54 research outputs found
Antimicrobial activity of phosphites against different potato pathogens
Phosphites have low-toxicity on the environment and show high efficacy in controlling oomycete diseases in plants, both by a direct and an indirect mechanism. We have shown that they are also effective in reducing disease symptoms produced byPhytophthora infestans, Fusarium solaniandRhizoctonia solaniwhen applied to potato seed tubers. To gain better insight into the direct mode of action of phosphites on different potato pathogens, and to ascertain chemical determinants in their direct antimicrobial activity, four potato pathogens were assayed with respect to sensitivity toward calcium, potassium and copper phosphites (CaPhi, KPhi and CuPhi, respectively). The influence of acidification and ionic strength changes after Phi addition on the antimicrobial activity, and the fungicidal or fungistatic activity, were evaluated. Results showed that phosphites were able to inhibit growth of all pathogens.Phytophthora infestanswas the most inhibited pathogen by all phosphites, followed byStreptomyces scabies, whileRhizoctonia solaniandFusarium solaniwere less inhibited. CuPhi had the highest antimicrobial activity against the four pathogens analysed, and CaPhi and KPhi showed similar antimicrobial activities. Inhibitions by CuPhi and CaPhi could be partially explained by acidification of the media. However, results obtained with KPhi demonstrated that the phosphite anion has antimicrobial activity itself. The increase in ionic strength after Phi addition was not important in the antimicrobial activity of Phi. The activity of phosphites on germination ofF. solanispores showed to be fungistatic rather than fungicidal.Phosphite besitzen eine geringe Umwelttoxizität sowie eine gute direkte und indirekte Wirkung gegenüber Oomyceten- Pathogenen von Pflanzen. Wir zeigen hier, dass sie ebenfalls die durchPhytophthora infestans,Fusarium solaniandRhizoctonia solaniverursachten Symptome an Kartoffeln nach einer Knollenbehandlung vermindern. Vier Kartoffelpathogene wurden mit dem Ziel untersucht, die direkte Wirkungsweise von Calcium-, Kalium- und Kupfer-Phosphiten (CaPhi, KPhi und CuPhi) auf die Erreger sowie die chemischen Determinanten ihrer direkten antimikrobiellen Aktivität zu ermitteln. Weiterhin wurde die Wirkung von Azidifizierung und Ionenstärke nach Zugabe von Phosphiten auf antimikrobielle, fungizide und fungistatische Aktivität untersucht. Die Phosphite beeinträchtigten das Wachstum aller untersuchten Erreger.Phytophthora infestanswurde durch alle verwendeten Phosphite am stärksten inhibiert, gefolgt vonStreptomyces scabies, während die Wirkung aufRhizoctonia solaniundFusarium solanigeringer war. CuPhi besaß die höchste antimikrobielle Aktivität gegenüber den vier untersuchten Pathogene, gefolgt von den ähnlich wirksamen CaPhi und KPhi. Die Wirkung von CuPhi und CaPhi kann zum Teil durch die Ansäuerung der verwendeten Medien erklärt werden. Die mit KPhi erhaltenen Ergebnisse zeigen dagegen, dass das Phosphit-Anion selbst antimikrobiell wirksam ist. Die Zunahme der Ionenstärke nach Phosphit-Applikation war nicht für die antimikrobielle Wirkung verantwortlich. Die Beeinträchtigung der Sporenkeimung vonF. solanizeigte, dass die Wirkung der Phosphite eher fungistatisch als fungizid ist
Effect of foliar applications of phosphite on post-harvest potato tubers
The utilization of phosphites (Phi) could be considered as another strategy to be included in integrated disease management programmes to reduce the intensive use of fungicides and production costs. The aim of the present work was to analyze whether the beneficial effects of phosphite treatment previously observed in potato plants grown under greenhouse conditions, were reflected after harvest of field grown potatoes, both in disease protection and in yield. In addition, biochemical compounds possibly involved in induced defence responses by Phi, like phytoalexins, pathogenesis related proteins and oxidative stress enzymes were measured. Foliar applications of KPhi to field grown crops resulted in post-harvest tubers with a reduced susceptibility to Phytophthora infestans, Fusarium solani and Erwinia carotovora infections, suggesting that this compound induced a systemic defence response. An increase in phytoalexin content in P. infestans inoculated tubers obtained from Phi-treated plants suggests their participation in the defence response. Chitinase content increased 72h after wounding or inoculation with P. infestans in tubers from KPhi-treated plants compared to wounded or infected tubers from non-treated plants. Contrary to this, the isoforms of β-1,3-glucanases analyzed did not increase in the tubers of Phi-treated plants. The increment in peroxidase and polyphenol oxidase activities indicated that these enzymes could be part of the Phi defence mechanism. No negative effects were observed in potato yield at harvest, measured as total tuber weight and dry matter, after foliar KPhi treatment. This suggests that the energetic cost involved in the defence response activation would not be detrimental to plant growth
End-Stage Renal Disease in Familial Amyloidosis ATTR Val30Met: A
Transplant Proc. 2003 May;35(3):1116-20.
End-stage renal disease in familial amyloidosis ATTR Val30Met: a definitive indication to combined liver-kidney transplantation.
Lobato L, Ventura A, Beirão I, Miranda HP, Seca R, Henriques AC, Teixeira M, Sarmento AM, Pereira MC.
Department of Nephrology, and Liver Transplantation Program, Hospital Geral de Santo António, Largo Professor Abel Salazar, 4050, Porto, Portugal. [email protected]
PMID: 12947881 [PubMed - indexed for MEDLINE
Análisis semicuantitativo del calcio y fósforo en los tejidos calcificados de la mandíbula
El objetivo de nuestra investigación es realizar un estudio microanalítico semicuantitativo del
calcio y el fósforo en los tejidos calcificados de la mandíbula. Dentro de este estudio se pretende
calcular el valor de la ratio Ca/P por métodos semicuantitativos y compararlo con los valores
estequiométricos de la ratio Ca/P de la hidroxiapatita referidos en la literatura; conocer los valores
de la ratio Ca/P obtenidos para el tejido condroide, el hueso lamelar, el hueso fibrorreticular y el
cartílago calcificado en las muestras fetales, por una parte, y adultas, por otra; y si existen o no
diferencias significativas en la proporción Ca/P obtenidos para feto y adulto. El análisis morfológico
de los tejidos calcificados fue realizado por medio de Microrradiografía Electrónica de Barrido
(MEB) por electrones retrodispersados (Backscattering), y los resultados permiten afirmar que la
ratio obtenida por análisis semicuantitativo mediante dispersión de rayos X de los tejidos calcificados
(condroide, hueso lamelar y fibrorreticular) se encuentra más próxima a 1, y que no existen diferencias
significativas entre las muestras fetales y de adulto en los tejidos analizados
Análisis semicuantitativo del calcio y fósforo en el esmalte y la dentina
Existe una serie de características comunes asociadas al proceso biológico de formación de los
tejidos calcificados a pesar de que los productos finales sean estructuralmente distintos. La presente
investigación tiene como propósito determinar si la ratio Ca/P ratio es la misma para los tejidos
calcificados dentales tanto del feto como del adulto y si dicha ratio es diferente al valor de la ratio
Ca/P de la hidroxiapatita pura calculada por estequiometría. Se escogió como material de observación
el esmalte y la dentina, en muestras de fetos humanos y en un total de 30 ratas adultas de
raza Wistar y 20 dientes humanos sanos. Las observaciones se llevaron a cabo por medio de
Microscopia Electrónica de Barrido y Microanálisis por separación de energía de rayos X. Los
valores totales de la ratio Ca/P para el esmalte oscilaron en un intervalo de 0,9 y 1,2, con una media
que se encuentra entre 1,07 y 1,08. Los valores totales de la ratio Ca/P para la dentina oscilan entre
1,03 y 1,12 y la media entre 1,07 y 1,075. No se encontraron diferencias estadísticamente significativas
entre esmalte fetal y adulto ni entre la dentina fetal y adulta. Aún no pudiendo definir la
existencia de precursores específicos en los tejidos calcificados del diente (esmalte y dentina),
nuestros resultados sugieren que no toda la cristalización de estos tejidos corre a cargo de la
hidroxiapatita sino que deben haber otros compuestos que expliquen la disminución del valor de la
ratio Ca/P en las muestras estudiadas
Human-robot collaboration (HRC) with vision inspection for PCB assembly
Flexibility and speed in the development of new industrial machines are essential factors for the success of capital goods industries. When assembling a printed circuit board (PCB), since all the components are surface-mounted devices (SMD), the whole process is automatic. However, in many PCBs, it is necessary to place components that are not SMDs, called pin through-hole components (PTH), having to be inserted manually, which leads to delays in the production line. This work proposes and validates a prototype work cell based on a collaborative robot and vision systems whose objective is to insert these components in a completely autonomous or semi-autonomous way. Different tests were made to validate this work cell, showing the correct implementation and the possibility of replacing the human worker on this PCB assembly task.ERDF - European Regional Development Fund(45070
Melhoramento ótico de células solares tandem com base em silício cristalino
CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMO: A estratégia mais promissora para reduzir o custo da eletricidade fotovoltaica é o aumento da eficiência dos sistemas. As células de silício cristalino estão cada vez mais próximas do seu limite teórico de eficiência, sendo por isso progressivamente mais difícil aumentar a sua de eficiência. As células solares tandem com base em silício cristalino são um dos caminhos mais promissores para atingir uma eficiência de conversão para além dos 30% com um custo competitivo. Neste artigo é apresentada uma proposta de célula tandem com base em silício cristalino de com três terminais em que as subcélulas são ligadas em paralelo, sendo também propostas algumas estratégias para melhorar as propriedades óticas deste dispositivo. São apresentados os resultados do desenvolvimento de um método de melhoramento do desempenho ótico do silício cristalino, baseado em gravação química assistida por metal, e de simulações numéricas de dispositivos.ABSTRACT: The most promising strategy to reduce the cost of photovoltaic electricity is to increase the systems’ efficiency. Crystalline silicon cells are getting closer to their theoretical efficiency limit, which is why it is progressively more difficult to increase their efficiency. Crystalline silicon-based tandem solar cells are one of the most promising ways to achieve conversion efficiency beyond 30% at a competitive cost. This article presents a proposal for a tandem cell based on crystalline silicon with three terminals in which the subcells are connected in parallel, and some strategies to improve the optical properties of this device are proposed. The results of the development of a method to improve the optical performance of crystalline silicon, based on metal-assisted chemical etching and numerical device simulations’ results are presented.info:eu-repo/semantics/publishedVersio
Topo-Iberia Project: CGPS crustal velocity field in the Iberian Peninsula and Morocco
A new continuous GPS network was installed under the umbrella of a research project called 'Geociencias en Iberia: Estudios integrados de topografı´a y evolución 4D (Topo-Iberia)', to improve understanding of kinematic behavior of the Iberian Peninsula region. Here we present a velocity field based on the analysis of the 4 years of data from 25 stations constituting the network, which were analyzed by three different analysis groups contributing to the project. Different geodetic software packages (GIPSY-OASIS, Bernese and GAMIT) as well as different approaches were used to estimate rates of present day crustal deformation in the Iberian Peninsula and Morocco. In order to ensure the consistency of the velocity fields determined by the three groups, the velocities obtained by each analysis center were transformed into a common Eurasia Reference Frame. After that, the strain rate field was calculated. The results put in evidence more prominent residual motions in Morocco and southernmost part of the Iberian Peninsula. In particular, the dilatation and shear strain rates reach their maximum values in the Central Betics and northern Alboran Sea. A small region of high shear strain rate is observed in the east-central part of the peninsula and another deformation focus is located around the Strait of Gibraltar and the Gulf of Cadiz
A surveillance of enteropathogens in piglets from birth to seven days of age in Brazil
Genotyping and antimicrobial susceptibility of Clostridium perfringens isolated from Tinamidae, Cracidae and Ramphastidae species in Brazil
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