Identifying Forage Quality Eastern Gamagrass [\u3ci\u3eTripsacum dactyloides\u3c/i\u3e (L.) L.] Genotypes from a Wild Regional Collection

Eastern gamagrass is a perennial warm-season grass native to North America and endemic to the eastern United States. The species is highly valuable as both a forage and hay crop. In 2012, 171 wild-type eastern gamagrass accessions were collected from the southeast, mid-Atlantic and Atlantic coast regions. Each accession was relocated to Starkville, MS (33.423585, -88.792394) and established in a long-term nursery. Accessions were analyzed for ploidy level and during 2013-2014 were further evaluated for desirable forage characteristics including: cold tolerance, delayed maturity, rust resistance, and digestibility. Fourteen elite individuals were identified from the original collection and were propagated for further research. Elite genotypes were divided into individual proaxes and transplanted into a RCB design with three replications. Plots measured 3.04 m x 1.21 m with five replicate plants evenly spaced within the plot. Following a one-year establishment period, whole plots were harvested on a 28-day cycle from May to October. Plots were harvested to a 15 cm stubble height with a Wintersteiger Cibus S harvester. Following each harvest, nitrogen fertilizer was applied to all plots at 56 kg N ha-1 using urea ammonium sulfate (32-0-0-12S). Homogenized subsamples were taken to determine percent dry matter, neutral detergent fiber (NDF), acid detergent fiber (ADF), and in-vitro dry matter digestibility (IVDMD). The commercial cultivar ‘Highlander’, was included in the study as a check. Seasonal yields ranged from 1.19 - 2.73 Mg ha-1. Three accessions – originally collected in Alabama and North Carolina – produced significantly greater forage yield than the check (P \u3e 0.0001). Digestibility of the commercial check as well as one accession – collected in Tennessee – were significantly greater than all other accessions (P \u3e 0.0001)

Phenotypic Evaluation of Energycane Varieties for Bioenergy

The need for renewable and carbon-neutral energy is growing as fossil fuel supplies decrease and concerns of climate change increase. C4 grasses are among the most efficient carbon accumulators. Sugarcane (Saccharum officinarum) is a renewable bioenergy crop with low inputs and high yields, but it is limited to tropical and sub-tropical climates. A close relative, Saccharum spontaneum, readily hybridizes with S. officinarum. S. spontaneum lends cold tolerance and higher yields to the hybrid progeny, called energycane. The Sugarcane Breeding Unit (USDA, Houma, Louisiana, USA) selected twenty-six genotypes for testing at Mississippi State University to determine production and cold tolerance at latitude 33.4552° N. Twenty of these genotypes were chosen after the first year for further testing against an energycane check (Ho02-113) and a sugarcane check (L01-299). Seed cane were harvested and planted in the fall of 2019 and 2020 in randomized complete block design with four replications. Plots were 6.1 x 1.8 m, fertilized once at a rate of 168 kg N ha-1. Cane heights and stand counts were collected to monitor genotype growth. At the end of the season, canes were taken for fresh weight, dry weight, °Brix, and sap volume. End of season characteristics of first year growth were: Mean height ranged from 73 to 204 cm; cane number ranged from 9,530 to 68,171 canes ha-1. Plot fresh weights ranged from: 19.9 to 61 Mg ha-1. Mean value of °Brix ranged from 8.9 to 13.7. Mean extractable sap volume ranged from: 2311 to 16,821 L ha-1. Theoretical ethanol yield was calculated for sap and from dry matter. Total theoretical ethanol yield ranged from 939.8 to 3261.2 L ha-1

Cost effectiveness of alternative planned places of birth in woman at low risk of complications: evidence from the Birthplace in England national prospective cohort study

Objectives To estimate the cost effectiveness of alternative planned places of birth

Course-based Science Research Promotes Learning in Diverse Students at Diverse Institutions

Course-based research experiences (CREs) are powerful strategies for spreading learning and improving persistence for all students, both science majors and nonscience majors. Here we address the crucial components of CREs (context, discovery, ownership, iteration, communication, presentation) found across a broad range of such courses at a variety of academic institutions. We also address how the design of a CRE should vary according to the background of student participants; no single CRE format is perfect. We provide a framework for implementing CREs across multiple institutional types and several disciplines throughout the typical four years of undergraduate work, designed to a variety of student backgrounds. Our experiences implementing CREs also provide guidance on overcoming barriers to their implementation

Indoor air quality measurements in energy efficient buildings

The Energy Efficient Buildings Program of the Lawrence Berkeley Laboratory (LBL) has designed and fabricated a mobile laboratory for research and development studies of ventilation requirements and energy utilization in residential and commercial buildings. The Energy Efficient Buildings (EEB) Mobile Laboratory is used in studies of indoor air quality in buildings before and after energy conservation retrofits and in new buildings incorporating energy efficient designs. Indoor air quality measurements have been conducted in residential buildings and work in progress includes indoor air quality monitoring in schools, hospitals, and energy efficient residential buildings. The monitoring program includes measurement of CO, CO/sub 2/, SO/sub 2/, NO, NO/sub 2/, O/sub 3/, infiltration rate (tracer gas technique), and aerosol size distribution on a continuous basis. Total and respirable-fraction particulate samples are collected on membrane filter media for analysis by x-ray fluorescence (XRFA), photoelectron spectroscopy (ESCA), proton activation analysis (PAA), combustion, and wet-chemistry techniques for the determination of particulate elemental composition (S, N, C, etc.) and ionic species such as SO/sub 4//sup 2 -/, NO/sub 3//sup -/, and NH/sub 4//sup +/. Results of the initial phases of this program indicate that the concentrations of some gaseous and respirable particulate air pollutants in specific indoor environments exceed those levels commonly found in the outdoor urban air environment

Use of PDV to measure the overdriven products equation of state in PBX 9502 and PBX 9501 and the EOS in shocked foams

Author Institution: Los Alamos National LaboratorySlides presented at the 2014 Photonic Doppler Velocimetry (PDV) Workshop Hosted by National Security Technologies, LLC, and the University of Nevada Las Vegas, June 24-26, 2014, Las Vegas, Nevada

Effect of Nuclear Quadrupole Interaction on the Relaxation in Amorphous Solids

Recently it has been experimentally demonstrated that certain glasses display an unexpected magnetic field dependence of the dielectric constant. In particular, the echo technique experiments have shown that the echo amplitude depends on the magnetic field. The analysis of these experiments results in the conclusion that the effect seems to be related to the nuclear degrees of freedom of tunneling systems. The interactions of a nuclear quadrupole electrical moment with the crystal field and of a nuclear magnetic moment with magnetic field transform the two-level tunneling systems inherent in amorphous dielectrics into many-level tunneling systems. The fact that these features show up at temperatures $T<100mK$, where the properties of amorphous materials are governed by the long-range $R^{-3}$ interaction between tunneling systems, suggests that this interaction is responsible for the magnetic field dependent relaxation. We have developed a theory of many-body relaxation in an ensemble of interacting many-level tunneling systems and show that the relaxation rate is controlled by the magnetic field. The results obtained correlate with the available experimental data. Our approach strongly supports the idea that the nuclear quadrupole interaction is just the key for understanding the unusual behavior of glasses in a magnetic field.Comment: 18 pages, 9 figure

Rubidium, zirconium, and lithium production in intermediate-mass asymptotic giant branch stars

A recent survey of a large sample of Galactic intermediate-mass (>3 Msun) asymptotic giant branch (AGB) stars shows that they exhibit large overabundances of rubidium (Rb) up to 100--1000 times solar. These observations set constraints on our theoretical notion of the slow neutron capture process (s process) that occurs inside intermediate-mass AGB stars. Lithium (Li) abundances are also reported for these stars. In intermediate-mass AGB stars, Li can be produced by proton captures occuring at the base of the convective envelope. For this reason the observations of Rb, Zr, and Li set complementary constraints on different processes occurring in the same stars. We present predictions for the abundances of Rb, Zr, and Li as computed for the first time simultaneously in intermediate-mass AGB star models and compare them to the current observational constraints. We find that the Rb abundance increases with increasing stellar mass, as is inferred from observations but we are unable to match the highest observed [Rb/Fe] abundances. Inclusion of a partial mixing zone (PMZ) to activate the 13C(a,n)16O reaction as an additional neutron source yields significant enhancements in the Rb abundance. However this leads to Zr abundances that exceed the upper limits of the current observational constraints. If the third dredge-up (TDU) efficiency remains as high during the final stages of AGB evolution as during the earlier stages, we can match the lowest values of the observed Rb abundance range. We predict large variations in the Li abundance, which are observed. Finally, the predicted Rb production increases with decreasing metallicity, in qualitative agreement with observations of Magellanic Cloud AGB stars. However stellar models of Z=0.008 and Z=0.004 intermediate-mass AGB stars do not produce enough Rb to match the observed abundances.Comment: 11 pages, 7 figures, accepted for publication on Astronomy & Astrophysic