bluuebunny/crossref_metadata_2025_split huggingface dataset:
WE‐G‐BRD‐09: Novel MRI Compatible Electron Accelerator for MRI‐Linac Radiotherapy
Authors: Whelan B , Gierman S , Schmerge J , Holloway L , Keall P , Fahrig R 
Published: June 2015

Purpose:MRI guided radiotherapy is a rapidly growing field; however current linacs are not designed to operate in MRI fringe fields. As such, current MRI‐ Linac systems require magnetic shielding, impairing MR image quality and system flexibility. Here, we present a bespoke electron accelerator concept with robust operation in in‐line magnetic fields.Methods:For in‐line MRI‐Linac systems, electron gun performance is the major constraint on accelerator performance. To overcome this, we propose placing a cathode directly within the first accelerating cavity. Such a configuration is used extensively in high energy particle physics, but not previously for radiotherapy. Benchmarked computational modelling (CST, Darmstadt, Germany) was employed to design and assess a 5.5 cell side coupled accelerator with a temperature limited thermionic cathode in the first accelerating cell. This simulation was coupled to magnetic fields from a 1T MRI model to assess robustness in magnetic fields for Source to Isocenter Distance between 1 and 2 meters. Performance was compared to a conventional electron gun based system in the same magnetic field.Results:A temperature limited cathode (work function 1.8eV, temperature 1245K, emission constant 60A/K/cm2) will emit a mean current density of 24mA/mm2 (Richardson's Law). We modeled a circular cathode with radius 2mm and mean current 300mA. Capture efficiency of the device was 43%, resulting in target current of 130 mA. The electron beam had a FWHM of 0.2mm, and mean energy of 5.9MeV (interquartile spread of 0.1MeV). Such an electron beam is suitable for radiotherapy, comparing favourably to conventional systems. This model was robust to operation the MRI fringe field, with a maximum current loss of 6% compared to 85% for the conventional system.Conclusion:The bespoke electron accelerator is robust to operation in in‐line magnetic fields. This will enable MRI‐Linacs with no accelerator magnetic shielding, and minimise painstaking optimisation of the MRI fringe field.This work was supported by US (NIH) and Australian (NHMRC & Cancer Institute NSW) government research funding. In addition, I would like to thank cancer institute NSW and the Ingham Institute for scholarship support.
WE‐G‐BRA‐01: Patient Safety and Treatment Quality Improvement Through Incident Learning: Experience of a Non‐Academic Proton Therapy Center
Authors: Zheng Y , Johnson R , Zhao L , Ramirez E , Rana S , Singh H , Chacko M 
Published: June 2015

Purpose:Incident learning has been proven to improve patient safety and treatment quality in conventional radiation therapy. However, its application in proton therapy has not been reported yet to our knowledge. In this study, we report our experience in developing and implementation of an in‐house incident learning system.Methods:An incident learning system was developed based on published principles and tailored for our clinical practice and available resource about 18 months ago. The system includes four layers of error detection and report: 1) dosimetry peer review; 2) physicist plan quality assurance (QA); 3) treatment delivery issue on call and record; and 4) other incident report. The first two layers of QA and report were mandatory for each treatment plan through easy‐to‐use spreadsheets that are only accessible by the dosimetry and physicist departments. The treatment delivery issues were recorded case by case by the on call physicist. All other incidents were reported through an online incident report system, which can be anonymous. The incident report includes near misses on planning and delivery, process deviation, machine issues, work flow and documentation. Periodic incident reviews were performed.Results:In total, about 116 errors were reported through dosimetry review, 137 errors through plan QA, 83 treatment issues through physics on call record, and 30 through the online incident report. Only 8 incidents (2.2%) were considered to have a clinical impact to patients, and the rest of errors were either detected before reaching patients or had negligible dosimetric impact (<5% dose variance). Personnel training & process improvements were implemented upon periodic incident review.Conclusion:An incident learning system can be helpful in personnel training, error reduction, and patient safety and treatment quality improvement. The system needs to be catered for each clinic's practice and available resources. Incident and knowledge sharing among proton centers are encouraged.
WE‐G‐BRA‐03: Developing a Culture of Patient Safety Utilizing the National Radiation Oncology Incident Learning System (ROILS)
Authors: Hasson B , Workie D , Geraghty C 
Published: June 2015

Purpose:To transition from an in‐house incident reporting system to a ROILS standards system with the intent to develop a safety focused culture in the Department and enroll in ROILS.Methods:Since the AAPM Safety Summit (2010) several safety and reporting systems have been implemented within the Department. Specific checklists and SBAR reporting systems were introduced. However, the active learning component was lost due to reporting being viewed with distrust and possible retribution.To Facilitate introducing ROILS each leader in the Department received a copy of the ROILS participation guide. Four specific tasks were assigned to each leader: develop a reporting tree, begin the ROILS based system, facilitate adopting ROILS Terminology, and educate the staff on expectations of safety culture. Next, the ROILS questions were broken down into area specific questions (10–15) per departmental area. Excel spreadsheets were developed for each area and setup for error reporting entries. The Role of the Process Improvement Committee (PI) has been modified to review and make recommendations based on the ROILS entries.Results:The ROILS based Reporting has been in place for 4 months. To date 64 reports have been entered. Since the adoption of ROILS the reporting of incidents has increased from 2/month to 18/month on average. Three reports had a dosimetric effect on the patient (<5%) dose variance. The large majority of entries have been Characterized as Processes not followed or not sure how to Characterize, and Human Behavior.Conclusion:The majority of errors are typo's that create confusion. The introduction of the ROILS standards has provided a platform for making changes to policies that increase patient safety. The goal is to develop a culture that sees reporting at a national level as a safe and effective way to improve our safety, and to dynamically learn from other institutions reporting.
WE‐G‐BRA‐04: Common Errors and Deficiencies in Radiation Oncology Practice
Authors: Kry S , Dromgoole L , Alvarez P , Lowenstein J , Molineu A , Taylor P , Followill D 
Published: June 2015

Purpose:Dosimetric errors in radiotherapy dose delivery lead to suboptimal treatments and outcomes. This work reviews the frequency and severity of dosimetric and programmatic errors identified by on‐site audits performed by the IROC Houston QA center.Methods:IROC Houston on‐site audits evaluate absolute beam calibration, relative dosimetry data compared to the treatment planning system data, and processes such as machine QA. Audits conducted from 2000‐present were abstracted for recommendations, including type of recommendation and magnitude of error when applicable. Dosimetric recommendations corresponded to absolute dose errors >3% and relative dosimetry errors >2%. On‐site audits of 1020 accelerators at 409 institutions were reviewed.Results:A total of 1280 recommendations were made (average 3.1/institution). The most common recommendation was for inadequate QA procedures per TG‐40 and/or TG‐142 (82% of institutions) with the most commonly noted deficiency being x‐ray and electron off‐axis constancy versus gantry angle. Dosimetrically, the most common errors in relative dosimetry were in small‐field output factors (59% of institutions), wedge factors (33% of institutions), off‐axis factors (21% of institutions), and photon PDD (18% of institutions). Errors in calibration were also problematic: 20% of institutions had an error in electron beam calibration, 8% had an error in photon beam calibration, and 7% had an error in brachytherapy source calibration. Almost all types of data reviewed included errors up to 7% although 20 institutions had errors in excess of 10%, and 5 had errors in excess of 20%. The frequency of electron calibration errors decreased significantly with time, but all other errors show non‐significant changes.Conclusion:There are many common and often serious errors made during the establishment and maintenance of a radiotherapy program that can be identified through independent peer review. Physicists should be cautious, particularly in areas highlighted herein that show a tendency for errors.
WE‐G‐303‐00: Nanotechnology for Imaging and Therapy
Authors: Cho Sang Hyun 
Published: June 2015

Over the last decade, there has been a growing interest in applying nanotechnology to cancer detection, treatment, and treatment monitoring. Advances in nanotechnology have enabled the fabrication of nanoparticles from various materials with different shapes and sizes. Nanoparticles can be accumulated preferentially within tumors by either “passive targeting” through a phenomenon typically known as “enhanced permeability and retention” or “active targeting” in which nanoparticles are conjugated with antibodies or peptides directed against tumor and/or stromal markers. The tumor specificity of nanoparticles in conjunction with their unique physicochemical properties offers many novel strategies for cancer treatment and detection. For example, notable approaches in the radiation oncology setting include the use of gold nanoparticles for radiation response modulation of tumor or normal tissue and thermal ablation or hyperthermia treatment of tumors. Some of these approaches are currently being tested either on humans or on animals and, very likely, will become the clinical reality in the near future. Various computational and experimental techniques have also been applied to address unique research issues associated with nanoparticles and may become the standard tools for future investigations and clinical translations. Therefore, both clinicians and researchers may need to be properly educated about the basic principles as well as the promise of nanoparticle‐based applications with regard to the future of cancer diagnostics and therapeutics.This symposium will familiarize the audience with the potential applications of nanoparticles in oncologic imaging and therapy using specific illustrative examples. The audience will be properly oriented by these illustrative examples to the multiple avenues for collaborative research amongst interdisciplinary teams of physicists, clinicians, engineers, chemists, and biologists in industry and academia.Learning Objectives:

Understand the physical bases of gold nanoparticle applications for radiosensitization and x‐ray fluorescence imaging
Understand the parameters that define gold nanoparticle‐mediated radiosensitization in biological systems
Understand the potential of magnetic nanoparticle characterization of the microenvironment
Understand the various strategies for radiolabeling of nanoparticles and their applications
S.C. and S.K. acknowledge support from MD Anderson Cancer Center, NIH (R01CA155446 and P30CA16672) and DoD (W81XWH‐12‐1‐0198); J.W. acknowledges support from NIH (U54CA151662‐01); W.C. acknowledges support from the University of Wisconsin‐Madison, NIH (R01CA169365, P30CA014520, and T32CA009206), DoD (W81XWH‐11‐1‐0644 and W81XWH‐11‐1‐0648), and ACS (125246‐RSG‐13‐099‐01‐CCE).
WE‐G‐303‐02: Gold Nanoparticles as Radiosensitizers ‐ What Does It Take To Go From the Bench to the Bedside?
Authors: Krishnan S. 
Published: June 2015

Over the last decade, there has been a growing interest in applying nanotechnology to cancer detection, treatment, and treatment monitoring. Advances in nanotechnology have enabled the fabrication of nanoparticles from various materials with different shapes and sizes. Nanoparticles can be accumulated preferentially within tumors by either “passive targeting” through a phenomenon typically known as “enhanced permeability and retention” or “active targeting” in which nanoparticles are conjugated with antibodies or peptides directed against tumor and/or stromal markers. The tumor specificity of nanoparticles in conjunction with their unique physicochemical properties offers many novel strategies for cancer treatment and detection. For example, notable approaches in the radiation oncology setting include the use of gold nanoparticles for radiation response modulation of tumor or normal tissue and thermal ablation or hyperthermia treatment of tumors. Some of these approaches are currently being tested either on humans or on animals and, very likely, will become the clinical reality in the near future. Various computational and experimental techniques have also been applied to address unique research issues associated with nanoparticles and may become the standard tools for future investigations and clinical translations. Therefore, both clinicians and researchers may need to be properly educated about the basic principles as well as the promise of nanoparticle‐based applications with regard to the future of cancer diagnostics and therapeutics.This symposium will familiarize the audience with the potential applications of nanoparticles in oncologic imaging and therapy using specific illustrative examples. The audience will be properly oriented by these illustrative examples to the multiple avenues for collaborative research amongst interdisciplinary teams of physicists, clinicians, engineers, chemists, and biologists in industry and academia.Learning Objectives:

Understand the physical bases of gold nanoparticle applications for radiosensitization and x‐ray fluorescence imaging
Understand the parameters that define gold nanoparticle‐mediated radiosensitization in biological systems
Understand the potential of magnetic nanoparticle characterization of the microenvironment
Understand the various strategies for radiolabeling of nanoparticles and their applications
S.C. and S.K. acknowledge support from MD Anderson Cancer Center, NIH (R01CA155446 and P30CA16672) and DoD (W81XWH‐12‐1‐0198); J.W. acknowledges support from NIH (U54CA151662‐01); W.C. acknowledges support from the University of Wisconsin‐Madison, NIH (R01CA169365, P30CA014520, and T32CA009206), DoD (W81XWH‐11‐1‐0644 and W81XWH‐11‐1‐0648), and ACS (125246‐RSG‐13‐099‐01‐CCE).
WE‐G‐303‐04: Intrinsically Radiolabeled Nanoparticles: An Emerging Paradigm
Authors: Cai W. 
Published: June 2015

Over the last decade, there has been a growing interest in applying nanotechnology to cancer detection, treatment, and treatment monitoring. Advances in nanotechnology have enabled the fabrication of nanoparticles from various materials with different shapes and sizes. Nanoparticles can be accumulated preferentially within tumors by either “passive targeting” through a phenomenon typically known as “enhanced permeability and retention” or “active targeting” in which nanoparticles are conjugated with antibodies or peptides directed against tumor and/or stromal markers. The tumor specificity of nanoparticles in conjunction with their unique physicochemical properties offers many novel strategies for cancer treatment and detection. For example, notable approaches in the radiation oncology setting include the use of gold nanoparticles for radiation response modulation of tumor or normal tissue and thermal ablation or hyperthermia treatment of tumors. Some of these approaches are currently being tested either on humans or on animals and, very likely, will become the clinical reality in the near future. Various computational and experimental techniques have also been applied to address unique research issues associated with nanoparticles and may become the standard tools for future investigations and clinical translations. Therefore, both clinicians and researchers may need to be properly educated about the basic principles as well as the promise of nanoparticle‐based applications with regard to the future of cancer diagnostics and therapeutics.This symposium will familiarize the audience with the potential applications of nanoparticles in oncologic imaging and therapy using specific illustrative examples. The audience will be properly oriented by these illustrative examples to the multiple avenues for collaborative research amongst interdisciplinary teams of physicists, clinicians, engineers, chemists, and biologists in industry and academia.Learning Objectives:

Understand the physical bases of gold nanoparticle applications for radiosensitization and x‐ray fluorescence imaging
Understand the parameters that define gold nanoparticle‐mediated radiosensitization in biological systems
Understand the potential of magnetic nanoparticle characterization of the microenvironment
Understand the various strategies for radiolabeling of nanoparticles and their applications
S.C. and S.K. acknowledge support from MD Anderson Cancer Center, NIH (R01CA155446 and P30CA16672) and DoD (W81XWH‐12‐1‐0198); J.W. acknowledges support from NIH (U54CA151662‐01); W.C. acknowledges support from the University of Wisconsin‐Madison, NIH (R01CA169365, P30CA014520, and T32CA009206), DoD (W81XWH‐11‐1‐0644 and W81XWH‐11‐1‐0648), and ACS (125246‐RSG‐13‐099‐01‐CCE).
TH‐AB‐BRD‐03: Radiation Dosimetry for Proton Therapy
Authors: Sahoo N. 
Published: June 2015

The goal of this session is to introduce the audience to the physics, dosimetry, treatment planning techniques, and quality assurances (QA) procedures used in proton therapy. The course material covers the physics of proton interaction with matter and physical characteristics of clinical proton beams. It will provide information on proton delivery systems and beam delivery techniques for double scattering (DS), uniform scanning (US), and pencil beam scanning (PBS). The session covers the treatment planning strategies used in DS, US, and PBS for various anatomical sites, methods to address uncertainties in proton therapy and uncertainty mitigation to generate robust treatment plans. Challenges involved in the motion management in proton therapy will also be discussed. It will also include the methodology for proton beam dosimetry for clinical commissioning, beam calibration, and quality assurance checks.Learning Objectives:

Gain knowledge on physics, dosimetry, and treatment planning for proton therapy including intensity modulated proton therapy.
Be acquainted with the procedures involved in machine and patient treatment field specific QA.
Understand the uncertainties associated with proton therapy and currently used strategies for their mitigation in treatment planning.
Xanthomonas campestris pv. vesicatoria Secretes Proteases and Xylanases via the Xps Type II Secretion System and Outer Membrane Vesicles
Authors: Solé Magali , Scheibner Felix , Hoffmeister Anne-Katrin , Hartmann Nadine , Hause Gerd , Rother Annekatrin , Jordan Michael , Lautier Martine , Arlat Matthieu , Büttner Daniela 
Published: June 2015

ABSTRACT

Many plant-pathogenic bacteria utilize type II secretion (T2S) systems to secrete degradative enzymes into the extracellular milieu. T2S substrates presumably mediate the degradation of plant cell wall components during the host-pathogen interaction and thus promote bacterial virulence. Previously, the Xps-T2S system from
Xanthomonas campestris
pv. vesicatoria was shown to contribute to extracellular protease activity and the secretion of a virulence-associated xylanase. The identities and functions of additional T2S substrates from
X. campestris
pv. vesicatoria, however, are still unknown. In the present study, the analysis of 25 candidate proteins from
X. campestris
pv. vesicatoria led to the identification of two type II secreted predicted xylanases, a putative protease and a lipase which was previously identified as a virulence factor of
X. campestris
pv. vesicatoria. Studies with mutant strains revealed that the identified xylanases and the protease contribute to virulence and
in planta
growth of
X. campestris
pv. vesicatoria. When analyzed in the related pathogen
X. campestris
pv. campestris, several T2S substrates from
X. campestris
pv. vesicatoria were secreted independently of the T2S systems, presumably because of differences in the T2S substrate specificities of the two pathogens. Furthermore, in
X. campestris
pv. vesicatoria T2S mutants, secretion of T2S substrates was not completely absent, suggesting the contribution of additional transport systems to protein secretion. In line with this hypothesis, T2S substrates were detected in outer membrane vesicles, which were frequently observed for
X. campestris
pv. vesicatoria. We, therefore, propose that extracellular virulence-associated enzymes from
X. campestris
pv. vesicatoria are targeted to the Xps-T2S system and to outer membrane vesicles.

IMPORTANCE
The virulence of plant-pathogenic bacteria often depends on TS2 systems, which secrete degradative enzymes into the extracellular milieu. T2S substrates are being studied in several plant-pathogenic bacteria, including
Xanthomonas campestris
pv. vesicatoria, which causes bacterial spot disease in tomato and pepper. Here, we show that the T2S system from
X. campestris
pv. vesicatoria secretes virulence-associated xylanases, a predicted protease, and a lipase. Secretion assays with the related pathogen
X. campestris
pv. campestris revealed important differences in the T2S substrate specificities of the two pathogens. Furthermore, electron microscopy showed that T2S substrates from
X. campestris
pv. vesicatoria are targeted to outer membrane vesicles (OMVs). Our results, therefore, suggest that OMVs provide an alternative transport route for type II secreted extracellular enzymes.
The IS
200
/IS
605
Family and “Peel and Paste” Single-strand Transposition Mechanism
Authors: He S. , Corneloup A. , Guynet C. , Lavatine L. , Caumont-Sarcos A. , Siguier P. , Marty B. , Dyda F. , Chandler M. , Ton Hoang B. 
Published: June 2015

ABSTRACT

This chapter presents an analysis of the organization and distribution of the IS
200
/IS
605
family of insertion sequences (IS). Members of this family are widespread in both bacteria and archaea. They are unusual because they use obligatory single-strand DNA intermediates, which distinguishes them from classical IS. We summarize studies of the experimental model systems IS
608
(from
Helicobacter pylori
) and IS
Dra2
(from
Deinococcus radiodurans
) and present biochemical, genetic, and structural data that describe their transposition pathway and the way in which their transposase (an HuH rather than a DDE enzyme) catalyzes this process. The transposition of IS
200
/IS
605
family members can be described as a “Peel-and-Paste” mechanism. We also address the probable domestication of IS
200
/IS
605
family transposases as enzymes involved in multiplication of repeated extragenic palindromes and as potential homing endonucleases in intron–IS chimeras.