The Cepheid Impostor HD 18391 and its Anonymous Parent Cluster

New and existing photometry for the G0 Ia supergiant HD 18391 is analyzed in order to confirm the nature of the variablity previously detected in the star, which lies off the hot edge of the Cepheid instability strip. Small-amplitude variability at a level of \Delta V = 0.016+-0.002 is indicated, with a period of P=123.04+-0.06 d. A weaker second signal may be present at P=177.84+-0.18 with \Delta V = 0.007+-0.002, likely corresponding to fundamental mode pulsation if the primary signal represents overtone pulsation (123.04/177.84 = 0.69). The star, with a spectroscopic reddening of E(B-V) = 1.02, is associated with heavily-reddened B-type stars in its immediate vicinity that appear to be outlying members of an anonymous young cluster centered ~10 arcmin to the west and 1661+-73 pc distant. The cluster has nuclear and coronal radii of r_n=3.5 arcmin and R_c=14 arcmin, respectively, while the parameters for HD 18391 derived from membership in the cluster with its outlying B stars are consistent with those implied by its Cepheid-like pulsation, provided that it follows the semi-period-luminosity relation expected of such objects. Its inferred luminosity as a cluster member is M_V=-7.76+-0.10, its age (9+-1)x10^6 years, and its evolutionary mass ~19 M_{\sun}. HD 18391 is not a classical Cepheid, yet it follows the Cepheid period-luminosity relation closely, much like another Cepheid impostor, V810 Cen.Comment: Accepted for Publication (Astronomische Nachrichten

Brazoria County, Texas ; east of the Brazos River : records of wells, drillers' logs, water analyses, and map showing location of wells (1939)

Map of Brazoria County, Texas, Showing Locations of Water Wells. Map of Section of Brazoria County, Texas, Showing Location of Water Wells. "Prepared in cooperation with the United States Department of the Interior, Geological Survey."UT Librarie

Emerging Technologies in Metal Working Fluids and Compatibility with Refrigeration Systems

Metal working fluids (MWF) are basically two types, metal removal (chip making) and metal forming (chip-less). MWF are used in all aspects of production fabrication of refrigeration systems. Metal removal applications typically include turning followed by finish lapping of crankshafts and piston connecting rods, also milling and finish grinding of screw compressor vanes. Metal forming applications include deep drawing of compressor housings, wire drawing, tube forming and stamping of electric motor laminations. MWF are not always completely removed before final assembly. The MWF residuals may get mixed into the refrigerant and compressor lubricant affecting system life and efficiency.  To date, very little compatibility testing of residual MWF in refrigeration lubes and refrigerants has been investigated.  Unlike most lube oils, MWF are typically water-based and traditionally make very high usage of extreme pressure (EP) additives. EP additives help remove metal during the cutting process and actually increase wear. EP containing MWF may interfere with compressor lube oil performance. EP are additives are known to be somewhat acidic and corrosive.  Due environmental persistence concerns, the EPA will restrict the use of chlorinated alkanes as EP additives. Chlorinated alkanes will be being phased out over the next few years and replacements are needed. It has been proven that preformed emulsions are capable of replacing traditional EP additives in MWF. Preformed emulsions allow non-traditional base “oils†to be used in MWF. These non-traditional base oils are generally very high in viscosity and viscosity index. Some of these base stocks exhibit very high film strengths under high pressures encountered in metal removal operations. These high VI and high film strength synthetic base stocks can replace corrosive EP additives without loss of machining or drawing (stamping) performance. Residual films remaining after machining are non-reactive and oil like, providing corrosion protection of in process metal parts prior to assembly. Additionally, high viscosity synthetic base stocks provide low pour points, lower volatility and less vapor interaction within a refrigeration system. Better compatibility with mostly non-polar water insoluble refrigeration lubricants are a benefit. In the future, new refrigerants are likely to be more reactive to reduce environmental persistence. Interactions and effects of various classes MWF with traditional compressor lubes and refrigerants are examined and reported

Toxicity of thermal degradation products of spacecraft materials

Three polymeric materials were evaluated for relative toxicity of their pyrolysis products to rats by inhalation: Y-7683 (LS 200), Y-7684 (Vonar 3 on Fiberglass), and Y-7685 (Vonar 3 on N W Polyester). Criteria employed for assessing relative toxicity were (1) lethality from in-chamber pyrolysis, (2) lethality from an outside-of-chamber pyrolysis MSTL Procedure, and (3) disruption of trained rats' shock-avoidance performance during sub-lethal exposures to in-chamber pyrolysis of the materials

A systematic review of how researchers characterize the school environment in determining its effect on student obesity

BACKGROUND: Obesity in early childhood is a robust predictor of obesity later in life. Schools provide unparalleled access to children and have subsequently become major intervention sites. However, empirical evidence supporting the effectiveness of school-based interventions against childhood obesity is of limited scope and unknown quality. The aim of this systematic review is to critically assess how researchers have characterized the school environment in determining its effect on childhood weight status in order to improve the quality and consistency of research in this area. We conducted a narrative review with a systematic search of the literature in line with PRISMA guidelines (2009). Original peer-reviewed research articles in English were searched from Medline, EMBASE, CENTRAL, CINAHL and PsycINFO databases from earliest record to January 2014. We included empirical research that reported at least one measure of the primary/elementary school environment and its relationship with at least one objective adiposity-related variable for students aged 4-12 years. Two authors independently extracted data on study design, school-level factors, student weight status, type of analysis and effect. RESULTS: Five studies met the inclusion criteria. Each study targeted different parts of the school environment and findings across the studies were not comparable. The instruments used to collect school-level data report no validity or reliability testing. CONCLUSIONS: Our review shows that researchers have used instruments of unknown quality to test if the school environment is a determinant of childhood obesity, which raises broader questions about the impact that schools can play in obesity prevention