Orientador: Marcelo Carnier Dornelas / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T11:23:03Z (GMT). No. of bitstreams: 1 Goncalves_ConradodeCampos_M.pdf: 3557566 bytes, checksum: bbf1eb36c2f2344648bff12f25b9d075 (MD5) Previous issue date: 2014 / Resumo: A corona floral é uma estrutura típica das flores da família Passifloraceae. A elucidação dos mecanismos responsáveis pela formação da corona é de extrema importância para a compreensão dos processos evolutivos que permitiram a diversificação das interações com polinizadores nas espécies desta família. Este trabalho teve por objetivo identificar e caracterizar fatores de transcrição (FT) preferencialmente expressos na corona em Passiflora spp. Para tal, o banco de etiquetas de genes expressos (ESTs) PASSIOMA foi investigado e 139 cDNAs foram identificados: 69 derivados de bibliotecas florais de P. edulis, 68 de P. suberosa e 2 de P. pohlii. No intuito de atribuir identidades às sequências realizou-se uma análise de parcimônia, com a obtenção de cladogramas que permitiram a identificação de membros de 31 famílias gênicas de fatores de transcrição em Passiflora spp. Experimentos de macroarranjo mostraram que 9 genes putativos, codificadores de fatores de transcrição, apresentaram expressão nos filamentos da corona. Para a caracterização mais completa desses fatores de transcrição, foram realizados experimentos de RT-PCR em 5 destes 9 genes e hibridização in situ com dois dos 5 genes analisados por RT-PCR. Os resultados obtidos com RT-PCR indicaram que estes genes são expressos nos tecidos da corona mas também em folhas e outros órgãos florais. Os resultados da hibridização in situ confirmaram que os genes encontrados não são especificamente expressos na corona / Abstract: The corona is a floral structure typical from the Passifloraceae family. The elucidation of the mechanisms responsible for the formation of the corona is of great importance to the comprehension of the evolutionary processes that allowed the diversification of the interactions with pollinators among the species of this family. This work aimed the identification and characterization of transcription factors (FT) preferentially expressed in the corona of Passiflora spp. For that, the expressed sequence tags (ESTs) database PASSIOMA was investigated and 139 cDNAs were identified: 69 derived from P. edulis flower libraries, 68 from P. suberosa and 2 from P. pohlii. Aiming to attribute identities to the sequences, a parsimony analysis was performed, with the obtaining of cladograms that allowed the identification of members belonging to 31 different transcription factor gene families in Passiflora spp. Macroarray experiments indicated that 9 putative genes coding for transcription factors showed expression in corona filaments. Further characterization of these transcription factors included RT-PCR experiments involving 5 out of the 9 genes and in situ hybridization with 2 out of the 5 genes that were previously analyzed with RT-PCR. The RT-PCR results indicated that these genes are expressed in corona tissues, but also in leaves and other floral organs. The in situ hybridization results confirmed that the genes studied are not specifically expressed in the corona / Mestrado / Biologia Vegetal / Mestre em Biologia Vegetal

Orientador: João Sinézio de Carvalho Campos / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-27T02:43:28Z (GMT). No. of bitstreams: 1 Louzi_VitorCesardeAlmeida_M.pdf: 3130788 bytes, checksum: 990e3e0e872cccd2ed1287be8d2b6cf8 (MD5) Previous issue date: 2015 / Resumo: Fibras poliméricas sintéticas vêm sendo muito utilizadas em diversas aplicações (medicina, têxtil, etc), especialmente na forma de monofilamentos, com diversos diâmetros, devido às suas características de resistência mecânica. No entanto apresentam baixa hidrofilidade e energia livre de superfície com propriedades adesivas relativamente fracas, limitando assim suas aplicações. Com objetivo de ampliar as aplicações deste material, técnicas estão sendo desenvolvidas no sentido de melhorar estas propriedades, especialmente as de superfície. Dentre as técnicas de modificação de superfície destaca-se a descarga corona a qual pode operar em condições ambientes de temperatura e pressão, sem necessidade de agentes químicos, minimizando a geração de resíduos. Desse modo, o presente trabalho estuda os efeitos promovidos pela descarga corona em três diferentes fibras poliméricas: polipropileno (PP), politereftalato de etileno (PET) e poliamida-6 (PA-6). Amostras desses polímeros foram submetidas à descarga corona sob condições ambientes controladas. O tratamento corona foi realizado em função dos parâmetros: distância entre os eletrodos e tempo de tratamento. Após tratadas, as amostras foram submetidas às técnicas de caracterização: ângulo de contato (Método de Wilhelmy), espectroscopia no infravermelho (FT-IR/ATR), microscopia eletrônica de varredura (MEV), calorimetria exploratória diferencial (DSC), ensaios de tração e absorção de água. Os valores de ângulo de contato dinâmico foram reduzidos em até 29,6%, 27,9% e 18,6% para amostras de PP, PET e PA-6 tratadas, respectivamente. Os valores de energia de superfície aumentaram em 50,3%, 26% e 15% para PP, PET e PA-6. Amostras de PP, PET e PA-6 tratadas por descarga corona (4mm e 120s) apresentaram grau de absorção de água igual a 9,4%, 8,5% e 9,1%. A partir dos resultados obtidos com amostras de monofilamentos de PP, PET e PA-6, sem tratamento e após corona, pode-se concluir que o tratamento corona promove aumento da hidrofilidade e as propriedades térmicas e mecânicas não são afetadas. Palavras-chave: descarga corona, fibras têxteis, monofilamentos poliméricos, polipropileno, politereftalato de etileno, poliamida-6, propriedades de superfície, hidrofilidade, ângulo de contato / Abstract: Synthetic polymer fibers have been widely used in various applications, especially in the form of monofilament and under various diameters, due to its characteristics of mechanical resistance. However synthetic polymer fibers exhibit low hydrophilicity and surface free energy with relatively weak adhesive properties, thus limiting their applications. Aiming to expand the applications of these materials, techniques are being developed to improve these properties, especially the surface. Among modification techniques there is the corona discharge which can operate in ambient temperature and pressure, without the need for chemical agents, minimizing the generation residue. Thus, this research work studies the effects caused by the corona discharge in three different polymeric fibers: polypropylene (PP), polyethylene terephthalate (PET) and polyamide-6 (PA-6). Samples of these polymers were subjected to corona discharge under controlled environmental conditions. The corona treatment was performed on the basis of the parameters: distance between the electrodes and time of treatment. After treated, the samples were subjected to characterization techniques: contact angle (Wilhelmy Method), infrared spectroscopy (FT-IR/ATR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), tensile and water absorption. The dynamic contact angle values were reduced by up to 29,6%, 27,9% and 18,6% for PP, PET and PA-6 treated samples, respectively. The surface energy values increased by 50,3%, 26% and 15% for PP, PET and PA-6. PP, PET and PA-6 samples treated by corona discharge (4mm and 120s), showed the degree of water absorption equal of 9,4%, 8,5% and 9,1%. From the results obtained with samples of PP, PET and PA-6, without treatment and after treatment, can be concluded that the corona treatment enhances the hydrophilicity and the thermal and mechanical properties are not affected. Keywords: corona discharge, textile fibers, monofilament polymer, polypropylene, polyethylene terephthalate, polyamide-6, surface properties, hydrophilicity, contact angle / Mestrado / Ciencia e Tecnologia de Materiais / Mestre em Engenharia Química

Bakgrund: KOL är en progressiv inflammatorisk sjukdom som påverkar lungvävnaden och luftvägarna. Ett karakteristiskt symtom är dyspné som kan leda till rädsla för ansträngning. De flesta uppnår inte rekommendationerna för fysisk aktivitet. Under 2020 ökade trycket på hälso-och sjukvården, insatser minskade och hos riskgrupper har fysisk och psykisk ohälsa ökat. Fysioterapeuter har en viktig roll att hitta strategier för att vidmakthålla fysisk aktivitet, vilket kan försvåras under en pandemi.  Syfte: Att undersöka hur personer med kronisk obstruktiv lungsjukdom upplever sina möjligheter till fysisk aktivitet under covid-19 pandemin och hur de upplever att detta påverkar deras livskvalité. Metod: Sex semistrukturerade intervjuer hos deltagare med KOL genomfördes som analyserades genom en kvalitativ innehållsanalys.  Resultat: Dataanalysen gav tre kategorier. Resultatet visade upplevelser av minskad fysisk aktivitet, försämrat psykiskt välmående och minskat socialt stöd. Slutsats: Studien gav en möjlig förklaring till vad som påverkar möjligheterna till fysisk aktivitet under covid-19. Minskat socialt stöd och ökad oro/rädsla i relation till fysisk aktivitet påverkade vidmakthållandet av fysisk aktivitet och deltagarnas upplevda livskvalité. / Background: COPD is a progressive inflammatory disease that affects lung tissue and airways. A characteristic symptom is dyspnea that can lead to fear of effort. Most people do not meet the recommendations of physical activity. During 2020 the pressure on health careincreased, interventions reduced and amongst groups at most risk physical and mental illness has increased. Physiotherapist has an important part in finding strategies in maintaining physical activity, which can obstruct during a pandemic.  Aim: To examine how people with chronic obstructive pulmonary disease experience their opportunities to physical activity during the covid-19 pandemic and how they experience that affects their quality of life. Methods: Six semi-structured interviews with participants with COPD implemented which has been analyzed through a qualitative content analysis. Results: The analysis gave three categories. The results showed decreased levels of physical activity, deteriorating well-being and reduced social support. Conclusion: This study gave a possible explanation to what affects the opportunities to physical activity during covid-19. Reduced social support and increased anxiety/fear inrelation to physical activity was affected at the participants to maintain physical activity and experience of quality of life.

Grimaldi's commentary on death and and all its factors during the COVID-19 pandemic.

Syftet med denna uppsats är att undersöka var studenter inhämtar information om coronarestriktionerna samt deras förtroende gentemot olika medier och medieaktörer. Studien tillämpar en kvantitativ forskningsmetod med en deduktiv ansats. Populationen avser studenter vid universitet och högskola mellan 18 - 40+ år. Data har samlats in via en webbaserad enkät. Enkäten resulterade i 135 godtagbara svar som har analyserats med hjälp av Google forms. Studiens resultat visar att studenterna huvudsakligen inhämtar information om coronarestriktionerna genom journalistiska nyhetsmedier. Folkhälsomyndigheten är det mest trovärdiga källan i frågan, medan studenterna hade lägst förtroende för influencers. För ett mer trovärdigt resultat hade det krävts fler respondenter i undersökningen. Studien bidrar till teoretisk kunskap angående studenternas val av medier och medieaktörer i rapporteringen om coronarestriktionerna. Studien bidrar även till en generell uppfattning om studenternas förtroende för olika medier och medieaktörer. Vidare forskning föreslås undersöka om dessa attityder gentemot medier och medieaktörer återspeglar deras beteenden. Det hade även varit intressant att studera andra grupper samt ta hänsyn till andra variabler som kan tänkas vara bakomliggande orsaker till val av medier och medieaktörer under en samhällskris. / The aim of this essay is to investigate where students obtain information about the coronarestrictions and how they rely on different media and media actors in the matter.  The study applies a quantitative research method with a deductive approach. Data were collected through a web-based survey and was answered by 135 students aged 18 - 41+. The questionnaire consisted of a total of 17 questions regarding the students' collection of information about the coronarestrictions. Collection of information regarding the coronarestrictions takes place mainly through journalistic news media. The public health authority information about the coronarestrictions proved to be the most credible source among the students. The results also showed that influencers were the least reliable. The conclusion of the study is not completely credible. The study required more extensive answers.  This contributes to a lack of factors which leads to the result of the study not being enough. The study contributes to theoretical knowledge about students' collection of information in the media about the coronarestrictions. The choice of media actors and attitudes towards them. Further research is suggested to investigate whether these attitudes towards the media and media actors reflect their behavior. It would also have been interesting to study other groups and take into account other variables that may be underlying reasons for the choice of media and media actors during a societal crisis.

Fastighetstillgångar har historiskt sett varit mer defensiva än aktiemarknaden som helhet. Flera tidigare studier pekar på motsatsen: att svenska fastighetsaktier presterar sämre under börsnedgångar och inte är mer defensiva än resten av aktiemarknaden. Den senaste corona-pandemin har i likhet med finanskrisen 2007-8 orsakat stora börsnedgångar. Föreligger det någon skillnad mellan kriserna i form av risk, avkastning och korrelation för fastighetsaktier i förhållande till resten av den svenska aktiemarknaden (OMXS 30)? Resultatet av studien visar att det finns både skillnader och likheter mellan de två börsfallen. Samtliga fastighetsaktier under både finanskrisen 2007-8 och corona-pandemin har presterat sämre än Stockholmsbörsen (OMXS 30) generellt. Nedgången 2020 under corona-pandemin har för fastighetsaktier varit betydligt större än under finanskrisen 2007-8 i jämförelse med OMXS 30. Skillnader i beta-tal har även identifieras. Det genomsnittliga beta-talet under finanskrisen var 0,97 medan det under corona-pandemin var 1,74 för de analyserade fastighetsaktierna. En ökning på 79 procent mellan kriserna. Även fast det handlar om två helt olika typer av kriser tenderar fastighetsaktier att bli mer volatila i förhållande till resten av aktiemarknaden trots dess defensiva karaktär. / Historically, Real Estate Assets have been more defensive than the stock market as a whole. Several previous studies indicate that Swedish Real Estate Stocks perform worse during stock market declines and do not act more defensive than the rest of the stock market. The latest corona-pandemic has caused major stock market declines similar to the financial crisis of 2007-8. Is there any difference between the crises in terms of risk, return and correlation for Real Estate Stocks in relation to the rest of the Swedish stock market (OMXS 30)? The results of the study show that there are both differences and similarities between the two stock market declines. All Real Estate Stocks during both the 2007-8 financial crisis and the corona-pandemic have performed worse than the Swedish stock market (OMXS 30) in general. The fall in 2020 during the corona-pandemic has been significantly greater for Real Estate Stocks than during the financial crisis 2007-8 in comparison with the OMXS 30. Differences in beta have also been found. The average beta during the financial crisis 2007-8 was 0.97 and 1.74 during the corona pandemic (Covid-19). An increase of 79 percent between the two crises. Although these are two completely different types of crises, Real Estate Stocks tend to be more volatile compared to the rest of the stock market. Despite its defensive nature over time.

HINTERGRUND: Neben direkten gesundheitlichen Folgen nach einer COVID-19-Erkrankung zeigten sich bereits im Verlauf der Coronapandemie zunehmend auch indirekte Auswirkungen der Krise auf die deutsche Bevölkerung. Diese äußerten sich einerseits in Form von generellen, gesundheitsbezogenen und pandemiespezifischen Ängsten, sowie psychischen Belastungen. Andererseits entwickelte sich in Teilen der Bevölkerung eine Corona-Skepsis als Reaktion auf die politischen Maßnahmen zur Infektionsprävention. Ein diesbezüglicher Zusammenhang pandemiebedingter psychischer Veränderungen zur Gesundheit wurde bislang noch nicht ausreichend untersucht. FRAGESTELLUNG: Mit dieser Arbeit sollen psychische Belastungen, Ängste und Skepsis im Rahmen der COVID-19-Pandemie erfasst und entsprechende Einflussfaktoren identifiziert werden. Weiterhin wird ein diesbezüglicher Zusammenhang zu gesundheitlichen Beschwerden analysiert. METHODEN: Basierend auf Daten der 32. Erhebungswelle der Sächsischen Längsschnittstudie (N = 321; Erhebungsintervall März bis Juli 2021) wurden u.a. deskriptive Analysen und Mittelwertvergleiche durchgeführt, sowie die Ergebnisse präpandemischen Daten und aktuellen Vergleichsstudien gegenübergestellt. Als Messinstrumente dienten dabei eine neu konstruierte Corona-Angst-Skala, ein Item zur Corona-Skepsis, soziodemographische Faktoren und die Befindensvariablen D-Score, L-1, SOP-2, OSSS-3, RS-5, PHQ-4, SWE, FLZ-M, SOC-9, BFI-10, LS-S, G-Score, GBB-8, sowie weitere Einzelitems. ERGEBNISSE: Bezüglich des Auftretens psychischer Belastungen (D-Score, Suizid-Item, L-1) ließen sich in Hinblick auf Vorjahreswerte keine Veränderungen während der Pandemie feststellen. Zur Evaluierung der Corona-Angst wurde ein eigener Fragebogen entwickelt und anschließend auf dessen Basis ein Score mit sieben Items konstruiert. Reliabilität (α = .814) und Validität (r = .211) der neuen Corona-Angst-Skala konnten bestätigt werden. Der Mittelwert der Angst lag bei 17,06 (SD = 5,38; WB: 7-35 Punkte), was im Vergleich zu anderen Studien als moderat bewertet werden konnte. Signifikante Korrelationen der Corona-Angst zu Variablen des psychischen Befindens ließen sich bezüglich SOP (p = .017), OSSS-3 (p = .002), PHQ-4 (p = .039) und D-Score (p = .007) belegen. Entsprechende soziodemographische Zusammenhänge konnten in dieser Analyse nicht bestätigt werden. Die Corona-Skepsis wurde anhand eines Einzelitems untersucht und betrug durchschnittlich 2,53 (SD = 1,31; WB: 1-5 Punkte). Insgesamt wiesen 25,6 % der Stichprobe entsprechende Tendenzen auf. Bezüglich der Befindensvariablen ergab sich kein Zusammenhang zur Corona-Skepsis. Signifikante Korrelationen zu Bildungsabschluss (χ2 = 11,260; p = .001) und Wohnort (χ2 = 7,977; p = .004) belegen einen Bezug zu soziodemographischen Einflussfaktoren. Im Studienvergleich ergab sich eine große Heterogenität der Menschen mit coronaskeptischen Einstellungen, welche insbesondere das Bildungsniveau betraf. Eine Zunahme gesundheitlicher Beschwerden während der Pandemie konnte in dieser Studie nicht nachgewiesen werden. Dennoch ließen sich diesbezüglich Korrelationen zur Corona-Angst anhand des G-Score (Gesamt; p = .024), der G-Score-Items Schlaflosigkeit (p = .016) und Nervosität (p = .007), sowie Items zum Gesundheitszustand (p = .001), belegen. Des Weiteren wurde ein Zusammenhang des GBB-8 zur Corona-Skepsis ermittelt (p = .012). SCHLUSSFOLGERUNGEN: Insgesamt ließen sich anhand der Ergebnisse sowohl eine vorhandene Corona-Skepsis in der Bevölkerung als auch moderate Veränderungen des psychischen und physischen Gesundheitszustands während der Coronapandemie belegen. Diesbezüglich konnten zudem einige Einflussfaktoren identifiziert werden. Die Ergebnisse stimmen damit größtenteils mit der aktuellen nationalen und internationalen Studienlage überein. Da bisherige Analysen jedoch hauptsächlich auf Daten aus Erhebungszeiträumen in 2020/21 basieren, kann perspektivisch eine Zunahme psychischer Belastungen und körperlicher Manifestationen in der Bevölkerung nicht ausgeschlossen werden. Um derartigen Entwicklungen möglichst frühzeitig entgegenwirken zu können, erfordert es regelmäßige Kontrollerhebungen in kurzen Intervallen, sowie in Hinblick auf zukünftige Pandemien bereits jetzt einen Ausbau psychotherapeutischer und sozialer Unterstützungsangebote, insbesondere für besonders belastete Bevölkerungsgruppen (z.B. Kinder und Jugendliche).:Abbildungsverzeichnis III Tabellenverzeichnis V Abkürzungsverzeichnis VI 1. EINLEITUNG 1 2. THEORETISCHER HINTERGRUND 2 2.1. COVID-19 – Erreger, Symptome, Therapie und Prävention 2 2.2. Erkrankungsrisiko der Bevölkerung und Einflussfaktoren 3 2.3. Risiko von COVID-19 im Verhältnis zur Influenzaerkrankung 4 2.4. Verlauf, Maßnahmen und Folgen der Coronapandemie in Deutschland 6 2.5. Rückblick: Historische Pandemien und deren Folgen für Psyche und Gesellschaft 10 2.6. Allgemeine Zusammenhänge zwischen Angst und Gesundheitszustand 11 3. AKTUELLE STUDIENLAGE 13 3.1. Psychische Belastungen im Verlauf der Coronapandemie 13 3.2. Scores zur Quantifizierung coronaspezifischer Ängste 15 3.3. Einflussfaktoren der Corona-Angst 16 3.4. Entwicklung und Einflussfaktoren der Corona-Skepsis 18 3.5. Einschätzung der körperlichen Gesundheit während der Coronapandemie 21 3.6. Limitationen bisheriger Studien 23 4. ZIEL UND FRAGESTELLUNGEN 24 5. METHODEN 26 5.1. Fakten zur Studie 26 5.2. Instrumente des Fragebogens 27 5.3. Statistische Analyse 34 6. ERGEBNISSE 36 6.1. Datenerhebung und soziodemographische Analyse 36 6.2. Psychische Belastung vor und während der COVID-19-Pandemie im Vergleich 38 6.3. Auswertung des Corona-Fragebogens 39 6.4. Validierung und Ergebnisse der Corona-Angst-Skala 42 6.5. Validierung und Ergebnisse des Corona-Skepsis-Items 46 6.6. Befindensvariablen und Corona-Angst-Score 47 6.7. Befindensvariablen und Corona-Skepsis 48 6.8. Soziodemographie und Corona-Angst-Score 50 6.9. Soziodemographie und Corona-Skepsis 52 6.10. Gesundheitliche Beschwerden während der COVID-19-Pandemie 54 7. DISKUSSION 59 7.1. Limitationen dieser Studie 80 7.2. Ausblick 81 8. ZUSAMMENFASSUNG 83 9. SUMMARY 85 Literaturverzeichnis VII

É apresentado neste trabalho um novo método de carga de filmes dielétricos com descarga corona, no qual a corrente de carga da amostra é mantida constante durante a deposição dos íons, enquanto o potencial de superfície é medido pela técnica do capacitor vibrante. O método foi aplicado no estudo de transporte e armazenamento de portadores em polímeros, principalmente no Teflon FEP e PVDF. No Teflon FEP carregado com corona positiva e negativa, a superfície do material exerce um papel predominante. O transporte de elétrons é dominado pelos traps de volume. Para a corona positiva a injeção é controlada pelo trapping e detrapping das armadilhas superficiais. No PVDF os resultados obtidos são razoavelmente independentes da polaridade da descarga corona. Para baixos campos elétricos o potencial de superfície parece ser determinado pela condutividade do material, perturbado pela existência de uma polarização de volume. / A new method of charging dielectric films with corona current is presented here, the sample charging current being keept constant during the deposition, while the surface potential is measured by vibrating capacitor technique. The method was applied to study the carrier transport and storage in polymers, mainly in Teflon FEP and PVDF. For positive and negative corona in Teflon FEP, the surface plays an important role. The electron transport is dominated by bulk traps. For positive corona injection into the volume is controlled by surface trapping and detrapping. For PVDF the results are almost independent of the current polarity. For low electrical fields, the results indicate that the surface potential is determined by the material conductivity, perturbed by the build up of a bulk polarization.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-16T10:48:35Z No. of bitstreams: 2 Dissertação - Juliana Paula Félix - 2018.pdf: 1739140 bytes, checksum: 14e7528cefac5d3322e49131936f3c86 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-16T10:49:04Z (GMT) No. of bitstreams: 2 Dissertação - Juliana Paula Félix - 2018.pdf: 1739140 bytes, checksum: 14e7528cefac5d3322e49131936f3c86 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-16T10:49:04Z (GMT). No. of bitstreams: 2 Dissertação - Juliana Paula Félix - 2018.pdf: 1739140 bytes, checksum: 14e7528cefac5d3322e49131936f3c86 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work, we investigate the problem of finding identifying codes of minimum size in a variety of graph classes, such as trees corona products, Cartesian products and complementary prisms. For caterpillar trees, we show the minimum size of an identifying code on complete caterpillars, brooms and double brooms. We also prove a sharp upper bound for the general case. For coronas $K_n \circ \overline{K}_m$, we prove what is the minimum size of an identifying code. We demonstrate a sharp upper bound for an identifying code of the Cartesian product of a star and a path $K_{1,n} \square P_m$ and, when $n=3$, we conjecture that the limit proposed is minimum. We also find the minimum cardinality of an identifying code in the complementary prism of complete bipartite graphs and complete split graphs, among with other results: we demonstrate that the complementary prism graph $G\overline{G}$ is identifiable if, and only if, $G$ has at least two vertices; we find what is the smallest size possible of an identifying code of complementary prisms; we prove a sharp upper bound for an identifying code of the complementary prism $G\overline{G}$ of a connected graph $G$, showing that the set $C = V(G)$ is an identifying code with the size proposed and, finally, we determine the size of a minimum identifying code of the complementary prism of a complete bipartite graph, showing that it is an example of a graph that attains our upper bound. / Neste trabalho, investigamos o problema de se encontrar códigos identificadores de cardinalidade mínima em diversas classes de grafos, tais como árvores, produtos coronas, produtos Cartesianos e prismas complementares. Para árvores caterpillar, determinamos a cardinalidade mínima de um código identificador em caterpillars completo, grafos broom e broom duplo, e provamos um limite superior justo para caterpillars gerais. Para coronas, determinamos a cardinalidade mínima de um código identificador em $K_n \circ \overline{K}_m$. Para produtos Cartesianos, investigamos códigos identificadores em grafos $K_{1,n} \square P_m$, definimos um limite superior justo para o caso em que $n=3$ e um limite superior mais abrangente para o caso em que $n \geq 3$. Quando $n=3$, conjecturamos que o limite proposto é mínimo. Para prismas complementares de grafos, encontramos o tamanho de um código identificador mínimo em grafos bipartidos completos e grafos split completos. Para prismas complementares, obtivemos ainda outros resultados: demonstramos que um grafo prisma complementar $G\overline{G}$ é identificável se, e somente se, a ordem de $G$ é pelo menos dois; definimos o menor tamanho possível de um código identificador em um grafo $G\overline{G}$; determinamos um limite superior justo para o código identificador de um grafo conexo, mostrando também que seu conjunto de vértices é um conjunto identificador com o tamanho proposto e, finalmente, mostramos que o grafo bipartido completo é um exemplo de grafo que atinge a igualdade do limite superior apresentado.

The degradation of high voltage electrical insulation is a prime factor that can significantly influence the reliability performance and the costs of maintaining high voltage electricity networks. Little information is known about the system of localized degradation from corona discharges on the relatively new silicone rubber sheathed composite insulators that are now being widely used in high voltage applications. This current work focuses on the fundamental principles of electrical corona discharge phenomena to provide further insights to where damaging surface discharges may localize and examines how these discharges may degrade the silicone rubber material. Although water drop corona has been identified by many authors as a major cause of deterioration of silicone rubber high voltage insulation until now no thorough studies have been made of this phenomenon. Results from systematic measurements taken using modern digital instrumentation to simultaneously record the discharge current pulses and visible images associated with corona discharges from between metal electrodes, metal electrodes and water drops, and between waters drops on the surface of silicone rubber insulation, using a range of 50 Hz voltages are inter compared. Visual images of wet electrodes show how water drops can play a part in encouraging flashover, and the first reproducible visual images of water drop corona at the triple junction of water air and silicone rubber insulation are presented. A study of the atomic emission spectra of the corona produced by the discharge from its onset up to and including spark-over, using a high resolution digital spectrometer with a fiber optic probe, provides further understanding of the roles of the active species of atoms and molecules produced by the discharge that may be responsible for not only for chemical changes of insulator surfaces, but may also contribute to the degradation of the metal fittings that support the high voltage insulators. Examples of real insulators and further work specific to the electrical power industry are discussed. A new design concept to prevent/reduce the damaging effects of water drop corona is also presented.