Test Explosions Research Articles

The comprehensive Nuclear Test Ban Treaty and Seismological Research

Even as I write, the U.S. Senate is conducting hearings on the issue of ratification of the Comprehensive Nuclear Test Ban Treaty (CTBT), signed by President Clinton on September 24, 1996, and by more than 140 other nations subsequently. Building upon several previous bilateral and multilateral treaties that have partially constrained nuclear weapons testing since 1963, the CTBT mandates that “Each State Party undertakes not to carry out any nuclear weapon test explosion or any other nuclear explosion, and to prohibit and prevent any such nuclear explosion at any place under its jurisdiction or control” (Article 1.1, Comprehensive Nuclear Test Ban Treaty). If globally embraced, the CTBT will shut the door on the nuclear weapons testing era after 52 years and more than 2090 nuclear explosions around the world. As the Senate considers the many political, technical and philosophical issues that frame this particular arms control endeavor, it is important...

Achieving Effective Medical Information Security: Understanding the Culture

Cet article decrit, du point de vue d'un clinicien generaliste, une solution pour l'implementation de dossiers concernant les patients en toute securite, ainsi que les strategies mises en place pour cette implementation. Cet article souligne donc l'importance de la securite pour la confidentialite de ces dossiers, mais aussi la difficulte de mettre en place un systeme de protection de l'information sur

Cancer mortality in French Polynesia between 1984 and 1992.

A mortality study of French Polynesia in the period 1984-92, although limited by the small population living close to the test sites and the high proportion of deaths attributed to ill-defined causes, found no excess of cancer that could confidently be attributed to the 41 atmospheric test explosions in 1966-74. A study of cancer incidence is planned.

Improving teleseismic event locations using a three-dimensional Earth model

Abstract A comparison is made between seismic event locations derived from standard spherically symmetric Earth models (JB, PREM, IASP91) and a recent Earth model (S&P12/WM13) that incorporates large-scale lateral heterogeneity of P- and S-wave velocities in the mantle. Events with known hypocentral coordinates are located in the different Earth models using standard methods. Two sets of events are considered: a data set of 26 explosions, including primarily nuclear weapons test explosions and peaceful nuclear explosions in the United States and former USSR; and a published data set of 82 well-located earthquakes with a more even global distribution. IASP91 and PREM are shown to offer similar errors in event location and origin time estimates with respect to the JB model. The three-dimensional (3D) model S&P12/WM13 offers improvement in event locations over all three one-dimensional (1D) models with, or without, station corrections. For the explosion events, the average mislocation distance is reduced by approximately 40%; for the earthquakes, the improvements are smaller. Corrections for crustal thickness beneath source and receiver are found to be of similar magnitude to the mantle corrections, but use of station corrections together with the three-dimensional mantle model provide the best locations.

237Np in hemp-palm leaves of Bontenchiku for fishing gear used by the Fifth Fukuryu-Maru: 40 years after "Bravo".

The alpha radioactive components in the Hemp-palm of Bontenchiku were determined with emphasis on the measurement low-level 237Np by alpha-ray spectrometry after chemical separation. Bontenchiku is a kind of fishing gear for long-line fishing used by the Fifth Fukuryu-Maru (Lucky Dragon). This gear was exposed to fallout from the second thermonuclear test explosion (Bravo) at Bikini Atoll in March 1954. The 237Np content in the Bontenchiku sample was determined to be 11.5 +/- 0.8 mBq g(-1), with an activity ratio of 237Np:239,240Pu and an atom ratio of 237Np:239Pu estimated to be (2.2 +/- 0.2) x 10(-3) and 0.42 +/- 0.04, respectively. The data showed the existence of a chain reaction of 238U and its ratio to be 237Np:239Pu, as well as the presence of 237U at the time of fallout from Bravo event in March 1954.

New information on nuclear tests

The recently established SCOPE‐RADTEST (Scientific Committee on Problems of the Environment‐Radioactivity from Nuclear Test Explosions) programme is examining releases of radioactivity due to nuclear detonations which have occurred at various test sites around the world, for peaceful and military purposes, taking into consideration both ecological and human effects. Presents the background to this programme, together with a summary of the proceedings of RADTEST’s North Atlantic Treaty Organization Advanced Research Workshop meetings held during 1994 in Vienna, Austria, and Barnaul, Russia, and of the 1995 meeting in Brussels/Liège, Belgium.

Fair Test: Charting a Course for Testing Reform

America is in the midst of a testing explosion. Tests, especially norm-referenced, multiple choice tests, have proliferated so greatly over the past several decades here and, increasingly, worldwide that people feel their impact at many different points in their lives. A growing concern in the United States about this proliferation brought national leaders of civil rights, consumer, education, and student organizations together in 1985 for a conference to discuss testing issues. Though all the groups were deeply concerned about the growing impact of standardized exams, none had the resources to make testing reform a top priority. Conference participants wanted to create an organization that would function as a bridge between the civil rights community and education reformers. The National Center for Fair and Open Testing (FairTest) was the result, and it remains the only national organization devoted solely to testing reform. FairTest is committed to advancing assessment systems, policies, and practices that help ensure fairness, equity, and excellence for all members of society. Testing often creates and reinforces barriers to equal opportunity based on race, class, gender, language, culture, and disability. The history of testing is rife with examples of how an often flawed technology is misused to determine the fates of individuals and to shape policy decisions:

90Sr and239+240Pu238Pu241Am in some samples of mushrooms and forest soil from Poland

Strontium-90, plutonium and americium activity concentrations in a few samples of forest soils, some species of mushrooms and fern leaves have been determined. These results are compared with cesium activity concentrations in the same materials obtained in a previous work. Radiochemical procedures are described. The origin of the contamination (Chernobyl accident or nuclear test explosion release) is discussed. The90Sr activity concentration ranges from 0.6 Bq/kg (mushroom samples) to 48.4 Bq/kg (fern leaves). For239+240Pu, it ranges from not detected above background (mushrooms, fern) to 10.8 Bq/kg (humus layer of forest soil). The maximum concentration of241Am is found to be 2.4 Bq/kg (humus sample) and for238Pu it is 0.85 Bq/kg (also in the humus sample).

Regionalization of International Whale Management: The Case of the North Atlantic Marine Mammals Commission

This article reviews the evolution of the North Atlantic Marine Mammals Commission (NAMMCO) and considers its relations with the International Whaling Commission (IWC) and other international institutions concerned with marine resource management. Starting out in 1988 with a conference to address their common concerns, the four parties of the Faroe Islands, Greenland, Iceland and Norway in 1990 set up a North Atlantic Committee for Coordination of Marine Mammals Research (NAC), thereby institutionalizing the information function crucial to management. The regulation function was attended to when NAMMCO was established with a scientific committee and a council in 1992. With a management committee and the scientific committee being operative in 1993, the regime appears to have been steadily evolving towards a prominent role in North Atlantic marine mammals management. The preservationist inclination of most IWC members is identified as a major driving force, but also important are the development of a multispecies perspective in fisheries science and the coastal states' fear of creeping jurisdiction on the part of an international organization. Problems of compatibility with the IWC are found to be minor at this stage, while NAMMCO rests firmly on the legal bases provided by the 1982 Law of the Sea Convention and the Agenda 21 adopted by UNCED in 1992. The real threats to marine mammals are impacts from pollution, seismic survey shooting, and nuclear test explosions, rather than harvest. A relevant future policy area for the IWC is therefore the task of informing its member governments of the effects of environmental degradation on whales, while the management issues could be shifted to appropriate regional organizations that can manage whales on a sustainable basis in relation to their role in the ecosystem.Key words: resource management, whales, regionalization, NAMMCO, WC

Early history of Los Alamos with emphasis on the two Van de Graaff accelerators from the University of Wisconsin

The early involvement of the author in the nuclear bomb project in the period commencing January 1942 at Madison, Wisconsin and ending July 16, 1945 with the test explosion at Trinity site is discussed. The text is based on a historical talk.

Impotence: A patient's goal-directed approach to treatment

The past decade has seen a better understanding of the physiology of erection and the pathophysiology of impotence as a result of considerable innovative research. These advances also introduce a new era in the diagnosis and treatment of impotence. Many functional tests and effective medical and surgical treatments are now available. With the sudden explosion of these many tests and therapies, clinicians are often confronted by questions such as: What constitues an adequate workup? What is the treatment of choice of arteriogenic impotence? Is nocturnal penile tumescence testing necessary? Is penile arteriography necessary? Over the past several years, the author has been using a patient's goal-directed approach to the diagnosis and treatment of impotence. This approach is based on (1) the most recent advances of diagnostic technique and therapy of impotence and (2) the patient's physical and mental health, motivation, and goal. This article briefly summarizes this practical patient's goal-directed management of impotence.

CIGUATERA IN THE PACIFIC: A LINK WITH MILITARY ACTIVITIES

Ciguatera fish poisoning is widespread in the Pacific. Outbreaks and the rise in incidence of the disease are related largely to military activities that disturb coral reef ecology. Nuclear test explosions and the setting up of the infrastructure for these tests are major components of such military activity.

Nuclear Weapons Testing

NEWS ANALYSIS Michael Heylin , C&EN Washington Ever since the first nuclear test explosion 43 years ago, there have been efforts to ban, or at least constrain, such tests. Such efforts have been spotty and have met with only modest success. For 25 years there have been treaty limits on where tests can be conducted: They must be underground. For 12 years there have been limits on their size: not larger than the equivalent of 150 kilotons of TNT. But these constraints have done nothing to hamper development and deployment of new nuclear weapons systems. There are no treaty limits on the number of tests and they go on unabated. Last year there were 47 worldwide. The long-term average is 42 per year. That first nuclear blast, which brightened the early morning sky near Alamogordo, N.M., on July 16, 1945, has been followed by more than 1750 nuclear explosions conducted by at least six nations. Nuclear ...

Yield estimation from spectral amplitudes of direct P and P coda recorded by the wake island deep ocean hydrophone array

Abstract Spectral amplitudes of direct P and P coda between 0.5 and 6 Hz have been measured for 14 Eastern Kazakh test explosions using 8 hydrophones of the Wake Island Array, and a new model for these data has been developed to estimate relative yields of those explosions. Each log spectral amplitude is considered to be the sum of four parameters and an error term. Three parameters are frequency-dependent and represent: (1) the average Eastern Kazakh spectrum at the Wake Island Array; (2) the spectral shape characteristics unique to each event; and (3) the station or hydrophone corrections. The fourth parameter represents relative yield. A total of 346 parameters, including the 14 relative yields, were needed to model all 901 spectral amplitudes that were measured, and first-order linear regression techniques were used to invert the data for these parameters. Standard deviations of the computed relative yields are very small, averaging only 0.015 mb units. Deviations between the relative yields and their corresponding relative NEIS body-wave magnitudes, however, are larger, averaging 0.14 mb units. This difference is interpreted to be an indicator of the level of inhomogeneity in the worldwide pattern of energy radiated from Eastern Kazakh tests. There is evidence that this pattern can be correlated with the precise epicentral location of each explosion within the test site and is due to focusing and defocusing near the source. It is proposed that the yield of a large explosion might be disguised by siting the explosion at a location that selectively defocuses energy towards continents where most seismic stations are located. The precision with which a relative yield is determined from the data of any single hydrophone averages 0.035 mb units. Thus, the model appears to provide a very stable measure of yield. Errors associated with frequencies greater than 2 Hz are only slightly greater than errors associated with frequencies less than 2 Hz, verifying the utility of using the higher frequencies observed in direct P and P coda to estimate yield.

Gamma-ray spectrum of the radioactive dust produced by the super-hydrogen bomb test explosion on March 1, 1954

The super-hydrogen bomb test explosion, the so-called Bravo test of a fission-fusion-fission bomb, was carried out on Bikini Atoll in the mid-Pacific on March 1, 1954. Twenty-three Japanese fishermen on board a fishing boat about 90 miles north-east of the test site were attacked unexpectedly by the fallout, radioactive fine debris of coral reef. Within several months after the accident by radiochemical analysis about 20 different nuclides of fission products and, in addition, a considerable amount of 235U were discovered from the fallout. As we have been preserving a minute amount of the original fallout dust collected on board the fishing boat 31 years ago, measurements of γ rays from it have recently been used to find some active nuclides, if still existing. In the γ-ray spectrum observed there exist evident peaks of γ and X-rays from 241Am, 155Eu, 137Cs, and 60Co. Absolute intensities of these four nuclides, still remaining 31 years after the explosion of the bomb, have been estimated. Some discussion on our finding is presented.

Monitoring the tests: Missile flights and test explosions are watched closely to determine whether an adversary's new weapons might upset the strategic balance

US monitoring capabilities related to the surveillance of Soviet strategic forces are reviewed and assessed. Data collected during the testing of military systems and the information derived from it are discussed. The author describes various information gathering systems (satellites, radars, ground sensors, sea sensors) used in the detection of missile telemetry signals, and of land-based military systems. Emphasis is on the detection of Soviet nuclear weapon and missile testing along with their implications for strategic arms limitation treat constraint verification.

Usefulness of oesophageal pH monitoring

Gastro‐oesophageal reflux (GOR) is a common paediatric problem which usually in the past has been diagnosed clinically, perhaps backed up by the barium oesophagogram. In the past 10 years, there has been a proliferation of further diagnostic techniques for GOR, possibly reflecting the inability of any single test to make a definitive diagnosis. The justification for this explosion of tests and the need to make a definitive diagnosis is two fold. Firstly, we know that GOR can cause significant disabilities which are often difficult to diagnose or determine the cause of (e.g. recurrent respiratory disease and sudden infant death syndrome),1 and secondly, an effective model of surgical therapy is now available.2

Polonium-210 fallout from the 1980 eruption of Mount St. Helens and the mystery cloud of 1982.

The amount of excess 210Po activity injected into the atmosphere by the 18 May 1980 eruption of Mount St. Helens was greater than that of 90Sr released by the 16 October 1980 Chinese test explosion of a 0.2 to 1 megaton nuclear device. The occurrence of a ‘mystery’ cloud prior to the 28 March 1982 eruption of El Chichon volcano was accompanied by an increase in the 210Po/210Pb ratio in rain samples collected at Fayetteville, Arkansas, during the months of January and February, 1982.

Radiation Exposure and Cancer

To the Editor.— The twofold excess risk of leukemia reported by Caldwell et al (1980;244:1575) in military personnel present at the nuclear test explosion Smoky in 1957 provides additional evidence that fallout from nuclear testing increases the risk of cancer. While the study is small, its positive findings are consistent with other studies, and the authors' risk estimates are conservative owing to their method of computation. The authors estimated that a radiation dosage of about 70 rad would be necessary to produce the carcinogenic effect found, but available film badges only showed dosages of 0.5 to 1.0 rad. This inconsistency can be explained in one of the following ways: (1) the results of the studies are due to chance, bias, or confounding; (2) low levels of radiation may cause cancer more frequently than previously thought; or (3) the radiation received during the nuclear test was much greater than originally estimated

Fallout 239Pu, 240Pu and 90Sr in surface-air in Ibaraki-Prefecture, Japan.

Measurements of 239, 240Pu and 90Sr were performed on air-dust samples collected by means of filtration with cellulose-asbestos filter at Ibaraki prefecture, Japan during 1974 to 1979. The ranges of 239, 240Pu and 90Sr content determined in these samples are 0.041-1.9 microBq/m3-air (1.1-52 aCi/m3-) and 2.3 87 microBq/m3-air (0.062-2.3 fCi/m3) respectively. The activity ratios of 239, 240Pu/90Sr are found to be in a range between 0.008 to 0.026 with a mean value of 0.017. General trend on time variation of the content of 239, 240Pu and 90Sr in the surface air was in similar pattern each other. The content of these nuclides increased after the Chinese nuclear test explosions, and also in spring seasons with the exception of a few cases.