Search NASA⌕ Search

SEARCH · Search NASA

Results for “Yield”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Bacterial community dynamics as a result of growth-yield trade-off and multispecies metabolic interactions toward understanding the gut biofilm niche

Abstract Bacterial communities are ubiquitous, found in natural ecosystems, such as soil, and within living organisms, like the human microbiome. The dynamics of these communities in diverse environments depend on factors such as spatial features of the microbial niche, biochemical kinetics, and interactions among bacteria. Moreover, in many systems, bacterial communities are influenced by multiple physical mechanisms, such as mass transport and detachment forces. One example is gut mucosal communities, where dense, closely packed communities develop under the concurrent influence of nutrient transport from the lumen and fluid-mediated detachment of bacteria. In this study, we model a mucosal niche through a coupled agent-based and finite-volume modeling approach. This methodology enables us to model bacterial interactions affected by nutrient release from various sources while adjusting individual bacterial kinetics. We explored how the dispersion and abundance of bacteria are influenced by biochemical kinetics in different types of metabolic interactions, with a particular focus on the trade-off between growth rate and yield. Our findings demonstrate that in competitive scenarios, higher growth rates result in a larger share of the niche space. In contrast, growth yield plays a critical role in neutralism, commensalism, and mutualism interactions. When bacteria are introduced sequentially, they cause distinct spatiotemporal effects, such as deeper niche colonization in commensalism and mutualism scenarios driven by species intermixing effects, which are enhanced by high growth yields. Moreover, sub-ecosystem interactions dictate the dynamics of three-species communities, sometimes yielding unexpected outcomes. Competitive, fast-growing bacteria demonstrate robust colonization abilities, yet they face challenges in displacing established mutualistic systems. Bacteria that develop a cooperative relationship with existing species typically obtain niche residence, regardless of their growth rates, although higher growth yields significantly enhance their abundance. Our results underscore the importance of bacterial niche dynamics in shaping community properties and succession, highlighting a new approach to manipulating microbial systems.

Microbiology↗
DOE OSTI2017

Gene and transcript abundances of bacterial type III secretion systems from the rumen microbiome are correlated with methane yield in sheep

Background: Ruminants are important contributors to global methane emissions via microbial fermentation in their reticulo-rumens. This study is part of a larger program, characterising the rumen microbiomes of sheep which vary naturally in methane yield (g CH4/kg DM/day) and aims to defne diferences in microbial communities, and in gene and transcript abundances that can explain the animal methane phenotype. Methods: Rumen microbiome metagenomic and metatranscriptomic data were analysed by Gene Set Enrichment, sparse partial least squares regression and the Wilcoxon Rank Sum test to estimate correlations between specifc KEGG bacterial pathways/genes and high methane yield in sheep. KEGG genes enriched in high methane yield sheep were reassembled from raw reads and existing contigs and analysed by MEGAN to predict their phylogenetic origin. Protein coding sequences from Succinivibrio dextrinosolvens strains were analysed using Efective DB to predict bacterial type III secreted proteins. The efect of S. dextrinosolvens strain H5 growth on methane formation by rumen methanogens was explored using co-cultures. Results: Detailed analysis of the rumen microbiomes of high methane yield sheep shows that gene and transcript abundances of bacterial type III secretion system genes are positively correlated with methane yield in sheep. Most of the bacterial type III secretion system genes could not be assigned to a particular bacterial group, but several genes were afliated with the genus Succinivibrio, and searches of bacterial genome sequences found that strains of S. dextrinosolvens were part of a small group of rumen bacteria that encode this type of secretion system. In co-culture experiments, S. dextrinosolvens strain H5 showed a growth-enhancing efect on a methanogen belonging to the order Methanomassiliicoccales, and inhibition of a representative of the Methanobrevibacter gottschalkii clade. Conclusions: This is the frst report of bacterial type III secretion system genes being associated with high methane emissions in ruminants, and identifes these secretions systems as potential new targets for methane mitigation research. The effects of S. dextrinosolvens on the growth of rumen methanogens in co-cultures indicate that bacteriamethanogen interactions are important modulators of methane production in ruminant animals.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2016

Rumen metagenome and metatranscriptome analyses of low methane yield sheep reveals a Sharpea -enriched microbiome characterised by lactic acid formation and utilisation

Enteric fermentation by farmed ruminant animals is a major source of methane and constitutes the second largest anthropogenic contributor to global warming. Reducing methane emissions from ruminants is needed to ensure sustainable animal production in the future. Methane yield varies naturally in sheep and is a heritable trait that can be used to select animals that yield less methane per unit of feed eaten. We previously demonstrated elevated expression of hydrogenotrophic methanogenesis pathway genes of methanogenic archaea in the rumens of high methane yield (HMY) sheep compared to their low methane yield (LMY) counterparts. Methane production in the rumen is strongly connected to microbial hydrogen production through fermentation processes. In this study, we investigate the contribution that rumen bacteria make to methane yield phenotypes in sheep. Using deep sequence metagenome and metatranscriptome datasets in combination with 16S rRNA gene amplicon sequencing from HMY and LMY sheep, we show enrichment of lactate-producing Sharpea spp. in LMY sheep bacterial communities. Increased gene and transcript abundances for sugar import and utilisation and production of lactate, propionate and butyrate were also observed in LMY animals. Sharpea azabuensis and Megasphaera spp. act as important drivers of lactate production and utilisation according to phylogenetic analysis and read mappings. Our findings show that the rumen microbiome in LMY animals supports a rapid heterofermentative growth, leading to lactate production. We postulate that lactate is subsequently metabolised mainly to butyrate in LMY animals, producing 2 mol of hydrogen and 0.5 mol of methane per mol hexose, which represents 24 % less than the 0.66 mol of methane formed from the 2.66 mol of hydrogen produced if hexose fermentation was directly to acetate and butyrate. These findings are consistent with the theory that a smaller rumen size with a higher turnover rate, where rapid heterofermentative growth would be an advantage, results in lower hydrogen production and lower methane formation. Together with previous methanogen gene expression data, this builds a strong concept of how animal traits and microbial communities shape the methane phenotype in sheep.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2025

Data for Soil Fertility Management for Sustainable Miscanthus × giganteus Production: Increased Tiller Weight from Nitrogen Management Explains Yield Gains in Aged Miscanthus

Aging-related yield decline in Miscanthus × giganteus (miscanthus) remains a major constraint to sustainable biomass production. This study evaluated how nitrogen (N) management and soil fertility influence yield-component traits and productivity in aging miscanthus. Trials were conducted at two sites established in 2008 at the University of Illinois Energy Farm, Urbana, IL. (i) The Sun Grant trial received 0, 60, and 120 kg N ha−1 annually until 2015. Starting 2021, half of each plot received 60 or 120 kg N ha−1, resulting in six legacy-contemporary treatments: 0N–0N, 0N–120N, 60N–0N, 60N–60N, 120N–0N, 120N–120N. (ii) The Energy Farm trial remained unfertilized until 2014, when one half of each plot received 56 kg N ha−1, forming two treatments: 0N–0N, 0N–56N. Sun Grant trial results showed N fertilization increased tiller density (tillers m−2) and tiller weight (g tiller−1) in juvenile to early-mature miscanthus (2011–2015). After N withdrawal, both traits declined (20 % and 40 %), though legacy effects persisted in tiller weight in the aging stands (2020–2023). Contemporary N had little effect on tiller density but increased tiller weight by 34 %–77 %, resulting in 23 %–106 % higher machine-harvested biomass yield in 0–120N, 60-60N, and 120-120N plots. At the Energy Farm trial, 0N–56N plots yielded 59 %–108 % more biomass than 0N–0N. Soil total N increased (Sun Grant: 47 % by 2020; Energy Farm: 58 % by 2023), while Mehlich-3 P (42 %–44 %) and K (21 %–46 %) declined. These findings identify tiller weight as a key determinant of biomass yield in aging miscanthus and highlight the need for P and K management for long-term productivity.

miscanthus↗
DOE OSTI2021

Data from Genotype-Environment-Management Interactions in Biomass Yield and Feedstock Composition of Photoperiod-Sensitive Energy Sorghum

Recently introduced photoperiod-sensitive (PS) biomass sorghum ( Sorghum bicolor L. Moench) needs to be investigated for yield potential under different cultivation environments with reasonable nitrogen (N) inputs. The objectives of this study were to (1) evaluate the biomass yield and feedstock quality of four sorghum hybrids with different levels of PS ranging from very PS (VPS) hybrids and to moderate PS (MPS) hybrids, and (2) determine the optimal N inputs (0~168 kg N ha−1) under four environments: combinations of both temperate (Urbana, IL) and subtropical (College Station, TX) regions during 2018 and 2019. Compared to TX, the PS sorghums in central IL showed higher yield potential and steady feedstock production with an extended day length and with less precipitation variability, especially for the VPS hybrids. The mean dry matter (DM) yields of VPS hybrids were 20.5 Mg DM ha−1 and 17.7 Mg DM ha−1 in IL and TX, respectively. The highest N use efficiency occurred at a low N rate of 56 kg N ha−1 by improving approximately 33 kg DM ha−1 per 1.0 kg N ha−1 input. Approximately 70% of the PS sorghum biomass can be utilized for biofuel production, consisting of 58-65% of the cell-wall components and 4-11% of the soluble sugar. This study demonstrated that the rainfed temperate area (e.g., IL) has a great potential for the sustainable cultivation of PS energy sorghum due to their observed high yield potential, stable production, and low N requirements.

Biomass Analytics↗
DOE OSTI2018

Total yield of reactive species originating from an atmospheric pressure plasma jet in real time

Abstract It is now well established that plasma-induced reactive species are key agents involved in many biochemical reactions. This work reports on the formation of plasma reactive species in an acidified ferrous sulfate (Fricke) solution interacting with an atmospheric pressure plasma jet (APPJ). A yield of ferric (Fe 3+ ) ions measured using in situ absorption spectroscopy was attributed to the formation of plasma reactive species provided and/or originated in the solution. The results indicated that the number of reactive species formed was proportional to plasma frequency and voltage. However, the Fe 3+ yield per pulse decreased with increased frequency. To obtain a better understanding of the processes and species involved in the chemical reactions due to plasma exposure, Fe 3+ yields were calculated and compared to the experimental data. At higher frequencies, there was insufficient time to complete all the reactions before the next pulse reached the solution; at lower frequencies, the Fe 3+ yield was higher because of the relatively longer time available for reactions to occur. In addition, the comparison between DNA damage levels and Fe 3+ yields was investigated under different experimental conditions in order to verify the usefulness of both the Fricke solution and the DNA molecule as a probe to characterize APPJs.

Biochemistry & Molecular Biology↗
DOE OSTI2019

Miscanthus x giganteus yield in a REpeated PLAnting Year (REPLAY) experiment across three sites in Iowa, USA.

Research objectives were to study nitrogen (N) fertilization and age effect on Miscanthus x giganteus (mxg) yield and their interaction. In addition, we studied how establishment conditions affected mxg yield response to N fertilization. This is the first repeated planting year experiment conducted on perennial bioenergy grasses. Data showed that mxg yield response to N fertilization was highly variable. Establishment effects were an important driver of this variability and caused significant changes on the magnitude and direction of one-year-old stands’ response to N fertilization. With repeated planting we compared yield gain from first to second year of growth of different single starts. Yield gain of each single start was different within and between sites. This site-specific response suggests that important biases could be introduced when comparing results across studies if repeated planting is not utilized. Biomass from mxg plots was sampled annually in winter or early spring after multiple days with freezing temperatures (Table 1). At each harvest, two 1-m2 quadrats per plot were collected by hand at 0.10 m above the soil surface and weighed. In 2016 and 2018, we used a composite subsample to estimate dry matter content. In 2017, the dry weight subsamples were made of 15 randomly collected stems from each plot. Subsamples were weighed in the field and dried to constant mass at 60 °C in a forced air drier. The final mass was recorded and dry matter content was calculated for each plot.

Agricultural Science↗
DOE OSTI2025

Source Characterization at Low Yields from Physics Experiment One A

The detonation of a well-recorded coupled explosion at the well-characterized Nevada National Security Site, as part of Physics Experiment One, has provided us with an opportunity to compare and contrast methods and results of yield estimation and other event characterization methods. Yield estimates are made using several methods, including local/regional magnitudes, waveform envelopes, acoustic amplitudes, joint seismoacoustic yield, and moment tensors. We include in our analysis a discussion and comparison of applicability, calibrations, assumptions, and uncertainties involved in each. With the exception of magnitude-based methods, all the techniques were more or less successful in recovering the known yield. It is, however, useful to be cognizant of requirements and calibrations, such as station coverage, emplacement conditions, propagation characterization, and uncertainties, to apply the methods to other areas with less complete information. We demonstrate that we can be successful at monitoring low-yield explosions using a variety of methods assuming that the signal-to-noise ratio is adequate at recording stations, and that the material properties are taken into account. Depth estimates are also important, particularly if one allows the possibility of a surface explosion.

Pasyanos, Michael E. [Lawrence Livermore National ↗
DOE OSTI2022

Estimating Explosion Yields Using Moment Tensor Solutions and Seismic Moment

We report seismic moment, a measurable and well-understood quantity of seismic sources, is used to estimate the yield of explosions. Application of such a method in the past, as in the manner of m b -derived yields, has been complicated by the effect of variations in the explosion working point, depth, and secondary source effects (such as spalling and tectonic release) on the observed moment. We start using the full (six-element) moment tensor solution, which can capture the relevant source physics and, at least in theory, better isolate the primary explosion source. The moment-to-yield ratio is then estimated using an explosion source model which, provided with emplacement conditions, can relate the two parameters. We discuss the major sources of uncertainty associated with the method, and calibrate it with chemical and nuclear explosions at the Nevada National Security Site. We then apply the method to published moment tensor solutions for the six declared North Korean nuclear explosions that occurred between 2006 and 2017. The results are mostly consistent with other yield estimates made using a variety of high-frequency methods. This technique is a new approach to estimating explosive yield and simple to implement, as much of the complexity is captured by the source models.

58 GEOSCIENCES↗
DOE OSTI2017

Camelina Seed Yield and Fatty Acids as Influenced by Genotype and Environment

Camelina (Camelina sativa L. Crantz) is an alternative oilseed crop with potential for fallow replacement in dryland cereal-based crop production systems in the semiarid Great Plains. The interaction between genotype and environment was investigated on camelina seed yield, oil content, and fatty acid composition across two locations in the U.S. Great Plains. Treatments were three spring camelina genotypes (cultivars Blaine Creek, Pronghorn, and Shoshone), three growing seasons (2013, 2014, and 2015) and two locations (at Hays, KS, and Moccasin, MT). Our results showed camelina grown at Hays yielded 54% less than that at Moccasin. Blaine Creek yielded 17 and 42% more than Pronghorn and Shoshone at Hays but yields were not different among genotypes at Moccasin. Oil content ranged from 262 g kg -1 at Hays to 359 g kg -1 at Moccasin. The proportion of polyunsaturated fatty acids (PUFAs) ranged from 51% at Hays to 55% at Moccasin, whereas monounsaturated fatty acid (MUFA) and saturated fatty acid (SFA) contents were greater at Hays. The linolenic acid content ranged from 26% when Pronghorn was planted at Hays to 35% when planted at Moccasin. In general, the variations in seed yield and fatty acid profile corresponded well with growing season precipitation and temperatures at each environment.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2019

Optimization of SiV Defect Yield in Diamond Substrates

Color centers (defect complexes such as SiV) in diamond have shown potential in fields ranging from metrology, cybersecurity to quantum computation. Demonstrations in these fields have pushed the envelope of state-of-the-art operations – for example, single photon sources (SPS) making use of SiV centers in diamond for quantum key distribution have demonstrated all the requirements for SPS operation including: (1) stable operation with second correlation function <<1, (2) electrically driven single photon emission and (3) compatibility with frequenc y conversion to telecommunication frequencies. To-date, however, all these demonstrations have been on lab-scale one-off devices. The key question behind how to deterministically fabricate these devices, namely activation yield has been overlooked. For context, Si based semiconductor devices are hugely successful because we have a high activation yield for implanted dopants. This is not yet true for diamond color centers. As currently understood, the color center yield is dominated by a lack of vacancies in the immediate area of the implantation. We propose to optimize the activation yield of color center using a combination of (1) focused single ion implantation with in-situ detection to count the number of implanted Si ions and (2) localized point defect (vacancy) creation using a focused Li ion beam to improve the yield. These experiments build on the unique capabilities of the SNL nanoImplanter (nI) to produce focused ion beam with spatial resolution of < 10 nm of both Si and Li ions. This work will also leverage our world-leading single ion implantation and detection capabilities.

36 MATERIALS SCIENCE↗
DOE OSTI2020

New Yield Estimates for Nuclear Detonations Over Water

One of the primary methods used by the United States to estimate the yields of atmospheric nuclear tests performed in the 1940’s, 50’s, and 60’s was to film each detonation with a high-speed camera, measure the blast radius as a function of time, and then use Taylor’s spherical blast wave equation to calculate the source energy (i.e., the yield). For surface detonations, the yield in Taylor’s equation was assumed to be twice as large as the actual yield to account for the energy reflected from the surface, assuming the ground was a perfect reflector. Recent simulations of surface detonations over water (referred to as barge shots) have shown that Taylor’s equation must be modified further to account for material entrainment and heat losses. We have computed this lost energy using a high-order radiation-hydrodynamics code to determine the reduction in blast radius vs. time. By analyzing simulation data in the same manner as film data, we have determined that a yield correction factor of 1.27± 0.04 should be applied to the barge shots.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2024

Energy Dependent Fission Product Yields (2nd year Milestone and Deliverables)

Introduction to the project: One of the Laboratory missions is to provide consistent, high-precision fission product; yield data critical for testing fission models and maintaining the safety and security of the nation’s nuclear weapons stockpile. However, high-quality, energy-differential fission product yield data is missing for certain actinides and neutron energies important to constrain the new U.S. Nuclear Data Program evaluation effort; It has been shown that the reactor antineutrino anomaly may be at least partially caused by roughly 20 fission products. The fission product yield data is missing or incomplete for many of these isotopes, thus it is necessary to accurately determine these values to better constrain the anomaly; Aitor Bracho is measuring very short-lived (seconds to minutes) fission product yields of 235 U and 239 Pu using monoenergetic neutron beams at E n = 60 and 560 keV; Aitor Bracho is using a direct approach utilizing a state-of-the-art rabbit transfer system, superior HPGe detector, and digital acquisition systems for fission decay measurements. The goals of this project: lop experimental capabilities and data analysis techniques to carry out the gamma-ray spectra analysis necessary for fission product yield calculation; Provide high-precision and energy-dependent fission product data supporting fission theory, neutrino physics, and applied physics.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2024

Yield requirements for studies of double (n,2n) reactions on dopant material in NIF Capsules

At the National Ignition Facility (NIF) inertial confinement fusion (ICF) ignition has been achieved, involving yields up to about 5 MJ. In addition, it has been suggested that proposed advances at the NIF facility, involving moderate upgrades in laser energy, could further increase fusions gains to yields in the 30-40 MJ range. Such high yield would open the possibility for new studies in many areas of science. In the present analysis, we focus on how these possible future fusion yields would make measurements of multi-step nuclear reactions on dopant material practical. For this, we consider the scenario of loading dopant material into the ablator of cryogenic capsules and estimate yields needed to measure previously inaccessible double (n,2n) reactions under ICF conditions.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

Predicting Field Efficiency of Round-Baling Operations in High-Yielding Biomass Crops

Model simulations for bioenergy harvest planning need to utilize equipment-capacity relationships for equipment operating under the high-yield conditions typical of a biomass crop. These performance assumptions have a direct bearing on the estimates of machine capacity, the number of machines required, and, therefore, the cost to fulfill the biorefinery plant demands for a given harvest window. Typically, two major issues in these models have been poorly understood: the available time required to complete the harvest operation (often called probability of workdays) and the capacity of the harvest equipment as impacted by yield. Simulations use annual yield estimates, which incorporate weather events, to demonstrate year-to-year effects. Some simulations also incorporate potential yield increases from genetically modified energy crops. There are limited field performance data for most current forage equipment used for harvesting high-yield biomass crops. Analysis shows that the impact of wrap/eject time for round balers resulted in a 50% reduction in achieved throughput capacity (Mg/h). After the maximum throughput is reached, the cost of the round bale operation (3.23 USD/Mg) is double that of the large-square baler (1.63 USD/Mg). The round baler achieved throughput capacity is 50% less (32.7 Mg/h compared to 71.0 Mg/h) than the large-square baler.

09 BIOMASS FUELS↗
DOE OSTI2016

Stellar yields from metal-rich asymptotic giant branch models

We present new theoretical stellar yields and surface abundances for three grids of metal-rich asymptotic giant branch (AGB) models. Post-processing nucleosynthesis results are presented for stellar models with initial masses between 1 M {sub ☉} and 7.5 M {sub ☉} for Z = 0.007, and 1 M {sub ☉} and 8 M {sub ☉} for Z = 0.014 (solar) and Z = 0.03. We include stellar surface abundances as a function of thermal pulse on the AGB for elements from C to Bi and for a selection of isotopic ratios for elements up to Fe and Ni (e.g., {sup 12}C/{sup 13}C), which can be obtained from observations of molecules in stars and from the laboratory analysis of meteoritic stardust grains. Ratios of elemental abundances of He/H, C/O, and N/O are also included, which are useful for direct comparison to observations of AGB stars and their progeny, including planetary nebulae. The integrated elemental stellar yields are presented for each model in the grid for hydrogen, helium, and all stable elements from C to Bi. Yields of Li are also included for intermediate-mass models with hot bottom burning. We present the first slow neutron-capture (s-process) yields for super solar metallicity AGB stars with Z = 0.03, and the first complete s-process yields for models more massive than 6 M {sub ☉} at all three metallicities.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2018

Cosmic-Ray Nucleosynthesis of p -nuclei: Yields and Routes

We review the cosmic-ray nucleosynthesis (CRN) of proton-rich stable nuclides (p-nuclides). We calculate the cosmic-ray (CR) energy spectra of heavy nuclides with mass number $A=[74,209]$, taking into account the detailed nuclear spallation, decay, energy loss, and escape from the Galaxy during the CR propagation. We adopt the latest semiempirical formula SPACS for the spallation cross sections and the latest data on nuclear decay. Effective electron-capture decay rates are calculated using the proper cross sections for recombination and ionization in the whole CR energy region. Measured CR spectral shapes vary for different nuclides. Abundances of proton-rich unstable nuclides increase in CRs with increasing energy relative to those of other nuclides. Yields of the primary and secondary spallation processes and differential yields from respective seed nuclides are calculated. We find that the CR energy region of $\leqslant { \mathcal O }(100)$ MeV/nucleon predominantly contributes to the total yields. The atomic cross sections in the low-energy range adopted in this study are then necessary. Effects of CRN on the Galactic chemical evolution of p-nuclides are calculated. Critical seed nuclides are identified for respective p-nuclides. The contribution of CRN is significant for 180m Ta, accounting for about 20% of the solar abundance. About 87% of the 180m Ta CRN yield can be attributed to the primary process. The most important production routes are reactions of 181 Ta, 180 Hf, and 182 W. CRN yields of other p-nuclides are typically about ${ \mathcal O }$(10 –4 –10 –2 ) of solar abundances.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2018

SYGMA: Stellar Yields for Galactic Modeling Applications

The Stellar Yields for Galactic Modeling Applications (SYGMA) code is an open-source module that models the chemical ejecta and feedback of simple stellar populations (SSPs). It is intended for use in hydrodynamical simulations and semi-analytic models of galactic chemical evolution. The module includes the enrichment from asymptotic giant branch (AGB) stars, massive stars, Type Ia supernovae (SNe Ia), and compact binary mergers. An extensive and extendable stellar yields library includes the NuGrid yields with all elements and many isotopes up to Bi. Stellar feedback from mechanic and frequency-dependent radiative luminosities are computed based on NuGrid stellar models and their synthetic spectra. The module further allows for customizable initial mass functions and SN Ia delay-time distributions to calculate time-dependent ejecta based on stellar yield input. A variety of r-process sites can be included. A comparison of SSP ejecta based on NuGrid yields with those from Portinari et al. and Marigo reveals up to factors of 3.5 and 4.8 less C and N enrichment from AGB stars at low metallicity, a result we attribute to NuGrid's modeling of hot-bottom burning. Different core-collapse supernova explosions and fallback prescriptions may lead to substantial variations for the accumulated ejecta of C, O and Si in the first 107 years at Z = 0.001. Finally, an online interface of the open-source SYGMA module enables interactive simulations, analysis, and data extraction of the evolution of all species formed by the evolution of simple stellar populations.

79 ASTRONOMY AND ASTROPHYSICS↗