The relationship between loudness and reaction time in normal hearing listeners

Equal-loudness contours were constructed from magnitude estimation judgements in 10 normal-hearing listeners. Equal-latency contours were constructed from auditory reaction time measurements in these same listeners. the stimuli were pure tones ranging from 250-4000 Hz in octave intervals. Equal-loudness contours were in good agreement with those obtained by previous researchers, and the equal-latency curves were in good agreement with the equal-loudness contours.

Some characteristics of an early protein (ICP 22) synthesized in cells infected with herpes simplex virus

In Vero cells incubated at 40 degrees C or treated with azetidine at 37 degrees C, synthesis of a polypeptide ('C') of apparent mol. wt. 66000 was stimulated. It was not phosphorylated and was found in the cytoplasmic fraction of cell lysates. In cells infected with herpes simplex virus type 1 (HSV-1) in the presence of azetidine, synthesis of cellular proteins, including polypeptide C, was suppressed and infected cell polypeptides ICP 4, 0, 22 and 27 (apparent mol. wt. 170000, 120000, 75000 and 60000, respectively) were made. All were phosphorylated and accumulated in the nucleus. Messenger RNA for the same four polypeptides was made in cells infected in the presence of cycloheximide. Thus, ICP 22 is distinct from cellular polypeptide C and is probably a virus-specific alpha polypeptide, although it differs from alpha ICP 4, 0 and 27 in that its rate of synthesis does not decline rapidly when later polypeptides are produced. It is modified after synthesis in at least two steps, the second of which may require a later virus-specific polypeptide. In cells infected with HSV-2 the synthesis of a polypeptide analogous to ICP 22 could not be detected.

Loudness growth of musically complex stimuli

Young adults (N = 11) with musical training, and with previous practice in the use of direct magnitude estimation of loudness for pure tones, judged the loudness of 3 orchestral excerpts each lasting 15-25 sec, varied in 5 -db steps over a 35 -db range. Excerpt I was relatively constant in both pitch and loudness; Excerpt II varied in loudness but did not change greatly in pitch; and Excerpt III changed both in pitch and loudness. The slopes of power functions for loudness judgments as a function of SPL fell within the usual range for pure-tone and for white-noise stimuli, as did indexes of determination; but both measures differed significantly from those in the literature for continuous speech. Apparently the acoustic variability in speech is an insufficient explanation for the difference between speech and non-speech stimuli in these areas, a finding which points to the contribution of non-acoustic parameters, such as semantic meaning, in loudness judgments for speech.

Detection of Bacterial Kidney Disease in Wild Salmonids in the Margaree River System and Adjacent Waters Using an Indirect Fluorescent Antibody Technique

The indirect fluorescent antibody technique demonstrated the enzootic nature of bacterial kidney disease in 224 of the 605 wild salmonids sampled from the Margaree River system and some adjacent waters. Asymptomatic infections were observed in 33.4% of 456 Atlantic salmon (Salmo salar) parr and 35.1% of 37 returning adults in samples taken from the source of the Margaree River to and including saltwater areas off the coast. Key words: kidney disease, Atlantic salmon, wild, distribution, fluorescent antibody

Changes in number and type of errors on repetition of acoustically distorted sentences as a function of age in normal children

The intelligibility of recorded sentences, distorted by binaural switching, interruption, and low-pass filtering, was investigated in 53 children ranging in age from five to eleven and in adults. All had normal hearing. The sentence vocabulary was pretested for comprehension, articulation errors were evaluated in a way so as not to influence test results, and length and structure of the sentences were controlled. The results indicated that although the performance of children increased with age, the 11-year-old group had not attained adult performance. Error analyses showed that most errors for all age groups were acoustically unrelated to the distorted message, although adults made more acoustically related errors than did children. When children made errors in sentences, other errors (e.g., substitutions) were made to preserve the syntax or semantic integrity of the message.

Characteristics of calcification in tumors of the pineal gland

Thirty-two cases of proved pineal tumor were analyzed. Calcification was seen in 75%. The size, character, and position of the calcification were useful indicators of abnormality on plain-film evaluation. Fray's cranioangle method was more sensitive than Oon's method in determining abnormal position of the calcified pineal tumor on the lateral skull film. Most calcifications were displaced postero-inferiorly or inferiorly, which can be explained by obstructive hydrocephalus or direct tumor expansion.

Anticipatory middle-ear reflex activity from noisy toys

Middle-ear reflex activity was measured in 14 listeners in response to visual and acoustic exposure to each of seven noisy toys (such as a cap gun, party horn, cow bell, and so forth). Anticipatory middle-ear reflex (AMER) activity was a common occurrence. Normal middle-ear reflex generally occurred after the sound exposure. AMERs generally occurred in the two seconds prior to sound exposure but as early as 10 seconds before sound exposure. Loudness ratings and exposure SPLs were obtained. The presence of acoustically evoked middle-ear (ME) reflex activity and AMERs to the toys was generally unrelated to SPL or reflex threshold. Many reflex responses occurred in response to exposure SPLs below reflex threshold and with low anticipated loudness rating.

Enzyme increase by folate and methotrexate in cultured mammalian cells

Folate and methotrexate markedly increased the activity of dihydrofolate reductase in cultured cells of human origin. Folate did not have this effect in the cells of other species tested, whereas methotrexate increased enzyme activity in some other species. Neither compound increased enzyme activity in a somatic hybrid, although such an increase occurred in one of the parent cell lines. Active enzyme synthesis appeared necessary for the effect of folate to occur. Degradation of the increased enzyme after cycloheximide treatment of cells proceeded at least as rapidly as in control cultures and was associated with a decrease in the intracellular folate pool, whereas folate added after 48 h of culture stabilized the enzyme at this same intracellular concentration. Folate, added at 24 h of culture, produced the greatest increase in activity, but the subsequent rate of decrease was greater than that when folate was added at 48 h, although the intracellular concentration of folate in the latter case was only half that in the former.

Temporary threshold shift from a toy cap gun

Temporary threshold shift resulting from exposure to one and five toy cap gun pistol shots was investigated using 11 normal-hearing adult subjects and one subject with a noise-induced hearing loss. The subjects fired the cap gun at arm’s length, and absolute thresholds at 4000 Hz were obtained before and after noise exposure by a fixed-frequency Bekesy technique. After exposure to one gunshot, five subjects showed a small TTS, five demonstrated no TTS, and two (including the subject with the hearing loss) exhibited negative TTS. No TTS occurred in any of the subjects after exposure to five shots. It was postulated that the small amount of TTS was due to the unexpectedly low sound pressure level produced by the cap gun and to the contraction of the middle ear muscles in some subjects prior to firing.

Purification and properties of dihydrofolate reductase from cultured mammalian cells

Dihydrofolate reductase was purified quickly and simply from small quantities of cultured mammalian cells by affinity chromatography. On gel electrophoresis of the purified enzyme, multiple bands of activity resulted from enzyme-buffer interaction at low but not high buffer concentration. A Ferguson plot (Ferguson, 1964) showed that this heterogeneity was due to a charge difference with no alteration in the size of the enzyme. Stimulation of enzyme activity by KCl, urea and p-hydroxymercuribenzoate, and inhibition by methotrexate and trimethoprim, showed only minor differences between the various enzymes.