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Water scarcity in relation to food security and sustainable use of biodiversity in Jordan
2005
Al-Eisawi, D.M.H.,University of Jordan, Amman (Jordan). Fac. of Science
In Jordan, the only fresh water ecosystem Azraq Wetland Oasis was destroyed due to water scarcity. The destruction was a result of water over pumping from the greater basaltic Azraq basin. Hundreds of artesian wells have been drilled during the past two to three decades. This excessive drainage of water has lead to total dryness of the Azraq Oasis except from two ponds where water is pumped daily into them. This drainage of water has lead to disappearance of the vegetation where 135 species have been recorded in that site. Most farms in the area have been destroyed and deserted. Azraq Oasis used to be an attractive site for tourism affected the socioeconomic integrity of the people living in that area. Another sad case is that the use of the treated waste water in irrigation as about 50 million cubic meters are added to the water of the Zarqa River ending the King Talal Dam.
Показать больше [+] Меньше [-]Measurement of water movement in food and biomaterials by pulsed field gradient (PFG)-NMR
2005
Hong, Y.P.(Korea Univ., Seoul (Korea R.)) | Lee, C.H.
Pulsed-field gradient NMR (PFG -NMR) is widely applied to probe living tissues and biological cells structure for measuring thermodynamic binding constants, membrane permeability and rates of transmembrane exchange processes. Water movements in biological systems and food matrices are important in the engineering aspect such as quality manipulation in food processing. The measurement of diffusion properties of water molecules in food systems is now possible using PFG -NMR, and the hydration properties and hydrodynamic properties of food materials can be accurately evaluated by this method. In this paper, we measured the diffusion behavior of water in protein matrix, Tofu, and the membrane permeability in biological cell such as chlorella, yeast and human red blood cell non-invasively by PFG-NMR.
Показать больше [+] Меньше [-]Water consumption by rusa deer (Cervus timorensis) stags as influenced by different types of food
2005
Kii, W.Y. | Dryden, G.M.
During winter in southern Queensland, eight rusa deer stags aged 4 years were given ad libitum lucerne (Medicago sativa) hay and confined in individual metabolism pens for 26 days. Stags ate 2.04 kg dry matter (DM) per day and drank 6.4 kg water per day, while the drinking water : food DM ratio was 3.3 l/kg. In experiment 2, seven rusa stags were given ad libitum lucerne hay or oaten (Avena spp.) hay with or without barley grain supplementation (200 g/day) for 56 days (four periods). This experiment was conducted from 26 July to 19 September 2001, when the stags were exhibiting the behaviour characteristic of the rut. Rusa stags ate 1.19 and 1.17 kg DM per day of lucerne and oaten hay respectively. Rusa stags given oaten hay drank slightly more water than those that received lucerne hay (5.34 and 4.47 kg/day, respectively). The drinking water : food DM ratios were 3.81 and 4.67 kg/kg for lucerne and oaten hay, respectively. Barley grain supplementation (200 g/day) had no influence on total food or water intakes of the rusa stags.
Показать больше [+] Меньше [-]Wastewater as a non-traditional source of livelihoods, city food security and water for agriculture
2005
Raschid-Sally, Liqa | Abayawardana, Sarath
Application of guar gum as a flocculant aid in food processing and potable water treatment Полный текст
2005
Sen Gupta, Bhaskar | Ako, Jubilant E.
Guar gum is a widely used ingredient in food processing industry. This work highlights the use of guar gum as a flocculant aid in potable water treatment. Current practice of using synthetic flocculants such as polyacryl-amide has raised controversies of acrylamide residues in water and thereby increasing health risk of the population. The flocculating effect of guar gum on the settling characteristics of flocs in a bench-scale potable water clarification process is presented in this work. Data from two experimental runs, namely, run A (guar gum and primary coagulant) and run B (primary coagulant only), were used to plot settling velocity distribution curves (SVDC). Observation of these curves revealed that guar gum increased the proportion of destabilised colloidal impurities settling above a stated minimum velocity. It was found that guar gum may be used along with alum to reduce raw water turbidity from 26.5 to 1.0. It may be concluded that guar gum can be used as a safer alternative to polyacrylamide in water treatment for drinking or food processing purposes.
Показать больше [+] Меньше [-]Modelling of simultaneous two-sided migration into water and olive oil from nylon food packaging Полный текст
2005
Stoffers, Niels H. | Dekker, Matthijs | Linssen, Jozef P. H. | Störmer, Angela | Franz, Roland | van Boekel, Martinus A. J. S.
Nylon 6 and nylon 12 food packaging materials used as sausage casings are typically exposed to fatty food on one side and boiling water on the other during the cooking process. To simulate the migration behaviour under these conditions, a special migration cell was constructed and filled with olive oil on one side of the polymer and water on the other to find out what amounts of the migrants will transfer to either side and phase at 100 °C. Results show that when a nylon 6 film is exposed to the conditions as described above, total mass transfer of the monomer—caprolactam—into the water phase occurs after 2 h at 100 °C. Nylon 12 sausage casings release similar amounts of their monomer—laurolactam—into both the aqueous and oil phase. An existing computer migration model was adapted to simulate the situation of simultaneous two-sided migration applying previously determined diffusion and partitioning coefficients. The suitability of the model was confirmed by experimental data.
Показать больше [+] Меньше [-]Prolonged maintenance of water balance by adult females of the American spider beetle, Mezium affine Boieldieu, in the absence of food and water resources
2005
Benoit, J.B. | Yoder, J.A. | Rellinger, E.J. | Ark, J.T. | Keeney, G.D.
Moisture requirements were evaluated for female adults of spider beetles Mezium affine Boieldieu and Gibbium aequinoctiale Boieldieu to determine how they are differentially adapted for life in a dry environment. Features showing extreme desiccation resistance of M. affine were an impermeable cuticle wherein activation energies (43 kJ/mol) were suppressed, daily water losses as little as 0.3%/day with an associated group effect, a low 64% water content and an impressive ability to survive nearly 3 months with no food and water. Behaviorally, the extended period of water stress and fasting was marked by long intervals of physical inactivity (quiescence), as though dead. These characteristics emphasizing water retention rather than gain are shared by G. aequinoctiale and reflect a typical xerophilic water balance profile. Water uptake was restricted to imbibing liquid, as evidenced by uptake of dye-stained droplets of free water and a critical equilibrium activity of 1.00a(v), where the inability to absorb water vapor from the air fails to equilibrate declining water levels (gain not equal to loss) except at saturation. Four-fold reduction in survival time within dry air and accelerated water loss rates with high activation energies for female adults of the closely related winged Prostephanus truncatus (Say) suggest that the enhanced water conservation of spider beetles is due, in part, to fusion of their elytra supplemented by entering into quiescence.
Показать больше [+] Меньше [-]The prevalence of bacterial resistance in clinical, food, water and some environmental samples in Southwest Nigeria Полный текст
2005
The resistance pattern and mechanisms of bacterial isolates obtained from clinical origin, soil, industrial effluent, orange juice products and drinking water were studied using commonly used antibiotics. The microbial load of the water samples, industrial effluent and orange juice products were 1.0 × 10¹−2.25 × 10⁶, 2.15 × 10⁵, and 3.5 × 10⁴−2.15 × 10⁵ cfu mL⁻¹, respectively. The faecal coliform test revealed that only two out of twenty orange juice products had MPN of 2 and 20, the MPN of water ranged from 1−≥1800, while the effluent had MPN of ≥1800. The bacterial isolates that were isolated include E. coli, S. aureus, P. vulgaris, S. marcescens, S. pyogenes, B. cereus, B. subtilis, Micrococcus sp., Klebsiella sp., P. aeruginosa, and Enterobacter sp. Also, clinical and soil isolates of P. aeruginosa were used in the study. Among the eight antibiotics tested for resistance on five strains of each bacterium, seven different resistance patterns were observed among the bacterial isolates obtained from water, effluent and orange juice products. Among the clinical and soil isolates of P. aeruginosa, four multiple-drug resistance patterns were obtained. Thirty strains of E. coli and S. aureus were tested for β-lactamase production and fourteen strains, seven each of E. coli and S. aureus that had high Minimum Inhibitory Concentration values (MIC) for both Amoxycillin and Cloxacillin were positive.
Показать больше [+] Меньше [-]Trophic food web and ecosystem attributes of a water reservoir of the Ria Formosa (south Portugal) Полный текст
2005
Gamito, Sofia | Erzini, Karim
Using a top-down modelling approach, a balanced trophic food web model of a water reservoir of the Ria Formosa lagoonal system was constructed. Few adjustments of input data were necessary to run the model since most of the parameters were estimated at the study site and the characteristics of the water reservoir allowed a high degree of control and precision in terms of sampling and data collection. Trophic levels of the 14 compartments included in the model varied between 1.0 for primary producers and detritus to 3.4 for carnivorous fish and the 14 groups were aggregated in a food chain with six trophic levels. The water reservoir has a detritus based food chain, with the majority of the biomass concentrated in the first two levels, the producers level and the herbivore/detritivore level (97.6%). The transfer efficiencies were low, and decreased with increasing level number, varying between 6.0 and 0.2%. The degree of "ecosystem maturity" was difficult to establish, but several parameters indicate that it could be high. The water reservoir studied, which has similar environmental and ecological characteristics as the Ria Formosa lagoon. is near its carrying capacity. (C) 2004, Elsevier B.V. All rights reserved.
Показать больше [+] Меньше [-]Development of low-cost water-proof biodegradable material from food-by-products using injection molding system
2005
Isobe, S.(National Food Research Inst., Tsukuba, Ibaraki (Japan)) | Tomita, T. | Nagai, M.
Recycling of food-by-products is very important subject. Many trials have been done to reuse by-product, however, almost trials have not been to install the commercial process due to their treatment costs and their qualities. To convert biodegradable stuff is one of their trail fields. However, their products have disadvantage of high cost and low properties against water-resistance. To minimize costs and to improve waterproof property, we used zein-containing corn gluten meal and succeeded in making solid materials by injection molding. We turned the materials into pellets with an extruder, and then molded the pellets into seedling culture pots with an injection molder. This study project was carried out jointly with Showa Sangyo Co., The Japan Steel Works and National Food Research Institute. In this project we were able to successfully reduce costs and to obtain solid molded products for practical use by adopting the injection molding method, which has many advantages in productivity (low costs, high moldability, flexibility to make various shapes of molds). At present, we are working to assess the biodegradable molded material actually applied and to improve materials for different purposes.
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