[pt] Neste trabalho aplicamos o método RPA renormalizada ao modelo de Hubbard estendido para a cadeia unidimensional com preenchimento meio. Inicialmente verificamos a inúncia do termo de interação entre primeiros vizinhos, V , nas susceptibilidades de carga e longitudinal de spin e comparamos com os resultados de Hubbard puro. Para pequenas interações entre os primeiros vizinhos, a influência de V é muito pequena. À medida que V cresce, seu efeito é de diminuir a frequência dos plasmons e dificultar o aparecimento de magnons. Em seguida determinamos as susceptibilidades de spin e de carga, numericamente, para U = 3,4 e 5 com V entre 0 e próximo de U. Partindo da fase de onda de densidade de spin (SDW) e quando V cresce, o pico de plasmon na susceptibilidade de cargas em 2kF se aproxima de ômega = 0, indicando uma instabilidade para formação de uma onda de densidade de carga (CDW). Isto permite determinar a fronteira de separação entre as duas fases. De acordo com a RPA convencional, esta transformação ocorre em U = 2V mas o processo de renormalização desloca esta fronteira ligeiramente para o interior da região da fase CDW, em conformidade com outros métodos que não fazem a aproximação de campo médio. / [en] In this work we apply the Random Phase Approximation (RPA) to the Extended Hubbard Model in one dimension. Initially we investigate the effect of the first neighbor interaction term, V , on the spin and charge susceptibilities. When V is small, its influence is also very small but as it grows, it tends to lower the plasmon frequency and to inhibit the condition for the existence of magnons. We also have calculated numerically both the spin and the charge susceptibilities for U = 3,4 and 5 with V in the region (0; U). Starting from the SDW region and increasing V we found that the plasmon peak in the charge susceptibility for 2kF tends to omega = 0, indicating an instability against the formation of a CDW ground state. This allows us to determine the phase separation line between the two phases. According to the conventional RPA, this transition occurs for U = 2V but due to the renormalization process, we nd that this frontier shifts slightly to the interior of the CDW region, in agreement with methods not using the mean eld approximation.

Organisationer blir allt mer beroende av digitala lösningar i den dagliga verksamheten för att upprätthålla konkurrensen gentemot andra företag. Under en längre tid har organisationer implementerat Enterprise Resource Planning (ERP) system för att effektivisera verksamheterna och öka konkurrensfördelarna. I takt med utvecklingen av digitala lösningar har begreppet Robotic Process Automation (RPA) växt fram. RPA implementeras för att automatisera och effektivisera organisationers affärsprocesser. Likt implementering av ERP-system finns det utmaningar kopplade till implementering av RPA som behöver hanteras för att minska kostnader och öka effektiviteten. Tidigare forskning som identifierats har undersökt utmaningar vid implementering av RPA utifrån kundens och projektets perspektiv. Däremot har tidigare forskning som identifierats inte undersökt eller behandlat utmaningar utifrån RPA-leverantörens perspektiv, vilket resulterade i studiens syfte och undersökningsområde. Syftet med studien är att undersöka och kartlägga utmaningar som RPA-leverantörer kan ställas inför vid implementering av RPA. För att besvara frågeställningen och erhålla en djupare förståelse kring undersökningsområdet har nio RPA-konsulter intervjuats. Studiens resultat påvisar att kartlagda utmaningar utifrån RPA-leverantörens perspektiv vid implementering av RPA både skiljer sig och överensstämmer med utmaningar som identifierats i litteraturstudien utifrån projektets och kundens perspektiv. I slutsatsen presenteras elva utmaningar som RPA-leverantörer kan ställas inför vid implementering av RPA. / Organizations are becoming more dependent on using digital solutions in their daily operations to stay competetive with other companies. Organizations have implemented Enterprise Resource Planning (ERP) systems for a long time to streamline operations and increase competitive advantages. Along with the development of digital solutions, the concept of Robotic Process Automation (RPA) has developed. RPA is implemented to automate and streamline the organization's business processes. As an implementation of ERP systems, there are challenges associated with the RPA implementation that must be addressed to reduce costs and increase efficiency. Previous research that has been identified has investigated challenges with implementing RPA from a customer and project perspective. However, previous identified research has not investigated or mapped the challenges from the perspective of the RPA supplier, which resulted in the study's purpose and area of ​​study. The purpose of the study is to investigate and map the challenges that RPA suppliers may face when implementing RPA. To answer the question of the study and gain a deeper understanding of the study area, nine RPA consultants were interviewed. The result from the study demonstrates that mapped challenges from the RPA supplier perspective both differ and confirm challenges identified in previous research from a customer and project perspective. The conclusion presents eleven challenges that RPA suppliers may face when implementing RPA.

La recombinaison homologue est un processus conservé chez les eucaryotes. Au cours de la méiose,ce mécanisme est essentiel à la formation des crossing-overs, eux-mêmes essentiels à la bonne ségrégation des chromosomes homologues. La recombinaison méiotique est assurée par l’action combinée de facteurs mitotiques et méiotiques. La protéine MEIOB a récemment été identifiée et caractérisée comme étant essentielle à la réparation des cassures double brin de l’ADN au cours de la méiose. MEIOB est un paralogue de RPA1, la grande sous-unité du complexe RPA qui est un complexe de liaison à l’ADN simple brin ubiquitaire et composé de RPA1, RPA2 et RPA3. MEIOB peut interagir avec SPATA22 et RPA2. Cette observation suggère que MEIOB, SPATA22 et RPA pourraient agir ensemble au cours de la recombinaison méiotique. En se basant sur l’homologie de structure entre MEIOB, SPATA22 et les sous-unités de RPA, nous avons caractérisé les modalités et le rôle de leur interaction. Nous avons montré que MEIOB et SPATA22 interagissent grâce à leur domaines OB-folds C-terminaux à l’image de RPA1 et RPA2 et que MEIOB et SPATA22 coopèrent pour interagir avec le complexe RPA. Par microscopie électronique, nous avons mis en évidence que la présence de MEIOB-SPATA22 induit une forte condensation du filament RPA ADN simple brin. Nous avons également montré par immunofluorescence sur chromosomes méiotiques murins que l’hélicase BLM accumule sur les axes chromosomiques et que cette accumulation est corrélée avec l’élimination de la recombinase DMC1 des cassures méiotiques non-réparées, en absence de MEIOB. Enin, nous avons mis en évidence par microscopie à haute résolution que l’absence de MEIOB favorise une distribution anormale des protéines recombinases. Nos résultats suggèrent que MEIOB, SPATA22 et RPA collaborent pour assurer l’intégrité des intermédiaires de recombinaison méiotiques au cours de l’invasion d’un brin homologue. / Homologous recombination is a conserved process among eukaryotes. During meiosis, thismechanism is essential to the formation of crossovers and thus for the proper segregation of chromosomes. Meiotic recombination is ensured by the combined action of mitotic and meiotic factors. MEIOB has been recently identiied and shown to be essential to the repair of meiotic DNA double-strand breaks. MEIOB is aparalog of RPA1, the large subunit of RPA, which is a ubiquitous ssDNA-binding trimeric composed ofRPA1, RPA2 and RPA3. MEIOB has been shown to interact with SPATA22 and RPA2. This observation suggested that MEIOB, SPATA22 and RPA may work together. Based on the homology existing betweenstructural domains of MEIOB, SPATA22 and the RPA subunits, we deciphered the modality and the role oftheir interactions. We show that MEIOB and SPATA22 interact through their C-terminal OB domains like RPA1 and RPA2 and cooperate to interact with the RPA complex. Using Transmission Electron Microscopy,we evidenced that the presence of MEIOB/SPATA22 induces a strong compaction of the RPA/ssDNAilament. Immunofluorescent microscopy performed on murin meiotic chromosomes revealed that in theabsence of MEIOB, the BLM helicase accumulates on chromosomes axis and correlates with the eviction ofthe DMC1 recombinase from unrepaired meiotic breaks. Finally, we show that the absence of MEIOB favorsabnormal recombinase distribution observed by SIM microscopy. Together, our results evidence thatMEIOB, SPATA22 and RPA act together to insure the integrity of recombination intermediates during strandinvasion.

O complexo telomérico, responsável pela integridade genômica, é formado pela interação de DNA com proteínas, que são responsáveis pela proteção desses terminais. O complexo RPA de eucariotos compreende um heterotrímero, que cumpre diversas funções vitais na célula, sendo uma peça fundamental na replicação, reparo e recombinação. A ausência de homólogos de proteínas que protegem o telômero em T. cruzi nos fez investigar se o complexo RPA poderia cumprir essa função. Assim, este trabalho teve como objetivo caracterizar a interação TcRPA-1-telômero. Conseguimos verificar a interação in vitro e in vivo da RPA-1 com o telômero em epimastigotas e tripomastigotas. A ausência de homólogos de proteínas que interagem com o overhang telomérico em tripanosomas, a interação específica RPA-1-telômero, e a sua presença nos telômeros da forma de vida não replicativa, bem como as peculiaridades estruturais da TcRPA-1, levam-nos a propor que essa proteína pode estar envolvida com a proteção dos telomérica neste organismo. / The telomeric complex, responsible for genomic integrity and stability , is formed by the interaction of DNA with proteins that are responsible for maintaining and protecting these terminals. The eukaryotic RPA complex comprises a heterotrimer, which fulfills several vital functions in the cell , being a fundamental player in replication , repair and recombination. The absence of homologous proteins that protect telomeres in Trypanosoma cruzi lead us to hypothesize that RPA complex could fulfill this function. Thus, this study aimed to characterize TcRPA-1-telomere interaction. We could verify in vitro and in vivo interaction of RPA - 1 with telomeres in epimastigote and trypomastigote lifeforms. The absence of homologs of proteins that interact with telomeric overhang in trypanosomes, the specific interaction RPA-1- telomere , its presence in non- replicative lifeform as well as structural peculiarities of TcRPA-1, lead us to propose that this protein may be involved in telomere protection in this organism.

O complexo telomérico, responsável pela integridade genômica, é formado pela interação de DNA com proteínas, que são responsáveis pela proteção desses terminais. O complexo RPA de eucariotos compreende um heterotrímero, que cumpre diversas funções vitais na célula, sendo uma peça fundamental na replicação, reparo e recombinação. A ausência de homólogos de proteínas que protegem o telômero em T. cruzi nos fez investigar se o complexo RPA poderia cumprir essa função. Assim, este trabalho teve como objetivo caracterizar a interação TcRPA-1-telômero. Conseguimos verificar a interação in vitro e in vivo da RPA-1 com o telômero em epimastigotas e tripomastigotas. A ausência de homólogos de proteínas que interagem com o overhang telomérico em tripanosomas, a interação específica RPA-1-telômero, e a sua presença nos telômeros da forma de vida não replicativa, bem como as peculiaridades estruturais da TcRPA-1, levam-nos a propor que essa proteína pode estar envolvida com a proteção dos telomérica neste organismo. / The telomeric complex, responsible for genomic integrity and stability , is formed by the interaction of DNA with proteins that are responsible for maintaining and protecting these terminals. The eukaryotic RPA complex comprises a heterotrimer, which fulfills several vital functions in the cell , being a fundamental player in replication , repair and recombination. The absence of homologous proteins that protect telomeres in Trypanosoma cruzi lead us to hypothesize that RPA complex could fulfill this function. Thus, this study aimed to characterize TcRPA-1-telomere interaction. We could verify in vitro and in vivo interaction of RPA - 1 with telomeres in epimastigote and trypomastigote lifeforms. The absence of homologs of proteins that interact with telomeric overhang in trypanosomes, the specific interaction RPA-1- telomere , its presence in non- replicative lifeform as well as structural peculiarities of TcRPA-1, lead us to propose that this protein may be involved in telomere protection in this organism.

The objective of this thesis paper is to answer the question: is robotic process automation efficient/beneficial and should accountants consider its implementation? For accountants, robotic process automation is a software that “perform[s] tasks such as processing sales and financial transactions, managing data, communicating between different systems, and access management, as well as monitoring and reporting” (Seasongood, 2016). In order to determine whether or not RPA should be implemented, a survey was found that had over 500 responses from varying companies currently using RPA. A statistical analysis will be performed in order to determine if any statistical significances exist between questions (both the benefits and challenges of RPA), by countries, by employee sizes, and by business functions. Based on the results, a conclusion will be provided on RPA’s implementation into the accounting field.

Det är allt vanligare att organisationer och dess processer genomgår en digital transformation föratt uppnå konkurrensfördelar. Organisationer letar ofta efter effektivare sätt att utföra processer.För att effektivisera processer kan digitala verktyg som Robotic Process Automation (RPA)användas. RPA har under de senaste fem åren blivit populärt bland organisationer då RPA oftastger en snabb return on investment (ROI). Vid ett strukturerat införande av RPA i organisationerkrävs ett förändringsarbete då det kan uppstå utmaningar som behöver hanteras. Befintliglitteratur inom RPA-området beskriver olika typer av metoder och utmaningar vid införande avRPA, men lite är känt om hur utmaningar och förändringar påverkar RPA-införandet och när deförekommer. Studiens syfte är därför att identifiera vilka utmaningar som uppkommit vidinförandet och när de förekommer. Studiens frågeställning lyder: Vilka utmaningar iförändringsarbetet finns det vid införande av RPA? Studien visar att utmaningar som uppkommer bör hanteras i tid för att inte påverka senareaktiviteter i RPA-införandet. Studiens slutsats är att det finns många olika typer av utmaningarsom en organisation ställs inför i förändringsarbetet när de för in RPA. Studiens resultat påidentifierade utmaningar är motstånd i organisationen, förändringsledning,processbeskrivningar, utveckling av RPA och övervakning av RPA. Det bidrag som studien tillförtill forskningsområdet är när utmaningar vid ett RPA-införande kan förekomma och hur derelaterar till varandra under RPA-införandet. / It’s common that organizations and their processes goes through a digital transformation toachieve competitive advantages. Organizations are often looking for more efficient ways ofexecuting their processes. To achieve efficiency in organizations, digital tools like RoboticProcess Automation (RPA) could be used. During the past five years RPA has become popularamong organizations due to a fast return on investments (ROI). When in a structured wayimplementing RPA in organizations, change management should be applied to handle potentialchallenges. Existing literature within the RPA field explains different types of models andholistic challenges when transitioning to RPA, however, little is known about how these changesare affecting the RPA-implementation and when they occur. Consequently, the purpose of thisstudy is to identify what challenges organizations have met during the implementation and whenthe challenges occurred. The question of the study is: What challenges in the change process isthere when implementing RPA? The study shows the importance of managing the challenges that arise initially to prevent futureissues in the RPA-project. The conclusion is that there are many different types of challenges thatan organization will encounter in change management when implementing RPA. The result of thestudy identified following challenges, organizational resistance, change management, processdescription, development of RPA and monitoring of RPA. The contribution of the study to theresearch area is when challenges during a RPA-implementation can occur and how challengesrelate to each other during the RPA-implementation.

Robotic Process Automation (RPA) är en bred variation av tillvägagångssätt och tekniska lösningar som arbetar som ett stöd för att automatisera repetitiva arbetsuppgifter. År 2017 fastslogs en ny lagstiftning i Sverige som möjliggjorde för den offentliga sektorn att automatisera beslutstöd. Detta ledde i sin tur att allt fler svenska kommuner började implementera RPA. Av Sveriges totalt 290 kommuner klassas 259 stycken som mindre kommuner. För dessa mindre kommuner är det viktigt att balansera mellan att ha tillräckligt mycket bemanning för att både klara av ekonomin samt arbetsuppgifterna. Dessutom har flera kommuner i Sverige inte råd att anställa ny personal på grund av den rådande pandemin. Flertalet av dessa mindre kommuner har ännu ej påbörjat sitt arbete med RPA. Studien undersöker sex mindre svenska kommuner som har implementerat RPA med syfte för att ta reda på de effekter och förändringar som uppstått efter implementationen. Detta har gått till genom semistrukturerade intervjuer, för att få reda på hur kommunens implementering gått till, vilka processer och inom vilka områden kommunen har valt att automatisera samt vad kommunen har sett för effekter av detta. Tematisk analys användes sedan för att hitta mönster samt teman i intervjuerna. Resultatet visade på lyckade implementeringar där kommunerna har kommit olika långt i sitt arbete och nått olika nivåer av framgång men där samtliga genom RPA har frigjort tid för sin amedarbetare. De medverkande kommunerna i studien har ett flertal nya processer att automatisera i planeringsstadiet för det kommande året. Slutsatsen av denna studie visar på att effekterna av RPA ger goda resultat genom att frigöra tid och effektivisera arbetet för de mindre kommuner som har valt att lägga ner resurser på det. I brist på andra sätt att lösa sina nuvarande problem, är RPA i dagsläget en metod för att balansera ekonomi och de växande utmaningarna för en mindre kommun. / Robotic Process Automation (RPA) is a wide variety of approaches and technical solutions that work as a support to automate repetitive tasks. In 2017, a new legislation was enacted in Sweden that made it possible for the public sector to automate decision support. This in turn led to more and more Swedish municipalities starting to implement RPA. Of Sweden's total 290 municipalities, 259 of them are classified as smaller municipalities. For these smaller municipalities, it is important to balance between having enough staff to manage both the finances and the tasks. In addition, several municipalities in Sweden cannot afford to hire new staff due to the current pandemic. Most of these smaller municipalities have not yet begun theirwork with RPA. The study examines six smaller Swedish municipalities that have implemented RPA with theaim of finding out the effects and changes that have arisen after their implementation. This has been done through semi-structured interviews to find out how their implementation went, what processes and in which areas they have chosen to automate and what they have seen for effects of this. Thematic analysis was then used to find patterns and themes in the interviews to present a common overall result with rich descriptions. This result showed successful implementations where the municipalities have come far different in their work and reached different levels of success, but where all through RPA have freed up time for their employees. These six municipalities also have a few processes to automate in the planning stage for the coming year.T he conclusion of this study shows that RPA gives good results for the smaller municipalities that have chosen to invest resources in it. In the absence of other ways to solve the current problems, RPA is a good method for balancing finance and the growing challenges for a smallermunicipality.

Thesis advisor: Krzysztof Kempa / In this work, we first examine nonlocal behavior in plasmonic systems and develop or expand upon models that enable calculation of higher-order, nonlocal responses for systems with novel geometries. The effects of nonlocality, i.e., spatial dispersion, are prominent in nanostuctures with small feature sizes, and accurate calculations of the nonlocal response of nanostructures are increasingly important for the study of novel physics at the nanoscale. Next, we consider a specific biological system, double-stranded DNA, and investigate the nonlocal and nonlinear model that describes its dynamics. We consider the regime of strong driving with THz radiation and study the parameter-space where molecular damage occurs, motivated by the prospect of using selective damage for potential novel therapies. In a related study, we also consider the possibility of generating THz radiation through the nonlinear, difference-frequency response of a plasmonic system. Plasmonic difference-frequency generation could enable deep penetration of THz signals into the body and, therefore, these projects are intimately connected. Ultimately, these two regimes of behavior, nonlocality and nonlinearity, represent rich areas for applicable research. / Thesis (PhD) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.

Dagens samhälle präglas av innovation och snabba teknologiska utvecklingar. Dessa teknologiska utvecklingar är till för att underlätta och effektivisera både vardagen och arbete för dess användare. Ett exempel på en sådan utveckling är Robotic Process Automation (RPA). RPA är robotprocesser som används i företag för att utföra enkla, repetitiva och tidskrävande arbetsuppgifter som tidigare utfördes manuellt. Tidigare forskning visar att användningen av RPA har resulterat i att redovisningsekonomens roll har förändrats. Denna förändring har inneburit olika effekter, både för- och nackdelar, för användarna av robotprocesser. Denna fallstudie på ett försäkringsbolags redovisningsavdelning syftar till att analysera hur användningen av RPA förändrar redovisningsekonomens roll, identifiera vilka effekter användningen kan få för redovisningsekonomer samt att förklara hur dessa effekter uppstår för redovisningsekonomer. För att uppnå studiens syfte användes en kvalitativ forskningsstrategi i form av semi-strukturerade intervjuer. Resultatet visar att redovisningsekonomens roll förändras till en hybridekonomroll i ett försäkringsbolag. Denna rollbeskrivning härstammar från att redovisningsekonomerna är mer aktiva, beslutsfattande och samarbetande i organisationen samtidigt som klassiska ekonomiuppgifter fortfarande är viktiga. Den förändrade rollen resulterar i två konstaterade effekter, tidseffektivitet och kvalitet på arbetet, och två icke konstaterade effekter, arbets- och kompetensförlust. För att förklara dessa effekter och hur de uppstår har även två förklarande variabler identifierats, robotprocessernas kravställning och arbetsuppgifter.