Description of Thalassospira lohafexi sp. nov., isolated from Southern Ocean, Antarctica.

A gram-negative, aerobic, obligatory halophilic, curved-to-spiral rod-shaped, uni- or bi-polar flagellated motile bacterium 139Z-12(T) was isolated from water samples collected from Southern Ocean surrounding Antarctica as part of the Indo-German iron fertilization experiment "LOHAFEX." The bacterium was positive for catalase, oxidase, and gelatinase, with C18:1ω7c (20.1 %), C16:0 (7.

Aspartate aminotransferase is involved in cold adaptation in psychrophilic Pseudomonas syringae.

CSM2, a cold-sensitive mutant of psychrophilic Pseudomonas syringae, grows like wild-type cells when cultured at 22 and 28 degrees C; but at 4 degrees C, the growth is retarded. In CSM2, AAT (coding for aspartate aminotransferase) is identified as the mutated gene. The expression of AAT in Pseudomonas syringae was transiently enhanced when cells were shifted from 22 to 4 degrees C indicating that AAT is cold-inducible.

Importance of trmE for growth of the psychrophile Pseudomonas syringae at low temperatures.

Transposon mutagenesis of Pseudomonas syringae Lz4W, a psychrophilic bacterium capable of growing at temperatures between 2 and 30 degrees C, yielded 30 cold-sensitive mutants, and CSM1, one of these cold-sensitive mutants, was characterized. Growth of CSM1 was retarded when it was cultured at 4 degrees C but not when it was cultured at 22 degrees C and 28 degrees C compared to the growth of wild-type cells, indicating that CSM1 is a cold-sensitive mutant of P. syringae Lz4W.

Perceptual recalibration in human sound localization: learning to remediate front-back reversals.

The efficacy of a sound localization training procedure that provided listeners with auditory, visual, and proprioceptive/vestibular feedback as to the correct sound-source position was evaluated using a virtual auditory display that used nonindividualized head-related transfer functions (HRTFs). Under these degraded stimulus conditions, in which the monaural spectral cues to sound-source direction were inappropriate, localization accuracy was initially poor with frequent front-back reversals (source localized to the incorrect front-back hemifield) for five of six listeners. Short periods of training (two 30-min sessions) were found to significantly reduce the rate of front-back reversal responses for four of five listeners that showed high initial reversal rates.

Hamster contraception associated protein 1 (CAP1).

Based on cDNA and amino acid sequence, we demonstrate that hamster contraception associated protein 1 (CAP1) protein (an homolog of DJ-1 in mouse, CAP1/SP22/RS in rat and DJ-1/RS in human) is conserved during evolution. Through solubilization studies, it was demonstrated that hamster CAP1 has a peripheral membrane localization. SDS-PAGE analysis revealed that the migration pattern for hamster CAP1 compared to the other rodent counterparts, rat and mouse was different; indicating species-specific differences in the protein (possibly due to post-translational modifications).

Expression and cellular localization of contraception-associated protein.

Treatment of male rats with ornidazole results in reversible infertility, which is associated with the detection of the contraception-associated protein 1 (CAP1) in epididymal fluid. The protein, which is present in sperm but not detectable in epididymal fluid of fertile rats, seems to be shed from sperm during ornidazole administration. Cloning and characterization of the gene revealed a high degree of similarity between CAP1 and DJ-1 (Wagenfeld et al, 1998b) a protein that was recently found in humans and which has been classified as a novel oncogene.

Adaptive computational models of fast learning of motion direction discrimination.

In a previous study, we found that subjects' performance in a task of direction discrimination in stochastic motion stimuli shows fast improvement in the absence of feedback and the learned ability is retained over a period of time. We model this learning using two unsupervised approaches: a clustering model that learns to accommodate the motion noise, and an averaging model that learns to ignore the noise. Extensive simulations with the models show performance similar to psychophysical results.

Learning to ignore: psychophysics and computational modeling of fast learning of direction in noisy motion stimuli.

The effects of practice on the discrimination of direction of motion in briefly presented noisy dynamic random dot patterns are investigated in several forced-choice psychophysical tasks. We found that the percentage of correct responses on any specific task increases linearly with repetition of trials within roughly 200 trials from about chance to a performance of 90% or better. The level of performance remained constant or improved over several days, and in most instances it did not transfer when stimulus parameters changed.