57 research outputs found
The generalized Robinson-Foulds metric
The Robinson-Foulds (RF) metric is arguably the most widely used measure of
phylogenetic tree similarity, despite its well-known shortcomings: For example,
moving a single taxon in a tree can result in a tree that has maximum distance
to the original one; but the two trees are identical if we remove the single
taxon. To this end, we propose a natural extension of the RF metric that does
not simply count identical clades but instead, also takes similar clades into
consideration. In contrast to previous approaches, our model requires the
matching between clades to respect the structure of the two trees, a property
that the classical RF metric exhibits, too. We show that computing this
generalized RF metric is, unfortunately, NP-hard. We then present a simple
Integer Linear Program for its computation, and evaluate it by an
all-against-all comparison of 100 trees from a benchmark data set. We find that
matchings that respect the tree structure differ significantly from those that
do not, underlining the importance of this natural condition.Comment: Peer-reviewed and presented as part of the 13th Workshop on
Algorithms in Bioinformatics (WABI2013
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The 'lost child' as figure of trauma and recovery in early post-war cinema: Fred Zinnemann's The Search (1948) and Natan Gross's Unzere Kinder (1948)
The article examines the figure of the ‘lost child’ in feature films of the immediate post-war period. The figure’s enormous symbolic value as innocent victim and future generation, granted the ‘lost child’ a key position in post-war discourse, including films which tried to grapple with the moral and physical destruction of the continent after 1945. National film industries, particularly of the perpetrator nation, employed the ‘lost child’ for genre stories in which the post-war chaos is being mastered and a new, masculine national self is re-built. However, films made by victim groups outside a national context rely on the ‘lost child’ to broach the destruction of their identity by war and persecution. Analysing two films, Fred Zinnemann’s The Search (1948) and Nata Gross’s Unzere Kinder (1948), I argue that they use the child figure to deal with traumatization and make it part of the reconstruction of communal intergenerational relations. This does not result in stories of masculine mastery but in narratives that incorporate moments of trauma process emerging around destroyed mother-child relations. The films, encoding traumatization in film language, develop a rich cinematic language along questions of identity and form a first instance of posttraumatic cinema
A New Troodontid Theropod, Talos sampsoni gen. et sp. nov., from the Upper Cretaceous Western Interior Basin of North America
Troodontids are a predominantly small-bodied group of feathered theropod dinosaurs notable for their close evolutionary relationship with Avialae. Despite a diverse Asian representation with remarkable growth in recent years, the North American record of the clade remains poor, with only one controversial species--Troodon formosus--presently known from substantial skeletal remains.Here we report a gracile new troodontid theropod--Talos sampsoni gen. et sp. nov.--from the Upper Cretaceous Kaiparowits Formation, Utah, USA, representing one of the most complete troodontid skeletons described from North America to date. Histological assessment of the holotype specimen indicates that the adult body size of Talos was notably smaller than that of the contemporary genus Troodon. Phylogenetic analysis recovers Talos as a member of a derived, latest Cretaceous subclade, minimally containing Troodon, Saurornithoides, and Zanabazar. MicroCT scans reveal extreme pathological remodeling on pedal phalanx II-1 of the holotype specimen likely resulting from physical trauma and subsequent infectious processes.Talos sampsoni adds to the singularity of the Kaiparowits Formation dinosaur fauna, which is represented by at least 10 previously unrecognized species including the recently named ceratopsids Utahceratops and Kosmoceratops, the hadrosaurine Gryposaurus monumentensis, the tyrannosaurid Teratophoneus, and the oviraptorosaurian Hagryphus. The presence of a distinct troodontid taxon in the Kaiparowits Formation supports the hypothesis that late Campanian dinosaurs of the Western Interior Basin exhibited restricted geographic ranges and suggests that the taxonomic diversity of Late Cretaceous troodontids from North America is currently underestimated. An apparent traumatic injury to the foot of Talos with evidence of subsequent healing sheds new light on the paleobiology of deinonychosaurians by bolstering functional interpretations of prey grappling and/or intraspecific combat for the second pedal digit, and supporting trackway evidence indicating a minimal role in weight bearing
Mount Edgcumbe
'MOUNT EDGCUMBE. DEVON. Drawn by J. D. Harding, from a sketch by Jendle. Engraved by E. Finden. London, Published for the Proprietors, by Geo. Virtue, 26, Ivy Lane.' Immediately below centre of image is '29'
View from the beach at Sidmouth
'VIEW FROM THE BEACH AT SIDMOUTH. LOOKING TOWARDS THE SOUTH-WEST. Drawn by J. D. Harding, from a sketch by Jendle. Engraved by E. Finden. London; Published for the Proprietors by Geo. Virtue, 26, Ivy Lane.
Budleigh Salterton
'BUDLEIGH SALTERTON. Drawn by J. D. Harding from a sketch by - Jendle. Engraved by W. Finden. London; Published for the Proprietors, by Geo. Virtue, 26, Ivy Lane'
Plymouth, Devon
'PLYMOUTH, DEVON. Drawn by J. D. Harding from a sketch by - Jendle. Engraved by W. Finden. London, Published 1837, by Charles Tilt, 86, Fleet Street
Nazareth [Material gráfico]
Resumen: Descripción: vista de Nazareth. En primer término, rebaño de ovejas y personajes; al fondo, el poblado
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