868 resultados para turn-taking


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The protection of the fundamental human values (life, bodily integrity, human dignity, privacy) becomes imperative with the rapid progress in modern biotechnology, which can result in major alterations in the genetic make-up of organisms. It has become possible to insert human genes into pigs so that their internal organs coated in human proteins are more suitable for transplantation into humans (xenotransplantation), and micro-organisms that cam make insulin have been created, thus changing the genetic make-up of humans. At the end of the 1980s, the Central and Eastern European (CEE) countries either initiated new legislation or started to amend existing laws in this area (clinical testing of drugs, experiments on man, prenatal genetic diagnosis, legal protection of the embryo/foetus, etc.). The analysis here indicates that the CEE countries have not sufficiently adjusted their regulations to the findings of modern biotechnology, either because of the relatively short period they have had to do so, or because there are no definite answers to the questions which modern biotechnology has raised (ethical aspects of xenotransplantation, or of the use of live-aborted embryonic or foetal tissue in neuro-transplantation, etc.). In order to harmonise the existing regulations in CEE countries with respect to the EU and supranational contexts, two critical issues should be taken into consideration. The first is the necessity for CEE countries to recognise the place of humans within the achievements of modern biotechnology (a broader affirmation of the principle of autonomy, an explicit ban on the violation of the genetic identity of either born or unborn life, etc.). The second concerns the definition of the status of different biotechnological procedures and their permissibility (gene therapy, therapeutic genomes, xenotransplantation, etc.). The road towards such answers may be more easily identified once all CEE countries become members of the Council of Europe and express their wish to join the EU, which in turn presupposes taking over the entire body of EU legislation.

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During locomotion, turning is a common and recurring event which is largely neglected in the current state-of-the-art ankle-foot prostheses, forcing amputees to use different steering mechanisms for turning, compared to non-amputees. A better understanding of the complexities surrounding lower limb prostheses will lead to increased health and well-being of amputees. The aim of this research is to develop a steerable ankle-foot prosthesis that mimics the human ankle mechanical properties. Experiments were developed to estimate the mechanical impedance of the ankle and the ankles angles during straight walk and step turn. Next, this information was used in the design of a prototype, powered steerable ankle-foot prosthesis with two controllable degrees of freedom. One of the possible approaches in design of the prosthetic robots is to use the human joints’ parameters, especially their impedance. A series of experiments were conducted to estimate the stochastic mechanical impedance of the human ankle when muscles were fully relaxed and co-contracting antagonistically. A rehabilitation robot for the ankle, Anklebot, was employed to provide torque perturbations to the ankle. The experiments were performed in two different configurations, one with relaxed muscles, and one with 10% of maximum voluntary contraction (MVC). Surface electromyography (sEMG) was used to monitor muscle activation levels and these sEMG signals were displayed to subjects who attempted to maintain them constant. Time histories of ankle torques and angles in the lateral/medial (LM) directions, inversion-eversion (IE), and dorsiflexionplantarflexion (DP) were recorded. Linear time-invariant transfer functions between the measured torques and angles were estimated providing an estimate of ankle mechanical impedance. High coherence was observed over a frequency range up to 30 Hz. The main effect of muscle activation was to increase the magnitude of ankle mechanical impedance in all degrees of freedom of the ankle. Another experiment compared the three-dimensional angles of the ankle during step turn and straight walking. These angles were measured to be used for developing the control strategy of the ankle-foot prosthesis. An infrared camera system was used to track the trajectories and angles of the foot and leg. The combined phases of heel strike and loading response, mid stance, and terminal stance and pre-swing were determined and used to measure the average angles at each combined phase. The Range of motion (ROM) in IE increased during turning while ML rotation decreased and DP changed the least. During the turning step, ankle displacement in DP started with similar angles to straight walk and progressively showed less plantarflexion. In IE, the ankle showed increased inversion leaning the body toward the inside of the turn. ML rotation initiated with an increased medial rotation during the step turn relative to the straight walk transitioning to increased lateral rotation at the toe off. A prototype ankle-foot prosthesis capable of controlling both DP and IE using a cable driven mechanism was developed and assessed as part of a feasibility study. The design is capable of reproducing the angles required for straight walk and step turn; generates 712N of lifting force in plantarflexion, and shows passive stiffness comparable to a nonload bearing ankle impedance. To evaluate the performance of the ankle-foot prosthesis, a circular treadmill was developed to mimic human gait during steering. Preliminary results show that the device can appropriately simulate human gait with loading and unloading the ankle joint during the gait in circular paths.

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The generic approach of the Spine Tango documentation system, which uses web-based technologies, is a necessity for reaching a maximum number of participants. This, in turn, reduces the potential for customising the Tango according to the individual needs of each user. However, a number of possibilities still exist for tailoring the data collection processes to the user's own hospital workflow. One can choose between a purely paper-based set-up (with in-house scanning, data punching or mailing of forms to the data centre at the University of Bern) and completely paper-free online data entry. Many users work in a hybrid mode with online entry of surgical data and paper-based recording of the patients' perspectives using the Core Outcome Measures Index (COMI) questionnaires. Preoperatively, patients can complete their questionnaires in the outpatient clinic at the time of taking the decision about surgery or simply at the time of hospitalisation. Postoperative administration of patient data can involve questionnaire completion in the outpatient clinic, the handing over the forms at the time of discharge for their mailing back to the hospital later, sending out of questionnaires by post with a stamped addressed envelope for their return or, in exceptional circumstances, conducting telephone interviews. Eurospine encourages documentation of patient-based information before the hospitalisation period and surgeon-based information both before and during hospitalisation; both patient and surgeon data should be acquired for at least one follow-up, at a minimum of three to six months after surgery. In addition, all complications that occur after discharge, and their consequences should be recorded.

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Transforming growth factor-beta2 (TGF-beta2) stimulates the expression of pro-fibrotic connective tissue growth factor (CTGF) during the course of renal disease. Because sphingosine kinase-1 (SK-1) activity is also upregulated by TGF-beta, we studied its effect on CTGF expression and on the development of renal fibrosis. When TGF-beta2 was added to an immortalized human podocyte cell line we found that it activated the promoter of SK-1, resulting in upregulation of its mRNA and protein expression. Further, depletion of SK-1 by small interfering RNA or its pharmacological inhibition led to accelerated CTGF expression in the podocytes. Over-expression of SK-1 reduced CTGF induction, an effect mediated by intracellular sphingosine-1-phosphate. In vivo, SK-1 expression was also increased in the podocytes of kidney sections of patients with diabetic nephropathy when compared to normal sections of kidney obtained from patients with renal cancer. Similarly, in a mouse model of streptozotocin-induced diabetic nephropathy, SK-1 and CTGF were upregulated in podocytes. In SK-1 deficient mice, exacerbation of disease was detected by increased albuminuria and CTGF expression when compared to wild-type mice. Thus, SK-1 activity has a protective role in the fibrotic process and its deletion or inhibition aggravates fibrotic disease.

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