Application of extracts from the poisonous plant, Nerium Oleander L., as a wood preservative

The antifungal properties of poisonous plant extracts from oleanders (Nerium oleander L.) were determined when used as a wood preservative. The extract was prepared from oleanders leaves andflowers in 96% ethyl alcohol. The wood blocks of Turkish oriental beech (Fagus orientalis L.) and Scots pine (Pinus sylvestris L.) were impregnated with the extracts. The abilities of the extract to suppressattack by Postia placenta (Fr.) (brown rot) and Trametes versicolor (L: Fr.) Quel. (a white-rot) was investigated. Treated blocks were exposed to P. placenta and T. versicolor attacks for 12 weeks by following the soil-block method. While untreated wood specimens have weight loss ranging between 27.37 and 30.66% for P. placenta and 8.64 and 24.06% for T. versicolor, the wood treated with theextracts is of weight loss between 5.54 and 10.98% for P. placenta, and between 5.02 and 28.25% for T. versicolor. The lowest weight loss was found to be for beech wood (5.02%) impregnated with the extractof oleander at a concentration level of 0.25% against T. versicolor. While the highest weight loss was also on the beech wood (28.25%) treated with the same extract at the level of 0.50% concentrationagainst T. versicolor. In conclusion, the extracts could be used as effective wood preservative

Introduction and evaluation of the wood preservative potentials of the poisonous Sternbergia candidum extracts

The ability of Sternbergia candida (SB Candidum Mathew.) extract to suppress attack by Postia placenta (Fries) M. Larsen et Lombard (Mad 698), (a brown-rot) and Trametes versicolor (L.ex Fr.) Quel.(a white-rot) was investigated. The extract was dissolved from Sterinbergia Candidum’s bulb and leaves in 96% ethyl alcohol. Poisonous extract impregnated into wood blocks of Turkish oriental beech (Fagus orientalis L.) and Scots pine (Pinus sylvestris L.). Extract dosages were 0.25, 0.75, 1.50 and 3.00%. Treated blocks were exposed to P. placenta and T. versicolor attack for 12 weeks by the soil block method. Only extract dosages of 0.25 and 0.75% were found efficacious in suppressing attack. A tukey studentized test found both dosages significant at 5% level. In conclusion, the poisonous extracts could be used as effective wood preservative when concentration was adjusted

Transmission enhancement through deep subwavelength apertures using connected split ring resonators

Cataloged from PDF version of article.We report astonishingly high transmission enhancement factors through a subwavelength aperture at microwave frequencies by placing connected split ring resonators in the vicinity of the aperture. We carried out numerical simulations that are consistent with our experimental conclusions. We experimentally show higher than 70,000-fold extraordinary transmission through a deep subwavelength aperture with an electrical size of lambda/31x lambda/12 (width x length), in terms of the operational wavelength. We discuss the physical origins of the phenomenon. Our numerical results predict that even more improvements of the enhancement factors are attainable. Theoretically, the approach opens up the possibility for achieving very large enhancement factors by overcoming the physical limitations and thereby minimizes the dependence on the aperture geometries. (C) 2010 Optical Society of Americ

PATIKAmad: Putting microarray data into pathway context

High-throughput experiments, most significantly DNA microarrays, provide us with system-scale profiles. Connecting these data with existing biological networks poses a formidable challenge to uncover facts about a cell's proteome. Studies and tools with this purpose are limited to networks with simple structure, such as protein-protein interaction graphs, or do not go much beyond than simply displaying values on the network. We have built a microarray data analysis tool, named PATIKAmad, which can be used to associate microarray data with the pathway models in mechanistic detail, and provides facilities for visualization, clustering, querying, and navigation of biological graphs related with loaded microarray experiments. PATIKAmad is freely available to noncommercial users as a new module of PATIKAweb at http://web.patika.org. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA

Strength Development in Overmolded Structures

Overmolding of thermoplastic composites is a technology in which a thermoplastic composite is thermoformed and subsequently injection overmolded. Although the feasibility of the process is increasingly demonstrated, it is acknowledged that there is a lack of proper design tools that can be used for a right-the-first-time design strategy. Here, a modelling strategy is proposed for the prediction of the bond strength between a composite insert and an injected polymer. The development of the interface strength is affected by the process history as well, where the temperature and polymer chain mobility play an important role. In the model, the melting behavior of the polymer interface is described using the temperature evolution on the interface combined with experimentally determined polymer melting kinetics via flash differential scanning calorimetry (DSC). Dedicated test geometries were developed and manufactured to evaluate the bond strength under different loading conditions. Short beam strength experiments were used to study the flow length dependency of the interface strength and were correlated with the predicted melting evolution on the interface. The outcome was critically reviewed leading to preliminary guidelines for design, materials and processing as well as routes to further mature this technology

Switching Frequency Effects on the Efficiency and Harmonic Distortion in a Three-Phase Five-Level CHBMI Prototype with Multicarrier PWM Schemes: Experimental Analysis

The current climatic scenario requires the use of innovative solutions to increase the production of electricity from renewable energy sources. Multilevel Power Inverters are a promising solution to improve the penetration of renewable energy sources into the electrical grid. Moreover, the performance of MPIs is a function of the modulation strategy employed and of its features (modulation index and switching frequency). This paper presents an extended and experimental analysis of three-phase five-level Cascaded H-Bridges Multilevel Inverter performance in terms of efficiency and harmonic content considering several MC PWM modulation strategies. In detail, the CHBMI performance is analyzed by varying the modulation index and the switching frequency. For control purposes, the NI System On Module sbRIO-9651 control board, a dedicated FPGA-based control board for power electronics and drive applications programmable in the LabVIEW environment, is used. The paper describes the modulation strategies implementation, the test bench set-up, and the experimental investigations carried out. The results obtained in terms of Total Harmonic Distorsion (THD) and efficiency are analyzed, compared, and discussed

Multiple Projection Optical Diffusion Tomography with Plane Wave Illumination

We describe a new data collection scheme for optical diffusion tomography in which plane wave illumination is combined with multiple projections in the slab imaging geometry. Multiple projection measurements are performed by rotating the slab around the sample. The advantage of the proposed method is that the measured data can be much more easily fitted into the dynamic range of most commonly used detectors. At the same time, multiple projections improve image quality by mutually interchanging the depth and transverse directions, and the scanned (detection) and integrated (illumination) surfaces. Inversion methods are derived for image reconstructions with extremely large data sets. Numerical simulations are performed for fixed and rotated slabs

Executive compensation structure and the motivations for seasoned equity offerings

We hypothesize that managers who receive high equity-based compensation have greater incentive to avoid ownership dilution by timing their seasoned equity offers to periods when investors temporarily overvalue their stock. We provide empirical support for this hypothesis using a measure of equity-based compensation that reflects the sensitivity of the top five executives' wealth (based on ownership of stock, options, and restricted shares) to a 1% change in stock price. We find that firms associated with high equity-based compensation for top executives experience abnormally low stock returns and relatively unfavorable changes in operating performance in the three-year period following the issue. Overall, the findings support the premise that managers whose wealth is most sensitive to stock price changes are more likely to act in the interest of current shareholders by issuing equity when they believe their stock is overvalued

Automated Prediction of CMEs Using Machine Learning of CME – Flare Associations

YesIn this work, machine learning algorithms are applied to explore the relation between significant flares and their associated CMEs. The NGDC flares catalogue and the SOHO/LASCO CMEs catalogue are processed to associate X and M-class flares with CMEs based on timing information. Automated systems are created to process and associate years of flares and CMEs data, which are later arranged in numerical training vectors and fed to machine learning algorithms to extract the embedded knowledge and provide learning rules that can be used for the automated prediction of CMEs. Different properties are extracted from all the associated (A) and not-associated (NA) flares representing the intensity, flare duration, duration of decline and duration of growth. Cascade Correlation Neural Networks (CCNN) are used in our work. The flare properties are converted to numerical formats that are suitable for CCNN. The CCNN will predict if a certain flare is likely to initiate a CME after input of its properties. Intensive experiments using the Jack-knife techniques are carried out and it is concluded that our system provides an accurate prediction rate of 65.3%. The prediction performance is analysed and recommendation for enhancing the performance are provided

Diffusion of particles moving with constant speed

The propagation of light in a scattering medium is described as the motion of a special kind of a Brownian particle on which the fluctuating forces act only perpendicular to its velocity. This enforces strictly and dynamically the constraint of constant speed of the photon in the medium. A Fokker-Planck equation is derived for the probability distribution in the phase space assuming the transverse fluctuating force to be a white noise. Analytic expressions for the moments of the displacement $$ along with an approximate expression for the marginal probability distribution function $P(x,t)$ are obtained. Exact numerical solutions for the phase space probability distribution for various geometries are presented. The results show that the velocity distribution randomizes in a time of about eight times the mean free time ($8t^*$) only after which the diffusion approximation becomes valid. This factor of eight is a well known experimental fact. A persistence exponent of $0.435 \pm 0.005$ is calculated for this process in two dimensions by studying the survival probability of the particle in a semi-infinite medium. The case of a stochastic amplifying medium is also discussed.Comment: 9 pages, 9 figures(Submitted to Phys. Rev. E