242 research outputs found

    Multiscale Structure-Property Relationships of Ultra-High Performance Concrete

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    The structure-property relationships of Ultra-High Performance Concrete (UHPC) were quantified using imaging techniques to characterize the multiscale hierarchical heterogeneities and the mechanical properties. Through image analysis the average size, percent area, nearest neighbor distance, and relative number density of each inclusion type was determined and then used to create Representative Volume Element (RVE) cubes for use in Finite Element (FE) analysis. Three different size scale RVEs at the mesoscale were found to best represent the material: the largest length scale (35 mm side length) included steel fibers, the middle length scale (0.54 mm side length) included large voids and silica sand grains, and the smallest length scale (0.04 mm side length) included small voids and unhydrated cement grains. By using three length scales of mesoscale FE modeling, the bridge of information to the macroscale cementitious material model is more physically based

    Effect of population trends in body mass index on prostate cancer incidence and mortality in the United States.

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    Concurrent with increasing prostate cancer incidence and declining prostate cancer mortality in the United States, the prevalence of obesity has been increasing steadily. Several studies have reported that obesity is associated with increased risk of high-grade prostate cancer and prostate cancer mortality, and it is thus likely that the increase in obesity has increased the burden of prostate cancer. In this study, we assess the potential effect of increasing obesity on prostate cancer incidence and mortality. We first estimate obesity-associated relative risks of low- and high-grade prostate cancer using data from the Prostate Cancer Prevention Trial. Then, using obesity prevalence data from the National Health and Nutrition Examination Survey and prostate cancer incidence data from the Surveillance, Epidemiology, and End Results program, we convert annual grade-specific prostate cancer incidence rates into incidence rates conditional on weight category. Next, we combine the conditional incidence rates with the 1980 prevalence rates for each weight category to project annual grade-specific incidence under 1980 obesity levels. We use a simulation model based on observed survival and mortality data to translate the effects of obesity trends on prostate cancer incidence into effects on disease-specific mortality. The predicted increase in obesity prevalence since 1980 increased high-grade prostate cancer incidence by 15.5% and prostate cancer mortality by between 7.0% (under identical survival for obese and nonobese cases) and 23.0% (under different survival for obese and nonobese cases) in 2002. We conclude that increasing obesity prevalence since 1980 has partially obscured declines in prostate cancer mortality

    Messages to Motivate Human Papillomavirus Vaccination: National Studies of Parents and Physicians

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    Physician communication about human papillomavirus (HPV) vaccine is a key determinant of uptake. To support physician communication, we sought to identify messages that would motivate HPV vaccination

    Announcements Versus Conversations to Improve HPV Vaccination Coverage: A Randomized Trial

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    Improving provider recommendations is critical to addressing low human papillomavirus (HPV) vaccination coverage. Thus, we sought to determine the effectiveness of training providers to improve their recommendations using either presumptive “announcements” or participatory “conversations.

    An infrared survey of brightest cluster galaxies: Paper I

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    We report on an imaging survey with the Spitzer Space Telescope of 62 brightest cluster galaxies with optical line emission. These galaxies are located in the cores of X-ray luminous clusters selected from the ROSAT All-Sky Survey. We find that about half of these sources have a sign of excess infrared emission; 22 objects out of 62 are detected at 70 microns, 18 have 8 to 5.8 micron flux ratios above 1.0 and 28 have 24 to 8 micron flux ratios above 1.0. Altogether 35 of 62 objects in our survey exhibit at least one of these signs of infrared excess. Four galaxies with infrared excesses have a 4.5/3.6 micron flux ratio indicating the presence of hot dust, and/or an unresolved nucleus at 8 microns. Three of these have high measured [OIII](5007A)/Hbeta flux ratios suggesting that these four, Abell 1068, Abell 2146, and Zwicky 2089, and R0821+07, host dusty active galactic nuclei (AGNs). 9 objects (including the four hosting dusty AGNs) have infrared luminosities greater than 10^11 L_sol and so can be classified as luminous infrared galaxies (LIRGs). Excluding the four systems hosting dusty AGNs, the excess mid-infrared emission in the remaining brightest cluster galaxies is likely related to star formation.Comment: accepted for publication in ApJ

    Why is announcement training more effective than conversation training for introducing HPV vaccination? A theory-based investigation

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    Abstract Background Improving healthcare providers’ communication about HPV vaccination is critical to increasing uptake. We previously demonstrated that training providers to use presumptive announcements to introduce HPV vaccination improved uptake, whereas training them to use participatory conversations had no effect. To understand how communication training changed provider perceptions and communication practices, we evaluated intermediate outcomes and process measures from our randomized clinical trial, with a particular focus on identifying mechanisms that might explain the announcement training’s impact. Methods In 2015, a physician educator delivered 1-h in-clinic HPV vaccination recommendation trainings at 20 primary care clinics in North Carolina serving 11,578 patients age 11 or 12. Clinics were randomized to receive training to use “announcements” that presume parents are ready to vaccinate or “conversations” that invite dialog about vaccination. Training participants were 83 HPV vaccine providers. Pre- and post-training surveys assessed constructs from the theory of planned behavior (TPB), including providers’ attitudes and subjective norms about HPV vaccination and their perceived behavioral control to recommend HPV vaccination. Surveys also assessed providers’ perceptions of the announcement and conversation communication strategies. Results Both trainings improved TPB-related constructs, including providers’ positive attitudes toward HPV vaccination, subjective norms, and perceived behavioral control to recommend the vaccine (all p < .001, Cohen’s d = .62–.90). Furthermore, in both trainings, the amount of time providers reported needing to discuss HPV vaccination with parents decreased from pre-training to 1-month follow-up (mean = 3.8 vs. 3.2 min, p = .01, d = .28). However, announcement trainings outperformed conversation trainings on other measures. For example, providers who received announcement training more often reported that the communication strategy saved them time, was easy to use, helped them promote HPV vaccination as routine care, and increased HPV vaccination coverage in their clinics (all p < .05; d = .44–.60). Conclusions Both announcement and conversation trainings improved providers’ HPV vaccine-related perceptions. However, providers viewed announcements as easier to use and more effective, which may help to explain the success of this training approach. Future provider communication interventions should consider implementation outcomes, including acceptability, alongside more traditional TPB constructs. Trial registration clinicaltrials.gov, NCT02377843 . Registered on February 27, 2015

    Quality of Physician Communication about Human Papillomavirus Vaccine: Findings from a National Survey

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    Improving the quality of physicians’ recommendations for human papillomavirus (HPV) vaccination is critical to addressing low coverage. Thus, we sought to describe HPV vaccine communication practices among primary care physicians
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