Polynomial normal forms of Constrained Differential Equations with three parameters

We study generic constrained differential equations (CDEs) with three parameters, thereby extending Takens's classification of singularities of such equations. In this approach, the singularities analyzed are the Swallowtail, the Hyperbolic, and the Elliptic Umbilics. We provide polynomial local normal forms of CDEs under topological equivalence. Generic CDEs are important in the study of slow-fast (SF) systems. Many properties and the characteristic behavior of the solutions of SF systems can be inferred from the corresponding CDE. Therefore, the results of this paper show a first approximation of the flow of generic SF systems with three slow variables.Comment: This is an updated and revised version. Minor modifications mad

Inclination Measurement of Human Movement Using a 3-D Accelerometer With Autocalibration

In the medical field, accelerometers are often used for measuring inclination of body segments and activity of daily living (ADL) because they are small and require little power. A drawback of using accelerometers is the poor quality of inclination estimate for movements with large accelerations. This paper describes the design and performance of a Kalman filter to estimate inclination from the signals of a triaxial accelerometer. This design is based on assumptions concerning the frequency content of the acceleration of the movement that is measured, the knowledge that the magnitude of the gravity is 1 g and taking into account a fluctuating sensor offset. It is shown that for measuring trunk and pelvis inclination during the functional three-dimensional activity of stacking crates, the inclination error that is made is approximately 2/spl deg/ root-mean square. This is nearly twice as accurate as compared to current methods based on low-pass filtering of accelerometer signals

The Influence of Accelerated Reader on the Affective Literacy Orientations of Intermediate Grade Students

Although the highly popular Accelerated Reader (AR) book reading incentive program claims to motivate children of all reading ability levels, very little independent empirical research has examined this assertion. To help fill this void, we used two related three-factor mixed designs with Method (AR vs. Control), Gender, and either Grade Level(fourth vs. fifth) or Reading Ability (high vs. low) to explore AR’s influence on the reading attitudes and self-perceptions of children in two comparable school districts. The analyses indicate that AR positively influenced academic reading attitudes, but not recreational ones, and that it negatively influenced two types of self-perceptions in low achieving male readers. These findings and others of consequence are discussed along with implications for future research

Estimation of hand and finger kinematics using inertial sensors

A new dataglove is developed and presented. Inertial sensors are placed on various hand and finger segments to estimate the hand pose

Compensation of Magnetic Disturbances Improves Inertial and Magnetic Sensing of Human Body Segment Orientation

This paper describes a complementary Kalman filter design to estimate orientation of human body segments by fusing gyroscope, accelerometer, and magnetometer signals from miniature sensors. Ferromagnetic materials or other magnetic fields near the sensor module disturb the local earth magnetic field and, therefore, the orientation estimation, which impedes many (ambulatory) applications. In the filter, the gyroscope bias error, orientation error, and magnetic disturbance error are estimated. The filter was tested under quasi-static and dynamic conditions with ferromagnetic materials close to the sensor module. The quasi-static experiments implied static positions and rotations around the three axes. In the dynamic experiments, three-dimensional rotations were performed near a metal tool case. The orientation estimated by the filter was compared with the orientation obtained with an optical reference system Vicon. Results show accurate and drift-free orientation estimates. The compensation results in a significant difference (p<0.01) between the orientation estimates with compensation of magnetic disturbances in comparison to no compensation or only gyroscopes. The average static error was 1.4/spl deg/ (standard deviation 0.4) in the magnetically disturbed experiments. The dynamic error was 2.6/spl deg/ root means square

What Matters Most? A Survey of Accomplished Middle-Level Educators\u27 Beliefs and Values about Literacy

Ninety teachers working in award-winning middle schools responded to a survey that explored, quantitatively and qualitatively, how they (1) defined themselves as teachers of literacy, (2) viewed multiliteracies in adolescents\u27 lives, and (3) valued these literacies in the classroom. Mean scores indicated that Basic Literacies (e.g., comprehension, word identification, fluency, writing) were rated more favorably than New Literacies (e.g., media, Internet, critical, out of school). Strong qualitative support existed for literacy instruction in all disciplines, but interpretations varied. The most positive agreement centered on every teacher being a teacher of literacy. Little support existed for developing students\u27 out-of-school literacies in schools. Such findings have strong implications for altering curricular emphases and merging teacher practice with adolescents\u27 needs and interests

Glucocorticoid Receptor Variants Modulate the Sensitivity to Cortisol

Synthetic glucocorticoids are used therapeutically for numerous indications. However, due to their broad physiological effects across many systems, side effects of GC therapy can be extensive and limit the clinical utility of GCs as a drug. One of the main urgent questions at this moment is to develop insights into the cause of the differences in the response between individuals to therapeutically applied GCs. Some patients respond to low doses, with or without side effects, while others do not respond at all. This thesis discusses a number of possible explanations for these differences in GC sensitivity and is focused on genetic, but also on transcriptional and translational aspects of the GR gene. Furthermore, it is also described how glucocorticoid sensitivity disorders can be characterized clinically and biochemically. An important tool in these studies has been a newly developed bioassay, measuring cellular GC sensitivity ex vivo, based on GR action at the transcriptional level by studying GC-regulated mRNA expression (chapter 2). Various polymorphism in the GR gene (N363S, ER22/23EK, and 9beta) are shown to affect GC sensitivity in vivo and in/ex vitro and result in a wide variety of phenotypic signs (chapters 3, 4, and 5). Furthermore, studies described in chapter 4, 5, 6, and 7 have demonstrated that also transcriptional and translational variants of the GR and the use of different promoters could modulate GC sensitivity. These factors modulating inter- individual sensitivity to GCs may have consequences for the use of GCs in a clinical setting. When treating patients with GCs, they need an individually determined optimal dose to obtain a balance between beneficial and adverse effects

Tunable chiral spin texture in magnetic domain-walls

Magnetic domain-walls (DWs) with a preferred chirality exhibit very efficient current-driven motion. Since structural inversion asymmetry (SIA) is required for their stability, the observation of chiral domain walls in highly symmetric Pt/Co/Pt is intriguing. Here, we tune the layer asymmetry in this system and observe, by current-assisted DW depinning experiments, a small chiral field which sensitively changes. Moreover, we convincingly link the observed efficiency of DW motion to the DW texture, using DW resistance as a direct probe for the internal orientation of the DW under the influence of in-plane fields. The very delicate effect of capping layer thickness on the chiral field allows for its accurate control, which is important in designing novel materials for optimal spin-orbit-torque-driven DW motion.Comment: 12 pages, 5 figure

You Are What You Eat: Mass spectrometry in paediatric kinetic studies using stable isotopes

An overview will be presented about applications of stable isotopes in paediatric research. Mass spectrometry has proven to be an essential tool for unravelling kinetic studies in a large range of different research disciplines related to intestinal diseases, obesities, severe cerebral palsy, oxidative stress and foetal metabolism. Due to the diversity and complexity of the different metabolites involved in these studies, there is a high demand on sophisticated mass spectrometric instruments. Several new methods have been developed for measurement of isotopic labelled compounds in body fluids. 13C isotopic glucose enrichment in human plasma is analysed, using liquid chromatography isotope ratio mass spectrometry (LC/IRMS). Also new methods were developed for measuring the glutathione (GSH) fractional synthesis rate (FSR) in neonates after infusion of [1-13C]glycine as a tracer. For measuring energy expenditure and total body water composition in humans the doubly labelled water method is valuable technique. It usually involves blood or urine sampling, which might be difficult in neonates and children with cerebral palsy or other disabilities. We therefore aimed to validate a method making use of saliva samples analyzed by automated thermal conversion elemental analyzer in combination with isotope ratio mass spectrometry (TC/EA/IRMS). The different types of mass spectrometric instruments will be discussed here as well as several applications in paediatric research utilizing these techniques. The applications cover amino acid metabolism and body composition, energy expenditure, and the synthesis of specific proteins such as glutathione and albumin in different groups of children and even in foetuses. Finally, the aims and outline of this dissertation are covered