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OBJECTIVE The objective of this scoping review is to identify, collate, and map the evidence on simulation interprofessional education activities in any setting for the education of health professional students. INTRODUCTION Simulation interprofessional education activities comprise in-person and collaborative online learning embedded in formal curricula. Though the number of simulation interprofessional education activities has increased with the knowledge of the importance of effective interprofessional collaboration, the literature still lacks a description of the characteristics of existing activities. INCLUSION CRITERIA This scoping review will consider interprofessional education activities taking place within a simulation environment. Included papers will report on activities with two or more types of learners in health professional programs. METHODS The proposed scoping review will be conducted in accordance with the JBI methodology for scoping reviews. Databases searched will include PubMed, CINAHL, and ERIC. Results will be limited to English-language publications from 2016 to the present year. Data extraction will be performed using a purposefully developed data extraction tool. Teams of reviewers will screen abstracts and full texts of articles for potential inclusion, and decisions will be determined via consensus of two out of three reviewers. Extracted data will be presented in diagrammatic or tabular form in a manner that aligns with the objective of this scoping review. A narrative summary will accompany the tabulated and/or charted results and will describe how the results relate to the review's objective and questions, and how the results might inform future simulation interprofessional education activities in health professions education.

Purpose To develop a simplified aluminum compensator system for total body irradiation (TBI) that is easy to assemble and modify in a short period of time for customized patient treatments. Methods The compensator is composed of a combination of 0.3 cm thick aluminum bars, two aluminum T‐tracks, spacers, and metal bolts. The system is mounted onto a plexiglass block tray. The design consists of 11 fixed sectors spanning from the patient's head to feet. The outermost sectors utilize 7.6 cm wide aluminum bars, while the remaining sectors use 2.5 cm wide aluminum bars. There is a magnification factor of 5 from the compensator to the patient treatment plane. Each bar of aluminum is interconnected at each adjacent sector with a tongue and groove arrangement and fastened to the T‐track using a metal washer, bolt, and nut. Inter‐bar leakage of the compensator was tested using a water tank and diode. End‐to‐end measurements were performed with an ion chamber in a solid water phantom and also with a RANDO phantom using internal and external optically stimulated luminescent detectors (OSLDs). In‐vivo patient measurements from the first 20 patients treated with this aluminum compensator were compared to those from 20 patients treated with our previously used lead compensator system. Results The compensator assembly time was reduced to 20–30 min compared to the 2–4 h it would take with the previous lead design. All end‐to‐end measurements were within 10% of that expected. The median absolute in‐vivo error for the aluminum compensator was 3.7%, with 93.8% of measurements being within 10% of that expected. The median error for the lead compensator system was 5.3%, with 85.1% being within 10% of that expected. Conclusion This design has become the standard compensator at our clinic. It allows for quick assembly and customization along with meeting the Task Group 29 recommendations for dose uniformity.

Purpose For mobile lung tumors, four‐dimensional computer tomography (4D CT) is often used for simulation and treatment planning. Localization accuracy remains a challenge in lung stereotactic body radiation therapy (SBRT) treatments. An attractive image guidance method to increase localization accuracy is 4D cone‐beam CT (CBCT) as it allows for visualization of tumor motion with reduced motion artifacts. However, acquisition and reconstruction of 4D CBCT differ from that of 4D CT. This study evaluates the discrepancies between the reconstructed motion of 4D CBCT and 4D CT imaging over a wide range of sine target motion parameters and patient waveforms. Methods A thorax motion phantom was used to examine 24 sine motions with varying amplitudes and cycle times and seven patient waveforms. Each programmed motion was imaged using 4D CT and 4D CBCT. The images were processed to auto segment the target. For sine motion, the target centroid at each phase was fitted to a sinusoidal curve to evaluate equivalence in amplitude between the two imaging modalities. The patient waveform motion was evaluated based on the average 4D data sets. Results The mean difference and root‐mean‐square‐error between the two modalities for sine motion were −0.35 ± 0.22 and 0.60 mm, respectively, with 4D CBCT slightly overestimating amplitude compared with 4D CT. The two imaging methods were determined to be significantly equivalent within ±1 mm based on two one‐sided t tests (p

Purpose Studies have evaluated the viability of using open‐face masks as an immobilization technique to treat intracranial and head and neck cancers. This method offers less stress to the patient with comparable accuracy to closed‐face masks. Open‐face masks permit implementation of surface guided radiation therapy (SGRT) to assist in positioning and motion management. Research suggests that changes in patient facial expressions may influence the SGRT system to generate false positional corrections. This study aims to quantify these errors produced by the SGRT system due to face motion. Methods Ten human subjects were immobilized using open‐face masks. Four discrete SGRT regions of interest (ROIs) were analyzed based on anatomical features to simulate different mask openings. The largest ROI was lateral to the cheeks, superior to the eyebrows, and inferior to the mouth. The smallest ROI included only the eyes and bridge of the nose. Subjects were asked to open and close their eyes and simulate fear and annoyance and peak isocenter shifts were recorded. This was performed in both standard and SRS specific resolutions with the C‐RAD Catalyst HD system. Results All four ROIs analyzed in SRS and Standard resolutions demonstrated an average deviation of 0.3 ± 0.3 mm for eyes closed and 0.4 ± 0.4 mm shift for eyes open, and 0.3 ± 0.3 mm for eyes closed and 0.8 ± 0.9 mm shift for eyes open. The average deviation observed due to changing facial expressions was 1.4 ± 0.9 mm for SRS specific and 1.6 ± 1.6 mm for standard resolution. Conclusion The SGRT system can generate false positional corrections for face motion and this is amplified at lower resolutions and smaller ROIs. These errors should be considered in the overall tolerances and treatment plan when using open‐face masks with SGRT and may warrant additional radiographic imaging.

Previous studies have shown that moderate concentrations of Chinese tallow leaf litter can quickly reduce dissolved oxygen and pH in the aquatic environment. While these studies mostly focus on its effects on the performance of amphibians, this study focuses on determining the causes of deoxygenation and acid water. We also examined the effects of Chinese tallow litter on other water quality parameters and how changes may influence microbial communities in aquatic environments. We used laboratory and outdoor experiments to demonstrate the effects of Chinese tallow litter on aquatic chemistry. Additional laboratory studies investigated litter quality and soluble nutrients. We tested the effects of an antimicrobial agent on microbial activity in Chinese tallow litter treatments. Outdoor mesocosms were used to assess the impact of Chinese tallow and native litter monocultures on aquatic chemistry and microbial community composition. We measured water chemistry and sampled mesocosms for microbial rRNA genes. We found evidence that biological mechanisms are causing deoxygenation, while chemical mechanisms may be influencing acid water. Chinese tallow litter was of different quality, decomposed faster and leached more soluble nutrients than native species. Chinese tallow litter traits appear to have different effects on microbial activity and community composition than native litter. Our results suggest that Chinese tallow litter can have an impact on aquatic chemistry and the composition of aquatic microbial communities as it replaces native species in southern forests. The implications of our results are potential shifts in aquatic ecosystem processes.

Two end-to-end tests evaluate the accuracy of a surface-guided radiation therapy (SGRT) system (CRAD Catalyst HD) for position verification in comparison to a stereoscopic x-ray imaging system (Brainlab Exactrac ) for single-isocenter, multiple metastases stereotactic radiosurgery (SRS) using 3D polymer gel inserts.A 3D-printed phantom (Prime phantom, RTsafe PC, Athens, Greece) with two separate cylindrical polymer gel inserts were immobilized in open-face masks and treated with a single isocentric, multitarget SRS plan. Planning was done in Brainlab (Elements) to treat five metastatic lesions in one fraction, and initial setup was done using cone beam computed tomography. Positional verification was done using orthogonal X-ray imaging (Brainlab Exactrac) and/or a surface imaging system (CRAD Catalyst HD, Uppsala, Sweden), and shift discrepancies were recorded for each couch angle. Forty-two hours after irradiation, the gel phantom was scanned in a 1.5 Tesla MRI, and images were fused with the patient computed tomography data/structure set for further analysis of spatial dose distribution.Discrepancies between the CRAD Catalyst HD system and Brainlab Exactrac were 1 mm in the translational direction and 0.5° in the angular direction at noncoplanar couch angles. Dose parameters (DDose metrics for a setup with surface imaging was found to be consistent with setup using x-ray imaging, demonstrating high accuracy and reproducibility for treatment delivery. Results indicate the feasibility of using surface imaging for position verification at noncoplanar couch angles for single-isocenter, multiple-target SRS using end-to-end quality assurance (QA) testing with 3D polymer gel dosimetry.

Purpose: Monaco treatment planning system (TPS) version 5.1 uses a Monte-Carlo (MC)-based dose calculation engine. The aim of this study is to verify and compare the Monaco-based dose calculations with both Pinnacle3 collapsed cone convolution superposition (CCCS) and Eclipse anisotropic analytical algorithm (AAA) calculations. Materials and Methods: For this study, 18 previously treated lung and head-and-neck (HN) cancer patients were chosen to compare the dose calculations between Pinnacle, Monaco, and Eclipse. Plans were chosen from those that had been treated using the Elekta VersaHD or a Novalis Tx linac. All of the treated volumetric-modulated arc therapy plans used 6 MV or 10 MV photon beams. The original plans calculated with CCCS or AAA along with the recalculated ones using MC from the three TPS were exported into Velocity software for intercomparison. Results: To compare the dose calculations, Planning target volume (PTV) heterogeneity indexes and conformity indexes were calculated from the dose volume histograms (DVH) of all plans. While mean lung dose (MLD), lung V5 and V20 values were recorded for lung plans, the computed dose to parotids, brainstem, and mandible were documented for HN plans. In plan evaluation, percent differences of the above dosimetric values in Monaco computation were compared against each of the other TPS computations. Conclusion: It could be concluded through this research that there can be differences in the calculation of dose across different TPSs. Although relatively small, these differences could become apparent when compared using DVH. These differences most likely arise from the different dose calculation algorithms used in each TPS. Monaco employs the MC allowing it to have much more detailed calculations that result in it being seen as the most accurate and the gold standard.

Purpose Prognostic indices such as the Brain Metastasis Graded Prognostic Assessment have been used in clinical settings to aid physicians and patients in determining an appropriate treatment regimen. These indices are derivative of traditional survival analysis techniques such as Cox proportional hazards (CPH) and recursive partitioning analysis (RPA). Previous studies have shown that by evaluating CPH risk with a nonlinear deep neural network, DeepSurv, patient survival can be modeled more accurately. In this work, we apply DeepSurv to a test case: breast cancer patients with brain metastases who have received stereotactic radiosurgery. Methods Survival times, censorship status, and 27 covariates including age, staging information, and hormone receptor status were provided for 1673 patients by the NCDB. Monte Carlo cross-validation with 50 samples of 1400 patients was used to train and validate the DeepSurv, CPH, and RPA models independently. DeepSurv was implemented with L2 regularization, batch normalization, dropout, Nesterov momentum, and learning rate decay. RPA was implemented as a random survival forest (RSF). Concordance indices of test sets of 140 patients were used for each sample to assess the generalizable predictive capacity of each model. Results Following hyperparameter tuning, DeepSurv was trained at 32 min per sample on a 1.33 GHz quad-core CPU. Test set concordance indices of 0.7488 ± 0.0049, 0.6251 ± 0.0047, and 0.7368 ± 0.0047, were found for DeepSurv, CPH, and RSF, respectively. A Tukey HSD test demonstrates a statistically significant difference between the mean concordance indices of the three models. Conclusion Our results suggest that deep learning-based survival prediction can outperform traditional models, specifically in a case where an accurate prognosis is highly clinically relevant. We recommend that where appropriate data are available, deep learning-based prognostic indicators should be used to supplement classical statistics.

Purpose To create an open‐source visualization program that allows one to find potential cone collisions while planning intracranial stereotactic radiosurgery cases. Methods Measurements of physical components in the treatment room (gantry, cone, table, localization stereotactic radiation surgery frame, etc.) were incorporated into a script in MATLAB (MathWorks, Natick, MA) that produces three‐dimensional visualizations of the components. A localization frame, used during simulation, fully contains the patient. This frame was used to represent a safety zone for collisions. Simple geometric objects are used to approximate the simulated components. The couch is represented as boxes, the gantry head and cone are represented by cylinders, and the patient safety zone can be represented by either a box or ellipsoid. These objects are translated and rotated based upon the beam geometry and the treatment isocenter to mimic treatment. A simple graphical user interface (GUI) was made in MATLAB (compatible with GNU Octave) to allow users to pass the treatment isocenter location, the initial and terminal gantry angles, the couch angle, and the number of angular points to visualize between the initial and terminal gantry angle. Results The GUI provides a fast and simple way to discover collisions in the treatment room before the treatment plan is completed. Twenty patient arcs were used as an end‐to‐end validation of the system. Seventeen of these appeared the same in the software as in the room. Three of the arcs appeared closer in the software than in the room. This is due to the treatment couch having rounded corners, whereas the software visualizes sharp corners. Conclusions This simple GUI can be used to find the best orientation of beams for each patient. By finding collisions before a plan is being simulated in the treatment room, a user can save time due to replanning of cases.

Purpose Single‐isocenter multiple brain metastasis stereotactic radiosurgery is an efficient treatment modality increasing in clinical practice. The need to provide accurate, patient‐specific quality assurance (QA) for these plans is met by several options. This study reviews some of these options and explores the use of the Octavius 4D as a solution for patient‐specific plan quality assurance. Methods The Octavius 4D Modular Phantom (O4D) with the 1000 SRS array was evaluated in this study. The array consists of 977 liquid‐filled ion chambers. The center 5.5 cm × 5.5 cm area has a detector spacing of 2.5 mm. The ability of the O4D to reconstruct three‐dimensional (3D) dose was validated against a 3D gel dosimeter, ion chamber, and film measurements. After validation, 15 patients with 2–11 targets had their plans delivered to the phantom. The criteria used for the gamma calculation was 3%/1 mm. The portion of targets which were measurable by the phantom was countable. The accompanying software compiled the measured doses allowing each target to be counted from the measured dose distribution. Results Spatial resolution was sufficient to verify the high dose distributions characteristic of SRS. Amongst the 15 patients there were 74 targets. Of the 74 targets, 61 (82%) of them were visible on the measured dose distribution. The average gamma passing rate was 99.3% (with sample standard deviation of 0.68%). Conclusions The high resolution provided by the O4D with 1000 SRS board insert allows for very high‐resolution measurement. This high resolution in turn can allow for high gamma passing rates. The O4D with the 1000 SRS array is an acceptable method of performing quality assurance for single‐isocenter multiple brain metastasis SRS.

At the conclusion of road construction projects, an erosion control product (e.g., blankets, spray mulch) is installed to reduce soil loss and promote plant growth. Wildlife, such as snakes (suborder Serpentes), are prone to entanglement in erosion control blankets (ECBs) that contain polypropylene mesh with fused apertures. Previous reports have noted that the occurrences of entanglements are not uniform in their distribution across an ECB, but primarily occur where the edge of the mesh is exposed. We conducted an experiment to determine if modification to the installation methods of ECBs affects the likelihood of snake entanglement. We conducted entanglement trials to compare the likelihood of snake entanglement between two treatments: 1) exposed ECB edge (i.e., perimeter) and 2) buried ECB edge. Snakes were less likely to attempt to pass through the mesh on the buried edge treatment and all entanglements occurred on the exposed edge treatment. These results provide support that modification to the installation methods reduces snake entanglement in ECBs in some settings. However, we conducted our study in an experimental setting, and it should be evaluated under natural field conditions. This research can be used to inform several parties including contractors, habitat managers, and agency decision makers on additional steps that can be taken for products that fit their application needs to minimize risks to wildlife.

I n the United States, roads are prominent across the landscape, negatively impacting wildlife and ecological processes via road mortality (Brady and Richardson 2017). The extensive roadway system in the United States requires consistent maintenance that results in soil erosion potential. For example, as of August of 2019 in Texas, there were 6,739 active roadway projects, with another 6,448 projects listed to begin within the next four years (Texas Department of Transportation 2019). Despite regulatory and mitigation efforts, soil erosion and stream sedimentation are known to occur at construction sites due to exposure of the soil to environmental factors that influence erosion rates (Kaufman 2000; Benik et al. 2003). At the conclusion of construction projects, the Texas Department of Transportation (TxDOT) mandates that erosion control products (ECPs) are deployed on unpacked soil to prevent soil erosion potential and to promote plant growth (Babcock and McLaughlin 2013; Texas Department of Transportation 2018a). The TxDOT maintains an approved product list (APL) of all ECPs (ranging from mesh blankets to sprays and mulches) that can be used by contractors at the conclusion of a roadway construction project. To be placed on the APL, products must pass two performance standards: (1) protect the seedbed of an embankment or drainage channel from the loss of sediment during simulated rainfall or channel flow events, and (2) promote the establishment of warm-season, perennial vegetation …

Throughout history a great many plant species have been purposefully transported to new areas around the globe. Horticulture, the promise of new sources of plant material for industry, forage, food, and stabilization of soil are only a few of the motives for the early transcontinental exchange of plants. Many introductions have been beneficial or benign, but some plants introduced into new areas are now considered invasive and detrimentally impact the environment. Triadica sebifera (Chinese Tallowtree; Euphorbiaceae) is an excellent example of the best intentions leading to unanticipated negative effects many decades later. Native to eastern Asia and now naturalized and widespread in many tropical, subtropical, and temperate areas in the world, Chinese Tallowtree has proven to be one of the worst woody invasive plants. It is known for shading out native vegetation, capable of dominating areas following disturbance or even invading previously diverse undisturbed habitats. It is prevalent in the southern United States, especially along the Gulf Coast. Investigations into classical biological control of Chinese Tallowtree have yielded at least 2 promising candidates but have raised objections among beekeepers and beekeeping organizations who prize the quality honey produced from an abundant spring nectar flow. In this overview, we discuss Chinese Tallowtree's invasive characteristics, detrimental effects, potential use as a biomass crop, and demonstrated or potential direct and indirect effects on native and non-native pollinators. We review the current state of identification and screening of biological control agents and present 4 research topics that are would fill gaps in our knowledge of Chinese Tallowtree and pollinators. Classical biological control has the potential to reduce Chinese Tallowtree populations across the landscape, which would likely result in greater understory and tree diversity, benefitting native and exotic pollinators.

Background Interprofessional communication is fundamental to the delivery of healthcare and can be taught in medical school and other health professional schools through interprofessional education (IPE) activities. Simulation centers have become a predominant location for simulation IPE activities with infrastructure able to support high fidelity activities in a controlled environment. In this secondary analysis of a scoping review conducted on simulation-based IPE, we describe the characteristics of previously reported simulation IPE activities involving undergraduate medical students in a simulation center focused on interprofessional communication. Methods Electronic searches of PubMed, CINAHL, and ERIC databases in accordance with PRISMA-ScR guidelines were conducted to isolate relevant articles from 2016–2020. In total, 165 peer-reviewed articles met inclusion criteria and data extraction linked to four research questions was applied by one individual and the accuracy was confirmed by a second individual. A secondary analysis was performed to describe what existing approaches for simulation IPE in simulation center settings have been used to explicitly achieve interprofessional communication competencies in undergraduate medical education. A sub-dataset was developed from the original scoping review and identified 21 studies describing simulation IPE activities that took place in dedicated simulation centers, targeted the IPEC interprofessional communication domain, and involved undergraduate medical students. Results Though diverse, the majority of simulation IPE activities described high-fidelity approaches involving standardized patients and utilized assessment tools with established validity evidence in IPE activities to measure learning outcomes. A minority of simulation IPE activities were described as hybrid and utilized more than one resource or equipment for the activity and only two were longitudinal in nature. Learning outcomes were focused predominantly on modification of attitudes/perceptions and few targeted higher levels of assessment. Conclusions Educators charged with developing simulation IPE activities for medical students focused on interprofessional communication should incorporate assessment tools that have validity evidence from similar activities, target higher level learning outcomes, and leverage hybrid models to develop longitudinal simulation IPE activities. Though an ideal environment to achieve higher level learning outcomes, simulation centers are not required for meaningful simulation IPE activities.

To determine the severity of the effects on VMAT dose calculations caused by varying statistical uncertainties (SU) per control point in a Monte Carlo based treatment planning system (TPS) and to assess the impact of the uncertainty during dose volume histogram (DVH) evaluation.For this study, 13 archived patient plans were selected for recalculation. Treatment sites included prostate, lung, and head and neck. These plans were each recalculated five times with varying uncertainty levels using Elekta's Monaco Version 5.11.00 Monte Carlo Gold Standard XVMC dose calculation algorithm. The statistical uncertainty per control point ranged from 2 to 10% at intervals of 2%, while the grid spacing was set at 3 mm for all calculations. Indices defined by the RTOG describing conformity, coverage, and homogeneity were recorded for each recalculation.For all indices tested, one-way ANOVA tests failed to reject the null hypothesis that there is no significant difference between SU levels (p0.05). Using the Bland-Altman analysis method, it was determined that we can expect the indices (with the exception of CIRTOG) to be within 1% of the lowest uncertainty calculation when calculating at 4% SU per control point. Beyond that, we can expect the indices to be within 3% of the lowest uncertainty calculation.Increasing the SU per control point exponentially decreased the amount of time required for dose calculations, while creating minimal observable differences in DVHs and isodose lines.

It is important that species descriptions be accurate. This is especially true with threatened and endangered species, where the scientific literature provides context for species identification and management decisions. In 1953, Bragg documented the advertisement calls of both Southern Crawfish Frogs (Lithobates a. areolatus) and Northern Crawfish Frogs (L. a. circulosus) and concluded L. a. areolatus have lower frequency calls. One of us (M.J.L.) has long felt this observation was incorrect, because adult L. a. areolatus are smaller than L. a. circulosus, and anurans with smaller body sizes tend to produce higher, not lower, frequency calls. Bragg's observations are not only the sole comparative assessment of advertisement call characteristics of L. areolatus in the primary literature, but also represent the only assessment of the advertisement calls of any of the four species comprising the subgenus Nenirana, which consists of threatened and endangered Gopher Frogs (L. capito and L. sevosus) and Picker...

Purpose The Brainlab Elements treatment planning system utilizes distinct modules for treatment planning specific to stereotactic treatment sites including single or multiple brain lesions as well as spine. This work investigates the hypothesis that an optimization tailored specifically to spine can in fact create dosimetrically superior plans to those created in more general use treatment planning systems (TPS). Methods Ten spine patients at our institution were replanned in Brainlab Elements, Phillips Pinnacle3, and Elekta Monaco. The planning target volume (PTV) included the vertebral body (in either the thoracic or lumbar spine), pedicles, and transverse processes. In all plans, the target was prescribed 20 Gy to 95% of the PTV. Objectives for the study included D5%

Anurans often call in acoustically complex choruses, which can consist of multiple closely related species. Closely related sympatric species often differ in phenology and the acoustic properties of male advertisement calls, which, in some species, are phenotypically plastic. The tetraploid Eastern Gray Treefrog (Hyla versicolor) originates from multiple, separate hybridization events of the diploid Cope's Gray Treefrog (Hyla chrysoscelis) with now-extinct diploid anurans. The two species are visually indistinguishable, exhibit highly similar ecology and behavior, and co-occur frequently across their range. Males of these species can be distinguished from each other by the structure of their advertisement calls. Daily audio recordings and weather data were collected for five consecutive years from eight breeding sites of sympatric H. versicolor and H. chrysoscelis. We examined spatial and temporal patterns in calling phenology and responses of both species to environmental cues. Additionally, we measured three advertisement call properties to evaluate differences in call structure based on community composition. The phenologies of the two gray treefrog species were nearly identical, and the presence of the other species did not significantly affect call pulse rate or dominant frequency in either species. Chorus composition affected call duration in both species, but in H. chrysoscelis, this effect was temperature dependent. Our results indicate that while calling phenology does not contribute to reproductive isolation in sympatric gray treefrogs, modulation of phenotypically plastic call properties could affect male mating success and prezygotic reproductive isolation.

To compare the accuracy of two separate models when calculating dose distributions in patients undergoing stereotactic radiosurgery (SRS) treatment for brain cancer.For this comparison, two dose calculation algorithms were evaluated on two different treatment planning systems (TPS): Elekta's Monaco Version 5.11.00 Monte Carlo Gold Standard XVMC algorithm and Brainlab's iPlan Pencil Beam algorithm. The DICOM files of 11 patients with a total of 19 targets were exported from iPlan and then imported into Monaco to be recalculated. Using the dose distributions of the original (pencil beam/PB) and recalculated (Monte Carlo/MC) plans, four indices for plan quality were evaluated: coverage (Q), conformity index (CIRTOG), homogeneity index (HI), and gradient index (GI).There was a significant difference in the CIRTOG and HI between the two TPS calculations. However, the magnitude of these differences is often not substantial enough to cause the plan to fall outside of RTOG protocol deviation limits. Only 3 of the 19 targets had CIRTOG values which moved to a new level of deviation, and these targets were unique in terms of size (0.1 cm3).It was found that the difference between systems is often not enough to cause the plan to fall outside of RTOG protocol deviation limits. This is an indication that a PB-based treatment planning system is sufficient for the mostly homogeneous conditions of intracranial SRS planning when the target is larger than 0.1 cm3. If below 0.1 cm3, the prescribing physician may need to evaluate TPS differences.

The activity level-predation risk paradigm of community assembly is based on observable trade-offs between activity level and predation risk. Many species that live in ephemeral habitats are relatively more active, grow faster, and metamorphose sooner than those in more permanent habitats, thus enabling them to survive by escaping drying ponds. Species with high activity levels are shown to be superior competitors in temporary ponds, but are at greater risk of predation by visually cued predators. We take a comprehensive approach to testing if the activity-predation paradigm drives community assembly of a four-species guild of larval anurans through field surveys and a series of laboratory experiments quantifying their activity level, anti-predatory responses, swim performance, and escape behavior. Activity level was a good predictor of susceptibility to predation and habitat association for most species in our study, but not all species fit the pattern. Secondary anti-predator mechanisms contributed to differences in susceptibility to predation. Some species were more capable of avoiding predation through swim performance and escape behavior, thus allowing them to occupy a greater range of the water permanency continuum than was predicted by activity level alone. Because performance traits are deeply rooted, evolutionary history plays a major role in determining tadpole performance and life-history traits. Whole-organism performance traits (e.g., swim performance, escape behavior) have not generally been considered in the classic activity-predation paradigm. Our results show that accounting for individual and species-level performance reveals the understudied, yet important role of species-specific performance traits in disentangling the mechanisms driving community assembly.

Background The accuracy of stereotactic radiosurgery to multiple brain metastases with a single isocenter using high definition dynamic radiosurgery (HDRS) was evaluated to assess robustness, repeatability, and possibility of inter-institutional quality assurance amongst multiple institutions. Methods A CT simulation scan obtained from a previously treated patient was used as the data set for targeting seven brain lesions. A VMAT treatment plan was generated using Monaco and was replicated at six HDRS-capable institutions using a plan template. All institutions subsequently irradiated 3D-printed head anthropomorphic phantoms mimicking the patient’s anatomy. Three different phantoms with a point dosimeter insert, film insert, and a gel dosimeter were used. Absolute dosimetry end-to-end dosimetric accuracy as well as gamma analysis for relative dose distribution agreement analysis was used to evaluate measurement agreement with calculation. Results Point measurements averaged across all institutions using six-degree-of-freedom treatment positioning correction were within 1.2±0.5%. The average gamma passing rate in the film plane using 3D global 3D gamma analysis was 96.6±2.2% (3%/2 mm). For all targets within 4 cm of the isocenter, the 3D dosimetric gel gamma passing rate averaged across institutions was >90% (3%/2 mm). 88.0% average gamma passing rate was found for targets beyond 4 cm. The targeting accuracy of high definition dynamic radiosurgery assessed by geometrical offset of the center of dose distributions was established across multiple institutions in this study to be within 1 mm for targets within 4 cm of isocenter. Conclusions Across variations in clinical practice, comparable dosimetry and localization is possible with this treatment planning and delivery technique.

The assembly of local communities is likely to reflect the effects of local environmental factors associated with filters that act at larger spatial scales. Dissecting these multiscale effects remains a timely challenge that is particularly important for host-associated microbiomes. We investigated the relative roles of local selection (due to host species identity) and regional effects (due to water body identity) on the community structure of bacteria in the gut of tadpoles from three biogeographic areas and used graph theory and metanetwork approaches to explore and illustrate the distribution of bacteria across different ponds. The pond of origin, which represents a regional species pool of bacteria, was in general more important in shaping the gut microbiome of tadpoles than host species identity. The resulting metanetworks are modular and indicate relatively few species of bacteria occurring in more than one pond. Thus, each pond represents a relatively distinct species pool of bacteria available for community assembly of the tadpole microbiomes. Our findings indicate that microbiome community assembly in amphibian larvae, as in many other communities, is a multiscale process with important regional effects that constrain how local (i.e. host-dependent) filters act to influence microbiome community composition.

With the increasingly prominent role of stereotactic radiosurgery in radiation therapy, there is a clinical need for robust, efficient, and accurate solutions for targeting multiple sites with one patient setup. The end-to-end accuracy of high definition dynamic radiosurgery with Elekta treatment planning and delivery systems was investigated in this study.A patient-derived CT scan was used to create a radiosurgery plan to seven targets in the brain. Monaco was used for treatment planning using 5 VMAT non-coplanar arcs. Prior to delivery, 3D-printed phantoms from RTsafe were ordered including a gel phantom for 3D dosimetry, phantom with 2D film insert, and an ion chamber phantom for point dose measurement. Delivery was performed using the Elekta VersaHD, XVI cone-beam CT, and HexaPOD six degree of freedom tabletop.Absolute dose accuracy was verified within 2%. 3D global gamma analysis in the film measurement revealed 3%/2 mm passing rates95%. Gel dosimetry 3D global gamma analysis (3%/2 mm) were above 90% for all targets with the exception of one. Results were indicative of typical end-to-end accuracies (1 mm spatial uncertainty, 2% dose accuracy) within 4 cm of isocenter. Beyond 4 cm, 2 mm accuracy was found.High definition dynamic radiosurgery expands clinically acceptable stereotactic accuracy to a sphere around isocenter allowing for radiosurgery of several targets with one setup with a high degree of dosimetric precision. Gel dosimetry proved to be an essential tool for the validation of the 3D dose distributions in this technique.

Purpose While external beam radiotherapy treatment planning determines nearly every mechanical and dosimetric parameter of the linear accelerator (LINAC), the table coordinates in all three dimensions are generally unknown until initial patient setup at the LINAC. Knowing these parameters in advance could help verify the direction of patient shifts and prevent wrong‐site errors. This study aims to determine the feasibility and accuracy of table coordinate prediction for indexed immobilization devices. Methods A total of 303 table coordinates were predicted for patients on Varian and Elekta linear accelerators with immobilization devices including Orfit mask with baseplate, wingboard, breastboard and BodyFix. Predictions were made for all three spatial dimensions except for Body Fix setups due to the lack of a radiographically apparent indexing‐related landmark. Coordinates were predicted by measuring baseline table coordinates in all dimensions at specified landmark positions. Results Predictions were accurate within 2 cm for 86% of coordinates (71% within 1 cm). Table coordinates were predicted most accurately for head and neck patients with a base plate and the most difficult prediction was in the lateral direction for breastboard patients. Conclusions With proper indexing, table coordinates can be predicted with reasonable accuracy. The data suggest an action of level of 2 cm with certain exceptions for specific immobilization devices and directions.

Picoides borealis (Red-cockaded Woodpecker) is an endangered bird endemic to the Pinus (pine) ecosystems of the southeastern US. Mature pine savannahs with a minimal midstory and lush herbaceous groundcover represent high-quality habitat. This study examines the foraging-habitat patterns of Red-cockaded Woodpeckers in East Texas. We present a logistic regression model that best differentiates between foraged and non-foraged habitat. Increases in hardwood-midstory basal area have the greatest negative impact on the probability of Red-cockaded Woodpeckers selecting a habitat patch for foraging. Five additional variables negatively impact foraging probability: shrub height, diameter at breast height (DBH) of pine midstory, canopy closure, density of pine midstory, and density of hardwood midstory. Our model shows a high degree of accuracy as to the probability of habitat-patch selection for Red-cockaded Woodpeckers foraging in East Texas forests composed of different pine species.

The Daily QATM3 phantom from Sun Nuclear Corporation has been a popular daily quality assurance (QA) tool for many institutions. PTW has recently introduced the QUICKCHECKwebline phantom as an alternative. The goal of this study was to compare these two commercially available devices for daily quality assurance measurements of a linear accelerator and assess the overall performance of the new phantom.Two daily QA phantoms (PTW QUICKCHECKwebline and Sun Nuclear Corporation Daily QATM3) were measured over a 4-month period using a 20x20cm² field size and delivering 150 MU. Photon energies of 6 and 18 MV were measured on a daily basis, and electron energies of 6, 9, 12, 15, and 18 MeV were measured weekly on a 23EX Varian Linear Accelerator. Consistency of the dose output, beam flatness, in-plane and cross-plane symmetry, and beam quality were evaluated.The QUICKCHECKwebline and Daily QATM3 performed with maximum percent differences from baseline of -0.97% and 1.12% for output, 1.36% and 0.82% for flatness, 0.86% and -1.36% for in-plane symmetry, -1.41% and 1.00% for cross-plane symmetry, and -0.91% and 1.29% for beam quality respectively over all energies.Consistent and accurate measurements over a 4-month period, a user-friendly interface, and wireless features prove the QUICKCHECKwebline would be a suitable phantom for daily quality assurance use.

In single-isocenter stereotactic radiosurgery/radiotherapy (SRS/SRT) intracranial applications, multiple targets are being treated concurrently, often involving non-coplanar arcs, small photon beams and steep dose gradients. In search for more rigorous quality assurance protocols, this work presents and evaluates a novel methodology for patient-specific pre-treatment plan verification, utilizing 3D printing technology. In a patient's planning CT scan, the external contour and bone structures were segmented and 3D-printed using high-density bone-mimicking material. The resulting head phantom was filled with water while a film dosimetry insert was incorporated. Patient and phantom CT image series were fused and inspected for anatomical coherence. HUs and corresponding densities were compared in several anatomical regions within the head. Furthermore, the level of patient-to-phantom dosimetric equivalence was evaluated both computationally and experimentally. A single-isocenter multi-focal SRS treatment plan was prepared, while dose distributions were calculated on both CT image series, using identical calculation parameters. Phantom- and patient-derived dose distributions were compared in terms of isolines, DVHs, dose-volume metrics and 3D gamma index (GI) analysis. The phantom was treated as if the real patient and film measurements were compared against the patient-derived calculated dose distribution. Visual inspection of the fused CT images suggests excellent geometric similarity between phantom and patient, also confirmed using similarity indices. HUs and densities agreed within one standard deviation except for the skin (modeled as 'bone') and sinuses (water-filled). GI comparison between the calculated distributions resulted in passing rates better than 97% (1%/1 mm). DVHs and dose-volume metrics were also in satisfying agreement. In addition to serving as a feasibility proof-of-concept, experimental absolute film dosimetry verified the computational study results. GI passing rates were above 90%. Results of this work suggest that employing the presented methodology, patient-equivalent phantoms (except for the skin and sinuses areas) can be produced, enabling literally patient-specific pre-treatment plan verification in intracranial applications.

IMPACT: This work assesses clinical implementation of a surface guided imaging system to improve the accuracy radiation delivery for treatment of brain lesions using a patient CT derived head phantom. OBJECTIVES/GOALS: Advancements in radiotherapy design have made clinical demand for efficient and accurate methods to deliver stereotactic radiosurgery (SRS) for treatment of intracranial lesions. This study assesses the potential of using surface guided imaging for setup using a 3D patient specific head phantom. METHODS/STUDY POPULATION: A single isocenter, multiple metastases SRS plan was generated on a CT derived RTsafe Prime phantom made of tissue equivalent materials and a polymer gel insert. Five targets of varying diameters were treated with 8Gy of radiation using two different positioning techniques. The first gel insert was irradiated within the phantom according to internal alignment with standard orthogonal x-ray imaging while the second setup used surface guided imaging, based on external anatomy. 42 hours after irradiation, the phantom was scanned in a head coil using a 1.5T MRI. MR images were fused with the patient CT data and structure set to further evaluate calculated and measured dose distributions. RESULTS/ANTICIPATED RESULTS: Discrepancies in phantom setup according to standard orthogonal x-ray imaging compared to surface guided imaging demonstrated to be 94% (5%/2mm) and >87% (3%/2mm). Finally, 3 of 5 targets showed better 3D GI passing rates and less geometric offset for positioning with the surface guided imaging. DISCUSSION/SIGNIFICANCE OF FINDINGS: 3D spatial analysis of human like phantoms demonstrated that patient positioning according to external anatomy performed comparable to standard methods aligning to the internal anatomy, for a multiple met SRS treatment.

A DNA dosimeter (DNAd) was previously developed that uses double-strand breaks (DSB) to measure dose. This dosimeter has been tested to measure dose in scenarios where transient-charged particle equilibrium (TCPE) has been established. The probability of double strand break (PDSB(o)), which is the ratio of broken double-stranded DNA (dsDNA) to the initial unbroken dsDNA in the dosimeter, was used to quantify DSBs and related to dose. The goal of this work is to produce a new technique to process and analyze the DNAd and quantify DNA-DSBs. This technique included simultaneously processing multiple DNAds and also establishing a new form to the probability of double strand break (PDSB(n)), which was then used to test the DNAd in a non-TCPE condition by taking beam penumbra measurements. The technique utilized a 384-well plate, and the measurements were made at the edge of a 10 × 10 cm field and compared to film measurements. During these penumbra measurements, while observing the positional differences in the higher gradient region at 4.1 and 4.55 cm from the center of the radiation field, the distance to agreement of PDSB(o) to film were 0.38 cm and 0.26cm while the distance to agreement of PDSB(n) to film were 0.11 cm and 0.06 cm, respectively. Finally, the developed new separation technique reduced the time needed for the analysis of 25 samples from 200 minutes to 30 minutes.

Purpose: Temperature and pressure corrections are necessary to account for the varying mass of air in the sensitive volume of a vented ionization chamber (IC) when performing absolute dose measurements. Locations commonly used to measure the presumed IC air temperature may not accurately represent the chamber cavity air temperature, and phantoms undergoing temperature changes further compound the problem. Prior studies have characterized thermal equilibrium in separate phantoms for Farmer chambers alone. However, the purpose of this study was to characterize the cavity air temperature dependence on changes in the ambient temperature and phantom geometry configuration for a wider and more modern variety of chambers to determine if previously published wait times apply to these chambers as well. Methods: Thermal conduction properties were experimentally investigated by modifying a PTW 0.3 cm3 Semiflex IC with a thermocouple replacing the central electrode. Air cavity temperature versus time was recorded in three phantom geometries characteristic of common absolute dose measurements. The phantoms were (15 ± 1) °C before measurement with an IC at the treatment vault temperature of (21 ± 1) °C. Simulations were conducted to provide a theoretical basis for the measurements and to simulate temperature response of a PTW PinPoint® and Farmer chamber. The simulation methods were first validated by comparison with measured Semiflex chamber thermal response curves before extension to the other chambers. Results: Two thermal equilibria curves were recorded on different time scales. IC temperature initially dropped to the colder phantom temperature but subsequently increased as the phantom itself equilibrated with the warmer room temperature. In a large phantom of dimensions (25.5 × 25.5 × 23.4) cm3, 3 min was required before the IC temperature reached within 0.5 °C of its equilibrium within the phantom. Similarly, wait times of 2 min were needed for 7.5 and 2 cm slab phantoms. Conclusions: Recording of temperature in the phantom was deemed far more accurate than measurement in ambient air due to the air cavity thermally equilibrating with phantom temperature instead of the vented ambient air. Wait times of 3 and 2 min are needed for a cube and 7.5 cm slab phantom, respectively, to achieve 0.2% dosimetric accuracy (temperature accuracy of 0.5 °C). Chamber volume alone did not determine wait times, as a 0.3 cm3 IC required a longer wait time than a Farmer chamber, suggesting wall thickness as an important variable as well.

Our institution performs in vivo verification measurement for each of our total body irradiation (TBI) patients with optically stimulated luminescent dosimeters (OSLD). The lung block verification measurements were commonly higher than expected. The aim of this work is to understand this discrepancy and improve the accuracy of these lung block verification measurements. Initially, the thickness of the lung block was increased to provide adequate lung sparing. Further tests revealed the increase was due to electron contamination dose emanating from the lung block. The thickness of the bolus material covering the OSLD behind the lung block was increased to offset the electron contamination. In addition, the distance from the lung block to the dosimeter was evaluated for its effect on the OSLD reading and found to be clinically insignificant over the range of variability in our clinic. The results show that the improved TBI treatment technique provides for better accuracy of measured dose in vivo and consistency of patient setup. PACS number(s): 87.53.Bn, 87.53.Kn, 87.55.N‐, 87.55.Qr

The impact of roads on the flora and fauna of Neotropical rainforest is perhaps the single biggest driver of habitat modification and population declines in these ecosystems. We investigated the road-edge effect of a low-use dirt road on amphibian and reptile abundance, diversity, and composition within adjacent lowland Amazonian rainforest at San Jose de Payamino, Ecuador. The road has been closed to vehicle traffic since its construction in 2010. Thus, effects from vehicle mortality, vehicle-related pollution, and road noise were not confounding factors. Herpetofauna were surveyed using both visual encounter surveys and drift fences with pitfall and funnel traps at varying distances from the road. Structural and microclimate features of the forest were measured at each sampling distance. Several habitat variables were found to differ at intermediate and interior sampling distances from the road compared to forest edge conditions, suggesting the road-edge effect began to attenuate by the intermediate sam...

The purpose of this study is to report the dosimetric aspects of commissioning performed on an Elekta Versa HD linear accelerator (linac) with high‐dose‐rate flattening filter‐free (FFF) photon modes and electron modes. Acceptance and commissioning was performed on the Elekta Versa HD linac with five photon energies (6 MV, 10 MV, 18 MV, 6 MV FFF, 10 MV FFF), four electron energies (6 MeV, 9 MeV, 12 MeV, 15 MeV) and 160‐leaf (5 mm wide) multileaf collimators (MLCs). Mechanical and dosimetric data were measured and evaluated. The measurements include percent depth doses (PDDs), in‐plane and cross‐plane profiles, head scatter factor (Sc), relative photon output factors (Scp), universal wedge transmission factor, MLC transmission factors, and electron cone factors. Gantry, collimator, and couch isocentricity measurements were within 1 mm, 0.7 mm, and 0.7 mm diameter, respectively. The PDDs of 6 MV FFF and 10 MV FFF beams show deeper dmax and steeper falloff with depth than the corresponding flattened beams. While flatness values of 6 MV FFF and 10 MV FFF normalized profiles were expectedly higher than the corresponding flattened beams, the symmetry values were almost identical. The cross‐plane penumbra values were higher than the in‐plane penumbra values for all the energies. The MLC transmission values were 0.5%, 0.6%, and 0.6% for 6 MV, 10 MV, and 18 MV photon beams, respectively. The electron PDDs, profiles, and cone factors agree well with the literature. The outcome of radiation treatment is directly related to the accuracy in the dose modeled in the treatment planning system, which is based on the commissioned data. Commissioning data provided us a valuable insight into the dosimetric characteristics of the beam. This set of commissioning data can provide comparison data to others performing Versa HD commissioning, thereby improving patient safety. PACS number(s): 87.56.bd

The Elekta Versa HD incorporates a variety of upgrades to the line of Elekta linear accelerators, primarily including the Agility head and flattening filter‐free (FFF) photon beam delivery. The completely distinct dosimetric output of the head from its predecessors, combined with the FFF beams, requires a new investigation of modeling in treatment planning systems. A model was created in Pinnacle3 v9.8 with the commissioned beam data. A phantom consisting of several plastic water and Styrofoam slabs was scanned and imported into Pinnacle3, where beams of different field sizes, source‐to‐surface distances (SSDs), wedges, and gantry angles were devised. Beams included all of the available photon energies (6, 10, 18, 6 FFF, and 10 FFF MV), as well as the four electron energies commissioned for clinical use (6, 9, 12, and 15 MeV). The plans were verified at calculation points by measurement with a calibrated ionization chamber. Homogeneous and heterogeneous point‐dose measurements agreed within 2% relative to maximum dose for all photon and electron beams. AP photon open field measurements along the central axis at 100 cm SSD passed within 1%. In addition, IMRT testing was also performed with three standard plans (step and shoot IMRT, as well as a small‐ and large‐field VMAT plan). The IMRT plans were delivered on the Delta4 IMRT QA phantom, for which a gamma passing rate was >99.5% for all plans with a 3% dose deviation, 3 mm distance‐to‐agreement, and 10% dose threshold. The IMRT QA results for the first 23 patients yielded gamma passing rates of 97.4%±2.3%. Such testing ensures confidence in the ability of Pinnacle3 to model photon and electron beams with the Agility head. PACS numbers: 87.55.D, 87.56.bd