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101.
Evolutionary Robotics (ER) is a promising methodology, intended for the autonomous development of robots, in which their behaviors are obtained as a consequence of the structural coupling between robot and environment. It is essential that there be a great amount of interaction to generate complex behaviors. Thus, nowadays, it is common to use simulation to speed up the learning process; however simulations are achieved from arbitrary off-line designs, rather than from the result of embodied cognitive processes. According to the reality gap problem, controllers evolved in simulation usually do not allow the same behavior to arise once transferred to the real robot. Some preliminary approaches for combining simulation and reality exist in the ER literature; nonetheless, there is no satisfactory solution available. In this work we discuss recent advances in neuroscience as a motivation for the use of environmentally adapted simulations, which can be achieved through the co-evolution of robot behavior and simulator. We present an algorithm in which only the differences between the behavior fitness obtained in reality versus that obtained in simulations are used as feedback for adapting a simulation. The proposed algorithm is experimentally validated by showing the successful development and continuous transference to reality of two complex low-level behaviors with Sony AIBO1 robots: gait optimization and ball-kicking behavior. 1AIBO is a trademark of Sony Corporation  相似文献   
102.
Data from recent studies conducted in rodent models and humans suggest that interleukin-17A (IL-17A) plays a role in the induction of inflammation in adipose tissue during obesity. The aim of this study was to assess the gene expression of IL-17A in adipose tissue of morbidly obese patients. We used RT-PCR to evaluate the expression of IL-17A and several adipo/cytokines in the visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) of 10 normal-weight control women (BMI < 25 kg/m2) and 30 morbidly obese women (MO, BMI > 40 kg/m2). We measured serum levels of IL-17A and adipo/cytokines in MO and normal weight women. IL-17A expression was significantly higher in VAT than in SAT in MO patients (p = 0.0127). It was very low in normal-weight controls in both VAT and SAT tissues. We found positive correlations between IL-17A and IL-6, lipocalin-2 and resistin in VAT of MO patients. The circulating level of IL-17A was higher in the normal-weight group than the MO patients (p = 0.032), and it was significantly related to adiponectin and TNFRII levels. In conclusion, IL-17A expression in VAT is increased in morbidly obese women, which suggests a link between obesity and innate immunity in low-grade chronic inflammation in morbidly obese women.  相似文献   
103.
In this research, we describe the application of the complexes o‐C6H4(NSiMe3)2ZrCl2 ( 1 ), o‐C6H4(NSiMe3)2TiBr2 ( 2 ), o‐C6H4(NSiMe3)2TiCl2 ( 3 ), C2H4(NSiMe3)2ZrCl2 ( 4 ), in the ethylene polymerization with different Al/M ratios and temperatures. These complexes presented significant catalytic activities in the presence of methyaluminoxane (MAO) as cocatalyst and toluene as solvent, producing high molecular weight linear polyethylenes. Zirconium complexes were more active at 60°C and titanium complexes at 40°C. Zirconium complex ( 1 ) showed the best values of activity (347 kg PE/mol Zr h atm) for Al/Zr ratio of 340 and 60°C of temperature. In ethylene‐1‐hexene copolymerization, the best result was also reached with catalyst 1 , at the same conditions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
104.
Contamination of shellfish with lipophilic marine biotoxins (LMB), pectenotoxins (PTXs), yessotoxins (YTXs) and okadaic acid (OA) toxin groups in southern Chile is a constant challenge for the development of miticulture considering the high incidence of toxic episodes that tend to occur. This research is focused on using methodologies for assessing the decrease in toxins of natural resources in Chile with high value, without altering the organoleptic properties of the shellfish. The species were processed through steaming (1 min at 121°C) and subsequent canning (5 min at 121°C). Changes in the profiles of toxins and total toxicity levels of LMB in endemic bivalves and gastropods were determined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The total reduction of toxicity (≈ 15%) was not related to the destruction of the toxin, but rather to the loss of LMB on removing the shells and packing media of canned products (***p < 0.001). Industrial processing of shellfish reduces LMB contents by up to 15% of the total initial contents, concomitant only with the interconversion of PTX-group toxins into PTX-2sa. In soft bottom-dwelling species with toxicities beyond the standard for safe human consumption (≥ 160 μg OA-eq kg1), toxicity can be reduced to safe levels through industrial preparation procedures.  相似文献   
105.
The general transmissivity law of ground vibrations was studied, and a user-friendly methodology for determining the behavior of vibrations generated in any rock mass is proposed. The study was based on a single blast in a trench excavation, analyzing the vibration components recorded from two fixed locations. The attenuation law and the main variables according to the legal requirements, frequency and peak particle velocity (PPV), are defined with this novel method, achieving a high confidence level in a simple manner. The proposed approach can also have an important impact in terms of reducing the potential consequences of vibrations for the surrounding construction and achieving the required definition of rock mass. Reducing the cost and time in many projects where blasting techniques are applied is particularly useful for the design of future blasts.  相似文献   
106.
International Journal of Information Security - Pollution attacks are one of the major concerns facing P2P networks. They have a tremendous impact on push-based fully connected overlays, in which...  相似文献   
107.
New cases of blue cheese discoloration has led to recent research to identify the causal agent and factors that favor blue pigment appearing. Nonetheless, very few reports have described the source of contamination and the measurements to eradicate the microbiological source on cheese farms by determining the relation between blue discoloration on fresh cheese and the Pseudomonas fluorescens group. Thus, 60 samples from a cheese farm (cheese, equipment surfaces, tap water, and raw and pasteurized milk) were analyzed by phenotypical, MALDI-TOF, 16S rRNA sequencing and pulsed-field gel electrophoresis tests to determine the causal agent. The results obtained by pulsed-field gel electrophoresis with restriction enzymes XbaI and SpeI confirmed tap water as the initial contaminated source. The above-mentioned result was essential to avoid Pseudomonas contamination due to the most residual microorganisms being inactivated through a new disinfection program.  相似文献   
108.
109.
Halophilic micro‐organisms are able to survive in high salt concentrations because they have developed diverse biochemical, structural and physiological modifications, allowing the catalytic synthesis of proteins with interesting physicochemical and structural properties. The main characteristic of halophilic enzymes that allows them to be considered as a novel alternative for use in the biotechnological industries is their polyextremophilicity, i.e. they have the capacity to be thermostable, tolerate a wide range of pH, withstand denaturation and tolerate high salt concentrations. However, there have been relatively few studies on halophilic enzymes, with some being based on their isolation and others on their characterisation. These enzymes are scarcely researched because attention has been focused on other extremophile micro‐organisms. Only a few industrial applications of halophilic enzymes, principally in the fermented food, textile, pharmaceutical and leather industries, have been reported. However, it is important to investigate applications of these enzymes in more biotechnological processes at both the chemical and the molecular level. This review discusses the modifications of these enzymes, their industrial applications and research perspectives in different biotechnological areas. Copyright © 2012 Society of Chemical Industry  相似文献   
110.
Two experiments were carried out to compare mechanical milking in mid-level (ML) and low-level (LL) milkline in goats. The first trial used 40 intramammary infection (IMI)-free goats that had been milked in ML during a pre-experimental period of 4±1 weeks post partum. These animals were divided into two groups (n=20), randomly assigning each group to ML or LL milking for a 17-week experimental period. During this period, several strategies were applied to increase teat exposure to pathogens in both experimental groups. The IMI rate was the same in both experimental groups (30% of goats), although the majority of new infections appeared earlier in ML (weeks 1-5) than in LL (weeks 7-16). Teat-end vacuum range (maximum minus minimum vacuum) was higher in ML than in LL, but no significant differences were found in the remaining variables [milk production and composition, somatic cell count (SCC), frequency of liner slips+teatcups fall off]. In the second experiment, in a crossover design (54 goats in fourth month of lactation; 2 treatments, ML and LL, in 2 experimental periods each lasting 1 week) it was observed that both the milk fractioning (reduced machine milk and increased machine stripping) and average machine milk flow worsened slightly in ML milking; in contrast, no differences were observed in total milking time or teat thickness changes after milking. It was concluded that the differences found between ML and LL are not sufficiently important to discourage breeders from using ML in goat milking.  相似文献   
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