Spasticity reduction using electrical stimulation in the lower limb of spinal cord injury patients

The goal of the thesis was to study the effect of electrical stimulation in SCI patients to reduce spasticity in muscles of the leg and to improve gait performance, using both the carryover and the instant effect. To achieve this goal it was necessary to have appropriate spasticity measures for the carry-over effect and the instant effect, thus during rest and gait. Using these measures, we studied the carryover and the instant effect of electrical stimulation on spasticity

Adapting to a changing highschool population

This paper reports the recent changes in the EE Bachelor program at the University of Twente. Recent generations of freshman students exhibited a lack in mathematics skills and the ability to grasp the physics behind the equations. By starting of the curriculum with a new course “Introduction to electronics and electrical engineering (IEEE)�? we have managed to solve the issue of lacking entry levels while simultaneously eliminating the unmotivated or under skilled students in a very early stage in their studies

An Alternate Method for Fourier Transform Infrared (FTIR) Spectroscopic Determination of Soil Nitrate Using Derivative Analysis and Sample Treatments

This study aimed at examining effective sample treatments and spectral processing for an alternate method of soil nitrate determination using the attenuated total reflectance (ATR) of Fourier transform infrared (FTIR) spectroscopy. Prior to FTIR measurements, soil samples were prepared as paste to enhance adhesion between the ATR crystal and sample. The similar nitrate peak heights of soil pastes and their supernatants indicated that the nitrate in the liquid portion of the soil paste mainly responded to the FTIR signal. Using a 0.01-M CaSO4 solution for the soil paste, which has no interference bands in the characteristic spectra of the analyte, increased the concentration of the nitrates to be measured. Second-order derivatives were used in the prediction model to minimize the interference effects and enhance the performance. The second-order derivative spectra contained a unique nitrate peak in a range of 1,400-1,200 cm(-1) without interference of carbonate. A partial least square regression model using second-order derivative spectra performed well (R (2) = 0.995, root mean square error (RMSE) = 23.5, ratio of prediction to deviation (RPD) = 13.8) on laboratory samples. Prediction results were also good for a test set of agricultural field soils with a CaCO3 concentration of 6% to 8% (R (2) = 0.97, RMSE = 18.6, RPD = 3.5). Application of the prediction model based on soil paste samples to nitrate stock solution resulted in an increased RMSE (62.3); however, validation measures were still satisfactory (R (2) = 0.99, RPD = 3.0

Nutrient loss pathways from grazed grasslands and the effects of decreasing inputs: experimental results for three soil types

Agriculture is a main contributor of diffuse emissions of N and P to the environment. For N the main loss pathways are NH3-volatilization, leaching to ground and surface water and N-2(O) emissions. Currently, imposing restraints on farm inputs are used as policy tool to decrease N and P leaching to ground water and to surface water, and the same measure is suggested to combat emissions of N2O. The response, however, to these measures largely depends on the soil type. In this study nutrient flows of three dairy farms in The Netherlands with comparable intensity on sand, peat and clay soils were monitored for at least 2 years. The first aim was to provide quantitative data on current nutrient loss pathways. The second aim was to explore the responses in partitioning of the nutrient loss pathways when farm inputs were altered. Mean denitrification rates ranged from 103 kg N ha(-1) year(-1) for the sandy soil to 170 kg N ha(-1) year(-1) for the peat soil and leaching to surface water was about 73 kg N ha(-1) year(-1) for the sandy soil, 15 kg N ha(-1) year(-1) for the clay soil and 38 kg N ha(-1) year(-1) for the peat soil. For P, leaching to surface water ranged from 2 kg P ha(-1) year(-1) for the sandy site to 5 kg P ha(-1) year(-1) for the peat site. The sandy soil was most responsive to changes in N surpluses on leaching to surface water, followed by the peat soil and least responsive was the clay soil. For P, a similar sequence was found. This article demonstrates that similar reductions of N and P inputs result in different responses in N and P loss pathways for different soil types. These differences should be taken into account when evaluating measures to improve environmental performance of (dairy) farm

PLEASE: een instrument om de fosfaatlekkage van een perceel naar het oppervlaktewater vast te stellen

PLEASE (Phosphorus LEAching from Soils to the Environment) berekent de fosfaatvracht van een perceel naar de perceelsloot op basis van het verloop van de fosfaatconcentratie in de bodem en de waterafvoer over het perceel en uit de verschillende bodemlagen van het perceel naar het oppervlaktewater. PLEASE is het afgelopen jaar getoetst op 14 Nederlandse en 17 Deense locaties (Dupas en van der Salm, 2010; van der Salm et al.,2011). Op deze 31 locaties waren metingen beschikbaar van de fosforfluxen naar het oppervlaktewater of van concentraties in het grondwater, de drains of het bodemvocht voor een periode van enkele jaren. De Deense locaties zijn goed vergelijkbaar met de Nederlandse percelen, maar hebben gemiddeld genomen een iets lagere fosfaattoestand in de ondergrond en zijn wat dieper gedraineer

Langetermijneffecten van verminderde fosfaatgiften

Het huidige fosfaatbeleid richt zich op het verminderen van de fosfaatgiften om zodoende de fosfaatophoping in de bodem te stoppen en de verliezen van fosfaat naar het oppervlaktewater te verlagen. In deze studie wordt ingegaan op de mogelijkheid om de effecten van verminderde fosfaatgift op bodemvruchtbaarheid en uitspoeling te voorspellen. Om dit doel te bereiken, zijn gegevens van bestaande proeven verzameld en is het gedrag van fosfaat gesimuleerd op basis van de concepten die in het nutrientenemissiemodel STONE worden gehanteerd. Uit het onderzoek blijkt dat bij een juiste instelling van de desorptieparameters het gedrag van fosfaat goed kan worden gesimuleerd. Het instellen van de juiste waarde voor de desoptieparameters is echter complex omdat: de desorptiesnelheid afhangt van de mate van oplading van de grond en desorptiesnelheden in het veld lager zijn dan onder laboratoriumcondities wordt vastgesteld

Time Thinking and Drawing in Designing Dynamic River Landscapes

This visual essay explores the use of time thinking and drawing in the design process of the Ooijen- Wanssum floodplain widening project. Through a series of project sketches, final drawings and photos of the constructed project, the authors reveal the way in which time drawing has (often implicitly) given direction to the design process. The water calendar is introduced as a design tool that integrates time- dependent river dynamics into the design process and thereby informs spatial design choices that are considered in several design sketches. These design choices include interactions with dynamic processes such as erosion, vegetation dynamics and recreational use of the river landscape

Dertien jaar fosfaatevenwichtsbemesting op graslandproeven: opbrengst en fosforgehalte van gras dalen

In 1997 hebben ASG en Alterra een veldproef opgestart met fosfaatevenwichtsbemesting op grasland. Het doel van deze veldproef is om na te gaan wat de gevolgen zijn van fosfaatevenwichtsbemesting voor kwaliteit en opbrengst van het gras. Het jaar 2009 was het 13e jaar van deze proef. De gegevens van 1997 tot en met 2009 zijn statistisch bewerkt en geanalyseerd

Introduction of ROL genes in Rosa hybrida L. for improved rootstock performance

In contrast to many other cut flowers, which are harvested completely at the time of flowering, rose plants ( Rosahybrida L.) continuously produce flowering shoots, which are harvested on a regular basis. For the release of axillary buds and development of flowering shoots high energy inputs are required in rose culture. However, for enviromnental reasons the use of fossil fuels should be limited i.e. the energy efficiency of rose production needs to be improved. The energy efficiency in horticulture was already remarkably improved by technical and cultural measures, which has been evolved since the energy crisis in the seventies. Breeding of roses, which produce more efficiently per unit energy input, is another powerful tool to save energy. The aim of the research described in this thesis is to genetically change roses in such a way that they can be cultured at low energy input.The production of flowering stems of roses is dependent on the number of axillary shoots or basal shoots. Axillary bud release is a plant developmental process, which is controlled by plant hormones, such as auxin and cytokinin. Auxin is produced in the apex and leaves of growing plants and is transported to the roots, while cytokinin is produced in the root tips and transported to the aerial parts. This means that the hormonal status of the roots influences the development of the whole plant. Many cut roses are therefore grafted on a rose rootstock; not only to enhance axillary bud release and flower production, but also to overcome deficiencies in adventitious root formation. The separation of rose plants in a scion and a rootstock part gives opportunity to specific breeding programmes for flower and root characteristics. In contrast to a high breeding activity in cut roses, breeding efforts for rose rootstocks have been relatively poor. This opens perspectives for the development of new rose rootstocks, either via cross breeding or more recently also via genetic modification. The latter approach has the advantage that gene transfer is no longer determined by crossing potential, but principally unlimited from one species to another species. In this thesis we aimed at the improvement of rootstock performance by the introduction of the ROL genes from the bacterium Agrobacterium rhizogenes. These genes influence plant development by interference in hormone metabolism or hormone sensitivity.A prerequisite for genetic modification is the availability of reliable transformation procedures. At the start of this research such a transformation protocol was not available for rose. Since rose is a recalcitrant species in this respect, much attention has been paid to the development of methodological principles of genetic modification, such as micropropagation, transformation and regeneration.First, the micropropagation of the rose rootstock 'Moneyway' was examined. On standard media either shoot growth was inadequate or leaves became chlorotic, suggesting an iron deficiency. Replacement of FeEDTA by the more stable iron chelate FeEDDHA in the medium resulted in the development of green shoots for more than three months.Adventitious root formation of rose was studied on stem slices of micropropagated shoots. First it was shown that the formation of adventitious roots was dependent on the auxin dose and was not affected by the presence of other root primordia on the same stem slice. Secondly, to study the effects of ROL genes, a method was developed for the production of transformed roots, using 5 mg/L kanamycin for selection. Kanamycin resistant roots were formed on stem slices, which were inoculated with A.rhizogenes, harbouring the complete Ri plasmid encompassing the ROL genes and a binary plasmid with the neomycin phosphotransferase ( NPTII ) gene for kanamycin resistance. In contrast to adventitious root formation, the formation of these Ri transformed roots was independent of the presence of auxin. This autonomous formation of Ri roots might be due to the transfer of AUX genes, which offer an alternative synthesis route for auxin. Stem slices, inoculated with A . tumefaciens harbouring only the NPTII gene, formed on kanamycin containing medium with high auxin concentrations first callus and subsequently roots. The formation of such kanamycin resistant roots was significantly improved upon transformation with the ROLB gene under the strong CaMV 35S promoter and even more by transformation with a combination of ROLA, B, C genes. These experiments demonstrated that the ROLB gene and especially the ROLA, B, C genes are in principle suitable genes for improvement of the rooting ability of rose rootstocks.For the production of transformed rose plants a study was undertaken to establish a regeneration procedure. Plants were regenerated from excised adventitious roots via somatic embryogenesis. First, the roots were incubated on callus induction medium containing a high concentration of auxin (50 μ M 2,4-D). For embryo induction calluses were transferred to hormone-free medium. The use of Gelrite instead of agar during callus induction andlor embryo induction stimulated embryogenesis; up to 16% of the calluses formed organized structures. Approximately 40% of these structures further developed into shoots. Despite the long lasting callus phase during regeneration, the majority of the regenerant plants did not show any signs of somaclonal variation, indicating that we developed a suitable regeneration procedure.This regeneration procedure was applied for the regeneration of plants from excised kanamycin resistant roots. For this purpose first hundreds of kanamycin resistant roots were produced, with an efficiency of up to two roots per stem slice. Regeneration of plants from these roots lasted up to 12 months, but finally nine independent transformants were produced: four transformants with the reporter gene 35SGUSINT , one transformant with the ROLB gene behind its own promoter (B1) and four transformants with a combination of ROLA, B, C genes also driven by their own promoters (ABC1 to ABC4). Rooting experiments in vitro showed that adventitious root formation on shoots and leaves was enhanced by the presence of these ROL genes. Even in the absence of exogenous auxin roots were induced, probably due to an increased sensitivity for endogenous auxin. The presence of the ROLA, B, C genes also enhanced adventitious root formation on stem slices of micropropagated plants, whereas the ROLB gene surprisingly decreased it. We suggested that this might be due to overexpression of the ROLB gene. The rooting experiments in vitro were confirmed by rooting experiments with cuttings from greenhouse grown plants; adventitious root formation was improved threefold upon introduction of the ROLB gene or a combination of ROLA, B, C genes.Next to an increased rooting ability of ROL gene transformed plants, many pleiotropic effects were observed in the greenhouse: increased (ROLB) or decreased ( ROLA,B, C) apical dominance, reduced plant weight and altered leaf morphology. Northern analysis showed that altered leaf shapes were correlated with the presence of specific ROL transcripts; wrinkled leaves with a ROLA messenger of 650 nt, round-edged leaves with a ROLB messenger of 1050 nt and small and lanceolate leaves with a ROLC messenger of 850 nt.The ROLB transformant (B1) and one ROLA, B, C transformant (ABC1) were used as rootstocks in combination plants with the cut rose cultivar Madelon as a scion. Growth and development were followed on hydroculture at two temperatures during three months. Although the formation of adventitious roots was initially enhanced by the ROLB gene, further root development was inhibited. Despite the smaller root system, the performance of the untransformed scion was as in the control. In contrast, root development was enhanced by the presence of ROLA, B, C genes, while the development of the untransformed aerial part was also affected. Regarding the aim of this research, the most important observation was that the release of axillary buds was increased from 0.1 to 0.6 and from 0.3 to 1.3 basal shoot per plants at 15 and 20°C, respectively. This enhanced axillary bud release might reflect either an increased production of cytokinin in such well developed root systems or a cytokinin-like action as mentioned for ROLC transformed plants. In this respect it should be mentioned that the ROLC gene was indeed active in ROLA, B, C transformed roots. Since the formation of these basal shoots is correlated with flower production, we expect that application of ROLA, B, C transformed rootstocks will lead to a more energy efficient flower production both at 20°C and 15°C.In the final part of this thesis, prospects for the applications of ROL genes for crop improvement are discussed. As suggested in many reports, the ROL genes are principally suitable tools to modify plant developmental processes such as adventitious root formation and axillary bud release. However, practical application of ROL gene transformed plants might be hampered by the many pleiotropic side effects, as observed in completely transformed roses. Based on the research described in this thesis, we offer a novel approach for application, which is clearly different from earlier strategies. It was demonstrated for the first time that expression of ROL genes in the rootstock led to a beneficial stimulation of axillary bud release of the untransformed scion, without the transmissibility of many undesired pleiotropic effects