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We present a comprehensive micro- and macrorheological study of the effect of weak depletion attraction (Ψdep ≈ 1–10 kBT) on dense colloidal suspensions stabilized by short-range repulsive interactions. We used aqueous polymer dispersions as model system and demonstrated the unique capabilities of multiple particle tracking (MPT) to disclose structural changes in such technically important systems exhibiting many characteristic features of hard sphere systems. Below the hard sphere freezing point ϕc, viscosity increases monotonically with increasing Ψdep due to the transition from a fluid to a fluid/crystalline and finally to a gel state. Above ϕc, increasing attraction strength first results in a viscosity reduction corresponding to the formation of large, permeable crystals and then in a viscosity increase when a network of dense, small crystals forms. The fraction of the fluid and crystal phase, particle concentration in each phase as well as the modulus of the micro-crystals are obtained, the latter decreases with Ψdep. Above the colloidal glass transition strong heterogeneities and different local particle mobility in the repulsive and attractive arrested states are found. Particles are trapped in the cage of neighboring particles rather than in an attractive potential well. The intermediate ergodic state exhibits uniform tracer diffusivity.

Uni-directional wave models are used to study wave groups that appear in wave tanks of hydrodynamic laboratories; characteristic for waves in such tanks is that the wave length is rather small, comparable to the depth of the layer. In second-order theory, the resulting Nonlinear Schrödinger (NLS) equation for the envelope of the wave group contains the dispersion of the group velocity multiplying the linear term and a ‘gen-coefficient’ that results from mode generation multiplying the nonlinear term. The signs of these coefficients determine whether experimentally relevant wave groups are possible or not. If the dispersion is modelled in such a way that it is correct for all wave lengths for infinitesimal waves, relevant wave groups are obtained consisting of constituent waves with a certain maximal wave length; other models for the dispersion (such as in the KdV-equation) lead to different results.

During asthma attacks, allergens activate sensitized basophils in the lung, thereby aggravating symptoms. Due to the paucity of basophils in bronchial lavage fluid and the lack of specific basophil detection and quantification methods, basophil-directed research in these samples was hampered in the past. This study aimed to establish and validate a flow cytometry-based basophil detection and quantification method for human basophils from bronchoalveolar lavage (BAL) and blood as a prerequisite for a better understanding of their pathogenic contribution and subtyping of asthma phenotypes. BAL and blood leukocytes from seasonal asthmatics were analyzed by flow cytometry. Chipcytometry, a highly sensitive single-cell analysis method, was used to validate the staining panel for basophils. Cell differentials of May-Grunwald-Giemsastained cytospins were used to compare basophil percentages. BAL basophils are identifiable as CD123(+)HLA-DR(-)CD3(-)CD14(-)CD19(-)CD20(-)CD56(-) cells in flow cytometrical analysis. Their identity was validated by Chipcytometry. CD203c was highly expressed by BAL basophils, whereas it was expressed at variable levels on blood basophils. The two quantification methods correlated, although more basophils were detected by flow cytometry. Furthermore, the increase in basophil percentages in the lung correlated with the decrease in the basophil percentages in the blood after allergen challenge. We here validated a reliable basophil quantification method, which is independent of the cell's activation and degranulation state. The results obtained with this method indicate that basophils are directly recruited from the blood circulation to the airway lumen.

On Tuesday 28th September 2010 the first Master excursion of the current academie year took place. With a group of roughly 25 people the B.I.L. visited the International Court of Justice (ICJ) which is situated in the Peace Palace in The Hague. During our visit we got the chance to sit down and talk with a representative of the Peace Palace. Afterwards a tour of the Peace Palace was offered to us.

Tijdens een lustrumjaar is het gebruikelijk om terug te kijken op het verleden. Wanneer we terugkijken op de historie van de opleiding Bestuurskunde, dan zijn er twee Europese steden van grote invloed geweest op deze studie: Rome en Athene. Voor het eerst in de B.I.L.-geschiedenis werd er tijdens een studiereis een bezoek gebracht aan deze twee steden. Op zaterdag 26 juni 201 O vertokken 22 enthousiaste B .I.L. 'ers naar Athene om vervolgens op 30 juni 2010 door te vliegen naar Rome.

2009-2010 wordt een belangrijk jaar voor de B.I.L. Ons zilveren Lustrum staat voor de boeg, wat gepaard zal gaan met een hoop festiviteiten. De grote vraag is wie ons gaat leiden gedurende dit Lustrumjaar. Het 24e heeft zich hierover gebogen en presenteert hierbij het 25e kandidaatsbestuur der B.I.L. Maak kennis met Marjoleine, Marjolein, Jessica, Lisanne, Johan, Daniël en Liesje ...

Depressie is één van ‘s werelds meest voorkomende psychische stoornissen. Cognitieve gedragstherapie (CGT) is aangetoond als effectief in het terugdringen van depressie. Probleem is echter dat er op dit moment te weinig therapeuten zijn om iedereen tijdig te kunnen behandelen. Gecomputeriseerde CGT zou een oplossing kunnen zijn voor dit probleem. In dit systematische overzicht zijn gerandomiseerde onderzoeken verzameld die de effectiviteit van computergeleverde CGT vergelijkt met de effectiviteit van therapeutgeleverde CGT bij het terugdringen van depressie. Daarnaast is aanvullend contact bij de gecomputeriseerde therapie geanalyseerd en onderzocht of de aard en hoeveelheid van het contact invloed heeft op de effectiviteit van gecomputeriseerde CGT. Uit vier van de vijf onderzoeken kwam naar voren dat computergeleverde CGT even effectief is als therapeutgeleverde CGT in het terugdringen van depressie. In één onderzoek werd geconcludeerd dat therapeutgeleverde therapie effectiever is dan computergeleverde therapie.