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Automatic FDG-PET-based tumor and metastatic lymph node segmentation in cervical cancer

Treatment of cervical cancer, one of the three most commonly diagnosed cancers worldwide, often relies on delineations of the tumour and metastases based on PET imaging using the contrast agent 18F-Fluorodeoxyglucose (FDG). We present a robust automatic algorithm for segmenting the gross tumour volume (GTV) and metastatic lymph nodes in such images. As the cervix is located next to the bladder and

A treatment planning and delivery comparison of volumetric modulated arc therapy with or without flattening filter for gliomas, brain metastases, prostate, head/neck and early stage lung cancer

Background. Flattening filter-free (FFF) beams are an emerging technology that has not yet been widely implemented as standard practice in radiotherapy centers. To facilitate the clinical implementation of FFF, we attempted to elucidate the difference in plan quality and treatment delivery time compared to flattening filter beams (i.e. standard, STD) for several patient groups. We hypothesize that

18F-FDG PET/CT for planning external beam radiotherapy alters therapy in 11% of 581 patients

Background: 18F-FDG PET/CT (FDG PET/CT) used in radiotherapy planning for extra-cerebral malignancy may reveal metastases to distant sites that may affect the choice of therapy. Aim: To investigate the role of FDG PET/CT on treatment strategy changes induced by the use of PET/CT as part of the radiotherapy planning. ‘A major change of treatment strategy’ was defined as either including more lesion

Feasibility of Pencil Beam Scanned Intensity Modulated Proton Therapy in Breath-hold for Locally Advanced Non-Small Cell Lung Cancer

Purpose We evaluated the feasibility of treating patients with locally advanced non-small cell lung cancer (NSCLC) with pencil beam scanned intensity modulated proton therapy (IMPT) in breath-hold. Methods and Materials Fifteen NSCLC patients who had previously received 66 Gy in 33 fractions with image guided photon radiation therapy were included in the present simulation study. In addition to a

Simulating intrafraction prostate motion with a random walk model

Purpose Prostate motion during radiation therapy (ie, intrafraction motion) can cause unwanted loss of radiation dose to the prostate and increased dose to the surrounding organs at risk. A compact but general statistical description of this motion could be useful for simulation of radiation therapy delivery or margin calculations. We investigated whether prostate motion could be modeled with a ra

Target position uncertainty during visually guided deep-inspiration breath-hold radiotherapy in locally advanced lung cancer

Purpose The purpose of this study was to estimate the uncertainty in voluntary deep-inspiration breath-hold (DIBH) radiotherapy for locally advanced non-small cell lung cancer (NSCLC) patients. Methods Perpendicular fluoroscopic movies were acquired in free breathing (FB) and DIBH during a course of visually guided DIBH radiotherapy of nine patients with NSCLC. Patients had liquid markers injected

Investigation on work hardening phenomenon in turning Inconel 718 with chamfered inserts considering thermal-mechanical loads

Work hardening layer on and beneath the machined surface is one of the key factors that affects the performance and service time of the final component. However, the mechanism of the work hardening generation and its behavior are still great challenges and open issues to the academic and industry. In this paper, an investigation of the work hardening layer generated by chamfered tools is conducted

Local error estimation and step size control in adaptive linear multistep methods

In a k-step adaptive linear multistep methods the coefficients depend on the k − 1 most recent step size ratios. In a similar way, both the actual and the estimated local error will depend on these step ratios. The classical error model has been the asymptotic model, chp+ 1y(p+ 1)(t), based on the constant step size analysis, where all past step sizes simultaneously go to zero. This does not refle

Feminization of complex traits in Drosophila melanogaster via female-limited X chromosome evolution

A handful of studies have investigated sexually antagonistic constraints on achieving sex-specific fitness optima, although exclusively through male-genome-limited evolution experiments. In this article, we established a female-limited X chromosome evolution experiment, where we used an X chromosome balancer to enforce the inheritance of the X through the matriline, thus removing exposure to male

Simulated rhizosphere deposits induce microbial N-mining that may accelerate shrubification in the subarctic

Climate change is exposing high-latitude systems to warming and a shift towards more shrub-dominated plant communities, resulting in increased leaf-litter inputs at the soil surface, and more labile root-derived organic matter (OM) input in the soil profile. Labile OM can stimulate the mineralization of soil organic matter (SOM); a phenomenon termed “priming.” In N-poor subarctic soils, it is hypo

A framework for exploring blockchain technology in supply chain management

The purpose of the study is to identify and explore different applications of blockchain technology in supply chain management and suggest a framework for their analysis. The study addresses researchers' conflicting opinions regarding the hype of blockchain and clarifies which minor applications are hyped and which are currently more applicable. That helps supply chain practitioners appraise the d

Loss of NF2 defines a genetic subgroup of non-FOS-rearranged osteoblastoma

Osteoblastoma is a locally aggressive tumour of bone. Until recently, its underlying genetic features were largely unknown. During the past two years, reports have demonstrated that acquired structural variations affect the transcription factor FOS in a high proportion of cases. These rearrangements modify the terminal exon of the gene and are believed to stabilise both the FOS transcript and the

Role of fine needle aspiration cytology in the diagnosis of soft tissue tumours

Fine needle aspiration cytology (FNAC) is a widely accepted safe, simple and rapid diagnostic procedure used in the examination of neoplastic and non-neoplastic lesions of various locations. Since its introduction, FNAC has developed into an effective diagnostic tool practiced in a large majority of medical centres evaluating and treating oncological patients. The role of FNAC has been limited in

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Cellular composition and morphology of components of photoreceptor apparatus of the retinae of camera eyes of some species of terrestrial gastropod pulmonate molluscs were studied and its evolutionary transformations were traced. It was demonstrated that all examined characteristics of photoreceptor apparatus of the most investigated species were normal for terrestrial pulmonates, while those of o

International cooperation for decarbonizing energy intensive industries – Towards a Green Materials Club : A working paper on sectoral cooperative approaches

The energy intensive industry, producing basic materials, is responsible for 25 to 30% of today's global greenhouse gas emissions. The future supply of GHG neutral basic materials (e.g. steel, cement, aluminium, plastics, etc.) is a necessity for building a sustainable modern society. Deep decarbonisation of the energy intensive industries is technically possible but will require a major systemic The energy intensive industry, producing basic materials, is responsible for 25 to 30% of today's global greenhouse gas emissions. The future supply of GHG neutral basic materials (e.g. steel, cement, aluminium, plastics, etc.) is a necessity for building a sustainable modern society. Deep decarbonisation of the energy intensive industries is technically possible but will require a major systemic

Assessing Low Carbon Transitions : A Conceptual Model

The present report presents a conceptual assessment model or framework for policy relevant analysis of low carbon transitions. The aim of the study is not to present specific guidelines for how to design assessments of low carbon transitions, but rather to give food for thought on aspects that should be regarded in the design process. The exact design would then depend on the purpose of the assess

Evidence-based Anti-seizure Monotherapy in Newly Diagnosed Epilepsy: a New Approach

ObjectivesTo describe the process and results of the updated Swedish practice guidelines for monotherapy in epilepsy.Materials and MethodsThe Swedish Medical Products Agency led the process together with medical experts. Evidence rating in accordance with the International League Against Epilepsy (ILAE) template was linked to the Cochrane group's GRADE system. Evidence from recently published tria

Sektorsansvar och energiberedskap : Förslag till arbetsmodell för att utforma ett sektorsansvar med förmågor i fokus

Den återupptagna totalförsvarsplaneringen med syfte att öka beredskapen inför kriser och krig innebär ökade ansträngningar för många samhällsaktörer med olika roller, ansvar och uppgifter. Detta har aktualiserat behovet av ett förtydligat sektorsansvar.I denna rapport diskuteras vilka beståndsdelar ett sektorsansvar kan ha, med energisektorn som exempel, inklusive de styrningskedjor som kan använd