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PURPOSE High-density EEG (HD-EEG) systems and electrical source imaging techniques have revolutionized our ability to assess the potential sources of epileptiform activity and other EEG features. Nonetheless, clinical use of HD-EEG is hampered by the lack of a standardized electrode nomenclature system and the inherent difficulties encountered in visually reviewing recordings. Inefficient visual review of HD-EEG remains a major barrier to incorporating these techniques into routine clinical care. METHODS Extension of the 10-10 is first defined by the addition of 2 reference curves: the -10% and -20% axial reference curves. Electrode positions over the face are named based on facial bony structures (N = nasion, Z = zygomatic prominence, M = mandible) and over the back of the head on posterior landmarks (I = inion, S = subinion, B = Base). Then, following the 10% incremental distance rule, we define additional electrode positions. Electrodes with nonstandard positions are clustered around the closest 10-10 electrode, deemed their cardinal point. RESULTS The 256-electrode Geodesic Sensor Net mapped to 96 of the 120 extended 10-10 cardinal electrodes. CONCLUSIONS Electrode position nomenclature that builds upon the international standard 10-10 system allows electroencephalographers to identify spatial areas of interest in HD-EEG relative to positions in routine use. A standard viewing montage for HD-EEG and its application with electrical source imaging boost efficiency when reviewing data and improve accuracy in recognizing epileptiform discharges. Additionally, our proposed system is not limited to a specific HD-EEG system, electrode count, or electrode layout.

After more than 3 years of operational experiences with the Transportable Adaptive Optical Ground Station (T-AOGS) it is not any more the question whether optical communication through atmosphere is possible for Geo to ground applications. It is important to understand the performance of optical communication under different atmospheric-conditions and which the key parameters are to improve simplicity, robustness and availability of optical bi-directional satellite to ground links (SGL). We report within this paper on the characterization of the atmospheric channel for ground to GEO optical communication without adaptive optics correction in the uplink. Besides the telemetry data of the space segment and the T-AOGS, also a special measurement campaign was carried out using the 1m telescope of the ESA-OGS in parallel. An outlook for further analysis and activities is given.

Supplemental Digital Content is available in the text., Objectives: Acute stroke has a high morbidity and mortality in elderly population. Baseline confounding illnesses, initial clinical examination, and basic laboratory tests may impact prognostics. In this study, we aimed to establish a model for predicting in-hospital mortality based on clinical data available within 12 hours of hospital admission in elderly (≥ 65 age) patients who experienced stroke. Design: Retrospective observational cohort study. Setting: Academic comprehensive stroke center. Patients: Elderly acute stroke patients—2005–2009 (n = 462), 2010–2012 (n = 122), and 2016–2017 (n = 123). Interventions: None. Measurements and Main Results: After institutional review board approval, we retrospectively queried elderly stroke patients’ data from 2005 to 2009 (training dataset) to build a model to predict mortality. We designed a multivariable logistic regression model as a function of baseline severity of illness and laboratory tests, developed a nomogram, and applied it to patients from 2010 to 2012. Due to updated guidelines in 2013, we revalidated our model (2016–2017). The final model included stroke type (intracerebral hemorrhage vs ischemic stroke: odds ratio [95% CI] of 0.92 [0.50–1.68] and subarachnoid hemorrhage vs ischemic stroke: 1.0 [0.40–2.49]), year (1.01 [0.66–1.53]), age (1.78 [1.20–2.65] per 10 yr), smoking (8.0 [2.4–26.7]), mean arterial pressure less than 60 mm Hg (3.08 [1.67–5.67]), Glasgow Coma Scale (0.73 [0.66–0.80] per 1 point increment), WBC less than 11 K (0.31 [0.16–0.60]), creatinine (1.76 [1.17–2.64] for 2 vs 1), congestive heart failure (2.49 [1.06–5.82]), and warfarin (2.29 [1.17–4.47]). In summary, age, smoking, congestive heart failure, warfarin use, Glasgow Coma Scale, mean arterial pressure less than 60 mm Hg, admission WBC, and creatinine levels were independently associated with mortality in our training cohort. The model had internal area under the curve of 0.83 (0.79–0.89) after adjustment for over-fitting, indicating excellent discrimination. When applied to the test data from 2010 to 2012, the nomogram accurately predicted mortality with area under the curve of 0.79 (0.71–0.87) and scaled Brier’s score of 0.17. Revalidation of the same model in the recent dataset from 2016 to 2017 confirmed accurate prediction with area under the curve of 0.83 (0.75–0.91) and scaled Brier’s score of 0.27. Conclusions: Baseline medical problems, clinical severity, and basic laboratory tests available within the first 12 hours of admission provided strong independent predictors of in-hospital mortality in elderly acute stroke patients. Our nomogram may guide interventions to improve acute care of stroke.

Hintergrund: Ziel dieser Arbeit war es, die haufig temporaren Veranderungen der ischamischen Netzhaut mittels hochauflosender optischer Koharenztomografie (SD-OCT) morphologisch einzuordnen und zu charakterisieren sowie das Auftreten einer zusatzlichen hyperreflektiven Bande in den auseren Netzhautschichten zu beschreiben. Diese Beobachtung wurde wahrend der Auswertung von OCT-Aufnahmen bei Patienten mit einem akuten Sehverlust aufgrund einer retinalen Ischamie gemacht. Patienten und Methoden: Bei 26 Patienten (36–96 Jahre) mit einer akuten einseitigen Sehverschlechterung aufgrund von Zentralarterienverschluss, Astarterienverschluss, anteriorer ischamischer Optikusneuropathie oder Prastase wurde die Netzhaut mithilfe von SD-OCT und Fundusautofluoreszenz (FAF) untersucht. Hauptaugenmerk wurde auf den Ubergang der auseren nuklearen Schicht zur auseren plexiformen Schicht gelegt. Zusatzlich wurden Messwerte der Netzhautdicke in der Fovea, parafoveal und innerhalb der einzelnen Netzhautschichten erhoben, die mit den Messwerten an den korrespondierenden Stellen der dazugehorigen nicht betroffenen Augen verglichen wurden. SD-OCT-Aufnahmen wurden mit einem kombinierten SD-OCT und konfokalen Scanning-Laser-Ophthalmoskop (cSLO) angefertigt. Als Schnittfuhrung wurden sowohl der lineare horizontale Scan als auch der Sternscan mit einer Lange von 6 mm verwendet (ART-Modus an; durchschnittlich 20 Bilder). Ergebnisse: Im SD-OCT zeigt sich eine zusatzliche hochreflektive Bande innerhalb der auseren plexiformen Schicht. Die morphologischen Eigenschaften dieser hyperdensen Bande beinhalten eine abnehmende Intensitat mit zunehmender Entfernung von der Fovea, ein teilweise segmentales Erscheinungsbild und ein zeitlich limitiertes Auftreten. In der FAF zeigen sich Areale mit erhohter und erniedrigter Intensitat innerhalb der Gefasarkaden am hinteren Augenpol. Die Regionen mit reduzierter Intensitat in der FAF entsprachen perivenosen Regionen und gleichen dem Bild von „frosted branches“, die in der Fluoresceinangiografie bei Patienten mit okularer Ischamie beobachtet werden konnen. Schlussfolgerung: Die im SD-OCT neu auftretende hyperreflektive Bande konnte einen Marker fur eine retinale Ischamie bei denjenigen Patienten darstellen, bei denen kein kompletter Gefasverschluss nachweisbar ist. Die Lokalisation der Bande innerhalb der auseren plexiformen Schicht befindet sich am Ubergang der retinalen zur choroidalen Sauerstoffversorgung der Netzhaut. Diese Stelle markiert den Bereich mit der geringsten Diffusion von Sauerstoff. Histopathologisch konnte die beobachtete Struktur aktivierte Mikrogliazellen reprasentieren, die aufgrund der vermehrten Freisetzung von Entzundungsmediatoren bei retinaler Hypoxie zur Reparatur der Ischamie aktiviert werden.

The increasing demand on high speed communication networks has stimulated the development of optical free space data transmission during the last years. TESAT has developed a laser communication terminal (LCT) that fulfills the need of a power efficient system whose capability has been successfully demonstrated at bidirectional space-to-space links and bidirectional space-to-ground links (SGLs) at a data rate of 5.625 GBit/s with a homodyne detection scheme and a BPSK modulation format. In comparison to a direct detection system, the homodyne detection scheme works as a bandpass filter. The transmission is immune to false light and even data transmission with the sun in the receiver field of view (FOV) is possible. Compared to common RF transmission which is implemented on spacecrafts for data transmission, optical transmission provides not only higher transmission rates (factor 10) but also shows excellent security features since the laser beams directivity making it immune to interception.

The performance of sensors for Earth Observation Missions is constantly improving. This drives the need for a reliable, high-speed data transfer capability from a Low Earth Orbit (LEO) spacecraft (S/C) to ground. In addition, for the transfer of time-critical data to ground, a low latency between data generation in orbit and data reception at the respective mission control center is of high importance. Laser communication between Satellites for high data transmission in combination with a GEO data relay system for reducing the latency time addresses these requirements.

The European Data Relay System (EDRS) will provide optical and microwave data relay services between Low Earth Orbit (LEO) satellites at altitudes up to 2000 km and the ground through geostationary (GEO) satellite nodes. Currently, two such nodes have been procured as part of a Public Private Partnership (PPP) between Astrium (now Airbus Defence and Space) and ESA. The first node (EDRS-A) is a hosted payload embarked upon the Eutelsat 9B satellite and scheduled for launch in early 2015.

Quantum optics [1] can be harnessed to implement cryptographic protocols that are verifiably immune against any conceivable attack [2]. Even quantum computers, that will break most current public keys [3, 4], cannot harm quantum encryption. Based on these intriguing quantum features, metropolitan quantum networks have been implemented around the world [5-15]. However, the long-haul link between metropolitan networks is currently missing [16]. Existing fiber infrastructure is not suitable for this purpose since classical telecom repeaters cannot relay quantum states [2]. Therefore, optical satellite-to-ground communication [17-22] lends itself to bridge intercontinental distances for quantum communication [23-40].

Since the successful demonstration of the Semiconductor-laser Inter-satellite Link EXperiment (SILEX) in 2001 between ARTEMIS and SPOT-4 satellites, the European Space Agency (ESA) and several European National Space Agencies have consolidated the effort in developing the so-called “second generation” of optical communications terminals with reduced mass, size and power consumption, and increased data transmission rate, [1].

Quantum key distribution (QKD) has raised increased attention over the past years as one of the most attractive quantum technologies for practical implementation. QKD has already been implemented in intra-city networks all around the world. But up to now, bridging global distances with quantum communication remains an outstanding challenge. A promising candidate to provide this link is via optical satellite communication. As space-to-ground communication is already well developed for classical applications, one can make use of the already existing technology for QKD, i.e. modern Laser Communication Terminals (LCTs) may be adapted for quantum communication. An important first step to achieve this goal is a precise characterization of the system and the channel with regard to their quantum noise behaviour.

Introduction High density EEG (hdEEG) systems and Electrical Source Imaging (ESI) techniques have revolutionized our ability to assess the potential sources of epileptiform activity and other EEG features. HdEEG interpretation is limited by lack of standardized electrode position nomenclature and montages. Inefficient visual review of hdEEG remains a major barrier to incorporating these techniques into clinical care. The aim of this project is to propose an electrode map and nomenclature with digitized electrode locations for easy integration with neuroimaging studies and ESI. Methods The 256 channel EEG net (Geodesic Sensor Net, Electrical Geodesics, Inc.) includes electrode locations approximating the International 10–20 and 10–10 systems, but intervening electrodes do not have a standardized location, and many electrodes over the cheeks and face do not have positions defined by the 10–10 or 10–5 systems. We co-registered average 256 channel EEG net electrode positions to the 10–10 positions based on the Montreal Neurologic Institute using Curry 7.0 software. then clustered the 256 electrode locations to their closest 10–10 electrodes tested several channel layouts (montages) allowing rapid transition from global views (all head regions) to focal views (subregions corresponding to 10–10 electrode coordinates). Results 256 electrode locations were successfully clustered around their closest 10–10 electrode, deemed its cardinal point. All 256 electrodes within a cluster received the same initial letters according to the 10–10 electrode at its center. Within a cluster, the first subscript identified its position either anterior (a) or posterior (p) to the cardinal 10–10 electrode. The second subscript identified its position either superior (s) or inferior (i) to the cardinal 10–10 electrode. The last subscript, numerical, identified the proximity of the nonstandard electrode relative to the cardinal 10–10 electrode, compared to the other nonstandard electrodes in that cluster. Therefore, the closest nonstandard electrode would have the subscript as 1, and each subscript would increase in numeric value as distance from the cardinal 10–10 electrode increases. Conclusion Electrode position nomenclature which builds upon the international standard 10–10 system allows electroencephalographers to identify spatial areas of interest in hdEEG relative to positions in routine use. A standard viewing montage for hdEEG and its application with ESI both boosts efficiency when reviewing data, and also improves accuracy in recognizing epileptiform discharges. Furthermore, combining the montage with electrode geopositions will provide greater continuity and ease of use across analysis techniques that would potentially increase adoption of source analysis in clinical care. Our proposed system could also be expanded to higher numbers of electrodes or additional positions on the face or head and is not limited to a specific hdEEG system or electrode count.

Optical ground stations can be an alternative to radio frequency based transmit (forward) and receive (return) systems for data relay services and other applications including direct to earth optical communications from low earth orbit spacecrafts, deep space receivers, space based quantum key distribution systems and Tbps capacity feeder links to geostationary spacecrafts. The Tesat Transportable Adaptive Optical Ground Station is operational since September 2015 at the European Space Agency site in Tenerife, Spain.. This paper reports about the results of the 2016 experimental campaigns including the characterization of the optical channel from Tenerife for an optimized coding scheme, the performance of the T-AOGS under different atmospheric conditions and the first successful measurements of the suitability of the Alphasat LCT optical downlink performance for future continuous variable quantum key distribution systems.

Laser Communication Links in Orbit have become routine for Alphasat TDP1 GEO data relay and Sentinel-1A LEO satellite. Since November 2014, an extensive campaign has demonstrated stable and bit-error free links over distances of up to 45.000km with 1.1W optical transmit power and data rates of up to 1.8Gbps. Link acquisition is achieved reliably within less than 55s. Links with low grazing altitude investigate the impact of atmosphere to link performance. The optical links between Sentinel-1A and Alphasat are in collaboration of ESA, DLR, and TESAT Spacecom. Alphasat TDP1 is the precursor for European Data Relay Satellite System EDRS [1].

SUMOylation of transcription factors and chromatin proteins is in many cases a negative mark that recruits factors that repress gene expression. In this study, we determined the occupancy of Small Ubiquitin-like MOdifier (SUMO)-1 on chromatin in HeLa cells by use of chromatin affinity purification coupled with next-generation sequencing. We found SUMO-1 localization on chromatin was dynamic throughout the cell cycle. Surprisingly, we observed that from G1 through late S phase, but not during mitosis, SUMO-1 marks the chromatin just upstream of the transcription start site on many of the most active housekeeping genes, including genes encoding translation factors and ribosomal subunit proteins. Moreover, we found that SUMO-1 distribution on promoters was correlated with H3K4me3, another general chromatin activation mark. Depletion of SUMO-1 resulted in downregulation of the genes that were marked by SUMO-1 at their promoters during interphase, supporting the concept that the marking of promoters by SUMO-1 is associated with transcriptional activation of genes involved in ribosome biosynthesis and in the protein translation process.

Future earth observation satellites call for GEO relay links to make their data immediately available to the user. While RF communication limits the GEO relay’s data rate to roughly 1 Gbps (Gigabit per second) laser communication will extend its capacity into the 10 Gbps range as is required for the future systems. Laser communication will be applied for EDRS, the European data GEO relay system. At first, it is foreseen to provide the RF LEO-to-GEO link with an additional laser communication channel, still limiting, of course, the GEO relay’s performance to the RF bottleneck. However besides the operational service, the EDRS laser terminals shall also demonstrate the performance of high data rate links for both, the inter-satellite link and the GEO-to-ground link.

The rat is a popular animal model for vision research, yet there is little quantitative information about the physiological properties of the cells that provide its brain with visual input, the retinal ganglion cells. It is not clear whether rats even possess the full complement of ganglion cell types found in other mammals. Since such information is important for evaluating rodent models of visual disease and elucidating the function of homologous and heterologous cells in different animals, we recorded from rat ganglion cells in vivo and systematically measured their spatial receptive field (RF) properties using spot, annulus, and grating patterns. Most of the recorded cells bore likeness to cat X and Y cells, exhibiting brisk responses, center-surround RFs, and linear or nonlinear spatial summation. The others resembled various types of mammalian W cell, including local-edge-detector cells, suppressed-by-contrast cells, and an unusual type with an ON–OFF surround. They generally exhibited sluggish responses, larger RFs, and lower responsiveness. The peak responsivity of brisk-nonlinear (Y-type) cells was around twice that of brisk-linear (X-type) cells and several fold that of sluggish cells. The RF size of brisk-linear and brisk-nonlinear cells was indistinguishable, with average center and surround diameters of 5.6 ± 1.3 and 26.4 ± 11.3 deg, respectively. In contrast, the center diameter of recorded sluggish cells averaged 12.8 ± 7.9 deg. The homogeneous RF size of rat brisk cells is unlike that of cat X and Y cells, and its implication regarding the putative roles of these two ganglion cell types in visual signaling is discussed.

Purpose Our main objective was to assess incidence, risk factors, and outcomes of ventilator-associated pneumonia (VAP) in stroke patients. Materials and Methods After obtaining approval from the Human Studies Committee, we reviewed the electronic records from our intensive care unit database of 111 stroke patients on mechanical ventilation for more than 48 hours. Thirty-six risk factors related to disease and general health status, and 8 related to care—all assigned a priori—were collected and analyzed. Selected factors with univariate statistical significance (P Results Thirty-one patients developed pneumonia (28%). Methicillin-resistant Staphylococcus aureus (n = 12) and methicillin-sensitive S aureus (n = 7) were the most common pathogenic bacteria. Chronic lung disease, neurological status at admission as assessed by the National Institutes of Health Stroke Scale, and hemorrhagic transformation were the independent risk factors contributing to VAP. Worsening oxygenation index (arterial partial pressure of oxygen/fraction of inspired oxygen) and proton pump inhibitor use for ulcer prophylaxis were other potentially important factors. Conclusions Pneumonia appears as a frequent problem in mechanically ventilated stroke patients. Chronic lung disease history, severity of stroke level at admission, and hemorrhagic transformation of stroke set the stage for developing VAP. The duration of both mechanical ventilation and intensive care unit stay gets significantly prolonged by VAP, but it does not affect mortality.

Introduction Despite major advances in using high density EEG (hdEEG) and electrical source imaging (ESI) for analysis of interictal activity, research demonstrating its utility in examining ictal activity is still lacking. This may be a result of technical challenges associated with capturing epileptic seizures on scalp hdEEG recordings (physical constraints, such as high number of sensors, lack of standardization in review, comfort, etc.). Furthermore, the value of using interictal discharges as a valid estimate of seizure onset zone (SOZ) still remains disputable. The aim of this study is to use electrical source imaging (ESI) to evaluate the co-localization of ictal and interictal activity through the use of high density scalp EEG. Methods A retrospective analysis was performed on 5 patients with intractable focal temporal and extratemporal lobe epilepsy. EEG scalp recordings were obtained using high density 256 Geodesic Sensory Net (Geodesic Sensor Net, Electrical Geodesic Inc.). ESI was performed using two different commercially available ESI systems, Curry 7.0 (Compumedics) and MIPEGI (Electrical Geodesic Inc.). Sensor locations were determined using the Geodesic Photogrammetry System (GPS) and Geosource 3 (Electrical Geodesic Inc), Realistic geometric individualized head models were constructed from patient specific MRIs using the boundary element model and the finite difference model. Source reconstruction was based on distributed source models and dipole models. The concordance of irritative and ictal onset zones was estimated by the distance between maximal ictal and interictal source activity. Results ESI identified the seizure onset and irritative zones in all 5 patients. There was good concordance between the estimated seizure onset zone and irritative zone on the sub-lobar level. Similar results were obtained through the use of the boundary element and finite difference models. Conclusion The results provide insight into whether interictal discharges provide accurate estimate of SOZ. Furthermore, these results assess similarity of source reconstruction obtained through two different types of individual head models that are commercially available.

Action potentials were recorded from rat retinal ganglion cell fibers in the presence of a uniform field, and the maintained discharge pattern was characterized. Spike trains recorded under ketamine–xylazine anesthesia were generally stationary, while those recorded under urethane anesthesia often showed slow, undriven, quasiperiodic fluctuations in firing rate. In light of these nonstationarities, interspike interval distributions and power spectral densities are reported for data collected primarily under ketamine–xylazine. The majority of cells had multimodal interval distributions, with the first peak in the range of 25.0–38.5 ms and the subsequent peaks occurring at integer multiples of the first peak. Cells with unimodal distributions were fit well by a gamma distribution function. Interval and spike count statistics showed that ON cells tended to fire faster than OFF cells and that cells with higher rates fired in a more regular manner, with the coefficient of variation covering a wide range of values across all cells (0.43–0.97). Both ON and OFF cells show serial correlations between adjacent interspike intervals, while ON cells also showed second-order correlations. Cells with multimodal interval distribution showed a strong peak at high frequencies in the power spectra in the range of 28.9–41.4 Hz. Oscillations were present under both anesthetic conditions and persisted in the dark at a slightly lower frequency, implying that the oscillations are generated independent of any light stimulus but can be modulated by light level. The oscillation frequency varied slightly between cells of the same type and in the same eye, suggesting that multiple oscillatory generating mechanisms exist within the retina. Cells with high-frequency oscillations were described well by an integrate-and-fire model with the input consisting of Gaussian noise plus a sinusoid where the phase was jittered randomly to account for the bandwidth present in the oscillations.

Cellular DNA damage elicits the phosphorylation and ubiquitination of RNA polymerase II (RNAPII), leading to the global repression of transcription. In this report we show that there are at least two different pathways to transcriptional repression, depending on the type of DNA damage. After H2O2 treatment, transcription was rapidly inhibited and rapidly restored. On the other hand, UV irradiation caused a much slower transcriptional inhibition, with a corresponding depletion of unphosphorylated RNAPII. We found that after UV treatment, but not treatment with H2O2, the inhibition of transcription was dependent on both the proteasome and new protein synthesis. In addition, RNAPII activity and ubiquitination were regulated through the phosphorylation of RNAPII by the P-TEFb kinase. These results highlight that multiple cellular pathways exist to globally repress transcriptional processes that might interfere with the repair of DNA damage.

Mass radiography in juveniles between 10 and 19 years of age in Westphalia pointed to a probable incidence of thoracal scoliosis of more than 10 degrees in about 4 per cent of the girls and 1.0--1.5 per cent among boys. In both girls and boys the convexity of the scoliosis is chiefly in the right direction, especially if the apex of the curvature is positioned in cranial direction or if the findings are very pronounced. In a few exceptional cases only the apex of curvature is above Th7. Hence, most of the patients can be adequately treated by means of one of the more recent methods of orthesis.

The European Data Relay System (EDRS) relies on optical communication links between Low Earth Orbit (LEO) and geostationary (GEO) spacecrafts. Data transmission at 1,8 Gbps between the S/Cs will be applied for link distances up to 45000 km. EDRS is foreseen to go into operation in 2015. As a precursor to the EDRS GEO Laser Communication Terminals (LCT), a LCT is embarked on the Alphasat GEO S/C, which was launched in July 2013. Sentinel 1A is a LEO earth observation satellite as part of ESAs Copernicus program. Sentinel 1A also has a LCT on board. In November 2014, the first optical communication link between a LEO and a GEO Laser Communication Terminal at gigabit data rates has been performed successfully [1]. Data generated by the Sentinel 1A instrument were optically transferred to Alphasat. From Alphasat, the data were transmitted via Kaband to a ground station. In the ground station, the original data were recovered successfully. So the whole chain from LEO to ground was verified. Since then, many optical communication links between the Alphasat LCT and the Sentinel 1A LCT were performed. During these tests, the acquisition and tracking performance was investigated. The first communication links showed a very robust link acquisition capability and tracking errors in the sub-μrad range. The communication link budget was verified and compared to the predictions, showing excellent overall system behavior with sufficient margin to support future GEO GEO link applications.

The aim of this study was to investigate alterations in the neurosensory retinal morphology secondary to acute retinal ischaemic conditions. The observations were documented by spectral domain optical coherence tomography (SD-OCT, Heidelberg Engineering) and fundus autofluorescence (FAF) imaging. In addition, the occurrence of an additional hyperrefelctive band in the outer corneal layers is described. This observation was made during the evaluation of OCT images of patients with an acute loss of vision due to retinal ischaemia.SD-OCT images and FAF were used to observe the retinal structure of 26 subjects (36 to 96 years) with acute monocular visual impairment due to central retinal artery occlusion (CRAO), branch retinal artery occlusion (BRAO), anterior ischaemic optic neuropathy (AION) or impending central retinal vein occlusion were included. The main focus of attention was set on the transition of the outer nuclear layer (ONL) to outer plexiform layer (OPL). Furthermore measurements of the retinal thickness at the fovea, parafoveal and within the retinal layers were acquired and compared to corresponding points of the non-affected eyes. SD-OCT images were acquired with a combined SD-OCT and scanning laser ophthalmoscope (cSLO) imaging system using a linear cross hair scan and a 6 line radial scan of 6 mm length (ART mode on; average of 20 frames).SD-OCT revealed an additional highly reflective band located within the OPL. Morphological characteristics of this hyperdense band were a decreasing intensity with distance from the fovea, partially segmental occurrence and manifestation limited in time. FAF showed areas of increased and decreased signal intensity within the vessel arcade at the posterior pole. The regions of decreased FAF corresponded to perivenous regions and resemble the "frosted branches" sign seen in fluorescein angiography in patients with ocular ischaemia.The additional hyperreflective band observed in SD-OCT could represent a marker for retinal ischaemia in subjects without the presence of a complete vascular occlusion. The mid retinal localisation of the band within the OPL is situated at the locus of transition from retinal to choroidal oxygen supply where oxygen diffusion is weakest. Histopathologically the observed structure could represent activated microglial tissue induced by the hypoxia driven upregulation of inflammatory molecules aimed at ischaemia repair.

The European Data Relay System (EDRS) relies on optical communication links between Low Earth Orbit (LEO) and geostationary (GEO) spacecrafts. Data transmission at 1.8 Gbps between the S/Cs will be applied. EDRS is foreseen to go into operation in 2015. As a precursor to the EDRS GEO Laser Communication Terminals (LCT), an LCT is embarked on the Alphasat GEO S/C. Sentinel 1A is a LEO earth observation satellite as part of ESAs Copernicus program and carries an LCT on board. Both the Alphasat and the Sentinel 1A LCT have completed their individual in orbit commissioning and a joint link commissioning phase, with first LEO to GEO optical communication links in 2014. In this presentation, the design principle of the LCT applied for EDRS will be investigated. The most recent results of the in-orbit link commissioning phase of the LCTs on board of Alphasat and Sentinel 1A will be presented.

Regeneration in the peripheral nervous system is impaired after prolonged periods of denervation. Currently, no interventions exist to alter the outcome after prolonged denervation. To examine the role of transplanted neural stem cells (NSC), we prepared chronically denervated distal tibial nerve segments. After 6 months of chronic denervation, we transplanted vehicle, C17.2 mouse NSCs, or C17.2 mouse NSCs engineered to overexpress GDNF to the distal tibial nerve and performed a peroneal nerve cross-suture. In animals transplanted with the NSCs, there was better regeneration of the peroneal axons into the tibial nerve as measured by counting the number of axons and by the emergence of compound motor action potentials in the tibial innervated foot muscles. Improved regeneration correlated with a reduction of chondroitin sulphate proteoglycan (CSPG) immunoreactivity in the extracellular matrix (ECM). In vitro, supernatant from C17.2 NSCs contained large quantities of secreted matrix metalloprotease-2 (MMP-2), degraded the CSPGs on chronically denervated tibial nerve sections, and reversed the CSPG-induced inhibition of neuritic outgrowth of DRG neurons. This reversal was inhibited by selective MMP-2 inhibitors. This is the first successful demonstration of regeneration through a chronically denervated nerve. These findings suggest that improved regeneration in the PNS can be accomplished by combining neurotrophic factor support and removal of axon growth inhibitory components in the extracellular matrix.

Background Whole-parasite immunization remains the benchmark in malaria vaccine development. A major bottleneck in the translation of whole-parasite immunization towards routine vaccination is the mode of administration, since high degrees of protection are currently only achieved by intravenous, and not by intradermal or subcutaneous injection of viable parasites. It is known that only a small proportion of subcutaneously administered parasites reach the subsequent liver stage and low parasite liver load was shown to be associated with low protective efficacy. The objective of this analysis was to evaluate whether the liver load following subcutaneous parasite injection could be augmented by co-administration of pro-inflammatory or anti-coagulatory drugs. Methods In the C57BL/6 Plasmodium berghei ANKA model, the clinical outcome (time to patent blood stage infection and survival) and relative parasite liver load was assessed in mice infected by subcutaneous or intramuscular sporozoite (SPZ) administration in the presence or absence of histamine and heparin supplementation in comparison to intravenously administered SPZ. In addition, a vaccination experiment was carried out to assess the protective efficacy of an improved, histamine-supplemented subcutaneous immunization regimen. Results The parasite liver load following subcutaneous SPZ administration can be significantly increased by co-administration of histamine and heparin. A dose-dependent relation between parasite liver load and histamine dosage was observed. However, despite a relatively high parasite liver load, the protective efficacy of histamine-supplemented subcutaneous immunization remains inferior as compared to intravenous SPZ administration. Conclusions Histamine supplementation might facilitate the future development of a non-intravenous whole-parasite vaccine. Further investigations are needed to reveal the effect of histamine supplementation and subcutaneous SPZ administration on the acquisition of protective immunity. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0552-3) contains supplementary material, which is available to authorized users.

Nijmegen breakage syndrome (NBS) is a rare human disease displaying chromosome instability, radiosensitivity, cancer predisposition, immunodeficiency, and other defects [1, 2]. NBS is complexed with MRE11 and RAD50 in a DNA repair complex [3–5] and is localized to telomere ends in association with TRF proteins [6, 7]. We show that blood cells from NBS patients have shortened telomere DNA ends. Likewise, cultured NBS fibroblasts that exhibit a premature growth cessation were observed with correspondingly shortened telomeres. Introduction of the catalytic subunit of telomerase, TERT, was alone sufficient to increase the proliferative capacity of NBS fibroblasts. However, NBS, but not TERT, restores the capacity of NBS cells to survive γ irradiation damage. Strikingly, NBS promotes telomere elongation in conjunction with TERT in NBS fibroblasts. These results suggest that NBS is a required accessory protein for telomere extension. Since NBS patients have shortened telomeres, these defects may contribute to the chromosome instability and disease associated with NBS patients.

Nijmegen breakage syndrome (NBS) is characterized by extreme radiation sensitivity, chromosomal instability and cancer1. The phenotypes are similar to those of ataxia telangiectasia mutated (ATM) disease, where there is a deficiency in a protein kinase that is activated by DNA damage, indicating that the Nbs and Atm proteins may participate in common pathways. Here we report that Nbs is specifically phosphorylated in response to γ-radiation, ultraviolet light and exposure to hydroxyurea. Phosphorylation of Nbs mediated by γ-radiation, but not that induced by hydroxyurea or ultraviolet light, was markedly reduced in ATM cells. In vivo, Nbs was phosphorylated on many serine residues, of which S343, S397 and S615 were phosphorylated by Atm in vitro. At least two of these sites were underphosphorylated in ATM cells. Inactivation of these serines by mutation partially abrogated Atm-dependent phosphorylation. Reconstituting NBS cells with a mutant form of Nbs that cannot be phosphorylated at selected, ATM-dependent serine residues led to a specific reduction in clonogenic survival after γ-radiation. Thus, phosphorylation of Nbs by Atm is critical for certain responses of human cells to DNA damage.

We observed the bound-state β− decay of fully ionized 187Re-nuclei circulating in the experimental storage ring ESR at GSI. 187Re ions were accelerated in the GSI accelerator complex to a final energy of 347 MeV/u, fully stripped and injected into the ESR. During storage times of up to four hours, several hundred 187Os75+ ions were produced via bound-state β− decay of 187Re75+ ions and circulating on almost the same orbit. To separate the 187Os ions from their mother nuclei, an internal Ar gas jet target was used to strip off the last electron and produce 187Os76+. As a result of the higher charge state the 187Os ions now were stronger deflected by the following dipole magnet, and detected in a position sensitive microstrip-gas-counter. The determined half-life is T 1 2 = 31.2 −2.5 +3.0 yr . With the now measured 187Re half-life the 187 Re 187 Os cosmochronometer can be recalibrated. By taking into account the β− decay enhancement in stellar interiors, this ‘clock’ will lead to a more accurate estimation of the Galactic age.

Whereas neutral 187Re has a half-life of ≈ 4 · 1010 yr, one expects for fully stripped 187Re75+ a half-life of < 100 yr, as it can decay into bound electronic states of the first excited state of the daughter isotope, 187Os75+. The latter decay occurs in hot stellar plasmas and must therefore be known if one wishes to infer from the 187Re187Os ratio found in meteorites the age of the material in our solar system. This decay was measured for the first time in an experiment performed at the heavy ion storage ring ESR of GSI. 187Re75+ ions were produced by stripping in a thick copper target after acceleration to 350 MeV per nucleon in the heavy ion synchrotron SIS. Up to 1.7 · 108 ions were stored in the ESR ring at a time. After different storage times (up to 5h), the hydrogen-like decay products were stripped in an internal argon gas jet target. The number of stripped 187Os76+ ions was determined in two independent experiments. In the first one the osmium ions were counted in a microstrip gas counter. In the second experiment, the 187Os76+ ions were still circulating in the storage ring and their number was determined non-destructively by Schottky spectroscopy. In both cases, a separation of the beta decay products from nuclear fragments produced either in the rest gas or the internal target was possible. One can safely exclude that a major fraction of the 187Os ions were produced by n-p exchange reactions. Rates for stripping in the gas jet and the relevant particle loss rates were determined independently.

We have identified the doubly-magic N = Z nucleus 100Sn by using the method of high-energy projectile fragmentation of a 124Xe beam in connection with the fragment separator FRS at GSI. Despite a very low production cross section of only 11 ± 4 pb, we report on first results from the investigation of correlated β-decays after the implantation of a total seven nuclei into a segmented stack of silicon detectors. We will discuss future perspectives of a more precise determination of the GT-hindrance factor for the unique 100Sn β-decay using the same method.

During the early phase of the discharge (ignition), fast ionization waves are observed propagating with a velocity of 10/sup 6/ m/s from cathode to anode. During this transient phase, a first peak of an energetic electron beam develops. Simultaneously, a moderate radial expansion of the axially concentrated background plasma (produced from beam electrons) is observed, but the plasma parameter remains still smaller than the borehole diameter (equal to 3 mm). The transition into the high current phase is characterized by further continuous radial expansion of background plasma, which is interrupted by a sudden and rapid radial expansion of plasma into the last two or three gaps in front of the anode. One reasonable explanation is based upon a kind of plasma blow-up by the field of the space charge accumulated there. Part of the beam electrons, extracted from the hollow cathode and adjacent gaps, are apparently deflected or even reflected in this high local electric field. Parallel with increasing total current, the internal resistance of the system drops dramatically, synonymous with the energy of the beam electrons, too. Characteristic for the development of the hollow-cathode plasma is a stepwise expansion. The plasma itself develops a hollow structure, and the diameter of it is still larger than the borehole diameter. During the high-current phase, the diameter of this characteristic hollow structure increases rapidly to the wall, indicating the end of the first current half-wave.

Tesat is performing inter-satellite links (ISLs) for over 5 years now. Besides the successful demonstration of the suitability of coherent laser communication for high speed data transmission in space, Tesat has also conducted two major satellite to ground link (SGL) campaigns during the last 3 years. A transportable ground station has been developed to measure the impact of atmospheric turbulence to the coherent system. The SGLs have been performed between the Tesat optical ground station and the two LEO satellites TerraSAR-X and NFIRE, both equipped with a Tesat LCT. The capability of the LCTs of measuring the signal intensity on a direct detection sensor and on a coherent sensor simultaneously makes the system unique for investigating the atmospheric distortion impacts. In this paper the main results of the SGL campaigns are presented, including BER performance for the uplink and downlink. Measured scintillation profiles versus elevation angles at different weather conditions are illustrated. Finally preliminary results of an adaptive optics system are presented that has been developed to be used in the transportable adaptive optical ground station (T-AOGS) acting as the counter terminal for the LCT mounted on Alphasat, a geostationary satellite of the European Space Agency (ESA), in autumn 2013.

We observed the bound-state ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay of fully ionized ${}^{187}$Re nuclei circulating in a storage ring. With two independent methods the time dependent growth of hydrogenlike ${}^{187}$Os ions has been measured and a half-life of $32.9\ifmmode\pm\else\textpm\fi{}2.0\mathrm{yr}$ for bare ${}^{187}$Re nuclei could be determined, to be compared with 42 Gyr for neutral ${}^{187}$Re atoms. With the resulting $\mathrm{log}\mathrm{ft}$ value of $7.87\ifmmode\pm\else\textpm\fi{}0.03$ the half-life of ${}^{187}$Re ions in any ionization state can be calculated. Thus one can correct the ${}^{187}$Re${\ensuremath{-}}^{187}$Os galactic chronometer calibration, by taking account of the ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay enhancement in stellar interiors, which will lead to a more accurate estimate of the galactic age.

Effective triggering of pseudospark switches with long lifetime and low jitter remains an important problem. This paper presents results of investigations of trigger methods for pseudospark switches. based upon pulsed glow discharges in planar and hollow electrode geometry for charge injection. The influence of different wiring and geometries of the electrodes for preionization is investigated. The effect of additional blocking potentials in the hollow cathode to improve different trigger systems was measured. Calculations of the static potential in the hollow cathode with or without blocking potential are compared with parameters of the discharge. >

We report results of the development of fast closing switches, so-called pseudospark switches, at Erlangen University. Two different parameter regimes are under investigation: medium power switches (32 kV anode voltage, 30 kA anode current and 0.02 C charge transfer per shot) for pulsed gas discharge lasers and high power switches (30 kV anode voltage, 400 kA anode current and 3.4 C charge transfer per shot) for high current applications. The lifetime of these switches is determined by erosion of the cathode. The total charge transfer of devices with one discharge channel is about 220 kC for the medium and 27 kC for the high power switch. At currents exceeding 45 kA a sudden increase in erosion rate was observed. Multichannel devices are suited to increase lifetime as the current per channel can be reduced. Successful experiments with radial and coaxial arrangements of the discharge channels were performed. In these systems the discharge channels move due to magnetic forces. A skilful use of this phenomena will result in a considerably increase of switch lifetime. Multigap devices enable an increase of anode voltage. A three gap switch has run reliably at an anode voltage of 70 kV. >

We report the first observation of the doubly-magic nucleus 100 Sn. The isotope was produced by nuclear fragmentation of 124 Xe projectiles at 1095 A·MeV using the heavy-ion synchrotron SIS at GSI Darmstadt. The projectile fragments were separated in flight with the projectile-fragment separator FRS and identified by measuring event by event the magnetic rigidity, the time of flight and the energy deposition. After identification the ions were implanted into a silicon detector stack and the decay was studied. We report preliminary results of the halflife determination.

We report the first observation of the doubly-magic nucleus 100Sn. This isotope was produced by nuclear fragmentation of 124Xe projectiles at 1095 A MeV using the heavy-ion synchrotron SIS at GSI, Darmstadt. The projectile fragments were separated in flight with the projectile fragment separator FRS and identified by measuring event by event magnetic rigidity, the time of flight and the energy deposition. The analysis of the decay events following the implantation of the fragments into a stack of Si detectors revealed for the first time the halflives of the isotopes 100Sn, 104Sb, 105Sb.

Optical inter-satellite communication has been verified in-orbit. Between two LEO satellites bit error rates better than 10−11 at a data rate of 5.625 Gbps are achieved. Optical LEO-to-ground and ground-to-LEO links have been demonstrated. For the first time ESA will apply optical communication for operational services. The LEO-to-GEO link of a GEO relay, EDRS, the European data relay system, shall be established by optical communication at a data rate of 1.8 Gbps with a bit error rate of 10−8. For the time being the GEO-to-ground link still is based on radio frequency communication limiting the overall GEO relay data rate to the value of about 2 Gbps. Significantly higher data rates will be achieved by optical space-to-ground links with ground stations equipped with adaptive optics as has been demonstrated in a free-field measurement campaign. Optical LEO-to-ground and GEO-to-ground links shall be verified in the near future. Optical Air-to-GEO links are under preparation.

We analyzed modification of chromatin by ubiquitination in human cells and whether this mark changes through the cell cycle. HeLa cells were synchronized at different stages and regions of the genome with ubiquitinated chromatin were identified by affinity purification coupled with next-generation sequencing. During interphase, ubiquitin marked the chromatin on the transcribed regions of ∼70% of highly active genes and deposition of this mark was sensitive to transcriptional inhibition. Promoters of nearly half of the active genes were highly ubiquitinated specifically during mitosis. The ubiquitination at the coding regions in interphase but not at promoters during mitosis was enriched for ubH2B and dependent on the presence of RNF20. Ubiquitin labeling of both promoters during mitosis and transcribed regions during interphase, correlated with active histone marks H3K4me3 and H3K36me3 but not a repressive histone modification, H3K27me3. The high level of ubiquitination at the promoter chromatin during mitosis was transient and was removed within 2 h after the cells exited mitosis and entered the next cell cycle. These results reveal that the ubiquitination of promoter chromatin during mitosis is a bookmark identifying active genes during chromosomal condensation in mitosis, and we suggest that this process facilitates transcriptional reactivation post-mitosis.

Both ranitidine and metoclopramide produce neuropsychiatric side effects. Concomitant use of these drugs preoperatively may produce adverse behavioral and emotional changes. Therefore in 123 unpremedicated patients undergoing tubal occlusion behavior cognitive function and affect were studied before and after a 2-minute intravenous injection of placebo (n = 30) ranitidine 50 mg (n = 32) metoclopramide 10 mg (n = 30) or both ranitidine 50 mg and metoclopramide 10 mg (n = 31). Cognitive function was evaluated by the responses to 11 statements devised to assess attitude toward anesthesia and surgery. Affect was assessed by the word chosen out of 11 word-pairs as best describing the feelings at the time. After ranitidine injection one patient seemed restless and five seemed drowsy. The changes were associated with subjective feelings of agitation (p < 0.05) and restlessness (p < 0.05). After metoclopramide injection 6 (20%) developed akathisia 13 (43.3%) seemed restless and 8 (26.7%) seemed drowsy. The changes were associated with subjective sensation of jumpiness (p < 0.01) and discomfort (p < 0.05). When both ranitidine and metoclopramide were injected 10 (32.3%) developed akathisia 4 (12.4%) seemed restless and 11 (35.5%) seemed drowsy. The changes were associated with subjective feelings of agitation (p < 0.05) jumpiness (p < 0.05) restlessness (p < 0.01) and upset (p < 0.05). Akathisia a side effect of metoclopramide seemed to be more prominent when ranitidine was added. (authors)

5.625 Gbps bidirectional laser communication at 1064 nm has been demonstrated on a repeatable basis between a Tesat coherent laser communication terminal with a 6.5 cm diameter ground aperture mounted inside the European Space Agency Optical Ground Station dome at Izana, Tenerife and a similar space based terminal (12.4 cm diameter aperture) on the Near Field Infrared Experiment low earth orbiting spacecraft. Both night and day bidirectional links were demonstrated with the longest being 177 seconds in duration. Correlation with atmospheric models and preliminary atmospheric r 0 and scintillation measurements have been made for the conditions tested, suggesting that such coherent systems can be deployed successfully at still lower altitudes without resorting to the use of adaptive optics for compensation.

The rat hippocampal slice preparation and its electrophysiology were used to assess the toxicity of two sulfur-containing amino acids, L-cysteate (CA) and L-cysteine (CYS). Both compounds were innocuous under normal conditions but became toxic in energy-deprived (lack of oxygen or glucose) slices. CA and CYS toxicity was apparent as both reduced the number of slices that normally recover their neuronal function (evoked CA1 population spike) after a standardized period of hypoxia or glucose deprivation (GD). The competitive N-methyl-D-aspartate (NMDA) antagonist DL-2-amino-5-phosphonovalerate blocked the toxicity of both CA and CYS in hypoxic slices, but it was effective only against CYS toxicity in glucose-deprived slices. The glycine antagonist 7-chlorokynurenate blocked CA and CYS toxicity in hypoxic slices but was unable to block their toxicity in glucose-deprived tissue. Perfusing slices with medium containing a high magnesium concentration blocked the toxicity of CA in both hypoxic and glucose-deprived slices, a treatment that was ineffective against CYS toxicity under either condition. Calcium depletion from the perfusion medium completely blocked the damaging effect of both amino acids in hypoxic slices, but it only partially blocked the toxicity of CA and did not block that of CYS in glucose-deprived slices. These results suggest that CA and CYS activate different NMDA receptor subsets and other glutamate receptor subtypes. Moreover, the results indicate a possible difference between the mechanism that lead to hypoxic neuronal damage and the one that lead to hypoglycemic neuronal damage.

Optical inter-satellite communication based on TESAT Laser Communication Terminals (LCT's) is operational by now on LEO satellites for more than two years. The LCT's demonstrate their performance in LEO-LEO inter-satellite links (ISL) and they are used also for LEO-to-ground links to investigate beam propagation through the atmosphere. Based on homodyne BPSK, a highly robust and sun light immune modulation scheme, the LCT's offer a full duplex data rate of 5.625 Gbps at a bit error rate lower than 10−9 for ISL. The LCT operations in the dynamic LEO scenario has shown that spatial and frequency acquisition can reliably be achieved within a few seconds. Due to its demonstrated performance, TESAT LCT's were selected for the European Data Relay Satellite (EDRS) Program of the European Space Agency. Their performance features makes them well suited also for commercial GEO data relay applications and government system requiring high data rates for LEO-to-GEO and UAV-to-GEO links.