Showing papers by "University of Maryland, Baltimore County published in 1972"
TL;DR: In this article, a forced choice procedure was used to obtain confusion matrices for 22 patients on four sets of nonsense syllables, using a forced-choice procedure and two multidimensional scaling procedures, MDSCAL and IND-SCAL.
Abstract: Confusion matrices were obtained for 22 patients on four sets of nonsense syllables, using a forced‐choice procedure. Each syllable set considered of 16 consonants in combination with the vowels /i,a,u/ either in CV or VC form. Syllables were presented at a comfortable listening level approximately 40 dB above the audiologic SRT. Over‐all performance varied as a function of syllable set, vowel, and hearing loss. The confusions were analyzed by two multidimensional scaling procedures, MDSCAL and IND‐SCAL. In addition, an iterative feature analysis of transmitted information was performed, in which the feature system of Miller and Nicely and Chomsky and Halle were compared. [Research supported by grants from SRS and NINDS.]
104 citations
TL;DR: It is concluded that PBP1 interacts with the bacterial flagellum during the adsorption process and mediates generalized transduction in BpB1 at a frequency on the order of 10−8 transductants per plaque-forming unit.
51 citations
TL;DR: The authors analyzed vocal intensity in a prior study as an interpersonal cue in verbal communication and found that intensity is both a stable and modifiable characteristic of interpersonal communication and suggests that variations in levels of vocal intensity of conversational partners may convey information about their relationship to each other.
Abstract: The purpose of the present study was to analyze vocal intensity in a prior study as an interpersonal cue in verbal communication Reanalysis indicates that intensity is both a stable and modifiable characteristic of interpersonal communication and suggests that variations in levels of vocal intensity of conversational partners may convey information about their relationship to each other
48 citations
TL;DR: In this paper, the lowest n-π * triplet states of 1-indanone and α-tetralone incorporated substitutionally in a single host of durene have been performed using optical detection at 2.0°K with 35 GHz microwaves.
19 citations
TL;DR: By controlling the ratio of metal ion to ligand concentrations in the DyIII-acetate system, the complexation rate constant for the formation of the bisacetato-complex was found to be significantly larger than for the monoacetato complex as mentioned in this paper.
Abstract: By controlling the ratio of metal ion to ligand concentrations in the DyIII–acetate system, the complexation rate constant for the formation of the bisacetato-complex was found to be significantly larger than for the monoacetato-complex.
12 citations
TL;DR: Virulent bacteriophage MX-1 infection of differentiating M. xanthus cells, after commitment to myxospore formation and before loss of ability to adsorb phage, results in trapping of the phage genome.
9 citations
TL;DR: It appears that the titration of a histidine or an α-amino group results in a loss of binding ability, and the binding of calcium eliminates the self-association of the chymotrypsinogen monomer.
8 citations
TL;DR: E-AMP has been found to function as an activator and e-ATP as an inhibitor, although their binding affinities are less than those of the natural nucleotides, and the catalytic efficiencies of the e-AMP and AMP complexes have be similar.
8 citations
8 citations
TL;DR: It is suggested that certain sites or regions of the BpB1 genome exhibit a high rate of spontaneous mutation.
Abstract: Broth cultures of Bacillus pumilus NRRL B-3275 (BpB1) grown at 25, 30, or 37 C contain 1 to 2% spontaneous auxotrophic mutants in both the exponential and stationary phases of growth. Of 70 such mutants isolated from cultures grown at 37 C, approximately two-thirds reverted at such a high frequency as to preclude their study. Of the remaining 22 mutants, 18 required a single amino acid, 1 required adenine, and 1 required uracil. Two of the auxotrophs each required two unrelated amino acids resulting from two independent mutations. All of the mutations reverted spontaneously. Enhanced reversion of approximately one-third of the mutations was obtained with nitrosoguanidine, ethyl methane sulfonate, or diethyl sulfate, or with more than one of these mutagens. The reversion of one mutation was enhanced by 2-aminopurine. The reversion of the remaining mutations was not enhanced by the above mutagens, nor by mutagens known to induce (and revert) frameshift mutations in other bacterial systems. Nine of 10 mutants examined did not show a selective growth advantage over the parents. All but three of the mutations could be linked by PBS1 transduction to one of the previously described auxotrophic markers in strain BpB1. No evidence was obtained for clustering of the mutations on the BpB1 genome. Six of the mutations conferred a requirement for serine. One linked by transduction to trp-2 , three linked to argA1 , and two ( ser-2, -3 ) linked to argO1 . Pigmented mutants (containing a carotenoid-like pigment), which occur spontaneously in BpB1 cultures at a frequency on the order of 1 to 5 mutants per 10 4 cells, link by transduction to ser-2, -3 . Spontaneous mutants of strain BpB1 resistant to rifampin, streptomycin, erythromycin, 5-fluorouracil, or 5-methyltryptophan occur at a frequency similar to that of strains of B. pumilus which do not exhibit a high rate of spontaneous mutation to auxotrophy. It is suggested that certain sites or regions of the BpB1 genome exhibit a high rate of spontaneous mutation. Images
7 citations
TL;DR: The new mutable allele, w+u, mutates from a wild-type to a white-eyed phenotype in both males and females and favors a model based on the premature termination of chromosome replication near the terminus of a replicon which leads to a chromosome deficient for the material between the point of premature termination and the end of the replicon.
Abstract: The genetics of a third case of high mutation frequency at the white locus in Drosophila melanogaster has been analyzed. The new mutable allele, w
+u, mutates from a wild-type to a white-eyed phenotype in both males and females. The mutational event is 1) premeiotic, 2) not associated with crossingover, 3) sensitive to genetic modification, and 4) restricted to germinal tissue. The only mutants produced by w
+u are deletions of the white locus. These deficiencies include subsites 4 and 5 of the white locus, but are cytologically unobservable. The mutable allele itself maps to subsite 4. The mutational properties of w
+u are unlike those of the other highly mutable white alleles which have been interpreted in terms of phage-like controlling elements. Rather, the properties of w
+u favor a model based on the premature termination of chromosome replication near the terminus of a replicon which leads to a chromosome deficient for the material between the point of premature termination and the end of the replicon.
TL;DR: Several alternative metrics either describing the response pattern in S1 or focusing on some specific component of the pattern are suggested.
Abstract: Summary.-While the disadvantages of absolute measures of the behavioral effects of response rate in [he CER procedure are well-known, there are several often unrecognized difficulties with the use of suppression ratios, the most serious relating to changes in pre-S response rates and to non-uniformity of response rate in the presence of S1. Several alternative metrics either describing rhe response pattern in SI or focusing on some specific component of the pattern are suggested. In the conditioned emotional response (CER) paradigm, response-independent pairings of an initially neutral stimulus, S1, and an aversive stimulus, S2, are superimposed on ongoing responding. The dependent variable in such a procedure is response rate in the presence of S1. Church (1969), in a discussion of the measurement of the suppressive effects of punishment, has noted that absolute S, response rate in itself is an inadequate and perhaps invalid measure; the metric of interest is a relative one which permits a comparison of response rate in the presence of S1 with "normal" or "baseline" suppression ratio (SR) of the form SR = B/(A + B), in which A is pre-S1 response rate and B represents response rate in the presence of S,. While it is clear that z relative measure of suppression is preferable to an expression in absolute terms for a variety of reasons, there are still serious diffic~ilties with the use of SRs. First, it is not always clear when response rate A is to be sampled. While most investigators examine races in a brief period immediately prior to S1 onset, others (e.g., Singh, 1959) report a ratio based on response rate in the control sessions prior to S1-S2 pairings. A second difficulty lies in that there are at least five different "ratios" in common use; B/A (Stein, Sidman, & Brady, 1958), (A - B) /A (Hoffman & Fleshler, 1961), B/ (A + B) (Kamin, 1961), A/(A + B) (Goldstein, 1966), and (B - A)/A (Hunt, Jernberg, & Brady, 1952). Such multiplicity is likely to lead to misinterpretation (see Lyon, 1968). For example, maximum suppression (no responding in the presence of S1) may be indicated by SRs of 0, - 1.0, or + 1.0 depending on the specific formula used, while nonsuppression (pre-S, rates and response rate during S1 are equal) may appear as SRs of 0, 0.5, or 1.0. Furthermore, a variety of pairing procedures (Shimoff, 1970) are associated with increased responding in S1, and the commonly used SRs are even more confusing in expressing response facilitation. If response rate in S1 is twice as high as the pre-S1 rate, SRs
TL;DR: A statistical mechanical treatment is presented which permits interpretation of the various binding coefficients in terms of the characteristic parameters of explicit molecular models.
TL;DR: In this paper, response rates of rats were recorded during a 30-sec signal (CS) which preceded a response independent electric shock when: (1) baseline avoidance shocks were withheld during the signal; (2) baseline avoiding shocks were available during the stimulus; and (3) a response-independent shock was intruded on each trial at the midpoint of the signal.
Abstract: Response rates of rats were recorded during a 30-sec signal (CS) which preceded a response-independent electric shock when: (1) baseline avoidance shocks were withheld during the signal; (2) baseline avoidance shocks were available during the stimulus; and (3) baseline avoidance shocks were withheld but a response-independent shock was intruded on each trial at the midpoint of the signal. Two different adjusting avoidance baselines were used. The data suggest that the signal suppresses responding, but also that this effect can be overcome by shocks supplied either from the baseline schedule or intruded on a response-independent schedule.
TL;DR: In this article, a super-Alfvenic aligned magnetogasdynamic flow over a cone of finite semi-apex angle, with an attached fast shock wave, is solved numerically.
Abstract: Super-Alfvenic supersonic aligned magnetogasdynamic flow over a cone of finite semi-apex angle, with an attached fast shock wave, is solved numerically. We obtain ‘almond curves’ in the plane of magnetic induction vector variation, analogous to Busemann's ‘apple curves’ for supersonic cone flows, to describe the flow field near the cone. Total surface pressure coefficients, current and vorticity distributions are presented. A closed-form solution of the flow is obtained when a switch-on shock occurs.
TL;DR: The fluorescence properties of acriflavine and methylbenz(a)anthracene conjugates of DNA and several biosynthetic polyribonucleotides have been examined and compared and the extent to which rotational mobility was lost at the early stages of complex formation differed for the two labels.
TL;DR: Delegates to a special meeting of the Federal Council of Churches in Columbus Ohio, in March, 1946, adopted a report which committed the Council to work for a non-segregated church in a nonsegregate society and called upon its constituent communions to do likewise.
Abstract: Delegates to a special meeting of the Federal Council of Churches in Columbus Ohio, in March, 1946, adopted a report which committed the Council to work for a non-segregated church in a non-segregated society and called upon its constituent communions to do likewise. The statement represented a new departure, but its timing—coming at the end of the Second World War—was also significant. Although the position of the Federal Council was in advance of any positain yet taken by the major protestant denominations individually, it indicated that American protestantism was beginng to be challenged in a new way by the question of race. In the yers immediately prior to 1939 the denominations paid little attention to race as a social issue: by 1945 it was frequently the subject of denominational pronouncements and editorials in the church press. This contrast in the reponse of the churches suggests that the years of the Second World War had been crucial in placing new pressures upon white attitudes toward black Americans.