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91.
The tomato fruit quality results of biochemical and physiological changes that occur during the ripening process. Although, the pericarp total protein profiles are less polymorphic than DNA-based markers the polymorphism in those could be directly associated with fruit quality traits. The aim of this work was to identify associations between polymorphic polypeptides from fruit pericarp at two ripening stages and fruit quality traits evaluated in two segregating populations of tomato. A cross between a normal ripening cultivar of Solanum lycopersicum (C, Caimanta) and a genotype carrying the nor (non ripening) gene (N) as well as a cross between Caimanta and a cherry type tomato of S. lycopersicum var. cerasiforme (Ce) showed genetic variance for several fruit quality traits such as fruit weight, shape, solids soluble content, acidity, color and fruit shelf life. The quantitative variations observed at phenotypic level had correspondence with the polymorphism detected in the protein profiles. Indeed, the polymophic polypeptides associated with quality fruit traits and fruit shelf life would be useful to assist tomato breeding programs as protein molecular markers.  相似文献   
92.
Roads can have drastic impacts on wildlife populations. Although there is wide recognition of the negative impacts caused by roads and a wealth of practical studies, there is a lack of theoretical work that can be used to predict the impact of road networks or to implement mitigation measures. Here, using Skellam’s diffusion model, we develop analytic and numerical approaches to analyze the impact of road networks on the survival of populations. Our models show that the viability of a population is determined not only by road density but also by the size and shape of patches. Accordingly, we studied the minimum size of a patch to sustain a population with given diffusion and growth parameters. We provide simple formulas to estimate the minimum patch size, and illustrate the importance of shape with square and rectangular patches. Our models also allow the estimation of time to extinction after road construction for a population in a patch smaller than that of the minimum size. Finally, using numerical computations we illustrate how the spatial arrangement of fences strongly affects both the equilibrium density and the spatial distribution of populations, and that not all fence layouts are equally effective. We anticipate that our methods provide a tool to assess the impact of geometrical features of road networks on wildlife and that they can be used to design mitigation measures to prevent the decline and extinction of populations in an anthropogenically disturbed landscape.  相似文献   
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Recent research is underway to study cork oak (Quercus suber L.) wood potential for production of wood components. A total of 35 stems of young and mature cork oaks were sampled, live sawn into flitches, scanned using VTT’s WoodCIM®, and the measured data computed by VTT’s PuuPilot software, allowing stem 3D reconstruction. Sawing simulations were run for 0.5 m and 1 m logs and the whole stem. Sawn products were (1) planks, (2) parquet, (3) lamparquet, and (4) external component of multilayer planks. Cork oak stems showed a moderate to small taper (mean 24 mm/m). Curviness varied between straight to significantly crooked stems (mean value 40 mm) Batch yields for the tested products ranged 25–43% and 37–50% for 0.5 m logs of young and mature trees, respectively; for 1 m logs, batch yields ranged 19–41% and 25–54%. When using the whole stem, batch yields were lower, ranging 11–38% and 15–50%. Higher yields were obtained for all log lengths and samples for production of lamparquet, parquet, and multilayer component.  相似文献   
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Objective To compare intraocular pressure (IOP) measurements made on healthy adult rabbits without the effect of tranquilizers using the new applanation tonometer, Tono‐Pen Avia®, and the rebound tonometer Tonovet®. Methods Intraocular pressure was measured throughout the day (6:00, 9:00, 12:00, 15:00, and 18:00 h) in 38 adult New Zealand White rabbits (76 eyes). The animals were 20 males and 18 females, with a mean weight of 3.5 kg and an average age of 6 months. A complete ocular exam (including Schirmer tear test, fluorescein staining, slit‐lamp biomicroscopy, and direct ophthalmoscopy) was performed on all animals at the beginning of the trial. Rebound tonometry was performed, and after 10 min, anesthetic drops were instilled and applanation tonometry was carried out. IOP values obtained using the two techniques were analyzed statistically. Results The mean IOP was 9.51 ± 2.62 mmHg with Tonovet®, and 15.44 ± 2.16 mmHg with the Tono‐Pen Avia®. Significant differences between measurements with the two tonometers were observed (P < 0.001). The linear regression equation describing the relationship between the two tonometers was y = 0.4923x + 10.754 (y = Tonovet® and x = Tono‐Pen Avia®). High IOPs were recorded in the early measurements (6:00), but the average IOPs from both devices were statistically similar throughout the day (P = 0.086). The correlation coefficient was r2 = 0.357. No significant difference in IOP regarding gender was observed. Conclusion The Tono‐Pen Avia® recorded higher levels of IOP compared with the Tonovet®. Early in the day, the IOP of rabbits was higher than later in the day, regardless of the tonometer used.  相似文献   
97.
Aquatic macrophytes are well known accumulators for heavy metals, the reason why they are used as bioindicators for water quality and in phytoremediaton strategies. This study reports on the elemental concentrations in four free-floating aquatic macrophytes (S. auriculata; P. stratiotes; E. crassipes and E. azurea) growing in two water reservoirs (Santana e Vigário, Rio de Janeiro State, Brazil) of an electric power plant that receive input from the polluted Paraíba do Sul River. Filtered water samples and water suspended solids from these environments were also analysed. Inductively coupled plasma mass spectrometry was used as the principal method, allowing the determination of up to 41 elements, including the rare-earth elements (REEs) and other trace metals not assayed before in these macrophytes. The results show that all elements studied are accumulated by the macrophytes with concentration ratios (CR = [plant]: [water]) varying from about 1,000 to 200,000, based on the dry weight of the plant species. With a few exceptions, highest accumulations were observed in E. crassipes in which CRs increase in the sequence: Cu < Mo < Cr < Pb < Tl < Fe < La < Zn < Ce< Mn. Surprisingly high CRs (e.g. Ce: 74,000) and corresponding mass concentrations were observed for the rare-earth elements (e.g. ∑REE: 112 mg kg?1), also measured in the water suspended particle fraction. The results show that this fraction acts as an effective sink for trace metals in the aquatic system studied and seems to play also an important role in the transfer of metals from water to the plant species.  相似文献   
98.
A catena developed on gabbro in Galicia, N.W. Spain, was studied. The methods utilized, consisting of macro- and microscopic mineralogical and morphological observation, allowed the identification of different features produced by the action of pedological and geomorphological processes. The application of Butler's K cycle concept allows a relative sequence of events to be established in which pedogenetic processes are integrated within the general framework of the evolutionary history of the slope. Five K cycles could be recognized, beginning with a phase of deep weathering and ending with the present phase of incipient soil formation. In between feature a.o. phases of solifluxion, the formation of an argillic horizon and the development of a stoneline.  相似文献   
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The objective was to study the essential oil composition of coriander fruits in plants growing in environments differing in soil conditions and weediness level. Factorial field experiments were conducted in two locations from the Rolling Pampas, Argentina, and two coriander landraces (European and Argentinean) were tested under two levels of nitrogen fertilization and weediness. Data were evaluated with uni- and multivariate techniques. The variation in the oil composition was related to the relative proportion of the constituents and not to the presence/absence of a particular component. Weather conditions in 1997 favored linalool and camphor in both landraces. Location, fertilization, and weediness also affected the chemical profile. The European landrace showed a more stable concentration of the major components than the Argentinean landrace. These results, which show the relationships between some environmental conditions and the essential oil composition, are useful in the development of innovative strategies aimed to improve oil composition and to manage crop pests.  相似文献   
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