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The personal in the professional : A Q-methodological study of the students’ subjective experience of how Experts in Teamwork facilitates the development of personal competenceDahl, Lene Røsok January 2012 (has links)
The purpose of this study has been to explore students’ subjective experience of learning and development in Experts in Teamwork (EiT), with a focus on personal competence. The basis for the study has been the question of research; How do students experience Experts in Teamwork facilitating the development of personal competence? This research is a Q-methodological study, where 36 participants have conducted a Q-sort. This means that they did a sort of 36 statements on an array from most agree (+5) to most disagree (-5), in a qu asi-normal distribution form. The statements were obtained from a research design based on Fisher ’s balanced block design. The participants Q-sorts were the basis for the factor analysis. The factor analysis of the data set, conducted by PQ-method-2.11, gave a four-factor solution founded on statistical and theoretical criteria. The different factors represent the most prominent point of views that were present amongst the participants. The different factors were; Factor 1: Personal development, feedback and group experiences are valuable to me. Factor 2: I trust the system to facilitate my learning trough theory-based learning. Factor 3: I want feedback and group work, but I don’t trust the system . Factor 4: Theory-based learning is what I prefer. Group work is scary . In the thesis these findings are discussed in relation to the theoretical frames; personal competence, experiential learning, mindset and selfunderstanding.The aspects that are highlighted are what I have found to be most prominent and that could contribute to give a holistic picture of the data set.
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Estudio y realización del control directo del par (DTC) para accionamientos de motores de inducción con inversores de diferentes topologiasMoustafa Azab, Mohamed Ahmed 06 September 2002 (has links)
El objetivo principal de la tesis es la aplicación del método de control directo del par para un motor de inducción utilizando inversores de diferentes estructuras que parecen ofrecer algunas ventajas, bajo ciertas condiciones, y que aún no han sido utilizados para el desarrollo de esta técnica de control.La idea y el tema de la tesis surgieron de la gran importancia del método control directo del par (DTC), que últimamente se planteó como estrategia alternativa del control vectorial debido a ciertas ventajas frente a este último. Por este motivo, y animados por el éxito logrado por el DTC, se quiere contribuir a un aumento del mismo utilizando varias topologías de inversores que amplíen o extiendan el área de aplicación de los accionamientos basados en el mismo en un rango que vaya desde bajas potencias hasta las potencias medianas. Aunque los objetivos principales de aplicar el DTC son obtener un accionamiento de comportamiento dinámico alto y buen funcionamiento durante el régimen estático, no obstante los requisitos de funcionamiento en el rango de las bajas potencias no son los mismos que aquellos de potencias medianas. En el rango de las bajas potencias, el coste total del conjunto del accionamiento (inversor - motor - circuitos de control) es un factor muy importante. Especialmente con las normas europeas que obligan a los fabricantes de inversores a mejorar la utilización de la red por ejemplo, limitando la tasa de distorsión armónica, y mejorando el factor de potencia, con lo cual se sustituyen el rectificador pasivo (diodos) por un rectificador activo (transistores), lo que aumenta el coste del accionamiento. Evidentemente, cualquier ahorro en el coste del inversor y los sensores permitirá la aplicación del DTC en gran escala. Por tanto, se ha elegido un inversor de cuatro interruptores (B4) que permite disminuir el coste del inversor y su circuito de control. Reduciendo también el número de sensores utilizados en el sistema. Esta técnica es nueva para este tipo de inversor, ya que el DTC nunca se había realizado basado en este esquema de inversor. Los estudios realizados en esta tesis mediante la simulación y sus validaciones experimentales han probado el buen comportamiento dinámico y estático del accionamiento.De otro parte, en el rango de potencia mediana (10 kW-100 kW) la aplicación del DTC esta limitada por la frecuencia de conmutación. La exigencia de una frecuencia de conmutación elevada hace aumentar las pérdidas de conmutación a través los interruptores del inversor. Los problemas generados por la conmutación rígida impiden subir la frecuencia de conmutación por encima de unos pocos cientos de hertz. Por ello, si el algoritmo del DTC se aplica teniendo en cuenta la limitación de la frecuencia de conmutación a estos pequeños valores, su comportamiento será bastante malo generando una distorsión en las formas de las ondas del par y del flujo, lo que a su vez se refleja en la velocidad y en las corrientes del motor. Para evitar estos problemas sería más conveniente utilizar un inversor resonante, pero también éste tiene algunos inconvenientes. En la tesis, se propone utilizar un inversor de tipo cuasi-resonante que tiene las ventajas de inversor resonante y las ventajas del inversor de conmutación dura. En tal caso, se conmutan los interruptores bajo la condición de cero tensión (ZVS) bajando al mínimo las pérdidas de conmutación lo que finalmente permite aumentar la frecuencia de conmutación hasta valores elevados del orden de 10 kHz. Además, la utilización de este tipo de inversor ofrece algunas ventajas como:- Limitar la dv/dt de la tensión que alimenta el motor, por tanto las corrientes de fugas parásitas se disminuyen, reduciendo la degradación o el envejecimiento de los aislantes de los devanados y de los cojinetes de la máquina, prolongando su vida útil.- Bajar el nivel de las interferencias electromagnéticas.- Reducir el tamaño de los radiadores de calor necesarios.Se ha diseñado y construido un inversor cuasi-resonante con los correspondientes circuitos de control para aplicar el DTC a los accionamientos de baja potencia. Además, se han desarrollado dos circuitos de resonancia. Los resultados obtenidos por simulación y los ensayos experimentales han probado el buen comportamiento de estos circuitos. En cuanto a la escritura de la tesis, esta estructurada en los ocho capítulos siguientes:Capítulo 1: Presenta el estado del arte relacionado al tema de la tesis.Capítulo 2: Estudio introductorio en el que se presenta el control directo del par mostrando sus respectivas, ventajas e inconvenientes. Capítulo 3: Se hace un repaso de las estrategias de control utilizadas en el caso de un inversor de cuatro interruptores, empezando con las estrategias básicas hasta llegar a la estrategia del DTC propuesta en esta tesis. Además, se muestran los resultados de las simulaciones con las diferentes estrategias de control.Capítulo 4: Se explica el funcionamiento del inversor cuasi-resonante, mediante un ejemplo de circuito de resonancia. Además se plantea otro circuito que se ha modificado para mejorar la respuesta y el funcionamiento del inversor. También, se presenta el sistema del DTC basado en este tipo de inversor. Capítulo 5: Se estudia el efecto del cambio de la resistencia del estator sobre el comportamiento del DTC. Además, se presentan algunos métodos para estimar el valor actual de la resistencia del estator durante el arranque y también durante el funcionamiento en régimen permanente.Capítulo 6: Se muestran los resultados experimentales obtenidos del desarrollo de los sistemas propuestos bajo varias condiciones de funcionamiento.Capítulo 7: Se presentan y discuten las conclusiones, y se proponen trabajos a realizar en el futuro.Capítulo 8: Incluye la bibliografía.
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A mixed method evaluation of the subjective well–being of first–year tertiary students during orientation / Johannes Hendrikus de KockDe Kock, Johannes Hendrikus January 2010 (has links)
The aim of orientation programs at tertiary academic institutions is to introduce newcomers
to the attitudinal and behavioral standards of their new academic and social situation, and
these programs usually have a formal and an informal component. Formal orientation is
officially developed and monitored by the university. Informal orientation is associated with
socially orientated initiation or hazing activities administered by senior students in the
seclusion of hostels and are often not monitored by the university, resulting in human rights
violations such as racial discrimination, physical abuse and psychological bullying. Because
both components of orientation take place during the same time frame and in the same
broader context, orientation programs as a whole have been receiving negative attention and
criticism in the media. Research has, however, also uncovered many positive elements in
orientation programs - in both the formal and informal components. Literature suggests that
universities put in place a high quality formal and informal orientation program to ensure the
well–being of first–year students.
Well–being is regarded as the subjective appraisals that people make about the quality of their
lives based on their experiences, relationships, feelings and overall functioning in life. Two
approaches towards subjective well–being are identified: the first is the hedonic approach,
focusing on emotional well–being (EWB) and is equated to positive feelings, subjective
happiness and satisfaction with life; the second is the eudaimonic approach, focusing on psychological well–being (PWB) and social well–being (SWB) which not only conceptualizes
well–being in terms of meaning and purpose, but also as positive functioning in life on
personal and social levels. The aim of this study was to determine the shifts in well–being of
first–year students during an orientation program (with both the formal and informal
components included) at a tertiary institution and to explore the experiences associated with
these shifts.
A sequential mixed method research design was used where quantitative and qualitative
research approaches were combined to provide an in–depth understanding of the
phenomenon. A convenience sample of first–year hostel residing students (mean age=19
years) was used for the quantitative study. Students completed the Mental Health Continuum
Short Form (MHC–SF) and the Satisfaction With Life Scale (SWLS) before (n=102), during
(n=371) and after (n=358) the orientation program. Twenty–one demographically
representative first–year hostel residing students (mean age=18.5 years) were purposive
selected to participate in the qualitative study consisting of a focus group discussion and
semi–structured in–depth individual interviews which took place after the programs’
completion.
The quantitative results indicated that first–year students’ well–being remained unchanged
before, during and after orientation in all facets except in SWB. First–year students’ SWB
increased practically significantly over the course of the orientation program. The qualitative
findings suggested that first–year students’ well–being fluctuated from high before the
orientation program to low during the program’s initial phase to high again after the
program’s completion. Experiences associated with SWB were perceived to be the central
experience associated with an increase in well–being. Recommendations are made regarding the promotion of the social and personal well–being of first–year students during an
orientation program. / Thesis (M.A. (Clinical Psychology))--North-West University, Potchefstroom Campus, 2011.
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A mixed method evaluation of the subjective well–being of first–year tertiary students during orientation / Johannes Hendrikus de KockDe Kock, Johannes Hendrikus January 2010 (has links)
The aim of orientation programs at tertiary academic institutions is to introduce newcomers
to the attitudinal and behavioral standards of their new academic and social situation, and
these programs usually have a formal and an informal component. Formal orientation is
officially developed and monitored by the university. Informal orientation is associated with
socially orientated initiation or hazing activities administered by senior students in the
seclusion of hostels and are often not monitored by the university, resulting in human rights
violations such as racial discrimination, physical abuse and psychological bullying. Because
both components of orientation take place during the same time frame and in the same
broader context, orientation programs as a whole have been receiving negative attention and
criticism in the media. Research has, however, also uncovered many positive elements in
orientation programs - in both the formal and informal components. Literature suggests that
universities put in place a high quality formal and informal orientation program to ensure the
well–being of first–year students.
Well–being is regarded as the subjective appraisals that people make about the quality of their
lives based on their experiences, relationships, feelings and overall functioning in life. Two
approaches towards subjective well–being are identified: the first is the hedonic approach,
focusing on emotional well–being (EWB) and is equated to positive feelings, subjective
happiness and satisfaction with life; the second is the eudaimonic approach, focusing on psychological well–being (PWB) and social well–being (SWB) which not only conceptualizes
well–being in terms of meaning and purpose, but also as positive functioning in life on
personal and social levels. The aim of this study was to determine the shifts in well–being of
first–year students during an orientation program (with both the formal and informal
components included) at a tertiary institution and to explore the experiences associated with
these shifts.
A sequential mixed method research design was used where quantitative and qualitative
research approaches were combined to provide an in–depth understanding of the
phenomenon. A convenience sample of first–year hostel residing students (mean age=19
years) was used for the quantitative study. Students completed the Mental Health Continuum
Short Form (MHC–SF) and the Satisfaction With Life Scale (SWLS) before (n=102), during
(n=371) and after (n=358) the orientation program. Twenty–one demographically
representative first–year hostel residing students (mean age=18.5 years) were purposive
selected to participate in the qualitative study consisting of a focus group discussion and
semi–structured in–depth individual interviews which took place after the programs’
completion.
The quantitative results indicated that first–year students’ well–being remained unchanged
before, during and after orientation in all facets except in SWB. First–year students’ SWB
increased practically significantly over the course of the orientation program. The qualitative
findings suggested that first–year students’ well–being fluctuated from high before the
orientation program to low during the program’s initial phase to high again after the
program’s completion. Experiences associated with SWB were perceived to be the central
experience associated with an increase in well–being. Recommendations are made regarding the promotion of the social and personal well–being of first–year students during an
orientation program. / Thesis (M.A. (Clinical Psychology))--North-West University, Potchefstroom Campus, 2011.
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Die Morfologie van die vroulike strobilus en embriologie van die genus Podocarpus L'Herit. ex Pers. in Suid-AfrikaSchoonraad, Elzabe January 1977 (has links)
No abstract available. / Thesis (PhD)--University of Pretoria, 1977. / gm2014 / Plant Science / unrestricted
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Razvoj matematičkog modela trajanja glasova u automatskoj sintezi govora na srpskom jeziku / The Development of Phone Duration Model in Speech Synthesis in theSerbian LanguageSovilj-Nikić Sandra 10 July 2014 (has links)
<p>U okviru ove disertacije razvijeno je više različitih modela trajanja glasova u srpskom jeziku primenom odgovarajućih metoda automatskog učenja. Izvršena je objektivna evaluacija razvijenih modela i njihovo međusobno poređenje na osnovu kvantitativnih pokazatelja kao što su RMSE(engl. root-mean-squared error), MAE (engl. mean absolute error) i CC (engl. correlation coefficient). Takođe je izvršeno poređenje modela za srpski jezik sa performansama modela razvijenih za druge jezike, pri čemu je uočeno da su performanse modela razvijenih u ovoj disertaciji uporedljive ili čak prevazilaze performanse modela koji su razvijeni za druge jezike.</p> / <p>In this dissertation several different phone duration models of the Serbain<br />language using appropriate machine learning algorithms were developed.<br />The objective evaluation of the models obtained and their mutual comparison<br />based on quantitative measures such as RMSE (root-mean-squared error),<br />MAE (mean absolute error) and CC (correlation coefficient) were performed.<br />The comparison of the models developed for the Serbian language with the<br />performances of the models developed for other languages is also carried<br />out. It was observed that the performances of the models developed in this<br />dissertation are comparable or even outperform the performances of the<br />models that have been developed for other languages.</p>
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Problem svesti u filozofiji duha i psihoterapijiHuber Izabela 30 June 2016 (has links)
<p>Svest je u poslednje tri decenije postala predmetom multidisciplinarnih studija svesti (consciousness studies), što je aktualizovalo značaj konceptualne analize pojma svesti i problema koji se javljaju u različitim istraţivačkim pristupima svesti. Da li različite discipline (pa čak i različiti pristupi u okviru iste discipline) govore uopšte o istom predmetu? Na šta se, na primer, odnose savremene neurološke teorije svesti, kakav teorijski status ima koncept svesti u okviru funkcionalnih dijagrama kognitivne psihologije, o čemu govore psihoterapeuti kada naglašavaju značaj svesnosti u psihoterapijskom procesu ili značaj osvešćivanja nesvesnog, šta imaju u vidu fenomenolozi ili praktičari kontemplativnih tradicija kada se bave neposrednim iskustvom i na kraju, šta pod svešću podrazumevaju različite ontološke pozicije o odnosu duha i tela? Konceptualna analiza koja je sprovedena u ovom radu ima za cilj poboljšanje komunikacije izmeĎu disciplina i lokalizaciju teškoća koje stoje na putu interdisciplinarnim istraţivačkim projektima.<br />Analitička filozofija duha (philosophy of mind) je u poslednje četiri decenije izoštrila i locirala problematiku svesti, te razvila novi konceptualni aparat i misaone eksperimente koji omogućavaju preciznije razumevanje ograničenja u pokušaju prirodnonaučne rekonstukcije pojma duha (mind), kakvu su poslednjih decenija, inače sa velikim uspehom, preduzele tzv. mind sciences (poput kognitivne psihologije, veštačke inteligencije, lingvistike, neuronauke) . U radu autorka pokazuje kako različiti savremeni filozofi ukazuju na distinkcije dva lica svesti i duha – Dţekendofovo razlikovanje računarskog duha (computational mind) i fenomenološkog duha (phenomenological mind), Blokovo razlikovanje A-svesti (access consciousness) i P-svesti (phenomenal consciousness) i Čalmersovo razlikovanje „lakog“ i „teškog“ problema svesti. Dok se, na primer, A-svest, odnosi na svest u smislu pristupačnosti, odnosno dostupnosti odreĎenog sadrţaja (mentalne reprezentacije) u kontroli govora, rezonovanja i akcije, P-svest (fenomenalna svest) odnosi se na činjenicu da svesna mentalna stanja poseduju doţivljajne, kvalitativne odlike, koje su dostupne direktno jedino iz subjektivne perspektive prvog lica. Za ovaj aspekat svesti je filozofija duha uvela tehnički termin qualia (lat. sing. quale) i on čini svest drugačijom od ostalih predmeta istraţivanja u dominantnoj objektivističkoj naučnoj paradigmi.<br />U radu autorka diskutuje problem ontološkog statusa qualia, kao problem u formulaciji materijalističkih teorija duha (teza o identitetu, funkcionalističke i reprezentacionalističke teorije), kao i epistemološke probleme qualia – problem spoznajno privilegovanog poloţaja, argument nepotpunog znanja (Dţekson) i problem eksplanatornog jaza (Levajn) i njihove reperkusije za filozofiju nauke – problem odnosa metodologije prvog i trećeg lica, razumevanja i objašnjenja, duhovnonaučnog i prirodnonaučnog pristupa čoveku. Iz ovog ugla je u novom svetlu sagledano istorijsko smenjivanje paradigmi u glavnim tokovima akademske psihologije.<br />Sve dosadašnje strategije eliminacije fenomenalne svesti iz psihološkog i filozofskog diskursa vode produbljavanju jaza izmeĎu sveta iskustva (Lebenswelt, Huserl) i prirodnonaučne slike sveta izgraĎene primenom objektivne metodologije. Psihoterapija je, naprotiv, disciplina koja predstavlja jednu od najvaţnijih spona izmeĎu disciplinovanog pristupa subjektivnom iskustvu i objektivnih naučnih činjenica. Zato je paţnja posvećena savremenom konstitusanju psihoterapije kao naučne discipline, kao i njenom pozicioniranju u odnosu na prirodnonaučnu i duhovnonaučnu paradigmu od osnivanja (Frojdovog osciliranja izmeĎu naklonosti prirodnonaučnom modelu i hermeneutičke prakse), preko niza novina i „dekonstrukcija“ prvobitnog modela kroz njenu istoriju, do savremenog trenda – neuropsihoterapije, koja poslednjih deset godina uvodi nova saznanja neuronauke u sagledavanje psihoterapijskog procesa i unapreĎenje postupaka. Analizirani su značaj i uloga koju različiti psihoterapijski pravci (klasična psihoanaliza, BT, KBT, uključujući i nove mindfulness pristupe, egzistencijalistički, humanistički i konstruktivistički pravci) pridaju svesti, svesnosti i osvešćivanju, te koje značenje ovi pojmovi imaju u svetlu distinkcija na koje je ukazala analiza filozofije duha – reprezentaciono tj. funkcionalno-kauzalno i fenomenalno. Pokazano je i kako se epistemološki problemi svesti koji su ranije opisani pojavljuju i rešavaju u psihoterapiji kao praktičnoj disciplini.<br />Integracija fenomenalne svesti u sliku duha, te povezivanje prirodnonaučnih disciplina i disciplina koje se bave iskustvom i subjektivnošču mora da poĎe dalje od konceptualno-logičke analize na kojoj ostaje filozofija duha. Prvi korak na tom putu je razvoj metodologije prvog lica, koja omogućava opis mentalnih procesa i sadrţaja onako kako se oni manifestuju iz ugla svesnog subjekta. Stoga je najpre prikazano šest metoda prvog lica poreklom iz introspektivne psihologije, fenomenološke filozofije i budističke kontemplativne tradicije, a zatim sprovedena tematska kvalitativna analiza ovih metoda. Postupkom otvorenog kodiranja izdvojeno je deset dimenzija po kojima su uporeĎivane metode. Ovo eksplorativno istraţivanje omogućilo je precizniji uvid u meĎusobne srodnosti i razlike analiziranih metoda, u njihove moći i slabosti, te strategije unapreĎenja, kao i u mogućnosti saradnje sa metodama trećeg lica. Pokazali smo takoĎe da „pogled iznutra“ moţe da otkrije vaţne odlike svesti i duha koji ostaju netransparentni objektivnim metodama.</p> / <p>Consciousness has become the subject of multidisciplinary consciousness studies in last three decades which revived the importance of conceptual analysis of the concept of consciousness and problems that occur in a variety of research approaches to consciousness. Do different disciplines (and even different approaches within the same discipline) speak about the same subject at all? What are modern neurological theories of consciousness related to, for example, what is the theoretical status of the concept of consciousness within functional diagrams of cognitive psychology, what do psychotherapists talk about when they highlight importance of awareness in a psychotherapeutic process and importance of becoming aware of the unconscious, what do phenomenologists or practitioners of contemplative traditions have in mind when dealing with direct experience and, in the end, what do different ontological positions imply with the notion of consciousness in the relationship between mind and body? Conceptual analysis conducted in this paper aims to improve communication between disciplines and localize difficulties that stand in the way of interdisciplinary research projects.<br />Analytic philosophy of mind has sharpened and located the problem of consciousness in last four decades, and has also developed a new conceptual apparatus and thought experiments that enable more accurate understanding of limits in an attempt of a natural science reconstruction of the concept of mind, which in recent decades, usually with large success, have been undertaken by so-called mind sciences (such as cognitive psychology, artificial intelligence, linguistics, neuroscience). In this thesis, the author shows how different contemporary philosophers suggest distinctions of two faces of consciousness and mind – Jackendoff’s distinction between computational mind and phenomenological mind, Block’s differentiation of A-consciousness (access consciousness) and P-consciousness (phenomenal consciousness) and Chalmers’ distinction between "easy" and "hard" problems of consciousness. While, for example, A-consciousness, refers to consciousness in terms of accessibility and availability of specific content (mental representations) in the control of speech, reasoning and actions, P-consciousness (phenomenal consciousness) refers to the fact that conscious mental states possess experiential, qualitative characteristics, which are directly available only from the subjective perspective of the first person. Philosophy of mind introduced a technical term qualia (lat. sing. quale) for this aspect of consciousness, and it makes consciousness different from other subjects of research in the dominant objectivist scientific paradigm.<br />In this thesis, the author discusses the problem of the ontological status of qualia, as a problem in the formulation of the materialistic mind theories (the thesis of identity, functionalist and representational theories), as well as epistemological problems of qualia - the problem of privileged access, the argument of incomplete knowledge (Jackson) and the problem of the explanatory gap (Levine) and their repercussions on philosophy of science - the problem of the relationship between first and third-person methodologies, understanding and explanation, a human science and a natural science approach to man. The historical succession of paradigms in the mainstream academic psychology has been viewed from this angle.<br />All previous strategies of eliminating phenomenal consciousness from psychological and philosophical discourse lead to deepening of the gap between the world of experience (Lebenswelt, Husserl) and the natural science picture of the world constructed by using an objective methodology. Psychotherapy, on the contrary, is a discipline that is one of the most important links between a disciplined approach to subjective experience and objective scientific facts. That is why attention has been paid to the contemporary constitution of psychotherapy as a scientific discipline, as well as its positioning in relation to a natural science and a human science paradigm since its establishment (Freudian oscillating between the affection to natural scientific model and hermeneutical practice), through a number of novelties and "deconstructions" of the original model through its history, to the modern trend – neuropsychotherapy which has introduced new findings of neuroscience in understanding psychotherapeutic processes and improvement of procedures in last ten years. We analyzed the importance and the role that different psychotherapeutic views (classical psychoanalysis, BT, CBT, including new mindfulness approaches, existentialist, humanistic and constructivist views) attach to consciousness, awareness, and raising awareness, as well as the meanings of these terms in the light of distinctions identified by the analysis of philosophy of mind - that is, representational, functional-causal, and phenomenal. It was shown how the epistemological problems of consciousness described above occur and get resolved in psychotherapy as a practical discipline.<br />Integration of phenomenal consciousness into an image of the mind, and connection of natural science disciplines and disciplines which deal with experience and subjectivity has to go beyond a conceptual and logical analysis on which philosophy of mind remains. The first step on this road is development of a first-person methodology, which allows a description of mental processes and content as they are manifested from a perspective of a conscious subject. Therefore, the first things presented were six first-person methods originating from introspective psychology, phenomenological philosophy and Buddhist contemplative tradition, and then, a qualitative thematic analysis of the six methods was conducted. The process of open coding singled out ten dimensions by which methods were compared. This exploratory research has allowed for a more precise insight into mutual similarities and differences of the analyzed methods, into their powers and weaknesses, improvement strategies, as well as opportunities for cooperation with third-person methods. It has shown also that “a view from within" can reveal important features of consciousness and mind that remain non-transparent to objective methods.</p>
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Imunohromatografski test u diferencijalnoj laboratorijskoj dijagnostici tuberkuloze pluća / Immunochromatographic test in differential laboratory diagnostic of tuberculosisSavković Tijana 01 April 2016 (has links)
<p>UVOD: Tuberkuloza je odavno poznata bolest koja i danas u 21. veku još uvek predstavlja veliki javnozdravstveni problem, uprkos primeni moćnih antituberkuloznih lekova. Trećina svetske populacije inficirana je bacilom tuberkuloze. Svake godine oboli oko osam miliona, a umre oko dva miliona ljudi, zbog čega je tuberkuloza i dalje infektivno oboljenje sa najvećom stopom smrtnosti. Kasna dijagnoza, multirezistentna tuberkuloza i udruženost sa HIV infekcijom predstavljaju jednu od najvećih prepreka za efikasnu kontrolu ove bolesti u svetu. Rano otkrivanje se oslanja na kvalitetnu bakteriološku dijagnostiku koja je kamen temeljac svakog nacionalnog programa za kontrolu tuberkuloze. Brza i tačna mikrobiološka dijagnostika predstavlja osnovu programa kontrole tuberkuloze i zbog toga je uvođenje novih i brzih laboratorijskih testova od veoma velikog značaja. Razvijen je novi komercijalno dostupni imunohromatografski test koji se zasniva na detekciji antigena MPT64 glavnog sekretovanog proteina M. tuberculosis. Test je brz i pouzdan u identifikaciji izolovanih sojeva M. tuberculosis i jeftiniji je od konvencionalnih biohemijskih i molekularnih testova. CILJ: Ciljevi istraživanja su bili da se evaluiraju karakteristike novog brzog imunohromatografskog testa u identifikaciji mikobakterija izolovanih iz respiratornih uzoraka bolesnika sa tuberkulozom pluća i referentnih sojeva klinički značajnih vrsta netuberkuloznih mikobakterija (NTM). MATERIJAL I METODE: Istraživanje je sprovedeno u periodu od 1.1.2010. do 31.12.2013. i obuhvatilo je 43563 respiratornih uzoraka dobijenih od bolesnika hospitalizovanih u Institutu za plućne bolesti Vojvodine. Iz obrađenih respiratornih uzoraka izolovano je 3469 izolata mikobakterija. Identifikacija do nivoa vrste urađena je primenom standardnih biohemijskih testova, molekularnog testa (GenoType® Mycobacterium) i imunohromatografskog testa (BDMGIT Tbc). U istraživanje je uključeno 100 sojeva Gram pozitivnih i Gram negativnih bakterija (n = 19 vrsta) izolovanih iz respiratornih kliničkih uzoraka. Identifikacija do nivoa vrste je potvrđena komercijalnim identifikacionim sistemima. REZULTATI: U toku četvorogodišnjeg istraživanja izolovano je 3469 izolata mikobakterija iz respiratornih uzoraka. U ispitivanom periodu ne postoji opadajući trend izolacije mikobakterija što potvrđuje i koeficijent korelacije (r = 0,31). Svi izolati mikobakterija su identifikovani konvencionalnim biohemijskim ispitivanjima koja pokazuju da je 89% od svih izolata identifikovano kao Mycobacterium tuberculosis (M. tuberculosis), a 11% izolata kao NTM. Mycobacterium xenopi je bila najzastupljenija NTM vrsta identifikovana kod 55,3% izolata. Nakon biohemijske identifikacije kod 300 izolata M. tuberculosis i 100 izolata NTM, identifikacija je potvrđena komercijalno dostupnim molekularnim i imunohromatografskim testom. Na osnovu rezultata testiranja mikobakterija imunohromatografskim testom, senzitivnost, specifičnost, pozitivne i negativne prediktivne vrednosti bile su: 99,7%, 100%, 100% i 99%. U poređenju imunohromatografskog testa sa konvencionalnim biohemijskim ispitivanjima nije nađena statistički značajna razlika (p> 0,5). Kappa vrednost testa je iznosila 0,993, a interval poverenja CI =0,98 – 1,00. U poređenju imunohromatografskog sa molekularnim testom vrednost kappa je iznosila 0,993, a interval poverenja CI = 0,98 – 1,00. Slaganje rezultata je potvrđeno i McNemar testom sa vrednošću 0,99. Utvrđena je stabilnost sekretovanog antigena MPT64 i posle 5 godina od prvog testiranja. ZAKLJUČAK: Visoka senzitivnost i specifičnost imunohromatografskog testa omogućuju tačnu i preciznu identifikaciju M. tuberculosis kao i pouzdanu diferencijaciju M.tuberculosis od NTM – a. Imunohromatografski test može da predstavlja zamenu za konvencionalne biohemijske i molekularne testove u identifikaciji M. tuberculosis. Jeftiniji je, jednostavniji za izvođenje i brže se dobijaju rezultati čime seskraćuje vreme za postavljanje dijagnoze.</p> / <p>INTRODUCTION: Tuberculosis (TB) has been known as a disease for a long time, but nevertheless it represents a major public health issue even nowadays in the 21st century, despite potent antituberculous drugs applied. One third of the world population is infected by the TB bacillus. About eight million people get infected and two million die of tuberculosis in a year, so tuberculosis is still an infectious disease with the greatest mortality rate. Late diagnosis, multiresistant tuberculosis and concomitant HIV infection interfere mostly with an efficient control of the disease all over the world. Early TB detection largely depends on the high-quality bacteriological diagnostics, which is the corner stone of each national TB control programme. A fast and accurate microbiological TB diagnosis plays a crucial role in any TB control programme. It is therefore very important to introduce new and fast laboratory tests. A novel commercially available immunochromatographic test has been designed, based on the MPT64 antigen of the major M. tuberculosis – secreted protein. This is a rapid and reliable test to identify the isolated strains of M. tuberculosis, which is not expensive as conventional biochemical and molecular tests. OBJECTIVE: The objective of the investigation was to evaluate the new immunochromatographic rapid test to identify mycobacteria isolated from respiratory samples from pulmonary TB patients, and referential strains of clinically relevant species of nontuberculous mycobacteria (NTM). MATERIAL AND METHODS: The research was carried out in the period from 1st January, 2010 to 31st December, 2013. It included 43 563 respiratory samples obtained from the patients hospitalized in the Institute for Pulmonary Diseases of Vojvodina, Sremska Kamenica (Serbia). There were 3 469 mycobacterial isolates obtained from the processed respiratory samples. The species – level identification was performed by standard biochemical tests, the molecular test (GenoType®Mycobacterium), and the immunochromatographic test (BD MGIT Tbc). The study included one hundred (100) of Gram positive and Gram negative bacteria (n = 19 species) isolated from respiratory clinical samples. The species – level identification was confirmed by commercial identification systems. RESULTS: During the four – year investigation, 3 469 mycobacterial isolates were obtained from respiratory samples. No declining tendency of mycobacterial isolation was registered in the examined period, as confirmed by the correlation coefficient (r = 0.31). All mycobacterial isolates were identified by conventional biochemical tests showing that 89% of all isolates were identified as M. tuberculosis, and 11% of the isolates as NTM. Mycobacterium xenopi was the most common NTM species identified in 55.3% of the isolates. Following the biochemical identification in 300 M. tuberculosis isolates and 100 NTM isolates, the identification was confirmed by commercially available molecular and immunochromatographic tests. Based on immunochromatographic testing of mycobacteria, the sensitivity, specificity, positive and negative predictive values of the test were 99.7%, 100%, 100% and 99% respectively. There is no statistically significant difference (p> 0.5) when comparing features of immunochromatographic test with conventional biochemical assay. The kappa test value was 0.993, and the confidence interval CI = 0.98 – 1.00. Comparing the immunochromatographic with the molecular test, the kappa value was 0.993, and the confidence interval CI = 0.98 – 1.00. The congruence of the tests findings was also confirmed by the McNemar test, estimated to 0.99. The stability of the secreted MPT64 antigen was registered even five years after the first testing episode. CONCLUSION: The high sensitivity and specificity of the imunochromatographic test enable an accurate and precise identification of M. tuberculosis, as well as a reliable differentiation of M. tuberculosis from NTM. The immunochromatographic test may substitute conventional biochemical and molecular tests to identify M. tuberculosis. It is easier to perform and provides faster test results, thus reducing the time of establishing the diagnosis.</p>
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Корелација клинички и патохистолошки одређене латералне маргине код базоцелуларног карцинома коже / Korelacija klinički i patohistološki određene lateralne margine kod bazocelularnog karcinoma kože / Correlation of the clinically and histopathologically determined lateral margin of the basal cell skin cancerGajić Branislava 08 July 2016 (has links)
<p>Увод. Базоцелуларни карцином коже (БЦК) је спорорастући малигни епидермални тумор. овај најчешћи тумор у људи иако врло ниског метастатског потенцијала може бити високо инвазиван и значајно допринети морбидитету, угрозити функцију и естетику регије, па и сам живот. Лечење БЦК има за циљ: уклањање тумора, очување здравог ткива и функције, оптимални козметски резултат. Најчешћи вид лечења БЦК је једноставна хируршка ексцизија. Према важећим препорукама БЦК се ексцидирају са заштитним маргинама од 5-10 mm. Одређени броју студија показују директно или индиректно да је клинички одређена маргина врло слична реалној. Оцена адекватности клиничке процене у односу на хистолошку маргину тумора није довољно испитивана. Стопа комплетне ексцизије БЦК (излечење) се не повећава значајно са повећањем сигурносне маргине Циљ истраживања је установљавање односа повезаности између клиничке процене и микроскопски утврђене латералне маргине БЦК на хистолошком препарату. Методологија. У обради узорка од 45 испитаника узети су циљани анамнестички подаци, спроведен клинички преглед, уобичајена хируршке терапије и класична патохистолошка обрада узорака. У методолошкој обради 60 узорака тумора интраоперативно врхом хируршког скалпела целом циркумференцијом клиничке маргине тумора начињен је зарез до нивоа папиларног дермиса. Пре ексцизије додата је заштитна маргина од 4-5 mm. Класична патохистолошка обрада је спроведена као и преглед препарата светлосним микроскопом различитог увеличања (х 40, х 100, х 200, х400). Мерење дистанце између начињеног зареза, и хистолошке границе тумора вршена је уз помоћ милиметарског окулара. Сви добијени подаци унети су у заједничку базу података. За статистичку обраду података коришћен је програм СПСС 21. Коришћене су методе методе дескриптивне статистике, униваријантне и мултивасријантне анализе. Резултати су приказани табеларно и графички, а комплетан рад је обрађен у текст процесору MS Word. Резултати. У 96,7% ексцидираних БЦК удаљеност зареза од патохистолошке маргине тумора је мања од 2,0 мм, док је у два тумора (3,3%) зарез на удаљености 2 и преко 2мм. У четвртини узорка (25%) зарез се налази у тумору, а 75% узорка зарез је начињен ван хистолошке границе тумора. Закључак. Разлика између клинички обележене и микроскопом измерене латералне маргине је у више од 95%, односно у 96,7% мања од 2 mm. У 88,4% случајева ова разлика у процени је 1mm или мање од 1mm. Постоји позитивна корелација између клинички процењене и патохистолошки одређене латералне маргине БЦК. Иако се поједини предиктивни фактори који утичу на лошију клиничку процену могу издвојити, истраживање није показало статистичи значајне предиктивне факторе.</p> / <p>Uvod. Bazocelularni karcinom kože (BCK) je spororastući maligni epidermalni tumor. ovaj najčešći tumor u ljudi iako vrlo niskog metastatskog potencijala može biti visoko invazivan i značajno doprineti morbiditetu, ugroziti funkciju i estetiku regije, pa i sam život. Lečenje BCK ima za cilj: uklanjanje tumora, očuvanje zdravog tkiva i funkcije, optimalni kozmetski rezultat. Najčešći vid lečenja BCK je jednostavna hirurška ekscizija. Prema važećim preporukama BCK se ekscidiraju sa zaštitnim marginama od 5-10 mm. Određeni broju studija pokazuju direktno ili indirektno da je klinički određena margina vrlo slična realnoj. Ocena adekvatnosti kliničke procene u odnosu na histološku marginu tumora nije dovoljno ispitivana. Stopa kompletne ekscizije BCK (izlečenje) se ne povećava značajno sa povećanjem sigurnosne margine Cilj istraživanja je ustanovljavanje odnosa povezanosti između kliničke procene i mikroskopski utvrđene lateralne margine BCK na histološkom preparatu. Metodologija. U obradi uzorka od 45 ispitanika uzeti su ciljani anamnestički podaci, sproveden klinički pregled, uobičajena hirurške terapije i klasična patohistološka obrada uzoraka. U metodološkoj obradi 60 uzoraka tumora intraoperativno vrhom hirurškog skalpela celom cirkumferencijom kliničke margine tumora načinjen je zarez do nivoa papilarnog dermisa. Pre ekscizije dodata je zaštitna margina od 4-5 mm. Klasična patohistološka obrada je sprovedena kao i pregled preparata svetlosnim mikroskopom različitog uveličanja (h 40, h 100, h 200, h400). Merenje distance između načinjenog zareza, i histološke granice tumora vršena je uz pomoć milimetarskog okulara. Svi dobijeni podaci uneti su u zajedničku bazu podataka. Za statističku obradu podataka korišćen je program SPSS 21. Korišćene su metode metode deskriptivne statistike, univarijantne i multivasrijantne analize. Rezultati su prikazani tabelarno i grafički, a kompletan rad je obrađen u tekst procesoru MS Word. Rezultati. U 96,7% ekscidiranih BCK udaljenost zareza od patohistološke margine tumora je manja od 2,0 mm, dok je u dva tumora (3,3%) zarez na udaljenosti 2 i preko 2mm. U četvrtini uzorka (25%) zarez se nalazi u tumoru, a 75% uzorka zarez je načinjen van histološke granice tumora. Zaključak. Razlika između klinički obeležene i mikroskopom izmerene lateralne margine je u više od 95%, odnosno u 96,7% manja od 2 mm. U 88,4% slučajeva ova razlika u proceni je 1mm ili manje od 1mm. Postoji pozitivna korelacija između klinički procenjene i patohistološki određene lateralne margine BCK. Iako se pojedini prediktivni faktori koji utiču na lošiju kliničku procenu mogu izdvojiti, istraživanje nije pokazalo statističi značajne prediktivne faktore.</p> / <p>Introduction. Basal cell carcinoma of the skin (BCC) is a slow-growing malignant tumor of epidermis. This most frequent tumour in humans, with a low metastatical potential, can be highly invasive and add significantly to the morbidity rate; it can jeopardize the function and aesthetics of the region as well as one's life itself. Treatment of BCC aims to remove the tumor, preserve healthy tissue and function, and obtain optimal cosmetic result. Simple surgical excision is the most frequent therapeutic option. Current recommendations for surgical excision margins range from 5 to 10mm. A certain number of studies shows either directly or indirectly that the clinical margin is approximately similar to the hystology margin. Estimation of the clinical assesment in relation to the histological margine of tumor has not been sufficiently examined. Incresing the safety margins does not significantly increase the rate of completely excised BCC. Aim. The aim of the research is to establish the relationship between the clinical assessment and microscopically determined lateral margins of BCC in histopathological sample. Methods. In 45 patients, selected data from anamnesis have been taken, clinical examination has been conducted, as well as a regular surgical treatment, and a classical histopathological evaluation of samples. In 60 samples of the tumours intraoperatively, an circumferential incision at the clinical margin with the tip of surgical knife to the level of papillary dermis is made. Prior to the excision an additional safety margin is added. A standard histopathological processing, microscopic examination with various magnification range (40x, 100x, 200x, 400x) and the measurement of the distance between the incision and the histological margin of tumor was done with the milimetar graded ocular. All the data have entries in the common database. Statistical data processing was conducted by the statistical package SPSS 21. The following methods were used: descriptive statistics, univariate analysis and multivariate analysis. The results are given in tables and graphs and the entire study was processed by MS Word. Results. In 96,7% of the excided BCC the distance of the incision from the histopathological margin of the tumor is less than 2,0mm, while in the two tumors (3,3%) incision made was 2mm and over 2mm. In one quarter of the samples (25%) the incision is made in the tumor, and in 75% of them it is made outside the limits of its histological margin. Conclusion. The difference between the clinical estimation of lateral margin and histopathological margin of the tumor in 97% of the cases is less than 2mm. In 88,4% of the cases this difference amounts to 1mm or less than 1mm. There is a positive correlation between the clinically estimated and histopathological margins of the tumor. Although there are certain predictive factors that can influence somewhat worse clinical estimation, the research did not show statistically important predictive factors.</p>
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Histološke odlike mukoze želuca svinja u različitim uslovima uzgoja / Histologic features of gastric mucosa of pigs in different production systemsPejčinovska Nataša 21 September 2018 (has links)
<p>Bakterije koje kolonizuju želudac (Gastrospirillum spp. i Helicobacter spp.) su izolovane kod čoveka i nekoliko animalnih vrsta, uključujući i svinje. Gastritis je rezultat prirodne ili eksperimentalno izazvane infekcije sa H. pylori kod čoveka i konvencionalnih prasića. Kod obe vrste (čovek i svinja), infekcija sa H. pylori pokreće inflamatorni odgovor organizma, međutim postoje razlike u ćelijskoj populaciji u inflamatornom infiltratu. Cilj istraživanja ove disertaciji je identifikacija bakterije Helicobacter spp., različite morfologije (Helicobacter-like organisms and Gastrospirillum-like organisms), kao i patohistološki pregled i evaluacija gastritisa svinja uzgajanih na intenzivni i ekstenzivni način. Uzeti su uzorci mukoze pars oesophagea, fundusa i pilorusa. Za identifikaciju bakterije Helicobacter spp. korišćene su dve metode bojenja: Loefflermethylene blue i modifikovana Giemsa. Za histološko ispitivanje, uzorci su obojeni i hematoksilin eozinom (H&E). Stepen gastritisa je određen prema Sidnejskom sistemu za klasifikaciju gastritisa. U humanoj a i u veterinarskoj patologiji, dobro je poznata činjenica o različitoj patogenosti različitih bakterija Helicobacter vrsta. Helicobacter bakterije izolovane iz želuca svinja pripadaju različitim vrstama ovog roda i međusobno se bitno razlikuju kako po patogenosti, tako i po virulentnosti. Tako na primer, Helicobacter–like bakterije koje su okarakterisane kao visoko patogene, mogu izazvati ulceracije ezofagealnog ili glandularnog dela želuca, gastritis ozbiljnog stepena i formiranje limfoidnih folikula. Rezultati našeg istraživanja pokazuju da je stepen gastritisa veći u piloričnoj mukozi HLO-pozitivnih svinja u poređenju sa vrednostima GLO-pozitivnih svinja. Nije postojala pozitivna korelacija između infekcije bakterijama GLO morfologije i ulceracija. Za razliku od perzistentnih infekcija sa H. pylori kod ljudi kod kojih je teška glandularna atrofija udružena sa intestinalnom metaplazijom veoma česta, kod ispitivanih svinja iz</p><p><br /><br />intenzivnog i ekstenzivnog načina uzgoja nisu potvrđeni slučajevi atrofičnog gastritisa i intestinalne metaplazije. Konvencionalne svinje mogu poslužiti kao animalni model infekcije sa H. pylori jer su svinje u funkcionalnom smislu monogastrične životinje po anatomskim i fiziološkim karakteristikama, vrlo slične čoveku. Takođe, patogeneza infekcije je veoma slična kao kod čoveka. Navedene činjenice podržavaju mogućnost upotrebe ovog modela u daljem istraživanju patogeneze nastanka Helicobacter spp. gastritisa. Rezultati ovog istraživanja pružaju dodatni dokaz da HLO mogu biti faktor koji igra krucijalnu ulogu u patogenezi gastritisa kod svinja. <br />Datum</p> / <p>Bacteria that colonize the stomach (Helicobacter spp. and Gastrospirillum spp.) are isolated from humans and several animal species, including pigs. Gastritis is the result of a natural or experimental induced infection with H. pylori in humans and conventionally pigs. In both, humans and pigs, the infection with H. pylori elicited inflammatory response, but there are differences between populations of inflammatory cells. The aims of this dissertation are to identify spp. with two different morphology (Helicobacter-like organisms and Gastrospirillumlike organisms), as well as histolopathological examination and evaluation of gastritis score of gastric mucosa of pigs in intensive and extensive production. Biopsy samples were taken from the pars oesophagea, fundic and pyloric mucosa. For identification of Helicobacter species morphology we used two stain methods: Loeffler-methylene blue and modified Giemsa. All tissue sections were stained with hematoxylin and eosin (H&E) for histopathological evaluation. The severity of gastritis was scored to the Sydney System for the classification of gastritis. In human as well as in veterinary pathology, the fact of the different pathogenicity of various Helicobacter species is well known. The Helicobacter spp. isolated from stomach mucosa of pigs which belong to different genus, differ significantly in both, pathogenicity and virulence. Helicobacter pylori-like bacteria characterised as high pathogenic, has been associated with ulceration of the oesophageal or glandular portion of the stomach, severe gastritis and formation of lymphoid follicles. On the contrast, infection with Helicobacter heilmannii, which has been shown to have low pathogenicity was accompanied by only mild gastritis and no ulceration. The results of current study suggested that the average gastritis score was higher in HLO-positive pyloric mucosa, compared</p><p><br /><br />with the GLO-positive pyloric mucosa. There was signifficance between HLO-positive and HLO-negative pyloric mucosa in both, intensive and extensive production. There was no correlation between GLO-positive mucosa and ulceration. In contrast to persistent H. pylori infection in humans in which severe glandular atrophy associated with intestinal metaplasia is very common, in examined pigs from intensive and extensive breeding, no samples exhibited histological features characteristic for atrophic gastritis and intestinal metaplasia have been confirmed in pigs of both production systems. The conventional piglets as an animal model of the human H. pylori infection offers advantages of a functional monogastric animal with gastric anatomic and physiologic characteristics similar to those of humans. Moreover, the infection and pathogenesis is similar to that in humans. These facts support the usefulness of this model in further research on the pathogenic mechanisms of Helicobacter spp. associated gastritis. Our findings provide further evidence that HLO can be one of the factors that playing a crucial role in the pathogenesis of gastritis in pigs.<br />Accepted</p>
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