bluuebunny/crossref_metadata_2025_split huggingface dataset:
Road traffic injuries in northern Laos: trends and risk factors of an underreported public health problem
Authors: Slesak Günther , Inthalath Saythong , Wilder‐Smith Annelies , Barennes Hubert 
Published: June 2015

AbstractObjectivesRoad traffic injuries (RTI) have become a leading cause for admissions at Luang Namtha Provincial Hospital (LNPH) in rapidly developing northern Laos. Objectives were to investigate trends, risk factors and better estimates of RTI.MethodsRepeated annual surveys were conducted with structured questionnaires among all RTI patients at LNPH from 2007 to 2011. Hospital and police data were combined by capture–recapture method.ResultsThe majority of 1074 patients were young [median 22 years (1–88)], male (68%), motorcyclists (76%), drove without licence (85%) and without insurance (95%). Most accidents occurred during evenings and Lao New Year. Serious motorbike injuries were associated with young age (1–15 years), male sex (OR 2.2, 95% CI 1.1–4.6) and drivers (OR 2.1, 95% CI 1.1–4.3); more serious head injuries with alcohol consumption (OR 2.5, 95% CI 1.7–3.7), male sex (OR 2.3, 95% CI 1.4–3.7) and no helmet use (OR 2.0, 95% CI 1.2–3.4). No helmet use was associated with young age, time period, pillion passengers (OR 2.7, 95% CI 1.6–4.7), alcohol (OR 1.9, 95% CI 1.2–2.8) and no driver license (OR 2.0; 95% CI 1.1–3.4). Main reasons not to wear helmets were not possessing one, and being pillion passenger. Capture–recapture analysis showed four times higher RTI estimates than officially reported. Mortality rate was 11.6/100.000 population (95% CI 5.1–18.1/100.000).ConclusionsRTI were substantially underestimated. Combining hospital with police data can provide better estimates in resource‐limited settings. Preventive programmes and law enforcement have to target male drivers, alcohol, licensing and helmet use, especially among children and pillion passengers. Increased efforts are needed during evening time and special festivals.
The deubiquitinating enzyme AMSH1 is required for rhizobial infection and nodule organogenesis in Lotus japonicus
Authors: Małolepszy Anna , Urbański Dorian Fabian , James Euan K. , Sandal Niels , Isono Erika , Stougaard Jens , Andersen Stig Uggerhøj 
Published: June 2015

SummaryLegume–rhizobium symbiosis contributes large quantities of fixed nitrogen to both agricultural and natural ecosystems. This global impact and the selective interaction between rhizobia and legumes culminating in development of functional root nodules have prompted detailed studies of the underlying mechanisms. We performed a screen for aberrant nodulation phenotypes using the Lotus japonicus LORE1 insertion mutant collection. Here, we describe the identification of amsh1 mutants that only develop small nodule primordia and display stunted shoot growth, and show that the aberrant nodulation phenotype caused by LORE1 insertions in the Amsh1 gene may be separated from the shoot phenotype. In amsh1 mutants, rhizobia initially became entrapped in infection threads with thickened cells walls. Some rhizobia were released into plant cells much later than observed for the wild‐type; however, no typical symbiosome structures were formed. Furthermore, cytokinin treatment only very weakly induced nodule organogenesis in amsh1 mutants, suggesting that AMSH1 function is required downstream of cytokinin signaling. Biochemical analysis showed that AMSH1 is an active deubiquitinating enzyme, and that AMSH1 specifically cleaves K63‐linked ubiquitin chains. Post‐translational ubiquitination and deubiquitination processes involving the AMSH1 deubiquitinating enzyme are thus involved in both infection and organogenesis in Lotus japonicus.
OsARID3, an AT‐rich Interaction Domain‐containing protein, is required for shoot meristem development in rice
Authors: Xu Yan , Zong Wei , Hou Xin , Yao Jialing , Liu Hongbo , Li Xianghua , Zhao Yunde , Xiong Lizhong 
Published: June 2015

SummaryThe shoot apical meristem (SAM) produces all of the plant's aerial organs. The SAM is established either during embryogenesis or experimentally in in vitro tissue culture. Although several factors including the Class I KNOTTED1‐LIKE HOMEOBOX (KNOXI) proteins, auxin, and cytokinin are known to play essential roles in SAM development, the underlying mechanisms of SAM formation and maintenance are still largely not understood. Herein we demonstrate that OsARID3, a member of the rice (Oryza sativa) AT‐rich Interaction Domain (ARID) family, is required for SAM development. Disruption of OsARID3 leads to a defective SAM, early seedling lethality, and impaired capacity of in vitro shoot regeneration. We show that the expression levels of several KNOXI genes and the biosynthetic genes for auxin and cytokinin are significantly altered in the Osarid3 mutant calli. Moreover, we determine that auxin concentrations are increased, whereas cytokinin levels are decreased, in Osarid3 calli. Furthermore, chromatin immunoprecipitation results demonstrate that OsARID3 binds directly to the KNOXI gene OSH71, the auxin biosynthetic genes OsYUC1 and OsYUC6, and the cytokinin biosynthetic genes OsIPT2 and OsIPT7. We also show through electrophoretic mobility shift assays that OsARID3 specifically binds to the AT‐rich DNA sequences of the identified target genes. We conclude that OsARID3 is an AT‐rich specific DNA‐binding protein and that it plays a major role in SAM development in rice.
Optimizing Eating Performance for Older Adults With Dementia Living in Long‐term Care: A Systematic Review
Authors: Liu Wen , Galik Elizabeth , Boltz Marie , Nahm Eun‐Shim , Resnick Barbara 
Published: June 2015

ABSTRACTBackgroundReview of research to date has been focusing on maintaining weight and nutrition with little attention on optimizing eating performance.ObjectiveTo evaluate the effectiveness of interventions on eating performance for older adults with dementia in long‐term care (LTC).MethodsA systematic review was performed. Five databases including Pubmed, Medline (OVID), EBM Reviews (OVID), PsychINFO (OVID), and CINAHL (EBSCOHost) were searched between January 1980 and June 2014. Keywords included dementia, Alzheimer, feed(ing), eat(ing), mealtime(s), oral intake, autonomy, and intervention. Intervention studies that optimize eating performance and evaluate change of self‐feeding or eating performance among older adults (≥65 years) with dementia in LTC were eligible. Studies were screened by title and abstract, and full texts were reviewed for eligibility. Eligible studies were classified by intervention type. Study quality was accessed using the Quality Assessment Tool for Quantitative Studies, and level of evidence using the 2011 Oxford Centre for Evidence‐Based Medicine (OCEBM) Levels of Evidence.ResultsEleven intervention studies (five randomized controlled trials [RCTs]) were identified, and classified into four types: training program, mealtime assistance, environmental modification, and multicomponent intervention. The quality of the 11 studies was generally moderate (four studies were rated as strong, four moderate, and three weak in quality), with the main threats as weak designs, lack of blinding and control for confounders, and inadequate psychometric evidence for measures. Training programs targeting older adults (Montessori methods and spaced retrieval) demonstrated good evidence in decreasing feeding difficulty. Mealtime assistance offered by nursing staff (e.g., verbal prompts and cues, positive reinforcement, appropriate praise and encouragement) also showed effectiveness in improving eating performance.Linking evidence to actionThis review provided preliminary support for using training and mealtime assistance to optimize eating performance for older adults with dementia in LTC. Future effectiveness studies may focus on training nursing caregivers as interventionists, lengthening intervention duration, and including residents with varying levels of cognitive impairment in diverse cultures. The effectiveness of training combined with mealtime assistance may also be tested to achieve better resident outcomes in eating performance.
Control Rod Withdrawal Analysis of the Supercritical Water Reactor-Fuel Qualification Test Facility in the LVR-15 Research Reactor
Authors: Maráczy Csaba , Hegyi György , Trosztel István , Temesvári Emese 
Published: June 2015

The aim of the supercritical water reactor-fuel qualification test (SCWR-FQT) Euratom-China collaborative project is to design an experimental facility for qualification of fuel for the supercritical water-cooled reactor. The facility is intended to be operated in the LVR-15 research reactor in the Czech Republic. The pressure tube of the FQT facility encloses four fuel rods that will operate in similar conditions to the evaporator of the HPLWR reactor. This article deals with the three-dimensional (3D) coupled neutronic-thermohydraulic steady-state and transient analysis of LVR-15 with the fueled loop. Conservatively calculated enveloping parameters (e.g., reactivity coefficients) were determined for the safety analysis. The control rod withdrawal analysis of the FQT facility with and without reactor SCRAM was carried out with the KIKO3D-ATHLET-coupled dynamic code.
Experimental demonstration of passive acoustic imaging in the human skull cavity using CT‐based aberration corrections
Authors: Jones Ryan M. , O'Reilly Meaghan A. , Hynynen Kullervo 
Published: June 2015

Purpose:Experimentally verify a previously described technique for performing passive acoustic imaging through an intact human skull using noninvasive, computed tomography (CT)‐based aberration corrections Jones et al. [Phys. Med. Biol. 58, 4981–5005 (2013)].Methods:A sparse hemispherical receiver array (30 cm diameter) consisting of 128 piezoceramic discs (2.5 mm diameter, 612 kHz center frequency) was used to passively listen through ex vivo human skullcaps (n = 4) to acoustic emissions from a narrow‐band fixed source (1 mm diameter, 516 kHz center frequency) and from ultrasound‐stimulated (5 cycle bursts, 1 Hz pulse repetition frequency, estimated in situ peak negative pressure 0.11–0.33 MPa, 306 kHz driving frequency) Definity™ microbubbles flowing through a thin‐walled tube phantom. Initial in vivo feasibility testing of the method was performed. The performance of the method was assessed through comparisons to images generated without skull corrections, with invasive source‐based corrections, and with water‐path control images.Results:For source locations at least 25 mm from the inner skull surface, the modified reconstruction algorithm successfully restored a single focus within the skull cavity at a location within 1.25 mm from the true position of the narrow‐band source. The results obtained from imaging single bubbles are in good agreement with numerical simulations of point source emitters and the authors’ previous experimental measurements using source‐based skull corrections O'Reilly et al. [IEEE Trans. Biomed. Eng. 61, 1285–1294 (2014)]. In a rat model, microbubble activity was mapped through an intact human skull at pressure levels below and above the threshold for focused ultrasound‐induced blood–brain barrier opening. During bursts that led to coherent bubble activity, the location of maximum intensity in images generated with CT‐based skull corrections was found to deviate by less than 1 mm, on average, from the position obtained using source‐based corrections.Conclusions:Taken together, these results demonstrate the feasibility of using the method to guide bubble‐mediated ultrasound therapies in the brain. The technique may also have application in ultrasound‐based cerebral angiography.
SU‐B‐213‐07: Panel Discussion
Authors: Starkschall G. 
Published: June 2015

The North American medical physics community validates the education received by medical physicists and the clinical qualifications for medical physicists through accreditation of educational programs and certification of medical physicists. Medical physics educational programs (graduate education and residency education) are accredited by the Commission on Accreditation of Medical Physics Education Programs (CAMPEP), whereas medical physicists are certified by several organizations, the most familiar of which is the American Board of Radiology (ABR). In order for an educational program to become accredited or a medical physicist to become certified, the applicant must meet certain specified standards set by the appropriate organization.In this Symposium, representatives from both CAMPEP and the ABR will describe the process by which standards are established as well as the process by which qualifications of candidates for accreditation or certification are shown to be compliant with these standards.The Symposium will conclude with a panel discussion.Learning Objectives:

Recognize the difference between accreditation of an educational program and certification of an individual
Identify the two organizations primarily responsible for these tasks
Describe the development of educational standards
Describe the process by which examination questions are developed
GS is Executive Secretary of CAMPEP.
SU‐C‐213‐02: Characterizing 3D Printing in the Fabrication of Variable Density Phantoms
Authors: Madamesila J , McGeachy P , Villarreal‐Barajas J , Khan R 
Published: June 2015

Purpose:In this work, we present characterization, process flow, quality control and application of 3D fabricated low density phantoms for radiotherapy quality assurance.Methods:A Rostock delta 3D printer using polystyrene filament of diameter 1.75 mm was used to print geometric volumes of 2×2×1 cm3 of varying densities. The variable densities of 0.1 to 0.75 g/cm 3 were created by modulating the infill. A computed tomography (CT) scan was performed to establish an infill‐density calibration curve as well as characterize the quality of the print such as uniformity and the infill pattern. The time required to print these volumes was also recorded. Using the calibration, two low density cones (0.19, 0.52 g/cm3) were printed and benchmarked against commercially available phantoms. The dosimetric validation of the low density scaling of Anisotropic Analytical Algorithm (AAA) was performed by using a 0.5 g/cm3 slab of 10×10×2.4 cm3 with EBT3 GafChromic film. The gamma analysis at 3%/3mm criteria were compared for the measured and computed dose planes.Results:Analysis of the volume of air pockets in the infill resulted in a reasonable uniformity for densities 0.4 to 0.75 g/cm3. Printed phantoms with densities below 0.4 g/cm3 exhibited a higher ratio of air to polystyrene resulting in large non‐uniformity. Compared to the commercial inserts, good agreement was observed only for the printed 0.52 g/cm3 cone. Dosimetric comparison for a printed low density volume placed in‐between layers of solid water resulted in >95% gamma agreement between AAA calculated dose planes and measured EBT3 films for a 6MV 5×5 cm2 clinical beam. The comparison showed disagreement in the penumbra region.Conclusion:In conclusion, 3D printing technology opens the door to desktop fabrication of variable density phantoms at economical prices in an efficient manner for the quality assurance needs of a small clinic.
SU‐C‐213‐05: Evaluation of a Composite Copper‐Plastic Material for a 3D Printed Radiation Therapy Bolus
Authors: Vitzthum L , Ehler E , Sterling D , Reynolds T , Higgins P , Dusenbery K 
Published: June 2015

Purpose:To evaluate a novel 3D printed bolus fabricated from a copper‐plastic composite as a thin flexible, custom fitting device that can replicate doses achieved with conventional bolus techniques.Methods:Two models of bolus were created on a 3D printer using a composite copper‐PLA/PHA. Firstly, boluses were constructed at thicknesses of 0.4, 0.6 and 0.8 mm. Relative dose measurements were performed under the bolus with an Attix Chamber as well as with radiochromic film. Results were compared to superficial Attix Chamber measurements in a water equivalent material to determine the dosimetric water equivalence of the copper‐PLA/PHA plastic. Secondly, CT images of a RANDO phantom were used to create a custom fitting bolus across the anterolateral scalp. Surface dose with the bolus placed on the RANDO phantom was measured with radiochromic film at tangential angles with 6, 10, 10 flattening filter free (FFF) and 18 MV photon beams.Results:Mean surface doses for 6, 10, 10FFF and 18 MV were measured as a percent of Dmax for the flat bolus devices of each thickness. The 0.4 mm thickness bolus was determined to be near equivalent to 2.5 mm depth in water for all four energies. Surface doses ranged from 59–63% without bolus and 85–90% with the custom 0.4 mm copper‐plastic bolus relative to the prescribed dose for an oblique tangential beam arrangement on the RANDO phantom.Conclusion:Sub‐millimeter thickness, 3D printed composite copper‐PLA/PHA bolus can provide a build‐up effect equivalent to conventional bolus. At this thickness, the 3D printed bolus allows a level of flexure that may provide more patient comfort than current 3D printing materials used in bolus fabrication while still retaining the CT based custom patient shape.Funding provided by an intra‐department grant of the University of Minnesota Department of Radiation Oncology
SU‐C‐304‐01: Investigation of Various Detector Response Functions and Their Geometry Dependence in a Novel Method to Address Ion Chamber Volume Averaging Effect
Authors: Barraclough B , Li J , Lebron S , Fan Qiyong , Liu C , Yan G 
Published: June 2015

Purpose:A novel convolution‐based approach has been proposed to address ion chamber (IC) volume averaging effect (VAE) for the commissioning of commercial treatment planning systems (TPS). We investigate the use of various convolution kernels and its impact on the accuracy of beam models.Methods:Our approach simulates the VAE by iteratively convolving the calculated beam profiles with a detector response function (DRF) while optimizing the beam model. At convergence, the convolved profiles match the measured profiles, indicating the calculated profiles match the “true” beam profiles. To validate the approach, beam profiles of an Elekta LINAC were repeatedly collected with ICs of various volumes (CC04, CC13 and SNC 125) to obtain clinically acceptable beam models. The TPS‐calculated profiles were convolved externally with the DRF of respective IC. The beam model parameters were reoptimized using Nelder‐Mead method by forcing the convolved profiles to match the measured profiles. We evaluated three types of DRFs (Gaussian, Lorentzian, and parabolic) and the impact of kernel dependence on field geometry (depth and field size). The profiles calculated with beam models were compared with SNC EDGE diode‐measured profiles.Results:The method was successfully implemented with Pinnacle Scripting and Matlab. The reoptimization converged in ∼10 minutes. For all tested ICs and DRFs, penumbra widths of the TPS‐calculated profiles and diode‐measured profiles were within 1.0 mm. Gaussian function had the best performance with mean penumbra width difference within 0.5 mm. The use of geometry dependent DRFs showed marginal improvement, reducing the penumbra width differences to less than 0.3 mm. Significant increase in IMRT QA passing rates was achieved with the optimized beam model.Conclusion:The proposed approach significantly improved the accuracy of the TPS beam model. Gaussian functions as the convolution kernel performed consistently better than Lorentzian and parabolic functions. Further improvement of using geometry‐dependent kernels was marginal.
SU‐C‐304‐03: Experimental Investigation On the Accuracy of Plastic Scintillation Dosimeters in Small Fields
Authors: Papaconstadopoulos P , Archambault L , Seuntjens J 
Published: June 2015

Purpose:To investigate the accuracy of the Exradin W1 (SI) and of an “in‐house” plastic scintillation dosimeter (CHUQ PSD) in small radiation fields.Methods:Output factor (OF) measurements with the W1 and CHUQ PSD were performed for field sizes of 0.5 × 0.5, 1 × 1 and 2 × 2 cm2. Both detectors were placed parallel to the central axis (CAX) in water. The spectrum discrimination calibration method was performed in each set‐up to account for the Cerenkov (CRV) signal created in the fiber. The OFs were compared to the expected field factors in water derived using i) Monte Carlo (MC) simulations of an accurate accelerator model and ii) microLion (PTW) and D1V diode (SI) OFs. MC‐derived correction factors were applied to both the microLion and D1V OFs. For the CHUQ PSD the calibration was repeated in water (// CAX), solid water (perpendicular to CAX) and under a shielded configuration. The signal was collected using a spectrometer (wavelength range = 185–1100 nm). Spectral analysis was performed to evaluate potential changes of the spectral distributions under the various calibration set‐up configurations.Results:The W1 OFs presented an over‐response for the 0.5 × 0.5 cm2 in the range of 3 – 4.1% relative to the expected field factor. The CHUQ PSD presented an under‐response in the range of 1.5 – 2.7%, without accounting for volume averaging. The CRV spectra under the various calibration procedures appeared similar to each other and only minor changes were observed to the respective OFs.Conclusion:The W1 and CHUQ PSD can be used in small fields down to a 1 × 1 cm2 field size. Discrepancies were encountered between the two detectors for the smallest field size of 0.5 × 0.5 cm2 with the CHUQ PSD exhibiting a closer agreement to the expected field factor.Funding sources: 1) Alexander S. Onassis Public Benefit Foundation in Greece and 2) CREATE Medical Physics Research Training Network grant of the Natural Sciences and Engineering Research Council, Grant number: 432290, RGPIN‐2014‐06475
SU‐C‐304‐07: Are Small Field Detector Correction Factors Strongly Dependent On Machine‐Specific Characteristics?
Authors: Mathew D , Tanny S , Parsai E , Sperling N 
Published: June 2015

Purpose:The current small field dosimetry formalism utilizes quality correction factors to compensate for the difference in detector response relative to dose deposited in water. The correction factors are defined on a machine‐specific basis for each beam quality and detector combination. Some research has suggested that the correction factors may only be weakly dependent on machine‐to‐machine variations, allowing for determinations of class‐specific correction factors for various accelerator models. This research examines the differences in small field correction factors for three detectors across two Varian Truebeam accelerators to determine the correction factor dependence on machine‐specific characteristics.Methods:Output factors were measured on two Varian Truebeam accelerators for equivalently tuned 6 MV and 6 FFF beams. Measurements were obtained using a commercial plastic scintillation detector (PSD), two ion chambers, and a diode detector. Measurements were made at a depth of 10 cm with an SSD of 100 cm for jaw‐defined field sizes ranging from 3×3 cm2 to 0.6×0.6 cm2, normalized to values at 5×5cm2. Correction factors for each field on each machine were calculated as the ratio of the detector response to the PSD response. Percent change of correction factors for the chambers are presented relative to the primary machine.Results:The Exradin A26 demonstrates a difference of 9% for 6×6mm2 fields in both the 6FFF and 6MV beams. The A16 chamber demonstrates a 5%, and 3% difference in 6FFF and 6MV fields at the same field size respectively. The Edge diode exhibits less than 1.5% difference across both evaluated energies. Field sizes larger than 1.4×1.4cm2 demonstrated less than 1% difference for all detectors.Conclusion:Preliminary results suggest that class‐specific correction may not be appropriate for micro‐ionization chamber. For diode systems, the correction factor was substantially similar and may be useful for class‐specific reference conditions.