Showing papers by "David W. Johnson published in 1993"

Cooperation in the Classroom

Abstract: Originally published in Contemporary Psychology: APA Review of Books, 1991, Vol 36(12), 1106–1107. Reviews the book, Cooperative Learning: Critical Thinking and Collaboration Across the Curriculum by Dennis M. Adams and Mary E. Hamm (see record 1990-97476-000). Adams and Hamm have written one of the latest books encouraging teachers to begin using cooperative learning. Adams and Hamm have put together an interesting and useful book for teachers. Broad generations, with quotes from both popular and scholarly sources interspersed, are used to highlight the conclusion that cooperative learning is an important instructional procedure. The authors build a case that cooperative learning should be used because of its relevance to work, citizenship, and critical thinking. They present a rationale for using cooperative learning in language arts, science and mathematics, mainstreaming, and computer-assisted instruction. They give practical suggestions and examples of how to do so. This combination of why and how may be especially helpful and interesting to teachers. Although teachers will find the book interesting, it falls somewhat short of its aims. The book is aimed at being a practical guide to issues, ideas, trends, and instructional procedures for structuring cooperative learning. Too little practical advice is given to help teachers get started with (and sustain) cooperative learning in their classrooms. The book is more a series of essays with practical suggestions added. Finally, the price of the book seems high for its number of pages. (PsycINFO Database Record (c) 2006 APA, all rights reserved) Related Topics Related Articles Classroom Participation: A Model of Feminist Pedagogy Nurse Educator 2018; 43(5): 267–271. Bringing Television Into the Classroom Nurse Educator 2018; 43(3): 153. The flipped classroom The Clinical Teacher 2017; 14(4): 301–302. Cooperation in the classroom Search by title, author, DOI, PMID or keyword  Advanced Search  History Lesson: Vaccine Trials in the Classroom American Journal of Public Health 2018; 108(8): 976-977. ‘Flipping’ the Classroom AJN, American Journal of Nursing 2016; 116(9): 52–56. About us Privacy Policy Terms of Use Site Map Copyright © 2019 Ovid Technologies, Inc., and its partners and affiliates. All Rights Reserved. Some content from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. When implementing cooperative learning in the classroom and the school, one major issue becomes, “How well do group members manage conflicts?” Cooperation and conflict go hand-in-hand. The more group members care about achieving the group's goals, and the more they care about each other, the more frequently conflicts will occur. The second is peer mediation in which all students are taught how to negotiate solutions to their conflicts with schoolmates and faculty and how to mediate conflicts among their peers (Johnson and Johnson 1991). When conflicts are managed constructively within a group, class, and school, the stage is set for cooperative learning and the cooperative school to reach their potential. The Cooperative School. I Accept Ovid uses cookies and similar techniques to improve the functionality and performance of this website and our services. These cookies allow us to track your behavior on – and possibly off – our website. By continuing your use of this website, you consent to this use of cookies and similar technologies.

Nondimensional transport scaling in the Tokamak Fusion Test Reactor: Is tokamak transport Bohm or gyro‐Bohm?

Abstract: General plasma physics principles state that power flow Q(r) through a magnetic surface in a tokamak should scale as Q(r)= {32π2Rr3Te2c nea/[eB (a2−r2)2]} F(ρ*,β,ν*,r/a,q,s,r/R,...) where the arguments of F are local, nondimensional plasma parameters and nondimensional gradients. This paper reports an experimental determination of how F varies with normalized gyroradius ρ*≡(2TeMi)1/2c/eBa and collisionality ν*≡(R/r)3/2qRνe(me/ 2Te)1/2 for discharges prepared so that other nondimensional parameters remain close to constant. Tokamak Fusion Test Reactor (TFTR) [D. M. Meade et al., in Plasma Physics and Controlled Nuclear Fusion Research, 1990, Proceedings of the 13th International Conference, Washington (International Atomic Energy Agency, Vienna, 1991), Vol. 1, p. 9] L‐mode data show F to be independent of ρ* and numerically small, corresponding to Bohm scaling with a small multiplicative constant. By contrast, most theories predict gyro‐Bohm scaling: F∝ρ*. Bohm scaling implies that the largest scale size f...

Positive End-Expiratory Pressure Increases the Right-to-Left Shunt in Mechanically Ventilated Patients with Patent Foramen Ovale

Abstract: Objective: To determine the effect of the presence of a patent foramen ovale on the right-to-left shunt in patients with respiratory failure who receive positive end-expiratory pressure (PEEP). Des...

Impact of Cooperative and Individualistic Learning on High-Ability Students' Achievement, Self-Esteem, and Social Acceptance

Abstract: The effects of cooperative and individualistic learning on the achievement and attitudes of high-ability students were compared. Thirty-four high-ability U.S. students were randomly assigned to a cooperative or an individualistic learning condition. The students, who participated in six 55-min instructional sessions, were presented with the same science lessons, and the teachers were rotated across conditions. The achievement of the high-ability students in the cooperative condition was higher on both recall and higher level reasoning measures than that of their counterparts in the individualistic condition. Also, the high-ability students demonstrated higher academic self-esteem and greater cohesion in the cooperative condition.

Deposition system for the synthesis of modulated, ultrathin-film composites

Abstract: We have initiated a program using elemental superlattices as probes of the early stages of solid‐state reactions. The main advantage of using superlattices as reactants is the ability to tailor their structure on an angstrom length scale to control reaction kinetics. Consequently, we designed and constructed a computer‐controlled and monitored ultrahigh‐vacuum chamber for the preparation of elemental superlattices. This system is capable of manufacturing three sets of three samples in one evacuation cycle. Up to six different elements can be incorporated into each sample. Elements can be deposited from independently controlled electron‐beam sources, Knudsen, or evaporation cells. The sample drive mechanism combined with source shutters and computer control permit complex layer‐repeat units within the composite. Layer thicknesses can be controllably varied from 4 A upward. Various attributes of the chamber include its modular design, multiple layer thickness control options, reproducibility and quality of samples, flexibility, and extensive computer monitoring during sample preparation.

Land grid array package

Abstract: A combination heat sink (18, 41, 43) and circuit interface comprises a metallic wafer (15) disposed between an integrated circuit (11) and a printed circuit board (14) in a land grid array package (10). A frame (13) for the integrated circuit (11) is nested within the heat sink (18, 41, 43) and a latch (30) is pivotably mounted on the frame (13) for retaining the overall package (10). The circuit interface comprises a plurality of flexible electrical connectors (19) mounted on the wafer (15).

Formic acid is a product of the α-oxidation of fatty acids by human skin fibroblasts: deficiency of formic acid production in peroxisome-deficient fibroblasts

Abstract: Human skin fibroblasts in culture can oxidize beta-methyl fatty acids, such as phytanic acid and 3-methylhexadecanoic acid, to CO2 and water-soluble products. The latter are released largely into the culture medium. The major water-soluble product formed from [1-14C]phytanic and [1-14C]3-methylhexadecanoic acids is [14C]formic acid. As phytanic acid and 3-methylhexadecanoic acids contain beta-methyl groups and theoretically cannot be degraded by beta-oxidation, we postulate that formic acid is formed from fatty acids by alpha-oxidation. The marked reduction in formic acid production from beta-methyl fatty acids in peroxisome-deficient skin fibroblasts suggests that peroxisomes are involved in the generation of C1 units.

Creative and Critical Thinking Through Academic Controversy

Abstract: Although creative controversy often occurs naturally within cooperative learning groups, it may be considerably enhanced when teachers structure academic controversies This involves dividing a cooperative group into two pairs and assigning them opposing positions The pairs then develop their position, present it to the other pair, listen to the opposing position, engage in a discussion in which they attempt to refute the other side and rebut attacks on their position, reverse perspectives and present the other position, and then drop all advocacy and seek a synthesis that takes both perspectives and positions into account It is vital for citizens to seek reasoned judgment on the complex problems facing our society Especially important is educating individuals to solve problems for which different points of view can plausibly be developed To do so individuals must enter empathetically into the arguments of both sides of the issue and ensure that the strongest possible case is made for each side, and a

Effects of cooperative and individualistic learning on prospective elementary teachers' music achievement and attitudes.

Abstract: The effects of cooperative and individualistic learning on the achievement and attitudes of prospective elementary school teachers (non-music majors) in a course in music teaching methods were examined. Forty-three American college students were randomly assigned to conditions stratified on the basis of previous musical experience. Cooperation promoted higher achievement than did individualistic efforts on assignments for which each student's grade was affected by the quality of groupmates' work. In addition, students in the cooperative condition were off-task academically (such as walking around the room) less frequently, initiated fewer interactions with the instructor, perceived the instructor to be more supportive, perceived the grading system to be fairer, and perceived the feedback received as being more helpful.

Helium, iron, and electron particle transport and energy transport studies on the Tokamak Fusion Test Reactor

Abstract: Results from helium, iron, and electron transport studies on the Tokamak Fusion Test Reactor (TFTR) [Plasma Phys. Controlled Nucl. Fusion Res. 26, 11 (1984)] in L‐mode and supershot deuterium plasmas with the same toroidal field, plasma current, and neutral beam heating power are presented. They are compared to results from thermal transport analysis based on power balance. Particle diffusivities and thermal conductivities are radially hollow and larger than neoclassical values, except possibly near the magnetic axis. The ion channel dominates over the electron channel in both particle and thermal diffusion. A peaked helium profile, supported by inward convection that is stronger than predicted by neoclassical theory, is measured in the supershot. The helium profile shape is consistent with predictions from quasilinear electrostatic drift‐wave theory. While the perturbative particle diffusion coefficients of all three species are similar in the supershot, differences are found in the L mode. Quasilinear theory calculations of the ratios of impurity diffusivities are in good accord with measurements. Theory estimates indicate that the ion heat flux should be larger than the electron heat flux, consistent with power balance analysis. However, theoretical values of the ratio of the ion to electron heat flux can be more than a factor of 3 larger than experimental values. A correlation between helium diffusion and ion thermal transport is observed and has favorable implications for sustained ignition of a tokamak fusion reactor.

Pluggable connector systems for flexible etched circuits

Abstract: A pluggable connector system (10) has a male housing (11, 11', 11", 11"') snapped together with a female housing (12, 12', 12", 12"') thereby providing a quick-disconnect feature. One of the housings, or both, carries a flexible etched circuit (16). The flexible etched circuit (16) may engage another flexible etched circuit (16) or, via a suitable interface, may engage a printed circuit board (17) having at least one circuit pad (19) thereon. One embodiment of a suitable interface is a flexible electrical connector (21) having a plurality of circuit traces on an elastomeric core. In another embodiment, the flexible etched circuit (16) is backed up by resilient means (33, 35) and engages the circuit pad (19) directly. The means for releasably retaining the housings (11, 11', 11", 11"' and 12, 12', 12", 12"') comprises a pair of spring-loaded manually-releasable latches (24, 24', 25) or a pair of bifurcated latching ears (43, 44).

Flexible circuit interface for coplanar printed circuit boards

Abstract: An interface for connecting coplanar printed circuit ("PC") boards (10, 20) using a flexible jumper circuit (50) for bridging the PC boards (10, 20), a base (80) underlying the second PC board and integrally attached thereto, and a support housing (30) with compression plugs (60) which may be tightened against base (80) for securing the two PC boards (10, 20) and for compressing the flexible jumper circuit (50) against the two PC boards (10, 20). The interface is precision aligned by a plurality of guide pins (34) which protrude from support housing (30) and conform to guide holes in the two PC boards (10, 20) and the flexible jumper circuit (50). Guide pins (34) fix the relative positions of the boards (10, 20) and circuit (50) within their respective planes. The resilient compression plugs (60) maintain contact between the flexible jumper circuit (50) and the two PC boards (10, 20) despite irregularities in thickness, and the guide pins 34 maintain precision horizontal alignment between the contact pads (12, 22) on the two PC boards (10, 20) and the conductive traces (52) on the flexible jumper circuit (50).

Backplane connector utilizing flexible film circuitry

Abstract: The invention is directed to an electronic assembly, such as a backplane assembly of the type including a mother board, a connector housing mounted on the mother board, and a daughter board slidably insertable into the connector housing for electrical interconnection to the mother board. The assembly comprises an elongated connector housing having a pair of parallelly disposed spaced apart housing members defining at least one slot therebetween for receiving the daughter board. A force generating member is disposed within the slot, where the force generating members comprises a pair of resilient, essentially L-shaped members. One leg of each of the L-shaped members is fixedly disposed between the mother board and the housing members, while the others of the legs upstand within the slot in a spaced apart relationship to receive the daughter board therebetween, the upstanding legs including at least one pair of opposing elastomeric members to apply a compressive pressure to said daughter board. Further, a flexible circuit element is mounted on the force generating member and is operatively disposed to electrically interconnect the daughter board to the mother board. A preferred feature thereof is the provision of a camming means on the upstanding legs to allow insertion of the daughter board without causing damage to the circuitry on the flexible circuit element, preferable in the form of a flat film.

Coplanar computer docking system

Abstract: The invention hereof relates to electronic apparatus, such as a computer docking connector. More particularly, the invention relates to a docking connector for edge mounting to a "mother" board, where a "daughter" board, memory card, or similar device is inserted into said connector to electrically interconnect the mother board to the inserted device. The apparatus comprises a pair of spring biased, hermaphroditic, resilient housing members, which when assembled define an elongated slot planarly aligned with an edge of the mother board. Opposed camming surfaces are provided with the slot to operatively spread the housing members upon insertion of the electronic device int the slot. Finally a flexible film member containing electrical circuitry thereon is mounted within the housing members for electrically interconnecting corresponding circuitry on the mother board and the electronic device.

Impact of Cooperative Learning on Naval Air Traffic Controller Training

Abstract: The impact of cooperative learning, compared with the impact of traditional navy instruction, on achievement, performance, attrition rate, and attitudes of American navy air traffic controller trainees was investigated. A class of 12 air traffic controller trainees participated in a cooperative learning condition during the Charts and Publications unit of their training. The unit lasted for 4 1/2 days (8 hr a day). The class's performance was compared with the achievement and success rate of 50 other classes (49 previous and 1 subsequent) that were studying the same unit. Compared with traditional instruction, cooperative learning resulted in greater independent functional ability to perform job functions, and a 0 failure rate.

Combination heat sink and housing for flexible electrical connector used in an electrical or electronic assembly

Abstract: A unitary heat sink and connector housing (10, 10', 10", 10"') is disposed between a pair of electrical members, such as printed circuit boards (11, 12, 31) and/or flexible etched circuits (32) in an overall assembly used in a variety of high-performance miniaturized electronic products. One or more flexible electrical connectors (21, 25, 26, 29, 30) are mounted within the unitary heat sink and connector housing (10, 10', 10", 10"') and provide a circuit interface between respective circuit elements or pads (13, 14) on the printed circuit boards (11, 12, 31) and/or flexible etched circuits (32), respectively. The unitary heat sink and connector housing (10, 10', 10", 10"'), which preferably has heat-radiating fins (20), is made from a material which is thermally conductive but electrically non-conductive. Examples of such a material are anodized aluminum, silicon dioxide and beryllium oxide. Any suitable ceramic material could be used.

Computer docking stations and devices slidably inserted therein

Abstract: A docking station (10) slidably receives a device (12) to provide make, break or tap functions, respectively, in a circuit interface. The circuit interface includes a pair of connector housings (17, 18) provided with flexible (or compressible) electrical connectors (19, 20), respectively. A camming member (28, 29; 31, 32; 44) separates the connector housings (17, 18) as the device (12) is slidably inserted into the docking station (10), thereby assuring a substantially zero insertion force on the circuit interface. Preferably, the circuit interface is between the flexible electrical connectors (19, 20), a printed circuit board (13), and a flexible etched circuit (15). The flexible etched circuit (15) is provided with a stiffener (24) resiliently biased by springs (27).

Effect of structural incoherence on the low‐angle diffraction pattern of synthetic multilayer materials

Abstract: The sequential, layering techniques used to prepare multilayer materials result in significant structural incoherence due to deviations from the intended thicknesses within an elemental layer and local deviations from the average due to islanding of the depositing elements during deposition. We demonstrate that if the domain size of the structural incoherence is large compared with the wavelength of the scattering radiation, the structural incoherence manifests itself in the low‐angle diffraction pattern by attenuating the intensity of the subsidiary maxima relative to the Bragg maxima. We also show that the subsidiary maxima in the low‐angle diffraction pattern of a multilayer result from incomplete destructive interference from all of the interfaces, not just from the top and bottom surface of the film. A technique for incorporating structural incoherence when modeling the diffraction pattern of a multilayer structure is presented. The ability of this model to simulate the experimental diffraction pattern of an iron‐silicon multilayer is demonstrated.

The Impact of Cooperative Learning on the Performance and Retention of U.S. Navy Air Traffic Controller Trainees

Abstract: The impact of cooperative learning, compared with traditional navy instruction, on achievement, performance, attrition rate, and attitudes of U.S. Navy air traffic controller trainees was investigated. A class of 13 air traffic control trainees participated in the cooperative condition for the charts and publications unit of their training. The performance for this class was compared with that of 50 other classes who studied the same unit. Cooperative learning, compared with traditional instruction, resulted in greater learning of technical information, greater independent functional ability to perform job functions, and a zero failure rate. In addition, cooperation, compared with traditional instruction, resulted in greater esprit-de-corps and more favorable perceptions of the instructor's competence.

High poloidal beta long‐pulse experiments in the Tokamak Fusion Test Reactor*

Abstract: Experiments have been performed in the Tokamak Fusion Test Reactor [D. M. Meade et al. in Plasma Physics Controlled Nuclear Fusion Research, 1990 (International Atomic Energy Agency, Vienna, 1991), Vol. 1, p. 9] with neutral beam injection of up to 4 sec. duration, which is comparable to the time scale for resistive redistribution of the plasma current profile. These plasmas were created using a rapid decrease of the plasma current which initially created a plasma with enhanced stability and confinement. As the current profile evolved, a significantly reduced beta limit was observed. The high eβp plasmas had up to 90% of the current driven noninductively which significantly broadened the current profile during the long pulse lengths. These experiments demonstrated that high βN plasmas could not be sustained for times longer than the resistive relaxation of the outer current region which at early times after the current ramp‐down carried negative current. At later times in lower βN discharges, beta collaps...

Effects of temperature on muscle pHi and phosphate metabolites in newts and lungless salamanders.

Abstract: The effect of acute alterations in body temperature (BT) on intracellular pH (pHi) and phosphate metabolites was assessed in white skeletal muscle of intact newts and lungless red-backed salamanders using 31P-nuclear magnetic resonance spectroscopy. pHi decreased with increasing BT in the tail muscle of both newts and lungless red-backed salamanders. The change in pH with change in temperature from 10 to 30 degrees C was -0.018 U/degrees C in newts and -0.041 U/degrees C in red backs. The calculated alpha-imidazole for skeletal muscle cytosol did not change (0.56) in newts from 10 to 30 degrees C but fell from 0.69 to 0.43 in red-backed salamanders. Phosphocreatine (PCr)/Pi fell and Pi/beta-ATP rose with increasing temperature in both newts and red backs; however, the change was much greater in red backs. Providing the red backs with O2 at 30 degrees C led to higher pH and alpha-imidazole, comparable to that of newts, along with increased PCr/Pi and lower Pi/beta-ATP. Thus newts maintain white skeletal muscle cell cytosol alpha-imidazole constant with changes in BT, whereas red backs apparently do not. However, at the BT of preference, red backs and newts maintain similar muscle pHi and alpha-imidazole. The method of gas exchange appears to strongly influence the ability of an animal to maintain its acid-base status over a range of temperatures, and our results suggest that behavioral regulation of BT may involve alpha-imidazole regulation as well.

Ion cyclotron range of frequency heating on the Tokamak Fusion Test Reactor

Abstract: The complete ion cyclotron range of frequency (ICRF) heating system for the Tokamak Fusion Test Reactor (TFTR) [Fusion Tech. 21, 1324 (1992)], consisting of four antennas and six generators designed to deliver 12.5 MW to the TFTR plasma, has now been installed. Recently a series of experiments has been conducted to explore the effect of ICRF heating on the performance of low recycling, supershot plasmas in minority and nonresonant electron heating regimes. The addition of up to 7.4 MW of ICRF power to full size (R∼2.6 m, a∼0.95 m), helium‐3 minority, deuterium supershots heated with up to 30 MW of deuterium neutral‐beam injection has resulted in a significant increase in core electron temperature (ΔTe=3–4 keV). Simulations of equivalent deuterium–tritium (D–T) supershots predict that such ICRF heating should result in an increase in βα(0)∼30%. Direct electron heating has been observed and has been found to be in agreement with theory. The ICRF heating has also been coupled to neutral‐beam heated plasmas f...

Cervical self-manipulation and stroke

Abstract: Neck manipulation, especially self-manipulation, should be considered as one of the risk factors for stroke in the young, and the practice of encouraging patients to perform cervical self-manipulation should be strongly discouraged.

ICRF heating on TFTR-effect on stability and performance

Abstract: With the addition of two new antennas and two radiofrequency (RF) generators, the TFTR ICRF system is complete. The total complement of four antennas and six generators is designed for 12.5 MW operation. Experiments with this system have been performed recently on TFTR in the low recycling regime to increase the performance of supershot plasmas, in a non-resonant regime to explore electron heating, and in high recycling discharges with energetic ion tails to simulate fusion alpha particles. Noteworthy results include: direct electron heating observed with absorption rates in agreement with theory; electron heating of supershot plasmas ({Delta}TEO {approximately} 2 key) via energetic ion tails that would increase the pressure of the alpha particles in DT plasmas; and the first observation of the toroidal Alfven eigenmode (TAE) instability driven by the energetic ion tail in hydrogen minority heating.

Starting Positions: The Social Function of Literature in the Cape

Abstract: Arguments about the social function of literature in South Africa have their origins in the public lectures and literary journals of the Cape Colony in the first half of the nineteenth century. Four overlapping positions can be distinguished: the missionary position, which sees imaginative literature as a proselytising aid and an occasional substitute for the Scriptures; the utilitarian position, which sees it of limited use value in the emergent capitalist social order; the romantic position, which sees it as a repository of profound spiritual truths; and the imperial position, which sees English literature as a means of constructing and securing national identity. Looking at a diverse range of contemporary arguments about literature, from those of figures like Albie Sachs to those of institutions like the Censorship Board and the Shakespeare Society of Southern Africa, connections between the early and more recent positions are suggested. Though there are no simple continuities from the 1820s to the 199...