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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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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Mortality among individuals exposed to atomic bomb radiation in utero: 1950–2012

We examined the mortality risks among 2463 individuals who were exposed in utero to atomic bomb radiation in Hiroshima or Nagasaki in August 1945 and were followed from October 1950 through 2012. Individual estimates of mother’s weighted absorbed uterine dose (DS02R1) were used. Poisson regression method was used to estimate the radiation-associated excess relative risk per Gy (ERR/Gy) and 95% confidence intervals (CI) for cause-specific mortality. Head size, birth weight, and parents’ survival status were evaluated as potential mediators of radiation effect. There were 339 deaths (216 males and 123 females) including deaths from solid cancer (n = 137), lymphohematopoietic cancer (n = 8), noncancer disease (n = 134), external cause (n = 56), and unknown cause (n = 4). Among males, the unadjusted ERR/Gy (95% CI) was increased for noncancer disease mortality (1.22, 0.10–3.14), but not for solid cancer mortality (-0.18,< -0.77–0.95); the unadjusted ERR/Gy for external cause mortality was not statistically significant (0.28, < -0.60–2.36). Among females, the unadjusted ERRs/Gy were increased for solid cancer (2.24, 0.44–5.58), noncancer (2.86, 0.56–7.64), and external cause mortality (2.57, 0.20–9.19). The ERRs/Gy adjusted for potential mediators did not change appreciably for solid cancer mortality, but decreased notably for noncancer mortality (0.39, < -0.43–1.91 for males; 1.48, - 0.046–4.55 for females) and external cause mortality (0.10, < -0.57–1.96 for males; 1.38, < -0.46–5.95 for females). In conclusion, antenatal radiation exposure is a consistent risk factor for increased solid cancer mortality among females, but not among males. The effect of exposure to atomic bomb radiation on noncancer disease and external cause mortality among individuals exposed in utero was mediated through small head size, low birth weight, and parental loss.

Public, Environmental & Occupational Health↗
NASA NTRS1951

Wind-tunnel investigation of the descent characteristics of bodies of revolution simulating anti-personnel bombs

An investigation has been conducted in the Langley 20-foot free spinning tunnel to study the relative behavior in descent of a number of homogeneous balsa bodies of revolution simulating anti-personnel bombs with a small cylindrical exploding device suspended approximately 10 feet below the bomb. The bodies of revolution included hemispherical, near-hemispherical, and near-paraboloid shapes. The ordinates of one near-paraboloid shape were specified by the Office of the Chief of Ordnance, U. S. Army. The behavior of the various bodies without the cylinder was also investigated. The results of the investigation indicated that several of the bodies descended vertically with their longitudinal axis, suspension line, and small cylinder in a vertical attitude,. However, the body, the ordinates of which had been specified by the Office of the Chief of Ordnance, U. S. Army, oscillated considerably from a vertical attitude while descending and therefore appeared unsuitable for its intended use. The behavior of this body became satisfactory when its center of gravity was moved well forward from its original position. In general, the results indicated that the descent characteristics of the bodies of revolution become more favorable as their shapes approached that of a hemisphere.

Sher, S. H.↗
NASA NTRS1972

Precision closed bomb calorimeter for testing flame and gas producing initiators

A calorimeter has been developed under this study to help meet the needs of accurate performance monitoring of electrically or mechanically actuated flame and gas producing devices, such as squib-type initiators. A ten cubic centimeter closed bomb (closed volume) calorimeter was designed to provide a standard pressure trace and to measure a nominal 50 calorie output, using the basic components of a Parr Model 1411 calorimeter. Two prototype bombs were fabricated, pressure tested to 2600 psi, and extensively evaluated.

Carpenter, D. R., Jr.↗
NASA NTRS1991

Ultrasonic Device Would Open Pipe Bombs

Piezoelectric ultrasonic transducer, energized by frequency generator and power supply, vibrates shell of pipe bomb while hardly disturbing explosive inner material. Frequency-control circuitry senses resonance in shell and holds generator at that frequency to induce fatigue cracking in threads of end cap. In addition to disarming bombs, ultrasonically induced fatigue may have other applications. In manufacturing, replaces some machining and cutting operations. In repair of equipment, cleanly and quickly disassembles corroded parts. In demolition of buildings used to dismember steel framework safely and controllably.

El-Raheb, Michael S.↗
NASA NTRS1991

Cartridge output testing - Methods to overcome closed-bomb shortcomings

Although the closed-bomb test has achieved virtually universal acceptance for measuring the output performance of pyrotechnic cartridges, there are serious shortcomings in its ability to quantify the performance of cartridges used as energy sources for pyrotechnic-activated mechanical devices. This paper presents several examples of cartridges (including the NASA Standard Initiator NSI) that successfully met closed-bomb performance requirements, but resulted in functional failures in mechanisms. To resolve these failures, test methods were developed to demonstrate a functional margin, based on comparing energy required to accomplish the function to energy deliverable by the cartridge.

Bement, Laurence J.↗
NASA NTRS1993

Ignition propagation and heat effects of propellant chips embedded in castable inhibitor using a laser flux test bomb

A castable inhibitor is applied to the aft face of the Space Shuttle Redesigned Solid Rocket Motor (RSRM) forward segment propellant grain to control propellant surface burn area. During fabrication, the propellant surface is trimmed prior to the inhibitor application. This produces a potential for small propellant chips to remain undetected on the propellant surface and contaminate the inhibitor during application. The concern was that undetected propellant chips in the inhibitor might provide a fuse path for premature propellant ignition underneath the inhibitor. To evaluate the fuse path potential, testing was performed on inhibitor samples with embedded propellant. The internal motor environment was simulated with a calibrated CO2 laser beam directed onto a sample which was placed in a 4100 kPa (600 psi) nitrogen pressurized bomb (laser bomb). The testing showed definitive results pertaining to fuse path formation. Embedded propellant chips did not autoignite until the receding heat affected inhibitor surface reached, or passed, the propellant chip. Samples with embedded propellant chips in alignment did not propagate ignition from one chip to another with separation distances as small as 0.010 cm(0.004 inc) and some as little as 0.0051 cm (0.002 in). Propellant chips with volumes approximately less than 0.025 cu cm (0.0015 cu in) (which did not propagate ignition) did not increase the inhibitor material decomposition depth more than the resulting void cavity of the burned out propellant chip. In addition, the depth of this void cavity did not increase until it was overtaken by the surrounding material decomposition depth. This was due, in part, to the retention of the protective inhibitor char layer. Samples with embedded propellant strings, whose thicknesses were below 0.023 cm (0.009 in), did not propagate ignition. Propellant string thicknesses above 0.038 cm (0.015 in) did propagate ignition. Test sample char and heat affected layer measurements and observations compared well with those from the Space Shuttle Solid Rocket Motor (SRM) Technical Evaluation Motor no. 9(TEM-9).

Bolton, Douglas E., Jr.↗
DOE OSTI2023

Early-life atomic-bomb irradiation accelerates immunological aging and elevates immune-related intracellular reactive oxygen species

Reactive oxygen species (ROS) play an important role in immune responses; however, their excessive production and accumulation increases the risk of inflammation-related diseases. Although irradiation is known to accelerate immunological aging, the underlying mechanism is still unclear. To determine the possible involvement of ROS in this mechanism, we examined 10,023 samples obtained from 3752 atomic-bomb survivors in Hiroshima and Nagasaki, who participated in repeated biennial examinations from 2008 to 2016, for the effects of aging and radiation exposure on intracellular ROS (H 2 O 2 and O 2 •- ) levels, percentages of T-cell subsets, and the effects of radiation exposure on the relationship between cell percentages and intracellular ROS levels in T-cell subsets. The cell percentages and intracellular ROS levels in T-cell subsets were measured using flow cytometry, with both fluorescently labeled antibodies and the fluorescent reagents, carboxy-DCFDA and hydroethidine. The percentages of naïve CD4 + and CD8 + T cells decreased with increasing age and radiation dose, while the intracellular O 2 •- levels in central and effector memory CD8 + T cells increased. Additionally, when divided into three groups based on the percentages of naïve CD4 + T cells, intracellular O 2 •- levels of central and effector memory CD8 + T cells were significantly elevated with the lowest radiation dose group in the naïve CD4 + T cells. Thus, the radiation exposure-induced decrease in the naïve CD4 + T cell pool size may reflect decreased immune function, resulting in increased intracellular ROS levels in central and effector memory CD8 + T cells, and increased intracellular oxidative stress.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2020

Misclassification of primary liver cancer in the Life Span Study of atomic bomb survivors

Primary liver cancer is difficult to diagnose accurately at death, due to metastases from nearby organs and to concomitant diseases, such as chronic hepatitis and cirrhosis. Trends in diagnostic accuracy could affect radiation risk estimates for incident liver cancer by altering background rates or by impacting risk modification by sex and age. We quantified the potential impact of death‐certificate inaccuracies on radiation risk estimates for liver cancer in the Life Span Study of atomic bomb survivors. True‐positive and false‐negative rates were obtained from a previous study that compared death‐certificate causes of death with those based on pathological review, from 1958 to 1987. We assumed various scenarios for misclassification rates after 1987. We obtained estimated true positives and estimated false negatives by stratified sampling from binomial distributions with probabilities given by the true‐positive and false‐negative rates, respectively. Poisson regression methods were applied to highly stratified person‐year tables of corrected case counts and accrued person years. During the study period (1958–2009), there were 1,885 cases of liver cancer, which included 383 death‐certificate‐only (DCO) cases; 1,283 cases with chronic liver disease as the underlying cause of death; and 150 DCO cases of pancreatic cancer among 105,444 study participants. Across the range of scenarios considered, radiation risk estimates based on corrected case counts were attenuated, on average, by 13–30%. Our results indicated that radiation risk estimates for liver cancer were potentially sensitive to death‐certificate inaccuracies. Additional data are needed to inform misclassification rates in recent years.

French, Benjamin↗
DOE OSTI2021

Radiation effects on atherosclerosis in atomic bomb survivors: a cross-sectional study using structural equation modeling

Past reports indicated that total-body irradiation at low to moderate doses could be responsible for cardiovascular disease risks, but the mechanism remains unclear. The purpose of this study was to investigate the association between radiation exposure and atherosclerosis, an underlying pathology of cardiovascular diseases, in the Japanese atomic bomb survivors. We performed a cross-sectional study measuring 14 clinical-physiological atherosclerosis indicators during clinical exams from 2010 to 2014 in 3274 participants of the Adult Health Study cohort. Multivariable analyses were performed by using a structural equation model with latent factors representing underlying atherosclerotic pathologies: (1) arterial stiffness, (2) calcification, and (3) plaque as measured with indicators chosen a priori on the basis of clinical-physiological knowledge. Radiation was linearly associated with calcification (standardized coefficient per Gy 0.15, 95 % confidence interval: CI [0.070, 0.23]) and plaque (0.11, 95 % CI [0.029, 0.20]), small associations that were comparable to about 2 years of aging per Gy of radiation exposure, but not with arterial stiffness (0.036, 95 % CI [-0.025, 0.095]). The model fitted better and had narrower confidence intervals than separate ordinary regression models explaining individual indicators independently. The associations were less evident when the dose range was restricted to a maximum of 2 or 1 Gy. By combining individual clinical-physiological indicators that are correlated because of common, underlying atherosclerotic pathologies, we found a small, but significant association of radiation with atherosclerosis.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Longitudinal changes in red blood cell distribution width decades after radiation exposure in atomic–bomb survivors

Red blood cell distribution width (RDW), which generally increases with age, is a risk marker for morbidity and mortality in various diseases. We investigated the association between elevated RDW and prior radiation exposure by examining longitudinal RDW changes in 4204 atomic-bomb survivors over 15 years. A positive association was found between RDW and radiation dose, wherein RDW increased by 0·18%/Gy. This radiation-associated effect increased as the participants aged. Elevated RDW was also associated with higher all-cause mortality. The biological mechanisms underlying these observed associations merit further investigation.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2023

Caribbean deepwater snappers: Application of the bomb radiocarbon age estimation validation in understanding aspects of ecology and life history

Reef fishes have been utilized as food fish throughout the U.S. Caribbean and Gulf of Mexico waters for centuries, with increasing fishing effort in recent decades. As a result, many species have experienced declines in landings, including deepwater snappers such as queen snapper Etelis oculatus and blackfin snapper Lutjanus buccanella . However, little to no peer-reviewed published research exists on basic life history parameters for either species. Confirming the accuracy of an age estimation method for a fish species is essential for ensuring sustainable fisheries management. This is because in the assessment of fisheries species population age-based parameters, including longevity, age at sexual maturity, growth rate, mortality, age-specific reproductive output, and lifetime reproductive output, are important in understanding overall life history strategies of managed stocks. The past stock assessment on U.S. Caribbean queen snapper utilized an estimated longevity of 8 y, derived from length frequencies for fish from St. Lucia. Blackfin snapper has an estimated longevity of 27 y based on a relatively small study from offshore waters of the southeastern U.S. The focus of our investigation was to estimate maximum longevity of two data-poor species in the U.S. Caribbean. The accuracy of ageing methods was tested via bomb radiocarbon age estimation validation and effects of depth on Δ 14 C in otolith cores and eye lens core values were examined. Results from our work indicate a maximum validated age of 45 y for queen snapper, and 43 y for blackfin snapper. Our findings indicate queen snapper and blackfin snapper are long-lived (> 40 y). The resulting Δ 14 C comparison between eye lens cores and otolith cores has important implications for the study of age validation, specifically when deepwater species are involved.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2022

Comparison of All Solid Cancer Mortality and Incidence Dose-Response in the Life Span Study of Atomic Bomb Survivors, 1958–2009

Recent analysis of all solid cancer incidence (1958–2009) in the Life Span Study (LSS) revealed evidence of upward curvature in the radiation dose response among males but not females. Upward curvature in sex-averaged excess relative risk (ERR) for all solid cancer mortality (1950–2003) was also observed in the 0–2 Gy dose range. As reasons for non-linearity in the LSS are not completely understood, we conducted dose response analyses for all solid cancer mortality and incidence applying similar methods (1958–2009 follow-up, DS02R1 doses, including subjects notin-city (NIC) at the time of the bombing) and statistical models. Incident cancers were ascertained from Hiroshima and Nagasaki cancer registries, while cause of death was ascertained from death certificates over entire Japan. The study included 105,444 LSS subjects who were alive and not known to have cancer before Jan 1, 1958 (80,205 with dose estimates and 25,239 NIC subjects). Between 1958 and 2009, there were 3.1 million person-years (PY) and 22,538 solid cancers for incidence analysis and 3.8 million PY and 15,419 solid cancer deaths for mortality analysis. We fitted sex-specific ERR models adjusted for smoking to both types of data. Over the entire range of doses, solid cancer mortality dose response exhibited a borderline significant upward curvature among males (P=0.062) and significant upward curvature among females (P=0.010); for solid cancer incidence, as before, we found a significant upward curvature among males (P=0.001) but not among females (P=0.624). The sex difference in magnitude of dose response curvature was statistically significant for cancer incidence (P=0.017) but not for cancer mortality (P=0.781). The results of analyses in the 0–2 Gy range and restricted lower dose ranges generally supported inferences made about the sex-specific dose response shape over the entire range of doses for each outcome. Patterns of sex-specific curvature by calendar period (1958–1987 vs 1988–2009) and age at exposure (0–19 vs 20–83) varied between mortality and incidence data, particularly among females, although for each outcome there was an indication of curvature among 0–19 year old male survivors in both calendar periods and among 0–19 year old female survivors in the recent period. Collectively, our findings indicate that the upward curvature in all solid cancer dose response in the LSS is neither specific to males nor to incidence data; it appears to depend on composition of case series and age at exposure or time. Further follow-up and site-specific analyses of cancer mortality and incidence will be important to confirm the emerging trend in dose response curvature among young survivors and unveil the contributing factors and sites.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2023

The Effect of Prostate-Specific Antigen (PSA) Test on Radiation Risk Estimate for Prostate Cancer Incidence among Atomic-Bomb Survivors

Following our previous report on the radiation doseresponse for prostate cancer incidence rates in the Life Span Study (LSS) cohort of atomic bomb survivors, we reevaluated the radiation-related risk adjusting for differences in baseline cancer incidence rates among three subsets of the LSS cohort defined by the timing of their first participation in biennial health examinations offered to the Adult Health Study (AHS) sub-cohort members and prostate-specificantigen (PSA) testing status for AHS participants: 1. nonAHS participants, 2. AHS participants before receiving PSA test, and 3. AHS participants after receiving PSA test. We found a 2.9-fold increase in the baseline incidence rates among AHS participants after receiving PSA test. After adjusting for the PSA-testing-status effects on the baseline rates the estimated excess relative risk (ERR) per Gy was 0.54 (95% CI: 0.15, 1.05), which was almost identical to the previously reported unadjusted ERR estimate (0.57, 95% CI: 0.21, 1.00). The current results confirmed that, while the PSA testing among AHS participants increased the baseline incidence rates, it did not impact the radiation risk estimate, strengthening the previously reported dose-response relationship for prostate cancer incidence in the LSS. As the use of PSA tests continue in screening and medical settings, analyses of possible effects of PSA testing should be an important aspect of future epidemiological studies of the association between radiation exposure and prostate cancer.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2021

The Science of the Bomb

Uranium is a naturally occurring element with wo isotopes of interest – U238 and U235; U235 is useful for its ability to sustain a chain reaction; Chain reactions are the fundamental way that nuclear reactors work, as well as how bombs work; Enrichment of U235 is important for both nuclear energy as well as nuclear weapons; A safety focus is at the center of all nuclear operations in the United States

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2024

A ‘Nuclear Bomb’ or Just ‘a Joke’? Groundwater Models May Help Communicate Nuanced Risks to the Great Salt Lake

The Great Salt Lake entered the zeitgeist of environmental concern in 2022 when a coalition of scientists and activists warned in a highly publicized report that the lake might be just five years away from complete desiccation, a possibility one state official warned was tantamount to an “environmental nuclear bomb”. Shortly thereafter, an unpredicted and unprecedented pluvial winter resulted in an increase in inflow, temporarily halting the lake’s decline and prompting Utah’s governor to mock the dire prediction as “a joke”, an outcome that speaks to the tension between agenda-setting and trust-building that researchers face when sharing worst-case warnings, particularly those based on short-term variability. Here, we describe a robust relationship between the lake and groundwater in the surrounding region and demonstrate how coupled models can thus be used to improve lake elevation predictions, suggesting that while the situation may not be as dire as some have warned, the lake remains at long-term risk as a result of climate warming. We further suggest that efforts to communicate the risk of future desiccation should be informed by stochastic variability and guided by long-term fluctuations in the total water storage of the endorheic lake’s watershed.

Environmental Sciences & Ecology↗