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91.
92.
Domenico Caivano Francesco Birettoni Alessandro Fruganti Mark Rishniw Patrizia Knafelz N. Sydney Moïse Francesco Porciello 《Journal of Veterinary Cardiology》2012,14(3):431-444
ObjectivesInterventional cardiac procedures are traditionally performed using fluoroscopy, or, more recently, transesophageal echocardiography (TEE). Neither modality is widely available to practicing cardiologists worldwide. We examined whether balloon valvuloplasty of pulmonic stenosis (PS) and transarterial occlusion of patent ductus arteriosus (PDA) in dogs could be performed safely with transthoracic echocardiography (TTE).AnimalsA prospective consecutive case series of 26 client-owned dogs with PS (n = 10) and PDA (n = 16).MethodsThe cardiovascular procedures were performed using TTE. Each dog was positioned on a standard echocardiography table in right lateral recumbency (dogs with PS) or left lateral recumbency (dogs with PDA). Guide wires, balloon catheters, Amplatz® Canine Ductal Occluder (ACDO) delivery sheaths, and ACDO were imaged by standard echocardiographic views optimized to allow visualization of the defects and devices.ResultsProcedures were performed successfully without major complications in 20 dogs. In 2 dogs (German shepherds) with Type III PDA, ACDO placement was unsuccessful; 2 other German Shepherds were excluded from the procedure because their ductal diameters, measured echocardiographically, exceeded the limits of the maximal ACDO size. Two dogs weighing ≤3.5 kg had suboptimal echocardiographic visualization of the PDA and were considered too small for safe ACDO deployment. All intravascular devices at the level of the heart and great vessels appeared hyperechoic on TTE image and could be clearly monitored and guided in real-time.ConclusionsWe have demonstrated that TTE monitoring can guide each step of pulmonic balloon valvuloplasty and PDA occlusion without fluoroscopy. 相似文献
93.
Gabriela Cristina Rabello Casagrande Cláudia dos Reis Rafael Arruda Ricardo Lopes Tortorela de Andrade Leandro Dênis Battirola 《Water, air, and soil pollution》2018,229(5):166
Aquatic macrophytes play a key role in nutrient cycling and in the dynamics of aquatic ecosystems. Many species have been evaluated in terms of their potential in phytoremediation processes in environments contaminated by metals. Considering this kind of application, we evaluated the potential for the bioaccumulation and biosorption of mercury by Salvinia biloba as a function of (i) different concentrations of mercury ions in the solution, (ii) the exposure time of live plants and dry biomass to the contaminant, and (iii) different pH’s, besides (iv) analyzing the effects of this metal on morphological and anatomical parameters. Bioaccumulation was evaluated by subjecting live plants to treatments with concentrations of 0.05, 0.1, and 0.2 μg.mL?1 of mercury in the solution and the control (0 μg.mL?1), at intervals of 3 days (0, 3, 6, 9, 12, and 15 days) at pH values of 5.5, 6.0, and 6.5. For biosorption, we used the dry biomass applying the same design, only changing the time intervals (0, 4, 8, 12, and 24 h). The bioaccumulated and biosorbed mercury was determined by atomic absorption spectroscopy. High values of mercury were bioaccumulated and biosorbed, and accordingly, as the concentration of mercury ions increases in the solution, the higher the value accumulated by both living plant and dry biomass. The time of exposure and the different pH values presented variation when associated with different concentrations in the bioaccumulation of mercury. Finally, few symptoms of toxicity in living plants were observed, evidencing the resistance of S. biloba to mercury and its potential use as a phytoremediation in water bodies contaminated by this metal. 相似文献
94.
Gut complex carbohydrates and intestinal microflora in broiler chickens fed with oregano (Origanum vulgare L.) aqueous extract and vitamin E 下载免费PDF全文
P. Scocco C. Forte M. P. Franciosini F. Mercati P. Casagrande‐Proietti C. Dall'Aglio G. Acuti F. M. Tardella M. Trabalza‐Marinucci 《Journal of animal physiology and animal nutrition》2017,101(4):676-684
One hundred and seventy one‐day‐old female broiler chicks were randomly divided into three groups fed with different dietary treatments: basal control diet (C); C supplemented (2 g/kg) with an oregano aqueous extract (O); C supplemented (150 mg/kg) with vitamin E (E). Growth performance was evaluated at 21 (T1) and 42 days (T2). On the same days, morphological, histochemical and microbiological analyses were performed. The O group showed the highest (p < 0.01) body weight at T1, while no differences were observed at T2. Light microscopic observation and conventional histochemistry showed no differences with regard to the two sampling times, whereas significant differences emerged among the treatments. The O treatment generally enhanced goblet cell reactivity more than both the C and E treatments. Coliform count was lower in the ileum tract of the O group at both T1 and T2 (p < 0.05) and increased with age in all groups. Escherichia coli showed the lowest values in the caecum of the O group (p < 0.001) at both sampling times. Enterococci, lactobacilli and staphylococci populations showed no differences among the different experimental groups in the caecum. In the ileum, the O group did not exhibit the sharp decline (p < 0.001) in the lactic acid bacteria population observed in the other two experimental groups. In conclusion, oregano aqueous extract supplementation seemed to elicit the best response among treatments, enabling better growth performance, enhancing both the quantity and quality of glycoconjugates involved in indirect defence actions and significantly reducing both the coliform and E. coli counts. 相似文献
95.
Cindy Silva Moreira José Carlos Casagrande Luís Reynaldo Ferracciú Alleoni Otávio Antônio de Camargo Ronaldo Severiano Berton 《Journal of Soils and Sediments》2008,8(6):442-451
Background, aim, and scope The retention of potentially toxic metals in highly weathered soils can follow different pathways that variably affect their
mobility and availability in the soil–water–plant system. This study aimed to evaluate the effects of pH, nature of electrolyte,
and ionic strength of the solution on nickel (Ni) adsorption by two acric Oxisols and a less weathered Alfisol.
Materials and methods The effect of pH on Ni adsorption was evaluated in surface and subsurface samples from a clayey textured Anionic ‘Rhodic’
Acrudox (RA), a sandy-clayey textured Anionic ‘Xantic’ Acrudox (XA), and a heavy clayey textured Rhodic Kandiudalf (RK). All
soil samples were equilibrated with the same concentration of Ni solution (5.0 mg L−1) and two electrolyte solutions (CaCl2 or NaCl) with different ionic strengths (IS) (1.0, 0.1 and 0.01 mol L−1). The pH of each sample set varied from 3 to 10 in order to obtain sorption envelopes.
Results and discussion Ni adsorption increased as the pH increased, reaching its maximum of nearly pH 6. The adsorption was highest in Alfisol, followed
by RA and XA. Competition between Ni2+ and Ca2+ was higher than that between Ni2+ and Na+ in all soil samples, as shown by the higher percentage of Ni adsorption at pH 5. At pH values below the intersection point
of the three ionic strength curves (zero point of salt effect), Ni adsorption was generally higher in the more concentrated
solution (highest IS), probably due to the neutralization of positive charges of soil colloids by Cl− ions and consequent adsorption of Ni2+. Above this point, Ni adsorption was higher in the more diluted solution (lowest ionic strength), due to the higher negative
potential at the colloid surfaces and the lower ionic competition for exchange sites in soil colloids.
Conclusions The effect of ionic strength was lower in the Oxisols than in the Alfisol. The main mechanism that controlled Ni adsorption
in the soils was the ionic exchange, since the adsorption of ionic species varied according to the variation of pH values.
The ionic competition revealed the importance of electrolyte composition and ionic strength on Ni adsorption in soils from
the humid tropics.
Recommendations and perspectives The presence of NaCl or CaCl2 in different ionic strengths affects the availability of heavy metals in contaminated soils. Therefore, the study of heavy
metal dynamics in highly weathered soils must consider this behavior, especially in soils with large amounts of acric components. 相似文献
96.
Diurnal and seasonal variations in leaf hydraulic conductance in evergreen and deciduous trees 总被引:1,自引:0,他引:1
We studied changes in the hydraulic conductance of leaves (K(leaf)) between dawn and dusk during the growth period (July) and at midday at the beginning of autumn in four tree species. The main objectives of the study were to check the extent of diurnal and seasonal changes in K(leaf) and the relationships between K(leaf), irradiance and leaf gas exchange. Two evergreen (Aleurites moluccana and Persea americana) and two deciduous trees (Platanus orientalis and Quercus rubra) were studied. Leaf hydraulic conductance was measured every 2 h between 0700 and 1900 h in July and compared with values measured between 0900 and 1300 h in October. Other variables measured were photosynthetically active radiation (PAR), leaf conductance to water vapor (gL) and water potential (psiL). In July, K(leaf) varied by up to 75% in Pe. americana on a diurnal basis and by at least 44% in Q. rubra. The diurnal time course of K(leaf) showed a distinct increase between dawn and late morning (1100 h) and a subsequent decrease in the evening in A. moluccana and Pl. orientalis, whereas in the other two species, K(leaf) was highest just after dawn and lowest in the evening. In October, K(leaf) of all the species studied was lower than in July, with differences of 20 to 28% for A. moluccana and Pl. orientalis and of 66 to over 70% in Pe. americana and Q. rubra, respectively. Significant correlations were found between PAR and K(leaf) (in all species) as well as between gL and K(leaf) (in three out of four species). Leaf habit (evergreen or deciduous) did not influence absolute values of K(leaf) or its diurnal variation. 相似文献
97.
The essential oils obtained from fifteen relevant and commonly used plants belonging to Cruciferae, Lamiaceae, Lauraceae, Apiaceae, and Zingiberaceae were screened using an in vitro model of peroxynitrite-induced tyrosine nitration. Almost complete inhibition of 3-nitrotyrosine formation (91% at 300 microg/ml) was achieved only with the essential oil obtained from the leaves of Laurus nobilis. 1,8-Cineol, accounting for a 50% of this essential oil, which resulted as inactive in this model, thus evidencing a major role for the minor volatile compounds present in the leaves. 相似文献
98.
Thomas Gschwantner Adrian Lanz Claude Vidal Michal Bosela Lucio Di Cosmo Jonas Fridman Patrizia Gasparini Andrius Kuliešis Stein Tomter Klemens Schadauer 《Annals of Forest Science》2016,73(4):807-821
Key message
The increment estimation methods of European NFIs were explored by means of 12 essential NFI features. The results indicate various differences among NFIs within the commonly acknowledged methodological frame. The perspectives for harmonisation at the European level are promising.Context
The estimation of increment is implemented differently in European National Forest Inventories (NFIs) due to different historical origins of NFIs and sampling designs and field assessments accommodated to country-specific conditions. The aspired harmonisation of increment estimation requires a comparison and an analysis of NFI methods.Aims
The objective was to investigate the differences in volume increment estimation methods used in European NFIs. The conducted work shall set a basis for harmonisation at the European level which is needed to improve information on forest resources for various strategic processes.Methods
A comprehensive enquiry was conducted during Cost Action FP1001 to explore the methods of increment estimation of 29 European NFIs. The enquiry built upon the preceding Cost Action E43 and was complemented by an analysis of literature to demonstrate the methodological backgrounds.Results
The comparison of methods revealed differences concerning the NFI features such as sampling grids, periodicity of assessments, permanent and temporary plots, use of remote sensing, sample tree selection, components of forest growth, forest area changes, sampling thresholds, field measurements, drain assessment, involved models and tree parts included in estimates.Conclusion
Increment estimation methods differ considerably among European NFIs. Their harmonisation introduces new issues into the harmonisation process. Recent accomplishments and the increased use of sample-based inventories in Europe make perspectives for harmonised reporting of increment estimation promising.99.
Overview of methods and tools for evaluating future woody biomass availability in European countries
Susana Barreiro Mart-Jan Schelhaas Gerald Kändler Clara Antón-Fernández Antoine Colin Jean-Daniel Bontemps Iciar Alberdi Sonia Condés Marius Dumitru Angel Ferezliev Christoph Fischer Patrizia Gasparini Thomas Gschwantner Georg Kindermann Bjarki Kjartansson Pál Kovácsevics Milos Kucera Anders Lundström Gheorghe Marin Gintautas Mozgeris Thomas Nord-Larsen Tuula Packalen John Redmond Sandro Sacchelli Allan Sims Arnór Snorrason Nickola Stoyanov Esther Thürig Per-Erik Wikberg 《Annals of Forest Science》2016,73(4):823-837