Gaugephobic Higgs Signals at the LHC

The Gaugephobic Higgs model provides an interpolation between three different models of electroweak symmetry breaking: Higgsless models, Randall-Sundrum models, and the Standard Model. At parameter points between the extremes, Standard Model Higgs signals are present at reduced rates, and Higgsless Kaluza-Klein excitations are present with shifted masses and couplings, as well as signals from exotic quarks necessary to protect the Zbb coupling. Using a new implementation of the model in SHERPA, we show the LHC signals which differentiate the generic Gaugephobic Higgs model from its limiting cases. These are all signals involving a Higgs coupling to a Kaluza-Klein gauge boson or quark. We identify the clean signal $p p \to W^(i) \to W H$ mediated by a Kaluza-Klein W, which can be present at large rates and is enhanced for even Kaluza-Klein numbers. Due to the very hard lepton coming from the W decay, this signature has little background, and provides a better discovery channel for the Higgs than any of the Standard Model modes, over its entire mass range. A Higgs radiated from new heavy quarks also has large rates, but is much less promising due to very high multiplicity final states.Comment: 16 pages, 8 figure

A novel approach to visibility-space modelling of interferometric gravitational lens observations at high angular resolution

We present a new gravitational lens modelling technique designed to model high-resolution interferometric observations with large numbers of visibilities without the need to pre-average the data in time or frequency. We demonstrate the accuracy of the method using validation tests on mock observations. Using small data sets with $\sim 10^3$ visibilities, we first compare our approach with the more traditional direct Fourier transform (DFT) implementation and direct linear solver. Our tests indicate that our source inversion is indistinguishable from that of the DFT. Our method also infers lens parameters to within 1 to 2 per cent of both the ground truth and DFT, given sufficiently high signal-to-noise ratio (SNR). When the SNR is as low as 5, both approaches lead to errors of several tens of per cent in the lens parameters and a severely disrupted source structure, indicating that this is an issue related to the data quality rather than the modelling technique of choice. We then analyze a large data set with $\sim 10^8$ visibilities and a SNR matching real global Very Long Baseline Interferometry observations of the gravitational lens system MG J0751+2716. The size of the data is such that it cannot be modelled with traditional implementations. Using our novel technique, we find that we can infer the lens parameters and the source brightness distribution, respectively, with an RMS error of 0.25 and 0.97 per cent relative to the ground truth.Comment: Submitted to MNRA

Homeostatic-like plasticity of the primary motor hand area is impaired in focal hand dystonia

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Actin polymerization as a key innate immune effector mechanism to control Salmonella infection.

Salmonellosis is one of the leading causes of food poisoning worldwide. Controlling bacterial burden is essential to surviving infection. Nucleotide-binding oligomerization domain-like receptors (NLRs), such as NLRC4, induce inflammasome effector functions and play a crucial role in controlling Salmonella infection. Inflammasome-dependent production of IL-1β recruits additional immune cells to the site of infection, whereas inflammasome-mediated pyroptosis of macrophages releases bacteria for uptake by neutrophils. Neither of these functions is known to directly kill intracellular salmonellae within macrophages. The mechanism, therefore, governing how inflammasomes mediate intracellular bacterial-killing and clearance in host macrophages remains unknown. Here, we show that actin polymerization is required for NLRC4-dependent regulation of intracellular bacterial burden, inflammasome assembly, pyroptosis, and IL-1β production. NLRC4-induced changes in actin polymerization are physically manifested as increased cellular stiffness, and leads to reduced bacterial uptake, production of antimicrobial molecules, and arrested cellular migration. These processes act in concert to limit bacterial replication in the cell and dissemination in tissues. We show, therefore, a functional link between innate immunity and actin turnover in macrophages that underpins a key host defense mechanism for the control of salmonellosis.Financial support for this work was provided by a Cambridge International Scholarship (to S.M.M.), European Research Council Starting Investigator Grant “LightTouch” 282060 (to J.R.G.), Biotechnology and Biological Sciences Research Council (BBSRC) Grants BB/H003916/1 and BB/K006436/1 and BBSRC Research Development Fellowship BB/ H021930/1 (to C.E.B.)This is the accepted manuscript. The final version is available from PNAS at http://www.pnas.org/content/111/49/17588.abstract

Thresholds for Activation of Rabbit Retinal Ganglion Cells with an Ultrafine, Extracellular Microelectrode

PURPOSE. To determine electrical thresholds required for extracellular activation of retinal ganglion cells as part of a project to develop an epiretinal prosthesis. METHODS. Retinal ganglion cells were recorded extracellularly in retinas isolated from adult New Zealand White rabbits. Electrical current pulses of 100-s duration were delivered to the inner surface of the retina from a 5-m long electrode. In about half of the cells, the point of lowest threshold was found by searching with anodal current pulses; in the other cells, cathodal current pulses were used. RESULTS. Threshold measurements were obtained near the cell bodies of 20 ganglion cells and near the axons of 19 ganglion cells. Both cathodal and anodal stimuli evoked a neural response in the ganglion cells that consisted of a single action potential of near-constant latency that persisted when retinal synaptic transmission was blocked with cadmium chloride. For cell bodies, but not axons, thresholds for both cathodal and anodal stimulation were dependent on the search method used to find the point of lowest threshold. With search and stimulation of matching polarity, cathodal stimuli evoked a ganglion cell response at lower currents (approximately one seventh to one tenth axonal threshold) than did anodal stimuli for both cell bodies and axons. With cathodal search and stimulation, cell body median thresholds were somewhat lower (approximately one half) than the axonal median thresholds. With anodal search and stimulation, cell body median thresholds were approximately the same as axonal median thresholds. CONCLUSIONS. The results suggest that cathodal stimulation should produce lower thresholds, more localized stimulation, and somewhat better selectivity for cell bodies over axons than would anodal stimulation. (Invest Ophthalmol Vis Sci. 2003; 44:3533-3543) DOI:10.1167/iovs.02-1041 O ur ultimate goal is to develop an implantable retinal prosthesis that electrically stimulates the retina to provide some functional vision to patients with advanced retinitis pigmentosa or age-related macular degeneration. Retinitis pigmentosa and age-related macular degeneration are forms of blindness that result in substantial loss of photoreceptors. Although physiological and morphologic changes may take place in the inner retinas of affected patients, 1-5 the opportunity exists for direct electrical excitation of the residual neurons as a means of restoring vision. Stimulation possibilities are either epiretinal (the stimulating points are on the inner surface of the retina) or subretinal (the stimulating points are on the outer surface of the retina, between the neural retina and the underlying pigment epithelium). The goal of the present study was to determine current threshold and increase in threshold with electrode displacement for epiretinal stimulation of retinal ganglion cells. The former can be used to judge the power requirements of a functioning prosthesis and the potential for electrochemical toxicity that occurs as current passes through the metal electrode. The latter can be used to guide the choice of interelectrode spacing and estimate the potential spatial resolution that could be derived from a prosthesis. Another motivation is the desire to achieve selective stimulation of ganglion cell bodies rather than axons en passage, which would presumably enhance the quality of perceptions induced by a retinal prosthesis. Only a few studies 6 -8 have been reported in which the currents needed to stimulate individual ganglion cells in the retina with an epiretinal electrode were investigated, and in none of these studies was the current thresholds of axons compared with cell bodies or the current thresholds measured as a function of electrode distance from the site of activation. Also, with the exception of Grumet et al., 8 relatively large microelectrodes have been used in these studies. A small microelectrode was used in the present study to enable a more precise study of threshold variation with electrode position near a cell body or axon of a ganglion cell. Preliminary portions of this work have been presented elsewhere 9 (Wyatt JL, et al. IOVS 1994;35:ARVO Abstract 593; Rizzo JF, et al. IOVS 1997;38:ARVO Abstract 182). MATERIALS AND METHODS Thirty-two adult New Zealand White rabbits (2-2.5 kg) were used in this study. All experimental procedures were in accordance with institutional guidelines and conformed to the guidelines of the ARVO Statement for the Use of Animals in Ophthalmic and Vision Research. Retinal Preparation The rabbits were sedated by an intraperitoneal injection of urethane (1.6 g/kg) and then received an intravenous injection of pentobarbital sodium (20 mg/kg) for deep anesthesia. Under normal room lighting, an eye was enucleated and hemisected, and the vitreous humor was removed with gentle suction applied to the back of a Pasteur pipet. A strip (Ϸ1 ϫ 2 cm) of inferior retina and attached sclera including the optic nerve head was removed and laid flat, ganglion cell side up, on a 10°inclined platform. The retinal strip was superfused with a solution of 8.9 g/L Ames medium (Sigma-Aldrich, St. Louis, MO), 1.9 g/L NaHCO 3 , and 0.8 g/L D-glucose and saturated with 95% O 2 -5% CO 2 . The solution flowed by gravity over the surface of the retina at a rate of 1.4 to 1.7 mL/min. The temperature of the solution on the retina was maintained at 34°C to 36°C. Diffuse background light (Ϸ1 W/cm 2 at the retina) was present throughout the experiments

Angular Dependence of Neutrino Flux in KM3 Detectors in Low Scale Gravity Models

Cubic kilometer neutrino telescopes are capable of probing fundamental questions of ultra-high energy neutrino interactions. There is currently great interest in neutrino interactions caused by low-scale, extra dimension models. Above 1 PeV the cross section in low scale gravity models rises well above the total Standard Model cross section. We assess the observability of this effect in the 1 PeV - 100 PeV energy range of kilometer-scale detectors with several new points of emphasis that hinge on enhanced neutral current cross sections. A major point is the importance of ``feed-down'' regeneration of upward neutrino flux, driven by new-physics neutral current interactions in the flux evolution equations. Feed-down is far from negligible, and it is essential to include its effect. We then find that the angular distribution of events has high discriminating value in separating models. In particular the ``up-to-down'' ratio between upward and downward-moving neutrino fluxes is a practical diagnostic tool which can discriminate between models in the near future. The slope of the angular distribution, in the region of maximum detected flux, is also substantially different in low-scale gravity and the Standard Model. These observables are only weakly dependent on astrophysical flux uncertainties. We conclude that angular distributions can reveal a breakdown of the Standard Model and probe the new physics beyond, as soon as data become available.Comment: 25 pages, 6 figures, discussion of calculations expanded, references adde

Developing and implementing an integrated delirium prevention system of care:a theory driven, participatory research study

Background: Delirium is a common complication for older people in hospital. Evidence suggests that delirium incidence in hospital may be reduced by about a third through a multi-component intervention targeted at known modifiable risk factors. We describe the research design and conceptual framework underpinning it that informed the development of a novel delirium prevention system of care for acute hospital wards. Particular focus of the study was on developing an implementation process aimed at embedding practice change within routine care delivery. Methods: We adopted a participatory action research approach involving staff, volunteers, and patient and carer representatives in three northern NHS Trusts in England. We employed Normalization Process Theory to explore knowledge and ward practices on delirium and delirium prevention. We established a Development Team in each Trust comprising senior and frontline staff from selected wards, and others with a potential role or interest in delirium prevention. Data collection included facilitated workshops, relevant documents/records, qualitative one-to-one interviews and focus groups with multiple stakeholders and observation of ward practices. We used grounded theory strategies in analysing and synthesising data. Results: Awareness of delirium was variable among staff with no attention on delirium prevention at any level; delirium prevention was typically neither understood nor perceived as meaningful. The busy, chaotic and challenging ward life rhythm focused primarily on diagnostics, clinical observations and treatment. Ward practices pertinent to delirium prevention were undertaken inconsistently. Staff welcomed the possibility of volunteers being engaged in delirium prevention work, but existing systems for volunteer support were viewed as a barrier. Our evolving conception of an integrated model of delirium prevention presented major implementation challenges flowing from minimal understanding of delirium prevention and securing engagement of volunteers alongside practice change. The resulting Prevention of Delirium (POD) Programme combines a multi-component delirium prevention and implementation process, incorporating systems and mechanisms to introduce and embed delirium prevention into routine ward practices. Conclusions: Although our substantive interest was in delirium prevention, the conceptual and methodological strategies pursued have implications for implementing and sustaining practice and service improvements more broadly

Relationship of Race/Ethnicity and Survival after Single Umbilical Cord Blood Transplantation for Adults and Children with Leukemia and Myelodysplastic Syndromes

The relationship of race/ethnicity with outcomes of umbilical cord blood transplantation (UCBT) is not well known. We analyzed the association between race/ethnicity and outcomes of unrelated single UCBT for leukemia and myelodysplastic syndromes. Our retrospective cohort study consisted of 885 adults and children (612 whites, 145 blacks, and 128 Hispanics) who received unrelated single UCBT for leukemia and myelodysplastic syndromes between 1995 and 2006 and were reported to the Center for International Blood and Marrow Transplant Research. A 5-6/6 HLA-matched unit with a total nucleated cell count infused of ≥2.5 × 107/kg was given to 40% white and 42% Hispanic, but only 21% black patients. Overall survival at 2 years was 44% for whites, 34% for blacks, and 46% for Hispanics (P = .008). In multivariate analysis adjusting for patient, disease, and treatment factors (including HLA match and cell dose), blacks had inferior overall survival (relative risk of death, 1.31; P = .02), whereas overall survival of Hispanics was similar (relative risk, 1.03; P = .81) to that of whites. For all patients, younger age, early-stage disease, use of units with higher cell dose, and performance status ≥80 were independent predictors of improved survival. Black patients and white patients infused with well-matched cords had comparable survival; similarly, black and white patients receiving units with adequate cell dose had similar survival. These results suggest that blacks have inferior survival to whites after single UCBT, but outcomes are improved when units with a higher cell dose are used

Photon-Photon and Electron-Photon Colliders with Energies Below a TeV

We investigate the potential for detecting and studying Higgs bosons in $\gamma\gamma$ and $e\gamma$ collisions at future linear colliders with energies below a TeV. Our study incorporates realistic $\gamma\gamma$ spectra based on available laser technology, and NLC and CLIC acceleration techniques. Results include detector simulations. We study the cases of: a) a SM-like Higgs boson based on a devoted low energy machine with $\sqrt{s_{ee}}\le 200$ GeV; b) the heavy MSSM Higgs bosons; and c) charged Higgs bosons in $e\gamma$ collisions.We investigate the potential for detecting and studying Higgs bosons in $\gamma\gamma$ and $e\gamma$ collisions at future linear colliders with energies below a TeV. Our study incorporates realistic $\gamma\gamma$ spectra based on available laser technology, and NLC and CLIC acceleration techniques. Results include detector simulations. We study the cases of: a) a SM-like Higgs boson based on a devoted low energy machine with $\sqrt{s_{ee}}\le 200$ GeV; b) the heavy MSSM Higgs bosons; and c) charged Higgs bosons in $e\gamma$ collisions