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Undulations in weather patterns have caused climate shifts of increased frequency and duration around the world. The need for additional research and model data on this pressing problem has resulted in a plethora of research groups examining a particular tree species or biome for negative effects of climate change. This review aims to (1) collect and merge recent research data on regeneration within old- and new-growth forests, (2) highlight and expand upon selected topics for additional discussion, and (3) report how shade tolerance, drought toler- ance, and inherent plasticity affect tree growth and development. Al- though shade and drought tolerance have been well studied by a number of research groups, this review reveals that in-depth analysis of a single or a few species in a given area will not generate the data required to implement a successful regeneration plan. Studies using historical accounts of previous species composition, information regarding site sea- sonality, species competition, and individual responses to drought and shade are needed to (1) develop best management plans and (2) ensure future modeling experiments are focused on a greater variety of species using more innovative methods to evaluate climate change effects. 相似文献
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John M David Sandra Duarte Vogel Kimberly Longo Daniel Sanchez Gregory Lawson 《Veterinary anaesthesia and analgesia》2014,41(6):654-659
ObjectiveTo investigate a topical local anesthesia technique as a means to prevent and/or diminish pain in mice in a laboratory setting associated with tail vein injections performed by personnel in training.Study designProspective, randomized experimental trial.AnimalsThirty six adult female, 23–28 g CD-1 mice from an in-house training colony. They were acclimated to routine training and handling classes.MethodsEutectic mixture of local anesthetics (EMLA) cream (2.5% lidocaine/2.5% prilocaine) or a bland ointment control (n = 18) was applied on the tail prior to intravenous injection. The injections were performed by novices, who had never attempted the procedure, and experienced personnel. All participants were blinded to treatment groups. Three injection attempts were allowed per animal. The mice were observed and scored by blinded evaluators for behavioral and physiological changes, including respiratory rate, vocalization, tail flick, and escape behaviors, during and after the injection.ResultsThis study demonstrates that aversive behaviors induced by lateral tail vein injection were not changed by the preemptive application of EMLA cream. The aversive behaviors associated with lateral tail vein injection were significantly affected by the number of injection attempts and the individual's experience level.Conclusions and clinical relevanceTopical EMLA cream did not reduce signs of aversive reaction to tail vein injection and thus we did not find support for its use in mouse training programs for tail vein injections. 相似文献
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Considerable research has been done in an attempt to utilize solar energy to improve the productivity of aquatic culture systems. At the same time solar energy research has identified energy storage as a problem in commercializing the use of solar energy for heating and other purposes. Thus, a system is proposed to combine aquacultural production facilities and solar energy storage with the possibility of later combining recycling of agricultural wastes into the combined system. System feasibility is being explored by use of mathematical simulation models. Six model components on interacting models are briefly outlined and progress on detailed model development is described. A model capable of predicting the hourly solar energy available at any point on the earth's surface for which cloud cover, clearness number and latitude are known, is described. Example model output is presented and compared to measured data. 相似文献
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K F Lawson H Chiu S J Crosgrey M Matson G A Casey J B Campbell 《Canadian journal of veterinary research》1997,61(1):39-42
Red foxes (Vulpes vulpes) vaccinated orally with the ERA strain of rabies vaccine in a bait were challenged after 83 mo. Ten of 11 foxes that had seroconverted following vaccination resisted challenge with a virulent rabies virus which produced clinical signs of rabies in 6 of 6 unvaccinated foxes. Five of 11 vaccinated animals retained titers of rabies virus neutralizing antibody throughout the period. Although 6 of 11 had no detectable antibody at the time of challenge, 5 of these 6 resisted challenge and had an anamnestic response, as indicated by elevated titers of antibody when measured at day 77 postchallenge. These results show that foxes can be immunized successfully with a single oral dose of ERA vaccine, probably with protection against a lethal rabies challenge, for at least 7 y. 相似文献
16.
V. Vorne K. Ojanper L. De Temmerman M. Bindi P. Hgy M. B. Jones T. Lawson K. Persson 《European Journal of Agronomy》2002,17(4):369-381
Potato (Solanum tuberosum L cv. Bintje) was exposed to ambient and elevated carbon dioxide (CO2), to ambient and elevated ozone (O3) and to elevated levels of both gases during two growing seasons, 1998 and 1999. Experiments in open-top chambers (OTC) were carried out in Finland, Sweden, Ireland, United Kingdom, Germany and Belgium and a FACE (Free Air Carbon dioxide Enrichment) experiment was carried out in Italy. In OTCs the plants were grown under ambient CO2 concentrations or with 550 and 680 μl l−1 CO2 alone or in combination with ambient or elevated O3 concentrations (target seasonal mean of 60 nl l−1 8 h per day). In the FACE systems the plants were exposed to ambient or 550 μl l−1 CO2. In the OTC experiments the reducing sugar content of potato tubers decreased significantly with increased concentration of O3. The starch content of potato tubers decreased, with negative impact on tuber quality, but the ascorbic acid concentration increased as a function of the AOT40 (The sum of the differences between hourly ozone concentration and 40 nl l−1 for each hour when the concentration exceeds 40 nl l−1 during a relevant growing season). However, simultaneous exposure to elevated CO2 counteracted the ozone effect. With increase in the CO2 exposure, glycoalkaloid and nitrate concentrations decreased yielding improved quality, while the citric acid concentration decreased causing a higher risk for discoloration after cooking. The amount of dry matter and starch increased significantly in the FACE experiment. 相似文献
17.
Demographic, familial and trait predictors of fruit and vegetable consumption by pre-school children 总被引:6,自引:0,他引:6
Cooke LJ Wardle J Gibson EL Sapochnik M Sheiham A Lawson M 《Public health nutrition》2004,7(2):295-302
OBJECTIVE: To examine the contribution to fruit and vegetable eating in children of potential predictive variables within the domains of demographics, parental feeding practices and personality traits. DESIGN: Cross-sectional survey. SETTING: Questionnaires were distributed to parents through 22 London nursery schools. SUBJECTS: Questionnaires were completed and returned by 564 parents or principal caregivers of 2-6-year-old children. RESULTS: Significant predictors of children's fruit and vegetable intake emerged from all three domains examined. Demographic variables associated with child's vegetable consumption were mother's education and child's age and gender. Only ethnicity was significantly associated with fruit consumption. Parental consumption, breast-feeding and early introduction to fruit and vegetables were related to intake of both. Family meal times were associated with higher intake of vegetables, but not of fruit. Two characteristics of children themselves (food neophobia and enjoyment of food) were strongly related to the consumption of fruit and vegetables. Subsequent multivariate analyses revealed that parental intake and child food neophobia independently predicted intake of both foods. In the presence of these, fruit consumption was affected by breast-feeding and early introduction to fruit, whereas vegetable consumption was related only to child's gender and enjoyment of food. CONCLUSIONS: These findings may be used to inform future interventions aimed at increasing children's consumption of fruit and vegetables. Parents should be made aware of the possible impact of their own behaviour on the eating habits of their children. 相似文献
18.
Lawson AC 《Science (New York, N.Y.)》1940,92(2382):162-164
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