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Invasieve exotische kreeften zijn inmiddels een groot probleem geworden in Nederland. Uit verschillende onderzoeken blijkt dat ze het ecosysteem en de waterkwaliteit ernstige schade toebrengen. Daarnaast graven ze - net als muskusratten - holen in oevers waardoor ze een veiligheidsrisico kunnen vormen.

Item does not contain fulltext, Recently, an intronic biallelic (AAGGG)(n) repeat expansion in RFC1 was shown to be a cause of CANVAS and adult-onset ataxia in multiple populations. As the prevalence of the RFC1 repeat expansion in Dutch cases was unknown, we retrospectively tested 9 putative CANVAS cases and two independent cohorts (A and B) of 395 and 222 adult-onset ataxia cases, respectively, using the previously published protocol and, for the first time optical genome mapping to determine the size of the expanded RFC1 repeat. We identified the biallelic (AAGGG)(n) repeat expansion in 5/9 (55%) putative CANVAS patients and in 10/617 (1.6%; cohorts A + B) adult-onset ataxia patients. In addition to the AAGGG repeat motif, we observed a putative GAAGG repeat motif in the repeat expansion with unknown significance in two adult-onset ataxia patients. All the expanded (AAGGG)(n) repeats identified were in the range of 800-1299 repeat units. The intronic biallelic RFC1 repeat expansion thus explains a number of the Dutch adult-onset ataxia cases that display the main clinical features of CANVAS, and particularly when ataxia is combined with neuropathy. The yield of screening for RFC1 expansions in unselected cohorts is relatively low. To increase the current diagnostic yield in ataxia patients, we suggest adding RFC1 screening to the genetic diagnostic workflow by using advanced techniques that attain long fragments.

Ademen met de klimaatcrisis; ecologisch – sociaal – spiritueel was het thema van de Internationale biodynamische conferentie, die begin februari 2021 online werd georganiseerd vanuit Dornach (Zw). Dit rapport bevat het verslag van de conferentie – in woord en beeld. Over hoe het klimaat zich in miljoenen jaren heeft ontwikkeld, de rol van de landbouw en de koe, de boer als klimaatbeschermer, de aarde als levend organisme, en nog veel meer.

The present study aimed to investigate whether positive and negative affective relationships with parents predicted sibling bullying victimisation. To answer this question, the present study made use of a sample of 780 students in their first year as high schoolers in the Netherlands. A multiple regression analyses showed that the negative affective relationship with the mother and/or the father was a significant predictor for sibling bullying victimisation. The positive affective relationship with the father was a significant predictor, predicting less sibling bullying, while the positive affective relationship with the mother showed no effect. The most important predictor for sibling bullying was the negative affective relationship with the father. This difference could be explained by leadership theory, it is possible that children copy their fathers authoritarian behaviour. Set against the findings of this study, it is important that researchers further investigate the exact role of fathers.

We developed a hybrid Monte Carlo self-consistent field technique to model physical gels composed of ABA triblock copolymers and gain insight into the structure and interactions in such gels. The associative A blocks of the polymers are confined to small volumes called nodes, while the B block can move freely as long as it is connected to the A blocks. A Monte Carlo algorithm is used to sample the node configurations on a lattice, and Scheutjens-Fleer self-consistent field (SF-SCF) equations are used to determine the change in free energy. The advantage of this approach over more coarse grained methods is that we do not need to predefine an interaction potential between the nodes. Using this MC-SCF hybrid simulation, we determined the radial distribution functions of the nodes and structure factors and osmotic compressibilities of the gels. For a high number of polymers per node and a solvent-B Flory-Huggins interaction parameter of 0.5, phase separation is predicted. Because of limitations in the simulation volume, we did however not establish the full phase diagram. For comparison, we performed some coarse-grained MC simulations in which the nodes are modeled as single particles with pair potentials extracted from SF-SCF calculations. At intermediate concentrations, these simulations gave qualitatively similar results as the MC-SCF hybrid. However, at relatively low and high polymer volume fractions, the structure of the coarse-grained gels is significantly different because higher-order interactions between the nodes are not accounted for. Finally, we compare the predictions of the MC-SCF simulations with experimental and modeling data on telechelic polymer networks from literature.

Confidential thesis, only summary available., Mechanical, Maritime and Materials Engineering, Marine and Transport Technology, Design, Production and Operations

‘Dankzij kierbesluit na 40 jaar 1e glasaal #Kinderdijk #Alblasserwaard aangetroffen #Paling weet weg weer te vinden!’ Dit bericht werd op 19 april 2016 door waterschap Rivierenland gepubliceerd op Twitter en werd overgenomen door diverse media.

Zuid-Holland is een van de meest waterrijke provincies van Nederland: rivieren die er hun weg naar zee vinden, veenplassen verbonden door een netwerk van waterlopen, polders met duizenden kilometers sloot, stadswateren, duin- en recreatieplassen. Het is de belangrijkste toegangspoort voor trekvissen van het Rijn- en Maasstroomgebied, zoals de zalm. Ruim negentig procent van de Nederlandse zoetwatervisfauna leeft hier.

Zuid-Holland is een van de waterrijkste provincies van Nederland: rivieren die er hun weg naar zee vinden, veenplassen verbonden door een netwerk van waterlopen, polders met duizenden kilometers sloot, stadswateren en duin- en recreatieplassen. Het is de belangrijkste toegangspoort voor trekvissen van het Rijn- en Maasstroomgebied, zoals de Atlantische zalm. Ruim 90% van de Nederlandse zoetwatervissoorten komt hier voor. Er was echter weinig bekend over de verspreiding van de vele vissoorten die de provincie rijk is. Om hier verandering in te brengen is in 2010 gestart met een atlasproject, waarbinnen is samengewerkt door een groot aantal organisaties. Het ‘atlasproject’ werd afgelopen voorjaar afgerond met de presentatie van het boek ‘De Vissen van Zuid-Holland’. In dit artikel wordt een aantal van de belangrijkste resultaten belicht.