Kerr nonlinearity mitigation in 5 × 28-GBd PDM 16-QAM signal transmission over a dispersion-uncompensated link with backward-pumped distributed Raman amplification

International audienceWe present experimental and numerical investigations of Kerr nonlinearity compensation in a 400-km standard single-mode fiber link with distributed Raman amplification with backward pumping. A dual-pump polarization-independent fiber-based optical parametric amplifier is used for mid-link spectral inversion of 5 × 28-GBd polarization-multiplexed 16-QAM signals. Signal quality factor (Q-factor) improvements of 1.1 dB and 0.8 dB were obtained in the cases of a single-channel and a five-channel wavelength-division multiplexing (WDM) system, respectively. The experimental results are compared to numerical simulations with good agreement. It is also shown with simulations that a maximum transmission reach of 2400 km enabled by the optical phase conjugator is possible for the WDM signal

Kingdon's Multiple Streams Approach in new political contexts: Consolidation, configuration, and new findings

There is a need to conduct more diverse cross-case analyses in the Multiple Streams Approach (MSA) literature which originated in the United States, to show how key concepts, such as a windows-of-opportunity and the role of policy entrepreneurs, manifest in different political contexts. We apply Qualitative Comparative Analysis for a cross-case analysis of a unique dataset representing 20 countries from four continents. This approach allows us to highlight distinct pathways to influencing policies. We identify four configurations for expanding civic spaces and two configurations for changing policies. We identify three findings novel to MSA: there are two distinctive policy entrepreneur roles involving local and international civil society actors; effective entrepreneurship is conditional on strengthening civic voice and creating civic space conducive to advocacy; and, therefore, effective entrepreneurs often must focus on expanding the civic space to discuss policy problems and the technical and political feasibility of policy solution

The transplant cohort of the German center for infection research (DZIF Tx-Cohort) : study design and baseline characteristics

Infectious complications are the major cause of morbidity and mortality after solid organ and stem cell transplantation. To better understand host and environmental factors associated with an increased risk of infection as well as the effect of infections on function and survival of transplanted organs, we established the DZIF Transplant Cohort, a multicentre prospective cohort study within the organizational structure of the German Center for Infection Research. At time of transplantation, heart-, kidney-, lung-, liver-, pancreas- and hematopoetic stem cell- transplanted patients are enrolled into the study. Follow-up visits are scheduled at 3, 6, 9, 12 months after transplantation, and annually thereafter; extracurricular visits are conducted in case of infectious complications. Comprehensive standard operating procedures, web-based data collection and monitoring tools as well as a state of the art biobanking concept for blood, purified PBMCs, urine, and faeces samples ensure high quality of data and biosample collection. By collecting detailed information on immunosuppressive medication, infectious complications, type of infectious agent and therapy, as well as by providing corresponding biosamples, the cohort will establish the foundation for a broad spectrum of studies in the field of infectious diseases and transplant medicine. By January 2020, baseline data and biosamples of about 1400 patients have been collected. We plan to recruit 3500 patients by 2023, and continue follow-up visits and the documentation of infectious events at least until 2025. Information about the DZIF Transplant Cohort is available at https://www.dzif.de/en/working-group/transplant-cohort

40 GHz small-signal cross-gain modulation in 1.3m quantum dot semiconductor optical amplifiers

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 93, 051110 (2008) and may be found at https://doi.org/10.1063/1.2969060.Small-signal cross-gain modulation of quantum dot based semiconductor optical amplifiers (QD SOAs), having a dot-in-a-well structure, is presented, demonstrating superiority for ultrahigh bit rate wavelength conversion. Optimization of the QD SOA high speed characteristics via bias current and optical pump power is presented and a small-signal 3 dB bandwidth exceeding 40 GHz is demonstrated. The -doped samples investigated here enable small-signal wavelength conversion within a range of 30 nm, limited mainly by the gain bandwidth.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, BauelementeEC/FP6/027638/EU/Transparent Ring Interconnection Using Multiwavelngth PHotonic switches/TRIUMPHEC/FP6/500101/EU/Self-Assembled semiconductor Nanostructures for new Devices in photonics and Electronics/SANDI

Granulocyte-Colony Stimulating Factor (G-CSF) Improves Motor Recovery in the Rat Impactor Model for Spinal Cord Injury

Granulocyte-colony stimulating factor (G-CSF) improves outcome after experimental SCI by counteracting apoptosis, and enhancing connectivity in the injured spinal cord. Previously we have employed the mouse hemisection SCI model and studied motor function after subcutaneous or transgenic delivery of the protein. To further broaden confidence in animal efficacy data we sought to determine efficacy in a different model and a different species. Here we investigated the effects of G-CSF in Wistar rats using the New York University Impactor. In this model, corroborating our previous data, rats treated subcutaneously with G-CSF over 2 weeks show significant improvement of motor function

Granulocyte-colony stimulating factor improves outcome in a mouse model of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease that results in progressive loss of motoneurons, motor weakness and death within 1–5 years after disease onset. Therapeutic options remain limited despite a substantial number of approaches that have been tested clinically. In particular, various neurotrophic factors have been investigated. Failure in these trials has been largely ascribed to problems of insufficient dosing or inability to cross the blood–brain barrier (BBB). We have recently uncovered the neurotrophic properties of the haematopoietic protein granulocyte-colony stimulating factor (G-CSF). The protein is clinically well tolerated and crosses the intact BBB. This study examined the potential role of G-CSF in motoneuron diseases. We investigated the expression of the G-CSF receptor in motoneurons and studied effects of G-CSF in a motoneuron cell line and in the SOD1(G93A) transgenic mouse model. The neurotrophic growth factor was applied both by continuous subcutaneous delivery and CNS-targeted transgenic overexpression. This study shows that given at the stage of the disease where muscle denervation is already evident, G-CSF leads to significant improvement in motor performance, delays the onset of severe motor impairment and prolongs overall survival of SOD1(G93A)tg mice. The G-CSF receptor is expressed by motoneurons and G-CSF protects cultured motoneuronal cells from apoptosis. In ALS mice, G-CSF increased survival of motoneurons and decreased muscular denervation atrophy. We conclude that G-CSF is a novel neurotrophic factor for motoneurons that is an attractive and feasible drug candidate for the treatment of ALS

How do apprentices moderate the influence of organizational innovation on the technological innovation process?

This paper contributes to the literature on non-monetary benefits of Vocational Education and Training (VET) by investigating its influence on a firm’s innovation process. While an increasing number of studies finds positive effects of VET on innovation in firms, the role that apprentices play in this mechanism has largely been unexplored. To analyze this role, we use the distinction between technological and organizational innovation, two complementary forms of innovation. When investigating the initiators of organizational innovation, to date, research has primarily focused on internal and external change agents at upper echelons. We conceptualize apprentices as hybrid (a combination of internal and external) change agents at lower echelons. We examine how apprentices in the Swiss VET system are key to integrating external knowledge (through school-based education) with internal knowledge (through on-the-job training) and moderating the influence of organizational innovation on technological innovation. Drawing on a sample of 1,240 firms from a representative Swiss Innovation Survey, we show that apprentices leverage the positive association between innovations in a firm’s business processes and organization of work with incremental innovations. With the description of a new mechanism that shows the significant role of apprentices on firms’ technological innovation activities and evidence for supportive associations between key variables, we contribute to the understanding of the influence of VET on innovation in firms

How do apprentices moderate the influence of organizational innovation on the technological innovation process?

This paper contributes to the literature on non-monetary benefits of Vocational Education and Training (VET) by investigating its influence on a firm’s innovation process. While an increasing number of studies finds positive effects of VET on innovation in firms, the role that apprentices play in this mechanism has largely been unexplored. To analyze this role, we use the distinction between technological and organizational innovation, two complementary forms of innovation. When investigating the initiators of organizational innovation, to date, research has primarily focused on internal and external change agents at upper echelons. We conceptualize apprentices as hybrid (a combination of internal and external) change agents at lower echelons. We examine how apprentices in the Swiss VET system are key to integrating external knowledge (through school-based education) with internal knowledge (through on-the-job training) and moderating the influence of organizational innovation on technological innovation. Drawing on a sample of 1240 firms from a representative Swiss Innovation Survey, we show that apprentices leverage the positive association between innovations in a firm’s business processes and organization of work with incremental innovations. With the description of a new mechanism that shows the significant role of apprentices on firms’ technological innovation activities and evidence for supportive associations between key variables, we contribute to the understanding of the influence of VET on innovation in firms

Robust Joint Multi-Antenna Spoofing Detection and Attitude Estimation using Direction Assisted Multiple Hypotheses RAIM

The paper presents an approach for detection of spoofing/meaconing signals using the direction-of-arrival (DOA) measurements available in a multi-antenna navigation receiver. The detection is based on comparison and statistically testing of the measured DOAs against the expected DOAs. The expected DOAs are computed in the receiver using the almanac and ephemeris information while performing the estimation of the user position. The attitude of the antenna array is assumed to be unknown and therefore has to be estimated as well. Consequently, the detection of spoofing/meaconing signals using this approach is treated as a joint detection/estimation problem. The solution to this problem is described in this paper. In addition, the performance of the proposed approach is analyzed through simulations in exemplary artificial scenarios and by processing real DOA measurement data collected during measurement campaigns