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41.
The morphology of parcel patterns created by humans both in urban and rural areas is investigated. The parcel size distribution function, f(a), provides a criterion, that enables unambiguous classification of each piece of land as city core, suburbs, or rural area. The morphology of the rural area corresponds to a scale-free structure and follows a power-law distribution f(a) ~ a n of the parcel areas with the exponent n ≈ 1. In suburbs, the area distribution follows the log-normal distribution. In the city core, f(a) has an unimodal shape with an algebraically decaying tail, n = 2. Our study is based on data originating mainly from North America, the Hawaiian Islands, and Australia. For the regions analyzed, the characteristics of the parcel size distribution are universal and robust with respect to geographical, historical, and economical conditions accompanying development of a given area. The urbanization process can be described in terms of the changes of the morphology of the patterns of land fragmentation. In this formulation, the rural morphology, which can be thought as natural one because it exhibits a scale-free distribution of parcel sizes, is transformed into the artificial morphology developed in the city centers. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
42.
Atopic dermatitis is a common allergic skin disease in dogs. The aim of this study was to examine the possibility of a correlation between biophysical skin variables: skin hydration (SH), skin pH, and erythema intensity measured in 10 different body regions and both total Canine Atopic Dermatitis Extent and Severity Index (CADESI-03) and CADESI measured in a given region (CADESI L). The study was conducted using 33 dogs with atopic dermatitis. The assessment of the biophysical variables was done in 10 body regions: the lumbar region, right axillary fossa, right inguinal region, ventral abdominal region, right lateral thorax region, internal surface of the auricle, interdigital region of right forelimb, cheek, bridge of nose, and lateral site of antebrachum. Positive correlations were found between SH and CADESI L for the following regions: the inguinal region (r = 0.73) and the interdigital region (r = 0.82), as well as between total CADESI and SH on digital region (r = 0.52). Also, positive correlations were reported for skin pH and CADESI L in the lumbar region (r = 0.57), the right lateral thorax region (r = 0.40), and the lateral antebrachum (r = 0.35). Positive correlations were found in the interdigital region between erythema intensity and the total CADESI-03 (r = 0.60) as well as the CADESI L (r = 0.7). The results obtained suggest that it may be possible to use skin hydration, pH, and erythema intensity to assess the severity of skin lesion but positive correlation was only found in < 13.3% of possible correlations and usage of these measures in dogs is limited.  相似文献   
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44.
Enrofloxacin is a concentration-dependent antimicrobial used in bacterial infections in poultry. During a few months of a turkey's life, pharmacokinetics of drugs undergoes substantial changes which may compromise their efficacy due to variability in internal exposure (measured by area under the concentration–time curve, AUC). The aim of this study was to describe the effects of age on the pharmacokinetics of a single intravenous (i.v.) and oral administration of enrofloxacin at a dose of 10 mg/kg to turkeys. It was found that during a 2.5-month-long period of growth from 1.4 to 14.6 kg, the AUC after i.v. administration increased almost threefold due to a significant decrease in the body clearance (from a mean of 0.76–0.28 L hr−1 kg−1). Over the same period, the mean elimination half-life was prolonged from 2.65 to 7.03 hr. Oral administration resulted in a similar trend in pharmacokinetic parameters. For both routes, formation of the major metabolite, ciprofloxacin, was marginal. Protein binding was not age-dependent and never exceeded 50%. Body clearance, volume of distribution and elimination half-life were subjected to an allometric analysis and a novel, nonlinear dosage protocol has been proposed to improve the internal exposure to the drug in different age groups of turkeys.  相似文献   
45.
Authentication of seed provenance is an importance issue to avoid the negative impact of poor adaptation of progenies when planted outside their natural environmental conditions. The objective of this study was to evaluate the potential of near infrared (NIR) spectroscopy as rapid and non-destructive method for authentication of Picea abies L. Karst seed provenances. For this purpose, five seed lots from Sweden, Finland, Poland and Lithuania each were used. NIR reflectance spectra were recorded on individual seeds (n = 150 seeds × 5 seed lots × 4 provenances = 3000 seeds) using XDS Rapid Content Analyzer from 780 to 2500 nm with a resolution of 0.5 nm. Classification model was developed by orthogonal projection to latent structures-discriminant analysis. The performance of the computed classification model was validated using two test sets—internal (the same seed lots as the model but excluded during model development; n = 600 seeds) and external (seed lots not included in the model; n = 1158 seeds). For the internal test, the model correctly recognized 99% of Swedish, Finnish and Polish samples and 97% of Lithuanian seeds. For the external test samples, the model correctly assigned 81% of Swedish, 96% of Finnish, 98% of Lithuanian and 93% of Polish seeds to their respective classes. The mean classification accuracy was 99 and 95% for internal and external test set, respectively. The spectral differences among seed lots were attributed to differences in chemical composition of seeds, presumably fatty acids and proteins, which are the dominant storage reserves in P. abies seeds. In conclusion, the results demonstrate that NIR spectroscopy is a very promising method for monitoring putative seed provenances and in seed certification.  相似文献   
46.
47.

Context

Black poplar (Populus nigra L.) is an alluvial forest tree species whose genetic pool is decreasing in Europe. Poplar trees produce short-lived seeds that do not store well.

Aim

The feasibility of seed storage in conventional and cryogenic conditions after their desiccation from water content (WC) of 0.15 to 0.07 g H2O g?1 dry mass (g g?1) was investigated.

Methods

Seed germinability was evaluated (seeds with a radicle and green cotyledons were counted) after storage of seeds for a period of 3 to 24 months at different temperatures: 20°, 10°, 3°, ?3°, ?10°, ?20° or ?196°C.

Results

Seeds desiccated to a 0.07 g g?1 WC can be stored successfully at ?10 °C and ?20 °C for at least 2 years. A significant decrease in germination was observed only after 12 months of seed storage (WC 0.15 g g?1) at temperatures above 0 °C. We demonstrated that both fresh (0.15 g g?1 WC) and desiccated (0.07 g g?1 WC) seeds can be preserved at ?196 °C for at least 2 years.

Conclusions

Seed storage temperature and time of storage were statistically significant factors affecting seed storability. The presented data provide a foundation for the successful gene banking of P. nigra seeds.  相似文献   
48.
European Journal of Forest Research - Pterocarya fraxinifolia, native to the southern Caucasus and adjacent areas, has been widely introduced in Europe. In this study, we investigate the following:...  相似文献   
49.
The oxidation of linolenic acid (LNA) and soy lecithin was studied by differential scanning calorimetry (DSC) with linear programmed heating rates (non-isothermal mode). The interpretation of the shape of DSC curves is discussed, and it has been concluded that temperatures of the extrapolated start of heat release are the most reliable data for the rapid estimation of the oxidative stability of lipid materials. The Ozawa-Flynn-Wall method was used to calculate the kinetic parameters of the process: for LNA autoxidation the activation energy, Ea, and pre-exponential factor, Z, are 66 +/- 4 kJ/mol and 1.5 x 10(7) s(-1), respectively, and the autoxidation of lecithin is described by Ea = 98 +/- 6 kJ/mol and Z = 9.1 x 10(10) s(-1). Values of Ea and Z can be applied for calculation of the overall first-order rate constant of autoxidation at various temperatures, k(T). For the two studied lipids the comparison of k(T) values shows the inversion of their oxidative stabilities; that is, below 167 degrees C lecithin is more stable than LNA, k(T)lecithin < k(T)LNA, and above that temperature (termed the isokinetic temperature) k(T)lecithin > k(T)LNA. The calculated inversion of oxidative stabilities can be an explanation of similar observations for other pairs of lipids if the results of accelerated tests measured at temperatures above 100 degrees C are compared with the results obtained at temperatures below 100 degrees C.  相似文献   
50.
Mechanisms for Translocation of Heavy Metals from Soil to Epigeal Mosses   总被引:1,自引:0,他引:1  
The mechanisms for translocation of heavy metals from soil to epigeal mosses were investigated. The first mechanism was demonstrated for 137Cs and involved the uplifting of the pollutant-containing dust from the soil, followed by the local secondary deposition on surfaces of epigeal mosses and epiphytic lichens. The second mechanism involved the diffusion of metal cations from the soil through water wetting the moss into the gametophyte. The mechanism was demonstrated by measuring the electric conductance of wetted gametophytes with single ends immersed in solutions of Cu and Na salts. In addition, the concentrations of Cu and Cd were compared in moss samples exposed to the natural soil and to the soil contaminated with the metals. The exposition to the contaminated soil resulted in the statistically significant increase of metal concentrations in the gametophytes.  相似文献   
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