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Introduction: Continued smoking by cancer patients causes adverse cancer treatment outcomes, but few patients receive evidence-based smoking cessation as a standard of care.
Aim: To evaluate practical strategies to promote wide-scale dissemination and implementation of evidence-based tobacco cessation services within state cancer centers.
Methods: A Collaborative Learning Model (CLM) for Quality Improvement was evaluated with three community oncology practices to identify barriers and facilitate practice change to deliver evidence-based smoking cessation treatments to cancer patients using standardized assessments and referrals to statewide smoking cessation resources. Patients were enrolled and tracked through an automated data system and received follow-up cessation support post-enrollment. Monthly quantitative reports and qualitative data gathered through interviews and collaborative learning sessions were used to evaluate meaningful quality improvement changes in each cancer center.
Results: Baseline practice evaluation for the CLM identified the lack of tobacco use documentation, awareness of cessation guidelines, and awareness of services for patients as common barriers. Implementation of a structured assessment and referral process demonstrated that of 1,632 newly registered cancer patients,1,581 (97%) were screened for tobacco use. Among those screened, 283 (18%) were found to be tobacco users. Of identified tobacco users, 207 (73%) were advised to quit. Referral of new patients who reported using tobacco to an evidence-based cessation program increased from 0% at baseline across all three cancer centers to 64% (range = 30%–89%) during the project period.
Conclusions: Implementation of quality improvement learning collaborative models can dramatically improve delivery of guideline-based tobacco cessation treatments to cancer patients.
Introduction: The emergence of electronic cigarettes (ECs) has become a growing phenomenon that has sharply split opinion among the public health community, physicians, and lawmakers.
Aims: We sought to determine chest physician perceptions regarding ECs.
Methods: We conducted a web-based survey of 18,000 American College of Chest Physician (CHEST) members to determine health care provider experiences with EC users and to characterise provider perceptions regarding ECs.
Results/Findings: There were 994 respondents. Eighty-eight per cent reported that patients had asked their opinion of ECs, and 31% reported EC use among at least 10% of their patients. More disagreed than agreed (41% vs. 21%) that patients could improve their health by switching from tobacco smoking to daily EC use. Respondents were split on whether ECs promote tobacco cessation (32% agree vs. 33% disagree).
Conclusions: Current perceptions of ECs are variable among providers. More than 1/3 of respondents felt that EC's could be used for smoking cessation for smokers who failed prior quit attempts with approved therapies. However, many respondents were not convinced that ECs will reduce harms from tobacco use. There is an urgent need to generate additional high quality scientific data regarding ECs to inform chest physicians, health professionals, and the general public.
New radiocarbon calibration curves, IntCal04 and Marine04, have been constructed and internationally ratified to replace the terrestrial and marine components of IntCal98. The new calibration data sets extend an additional 2000 yr, from 0–26 cal kyr BP (Before Present, 0 cal BP = AD 1950), and provide much higher resolution, greater precision, and more detailed structure than IntCal98. For the Marine04 curve, dendrochronologically-dated tree-ring samples, converted with a box diffusion model to marine mixed-layer ages, cover the period from 0–10.5 cal kyr BP. Beyond 10.5 cal kyr BP, high-resolution marine data become available from foraminifera in varved sediments and U/Th-dated corals. The marine records are corrected with site-specific 14C reservoir age information to provide a single global marine mixed-layer calibration from 10.5–26.0 cal kyr BP. A substantial enhancement relative to IntCal98 is the introduction of a random walk model, which takes into account the uncertainty in both the calendar age and the 14C age to calculate the underlying calibration curve (Buck and Blackwell, this issue). The marine data sets and calibration curve for marine samples from the surface mixed layer (Marine04) are discussed here. The tree-ring data sets, sources of uncertainty, and regional offsets are presented in detail in a companion paper by Reimer et al. (this issue).
The first meeting of the IntCal04 working group took place at Queen's University Belfast from April 15 to 17, 2002. The participants are listed as co-authors of this report. The meeting considered criteria for the acceptance of data into the next official calibration dataset, the importance of including reliable estimates of uncertainty in both the radiocarbon ages and the cal ages, and potential methods for combining datasets. This preliminary report summarizes the criteria that were discussed, but does not yet give specific recommendations for inclusion or exclusion of individual datasets.
We increase the number of remote halo tracers by using blue horizontal branch (BHB) stars out to Galactocentric distances of 130 kpc. We use SDSS EDR photometry and the VLT to detect 16 BHB stars at Galactocentric distances 70 <r < 130 kpc, and to measure their radial velocities. We find the mass of the Milky Way is M = 1.7+3.0–0.6 × 1012M⊙. When completed this survey will: (i) substantially reduce the errors in the total mass and extent of the Milky Way halo, and (ii) map the velocity space in a hitherto unexplored region of the halo.
The binary X-ray source GX 1 + 4 was observed during a balloon flight in 1986, November. The source was in a relatively high intensity state. Time analysis of the data shows that the pulsation period was 111.8 ± 1.0 s indicating that one or more episodes of spin-down occurred between 1980 and 1986. Folded pulse profiles are very broad with an indication of a notch at the peak. Evidence has been found for a correlation between hard X-ray intensity and phase of the proposed 304 day orbital period. The time averaged intensity since 1980 is an order of magnitude lower than during the 1970’s. A survey of the post 1980 data shows that several reversals of the period derivative have occurred. Spin-up at the rates typical of the 1970’s has been followed by a dramatic spin-down episode with dP/dt>2.4 × 10−7 s/s.
The IntCal09 and Marine09 radiocarbon calibration curves have been revised utilizing newly available and updated data sets from 14C measurements on tree rings, plant macrofossils, speleothems, corals, and foraminifera. The calibration curves were derived from the data using the random walk model (RWM) used to generate IntCal09 and Marine09, which has been revised to account for additional uncertainties and error structures. The new curves were ratified at the 21st International Radiocarbon conference in July 2012 and are available as Supplemental Material at www.radiocarbon.org. The database can be accessed at http://intcal.qub.ac.uk/intcal13/.
The Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project will test the overarching hypothesis that an active hydrological system exists beneath a West Antarctic ice stream that exerts a major control on ice dynamics, and the metabolic and phylogenetic diversity of the microbial community in subglacial water and sediment. WISSARD will explore Subglacial Lake Whillans (SLW, unofficial name) and its outflow toward the grounding line where it is thought to enter the Ross Ice Shelf seawater cavity. Introducing microbial contamination to the subglacial environment during drilling operations could compromise environmental stewardship and the science objectives of the project, consequently we developed a set of tools and procedures to directly address these issues. WISSARD hot water drilling efforts will include a custom water treatment system designed to remove micron and sub-micron sized particles (biotic and abiotic), irradiate the drilling water with germicidal ultraviolet (UV) radiation, and pasteurize the water to reduce the viability of persisting microbial contamination. Our clean access protocols also include methods to reduce microbial contamination on the surfaces of cables/hoses and down-borehole equipment using germicidal UV exposure and chemical disinfection. This paper presents experimental data showing that our protocols will meet expectations established by international agreement between participating Antarctic nations.
We are developing a purely commensal survey experiment for fast (<5 s) transient radio sources. Short-timescale transients are associated with the most energetic and brightest single events in the Universe. Our objective is to cover the enormous volume of transients parameter space made available by ASKAP, with an unprecedented combination of sensitivity and field of view. Fast timescale transients open new vistas on the physics of high brightness temperature emission, extreme states of matter and the physics of strong gravitational fields. In addition, the detection of extragalactic objects affords us an entirely new and extremely sensitive probe on the huge reservoir of baryons present in the IGM. We outline here our approach to the considerable challenge involved in detecting fast transients, particularly the development of hardware fast enough to dedisperse and search the ASKAP data stream at or near real-time rates. Through CRAFT, ASKAP will provide the testbed of many of the key technologies and survey modes proposed for high time resolution science with the SKA.
The Center for Materials for Information Technology has a mission of outreach to middle school students. For the past two years our Center has run a summer research experiences for teachers (RET) program. A primary emphasis of the Center's educational outreach activities involves collaboration with a very innovative 6th to 8th grade Integrated Science (IS) curriculum based in the Center for Communication and Educational Technology at the University of Alabama. Each summer three teachers from the IS program spent ten weeks working in the Center to develop demonstrations or activities for use in their classrooms. The emphasis was on demonstrations of magnetism and magnetic materials. In addition to these activities, the teachers have also assisted in the development of Computer Aided Instructional (CAI) software for use in their science classrooms. Both the activities and the software developed this summer will be made available to all of the teachers and students participating in the IS curriculum, approximately 1400 teachers and 170,000 students.
We have explored the effects of various processing parameters on the dielectric and
electronic integrity of sol-gel derived silicate thin films and have identified several factors that strongly affect the thin film electronic properties. We find that sol-gel dielectrics can exhibit excellent dielectric integrity: viz., low interface trap densities and fairly good insulating properties approaching those of a thermally grown SiO2 film on Si.
We have investigated the electronic properties of sol-gel derived films on silicon substrates. Our investigation involves SiO2, aluminosilicate and borosili cate oxides on silicon. Seme sol-gel oxides are excellait insulators; seme sol-gel films on silicon also exhibit quite low oxide/silicon interface trap densities. We have also subjected sol-gel films on silicon to 4 Mrad(SiO2) of radiation and have found that these structures appear to be radiation hard (very little radiation induced oxide space charge or interface trap generation). Our results strongly suggest that sol-gel processing could provide insulating films for a variety of microelectronic device applications.
The creation mechanisms of Si and N dangling bond defect centers in amorphous hydrogenated silicon nitride thin films by ultra-violet (UV) illumination are investigated. The creation efficiency and density of Si centers in the N-rich films are independent of illumination temperature, strongly suggesting that the creation mechanism of the spins is electronic in nature, i.e., a charge transfer mechanism. However, our results suggest that the creation of the Si dangling bond in the Si-rich films are different. Last, we find that the creation of the N dangling-bond in N-rich films can be fit to a stretched exponential time dependence, which is characteristic of dispersive charge transport.
Stress in thin films is one of the mayor technological problems of silicon micromachining. Therefore stress reduction by a compensation method increases the technological use of a material. Three methods to obtain stress free films are investigated:
1. Stress in SiO2 and Si3N4 can be compensated by ion implantation.
2. Sandwich layers of SiO2 and Si3N4 can be made internally stress compensated by variation of the thickness ratio.
3. Polysilicon is stress reduced by appropriate doping and annealing.
The film stress is evaluated by the measurement of the bending of the substrate. Examples of processed membranes, bridges and cantilevers made of stress compensated films are given.
Nitrogen-rich amorphous silicon-nitride films a-Si1−xNx:H were prepared by glow-discharge decomposition of gas mixtures of ammonia and silane. With increasing nitrogen content the spin density, Ns, decreases from 4×1018cm−3 (x = 0.55) to 3×1017cm−3 (x = 0.67). These films were used as a gate dielectric in amorphous silicon TFTs. The TFTs are characterized by measurements of the transfer characteristics and by a transient current spectroscopy (TCS). Nitrogen-rich dielectrics with Ns<1018cm−3 have little influence on the transfer characteristic, however, they tend to have a lower sensitivity to bias stress. Using a device-quality nitride (x = 0.64) the properties of the TFTs were varied in two ways: 1) doping of the a-Si:H film with phosphine or diborane and 2) exposure of the nitride film to an oxygen plasma. The variation of the areal density of defect states, Nd, with Ec-EF suggests that the effective density of interface states, Ni, and the characteristic of undoped TFTs are determined by interface defects of the a-Si:H film. The plasma treatment introduces oxygen into a thin superficial layer of the nitride. By varying the exposure time te it is possible to change the properties of the TFTs continuously from nitride like to oxide like.
The free energy model (FEM) for bonding in a-SixNyHz alloys has been extended to include the contributions of neutral and charged Si and N defects to the free energy of mixing of the amorphous alloy. The FEM predicts that the dominant defects in N-rich alloys are N2o, N2-, and either S3+ or N2+, in contrast to the results of experimental studies that find the dominant neutral, paramagnetic defect to be Si3o. It is concluded that either the observed Si3o defects are not in thermodynamic equilibrium with the amorphous network or the N2o defects have energy levels which lie much higher in the energy gap than currently believed.
Ferroelectric BaTiO3 thin film capacitors were fabricated using different designs. Silicon wafers with an oxide layer were used as the substrates. Conductive metallic oxide of RuO2 was reactively sputtered on SiO2/Si as a bottom electrode. The BaTiO3 thin films with a thickness in the range of 150–300nm were deposited by RF magnetron sputtering. Different capacitor structures, including single layer amorphous, single layer polycrys-talline, and bi-layer amorphous on polycrystalline, were investigated in this study. The clear interface between BaTiO3 and RuO2 as demonstrated by cross-sectional scanning electron microscopy implies little interdiffusion. The DC conducticity of a film with a thickness of around 200nm was as low as 1×10−13OHgr-cm at 4V. The dielectric constant of the composite structure was controlled in a range from 30 to 130. Breakdown voltage varied from 5×105V/cm to 1×106V/cm.