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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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6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Effect of bisphosphonate treatment on the oim mouse middle ear ossicles' structure, composition and hearing

Hearing loss is common in people with osteogenesis imperfecta (OI or brittle bone disease). Bisphosphonates are commonly used to treat long bone fragility in children with OI. However, its impact on the bone quality of the middle ear ossicles and hearing remains unknown. This study determines whether bisphosphonates treatment itself may contribute to hearing loss in OI by evaluating its effects in the oim/oim mouse model of severe OI having normal auditory function. Specifically, this study reports the effects of alendronate (ALN), a nitrogen-containing bisphosphonate, on ossicle morphology, porosity, and elemental composition in 14-week-old oim/oim mice treated weekly, starting at 2 weeks of age. The ossicles were examined using synchrotron microtomography and X-ray fluorescence microscopy (XFM). Hearing was assessed longitudinally until 26 weeks of age by determining auditory brainstem response (ABR) thresholds in another group of mice also treated weekly starting at 2 weeks of age. ALN treatment further reduces in size the already small oim/oim ossicles, specifically in female mice. Porosity, bone composition, and hearing function, however, were generally not affected by the ALN treatment. Furthermore, ALN does not prevent joint fusions, excessive bone formations, or enlarged joint spaces in WT or oim/oim experimental groups. One ALN-treated oim/oim mouse with a bone formation in the interior of the footplate, and one ALN-treated WT mouse with a fixed footplate had frequency-specific hearing loss. Since footplate abnormalities are not observed in PBS-treated mice in this study, it remains unclear whether ALN fails to prevent these changes or contributes to their development. Future studies should investigate the mechanisms of ossicular abnormalities and bisphosphonates modulatory role in the ossicles.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2024

Disturbance of hibernating bats due to researchers entering caves to conduct hibernacula surveys

Estimating population changes of bats is important for their conservation. Population estimates of hibernating bats are often calculated by researchers entering hibernacula to count bats; however, the disturbance caused by these surveys can cause bats to arouse unnaturally, fly, and lose body mass. We conducted 17 hibernacula surveys in 9 caves from 2013 to 2018 and used acoustic detectors to document cave-exiting bats the night following our surveys. We predicted that cave-exiting flights (i.e., bats flying out and then back into caves) of Townsend’s big-eared bats (Corynorhinus townsendii) and western small-footed myotis (Myotis ciliolabrum) would be higher the night following hibernacula surveys than on nights following no surveys. Those two species, however, did not fly out of caves more than predicted the night following 82% of surveys. Nonetheless, the activity of bats flying out of caves following surveys was related to a disturbance factor (i.e., number of researchers × total time in a cave). We produced a parsimonious model for predicting the probability of Townsend’s big-eared bats flying out of caves as a function of disturbance factor and ambient temperature. That model can be used to help biologists plan for the number of researchers, and the length of time those individuals are in a cave to minimize disturbing bats.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2024

A Pseudo‐Surfactant Chemical Permeation Enhancer to Treat Otitis Media via Sustained Transtympanic Delivery of Antibiotics

Abstract Chemical permeation enhancers (CPEs) represent a prevalent and safe strategy to enable noninvasive drug delivery across skin‐like biological barriers such as the tympanic membrane (TM). While most existing CPEs interact strongly with the lipid bilayers in the stratum corneum to create defects as diffusion paths, their interactions with the delivery system, such as polymers forming a hydrogel, can compromise gelation, formulation stability, and drug diffusion. To overcome this challenge, differing interactions between CPEs and the hydrogel system are explored, especially those with sodium dodecyl sulfate (SDS), an ionic surfactant and a common CPE, and those with methyl laurate (ML), a nonionic counterpart with a similar length alkyl chain. Notably, the use of ML effectively decouples permeation enhancement from gelation, enabling sustained delivery across TMs to treat acute otitis media (AOM), which is not possible with the use of SDS. Ciprofloxacin and ML are shown to form a pseudo‐surfactant that significantly boosts transtympanic permeation. The middle ear ciprofloxacin concentration is increased by 70‐fold in vivo in a chinchilla AOM model, yielding superior efficacy and biocompatibility than the previous highest‐performing formulation. Beyond improved efficacy and biocompatibility, this single‐CPE formulation significantly accelerates its progression toward clinical deployment.

Engineering↗
DOE OSTI2024

AmeriFlux FLUXNET-1F US-CdM Cedar Mesa

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-CdM Cedar Mesa. This is the FLUXNET version of the carbon flux data for the site US-CdM Cedar Mesa produced by applying the standard ONEFlux (1F) software. Site Description - This site is located on Cedar Mesa in the middle of Bear's Ears National Monument. The land is occasionally grazed for a few months in the spring.

Bowling, David↗
DOE OSTI2026

Bat Acoustic Survey Data Collected June 2024 in and near Self Sufficiency Parcel-2 (SSP2) on the Oak Ridge Reservation (ORR)

The US Department of Energy (DOE) Oak Ridge Reservation (ORR) is located in Anderson and Roane Counties, Tennessee. A portion of the ORR, known as Self-Sufficiency Parcel 2 (SSP2) is planned for transfer for private use. The SSP2 Site is approximately 670 acres (Figure 1-1), although the current plan is to only clear and develop a portion of this acreage. Any inquiries about the land transfer and future development should be directed to DOE Oak Ridge Environmental Management, as this is beyond the scope of the Natural Resources Management Team (NRMT). NRMT records bat data for the entire ORR, including acoustic monitoring, mist netting and cave surveys. A few surveys have previously been conducted for small land transfers adjacent to SSP2 (See Appendix A), but not for the entire SSP2 area. Since bats have a large range, it was decided that collecting data while SSP2 was still accessible would be beneficial for the NRMT dataset. Acoustic data was therefore collected within and near SSP2 during the summer of 2024. This write-up is not a Biological Assessment (BA). However, the data and information provided can be used during the creation of a BA and consultations with US Fish and Wildlife Service (USFWS) in order to comply with federal directives of the Endangered Species Act of 1973 (16 U. S. C. 153 et seq.). The SSP2 site was surveyed during summer roosting/maternity season of 2024 using ultrasonic acoustic monitors to record calls from all bat species whose home ranges include the ORR. Special note was taken for presence of Federally listed Endangered and Threatened (T&E) bat species, as well as bat species which are Proposed for Federal listing, Candidate for federal listing, and state listed. Summer roosting season, from May 15 to August 15, is crucial to forest-dwelling T&E bat species for rearing young and foraging. Results of these surveys indicate the presence of three Federally listed bat species: Gray bat (Myotis grisescens--Endangered), Indiana bat (Myotis sodalis--Endangered), and Northern long-eared bat (Myotis septentrionalis--Endangered). Two additional bat species were present on the SSP2 Site: Tricolored bat (Perimyotis subflavus--Proposed for Federal listing) and Little brown bat (Myotis lucifugus—Candidate for Federal listing).

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

A Brief Survey on High Performance Computing Systems Power Management

This paper provides a survey of software-based power management techniques in High Performance Computing (HPC) systems. Seven existing power management and monitoring tools and frameworks are discussed. These are: Variorum, dynamic energy-performance optimizer (DEPO), Powersched, Bull Dynamic Power Optimizer (BDPO), Energy Aware Runtime (EAR), Global Extensible Open Power Manager (GEOPM), and PoLiMEr. Each of these tools is evaluated based on hardware abstraction, optimization methods, usability, and experimental validation. This survey highlights the diversity of approaches in managing energy efficiency, from vendor-neutral APIs to algorithm-driven power capping, and dynamic frequency adjustments. Given that energy requirements for large computational systems is increasing quickly, the importance of integrating these tools into existing HPC environments and the need for further research in this rapidly evolving field is also discussed.

97 - MATHEMATICS AND COMPUTING↗