32,257 research outputs found
Reduction of Band-to-band Tunneling in Deep-submicron CMOS Single Photon Avalanche Photodiodes
“The path of social justice”: A Human Rights History of Social Justice Education
Although not often recognized, social justice education in the U.S. is historically and philosophically tied to the twentieth century\u27s human rights initiatives. The efforts of human rights pioneers, such as those who authored the Universal Declaration of Human Rights, have indelibly shaped social justice efforts, including within education, in the U.S. Reframing social justice education in light of human rights gives clarity to and concretizes our work as social justice educators: It strengthens a vision of education as central to promoting rights and justice; it refocuses attention on a broader array of fundamental rights, and it explicitly contests our globalized and neoliberal context, a context heavily influencing educational reform
A range expanding signal conditioner
Telemetry system modifications to improve signal resolution are described. Process uses zero suppression technique which consists of subtracting known voltage from input and amplifying remainder. Schematic diagram of circuit is provided and details of operation are presented
Controls on carbon and energy exchange by a black spruce - moss ecosystem: Testing the mathematical model Ecosys with data from the BOREAS experiment
The cessation in pregnancy incentives trial (CPIT): study protocol for a randomized controlled trial
Background: Seventy percent of women in Scotland have at least one baby, making pregnancy an opportunity to help most young women quit smoking before their own health is irreparably compromised. By quitting during pregnancy their infants will be protected from miscarriage and still birth as well as low birth weight, asthma, attention deficit disorder and adult cardiovascular disease. In the UK, the NICE guidelines: 'How to stop smoking in pregnancy and following childbirth' (June 2010) highlighted that little evidence exists in the literature to confirm the efficacy of financial incentives to help pregnant smokers to quit. Its first research recommendation was to determine: Within a UK context, are incentives an acceptable, effective and cost-effective way to help pregnant women who smoke to quit?
<p/>Design and Methods: This study is a phase II exploratory individually randomised controlled trial comparing standard care for pregnant smokers with standard care plus the additional offer of financial voucher incentives to engage with specialist cessation services and/or to quit smoking during pregnancy. Participants (n=600) will be pregnant smokers identified at maternity booking who when contacted by specialist cessation services agree to having their details passed to the NHS Smokefree Pregnancy Study Helpline to discuss the trial. The NHS Smokefree Pregnancy Study Helpline will be responsible for telephone consent and follow-up in late pregnancy. The primary outcome will be self reported smoking in late pregnancy verified by cotinine measurement. An economic evaluation will refine cost data collection and assess potential cost-effectiveness while qualitative research interviews with clients and health professionals will assess the level of acceptance of this form of incentive payment. Research questions What is the likely therapeutic efficacy? Are incentives potentially cost-effective? Is individual randomisation an efficient trial design without introducing outcome bias? Can incentives be introduced in a way that is feasible and acceptable?
<p/>Discussion: This phase II trial will establish a workable design to reduce the risks associated with a future definitive phase III multicentre randomised controlled trial and establish a framework to assess the costs and benefits of financial incentives to help pregnant smokers to quit
Quantifying methane and nitrous oxide emissions from the UK and Ireland using a national-scale monitoring network
The UK is one of several countries around the world that has enacted legislation to reduce its greenhouse gas emissions. In this study, we present top-down emissions of methane (CH4) and nitrous oxide (N2O) for the UK and Ireland over the period August 2012 to August 2014. These emissions were inferred using measurements from a network of four sites around the two countries. We used a hierarchical Bayesian inverse framework to infer fluxes as well as a set of covariance parameters that describe uncertainties in the system. We inferred average UK total emissions of 2.09 (1.65–2.67) Tg yr−1 CH4 and 0.101 (0.068–0.150) Tg yr−1 N2O and found our derived UK estimates to be generally lower than the a priori emissions, which consisted primarily of anthropogenic sources and with a smaller contribution from natural sources. We used sectoral distributions from the UK National Atmospheric Emissions Inventory (NAEI) to determine whether these discrepancies can be attributed to specific source sectors. Because of the distinct distributions of the two dominant CH4 emissions sectors in the UK, agriculture and waste, we found that the inventory may be overestimated in agricultural CH4 emissions. We found that annual mean N2O emissions were consistent with both the prior and the anthropogenic inventory but we derived a significant seasonal cycle in emissions. This seasonality is likely due to seasonality in fertilizer application and in environmental drivers such as temperature and rainfall, which are not reflected in the annual resolution inventory. Through the hierarchical Bayesian inverse framework, we quantified uncertainty covariance parameters and emphasized their importance for high-resolution emissions estimation. We inferred average model errors of approximately 20 and 0.4 ppb and correlation timescales of 1.0 (0.72–1.43) and 2.6 (1.9–20 3.9) days for CH4 and N2O, respectively. These errors are a combination of transport model errors as well as errors due to unresolved emissions processes in the inventory. We found the largest CH4 errors at the Tacolneston station in eastern England, which may be due to sporadic emissions from landfills and offshore gas in the North Sea
Aerosol major ion record at Mount Washington
This study examined the seasonal cycles and regional-scale meteorological controls on the chemical properties of bulk aerosols collected from 1999 to 2004 at Mount Washington, the highest peak in the northeastern United States. The concentrations of NH4+ and SO42− peaked during summer months. The pattern for aerosol NO3− was more complicated with relatively high median concentrations characterizing spring and summer months, but with major elevated events occurring during fall, winter, and spring. The seasonal relationship between NH4+ and SO42− indicated that during warmer months a mixture of (NH4)2SO4 and NH4HSO4 was present, while it was mainly the latter in winter. More acidity and higher concentrations of the major species were generally associated with winds from the southwest and west sectors. The highest (≥95th percentile) concentrations of SO42− and NH4+ were associated with air mass transport from major upwind source regions in the Midwest and along the eastern seaboard. The ionic composition and seasonal cycle observed at Mount Washington were similar to those measured at other northeastern sites, but the range and average concentrations were much lower. These differences were exaggerated during wintertime. Included in this paper are several Eulerian case studies of SO2 conversion to SO42− during transit from Whiteface Mountain, New York, to Mount Washington. The calculations suggest a gas-phase SO2 oxidation rate of ∼1–2% per hour and demonstrate the possibility of using these two sites to investigate the chemical evolution of air masses as they move from Midwestern source regions to northern New England
Filamentary Accretion Flows in the Embedded Serpens South Protocluster
One puzzle in understanding how stars form in clusters is the source of mass
-- is all of the mass in place before the first stars are born, or is there an
extended period when the cluster accretes material which can continuously fuel
the star formation process? We use a multi-line spectral survey of the southern
filament associated with the Serpens South embedded cluster-forming region in
order to determine if mass is accreting from the filament onto the cluster, and
whether the accretion rate is significant. Our analysis suggests that material
is flowing along the filament's long axis at a rate of ~30Msol/Myr (inferred
from the N2H+ velocity gradient along the filament), and radially contracting
onto the filament at ~130Msol/Myr (inferred from HNC self-absorption). These
accretion rates are sufficient to supply mass to the central cluster at a
similar rate to the current star formation rate in the cluster. Filamentary
accretion flows may therefore be very important in the ongoing evolution of
this cluster.Comment: 19 pages, 8 figures, 2 tables; accepted for publication in Ap
- …