Deguelin Attenuates Reperfusion Injury and Improves Outcome after Orthotopic Lung Transplantation in the Rat

The main goal of adequate organ preservation is to avoid further cellular metabolism during the phase of ischemia. However, modern preservation solutions do rarely achieve this target. In donor organs hypoxia and ischemia induce a broad spectrum of pathologic molecular mechanisms favoring primary graft dysfunction (PGD) after transplantation. Increased hypoxia-induced transcriptional activity leads to increased vascular permeability which in turn is the soil of a reperfusion edema and the enhancement of a pro-inflammatory response in the graft after reperfusion. We hypothesize that inhibition of the respiration chain in mitochondria and thus inhibition of the hypoxia induced mechanisms might reduce reperfusion edema and consecutively improve survival in vivo. In this study we demonstrate that the rotenoid Deguelin reduces the expression of hypoxia induced target genes, and especially VEGF-A, dose-dependently in hypoxic human lung derived cells. Furthermore, Deguelin significantly suppresses the mRNA expression of the HIF target genes VEGF-A, the pro-inflammatory CXCR4 and ICAM-1 in ischemic lungs vs. control lungs. After lung transplantation, the VEGF-A induced reperfusion-edema is significantly lower in Deguelin-treated animals than in controls. Deguelin-treated rats exhibit a significantly increased survival-rate after transplantation. Additionally, a downregulation of the pro-inflammatory molecules ICAM-1 and CXCR4 and an increase in the recruitment of immunomodulatory monocytes (CD163+ and CD68+) to the transplanted organ involving the IL4 pathway was observed. Therefore, we conclude that ischemic periods preceding reperfusion are mainly responsible for the increased vascular permeability via upregulation of VEGF. Together with this, the resulting endothelial dysfunction also enhances inflammation and consequently lung dysfunction. Deguelin significantly decreases a VEGF-A induced reperfusion edema, induces the recruitment of immunomodulatory monocytes and thus improves organ function and survival after lung transplantation by interfering with hypoxia induced signaling

Coordinated medium access in wireless industrial D2D networks: Fast handshake procedures based on stable matching variants

We study the medium access of wireless device-to-device links in industrial factory environments characterized by high reliability and low latency communication requirements. We propose fast handshake procedures between the devices and a coordinator which allows several transmitter-receiver pairs to access the same frequency resource within a cell. Our framework relies on game-theoretic stable matching. We exploit many-to-one and many-to-many matching variants together with truncated schemes to achieve low-complex implementations. Furthermore, we consider power allocation with SINR guarantees to ensure reliable data transmission on resources under frequency reuse. Performance results for industrial indoor propagation at 5.2 GHz complement previous analytical work

Joint multicell subchannel assignment with interference control and resource fairness in multiband OFDMA cellular networks

Optimized distribution of downlink resources to users is a key challenge in future cellular communication systems with increasing base station density. Mobile broadband networks are expected to operate under frequency reuse factor one and are therefore interference-limited. We derive a novel framework for resource-fair sum rate maximization in OFDMA multicell deployments with single antenna links where power allocation among subchannels is predefined. The framework holds for multiband scenarios with non-contiguously aggregated carriers. Our proposed algorithm for joint subchannel scheduling is based on semidefinite reformulation and programming techniques. It has a significant contribution by taking into account active control of inter-cell interference on shared frequency resources. We achieve throughput bounds and near-optimal feasible sum rates under guarantee of interference temperature constraints by extensively exploiting all degrees of the three-dimensional binary assignment problem. We give simulation results that are compliant with wireless propagation assumptions under the Long Term Evolution (LTE) standard. Moreover, we show that the network performance can gain substantial improvements by our scheme when compared to the current generation of wireless networks where subchannel assignment has distributed implementations among locally operating cell sites

YAC 1.2.0: new aspects for coupling software in Earth system modelling

A lightweight software library has been developed to realise the coupling of Earth system model components. The software provides parallelised two-dimensional neighbourhood search, interpolation, and communication for the coupling between any two model components. The software offers flexible coupling of physical fields defined on regular and irregular grids on the sphere without a priori assumptions about grid structure or grid element types. All supported grids can be combined with any of the supported interpolations. We describe the new aspects of our approach and provide an overview of the implemented functionality and of some algorithms we use. Preliminary performance measurements for a set of realistic use cases are presented to demonstrate the potential performance and scalability of our approach. YAC 1.2.0 is now used for the coupling of the model components in the Icosahedral Nonhydrostatic (ICON) general circulation model

A Tactile Internet demonstration: 1ms ultra low delay for wireless communications towards 5G

Communication technologies of the Tactile Internet have to achieve a combination of extremely low latency under high reliability and security constraints. The targeted applications are in the fields of industry automation and transport systems, healthcare, education and gaming. 5G addresses tactile use cases under the term mission-critical machine type communication. We demonstrate a first implementation of a wireless broadband communication system utilizing 20MHz bandwidth which can achieve a round-trip delay below 1 ms. Delay measurements were performed between two endpoints over the air. The system is based on a flexible Software Defined Radio (SDR) toolkit with PHY and MAC signal processing algorithms implemented on a multi-core DSP platform. The demonstration shows a live end-to-end transmission of real data packets while at the same time evaluating latency probes. In addition, we show the general feasibility of real-time implementation of ultra-low delay signal processing on SDRs

System level performance of cellular networks utilizing ASA/LSA mechanisms

Flexible and efficient spectrum usage in cellular communication systems is a key to meet the service demand of forthcoming 4G and 5G networks by 2020. Recent wide-band power measurements in an urban environment show that spectrum below 6 GHz is still under-utilized. Licensed shared access (LSA) is one technique which can be deployed to make use of these valuable resources. In this paper we highlight cell-planning aspects for the implementation of licensed shared access (LSA) in LTE cellular networks. Different cellular deployments are evaluated by means of system-level simulations. Numerical results show that transmit power, antenna type and orientation, as well as antenna downtilt should be carefully evaluated during the planning of spectrum sharing deployments using LSA in cellular wireless

An advanced hardware platform to verify 5G wireless communication concepts

Verification of first 5G concepts of a new air interface with real hardware prototypes is challenging. In this paper, we highlight a flexible software-defined radio (SDR) platform which can be used to implement novel 5G communication concepts. The proposed software and hardware architecture was previously used to implement early LTE-Advanced features, e.g. flexible multiband carrier-aggregation (CA). Furthermore, the prototype was used for transmission experiments of new multi carrier waveforms. The proposed setup allows early proof-of-concepts (PoC) by extending hardware-in-the-loop (HILO) experiments to small laboratory experiments and finally real outdoor test trials of a novel 5G air interface and concepts