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The article presents information on the socioeconomic model related to national Olympic performance. It determines whether communist countries have performed better than noncommunist countries after allowance is made for key demographic and economic factors. Subsidiary purposes are to suggest an approach for investigating the impact of political systems on the sports and other spheres of activity, to present evidence on "n-achievement," and to suggest new avenues of research. This model was used to explain the results of the 1972 Olympic Games. The model is a successful representation of the effects of selected variables on Olympic performance. But only 70 percent of the variance in the actual medal series is explained in the article. Among the non-communist countries, the model has substantially underpredicted the winnings of some countries and overpredicted the winnings of others. There are similar, though less severe, discrepancies for communist countries. Some of the discrepancies must be due to unquantifiable variables.

Focuses on the crisis management on oil industry in Great Britain. Uses of petroleum products; Financial estimation on the destruction at Balku Oil fields; Shortages for the domestic market.

This study compared the reliability of a recently developed high-frequency audiometer (HFA) [Stevens et al., J. Acoust. Soc. Am. 81, 470-484 (1987)] with a less complicated system that uses supraaural earphones (Koss system). The new approach permits calibration on an individual basis, making it possible to express thresholds at high frequencies in dB SPL. Data obtained from 50 normal-hearing subjects, ranging in age from 10-60 years, were used to evaluate the effects on reliability of threshold variance, earpiece/earphone fitting variance, and the variance associated with the HFA calibration process. Without earpiece/earphone replacement, the reliability of thresholds for the two systems is similar. With replacement, the HFA showed poorer reliability than the Koss system above 11 kHz, largely due to errors in estimating the calibration function. HFA reliability is greater for subjects with valid calibration functions over the entire frequency range. When average correction factors are applied to the Koss data in an effort to convert threshold estimates to dB SPL, individual transfer functions are not represented accurately. Thus the benefit of being able to express thresholds at high frequencies in dB SPL must be weighed against the additional source of variability introduced by the HFA calibration process. [ABSTRACT FROM AUTHOR]

Listeners' abilities to discriminate the order of two tones, of frequency 500 Hz and 500 Hz+Δ f, separated by less than 5 ms, were measured in terms of threshold durations (T) for the tones. The experiment was repeated for values of Δ f between 5 and 160 Hz. The relation of the duration threshold to Δ f was well-described by the reciprocity equation, Δ f T=K, for K=0.16. This reciprocity corresponds to a constant overlap of the main lobes of the power spectra for the tones of about 70%-80%. Addition of a trailing context tone severely degraded the ability to discriminate temporal order, increasing the value of the reciprocity constant to approximately K=1.8. The primary effect of the context tones was to increase the duration required for accurate discrimination, rather than to impair actual frequency resolution. Implications of these results for speech perception are discussed. [ABSTRACT FROM AUTHOR]

This is the second in a series of articles in human listeners' abilities to discriminate between word-length tonal sequences, or ''patterns.'' The first article reported that frequency resolution, by highly trained listeners, is four to five times more accurate for high-frequency, late-occurring components of such sequences than for low-frequency early components [Watson, Kelly, and Benbasset, J. Acoust. Soc. Am. 57, 1175-1185 (l975)]. These effects, which are similar to described as ''recognition masking'' or ''informational masking'' by other authors, have now been shown to be strongly dependent on the degree of trial-to-trial stimulus uncertainty of the psychophysical procedure in which they are measured. When stimulus uncertainty is reduced to its psychophysical minimum, frequency resolution for any component of a tonal sequence is only slightly less accurate than for isolated tones. Previous reports of recognition masking this may reflect limitations imposed by those more dynamic parts of the sensory process concerned with memory and attention, rather than information loss in the more static peripheral auditory system. Subject Classification: [43]65.22, [43]65.75, [43]65.64, [43]65.58. [ABSTRACT FROM AUTHOR]

The onset of a noise [0.9-2.1 kHz, 55 dB SPL (A weighted)] preceded that of a buzz [100 Hz, 0.5-3.0 kHz, 70 db SPL (A weighted), 500 msec] by -10 to +80 msec and both terminated simultaneously. Eight adults discriminated among noise-lead times in an oddity task. In separate sessions, they labeled singly presented stimuli with either of the two responses: ''no noise'' or ''noise.'' The results are highly similar to those reported for the categorical perception of synthetic plosive consonants differing in voice-onset time. On the average, discrimination was best across a noise-lead-time boundary of about 16 msec, where labeling also shifted abruptly. These results and those of categorical perception, generally, are interpreted in terms of Weber's law as applied to a single component within a stimulus complex. It is concluded that categorical perception of sounds is not unique to speech and suggested that it may be a general property of sensory behavior. Subject Classification: [43]65.75; [43]70.30. [ABSTRACT FROM AUTHOR]

Factors which determine the discriminability of tonal sequences, or patterns, were investigated in five experiments. The patterns were generally sequences of ten 40-msec tonal components, which ranged in frequency from 256 to 900 Hz, or from 500 to 1500 Hz, in equi-log intervals. Highly trained (15 to 60 h of training prior to collecting experimental data) listeners' abilities to detect changes in the frequency of single tonal components in these patterns were measured using a same-different psychophysical method. The just-detectable values of Δf (d′=1.0) were only slightly larger than for single 40-msec tones presented in isolation for tonal components at the end of the temporal sequences (a ''recency'' effect). Performance was systematically worse for earlier components, the just-detectable Δf increasing by four to five times from the end of the pattern to the beginning (no ''primacy'' effect). The ''recency'' effect was interpreted as a matter of later arriving components interfering with frequency resolution for earlier ones, since a brief silent period (80 to 120 msec) following an early component led to as precise discrimination for that early component as for the last one in the sequence. The higher-frequency components in a given pattern were resolved much more accurately than the lower-frequency components for patterns with overall bandwidths of 250 to 900 Hz and also when the bandwidths were raised from 500 to 1500 Hz. Subject Classification: 65.22, 65.75, 65.64. [ABSTRACT FROM AUTHOR]

Current theories of aging suggest that at least part of the decline in performance on psychophysical tasks, commonly observed in older subjects, may be the result of their becoming more cautious about sensory decisions. This conclusion has been supported by experiments in which the criterion index, β, from signal detection theory is shown to be higher (indicating a strict criterion) for older subjects. A weight-discrimination experiment is reported which failed to replicate the earlier results; older subjects' criteria were the same or more lax than those of younger controls on that task. The possibility that extreme caution on the part of older people may be specific to certain classes of task is discussed. [ABSTRACT FROM PUBLISHER]

While CAR-T therapy is a growing and promising area of cancer research, it is limited by high cost and the difficulty of consistently culturing T-cells to therapeutically relevant concentrations ex-vivo. Cytokines IL-2, IL-7 and IL-15 have been found to stimulate the growth of T cells, however, the optimized combination of these three cytokines for T cell proliferation is unknown. In this study, we designed an integrated experimental and modeling approach to optimize cytokine supplementation for rapid expansion in clinical applications. We assessed the growth data for statistical improvements over no cytokine supplementation and used a systems biology approach to identify genes with the highest magnitude of expression change from control at several time points. Further, we developed a predictive mathematical model to project the growth rate for various cytokine combinations, and investigate genes and reactions regulated by cytokines in activated CD4+ T cells. The most favorable conditions from the T cell growth study and from the predictive model align to include the full range of IL-2 and IL-7 studied, and at lower levels of IL-15 (6 ng/mL or 36 ng/mL). The highest growth rates were observed where either IL-2 or IL-7 was at the highest concentration tested (15 ng/mL for IL-2 and 80 ng/mL for IL-7) while the other was at the lowest (1 ng/mL for IL-2 and 6 ng/mL for IL-7), or where both IL-2 and IL-7 concentrations are moderate-corresponding to condition keys 200, 020, and 110 respectively. This suggests a synergistic interaction of IL-2 and IL-7 with regards to promoting optimal proliferation and survival of the activated CD4+ T cells. Transcriptomic data analysis identified the genes and transcriptional regulators up/down-regulated by each of the cytokines IL-2, IL-7, and IL-15. It was found that the genes with persistent expressing changes were associated with major pathways involved in cell growth and proliferation. In addition to influencing T cell metabolism, the three cytokines were found to regulate specific genes involved in TCR, JAK/STAT, MAPK, AKT and PI3K-AKT signaling. The developed Fuzzy model that can predict the growth rate of activated CD4+ T cells for various combinations of cytokines, along with identified optimal cytokine cocktails and important genes found in transcriptomic data, can pave the way for optimizing activated CD4 T cells by regulating cytokines in the clinical setting. [ABSTRACT FROM AUTHOR]

The article presents the author's comments on the article "Population Size, Military Power, and Antinatal Policy," by Gerry E. Hendershot. In his attempt to construct and to test a causal model relating population size, economic development, military power, and population policies, Hendershot has raised some interesting questions in spite of the model's admittedly poor performance. The article suggests some improvements to the population-power link in his model. One of the first difficulties with Hendershot's model is that he never provides a clear definition of the term national power. Within the context of Hendershot's model it seems most appropriate to view power as a characteristic of the relationship of one individual, social unit, or nation to another. While Hendershot's test for a relationship between population size and power is not specified correctly, his conclusion that the two are positively associated is supported by conceptually better data such as historical evidence on relative population sizes and the outcomes of wars.