Microorganisms are of central importance in the biodeterioration of wood by wood-boring organisms in marine habitats. We have demonstrated that shipworms attack wood that has been pre-conditioned by microbial degradation. Apparently the microorganisms function by either triggering metamorphosis or releasing an essential nutrient from the wood. We have shown that the crustacean wood-borer, Limnoria, lacks a digestive tract microflora, while the borer exoskeleton is densely colonized by bacteria. It is probable that these organisms, living in a nitrogen deficient environment on wood, use bacteria in wood and on their exoskeletonsas a nitrogen source. We are currently studying the role of bacteria in the development and survival of other wood-boring organisms. Our efforts are directed at development of effective targeted chemicals for control of wood-borers.

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Tremor is the most common of all involuntary movement. A lot of tremor patients in upper limb have serious difficulties performing daily living activities. We have developed the exoskeleton robot for tremor patient. In this paper, we focused on to develop a signal processing method to extract the voluntary movement from the electromyogram (EMG) signal in which the voluntary movement and tremor were mixed. We have researched about following two methods to recognize the voluntary movement: one is low pass filter and neural network (NN), the other is short time Fourier transform and NN. The low pass filter and neural network (NN) were effective for recognition of healthy subject’s movement. However, these methods were not applied to the tremor patient’s movement due to the characteristic oscillation of the EMG signal in the tremor patient. The proposed algorithm, which was composed of the short time Fourier transform and NN, dramatically improved the recognition rate of tremor patient’s movement. It was confirmed that the signal processing using STFT and NN is suitable for the recognition of the tremor patients. In future, we will develop more accurate algorithm based on this study, and finally conduct the clinical test to show effectiveness of our system.

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This paper is concerned with a control method of an exoskeletal ankle based on surface electromyographic (sEMG) signals. The sEMG signals of human ankle are introduced first. The muscles which are medial gastrocnemius(MG) and tibialis anterior(TA) are selected by experiments. Then a threshold method of controlling the exoskeletal ankle using sEMG signals is designed. A control system is realized. The sEMG signals are acquired, and sent to the computer. The computer deals with the sEMG signals and generates the control orders. The control orders are passed to the motor controller and drive the exoskeleton to move. At last, through experiment, the control method is verified and the effectiveness of the control system is proved.

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Chitin, extracted primarily from exoskeleton shellfish, is one of the most abundant biopolymer in the world. It is estimated to be produced annually almost as much as cellulose. The development of fishing activities in Morocco (coastline of 3500 km on both the Atlantic and the Mediterranean) induced an important fish industry waste. The aim of this work is to recover chitin, extracted from shellfish waste, and chitosan, produced by deacetylation of chitin, in the adsorption of organic pesticide 2,4-dichlorophenoxyacetate (2,4-D). The chitosan samples were prepared from α-chitin from crustacean shells and β-chitin from squid pens. The chitin deacetylation was carried out according to two methods using, respectively, as alkaline agent, the aqueous sodium hydroxide solution and anhydrous potassium hydroxide. The role of the source and of the process on the N-deacetylation reactions is confirmed. Characterization of chitin and chitosan was performed by infrared spectroscopy and nuclear magnetic resonance. The adsorption of 2,4-D by chitin and chitosan was performed at different pH values, the pesticide-adsorbent contact time and initial pesticide concentration. The adsorption is described by Langmuir-type isotherm and Freundlich-type isotherm. Recovery tests of 2,4-D confirm the initial interest in using chitin and chitosan as a depolluting agent.

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The work presents a newly developed safety concept for application of robotic walking simulators based on the principle of programmable footplates in gait rehabilitation. Unlike robotic hand devices or exoskeleton robots for gait training on treadmills, which can be built relatively lightweight and require only small drives which can hardly do harm to the patient, a programmable footplate walking simulator with permanent foot fixture essentially needs to have powerful drives in order to carry and move the full body weight of the patient. The developed safety concept comprises several redundant algorithms and devices in the real-time robot control software, electrical emergency stop circuitry and machine mechanics. The mechanical core is a machine design offering maximum passive security by covering all moving parts (i.e. robot drives and linkages) and a newly developed foot safety release binding, which is mounted on each footplate. The release binding allows a safe release from the footplate in all directions in any degree of freedom in the sagittal plane. It is combined with an ankle goniometer which is equipped with adjustable emergency stop limit switches, thus ensuring that the allowed ankle range-of-motion is not exceeded.

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