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BACKGROUND: End-systolic volume index (ESVI) is a marker of systolic function, which can be assessed by the geometric (GM, based on Teichholz formula) or 2 planimetric methods (PM, Simpson's derived and length area methods). HYPOTHESIS: Systolic dysfunction (SyD) may be observed in dogs with mitral valve disease (MVD) and is better assessed by PM than GM, which does not take into account the longitudinal left ventricular systolic shortening. ANIMALS: Six healthy dogs were used to determine the variability of the tested variables (Study 1). These variables were then prospectively assessed (Study 2) in 101 small breed dogs: 77 dogs with MVD and 24 healthy controls (CD). METHODS: ESVI was measured by GM and PM in awake dogs. RESULTS: All within- and between-day coefficients of variation were <11% (Study 1). For Study 2, a nonlinear overestimation of ESVI was observed by GM compared with PM. PM-derived ESVI was significantly increased in ISACHC class 3 dogs compared with ISACHC class 1 dogs and exerted a significant influence on cardiac events at 5 months in dogs with MVD from ISACHC classes 2 and 3 (P < .05). CONCLUSIONS AND CLINICAL IMPORTANCE: ESVI can be calculated by GM and PM with good repeatability and reproducibility. However, GM overestimates ESVI in a nonlinear way. Therefore, PM-derived ESVI should be preferred for the detection of SyD that is present at the late stages of the disease.  相似文献   
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The island of Crete (Greece) suffers from an increasingly severe water shortages, coupled with declining groundwater supplies. We compared the costs and benefits of alternative strategies for treating wastewater for use in irrigating vegetables: (1) using a membrane bioreactor (MBR), (2) connecting new residences to centralized wastewater-treatment plants, (3) building new wastewater-treatment plants, and (4) using natural wastewater-treatment systems in rural areas. We also examined the impact of increasing water scarcity on the net benefits of treating wastewater with an MBR. As expected, the value of treated wastewater increases with increasing water scarcity. The net benefit of treating wastewater with an MBR and using the reclaimed water to irrigate vegetables ranges from about 0.02 €/m3 to 2 €/m3 as water scarcity increases. Our results should be helpful in guiding analysts in Greece and other arid countries wishing to evaluate the financial viability of alternative methods of treating wastewater for use in agriculture.  相似文献   
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Background: The clinical outcome of dogs affected by degenerative mitral valve disease (MVD) without overt clinical signs is still poorly defined, and criteria for identification of animals that are at a higher risk of early decompensation have not yet been determined.
Hypothesis: N-terminal pro-B-type natriuretic peptide plasma concentration (NT-proBNP) is correlated with mitral regurgitation (MR) severity and can predict disease progression in dogs with asymptomatic MVD.
Animals: Seventy-two dogs with asymptomatic MVD, with or without heart enlargement (International Small Animal Cardiac Health Council: ISACHC classes 1a and 1b), and a control group of 22 dogs were prospectively recruited.
Methods: Severity of MR was quantitatively assessed from the regurgitation fraction (RF) by the proximal isovelocity surface area method. Consequences of MR were evaluated from measurements of the left atrium/aorta ratio (LA/Ao), fractional shortening (FS), end-diastolic and end-systolic left ventricular volumes indexed to body surface area (EDVI and ESVI). The relevance of these echo-Doppler indices and NT-proBNP for prediction of outcome at 12 months was studied.
Results: A significant correlation was found between NT-proBNP and RF, LA/Ao, FS, and EDVI ( P < .05). NT-proBNP was higher in dogs with MVD (ISACHC classes 1a and 1b) compared with the control group ( P = .025 and < .001, respectively). The difference was not significant when only dogs from ISACHC class 1a with RF < 30% were considered. Lastly, NT-proBNP was higher in dogs that underwent MVD decompensation at 12 months ( P < .05).
Conclusions and Clinical Importance: NT-proBNP is correlated with MVD severity and prognosis in dogs with asymptomatic MVD.  相似文献   
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Purpose  

The aim of our study was to characterise the heterogeneity of sediment distribution in a stormwater retention/infiltration basin (Pont de Cheviré, Nantes, France) and to determine the impact of this distribution on water transfer properties in the soil.  相似文献   
17.
Flexible tubular structures fabricated from solution electrospun fibers are finding increasing use in tissue engineering applications. However it is difficult to control the deposition of fibers due to the chaotic nature of the solution electrospinning jet. By using non-conductive polymer melts instead of polymer solutions the path and collection of the fiber becomes predictable. In this work we demonstrate the melt electrospinning of polycaprolactone in a direct writing mode onto a rotating cylinder. This allows the design and fabrication of tubes using 20 μm diameter fibers with controllable micropatterns and mechanical properties. A key design parameter is the fiber winding angle, where it allows control over scaffold pore morphology (e.g. size, shape, number and porosity). Furthermore, the establishment of a finite element model as a predictive design tool is validated against mechanical testing results of melt electrospun tubes to show that a lesser winding angle provides improved mechanical response to uniaxial tension and compression. In addition, we show that melt electrospun tubes support the growth of three different cell types in vitro and are therefore promising scaffolds for tissue engineering applications.  相似文献   
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Pyrus L. is a taxonomically difficult genus mainly because of interspecific and intergeneric hybridization. A majority of the wild species of Pyrus occurs in Iran, making this region very important for any study of the systematics of the genus. In this investigation, seven quantitative and seven qualitative characters of leaf epidermis, particularly epidermal cells shape, anticlinal walls patterns, type and size of stomata, and cuticular ornamentation of 22 taxa of Pyrus plus Malus orientalis are studied for assessment of their taxonomical value at different levels. Scanning electron microscopy and light microscopy were used for evaluation of epidermis features of these taxa. Some characters such as shape and anticlinal wall pattern of epidermal cells, presence of adaxial stomata, pattern of cuticular ornamentation and epicuticular wax types are useful in separation of some Pyrus taxa. Moreover, Malus orientalis is recognized easily from all Pyrus species via the density of stomata. According to ANOVA analysis, all quantitative variables show high level of between-group differentiation. Also, based on the hierarchical clustering results gained by multiple correspondence analysis and factor analysis of mixed data analyses of the current study, micromorphological characters of epidermal cells reflect the ecological conditions of pear taxa, so most of the mesophyte and xerophyte taxa can be separated from each other in accordance with epidermal cells characters, specially the anticlinal wall pattern. Totally, the application of some other biological markers, particularly suitable molecular data are needed to present well-resolved relationships among these taxa.  相似文献   
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Journal of Soils and Sediments - Assessments of urban soil organic carbon stock (SOCS) are scant because citywide data are scarce. Moreover, we do not know which factors mostly explain SOCS spatial...  相似文献   
20.
A case of corneal sequestrum in a 9-year-old Shih Tzu is reported. On the ophthalmic examination a brown-pigmented ulcer with mild edema and corneal vascularization was present. The brownish plaque was facing an inferior palpebral tumor. A superficial keratectomy followed by a grid keratotomy and removal of the palpebral mass were performed. Histological findings revealed an inflammatory cell infiltration underneath the acellular stromal layers. No melanin granules were observed. No vascular infiltration was present within the necrotic stroma. The surgical area healed and no recurrence has been reported by the owners at the time of writing. To the authors' knowledge, this is the first report of a corneal sequestrum in a dog.  相似文献   
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