Lignin and extractives degradation in poplar wood in the presence of hydrogen peroxide and molybdenum polyoxometalated compound

Lignin is an unwanted by-product in bioethanol production from a biomass. The treatment of poplar wood with hydrogen peroxide induces only a decreased amount of extractives and a small reduction in the amount of cellulose in the wood. When the reaction is performed in the presence of H₃PMo₁₂O₄₀, besides the reduction of extractives, an effective decrease in the lignin amount (from 29 to 10%) was observed. A small reduction of the cellulose amount has been observed. When the reaction is performed in the presence of light, a reduction of the efficiency in lignin decomposition has been observed.     

Biometric walk recognizer

This paper presents an approach to gait recognition based on a single consumer accelerometer, built in most present mobile devices. It does not propose a completely novel algorithm, but rather investigates better ways to exploit the Dynamic Time Warping (DTW), which is still one of the most used at present in literature. To this aim, the paper presents both a new segmentation algorithm to split the gait signal into cycles/steps, and investigates the best way to use the possibly segmented signal for recognition. Summarizing, the first contribution of the present work is the proposal of a new segmentation algorithm for the gait signal, which does not require any pre-processing, either interpolation or noise reduction, to enhance the original signal, and its comparison with two other state-of-the-art step segmentation algorithms. The second contribution is related to the extensive tests performed with the five different investigated matching methods. The tests are carried out exploiting all compared segmentation algorithms and three different datasets, collected using different sensors: the originally exploited BWR dataset, that includes walk templates from 30 volunteers, and two huge datasets used for this kind of testing, namely the ZJU-gaitacc and the OU-ISIR Inertial Sensor Database. Tests have been performed in both verification mode, either single-template or multiple-template, and identification mode, both closed and open set. The latter is rarely found in literature though representing the most frequently predictable applicative setting. It is worth underlining that the final goal is to allow using low-cost, built-in sensors that nowadays equip most smartphones. The best result in closed set identification, which is the identification mode usually reported in literature, is achieved using the most constrained method, i.e., limiting the walks in the gallery and in the probe to have a similar number of steps. It reaches ≈93 % of Recognition Rate (RR) on ZJU-gaitacc dataset. The best result obtained with methods exploiting segmentation to overcome the mentioned limitation reaches ≈83 % of Recognition Rate (RR) on the same dataset, using our proposed algorithm. The best results in verification is achieved using multiple templates per user, again without segmentation, with an Equal Error Rate (EER) of 0.09, while the best results with segmentation is achieved again with our algorithm and is and EER of 0.10. This is a very good result for a soft biometrics as gait if often considered. As expected, open set identification achieves lower performance.     

A Differential Approach to Shape from Polarisation: A Level-Set Characterisation

International Journal of Computer Vision - Despite the longtime research aimed at retrieving geometrical information of an object from polarimetric imaging, physical limitations in the polarisation...     

A novel approach for analyzing the food-energy nexus through on-farm energy generation

To find a balance between food and energy security, this research presents the design of an energy self-sufficient farm in electricity, heat and bioethanol, which is produced by energy crops and agricultural residues. The farm proposed is evaluated by two models: Land Optimization and Cost Optimization. Due to the food–fuel debate over land and the detriment of food security, this research proposes utilizing the current abandoned land and increasing the food self-sufficiency ratio (FSSR) of the crops analyzed (rice, wheat and maize). The farm is optimized for several food and fuel demands, with a maximum farm unit size of 100 ha. The result is a myriad of farms of different sizes, each optimized for a certain demand. Subsequently, the amount and variety of such farms are optimized maximizing the food and fuel produced for each city of the case study (Miyagi Prefecture, Japan). The results suggest that the establishment of energy self-sufficient farms in the abandoned land can stimulate the biofuel industry and increase food security simultaneously. The FSSR of maize and wheat can be improved in approximately 10–25 and 7–9 %, respectively. The estimated bioethanol potential is 3.2–3.8 ML. Additionally, a surplus of electricity and heat, approximately 61–65 GWh and 60–165 MJ, respectively, is obtained. As the Land Optimization model proposed is sensitive to crop yields, a simultaneous evaluation is recommended. The results also suggest that the farms must be larger than 8 ha to achieve self-sufficiency; therefore, the policies involved need further evaluation.     

Optimum depth of the information pit on the data surface of a compact disk

Abstract

The substrate of a compact disk with data storage structure (pits and lands) on one side is part of the read-out system. One would not expect the optimum pit depth to be a fixed value (a quarter wavelength, as is customarily assumed) because this value is independent of the parameters of the optical system. The quarter wavelength value is based on an inappropriate plane wave model. A model has been developed, based on the interference of converging spherical waves, for the optimum depth of the information pit on a compact disk. A simple expression was found that gives the dependence of optimum pit depth on parameters of the read-out system. In different systems the optimum pit depth will, in general, differ, ranging from a half wavelength to much smaller values. The results provide a theoretical basis for the optimum design of future systems with higher storage densities. In the present paper, the analysis is extended and several diagrams are presented, which show the dependence of detector signal contrast on system parameters.     

Antioxidative stress therapy with dithiothreitol tetraacetate. I. Protection against carbon tetrachloride induced liver necrosis

Dithiothreitol (DTT) is known to prevent or even reverse several deleterious effects of radiation or of chemical agents operating via free radical and oxidative stress. However, its use has been hampered by its chemical instability and toxic properties. In this work, we synthesized and characterized dithiothreitol tetraacetate (DTT-Ac) which is less toxic and chemically stable, and we provided GLC/MS evidence that it is able to rapidly generate fully deacetylated DTT in liver after its administration to rats. Treatment with DTT-Ac simultaneously with CCl4 or 3 h after the hepatotoxin was able to significantly prevent the CCl4-induced liver necrosis at 24 h after poisoning. DTT-Ac administration was able to significantly reduce the intensity of the covalent binding of CCl4 reactive metabolites to microsomal lipids (CB), but it did not prevent the CCl4-induced initiation of a lipid peroxidation (LP) process as evidenced by diene hyperconjugation of microsomal lipids. Results suggest that DTT-Ac protective effects might be due to its in vivo conversion to DTT which in turn would decrease the intensity of CB via different potential mechanisms to be explored. Protection cannot be attributed to decreases in levels of CCl4 reaching the liver or to chain breaking effects on LP.     

Influence of thermo-vacuum treatment on thermal degradation of various wood species

Solid wood has a certain amount of resistance to fire exposure. Recently, there is also great interest in characterization of the thermal behaviour of treated wood due to increasing demand of such products within the perspective of sustainability of environment. The objective of this study was to evaluate and predict the thermal decomposition process of samples from different wood species, Norway spruce (Picea abies Karst.), common ash (Fraxinus excelsior L.) and Turkey oak (Quercus cerris L.), so that such data can be used for enhanced design of wood products for more effective and better utilization in different applications. Spruce and ash samples were treated at a temperature of 190 °C for 2 h while Turkey oak specimens were steamed at a temperature of 110 °C for 24 h before they were thermally treated at a temperature of 160 °C for 3 h. A thermo-gravimetric analysis of the samples highlighted intraspecific differences in mass loss and the stage of thermal degradation between treated and untreated specimens. The degradation of the wood was characterized by twofold reaction stages, with an exception of Norway spruce samples, which exhibited a one-stage reaction. In addition, thermal treatments affected chemical composition of wood. The obtained results will be helpful in determining the applicability of these materials according to their thermal degradation properties.     

Polymer conformation-assisted wrapping of single-walled carbon nanotube: The impact of cis-vinylene linkage

A soluble π-conjugated polymer cis-PmPV is found to be twice as effective as its trans-PmPV isomer in dispersing SWNTs into organic solvents. The improved efficiency is related to the specific conformation of cis-vinylene-enriched PmPV, which facilitates a planar π-π interaction with SWNT surface and leads to improved nanotube dispersion. ¹H NMR spectra indicate that the cis-CHCH bonds are partially converted to the trans-CHCH, thereby providing necessary conformational cavity for SWNT wrapping. Irradiation triggers a precipitation from SWNT dispersion, providing a purified SWNT/conjugated polymer composite.     

Radical behaviorism and scientific frameworks: From mechanistic to relational accounts.

A substantial portion of Skinner's scholarship was devoted to developing methods and terms for a scientific study of behavior. Three concepts central to scientific accounts (cause, explanation, and theory) are examined to illustrate the distinction between mechanistic and relational frameworks and radical behaviorism's relationship to those frameworks. Informed by a scientific tradition that explicitly rejects mechanistic interpretations, radical behaviorism provides a distinctive stance in contemporary psychology. The present analysis suggests that radical behaviorism makes closer contact with the "new world view" advocated by physicists and philosophers of science than does much of contemporary psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)