1,090 research outputs found
An Organopalladium-pvc Membrane For Sulphur Dioxide Optical Sensing
No full textThe development of a sensing membrane for the determination of gaseous sulphur dioxide is described. An organopalladium complex, Pd2(dpm) 2Cl2 (dichloro-bis-(diphenylphosphine)-methane dipalladium I), was immobilised in a poly(vinyl chloride) thin film plasticised with ortho-nitrophenyloctylether (o-NPOE). Several membranes were prepared, using 20, 25 and 30% of PVC; 1, 5 and 8% of palladium complex and enough o-NPOE to make a total of 100 mg, which was dissolved in 1.0 mL of THF. The sensing membranes were obtained by manual deposition of 10, 15 and 20 μL of the solution onto cellulose acetate films, which were left to dry for 24 h and then stored in a desiccator sheltered from ambient light. The membrane was placed in an acrylic flow cell, in which the common end of a bifurcated optical fibre bundle was adapted and placed 1 mm from the membrane. Reflectance measurements were performed from 400 to 800 nm, after exposing the membrane to 0 to 500 ppm v of SO2 in air, at a flow rate of 500 mL min -1. The membrane composed of 20% PVC, 72% o-NPOE and 8% palladium complex showed the best performance and the film prepared from 20 μl of solution provided the highest signal (ca 160 mV upon exposure to 500 ppm v SO2). Measurements made at 530 nm showed a linear response range up to 300 ppmv, with a detection limit of 3.5 ppm v. By employing a flow rate of 500 mL min-1, response times (t90%) of 3 and 2 min were obtained for reaction of the membrane with SO2 and for reverse response upon exposure to dry nitrogen, respectively. Although the palladium complex also reacts with carbon monoxide in solution, this interference was not observed for concentrations up to 1000 ppmv of CO. The membrane showed a lifetime of ca. 2 months when stored in a desiccator. © 2004 Elsevier B.V. All rights reserved.1071 SPEC. ISS.4752http://www.epa.gov/air/airtrends/sulfur2.html, accessed on 11/march/2004Kuratli, M., Pretsch, E., Sulfur dioxide-selective optodes (1994) Anal. Chem., 66, pp. 85-91Carballo, R., Dall'Orto, V.C., Lo Balbo, A., Rezzano, I., Determination of sulfide by flow injection analysis using a poly [Ni-(protoporphyrin IX)] chemically modified electrode (2003) Sens. Actuators B, 88, pp. 155-161Chiou, C.Y., Chou, T.C., Amperometric SO2 gas sensor based on solid polymer electrolytes (2002) Sens. Actuators B, 87, pp. 1-7Li, H., Wang, Q.J., Xu, J.M., Zhang, W., Jin, L.T., A novel nano-Au- assembled amperometric SO2 gas sensor: Preparation, characterization and sensing behavior (2002) Sens. Actuators B, 87, pp. 18-24Hodgson, A.W.E., Jacquinot, P., Hauser, P.C., Electrochemical sensor for the detection of SO2 in low-ppb range (1999) Anal. Chem., 71, pp. 2831-2837Matsuguchi, M., Tamai, K., Sakai, Y., SO2 gas sensors using polymers with different amino groups (2001) Sens. Actuators B, 77, pp. 363-367Guimarães, M.O., Detection of sulfur dioxide using piezoelectric quartz crystal microbalance (1997) Anal. Lett., 30, pp. 2159-2174Mohr, G.J., Draxler, S., Trznadel, K., Lehmann, F., Lippitsch, M.E., Synthesis and characterization of fluorophore-absorber pairs for sensing of ammonia based on fluorescence (1998) Anal. Chim. Acta, 360, pp. 119-128Raimundo Jr., I.M., Narayanaswamy, R., Simultaneous determination of relative humidity and ammonia in air employing an optical fibre sensor and artificial neural network (2001) Sens. Actuators B, 74, pp. 60-68Choi, M.M., Xiao, D., Oxygen-sensitive reverse-phase optode membrane using silica gel-absorbed ruthenium (II) complex embedded in gelatin film (1999) Anal. Chim. Acta, 387, pp. 197-205Miller, B., Hauser, P.C., Fluorescence optical sensor for low concentrations of dissolved carbon dioxide (1996) Analyst, 121, pp. 339-343Freeman, M.K., Bachas, L.G., Fiber optic sensor for NOx (1992) Anal. Chim. 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Chem., 374, pp. 1159-1164Papkovsky, D., Uskova, M.A., Ponomarev, G.V., Korpela, T., Kulmala, S., Guilbault, G.G., Optical sensing of sulfite with a phosphorescent probe (1998) Anal. Chim. Acta, 374, pp. 1-9Gimenez, I.F., Alves, O.L., Immobilisation of complexes containing metal-metal bonds in porous Vycor glass and subsequent insertion of gas molecules into the Pd-Pd bonds (2002) Glass Technol., pp. 166-169Benner, L.S., Olmstead, M.M., Hope, H., Balch, A.L., Reversible insertion of sulfur dioxide into palladium-palladium bonds. the preparation and structure of Pd2(μ-SO2) (Ph 2PCH2PPh2)2Cl2 (1978) J. Organomet. Chem., 153, pp. 31-35Benner, L.S., Balch, A.L., Novel reactions of metal-metal bonds. Insertion of isocyanides and carbon monoxide into the palladium-palladium bond of some Pd (I) dimmers (1978) J. Am. Chem. Soc., 13, pp. 6099-6106Balch, A.L., Benner, L.S., Olmstead, M.M., Novel reactions of metal-metal bonds. 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Ocorrência de maloclusões em pré-escolares de 2 a 5 anos de idade, Florianópolis, SC, Brasil
No full textTCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências da Saúde. Odontologia.Objetivo: Este trabalho propõe verificar a ocorrência de mordida aberta anterior, overjet acentuado, mordida cruzada posterior e associar essas maloclusões com gênero, idade, trauma dental e comprometimento estético em pré-escolares na faixa etária de dois a cinco anos de idade em Florianópolis, SC, Brasil. Metodologia: Este estudo transversal foi realizado em 239 pré-escolares selecionados aleatoriamente em escolas municipais após autorização dos pais e/ou responsáveis. A coleta de dados se deu por meio de exame clínico da criança realizado por três examinadores previamente calibrados (Kappa>0,7) para detectar a presença de maloclusão. Os dados obtidos foram tabulados e verificou-se as associações entre as variáveis com o teste Qui-quadrado. Resultados: Foram examinados 129 meninos (53,97%) e 110 meninas (46,02%). Dentre as crianças, 33,18% tinha entre 2 e 3 anos, 66,8% entre 4 e 5 anos de idade, 8,78% apresentaram mordida aberta anterior ≥3mm, 35,98% overjet ≥3mm e 8,36% apresentaram mordida cruzada posterior (uni ou bilateral). A associação da mordida aberta anterior e do overjet com o comprometimento estético teve resultado estatisticamente significativo (p0,05). Conclusão: Conclui-se que há relação entre mordida aberta anterior e overjet com comprometimento estético nos pré-escolares examinados.Objective: This study proposes to assess the occurrence of anterior open bite, accentuated overjet and posterior crossbite and associate these malocclusions with gender, age, dental trauma and esthetic impairment in preschool children aged two to five years of age in Florianópolis, SC, Brazil. Methods: This cross-sectional study was conducted in 239 preschoolers randomly selected in public schools after permission from parents and/or guardians. The collection was made by clinical examination of the child conducted by three calibrated examiners (Kappa>0,7) to detect the presence of malocclusion. Data were tabulated and it was found associations between variables with the Chi-square test. Results: 129 male (53,97%) and 110 females (46,02%) were examined. Among children, 33,18% had between 2 and 3 years, 66,8% between 4 and 5 years old, 8,78% showed anterior open bite ≥3mm, 35,98% had overjet ≥3mm and 8,36% showed posterior crossbite (unilateral or bilateral). The association of anterior open bite and overjet with the aesthetic impairment showed a significant result (p0,05). Conclusion: It is concluded there are relationship between anterior open bite and overjet with esthetic impairment in preschool children examined
Search for exclusive decays of the baryon and measurement of its mass
No full textA search for fully reconstructed \lb beauty baryons is performed using about 3 million Z decays collected with the DELPHI detector at LEP. The analysis relies on the combined use of the accurate tracking and of the hadron identification capabilities of DELPHI. A total of four events has been found, three in the \lc\ppm channel and one in the \lc\a1m channel over a small background. The \lb beauty baryon mass is measured to be (~ 5668 \pm 16~ ({\rm stat.}) \pm 8~({\rm syst.})~)~ \mv
Determinación de hemoglobinopatías y anemia ferropénica en población estudiantil Afrodescendiente de la Universidad Colegio Mayor de Cundinamarca
No full textLa población afrodescendiente en Colombia va en constante crecimiento cada año según cifras del DANE y como consecuencia las enfermedades genéticas asociadas a dicha etnia, lo que representa un grave problema de salud pública en el mundo, según la organización mundial de la salud las hemoglobinopatías se encuentran en un 71% de los países y cada año nacen en el mundo 330.000 niños afectados con este tipo de alteraciones en su molécula de hemoglobina, afectando principalmente a los ya denominados afrodescendientes, los cuales se encuentran en su mayoría en países del sur del continente americano como: Brasil, Cuba, Ecuador, Costa rica, Colombia, entre otros. En Colombia el porcentaje de población afrodescendientes corresponde al 10,4% según el censo realizado en 2005 por el DANE lo que corresponde a un total de 4’311.757 habitantes, esto acompañado por desplazamiento (6.3 %) y migración por violencia (6.8%) realizado por estas comunidades , ha contribuido al aumento de intercambio genético y con ello la aparición de hemoglobinopatías en el país, en cuanto a la anemia por deficiencia de hierro, tiene una prevalencia en el país de entre el 20 - 39,9% en la población afrocolombiana, en el mismo censo realizado por el DANE en el año 2005 el 14,32% (612.194 personas) de la población negra y afrocolombiana declararon haber pasado días de ayuno en la semana previa al Censo 6,49,50. Este trabajo tiene como objetivo determinar hemoglobinopatías y anemia ferropénica en población Afrodescendiente de la Universidad Colegio Mayor de Cundinamarca mediante el examen de frotis de sangre periférico, cuadro hemático, ferritina, electroforesis de hemoglobina ácida y alcalina, en esta forma se identificaron portadores sanos de beta-talasemia, hemoglobina C y deficiencias subclínicas de hierro. Además, se concientizo a la población en estudio sobre la necesidad de una consejería genética.1. Antecedentes 13
2. Marco teórico 25
2.1 Eritrocito 25
2.2 Molécula de hemoglobina 25
2.3 Anemia 26
2.4 Anemia ferropénica 27
2.5 Ferritina 28
2.6 Transferrina 29
2.7 Receptores solubles de transferrina 29
2.8 Hierro sérico 30
2.9 Estados de deficiencia del hierro 31
2.10 Metabolismo del hierro 33
2.11 Hemoglobinopatías 34
2.12 Electroforesis de hemoglobina 39
3. Diseño metodológico 40
3.1 Diseño muestral y tipo de investigación 40
3.2 Universo 40
3.3 Muestra 41
3.4 Variables 41
3.5 Técnicas y parámetros para recolección de la información 41
3.6 Procedimiento 43
4. Reporte y análisis de resultados 45
5. Discusión 59
6. Conclusiones 64
7. Referencias 66PregradoBacteriólogo(a) y Laboratorista ClínicoTrabajo de grad
Afectación económica de la tuberculosis en la producción ganadera y la salud pública
No full textLa tuberculosis bovina es una enfermedad zoonótica que tiene un gran impacto en el sector económico y en la salud pública. Es causada por el Mycobacterium bovis perteneciente al complejo Mycobacterium tuberculosis, el cual tiene una mayor afectación en el ganado bovino y poco frecuente en bufalinos, caprinos y venados. En la actualidad, principalmente en los países en desarrollo, no se conoce con claridad la magnitud de esta enfermedad en los humanos cuando es causada por Mycobacterium bovis; ya que es subnotificada por las limitaciones que existen en los laboratorios de diagnósticos, que impiden la diferenciación entre Mycobacterium bovis del Mycobacterium tuberculosis. Esta revisión pretende mostrar el impacto económico de la tuberculosis bovina en las producciones ganaderas y en la salud pública.Bovine tuberculosis is a zoonotic disease that has a great impact on the economic sector and public health. It is caused by Mycobacterium bovis belonging to the Mycobacterium tuberculosis complex, which is more common in cattle and rare in buffalo, goats and deer. Currently, mainly in developing countries, the magnitude of this disease in humans when caused by Mycobacterium bovis is not clearly known; since it is underreported due to the limitations that exist in diagnostic laboratories, which prevent the differentiation between Mycobacterium bovis and Mycobacterium tuberculosis. This review aims to show the economic impact of bovine tuberculosis on livestock production and public healthIntroducción. -- Reseña historia sobre la tuberculosis. -- Generalidades de la Tuberculosis. -- Patogenia. -- Diseminación post primaria. -- Sintomatología . -- Transmisión. -- Transmisión a los seres humanos. -- Importancia de la tuberculosis bovina. -- Situación actual de la tuberculosis a nivel internacional. -- Situación de la tuberculosis en Colombia. -- A. Impacto económico en las producciones. -- Impacto comercio interior y exterior. -- B. Impacto económico en la salud publica. -- Discusión. -- Conclusión. -- Revisión bibliográ[email protected]@campusucc.edu.c
Search for SUSY with R-parity violating LL anti-E couplings at s**(1/2) = 189-GeV
No full textSearches for pair production of supersymmetric particles under the assumption that R-parity is not conserved are presented, based on data recorded by the DELPHI detector in 1998 from e+e- collisions at a centre-of-mass energy of 189 GeV. Only one R-parity violating LLĒ term (i.e. one l coupling), which couples scalar leptons to leptons, is considered to be dominant at a time. Moreover, it is assumed that the strength of the R-parity violating couplings is such that the lifetimes can be neglected. The search for pair production of neutralinos, charginos and sleptons has been performed for both direct R-parity violating decays and indirect cascade decays. The results are in agreement with Standard Model expectations, and are used to update the constraints on the MSSM parameter values and the mass limits previously derived at √s =183 GeV. The present 95% C.L. limits on supersymmetric particle masses are: mx∼0 > 30GeV/c2 and mx∼± > 94 GeV/c2; mv∼ > 76.5GeV/c2 (direct and indirect decays); ml∼R > 83GeV/c2 (indirect decay only).0info:eu-repo/semantics/publishe
Alternativas para a auto-sustentabilidade dos xokleng da Terra Indígena Ibirama
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção
Search for heavy diboson resonances in semileptonic final states in pp collisions at s=13 TeV with the ATLAS detector
No full textThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/
Evidence for Electroweak Production of W(+/-)W(+/-)jj in pp Collisions at root s=8 TeV with the ATLAS Detector
No full textFurther distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.This Letter presents the first study of W±W±jj, same-electric-charge diboson production in association with two jets, using 20.3 fb-1 of proton-proton collision data at √s=8 TeV recorded by the ATLAS detector at the Large Hadron Collider. Events with two reconstructed same-charge leptons (e±e±, e±μ±, and μ±μ±) and two or more jets are analyzed. Production cross sections are measured in two fiducial regions, with different sensitivities to the electroweak and strong production mechanisms. First evidence for W±W±jj production and electroweak-only W±W±jj production is observed with a significance of 4.5 and 3.6 standard deviations, respectively. The measured production cross sections are in agreement with standard model predictions. Limits at 95% confidence level are set on anomalous quartic gauge couplings
Higgs boson production cross-section measurements and their EFT interpretation in the 4 ℓ decay channel at √s= 13 TeV with the ATLAS detector
No full textHiggs boson properties are studied in the four-lepton decay channel (where lepton = e, μ) using 139 fb - 1 of proton–proton collision data recorded at s=13 TeV by the ATLAS experiment at the Large Hadron Collider. The inclusive cross-section times branching ratio for H→ ZZ∗ decay is measured to be 1.34 ± 0.12 pb for a Higgs boson with absolute rapidity below 2.5, in good agreement with the Standard Model prediction of 1.33 ± 0.08 pb. Cross-sections times branching ratio are measured for the main Higgs boson production modes in several exclusive phase-space regions. The measurements are interpreted in terms of coupling modifiers and of the tensor structure of Higgs boson interactions using an effective field theory approach. Exclusion limits are set on the CP-even and CP-odd ‘beyond the Standard Model’ couplings of the Higgs boson to vector bosons, gluons and top quarks. © 2020, The Author(s)
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