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Objectives(1) To investigate heart morphology and function using echocardiography and tissue Doppler imaging (TDI), (2) to determine heart disease prevalence and characteristics, and (3) to assess potential genetic features in a population of Sphynx cats presented for cardiovascular screening.AnimalsA total of 147 echocardiographic examinations, including 33 follow-ups, were performed by trained observers on 114 Sphynx cats of different ages (2.62 ± 1.93 years [0.5–10.0]) from 2004 to 2011.MethodsSphynx cats underwent a physical examination, conventional echocardiography, and, if possible, two-dimensional color TDI.ResultsConventional echocardiographic findings included 75/114 normal (65.8%) and 39/114 (34.2%) abnormal examinations with a diagnosis of either congenital heart diseases (n = 16) or hypertrophic cardiomyopathy (HCM, n = 23). In adult healthy cats, a significant body weight effect was observed for several echocardiographic variables, including end-diastolic left ventricular (LV) free wall (P < 0.01), interventricular septum (P < 0.001), and LV diameter (P < 0.001). Mitral valve dysplasia (MVD) was observed as a single or associated defect in 15/16 cats with congenital heart diseases. A significant increase in HCM prevalence (P < 0.001) was observed according to age. The pedigree analysis of a large family (n = 81) suggested an autosomal dominant mode of inheritance with incomplete penetrance for HCM.ConclusionsBody weight should be taken into account when interpreting values of diastolic myocardial wall thicknesses in Sphynx cats. Additionally, HCM and MVD are two relatively common heart diseases in this feline breed. More pedigree data are required to confirm the inheritance pattern of HCM at the breed level.  相似文献   
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We studied the long-term effects of disturbance within the Northwest Wisconsin (USA) Sand Plain (NWSP), an ecoregion that is characterized by very sandy soil and an active disturbance history that includes fire, agriculture and industrial forestry, largely clearcut logging of jack pine (Pinus banksiana) and aspen (Populus spp.). Open “barrens” communities on this landscape were formerly maintained by fire, and are a high conservation priority. Hill's Oak (Quercus ellipsoidalis) can also dominate forest canopies, while blueberry (Vaccinium angustifolium), and sweetfern (Comptonia peregrina) are common shrub species. We structured a field sampling design with a spatial-temporal database built from historic airphotos (1938 and 1997) and fire records to examine whether soil organic matter and nutrients vary with disturbance history in the nonforest habitats of the sand plain. We sampled soils along 83 transects, randomly stratified among five sampled classes: (1) nonforest-farming history; (2) nonforest-fire history; (3) nonforest-clearcut only history; (4) evergreen forest of jack pine and red pine (P. resinosa); and (5) deciduous forest of Hill's oak and aspen. Logging of the original forest took place in the late 1800s–early 1900s. The farms were abandoned between 1938 and 1960, and the most recent fire occurred in 1977. Thus, the duration of the agricultural legacy is approximately 45–65 years while observed fire effects have lasted for 26 years.We observed strong agricultural legacies, including high P and low OM, N and Ca. One possible explanation for the N legacy is that it is tied to soil OM accretion which may be driven by plant growth. We detected no difference in mean values for any of the soil properties between soils from nonforested areas within the Five-Mile fire and soils from nonforested areas with a clearcut-only history. We did observe a fire effect in high variance for soil P. This could have resulted from variations in fire severity and ash convection and deposition.Forest soils generally had lower pH than the nonforest soils, and the deciduous forest soils had the lowest pH and also very low Ca. We also observed high within-transect coefficient of variation for Ca in the forest soils.We conclude that agriculture is a qualitatively different disturbance-type than fire or clearcutting, that disturbance legacies tend to be most persistent with geologically stable elements, such as P, and that management and conservation planning within the NWSP would benefit from site-specific agricultural history, as well as attention to Ca.  相似文献   
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BACKROUND: In the present study, the effect of thiamethoxam and clothianidin on the locomotor activity of American cockroach, Periplaneta americana (L.), was evaluated. Because it has been proposed that thiamethoxam is metabolised to clothianidin, high‐performance liquid chromatography coupled with mass spectrometry was used to evaluate the amount of clothianidin on thiamethoxam‐treated cockroaches. RESULTS: One hour after neonicotinoid treatment, the time spent in the open‐field‐like apparatus significantly increased, suggesting a decrease in locomotor activity. The percentage of cockroaches displaying locomotor activity was significantly reduced 1 h after haemolymph application of 1 nmol g?1 neonicotinoid, while no significant effect was found after topical and oral administration. However, at 24 and 48 h, all neonicotinoids were able to reduce locomotor activity, depending on their concentrations and the way they were applied. Interestingly, it was found that thiamethoxam was converted to clothianidin 1 h after application, but the amount of clothianidin did not rise proportionately to thiamethoxam, especially after oral administration. CONCLUSION: The data suggest that the effect of thiamethoxam on cockroach locomotor activity is due in part to clothianidin action because (1) thiamethoxam levels remained persistent 48 h after application and (2) the amount of clothianidin in cockroach tissues was consistent with the toxicity of thiamethoxam. Copyright © 2010 Society of Chemical Industry  相似文献   
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The phenolic compounds of 'Green Gage' (GG) plums ( Prunus domestica L.), "Rainha Claudia Verde", from a 'protected designation of origin' (PDO), in Portugal, were quantified in both flesh and skin tissues of plums collected in two different orchards (GG-V and GG-C). Analyzes of phenolic compounds were also performed on another GG European plum obtained in France (GG-F) and two other French plums, 'Mirabelle' (M) and 'Golden Japan' (GJ). Thiolysis was used for the first time in the analysis of plum phenolic compounds. This methodology showed that the flesh and skin contain a large proportion of flavan-3-ols, which account, respectively, for 92 and 85% in GJ, 61 and 44% in GG-V, 62 and 48% in GG-C, 54 and 27% in M, and 45 and 37% in GG-F. Terminal units of procyanidins observed in plums are mainly (+)-catechin (54-77% of all terminal units in flesh and 57-81% in skin). The GJ plums showed a phenolic composition different from all of the others, with a lower content of chlorogenic acid isomers and the presence of A-type procyanidins as dimers and terminal residues of polymerized forms. The average degree of polymerization (DPn) of plum procyanidins was higher in the flesh (5-9 units) than in the skin (4-6 units). Procyanidin B7 was observed in the flesh of all GG plums and in the skin of the Portuguese ones. Principal component analysis of the phenolic composition of the flesh and skin of these plums obtained after thiolysis allowed their distinction according to the variety and origin, opening the possibility of the use of phenolic composition for variety/origin identification.  相似文献   
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Background

Plant root systems play a major role in anchoring and in water and nutrient uptake from the soil. The root cone angle is an important parameter of the root system architecture because, combined with root depth, it helps to determine the volume of soil explored by the plant. Two genes, DRO1 and SOR1, and several QTLs for root cone angle have been discovered in the last 5 years.

Results

To find other QTLs linked to root cone angle, a genome-wide association mapping study was conducted on two panels of 162 indica and 169 japonica rice accessions genotyped with two sets of SNP markers (genotyping-by-sequencing set with approximately 16,000 markers and high-density-rice-array set with approximately 300,000 markers). The root cone angle of all accessions was measured using a screen protractor on images taken after 1 month of plant growth in the Rhizoscope phenotyping system. The distribution of the root cone angle in the indica panel was Gaussian, but several accessions of the japonica panel (all the bulus from Indonesia and three temperate japonicas from Nepal or India) appeared as outliers with a very wide root cone angle. The data were submitted to association mapping using a mixed model with control of structure and kinship. A total of 15 QTLs for the indica panel and 40 QTLs for the japonica panel were detected. Genes underlying these QTLs (+/?50 kb from the significant markers) were analyzed. We focused our analysis on auxin-related genes, kinases, and genes involved in root developmental processes and identified 8 particularly interesting genes.

Conclusions

The present study identifies new sources of wide root cone angle in rice, proposes ways to bypass some drawbacks of association mapping to further understand the genetics of the trait and identifies candidate genes deserving further investigation.
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