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1. Molecular characterization of Enterobacteriaceae resistant to carbapenem antimicrobials

Author

Jaciane B. Marques, Pauline C. Bonez, Vanessa A. Agertt, Vanessa C. Flores, Tanise V. Dalmolin, Grazielle G. Rossi, Nara Lucia F. Dal Forno, Bianca V. Bianchini, Caren R. Mizdal, Fallon S. Siqueira, Roselene A. Righi, Bettina H. Meneghetti, Priscila A. Trindade, Roberto C. V. Santos, and Marli M. A. Campos

Subjects
enterobactérias, carbapenemases, métodos fenotípicos, métodos moleculares, Pathology, RB1-214
Abstract

ABSTRACT The present study aimed to genotypically and phenotypically characterize clinical isolates of carbapenem-resistant Enterobacteriaceae collected from inpatients at the University Hospital of Santa Maria, during seven months. Among the clinical isolates subjected to the modified Hodge test (MHT), 62.5% were positive, indicating possible production of carbapenemase. Polymerase chain reaction (PCR) demonstrated that blaKPC was the most frequently found gene (31%), followed by blaIMP (12.5%). Combined use of the methods is needed to identify carbapenem resistance in enterobacteria to prevent their spread and control the infections caused by these organisms.

Published
2015
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3. Extending light WIMP searches to single scintillation photons in LUX

Author

Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Baxter, A., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Boxer, B., Brás, P., Burdin, S., Byram, D., Cahn, S. B., Carmona-Benitez, M. C., Chan, C., Chiller, A. A., Chiller, C., Currie, A., Cutter, J. E., de Viveiros, L., Dobi, A., Dobson, J. E. Y., Druszkiewicz, E., Edwards, B. N., Faham, C. H., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Gehman, V. M., Genovesi, J., Ghag, C., Gibson, K. R., Gilchriese, M. G. D., Grace, E., Gwilliam, C., Hall, C. R., Hanhardt, M., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Jahangir, O., Ji, W., Kamdin, K., Kazka, K., Khaitan, D., Knoche, R., Korolkova, E. V., Kravitz, S., Kudryavtsev, V. A., Larsen, N. A., Leason, E., Lee, C., Lenardo, B. G., Lesko, K. T., Levy, C., Liao, J., Lin, J., Lindote, A., Lopes, M. I., López-Paredes, B., Manalaysay, A., Mannino, R. L., Marangou, N., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Naylor, A., Nehrkorn, C., Nelson, H. N., Neves, F., Nilima, A., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Reichhart, L., Riffard, Q., Rischbieter, G. R. C., Rossiter, P., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Stephenson, S., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, R., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Utku, U., Uvarov, S., Vacheret, A., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Woodward, D., Xu, J., Yazdani, K., Young, S. K., and Zhang, C.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract

We present a novel analysis technique for liquid xenon time projection chambers that allows for a lower threshold by relying on events with a prompt scintillation signal consisting of single detected photons. The energy threshold of the LUX dark matter experiment is primarily determined by the smallest scintillation response detectable, which previously required a 2-fold coincidence signal in its photomultiplier arrays, enforced in data analysis. The technique presented here exploits the double photoelectron emission effect observed in some photomultiplier models at vacuum ultraviolet wavelengths. We demonstrate this analysis using an electron recoil calibration dataset and place new constraints on the spin-independent scattering cross section of weakly interacting massive particles (WIMPs) down to 2.5 GeV/c$^2$ WIMP mass using the 2013 LUX dataset. This new technique is promising to enhance light WIMP and astrophysical neutrino searches in next-generation liquid xenon experiments.

Published
2019
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4. Improved Measurements of the \b{eta}-Decay Response of Liquid Xenon with the LUX Detector

Author

Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Balajthy, J., Baxter, A., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Boxer, B., Brás, P., Burdin, S., Byram, D., Carmona-Benitez, M. C., Chan, C., Cutter, J. E., de Viveiros, L., Druszkiewicz, E., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Gwilliam, C., Hall, C. R., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Jahangir, O., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Korolkova, E. V., Kravitz, S., Kudryavtsev, V. A., Leason, E., Lenardo, B. G., Lesko, K. T., Liao, J., Lin, J., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marangou, N., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Naylor, A., Nehrkorn, C., Nelson, H. N., Neves, F., Nilima, A., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Riffard, Q., Rischbieter, G. R. C., Rhyne, C., Rossiter, P., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, R., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Utku, U., Uvarov, S., Vacheret, A., Velan, V., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Woodward, D., Xu, J., and Zhang, C.

Subjects
Physics - Instrumentation and Detectors, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment
Abstract

We report results from an extensive set of measurements of the \b{eta}-decay response in liquid xenon.These measurements are derived from high-statistics calibration data from injected sources of both $^{3}$H and $^{14}$C in the LUX detector. The mean light-to-charge ratio is reported for 13 electric field values ranging from 43 to 491 V/cm, and for energies ranging from 1.5 to 145 keV.

Published
2019
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5. Results of a Search for Sub-GeV Dark Matter Using 2013 LUX Data

Author

Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Boxer, B., Brás, P., Burdin, S., Byram, D., Carmona-Benitez, M. C., Chan, C., Cutter, J. E., Davison, T. J. R., Druszkiewicz, E., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Gwilliam, C., Hall, C. R., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Jahangir, O., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Korolkova, E. V., Kravitz, S., Kudryavtsev, V. A., Lenardo, B. G., Lesko, K. T., Liao, J., Lin, J., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marangou, N., Marzioni, M. F., McKinsey, D. N., Mei, D. -M., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Naylor, A., Nehrkorn, C., Nelson, H. N., Neves, F., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Riffard, Q., Rischbieter, G. R. C., Rhyne, C., Rossiter, P., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Utku, U., Uvarov, S., Velan, V., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Woodward, D., Xu, J., Yazdani, K., and Zhang, C.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract

The scattering of dark matter (DM) particles with sub-GeV masses off nuclei is difficult to detect using liquid xenon-based DM search instruments because the energy transfer during nuclear recoils is smaller than the typical detector threshold. However, the tree-level DM-nucleus scattering diagram can be accompanied by simultaneous emission of a Bremsstrahlung photon or a so-called "Migdal" electron. These provide an electron recoil component to the experimental signature at higher energies than the corresponding nuclear recoil. The presence of this signature allows liquid xenon detectors to use both the scintillation and the ionization signals in the analysis where the nuclear recoil signal would not be otherwise visible. We report constraints on spin-independent DM-nucleon scattering for DM particles with masses of 0.4-5 GeV/c$^2$ using 1.4$\times10^4$ kg$\cdot$day of search exposure from the 2013 data from the Large Underground Xenon (LUX) experiment for four different classes of mediators. This analysis extends the reach of liquid xenon-based DM search instruments to lower DM masses than has been achieved previously.

Published
2018
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6. Search for annual and diurnal rate modulations in the LUX experiment

Author

Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Boxer, B., Brás, P., Burdin, S., Byram, D., Carmona-Benitez, M. C., Chan, C., Cutter, J. E., Davison, T. J. R., Druszkiewicz, E., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Gwilliam, C., Hall, C. R., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Korolkova, E. V., Kravitz, S., Kudryavtsev, V. A., Lenardo, B. G., Lesko, K. T., Liao, J., Lin, J., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marangou, N., Marzioni, M. F., McKinsey, D. N., Mei, D. -M., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Rischbieter, G. R. C., Rhyne, C., Rossiter, P., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Utku, U., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Woodward, D., Xu, J., Yazdani, K., and Zhang, C.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract

Various dark matter models predict annual and diurnal modulations of dark matter interaction rates in Earth-based experiments as a result of the Earth's motion in the halo. Observation of such features can provide generic evidence for detection of dark matter interactions. This paper reports a search for both annual and diurnal rate modulations in the LUX dark matter experiment using over 20 calendar months of data acquired between 2013 and 2016. This search focuses on electron recoil events at low energies, where leptophilic dark matter interactions are expected to occur and where the DAMA experiment has observed a strong rate modulation for over two decades. By using the innermost volume of the LUX detector and developing robust cuts and corrections, we obtained a stable event rate of 2.3$\pm$0.2~cpd/keV$_{\text{ee}}$/tonne, which is among the lowest in all dark matter experiments. No statistically significant annual modulation was observed in energy windows up to 26~keV$_{\text{ee}}$. Between 2 and 6~keV$_{\text{ee}}$, this analysis demonstrates the most sensitive annual modulation search up to date, with 9.2$\sigma$ tension with the DAMA/LIBRA result. We also report no observation of diurnal modulations above 0.2~cpd/keV$_{\text{ee}}$/tonne amplitude between 2 and 6~keV$_{\text{ee}}$., Comment: 12 pages, 9 figures

Published
2018
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7. LUX Trigger Efficiency

Author

Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Boxer, B., Brás, P., Burdin, S., Byram, D., Carmona-Benitez, M. C., Chan, C., Cutter, J. E., Davison, T. J. R., Druszkiewicz, E., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Grace, E., Gwilliam, C., Hall, C. R., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Korolkova, E. V., Kravitz, S., Kudryavtsev, V. A., Lenardo, B. G., Lesko, K. T., Liao, J., Lin, J., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marangou, N., Marzioni, M. F., McKinsey, D. N., Mei, D. -M., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Rischbieter, G. R. C., Rhyne, C., Rossiter, P., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Utku, U., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Woodward, D., Xu, J., Yazdani, K., and Zhang, C.

Subjects
Physics - Instrumentation and Detectors
Abstract

The Large Underground Xenon experiment (LUX) searches for dark matter using a dual-phase xenon detector. LUX uses a custom-developed trigger system for event selection. In this paper, the trigger efficiency, which is defined as the probability that an event of interest is selected for offline analysis, is studied using raw data obtained from both electron recoil (ER) and nuclear recoil (NR) calibrations. The measured efficiency exceeds 98\% at a pulse area of 90 detected photons, which is well below the WIMP analysis threshold on the S2 pulse area. The efficiency also exceeds 98\% at recoil energies of \mbox{0.2 keV} and above for ER, and \mbox{1.3 keV} and above for NR. The measured trigger efficiency varies between 99\% and 100\% over the fiducial volume of the detector., Comment: 31 pages, 14 figures

Published
2018
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8. Liquid xenon scintillation measurements and pulse shape discrimination in the LUX dark matter detector

Author

The LUX Collaboration, Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Brás, P., Byram, D., Carmona-Benitez, M. C., Chan, C., Currie, A., Cutter, J. E., Davison, T. J. R., Dobi, A., Druszkiewicz, E., Edwards, B. N., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Hall, C. R., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Lenardo, B. G., Lesko, K. T., Liao, J., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Rhyne, C., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Utku, U., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Xu, J., Yazdani, K., Young, S. K., and Zhang, C.

Subjects
Physics - Instrumentation and Detectors
Abstract

Weakly Interacting Massive Particles (WIMPs) are a leading candidate for dark matter and are expected to produce nuclear recoil (NR) events within liquid xenon time-projection chambers. We present a measurement of the scintillation timing characteristics of liquid xenon in the LUX dark matter detector and develop a pulse shape discriminant to be used for particle identification. To accurately measure the timing characteristics, we develop a template-fitting method to reconstruct the detection times of photons. Analyzing calibration data collected during the 2013-16 LUX WIMP search, we provide a new measurement of the singlet-to-triplet scintillation ratio for electron recoils (ER) below 46~keV, and we make a first-ever measurement of the NR singlet-to-triplet ratio at recoil energies below 74~keV. We exploit the difference of the photon time spectra for NR and ER events by using a prompt fraction discrimination parameter, which is optimized using calibration data to have the least number of ER events that occur in a 50\% NR acceptance region. We then demonstrate how this discriminant can be used in conjunction with the charge-to-light discrimination to possibly improve the signal-to-noise ratio for nuclear recoils., Comment: 16 pages, 11 figures

Published
2018
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9. Calibration, event reconstruction, data analysis and limits calculation for the LUX dark matter experiment

Author

Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Brás, P., Byram, D., Cahn, S. B., Carmona-Benitez, M. C., Chan, C., Currie, A., Cutter, J. E., Davison, T. J. R., Dobi, A., Dobson, J. E. Y., Druszkiewicz, E., Edwards, B. N., Faham, C. H., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Gehman, V. M., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Hall, C. R., Hanhardt, M., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Larsen, N. A., Lee, C., Lenardo, B. G., Lesko, K. T., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Reichhart, L., Rhyne, C., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Xu, J., Yazdani, K., Young, S. K., and Zhang, C.

Subjects
Physics - Instrumentation and Detectors
Abstract

The LUX experiment has performed searches for dark matter particles scattering elastically on xenon nuclei, leading to stringent upper limits on the nuclear scattering cross sections for dark matter. Here, for results derived from ${1.4}\times 10^{4}\;\mathrm{kg\,days}$ of target exposure in 2013, details of the calibration, event-reconstruction, modeling, and statistical tests that underlie the results are presented. Detector performance is characterized, including measured efficiencies, stability of response, position resolution, and discrimination between electron- and nuclear-recoil populations. Models are developed for the drift field, optical properties, background populations, the electron- and nuclear-recoil responses, and the absolute rate of low-energy background events. Innovations in the analysis include in situ measurement of the photomultipliers' response to xenon scintillation photons, verification of fiducial mass with a low-energy internal calibration source, and new empirical models for low-energy signal yield based on large-sample, in situ calibrations.

Published
2017
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10. Position Reconstruction in LUX

Author

LUX Collaboration, Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Brás, P., Byram, D., Cahn, S. B., Carmona-Benitez, M. C., Chan, C., Currie, A., Cutter, J. E., Davison, T. J. R., Dobi, A., Druszkiewicz, E., Edwards, B. N., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Hall, C. R., Hanhardt, M., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Larsen, N. A., Lenardo, B. G., Lesko, K. T., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Rhyne, C., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Xu, J., Yazdani, K., Young, S. K., and Zhang, C.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Physics - Computational Physics
Abstract

The $(x, y)$ position reconstruction method used in the analysis of the complete exposure of the Large Underground Xenon (LUX) experiment is presented. The algorithm is based on a statistical test that makes use of an iterative method to recover the photomultiplier tube (PMT) light response directly from the calibration data. The light response functions make use of a two dimensional functional form to account for the photons reflected on the inner walls of the detector. To increase the resolution for small pulses, a photon counting technique was employed to describe the response of the PMTs. The reconstruction was assessed with calibration data including ${}^{\mathrm{83m}}$Kr (releasing a total energy of 41.5 keV) and ${}^{3}$H ($\beta^-$ with Q = 18.6 keV) decays, and a deuterium-deuterium (D-D) neutron beam (2.45 MeV). In the horizontal plane, the reconstruction has achieved an $(x, y)$ position uncertainty of $\sigma$= 0.82 cm for events of only 200 electroluminescence photons and $\sigma$ = 0.17 cm for 4,000 electroluminescence photons. Such signals are associated with electron recoils of energies $\sim$0.25 keV and $\sim$10 keV, respectively. The reconstructed position of the smallest events with a single electron emitted from the liquid surface has a horizontal $(x, y)$ uncertainty of 2.13 cm., Comment: 30 pages, 17 figures

Published
2017
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11. Ultra-Low Energy Calibration of LUX Detector using $^{127}$Xe Electron Capture

Author

LUX Collaboration, Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Brás, P., Byram, D., Cahn, S. B., Carmona-Benitez, M. C., Chan, C., Currie, A., Cutter, J. E., Davison, T. J. R., Dobi, A., Druszkiewicz, E., Edwards, B. N., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Hall, C. R., Hanhardt, M., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Larsen, N. A., Lenardo, B. G., Lesko, K. T., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Rhyne, C., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Xu, J., Yazdani, K., Young, S. K., and Zhang, C.

Subjects
Physics - Instrumentation and Detectors, Astrophysics - Instrumentation and Methods for Astrophysics, High Energy Physics - Experiment
Abstract

We report an absolute calibration of the ionization yields($\textit{Q$_y$})$ and fluctuations for electronic recoil events in liquid xenon at discrete energies between 186 eV and 33.2 keV. The average electric field applied across the liquid xenon target is 180 V/cm. The data are obtained using low energy $^{127}$Xe electron capture decay events from the 95.0-day first run from LUX (WS2013) in search of Weakly Interacting Massive Particles (WIMPs). The sequence of gamma-ray and X-ray cascades associated with $^{127}$I de-excitations produces clearly identified 2-vertex events in the LUX detector. We observe the K- (binding energy, 33.2 keV), L- (5.2 keV), M- (1.1 keV), and N- (186 eV) shell cascade events and verify that the relative ratio of observed events for each shell agrees with calculations. The N-shell cascade analysis includes single extracted electron (SE) events and represents the lowest-energy electronic recoil $\textit{in situ}$ measurements that have been explored in liquid xenon., Comment: 10 pages, 10 figures, 2 tables

Published
2017
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12. 3D Modeling of Electric Fields in the LUX Detector

Author

LUX Collaboration, Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Brás, P., Byram, D., Cahn, S. B., Carmona-Benitez, M. C., Chan, C., Currie, A., Cutter, J. E., Davison, T. J. R., Dobi, A., Druszkiewicz, E., Edwards, B. N., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Hall, C. R., Hanhardt, M., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Larsen, N. A., Lenardo, B. G., Lesko, K. T., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Rhyne, C., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Xu, J., Yazdani, K., Young, S. K., and Zhang, C.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Physics - Computational Physics
Abstract

This work details the development of a three-dimensional (3D) electric field model for the LUX detector. The detector took data during two periods of searching for weakly interacting massive particle (WIMP) searches. After the first period completed, a time-varying non-uniform negative charge developed in the polytetrafluoroethylene (PTFE) panels that define the radial boundary of the detector's active volume. This caused electric field variations in the detector in time, depth and azimuth, generating an electrostatic radially-inward force on electrons on their way upward to the liquid surface. To map this behavior, 3D electric field maps of the detector's active volume were built on a monthly basis. This was done by fitting a model built in COMSOL Multiphysics to the uniformly distributed calibration data that were collected on a regular basis. The modeled average PTFE charge density increased over the course of the exposure from -3.6 to $-5.5~\mu$C/m$^2$. From our studies, we deduce that the electric field magnitude varied while the mean value of the field of $\sim200$~V/cm remained constant throughout the exposure. As a result of this work the varying electric fields and their impact on event reconstruction and discrimination were successfully modeled.

Published
2017
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13. $^{83\textrm{m}}$Kr calibration of the 2013 LUX dark matter search

Author

LUX Collaboration, Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Brás, P., Byram, D., Cahn, S. B., Carmona-Benitez, M. C., Chan, C., Currie, A., Cutter, J. E., Davison, T. J. R., Dobi, A., Druszkiewicz, E., Edwards, B. N., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Genovesi, J., Ghag, C., Gilchriese, M. G. D., Hall, C. R., Hanhardt, M., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Larsen, N. A., Lenardo, B. G., Lesko, K. T., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Rhyne, C., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Xu, J., Yazdani, K., Young, S. K., and Zhang, C.

Subjects
Physics - Instrumentation and Detectors
Abstract

LUX was the first dark matter experiment to use a $^{83\textrm{m}}$Kr calibration source. In this paper we describe the source preparation and injection. We also present several $^{83\textrm{m}}$Kr calibration applications in the context of the 2013 LUX exposure, including the measurement of temporal and spatial variation in scintillation and charge signal amplitudes, and several methods to understand the electric field within the time projection chamber.

Published
2017
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14. Limits on spin-dependent WIMP-nucleon cross section obtained from the complete LUX exposure

Author

LUX Collaboration, Akerib, D. S., Alsum, S., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Brás, P., Byram, D., Cahn, S. B., Carmona-Benitez, M. C., Chan, C., Chiller, A. A., Chiller, C., Currie, A., Cutter, J. E., Davison, T. J. R., Dobi, A., Dobson, J. E. Y., Druszkiewicz, E., Edwards, B. N., Faham, C. H., Fallon, S. R., Fiorucci, S., Gaitskell, R. J., Gehman, V. M., Ghag, C., Gilchriese, M. G. D., Hall, C. R., Hanhardt, M., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Larsen, N. A., Lee, C., Lenardo, B. G., Lesko, K. T., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Reichhart, L., Rhyne, C., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Stephenson, S., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Xu, J., Yazdani, K., Young, S. K., and Zhang, C.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

We present experimental constraints on the spin-dependent WIMP-nucleon elastic cross sections from the total 129.5 kg-year exposure acquired by the Large Underground Xenon experiment (LUX), operating at the Sanford Underground Research Facility in Lead, South Dakota (USA). A profile likelihood ratio analysis allows 90% CL upper limits to be set on the WIMP-neutron (WIMP-proton) cross section of $\sigma_n$ = 1.6$\times 10^{-41}$ cm$^{2}$ ($\sigma_p$ = 5$\times 10^{-40}$ cm$^{2}$) at 35 GeV$c^{-2}$, almost a sixfold improvement over the previous LUX spin-dependent results. The spin-dependent WIMP-neutron limit is the most sensitive constraint to date., Comment: 7 pages, 3 figures, version accepted by PRL

Published
2017
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15. First Searches for Axions and Axion-Like Particles with the LUX Experiment

Author

Akerib, D. S., Alsum, S., Aquino, C., Araújo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Brás, P., Byram, D., Cahn, S. B., Carmona-Benitez, M. C., Chan, C., Chiller, A. A., Chiller, C., Currie, A., Cutter, J. E., Davison, T. J. R., Dobi, A., Dobson, J. E. Y., Druszkiewicz, E., Edwards, B. N., Faham, C. H., Fallon, S. R., Fiorucci, S., Gaitskell, R. J., Gehman, V. M., Ghag, C., Gibson, K. R., Gilchriese, M. G. D., Hall, C. R., Hanhardt, M., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Ji, W., Kamdin, K., Kazkaz, K., Khaitan, D., Knoche, R., Larsen, N. A., Lee, C., Lenardo, B. G., Lesko, K. T., Lindote, A., Lopes, M. I., Manalaysay, A., Mannino, R. L., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Nehrkorn, C., Nelson, H. N., Neves, F., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Reichhart, L., Rhyne, C., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Stephenson, S., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Uvarov, S., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Xu, J., Yazdani, K., Young, S. K., and Zhang, C.

Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics, High Energy Physics - Phenomenology
Abstract

The first searches for axions and axion-like particles with the Large Underground Xenon (LUX) experiment are presented. Under the assumption of an axio-electric interaction in xenon, the coupling constant between axions and electrons, gAe is tested, using data collected in 2013 with an exposure totalling 95 live-days $\times$ 118 kg. A double-sided, profile likelihood ratio statistic test excludes gAe larger than 3.5 $\times$ 10$^{-12}$ (90% C.L.) for solar axions. Assuming the DFSZ theoretical description, the upper limit in coupling corresponds to an upper limit on axion mass of 0.12 eV/c$^{2}$, while for the KSVZ description masses above 36.6 eV/c$^{2}$ are excluded. For galactic axion-like particles, values of gAe larger than 4.2 $\times$ 10$^{-13}$ are excluded for particle masses in the range 1-16 keV/c$^{2}$. These are the most stringent constraints to date for these interactions.

Published
2017
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17. Xenon Bubble Chambers for Direct Dark Matter Detection

Author

Levy, C., Fallon, S., Genovesi, J., Khaitan, D., Klimov, K., Mock, J., and Szydagis, M.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Physics - Instrumentation and Detectors
Abstract

The search for dark matter is one of today's most exciting fields. As bigger detectors are being built to increase their sensitivity, background reduction is an ever more challenging issue. To this end, a new type of dark matter detector is proposed, a xenon bubble chamber, which would combine the strengths of liquid xenon TPCs, namely event by event energy resolution, with those of a bubble chamber, namely insensitivity to electronic recoils. In addition, it would be the first time ever that a dark matter detector is active on all three detection channels, ionization and scintillation characteristic of xenon detectors, and heat through bubble formation in superheated fluids. Preliminary simulations show that, depending on threshold, a discrimination of 99.99\% to 99.9999+\% can be achieved, which is on par or better than many current experiments. A prototype is being built at the University at Albany, SUNY. The prototype is currently undergoing seals, thermal, and compression testing., Comment: 11 pages, 6 pages, LIDINE 2015 proceeding

Published
2016
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18. Designing the Future of Preservation

Author

Aidoo, Fallon S. and Barber, Daniel A.

Subjects
Global temperature changes, Recycling (Waste, etc.) -- United Kingdom, Environmentalists, Architecture and design industries, History, UNESCO
Abstract

Although ''Reduce, Reuse, Recycle' has served as a catchy public education tool for American environmental activists in the recent past, adaptation of the built environment to the challenges of climate [...]

Published
2021

20. Dopaminergic modulation of planning and attention

Author

Fallon, S. J.

Subjects
616.8
Abstract

This thesis has explored the neurochemical and psychological basis of cognitive heterogeneity, particularly within the domains of planning and attention, and the relationship that deficits in these domains have between each other. The neurochemical basis of these deficits was examined by investigating the extent to which a genetic polymorphism in the Catechol O-methyltransferase (COMT) enzyme, an enzyme thought to modulate PFC dopamine levels, influenced participants’ cognitive performance. This thesis was able to establish that, whilst there appears to be an inverted-U shape function between putative PFC dopamine levels and attention set-formation (a measure of attentional structure), there is no evidence for supposing that such a relationship exists between PFC dopamine levels and planning ability. The psychological basis of cognitive heterogeneity in PD patients was probed by examining ability of PD patients to establish a demarcation between relevant and irrelevant information, and rapidly update this demarcation. Overall, it was found that PD patients did not have generic difficulty in distinguishing between relevant and irrelevant information, or in updating this distinction. Rather, such deficits were only found in certain experimental contexts, further underlying the specificity of attentional impairments in PD. Overall planning performance in PD patients and healthy older adults was not found to predict attentional dysfunction. Thus, there appears to be a separate, or relatively independent, basis for impairment in these two domains.

Published
2010

25. Architectures of mis/managed retreat: Black land loss to green housing gains

Author

Fallon S. Aidoo

Subjects
Environmental justice, Sustainable development, Managed retreat, Scholarship, Flood myth, restrict, Political science, Geography, Planning and Development, Stakeholder, Public administration, Indigenous, General Environmental Science
Abstract

Hurricane Katrina submerged thousands of single-story, slab-on-grade homes in low-lying New Orleans, disproportionately displacing African Americans they sheltered and sustained. Critical disaster studies cast charitable individuals and organizations as sponsors of Black survival, yet nongovernmental aid programs remain marginal to scholarship on environmental justice and Black geographies. This paper sheds light on the funding programs, public-private partnerships, and design-build projects by which philanthropies and charities aid Black, Indigenous and other People of Color (BIPOC) in retreat from flood hazards. This nested case study of HUD’s Neighborhood Stabilization program and the Salvation Army’s EnviRenew program shows Black developers, planners, and architects of retreat from New Orleans’s Pontchartrain Park Historic District gained public, private, and philanthropic sponsors at steep costs: the loss of land, life, and leadership in sustainable development. Drawing on administrative data, legal documents, and stakeholder interviews, the mixed-methods analysis finds new housing built above projected base flood elevations inside flood hazard zones not by choice or by chance, but in compliance with aid programs requiring Black participation in land buyout programs (Road Home) and Black facilitation of green home building and buying (Build Back Better). The Pontchartrain Park case of “management failure,” which included rescinded grants and land takings, not only illuminates the macroeconomics and microaggressions that restrict where and how Black resettlement takes place. Ultimately, this article reveals climate mitigation patrons relocate BIPOC households and heritage from endangered places in theory, yet, in practice, their relief formulas may house marginalized minorities in precarious places above measured risks.

Published
2021

27. Parkinson's Disease and Dopaminergic Therapy--Differential Effects on Movement, Reward and Cognition

Author

Rowe, J. B., Hughes, L., Ghosh, B. C. P., Eckstein, D., Williams-Gray, C. H., Fallon, S., Barker, R. A., and Owen, A. M.

Abstract

Cognitive deficits are very common in Parkinson's disease particularly for "executive functions" associated with frontal cortico-striatal networks. Previous work has identified deficits in tasks that require attentional control like task-switching, and reward-based tasks like gambling or reversal learning. However, there is a complex relationship between the specific cognitive problems faced by an individual patient, their stage of disease and dopaminergic treatment. We used a bimodality continuous performance task during fMRI to examine how patients with Parkinson's disease represent the prospect of reward and switch between competing task rules accordingly. The task-switch was not separately cued but was based on the implicit reward relevance of spatial and verbal dimensions of successive compound stimuli. Nineteen patients were studied in relative "on" and "off" states, induced by dopaminergic medication withdrawal (Hoehn and Yahr stages 1-4). Patients were able to successfully complete the task and establish a bias to one or other dimension in order to gain reward. However the lateral prefrontal cortex and caudate nucleus showed a non-linear U-shape relationship between motor disease severity and regional brain activation. Dopaminergic treatment led to a shift in this U-shape function, supporting the hypothesis of differential neurodegeneration in separate motor and cognitive cortico-striato-thalamo-cortical circuits. In addition, anterior cingulate activation associated with reward expectation declined with more severe disease, whereas activation following actual rewards increased with more severe disease. This may facilitate a change in goal-directed behaviours from deferred predicted rewards to immediate actual rewards, particularly when on dopaminergic treatment. We discuss the implications for investigation and optimal treatment of this common condition at different stages of disease. (Contains 1 table and 4 figures.)

Published
2008
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28. Body Anthropometric Characteristics and Rectal Temperature Cooling Rates in Women With Hyperthermia

Author

Fallon S. Koenig, Kevin C. Miller, Paul O'Connor, and Noshir Amaria

Subjects
Adult, Male, Hot Temperature, Temperature, Water, Physical Therapy, Sports Therapy and Rehabilitation, General Medicine, Hyperthermia, Induced, Body Temperature, Cold Temperature, Young Adult, Cross-Sectional Studies, Immersion, Humans, Orthopedics and Sports Medicine, Female, Exertional Heat Illness, Exercise, Body Temperature Regulation
Abstract

Context Cold-water immersion (CWI) is the best treatment for patients with exertional heat stroke (EHS), and rectal temperature (Trec) cooling rates may differ between sexes. Previous authors have suggested that the body surface area (BSA):lean body mass (LBM) ratio is the largest factor affecting CWI Trec cooling rates in men with hyperthermia; this has never been confirmed in women with hyperthermia. Objective To examine whether the BSA:LBM ratio and other anthropometric characteristics affect Trec cooling rates in women with hyperthermia. Design Cross-sectional study. Setting Laboratory. Patients or Other Participants Sixteen women were placed in either a low BSA:LBM ratio (LOW; n = 8; age = 22 ± 1 years, height = 166.8 ± 6.0 cm, mass = 64.1 ± 4.5 kg, BSA:LBM ratio = 3.759 ± 0.214 m2/kg·102) or high BSA:LBM ratio (HIGH; n = 8; age = 22 ± 2 years, height = 162.7 ± 8.9 cm, mass = 65.8 ± 12.7 kg, BSA:LBM ratio = 4.161 ± 0.232 m2/kg·102) group. Intervention(s) On day 1, we measured physical characteristics using dual-energy x-ray absorptiometry, and participants completed a maximal oxygen consumption test. On day 2, participants walked at 4.8 km/h for 3 minutes and then ran at 80% of their predetermined maximal oxygen consumption for 2 minutes in the heat (temperature = ∼40°C, relative humidity = 40%). This sequence was repeated until Trec reached 39.5°C. Then they underwent CWI (temperature = ∼10°C) until Trec was 38°C. Main Outcome Measure(s) Rectal temperature and CWI cooling rates. Results The groups had different BSA:LBM ratios (P = .001), LBM (LOW: 45.8 ± 3.0 kg; HIGH: 41.0 ± 5.1 kg; P = .02), and body fat percentages (LOW: 25.7% ± 5.0%; HIGH: 33.7% ± 6.3%; P = .007) but not different BSA (LOW: 1.72 ± 0.08 m2; HIGH: 1.70 ± 0.16 m2; P = .40) or body mass index (LOW: 23.1 ± 2.1; HIGH: 24.9 ± 4.7; P = .17). Despite differences in several physical characteristics, Trec cooling rates were excellent but comparable (LOW: 0.26°C/min ± 0.09°C/min; HIGH: 0.27°C/min ± 0.07°C/min; P = .39). The BSA:LBM ratio (r = 0.14, P = .59), BSA (r = −0.01, P = .97), body mass index (r = 0.37, P = .16), and body fat percentage (r = 0.29, P = .28), LBM (r = −0.10, P = .70) were not correlated with Trec cooling rates. Conclusions Body anthropometric characteristics did not affect CWI Trec cooling rates in women with hyperthermia. Therefore, clinicians need not worry that anthropometric characteristics might slow CWI treatment in women with severe hyperthermia.

Published
2022

33. Delayed presentation of food protein-induced enterocolitis syndrome (FPIES) to okra in a toddler

Author

Hunter Hall, Sara Anvari, Fallon Schultz, Olubukola Ojuola, and Nicholas L. Rider

Subjects
Food protein-induced enterocolitis syndrome (FPIES), Non-immunoglobulin E (IgE), Vomiting, Okra, Food allergy, Immunologic diseases. Allergy, RC581-607
Abstract

Abstract Background Food protein-induced enterocolitis syndrome (FPIES) is a non-immunoglobulin E (IgE) -mediated food allergy predominantly observed in infants and characterized by the delayed onset of vomiting following ingestion of a trigger food. An increase in research and clinical consideration of FPIES has led to the discovery of unique deviations from the standard FPIES triggers and presentations. Case presentation A 34-month-old female patient with a history of consuming okra daily presented to medical attention after developing classic FPIES symptoms to okra beginning at 14-months of age. Conclusions Recently, awareness about the varied nature of FPIES clinical presentation has come to light. This case is the first to describe FPIES to the fruit okra that developed over a 12-month time span after previously tolerating the food. This case serves to emphasize the importance of understanding the range of FPIES symptoms to improve recognition and expedite best practice recommendations.

Published
2024
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40. Extending light WIMP searches to single scintillation photons in LUX

Author

Akerib, D. S., Alsum, S., Ara��jo, H. M., Bai, X., Bailey, A. J., Balajthy, J., Baxter, A., Beltrame, P., Bernard, E. P., Bernstein, A., Biesiadzinski, T. P., Boulton, E. M., Boxer, B., Br��s, P., Burdin, S., Byram, D., Cahn, S. B., Carmona-Benitez, M. C., Chan, C., Chiller, A. A., Chiller, C., Currie, A., Cutter, J. E., de Viveiros, L., Dobi, A., Dobson, J. E. Y., Druszkiewicz, E., Edwards, B. N., Faham, C. H., Fallon, S. R., Fan, A., Fiorucci, S., Gaitskell, R. J., Gehman, V. M., Genovesi, J., Ghag, C., Gibson, K. R., Gilchriese, M. G. D., Grace, E., Gwilliam, C., Hall, C. R., Hanhardt, M., Haselschwardt, S. J., Hertel, S. A., Hogan, D. P., Horn, M., Huang, D. Q., Ignarra, C. M., Jacobsen, R. G., Jahangir, O., Ji, W., Kamdin, K., Kazka, K., Khaitan, D., Knoche, R., Korolkova, E. V., Kravitz, S., Kudryavtsev, V. A., Larsen, N. A., Leason, E., Lee, C., Lenardo, B. G., Lesko, K. T., Levy, C., Liao, J., Lin, J., Lindote, A., Lopes, M. I., L��pez-Paredes, B., Manalaysay, A., Mannino, R. L., Marangou, N., Marzioni, M. F., McKinsey, D. N., Mei, D. M., Mock, J., Moongweluwan, M., Morad, J. A., Murphy, A. St. J., Naylor, A., Nehrkorn, C., Nelson, H. N., Neves, F., Nilima, A., O'Sullivan, K., Oliver-Mallory, K. C., Palladino, K. J., Pease, E. K., Reichhart, L., Riffard, Q., Rischbieter, G. R. C., Rossiter, P., Shaw, S., Shutt, T. A., Silva, C., Solmaz, M., Solovov, V. N., Sorensen, P., Stephenson, S., Sumner, T. J., Szydagis, M., Taylor, D. J., Taylor, R., Taylor, W. C., Tennyson, B. P., Terman, P. A., Tiedt, D. R., To, W. H., Tripathi, M., Tvrznikova, L., Utku, U., Uvarov, S., Vacheret, A., Velan, V., Verbus, J. R., Webb, R. C., White, J. T., Whitis, T. J., Witherell, M. S., Wolfs, F. L. H., Woodward, D., Xu, J., Yazdani, K., Young, S. K., Zhang, C., and Science and Technology Facilities Council (STFC)

Subjects
BACKGROUNDS, Photomultiplier, Physics - Instrumentation and Detectors, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Photon, Physics::Instrumentation and Detectors, Dark matter, FOS: Physical sciences, chemistry.chemical_element, Astronomy & Astrophysics, 01 natural sciences, 7. Clean energy, High Energy Physics - Experiment, Physics, Particles & Fields, Nuclear physics, High Energy Physics - Experiment (hep-ex), XENON, Xenon, WIMP, 0103 physical sciences, 010306 general physics, Instrumentation and Methods for Astrophysics (astro-ph.IM), physics.ins-det, Physics, Scintillation, Science & Technology, hep-ex, 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, Instrumentation and Detectors (physics.ins-det), chemistry, Weakly interacting massive particles, Physical Sciences, astro-ph.CO, Neutrino, Astrophysics - Instrumentation and Methods for Astrophysics, EMISSION, Astrophysics - Cosmology and Nongalactic Astrophysics, astro-ph.IM
Abstract

We present a novel analysis technique for liquid xenon time projection chambers that allows for a lower threshold by relying on events with a prompt scintillation signal consisting of single detected photons. The energy threshold of the LUX dark matter experiment is primarily determined by the smallest scintillation response detectable, which previously required a twofold coincidence signal in its photomultiplier arrays, enforced in data analysis. The technique presented here exploits the double photoelectron emission effect observed in some photomultiplier models at vacuum ultraviolet wavelengths. We demonstrate this analysis using an electron recoil calibration dataset and place new constraints on the spin-independent scattering cross section of weakly interacting massive particles (WIMPs) down to 2.5 GeV / c 2 WIMP mass using the 2013 LUX dataset. This new technique is promising to enhance light WIMP and astrophysical neutrino searches in next-generation liquid xenon experiments.

Published
2020

41. Core Stability and Athletic Performance in Male and Female Lacrosse Players

Author

GREENE, FALLON S., PERRYMAN, ERIN, CLEARY, CHRISTOPHER J., and COOK, SUMMER B.

Subjects
Original Research
Abstract

This study determined the relationship of core stability with power production, agility, and dynamic stability of collegiate lacrosse players and whether core stability is more evident in these performance variables in either males or females. Twenty male and female collegiate lacrosse players (20.3 ± 1.0 years, 173.2 ± 11.8 cm, 72.6 ± 13.0 kg) performed the pro-agility shuttle, the countermovement jump (CMJ), the Star Excursion Balance Test (SEBT), and prone, right lateral, and left lateral planks on two sessions-familiarization and testing. Independent T-tests were used to compare sexes. SPSS 24.0 was used; significance was accepted at p < 0.05. Pearson correlations were used to compare the relationship of core stability to the performance variables in participants. There was a significant relationship found between the prone plank and pro-agility shuttle in all participants (r = −0.50). No significant relationships were found between core stability and performance variables. A significant difference was found in the pro-agility shuttle (p = 0.001) and the CMJ (p = 0.001) but not in core stability or dynamic stability. Agility, power production, and dynamic stability were not related to core stability in neither male or female lacrosse players. There were no significant differences in core stability and dynamic stability between males and females. A significant difference was found in dynamic stability in the SEBT right leg and left leg composite scores between sexes. From these results, it is suggested that core stability may not directly influence the performance variables in collegiate male and female lacrosse players.

Published
2019

46. Synthesis and Biological Evaluation of New Eugenol-Derived 1,2,3- Triazoles as Antimyco bacterial Agents

Author

Santos, Thiago dos, Coelho, Camila M., Elias, Thiago C., Siqueira, Fallon S., Nora, Eloísa S. S. D., Campos, Marli M. A. de, Souza, Gabriel A. P. de, Coelho, Luiz F. L., and Carvalho, Diogo T.

Subjects
1,2,3-triazoles, eugenol, rapid growing mycobacteria, mycobacterium
Abstract

Eugenol has diverse biological properties including antimycobacterial activity, and the triazole ring is an important heterocycle in antimycobacterial compounds. Therefore, this research aimed to synthesize novel eugenol-derived 1,2,3-triazole as antimycobacterial agents with interesting cytotoxic profile and pharmacological assets. Sixteen compounds were obtained and characterized by nuclear magnetic resonance (NMR), infrared (IR), and high-resolution mass spectrometry (HRMS). Among them, the best growth inhibition properties from a microdilution assay were observed for three derivatives: a benzylic ether (minimum inhibitory concentration (MIC) = 48.89 µM) against Mycobacterium abscessus (ATCC 19977), an O-galactosyde (MIC = 31.76 µM) against Mycobacterium massiliense (ATCC 48898) and a sulfonate (MIC = 88.64 µM) against Mycobacterium fortuitum (ATCC 6841). They can form biofilms, and the infection progression is challenging to control due to multi-drug resistance profiles against diverse antibiotics. In conclusion, the above-mentioned compounds represent starting points in the search of bioactive molecules against mycobacteria with low cytotoxicity and better pharmacological profiles.

Published
2019

47. Task-irrelevant financial losses inhibit the removal of information from working memory

Author

Fallon, S, Dolfen, N, Parolo, F, Zokaei, N, and Husain, M

Subjects
Adult, Male, lcsh:R, lcsh:Medicine, Article, Young Adult, Memory, Short-Term, Reward, Humans, lcsh:Q, Attention, Female, Cues, lcsh:Science
Abstract

The receipt of financial rewards or penalties - though task-irrelevant - may exert an obligatory effect on manipulating items in working memory (WM) by constraining a forthcoming shift in attention or reinforcing attentional shifts that have previously occurred. Here, we adjudicate between these two hypotheses by varying - after encoding- the order in which task-irrelevant financial outcomes and cues indicating which items need to be retained in memory are presented (so called retrocues). We employed a "what-is-where" design that allowed for the fractionation of WM recall into separate components: identification, precision and binding (between location and identity). Principally, valence-dependent effects were observed only for precision and binding, but only when outcomes were presented before, rather than after, the retrocue. Specifically, task-irrelevant financial losses presented before the retrocue caused a systematic breakdown in binding (misbinding), whereby the features of cued and non-cued memoranda became confused, i.e., the features that made up relevant memoranda were displaced by those of non-cued (irrelevant) items. A control experiment, in which outcomes but no cues were presented, failed to produce the same effects, indicating that the inclusion of retrocues were necessary for generating this effect. These results show that the receipt of financial penalties - even when uncoupled to performance - can prevent irrelevant information from being effectively pruned from WM. These results illustrate the importance of reward-related processing to controlling the contents of WM. ispartof: SCIENTIFIC REPORTS vol:9 issue:1 ispartof: location:England status: published

Published
2019

48. Neural mechanisms of attending to items in working memory

Author

Manohar, S, Zokaei, N, Fallon, S, Vogels, T, and Husain, M

Subjects
Neurons, Neuronal Plasticity, Models, Neurological, neural networks, working memory, Article, attention, attractor network, Hebbian plasticity, Memory, Short-Term, Synapses, Animals, Humans, Attention, Neural Networks, Computer
Abstract

Working memory, the ability to keep recently accessed information available for immediate manipulation, has been proposed to rely on two mechanisms that appear difficult to reconcile: self-sustained neural firing, or the opposite—activity-silent synaptic traces. Here we review and contrast models of these two mechanisms, and then show that both phenomena can co-exist within a unified system in which neurons hold information in both activity and synapses. Rapid plasticity in flexibly-coding neurons allows features to be bound together into objects, with an important emergent property being the focus of attention. One memory item is held by persistent activity in an attended or “focused” state, and is thus remembered better than other items. Other, previously attended items can remain in memory but in the background, encoded in activity-silent synaptic traces. This dual functional architecture provides a unified common mechanism accounting for a diversity of perplexing attention and memory effects that have been hitherto difficult to explain in a single theoretical framework.

Published
2019

50. Causes and consequences of limitations in visual working memory

Author

Fallon, S, Zokaei, N, and Husain, M

Subjects
Memory, Short-Term, binding, hippocampus, basal ganglia, Models, Neurological, Visual Perception, Humans, Original Article, precision, Attention, Original Articles, working memory, Corpus Striatum
Abstract

Recent methodological and conceptual advances have led to a fundamental reappraisal of the nature of visual working memory (WM). A large corpus of evidence now suggests that there might not be a hard limit on the number of items that can be stored. Instead, WM may be better captured by a highly limited––but flexible––resource model. More resource can be allocated to prioritized items but, crucially, at a cost of reduced recall precision for other stored items. Expectations may modulate resource distribution, for example, through neural oscillations in the alpha band increasing inhibition of irrelevant cortical regions. Our understanding of the neural architecture of WM is also undergoing radical revision. Whereas the prefrontal cortex has previously dominated research endeavors, other cortical regions, such as early visual areas, are now considered to make an essential contribution, for example holding one or more items in a privileged state or “focus of attention” within WM. By contrast, the striatum is increasingly viewed as crucial in determining why and how items are gated into memory, while the hippocampus, it has controversially been argued, might be critical in the formation of temporally resilient conjunctions across features of stored items in WM.

Published
2016

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