Stability Implications of Bendixson’s Criterion

This note presents a proof that the omega limit set of a solution to a planar system satisfying the Bendixson criterion is either empty or is a single equilibrium. The proof involves elementary techniques which should be accessible to senior undergraduates and graduate students

An Sveir Model for Assessing Potential Impact of an Imperfect Anti-SARS Vaccine

The control of severe acute respiratory syndrome (SARS), a fatal contagious viral disease that spread to over 32 countries in 2003, was based on quarantine of latently infected individuals and isolation of individuals with clinical symptoms of SARS. Owing to the recent ongoing clinical trials of some candidate anti-SARS vaccines, this study aims to assess, via mathematical modelling, the potential impact of a SARS vaccine, assumed to be imperfect, in curtailing future outbreaks. A relatively simple deterministic model is designed for this purpose. It is shown, using Lyapunov function theory and the theory of compound matrices, that the dynamics of the model are determined by a certain threshold quantity known as the control reproduction number (Rv). If Rv ≤ 1, the disease will be eliminated from the community; whereas an epidemic occurs if Rv \u3e 1. This study further shows that an imperfect SARS vaccine with infection-blocking efficacy is always beneficial in reducing disease spread within the community, although its overall impact increases with increasing efficacy and coverage. In particular, it is shown that the fraction of individuals vaccinated at steady-state and vaccine efficacy play equal roles in reducing disease burden, and the vaccine must have efficacy of at least 75% to lead to effective control of SARS (assuming R0 = 4). Numerical simulations are used to explore the severity of outbreaks when Rv \u3e 1

Constructing a math applications, curriculum-based assessment: an analysis of the relationship between apllications [sic] problems, computation problems and criterion-referenced assessments

Curriculum-based measurement (CBM) is a well established tool for formative assessment. CBM has also been used for prediction of state test scores. However, validity coefficients between math-CBM and state tests have been moderate at best (Skiba, Magnusson, Martson, and Erickson, 1986; Martson, 1989; Putnam, 1989). The purpose of the present investigation was to develop and evaluate a set of math assessments designed to measure the type of application and problem-solving objectives required on state tests. The application type assessments constructed for this study combined characteristics of CBM, accuracy-based curriculum-based assessment (CBA) and criterion-referenced assessment (CRA). Theses assessments were derived from state standards and matched to local district curriculum. The methodology involved obtaining validity coefficients for (a) traditional CBM assessments versus (b) newly developed assessments which incorporated applications/problem-solving with regard to state tests which served as a standard against which (a) and (b) above could be evaluated. The assessments examined included (a) one single skill computation assessment, (b) one multiple skill computation assessment, (c) one maze reading assessment, (d) a newly constructed applications assessment, (e) Woodcock-Johnson III math subtests, (f) Louisiana Education Program for the 21st Century (LEAP), and (g) the Iowa Test of Basic Skills (ITBS). Additionally, the various assessments were investigated relative to teacher-based indicators including (a) students\u27 final grades, (b) teacher report of year end performance, and (c) teacher preference of math assessments. Participants included 172 first to fifth grade regular education students who were administered the CBM/CBA/CRA assessments one month following the state tests. State testing included use of the LEAP in fourth grade and the ITBS in second, third and fifth grades. Results indicated that the newly developed application assessment exhibited a stronger relationship with the criterion assessments, with students\u27 final grades, and teacher report of year-end performance. In addition, the application type assessments were preferred over the computation assessments by all teachers. Results and limitations are discussed with regard to the construction and use of an application-oriented CBM/CBA/CRA for users needing assessment which might combine the power of formative evaluation with the ability to accurately predict performance on state tests

Basic principles and recent observations of rotationally sampled wind

The concept of rotationally sampled wind speed is described. The unusual wind characteristics that result from rotationally sampling the wind are shown first for early measurements made using an 8-point ring of anemometers on a vertical plane array of meteorological towers. Quantitative characterization of the rotationally sampled wind is made in terms of the power spectral density function of the wind speed. Verification of the importance of the new concept is demonstrated with spectral analyses of the response of the MOD-OA blade flapwise root bending moment and the corresponding rotational analysis of the wind measured immediately upwind of the MOD-OA using a 12-point ring of anemometers on a 7-tower vertical plane array. The Pacific Northwest Laboratory (PNL) theory of the rotationally sampled wind speed power spectral density function is tested successfully against the wind spectrum measured at the MOD-OA vertical plane array. A single-tower empirical model of the rotationally sampled wind speed is also successfully tested against the measurements from the full vertical plane array. Rotational measurements of the wind velocity with hotfilm anemometers attached to rotating blades are shown to be accurate and practical for research on winds at the blades of wind turbines. Some measurements at the rotor blade of a MOD-2 turbine using the hotfilm technique in a pilot research program are shown. They are compared and contrasted to the expectations based upon application of the PNL theory of rotationally sampled wind to the MOD-2 size and rotation rate but without teeter, blade bending, or rotor induction accounted for. Finally, the importance of temperature layering and of wind modifications due to flow over complex terrain is demonstrated by the use of hotfilm anemometer data, and meteorological tower and acoustic doppler sounder data from the MOD-2 site at Goodnoe Hills, Washington

Biological Weapons Convention's (BWC)'s 2014-2015 Final Report

Project on Advanced Systems and Concepts for Countering Weapons of Mass Destruction (PASCC)Prepared under the auspices of the IAP Biosecurity Working GroupAssistance Grant/Agreement No. GRANT N00244-14-1-003

Obstacles to torture rehabilitation at Guantánamo Bay

This article sets out the legal duty of the United States of America to provide victims of torture and cruel, inhumane and degrading treatment (CIDT) the right to full rehabilitation under international law, including those still detained at the facility at Guantánamo Bay. After an examination of some of the torture methods used on these detainees, while they were in the custody of the CIA and arguably afterwards, it goes on to indicate the current obstacles to rehabilitation, including on-going incarceration, lack of impunity, classification of medical documents and limited access to non-military staff. Limited options for possible psychological assistance towards the right to rehabilitation are considered

The Annenberg Challenge: Lessons and Reflections on Public School Reform

Presents findings and recommendations from an initiative that established eighteen projects in public schools across the U.S. to improve education in inner city schools, provide assistance to isolated rural schools, and expand access to arts education

The Lancaster Sensorimotor Norms : Multidimensional measures of Perceptual and Action Strength for 40,000 English words

Sensorimotor information plays a fundamental role in cognition. However, the existing materials that measure the sensorimotor basis of word meanings and concepts have been restricted in terms of their sample size and breadth of sensorimotor experience. Here we present norms of sensorimotor strength for 39,707 concepts across six perceptual modalities (touch, hearing, smell, taste, vision, and interoception) and five action effectors (mouth/throat, hand/arm, foot/leg, head excluding mouth/throat, and torso), gathered from a total of 3,500 individual participants using Amazon’s Mechanical Turk platform. The Lancaster Sensorimotor Norms are unique and innovative in a number of respects: They represent the largest-ever set of semantic norms for English, at 40,000 words × 11 dimensions (plus several informative cross-dimensional variables), they extend perceptual strength norming to the new modality of interoception, and they include the first norming of action strength across separate bodily effectors. In the first study, we describe the data collection procedures, provide summary descriptives of the dataset, and interpret the relations observed between sensorimotor dimensions. We then report two further studies, in which we (1) extracted an optimal single-variable composite of the 11-dimension sensorimotor profile (Minkowski 3 strength) and (2) demonstrated the utility of both perceptual and action strength in facilitating lexical decision times and accuracy in two separate datasets. These norms provide a valuable resource to researchers in diverse areas, including psycholinguistics, grounded cognition, cognitive semantics, knowledge representation, machine learning, and big-data approaches to the analysis of language and conceptual representations. The data are accessible via the Open Science Framework (http://osf.io/7emr6/) and an interactive web application (https://www.lancaster.ac.uk/psychology/lsnorms/)