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Controlling tsetse flies is critical for effective management of African trypanosomiasis in Sub-Saharan Africa. To enhance timely and targeted deployment of tsetse control strategies a better understanding of their temporal dynamics is paramount. A few empirical studies have explained and predicted tsetse numbers across space and time, but the resulting models may not easily scale to other areas. We used tsetse catches from 160 traps monitored between 2017 and 2019 around Shimba Hills National Reserve in Kenya, a known tsetse and trypanosomiasis hotspot. Traps were divided into two groups: proximal ( 1.0 km) from the outer edge of the reserve boundary. We fitted zero-inflated Poisson and generalized linear regression models for each group using as temporal predictors rainfall, NDVI (Normalized Difference Vegetation Index), and LST (land surface temperature). For each predictor, we assessed their relationship with tsetse abundance using time lags from 10 days up to 60 days before the last tsetse collection date of each trap. Tsetse numbers decreased as distance from the outside of reserve increased. Proximity to croplands, grasslands, woodlands, and the reserve boundary were the key predictors for proximal traps. Tsetse numbers rose after a month of increased rainfall and the following increase in NDVI values but started to decline if the rains persisted beyond a month for distant traps. Specifically, tsetse flies were more abundant in areas with NDVI values greater than 0.7 for the distant group. The study suggests that tsetse control efforts beyond 1.0 km of the reserve boundary should be implemented after a month of increased rains in areas having NDVI values greater than 0.7. To manage tsetse flies effectively within a 1.0 km radius of the reserve boundary, continuous measures such as establishing an insecticide-treated trap or target barrier around the reserve boundary are needed.

Patients with Alzheimer’s disease (AD) often have fragmentation of sleep/wake cycles and disrupted 24-h (circadian) activity. Despite this, little work has investigated the potential underlying day/night disruptions in cognition and neuronal physiology in the hippocampus. The molecular clock, an intrinsic transcription-translation feedback loop that regulates circadian behavior, may also regulate hippocampal neurophysiological activity. We hypothesized that disrupted diurnal variation in clock gene expression in the hippocampus corresponds with loss of normal day/night differences in membrane excitability, synaptic physiology, and cognition. We previously reported that the Tg-SwDI mouse model of AD has disrupted circadian locomotor rhythms and neurophysiological output of the suprachiasmatic nucleus (the primary circadian clock). Here, we report that Tg-SwDI mice failed to show day-night differences in a spatial working memory task, unlike wild-type controls that exhibited enhanced spatial working memory at night. Moreover, Tg-SwDI mice had lower levels of Per2, one of the core components of the molecular clock, at both mRNA and protein levels when compared to age-matched controls. Interestingly, we discovered neurophysiological impairments in area CA1 of the Tg-SwDI hippocampus. In controls, spontaneous inhibitory post-synaptic currents (sIPSCs) in pyramidal cells showed greater amplitude and lower inter-event interval during the day than the night. However, the normal day/night differences in sIPSCs were absent (amplitude) or reversed (inter-event interval) in pyramidal cells from Tg-SwDI mice. In control mice, current injection into CA1 pyramidal cells produced more firing during the night than during the day, but no day/night difference in excitability was observed in Tg-SwDI mice. The normal day/night difference in excitability in controls was blocked by GABA receptor inhibition. Together, these results demonstrate that the normal diurnal regulation of inhibitory transmission in the hippocampus is diminished in a mouse model of AD, leading to decreased daytime inhibition onto hippocampal CA1 pyramidal cells. Uncovering disrupted day/night differences in circadian gene regulation, hippocampal physiology, and memory in AD mouse models may provide insight into possible chronotherapeutic strategies to ameliorate Alzheimer’s disease symptoms or delay pathological onset.

Although cultural diversity of students is inspiring, teachers need to consider the variation in educational and cultural backgrounds as well as the different characters of the students. One strategy can be the application of student-centred learning. However, this may affect students that have been accustomed to different teaching strategies. Therefore, the objective of this paper is to assess the appreciation of international students for different teaching methods. A survey and a workshop were held to ask students for their experiences with different teaching methods before coming to ITC, their appreciation of student-centred learning, and to determine personal character traits. We found that differences between nationalities were rather small, although there were some suggestions that there are differences in attitude between individuals from different continents. The workshop revealed that teachers should better explain and justify their teaching methods as students do not always understand the reason why certain teaching methods are chosen. Besides, with a mixed group of cultures, teachers must stay aware that students sometimes prefer to give polite rather than honest indications on their learning.

Amyloid-beta (Abeta) has remained a central feature in research into Alzheimer's disease (AD). Yet the function of the amyloid-beta protein precursor (AbetaPP) and its processing products in the central nervous system is controversial. This review examines experimental literature from cell cultures to transgenic AD and brain injury models with a special emphasis on the functional role of AbetaPP and AbetaPP-derived peptides. AbetaPP knock-out mice exhibit severe metabolic abnormalities and behavioral deficits, indicating an important physiological function of AbetaPP. Also, an increasing body of evidence suggests that while Abeta is undoubtedly linked to neurodegeneration, the soluble amino-terminal fragment of AbetaPP (sAbetaPPalpha) has neuroprotective, neurotrophic, and cell adhesive functions. Moderate overexpression of human AbetaPP in rodents does not produce apparent Abeta pathology and has no significant effect on cognitive or sensorimotor behavior and, surprisingly, may even provide histological neuroprotection against focal cerebral ischemia. In contrast, phenotypes with more severe Abeta pathology show impaired cognitive performance, increased vulnerability to brain ischemia and trauma, and less favorable functional outcome even before Abeta deposition. A delicate balance in AbetaPP processing seems to determine its functional consequences. Thus, it is tempting to speculate that promotion of alpha-secretase-mediated cleavage of AbetaPP, which leads to increased sAbetaPPalpha production, provides a novel therapeutic strategy in the treatment of AD and brain injury.

In dit rapport wordt een toelichting gegeven op het spoorgoederenvervoer dat via de Nederlands-Duitse grensovergangen wordt vervoerd. Hierbij wordt gekeken naar de omvang (hoeveelheid goederenvervoer) en aard (type goederenvervoer) van dit vervoer naar herkomsten en bestemmingen (regio’s) voor het basisjaar 2007 en naar de verwachte ontwikkelingen van het spoorgoederenvervoer voor het toekomstjaar 2020

TNO heeft in het kader van het onderzoeksprogramma Kennis voor Klimaat in een consortium met het Havenbedrijf Rotterdam, DVS, Deltares, TU Delft, de VU en Arcadis onderzocht wat de impact is van klimaatverandering op de concurrentiepositie van de binnenvaart. Eerst hebben wij de impact inzichtelijk gemaakt en vervolgens een analyse gedaan. In deze analyse staan mogelijke logistieke maatregelen beschreven om de problemen als gevolg van met name lage waterstanden te verminderen of op te lossen. Hierbij gaat het zowel om maatregelen gericht op incidentele problemen als om structurele problemen. Voor de binnenvaart betekenen lage waterstanden dat alleen nog gevaren kan worden als de schepen deels beladen worden waardoor ze minder diep steken of in de meer extreme gevallen dat er helemaal niet meer gevaren kan worden. Als gevolg hiervan stijgen de transportkosten van de binnenvaart en neemt de betrouwbaarheid van de binnenvaart af. In een aanvullende analyse heeft TNO bepaald wat de impact hiervan is op de concurrentiepositie van de binnenvaart.