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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Effectiveness of Study Strategies: A Comparison of Two Study Methods

Lutes, Kristin E. January 2012 (has links)
No description available.
2

Unga konsumenters kunskaper och beteende inom 3R-principen : med fokus på återvinning och återanvändning av kläder. / Young consumers' knowledge and behavior within the 3R principle : with focus on recycling and reuse of clothing.

Granström, Alicia, Persson, Sofia January 2018 (has links)
Svenskar slänger över 7,5 kg kläder per år i hushållsavfall och 60 procent av dessa plagg är hela och skulle kunna återanvändas. Det nuvarande linjära systemet som utnyttjar jordens resurser och producerar produkter som sedan kasseras, bidrar till bland annat stora mängder avfall och utarmning av naturresurser. Detta är en ohållbar resurshantering. Med den cirkulära ekonomin kan redan använda resurser återanvändas fler gånger istället för att kasseras. Konsumenter visar idag på ett allt större intresse för miljön och hur deras köp kan påverka miljön. Trots detta visar rapporter på att svenskars klädkonsumtion ökar och att unga människor är aktiva konsumenter som sällan tänker på miljön när de handlar. För att skapa en medvetenhet och beteendeförändring krävs kunskap och förståelse. Den cirkulära ekonomin tar inte hänsyn till den bakomliggande orsaken till den ökande resursanvändningen, vilket är människors konsumtionsbeteende. För att kunna övergå till den cirkulära modellen måste man därför undersöka människan och dess roll samt konsumtionsbeteende.   Denna uppsats utgår från den cirkulära ekonomins 3R-princip och konsumtionsbeteende. Syftet med studien är att undersöka unga konsumenters kunskaper och beteende inom 3Rprincipen genom en kvalitativ forskningsmetod. Empirin har samlats in genom åtta djupintervjuer med unga konsumenter i åldern 23-27 år som studerar på universitet eller högskola. Resultatet visar på att unga konsumenter som studerat 3R-principen i sin utbildning har kunskaper inom området, men finner inte dessa tillräckliga för att kunna göra hållbara val. Resultatet visar även på en positiv inställning till återvinning och återanvändning av kläder men inte prioriteten att agera hållbart. Slutsatsen är att unga konsumenter har kunskaper inom 3R-principen men dessa är inte tillräckliga för att ändra sitt konsumtionsbeteendet. Unga konsumenter har även intresse och vilja att agera mer hållbart men inte prioriteten att faktiskt göra det. / Swedes throw over 7.5 kg of clothing a year in the garbage and 60 percent of these garments are whole and could be reused. The current linear system, which exploits the Earth's resources and produces products that are later discarded, contribute to both large amounts of waste and depletion of natural resources. This is an unsustainable resource management. With the circular economy, already used resources can be reused multiple times instead of being discarded. Consumers today show an increasing interest in the environment and how their purchases can affect the environment. Nevertheless, reports show that Sweden's clothing consumption is increasing and that young people are active consumers who rarely think about the environment when shopping. To create awareness and behavioral change requires knowledge and understanding. The circular economy doesn’t take into account the underlying cause of increasing resource use, which is human consumption. Therefore, in order to switch to the circular model, one must examine humans and their role as well as consumption behavior.   This essay is based on the circular economy's 3R principle and consumption behavior. The aim of the study is to investigate young consumers' knowledge and behavior within the 3R principle through a qualitative research method. The empirical material has been collected through eight in-depth interviews with young consumers aged 23-27, studying at university or college. The result shows that young consumers who studied the 3R principle in their education have knowledge in the field, but do not find these sufficient to make sustainable choices. The result also shows a positive attitude towards recycling and reuse of clothing, but not the priority to act sustainable. The conclusion is that young consumers have knowledge within the 3R principle, but these are not enough to change their consumption behavior. Young consumers also have an interest and willingness to act more sustainable, but not the priority to actually do so.
3

Climate Neutral Management : Implement Circular Economy in the Construction Industry / Klimatneutralt Ledarskap : Implementera Cirkulär Ekonomi i Byggbranschen

Weinesson, Linnéa January 2019 (has links)
The construction industry releases a great amount of greenhouse gases to the atmosphere, uses loads of resources and generates a lot of waste. These actions are not sustainable, and the industry has therefore created a roadmap of how to become climate neutral until 2045. A few things highlighted in this roadmap is the importance of management and a shift to circular economy, however, previous research has not covered the connection between these in construction projects. This study aims to understand and assess the influence on management when implementing circular economy in construction industry projects. To fulfill this aim, a theoretical framework was constructed consisting of potential applications of circular economy in construction industry projects. The connection between these applications and project management was thereafter investigated in an empirical study which consisted of a qualitative case study with document reviews, project observations and interviews with different project manager roles of a Swedish construction company. The findings indicate that the implementation influences the managers to focus more on the big picture and think through the choice of methods. Advance planning is essential along with discussing solutions to optimize the use of resource, have good and early communication with the right suppliers and other building sites, and conduct an accurate quantification of approved materials and focus on the handling of these. Additionally, it is vital to do a proper enrollment of new employees and to manage them toward high environmental goals. Lastly, it was found that it is difficult to pinpoint only one manager that gets affected by a specific application since all managers are involved in the implementation of circular economy. / Byggbranschen släpper ut en betydande mängd växthusgaser i atmosfären, använder mycket resurser och genererar mycket avfall. Dessa handlingar är inte hållbara och industrin har därför skapat en färdplan över huruvida de ska bli klimatneutrala till 2045. Några saker som lyfts fram i denna färdplan är vikten av ledarskap och en omställning till cirkulär ekonomi, däremot har befintlig forskning inte berört sambandet mellan dessa i byggprojekt. Denna studie syftar till att förstå och bedöma implementeringen av cirkulär ekonomis påverkan på ledarskapet av byggprojekt. För att uppfylla detta syfte utformades ett teoretiskt ramverk bestående av potentiella tillämpningar av cirkulär ekonomi i byggprojekt. Sambandet mellan dessa tillämpningar och projektledningen undersöktes sedan i en empirisk studie som bestod av en kvalitativ fallstudie med dokumentanalyser, projektobservationer och intervjuer med olika projektledarroller inom ett svenskt byggföretag. Resultaten antyder att implementeringen påverkar ledarna till att fokusera mer på helheten och tänka genom metodvalen. Förskottsplanering är väsentligt samt att diskutera lösningar för att optimera resursanvändningen, ha god och tidig kommunikation med rätt leverantörer och andra byggarbetsplatser, och en noggrann mängdning av godkända material samt fokusera på hanteringen av dessa. Dessutom är det viktigt att göra en ordentlig inskrivning av nyanställda samt att leda dessa mot högt satta miljömål. Slutligen visade resultatet att det är svårt att precisera endast en ledare som påverkas av en specifik tillämpning, eftersom alla är involverade i implementeringen av cirkulär ekonomi.
4

Contribution of tachykinin and kinin receptors in central autonomic control of blood pressure and behavioural activity in hypertensive rats

De Brito Pereira, Helaine 05 1900 (has links)
This work aims at studing the role of tachykinin NK-3 receptor (R) and kinin B1R in central autonomic regulation of blood pressure (BP) and to determine whether the B1R is overexpressed and functional in rat models of hypertension by measuring the effect of a B1R agonist on behavioural activity. Assumptions: (1) NK-3R located in the ventral tegmental area (VTA) modulates the mesolimbic dopaminergic system and has a tonic activity in hypertension; (2) B1R is overexpressed in the brain of hypertensive rats and has a tonic activity, which contributes to hypertension via a dopamine mechanism; (3) the inhibition of NK-3R and B1R with selective antagonists, reduces central dopaminergic hyperactivity and reverses hypertension. A model of genetic hypertension and a model of experimental hypertension were used: spontaneously hypertensive rats (SHR, 16 weeks) and Wistar-Kyoto (WKY) rats infused for 14 days with angiotensin II (Ang II) (200 ng / kg / min, subcutaneous (s.c.) with Alzet mini pump). The age-matched untreated WKY rats served as common controls. In the first study (article # 1), the cardiovascular response in SHR was evaluated following intracebroventricular (i.c.v.) and/or intra-VTA injection of an agonist (senktide) and antagonists (SB222200 and R-820) of NK-3R. These responses have also been characterized using selective dopamine antagonists DA-D1R (SCH23390), DA-D2R (raclopride) or non-selective dopamine DA-D2R (haloperidol). Also the VTA has been destroyed by ibotenic acid. The pressor response induced by senktide and the anti-hypertensive response induced by SB222200 or R-820 were more pronounced by intra-VTA. These responses were prevented by pre-treatment with raclopride and haloperidol. The lesion of the VTA has prevented the pressor response relayed by senktide (i.c.v.) and the anti-hypertensive effect of R-820 (i.c.v.). In addition, SB222200 (intra-VTA) prevented the pressor response of senktide (i.c.v.) and conversely, senktide (i.c.v.) prevented the antihypertensive effect of SB222200 (intra-VTA). The second study (article # 2) showed that the B1R antagonist (SSR240612) administered by gavage or i.c.v. reverses hypertension in both models. This anti-hypertensive effect was prevented by raclopride and haloperidol. In contrast, the two B1R antagonists (R-715 and R-954) injected s.c., which do not cross the blood-brain barrier reduced weakly blood pressure in hypertensive rats. In the third study (article # 3), the i.c.v. injection of a selective kinin B1R agonist Sar[DPhe8][des-Arg9]BK caused behavioural responses in SHR and Ang II-treated rats and had no effect in control WKY rats . The responses elicited by B1R agonist were blocked by an antagonist of NK-1 (RP67580), an antagonist of NMDA glutamate receptor (DL-AP5), an inhibitor of nitric oxide synthase (NOS) (L -NNA) as well as raclopride and SCH23390.The responses were modestly affected by the inhibitor of inducible NOS (iNOS). The B1R mRNA (measured by RT-PCR) was significantly increased in the hypothalamus, the VTA and the nucleus accumbens of hypertensive animals (SHR and treated with Ang II) compared with control rats. These neuropharmacological studies suggest that: (1) the NK-3R from the VTA is involved in the maintenance of hypertension in SHR by increasing DA transmission in the midbrain; (2) the B1R in SHR and Ang II-treated rats contributes to hypertension via a central mechanism involving DA-D2R; (3) the central B1R increases locomotor activity and nocifensive behaviours via the release of substance P (NK-1), DA and nitric oxide in both rat models of hypertension. Thus, the brain tachykinin NK-3R and kinin B1R represent potential therapeutic targets for the treatment of hypertension. The modulation of the mesolimbic/mesocortical dopaminergic pathway by these receptors suggests their involvement in other physiological functions (pleasure, motor activity, coordination of the response to stress) and pathophysiology (anxiety, depression). / Ce travail vise à étudier le rôle du récepteur NK-3 des tachykinines (NK-3R) et du récepteur B1 des kinines (B1R) dans la régulation autonomique centrale de la pression artérielle et de déterminer si le B1R est surexprimé et fonctionnel chez le rat hypertendu en mesurant l’effet d’antagoniste B1R sur l’activité comportementale. Hypothèses: (1) le NK-3R localisé dans l’aire tegmentale ventrale (VTA) module l’activité dopaminergique du système mésolimbique et possède une activité tonique dans l’hypertension; (2) le B1R est surexprimé dans le cerveau du rat hypertendu et possède une activité tonique qui contribue à l’hypertension via un mécanisme dopaminergique; (3) l’inhibition des NK-3R et B1R avec des antagonistes sélectifs réduit l’hyperactivité dopaminergique centrale et renverse l’hypertension. Un modèle d’hypertension génétique et un modèle d’hypertension expérimentale ont été utilisés: le rat spontanément hypertendu (SHR, 16 sem) et le rat Wistar Kyoto (WKY) infusé pendant 14 jours avec l’angiotensine II (Ang II) (200 ng/kg/min, s.c. avec mini pompe Alzet). Le rat WKY non traité du même âge a servi de témoin commun. Dans la première étude (article # 1), la réponse cardiovasculaire des SHR a été évaluée à la suite de l’injection i.c.v. et/ou intra-VTA d’un agoniste (senktide) et d’antagonistes (SB222200 et R-820) du NK-3R. Ces réponses ont aussi été caractérisées en utilisant des antagonistes sélectifs des récepteurs DA-D1R (SCH23390), DA-D2R (raclopride) ou non-sélectif DA-D2R (halopéridol). Aussi le VTA a été détruit par l’acide iboténique. La réponse pressive induite par senktide et la réponse anti-hypertensive induite par SB222200 ou R-820 étaient plus marquées par la voie intra-VTA. Ces réponses ont été prévenues par un pré-traitement avec le raclopride et l’halopéridol. La lésion du VTA a prévenu la réponse pressive relayée par le senktide (i.c.v.) ainsi que l’effet anti-hypertenseur du R-820 (i.c.v.). De plus, le SB222200 (intra-VTA) a prévenu la réponse pressive du senktide (i.c.v.) et inversement, le senktide (i.c.v.) a prévenu l’effet anti-hypertenseur du SB222200 (intra-VTA). La deuxième étude (article # 2) a montré que l’antagoniste du B1R (SSR240612) administré par gavage ou i.c.v. renverse l’hypertension artérielle dans les deux modèles. Cet effet dépresseur a été prévenu par le raclopride ainsi que l’halopéridol. Par contre, le traitement avec deux antagonistes du B1R (R-715 et R-954) qui ne traversent pas la barrière hémo-encéphalique a réduit faiblement la pression artérielle chez les rats hypertendus. Dans la troisième étude (article # 3), l’injection i.c.v. d’un agoniste sélectif du B1R, le Sar[DPhe8][des-Arg9]BK a causé des réponses comportementales typiques chez le SHR et le rat traité à l’Ang II mais il n’a pas eu d’effet chez le rat témoin WKY. Les réponses induites par l’agoniste B1R ont été bloquées par un antagoniste du récepteur NK-1(RP67580), un antagoniste du récepteur NMDA du glutamate (DL-AP5), un inhibiteur des synthétases du monoxyde d’azote (NOS) (L-NNA) ainsi qu’avec le raclopride et le SCH23390. Les réponses ont été modestement influencées par l’inhibiteur de la NOS inductible (iNOS). L’ARNm du B1R (mesuré par RT-PCR) était significativement augmenté dans l’hypothalamus, le VTA et le noyau accumbens des animaux hypertendus (SHR et traités à l’Ang II) comparativement aux rats témoins. Ces études neuropharmacologiques suggèrent : (1) que le NK-3R du VTA est impliqué dans le maintien de l’hypertension chez le SHR en augmentant la transmission DA au niveau du mésenséphale. (2) Le B1R chez le SHR et les rats traités à l’Ang II contribue à l’hypertension artérielle via un mécanisme central impliquant le DA-D2R. (3) le B1R central augmente l’activité locomotrice et les comportements défensifs, via la relâche de substance P (NK-1), de DA et de NO dans un modèle d’hypertension génétique et expérimental chez le rat. Ainsi, les récepteurs cérébraux NK-3 des tachykinines et B1 des kinines représentent des cibles thérapeutiques potentielles pour le traitement de l’hypertension artérielle. La modulation de la voie dopaminergique mésolimbique/mésocorticale par ces récepteurs suggère une participation dans d’autres fonctions physiologiques (plaisir, activité motrice, coordination de la réponse au stress) et en pathophysiologie (anxiété, dépression).
5

Aproximaciones sucesivas de las soluciones de ecuaciones en derivadas parciales de 3r orden

Cascante Dávila, Joaquín Mª 01 January 1960 (has links)
El presente trabajo tuvo su origen durante el transcurso de los estudios monográficos de Doctorado, correspondientes al curso académico 1952-1953 de la Sección de Matemáticas, en que nos fue propuesta en la Asignatura de Doctorado “Ecuaciones en derivadas parciales de tipo hiperbólico”, por el Prof. Dr. Augé, la clasificación y reducción a formas canónicas de las ecuaciones cuasilineales en derivadas parciales de 3er. orden con dos variables independientes. Resuelto este problema, se nos sugirió la posibilidad de obtener un teorema de existencia para las ecuaciones lineales de 3er. Orden con dos variables independientes de tipo hiperbólico, por el método de aproximaciones sucesivas en el campo real, que fuese, por decirlo así, una prolongación de los resultados obtenidos por Picard en las ecuaciones en derivadas parciales de 2º orden. En la actualidad, la teoría de las distribuciones ha contribuído poderosamente a la sistematización de los procedimientos empleados en la resolución de los problemas de contorno adeucados a distintos tipos de ecuaciones diferenciales, dando lugar a los llamados “métodos operacionales”, los cuales constituyen los intrrumentos de cálculo de soluciones de dichas ecuaciones, preferidos por la mayoría de los especialistas a ellos consagrados. Por lo que a nuestro trabajo se refiere, no nos hemos aparato del clásico método constructivo, de la solución en el campo real, mediante aproximaciones sucesivas de la misma, iniciado por Picard y seguido por otros autores, por creer que su eficacia podía extenderse todavía a ecuaciones de orden superior a las estudiadas por Picard, y aún incluso a las por nosotros consideradas. Concretando, el problema que nos hemos planteado y resuelto puede resumirse en los Apartados siguientes: a) Clasificación de las ecuaciones en derivadas parciales de 3er. orden con dos variables independientes y separación de los casos hiperbólicos. b) En los casos hiperbólicos, construcción y cálculo de la solución al problema de Cauchy, por el método de aproximaciones sucesivas en el campo real. c) Teorema de unicidad. d) Generalización a ecuaciones no lineales. De acuerdo con dichas ideas, hemos creído conveniente subdividir nuestro trabajo en cuatro Capítulos para la mejor metodización y exposición del mismo. - En el Capítulo I, hemos clasificado las ecuaciones en derivadas parciales cuasi-lineales de 3er. orden con dos variables independientes, hallando los cambios de variables que permiten reducirlas a las formas canónicas más sencillas separando los casos hiperbólicos de los demás. - En el Capítulo II, planteamos y resolvemos en el campo real al problema de Cauchy para toda ecuación hierbólica determinando los dominios de dependencia de cada punto y prolongación del arco de curva sobre el que son dadas las condiciones iniciales, obteniendo fórmulas resolutivas, demostrativas de que al problema de Cauchy considerado es adecuado a la ecuación dada. - En el Capítulo III, demostramos el teorema de existencia y unicidad para toda ecuación lineal de tipo hiperbólico, reduciada a su forma canónica. - Finalmente, en el IV y último Capítulo, planteamos y resolvemos localmente el problema de Cauchy para toda ecuación cuasi-lineal de 3er. orden de tipo hiperbólico, con dos variables independientes, previamente reducida a su forma canónima, con el mismo sistema de condiciones iniciales que el de las ecuaciones consideradas en los anteriores Capítulos, supuestas verificiadas ciertas condiciones de continuidad y derivabilidad, El método que hemos seguido para la construcción de las soluciones de las ecuaciones en derivadas parciales de 3er. orden con dos variables, de tipo hiperbólico, no se aparta pues, esencialmente, del empleado por Picard y otros en la demostración de los teoremas de existencia de las ecuaciones diferenciales ordinarias de orden cualquiera, y las de derivadas parciales de 2º orden, y la creencia, por parte nuestra, de que el mismo no había agotado todas sus posibilidades, así como de que es todavía de ser susceptible de ser aplicado al cálculo de soluciones en el campo real de ecuaciones de más de dos variables independientes, y de orden superior al tercero, es la principal razón que nos ha impulsado a redactar el presente trabajo
6

Respons på oveckade proteiner : kan plasmid pEGFP-XBPdeldDBD-STOP-tagRFPt användas för detektion av celler vars endoplasmatiska retikulum är stressat? / Unfolded Protein Response : can plasmid pEGFP-XBPdeldDBD-STOP-tagRFPt be used for detection of cells whose endoplasmatic reticulum is stressed?

Wiklund, Magdalena January 2016 (has links)
Bakgrund: Endoplasmatiskt retikulum upprätthåller proteinhomeostasen genom syntes och degradering av proteiner. Tre signalvägar reglerar processen via ”unfolded protein response” på olika sätt. Inositol-requiring enzyme 1 alpha är en signalväg aktiverad av en störd proteinhomeostas. Stressen uppstår om cellen utsätts för kemiska substanser t.ex. i samband med djurförsök vid framtagning av läkemedel. Den aktiverade signalvägens respons leder bl.a. till splicing av X-box-binding Protein 1 mRNA. Syfte: Projektets syfte är att minska behovet av djurförsök genom att möjliggöra ökad implementering av 3R-principen. Frågeställningen är om den fluorescerande plasmiden pEGFP-XBP1∆dDBD-STOP-tagRFPt som binder till X-box binding protein 1 mRNA kan användas för detektion av celler vars endoplasmatiska retikulum är stressat. Metod: Plasmid pEGFP-XBP1∆dDBD-STOP-tagRFPt renades ur DH5-Alpha Escherichia coli med JETstar 2.0 Plasmid Purification Midiprep Kit. Humana epiteliala njurceller 293 transfekterades med plasmiden varpå de doserades med tunicamycin. Kontrollen utgjordes av dimetylsulfoxid. Mikroskopering skedde i fluorescensmikroskopet Zeiss Axiovert 200. Mjukvaran AxioVision Ver. 4.8.1.0. Carl Zeiss Imaging Solutions framställde cellerna på dataskärm. Resultat: Hypotestestets signifians bestämdes till p < 0,05. Resultatet antyder att antalet ER- stressade celler ökar med ökande inkubationstid (p = 0,001 – 0,966). En mindre antydan finns också mot en ökande koncentration av tunicamycin (p = 0,096 – 0,690). Slutsats: En rimlig slutsats kan inte dras då antalet utförda analyser är för få. / Background: Endoplasmic reticulum maintains protein homeostasis by protein synthesis and degradation. Three signal paths regulates the process by ”unfolded protein response” in different ways. Inositol-requiring enzyme 1 alpha is one path activated by a disturbed protein homeostasis. Stress starts if the cell is exposed to chemical substances as in connection with scientific animal experiments when pharmaceuticals are developed. The response of the activated signal path leads e.g. to splicing of X-box-binding protein 1 mRNA. Object: The object of the project is to reduce the need of scientific animal experiments by enabling increased implementation of the 3R principle. The question is if the fluorescent plasmid pEGFP-XBP1∆dDBD-STOP-tagRFPt binding to X-box binding protein 1 mRNA can be used for detection of cells whose endoplasmatic reticulum is stressed. Method: Plasmid pEGFP-XBP1 ∆ dDBD-STOP-tagRFPt was purified from DH5-Alpha Escherichia coli with JETstar 2.0 Plasmid Purification Midiprep Kit. Human epithelial kidney cells 293 were transfected with the plasmid whereupon they were dosed with tunicamycin. The control was made off dimethylsulfoxide. Microscopy was done in the fluorescence microscope Zeiss Axiovert 200. The software AxioVision Ver. 4.8.1.0. Carl Zeiss Imaging Solutions imaged cells on the computer screen. Result: The significans of the hypothesis test was set to p < 0,05. The result suggests that the number of ER-stressed cells increase with increasing incubation time (p = 0,001 – 0,966). A smaller hint is also pointing toward increasing concentrations of tunicamycin (p = 0,096 – 0,690). Conclusion: A reasonable conclusion cannot be made because of too few tests.
7

Contribution of tachykinin and kinin receptors in central autonomic control of blood pressure and behavioural activity in hypertensive rats

De Brito Pereira, Helaine 05 1900 (has links)
No description available.
8

Towards a Circular Economy: An Emerging Economies Context

Patwa, N., Sivarajah, Uthayasankar, Seetharaman, A., Sarkar, S., Maiti, K., Hingorani, K. 23 May 2020 (has links)
Yes / Circular Economy (CE) and the adoption of its principles globally are more important than ever to sustain the rate of production of goods and services to meet the ever-increasing consumer demand that is burdening the environment and society. This study investigates the adoption of CE principles amongst emerging economies as the challenges faced by these economies are generally different in terms of resource availability, varying government policies and consumer behaviour from those of developed economies. This research presents an empirically validated CE adoption model using a sample of 183 consumer responses. The study highlights the strong influence of factors such as consumer behaviour on the acceptance of remanufactured products and using products as a service to encourage the adoption of CE practices in emerging economies. This research offers businesses, consumers and policy makers insights into measures that have been taken by emerging economies that are in line with CE principles.
9

Applications of a humanized Serum-Free cell culture medium in drug ADMET: A Primary Human Hepatocyte and Caco-2 Model Study

Primpas, Lazaros Ilias January 2024 (has links)
This study investigates the efficacy of a newly developed humanized serum-free media (SFM) that replaces Fetal Bovine Serum (FBS), in culturing of common in vitro models (Caco-2 and 3D Primary Human Hepatocytes (PHH)). The research’s focus aligns with the 3R principles (replacement, reduction, refinement) and may potentially lead to enhancing the human relevance of the in vitro models and ultimately contribute to more accurate and successful drug development in the future. This study is divided into two subprojects, Caco-2 and 3D PHH, respectively. For Caco-2, we evaluated cell morphology, proliferation and monolayer formation by assessing the permeability of marker compounds. For PHH, we investigated spheroid formation and viability using an ATP measurement assay, lipid concentration using an Adipored Assay and CYP activity of the 3D PHH. Finally, global proteomics analysis was performed for both Caco-2 cells and 3D PHH grown in SFM and in conventional medium (CM). Our findings show that Caco-2 cells could proliferate well enough in the SFMCaco-2 without any change in their cell morphology, whereas their monolayer tightness was found to be similar in SFMCaco-2 as compared to CMCaco-2. Furthermore, from the proteomics analysis there was no major difference detected between cells in SFMCaco-2 and in CMCaco-2, however several of the relevant drug transporters of this model were found in higher levels in Caco-2 cultured in SFMCaco-2. For 3D PHH, our findings indicate that spheroids could be perfectly formed in both SFM3D PHH and in CM3D PHH, having relatable viability and lipid concentration, especially after two week of culturing period. Finally, the proteomics analysis revealed no significant difference between the proteome of the spheroids when cultured in SFM3D PHH or in CM3D PHH. In conclusion, these results suggest that the SFM provides a viable and sometimes superior alternative to CM for both Caco-2 and 3D PHH, promoting the 3R principles and potentially offering a more human-relevant model for in vitro studies.
10

How circular business models can increase the use of 3R’s - a shift towards circular economy : Case study in Swedish stone material industry

Pedersen, Elsa, Eriksson, Alva January 2022 (has links)
Circular economy (CE) is today gaining a lot of attention, which means to improve resource efficiency through reusing, recycling, and reducing (3R). Increased CE is one step towards improved sustainable development. The aim in this study is to explain how circular economy can pursue sustainable development, by business model innovation. A qualitative study including a market analysis has been performed with 28 semi structured interviews. The context studied was the Swedish stone material industry (SSMI) through NCC and its division Industry, as case company. The participants were employees selected from the case company, competitors, customers, ordering parties, and independent actors.    The study highlights both barriers and opportunities for improving 3R’s on the SSMI. Strict regulations are seen as a strong obstacle whereas reduced climate impact is a great possibility. To contribute successfully to circular economy, a shift towards circular business models (CBM) is needed. Such strategical transformation can be accomplished through business model innovation, which this study shows difficult. A CBM is presented to the case company with for instance customer co-creation and developing new partnerships included. Shaping take-back services are also recommended to be implemented in the CBM. A conclusion is that business models and strategy interrelate, and both concepts are affected by regulations. This imply both positive and negative consequences of the market development, concerning circular economy. Lastly, a conclusion is that the triple bottom line mindset must be improved in the industry to pursue sustainable development. / Cirkulär ekonomi (CE) får idag mycket uppmärksamhet, och det innefattar ökande resurseffektivitet genom återanvändning, återvinning och reducering (3R). Ökning av CE är ett steg i ökad hållbar utveckling. Syftet med denna studie är att förklara hur cirkulär ekonomi kan främja hållbar utveckling, genom affärsmodellsinnovation. En kvalitativ studie har utförts genom en marknadsanalys med 28 semistrukturerade intervjuer. Det studerade sammanhanget var den svenska stenmaterialindustrin (SSMI) och fallföretaget har varit NCC och deras avdelning Industry. Deltagarna var utvalda anställda från fallföretaget, konkurrenter, kunder, beställare och oberoende aktörer.  Studien belyser både hinder och möjligheter för att öka de 3R’n på SSMI. Strikta regler visar sig vara ett starkt hinder medan reducerad klimatpåverkan är en stor möjlighet. För att framgångsrikt bidra till cirkulär ekonomi behövs ett skifte mot en cirkulär affärsmodell (CBM). Sådan strategisk förändring kan åstadkommas genom affärsmodellsinnovation vilket i denna studie har visats sig vara svårt. En CBM presenters till fallföretaget innehållande bland annat samskapande med kund och utveckling av nya partnerskap. Utformande av återtagstjänster är också rekommenderat för implementation i CBM. En slutsats är att affärsmodeller och strategi interagerar och båda koncepten påverkas av regleringar. Det kan medföra både positiva och negativa konsekvenser på marknadsutveckling beträffande cirkulär ekonomi. Slutligen så är en slutsats också att triple bottom line mindset måste förbättras i branschen för att främja hållbar utveckling.

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