2,356 research outputs found
Entanglement of four qubit systems: a geometric atlas with polynomial compass I (the finite world)
We investigate the geometry of the four qubit systems by means of algebraic
geometry and invariant theory, which allows us to interpret certain entangled
states as algebraic varieties. More precisely we describe the nullcone, i.e.,
the set of states annihilated by all invariant polynomials, and also the so
called third secant variety, which can be interpreted as the generalization of
GHZ-states for more than three qubits. All our geometric descriptions go along
with algorithms which allow us to identify any given state in the nullcone or
in the third secant variety as a point of one of the 47 varieties described in
the paper. These 47 varieties correspond to 47 non-equivalent entanglement
patterns, which reduce to 15 different classes if we allow permutations of the
qubits.Comment: 48 pages, 7 tables, 13 figures, references and remarks added (v2
Seeking Symbiosis: Designing LibGuides that Bring User-Centered Design and Learner-Centered Practice into Harmony
Libraries around the world use LibGuides to create research guides for students. But is the user-centered approach often employed by libraries when creating these guides enough to meet the needs of today’s learners? A small task force of librarians at Oxford College of Emory University set out to answer this question. After studying the literature, it was found that very few studies focus on instructional design principles in the creation of LibGuides. Furthermore, an examination of their own library’s LibGuides revealed that while the guides addressed many issues of usability, learner-centered design was often absent.
(25 minutes) The first portion of the workshop will outline the efforts of the task force to create a LibGuide template for Oxford College’s new first-year seminar courses. The iterative design of the course guide template seeks to bring into symbiosis user-centered design and learner-centered practice. The goal of the template is to point students toward recommended resources and teach them valuable information literacy skills along the way. Results from the initial rollout and subsequent evaluation of the template will be presented.
(40 minutes) Attendees will then be divided into groups led by each of the presenters to share their libraries’ experiences in creating course guides. The groups will brainstorm ideas for how these teaching tools can better meet the learning needs of students. A laptop will be provided for each group so that attendees can evaluate their institution’s LibGuides. At the end of the workshop, each group will designate a speaker to present some of their group’s ideas (10 minutes)
The function of microRNAs in cartilage and osteoarthritis
MicroRNAs are small double-stranded RNAs, which negatively regulate gene expression and have been shown to have key roles in both chondrocyte development and cartilage homeostasis with age. Deletion of all microRNAs in chondrocytes leads to skeletal growth defects in mice, whilst deletion of specific mi croRNAs, e.g. miR-140, leads to premature articular cartilage degradation and increased susceptibility to posttraumatic osteoarthritis. Studies comparing microRNA expression in normal human articular cartilage compared to osteoarthritic cartilage show differential expression, but varying sample groups make interpretation difficult. MicroRNAs have been proposed as circulating biomarkers of osteoarthritis, but again, this differs amongst patient cohorts. Many micro- RNAs have been shown to have roles in chondrocyte phenotype via signaling pathways, apoptosis, autophagy and senescence. Modulating microRNAs in the joint has been shown to reduce osteoarthritis in animal models and translating this to man as a novel therapeutic strategy will be key
Recurrent Episodes of Acute Pancreatitis Present to the ED with More Severe Disease by CT than First-Time Acute Pancreatitis
Study Objective: Approximately 30% of patients with one episode of acute pancreatitis experience a recurrent episode. The objective of this study is to compare the severity of the first-time episode versus recurrent episodes of acute pancreatitis based on CT scan.
Methods: This study was conducted as part of a retrospective chart review at a single academic urban emergency department from 2012-2016. Criteria for inclusion included clinical symptoms of pancreatitis, age greater than or equal to 18 years, ED diagnosis of acute pancreatitis, and, an abdominal CT scan within 24 hours of triage. Exclusion criteria were traumatic cause of acute pancreatitis and pregnancy. Charts were reviewed by a trained abstractor using structured data collection sheets which included data elements such as a history of acute pancreatitis and the results of an abdominal CT scan. Data abstraction was confirmed for interrater reliability. CT Scans were graded using the Modified CT Severity Index (MCTSI) which grades acute pancreatitis by the presence of inflammation, fluid accumulation, necrosis or extra-pancreatic findings.
Results: 283 patients were included in the study. Of these, 110 patients resented with recurrent acute pancreatitis and 173 patients presented with first-time acute pancreatitis. We calculated the mean MCTSI score in both groups and found a significantly higher rate of severity in recurrent acute pancreatitis versus first episode (2.09 vs. 1.43, p\u3c0.05.)
Conclusion: Patients with recurrent acute pancreatitis are more likely to present with a more severe episode of acute pancreatitis than patients presenting with first-time acute pancreatitis
Algebraic invariants of five qubits
The Hilbert series of the algebra of polynomial invariants of pure states of
five qubits is obtained, and the simplest invariants are computed.Comment: 4 pages, revtex. Short discussion of quant-ph/0506073 include
Deflated GMRES for Systems with Multiple Shifts and Multiple Right-Hand Sides
We consider solution of multiply shifted systems of nonsymmetric linear
equations, possibly also with multiple right-hand sides. First, for a single
right-hand side, the matrix is shifted by several multiples of the identity.
Such problems arise in a number of applications, including lattice quantum
chromodynamics where the matrices are complex and non-Hermitian. Some Krylov
iterative methods such as GMRES and BiCGStab have been used to solve multiply
shifted systems for about the cost of solving just one system. Restarted GMRES
can be improved by deflating eigenvalues for matrices that have a few small
eigenvalues. We show that a particular deflated method, GMRES-DR, can be
applied to multiply shifted systems. In quantum chromodynamics, it is common to
have multiple right-hand sides with multiple shifts for each right-hand side.
We develop a method that efficiently solves the multiple right-hand sides by
using a deflated version of GMRES and yet keeps costs for all of the multiply
shifted systems close to those for one shift. An example is given showing this
can be extremely effective with a quantum chromodynamics matrix.Comment: 19 pages, 9 figure
Anti-proliferative Effects of Common Plant Extracts on Tumor Cells in Vitro
In 2018, the World Health Organization identified cancer as responsible for 1 in 6 deaths globally, encouraging the exploration of creative forms of cancer treatment. Our research interests include identifying anti-proliferative plant extracts and illuminating mechanisms of growth inhibition. In this study we measured the effects of Vitis vinifera (grapeseed), Juniperus communis (juniper berry), and Curcuma longa (turmeric) extracts on the proliferation of several normal and tumorigenic cell strains and lines (HFF-S2, HeLa, HepG2, MDA MB 231, and RAW 264.7). We performed dose response CyQUANT assays to analyze the effects on cell growth. We are using DNA analysis, recovery experiments, and DAPI staining to investigate whether our extracts induce apoptosis in these cells. Our results showed dose-dependent inhibition of cell growth in vitro with all three extracts but not with extracts from other plants. The results of this study suggest the potential for further study of components of grapeseed, juniper berry, and turmeric extracts as potential chemo preventive agents
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