The power of VNA-driven quasi-optics to sense group molecular action in condensed phase systems

© © 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The authors would like to thank the Engineering and Physical Sciences Research Council (EPSRC, UK) for generous support (EP/1014845)

The power of VNA-driven quasi-optics to sense group molecular action in condensed phase systems

© 2014 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The versatility for quasi-optical circuits, driven by modern vector network analysers, is demonstrated for the purpose of low energy (meV) coherent spectroscopy. One such example is shown applied to the curing dynamics of a non-mercury-based dental cement. This highlights the special place the methodology holds as a `soft-probe' to reveal the time-resolved energetics of condensed phased systems as they self-organise to adopt their low energy state

Low Latency Communication Infrastructure for Synchrophasor Applications in Distribution Networks

With the introduction of new power sources, such as distributed renewable energy resources, and loads, such as electric vehicles, electrical distribution networks must accommodate new energy flow patterns in a considerably dynamic environment. This leads to the need for increasing the observability of the grid to enable a series of mission-critical applications such as voltage/congestion control and fault detection/location. The deployment of Phasor Measurement Units appears to be a promising approach, offering high precision grid monitoring. However, while the low delay requirements of such applications raise a significant challenge to the communication infrastructure, there is currently no clear vision on the exact communication technologies and network topologies that could support these requirements. In this paper, we address this challenge by taking a systematic approach on the design of low latency communication infrastructures. Based on a large set of real medium voltage grid topologies from a European distribution network, we first perform a detailed analysis of the communication requirements. Guided by this analysis, we then propose two algorithms, PLeC and BW-PLeC algorithms, for the design of low latency communication infrastructures that enhance the currently available power-line communication technology with newer high-speed communication links at strategic points in the grid to satisfy the delay requirements while reducing deployment costs

Seamless Support of Low Latency Mobile Applications with NFV-Enabled Mobile Edge-Cloud

Emerging mobile multimedia applications, such as augmented reality, have stringent latency requirements and high computational cost. To address this, mobile edge-cloud (MEC) has been proposed as an approach to bring resources closer to users. Recently, in contrast to conventional fixed cloud locations, the advent of network function virtualization (NFV) has, with some added cost due to the necessary decentralization, enhanced MEC with new flexibility in placing MEC services to any nodes capable of virtualizing their resources. In this work, we address the question on how to optimally place resources among NFV-enabled nodes to support mobile multimedia applications with low latency requirement and when to adapt the current resource placements to address workload changes. We first show that the placement optimization problem is NP-hard and propose an online dynamic resource allocation scheme that consists of an adaptive greedy heuristic algorithm and a detection mechanism to identify the time when the system will no longer be able to satisfy the applications' delay requirement. Our scheme takes into account the effect of current existing techniques (i.e., auto-scaling and load balancing). We design and implement a realistic NFV-enabled MEC simulated framework and show through extensive simulations that our proposal always manages to allocate sufficient resources on time to guarantee continuous satisfaction of the application latency requirements under changing workload while incurring up to 40% less cost in comparison to existing overprovisioning approaches

Toxic metal enrichment and boating intensity: sediment records of antifoulant copper in shallow lakes of eastern England

Tributyltin (TBT), an aqueous biocide derived from antifouling paint pollution, is known to have impacted coastal marine ecosystems, and has been reported in the sediment of the Norfolk and Suffolk Broads, a network of rivers and shallow lakes in eastern England. In the marine environment, the 1987 TBT ban has resulted in expanded use of alternative biocides, raising the question of whether these products too have impacted the Broads ecosystem and freshwaters in general. Here we examine the lake sediment record in the Norfolk and Suffolk Broads for contamination by copper (Cu) (as an active biocide agent) and zinc (Zn) (as a component of booster biocides), to assess their occurrence and potential for causing environmental harm in freshwater ecosystems. We find that, after the introduction of leisure boating, there is a statistically significant difference in Cu enrichment between heavily and lightly boated sites, while no such difference exists prior to this time. At the heavily boated sites the onset of Cu enrichment coincides with a period of rapid increase in leisure boating. Such enrichment is maintained to the present day, with some evidence of continued increase. We conclude that Cu-based antifouling has measurably contaminated lakes exposed to boating, at concentrations high enough to cause ecological harm. Similar findings can be expected at other boated freshwater ecosystems elsewhere in the world

Spectral weight transfer in a disorder-broadened Landau level

In the absence of disorder, the degeneracy of a Landau level (LL) is $N=BA/\phi_0$, where $B$ is the magnetic field, $A$ is the area of the sample and $\phi_0=h/e$ is the magnetic flux quantum. With disorder, localized states appear at the top and bottom of the broadened LL, while states in the center of the LL (the critical region) remain delocalized. This well-known phenomenology is sufficient to explain most aspects of the Integer Quantum Hall Effect (IQHE) [1]. One unnoticed issue is where the new states appear as the magnetic field is increased. Here we demonstrate that they appear predominantly inside the critical region. This leads to a certain ``spectral ordering'' of the localized states that explains the stripes observed in measurements of the local inverse compressibility [2-3], of two-terminal conductance [4], and of Hall and longitudinal resistances [5] without invoking interactions as done in previous work [6-8].Comment: 5 pages 3 figure

Inhibition of Aldose Reductase Prevents Experimental Allergic Airway Inflammation in Mice

The bronchial asthma, a clinical complication of persistent inflammation of the airway and subsequent airway hyper-responsiveness, is a leading cause of morbidity and mortality in critically ill patients. Several studies have shown that oxidative stress plays a key role in initiation as well as amplification of inflammation in airways. However, still there are no good anti-oxidant strategies available for therapeutic intervention in asthma pathogenesis. Most recent studies suggest that polyol pathway enzyme, aldose reductase (AR), contributes to the pathogenesis of oxidative stress-induced inflammation by affecting the NF-kappaB-dependent expression of cytokines and chemokines and therefore inhibitors of AR could be anti-inflammatory. Since inhibitors of AR have already gone through phase-III clinical studies for diabetic complications and found to be safe, our hypothesis is that AR inhibitors could be novel therapeutic drugs for the prevention and treatment of asthma. Hence, we investigated the efficacy of AR inhibition in the prevention of allergic responses to a common natural airborne allergen, ragweed pollen that leads to airway inflammation and hyper-responsiveness in a murine model of asthma.Primary Human Small Airway Epithelial Cells (SAEC) were used to investigate the in vitro effects of AR inhibition on ragweed pollen extract (RWE)-induced cytotoxic and inflammatory signals. Our results indicate that inhibition of AR prevents RWE -induced apoptotic cell death as measured by annexin-v staining, increase in the activation of NF-kappaB and expression of inflammatory markers such as inducible nitric oxide synthase (iNOS), cycloxygenase (COX)-2, Prostaglandin (PG) E(2), IL-6 and IL-8. Further, BALB/c mice were sensitized with endotoxin-free RWE in the absence and presence of AR inhibitor and followed by evaluation of perivascular and peribronchial inflammation, mucin production, eosinophils infiltration and airway hyperresponsiveness. Our results indicate that inhibition of AR prevents airway inflammation and production of inflammatory cytokines, accumulation of eosinophils in airways and sub-epithelial regions, mucin production in the bronchoalveolar lavage fluid and airway hyperresponsiveness in mice.These results suggest that airway inflammation due to allergic response to RWE, which subsequently activates oxidative stress-induced expression of inflammatory cytokines via NF-kappaB-dependent mechanism, could be prevented by AR inhibitors. Therefore, inhibition of AR could have clinical implications, especially for the treatment of airway inflammation, a major cause of asthma pathogenesis