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Background: Radiography is the initial imaging modality used to evaluate femoroacetabular impingement (FAI), and diagnostic radiographic findings are well-established. However, the prevalence of these radiographic findings in patients with hip pain is unknown. Purpose: The purpose was 3-fold: (1) to determine the overall prevalence of radiographic FAI deformities in young patients presenting with hip pain, (2) to identify the most common radiographic findings in patients with cam-type FAI, and (3) to identify the most common radiographic findings in patients with pincer-type FAI. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A geographic database was used to identify patients aged 14 to 50 years with hip pain between the years 2000 to 2016. The following were evaluated on radiographs: cam type: typical pistol grip deformity, alpha angle >55°; pincer type: crossover sign (COS), coxa profunda or protrusio acetabuli, lateral center edge angle (LCEA) ≥40°, Tönnis angle <0°; and mixed type: both cam- and pincer-type features. Posterior wall sign (PWS) and ischial spine sign (ISS) were also evaluated. The prevalence of each was determined. Descriptive statistics were performed on all radiographic variables. Results: There were 1893 patients evaluated, and 1145 patients (60.5%; 1371 hips; 374 male and 771 female; mean age, 28.8 ± 8.4 years) had radiographic findings consistent with FAI. Of these hips, 139 (10.1%) had cam type, 245 (17.9%) had pincer type, and 987 (72.0%) had mixed type. The prevalence of a pistol grip deformity and an alpha angle >55° was 577 (42.1%) and 1069 (78.0%), respectively. The mean alpha angle was 66.9°± 10.5°. The prevalence of pincer-type radiographic findings was the following: COS, 1062 (77.5%); coxa profunda, 844 (61.6%); ISS, 765 (55.8%); PWS, 764 (55.7%); Tönnis angle <0°, 312 (22.8%); LCEA ≥40°, 170 (12.4%); and protrusio acetabuli, 7 (0.5%). Conclusion: The overall prevalence of radiographic findings consistent with FAI in young patients with hip pain was 60.5%. Radiographic findings for mixed-type FAI were the most prevalent. The most common radiographic finding for cam-type FAI was an alpha angle >55°. The most common radiographic finding for pincer-type FAI was the COS. [ABSTRACT FROM AUTHOR]

Direct measurements of gaseous elemental mercury (GEM) exchanges over global ecosystems are challenging and require extensive and costly measurement systems. Here, we explore the use of atmospheric GEM concentration variability and passive samplers to assess underlying ecosystem GEM exchanges at two rural temperate forests in the northeastern United States. We find strong temporal alignments between atmospheric GEM concentration declines and ecosystem GEM deposition in spring at both forests, which followed patterns of CO 2 and suggests that ambient air GEM concentration monitoring provides a proxy measurement to assess forest GEM sinks. In fall, we observe GEM concentration increases and reversal of GEM fluxes to emissions, but with poor temporal alignments. Diel GEM concentration variability did not correspond to diel patterns of ecosystem GEM fluxes, which is driven by boundary layer dynamics with different atmospheric mixing depths during day- and nighttime. Passive samplers (PASs) deployed to measure vertical GEM gradients across six heights throughout one of the forest canopies showed excellent agreements with active measurements in detecting seasonal concentration patterns at all deployment heights. We find frequent qualitative agreement between the direction of active and PAS derived concentration gradients, but small concentration differences over small (1.3 and 4.9 m) distances prevent a quantitative comparison of methods. Furthermore, time-averaged GEM concentration gradient measurements are always biased towards stable nighttime periods, while ecosystem GEM fluxes are dominated by daytime exchanges, which results in the inability of integrated measurements such as PAS to correctly quantify forest GEM exchanges. We conclude that concentration measurements both via active and passive sampling can serve as proxies to assess underlying ecosystem GEM sinks and sources, but that the use of passive samplers to quantify GEM exchange via gradient measurements is limited due their strong nighttime biases. [Display omitted] • Seasonal declines of concentrations and exchange of GEM and CO 2 are well aligned. • Diel deviation of GEM concentration and fluxes due to atmospheric rectifier effect. • PAS and GEM concentrations may be proxies for timing of ecosystem deposition onset. • PAS-inferred exchange is limited by strong nocturnal bias of gradient measurements. [ABSTRACT FROM AUTHOR]

Stereotactic body radiation therapy (SBRT) and hypofractionation using pencil-beam scanning (PBS) proton therapy (PBSPT) is an attractive option for thoracic malignancies. Combining the advantages of target coverage conformity and critical organ sparing from both PBSPT and SBRT, this new delivery technique has great potential to improve the therapeutic ratio, particularly for tumors near critical organs. Safe and effective implementation of PBSPT SBRT/hypofractionation to treat thoracic malignancies is more challenging than the conventionally fractionated PBSPT because of concerns of amplified uncertainties at the larger dose per fraction. The NRG Oncology and Particle Therapy Cooperative Group Thoracic Subcommittee surveyed proton centers in the United States to identify practice patterns of thoracic PBSPT SBRT/hypofractionation. From these patterns, we present recommendations for future technical development of proton SBRT/hypofractionation for thoracic treatment. Among other points, the recommendations highlight the need for volumetric image guidance and multiple computed tomography–based robust optimization and robustness tools to minimize further the effect of uncertainties associated with respiratory motion. Advances in direct motion analysis techniques are urgently needed to supplement current motion management techniques. [ABSTRACT FROM AUTHOR]

Introduction: A 2014 consensus statement from the Society of Surgical Oncology and American Society for Radiation Oncology supported "no ink on tumor" as an adequate margin for breast conserving therapy (BCT). This study evaluates this statement in a multi-institution cohort., Methods: A retrospective review of BCT cases at 3 comprehensive cancer centers was performed. Women age >18 receiving BCT for T1-2 breast cancer from 2008-2012 were included. Pre-2014, all sites considered 2 mm adequate. Estimated re-excision rates using the 2014 guidelines were calculated and factors predictive of re-excision were analyzed., Results: 542 patients (545 lumpectomies) were eligible. Using a ≥2 mm margin standard, 32.8% of patients underwent re-excision compared to 14.1% after 2014 (p < 0.0001). Tumor size (p= 0.003), grade (p=0.015), and lymphovascular invasion (p=0.021) were predictive of re-excision. Patients with additional intraoperative margins excised were less likely to require reoperation (p=0.002). Local recurrence was unaffected by re-excision after mean followup of 66 months., Conclusions: The 2014 margin guidelines markedly reduce re-excision rates. There is no difference in local recurrence for patients after re-excision for a close margin versus without Powered., Competing Interests: Declaration of competing interest The authors whose names are listed have NO conflict of interest., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)