scholarly journals A predictive model for the ichnological suitability of the Jezero crater, Mars: searching for fossilized traces of life-substrate interactions in the 2020 Rover Mission Landing Site

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11784
Author(s):  
Andrea Baucon ◽  
Carlos Neto de Carvalho ◽  
Antonino Briguglio ◽  
Michele Piazza ◽  
Fabrizio Felletti

Ichnofossils, the fossilized products of life-substrate interactions, are among the most abundant biosignatures on Earth and therefore they may provide scientific evidence of potential life that may have existed on Mars. Ichnofossils offer unique advantages in the search for extraterrestrial life, including the fact that they are resilient to processes that obliterate other evidence for past life, such as body fossils, as well as chemical and isotopic biosignatures. The goal of this paper is evaluating the suitability of the Mars 2020 Landing Site for ichnofossils. To this goal, we apply palaeontological predictive modelling, a technique used to forecast the location of fossil sites in uninvestigated areas on Earth. Accordingly, a geographic information system (GIS) of the landing site is developed. Each layer of the GIS maps the suitability for one or more ichnofossil types (bioturbation, bioerosion, biostratification structures) based on an assessment of a single attribute (suitability factor) of the Martian environment. Suitability criteria have been selected among the environmental attributes that control ichnofossil abundance and preservation in 18 reference sites on Earth. The goal of this research is delivered through three predictive maps showing which areas of the Mars 2020 Landing Site are more likely to preserve potential ichnofossils. On the basis of these maps, an ichnological strategy for the Perseverance rover is identified, indicating (1) 10 sites on Mars with high suitability for bioturbation, bioerosion and biostratification ichnofossils, (2) the ichnofossil types, if any, that are more likely to be present at each site, (3) the most efficient observation strategy for detecting eventual ichnofossils. The predictive maps and the ichnological strategy can be easily integrated in the existing plans for the exploration of the Jezero crater, realizing benefits in life-search efficiency and cost-reduction.

2021 ◽  
Author(s):  
Andrea Baucon ◽  
Carlos Neto De Carvalho ◽  
Antonino Briguglio ◽  
Fabrizio Felletti ◽  
Michele Piazza

<p>Seeking signs of past life in the geological record of Mars is one of the four primary goals of the NASA Mars 2020 mission. However, scant attention has been paid to the fossilized products of life-substrate interactions (ichnofossils), which are one of the most abundant and reliable biosignatures on Earth. This lack of attention is surprising because the ichnofossil heritage does not include only metazoan tracks, but also macroscopic burrows produced by bacteria, microborings ascribed to the activity of bacteria and fungi, and biostratification structures produced by archaea, cyanobacteria and euglenozoans. In light of this gap, the goal of the present study is evaluating the suitability of the Mars 2020 Landing Site for ichnofossils. To this goal, this work applies palaeontological predictive modelling, a technique used to predict the location of fossil sites in uninvestigated areas on Earth. Accordingly, a GIS of the landing site is developed. Each layer of the GIS maps the suitability for one or more ichnofossil types (bioturbation, bioerosion, biostratification structure) based on an assessment of a single attribute (suitability factor) of the Martian environment. Suitability criteria have been selected among the environmental attributes that control ichnofossil abundance, preservation, and accessibility in W Liguria (Italy), Naturtejo UNESCO Geopark (Portugal), and Ômnôgov district (Mongolia). The goal of this research will be delivered through a predictive map showing which areas of the Mars 2020 landing site are more likely to preserve ichnofossils. This map can be used to guide future efforts to the regions of the Mars 2020 Landing Site with the highest ichnological potential, realizing benefits in life-search efficiency and cost‐reduction.</p>


2020 ◽  
Vol 5 (1) ◽  
pp. 88-96
Author(s):  
Mary R. T. Kennedy

Purpose The purpose of this clinical focus article is to provide speech-language pathologists with a brief update of the evidence that provides possible explanations for our experiences while coaching college students with traumatic brain injury (TBI). Method The narrative text provides readers with lessons we learned as speech-language pathologists functioning as cognitive coaches to college students with TBI. This is not meant to be an exhaustive list, but rather to consider the recent scientific evidence that will help our understanding of how best to coach these college students. Conclusion Four lessons are described. Lesson 1 focuses on the value of self-reported responses to surveys, questionnaires, and interviews. Lesson 2 addresses the use of immediate/proximal goals as leverage for students to update their sense of self and how their abilities and disabilities may alter their more distal goals. Lesson 3 reminds us that teamwork is necessary to address the complex issues facing these students, which include their developmental stage, the sudden onset of trauma to the brain, and having to navigate going to college with a TBI. Lesson 4 focuses on the need for college students with TBI to learn how to self-advocate with instructors, family, and peers.


2017 ◽  
Vol 22 (4) ◽  
pp. 12-13
Author(s):  
LuAnn Haley ◽  
Marjorie Eskay-Auerbach

Abstract Pennsylvania adopted the impairment rating provisions described in the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) in 1996 as an exposure cap for employers seeking predictability and cost control in workers’ compensation claims. In 2017, the Supreme Court of Pennsylvania handed down the Protz decision, which held that requiring physicians to apply the methodology set forth in the most recent edition of the AMA Guides reflected an unconstitutional delegation of legislative power to the American Medical Association. The decision eliminates the impairment-rating evaluation (IRE) mechanism under which claimants were assigned an impairment rating under the most recent edition of the AMA Guides. The AMA Guides periodically are revised to include the most recent scientific evidence regarding impairment ratings, and the AMA Guides, Sixth Edition, acknowledges that impairment is a complex concept that is not yet defined in a way that readily permits an evidence-based definition of assessment. The AMA Guides should not be considered standards frozen in time simply to withstand future scrutiny by the courts; instead, workers’ compensation acts could state that when a new edition of the AMA Guides is published, the legislature shall review and consider adopting the new edition. It appears unlikely that the Protz decision will be followed in other jurisdictions: Challenges to using the AMA Guides in assessing workers’ compensation claims have been attempted in three states, and all attempts failed.


2004 ◽  
Vol 9 (2) ◽  
pp. 1-16
Author(s):  
Christopher R. Brigham ◽  
Kathryn Mueller ◽  
Douglas Van Zet ◽  
Debra J. Northrup ◽  
Edward B. Whitney ◽  
...  

Abstract [Continued from the January/February 2004 issue of The Guides Newsletter.] To understand discrepancies in reviewers’ ratings of impairments based on different editions of the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), users can usefully study the history of the revisions as successive editions attempted to provide a comprehensive, valid, reliable, unbiased, and evidence-based system. Some shortcomings of earlier editions have been addressed in the AMA Guides, Fifth Edition, but problems remain with each edition, largely because of the limited scientific evidence available. In the context of the history of the different editions of the AMA Guides and their development, the authors discuss and contextualize a number of key terms and principles including the following: definitions of impairment and normal; activities of daily living; maximum medical improvement; impairment percentages; conversion of regional impairments; combining impairments; pain and other subjective complaints; physician judgment; and causation analysis; finally, the authors note that impairment is not synonymous with disability or work interference. The AMA Guides, Fifth Edition, contrasts impairment evaluations and independent medical evaluations (this was not done in previous editions) and discusses impairment evaluations, rules for evaluations, and report standards. Upper extremity and lower extremity impairment evaluations are discussed in terms of clinical assessments and rating processes, analyzing important changes between editions and problematic areas (eg, complex regional pain syndrome).


2019 ◽  
Vol 89 (1-2) ◽  
pp. 80-88 ◽  
Author(s):  
Juliana Soares Severo ◽  
Jennifer Beatriz Silva Morais ◽  
Taynáh Emannuelle Coelho de Freitas ◽  
Ana Letícia Pereira Andrade ◽  
Mayara Monte Feitosa ◽  
...  

Abstract. Thyroid hormones play an important role in body homeostasis by facilitating metabolism of lipids and glucose, regulating metabolic adaptations, responding to changes in energy intake, and controlling thermogenesis. Proper metabolism and action of these hormones requires the participation of various nutrients. Among them is zinc, whose interaction with thyroid hormones is complex. It is known to regulate both the synthesis and mechanism of action of these hormones. In the present review, we aim to shed light on the regulatory effects of zinc on thyroid hormones. Scientific evidence shows that zinc plays a key role in the metabolism of thyroid hormones, specifically by regulating deiodinases enzymes activity, thyrotropin releasing hormone (TRH) and thyroid stimulating hormone (TSH) synthesis, as well as by modulating the structures of essential transcription factors involved in the synthesis of thyroid hormones. Serum concentrations of zinc also appear to influence the levels of serum T3, T4 and TSH. In addition, studies have shown that Zinc transporters (ZnTs) are present in the hypothalamus, pituitary and thyroid, but their functions remain unknown. Therefore, it is important to further investigate the roles of zinc in regulation of thyroid hormones metabolism, and their importance in the treatment of several diseases associated with thyroid gland dysfunction.


VASA ◽  
2010 ◽  
Vol 39 (2) ◽  
pp. 169-174 ◽  
Author(s):  
Reich-Schupke ◽  
Weyer ◽  
Altmeyer ◽  
Stücker

Background: Although foam sclerotherapy of varicose tributaries is common in daily practice, scientific evidence for the optimal sclerosant-concentration and session-frequency is still low. This study aimed to increase the knowledge on foam sclerotherapy of varicose tributaries and to evaluate the efficacy and safety of foam sclerotherapy with 0.5 % polidocanol in tributaries with 3-6 mm in diameter. Patients and methods: Analysis of 110 legs in 76 patients. Injections were given every second or third day. A maximum of 1 injection / leg and a volume of 2ml / injection were administered per session. Controls were performed approximately 6 months and 12 months after the start of therapy. Results: 110 legs (CEAP C2-C4) were followed up for a period of 14.2 ± 4.2 months. Reflux was eliminated after 3.4 ± 2.7 injections per leg. Insufficient tributaries were detected in 23.2 % after 6.2 ± 0.9 months and in 48.2 % after 14.2 ± 4.2 months, respectively. Only 30.9 % (34 / 110) of the legs required additional therapy. In 6.4 % vein surgery was performed, in 24.5 % similar sclerotherapy was repeated. Significantly fewer sclerotherapy-sessions were required compared to the initial treatment (mean: 2.3 ± 1.4, p = 0.0054). During the whole study period thrombophlebitis (8.2 %), hyperpigmentation (14.5 %), induration in the treated region (9.1 %), pain in the treated leg (7.3 %) and migraine (0.9 %) occurred. One patient with a history of thrombosis developed thrombosis of a muscle vein (0.9 %). After one year there were just hyperpigmentation (8.2 %) and induration (1.8 %) left. No severe adverse effect occurred. Conclusions: Foam sclerotherapy with injections of 0.5 % polidocanol every 2nd or 3rd day, is a safe procedure for varicose tributaries. The evaluation of efficacy is difficult, as it can hardly be said whether the detected tributaries in the controls are recurrent veins or have recently developed in the follow-up period. The low number of retreated legs indicates a high efficacy and satisfaction of the patients.


2010 ◽  
Vol 15 (3) ◽  
pp. 220-228 ◽  
Author(s):  
Viren Swami ◽  
Tomas Chamorro-Premuzic ◽  
Manal Shafi

Previous work has shown that is important to consider the disjunction between paranormal and nonparanormal beliefs about extraterrestrial life. The current study examined the association between both such beliefs and individual difference and demographic variables. A total of 555 British participants completed the Extraterrestrial Beliefs Scale, as well as measures of their Big Five personality scores, social conformity, sensation seeking, and demographics. Results showed no sex differences in ratings of paranormal and nonparanormal extraterrestrial beliefs, but participants rated nonparanormal beliefs more positively than paranormal beliefs. Results of structural equation modeling showed that individual difference factors (specifically, Openness, Conscientiousness, and social conformity) explained 21% of the variance in extraterrestrial beliefs, whereas demographic factors (specifically, education level, political orientation, and religiosity) explained 16% of the variance. Limitations and directions for future work are considered.


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