Evolution of the atomic and molecular gas content of galaxies in dark matter haloes

We present a semi-empirical model to infer the atomic and molecular hydrogen content of galaxies as a function of halo mass and time. Our model combines the SFR-halo mass-redshift relation (constrained by galaxy abundances) with inverted SFR-surface density relations to infer galaxy H I and H2 masses. We present gas scaling relations, gas fractions, and mass functions from z = 0 to z = 3 and the gas properties of galaxies as a function of their host halo masses. Predictions of our work include: 1) there is a ~ 0.2 dex decrease in the H I mass of galaxies as a function of their stellar mass since z = 1.5, whereas the H2 mass of galaxies decreases by > 1 dex over the same period. 2) galaxy cold gas fractions and H2 fractions decrease with increasing stellar mass and time. Galaxies with M* > 10^10 Msun are dominated by their stellar content at z < 1, whereas less-massive galaxies only reach these gas fractions at z = 0. We find the strongest evolution in relative gas content at z < 1.5. 3) the SFR to gas mass ratio decreases by an order of magnitude from z = 3 to z = 0. This is consistent with lower H2 fractions; these lower fractions in combination with smaller gas reservoirs correspond to decreased present-day galaxy SFRs. 4) an H2-based star- formation relation can simultaneously fuel the evolution of the cosmic star-formation and reproduce the observed weak evolution in the cosmic HI density. 5) galaxies residing in haloes with masses near 10^12 Msun are most efficient at obtaining large gas reservoirs and forming H2 at all redshifts. These two effects lie at the origin of the high star-formation efficiencies in haloes with the same mass.Comment: accepted for publication in MNRAS, 20 pages, 16 figures (+ 1 figure in appendix), data files are accessible through http://www.eso.org/~gpopping/Gergo_Poppings_Homepage/Data.htm

Artificial atmosphere control system

Two-gas control system has been developed which uses existing hardware. Three systems are used for control, monitoring, and safety backup. Pure oxygen will be supplied to maintain safe pressure level should something go wrong

Thermostructural applications of heat pipes

The feasibility of integrating heat pipes in high temperature structure to reduce local hot spot temperature was evaluated for a variety of hypersonic aerospace vehicles. From an initial list of twenty-two potential applications, the single stage to orbit wing leading edge showed the greatest promise and was selected for preliminary design of an integrated heat pipe thermostructural system. The design consisted of a Hastelloy X assembly with sodium heat pipe passages aligned normal to the wing leading edge. A d-shaped heat pipe cross section was determined to be optimum from the standpoint of structural weight

Laboratory Scale Septic Tanks

Author Institution: Metcalf & Eddy, Inc. ; Department of Food, Agricultural, and Biological Engineering, The Ohio State UniversityLaboratory studies of on-site wastewater treatment systems require a dependable supply of septic tank effluent. The goal of this study was to produce a daily supply of septic tank effluent of approximately 140 mg/1 BOD5, 75 mg/1 TSS, and 30 mg/1 NH3-N for use in laboratory studies. The laboratory tank had to be easy to operate, and emulate a septic tank by producing some fluctuation in effluent quality, have the ability to maintain sludge and scum layers, and operate with minimal maintenance. Nine replicates of laboratory septic tanks were developed and tested for twelve weeks. Tanks were constructed from 114 1 cylindrical polyethylene containers with lids, a floating baffle, and discharge pipe. The tanks received a daily mixture of primary sludge, ammonium chloride, and tap water. The resulting septic tank effluent averaged l 6 l mg/1 BOD5, 75 mg/1 TSS, and 25 mg/1 NH3-N

The Role of Occupational Therapy with People Living with Epilepsy: A Scoping Review

Objective: The aim of this scoping review is to systematically examine and organize current literature describing the current roles of occupational therapists with people living with epilepsy, including assessments, interventions, and other behaviors. This will help identify current gaps in the literature to facilitate future research. Methods: Using scoping review methodology, an electronic database search was conducted using the search terms “occupational therapy and epilepsy”. Data was extracted and charted independently by the investigator by way of finding themes and codes through analysis. Results: The total number of studies included was 12. The primary methodology noted were case studies. Per the data, the most common behaviors of OT practitioners when working with individuals living with epilepsy are evaluation and intervention. The assessments and interventions greatly varied due to the vast differences in the way epilepsy presents and affects people, including potential comorbidity involvement. Discussion: The primary limitations of this study include studies only published in English, limited access to literature, and lack of current published literature specifically addressing occupational therapy intervention and epilepsy.https://soar.usa.edu/otdcapstonessummer2021/1011/thumbnail.jp

Paraprofessionals’ Implementation of Constant Time Delay Procedures with Elementary Students with High-Intensity Behavioral Support Needs

Paraprofessionals play a significant role in the education system. However, they often need more training on specific instructional strategies to use with the students they work with. In this study, we trained two paraprofessionals working in a self-contained elementary classroom for students with high-intensity behavioral support needs. Each paraprofessional used constant time delay to support students’ learning to read grade-level sight and science words. Paraprofessionals also gathered maintenance and generalization sessions using individualized social stories created by the classroom teacher. Not only did the four student participants meet mastery of their personalized word sets but paraprofessionals also implemented all phases with high fidelity. We discuss limitations, implications for practice, and recommendations for future research