89 research outputs found

    Layout Optimization of a repair facility using discrete event simulation

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    Technological advancements in the field of simulation have enabled production managers to model and simulate their facilities under various scenarios, in order to optimize system performance. In particular the reconfiguration of factory layouts can be time consuming and expensive; Discrete Event Simulation (DES) can be used to model and assess various scenarios to assist production managers with layout planning. Significant benefits can be achieved through the use of DES for factory layout optimization including: decreased lead times, reduced manufacturing costs, efficient materials handling and increased profit. This paper presents the development of a DES model in WITNESS for the analysis and factory layout optimization of a repair facility. The aim of the model is to allow decision makers to assess various layouts and configurations with a view to optimize production. The model has been built with a link to an Excel spreadsheet to enable data input and the visualization of Key Performance Indicators (KPIs). Specific functions have been built into the simulation model to set and save new layouts within Excel to facilitate layout optimization. The model will be used to optimize the factory configuration

    A 3D immersive discrete event simulator for enabling prototyping of factory layouts

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    There is an increasing need to eliminate wasted time and money during factory layout design and subsequent construction. It is presently difficult for engineers to foresee if a certain layout is optimal for work and material flows. By exploiting modelling, simulation and visualisation techniques, this paper presents a tool concept called immersive WITNESS that combines the modelling strengths of Discrete Event Simulation (DES) with the 3D visualisation strengths of recent 3D low cost gaming technology to enable decision makers make informed design choices for future factories layouts. The tool enables engineers to receive immediate feedback on their design choices. Our results show that this tool has the potential to reduce rework as well as the associated costs of making physical prototypes

    Simulations of imperfect refractive index matching in scanning laser optical tomography and a method for correction

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    Since additive manufacturing has become increasingly popular in prototyping, printed optics are also beginning to enter the market. Novel characterization methods for printed optics are needed because traditional, destructive methods often do not work on these optics. The scope of investigation is also different for additively manufactured optics. Homogeneity of subtractive manufactured optics such as glass lenses is usually granted but for printed optics the interfaces in-between layers can cause absorption, scattering or refraction. Functionalized optics can also have characteristics such as fluorescence that cannot be tested with traditional methods. The presented work tries to fill the void for this particular challenge by studying two non-destructive methods for optical characterization of such components and expanding their use by clever combination. In Scanning Laser Optical Tomography (SLOT), a needle-like beam is formed and focused into the sample. The sample is scanned to form projection images and rotated to allow for reconstruction, which yields volumetric data about scattering, transmission and fluorescence of sample structures. Simulated SLOT measurements with imperfect Refractive Index (RI) matching of sample and medium are presented. A method to correct distorted measurements is presented and evaluated. The simulations imply that a measurement with a RI mismatch of up to 0.1 can still yield reasonable results. Copyright 2023 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited

    The MATISSE study: a randomised trial of group art therapy for people with schizophrenia.

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    RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.BACKGROUND: Art Therapy has been promoted as a means of helping people who may find it difficult to express themselves verbally engage in psychological treatment. Group Art Therapy has been widely used as an adjunctive treatment for people with schizophrenia but there have been few attempts to examine its effects and cost effectiveness has not been examined. The MATISSE study aims to evaluate the clinical and cost effectiveness of group Art Therapy for people with schizophrenia. METHOD/DESIGN: The MATISSE study is a three-arm, parallel group, pragmatic, randomised, controlled trial of referral to group Art Therapy plus standard care, referral to an attention control 'activity' group plus standard care, or standard care alone. Study participants were recruited from inpatient and community-based mental health and social care services at four centres in England and Northern Ireland. Participants were aged over 18 years with a clinical diagnosis of schizophrenia, confirmed by an examination of case notes using operationalised criteria. Participants were then randomised via an independent and remote telephone randomisation service using permuted stacked blocks, stratified by site. Art Therapy and activity groups were made available to participants once a week for up to 12 months. Outcome measures were assessed by researchers masked to allocation status at 12 and 24 months after randomisation. Participants and care givers were aware which arm of the trial participants were allocated to. The primary outcomes for the study are global functioning (measured using the Global Assessment of Functioning scale) and mental health symptoms (measured using the Positive and Negative Syndrome Scale) assessed at 24 months. Secondary outcomes were assessed at 12 and 24 months and comprise levels of group attendance, social function, satisfaction with care, mental wellbeing, and costs. DISCUSSION: We believe that this is the first large scale pragmatic trial of Art Therapy for people with schizophrenia. TRIAL REGISTRATION: Current Controlled Trials ISRCTN46150447.Published versio

    ESTS guidelines for preoperative lymph node staging for non-small cell lung cancer

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    Accurate preoperative staging and restaging of mediastinal lymph nodes in patients with non-small cell lung cancer (NSCLC) is of paramount importance. It will guide choices of treatment and determine prognosis and outcome. Over the last years, different techniques have become available. They vary in accuracy and procedure-related morbidity. The Council of the ESTS initiated a workshop on preoperative mediastinal lymph node staging. This resulted in guidelines for primary staging and restaging. For primary staging, mediastinoscopy remains the gold standard for the superior mediastinal lymph nodes. Invasive procedures can be omitted in patients with peripheral tumors and negative mediastinal positron emission tomography (PET) images. However, in case of central tumors, PET hilar N1 disease, low fluorodeoxyglucose uptake of the primary tumor and LNs≥16mm on CT scan, invasive staging remains indicated. PET positive mediastinal findings should always be cyto-histologically confirmed. Transbronchial needle aspiration (TBNA), ultrasound-guided bronchoscopy with fine needle aspiration (EBUS-FNA) and endoscopic esophageal ultrasound-guided fine needle aspiration (EUS-FNA) are new techniques that provide cyto-histological diagnosis and are minimally invasive. Their specificity is high but the negative predictive value is low. Because of this, if they yield negative results, an invasive surgical technique is indicated. However, if fine needle aspiration is positive, this result may be valid as proof for N2 or N3 disease. For restaging, invasive techniques providing cyto-histological information are advisable despite the encouraging results supported with the use of PET/CT imaging. Both endoscopic techniques and surgical procedures are available. If they yield a positive result, non-surgical treatment is indicated in most patient

    Cytotoxicity and anti-Sporothrix brasiliensis activity of the Origanum majorana Linn. oil

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    The study aimed to evaluate the anti-Sporothrix sp. activity of the essential oil of Origanummajorana Linn. (marjoram), its chemical analysis, and its cytotoxic activity. A total of 18fungal isolates of Sporothrix brasiliensis (n: 17) from humans, dogs and cats, and a standardstrain of Sporothrix schenckii (n: 1) were tested using the broth microdilution technique (Clin-ical and Laboratory Standard Institute – CLSI M27-A3) and the results were expressed inminimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC). TheMIC50and MIC90of itraconazole against S. brasiliensis were 2 g/mL and 8 g/mL, respectively,and the MFC50and MFC90were 2 g/mL and >16 g/mL, respectively, with three S. brasilien-sis isolates resistant to antifungal. S. schenckii was sensitive at MIC of 1 g/mL and MFC of8 g/mL. For the oil of O. majorana L., all isolates were susceptible to MIC of ≤2.25–9 mg/mLand MFC of ≤2.25–18 mg/mL. The MIC50and MIC90were ≤2.25 mg/mL and 4.5 mg/mL, respec-tively, and the MFC50/90values were twice more than the MIC. Twenty-two compounds wereidentified by gas chromatography with a flame ionization detector (CG-FID) and 1,8-cineoleand 4-terpineol were the majority. Through the colorimetric (MTT) assay, the toxicity wasobserved in 70–80% of VERO cells between 0.078 and 5 mg/mL. For the first time, the studydemonstrated the satisfactory in vitro anti-Sporothrix sp. activity of marjoram oil and furtherstudies are needed to ensure its safe and effective use

    Análises químicas e citotóxicas de três variedades de própolis brasileiras (própolis verde, própolis jataí e própolis marrom) e sua atividade in vitro anti-Sporothrix brasiliensis

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    In this study, we described the antifungal activity of three Brazilian propolis extracts: brown, green and from jataí bees against Sporothrix brasiliensis. The extracts were obtained from ethanolic extraction and their chemical composition was determined by high-performance liquid chromatography coupled to mass spectrometry. The cellular toxicity was measured in MDBK (Madin-Darby Bovine Kidney) cells and quantified by the MTT assay (3- (4,5 dimethylthiazol-2yl -2,5-diphenyl-2H bromine tetrazolato). For antifungal activity, the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were determined by broth microdilution. The results showed that cell toxicity was not observed at lower concentrations (0.097 to 0.39μg/ml) for all extracts in comparison to cell control. Among the chemical compounds identified, caffeic acid, p-coumaric acid, chlorogenic acid, ferulic acid and rutin were quantified. In antifungal activity, green and jataí did not exhibit activity against the isolates (MIC and MFC greater than 0.78mg/ml). However, all isolates of S. brasiliensis were sensitive to brown propolis (MIC of 0.09 to 0.78mg/ml), including the standard strain (P<0.001). Among the Brazilian propolis studied, the brown propolis showed activity against the S. brasiliensis isolates and more studies should be undertaken in order to evaluate its promising use in the treatment of sporotrichosis.Neste estudo, descreveu-se a atividade antifúngica de três extratos de própolis brasileiras: marrom, verde e de abelhas jataí (Tetragonisca angustula), contra Sporothrix brasiliensis. Os extratos foram obtidos de extração etanólica, e a sua composição química foi determinada por cromatografia líquida de alta eficiência, acoplada à espectrometria de massa. A toxicidade celular foi medida em células MDBK (Madin-Darby Bovine Kidney), avaliada por observação microscópica e quantificada pelo ensaio MTT (3- (4,5-dimetiltiazol-2-ilo -2,5-difenil-2H bromo tetrazolato). Para a atividade antifúngica, determinou-se a concentração inibitória mínima (CIM) e a concentração fungicida mínima (CFM) por meio de microdiluição em caldo. Os resultados mostraram que a toxicidade celular não foi observada em concentrações menores (0,097 a 0,39μg/ml). Entre os compostos químicos identificados, foram quantificados o ácido cafeico, ácido p-cumárico, ácido clorogênico, ácido ferúlico e a rutina. Na atividade antifúngica, as própolis verde e jataí não apresentaram atividade contra os isolados (CIM e CFM maior que 0,78mg/ml), porém todos os isolados de S. brasiliensis foram sensíveis à própolis marrom (CIM de 0,09 a 0,78mg/ml), incluindo a cepa padrão (P<0,001). Entre as própolis brasileiras estudadas, a marrom mostrou atividade contra S. brasiliensis, e mais estudos devem ser realizados para avaliar seu uso promissor no tratamento da esporotricose

    Ruralization of students’ horizons: insights into Australian health professional students’ rural and remote placements

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    This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php).Introduction: Health workforce shortages have driven the Australian and other Western governments to invest in engaging more health professional students in rural and remote placements. The aim of this qualitative study was to provide an understanding of the lived experiences of students undertaking placements in various nonmetropolitan locations across Australia. In addition to providing their suggestions to improve rural placements, the study provides insight into factors contributing to positive and negative experiences that influence students’ future rural practice intentions. Methods: Responses to open-ended survey questions from 3,204 students from multiple health professions and universities were analyzed using two independent methods applied concurrently: manual thematic analysis and computerized content analysis using Leximancer software. Results: The core concept identified from the thematic analysis was “ruralization of students’ horizons,” a construct representing the importance of preparing health professional students for practice in nonmetropolitan locations. Ruralization embodies three interrelated themes, “preparation and support,” “rural or remote health experience,” and “rural lifestyle and socialization,” each of which includes multiple subthemes. From the content analysis, factors that promoted students’ rural practice intentions were having a “positive” practice experience, interactions with “supportive staff,” and interactions with the “community” in general. It was apparent that “difficulties,” eg, with “accommodation,” “Internet” access, “transport,” and “financial” support, negatively impacted students’ placement experience and rural practice intentions. Conclusions: The study findings have policy and practice implications for continuing to support students undertaking regional, rural, and remote placements and preparing them for future practice in nonmetropolitan locations. This study may, therefore, further inform ongoing strategies for improving rural placement experiences and enhancing rural health workforce recruitment, retention, and capacity building
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