Simple manipulation of a microwave dressed-state ion qubit

Many schemes for implementing quantum information processing require that the atomic states used have a non-zero magnetic moment, however such magnetically sensitive states of an atom are vulnerable to decoherence due to fluctuating magnetic fields. Dressing an atom with an external field is a powerful method of reducing such decoherence [N. Timoney et al., Nature 476, 185], even if the states being dressed are strongly coupled to the environment. We introduce an experimentally simpler method of manipulating such a dressed-state qubit, which allows the implementation of general rotations of the qubit, and demonstrate this method using a trapped ytterbium ion

Doppler-free Yb Spectroscopy with Fluorescence Spot Technique

We demonstrate a simple technique to measure the resonant frequency of the 398.9 nm 1S0 - 1P1 transition for the different Yb isotopes. The technique, that works by observing and aligning fluorescence spots, has enabled us to measure transition frequencies and isotope shifts with an accuracy of 60 MHz. We provide wavelength measurements for the transition that differ from previously published work. Our technique also allows for the determination of Doppler shifted transition frequencies for photoionisation experiments when the atomic beam and laser beam are not perpendicular and furthermore allows us to determine the average velocity of the atoms along the direction of atomic beam

EEG Source Imaging Indices of Cognitive Control Show Associations with Dopamine System Genes.

Cognitive or executive control is a critical mental ability, an important marker of mental illness, and among the most heritable of neurocognitive traits. Two candidate genes, catechol-O-methyltransferase (COMT) and DRD4, which both have a roles in the regulation of cortical dopamine, have been consistently associated with cognitive control. Here, we predicted that individuals with the COMT Met/Met allele would show improved response execution and inhibition as indexed by event-related potentials in a Go/NoGo task, while individuals with the DRD4 7-repeat allele would show impaired brain activity. We used independent component analysis (ICA) to separate brain source processes contributing to high-density EEG scalp signals recorded during the task. As expected, individuals with the DRD4 7-repeat polymorphism had reduced parietal P3 source and scalp responses to response (Go) compared to those without the 7-repeat. Contrary to our expectation, the COMT homozygous Met allele was associated with a smaller frontal P3 source and scalp response to response-inhibition (NoGo) stimuli, suggesting that while more dopamine in frontal cortical areas has advantages in some tasks, it may also compromise response inhibition function. An interaction effect emerged for P3 source responses to Go stimuli. These were reduced in those with both the 7-repeat DRD4 allele and either the COMT Val/Val or the Met/Met homozygous polymorphisms but not in those with the heterozygous Val/Met polymorphism. This epistatic interaction between DRD4 and COMT replicates findings that too little or too much dopamine impairs cognitive control. The anatomic and functional separated maximally independent cortical EEG sources proved more informative than scalp channel measures for genetic studies of brain function and thus better elucidate the complex mechanisms in psychiatric illness

Report for the NGFA-5 project.

The objective of this project is to provide DHS a comprehensive evaluation of the current genomic technologies including genotyping, TaqMan PCR, multiple locus variable tandem repeat analysis (MLVA), microarray and high-throughput DNA sequencing in the analysis of biothreat agents from complex environmental samples. To effectively compare the sensitivity and specificity of the different genomic technologies, we used SNP TaqMan PCR, MLVA, microarray and high-throughput illumine and 454 sequencing to test various strains from B. anthracis, B. thuringiensis, BioWatch aerosol filter extracts or soil samples that were spiked with B. anthracis, and samples that were previously collected during DHS and EPA environmental release exercises that were known to contain B. thuringiensis spores. The results of all the samples against the various assays are discussed in this report

Light-cone gauge Hamiltonian for AdS_4 x CP^3 superstring

It is developed the phase-space formulation for the Type IIA superstring on the AdS_4 x CP^3 background in the kappa-symmetry light-cone gauge for which the light-like directions are taken from the D=3 Minkowski boundary of AdS_4. After fixing bosonic light-cone gauge the superstring Hamiltonian is expressed as a function of the transverse physical variables and in the quadratic approximation corresponds to the light-cone gauge-fixed IIA superstring in flat space.Comment: 12 pages, LaTeX; v2 minor improvements of the text, misprints corrected, reference added; v3: missing terms in Eqs.(8),(53) and (56) adde

Quantitative genetics of gastrointestinal strongyle burden and associated body condition in feral horses

This is the author accepted manuscript. The final version is available on open access from Elsevier via the DOI in this recordVariability in host resistance or tolerance to parasites is nearly ubiquitous, and is of key significance in understanding the evolutionary processes shaping host-parasite interactions. While ample research has been conducted on the genetics of parasite burden in livestock, relatively little has been done in free-living populations. Here, we investigate the sources of (co)variation in strongyle nematode faecal egg count (FEC) and body condition in Sable Island horses, a feral population in which parasite burden has previously been shown to negatively correlate with body condition. We used the quantitative genetic “animal model” to understand the sources of (co)variation in these traits, and tested for impacts of an important spatial gradient in habitat quality on the parameter estimates. Although FEC is significantly heritable (h 2 = 0.43 ± 0.11), there was no evidence for significant additive genetic variation in body condition (h 2 = 0.04 ± 0.07), and therefore there was also no significant genetic covariance between the two traits. The negative phenotypic covariance between these traits therefore does not derive principally from additive genetic effects. We also found that both FEC and body condition increase from east to west across the island, which indicates that the longitudinal environmental gradient is not responsible for the negative phenotypic association observed between these traits. There was also little evidence to suggest that quantitative genetic parameters were biased when an individual’s location along the island’s environmental gradient was not incorporated into the analysis. This research provides new and important insights into the genetic basis and adaptive potential of parasite resistance in free-living animals, and highlights the importance of environmental heterogeneity in modulating host-parasite interactions in wild vertebrate systems.Natural Sciences and Engineering Research Council of CanadaCanada Foundation for InnovationRoyal Society International ExchangeRyan Dubé and Heather Ryan Veterinary and Research FundNSERC-CREATE Host-Parasite Interactions Training ProgramLeverhulme Trus

The impact of providing blood to the scene of an accident on transfusion laboratory practice.

BACKGROUND: Haemorrhage is the leading cause of mortality during trauma. In 2012, London's Air Ambulance introduced Blood on Board (BOB), transfusing group O red cells (RBC) to trauma patients at the scene. OBJECTIVES: This study assessed the impact of BOB on the number of mixed field samples received by the laboratory, the number of group O RBC transfused to non-group O patients and the ratio of RBC to fresh frozen plasma (FFP) transfused in the initial 24 h. METHODS: Three major trauma centres collected data on patients for whom the major haemorrhage protocol was activated between August 2008 and February 2012 pre-BOB and March 2012 and December 2013 post-BOB. RESULTS: A total of 233 trauma patients were identified pre-BOB and 119 post-BOB. There was no significant difference in the percentage of group O units transfused to non-group O patients (75 vs 82%, P = 0·21) or the RBC : FFP ratio (pre-BOB mean 1·6 [interquartile range (IQR) 1·0-2·0]; post-BOB mean 1·7 [IQR 1·1-2·2], P = 0·24). There was no significant difference in the percentage of mixed field samples received (23% vs 27%, P = 0·3). CONCLUSION: The introduction of BOB did not change the proportion of group O RBC transfused or the RBC : FFP ratio; however, the proportion of acceptable samples decreased. This is largely due to an increase in blood samples not received from the post-BOB cohort, which we believe is probably due to patients who died at the scene. We have introduced robust systems to indicate reasons for not obtaining samples

Association of preterm birth with ADHD-like cognitive impairments and additional subtle impairments in attention and arousal malleability

BACKGROUND: Whilst preterm-born individuals have an increased risk of developing attention-deficit/hyperactivity disorder (ADHD), and are reported to have ADHD-like attention and arousal impairments, direct group comparisons are scarce. METHODS: We directly compared preterm-born adolescents (n = 186) to term-born adolescents with ADHD (n = 69), and term-born controls (n = 135), aged 11-23, on cognitive-performance, event-related potential and skin conductance level (SCL) measures associated with attention and arousal. The measures are from baseline and fast-incentive conditions of a four-choice reaction time task, previously shown to discriminate between the individuals with ADHD and controls. We aimed to establish whether preterm-born adolescents show: (a) identical cognitive-neurophysiological impairments to term-born adolescents with ADHD (b) possible additional impairments, and whether (c) the observed impairments correlate with ADHD symptom scores. RESULTS: The preterm group, like the term-born ADHD group, showed increased mean reaction time (MRT) and reaction time variability (RTV) in the baseline condition, and attenuated contingent negative variation (CNV) amplitude (response preparation) in the fast-incentive condition. The preterm group, only, did not show significant within-group adjustments in P3 amplitude (attention allocation) and SCL (peripheral arousal). Dimensional analyses showed that ADHD symptoms scores correlated significantly with MRT, RTV and CNV amplitude only. CONCLUSIONS: We find impairments in cognition and brain function in preterm-born adolescents that are linked to increased ADHD symptoms, as well as further impairments, in lack of malleability in neurophysiological processes. Our findings indicate that such impairments extend at least to adolescence. Future studies should extend these investigations into adulthood