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Analysis of serai conductor material and associated integrated circuits (IC) is imperative for ensuring quality products. Currently, routine circuit testing is dominated by measurement of the optical and electrical material/device properties through final device performance and parametric testing.
Characterization of the crystal microstructure still is not considered a routine process test. Structural characterization usually is based on double-crystal rocking curves, x-ray topography, or a combination of these techniques.
Energy dispersive x-ray fluorescence (XRF) spectrometry has been used extensively for some time now to do accurate and rapid analysis of a variety of samples. Most XRF Systems today use cryogenically cooled Si(Li) detectors to obtain the resolution needed for analysis of samples containing several elements. The need for the cryogenic coolant results in these XRP systems being rather large and not readily adaptable to portable devices. Detectors that require no cooling, or at least require only cooling obtainable by electrical weans, offer a definite advantage over cryogenically cooled detectors for use in portable devices. Mercuric iodide (HgI2) detectors are one type of such room-temperature detectors. The major disadvantage of any room-temperature detector has been the poor eneygy resolution associated with them.
To describe the pattern of blood culture utilization in an academic university hospital setting.
Retrospective cohort study.
A 789-bed tertiary-care university hospital that processes 40,000+blood cultures annually.
We analyzed blood cultures collected from adult inpatients at the Hospital of the University of Pennsylvania between July 1, 2014, and June 30, 2015. Descriptive statistics and regression models were used to analyze patterns of blood culture utilization: frequency of blood cultures, use of repeat cultures following a true-positive culture, and number of sets drawn per day.
In total, 38,939 blood culture sets were drawn during 126,537 patient days (incidence rate, 307.7 sets per 1,000 patient days). The median number of blood culture sets drawn per hospital encounter was 2 (range, 1–76 sets). The median interval between blood cultures was 2 days (range, 1–71 days). Oncology services and cultures with gram-positive cocci were significantly associated with greater odds of having repeat blood cultures drawn the following day. Emergency services had the highest rate of drawing single blood-culture sets (16.9%), while oncology services had the highest frequency of drawing ≥5 blood culture sets within 24 hours (0.91%). Approximately 10% of encounters had at least 1 true-positive culture, and 89.2% of those encounters had repeat blood cultures drawn. The relative risk of a patient having repeat blood cultures was lower for those in emergency, surgery, and oncology services than for those in general medicine.
Ordering practices differed by service and culture results. Analyzing blood culture utilization can contribute to the development of guidelines and benchmarks for appropriate usage.
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.
To determine whether antimicrobial-impregnated textiles decrease the acquisition of pathogens by healthcare provider (HCP) clothing.
We completed a 3-arm randomized controlled trial to test the efficacy of 2 types of antimicrobial-impregnated clothing compared to standard HCP clothing. Cultures were obtained from each nurse participant, the healthcare environment, and patients during each shift. The primary outcome was the change in total contamination on nurse scrubs, measured as the sum of colony-forming units (CFU) of bacteria.
PARTICIPANTS AND SETTING
Nurses working in medical and surgical ICUs in a 936-bed tertiary-care hospital.
Nurse subjects wore standard cotton-polyester surgical scrubs (control), scrubs that contained a complex element compound with a silver-alloy embedded in its fibers (Scrub 1), or scrubs impregnated with an organosilane-based quaternary ammonium and a hydrophobic fluoroacrylate copolymer emulsion (Scrub 2). Nurse participants were blinded to scrub type and randomly participated in all 3 arms during 3 consecutive 12-hour shifts in the intensive care unit.
In total, 40 nurses were enrolled and completed 3 shifts. Analyses of 2,919 cultures from the environment and 2,185 from HCP clothing showed that scrub type was not associated with a change in HCP clothing contamination (P=.70). Mean difference estimates were 0.118 for the Scrub 1 arm (95% confidence interval [CI], −0.206 to 0.441; P=.48) and 0.009 for the Scrub 2 rm (95% CI, −0.323 to 0.342; P=.96) compared to the control. HCP became newly contaminated with important pathogens during 19 of the 120 shifts (16%).
Antimicrobial-impregnated scrubs were not effective at reducing HCP contamination. However, the environment is an important source of HCP clothing contamination.
Deep CCD imaging of the Serpens bipolar nebula shows it to be surrounded by molecular cloud material having spiral density structure. Polarization mapping indicates that the magnetic field in this material also exhibits spiral structure and we interpret this as the remains of the magnetically-braked collapse of a protostellar cloud. A binary star system has formed in the cloud core.
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.
We present the first quantitative attempt at reconciling the source and emplacement of granite erratics in Beacon Valley. The erratics are enigmatic because granite does not crop out in the valley and its nearest subaerial exposure is at least 10 km downstream to the east of the valley. Detailed mapping of the valley shows three types of granite erratics, which are not present in equal amounts and do not show spatial patterns. Pb isotopic and elemental compositions of the erratics eliminate the Metschel Tillite as a source and indicate they derive from the Dry Valley plutons. Our limited study tentatively ties the erratics to suites of plutons, but it does not allow a direct tie of the erratics to specific plutons because of i) the geochemical variability of the plutons and ii) the limited number of erratics that were analysed. Published data suggest the erratics provide evidence of wet-based glaciation, which covered the Dry Valleys and much of Antarctica during the mid-Miocene. Our paper also explains the problems associated with the emplacement of these erratics and the age of the massive ice in Beacon Valley.
Introduction: The Medical University of South Carolina (MUSC) hospital implemented an inpatient opt-out smoking-cessation service where smokers received a mandatory smoking-cessation consult and phone follow-up within 1-month post-discharge.
Aim: To examine predictors of patients who opted-out of bedside counselling or follow-up phone calls.
Methods: Eligible adult cigarette smokers admitted to the MUSC hospital were enrolled in the programme. Opting-out of bedside consult or follow-up calls were assessed separately using log-linear modelling where predictors included patient demographics, length of hospitalisation, insurance type, smoking history, and motivation/confidence to quit.
Results: Of the 38,758 admitted patients (February 2014–May 2015), 6,684 reported currently smoking and were automatically referred to bedside-consult. Approximately 26% of smokers made contact with the counselor, most of whom (83%) accepted the consult. Amongst patients eligible for post-discharge follow-up (n = 3485), 49% responded to the calls. Those who opted-out of the bedside-consult were mostly males (RR = 1.29). Those who did not respond to follow-up calls were younger age (RR = 1.33), with Medicaid/no insurance (RR = 1.17), and had not received a bedside consult (RR = 1.32).
Conclusions: An opt-out smoking-cessation programme was feasible and acceptable to most patients and was able to reach 65% of eligible smokers; 17% opted-out of bedside counselling; <1% asked to be removed from further phone calls.
This paper presents radiocarbon results from a single Diploastrea heliopora coral from Vanuatu that lived during the Younger Dryas climatic episode, between ca. 11,700 and 12,400 calendar yr bp. The specimen has been independently dated with multiple 230Th measurements to permit calibration of the 14C time scale. Growth bands in the coral were used to identify individual years of growth. 14C measurements were made on each year. These values were averaged to achieve decadal resolution for the 14C calibration. The relative uncertainty of the decadal 14C data was below 1% (2σ). The data are in good agreement with the existing dendrochronology and allow for high-resolution calibration for most years. Variations in the fine structure of the 14C time series preserved in this specimen demonstrate sporadic rapid increases in the Δ14C content of the surface ocean and atmosphere. Certain sharp rises in Δ14C are coincident with gaps in coral growth evidenced by several hiatuses. These may be related to rapid climatic changes that occurred during the Younger Dryas. This is the first coral calibration with decadal resolution and the only such data set to extend beyond the dendrochronology-based 14C calibration.
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).
In this paper, we review the production of radiocarbon and other radionuclides in extraterrestrial materials. This radioactivity can be produced by the effects of solar and galactic cosmic rays on solid material in space. In addition, direct implantation at the lunar surface of 14C and other radionuclides can occur. The level of 14C and other radionuclides in a meteorite can be used to determine its residence time on the Earth's surface, or “terrestrial age”. 14C provides the best tool for estimating terrestrial ages of meteorites collected in desert environments. Age control allows us to understand the time constraints on processes by which meteorites are weathered, as well as mean storage times. Third, we discuss the use of the difference in 14C/12C ratio of organic material and carbonates produced on other planetary objects and terrestrial material. These differences can be used to assess the importance of distinguishing primary material formed on the parent body from secondary alteration of meteoritic material after it lands on the earth.
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.