6,757 research outputs found
Defect chemistry and characterization Hg(1-x)Cd(x)Te
Iodine doped single crystal samples of mercury cadmium telluride were annealed at temperatures varying from 450 C to 600 C in Hg vapor and quenched to room temperature. Hall effect measurements at 77 K on the crystals cooled to room temperature indicate the samples to be n-type after anneals at high Hg pressures whereas they turn p-type after anneals at low Hg pressures; the electron concentration increases with increase in Hg pressure. The results are explained on the basis that the crystals are saturated with (Hg,Cd)I2, with a fraction of the iodine being present as donor occupying tellurium lattice sites and a fraction being present as acceptors resulting from the iodine on tellurium lattice sites pairing with the doubly ionized native acceptor defects. The solubility of the donor species increases with increase in Hg pressure, whereas that of the acceptor species increases with decrease in Hg pressure. Equilibrium constants for the incorporation of the iodine species as well as the pairing reaction were established
Low-temperture electrostatic silicon-to-silicon seals using sputtered borosilicate glass
Silicon members are hermetically sealed to each other. Process produces no measurable deformation of silicon surfaces and is compatible with package designs of tight tolerance. Seals have been made with glass coatings in 10-mm to 20-mm thickness range without any prior annealing of coated silicon substrates
The colour-magnitude relations of ClJ1226.9+3332, a massive cluster of galaxies at z=0.89
(Abridged) The colour-magnitude relations of one of the most massive, high
redshift clusters of galaxies known have been studied. Photometry has been
measured in the V, R, I, z, F606W, F814W, J and K bands to a depth of K*+2.5
and spectroscopy confirms 27 K band selected cluster members. The V-K colours
are equivalent to a rest-frame colour of ~2700A-J, and provide a very sensitive
measure of star-formation activity. HST ACS imaging has been used to
morphologically classify the galaxies.
The cluster has a low early-type fraction compared to nearby clusters, with
only 33% of the cluster members having types E or S0. The early-type member
galaxies form a clear red-sequence in all colours. The scatter and slope of the
relations show no evolution compared to the equivalent Coma cluster relations,
suggesting the stellar populations are already very old. The normalisation of
the relations has been compared to models based on synthetic stellar
populations, and are most consistent with stellar populations forming at z>3.
Some late-type galaxies were found to lie on the red-sequence, suggesting that
they have very similar stellar populations to the early-types.
These results present a picture of a cluster in which the early-type galaxies
are all old, but in which there must be future morphological transformation of
galaxies to match the early-type fraction of nearby clusters. In order to
preserve the tight colour-magnitude relation of early-types seen in nearby
clusters, the late-type galaxies must transform their colours, through the
cessation of star-formation, before the morphological transformation occurs.
Such evolution is observed in the late-types lying on the colour-magnitude
relation.Comment: Accepted for publication in MNRAS. 14 pages, 5 figure
Influenza A virus infection and cigarette smoke impair bronchodilator responsiveness to β-adrenoceptor agonists in mouse lung.
β2-adrenoceptor agonists are the mainstay therapy for patients with asthma but their effectiveness in cigarette smoke (CS)-induced lung disease such as chronic obstructive pulmonary disease (COPD) is limited. In addition, bronchodilator efficacy of β2-adrenoceptor agonists is decreased during acute exacerbations of COPD (AECOPD), caused by respiratory viruses including influenza A. Therefore, the aim of the present study was to assess the effects of the β2-adrenoceptor agonist salbutamol (SALB) on small airway reactivity using mouse precision cut lung slices (PCLS) prepared from CS-exposed mice and from CS-exposed mice treated with influenza A virus (Mem71, H3N1). CS exposure alone reduced SALB potency and efficacy associated with decreased β2-adrenoceptor mRNA expression, and increased tumour necrosis factor α (TNFα) and interleukin-1β (IL-1β) expression. This impaired relaxation was restored by day 12 in the absence of further CS exposure. In PCLS prepared after Mem71 infection alone, responses to SALB were transient and were not well maintained. CS exposure prior to Mem71 infection almost completely abolished relaxation, although β2-adrenoceptor and TNFα and IL-1β expression were unaltered. The present study has shown decreased sensitivity to SALB after CS or a combination of CS and Mem71 occurs by different mechanisms. In addition, the PCLS technique and our models of CS and influenza infection provide a novel setting for assessment of alternative bronchodilators
A Water Maser and Ammonia Survey of GLIMPSE Extended Green Objects (EGOs)
We present the results of a Nobeyama 45-m water maser and ammonia survey of
all 94 northern GLIMPSE Extended Green Objects (EGOs), a sample of massive
young stellar objects (MYSOs) identified based on their extended 4.5 micron
emission. We observed the ammonia (1,1), (2,2), and (3,3) inversion lines, and
detect emission towards 97%, 63%, and 46% of our sample, respectively (median
rms ~50 mK). The water maser detection rate is 68% (median rms ~0.11 Jy). The
derived water maser and clump-scale gas properties are consistent with the
identification of EGOs as young MYSOs. To explore the degree of variation among
EGOs, we analyze subsamples defined based on MIR properties or maser
associations. Water masers and warm dense gas, as indicated by emission in the
higher-excitation ammonia transitions, are most frequently detected towards
EGOs also associated with both Class I and II methanol masers. 95% (81%) of
such EGOs are detected in water (ammonia(3,3)), compared to only 33% (7%) of
EGOs without either methanol maser type. As populations, EGOs associated with
Class I and/or II methanol masers have significantly higher ammonia linewidths,
column densities, and kinetic temperatures than EGOs undetected in methanol
maser surveys. However, we find no evidence for statistically significant
differences in water maser properties (such as maser luminosity) among any EGO
subsamples. Combining our data with the 1.1 mm continuum Bolocam Galactic Plane
Survey, we find no correlation between isotropic water maser luminosity and
clump number density. Water maser luminosity is weakly correlated with clump
(gas) temperature and clump mass.Comment: Astrophysical Journal, accepted. Emulateapj, 24 pages including 24
figures, plus 9 tables (including full content of online-only tables
Correlation between X-ray Lightcurve Shape and Radio Arrival Time in the Vela Pulsar
We report the results of simultaneous observations of the Vela pulsar in
X-rays and radio from the RXTE satellite and the Mount Pleasant Radio
Observatory in Tasmania. We sought correlations between the Vela's X-ray
emission and radio arrival times on a pulse by pulse basis. At a confidence
level of 99.8% we have found significantly higher flux density in Vela's main
X-ray peak during radio pulses that arrived early. This excess flux shifts to
the 'trough' following the 2nd X-ray peak during radio pulses that arrive
later. Our results suggest that the mechanism producing the radio pulses is
intimately connected to the mechanism producing X-rays. Current models using
resonant absorption of radio emission in the outer magnetosphere as a cause of
the X-ray emission are explored as a possible explanation for the correlation.Comment: 6 pages, 5 figures, accepted by Ap
HOPE: Help fOr People with money, employment, benefit or housing problems: study protocol for a randomised controlled trial
Background:
Self-harm and suicide increase in times of economic recession. Factors including job loss, austerity measures, financial difficulties and house repossession contribute to the risk. Vulnerable individuals commonly experience difficulties in navigating the benefits system and in accessing the available sources of welfare and debt advice, and this contributes to their distress. Our aim is to determine the feasibility and acceptability of a brief psychosocial intervention (the “HOPE” service) for people presenting to hospital emergency departments (ED) following self-harm or in acute distress because of financial, employment, or welfare (benefit) difficulties.
Method:
A pilot study including randomisation will be employed to determine whether it is possible to undertake a full-scale trial. Twenty people presenting to the ED who have self-harmed, have suicidal thoughts and depression and/or are in crisis and where financial, employment or benefit problems are cited as contributory factors will be asked to consent to random allocation to the intervention or control arm on a 2:1 basis. People who require secondary mental health follow-up will be excluded. Those randomised to the intervention arm will receive up to six sessions with a mental health worker who will provide practical help with financial and other problems. The mental health worker will use the motivational interviewing method in their interactions with participants. Control participants will receive one session signposting them to existing relevant support organisations. Participants will be followed up after 3 months. Participants and the mental health workers will take part in qualitative interviews to enable refinement of the intervention. The acceptability of outcome measures including the PHQ-9, GAD-7, repeat self-harm, EQ5D-5L and questions about debt, employment and welfare benefits will be explored.
Discussion:
This study will assess whether a full-scale randomised trial of this novel intervention to prevent self-harm among those distressed because of financial difficulties is feasible, including the acceptability of randomisation, potential rate of recruitment and the acceptability of outcome measures.
Trial registration:
ISRCTN5853124
Comparing open and minimally invasive surgical procedures for oesophagectomy in the treatment of cancer: the ROMIO (Randomised Oesophagectomy: Minimally Invasive or Open) feasibility study and pilot trial
Localised oesophageal cancer can be curatively treated with surgery (oesophagectomy) but the procedure is complex with a risk of complications, negative effects on quality of life and a recovery period of 6-9 months. Minimal-access surgery may accelerate recovery.The ROMIO (Randomised Oesophagectomy: Minimally Invasive or Open) study aimed to establish the feasibility of, and methodology for, a definitive trial comparing minimally invasive and open surgery for oesophagectomy. Objectives were to quantify the number of eligible patients in a pilot trial; develop surgical manuals as the basis for quality assurance; standardise pathological processing; establish a method to blind patients to their allocation in the first week post surgery; identify measures of postsurgical outcome of importance to patients and clinicians; and establish the main cost differences between the surgical approaches.Pilot parallel three-arm randomised controlled trial nested within feasibility work.Two UK NHS departments of upper gastrointestinal surgery.Patients aged ≥ 18 years with histopathological evidence of oesophageal or oesophagogastric junctional adenocarcinoma, squamous cell cancer or high-grade dysplasia, referred for oesophagectomy or oesophagectomy following neoadjuvant chemo(radio)therapy.Oesophagectomy, with patients randomised to open surgery, a hybrid open chest and minimally invasive abdomen or totally minimally invasive access.The primary outcome measure for the pilot trial was the number of patients recruited per month, with the main trial considered feasible if at least 2.5 patients per month were recruited.During 21 months of recruitment, 263 patients were assessed for eligibility; of these, 135 (51%) were found to be eligible and 104 (77%) agreed to participate, an average of five patients per month. In total, 41 patients were allocated to open surgery, 43 to the hybrid procedure and 20 to totally minimally invasive surgery. Recruitment is continuing, allowing a seamless transition into the definitive trial. Consequently, the database is unlocked at the time of writing and data presented here are for patients recruited by 31 August 2014. Random allocation achieved a good balance between the arms of the study, which, as a high proportion of patients underwent their allocated surgery (69/79, 87%), ensured a fair comparison between the interventions. Dressing patients with large bandages, covering all possible incisions, was successful in keeping patients blind while pain was assessed during the first week post surgery. Postsurgical length of stay and risk of adverse events were within the typical range for this group of patients, with one death occurring within 30 days among 76 patients. There were good completion rates for the assessment of pain at 6 days post surgery (88%) and of the patient-reported outcomes at 6 weeks post randomisation (74%).Rapid recruitment to the pilot trial and the successful refinement of methodology indicated the feasibility of a definitive trial comparing different approaches to oesophagectomy. Although we have shown a full trial of open compared with minimally invasive oesophagectomy to be feasible, this is necessarily based on our findings from the two clinical centres that we could include in this small preliminary study.Current Controlled Trials ISRCTN59036820.This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 48. See the NIHR Journals Library website for further project information
No End in Sight: Benzodiazepine Use in Older Adults in the United States
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135540/1/jgs14379_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135540/2/jgs14379.pd
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