Sobolev tests of goodness of fit of distributions on compact Riemannian manifolds

Classes of coordinate-invariant omnibus goodness-of-fit tests on compact Riemannian manifolds are proposed. The tests are based on Gin\'{e}'s Sobolev tests of uniformity. A condition for consistency is given. The tests are illustrated by an example on the rotation group $\mathit{SO}(3)$.Comment: Published at http://dx.doi.org/10.1214/009053605000000697 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

Classification of certain 6-manifolds

In (13) Wall classified up to diffeomorphism, PL-homeomorphism, topological homeomorphism, and homotopy equivalence all closed, oriented, 1-connected smooth (or PL) 6-manifolds with torsion-free homology and vanishing second Stiefel-Whitney class. This paper extends these classifications to all closed, oriented, 1-connected topological 6-manifolds with torsion-free homology. The method differs from that of (13) but uses two special cases of Wall's classificatio

Interview of Christine Sleeter on Multicultural Education: Past, Present, and Key Future Directions

This is an interview of Christine Sleeter on her work in multicultural education over four decades. Links to videos of this interview are available in the Appendix after the references. Transcriptions and videos of Dr. Sleeter’s interview provide plain-spoken content for teacher educators, school administrators, and teachers interested in advancing multicultural education and its critical and practical translation into public school classrooms. The main topics covered in this interview are: (a) the “origins” of multicultural education, (b) the basics of multicultural teaching in student and community relationships, (c) advice for new teachers coming into the profession, (d) discussions of White racism and what White teachers can do, and (e) the new social movement on ethnic studies curriculum. Broadly speaking, this interview provides a plain-spoken account of multicultural education’s past, present, and key future directions from Christine Sleeter, one of the field’s founding and most committed members

The stimulus control of local enclosures and barriers over head direction and place cell spatial firing

This research was supported by a grant to P.A.D. and E.R.W. from the Biotechnology and Biological Sciences Research Council (BB/P002455/1).Objective: Head direction cell and place cell spatially tuned firing is often anchored to salient visual landmarks on the periphery of a recording environment. What is less well understood is whether structural features of an environment, such as orientation of a maze sub-compartment or a polarising barrier, can likewise control spatial firing. Method: We recorded from 54 head direction cells in the medial entorhinal cortex and subicular region of male Lister Hooded rats while they explored an apparatus with four parallel or four radially-arranged compartments (Experiment 1). In Experiment 2, we recorded from 130 place cells (in Lister- and Long-Evans Hooded rats) and 30 head direction cells with 90° rotations of a cue card and a barrier in a single environment (Experiment 2). Results: We found that head direction cells maintained a similar preferred firing direction across four separate maze compartments even when these faced different directions (Experiment 1). However, in an environment with a single compartment, we observed that both a barrier and a cue card exerted comparable amounts of stimulus control over head direction cells and place cells (Experiment 2). Conclusion: The maintenance of a stable directional orientation across maze compartments suggests that the head direction cell system has the capacity to provide a global directional reference that allows the animal to distinguish otherwise similar maze compartments based on the compartment’s orientation. A barrier is, however, capable of controlling spatially tuned firing in an environment in which it is the sole polarising feature.Publisher PDFPeer reviewe

How did they get here from there? Detecting changes of direction in terrestrial ranging

Efficient exploitation of large-scale space is crucial to many species of animal, but the difficulties of studying how animals decide on travel routes in natural environments have hampered scientific understanding of environmental cognition. Field experiments allow researchers to define travel goals for their subjects, but practical difficulties restrict large-scale studies. In contrast, data on natural travel patterns are abundant and easy to record, but hard to interpret without circularity and subjectivity when making inferences about when and why an animal began heading to a particular location. We present a method of determining objectively the point at which an animal’s travel path becomes directed at a location, for instance a distant feeding site, based on the statistical characteristics of its route. We evaluate this method and illustrate how it can be tailored to particular problems, using data that is (a) synthetic; (b) from baboons, where travel is from a single sleeping site in an overlapping home range, and (c) from chimpanzees, where sleeping sites are unlimited within a large territory. We suggest that this ‘change- point test’ might usefully become a routine first step in interpreting the decision- making behind animal travel under natural conditions

Synthesis and Reactivity of the [NCCCO]⁻ Cyanoketenate Anion

Cyanoketene is a fundamental molecule that is actively being searched for in the interstellar medium. Its deprotonated form (cyanoketenate) is a heterocumulene that is isoelectronic to carbon suboxide whose structure has been the subject of debate. However, the investigation of cyanoketene and its derivatives is hampered by the lack of practical synthetic routes to these compounds. We report the first synthesis of the cyanoketenate anion in [K(18‐crown‐6)][NCCCO] (1) as a stable molecule on a multigram scale in excellent yields (>90 %). The structure of this molecule is probed crystallographically and computationally. We also explore the protonation of 1, and its reaction with triphenylsilylchloride and carbon dioxide. In all cases, anionic dimers are formed. The cyanoketene could be synthesized and crystallographically characterized when stabilized by a N‐heterocyclic carbene. The cyanoketenate is a very useful unsaturated building block containing N, C and O atoms that can now be explored with relative ease and will undoubtedly unlock more interesting reactivity

Synthesis and Reactivity of the [NCCCO]⁻ Cyanoketenate Anion

Cyanoketene is a fundamental molecule that is actively being searched for in the interstellar medium. Its deprotonated form (cyanoketenate) is a heterocumulene that is isoelectronic to carbon suboxide whose structure has been the subject of debate. However, the investigation of cyanoketene and its derivatives is hampered by the lack of practical synthetic routes to these compounds. We report the first synthesis of the cyanoketenate anion in [K(18‐crown‐6)][NCCCO] (1) as a stable molecule on a multigram scale in excellent yields (>90 %). The structure of this molecule is probed crystallographically and computationally. We also explore the protonation of 1, and its reaction with triphenylsilylchloride and carbon dioxide. In all cases, anionic dimers are formed. The cyanoketene could be synthesized and crystallographically characterized when stabilized by a N‐heterocyclic carbene. The cyanoketenate is a very useful unsaturated building block containing N, C and O atoms that can now be explored with relative ease and will undoubtedly unlock more interesting reactivity

Medijska pismenost – preduvjet za odgovorne medije: zbornik radova s 5. regionalne znanstvene konferencije Vjerodostojnost medija, ur. Viktorija Car, Lejla Turčilo, Marijana Matović. Sarajevo: Fakultet političkih nauka, 2015., 150 str.

The orientation of a rigid object can be described by a rotation that transforms it into a standard position. For a symmetrical object the rotation is known only up to multiplication by an element of the symmetry group. Such ambiguous rotations arise in biomechanics, crystallography and seismology. We develop methods for analyzing data of this form. A test of uniformity is given. Parametric models for ambiguous rotations are presented, tests of location are considered, and a regression model is proposed. An example involving orientations of diopside crystals (which have symmetry of order 2) is used throughout to illustrate how our methods can be applied.PostprintPeer reviewe