Desenvolvimento e avaliação de tecnologia para soldagem TIG com pulsação ultrassônica

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Mecânica, Florianópolis, 2013.O processo de soldagem TIG é caracterizado pela sua excelente estabilidade do arco, o que confere soldas com elevado grau de qualidade. Esta característica faz deste processo a escolha ideal para aquelas aplicações cujo propósito é a realização de soldas de compromisso. Entretanto, sua relativa baixa capacidade de produção o torna muitas vezes insatisfatório nas aplicações industriais. Neste contexto, diversos métodos vêm sendo constantemente desenvolvidos com o objetivo de elevar os níveis de produtividade conseguidos associado à qualidade da junta soldada. Com o avanço na tecnologia dos transistores de potência, uma nova possibilidade tem sido alvo recentemente de estudos (os primeiros trabalhos publicados datam de 1999) que consiste na excitação ultrassônica do arco mediante a pulsação da corrente em frequências acima de 20 kHz. Os estudos mostram melhorias quanto à produtividade, à penetração da solda e às características metalúrgicas e propriedades mecânicas das soldas, dentre outras. Diante do potencial que se vislumbra a partir dos resultados desses estudos, foi projetada e, construída, uma fonte de soldagem dotada de características especiais capaz de realizar a pulsação da corrente com diversos formatos de onda (a saber, senoidal, retangular e triangular), em frequências que podem ser variadas entre 20 e 80 kHz. Também foi desenvolvido um sistema capaz de medir com elevada repetitividade a pressão do arco nos processos com eletrodos não consumíveis. Com a bancada assim constituída, foram realizados ensaios que permitiram determinar as seguintes alterações quando do uso da pulsação da corrente em frequências ultrassônicas: aumento substancial da pressão do arco, cujo valor depende da frequência utilizada; aumento da estabilidade do arco, ao ponto de permitir a manutenção do arco com baixíssimos valores de corrente; aumento do rendimento de fusão, mas sem uma variação significativa da relação entre a penetração e a largura do cordão; um aumento da dureza do metal de solda, que parece estar associado ao aumento da taxa de resfriamento e este, por sua vez, associado a um aumento da condução térmica; transição mais suave entre a dureza do metal de solda e zona afetada pelo calor, que tem benefícios potenciais quanto ao desempenho da junta soldada. 2013-12-05T22:34:15

Correlações das classes pedológicas com características geotécnicas aplicadas ao uso e ocupação do solo

A avaliação do comportamento hidromecânico dos solos é de suma importância para o uso e ocupação dos solos em suas múltiplas aplicações. Os levantamentos pedológicos permitem indicar a ocorrência do lençol d’água, o grau de saturação, a atividade do solo, a presença de minerais expansivos, as características de drenagem, erodibilidade e de plasticidade, a ocorrência de solos porosos, permeáveis e impermeáveis, além de trazer informações acerca dos solos de jazidas que sejam de interesse em projetos geotécnicos. O estudo objetiva indicar o uso de solos para construção de barragens no município de São Bento do Una, Pernambuco, Brasil, utilizando um ambiente de Sistema de Informações Geográficas (SIG), considerando as características dos solos com base na Geotecnia com as propriedades dos solos das Classes Pedológicas. São apresentados mapas com indicação de áreas de susceptibilidades de solos problemáticos quanto ao colapso, a expansão, a erosão, a dispersão, de ser mole e indicação de áreas com materiais de empréstimo (jazidas) para construção dos elementos de barragens. Os mapeamentos auxiliam na localização de áreas com potencial de jazidas de materiais para o uso em aplicações na engenharia, e permite identificar a susceptibilidade dos solos Problemáticos para uso na Engenharia Civil. Estas verificações possibilitam eficiência e economia de materiais, assim como segurança da obra

Analysis of Systemic and Cutaneous Inflammatory Immune Response in Canine Atopic Dermatitis

Background: Canine atopic dermatitis (CAD) is a chronic and inflammatory disease present in veterinary dermatological practice. The inflammation in CAD is triggered by environmental allergens and skin microorganisms, which are responsible for the worsening of cutaneous lesions. This continuous activation of skin inflammatory process can induce the production of free radicals that also contribute to cellular damage and ultimately leads to changes in blood parameters in dogs with CAD. Although there are reports of inflammatory parameters in CAD, there are a lack of studies correlating skin lesions, blood leukocytes and oxidative stress. Based on that,this study aimed to evaluate the integumentary and systemic inflammatory response in dogs with atopic dermatitis. Materials, Methods & Results: Dogs with confirmed diagnosis of canine atopic dermatitis (n = 10) were divided in two groups according to CADESI-IV: AI, with CADESI between 0-10, AII, with CADESI between 10-34, and control group (n = 5). Blood-biochemical and histological analysis were performed to access systemic and cutaneous inflammatory response. AII group tended to higher neutrophil and eosinophil counts, as well as neutrophil/lymphocyte ratio (NLR) when compared to AI. The albumin was lower in AII compared to AI and control (P < 0.05), while total bilirubin and malondialdehyde (MDA) did not differ between groups. NLR (r = 0.64 and P = 0.04) and MDA (r = 0.54 and P = 0.1) were positively correlated with CADESI, while albumin was negatively correlated with CADESI (r = -0.79 and P = 0.005). Histopathological analysis revealed a larger number of neutrophils, macrophages and mast cells in AI and AII than in control group (P < 0.05). Discussion: In this study it was possible to evaluate the systemic and cutaneous leukocyte dynamics in CAD. Skin inflammation induces the production of chemotactic molecules contribute to neutrophil outflow from blood vessel toward the affected tissue, which can be visualized as perivascular inflammatory infiltrate and exocytosis. At systemic level, there was a tendency to increase in total leukocytes and circulating neutrophil count in group AII, as well as in neutrophil/lymphocyte ratio (NLR), when compared to AI. The NLR is a widely available and inexpensive laboratory biomarker that quantifies systemic inflammation, being used in human medicine to evaluate prognosis in different types of cancer. In our study, dogs in AII group showed an increased NLR compared to AI and control, which demonstrates the influence of skin injury in systemic parameters. Furthermore, AII group is composed of dogs with greater lesion state, which reflects in higher NLR values. Since this disease is known by its chronicity and may remain stable for years, NLR may be a novel biomarker to evaluate acute exacerbation in CAD and could potentially explain why some patients have longer crisis duration and frequent flares. The maintenance of the inflammatory state also induces the production of oxidizing substances, which possibly exceed the total antioxidant capacity, generating a situation of oxidative stress, which can result in damage to membrane lipids and release of their products. MDA is reliable and is the most commonly used marker of the overall lipid peroxidation level and the presence of oxidative stress. This result may be related with the antioxidant system, such as albumin and bilirubin, which was able to promote an efficient control of oxidant substances. In conclusion, the presented data demonstrated an inflammatory process progression as well as introduced NLR as a potential marker of disease exacerbation in CAD

Electron-Transfer-Induced Side-Chain Cleavage in Tryptophan Facilitated through Potassium-Induced Transition-State Stabilization in the Gas Phase

Fragmentation of transient negative ions of tryptophan molecules formed through electron transfer in collisions with potassium atoms is presented for the first time in the laboratory collision energy range of 20 up to 100 eV. In the unimolecular decomposition process, the dominating side-chain fragmentation channel is assigned to the dehydrogenated indoline anion, in contrast to dissociative electron attachment of free low-energy electrons to tryptophan. The role of the collision complex formed by the potassium cation and tryptophan negative ion in the electron transfer process is significant for the mechanisms that operate at lower collision energies. At those collision times, on the order of a few tens of fs, the collision complex may not only influence the lifetime of the anion but also stabilize specific transition states and thus alter the fragmentation patterns considerably. DFT calculations, at the BHandHLYP/6-311++G(3df,2pd) level of theory, are used to explore potential reaction pathways and the evolvement of the charge distribution along those.F.F.d.S., T.C., and A.R. acknowledge the Portuguese National Funding Agency FCT-MCTES for IF-FCT IF/00380/2014, SFRH/BD/52538/2014, and PD/BD/114449/2016 and together with P.L.-V. the research grants PTDC/FIS-AQM/31215/2017 and PTDC/FIS-AQM/31281/2017. This work was also supported by Radiation Biology and Biophysics Doctoral Training Programme (RaBBiT, PD/00193/2012); UIDB/00068/2020 (CEFITEC) and UIDB/04378/2020 (UCIBIO). M.J.C. and A.G. also thank FCT-MCTES UIDB/04046/2020 and UIDP/04046/2020, and A.G. thanks the SFRH/BPD/89722/2012 grant. G.G. is partially funded by the Spanish Ministerio de Ciencia, Innovacion y Universidades (project no. PID2019-104727RB-C21) and CSIC (Project LINKA20085). O.I. acknowledges the Icelandic Center of Research (RANNIS) and the University of Iceland Research Fund for financial support. The authors thank Ragnar Bjornsson for fruitful discussions while preparing this manuscript.Pre-prin

CD45+, CD68+ and E-cadherin+ Expressions in Skin Dogs Naturally Infected by Leishmania infantum

Background: In canine leishmaniasis (CanL), infection occurs through phlebotomine vectors that inoculate the protozoan Leishmania infantum into the skin that infected macrophages and activated dendritic cells (CD). Dogs with CanL present variable clinical manifestations, being common the presence of cutaneous lesions. The aim of this study was to evaluate the expression of CD45+, CD68+ and E-cadherin+  associating the skin sentinels cells and to compare the clinical-dermatological manifestations in the skin of dogs naturally infected by L. infantum.Materials, Methods & Results: Dogs infected (n = 22) by L. infantum were divided into asymptomatic group (AD, n = 9), and symptomatic group (SD, n = 13), according criteria based on the presence or absence of skin changes. Dogs non-infected (CD, n = 5) were included as control group. Samples of skin biopsies collected from scapular region were processed by routine histology and labeled by immunohistochemistry with monoclonal antibodies against CD45+, CD68+ and E-cadherin+, and were described as none, mild, moderate and intense. SD presented keratoconjunctivitis, onychogryphose, lichenification, depigmentation, alopecia, hypotrichosis, erythematous dermatitis, exfoliative dermatitis, ulcerative dermatitis and crusted dermatitis, and the frequency these alterations was expressed as percentage. The results of hematological and biochemical parameters were analyzed by Kruskal-Wallis test followed by the Dunn’s test and expressed as mean ± standard deviation, with values P < 0.05. Leukocytosis (not significant), red blood cells, hematocrit and hemoglobin (P < 0.05), total protein serum (P < 0.05), globulins (P < 0.05), albumin and A/G ratio (P < 0.01) were altered in SD in relation to CD. Cutaneous cellular infiltration, composed by macrophages, plasma cells, lymphocytes and neutrophils, was observed in CD. There was an increase of expression of the markers in SD when compared to the other groups, as moderate CD68+ expression and L. infantum, and intense CD45+ and E-cadherin+ expressions.Discussion: Cutaneous involvement is very important in CanL, as it corresponds to where is the first interaction between the parasite and the immune system. Dermatological clinical signs, leukocytosis, anemia, globulins levels have been reported for dogs naturally infected by L. infantum. Inflammatory infiltrate was distributed at superficial and deep dermis, which was composed by mononuclear cells as macrophages, plasma cells, lymphocytes and neutrophils. To characterize the immune sentinels cells in the skin it was evaluated CD45+, CD68+ and E-cadherin+ expressions. In syntomatic dogs, our results revelead an increase of expression of these markers. CD45+ is one of the most abundant molecules expressed on the white blood cell surface in various mammals, while CD68+ is a myelomonocytic marker that seems to be retained during monocyte differentiation. In the skin, increased numbers of CD68+ are related to dendritic epidermal cells, which can be expressed as CD45+/CD1a-/HLA-DR+. DCs of the skin, particularly epidermal Langerhans cells (LCs), form networks anchored to neighboring keratinocytes via E-cadherin. Thus, CD45+, CD68+ and E-cadherin+ expressions may be related to activation of skin sentinels cells in dogs naturally infected by L. infantum. Our results indicated that CanL modify the CD45+, CD68+ and E-cadherin+ expressions, which characterize the immune sentinels cells activation that promove the recruitment the cellular infiltrate, which was composed by macrophages, plasma cells, lymphocytes and neutrophils. Thus, these informations may contribute to the follow-up of CanL progression in skin

TERAPIA OTOLÓGICA INDUZ IMUNOTOXICIDADE EM CÃO

Pharmacodermia can be defined as adverse reactions in skin, mucous membranes and appendages, sometimes having immunomediated character. The diagnosis is based on the patient clinical-laboratorial evaluation, involving a research about factors related to the drug use and its adverse effects. In veterinary medicine, reports of pharmacodermic reactions are scarce. Therefore, the aim of the present study is to report an adverse reaction after otologic therapy in dogs. A 2-year-old female canine patient with a history of bilateral auricular pruritus with a three-week course was attended. At the time, auricular cytology was performed, evidencing the presence of high numbers of yeast cells and cocci, as well as desquamative cells. It was then opted for otologic solution composed of Gentamicin, Clotrimazole, Betamethasone and Benzocaine. The clinical presentation progressed satisfactorily until the tenth day of treatment, when the patient presented intense erythema and meliceric secretion. Cytological examination was repeated, as well as culture of aerobic bacteria. A piogranulomatous inflammatory infiltrate with low bacterial and fungal content was evidenced in these examinations, corroborating with the findings of the bacterial culture. Faced with the suspicion of pharmacodermia, all therapeutic compounds were exchanged, and the patient progressed satisfactorily until the end of the treatment. Because it is still a composed otological solution, the cause of the reaction can not be attributed to specifically one of the compounds. However, there is a need to raise the awareness of the veterinarian about the identification and appropriate intervention in adverse drug reactions, as well as his scientific contribution to the dissemination of this information.As farmacodermias podem ser definidas como reações adversas em pele, mucosas e anexos, tendo, por vezes, caráter imunomediado. O diagnóstico baseia-se na avaliação clínico-laboratorial do paciente, envolvendo uma pesquisa acerca de fatores relacionados ao uso do fármaco e seus efeitos adversos. Na medicina veterinária, são escassos os relatos de reações farmacodérmicas. Logo, o objetivo do presente trabalho é relatar uma reação adversa após terapia otológica em cão. Foi atendido um paciente canino, fêmea, 02 anos de idade, com histórico de prurido auricular bilateral com evolução de três semanas. Na ocasião, foi realizado exame citológico auricular, evidenciando presença de elevada quantidade de células leveduriformes e cocos, além de células descamativas. Optou-se, então, por terapia à base de solução otológica composta por Gentamicina, Clotrimazol, Betametasona e Benzocaína. O quadro clínico evoluiu de forma satisfatória até o décimo dia de tratamento, quando a paciente apresentou intenso eritema e secreção melicérica bilateralmente. Repetiu-se o exame citológico, assim como realizou-se cultura de bactérias aeróbicas, sendo evidenciado em tais exames um infiltrado inflamatório piogranulomatoso, com pouca presença de conteúdo bacteriano e fúngico, corroborando com os achados da cultura bacteriana. Diante da suspeita de farmacodermia, procedeu-se com a troca de todos os compostos terapêuticos, tendo a paciente evoluído de forma satisfatória até o término do tratamento. Por tratar-se ainda de uma solução otológica composta, não se pode atribuir a causa da reação a especificamente um dos compostos. Contudo, reforça-se a necessidade de conscientização do médico veterinário acerca da identificação e adequada intervenção nas reações adversas medicamentosas, assim como espera-se sua contribuição científica na difusão dessas informações

Influenza seroprotection correlates with predominant circulating viruses during 2014/15 and 2015/16 seasons in Portugal

Rede Portuguesa de Laboratórios para o Diagnóstico da GripeBACKGROUND: Population immune profile for influenza is highly affected by circulating influenza viruses, thus changing the risk of infection for influenza. This study aims to assess influenza immunity in the Portuguese population by age groups, during 2014 and 2015 and establish a relationship between seroprotection and circulating influenza viruses in 2014/15 and 2015/16 seasons. METHODS: Two cross-sectional studies were developed based on a convenience serum sample collected in June 2014 (n=626) and July 2015 (n=675) in hospitals from mainland and Azores and Madeira.Serums equally represent all age groups. Antibody titers were evaluated by HI assay for strains recommended for seasonal influenza vaccine northern hemisphere,2014/15 and 2015/2016. Seroprevalences were estimated for each strain by age group and the association with seasonal cumulative influenza-like illness (ILI) rates for influenza virus during both seasons was analised. RESULTS: In June 2014 the highest seroprotection was observed for influenza A(H3) (39.0%; 95% CI: 36.2-43.8%) and A(H1)pdm09 (29.7; 95% CI: 26.3-33.4%), with higher levels in children 5-14 years old. In 2014/2015 a dominant circulation of influenza B/Yamagata was observed with high incidence rates in individuals under 65 years old, the ones that had lower seroprotection. Although before the start of the season high protection for A(H3) was observed, the circulation of the new drift A(H3) strains had gained an immunological advantage,in accordance with A(H3) elevated incidence rates observed during 2014/15. In July 2015 the highest seroprotection was observed for influenza B/ Yamagata (55.1%; 95% CI: 51.4-58.9%), 2.4 times the estimated 2014.This increase was even more pronounced in younger (≤ 4 years old), 6.3 times increase in 2015.This fact is in agreement with the predominant influenza B virus detected and the high ILI incidence rate observed in children during 2014/2015 epidemic. Seroprotection levels for influenza A in July 2015 were not significantly different from 2014.During 2015/16 season, influenza A(H1N1)pdm09 was predominant, with high incidence rate in < 65 year old. Influenza B/Victoria lineage,although detected at low levels increased in frequency, in agreement with the lowest level of seroprotection detected in the general population before the start of 2015/2016 season (21.8%; 95% CI: 18.7-24.0%). CONCLUSIONS There was a correlation between virus circulation, incidence rates for each age group and the previous seroprotection for seasonal influenza viruses.Our study highlights the value of measuring the serological profile for influenza to establishe risk groups for infection for which an increase preventive measures, including vaccination, should be fostered.info:eu-repo/semantics/publishedVersio

Protocol Proposal For The Care Of The Person With Venous Ulcer

Objective: To propose a care protocol for the care of the person with a venous ulcer in highly complex services. Methods and results: This is a methodological study, in three stages: literature review, validation of content and validation in the clinical context. The literature review was carried out from June to August/2011, being the basis for the construction of the Protocol for Venous Ulcers. The content validation included 53 judges (44 nurses, 8 physicians and 1 physiotherapist) selected through the Lattes platform to evaluate the items of the protocol. Validation in the clinical context occurred at the University Hospital Onofre Lopes, in Natal/RN with four judges (nurses), who worked in pairs, evaluating 32 patients with venous ulcers. The protocol was validated with 15 categories: sociodemographic data; anamnesis; examinations; ulcer characteristics; care with the lesion and perilesional area; medicines used to treat the lesion; evaluation and treatment of pain; surgical treatment of chronic venous disease; recurrence prevention (clinical and educational strategies); reference; counter-reference; and quality of life. Conclusion: The validated protocol regarding content and clinical context was applicable. Its implementation is a viable measure that assists in the reorientation of the team in high complexity services, aiming at wound healing and restoration of the patient´s integral health. Keywords: Varicose ulcer; Tertiary Health Care; Protocols; Validation studies

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio