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In this paper, the problem of modeling a pneumatic semi-rotary actuator for precise control in the presence of friction for future robotic manipulator applications is addressed. Precise commercial pneumatic components have become increasingly available and are widely applied in the processes and manufacturing industry. The robustness of pneumatic actuator solutions is limited by the precision of the system controller positioning, which depends on sophisticated algorithms that must deal with the highly nonlinear nature of the pneumatic system operation by means of the use of controllers that require suitable system knowledge. In this study, aiming at obtaining such a suitable model for a class of pneumatic semi-rotary actuator, the pressure dynamics in its chambers is modeled. The overall modeling task involves a detailed experimental identification of the curves of the mass flow rate related to the control voltage of the servovalve and its relationship with the pressures in the piston chambers. Moreover, friction was formulated with the LuGre model on account of its ability to represent different effects that comprise friction phenomena, including Coulomb, viscous and static friction effects, resulting in a comprehensive mathematical model for supporting future development of a nonlinear controller. Finally, validation in open loop was performed with comparisons between experimental and simulation results.

A gas sensor based on spontaneous Raman scattering is proposed for the compositional analysis of single breath events. A description of the sensor as well as of the calibration procedure, which also allows the quantification of condensable gases, is presented. Moreover, a comprehensive characterization of the system is carried out in order to determine the measurement uncertainty. Finally, the sensor is applied to consecutive breath events and allowed measurements with 250 ms time resolution. The Raman sensor is able to detect all the major gas components, i.e. N2, O2, CO2, and H2O at ambient pressure with a high temporal resolution. Concentration fluctuations within a single breath event could be resolved.

Спонтанное рамановское рассеяние представляет собою прекрасный метод количественного анализа многокомпонентных газовых смесей. Это неразрушающий оптический метод идентификации состава вещества и измерения концентрации компонентов газа, включающих в себя рамановские активные молекулы. При этом интенсивность специфического рамановского сигнала прямо пропорциональна концентрации. При использовании лазерного излучения в непрерывном режиме при комнатной температуре требуется всего несколько секунд для получения рамановского спектра газовой смеси. В то же самое время серьезным недостатком метода является малая интенсивность рамановского сигнала. По этой причине существует проблема детектирования состава газовой смеси по рамановским спектрам при низких давлениях компонентов газа с временным разрешением порядка сотен миллисекунд. В данной работе представлена конкретная работающая система газового анализа на основе рамановского рассеяния при низких давлениях компонентов (абсолютное давление p ≥ 980 гПа). Применение многопроходной полости позволяет компенсировать слабую величину рамановского сигнала. Более того, работоспособность представленной сенсорной системы продемонстрирована измерениями в ходе процедуры анестезии в конкретных клинических условиях и при сопоставлении результатов измерений с обычно применяемыми средствами газового анализа., The spontaneous Raman scattering technique is an excellent tool for a quantitative analysis of multi-species gas mixtures. It is a noninvasive optical method for species identification and gas phase concentration measurement of all Raman active molecules, since the intensity of the species specific Raman signal is linearly dependent on the concentration. Applying a continuous wave (CW) laser it typically takes a few seconds to capture a gas phase Raman spectrum at room temperature. Nevertheless in contrast to these advantages the weak Raman signal intensity is a major drawback. Thus, it is still challenging to detect gas phase Raman spectra in alow-pressure regime with a temporal resolution of only a few 100 ms. In this work a fully functional gas phase Raman system for measurements in the low-pressure regime (p ≥ 980 hPa (absolute)) is presented. It overcomes the drawback of a weak Raman signal by using a multipass cavity. A description of the sensor setup and of the multipass arrangement will be presented. Moreover the complete functionality of the sensor system will be demonstrated by measurements at an anesthesia simulator under clinical relevant conditions and in comparison to a conventional gas monitor.

Science-based planning and prioritization can help achieve greater return on investment of limited con- servation funds. We conducted a GIS-based multicriteria decision analysis to prioritize efforts to eradicate populations of invasive alien species that threaten native biota on the islands of Mexico. We evaluated 29 Mexican islands with docu- mented presence of invasive mammals and characterized the following attributes of each island: presence of endemic taxa, presence of threatened species, presence of important seabird nesting areas, species richness, likelihood of reinva- sion, eradication feasibility, and economic cost. We categorized the islands into 4 priority categories for eradication action. The highest priority islands where eradication efforts are feasible are Socorro, Espiritu Santo, Maria Cleofas, and Maria Magdalena islands, where eradication of 11 invasive mammal populations could advance the restoration of an additional 35,813 ha, thereby reducing the extinction risk of approximately 80 endemic taxa. RESUMEN.—La planeacion sistematica y priorizacion es fundamental para lograr mayor eficiencia de inversion de fondos limitados para la conservacion. Se aplico un analisis multicriterio por medio de Sistemas de Informacion Geogra- fica para priorizar esfuerzos de erradicacion de poblaciones de especies invasoras que amenazan la biota de las islas mexicanas. Se evaluaron 29 islas con presencia de mamiferos invasores, para lo cual se caracterizaron los siguientes atributos de cada isla: presencia de especies endemicas, presencia de especies amenazadas, presencia de sitios impor- tantes de anidacion de aves marinas, riqueza de especies, probabilidades de reinvasion, factibilidad de erradicacion y el costo de su ejecucion. Se clasificaron las islas en 4 categorias de prioridad de erradicacion. Las islas con mayor prioridad donde la erradicacion es factible son Socorro, Espiritu Santo, Maria Cleofas y Maria Magdalena, donde erradicando 11 poblaciones especies invasoras se restaurarian 35,813 ha, reduciendo el riesgo de extincion de 80 especies endemicas.

The Arctic is a new frontier that opens up new possibilities and industrial potential. However, the Arctic has a fragile marine environment with one of the world’s most fertile ecosystems. Therefore, taking into account the limitations in available infrastructure in general, there is a need for improved navigation services in this area. Large parts of the Arctic are presently not covered by SBAS services, so improving SBAS coverage would be a significant contribution. On this basis, the Arctic Testbed is a stand-alone SBAS prototype system set up to show how SBAS can support the users in the Arctic in obtaining safe navigation services. The testbed has been developed in the framework of the European GNSS Evolution Programme (EGEP) of the European Space Agency (ESA). The plans for Arctic Testbed, as well as simulation results, were presented at ION 2013 [1]. Now the system is completed and in use for experiments and demonstrations. The main objective of Arctic Testbed is to contribute to extending secure satellite navigation in the Arctic region. In particular, it will complement EGNOS in the north, targeting coverage up to a latitude of 85 degrees north. Further, it will extend coverage to the west, bridging the gap between EGNOS and WAAS in the northern Atlantic. This paper presents the results from experiments with this testbed. The Arctic Testbed, being a stand-alone prototype, allows making extensive experimentation without affecting operational users. The Arctic Testbed is built from the algorithms used in the EGNOS Central Processing Facility (CPF), but extended with additional functionalities. This allows investigating how these various enhancements affect EGNOS performance. More in detail, the following improvements are analysed: • The use of alternative means, other than geostationary satellites, to broadcast EGNOS corrections. These include Internet, Iridium and Automatic Identification System (AIS). As a result, users beyond the geostationary satellite coverage can still receive the differential corrections and calculate an augmented Position, Velocity and Timing (PVT) solution. • The calculation of differential corrections for a second constellation (GLONASS) further than GPS. This option provides more observables at both the system and the user levels. Therefore, the robustness of the PVT solution is potentially improved. • The user estimation of ionospheric delay from dual frequency observations, and then combined with clock/orbit corrections from SBAS. • The extension of the reference stations network, hence providing more observables to the system. • The combined use of EGNOS and WAAS in the region of overlapping coverage of the two systems (deviation from the DO229D methodology as required in aviation) The methodology is based on experiments which result in a navigation performance assessment at the user level. This is done for the complete service area, as well as for specific locations. These performance indicators are then compared to the current EGNOS system and to the simulated results. This approach allows concluding on whether the enhancements will have any impact on EGNOS, and allows verifying that the simulations are representative of the actual performance. The paper presents the performance of the different enhancements mentioned above. More in detail, for each option, the relevant performance is shown with coverage maps, Stanford plots, time-series plots and other statistical indicators. The paper shows how enhancements to EGNOS might benefit users in the Arctic region. However, it also demonstrates in a more generic sense the advantages of using an additional constellation and dual frequency observations. Therefore, the proposed assessment can be considered as representative of the performance which can be obtained in a future Dual Frequency Multiple Constellation system with GPS/Galileo/BeiDou/- GLONASS operating in dual frequency (L1/L5). The Arctic Testbed project is initiated by ESA. Kongsberg Seatex is assigned as prime contractor, heading a team of eight partners: GMV Aerospace and Defence, Thales Alenia Space France, CGI, Terma, Norwegian Mapping Authority, Technical University of Denmark, Septentrio and University of Calgary.

History A 62 year-old male patient developed malaise, unproductive cough and high temperature (39.5 degrees C) during immunosuppressive therapy with methylprednisolon and cyclosporin A six months after kidney transplantation for glomerulonephritis. Investigations Clinical examination revealed an endophthalmitis and chest X ray a left-sided lobar pulmonic infiltration. Computed tomography and magnetic resonance imaging examination performed because of recurrent petit-mal-convulsions demonstrated multiple intracranial infiltrations. Transoesophageal echocardiography revealed floating vegetations up to 8 mm in diameter predominantly attached to the aortic valve. A total of 39 consecutive blood cultures drawn during several days remained sterile. However, Nocardia asteroides (Biovar A1) was isolated from a small cutaneous tumor excised from the right thigh. Treatment and course After initiation of a specific antibiotic treatment with imipenem/cilastatin (each 1 g three times daily), and doxycyclin (100 mg twice daily), computed tomography and magnetic resonance imaging showed a reduction in size and number of the intracranial infiltrations. Neurological symptoms were progressive despite maximal anticonvulsant therapy. The patient died 83 days after hospital admission from an epileptic state resistant to therapy. Conclusion Though nocardiosis is still rare, it should early be included in the differential diagnosis of infections in immunocompromised patients to allow timely diagnosis and therapy.

When GPS navigation system radio waves pass trough the ionosphere and plasmasphere they are subject to delays in phase, travel time and polarisation, owing to the presence of free electrons. The integrated values of Total Electron Content can be used for 3-dimensional reconstruction of ionospheric electron density patterns. Here a tomographic approach is presented. Since the input data are sparsely distributed and patchy we chose an algebraic iterative algorithm. A plasma convection event has been taken as a tomographic case study. The addition of limb sounding GPS from Low Earth Orbiter satellites improves reconstructions of the vertical shape of the ionosphere by its horizontally viewing rays. A reconstruction including an occultation event is presented and the results are validated using an ionosonde profile.

Space weather monitoring and forecast require a permanent monitoring of the ionospheric state on global scale. The world-wide use of global navigation satellite systems such as GPS and GLONASS o7ers the unique chance for a permanent monitoring of the total ionization (total electron content—TEC) of the global ionosphere=plasmasphere up to about 20000 km height. In this study we turn our attention to TEC variations over the European area. Using the data of more than 15 GPS stations of the GPS tracking network of the International GPS Service (IGS), a horizontal resolution in the order of 500 km is achieved, the standard time resolution is 10 min. The total ionization of the ionosphere reacts very sensitive to solar radiation changes. As correlation studies with the solar radio =ux index F10.7 have shown, the ionospheric response over the European area is delayed by about 1–3 days depending on geophysical conditions. Consequently, the turn o7=on of the solar radiation during the solar eclipse on August 11, 1999 was seen as a signi@cant reduction of TEC following the obscuration function with a delay of up to 40 min. Ground-based GPS measurements can e7ectively be used for detecting large-scale horizontal structures and their motion (up to 30 s time resolution) during perturbation processes (see http://www.kn.nz.dlr.de/). These capabilities are demonstrated by analyzing individual storms of January 10, 1997 and of April 6, 2000. For the latter also TEC maps of the Northern polar cap down to 50 ◦ N were computed. These polar maps indicate strong ionization enhancements around the geomagnetic pole in the evening hours. Furthermore, simultaneous high rate sampled GPS and GLONASS data are presented that demonstrate the impact of perturbation-induced small-scale irregularities in the ionosphere on satellite signals in operational communication and navigation systems. c

In einer prospektiven Studie wurde die Schilddrusenstoffwechsellage bei 102 Patienten, welche sich einer Koronarangiogaphie unterziehen mussten, unter Berucksichtigung der Schilddrusenmorphologie untersucht. Vor der intraarteriellen Kontrastmittelgabe und drei Wochen nach dem Eingriff wurden die Serumkonzentrationen von „TT3, rT3, TT4, fT4 und TSH“ sowie die Urinjodausscheidung gemessen. In die Untersuchung wurden nur Patienten mit euthyreoter Schilddrusenfunktion eingeschlossen, um die Frage zu beantworten, ob und in welchem Ausmas die intraarterielle Gabe nichtionischen jodhaltigen Kontrastmittels die Schilddrusenfunktion bei euthyreoten Patienten in Abhangigkeit von der Schilddrusenmorphologie beeinflusst und ob die Schilddrusenmorphologie einen prognostischen Faktor fur das Hyperthyreoserisiko darstellt. Es wurde eine Ultraschalluntersuchung der Schilddruse durchgefuhrt und der Autoantikorperstatus (TPO-Ak, TG- Ak, TSH-Rezeptor-Ak) der Patienten ermittelt. Entprechend der Ultraschallbefunde wurden 4 verschiedene Schilddrusenmorphologien unterschieden: normale Schilddrusen (n=37), normal grose knotig veranderte Schilddrusen (n=16), diffuse Strumen (n=15) und Knotenstrumen (n=34). 25 Patienten wiesen TG-Ak auf, 13 Patienten TPO-Ak. Bei keinem der Patienten waren TSH-Rezeptor-Antikorper nachweisbar. Die Serumspiegel von TT3 anderten sich nicht signifikant nach der Jodgabe (p=0,30), wahrend TT4 und fT4 signifikante Veranderungen in allen 4 morphologischen Gruppen zeigte (fT4 p

The world-wide use of GPS satellites for navigation and positioning offers a unique chance for permanent monitoring the total electron content (TEC) of the ionosphere on regional/global scale. Using permanent operating GPS ground station networks (e.g. that from IGS) the derived TEC maps may contribute to monitor the actual development of large scale structures in electron content and their dynamics during ionospheric perturbations (e.g.www.kn.nz.dlr.de/ → Ionosphere Impact → Storm). Based on GPS measurements at European IGS ground stations and subsequent TEC estimations and mapping, both individual as well as common features of ionospheric storms shall be discussed for the European ionosphere. The paper demonstrates the power of this new GPS tool to detect and to study the dynamics of large-scale spatial structures (e.g. ionospheric response of solar eclipse on 11 August 1999). Detected TEC-perturbations are closely related to space weather characterizing quantities such as solar radio emission, solar wind and geomagnetic activity indices. Due to close relationships between TEC and space weather parameters a permanent space weather monitoring can help to control the ionospheric impact on operational navigation satellite systems.

The detection of minimal residual disease (MRD) is a major prognostic factor for treatment in acute lymphoblastic leukemia (ALL) of childhood. Several groups showed the predictive value of MRD after 5 weeks of chemotherapy (at the end of induction therapy). Patients with more than 1 leukemic cells in 100 cells (≥ 10 -2 ) at this time-point have a significantly higher relapse rate. The MRD measurement has been shown to be an independent prognostic factor at several time points in the BFM study (ALL-BFM 90) as well as in the EORTC study. The aim of our investigations was the detection of MRD at the end of induction therapy within the COALL studies which is different from the above studies. In the COALL studies, therapy starts with a 1 week DNR prephase (24 h infusion on day one) and i.th. MTX. Induction therapy consisted of 3 drugs over a period of 4 weeks (Prednisolone, Vincristine and Daunorubicin), asparaginase is given later in consolidation. At the end of induction therapy, bone marrow was obtained for cytomorphologic and molecular analysis. Patients and Methods: We investigated bone marrow samples from 76 patients. All patients were in morphologic remission at the end.

Measurements at GPS ground stations of the International GPS Service (IGS) havebeen used to derive the total electron content (TEC) of the ionosphere over Europe and overthree North American stations for the 6–11 January 1997 storm event. The derived TEC dataindicate large deviations from the average behaviour especially at high latitudes on thenight-side/early morning longitude sector. The high-latitude perturbation causes a well-pronounced positive phase on the day-sidesector over Europe. Both meridional winds as well as transient electric fields are assumed to contribute to thesignature of the ionospheric perturbation propagating from high to low latitudes. Theobservations indicate a subsequent enhanced plasma loss which is probably due to theequatorward expansion of storm induced composition changes.

Synchrotron-based x-ray computed microtomography contributes high-resolution, three-dimensional observations to investigations of multiphase fluid transport in porous media. Pore-scale observations are valuable to the development and validation of new theory, as well as numerical models. Computed microtomography has been used previously to measure fluid content and interfacial areas in systems containing two fluids (air-water, oil-water) and to a limited extent to measure fluid content and entrapped fluid morphology in systems containing three fluids (air-oil-water). This study addresses challenges that arise when imaging three-phase flow in spreading systems. The first challenge is related to wettability alteration. Observations reported herein suggest that the wettability of solid surfaces changed over the course of a three-fluid phase flow experiment, a phenomenon that has not been observed in similar, previously conducted two-fluid phase experiments. Follow-up experiments showed that wettability alteration is significant when oil-solid contact is combined with x-ray exposure, and is not reversed with a conventional cleaning procedure. The second challenge arises in segmenting three-phase images, and thereby obtaining data from which various measures can be quantified with sufficient accuracy. Partial volume effects and blur often cause the grey-scale values of different fluids to overlap and appropriate steps must be taken to avoid ambiguity at phase boundaries. A comparison of images collected at standard resolution (10.6 microns voxel(-1) ) to those collected at a higher resolution (5.3 microns voxel(-1) ) showed that saturation measurements are within 5% of each other, but interfacial areas for three-phase systems may be underestimated at standard resolution by as much as 25%.

BCR is a modular structured computer program for the simulation of bubble column reactors. It offers very comprehensive options for process engineering calculations for steady-state bubble columns with or without internal installations under various operation modes by determining the local pressure, temperature and concentration profiles over the column height. With the implemented computational methods, new equipment can be analyzed and optimized or the operation range of existing bubble column reactors can be checked and in some cases extended. Potential users are research and development departments in the chemical industry and universities, or research institutes with activities in the field of multiphase reaction engineering. In this contribution, the main program features are described and a short overview is given regarding the calculation methods for fluid dynamic parameters, mass- and heat-transfer coefficients and reaction kinetics in the bubble column, and about methods for considering internal installations such as sieve trays or tube bundle heat exchangers. Some examples are given showing axial temperature and concentration distributions for a bubble column reactor (D = 2 m, H = 20 m) designed for the wet air oxidation of a sewage sludge suspension.

The mathematical equations and a comprehensive computer program for modeling and simulating bubble column reactors with internal heat exchange installations are presented. Detailed reactor model equation systems on the basis of the axial dispersion model and the cell model with backflow are developed by linking together the mathematical description o the multiphase flow properties with the momentum, mass and energy balances of the reactor. A highly modular constructed computer program is presented summarizing a lot of theoretical and empirical knowledge about multiphase flow and heat and mass transfer processes in bubble columns. The enhanced possibilities of this new software system are demonstrated by simulating two industrial processes. The methanol synthesis in the slurry phase is chosen in oder to test the model accuracy for a multicomponent reaction system including a hermodynamically balanced chemical reaction. Secondly, the wet air oxidation of municipal sewage sludge in a large-scale slurry bubble column reactor is simulated as an example of a highly exothermic oxidation carried out at extreme pressure and temperature conditions. This chemical process requires special attention for reaction heat removal. The numerical treatment of the algebraic equation system based on the cell model with backflow is easier and leads to average computing times up to 100 times lower than for the reactor model based on the axial dispersion model. The iteration process for solving the boundary value problem runs into numerical convergence difficulties for the case of highly exothermic process conditions with considerable temperature gradients in the reactor. So the finite-difference technique cannot be recommended from a numerical point of view, whereas the cell model formulation allows computations on an IBM-compatible PC (386, 25 MHz) with tolerable computing times of the order of minutes.

Al jarenlang wordt ijs gebruikt om postoperatieve pijn en zwelling te bestrijden. Door de ontwikkeling van halfopen en gesloten koelsystemen zonder smeltwater kon de toepassing vereenvoudigd worden. De applicaties kunnen vlakbij het wondgebied aangebracht worden, wat met ijsgruis om hygienische redenen problematisch is. De analgetische werking van de cryotherapie wordt neurofysiologisch op twee verschillende manieren verklaard. De traditionele zienswijze gaat uit van een unidimensionaal verloop van afferente pijnvezels die lineair uitmonden in de cellen van de tractus spinothalamicus.

In a prospective study, thyroid metabolism in 102 patients undergoing diagnostic coronary angiography was investigated, stratified for thyroid morphology. The thyroid function serum parameters "TT3, rT3, TT4, fT4 and TSH" and the urinary iodine excretion were measured before and three weeks after diagnostic intraarterial administration of the iodine-containing contrast agent. Only patients with euthyroid function were included in order to answer the questions whether or not the administration of non-ionic iodine containing contrast medium leads to significant thyroid function changes in euthyroid patients and whether thyroid morphology is a prognostic factor for the risk of developing hyperthroidism. Serum concentrations of thyroid autoantibodies (TPO-Ab, Tg-Ab, TSH-receptor-Ab) were measured and thyroid ultrasound was performed. According to the ultrasound findings, 4 morphologic groups were formed: normal thyroid glands (n = 37), normal sized but nodular glands (n = 16), diffuse goiter (n = 15) and nodular goiter (n = 34). Twenty-five patients were positive for Tg-Ab; TPO-Ab were found in 13 patients. TSH-receptor-Abs were not detected in all patients. TT3 levels did not significantly change after iodine application (p = 0.30). TT4 and fT4 levels showed significantly different alterations in the 4 groups (fT4 p0.001). The amount of iodine given did not influence alteration of serum concentrations of TSH (p = 0.67), TT3 (p = 0.68), TT4 (p = 0.37), fT4 (p = 0.92) and rT3 (p = 0.81). Elevated levels of urinary iodine excretion correlated with the amount of contrast medium given (p = 0.087). Albeit there was a high number of nodular transformed glands and goitrous patients included, and our cohort was recruited in an iodine deficient area, we did not observe hyperthyroidism in any patient. However, thyroid function parameters are significantly altered after coronary angiography independent of antibody status and the amount of contrast agent given, but dependent on thyroid morphology.

MRD at the end of induction therapy in childhood acute lymphoblastic leukemia: outcome prediction strongly depends on the therapeutic regimen

The detection of minimal residual disease (MRD) is a major prognostic factor for treatment in acute lymphoblastic leukemia (ALL) of childhood. Several groups showed the predictive value of MRD after 5 weeks of chemotherapy (at the end of induction therapy). Patients with more than 1 leukemic cells in 100 cells (or = 10(-2)) at this time-point have a significantly higher relapse rate. The MRD measurement has been shown to be an independent prognostic factor at several time points in the BFM study (ALL-BFM 90) as well as in the EORTC study. The aim of our investigations was the detection of MRD at the end of induction therapy within the COALL studies which is different from the above studies. In the COALL studies, therapy starts with a 1 week DNR prephase (24 h infusion on day one) and i.th. MTX. Induction therapy consisted of 3 drugs over a period of 4 weeks (Prednisolone, Vincristine and Daunorubicin), asparaginase is given later in consolidation. At the end of induction therapy, bone marrow was obtained for cytomorphologic and molecular analysis.We investigated bone marrow samples from 76 patients. All patients were in morphologic remission at the end. of induction therapy. For MRD analysis, DNA was isolated from bone marrow mononuclear cells. Clonal T-cell-receptor (TCR) or immunoglobulin gene (IgH) rearrangements were identified by PCR. Monoclonal products were either sequenced directly (TCR) or after excision from high resolution agarose gels. Subsequently patient-specific oligonucleotides for allele-specific PCR were generated. PCR analysis was performed with 1 microgram DNA for each reaction within a semiquantitative matter. This method reached sensitivities down to 10(-5).Eighty-four percent of the analysed samples were MRD positive at the end of induction therapy. 20 out of 76 patient samples (26%) were highly positive (or = 10(-2)), 28 patients had levels of about 10(-3) (37%), 16 had levels around 10(-4) (21%) and 12 patients had no detectable residual cells (16%). All analysed 15 T-ALL patients had detectable residual disease at this timepoint. Until now, 5/20 patients with very high MRD level at the end of induction therapy suffered a relapse.Patients with very high MRD level at the end of induction therapy showed an elevated risk of relapse, but the predictive value is much poorer than for example in the BFM 90 MRD-study. We suggest, that a high MRD level at this timepoint results from a different induction therapy compared to the BFM 90 study. In the COALL studies asparaginase is given only after induction therapy to decrease the risk of thrombosis. We would like to conclude that this differences were compensated later during therapy as the event free survival of both studies is similar. In conclusion, an optimal information from MRD studies is strongly associated with the given therapy. Therefore we initiated an additional MRD time-point after the first chemotherapy block in consolidation.

This paper presents a model of stirred tank reactors, which is able to solve the dynamic mass and energy balances on the basis of certain fluiddynamic, simplifications. One possibility is to give a macroscopic flow field as an input, but it is more suitable to fit local distributions of velocities to the reactor model. To close the model, empirical knowledge for the required model parmeters is included in form of empirical equations.

The article will describe a multiprofessional (nurses, social workers, teachers, psychologists, physicians) treatment in a child psychiatric daycare-clinic. In that context the importance of relationship as an equivalence to the "primary motherliness" for early-disturbed children will be stressed. Further the article will focus on the relevance of continuous "post-education" and the broadening of the children's cognitive range by way of this object relation. Also, the article will inform about the uncovering psychotherapy with the children and their parents and about the importance of informations both from the therapists to the team as the other way round. Based on case studies it will be demonstrated how the multiprofessional team functioning as a "whole object" becomes instrumental for patients to work through affective relationships and mechanisms of defence.

We have recently reported a reduction of pattern electroretinogram (p-ERG) in patients with HIV infection. Amplitudes were reduced in HIV-infected patients with microangiopathy, but also in some cases with normal fundus. These findings suggested the existence of diffuse defects in ganglionic cell activity in HIV-infected patients. We have now started a prospective follow-up study in order to pursue the development of (a) p-ERG amplitudes and (b) funduscopic changes and visual acuity in these patients. In patients with normal fundus or microangiopathy who did not develop cytomegalovirus (CMV) retinitis, no significant tendency for the p-ERG amplitudes to fall could be demonstrated during the observation period of 1-16 (mean: 7) months. With the appearance of retinitis, the p-ERG amplitude decayed. In some cases, a pathologic p-ERG was recorded before retinitis appeared: 3 of 12 patients with p-ERG amplitudes in the pathological range later developed CMV retinitis and only 1 of 21 patients with normal p-ERG later developed retinitis. In some patients with AIDS or related disorders, p-ERG may be a useful additional diagnostic tool.

The various Public Health offices in North Rhine Westphalia are making a substantial contribution towards AIDS prevention means of their relevant concepts. Regional and political individualities as well as local structures can exercise a positive or a negative effect on concrete AIDS prevention work. Cities like Düsseldorf, Köln, Essen etc., enjoy material and personal advantages. Smaller communities (like Bottrop) must rely entirely on creative working concepts. The AIDS prevention concept of Bottrop (a city situated in the northern Ruhr area with a population of 120,000), consisting of sexual education and paedagogical approaches, is presented. The information aims at specific groups, but has no ideological strings attached. The report refers to five main points of working: 1. AIDS prevention with special attention to adolescents in school and out-of-school contexts. 2. Medical advice by institutions. 3. Daily AIDS consulting hours in the Public Health office. 4. Planning and realisation of an action day 'Health Day'. 5. Working with drug addicts. In addition, there is an epidemiological approach. The overall aims are the prevention or infection and a human psychosocial spectrum of advice without excluding anyone.