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The isolation of (+)-totarol as active compound against Mycobacterium tuberculosis is reported from Chamaecyparis nootkatensis outerbark. 相似文献
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Kate L. Constantine Fernadis Makale Idah Mugambi Duncan Chacha Harrison Rware Alexander Muvea Vincent K. Kipngetich Justice Tambo Adewale Ogunmodede Djami Djeddour Corin F. Pratt Ivan Rwomushana Frances Williams 《Pest management science》2023,79(11):4343-4356
Background
In Kenya, rice (Oryza sativa L.) is mainly produced under irrigation by small-scale farmers. Mwea irrigation scheme (MIS) in Kirinyaga County accounts for 80–88% of rice production. Here, rice is the main source of livelihood and a source of revenue generation for the county. However, a recently established invasive freshwater snail, Pomacea canaliculata (Lamarck) (family: Ampullariidae), a species of apple snail, presents a serious threat to rice production.Results
Household surveys, focus group discussions and key informant interviews highlight apple snail as a serious problem in MIS. Households that observed at least a moderate level of infestation (>20% of cultivated area) experienced significant reductions in rice yield (~14%) and net rice income (~60%). Farmers reported increased use of chemical pesticides for management of apple snail. In addition, the cost of hired labor for physical removal of egg masses and snails is resulting in substantial negative effects on net income. Farmer age, area of land owned, responsibility for decision-making, receipt of extension advice, training, and membership of a farmer organization, were all statistically significant variables to explain farmers awareness of the need for area-wide apple snail management.Conclusion
Strategies to limit the spread of apple snail are urgently needed. A Multi-Institutional Technical Team (MITT) has been established to spearhead management efforts and consolidate advice to farmers on how to manage apple snail. However, without action to mitigate spread, the consequences could be disastrous for rice production and food security in Kenya, and for other rice growing regions across Africa. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献3.
Peter A. Roussos Aristidis Matsoukis Constantine A. Pontikis Aikaterini Chronopoulou-Sereli 《Scientia Horticulturae》2007
Possible correlations among several environmental factors and the internal phenol content and oxidative enzyme activities of olive explants were examined. The statistic analysis revealed that the same environmental factor exhibited different relation with the various individual phenolic compounds found in explants and the oxidative enzyme activities. The major contribution of air temperature, total radiation, soil temperature at a depth of 25 cm and photoperiod on the explant phenol content and on the oxidative enzyme activities has been revealed. These environmental factors exhibited the highest number of significant relationships with the measured variables. 相似文献
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Leena Riekkola Virginia Andrews‐Goff Ari Friedlaender Alexandre N. Zerbini Rochelle Constantine 《水产资源保护:海洋与淡水生态系统》2020,30(5):937-948
- Long‐distance migration is a demanding physical activity, and how well animals manage the associated costs will have important implications for their fitness.
- The Oceania humpback whale (Megaptera novaeangliae) population is recovering from past exploitation markedly slower than the neighbouring east Australian whales. The reasons for this are unknown, although higher energetic costs of longer migratory distances could be a possible explanation. Due to their fully aquatic lives, studying the energy expenditure of these large animals requires methods that do not rely on capturing the animal, such as bioenergetic models.
- A state‐space model was fitted to satellite data to infer behavioural states for southern migrating whales. Travel speeds and behavioural states were used in a bioenergetic model to estimate the energetic cost of the migration phase. Relative differences in average duration, distance, and energetic costs were compared between migratory routes and distances.
- Total energy used during migration was a trade‐off between cost of transport (determined by travel speed) and daily maintenance (determined by daily basal metabolic costs). Oceania whales migrating to the Amundsen and Bellingshausen Seas travelled fastest and furthest, 15 and 21% further than whales migrating to the d'Urville Sea (east Australian whales) and Ross Sea, respectively. Therefore, they had the highest cost of transport, 25 and 85% higher than for d'Urville Sea and Ross Sea whales, respectively. However, energy saved in terms of daily maintenance by using fewer days to complete a longer migration resulted in only a 6–7% increase in total energetic cost.
- The results highlight that travelling further does not necessarily translate into an increase in total energy expenditure for migratory whales, since they can compensate for longer distance by travelling faster. Further research on the energetics of different whale populations could provide insight into the productivity of Southern Ocean feeding regions and help understand the environmental and anthropogenic effects on the whales' energy budgets.
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Rabies virus in nasal mucosa of naturally infected bats 总被引：2，自引：0，他引：2
Rabies virus was demonstrated in the olfactory mucosa of naturally infected bats by staining with fluorescent antibody and by isolation of the virus from the nasal tissues. The olfactory mucosa is a potential portal of entry and exit for airborne rabies virus in bat caves. 相似文献
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Scherer SW Cheung J MacDonald JR Osborne LR Nakabayashi K Herbrick JA Carson AR Parker-Katiraee L Skaug J Khaja R Zhang J Hudek AK Li M Haddad M Duggan GE Fernandez BA Kanematsu E Gentles S Christopoulos CC Choufani S Kwasnicka D Zheng XH Lai Z Nusskern D Zhang Q Gu Z Lu F Zeesman S Nowaczyk MJ Teshima I Chitayat D Shuman C Weksberg R Zackai EH Grebe TA Cox SR Kirkpatrick SJ Rahman N Friedman JM Heng HH Pelicci PG Lo-Coco F Belloni E Shaffer LG Pober B Morton CC Gusella JF Bruns GA Korf BR 《Science (New York, N.Y.)》2003,300(5620):767-772
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OBJECTIVE: To assess the Ca, nutrient and food intake of Greek Orthodox Christian monks during a vegetarian-type fasting week, compared with their normal diet. DESIGN: Dietary data collection (using 7 d weighed food records), anthropometric and blood pressure measurements, as well as serum glucose and lipid analyses, were performed during Palm Sunday week (fasting) and the week following Pentecost Sunday (non-fasting). Mean daily nutrient and food (g/d) intakes were calculated from the food records. SETTING: The study took place in two monasteries in the Municipality of Heraklion, Crete. SUBJECTS: The study involved ten healthy monks aged 254 (sd 10June 2005. RESULTS: Nutrient and food intake profiles were more favourable during the fasting week, when participants had lower intakes of total and saturated fat and trans-fatty acids, and higher intakes of dietary fibre, Fe, folate, legumes and fish/seafood. Ca intake was lower when participants fasted, whereas consumption of dairy products, meat and eggs increased significantly in the non-fasting week. Systolic blood pressure was significantly higher, whereas blood lipid levels were more favourable during the fasting week. CONCLUSIONS: The periodic vegetarianism recommended by the Greek Orthodox Church contributes to the favourable profiles of several biomarkers of health among this sample of monks. The fasting rituals described are an important component of the traditional diet of Crete and should be emphasised in nutrition education programmes promoting this Mediterranean eating pattern. 相似文献
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Studies on genetic variability in Trypanosoma evansi have been limited by a lack of high-resolution techniques. In this study, we have investigated the use of inter-simple sequence repeats (ISSR) and microsatellites in revealing polymorphism among T. evansi isolates. Twelve ISSR primers and five microsatellite loci were used to generate polymorphic bands and alleles, respectively, to investigate the genetic variability among T. evansi isolates from Africa and Asia. Seven of the twelve ISSR primers showed variability between isolates with a total of 71 fragments of which 49(69%) were polymorphic. Microsatellite analysis revealed a total of 60 alleles. On average the ISSR markers revealed a higher genetic diversity (23%) than microsatellites (21.1%). The two techniques showed a strong agreement of r=0.95 for Dice and r=0.91 for Jaccard indices in estimating the genetic distances between isolates. The distance UPGMA tree revealed two major clusters of T. evansi which correlate with the minicircle classification of subtype A and B. The cophenetic correlation coefficient between Dice and Jaccard based matrices were r=0.79 for microsatellites and r=0.73 for ISSR indicating a strong agreement between dendrograms. The results suggest that both ISSR and microsatellites markers are useful in detecting genetic variability within T. evansi. 相似文献