997 resultados para Tintoretto, 1512-1594.


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The socially responsible investment (SRI) funds performances remain inconclusive. Hence, more studies need to be conducted to determine if SRI funds systematically underperform or outperform conventional funds. This paper has employed dynamic mean-variance model using shortage function approach to evaluate the performance of SRI and Environmentally friendly funds (EF). Unlike the traditional methods, this approach estimates fund performance considering both the return and risk at the same time. The empirical results show that SRI funds outperformed conventional funds in EU and US. In addition, the results of EU are among the top-performing categories. EF do not perform as well as SRI, but perform in manners equal or superior to conventional funds. These results show statistically significant in some cases.

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Aim A recent Monte Carlo based study has shown that it is possible to design a diode that measures small field output factors equivalent to that in water. This is accomplished by placing an appropriate sized air gap above the silicon chip (1) with experimental results subsequently confirming that a particular Monte Carlo design was accurate (2). The aim of this work was to test if a new correction-less diode could be designed using an entirely experimental methodology. Method: All measurements were performed on a Varian iX at a depth of 5 cm, SSD of 95 cm and field sizes of 5, 6, 8, 10, 20 and 30 mm. Firstly, the experimental transfer of kq,clin,kq,msr from a commonly used diode detector (IBA, stereotactic field diode (SFD)) to another diode detector (Sun Nuclear, unshielded diode, (EDGEe)) was tested. These results were compared to Monte Carlo calculated values of the EDGEe. Secondly, the air gap above the EDGEe silicon chip was optimised empirically. Nine different air gap “tops” were placed above the EDGEe (air depth = 0.3, 0.6, 0.9 mm; air width = 3.06, 4.59, 6.13 mm). The sensitivity of the EDGEe was plotted as a function of air gap thickness for the field sizes measured. Results: The transfer of kq,clin,kq,msr from the SFD to the EDGEe was correct to within the simulation and measurement uncertainties. The EDGEe detector can be made “correction-less” for field sizes of 5 and 6 mm, but was ∼2% from being “correction-less” at field sizes of 8 and 10 mm. Conclusion Different materials will perturb small fields in different ways. A detector is only “correction-less” if all these perturbations happen to cancel out. Designing a “correction-less” diode is a complicated process, thus it is reasonable to expect that Monte Carlo simulations should play an important role.

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Aim A new method of penumbral analysis is implemented which allows an unambiguous determination of field size and penumbra size and quality for small fields and other non-standard fields. Both source occlusion and lateral electronic disequilibrium will affect the size and shape of cross-axis profile penumbrae; each is examined in detail. Method A new method of penumbral analysis is implemented where the square of the derivative of the cross-axis profile is plotted. The resultant graph displays two peaks in the place of the two penumbrae. This allows a strong visualisation of the quality of a field penumbra, as well as a mathematically consistent method of determining field size (distance between the two peak’s maxima), and penumbra (full-widthtenth-maximum of peak). Cross-axis profiles were simulated in a water phantom at a depth of 5 cm using Monte Carlo modelling, for field sizes between 5 and 30 mm. The field size and penumbra size of each field was calculated using the method above, as well as traditional definitions set out in IEC976. The effect of source occlusion and lateral electronic disequilibrium on the penumbrae was isolated by repeating the simulations removing electron transport and using an electron spot size of 0 mm, respectively. Results All field sizes calculated using the traditional and proposed methods agreed within 0.2 mm. The penumbra size measured using the proposed method was systematically 1.8 mm larger than the traditional method at all field sizes. The size of the source had a larger effect on the size of the penumbra than did lateral electronic disequilibrium, particularly at very small field sizes. Conclusion Traditional methods of calculating field size and penumbra are proved to be mathematically adequate for small fields. However, the field size definition proposed in this study would be more robust amongst other nonstandard fields, such as flattening filter free. Source occlusion plays a bigger role than lateral electronic disequilibrium in small field penumbra size.

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Aim The assessment of treatment plans is an important component in the education of radiation therapists. The establishment of a grade for a plan is currently based on subjective assessment of a range of criteria. The automation of assessment could provide a number of advantages including faster feedback, reduced chance of human error, and simpler aggregation of past results. Method A collection of treatments planned by a cohort of 27 second year radiation therapy students were selected for quantitative evaluation. Treatment sites included the bladder, cervix, larynx, parotid and prostate, although only the larynx plans had been assessed in detail. The plans were designed with the Pinnacle system and exported using the DICOM framework. Assessment criteria included beam arrangement optimisation, volume contouring, target dose coverage and homogeneity, and organ-at-risk sparing. The in-house Treatment and Dose Assessor (TADA) software1 was evaluated for suitability in assisting with the quantitative assessment of these plans. Dose volume data were exported in per-student and per-structure data tables, along with beam complexity metrics, dose volume histograms, and reports on naming conventions. Results The treatment plans were exported and processed using TADA, with the processing of all 27 plans for each treatment site taking less than two minutes. Naming conventions were successfully checked against a reference protocol. Significant variations between student plans were found. Correlation with assessment feedback was established for the larynx plans. Conclusion The data generated could be used to inform the selection of future assessment criteria, monitor student development, and provide useful feedback to the students. The provision of objective, quantitative evaluations of plan quality would be a valuable addition to not only radiotherapy education programmes but also for staff development and potentially credentialing methods. New functionality within TADA developed for this work could be applied clinically to, for example, evaluate protocol compliance.

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IN MANY FACTORIES, the feed chute of the first mill is operated with a high chute level for the purpose of maximising the cane rate through the mill. There is a trend towards trying to control chute level within a small control range near the top of a chute that can result in rapid changes in cane feeding rate to maintain the chute level set point. This paper reviews the theory that predicts higher cane rate with higher chute level and discusses the main weakness in the theory that it does not consider the beneficial effect on capacity of cane falling from the top of the chute to the top surface of the cane mat. An extension to the chute theory model is described that predicts higher capacity with lower chute level because of the effect of the falling cane. The original model and this extended model are believed to be the upper and lower limits to the true effect. The paper reports an experiment that measured the real effect of chute level on capacity and finds that increasing chute level does lead to higher capacity but that the trend is only about one-third as strong as the original theory predicted. The paper questions whether the benefits of slightly greater capacity outweigh the costs of operating with the small control range near the top of the chute.

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Introduction: The plantar heel pad is a specialized fibroadipose tissue that attenuates and, in part, dissipates the impact energy associated with heel strike. Although near maximal deformation of the heel pad has been shown during running, in vivo measurement of the deformation and structural properties of the heel pad during walking remains largely unexplored. This study employed a fluoroscope, synchronized with a pressure platform, to obtain force–deformation data for the heel pad during walking. Methods: Dynamic lateral foot radiographs were acquired from 6 male and 10 female adults (age, 45 ± 10 yrs; height, 1.66 ± 0.10 m; and weight, 80.7 ± 10.8 kg), while walking barefoot at preferred speeds. The inferior aspect of the calcaneus was digitized and the sagittal thickness and deformation of the heel pad relative to the support surface calculated. Simultaneous measurement of the peak force beneath the heel was used to estimate the principal structural properties of the heel pad. Results: Transient loading profiles associated with walking induced rapidly changing deformation rates in the heel pad and resulted in irregular load–deformation curves. The initial stiffness (32 ± 11 N.mm-1) of the heel pad was an order of magnitude lower than its final stiffness (212 ± 125 N.mm-1) and on average, only 1.0 J of energy was dissipated by the heel pad with each step during walking. Peak deformation (10.3 mm) approached that predicted for the limit of pain tolerance (10.7 mm). Conclusion: These findings suggest the heel pad operates close to its pain threshold even at speeds encountered during barefoot walking and provides insight as to why barefoot runners may adopt ‘forefoot’ strike patterns that minimize heel loading.

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Dengue fever/dengue haemorrhagic fever (DF/DHF) appears to be emerging in Hanoi in recent years. A case-control study was performed to investigate risk factors for the development of DF/DHF in Hanoi. A total of 73 patients with DF/DHF and 73 control patients were included in the study. The risk factor analysis indicated that living in rented housing, living near uncovered sewers, and living in a house discharging sewage directly into to ponds were all significantly associated with DF/DHF. People living in rented houses were 2·2 times more at risk of DF/DHF than those living in their own homes [adjusted odds ratio (aOR) 2·2, 95% confidence interval (CI) 1·1–4·6]. People living in an unhygienic house, or in a house discharging sewage directly to the ponds were 3·4 times and 4·3 times, respectively, more likely to be associated with DF/DHF (aOR 3·4, 95% CI 1–11·7; aOR 4·3, 95% CI 1·1–16·9). These results contribute to the understanding of the dynamics of dengue transmission in Hanoi, which is needed to implement dengue prevention and control programmes effectively and efficiently.

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Aim: In 2013 QUT introduced the Medical Imaging Training Immersive Environment (MITIE) as a virtual reality (VR) platform that allowed students to practice general radiography. The system software has been expanded to now include C-Arm. The aim of this project was to investigate the use of this technology in the pedagogy of undergraduate medical imaging students who have limited to no experience in the use of the C-Arm clinically. Method: The Medical Imaging Training Immersive Environment (MITIE) application provides students with realistic and fully interactive 3D models of C-Arm equipment. As with VR initiatives in other health disciplines (1–2) the software mimics clinical practice as much as possible and uses 3D technology to enhance 3D spatial awareness and realism. The application allows students to set up and expose a virtual patient in a 3D environment as well as creating the resultant “image” for comparison with a gold standard. Automated feedback highlights ways for the student to improve their patient positioning, equipment setup or exposure factors. The students' equipment knowledge was tested using an on line assessment quiz and surveys provided information on the students' pre-clinical confidence scale, with post-clinical data comparisons. Ethical approval for the project was provided by the university ethics panel. Results: This study is currently under way and this paper will present analysis of initial student feedback relating to the perceived value of the application for confidence in a high risk environment (i.e. operating theatre) and related clinical skills development. Further in-depth evaluation is ongoing with full results to be presented. Conclusion: MITIE C-Arm has a development role to play in the pre-clinical skills training for Medical Radiation Science students. It will augment their theoretical understanding prior to their clinical experience. References 1. Bridge P, Appleyard R, Ward J, Phillips R, Beavis A. The development and evaluation of a virtual radiotherapy treatment machine using an immersive visualisation environment. Computers and Education 2007; 49(2): 481–494. 2. Gunn T, Berry C, Bridge P et al. 3D Virtual Radiography: Development and Initial Feedback. Paper presented at the 10th Annual Scientific Meeting of Medical Imaging and Radiation Therapy, March 2013 Hobart, Tasmania.

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Object detection is a fundamental task in many computer vision applications, therefore the importance of evaluating the quality of object detection is well acknowledged in this domain. This process gives insight into the capabilities of methods in handling environmental changes. In this paper, a new method for object detection is introduced that combines the Selective Search and EdgeBoxes. We tested these three methods under environmental variations. Our experiments demonstrate the outperformance of the combination method under illumination and view point variations.

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The object of this study is Jacopo Bassano (c. 1510 1592) as a fresco painter and the significance of frescoes in his late production. The research focuses on the only surviving cycle of frescoes of his later years in the Cartigliano parish church, bearing the date 1575. The other cycle studied here was painted for the 16th century parish church of Enego. It contained one of the most extensive fresco decorations executed by Jacopo Bassano together with his eldest son Francesco. However, nothing has survived of the fresco cycle and the ceiling paintings of the church, nor is any visual documentation of them left. Only the small altarpiece attributed to Jacopo Bassano and depicting Saints Justine, Sebastian, Anthony Abbott, and Roch (dated to c. 1555/1560) has been preserved. I have suggested that the frescoes of the Cartigliano parish church should be examined in the interpretational context of the spirituality of the post-Tridentine period. This period frames the historical context for the frescoes and functions as a basis for the iconographical interpretation that I have proposed. I have shown that the iconographic programme of the frescoes in the choir of the Cartigliano parish church has obvious points of contact with the Catholic doctrines reconfirmed by the Council of Trent (1545 1563). I also argue that the fresco cycle and the ceiling paintings of the Enego church should be placed in the same interpretational context as the frescoes of Cartigliano. I present a reconstruction of the frescoes in the choir attributed to Jacopo Bassano and of those on the walls of the nave attributed to his son Francesco Bassano. According to my reconstruction, the frescoes in the choir and nave walls formed a coherent cycle with a unitary iconographic programme which included the 28 paintings with Old Testament subjects in the nave ceiling. The reconstruction includes the dating and the iconography of the fresco programme and its interpretative basis. The reconstruction is based on visitation records and inventories from the 16th and 17th centuries as well as on the oldest relevant literature, namely the descriptions offered by Carlo Ridolfi (1648) and G. B. Verci (1775). I also consider the relationship of the large compositional sketches attributed to Jacopo Bassano and depicting Christological subjects to the lost frescoes in Enego. These studies have been executed with coloured chalks, and many of them are also dated 1568 or 1569 by the painter. I suggest in this study that these large studies in coloured chalks were preparatory drawings for the fresco cycle in Enego, depicting scenes from the life and suffering of Christ. All the subjects of the aforesaid drawings were included in the Enego cycle.

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Työ on tapaustutkimus turkulaisen arkkidiakonin ja tuomiorovastin Paavali Scheelin ja Danzigin porvarin Hans Chonnertin sekä tämän pojan Hans Chonnert nuoremman kaupankäynnistä ja kaupan organisaatiosta. Työn pääasiallisena lähdeaineistona on käytetty Paavali Scheelin kirjekokoelmaa vuosilta 1509–1516. Suomen keskiajan lähteiden joukossa ainutlaatuinen kirjekokoelma mahdollistaa henkilötasolle ulottuvan tarkastelun sekä kaupassa ja henkilöverkostossa ilmenevien muutosten seuraamisen. Kirjekokoelman ohella on käytetty laajasti muita Itämeren piirin editoituja aikalaislähteitä. Aineiston lähiluvulla on hahmoteltu Scheelin ja Chonnertin kauppaverkosto: kaupan kannalta keskeiset henkilösuhteet ja henkilösuhteiden merkitys kaupassa. Verkoston kannalta olennaista on henkilöiden erilaisten roolien erottelu sekä kauppiaan, laivurin, lähetin ja velallisen roolien merkitys kauppaverkostossa. Scheelin ja Chonnertin kauppakontaktit osuvat osittain samalle ajalle Itämerellä 1500-luvun alussa käytyjen sotien kanssa. Tanskan ja Ruotsin unionikiistat sekä Tanskan ja Lyypekin (hansan) väliset kauppakiistat johtivat 1500-luvun alussa monivuotisiin sotiin, joiden yhteisenä piirteenä oli kaapparitoiminta vastustajan rannikoilla ja Itämeren keskeisillä kauppareiteillä. Itämeren kaapparisota muodostaa Scheelin ja Chonnertin kauppaverkoston kontekstin vuosina 1509–1512. Kaapparisodan loppuminen vuonna 1512 mahdollistaa Scheelin ja Chonnertin kauppaverkoston sodan- ja rauhanajan organisaation ja toiminnan vertailun. Scheelin ja Chonnertin kauppaverkoston ytimen muodosti pieni kauppiaiden ydinjoukko, johon kuului Turussa sekä kirkonmiehiä että porvareita. Ydinjoukon toiminta perustui luottamukseen, luottoihin, henkilökohtaisiin ystävyyssuhteisiin ja tiiviiseen informaation vaihtoon kirjeitse tai lähettien välityksellä. Vaikka purjehdus oli kaupankäynnin elinehto, laivureiden rooli kauppaverkostossa oli toissijainen. Sodan loppuminen Itämerellä johti laivureiden täydelliseen vaihtumiseen vuosien 1512–1513 aikana. Kauppaverkoston ydinryhmä sen sijaan säilyi samana, ja sen yhteistoiminta tiivistyi. Laajemmassa kontekstissa tapaustutkimus johtaa kolmeen päätelmään: 1) Paavali Scheelin omissa nimissään käymä kauppa oli normaali osa Turun tuomiokapitulin toimintaa; 2) turkulaiset kirkonmiehet ja porvarit tekivät kaupan saralla pitkälle menevää yhteistyötä, ja heidän kauppaverkostonsa olivat kytköksissä toisiinsa; 3) tanskalaisten monivuotinen kaapparitoiminta ei estänyt kaupankäyntiä Turun ja Danzigin välillä.

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There are two major pests of sorghum in Australia, the sorghum midge, Stenodiplosis sorghicola (Coquillett), and the corn earworm, Helicoverpa armigera (Hübner). During the past 10 years the management of these pests has undergone a revolution, due principally to the development of sorghum hybrids with resistance to sorghum midge. Also contributing has been the adoption of a nucleopolyhedrovirus for the management of corn earworm. The practical application of these developments has led to a massive reduction in the use of synthetic insecticides for the management of major pests of sorghum in Australia. These changes have produced immediate economic, environmental and social benefits. Other flow-on benefits include providing flexibility in planting times, the maintenance of beneficial arthropods and utilisation of sorghum as a beneficial arthropod nursery, a reduction in midge populations and a reduction in insecticide resistance development in corn earworm. Future developments in sorghum pest management are discussed.

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The variation of the interdiffusion coefficient with the change in composition in the Nb-Mo system is determined in the temperature range of 1800 °C to 1900 °C. It was found that the activation energy has a minimum at around 45 at. pct Nb. The values of the pre-exponential factor and the activation energy for diffusion are compared with the data available in the literature. Further, the impurity diffusion coefficients of Nb in Mo and Mo in Nb are calculated.