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Rostedt, Erica. "The Tween Ghost Story: Articulating the Tween Experience." ScholarWorks@UNO, 2013. http://scholarworks.uno.edu/td/1665.
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In the early 1980s, a particular kind of “tween” (children aged 10-14) ghost story emerged. Through examining multiple examples of tween ghost stories (such as Wait Till Helen Comes by Mary Downing Hahn, Stonewords by Pam Conrad, and Time Windows by Kathryn Reiss), this paper illustrates the ways in which these stories are remarkably consistent in nature, and then investigates this sub-genre’s specific and consistent articulation of the struggle of moving away from childhood and into the teenage years. By using a ghost to create a situation so off balance (a ghost who is stuck, a protagonist who is in flux), the tween ghost story is uniquely and cleverly designed to help the protagonist navigate through the scary situation of growing up.
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Sørenssen, Ingvild Kvale. "Domesticating the Disney Tween Machine : Norwegian Tweens Enacting Age and Everyday Life." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for tverrfaglige kulturstudier, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-27014.
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Disney, parents and children constructing tweens. This thesis explores the age group 9-12 years, called tweens as they are considered to be in-between children and adolescents. The term tweens was first used by marketers to define a consumer group but has trickled into the vocabulary of the mainstream media and the general public. While observing children in two after school programs, references to Disney Channel and more specifically to Hannah Montana and High School Musical frequently appeared. This was the starting point for exploring how different actors - Disney Channel, parents and children - construct this age group. Based on interviews with two representatives from Disney Channel and Disney Consumer Products Nordic, as well as an analysis of Hannah Montana and High School Musical, it became apparent that Disney considers tweens to be aspiring teenagers, as well as being rooted in childhood. Parents of the girls in this study communicated a complex relationship with Disney and the available merchandise. Parents would want to please their children and believed that Disney was a safe choice, simultaneously they expressed scepticism towards the marketing and thought Disney stories were superficial. The main analysis is based on girls and boys aged 9-12. We hear who they think Hannah Montana and High School Musical are made for; the comedy was for both girls and boys, while romance was mostly for girls. The thesis studies the girls' relationship to the merchandise tied to the TV series and films. It finds that having CDs and DVDs was a natural extension of liking the content, but having other products was used to symbolize identity and belonging. Tweens was not a term the children used they spoke of themselves as "middle children." They talked about how in different contexts they would shift between being a child and being more like a teenager. The thesis calls this phenomenon age shifting and considers this to be a main momentum for this age groupDisney, foreldre og barn konstruerer tweens-kategorien. Denne avhandlingen utforsker aldersgruppen 9-12 år, populært kalt tweens da de blir ansett for å være imellom (in-between) barn og ungdom. Begrepet tweens ble først brukt av markedsførere til å definere en konsumentgruppe, men brukes i dag blant annet i media når man omtaler barn i denne aldersgruppen. Under observasjon av barn i to skolefritidsordninger dukket det stadig opp referanser til Disney Channel, og mer spesifikt til Hannah Montana og High School Musical. Det var utgangspunktet for å utforske hvordan forskjellige aktører - Disney Channel, foreldre og barn - konstruerer denne aldersgruppen. Basert på intervju med to representanter fra Disney Channel og Disney Consumer Products Nordic, samt en analyse av Hannah Montana og High School Musical, kom det fram at Disney anser at tweens strekker seg mot tenåringer, men at de fortsatt er forankret i barndommen. Foreldrene til jentene i avhandlingen kommuniserte en kompleks relasjon til Disney og de tilknyttede produktene. Foreldrene ville gjerne glede barna sine og mente at Disney var et trygt valg, samtidig utrykte de en skepsis til all markedsføringen og syntes Disney-historiene var overfladiske. Hovedanalysen baserer seg på jenter og gutter i alderen 9-12. Vi får høre hvem de mener Hannah Montana og High School Musical er laget for, at komedie var for både jenter og gutter, mens romantikk var mest for jenter. Avhandlingen studerer jentenes forhold til produktene man får kjøpt knyttet til TV-seriene og filmene. Den finner at det å ha CDer og DVDer var en naturlig forlengelse av å like innholdet, men det å ha andre produkter ble brukt for å symbolisere identitet og tilhørighet. Tweens var ikke et begrep barna brukte om seg selv, de omtalte seg som «mellombarn». De fortalte om hvordan de i forskjellige sammenhenger vekslet mellom å være barn og å være mer som ungdommer. Avhandlingen kaller dette fenomenet aldersveksling og anser det som en sentral karakteristikk for denne aldersgruppen
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Hamer, Naomi Elana. "Reading tween franchises : cross-media practices and the discourses of tween girlhood." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/10007385/.
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The 'tween' age group, particularly preadolescent females between the ages of 8 and 12, constitutes a heavily targeted niche for the branding and cross marketing of products. Consequently, books aimed at tween readers are often part of cross-media franchises that may include film and television adaptations, affiliated music albums, online fan clubs, video games, clothing, and cosmetics. In this context, representations may be adapted across a number of media forms, and conversely, responses to texts may be facilitated by engagement with diverse media. In light of these trends, this research explores how intersecting discourses of tween girlhood are negotiated through crossmedia practices by both producers and consumers of tween franchises. The thesis begins with a review of research from the fields of children's literature criticism, cultural and media studies, girlhood studies, and New Literacies. Building on this review, I outline a theoretical and methodological frame rooted in theories of discourse as articulated through multimodal design and cross-media play. The analysis traces a cultural history of key discourses in Anglo-American texts for and about preadolescent girls. In the following chapters, two tween-oriented cross-media worlds, The Chronicles ofNarnia and Mary-Kate and Ashley Olsen, are used as case studies to examine the roles of multi modal design and cross-media play in the articulation of these discourses of tween girlhood. Each case study addresses the design of franchise texts (i.e. books, DVDs, tie-in texts); fan cultures related to these texts; and the responses of eightyear- old participants during fieldwork in Toronto, Canada. The conclusion of this thesis discusses the potential application of this doctoral study in future research on crossmedia texts and practices.
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Hein, Jill Marissa. "Tween Body Image and Related Clothing Preferences." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1392105358.
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Tomari, Yukako, and yukakotomari@hotmail com. "Investigation the tween girls fashion market in Melbourne: Opportunities for expansion and adaptation." RMIT University. Architecture & Design, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20090317.141901.
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In the last decade, children who are in the age range between childhood and adolescence, the so called 'tweens', have captured the attention and a great deal of interest of marketers and many commercial stakeholders in different fields of business due to their significant spending power and specific culture. Tweens are now much more strongly targeted by marketers and businesses than were the previous generation; girls in particularly are targeted more than boys. Within a fashion context, tween girls are expanding their influence and their consumer power in the market. Following the global acknowledgement of tweens, in Australia, and in Melbourne in particular, tween fashion retailers have been emerging and evolving recently in response to the market's interest and demand for tween fashion. The tween girls' fashion consumption has a viability and is seen a major emergent marketing phenomenon one that is predicted to expand. There is currently a debate in Australia whether tween girls dress inappropriately as adults. This may be a result of the absence of a particular tween girls fashion sector in fashion industry in Melbourne. Further development will be significant in providing age-appropriate clothing range for the market. In order to achieve this, it is necessary to investigate the market segment. A case study of a Japanese company is used to gain further understanding of current and future developments within the market. The case study will provide some background information to the situation being presented and assist in the analysis of possible suggestions and recommendations. The tween girls fashion industry incorporates many different factors. There is a specific focus on the opportunities for expansion and adaptation in the market segment. This research investigates the tween girls' fashion segment in Australia to identify and understand its relationship with respect to fashion marketing and consumption. It also identifies the gaps or opportunities in the market and proposes business opportunities to address these gaps. This research demonstrates the possibility for the market development of tween girls in Melbourne.
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Guthrie, Meredith Rae. "SOMEWHERE IN-BETWEEN: TWEEN QUEENS AND THE MARKETING MACHINE." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1119390228.
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Riley, Rosemary McKeon. "The Tween Queens: Little girls and big girl relationships." Diss., Connect to online resource, 2005. http://wwwlib.umi.com/cr/colorado/fullcit?p1425765.
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Preté, Paulo Sérgio Castilho. "Solubilização de membranas de eritrocitos por surfactantes da serie Tween." [s.n.], 2000. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314158.
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Orientador: Eneida de PaulaDissertação (mestrado) - Unversidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-07-26T18:12:47Z (GMT). No. of bitstreams: 1 Prete_PauloSergioCastilho_M.pdf: 7512602 bytes, checksum: 3cde985a4e814dabb7fb0d50b30a4d23 (MD5) Previous issue date: 2000
Resumo: Surfactantes apresentam efeito concentração dependente sobre membranas de eritrócitos, podendo proteger ou solubilizar essas membranas. Neste trabalho estudamos a interação de surfactantes não-iônicos da série Tween (Polioxietileno-sorbitol) com membranas de eritrócitos humanos. Triton X1O0 (t-octilfenoxi polietoxi etanol), foi usado como controle para os ensaios hemolíticos. Inicialmente fizemos a carActerização físico-auímicA dos surfActAntes atrAvés da determinAção da CMC, e medidAs de lH-RMN, que comprovaram a purezA e composição estruturAI dos surfactantes. Estudos hemolíticos em eritrócitos humAnos (com suspensões de Ht de 5 20%) revelaram que os surfactantes da série Tween (20, 40 e 80) têm efeito protetor e lítico Acima dAS suas respectivAs CMCs (59, 27 e 12 _), enquAnto que com o Triton Xloo estes efeitos ocorrem na faixa dA sua concentrAção micelar críticA (0,25 mM). O ensaio de proteção a hemólise foi feito em condições hipotônicAs (77 mM de NaCI) e o de lise em condições isotônicas. Em Ambos ensAios mediu-se fotometricamente A saída de hemoglobina (Hb), do eritrócito. DAS concentrAções de surfActAnte parA proteção (Cprot), início (csat) e 100% de hemólise (CSOI) determinamos AS razões molares surfActante:lipídio no eritrócito para proteção e lise (RProt, Rsat, Rso respectivamente). Nos ensaios em condições isotônicas medimos também a liberação do I( intracelular (por potenciometria) como um método alternativo de quantificar a hemólise. Assim como as medidas de liberação de Hb, os ensaios de liberação de I( mostraram-se adequados aos estudos hemolíticos. Detectou-se uma estreita correlação entre os valores de csat e esol obtidos pelas duas técnicas, embora a liberação de I( ocorra em concentrações menores de surfactante, indicando que a saída de I( precede a de Hb, na hemólise. Em concentrações muito altas esses surfactantes podem induzir a oxidação da Hb, sendo que o Tween 80 tem maior poder oxidante que os demais da série (Tween 80 > Tween 40 > Tween 20) e o Triton X100 não oxida a Hb. O efeito oxidante do Tween 80 impediu a determinação dos valores de Rso1 em Ht mais altos. O tratamento proposto por Lichtenberg (1985) para a quantificação da razão efetiva surfactante:membrana para solubilização não se mostrou adequado à análise do efeito hemolítico dos surfactantes da série Tween, cujos valores de R são muito altos, caracterizando-os como pouco hemolíticos
Abstract: Surfactants present hemolytic effects and depending on their concentration, they can either protect or solubilize erythrocyte membrane. In this work we have studied the interaction of nonionic surfactants from the Tween series (polyoxyethylenesorbitan) with human erythrocytes membranes. Triton Xl00 (t-octylphenoxypolyethoxyethanol) was used as a control, in hemolytic assays. To assure the purity and structural composition of the surfactants we employed CMC determination and lH-NMR characterization. Hemolytic studies with human erythrocytes (Ht 5 - 20%) showed that surfactants from the Tween series (20,40 and 80) have a protective and Iytic effect upon the membrane above their respective CMCs (59, 27 and 12 _), while Triton Xl00 presents those effects at its CMC range (0,25 mM). The "protection" assays were carried out in a hypotonic media (NaCI 77mM) and the Iysis experiments in isotonic conditions. In both assays Hb release from the erythrocyte was spectrophometrically measured. From the surfactant concentrations for protection (Ol'Ot), onset (csat) and 100% hemolysis (csol) we determined the surfactant:lipid molar ratios for protection and Iysis (RProt, Rsat, R$OI respectively). At isotonic condition we measured also the release of intracelular K'" (by potenciometry) as an alternative method for quantifying hemolysis. As well as Hb release measurements, the assays of K'"-release showed to be quite adequate for the study of hemolysis. There is a good correlation between csat and csol values obtained by the two techniques, although K'"-release occurs at lower surfactant concentrations than Hb-release. In extremely high concentrations, these surfactants induce Hb oxidation, being Tween 80 the one with the highest oxidative power, in comparison to the other Tweens (Tween 80 > Tween 40 > Tween 20). Triton X100 does not oxidise Hb. The oxidative effect of Tween 80 prevented the determination of Rso1 values in the highest Hts. The treatment proposed by Lichtenberg (1985) for the quantification of surfactant:membran ratios for solubilization was not found adequate for the analysis of the hemolytic effect of Tweens, which R values are very high, characterizing them as weak solubilizers
Mestrado
Bioquimica
Mestre em Biologia Funcional e Molecular
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Sancheti, Yukti Kamal Singh Ulrich Pamela V. Connell Lenda Jo. "Understanding tween girls' self perception and clothing behavior a conceptual framework /." Auburn, Ala, 2009. http://hdl.handle.net/10415/1749.
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Kennedy, Melanie. "Bratz, BFFs, princesses and popstars : femininity and celebrity in tween popular culture." Thesis, University of East Anglia, 2012. https://ueaeprints.uea.ac.uk/45684/.
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The last decade has seen a dramatic increase in media output aimed at “tweens” (preadolescent girls), and the expansion more broadly of tween popular culture. This exclusively female preadolescent consumer demographic is seen to emerge alongside a heightened visibility of girls within popular culture since the mid-1990s, and continuing anxieties about girlhood in this intensely mediated environment. However, this burgeoning field has yet to be matched in academic attention. This thesis offers a timely examination of mainstream tween films, television programmes, celebrities and extra-texts from 2004 onwards, including “princess” narratives The Prince & Me (2004, 2006, 2008, 2010) and A Cinderella Story (2004, 2008, 2011), and Disney Channel programming and Original Movies, Hannah Montana (2006-2011) and Camp Rock (2008, 2010). It forges a dialogue between postfeminism, film and television, celebrity, and the figure of the tween, in order to examine how the tween is both constructed and addressed by the films and television programmes that make up tween popular culture. Tweenhood is a discursive construction emerging in the mid-1990s and coming to cultural prominence in the early twenty-first century. The tween is understood to be defined by her transitional status, her “becoming”-woman; as such, the texts that make up tween popular culture can be seen to guide the tween in her development of an “appropriately” feminine and (post)feminist identity through a rhetoric of “choice”. Such identities are predicated on revealing and maintaining an “authentic” self. The need to develop an “appropriately” feminine and (post) feminist identity whilst remaining “authentic” requires the tween to be the ideal selfsurveilling, transforming subject of neoliberalism. Celebrity plays a central role in tween popular culture, articulating the parallels between “becoming”-woman and “becoming”-celebrity. Through a combination of textual analysis, and broader discursive and contextual analysis, this thesis highlights the centrality of femininity and celebrity to the tween as a figure constructed by the texts that make up tween popular culture. It analyses the ideal tween consumer as projected by the texts. This thesis draws attention to the culturally and academically devalued subject of the construction of tweenhood within a gendered, age-specific popular culture.
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Su, Lijin. "Peer Victimizationand SubjectiveHealth-Acomparisonbe- tween students with and without disabilities in Sweden." Thesis, Jönköping University, HLK, CHILD, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-51706.
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Bullying can have a negative impact on children’s development andmental health. Studentswith disabilities aremore likely to be targeted for bullying than studentswithout disabilities. In particu- lar, studies have shown that studentswith disabilities are at greater risk of bullying than students without disabilities. In addition, childrenwithdisabilities have higher riskof lowsubjective health. Results showed that therewere significant differences in the dependent variables among four dif- ferent groups of bullying participants (disabled victims, victimswithout disabilities, non victims with disabilitiesandnon-victimswithoutdisabilities).Non-disabledstudentswhowere not bullied had the highest level of subjective health,while the subjective health of disabled students who are not bullied is higher than that of disabled students who are bullied and non-disabled students who are bullied. Thismeans that as the risk of exposure to bullying increases, the subjective health of childrenwith disabilitieswillbefurther lower.Childrenwithdisabilities alone have higher life satisfaction than those with disabilities who and bullied and have higher life satisfaction than those bullied without disabilities. And childrenwithdisabilities aremore likely to report somatic and psychological symptoms than childrenwithout disabilities.Children who were bullied reportedmore somatic symptoms than childrenwho were not bullied. Therefore, schools should establish student violence prevention interventions to reduce peer victimization regardless of students’ disabilities.
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Gutteridge, Isobel Charlotte. "Becoming stardolls : untangling postfeminist and romantic childhood (re)positionings in tween girlhood." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/77130/.
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This thesis analyses the construction and negotiation of ‘the tween’ and tween cultural spaces online, forming part of an emerging field of digital girlhood studies. The research is situated in two online ‘tween’ spaces: Stardoll, a commercial website, and The Ugly Side of Stardoll, a blog run by members of Stardoll. Combining a ‘cultural analysis’ approach with ethnographic traditions such as ‘immersion’ and ‘mapping’, this thesis interrogates articulations of tween culture through interlinking online case studies. The key findings of this thesis are centred on three themes. First, the construction of an explicitly tween culture on Stardoll that situates the site within a commodified pinkification of girl culture. Second, the governance of boundaries of tween girlhood, examined through two features of the site. (1) I argue that the production of Cyrus as a tween celebrity, by Stardoll and the girls’ who consume her, are moderated within a 'tween speech’ genre; and (2) interrogating discourses of risk I argue that the boundaries of Stardoll’s tween culture are governed by understandings of risk within the site and from the girls’ blog The Ugly Side of Stardoll. The third theme is the articulation of tween femininity; I argue that Stardoll produces a neoliberal, postfeminist tween identity on the site. Interestingly, the girls who use Stardoll (re)position other, younger girls within Romantic discourses of childhood in their governance of tween girlhood. However both Stardoll and the girls are invested in similar constructions of tween girlhood based on ‘wholesomeness’ and framed by understandings of age, through complex discourses of postfeminism and Romantic childhood.
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Shmidt, Melinda Sue. "Preferences Among Tween Girls: Market Research and Customer Satisfaction Data for Fashion Retailers." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1420209355.
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Calabro, Angelina Louise Ulrich Pamela V. Connell Lenda Jo. "Analysis of pant pattern shapes for tween girls based on 3D body scans." Auburn, Ala, 2008. http://hdl.handle.net/10415/1515.
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Koutsogianopoulos, Ralia. "Thonging for identity : learning about girlhood, sexuality and feminity in a tween retail space." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=83190.
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Children learn from a variety of sources. One of the most powerful pedagogical sites for kids is the consumer sphere. Marketers recognize this and have recently carved out a new consumer niche for those between childhood and adolescence, marking them as tweens. La Senza Corporation, which specializes in women's lingerie, responded to this trend by opening a tween store with a name heavily laden with meanings of sexuality: La Senza Girl. This study will apply a textual analysis to the tween retail space, in an effort to understand the informal pedagogy that takes place within this milieu. While La Senza Girl celebrates girlhood by creating a space that tween girls can call their own, it is important to take stock of the meanings of girlhood being celebrated. This study interrogates La Senza Girl's 'pedagogies' of femininity, sexuality and girlhood.
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Liu, Fuzhen. "Remediation of soil contaminated by organic pollutants using Tween 80 and electrochemical advanced oxidation processes." Thesis, Paris Est, 2020. http://www.theses.fr/2020PESC2055.
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Sous la direction du professeur Mehmet Oturan et du professeur Hui Zhang, j’ai fini toutes les parties des thèses. Un article a été publié dans SCI et les autres parties sont prêtes à se soumettre à la revue. Maintenant, je modifie les papiers et les thèses. Les difficultés sont la détection des contaminants parce qu’il a besoin de la machine de fluorescence et de la méthode d’extraction complexeSoil contaminated by petroleum-hydrocarbons is a serious environmental problem since it is toxic to agriculture and human. And the polycyclic aromatic hydrocarbons (PAHs) in petroleum-hydrocarbons possess carcinogenicity, teratogenicity, mutagenicity, low volatility and poor solubility properties. Moreover, PAHs are persistent in soil and difficult to be degraded. Hence, effective methods are essential to remedy soil contaminated by petroleum-hydrocarbons and particularly the PAHs. Among various remediation methods, soil washing (SW) combined with surfactant is a promising techniques since it is an economical and effective approach. This technology promotes the transformation of contaminants from soil to aqueous solution, which is especially applied for heavily contaminated soil. However, a soil washing solution highly loaded with surfactant and contaminants is produced. Therefore, effective treatment of soil washing solution is a challenge for promoting the application of surfactants and the remediation of contaminated soil. The combination of soil washing process and electrochemical advanced oxidation processes (EAOPs) constitutes an effective technique for the treatment of soil washing solution. In this paper, Tween 80 was applied as surfactant during soil washing process. The lipophilic part of Tween 80 tends to contaminants or soil particles and the hydrophilic part has tendency to the aqueous phase. Thus, Tween 80 promotes the transformation of hydrophobic organic contaminants from soil to aqueous phase. Then the soil washing solution highly loaded with contaminants and surfactant was treated by EAOPs, processes based on the generation of strong oxidant species such as hydroxyl radicals (•OH), sulfate radicals (SO4•−) and active chlorine (•Cl), are one of the most efficient methods for degrading refractory organic pollutants in soil washing solution. The effect of EAOPs including electro-oxidation (EO), electro-Fenton (EF), sulfate radical-based advanced oxidation processes (AOPs) was investigated in the degradation of petroleum-hydrocarbons. Besides, a potential advanced oxidation process including the presence of chlorine s was applied for treating soil washing solution which contains polycyclic aromatic hydrocarbons (PAHs) and Tween 80
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McInnis, Jeffrey A. "Biodegradation and Dewatering of an Industrial Waste Oil." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/41440.
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Waste oil generated from industrial operations at a diesel locomotive maintenance facility was investigated to establish its treatability and potential volume reduction. The waste oil and water mixture separated into four distinct layers; free oil, emulsified oil, weathered oil, and wastewater. The research was conducted in a series of three batch experiments and focused on the emulsified and weathered oils. The waste oil was aerobically treated in nutrient amended, 55 gallon (208 L) drums for 38 to 42 days in 10 and 20 % mixtures with sufficient air for mixing and oxygen. Biodegradation, and the role of a synthetic surfactant in promoting biodegradation, was measured using chemical oxygen demand (COD), fluorescein diacetate (FDA), and gas chromatography (GC) analyses with extractable material. Dewatering of biodegraded oil was measured using capillary suction test (CST), time to filter (TTF), and percent cake solids.
Batch 1 examined the role of bioaugmentation by comparing a 10% waste oil mixture that was augmented with a mixture of hydrocarbon degraders to a 10 % mixture of waste oil with no bioaugmentation. Final COD reductions were 59 (± 9) and 38 (±3) % for the bioaugmented and non-bioaugmented reactors, respectively. Chromatographs showed significant reduction in the abundance of peaks by the end of the experiment for both reactors. Overall results suggested that there was no significant difference in biodegradation capabilities between the amended and native microorganisms.
Batch 2 was conducted to determine if a synthetic surfactant (Tween-80) could enhance biodegradation of a 10 % waste oil mixture. The surfactant-amended reactor showed COD reduction 3 days before the non-surfactant-amended reactor. Chromatographs showed similar results for both reactors with the non-surfactant-amended reactor showing slightly better degradation by the end of the experiment. The total COD reduction by the end of the experiment was the same in both (R1: 85 ± 20%, R2: 84 ± 16 %), suggesting that exogenous surfactant addition did not have a long-term impact in the biodegradation of the waste oil.
Batch 3 examined the effect of different oil phases and concentrations on biodegradation and the dewatering characteristics of post-biodegraded waste oil. The 20 % weathered and emulsified waste oil mixture showed a clear delay in COD reduction (no notable reduction until day 24) compared to the 10 % weathered waste oil mixture. The final COD reductions were the same (R1: 48 ± 13%, R2: 49, ± 23 %). Chromatographs showed similar results for both reactors and indicated that degradation of the waste oil occurred in both reactors. The data suggest that the 20 % waste oil mixture can be degraded to the same extent as the 10 % mixture in 38 days.
Dewatering characteristics, as measured by CST, were poor for the 20 % post-biodegraded combined waste oil mixture without conditioning. Conditioning with alum or ferric chloride substantially improved dewatering of the waste oil for the 20 % mixture but was of limited benefit for the 10 % mixture. Percent cake solids for conditioned 10 % post-biodegraded waste oil mixture was 44 (± 0.3) to 50 (± 1.7) % and 34 (± 0.3) to 50 (± 1.8) % for the 20 % mixture. The cake solids for the unconditioned 10 % mixture was 50 to 65 % and 54 to 68 % for the 20 % mixture. The higher percent cake solids for the unconditioned 20 % mixture was countered by the very high TTF (up to 30 min. to filter 50 mL) and the inability to dewater the sludge during the last five sampling events. Conditioning appeared to have a limited effect on the dewatering properties of the 10 % mixture.Master of Science
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Hunzicker, Gretel Mara. "Biotechnological and physiological relevance of the detergent Tween 20 as a novel inducer of higher plant promoters." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=980096499.
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Clark, Lorie Jane. "Innocence Lost? The early sexualisation of tween girls in and by the media: An examination of fashion." Thesis, University of Canterbury. Political Science and Communication, 2008. http://hdl.handle.net/10092/1898.
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The relationship between the mass media and children is historically fraught, characterised by a concern for the potential effects on the leaders of the future. This thesis addresses the role of the media (particularly magazines) with regard to ideas of sexualisation, examining fashion clothing and identity in relation to tween girls aged between eight and 12-years-old. The impact of mass media is undeniable, and vital to a discussion of modern sexualisation of girls, as Huston, Wartella and Donnerstein maintain there are “strong theoretical reasons to believe that media play an especially important role in the socialisation of sexual knowledge, attitudes and behaviour” (1998: 12).
Surveys were conducted with a total of 168 tween boys and girls, and focus groups with 28 girls in this age bracket in New Zealand, to explore the roles of fashion, media and sexualisation in the lives of young people growing up at a time of unprecedented consumerism and media exposure. The results found that parents still have great influence in the clothing choices of their tween, though they are shown to move progressively towards independence and autonomy as they approach adolescence. When looking at advertising images and fashion in magazines, these girls showed clear signs of age aspiration and an intense dislike for anything remotely ‘kiddy’.
Whilst the examination of sexualisation had to be conducted on an implicit level, many girls commented explicitly about the degree of sexuality in some images, their dislike for such characterisations waning over time. As the goal of the mass media and advertising is to turn people into consumers, even commodities themselves, this research contributes to a growing discourse around the need for children to be protected and taught to engage critically with media texts to prevent sexualisation, commodification and exploitation from drowning out the tweens’ unique voice.
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Ramos, Ligia da Silva. "Interação de detergentes não-ionicos coma membrana eritrocitaria : estudo sobre a ação dos detergentes da serie tween." [s.n.], 1991. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314585.
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Orientador : Nilce Correa MeirellesDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Neste trabalho foram detectados aspectos físico químicos da interação dos detergentes não-iônicos polioxietileno-sorbitol (Tween 20, 40, 60, 80) com a membrana eritrocitária através da utilização das técnicas de RPE e difração de raios-X. Os compostos testados apresentaram um comportamento bifásico em relação à promoção da hemólise hipoosmótica dependente da concentração em que são utilizados. Foram observadas alterações morfológicas nos eritrócitos tratados com os detergentes detectando-se a presença de formas crenadas e "cup-form". Os espectros de RPE do marcador 5-SASL analisados em função da razão detergente:lipídio mostraram que quando esta razão era pequena (e em termos do processo hemolítico havia um efeito de diminuição dessa taxa) nenhum efeito na estrutura da membrana foi observado. A medida que essa razão aumenta. há a formação de agregados polidispersos (detergente-lipídio) e a promoção da hemólise. Tais efeitos mostram ser dependentes da razão detergente:lipídio e não da presença do detergente na sua forma micelar. Os padrões da difração de raios-X obtidos mostraram que o detergente não afeta a ordem da membrana nem produz separação de fase quando protege a célula do "stress" hipoosmótico havendo indicações da ocorrência de mudanças estruturais apenas
Abstract: Here we present EPR and X-ray diffraction studies of the interaction of non-ionic polyoxyethylene-sorbitan derived detergents (Tween 20, 40, 60, 80) on rat erythrocytes regarding to its physical-chemical aspects. The compounds showed a biphasic behaviour in relation to the promotion hemolysis depending on their concentration. Changes in the morphological cell patterns were observed in detergent-treated erythrocytes and typical crenated and cup form erythrocytes were detected. The EPR spectra of a spin labeled stearic acid (5-SASL) were analyzed as a funtion of the detergent: lipid (D/L) ratio. At low D/L ratio protection against hipoosmotic lysis was observed and no major effect on membrane structure was detected. Increasing D/L ratios give rise to increasing amounts of polydisperse (mixed) aggregates. Indicating that the effects depend on the D/L ratio, rather than on the presence of micelar detergent. X-ray diffraction patterns obtained for detergent treated ghosts at hemolysis-protective concentration showed that the detergent presence does not affect the membrane order neither leads to phase separation. The results are indicative of structural changes only
Mestrado
Mestre em Ciências Biológicas
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Manuel, Melissa Barnes Ulrich Pamela V. Connell Lenda Jo. "Using 3D body scan measurement data and body shape assessment to build anthropometric profiles of tween girls." Auburn, Ala, 2009. http://hdl.handle.net/10415/1585.
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Silva, Cassiano Correa da. "Otimização da produção de botriosferana por Botryosphaeria rhodina na presença de óleo de soja e tween 80." Universidade Estadual de Londrina. Centro de Ciências Exatas. Programa de Pós-Graduação em Biotecnologia, 2007. http://www.bibliotecadigital.uel.br/document/?code=vtls000120318.
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Neste trabalho foram avaliados o efeito da adição de óleo de soja, óleo de babaçu, etanol e Tween 80 na produção de botriosferana, um exopolissacarídeo (EPS) do tipo ß-(1,3)(1,6)-D-glucana, secretado no meio de cultivo pelo fungo ascomiceto Botryosphaeria rhodina. Também foi otimizada a produção desta ß-glucana utilizando a abordagem fatorial, após triagem prévia das variáveis que mais influenciaram na sua produção. A adição de óleo vegetal aumentou a produção do EPS, enquanto que a de etanol não promoveu diferença significativa na produção. O tempo e o pH inicial de cultivo, as concentrações de glucose, óleo de soja e de Tween 80 foram as variáveis que demonstraram efeito significativo na produção de botriosferana. A condição otimizada para a produção do EPS foi glucose 40 g/L, óleo de soja 10 mL/L, Tween 80 4,5 g/L, durante 72 horas a 180 rpm, 28 °C, pH inicial 5,7 com 7 mL de inóculo para cada 100 mL de meio de cultivo, na condição estabelecida. A produção de botriosferana prevista pelo modelo matemático foi 8,22 ± 1,36 g/L, enquanto que a produção obtida na validação experimental foi 7,74 ± 0,13 g/L, confirmando o resultado previsto. A caracterização parcial de botriosferana produzida na condição otimizada mostrou que o óleo de soja e Tween 80 não afetaram as características estruturais da molécula do EPS.The effects of the addition of soya bean oil, babassu oil, ethanol and Tween 80 on the production of botryosphaeran, a ß-(1,3)(1,6)-D-glucan exopolysaccharide (EPS) secreted by the ascomycetous fungus Botryosphaeria rhodina, were evaluated in this work. Production of this ß-glucan was also optimised using the factorial approach, following initial screening for variables that most markedly influenced botryosphaeran production. The addition of vegetable oil enhanced EPS production, whereas ethanol had no significant effect on production of this ß-glucan. The variables initial pH and growth time, as well as glucose, soya bean oil and Tween 80 concentrations showed significant effect on botryosphaeran production. Optimised conditions for production of this EPS was 40 g/L glucose, 10 mL/L soya bean oil, 4,5 g/L Tween 80, during 72 hours and 180 rpm shaking rate, at 28 °C, intial pH 5,7 and 7 mL of inoculum for each 100 mL of culture media, under standard conditions previously stablished. Botryosphaeran production predicted by the fitted model was 8.22 ± 1.36 g/L, whereas production observed in experimental validation was 7.74 ± 0.13 g/L, which is in agreement with predicted values. Partial characterisation of botryosphaeran produced under optimal conditions showed that the use of soya bean oil and Tween 80 did not affect structural features of the molecule.
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Graça, José Perez da [UNESP]. "cis-Jasmone e Tween 20 na indução de metabólitos secundários em soja e seus efeitos em insetos-praga." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/102810.
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A pulverização com os tratamentos água; água + Tween 20; e água + Tween 20 + cis-Jasmone nos genótipos BRS 134, IAC 100 e Dowling afetaram negativamente o peso de insetos-praga da soja. Plantas de soja pulverizadas no estádio R6 com os tratamentos foram utilizadas para avaliar o efeito do cis-Jasmone sobre ganho de peso do percevejo-marrom, Euschistus heros. Plantas da cultivar Dowling tratadas com cis-Jasmone reduziram significativamente o peso do percevejo. A aplicação do cis-Jasmone também provocou a produção de isoflavonoides nas vagens e nos grãos. Nas vagens foi observado o aumento das formas glicosídicas (daidzina e genistina) e das malonís (daidzina e genistina), assim como das agliconas (daidzeína, gliciteína e genisteína). No grão, observou-se o aumento das concentrações de daidzeína e malonil genistina. Plantas dos mesmos genótipos no estádio V3, foram pulverizadas com os mesmos tratamentos. As folhas de plantas tratadas com Tween 20 e cis-Jasmone reduziram o peso de Anticarsia gemmatalis tanto na cultivar IAC 100 como Dowling. A produção de isoflavonóides nas folhas foi afetada pela aplicação do Tween 20 e cis-Jasmone, aumentando a concentração da malonil (daidzina, glicitina e genistina) e da aglicona daidzeína. Pelas análises foi observado aumento da concentração da fitoalexina coumestrol nas plantas tradadas com Tween 20 e cisJasmone. A influência negativa no peso dos insetos e aumento da concentração dos isoflavonóides sugere que o Tween 20 e o cis-Jasmone tem papel importante na indução da rota dos fenilpropanoides e que estes compostos afetam o desenvolvimento de insetos-praga
The spray treatments water; water + Tween 20; and water + Tween 20 + cis-Jasmone in the genotypes BRS 134, IAC 100 and Dowling had negative effects on the weight of insect-pests of soybean. Soybean plants sprayed with treatments at R6 stage were used to evaluate the effect of cis-Jasmone on the weight gain of brown stinkbug, Euschistus heros. Plants of Dowling treated with cis-Jasmone significantly reduced the weight of the stink-bug. The application of cis-Jasmone also triggered the production of isoflavonoids in soybean pods and grains. In the pods, it was observed increasing in the glycosidic (daidzin and genistina), and the malonyl (daidzin and genistin), as well as the aglycone (daidzein, glycitein and genistein) forms. In the grain isoflavonoids daidzein and malonyl genistein concentrations increased. Plants of the same genotypes at V3 stage were sprayed with the same treatments. Leaf plants treated with Tween 20 and cis-Jasmone reduced the weight of Anticarsia gemmatalis in the cultivar IAC 100 and Dowling. The production of isoflavonoids in leaves was affected by Tween 20 and cisJasmone sprayings, increasing the concentration of malonyl (daidzin, genistin and glycitin) and aglycone daidzein. By these analyzes, it was observed increasing in phytoalexin coumestrol concentration in plants treated with Tween 20 and cis-Jasmone. The negative influence on the weight of insects and on the increase of isoflavonoid concentrations suggests that the Tween 20 and cis-Jasmone plays an important role in inducing pathway of phenylpropanoids and that these compounds affect development of insect-pests
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Graça, José Perez da. "cis-Jasmone e Tween 20 na indução de metabólitos secundários em soja e seus efeitos em insetos-praga /." Jaboticabal, 2012. http://hdl.handle.net/11449/102810.
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Orientador: Sônia Marli ZingarettiCoorientador: Clara Beatriz Hoffmann Campo
Banca: Lizandra Lucy Catelli
Banca: Maria Cristina Neves de Oliveira
Banca: Sandra Helena Unêda Trevisoli
Banca: Janete Aparecida Desidério
Resumo: A pulverização com os tratamentos água; água + Tween 20; e água + Tween 20 + cis-Jasmone nos genótipos BRS 134, IAC 100 e Dowling afetaram negativamente o peso de insetos-praga da soja. Plantas de soja pulverizadas no estádio R6 com os tratamentos foram utilizadas para avaliar o efeito do cis-Jasmone sobre ganho de peso do percevejo-marrom, Euschistus heros. Plantas da cultivar Dowling tratadas com cis-Jasmone reduziram significativamente o peso do percevejo. A aplicação do cis-Jasmone também provocou a produção de isoflavonoides nas vagens e nos grãos. Nas vagens foi observado o aumento das formas glicosídicas (daidzina e genistina) e das malonís (daidzina e genistina), assim como das agliconas (daidzeína, gliciteína e genisteína). No grão, observou-se o aumento das concentrações de daidzeína e malonil genistina. Plantas dos mesmos genótipos no estádio V3, foram pulverizadas com os mesmos tratamentos. As folhas de plantas tratadas com Tween 20 e cis-Jasmone reduziram o peso de Anticarsia gemmatalis tanto na cultivar IAC 100 como Dowling. A produção de isoflavonóides nas folhas foi afetada pela aplicação do Tween 20 e cis-Jasmone, aumentando a concentração da malonil (daidzina, glicitina e genistina) e da aglicona daidzeína. Pelas análises foi observado aumento da concentração da fitoalexina coumestrol nas plantas tradadas com Tween 20 e cisJasmone. A influência negativa no peso dos insetos e aumento da concentração dos isoflavonóides sugere que o Tween 20 e o cis-Jasmone tem papel importante na indução da rota dos fenilpropanoides e que estes compostos afetam o desenvolvimento de insetos-praga
Abstract: The spray treatments water; water + Tween 20; and water + Tween 20 + cis-Jasmone in the genotypes BRS 134, IAC 100 and Dowling had negative effects on the weight of insect-pests of soybean. Soybean plants sprayed with treatments at R6 stage were used to evaluate the effect of cis-Jasmone on the weight gain of brown stinkbug, Euschistus heros. Plants of Dowling treated with cis-Jasmone significantly reduced the weight of the stink-bug. The application of cis-Jasmone also triggered the production of isoflavonoids in soybean pods and grains. In the pods, it was observed increasing in the glycosidic (daidzin and genistina), and the malonyl (daidzin and genistin), as well as the aglycone (daidzein, glycitein and genistein) forms. In the grain isoflavonoids daidzein and malonyl genistein concentrations increased. Plants of the same genotypes at V3 stage were sprayed with the same treatments. Leaf plants treated with Tween 20 and cis-Jasmone reduced the weight of Anticarsia gemmatalis in the cultivar IAC 100 and Dowling. The production of isoflavonoids in leaves was affected by Tween 20 and cisJasmone sprayings, increasing the concentration of malonyl (daidzin, genistin and glycitin) and aglycone daidzein. By these analyzes, it was observed increasing in phytoalexin coumestrol concentration in plants treated with Tween 20 and cis-Jasmone. The negative influence on the weight of insects and on the increase of isoflavonoid concentrations suggests that the Tween 20 and cis-Jasmone plays an important role in inducing pathway of phenylpropanoids and that these compounds affect development of insect-pests
Doutor
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Jiang, Feng. "Effects of the Non-ionic Surfactant Tween 80 on the Enzymatic Hydrolysis of Model Cellulose and Lignocellulosic Substrates." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/77223.
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Non-ionic surfactants are known to enhance the biochemical conversion of lignocellulosic (LC) biomass to bioethanol. Their mechanisms of action, however, are incompletely understood. This research was conducted to elucidate the effects of the non-ionic surfactant Tween 80 on the enzymatic hydrolysis of cellulose and LC substrates. Model cellulose substrates were prepared from cellulose nanocrystals (CNCs) obtained by sulfuric acid hydrolysis of wood pulp. Two methods were developed for the removal of the sulfate groups on the CNCs, resulting from the use of sulfuric acid in their preparation. The effect of sulfate groups, which may be introduced into LC biomass during pretreatment with sulfuric acid, on the enzymatic hydrolysis of cellulose was studied with model cellulose substrates prepared from CNCs with different sulfate group densities. Adsorption of cellulases onto sulfated substrates increased with increasing sulfate group density but their rate of hydrolysis decreased. The decrease indicated an inhibitory effect of sulfate groups on the enzymatic hydrolysis of cellulose, possibly due to non-productive binding of the cellulases onto the substrates through electrostatic interactions instead of their cellulose binding domains. The effect of Tween 80 on the adsorption of cellulases onto lignin, often present as residual lignin in pretreated biomass, was studied with model lignin substrates, prepared from kraft lignin, organosolv lignin, and milled wood lignin. Cellulases appeared to adsorb onto the lignin substrates via both hydrophobic and polar interactions. Tween 80 molecules on the lignin substrates seemed to hinder cellulase adsorption via hydrophobic interactions and reduced the adsorption rate. Finally, the effects of lignin and Tween 80 on the enzymatic hydrolysis of cellulose and LC substrates were studied. Lignin hindered both the adsorption of cellulases onto the substrates and the enzymatic hydrolysis of the substrates. Tween 80 was found to form surfactant–protein complexes with cellulases in solution without compromising cellulase activity. Either substrate-adsorbed or in solution, Tween 80 had no effect on the hydrolysis of cellulose by cellulases. Substrate-adsorbed Tween 80 increased the apparent enzymatic hydrolysis rates of LC substrates but the ability of Tween 80 to increase their apparent hydrolysis rate depended strongly on their structural properties and the chemical properties of the lignin. Hence, Tween 80 may be able to mitigate the inhibitory effect of lignin on the enzymatic hydrolysis of pretreated biomass.Ph. D.
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Yang, Xiaomei Sibley Jeffrey Lynn. "Effects of a nonionic surfactant on plant growth and physiology." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SUMMER/Horticulture/Dissertation/Yang_Xiaomei_2.pdf.
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Brock, Mary Katherine. "Exploring apparel relationships and body image of tween girls and their mothers through qualitative analysis of segmented focus groups." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Spring%20Theses/BROCK_MARY_9.pdf.
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Santos, João Thiers Mendonça. "Estudo da interação de fármacos em sistemas micelares formados por tween 80 por espalhamento de raios X a baixo ângulo." Pós-Graduação em Química, 2017. https://ri.ufs.br/handle/riufs/6763.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESMicelles are thermodynamically stable systems, formed after reaching a minimum concentration of surfactant in the solution, and is called the critical micellar concentration (CMC). The tensoactives are amphiphilic substances, that is, they have a polar region (head) and another apolar (tail) well defined in the molecular structure, being the tensoactive tween 80 chosen for this work. The CMC of this surfactant was found by ultraviolet-visible spectroscopy, through the absorption of a probe molecule that was ibuprofen at work. The CMC value is between 1.10-4 and 2.10-4 mM. Micelles have a great potential in the solubilization of poorly soluble drugs in aqueous solution that are being reused for different purposes than the current ones, besides taking drugs that have previously been abandoned due to their lack of solubility, for example in blood plasma, with we can increase the bioavailability of the same in the body, and can function as nanoreservatories of drugs thus minimizing the side effects of these, and help in the correct direction in which these drugs are discharged. Given this relevance, this work aims to understand how and where the interaction of the tween-80 formed micelles with the drugs, varying the pH and the concentrations of these. The drugs used in this study were carisoprodol, ibuprofen and sodium ibuprofen, since they have different characteristics in relation to the molecular polarity distribution. The technique used to perform these analyzes was the low angle X-ray scattering (SAXS), through which it is possible to analyze changes of shapes and sizes of the nanometric order. From the experimental observations, it was possible to say that for more effective interaction between the micelles and the drugs, it is necessary that they have a well defined and expressive apolar region, in terms of volume, in some region of the molecule, since the carisoprodol did not alter the SAXS curves of the micelles when it was present in the solution. Ibuprofen and sodium ibuprofen were able to cause significant changes in the SAXS curves, either in terms of low or high angle displacement or effects of attractive or repulsive interferences on the micelles. The modeling of the SAXS curves revealed the geometries acquired by the micelles, which at pH 4 and pH 7 alternated between a core and a cylindrical shell with an elliptical or circular cross-section depending on the drug or its concentration and at pH 9, The only cross section presented was elliptical geometry. The internal cylinder size of pH 4 micelles without drug was 33.9 Å, increasing to 43.4 Å with 30 mM ibuprofen and 53.7 Å with 30 mM ibuprofen sodium. At pH 7 and 9, there was little change in these lengths. A theoretical study was also carried out to better understand the micelle-drug interaction and, for this, the atomic charges, the polar and polar light, and the optimization of the structures of the substances used in this work were obtained. Tween 80 was optimized by the semi-empirical method PM3 (Parametric Method Number 3), while both carisoprodol and ibuprofen were optimized by the ab initio DFT (Density Functional Theory) method.
As micelas são sistemas termodinamicamente estáveis, formadas após atingirem uma concentração mínima de tensoativo na solução, que é chamada de concentração micelar crítica (CMC). Já os tensoativos são substâncias anfifílicas, ou seja, possuem uma região polar (cabeça) e outra apolar (cauda) bem definidas na estrutura molecular, sendo o tween 80 o tensoativo escolhido para este trabalho. A CMC deste tensoativo foi encontrada por meio da espectroscopia no ultravioleta-visível, por meio da absorbância de uma molécula sonda que, neste trabalho, foi o ibuprofeno. O valor da CMC está entre 1.10-4 e 2.10-4 mM. As micelas apresentam um grande potencial na solubilização de fármacos pouco solúveis em solução aquosa que estão sendo reutilizados para diversos fins, diferentes dos atuais, além de aproveitar drogas que anteriormente foram abandonadas devido a sua falta de solubilidade, por exemplo, no plasma sanguíneo, com isso, conseguem aumentar a biodisponibilidade dos mesmos no organismo, podendo funcionar como nanoreservatórios de fármacos minimizando, desse modo, os efeitos colaterais destes, além de ajudar no direcionamento correto em que essas drogas deverão ser descarregadas. Diante de tal relevância, este trabalho propõe-se a entender como e onde ocorre a interação das micelas formadas por tween 80 com os fármacos, variando o pH e as concentrações destes. Os fármacos utilizados neste trabalho foram o carisoprodol, o ibuprofeno e o ibuprofeno sódico, uma vez que apresentam características distintas em relação à distribuição de polaridade molecular. A técnica utilizada para realizar essas análises foi a de espalhamento de raios X a baixo ângulo (SAXS), por meio da qual é possível analisar mudanças de formas e tamanhos da ordem nanométrica. A partir das observações experimentais, foi possível dizer que para ocorrer interação mais efetiva entre as micelas e os fármacos é necessário que estes tenham uma região apolar bem definida e expressiva, em termos de volume, em alguma região da molécula, tendo em vista que o carisoprodol não alterou as curvas de SAXS das micelas, quando estava presente na solução. Já o ibuprofeno e o ibuprofeno sódico conseguiram causar mudanças significativas nas curvas de SAXS, seja em termos de deslocamento para baixo ou alto ângulo ou efeitos de interferências atrativas ou repulsivas nas micelas. O modelamento das curvas de SAXS revelou as geometrias adquiridas pelas micelas, que em pH 4 e pH 7 alternava-se entre um núcleo e uma casca cilíndrica com seção transversal elíptica ou circular a depender do fármaco ou de sua concentração e em pH 9, a única seção transversal apresentada foi a geometria elíptica. O tamanho do cilindro interno das micelas em pH 4 sem fármaco foi de 33,9 Å, passando para 43,4 Å com 30 mM de ibuprofeno e 53,7 Å com 30 mM de ibuprofeno sódico. Já em pH 7 e 9 houve pouca alteração nesses comprimentos. Foi feito também um estudo teórico para melhor compreender a interação micela-fármaco e, para isso, foram obtidos as cargas atômicas, o raio apolar e polar, além da otimização das estruturas das substâncias utilizadas neste trabalho. O tween 80 foi otimizado pelo método semi-empírico PM3 (Parametric Method Number 3), ao passo que tanto o carisoprodol quanto o ibuprofeno foram otimizados pelo método ab initio DFT (Teoria do Funcional de Densidade).
São Cristóvão, SE
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Davis, Roy C. "The Ghost of Carver Ranch." Miami University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=miami1154312646.
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MESQUITA, Amanda Rafaela Carneiro de. "Influência do Tween 80 e do ácido linoleico sobre o crescimento e metabolismo de novas cepas de Lactobacillus paracasei e Lactobacillus plantarum." Universidade Federal de Pernambuco, 2017. https://repositorio.ufpe.br/handle/123456789/25141.
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CAPES
Ácido linoleico conjugado (CLA) é um termo utilizado para designar 28 isômeros de posição do ácido linoleico, associados a diversas atividades farmacológicas, principalmente atividade anticancerígena e antiobesidade. Diferentes gêneros bacterianos estão envolvidos com a produção de CLA e a grande maioria é utilizada como probiótico. São espécies de Lactobacillus, Lactococcus, Bifidobacterium e Pediococcus que possuem a capacidade de biossintetizar CLA a partir do ácido linoleico livre. Diante dessas observações, este trabalho teve por objetivo o isolamento e identificação de cepas de Lactobacillus; avaliação do efeito do Tween 80 sobre o crescimento, a produção de ácidos orgânicos e etanol, e avaliação antimicrobiana de diferentes linhagens de lactobacilos frente bactérias multirresistentes; bem como a determinação da cinética de crescimento em meio de cultura contendo diferentes concentrações de ácido linoleico, com a finalidade de selecionar cepas de lactobacilos produtoras de CLA. As bactérias foram isoladas a partir de uma bebida chamada kefir e identificadas através do sequenciamento de segmentos do gene 16S rDNA e PCRsespecíficas. Foi determinada também a cinética de crescimento das dez cepas isoladas em meio MRS contendo diferentes concentrações de ácido linoleico e Tween 80. Foi observado que não houve influência do Tween 80 sobre o crescimento e produção de metabólitos de todas as espécies de lactobacilos estudadas. O ácido lático foi o metabólito mais produzido, seguido de ácido acético e etanol. O tempo de adaptação das bactérias ao meio MRS contendo ácido linoleico durou até 12 horas e foi dependente da cepa avaliada. As cepas que tiveram uma fase lag prolongada (12 horas) e que apresentaram maior sensibilidade ao ácido linoleico foram todas da espécie L. paracasei (LBFM 01, LBFM 05, LBFM 06 e LBFM 11). L. plantarum (LBFM 02, LBFM 04, LBFM 07, LBFM 08 e LBFM 09) foram as linhagens mais adaptadas à presença do ácido linoleico. Em relação à produção de CLA, L. plantarum LBFM 07 e L. plantarum 09 foram os maiores produtores, sendo trans-10, cis-12-CLA o principal isômero produzido.
Conjugated linoleic acid (CLA) is a term used to denote 28 positional isomers of linoleic acid, associated with several pharmacological activities, mainly anticancer and antiobesity. Different bacterial genera are involved with the production of CLA and the vast majority is used as a probiotic. They are species of Lactobacillus, Lactococcus, Bifidobacterium and Pediococcus that have the ability to biosynthesize CLA from free linoleic acid. In view of these observations, this aimed at the isolation and identification of Lactobacillus strains; the evaluation of the effect of Tween 80 on growth, production of organic acids and ethanol, and the antimicrobial evaluation of different strains of lactobacilli against multiresistant bacteria as well as the determination of the kinetics of growth in culture medium containing different concentrations of linoleic acid, in order to select CLA-producing Lactobacillus strains. Bacteria were isolated from a beverage called kefir and identified through the sequencing of 16S rDNA gene and specific PCR segments. The growth kinetics of the ten strains isolated in MRS medium containing different concentrations of linoleic acid and Tween 80 was also determined. There was no influence of Tween 80 on the growth and production of metabolites of all species of lactobacilli studied. Lactic acid was the most produced metabolite, followed by acetic acid and ethanol. The time for adaptation of the bacteria to the MRS medium containing linoleic acid lasted up to 12 hours and depended on the strain evaluated. The strains that had a prolonged lag phase (12 hours) and showed the highest sensitivity to linoleic acid were all of L. paracasei (LBFM 01, LBFM 05, LBFM 06 and LBFM 11). L. plantarum (LBFM 02, LBFM 04, LBFM 07, LBFM 08 and LBFM 09) were the strains most adapted to the presence of linoleic acid. In relation to the CLA production, L. plantarum LBFM 07 and L. plantarum 09 were the major producers, and trans-10, cis-12-CLA was the main isomer produced.
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Rodrigues, Ciro Jos? Ferreira. "Estudo da efic?cia do tensoativo sorbitano tween 80 veiculado em nanoemuls?o contendo ?leo de soja, como inibidor de corros?o." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17700.
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Nowadays, the use of chemicals that satisfactorily meet the needs of different sectors of the chemical industry is linked to the consumption of biodegradable materials. In this context, this work contemplated biotechnological aspects with the objective of developing a more environmentally-friendly corrosion inhibitor. In order to achieve this goal, nanoemulsion-type systems (NE) were obtained by varying the amount of Tween 80 (9 to 85 ppm) a sortitan surfactant named polyoxyethylene (20) monooleate. This NE-system was analyzed using phase diagrams in which the percentage of the oil phase (commercial soybean oil, codenamed as OS) was kept constant. By changing the amount of Tween 80, several polar NE-OS derived systems (O/W-type nanoemulsion) were obtained and characterized through light scattering, conductivity and pH, and further subjected to electrochemical studies. The interfacial behavior of these NE-OS derived systems (codenamed NE-OS1, S2, S3, S4 and S5) as corrosion inhibitors on carbon steel AISI 1020 in saline media (NaCl 3.5%) were evaluated by measurement of Open Circuit Potential (OCP), Polarization Curves (Tafel extrapolation method) and Electrochemical Impedance Spectroscopy (EIS). The analyzed NE-OS1 and NE-OS2 systems were found to be mixed inhibitors with quantitative efficacy (98.6% - 99.7%) for concentrations of Tween 80 ranging between 9 and 85 ppm. According to the EIS technique, maximum corrosion efficiency was observed for some tested NE-OS samples. Additionaly to the electrochemical studies, Analysis of Variance (ANOVA) and Principal Component Analysis (PCA) were used, characterization of the nanoemulsion tested systems and adsorption studies, respectively, which confirmed the results observed in the experimental analyses using diluted NE-OS samples in lower concentrations of Tween 80 (0.5 1.75 ppm)
Atualmente, a utiliza??o de produtos qu?micos que atendam satisfatoriamente as necessidades de diferentes setores da ind?stria qu?mica encontra-se vinculada ao consumo de materiais biodegrad?veis. Neste contexto, o presente trabalho foi desenvolvido contemplando aspectos biotecnol?gicos com o objetivo de se desenvolver um inibidor de corros?o menos agressivo ao meio ambiente. Para tanto, uma nanoemuls?o (denominada de NE-OS) foi obtida com Tween 80 (polioxietileno (20) monooleato), ?leo de soja (OS) e ?gua bidestilada. A modifica??o dos percentuais deste tensoativo sorbitano (entre 9 e 85 ppm) foi avaliada em diagramas de fases em que se manteve constante o percentual da fase ?leo, possibilitando a forma??o do sistema NE-OS em diferentes concentra??es. Desta forma, nanoemuls?es (NE-OS1, S2, S3, S4 e S5) polares (do tipo O/A) foram caracterizadas (an?lise de dispers?o de luz, condutividade e pH) e submetidas a estudos eletroqu?micos. O comportamento interfacial destes sistemas nanoemulsionados como inibidores de corros?o na presen?a de a?o-carbono AISI 1020, em meio salino (NaCl 3,5%) foi avaliado pela determina??o do Potencial de Circuito Aberto (OCP), Curvas de Polariza??o (obtidas pela extrapola??o das curvas de Tafel) e Espectroscopia de Imped?ncia Eletroqu?mica (EIE). De acordo com os resultados obtidos pelas an?lises das Curvas de Polariza??o, foi poss?vel caracterizar o sistema NE-OS (e suas varia??es) como inibidores mistos com efici?ncias m?ximas de inibi??es quantitativas (98,6% - 99,7%) para NE-OS1 e NE-OS2 (9 - 85 ppm do tensoativo). No entanto, de acordo com a t?cnica EIE, as efici?ncias m?ximas de inibi??es quantitativas foram observadas para v?rias amostras deste sistema NE-OS. Como ferramentas adicionais aos estudos eletroqu?micos foram realizados quimiom?tricos de An?lise de Vari?ncia (ANOVA) e An?lise de Componentes Principais (PCA), utilizadas, respectivamente, para caracteriza??o das nanoemuls?es e estudo de isotermas de adsor??o, que confirmaram os resultados observados nas investiga??es experimentais em que se utilizaram as nanoemuls?es dilu?das com o tensoativo em concentra??es reduzidas (0,5 1,75 ppm)
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Rowe, Abbey Marie. "From Princess to Provocateur: A Content Analysis of Preteen Fashion in Teen Magazine, 1960-2005." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1333656262.
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Brain, Ruth. "Being a teen, tween and in-between girl in Mitchell's Plain: toward a heterogenous conception of youth agency in a Global South city." Master's thesis, University of Cape Town, 2020. http://hdl.handle.net/11427/32457.
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How do young South Africans assert agency? This study uses Emirbayer and Mische's (1998) theoretical conception of agency as temporally embedded and constantly reconfiguring; and combines it with the idea of shifting strategies as manifestations of agency. I introduce the seminal works in South African everyday youth literature to orient my study to explore how youth in South Africa assert agency through everyday strategies. Using qualitative methods - photo voice, focus groups, mapping and individual interviews - with four teenage girls from a high school in Mitchell's Plain, this study offers an enriched approach to a conception of youth agency, by overlaying a youth study with a theoretical conception of agency. The girls' everyday accounts show that as young teenagers they are waiting to enter the unknown prospect of teenagehood. To navigate their everyday lives, they draw on iterative (past), practical evaluative (present) and projective (future) agency in shifting configurations to maximise their agency in their lifeworlds. Although their agency is in tension with structures of safety concerns, familial expectations and culturally validated narratives of being a 'good girl'; the girls find ways around and through these limitations by strategically asserting their agency. This study applies a comprehensive theory of agency to a small youth study with rich everyday descriptions, in an effort towards enriching and grounding a conception of youth agency in an urban environment in the Global South.
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Kawasaki, Yukie. "Aminoglycosides and Syringomycin E as Fungicides Against Fusarium graminearum in Head Blight Disease." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/202.
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Fusarium graminearum is one of the most problematic phytopathogens in US agriculture. This fungus causes head blight, foot rot, and damping off on wheat and barley. The infection lowers the grain yield and causes contamination of the grain product with mycotoxins. Effective control measures are lacking, and new fungicides that kill F. graminearum but remain safe and economical to use are needed. Newly synthesized aminoglycosides (JL22, JL38, JL39, JL40, NEOF004, NEOF005), classic aminoglycosides (amikacin, gentamicin, kanamycin A, kanamycin B, neomycin, and ribostamycin), and a lipopeptide, syringomycin E (SRE), were studied to determine their antifungal potential to control F. graminearum. Aminoglycosides are protein synthesis inhibitors that mainly target bacteria, but a few were recently observed to kill fungi. They consist of an aminocyclitol ring bound with two or more amino sugars. Novel aminoglycosides were recently synthesized using novel glycodiversification synthetic schemes involving the replacement of the original amino sugars with unusual amino sugars. SRE is an antifungal lipodepsinonapeptide produced by Pseudomonas syringae pv. syringae. This bacterium is an opportunistic pathogen in a wide range of plant species and produces several fungicidal lipopeptides. SRE forms pores on fungal plasma membrane and causes ion fluxes. An enhancement of its antifungal activity is reported in the presence of rhamnolipid surfactants. The antifungal activities of various aminoglycosides, SRE, and a SRE-rhamnolipids mixture were determined against F. graminearum by measuring in vitro minimum inhibition concentrations (MICs) and in planta lesion area and chlorosis development using a leaf infection assay protocol. It was determined that using Tween® 20 at 0.2 % (v/v) concentration in the leaf infection assay promotes lesion development by F. graminearum with minimum phytotoxicity. In vitro, SRE, SYRA, and synthetic aminoglycoside JL38 showed the best antifungal activities. With the in planta assay, all three antifungal agents prevented infection by F. graminearum. However, inconsistent phytotoxicities were observed with SRE and SYRA that were influenced by the Tween® 20 surfactant included in the leaf infection assay. How Tween® 20 induces these phytotoxic inconsistencies is not known.
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Nguyen, Phuong Khanh Quoc. "Cyclic Voltammetric and Square Wave Anodic Stripping Voltammetric Analysis of Lead and Cadmium Utilizing the Novel Titanium Dioxide/ Zirconium Dioxide/ Tween 80 Carbon Paste Composite Electrode." Wright State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=wright1386851133.
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Mortensen, Trent W. "The Hypericum Perforatum Herb as an Antimycobacterial Agent and Its Implications as an Additional Tuberculosis Medication." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/714.
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An immediate demand exists for new tuberculosis (TB) antibiotics due to the ever-increasing spread of drug-resistant strains. The drug-development process goes through four phases, the first (Phase 0) of which is to demonstrate and investigate drug effectiveness and toxicity. This research investigated the effectiveness of the Hypericum perforatum herb (commonly St. John's wort (SJW)) in its growth inhibition of mycobacteria and its viability effect on human lung cells. Organic-solvent SJW extracts were effective at inhibiting every nonpathogenic genetically sequenced Mycobacterium isolate currently available (six isolates) in preliminary studies. Quantitative studies of five Mycobacterium isolates showed an order of concentration sensitivity to the SJW methanol (MeOH) extract as (high to low) M. JLS, M. KMS, M. phlei (not sequenced), M. MCS, B. subtilis, M. smegmatis, and E. coli, with minimal bactericidal concentrations (MBCs) ranging from 0.33-2.66 mg extract/ml. The SJW compounds hyperforin (Hfn), hypericin (Hpn), and pseudohypericin (Phn) were quantified using a novel HPLC method that utilized common HPLC equipment. A crude MeOH extract solution of 133 mg extract/ml contained 2.26 mg Hfn/ml, 0.77 mg Hpn/ml, and 2.67 mg Phn/ml. Purified Hfn had a MBC of between 6-13 μg/ml for M. JLS in the absence of Tween 80. Tween 80 repressed Hfn (46 μg/ml) inhibition of M. JLS at ≥ 0.025% (v/v). Purified Hpn and Phn showed no inhibition of M. JLS at all assayed concentrations, which were ≤ 27 μg/ml and ≤ 25 μg/ml, respectively. Inhibitory results from the five quantitatively assayed Mycobacterium samples could be extrapolated to M. tuberculosis, as these isolates have as high as 72% genetic homology to the pathogen. The crude MeOH extract and Hfn were lethal to the human carcinomic alveolar epithelial lung cell line A549 at 1.3 mg extract/ml (crude extract) and ≥ 11 μg/ml (Hfn), with a Hfn LD50 of 3-6 μg/ml (5.6-11.2 μmol/L). Because Hfn is antiproliferative to a list of other carcinomic cell lines in the same concentration range, the A549 cell line may be added to that list. The addition of M. JLS cells (5x106 cells/cm2) to penicillin-streptomycin-containing A549 culture (which killed the bacteria) did not affect A549 viability.
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Tabone, Sara. "Il fare mediale. Ricerca su usi e concezioni di ragazzi di 10 e 11 anni in merito ai nuovi media (cellulare, computer, internet) in ambito domestico e percezioni dei comportamenti di mediazione genitoriale." Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3426977.
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The presence and the rapid diffusion in Italian children’s life of new media, such as mobile phone, personal computer and the Internet, is broadly recognized both by statistical surveys (Censis, 2007; Istat, 2008; 2009) and by the research. Among national and international studies, three inquiry path particularly interesting from an educational point of view emerge: one deals with the mapping of media uses, stated by frequency, length and function approached (Pira & Marrali, 2007; Mussinelli, 2009); one deals with conceptions about usage, or the meaning children give to their media practices (Downes & Reddacliff, 1997; Leung & Wei, 2000; Livingstone & Bovill, 2001b; Rivoltella, 2006); and the third one deals with the adults’ presence and the guidance or mediation activities of children’s media uses (Bybee et al., 1982; Nathanson, 2001; Nikken & Jansz, 2004; Livingstone, 2007). Many of these aspects are considered into the domestic context, as the family is the first place where meanings, norms and values on media use are supposed to be socialized and negotiated (Pasquier, 2001), according also to the “domestication” theory (Silverstone et al., 1992).
The exploratory study here presented investigates the relationships between children and the media – mobile phone, computer and the Internet - inside the domestic context. The research pursues three aims. The first one is finding similarities and differences between the dimensions of meanings that accompany children usage of mobile phone, computer and the Internet. The second one is finding similarities and differences between the dimensions of parental mediation on children’s usage of the three media considered. The third one is finding possible correlations between children’s usage conceptions and their perception of parental mediation activities, to understand if children perceive an educational intervention by parents or if they perceive that parents do not interfere in their interactions with the media, in line with the research on the “bedroom culture” (Bovill & Livingstone, 2001), or with a more general lack of educational presence.
Through a closed format questionnaire, self-completed by 272 tweens (Tufte et al., 2005) aged 10 and 11 years, the research surveys practical uses of mobile phone, computer and the Internet, conceptions about media personal experiences and practices, and perceptions about interventions of mediation by parents. All of these aspects are inquired in relation to all the media considered.
The data obtained by analyses (percentage frequencies, factor analysis, analysis of variance and analysis of correlation) show: different levels of ownership and media usage, the prevailing media functions experienced, the presence of “others” during the appropriation of the media and in the current use, some dimensions underlying children’s media practices, some dimensions perceived by children of parental mediation, different variables that affect these dimensions, and some relationships among the factors emerged by usage conceptions and by perceptions of parental mediation activity analyses.La presenza e la rapida diffusione nella vita dei ragazzi italiani dei nuovi media, come il cellulare, il personal computer e Internet, sono ampiamente attestate sia da indagini statistiche (Censis, 2007; Istat, 2008; 2009) sia dalla ricerca scientifica. In merito a quest'ultima, negli studi in ambito nazionale e internazionale si possono individuare tre aree di studio particolarmente interessanti da un punto di vista educativo: una riguarda la mappatura degli usi mediali da parte dei minori, tramite la rilevazione di frequenza, durata e funzioni esperite (Pira & Marrali, 2007; Mussinelli, 2009); un’altra si rivolge alle concezioni legate all’uso, o al senso che i ragazzi attribuiscono alle loro pratiche mediali (Downes & Reddacliff, 1997; Leung & Wei, 2000; Livingstone & Bovill, 2001; Rivoltella, 2006); mentre la terza si occupa di rilevare la presenza degli adulti e delle loro attività di guida - o mediazione - in merito all’uso dei media da parte dei ragazzi (Bybee et al., 1982; Nathanson, 2001; Nikken & Jansz, 2004; Livingstone, 2007). Molti di questi aspetti vengono trattati all’interno del contesto domestico, dal momento che, anche in accordo con la teoria della domestication (Silverstone et al., 1992), la famiglia è il primo luogo in cui significati, norme e valori sull’uso dei media sono socializzati e negoziati (Pasquier, 2001). La ricerca presentata in questo lavoro indaga le relazioni dei ragazzi con i media più diffusi: cellulare, computer e Internet, all’interno del contesto domestico, e persegue tre obiettivi. Il primo consiste nel rilevare analogie e differenze tra le dimensioni di senso che accompagnano il fare mediale dei ragazzi rispetto ai tre media suddetti. Il secondo tende a rilevare analogie e differenze nelle percezioni di mediazione genitoriale riguardo all’utilizzo di tali media da parte dei ragazzi. Il terzo è volto a individuare possibili relazioni tra le concezioni dei ragazzi e le loro percezioni delle attività di mediazione genitoriale, al fine di comprendere se i ragazzi avvertano un intervento educativo dei genitori nel loro rapporto con i media, in linea con la teoria della bedroom culture (Bovill & Livingstone, 2001). Attraverso un questionario auto compilato da 272 tweens (Tufte et al., 2005), ragazzi di 10 e 11 anni, la ricerca indaga: usi di cellulare, computer e Internet, concezioni in merito alle personali esperienze e pratiche con i tre media e percezioni dei ragazzi degli interventi di mediazione genitoriali. L’analisi dei dati - frequenze percentuali, analisi fattoriale, analisi di varianza e analisi di correlazione – evidenzia: diversi livelli di possesso e utilizzo dei tre media da parte dei ragazzi, le principali funzioni esperite, la presenza di “altri” in fase di appropriazione dei media e nell’uso attuale, le dimensioni attorno a cui si aggregano le loro concezioni sull’uso dei media e le loro percezioni della mediazione genitoriale, l’incidenza di alcune variabili indipendenti su queste dimensioni e le principali relazioni tra concezioni d’uso e percezioni di mediazione.
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Vu, Dang Hoang. "The influence of excipient composition and functionality on the microstructure of fatty alchohol - Tween 60 - water ternary systems and the impact of these factors on drug release." Thesis, University of Strathclyde, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424360.
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Mabentsela, Nombongo. "Optimization of the enzymatic conversion of maize stover to bioethanol / by Nombongo Mabentsela." Thesis, North-West University, 2010. http://hdl.handle.net/10394/4852.
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The severe effects associated with global warming and the rapid increase in oil prices are the
driving forces behind the demand for clean carbon–neutral and biofuels such as bioethanol.
Research studies are now focusing on using lignocellulosic biomass for bioethanol production due
to concerns about food security and inflation. The chosen feedstock for this study was maize stover,
given that it is the most abundant agricultural residue in South Africa. Maize stover consists of
structural carbohydrates that can be enzymatically converted into fermentable sugars. The major
drawback in the production of bioethanol from lignocellulosic biomass has been its high equipment
and operational costs due to the use of acids and high enzyme loadings. The aim of this study was
to investigate the possibility of optimizing the enzyme hydrolysis of pre–treated maize stover
without further increasing the amount of enzymes. The maximum glucose yield attained was
690 ± 35 mg of glucose per gram of substrate which is equivalent to a conversion efficiency of
119%. The preferred pre–treatment method used was 3% sulphuric acid for 60 minutes at 121oC and
the enzymatic hydrolysis process was performed at a 5% substrate loading, 50oC and pH 5.0 using
30 FPU per gram of cellulose in the presence of 1.25 g.L–1 of Tween 80 for 48 hours. The addition
of Tween 80 increased the glucose yields by 23 % and thus, it has the potential of lowering the
overall process costs by increasing the glucose yield without further addition of enzymes.
Keywords: Bioethanol, maize stover, lignocellulosic biomass, pre–treatment, enzymatic hydrolysisThesis (M.Sc. Engineering Sciences (Chemical Engineering))--North-West University, Potchefstroom Campus, 2011.
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Filon, Michele R. "To Tweet or not to Tweet." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1457364934.
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Puligheddu, Giacomo. "Tweet Tracker: analisi e visualizzazione di tweet geolocalizzati." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
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Il progetto consiste nella realizzazione di un programma che sfrutti le API del social network Twitter. Tale progetto ha come obiettivo quello di mostrare le potenzialità degli strumenti messi a disposizione da Twitter per la raccolta di dati dalla sua piattaforma. I tweet possono essere un mezzo tramite la quale è possibile ottenere informazioni da eventi di vario tipo; se geolocalizzati acquisiscono ulteriore importanza perché forniscono un riscontro degli avvenimenti da una posizione precisa.
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Davanço, Taciana. "Desenvolvimento e caracterização de biofilmes a base de gelatina, triacetina, acido estearico ou acido caproico e surfactantes." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/255982.
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Orientador: Carlos Raimundo Ferreira GrossoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Desenvolvimento de biofilmes tem crescido devido a possibilidade de substituição parcial de materiais plásticos não degradáveis. Proteínas e polissacarídeos têm sido utilizados para a produção de filmes com boas propriedades mecânicas. Porém filmes a partir desses materiais apresentam alta permeabilidade ao vapor de água. Uma alternativa usada para diminuir a permeabilidade ao vapor de água dos filmes é a incorporação de substancias hidrofóbicas na composição da solução filmogênica, porém a incorporação dessas substâncias na matriz filmogênica não ocorre de maneira homogênea. Com o objetivo de melhorar a incorporação das substâncias hidrofóbicas na matriz protéica do filme foram adicionados os surfactantes (SDS e Tween 80), que são compostos orgânicos constituídos por moléculas anfifílicas, contendo uma parte polar e outra apolar, com o intuito desta substância interagir na proteína e no ácido graxo, tornando a matriz filmogênica menos heterogênea. O efeito do pH também foi estudado, com a finalidade de observar se este exerce influência na homogeneidade da matriz filmogênica. Os ácidos graxos utilizados no trabalho foram o ácido capróico (6C), e o ácido esteárico (18C), com o objetivo de avaliar e comparar se o número de carbonos da cadeia do ácido graxo exerce influencia na incorporação da matriz protéica. Os filmes foram caracterizados quanto as propriedades de barreira ao vapor de água e propriedades mecânicas, solubilidade em água, opacidade, isotermas de sorção e calorimetria diferencial de varredura, podendo ser observado que a adição dos surfactantes melhorou a barreira ao vapor de água e diminuiu a resistência à tração dos filmes, não sendo observado diferenças na cor e opacidade dos filmes . Posteriormente foram analisadas as características morfológicas, através da microscopia ótica, microscopia eletrônica de varredura e microscopia confocal de varredura a laser, observando que o ajuste do pH e a adição do surfactante modificam a estrutura morfológica do filme
Abstract: Development of biofilms has grown considering the possibility of partial substitution of plastic materials not degradable. Proteins and polysaccharides have been used for the production of films with good mechanical properties. However films produced with these materials present high water vapor permeability to the water vapor. An used alternative to improve the water vapor barrier of the films is the incorporation of hydrophobic substances in the composition of the filmogenic solution, however the incorporation of these substances in the filmogenic matrix does not occur in homogeneous way. Thus with, the objective to improve the incorporation of hydrofhobic substances in the protein matrix of the film surfactants had been added (SDS and Tween 80). They are organic compounds constituted by anphiphilics molecules, incluing a polar part and other apolar, with the intention that is substances improve the interaction between the protein and the fats acids, producing a less heterogeneous filmogenic matrix. The effect of pH also was studied, with the purpose to observe if this produce influence in the homogeneity of the filmogenic matrix. The fats acids used in this work were the caproic acid (6C), and the stearic acid (18C), with the objective to evaluate and to compare if the carbon number of the fats acids exerts influences in the incorporation on the protein matrix. The films were characterized with respect to the properties of barrier to the water vapor, solubility in water, opacity, isotherms of sorption and thermal properties, being able to be observed that the addition of the surfactants improved the water vapor permeability and decreased the tensile strenght of the films, not being observed differences in the color and opacity of the films. Later the morphologic characteristics had been analyzed, through optics microscopy, scanning electron microscopy and confocal laser scanning microscopy, observing that the adjustment of pH and the addition of the surfactant modify the morphological structure of the films
Mestrado
Nutrição Experimental e Aplicada à Tecnologia de Alimentos
Mestre em Alimentos e Nutrição
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Andrade, Milton. "Heavy metal removal from bilge water by electrocoagulation treatment." ScholarWorks@UNO, 2009. http://scholarworks.uno.edu/td/1092.
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The purpose of this research was to observe the removal efficiency for copper (Cu), nickel (Ni), and zinc (Zn) using Electrocoagulation (EC) technique in a continuous flow reactor with a synthetic bilge water emulsion; and additionally, to discuss the operation cost of the treatment. The optimal configuration for EC treatment used combined electrodes, aluminum and carbon steel; flow rate of 1 L/min; effluent recycling and 7.5 amps; this optimal configuration achieved 99% of zinc removal efficiency, 70% of both, copper and nickel removal efficiency, and low operation costs. The current intensity did not have significance incidence on the removal efficiency. The analysis of cost per gram of removed contaminant indicated that nickel had an average cost of $1.95 per gram removed, zinc and copper had $0.60 and $0.88 per gram removed, respectively. To develop additional experiments with the EC reactor are required in order to optimize metal removal efficiency.
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Andersson, Camilla, and Hannah Nystrand. "Tweet, tweet, promotionmixens nya kläder : En undersökning till vad Twitter används till, sett utifrån promotionmixen." Thesis, Linnéuniversitetet, Ekonomihögskolan, ELNU, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-11185.
Full textAbstract:
Twitter används av ett brett spektrum av företag, alltifrån stora bolag såsom Google, till mindre företag såsom lokala caféer. I den här undersökningen ser vi på användningen av Twitter i tre små– och medelstora företag. Promotionmixen användes som plattform, vilken består av reklam, sales promotion, personlig försäljning, public relations och direkt marknadsföring, för att kunna fastställa till vad Twitter används. Syftet är att beskriva och skapa en förståelse för hur Twitter används, med hjälp av promotionmixen. Intervjuer, såväl som innehållsanalys, utfördes. Public relations var det Twitter först och främst användes till, över hälften av alla tweets var av karaktären public relations. De andra delarna av promotionmixen användes också på Twitter, dock var personlig försäljning det minsta användningsområdet. Andra områden hittades även, men promotionmixen var det Twitter användes mest till.
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David, Renée S. "To Tweet or Not to Tweet: An Investigative Analysis of the Government of Canada's Social Media Practices." Thesis, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/30355.
Full textAbstract:
The concept of social media is top of mind for Canadians today. Decision makers, such as the Canadian government, try to identify ways in which they can benefit from tools such as Twitter. This thesis is an investigative analysis that studies how the Canadian government currently uses social media networks. Based on the conceptual framework of Rogers’ diffusion of innovations (2003) and Qualman’s socialnomics theory (2013), the study aims to define how members of the Parliamentary Press Gallery use the Government of Canada tweets. Through a series of interviews with members of the press and government communications executives, a themed analysis was conducted to demonstrate how Twitter is being used and if a dialogue exists between federal institutions and reporters. The research unveiled that the Government of Canada uses social media as a one-to-many broadcasting channel, not actively engaging in online dialogue with members of the press. Conversely, journalists use Twitter as a wire service to obtain instant information, and to gain insight from the consumers. However, they are not interested in conversing with the public service on social media as they want to protect the exclusivity of their story, and they criticize the anonymity of the government corporate accounts as having an impact on its credibility.
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Krithivasan, Bhavani. "Cross-Language tweet classification using Bing Translator." Kansas State University, 2017. http://hdl.handle.net/2097/38556.
Full textAbstract:
Master of ScienceDepartment of Computing and Information Sciences
Doina Caragea
Social media affects our daily lives. It is one of the first sources for finding breaking news. In particular, Twitter is one of the popular social media platforms, with around 330 million monthly users. From local events such as Fake Patty's Day to across the world happenings - Twitter gets there first. During a disaster, tweets can be used to post warnings, status of available medical and food supply, emergency personnel, and updates. Users were practically tweeting about the Hurricane Sandy, despite lack of network during the storm. Analysis of these tweets can help monitor the disaster, plan and manage the crisis, and aid in research. In this research, we use the publicly available tweets posted during several disasters and identify the relevant tweets. As the languages in the datasets are different, Bing translation API has been used to detect and translate the tweets. The translations are then, used as training datasets for supervised machine learning algorithms. Supervised learning is the process of learning from a labeled training dataset. This learned classifier can then be used to predict the correct output for any valid input. When trained to more observations, the algorithm improves its predictive performance.
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Costa, Sayonara Melo. "Tweet: reelaboraÃÃo de gÃneros em 140 caracteres." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9323.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoO presente trabalho discute o processo de reelaboraÃÃo de gÃneros na formaÃÃo das postagens do Twitter. Para tanto, investigamos como o esquema de funcionamento e a dinÃmica de valores dessa rede social inspiram a manipulaÃÃo de diferentes padrÃes genÃricos que, ao serem migrados para o seu interior, sÃo submetidos ao labor de seus usuÃrios. Conduzimos nossa discussÃo à luz da anÃlise de redes sociais praticada por Recuero (2009; 2010), das reflexÃes epistemolÃgicas acerca da natureza dos gÃneros do discurso formuladas por Bakhtin ([1979] 2011), do conceito de propÃsito comunicativo cunhado e esmerado por Swales (1990; 2004), Askhave e Swales (2001) e Bhatia (1993; 2001) e da concepÃÃo de reelaboraÃÃo, conforme vem sendo atualizada desde AraÃjo (2006) atà Zavam (2009) e Costa (2010). Apoiados nessa base teÃrica e metodolÃgica, empreendemos a anÃlise de 195 postagens e 45 questionÃrios respondidos por usuÃrios do Twitter. Em um primeiro momento, a partir dos Ãndices de propagaÃÃo das postagens, observamos como a dinÃmica de funcionamento da rede social influencia a difusÃo e sedimentaÃÃo de arranjos genÃricos formados a partir de padrÃes e gÃneros distintos. Em um segundo momento, voltamo-nos para a forma dos tweets, identificando que estratÃgias foram utilizadas pelos usuÃrios para intervirem nos gÃneros ao elaborarem seus tweets. Por fim, investigamos, nos exemplos do corpus e junto aos usuÃrios questionados, que propÃsitos comunicativos foram atendidos pelas postagens resultantes desse labor. Os resultados mostraram que, no interior do Twitter, hà uma dinÃmica de funcionamento peculiar, que se reflete nas aÃÃes de linguagem dos atores dessa rede social que, motivados pelo desejo de colocarem-se em evidÃncia e ampliarem suas conexÃes, mobilizam e manipulam padrÃes genÃricos distintos por meio de estratÃgias especÃficas. Os arranjos genÃricos gerados a partir desse esquema possuem propÃsitos comunicativos caracterÃsticos, colocados a serviÃo da prÃpria rede social. Acreditamos que a rotina enunciativa caracterÃstica do Twitter, a mobilizaÃÃo de padrÃes genÃricos distintos e a alteraÃÃo de propÃsitos comunicativos sÃo fatores que, somados, dÃo forma a um constante processo de reelaboraÃÃo de gÃneros, cujos produtos sÃo consumidos e propagados dentro da rede social, retroalimentando-a.
This thesis discusses the process of genre re-elaboration in the formation of Twitter posts. We therefore investigated how the functioning scheme and the value dynamics of this social network inspire the manipulation of different genre patterns that, when migrating to the interior, are submitted to its usersâ work. We conduct our discussion in the light of social network analysis practiced by Recuero (2009; 2010), the epistemological reflections on the discourse genre nature formulated by Bakhtin ([1979] 2011), the communicative purpose concept coined and made neat by Swales (1990; 2004), Askhave and Swales (2001) and Bhatia (1993; 2001) and the re-elaboration concept, as been updated since AraÃjo (2006) until Zavam (2009) and Costa (2010). Supported by this theoretical and methodological basis, we undertook an analysis of 195 posts and 45 questionnaires answered by Twitter users. At first, from the post propagation indexes, we observed how the social network functioning dynamics influences the diffusion and the genre arrays sedimentation formed by patterns and distinct genres. In a second step, we turned to the tweet form, detecting that strategies were used by the users in order to intervene in the genres when elaborating their tweets. Finally, we investigated, in the corpus examples and with the users questioned, that communicative purposes were served by the posts resulting from this work. The results showed that, within Twitter, there is a peculiar functioning dynamics, which is reflected in the language actions of the actors of this social network whom, motivated by the desire to put themselves in evidence and broaden their connections, mobilize and manipulate distinct genre patterns by using specific strategies. The genre arrangements generated from this scheme have distinctive communicative purposes, at the service of the social network itself. We believe that the sum of these factors: peculiar enunciative demand, distinct genre pattern mobilization and communicative purpose modification, is set as a genre re-elaboration constant process, whose products are consumed and propagated within the social network, feeding it back.
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Costa, Sayonara Melo. "Tweet: reelaboração de gêneros em 140 caracteres." www.teses.ufc.br, 2012. http://www.repositorio.ufc.br/handle/riufc/8258.
Full textAbstract:
COSTA, Sayonara Melo. Tweet: reelaboração de gêneros em 140 caracteres. 2012. 119f. – Dissertação (Mestrado) – Universidade Federal do Ceará, Departamento de Letras Vernáculas, Programa de Pós-graduação em Linguística, Fortaleza (CE), 2012.Submitted by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2014-06-10T14:17:08Z No. of bitstreams: 1 2012_dis_smcosta.pdf: 2932081 bytes, checksum: 82dd8dc3e101c6097ee8f9ba63d737f4 (MD5)
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This thesis discusses the process of genre re-elaboration in the formation of Twitter posts. We therefore investigated how the functioning scheme and the value dynamics of this social network inspire the manipulation of different genre patterns that, when migrating to the interior, are submitted to its users’ work. We conduct our discussion in the light of social network analysis practiced by Recuero (2009; 2010), the epistemological reflections on the discourse genre nature formulated by Bakhtin ([1979] 2011), the communicative purpose concept coined and made neat by Swales (1990; 2004), Askhave and Swales (2001) and Bhatia (1993; 2001) and the re-elaboration concept, as been updated since Araújo (2006) until Zavam (2009) and Costa (2010). Supported by this theoretical and methodological basis, we undertook an analysis of 195 posts and 45 questionnaires answered by Twitter users. At first, from the post propagation indexes, we observed how the social network functioning dynamics influences the diffusion and the genre arrays sedimentation formed by patterns and distinct genres. In a second step, we turned to the tweet form, detecting that strategies were used by the users in order to intervene in the genres when elaborating their tweets. Finally, we investigated, in the corpus examples and with the users questioned, that communicative purposes were served by the posts resulting from this work. The results showed that, within Twitter, there is a peculiar functioning dynamics, which is reflected in the language actions of the actors of this social network whom, motivated by the desire to put themselves in evidence and broaden their connections, mobilize and manipulate distinct genre patterns by using specific strategies. The genre arrangements generated from this scheme have distinctive communicative purposes, at the service of the social network itself. We believe that the sum of these factors: peculiar enunciative demand, distinct genre pattern mobilization and communicative purpose modification, is set as a genre re-elaboration constant process, whose products are consumed and propagated within the social network, feeding it back.
O presente trabalho discute o processo de reelaboração de gêneros na formação das postagens do Twitter. Para tanto, investigamos como o esquema de funcionamento e a dinâmica de valores dessa rede social inspiram a manipulação de diferentes padrões genéricos que, ao serem migrados para o seu interior, são submetidos ao labor de seus usuários. Conduzimos nossa discussão à luz da análise de redes sociais praticada por Recuero (2009; 2010), das reflexões epistemológicas acerca da natureza dos gêneros do discurso formuladas por Bakhtin ([1979] 2011), do conceito de propósito comunicativo cunhado e esmerado por Swales (1990; 2004), Askhave e Swales (2001) e Bhatia (1993; 2001) e da concepção de reelaboração, conforme vem sendo atualizada desde Araújo (2006) até Zavam (2009) e Costa (2010). Apoiados nessa base teórica e metodológica, empreendemos a análise de 195 postagens e 45 questionários respondidos por usuários do Twitter. Em um primeiro momento, a partir dos índices de propagação das postagens, observamos como a dinâmica de funcionamento da rede social influencia a difusão e sedimentação de arranjos genéricos formados a partir de padrões e gêneros distintos. Em um segundo momento, voltamo-nos para a forma dos tweets, identificando que estratégias foram utilizadas pelos usuários para intervirem nos gêneros ao elaborarem seus tweets. Por fim, investigamos, nos exemplos do corpus e junto aos usuários questionados, que propósitos comunicativos foram atendidos pelas postagens resultantes desse labor. Os resultados mostraram que, no interior do Twitter, há uma dinâmica de funcionamento peculiar, que se reflete nas ações de linguagem dos atores dessa rede social que, motivados pelo desejo de colocarem-se em evidência e ampliarem suas conexões, mobilizam e manipulam padrões genéricos distintos por meio de estratégias específicas. Os arranjos genéricos gerados a partir desse esquema possuem propósitos comunicativos característicos, colocados a serviço da própria rede social. Acreditamos que a rotina enunciativa característica do Twitter, a mobilização de padrões genéricos distintos e a alteração de propósitos comunicativos são fatores que, somados, dão forma a um constante processo de reelaboração de gêneros, cujos produtos são consumidos e propagados dentro da rede social, retroalimentando-a.
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Santos, Lílian 1983. "O pio do passáro = uma análise das funções prototípicas do tweet = The bird's tweet : an analysis of tweet's prototypical functions." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/270420.
Full textAbstract:
Orientador: Anna Christina Bentes da SilvaDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Estudos da Linguagem
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Resumo: Tendo em vista que, de acordo com Sandig (2009), os textos, em certas situações (situacionalidade), cumprem determinadas funções que se referem a certos temas, nosso objetivo, neste trabalho, foi buscar as funções desempenhadas prototipicamente pelos tweets - mensagens de, no máximo, 140 caracteres, postadas em um ambiente na Internet chamado Twitter - produzidos pelos sujeitos escolhidos para nossa pesquisa. A partir das funções encontradas, evidenciamos também a situação em que elas são desempenhadas e o tema que desenvolvem. De acordo com Bakhtin (2003), o enunciado é marcado pela especificidade de sua esfera de atividade, razão pela qual decidimos selecionar, para este trabalho, sujeitos de esferas de atividades diferentes para analisarmos as funções prototípicas de seus tweets. Considerando que as esferas de atividade mais presentes no Twitter são as esferas cotidiana, literária, jornalística e artística, decidimos analisar, da esfera cotidiana, os tweets de Flávia Orci. Da esfera literária, os tweets de Fabrício Carpinejar. Da esfera jornalística, analisaremos os tweets da jornalista Rosana Hermann. Da esfera artística, os tweets de Rafinha Bastos. Analisamos ainda os tweets de João Pismel, que pode ser considerado um híbrido, uma vez que trata de tema da esfera cotidiana, mas age como um sujeito da esfera artística. Analisando os tweets postados por cada sujeito, no período de 15 a 30 de setembro de 2010, encontramos algumas funções prototípicas, isto é, funções que eram desempenhadas - com maior ou menor frequência, dependendo da esfera de atividade - pelos tweets de todos os sujeitos selecionados. Foram elas: informar, interagir e fazer refletir. Essas foram, portanto, as funções discutidas nesta pesquisa. Muito importante para este trabalho é o conceito de texto. Seguindo as abordagens de Koch (2011) e Hanks (1996), consideramos, aqui, texto como uma atividade interacional que preenche uma função comunicativa reconhecível num dado contexto social
Abstract: Considering that, according Sandig (2009), the texts, in certain situations, fulfill certain functions that refer to certain issues, our goal in this work was to seek the functions performed prototypically by the tweets - messages up to 140 characters posted on Twitter - produced by the subjects chosen for our study. From the functions found, we presented also the situation in which the tweets are performed and their theme. According to Bakhtin (2003), the statement is marked by the specificity of its sphere of activity, which is why we decided to select, for this work, subjects of different spheres of activities to analyze the prototypical functions of their tweets. Considering that the spheres of activity more present on Twitter are familiar, literary, journalistic and artistic, we decided to analyze, from familiar, Flavia Orci?s tweets. From the literary sphere, the Fabricio Carpinejar?s tweets. From the journalistic sphere, we will analyze the tweets of the journalist Rosana Hermann. From the artistic sphere, Rafinha Bastos? tweets. We also analyzed the tweets of João Pismel, which can be considered a hybrid, because it deals with the theme of familiar sphere, but acts as a subject of artistic sphere. Analyzing the tweets posted by each subject in the period from 15 to 30 September 2010, we found some prototypical functions, functions that were performed - with more or less often, depending on the sphere of activity - on the tweets of all subjects selected. They were: to inform, to interact and to reflect. These were therefore functions discussed in this study. Very important for this work is the concept of text. Following the approaches of Koch (2011) and Hanks (1996), we consider here the text as an interactive activity that fills a recognizable communicative function in a given social context
Mestrado
Linguistica
Mestra em Linguística
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Oliveira, Dayane Xavier de. "Estudo da formação de micelas e microemulsões contendo nifedipina : influência das fases na estrutura dos sistemas." Pós-Graduação em Química, 2014. https://ri.ufs.br/handle/riufs/6087.
Full textAbstract:
Micelles (MIs) and microemulsions (MEs) are classified as stabilized systems by surfactants and are very similar with respect to their structure and physico-chemical properties. As for the applicability, they have been deployed by being able to carry drugs which have a limited systemic bioavailability by oral route. The formation of these systems is mainly dependent on the types of components used, making it important to study its influence on the structure. The goal of this study was to obtain and characterize micellar and microemulsion systems (containing essential oil of Citrus sinensis (L.) Osbeck as oil phase) stabilized by a nonionic surfactant (Tween 80) and short-chain cosurfactant (alcohol ethyl) which may be used as a delivery system for nifedipine (NFD a model drug) seeking to verify the influence of the phases and the interaction of the drug in the structure of these systems. Ternary and pseudoternary phase diagrams for MIs and MEs, respectively, and were obtained from the formation regions, formulations were selected for physico-chemical characterization and incorporation of NFD. The macro and microscopic aspects were evaluated using polarized light microscopy (MLP), measures pH, electrical conductivity and surface tension. The average droplet size was measured by dynamic light scattering (DLS) and small angle x-ray scattering (SAXS). The results demonstrated that such systems are stable, optically isotropic and transparent in the absence and presence of drug. The droplet size decreases with increasing amount of surfactant to MIs and the mixture surfactant/cosurfactant to the MEs. The influence of the cosurfactant in MIs was negligible. The increase of the amount of oily phase in MEs caused an increase in the droplet size. The presence of NFD no influence on the structure of MIs, but for the MEs increased droplet size, suggesting that the NFD is the internal phase of the MEs. The modeling by SAXS curves for MIs and MEs most diluted were made and showed the interaction between the NFD and systems, confirming the previous results. Studies by Fourier Transformed Infra Red (FTIR) confirmed the interaction between MIs and MEs with the stratum corneum (EC) , which allows the use of these systems as permeation enhancers of NFD.As micelas (MIs) e as microemulsões (MEs) são classificadas como sistemas estabilizados por tensoativos e se assemelham bastante com relação a sua estrutura e propriedades físico-químicas. Quanto a sua aplicabilidade, elas têm sido destacadas por serem capazes de veicular fármacos que possuem uma biodisponibilidade sistêmica limitada por via oral. A formação destes sistemas é dependente principalmente dos tipos de componentes utilizados, tornando-se relevante o estudo da sua influência na estrutura. O objetivo do presente trabalho foi a obtenção e caracterização de sistemas micelares e microemulsionados (contendo óleo essencial de Citrus sinensis (L.) Osbeck como fase oleosa), estabilizados por um tensoativo não iônico (Tween 80) e um cotensoativo de cadeia curta (álcool etílico), que possam ser utilizados como sistema de liberação para a nifedipina (NFD, um fármaco modelo), buscando verificar a influência das fases e a interação do fármaco na estrutura desses sistemas. Diagramas de fase ternário e pseudoternário para MIs e MEs, respectivamente, foram obtidos e a partir das regiões de formação, formulações foram selecionadas para caracterização físico-química e incorporação da NFD. Os aspectos macro e microscópicos foram avaliados utilizando microscopia de luz polarizada (MLP), medidas de pH, condutividade elétrica e tensão superficial. O tamanho médio de gotículas foi avaliado por espalhamento dinâmico de luz (DLS) e espalhamento de raios-x a baixos ângulos (SAXS). Os resultados demonstraram que esses sistemas são estáveis, isotrópicos e opticamente transparentes na ausência e presença de fármaco. O tamanho das gotículas diminuiu com o aumento da quantidade de tensoativo para as MIs e de mistura de tensoativo/cotensoativo para as MEs. A influência do cotensoativo nas MIs foi praticamente desprezível. O aumento da quantidade de fase oleosa nas MEs ocasionou um aumento do tamanho das gotículas. A presença da NFD não exerceu influência na estrutura das MIs, entretanto para as MEs aumentou o tamanho de gotículas, sugerindo que a NFD se encontra na fase interna das MEs. Os modelamentos das curvas de SAXS para as MIs e MEs mais diluídas foram realizados e mostraram a interação existente entre a NFD e os sistemas, corroborando com os resultados anteriores. Estudos por espectrofotometria de absorção na região do infravermelho com transformada de Fourier (FTIR) comprovaram a interação das MIs e das MEs com o estrato córneo (EC), o que possibilita o uso destes sistemas como promotores de permeação da NFD.