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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.
Show more [+] Less [-]Food shortage affects flight migration of the giant water bug Lethocerus deyrolli in the prewintering season Full text
2005
Ōba, Shin'ya | Takagi, Hideharu
The endangered giant water bug Lethocerus deyrolli (Vuillefroy) is frequently attracted in large numbers to artificial lights in Japan. To examine factors enhancing flight migration for L. deyrolli, we carried out field work in western Hyogo Prefecture, central Japan, in September during the nonreproductive and prewintering season. The body weight of specimens collected under flight migration (flight bugs) was significantly less than that of those collected in ponds (pond bugs). A field experiment using open cages in a rice paddy field was carried out with two treatments, with and without a food supply. The remaining rate of L. deyrolli for the food present treatment was significantly higher than that for the food absent treatment for the first two days. These results suggest that L. deyrolli would fly in search of food when the food supply of the present habitat becomes unsuitable.
Show more [+] Less [-]The prevalence of bacterial resistance in clinical, food, water and some environmental samples in Southwest Nigeria Full text
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.
Show more [+] Less [-]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.
Show more [+] Less [-]Trophic food web and ecosystem attributes of a water reservoir of the Ria Formosa (south Portugal) Full text
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.
Show more [+] Less [-]Impact of irrigation water scarcity on the socio-economics of agricultural sector and food security in Jordan
2005
Hamdan, M.R.,University of Jordan, Amman (Jordan). Fac. of Agriculture)Salman, A. Z.
The main aim of this paper is to address the impact of irrigation water scarcity on the socio-economics of agricultural sector and the Jordanian food security. The rapid increase in Jordan population have placed unprecedented demand on water sources. The main findings of this paper were that decreasing water supply by 20 percent will be followed by a reduction in the total cultivated area by about 14 percent . This will lead to a decrease in the total net income generated by 15 percent . As a policy implication of this paper, it is suggested that irrigated land base must be maintained in good order to sustain relatively low food prices. New strategies for water development and management are urgently needed and to continue searching means and methods to increase water supply by increasing the investment in the irrigation sector, which can increase water supply and irrigation use efficiency.
Show more [+] Less [-]Fat mimetic capacity of Chlorella vulgaris biomass in oil-in-water food emulsions stabilized by pea protein
2005
Raymundo, A. | Gouveia, L. | Batista, A.P. | Empis, J. | Sousa, I.
Vegetable proteins proved to be good emulsifiers for food emulsions with dietetic advantages. The use of these emulsions as carriers for healthy ingredients, such as colourings, with antioxidant and other beneficial properties, is an interesting subject. In this work, the capacity of the biomass of the microalga Chlorella vulgaris (which has been widely used as a food supplement) as a fat mimetic, and its emulsifier ability, was evaluated. Pea protein emulsions with C. vulgaris addition (both green and orange - carotenogenic) were prepared at different protein and oil contents. The rheological properties of the respective food emulsions were measured in terms of the viscoelastic properties and steady state flow behaviour and texture properties. It was observed that the two microalgal forms evidenced a fat mimetic capacity in these emulsions, the performance of the green stage of this C. vulgaris organism was significantly (p < 0.05) better than the orange stage.
Show more [+] Less [-]Fat mimetic capacity of Chlorella vulgaris biomass in oil-in-water food emulsions stabilized by pea protein Full text
2005
Sousa, Isabel | Raymundo, Anabela | Gouveia, L. | Batista, A.P. | Empis, José
Vegetable proteins proved to be good emulsifiers for food emulsions with dietetic advantages. The use of these emulsions as car- riers for healthy ingredients, such as colourings, with antioxidant and other beneficial properties, is an interesting subject. In this work, the capacity of the biomass of the microalga Chlorella vulgaris (which has been widely used as a food supplement) as a fat mimetic, and its emulsifier ability, was evaluated. Pea protein emulsions with C. vulgaris addition (both green and orange – carotenogenic) were prepared at different protein and oil contents. The rheological properties of the respective food emulsions were measured in terms of the viscoelastic properties and steady state flow behaviour and texture properties. It was observed that the two microalgal forms evidenced a fat mimetic capacity in these emulsions, the performance of the green stage of this C. vulgaris organism was significantly (p < 0.05) better than the orange stage.
Show more [+] Less [-]An easy-to-use semiquantitative food record validated for energy intake by using doubly labelled water technique Full text
2005
Koebnick, Corinna | Wagner, K. | Thielecke, F. | Dieter, G. | Hohne, A. | Franke, A. | Garcia, Ada | Meyer, H. | Hoffmann, I. | Leitzmann, P. | Trippo, U. | Zunft, Hans-Joachim Franz
Background: Estimating dietary intake is important for both epidemiological and clinical studies, but often lacks accuracy. Objective: To investigate the accuracy and validity of energy intake estimated by an easy-to-use semiquantitative food record (EISQFR) compared to total energy expenditure ( TEE) estimated by doubly labelled water technique (EEDLW). Design: TEE was measured in 29 nonobese subjects using the doubly labelled water method over a period of 14 days. Within this period, subjects reported their food consumption by a newly developed semiquantitative food record for 4 consecutive days. Energy intake was calculated using the German Food Code and Nutrition Data Base BLS II.3. Results: A good correlation was observed between EISQFR and EEDLW (r = 0.685, P<0.001). The mean difference between EISQFR and EEDLW was - 1.7 +/- 2.6 MJ/ day ( - 14 +/- 21%, P = 0.002). An underestimation of EISQFR <10% was observed in nine subjects (31%), of 10 - 20% in six subjects (21%), and of >20% in nine subjects (31%). In five subjects (17%), an overestimation of EISQFR was observed. Conclusions: The easy-to-use semiquantitative food record provided good estimates of EI in free-living and nonobese adults without prior detailed verbal instructions. The presented food record has limitations regarding accuracy at the individual level
Show more [+] Less [-]An easy-to-use semiquantitative food record validated for energy intake by using doubly labelled water technique. Full text
2005
Koebnick, C. | Wagner, K. | Thielecke, F. | Dieter, G. | Hoehne, A. | Franke, A. | García, A. | Meyer, Hanno | Hoffmann, I. | Leitzmann, P. | Trippo, U. | Zunft, H. J. F.