A comparative analysis of scoring methods for chemical discrimination of prey by squamate reptiles

In studies of squamate responses to prey chemicals presented on cotton-tipped applicators, investigators typically record several responses, each of which gives only part of the overall picture. The tongue-flick/attack score (TFAS) is a widely used composite measure of response strength that accounts for attack, its latency, and number of tongue-flicks. We present data and analyses on these variables and investigate the utility of several other possible response variables. It is concluded, for both practical and theoretical reasons, that TFAS and two modifications of it are the best measures of response strength. Uses and statistical analyses of TFAS and variables derived from it are discussed. It is recommended that information on tongue-flick rate, number of individuals attacking, and latency to attack be presented.     

The ophiophage defensive response in crotaline snakes: Extension to new taxa

A total of 21 new taxa of New World pit vipers (Serpentes: Crotalinae) responded by elevating the middle portion of the body in a defensive posture (body bridge) when exposed to the skin substances of certain colubrid snakes (Colubridae). Newborn snakes from two of the three species tested gave the response. Several new species of colubrid snakes also are documented as capable of eliciting a response, and it is suggested that the termophiophage defensive response be used to denote body bridging and associated defensive behaviors instead of the restrictive kingsnake defense posture. Most of the snakes which elicit the response in crotaline snakes are known to feed on lizards and/or snakes. There is no apparent correlation between the stimulus snakes' ability to elicit a response in the crotaline snakes and sympatry with the crotaline snakes.     

Analysis of chemicals from earthworms and fish that elicit prey attack by ingestively naive garter snakes (Thamnophis)

Materials previously shown to elicit increased tongue-flicking and prey attack in garter snakes (Thamnophis sirtalis) were isolated from both earthworms (Lumbricus terrestris) and fish (Pimephales promelas). Both high- and low-molecular-weight components from earthworms and fish stimulated attacks and increased tongue-flicking in previously unfed neonate garter snakes relative to distilled water controls. Earthworm collagen was also effective, but even concentrated fractions were less effective than raw extract. Conflicting reports on the effectiveness of collagen suggest that the salient chemical(s) is a smaller molecule tightly bound to collagen and resisting standard purification methods.     

Characterization of the skin orientation of thermotropic liquid‐crystalline copolyester moldings with near‐edge X‐ray absorption fine structure

The process of injection‐molding net‐shape parts from thermotropic liquid‐crystalline polymers results in a skin‐core macrostructure. The underlying orientation in the core and the skin may differ both in magnitude and direction. A combination of near‐edge X‐ray absorption fine structure (NEXAFS) spectroscopy and two‐dimensional wide‐angle X‐ray scattering (2D WAXS) in transmission was used to characterize the orientation in injection‐molded plaques fabricated from thermotropic liquid‐crystalline copolyesters based on either 4,4′‐dihydroxy‐α‐methylstilbene or 6‐hydroxy‐2‐naphthoic acid/6‐hydroxybenzoic acid. NEXAFS is presented as a noninvasive in situ means of determining surface layer orientation that samples to a depth of as little as 2 nm and does not require slicing or ultramicrotoming of the samples. The effects of various processing conditions on the surface orientation in the region of the centerline of square injection‐molded plaques are presented and discussed. Comparisons are made between orientation parameters obtained by 2D WAXS in transmission, which is dominated by the microstructure in the core, and the NEXAFS technique. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2473–2480, 2005     

Ice particles trapped by temperature gradients at mbar pressure

In laboratory experiments we observe that ice particles (≤100 μm) entrained in a low pressure atmosphere (~1 mbar) get trapped by temperature gradients between three reservoirs at different temperature. Confining elements are a peltier element at 250 K (bottom), a liquid nitrogen reservoir at 77 K (top), and the surrounding vacuum chamber at 293 K. Particle levitation and trapping is modeled by an interplay of thermophoresis, photophoresis, and gravity. A number of ice particles are trapped simultaneously in close spatial distance to each other at least up to minutes and are accessible for further experiments.     

Re-identification of Smart Meter data

The Smart Grid approach enhances the power grid with information technology. Smart Meters are an important part of the Smart Grid. They record the energy consumption of households with a high-resolution and transfer consumption records to the energy provider in real time. Since they allow to infer personal information like the daily routine of the household members, Smart Meters are also a promising source for lifelogging. However, in liberalized energy markets, many different parties have access to these data. This puts the privacy of consumers at risk. In this paper, we analyze to which degree Smart Meter data, as collected by our industry partner, can be linked to its producer, using simple statistical measures. We devise features of the energy consumption, for example, the first peak of demand in the morning, and we describe an analytical framework that quantifies how well these features can identify households. Finally, we conduct a study with 60,480 energy-consumption records from 180 households. Our study shows that 68 % of the records can be re-identified with simple means already. This insight is important for Smart Grids, as it emphasizes the need for research and use of anonymization techniques for the Smart Grid.     

Methodology for evaluating automated map generalization in commercial software

This paper presents a methodology developed for a study to evaluate the state of the art of automated map generalization in commercial software without applying any customization. The objectives of this study are to learn more about generic and specific requirements for automated map generalization, to show possibilities and limitations of commercial generalization software, and to identify areas for further research. The methodology had to consider all types of heterogeneity to guarantee independent testing and evaluation of available generalization solutions. The paper presents the two main steps of the methodology. The first step is the analysis of map requirements for automated generalization, which consisted of sourcing representative test cases, defining map specifications in generalization constraints, harmonizing constraints across the test cases, and analyzing the types of constraints that were defined. The second step of the methodology is the evaluation of generalized outputs. In this step, three evaluation methods were integrated to balance between human and machine evaluation and to expose possible inconsistencies. In the discussion the applied methodology is evaluated and areas for further research are identified.     

A Fast and Self-Acting Release-Caging-Mechanism for Actively Driven Drop Tower Systems

Today’s and future scientific research programs ask for high quality microgravity conditions of 10^?6 g on ground combined with high repetition rates of 100 flights per day or more. Accordingly, a new type of drop tower, the GraviTower Bremen, (GTB), has been suggested and is currently under development. As a first stage of development, a GTB-Prototype (GTB-Pro) has been designed which uses an active rope drive to accelerate a slider/drag shield and an experiment therein on a vertical parabola. During the free fall phase, the experiment is decoupled from the slider by a self-acting Release-Caging-Mechanism (RCM). Our prototype will provide 2.5 s of microgravity for experiments of up to 500 kg for at least 100 times per day. In this article, the final concept of the engineering of the active rope drive and the RCM are presented in detail. Based on extensive simulations aiming at an optimization of the whole system we developed a hydraulic rope drive system with minimized vibrational amplitude and low number of eigenfrequencies. The RCM achieves a very fast (≤ 0.1 s) self-acting release of the experiment from the slider by making use of the dynamics of the hydraulic rope drive. Furthermore, passive hydraulic stop dampers in the RCM build a passive and self-acting recoupling mechanism. This system is optimized for a fast decoupling to compensate for the time limitation posed by the chosen drive technology. The simulations included a comparison of different drive technologies, physical effects like the Coriolis force, and the dynamics of the RCM system itself.     

Study on interfacial adhesion strength of single glass fibre/polypropylene model composites by altering the nature of the surface of sized glass fibres

Polypropylene (PP) compatibly sized glass fibres (GFs) were treated with boiling water and toluene, respectively, to reveal the interactions of water and toluene with different components in the sizing of sized GF and their influences on the interfacial adhesion strength of GF/PP model composites. Compared to control GF/PP model composites, about 30% increase of interfacial adhesion strength was achieved for composites with water-treated GF, whereas a small decrease of interfacial adhesion strength was revealed for composites with toluene-treated GF. X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Zeta-potential measurement, and water contact angle measurement demonstrated that the boiling water-treated GFs posses a more polar and hydrophilic surface with homogeneously distributed derivatives of 3-aminopropyltriethoxysilane, which is related to a higher interfacial adhesion strength for water-treated GF/PP model composites. In contrast, hot toluene-treated GFs led to a more hydrophobic surface with low molar mass PP and surfactants enriching on the outermost surface.