Eye movements used for the objective assessment of contrast sensitivity

Assessment of contrast sensitivity (CS) from eye movements has already been proposed as a possible method to gain objective information about this visual function. The currently submitted dissertation holding the title Eye movements used for the objective assessment of contrast sensitivity improves the currently proposed approaches of the eye-movement-based CS tests and proposes novel ones. The first project of this dissertation extends the applicability of microsaccadic rate signatures, already proposed as the tool for objective CS testing, into the clinical practice by stimulation of microsaccades under monocular conditions, while analyzing the eye movements as binocular events. In this approach an infra-red filter for covering the left eye of the tested subjects and an infrared eye-tracker were used, resulting in the stimulation of just one eye of the participant, however allowing the eye movement detection in both eyes. Because the microsaccadic events were found to be rare in some participants, the second project utilized optokinetic nystagmus in CS testing. In this project, the optokinetic nystagmus was detected in real-time when running the experiment, using a newly-developed life detection method, and along with a one-dimensional adaptive psychometric procedure (QUEST+) for the contrast level management enabled a fully automated CS examination. Furthermore, the examination was conducted for a range of spatial frequencies of a grating as well as a range of defocus conditions, replicating the well-known effects on CS from the clinical trials. The third project aimed to extend the eye-movement-based testing also to the peripheral visual field, and thus replicate the CS perimetry testing procedure in an objective way. In this project CS was tested using reflexive (reactive) saccades, occurring towards a newly presented target, which was located in one of the four cardinal directions in the patient’s visual field. Here the four independent QUEST+ psychometric procedures sought for the contrast threshold in the four directions individually, for each of the three tested eccentricity levels. Moreover, the measurements were conducted for the eye-movement-based and key-board-based measurements to run a rounded validation of this novel procedure, showing its feasibility for future clinical application. In conclusion, this thesis extends an improves the portfolio of eye movements used in CS testing, shows novel approaches to improve the time efficiency, and replicates the well-known effects from the clinical trials

First Direct Detection Limits on sub-GeV Dark Matter from XENON10

The first direct detection limits on dark matter in the MeV to GeV mass range are presented, using XENON10 data. Such light dark matter can scatter with electrons, causing ionization of atoms in a detector target material and leading to single- or few-electron events. We use 15 kg-days of data acquired in 2006 to set limits on the dark-matter-electron scattering cross section. The strongest bound is obtained at 100 MeV where sigma_e < 3 x 10^{-38} cm^2 at 90% CL, while dark matter masses between 20 MeV and 1 GeV are bounded by sigma_e < 10^{-37} cm^2 at 90% CL. This analysis provides a first proof-of-principle that direct detection experiments can be sensitive to dark matter candidates with masses well below the GeV scale.Comment: Submitted to PR

Atomic-scale coexistence of short-range magnetic order and superconductivity in Fe1+y_{1+y}Se0.1_{0.1}Te0.9_{0.9}

The ground state of the parent compounds of many high temperature superconductors is an antiferromagnetically (AFM) ordered phase, where superconductivity emerges when the AFM phase transition is suppressed by doping or application of pressure. This behaviour implies a close relation between the two orders. Understanding the interplay between them promises a better understanding of how the superconducting condensate forms from the AFM ordered background. Here we explore this relation in real space at the atomic scale using low temperature spin-polarized scanning tunneling microscopy (SP-STM) and spectroscopy. We investigate the transition from antiferromagnetically ordered $\mathrm{Fe}_{1+y}\mathrm{Te}$ via the spin glass phase in $\mathrm{Fe}_{1+y}\mathrm{Se}_{0.1}\mathrm{Te}_{0.9}$ to superconducting $\mathrm{Fe}_{1+y}\mathrm{Se}_{0.15}\mathrm{Te}_{0.85}$. In $\mathrm{Fe}_{1+y}\mathrm{Se}_{0.1}\mathrm{Te}_{0.9}$ we observe an atomic-scale coexistence of superconductivity and short-ranged bicollinear antiferromagnetic order.Comment: 7 pages, 6 figure

Atomic-scale coexistence of short-range magnetic order and superconductivity in Fe1+ySe0.1Te0.9

Funding: UK EPSRC (EP/I031014/1) (HZ, J-PR, and PW)The ground state of the parent compounds of many high-temperature superconductors is an antiferromagnetically ordered phase, where superconductivity emerges when the antiferromagnetic phase transition is suppressed by doping or application of pressure. This behavior implies a close relation between the two orders. Examining the interplay between them promises a better understanding of how the superconducting condensate forms from the antiferromagnetically ordered background. Here we explore this relation in real space at the atomic scale using low-temperature spin-polarized scanning tunneling microscopy and spectroscopy. We investigate the transition from antiferromagnetically ordered Fe1+yTe via the spin-glass phase in Fe1+ySe0.1Te0.9 to superconducting Fe1+ySe0.15Te0.85. In Fe1+ySe0.1Te0.9 we observe an atomic-scale coexistence of superconductivity and short-ranged bicollinear antiferromagnetic order. However, a direct correlation between the two orders is not observed, supporting the scenario of s± superconducting symmetry in this material. Our work demonstrates a direct probe of the relation between the two orders, which is indispensable for our understanding of high-temperature superconductivity.Publisher PDFPeer reviewe

The Vehicle, Spring 1993

Table of Contents The Shape of Things to Come.Peter F. Essigpage 6 SaxophoneWalt Howardpage 6 Gravity BedSue Songerpage 7 UntitledJennifer Gutowskipage 8 uncertaintyWalt Howardpage 9 Ruth Ann, et. al.Susan Eisenhourpage 9 Failed IndustryScott Langenpage 10 UntitledKaren Wisspage 10 wanted:Walt Howardpage 10 Dida; 1978Diana Matijaspage 11 UntitledJennifer Gutowskipage 12 The Lesson in NovemberSue Songerpage 13 Coal MinerJames P. Tangpage 16 Christmas CrueltySue Songerpage 17 Astral ProjectionSusan Eisenhourpage 18 UntitledBen Hausmannpage 19 Into Zagreb\u27s Evening*Diana Matjaspage 20 UntitledJennifer Gutowskipage 22 The AnniversaryJennifer Moropage 23 NudeDan Trutterpage 24 death for saleWalt Howardpage 24 JudgedKevin St. Angelpage 25 Nature\u27s RefugeeScott Langenpage 25 Arrowhead Hunting at TippecanoeJennifer Moropage 26 UntitledKimberly Foxpage 27 TAINTED LOVESarah C. Patiencepage 28 cemeteryWalt Howardpage 28 Cow GameSusan Eisenhourpage 29 UntitledJennifer Gutowskipage 31 ReflectionsPeter F. Essigpage 32 Destination U.S.A.Dan Trutterpage 33 UntitledMario Letopage 33 Authors\u27 Pagepage 34https://thekeep.eiu.edu/vehicle/1061/thumbnail.jp

The Vehicle, Spring 1993

Table of Contents The Shape of Things to Come.Peter F. Essigpage 6 SaxophoneWalt Howardpage 6 Gravity BedSue Songerpage 7 UntitledJennifer Gutowskipage 8 uncertaintyWalt Howardpage 9 Ruth Ann, et. al.Susan Eisenhourpage 9 Failed IndustryScott Langenpage 10 UntitledKaren Wisspage 10 wanted:Walt Howardpage 10 Dida; 1978Diana Matijaspage 11 UntitledJennifer Gutowskipage 12 The Lesson in NovemberSue Songerpage 13 Coal MinerJames P. Tangpage 16 Christmas CrueltySue Songerpage 17 Astral ProjectionSusan Eisenhourpage 18 UntitledBen Hausmannpage 19 Into Zagreb\u27s Evening*Diana Matjaspage 20 UntitledJennifer Gutowskipage 22 The AnniversaryJennifer Moropage 23 NudeDan Trutterpage 24 death for saleWalt Howardpage 24 JudgedKevin St. Angelpage 25 Nature\u27s RefugeeScott Langenpage 25 Arrowhead Hunting at TippecanoeJennifer Moropage 26 UntitledKimberly Foxpage 27 TAINTED LOVESarah C. Patiencepage 28 cemeteryWalt Howardpage 28 Cow GameSusan Eisenhourpage 29 UntitledJennifer Gutowskipage 31 ReflectionsPeter F. Essigpage 32 Destination U.S.A.Dan Trutterpage 33 UntitledMario Letopage 33 Authors\u27 Pagepage 34https://thekeep.eiu.edu/vehicle/1061/thumbnail.jp

The Vehicle, Fall 1992

Table of Contents DeconstructivismPeter F. Essigpage 5 Homecoming Pep RallyPeter F. Essigpage 6 McAfee GymnasiumWalt Howardpage 7 Morton ParkAnn Moutraypage 9 Why The Willows WeepPeter F. Essigpage 10 UntitledStephen P. Carmodypage 10 A Stranger\u27s MorningBen Hausmannpage 11 deMONSTERative pronounsJoAnna Wolaverpage 12 2.5%Jill S. Pilonpage 13 The BottleStacey Kruegerpage 14 Suppression Jean K. Graypage 15 ProgressStacey Kruegerpage 16 Daily LessonsJennifer Moropage 17 Sunset TheaterMichelle R. Hokepage 20 Eagle GT\u27sJarrod T. Shieldspage 21 New HouseRandy Lisspage 22 UntitledStephen P. Carmodypage 23 Renting Classics on a Saturday NightNancy Jamespage 24 UntitledJacqueline Hallpage 25 Alone While He SleepsSandy Beauchamppage 26 Sand and SeaThomas Schnarrepage 27 loveMichelle R. Hokepage 28 Backward Ass Junkie FunkSandy Beauchamppage 28 These Things You KeepTom McGrathpage 29 Springhill CrestRobert M. Reutherpage 30 The Pass OverLarry Irvinpage 31 The Stolen ChildTom McGrathpage 32 Before the Recycling KickWalt Howardpage 37 Authors\u27 Pagepage 38https://thekeep.eiu.edu/vehicle/1058/thumbnail.jp

Early postoperative MRI overestimates residual tumour after resection of gliomas with no or minimal enhancement

Standards for residual tumour measurement after resection of gliomas with no or minimal enhancement have not yet been established. In this study residual volumes on early and late postoperative T2-/FLAIR-weighted MRI are compared. A retrospective cohort included 58 consecutive glioma patients with no or minimal preoperative gadolinium enhancement. Inclusion criteria were first-time resection between 2007 and 2009 with a T2-/FLAIR-based target volume and availability of preoperative, early (<48 h) and late (1-7 months) postoperative MRI. The volumes of non-enhancing T2/FLAIR tissue and diffusion restriction areas were measured. Residual tumour volumes were 22% smaller on late postoperative compared with early postoperative T2-weighted MRI and 49% smaller for FLAIR-weighted imaging. Postoperative restricted diffusion volume correlated with the difference between early and late postoperative FLAIR volumes and with the difference between T2 and FLAIR volumes on early postoperative MRI. We observed a systematic and substantial overestimation of residual non-enhancing volume on MRI within 48 h of resection compared with months postoperatively, in particular for FLAIR imaging. Resection-induced ischaemia contributes to this overestimation, as may other operative effects. This indicates that early postoperative MRI is less reliable to determine the extent of non-enhancing residual glioma and restricted diffusion volumes are imperativ

The Vehicle, Fall 1993

Table of Contents 7/10ths SynthesisPeter F. Essigpage 5 Aug 1992 (My Small Catechism)Jon Montgomerypage 6 Chaos Is-J. Dylan McNeillpage 7 UntouchedTraci Williamspage 8 The JustificationJohn C. Carminepage 8 LincolnJon Montgomerypage 9 Untitled (Photo)Nicole Niemanpage 10 Park PoemJohn Brillhartpage 11 SmokeJulia Ann Canhampage 12 Warming the BenchAnn Moutraypage 12 Cereal KillerJay Harnackpage 13 The Dutiful SonsTom McGrathpage 14 UntitledCatherine DeGraafpage 17 7-up bottleWalt Howardpage 17 BreedDan Trutterpage 18 An Argument Against LoveTony Martinezpage 19 UntitledT. Scott Laniganpage 19 Glassblowers BallStephanie Franzenpage 20 Portrait of a Young GirlJohn C. Carminepage 20 Untitled (artwork)Dan Trutterpage 21 Death of a FriendLizabeth Kulkapage 22 Submission BluesMartin Paul Brittpage 23 To the Fourteen Year Old SuicideScott Langenpage 23 The Flabby PilgrimTom McGrathpage 24 The Fall of ImmortalityBrian Wheelerpage 25 Merging with AirThom Schnarrepage 26 UntitledCatherine DeGraafpage 27 Tree FishSandra Beauchamppage 28 Country SlumberJ. Dylan McNeillpage 29 Untitled (artwork)Dan Trutterpage 33 Authors\u27 Pagepage 34https://thekeep.eiu.edu/vehicle/1060/thumbnail.jp