731 research outputs found
Dendritic Spine Shape Analysis: A Clustering Perspective
Functional properties of neurons are strongly coupled with their morphology.
Changes in neuronal activity alter morphological characteristics of dendritic
spines. First step towards understanding the structure-function relationship is
to group spines into main spine classes reported in the literature. Shape
analysis of dendritic spines can help neuroscientists understand the underlying
relationships. Due to unavailability of reliable automated tools, this analysis
is currently performed manually which is a time-intensive and subjective task.
Several studies on spine shape classification have been reported in the
literature, however, there is an on-going debate on whether distinct spine
shape classes exist or whether spines should be modeled through a continuum of
shape variations. Another challenge is the subjectivity and bias that is
introduced due to the supervised nature of classification approaches. In this
paper, we aim to address these issues by presenting a clustering perspective.
In this context, clustering may serve both confirmation of known patterns and
discovery of new ones. We perform cluster analysis on two-photon microscopic
images of spines using morphological, shape, and appearance based features and
gain insights into the spine shape analysis problem. We use histogram of
oriented gradients (HOG), disjunctive normal shape models (DNSM), morphological
features, and intensity profile based features for cluster analysis. We use
x-means to perform cluster analysis that selects the number of clusters
automatically using the Bayesian information criterion (BIC). For all features,
this analysis produces 4 clusters and we observe the formation of at least one
cluster consisting of spines which are difficult to be assigned to a known
class. This observation supports the argument of intermediate shape types.Comment: Accepted for BioImageComputing workshop at ECCV 201
(Quantum) Space-Time as a Statistical Geometry of Fuzzy Lumps and the Connection with Random Metric Spaces
We develop a kind of pregeometry consisting of a web of overlapping fuzzy
lumps which interact with each other. The individual lumps are understood as
certain closely entangled subgraphs (cliques) in a dynamically evolving network
which, in a certain approximation, can be visualized as a time-dependent random
graph. This strand of ideas is merged with another one, deriving from ideas,
developed some time ago by Menger et al, that is, the concept of probabilistic-
or random metric spaces, representing a natural extension of the metrical
continuum into a more microscopic regime. It is our general goal to find a
better adapted geometric environment for the description of microphysics. In
this sense one may it also view as a dynamical randomisation of the causal-set
framework developed by e.g. Sorkin et al. In doing this we incorporate, as a
perhaps new aspect, various concepts from fuzzy set theory.Comment: 25 pages, Latex, no figures, some references added, some minor
changes added relating to previous wor
The Ursinus Weekly, April 17, 1970
Administration deals USGA policy slap • Earth Day planned April 22: Grass-roots pollution fight • 1970 UC Campus Chest attempts $3,000 goal • Youngbloods, MagMen appearing on April 23 • Editorial: Student Bill of Rights • Focus: Alice Johnson • Faculty portrait: Philip J. Rappoccio • Greener ginkgo trees • Contemplations: Bill of Rights • Committee report: UC Student Union • Chapter scholars named • From the other side: Heaven on earth? • Letters to the editor: Amico speaks; Arts Festival; Underground; Weekly; Student Union? • Bears battle Mules in season\u27s opener • Snell honored on May 22nd • Returning Bearettes bolster spring teams • U.C. netmen steal moral victory over Swarthmore • Bear trackmen whip everybody on cindershttps://digitalcommons.ursinus.edu/weekly/1158/thumbnail.jp
The Ursinus Weekly, March 19, 1970
New USGA studies dress code, rights • Campus Chest Committee selects student-faculty cast and chorus • Second Arts Festival considered successful • Senior class plans prom, graduation; Newman contacted • Girls basketball team captures third place in national competition • Editorial: Dress regulations • Focus: Vincent Scancella • Letters to the editor: Freak weekend; Lantern review; Inconsiderate students; Meal mess; Protheater thanks; Open dorm rule; Action line; Interest; Both sides now • Perspectives: The first victory • Dining Hall dishwashers enjoy most fun job • Opinion: A petty organization • Perusing the catalog • Cafeteria meals, open dorms proposed to aid Ursinus budget • Recruiting difficult, claim Bear coaches • Ted Taylor chosen as new coach • Freshman hoopster tops Bear scoring • Matmen end 1-9 campaign with hope for next seasonhttps://digitalcommons.ursinus.edu/weekly/1157/thumbnail.jp
Prospects for measuring the gravitational free-fall of antihydrogen with emulsion detectors
The main goal of the AEgIS experiment at CERN is to test the weak equivalence
principle for antimatter. AEgIS will measure the free-fall of an antihydrogen
beam traversing a moir\'e deflectometer. The goal is to determine the
gravitational acceleration g for antihydrogen with an initial relative accuracy
of 1% by using an emulsion detector combined with a silicon micro-strip
detector to measure the time of flight. Nuclear emulsions can measure the
annihilation vertex of antihydrogen atoms with a precision of about 1 - 2
microns r.m.s. We present here results for emulsion detectors operated in
vacuum using low energy antiprotons from the CERN antiproton decelerator. We
compare with Monte Carlo simulations, and discuss the impact on the AEgIS
project.Comment: 20 pages, 16 figures, 3 table
The development of accounting in UK universities:an oral history
This article reports on the development of the accounting discipline in universities in England and Scotland from the 1960s. Drawing on the oral history narratives of six distinguished accounting scholars who played a significant role in the discipline, this article documents (1) the initial influences on the teaching of accounting in English universities, (2) the different influences on the teaching of accounting in Scottish universities and (3) the influence of US universities and their scholars on the development of academic accounting in the United Kingdom. With a focus on the second wave of accounting professoriate who followed the London School of Economics (LSE) ‘Triumvirate’ of William Baxter, Harold Edey and David Solomons, this article provides first-hand insights into the shape and spread of university accounting education at a crucial stage of its development. This, in turn, develops an understanding of the contemporary academic accounting discipline in the United Kingdom.PostprintPeer reviewe
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