146 resultados para SLR


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Satellite laser ranging (SLR) to the satellites of the global navigation satellite systems (GNSS) provides substantial and valuable information about the accuracy and quality of GNSS orbits and allows for the SLR-GNSS co-location in space. In the framework of the NAVSTAR-SLR experiment two GPS satellites of Block-IIA were equipped with laser retroreflector arrays (LRAs), whereas all satellites of the GLONASS system are equipped with LRAs in an operational mode. We summarize the outcome of the NAVSTAR-SLR experiment by processing 20 years of SLR observations to GPS and 12 years of SLR observations to GLONASS satellites using the reprocessed microwave orbits provided by the center for orbit determination in Europe (CODE). The dependency of the SLR residuals on the size, shape, and number of corner cubes in LRAs is studied. We show that the mean SLR residuals and the RMS of residuals depend on the coating of the LRAs and the block or type of GNSS satellites. The SLR mean residuals are also a function of the equipment used at SLR stations including the single-photon and multi-photon detection modes. We also show that the SLR observations to GNSS satellites are important to validate GNSS orbits and to assess deficiencies in the solar radiation pressure models. We found that the satellite signature effect, which is defined as a spread of optical pulse signals due to reflection from multiple reflectors, causes the variations of mean SLR residuals of up to 15 mm between the observations at nadir angles of 0∘ and 14∘. in case of multi-photon SLR stations. For single-photon SLR stations this effect does not exceed 1 mm. When using the new empirical CODE orbit model (ECOM), the SLR mean residual falls into the range 0.1–1.8 mm for high-performing single-photon SLR stations observing GLONASS-M satellites with uncoated corner cubes. For best-performing multi-photon stations the mean SLR residuals are between −12.2 and −25.6 mm due to the satellite signature effect.

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The population of space debris increased drastically during the last years. These objects have become a great threat for active satellites. Because the relative velocities between space debris and satellites are high, space debris objects may destroy active satellites through collisions. Furthermore, collisions involving massive objects produce large number of fragments leading to significant growth of the space debris population. The long term evolution of the debris population is essentially driven by so-called catastrophic collisions. An effective remediation measure in order to stabilize the population in Low Earth Orbit (LEO) is therefore the removal of large, massive space debris. To remove these objects, not only precise orbits, but also more detailed information about their attitude states will be required. One important property of an object targeted for removal is its spin period, spin axis orientation and their change over time. Rotating objects will produce periodic brightness variations with frequencies which are related to the spin periods. Such a brightness variation over time is called a light curve. Collecting, but also processing light curves is challenging due to several reasons. Light curves may be undersampled, low frequency components due to phase angle and atmospheric extinction changes may be present, and beat frequencies may occur when the rotation period is close to a multiple of the sampling period. Depending on the method which is used to extract the frequencies, also method-specific properties have to be taken into account. The astronomical Institute of the University of Bern (AIUB) light curve database will be introduced, which contains more than 1,300 light curves acquired over more than seven years. We will discuss properties and reliability of different time series analysis methods tested and currently used by AIUB for the light curve processing. Extracted frequencies and reconstructed phases for some interesting targets, e.g. GLONASS satellites, for which also SLR data were available for the period confirmation, will be presented. Finally we will present the reconstructed phase and its evolution over time of a High-Area-to-Mass-Ratio (HAMR) object, which AIUB observed for several years.

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Today, there is little knowledge on the attitude state of decommissioned intact objects in Earth orbit. Observational means have advanced in the past years, but are still limited with respect to an accurate estimate of motion vector orientations and magnitude. Especially for the preparation of Active Debris Removal (ADR) missions as planned by ESA’s Clean Space initiative or contingency scenarios for ESA spacecraft like ENVISAT, such knowledge is needed. ESA's “Debris Attitude Motion Measurements and Modelling” project (ESA Contract No. 40000112447), led by the Astronomical Institute of the University of Bern (AIUB), addresses this problem. The goal of the project is to achieve a good understanding of the attitude evolution and the considerable internal and external effects which occur. To characterize the attitude state of selected targets in LEO and GTO, multiple observation methods are combined. Optical observations are carried out by AIUB, Satellite Laser Ranging (SLR) is performed by the Space Research Institute of the Austrian Academy of Sciences (IWF) and radar measurements and signal level determination are provided by the Fraunhofer Institute for High Frequency Physics and Radar Techniques (FHR). The In-Orbit Tumbling Analysis tool (ιOTA) is a prototype software, currently in development by Hyperschall Technologie Göttingen GmbH (HTG) within the framework of the project. ιOTA will be a highly modular software tool to perform short-(days), medium-(months) and long-term (years) propagation of the orbit and attitude motion (six degrees-of-freedom) of spacecraft in Earth orbit. The simulation takes into account all relevant acting forces and torques, including aerodynamic drag, solar radiation pressure, gravitational influences of Earth, Sun and Moon, eddy current damping, impulse and momentum transfer from space debris or micro meteoroid impact, as well as the optional definition of particular spacecraft specific influences like tank sloshing, reaction wheel behaviour, magnetic torquer activity and thruster firing. The purpose of ιOTA is to provide high accuracy short-term simulations to support observers and potential ADR missions, as well as medium-and long-term simulations to study the significance of the particular internal and external influences on the attitude, especially damping factors and momentum transfer. The simulation will also enable the investigation of the altitude dependency of the particular external influences. ιOTA's post-processing modules will generate synthetic measurements for observers and for software validation. The validation of the software will be done by cross-calibration with observations and measurements acquired by the project partners.

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The population of space debris increased drastically during the last years. Collisions involving massive objects may produce large number of fragments leading to significantly growth of the space debris population. An effective remediation measure in order to stabilize the population in LEO, is therefore the removal of large, massive space debris. To remove these objects, not only precise orbits, but also more detailed information about their attitude states will be required. One important property of an object targeted for removal is its spin period and spin axis orientation. If we observe a rotating object, the observer sees different surface areas of the object which leads to changes in the measured intensity. Rotating objects will produce periodic brightness vari ations with frequencies which are related to the spin periods. Photometric monitoring is the real tool for remote diagnostics of the satellite rotation around its center of mass. This information is also useful, for example, in case of contingency. Moreover, it is also important to take into account the orientation of non-spherical body (e.g. space debris) in the numerical integration of its motion when a close approach with the another spacecr aft is predicted. We introduce the two databases of light curves: the AIUB data base, which contains about a thousand light curves of LEO, MEO and high-altitude debris objects (including a few functional objects) obtained over more than seven years, and the data base of the Astronomical Observatory of Odessa University (Ukraine), which contains the results of more than 10 years of photometric monitoring of functioning satellites and large space debris objects in low Earth orbit. AIUB used its 1m ZIMLAT telescope for all light curves. For tracking low-orbit satellites, the Astronomical Observatory of Odessa used the KT-50 telescope, which has an alt-azimuth mount and allows tracking objects moving at a high angular velocity. The diameter of the KT-50 main mirror is 0.5 m, and the focal length is 3 m. The Odessa's Atlas of light curves includes almost 5,5 thousand light curves for ~500 correlated objects from a time period of 2005-2014. The processing of light curves and the determination of the rotation period in the inertial frame is challenging. Extracted frequencies and reconstructed phases for some interesting targets, e.g. GLONASS satellites, for which also SLR data were available for confirmation, will be presented. The rotation of the Envisat satellite after its sudden failure will be analyzed. The deceleration of its rotation rate within 3 years is studied together with the attempt to determine the orientation of the rotation axis.

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The Center for Orbit Determination in Europe (CODE) is contributing as a global Analysis center to the International GNSS Service (IGS) since many years. The processing of GPS and GLONASS data is well established in CODE’s ultra-rapid, rapid, and final product lines. With the introduction of new signals for the established and new GNSS, new challenges and opportunities are arising for the GNSS data management and processing. The IGS started the Multi-GNSS-EXperiment (MGEX) in 2012 in order to gain first experience with the new data formats and to develop new strategies for making optimal use of these additional measurements. CODE has started to contribute to IGS MGEX with a consistent, rigorously combined triple-system orbit solution (GPS, GLONASS, and Galileo). SLR residuals for the computed Galileo satellite orbits are of the order of 10 cm. Furthermore CODE established a GPS and Galileo clock solution. A quality assessment shows that these experimental orbit and clock products allow even a Galileo-only precise point positioning (PPP) with accuracies on the decimeter- (static PPP) to meter-level (kinematic PPP) for selected stations.

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Coastal managers require reliable spatial data on the extent and timing of potential coastal inundation, particularly in a changing climate. Most sea level rise (SLR) vulnerability assessments are undertaken using the easily implemented bathtub approach, where areas adjacent to the sea and below a given elevation are mapped using a deterministic line dividing potentially inundated from dry areas. This method only requires elevation data usually in the form of a digital elevation model (DEM). However, inherent errors in the DEM and spatial analysis of the bathtub model propagate into the inundation mapping. The aim of this study was to assess the impacts of spatially variable and spatially correlated elevation errors in high-spatial resolution DEMs for mapping coastal inundation. Elevation errors were best modelled using regression-kriging. This geostatistical model takes the spatial correlation in elevation errors into account, which has a significant impact on analyses that include spatial interactions, such as inundation modelling. The spatial variability of elevation errors was partially explained by land cover and terrain variables. Elevation errors were simulated using sequential Gaussian simulation, a Monte Carlo probabilistic approach. 1,000 error simulations were added to the original DEM and reclassified using a hydrologically correct bathtub method. The probability of inundation to a scenario combining a 1 in 100 year storm event over a 1 m SLR was calculated by counting the proportion of times from the 1,000 simulations that a location was inundated. This probabilistic approach can be used in a risk-aversive decision making process by planning for scenarios with different probabilities of occurrence. For example, results showed that when considering a 1% probability exceedance, the inundated area was approximately 11% larger than mapped using the deterministic bathtub approach. The probabilistic approach provides visually intuitive maps that convey uncertainties inherent to spatial data and analysis.

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The DTRF2008 is a realization of the International Terrestrial Reference System ITRS. The DTRF2008 consists of station positions and velocities of global distributed observing stations of the space geodetic observation techniques VLBI, SLR, GPS and DORIS. The DTRF2008 was released in May 2010 and includes the observation data of the techniques up to and including 2008. The observation data are processed and submitted by the corresponding international services: IGS (International GNSS Service, http://igscb.jpl.nasa.gov) IVS (International VLBI Service, http://ivscc.gsfc.nasa.gov) ILRS (International Laser Ranging Service, http://ilrs.gsfc.nasa.gov) IDS (International DORIS Service, http://ids-doris.org). The DTRF2008 is an independent ITRS realization, which is computed on the basis of the same input data as the ITRF2008 (IGN, Paris). Both realizations differ with respect to their computation strategies: while the ITRF2008 is based on the combination of solutions, the DTRF2008 is computed by the combination of normal equations. The DTRF2008 comprises the coordinates of 559 GPS-, 106 VLBI-, 122 SLR- and 132 DORIS-stations. The reference epoch is 1.1.2005, 0h UTC. The Earth Orientation Parameters (EOP) - that means the coordinates of the terrestrial and the celestial pole, UT1-UTC and the Length of Day (LOD) - were simultaneously estimated with the station coordinates. The EOP time series cover the period of 1983 to 2008. The station names are the official IERS indications: cdp numbers or 4-character IDs and DOMES numbers (http://itrf.ensg.ign.fr/doc_ITRF/iers_sta_list.txt). The solution is available in different file formats (SINEX and SSC), see below. A detailed description of the solution is given by Seitz M. et al. (2012). The results of a comparison of DTRF2008 and ITRF2008 is given by Seitz M. et al. (2013). More information as well as residual time series of the station positions can be made available by request.

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The goal of our study is to determine accurate time series of geophysical Earth rotation excitations to learn more about global dynamic processes in the Earth system. For this purpose, we developed an adjustment model which allows to combine precise observations from space geodetic observation systems, such as Satellite Laser Ranging (SLR), Global Navigation Satellite Systems (GNSS), Very Long Baseline Interferometry (VLBI), Doppler Orbit determination and Radiopositioning Integrated on Satellite (DORIS), satellite altimetry and satellite gravimetry in order to separate geophysical excitation mechanisms of Earth rotation. Three polar motion time series are applied to derive the polar motion excitation functions (integral effect). Furthermore we use five time variable gravity field solutions from Gravity Recovery and Climate Experiment (GRACE) to determine not only the integral mass effect but also the oceanic and hydrological mass effects by applying suitable filter techniques and a land-ocean mask. For comparison the integral mass effect is also derived from degree 2 potential coefficients that are estimated from SLR observations. The oceanic mass effect is also determined from sea level anomalies observed by satellite altimetry by reducing the steric sea level anomalies derived from temperature and salinity fields of the oceans. Due to the combination of all geodetic estimated excitations the weaknesses of the individual processing strategies can be reduced and the technique-specific strengths can be accounted for. The formal errors of the adjusted geodetic solutions are smaller than the RMS differences of the geophysical model solutions. The improved excitation time series can be used to improve the geophysical modeling.

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The term cryosphere is used to refer to all portions of the Earth surface where water appears in solid form. This includes the snow cover; sea, lake and river ice; glaciers, ice caps and ice sheets; and permafrost. The aim of this contribution is to present the current state of the cryosphere. Emphasis will be given to sea ice and continental ice masses (glaciers, ice caps and ice sheets), and the contribution of the losses from the latter to sea level rise (SLR).

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During the last century many researches on the business, marketing and technology fields have developed the innovation research line and large amount of knowledge can be found in the literature. Currently, the importance of systematic and openness approaches to manage the available innovation sources is well established in many knowledge fields. Also in the software engineering sector, where the organizations need to absorb and to exploit as much innovative ideas as possible to get success in the current competitive environment. This Master Thesis presents an study related with the innovation sources in the software engineering eld. The main research goals of this work are the identication and the relevance assessment of the available innovation sources and the understanding of the trends on the innovation sources usage. Firstly, a general review of the literature have been conducted in order to define the research area and to identify research gaps. Secondly, the Systematic Literature Review (SLR) has been proposed as the research method in this work to report reliable conclusions collecting systematically quality evidences about the innovation sources in software engineering field. This contribution provides resources, built-on empirical studies included in the SLR, to support a systematic identication and an adequate exploitation of the innovation sources most suitable in the software engineering field. Several artefacts such as lists, taxonomies and relevance assessments of the innovation sources most suitable for software engineering have been built, and their usage trends in the last decades and their particularities on some countries and knowledge fields, especially on the software engineering, have been researched. This work can facilitate to researchers, managers and practitioners of innovative software organizations the systematization of critical activities on innovation processes like the identication and exploitation of the most suitable opportunities. Innovation researchers can use the results of this work to conduct research studies involving the innovation sources research area. Whereas, organization managers and software practitioners can use the provided outcomes in a systematic way to improve their innovation capability, increasing consequently the value creation in the processes that they run to provide products and services useful to their environment. In summary, this Master Thesis research the innovation sources in the software engineering field, providing useful resources to support an effective innovation sources management. Moreover, several aspects should be deeply study to increase the accuracy of the presented results and to obtain more resources built-on empirical knowledge. It can be supported by the INno- vation SOurces MAnagement (InSoMa) framework, which is introduced in this work in order to encourage openness and systematic approaches to identify and to exploit the innovation sources in the software engineering field.

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Objectives: Cognitive-behavioral pain management programs typically achieve improvements in pain cognitions, disability, and physical performance. However, it is not known whether the neurophysiology education component of such programs contributes to these outcomes. In chronic low back pain patients, we investigated the effect of neurophysiology education on cognitions, disability, and physical performance. Methods: This study was a blinded randomized controlled trial. Individual education sessions on neurophysiology of pain (experimental group) and back anatomy and physiology (control group) were conducted by trained physical therapist educators. Cognitions were evaluated using the Survey of Pain Attitudes (revised) (SOPA(R)), and the Pain Catastrophizing Scale (PCS). Behavioral measures included the Roland Morris Disability Questionnaire (RMDQ), and 3 physical performance tasks; (1) straight leg raise (SLR), (2) forward bending range, and (3) an abdominal drawing-in task, which provides a measure of voluntary activation of the deep abdominal muscles. Methodological checks evaluated non-specific effects of intervention. Results: There was a significant treatment effect on the SOPA(R), PCS, SLR, and forward bending. There was a statistically significant effect on RMDQ; however, the size of this effect was small and probably not clinically meaningful. Discussion: Education about pain neurophysiology changes pain cognitions and physical performance but is insufficient by itself to obtain a change in perceived disability. The results suggest that pain neurophysiology education, but not back school type education, should be included in a wider pain management approach.

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Neurodynamic tests such as the straight leg raising (SLR) and slump test are frequently used for assessment of mechanosensitivity of neural tissues. However, there is ongoing debate in the literature regarding the contributions of neural and non-neural tissues to the elicited symptoms because many structures are affected by these tests. Sensitizing manoeuvres are limb or spinal movements added to neurodynamic tests, which aim to identify the origin of the symptoms by preferentially loading or unloading neural structures. A prerequisite for the use of sensitizing manoeuvres to identify neural involvement is that the addition of sensitizing manoeuvres has no impact on pain perception when the origin of the pain is non-neural. In this study, experimental muscle pain was induced by injection of hypertonic saline in tibialis anterior or soleus in 25 asymptomatic, naive volunteers. A first experiment investigated the impact of hip adduction, abduction, medial and lateral rotation in the SLR position. In a second experiment, the different stages of the slump test were examined. The intensity and area of experimentally induced muscle pain did not increase when sensitizing manoeuvres were added to the SLR or throughout the successive stages of the slump test. The findings of this study lend support to the validity of the use of sensitizing manoeuvres during neurodynamic testing. (C) 2004 Elsevier Ltd. All rights reserved.

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A modified straight leg raising (SLR) in which ankle dorsiflexion is performed before hip flexion has been suggested to diagnose distal neuropathies such as tarsal tunnel syndrome. This study evaluates the clinical hypothesis that strain in the nerves around the ankle and foot caused by ankle dorsiflexion can be further increased with hip flexion. Linear displacement transducers were inserted into the sciatic, tibial, and plantar nerves and plantar fascia of eight embalmed cadavers to measure strain during the modified SLR. Nerve excursion was measured with a digital calliper. Ankle dorsiflexion resulted in a significant strain and distal. excursion of the tibial nerve. With the ankle in dorsiflexion, the proximal excursion and tension increase in the sciatic nerve associated with hip flexion were transmitted distally along the nerve from the hip to beyond the ankle. As hip flexion had an impact on the nerves around the ankle and foot but not on the plantar fascia, the modified SLR may be a useful test to differentially diagnose plantar heel pain. Although the modified SLR caused the greatest increase in nerve strain nearest the moving joint, mechanical forces acting on peripheral nerves are transmitted well beyond the moving joint. (c) 2006 Orthopaedic Research Society.

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Publicerad 16 maj, 2012 - 11:19 Att många religiösa ledare i moskéer ger uttryck för kvinnoförtryckande idéer innebär inte att alla gör det. I min undersökning ingår kvinnors berättelser om hur de i moskén erbjudits just det som samhället borde garantera, nämligen skyddat boende och stöd för dem som vill komma bort från ett våldspräglat hem, skriver Pia Karlsson Minganti. Kvinnor som vänder sig till rådgivare i moskéer kan få ta emot direktiv som är präglade av manscentrering och rent kvinnohat. Kvällens Uppdrag granskning visar exempel på detta. Utan att själv ha haft möjlighet att se programmet i sin helhet kan jag förutse starka reaktioner och krav på åtgärder. Jag arbetar själv mot könsförtryck, anser att våld och tvång ska polisanmälas och att redan existerande lagstiftning bör tillämpas. Med utgångspunkt i min egen forskning bland medlemmar i muslimska ungdomsföreningar i Sverige tror jag emellertid att debatten nu kan tjäna på att jag bidrar med perspektiv på moskéer som mer än endast arenor för misogyni. Insikten om att kategorin muslim samlar en miljard människor med alla tänkbara ideologiska orienteringar borde idag vara en självklarhet. På samma sätt är muslimska församlingar präglade av variation. Att många (just nu de flesta?) religiösa ledare i moskéer ger uttryck för kvinnoförtryckande idéer innebär inte att alla gör det. Inte heller innebär det att imamerna ifråga har kvinnoförtryck som uttalad målsättning eller aldrig verkar för kvinnors rättigheter. Verkligheten är som bekant komplex. En viktig poäng i sammanhanget är att islamiska rådgivare allt oftare är kvinnor. Internationell forskning visar på en samtida trend där kvinnor etablerar auktoritet i moskéer och organisationer, och virtuellt på internet. Det sker på eget initiativ, men även genom uppmuntran från manliga företrädare och genom statliga initiativ. De flesta bidrar som volontärer, som till exempel de ungdomsledare som runt om i Sverige engagerar ungdomar i allt från islamstudier till läxhjälp och alternativa helgaktiviteter på behörigt avstånd från alkohol och droger. Inom sina föreningar fungerar kvinnorna som beslutsfattare och organisatörer, som styrelseledamöter och ordföranden. De deltar också i andra offentliga sammanhang som föredragshållare och debattörer och samarbetspartners i olika projekt. Många av dessa projekt har till syfte att motverka diskriminering på grundval av kön, hudfärg och religiös tro. Kvinnornas religiösa engagemang kan liknas vid den kristna väckelserörelsen. Kvinnor, ungdomar och andra marginaliserade grupper sluter sig samman och studerar Koranen utan direkt inblandning av konventionella auktoriteter. De islamiska källorna används för att genomdriva förändringar och för att försvara bland annat kvinnors rättigheter. För många framstår våld mot kvinnor som en absurditet, helt oförenlig med islam. Vad jag försöker frammana här är en kontext där kvinnor kan instrueras att inte polisanmäla en misshandlande make, men där samtidigt andra typer av råd ges av olika tongivande personer och även hjälp att fly ut ur akuta våldssituationer. I min undersökning ingår kvinnors berättelser om hur medlemmar i moskéförsamlingar har erbjudit just det som samhället borde garantera, nämligen skyddat boende och stöd för dem som vill komma bort från ett våldspräglat hem. Det är bra att media granskar representanter i moskéer. Kritik kan bidra positivt till utvecklingen av islam i Sverige och motverka att män med destruktiv syn på könsrelationer fortsätter att dominera. Men det är viktigt att kritiken inte är ensidig eller fragmentarisk. När kvinnoförtryck såsom nedtystat våld och sexuellt tvång bland muslimer debatteras är även en annan form av förtryck närvarande: förtrycket mot muslimer som grupp. Det finns en tendens i dagens samhälle att peka ut muslimer som ett exceptionellt hot – mot kvinnor, homosexuella, judar, ”vanligt folk” och samhället i stort. Stigmatisering får flera olyckliga konsekvenser. För det första riskerar kvinnoförtryck i andra sammanhang att osynliggöras. I vilka andra miljöer borde tevereportage med dold kamera göras för att blotta de tänkesätt som leder till kvinnors lidande och död? Det är naturligtvis provocerande i sammanhanget, men erinra etnologen Jesper Fundbergs forskning om hur pojkfotboll fostrar unga i en miljö som knappast har gjort upp med sin sexism, rasism och homofobi. När gav den muslimkritiske debattören senast sitt stöd till en kvinnojour, med ett erkännande ord, praktiskt handtag eller rentav ekonomiskt bidrag? För det andra, politiska entreprenörer i islamofobi slår mynt av att muslimer pekas ut som det primära hotet. Sverigedemokrater hörs plötsligt försvara kvinnors, homosexuellas och judars rättigheter med hjälp av feministiska och antirasistiska argument med udden riktad mot muslimer och islam. För det tredje visar forskning på en tendens bland kvinnor i utsatta minoriteter att sluta upp bakom mansdominerade ledarskikt i syfte att värna gruppens väl, även om de samtidigt är kritiska mot dessa mäns tolkningar och praktiker. Att ensidigt förknippa islam med fenomen som våld mot kvinnor kan alltså få starkt negativa konsekvenser för prioriteringen av muslimska kvinnors välfärd. Våren 2010 debatterades riksorganisationen Sveriges Unga Muslimers val av gästföreläsare till sin årliga konferens. Den tänkta gästen förknippades med homofoba yttranden och debatten resulterade i att Ungdomsstyrelsen granskade ett antal bidragsberättigade religiösa ungdomsorganisationer för eventuell diskriminering mot homosexuella. Förutom Sveriges Unga Muslimer prövades även Ungdomsinitiativet inom Syrisk-ortodoxa ärkestiftet, Riksförbundet unga katoliker, Evangeliska frikyrkans och Pingstkyrkans ungdomssektioner. Granskningen av gruppernas formella handlingar gav inga skäl till att dra tillbaka deras statsbidrag och ingen fördjupad kontroll av enskilda medlemmars uttalanden gjordes. Exemplet visar att omfattningen av statlig granskning vägs mot människors grundlagsstadgade rättighet att organisera sig efter egna intressen och behov. Enskilda förgrundsgestalter är inte synonyma med sina samfund. I samma anda menar jag att tilltro till muslimers, kvinnor inräknade, förmåga att debattera, förhandla, tänja på och motstå förtryck gör det rimligt att framhålla muslimska församlingar och föreningar, inte bara som arenor för misogyni, utan även som plattformar för aktivt medborgande. En sådan tilltro bottnar också i insikten att det är möjligt att förändra de mest seglivade normer. Det visar inte minst den kriminalisering av våldtäkt inom äktenskapet som till slut skedde i Sverige 1965. Pia Karlsson Minganti, doktor och forskare i etnolog, Stockholms universitet