526 research outputs found
Design Principles For Knowledge Productivity
This study explores the learning processes that contribute to knowledge productivity: the improvement and innovation of an organisationās procedures, products and services, based on the development and application of new knowledge. Based on reconstruction and parallel case studies in more than 20 innovation practices, we formulated eleven design principles. Those principles help key players to turn the work environment into a learning environment that supports knowledge productivity
Relating learning, knowledge creation and innovation: Case studies into knowledge productivity
This study explores which learning processes contribute to the improvement and innovation of an organisationās procedures, products and services. It aims to find the variables that promote or inhibit these learning processes. For this purpose a conceptual framework was developed. This framework helps both to better understand learning processes that lead to improvement and innovation and to stimulate knowledge productivity in practice. In this article, we first present the conceptual framework. Next, we present the results of 16 reconstruction studies deployed in various organisations in the Netherlands, China and Indonesia. The results confirm that the elements in our framework play an important role in developing and using new knowledge that is needed for improvement and innovation. An earlier version of this article was as a paper presented at the fifth European conference on Organisational Knowledge, Learning and Capabilities
āThat They Point Is All There Is to Itā: Wittgensteinās Romanticist Aesthetics
Why is aesthetics important to Wittgenstein? What, according to him, is the function of the aesthetic? My answer consists of three parts: first, I argue that Wittgenstein finds himself in an aporia of normative consciousness ā that is to say, a problem with regard to our awareness of the world in terms of its relation to a norm. Second, I argue that the function of Wittgensteinās aesthetic writings is to deal with this aporia. Third, through a comparison with Friedrich Schlegelās writings on allegory, I try to show that the way in which Wittgenstein resolves the aporia renders him a Romanticist philosopher. The point of an aesthetic interaction, for Wittgenstein, is that it can render clear what cannot be described without running against the walls of our cage: the absolute. Through aesthetic interactions we are able to (indirectly) access a ground for norms by which we experience ourselves as unconditionally bound
A Comparative Finite-Element Analysis of Bone Failure and Load Transfer of Osseointegrated Prostheses Fixations
An alternative solution to conventional stumpāsocket prosthetic limb attachment is offered by direct skeletal fixation. This study aimed to assess two percutaneous trans-femoral implants, the OPRA system (Integrum AB, Gƶteborg, Sweden), and the ISP Endo/Exo prosthesis (ESKA Implants AG, LĆ¼beck, Germany) on bone failure and stemābone interface mechanics both early post-operative (before bony ingrowth) and after full bone ingrowth. Moreover, mechanical consequences of implantation of those implants in terms of changed loading pattern within the bone and potential consequences on long-term bone remodeling were studied using finite-element models that represent the intact femur and implants fitted in amputated femora. Two experimentally measured loads from the normal walking cycle were applied. The analyses revealed that implantation of percutaneous prostheses had considerable effects on stress and strain energy density levels in bone. This was not only caused by the implant itself, but also by changed loading conditions in the amputated leg. The ISP design promoted slightly more physiological strain energy distribution (favoring long-term bone maintenance), but the OPRA design generated lower bone stresses (reducing bone fracture risk). The safety factor against mechanical failure of the two percutaneous designs was relatively low, which could be improved by design optimization of the implants
Intraoral ultrasonographic features of tongue cancer and the incidence of cervical lymph node metastasis
Purpose: The purpose of this study was to investigate the relationship between the visual characteristics of tongue lesion images obtained through intraoral ultrasonographic examination and the occurrence of late cervical lymph node metastasis in patients with tongue cancer. Patients and Methods: This study investigated patients with primary tongue cancer who were examined using intraoral ultrasonography at Hiroshima University Hospital between January 2014 and December 2017. The inclusion criteria were squamous cell carcinoma, curative treatment administration, lateral side of tongue, surgery or brachytherapy alone, no cervical lymph node or distant metastasis as primary treatment, and treatment in our hospital. The exclusion criteria were carcinoma in situ, palliative treatment, dorsum of tongue, and multiple primary cancers. The follow-up period was more than 1 year. The primary endpoint was the occurrence of late cervical lymph node metastasis, and the primary predictor variables were age, gender, longest diameter, thickness, margin or border shapes of the lesion, and treatment methods. The relationship between the occurrence of late cervical lymph node metastasis and the longest diameter, thickness, margin types, and border types as evaluated through intraoral ultrasonography were assessed. The data were collected through a retrospective chart review. Results: Fifty-four patients were included in this study. The analysis indicated that irregular lesion margins were significantly associated with the occurrence of late cervical lymph node metastasis (P < .0001). The cutoff value for late cervical lymph node metastasis was 21.2 mm for the longest diameter and 3.9 mm for the thickness. Conclusions: The results of this study indicates that the irregular lesion margin assessed using intraoral ultrasonography may serve as an effective predictor of late cervical lymph node metastasis in N0 cases. (C) 2020 American Association of Oral and Maxillofacial Surgeon
WISER Deliverable D3.3-2: The importance of invertebrate spatial and temporal variation for ecological status classification for European lakes
European lakes are affected by many human induced disturbances. In principle, ecological
theories predict that the structure and functioning of benthic invertebrate assemblage (one of
the Biological Quality Elements following the Water Framework Directive, WFD
terminology) change in response to the level of disturbances, making this biological element
suitable for assessing the status and management of lake ecosystems. In practice, to set up
assessment systems based on invertebrates, we need to distiguish community changes that are
related to human pressures from those that are inherent natural variability. This task is
complicated by the fact that invertebrate communities inhabiting the littoral and the profundal
zones of lakes are constrained by different factors and respond unevenly to distinct human
disturbances. For example it is not clear yet how the invertebrates assemblages respond to
watershed and shoreline alterations, nor the relative importance of spatial and temporal
factors on assemblage dynamics and relative bioindicator values of taxa, the habitat
constraints on species traits and other taxonomic and methodological limitations.
The current lack of knowledge of basic features of invertebrate temporal and spatial variations
is limiting the fulfillment of the EU-wide intercalibration of lake ecological quality
assessment systems in Europe, and thus compromising the basis for setting the environmental
objectives as required by the WFD. The aim of this deliverable is to provide a contribution
towards the understanding of basic sources of spatial and temporal variation of lake
invertebrate assemblages. The report is structured around selected case studies, manly
involving the analysis of existing datasets collated within WISER. The case studies come
from different European lake types in the Northern, Central, Alpine and Mediterranean
regions. All chapters have an obvious applied objective and our aim is to provide to those
dealing with WFD implementation at various levels useful information to consider when
designing monitoring programs and / or invertebrate-based classification systems
Evaluation of laxity tests with a musculoskeletal model of total knee arthroplasty
Introduction Musculoskeletal models are emerging as potential tools for the use in many clinical applications. One important example is aid to the clinical decision in the orthopaedic field. Recently, a patient-specific model of Cruciate-Retaining Total Knee Arthroplasty (CR-TKA) was presented and validated with respect to knee joint forces and kinematics [1]. However, the ligament restraints were not calibrated and inaccuracies in knee kinematic predictions were present. The objective of this study was to evaluate the effect of ligament calibration on the performance of simulated laxity tests. Methods A musculoskeletal model of CR-TKA was previously described [1]. The model comprised the musculoskeletal architecture of a TKA patient and a force-dependent model of the prosthetic knee and patellofemoral joint. Ligament restraints were modelled using non-linear springs and contact was solved using a rigid formulation. To calibrate the ligament parameters we simulated anterior/posterior, valgus/varus and endo-/exorotation laxity tests. Each test was performed at four different knee flexion angles (0, 30, 60, 90 deg). The anterior (respectively posterior) laxity load consisted of a 35 N force applied on the tibia at a distance of approximately 15 cm from the surface of the tibial component, pointing anteriorly (respectively posteriorly). Valgus (respectively varus) test was simulated by applying a force on the tibia at a distance of approximately 15 cm from the ankle joint, pointing laterally (respectively medially) so that the resulting moment was equal to 10 Nm. For the endo- (respectively exo-) rotation a 1.5 Nm torque was applied to the longitudinal axis of the tibia. Laxity envelopes for each test were calculated as the difference between the values obtained in the two opposite directions of the test. Manual changes to ligament insertion site, stiffness, and reference strain were made iteratively in order to obtain laxity envelopes close to those reported in the literature for cadaveric tests on a CR-TKA [2]. All the laxity tests were eventually simulated with the same ligament configuration. Results The results for all simulated laxity tests and the reference values from the literature are summarized in Table 1. 0Ā° 30Ā° 60Ā° 90Ā° AP (M) 3.5mm 4.2mm 1.0mm 1.0mm AP (L) 1.5mm 5mm 4mm 4.5mm VV (M) 0.9Ā° 4.3Ā° 2.6Ā° 1.5Ā° VV (L) 3.0Ā° 6.0Ā° 7.0Ā° 7.0Ā° EE (M) 7.0Ā° 16.5Ā° 4.0Ā° 5.5Ā° EE (L) 6.5Ā° 22.0Ā° 21.0Ā° 23.0Ā° Table 1: AP: Anterior/Posterior, VV: Valgus/Varus, EE: Endo-/Exorotation, M: Model prediction, L: Literature value Discussion The laxity envelopes predicted by the model were in partial agreement with those reported in the literature. The largest differences were noted for 60-90 degrees of knee flexion for all laxity tests, where the model showed considerably less laxity. These deviations may be attributable to actual differences between the implant design and subject geometry currently simulated and those used in the cadaveric tests. In future studies we aim to simulate surgical variations such as implant size and positioning, joint line elevation and ligament restraint. This musculoskeletal model of TKA has potential as a pre-operative planning tool for orthopaedic interventions. References Marra et al, J Biomech Eng, 137, 2015 Saeki et al, Clin Orthop Relat Res, 392:184-189, 200
Do various imaging modalities provide potential early detection and diagnosis of medication-related osteonecrosis of the jaw? A review
Objective: Patients with medication-related osteonecrosis of the jaw (MRONJ) often visit their dentists at advanced stages and subsequently require treatments that greatly affect quality of life. Currently, no clear diagnostic criteria exist to assess MRONJ, and the definitive diagnosis solely relies on clinical bone exposure. This ambiguity leads to a diagnostic delay, complications, and unnecessary burden. This article aims to identify imaging modalities' usage and findings of MRONJ to provide possible approaches for early detection. Methods: Literature searches were conducted using PubMed, Web of Science, Scopus, and Cochrane Library to review all diagnostic imaging modalities for MRONJ. Results: Panoramic radiography offers a fundamental understanding of the lesions. Imaging findings were comparable between non-exposed and exposed MRONJ, showing osteolysis, osteosclerosis, and thickened lamina dura. Mandibular cortex index Class II could be a potential early MRONJ indicator. While three-dimensional modalities, CT and CBCT, were able to show more features unique to MRONJ such as a solid type periosteal reaction, buccal predominance of cortical perforation, and bone-within-bone appearance. MRI signal intensities of vital bones are hypointense on T1WI and hyperintense on T2WI and STIR when necrotic bone shows hypointensity on all T1WI, T2WI, and STIR. Functional imaging is the most sensitive method but is usually performed in metastasis detection rather than being a diagnostic tool for early MRONJ. Conclusion: Currently, MRONJ-specific imaging features cannot be firmly established. However, the current data are valuable as it may lead to a more efficient diagnostic procedure along with a more suitable selection of imaging modalities
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