Design for Survival: Sustainability for Planet and Structure

Buildings in Port Aransas encounter drastic environmental challenges: the potential catastrophic storm surge and high winds from a hurricane, and daily conditions hostile to buildings, vehicles, and even most vegetation. Its location a few hundred feet from the Gulf of Mexico and near-tropical latitude expose buildings to continuous high humidity, winds laden with scouring sand and corrosive salt, and extremes of temperature and ultraviolet light. Building construction methods are able to address each of these, but doing so in a sustainable way creates significant challenges. The new research building at the Marine Science Institute has been designed and is being constructed to meet the demand for both survivability and sustainability. It is tracking towards formal certification as a LEED Gold structure while being robust and resistant to the harsh coastal environment. The effects of a hurricane are mitigated by elevating buildings and providing a windproof envelope. Ground-level enclosures are designed to be sacrificial and non-structural so they can wash or blow away without imposing damage on the upper portions of the building, and only non-critical functions and equipment will be supported within them. Design features that integrate survivability with sustainability include: orientation of building axis; integral shading from direct summer sunlight; light wells; photovoltaic arrays; collection of rainwater and air conditioning condensate for use in landscape irrigation; reduced impervious cover; xeriscaping and indigenous plants; recycling of waste heat from air conditioning systems; roofing system that reflects light and heat; long life, low maintenance stainless steel, high-tensile vinyl, hard-anodized aluminum and hot-dipped galvanized mountings throughout; chloride-resistant concrete; reduced visual impact; recycling of construction materials.

Decomposition in lake sediments: bacterial action and interaction

This review discusses the processes involved in the decomposition of organic carbon derived initially from structural components of algae and other primary producers. It describes how groups of bacteria interact in time and space in a eutrophic lake. The relative importance of anaerobic and aerobic processes are discussed. The bulk of decomposition occurs within the sediment. The role of bacteria in the nitrogen cycle and the iron cycle, and in sulphate reduction and methanogenesis as the terminal metabolism of organic carbon are described.

Structural and functional properties of the hemoglobin components from the Caspian Sea Acipenser persicus and Acipenser stellatus

Hemoglobin (Hb) variability is a commonly used index of phylogenetic differentiation and molecular adaptation in fish. In the current study, the structural and functional characteristics of Hbs from two Sturgeon species of the Southern Caspian Sea Basin were investigated. After extraction and separation of hemoglobin from whole blood , the polyacrylamide gel electrophoresis (SDSPAGE), native-PAGE and isoelectric focusing (IEF) were used to confirm Hb variability in these fishes. Ion-exchange on CM-cellulose chromatography was used for purification of the dominant Hbs from these fishes. The accuracy of the methods was confirmed by IEF and SDS-PAGE. Spectral studies using fluorescence spectrophotometery, circular dichroism spectropolarimetry (CD) analysis and UV–vis spectrophotometery. Oxygen affinities of these Hbs were compared using Hb-oxygen dissociation curves. Also, the dominant Hbs from these blood fishes were utilized for further experiments. The behavior of Hbs during the denaturation process by n-dodecyl trimethylammonium bromide (DTAB) is investigated by UV–vis spectrophotometer and circular dichroism spectropolarimetry. The thermal denaturation properties of the Hbs wereinvestigated by differential scanning calorimetry (DSC) and Hbs aggregation performed chemically in the presence of dithiotreitol (DTT) by UV–vis spectrophotometer and chemometric study. The results demonstrate a significant relationship between stability of fish hemoglobins and the ability of fish for entering to deeper depths. The UV–Vis absorption spectra identified species of hemoglobin and showed the concentration of oxyHb and metHb decreases and deoxyHb increases upon interaction with DTAB. Besides the UV–vis spectrophotometry, the interaction of DTAB with hemoglobins has been studied using circular dichroism spectropolarimetry analysis. This experiment was utilized to measure the unfolding mechanism and compared alpha-helix secondary structure under different conditions for Hbs. The results reveal that the Acipenser stellatus Hb in comparison with Acipenser persicus Hb has more stability and more structural compactness. Besides, the results confirm the hypothesis that there is a meaningful relation between average habitat depth, partial oxygen pressure, oxygen affinity, structural compactness of Hb, and its stability.