Redescription, paleogeography, and experimental paleoecology of the Silurian phyllocarid Gonatocaris

2020 ◽  
Vol 94 (5) ◽  
pp. 906-921
Author(s):  
Joseph H. Collette ◽  
Roy E. Plotnick

AbstractGonatocaris decora (Clarke, 1901) is an unusual, highly ornamented Silurian phyllocarid from the Pittsford Shale Member of the Vernon Formation, Salina Group of New York, that has been allied with Emmelezoe in the past due to the possession of an ‘optic tubercle.’ The systematic positions of Gonatocaris and Emmelezoe have been difficult to assess due to the lack of complete remains, attributions based on spurious characters, and missing and unfigured specimens. Relatively recent collections of Gonatocaris decora, along with a relocation of the original type material of Emmelezoe, have allowed a reexamination of all relevant genera and a more robust systematic placement for G. decora. Characters of generic importance for Gonatocaris include a greatly elongated abdomen; an acute angle of the ventral carapace margin separating distinct anteroventral and posteroventral margins from each other; and distinctive, multiscale horizontal ridge-like ornament of the carapace valves. Growth was found to be isometric. Experimental work done using a model of the scale-like ornament and multiple grain sizes of substrate indicates that cuticle ornament may have served to increase friction between the animal and a fine sand substrate, although resistance to predation is the currently favored hypothesis. Because Gonatocaris species are currently known only from the eastern margin of Laurentia and northern South China, it is likely that this genus was nektonic. Accumulations of similarly sized carapaces and other disarticulated sclerites in shallow-water settings may indicate spawning events following molting en masse.

2016 ◽  
Vol 69 (4) ◽  
pp. 57-64
Author(s):  
Genevieve Yue

Genevieve Yue interviews playwright Annie Baker, whose Pulitzer Prize–winning play The Flick focuses on the young employees of a single-screen New England movie house. Baker is one of the most critically lauded playwrights to emerge on the New York theater scene in the past ten years, in part due to her uncompromising commitment to experimentation and disruption. Baker intrinsically understands that arriving at something meaningful means taking a new way. Accordingly, Baker did not want to conduct a traditional interview for Film Quarterly. After running into each other at a New York Film Festival screening of Chantal Akerman's No Home Movie (2015)—both overwhelmed by the film—Yue and Baker agreed to begin their conversation by choosing a film neither of them had seen before and watching it together. The selection process itself led to a long discussion, which led to another, and then finally, to the Gmail hangout that forms the basis of the interview.


1988 ◽  
Vol 27 (1) ◽  
pp. 81-83
Author(s):  
Nadeem A. Burney

Its been long recognized that various economies of the world are interlinked through international trade. The experience of the past several years, however, has demonstrated that this economic interdependence is far greater than was previously realized. In this context, the importance of international economic theory as an area distinct from general economics hardly needs any mentioning. What gives international economic theory this distinction is international markets for some goods and effects of national sovereignty on the character of economic activity. Wilfred Ethier's book, which incorporates recent developments in the field, is an excellent addition to textbooks on international economics for one- or twosemester undergraduate courses. The book mostly covers standard topics. A distinguishing feature of this book is its detailed analysis of the flexible exchange rates and a discussion of the various approaches used for their determination. Within each chapter, the author has extensively used facts, figures and major events to clarify the concepts in the light of the theoretical framework. The book also discusses, in a fair amount of detail, the existing international monetary system and the role of various international organizations.


2019 ◽  
Author(s):  
Adib Rifqi Setiawan

Lisa Randall is a theoretical physicist working in particle physics and cosmology. She was born in Queens, New York City, on June 18, 1962. Lisa Randall is an alumna of Hampshire College Summer Studies in Mathematics; and she graduated from Stuyvesant High School in 1980. She won first place in the 1980 Westinghouse Science Talent Search at the age of 18; and at Harvard University, Lisa Randall earned both a BA in physics (1983) and a PhD in theoretical particle physics (1987) under advisor Howard Mason Georgi III, a theoretical physicist. She is currently Frank B. Baird, Jr. Professor of Science on the physics faculty of Harvard University, where he has been for the past a decade. Her works concerns elementary particles and fundamental forces, and has involved the study of a wide variety of models, the most recent involving dimensions. She has also worked on supersymmetry, Standard Model observables, cosmological inflation, baryogenesis, grand unified theories, and general relativity. Consequently, her studies have made her among the most cited and influential theoretical physicists and she has received numerous awards and honors for her scientific endeavors. Since December 27, 2010 at 00:42 (GMT+7), Lisa Randall is Twitter’s user with account @lirarandall. “Thanks to new followers. Interesting how different it feels broadcasting on line vs.via book or article. Explanations? Pithiness? Rapidity?” is her first tweet.


1970 ◽  
Vol 2 (3) ◽  
pp. 17-19 ◽  
Author(s):  
Jack D Ives

Preview of Himalayan perceptions: Environmental change and the well-being of mountain peoples by JD Ives Routledge, London and New York To be published in August 2004 Himalayan Perspectives returns to the enormously popular development paradigm that Ives dubbed the ‘Theory of Himalayan Degradation’. According to this seductive construct, poverty and overpopulation in the Himalayas was leading to degradation of highland forests, erosion, and downstream flooding. In the ‘Himalayan Dilemma’, Ives and Messerli exposed this “Theory” as a dangerous collection of assumptions and misrepresentations. While most scholars in the field promptly conceded Ives and Messerli’s points, the Theory has somehow survived as the guiding myth of development planners and many government agencies. In his new book, Ives returns to drive a stake through the heart of this revenant. His book not only reviews the research that, over the past 15 years, has confirmed the arguments of the ‘Himalayan Dilemma’; it also takes a close look at all those destructive factors that were overlooked by the conveniently simplistic ‘Theory of Himalayan Environmental Degradation’: government mismanagement, oppression of mountain minorities, armed conflict, and inappropriate tourism development. Himalayan Journal of Sciences 2(3): 17-19, 2004 The full text is of this article is available at the Himalayan Journal of Sciences website


2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Ronald G. Knapp

AbstractAmerica’s first documented wooden covered bridge was erected at Philadelphia, Pennsylvania in 1805. Hundreds were constructed within two decades and at least 10,000 by the later 1800s. As settlers moved West, broad rivers were crossed with inventive structures incorporating timber trusses ingeniously developed by carpenters. Called covered bridges because of the roof and siding needed to protect the timber trusses, they became ubiquitous features on the American landscape. Over the past two centuries, most covered bridges were lost to flood, ice, arson, lightening, decay, as well as “progress,” replaced by “modern” iron, concrete, and steel spans. Of some 700 covered bridges remaining, many are mere replicas of their original forms no longer supported by timber trusses. Genuine historic bridges remain largely from the last half of the 1800s while civic boosterism has led to claims of earlier dates with often questionable authenticity. This essay presents three wooden covered bridges constructed in the 1820s along a 10-mile stretch of the Wallkill River in New Paltz, New York. Of the three, only Perrine’s Bridge, constructed first in 1821 and covered in 1822, is still standing with intact Burr timber trusses. Perrine’s is an iconic structure with exceptional heritage value because of authentic re-building and restoration in 1834, 1846, 1917, and 1968. Using documentary records, this essay establishes an accurate intertwined chronology for the three bridges, detailing nineteenth century building practices and contentious mid-twentieth century struggles pitting preservationists wanting authentic restoration against those wanting removal.


1997 ◽  
Vol 48 (8) ◽  
pp. 923 ◽  
Author(s):  
Jiro Kittaka

The method developed over the past decade in northern Japan to culture phyllosoma larvae of five species of principally cool-temperate spiny lobsters combines the features of upwelling water, co- cultured microalgae, and use of mussel gonad as food. The feeding behaviour of the phyllosomas shows that they are primarily predators with the pereiopods and secondarily plankton feeders with the maxillipeds and maxillae. Recent work has shown that contamination of culture water by microorganisms such as the fouling protozoans Vorticellaspp. can greatly reduce phyllosoma survival. The significance of co-cultures of microalgae in maintaining water quality is not yet fully understood. Newly hatched lavae of sailfin sandfish (Arctoscopus japonicus) is an excellent food for late-stage phyllosomas of Jasus verreauxi. About 5% of J. verreauxi phyllosomas metamorphosed into pueruli. Mortality during the puerulus stage was reduced by increasing the capacity of the culture tanks from 30 L to 100 L. A single Palinurus elephas phyllosoma raised in co-culture with diatoms and fed mussel gonad and A. japonicus larvae metamorphosed into a puerulus in 65 days after seven moults.


1959 ◽  
Vol 105 (438) ◽  
pp. 235-237 ◽  
Author(s):  
A. Harris

Much interest has been displayed in the past few years in the effect on human subjects of reduction, or as far as possible, abolition of sensory stimulation, so that virtual isolation from the environment is produced. Recent comprehensive reviews have appeared, dealing with experimental work (Solomon et al. 1957) and conditions arising incidentally in the course of various therapeutic procedures (Grünthal 1957), and it is therefore unnecessary to deal with the topic at length here.


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