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1.
Journal of Plant Diseases and Protection - Factors influencing the sprouting ability of rhizome pieces of Calystegia sepium and root pieces of Convolvulus arvensis were analyzed in four...  相似文献   
2.
The investigations were carried out with 484 sows from two farms (farm A: housing the sows in small groups of 8 animals each, farm B with a large group of 100 sows) and a total number of 982 inseminations. The number of agonistic interactions was registered for each sow during 48 h after mixing soon after weaning the piglets at farm A. The individual rank place in the social hierarchy was calculated on the basis of wins and defeats and the sows were divided in high and low ranking sows. At farm B the rank position was estimated on the basis of the daily feeding order at two electronic feeding stations (first half of the sows in the feeding order = high ranking, second half = low ranking). Additionally, the following parameters were recorded for each sow: parity, genotype, farrowing rate and litter size (total and alive born piglets). The analysis showed that sows with a high rank position had a significantly higher farrowing rate (88.8%) compared to group-mates with low rank places (82.8%, p = 0.051) (farm A). Sows with a high rank position reached a significantly higher litter size of total born piglets (12.66, 16.14 piglets per litter respectively) than the low-ranking group-mates (12.13, 14.83 piglets/litter respectively — farms A and B). When mixing sows, the time and the conditions (e.g. group size, space allowance per sow) have to be considered to prevent the negative influence of low rank order on fertility.  相似文献   
3.
Urbanisation is an important driver of biodiversity loss, also contributing to habitat loss and fragmentation of grasslands at the urban-rural interface. While urban green spaces are known to include many grassland habitats, it is uncertain to what extent urban land use types harbour grasslands of special conservation interest and whether patch characteristics and connectivity of these differ from grasslands on agricultural land. By relating the city-wide biotope mapping to the land use mapping of Berlin, Germany, we assessed (1) to which specific urban land use types the major grassland biotope types belong, (2) differences in patch characteristics and connectivity, and (3) the conservation value of grassland patches at a typological level by means of their legal protection status. Grasslands cover 5% of Berlin's surface, and 43% of that area is assigned to legally protected grassland types. The majority of legally protected grassland (71%) lies on urban land opposed to 29% on agricultural land. Airports and historic parks, which only cover 2% of land in Berlin, contain one-third of all protected dry grasslands. Wet grassland is more confined to agricultural land. In airports and agricultural areas, grassland patches are larger but of a more complex shape than those in historic parks. In airports, grassland patches show greater connectivity as they are situated in grassland-dominated surroundings. Grassland in historic parks appears to be more vulnerable due to smaller patch sizes and higher fragmentation. The example of Berlin demonstrates that the urban green infrastructure can clearly contribute to grassland conservation and may thus partially compensate for the decline of traditional grasslands in cultural landscapes. It will be important to involve residents and landowners in urban grassland conservation and management because most grassland of special conservation interest (57%) was found outside of conservation areas.  相似文献   
4.

Context

Infectious diseases are important in the dynamics of many wildlife populations, but there is limited understanding of how landscape change influences susceptibility to disease.

Objectives

We aimed to quantify the time-delayed influence of spatial and temporal components of landscape change and climate variability on the prevalence of chlamydiosis in koala (Phascolarctos cinereus) populations in southeast Queensland, Australia.

Methods

We used data collected over 14 years (n = 9078 records) from a koala hospital along with time-lagged measures of landscape change and rainfall to conduct spatial and temporal analyses of the influence of landscape and environmental variables on prevalence of chlamydiosis and koala body condition.

Results

Areas with more suitable habitat were associated with higher levels of disease prevalence and better body condition, indicating that koalas were less likely to be impacted by chlamydiosis. More intact landscapes with higher proportions of total habitat are associated with a reduction in prevalence of chlamydiosis and a decrease in body condition. Increased annual rainfall contributed to a decrease in prevalence of chlamydiosis and an increase in body condition. Urbanization was associated with an increase in disease, however the effects of urban landscape change and climate variability on chlamydiosis may not manifest until several years later when overt disease impacts the population via effects upon body condition and reproductive success.

Conclusions

Our study highlights the importance of effects of landscape change and climate variability on disease prevalence in wildlife. This recognition is essential for long-term conservation planning, especially as disease often interacts with other threats.
  相似文献   
5.
The epistomatal wax crystalloids of potted spruce plants exposed for 20 weeks to motor vehicle emissions along roadside and in a fumigation chamber were studied in the scanning electron microscope. An accelerated structural degradation of the wax crystalloids was observed in comparison with control plants. This structural degradation is considered to cause a structural obstruction of the stomatal antechambers and to contribute to the observed reduction of gas exchange.  相似文献   
6.
Doppler spectra of the abdominal aorta (AAo), cranial mesenteric artery (CMA), celiac artery (CA), and left renal artery (LRA) were obtained from 11 fasted, clinically healthy, conscious Beagles before and after inducing severe acute normovolemic anemia (mean±standard deviation hematocrit 16.0±0.77%). Peak systolic, end diastolic, and time-averaged mean velocities were measured. The different vessels were compared with each other. Peak systolic velocity ratio and time-averaged mean velocity ratio of splanchnic vessels to corresponding variables of the AAo were computed and compared between and within vessels during physiologic and anemic states. There was no difference between LRA and AAo, CMA or CA regarding time-averaged mean velocity, time-averaged mean velocity ratio, or end diastolic velocity during the physiological state. During the anemic state, LRA mean time-averaged mean velocity ( P ≤0.008) and mean end diastolic velocity ( P ≤0.041) were significantly lower than those of AAo, CMA, and CA. Mean time-averaged mean velocity ratio of the LRA was also significantly ( P ≤0.004) lower than the CMA and CA ratios, and significantly ( P =0.014) lower during anemic state than physiologic state of the same vessel. End diastolic and time-averaged mean velocities of the AAo, CMA, and CA increased proportionally during anemia, but there was a relatively less increase in the same variables of the LRA, suggesting less increase in blood flow. Doppler ratios allowed a noninvasive comparison between splanchnic and aortic hemodynamics. Velocity ratios might be useful for clinical detection of relative hemodynamic changes between different vessels.  相似文献   
7.
Plant sterols such as sitosterol and campesterol are frequently applied as functional food in the prevention of atherosclerosis. Recently, it became clear that plasma derived plant sterols accumulate in murine brains. We questioned whether plant sterols in the brain are associated with alterations in brain cholesterol homeostasis and subsequently with brain functions. ATP binding cassette (Abc)g5-/- mice, a phytosterolemia model, were compared to Abcg5+/+ mice for serum and brain plant sterol accumulation and behavioral and cognitive performance. Serum and brain plant sterol concentrations were respectively 35-70-fold and 5-12-fold increased in Abcg5-/- mice (P<0.001). Plant sterol accumulation resulted in decreased levels of desmosterol (P<0.01) and 24(S)-hydroxycholesterol (P<0.01) in the hippocampus, the brain region important for learning and memory functions, and increased lanosterol levels (P<0.01) in the cortex. However, Abcg5-/- and Abcg5+/+ displayed no differences in memory functions or in anxiety and mood related behavior. The swimming speed of the Abcg5-/- mice was slightly higher compared to Abcg5+/+ mice (P<0.001). In conclusion, plant sterols in the brains of Abcg5-/- mice did have consequences for brain cholesterol metabolism, but did not lead to an overt phenotype of memory or anxiety related behavior. Thus, our data provide no contra-indication for nutritional intake of plant sterol enriched nutrition.  相似文献   
8.
 The Bradford protein quantification assay is based on an absorbance shift in Coomassie brilliant blue G-250 (CBB). Samples extracted for glomalin, a protein produced by arbuscular mycorrhizal (AM) fungi, are quantified using the Bradford assay. CBB is known to react with polyphenolic substances, and co-extraction of glomalin and humic substances is known to occur. The effects of increasing concentrations polyphenolic compounds were measured. The addition of any amount of polyphenolic compounds increased the Bradford reactive fraction (BRF) of soil extract. Caution is required when interpreting BRF data, as comparison of BRF data from different studies or different field sites is problematic. The BRF may represent recalcitrant organic material in soil, though its relationship to AM fungi remains unclear.  相似文献   
9.
Periventricular nodular heterotopia is a common neuronal malformation in humans, often leading to epilepsy and other neurologic diseases. A 2-month-old female Chihuahua weighing 750 g was examined because of a history of epileptic seizures and abnormalities in gait and behavior. Results of the clinical examination were consistent with a multifocal neurologic disease with localization in the forebrain and spinovestibular system. The magnetic resonance imaging showed multiple bilateral periventricular nodules isointense to gray matter and ventriculomegaly. Histopathological and immunohistological examination of the brain revealed that periventricular nodules consisted of neurons, fewer astrocytes, and some oligodendroglia consistent with periventricular nodular heterotopias.  相似文献   
10.
European Journal of Plant Pathology - In total 58 Xanthomonas strains isolated from Araceae worldwide, together with 13 other phylogenetically-related Xanthomonas strains, were characterized using...  相似文献   
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