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1.
Ultrasonography is currently used in veterinary medicine to examine the anatomy and physiology of internal organs and to establish normal standards for exotic animal species. Specifically, the kidneys may be evaluated and measured in length, width, and height. The kidneys in 33 oncilla (Leopardus tigrinus), including 20 males and 13 females, were opportunistically located, characterized, and measured by ultrasound using a 7.5-MHz linear transducer at two different zoologic facilities in S?o Paulo, Brazil. Renal volume was calculated from these linear measurements. The mean linear measurements and volume of the right and left kidneys were not significantly different.  相似文献   
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Agroforestry Systems - The use of native trees in agroecosystems is a promising way to increase litter deposition and nutrient cycling and foster the recovery of degraded areas, especially in...  相似文献   
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Purpose

Soil carbon dynamics were studied at four different forest stands developed on bedrocks with contrasting geology in Slovenia: one plot on magmatic granodiorite bedrock (IG), two plots on carbonate bedrock in the karstic-dinaric area (CC and CD), and one situated on Pleistocene coalluvial terraces (FGS).

Materials and methods

Throughfall (TF) and soil water were collected monthly at each location from June to November during 2005–2007. In soil water, the following parameters were determined: T, pH, total alkalinity, concentrations of Ca2+ and Mg2+, dissolved organic carbon (DOC), and Cl? as well as δ13CDIC. On the other hand, in TF, only the Cl? content was measured. Soil and plant samples were also collected at forest stands, and stable isotope measurements were performed in soil and plant organic carbon and total nitrogen and in carbonate rocks. The obtained data were used to calculate the dissolved inorganic carbon (DIC) and DOC fluxes. Statistic analyses were carried out to compare sites of different lithologies, at different spatial and temporal scales.

Results and discussion

Decomposition of soil organic matter (SOM) controlled by the climate can explain the 13C and 15?N enrichment in SOM at CC, CD, and FGS, while the soil microbial biomass makes an important contribution to the SOM at IG. The loss of DOC at a soil depth of 5 cm was estimated at 1 mol m?2 year?1 and shows no significant differences among the study sites. The DOC fluxes were mainly controlled by physical factors, most notably sorption dynamics, and microbial–DOC relationships. The pH and pCO2 of the soil solution controlled the DIC fluxes according to carbonate equilibrium reactions. An increased exchange between DIC and atmospheric air was observed for samples from non-carbonate subsoils (IG and FGS). In addition, higher δ13CDIC values up to ?19.4?‰ in the shallow soil water were recorded during the summer as a consequence of isotopic fractionation induced by molecular diffusion of soil CO2. The δ13CDIC values also suggest that half of the DIC derives from soil CO2 indicating that 2 to 5 mol m?2 year?1 of carbon is lost in the form of dissolved inorganic carbon at CC and CD after carbonate dissolution.

Conclusions

Major difference in soil carbon dynamics between the four forest ecosystems is a result of the combined influence of bedrock geology, soil texture, and the sources of SOM. Water flux was a critical parameter in quantifying carbon depletion rates in dissolved organic and inorganic carbon forms.
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BACKGROUND: The tomato leafminer (Tuta absoluta Povolny) has rapidly colonised the whole Mediterranean and South‐Atlantic coasts of Spain, and it has become a key problem in both outdoor and greenhouse crops. New control methods compatible with biological control are required, and mating disruption appears to be a perfect method in current agriculture, as it is an environmentally friendly and residue‐free technique. IPM packages tested have included the use of pheromones to detect populations, but there has not been much previous research on mating disruption of T. absoluta. In this work, pheromone doses varying from 10 to 40 g ha?1, emitted at a constant rate over 4 months, were tested in greenhouses with different levels of containment in order to evaluate the efficacy of mating disruption on T. absoluta. RESULTS: Trials on containment level revealed that the flight of T. absoluta was satisfactorily disrupted with an initial pheromone dose of 30 g ha?1, and levels of damage did not significantly differ from those in reference plots with insecticide treatments. Later efficacy trials confirmed previous experiences, and release studies showed that control of damage and flight disruption were taking place when releasing at least 85 mg pheromone per ha per day. CONCLUSION: Effective control using pheromone application against T. absoluta can be achieved, in greenhouses with high containment levels, for 4 months, with initial doses of 30 g ha?1. Further research must be conducted in order to evaluate the prospect of outdoor application of mating disruption systems. Copyright © 2011 Society of Chemical Industry  相似文献   
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Sugar and starch levels were determined in leaves, fruits, bark and roots of the ‘Navelate’ variety (low yield) and compared with those of ‘Washington Navel’ (standard yield). Old leaves had the lowest sugar content in May, while young leaves had a decreasing content from spring to summer in both varieties. ‘Navelate’ had lower sugar content in leaves, bark and roots than ‘Washington Navel’. Starch levels in the leaves showed a maximum towards the end of May. In winter, ‘Navelate’ had a higher starch content, mainly in the roots and bark, due to its low yield.  相似文献   
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This paper describes a polymerase chain reaction (PCR)-based method performed on blood samples and intestinal content to detect subclinical pigeon circovirus (PiCV) infection in live pigeons. In addition, two sets of primers (primer set 1 and 2), designed in two different regions of the viral genome, were used to provide evidence of possible differences in PCR responses. Blood and intestinal content samples were randomly collected from a total of 50 apparently healthy meat pigeons, aged 1 to 5 wk, which came from central Italy. Samples of primary lymphoid organs were also collected. Results showed a high level of PiCV infection, although clinical signs were not present. The results obtained with the two sets of primers showed that primer set 2 was able to detect a higher number of PCR-positive pigeons (45 of 50 pigeons) than primer set 1 (11 of 50 pigeons). In both cases an increase in positive results with pigeon age indicates that the major direction of transmission is likely horizontal. In these circumstances feces can play an important epidemiologic role, as supported by the consistent circovirus detection in intestinal content. The high sensitivity of this PCR test, which is able to detect very low amounts of viral DNA (5.5 x 10(-3) fg of plasmid containing the cloned PiCV genome), makes it suitable for possible application as an epidemiologic tool for identifying virus carriers for subsequent removal from lofts.  相似文献   
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Thirty-fourformae speciales (ff.sp.) ofFusarium oxysporum which have been subjected to vegetative compatibility group (VCG) analysis are listed, along with their updated 3-digit numerical codes. Ten of these ff.sp. are listed for the first time, bringing to 49 the total number of VCG-analyzed, listed ff.sp. New and corrected entries are tabulated for the remaining 24 ff.sp.  相似文献   
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