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Vilken reparationstejp bör företag erbjuda? : En studie riktad mot textilföretag med cirkulär ekonomi / Which repair tape should companies offer?Hjälmeby, Sara, Holmdahl, Sarah January 2018 (has links)
Allt fler företag går i dagsläget från en linjär till en cirkulär ekonomi med hjälp av implementering av hållbarhetsstrategier. I och med att allt fler företag börjar använda sig av en cirkulär ekonomi har inte alla områden hunnit utvecklats med det. Ett område som är outforskat är reparationsmaterial, som används av företag eller konsumenter som vill reparera deras kläder. I den här studien har tre reparationstejper som existerar på marknaden applicerats på skalmaterial för att studera och kartlägga vilken av dessa som har längst hållfasthet. Studien kommer även att behandla vilken av dessa reparationstejper som lämpar sig för en cirkulär ekonomi. Detta då företag ska kunna erbjuda en reparationstejp som går i enlighet med detta. Reparationstejperna genomgick fyra olika tester för att testa dess vidhäftningsstyrka, dessa är tvätt-test, vidhäftningstest, dragprovning samt nötningstest. Resultaten utifrån dessa tester visade på att Gore-Tex var den reparationstejp som hade bäst hållfasthet på skalmaterialet. Däremot visade det sig att Tesa Eco Repair var mest lämpad för cirkulär ekonomi, även om Gore-Tex också visade sig kunna ingå i ett slutet system. Gorilla-tejpens vidhäftningsstyrka var bättre än Tesa Eco Repair men eftersom underlag saknas för att ta ställning till om den lämpar sig för cirkulär ekonomi eller inte, går det inte ta ställning till detta. Denna studie ämnar att rikta sig till företag som vill implementera ett reparationskit eller undersöka vilka reparationsmöjligheter det kan tänkas finnas för både företag och konsumenter. Den kan även finnas som riktlinje för företag som vill erbjuda reparationstejper i sin verksamhet men även för produktutveckling av en reparationstejp som ingår i en cirkulär ekonomi. Den här studien kan spela en stor roll för samhället och företag. Detta då den ger riktlinjer som behövs tas för att följa med i den pågående trend vad det gäller cirkulär ekonomi och hållbar konsumtion. / In the world today, more companies go from a linear economy to a circular economy by implementing sustainability strategies. As more and more companies begin to use a circular economy, not all areas have developed with it. One area that is unexplored is repair material that companies and consumers use if they want to repair their clothes. In this study, three repair tapes that exist on the market Gore-Tex, Tesa Eco Repair, and Gorilla-tape were applied to shell material to examine and map which one of them is the strongest and most durable. This study is also going to discuss which one of the repair tapes is most suitable for a circular economy. This is because companies should be able to offer one repair tape that fits in an circular economy. The repair tapes were examined through four different experiments to test their adhesion strength including: the laundry test, adhesion test, tensile testing, and abrasion test. The conclusions drawn from these tests showed that Gore-Tex was the strongest repair tape on the shell material. However, the tests also showed that Tesa Eco Repair was most suitable for a circular economy even though Gore-Tex proved to be part of a circular economy. The Gorilla-tape adhesive was stronger than Tesa Eco Repair but since there is no basis for determining whether it is suitable for circular economy or not, it can not be taken into account. This study is directed to companies that want to implement a repair-kit or investigate what repair opportunities they have, both for companies and consumers. It will serve as a guideline for companies that want to offer repair services in their operation but also for product development of a repair program that can be successful in a circular economy. The study can play a major role for in society and company development as it will give them guidelines on the ongoing trend of circular economies and sustainable consumption.
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Utformning av ett verktyg för att nå cirkulära lösningar i byggprojekt : Implementering av cirkulär ekonomi på företaget Incoord / Development and design of a tool for reaching circular solutions in construction projectsKristoffersson, Agnes, Koch, Johanna January 2018 (has links)
This master thesis aims to create a user-friendly Excel-based tool tohelp the co-workers at Incoord, a technology consulting companywithin the construction business, to implement circular economy intheir projects. A literature study was done focusing on theconstruction business, circular economy and earlier implementedcircular projects and user-design experience. Interviews were heldwith the co-workers at Incoord to identify where and how circulareconomy can be implemented in the projects at Incoord. In addition,workshops and a case-group meeting were held with the co-workers toset up the requirement specifications for user-design experience andto encourage the co-workers to come up with circular solutions. All of this resulted in a framework that included knowledge aboutuser-design experience and questions encouraging circular solutionsin the projects at Incoord. The framework was used when the digitaltool was created in Excel. The tool was evaluated to make sure thatit met the requirement specifications. It resulted in a toolconsisting of four parts; the first focusing on circular solutionsthat can be made by Incoord themselves, the second advocated toexternal actors, the third focusing on promoting circular materialand the fourth calculating the carbon dioxide reduction whenreprocessing compared to making new materials. The different partscan be adjusted depending on which area of expertise the user isworking within. Points are collected depending on the answers in thedifferent parts, which gives the user a concluding result that showshow circular the current project can be.
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Exploring opportunities for the improvement of recycling behaviours in universities : The case of the Blåsenhus campus of Uppsala UniversityHureau, Alexandre January 2018 (has links)
As the environmental footprint of humans continue s to grow, and the amount of easily available resources keeps dwindling, many countries and institutions have turned towards the concept of circular economy as a way of diminishing their impact on the environment. Based in the idea of closing the resource loop by reducing the need for new resources, increasing efficiency, and reusing resources that are already extracted, many efforts have gone towards transforming our sys tem towards a circular economy. Unfortunately, recycling, identified as a vital part of the move towards circular economy, has been found to be less than optimal in many countries, despite efforts to improve the system. This study examines methods of improving environmental and recycling behaviour in the context of a university setting, the Blåsenhus campus of Uppsala University. Identifying barriers to remove and incentives to apply through a series of focus groups, this study then runs a trial period wher e measures are implemented. These include ads on the campus’ monitors, as well as posters indicating the benefits of recycling, as well as the impacts of failing to do so, information sheets clearly indicating how to recycle the most commonly misplaced ite ms, and the movement of certain bins to make recycling easier to access in relation to the burnables bins. The findings of this study are that the combined use of barrier removal along with the implementation of incentives, can be beneficial to the rates at which waste is recycled.
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A influência do peso molecular do PEG na transição-Ψ multimolecular do DNARamos Junior, José Ésio Bessa [UNESP] 13 May 2004 (has links) (PDF)
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Contribuição eletrostática e não eletrostática na interação de peptídeos líticos com membranas modeloLeite, Natália Bueno [UNESP] 31 August 2010 (has links) (PDF)
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leite_nb_me_sjrp.pdf: 1707233 bytes, checksum: a9b663e6312a6e9e7f0d5b241ce03ac1 (MD5) / Peptídeos bioativos são de elevado interesse como substitutos de antibióticos convencionais já que alguns destes apresentam atividade antimicrobiana. Eles são predominantemente catiônicos e tem sido mostrado que sua atividade antimicrobiana é modulada por interações eletrostáticas, hidrofóbicas e por características elásticas das membranas, seu alvo. Neste trabalho analisou-se a importância da carga elétrica líquida (Q) e hidrofobicidade na interação de quatro peptídeos com membranas modelo de caráter aniônico e zwitteriônico utilizando medidas de potencial eletrocinético, dicroísmo circular e espectroscopia de fluorescência. Estes peptídeos denominados mastoparanos apresentam carga liquida de +1 a +4, devido à presença de resíduos ácidos e básicos, foram extraídos do veneno de vespas, três dos quais de espécie nativa da bodiversidade nacional, mostraram intensa atividade antimicrobiana. Nos peptídeos com Q = +1 e +2 predomina o caráter hidrofóbico enquanto nos demais o caráter hidrofílico; o peptídeo com Q = +4 tem sua estrutura resolvida por NMR e devido à alta homologia entre essa seqüência e dos demais se supõe que eles também sejam anfipáticos. A atividade lítica é caracterizada por uma razão [P]/[L] crítica entre as concentrações totais de peptídeo e lipídeo, acima da qual ocorre um processo cooperativo de liberação de corante do interior das vesículas. A razão crítica, a eficiência do vazamento e a cooperatividade mostraram ser dependentes na densidade superficial de carga da vesícula e da carga liquida do peptídeo. Observaram-se razões [P]/[L] críticas da ordem de sub-micromolar tanto em vesícula zwitteriônica quanto em vesícula aniônica. As curvas dose-resposta tornaram-se menos cooperativas com o aumento da carga líquida dos peptídeos, mostrando que a razão crítica aumenta com a carga. Os espectros... / Bioactive peptides are of high interest as substitutes of conventional antibiotics since some of them present antimicrobial action. They are predominantly cationic and it has been shown that their antimicrobial activity is modulated by electrostatic interactions, hydrophobic contributions and the elastic features of the membranes they target. In this work we analyzed the importance of charge and hidrofobicity to the interaction of four peptides with anionic and zwitterionic model membranes using electrokinetics potential, circular dicrohism and fluorescence spectrsocopy. These peptides named mastoparans, have exhibit a net charge ranging from +1 to +4 due to the presence of acidic and basic residues, and three of them, extracted from the venom of wasps native of the brazilian biodiversity showed intense antibacterial activity. The peptides with Q= +1 and +2, are hydrophobic and the other two are hydrophilic. Lytic activity of peptides, accessed by the release of fluorescent dye entrapped in lipid vesicles, showed sigmoid dose-response curves either in zwitterionic or in anionic vesicles with sub-micromolar threshold ratios. The lytic activity was characterized by a threshold [P]/[L] value, above which cooperative dye release takes place. The threshold ratio, the leakage efficiency and cooperativity were found to be dependent on the vesicle surface charge density and on the peptide net charge. Roughly the threshold ratios increase with the peptide net charge and as the net charge increases the dose response curves become less cooperative. Circular dichroism spectra of the peptides in vesicles exhibit two negative dichroic bands at 222 and 208 nm characteristic of helical structure, while they were observed to be random coil in buffer. At peptide and lipid concentrations near the threshold ratio the CD spectra have the... (Complete abstract click electronic access below)
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Avalia??o estrutural e an?lise das atividades biol?gicas de pept?deos an?logos da stigmurina presente na pe?onha do escorpi?o Tityus stigmurusParente, Adriana Marina e Silva 28 November 2017 (has links)
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Previous issue date: 2017-11-28 / Tityus stigmurus corresponde ? esp?cie de escorpi?o predominante na regi?o Nordeste do Brasil, sendo considerado um dos principais causadores de acidentes escorpi?nicos. Na pe?onha do T. stigmurus, que ? composta de uma mistura complexa de mol?culas de alta e baixa massa molecular, foi identificado e caracterizado um pept?deo antimicrobiano denominado Stigmurina (FFSLIPSLVGGLISAFK-NH2). Pept?deos antimicrobianos s?o pequenas mol?culas consideradas a primeira linha de defesa contra micro-organismos, apresentando amplo espectro de a??o antimicrobiana. A literatura reporta tamb?m a atividade desses pept?deos contra c?lulas cancer?genas. Sequ?ncias nativas de pept?deos bioativos como prot?tipo para a obten??o de novas mol?culas t?m sido utilizadas com o intuito de potencializar a sua atividade e reduzir a toxicidade. Nesse contexto, realizou-se a caracteriza??o estrutural in silico e por dicro?smo circular, bem como a avalia??o da atividade antimicrobiana, antiparasit?ria, antiproliferativa e hemol?tica de dois pept?deos an?logos obtidos ? partir da Stigmurina, denominados StigA3 e StigA4. A an?lise da conforma??o tridimensional in silico do StigA3 e StigA4 demonstrou uma estrutura helicoidal, sendo este resultado confirmado por dicro?smo circular. O aumento da carga superficial e do momento hidrof?bico de ambos os pept?deos an?logos quando comparado com a Stigmurina resultaram na potencializa??o da atividade antimicrobiana e antiparasit?ria. Os pept?deos StigA3 e StigA4 apresentaram a??o antiproliferativa semelhante ao pept?deo nativo, com exce??o para a c?lula normal, para qual os pept?deos an?logos se mostraram menos t?xicos. Portanto, estes resultados indicam uma potencial aplica??o terap?utica destes pept?deos an?logos, demonstrando a efici?ncia do desenho racional de f?rmacos para a obten??o de novos agentes antiproliferativos e anti-infecciosos. / Tityus stigmurus it?s the predominant scorpion specie in Northeast region from Brazil, it?s considered one of the main cause of scorpion accidents in this region. In T. stigmurus venom, which is a complex mixture of high and low molecular mass molecules, was identified an antimicrobial peptide denominated Stigmurin. Antimicrobial peptides are small molecules considered the first line of defense against microorganisms, they show broad spectrum action. Many authors have proved that these peptides can also be effective on cancerous cells. Mutation in these molecules sequence has been held aiming the increase in the activity maintaining its low toxicity. Therefore, it is proposed the characterization of the structure in silico and by circular dichroism, as well the antimicrobial, antiparasitic, anti-proliferative and hemolytic activities of two analog peptides from Stigmurin, denominated StigA3 and StigA4. We performed an in silico analysis for these peptides, where we were able to observe ?-helix structure, which was confirmed by circular dichroism. We were also able to find that the analog peptides net charge and hydrophobic moment were higher than Sitgmurin?s, which can explain the increase in antimicrobial and antiparasitic activity. The peptides StigA3 e StigA4 showed activity on cancerous cells similiar to the native peptide, except when tested on a normal cell we were able to find that they?re less toxic. Therefore, these results indicate a potential biotechnological application for the analogs peptides, even as prototype to new therapeutic agents.
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Beyond Recycling: Design for Disassembly, Reuse, and Circular Economy in the Built EnvironmentJanuary 2018 (has links)
abstract: Today, we use resources faster than they can be replaced. Construction consumes more resources than any other industry and has one of the largest waste streams. Resource consumption and waste generation are expected to grow as the global population increases. The circular economy (CE) is based on the concept of a closed-loop cycle (CLC) and proposes a solution that, in theory, can eliminate the environmental impacts caused by construction and demolition (C&D) waste and increase the efficiency of resources’ use. In a CLC, building materials are reused, remanufactured, recycled, and reintegrated into other buildings (or into other sectors) without creating any waste.
Designing out waste is the core principle of the CE. Design for disassembly or design for deconstruction (DfD) is the practice of planning the future deconstruction of a building and the reuse of its materials. Concepts like DfD, CE, and product-service systems (PSS) can work together to promote CLC in the built environment. PSS are business models based on stewardship instead of ownership. CE combines DfD, PSS, materials’ durability, and materials’ reuse in multiple life cycles to promote a low-carbon, regenerative economy. CE prioritizes reuse over recycling. Dealing with resource scarcity demands us to think beyond the incremental changes from recycling waste; it demands an urgent, systemic, and radical change in the way we design, build, and procure construction materials.
This dissertation aims to answer three research questions: 1) How can researchers estimate the environmental benefits of reusing building components, 2) What variables are susceptible to affect the environmental impact assessment of reuse, and 3) What are the barriers and opportunities for DfD and materials’ reuse in the current design practice in the United States.
The first part of this study investigated how different life cycle assessment (LCA) methods (i.e., hybrid LCA and process-based LCA), assumptions (e.g., reuse rates, transportation distances, number of reuses), and LCA timelines can affect the results of a closed-loop LCA. The second part of this study built on interviews with architects in the United States to understand why DfD is not part of the current design practice in the country. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2018
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On-line Coloring of Partial Orders, Circular Arc Graphs, and TreesJanuary 2012 (has links)
abstract: A central concept of combinatorics is partitioning structures with given constraints. Partitions of on-line posets and on-line graphs, which are dynamic versions of the more familiar static structures posets and graphs, are examined. In the on-line setting, vertices are continually added to a poset or graph while a chain partition or coloring (respectively) is maintained. %The optima of the static cases cannot be achieved in the on-line setting. Both upper and lower bounds for the optimum of the number of chains needed to partition a width $w$ on-line poset exist. Kierstead's upper bound of $\frac{5^w-1}{4}$ was improved to $w^{14 \lg w}$ by Bosek and Krawczyk. This is improved to $w^{3+6.5 \lg w}$ by employing the First-Fit algorithm on a family of restricted posets (expanding on the work of Bosek and Krawczyk) . Namely, the family of ladder-free posets where the $m$-ladder is the transitive closure of the union of two incomparable chains $x_1\le\dots\le x_m$, $y_1\le\dots\le y_m$ and the set of comparabilities $\{x_1\le y_1,\dots, x_m\le y_m\}$. No upper bound on the number of colors needed to color a general on-line graph exists. To lay this fact plain, the performance of on-line coloring of trees is shown to be particularly problematic. There are trees that require $n$ colors to color on-line for any positive integer $n$. Furthermore, there are trees that usually require many colors to color on-line even if they are presented without any particular strategy. For restricted families of graphs, upper and lower bounds for the optimum number of colors needed to maintain an on-line coloring exist. In particular, circular arc graphs can be colored on-line using less than 8 times the optimum number from the static case. This follows from the work of Pemmaraju, Raman, and Varadarajan in on-line coloring of interval graphs. / Dissertation/Thesis / Ph.D. Mathematics 2012
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"Purificação, caracterização e estudos estruturais de duas lectinas ligantes de quitina das sementes do gênero Artocarpus" / Purification, Characterization and Structural Studies of Two Novel Chitin-Binding Lectins from the Seeds of Artocarpus GenusMelissa Barbano Trindade 29 April 2005 (has links)
Este trabalho trata da purificação em escala preparativa por técnicas cromatográficas, determinação de seqüência primária parcial, caracterização espectroscópica por dicroísmo circular, fluorescência, infravermelho e investigação de atividades biológicas de duas lectinas ligantes de quitina dos extratos salinos de Artocarpus integrifolia, jaca, e Artocarpus incisa, fruta-pão. Nossos resultados revelaram que as lectinas quitina-ligantes das sementes de jaca e fruta-pão, jackina e frutackina respectivamente, são homólogas entre si, constituindo-se por monômeros de cerca de 14 kDa formados por três subunidades, unidas por pontes S-S. Elas possuem 62% de identidade entre si, são ricas em cisteínas, aminoácidos básicos e serinas e não possuem similares identificadas até o momento, podendo constituir um novo grupo de lectinas na superfamília de lectinas quitina-específicas. Os espectros de dicroísmo circular de jackina e frutackina são similares: ambas são proteínas de estrutura toda-beta, com máximo em torno de 230 nm e mínimo em torno de 214 nm, este último, bastante distorcido por estruturas desordenadas. Os espectros de fluorescência de jackina e frutackina apresentaram máximos de emissão acima de 340 nm, sugerindo que os N-terminais de duas das 3 cadeias de jackina e frutackina (onde os triptofanos estão localizados) estão expostos. Frente a condições extremas de pH e temperatura, monitoradas por CD e fluorescência, observou-se que a estrutura de jackina é vulnerável a pH ácido e termicamente estável. Quanto às atividades biológicas, jackina e frutackina mostraram atividade inibitória de crescimento para Saccharomyces cerevisiae; jackina também mostrou promoção de adesão da linhagem de células de eritroleucemia K562, atividade inibitória para Fusarium moniliforme na concentração de 2,25 mg/mL e atividade hemaglutinante frente a células sangüíneas humanas do sistema ABO e de coelhos, que não foi inibida nem por N-acetilglicosamina, indicando sua preferência por quitina ou seus fragmentos. / This work deals with the preparative-scale purification by chromatographic techniques, the partial primary sequence determination, the spectroscopic characterization by circular dichroism, fluorescence, FT-IR and the investigation of biological activities of two novel chitin-binding lectins from the saline extracts of the seeds of Artocarpus integrifolia, jackfruit, and Artocarpus incisa, breadfruit. Our results revealed that the chitin-binding lectins from jackfruit and breadfruit, jackin and frutackin respectively, are homologous to each other, consiting of monomers of 14 kDa, made up of 3 subunits, linked by S-S bridges. They have 62% of identity between each other; they are rich in cysteines, serines and basic amino acids and they are no homologous to any other known protein, probably constituting a new group of lectins in the chitin-binding lectin superfamily. The CD spectra of jackin and frutackin are similar: both present a beta profile spectra, presenting a maximum about 230 nm and a minimum around 214 nm, this later one, distorted by unordered structures. The fluorescence spectra of jackin and frutackin presented maxima above 340 nm, suggesting that the N-terminals of the 2 up 3 chains of jackin and frutackin (where the tryptophans are) are exposed. Regarding the pH and temperature exposure, monitored by CD and fluorescence, it was observed that the structure of jackin is vulnerable to acid pH and thermally stable. When considered the biological activities, jackin and frutackin presented growth inhibition activity towards Saccharomyces cerevisiae; jackin also promoted the adhesion of the erythroleukemic cell line K562, presented growth inhibition activity towards Fusarium moniliforme at 2,25mg/mL and hemaggluting activity towards rabbit and human red cells from the system ABO, that was not inhibited even by N-acetilglucosamine, suggesting itspreference by oligomers of N-acetilglicosamine or chitin.
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Assimetrias interlaterais na coordenação interarticular de movimentos manuais circulares cíclicos / Interlateral asymmetries in interjoint coordination on cyclic circular manual movementsCarla Ferro Pereira 30 March 2011 (has links)
A dominância lateral para controle motor tem sido proposta ser devida a uma capacidade superior em lidar com a dinâmica do movimento com o hemisfério/lado corporal dominante. A partir desta hipótese, é esperado que o braço dominante apresente tanto trajetórias mais precisas quanto modos de coordenação mais estáveis. Além disso, tal assimetria motora deveria ser mais evidente em movimentos mais rápidos. No presente estudo foi avaliada a assimetria interlateral de desempenho na coordenação interarticular/ intramembro em movimentos realizados em diferentes frequências. Foi analisada a coordenação interarticular entre o ombro e o cotovelo do mesmo braço em uma tarefa de realizar movimentos circulares com as mãos, comparando o desempenho entre os braços dominante e não-dominante. O estudo foi realizado com 16 adultos jovens, que realizaram a tarefa em cinco frequências de movimento, variando de 40% a 100% da frequência individual máxima. Movimentos angulares das articulações foram analisados através de marcadores refletivos fixados no ombro, cotovelo e punho de ambos os braços. Os marcadores foram rastreados automaticamente por meio de um sistema optoeletrônico, com frequência de aquisição de 240 Hz, e análise em 3D. Os resultados demonstraram que o desempenho com o braço não-dominante apresentou as seguintes diferenças em comparação com o braço dominante: trajetória da mão e amplitudes angulares mais variáveis, maior participação do cotovelo, coordenação em modo antifase (braço dominante: relação de fase de aproximadamente 120º) e maior variabilidade de modo de coordenação. De forma geral, as assimetrias interlaterais foram acentuadas em frequências de movimento mais altas. Estes resultados indicam que a vantagem de desempenho com o braço dominante é devida a um modo de coordenação mais consistente e efetivo em realizar a trajetória desejada / Lateral dominance for motor control has been proposed to be due to a superior capacity to deal with motion dynamics with the dominant cerebral hemisphere/body side. From this conjecture, it is expected the dominant arm to present both an increased capacity to perform more accurate trajectories and a more stable interjoint coordination. Moreover, such motor asymmetry should be more evident in fast movements. We assessed interjoint coordination between the shoulder and the elbow on a circle drawing task, comparing performance between the dominant and the non-dominant arm. The study was conducted with 16 young adults, who performed the task on five movement frequencies, ranging from 40% to 100% of the individual maximum. Angular motion of the joints was recorded through reflective markers attached at the shoulder, elbow and wrist of both arms. Markers were tracked automatically by using an optoelectronic system, with data sampling frequency set at 240 Hz, and 3D analysis. The results showed that performance with the non-dominant arm had the following differences in comparison with the dominant arm: more variable hand trajectory and joint amplitudes, interjoint coordination in antifase (dominant arm: phase relation of approximately 120º) and increased variability in the coordination mode. Overall, interlateral asymmetries were amplified in higher movement frequencies. These results indicate that the advantage of the dominant arm resides in a more stable and effective mode of coordination in performing the desired trajectory
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