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Many societies across the world are confronted with demographic changes, usually related to increased life expectancy and, often, relatively low birth rates. Information and communication technologies (ICT) may contribute to adequ...
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Many societies across the world are confronted with demographic changes, usually related to increased life expectancy and, often, relatively low birth rates. Information and communication technologies (ICT) may contribute to adequately support senior citizens in aging societies with respect to quality of life and quality and efficiency of health care processes. For investigating and for providing answers on whether new information and communication technologies can contribute to keeping, or even improving quality of life, health and self-sufficiency in ageing societies through new ways of living and new forms of care, the Lower Saxony Research Network Design of Environments for Ageing (GAL) had been established as a five years research project, running from 2008 to 2013. Ambient-assisted living (AAL) technologies in personal and home environments were especially important. In this article we report on the GAL project, and present some of its major outcomes after five years of research. We report on major challenges and lessons learned in running and organizing such a large, inter- and multidisciplinary project and discuss GAL in the context of related research projects. With respect to research outcomes, we have, for example, learned new knowledge about multimodal and speech-based human-machine-interaction mechanisms for persons with functional restrictions, and identified new methods and developed new algorithms for identifying activities of daily life and detecting acute events, particularly falls. A total of 79 apartments of senior citizens had been equipped with specific "GAL technology'', providing new insights into the use of sensor data for smart homes. Major challenges we had to face were to deal constructively with GAL's highly inter-and multidisciplinary aspects, with respect to research into GAL's application scenarios, shifting from theory and lab experimentation to field tests, and the complexity of organizing and, in our view, successfully managing such a large project. Overall it can be stated that, from our point of view, the GAL research network has been run successfully and has achieved its major research objectives. Since we now know much more on how and where to use AAL technologies for new environments of living and new forms of care, a future focus for research can now be outlined for systematically planned studies, scientifically exploring the benefits of AAL technologies for senior citizens, in particular with respect to quality of life and the quality and efficiency of health care.
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The paper describes a system for automatic speech recognition (ASR) that is benchmarked with data of the 3rd CHiME challenge, a dataset comprising distant microphone recordings of noisy acoustic scenes in public environments. The ...
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The paper describes a system for automatic speech recognition (ASR) that is benchmarked with data of the 3rd CHiME challenge, a dataset comprising distant microphone recordings of noisy acoustic scenes in public environments. The proposed ASR system employs various methods to increase recognition accuracy and noise robustness. Two different multi-channel speech enhancement techniques are used to eliminate interfering sounds in the audio stream. One speech enhancement method aims at separating the target speaker's voice from background sources based on non-negative matrix factorization (NMF) using variational Bayesian (VB) inference to estimate NMF parameters. The second technique is based on a time-varying minimum variance distortionless response (MVDR) beamformer that uses spatial information to suppress sound signals not arriving from a desired direction. Prior to speech enhancement, a microphone channel failure detector is applied that is based on cross-comparing channels using a modulation-spectral representation of the speech signal. ASR feature extraction employs the amplitude modulation filter bank (AMFB) that implicates prior information of speech to analyze its temporal dynamics. AMFBs outperform the commonly used frame splicing technique of filter bank features in conjunction with a deep neural network (DNN) based ASR system, which denotes an equivalent data-driven approach to extract modulation-spectral information. In addition, features are speaker adapted, a recurrent neural network (RNN) is employed for language modeling, and hypotheses of different ASR systems are combined to further enhance the recognition accuracy. The proposed ASR system achieves an absolute word error rate (WER) of 5.67% on the real evaluation test data, which is 0.16% lower compared to the best score reported within the 3rd CHiME challenge.
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In this study, we propose a novel bioresorbable bioactive implant for tibial tuberosity advancement (TTA). The implant consists of a gradually resorbing load-bearing shell which encompasses rapidly resorbing small casings loaded w...
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In this study, we propose a novel bioresorbable bioactive implant for tibial tuberosity advancement (TTA). The implant consists of a gradually resorbing load-bearing shell which encompasses rapidly resorbing small casings loaded with silica-based bioactive glass (BG) particulates which promote bone formation and reduce the risk of infection. The shell and the casings are manufactured by 3D printing from two medical grade bioresorbable polymers (a polyglycolide/lactide based and a polydioxanone based) that have different degradation rates. The casings are expected to resorb within days after surgery to expose the BG particulates while the shell would retain the load-bearing properties of the implant for the time required by bone healing. Unlike the currently used metallic devices, the novel implant is resorbed and excreted from the body once its purpose is fulfilled.
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In toy-breed dogs (bodyweight < 5 kg), the fractures of the radius and ulna are particularly common and can be caused by minimal trauma. While fracture fixation using metallic plates is a feasible treatment modality, the excessive stiffness of these devices produces the underloading of the bone which may result in the adverse bone remodelling and complications in the healing of the fracture....
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In toy-breed dogs (bodyweight < 5 kg), the fractures of the radius and ulna are particularly common and can be caused by minimal trauma. While fracture fixation using metallic plates is a feasible treatment modality, the excessive stiffness of these devices produces the underloading of the bone which may result in the adverse bone remodelling and complications in the healing of the fracture.
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Low bone quality may compromise the success of cementless total hip arthroplasty in high-risk patients such as elderly women. Zoledronic acid is a long-lasting antiresorptive agent, which is known to reduce short-term periprosthet...
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Low bone quality may compromise the success of cementless total hip arthroplasty in high-risk patients such as elderly women. Zoledronic acid is a long-lasting antiresorptive agent, which is known to reduce short-term periprosthetic bone loss. However, its effect on femoral stem stability is not well known. Forty-nine female patients with a mean age of 68 years (range, 51-85 years) scheduled to undergo cementless total hip arthroplasty due to osteoarthritis were randomized in this double-blind, placebo controlled trial to receive a single postoperative infusion of zoledronic acid or placebo. Patients were evaluated for up to four years postoperatively for femoral stem migration measured by radiostereometric analysis, bone mineral density (BMD) measured by dual X-ray absorptiometry, functional recovery, and patient-reported outcome scores. Implant survival was determined at nine years postoperatively. Zoledronic acid did not reduce the femoral stem migration that occurred predominantly during the settling period of the first 3-6 months. Subsequently, all femoral stems were radiographically osseointegrated. Zoledronic acid maintained periprosthetic BMD, while the expected loss of periprosthetic bone during the first 12 months was found in controls. Thereafter, periprosthetic BMD of Gruen zone 7 decreased even in the zoledronic acid group but remained 14.6% higher than that in the placebo group at four years postoperatively. Functional recovery was comparable across the groups. At nine years postoperatively, no revision arthroplasty had been performed. In conclusion, in women at high-risk for low BMD, zoledronic acid had a long-lasting, partially protective effect on periprosthetic bone loss, but the treatment did not enhance the initial femoral stem stability. (C) 2018 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license.
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Bio-active glass has been developed for use as a bone substitute with strong osteo-inductive capacity and the ability to form strong bonds with soft and hard tissue. The ability of this material to enhance tissue in-growth suggest...
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Bio-active glass has been developed for use as a bone substitute with strong osteo-inductive capacity and the ability to form strong bonds with soft and hard tissue. The ability of this material to enhance tissue in-growth suggests its potential use as a substitute for the dental laminate of an osteo-odonto-keratoprosthesis. A preliminary in vitro investigation of porous bio-active glass as an OOKP skirt material was carried out. Porous glass structures were manufactured from bio-active glasses 1-98 and 28-04 containing varying oxide formulation (1-98, 28-04) and particle size range (250–315 μm for 1-98 and 28-04a, 315–500 μm for 28-04b). Dissolution of the porous glass structure and its effect on pH was measured. Structural 2D and 3D analysis of porous structures were performed. Cell culture experiments were carried out to study keratocyte adhesion and the inflammatory response induced by the porous glass materials. The dissolution results suggested that the porous structure made out of 1-98 dissolves faster than the structures made from glass 28-04. pH experiments showed that the dissolution of the porous glass increased the pH of the surrounding solution. The cell culture results showed that keratocytes adhered onto the surface of each of the porous glass structures, but cell adhesion and spreading was greatest for the 98a bio-glass. Cytokine production by all porous glass samples was similar to that of the negative control indicating that the glasses do not induce a cytokine driven inflammatory response. Cell culture results support the potential use of synthetic porous bio-glass as an OOKP skirt material in terms of limited inflammatory potential and capacity to induce and support tissue ingrowth.
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The aim of this study was to characterize the microstructure and mechanical properties of porous fiber-reinforced composites (FRC). Implants made of the FRC structures are intended for cranial applications. The FRC specimens were ...
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The aim of this study was to characterize the microstructure and mechanical properties of porous fiber-reinforced composites (FRC). Implants made of the FRC structures are intended for cranial applications. The FRC specimens were prepared by impregnating E-glass fiber sheet with non-resorbable bifunctional bis-phenyl glycidyl dimethacrylate and triethylene glycol dimethacrylate resin matrix. Four groups of porous FRC specimens were prepared with a different amount of resin matrix. Control group contained specimens of fibers, which were bound together with sizing only. Microstructure of the specimens was analyzed using a micro computed tomography (micro-CT) based method. Mechanical properties of the specimens were measured with a tensile test. The amount of resin matrix in the specimens had an effect on the microstructure. Total porosity was 59.5 % (median) in the group with the lowest resin content and 11.2 % (median) in the group with the highest resin content. In control group, total porosity was 94.2 % (median). Correlations with resin content were obtained for all micro-CT based parameters except TbPf. The tensile strength of the composites was 21.3 MPa (median) in the group with the highest resin content and 43.4 MPa (median) in the group with the highest resin content. The tensile strength in control group was 18.9 MPa (median). There were strong correlations between the tensile strength of the specimens and most of the micro-CT based parameters. This experiment suggests that porous FRC structures may have the potential for use in implants for cranial bone reconstructions, provided further relevant in vitro and in vivo tests are performed.
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Biostable fiber-reinforced composite (FRC) implants prepared from bisphenol-A-dimethacrylate and triethyleneglycoldimethacrylate resin reinforced with E-glass fibers have been successfully used in cranial reconstructions in 15 pat...
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Biostable fiber-reinforced composite (FRC) implants prepared from bisphenol-A-dimethacrylate and triethyleneglycoldimethacrylate resin reinforced with E-glass fibers have been successfully used in cranial reconstructions in 15 patients. Recently, porous FRC structures were suggested as potential implant materials. Compared with smooth surface, porous surface allows implant incorporation via bone ingrowth, but is also a subject to bacterial attachment. Non-cytotoxic silver–polysaccharide nanocomposite coatings may provide a way to decrease the risk of bacterial contamination of porous FRC structures. This study is focused on the in vitro characterization of the effect porosity on the antimicrobial efficiency of the coatings against Staphylococcus aureus and Pseudomonas aeruginosa by a series of microbiological tests (initial adhesion, antimicrobial efficacy, and biofilm formation). Characterization included confocal laser scanning microscopy and scanning electron microscopy. The effect of porosity on the initial attachment of S. aureus was pronounced, but in the case of P. aeruginosa the effect was negligible. There were no significant effects of the coatings on the initial bacterial attachment. In the antimicrobial efficacy test, the coatings were potent against both strains regardless of the sample morphology. In the biofilm tests, there were no clear effects either of morphology or of the coating. Further coating development is foreseen to achieve a longer-term antimicrobial effect to inhibiting bacterial implant colonization.
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Medical polymers of biostable nature (e.g. polymethylmetacrylate, PMMA) are widely used in various clinical applications. In this study, novel PMMA-based composite bone cement was prepared. Bioactive glass (BAG) particulate filler...
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Medical polymers of biostable nature (e.g. polymethylmetacrylate, PMMA) are widely used in various clinical applications. In this study, novel PMMA-based composite bone cement was prepared. Bioactive glass (BAG) particulate filler (30 wt%) was added to enhance potentially the integration of bone to the cement. The polymer matrix was functionalized with trimethoxysilyl to achieve an interfacial bond between the matrix and the fillers of BAG. The amount of trimethoxysilyl in the monomer system varied from 0 to 75 wt%. The effects of dry and wet (simulated body fluid, SBF at +37 degrees C for 5 weeks) conditions were investigated. In total, 20 groups of specimens were prepared. The specimens were subjected to a destructive mechanical test in compression. Scanning electron microscopy (SEM) and micro-computed tomography (micro-CT) were used to study the surface and the three-dimensional morphology of the specimens. The results of the study indicated that the addition of trimethoxysilyl groups led to the formation of a hybrid polymer matrix which, in lower amounts (<10 wt% of total weight), did not significantly affect the compression properties. However, when the specimens stored in dry and wet conditions were compared, the water sorption increased the compression strength (similar to 5-10 MPa per test group). At the same time, the water sorption also caused an evident porous structure formation for the specimens containing BAG and siloxane formation in the hybrid polymer matrix. (C) 2015 Elsevier Ltd. All rights reserved.
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Background and purpose - Selective androgen receptor modulators (SARMs) have been developed to have systemic anabolic effects on bones and muscles without the adverse effects of steroidal androgens. One unexplored therapeutic opti...
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Background and purpose - Selective androgen receptor modulators (SARMs) have been developed to have systemic anabolic effects on bones and muscles without the adverse effects of steroidal androgens. One unexplored therapeutic option is the targeted application of SARMs for the enhancement of local new bone formation. We evaluated the osteogenic efficacy of a locally released SARM (ORM-11984).
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