Direct stimulation of the retina by the method of virtual-quanta for heavy cosmic-ray nuclei

The contribution to the frequency of visual sensations induced in the dark-adapted eye by the virtual photon field was calculated, this field is associated with the heavy nuclei that exist in space beyond the geomagnetic field. In order to determine the probability that the virtual photon field induces a light flash, only the portion of the virtual photon spectrum that corresponds to the known frequency dependence of the sensitivity of human rods to visible light was utilized. The results can be expressed as a curve of the mean frequency of light flashes induced by the absorption of at least R virtual photons versus the threshold number R. The contribution to the light flash frequency from the virtual photon field of heavy cosmic ray nuclei is smaller than that from Cerenkov photons. The flux and energy spectra of galactic cosmic ray nuclei helium to iron were used

Luminosity measurements at LHCb using dimuon pairs produced via elastic two photon fusion.

This note outlines the feasibility of using the elastic two photon process pp$\rightarrow$ p+$\mu^{+}\mu^{-}+p$ to make luminosity measurements at LHCb. The overall efficiency at LHCb for recording and selecting pp$\rightarrow$ p+$\mu^{+}\mu^{-}+p$ events produced within 1.6<$\eta$<5 has been determined using Monte-Carlo to be 0.0587 $\pm$ 0.0008, yielding 5210$\pm$71(stat.) events for an integrated luminosity of 1fb$^{-1}$. The main background processes where dimuons are produced via inelastic two-photon fusion and double Pomeron exchange have been studied using the full LHCb detector simulation while the other background sources, including backgrounds caused by K/$\pi$ mis-identification, have been studied at four vector level. The background is estimated to be (4.1 $\pm$ 0.5(stat.) $\pm$ 0.6(syst.))% of the signal level. Most of this background comes from K/$\pi$ mis-identification, although the largest source of uncertainty in the estimation is due to knowledge of the number of events produced via double Pomeron exchange. Systematic uncertainties on a luminosity measurement at LHCb using this channel are estimated to be ~1% the largest of which are the uncertainty on the predicted cross-section for events containing dimuons produced via double Pomeron exchange, and the knowledge of the trigger and reconstruction efficiency for muons in LHCb

Contaminant removal from enclosed atmospheres by regenerable adsorbents

A system for removing contaminants from spacecraft atmospheres was studied, which utilizes catalyst-impregnated activated carbon followed by in-situ regeneration by low-temperature catalytic oxidation of the adsorbed contaminants. Platinum was deposited on activated carbon by liquid phase impregnation with chloroplatinic acid, followed by drying and high-temperature reduction. Results were obtained for the seven selected spacecraft contaminants by means of three experimental test systems. The results indicate that the contaminants could be removed by oxidation with very little loss in adsorptive capacity. The advantages of a catalyst-impregnated carbon for oxidative regeneration are found to be significant enough to warrent its use

Evaluation of techniques for removal of spacecraft contaminants from activated carbon

Alternative techniques for the regeneration of carbon contaminated with various spacecraft contaminants were evaluated. Four different modes of regeneration were evaluated: (1) thermal desorption via vacuum, (2) thermal desorption via nitrogen purge, (3) in-situ catalytic oxidation of adsorbed contaminants, and (4) in-situ non-catalytic oxidation of adsorbed contaminants

Microdosimetry radiation analysis method and device

Apparatus and method for qualitatively and quantitatively analyzing a complex radiation field are provided. A microdosimetry device is provided having an array of microstructure parallel p-n junctions. Each junction defines a predetermined sensitive volume within which a voltage pulse is produced responsive to incident radiation. Circuitry in communication with the detector array generates digital pulse signals representative of the voltage pulses induced within the sensitive volumes responsive to incident radiation, and further provides a summation of the digital pulses occurring at particular energies. The summations of digital pulses are compared to known energies generated by known ionizing particles in comparable sensitive volumes to generate an dose equivalent estimate. Apparatus and method for calculating the total dose from an incident radiation field may also be included

Strain dependence of bonding and hybridization across the metal-insulator transition of VO2

Soft x-ray spectroscopy is used to investigate the strain dependence of the metal-insulator transition of VO2. Changes in the strength of the V 3d - O 2p hybridization are observed across the transition, and are linked to the structural distortion. Furthermore, although the V-V dimerization is well-described by dynamical mean-field theory, the V-O hybridization is found to have an unexpectedly strong dependence on strain that is not predicted by band theory, emphasizing the relevance of the O ion to the physics of VO2

No-activation theorem for Gaussian nonclassical correlations by Gaussian operations

We study general quantum correlations of continuous variable Gaussian states and their interplay with entanglement. Specifically, we investigate the existence of a quantum protocol activating all nonclassical correlations between the subsystems of an input bipartite continuous variable system, into output entanglement between the system and a set of ancillae. For input Gaussian states, we prove that such an activation protocol cannot be accomplished with Gaussian operations, as the latter are unable to create any output entanglement from an initial separable yet nonclassical state in a worst-case scenario. We then construct a faithful non-Gaussian activation protocol, encompassing infinite-dimensional generalizations of controlled-not gates to generate entanglement between system and ancillae, in direct analogy with the finite-dimensional case. We finally calculate the negativity of quantumness, an operational measure of nonclassical correlations defined in terms of the performance of the activation protocol, for relevant classes of two-mode Gaussian states

Development of an in-line filter to prevent intrusion of NO2 toxic vapors into A/C systems

The hypergolic propellant nitrogen tetroxide (N2O4 or NTO) is routinely used in spacecraft launched at Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS). In the case of a catastrophic failure of the spacecraft, there would be a release of the unspent propellant in the form of a toxic cloud. Inhalation of this material at downwind concentrations which may be as high as 20 parts per million (ppm) for 30 minutes in duration, may produce irritation to the eyes, nose and respiratory tract. Studies at both KSC and CCAS have shown that the indoor concentrations of N2O4 during a toxic release may range from 1 to 15 ppm and depend on the air change rate (ACR) for a particular building and whether or not the air conditioning (A/C) system has been shut down or left in an operating mode. This project was initiated in order to assess how current A/C systems could be easily modified to prevent personnel from being exposed to toxic vapors. A sample system has been constructed to test the ability of several types of filter material to capture the N2O4 vapors prior to their infiltration into the A/C system. Test results will be presented which compare the efficiencies of standard A/C filters, water wash systems, and chemically impregnated filter material in taking toxic vapors out of the incoming air stream

Tools to overcome potential barriers to chlamydia screening in general practice: Qualitative evaluation of the implementation of a complex intervention

Background: Chlamydia trachomatis remains a significant public health problem. We used a complex intervention, with general practice staff, consisting of practice based workshops, posters, computer prompts and testing feedback and feedback to increase routine chlamydia screening tests in under 25 year olds in South West England. We aimed to evaluate how intervention components were received by staff and to understand what determined their implementation into ongoing practice. Methods: We used face-to-face and telephone individual interviews with 29 general practice staff analysed thematically within a Normalisation Process Theory Framework which explores: 1. Coherence (if participants understand the purpose of the intervention); 2. Cognitive participation (engagement with and implementation of the intervention); 3. Collective action (work actually undertaken that drives the intervention forwards); 4. Reflexive monitoring (assessment of the impact of the intervention). Results: Our results showed coherence as all staff including receptionists understood the purpose of the training was to make them aware of the value of chlamydia screening tests and how to increase this in their general practice. The training was described by nearly all staff as being of high quality and responsible for creating a shared understanding between staff of how to undertake routine chlamydia screening. Cognitive participation in many general practice staff teams was demonstrated through their engagement by meeting after the training to discuss implementation, which confirmed the role of each staff member and the use of materials. However several participants still felt unable to discuss chlamydia in many consultations or described sexual health as low priority among colleagues. National targets were considered so high for some general practice staff that they didn’t engage with the screening intervention. Collective action work undertaken to drive the intervention included use of computer prompts which helped staff remember to make the offer, testing rate feedback and having a designated lead. Ensuring patients collected samples when still in the general practice was not attained in most general practices. Reflexive monitoring showed positive feedback from patients and other staff about the value of screening, and feedback about the general practices testing rates helped sustain activity. Conclusions: A complex intervention including interactive workshops, materials to help implementation and feedback can help chlamydia screening testing increase in general practices