The long-term mechanical integrity of non-reinforced PEEK-OPTIMA polymer for demanding spinal applications: experimental and finite-element analysis

Polyetheretherketone (PEEK) is a novel polymer with potential advantages for its use in demanding orthopaedic applications (e.g. intervertebral cages). However, the influence of a physiological environment on the mechanical stability of PEEK has not been reported. Furthermore, the suitability of the polymer for use in highly stressed spinal implants such as intervertebral cages has not been investigated. Therefore, a combined experimental and analytical study was performed to address these open questions. A quasi-static mechanical compression test was performed to compare the initial mechanical properties of PEEK-OPTIMA polymer in a dry, room-temperature and in an aqueous, 37°C environment (n=10 per group). The creep behaviour of cylindrical PEEK polymer specimens (n=6) was measured in a simulated physiological environment at an applied stress level of 10MPa for a loading duration of 2000hours (12weeks). To compare the biomechanical performance of different intervertebral cage types made from PEEK and titanium under complex loading conditions, a three-dimensional finite element model of a functional spinal unit was created. The elastic modulus of PEEK polymer specimens in a physiological environment was 1.8% lower than that of specimens tested at dry, room temperature conditions (P<0.001). The results from the creep test showed an average creep strain of less than 0.1% after 2000hours of loading. The finite element analysis demonstrated high strain and stress concentrations at the bone/implant interface, emphasizing the importance of cage geometry for load distribution. The stress and strain maxima in the implants were well below the material strength limits of PEEK. In summary, the experimental results verified the mechanical stability of the PEEK-OPTIMA polymer in a simulated physiological environment, and over extended loading periods. Finite element analysis supported the use of PEEK-OPTIMA for load-bearing intervertebral implant

Linguiste ou non-linguiste ? Réflexions sur une dichotomie controversée à partir de l’analyse de métadiscours sur les langues régionales

Plusieurs termes existent pour distinguer l’expert du non-expert et le linguiste du non-linguiste. Cette bipartition, à première vue plausible, pose des problèmes quand on l’applique à une situation communicative concrète. S’agit-il d’une dichotomie rigide ? Ou d’une distinction à critères variables, voire d’une construction discursive ? Est-elle valable pour tout genre de métadiscours ? Pour répondre à ces questions, nous discuterons brièvement les désignations coexistantes pour se référer au linguiste et au non-linguiste ainsi que les critères auxquels elles renvoient. L’analyse des métadiscours sur les langues régionales en France nous permettra d’examiner la dépendance de ces critères vis-à-vis du type de métadiscours et de la situation communicative.Several terms serve to distinguish between an expert and a non-expert. This division, though at first sight plausible, causes problems as soon as it is applied to an actual communication situation. Are we dealing with a rigid dichotomy? Or a distinction based on variable criteria ? Or even a discursive construction? Is it valid for all kinds of metadiscourses? To answer these questions, we will briefly discuss the terms that coexist to refer to a linguist and a non-linguist, as well as the criteria according to which the division is made. As an example, we will analyse metadiscourses about regional languages in France. This will allow us to examine to which extent such criteria depend on the kind of metadiscourse or on the communicative situation

The prevalence and incidence of musculoskeletal symptoms among hospital physicians: a systematic review

Physicians are exposed to a range of work-related risk factors that may result in occupational diseases. This systematic review aims at shedding light on the prevalence and incidence of musculoskeletal complaints among hospital physicians. A systematic literature search was performed in Pubmed and EMBASE (1990-2010), and methodological quality criteria were applied. A search was done for musculoskeletal complaints. Five medium-quality studies and three high-quality studies were included in this review. The definitions and assessment used in the studies for musculoskeletal complaints were different. In short, the frequently reported prevalence for hand and wrist pain was 8-33 and 0%, 17% for shoulder pain, and 9-28% for neck pain. Moreover, the annual prevalence of low back pain was between 33 and 68%. The limited number of studies makes it difficult to draw conclusions, and the results should be intepreted with care. In conclusion, musculoskeletal complaints may be work-related complaints in hospital physicians, which need future attentio

IL POTENZIALE DELL’ITALIANO COME LINGUA PONTE: RISULTATI DI UNO STUDIO BASATO SU INTERVISTE CON (FUTURI) INSEGNANTI D’ITALIANO

A causa dell’abituale sequenza linguistica nel sistema scolastico tedesco, l’italiano come “lingua ponte” viene difficilmente preso in considerazione. Tuttavia, tra gli apprendenti e tra gli (futuri) insegnanti esistono persone con un contesto migratorio italiano. Perciò, una didattica del plurilinguismo potrebbe rispettare il potenziale di questa lingua di origine come lingua ponte. L’articolo intende discutere se l’italiano presenti questo potenziale o no, tenendo particolarmente conto della visione soggettiva di insegnanti e apprendenti. Si basa su interviste svolte presso l’università della Ruhr a Bochum con 31 (futuri) insegnanti d’italiano. L’obiettivo è valutare il potenziale dell’italiano come lingua ponte alla luce delle interviste. Verranno anche discussi approcci ad una didattica del plurilinguismo che tengono anche conto delle strategie di apprendimento e delle esperienze linguistiche personali. &nbsp; The potential of Italian as a bridge language: results of a study based on interviews with (future) Italian teachers Due to the language sequence in the German education system, models of multilingual teaching tend to ignore Italian as a bridge language. However, among students and (future) teachers, there are people with an Italian migration background. Therefore, multilingual teaching could take the potential of this heritage language as a bridge language into account. The article discusses this potential with a special focus on the subjective views of teachers and students, based on interviews carried out at the University of Bochum with 31 (future) teachers of Italian. The interviews were analyzed with regard to the potential of Italian as a bridge language. Furthermore, multilingual teaching approaches that also take learning strategies and linguistic attitudes into account will be discussed

The role of food parcel use on dietary intake: perception of Dutch food bank recipients:a focus group study

OBJECTIVE: To gain insight in Dutch food bank recipients' perception on the content of the food parcels, their dietary intake and how the parcels contribute to their overall dietary intake. DESIGN: Eleven semi-structured focus group discussions were conducted. Focus group topics were based on Andersons food insecurity definition: the lack of availability of nutritionally adequate foods and the assured ability to acquire foods in socially acceptable ways. Data were coded and analysed with Atlas.ti 7.0 software, using the framework approach. SETTING: Seven food banks throughout the Netherlands. PARTICIPANTS: A total of 44 Dutch food bank recipients. RESULTS: Food bank recipients were not always satisfied with the amount, quality, variation and type of foods in the food parcel. For the participants who could afford to, supplementing the food parcel was reported as main reason for buying foods, and price was the most important aspect in selecting these foods. Participants were not satisfied with their dietary intake; they mainly reported not having enough to eat. The content of the food parcel importantly influenced participants' overall dietary intake. Finally, participants reported struggling with their feelings of dissatisfaction, while also being grateful for the foods they receive. CONCLUSIONS: This study suggests that, despite their best efforts, food banks are not meeting food bank recipients' needs. Our results provide valuable directions for improving the content of the food parcels by increasing the quantity, quality and variation in the foods supplied. Whether this also improves the dietary intake of recipients needs to be determined

Anatomical parameters for musculoskeletal modeling of the hand and wrist

International audienceA musculoskeletal model of the hand and wrist can provide valuable biomechanical and neurophysiological insights, relevant for clinicians and ergonomists. Currently, no consistent data-set exists comprising the full anatomy of these upper extremity parts. The aim of this study was to collect a complete anatomical data-set of the hand and wrist, including the intrinsic and extrinsic muscles. One right lower arm, taken from a fresh frozen female specimen, was studied. Geometrical data for muscles and joints were digitized using a 3D optical tracking system. For each muscle, optimal fiber length and physiological cross-sectional area were assessed based on muscle belly mass, fiber length, and sarcomere length. A brief description of model, in which these data were imported as input, is also provided. Anatomical data including muscle morphology and joint axes (48 muscles and 24 joints) and mechanical representations of the hand are presented. After incorporating anatomical data in the presented model, a good consistency was found between outcomes of the model and the previous experimental studies

Potential biomarkers for diagnosis of sarcoidosis using proteomics in serum

SummaryBackgroundSarcoidosis is a multi-systemic inflammatory disorder, which affects the lungs in 90% of the cases. The main pathologic feature is chronic inflammation resulting in non-caseating granuloma formation. Until now there is no satisfying biomarker for diagnosis or prognosis of sarcoidosis. This study is focused on the detection of potential biomarkers in serum for the diagnosis of sarcoidosis using surface-enhanced laser desorption ionization-time of flight-mass spectrometry (SELDI-TOF-MS).MethodsFor detection of potential biomarkers, protein profiles of anion exchange fractionated serum of 35 sarcoidosis patients and 35 healthy controls were compared using SELDI-TOF-MS. Sensitivities and specificities of the potential biomarkers obtained with SELDI-TOF-MS, generated with decision tree algorithm, were compared to the conventional markers angiotensin converting enzyme (ACE) and soluble interleukin-2 receptor (sIL-2R).ResultsOptimal classification was achieved with metal affinity binding arrays. A single marker with a mass-to-charge (m/z) value of 11,955 resulted in a sensitivity and specificity of 86% and 63%, respectively. A multimarker approach of two peaks, m/z values of 11,734 and 17,377, resulted in a sensitivity and specificity of 74% and 71%, respectively. These sensitivities and specificities were higher compared to measurements of ACE and sIL-2R. Identification of the peak at m/z 17,377 resulted in the α-2chain of haptoglobin.ConclusionsThis study acts as a proof-of-principle for the use of SELDI-TOF-MS in the detection of new biomarkers for sarcoidosis. The peak of the multimarker at m/z 17,377 was identified as the α-2chain of haptoglobin

Development and implementation of a lifestyle intervention to promote physical activity and healthy diet in the Dutch general practice setting: the BeweegKuur programme

<p>Abstract</p> <p>Background</p> <p>The number of patients with diabetes is increasing. BeweegKuur (Dutch for 'Exercise Therapy') is a Dutch lifestyle intervention which aims to effectively and feasibly promote physical activity and better dietary behaviour in primary health care to prevent diabetes.</p> <p>Methods</p> <p>The goal of this paper is to present the development process and the contents of the intervention, using a model of systematic health promotion planning. The intervention consists of a 1-year programme for diabetic and prediabetic patients. Patients are referred by their general practitioner (GP) to a lifestyle advisor (LSA), usually the practice nurse or a physiotherapist. Based on specific inclusion criteria and in close collaboration with the patient, an individual exercise programme is designed and supervised by the LSA. This programme can be attended at existing local exercise facilities or (temporarily) under the supervision of a specialized exercise coach or physiotherapist. All participants are also referred to a dietician and receive diet-related group education. In the first pilot year (2008), the BeweegKuur programme was implemented in 7 regions in the Netherlands (19 GP practices and health centres), while 14 regions (41 GP practices and health centres) participated during the second year. The aim is to implement BeweegKuur in all regions of the Netherlands by 2012.</p> <p>Discussion</p> <p>The BeweegKuur programme was systematically developed in an evidence- and practice-based process. Formative monitoring studies and (controlled) effectiveness studies are needed to examine the diffusion process and the effectiveness and cost-effectiveness of the intervention.</p

Optimal stimulation settings for CMAP scan registrations

Background: The CMAP (Compound Muscle Action Potential) scan is a non-invasive electrodiagnostic tool, which provides a quick and visual assessment of motor unit potentials as electrophysiological components that together constitute the CMAP. The CMAP scan records the electrical activity of the muscle (CMAP) in response to transcutaneous stimulation of the motor nerve with gradual changes in stimulus intensity. Large MUs, including those that result from collateral reinnervation, appear in the CMAP scan as so-called steps, i.e., clearly visible jumps in CMAP amplitude. The CMAP scan also provides information on nerve excitability. This study aims to evaluate the influence of the stimulation protocol used on the CMAP scan and its quantification. Methods: The stimulus frequency (1, 2 and 3 Hz), duration (0.05, 0.1 and 0.3 ms), or number (300, 500 and 1000 stimuli) in CMAP scans of 23 subjects was systematically varied while the other two parameters were kept constant. Pain was measured by means of a visual analogue scale (VAS). Non-parametric paired tests were used to assess significant differences in excitability and step variables and VAS scores between the different stimulus parameter settings. Results: We found no effect of stimulus frequency on CMAP scan variables or VAS scores. Stimulus duration affected excitability variables significantly, with higher stimulus intensity values for shorter stimulus durations. Step variables showed a clear trend towards increasing values with decreasing stimulus number. Conclusions: A protocol delivering 500 stimuli at a frequency of 2 Hz with a 0.1 ms pulse duration optimized CMAP scan quantification with a minimum of subject discomfort, artefact and duration of the recording. CMAP scan variables were influenced by stimulus duration and number; hence, these need to be standardized in future studies