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331.
Jana Spilková 《Agriculture and Human Values》2017,34(4):887-897
This paper aims to fill the gap in literature concerning community gardens in post-communist countries by focusing on the situation in Prague, Czechia. It introduces Prague′s newly emerged community gardens and presents the results of a first representative survey of these gardens. Information was gathered about eleven of the sixteen larger community gardens and the data were collected by semi-structured interviews with the managers of the particular gardens. The paper compares the Czech community gardens as representatives of civic agriculture forms in post-communist countries with their counterparts (mainly those in the North America) and stresses their similarities and differences. The results show that the new community gardens reflect much of what can be seen elsewhere in terms of spatial and organizational design, as well as reasons for starting them, motivations for participation and some of the challenges experienced. However, in contrast to many community gardens in the USA, Canada and UK that focus on food and nutrition provision, in Prague the community is more of a priority than food and the other mentioned benefits. The paper shows that different activities, events and functions make gardens important hubs of their communities and potential tools of further community involvement and social change. 相似文献
332.
COMPUTED TOMOGRAPHIC CHARACTERISTICS OF THE THYROID GLANDS IN EIGHT HYPERTHYROID CATS PRE‐ AND POSTMETHIMAZOLE TREATMENT COMPARED WITH SEVEN EUTHYROID CATS
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Jennifer L. Bush Sarah Nemanic Jana Gordon Gerd Bobe 《Veterinary radiology & ultrasound》2017,58(2):176-185
Hyperthyroidism is the most common feline endocrinopathy; thyroid computed tomography (CT) may improve disease detection and methimazole dose selection. Objectives of this experimental pre‐post with historical case‐control study were to perform thyroid CT imaging in awake or mildly sedated hyperthyroid cats, compare thyroid gland CT appearance in euthyroid and hyperthyroid cats pre‐ and postmethimazole treatment, and determine whether thyroid size or attenuation correlate with methimazole dose needed for euthyroidism. Premethimazole treatment, eight hyperthyroid cats received CT scans from the head to heart, which were compared to CT of seven euthyroid cats. Total thyroxine levels were monitored every 3–4 weeks. Postmethimazole CT was performed 30 days after achieving euthyroid status. Computed tomography parameters recorded included thyroid length, width, height, attenuation, and heterogeneity. Median time between CT was 70 days (53–213 days). Mild sedation was needed in five hyperthyroid cats premethimazole, and none postmethimazole. Thyroid volume was significantly larger in hyperthyroid cats compared to euthyroid cats (785.0 mm3 vs. 154.9 mm3; P = 0.002) and remained unchanged by methimazole treatment (?4.5 mm3; P = 0.50). Thyroid attenuation and heterogeneity decreased with methimazole treatment (96.1 HU vs. 85.9 HU; P = 0.02. 12.4 HU vs. 8.1 HU; P = 0.009). Methimazole dose ranged from 2.5 to 10 mg daily with a positive correlation between pretreatment thyroid gland volume and dose needed to achieve euthyroidism (P = 0.03). Euthyroid and hyperthyroid cats are easily imaged awake or mildly sedated with CT. Methimazole in hyperthyroid cats significantly lowers thyroid attenuation and heterogeneity, but not size. 相似文献
333.
Jessica S. Wong Adam C. Cave Danielle M. Lightle Walter F. Mahaffee Steve E. Naranjo Nik G. Wiman J. Megan Woltz Jana C. Lee 《Journal of pest science》2018,91(4):1269-1278
Drosophila suzukii is widely studied because of its status as a global pest of berries and soft fruits. Environmental conditions and access to food resources impact the physiology and fitness of D. suzukii; these factors could also affect dispersal. Flight mills are a convenient tool for measuring and comparing the flight performance of insects. In this study, two experiments examined the effects of diet and humidity on D. suzukii flight performance using custom-built flight mills, and a third experiment compared the energy reserves of D. suzukii flown or not flown on flight mills. Over all flight assays, the median flight distance and duration were 27.16 m and 2.37 min, respectively, and the mean flight velocity was 0.18 m/s. The maximum flight distance and duration by an individual were 1.75 km and 2.35 h, respectively. Drosophila suzukii provisioned with blossoms, fruits, or standard laboratory diets flew farther distances and longer durations than starved flies. While starvation was associated with reduced flight performance, there were no observed differences between diet types. It remains unclear whether D. suzukii consistently use lipids, glycogen, sugar, or another energy source for flight because tethered individuals may not have flown enough to deplete energy reserves. Humidity did not affect flight performance of D. suzukii within a?~?2 h test period. These data indicate that most D. suzukii are likely to remain within limited area (e.g., within a field) but that some individuals can disperse long distances (field to field spread). 相似文献
334.
Iodine is an essential trace element for humans, and while plants play an important role in its supplementation, they can also be subject to iodine toxicity. Herein, comparison of iodide and iodate effects on barley (Hordeum vulgare L.) development was evaluated in laboratory experiments when it was cultivated in iodine-spiked agar cultivation media and agricultural soil. Our results show that iodine toxicity is highly dependent on its chemical form and also reflects growth substrate type. Barley responses to iodine presence in agar and soil media suggest that iodide has more severe inhibitory effects than iodate on plant growth. Furthermore, the detrimental effect of iodine notably increased in soil with biomass synthesis as the most sensitive physiological parameter to adverse iodide and iodate effects. However, mild iodate and iodide stimulation of barley growth was observed which implies they are beneficial for growth at low concentrations. These effects were more intense when iodine was applied as iodide, especially in soil cultivation system where natural geochemical processes lead to alteration in iodine speciation which significantly increases plant sensitivity to iodine toxicity. 相似文献
335.
Fleur Longuetaud Frédéric Mothe Philippe Santenoise Ndiaye Diop Jana Dlouha Meriem Fournier Christine Deleuze 《Annals of Forest Science》2017,74(3):64
? Key message
Intensive measurements of basic specific gravity and relative water content of lumens show that within-stem variations strongly depend on species and cannot be summarised through the typical patterns reported in the literature; breast height measurements are not always representative of the whole stem.? Context
Knowledge of the distribution of wood properties within the tree is essential for understanding tree physiology as well as for biomass estimations and for assessing the quality of wood products.? Aims
The radial and vertical variations of basic specific gravity (BSG) and relative water content of lumens (RWC L ) were studied for five species: Quercus petraea/robur, Fagus sylvatica, Acer pseudoplatanus, Abies alba and Pseudotsuga menziesii. The observations were compared with typical patterns of variations reported in the literature.? Methods
Wood discs were sampled regularly along tree stems and X-rayed in their fresh and oven-dry states.? Results
At breast height, BSG was found to clearly increase radially (pith to bark) for two species and to decrease for one species. For F. sylvatica and A. alba, the radial variations of BSG were rather U-shaped, with in particular inner wood areas showing respectively lower and higher BSG than the corresponding mature wood. RWC L increased generally from inner to outer area but wet sapwood was clearly distinguishable only for the coniferous species. Vertical variations of BSG and RWC L were strongly dependant on the species with usually non-linear patterns.? Conclusion
The observed variations of BSG were only partially in agreement with the reported typical radial patterns. Despite the vertical variations, the mean BSG of a cross-section at breast height appeared to be a good estimator of the mean BSG of the whole stem (although the difference was statistically significant for coniferous species), whereas breast height measurement of RWC L was not representative of the whole stem.336.
Aditi Jana Sonali Sinha Manivannan Jothiramajayam Anish Nag 《Archives of Agronomy and Soil Science》2017,63(10):1443-1453
Leaching of heavy metals from coal fly ash dumpsites is an environmental threat often polluting both groundwater and surface water. This led to a detailed investigation on the cyto-genotoxicity and oxidative stress associated with the fly ash leachate (FL). Allium cepa L. bulbs were exposed to three concentrations of FL. Response to FL resulted in a reduction of root growth, inhibition of cell viability by up to 50%, and decrease in mitotic indices (control: 10.27; FA:water 1:4–4.52) with increased frequency of chromosome aberrations (5.7 fold) and bi-nucleate cells. Results of comet assay indicated that approximately sixfold increase in genotoxicity of FL was congruent with the endpoints of oxidative stress evaluated. The malondialdehyde content, superoxide dismutase, guaiacol peroxidase and glutathione-S-transferase activities were elevated in the treated plants in a dose dependent manner. The elemental analysis of FL showed the presence of heavy metals like cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), cadmium (Cd), nickel (Ni), lead (Pb) and zinc (Zn). The study demonstrated that FL can cause adverse effects to the plants. Therefore, the disposal of coal fly ash should be handled with caution and prevented from contaminating the surroundings. 相似文献