Natural Analogues: Alamosa River Monzonite Intrusive into Tuffaceous and Andesitic Rocks

1982 ◽  
Vol 15 ◽  
Author(s):  
D. G. Brookins ◽  
M. S. Abashian ◽  
L. H. Cohen ◽  
A. E. Williams ◽  
H. A. Wollenberg ◽  
...  
Keyword(s):  
Fission Product ◽  
Conceptual Models ◽  
Laboratory Data ◽  
Hydrothermal Systems ◽  
Rock Matrix ◽  
Natural Processes ◽  
Natural Analogues ◽  
Time Periods ◽  
Over Time

This project encompasses investigations of selected natural analogues of minerals and rocks containing radioelements and fission-product elements, to ascertain how radionuclides and their daughter elements may migrate from sites of origin in response to long-term natural processes such as heating due to an igneous intrusion, circulating hydrothermal systems, diffusion through the rock matrix, weathering and erosion. Comparison of natural occurrences with conceptual models based on laboratory data will furnish a test of such models over time periods comparable to or longer than those expected for a repository.

Natural Analogues: Their Application to the Prediction of the Long-Term Behavior of Nuclear Waste Forms

1986 ◽  
Vol 84 ◽  
Author(s):  
Rodney C. Ewing ◽  
Michael J. Jercinovic
Keyword(s):  
Nuclear Waste ◽  
Borosilicate Glass ◽  
Large Scale ◽  
Laboratory Data ◽  
Waste Form ◽  
Long Time ◽  
Natural Analogues ◽  
Long Term Behavior ◽  
Nuclear Waste Forms

AbstractOne of the unique and scientifically most difficult aspects of nuclear waste isolation is the extrapolation ofshot-term laboratory data (hours to years) to the long time periods (103-105 years) required by regulatory agencies for performance assessment. The direct verification of these extrapolations is not possible, but methods must be developed to demonstrate compliance with government regulations and to satisfy the lay public that there is a demonstrable and reasonable basis for accepting the long-term extrapolations. Natural analogues of both the repository environment (e.g. radionuclide migration at Oklo) and nuclear waste form behavior (e.g. alteration of basaltic glasses and radiation damage in minerals) have been used to demonstrate the long-term behavior of large scale geologic systems and, on a smaller scale, waste form durability. This paper reviews the use of natural analogues to predict the long-term behavior of nuclear waste form glasses. Particular emphasis is placed on the inherent limitations of any conclusions that are based on “proof” by analogy. An example -- corrosion of borosilicate glass -- is discussed in detail with specific attention to the proper and successful use of natural analogues (basaltic glass) in understanding the long-term corrosion behavior of borosilicate glass.

scholarly journals The spectrum of biopsy-proven glomerular diseases in a tertiary Hospital in Southern Brazil

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Gustavo Gomes Thomé ◽  
Talissa Bianchini ◽  
Rafael Nazario Bringhenti ◽  
Pedro Guilherme Schaefer ◽  
Elvino José Guardão Barros ◽  
...  
Keyword(s):  
Nephrotic Syndrome ◽  
Temporal Variation ◽  
Kidney Biopsy ◽  
Systemic Vasculitis ◽  
Laboratory Data ◽  
Age Group ◽  
Glomerular Diseases ◽  
Nephritic Syndrome ◽  
Time Periods ◽  
Over Time

Abstract Background The prevalence and distribution of glomerular diseases differ among countries, and the indication to perform a kidney biopsy varies among centres. In this study, we assessed the prevalence of primary and secondary glomerulopathies based on histological diagnoses, and the correlation between glomerulopathies and demographic and clinical data was evaluated. Methods In this study, 1051 kidney biopsies were retrospectively reviewed between 2000 and 2018. Patient demographic, clinical and laboratory data were assessed. The prevalence of primary glomerulonephritis (PG) and secondary glomerulopathies (SG), as well as tubulointerstitial diseases (TIDs), hereditary nephropathies (HNs) and other diagnoses, were determined. The frequency of primary and secondary glomerulopathies was evaluated by age group, and the temporal variation in frequencies across three time periods (2000-2005, 2006-2011, and 2012-2018) was reported. Results The prevalence of SG predominated (52.4%), followed by PG (29.6%), other diagnoses (10.7%), TID (6.6%) and HN (1.1%). Among the primary forms of glomerular disease, focal segmental glomerulosclerosis (FSGS) was the most common (37.3%), followed by IgA nephropathy (IgAN, 24.4%), membranous nephropathy (MN, 18.6%) and minimal change disease (MCD, 8.4%). Lupus nephritis (LN, 41.1%) was most common in patients with SG, followed by diabetic kidney disease (DKD, 17.8%), systemic vasculitis (SV, 10.2%) and secondary FSGS (2nd FSGS, 10%). Nephrotic syndrome was the most common clinical presentation in patients with PG and also in patients with DRD and 2nd FSGS, whereas in patients with IgAN and SV, nephritic syndrome was the main presentation. For the age group between 18 and 50 years, LN, FSGS and IgAN predominated; for patients aged between 51 and 65 years, the proportion of DKD and 2nd FSGS increased, and SV was more common in patients > 65 years. The temporal variation in PG across the three time periods showed a statistically significant increase in IgAN (p = 0.001) and a reduction in FSGS over time (p < 0.001). In SG, there was a reduction in LN (p = 0.027) and an increase in DKD (p < 0.001) over time, with a tendency for 2nd FSGS to decrease over time (p = 0.053). Conclusions In the studied kidney biopsy registry, FSGS and IgAN were the most prevalent diagnoses in patients with PG, and LN and DKD were the most prevalent in patients with SG. Nephrotic syndrome was the major indication for biopsy. When comparing the temporal variation in glomerulopathies, there was a reduction in FSGS and an increase in IgAN in patients with PGs over time, and for patients with SGs, there was a reduction in LN with an increase in cases of DKD over time.

Short- and Long-Term Effects of Auxiliary Labels on Patient Knowledge of Precautionary Drug Information

1988 ◽  
Vol 22 (6) ◽  
pp. 470-474 ◽  
Author(s):  
Candace S. Brown ◽  
Brenda L. Solovitz ◽  
Stephen G. Bryant ◽  
Brock G. Guernsey ◽  
Seymour Fisher
Keyword(s):  
Drug Information ◽  
Controlled Study ◽  
Control Group ◽  
Long Term Effects ◽  
Short Term ◽  
Short And Long Term ◽  
Time Periods ◽  
Experimental Group ◽  
Over Time

The purpose of this study was to determine the efficacy of auxiliary prescription labels in educating outpatients about medicines at two different time periods. Five hundred fifty-nine patients were randomly assigned either to an experimental group or a control group; each person in the experimental group received a prescription bottle to which one study auxiliary label (“sticker”) had been affixed, and those in the control group received bottles with no study sticker attached. Patients were interviewed by telephone approximately one week or two months after prescription pick up. Patients who had the study sticker affixed to their prescription bottle were significantly more knowledgeable after one week about precautionary information than those patients who did not receive stickers; however, sticker-group patients receiving the delayed interview incorrectly attributed many precautions to their medication. This is the first controlled study to document that auxiliary labels increase short-term knowledge about medications, and to suggest that the same labels may result in an inappropriate generalization over time.

Thorough Testing of Performance Assessment Models: The Necessary Integration of In Situ Experiments, Natural Analogue Studies, and Laboratory Work

1997 ◽  
Vol 506 ◽  
Author(s):  
W. Russell Alexander ◽  
Andreas Gautschi ◽  
Piet Zuidema
Keyword(s):  
Performance Assessment ◽  
Laboratory Experiments ◽  
Field Experiments ◽  
Laboratory Data ◽  
Short Term ◽  
Natural Analogues ◽  
Long Timescales ◽  
Waste Repositories

ABSTRACTRepositories have to isolate radioactive waste (radwaste) and some toxic wastes from the environment for hundreds to hundreds of thousands of years. For many scientists and engineers, and especially the general public, such time spans are beyond comprehension and, consequently, they have grave doubts as to the safety of any such waste repositories. That repository performance over these long time scales can only be assessed by the use of complex mathematical models (normally called performance assessment, or PA, models) only adds to the mistrust of many. How then can people be convinced that it is possible to assess the performance (and thus ensure the safety) of a repository over the long timescales of interest? One way is to address the robustness of the PA models, by clearly indicating the form and extent of model testing carried out within the repository PA. Not only can this show that the individual component parts of the complex structure which constitutes most PA models have been checked, but also that the ‘mathematical black boxes’ constitute an acceptabe representation of the repository system.Part of the problem undoubtedly lies in the unusual nature of radwaste disposal: in most major engineering projects, such as bridge construction or aerospace engineering, the designs are tested against a range of laboratory experiments backed up by expert judgement based on experience with the same or similar systems. Here repository design deviates from standard engineering practice in that no high-level waste (and only a few low- and intermediate-level waste) repositories yet exist and, even when they do, testing their compliance to design limits will be somewhat difficult due to the time scales involved. In addition, the irrational fear of most things radioactive means that most people require some greater form of ‘proof’ that a repository is safe than they are willing to accept for other engineered systems. This being the case, significant additional effort must be expended within the radwaste industry to make it completely clear that the PA models can adequately predict the long-term behaviour of a repository.Traditionally, PA modellers have placed much weight on laboratory data for the construction and testing of PA models and, with only a few exceptions, have not integrated in their PA reports data from natural analogues and in situ experiments. The over-dependence on laboratory data is understandable in that the information is produced under well understood, fully controlled conditions and thus the modellers feel they can place a high degree of confidence in the results obtained. Unfortunately, the full complexity of a repository cannot be re-created in a laboratory and it is necessary to address processes which are influenced by natural heterogeneities, which include large degrees of uncertainty and which operate over very long timescales. In this case, it is necessary to supplement laboratory data with information from in situ field experiments and natural analogues.The advantage of natural analogues over short-term laboratory experiments is that they enable study of repository-like systems which have evolved over the geological timescales of relevance to a radwaste repository safety assessment (rather than the days to months usual in laboratory tests). However, by their very nature, natural analogues often have ill-defined boundary conditions which may be better assessed under the well constrained (if less relevant) conditions of a laboratory. Well designed, realistic in situ field experiments can bridge the gap between the laboratory and natural analogues by offering repository relevant natural conditions with some of the constraints of the laboratory (and intermediate timescales). In short, combining information from the three sources (long-term and realistic, if poorly defined, natural analogues, medium-term, better constrained, in situ field experiments and short-term, less realistic but well defined laboratory studies) can provide greater confidence in the extrapolation of laboratory derived data to repository relevant timescales and conditions.This paper will concentrate on presenting a model testing scheme which both promotes transparency (for the sake of technical peer reviewers and the general public alike) and which aims at a thorough test of PA models. In addition, several recently published PAs will be critically examined and the form, extent and transparency of testing will be discussed with a view to improving confidence in the robustness of the models and thus the perceived safety of specific radwaste repository designs.

scholarly journals Basalt Glass: An Analogue for the Evaluation of the Long-Term Stability of Nuclear Waste form Borosilicate Glasses

1984 ◽  
Vol 44 ◽  
Author(s):  
C. D. Byers ◽  
M. J. Jercinovic ◽  
R. C. Ewing ◽  
K. Keil
Keyword(s):  
Nuclear Waste ◽  
Laboratory Data ◽  
Waste Form ◽  
Borosilicate Glasses ◽  
Term Stability ◽  
Long Term Stability ◽  
Basalt Glass ◽  
Time Periods ◽  
Basalt Glasses

AbstractThe long-term stability of nuclear waste form borosilicate glasses can be evaluated by understanding the processes that effect the long-term alteration of glass and by comparing laboratory alteration of synthetic basalt and borosilicate glasses with the observed stability of naturally occurring basaltic glasses in diverse geologic environments. This paper presents detailed electron microprobe analyses of naturally altered basaltic glasses (with maximum ages of 10,000 to 20 million years) from low-temperature environments. These results are compared to laboratory data on the corrosion of a synthetic basaltic glass in MCC-1 tests (90°C, a SA/V of 0.1 cm−1 and time periods up to 182 days), MCC-2 tests (190°C, a SA/V of 0.1 cm−1 and time periods up to 210 days) and hydration tests in saturated water vapor (240°C, an estimated SA/V of ∼ 106 cm−1 and time periods up to 63 days). Additionally, laboratory induced hydration alteration of synthetic basalt and borosilicate glasses is compared. These preliminary experiments provide evidence that the alteration processes observed for natural basalt glasses are relevant to understanding the alteration of nuclear waste glass, as both appear to react via similar processes.

(A review) Atlas of especially protected natural areas of Saint Petersburg / Ed. in chief V. N. Khramtsov, T. V. Kovaleva, N. Yu. Natsvaladze. St. Petersburg, 2013. 176 p.

2014 ◽  
pp. 124-129
Author(s):  
Z. V. Karamysheva
Keyword(s):  
Protected Areas ◽  
Large Scale ◽  
Natural Areas ◽  
Natural Protected Areas ◽  
Saint Petersburg ◽  
Natural Processes ◽  
Original Illustrations ◽  
Vegetation Maps ◽  
Protected Natural Areas

The review contains detailed description of the «Atlas of especially protected natural areas of Saint Petersburg» published in 2013. This publication presents the results of long-term studies of 12 natural protected areas made by a large research team in the years from 2002 to 2013 (see References). The Atlas contains a large number of the historical maps, new satellite images, the original illustrations, detailed texts on the nature of protected areas, summary tables of rare species of vascular plants, fungi and vertebrates recorded in these areas. Special attention is paid to the principles of thematic large-scale mapping. The landscape maps, the vegetation maps as well as the maps of natural processes in landscapes are included. Reviewed Atlas deserves the highest praise.

Enhancing community welfare through improved water quality: a case for applying staggered pollution charges in the river Musi sub-basin of Andhra Pradesh, India

Water Policy ◽  
2005 ◽  
Vol 7 (5) ◽  
pp. 469-483
Author(s):  
Tishya Chatterjee
Keyword(s):  
Andhra Pradesh ◽  
Relevant Literature ◽  
Pollution Prevention ◽  
Economic Benefits ◽  
Environmental Damage ◽  
Marginal Costs ◽  
Community Acceptance ◽  
Level Data ◽  
Over Time

In conditions of severe water-pollution and dormant community acceptance of accumulating environmental damage, the regulator's role goes beyond pollution prevention and more towards remediation and solutions based on the community's long-term expectations of economic benefits from clean water. This paper suggests a method to enable these benefits to become perceptible progressively, through participatory clean-up operations, supported by staggered pollution charges. It analyses the relevant literature on pollution prevention and applies a cost-based “willingness to pay” model, using primary basin-level data of total marginal costs. It develops a replicable demand-side approach imposing charge-standard targets over time in urban-industrial basins of developing countries.

The Short-Term and Long-Term Impacts of Sarbanes-Oxley Act on Composition and Characteristics of Corporate Board of Directors

2015 ◽  
Vol 5 (4) ◽  
Author(s):  
Halil Kaya ◽  
Gaurango Banerjee
Keyword(s):  
Board Composition ◽  
Corporate Boards ◽  
Corporate Accountability ◽  
Corporate Board ◽  
Short Term ◽  
Dual Roles ◽  
Board Characteristics ◽  
Sarbanes Oxley ◽  
Over Time

The paper examines the Sarbanes-Oxley (2002) Acts immediate impact on board composition and characteristics as well as possible reversals in its impact over time. Effects on directors age and tenure are analyzed over the 2001-06 sample period. Female participation in corporate boards is also studied in the pre-SOX and post-SOX periods. The dual roles of directors in being a member of the board as well as serving as either CEO, CFO, Chairman, Co-Chair, Founder, or Lead Director of their respective companies is also examined. We observe a short-term impact of SOX on board compositions due to changes seen in board characteristics between 2001 (pre-SOX), and 2003-05 short-term period (post-SOX). Also, we observe a reversal of board characteristics in 2006 to pre-SOX levels implying that the effects of SOX on board composition were short-lived, and needs to be monitored over time to ensure adherence to corporate accountability guidelines over the long-term.

A Downward Spiral? A Panel Study of Misinformation and Media Trust in Chile

2021 ◽  
pp. 194016122110252
Author(s):  
Sebastián Valenzuela ◽  
Daniel Halpern ◽  
Felipe Araneda
Keyword(s):  
News Media ◽  
Panel Study ◽  
Future Research ◽  
Panel Survey ◽  
Downward Spiral ◽  
The Media ◽  
Media Trust ◽  
People’S Attitudes ◽  
Over Time

Despite widespread concern, research on the consequences of misinformation on people's attitudes is surprisingly scant. To fill in this gap, the current study examines the long-term relationship between misinformation and trust in the news media. Based on the reinforcing spirals model, we analyzed data from a three-wave panel survey collected in Chile between 2017 and 2019. We found a weak, over-time relationship between misinformation and media skepticism. Specifically, initial beliefs on factually dubious information were negatively correlated with subsequent levels of trust in the news media. Lower trust in the media, in turn, was related over time to higher levels of misinformation. However, we found no evidence of a reverse, parallel process where media trust shielded users against misinformation, further reinforcing trust in the news media. The lack of evidence of a downward spiral suggests that the corrosive effects of misinformation on attitudes toward the news media are less serious than originally suggested. We close with a discussion of directions for future research.

scholarly journals Structured and Systematic Team and Procedure Training in Severe Trauma: Going from ‘Zero to Hero’ for a Time-Critical, Low-Volume Emergency Procedure Over Three Time Periods

2021 ◽  
Vol 45 (5) ◽  
pp. 1340-1348
Author(s):  
Maryam Meshkinfamfard ◽  
Jon Kristian Narvestad ◽  
Johannes Wiik Larsen ◽  
Arezo Kanani ◽  
Jørgen Vennesland ◽  
...  
Keyword(s):  
Injury Severity ◽  
Trauma System ◽  
Severe Trauma ◽  
Emergency Procedure ◽  
Emergency Thoracotomy ◽  
Severity Scores ◽  
Time Periods ◽  
Low Volume ◽  
Time Critical ◽  
Over Time

Abstract Background Resuscitative emergency thoracotomy is a potential life-saving procedure but is rarely performed outside of busy trauma centers. Yet the intervention cannot be deferred nor centralized for critically injured patients presenting in extremis. Low-volume experience may be mitigated by structured training. The aim of this study was to describe concurrent development of training and simulation in a trauma system and associated effect on one time-critical emergency procedure on patient outcome. Methods An observational cohort study split into 3 arbitrary time-phases of trauma system development referred to as ‘early’, ‘developing’ and ‘mature’ time-periods. Core characteristics of the system is described for each phase and concurrent outcomes for all consecutive emergency thoracotomies described with focus on patient characteristics and outcome analyzed for trends in time. Results Over the study period, a total of 36 emergency thoracotomies were performed, of which 5 survived (13.9%). The “early” phase had no survivors (0/10), with 2 of 13 (15%) and 3 of 13 (23%) surviving in the development and mature phase, respectively. A decline in ‘elderly’ (>55 years) patients who had emergency thoracotomy occurred with each time period (from 50%, 31% to 7.7%, respectively). The gender distribution and the injury severity scores on admission remained unchanged, while the rate of patients with signs on life (SOL) increased over time. Conclusion The improvement over time in survival for one time-critical emergency procedure may be attributed to structured implementation of team and procedure training. The findings may be transferred to other low-volume regions for improved trauma care.

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