The role of water in determining structure and function of macromolecules and macromolecular assemblies /

The interaction of biological molecules with water is an important determinant of structural properties both in molecular assemblies, and in conformation of individual macromolecules. By observing the effects of manipulating the activity of water (which can be accomplished by limiting its concentration or by adding additional solutes, "osmotic stress"), one can learn something about intrinsic physical properties of biological molecules as well as measure an energetic contribution of closely associated water molecules to overall equilibria in biological reactions. Here two such studies are reported. The first of these examines several species of lysolipid which, while present in relatively low concentrations in biomembranes, have been shown to affect many cellular processes involving membrane-protein or membrane-membrane interactions. Monolayer elastic constants were determined by combining X-ray diffraction and the osmotic stress technique. Spontaneous radii of curvature of lysophosphatidylcholines were determined to be positive and in the range +30A to +70A, while lysophosphatidylethanolamines proved to be essentially flat. Neither lysolipid significantly affected the bending modulus of the monolayer in which it was incorporated. The second study examines the role of water in theprocess of polymerization of actin into filaments. Water activity was manipulated by adding osmolytes and the effect on the equilibrium dissociation constant (measured as the criticalmonomer concentration) was determined. As water activity was decreased, the critical concentration was reduced for Ca-actin but not for Mg-actin, suggesting that 10-12 fewer water molecules are associated with Ca-actin in the polymerized state. Thisunexpectedly small amount of water is discussed in the context of the common structural motif of a nucleotide binding cleft.

Second Welland Canal - Book 3, Survey Map 3 - Vanalstines Creek and Back Water in Thorold

Survey map of the Second Welland Canal created by the Welland Canal Company showing the canal in Thorold Township near Port Robinson. Identified structures associated with the Canal include towing path. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks are also identified and include roads (ex. Road to Font Hill), bridges, Back Water, and Vanalstines Creek. Properties and property owners of note are: Lots 203, 204, and 205, John Coulter, and Samuel Hill.

Second Welland Canal - Book 3, Survey Map 4 - Back Water in Thorold

Survey map of the Second Welland Canal created by the Welland Canal Company showing the Back Water from the canal in Thorold Township near Port Robinson. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks are also identified and include the Back Water from the canal. Properties and property owners of note are: Lots 205 and 206, and McAlpine.

Development of Bioreactors for Nitrifying Water In Closed System Hatcheries Of Penaeid And Non-Penaeid Prawns

In the present study the development of bioreactors for nitrifying water in closed system hatcheries of penaeid and non-penaeid prawns. This work is an attempt in this direction to cater to the needs of aquaculture industry for treatment and remediation of ammonia and nitrate in penaeid and non-penaeid hatcheries, by developing nitrifying bacteria allochthonous to the particular environment under consideration, and immobilizing them on an appropriately designed support materials configured as reactors. Ammonia toxicity is the major limiting factors in penaeid and non-penaeid hatchery systems causing lethal and sublethal effects on larvae depending on the pH values. Pressing need of the aquaculture industry to have a user friendly and economically viable technology for the removal of ammonia, which can be easily integrated to the existing hatchery designs without any major changes or modifications. Only option available now is to have biological filters through which water can be circulated for the oxidation of ammonia to nitrate through nitrite by a group of chemolithotrophs known as nitrifying bacteria. Two types of bioreactors have been designed and developed. The first category named as in situ stringed bed suspended bioreactor(SBSBR) was designed for use in the larval rearing tanks to remove ammonia and nitrite during larval rearing on a continuous basis, and the other to be used for nitrifying freshly collected seawater and spent water named as ex situ packed bed bioreactior(PBBR). On employing the two reactors together , both penaeid and non-penaeid larval rearing systems can be made a closed recirculating system at least for a season. A survey of literature revealed that the in situ stringed bed suspended reactor developed here is unique in its design, fabrication and mode of application.

The Right to Water in the Case-Law of the Inter-American Court of Human Rights

The human right to water is nowadays more broadly recognised, mainly due to the essential societal function that this resource plays; likewise, because of the present water scarcity is generating conflicts between its different uses. Thus, this right aims at protecting human beings by guaranteeing access to clean water that is essential to satisfy vital human needs. Similarly, access to clean water is an important element to guarantee other rights including the right to life and health. The recognition of the right to water is mainly achieved in two ways: as a new and independent right and as a subordinate or derivative right. Concerning the latter, the right to water can emanate from civil and political rights, such as the right to life; or can be derived from economic, social and cultural rights, including the right to health, the right to an adequate standard of living, and the right to housing. This contribution explores the position of the Inter-American Court of Human Rights regarding the right to water, and analyses whether the Court has recognised the right to water and, if so, in which manner.

Sustainable Development and the Right to Water in Colombia

Water, considered as an environmental resource and as an economic and social good, should be part of the Colombian public agenda, not only not only in terms of the use and preservation of hydro resources, but also in terms of the social implications of its possession and use. The world wide preoccupation with the diminution of natural resources, species extinction and water shortage has its origins in the seventies. One of the results was the establishment of international conventions and agreements to achieve responsible management of natural resources. Regarding water as a resource, it is intrinsically bound to the Earth’s natural processes and ecosystems. As regards the Colombian case, the “right to water in Colombia” is analyzed taking into account: water as an integral part of sustainable development, the right to water as a global debate and, finally, the right to water in the Colombian context within the explanatory framework of the Water Referendum.

Water in our lives. 'El agua en nuestras vidas'.

Proyecto educativo indicado para el nivel de Educación Infantil que está basado en una metodología flexible e integradora de nuevas experiencias. El cuaderno plantea una serie de actividades pedagógicas que se recogen en trece fichas, desde dos perspectivas: una primera parte se centra en el estudio del agua a través de diferentes actividades que enfocan el tema desde diferentes áreas de conocimiento; la segunda parte, plantea actividades de intercambio que se pueden realizar con otras escuelas tanto a escala interregional como de Europa. El objetivo de las actividades es aprender a compartir e intercambiar experiencias pedagógicas con otros centros escolares. Las actividades han de estar integradas dentro del Proyecto Curricular de Centro.

Estimated Mortality of Selected Migratory Bird Species from Mowing and Other Mechanical Operations in Canadian Agriculture

Mechanical operations such as mowing, tilling, seeding, and harvesting are well-known sources of direct avian mortality in agricultural fields. However, there are currently no mortality rate estimates available for any species group or larger jurisdiction. Even reviews of sources of mortality in birds have failed to address mechanical disturbance in farm fields. To overcome this information gap we provide estimates of total mortality rates by mechanical operations for five selected species across Canada. In our step-by-step modeling approach we (i) quantified the amount of various types of agricultural land in each Bird Conservation Region (BCR) in Canada, (ii) estimated population densities by region and agricultural habitat type for each selected species, (iii) estimated the average timing of mechanical agricultural activities, egg laying, and fledging, (iv) and used these values and additional demographical parameters to derive estimates of total mortality by species within each BCR. Based on our calculations the total annual estimated incidental take of young ranged from ~138,000 for Horned Lark (Eremophila alpestris) to as much as ~941,000 for Savannah Sparrow (Passerculus sandwichensis). Net losses to the fall flight of birds, i.e., those birds that would have fledged successfully in the absence of mechanical disturbance, were, for example ~321,000 for Bobolink (Dolichonyx oryzivorus) and ~483,000 for Savannah Sparrow. Although our estimates are subject to an unknown degree of uncertainty, this assessment is a very important first step because it provides a broad estimate of incidental take for a set of species that may be particularly vulnerable to mechanical operations and a starting point for future refinements of model parameters if and when they become available.

Dual technological development in Botswana agriculture: A Stochastic input distance function approach

To improve the welfare of the rural poor and keep them in the countryside, the government of Botswana has been spending 40% of the value of agricultural GDP on agricultural support services. But can investment make smallholder agriculture prosperous in such adverse conditions? This paper derives an answer by applying a two-output six-input stochastic translog distance function, with inefficiency effects and biased technical change to panel data for the 18 districts and the commercial agricultural sector, from 1979 to 1996 This model demonstrates that herds are the most important input, followed by draft power. land and seeds. Multilateral indices for technical change, technical efficiency and total factor productivity (TFP) show that the technology level of the commercial agricultural sector is more than six times that of traditional agriculture and that the gap has been increasing, due to technological regression in traditional agriculture and modest progress in commercial agriculture. Since the levels of efficiency are similar, the same patient is repeated by the TFP indices. This result highlights the policy dilemma of the trade-off between efficiency and equity objectives.