A study of the correlations between jet quenching observables at RHIC

Focusing on four types of correlation plots, $R_{\rm AA}$ vs. $v_2$, $R_{\rm AA}$ vs. $I_{\rm AA}$, $I_{\rm AA}$ vs. $v_2^{I_{\rm AA}}$ and $v_2$ vs.\ $v_2^{I_{\rm AA}}$, we demonstrate how the centrality dependence of \emph{correlations} between multiple jet quenching observables provide valuable insight into the energy loss mechanism in a quark-gluon plasma. In particular we find that a qualitative energy loss model gives a good description of $R_{\rm AA}$ vs.\ $v_2$ only when we take $\Delta E\sim l^3$ and a medium geometry generated by a model of the Color Glass Condensate. This same $\Delta E\sim l^3$ model also qualitatively describes the trigger $p_T$ dependence of $R_{\rm AA}$ vs.\ $I_{\rm AA}$ data and makes novel predictions for the centrality dependence for this $R_{\rm AA}$ vs.\ $I_{\rm AA}$ correlation. Current data suggests, albeit with extremely large uncertainty, that $v_2^{I_{\rm AA}}\gg v_2$, a correlation that is difficult to reproduce in current energy loss models.Comment: 6 pages, 6 figure

Representation of SO(3) Group by a Maximally Entangled State

A representation of the SO(3) group is mapped into a maximally entangled two qubit state according to literatures. To show the evolution of the entangled state, a model is set up on an maximally entangled electron pair, two electrons of which pass independently through a rotating magnetic field. It is found that the evolution path of the entangled state in the SO(3) sphere breaks an odd or even number of times, corresponding to the double connectedness of the SO(3) group. An odd number of breaks leads to an additional $\pi$ phase to the entangled state, but an even number of breaks does not. A scheme to trace the evolution of the entangled state is proposed by means of entangled photon pairs and Kerr medium, allowing observation of the additional $\pi$ phase.Comment: 4 pages, 3 figure

Coherence-Pattern Guided Compressive Sensing with Unresolved Grids

Highly coherent sensing matrices arise in discretization of continuum imaging problems such as radar and medical imaging when the grid spacing is below the Rayleigh threshold. Algorithms based on techniques of band exclusion (BE) and local optimization (LO) are proposed to deal with such coherent sensing matrices. These techniques are embedded in the existing compressed sensing algorithms such as Orthogonal Matching Pursuit (OMP), Subspace Pursuit (SP), Iterative Hard Thresholding (IHT), Basis Pursuit (BP) and Lasso, and result in the modified algorithms BLOOMP, BLOSP, BLOIHT, BP-BLOT and Lasso-BLOT, respectively. Under appropriate conditions, it is proved that BLOOMP can reconstruct sparse, widely separated objects up to one Rayleigh length in the Bottleneck distance {\em independent} of the grid spacing. One of the most distinguishing attributes of BLOOMP is its capability of dealing with large dynamic ranges. The BLO-based algorithms are systematically tested with respect to four performance metrics: dynamic range, noise stability, sparsity and resolution. With respect to dynamic range and noise stability, BLOOMP is the best performer. With respect to sparsity, BLOOMP is the best performer for high dynamic range while for dynamic range near unity BP-BLOT and Lasso-BLOT with the optimized regularization parameter have the best performance. In the noiseless case, BP-BLOT has the highest resolving power up to certain dynamic range. The algorithms BLOSP and BLOIHT are good alternatives to BLOOMP and BP/Lasso-BLOT: they are faster than both BLOOMP and BP/Lasso-BLOT and shares, to a lesser degree, BLOOMP's amazing attribute with respect to dynamic range. Detailed comparisons with existing algorithms such as Spectral Iterative Hard Thresholding (SIHT) and the frame-adapted BP are given

Observations of HONO by laser-induced fluorescence at the South Pole during ANTCI 2003

Observations of nitrous acid (HONO) by laser-induced fluorescence (LIF) at the South Pole taken during the Antarctic Troposphere Chemistry Investigation (ANTCI), which took place over the time period of Nov. 15, 2003 to Jan. 4, 2004, are presented here. The median observed mixing ratio of HONO 10 m above the snow was 5.8 pptv (mean value 6.3 pptv) with a maximum of 18.2 pptv on Nov 30th, Dec 1st, 3rd, 15th, 17th, 21st, 22nd, 25th, 27th and 28th. The measurement uncertainty is ±35%. The LIF HONO observations are compared to concurrent HONO observations performed by mist chamber/ion chromatography (MC/IC). The HONO levels reported by MC/IC are about 7.2 ± 2.3 times higher than those reported by LIF. Citation: Liao, W., A. T. Case, J. Mastromarino, D. Tan, and J. E. Dibb (2006), Observations of HONO by laser-induced fluorescence at the South Pole during ANTCI 2003, Geophys. Res. Lett., 33, L09810, doi:10.1029/2005GL025470

Quenching and Tomography from RHIC to LHC

We compare fully perturbative and fully nonperturbative pictures of high-pT energy loss calculations to the first results from LHC. While over-suppressed compared to published ALICE data, parameter-free pQCD predictions based on the WHDG energy loss model constrained to RHIC data simultaneously describe well the preliminary CMS hadron suppression, ATLAS charged hadron v2, and ALICE D meson suppression; we also provide for future reference WHDG predictions for B meson RAA. However, energy loss calculations based on AdS/CFT also qualitatively describe well the RHIC pion and non-photonic electron suppression and LHC charged hadron suppression. We propose the double ratio of charm to bottom quark RAA will qualitatively distinguish between these two energy loss pictures.Comment: 4 pages, 3 figures. Proceedings for Quark Matter 201

USE OF GENETICALLY MODIFIED SACCHAROMYCES CEREVISIAE TO CONVERT SOLUBLE STARCH DIRECTLY TO BIOETHANOL

Ethanol can be used as a complete fuel or as an octane enhancer, and has the advantages of being renewable and environmentally friendly. Ethanol produced by a fermentation process, generally referred to as bioethanol, is considered to be a partial solution to the worldwide energy crisis. Traditionally, industrial bioethanol fermentation involves two major steps: starch hydrolysis and fermentation. Since the key microorganism, Saccharomyces cerevisiae, lacks amylolytic activity and is unable to directly utilize starch for proliferation and fermentation, it requires intensive amount of energy and pure starch hydrolyzing enzymes to gelatinize, liquefy and dextrinize the raw starch before fermentation. It has been suggested that genetically engineered yeast which expresses amylolytic enzymes could potentially perform simultaneous starch hydrolysis and fermentation. This improvement could greatly reduce the capital and energy costs in current bioethanol producing plants and make bioethanol production more economical. In this project, a novel yeast strain of Saccharomyces cerevisiae was genetically engineered in such a way that barley alpha-amylase was constitutively expressed and immobilized on the yeast cell surface. This particular alpha-amylase was selected based on its superior kinetic properties and its pH optimum which is compatible with the pH of yeast culture media. The cDNA encoding barley alpha-amylase, with a secretion signal sequence, was fused to the cDNA encoding the C-terminal half of a cell wall anchoring protein, alpha-agglutinin. The fusion gene was cloned downstream of a constitutive promoter ADH1 in a yeast episomal plasmid pAMY. The constructed plasmid, pAMY, also contains ampicillin and blasticidin resistance genes for selection of the plasmid harbouring clones in E. coli and yeast, respectively. By developing a starch plate assay, in which clear haloes formed around the successful colonies on a YPD-starch agar plate after staining with iodine vapour, it was shown pAMY harbouring yeast demonstrated detectable amylolytic activity. In addition, cell suspensions of pAMY harbouring yeast were incubated with 1% soluble starch in 16 mM sodium acetate buffer, pH 4.5, 45°C. The majority of soluble starch was converted into maltose within 6 hours and alpha-amylase activity was detected only in the cell pellet fraction and not in the culture supernatant. In batch fermentation studies using 2% soluble wheat starch as sole carbon source, even though pAMY harbouring yeast was able to hydrolyse 75% of soluble starch in 160 hours under the fermentation conditions, no ethanol was produced. This was felt to be due to insufficient alpha-amylase activity which resulted from the enzyme being anchored on the cell wall by alpha-agglutinin. Also, plasmid stability of pAMY harbouring yeast without the presence of selecting antibiotics was studied during batch fermentation experiments. The results suggest that soluble starch may positively select plasmid harbouring yeast cells to stabilize the population of plasmid harbouring cells over plasmid free cells in the fermentor during prolonged batch fermentation. Further research using alternative cell surface anchoring systems are being planned to produce yeast with high ethanol yields for industrial applications

Characterization of sensory neuron membrane proteins (SNMPs) in cotton bollworm Helicoverpa armigera (Lepidoptera: Noctuidae)

Sensory neuron membrane proteins (SNMPs) play a critical role in insect chemosensory system. Previously, three SNMPs were identified, characterized and functionally investigated in a lepidopteran model insect, Bombyx mori . However, whether these results are consistent across other lepidopteran species are unknown. Here genome and transcriptome data analysis, expression profiling, quantitative real‐time PCR (qRT‐PCR) and the yeast hybridization system were utilized to examine snmp genes of Helicoverpa armigera , one of the most destructive lepidopteran pests in cropping areas. In silico expression and qRT‐PCR analyses showed that, just as the B. mori snmp genes, H. armigera snmp1 (Harmsnmp1 ) is specifically expressed in adult antennae. Harmsnmp2 is broadly expressed in multiple tissues including adult antennae, tarsi, larval antennae and mouthparts. Harmsnmp3 is specifically expressed in larval midguts. Further RNAseq analysis suggested that the expression levels of Harmsnmp2 and Harmsnmp3 differed significantly depending on the plant species on which the larvae fed, indicating they may be involved in plant‐feeding behaviours. Yeast hybridization results revealed a protein–protein interaction between HarmSNMP1 and the sex pheromone receptor, HarmOR13. This study demonstrated that SNMPs may share same functions and mechanisms in different lepidopteran species, which improved our understanding of insect snmp genes and their functions in lepidopterans

ASTROD, ASTROD I and their gravitational-wave sensitivities

ASTROD (Astrodynamical Space Test of Relativity using Optical Devices) is a mission concept with three spacecraft -- one near L1/L2 point, one with an inner solar orbit and one with an outer solar orbit, ranging coherently with one another using lasers to test relativistic gravity, to measure the solar system and to detect gravitational waves. ASTROD I with one spacecraft ranging optically with ground stations is the first step toward the ASTROD mission. In this paper, we present the ASTROD I payload and accelerometer requirements, discuss the gravitational-wave sensitivities for ASTROD and ASTROD I, and compare them with LISA and radio-wave PDoppler-tracking of spacecraft.Comment: presented to the 5th Edoardo Amaldi Conference (July 6-11, 2003) and submitted to Classical and Quantum Gravit