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Among the systems that aim to help users to perform map reading tasks, augmented reality (AR) is one of the most promising. However, the impact of this new technology in terms of acceptance, motiva...

In this work an evaluation procedure of the use of colour hue and texture for 3D symbolization of indoor environments using RGB-D data is presented. The main characteristics of the proposed method involve RGB-D cameras to collect colour and depth data and the evaluation of the visual variables colour hue and texture combined with visual aspects such as lighting and camera configuration for the symbolization of 3D indoor environments. High quality coloured point clouds of indoor environments are obtained with the Kinect sensor and then registered and processed in order to create 3D models. These sets of point clouds can be detected, recognized and classified under one of the three following main categories: ceiling, wall or floor. After classification is done, the resulting point clouds are properly treated as 3D triangular meshes in the MeshLab software. These meshes are then filtered to form complete surfaces which are then refined before being considered for visual variable application. We evaluated the...

All life processes are subject to time constraints. At the cellular level, damage repair and cell cycle arrest are interrelated, allowing sufficient time for repair prior to cell cycle progression. Organisms have evolved so that developmental timing is linked to environmental conditions, such as nutrient availability and predation. Recent results in mammals regarding species-specific differences in cell cycle arrest and DNA damage suggest that a stable cell cycle arrest is a feature of longer-lived species. The implication of these results is that longer-lived species delay cell cycle progression to a greater degree than shorter-lived species, allowing for higher fidelity repair. We suggest that the ability to devote longer periods of time to repair and maintenance is a key feature of longer-lived species, and that evolutionary pressure to complete repair and resume cell division is a determinant of species lifespan. Thus, time is a resource that must be managed by the organism to attempt to maximize the fidelity of repair, while completing development and reproduction in the limited window of opportunity afforded by environmental pressures. This viewpoint on time as a resource has implications for theories regarding the aging process and the development of species lifespan.

A heuristic ontology is an ontology that describes concepts using heuristics (‘rules of thumb’ or guidelines) rather than axioms as in a classical ontology. The heuristics can be used to establish whether a given instance is a member of the concept defined by the heuristics in a data-driven manner. The approach may be particularly useful if data is poor, irregular or incomplete. A heuristic ontology was used to determine whether given collections of land parcels are valid spatio-temporal sequences and thus automatically derive sequence data that would otherwise have to be maintained manually, achieving levels of precision of 94% and recall of 67%.

The application of nonimmersive virtual reality (VR) to the creation of rich cartographic representations in 3D is a current research area in cartography. However, the cartographic knowledge needed...

The main aim of this paper is to measure the acceptability and effectiveness of three spatial analysis tools applied to functional map interfaces, by means of answering if the common web map user can make use of these tools and if this use is beneficial to a spatial task accomplishment. Also it was verified what user’s attributes influence the performance. To achieve this, a quantitative statistical analysis with a random user sample was held, with tests carried out remotely. Results showed that previous map experience and higher educational levels may influence positively the manipulation of the interface and that there is not a clear indication that the presence of the spatial analysis tools analysed had a positive influence on the tasks’ results. For the other side, users that choose to use these tools had significantly better performance than those who did not use them.

Having looked the beast of the past in the eye, having asked and received forgiveness and having made amends, let us shut the door to the past—not in order to forget it but in order not to allow it...

We investigated the effect of protein- and non protein-thiol oxidation on DNA double-strand-break (DSB) rejoining after irradiation and its relevance in the survival of CHO cells.We used mutant cells null for glucose 6 phosphate dehydrogenase (G6PD) activity since reducing equivalents, required for reduction of oxidized thiols, are typically generated through G6PD regulated production of NADPH. Cellular thiols were oxidized by pre-incubating the cells with hydroxyethyldisulphide (HEDS), the oxidized form of mercaptoethanol (ME). The concentrations of the intracellular and extracellular non-protein thiols (NPSH), glutathione, cysteine and mercaptoethanol were quantitated by HPLC. Protein thiols (PSH) were estimated using Ellman's reagent. Cell survival was determined by clonogenic assay. The induction and rejoining of DSB in cells was quantitated by Pulse Field Gel Electrophoresis after exposure to ionizing radiation.Much lower bioreduction of HEDS was found in the G6PD deficient mutants (E89) than in the wild-type cells (K1). A 1 h treatment of E89 cells with HEDS produced almost complete depletion of non-protein thiol (NPSH) and a 26% decrease in protein thiols. Only minor changes were found under similar conditions with K1 cells. When exposed to gamma radiation in the presence of HEDS, the G6PD null mutants exhibited a higher cell killing and decreased rate and extent of rejoining of DSB than were observed in K1 cells. Moreover, when the G6PD deficient cells were transfected with the gene encoding wild-type G6PD (A1A), they recovered close to wild-type cellular thiol status, cell survival and DSB rejoining.These results suggest that a functioning oxidative pentose phosphate pathway is required for DSB rejoining in cells exposed to a mild thiol oxidant.

On December 8, 1995, a street vendor, Roland Smith, Jr., entered Freddy's, the discount clothing store on 125th Street in Harlem that he, along with scores of others, had been picketing for several weeks. He fired a gun indiscriminately, killing several people. He doused the store with a flammable liquid, and before turning his weapon on himself, ignited it. In all, eight people died, including the deranged Smith. Others were injured and the store was ruined. What's the genesis of this tragedy? It arose from a contentious commercial dispute between a Jewish landlord and his African‐American tenant. It happened when the tenant's lease renewal was denied, and he sought, through economic and social pressure, to reverse that decision. But the roots of the clash lie deeper, embedded in historic resentments, racial and class antagonisms, the disappearance of jobs, and the political gamesmanship endemic to the community. To avoid repeating its mistakes, we study history. Even now, so recently removed, the Harlem...

Trichloromethyl and trichloromethyl peroxyl radicals are known to be produced during CCl4 biotransformation and are considered to be critical for deleterious effects of this haloalkane. In this work we describe our studies on the interaction of both free radicals with a lipid-soluble derivative of the amino acid proline in a model system. The analysis of the reaction products formed by gas chromatography-mass spectrometry of the sylilated derivatives revealed the formation of at least 11 reaction products under anaerobic conditions and 13 under aerobic atmosphere. All of them were tentatively identified and all but 2 were proline analogs. Only 3 incorporated in their structure CCl3 or CCl2 portions of the CCl4 molecule and, consequently, most of the adducts formed would be missed during regular procedures most toxicologists use to determine CCl4. Results were analyzed in relation to the known role of proline in collagen metabolism and of this protein in liver cirrhosis.

A pulsed field gel electrophoresis technique, asymmetric field inversion gel electrophoresis (AFIGE), was used to evaluate induction by X-rays of DNA damage in CHO cells. The fraction of DNA activity released from the plug (FAR) was used as a measure for the amount of radiation-induced DNA damage, predominantly DNA double-strand breaks (dsb) (Stamato and Denko 1990), and was determined at various stages of growth and phases of the cell cycle in a range of doses between zero and 70 Gy. The FAR per unit dose fluctuated throughout the cell cycle and was high for cells irradiated in G1; it decreased as cells entered S and reached a minimum in the middle of this phase. The FAR per unit dose increased again as cells progressed towards the end of S, and reached values in G2 similar to those measured in G1. When damage was introduced into DNA by means of 125I decay similar fluctuations in the FAR per decay were observed throughout the cell cycle, suggesting that the variations in the FAR per unit of radiation dose observed throughout the cell cycle do not derive from alterations in the induction of dsb. The fluctuations in the FAR per unit dose throughout the cell cycle were quantitatively similar to the fluctuations in the fraction of activity eluted in irradiated cells assayed by the non-unwinding filter elution assay throughout the cycle (Okayasu et al. 1988), and suggest that both techniques respond to similar DNA replication-associated alterations of the biophysical and/or biochemical properties of the DNA molecule. It is concluded that caution needs to be exercised before differences observed in the FAR between different cell lines or between various phases of the cell cycle after exposure to a given dose of radiation are interpreted as suggesting differences in the induction of DNA dsb.