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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 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.

Thrace had and has relatively favor conditions for substantial development, that is, good and adequate physical, environmental and cultural resources, but paradoxically remains the poorest Greek region. What missed was the smart, consistent and effective regional development policies, capable of counterbalancing the disadvantages. Some not well-designed policies, based on generous financial incentives after 1976, contributed very little to its growth because they were fragmentary without focus and cohesion. They supported a shallow growth, unable to create a good/stable and sustainable basis for cost, quality and functional competitive advantages. Our empirical research proves well- documented the insufficiency of regional policies followed the last 40 years, 1976-2015. In this context, we suggest some indicative new regional policies that will have to be based on both, in smart incentives, supporting smart/flexible specialization well-branded globally and in intelligent production systems capable of supporting effectively, either outsourcing production via long term cooperation, or domestic production for niche markets.

Introduction: Accidental pediatric liquid paracetamol exposure is common. Most children do not require treatment with acetylcysteine and acute liver injury is rare.Case report: An otherwise well 3-...

Purpose Dose–volume histogram (DVH) measurements have been integrated into commercially available quality assurance systems to provide a metric for evaluating accuracy of delivery in addition to gamma analysis. We hypothesize that tumor control probability and normal tissue complication probability calculations can provide additional insight beyond conventional dose delivery verification methods. Methods A commercial quality assurance system was used to generate DVHs of treatment plan using the planning CT images and patient‐specific QA measurements on a phantom. Biological modeling was performed on the DVHs produced by both the treatment planning system and the quality assurance system. Results The complication‐free tumor control probability, P +, has been calculated for previously treated intensity modulated radiotherapy (IMRT) patients with diseases in the following sites: brain (−3.9% ± 5.8%), head‐neck (+4.8% ± 8.5%), lung (+7.8% ± 1.3%), pelvis (+7.1% ± 12.1%), and prostate (+0.5% ± 3.6%). Conclusion Dose measurements on a phantom can be used for pretreatment estimation of tumor control and normal tissue complication probabilities. Results in this study show how biological modeling can be used to provide additional insight about accuracy of delivery during pretreatment verification.

The structural development interventions carried out by the European Union (EU) aim to accelerate the real convergence of 28 Member States, mainly those lagging behind interventions. Most of these contribute to better environmental protection, better life condition for farmers and flood protection. Evaluation of infrastructure projects contributing to spatial growth in ex-ante, ongoing, and ex-post basis is an essential activity to answer several issues raised during the growth mentioned above process. This paper aims to evaluate on ex-post basis integrated developmental interventions-large scale infrastructure projects in rural areas, using a combined method based on Social Cost-Benefit Analysis (SCBA), sustainable and rural growth indicators coming from official organizations along with the n-Dimensional (nD) modelling. The studied developmental interventions refer to Vistonida's rural area, an area to which large-scale infrastructure financed and carried out by the Greek state. They contributed to the modernization and adaptation of the agriculture sector, improving its qualitative and quantitative performance. The needed data derived from the Hellenic National Statistical Services, Ministry of Agriculture, Greek Payment Authority of Common Agricultural Policy (C.A.P.) and concern a period of forty years and they are referred to Land redistribution, irrigation land, crops structure. According to this study, the large-scale agriculture infrastructure contributes significantly to the improvement of the growth rates of a rural spatial productive system as a whole. The application of the combined method was simple, easily understood by policymakers, adequately reliable, and precise.

Background: The increased use of deformable registration algorithms in clinical practice has also increased the need for their validation. Aims and Objectives: The purpose of the study was to investigate the quality, accuracy, and plausibility of three commercial image registration algorithms for 4-dimensional computed tomography (4DCT) datasets using various similarity measures. Materials and Methods: 4DCT datasets were acquired for 10 lung cancer patients. 23 similarity measures were used to evaluate image registration quality. To ensure selected method's invertibility and assess resultant mechanical stress, the determinant of the Jacobian for the displacement field and 3-D Eulerian strain tensor were calculated. All the measures and calculations were applied on to extended deformable multi pass (EXDMP) and deformable multi pass (DMP) methods. Results: The results indicate the same trend for several of the studied measures. The Jacobian determinant values were always positive for the DMP method. The Eulerian strain tensor had smaller values for the DMP method than EXDMP in all of the studied cases. The negative values of the Jacobian determinant point to non-physical behavior of the EXDMP method. The Eulerian strain tensor values indicate less tissue strain for the DMP method. Large differences were also observed in the results between complete and cropped datasets (coefficient of determination: 0.55 vs. 0.93). Conclusion: A number of error and distance measures showed the best performance among the tested measures. The evaluated measures might detect CT dataset differences with higher precision if the analysis is restricted to a smaller volume.

Cities are increasingly dependent on networks, sensors, and microcontrollers. Artificial intelligence has managed to mimic human behavior, and in a few years, many jobs may be replaced by computers or machines. Today, smart cities are evolving in all countries from the poorest to the most economically viable, and there are many smart city applications that rely on observation and participation of the citizens. Active citizens are interested in the benefits of their city, and they are involved in improving and promoting urban living. All levels of smart citizen participation are associated with liberal citizenship and personal autonomy and the choice of individuals to perform specific roles and take responsibility for their actions. The states in turn provide liberal forms of government. Smart cities need “smart people” who can take an active part in both governance and city reform. This kind of citizen participation is more than just a ritual participation in government.

Objective. The aim of this work is an AI based approach to reduce the volume effect of ionization chambers used to measure high energy photon beams in radiotherapy. In particular for profile measurements, the air-filled volume leads to an inaccurate measurement of the penumbra. Approach. The AI-based approach presented in this study was trained with synthetic data intended to cover a wide range of realistic linear accelerator data. The synthetic data was created by randomly generating profiles and convolving them with the lateral response function of a Semiflex 3D ionization chamber. The neuronal network was implemented using the open source tensorflow.keras machine learning framework and a U-Net architecture. The approach was validated on three accelerator types (Varian TrueBeam, Elekta VersaHD, Siemens Artiste) at FF and FFF energies between 6 MV and 18 MV at three measurement depths. For each validation, a Semiflex 3D measurement was compared against a microDiamond measurement, and the AI processed Semiflex 3D measurement was compared against the microDiamond measurement. Main results. The AI approach was validated with dataset containing 306 profiles measured with Semiflex 3D ionization chamber and microDiamond. In 90% of the cases, the AI processed Semiflex 3D dataset agrees with the microDiamond dataset within 0.5 mm/2% gamma criterion. 77% of the AI processed Semiflex 3D measurements show a penumbra difference to the microDiamond of less than 0.5 mm, 99% of less than 1 mm. Significance. This AI approach is the first in the field of dosimetry which uses synthetic training data. Thus, the approach is able to cover a wide range of accelerators and the whole specified field size range of the ionization chamber. The application of the AI approach offers an quality improvement and time saving for measurements in the water phantom, in particular for large field sizes.

Background and Objectives: To evaluate the influence of obstructive sleep apnea (OSA)-related symptoms on prevalent cardiovascular disease (CVD) in a large clinical population of patients. Materials and Methods: A total of 2127 patients (mean age 55 years, 24% women) underwent diagnostic polysomnography and were evaluated using the Epworth sleepiness scale (ESS), the Athens Insomnia Scale (AIS), and the Beck Depression Inventory (BDI). We investigated the predictive value of OSA-associated symptoms for prevalent cardiovascular disease, after adjustment for relevant confounding factors including age, obesity, and co-morbidities. Results: Patients with OSA and CVD were older and had a higher Body Mass Index (BMI), the percentage of obese patients was also higher (83% vs. 70%, p &lt, 0001). They also had greater neck, waist, and hip circumferences and a higher waist-to-hip ratio. Excessive daytime sleepiness (ESS ≥ 10) [odds ratio (95% CI) 1.112 (0.708–1.748), p = 0.64], insomnia symptoms (AIS ≥ 6) [odds ratio (95% CI) 0.748 (0.473–1.184), p = 0.21], frequent awakenings [odds ratio (95% CI) 1.599 (1.019–2.508), p = 0.06], and nocturia [odds ratio (95% CI) 1.359 (0.919–2.009), p = 0.124] were not associated with CVD after adjustment for the previous confounders. On the other hand, depressive symptoms (BDI ≥ 10) independently predicted prevalent CVD [odds ratio (95% CI) 1.476 (1.154–1.887), p = 0.002]. Further analysis in subgroups stratified by age, BMI, and gender demonstrated that depressive symptoms predicted prevalent CVD but only in the subgroup of younger (age group &lt, 60 years), obese (BMI group ≥ 30), and male (OR = 1.959, 95% CI = 1.209–3.175, p = 0.006) OSA patients. Conclusions: OSA patients with CVD were more likely to complain of less typical OSA symptoms and depressive symptoms compared to patients without CVD in this large clinical patient cohort, supportingthecomplexity and heterogeneityof OSA.

Predation ability is a key component determining the suppression of agricultural pests by natural enemies. The aim of this study is to evaluate the effect of prey density and developmental stage on the predation of Euseius scutalis (Acari: Phytoseiidae) on the two-spotted spider mite, Tetranychus urticae (Acari: Tetranychidae) and the oriental red mite, Eutetranychus orientalis (Acari: Tetranychidae). For this purpose, laboratory functional response experiments were conducted using female adults of E. scutalis. Results indicated that the predator causes an inverse density dependent mortality to larvae, nymphs and adults of the two-spotted spider mite, as well as the oriental red mite. The random predator equation was used to fit the data. E. scutalis handling time increased significantly with T. urticae and E. orientalis developmental stage. The maximum number of T. urticae prey consumed was 48.3 larvae, 28.5 nymphs and 11.0 adults, where the corresponding values for E. orientalis were 48.8, 32.2 and 18.2 larvae, nymphs and adults, respectively. Estimated handling times and attack rates of E. scutalis on larvae, nymphs and adults of T. urticae were 0.4970 h and 0.1058 h-1, 0.8435 h and 0.1395 h-1, and 2.1834 h and 0.0835 h-1, respectively. The corresponding values on larvae, nymphs and adults of E. orientalis were 0.4920 h and 0.1166 h-1, 0.7452 h and 0.1361 h-1, and 1.3186 h and 0.0597 h-1, respectively. The results of this study may be indicative of the predation ability of adults of E. scutalis on these notorious pests, providing a basis for determining release rates appropriate for various pest densities.

Truck drivers are a vulnerable population due to the high number of workplace injuries and fatalities predominant in their occupation. In Australia, the road freight transportation industry has been identified as a national priority area in terms of creating preventative measures to improve the health and safety of its workers. With an environment conducive to poor nutritional food choices and unhealthy lifestyle behaviours, many barriers exist to creating a safe and healthy workforce. Thus, the current study aimed to describe the pre-injury hospital-recorded health conditions and health service use of truck drivers with a worker’s injury compensation claim/s when compared to workers in other industries. Data was obtained from a compensation claims database and linked with hospital admissions data recorded five years prior to the injury claim. Health and lifestyle behaviour data for the occupational code of truck drivers was compared to other occupational drivers, as well as to all other occupations. Analysis was conducted via logistic regression. The results found that when compared to other occupational drivers, truck drivers were significantly more likely to have a hospital-recorded diagnosis of diabetes and/or hypertension, as well as being significantly more likely to have a hospital record of tobacco use and/or alcohol misuse/abuse. The findings show that there is a need to review and revise existing health strategies to promote the health and wellbeing of truck drivers, especially given their challenging work environment.

Introduction and Aims The COVID-19 pandemic has had an unprecedented impact on service provision in Emergency General Surgery. Due to the unknown risk of COVID-19 transmission, the use of laparoscopic surgery was cautioned against in favour of open surgery or conservative management. This study looks at the impact of service reconfiguration on rates of laparoscopic surgery. Methods The management and outcomes were audited of all patients admitted to our unit during the UK COVID-19 lockdown period and compared against the same period last year. Results In total, 645 patients (223 COVID-19 period, 422 non-COVID) were included. Less surgery was performed during the pandemic (32.3% vs 39.3%), with only 2 cases of laparoscopic surgery (0.9% vs 16.1%). Despite a change to conservative management, we report no differences in complication rates or length of stay and 30-day mortality (excluding deaths from COVID-19 pneumonitis). Re-admission rates were higher following conservative management (10.6% vs 4.7%). Conclusion There is a significant reduction in surgery (particularly laparoscopic surgery) during the COVID-19 pandemic. There are no differences in outcomes, but we show higher re-admission rates for patients treated conservatively. Together with emerging evidence on the safety of laparoscopic surgery, these findings help inform service re-configuration for future pandemic responses.

Aims This study assesses the impact of COVID-19 on the presentation and management of acute appendicitis (AA). Patients presenting with AA during the first wave of the COVID-19 pandemic are compared to a pre-COVID-19 cohort. Methods Patients admitted to a single acute NHS hospital with AA between April and July in 2019 and 2020 were retrospectively identified. Data on presentation, treatment and outcomes was collected. Results 56 patients were identified in 2019, and 37 in 2020. A greater proportion of patients presented later (>3 days of symptoms) in 2020 (2019=15.6%, 2020=32.4%, p 50 and white cell count > 15). In 2020, more patients were managed conservatively (2019=7.1%, 2020=35.1%, p Conclusions AA patients in the COVID-19 pandemic were more likely to present later and were more likely to be managed conservatively or with open appendicectomy. There was a higher rate of post-operative complications for patients in 2020. Duration of stay and readmission rates were similar.

Aims Frailty is associated with high morbidity following emergency laparotomy. Objective scores such as P-POSSUM are well recognised in predicting outcomes such as morbidity and mortality. Qualitative factors affecting recovery and rehabilitation are less established. This review explores the lived experiences of elderly patients following emergency laparotomy to identify factors to improve post-hospital care. Methods A systematic review of the medical and nursing literature was performed using MEDLINE, Web of Science Core Collection and CINAHL Plus in January 2020. Qualitative and phenomenological studies were identified using keywords ‘emergency’, ‘laparotomy’, ‘abdo*’ and ‘surgery’. Cancer studies were excluded. Themes were extracted for ‘lines of argument’ synthesis to build a general interpretation of findings. The review is registered with PROSPERO (CRD42019159751). Results The search identified 569 unique citations of which 551 were excluded after screening and 17 excluded following full-text review. One study was included (Thomsen et al, 2014) exploring postoperative care for 18 patients following emergency abdominal surgery. Thematic analysis was limited to the hospital setting. Patients described Critical Care as a safe environment for recovery and rehabilitation because of higher nursing ratios. Patients placed emphasis on ready access to staff and timely interventions which was particularly poor on surgical wards. Specific barriers, particularly patient concerns regarding recovery, were not explored. Conclusions This review highlights the importance of easy access to staff and inpatient services following emergency laparotomy but demonstrates the lack of qualitative evidence exploring the lived experience of the immediate post-discharge period that impacts on rehabilitation back to normal activities.

Background The COVID-19 pandemic is a global public health emergency. The reconfiguration of local healthcare systems to accommodate the increase in Critical Care capacity has put strain on ‘non-COVID’ specialities. This study characterises the utilisation of Emergency General Surgery (EGS) services at a busy UK university teaching hospital during the COVID-19 lockdown period to evaluate outcomes and to identify patient groups with worse outcomes. Method This retrospective study compares EGS admissions during the UK’s lockdown period (23rd March-28th May 2020) to the same period in 2019. Patient demographics were recorded together with details of their hospital stay and treatment outcomes. Results A total of 645 patients were included, comprising 223 in the COVID-19 and 422 in the non-COVID-19 periods. There was no difference in age, sex, co-morbidity or socioeconomical status. A lower proportion of Black, Asian and Minority Ethnic (BAME) patients were admitted during the COVID-19 period (20.6% vs 35.4%, p Conclusion We show that the UK reorganisation of EGS services has been successful in terms of outcomes and access to services despite a more unwell population. There was a lower proportion of BAME admissions suggesting additional barriers to access to healthcare under pandemic lockdown conditions.

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.

The aim of this study was to measure and compare the output factor (OF) of a CyberKnife Robotic Radiosurgery System with eight different small field detectors and validate with Technical Report Series (TRS) report 483.Accurate dosimetry of CyberKnife system is limited due to the challenges in small field dosimetry. OF is a vital dosimetric parameter used in the photon beam modeling and any error would affect the dose calculation accuracy.In this study, the OF was measured with eight different small-field detectors for the 12 IRIS collimators at 800 mm SAD setup at 15 mm depth. The detectors used were PTW 31016 PinPoint 3D, IBA PFD shielded diode, IBA EFD unshielded diode, IBA SFD unshielded diode (stereotactic), PTW 60008 shielded diode, PTW 60012 unshielded diode, PTW 60018 unshielded diode (stereotactic), and PTW 60019 CVD diamond detector. OF was obtained after correcting for field output correction factors from IAEA TRS No. 483.The field OFs in CyberKnife are derived from the measured data by applying the correction factors from Table 23 in TRS 483 for the eight small field detectors. These field OFs matched within 2% of peer-reviewed published values. The range and standard deviation showed a decreasing trend with collimator diameter.The field OF obtained after applying the appropriate correction factor from TRS 483 matched well with the peer-reviewed published OFs. The inter-detector variation showed a decreasing trend with increasing collimator field size. This study gives physicists confidence in measuring field OFs while using small field detectors mentioned in this work.