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91.
Kumud?B.?MishraEmail author Anamika?Mishra Kate?ina?Novotná Barbora?Rapantová Petra?Hodaňová Otmar?Urban Karel?Klem 《Plant methods》2016,12(1):46
Background
Non-invasive and high-throughput monitoring of drought in plants from its initiation to visible symptoms is essential to quest drought tolerant varieties. Among the existing methods, chlorophyll a fluorescence (ChlF) imaging has the potential to probe systematic changes in photosynthetic reactions; however, prerequisite of dark-adaptation limits its use for high-throughput screening.Results
To improve the throughput monitoring of plants, we have exploited their light-adaptive strategy, and investigated possibilities of measuring ChlF transients under low ambient irradiance. We found that the ChlF transients and associated parameters of two contrasting Arabidopsis thaliana accessions, Rsch and Co, give almost similar information, when measured either after ~20 min dark-adaptation or in the presence of half of the adaptive growth-irradiance. The fluorescence parameters, effective quantum yield of PSII photochemistry (ΦPSII) and fluorescence decrease ratio (R FD) resulting from this approach enabled us to differentiate accessions that is often not possible by well-established dark-adapted fluorescence parameter maximum quantum efficiency of PSII photochemistry (F V/F M). Further, we screened ChlF transients in rosettes of well-watered and drought-stressed six A. thaliana accessions, under half of the adaptive growth-irradiance, without any prior dark-adaptation. Relative water content (RWC) in leaves was also assayed and compared to the ChlF parameters. As expected, the RWC was significantly different in drought-stressed from that in well-watered plants in all the six investigated accessions on day-10 of induced drought; the maximum reduction in the RWC was obtained for Rsch (16%), whereas the minimum reduction was for Co (~7%). Drought induced changes were reflected in several features of ChlF transients; combinatorial images obtained from pattern recognition algorithms, trained on pixels of image sequence, improved the contrast among drought-stressed accessions, and the derived images were well-correlated with their RWC.Conclusions
We demonstrate here that ChlF transients and associated parameters measured even in the presence of low ambient irradiance preserved its features comparable to that of measured after dark-adaptation and discriminated the accessions having differential geographical origin; further, in combination with combinatorial image analysis tools, these data may be readily employed for early sensing and mapping effects of drought on plant’s physiology via easy and fully non-invasive means.92.
Patrick J Pollock Ronan Doyle Emma Tobin Kate Davison John Bainbridge 《Journal of zoo and wildlife medicine》2008,39(3):476-479
A 9-yr-old female Bornean orangutan (Pongo pygmaeus pygmaeus) presented with a 48-hr history of depression, lethargy, anorexia, and mucoid discharge from the rectum. Clinical, radiographic, and ultrasonographic examination demonstrated the presence of multiple distended loops of intestine, intestinal adhesions, and free gas within the abdomen. During exploratory laparotomy, fibrinopurulent diffuse peritonitis as a result of a ruptured intrapelvic abscess with associated large bowel adhesions was evident. The abdomen was thoroughly lavaged, necrotic debris and abscess wall removed, and fibrinous adhesions disrupted. The orangutan was kept sedated for 48 hr to allow for intensive care. Six months later, when the orangutan presented with similar clinical signs, ultrasonographic examination demonstrated the presence of a pelvic abscess. The previous procedure was repeated with the addition of a hysterectomy. This report is the first documentation of long-term management following surgical intervention for internal abdominal abscessation and septic peritonitis in a great ape. 相似文献
93.
94.
Evaluation of a new chest physiotherapy technique in dogs with airway fluid accumulation hospitalized in an intensive care unit 
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下载免费PDF全文 95.
Most agree that social and ecological approaches should be integrated to ensure sustainable management of natural resources. However, an analysis of the content of three problem-based journals shows that if social sciences are included at all, they are typically subservient to natural sciences, and that quantitative approaches are privileged. We argue that true integration is achievable only if natural sciences and social sciences are each robust and if they meet eye to eye. We call for more openness to stand-alone social science research in problem-based journals, especially to research using qualitative methods. We highlight the potential insights derived from studying decision makers at the microlevel: the pastoralists, farmers, ranchers, and foresters who make final management choices. We argue that publishing such qualitative social sciences promotes dialogue across disciplines, strengthens integration, and increases the real-world impact of research. 相似文献
96.
Joerg Henning Kate A. Henning Ngo Thanh Long Nguyen Truc Ha Le Tri Vu Joanne Meers 《Tropical animal health and production》2013,45(3):837-848
Ducks are considered to play a major role in the spread of highly pathogenic avian influenza (HPAI) H5N1 in Viet Nam, but detailed information on their management is limited. We distinguished two different systems (1) stationary duck flocks that are not commonly driven to rice fields beyond village boundaries and that are confined overnight on farms and (2) moving duck flocks that are intentionally driven to rice fields beyond village boundaries, that are not returning to home farms for extended periods and that are housed overnight in temporary enclosures in rice paddies. A total of 115 stationary and 22 moving flock farmers were interviewed in 2007 in the Mekong Delta of Viet Nam. Moving duck flocks are larger than stationary flocks, which is indicative of their more commercial production. Moving flock farmers apparently are more aware of HPAI risks than stationary flock farmers, as their flocks are more likely fully vaccinated and have less contact with chickens during scavenging. On the other hand, the spread of HPAI virus between birds might be promoted by moving duck flocks as they repeatedly use transport vehicles and numerous rice paddies for scavenging and are often visited by hatchery owners in the field for purchasing duck eggs. In addition, long distances travelled by moving duck flocks might also result in widespread dissemination of HPAI virus. Further studies are necessary to describe HPAI prevalence and travel patterns of moving duck flocks and to explore the moving duck flock network in detail. 相似文献
97.
98.
Nutrient cycling and distribution in different-aged plantations of Chinese fir in southern China 总被引：1，自引：0，他引：1
The distribution in tree biomass and understorey vegetation and annual biological and geochemical cycling of total nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) were measured in young, middle-aged and mature plantations (8-, 14- and 24-years old) of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) in southern China. Although >98% of nutrients occurred in the soil, soil nutrient content decreased with plantation age. Nutrient outputs from the soil exceeded inputs in stands of all ages but the net soil nutrient loss increased significantly for N, P and Ca with plantation age. Comparison of nutrient fluxes showed that the smallest (and hence limiting for nutrient cycling) fluxes were litter decomposition in the young plantation in contrast to canopy fluxes (apart from for Mg) in the middle-aged and mature plantations. Nutrient use efficiency, release of nutrients from litter decomposition and nutrient return, particularly in litterfall, increased significantly with plantation age. These results suggest that, as stand age increases, nutrient cycling in Chinese fir plantations is increasingly dominated by biological processes and becomes less dependent on external nutrient sources in rainfall and the soil. It therefore appears that prolonging the rotation length of Chinese fir plantations by approximately 5 years could be beneficial for maintaining the soil nutrient status for successive plantings. 相似文献
99.
Sue Aenishaenslin Kate Convery Basil Gua Mia Spain Lee Tunstall 《Small-Scale Forestry》2007,6(2):141-155
Private native forests in Australia perform a dual production and conservation role, providing an important source of timber,
and complementing formal conservation reserves. A comparison of policies for private native forests in New South Wales, Queensland,
Victoria and Tasmania illustrates the scope for timber harvesting, the provision for environmental values, and initiatives
for responsible and sustainable forest management. The sustainable management of Australia’s forests requires initiatives
by both government and landowners to accommodate changes in community attitudes, new management strategies, integrated catchment
management principles and both commercial and non-commercial opportunities for forest use. Of all of the Australian states,
New South Wales has the most restrictive laws in terms of forest management and harvesting. Queensland and Victorian legislation
have a more commercial focus, while Tasmania has a balance of both environmental and commercial objectives. The duty of care
for private native forests is a responsibility that falls to the landholder, and while this should be enforced by legislation,
the private provision of community benefits requires both recognition and reward. The presence or absence of incentives potentially
determines the effectiveness of forest codes of practice. 相似文献
100.
OBJECTIVE: To compare therapeutic feeding programme coverage for severely malnourished children achieved by a community-based therapeutic care (CTC) programme and a therapeutic feeding centre (TFC) programme operating in neighbouring districts in Malawi. DESIGN: Two surveys were implemented simultaneously one in each of the two programme areas. Each survey used a stratified design with strata defined using the centric systematic area sample method. Thirty 100 km2 quadrats were sampled. The community or communities located closest to the centre of each quadrat were sampled using a case-finding approach. Cases were defined as children aged under 5 years with 相似文献