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91.
Andreza Conti‐Patara DVM MSc PhD Juliana de Araújo Caldeira DVM Ewaldo de Mattos‐Junior DVM MS Haley da Silva de Carvalho DVM MSc Adriane Reinoldes DVM Bruno Gregnanin Pedron DVM Marcelo Patara MD Mariana Semião Francisco Talib DVM Marcelo Faustino DVM Clair Motos de Oliveira DVM MSc PhD Silvia Renata Gaido Cortopassi DVM MSc PhD 《Journal of Veterinary Emergency and Critical Care》2012,22(4):409-418
92.
Moon CR Mattos LS Foster BK Zeltzer G Ko W Manoharan HC 《Science (New York, N.Y.)》2008,319(5864):782-787
Quantum phase is not directly observable and is usually determined by interferometric methods. We present a method to map complete electron wave functions, including internal quantum phase information, from measured single-state probability densities. We harness the mathematical discovery of drum-like manifolds bearing different shapes but identical resonances, and construct quantum isospectral nanostructures with matching electronic structure but divergent physical structure. Quantum measurement (scanning tunneling microscopy) of these "quantum drums"-degenerate two-dimensional electron states on the copper(111) surface confined by individually positioned carbon monoxide molecules-reveals that isospectrality provides an extra topological degree of freedom enabling robust quantum state transplantation and phase extraction. 相似文献
93.
94.
Franco AC Herzog B Hübner C De Mattos EA Scarano FR Ball E Lüttge U 《Tree physiology》1999,19(10):635-644
Crassulacean acid metabolism (CAM) plants are dependent on the organic acids that accumulate overnight in the vacuoles as a source of CO(2) during the daylight deacidification period, when stomata are closed and high irradiances generally prevail. We performed an integrative analysis of diurnal changes in gas exchange, chlorophyll fluorescence parameters and organic acid decarboxylation to understand the adjustments in photochemical and non-photochemical processes during the different CAM phases in Clusia hilariana Schlecht., a dominant tree species in the sandy coastal plains of southeastern Brazil. A linear relationship was obtained between the quantum yields of photochemical and non-photochemical quenching, irrespective of the CAM phase and prevailing irradiance. Degradation of malic and citric acids during the midday stomatal closure period could lead to potential CO(2) fixation rates of 23 &mgr;mol m(-2) s(-1), whereas CO(2) losses, measured as CO(2) evolution, corresponded to about 3% of this value. Thus, decarboxylation of malate and citrate provided high internal CO(2) concentrations during phase III of CAM, even though the stomata were closed, allowing optimal utilization of light energy, as indicated by the non-saturating electron transport rates (ETR) in the light response curves, with highest rates of ETR occurring at midday in the diurnal curves. At the transition from phase III to IV of CAM, depletion of internal CO(2) sources and low stomatal conductances, which restricted the supply of exogenous CO(2), reduced the demand for photochemical energy to drive carbon assimilation. This was compensated by increases in thermal energy dissipation as indicated by higher rates of non-photochemical quenching, while high irradiances still prevailed. Shifts in the CAM phases and changes in protective thermal dissipation potential allowed C. hilariana to match changes in PPFD patterns for leaves of different orientations. Evidence that most of the decline in photochemical efficiency was probably related to the fast-relaxing component of non-photochemical quenching is provided by the high values of the quantum yield of photosystem II after 20 min of relaxation in darkness, and an almost complete recovery after sunset. These adjustments in photosynthetic machinery minimized the danger of photo-inhibition in C. hilariana, which is commonly found in fully exposed habitats. 相似文献
95.
96.
Recombinant cDNA probe from bluetongue virus genome segment 10 for identification of bluetongue virus 总被引:2,自引:0,他引:2
C A de Mattos C C de Mattos B I Osburn 《Journal of veterinary diagnostic investigation》1989,1(3):237-241
Genome segment 10 of bluetongue virus (BTV) serotype 11 UC8 strain was cloned and subsequently hybridized to viral double-stranded RNA extracted from 90 field isolates of BTV serotypes 10, 11, 13, and 17; the prototype strains of BTV 2, 10, 11, 13, and 17; the prototype strain epizootic hemorrhagic disease virus (EHDV) serotype 1; and 4 field isolates of EHDV serotype 2. The 90 field isolates were obtained from different counties in California, Louisiana, and Idaho during the years 1979, 1980, and 1981. The cloned genetic probe hybridized with all the BTV samples tested, showing different degrees of cross-hybridization at the stringency conditions used in this study. This indicated that BTV genome segment 10 has conserved nucleotide sequences among the BTV serotypes 2, 10, 11, 13, and 17. No cross-hybridization signals were detected between the cloned genome segment 10 of BTV 11 UC8 strain and the prototype strain of EHDV serotype 1 and the field isolates of serotype 2. This probe recognized a wide variety of BTV isolates. 相似文献
97.
Geisa Lima Mesquita Francisco Andr�� Ossamu Tanaka Heitor Cantarella Dirceu Mattos Jr 《Water, air, and soil pollution》2011,219(1-4):143-156
Fluoride (F) is an air pollutant that causes phytotoxicity. Besides the importance of this, losses of agricultural crops in the vicinity of F polluting industries in Brazil have been recently reported. Injuries caused to plant leaf cell structures by excess F are not well characterized. However, this may contribute to understanding the ways in which plant physiological and biochemical processes are altered. A study evaluated the effects of the atmospheric F on leaf characteristics and growth of young trees of sweet orange and coffee exposed to low (0.04 mol L?1) or high (0.16 mol L?1) doses of HF nebulized in closed chamber for 28 days plus a control treatment not exposed. Gladiolus and ryegrass were used as bioindicators in the experiment to monitor F exposure levels. Fluoride concentration and dry mass of leaves were evaluated. Leaf anatomy was observed under light and electron microscopy. High F concentrations (~180 mg kg?1) were found in leaves of plants exposed at the highest dose of HF. Visual symptoms of F toxicity in leaves of citrus and coffee were observed. Analyses of plant tissue provided evidence that F caused degeneration of cell wall and cytoplasm and disorganization of bundle sheath, which were more evident in Gladiolus and coffee. Minor changes were observed for sweet orange and ryegrass. Increase on individual stomatal area was also marked for the Gladiolus and coffee, and which were characterized by occurrence of opened ostioles. The increased F absorption by leaves and changes at the structural and ultrastructural level of leaf tissues correlated with reduced plant growth. 相似文献
98.
Helio Garcia Leite Mayra Luiza Marques da Silva Daniel Henrique Breda Binoti Leonardo Fardin Fausto Hissashi Takizawa 《European Journal of Forest Research》2011,130(2):263-269
The objective of this study was to obtain neural networks that would precisely estimate inside-bark diameter (d ib ) and heartwood diameter (d h ) and compare to the results obtained by the Taper models. The databank was formed so as to eliminate inconsistent and biased data, and stratified: minimum d ib of 4, 6 and 8 cm and minimum d h of 10, 15 and 20 cm. The adjusted Taper model used was the Kozak model. For the fitting of artificial neural networks (ANN), tests were performed to identify the independent variables and the database scope level, i.e., the following input variables were tested: diameter at breast height (dbh), total height (H), height at diameter d ib or d h (h) and outside-bark diameter at h (d ob ), bark thickness at 1.3 m and project, and the scope at database level or project level. The estimates obtained by the neural networks and Kozak model were evaluated by residual graphs in function of the respective diameter observed and graph of the observed versus estimated values. ANN were found to be more efficient in estimating inside-bark and heartwood diameters for Tectona grandis trees than the Kozak model. The variables that must be used to fit the networks are dbh, H, h and d ob . Stratification by project results in precision gain, with precision being higher for wider commercial diameters. Thus, linear-type artificial neural networks can be efficient in describing the taper of Tectona grandis trees. 相似文献
99.
Clarisse G Cardoso Danilo RC Marques Thiago HM da Silva Ewaldo de Mattos‐Junior 《Veterinary anaesthesia and analgesia》2014,41(6):636-643
ObjectiveTo evaluate the cardiorespiratory, sedative and antinociceptive effects of dexmedetomidine alone or in combination with methadone, morphine or tramadol in dogs.Study designExperimental, blinded, randomized, crossover study.AnimalsSix mixed breed dogs (two males and four females) weighing 10 ± 4 kg.MethodsThe animals were randomly divided into four treatments: D (10 μg kg?1 of dexmedetomidine), DM (dexmedetomidine 10 μg kg?1 and methadone 0.5 mg kg?1); DMO (dexmedetomidine 10 μg kg?1 and morphine 0.5 mg kg?1), and DT (dexmedetomidine 10 μg kg?1 and tramadol 2 mg kg?1). The combinations were administered intramuscularly in all treatments. The variables evaluated were heart rate (HR), respiratory rate (fR), rectal temperature (RT), systolic arterial pressure (SAP), sedation scale and pedal withdrawal reflex. These variables were measured at T0 (immediately before the administration of the protocol) and every 15 minutes thereafter until T105.ResultsA decrease in HR and fR occurred in all the treatments compared with T0, but no significant difference was observed between the treatments. The RT decreased from T45 onward in all the treatments. The SAP did not show a difference between the treatments, but in the DT treatment, the SAP was lower at T30 and T45 compared with T0. The D treatment had lower scores of sedation at T15 to T75 compared with the other treatments, and the DMO and DM treatments showed higher scores at T60 and T75 compared with DT.Conclusions and clinical relevanceThe treatments with morphine and methadone added to the dexmedetomidine showed higher sedation scores than the control treatment and the treatment with tramadol added to the dexmedetomidine showed no relevant differences in any of the variables evaluated in the study. 相似文献
100.
Marcelo Bettega Lucas Wagner Gortz Luiza Fernanda Schier Aniele Cristine Ott Clemente Osvaldo Malafaia Claudia do Carmo Consuelo Ota 《农业科学与技术》2013,(8):659-665
Purpose: to evaluate the in vitro influence of Copaiferalangsdorffii essential oil on the antinecrotic activity in macrophages, and on the antiapoptotic activity in macrophages and lymphocytes of Swiss mice. Methods: lymphocytes and macrophages were obtained from ten 60-day-old male mice weighing 42-45 g, and then cultured in 24-well plates. Cells were treated with concentrations of 2%, 5%, 10% and 20% of oil from Copaiferalangsdorffii before or after induction of apoptosis with ultraviolet light. We used positive and negative controls. Hoechst staining was performed, and then images of cells under fluorescence microscope were captured and digitalized. We used Image J_1.46o to quantify the fluorescence intensity/brightness of condensation of the chromatin ofapoptotic cells. We used one-way ANOVA with Bonferroni's and Tukey's multiple comparison tests. Results are expressed as the means of relative densities after adjustment and 95% confidence intervals; P 〈 0.05 was considered statistically significant. Results: oil from Copaiferalangsdorffii at different concentrations has decreased necrosis and apoptosis of both lymphocytes and macrophages from mice, when compared to C+ (all P 〈 0.05). Discussion: Copaiferalangsdorffii is typically Brazilian and found in the Amazon region, with anti-inflammatory, antioxidant and antineoplastic effects due to its oil compounds, such as xyloglucans and kaurenoic acid. Its potential therapeutical usage was demonstrated in a national study. The present study showed that its oil has significant in vitro antiapoptotic and antinecrotic activity and it should be tested experimentally in vivo. 相似文献