Counting Points on Genus 2 Curves with Real Multiplication

We present an accelerated Schoof-type point-counting algorithm for curves of genus 2 equipped with an efficiently computable real multiplication endomorphism. Our new algorithm reduces the complexity of genus 2 point counting over a finite field (\F_{q}) of large characteristic from (\widetilde{O}(\log^8 q)) to (\widetilde{O}(\log^5 q)). Using our algorithm we compute a 256-bit prime-order Jacobian, suitable for cryptographic applications, and also the order of a 1024-bit Jacobian

Testing Hardy nonlocality proof with genuine energy-time entanglement

We show two experimental realizations of Hardy ladder test of quantum nonlocality using energy-time correlated photons, following the scheme proposed by A. Cabello \emph{et al.} [Phys. Rev. Lett. \textbf{102}, 040401 (2009)]. Unlike, previous energy-time Bell experiments, these tests require precise tailored nonmaximally entangled states. One of them is equivalent to the two-setting two-outcome Bell test requiring a minimum detection efficiency. The reported experiments are still affected by the locality and detection loopholes, but are free of the post-selection loophole of previous energy-time and time-bin Bell tests.Comment: 5 pages, revtex4, 6 figure

Origin of Shifts in the Surface Plasmon Resonance Frequencies for Au and Ag Nanoparticles

Origin of shifts in the surface plasmon resonance (SPR) frequency for noble metal (Au, Ag) nanoclusters are discussed in this book chapter. Spill out of electron from the Fermi surface is considered as the origin of red shift. On the other hand, both screening of electrons of the noble metal in porous media and quantum effect of screen surface electron are considered for the observed blue shift in the SPR peak position.Comment: 37 pages, 14 Figures in the submitted book chapter of The Annual Reviews in Plasmonics, edited by Professor Chris D. Geddes. Springer Scinec

The proangiogenic capacity of polymorphonuclear neutrophils delineated by microarray technique and by measurement of neovascularization in wounded skin of CD18-deficient mice

Growing evidence supports the concept that polymorphonuclear neutrophils (PMN) are critically involved in inflammation-mediated angiogenesis which is important for wound healing and repair. We employed an oligonucleotide microarray technique to gain further insight into the molecular mechanisms underlying the proangiogenic potential of human PMN. In addition to 18 known angiogenesis-relevant genes, we detected the expression of 10 novel genes, namely midkine, erb-B2, ets-1, transforming growth factor receptor-beta(2) and -beta(3), thrombospondin, tissue inhibitor of metalloproteinase 2, ephrin A2, ephrin B2 and restin in human PMN freshly isolated from the circulation. Gene expression was confi rmed by the RT-PCR technique. In vivo evidence for the role of PMN in neovascularization was provided by studying neovascularization in a skin model of wound healing using CD18-deficient mice which lack PMN infi ltration to sites of lesion. In CD18-deficient animals, neo- vascularization was found to be signifi cantly compromised when compared with wild- type control animals which showed profound neovascularization within the granulation tissue during the wound healing process. Thus, PMN infiltration seems to facilitate inflammation mediated angiogenesis which may be a consequence of the broad spectrum of proangiogenic factors expressed by these cells. Copyright (c) 2006 S. Karger AG, Basel

The surface science of quasicrystals

The surfaces of quasicrystals have been extensively studied since about 1990. In this paper we review work on the structure and morphology of clean surfaces, and their electronic and phonon structure. We also describe progress in adsorption and epitaxy studies. The paper is illustrated throughout with examples from the literature. We offer some reflections on the wider impact of this body of work and anticipate areas for future development. (Some figures in this article are in colour only in the electronic version

The atomic structure of low-index surfaces of the intermetallic compound InPd

The intermetallic compound InPd (CsCl type of crystal structure with a broad compositional range) is considered as a candidate catalyst for the steam reforming of methanol. Single crystals of this phase have been grown to study the structure of its three low-index surfaces under ultra-high vacuum conditions, using low energy electron diffraction (LEED), X-ray photoemission spectroscopy (XPS), and scanning tunneling microscopy (STM). During surface preparation, preferential sputtering leads to a depletion of In within the top few layers for all three surfaces. The near-surface regions remain slightly Pd-rich until annealing to ∼580 K. A transition occurs between 580 and 660 K where In segregates towards the surface and the near-surface regions become slightly In-rich above ∼660 K. This transition is accompanied by a sharpening of LEED patterns and formation of flat step-terrace morphology, as observed by STM. Several superstructures have been identified for the different surfaces associated with this process. Annealing to higher temperatures (≥750 K) leads to faceting via thermal etching as shown for the (110) surface, with a bulk In composition close to the In-rich limit of the existence domain of the cubic phase. The Pd-rich InPd(111) is found to be consistent with a Pd-terminated bulk truncation model as shown by dynamical LEED analysis while, after annealing at higher temperature, the In-rich InPd(111) is consistent with an In-terminated bulk truncation, in agreement with density functional theory (DFT) calculations of the relative surface energies. More complex surface structures are observed for the (100) surface. Additionally, individual grains of a polycrystalline sample are characterized by micro-spot XPS and LEED as well as low-energy electron microscopy. Results from both individual grains and “global” measurements are interpreted based on comparison to our single crystals findings, DFT calculations and previous literature

Equatorial Pacific coral geochemical records show recent weakening of the Walker Circulation

Equatorial Pacific ocean-atmosphere interactions affect climate globally, and a key component of the coupled system is the Walker Circulation, which is driven by sea surface temperature (SST) gradients across the equatorial Pacific. There is conflicting evidence as to whether the SST gradient and Walker Circulation have strengthened or weakened over the late twentieth century. We present new records of SST and sea surface salinity (SSS) spanning 1959-2010 based on paired measurements of Sr/Ca and δ18O in a massive Porites coral from Butaritari atoll in the Gilbert Islands, Republic of Kiribati, in the central western equatorial Pacific. The records show 2-7 year variability correlated with the El Niño-Southern Oscillation (ENSO) and corresponding shifts in the extent of the Indo-Pacific Warm Pool, and decadal-scale signals related to the Pacific Decadal Oscillation and the Pacific Warm Pool Index. In addition, the Butaritari coral records reveal a small but significant increase in SST (0.39°C) from 1959 to 2010 with no accompanying change in SSS, a trend that persists even when ENSO variability is removed. In contrast, larger increases in SST and SSS are evident in coral records from the equatorial Pacific Line Islands, located east of Butaritari. Taken together, the equatorial Pacific coral records suggest an overall reduction in the east-west SST and SSS gradient over the last several decades, and a recent weakening of the Walker Circulation

Reply to comment by Karnauskas et al. on "Equatorial Pacific coral geochemical records show recent weakening of the Walker circulation"

In our paper describing a new coral record from Butaritari, we hypothesized that comparing the temporal trends in our records to coral records from farther east in the equatorial Pacific may support the evidence for a weakening of a Walker circulation, documented elsewhere in the literature [Power and Smith, 2007; Tokinaga et al., 2012]. Weakening of the Walker circulation is expected under global warming due to an imbalance in the rate of change in different aspects of the hydrological cycle [Vecchi and Soden, 2007]. We thank Karnauskas et al. [2015] for recognizing the value of our Butaritari coral climate reconstruction, and we appreciate their critique of our study. The Karnauskas et al. [2015] analyses strengthen our argument regarding the utility of interisland coral-proxy derived sea surface temperature (SST) gradients as a Walker circulation metric, but we disagree with their interpretation of decadal variability in our records. Here we provide additional analyses, which confirm that our reconstruction [Carilli et al., 2014] shows a long-term weakening of the Walker circulation over 1972-1998. We also document that significant decadal variations in Walker circulation strength, and for particular choices of start and end years over which trends are calculated, are able to show slight Walker strengthening. Overall, we conclude that Walker circulation variations are more nuanced than either our original publication [Carilli et al., 2014] or the subsequent Karnauskas et al. [2015] comment would suggest. Karnauskas et al. [2015] also provide a detailed analysis of Equatorial Undercurrent (EUC) activity near the Gilbert Islands and argue that the EUC does not strongly affect Butaritari. Our original publication did not claim to find significant EUC/Butaritari linkages, and we appreciate the diligence of Karnauskas et al. [2015] for ruling this out as a possibility