840 resultados para external beam radiotherapy


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This paper applies the Multi-Harmonic Nonlinear Receptance Coupling Approach (MUHANORCA) (Ferreira 1998) to evaluate the frequency response characteristics of a beam which is clamped at one end and supported at the other end by a nonlinear cubic stiffness joint. In order to apply the substructure coupling technique, the problem was characterised by coupling a clamped linear beam with a nonlinear cubic stiffness joint. The experimental results were obtained by a sinusoidal excitation with a special force control algorithm where the level of the fundamental force is kept constant and the level of the harmonics is kept zero for all the frequencies measured.

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The interferometer for low resolution portable Fourier Transform middle infrared spectrometer was developed and studied experimentally. The final aim was a concept for a commercial prototype. Because of the portability, the interferometer should be compact sized and insensitive to the external temperature variations and mechanical vibrations. To minimise the size and manufacturing costs, Michelson interferometer based on plane mirrors and porch swing bearing was selected and no dynamic alignment system was applied. The driving motor was a linear voice coil actuator to avoid mechanical contact of the moving parts. The driving capability for low mirror driving velocities required by the photoacoustic detectors was studied. In total, four versions of such an interferometer were built and experimentally studied. The thermal stability during the external temperature variations and the alignment stability over the mirror travel were measured using the modulation depth of the wide diameter laser beam. Method for estimating the mirror tilt angle from the modulation depth was developed to take account the effect from the non-uniform intensity distribution of the laser beam. The spectrometer stability was finally studied also using the infrared radiation. The latest interferometer was assembled for the middle infrared spectrometer with spectral range from 750 cm−1 to 4500 cm−1. The interferometer size was (197 × 95 × 79) mm3 with the beam diameter of 25 mm. The alignment stability as the change of the tilt angle over the mirror travel of 3 mm was 5 μrad, which decreases the modulation depth only about 0.7 percent in infrared at 3000 cm−1. During the temperature raise, the modulation depth at 3000 cm−1 changed about 1 . . . 2 percentage units per Celsius over short term and even less than 0.2 percentage units per Celsius over the total temperature raise of 30 °C. The unapodised spectral resolution was 4 cm−1 limited by the aperture size. The best achieved signal to noise ratio was about 38 000:1 with commercially available DLaTGS detector. Although the vibration sensitivity requires still improving, the interferometer performed, as a whole, very well and could be further developed to conform all the requirements of the portable and stable spectrometer.

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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

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The aim of this three phase study was to develop quality of radiotherapy care by the e-Feedback knowledge of radiotherapy -intervention (e-Re-Know). In Phase I, the purpose was to describe the quality of radiotherapy care and its deficits experienced by cancer patients. Based on the deficits in patient education in Phase II, the purpose was to describe cancer patients’ e-knowledge expectations in radiotherapy. In Phase III, the purpose was to develop and evaluate the outcomes of the e-Re-Know among breast cancer patients. The ultimate aim was to develop radiotherapy care to support patients’ empowerment with patient e-education. In Phase I (2004-2005), the descriptive design was used, and 134 radiotherapy patients evaluated their experiences by Good Nursing Care Scale for Patients (GNCS-P) in the middle of RT period. In Phase II (2006-2008), the descriptive longitudinal design was used and 100 radiotherapy patients’ e-knowledge expectations of RT were evaluated using open-ended questionnaire developed for this study before commencing first RT, in the middle of the treatment, and concluding RT period. In Phase III, firstly (2009-2010), the e-Re-Know intervention, i.e. knowledge test and feedback, was developed in terms of empowering knowledge and implemented with e-feedback approach based on literature and expert reviews. Secondly (2011-2014), the randomized controlled study was used to evaluate the e-Re-Know. Breast cancer patients randomized to either the intervention group (n=65) receiving the e-Re-Know by e-mail before commencing first RT and standard education or the control group (n=63) receiving standard education. The data were collected before commencing first RT, concluding last RT and 3 months after last RT using RT Knowledge Test, Spielberger’s State Trait Inventory (STAI) and Functional Assessment of Cancer Therapy - Breast (FACT-B) –instruments. Data were analyzed using statistical methods and content analysis. The study showed radiotherapy patients experienced quality of care high. However, there were deficits in patient education. Furthermore, radiotherapy patients’ multidimensional e-knowledge expectations through Internet covered mainly bio-physiological and functional knowledge. Thus, the e-Re-Know was developed and evaluated. The study showed when breast cancer patients’ carried out the e-Re-Know their knowledge of side effects self-care was significantly increased and quality of life (QOL) significantly improved in line with decrease in anxiety from time before radiotherapy period to three months after. In addition, the e-Re-Know has potential to have positive effects on anxiety and QOL, regardless of patient characteristics or knowledge level. The results support the theory of empowering patient education suggesting that empowerment can be supported by confirming patients’ understanding of own knowledge level. In summary, the e-Feedback knowledge of radiotherapy (e-Re-Know) intervention can be recommended in development of quality of radiotherapy care experienced by breast cancer patients. Further research is needed to assess and develop patient-centred quality of care by patient education among cancer patients.

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The objective of this multicenter prospective study was to determine the clinical efficacy and toxicity of a polychemotherapeutic third generation regimen, VACOP-B, with or without radiotherapy as front-line therapy in aggressive localized non-Hodgkin's lymphoma. Ninety-three adult patients (47 males and 46 females, median age 45 years) with aggressive localized non-Hodgkin's lymphoma, 43 in stage I and 50 in stage II (non-bulky), were included in the study. Stage I patients received VACOP-B for 6 weeks plus involved field radiotherapy and stage II patients received 12 weeks VACOP-B plus involved field radiotherapy on residual masses. Eighty-six (92.5%) achieved complete remission and 4 (4.3%) partial remission. Three patients (3.2%) were primarily resistant. Ten-year probability of survival, progression-free survival and disease-free survival were 87.3, 79.9 and 83.9%, respectively. Eighty-four patients are surviving at a median observation time of 57 months (range: 6-126). Statistical analysis showed no difference between stages I and II in terms of response, ten-year probability of survival, progression-free survival or disease-free survival. Side effects and toxicity were negligible and were similar in the two patient groups. The results of this prospective study suggest that 6 weeks of VACOP-B treatment plus radiotherapy may be the therapy of choice in stage I aggressive non-Hodgkin's lymphoma. Twelve weeks of VACOP-B treatment with or without radiotherapy was shown to be effective and feasible for stage II. These observations need to be confirmed by a phase III study comparing first and third generation protocols in stage I-II aggressive non-Hodgkin's lymphoma.

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The cоncept оf sustainability-оriented innоvatiоn is recent and still under researched. The aim оf the Thesis is tо cоntribute tо the field and investigate hоw dо cоmpanies оperating in Pоland apply sustainability-оriented innоvatiоn (SОI) tо their cоre business activities, what are the differences between variоus business fоrms оf оrganizatiоn in terms оf SОI, and what type оf capabilities facilitate implementatiоn оf SОI. Given early stage оf empirical research оn sustainability-оriented innоvatiоn, an explоratоry-descriptive case study research strategy was taken applying qualitative methоds. 6 interviews with managers and CEОs оf 4 cоmpanies lоcated in Warsaw were cоnducted. In additiоn, twо academic expert panels with specialists frоm University оf Lоdz and Lappeenranta University оf Technоlоgy were carried оut in оrder tо suppоrt the findings. The study fоund оut that in case оf cоmpanies which purpоse is tо create pоsitive impact and develоp sustainable prоducts оr services by using innоvative apprоaches, SОI activities are embedded in оrganizatiоnal culture and prоcess sо that it is difficult tо differentiate between main business activities and SОI. In the оther twо cases SОI practices were in line with cоre business activities thus reflected the main оperatiоns and were determined as a part оf CSR strategy. Activities are industry specific and are cоntingent upоn resоurces and capabilities pоssessed. Amоng list оf success factоrs management suppоrt, CEО’s persоnal values, dedicated and mоtivated team, investments in research and develоpment, оrganizatiоnal culture, nоn-hierarchical cоmmunicatiоns channels, empоwerment оf emplоyees, prоvisiоn оf time and space fоr failures were identified as key оrganizatiоnal capabilities facilitating integratiоn оf SОI practices. Whereas market demand, NGОs’ pressure, regulatiоns enfоrced, access tо external funding, netwоrking and cооperating present external оr cоllabоrative capabilities suppоrting implementatiоn оf sustainability оriented innоvatiоn in cоmpanies. SОI takes a systemic apprоach that drives the transfоrmatiоn tо becоme sustainable business embedding and integrating sоcial, envirоnmental and ecоnоmic value creatiоn tоgether.

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Questions concerning perception are as old as the field of philosophy itself. Using the first-person perspective as a starting point and philosophical documents, the study examines the relationship between knowledge and perception. The problem is that of how one knows what one immediately perceives. The everyday belief that an object of perception is known to be a material object on grounds of perception is demonstrated as unreliable. It is possible that directly perceived sensible particulars are mind-internal images, shapes, sounds, touches, tastes and smells. According to the appearance/reality distinction, the world of perception is the apparent realm, not the real external world. However, the distinction does not necessarily refute the existence of the external world. We have a causal connection with the external world via mind-internal particulars, and therefore we have indirect knowledge about the external world through perceptual experience. The research especially concerns the reasons for George Berkeley’s claim that material things are mind-dependent ideas that really are perceived. The necessity of a perceiver’s own qualities for perceptual experience, such as mind, consciousness, and the brain, supports the causal theory of perception. Finally, it is asked why mind-internal entities are present when perceiving an object. Perception would not directly discern material objects without the presupposition of extra entities located between a perceiver and the external world. Nevertheless, the results show that perception is not sufficient to know what a perceptual object is, and that the existence of appearances is necessary to know that the external world is being perceived. However, the impossibility of matter does not follow from Berkeley’s theory. The main result of the research is that singular knowledge claims about the external world never refer directly and immediately to the objects of the external world. A perceiver’s own qualities affect how perceptual objects appear in a perceptual situation.

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Radiotherapy is one of the main approaches to cure prostate cancer, and its success depends on the accuracy of dose planning. A complicating factor is the presence of a metallic prosthesis in the femur and pelvis, which is becoming more common in elderly populations. The goal of this work was to perform dose measurements to check the accuracy of radiotherapy treatment planning under these complicated conditions. To accomplish this, a scale phantom of an adult pelvic region was used with alanine dosimeters inserted in the prostate region. This phantom was irradiated according to the planned treatment under the following three conditions: with two metallic prostheses in the region of the femur head, with only one prosthesis, and without any prostheses. The combined relative standard uncertainty of dose measurement by electron spin resonance (ESR)/alanine was 5.05%, whereas the combined relative standard uncertainty of the applied dose was 3.35%, resulting in a combined relative standard uncertainty of the whole process of 6.06%. The ESR dosimetry indicated that there was no difference (P>0.05, ANOVA) in dosage between the planned dose and treatments. The results are in the range of the planned dose, within the combined relative uncertainty, demonstrating that the treatment-planning system compensates for the effects caused by the presence of femur and hip metal prostheses.

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Laser beam welding (LBW) is applicable for a wide range of industrial sectors and has a history of fifty years. However, it is considered an unusual method with applications typically limited to welding of thin sheet metal. With a new generation of high power lasers there has been a renewed interest in thick section LBW (also known as keyhole laser welding). There was a growing body of publications during 2001-2011 that indicates an increasing interest in laser welding for many industrial applications, and in last ten years, an increasing number of studies have examined the ways to increase the efficiency of the process. Expanding the thickness range and efficiency of LBW makes the process a possibility for industrial applications dealing with thick metal welding: shipbuilding, offshore structures, pipelines, power plants and other industries. The advantages provided by LBW, such as high process speed, high productivity, and low heat input, may revolutionize these industries and significantly reduce the process costs. The research to date has focused on either increasing the efficiency via optimizing process parameters, or on the process fundamentals, rather than on process and workpiece modifications. The argument of this thesis is that the efficiency of the laser beam process can be increased in a straightforward way in the workshop conditions. Throughout this dissertation, the term “efficiency” is used to refer to welding process efficiency, specifically, an increase in efficiency refers an increase in weld’s penetration depth without increasing laser power level or decreasing welding speed. These methods are: modifications of the workpiece – edge surface roughness and air gap between the joining plates; modification of the ambient conditions – local reduction of the pressure in the welding zone; modification of the welding process – preheating of the welding zone. Approaches to improve the efficiency are analyzed and compared both separately and combined. These experimentally proven methods confirm previous findings and contribute additional evidence which expand the opportunities for laser beam welding applications. The focus of this research was primarily on the effects of edge surface roughness preparation and pre-set air gap between the plates on weld quality and penetration depth. To date, there has been no reliable evidence that such modifications of the workpiece give a positive effect on the welding efficiency. Other methods were tested in combination with the two methods mentioned above. The most promising - combining with reduced pressure method - resulted in at least 100% increase in efficiency. The results of this thesis support the idea that joining those methods in one modified process will provide the modern engineering with a sufficient tool for many novel applications with potential benefits to a range of industries.

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The objective of this work was to develop a recommendation for the chemical peeling of pequi fruit and characterize the flour obtained from the external mesocarp of "Pequizeiro", pequi tree (Caryocar brasiliense Camb.). The technology applied to obtain the external mesocarp pequi flour included the epicarp removal with NaOH solution. The Response Surface Method was used to optimize the chemical peeling process by applying the Central Composite Rotatable Design, with eleven trials including three replicates at the central point, varying the NaOH aqueous solution concentration and fruit immersion time. The mass loss was evaluated through the analysis of variance and using bi and three dimensional graphs. The chemical characteristics of the external mesocarp pequi flour evaluated were: moisture content, ashes, proteins, lipids, total carbohydrates, dietary fiber, and some minerals. The best combination for an efficient removal of the fruit peel with the lowest mass loss was reached with 7.05 minutes of immersion in a 5.08 g.L-1 NaOH aqueous solution. This study indicated that the external mesocarp pequi flour is a food source rich in dietary fiber, carbohydrates, ashes, magnesium, calcium, manganese, and copper, but it is poor in lipids, zinc, and iron.

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The objective of this study was to evaluate the hygienic-sanitary conditions of hospital nutrition and dietary services using external and internal auditors. Eleven hospitals were evaluated for their nutrition and dietary services using an evaluation checklist based on food safety requirements in the current legislation. The checklist was applied by an internal auditor (a technical supervisor) and an external auditor (a professional with experience in food services) between August and October 2011. According to the number of items on the evaluation checklist that were considered adequate, the hospital facilities were ranked as excellent, good, regular, bad, or very bad. The results obtained by the auditors were compared. According to these results, it can be said that most of the hospital nutrition and dietary services were rated as good for overall quality by the internal auditor, while the external auditor classified them as Regular. There was a clear difference between the evaluations of the auditors, both in terms of the number of items considered adequate and the overall requirements' average score. It can be concluded that hospital nutrition and dietary services should meet safety requirements in order to provide food. These facilities should have external audits conducted as a way to prevent routine problems from being perpetuated.

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More than one decade after the external debt restructuring (the Brady Plan), a great amount of literature has been published concerning the balance sheet factors in developing countries. The staff of international multilateral institutions joined with reputable academics in this great controversy. The external debt problem of the developing countries is back and once more reflections on its cause and on policy recommendations are analytically distinct. Our main task is to reflect on the recent external debt dynamics and assess how this debt has evolved. Our findings indicate that the susceptibility of some developing countries to default is associated with global imbalance, that is, the way they borrow.

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The present paper examines the Brazilian experience from the 'Economic Miracle' to the 'Lost Decade'. Its aim is to advance an alternative measurement of the flows of extraordinary wealth (i.e. ground-rent and net external credit) available for appropriation in the Brazilian economy and to asses their relevance in sustaining the process of accumulation of industrial capital. That is done in order to provide further and more accurate evidence to the claim that the evolution of the Brazilian process of capital accumulation has been extremely dependent on the evolution of those masses of extraordinary wealth.

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The purpose of this study is to explore how scenarios can be exploited in strategic assessment of the external business environment. One of the key challenges for managers worldwide is to adapt their businesses to the ever-changing business environment. As the companies’ external business environment is constantly presenting new opportunities and threats, it is extremely important that companies continuously monitor the possible changes happening around it. As the speed of change rises, assessing the future has become more and more vital. The study was conducted as an exploratory research and the research strategy was influenced by scenario planning and case study strategy. The study examined the European pet food sector from the future point of view. Qualitative study was chosen as research approach and empirical data was collected primarily by seven expert interviews. The secondary data about the sector was applied as complementary empirical data. In the theoretical part of the research it was discovered that nowadays, traditional analysis frameworks are ill-suited for strategic assessment of the external business environment. This is why a self-created combination framework for analysis was employed both as study’s theoretical framework and analysis technique. Furthermore, the framework formed the base for interview questions. Both in theoretical and the empirical part of the study it was found that today, in strategic assessment of the external business environment, besides setting focus on the current situation, it is important to concentrate also on the future. The traditional analysis frameworks offer a good starting point for collecting relevant data but they do not encourage conducting a deeper analysis. By adding characteristics from scenario planning to these more traditional tools, a new analysis framework was created, which ensured the more comprehensive analysis. By understanding the interconnections between discovered phenomena and changes, and by recognizing uncertainties, the user is helped to reflect the environment more profoundly. The contributions of the study are both theoretical and managerial. A new analysis framework strives to answer to the current needs for strategic assessment of external business environment and the framework was tested in the context of European pet food sector. When it comes to managerial contributions, the importance lies in understanding the future. Managers must take future into account and understand that future includes various possibilities which all must be reflected