Orbital Solutions and Absolute Elements of the Eclipsing Binary MY Cygni

Differential UBV photoelectric photometry for the eclipsing binary MY Cyg is presented. The Wilson-Devinney program is used to simultaneously solve the three light curves together with previously published radial velocities. A comparison is made with the previous solution found with the Russell-Merrill method. We examine the long-term apsidal motion of this well-detached, slightly eccentric system. We determine absolute dimensions, discuss metallicity/Am-star issues, and estimate the evolutionary status of the stars

Prevalence and Severity of Alcohol and Cannabis Use Across the Urban‐Rural Continuum in the Michigan National Guard

PurposeThe National Guard provides critical support both domestically and abroad with soldiers dispersed throughout America and spanning the urban‐rural continuum. To determine if location‐specific interventions may be needed, we compared the prevalence and severity of cannabis and alcohol use among National Guard members across localities.MethodsMichigan National Guard members were enrolled (N = 2,746) during drill weekends as part of a larger randomized behavioral trial. Cannabis (ASSIST; prevalence = 5%) and alcohol use (AUDIT; prevalence = 82%) were compared using hurdle regression models across locality status after adjusting for covariates.FindingsPrevalence of cannabis and alcohol use was predicted by locality (adjusted odds ratio [AOR] = 0.913, 95% CI: 0.838‐0.986, P = .029; AOR = 0.963, 95% CI: 0.929‐0.998, P = .038, respectively), with more use in urban localities. Neither severity of cannabis nor alcohol use was predicted by locality status.ConclusionsPrevalence of cannabis and alcohol use in the National Guard is differentially elevated across localities with higher prevalence in more central, densely populated areas. Findings may inform future work considering accessibility and utilization of prevention and treatment services for Guard members across the urban‐rural continuum.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154619/1/jrh12412.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154619/2/jrh12412_am.pd

A Silicon-Bridged Bis(substituted Cp) Yttrium Complex

rac-Bis(tetrahydrofuran)lithium [bis(2-trimethylsilyl-4-tert-butyl-η^5-cyclopentadienyl)dimethylsilane] dichloroyttrate, [Li(C_4H_80)_2][Y(C_(26)H_(48)-Si_3)Cl_2], M_r= 755.87, triclinic, Pl, ɑ = 13.110 (8), b = 17.163 (15), c = 20.623 (14) Å, ɑ= 104.02 (7), β = 99.38 (5), y = 100.24 (6)º, V = 4326 (6) Å^3, z = 4, D_x = 1.16 g cm^(-3), λ(Mo Kɑ)= 0.71073 Å, μ = 15.86 cm^(-1), F(000) = 1608, room temperature, R = 0.056 for 6136 reflections with F_o^2 > 3σ(F_o^2). There are two virtually identical molecules in the asymmetric unit. In each, the Y atom is tetrahedrally coordinated to a substituted Si-bridged bis(cyclopentadienyl) ligand and to two Cl ions in the cleft. The Li atom is 2.35 Å from each Cl ion, and two molecules of tetrahydrofuran are connected to the Li, completing its tetrahedral coordination

Constraints on the neutron star equation of state from AT2017gfo using radiative transfer simulations

The detection of the binary neutron star GW170817 together with the observation of electromagnetic counterparts across the entire spectrum inaugurated a new era of multi-messenger astronomy. In this study we incorporate wavelength-dependent opacities and emissivities calculated from atomic-structure data enabling us to model both the measured lightcurves and spectra of the electromagnetic transient AT2017gfo. Best-fits of the observational data are obtained by Gaussian Process Regression, which allows us to present posterior samples for the kilonova and source properties connected to GW170817. Incorporating constraints obtained from the gravitational wave signal obtained by the LIGO-Virgo Scientific Collaboration, we present a $90\%$ upper bound on the mass ratio $q \lesssim 1.38$ and a lower bound on the tidal deformability of $\tilde{\Lambda} \gtrsim 197$, which rules out sufficiently soft equations of state. Our analysis is a path-finder for more realistic kilonova models and shows how the combination of gravitational wave and electromagnetic measurements allow for stringent constraints on the source parameters and the supranuclear equation of state

Serologic and Molecular Detection of Granulocytic Ethrlichiosis in Rhode Island

A new indirect fluorescent-antibody (IFA) assay with antigen produced in vitro in the human promyelocytic leukemia cell line HL60 was used to identify the first recognized case of human granulocytic ehrlichiosis in Rhode Island. This IFA assay was used to detect granulocytic ehrlichiae in white-footed mice and in a dog inhabiting the area surrounding the patient’s residence. Host-seeking Ixodes scapularis ticks found in the same habitat also were infected. I. scapularis ticks collected from other locations were fed on dogs and New Zealand White rabbits to assess the competency of these species as hosts of granulocytotropic Ehrlichia. Tick-induced infections of dogs were confirmed by serologic testing, tissue culture isolation, and PCR amplification, whereas several rabbits seroconverted but were PCR and culture negative. PCR amplification of the 16S rRNA gene and DNA sequencing of the PCR products or culture isolation was used to confirm granulocytic Ehrlichia infections in humans, dogs, white-footed mice, and ticks

A Silicon-Bridged Bis(substituted Cp) Yttrium Complex

rac-Bis(tetrahydrofuran)lithium [bis(2-trimethylsilyl-4-tert-butyl-η^5-cyclopentadienyl)dimethylsilane] dichloroyttrate, [Li(C_4H_80)_2][Y(C_(26)H_(48)-Si_3)Cl_2], M_r= 755.87, triclinic, Pl, ɑ = 13.110 (8), b = 17.163 (15), c = 20.623 (14) Å, ɑ= 104.02 (7), β = 99.38 (5), y = 100.24 (6)º, V = 4326 (6) Å^3, z = 4, D_x = 1.16 g cm^(-3), λ(Mo Kɑ)= 0.71073 Å, μ = 15.86 cm^(-1), F(000) = 1608, room temperature, R = 0.056 for 6136 reflections with F_o^2 > 3σ(F_o^2). There are two virtually identical molecules in the asymmetric unit. In each, the Y atom is tetrahedrally coordinated to a substituted Si-bridged bis(cyclopentadienyl) ligand and to two Cl ions in the cleft. The Li atom is 2.35 Å from each Cl ion, and two molecules of tetrahydrofuran are connected to the Li, completing its tetrahedral coordination

Constraints on the neutron star equation of state from AT2017gfo using radiative transfer simulations

The detection of the binary neutron star merger GW170817 together with the observation of electromagnetic counterparts across the entire spectrum inaugurated a new era of multimessenger astronomy. In this study, we incorporate wavelength-dependent opacities and emissivities calculated from atomic-structure data enabling us to model both the measured light curves and spectra of the electromagnetic transient AT2017gfo. Best fits of the observational data are obtained by Gaussian Process Regression, which allows us to present posterior samples for the kilonova and source properties connected to GW170817. Incorporating constraints obtained from the gravitational wave signal measured by the LIGO-Virgo Scientific Collaboration, we present a 90 per cent upper bound on the mass ratio q ≲ 1.38 and a lower bound on the tidal deformability of Λ ≳ 197, which rules out sufficiently soft equations of state. Our analysis is a path-finder for more realistic kilonova models and shows how the combination of gravitational wave and electromagnetic measurements allow for stringent constraints on the source parameters and the supranuclear equation of state

Cataclysmic Variables in the First Year of the Zwicky Transient Facility

Using selection criteria based on amplitude, time, and color, we have identified 329 objects as known or candidate cataclysmic variables (CVs) during the first year of testing and operation of the Zwicky Transient Facility. Of these, 90 are previously confirmed CVs, 218 are strong candidates based on the shape and color of their light curves obtained during 3–562 days of observation, and the remaining 21 are possible CVs but with too few data points to be listed as good candidates. Almost half of the strong candidates are within 10 deg of the galactic plane, in contrast to most other large surveys that have avoided crowded fields. The available Gaia parallaxes are consistent with sampling the low mass transfer CVs, as predicted by population models. Our follow-up spectra have confirmed Balmer/helium emission lines in 27 objects, with four showing high-excitation He ii emission, including candidates for an AM CVn, a polar, and an intermediate polar. Our results demonstrate that a complete survey of the Galactic plane is needed to accomplish an accurate determination of the number of CVs existing in the Milky Way