Alexithymia and Impairment of Decoding Positive Affect: An fMRI Study

Previous research has implicated alexithymia as a psychological impairment to accurately decode emotional messages. This study attempted to explore potential neurological reasons for this impairment. Using functional brain imaging procedures, an experimental design was undertaken to assess group differences between individuals high and low in alexithymia on brain activation while viewing images of individuals displaying neutral or positive affect. While controlling for activation due to neutral affect images, results showed less activation for alexithymic versus nonalexithymic individuals due to positive affect images in several areas of the brain, including the amygdala and the hippocampus. Several implications and directions for future research are also discussed.     

Simulation of a novel, optically addressable,switched-current/continuous-time, current-mode cellular neural network

The authors describe simulation results of a novel GaAs-based current-mode cellular neural network (CNN) connected component detector. It uses a new two-stage integrator which may be operated in switched-current or continuous-time mode. Our system approach would afford CNN parallel optical input and output     

Changes in Students' Attitudes as a Result of Participating in a Simulated Game.

This study examined the effects of participating in a noncomputerized simulation on students' attitudes toward civic responsibility and community integration. Four sections of a business policy course each having 25-30 college seniors were divided into two control and two experimental groups. The experimental groups participated for 5 weeks in SIMSOC (simulated society), a game that simulates an entire open society. Pre- and posttest measures were collected, using Bosworth's Community Attitude Scale. Significant changes in attitudes toward community integration were found for the experimental groups. There were not significant changes for the experimental groups on the Civic Responsibility scale. The entire population scored higher on the Civic Responsibility scale than that population which participated when the scale was first validated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Using subordinate ratings to elicit behavioral changes in supervisors.

Determined whether feedback of subordinates' ratings of supervisors leads to positive changes in the supervisors' behavior. The employees of the 56 supervisors in the experimental and control groups completed an information-opinion survey using a modified Likert scale format. Feedback reports were given to the experimental supervisors, and a 2nd survey was conducted 10 wks later to measure change. 2 independent measures showed significant positive change for the experimental supervisors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Noise properties of a Raman amplifier

We present the first measurements of the noise properties of a Raman optical amplifier. Measurements on CW Raman amplified optical signals from a 1.5-μm single frequency laser in 32 km of silica fiber, pumped by a 1.45-μm color center laser, reveals that the main noise source is the shot noise generated in the receiver due to the spontaneous Raman radiation. For signal levels down to -50 dBm, no excess noise due to the Raman process could be detected.     

Three-frequency Chaos in an External Cavity Injection Laser

Abstract

We report fixed-frequency interactions in a modulated delay system. In particular, we have observed frequency locking, quasiperiodicity and the progression to a chaotic state by the collapse of a three-frequency quasiperiodic attractor, characteristic of the Ruelle-Takens-Newhouse scenario, in a modulated two-sided external cavity injection laser. While the temporal and spectral characteristics of the laser emission suggest that the laser has progressed to a chaotic state, dimensionality testing of the laser output is inconclusive.     

Operation of an optoelectronic crossbar switch containing a terabit-per-second free-space optical interconnect

The experimental operation of a terabit-per-second scale optoelectronic connection to a silicon very-large-scale-integrated circuit is described. A demonstrator system, in the form of an optoelectronic crossbar switch, has been constructed as a technology test bed. The assembly and testing of the components making up the system, including a flip-chipped InGaAs-GaAs optical interface chip, are reported. Using optical inputs to the electronic switching chip, single-channel routing of data through the system at the design rate of 250 Mb/s (without internal fan-out) was achieved. With 4000 optical inputs, this corresponds to a potential aggregate data input of a terabit per second into the single 14.6 /spl times/ 15.6 mm CMOS chip. In addition 50-Mb/s data rates were switched utilizing the full internal optical fan-out included in the system to complete the required connectivity. This simultaneous input of data across the chip corresponds to an aggregate data input of 0.2 Tb/s. The experimental system also utilized optical distribution of clock signals across the CMOS chip.