DISCUS: an end-to-end solution for ubiquitous broadband optical access

Fiber to the premises has promised to increase the capacity in telecommunications access networks for well over 30 years. While it is widely recognized that optical-fiber-based access networks will be a necessity in the short- to medium-term future, its large upfront cost and regulatory issues are pushing many operators to further postpone its deployment, while installing intermediate unambitious solutions such as fiber to the cabinet. Such high investment cost of both network access and core capacity upgrade often derives from poor planning strategies that do not consider the necessity to adequately modify the network architecture to fully exploit the cost benefit that a fiber-centric solution can bring. DISCUS is a European Framework 7 Integrated Project that, building on optical-centric solutions such as long-reach passive optical access and flat optical core, aims to deliver a cost-effective architecture for ubiquitous broadband services. DISCUS analyzes, designs, and demonstrates end-to-end architectures and technologies capable of saving cost and energy by reducing the number of electronic terminations in the network and sharing the deployment costs among a larger number of users compared to current fiber access systems. This article describes the network architecture and the supporting technologies behind DISCUS, giving an overview of the concepts and methodologies that will be used to deliver our end-to-end network solution

DISCUS: end-to-end network design for ubiquitous high speed broadband services

Fibre-to-the-premises (FTTP) has been long sought as the ultimate solution to satisfy the demand for broadband access in the foreseeable future, and offer distance-independent data rate within access network reach. However, currently deployed FTTP networks have in most cases only replaced the transmission medium, without improving the overall architecture, resulting in deployments that are only cost efficient in densely populated areas (effectively increasing the digital divide). In addition, the large potential increase in access capacity cannot be matched by a similar increase in core capacity at competitive cost, effectively moving the bottleneck from access to core. DISCUS is a European Integrated Project that, building on optical-centric solutions such as Long-Reach Passive Optical access and flat optical core, aims to deliver a cost-effective architecture for ubiquitous broadband services. One of the key features of the project is the end-to-end approach, which promises to deliver a complete network design and a conclusive analysis of its economic viability

Characterisation of the bacterial and fungal communities associated with different lesion sizes of Dark Spot Syndrome occurring in the Coral Stephanocoenia intersepta

The number and prevalence of coral diseases/syndromes are increasing worldwide. Dark Spot Syndrome (DSS) afflicts numerous coral species and is widespread throughout the Caribbean, yet there are no known causal agents. In this study we aimed to characterise the microbial communities (bacteria and fungi) associated with DSS lesions affecting the coral Stephanocoenia intersepta using nonculture molecular techniques. Bacterial diversity of healthy tissues (H), those in advance of the lesion interface (apparently healthy AH), and three sizes of disease lesions (small, medium, and large) varied significantly (ANOSIM R = 0.052 p,0.001), apart from the medium and large lesions, which were similar in their community profile. Four bacteria fitted into the pattern expected from potential pathogens; namely absent from H, increasing in abundance within AH, and dominant in the lesions themselves. These included ribotypes related to Corynebacterium (KC190237), Acinetobacter (KC190251), Parvularculaceae (KC19027), and Oscillatoria (KC190271). Furthermore, two Vibrio species, a genus including many proposed coral pathogens, dominated the disease lesion and were absent from H and AH tissues, making them candidates as potential pathogens for DSS. In contrast, other members of bacteria from the same genus, such as V. harveyii were present throughout all sample types, supporting previous studies where potential coral pathogens exist in healthy tissues. Fungal diversity varied significantly as well, however the main difference between diseased and healthy tissues was the dominance of one ribotype, closely related to the plant pathogen, Rhytisma acerinum, a known causal agent of tar spot on tree leaves. As the corals’ symbiotic algae have been shown to turn to a darker pigmented state in DSS (giving rise to the syndromes name), the two most likely pathogens are R. acerinum and the bacterium Oscillatoria, which has been identified as the causal agent of the colouration in Black Band Disease, another widespread coral disease

Willingness to pay for multifunctional megaprojects: A stated preference analysis among firms in the Amsterdam Zuidas area

http://hdl.handle.net/1871/1621

Representational predicaments at three Hong Kong sites

Representational predicaments arise when a job incumbent believes that attributions and images assumed by dominant authorities unfavourably ignore, or disproportionately and unfavourably emphasize, aspects of the incumbent\u27s own work and social identity. This is likely to happen when the incumbent does not have a close relationship with a dominant authority, and when power asymmetries give the former relatively little control over which aspects of their work and social identity are made visible or invisible to the latter. We draw on critical incident interviews from three organizations to illustrate a typology of six types of representational predicament: invasive spotlighting, idiosyncratic spotlighting, embedded background work, paradoxical social visibility, standardization of work processes, and standardization of work outputs. We analyse responses to representational predicaments according to whether they entailed exit, voice, loyalty, or neglect. Incumbents tended to respond with loyalty if they felt able and willing to accommodate their work behaviour and/or social identity to the dominant representations, and if there were sufficient compensatory factors, such as intrinsic rewards from the work or solidarity with colleagues. Exit or neglect appeared to reflect the belief that it was impossible to accommodate. Power asymmetries appeared to deter voice. Individual employees with a close and cordial working relationship with a member of a dominant authority group, or who were relationally networked to one, appeared not to experience representational predicaments

Parameter Estimation From Improved Measurements of the Cosmic Microwave Background From QUaD

We evaluate the contribution of cosmic microwave background (CMB) polarization spectra to cosmological parameter constraints. We produce cosmological parameters using high-quality CMB polarization data from the ground-based QUaD experiment and demonstrate for the majority of parameters that there is significant improvement on the constraints obtained from satellite CMB polarization data. We split a multi-experiment CMB data set into temperature and polarization subsets and show that the best-fit confidence regions for the ΛCDM six-parameter cosmological model are consistent with each other, and that polarization data reduces the confidence regions on all parameters. We provide the best limits on parameters from QUaD EE/BB polarization data and we find best-fit parameters from the multi-experiment CMB data set using the optimal pivot scale of k$_{p}$ = 0.013 Mpc$^{–1}$ to be {h$^{2}$Ω$_{c}$, h$^{2}$Ω$_{b}$, H$_{0}$, A$_{s}$, n$_{s}$, τ} = {0.113, 0.0224, 70.6, 2.29 × 10$^{-9}$, 0.960, 0.086}.Astronom

Untreated and enzyme-modified bovine whey products reduce association of Salmonella typhinurim, Escherichia coli O157:H7 and Cronobactermalonaticus (formerly Enterobacter sakazakii) to CaCo-2 cells.

Aims: Adhesion of a micro-organism to a cell surface is often considered to be the first step in pathogenesis. Inhibiting this process may have therapeutic effects in vivo. This study investigates the inhibitory effects of various bovine whey products on the association of Salm. Typhimurium, E. coli O157:H7 and C. malonaticus (formerly Enterobacter sakazakii) to the human CaCo-2 cell line. Invasion of CaCo-2 cells by Salm. Typhimurium and C. malonaticus was also examined. Methods and Results: Infection assays were performed by incubating pathogenic acteria with CaCo-2 cells in the presence of untreated (UT) or enzyme-modified (EM) whey products. Associated micro-organisms were directly quantified by plate counts. Invasion of CaCo-2 cells by Salm. Typhimurium and C. malonaticus in the presence ⁄ absence of test materials was also quantified using gentamicin protection assays. At a concentration of 40 mg ml)1 , some UT whey products reduced association and invasion, but this effect was enhanced following hydrolysis with porcine pancreatic lipase. Conclusions: Both UT and EM sweet whey protein concentrates (WPCs) were found to be particularly effective inhibitors of association and invasion. All EM whey products significantly (P < 0Æ05) inhibited invasion of C. malonaticus into epithelial cells, causing a 2-log reduction in the quantity of these micro-organisms internalized. Significance and Impact of the Study: The present study suggests that whey products can inhibit association to and invasion of CaCo-2 cells by selected micro-organisms and may be useful in the treatment and/or prevention of foodborne infections.ye

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

Population‐based cohort study of outcomes following cholecystectomy for benign gallbladder diseases

Background The aim was to describe the management of benign gallbladder disease and identify characteristics associated with all‐cause 30‐day readmissions and complications in a prospective population‐based cohort. Methods Data were collected on consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing all‐cause 30‐day readmissions and complications were analysed by means of multilevel, multivariable logistic regression modelling using a two‐level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 8909 patients undergoing cholecystectomy from 167 hospitals. Some 1451 cholecystectomies (16·3 per cent) were performed as an emergency, 4165 (46·8 per cent) as elective operations, and 3293 patients (37·0 per cent) had had at least one previous emergency admission, but had surgery on a delayed basis. The readmission and complication rates at 30 days were 7·1 per cent (633 of 8909) and 10·8 per cent (962 of 8909) respectively. Both readmissions and complications were independently associated with increasing ASA fitness grade, duration of surgery, and increasing numbers of emergency admissions with gallbladder disease before cholecystectomy. No identifiable hospital characteristics were linked to readmissions and complications. Conclusion Readmissions and complications following cholecystectomy are common and associated with patient and disease characteristics