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"Kirk, Julie"
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The design and Performance of the Atlas Inner Detector Trigger in High Pileup Collisions at 13 Tev at the Large Hadron Collider
2019
The design and performance of the ATLAS Inner Detector (ID) trigger algorithms running online on the High Level Trigger (HLT) processor farm for 13 TeV LHC collision data with high pileup are discussed. The HLT ID tracking is a vital component in all physics signatures in the ATLAS trigger for the precise selection of the rare or interesting events necessary for physics analysis without overwhelming the offline data storage in terms of both size and rate. To cope with the high interaction rates expected in the 13 TeV LHC collisions, the ID trigger was redesigned during the 2013-15 long shutdown. The performance of the ID trigger in Run 2 data from 13 TeV LHC collisions has been excellent and exceeded expectations, even at the very high interaction multiplicities observed at the end of data-taking in 2017. The detailed efficiencies and resolutions of the ID trigger in a wide range of physics signatures are presented for the Run 2 data. The superb performance of the ID trigger algorithms in these extreme pileup conditions demonstrates how the ID tracking continues to lie at the heart of the trigger performance to enable the ATLAS physics program, and will continue to do so in the future.
Journal Article
Evaluation of radiotherapy planning approaches for head and neck patients with tumors close to the skin surface
2024
Purpose In radiotherapy of the head and neck (H&N) it is common for the clinical target volume (CTV) to extend to the patient's skin. Adding a margin for set‐up uncertainty and delivery creates a planning target volume (PTV) that extends beyond the patient surface. This can result in excessive fluence being delivered to the build‐up region and therefore the skin. This study evaluates four different planning methods used when inverse‐planning H&N radiotherapy treatments with CTV extending to the skin. The aim of the study was to determine which planning method gives superior plan quality. Method Ten H&N cancer patients with a CTV contoured to the skin were inverse‐planned using four planning methods. The planning methods compared were: cropping the optimization PTV back from the skin surface by 5.0, 3.0, and 0.0 mm and a virtual bolus method. For each planning method, the increased fluence at the skin surface was analyzed. The CTV coverage and skin doses were compared. Plan robustness was evaluated by applying an isocenter shift of ±3.0 mm in the major axes. Results The planning method cropping the PTV 0.0 mm from the skin surface results in an increased fluence in the build‐up region. The average volume of CTV receiving 98% of the prescription dose was 89.6% ± 3.4%, 91.6% ± 2.4%, and 93.5% ± 1.7% when cropped 5.0, 3.0, and 0.0 mm, respectively, and 93.4% ± 2.1% for the virtual bolus method. Introducing plan uncertainty affects CTV coverage the most when cropping 5.0 mm. When plan uncertainties are considered the methods of cropping 5.0, 3.0 mm, and the virtual bolus method have the same average skin dose within ±0.3%. Conclusion This study shows that a virtual bolus planning method results in no increased fluence at the patient's surface, improves CTV coverage, and is the most robust to changes in setup and patient anatomy.
Journal Article
Hypofractionated breast radiotherapy for 1 week versus 3 weeks (FAST-Forward): 5-year efficacy and late normal tissue effects results from a multicentre, non-inferiority, randomised, phase 3 trial
2020
We aimed to identify a five-fraction schedule of adjuvant radiotherapy (radiation therapy) delivered in 1 week that is non-inferior in terms of local cancer control and is as safe as an international standard 15-fraction regimen after primary surgery for early breast cancer. Here, we present 5-year results of the FAST-Forward trial.
FAST-Forward is a multicentre, phase 3, randomised, non-inferiority trial done at 97 hospitals (47 radiotherapy centres and 50 referring hospitals) in the UK. Patients aged at least 18 years with invasive carcinoma of the breast (pT1–3, pN0–1, M0) after breast conservation surgery or mastectomy were eligible. We randomly allocated patients to either 40 Gy in 15 fractions (over 3 weeks), 27 Gy in five fractions (over 1 week), or 26 Gy in five fractions (over 1 week) to the whole breast or chest wall. Allocation was not masked because of the nature of the intervention. The primary endpoint was ipsilateral breast tumour relapse; assuming a 2% 5-year incidence for 40 Gy, non-inferiority was predefined as ≤1·6% excess for five-fraction schedules (critical hazard ratio [HR] of 1·81). Normal tissue effects were assessed by clinicians, patients, and from photographs. This trial is registered at isrctn.com, ISRCTN19906132.
Between Nov 24, 2011, and June 19, 2014, we recruited and obtained consent from 4096 patients from 97 UK centres, of whom 1361 were assigned to the 40 Gy schedule, 1367 to the 27 Gy schedule, and 1368 to the 26 Gy schedule. At a median follow-up of 71·5 months (IQR 71·3 to 71·7), the primary endpoint event occurred in 79 patients (31 in the 40 Gy group, 27 in the 27 Gy group, and 21 in the 26 Gy group); HRs versus 40 Gy in 15 fractions were 0·86 (95% CI 0·51 to 1·44) for 27 Gy in five fractions and 0·67 (0·38 to 1·16) for 26 Gy in five fractions. 5-year incidence of ipsilateral breast tumour relapse after 40 Gy was 2·1% (1·4 to 3·1); estimated absolute differences versus 40 Gy in 15 fractions were −0·3% (−1·0 to 0·9) for 27 Gy in five fractions (probability of incorrectly accepting an inferior five-fraction schedule: p=0·0022 vs 40 Gy in 15 fractions) and −0·7% (−1·3 to 0·3) for 26 Gy in five fractions (p=0·00019 vs 40 Gy in 15 fractions). At 5 years, any moderate or marked clinician-assessed normal tissue effects in the breast or chest wall was reported for 98 of 986 (9·9%) 40 Gy patients, 155 (15·4%) of 1005 27 Gy patients, and 121 of 1020 (11·9%) 26 Gy patients. Across all clinician assessments from 1–5 years, odds ratios versus 40 Gy in 15 fractions were 1·55 (95% CI 1·32 to 1·83, p<0·0001) for 27 Gy in five fractions and 1·12 (0·94 to 1·34, p=0·20) for 26 Gy in five fractions. Patient and photographic assessments showed higher normal tissue effect risk for 27 Gy versus 40 Gy but not for 26 Gy versus 40 Gy.
26 Gy in five fractions over 1 week is non-inferior to the standard of 40 Gy in 15 fractions over 3 weeks for local tumour control, and is as safe in terms of normal tissue effects up to 5 years for patients prescribed adjuvant local radiotherapy after primary surgery for early-stage breast cancer.
National Institute for Health Research Health Technology Assessment Programme.
Journal Article
Partial-breast radiotherapy after breast conservation surgery for patients with early breast cancer (UK IMPORT LOW trial): 5-year results from a multicentre, randomised, controlled, phase 3, non-inferiority trial
by
Ciurlionis, Laura
,
Ebbs, Stephen
,
Winstanley, John
in
Breast - pathology
,
Breast cancer
,
Breast Neoplasms - pathology
2017
Local cancer relapse risk after breast conservation surgery followed by radiotherapy has fallen sharply in many countries, and is influenced by patient age and clinicopathological factors. We hypothesise that partial-breast radiotherapy restricted to the vicinity of the original tumour in women at lower than average risk of local relapse will improve the balance of beneficial versus adverse effects compared with whole-breast radiotherapy.
IMPORT LOW is a multicentre, randomised, controlled, phase 3, non-inferiority trial done in 30 radiotherapy centres in the UK. Women aged 50 years or older who had undergone breast-conserving surgery for unifocal invasive ductal adenocarcinoma of grade 1–3, with a tumour size of 3 cm or less (pT1–2), none to three positive axillary nodes (pN0–1), and minimum microscopic margins of non-cancerous tissue of 2 mm or more, were recruited. Patients were randomly assigned (1:1:1) to receive 40 Gy whole-breast radiotherapy (control), 36 Gy whole-breast radiotherapy and 40 Gy to the partial breast (reduced-dose group), or 40 Gy to the partial breast only (partial-breast group) in 15 daily treatment fractions. Computer-generated random permuted blocks (mixed sizes of six and nine) were used to assign patients to groups, stratifying patients by radiotherapy treatment centre. Patients and clinicians were not masked to treatment allocation. Field-in-field intensity-modulated radiotherapy was delivered using standard tangential beams that were simply reduced in length for the partial-breast group. The primary endpoint was ipsilateral local relapse (80% power to exclude a 2·5% increase [non-inferiority margin] at 5 years for each experimental group; non-inferiority was shown if the upper limit of the two-sided 95% CI for the local relapse hazard ratio [HR] was less than 2·03), analysed by intention to treat. Safety analyses were done in all patients for whom data was available (ie, a modified intention-to-treat population). This study is registered in the ISRCTN registry, number ISRCTN12852634.
Between May 3, 2007, and Oct 5, 2010, 2018 women were recruited. Two women withdrew consent for use of their data in the analysis. 674 patients were analysed in the whole-breast radiotherapy (control) group, 673 in the reduced-dose group, and 669 in the partial-breast group. Median follow-up was 72·2 months (IQR 61·7–83·2), and 5-year estimates of local relapse cumulative incidence were 1·1% (95% CI 0·5–2·3) of patients in the control group, 0·2% (0·02–1·2) in the reduced-dose group, and 0·5% (0·2–1·4) in the partial-breast group. Estimated 5-year absolute differences in local relapse compared with the control group were −0·73% (−0·99 to 0·22) for the reduced-dose and −0·38% (−0·84 to 0·90) for the partial-breast groups. Non-inferiority can be claimed for both reduced-dose and partial-breast radiotherapy, and was confirmed by the test against the critical HR being more than 2·03 (p=0·003 for the reduced-dose group and p=0·016 for the partial-breast group, compared with the whole-breast radiotherapy group). Photographic, patient, and clinical assessments recorded similar adverse effects after reduced-dose or partial-breast radiotherapy, including two patient domains achieving statistically significantly lower adverse effects (change in breast appearance [p=0·007 for partial-breast] and breast harder or firmer [p=0·002 for reduced-dose and p<0·0001 for partial-breast]) compared with whole-breast radiotherapy.
We showed non-inferiority of partial-breast and reduced-dose radiotherapy compared with the standard whole-breast radiotherapy in terms of local relapse in a cohort of patients with early breast cancer, and equivalent or fewer late normal-tissue adverse effects were seen. This simple radiotherapy technique is implementable in radiotherapy centres worldwide.
Cancer Research UK.
Journal Article
Real particle physics analysis by UK secondary school students using the ATLAS Open Data: an illustration through a collection of original student research
by
Olaiya, Emmanuel
,
Harris, Ynyr
,
Barr, Alan
in
Applied and Technical Physics
,
Atomic
,
Collaboration
2024
Since the 2020 release of
10
fb
-
1
of integrated luminosity of proton–proton collision data to the public by the ATLAS experiment, significant potential for its use for youth engagement in physics and citizen science has been present. In particular, this article aims to address whether, if provided adequate training and resources, high school students are capable of leveraging the ATLAS Open Data to semi-autonomously develop their own original research projects. To this end, a repository of interactive Python Jupyter notebook training materials was developed, incrementally increasing in difficulty; in the initial instalments no prior knowledge of particle physics or Python coding is assumed, while in the latter stages students emulate the steps of a real Higgs boson search using ATLAS data. This programme was implemented in secondary schools throughout the UK during the 2022/23 academic year and is presented in this article through a collection of research projects developed by a selection of participating students.
Journal Article
Improving Radiotherapy Treatments for Head and Neck Cancer Patients
2022
Radiotherapy for head and neck cancer is a highly complex, multi-step process that requires input from many different staff groups. The timeliness and quality of radiotherapy for head and neck cancer patients is essential in reaching the aims set out in the radiotherapy operational delivery network service specifications (NHS England, 2019). This thesis addresses the issues of timeliness and quality in radiotherapy for head and neck cancer patients.Timeliness has been addressed in a study of the impact waiting for radiotherapy to start has on overall survival and patient experience. The time between decision to treat with radiotherapy and the start of radiotherapy (TTS) was studied. A TTS greater than 30 days was found to be associated with a significant increase in death when compared to a TTS of less than 15 days. Patient responses to a questionnaire showed that the effect of waiting for radiotherapy to start is patient dependent and not time dependent. This study shows that focus should be on ensuring all patients are treated within a TTS of 30 days.In radiotherapy of the head and neck it is common for the clinical target volume (CTV) to extend to the patient’s skin. For inverse planning this results in excessive fluence being delivered to the build-up region and therefore the skin. A study has been carried out to determine a planning solution that gives superior plan quality when considering CTV coverage, skin dose and plan robustness. This study shows that a virtual bolus planning method was superior to the other common techniques considered.In the planning study an accurate Eclipse Acuros XB calculation of dose at the surface and in the build-up region was assumed. A novel dosimeter for surface dosimetry has been used to study the differences in skin dose found in the planning study. DOSEmappersTM are a 2D array of Micro Silica Bead TLDs. This study has shown that the Bead TLDs have an effective depth of measurement of 0.7 mm and when constructed as a DOSEmapperTM make an ideal near surface dosimeter. Measurements using DOSEmappersTMconfirm the dose differences from different planning approaches used in the planning study. This gives confidence in determining the most superior planning method for head and neck VMAT planning.This work contributes to the field of head and neck cancer radiotherapy. The time head and neck cancer patients should be treated within and a planning method that gives superior plan quality have been determined and validated.
Dissertation
Contributing factors to muscle weakness in children with cerebral palsy
by
Cook, Kathryn
,
Elder, Geoffrey CB
,
Leahey, Lorne
in
Cerebral Palsy
,
Cerebral Palsy - complications
,
Child
2003
The aim of this study was to determine the extent of ankle muscle weakness in children with cerebral palsy (CP) and to identify potential causes. Maximal voluntary contractions of plantar (PF) and dorsiflexors (DF) were determined at optimal angles in knee flexion and extension in both legs of 14 children with hemiplegia (7 males, 7 females) and 14 with diplegia (8 males, 6 females). Their results were compared to 14 age- and weight-matched control participants (5 males, 9 females). Muscle cross-sectional areas of soleus, posterior, and anterior compartment muscles were determined from MRIs in 14 children with CP (eight diplegia, six hemiplegia) and 18 control children. Specific tension (torque/unit area) of PF and DF was determined from torque and cross-sectional area results. Muscle volumes of PF and DF were also determined in both legs of five control children and five with hemiplegia. Muscle EMG was recorded from soleus, medial gastrocnemius, and tibialis anterior during each maximal voluntary contraction. Mean amplitude was significantly reduced in PF and DF in both CP groups and significantly higher levels of coactivation of antagonists were found compared to control participants. Strength of PF and DF was significantly reduced in both CP groups, but more importantly the muscles were found to be weak based on significantly reduced specific tensions. The PF were most affected, particularly in the group with hemiplegia. It is believed that an inability to maximally activate their muscles contributed to this weakness. A combination of incomplete activation and high levels of PF coactivation are thought to have contributed to DF weakness.
Journal Article
Developing, implementing, and evaluating the visiting Neighbors’ program in rural Appalachia: A quality improvement protocol
2024
Older adults living alone in rural areas frequently experience health declines, social isolation, and limited access to services. To address these challenges, our medical academic university supported a quality improvement project for developing and evaluating the Visiting Neighbors program in two rural Appalachian counties. Our Visiting Neighbors program trained local volunteers to visit and guide rural older adults in healthy activities. These age-appropriate activities (Mingle, Manage, and Move- 3M's) were designed to improve the functional health of older adults. The program includes four in-home visits and four follow-up telephone calls across three months.
The purpose of this paper was to describe the 3M's Visiting Neighbors protocol steps guiding the quality improvement procedures relating to program development, implementation, and evaluation.
This Visiting Neighbors study used a single-group exploratory quality improvement design. This program was tested using quality improvement standards, including collecting participant questionnaires and visit observations.
Older adults (> 65 years) living alone (N = 30) participants were female (79%) with a mean age of 82.96 (SD = 7.87) years. Volunteer visitor participants (N = 10) were older adult females. Two volunteer visitors implemented each visit, guided by the 3M's activities manual. All visits were verified as being consistently delivered (fidelity). Enrollment and retention data found the program was feasible to conduct. The older adult participants' total program helpfulness ratings (1 to 5) were high (M = 51.27, SD = 3.77). All volunteer visitor's program helpfulness ratings were also high (M = 51.78, SD = 3.73).
The Visiting Neighbors program consistently engaged older Appalachian adults living alone in the 3M's activities. The feasibility and fidelity of the 3M's home visits were verified. The quality improvement processes included engaging the expert advisory committee and rural county stakeholders to ensure the quality of the program development, implementation, and evaluation.
Journal Article
The effectiveness of a community-based diabetes patient education program
1999
The purpose of this study was to examine the relationship between a community-based diabetes education program and control of glycosylated hemoglobin and body weight in patients with Type 2 diabetes. Roy's adaptation model of nursing provided the theoretical framework for this study. A convenience sample of 31 adults with Type 2 diabetes were recruited from an outpatient endocrinologist's office that offered a community-based diabetes education program. A one-group pre and post quasi-experimental investigation was conducted to ascertain changes in glycosylated hemoglobin and body weight. Data collection was conducted by retrospective record audit at three months, six months, and one year post-intervention. A paired t test was used to analyze the variations in the glycosylated hemoglobin and body weight over time. Findings showed statistically significant lower glycosylated hemoglobin levels post-intervention at the three month, six month, and one year check points. No statistically significant differences were found in post-intervention body weight measurements except for those subjects who had had diabetes less than ten years. These subjects' data approached statistical significance for the weight loss at six months post-intervention. Findings suggest that the community-based education program was effective in helping patients achieve improved blood glucose control.
Dissertation