4,379 research outputs found
Volcanic smog and cardiometabolic health: Hawaiian hypertension?
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149349/1/jch13500.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149349/2/jch13500_am.pd
Hierarchical formation of bulgeless galaxies II: Redistribution of angular momentum via galactic fountains
Within a fully cosmological hydrodynamical simulation, we form a galaxy which
rotates at 140 km/s, and is characterised by two loose spiral arms and a bar,
indicative of a Hubble Type SBc/d galaxy. We show that our simulated galaxy has
no classical bulge, with a pure disc profile at z=1, well after the major
merging activity has ended. A long-lived bar subsequently forms, resulting in
the formation of a secularly-formed "pseudo" bulge, with the final
bulge-to-total light ratio B/T=0.21. We show that the majority of gas which
loses angular momentum and falls to the central region of the galaxy during the
merging epoch is blown back into the hot halo, with much of it returning later
to form stars in the disc. We propose that this mechanism of redistribution of
angular momentum via a galactic fountain, when coupled with the results from
our previous study which showed why gas outflows are biased to have low angular
momentum, can solve the angular momentum/bulgeless disc problem of the cold
dark matter paradigm.Comment: 9 Pages, 10 Figures, accepted MNRAS version. Comments welcom
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Midwifery students' experiences in a health visiting placement: An interview study
In the UK, there is a clear remit for midwives and health visitors to work collaboratively to care for pregnant women and new mothers. This study evaluated a clinical placement for midwifery students with health visitor mentors. The evaluation explored the experience of mentors and students during the placement, the effect on their understanding of the different roles and the potential effect on collaborative working in the future. Results indicated that students developed their knowledge of the health visitor role and learned transferable skills to take back to midwifery. They saw little collaborative practice, but identified ways to incorporate interprofessional working into their practice once qualified. Mentors were positive about sharing health visiting practice and the potential impact on relationships in the future
Momentum Spectra in the Current Region of the Breit Frame in Deep Inelastic Scattering at HERA
The production of charged particles has been measured in deep inelastic
scattering (DIS) with the ZEUS detector. The evolution of the moments of the
scaled momenta distributions in and has been investigated in the
current fragmentation region of the Breit frame. The results in the current
region are compared to data and QCD analytical calculations. The
results are consistent with the universality of single-particle spectra in DIS
and annihilation at high The results at low disagree with
analytical calculations based on the modified leading log approximation (MLLA)
and local parton hadron duality (LPHD).Comment: 3 pages. 1 postscript figure + 1 postscript preprint logo + 1 LaTeX
file + 1 style fil
Trigger point manual therapy for the treatment of chronic non-cancer pain in adults
This is the protocol for a review and there is no abstract. The objectives are as follows:
To determine the effectiveness of trigger point manual therapy for treating chronic non-cancer pain in adults
Identifying and Tracking Proteins Through the Marine Water Column: Insights Into the Inputs and Preservation Mechanisms of Protein in Sediments
Proteins generated during primary production represent an important fraction of marine organic nitrogen and carbon, and have the potential to provide organism-specific information in the environment. The Bering Sea is a highly productive system dominated by seasonal blooms and was used as a model system for algal proteins to be tracked through the water column and incorporated into detrital sedimentary material. Samples of suspended and sinking particles were collected at multiple depths along with surface sediments on the continental shelf and deeper basin of the Bering Sea. Modified standard proteomic preparations were used in conjunction with high pressure liquid chromatography-tandem mass spectrometry to identify the suite of proteins present and monitor changes in their distribution. In surface waters 207 proteins were identified, decreasing through the water column to 52 proteins identified in post-bloom shelf surface sediments and 24 proteins in deeper (3490 m) basin sediments. The vast majority of identified proteins in all samples were diatom in origin, reflecting their dominant contribution of biomass during the spring bloom. Identified proteins were predominantly from metabolic, binding/structural, and transport-related protein groups. Significant linear correlations were observed between the number of proteins identified and the concentration of total hydrolysable amino acids normalized to carbon and nitrogen. Organelle-bound, transmembrane, photosynthetic, and other proteins involved in light harvesting were preferentially retained during recycling. These findings suggest that organelle and membrane protection represent important mechanisms that enhance the preservation of protein during transport and incorporation into sediments
Thin disc, Thick Disc and Halo in a Simulated Galaxy
Within a cosmological hydrodynamical simulation, we form a disc galaxy with
sub- components which can be assigned to a thin stellar disc, thick disk, and a
low mass stellar halo via a chemical decomposition. The thin and thick disc
populations so selected are distinct in their ages, kinematics, and
metallicities. Thin disc stars are young (<6.6 Gyr), possess low velocity
dispersion ({\sigma}U,V,W = 41, 31, 25 km/s), high [Fe/H], and low [O/Fe]. The
thick disc stars are old (6.6<age<9.8 Gyrs), lag the thin disc by \sim21 km/s,
possess higher velocity dispersion ({\sigma}U,V,W = 49, 44, 35 km/s),
relatively low [Fe/H] and high [O/Fe]. The halo component comprises less than
4% of stars in the "solar annulus" of the simulation, has low metallicity, a
velocity ellipsoid defined by ({\sigma}U,V,W = 62, 46, 45 km/s) and is formed
primarily in-situ during an early merger epoch. Gas-rich mergers during this
epoch play a major role in fuelling the formation of the old disc stars (the
thick disc). This is consistent with studies which show that cold accretion is
the main source of a disc galaxy's baryons. Our simulation initially forms a
relatively short (scalelength \sim1.7 kpc at z=1) and kinematically hot disc,
primarily from gas accreted during the galaxy's merger epoch. Far from being a
competing formation scenario, migration is crucial for reconciling the short,
hot, discs which form at high redshift in {\Lambda}CDM, with the properties of
the thick disc at z=0. The thick disc, as defined by its abundances maintains
its relatively short scale-length at z = 0 (2.31 kpc) compared with the total
disc scale-length of 2.73 kpc. The inside-out nature of disc growth is
imprinted the evolution of abundances such that the metal poor {\alpha}-young
population has a larger scale-length (4.07 kpc) than the more chemically
evolved metal rich {\alpha}-young population (2.74 kpc).Comment: Submitted to MNRAS. This version after helpful referee comments.
Comments welcome to [email protected]
Evaluation of Electrophoretic Protein Extraction and Database-Driven Protein Identification from Marine Sediments
Intact proteins comprise a major component of organic carbon and nitrogen produced globally and are likely an important fraction of organic matter in sediments and soils. Extracting the protein component from sediments and soils for mass spectral characterization and identification represents a substantial challenge given the range of products and functionalities present in the complex matrix. Multiple forms of gel electrophoresis were evaluated as a means of enhancing recovery of sedimentary protein before proteomic characterization and compared with a direct enzymatic digestion of proteins in sediments. Resulting tryptic peptides were analyzed using shotgun proteomics and tandem mass spectra were evaluated with SEQUEST. Multiple databases were then evaluated to examine the ability to confidently identify proteins from environmental samples. Following evaluation of electrophoretic extraction of proteins from sediments, the recovery of an experimentally added standard protein (BSA) from older (\u3e1 ky) sediments was optimized. Protein extraction from sediments via direct electrophoresis of a slurry mixture and the specified extraction buffer resulted in the greatest number of confident protein identifications and highest sequence coverage of the BSA standard. Searching tandem mass spectral data against larger databases with a higher diversity of proteomes did not yield a greater number of, or more confidence in, protein identifications. Regardless of the protein database used, identified peptides correlated to proteins with the same function across taxa. This suggests that while determining taxonomic-level information remains a challenge in samples with unknown mixed species, it is possible to confidently assign the function of the identified protein
Protein Recycling in Bering Sea Algal Incubations
Protein present in phytoplankton represents a large fraction of the organic nitrogen and carbon transported from its synthesis in surface waters to marine sediments. Yet relatively little is known about the longevity of identifiable protein in situ, or the potential modifications to proteins that occur during bloom termination, protein recycling and degradation. To address this knowledge gap, diatom-dominated phytoplankton was collected during the Bering Sea spring blooms of 2009 and 2010, and incubated under darkness in separate shipboard degradation experiments spanning 11 and 53 d, respectively. In each experiment, the protein distribution was monited over time using shotgun proteomics, along with total hydrolyzable amino acids (THAAs), total protein, particulate organic carbon (POC) and nitrogen (PN), and bacterial cell abundance. Identifiable proteins, total protein and THAAs were rapidly lost during the first 5 d of enclosure in darkness in both incubations. Thereafter the loss rate was slower, and it declined further after 22 d. The initial loss of identifiable biosynthetic, glycolysis, metabolism and translation proteins after 12 h may represent shutdown of cellular activity among algal cells. Additional peptides with glycan modifications were identified in early incubation time points, suggesting that such protein modifications could be used as a marker for internal recycling processes and possibly cell death. Protein recycling was not uniform, with a subset of algal proteins including fucoxanthin chlorophyll binding proteins and RuBisCO identified after 53 d of degradation. Non-metric multidimensional scaling was used to compare the incubations with previous environmental results. The results confirmed recent observations that some fraction of algal proteins can survive water column recycling and undergo transport to marine sediments, thus contributing organic nitrogen to the benthos
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