illinois-Maryland Association (BIMA) millimeter interferometers. We combined the data from both arrays to increase the (u, v) sampling and signal to noise of the detected line emission. We also report the detection of CH_3OH J(K_a, K_c) = 8(0, 8)-7(1, 7) A^+ with OVRO data alone. Using a molecular excitation code that includes the effects of collisions with water and electrons, as well as pumping by the Solar infrared photons (for HCN alone), we find a production rate of HCN of 2.9 × 10^(26) s^(–1) and for CH_3OH of 2.2 × 10^(27) s^(–1). Compared to the adopted water production rate of 3 × 10^(29) s^(–1), this corresponds to an HCN/H_2O ratio of 0.1% and a CH_3OH/H_2O ratio of 0.7%. We critically assess the uncertainty of these values due to the noise (~10%), the uncertainties in the adopted comet model (~50%), and the uncertainties in the adopted collisional excitation rates (up to a factor of 2). Pumping by Solar infrared photons is found to be a minor effect for HCN, because our 15" synthesized beam is dominated by the region in the coma where collisions dominate. Since the uncertainties in the derived production rates are at least as large as one-third of the differences found between comets, we conclude that reliable collision rates and an accurate comet model are essential. Because the collisionally dominated region critically depends on the water production rate, using the same approximate method for different comets may introduce biases in the derived production rates. Multiline observations that directly constrain the molecular excitation provide much more reliable production rates
A Search for Hydroxylamine (NH2OH) toward Select Astronomical Sources
Observations of 14 rotational transitions of hydroxylamine (NH2OH) using the
NRAO 12 m Telescope on Kitt Peak are reported towards IRC+10216, Orion KL,
Orion S, Sgr B2(N), Sgr B2(OH), W3IRS5, and W51M. Although recent models
suggest the presence of NH2OH in high abundance, these observations resulted in
non-detection. Upper limits are calculated to be as much as six orders of
magnitude lower than predicted by models. Possible explanations for the lower
than expected abundance are explored.Comment: 18 pages, 3 figures, 3 table
Academic Priority: Graduate/Doctoral Research
Overview Doctoral Education at UNO: Past, Present, and Future
Observational Results of a Multi-Telescope Campaign in Search of Interstellar Urea [(NH)CO]
In this paper, we present the results of an observational search for gas
phase urea [(NH)CO] observed towards the Sgr B2(N-LMH) region. We show
data covering urea transitions from 100 GHz to 250 GHz from five
different observational facilities: BIMA, CARMA, the NRAO 12 m telescope, the
IRAM 30 m telescope, and SEST. The results show that the features ascribed to
urea can be reproduced across the entire observed bandwidth and all facilities
by best fit column density, temperature, and source size parameters which vary
by less than a factor of 2 between observations merely by adjusting for
telescope-specific parameters. Interferometric observations show that the
emission arising from these transitions is cospatial and compact, consistent
with the derived source sizes and emission from a single species. Despite this
evidence, the spectral complexity, both of (NH)CO and of Sgr B2(N),
makes the definitive identification of this molecule challenging. We present
observational spectra, laboratory data, and models, and discuss our results in
the context of a possible molecular detection of urea.Comment: 38 pages, 9 Figures, accepted in the Astrophysical Journa
First Acetic Acid Survey with CARMA in Hot Molecular Cores
Acetic acid (CHCOOH) has been detected mainly in hot molecular cores
where the distribution between oxygen (O) and nitrogen (N) containing molecular
species is co-spatial within the telescope beam. Previous work has presumed
that similar cores with co-spatial O and N species may be an indicator for
detecting acetic acid. However, does this presumption hold as higher spatial
resolution observations become available of large O and N-containing molecules?
As the number of detected acetic acid sources is still low, more observations
are needed to support this postulate. In this paper, we report the first acetic
acid survey conducted with the Combined Array for Research in Millimeter-wave
Astronomy (CARMA) at 3 mm wavelengths towards G19.61-0.23, G29.96-0.02 and IRAS
16293-2422. We have successfully detected CHCOOH via two transitions toward
G19.61-0.23 and tentatively confirmed the detection toward IRAS 16293-2422 A.
The determined column density of CHCOOH is 2.0(1.0)
cm and the abundance ratio of CHCOOH to methyl formate (HCOOCH)
is 2.2(0.1) toward G19.61-0.23. Toward IRAS 16293 A, the
determined column density of CHCOOH is 1.6
cm and the abundance ratio of CHCOOH to methyl formate (HCOOCH)
is 1.0 both of which are consistent with abundance
ratios determined toward other hot cores. Finally, we model all known line
emission in our passband to determine physical conditions in the regions and
introduce a new metric to better reveal weak spectral features that are blended
with stronger lines or that may be near the 1-2 detection limit.Comment: 28 pages, 8 figures, accepted for publication in the ApJ; Revised
citation in session 2, references remove
A Bima Array Survey of Molecules in Comets Linear (C/2002 T7) and Neat (C/2001 Q4)
We present an interferometric search for large molecules, including methanol,
methyl cyanide, ethyl cyanide, ethanol, and methyl formate in comets LINEAR
(C/2002 T7) and NEAT (C/2001 Q4) with the Berkeley-Illinois-Maryland
Association (BIMA) array. In addition, we also searched for transitions of the
simpler molecules CS, SiO, HNC, HN13C and 13CO . We detected transitions of
methanol and CS around Comet LINEAR and one transition of methanol around Comet
NEAT within a synthesized beam of ~20''. We calculated the total column density
and production rate of each molecular species using the variable temperature
and outflow velocity (VTOV) model described by Friedel et al.(2005).Considering
the molecular production rate ratios with respect to water, Comet T7 LINEAR is
more similar to Comet Hale-Bopp while Comet Q4 NEAT is more similar to Comet
Hyakutake. It is unclear, however, due to such a small sample size, whether
there is a clear distinction between a Hale-Bopp and Hyakutake class of comet
or whether comets have a continuous range of molecular production rate ratios.Comment: Accepted for Publication in the Astrophysical Journa
The Distribution, Excitation and Formation of Cometary Molecules: Methanol, Methyl Cyanide and Ethylene Glycol
We present an interferometric and single dish study of small organic species
toward Comets C/1995 O1 (Hale-Bopp) and C/2002 T7 (LINEAR) using the BIMA
interferometer at 3 mm and the ARO 12m telescope at 2 mm. For Comet Hale-Bopp,
both the single-dish and interferometer observations of CH3OH indicate an
excitation temperature of 105+/-5 K and an average production rate ratio
Q(CH3OH)/Q(H2O)~1.3% at ~1 AU. Additionally, the aperture synthesis
observations of CH3OH suggest a distribution well described by a spherical
outflow and no evidence of significant extended emission. Single-dish
observations of CH3CN in Comet Hale-Bopp indicate an excitation temperature of
200+/-10 K and a production rate ratio of Q(CH3CN)/Q(H2O)~0.017% at ~1 AU. The
non-detection of a previously claimed transition of cometary (CH2OH)2 toward
Comet Hale-Bopp with the 12m telescope indicates a compact distribution of
emission, D<9'' (<8500 km). For the single-dish observations of Comet T7
LINEAR, we find an excitation temperature of CH3OH of 35+/-5 K and a CH3OH
production rate ratio of Q(CH3OH)/Q(H2O)~1.5% at ~0.3 AU. Our data support
current chemical models that CH3OH, CH3CN and (CH2OH)2 are parent nuclear
species distributed into the coma via direct sublimation off cometary ices from
the nucleus with no evidence of significant production in the outer coma.Comment: accepted for publication in Ap
- …