541 research outputs found
Dissertation: Behavior of martensitic wear resistant steels in abrasion and impact wear testing conditions
The doctoral dissertation of Vilma Ratia in the field of materials engineering entitled “Behavior ofMartensitic Wear Resistant Steels in Abrasion and Impact Wear Testing Conditions” was publiclyexamined at the Faculty of Engineering Sciences of Tampere University of Technology (TUT) on6th of November, 2015. The opponents were Professor Mikael Olsson (Dalarna University,Sweden) and Dr. Mikko Uusitalo (Valmet Technologies, Inc.). Professor Veli-Tapani Kuokkalafrom the Department of Materials Science at TUT acted as the Chairman
IGF-1 enhances the osteogenic activity of BMP-6 in vitro and in vivo, and together have a stronger osteogenic effect than when IGF-1 is combined with BMP-2
Bone morphogenetic protein-2 (BMP-2) is widely used in orthopedic surgery and bone tissue engineering because of its strong osteogenic activity. However, BMP-2 treatments have several drawbacks and alternatives are being explored. Since BMP-6 has been demonstrated to be more osteoinductive, its use, either alone or together with other cytokines, might be an interesting option.
We have compared the effect of BMP-2, BMP-6, or insulin-like growth factor-1 (IGF-1), either alone or in combination. MC3T3-E1 cells were treated with IGF-1 and/or of BMP-2 or -6 and the expression of osteogenic genes, proliferation and alkaline phosphatase (ALP) activity in vitro were analyzed. The results showed that IGF-1 greatly enhanced the BMP-induced osteogenic differentiation of these cells and that the ALP activity in the cultures was higher when the combination was made with BMP-6 than with BMP-2. Other in vitro experiments showed that the osteogenic effect of these combinations can be modulated controlling the sequential administration of the growth factors.
Furthermore, we have tested the osteogenic potential of these treatments in vivo by loading them onto absorbable collagen sponges which were implanted into an ectopic bone formation model in rats. These experiments revealed that only BMP-6 was able to induce bone formation at the used dose and that the addition of IGF-1 contributed to an increase of the mineralization in the implants.
Hence, the combination of BMP-6 with IGF-1 might be a better alternative than BMP-2 for orthopedic surgery and bone tissue engineering approaches with potential application through using controlled delivery systems.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
IGF-1 enhances the osteogenic activity of BMP-6 in vitro and in vivo
Bone morphogenetic protein-2 (BMP-2) is widely used in orthopedic surgery and bone tissue engineering because of its strong osteogenic activity. However, BMP-2 treatments have several drawbacks and alternatives are being explored. Since BMP-6 has been demonstrated to be more osteoinductive, its use, either alone or together with other cytokines, might be an interesting option.
We have compared the effect of BMP-2, BMP-6, or insulin-like growth factor-1 (IGF-1), either alone or in combination. MC3T3-E1 cells were treated with IGF-1 and/or of BMP-2 or -6 and the expression of osteogenic genes, proliferation and alkaline phosphatase (ALP) activity in vitro were analyzed. The results showed that IGF-1 greatly enhanced the BMP-induced osteogenic differentiation of these cells and that the ALP activity in the cultures was higher when the combination was made with BMP-6 than with BMP-2. Other in vitro experiments showed that the osteogenic effect of these combinations can be modulated controlling the sequential administration of the growth factors.
Furthermore, we have tested the osteogenic potential of these treatments in vivo by loading them onto absorbable collagen sponges which were implanted into an ectopic bone formation model in rats. These experiments revealed that only BMP-6 was able to induce bone formation at the used dose and that the addition of IGF-1 contributed to an increase of the mineralization in the implants.
Hence, the combination of BMP-6 with IGF-1 might be a better alternative than BMP-2 for orthopedic surgery and bone tissue engineering approaches with potential application through using controlled delivery systems.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
Conversion rate optimization in Finnish online businesses
Conversion rate optimization (CRO) is an unfamiliar term to many online business owners even though it has become almost as important as search engine optimization is in e-commerce today. It is a method that is used to turn passive visitors into active users in order to improve a website’s performance.
The main objective of this thesis was to find out what kinds of conversion rate optimization methods do Finnish small and medium-sized online businesses use. The thesis also studies what are Finnish e-business consultants’ opinions of online businesses’ CRO awareness and how do their opinions differ from the online business owners’ opinions on the matter. Additionally, the authors aimed to find out if there is a need to inform online businesses of CRO, especially of its benefits and methods.
Data was collected by sending a web survey to randomly selected Finnish SME (small and medium-sized) online businesses and by interviewing Finnish e-business consultants. The data was analyzed by using qualitative research methods.
The results suggest that conversion rate optimization is a relatively unfamiliar concept to Finnish online businesses. The interviewed consultants also agreed that online businesses’ knowledge about conversion rate optimization is generally poor.
The online businesses that had implemented CRO in their website almost solely used A/B testing as a method. However, some surveyed online businesses thought that they should be informed more about conversion rate optimization, and its benefits and methods.Konversio-optimointi on monille verkkokaupan omistajille tuntematon termi, vaikka se onkin kohonnut lähes yhtä tärkeäksi osaksi verkkokaupankäyntiä kuin hakukoneoptimointi. Se on menetelmä, jonka avulla verkkokaupan suorituskykyä parannetaan muuttamalla verkkosivuston passiiviset vierailijat aktiivisiksi käyttäjiksi.
Tämän opinnäytetyön tarkoitus on selvittää, minkälaisia konversio-optimoinnin menetelmiä suomalaiset pienet ja keskikokoiset verkkokaupat käyttävät. Opinnäytetyössä tutkitaan myös, mikä on suomalaisten sähköisen liiketoiminnan konsulttien mielipide verkkokauppojen tietämyksestä konversio-optimoinnin suhteen. Lisäksi tutkimuksessa otetaan selvää onko konversio-optimoinnin, sen hyötyjen ja menetelmien tiedottamiselle kysyntää verkkokauppojen keskuudessa.
Tieto kerättiin lähettämällä verkkokysely satunnaisesti valituille suomalaisille PK-verkkokaupoille ja haastattelemalla suomalaisia sähköisen liiketoiminnan konsultteja. Tieto analysoitiin käyttämällä kvalitatiivisia tutkimusmenetelmiä.
Tutkimuksessa kävi ilmi, että konversio-optimointi on melko vieras käsite suomalaisille verkkokaupoille. Myös haastatellut konsultit olivat sitä mieltä, että verkkokauppojen tietoisuus konversio-optimoinnista on erittäin vähäistä.
Ne verkkokaupat, jotka sitä ovat soveltaneet sivuilleen, käyttävät lähes ainoana menetelmänä A/B testausta. Osa verkkokyselyyn vastanneista verkkokaupoista oli kuitenkin sitä mieltä, että konversio-optimoinnista, sen hyödyistä ja menetelmistä pitäisi tiedottaa enemmän
Presència de radionúclids d'origen mèdic en el medi
La presència de radionĂşclids en el medi i conseqĂĽentment la caracteritzaciĂł radiològica de les mostres on aquests estan presents Ă©s una temĂ tica d’estudi de gran interès per a la comunitat cientĂfica. Aquests radionĂşclids poden estar presents en el medi de manera natural o bĂ© poden ser introduĂŻts per diverses fonts d’origen artificial. Entre aquestes Ăşltimes, destaca la incorporaciĂł de radionĂşclids en el medi relacionada amb la prĂ ctica de la medicina, particularment, la branca de la medicina nuclear en la qual es manipulen i administren radionĂşclids en forma de fonts radioactives no encapsulades. En aquest context, la present Tesi Doctoral pretĂ©n contribuir a aportar nous coneixements en relaciĂł a la presència i el comportament de radionĂşclids artificials d’origen mèdic, principalment 99mTc i 131I, en mostres ambientals i biològiques tant de l’interior com de l’exterior d’un centre mèdic de la provĂncia de Tarragona. Concretament, s’han caracteritzat radiològicament mostres d’aire de l’entorn laboral del departament de medicina nuclear i mostres biològiques dels treballadors del mateix departament, aixĂ com mostres d’aigua residual i altres procedents d’estacions de tractament d’aigua potable i residual de la zona. La tècnica radioquĂmica de mesura emprada ha estat l’espectrometria gamma ja que tots els radionĂşclids avaluats sĂłn emissors d’aquest tipus. Alguna de les mostres ha necessitat l’aplicaciĂł de diversos pretractaments basats en l’evaporaciĂł o la precipitaciĂł selectiva del radionĂşclid a analitzar. Per altra banda, tambĂ© s’ha realitzat una estimaciĂł la dosi efectiva a la que un treballador d’un departament de medicina nuclear o d’una estaciĂł de tractament d’aigua residual podria rebre pel fet d’estar exposat a la presència de radionĂşclids mèdics en el seu entorn laboral.La presencia de radionucleidos en el medio y consecuentemente la caracterizaciĂłn radiolĂłgica de las muestras donde estos están presentes es una temática de estudio de gran interĂ©s para la comunidad cientĂfica. Estos radionĂşclidos pueden estar presentes en el medio de manera natural o bien pueden ser introducidos por diversas fuentes de origen artificial. Entre estas Ăşltimas, destaca la incorporaciĂłn de radionucleidos en el medio relacionada con la práctica de la medicina, particularmente, la rama de la medicina nuclear en la que se manipulan y administran radionucleidos en forma de fuentes radiactivas no encapsuladas. En este contexto, la presente Tesis Doctoral pretende contribuir a aportar nuevos conocimientos en relaciĂłn a la presencia y el comportamiento de radionucleidos artificiales de origen mĂ©dico, principalmente 99mTc y 131I, en muestras ambientales y biolĂłgicas tanto del interior como del exterior de un centro mĂ©dico de la provincia de Tarragona. Concretamente, se han caracterizado radiolĂłgicamente muestras de aire del entorno laboral del departamento de medicina nuclear y muestras biolĂłgicas de los trabajadores del mismo departamento, asĂ como muestras de agua residual y otros procedentes de estaciones de tratamiento de agua potable y residual de la zona. La tĂ©cnica radioquĂmica de medida empleada ha sido la espectrometrĂa gamma ya que todos los radionucleidos evaluados son emisores de este tipo. Alguna de las muestras ha necesitado la aplicaciĂłn de diversos pretratamientos basados en la evaporaciĂłn o la precipitaciĂłn selectiva del radionucleido a analizar. Por otra parte, tambiĂ©n se ha realizado una estimaciĂłn la dosis efectiva a la que un trabajador de un departamento de medicina nuclear o de una estaciĂłn de tratamiento de agua residual podrĂa recibir por estar expuesto a la presencia de radionucleidos mĂ©dicos en su entorno laboral.The presence of radionuclides in the environment and consequently the radiological characterization of the samples where they are present is a subject of study of great interest to the scientific community. These radionuclides can be naturally present in the environment or they can be introduced through artificial sources. Among the latter, the incorporation of radionuclides in the environment is related to the practice of medicine particularly, the branch of nuclear medicine in which radionuclides are handled and administered in the form of non-encapsulated radioactive sources. In this context, this Doctoral Thesis aims to contribute to providing new knowledge in relation to the presence and behavior of artificial radionuclides of medical origin, mainly 99mTc and 131I, in environmental and biological samples both from inside and outside a medical center of the province of Tarragona. Specifically, air samples of the work environment of the nuclear medicine department and biological samples of the workers of the same department have been radiologically characterized, as well as samples of wastewater and other samples from drinking and wastewater treatment stations in the area. The radiochemical measurement technique used has been gamma spectrometry since all radionuclides evaluated are emitters of this type. Some of the samples have required the application of various pretreatments based on evaporation or selective precipitation of the radionuclide to be analyzed. On the other hand, an assessment of the effective dose at which a worker in a nuclear medicine department or a wastewater treatment station could receive for being exposed to the presence of medical radionuclides in their work environment has been made
The History of Ceremonial Conferments in Turku
The history of ceremonial conferments organised by European universities goes back to the Middle Ages, as bachelors were conferred as masters in Paris and Bologna already in the 13th century. From the European universities, the tradition of conferring academic degrees spread to Sweden, where the ceremony was first organised at the Uppsala University in 1600 and at the Royal Academy of Turku in 1643. At that time, Finland and Turku were part of the Swedish kingdom and the Royal Academy of Turku, founded in 1640, was the first university in Finland. This university was situated in Turku until the great fire of 1827, after which the university was moved to Helsinki, the new capital of Finland. Ceremonial conferments have been an important celebration for the community, as not only does the ceremony confer scholars as part of the academic community, but it also builds internal hierarchy and symbolism.The history of ceremonial conferments organised by European universities goes back to the Middle Ages, as bachelors were conferred as masters in Paris and Bologna already in the 13th century. From the European universities, the tradition of conferring academic degrees spread to Sweden, where the ceremony was first organised at the Uppsala University in 1600 and at the Royal Academy of Turku in 1643. At that time, Finland and Turku were part of the Swedish kingdom and the Royal Academy of Turku, founded in 1640, was the first university in Finland. This university was situated in Turku until the great fire of 1827, after which the university was moved to Helsinki, the new capital of Finland. Ceremonial conferments have been an important celebration for the community, as not only does the ceremony confer scholars as part of the academic community, but it also builds internal hierarchy and symbolism
The effect of combining bone morphogenetic proteins -2 and -6 on osteoblastic differentiation and bone
Bone morphogenetic proteins-2 and -7 (BMP-2 and -7) are the only two members of the BMP subfamily approved to date to be used in combination with collagen type I in orthopedic surgery, although other BMPs have proven to also be highly osteoinductive. All the osteogenic BMPs signal through Smad-1/-5/-8 phosphorylation, but they have different preferences for the BMP receptors they use.
Very high supraphysiological doses of BMPs have been used in the clinics for the treatment of non-union fractures and spinal fusions. Besides the high cost of these treatments, safety concerns have been recently raised. Hence there is an active field in finding alternatives to the most classical collagen + BMP-2 system.
The aim of this work was to study the effect of combining two osteogenic BMPs (-2 and -6) belonging to different groups within the subfamily, and with different affinities to the existing BMP receptors. Both the growth and osteoblastic differentiation of MC3T3-E1 mouse preosteoblasts and rat bone marrow-derived mesenchymal stem cells (MSCs) under these conditions were studied, as well as in vivo ectopic bone formation when the BMPs were combined with collagen type I sponges. We show that the effect of these two growth factors is additive and that their combination might be helpful to accelerate in vivo osteogenesis while reducing the amount of each individual BMP used.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
Naturalism and the Inevitability of Fate: Maggie: A Girl of the Streets and Sister Carrie
ABSTRACT The purpose of this essay is to analyze and compare two novels written at the turn of the 20th century that are usually classified as naturalist: Maggie: A Girl of the Streets (1893) by Stephen Crane and Sister Carrie (1900) by Theodore Dreiser. More specifically, I will compare the main characters of each novel (Maggie Johnson and Carrie Meeber), taking into account the deterministic and Social Darwinist ideas that are recurrent in Naturalism. My aim is to call attention to the fact that both heroines have, apparently, very different destinies, although both works were contemporary and are classified within the same literary genre: Maggie dies whereas Carrie succeeds in her acting career. However, the close reading of the texts and the analysis of the narrative voiced used will show that the endings that both authors give to their main protagonists may not be so different after all. El objetivo de este ensayo es analizar y comparar dos novelas escritas a finales del siglo XIX y que suelen enmarcarse dentro del Naturalismo: Maggie: A Girl of the Streets (1893), de Stephen Crane y Sister Carrie, de Theodore Dreiser. Más concretamente, compararĂ© los personajes principales de cada novela (Maggie Johnson y Carrie Meeber), teniendo en cuenta algunas ideologĂas recurrentes en el naturalismo como el determinismo o el darwinismo social. Mi intenciĂłn es resaltar que las dos heroĂnas tienen destinos aparentemente muy distintos (Maggie muere mientras que Carrie se convierte en una actriz famosa), a pesar de que los dos libros son contemporáneos y pertenecen al mismo gĂ©nero literario. Sin embargo, el análisis de los textos y de la voz narrativa muestra que los finales que los autores dan a las protagonistas no son tan diferentes al fin y al cabo
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