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STUDY QUESTION Are cumulative pregnancy rates better if supernumerary embryos are vitrified on Day 5/6 instead of Day 3? SUMMARY ANSWER The results do not show a significant difference in cumulative pregnancy rates between the Day 3 and Day 5/6 vitrification groups. WHAT IS KNOWN ALREADY Pregnancy and live birth rates following IVF or ICSI treatment are higher after extended embryo culture and blastocyst transfer (Day 5/6) compared to cleavage-stage (Day 3) transfer. Cumulative pregnancy rates from one oocyte retrieval (OR) cycle show no significant difference after fresh and frozen embryo transfers, but only one study has used vitrification for the cryopreservation of supernumerary embryos while four studies have used a slow freezing protocol. STUDY DESIGN, SIZE, DURATION Our prospective randomized controlled trial was performed in an academic centre between January 2018 and August 2020. Patients were randomized into vitrification Day 3 (n = 80) or Day 5/6 (n = 81) groups. The primary outcome was the cumulative ongoing pregnancy rate (cOPR), considering only the first pregnancy for each couple. The power calculation revealed that 75 patients were required in each group, when assuming a 50% cOPR with four embryo transfers in the vitrification Day 3 group vs two transfers in the vitrification Day 5/6 group. PARTICIPANTS/MATERIALS, SETTING, METHODS Patients <38 years undergoing their first or second OR cycles were randomized at the start of the first cycle. Up to two cycles were included in the analysis. A fresh embryo transfer was performed on Day 3. Supernumerary embryos (with ≥6 cells, <25% fragmentation, and equal blastomeres) or blastocysts (with expansion grade ≥2 with inner cell mass and trophectoderm score A/B) were vitrified on Day 3 or Day 5/6, respectively, and then transferred at a later date. A time-to-event analysis was performed with the patient's first ongoing pregnancy as the event of interest and the number of embryo transfers as the time component. The statistical comparison was performed by a Cox proportional hazards model. Cumulative costs of vitrification on Day 3 vs Day 5/6 were explored and compared using Mann–Whitney U tests. MAIN RESULTS AND THE ROLE OF CHANCE By December 2021, 233 transfers (96 fresh and 137 frozen) in 77 patients were performed in the vitrification Day 3 group and 201 transfers (88 fresh and 113 frozen) in 77 patients were performed in the vitrification Day 5/6 group. The time-to-event analysis did not show a difference between the two arms with regard to the patient's first ongoing pregnancy as the primary study outcome (hazard ratio [HR] 1.25, 95% CI 0.82; 1.92, P = 0.30). The cumulative ongoing pregnancy rate after eight transfers (from one or two ORs) was 57% in the vitrification Day 3 group vs 58% in the vitrification Day 5/6 group. The median number of embryo transfers until a pregnancy was achieved was five vs four, respectively, in the vitrification Day 3 group vs the Day 5/6 group. Similar results were found for the secondary study outcome, i.e. clinical pregnancy with foetal heart rate (HR 1.19, 95% CI 0.78; 1.80, P = 0.41). The cumulative clinical pregnancy rate (cCPR) after eight embryo transfers was 62% in the vitrification Day 3 group vs 59% in the vitrification Day 5/6 group. The median number of transfers until a pregnancy was achieved was four in both groups. The healthcare consumption pattern differed between the two groups and we observed higher costs for the vitrification Day 3 group compared to the vitrification Day 5/6 group, although these differences were not statistically significant. LIMITATIONS, REASONS FOR CAUTION Although our power calculation revealed that only 75 patients were needed in each study group (β = 0.87, α < 0.05), the numbers were low. Also, different numbers of single and double embryo transfers were performed between the two groups, which may have affected the results. The cost analysis was performed on a subset of the patients and is therefore exploratory. WIDER IMPLICATIONS OF THE FINDINGS Our study shows no difference in the cumulative pregnancy rate nor costs after fresh and frozen embryo transfers of at most two sequential OR cycles between the Day 3 and Day 5/6 vitrification groups; however, obstetric and perinatal outcomes should be taken into account to determine the best strategy. STUDY FUNDING/COMPETING INTEREST(S) This study was funded as an investigator-sponsored study of S.D. by Merck nv/sa Belgium, an affiliate of Merck KGaA, Darmstadt, Germany, and by Gedeon Richter Benelux (PA18-0162). The authors declare no conflict of interest related to this study. TRIAL REGISTRATION NUMBER NCT04196036. TRIAL REGISTRATION DATE 15 January 2018. DATE OF FIRST PATIENT'S ENROLMENT 15 January 2018. [ABSTRACT FROM AUTHOR]

Digital game-based learning builds on the general characteristics of games. The incentive system (points, scores, stars, levels, and performance feedback) integrates design elements to keep a learner engaged. In the work described here, we investigated which elements of the incentive system design—rewards, penalties, or feedback—have the potential to trigger students' motivation to play the game. We used eye tracking of eight primary school children, aged 8–11 years, as they interacted with the incentive system of a mathematics game-based item and its specific design, followed by a semi-structured interview. Eye-tracking results show that students paid minimal visual attention to the incentive system during the game, regardless of their level of performance in the game or their age group. The feedback at the end of the game attracted more of their visual attention and provided a good opportunity to inform them about their performance. The semi-structured interviews revealed a high level of self-reported excitement about playing the game, mainly related to the design of the incentive system. Elements of the incentive system triggered students' wish for student-to-student competition, which has been shown in the literature on traditional tangible rewards to stifle intrinsic motivation under certain conditions. The results of this study show that the design of the incentive system has the potential to promote extrinsic motivation with the game through rewards and penalties, and open the reflection on its possible spillover effect on intrinsic motivation in digital game-based learning. [ABSTRACT FROM AUTHOR]

Background: The large-scale International Computer and Information Literacy Study (2018) has an interesting finding concerning Luxembourg teachers. Luxembourg has one of the highest reported level of technology-related resources for teaching and learning, but a relatively lower reported use of ICT in classroom practice. Methods: ICT innovation requires a high initial level of financial investment in technology, and Luxembourg has achieved this since 2015. Once the necessary financial investment in ICT technology has been made, the key question is what else matters to increase the use of ICT in teaching. To identify the relevant factors, we used the "Four in Balance" model, aimed explicitly at monitoring the implementation of ICT in schools. Results: Using data for 420 teachers in Luxembourg, we identify that within such a technology-driven approach to digitalization, teachers' vision of ICT use in teaching, level of expertise, and the use of digital learning materials in class are significant support factors. Leadership and collaboration, in the form of an explicit vision of setting ICT as a priority for teaching in the school, also prove to be important. Conclusions: Through these findings, we show that the initial investment in school infrastructure for ICT needs to be associated in its implementation with teachers' ICT-related beliefs, attitudes, and ICT expertise. [ABSTRACT FROM AUTHOR]

Background As work and health are closely interlinked, it is important to carefully monitor employees. However, limited resources restrict in-depth follow-up. Aims This study was aimed to develop a low-cost screening instrument for employees' overall health status, that can be used across industries and that allows triaging workers to in-depth health surveillance in case of indications of health or functioning problems. Methods We developed a new questionnaire-based algorithm built on multiple predictors to assess the need for further follow-up. We used a systematic review, Delphi panel (n = 9) and focus group (n = 5) to determine the predictors, tested for language pitfalls in a pilot study and evaluated the questionnaire's validity in two separate studies. Study 1 (n = 60) analysed the discriminatory power of the instrument by comparing it to the assessment of an occupational physician in a sample of employees from diverse occupational settings. Study 2 (n = 869) appraised the factor structure and internal consistency of the screening tool in a sample of employees from the hospital sector. Results Risk factors, current physical and mental health, functioning, absenteeism, job satisfaction and lifestyle were identified as the most relevant predictors. Study 1 showed the survey had good criterion validity (area under the curve = 0.72). Study 2 (N = 869, 28% response) demonstrated the internal consistency (Cronbach's α = 0.94), and a factor analysis confirmed a second-order factor structure with adequate model fit (comparative fit index = 0.96, root mean square error of approximation = 0.04 and standardized root mean square residual = 0.07). Conclusions This questionnaire can be used to triage workers for occupational health follow-up and can, additionally, be useful to describe the epidemiology of work-related illness. [ABSTRACT FROM AUTHOR]

Introduction: In several countries1, direct access to physiotherapy (PT) for acute low back pain (aLBP) had a positive impact on clinical outcomes2 and health-care usage and costs3. The aim of this study is to investigate the effect of direct PT access on pain, disability and costs compared to usual care by the general practitioner (GP) for aLBP within the Belgian care system. Methods: Six hundred adults (French-speaking: n = 300; Dutch-speaking: n = 300) with aLBP (>24 hours and <6 weeks) will be recruited and semi-randomly allocated to the usual care or the direct PT pathway in this ethically approved study (CME2021/066). Primary outcomes include pain intensity, pain location and disability. Secondary, a cost-effectiveness analysis will evaluate the patient-and societal costs associated with aLBP and its treatment. Other secondary outcomes include beliefs and cognitions related to LBP, quality of life, work disability, amount of flare ups and perceived effect of change. All outcomes will be evaluated through validated questionnaires at baseline, during and at the end of intervention and at 3 months, 1 and 2 years following enrolment. Effects and relations will be investigated using, respectively, linear mixed models and multiple linear regression. Results: It is hypothesized that direct PT access will result in higher reductions in pain and disability and lower costs compared to usual care for aLBP. Discussion: The study results will be used to optimize the Belgian care pathway for aLBP. Process evaluation: Challenges to this trial include an unbiased organization within the Belgian care and political system and patient recruitment in the direct PT pathway. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) is a promising carrier material for oral delivery of biomolecules such as proteins and drugs. Ways to increase the loading of such molecules on HA will lead to better nanomedicine. This study reports the surface functionalisation of HA particles using the mussel inspired molecules dopamine (DA) and 3,4-dihydroxy-L-phenylalanine (DOPA), in order to increase protein loading. The adsorption mechanisms are discussed based on the adsorption isotherms, zeta potential, thermal analysis and theoretical models. Results show that DA functionalisation enhanced the loading, while DOPA functionalisation was ineffective. [ABSTRACT FROM AUTHOR]

In this paper, the abatement of adsorbable halogenated organic compounds (AOX) from an industrial wastewater containing relatively high chloride concentrations by a combined chemical and biological oxidation is assessed. For chemical oxidation, the O3/UV, H2O2/UV and photo-Fenton processes are evaluated on pilot scale. Biological oxidation is simulated in a 4 h respirometry experiment with periodic aeration. The results show that a selective degradation of AOX with respect to the matrix compounds (expressed as chemical oxygen demand) could be achieved. For O3/UV, lowering the ratio of O3 dosage to UV intensity leads to a better selectivity for AOX. During O3-based experiments, the AOX removal is generally less than during the H2O2-based experiments. However, after biological oxidation, the AOX levels are comparable. For H2O2/UV, optimal operating parameters for UV and H2O2 dosage are next determined in a second run with another wastewater sample. [ABSTRACT FROM AUTHOR]

The permeability of metallic and ceramic open-cell foams prepared by the gelcasting technique was assessed by fitting of Forchheimer’s equation to experimental pressure drop curves. The ceramic composition was based on pure hydroxyapatite, while the metallic composition was based on titanium metal. Experimental Darcian ( k) and non-Darcian ( k) permeability constants displayed values in the range 0.40–3.24 × 10 m and 3.11–175.8 × 10 m respectively. Tortuosity was evaluated by gas diffusion experiments and ranged from 1.67 to 3.60, with porosity between 72 and 81% and average hydraulic pore size between 325 and 473 μm. Such features were compared to data reported in the literature for cancellous bones and synthetic scaffolds for bone graft. A detailed discussion concerning the limitations of Darcy’s law for fitting laboratory data and for predicting fluid flow through scaffolds in real biomedical applications is also performed. Pore size was obtained by image analysis and was also derived from permeation-absorption-diffusion experiments. In both cases, values were within the range expected for porous scaffolds applications. [ABSTRACT FROM AUTHOR]

Because bone tissue engineering (TE) strategies encounter patient specificities, like site of implantation and different bone turnover rate, scaffolds with tunable characteristics are required. With this regard, custom made open porous calcium phosphate (CaP) structures with variable chemical and structural compositions were produced using an optimised gel casting technique. The phase composition was altered by changing the initial hydroxyapatite (HA) to β-tricalcium phosphate (β-TCP) powder ratio. After sintering, an HA/β-TCP ratio between 100 : 0 and 0 : 100 was predictably attained. Average pore sizes ranged from 182 to 466 m m and corresponded to porosity values of respectively 71 and 86%. Mechanical strength and dynamic E-modulus respectively decreased with decreasing HA content from 10·1 to 0·4 MPa and 9·46 to 0·27 GPa. It was concluded that this optimised gel casting method enables the production of CaP scaffolds with a custom made HA/β-TCP ratio with variable pore size, porosity and corresponding mechanical strength. [ABSTRACT FROM AUTHOR]

With the aim to understand and estimate the economic impact of outbreaks of community-acquired infections, we performed a review focusing on hepatitis A outbreaks, and retained 13 papers that had collected relevant cost information during such outbreaks. All costs in this article are expressed in USD, year 2007 values. The costs of hepatitis A outbreaks ranged from USD140 000 to US36 million, and the costs per case in an outbreak situation ranged from USD3824 to USD200 480. These costs were typically found to be substantially higher than estimates from cost-of-illness studies (i.e. costs for sporadic cases) and estimates used in cost-effectiveness analyses, mostly because of costly outbreak-control measures. Post-exposure prophylaxis is a major cost factor, especially for food-borne outbreaks. As a result of the increasing proportion of those susceptible to hepatitis A in low-incidence countries, future outbreaks could, on average, increase in size. The increasing occurrence of hepatitis A cases in outbreak situations and the associated control costs should appropriately be accounted for in economic evaluations of vaccination programmes in low-incidence countries. In order to do this, more studies documenting such outbreak-control strategies in terms of costs and resource use are needed. [ABSTRACT FROM AUTHOR]

The most conventional manufacturing route for ceramic foams with open cells consists of coating reticulated polyurethane foams. The resulting material has well defined cell size, but suffers from low mechanical strength owing to the presence of hollow struts. As a result, the performance and utilisation of ceramic foams manufactured by this method are limited in certain applications. One solution to overcoming this inherent disadvantage is to use a stronger ceramic coating material and to ameliorate the wetting of the polyurethane template. Such a material is reaction bonded Al2O3 (RBAO), which has high mechanical strength as a result of its fine grain structure, with less or even without glassy phases at the grain boundaries. The present work demonstrates the feasibility of producing strong ceramic foams by using a reaction bonded modified replica technique starting from polyurethane templates varying in both composition and cell size distribution. [ABSTRACT FROM AUTHOR]

Phase demixing is evaluated as a possible explanation for the anomalous temperature dependence of the Pt segregation at the Pt50Rh50(511), Pt25Rh75(110) and Pt25Rh75(100) surfaces. Calculations are performed in the quasichemical approximation and a broken bond scheme. Although the calculations based on systematic demixing tend to overestimate the surface enrichment, the qualitative agreement appears to be rather good. [ABSTRACT FROM AUTHOR]

The effect of non-Faradaic electrochemical modification of catalytic activity (NEMCA) was investigated for the case of CH oxidation on a Pt polycrystalline catalyst film also acting as a working electrode in a galvanic cell of the type: In addition to proton conduction, CaZrInO is known to exhibit oxygen and hole conduction. Proton conduction predominates over the temperature range, 380 to 460 °C, of the present investigation. It was found that negative current application, i.e. proton supply to the Pt catalyst film causes up to 500% reversible enhancement to the rate of CH oxidation. The catalytic rate increase is up to 20,000 higher than the rate, -I/F, of proton supply to the catalyst. The observed phenomena are discussed within the framework of previous electrochemical promotion (NEMCA) studies. [ABSTRACT FROM AUTHOR]

Magnesium sensitive probes were constructed and tested in different melts of commercial aluminium-magnesium alloys. The probes were composed of a porous magnesium oxide one closed end tube or thimble to which a magnesium conducting salt is impregnated. The activity of magnesium in the aluminium-magnesium melt was determined with report to a pure magnesium reference contained in the inside of the thimble and sealed from the surrounding atmosphere and melt by zirconia based cement. Measurements were conducted in various commercial aluminium-magnesium alloys under inert atmosphere as well as in air. [ABSTRACT FROM AUTHOR]

The preparation and characterization of porous ceramic membranes is presented. These membranes consist of a macroporous support system, with or without a mesoporous intermediate layer, and a microporous top layer. For the macroporous support membranes two manufacturing routes are described: a conventional and a RBAO (Reaction Bonded Aluminium Oxide) route. The mesoporous γ-Al2O3 layer is obtained by means of a sol-gel dipcoating technique. Three microporous top layers are considered: SiO2, Al2O3-pillared montmorillonite and Laponite. These top layers have different pore structures which results in different gas transport properties. A SiO2 membrane can be used for H2 removal from a gas mixture. Al2O3-pillared montmorillonite and Laponite membranes do not show specific gas separation properties. Dehydration of water/2-propanol mixtures by means of pervaporation also proved a different behavior for these microporous membranes. [ABSTRACT FROM AUTHOR]

In the eighties, Iwahara discovered that doped Sr and Ba cerates show significant proton conduction, at high temperature, and in hydrogen- or water-containing atmosphere [1]. Begin '90 it was proved that also doped zirconates (Sr, Ba, Ca) join this family of proton conducting perovskites [2]. Within this group, indium doped CaZrO is one of the more interesting materials for applications, being mechanically and chemically particularly stable, and producible in very dense form. Specifically, it was already succesfully incorporated in a hydrogen sensor for liquid aluminium [3]. In principle, this sensor works as a simple electrochemical hydrogen concentration cell described by Nernst. However, as already remarked phenomenologically from the beginning [1], a hydrogen concentration cell using these perovskites shows the theoretically predicted emf, only in the presence of humidity. In this paper we want to go deeper into the reasons for this phenomenon. [ABSTRACT FROM AUTHOR]

We report a new mutation in the sterol 27-hydroxylase (CYP 27) gene in a Dutch family with cerebrotendinous xanthomatosis: a G→A transition in the splice donor site in intron 4. This mutation leads to skipping of exon 4, resulting in a loss of 66 amino acids in the CYP 27 enzyme molecule. [ABSTRACT FROM AUTHOR]

This report concerns two new mutations in the sterol 27-hydroxylase gene in two patients with cerebrotendinous xanthomatosis (CTX). In a Surinam-Creole patient (patient A), a G deletion on position cDNA 546/547 in exon 3 led to a frameshift and the introduction of a premature termination codon. In a Dutch patient (patient B), a C→T transition at position 496 in exon 3 also led to a premature termination codon. Patient A was homozygous for the mutation, whereas patient B was compound heterozygous, a C→T transition also being found in exon 6 at position 1204. The two new mutations were confirmed by restriction analysis with the restriction enzymes FokI and MaeI, respectively. [ABSTRACT FROM AUTHOR]