On a clique covering problem of orlin

AbstractLet T2n be the complement of a perfect matching in the complete graph on 2n vertices, and cc(T2n) be the minimum number of complete subgraphs necessary to cover all the edges of T2n Orlin posed the problem of determining the asymptotic behaviour of cc(T2n). We show that cc(T2n)=min{k:n⩽(k−1⌈k2⌉)} for all n>1, (which implies that limn→∞cc(T 2n)/log2n=1). This is done by applying a Sperner-type theorem on set families due to Bollobás and Schönheim

Visual Methods: Using Photographs to Capture Customers’ Experience with Design

Traditional guest feedback methods such as surveys or mystery shopping are not ideal for collecting information about customers\u27 reactions to a hotel\u27s physical design. Because design is a visual medium, survey questions may not capture the whole of a guest\u27s reaction to the design. By the same token, the reaction of mystery shoppers to design is not necessarily representative of all guests. Instead, a photography-based approach allows guests to show managers and researchers what they consider to be the hotel\u27s design highlights and failures. A pilot study indicated that guests took notice of design elements that signified that the hotel was being considerate of their needs, as well as providing a functional, high-quality environment

The petrography and petrology of a portion of the northern Cedar Mountains, Mineral County, Nevada

Online access for this thesis was created in part with support from the Institute of Museum and Library Services (IMLS) administered by the Nevada State Library, Archives and Public Records through the Library Services and Technology Act (LSTA). To obtain a high quality image or document please contact the DeLaMare Library at https://unr.libanswers.com/ or call: 775-784-6945.A combined field and petrographic study describes the spatial mineralogical and textural characteristics of the Cedar Pass pluton and related volcanic rocks. Correlation between mantled feldspars, basic inclusions and geochemistry is made in order to determine the petrologic development of these igneous rocks. The study area is 30 kilometers northeast of Mina, Mineral County, Nevada in the northern Cedar Mountains. Well exposed sub-volcanic rocks have intruded into late Triassic marine sediments. Three periods of structural deformation have been imprinted on these rocks. These plutonic rocks are related to a period of extrusive eruptions which started about 28 million years ago and culminated about 10 million years ago. A minor phase of the pluton has been dated by K-Ar at 24.2 million years. Myrmekite, mantled feldspars and plagioclase morphology have been used to determine the igneous history during Oligocene-Miocene time

Holmes Tremor due to Artery of Percheron Infarct: Clinical Case and Treatment Using Deep Brain Stimulation of the Vim and ZI Targets

Background: Holmes tremor (HT) arises from disruption of the cerebellothalamocortical pathways. A lesion can interrupt the projection at any point, resulting in this tremor. We describe a case of HT due to the rare artery of Percheron infarct and its successful treatment using deep brain stimulation. Case report: A 62-year-old woman with a right medial cerebral peduncle and bilateral thalamic stroke developed HT. Ventral intermediate nucleus (Vim) zona incerta (ZI) deep brain stimulation (DBS) surgery was performed, with improvement in her tremor. Discussion: Our case supports the theory that the more caudal ZI target in combination with Vim is beneficial in treating poorly DBS-responsive tremors such as HT

Digitized Spiral Drawing: A Possible Biomarker for Early Parkinson’s Disease

Introduction Pre-clinical markers of Parkinson’s Disease (PD) are needed, and to be relevant in pre-clinical disease, they should be quantifiably abnormal in early disease as well. Handwriting is impaired early in PD and can be evaluated using computerized analysis of drawn spirals, capturing kinematic, dynamic, and spatial abnormalities and calculating indices that quantify motor performance and disability. Digitized spiral drawing correlates with motor scores and may be more sensitive in detecting early changes than subjective ratings. However, whether changes in spiral drawing are abnormal compared with controls and whether changes are detected in early PD are unknown. Methods 138 PD subjects (50 with early PD) and 150 controls drew spirals on a digitizing tablet, generating x, y, z (pressure) data-coordinates and time. Derived indices corresponded to overall spiral execution (severity), shape and kinematic irregularity (second order smoothness, first order zero-crossing), tightness, mean speed and variability of spiral width. Linear mixed effect adjusted models comparing these indices and cross-validation were performed. Receiver operating characteristic analysis was applied to examine discriminative validity of combined indices. Results All indices were significantly different between PD cases and controls, except for zero-crossing. A model using all indices had high discriminative validity (sensitivity = 0.86, specificity = 0.81). Discriminative validity was maintained in patients with early PD. Conclusion Spiral analysis accurately discriminates subjects with PD and early PD from controls supporting a role as a promising quantitative biomarker. Further assessment is needed to determine whether spiral changes are PD specific compared with other disorders and if present in pre-clinical PD

A Framework for Evaluating the Customer Wait Experience

Purpose – The purpose of this paper is to propose and test a model which defines the psychological processes that mediate the relationship between perceived wait duration (PWD) and satisfaction. This model will provide a framework for evaluating the impact of situational and environmental variables in the servicescape on customer reaction to the wait experience. Design/methodology/approach – The approach included one field study and two laboratory experiments in which subjects participated in a service with a pre-process wait and evaluated their experience on a survey. Findings – Perceived wasted time, perceived control, perceived boredom, and perceived neglect mediated the relationship between PWD and wait experience evaluation. When tested using filled versus unfilled wait time as the situational variable, the model showed that having something to do during the wait decreased perceived boredom, resulting in a more positive wait experience. Research limitations/implications – The services used in this paper were functional (as opposed to hedonistic) in nature and wait durations were a maximum of ten minutes. Originality/value – The framework established in this paper can be used to evaluate customer reaction to the elements of the waiting environment design, which will help managers design waiting environments that maximize customer satisfaction, and help researchers to understand changes in the relationship between PWD and satisfaction under different environmental conditions

Past electron-positron g-2 experiments yielded sharpest bound on CPT violation for point particles

In our past experiments on a single electron and positron we measured the cyclotron and spin-cyclotron difference frequencies omega_c and omega_a and the ratios a = omega_a/ omega_c at omega_c = 141 Ghz for e^- and e^+ and later, only for e^-, also at 164 Ghz. Here, we do extract from these data, as had not done before, a new and very different figure of merit for violation of CPT symmetry, one similar to the widely recognized impressive limit |m_Kaon - m_Antikaon|/m_Kaon < 10^-18 for the K-mesons composed of two quarks. That expression may be seen as comparing experimental relativistic masses of particle states before and after the C, P, T operations had transformed particle into antiparticle. Such a similar figure of merit for a non-composite and quite different lepton, found by us from our Delta a = a^- - a^+ data, was even smaller, h_bar |omega_a^- - omega_a^+|/2m_0 c^2 = |Delta a| h_bar omega_c/2m_0 c^2) < 3(12) 10^-22.Comment: Improved content, Editorially approved for publication in PRL, LATEX file, 5 pages, no figures, 16

Sarcoidosis presenting as Wallenberg syndrome and panuveitis

© 2018 The Authors Sarcoidosis is a multi-system disease with neurological involvement being one of the more rare manifestations. We report a case of a patient who presented with the lateral medullary syndrome and panuveitis as her initial manifestation of sarcoidosis. The patient\u27s course was further complicated by renal involvement. Lacrimal gland and renal biopsies showed noncaseating granulomas without evidence of infection, establishing the diagnosis. Intracranial vertebral artery involvement was confirmed by brain imaging. Bilateral hilar lymphadenopathy with upper lobe predominant nodules on chest imaging was consistent with asymptomatic pulmonary involvement. Systemic steroid therapy is indicated for treatment of ocular sarcoidosis, with standard stroke management indicated for the treatment of lateral medullary syndrome