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Total Water (total + water)
Selected AbstractsRegional water resource implications of bioethanol production in the Southeastern United StatesGLOBAL CHANGE BIOLOGY, Issue 9 2009JASON M. EVANS Abstract The Energy Independence and Security Act (EISA) of 2007 mandates US production of 136 billion L of biofuel by 2022. This target implies an appropriation of regional primary production for dedicated feedstocks at scales that may dramatically affect water supply, exacerbate existing water quality challenges, and force undesirable environmental resource trade offs. Using a comparative life cycle approach, we assess energy balances and water resource implications for four dedicated ethanol feedstocks , corn, sugarcane, sweet sorghum, and southern pine , in two southeastern states, Florida and Georgia, which are a presumed epicenter for future biofuel production. Net energy benefit ratios for ethanol and coproducts range were 1.26 for corn, 1.94 for sweet sorghum, 2.51 for sugarcane, and 2.97 for southern pine. Corn also has high nitrogen (N) and water demand (11.2 kg GJnet,1 and 188 m3 GJnet,1, respectively) compared with other feedstocks, making it a poor choice for regional ethanol production. Southern pine, in contrast, has relatively low N demand (0.4 kg GJnet,1) and negligible irrigation needs. However, it has comparatively low gross productivity, which results in large land area per unit ethanol production (208 m2 GJnet,1), and, by association, substantial indirect and incremental water use (51 m3 GJnet,1). Ultimately, all four feedstocks require substantial land (10.1, 3.1, 2.5, and 6.1 million ha for corn, sugarcane, sweet sorghum, and pine, respectively), annual N fertilization (3230, 574, 396, 109 million kg N) and annual total water (54 400, 20 840, 8840, and 14 970 million m3) resources when scaled up to meet EISA renewable fuel standards production goals. This production would, in turn, offset only 17.5% of regional gasoline consumption on a gross basis, and substantially less when evaluated on a net basis. Utilization of existing waste biomass sources may ameliorate these effects, but does not obviate the need for dedicated primary feedstock production. Careful scrutiny of environmental trade-offs is necessary before embracing aggressive ethanol production mandates. [source] Body protein does not vary despite seasonal changes in fat in the White Stork Ciconia ciconiaIBIS, Issue 1 2002Delphine Michard-Picamelot To understand how a large soaring bird, the White Stork Ciconia ciconia, copes with energy constraints, we compared changes in body mass in 14 captive adult storks with the body composition of 12 free-ranging adult storks found dead from accidents. The captive storks, already in an enclosure for several years, were fed ad libitum. They were weighed daily for 1.5,3.5 years using an automatic device. The bodies of the accidentally killed storks were analysed to determine total water, lipid, protein and ash contents, and to assess the biochemical composition of certain organs. Females were on average 20% lighter and 24% smaller than males, but the body mass of the sexes varied in parallel throughout the year. Body mass peaked in December and January (25,30% above minimal body mass), due essentially to large fat stores in subcutaneous and abdominal adipose tissues. Body mass and body lipid rapidly decreased from February to June, whether the storks reared chicks successfully or not, and remained minimal for a few days into July. In contrast to birds using flapping flight, no variation in body protein or pectoral muscle protein was observed while breeding, even though the moult occurred then, nor in August, before the time when wild storks migrate. An endogenous regulation of body fuels is discussed. [source] Peau sèche-rêche et "Hydratation".INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 4 2004Concept de la capture de l'eau organisée comme de la glace Synopsis About sixty years ago Frank and Evans showed, by entropy measurements, that when a "non-polar molecule dissolves in water it modifies the water structure in the direction of greater ,cristallinity', the water builds a microscopic iceberg around it" Now, we propose the "concept of ice-like-water capture": a lowering of organized ice-like water promotes aggregation (loss of solubility) of the filaggrin/keratin1/keratin10 associations through their hydrophobic patches. The capture of ice-like water may be performed by the glucoceramides-rich bilayers in stratum granulosum. Probably, the same process aggregates the proteins of corneocytes envelope as well as corneodesmosomes proteins. According to the "concept of ice-like-water capture", to regulate the keratinization, it is not total water that must be added to the stratum corneum, but ice-like water that must be removed from stratum granulosum. Both petrolatum (lipophilic ingredient) and glycerol (hydrophilic ingredient) would capture the ice-like water, most probably after combination with the lipid bilayers of stratum corneum. Moisturizing cream, when organized in secondary droplets is likely to perform the same action. Measurements by near-infrared reflectance spectroscopy of the skin show that petrolatum; glycerol and/or moisturizing cream enhance the quantity of bulk water (1890,1897 nm band). As the ice-like water is the complement of bulk water, the enhanced bulk water let presume an ice-like water lessening. Some desynchronization (late or forward) of the keratinization/differentiation which confer the somatosensory problems associated with "dry and flaky skin" may be linked to an excess or lack of ice-like. For instance, the winter xerosis, very common by chilling weather, could be explained by an increase of ice-like water driven by the fall of the temperature. Résumé En s'appuyant: 1°-sur d'anciens travaux de thermodynamique montrant, d'une part que les molécules d'eau autour des zones apolaires en solution dans l'eau s'organise selon une structure d'eau-comme-de-la-glace, d'autre part qu'en l'absence de cette eau-comme-de-la-glace les molécules de protéines s'agrègent par leurs zones hydrophobes; 2°-sur des travaux récents utilisant la spectroscopie de l'infrarouge proche; technique qui permet de mesurer la quantité d'eau-en-vrac, forme que prend l'eau-comme-de-la-glace après sa fusion lors de l"établissement de liaisons/interactions hydrophobes; nous proposons le "concept de la capture de l"eau-comme-de-la-glace" selon lequel : 1° la différenciation des kératinocytes, qui se traduit à la fois par l'agrégation des trios filaggrine/K1/K10 (ainsi que notamment la formation de l'enveloppe des cornéocytes et des cornéodesmosomes) est promue par une baisse de la teneur en eau organisée dans le stratum granulosum. La captation de l'eau-comme-de-la-glace pourrait être assurée in situ par la structure lipidique riche en glucocéramides dont l'apparition dans le stratum granulosum est contemporaine du début de la baisse de la teneur en eau; 2° contrairement à la "tradition", la peau sèche-rêche n'est pas améliorée par une augmentation de l'hydratation du stratum corneum mais par la capture d'eau-comme-de-la-glace dans le stratum granulosum. 3° le glycérol, la Vaseline et les crèmes "hydratantes" peuvent concourir à cette capture d'eau-comme-de-la-glace, vraisemblablement après s"être combinés aux bicouches céramidiques du stratum corneum, et ainsi agir depuis ce stratum sur le stratum granulosum. 4°-la baisse hivernale de la température provoque une baisse de la quantité d'eau organisée et confère une aggravation de la peau sèche-rêche. 5°-une désynchronisation de la synthèse ou une modification de la structure et/ou de la composition des bicouches glucocéramidiques du stratum granulosum pourraient être à l'origine de certains types de peau sèche-rêche. [source] RING CHARACTERIZATION OF QUALITY INDICES IN BUTTERHEAD LETTUCE CULTIVATED UNDER MULCH AND BARE SOILJOURNAL OF FOOD QUALITY, Issue 4 2010MARÍA G. GOÑI ABSTRACT Butterhead lettuce was characterized by physical, microbiological and nutritional quality indices as a function of plant zoning and soil management (bare soil and mulch). Quality indices were measured in all the rings from the external toward the internal ratio. Assayed indices were: relative water content, water content, free and bound water, and the ratio between free water and total water, leaf area and color, total microbial counts (TMC) and ascorbic acid content (AA). The lettuce characterization by rings showed a remarkable plant zoning as a function of leaf age and development; also, some initial indices were affected by the soil management employed. Plastic mulches affect the microclimate around the plant, resulting in better plant water status. However, the use of black plastic covers could absorb sunlight therefore increasing soil temperature and causing lower AA and higher TMC in lettuce tissue. PRACTICAL APPLICATIONS During lettuce development, each leaf had a different level of exposure to environmental conditions, such as light, humidity, nutrients absorption and temperature affecting the quality indices of the raw material and introducing a source of variability in the physico-chemical, biochemical, nutritional and microbiological indices within the plant. In this way, the location of the leaf within the whole plant is an important factor to be considered. Moreover, during lettuce heads trading, it is a common practice to remove the external leaves as storage advances. These leaves are more perishable than middle and internal ones because of their direct exposure to environmental conditions. Understanding the way in which physical, microbiological and nutritional indices were distributed in the whole lettuce plant could be of interest, to know the value of the losses of regular green grocers' practices, from a nutritional and a safety point of view. [source] | ||||||||||