Human sensitivity to phase perturbations in natural images:A statistical framework

Fourier-phase information is important in determining the appearance of natural scenes, but the structure of natural-image phase spectra is highly complex and difficult to relate directly to human perceptual processes. This problem is addressed by extending previous investigations of human visual sensitivity to the randomisation and quantisation of Fourier phase in natural images. The salience of the image changes induced by these physical processes is shown to depend critically on the nature of the original phase spectrum of each image, and the processes of randomisation and quantisation are shown to be perceptually equivalent provided that they shift image phase components by the same average amount. These results are explained by assuming that the visual system is sensitive to those phase-domain image changes which also alter certain global higher-order image statistics. This assumption may be used to place constraints on the likely nature of cortical processing: mechanisms which correlate the outputs of a bank of relative-phase-sensitive units are found to be consistent with the patterns of sensitivity reported here.

A study of thermodynamic characteristics and predictive computer modelling of an air to water heat pump system

A study on heat pump thermodynamic characteristics has been made in the laboratory on a specially designed and instrumented air to water heat pump system. The design, using refrigerant R12, was based on the requirement to produce domestic hot water at a temperature of about 50 °C and was assembled in the laboratory. All the experimental data were fed to a microcomputer and stored on disk automatically from appropriate transducers via amplifier and 16 channel analogue to digital converters. The measurements taken were R12 pressures and temperatures, water and R12 mass flow rates, air speed, fan and compressor input powers, water and air inlet and outlet temperatures, wet and dry bulb temperatures. The time interval between the observations could be varied. The results showed, as expected, that the COP was higher at higher air inlet temperatures and at lower hot water output temperatures. The optimum air speed was found to be at a speed when the fan input power was about 4% of the condenser heat output. It was also found that the hot water can be produced at a temperature higher than the appropriate R12 condensing temperature corresponding to condensing pressure. This was achieved by condenser design to take advantage of discharge superheat and by further heating the water using heat recovery from the compressor. Of the input power to the compressor, typically about 85% was transferred to the refrigerant, 50 % by the compression work and 35% due to the heating of the refrigerant by the cylinder wall, and the remaining 15% (of the input power) was rejected to the cooling medium. The evaporator effectiveness was found to be about 75% and sensitive to the air speed. Using the data collected, a steady state computer model was developed. For given input conditions s air inlet temperature, air speed, the degree of suction superheat , water inlet and outlet temperatures; the model is capable of predicting the refrigerant cycle, compressor efficiency, evaporator effectiveness, condenser water flow rate and system Cop.

The application of remote sensing to water resources

Techniques are developed for the visual interpretation of drainage features from satellite imagery. The process of interpretation is formalised by the introduction of objective criteria. Problems of assessing the accuracy of maps are recognized, and a method is developed for quantifying the correctness of an interpretation, in which the more important features are given an appropriate weight. A study was made of imagery from a variety of landscapes in Britain and overseas, from which maps of drainage networks were drawn. The accuracy of the mapping was assessed in absolute terms, and also in relation to the geomorphic parameters used in hydrologic models. Results are presented relating the accuracy of interpretation to image quality, subjectivity and the effects of topography. It is concluded that the visual interpretation of satellite imagery gives maps of sufficient accuracy for the preliminary assessment of water resources, and for the estimation of geomorphic parameters. An examination is made of the use of remotely sensed data in hydrologic models. It is proposed that the spectral properties of a scene are holistic, and are therefore more efficient than conventional catchment characteristics. Key hydrologic parameters were identified, and were estimated from streamflow records. The correlation between hydrologic variables and spectral characteristics was examined, and regression models for streamflow were developed, based solely on spectral data. Regression models were also developed using conventional catchment characteristics, whose values were estimated using satellite imagery. It was concluded that models based primarily on variables derived from remotely sensed data give results which are as good as, or better than, models using conventional map data. The holistic properties of remotely sensed data are realised only in undeveloped areas. In developed areas an assessment of current land-use is a more useful indication of hydrologic response.

Strategies for public engagement on environmental matters:you can lead a horse to water, but can you make it drink?

With no tangible evidence of widespread public engagement in the UK on matters relating to the environment, this article assesses the benefits of adopting the principles of key theoretical models on learning (e.g., Kolb's Experiential Model) in environmental campaigns. In addition, in order to facilitate the transition from environmental knowledge/awareness, to the adoption of proenvironmental behavior, the article reviews some of the key internal and external drivers to achieving sustained behavioral change.

Transglutaminase 2 interacts with syndecan-4 and CD44 at the surface of human macrophages to promote removal of apoptotic cells

Tissue transglutaminase (TG2) is a multifunctional protein cross-linking enzyme that has been implicated in apoptotic cell clearance but is also important in many other cell functions including cell adhesion, migration and monocyte to macrophage differentiation. Cell surface-associated TG2 regulates cell adhesion and migration, via its association with receptors such as syndecan-4 and β1 and β3 integrins. Whilst defective apoptotic cell clearance has been described in TG2-deficient mice, the precise role of TG2 in apoptotic cell clearance remains ill-defined. Our work addresses the role of macrophage extracellular TG2 in apoptotic cell corpse clearance. Here we reveal TG2 expression and activity (cytosolic and cell surface) in human macrophages and demonstrate that inhibitors of protein crosslinking activity reduce macrophage clearance of dying cells. We show also that cell-impermeable TG2 inhibitors significantly inhibit the ability of macrophages to migrate and clear apoptotic cells through reduced macrophage recruitment to, and binding of, apoptotic cells. Association studies reveal TG2-syndecan-4 interaction through heparan sulphate side chains, and knockdown of syndecan-4 reduces cell surface TG2 activity and apoptotic cell clearance. Furthermore, inhibition of TG2 activity reduces crosslinking of CD44, reported to augment AC clearance. Thus our data define a role for TG2 activity at the surface of human macrophages in multiple stages of AC clearance and we propose that TG2, in association with heparan sulphates, may exert its effect on AC clearance via a mechanism involving the crosslinking of CD44.

Public libraries and the right to the [smart] city

The future of public libraries has been threatened by funding cuts and new digital technologies which have led many people to question their traditional role and purpose. However, freedom of information, ready access to knowledge and information literacy in all its digital and analog guises are more important than ever. Thus, public libraries remain significant spaces and places where people can socially interact and learn. In many countries public libraries are reinventing themselves and part of this process has been the redesign of library services and the design and construction of new library building and facilities that articulate the values, purpose and role of what has been termed 'the next library'. Following discussion of new library developments in London, Birmingham and Worcester in the UK, Aarhus in Denmark and Helsinki in Finland, the article concludes that public libraries are now both social and media spaces as well as being important physical places that can help city dwellers decide what type of urban world they want to see.

Redefining 'media' using a 'media-as-a-constitutional-component' concept:an evaluation of the need for the European Court of Human Rights to alter its understanding of 'media' within a new media landscape

This paper considers the impact of new media on freedom of expression and media freedom within the context of the European Convention on Human Rights and European Court of Human Rights jurisprudence. Through comparative analysis of US jurisprudence and scholarship, this paper deals with the following three issues. First, it explores the traditional purpose of the media, and how media freedom, as opposed to freedom of expression, has been subject to privileged protection, within an ECHR context at least. Secondly, it considers the emergence of new media, and how it can be differentiated from the traditional media. Finally, it analyses the philosophical justifications for freedom of expression, and how they enable a workable definition of the media based upon the concept of the media-as-a-constitutional-component.

A környezethez való jog és a Kiotói Jegyzőkönyv (Right to environment and Kyoto Protocol)

A Kiotói Jegyzőkönyv az 1992-ben Rio de Janeiro-ban megrendezésre került Környezet és Fejlődés Világkonferenciáján elfogadott nyilatkozatának 1997-ben aláírt kiegészítő jegyzőkönyve. A Kiotói Jegyzőkönyvben minden aláíró ország vállalta, hogy egy bizonyos százalékos arányban csökkenti országában a kibocsátott üvegházhatást okozó gázok mennyiségét, ezáltal mérsékelve a globális felmelegedés előrehaladtát. A Jegyzőkönyvhöz az Egyesült Államok és több fejlő ország, mint Kína vagy India gazdasági megfontolásból másrészt politikai szűklátókörűségből nem csatlakozott. Ez azonban a komoly aggályokat vet fel azzal kapcsolatban, hogy a környezetvédelmi szabályokat betartó államok erőfeszítései önmagában elegendőek lesznek-e a globális felmelegedés megállítására, de legalábbis csökkentésére. _____________ The Kyoto Protocol signed in the Japanese city in Kyoto in 1997 is a supplemental document to the United Nations Conference on Environment and Development organized in Rio de Janeiro. In the Kyoto Protocol individual countries have mandatory emissions targets for the greenhouse gases they must meet to slow down global warming. The United States of America, and several developing countries, as China and India did not yet joined the Protocol partly because of economic reasons and other ways because of narrow-minded political interests. This brings up serious doubt weather the efforts of the parties of the Protocol can make any change in the recent global processes.

Evaluating "xeriscape" the alternative to water conservation in Florida

This thesis develops and tests an evaluative approach to assessing the acceptance of xeriscape as an alternative planting design method among landscape architects in South Florida. South Florida was chosen for its large number of practicing landscape architects and increasing water shortages due to the large infusion of people into the area. ^ A survey was developed and mailed to 95 subjects in South Florida who are landscape architects or related professionals. The responses to the questions were either yes or no, for the most part, and were designed to assess the acceptance, use, knowledge and practice of xeriscape in this region. ^ The results of the survey showed a lack of in-depth knowledge of the seven principles of xeriscape, few true xeriscapes instituted by the water departments are in the region, and that the government sector is the main advocate of the xeriscape concept. ^

Spatial and temporal distributions of epiphytic diatoms growing on Thalassia testudinum Banks ex König: relationships to water quality

The spatial and temporal distributions of the epiphytic diatom flora on Thalassia testudinum was described within the Florida Bay estuary and at one Atlantic site east of the Florida Keys over a 1-year period. Species of the genus Mastogloia dominated the epiphytic diatom flora (82 out of 332 total species). Nonmetric Multidimensional Scaling (NMDS) and Analysis of Similarity (ANOSIM) revealed four distinct spatial assemblages and two temporal assemblages. Eastern and western Florida Bay assemblages were identified within the estuary. The eastern diatom assemblage was characterized by high relative abundances of Brachysira aponina and Nitzschia liebetruthii, while the western assemblage was characterized by the abundance of Reimerothrix floridensis, particularly during summer. Two diverse and distinct marine assemblages, one located in the Gulf of Mexico along the western edge of Florida Bay and the other behind the Florida reef tract in the Atlantic Ocean, were also identified. Analysis of the spatial distribution of diatoms and water quality characteristics within Florida Bay suggest that these assemblages may be structured by salinity and nutrient availability, particularly P. The Gulf of Mexico and the western Florida Bay assemblages were associated with higher water column salinities and TP concentrations and lower DIN concentrations and TN:TP ratios relative to the eastern Florida Bay assemblage. The temporal variation in diatom assemblages was associated with water temperature, though temporal indicator species were few relative to the number of spatial indicators.

Historic primary producer communities linked to water quality and hydrologic changes in the northern Everglades

The northern Everglades Water Conservation Areas have experienced recent ecological shifts in primary producer community structure involving marl periphyton mats and dense Typha-dominated macrophyte stands. Multiple investigations have identified phosphorus (P) as a driver of primary producer community structure, but effects of water impoundment beginning in the 1950s and changes in water hardness [e.g., (CaCO3)] have also been identified as a concern. In an effort to understand pre-1950, primary producer community structure and identify community shifts since 1950, we measured pigment proxies on three sediment cores collected in Water Conservation Area-2A (WCA-2A) along a phosphorus enrichment gradient. Photosynthetic pigments, sediment total phosphorus content (TP), organic matter, total organic carbon and nitrogen were used to infer historic primary producer communities and changes in water quality and hydrology regulating those communities. Excess 210Pb was used to establish historic dates for the sediment cores. Results indicate the northern area of WCA-2A increased marl deposition and increased algal abundance ca. 1920. This increase in (presumably) calcareous periphyton before intensive agriculture and impoundment suggest canal-derived calcium inputs and to some extent early drainage effects played a role in initiating this community shift. The northern area community then shifted to Typha dominance around 1965. The areas to the south in WCA-2A experienced increased marl deposition and algal abundance around or just prior to 1950s impoundment, the precise timing limited by core age resolution. Continued increases in algal abundance were evident after 1950, coinciding with impoundment and deepening of canals draining into WCA-2A, both likely increasing water mineral and nutrient concentrations. The intermediate site developed a Typha-dominated community ca. 1995 while the southern-most core site WCA-2A has yet to develop Typha dominance. Numerous studies link sediment TP >650 mg P/kg to marsh habitat degradation into Typha-dominance. The northern and intermediate cores where Typha is currently support this previous research by showing a distinct shift in the sediment record to Typha dominance corresponding to sediment TP between 600 and 700 mg P/kg. These temporal and spatial differences are consistent with modern evidence showing water-column gradients in mineral inputs (including Ca, carbonates, and phosphorus) altering primary producer community structure in WCA-2A, but also suggest hydroperiod has an effect on the mechanisms regulating periphyton development and Typha dominance.

Trajectories of Vegetation Response to Water Management in Taylor Slough, Everglades National Park, Florida

Ecosystem management practices that modify the major drivers and stressors of an ecosystem often lead to changes in plant community composition. This paper examines how closely the trajectory of vegetation change in seasonally-flooded wetlands tracks management-induced alterations in hydrology and soil characteristics. We used trajectory analysis, a multivariate method designed to test hypotheses about rates and directions of community change, to examine vegetation shifts in response to changes in water management practices within the Taylor Slough basin of Everglades National Park. We summarized vegetation data by non-metric multidimensional scaling ordination, and examined the time trajectory of each site along environmental vectors representing hydrology and soil phosphorus gradients. In the Taylor Slough basin, vegetation change trajectories closely followed the hydrologic changes caused by the operation of water pumps and detention ponds adjacent to the canals. We also observed a shift in vegetation composition along a vector of increasing soil phosphorus, which suggests the need for implementing measures to avoid P-enrichment in southern Everglades marl prairies. This study indicates that shifts in vegetation composition in response to changes in hydrologic conditions and associated parameters may be detected through trajectory analysis, thereby providing feedback for adaptive management of wetland ecosystems.