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Objectives: We previously reported identifying three categories of HPV16-positive head and neck tumors based on The Cancer Genome Atlas (TCGA) RNA and DNA sequence data. Category 1 had truly integrated HPV16 genomes, category 2 had simple episomal genomes, and category 3 had novel episomes that were a hybrid between viral and human DNA. Using our categorization, we investigated in this study survival of patients with integrated HPV16 tumors versus patients with episomal HPV16 tumors.Materials and Methods: The TCGA RNA-Seq sequence reads were used to quantify HPV E2 and E7 gene expression, which was used as a marker for HPV integration.Results: The results demonstrate that integration is associated with poor survival; those patients with integrated HPV tumors fared no better than non-HPV tumors in their five-year survival. Integrated HPV in tumors was found strikingly to be prevalent in patients born earlier while episomal HPV was prevalent in patients born later. We also observed a fairly constant incidence of all HPV forms among head and neck cancer patients over the last eight years of this study (2006-2013).Conclusion: We propose our characterization of HPV integrated and episomal state is more accurate than previous studies that may have mischaracterized the hybrid HPV-human DNA episomes as integrated. The state of integrated HPV is associated with a poor clinical outcome. Results suggest that the incidence of integrated HPV among all HPV forms peaked and is decreasing. We discuss the importance of our findings for the management of HPV positive head and neck cancer. [ABSTRACT FROM AUTHOR]

Objectives: Craniopharyngiomas most commonly occupy in the sellar and suprasellar intracranial spaces. However, occasional accounts are made of infrasellar lesions. Recent endoscopic management of these tumors has challenged traditional microsurgical excision that involves more invasive transseptal or craniotomy approaches. We report a case of a recurrent nasopharyngeal-based craniopharyngioma that was completely resected using an endonasal endoscopic technique. We evaluate the efficacy of this approach in treating infrasellar lesions and its morbidity when compared to more traditional resection.Methods: A 31-year old man who presented with a recurrent nasopharyngeal craniopharyngioma underwent image-guided endoscopic endonasal resection. The complexity of the lesion, the operative techniques applied, and the patient’s outcome are described and supported with perioperative diagnostic images and intraoperative photographs.Results: Resection of this patient’s recurrent craniopharyngioma was carried to the level of bone along all aspects of the clival cavity and sphenoid sinus. Application of an image-guided system intraoperatively assisted in protection of the pituitary sella, carotid arteries, and optic nerves. The patient experienced no perioperative sequelae. He remains disease-free 1 year following resection and postoperative radiation therapy.Conclusion: Recurrent infrasellar craniopharyngiomas can be successfully managed using an image-guided endoscopic endonasal technique. This minimally invasive approach facilitated the resection of a recurrent tumor that had failed a microsurgical transseptal approach. [Copyright &y& Elsevier]

Podcasts have emerged as an efficient method for widespread delivery of educational clinical reasoning (CR) content. However, the impact of such podcasts on CR skills has not been established. We set out to determine whether exposure to expert reasoning in a podcast format leads to enhanced CR skills. This is a pseudo-randomized study of third-year medical students (MS3) to either a control group (n=22) of pre-established online CR modules, or intervention group (n=26) with both the online modules and novel CR podcasts. The podcasts were developed from four "clinical unknown" cases presented to expert clinician educators. After completing these assignments in weeks 1–2, weekly history and physical (H&P) notes were collected and graded according to the validated IDEA rubric between weeks 3–7. A longitudinal regression model was used to compare the H&P IDEA scores over time. Usage and perception of the podcasts was also assessed via survey data. Ninety control and 128 intervention H&Ps were scored. There was no statistical difference in the change of average IDEA scores between intervention (0.92, p=0.35) and control groups (−0.33, p=0.83). Intervention participants positively received the podcasts and noted increased discussion of CR principles from both their ward (3.1 vs. 2.4, p=0.08) and teaching (3.2 vs. 2.5, p=0.05) attendings. This is the first objective, pseudo-randomized assessment of CR podcasts in undergraduate medical education. While we did not demonstrate significant improvement in IDEA scores, our data show that podcasts are a well-received tool that can prime learners to recognize CR principles. [ABSTRACT FROM AUTHOR]

We determined methane (CH4) emissions from Alaska using airborne measurements from the Carbon Arctic Reservoirs Vulnerability Experiment (CARVE). Atmospheric sampling was conducted between May and September 2012 and analyzed using a customized version of the polar weather research and forecast model linked to a Lagrangian particle dispersion model (stochastic timeinverted Lagrangian transport model). We estimated growing season CH4 fluxes of 8 ± 2 mg CH4.m-2-d-1 averaged over all of Alaska, corresponding to fluxes from wetlands of 56+22-13 mg CH4-m-2-d-1 if we assumed that wetlands are the only source from the land surface (all uncertainties are 95% confidence intervals from a bootstrapping analysis). Fluxes roughly doubled from May to July, then decreased gradually in August and September. Integrated emissions totaled 2.1 ± 0.5 Tg CH4 for Alaska from May to September 2012, close to the average (2.3; a range of 0.7 to 6 Tg CH4) predicted by various land surface models and inversion analyses for the growing season. Methane emissions from boreal Alaska were larger than from the North Slope; the monthly regional flux estimates showed no evidence of enhanced emissions during early spring or late fall, although these bursts may be more localized in time and space than can be detected by our analysis. These results provide an important baseline to which future studies can be compared. [ABSTRACT FROM AUTHOR]

L-band radiometer brightness temperature measurements of a saltwater pond were made as a function of salinity and temperature. A precision L-band radiometer with stability better than 0.1 K per day was used for these measurements. The L-band measurements are In good agreement with three dielectric constant models over a temperature range from 8°C to 32°C and a salinity range from 25-40 psu. Based on this experiment, these dielectric models will provide an excellent basis for the algorithm development and design of the future National Aeronautics and Space Administration Aquarius sateffite mission. [ABSTRACT FROM AUTHOR]

Background: Medical educators need valid, reliable, and efficient tools to assess evidence-based medicine (EBM) knowledge and skills. Available EBM assessment tools either do not assess skills or are laborious to grade.Objective: To validate a multiple-choice-based EBM test-the Resident EBM Skills Evaluation Tool (RESET).Design: Cross-sectional study.Participants: A total of 304 medicine residents from five training programs and 33 EBM experts comprised the validation cohort.Main Measures: Internal reliability, item difficulty, and item discrimination were assessed. Construct validity was assessed by comparing mean total scores of trainees to experts. Experts were also asked to rate importance of each test item to assess content validity.Key Results: Experts had higher total scores than trainees (35.6 vs. 29.4, P < 0.001) and also scored significantly higher than residents on 11/18 items. Cronbach's alpha was 0.6 (acceptable), and no items had a low item-total correlation. Item difficulty ranged from 7 to 86%. All items were deemed "important" by > 50% of experts.Conclusions: The proposed EBM assessment tool is a reliable and valid instrument to assess competence in EBM. It is easy to administer and grade and could be used to guide and assess interventions in EBM education. [ABSTRACT FROM AUTHOR]

Background: The National Academies of Sciences report Improving Diagnosis in Healthcare highlighted the need for better training in medical decision-making, but most medical schools lack formal education in clinical reasoning. Methods: We conducted a pseudo-randomized and controlled study to evaluate the impact of a clinical reasoning curriculum in an internal medicine clerkship. Students in the intervention group completed six interactive online modules focused on reasoning concepts and a skills-based workshop. We assessed the impact of the curriculum on clinical reasoning knowledge and skills and perception of education by evaluating: (1) performance on a clinical reasoning concept quiz, (2) demonstration of reasoning in hospital admission notes, and (3) awareness of attending physician utilization of clinical reasoning concepts. Results: Students in the intervention group demonstrated superior performance on the clinical reasoning knowledge quiz (67% vs. 54%, p < 0.001). Students in the intervention group demonstrated superior written reasoning skills in the data synthesis (2.3 vs. 2.0, p = 0.02) and diagnostic reasoning (2.2 vs. 1.9, p = 0.02) portions of their admission notes, and reported more discussion of clinical reasoning by their attending physicians. Conclusions: Exposure to a clinical reasoning curriculum was associated with superior reasoning knowledge and superior written demonstration of clinical reasoning skills by third-year medical students on an internal medicine clerkship. [ABSTRACT FROM AUTHOR]

Background Best practices for faculty development programs include longitudinal, practice-based formats incorporating experiential learning with opportunities for reflection and community building. Peer coaching for faculty development provides personalized, learner-centered, work-based learning. Implementation of traditional 1-on-1 peer coaching programs is challenging due to time, logistics, and methodological barriers. Objective We sought to improve observation and reflection skills and to expand personal teaching practices of clinician educators. Methods In 2016, we developed and evaluated an innovative “1-to-many” peer-coaching model utilizing large group review of video-recorded teaching encounters. Forty-three clinician-educator faculty in general internal medicine at the University of Pittsburgh attended at least 1 of 6 sessions between February and August 2016. Sessions were moderated by a master facilitator who guided direct observation of, and reflection on, observed teaching and highlighted efficacious teaching methods. The study evaluated the acceptability and efficacy of this novel faculty development program qualitatively, with semistructured, postcurriculum telephone interviews with 20 participating faculty. Results All respondents stated that they would continue to attend faculty development sessions and would recommend them to others. The most frequently cited advantages included exposure to new teaching strategies, direct feedback, safe environment, community of practice, and growth mind-set, yet barriers emerged, such as discomfort reviewing video, difficulty giving feedback across hierarchy, and initial skepticism. None described the curriculum as critical or unsafe. Most reported increased self-reflection and adoption of new teaching behaviors. Conclusions This peer-coaching, video-based faculty development program was well received, feasible, and effective in changing self-reported teaching attitudes and practices. [ABSTRACT FROM AUTHOR]

Arctic terrestrial ecosystems are major global sources of methane (CH4); hence, it is important to understand the seasonal and climatic controls on CH4 emissions from these systems. Here, we report year-round CH4 emissions from Alaskan Arctic tundra eddy flux sites and regional fluxes derived from aircraft data. We find that emissions during the cold season (September to May) account for ≥50% of the annual CH4 flux, with the highest emissions from noninundated upland tundra. A major fraction of cold season emissions occur during the "zero curtain" period, when subsurface soil temperatures are poised near 0 °C. The zero curtain may persist longer than the growing season, and CH4 emissions are enhanced when the duration is extended by a deep thawed layer as can occur with thick snow cover. Regional scale fluxes of CH4 derived from aircraft data demonstrate the large spatial extent of late season CH4 emissions. Scaled to the circumpolar Arctic, cold season fluxes from tundra total 12 ± 5 (95% confidence interval) Tg CH4 y-1, ~25% of global emissions from extratropical wetlands, or ~6% of total global wetland methane emissions. The dominance of late-season emissions, sensitivity to soil environmental conditions, and importance of dry tundra are not currently simulated in most global climate models. Because Arctic warming disproportionally impacts the cold season, our results suggest that higher cold-season CH4 emissions will result from observed and predicted increases in snow thickness, active layer depth, and soil temperature, representing important positive feedbacks on climate warming. [ABSTRACT FROM AUTHOR]

The design, error budget, and preliminary test results of a 50-56-GHz synthetic aperture radiometer demonstration system are presented. The instrument consists of a fixed 24-element array of correlation interferometers and is capable of producing calibrated images with 1° spatial resolution within a 17° wide field of view. This system has been built to demonstrate a performance and a design which can be scaled to a much larger geostationary Earth imager. As a baseline, such a system would consist of about 300 elements and would be capable of providing contiguous full hemispheric images of the Earth with 1 K of radiometric precision and 50-km spatial resolution. An error budget is developed around this goal and then tested with the demonstrator system. Errors are categorized as either scaling (i.e., complex gain) or additive (noise and bias) errors. Sensitivity to gain and/or phase error is generally proportional to the magnitude of the expected visibility, which is high only in the shortest baselines of the array, based on model simulations of the Earth as viewed from geostationary Earth orbit. Requirements range from approximately 0.5% and 0.3° of amplitude and phase uncertainty, respectively, for the closest spacings at the center of the array, to about 4% and 2.5° for the majority of the array. The latter requirements are demonstrated with our instrument using relatively simple references and antenna models, and by relying on the intrinsic stability and efficiency of the system. The 0.5% requirement (for the short baselines) is met by measuring the detailed spatial response (e.g., on the antenna range) and by using an internal noise diode reference to stabilize the response. This result suggests a hybrid image synthesis algorithm in which long baselines are processed by a fast Fourier transform and the short baselines are processed by a more precise (G-matrix) algorithm which can handle small anomalies among antenna and receiver responses. Visibility biases and other additive errors must be below about 1.5 mK on average, regardless of baseline. The bias requirement is largely met with a phase-shifting scheme applied to the local oscillator distribution of our demonstration system. Low mutual coupling among the horn antennas of our design is also critical to minimize the biases caused by crosstalk of receiver noise. Performance is validated by a three-way comparison between interference fringes measured on the antenna range, solar transit observations, and the system model. [ABSTRACT FROM AUTHOR]

Data were acquired by the Passive and Active Land S-band airborne sensor (PALS) during the 1999 Southern Great Plains (SGP99) experiment in Oklahoma to study remote sensing of soil moisture in vegetated terrain using low-frequency microwave radiometer and radar measurements. The PALS instrument measures radiometric brightness temperature and radar backscatter at L- and S-band frequencies with multiple polarizations and approximately equal spatial resolutions. The data acquired during SGP99 provide information on the sensitivities of muitichannel low-frequency passive and active measurements to soil moisture for vegetation conditions including bare, pasture, and crop surface cover with field-averaged vegetation water contents mainly in the 0-2.5 kg m[sup -2] range. Precipitation occurring during the experiment provided an opportunity to observe wetting and drying surface conditions. Good correlations with soil moisture were observed in the radiometric channels. The 1.41-GHz horizontal-polarization channel showed the greatest sensitivity to soil moisture over the range of vegetation observed. For the fields sampled, a radiometric soil moisture retrieval accuracy of 2.3% volumetric was obtained. The radar channels showed significant correlation with soil moisture for some individual fields, with greatest sensitivity at 1.26-GHz vertical copolarized channel. However, variability in vegetation cover degraded the radar correlations for the combined field data. Images generated from data collected on a sequence of flight lines over the watershed region showed similar patterns of soil moisture change in the radiometer and radar responses. This indicates that under vegetated conditions for which soil moisture estimates may not be feasible using current radar algorithms, the radar measurements nevertheless show a response to soil moisture change, and they can provide useful information on the spatial and temporal variability of soil moisture. An illustration of the... [ABSTRACT FROM AUTHOR]