5GNOW: Challenging the LTE Design Paradigms of Orthogonality and Synchronicity

LTE and LTE-Advanced have been optimized to deliver high bandwidth pipes to wireless users. The transport mechanisms have been tailored to maximize single cell performance by enforcing strict synchronism and orthogonality within a single cell and within a single contiguous frequency band. Various emerging trends reveal major shortcomings of those design criteria: 1) The fraction of machine-type-communications (MTC) is growing fast. Transmissions of this kind are suffering from the bulky procedures necessary to ensure strict synchronism. 2) Collaborative schemes have been introduced to boost capacity and coverage (CoMP), and wireless networks are becoming more and more heterogeneous following the non-uniform distribution of users. Tremendous efforts must be spent to collect the gains and to manage such systems under the premise of strict synchronism and orthogonality. 3) The advent of the Digital Agenda and the introduction of carrier aggregation are forcing the transmission systems to deal with fragmented spectrum. 5GNOW is an European research project supported by the European Commission within FP7 ICT Call 8. It will question the design targets of LTE and LTE-Advanced having these shortcomings in mind and the obedience to strict synchronism and orthogonality will be challenged. It will develop new PHY and MAC layer concepts being better suited to meet the upcoming needs with respect to service variety and heterogeneous transmission setups. Wireless transmission networks following the outcomes of 5GNOW will be better suited to meet the manifoldness of services, device classes and transmission setups present in envisioned future scenarios like smart cities. The integration of systems relying heavily on MTC into the communication network will be eased. The per-user experience will be more uniform and satisfying. To ensure this 5GNOW will contribute to upcoming 5G standardization.Comment: Submitted to Workshop on Mobile and Wireless Communication Systems for 2020 and beyond (at IEEE VTC 2013, Spring

Stay by thy neighbor? Social organization determines the efficiency of biodiversity markets with spatial incentives

Market-based conservation instruments, such as payments, auctions or tradable permits, are environmental policies that create financial incentives for landowners to engage in voluntary conservation on their land. But what if ecological processes operate across property boundaries and land use decisions on one property influence ecosystem functions on neighboring sites? This paper examines how to account for such spatial externalities when designing market-based conservation instruments. We use an agent-based model to analyze different spatial metrics and their implications on land use decisions in a dynamic cost environment. The model contains a number of alternative submodels which differ in incentive design and social interactions of agents, the latter including coordinating as well as cooperating behavior of agents. We find that incentive design and social interactions have a strong influence on the spatial allocation and the costs of the conservation market.Comment: 11 pages, 6 figure

Characterization of the first potent and selective PDE9 inhibitor using a cGMP reporter cell

ABSTRACT We report here the in vitro characterization of 1-(2-chlorophenyl)-6-[(2R)-3,3,3-trifluoro-2-methylpropyl]-1,5-dihydro-4H-pyrazolo [3,4-d]pyrimidine-4-one , the first potent and selective inhibitor of phosphodiesterase 9 (PDE9), which is currently under preclinical development for the treatment of Alzheimer's disease. This compound selectively inhibits human (IC 50 ϭ 55 nM) and murine (IC 50 ϭ 100 nM) PDE9 activity in vitro and shows only moderate activity against other cyclic nucleotide-specific phosphodiesterases. We also report the generation and characterization of a stably transfected PDE9 Chinese hamster ovary cell line, additionally expressing soluble guanylate cyclase (sGC), the olfactory cyclic nucleotide-gated cation channel CNGA2 and the photoprotein aequorin. In this cell line, intracellular cGMP levels can be monitored in real-time via aequorin luminescence induced by Ca 2ϩ influx through CNGA2, acting as the intracellular cGMP sensor. This simple and sensitive assay system was used for the characterization of the cellular activity of the new PDE9 inhibitor. BAY 73-6691 alone did not significantly increase basal cGMP levels in this experimental setting. However, in combination with submaximal stimulating concentrations of the sGC activator 4-[((4-carboxybutyl){2-[(4-phenethylbenzyl)oxy]phenethyl}amino)methyl] benzoic acid (BAY 58-2667), the compound induced concentration-dependent luminescence signals and intracellular cGMP accumulation. The PDE9 inhibitor significantly potentiated the cGMP signals generated by sGC activating compounds such as BAY 58-2667 or 5-cyclopropyl-2-[1-(2-fluorobenzyl)-1H-pyrazolo [3,4-b]pyridin-3-yl]pyrimidin-4-ylamine (BAY 41-2272) and induced leftward shifts of the corresponding concentration-response curves. Using our newly generated PDE9 reporter cell line, we could show that BAY 73-6691 is able to efficiently penetrate cells and to inhibit intracellular PDE9 activity

Catalytic activity of nanoalloys from gold and palladium

We present a quantitative study of the catalytic activity of well defined faceted gold palladium nanoalloys which are immobilized on cationic spherical polyelectrolyte brushes. The spherical polyelectrolyte brush particles used as carriers for the nanoalloys consist of a solid polystyrene core onto which cationic polyelectrolyte chains of 2 aminoethylmethacrylate are attached. Au Pd nanoalloy particles with sizes in the range from 1 to 3 nm have been generated which are homogeneously distributed on the surface of the spherical polyelectrolyte brushes. The reduction of 4 nitrophenol has been chosen as a well controlled model reaction allowing us to determine the catalytic activity of the nanoalloys as a function of the Au Pd composition. The absorption behavior was studied by Langmuir Hinshelwood kinetics. We find a pronounced maximum of the catalytic activity at 75 molar Au. A comparison of gold, platinum, palladium and gold palladium alloy nanoparticles is made in terms of Langmuir Hinshelwood kinetics. Density functional calculations for Au Pd clusters with up to 38 atoms show that the density of states at the Fermi level increases with increasing Pd content, and that the highest occupied orbitals are associated with Pd atoms. The calculations confirm that small changes in the atomic arrangement can lead to pronounced changes in the particles electronic properties, indicating that the known importance of surface effects is further enhanced in nanoalloy

Phosphodiesterase 2 Protects against Catecholamine-induced Arrhythmias and Preserves Contractile Function after Myocardial Infarction

International audienceRationale: Phosphodiesterase 2 is a dual substrate esterase, which has the unique property to be stimulated by cGMP, but primarily hydrolyzes cAMP. Myocardial phosphodiesterase 2 is upregulated in human heart failure, but its role in the heart is unknown.Objective: To explore the role of phosphodiesterase 2 in cardiac function, propensity to arrhythmia, and myocardial infarction.Methods and Results: Pharmacological inhibition of phosphodiesterase 2 (BAY 60–7550, BAY) led to a significant positive chronotropic effect on top of maximal β-adrenoceptor activation in healthy mice. Under pathological conditions induced by chronic catecholamine infusions, BAY reversed both the attenuated β-adrenoceptor–mediated inotropy and chronotropy. Conversely, ECG telemetry in heart-specific phosphodiesterase 2-transgenic (TG) mice showed a marked reduction in resting and in maximal heart rate, whereas cardiac output was completely preserved because of greater cardiac contraction. This well-tolerated phenotype persisted in elderly TG with no indications of cardiac pathology or premature death. During arrhythmia provocation induced by catecholamine injections, TG animals were resistant to triggered ventricular arrhythmias. Accordingly, Ca2+-spark analysis in isolated TG cardiomyocytes revealed remarkably reduced Ca2+ leakage and lower basal phosphorylation levels of Ca2+-cycling proteins including ryanodine receptor type 2. Moreover, TG demonstrated improved cardiac function after myocardial infarction.Conclusions: Endogenous phosphodiesterase 2 contributes to heart rate regulation. Greater phosphodiesterase 2 abundance protects against arrhythmias and improves contraction force after severe ischemic insult. Activating myocardial phosphodiesterase 2 may, thus, represent a novel intracellular antiadrenergic therapeutic strategy protecting the heart from arrhythmia and contractile dysfunction

5GNOW: Challenging the LTE Design Paradigms of Orthogonality and Synchronicity

Abstract-LTE and LTE-Advanced have been optimized to deliver high bandwidth pipes to wireless users. The transport mechanisms have been tailored to maximize single cell performance by enforcing strict synchronism and orthogonality within a single cell and within a single contiguous frequency band. Various emerging trends reveal major shortcomings of those design criteria: • The fraction of machine-type-communications (MTC) is growing fast. Transmissions of this kind are suffering from the bulky procedures necessary to ensure strict synchronism. • Collaborative schemes have been introduced to boost capacity and coverage (CoMP), and wireless networks are becoming more and more heterogeneous following the non-uniform distribution of users. Tremendous efforts must be spent to collect the gains and to manage such systems under the premise of strict synchronism and orthogonality. • The advent of the Digital Agenda and the introduction of carrier aggregation are forcing the transmission systems to deal with fragmented spectrum. 5GNOW will question the design targets of LTE and LTEAdvanced having these shortcomings in mind. The obedience of LTE and LTE-Advanced to strict synchronism and orthogonality will be challenged. It will develop new PHY and MAC layer concepts being better suited to meet the upcoming needs with respect to service variety and heterogeneous transmission setups. A demonstrator will be built as Proof-of-Concept relying upon continuously growing capabilities of silicon based processing. Wireless transmission networks following the outcomes of 5GNOW will be better suited to meet the manifoldness of services, device classes and transmission setups being present in envisioned future scenarios like smart cities. The integration of systems relying heavily on MTC, e.g. sensor networks, into the communication network will be eased. The per-user experience will be more uniform and satisfying. To ensure this 5GNOW will contribute to upcoming 5G standardization. First and foremost the need for un-tethered telephony and therefore wireless real-time communication has dominated the success of cordless phones, followed by first generation (1G) of cellular communications. Soon, incorporated in 2G, twoway paging implemented by SMS text messaging became the second killer application. With the success of wireless LAN technology (i.e. IEEE 802.11), http internet browsing, and the widespread market adoption of laptop computers internet data connectivity became interesting for anyone, opening up the opportunity for creating a market for the third killer application in 3G, wireless data connectivity. The logical next step has been the shrinkage of the laptop, merging it with the cellular telephone into todays' smartphones, and offering high bandwidth access to wireless users with the world's information at their fingertips everywhere and everytime. This is the scenario of the current 4G generation with the most prominent example LTE-A (Long Term EvolutionAdvanced). Hence, smartphones are, undoubtedly, in the focus of service architectures for future mobile access networks. Current market trends and future projections indicate that smartphone sales will keep growing and overtook conventional phones [TIA's 2009 to constitute now the lion's share of the global phone market: the smartphone has become a mass market device. Keywords-LTE- The next foreseen killer application is the massive wireless connectivity of machines with other machines, referred to as M2M or the Internet of Things (IoT). During the past years a multitude of wireless M2M applications has been explored, e.g. information dissemination in public transport systems or in manufacturing plants. However, fast deployment of M2M through a simple 'plug and play' connection via cellular networks is not a reality and the commercial success has been somewhat limited, yet. The availability of cellular coverage needs to be combined with simplicity of handling, in both software and hardware aspects, i.e. avoiding having to setup and connect as in a ZigBee or WLAN hot-spot but at the same time allowing longer battery life time and cheap devices. These principles can stimulate subscribers to buy M2M sensors and participate in the collection of monitoring data. M2M can be employed by communities (social network) to share monitoring information about cars, homes an