Numerical loop quantum cosmology: an overview

A brief review of various numerical techniques used in loop quantum cosmology and results is presented. These include the way extensive numerical simulations shed insights on the resolution of classical singularities, resulting in the key prediction of the bounce at the Planck scale in different models, and the numerical methods used to analyze the properties of the quantum difference operator and the von Neumann stability issues. Using the quantization of a massless scalar field in an isotropic spacetime as a template, an attempt is made to highlight the complementarity of different methods to gain understanding of the new physics emerging from the quantum theory. Open directions which need to be explored with more refined numerical methods are discussed.Comment: 33 Pages, 4 figures. Invited contribution to appear in Classical and Quantum Gravity special issue on Non-Astrophysical Numerical Relativit

Green synthesis of silver nanoparticles using Fagopyrum esculentum starch: antifungal, antibacterial activity and its cytotoxicity

52-63Silver nanoparticles (AgNPs) have been synthesized using Fagopyrum esculentum starch as a stabilizing and reducing agent. This reaction was carried out in an autoclave at 15 psi, 121°C for 20 min. UV-visible spectrum of the colloidal nanoparticles showed the surface plasmon absorption band with maximum absorbance at 418 nm. Interaction between functional groups present in the starch and nanoparticles were analyzed by Fourier-transform infrared spectroscopy (FTIR). Size of the synthesized nanoparticles was found to be in the range of 20-30 nm, as revealed from transmission electron microscopy (TEM). The X-ray diffraction analysis revealed the face-centred cubic (fcc) geometry of silver nanoparticles. The nanoparticles were found to be good antifungal agents against Aspergillus niger. The antibacterial activity of the nanoparticles was also studied. The nanoparticles showed higher inhibitory activity against Gram-negative bacteria (Escherichia coli) than the Gram-positive bacteria (Staphylococcus aureus). These results thus show that F. esculentum starch stabilized AgNPs could be used as a promising antimicrobial agent against bacteria the fungi In vitro cytotoxicity assessment of starch stabilized AgNPs has shown no significant cytotoxic effect on human cervical carcinoma cells lines (HeLa) by MTT assay and AgNPs concentration at 200 ug/ml of showed 86% cell viability

Traumatic Retrobulbar Haemorrhage: Aetio-pathology and management

Retrobulbar haematoma following blunt orbital trauma is a rare,but potentially serious complication, since it can evolve rapidly from visual impairment to permanent loss of vision. This sight-threatening situation most commonly arises from orbital bleeding accompanying undisplaced fractures of the orbital walls, an event that increases the pressure inside theorbit and results in vascular damage to the optic nerve. The clinical presentation includes pain, exophthalmos with proptosis, and internal ophthalmoplegia, with impairment or loss of the pupillary reXex. A thin-layer orbital CT scan is an essential diagnostic aid. Therapy is based on orbitaldecompression, via different surgical approaches, with the intention of reducing the pressure on the nerve and vascular structures inside the orbit. Emergent management is of utmost importance as any delay between the onset of symptoms and treatment can have a significant effect onrecovery

Critical analysis of vendor lock-in and its impact on cloud computing migration: a business perspective

Vendor lock-in is a major barrier to the adoption of cloud computing, due to the lack of standardization. Current solutions and efforts tackling the vendor lock-in problem are predominantly technology-oriented. Limited studies exist to analyse and highlight the complexity of vendor lock-in problem in the cloud environment. Consequently, most customers are unaware of proprietary standards which inhibit interoperability and portability of applications when taking services from vendors. This paper provides a critical analysis of the vendor lock-in problem, from a business perspective. A survey based on qualitative and quantitative approaches conducted in this study has identified the main risk factors that give rise to lock-in situations. The analysis of our survey of 114 participants shows that, as computing resources migrate from on-premise to the cloud, the vendor lock-in problem is exacerbated. Furthermore, the findings exemplify the importance of interoperability, portability and standards in cloud computing. A number of strategies are proposed on how to avoid and mitigate lock-in risks when migrating to cloud computing. The strategies relate to contracts, selection of vendors that support standardised formats and protocols regarding standard data structures and APIs, developing awareness of commonalities and dependencies among cloud-based solutions. We strongly believe that the implementation of these strategies has a great potential to reduce the risks of vendor lock-in

Quench-induced spontaneous currents in rings of ultracold fermionic atoms

We have measured the rate of spontaneous current formation in ring-shaped ensembles of fermionic $^6$Li atoms, following a thermal quench through the BCS superfluid phase transition. For the fastest quenches, the mean square winding number follows a scaling law with exponent $\sigma$ = 0.24(2), in line with predictions of the Kibble-Zurek (KZ) model for mean-field BCS theory. We use a hybrid quench protocol involving simultaneous evaporation and interaction ramps, with a long system lifetime allowing characterization of a different rate of spontaneous current formation in the slow-quench regime, where finite-size effects are important. Comparing our observations to a quasi-1D stochastic Ginzburg-Landau model, we find quantitative agreement for fast quenches, but only qualitative agreement for slow quenches.Comment: 6 pages, 4 figure

Computational Intelligence In CAD/CAM Applications

This paper presents a fundamental, direct, and powerful approach to the surface/surface intersection problem in CAD/CAM applications. The algorithm is designed and implemented in three steps: a) Preprocessing- locate the potentially intersecting sections of the surfaces and decompose the surfaces into surface elements within specified flatness tolerance; b) Intersection- decompose the possibly intersecting pairs of surface elements into continuous surface triangulations to find the approximate intersections between the pairs of surface elements; c) Postprocessing-assemble the intersection primitives into curves of intersection, refine the accuracy of computed intersection points, and compact the intersection curves. This surface/surface intersection algorithm is applicable to the widest class, C°, of parametric surfaces, an enhancement over the existing algorithms applicable to only Ck, k≥ 1, surfaces. This implementation, based on computational intelligence, requires no human interaction for intersection curve pattern recognition

Thermal Phase Fluctuations in Narrow Superfluid Rings

Using matter-wave interference, we have investigated thermal phase fluctuations in narrow coplanar, concentric rings of ultracold fermionic superfluids. We found that the correlation length decreases with number density, consistent with theoretical expectations. We also observed that increasing the coupling between the rings leads to greater overall coherence in the system. The phase fluctuations increased with a change from periodic to closed boundary conditions as we applied a potential barrier at one point in a ring. These results are relevant for the implementation of proposals to utilize ultracold quantum gases in large and elongated circuit-like geometries, especially those that require deterministic preparation and control of quantized circulation states.Comment: 10 pages, 8 figure

Energy-efficient precoding in multicell networks with full-duplex base stations

© 2017, The Author(s). This paper considers multi-input multi-output (MIMO) multicell networks, where the base stations (BSs) are full-duplex transceivers, while uplink and downlink users are equipped with multiple antennas and operate in a half-duplex mode. The problem of interest is to design linear precoders for BSs and users to optimize the network’s energy efficiency. Given that the energy efficiency objective is not a ratio of concave and convex functions, the commonly used Dinkelbach-type algorithms are not applicable. We develop a low-complexity path-following algorithm that only invokes one simple convex quadratic program at each iteration, which converges at least to the local optimum. Numerical results demonstrate the performance advantage of our proposed algorithm in terms of energy efficiency

Panel 4 : Report of the Microbiology Panel

Objective. To perform a comprehensive review of the literature from July 2011 until June 2015 on the virology and bacteriology of otitis media in children. Data Sources. PubMed database of the National Library of Medicine. Review Methods. Two subpanels comprising experts in the virology and bacteriology of otitis media were created. Each panel reviewed the relevant literature in the fields of virology and bacteriology and generated draft reviews. These initial reviews were distributed to all panel members prior to meeting together at the Post-symposium Research Conference of the 18th International Symposium on Recent Advances in Otitis Media, National Harbor, Maryland, in June 2015. A final draft was created, circulated, and approved by all panel members. Conclusions. Excellent progress has been made in the past 4 years in advancing our understanding of the microbiology of otitis media. Numerous advances were made in basic laboratory studies, in animal models of otitis media, in better understanding the epidemiology of disease, and in clinical practice. Implications for Practice. (1) Many viruses cause acute otitis media without bacterial coinfection, and such cases do not require antibiotic treatment. (2) When respiratory syncytial virus, metapneumovirus, and influenza virus peak in the community, practitioners can expect to see an increase in clinical otitis media cases. (3) Biomarkers that predict which children with upper respiratory tract infections will develop otitis media may be available in the future. (4) Compounds that target newly identified bacterial virulence determinants may be available as future treatment options for children with otitis media.Peer reviewe

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