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831.
832.
Alessandra Perfetti-Bolaño Lucila Moreno Roberto Urrutia Alberto Araneda Ricardo Barra 《Water, air, and soil pollution》2018,229(12):390
Penguins can bioaccumulate metals, a portion of which can be deposited in the environment through organic remains such as excrement, carcasses, and eggshells. In order to determine Cu and Pb concentrations and their relationship to soil, organic matter and grain size were determined in 27 samples collected in zones without penguins, penguin transit zones, and Adelie (Pygoscelis adeliae), Chinstrap (P. antarctica), and Gentoo penguin (P. papua) colonies on the Ardley Peninsula, Maritime Antarctica. An atomic absorption spectrophotometry analysis was carried out, organic matter was determined by loss on ignition, and grain size was measured with a laser diffraction particle size analyzer. The principal component analysis shows a relationship between the variables Cu, Pb, and grain size and areas with penguin presence. Cu concentrations in soils varied among areas (χ2, 15.707; p =?0.0004), with higher concentrations in transit zones and penguin colonies (142.63 and 140.79 mg/kg, respectively) than in zones without penguins (83.33 mg/kg). Pb concentrations in soils also varied among areas (χ2, 6.5029; p =?0.0387), and were higher in transit zones (5.92 mg/kg) than in the penguin colonies (4.45 mg/kg). Grain size differed significantly among areas (χ2, 13.506; p =?0.0012), with higher values in transit zones (avg. 37.38 μm) than in penguin colonies (avg. 26.93 μm) and zones without penguins (avg. 20.72 μm). Organic matter did not differ significantly among the studied zones (χ2, 2.0882; p =?0.3520). There is a positive correlation between Cu-Pb (Rho, 0.5532; p =?0.0028), Cu-grain size (Rho, 0.4756; p =?0.0130) and Pb-grain size (Rho, 0.4879; p =?0.0098). The presence of penguins increases Cu concentrations in Antarctic soils due to its bioaccumulation and elimination through excrement; however, the presence of penguins has a minor influence on Pb concentration in soil, probably because this metal is stored efficiently in bones, feathers, and eggshells. 相似文献
833.
Gorgonio López-Tolentino Adrián Méndez-Prieto A. Javier Lozano-del Río Ricardo H. Lira-Saldivar José H. Valenzuela-Soto 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(1):77-84
The use of plastic mulch is associated with a higher increase in yield of vegetables. However, at the end of the growing season for each crop, plastic mulching can create environmental pollution that can cause negative impacts on the environment that could be solved by the use of degradable plastics. The aim of this study was to determine the effect of oxo-degradable plastic mulches on soil temperature, growth, gas exchange, and cucumber crop yield. The study was conducted in two locations in the northeast of Mexico during the spring and summer of 2013. The plastic mulch colors with additives were blue, green, and red and each color having 8% and 12% of pigment and 22% and 23% of Titanium dioxide (Rutile). The resultant treatments were compared with the black plastic mulch, which is the standard plastic in the world, and bare soil in a randomized complete block design with three replications in two locations. The mean soil temperature at both locations was statistically higher in black plastic mulch, followed by the oxo-degradable plastics mulches and lowest in the control. Gas exchange was not affected by plastic mulches. SPAD units as the index of chlorophyll content in leaves were very little affected by plastic mulch. Both, commercial and total yield were statistically similar in the oxo-degradable plastic mulches and the black plastic mulch, and lowest in the control. Plastics with higher concentrations of pigment registered higher degradation in both locations. Our results suggest that different plastic mulches impact positively on the yield of cucumber crop. The benefit in yield by the different plastic mulches in the conditions of this study was due to their soil warming ability that results in improved soil temperature, leaf area, and plant dry weight. 相似文献
834.
Claudio C. Natalini Carolina L. Krahn Priscila B.S. Serpa Joanna E. Griffith Ricardo Miyasaka de Almeida 《Veterinary anaesthesia and analgesia》2017,44(2):219-227
Objective
To investigate the efficacy of a new intravenous (IV) nanoemulsified isoflurane formulation for maintenance of general anesthesia in dogs.Study design
Prospective, crossover, experimental study.Animals
Seven healthy, mature, mixed-breed dogs, three male and four female, weighing 11.5 ± 1.5 kg.Methods
Anesthesia was induced with propofol for instrumentation. Measurements were obtained before administration of either inhaled isoflurane (Iso-I) or IV 15% isoflurane-loaded lipid nanoemulsion (Iso-nano). The minimum alveolar concentration (MAC) of isoflurane was determined using the ‘up-and-down’ technique. A tail clamp was applied every 15 minutes for a total time of 90 minutes and isoflurane administration was adjusted according to the response. Data were recorded at 30, 60 and 90 minutes for end-tidal isoflurane concentration (Fe´Iso), end-tidal carbon dioxide partial pressure (Pe′CO2), inspired isoflurane concentration (FIIso), arterial hemoglobin oxygen saturation (SaO2), peripheral hemoglobin oxygen saturation (SpO2), respiratory rate (fR), heart rate (HR), arterial blood pH, PaCO2, PaO2, base excess (BE), bicarbonate (HCO3?), systemic arterial pressure (sAP), and biochemical variables of blood urea nitrogen, alanine aminotransferase, creatine kinase and creatinine.Results
No significant differences between treatments were detected for HR, fR, SaO2 or any biochemical variables (p > 0.05). In the Iso-nano treatment, sAP was significantly decreased throughout the study. Significant decreases in pH, Pe′CO2, BE and HCO3? were measured in the Iso-nano treatment. Isoflurane MAC was significantly lower in the Iso-nano than the Iso-I treatment. The dose of isoflurane (g hour?1) required to maintain general anesthesia did not differ significantly between treatments.Conclusions and clinical relevance
Administration of 15% isoflurane-loaded lipid nanoemulsion IV was effective in maintaining general anesthesia in dogs but did not reduce the amount of isoflurane necessary to maintain general anesthesia. Significant hypotension and nonrespiratory acidosis occurred with the injectable form. 相似文献835.
Radical Cystectomy and Cutaneous Ureterostomy in 4 Dogs with Trigonal Transitional Cell Carcinoma: Description of Technique and Case Series 下载免费PDF全文
836.
Gerbert Sylvestre Dossa Rolando Torres Amelia Henry Ricardo Oliva Edgar Maiss Casiana Vera Cruz Kerstin Wydra 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(1):115-127
Plant response to one type of stress can be affected by simultaneous exposure to a second stress, for example when abiotic and biotic stresses occur together. Ten rice genotypes comprising those with bacterial blight (BB) resistance (R) genes, drought quantitative trait loci (QTLs) plus a BB R gene, and BB susceptible genotypes, were subjected to mild and moderate drought stress and plants were inoculated with two Xoo strains (PXO99 and PXO145) to simulate the challenges rice crops face under simultaneous stress of drought and BB. Plant height and dry shoot biomass were significantly reduced by drought stress treatments. The BB disease lesion lengths varied according to rice genotypes and PXO99 Xoo multiplication and spread in planta was higher compared to that of PXO145, which generally decreased under mild drought stress. Rice genotype IRBB7 (Xa7) showed less Xoo spread and a reduced Xoo multiplication under drought stress compared to the well-watered control with PXO145. In contrast, in genotypes with a different BB R gene and/or drought QTLs [IRBB4 (Xa4), IR87705–6-9-B (Xa4 + qDYT 2.2 ), IR87707–445-B-B-B (Xa4 + qDYT 2.2 + qDYT 4.1 ) and IR87707–446-B-B-B (Xa4 + qDYT 2.2 + qDYT 4.1 )], Xoo multiplication and spread in planta was higher with drought stress. This study has shown that drought stress affected rice response to the BB pathogen and the response varied according to the rice genotype. It is concluded that evaluating rice varieties under combined abiotic and biotic stresses will be the best strategy to determine biotic stress resistance durability under climate change. 相似文献
837.
Kamila Câmara Correia João Victor Jansen de Queiroz Ricardo Brainer Martins Alessandro Nicoli Emerson Medeiros Del Ponte Sami Jorge Michereff 《European journal of plant pathology / European Foundation for Plant Pathology》2017,149(2):269-276
A standard area diagram set (SADs) with eight severity values ranging from 0.5 to 32% was evaluated as a tool to improve the accuracy of the estimates of Phomopsis leaf blight severity on eggplant by ten inexperienced raters. A first assessment in a 50-leaf dataset of digital images was performed unaided (UN, no SAD). Two further aided (A) assessments, conducted two (A1) and four weeks after the first (A2) unaided one were performed. The precision of the estimates, as indicated by the Pearson’s correlation coefficient (r), improved significantly when using the aid (A1: r = 0.96 and A2: r = 0.96) compared to unaided (UN: r = 0.79). However, the generalized bias (C b) was not significantly affected because the unaided estimates were already quite accurate (C b = 0.93). The overall concordance (ρ c) was significantly improved due to the large gains in precision when using the SADs. The raters’ estimates were more uniform (ρ c > 0.9) when using the aid, with progressive gains in the reliability of the estimates among them, indicated by the concordance correlation coefficient statistics. The SADs proposed in this study will be useful in severity estimation during field work involving multiple raters, especially as use of the SADs results in less variable estimates, improving accuracy and reliability among raters. 相似文献
838.
Potential risk levels of invasive Neoleucinodes elegantalis (small tomato borer) in areas optimal for open‐field Solanum lycopersicum (tomato) cultivation in the present and under predicted climate change 下载免费PDF全文
839.
Michael Heym Ricardo Ruíz-Peinado Miren Del Río Kamil Bielak David I. Forrester Gerald Dirnberger Ignacio Barbeito Gediminas Brazaitis Indrė Ruškytkė Lluís Coll Marek Fabrika Lars Drössler Magnus Löf Hubert Sterba Václav Hurt Viktor Kurylyak Fabio Lombardi Dejan Stojanović Jan Den Ouden Renzo Motta Maciej Pach Jerzy Skrzyszewski Quentin Ponette Géraud De Streel Vit Sramek Tomáš Čihák Tzvetan M. Zlatanov Admir Avdagic Christian Ammer Kris Verheyen Buraczyk Włodzimierz Andrés Bravo-Oviedo Hans Pretzsch 《Annals of Forest Science》2017,74(3):63
Key message
This data set provides unique empirical data from triplets of Scots pine ( Pinus sylvestris L.) and European beech ( Fagus sylvatica L.) across Europe. Dendrometric variables are provided for 32 triplets, 96 plots, 7555 trees and 4695 core samples. These data contribute to our understanding of mixed stand dynamics. Dataset access at http://dx.doi.org/10.5061/dryad.8v04m . Associated metadata available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/?uuid=b3e098ca-e681-4910-9099-0e25d3b4cd52&hl=eng .840.
Ricardo A. Torres-Palma John Gibson Ian G. Droppo Peter Seto Ramin Farnood 《Water, air, and soil pollution》2017,228(3):106
Ultraviolet (UV) disinfection of wastewater is adversely affected by the presence of particle-associated bacteria. Earlier studies have shown that disrupting these particles by ultrasonic cavitation can enhance the UV disinfection of wastewater. However, the use of ultrasound as a pretreatment technology for UV disinfection is hindered by its high energy demand. In this work, the addition of several organic solutes, including 1-propanol, 1-hexanol, and pentyl acetate, to promote the cavitation process and to improve the breakage of wastewater particles was examined. It was found that the enhancement in the cavitation and the breakage efficiency of particles was positively related to the hydrophobicity of surfactant. In addition, particle breakage was a function of the concentration of surfactant as well as the delivered ultrasound energy density. Sonication of wastewater samples containing small amounts of 1-hexanol (16 mM) or pentyl acetate (12 mM) increased the UV disinfection efficiency and decreased the required UV dose to achieve the disinfection target by a factor of more than 2.5. 相似文献