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Adapting the global food and water models for analysis of SAT futures and development opportunities | Technical notes and exercises
2004
Shiferaw, Bekele (Bekele Ambaye) | Jayakumar, P. N.
Hydrogen Stable Isotope Analysis of Water Acquisition Ability of Deep Roots and Hydraulic Lift in Sixteen Food Crop Species Полный текст
2004
Walter Zegada-Lizarazu | Morio Iijima
Deep root penetration, which allows access to deep soil water and hydraulic lift, may help plants to overcome drought stress. The aim of this study was to evaluate the ability of sixteen food crop species to take up water from deep soil layers and the extent of hydraulic lift by the use of deuterated water. Plants were grown in pots consisting of two loose soil layers separated by a hardpan and a Vaseline layer. The lower (deep) layers were always kept wet (32%; ψ = –5 kPa), while soil moisture in the upper (topsoil) ones was adjusted to 25% (ψ = –7 kPa) and 12% (ψ = –120 kPa) in the well-watered and drought treatments, respectively. The deuterium labeling of the deep soil water provided evidence that wheat, Job’s tears, finger millet, soybean, barnyard millet, rice, and rye (in decreasing order of D2O increments) extracted more water from the deep layers under drought than well-watered in topsoil. These species showed significantly greater hydraulic lift under drought, except for soybean. Most of these species also showed increased root length density in deep soil layers and sustained high photosynthetic rates under drought. In contrast, pigeon pea, cowpea, common millet, pearl millet, foxtail millet, maize, barley, and oat did not show a significant increment in either deep-water uptake or hydraulic lift under drought. In summary, increased extraction of deep soil water under drought was closely related with the magnitude of hydraulic lift.
Показать больше [+] Меньше [-]Body lipids and adaptation of camel to food and water shortage: new data on adipocyte size and plasma leptin Полный текст
2004
Chilliard, Yves, | Bengoumi, M. | Delavaud, Carole | Faulconnier, Yannick | Faye, Bernard
Hydrogen stable isotope analysis of water acquisition ability of deep roots and hydraulic lift in sixteen food crop species
2004
Zegada-Lizarazu, W. (Nagoya Univ. (Japan)) | Iijima, M.
Deep root penetration, which allows access to deep soil water and hydraulic lift, may help plants to overcome drought stress. The aim of this study was to evaluate the ability of sixteen food crop species to take up water from deep soil layers and the extent of hydraulic lift by the use of deuterated water. Plants were grown in pots consisting of two loose soil layers separated by a hardpan and a Vaseline layer. The lower (deep) layers were always kept wet (32%; psi= -5 kPa), while soil moisture in the upper (topsoil) ones was adjusted to 25% (psi= -7 kPa) and 12% (psi= -120 kPa) in the well-watered and drought treatments, respectively. The deuterium labeling of the deep soil water provided evidence that wheat, Job's tears, finger millet, soybean, barnyard millet, rice, and rye (in decreasing order of D2O increments) extracted more water from the deep layers under drought than well-watered in topsoil. These species showed significantly greater hydraulic lift under drought, except for soybean. Most of these species also showed increased root length density in deep soil layers and sustained high photosynthetic rates under drought. In contrast, pigeon pea, cowpea, common millet, pearl millet, foxtail millet, maize, barley, and oat did not show a significant increment in either deep-water uptake or hydraulic lift under drought. In summary, increased extraction of deep soil water under drought was closely related with the magnitude of hydraulic lift.
Показать больше [+] Меньше [-]Antimicrobial effect of water extract of sumac (Rhus coriaria L.) on the growth of some food borne bacteria including pathogens
2004
Nasar-Abbas, S.M. | Halkman, A.K.
The antimicrobial effect of water extracts of sumac (Rhus coriaria L.) at concentrations of 0.1%, 0.5%, 1.0%, 2.5% and 5.0% (w/v), non-neutralized and after neutralization to pH 7.2 +/- 0.1, was studied on the growth of 12 bacterial strains (six Gram positive strains and six Gram negative strains), mostly food borne including pathogens. It was found to be effective against all the test organisms with Gram positive strains being more sensitive than Gram negative strains. Significant differences (P<0.01) were found among the bacteria and between the non-neutralized and neutralized extracts with non-neutralized being more effective against all the bacteria. The minimal inhibitory concentration (MIC) of the extract for each bacterial strain was studied by a gradient plate method. Among the Gram positive organisms, Bacillus species (Bacillus cereus, Bacillus megaterium, Bacillus subtilis, and Bacillus thuringiensis) were found to be the most sensitive showing MICs of 0.25-0.32% (after 24 h incubation) followed by Staphylococcus aureus (0.49%), while Listeria monocytogenes was found to be the least sensitive demonstrating a MIC of 0.67%. Of the Gram negative organisms, Salmonella enteritidis was found to be the most resistant with a MIC of 0.67% followed by Escherichia coli Type I, E. coli O157:H7, Proteus vulgaris and Hafnia alvei having MICs of 0.63%, 0.60%, 0.55% and 0.45%, respectively; whereas Citrobacter freundii was found to be the least resistant surviving up to 0.42%. Some loss of antimicrobial activity was, however, observed after incubation for 3 days. Bacteriostatic/bactericidal effects of sumac, as studied by enumerating survival by the viable count technique after 1 h direct contact of each microorganism with various concentrations of sumac extract, revealed a 4-5 log cycle reduction in Bacillus spp. and 2-3 log cycle reduction in other bacteria tested with 1.0% sumac extract.
Показать больше [+] Меньше [-]Transport properties of a high porosity model food at above and sub-freezing temperatures. 1. Thermophysical properties and water activity
2004
Hamdami, N. | Monteau, J.Y. | Le Bail, A.
Few data are available on the thermophysical properties of high porosity foodstuff in the freezing domain. This paper presents some data obtained with a cellulose sponge used as a model food. The fraction of unfreezable water was obtained from differential scanning calorimetry data, using two different methods with a very good agreement. Water activity was experimentally determined at positive temperature. Experimental data were modeled by the Guggenheim-Anderson-de Boer (GAB) model, and a model deduced from the Clausius-Clapeyron equation. The GAB model was used to extrapolate these data in the subzero domain. It showed a good agreement until a water activity of 0.9, whereas the second model is usable only up to the value of 0.75.
Показать больше [+] Меньше [-]IWRM: for sustainable use of water; 50 years of international experience with the concept of integrated water resources management; background document to the FAO/Netherlands conference on water for food an ecosystems, The Hague, 31 January - 5 February 2005
2004
Snellen, W.B. | Schrevel, A.
Since the concept was explained in detail at the Dublin Conference in 1992 (International Conference on Water and the Environment: Development Issues for the 21st Century), Integrated Water Resources Management has been at the core of thinking on water resource development. Today, integrated water resources management is seen as: “A process which promotes the coordinated development and management of water, land and related resources, in order to maximise the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems” (definition of IWRM, GWP 2000). This is a concise, yet precise definition of IWRM expressing the need for water development for socio-economic development, while keeping ecosystems healthy
Показать больше [+] Меньше [-]IWRM: for sustainable use of water; 50 years of international experience with the concept of integrated water resources management; background document to the FAO/Netherlands conference on water for food an ecosystems, The Hague, 31 January - 5 February 2005
2004
Snellen, W.B. | Schrevel, A.
Since the concept was explained in detail at the Dublin Conference in 1992 (International Conference on Water and the Environment: Development Issues for the 21st Century), Integrated Water Resources Management has been at the core of thinking on water resource development. Today, integrated water resources management is seen as: “A process which promotes the coordinated development and management of water, land and related resources, in order to maximise the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems” (definition of IWRM, GWP 2000). This is a concise, yet precise definition of IWRM expressing the need for water development for socio-economic development, while keeping ecosystems healthy
Показать больше [+] Меньше [-]Investigation of bisphenol a diglycidyl ether, bisphenol f diglycidyl ether and their hydroxy and chlorohydroxy derivatives stability in water-based food simulants Полный текст
2004
I. Poustková | J. Dobiáš | J. Poustka | M. Voldřich
Varnishes used as the inner coatings of food cans are often based on epoxy resins or vinylic organosols. The epoxy resins can be produced from bisphenol A (BPA) and bisphenol F (BPF) and they also contain bisphenol A diglycidyl ether (BADGE) of bisphenol F diglycidyl ether (BFDGE) as stabilising components. These compounds may break down during storage and also by influence of food simulants. The stability of BADGE and BFDGE was studied using reverse-phase gradient high performance liquid chromatography (RP-HPLC) with fluorescence detection (FLD). Four experiments were compared: (i) BPA solution at the concentration 3 μg/ml of each food simulant, (ii) BADGE solution at the concentration 3 μg/ml of each food simulant, (iii) BFDGE solution at the concentration 3 μg/ml of each food simulant and (iv) mixture of all bisphenols solution at the concentration 3 μg/ml of each food simulant. Distilled water, 10% ethanol, 95% ethanol and 3% acetic acid were used as food simulants. It was observed that BPA, BADGE and BFDGE were most stabile in 95% ethanol and least stabile in 3% acetic acid. Creation of hydroxy and chlorohydroxy derivatives was in each food simulant different so it cannot be predicted.
Показать больше [+] Меньше [-]Rapid Carbon Turnover During Growth of Atlantic Salmon (Salmo salar) Smolts in Sea Water, and Evidence for Reduced Food Consumption by Growth-Stunts Полный текст
2004
Jardine, T. D. (Timothy D.) | MacLatchy, Deborah L. | Fairchild, Wayne L. | Cunjak, Richard A. | Brown, Scott B.
Wild Atlantic salmon smolts were captured during spring out-migration in the Northwest Miramichi River, New Brunswick, Canada, and placed on an isotopically distinct hatchery diet to determine the relative contributions of growth and metabolic turnover to isotopic change. As expected for an ectothermic species, growth explained a large amount of isotopic variation in changing stable carbon ratios of muscle tissue (average r ²= 0.46) for the 3 years of study. Turnover rates of muscle carbon in all 3 years in growing fish (0.24–0.66 month⁻¹) were higher than previously reported values for other ectothermic species, but there was little evidence for isotopic change in non-growers (average r ²= 0.041, p > 0.1). It is unlikely that non-growers had consumed any of the hatchery diet over a 2-month period, thus preventing them from acquiring the new carbon isotopic signature. This period of food deprivation resulted in nitrogen-15 enrichment in liver relative to muscle (p= 0.003). It is advised that future isotope studies of metabolic turnover rates in ectotherms be conducted on slow-growing animals over a long time period. This would serve to avoid the obscuring effects of growth on isotopic change, and provide stronger comparisons to endothermic tissue turnover rates.
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