Entity

Time filter

Source Type

Antwerpen, Belgium

Luukkonen T.,University of Oulu | Luukkonen T.,Kajaani University of Applied Sciences | Heyninck T.,Plantijn College | Ramo J.,University of Oulu | And 2 more authors.
Water Research | Year: 2015

The use of organic peracids in wastewater treatment is attracting increasing interest. The common beneficial features of peracids are effective anti-microbial properties, lack of harmful disinfection by-products and high oxidation power. In this study performic (PFA), peracetic (PAA) and perpropionic acids (PPA) were synthesized and compared in laboratory batch experiments for the inactivation of Escherichia coli and enterococci in tertiary wastewater, oxidation of bisphenol-A and for corrosive properties. Disinfection tests revealed PFA to be a more potent disinfectant than PAA or PPA. 1.5 mg L-1 dose and 2 min of contact time already resulted in 3.0 log E. coli and 1.2 log enterococci reduction. Operational costs of disinfection were estimated to be 0.0114, 0.0261 and 0.0207 €/m3 for PFA, PAA and PPA, respectively. Disinfection followed the first order kinetics (Hom model or S-model) with all studied peracids. However, in the bisphenol-A oxidation experiments involving Fenton-like conditions (pH = 3.5, Fe2+ or Cu2+ = 0.4 mM) peracids brought no additional improvement to traditionally used and lower cost hydrogen peroxide. Corrosion measurements showed peracids to cause only a negligible corrosion rate (<6 μm year-1) on stainless steel 316L while corrosion rates on the carbon steel sample were significantly higher (<500 μm year-1). © 2015 Elsevier Ltd. Source


Winter C.,Vrije Universiteit Brussel | Van Acker F.,Plantijn College | Bonduelle M.,Vrije Universiteit Brussel | Van Berkel K.,Vrije Universiteit Brussel | And 3 more authors.
Human Reproduction | Year: 2016

STUDY QUESTION Do preimplantation genetic diagnosis (PGD) couples experience higher levels of stress during pregnancy and the perinatal period compared with couples who conceive spontaneously (SC) or with ICSI? SUMMARY ANSWER PGD couples did not experience more psychological stress during pregnancy and beyond than ICSI or SC couples. WHAT IS ALREADY KNOWN Previous studies have shown that assisted reproduction technology (ART) couples are more prone to pregnancy-related anxieties than SC couples, but display depressed feelings to an equal or lesser extent. However, only one study has focused on a female PGD sample, which may be a more vulnerable group than other ART groups, due to the potentially complex hereditary background, adverse childhood experiences and losses. In that study, PGD women experienced a reduction in state anxiety, and maternal-antenatal attachment did not differ from normative data. Unfortunately, no data exist on pregnancy-related anxiety, depression and parental-antenatal attachment. Valuable information from both parents (e.g.: couples) is also lacking. STUDY DESIGN, SIZE, DURATION For this longitudinal prospective study questionnaire, data from 185 women and 157 men (157 couples) were collected between February 2012 until April 2014. Data were analysed using multilevel analysis. The couples conceiving after PGD, ICSI or SC were followed from the first trimester of the pregnancy until the third month post-partum. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 60 PGD, 58 ICSI and 69 SC couples were initially recruited by various departments of Universitair Ziekenhuis Brussel (UZ Brussel). At each trimester (T1: 12-14 weeks, T2: 20-22 weeks, T3: 30-32 weeks) of pregnancy, depression (EPDS), pregnancy-related anxieties (PRAQ) and parental-antenatal attachment (M/PAAS) were recorded. At T4 (3 months post-partum), depression (EPDS) was assessed again. In the first trimester (T1) broad socio-demographic data and at T4 perinatal health data of both mother and child were recorded. Differences between conception groups over time were analysed using multilevel analyses, taking into account covariation between measurements and within couples. Several perinatal covariates as well as social desirability, coping and adult attachment style were controlled for. MAIN RESULTS AND THE ROLE OF CHANCE All three conception groups had similar scores for depression during pregnancy and beyond. Also, pregnancy-related anxiety scales did not differ among the three groups. All groups also followed a similar trajectory in time regarding their scores for anxiety, depression and parental-antenatal attachment. ART groups did not give more socially desirable answers than SC controls. The subsequent moderators: coping and adult attachment style did not add any relevant information. No interaction effects occurred between gender and conception groups. LIMITATIONS, REASONS FOR CAUTION The participants were Caucasian, Dutch-speaking couples, with medium to high socio-economic status, from a single centre. Our data should be replicated by multicultural and multicentre studies. Furthermore, the inclusion of an additional control group of couples who did not opt for PGD but for prenatal diagnosis may point to the most beneficial strategy for the couple. WIDER IMPLICATIONS OF THE FINDINGS PGD parents invest a similar amount of time and emotion in their future children compared with controls. This implies that successful PGD treatment makes an important psychological contribution towards the well-being of couples given their complex hereditary and family backgrounds. STUDY FUNDING/COMPETING INTEREST(S) This research project was funded by grants from the internal research council of the Vrije Universiteit Brussel (OZR), the Flemish Fonds Wetenschappelijk Onderzoek (FWO) and the Wetenschappelijk Fonds Willy Gepts (WGFG). UZ Brussel and the Centre for Medical Genetics have received several educational grants for organizing the data collection, from IBSA, Ferring, Organon, Shering-Plough, Merck and Merck Belgium. M.B. has received consultancy and speaker's fees from Organon, Serono Symposia and Merck. © 2016 The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. Source


Vandenbrouck T.,University of Antwerp | Vandenbrouck T.,Apeiron Team Nv | Dom N.,University of Antwerp | Novais S.,University of Aveiro | And 5 more authors.
Comparative Biochemistry and Physiology - Part D: Genomics and Proteomics | Year: 2011

In this study, gene transcription profiling in combination with the assessment of systemic parameters at individual and population levels were applied to study the (toxic) effects induced through temperature stress in the presence or the absence of an additional chemical stressor (nickel) in Daphnia magna. It was illustrated that lower temperatures were mainly characterized by a reduction of growth and lipid content, while higher temperatures caused an increase of both endpoints. Many of the differentially regulated transcripts could be correlated with processes affected at higher hierarchical levels of biological organization. Gene clusters with probable roles in producing offspring (peak expression at 22 °C), enhancing the metabolic rate (temperature related expression) and translational processes (increased expression at 14 °C) were identified. However, it was not possible to pinpoint a specific subset of genes, exclusively responding to temperature or nickel and allowing a retrospective identification of the particular stressor. Overall, extreme temperatures caused a higher level of stress in the organisms in comparison to nickel exposure. Moreover, organisms subjected to the natural stressor appeared to be less capable of dealing with the additional chemical stressor and as a result activate or repress more gene pathways. © 2011 Elsevier Inc. All rights reserved. Source


Van Acker F.,Plantijn College | Vermeulen M.,Open University of the Netherlands | Kreijns K.,Open University of the Netherlands | Lutgerink J.,University of Management and Technology | Van Buuren H.,Open University of the Netherlands
Computers in Human Behavior | Year: 2014

In the current paper we report on a study regarding teachers' sharing behavior regarding their Open Educational Resources (OER) in the Netherlands. Little is known about how many teachers actually share their learning materials and, therefore, an attempt was made to estimate the number of Dutch teachers and the types of OER they share. Second, we tried to find out whether knowledge sharing self-efficacy facilitated, and evaluation apprehension and trust inhibited teachers to share OER in two different contexts of sharing behavior; sharing with colleagues at their school (interpersonal sharing) and sharing with the public through Internet (Internet sharing). A survey among 1568 teachers from primary to higher education was undertaken to test the relative importance of knowledge sharing self-efficacy, evaluation apprehension and trust in determining Dutch teachers' intention to share. The results showed that a large proportion of the Dutch teachers shared their OER, but that this sharing was limited to learning materials with low complexity (e.g., texts or images). Moreover, sharing occurred twice as much interpersonally than via websites. Our hypothesis that evaluation apprehension is significantly related to sharing behavior as well as the intention to share was not confirmed. Self-efficacy to share knowledge did, however, explain some of the differences in sharing behavior and in the intention to share of Dutch teachers, although the variables under study accounted only for a small amount of variance. Our findings should thus be replicated in further studies and other variables should be considered that could effectively predict OER sharing behavior of teachers. © 2014 Elsevier Ltd. All rights reserved. Source


Hardy L.,Institute of Tropical Medicine | Hardy L.,Ghent University | Jespers V.,Institute of Tropical Medicine | Dahchour N.,Institute of Tropical Medicine | And 5 more authors.
PLoS ONE | Year: 2015

Bacterial vaginosis (BV), a condition defined by increased vaginal discharge without significant inflammation, is characterized by a change in the bacterial composition of the vagina. Lactobacillus spp., associated with a healthy vaginal microbiome, are outnumbered by BV-associated organisms. These bacteria could form a polymicrobial biofilm which allows them to persist in spite of antibiotic treatment. In this study, we examined the presence of Gardnerella vaginalis and Atopobium vaginae in vaginal biofilms using Peptide Nucleic Acid (PNA) probes targeting these bacteria. For this purpose, we developed three new PNA probes for A. vaginae. The most specific A. vaginae probe, AtoITM1, was selected and then used in an assay with two existing probes, Gard162 and BacUni-1, to evaluate multiplex FISH on clinical samples. Using quantitative polymerase chain reaction (qPCR) as the gold standard, we demonstrated a sensitivity of 66.7% (95% confidence interval: 54.5%-77.1%) and a specificity of 89.4% (95% confidence interval: 76.1%-96%) of the new AtoITM1 probe. FISH enabled us to show the presence of a polymicrobial biofilm in bacterial vaginosis, in which Atopobium vaginae is part of a Gardnerella vaginalis-dominated biofilm. We showed that the presence of this biofilm is associated with high bacterial loads of A. vaginae and G. vaginalis. © 2015 Hardy et al. Source

Discover hidden collaborations