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PKAN, CoPAN, MePAN, and PDH‐E2 deficiency share key phenotypic features but harbor defects in distinct metabolic processes. Selective damage to the globus pallidus occurs in these genetic neurodegenerative diseases, which arise from defects in CoA biosynthesis (PKAN, CoPAN), protein lipoylation (MePAN), and pyruvate dehydrogenase activity (PDH‐E2 deficiency). Overlap of their clinical features suggests a common molecular etiology, the identification of which is required to understand their pathophysiology and design treatment strategies. We provide evidence that CoA‐dependent activation of mitochondrial acyl carrier protein (mtACP) is a possible process linking these diseases through its effect on PDH activity. CoA is the source for the 4′‐phosphopantetheine moiety required for the posttranslational 4′‐phosphopantetheinylation needed to activate specific proteins. We show that impaired CoA homeostasis leads to decreased 4′‐phosphopantetheinylation of mtACP. This results in a decrease of the active form of mtACP, and in turn a decrease in lipoylation with reduced activity of lipoylated proteins, including PDH. Defects in the steps of a linked CoA‐mtACP‐PDH pathway cause similar phenotypic abnormalities. By chemically and genetically re‐activating PDH, these phenotypes can be rescued, suggesting possible treatment strategies for these diseases.

Inverse dynamic analysis using musculoskeletal modeling is a powerful tool, which is utilized in a range of applications to estimate forces in ligaments, muscles, and joints, non-invasively. To date, the conventional input used in this analysis is derived from optical motion capture (OMC) and force plate (FP) systems, which restrict the application of musculoskeletal models to gait laboratories. To address this problem, we propose a musculoskeletal model, capable of estimating the internal forces based solely on inertial motion capture (IMC) input and a ground reaction force and moment (GRF&M) prediction method. We validated the joint angle and kinetic estimates of the lower limbs against an equally constructed musculoskeletal model driven by OMC and FP system. The sagittal plane joint angles of ankle, knee, and hip presented excellent Pearson correlations (\rho = 0.95, 0.99, and 0.99, respectively) and root-mean-squared differences (RMSD) of 4.1 $\pm$ 1.3$\circ$, 4.4 $\pm$ 2.0$\circ$, and 5.7 $\pm$ 2.1$\circ$, respectively. The GRF&M predicted using IMC input were found to have excellent correlations for three components (vertical:\rho = 0.97, RMSD=9.3 $\pm$ 3.0 %BW, anteroposterior: \rho = 0.91, RMSD=5.5 $\pm$ 1.2 %BW, sagittal: \rho = 0.91, RMSD=1.6 $\pm$ 0.6 %BW*BH), and strong correlations for mediolateral (\rho = 0.80, RMSD=2.1 $\pm$ 0.6%BW ) and transverse (\rho = 0.82, RMSD=0.2 $\pm$ 0.1 %BW*BH). The proposed IMC-based method removes the complexity and space-restrictions of OMC and FP systems and could enable applications of musculoskeletal models in either monitoring patients during their daily lives or in wider clinical practice., Comment: 19 pages, 4 figures, 3 tables

In veel land- en tuinbouwgewassen worden fungiciden ingezet om schimmels te bestrijden. Sinds 1970 is het meerdere malen voorgekomen dat schimmels resistentie opgebouwd hebben tegen fungiciden, die daardoor hun effectiviteit verliezen. 10 korte bijdragen van diverse onderzoekers.

In veel land- en tuinbouwgewassen worden fungiciden ingezet om schimmels te bestrijden. Sinds 1970 is het meerdere malen voorgekomen dat schimmels resistentie opgebouwd hebben tegen fungiciden, die daardoor hun effectiviteit verliezen. 10 korte bijdragen van diverse onderzoekers.

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

Dynamic interaction between the human body and the environment can be assessed by measuring force and estimating velocity at their interface. A sensorized glove with movement and force sensing is developed in which this principles is applied

Inertial and magnetic sensors, attached to various segments of the human hand, can be used to measure movements of the hand. This paper proposes a new method to assess hand kinematics by applying an Extended Kalman Filter in which prior information of the hand is fused with actual measurements obtained from various sensors.

The objective of the recently started EU project INTERACTION is to develop an unobtrusive and modular system for monitoring the quality of daily-life activities of stroke subjects involving the upper and lower limbs.

The external knee adduction moment (KAdM) during gait is an important parameter in patients with knee osteoarthritis (OA). KAdM measurement is currently restricted to instruments only available in gait laboratories. However, ambulatory movement analysis technology, including instrumented force shoes (IFS) and inertial and magnetic measurement systems (IMMS), can measure kinetics and kinematics of human gait free of laboratory restrictions.The objective of this study was a quantitative validation of the accuracy of the KAdM in patients with knee OA, when estimated with an ambulatory-based method (AmbBM) versus a laboratory-based method (LabBM). AmbBM is employing the IFS and a linked-segment model, while LabBM is based on a force plate and optoelectronic marker system. Effects of ground reaction force (GRF), centre of pressure (CoP), and knee joint position measurement are evaluated separately. Twenty patients with knee OA were measured.The GRFs showed differences up to 0.22. N/kg, the CoPs showed differences up to 4. mm, and the medio-lateral and vertical knee position showed differences to 9. mm, between AmbBM and LabBM. The GRF caused an under-estimation in KAdM in early stance. However, this effect was counteracted by differences in CoP and joint position, resulting in a net 5% over-estimation. In midstance and late stance the accuracy of the KAdM was mainly limited by use of the linked-segment model for joint position estimation, resulting in an under-estimation (midstance 6% and late stance 22%). Further improvements are needed in the estimation of joint position from segment orientation. © 2011 Elsevier Ltd.

This paper presents a method to estimate power transfer between the human body and the environment during short interactions and relatively arbitrary movements with net displacement and varying loads (mass and spring), and appeared to be accurate within 4%.

Traditionally, human body movement analysis is done in socalled ‘gait laboratories’, equipped with several measurement systems such as optical position measurement systems, EMG or force plates. The measured signals are used to estimate important gait variables. An important variable is the center of mass, an imaginary point at which the total body mass can be assumed to be concentrated. Several methods exist for center of mass estimation, of which the segmental kinematics method and the double integration of ground reaction force method are the most important ones. Other important variables are joint moment and powers. These can be estimated from estimations of body movement and ground reaction forces by applying inverse dynamics methods. A major drawback of the existing systems is the restriction to the laboratory environment. Therefore research is required for the development of measurement systems to perform these measurements in an ambulatory environment. The objective of this study is to give an overview of the possibilities of the forceshoe. The forceshoe is an ambulatory measurement system able to measure the ground reaction force and movement of foot and ankle.

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Center of Mass (CoM) displacement, an important variable to characterize human walking, was estimated in this study using an ambulatory measurement system. The ambulatory system was compared to an optical reference system. Root-mean-square differences between the magnitudes of the CoM appeared to be comparable to those described in literature.

INTRODUCTION Traditionally, human body movement analysis is done in so-called ‘gait laboratories’. In these laboratories, body movement is measured by a camera system using optical markers, the ground reaction force by a force plate fixed in the floor, and the muscle activity by EMG. From the body movements and ground reaction forces, joint moments and powers can be estimated by applying inverse dynamics methods. However, the main drawback is the restriction to the laboratory environment. In order to overcome this lab restriction, several research groups try to develop ambulatory measurement systems (e.g. [2]). This study presents an ambulatory measurement system for the measurement of the Ground Reaction Force (GRF), and the estimation of ankle and foot dynamics. METHODS The measurement system consisted of an orthopaedic sandal with two six degrees-of-freedom force/moment sensors beneath the heel and the forefoot (Figure 1). The position and orientation of heel and forefoot were estimated using the 3D accelerometer and 3D gyroscope of two miniature inertial ensors (Xsens Motion Technologies, http://www.xsens), rigidly attached to the force sensors. Moreover, a third inertial sensor was attached to the lower leg. The GRF was measured by the force/moment sensors beneath the shoe. A derivation of the calculation of the dynamics of ankle and foot can be found in [1]. The performance of the developed measurement system was evaluated by comparing the ambulatory measurement system with a reference measurement system, consisting of an optical measurement system (Vicon) and a force plate (AMTI). During the measurements, a healthy subject wearing the instrumented shoes, inertial sensors and optical markers, was asked to walk repeatedly over the force plate. In order to compare the signals measured with both measurement systems, a global coordinate system was defined with the x-axis pointing forward, the y-axis to the right, and the z-axis upward, resulting in a right-handed orthogonal coorinate system. RESULTS AND DISCUSSION The three components of the measured GRF of a healthy subject are shown in Figure 2. The signals measured with the instrumented shoe show good correspondence with the signals measured with the force plate, which is confirmed by the root-mean-square error between the magnitudes of the GRF, being 0.02 N/N or 1.8 % of the maximal magnitude. Figure 3 shows an integration of the measured GRF with the estimated position of the heel and forefoot sensor. The figure indicates the possibility of the ambulatory measurement system to measure several steps during a single measurement, which is not possible with the reference system. A detailed discussion about the performance of the ambulatory measurement system can be found in [1]. REFERENCES 1. Schepers HM, et al. IEEE Trans. Biomed. Eng., Accepted, 2007. 2.Baten CTM, et al. ISEK, Torino, Italy, 2006. ACKNOWLEDGEMENTS This research is part of the FreeMotion project, supported by the Dutch Ministry of Economic Affairs.

Human body movement analysis is commonly done in so-called 'gait laboratories’. In these laboratories, body movement is masured using optically based systems like Vicon, Optrotrak. The major drawback of these systems is the restriction to a laboratory environment. Therefore research is required to find ways for performing these measurements outside the gait laboratory. The estimation of foot movement is important, since balance is controlled by foot placement during gait. This study investigates whether it is possible to estimate foot movement, specifically foot placement, during gait under ambulatory conditions. The measurement system consisted of an orthopaedic sandal with two six degrees-of-freedom force/moment sensors beneath the heel and the forefoot. It should be noted that the force sensors were merely used for gait phase detection. The position and orientation of heel and forefoot were estimated using the accelerometers and gyroscopes of two miniature inertial sensors, rigidly attached to the force sensors [1,3]. In addition, errors in the walking direction were compensated for by using knowledge about the average walking direction. The proposed ambulatory measurement system was similar to the one used in a previous study [3]. In that study the position and orientation determination was restarted each step, while this study allows estimation of position and orientation during several steps including a change of direction. However, the accuracy should be investigated in more detail by an evaluation study. Moreover, the measurement system can be simplified by using a different gait phase detection system, for example by a gyroscope based detection system [2]. The financial support from the Dutch Ministry of Economic Affairs for the FreeMotion project is gratefully acknowledged. REFERENCES [1] H.J. Luinge and P.H. Veltink, “Measuring orientation of human body segments using miniature gyroscopes and accelerometers��?, Med. Bio. Eng. Comp., Vol. 43, pp. 273-282, (2005). [2] I.P.I. Pappas, M.R. Popovic, M.R. Keller, V. Dietz and M. Morari, “A reliable gait phase detection system��?, IEEE Trans. Neural Syst. Rehabil. Eng., Vol. 9, pp. 113-125, (2001). [3] H.M. Schepers, P.H. Veltink and H.F.J.M. Koopman, “Ambulatory assessment of ankle and foot dynamics��?, IEEE Trans. Biomed. Eng., Submitted, (2006).

Analysis of foot dynamics is important, especially for patients with foot impairments. However, this analysis is difficult with commonly used systems. This study presents an ambulatory system for the estimation of ankle and foot power using an instrumented shoe equipped with six degrees-of-freedom force/moment sensors and miniature intertial sensors. The results show good correspondence with results obtained from literature.

Previously, we demonstrated that enforced activation of signal transducer and activator of transcription 5 (STAT5A) in human cord blood (CB)-derived stem/progenitor cells results in enhanced self-renewal and impaired myelopoiesis. The present study identifies C/EBP alpha as a critical component that is down-regulated by STAT5. Microarray and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis on STAT5A(1.6)-transduced CD34(+) cells identified C/EBP alpha as the most prominently down-regulated gene. To determine the cell-biological relevance of these observations, a 4-OHT-inducible C/EBP alpha-ER protein was co-expressed with the STAT5A(1*6) mutant in CB COW cells using a retroviral approach. Re-expression of C/EBP alpha in STAT5A(1*6) cells resulted in a marked restoration of myelopoiesis. The proliferative advantage imposed on CD34(+) cells by STAT5A(1*6) depended on the down-modulation of C/EBP alpha, as reintroduction of C/EBPa induced a quick cell-cycle arrest and the onset of myeloid differentiation. Longterm culture-initiating cell (LTC-IC) frequencies were elevated from 0.8% +/- 0.6% to 7.8% +/- 1.9% by STAT5A(1*6) as compared with controls, but these elevated LTC-IC frequencies were strongly reduced upon re-introduction of C/EBP alpha in STAT5A(1*6) cells, and no second cobblestone area-forming cells (CAFCs) could be generated from double-transduced cells. Enumeration of progenitors revealed that the number of colony-forming cells (CFCs) was reduced more than 20-fold when C/EBP alpha was co-expressed in STAT5A(1*6) cells. Our data indicate that down-modulation of C/EBP alpha is a prerequisite for STAT5-induced effects on self-renewal and myelopoiesis.

Er zijn enkele presentaties gehouden over de ervaringen met de teelt van walnoten in Nederland tijdens het vijfde Internationale Walnotencongres in Sorrento, Italië, gehouden in november 2004. De productie van walnoten in Nederland stelt nog niet veel voor. Er is dus ruimte voor eigen productie

Er zijn enkele presentaties gehouden over de ervaringen met de teelt van walnoten in Nederland tijdens het vijfde Internationale Walnotencongres in Sorrento, Italië, gehouden in november 2004. De productie van walnoten in Nederland stelt nog niet veel voor. Er is dus ruimte voor eigen productie

Jongstleden 14 maart kwam onder andere burgemeester Havermans van Den Haag naar Leiden om in een forum van de Bll, te discussiëren over de regiovorming in de provincie Zuid-Holland. Aanleiding tot het forum was de toewijzing door het kabinet aan Rotterdam van de Stadsprovincie-status per 1 januari 1997. Havermans ging hierover in discussie met burgemeester Jansen van Krimpen a/d IJssel, eveneens vice-voorzitter van het Dagelijks Bestuur van de Stadsregio Rotterdam, en met mevrouw Van Grunsven, raadslid voor de Stadspartij Rotterdam. Deze partij werd vorig jaar voor de gemeenteraadsverkiezingen opgericht als protestpartij tegen de vorming van de Stadsregio Rotterdam. Het forum werd voorgezeten door de heer Neelen, docent Bestuurskunde in Leiden.

Interview met Barbara Bos, studente Bestuurskunde en actief betrokken bij hulpverleningsprojecten door jongeren in voormalig Joegoslavië

Het einde van de Koude Oorlog heeft niet geleid tot verwezenlijking van de idealen die ten grondslag lagen aan de oprichting van de Verenigde Naties (VN). Het aantal oorlogen en conflicten gevolgd door vredesacties van de VN lijkt alleen maar toegenomen. Hoe kan in deze situatie de VN worden omgevormd tot een organisatie die recht doet aan de werkelijkheid van mondiale verhoudingen en die tot effectief vredesbestuur kan overgaan?

Sinds milieu is gaan leven in ons land worden de burger en het bedrijfsleven overspoelt met vergaande overheidsregulering. In betrekkelijk korte tijd wist de Haagse bureaucratie dit nieuwe terrein uit te melken, zichzelf voorziend van een belangrijk nieuw beleidsterrein. Het Nederlandse milieubeleid is gebaseerd op het principe 'de vervuiler betaalt.' Maar waarom niet afstappen van die excessieve regulering en bemoeienis en invoering van een nieuw principe, namelijk 'de vervuiler krijgt zèlf de mogelijkheid zijn vervuiling aan te pakken.'

Het regeerakkoord van Winsemius: een structurele verbetering van de economie door het verwijderen van inefficiëntie (met name in het maatschappelijk middenveld) en een idealistischer arbeidsmoraal bij pas afgestudeerden.