scholarly journals History of the Terminal Cataclysm Paradigm: Epistemology of a Planetary Bombardment That Never (?) Happened

Geosciences ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 285 ◽  
Author(s):  
Hartmann
Keyword(s):  
Open Access ◽  
Test Case ◽  
Front Side ◽  
Dynamical Models ◽  
Impact Melt ◽  
Late Heavy Bombardment ◽  
New Directions ◽  
History Of ◽  
Impact Melts ◽  
Lunar Basins

This study examines the history of the paradigm concerning a lunar (or solar-systemwide)terminal cataclysm (also called “Late Heavy Bombardment” or LHB), a putative, brief spikein impacts at ~3.9 Ga ago, preceded by low impact rates. We examine origin of the ideas, why theywere accepted, and why the ideas are currently being seriously revised, if not abandoned. Thepaper is divided into the following sections:1. Overview of paradigm.2. Pre-Apollo views (1949-1969).3. Initial suggestions of cataclysm (ca. 1974).4. Ironies.5. Alternative suggestions, megaregolith evolution (1970s).6. Impact melt rocks “establish” cataclysm (1990).7. Imbrium redux (ca. 1998).8. Impact melt clasts (early 2000s).9. Dating of front-side lunar basins?10. Dynamical models “explain” the cataclysm (c. 2000s).11. Asteroids as a test case.12. Impact melts predating 4.0 Ga ago (ca. 2008-present.).13. Biological issues.14. Growing doubts (ca. 1994-2014).15. Evolving Dynamical Models (ca. 2001-present).16. Connections to lunar origin.17. Dismantling the paradigm (2015-2018).18. “Megaregolith Evolution Model” for explaining the data.19. Conclusions and new directions for future work.The author hopes that this open-access discussion may prove useful for classroom discussionsof how science moves forward through self-correction of hypotheses.

scholarly journals The Struggle Against Torture: Challenges, Assumptions and New Directions

2019 ◽  
Vol 11 (2) ◽  
pp. 324-333
Author(s):  
Tobias Kelly
Keyword(s):  
Human Rights ◽  
Multiple Forms ◽  
Marginalized Groups ◽  
Current State ◽  
New Directions ◽  
History Of ◽  
Emerging Themes ◽  
Short Essay ◽  
Forms Of Violence

Abstract This short essay offers a broad and necessarily incomplete review of the current state of the human rights struggle against torture and ill-treatment. It sketches four widespread assumptions in that struggle: 1) that torture is an issue of detention and interrogation; 2) that political or security detainees are archetypal victims of torture; 3) that legal reform is one of the best ways to fight torture; and 4) that human rights monitoring helps to stamp out violence. These four assumptions have all played an important role in the history of the human rights fight against torture, but also resulted in limitations in terms of the interventions that are used, the forms of violence that human rights practitioners respond to, and the types of survivors they seek to protect. Taken together, these four assumptions have created challenges for the human rights community in confronting the multiple forms of torture rooted in the deep and widespread inequality experienced by many poor and marginalized groups. The essay ends by pointing to some emerging themes in the fight against torture, such as a focus on inequality, extra-custodial violence, and the role of corruption.

scholarly journals Is there enough star formation in simulated protoclusters?

2020 ◽  
Vol 501 (2) ◽  
pp. 1803-1822
Author(s):  
Seunghwan Lim ◽  
Douglas Scott ◽  
Arif Babul ◽  
David J Barnes ◽  
Scott T Kay ◽  
...  
Keyword(s):  
Star Formation ◽  
Galaxy Formation ◽  
Star Formation History ◽  
Test Case ◽  
Numerical Resolution ◽  
Formation History ◽  
Order Of Magnitude ◽  
History Of ◽  
Hydrodynamical Simulations ◽  
Formation Efficiency

ABSTRACT As progenitors of the most massive objects, protoclusters are key to tracing the evolution and star formation history of the Universe, and are responsible for ${\gtrsim }\, 20$ per cent of the cosmic star formation at $z\, {\gt }\, 2$. Using a combination of state-of-the-art hydrodynamical simulations and empirical models, we show that current galaxy formation models do not produce enough star formation in protoclusters to match observations. We find that the star formation rates (SFRs) predicted from the models are an order of magnitude lower than what is seen in observations, despite the relatively good agreement found for their mass-accretion histories, specifically that they lie on an evolutionary path to become Coma-like clusters at $z\, {\simeq }\, 0$. Using a well-studied protocluster core at $z\, {=}\, 4.3$ as a test case, we find that star formation efficiency of protocluster galaxies is higher than predicted by the models. We show that a large part of the discrepancy can be attributed to a dependence of SFR on the numerical resolution of the simulations, with a roughly factor of 3 drop in SFR when the spatial resolution decreases by a factor of 4. We also present predictions up to $z\, {\simeq }\, 7$. Compared to lower redshifts, we find that centrals (the most massive member galaxies) are more distinct from the other galaxies, while protocluster galaxies are less distinct from field galaxies. All these results suggest that, as a rare and extreme population at high z, protoclusters can help constrain galaxy formation models tuned to match the average population at $z\, {\simeq }\, 0$.

scholarly journals “Liberating the Small Devils”: Red Guard Newspapers and Radical Publics, 1966–1968

2021 ◽  
Vol 246 ◽  
pp. 354-373
Author(s):  
Nicolai Volland
Keyword(s):  
Public Sphere ◽  
Cultural Revolution ◽  
Early Research ◽  
Test Case ◽  
The Public ◽  
The Press ◽  
History Of ◽  
Red Guard ◽  
And Function ◽  
Chinese Public

AbstractRed Guard newspapers and pamphlets (wenge xiaobao) were a key source for early research on the Cultural Revolution, but they have rarely been analysed in their own right. How did these publications regard their status and function within the larger information ecosystem of the People's Republic, and what is their role in the history of the modern Chinese public sphere? This article focuses on a particular subset of Red Guard papers, namely those published by radical groups within the PRC's press and publication system. These newspapers critiqued the pre-Cultural Revolution press and reflected upon the possible futures of a new, revolutionary Chinese press. Short-lived as these experiments were, they constitute a test case to re-examine the functioning of the public in a decidedly “uncivil” polity. Ultimately, they point to the ambiguous potential of the public for both consensus and conflict, liberation and repression, which characterizes the press in 20th-century China.

Dead-Ends and New Directions

2021 ◽  
Vol 15 (4) ◽  
pp. 327-347
Author(s):  
Jean Francesco A.L. Gomes
Keyword(s):  
Natural History ◽  
Scientific Theory ◽  
Good Science ◽  
Orthodox Christian ◽  
The Core ◽  
The Earth ◽  
New Directions ◽  
History Of ◽  
Evolutionary Science ◽  
Doctrine Of Creation

Abstract The aim of this article is to investigate how Abraham Kuyper and some late neo-Calvinists have addressed the doctrine of creation in light of the challenges posed by evolutionary scientific theory. I argue that most neo-Calvinists today, particularly scholars from the Vrije Universiteit Amsterdam (VU), continue Kuyper’s legacy by holding the core principles of a creationist worldview. Yet, they have taken a new direction by explaining the natural history of the earth in evolutionary terms. In my analysis, Kuyper’s heirs at the VU today offer judicious parameters to guide Christians in conversation with evolutionary science, precisely because of their high appreciation of good science and awareness of the nonnegotiable elements that make up the orthodox Christian narrative.

scholarly journals From text to intertext: Intertextuality as a paradigm for reading Matthew

2005 ◽  
Vol 61 (1/2) ◽  
Author(s):  
Stefan Alkier
Keyword(s):  
Internal Structure ◽  
Test Case ◽  
Essential Factor ◽  
History Of ◽  
Biblical Texts

In this article intertextuality is introduced as one important part of a theory of the semiotics of biblical texts. Intertextuality is an essential factor for the generation of the meanings of a text in the acts of the production and reception of a text. It opens the internal structure of a text with regard to its relations to other texts. The semiotic concept of intertextuality distinguishes three ways of intertextual readings: production-oriented intertextuality, reception-oriented intertextuality and experimental intertextuality. This wide but differentiated concept of intertextuality can serve as a theory and helpful method for investigations of the history of biblical texts as well as for reflected school lessons, sermons and poetics in today’s times. An intertextual reading of the first chapter of Matthew provides a test case of this semiotic concept of intertextuality.

The Projectile of the Lappajärvi Impact Crater

1980 ◽  
Vol 35 (2) ◽  
pp. 197-203 ◽  
Author(s):  
Elke Göbel ◽  
Uwe Reimold ◽  
Hildegard Baddenhausen ◽  
Herbert Palme
Keyword(s):  
Impact Crater ◽  
Carbonaceous Chondrite ◽  
Volatile Elements ◽  
Rich Phase ◽  
Impact Melt ◽  
Siderophile Elements ◽  
High Concentrations ◽  
Impact Melts

Abstract Two impact melt samples from the Lappajärvi crater (Scandinavia) are highly enriched in siderophile elements, such as Ir, Re, and Os. This indicates the presence of a meteoritic component. The simultaneous enrichments of Ni, Co, Cr, and Se suggest a chondritic projectile. Because of the relatively large indigenous contributions to Ni, Co, and Cr, it is not possible to distinguish between a normal and a carbonaceous chondrite. The high concentrations of relatively volatile elements could point towards a volatile-rich projectile.The two melt samples have high Re/Ir ratios compared to chondritic ratios. Enrichment of Re relative to Ir is very unusual in terrestrial impact melts. Loss of Re, because of volatilisation under oxidizing conditions or by weathering is frequently observed.The high Re/Ir ratios and the high abundances of relatively volatile elements either indicate the presence of a volatile rich phase or they characterize a type of meteorite, which has not been sampled. Some lunar highland rocks have a pattern of meteoritic elements rather similar to that observed for the Lappajärvi meteorite.The Lappajärvi crater is, after Rocheehouart, the second European crater where a significant amount of meteoritic component has been found.A melt sample from the Lake St. Martin crater (Manitoba), did not show any enrichment in meteoritic elements.

scholarly journals Using Fuzzy Logic in Test Case Prioritization for Regression Testing Programs with Assertions

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Ali M. Alakeel
Keyword(s):  
Fuzzy Logic ◽  
Regression Testing ◽  
Test Case ◽  
Test Cases ◽  
Test Case Prioritization ◽  
Software Developers ◽  
Novel Approach ◽  
History Of ◽  
Supporting Tool

Program assertions have been recognized as a supporting tool during software development, testing, and maintenance. Therefore, software developers place assertions within their code in positions that are considered to be error prone or that have the potential to lead to a software crash or failure. Similar to any other software, programs with assertions must be maintained. Depending on the type of modification applied to the modified program, assertions also might have to undergo some modifications. New assertions may also be introduced in the new version of the program, while some assertions can be kept the same. This paper presents a novel approach for test case prioritization during regression testing of programs that have assertions using fuzzy logic. The main objective of this approach is to prioritize the test cases according to their estimated potential in violating a given program assertion. To develop the proposed approach, we utilize fuzzy logic techniques to estimate the effectiveness of a given test case in violating an assertion based on the history of the test cases in previous testing operations. We have conducted a case study in which the proposed approach is applied to various programs, and the results are promising compared to untreated and randomly ordered test cases.

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