Prominent Field for Shape Processing and Analysis of?Archaeological Artifacts

Archaeological artifacts are an essential element of archaeological research. They provide evidence of the past and enable archaeologists to obtain qualified conclusion. Nowadays, many artifacts are scanned by 3D scanners. While convenient in many aspects, the 3D representation is often unsuitable for further analysis, due to flaws in the scanning process or defects in the original artifacts. We propose a new approach for automatic processing of scanned artifacts. It is based on the definition of a new direction field on surfaces (a normalized vector field), termed the prominent field. The prominent field is oriented with respect to the prominent feature curves of the surface. We demonstrate the applicability of the prominent field in two applications. The first is surface enhancement of archaeological artifacts, which helps enhance eroded features and remove scanning noise. The second is artificial coloring that can replace manual artifact illustration in archaeological reports.     

Aesthetics and usability of in-vehicle navigation displays

This research evaluates the aesthetics and usability of various in-vehicle electronic navigation map configurations. Study 1 adapted the aesthetics scale (Lavie and Tractinsky, 2004) to accommodate evaluations of map displays. Study 2 examined map displays that vary in the amount of data presented, their abstraction level and color schema, using objective and subjective usability measures. Maps with minimal detail produced best performances and highest evaluations. Abstractions were found to be advantageous when combined with reduced amount of detail and specific color schemas. Moderate abstractions were sufficient for obtaining the desired benefits. The color schema mainly affected the objective measures, pointing to the importance of good contrast between the cursor and the map colors. Study 3 further examined map schemas. Color schemas again had no effect on the perceptions of aesthetics and usability. Overall, similar results and high correlations were found for the perceived aesthetics and usability scales, indicating the connection between perceived aesthetics and usability. Lower correlations were found between the actual usability (performance) and the aesthetics scale. Finally, users’ usability evaluations were not always in line with their actual performance, pointing to the importance of using objective usability measures.     

E-empowerment: Empowerment by the Internet

This article focuses on the concept of empowerment and the ways in which the Internet is being utilized as an empowering tool. This analysis ranges from the personal to the global levels and the consequences of that empowerment are also discussed. We propose a four-level model that serves to explain what we term E-empowerment and the effects that can be observed at each of the four levels, ranging from (1) the personal; (2) the interpersonal; (3) group; and (4) citizenship. The potential for future development of E-empowerment is also discussed.     

Castration prevents calcium channel blocker-induced gingival hyperplasia in beagle dogs

1. The purpose of this study was to investigate testosterone's role on the calcium channel antagonist oxodipine-inducing gingival hyperplasia in a dog model. 2. Two experiments were conducted using castrated and intact male dogs. Oxodipine was administered orally for 90 days, at a dose of 24 mg/kg/day. In the first experiment, the occurrence of gingival hyperplasia was evaluated. In the second, the gingival index (GI) and gingival hyperplasia index (GHI) were recorded and correlated with serum levels of testosterone. 3. A significant positive correlation between GI, GHI and plasma testosterone was noted. Castrated dogs were injected with testosterone, 4 months after the start of oxodipine treatment, while in the non-castrated dogs, administration of oxodipine was stopped. Castration correlated with lack of GH, while testosterone injection to the same dogs was associated with an increase of GI and GHI. 4. Since it is known that testosterone receptors are present in the gingiva, it is proposed that oxodipine-induced gingival hyperplasia could be mediated by the calcium channel blocker on plasma testosterone levels.     

On the a-posteriori error bounds for the solution of ordinary nonlinear differential equations

This paper advances a procedure to compute the a-posteriori error bounds for the solution of a wide class of ordinary differential equations with given initial conditions. The method is based on an iterative scheme which yields upper and lower bounds which approach each other. The convergence of these iterations is proved analytically. Application of the proposed method is demonstrated by several examples. The method is independent of the integration scheme used. Also, separate bounds for each component of the solution are specifically available as a function of time compared to the bound on the norm yielded by conventional methods.     

An ecology of ideology: theory and evidence from four populations

This paper analyzes the founding rates of two types of Jewishagricultural cooperatives, the moshav and the kibbutz, to showhow political ideology intersects with resource requirementsto produce competition and mutualism between organizations.These two populations, which share ideology and a resource base,competed with each other. They both enjoyed mutualism with thepopulation of credit cooperatives, which represented a kindredideology, but relied on different resources. They both sufferedcompetition from the population of corporations, which representeda rival ideology, capitalism.     

Fabrication and characterization of PCL/gelatin/chitosan ternary nanofibrous composite scaffold for tissue engineering applications

In the present study, we have fabricated a ternary composite nanofibrous scaffold from PCL/gelatin/chitosan, by electrospinning technique, using a solvent system—chloroform/methanol for polycaprolactone (PCL) and acetic acid for gelatin and chitosan, for tissue engineering applications. Field emission scanning electron microscopy (FE-SEM) was used to investigate the fiber morphology of the scaffold and it was found that the fiber morphology was influenced by the concentrations of PCL, gelatin, and chitosan in polymer solution during electrospinning. X-ray diffraction, Fourier transform infrared, and thermogravimetric (TG) analysis results showed some interactions among the molecules of PCL, gelatin, and chitosan within the scaffold. In-vitro cell culture studies were done by seeding L929 mouse fibroblasts on fabricated composite scaffold, which confirmed the cell viability, high cell proliferation rate, and cell adhesion on composite scaffold as indicated by MTT assay, DNA quantification, and FE-SEM analysis of cell-scaffold construct. Thus, the ternary composite scaffold made from the combination of PCL (synthetic polymer), gelatin, and chitosan (natural polymer) may find potential application in tissue engineering.     

Age, skill, and hazard perception in driving

This study examined the effects of age and driving experience on the ability to detect hazards while driving; namely, hazard perception. Studies have shown that young-inexperienced drivers are more likely than experienced drivers to suffer from hazard perception deficiencies. However, it remains to be determined if this skill deteriorates with advancing age. Twenty-one young-inexperienced, 19 experienced, and 16 elderly drivers viewed six hazard perception movies while connected to an eye tracking system and were requested to identify hazardous situations. Four movies embedded planned, highly hazardous, situations and the rest were used as control. Generally, experienced and older-experienced drivers were equally proficient at hazard detection and detected potentially hazardous events (e.g., approaching an intersection, pedestrians on curb) continuously whereas young-inexperienced drivers stopped reporting on hazards that followed planned, highly hazardous situations. Moreover, while approaching T intersections older and experienced drivers fixated more towards the merging road on the right while young-inexperienced drivers fixated straight ahead, paying less attention to potential vehicles on the merging road. The study suggests that driving experience improves drivers’ awareness of potential hazards and guides drivers’ eye movements to locations that might embed potential risks. Furthermore, advanced age hardly affects older drivers’ ability to perceive hazards, and older drivers are at least partially aware of their age-related limitations.     

Oxidation of organic pollutants in aqueous solutions by nanosized copper oxide catalysts

The catalytic activity of copper oxide nanoparticles was investigated for the removal of organic pollutants in aqueous solutions, using hydrogen peroxide as an oxidant. Complete degradation of both alachlor and phenanthrene was achieved after 20 min. The kinetics of the reaction was found to be pseudo-first-order with respect to the pollutant. The influence on the reaction kinetics of different catalyst samples, consisting of the same material but of different origin and different particle properties, was examined. The effects of several factors such as irradiation, oxidant concentration, ionic strength and pH on the reaction were also investigated. The catalysis is not photo-induced and can be performed without UV–vis irradiation. In particular, an optimal oxidant concentration was determined for the studied system. The presence of salts was found to inhibit the alachlor degradation rate. The addition of high concentrations of oxidant or salt results in pseudo-zero-order kinetics. However, NaCl at very high concentrations (>1 M) was found to cause a dramatic increase in reaction rate. The catalysis is efficient over a wide range of pH values.