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s-Hertogenbosch, Netherlands

HAS University of Applied science is an independent university of applied science, specialising in agriculture, horticulture, food, nature conservation and environment. It is located in 's-Hertogenbosch, the regional capital of North Brabant, and accredited by the Dutch Flemish Accreditation Organisation. In 2013 there were around 2400 students enrolled at HAS University of Applied science. Wikipedia.


Winfield I.J.,UK Center for Ecology and Hydrology | van Rijn J.,HAS Den Bosch University of Applied Sciences | Valley R.D.,Navico Inc
Ecological Informatics | Year: 2015

Accurate information on the location and condition of spawning grounds of environmentally-demanding lithophilic fish species, which may use only a very small area of their habitat for spawning, is critical to their conservation and fisheries management but is frequently lacking. Here, the new hydroacoustic system BioBase, which enables the rapid characterisation of features including lake bottom hardness (with soft, medium hard and hard bottoms represented by values of 0 to 0.25, 0.25 to 0.40, and 0.40 to 0.50, respectively), was applied to known spawning grounds of Arctic charr (Salvelinus alpinus) in the north basin of the eutrophicated lake of Windermere, U.K. The output of BioBase was successfully ground-truthed using an independent video-based system (r2=0.48, F=17.705, p<0.001) and depth and bottom hardness descriptive statistics were produced for six spawning grounds. Average depth ranged from 9.4m (North Thompson Holme) to 38.5m (Balla Wray), while average bottom hardness ranged from 0.254 (Low Wray Bay) to 0.303 (North Thompson Holme). Detailed visual outputs were also produced for contrasting shallow (North Thompson Holme) and deep (Holbeck Point) spawning grounds, both of which showed high within-site spatial variation in bottom hardness and thus in suitability for spawning. Findings were consistent with earlier, less quantitative, interpretations of the possible effects of eutrophication and associated increased deposition of fine sediments on local Arctic charr reproduction. © 2015 Elsevier B.V. Source


de Cocq P.,Experimental Zoology Group | de Cocq P.,HAS Den Bosch University of Applied Sciences | Mariken Duncker A.,VU University Amsterdam | Clayton H.M.,Michigan State University | And 3 more authors.
Journal of Biomechanics | Year: 2010

In equestrian sports, it is generally assumed that rising and sitting trot load the horse's back differently. The objective of this study was to quantify the load on the horse's back in these riding techniques. Kinematic data of 13 riders were collected in rising and sitting trot. The time-history of the position of the rider's centre of mass (CoM) was calculated, and differentiated twice to obtain the acceleration of the CoM. The reaction force between the rider and the horse's back was calculated from the acceleration. Forces were divided by the body weight of the rider to obtain dimensionless forces. As expected, the computed average vertical force did not differ between riding techniques and was not significantly different from the body weight of the riders. At trot, two force peaks were present during one stride cycle. Both peaks in rising trot were significantly lower compared to sitting trot (peak 1: 2.54±0.30 versus 2.92±0.29; p<0.001; peak 2: 1.95±0.34 versus 3.03±0.32; p<0.001). This supports the general assumption that rising trot is less demanding for the horse than sitting trot. © 2009 Elsevier Ltd. Source


Sheppard L.J.,UK Center for Ecology and Hydrology | Leith I.D.,UK Center for Ecology and Hydrology | Leeson S.,UK Center for Ecology and Hydrology | Mizunuma T.,University of Edinburgh | And 3 more authors.
Biogeochemistry | Year: 2013

Wet N deposition comprises oxidised (nitrate) and reduced (ammonium) N forms in proportions that vary spatially with source and topography. Field evidence of long-term N form effects on semi-natural ecosystems and how these are modified by phosphorus and potassium availability are lacking. This study describes cover changes for some key peatland species and litter chemistry from Sphagnum capillifolium, Calluna and Eriophorum vaginatum, and peat in response to 9 years of N treatment. Ammonium and nitrate as NH4Cl or NaNO3 were provided to replicate plots in rainwater spray at +8 (low) or +56 (high) kg N ha-1 year, with and without PK via an automated system coupled to site meteorological conditions. Reduced N caused greater N accumulation in all key species than oxidised N, especially at higher doses, but cover declined more, though not significantly so, with oxidised than reduced N at the high N dose. Overall the detrimental effects of high N on Sphagnum and Calluna cover were significant but small. By comparison PK inclusion with 56 kg N ha-1 year as oxidised N, not reduced N, had devastating effects on cover, causing both S. capillifolium and Calluna to decrease 3-5-fold, facilitating invasion and expansion of nitrophiles, non-characteristic bog plants e.g. Epilobium angustifolium, Epilobium palustre, Juncus effusus, Digitalis purpurea and Dryopteris dilatata. N form appears to be significant for peatlands because of its effects on pH. The significance of changes in plant cover for peat chemistry and decomposition for biogeochemistry is discussed. © 2013 Springer Science+Business Media Dordrecht. Source


van Beek F.E.,Experimental Zoology Group | de Cocq P.,Experimental Zoology Group | de Cocq P.,HAS Den Bosch University of Applied Sciences | Timmerman M.,Dutch Equestrian Vocational Center | Muller M.,Experimental Zoology Group
Veterinary Journal | Year: 2012

Injuries of horses might be related to the force the rider exerts on the horse. To better understand the loading of the horse by a rider, a sensor was developed to measure the force exerted by the rider on the stirrups. In the study, five horses and 23 riders participated. Stirrup forces measured in sitting trot and rising trot were synchronised with rider movements measured from digital films and made dimensionless by dividing them by the bodyweight (BW) of the rider. A Fourier transform of the stirrup force data showed that the signals of both sitting and rising trot contained 2.4 and 4.8. Hz frequencies. In addition, 1.1 and 3.7. Hz frequencies were also present at rising trot. Each stride cycle of trot showed two peaks in stirrup force. The heights of these peaks were 1.17 ± 0.28 and 0.33 ± 0.14 in rising and 0.45 ± 0.24 and 0.38 ± 0.22 (stirrup force (N)/BW of rider (N)) in sitting trot. A significant difference was found between the higher peaks of sitting and rising trot (P< 0.001) and between the peaks within a single stride for both riding styles (P< 0.001). The higher peak in rising trot occurred during the standing phase of the stride cycle. Riders imposed more force on the stirrups during rising than sitting trot. A combination of stirrup and saddle force data can provide additional information on the total loading of the horse by a rider. © 2011 Elsevier Ltd. Source


Winfield I.J.,Lake Ecosystems Group | van Rijn J.,HAS Den Bosch University of Applied Sciences | Valley R.D.,Navico Inc. 1229 Tyler St. NE and 120
Ecological Informatics | Year: 2015

Accurate information on the location and condition of spawning grounds of environmentally-demanding lithophilic fish species, which may use only a very small area of their habitat for spawning, is critical to their conservation and fisheries management but is frequently lacking. Here, the new hydroacoustic system BioBase, which enables the rapid characterisation of features including lake bottom hardness (with soft, medium hard and hard bottoms represented by values of 0 to 0.25, 0.25 to 0.40, and 0.40 to 0.50, respectively), was applied to known spawning grounds of Arctic charr (Salvelinus alpinus) in the north basin of the eutrophicated lake of Windermere, U.K. The output of BioBase was successfully ground-truthed using an independent video-based system (r2 =0.48, F=17.705, p<0.001) and depth and bottom hardness descriptive statistics were produced for six spawning grounds. Average depth ranged from 9.4m (North Thompson Holme) to 38.5m (Balla Wray), while average bottom hardness ranged from 0.254 (Low Wray Bay) to 0.303 (North Thompson Holme). Detailed visual outputs were also produced for contrasting shallow (North Thompson Holme) and deep (Holbeck Point) spawning grounds, both of which showed high within-site spatial variation in bottom hardness and thus in suitability for spawning. Findings were consistent with earlier, less quantitative, interpretations of the possible effects of eutrophication and associated increased deposition of fine sediments on local Arctic charr reproduction. © 2015 Elsevier B.V. Source

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