To reduce widespread shortages, attempts are made to use more marginal livers for transplantation. Many of these grafts are discarded for fear of inferior survival rates or biliary complications. ...Recent advances in organ preservation have shown that ex vivo subnormothermic machine perfusion has the potential to improve preservation and recover marginal livers pretransplantation. To determine the feasibility in human livers, we assessed the effect of 3 h of oxygenated subnormothermic machine perfusion (21°C) on seven livers discarded for transplantation. Biochemical and microscopic assessment revealed minimal injury sustained during perfusion. Improved oxygen uptake (1.30 1.11–1.94 to 6.74 4.15–8.16 mL O2/min kg liver), lactate levels (4.04 3.70–5.99 to 2.29 1.20–3.43 mmol/L) and adenosine triphosphate content (45.0 70.6–87.5 pmol/mg preperfusion to 167.5 151.5–237.2 pmol/mg after perfusion) were observed. Liver function, reflected by urea, albumin and bile production, was seen during perfusion. Bile production increased and the composition of bile (bile salts/phospholipid ratio, pH and bicarbonate concentration) became more favorable. In conclusion, ex vivo subnormothermic machine perfusion effectively maintains liver function with minimal injury and sustains or improves various hepatobiliary parameters postischemia.
This study of human livers shows that subnormothermic machine perfusion can preserve hepatobiliary function and may be feasible for liver graft recovery pretransplantation.
The emergence of pandemic H1N1/2009 influenza demonstrated that pandemic viruses could be generated in swine. Subsequent reintroduction of H1N1/2009 to swine has occurred in multiple countries. ...Through systematic surveillance of influenza viruses in swine from a Hong Kong abattoir, we characterize a reassortant progeny of H1N1/2009 with swine viruses. Swine experimentally infected with this reassortant developed mild illness and transmitted infection to contact animals. Continued reassortment of H1N1/2009 with swine influenza viruses could produce variants with transmissibility and altered virulence for humans. Global systematic surveillance of influenza viruses in swine is warranted.
UK Biobank is a population-based cohort of half a million participants aged 40-69 years recruited between 2006 and 2010. In 2014, UK Biobank started the world's largest multi-modal imaging study, ...with the aim of re-inviting 100,000 participants to undergo brain, cardiac and abdominal magnetic resonance imaging, dual-energy X-ray absorptiometry and carotid ultrasound. The combination of large-scale multi-modal imaging with extensive phenotypic and genetic data offers an unprecedented resource for scientists to conduct health-related research. This article provides an in-depth overview of the imaging enhancement, including the data collected, how it is managed and processed, and future directions.
The modification of star formation (SF) in galaxy interactions is a complex process, with SF observed to be both enhanced in major mergers and suppressed in minor pair interactions. Such changes ...likely to arise on short time-scales and be directly related to the galaxy–galaxy interaction time. Here we investigate the link between dynamical phase and direct measures of SF on different time-scales for pair galaxies, targeting numerous star- formation rate (SFR) indicators and comparing to pair separation, individual galaxy mass and pair mass ratio. We split our sample into the higher (primary) and lower (secondary) mass galaxies in each pair and find that SF is indeed enhanced in all primary galaxies but suppressed in secondaries of minor mergers. We find that changes in SF of primaries are consistent in both major and minor mergers, suggesting that SF in the more massive galaxy is agnostic to pair mass ratio. We also find that SF is enhanced/suppressed more strongly for short-duration SFR indicators (e.g. Hα), highlighting recent changes to SF in these galaxies, which are likely to be induced by the interaction. We propose a scenario where the lower mass galaxy has its SF suppressed by gas heating or stripping, while the higher mass galaxy has its SF enhanced, potentially by tidal gas turbulence and shocks. This is consistent with the seemingly contradictory observations for both SF suppression and enhancement in close pairs.
The Schizophrenia Psychiatric Genome-Wide Association Study Consortium (PGC) highlighted 81 single-nucleotide polymorphisms (SNPs) with moderate evidence for association to schizophrenia. After ...follow-up in independent samples, seven loci attained genome-wide significance (GWS), but multi-locus tests suggested some SNPs that did not do so represented true associations. We tested 78 of the 81 SNPs in 2640 individuals with a clinical diagnosis of schizophrenia attending a clozapine clinic (CLOZUK), 2504 cases with a research diagnosis of bipolar disorder, and 2878 controls. In CLOZUK, we obtained significant replication to the PGC-associated allele for no fewer than 37 (47%) of the SNPs, including many prior GWS major histocompatibility complex (MHC) SNPs as well as 3/6 non-MHC SNPs for which we had data that were reported as GWS by the PGC. After combining the new schizophrenia data with those of the PGC, variants at three loci (ITIH3/4, CACNA1C and SDCCAG8) that had not previously been GWS in schizophrenia attained that level of support. In bipolar disorder, we also obtained significant evidence for association for 21% of the alleles that had been associated with schizophrenia in the PGC. Our study independently confirms association to three loci previously reported to be GWS in schizophrenia, and identifies the first GWS evidence in schizophrenia for a further three loci. Given the number of independent replications and the power of our sample, we estimate 98% (confidence interval (CI) 78-100%) of the original set of 78 SNPs represent true associations. We also provide strong evidence for overlap in genetic risk between schizophrenia and bipolar disorder.
Abstract
We present the calibration between the dust continuum luminosity and interstellar gas content obtained from the Valparaíso ALMA Line Emission Survey (VALES) sample of 67 main-sequence ...star-forming galaxies at 0.02 < z < 0.35. We use CO(1–0) observations from the Atacama Large Millimetre/submillimetre Array to trace the molecular gas mass, M
H
2, and estimate the rest-frame monochromatic luminosity at 850 μm,
$L_{\nu _{850}}$
, by extrapolating the dust continuum from magphys modelling of the far-ultraviolet to submillimetre spectral energy distribution sampled by the Galaxy And Mass Assembly survey. Adopting αCO = 6.5 (K km s−1 pc2)−1, the average ratio of
$L_{\nu _{850}}$
/M
H
2 = (6.4 ± 1.4)× 1019 erg s−1 Hz−1 M
$_{{\odot }}^{-1}$
, in excellent agreement with literature values. We obtain a linear fit of
$\log _{10} \left({M}_{\mathrm{H}_{2}}/{\mathrm{M}_{{\odot }}}\right) = (0.92\pm 0.02) \log _{10} (L_{\nu _{850}}/{\mathrm{erg}\,\mathrm{s}^{-1}\,\mathrm{Hz}^{-1}})-(17.31\pm 0.59)$
. We provide relations between
$L_{\nu _{850}}$
, M
H
2 and M
ISM when combining the VALES and literature samples, and adopting a Galactic αCO value.
Anatomy of STEM teaching in North American universities Stains, M; Harshman, J; Barker, M K ...
Science (American Association for the Advancement of Science),
2018-Mar-30, 2018-03-30, 20180330, Letnik:
359, Številka:
6383
Journal Article
Recenzirano
Odprti dostop
Lecture is prominent, but practices vary
A large body of evidence demonstrates that strategies that promote student interactions and cognitively engage students with content (
1
) lead to gains in ...learning and attitudinal outcomes for students in science, technology, engineering, and mathematics (STEM) courses (
1
,
2
). Many educational and governmental bodies have called for and supported adoption of these student-centered strategies throughout the undergraduate STEM curriculum. But to the extent that we have pictures of the STEM undergraduate instructional landscape, it has mostly been provided through self-report surveys of faculty members, within a particular STEM discipline e.g., (
3
–
6
). Such surveys are prone to reliability threats and can underestimate the complexity of classroom environments, and few are implemented nationally to provide valid and reliable data (
7
). Reflecting the limited state of these data, a report from the U.S. National Academies of Sciences, Engineering, and Medicine called for improved data collection to understand the use of evidence-based instructional practices (
8
). We report here a major step toward a characterization of STEM teaching practices in North American universities based on classroom observations from over 2000 classes taught by more than 500 STEM faculty members across 25 institutions.
Hematoma expansion (HE) is a surrogate marker in intracerebral hemorrhage (ICH) trials. However, the amount of HE necessary to produce poor outcomes in an individual is unclear; there is no agreement ...on a clinically meaningful definition of HE. We compared commonly used definitions of HE in their ability to predict poor outcome as defined by various cutpoints on the modified Rankin Scale (mRS).
In this cohort study, we analyzed 531 patients with ICH from the Virtual International Stroke Trials Archive. Primary outcome was mRS at 90 days, dichotomized into 0-3 vs 4-6. Secondary outcomes included other mRS cutpoints and mRS "shift analysis." Sensitivity, specificity, and predictive values for commonly used HE definitions were calculated.
Between 13% and 32% of patients met the commonly used HE definitions. All definitions independently predicted poor outcome; positive predictive values increased with higher growth cutoffs but at the expense of lower sensitivities. All HE definitions showed higher specificity than sensitivity. Absolute growth cutoffs were more predictive than relative cutoffs when mRS 5-6 or 6 was defined as "poor outcome."
HE robustly predicts poor outcome regardless of the growth definition or the outcome definition. The highest positive predictive values are obtained when using an absolute growth definition to predict more severe outcomes. Given that only a minority of patients may have clinically relevant HE, hemostatic ICH trials may need to enroll a large number of patients, or select for a population that is more likely to have HE.
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