2,550 research outputs found
Should we mine the deep seafloor?
As land-based mineral resources become increasingly difficult and expensive to acquire, the potential for mining resources from the deep seafloor has become widely discussed and debated. Exploration leases are being granted, and technologies are under development. However, the quantity and quality of the resources are uncertain, and many worry about risks to vulnerable deep-sea ecosystems. Deep-sea mining has become part of the discussion of the United Nations Sustainable Development Goals. In this article we provide a summary of benefits, costs, and uncertainties that surround this potentially attractive but contentious topic
Single seed sorting technology and its interaction with processing for food, malt, feed and industrial markets
Non-Peer Reviewe
Re-examination of the possible tidal stream in front of the LMC
It has recently been suggested that the stars in a vertical extension of the
red clump feature seen in LMC color-magnitude diagrams could belong to a tidal
stream of material located in front of that galaxy. If this claim is correct,
this foreground concentration of stars could contribute significantly to the
rate of gravitational microlensing events observed in the LMC microlensing
experiments. Here we present radial velocity measurements of stars in this
so-called ``vertical red clump'' (VRC) population. The observed stellar sample,
it transpires, has typical LMC kinematics. It is shown that it is improbable
that an intervening tidal stream should have the same distribution of radial
velocities as the LMC, which is consistent with an earlier study that showed
that the VRC feature is more likely a young stellar population in the main body
of that galaxy. However, the kinematic data do not discriminate against the
possibility that the VRC is an LMC halo population.Comment: 10 pages, 3 figures, 1 table. Accepted for publication in ApJ
MOA-2011-BLG-293Lb: First Microlensing Planet possibly in the Habitable Zone
We used Keck adaptive optics observations to identify the first planet
discovered by microlensing to lie in or near the habitable zone, i.e., at
projected separation AU from its host, being the highest microlensing mass definitely identified.
The planet has a mass , and could in principle
have habitable moons. This is also the first planet to be identified as being
in the Galactic bulge with good confidence: kpc. The
planet/host masses and distance were previously not known, but only estimated
using Bayesian priors based on a Galactic model (Yee et al. 2012). These
estimates had suggested that the planet might be a super-Jupiter orbiting an M
dwarf, a very rare class of planets. We obtained high-resolution images
using Keck adaptive optics to detect the lens and so test this hypothesis. We
clearly detect light from a G dwarf at the position of the event, and exclude
all interpretations other than that this is the lens with high confidence
(95%), using a new astrometric technique. The calibrated magnitude of the
planet host star is . We infer the following probabilities
for the three possible orbital configurations of the gas giant planet: 53% to
be in the habitable zone, 35% to be near the habitable zone, and 12% to be
beyond the snow line, depending on the atmospherical conditions and the
uncertainties on the semimajor axis.Comment: Accepted by ApJ, 21 pages, 4 figure
Impact of Level of Effort on the Effects of Compliance with the 3-Hour Rule
Objective
To determine if patientsâ level of effort (LOE) in therapy sessions during traumatic brain injury (TBI) rehabilitation modifies the effect of compliance with the 3-Hour Rule of the Centers for Medicare & Medicaid Services.
Design
Propensity score methodology applied to the TBI-Practice-Based Evidence (TBI-PBE) database, consisting of multi-site, prospective, longitudinal observational data.
Setting
Acute inpatient rehabilitation facilities (IRF).
Participants
Patients (n=1820) who received their first IRF admission for TBI in the US and were enrolled for 3 and 9 month follow-up.
Main Outcome Measures
Participation Assessment with Recombined Tools-Objective-17, FIMTM Motor and Cognitive scores, Satisfaction with Life Scale, and Patient Health Questionnaire-9.
Results
When the full cohort was examined, no strong main effect of compliance with the 3-Hour Rule was identified and LOE did not modify the effect of compliance with the 3-Hour Rule. In contrast, LOE had a strong positive main effect on all outcomes, except depression. When the sample was stratified by level of disability, LOE modified the effect of compliance, particularly on the outcomes of participants with less severe disability. For these patients, providing 3 hours of therapy for 50%+ of therapy days in the context of low effort resulted in poorer performance on select outcome measures at discharge and up to 9 months post discharge compared to patients with <50% of 3-hr therapy days.
Conclusions
LOE is an active ingredient in inpatient TBI rehabilitation, while compliance with the 3-Hour Rule was not found to have a substantive impact on the outcomes. The results support matching time in therapy during acute TBI rehabilitation to patientsâ LOE in order to optimize long-term benefits on outcomes
FMR studies of exchange-coupled multiferroic polycrystalline Pt/BiFeO/NiFe/Pt heterostructures
An experimental study of the in-plane azimuthal behaviour and frequency
dependence of the ferromagnetic resonance field and the resonance linewidth as
a function of BiFeO thickness is carried out in a polycrystalline
exchange-biased BiFeO/NiFe system. The magnetization decrease
of the Pt/BiFeO/NiFe/Pt heterostructures with BiFeO
thickness deduced from static measurements has been confirmed by dynamic
investigations. Ferromagnetic resonance measurements have shown lower
gyromagnetic ratio in a perpendicular geometry compared with that of a parallel
geometry. The monotonous decrease of gyromagnetic ratio in a perpendicular
geometry as a function of the BiFeO film thickness seems to be related to
the spin-orbit interactions due to the neighbouring Pt film at its interface
with NiFe film. The in-plane azimuthal shape of the total
linewidth of the uniform mode shows isotropic behaviour that increases with
BiFeO thickness. The study of the frequency dependence of the resonance
linewidth in a broad band of 3 to 35 GHz has allowed the determination of
intrinsic and extrinsic contributions to the relaxation as function of
BiFeO thickness in perpendicular geometries. In our system the magnetic
relaxation is dominated by the spin-pumping mechanism due to the presence of
Pt. The insertion of BiFeO between Pt and NiFe attenuates the
spin-pumping damping at one interface.Comment: paper accepted for publication in the Journal of Physics D: Applied
Physic
Signals for a Transition from Surface to Bulk Emission in Thermal Multifragmentation
Excitation-energy-gated two-fragment correlation functions have been studied
between 2 to 9A MeV of excitation energy for equilibrium-like sources formed in
and p + Au reactions at beam momenta of 8,9.2 and 10.2 GeV/c.
Comparison of the data to an N-body Coulomb-trajectory code shows a decrease of
one order of magnitude in the fragment emission time in the excitation energy
interval 2-5A MeV, followed by a nearly constant breakup time at higher
excitation energy. The observed decrease in emission time is shown to be
strongly correlated with the increase of the fragment emission probability, and
the onset of thermally-induced radial expansion. This result is interpreted as
evidence consistent with a transition from surface-dominated to bulk emission
expected for spinodal decomposition.Comment: 11 pages including 3 postscript figures (1 color
Thermally-induced expansion in the 8 GeV/c + Au reaction
Fragment kinetic energy spectra for reactions induced by 8.0 GeV/c
beams incident on a Au target have been analyzed in
order to deduce the possible existence and influence of thermal expansion. The
average fragment kinetic energies are observed to increase systematically with
fragment charge but are nearly independent of excitation energy. Comparison of
the data with statistical multifragmentation models indicates the onset of
extra collective thermal expansion near an excitation energy of E*/A
5 MeV. However, this effect is weak relative to the radial
expansion observed in heavy-ion-induced reactions, consistent with the
interpretation that the latter expansion may be driven primarily by dynamical
effects such as compression/decompression.Comment: 12 pages including 4 postscript figure
Effect of interleukin-6 receptor blockade on surrogates of vascular risk in rheumatoid arthritis: MEASURE, a randomised, placebo-controlled study
Objectives The interleukin-6 receptor (IL-6R) blocker tocilizumab (TCZ) reduces inflammatory disease activity in rheumatoid arthritis (RA) but elevates lipid concentrations in some patients. We aimed to characterise the impact of IL-6R inhibition on established and novel risk factors in active RA.
Methods Randomised, multicentre, two-part, phase III trial (24-week double-blind, 80-week open-label), MEASURE, evaluated lipid and lipoprotein levels, high-density lipoprotein (HDL) particle composition, markers of coagulation, thrombosis and vascular function by pulse wave velocity (PWV) in 132 patients with RA who received TCZ or placebo.
Results Median total-cholesterol, low-density lipoprotein-cholesterol (LDL-C) and triglyceride levels increased in TCZ versus placebo recipients by week 12 (12.6% vs 1.7%, 28.1% vs 2.2%, 10.6% vs â1.9%, respectively; all p<0.01). There were no significant differences in mean small LDL, mean oxidised LDL or total HDL-C concentrations. However, HDL-associated serum amyloid A content decreased in TCZ recipients. TCZ also induced reductions (<30%) in secretory phospholipase A2-IIA, lipoprotein(a), fibrinogen and D-dimers and elevation of paraoxonase (all p<0.0001 vs placebo). The ApoB/ApoA1 ratio remained stable over time in both groups. PWV decreases were greater with placebo than TCZ at 12â
weeks (adjusted mean difference 0.79â
m/s (95% CI 0.22 to 1.35; p=0.0067)).
Conclusions These data provide the first detailed evidence for the modulation of lipoprotein particles and other surrogates of vascular risk with IL-6R inhibition. When compared with placebo, TCZ induced elevations in LDL-C but altered HDL particles towards an anti-inflammatory composition and favourably modified most, but not all, measured vascular risk surrogates. The net effect of such changes for cardiovascular risk requires determination.</p
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