Measurement of Non-Photonic Electron Angular Correlations with Charged Hadrons

Correlations of non-photonic electrons with charged hadrons are studied using the PYTHIA Monte Carlo event generator in p+p collisions at $\sqrt{s_{NN}} = 200$ GeV. We propose experimental methods to estimate the relative contributions to non-photonic electrons from charm and bottom decays. We present the measurement of azimuthal correlations between non-photonic electrons and charged hadrons in p+p collisions at $\sqrt{s_{NN}} = 200$ GeV from STAR. The results are compared to PYTHIA simulations to estimate the relative contributions of $D$ and $B$ meson semi-leptonic decays to non-photonic electrons. Our preliminary result indicates that at $p_{T} \sim 4.0 - 6.0$ GeV/c the measured $B$ contribution to non-photonic electrons is comparable to $D$ contribution, and is consistent with the FONLL calculation.Comment: 8 pages, 7 figures. Proceedings for XIth International Workshop on Correlation and Fluctuation in Multiparticle Production, Nov. 21-24, Hangzhou, China. To appear in International Journal of Modern Physics

An Experimental Study on Societal Factors Affecting VOT of English Plosives

Plosives are integral components of English consonants. In phonetics, English plosives are classified into voiceless plosives /p, t, k/ and /b, d, g/. VOT (voice onset time) was defined as “the time interval between the burst that marks release of the stop closure and the onset of quasi-periodicity that reflects laryngeal vibration”. VOT is a significant acoustic feature and analytic parameter of plosives. Referring to Labov’s experimental model of linguistic variation analysis, this study investigates the influences of societal factors have on the VOT of English plosives.In this study, 15 English words with word-initial voiceless plosives /p, t, k/ and 15 word-initial voiced plosives /b, d, g/ were selected as reading material; meanwhile, 30 subjects were randomly recruited to read, and audio samples were collected. It is found that the two social factors (gender and regional dialect) selected in this experiment have influences in different degrees on the English plosive VOT of the subjects. The specific results are as follows.For gender, no significant difference exists between males and females, but the mean VOT of females is longer than that of males, which is basically consistent with previous research results. The underlying reasons of the gender VOT differences inferred by this paper can be physiological and sociophonetical. For regional dialects, the VOT of the subjects were primarily influenced by Southwest Mandarin and Min Dialect, in which the mean value of voiceless plosives was higher and the difference was greater for speakers of Southwest Mandarin, and the mean value of voiced plosives was higher and the difference was greater for speakers of Min Dialect. The results of this empirical study theoretically provide some reference for acoustic researches, and pedagogically, provide some implications for optimizations of English curriculums in university

Is Congestion Pricing Effective for Traffic Jams?

The complexity of urban congestion requires policy-makers to adopt different congestion control measures that suit the characteristics of the city at the proper time. The paper focuses on the most controversial congestion pricing and offers methods to judge the efficacy of the policy by game theoretic approaches. It is found that congestion pricing is not merely a Pigouvian tax that internalizes drivers’ externalities, but also a powerful means to enhance public traffic proportion and balance road utilization on the premise of maximized social util-ity. Meanwhile, the embedded multiple case study shows that theoretical correctness of the policy is a necessary, but not sufficient condition for its effectiveness because the valid operation of the policy further requires cities to hold certain attributes in some aspects, such as econom-ic level, population density, proper pricing mechanism, and the ability to limit access to and from certain areas. Moreover, the authority should pay attention to matching the policy goal and its functions for successful implementation

Trends in the prevalence of social isolation among middle and older adults in China from 2011 to 2018: the China Health and Retirement Longitudinal Study

Background: Epidemiological studies have shown that social isolation, which is prevalent in older adults, is associated with a range of adverse health outcomes, but the prevalence of and trends in regard to social isolation remain ambiguous in China. The aim of this study was to elucidate the trends regarding the prevalence of social isolation among middle-aged and older adults in China from 2011 to 2018 and to further identify associated risk factors. Methods: A repeated cross-sectional study, The data were derived from panel sample data of four waves conducted from May 2011 to August 2018 in the nationally representative China Health and Retirement Longitudinal Study (CHARLS) using multistage probability sampling. Social isolation was ascertained by the five item Steptoe Social Isolation Index. The potential covariates were demographic characteristics, lifestyle factors, and health status. Linear-by-linear association was used to assess the trends in regard to social isolation over time under the influence of the potential covariates. Linear-by-linear association and an age-period-cohort analysis were used to explore the trends, and two-level (time, individual) generalized estimating equation models (GEE) linked multivariate binary logistic regression were performed to identify risk factors. Results: A high prevalence of social isolation and a moderate upward trend from 2013 to 2018 were observed among a U-shaped trend prevalence of social isolation from 2011 to 2018 across China, with rates of 38.09% (95% CI = 36.73–39.45) in 2011, 33.66% (32.32–35.00) in 2013, 39.13% (37.59–40.67) in 2015, and 39.95% (38.59–41.31) in 2018 (p < 0.001). The prevalence of social isolation increased with age and educational attainment. Females had a higher prevalence than males. The prevalence of social isolation was found to be significantly lower in pensioners than in non-pensioners between 2011 and 2018 (p < 0.001). The prevalence of social isolation was 38.9%, 34.9%, 38.5%, and 44.08% about three times higher among those who doid not use the Internet and 13.44%, 11.64%, 12.93%, and 16.73% than among those who doid in 2011, 2013, 2015 and 2018 respectively. The participants with short (0–5 h) and long sleep (9 or more hours), and poor self-rated health had a higher prevalence of social isolation than the others. Older age, lower educational attainment, living in a rural region, lack of medical insurance or pension, lack of internet use and poor health were risk factors (p < 0.05). Conclusions: We found a U-shaped prevalence of social isolation trends from 2011 to 2018 and revealed increasing trends from 2013 to 2018 among middle-aged and older adults in China. The findings of the study highlight the urgent need for interventions to reduce social isolation including improving sleep quality and internet skills. Disadvantaged groups in terms of age, economic status, and health status should be the focus of such interventions, especially in the era of COVID-19