With a newly derived equation of state (EOS) of dense matter, we construct zero-temperature compact-star models in hydrostatic equilibrium, for central densities.575 ] 1014 g cm~3 is the nuclear saturation density). Based on SkyrmeÏs concept of baryons as solitons (of Ðnite extent) in the meson Ðeld, the new EOS represents a Ñuid of Skyrmions coupled to a dilaton Ðeld (associated with the glueball of quantum chromodynamics) and a vector meson Ðeld (coupled to the baryon number). We Ðnd stable conÐgurations to exist for and they are mostly Ñuid (the o c /o N ¹ 5.0, Skyrmion Ñuid) ; we thus name them "" Skyrmion stars. ÏÏ The outer region of the star (the crust, for densities below the nuclear saturation density) is constructed using the EOS of Baym, Pethick, and Sutherland and accounts on average for 15% of the total mass of the star. Their masses and radii are 0.5 ¹ and 11.0 km ¹ R ¹ 15.3 km, respectively. The new EOS describes a Ñuid of Skyrmions M/M _ ¹ 2.95 with a unique behavior at high densities. The Skyrmions shrink as the density increases, allowing for a high compression of matter near the core of the star and thus greater gravitational binding energy. The heaviest stars, which can then withstand greater centrifugal forces, are expected to rotate the fastest in our model. Much of this interesting behavior is inherent in the glueball potential, with its negative contribution to the pressure acting to bind the system ; the Skyrmion responds in a nonlinear fashion by shrinking (a result of Skyrmions having structure). Skyrmion stars are fundamentally di †erent from quark stars ; the quark degrees of freedom are integrated out, leaving only meson degrees of freedom. Furthermore, unlike boson/soliton stars where the soliton describes the global structure of the star, Skyrmion stars can be looked at as being made of fermionic soliton objects.

The determinants of fourth, fifth, sixth, seventh, and eighth graders' intentions to perform science learning activities were investigated. Ajzen and Fishbein's theory of reasoned action was used to assess students (n ϭ 254) on their laboratory and nonlaboratory behavioral intentions, which required using the two determinants included in the theory (attitude toward the behavior and subjective norm) as well as five external variables identified by the researcher. The five external variables were gender, grade, race/ ethnicity, socioeconomic status as determined by the range of the family's annual income, and attitude toward science. Two models were tested. The first model included the two determinants as predictor variables and behavioral intention as the criterion. The second model involved the analysis of the two determinants as they were considered in subgroups according to the five external variables. This model also included interaction terms. For laboratory learning activities, the two determinants (attitude toward behavior and subjective norm) were found to contribute collectively to the prediction of behavioral intention, accounting for almost a fourth of the variance. For nonlaboratory learning activities, the two determinants accounted for over a fourth of the variance in behavioral intention. Testing of the second model revealed that for both laboratory and nonlaboratory behavioral intentions, no interaction terms were significant. The results of post hoc tests on significant predictors of behavioral intentions for laboratory and nonlaboratory activities are reported. Implications of this study on future research are also discussed.

Objective To evaluate participation in COVID-19 case investigation and contact tracing in central Washington State between June 15 and July 12, 2020. Methods In this retrospective observational evaluation we combined SARS-CoV-2 RT-PCR and antigen test reports from the Washington Disease Reporting System with community case investigation and contact tracing data for 3 health districts (comprising 5 counties) in central Washington State. All 3 health districts have large Hispanic communities disproportionately affected by COVID-19. Results Investigators attempted to call all referred individuals with COVID-19 (n = 4,987); 71% were interviewed. Of those asked about close contacts (n = 3,572), 68% reported having no close contacts, with similar proportions across ethnicity, sex, and age group. The 968 individuals with COVID-19 who named specific contacts (27% of those asked) reported a total of 2,293 contacts (mean of 2.4 contacts per individual with COVID-19); 85% of listed contacts participated in an interview. Conclusions Most individuals with COVID-19 reported having no close contacts. Increasing community engagement and public messaging, as well as understanding and addressing barriers to participation, are crucial for CICT to contribute meaningfully to controlling the SARS-CoV-2 pandemic.

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