scholarly journals Clinical implementation and initial experience with a 1.5 Tesla MR-linac for MR-guided radiotherapy for gynecologic cancer: An R-IDEAL stage 1/2a first in humans/feasibility study of new technology implementation

Author(s):  
David S Lakomy ◽  
Jinzhong Yang ◽  
Sastry Vedam ◽  
Jihong Wang ◽  
Belinda Lee ◽  
...  

Purpose: Magnetic resonance imaging-guided linear accelerator systems (MR-linacs) can facilitate the daily adaptation of radiotherapy plans. Here, we report our early clinical experience using an MR-linac for adaptive radiotherapy of gynecologic malignancies. Methods and Materials: Treatments were planned with an Elekta Monaco v5.4.01 and delivered by a 1.5 Tesla Elekta Unity MR-linac. The system offers a choice of daily adaptation based on either position (ATP) or shape (ATS) of the tumor and surrounding normal structures. The ATS approach has the option of manually editing the contours of tumors and surrounding normal structures before the plan is adapted. Here we documented the duration of each treatment fraction; set-up variability (assessed by isocenter shifts in each plan) between fractions; and, for quality assurance, calculated the percentage of plans meeting the ;γ-criterion of 3%/3-mm distance to agreement. Deformable accumulated dose calculations were used to compare ATP plans with reference dose plans. Results: Of the 10 patients treated with 90 fractions on the MR-linac, most received boost doses to recurrence in nodes or isolated tumors. Each treatment fraction lasted a median 32 minutes; fractions were shorter with ATP than with ATS (30 min vs 42 min, P<0.0001). The γ-criterion for all fraction plans exceeded >90% (median 99.9%, range 92.4%-100%), i.e., all plans passed quality assurance testing. The average extent of isocenter shift was <0.5 cm in each axis. The accumulated dose to the gross tumor volume was within 10% of the reference plan for all ATP cases. Accumulated doses for lesions in the pelvic periphery were within 1% of the reference plan as opposed to -5.8% to -9.6% for central tumors. Conclusions: The MR-linac is a reliable and clinically feasible tool for treating patients with gynecologic cancer.

Author(s):  
Martin Verlaan ◽  
Annette Zijderveld ◽  
Hans de Vries ◽  
Jan Kroos

The accurate forecasting of storm surges is an important issue in the Netherlands. With the emergence of the first numerical hydrodynamic models for surge forecasting at the beginning of the 1980s, new demands and possibilities were raised. This article describes the main phases of the development and the present operational set-up of the Dutch continental shelf model, which is the main hydrodynamic model for storm surges in the Netherlands. It includes a brief discussion of applied data-assimilation techniques, such as Kalman filtering, the model calibration process and some thoughts on quality assurance in an operational environment. After further describing some select recent investigations, the paper concludes with some remarks on future developments in a European context.


2021 ◽  
Author(s):  
Mihaela Vlaicu ◽  
Vasile Marius Nae ◽  
Patrick Christian Buerssner ◽  
Stefan Liviu Firu ◽  
Natalya Logashova

Abstract Paraffin represents one of the main case of failures and production losses which facing the entire oil industry. Prevention of paraffin deposition on the subsurface/surface equipment can be achieved by keeping the paraffin dissolved in crude oil or minimizing the adhesion or aggregation process of wax crystals. The paraffin problems which occur, conduct to gradual reduction of the tubular and pipelines internal diameter, restriction or valves blockages, and reduce the equipment capacity until the production is stop. Problems due to paraffin deposition varies and is different according with each commercial field, sometime the difference is from a well to well which producing from the same reservoir with different consistency. How we shall proceed? Before or after paraffin is field on the equipment? How could be avoid the future paraffin deposition? How long the selected method is proper for well ? The decision represents a combination based on oil's chemical & physical characteristics, well's behavior, method selected for prevention or elimination and combined with economic analysis and field experience. The paraffin inhibition applying is a common practice in OMV Petrom, which cover majority of the production wells. For the special wells, which the paraffin inhibition didn't provided satisfying results (multiple intervention due to paraffin deposition) was selected the Down Hole Heating technology (DHH) which was successfully tested in our company since 2014 thanks according with the yearly New Technology Program. The operating principle consists in heating the fluid volume from tubing using the heating cable which can be installed inside tubing, for NF and ESP wells or outside tubing for SRP or PCP wells. The cable is designed and located at the interval of wax crystallization appearance and heats the fluid to the temperature higher than the wax crystallization point (WAT). Since then, the DHH technology had an upward course, proven by high run life (highest value 2500 days / average 813 days) of the technology at the total 47 wells equipped, until this moment. Based on the successful results, recorded of 64% of old production wells equipped, it was decided to apply the technology at first completion of the new wells (36%), thus ensuring the protection of the new equipment. The paper offers an overview of DHH technology implementation, achievements, benefits and online monitoring of technology implementation starting with 2014 until today. The total impact shown a decreasing of no.of failures with 73,8%, the cost of intervention with 76,5%. The production losses decreased only with 5%, which certifies the fact that the technology helping production maintaining during the exploitation in comparison with production losses due paraffin issues recorded at wells without equipped with DHH technology. During 6 years of down hole heating technology application were developed candidate selection decision tree, monitoring the electrical efficiency, using the adaptability capacity of the technology from one well to another and integrate the temperature parameters in online monitoring system as part of digitalization concept of OMV Petrom, aspects which will be present in this article.


2018 ◽  
Vol 15 (6) ◽  
pp. 172988141881213 ◽  
Author(s):  
Brahim Brahmi ◽  
Maarouf Saad ◽  
Abdelkrim Brahmi ◽  
Cristobal Ochoa Luna ◽  
Mohammad Habibur Rahman

Rehabilitation robots are a new technology dedicated to the physiotherapy and assistance motion and has aroused great interest in the scientific community. These kinds of robots have shown a high potential in limiting the patient’s disability, increasing its functional movements and helping him/her in daily living activities. This technology is still an emerging area and suffers from many challenges like compliance control and human–robot collaboration. The main challenge addressed in this research is to ensure that the exoskeleton robot provides an appropriate compliance control that allows it to interact perfectly with humans. This article investigates a new compliant control based on a second-order sliding mode with adaptive-gain incorporating time delay estimation. The control uses human inverse kinematics to complete active rehabilitation protocols for an exoskeleton robot with unknown dynamics and unforeseen disturbances. The stability analysis is formulated and demonstrated based on Lyapunov function. An experimental physiotherapy session with three healthy subjects was set up to test the effectiveness of the proposed control, using virtual reality environment.


Author(s):  
Rachid ELKACHRADI

The university reform in Morocco introduced principles of quality assurance into the Higher Education System. In this regard, the law 01-00 has set up a device which is mainly articulated around the establishment of a system of accreditation of training and the establishment of a global system of evaluation in the whole system. However, Human Resources Management, the keystone of any change project, is not put at the center of the operationalization of reform projects. In our research, we will look at the factors that impede the operationalization of the principles of quality assurance to improve the effectiveness and efficiency of the HR function. Based on the results obtained within the framework of this exploratory study, we let's propose the key determinants for the implementation of a quality approach in Human Resources Management within Moroccan universities.


2019 ◽  
Vol 2 (4) ◽  
pp. 294
Author(s):  
Sarah Mansour

Creativity has been assigned to the design or drawing, with materials most often being specified as a result of design rather than being considered a driver of it. Designers empowered by new technology now consider form as it is defined by identifiable systems. This evidence based, parametric methodology is a response to two decades of digitally-derived projects, often produced simply for their novelty. The best work results when the architect has combined respect for the old with a skilled progressive command of the new. Material culture is portrayed as the physical confirmation and articulation of a culture in its relics and design. In the time that we comprehend the thought of material culture not just as having importance for investigations of the past. yet in addition getting a projective limit. we may now be at a critical defining moment.. As computation starts to significantly change our origination of the material, so in architecture this will defy the set up connection between the procedures of design and the physical fabrication of the constructed medium . Obviously, computation was brought into design & architecture the greater part a century back. furthermore, expanding digitization has since plagued all parts of the field . As though, it has remained emphatically impacted by the theoretical isolation of the procedures of design and making that has overwhelmed structural plan thinking since the Renaissance, and it is just now that creators are starting to deal with the computational void as never again disconnecting from the physical domain.


2007 ◽  
Vol 20 (4) ◽  
pp. 352-375 ◽  
Author(s):  
Elizabeth White Baker ◽  
Said S. Al‐Gahtani ◽  
Geoffrey S. Hubona

2022 ◽  
Author(s):  
Jasmine Amirzadegan ◽  
tunc.kayikcioglu not provided ◽  
hugh.rand not provided ◽  
Ruth E Timme ◽  
Maria Balkey

PURPOSE: Step-by-step instructions for checking sequence quality for SARS-CoV-2 wastewater samples using SSQuAWK: SARS - CoV - 2 Sequence Quality Assurance Workflow and Kontraption. The SSQuAWK workflow, implemented in a custom Galaxy instance, will produce quality assessments for raw reads (Illumina MiSeq paired-end fastq files). SCOPE: This protocol covers the following tasks: 1. Set up an account in GalaxyTrakr 2. Create a new history 3. Upload data 4. Execute the SSQuAWK workflow 5. Interpret the results Version history: V1: Basic protocol steps with screenshots V2: Addition of a detailed 12 minute video tutorial


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