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Na het letterlijk citeren van enkele auteurs die over het pluis/niet-pluisgevoel hebben gepubliceerd staan de auteurs in hun commentaar stil bij het diagnostisch proces en vestigen de aandacht op het belang van het expliciet maken van factoren uit context, anamnese en onderzoek die op rationele gronden tot beleid leiden. In het vervolg wordt eerst besproken wat een diagnose is en het diagnostisch proces plus de invloeden op dat proces. Dan wordt de diagnostische onzekerheid onder de loep genomen, die gezien kan worden als een onvermijdelijke rationele en reproduceerbare tussenuitkomst en in het bijzonder de onzekerheid in de huisartsenpraktijk. Besloten wordt met de samenvatting dat het pluis/niet-pluisgevoel een uitgangspunt is voor (zelf)evaluatie maar niet voor medische beslissingen.

For the assessment of the safety of the Dutch flood defences extreme open-water winds need to be computed. There are, however, no sufficiently long and reliable in-situ data available. On the other hand, there is a rich dataset of decades of measurements at certain coastal and relatively close by inland stations. A commonly used two-layer model for neutral atmospheres was thought to provide reasonably accurate open-water winds from the available data, given that the model assumptions seemed plausible for the extreme winds of interest. However, the model results were deemed inaccurate and not usable. Given that this was unexpected, many of the model assumptions were analysed and, with the gained further insight, their validity and contribution to the invalidity of the deemed simple model approach assessed. Our conclusion is that the quality of the model results is significantly affected by at least two aspects: the assumption of neutral stability in the model, and – equally important – the assumption of independence between the surface roughness and the wind speed.

Inleiding: Sekse speelt een rol bij medische zorg. In toenemende mate wordt van huisartsen verwacht dat zij rekening houden met contextuele factoren waaronder sekse. In het raamplan van de huisartsopleidingen zijn seksespecifieke competenties beschreven. Om huisartsen in opleiding deze competenties te laten verwerven is onderwijs in seksespecifieke huisartsgeneeskunde noodzakelijk. Methoden: Er is een curriculum ontwikkeld, bestaande uit vijf modules, waarin de seksespecifieke competenties zijn uitgewerkt. Er worden evidence-based leermethoden gebruikt om aios huisartsgeneeskunde seksespecifiek medisch handelen te leren (interactief, praktijkgericht, reflectief). Het seksespecifieke curriculum is een geintegreerd onderdeel van de huisartsopleiding. Tussen 2005–2008 is na elke module de aios gevraagd een evaluatieformulier in te vullen met de bedoeling het onderwijs te evalueren en leerpunten te inventariseren. Resultaten: De modules van het betreffende onderwijsprogramma zijn verdeeld over de driejarige huisartsopleiding. In het onderwijs worden seksespecifieke onderwerpen behandeld met een hoge huisartsgeneeskundige relevantie zoals de arts-patient communicatie, hart- en vaatziekten en depressie. De evaluatie van het onderwijs is overwegend positief. De geformuleerde leerpunten van de aios sluiten aan bij de competenties van het seksespecifieke onderwijsprogramma. Discussie en conclusie: Met succes is een seksespecifiek onderwijsprogramma geimplementeerd in de Nijmeegse huisartsopleiding. De evaluatie laat zien dat het onderwijs in seksespecifieke huisartsgeneeskunde positief wordt gewaardeerd. Daarnaast draagt het onderwijs bij aan een besef van de invloed van de factor sekse in de dagelijkse medische praktijk. De modulaire opbouw en de competentiegerichte onderwijsmethoden maken het geschikt voor andere huisartsopleidingen. (Dielissen PW, Bottema BJAM, Verdonk P, Lagro-Janssen ALM. Geintegreerde seksespecifieke huisartsgeneeskunde in de Nijmeegse huisartsopleiding: competenties, opzet en evaluatie. Tijdschrift voor Medisch Onderwijs 2010(29);3:200–209.)

Inleiding: Aan het derde jaar van de huisartsopleiding is de keuzemodule ‘Differentiatie’ toegevoegd. Met deze curriculumvernieuwing wordt beoogd de huisarts-in-opleiding (aios) maatwerk te bieden tijdens de opleiding en een aanzet te geven voor een persoonlijke ontwikkeling in de latere beroepspraktijk. Voor deze module stelt de aios bij een zelfgekozen differentiatie- onderwerp een plan op met doelen, activiteiten en tijdsbesteding. In een evaluatiestudie zijn de meningen van aios, huisarts-opleiders (hao’s) en docenten over de praktische uitvoering onderzocht.

Various models for calculating the effective or area-averaged roughness length zoe have been tested for a partly forested area. Three types of model are considered: the tile approach for very large scales of inhomogeneity (> 20 km), drag models for very small scales (up to 1 km), and surface-layer methods such as the blending-height method for intermediate scales. Over partly forested areas, where both pressure effects and roughness sub-layer effects may become significant, small-scale models are expected be the most suitable type of model. The various model types were tested against new experimental data that were obtained over the partly forested Sherwood Forest area (UK). The best fit with the data was obtained with the blending-height method, rather than with the different small-scale models. This is remarkable as the surface-layer assumptions of the blending-height method were clearly violated: the calculated blending height was 7 m, as compared to the mean tree height of 20 m. Of the small-scale models, a sparse-canopy approach compared poorly with the experimental data. The drag models overestimated the area-averaged roughness to a lesser degree, but a major point of concern remains the choice of the model parameters. Therefore, suggestions are made for an improved choice of these parameters.

The Space Telescope Imaging Spectrograph (STIS) instrument was installed on the Hubble Space Telescope (HST) during the second servicing mission, in 1997 February. Four bands cover the wavelength range of 115–1000 nm, with spectral resolving powers between 26 and 200,000. Camera modes are used for target acquisition and deep imaging. Correction for HST's spherical aberration and astigmatism is included. The 115–170 nm range is covered by a CsI MAMA (Multianode Microchannel Array) detector and the 165–310 nm range by a Cs2Te MAMA, each with a format of \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cy...

The Space Telescope Imaging Spectrograph (STIS) was successfully installed into the Hubble Space Telescope (HST) in 1997 February, during the second HST servicing mission, STS-82. STIS is a versatile spectrograph, covering the 115-1000 nm wavelength range in a variety of spectroscopic and imaging modes that take advantage of the angular resolution, unobstructed wavelength coverage, and dark sky offered by the HST. In the months since launch, a number of performance tests and calibrations have been carried out and are continuing. These tests demonstrate that the instrument is performing very well. We present here a synopsis of the results to date.

We simulate the multiple scattering effects occurring in an ({ital e},2{ital e}) experiment for a free-electron solid. Realistic cross sections for elastic and inelastic scattering events are used, for all the electrons involved. The aim of this paper is to simulate a real ({ital e},2{ital e}) experiment, and investigate how the multiple scattering parameters used affect the relation between the electronic structure of the solid and the actually measured intensity. Good agreement is found, on a semiquantitiative level, between the simulations and the actual experiments. {copyright} {ital 1996 The American Physical Society.}

Dat luchtwegklachten en longaandoeningen heel veel voorkomen, kan elke Nederlander uit eigen ervaring wel vertellen. Veel klachten en verschijnselen komen niet eens ter kennis van een arts en verdwijnen zonder medisch hulp. Aan de huisarts worden zij in zeer uiteenlopende stadia gepresenteerd. Van eenvoudige verkoudheid tot ernstige pneumonie met kortademigheid.

Image motion compensation by servocontrolled tilt of the secondary mirror is applied in a 40-cm diam f/7.5 Cassegrainian balloon-borne telescope. A tilted-aplanatic configuration is used, i.e., the mirrors are aspherized to render the stabilized image free of third-order coma. A spatial resolution of 2 sec of arc is maintained in the presence of pointing errors up to 10 min of arc. The most important remaining aberrations are third-order astigmatism and fifth-order spherical aberration. For the latter, a general expression is presented that can also be applied to other two-mirror telescopes.

One second of arc pointing accuracy has been achieved by servocontrolling the secondary mirror of a Dall-Kirkham telescope flown in an Aerobee 150 rocket. The primary mirror is weight-relieved, mounted at its nodal line and can resolve 2 arc sec. An objective LiF prism mounted near the focal plane provides a lowresolution far uv spectrum suitable for studying planetary atmospheres. Solar blind photomultiplier tubes with pulse counting electronics provide a dark current background of less than 1 count/sec. Spectra of Venus, Jupiter and eta Ursa Majoris (U Ma) were obtained in a flight from White Sands, New Mexico, on 5 December 1967. Further flights are planned with the recovered package.

Two methods of off-set sun-tracking are described which were developed as part of the balloon-astronomy program of The Johns Hopkins University for daytime observations of the planet Venus. The performance of the system in flight, while subject to oscillations in the suspension system, is discussed.

Calculations using a second-order algebraic stress model are compared with wind tunnel and full-scale measurements for flow over a two-dimensional obstacle. The experiments show mutually good agreement. Outside the cavity, i.e. in front of the obstacle and at a distance of five obstacle heights downwind, calculations and experiments yield the same velocities and turbulent kinetic energies. However, in the cavity comparison is poor. This is caused by systematic errors in the anemometers. Therefore, it is the measurements in the cavity which are inaccurate and not the calculations.

In this paper, a fuzzy-logic FAM (fuzzy associative memory) matrix classifier is used for the classification (diagnosis) of breast cancer. It is implemented in Mathematica 3.0 and tested on two features (radius and perimeter) from the Wisconsin breast cancer database. The sensitivity of the FAM-matrix classifier is 94.29%, and its specificity is 73.33%.

Like standard discrete artificial neural networks (ANNs), continual neurodynamical systems can be used for the classification and diagnosis of breast cancer. In this paper, a two-feature generalized bidirectional associative memory (GBAM) classifier is formulated in tensorial invariant form. It is implemented in Mathematica 3.0 and tested on two sample features (the radius and perimeter of cell nuclei in fine-needle aspiration slides) from the Wisconsin breast-cancer database. The classification accuracy obtained (86%), together with the invariance of the classification result upon the variation of the dimensions and output form of the neural activation fields, shows the potential classification ability of theoretical classifiers that are directly implemented in computer algebra systems.

This paper contains results on the design of optimum equalizers to eliminate intersymbol interference in linear non-minimum phase channels conveying binary signals. The optimization is with respect to an open eye condition with a given delay. For causal stable channels with non-minimum phase zeros, we argue that this problem requires only the consideration of the FIR modified channel that has all the non-minimum phase zeros of the original channel. We show that if this modified channel can be equalized to yield an equalized system that is open eye with a specified delay, then the optimizing equalizer is, in fact FIR with all zeros outside the unit circle, and the impulse response of the equalised channel does not extend beyond the delay. We also give a simple necessary and sufficient condition to determine if for a particular delay, a given channel can be equalized to achieve an equalized response that is open eye.

In children at high risk of inhalation allergy, food sensitization is associated with an increased risk for sensitization to inhalant allergens. Furthermore, this association was also found in a cross-sectional study.To examine in a prospective study, whether levels of IgG to foods (i.e. mixture of wheat and rice, mixture of soy bean and peanut, egg white, cow's milk, meat, orange and potato) indicate an increased risk for the future development of IgE antibodies to inhalant allergens in a low-risk population and whether they can be used as predictors of the subsequent development of IgE antibodies in young, initially IgE-negative children.Coughing children, aged 1-5, visiting their GPs, were tested for IgE antibodies to mite, dog and cat (RAST) and IgG (ELISA) to foods. All IgE-negative children were retested for IgE antibodies after two years. The IgG results (66 percentiles) of the first blood sample were compared to the RAST-scores of the second blood sample.After two years, 51 out of 397 (12.8%) originally IgE-negative children, had become IgE-positive for cat, dog and/or mite. An increased IgG antibody level to wheat-rice (OR = 2.2) and to orange (OR = 2.0) indicated an increased risk of developing IgE to cat, dog or mite allergens. In addition to IgG to a mixture of wheat-rice and orange; total IgE, breastfeeding, eczema as a baby and age were the most important predictors for the subsequent development of IgE to inhalant allergens.An increased IgG antibody level to a mixture of wheat-rice or orange, indicates an increased risk of developing IgE to cat, dog or mite allergens. This indicates that excessive activity of the mucosal immune system is present before IgE antibodies to airborne allergens can be demonstrated. Nevertheless, IgG to foods is not very helpful (with a positive predictive value of 16.5%, and negative predictive value of 90.6%) in identifying individual children at risk in clinical practice. However, besides other risk factors, IgG to wheat-rice and to orange could be useful as a screening test for studies in the early identification, i.e. before IgE antibodies can be detected, of children with an increased risk of developing IgE antibodies in the future.

The aim of this work is to present experimentally evaluated effective roughnesses (z(oe)) of a partly forested landscape. Although the ratio of boundary-layer height to obstacle size was only of the order of 50, there still seemed to exist a height range of 75-200 m where surface-layer similarity was approximately valid. Attempts were made to use conventional wind profile analysis to evaluate z(oe), but the small height range and the large number of variables initially led to unacceptable uncertainties. Fixing the displacement height z(d), rather than fitting it, reduced the data scatter to an acceptable level. The profile-derived roughness lengths z(op) obtained in this way were in good agreement with previous work, and with an alternative roughness length estimate z(of) for which flux-derived profile parameters u* and theta* were used. This implies that the profile-derived roughnesses were consistent with the measured surface-layer momentum flux. Comparison of both roughness estimates also yielded an improved estimate of the displacement height. Besides this, the authors tested a landscape roughness evaluation method which makes use of the gustiness parameter T-u = sigma(u)/U in the surface layer. The results obtained by this method were in fair agreement with the profile-derived data. In previous work, the gustiness method was advocated because it could be used at relatively low levels, perhaps even within the roughness sub-layer. At the present measuring Site, this was not the case as the gustiness method was only valid in an approximate way, and for a limited height range.

The Space Telescope Imaging Spectrograph (STIS) operates from the UV to near IR providing a general purpose, imaging spectroscopic capability. An internal, two mirror relay system corrects the spherical aberration and astigmatism present at the STIS field position. Low and medium resolution imaging spectroscopy is possible throughout the spectral range and over the 25 arcsecond UV and 52 arcsecond visible fields. High resolution echelle spectroscopy capability is also provided in the UV. Target acquisition is accomplished using the STIS cameras, either UV or visible; these cameras may also be used to provide broad band imaging over the complete spectral range or with the small selection of available bandpass filters. A wide selection of slits and apertures permit various combinations of spectral resolution and field size in all modes. On board calibration lamps provide wavelength calibration and flat fielding capability. We report here on the optical performance of STIS as determined during orbital verification.

The STIS instrument was installed into HST in February 1997 during the Servicing Mission 2. It has almost completed checkout and is beginning its science program, and is working well. Several scientific demonstration observations were taken to illustrate some of the range of scientific uses and modes of observation of STIS.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Some calibraton results of the K-Gill propeller vane are discussed. The propellers static and dynamic response were determined. The two propellers show perfect linearity in calibration factor. Starting speed is found less than 0.18 ms-1. Response lengths of the propellers is 2.5 m. effective response in K-Gill configuration is 3.3 m. A new function for propeller response to a drop to zero in wind speed is suggested.

Synopsis The accuracy of some setting methods applicable in two-beam interferometry is investigated with regard to its dependence on the conditions of observation. Photometric methods prove to be the most advantageous. With these, an accuracy of a few thousandths of a wavelength in one setting is attainable under favourable conditions.

Water vapor in the atmosphere of Venus was discovered in November 1959 by observations made at 80000-ft. altitude with a manned balloon-telescope system. This result was confirmed and measured far more precisely in February 1964 with an automatic unmanned system. The method of observing Venus water-vapor absorption in the 1.13-μ band, and the interpretation of that absorption, are described.

Temperature quenching causes a marked increase of the rate of decay of fluorescence. It is shown that both the efficiency of fluorescence and the decay are determined by the probabilities of the fluorescence transition and of a radiationless transition. By combining data from measurements of the efficiency and the decay, it is possible to obtain the two transition probabilities separately, and both as a function of the temperature. The results with (NH 4 ) 3 UO 2 F 5 and Mg 2 TiO 4 . Mn 4+ have been used to verify whether the radiationless process follows the theory of Mott and Seitz, or of Moglich and Rompe; they are found to favour the former.

On the basis of a simple model for diffraction by the groove, we show that the efficiency of an echelle is high in the Littrow arrangement, but becomes markedly less if the angle of deviation between the incident and the diffracted beams is increased. We also show that the height and width of the spectral image change if the directions of incidence and diffraction are interchanged, but that the efficiency remains the same. In general, the direction of maximum efficiency does not coincide with the blaze direction, defined as the maximum of the envelope of the diffracted-light distribution function. The difference depends on the mode of operation of the spectrograph (scanned or stationary spectrum) and typically changes from a fraction of a degree at high orders in the UV to several degrees at low orders in the IR. Experimental evidence agrees qualitatively with these calculations, but a more refined diffraction model may be needed for a quantitative interpretation.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A novel sounding rocket payload consisting of a slitless objective grating spectrograph with no transmission elements in the optical train (or detector) is described. This instrument, called the interstellar medium absorption profile spectrograph (IMAPS), is designed to provide continuous coverage over the wavelength range of 950-1150 A; it has an effective collecting area of about 4 sq cm and can record spectra of pointlike sources at a wavelength resolution of 0.004 A and with a sample interval of 0.002 A. The successful use of this instrument aboard a Black Brant rocket is described.

The High-Resolution Spectrograph (HRS) covers the 105 nm to 320 nm wavelength range at nominal spectral resolutions 103, 104 and 105. It employs one ruled, plane, first-order grating (600 grooves/mm), four holographic, plane, first-order gratings (3600, 4320, 4960 and 6000 grooves/mm), one r/2 echelle (316 grooves/mm) and two ruled, multi-partite, concave cross dispersers (88 and 198 grooves/mm). These gratings are all replicas. The absolute efficiencies of the first-order gratings were measured by the Goddard Space Flight Center (GSFC) before integration into the HRS. The spectral resolution was derived from line-width measurements in the Pt spectrum during pre-flight calibration of the complete instrument at the Ball Aerospace Systems Division (BASD). Relative scattered-light levels were determined from gaseous absorption spectra. In some of the holographic gratings spurious images were observed parallel to the spectra. In the echelle the effective blaze angle in the UV was derived from relative-efficiency measurements and found to be about 62.8°. The spectral resolution and the scattered-light background were measured by the same techniques as above. Ghosts were detected at 0.45 interorder distances. Their relative intensities are less than 0.1% at 150 nm.

The high resolution spectrograph (HRS) for ultraviolet astronomy with the Space Telescope will provide a spectral resolution of approximately 120,000 over a nominal wavelength range of 110-320 nm, together with a spatial resolution of about 0.25 arc seconds. The two detectors will consist of 512-element Digicons with cesium telluride and cesium iodide photocathodes, respectively. Photoelectrons in transit between the photocathodes and the diodes within the Digicons can be deflected in two axes with 12-bit resolution. This feature facilitates a design that emphasizes reliability since (once a hermetic seal is opened in orbit), only two moving parts, a grating carrousel and a shutter, are required for regular operation of the HRS. The instrument will be controlled by a computer in the spacecraft. The scientific objectives of the HRS investigation relate to interstellar matter in our own and nearby galaxies, physical processes of stellar mass loss and mass transfer, chemical abundances, bright quasars and Seyfert galaxy nuclei, and solar system phenomena.

The preliminary design for the Space Telescope Imaging Spectrograph (STIS), which has been selected by NASA for definition study for future flight as a second-generation instrument on the Hubble Space Telescope (HST), is presented. STIS is a two-dimensional spectrograph that will operate from 1050 A to 11,000 A at the limiting HST resolution of 0.05 arcsec FWHM, with spectral resolutions of 100, 1200, 20,000, and 100,000 and a maximum field-of-view of 50 x 50 arcsec. Its basic operating modes include echelle model, long slit mode, slitless spectrograph mode, coronographic spectroscopy, photon time-tagging, and direct imaging. Research objectives are active galactic nuclei, the intergalactic medium, global properties of galaxies, the origin of stellar systems, stelalr spectral variability, and spectrographic mapping of solar system processes.

SIRTF is a high-sensitivity, cooled astronomical telescope operating from 2 to 1000 microns. The techniques used in analyzing the sensitivity of the SIRTF system performance to several technical issues are presented. Lowering the telescope temperature to near 4K is found to produce margin in several areas. A refined observing requirements model relieves the hardware performance requirements, and identifies extended source size/observing strategy as an important system specification. Other major conclusions are presented.

Descriptions of a SISAM-interferometer for space application and of the performance of a Michelson type Fourier transform interferometer are given. The benefits and disadvantages of both instruments in different applications are discussed. The usable wavelength range for the SISAM ranges from 1 to 9 μ (extensible up to 100 μ). The Michelson interferometer is designed for the far infrared beyond 25 μ. The obtained spectral resolution is 0.2 cm−1 and 1 cm−1 respectively. Atmospheric effects on high resolution measurements from balloon or aircraft are discussed.

The interferometer consists of a beamsplitter and two spherical mirrors. Each mirror forms an image of the source on the detector. The transfer function is calculated for a point source and various detectors comparable in size to the diffraction images. The path difference is introduced by moving either one or both of the mirrors. For large detectors, the maximum-permitted path difference is twice the focal tolerance. For small detectors, the usable path difference is somewhat larger but depends on the manner in which the path difference is varied.

Far UV spectral intensity of B3 V star from Aerobee rocket scanning prism spectrometry, noting discrepancy with model atmosphere predictions