2,276 research outputs found
The AISB’08 Symposium on Multimodal Output Generation (MOG 2008)
Welcome to Aberdeen at the Symposium on Multimodal Output Generation (MOG 2008)! In this volume the papers presented at the MOG 2008 international symposium are collected
Evolution of YidC/Oxa1/Alb3 insertases: three independent gene duplications followed by functional specialization in bacteria, mitochondria and chloroplasts
Members of the YidC/Oxa1/Alb3 protein family facilitate the insertion, folding and assembly of proteins of the inner membranes of bacteria and mitochondria and the thylakoid membrane of plastids. All homologs share a conserved hydrophobic core region comprising five transmembrane domains. On the basis of phylogenetic analyses, six subgroups of the family can be distinguished which presumably arose from three independent gene duplications followed by functional specialization. During evolution of bacteria, mitochondria and chloroplasts, subgroup-specific regions were added to the core domain to facilitate the association with ribosomes or other components contributing to the substrate spectrum of YidC/Oxa1/Alb3 proteins
To pool or not to pool in hospitals: a theoretical and practical comparison for a radiotherapy outpatient department
This paper examines whether urgent and regular patients waiting for a consultation at a radiotherapy outpatient department should be pooled or not. Both queuing theory and discrete event simulation were applied to a realistic case study. The theoretical approach shows that pooling is not always beneficial with regard to the waiting times of urgent patients. Furthermore, the practical approach indicates that the separation of queues may require less capacity to meet the waiting time performance target for urgent as well as regular patients. The results seem to be of general interest for hospital
TIPS for Scaling up Research in Upper Limb Prosthetics
Many research initiatives have been employed in upper limb prosthetics (ULP) in the last few decades. The body of knowledge is growing and inspired by new and interesting technology that has been brought to the market to facilitate functioning of people with upper limb defects. However, a lot of research initiatives do not reach the target population. Several reasons can be identified as to why research does not move beyond the lab, such as lack of research quality, disappointing results of new initiatives, lack of funding to further develop promising initiatives, and poor implementation or dissemination of results. In this paper, we will appraise the current status of the research in ULP. Furthermore, we will try to provide food for thought to scale up research in ULP, focusing on (1) translation of research findings, (2) the quality of innovations in the light of evidence-based medicine and evidence-based practice, (3) patient involvement, and (4) spreading of research findings by focusing on implementation and dissemination of results and collaboration in a national and international perspective. With this paper, we aim to open the discussion on scaling up research in the community of professionals working in the field of ULP
Of Mice and Mucins: Models for studying the role of mucins in the intestine
The small intestine is the major organ for the absorption of nutrients and also
secretes enzymes to complete the digestive processes started in the stomach1-5. A 30-
50% loss (remaining length, <75 cm in children and <200 cm in adults) often leads to
malabsorption, with resultant severe diarrhea, dehydration, electrolyte imbalances,
nutrient deficiencies and weight loss6, 7. The small intestine from proximal to distal
is divided into the duodenum, jejunum, and ileum. The lining of the small intestine
is a single-layered epithelium. It covers the surface area of the villi that project into
the lumen, and lines the crypts that descend into the underlying connective tissue.
Dividing stem cells lie protected in the depth of the crypts. These stem cells generate
four types of differentiated progeny: (i) enterocytes, with densely packed microvilli
on their surfaces to increase their active area, are absorptive in function2; (ii) goblet
cells, secreting the mucin Muc28-11 and peptides such as trefoil factor 3 (Tff3)12, both
products which serve protective roles in the gut; (iii) Paneth cells, involved in the
innate defense system by secreting cryptdins, proteins of the defensin family that
kill bacteria13-15, and (iv) enteroendocrine cells, producing peptide hormones that act
on neurons and other cell types in the gut wall and regulate growth, proliferation
and digestive activities of cells of the gut and other tissues2, 6, 16. All of these cells
stem from undifferentiated multipotent stem cells located near the bottoms of the
crypts, above the Paneth cells (Fig. 1A). These multipotent stem cells cannot be
conclusively identified as they can produce all cell types within the epithelium. The
regulatory mechanism behind lineage specification has not yet been fully elucidated
as it is complex and specific markers are lacking17. The large intestine, or colon, joins
the small intestine at the ileum via a T-shaped junction
Changes in performance over time while learning to use a myoelectric prosthesis
BACKGROUND: Training increases the functional use of an upper limb prosthesis, but little is known about how people learn to use their prosthesis. The aim of this study was to describe the changes in performance with an upper limb myoelectric prosthesis during practice. The results provide a basis to develop an evidence-based training program. METHODS: Thirty-one able-bodied participants took part in an experiment as well as thirty-one age- and gender-matched controls. Participants in the experimental condition, randomly assigned to one of four groups, practiced with a myoelectric simulator for five sessions in a two-weeks period. Group 1 practiced direct grasping, Group 2 practiced indirect grasping, Group 3 practiced fixating, and Group 4 practiced a combination of all three tasks. The Southampton Hand Assessment Procedure (SHAP) was assessed in a pretest, posttest, and two retention tests. Participants in the control condition performed SHAP two times, two weeks apart with no practice in between. Compressible objects were used in the grasping tasks. Changes in end-point kinematics, joint angles, and grip force control, the latter measured by magnitude of object compression, were examined. RESULTS: The experimental groups improved more on SHAP than the control group. Interestingly, the fixation group improved comparable to the other training groups on the SHAP. Improvement in global position of the prosthesis leveled off after three practice sessions, whereas learning to control grip force required more time. The indirect grasping group had the smallest object compression in the beginning and this did not change over time, whereas the direct grasping and the combination group had a decrease in compression over time. Moreover, the indirect grasping group had the smallest grasping time that did not vary over object rigidity, while for the other two groups the grasping time decreased with an increase in object rigidity. CONCLUSIONS: A training program should spend more time on learning fine control aspects of the prosthetic hand during rehabilitation. Moreover, training should start with the indirect grasping task that has the best performance, which is probably due to the higher amount of useful information available from the sound hand
Transfer of mode switching performance:from training to upper-limb prosthesis use
BACKGROUND: Current myoelectric prostheses are multi-articulated and offer multiple modes. Switching between modes is often done through pre-defined myosignals, so-called triggers, of which the training hardly is studied. We evaluated if switching skills trained without using a prosthesis transfer to actual prosthesis use and whether the available feedback during training influences this transfer. Furthermore we examined which clinically relevant performance measures and which myosignal features were adapted during training. METHODS: Two experimental groups and one control group participated in a five day pre-test-post-test design study. Both experimental groups used their myosignals to perform a task. One group performed a serious game without seeing their myosignals, the second group was presented their myosignal on a screen. The control group played the serious game using the touchpad of the laptop. Each training session lasted 15 min. The pre- and post-test were identical for all groups and consisted of performing a task with an actual prosthesis, where switches had to be produced to change grip mode to relocate clothespins. Both clinically relevant performance measures and myosignal features were analysed. RESULTS: 10 participants trained using the serious game, 10 participants trained with the visual myosignal and 8 the control task. All participants were unimpaired. Both experimental groups showed significant transfer of skill from training to prosthesis use, the control group did not. The degree of transfer did not differ between the two training groups. Clinically relevant measure 'accuracy' and feature of the myosignals 'variation in phasing' changed during training. CONCLUSIONS: Training switching skills appeared to be successful. The skills trained in the game transferred to performance in a functional task. Learning switching skills is independent of the type of feedback used during training. Outcome measures hardly changed during training and further research is needed to explain this. It should be noted that five training sessions did not result in a level of performance needed for actual prosthesis use. Trial registration The study was approved by the local ethics committee (ECB 2014.02.28_1) and was included in the Dutch trial registry (NTR5876)
HoMEcare aRm rehabiLItatioN (MERLIN):preliminary evidence of long term effects of telerehabilitation using an unactuated training device on upper limb function after stroke
BACKGROUND: While short term effects on upper limb function of stroke patients after training with robotic devices have been studied extensively, long term effects are often not addressed. HoMEcare aRm rehabiLItatioN (MERLIN) is a combination of an unactuated training device using serious games and a telerehabilitation platform in the patient’s home situation. Short term effects showed that upper limb function improved after training with MERLIN. The aim was to determine long term effects on upper limb function and quality of life. METHODS: Six months after cessation of the 6 week MERLIN training program, the upper limb function and quality of life of 11 chronic stroke patients were assessed. Upper limb function was measured using the Wolf Motor Function Test (WMFT), Action Research Arm Test (ARAT) and Fugl-Meyer Assessment-Upper Extremity (FMA-UE). EuroQoL-5D (EQ-5D) was used to measure quality of life. RESULTS: The WMFT, ARAT and EQ-5D did not show significant differences 6 months after the training period compared to directly after training. At 6 months follow-up, FMA-UE results were significantly better than at baseline. Time plots showed a decreasing trend in all tests. CONCLUSION: Training effects were still present at 6 months follow-up, since arm function seemed similar to directly after training and FMA-UE results were better than at baseline. However, because of the decreasing trend shown in all tests, it is questionable if improvements will be maintained longer than 6 months. Due to the sample size and study design, results should be interpreted with caution. Trial registration This study is registered at the Netherlands Trial Register (NL7535). Registered 18-02-2019, https://www.trialregister.nl/trial/753
The Anatomy of Action Systems:Task Differentiation When Learning an EMG Controlled Game
This study aims to determine to what extent the task for an action system in its initial development relies on functional and anatomical components. Fifty-two able-bodied participants were randomly assigned to one of three experimental groups or to a control group. As a pre- and post-test all groups performed a computer game with the same goal and using the same musculature. One experimental group also trained to perform this test, while the other two experimental groups learned to perform a game that differed either in its goal or in the musculature used. The observed change in accuracy indicated that retaining the goal of the task or the musculature used equally increased transfer performance relative to controls. Conversely, changing either the goal or the musculature equally decreased transfer relative to training the test. These results suggest that in the initial development of an action system, the task to which the system pertains is not specified solely by either the goal of the task or the anatomical structures involved. It is suggested that functional specificity and anatomical dependence might equally be outcomes of continuously differentiating activity
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