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The inner region of the Milky Way halo harbors a large amount of dark matter (DM). Given its proximity, it is one of the most promising targets to look for DM. We report on a search for the annihilations of DM particles using gamma-ray observations towards the inner 300 pc of the Milky Way, with the H.E.S.S. array of ground-based Cherenkov telescopes. The analysis is based on a 2D maximum likelihood method using Galactic Center (GC) data accumulated by H.E.S.S. over the last 10 years (2004-2014), and does not show any significant gamma-ray signal above background. Assuming Einasto and Navarro-Frenk-White DM density profiles at the GC, we derive upper limits on the annihilation cross section <sigma nu >. These constraints are the strongest obtained so far in the TeV DM mass range and improve upon previous limits by a factor 5. For the Einasto profile, the constraints reach <sigma nu > values of 6 x 10(-26) cm(3) s(-1) in the W+W- channel for a DM particle mass of 1.5 TeV, and 2 x 10(-26) cm(3) s(-1) in the tau(+)tau(-) channel for a 1 TeV mass. For the first time, ground-based gamma-ray observations have reached sufficient sensitivity to probe <sigma nu > values expected from the thermal relic density for TeV DM particles.
BACKGROUND: The Achilles tendon (AT) requires optimal material and mechanical properties to function properly. Calculation of these properties depends on accurate measurement of input parameters (i.e. tendon elongation). However, the measurement of AT elongation with ultrasound during maximum voluntary isometric contraction (MVIC) is overestimated by ankle joint rotation (AJR). Methods to correct the influence of this rotation on AT elongation exist, yet their reproducibility in clinical settings is unknown. OBJECTIVE: To evaluate the test-retest reproducibility of AT elongation during MVIC after AJR correction. METHODS: Ten participants attended test and retest measurements where they performed plantar-flexion MVIC on a dynamometer. Simultaneously, ultrasound recorded AT elongation as the displacement of the medial gastrocnemius-myotendinous junction, while an electrogoniometer measured AJR. The ankle was then passively rotated to the AJR achieved during MVIC and AT elongation again determined. Elongation was corrected by subtracting this passive AT elongation from the total AT elongation during MVIC. Reproducibility was evaluated using ICC (2.1), test-retest variability (TRV, %), Bland-Altman analyses (Bias +/- LoA [1.96*SD]) and standard error of the measurement (SEM). RESULTS: Corrected AT elongation reproducibility exhibited an ICC = 0.79, SEM = 0.2 cm and TRV = 20 +/- 19%. Bias +/- LoA were determined to be 0.0 +/- 0.8 cm. CONCLUSIONS: Using this ultrasound and electrogoniometer-based method, corrected AT elongation can be assessed reproducibly.
Eine verbesserte Zusammenarbeit und Abstimmung von Fachwissenschaft, Fachdidaktik, Bildungswissenschaften und schulpraktischen Lernorten ist einer der Förderbereiche der „Qualitätsoffensive Lehrerbildung“. Zahlreiche der geförderten Projekte haben für dieses Handlungsfeld im Bereich Vernetzung von Fachwissenschaft, Fachdidaktik und Bildungswissenschaften hochschulspezifische Maßnahmen konzipiert und umgesetzt.
Der vorliegende Tagungsband beinhaltet Beiträge von 15 entsprechenden Projekten, von denen sieben anlässlich von zwei standortübergreifenden Projekt-Tagungen in Hannover und Potsdam vorgestellt und in Workshops diskutiert wurden. Insgesamt geben die Beiträge einen theoretisch fundierten und gleichzeitig praxisorientierten Überblick über aktuelle Ansätze und Konzepte zur besseren Vernetzung fachwissenschaftlicher, fachdidaktischer und bildungswissenschaftlicher Studienanteile im Lehramtsstudium. Dargestellt werden Projektarbeiten der Hochschulen, die auf verschiedenen Ebenen wirksam werden (curricular-inhaltliche Ebene, kollegiale Ebene, hochschul-strukturelle Ebene). Die Maßnahmen sind so beschrieben, dass sie als Grundlage für einen Transfer auf andere Fächer bzw. andere Standorte genutzt werden können.
Die Beiträge richten sich an alle Lehrenden im Bereich der Lehramtsbildung sowie sonstige Akteure im Bereich der Lehr- und Qualitätsentwicklung an den Universitäten. Sie alle können den beschriebenen Konzepten und Umsetzungsformaten transferierbare Ideen und Impulse entnehmen.
Prevalence of Achilles tendinopathy increases with age leading to a weaker tendon with predisposition to rupture. Conclusive evidence of the influence of age and pathology on Achilles tendon (AT) properties remains limited, as previous studies are based on standardized isometric conditions. The study investigates the influence of age and pathology on AT properties during single-leg vertical jump (SLVJ). 10 children (C), 10 asymptomatic adults (A), and 10 tendinopathic patients (T) were included. AT elongation [mm] from rest to maximal displacement during a SLVJ on a force-plate was sonographically assessed. AT compliance [mm/N]) and strain [%] was calculated by dividing elongation by peak ground reaction force [N] and length, respectively. One-way ANOVA followed by Bonferroni post-hoc correction (=0.05) were used to compare C with A and A with T. AT elongation (p=0.004), compliance (p=0.001), and strain were found to be statistically significant higher in C (27 +/- 3mm, 0.026 +/- 0.006[mm/N], 13 +/- 2%) compared to A (21 +/- 4mm, 0.017 +/- 0.005[mm/N], 10 +/- 2%). No statistically significant differences (p0.05) was found between A and T (25 +/- 5mm, 0.019 +/- 0.004[mm/N], 12 +/- 3%). During SLVJ, tendon responded differently in regards to age and pathology with children having the most compliant AT. Higher compliance found in healthy tendons might be considered as a protective factor against load-related injuries.
The results of follow-up observations of the TeV gamma-ray source HESS J1640-465 from 2004 to 2011 with the High Energy Stereoscopic System (HESS) are reported in this work. The spectrum is well described by an exponential cut-off power law with photon index Gamma = 2.11 +/- 0.09(stat) +/- 0.10(sys), and a cut-off energy of E-2 = 6.0(-1.2)(+2.0) TeV. The TeV emission is significantly extended and overlaps with the northwestern part of the shell of the SNR G338.3-0.0. The new HESS results, a re-analysis of archival XMM-Newton data and multiwavelength observations suggest that a significant part of the gamma-ray emission from HESS J1640-465 originates in the supernova remnant shell. In a hadronic scenario, as suggested by the smooth connection of the GeV and TeV spectra, the product of total proton energy and mean target density could be as high as W(p)n(H) similar to 4 x 10(52)(d/10kpc)(2) erg cm(-3).
An annihilation signal of dark matter is searched for from the central region of the Milky Way. Data acquired in dedicated on-off observations of the Galactic center region with H.E.S.S. are analyzed for this purpose. No significant signal is found in a total of similar to 9 h of on-off observations. Upper limits on the velocity averaged cross section, <sigma upsilon >, for the annihilation of dark matter particles with masses in the range of similar to 300 GeV to similar to 10 TeV are derived. In contrast to previous constraints derived from observations of the Galactic center region, the constraints that are derived here apply also under the assumption of a central core of constant dark matter density around the center of the Galaxy. Values of <sigma upsilon > that are larger than 3 x 10(-24) cm(3)/s are excluded for dark matter particles with masses between similar to 1 and similar to 4 TeV at 95% C.L. if the radius of the central dark matter density core does not exceed 500 pc. This is the strongest constraint that is derived on <sigma upsilon > for annihilating TeV mass dark matter without the assumption of a centrally cusped dark matter density distribution in the search region.
Diffuse gamma-ray emission is the most prominent observable signature of celestial cosmic-ray interactions at high energies. While already being investigated at GeVenergies over several decades, assessments of diffuse gamma-ray emission at TeVenergies remain sparse. After completion of the systematic survey of the inner Galaxy, the H.E.S.S. experiment is in a prime position to observe large-scale diffuse emission at TeVenergies. Data of the H.E.S.S. Galactic Plane Survey are investigated in regions off known gamma-ray sources. Corresponding gamma-ray flux measurements were made over an extensive grid of celestial locations. Longitudinal and latitudinal profiles of the observed gamma-ray fluxes show characteristic excess emission not attributable to known gamma-ray sources. For the first time large-scale gamma-ray emission along the Galactic plane using imaging atmospheric Cherenkov telescopes has been observed. While the background subtraction technique limits the ability to recover modest variation on the scale of the H.E.S.S. field of view or larger, which is characteristic of the inverse Compton scatter-induced Galactic diffuse emission, contributions of neutral pion decay as well as emission from unresolved gamma-ray sources can be recovered in the observed signal to a large fraction. Calculations show that the minimum gamma-ray emission from pi(0) decay represents a significant contribution to the total signal. This detection is interpreted as a mix of diffuse Galactic gamma-ray emission and unresolved sources.
Context. Puppis A is an interesting similar to 4 kyr-old supernova remnant (SNR) that shows strong evidence of interaction between the forward shock and a molecular cloud. It has been studied in detail from radio frequencies to high-energy (HE, 0.1-100 GeV) gamma-rays. An analysis of the Fermi-LAT data has shown extended HE gamma-ray emission with a 0.2-100 GeV spectrum exhibiting no significant deviation from a power law, unlike most of the GeV-emitting SNRs known to be interacting with molecular clouds. This makes it a promising target for imaging atmospheric Cherenkov telescopes (IACTs) to probe the gamma-ray emission above 100 GeV.
Aims. Very-high-energy (VHE, E >= 0.1 TeV) gamma-ray emission from Puppis A has been, for the first time, searched for with the High Energy Stereoscopic System (HESS.).
Methods. Stereoscopic imaging of Cherenkov radiation from extensive air showers is used to reconstruct the direction and energy of the incident gamma-rays in order to produce sky images and source spectra. The profile likelihood method is applied to find constraints on the existence of a potential break or cutoff in the photon spectrum.
Results. The analysis of the HESS. data does not reveal any significant emission towards Puppis A. The derived upper limits on the differential photon flux imply that its broadband gamma-ray spectrum must exhibit a spectral break or cutoff. By combining Fermi-LAT and HESS. measurements, the 99% confidence-level upper limits on such a cutoff are found to be 450 and 280 GeV, assuming a power law with a simple exponential and a sub-exponential cutoff, respectively. It is concluded that none of the standard limitations (age, size, radiative losses) on the particle acceleration mechanism, assumed to be continuing at present, can explain the lack of VHE signal. The scenario in which particle acceleration has ceased some time ago is considered as an alternative explanation. The HE/VHE spectrum of Puppis A could then exhibit a break of non-radiative origin (as observed in several other interacting SNRs, albeit at somewhat higher energies), owing to the interaction with dense and neutral material, in particular towards the NE region.
A search for dark matter linelike signals iss performed in the vicinity of the Galactic Center by the H.E.S.S. experiment on observational data taken in 2014. An unbinned likelihood analysis iss developed to improve the sensitivity to linelike signals. The upgraded analysis along with newer data extend the energy coverage of the previous measurement down to 100 GeV. The 18 h of data collected with the H.E.S.S. array allow one to rule out at 95% C.L. the presence of a 130 GeV line (at l = -1.5 degrees, b = 0 degrees and for a dark matter profile centered at this location) previously reported in Fermi-LAT data. This new analysis overlaps significantly in energy with previous Fermi-LAT and H.E.S.S. results. No significant excess associated with dark matter annihilations was found in the energy range of 100 GeV to 2 TeV and upper limits on the gamma-ray flux and the velocity weighted annihilation cross section are derived adopting an Einasto dark matter halo profile. Expected limits for present and future large statistics H.E.S.S. observations are also given.
Das 3. Herbsttreffen Patholinguistik fand am 21. November 2009 an der Universität Potsdam statt. Der vorliegende Tagungsband enthält die drei Hauptvorträge zum Schwerpunktthema „Von der Programmierung zu Artikulation: Sprechapraxie bei Kindern und Erwachsenen“. Darüber hinaus enthält der Band die Beiträge aus dem Spektrum Patholinguistik, sowie die Abstracts der Posterpräsentationen.
This study aimed to build on the relationship of well-established self-report and behavioral assessments to the latent constructs positive (PVS) and negative valence systems (NVS), cognitive systems (CS), and social processes (SP) of the Research Domain Criteria (RDoC) framework in a large transnosological population which cuts across DSM/ICD-10 disorder criteria categories. One thousand four hundred and thirty one participants (42.1% suffering from anxiety/fear-related, 18.2% from depressive, 7.9% from schizophrenia spectrum, 7.5% from bipolar, 3.4% from autism spectrum, 2.2% from other disorders, 18.4% healthy controls, and 0.2% with no diagnosis specified) recruited in studies within the German research network for mental disorders for the Phenotypic, Diagnostic and Clinical Domain Assessment Network Germany (PD-CAN) were examined with a Mini-RDoC-Assessment including behavioral and self-report measures. The respective data was analyzed with confirmatory factor analysis (CFA) to delineate the underlying latent RDoC-structure. A revised four-factor model reflecting the core domains positive and negative valence systems as well as cognitive systems and social processes showed a good fit across this sample and showed significantly better fit compared to a one factor solution. The connections between the domains PVS, NVS and SP could be substantiated, indicating a universal latent structure spanning across known nosological entities. This study is the first to give an impression on the latent structure and intercorrelations between four core Research Domain Criteria in a transnosological sample. We emphasize the possibility of using already existing and well validated self-report and behavioral measurements to capture aspects of the latent structure informed by the RDoC matrix.
Study Design. A nonrandomized, prospective, and single-center clinical trial. Objective. The aim of this study was to investigate the clinical and radiographic efficacy of ProDisc Vivo cervical total disc replacement (cTDR) in patients with clinical and radiographic documented cervical spondylotic myelopathy (CSM), due to degenerative changes at the index level. Summary of Background Data. Decompression and fusion is still the gold standard in patients with cervical myelopathy. Very limited data are available regarding the application of cTDR in patients with clinical and radiological documented CSM in context of clinical and radiographic outcomes. Methods. Clinical outcome scores included the Neck Disability Index (NDI), Visual Analogue Scale (VAS), arm and neck pain self-assessment questionnaires as well as the Nurick grade and the Japanese Orthopaedic Association (JOA) score. The radiological outcome included the range of motion (ROM), the segmental and global (C2-C7) lordosis, and the occurrence of heterotopic ossifications. Results. Eighteen consecutive patients (10 males, 8 females) with documented clinical and radiological signs of myelopathy were included in this investigation. The study population had a mean age of 52.4 years and a follow-up period of 20.3 months in average (range 3-48 months). The mean range ROM of the index level stayed consistent with 6.8 degrees preoperatively and 7.2 degrees (P = 0.578) at the last follow-up; the global lordosis in neutral position changed from 3.5 degrees to 14.2 degrees significantly (P = 0.005) in mean. The JOA score improved from 11.3 to 16.6 (P < 0.001) as well as the NDI 36.7 to 10.3 (P < 0.001) and the VAS score from 5.7/6.1 (arm/neck) to 1.3/2.0 (P P < 0.001). The mean Nurick grade was 1.33 preoperatively and dropped down in all cases to Nurick grade of 0 (P < 0.001). Conclusion. cTDR (with ProDisc Vivio) in patients with CSM yielded good clinical and radiographic outcomes and found as a reliable, safe, and motion-preserving surgical treatment option, although its indication is very limited due to numerous exclusion criteria.
The genetic integrity of each organism depends on the faithful segregation of its genome during mitosis. To meet this challenge, a cellular surveillance mechanism, termed the spindle assembly checkpoint (SAC), evolved that monitors the correct attachment of chromosomes and blocks progression through mitosis if corrections are needed. While the central role of the SAC for genome integrity is well established, its functional dissection has been hampered by the limited availability of appropriate small molecule inhibitors. Using a fluorescence polarization-based screen, we identify Mad2 inhibitor-1 (M2I-1), the first small molecule inhibitor targeting the binding of Mad2 to Cdc20, an essential protein-protein interaction (PPI) within the SAC. Based on computational and biochemical analyses, we propose that M2I-1 disturbs conformational dynamics of Mad2 critical for complex formation with Cdc20. Cellular studies revealed that M2I-1 weakens the SAC response, indicating that the compound might be active in cells. Thus, our study identifies the SAC specific complex formation between Mad2 and Cdc20 as a protein-protein interaction that can be targeted by small molecules.
Sonographically detectable intratendinous blood flow (IBF) is found in 50%-88% of Achilles tendinopathy patients as well as in up to 35% of asymptomatic Achilles tendons (AT). Although IBF is frequently associated with tendon pathology, it may also represent a physiological regulation, for example, due to increased blood flow in response to exercise. Therefore, this study aimed to investigate the acute effects of a standardized running exercise protocol on IBF assessed with Doppler ultrasound (DU) Advanced dynamic flow in healthy ATs. 10 recreationally active adults (5 f, 5m; 29 +/- 3years, 1.72 +/- 0.12m, 68 +/- 16kg, physical activity 206 +/- 145minute/wk) with no history of AT pain and inconspicious tendon structure performed 3 treadmill running tasks on separate days (M1-3) with DU examinations directly before and 5, 30, 60, and 120minutes after exercise. At M1, an incremental exercise test was used to determine the individual anaerobic threshold (IAT). At M2 and M3, participants performed 30-minute submaximal constant load tests (CL1/CL2) with an intensity 5% below IAT. IBF in each tendon was quantified by counting the number of vessels. IBF increased in five ATs from no vessels at baseline to one to four vessels solely detectable 5minutes after CL1 or CL2. One AT had persisting IBF (three vessels) throughout all examinations. Fourteen ATs revealed no IBF at all. Prolonged running led to a physiological, temporary appearance of IBF in 25% of asymptomatic ATs. To avoid exercise-induced IBF in clinical practice, DU examinations should be performed after 30minutes of rest.
Calcularis is a computer-based training program which focuses on basic numerical skills, spatial representation of numbers and arithmetic operations. The program includes a user model allowing flexible adaptation to the child's individual knowledge and learning profile. The study design to evaluate the training comprises three conditions (Calcularis group, waiting control group, spelling training group). One hundred and thirty-eight children from second to fifth grade participated in the study. Training duration comprised a minimum of 24 training sessions of 20 min within a time period of 6-8 weeks. Compared to the group without training (waiting control group) and the group with an alternative training (spelling training group), the children of the Calcularis group demonstrated a higher benefit in subtraction and number line estimation with medium to large effect sizes. Therefore, Calcularis can be used effectively to support children in arithmetic performance and spatial number representation.
Calcularis is a computer-based training program which focuses on basic numerical skills, spatial representation of numbers and arithmetic operations. The program includes a user model allowing flexible adaptation to the child's individual knowledge and learning profile. The study design to evaluate the training comprises three conditions (Calcularis group, waiting control group, spelling training group). One hundred and thirty-eight children from second to fifth grade participated in the study. Training duration comprised a minimum of 24 training sessions of 20 min within a time period of 6–8 weeks. Compared to the group without training (waiting control group) and the group with an alternative training (spelling training group), the children of the Calcularis group demonstrated a higher benefit in subtraction and number line estimation with medium to large effect sizes. Therefore, Calcularis can be used effectively to support children in arithmetic performance and spatial number representation.
The amyloid precursor protein (APP) and its paralogs, amyloid precursor-like protein 1 (APLP1) and APLP2, are metalloproteins with a putative role both in synaptogenesis and in maintaining synapse structure. Here, we studied the effect of zinc on membrane localization, adhesion, and secretase cleavage of APP, APLP1, and APLP2 in cell culture and rat neurons. For this, we employed live-cell microscopy techniques, a microcontact printing adhesion assay and ELISA for protein detection in cell culture supernatants. We report that zinc induces the multimerization of proteins of the amyloid precursor protein family and enriches them at cellular adhesion sites. Thus, zinc facilitates the formation of de novo APP and APLP1 containing adhesion complexes, whereas it does not have such influence on APLP2. Furthermore, zinc-binding prevented cleavage of APP and APLPs by extracellular secretases. In conclusion, the complexation of zinc modulates neuronal functions of APP and APLPs by (i) regulating formation of adhesion complexes, most prominently for APLP1, and (ii) by reducing the concentrations of neurotrophic soluble APP/APLP ectodomains.
Magmatism forming the Central Anatolian Volcanic Province of Cappadocia, central Turkey, records the last phase of Neotethyan subduction after similar to 11 Ma. Thirteen large calc-alkaline ignimbrite sheets form marker bands within the volcano-sedimentary succession (the Urgup Formation) and provide a robust chronostratigraphy for paleoecologic evaluation of the interleaved paleosols. This paper evaluates the chronologic record in the context of the radiometric, magnetostratigraphic and lithostratigraphic controls. Previous inconsistencies relating primarily to K/Ar evidence were reason for the initiation of an integrated study which includes Ar-40/Ar-39 dating, palaeomagnetic and stratigraphic evidence. The newly determined Ar-40/Ar-39-ages (Lepetit, 2010) are in agreement with Ar/Ar and U/Pb data meanwhile published by Pauquette and Le Pennec (2012) and Aydar et al. (2012). The Ar-40/Ar-39-ages restrict the end of the Urgup Formation to the late Miocene. The paleosol sequence enclosed by the ignimbrites is thus restricted to the late Miocene, the most intense formation of pedogene calcretes correlating with the Messinian Salinity Crisis.
Pulsar wind nebulae (PWNe) are the most abundant TeV gamma-ray emitters in the Milky Way. The radiative emission of these objects is powered by fast-rotating pulsars, which donate parts of their rotational energy into winds of relativistic particles. This thesis presents an in-depth study of the detected population of PWNe at high energies. To outline general trends regarding their evolutionary behaviour, a time-dependent model is introduced and compared to the available data. In particular, this work presents two exceptional PWNe which protrude from the rest of the population, namely the Crab Nebula and N 157B. Both objects are driven by pulsars with extremely high rotational energy loss rates. Accordingly, they are often referred to as energetic twins. Modelling the non-thermal multi-wavelength emission of N157B gives access to specific properties of this object, like the magnetic field inside the nebula. Comparing the derived parameters to those of the Crab Nebula reveals large intrinsic differences between the two PWNe. Possible origins of these differences are discussed in context of the resembling pulsars.
Compared to the TeV gamma-ray regime, the number of detected PWNe is much smaller in the MeV-GeV gamma-ray range. In the latter range, the Crab Nebula stands out by the recent detection of gamma-ray flares. In general, the measured flux enhancements on short time scales of days to weeks were not expected in the theoretical understanding of PWNe. In this thesis, the variability of the Crab Nebula is analysed using data from the Fermi Large Area Telescope (Fermi-LAT). For the presented analysis, a new gamma-ray reconstruction method is used, providing a higher sensitivity and a lower energy threshold compared to previous analyses. The derived gamma-ray light curve of the Crab Nebula is investigated for flares and periodicity. The detected flares are analysed regarding their energy spectra, and their variety and commonalities are discussed. In addition, a dedicated analysis of the flare which occurred in March 2013 is performed. The derived short-term variability time scale is roughly 6h, implying a small region inside the Crab Nebula to be responsible for the enigmatic flares. The most promising theories explaining the origins of the flux eruptions and gamma-ray variability are discussed in detail.
In the technical part of this work, a new analysis framework is presented. The introduced software, called gammalib/ctools, is currently being developed for the future CTA observa- tory. The analysis framework is extensively tested using data from the H. E. S. S. experiment. To conduct proper data analysis in the likelihood framework of gammalib/ctools, a model describing the distribution of background events in H.E.S.S. data is presented. The software provides the infrastructure to combine data from several instruments in one analysis. To study the gamma-ray emitting PWN population, data from Fermi-LAT and H. E. S. S. are combined in the likelihood framework of gammalib/ctools. In particular, the spectral peak, which usually lies in the overlap energy regime between these two instruments, is determined with the presented analysis framework. The derived measurements are compared to the predictions from the time-dependent model. The combined analysis supports the conclusion of a diverse population of gamma-ray emitting PWNe.