Gino Verleye

Odds, prevalence and predictors of sleep problems in school-age normal children.

The objectives of the study were to describe the prevalence, odds, and predictors of 36 paediatric sleep behaviours and describe their coexistence in a school‐age normal population. The design was community‐based questionnaire survey of sleep–wake patterns, sleep environment, and 36 sleep behaviours indicative of six sleep disorder‐subscales using the Health‐Behaviour Questionnaire. A caregivers’ report of 3045 children aged 6–13 years in Belgium constituted the participants. Prevalence of each sleep behaviour was calculated. Log‐linear modelling within and between the sleep disorder‐subscales was used to screen for coexistence. The effect size of selected night‐time parameters to the likelihood of sleep behaviours and disorder‐subscale was expressed as odds ratios via logit regression analysis. Significant differences in sleep–wake patterns were found between weekday and weekend. Ranking by odds showed that: (1) sleep problems such as ‘tired when waking up’, ’repetitive limb movements’, ‘going to bed reluctantly’, and ‘sleep paralysis’ and; (2) the disorder‐subscale ‘excessive somnolence’ are common in children. Coexistences within and between disorder‐subscales of sleep problems are evident in a school‐age, normal population. These results suggest that disorders of excessive somnolence (DES) are highly prevalent in a non‐clinical sample of school‐age children. Furthermore, sleep‐onset latency and a noisy, not well‐darkened room are predictive towards the odds for exhibiting sleep problems and disorders. It is advocated that more information on the importance of good sleep–wake hygiene should reach parents and children.

Proposed framework for evaluating quality of experience in a mobile, testbed-oriented living lab setting

The framework presented in this paper enables the evaluation of Quality of Experience (QoE) in a mobile, testbed-oriented Living Lab setting. As a result, it fits within the shift towards more user-centric approaches in innovation research and aims to bridge the gap between technical parameters and human experience factors. In view of this, Quality of Experience is seen as a multi-dimensional concept, which should be considered from an interdisciplinary perspective. Although several approaches for evaluating perceived QoE have been proposed in the past, they tend to focus on a limited number of objective dimensions and fail to grasp the subjective counterparts of users’ experiences. We therefore propose a distributed architecture for monitoring network Quality of Service (QoS), context information and subjective user experience based on the functional requirements related to real-time experience measurements in real-life settings. This approach allows us to evaluate all relevant QoE-dimensions in a mobile context.

Forecasting broadband Internet adoption on trains in Belgium

Thanks to the massive success of mobile access devices such as netbooks or Apples iPhone 3G, Internet on the move has become one of the prominent features of todays information society. With the emergence of wireless and mobile communication networks, the railroad industry is now catching up on this new technology in their battle with low-cost operators to bring more productivity and entertainment possibilities to its passengers. With millions of daily commuters as potential service users, this transport branch offers high business opportunities. However, while most field trials and research effort have mainly focused on the enabling technology, little research effort has been conducted to forecast the demand-side. This article tries to fill this gap by presenting original results gathered from a large-scale survey amongst 1324 regular train travellers. By means of the Product Specific Adoption Potential method, we predict the potential market penetration of wireless Internet services onboard trains and estimate the size and nature of five adopter segments in terms of socio-demographics, drivers and thresholds, willingness to pay, applications and quality of service. We will discuss the practical implications of these insights in order to develop viable business models, set up introduction strategies and build out user-driven infrastructure networks.

Differentiation Between Dementia and Depression Among Older Persons: Can the Difference Between Actual and Premorbid Intelligence Be Useful?

We wanted to investigate whether the difference between actual and premorbid intelligence can be useful to make an early differentiation between Alzheimers disease (AD) and depression among elderly. A Dutch version of the National Adult Reading Test (NLV), a measure of premorbid IQ and the Raven Coloured Progressive Matrices (RCPM), a measure of actual intelligence were administered to patients with mild (34) and moderate (27) AD, depressed elderly (36) and healthy control subjects (51). Logistic regression analyses revealed that intellectual decline (i.e. subtracting NLV percentile score from RCPM percentile score) was only able to predict group membership when moderate AD patients were compared to depressed and healthy individuals. Our results indicate that intellectual decline may not be a concomitant of elderly depression. However, the differentiation between mild AD and elderly depression can not be made by means of the difference between premorbid (NLV) and actual (RCPM) intelligence scores.

The Effectiveness of Green Advertisements: Combining Ad-based and Consumer-based Research

In the late 60s and early 70s, people started to worry about the deteriorating effects their consumption behavior may have on the environment. Accordingly, consumers were searching for alternative ways to decrease their ecological footprint (Montoro-Rios, Luque-Martinez, Fuentes-Moreno & Canadas-Soriano, 2006), and they incited companies to take care of the environment in their organizational processes (Ottman, 1993).

ISQ calculation evaluation of in vitro laser scanning vibrometry-captured resonance frequency

BackgroundImplant stability testing at various stages of implant therapy by means of resonance frequency analysis is extensively used. The overall measurement outcome is a function of the resulting stiffness of three entities: surrounding bone, bone-implant complex, and implant-Smartpeg complex. The influence of the latter on the overall measurement results is presently unknown. It can be investigated in vitro by use of imbedded implants with mounted Smartpegs. This enables to keep the influence of the two other entities constant and controlled.The purpose of this study is to verify if a laboratory laser Doppler vibrometry technology-based procedure results in comparable ISQ results after calculation of captured resonance frequency spectra by aid of the Osstell algorithm with direct Osstell IDX device measurements.MethodsA laboratory procedure was engineered to record frequency spectra of resin-imbedded test implants with mounted Smartpegs, after electromagnetic excitation with the Osstell IDX device and laser Doppler vibrometry response detection. Fast Fourier transformation data processing of resonance frequency data resulted in determination of a maximum resonance frequency values allowing calculation of implant stability quotient (ISQ) values using the Osstell algorithm.ResultsLaboratory-based ISQ values were compared to Osstell IDx device-generated ISQ values for Straumann tissue level, Ankylos, and 3i Certain implant systems. For both systems, a correlation coefficient r = 0.99 was found. Furthermore, a clinically rejectable mean difference of 0.09 ISQ units was noted between both datasets.ConclusionsThe proposed laboratory method with the application of the Osstell algorithm for ISQ calculation is appropriate for future studies to in vitro research aspects of resonance frequency analysis implant stability measurements.

Validation of topographic hybrid single-photon emission computerized tomography with computerized tomography scan in patients with and without nonspecific chronic low back pain : a prospective comparative study

BACKGROUND CONTEXT The evidence for the treatment for nonspecific chronic low back pain (ns CLBP) is very weak. Besides the complexity of the pain experience, a good biological marker or tool enabling identification of a pain generator is lacking. Hybrid imaging, combining single-photon emission computerized tomography (SPECT) with computerized tomography (CT) scan, has been proposed as useful in the diagnostic workup of patients with CLBP. PURPOSE To evaluate the sensitivity of SPECT-CT in patients with ns CLBP (Group I) as compared with patients without CLBP (Group II). STUDY DESIGN A prospective comparative study. PATIENT SAMPLE Two hundred patients were enrolled: 96 in Group I and 104 in Group II. OUTCOME MEASURES Only the physiological measurement of the incidence of hot spots was performed. The hot spots were rated as follows: 0=normal; 1=slightly colored (no hot spot on whole-body bone scan); and 2=clear hot spot (can be identified on the whole-body bone scan and confirmed on SPECT). To analyze the interobserver agreement when using this scoring system, a second independent reading was performed for 50 randomly chosen records. METHODS Two hundred patients divided into two groups were referred to the department of Medical and Molecular Imaging for a topographic SPECT-CT. The first group consisted of patients with ns CLBP, diagnosed by a neurosurgeon. The control group consisted of patients referred for SPECT-CT for non-spinal conditions. Hot spots were assessed for all patients. A second independent reading, blinded for the results of the first reader, was performed on 25 randomly selected patients in each group. This study was investigator initiated, and no funding was received. None of the authors or their proxies have a potential conflict of interest. RESULTS The odds of finding a normal image in the control group are 2.05 times higher than in Group I. The sensitivity score equals 2.37, meaning that the probability of detecting a hot spot (levels 1 or 2) is more than two times higher in Group I. When focusing on level 2 hot spots only, this score rises to 7.02, indicative of a high sensitivity. CONCLUSIONS Single-photon emission computerized tomography with computerized tomography might have potential in the diagnostic workup of patients with ns CLBP, owing to its higher sensitivity when compared with other advanced medical imaging modalities.

Secondary implant stability outcome of immediate versus late placed variable-thread implants in the maxilla. A retrospective cohort study

Background The healing of xenograft augmentated intra-alveolar gaps following immediate implant placement (IMIP) after tooth extraction is likely to differ in time and density compared to the native bone part that directly contacts the implant. Material and Methods Secondary implant stability (SIS) data recorded 2-3 months following a late implant placement protocol (LIP) (n= 43) and 6-8 months following an immediate implant placement protocol (IMIP) (n=33) of variable-thread implants (Nobel Active™) in the maxilla were retrospectively collected from files of 63 patients (42 females, 21 males). Statistical analysis was performed using a generalized estimating equation model (GEE). Data split-up according to implant diameter (RP, Ø= 4.3mm) , narrow platform (NP, Ø= 3.5mm) was adopted. Results For NP implants, the mean ISQ (±SD) values were 70.84 (±4.86) in LIP group and 72.41 (±3.89) in the IMIP group. For RP implants, mean ISQ (±SD) values were 73.45 (±8.77) in the LIP group and 75.93 (±5.73) in the IMIP group. Significant effect of treatment modus in favour of the IMIP and gender in favour of males and implant position was noted (p<0.05). Conclusions SIS following a IMIP protocol after 6-8 months is comparable to LIP protocol after 2-3 months. A minor ISQ outcome difference in favour of the IMIP protocol can be attributed to a difference in hard tissue alteration during healing of the xenograft part. Key words:Secondary implant stability, RFA, Osstell Mentor, variable thread implants, Nobel Active, Bio-Oss, immediate implant placement, late implant placement, non-submerged healing, gap.

Updated secondary implant stability data of two dental implant systems : a retrospective cohort study

Background At present, updated secondary implant stability data generated by actual versions of resonance frequency analysis (RFA) and mobility measurement (MM) electronic devices of 2 different implant systems with actual manufactured surfaces seem to lack and/or are incomplete. Material and Methods Secondary implant stability data based on both RFA and MM measurements were collected and analyzed from 44 formerly treated patients (24 f, 20 m) that received either Ankylos Cellplus (Ø3.5mm) (A) (n=36) or Straumann regular neck SLA tissue level (Ø4.1mm) (S) (n=37) implants in posterior positions of both jawbones (total number= 72). These results were interpretated in view of formerly published data. Results Estimated RFA outcomes (mean±SD) for A implants were of 81.23 (±0.65) (LP) - 76.15 (±1.57) (UP) isq; for S implants 76.15 (±1.48) (LP) - 73.88 (±2.34) (UP) isq. Estimated MM outcomes for A implants were (-4.0) (±0.23) (LP) - (-3.2) (±0.33) (UP) ptv; for S implants (-5.15) (±0.39) (LP) - (-4.4) (±0.84) (UP) ptv. According to GEE statistical modelling, implant type and – position seems to influence the outcome variables (p<0.05), gender and implant length did not (p >0.05). Conclusions Secondary implant stability values, recorded with current RFA and MM devices, of A Cellplus implants are provided for the first time. A difference of 14.7-9.7 isq values was noted for CellPlus versus TPS S implants recorded with a cabled RFA device. This study supports the assumption that RFA outcomes generated with first generation RFA devices are different from those obtained with current RFA devices, meaning that its use in reviews need caution and correction. Key words:Secondary implant stability, resonance frequency analysis, Periotest, Osstell Mentor, Straumann, Ankylos, CellPlus, SLA.

Fine grained osseointegrative coating improves biocompatibility of PEEK in heterotopic sheep model

Background and aim Polyetheretherketone (PEEK) materials already have been used successfully in orthopedic and especially spine surgery. PEEK is radiolucent and comparable with bone regarding elasticity. However, PEEK is inert and the adhesion of PEEK implants to bone tissue proceeds slowly because of their relatively low biocompatibility. The aim of the study is to evaluate the effect of titanium and CaP coating on the adhesion of bone tissue. Material and Methods Six adult sheep (body weight 57.6 ± 3.9 kg) were included in this study. Three different types of cylindrical dowels (12 mm length x 8 mm diameter) were implanted in long bones (tibia and femur): PEEK dowels without coating (the control group), and PEEK dowels with a nanocoating of calcium phosphate (CaP group) or titanium (titanium group). Animals were sacrificed after 6, 12 and 26 weeks. Dowels were explanted for micro CT and histology. Results Bone implant contact (BIC) ratio was significantly higher in the titanium versus control groups in the 6 to 12 weeks period (p = 0.03). The ratio between bone volume and tissue volume (BV/TV) was significantly higher in titanium versus control in the 6 to 12 weeks period (p = 0.02). A significant correlation between BIC and BV/TV was seen (r = 0.85, p < 0.05). Conclusion Coating of PEEK dowels with a nanocoating of titanium has beneficial effects on adhesion of bone tissue.