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Does correction for guessing reduce students' performance on multiple-choice examinations? Yes? No? Sometimes?
Multiple-choice (MC) examinations are becoming increasingly popular in higher education because they can be used effectively to assess breadth of knowledge in large cohorts of students. This present research investigated Psychology students' performance on, and experiences of, MC examinations with and without correction for guessing. In Study 1, data were collected from two cohorts of students across three Psychology MC examinations. The results revealed that students scored higher, and left fewer questions unanswered, when there was no correction for guessing. Furthermore, when the correction for guessing was removed from the theory MC examination, students who were told there was no correction for guessing did better than those told there was a correction. In addition, there was limited evidence of gender differences, with female students performing significantly better on one MC examination than males. In Study 2, a further set of first-year Psychology students reported their experiences of correction for guessing on open-book and closed-book MC examinations. Students reported feeling less anxious and more confident on the open-book MC examination. The findings of both of these studies have implications for instructors deciding whether or not correction for guessing is appropriate, and for the advice to be given to students preparing for MC examinations
Program for transfer research and impact studies
Research activities conducted under the program for Transfer Research and impact studies are reviewed. Programs include: Tech Brief - Technical Support Package (TSP) Program; transfer documentation; and technology transfer profiles. An analysis of user behavior patterns is made by studying questionnaires filled out by users of the Tech Brief - TSP program. The process of technology transfer is discussed in terms of improving its effectiveness
Physical lumping methods for developing linear reduced models for high speed propulsion systems
In gasdynamic systems, information travels in one direction for supersonic flow and in both directions for subsonic flow. A shock occurs at the transition from supersonic to subsonic flow. Thus, to simulate these systems, any simulation method implemented for the quasi-one-dimensional Euler equations must have the ability to capture the shock. In this paper, a technique combining both backward and central differencing is presented. The equations are subsequently linearized about an operating point and formulated into a linear state space model. After proper implementation of the boundary conditions, the model order is reduced from 123 to less than 10 using the Schur method of balancing. Simulations comparing frequency and step response of the reduced order model and the original system models are presented
Feasibility analysis of reciprocating magnetic heat pumps
The conceptual design selected for detailed system analysis and optimization is the reciprocating gadolinium core in a regenerative fluid column within the bore of a superconducting magnet. The thermodynamic properties of gadolinium are given. A computerized literature search for relevant papers was conducted and is being analyzed. Contact was made with suppliers of superconducting magnets and accessories, magnetic materials, and various types of hardware. A description of the model for the thermal analysis of the core and regenerator fluids is included
Program for transfer research and impact studies
Research activities conducted under the Program for Transfer Research and Impact Studies (TRIS) during 1972 included: (1) preparation of 10,196 TSP requests for TRIS application analysis; (2) interviews with over 500 individuals concerning the technical, economic, and social impacts of NASA-generated technology; (3) preparation of 38 new technology transfer example files and 101 new transfer cases; and (4) maintenance of a technology transfer library containing more than 2,900 titles. Six different modes of technology utilization are used to illustrate the pervasiveness of the transfer and diffusion of aerospace innovations. These modes also provide a basis for distinguishing the unique characteristics of the NASA Technology Utilization Program. An examination is reported of the ways in which NASA-generated technology is contributing to beneficial social change in five major areas of human concern: health, environment, safety, transportation, and communication
A cell-permeable biscyclooctyne as a novel probe for the identification of protein sulfenic acids
Reactive oxygen species act as important second messengers in cell signaling and homeostasis through the oxidation of protein thiols. However, the dynamic nature of protein oxidation and the lack of sensitivity of existing molecular probes have hindered our understanding of such reactions; therefore, new tools are required to address these challenges. We designed a bifunctional variant of the strained bicyclo[6.1.0]nonyne (BCN-E-BCN) that enables the tagging of intracellular protein sulfenic acids for biorthogonal copper-free click chemistry. In validation studies, BCN-E-BCN binds the sulfenylated form of the actin-severing protein cofilin, while mutation of the cognate cysteine residues abrogates its binding. BCN-E-BCN is cell permeable and reacts rapidly with cysteine sulfenic acids in cultured cells. Using different azide-tagged conjugates, we demonstrate that BCN-E-BCN can be used in various applications for the detection of sulfenylated proteins. Remarkably, cycloaddition of an azide-tagged fluorophore to BCN-E-BCN labelled proteins produced in vivo can be visualized by fluorescence microscopy to reveal their subcellular localization. These findings demonstrate a novel and multifaceted approach to the detection and trapping of sulfenic acids
On the hydrographic mechanism of the so-called brown zones associated with tidal glaciers
The presence of zones of muddy, ice-free water at the sea faces of tidal glaciers has been recorded from Alaska (Gilbert, 1910), and from Spitzbergen (Stott, 1936). In view of their great significance in local ecology an understanding of the causes of these so-called Brown Zones seemed desirable and the problem of their establishment was first attacked hydrographically by the Oxford University Expedition to Spitzbergen, in 1933...
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