SAMMANFATTNING Postoperativ smärta uppstår genom vävnadsskador i samband med operation. Numerisk Rankningsskala (NRS) är ett smärtskattningsinstrument. Postoperativ smärta behandlas oftast med analgetika, ibland ges även någon form av opioid, till exempel Fentanyl. En annan smärtlindringsmetod som används är nervblockader där lokalbedövningsmedel bedövar nerver. Smärtlindringen ska utgå ifrån patientens unika livsvärld. En vanlig ortopedisk operation är en rekonstruktion av det främre korsbandet i knäet. Hamstringmetoden är en operationsmetod för att utföra detta ingrepp. Detta ingrepp innefattar bland annat borrningar och fixering av implantat och därför är denna operation ofta starkt associerad med postoperativ smärta. Efter en främre korsbandsrekonstruktion ställs det höga förväntningar på tidig mobilisering och snabb rehabilitering och dessa fenomen ställer högre krav på bättre postoperativ smärtlindring. Studier har gjorts för att försöka få konsensus kring den bästa metoden att lindra denna smärta, dock är inte forskarna eniga. Postoperativ smärta är ett komplext fenomen som kan bidra till lidande, det är därför viktigt att anestesisjuksköterskan har kännedom om hur denne kan på bästa sätt lindra patientens lidande och öka patientens välbefinnande. Syftet: var att jämföra smärta enligt Numerisk Rankningsskala, NRS, de två första timmarna postoperativt efter en främre korsbandsrekonstruktion med hamstringmetod; saphenusnervblockad versus en grupp där saphenusnervblockaden inte lades. Syftet var dessutom att jämföra förbrukningen av Fentanyl de två första postoperativa timmarna i vardera grupp. Metod: En kvantitativ ansats antogs och designen som användes var en prospektiv enkätundersökning. Studien hade även en kvasiexprimentell design då en jämförelsegrupp användes. En enkätundersökning med deskriptiv och analytisk statistik valdes då syftet kunde belysas och undersökas. Resultat: Det var 40 stycken patienter som medverkade i studien. Saphenusnervblockaden lades på 20 stycken patienter och det var 20 stycken patienter som ej erhöll nervblockaden. Gruppen med saphenusnervblockad rapporterade signifikant mindre smärta än gruppen utan saphenusnervblockad, NRS på 2,5 vs NRS 3,9, p< 0,003. Gruppen med saphenusnervblockad hade även en mindre postoperativ förbrukning av Fentanyl än gruppen utan saphenusnervblockad, förbrukning av Fentanyl 46,8 μg vs förbrukning av Fentanyl 101,3 μg, p< 0,003. Slutsats: En saphenusnervblockad bör vara en del av den multimodala smärtlindringen efter en främre korsbandsrekonstruktion på det deltagande sjukhuset. Denna smärtlindringsmetod leder till mindre förbrukning av Fentanyl och därmed färre biverkningar ifrån opioider. Mindre förbrukning av Fentanyl tyder även på mindre smärta hos patienterna. Färre biverkningar och mindre smärta kan i sin tur minska vårdlidande hos denna patientgrupp. Vidare forskning behövs för att denna studie ska kunna överföras på andra sjukhus. Nyckelord: främre korbandsrekonstruktion, postoperativ smärta, NRS, livsvärld, saphenusnervblockad

Pain is common among women undergoing first trimester surgical abortions. At the postoperative unit, department of gynaecology, University Hospital, Uppsala, the goal is that 80 % of the women should rate pain as £ 3 on a numeric rating scale (NRS), when leaving the unit. The aim of the study was to investigate how rating was performed at the unit and to investigate patient’s perceptions of pain after having undergone first trimester surgical abortion. 20 patients (74%) participated in the study. Ninety percent of the patients rated their pain as NRS £ 3 when leaving the unit. Seven patients (35 %) rated their pain as NRS > 3 directly after operation, and 2 (10 %) patients NRS > 3 when leaving the unit. There were no correlations between patient’s age and ratings of pain. There was no difference in rating of pain between patients with prior vaginal delivery and patients who had no prior vaginal delivery. There were no correlations between ratings of pain and gestational age. Conclusion: It is important that patients undergoing first trimester surgical abortions receive adequate pain treatment. The unit’s goal for postoperative pain treatment is achived, 90 % of the patients rated their pain as NRS £ 3 when leaving the unit.

Afin de se répliquer, les rétrovirus doivent disposer à la fois d’ARN épissés et non épissés. Chez le virus du Sarcome de Rous (RSV), l’accumulation de l’ARN non épissé dépend de l’élément NRS (Negative Regulator of Splicing). L’élément NRS est un élément bipartite. Sa région 5’ est assimilée à une séquence ESE (Exon Splicing Enhancer) à laquelle se fixent de nombreuses protéines SR tandis que sa région 3’ contient un pseudo-site 5’ non fonctionnel qui constitue un leurre qui est responsable de l’inhibition de l’épissage à l’unique site 5’ fonctionnel du virus. Seule la structure 3D de la partie 3’ du NRS qui contient le pseudo-site a été expérimentalement établie. Dans ce travail, nous avons déterminé la structure 2D de la totalité de l’élément NRS à l’aide de sondes chimiques et enzymatiques. La comparaison de cette structure expérimentale à celles que nous avons établies pour d’autres éléments NRS mutants fonctionnels et non fonctionnel ainsi qu’à celles théoriques de la totalité des virus aviaires séquencés argumente en faveur de la forte signification biologique de notre modèle. Des expériences d’épissage in vitro réalisées sur l’élément NRS sauvage ainsi que ses formes tronquées ont permis de mettre en évidence le rôle crucial de deux structures tige-boucles dans la fonction du NRS. Les expériences de purification de complexes formés avec un extrait nucléaire de cellules HeLa sur ces différents éléments NRS par des techniques chromatographie d’affinité ont permis de démontrer l’importance de l’association de ces deux structures tige-boucles avec les protéines SR et la snRNP U1. Nous avons défini un nouvel élément NRS minimal fonctionnel capable d’inhiber l’épissage et nous avons démontré l’activation de l’inhibition de l’épissage de l’élément NRS par la protéine 9G8 in vitro et in cellulo / Retroviruses require both spliced and unspliced RNAs for productive replication. Accumulation of unspliced RNA in Rous Sarcoma Virus (RSV) depends on the NRS element, (Negative Regulator of Splicing). The NRS element is bipartite. Its 5’ terminal part is considered as an ESE that binds SR proteins and its 3’ part contains a decoy 5’-splice site (ss), which inhibits splicing at the bona fide 5’ ss. Only the 3D structure of a small NRS fragment including the decoy 5’ ss had been experimentally studied. Here, by chemical and enzymatic probing of entire RSV NRS, we determine its 2D structure. By comparative analysis of 2D structures of functional and non-functional avian NRS variants and of all sequenced avian NRSs, we bring strong arguments for a biological significance of the established structure. By in vitro splicing assays, we show a crucial role of two of the established stem-loop structures and by affinity purification of complexes formed by WT and truncated NRSs in HeLa cell nuclear extract, we demonstrate their importance for SR protein and U1 snRNP association. We define a new small NRS element retaining splicing inhibitory properties and finally demonstrate the capability of the SR protein 9G8 to increase NRS activity in vitro and in cellulo

The serine/arginine-rich (SR-) family proteins constitute a diverse group of pre-mRNA splicing factors that are essential for viability. They can be characterised based on the presence of one or two RRMs and an RS domain. A subset, of which SRSF1 is the prototype, is capable of nucleocytoplasmic shuttling; a process governed by continual cyclic phosphorylation of the RS domain. In contrast, SRSF2, another member of the SR family, is unable to shuttle due to the presence of a nuclear retention sequence (NRS) at the C-terminus of its RS domain. When this NRS is fused to SRSF1, it prevents nucleocytoplasmic shuttling of the SRSF1-NRS fusion protein. In addition to its nuclear roles, SRSF1 is directly associated with the translation machinery and can activate mRNA translation of target transcripts via an mTOR-dependent mechanism. The specific mRNA translational targets that SRSF1 serves to regulate encode numerous factors including RNA processing factors and cell-cycle proteins. The aim of this work is to study the physiological relevance of SRSF1 cytoplasmic functions, as previous data have relied on overexpression systems. CRISPR/Cas9 editing was used to knock-in the NRS naturally present in SRSF2 at the SRSF1 genomic locus, creating an SRSF1-NRS fusion protein. After numerous attempts, it was only possible to obtain a single viable homozygous clone in mouse embryonic stem cells (mESCs), despite being able to successfully tag the genomic SRSF1 locus. This strongly suggests that the ablation of SRSF1 shuttling ability is highly selected against in mESCs. To assess the physiological importance of SRSF1 nucleocytoplasmic shuttling during development, a mouse model for SRSF1-NRS was also developed. SRSF1-NRS homozygous mice are born at correct Mendelian ratios, but are small in size and present with severe hydrocephalus. Finally, proteomics was used to identify interactors of endogenous cytoplasmic SRSF1 and those that bind the NRS of SRSF2 to gain insights into the mechanism of nuclear retention for non-shuttling SR proteins. In summary, this work analyses the physiological relevance of cytoplasmic SRSF1 function and the consequences of the SRSF1-NRS allele in mouse development.

Smärta är en unik upplevelse som enbart den drabbade kan bedöma. I sjuksköterskans arbetsuppgifter på en akutmottagning ingår att se till varje patients unika behov. För att inte ett vårdlidande skall skapas för patienter med smärta är det viktigt att en korrekt behandling för smärtan ges. För att detta skall kunna ske krävs att sjuksköterskan på akutmottagningen, dels har god kunskap om smärtlindring dels vet hur smärta kan utvärderas på ett adekvat sätt. Syftet är att beskriva resultat från kvantitativa studier som undersökt överensstämmelse mellan patientens subjektiva smärtskattning av akut smärta och vårdpersonalens skattning av densamma. Sammanlagt sju kvantitativa studier publicerade i vetenskapliga tidskrifter användes och dessa söktes efter i databaserna: Academic search premier, Cinahl, Medline och Science direct. Resultatet visar att visuell analog skala (VAS) eller Numerical rating scale (NRS) används för skattning av akut smärta på akutmottagningar. Vidare visar resultatet att patientens akuta smärta underskattas både av sjuksköterskor och av läkare oberoende av vilken skala som används. Underskattning av smärtan kan leda till ett vårdlidande. Det är viktigt att lyssna till patienten för att skaffa sig en korrekt bild av dennes smärtintensitet. / Program: Sjuksköterskeutbildning

Nanotechnology is a technology of the design and the applications of nanoscale materials with their fundamentally new properties and functions. Nanosensor devices based on nanomaterials provide very fast response, low-cost, long-life time, easy to use for unskilled users, and provide high-efficiency. 1-D ZnO nanostructures materials have great potential applications in various sensing applications. ZnO is a wide band gap (3.37 eV at room temperature) semiconductor materials having large exciton binding energy (60 meV) and excellent chemical stability, electrical, optical, piezoelectric and pyroelectric properties. By doping the transition metals (TM) into ZnO matrix, the properties of ZnO nanostructures can be tuned and its room  temperature ferromagnetic behavior can be enhanced, which provide the TM-doped ZnO nanostructures as promising candidate for optoelectronic, spintronics and high performance sensors based devices. The synthesis of ZnO and TM-doped ZnO nanostructures via the low temperature hydrothermal method is considered a promising technique due to low cost, environmental friendly, simple solution process, diverse 1-D ZnO nanostructures can be achieved, and large scale production on any type of substrate, and their properties can be controlled by the growth parameters. However, to synthesize 1-D ZnO and TM-doped ZnO nanostructures with controlled shape, structure and uniform size distribution on large area substrates with desirable properties, low cost and simple processes are of high interest and it is a big challenge at present. The main purpose of this dissertation aims to develop new techniques to synthesize 1-D ZnO and (Fe, Mn)-doped ZnO nanostructures via the hydrothermal method, to characterize and to enhance their functional properties for developing sensing devices such as biosensors for clinical diagnoses and environmental monitoring applications, piezoresistive sensors and UV photodetector. The first part of the dissertation deals with the hydrothermal synthesis of ZnO nanostructures with controlled shape, structure and uniform size distribution under different conditions and their structural characterization. The possible parameters affecting the growth which can alter the morphology, uniformity and properties of the ZnO nanostructures were investigated. Well-aligned ZnO nanorods have been fabricated for high sensitive piezoresistive sensor. The development of creatinine biosensor for clinical diagnoses purpose and the development of glucose biosensor for indirect determination of mercury ions for an inexpensive and unskilled users for environmental monitoring applications with highly sensitive, selective, stable, reproducible, interference resistant, and fast response time have been fabricated based on ZnO nanorods. The second part of the dissertation presents a new hydrothermal synthesis of (Fe, Mn)-doped-ZnO nanostructures under different preparation conditions, their properties characterization and the fabrication of piezoresistive sensors and UV photodetectors based devices were demonstrated. The solution preparation condition and growth parameters that influences on the morphology, structures and properties of the nanostructures were investigated. The fabrication of Mn-doped-ZnO NRs/PEDOT:PSS Schottky diodes used as high performance piezoresistive sensor and UV photodetector have been studied and Fe-doped ZnO NRs/FTO Schottky diode has also been fabricated for high performance of UV photodetector. Finally, a brief outlook into future challenges and relating new opportunities are presented in the last part of the dissertation.

Orientador: Fernanda Bono Fukushima / Resumo: Introdução: A dor aguda é um fenômeno universal. O tratamento desse evento, entretanto, ainda é visto através de diversos vieses culturais, sociais e econômicos. Em situação de dor aguda pós-operatória estima-se que 40% dos pacientes apresentam controle inadequado da dor (intensidade moderada a intensa). O presente trabalho visa analisar a percepção de pacientes recém operados quanto à analgesia pós-operatória que receberam em um hospital escola terciário de natureza pública, bem como descrever as medidas prescritas e realizadas para analgesia pós-operatória de acordo com seu registro em prontuário. Método: Estudo transversal, descritivo, realizado em pacientes internados, submetidos a procedimentos cirúrgicos cardiovasculares, gastrointestinais, ginecológicos, hemodinâmicos, mastológicos, neurológicos, ortopédicos, torácicos, urológicos ou vasculares no período de junho a dezembro de 2017 no Hospital das Clínicas da Faculdade de Medicina da UNESP, em Botucatu. Os pacientes foram entrevistados no 2º dia pós-operatório (2º PO) sobre sua experiência no 1º dia pós-operatório (1º PO) quanto ao controle da dor. Através de entrevista semiestruturada o paciente foi inquerido quanto a intensidade da sua dor, a satisfação quanto a analgesia recebida, e sua impressão geral do atendimento prestado pela equipe de saúde assistente. Foi realizada revisão dos prontuários e registrados dados quanto a frequência do registro de avaliação da dor, analgesia prescrita e fornecida, bem como sobre ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Justifications and Objectives: Acute pain is a universal phenomenon. However, the treatment of this event still has a diversity of cultural, social and economical biases. It is estimated that 40% of patients present inadequate management of pain (moderate to severe intensity) in a situation of acute postoperative pain. The aim of the present study is to analyze the perception of patients, who recently operated, regarding postoperative analgesia in a public tertiary hospital school. In addition, to describe the prescribed and performed postoperative analgesia according to registration in medical records. Methods: A cross-sectional, descriptive study was performed in hospitalized patients submitted to cardiovascular, gastrointestinal, gynecological, hemodynamic, mastological, neurological, orthopedic, thoracic, urological or vascular surgical procedures from June 2017 to December 2017 at Hospital das Clínicas, Faculdade de Medicina da UNESP, Botucatu, Brazil. Patients were interviewed on the second day of the postoperative period about their experience on the first day postoperative as to their pain control. Through a semi-structured interview, patients were asked about the intensity of pain, satisfaction as to the analgesia, and general impression of the process. Medical records were reviewed, and data were recorded as to the frequency of recorded pain, analgesia prescription and its administration, and side effects as well. Results: 159 patients met the criteria established t... (Complete abstract click electronic access below) / Mestre

Submitted by Marcelo De Paula Mendes Castilho (barcarena2004@hotmail.com) on 2018-10-24T02:50:52Z No. of bitstreams: 1 pos mestrado2 (3).pdf: 4009077 bytes, checksum: 419f6b14136acbd4404a3308130a15b8 (MD5) / Rejected by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: problema 1: Financiamento recebido No formulário de submissão consta a Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) como financiadora do seu projeto mas, no arquivo submetido, não localizei nos agradecimentos referência a esta. Caso tenha recebido o apoio favor incluí-la nos agradecimentos. Assim que tiver efetuado a correção submeta o arquivo, em PDF, novamente. Agradecemos a compreensão. on 2018-10-30T11:54:52Z (GMT) / Submitted by Marcelo De Paula Mendes Castilho (barcarena2004@hotmail.com) on 2018-11-01T18:33:31Z No. of bitstreams: 1 mestrado 4.pdf: 4010812 bytes, checksum: 8c50c5c790df0ee889ddec8b025c467e (MD5) / Approved for entry into archive by ROSANGELA APARECIDA LOBO null (rosangelalobo@btu.unesp.br) on 2018-11-06T16:03:02Z (GMT) No. of bitstreams: 1 castilho_mpm_me_bot.pdf: 4010812 bytes, checksum: 8c50c5c790df0ee889ddec8b025c467e (MD5) / Made available in DSpace on 2018-11-06T16:03:03Z (GMT). No. of bitstreams: 1 castilho_mpm_me_bot.pdf: 4010812 bytes, checksum: 8c50c5c790df0ee889ddec8b025c467e (MD5) Previous issue date: 2018-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Introdução: A dor aguda é um fenômeno universal. O tratamento desse evento, entretanto, ainda é visto através de diversos vieses culturais, sociais e econômicos. Em situação de dor aguda pós-operatória estima-se que 40% dos pacientes apresentam controle inadequado da dor (intensidade moderada a intensa). O presente trabalho visa analisar a percepção de pacientes recém operados quanto à analgesia pós-operatória que receberam em um hospital escola terciário de natureza pública, bem como descrever as medidas prescritas e realizadas para analgesia pós-operatória de acordo com seu registro em prontuário. Método: Estudo transversal, descritivo, realizado em pacientes internados, submetidos a procedimentos cirúrgicos cardiovasculares, gastrointestinais, ginecológicos, hemodinâmicos, mastológicos, neurológicos, ortopédicos, torácicos, urológicos ou vasculares no período de junho a dezembro de 2017 no Hospital das Clínicas da Faculdade de Medicina da UNESP, em Botucatu. Os pacientes foram entrevistados no 2º dia pós-operatório (2º PO) sobre sua experiência no 1º dia pós-operatório (1º PO) quanto ao controle da dor. Através de entrevista semiestruturada o paciente foi inquerido quanto a intensidade da sua dor, a satisfação quanto a analgesia recebida, e sua impressão geral do atendimento prestado pela equipe de saúde assistente. Foi realizada revisão dos prontuários e registrados dados quanto a frequência do registro de avaliação da dor, analgesia prescrita e fornecida, bem como sobre o registro de efeitos adversos. Resultados: Ao todo foram selecionados 159 pacientes, durante o período do estudo, os quais preenchiam os critérios estabelecidos para participarem da pesquisa. Contudo, 68 foram excluídos, pois no momento da entrevista já haviam recebido alta, ou não estavam no leito, ou, ainda, a cirurgia havia sido cancelada. No total foram entrevistados 91 pacientes, sendo 46 (50,5%) do sexo masculino e 45 (49,5%) do sexo feminino. A maioria dos entrevistados (86,8%) relataram presença de dor no 1º PO . Os escores médios de dor e pior dor na Escala Numérica Verbal (ENV) foram, respectivamente: 3,1/10 e 5,6/10. Todos relataram terem recebido analgesia, sendo a medicação considerada muito efetiva ou efetiva para 84,6% dos entrevistados. A grande maioria dos entrevistados se sentiram muito respeitados/muitos satisfeitos ou respeitado/satisfeitos com a analgesia recebida. Em 60,4% dos prontuários analisados, não houve qualquer registro quanto a presença ou a ausência de dor, sendo que uma escala padronizada (ENV) foi utilizada em apenas dois dos 91 pacientes. Houve registro de analgesia regular para 84,6% dos pacientes, sendo que ela consistia na maioria dos casos (51,94%) de analgésicos simples associados a opioides fracos. Aproximadamente 54% (53,84%) dos pacientes receberam analgesia sob demanda, que consistia na maioria dos casos (55,10%) de opioides fracos. Os Resumo opioides fortes foram pouco prescritos tanto no regime regular quando no de demanda (2,6% e 4,0%, respectivamente). Conclusão: Embora a grande maioria dos entrevistados tenham relatado dor no 1 oPO, e a avaliação da mesma não ter sido feita de forma sistematizada, a analgesia foi considerada muito efetiva ou efetiva para 84,6% dos entrevistados, havendo grande sentimento de satisfação e respeito pela analgesia recebida. / Justifications and Objectives: Acute pain is a universal phenomenon. However, the treatment of this event still has a diversity of cultural, social and economical biases. It is estimated that 40% of patients present inadequate management of pain (moderate to severe intensity) in a situation of acute postoperative pain. The aim of the present study is to analyze the perception of patients, who recently operated, regarding postoperative analgesia in a public tertiary hospital school. In addition, to describe the prescribed and performed postoperative analgesia according to registration in medical records. Methods: A cross-sectional, descriptive study was performed in hospitalized patients submitted to cardiovascular, gastrointestinal, gynecological, hemodynamic, mastological, neurological, orthopedic, thoracic, urological or vascular surgical procedures from June 2017 to December 2017 at Hospital das Clínicas, Faculdade de Medicina da UNESP, Botucatu, Brazil. Patients were interviewed on the second day of the postoperative period about their experience on the first day postoperative as to their pain control. Through a semi-structured interview, patients were asked about the intensity of pain, satisfaction as to the analgesia, and general impression of the process. Medical records were reviewed, and data were recorded as to the frequency of recorded pain, analgesia prescription and its administration, and side effects as well. Results: 159 patients met the criteria established to participate in the study and were selected to participate. However, 68 were excluded. The excusions were due discharge, absence at the moment of the interview or surgery postponed. A total of 91 patients were interviewed, of which 46 (50.5%) were male and 45 (49.5%) were female. Most of the interviewees (86.8%) reported some type of pain on the first postoperative period. The mean pain score and the mean worst pain score in NRS were, respectively, 3.1/10 and 5.6/10. All reported having received analgesia, and the medication was considered very effective or effective for 84.6% of the interviewees. The vast majority of the interviewees felt very respected / many satisfied or respected / satisfied with the analgesia received. In 60.4% of the charts analyzed, there was no record of presence or absence of pain. A standardized scale (NRS) was used in only two patients. There was registration of regular analgesia for 84.6% of the patients, and it consisted, in the majority of cases (51.94%), of simple analgesics associated with weak opioids. On-demand analgesia was recorded for 53.84% of patients, and it consisted, in the majority of cases (55.10%), of weak opioids only. Strong opioids were poorly prescribed in both the regular and non-demand regimens (2.6% and 4.0%, respectively). Conclusions: Although the great majority of the interviewees complained of pain in the 1st PO, and the pain evaluation was not done in a systematized way, analgesia was considered very effective or effective for 84.6% of the interviewees, with a great feeling of satisfaction and respect by the analgesia received / CAPES: 1578855

China ha llamado mucho la atención en el ámbito económico y comercial, especialmente en la era de la iniciativa de la Nueva Ruta de la Seda (NRS). Ante este mercado tan gigante, dinámico y atractivo, pero no tradicional para España, la intención de internacionalización de las pymes españolas hacia ella podría ser una temática interesante, relevante y significativa, tanto para los decisores estratégicos empresariales como para los responsables políticos, puesto que tal intención representará los intereses de las pymes en explorar y aprovechar este mercado. En el presente estudio, basándose en la teoría de la intención emprendedora y el enfoque de redes sociales, se propone un modelo integral que revela qué factores y cómo ellos determinan sistemáticamente la intención de internacionalización hacia China en el caso de las pymes españolas, bajo el contexto de la NRS. A través de un cuestionario online y la técnica de análisis multivariante (modelos de ecuaciones estructurales), 161 pymes españolas han sido estudiadas. Descubrimos que: 1) la percepción emprendedora es un firme factor antecedente para la intención emprendedora internacional de los líderes empresariales hacia China; 2) desde la perspectiva del emprendedor, su percepción emprendedora internacional depende de la red de gobierno, la red de clúster y la red interna de la empresa, pero no de la red de intermediarios y la red social básica; 3) entre las cinco redes clasificadas, el conocimiento de la NRS sólo modera la relación entre la red de gobierno y la percepción del emprendedor.

In response to the unparalleled growth of demand for air traffic during the past few decades, the Federal Aviation Administration (FAA) launched the Next Generation Air Transportation (NextGen) program to restructure the National Airspace System (NAS). Among the research is the focus on direct, wind optimal routing using geodesic routes and flight operations that do not depend solely on ground based navigation aids (NAVAID) and a fixed airspace structure. While technologies, such as the Global Positioning System (GPS), exist to locate an aircraft at higher degrees of resolution with a larger coverage, the way in which this information is conveyed is long and cumbersome. Therefore, new ways to describe the airspace is desired. The thesis presents the results of an experimental investigation into three alternatives to fix/route and GPS methods. The first method is the Navigation Reference System (NRS) using an absolute grid based strategy that has been recently implemented in limited portions of the United States airspace. The second method, the Military Grid Reference System (MGRS), is also a grid based system, and it is used by NATO, but it has not been applied to the air traffic control context. The third alternative is Point Relation Navigation (PRN), which uses a single point of reference within each Air Route Traffic Center (ARTCC) airspace and acts as a hybrid of coordinate and radial fixes. 21 airline dispatchers from a single major U.S air carrier participated in an online assessment of the five methods above through specific tasks. Results indicate that most participants prefer the fix/route system over the others, followed closely by the PRN method. However, there were varying results across all of the methods in terms of speed and accuracy of completing the tasks. This study incites further interest in strategies to describe aircraft routes operating in a more flexible airspace.