1,073 research outputs found
Giant Fluctuations of Coulomb Drag in a Bilayer System
We have observed reproducible fluctuations of the Coulomb drag, both as a
function of magnetic field and electron concentration, which are a
manifestation of quantum interference of electrons in the layers. At low
temperatures the fluctuations exceed the average drag, giving rise to random
changes of the sign of the drag. The fluctuations are found to be much larger
than previously expected, and we propose a model which explains their
enhancement by considering fluctuations of local electron properties.Comment: 10 pages, 4 figure
Geodynamic implications for zonal and meridional isotopic patterns across the northern Lau and North Fiji Basins
We present new Sr-Nd-Pb-Hf-He isotopic data for sixty-five volcanic samples from the northern Lau and North Fiji Basin. This includes forty-seven lavas obtained from forty dredge sites spanning an east-west transect across the Lau and North Fiji basins, ten ocean island basalt (OIB)-type lavas collected from seven Fijian islands, and eight OIB lavas sampled on Rotuma. For the first time we are able to map clear north-south and east-west geochemical gradients in 87Sr/86Sr across the northern Lau and North Fiji Basins: lavas with the most geochemically enriched radiogenic isotopic signatures are located in the northeast Lau Basin, while signatures of geochemical enrichment are diminished to the south and west away from the Samoan hotspot. Based on these geochemical patterns and plate reconstructions of the region, these observations are best explained by the addition of Samoa, Rurutu, and Rarotonga hotspot material over the past 4 Ma. We suggest that underplated Samoan material has been advected into the Lau Basin over the past ∼4 Ma. As the slab migrated west (and toward the Samoan plume) via rollback over time, younger and hotter (and therefore less viscous) underplated Samoan plume material was entrained. Thus, entrainment efficiency of underplated plume material was enhanced, and Samoan plume signatures in the Lau Basin became stronger as the trench approached the Samoan hotspot. The addition of subducted volcanoes to the Cook-Austral Volcanic Lineament material, first from the Rarotonga hotspot, then followed by the Rurutu hotspot, contributes to the extreme geochemical signatures observed in the northeast Lau Basin
Emissions performance of high moisture wood fuels burned in a residential stove
A study has been made of the effect of fuel moisture content on emissions from a wood burning domestic stove. Two fuel types were studied: beech which is a hardwood, and spruce which is a softwood. The moisture contents investigated were for a freshly felled wood, a seasoned wood and a kiln dried wood. The effect of the moisture measurement method was considered using a commercial electrical conductivity probe moisture meter which was compared with laboratory analysis by drying in an oven at 105 °C. It was shown that the probe can significantly underestimate the actual moisture content in certain cases. Correlations were made of the burning rate, the Emission Factors for the formation of gaseous and particulate pollutants as a function of the moisture content. We also studied the ratio of Black Carbon to Total Carbon (BC/TC) to obtain information on the organic content of the particles. The NOₓ emissions from this type of stove were only dependent on the fuel-nitrogen content and not on the moisture content
An integrated low carbon energy solution to cooking fuel, tailored to Niger state’s rural population
Niger State (Nigeria) was selected as a case study of renewable, affordable and user friendly clean energy provision in remote areas of developing countries. Niger state has 80% of its 4.5 million population living in rural agrarian areas with low literacy rates, there is a lack of wind thus eliminating wind as widely available potential power source. Based on the assessment of the local large insolation, the type of agricultural, biomass and husbandry resources, this study selected the design of anaerobic digestion units processing mostly animal and human waste, and whose heating and power requirement would be entirely provided by solar photovoltaic/thermal to maintain optimum efficiency of the biogas production. The designs was carried out at the scale of up to 15 household demand (community scale). Volume and therefore the production of biogas maybe increased or decreased in the design considered, and local, low cost resilient material were proposed. The proposed system was costed for a community of 24 people, demonstrating the potential for clean and renewable gas production economically
Is a specialist breathlessness service more effective and cost-effective for patients with advanced cancer and their carers than standard care? Findings of a mixed-method randomised controlled trial.
BACKGROUND: Breathlessness is common in advanced cancer. The Breathlessness Intervention Service (BIS) is a multi-disciplinary complex intervention theoretically underpinned by a palliative care approach, utilising evidence-based non-pharmacological and pharmacological interventions to support patients with advanced disease. We sought to establish whether BIS was more effective, and cost-effective, for patients with advanced cancer and their carers than standard care. METHODS: A single-centre Phase III fast-track single-blind mixed-method randomised controlled trial (RCT) of BIS versus standard care was conducted. Participants were randomised to one of two groups (randomly permuted blocks). A total of 67 patients referred to BIS were randomised (intervention arm n = 35; control arm n = 32 received BIS after a two-week wait); 54 completed to the key outcome measurement. The primary outcome measure was a 0 to 10 numerical rating scale for patient distress due to breathlessness at two-weeks. Secondary outcomes were evaluated using the Chronic Respiratory Questionnaire, Hospital Anxiety and Depression Scale, Client Services Receipt Inventory, EQ-5D and topic-guided interviews. RESULTS: BIS reduced patient distress due to breathlessness (primary outcome: -1.29; 95% CI -2.57 to -0.005; P = 0.049) significantly more than the control group; 94% of respondents reported a positive impact (51/53). BIS reduced fear and worry, and increased confidence in managing breathlessness. Patients and carers consistently identified specific and repeatable aspects of the BIS model and interventions that helped. How interventions were delivered was important. BIS legitimised breathlessness and increased knowledge whilst making patients and carers feel 'not alone'. BIS had a 66% likelihood of better outcomes in terms of reduced distress due to breathlessness at lower health/social care costs than standard care (81% with informal care costs included). CONCLUSIONS: BIS appears to be more effective and cost-effective in advanced cancer than standard care. TRIAL REGISTRATION: RCT registration at ClinicalTrials.gov NCT00678405 (May 2008) and Current Controlled Trials ISRCTN04119516 (December 2008).The study was supported by the following funders: NIHR Research for Patient Benefit (for Phase III RCT funding); Macmillan Cancer Support (MF’s post-doctoral fellowship); The Gatsby Foundation for the initial funding of BIS; and AT Prevost was supported by the National Institute for Health Research (NIHR) Biomedical Research Centre at Guy’s and St Thomas’ NHS Foundation Trust and King’s College London. The study sponsor was CUHNFT.This is the final published version. It first appeared at http://www.biomedcentral.com/1741-7015/12/194
Evidence for a broadly distributed Samoan-plume signature in the northern Lau and North Fiji Basins
Author Posting. © American Geophysical Union, 2014. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 15 (2014): 986–1008, doi:10.1002/2013GC005061.Geochemical enrichment of lavas in the northern Lau Basin may reflect the influx of Samoan-plume mantle into the region. We report major and trace element abundances and He-Sr-Nd-Hf-Pb-isotopic measurements for 23 submarine volcanic glasses covering 10 locations in the northern Lau and North Fiji Basins, and for three samples from Wallis Island, which lies between Samoa and the Lau Basin. These data extend the western limit of geochemical observations in the Basins and improve the resolution of North-South variations in isotopic ratios. The Samoan hot spot track runs along the length of the northern trace of the Lau and North Fiji Basins. We find evidence for a Samoan-plume component in lavas as far West as South Pandora Ridge (SPR), North Fiji Basin. Isotopic signatures in SPR samples are similar to those found in Samoan Upolu shield lavas, but show a slight shift toward MORB-like compositions. We explain the origin of the enriched signatures by a model in which Samoan-plume material and ambient depleted mantle undergo decompression melting during upwelling after transiting from beneath the thick Pacific lithosphere to beneath the thin lithosphere in the northern Lau and North Fiji Basins. Other lavas found in the region with highly depleted isotopic signatures may represent isolated pockets of depleted mantle in the basins that evaded this enrichment process. We further find that mixing between the two components in our model, a variably degassed high-3He/4He Samoan component and depleted MORB, can explain the diversity among geochemical data from the northern Lau Basin.M.G.J.
acknowledges support from NSF
grants OCE-1061134, OCE-1153894,
and EAR-1145202 and J.B.T.
acknowledges support from the
French Agence Nationale de la
Recherche (grant ANR-10-BLANC-0603
M&Ms—Mantle Melting—Measurements,
Models, Mechanisms).2014-10-1
New Experimental Limits on Macroscopic Forces Below 100 Microns
Results of an experimental search for new macroscopic forces with Yukawa
range between 5 and 500 microns are presented. The experiment uses 1 kHz
mechanical oscillators as test masses with a stiff conducting shield between
them to suppress backgrounds. No signal is observed above the instrumental
thermal noise after 22 hours of integration time. These results provide the
strongest limits to date between 10 and 100 microns, improve on previous limits
by as much as three orders of magnitude, and rule out half of the remaining
parameter space for predictions of string-inspired models with low-energy
supersymmetry breaking. New forces of four times gravitational strength or
greater are excluded at the 95% confidence level for interaction ranges between
200 and 500 microns.Comment: 25 Pages, 7 Figures: Minor Correction
Geochemical evidence in the northeast Lau Basin for subduction of the Cook-Austral volcanic chain in the Tonga Trench
Author Posting. © American Geophysical Union, 2016. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry, Geophysics, Geosystems 17 (2016): 1694–1724, doi:10.1002/2015GC006237.Lau Basin basalts host an array of geochemical signatures that suggest incorporation of enriched mantle source material often associated with intraplate hotspots, but the origin of these signatures remain uncertain. Geochemical signatures associated with mantle material entrained from the nearby Samoan hotspot are present in northwest Lau Basin lavas, and subducted seamounts from the Louisville hotspot track may contribute geochemical signatures to the Tonga Arc. However, lavas in the northeast Lau Basin (NELB) have unique enriched geochemical signatures that cannot be related to these hotspots, but can be attributed to the subduction of seamounts associated with the Cook-Austral volcanic lineament. Here we present geochemical data on a new suite of NELB lavas—ranging in 40Ar/39Ar age from 1.3 Ma to 0.365 ka—that have extreme signatures of geochemical enrichment, including lavas with the highest 206Pb/204Pb (19.580) and among the lowest 143Nd/144Nd (0.512697) encountered in the Lau Basin to date. These signatures are linked to the canonical EM1 (enriched mantle 1) and HIMU (high-μ = 238U/204Pb) mantle end-members, respectively. Using a plate reconstruction model, we show that older portions of the traces of two of the Cook-Austral hotspots that contributed volcanism to the Cook-Austral volcanic lineament—the Rarotonga and Rurutu hotspots—were potentially subducted in the Tonga Trench beneath the NELB. The geochemical signatures of the Rarotonga, Rurutu, and Samoan hotspots provide a compelling match to the extreme geochemical components observed in the new NELB lavas.NSF. Grant Number OCE-1153894, EAR-1347377, EAR-1145202, and EAR-1348082;
French Agence Nationale de la Recherche Grant Number: ANR-10-BLANC-0603;
NSF Grant Numbers: OCE-1154070, OCE-1232985, OCE-1153959 and OCE-14330972016-11-1
Nurses\u27 Alumnae Association Bulletin - Volume 6 Number 9
Remember the Relief Fund
Welcome! Miss Childs
Financial Report
Calendar of Coming Events
Lest You Forget!
Attention
Review of the Alumnae Association Meetings
Institutional Staff Nurses\u27 Section
Report of Staff Activities - 1947-1948
Private Duty Section
The White Haven Division
Barton Memorial Division
Remember the Relief Fund
Student Nurses\u27 Activities
Jefferson Scores Again
The Clara Melville Scholarship Fund
Interesting Activities of the Nurses\u27 Home Committee of the Women\u27s Board
Exclusive for Nurses
Changes in the Maternity Division
Gray Lady Musical Therapy Service
Memorial Service Honoring Mrs. Bessie Dobson Altemus
The Blood Donor Center
The Hospital Pharmacy
Medical College News
Remember the Relief Fund
Administrative Staff and Faculty of the School of Nursing
Streptomycin
Changes in the Staff at Jefferson Hospital
Care of the Thoracic Surgical Patient
Miscellaneous Items
Marriages
New Arrivals
Deaths
The Bulletin Committee
Attention, Alumnae
New Addresse
Optimization of the design of OMNIS, the observatory of multiflavor neutrinos from supernovae
A Monte Carlo code has been developed to simulate the operation of the
planned detectors in OMNIS, a supernova neutrino observatory. OMNIS will detect
neutrinos originating from a core collapse supernova by the detection of
spalled neutrons from Pb- or Fe-nuclei. This might be accomplished using
Gd-loaded liquid scintillator. Results for the optimum configuration for such
modules with respect to both neutron detection efficiency and cost efficiency
are presented. Careful consideration has been given to the expected levels of
radioactive backgrounds and their effects. The results show that the amount of
data to be processed by a software trigger can be reduced to the <10kHz region
and a neutron, once produced in the detector, can be detected and identified
with an efficiency of >30%.Comment: Elsevier preprint; 29 pages, 23 figure
- …