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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.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Nomenclature, Chemical Abstracts Service Numbers, Isomer Enumeration, Ring Strain and Stereochemistry: What Does Any of This Have to do with an International Chemical Disarmament and Non-Proliferation Treaty?

The Chemical Weapons Convention (CWC) is an international disarmament and non-proliferation treaty that mandates a comprehensive ban on chemical weapons. This treaty entered-into-force in 1997 and has a nearly universal membership of world states. The CWC provides definitions for what constitutes a chemical weapon and describes chemicals for which verification measures and regulatory oversight are required. These chemicals, which must be declared to the Organisation for the Prohibition of Chemical Weapons (OPCW) for verification purposes, appear in three Schedules within the CWC. The schedules list specific chemical substances and families of chemicals defined by molecular structure descriptions that allow a range of specified variable groups. The text of an international treaty provides a basis for laws and regulatory requirements at international and national levels that must be enacted to comply with treaty obligations. These laws and regulations must account for the “chemistry” that is described in the treaty text, which has been negotiated and agreed upon by world governments. In this paper, we look at some of the chemicals described within the CWC and discuss how atoms and molecules, nomenclature and Chemical Abstracts Service (CAS) numbers, isomer enumeration, ring strain and stereochemistry influence the obligations of States to an international treaty. The material draws upon the authors’ experiences from an interactive “Science for Diplomats” initiative that has provided a forum for engaging with chemical disarmament decision makers to aid in their understanding of fundamental concepts in chemistry that have impact on treaty implementation. We hope this article will spark interest from chemistry students and educators in the provision of science advice for policymakers and provide policymakers with an appreciation of the complexity and importance of understanding the language of chemistry in support of a world free of chemical weapons.

Organic Chemistry, Alkanes/Cycloalkanes, Applicati↗
DOE OSTI2023

ATM signaling modulates cohesin behavior in meiotic prophase and proliferating cells

Cohesins are ancient and ubiquitous regulators of chromosome architecture and function, but their diverse roles and regulation remain poorly understood. During meiosis, chromosomes are reorganized as linear arrays of chromatin loops around a cohesin axis. This unique organization underlies homolog pairing, synapsis, double-stranded break induction, and recombination. We report that axis assembly in Caenorhabditis elegans is promoted by DNA-damage response (DDR) kinases that are activated at meiotic entry, even in the absence of DNA breaks. Downregulation of the cohesin-destabilizing factor WAPL-1 by ATM-1 promotes axis association of cohesins containing the meiotic kleisins COH-3 and COH-4. ECO-1 and PDS-5 also contribute to stabilizing axis-associated meiotic cohesins. Further, our data suggest that cohesin-enriched domains that promote DNA repair in mammalian cells also depend on WAPL inhibition by ATM. Thus, DDR and Wapl seem to play conserved roles in cohesin regulation in meiotic prophase and proliferating cells.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2019

Increased ß-cell proliferation before immune cell invasion prevents progression of type 1 diabetes

Type 1 diabetes (T1D) is characterized by pancreatic islet infiltration by autoreactive immune cells and a near-total loss of ß-cells1. Restoration of insulin producing ß-cells coupled with immunomodulation to suppress the autoimmune attack has emerged as a potential approach to counter T1D2-4. Here we report that enhancing ß-cell mass early in life (prior to weaning) results in immunomodulation of T-cells, reduced islet infiltration and lower ß-cell apoptosis, in female NOD mice that together protect them from developing T1D. We observed that a model exhibiting ß-cell hyperplasia on the NOD background (NOD-LIRKO) displayed reduced ß-cell antigens, and islet transplantation studies showed prolonged graft survival of NOD-LIRKO islets even upon exposure to diabetogenic splenocytes in vivo. Adoptive transfer of splenocytes from the NOD-LIRKOs prevented diabetes development in pre-diabetic NOD mice, while conversely; similar protective outcomes were obtained when NOD-LIRKO splenocytes were adoptively transferred after mixing them with diabetogenic NOD splenocytes in a dose-dependent manner. A significant increase in splenic CD4+CD25+FoxP3+ regulatory T-cell (Treg) population in the NOD-LIRKO mice was observed to drive the protected phenotype since Treg depletion rendered NOD-LIRKO mice diabetic. The increase in Tregs coupled with downregulation of key mediators of cellular function, upregulation of apoptosis and activation of TGF-ß/SMAD3 signaling pathway in pathogenic T-cells favored reduced ability to kill ß-cells. These data provide novel evidence that initiating ß-cell proliferation prior to islet infiltration by immune cells alters the identity of ß-cells, improves pathologic self-reactivity of effector cells and increases Tregs to prevent progression of T1D.

Dirice, Ercument↗
DOE OSTI2018

A Framework for Assessing Alternate Proliferation Pathways In The Age Of Non-State Actors

While the nonproliferation community has long acknowledged the possibility of nuclear terrorism, its prevention has become a central focus area in recent years. For decades it has been assumed that, with access to special nuclear material (SNM), the steps to indigenously develop an improvised nuclear device are within the reach of non-state actors. At the same time, indigenous development of the SNM itself has generally been dismissed as it is perceived as an infeasible option. Recognizing how recent trends of technology democratization, the open exchange of information, and globalization have eroded certain barriers to proliferation by non-state actors, this research explores whether indigenous development of SNM is feasible given the current capabilities of non-state actors. In addition, methods were developed to screen which approaches should be further investigated to devise and enact general and non-state actor specific countermeasures.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2016

Transactive Home Energy Management Systems: The Impact of Their Proliferation on the Electric Grid

Approximately 100 million singlefamily homes in the United States account for 36% of the electricity load, and often they determine the peak system load, especially on hot summer days when residential air-conditioning use is high. Traditional building power profiles are changing. Currently, there is an increased use of energy-efficient building materials and designs, which decreases building loads. In addition, there is an increased adoption of rooftop solar photovoltaic (PV), which leads to bidirectional power flow and significant power ramps as PV output decreases in the late afternoon. Building power profiles are likely to change even more as residential energy storage products proliferate. Therefore, a better understanding of residential electricity demand is key to addressing the envisioned transition of the electric power system from its traditional structure to one that is transactive.

25 ENERGY STORAGE↗
DOE OSTI2022

SIRT1 targeted by miR ‐211‐5p regulated proliferation and apoptosis of Dex‐treated growth plate chondrocytes via mediating SOX2

Abstract Dexamethasone (Dex) is reported to cause bone growth retardation in children, which is associated with the increased apoptosis and decreased proliferation of growth plate chondrocytes. Sirtuin 1 (SIRT1) plays an important role in chondrocyte function and homeostasis. Thus, we further explored the regulatory mechanism of SIRT1 in Dex‐induced growth plate chondrocyte dysfunction. SIRT1 expression was detected in Dex‐treated growth plate chondrocytes using RT‐qPCR and western blot assay. The modulation of SIRT1 on SOX2 expression was evaluated. Besides, we identified that SIRT1 was targeted by miR‐211‐5p using TargetScan and RNA pull‐down assay. A loss‐of‐function assay was performed to evaluate the effects of miR‐211‐5p on Dex‐induced growth plate chondrocyte dysfunction in vitro and in vivo. We found that SIRT1 was downregulated in Dex‐treated growth plate chondrocytes. The expression of SOX2 was upregulated by overexpression SIRT1. Meanwhile, downregulation of SOX2 weakened the positive function of SIRT1 overexpression on Dex‐induced growth plate chondrocytes dysfunction. Subsequently, we confirmed that SIRT1 was targeted by miR‐211‐5p. MiR‐211‐5p inhibitor increased the expression levels of SIRT1 and SOX2, and restored the Dex‐treated growth plate chondrocyte function. Animal assays further demonstrated that the effects of miR‐211‐5p on the growth plate chondrogenesis. In conclusion, our data suggest that SIRT1 exerts a protective effect on growth plate chondrocyte under Dex stimulation. MiR‐211‐5p/SIRT1/SOX2 axis regulates the process of Dex‐inhibited growth plate chondrogenesis.

Cheng, Deliang↗
DOE OSTI2017

The Proliferation of Unmanned Aerial Vehicles: Terrorist Use, Capability, and Strategic Implications

There has been unparalleled proliferation and technological advancement of consumer unmanned aerial vehicles (UAVs) across the globe in the past several years. As witnessed over the course of insurgency tactics, it is difficult to restrict terrorists from using widely available technology they perceive as advantageous to their overall strategy. Through a review of the characteristics, consumer market landscape, tactics, and countertactics, as well as operational use of consumer-grade UAVs, this open-source report seeks to provide an introductory understanding of the terrorist-UAV landscape, as well as insights into present and future capabilities. The caveat is evaluating a developing technology haphazardly used by terrorists in asymmetric conflicts.

42 ENGINEERING↗
DOE OSTI2019

Understanding the Impact of the Secondary Market on Proliferation

Economic, technological, and social trends are changing the way consumers think about used commodities. Many consumers are now more willing to consider used or remanufactured goods. Simultaneously, new technological innovations are arising that make it more cost-effective to remanufacture these goods and easier to find buyers for them. Together, these changes have led to rapid growth in the secondary market and, along with it, a new threat: the potential export of used, listed weapons of mass destruction (WMD)-related commodities by secondary market resellers who are unaware of export control requirements. While the export of WMD-related commodities is regulated throughout the commodity’s lifetime, knowledge of those export control requirements is sometimes lost as commodities are sold and resold. As such, the secondary market for listed commodities pose proliferation risks and export control challenges that may not be well understood by the U.S. Government.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2020

MSR Proliferation Resistance and Physical Protection White Paper

Molten Salt Reactors (MSRs) have seen a resurgence of interest in the past decade around the world. Support for these activities is provided from both national and private sources. The largest difference from the 2011 GIF MSR PR&PP evaluation consequently is the transition from evaluating academic systems focused on exploring the technical potential of MSRs to those of companies and countries focusing on near-term deployment. A wide variety of designs currently exist ranging from solid to liquid-fueled designs, with salt processing on-site or off-site, and a variety of fuel choices. As such, the proliferation resistance and physical protection aspects will have significantly more variation depending on reactor design than the other advanced reactors. The rapid introduction and evolution of innovative MSR designs inevitably means that technology specific details of overview reports, such as this one, become rapidly outdated. Consequently, this report focuses on essential features required for any MSR rather than specific design aspects.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2022

Numerical Simulations of Non-Proliferation Experiments

We have implemented a set of numerical simulations to numerically investigate the outcomes of non-proliferation experiments. The high explosive (HE) in the simulations is in the form of a cylinder. The two-dimensional simulations are carried out in the r-z cylindrical coordinate, and the three-dimensional simulation is in the Cartesian coordinate. From the simulation, the cavity formed after detonation stops its expansion after about 0.15 sec. At the time the cavity stops expanding, the cavity shape seems quite spherical although the initial HE is in the shape of cylinder, but the radius in the vertical direction, which is about 19.7m, is a little less than the one in the horizonal direction, which is about 21.5m. Although there is no layer of air between the HE and tuff in real experiments, in addition to the simulations without air, we add a layer of air in one simulation to assess any possible influence of the air on the shape of the cavity.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2021

Feature Extraction: Improving Remote Sensor Classification of Non-Proliferation

This research focuses on developing algorithms for nuclear non-proliferation detection using remote sensor modeling. To improve the performance of classification models, we implemented a data pipeline with feature extraction. This pipeline takes raw data and transforms it into smaller data points called features that still describe the model. Improving this classification works towards the departments of energy’s missions of ensuring American’s security and prosperity by creating technology that addresses nuclear challenges. To conduct this analysis, we used the Python programming language and some key packages, including tsfresh and TSFEL. Originally tsfresh was selected because it has the most statistical features out of all the packages. Later TSFEL was incorporated due to the additional features it can extract from data, such as temporal and spectral. However, feature extraction becomes challenging in the presence of missing values. In this case, two additional Python packages were added to our workflow, NumPy and pandas, allowing for the feature extraction process to handle unknown values. Our data pipeline was tested on data collected from a simulation that describes the process state of a physical example. The results show the pipeline’s capability to consume and extract a total 17 features from tabular data. Future work includes producing classifications using decision tree-based models such as XGBoost and improving data collection by analyzing feature importance.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2019

Trade Compliance Insurance Product: Revisiting the feasibility of an insurance product to strengthen trade compliance and reduce proliferation risks

In October 2018, Pacific Northwest National Laboratory (PNNL) published a report (PNNL-28094) in collaboration with the Stimson Center on the feasibility of an insurance product that would reduce proliferation risks associated with small and medium-sized enterprises by encouraging stronger trade control compliance. This preliminary report concluded that a Trade Compliance Insurance Product (TCIP) is feasible and identified existing insurance analogs, challenges, and outstanding questions for further industry outreach. From October 2018 to September 2019, PNNL attempted to validate this preliminary report through a series interviews with representatives from the manufacturing, finance, insurance and shipping industries. This report follows up on the initial 2018 Report and summarizes the findings of the industry interviews related to the TCIP and makes recommendations for the next steps and insurance incentives more broadly.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2024

Considerations in Proliferation Resistance Optimization of Medical Isotope Facilities

The U.S. Proliferation Resistance and Optimization (PRO-X) program provides a framework for design optimization of a system, component, or feature of a nuclear facility to minimize potential Special Nuclear Material production and diversion pathways while optimizing system performance for peaceful, asintended missions.

Groden, Nicholas D.↗
DOE OSTI2025

Study of Applications of Radiological Data Fusion for Nuclear Security and Non-proliferation Applications

This report describes the radiological Scene Data Fusion (SDF) technology and the potential to apply the SDF technology to a variety of problems related to nuclear non-proliferation, radiological security, and other missions related to the national nuclear security agency and the US government, more broadly. The application space was conceived by both the authors of this report and the many scientists and stakeholders they interviewed. In order to successfully apply the SDF technology to the various applications, further research and development is often necessary and those R&D steps are also outlined herein.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
NASA NTRS1975

Effects of weightlessness on tissue proliferation

The repair of bone marrow stroma following mechanical injury was studied to obtain baseline data for a proposed space experiment regarding the effect of weightlessness on marrow stroma and other proliferating cell systems.

Crosby, W. H.↗
NASA NTRS1981

Effect of weightlessness on lymphocyte proliferation

An experiment to study the effect of weightlessness on lymphocyte proliferation to detect possible alteration of the cells responsible for the immune response during long-duration space flights is described. Human lymphocytes in culture medium will be delivered shortly before launch in an incubator which will be kept at 37C. Mitogen will be added to the culture. A control without mitogen will be run in parallel. After 70 hours of incubation, radioactive thymidine will be added. After two hours, cellular activity will be stopped by fixation and incubator power switched off. Later, the amount of incorporated thymidine will be determined and the cell morphology and the distribution of cell organelles will be investigated.

Cogoli, A.↗