27 research outputs found
Water-based electrolytes for dye-sensitized solar cells
No full textStable and efficient dye-sensitized solar cells based on water-containing electrolytes are shown. For water contents up to 40percent, no decrease in efficiency is seen. The cells are demonstrated to be stable for long periods of continuous illumination.This work lays a foundation for the further development of water-based cells for commercial production. © 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.ANDERSON MA, 1988, J MEMBRANE SCI, V39, P243, DOI 10.1016-S0376-7388(00)80932-1; 'Regan B. O., 1991, NATURE, V353, P737, DOI [DOI 10.1038-353737A0, 10.1038-353737a0]; Ardo S, 2009, CHEM SOC REV, V38, P115, DOI 10.1039-b804321n; Barnes PRF, 2009, NANO LETT, V9, P3532, DOI 10.1021-nl901753k; Barnes PRF, 2009, J PHYS CHEM C, V113, P1126, DOI 10.1021-jp809046j; Green MA, 2009, PROG PHOTOVOLTAICS, V17, P320, DOI 10.1002-pip.911; Hagfeldt A, 2000, ACCOUNTS CHEM RES, V33, P269, DOI 10.1021-ar980112j; Jung YS, 2009, ELECTROCHIM ACTA, V54, P6286, DOI 10.1016-j.electacta.2009.06.006; JURIS A, 1988, COORDIN CHEM REV, V84, P85, DOI 10.1016-0010-8545(88)80032-8; Kaneko M, 2003, MACROMOL RAPID COMM, V24, P444, DOI 10.1002-marc.200390059; Koops SE, 2009, J AM CHEM SOC, V131, P4808, DOI 10.1021-ja8091278; LISKA P, 1988, J AM CHEM SOC, V110, P3686, DOI 10.1021-ja00219a068; Liu Y, 1998, SOL ENERG MAT SOL C, V55, P267, DOI 10.1016-S0927-0248(98)00111-1; Macht B, 2002, SOL ENERG MAT SOL C, V73, P163, DOI 10.1016-S0927-0248(01)00121-0; Matar F, 2008, J MATER CHEM, V18, P4246, DOI 10.1039-b808255c; Mikoshiba S, 2005, CURR APPL PHYS, V5, P152, DOI 10.1016-j.cap.2004.06.023; NAZEERUDDIN MK, 1990, HELV CHIM ACTA, V73, P1788, DOI 10.1002-hlca.19900730624; OREGAN BC, 1990, THESIS U WISCONSIN; O'Regan BC, 2004, J PHYS CHEM B, V108, P4342, DOI 10.1021-jp035613n; O'Regan BC, 2009, J AM CHEM SOC, V131, P3541, DOI 10.1021-ja806869x; O'Regan BC, 2007, J PHYS CHEM C, V111, P14001, DOI 10.1021-jp073056p; Saito H, 2004, ELECTROCHEMISTRY, V72, P310; Tropsha YG, 1997, J PHYS CHEM B, V101, P2259, DOI 10.1021-jp9629856; VLACHOPOULOS N, 1988, J AM CHEM SOC, V110, P1216, DOI 10.1021-ja00212a033; Wang P, 2005, APPL PHYS LETT, V86, DOI 10.1063-1.188782554515
Re-evaluation of recombination losses in dye-sensitized cells: The failure of dynamic relaxation methods to correctly predict diffusion length in nanoporous photoelectrodes
No full textPhotocurrents generated by thick, strongly absorbing, dye-sensitized cells were reduced when the electrolyte Iodine concentration was increased. Electron diffusion lengths measured using common transient techniques (L n) were at least two times higher than diffusion lengths measured at steady state (L IPCE). Charge collection efficiency calculated using Ln seriously overpredicted photocurrent, while L IPCE correctly predicted photocurrent. This has implications for optimizing cell design. © 2009 American Chemical Society.Ahn KS, 2007, J APPL PHYS, V101, DOI 10.1063-1.2721976; Barnes PRF, 2009, J PHYS CHEM C, V113, P1126, DOI 10.1021-jp809046j; Barnes PRF, 2009, J PHYS CHEM C, V113, P12615, DOI 10.1021-jp904497c; Bisquert J, 2004, J PHYS CHEM B, V108, P2313, DOI 10.1021-jp035395y; Bisquert J, 2004, J PHYS CHEM B, V108, P2323, DOI 10.1021-jp035397i; Cao YM, 2009, J PHYS CHEM C, V113, P6290, DOI 10.1021-jp9006872; Chiba Y, 2006, JPN J APPL PHYS 2, V45, pL638, DOI 10.1143-JJAP.45.L638; de Jongh PE, 1996, PHYS REV LETT, V77, P3427, DOI 10.1103-PhysRevLett.77.3427; Dor S, 2009, J PHYS CHEM C, V113, P2022, DOI 10.1021-jp808175d; Dunn HK, 2009, J PHYS CHEM C, V113, P4726, DOI 10.1021-jp810884q; Fukai Y, 2007, ELECTROCHEM COMMUN, V9, P1439, DOI 10.1016-j.elecom.2007.01.054; Gao F, 2008, J AM CHEM SOC, V130, P10720, DOI 10.1021-ja801942j; Guo L, 2007, ACTA PHYS SIN-CH ED, V56, P4270; Halme J, 2008, J PHYS CHEM C, V112, P20491, DOI 10.1021-jp806512k; Halme J, 2008, J PHYS CHEM C, V112, P5623, DOI 10.1021-jp711245f; Hamann TW, 2008, J PHYS CHEM C, V112, P10303, DOI 10.1021-jp802216p; Heimer TA, 2000, J PHYS CHEM A, V104, P4256, DOI 10.1021-jp993438y; Huang SY, 1997, J PHYS CHEM B, V101, P2576, DOI 10.1021-jp962377q; Ito S, 2008, THIN SOLID FILMS, V516, P4613, DOI 10.1016-j.tsf.2007.05.090; Jennings JR, 2008, J AM CHEM SOC, V130, P13364, DOI 10.1021-ja804852z; Jennings JR, 2007, J PHYS CHEM C, V111, P16100, DOI 10.1021-jp076457d; Kang MS, 2008, J PHOTOCH PHOTOBIO A, V195, P198, DOI 10.1016-j.jphotochem.2007.10.003; Koops SE, 2009, J AM CHEM SOC, V131, P4808, DOI 10.1021-ja8091278; Kopidakis N, 2003, J PHYS CHEM B, V107, P11307, DOI 10.1021-jp0304475; Kopidakis N., 2006, PHYS REV B, V73, P7; Liu Y, 1998, SOL ENERG MAT SOL C, V55, P267, DOI 10.1016-S0927-0248(98)00111-1; Lobato K, 2006, J PHYS CHEM B, V110, P16201, DOI 10.1021-jp063919z; Madhwani S, 2007, ENERG SOURCE PART A, V29, P721, DOI 10.1080-00908310500280926; Nazeeruddin MK, 2004, LANGMUIR, V20, P6514, DOI 10.1021-la0496082; NAZEERUDDIN MK, 1993, J AM CHEM SOC, V115, P6382, DOI 10.1021-ja00067a063; Nelson I. V., 1964, J ELECTROANAL CHEM, V7, P218, DOI 10.1016-0022-0728(64)80015-2; OREGAN B, 1990, J PHYS CHEM-US, V94, P8720, DOI 10.1021-j100387a017; O'Regan BC, 2008, J AM CHEM SOC, V130, P2906, DOI 10.1021-ja078045o; O'Regan BC, 2006, J PHYS CHEM B, V110, P17155, DOI 10.1021-jp062761f; O'Regan BC, 2009, J AM CHEM SOC, V131, P3541, DOI 10.1021-ja806869x; O'Regan BC, 2007, J PHYS CHEM C, V111, P14001, DOI 10.1021-jp073056p; OREGAN O, ACC CHEM RES UNPUB; Peter LM, 2007, J PHYS CHEM C, V111, P6601, DOI 10.1021-jp069058b; Rao C. N. R., 1972, APPL SPECTROSC, V5, P1, DOI 10.1080-05704927208081699; Schlichthorl G, 1997, J PHYS CHEM B, V101, P8141, DOI 10.1021-jp9714126; Snaith HJ, 2008, NANOTECHNOLOGY, V19, DOI 10.1088-0957-4484-19-42-424003; SODERGREN S, 1994, J PHYS CHEM-US, V98, P5552; Splan KE, 2004, J PHYS CHEM B, V108, P4111, DOI 10.1021-jp037230v; Wang M, 2009, CHEMPHYSCHEM, V10, P290, DOI 10.1002-cphc.200800708; Xia JB, 2007, J PHOTOCH PHOTOBIO A, V188, P120, DOI 10.1016-j.jphotochem.2006.11.02866686
Modern methods of stimulation of angiogenesis in patients with critical limb ischemia (review).
No full textKryvoruchko I. A., Goni S.- K. T., Goni S.- A. T., Antonova M. S., Sykal M. A., Alexandrov M. A. Modern methods of stimulation of angiogenesis in patients with critical limb ischemia (review). Journal of Education, Health and Sport. 2017;7(4):733-745. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.580797
http://ojs.ukw.edu.pl/index.php/johs/article/view/4464
The journal has had 7 points in Ministry of Science and Higher Education parametric evaluation. Part B item 1223 (26.01.2017).
1223 Journal of Education, Health and Sport eISSN 2391-8306 7
© The Author (s) 2017;
This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, Poland
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This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial
use, distribution and reproduction in any medium, provided the work is properly cited.
The authors declare that there is no conflict of interests regarding the publication of this paper.
Received: 12.04.2017. Revised: 10.04.2017. Accepted: 25.04.2017.
MODERN METHODS OF STIMULATION OF ANGIOGENESIS IN PATIENTS WITH CRITICAL LIMB ISCHEMIA (REVIEW)
I. A. Kryvoruchko, S.- K. T. Goni, S.- A. T. Goni, M. S. Antonova, M. A. Sykal,
M. A. Alexandrov
Kharkov National Medical University, Ukraine
Department of Surgery №2
Abstract
The term "critical ischemia of extremities" (critical limb ischemia) was first introduced by P.R.F. Bell in 1982 to refer to a group of diseases accompanied by pain in the legs at rest, trophic ulcers and distal necroses of the lower limbs. Critical ischemia of the lower limbs is a condition of almost complete cessation of arterial blood flow to the tissues of the lower limbs.
If the arterial blood supply is not improved, limb amputation becomes inevitable for all patients. Treatment of ischemia of the lower extremities should be complex and differentiated depending on the stage and features of the course of the disease. Modern approaches to the therapy of lower limb ischemia include conservative and surgical methods of treatment, all of which are aimed at improving blood flow in the affected limbs. In the article modern methods of stimulating angiogenesis in patients with lower limb ischemia and results are shown.
Keywords: critical limb ischemia, cell therapy, gene therapy, angiogenesis stimulatio
Nitrogen Supply To Corn From Sunn Hemp And Velvet Bean Green Manures [fornecimento De Nitrogênio Ao Milho Pelos Adubos Verdes Crotalária Júncea E Mucuna Preta]
No full textDue to their nitrogen fixation potential, legumes represent an alternative for supplying nutrients, substituting or complementing mineral fertilization in cropping systems involving green manuring. The objective of this study was to evaluate the N balance in a soil-plant system involving green manures [sunn hemp (Crotalaria juncea L.) and velvet bean (Mucuna aterrima Piper & Tracy)], both labeled with 15N. They were incorporated into two soils of contrasting textural classes: A clayey Eutrudox and a sandy-clayey Paleudalf, both cultivated with corn. The research was carried out in a greenhouse, using pots containing 6 kg of air dried soil, to which the equivalent to 13 Mg ha-1 dry matter of above-ground mass plus 2.7 or 2.2 Mg ha-1 of velvet bean and sunn hemp roots were incorporated, respectively, with 15N labeling of either shoots or roots. One hundred days after emergence of the corn, the velvet bean residues provided higher accumulation of N in the soil, higher absorption by corn plants and accumulation in the shoot. The green manure decomposition was more intense in the medium-textured Paleudalf. The highest nitrogen losses were also observed in this soil.663386394Allison, F.E., (1966) The Fate of Nitrogen Applied to Soils Advances in AgronomyAmbrosano, E.J., Avaliação do crescimento e aproveitamento de fertilizante nitrogenado pelo capim colonião var (1989) Tobiatã em diferentes épocas, p. 110. , Piracicaba: USP/ESALQ, Dissertação (Mestrado)Ambrosano, E.J., Dinâmica do nitrogênio dos adubos verdes, crotalária júncea (Crotalaria juncea) e mucuna-preta (Mucuna aterrima) em dois solos cultivados com milho (1995), p. 83. , Piracicaba: USP/ESALQ, Tese (Doutorado)Ambrosano, E.J., Trivelin, P.C.O., Muraoka, T., Técnica para marcação dos adubos verdes crotalária júncea e mucuna-preta, com 15N para estudos de dinâmica do nitrogênio (1997) Bragantia, 56, pp. 219-224Ambrosano, E.J., Trivelin, P.C.O., Cantarella, H., Ambrosano, G.M.B., Muraoka, T., Nitrogen mineralization in soils amended with sunnhemp, velvet bean and common bean residues (2003) Scientia Agricola, 60, pp. 133-137Ambrosano, E.J., Trivelin, P.C.O., Cantarella, H., Ambrosano, G.M.B., Schammas, E.A., Guirado, N., Rossi, F., Muraoka, T., Utilization of nitrogen from green manure and mineral fertilizer by sugarcane (2005) Scientia Agricola, 62, pp. 534-542Azam, F., Malik, K.A., Sajjad, M.I., Transformations in soil and availability to plants of 15N applied as inorganic fertilizer and legume residues (1985) Plant and Soil, 86, pp. 3-13Azam, F., Malik, K.A., Sajjad, M.I., Uptake by wheat plants and turnover within soil fractions of residual N from leguminous plant material and inorganic fertilizer (1986) Plant and Soil, 95, pp. 97-108Bartholomew, W.V., Mineralization and immobilization of nitrogem in the decomposition of plant and animal residues (1965) Soil Nitrogen. Madison: American Society of Agronomy, pp. 287-306. , In: BARTHOLOMEW, W.V.CLARK, F.E. (Ed.), (Agronomy Monograph, 10)Bayer, C., Mielniczuk, J., Martin-Neto, L., Errnani, P.R., Stocks and humification degree of organic matter fractions as affected by no-tillage on subtropical soil (2002) Plant and Soil, 238, pp. 133-140Bremner, J.M., Nitrogen-total (1996) Methods of Soil Analysis, pp. 1085-1121. , In: SPARKS, D.L. (Ed.), Madison: Soil Science Society of AmericaBuresh, R.J., Austin, E.R., Craswell, E.T., Analytical methods in 15N research (1982) Fertilizer Research, 3, pp. 337-62Calvache Ulloa, A.M., Libardi, P.L., Reichardt, K., (1982) Utilização do nitrogênio fertilizante por dois híbridos de milho, p. 66. , Campinas: Fundação CargillFarquhar, G.D., Wetselaar, R., Firth, P.M., Ammonia volatilization from senescing leaves of maize (1979) Science, 203, pp. 257-1258Flores, L.M., Avaliação quantitativa da eficiência de utilização de duas fontes de nitrogênio, CO(15NH2)2 e (15NH4)2SO4 pela cultura de milho (Zea mays L.) (1986), p. 103. , Piracicaba: USP/ESALQ, Dissertação (Mestrado)Gallo, P.B., Sawazaki, E., Hiroce, R., Mascarenhas, H.A.A., Produção de milho afetada pelo nitrogênio mineral e cultivos anteriores com soja (1983) Revista Brasileira de Ciência do Solo, 7, pp. 149-152Gallo, P.B., Mascarenhas, H.A.A., Bataglia, O.C., Quaggio, J.A., Interação calagem-adubação nitrogenada na produção de sorgo sob deficiência hídrica em rotação com soja (1986) Bragantia, 45, pp. 231-238Harris, G.H., Hesterman, O.B., Quantifying the nitrogen contribution from alfafa to soil and two succeeding crops using nitrogen-15 (1990) Agronomy Journal, 82, pp. 129-134(1976) Tracer Manual on Crops and Soils, p. 277. , INTERNATIONAL ATOMIC ENERGY AGENCY - IAEA, Viena: IAEA, (Technical Reports Series, 171)Jans-Hammermeister, D.C., McGill, W.B., Jensen, T.L., Nitrogen accumulations and relative rates of mineralization in two soils following legume green manuring (1993) Canadian Journal of Soil Science, 74, pp. 23-28Ng Kee Kwong, K.F., Deville, J., Application of 15N- labelled urea to sugar cane through a drip-irrigation system in Mauritius (1994) Fertilizer Research, 39, pp. 223-228Kanthack, R.A.D., Mascarenhas, H.A.A., Castro, O.M., Tanaka, R.T., Nitrogênio aplicado em cobertura no milho após tremoço (1991) Pesquisa Agropecuária Brasileira, 26, pp. 99-104Ladd, J.N., Oades, J.M., Amato, M., Microbial biomass formed from 14C, 15N-labelled plant material decomposing in soils in the field (1981) Soil Biology & Biochemistry, 13, pp. 119-126Ladd, J.N., Oades, J.M., Amato, M., Distribution and recovery of nitrogen from legume residues decomposing in soils sown to wheat in the field (1981) Soil Biology & Biochemistry, 13, pp. 251-256Ladd, J.N., Amato, M., Jackson, R.B., Butler, J.H.A., Utilization by wheat crops of nitrogen from legume residues decomposing in soils in the field (1983) Soil Biology & Biochemistry, 15, pp. 231-238Mascarenhas, H.A.A., Tanaka, R.T., Costa, A.A., Rosa, F.V., Costa, V.F., (1994) Efeito residual das leguminosas sobre o Campinas: Instituto Agronômico de Campinas, p. 15. , (Boletim Científico IAC, 32)Montojos, J.C., Gargantini, H., Fixação do nitrogênio do ar pelas bactérias que vivem em simbiose com as raízes das leguminosas (1963) Bragantia, 22, pp. 731-739Muller, M.M., Sundman, V., The fate of nitrogen (15N) released from different plant materials during decomposition under field conditions (1988) Plant and Soil, 105, pp. 133-139Pereira, J.C.V.N.A., Mascarenhas, H.A.A., Martins, A.L.M., Braga, N.R., Sawazaki, E., Gallo, P.B., Efeito da adubação nitrogenada em cobertura no cultivo contínuo do milho e do algodão e em rotação com soja (1988) Revista de Agricultura, 63, pp. 95-108Proksch, G., Routine analysis of 15N in plant material by mass-spectrometry (1969) Plant and Soil, 31, pp. 380-384Rittenberg, D., The preparation of gas sample for mass-spectrometric analysis (1946) Preparation and Measure of Isotopic Tracers, p. 31. , In WILSON, D.W. (Ed), Ann Arbor: EdwadsSilva, P.R.F., Stutte, C.A., Nitrogen loss in conjunction with transpiration from rice leaves as influenced by growth stage, leaf position and N supply (1981) Agronomy Journal, 73, pp. 38-48Silva, R., Potencial da mucuna preta como adubo verde para o arroz-de-sequeiro em latossolo amarelo da amazônia (1991), p. 136. , Piracicaba: USP/ESALQ, Tese (Doutorado)Silva, E.C., Manejo da adubação nitrogenada e utilização do nitrogênio (15N) da uréia, do milheto e da crotalária pelo milho sob semeadura direta em solo de cerrado (2005), p. 136. , Piracicaba: USP/CENA, Tese (Doutorado)Scivittaro, W.B., Muraoka, T., Boaretto, A.E., Trivelin, P.C.O., Transformações do nitrogênio proveniente de mucuna-preta e uréia utilizados como adubo na cultura do milho (2003) Pesquisa Agropecuária Brasileira, 38, pp. 1427-1433Stevenson, F.J., Organic forms of soil nitrogen (1982) Nitrogen in Agricultural Soils, pp. 67-122. , In: STEVENSON, F.J. (Ed.), Madison: American Society of Agronomy, (Agronomy Monograph, 22)Stevenson, F.J., (1994) Humus Chemistry: Genesis, Composition, Reactions, pp. 59-95. , 2 ed. New York: John WileyStutte, C.A., Weiland, R.T., Blem, A.R., Gaseous nitrogen loss from soybean foliage (1979) Agronomy Journal, 71, pp. 95-97Ta, T.C., Faris, M.A., Availability of N from 15N labelled alfafa residues to three succeeding barley crops under field conditions (1990) Soil Biology & Biochemistry, 22, pp. 835-838Tanaka, R.T., Mascarenhas, H.A.A., Dias, O.S., Campidelli, C., Bulisani, E.A., Cultivo da soja após incorporação de adubo verde e orgânico (1992) Pesquisa Agropecuária Brasileira, 27, pp. 1477-1483Trivelin, P.C.O., Salati, E., Matsui, E., Preparo de amostras para análise de 15N por espectrometria de massas (1973), p. 41. , Piracicaba: USP/CENA, (Boletim Técnico, 2)Trivelin, P.C.O., Lara Cabezas, W.A.R., Victotia, R.L., Reichardt, K., Evaluation of a 15N plot design for estimating plant recovery of fertilizer nitrogen applied to sugar cane (1994) Scientia Agricola, 51, pp. 226-234Villas Bôas, R.L., Alternativas para aumento da recuperação do nitrogênio da uréia pelo milho (Zea mays L) (1990), p. 78. , Piracicaba: USP/CENA, Dissertação (Mestrado
Do counter electrodes on metal substrateswork with cobalt complex based electrolyte in dye sensitized solar cells?
No full textYes. Testing 7 different metals as a substrate for a counter electrode in dye sensitized solar cells (DSSC) showed that some metals can be a good option for use with cobalt electrolyte. It was found that Stainless steels 304 and 321 as well as Ni and Ti suit well to the counter electrodes in DSSCs with cobalt electrolyte. In these 4 cases both the efficiency and the lifetime were similar to the reference cells on conducting glass substrates. In contrast, the cells with Al, Cu and Zn substrates suffered from both a low efficiency and a poor stability. These three metals had clear marks of corrosion such as apparent corrosion products in the aged cells. Additionally, we also investigated how the different types of catalyst materials perform in the case of a metal counter electrode (stainless steel 304) with cobalt electrolyte in comparison to reference glass cells. Among the 5 different catalyst layers the best results for stainless steel electrode were achieved with low temperature platinization whereas polymer catalysts poly(3,4-ethylenedioxythiophene)-ptoluenesulfone and poly(3,4-ethylenedioxythiophene)-polystyrenesulfone that worked well on the glass worked very poorly on the metal. © 2012 The Electrochemical Society.Chen CM, 2010, ELECTROCHIM ACTA, V55, P1687, DOI 10.1016-j.electacta.2009.10.050; Fang X., 2005, THIN SOLID FILMS, V427, P242; Feldt SM, 2010, J AM CHEM SOC, V132, P16714, DOI 10.1021-ja1088869; Hashmi G, 2011, RENEW SUST ENERG REV, V15, P3717, DOI 10.1016-j.rser.2011.06.004; Ito S, 2005, CHEM COMMUN, P4351, DOI 10.1039-b505718c; Jennings JR, 2011, PHYS CHEM CHEM PHYS, V13, P6637, DOI 10.1039-c0cp02605k; Kalowekamo J, 2009, SOL ENERGY, V83, P1224, DOI 10.1016-j.solener.2009.02.003; Kroon JM, 2007, PROG PHOTOVOLTAICS, V15, P1, DOI 10.1002-pip.707; Law CH, 2010, ADV MATER, V22, P4505, DOI 10.1002-adma.201001703; Li DM, 2010, ADV FUNCT MATER, V20, P3358, DOI 10.1002-adfm.201000150; Liberatore M, 2009, APPL PHYS LETT, V94; Liu JY, 2011, ENERG ENVIRON SCI, V4, P3021, DOI 10.1039-c1ee01633d; Ma TL, 2004, J ELECTROANAL CHEM, V574, P77, DOI 10.1016-j.jelechem.2004.08.002; Miettunen K, 2011, J ELECTROANAL CHEM, V653, P93, DOI 10.1016-j.jelechem.2010.12.022; Miettunen K, 2010, J ELECTROCHEM SOC, V157, pB814, DOI 10.1149-1.3374645; Miettunen K, 2007, P 22 EUR PHOT SOL EN, P512; Miettunen K, 2010, CARBON, V49, P528; Reynolds GJ, 2011, ECS TRANSACTIONS, V33, P129, DOI 10.1149-1.3553355; Sapp SA, 2002, J AM CHEM SOC, V124, P11215, DOI 10.1021-ja027355y; Toivola M, 2006, SOL ENERG MAT SOL C, V90, P2881, DOI 10.1016-j.solmat.2006.05.002; Tsao HN, 2011, ENERG ENVIRON SCI, V4, P4921, DOI 10.1039-c1ee02389f; XU WW, 1990, MATER RES BULL, V25, P1385, DOI 10.1016-0025-5408(90)90221-M; Yella A, 2011, SCIENCE, V334, P629, DOI 10.1126-science.120968879
Extracellular electrical recording of pH-triggered bursts in C6 glioma cell populations
No full textGlioma patients often suffer from epileptic seizures because of the tumor's impact on the brain physiology. Using the rat glioma cell line C6 as a model system, we performed long-term live recordings of the electrical activity of glioma populations in an ultrasensitive detection method. The transducer exploits large-area electrodes that maximize double-layer capacitance, thus increasing the sensitivity. This strategy allowed us to record glioma electrical activity. We show that although glioma cells are nonelectrogenic, they display a remarkable electrical burst activity in time. The low-frequency current noise after cell adhesion is dominated by the flow of Na+ ions through voltage-gated ion channels. However, after an incubation period of many hours, the current noise markedly increased. This electric bursting phenomenon was not associated with apoptosis because the cells were viable and proliferative during the period of increased electric activity. We detected a rapid cell culture medium acidification accompanying this event. By using specific inhibitors, we showed that the electrical bursting activity was prompted by extracellular pH changes, which enhanced Na+ ion flux through the psalmotoxin 1-sensitive acid-sensing ion channels. Our model of pH-triggered bursting was unambiguously supported by deliberate, external acidification of the cell culture medium. This unexpected, acidosis-driven electrical activity is likely to directly perturb, in vivo, the functionality of the healthy neuronal network in the vicinity of the tumor bulk and may contribute to seizures in glioma patients
Caracterização de bactérias endofíticas e isolamento do fitopatógeno Exserohilum turcicum de Milho Crioulo (Zea mays var. Rosado)
No full textTCC (graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Agrárias. Curso de Agronomia.O milho representa uma cultura de grande importância para o Brasil, tanto no aspecto econômico como social. Entretanto, o aumento da produção traz consigo condições mais favoráveis para o aparecimento de doenças. Devido às grandes perdas na produção que essas doenças, como a queima de turcicum, podem acarretar na cultura do milho realizam-se cada vez mais aplicações de agroquímicos visando controlar tais moléstias. Entretanto, estas aplicações geram grandes problemas tanto sociais como ambientais, levando-nos a buscar soluções mais sustentáveis. Neste contexto, apesar de ainda pouco estudados, os microrganismos endofíticos, devido ao nicho ecológico que ocupam, vem mostrando potencial de uso na agricultura inclusive no controle biológico. Deste modo, este trabalho teve como objetivo realizar o isolamento e a caracterização de bactérias endofíticas de milho crioulo variedade Rosado e o isolamento do fungo Exserohilum turcicum (Pass.) K. J. Leonard & E. G. Suggs, agente causal da queima de turcium, para que futuramente possam ser testados esses isolados bacterianos no antagonismo ao patógeno. Para tanto através do método de fragmentação do tecido vegetal, foram isoladas assepticamente em meio TSA 10% bactérias endofíticas de folhas e colmos de milho crioulo no estádio vegetativo da cultura, realizando-se posteriormente a caracterização morfológica e molecular por BOX PCR, dos isolados obtidos. O isolado fúngico foi também isolado da folha, a partir de lesões típica da doença, utilizando-se o meio LCHA. No total, foram isolados 82 bactérias endofíticas, onde 56 foram provenientes de folha e 26 de colmo. Até o presente momento foi possível realizar a caracterização morfológica e molecular de 28 isolados, sendo 14 de cada órgão vegetal. A análise morfológica diferiu da molecular. Entretanto, esta última demonstrou que dos 28 isolados, 10 isolados de colmo e 12 isolados de folha, são diferentes e apenas 1 isolado comum tanto a folha quanto a colmo. Deste modo, a análise por BOX-PCR, mostrou-se um método eficiente para diferenciar isolados, demonstrando que bactérias que compartilham características morfológicas similares, podem representar isolados diferentes. Este método também demonstrou que órgãos vegetais, colmo e folha, compartilham de poucos isolados
Efeito antitumoral e antiangiogênico dos extratos bruto e supercríticoo de Bidens pilosa Linné e Casearia sylvestris Swartz
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-Graduação em FarmáciaO desenvolvimento de novas alternativas terapêuticas, como as que utilizam as plantas medicinais, tem despertado grande interesse no tratamento do câncer, pois as terapêuticas tradicionais não são capazes de regredir totalmente a evolução da doença e/ou apresentam elevada toxicidade. B. pilosa e C. sylvestris, plantas medicinais que possuem vários usos populares no Brasil e outros países americanos, têm sido indicadas para o tratamento de tumores. Neste estudo a extração supercrítica (ESC) foi o método de escolha, por seu bom fracionamento presentes na matriz vegetal. Assim sendo, o presente trabalho se propôs avaliar as atividades citotóxica, antiproliferativa, antitumoral, nucleásica, antiangiogênica e pró-apoptótica dos extratos bruto e supercrítico de B. pilosa e C. sylvestris em diferentes condições de extração utilizando modelos experimentais in vitro e in vivo. Para se atingir tal objetivo, foram realizados experimentos para avaliar primeiramente a atividade citotóxica (MTT) in vitro com extrato bruto (EB) (0-500 ?g/mL) e nos extratos na extração supercrítica (ESC) 250bar/40°C (0-100 ?g/mL), e a atividade antiproliferativa através do ensaio clonogênico (100 e 200 ?g/mL ) dos extratos de B. pilosa. Os resultados obtidos no MTT e ensaio clonogênico mostraram que os EB e ESC 250 bar/40°C de B. pilosa foram ineficazes em reduzir a viabilidade celular e antiproliferativa em células MCF-7 e T-24. A partir dos resultados obtidos com B. pilosa descritos acima, foram realizados os ensaios de viabilidade celular (MTT) em células MCF-7 (5, 10, 20, 40 e 80 ?g/mL) e T-24 (1; 2,5; 5; 7,7 e 10 ?g/mL) com as diversas condições de ESC de C. sylvestris. Já o EB de C. sylvestris foi realizado em células MCF-7, em concentrações de 62,5; 125; 250; 500 e 1000 ?g/mL e em T-24 nas concetrações de 10; 25; 50; 75 e 100 ?g/mL. Além disso, foi avaliado o efeito dos extratos (EtOH5% 300bar/40°C e EtOac5% 300bar/40°C) sobre o DNA plasmidial através da ativida nucleásica. A atividade antitumoral in vivo foi realizada em camundongos Balb/C inoculados com o TAE e tratados com EB de C. sylvestris e ESC (EtOH5% 300 bar/40°C e EtOac5% 300bar/40°C) de C. sylvestris nas concentrações de 0,1; 1 e 10 mg/kg e através da atividade antiangiogênica em ovos fertilizados de Gallus domesticus, através do ensaio da membrana corioalantóica (MCA), nas mesmas concentrações de 1, 5 e 10 mg/kg/dia. Também foi avaliada a capacidade pró-poptótica, através do ensaio de anexina V por citometria de fluxo em células TAE retiradas dos camundongos após o tratamento com os extratos supercríticos EtOH 5% 300bar/40°C de 0,1 mg/kg/dia, EtOac5% 300bar/40°C de 0,1mg/kg/dia e EtOac5% 300bar/40°C de 1 mg/kg/dia, que elevaram o percentual de células apoptóticas e necróticas de C. sylvestris. Os resultados demonstraram que os extratos supercríticos (EtOH5% 300bar/40°C e EtOac5% 300bar/40°C) de C. Sylvestris reduziram de maneira significativa a viabilidade de células MCF-7 e T-24. Em relação à avaliação da atividade nucleásica com o extrato supercrítico EtOH5% 300bar/40°C, se observou que houve dano direto ao DNA, sendo que o mesmo foi dose-dependente. Os ensaios in vivo demonstraram que os extratos supercríticos EtOH5% 300bar/40°C e EtOac5% 300bar/40°C apresentaram atividades antitumorais consideráveis. O tratamento com os extratos causaram importante inibição do crescimento tumoral nos camundongos, principalmente o extrato supercrítico EtOH5% 300bar/40°C (0,1 mg/kg/dia), causando também aumento do percentual médio de longevidade (PAL). O ensaio da anexina V revelou que a morte celular induzida pelos extratos supercríticos foi do tipo apoptose (EtOH 0,1 mg/kg/dia e EtOac 0,1 mg/kg/dia) e necrose (EtOac 1 mg/kg/dia). A atividade antiangiogênica dos EtOH5% 300bar/40°C e EtOAc5% 300bar/40°C (1, 5 e 10 mg/kg/dia) mostrou que os extratos foram capazes de reduzir de forma significativa o percentual de vasos sanguíneos em torno do embrião, sendo este efeito inversamente proporcional às concentrações.The development of new therapies, such as therapies using medicinal plants, has aroused great interest in cancer treatment, because the available therapies are not able to completely regress the disease progression and/or presents high toxicity. B. pilosa and C. sylvestris, medicinal plants that possess multiple popular uses in Brazil and other American countries, has been indicated for tumor treatment. In this study, the supercritical extraction (ESC) was the choice method for its superior performance in isolation of chemical compounds. Therefore, this study aimed to assess the cytotoxic, antiproliferative, antitumor, nucleasic, antiangiogenic and apoptotic activity of supercritical extract of B. pilosa and C. sylvestris at different extraction conditions using experimental models in vitro and in vivo. To achieve this goal, experiments were performed previously to evaluate the cytotoxic activity (MTT) in vitro with EB (0-500 µg/mL) and supercritical extract 250bar/40 °C (0-100 µg/mL), and antiproliferative activity via the clonogenic assay of B. pilosa extracts. The results obtained from MTT and clonogenic assay demonstrated that the B. pilosa EB and supercritical extract 250bar/40°C were ineffective in reducing cell viability and antiproliferative in MCF-7 cells and T-24. Considering the results obtained with B. pilosa described above, assays were performed in cell viability (MTT) in MCF-7 cells (5, 10, 20, 40 and 80 ?g/mL) and T-24 (1; 2.5; 5; 7.7 and 10 µg/ml) with ESC conditions with C. sylvestris. The EBC was performed on MCF-7 cells at concentrations of 62.5, 125, 250, 500 and 1000 µg/mL and T-24 in concetrations 10, 25, 50, 75 and 100 µg/ mL. Furthermore, the effect of extracts (EtOH5% 300bar/40°C and EtOac5% 300bar/40 °C) on plasmid DNA through the nuclease activity was also evaluated. The in vivo antitumor activity was performed in Balb/C mice inoculated with TAE treated with EBC and supercritical extract (EtOH5% 300bar/40°C and EtOac5% 300bar/40°C) of C. sylvestris at concentrations of 0.1, 1 and 10 mg/Kg and through the antiangiogenic activity of Gallus domesticus eggs fertilized by the chorioallantoic membrane essay (CAM) at the same concentrations of 1, 5 and 10 mg/kg/day. The pro-apoptotic ability was also evaluated by annexin V essay using flow cytometry in TAE cells taken from mice after treatment with the supercritical extract EtOH5% 300bar/40°C of 0.1 mg/kg/day, EtOac5% 300bar/40°C of 0.1 mg/ kg/day and EtOac 1mg/kg/day of 1 mg/kg/day that increased the apoptotic and necrotic cells percentage of C. sylvestris. The results demonstrated that the supercritical extract (EtOH5% 300bar/40°C and EtOac5% 300bar/40 °C) of C. Sylvestris significantly reduced the viability of MCF-7 and T-24 cells. Regarding the nuclease activity assessment with the supercritical extract EtOH5% 300bar/40°C, there was a direct dose-dependent damage on DNA. In vivo assays demonstrated that supercritical extract EtOH5% 300bar/40°C and EtOac5% 300bar/40°C showed considerable antitumor activity. The treatment with the extracts caused significant inhibition of tumor growth in mice, mainly the supercritical extract EtOH5% 300bar/40°C (0.1 mg/kg/day), also causing increase in the average percentage of longevity (PAL). The annexin V essay revealed that the induced cell death by extracts was apoptosis type (EtOH5% 300bar/40°C 0.1 mg/kg/day and EtOac5% 300bar/40°C 0.1 mg/kg/day) and also necrosis type (EtOac5% 300bar/40°C 1mg/kg/day). The antiangiogenic activity of the EtOH5% 300bar/40°C and EtOac5% 300bar/40°C (1, 5 and 10 mg/kg/day) demonstrated that the extracts were able to reduce significantly the percentage of blood vessels around the embryo being this effect inversely proportional to their concentrations
Avaliação da qualidade do leite produzido sob diferentes sistemas de produção no oeste de Santa Catarina
No full textDissertação (mestrado profissional) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Recursos Genéticos Vegetais (Mestrado Profissional), Florianópolis, 2013A atividade leiteira no Oeste de Santa Catarina tem sido, nos últimos anos, o principal meio de geração de renda para muitos agricultores familiares. Na região, há um grande número de produtores que adotam o sistema de produção a pasto associado ao uso de suplementos (concentrado e/ou volumoso) e um crescente número de propriedades de base ecológica, algumas já com certificação orgânica. Sendo assim, o objetivo do presente trabalho foi comparar a qualidade química, sanitária e microbiológica do leite proveniente da pecuária de base ecológica com a convencional na região Oeste de Santa Catarina. A caracterização do sistema de produção foi obtida a partir de visitas e entrevistas semi-estruturadas. Para a avaliação da composição química do leite foram realizadas 2 coletas, nas diferentes estações do ano, de 3 animais pré-selecionados de fenótipo (cruzamento Jersey x Holandês) e de estágio de lactação similares (3 a 6 meses) e para a qualidade sanitária e microbiológica dos tanques de resfriamento em cada Unidade de Produção Familiar (UPF) em estudo. Realizou-se também a identificação botânica das espécies forrageiras consumidas a partir da observação dos animais em pastoreio. Os sistemas diferiram na sua configuração produtiva, tendo as UPFs convencionais maior área total da propriedade, área de pastagens para espécies anuais (APA), número de animais em lactação e produção de leite e as de base ecológica maior área destinada para espécies perenes (APP). Nestas, observou-se pastagens mais diversificadas em todas as estações, especialmente no inverno e primavera. Enquanto Penisetum americanum e Sorghum sudanensis predominaram nas UPFs convencionais no verão, Avena sativa e Lolium multiflorum, foram as espécies usadas para a produção de leite nas outras estações do ano. Além disso, verificou-se correlação positiva (r2=0,74, pThe milk production activity in the West of Santa Catarina has been the main means to generate income for a lot of family farmers in the last years. In the region, there is a big number of producers who adopt the production system on pastures associated with the use of supplements (concentrate and/or bulky) and an increasing number of agro-ecologic farms, some of which already have organic certification. This way, this study aimed at comparing the chemical, sanitary and microbiologic quality of milk coming from farms with ecological basis and of milk coming from conventional farms, in the west region of Santa Catarina. The characterization of the production system was obtained from visits and semi-structured interviews. To evaluate the milk chemical composition, two samplings were done, in different seasons of the year, from three pre-selected animals of phenotype (crossbreeding Jersey x Holstein) and of similar lactation stages (three to six months) and for the sanitary and microbiological quality of the cooling tanks in each Family Production Unit (FPU) under study. The identification of forages species consumed was also accomplished through observation of animals on pastures. The systems differentiated in their productive configuration, on one hand the conventional FPUs were characterized by having a bigger total area of the farm, pasture areas for annual species (APA), a higher number of animals in lactation stages and milk production; on the other hand the area of perennial pasture (PPA) was bigger on agro-ecological farms, which presented more diversified pastures in different seasons of the year, especially in winter and spring. While Penisetum americanum and Sorghum sudanensis were predominant in the summer in the conventional FPUs, Avena sativa and Lolium multiflorum were the species used for milk production in the other seasons of the year. Besides this, a positive correlation was verified (r2=0,74, p<0,05) between the percentage of PPA and the average number of consumed forage species. Regarding the differences of botanic composition and food handling among the treatments, the nutritional value of agro-ecological milk did not differ from the conventional one, except for the higher fat levels in the winter. The protein level, lactose and non fat solids differed only among the seasons of the year. Besides, the chemical composition of the milk was in accordance with the parameters allowed by IN62; except for the levels of non fat solids (winter) and lactose (fall) in all the treatments. In the same way, the influence of the production system on the sanitary and microbiological quality of the milk was not verified. However, values of CCS and CBT above the ones allowed by the IN62 were found in several FPUs. In the fall and spring, 50% and 58.33% of the FPUs, respectively, showed a CBT value above the one allowed by IN62. The same was observed for CCS, with 41.67% (winter) and 33.33% (summer) of the FPUs, not in accordance with the legislation requirements. These results suggest the necessity of improvements in the hygiene and milking handling in the FPUs under study. The multi-varied analysis of data through the application of principal component analysis (PCA) of all parameters studied showed that the production system used in the agro-ecological FPUs was different from the conventional one; the higher percentage of APA and PPA was the responsible factor for the distinction from FPUs of agro-ecological basis and conventional ones. All together, the results found showed that the milk quality produced by family farmers in the West of Santa Catarina was not affected by the production system, although these systems were clearly differentiated in their productive configuration
Lithium fluoride injection layers can form quasi-Ohmic contacts for both holes and electrons
No full textThin LiF interlayers are typically used in organic light-emitting diodes to enhance the electron injection. Here, we show that the effective work function of a contact with a LiF interlayer can be either raised or lowered depending on the history of the applied bias. Formation of quasi-Ohmic contacts for both electrons and holes is demonstrated by electroluminescence from symmetric LiF/polymer/LiF diodes in both bias polarities. The origin of the dynamic switching is charging of electrically induced Frenkel defects. The current density-electroluminescence-voltage characteristics can qualitatively be explained. The interpretation is corroborated by unipolar memristive switching and by bias dependent reflection measurements. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License
