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[Binder's Collection: A. Worrell]
No full textBound compilation of sheet music from the collection of Thurman Morrison, presumably compiled by Ann Worrell, whose name is inscribed on multiple works within the volume. The vast majority of titles in this collection were published in Philadelphia, and the remainder in Baltimore, between 1796 and 1830. A number of items have themes related to Scotland, along with several works about soldiers. Composers Michael Kelly, Joseph Mazinghi, John Stevenson, and Thomas H. Thompson are most prominent, with three works each, and Thomas Moore was the lyricist for four works. George Willig, G.E. Blake, and various iterations of the Carr publishing company are the most prominent publishers in this volume
On restricted nonnegative matrix factorization
No full textNonnegative matrix factorization (NMF) is the problem of decomposing a given nonnegative n × m matrix M into a product of a nonnegative n × d matrix W and a nonnegative d × m matrix H. Restricted NMF requires in addition that the column spaces of M and W coincide. Finding the minimal inner dimension d is known to be NP-hard, both for NMF and restricted NMF. We show that restricted NMF is closely related to a question about the nature of minimal probabilistic automata, posed by Paz in his seminal 1971 textbook. We use this connection to answer Paz’s question negatively, thus falsifying a positive answer claimed in 1974. Furthermore, we investigate whether a rational matrix M always has a restricted NMF of minimal inner dimension whose factors W and H are also rational. We show that this holds for matrices M of rank at most 3 and we exhibit a rank-4 matrix for which W and H require irrational entries
On LTL Model Checking for Low-Dimensional Discrete Linear Dynamical Systems
No full textConsider a discrete dynamical system given by a square matrix M ∈ ℚ^{d × d} and a starting point s ∈ ℚ^d. The orbit of such a system is the infinite trajectory ⟨ s, Ms, M²s, …⟩. Given a collection T₁, T₂, …, T_m ⊆ ℝ^d of semialgebraic sets, we can associate with each T_i an atomic proposition P_i which evaluates to true at time n if, and only if, M^ns ∈ T_i. This gives rise to the LTL Model-Checking Problem for discrete linear dynamical systems: given such a system (M,s) and an LTL formula over such atomic propositions, determine whether the orbit satisfies the formula. The main contribution of the present paper is to show that the LTL Model-Checking Problem for discrete linear dynamical systems is decidable in dimension 3 or less
New proofs of theorems of Michael and Worrell
No full textNew proofs of theorems of Michael and Worrell, that paracompactness and metacompactness are closed continuous invariants are presented here. A result due to Joseph and Kwack that all open sets in have the form , where is open in , if is continuous, closed and onto is used to give the new proofs.</jats:p
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
On Matrix Powering in Low Dimensions
No full textWe investigate the Matrix Powering Positivity Problem, PosMatPow: given an m X m square integer matrix M, a linear function f: Z^{m X m} -> Z with integer coefficients, and a positive integer n (encoded in binary), determine whether f(M^n) \geq 0. We show that for fixed dimensions m of 2 and 3, this problem is decidable in polynomial time
CSPG4 in osteosarcoma: functional roles and therapeutic potential
No full textOsteosarcoma is the most common primary malignancy of bone. 5-year survival has
remained stable at around 60-70% for 40 years. However, a number of patients will suffer
from recurrent and/or metastatic disease representing a large unmet clinical need. CSPG4 is
a transmembrane protein which is expressed on a number of progenitor cells and tumour
types. Preliminary work had found CSPG4 present in osteosarcoma tumour samples.
In this study, CSPG4 mRNA and protein expression was demonstrated in clinical samples and
model cell lines. CSPG4 mRNA is overexpressed in osteosarcoma samples compared to
mature osteoblast cells, the putative cell of origin for osteosarcoma. In a cohort of patients,
CSPG4 protein expression was found on 86% of samples. Furthermore, CSPG4 expression
was demonstrated in U2OS, MG63, HOS, HOS-MNNG and 143B osteosarcoma cell lines.
CSPG4 protein expression was successfully deleted in 143B cells using CRISPR/Cas9
technology. Two stable CSPG4-negative cell lines were produced. CSPG4 expression was
then reintroduced into negative cell lines, as well as the parental 143B cell line. This created
a panel of 6 cell lines with differing CSPG4 expression. Furthermore, siRNA treatment of
U2OS, MG63, 143B and U87MG cell lines reduced CSPG4 expression. These cells provided
another panel with varying CSPG4 expression for in vitro investigation.
In vitro experiments failed to demonstrate a role for CSPG4 in osteosarcoma tumorigenesis.
The CRISPR/Cas9 cell panel found that CSPG4 expression did not influence cell proliferation,
adhesion and spreading on fibronectin or collagen-I, cell migration, chemosensitivity or
anchorage-independent growth. Similarly, the siRNA cell panel found that CSPG4 expression
did not influence cell proliferation or anchorage-independent growth. In vivo
experimentation did not demonstrate a role for CSPG4 in mediating osteosarcoma tumour
growth or metastatic spread. Treatment with a sc-Fv antibody fragment failed to
demonstrate specific toxicity of CSPG4-positive cell lines.
These results indicate that CSPG4 plays no role in osteosarcoma tumour cell behaviour.
However, due to its wide expression pattern it represents a viable therapeutic option for
drug targeting
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Nonnegativity problems for matrix semigroups
No full textThe matrix semigroup membership problem asks, given square matrices M, M1, ..., Mk of the same dimension, whether M lies in the semigroup generated by M1, ..., Mk. It is classical that this problem is undecidable in general, but decidable in case M1, ..., Mk commute. In this paper we consider the problem of whether, given M1, ..., Mk, the semigroup generated by M1, ..., Mk contains a non-negative matrix. We show that in case M1, ..., Mk commute, this problem is decidable subject to Schanuel's Conjecture. We show also that the problem is undecidable if the commutativity assumption is dropped. A key lemma in our decidability proof is a procedure to determine, given a matrix M, whether the sequence of matrices (Mn)∞n=0 is ultimately nonnegative. This answers a problem posed by S. Akshay [1]. The latter result is in stark contrast to the notorious fact that it is not known how to determine, for any specific matrix index (i, j), whether the sequence (Mn)i,j is ultimately nonnegative. Indeed the latter is equivalent to the Ultimate Positivity Problem for linear recurrence sequences, a longstanding open problem
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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