4,008 research outputs found
EVLA Observations of OH Masers in ON 1
This Letter reports on initial Expanded Very Large Array (EVLA) observations
of the 6035 MHz masers in ON 1. The EVLA data are of good quality, lending
confidence in the new receiver system. Nineteen maser features, including six
Zeeman pairs, are detected. The overall distribution of 6035 MHz OH masers is
similar to that of the 1665 MHz OH masers. The spatial resolution is sufficient
to unambiguously determine that the magnetic field is strong (~ -10 mG) at the
location of the blueshifted masers in the north, consistent with Zeeman
splitting detected in 13441 MHz OH masers in the same velocity range. Left and
right circularly polarized ground-state features dominate in different regions
in the north of the source, which may be due to a combination of magnetic field
and velocity gradients. The combined distribution of all OH masers toward the
south is suggestive of a shock structure of the sort previously seen in W3(OH).Comment: 4 pages using emulateapj.cls including 2 tables and 2 color figure
Aberrational Effects for Shadows of Black Holes
In this paper, we discuss how the shadow of a Kerr black hole depends on the
motion of the observer. In particular, we derive an analytical formula for the
boundary curve of the shadow for an observer moving with given four-velocity at
given Boyer--Lindquist coordinates. We visualize the shadow for various values
of parameters.Comment: 12 pages, 3 figures; Proceedings of the 524. WE-Heraeus-Seminar held
at the Physikzentrum, Bad Honnef, Germany, 17.--23.2.201
A combinatorial approach to knot recognition
This is a report on our ongoing research on a combinatorial approach to knot
recognition, using coloring of knots by certain algebraic objects called
quandles. The aim of the paper is to summarize the mathematical theory of knot
coloring in a compact, accessible manner, and to show how to use it for
computational purposes. In particular, we address how to determine colorability
of a knot, and propose to use SAT solving to search for colorings. The
computational complexity of the problem, both in theory and in our
implementation, is discussed. In the last part, we explain how coloring can be
utilized in knot recognition
Effelsberg Observations of Excited-State (6.0 GHz) OH in Supernova Remnants and W3(OH)
While masers in the 1720 MHz transition of OH are detected toward many
supernova remnants (SNRs), no other OH transition is seen as a maser in SNRs.
We present a search for masers at 6049 MHz, which has recently been predicted
to produce masers by pure collisional excitation at conditions similar to that
required for 1720 MHz masing. The Effelsberg 100 m telescope was used to
observe the excited-state 6016, 6030, 6035, and 6049 MHz lines of OH toward
selected SNRs, most of which have previously-detected bright 1720 MHz masers.
No excited-state masers are found toward SNRs, consistent with previous
observations of the 6049 MHz and other excited-state transitions. We do not see
clear evidence of absorption toward SNR target positions, although we do see
evidence of absorption in the molecular cloud at +50 km/s near Sgr A East. Weak
absorption is detected at 6016 MHz toward W3(OH), while stronger, narrower
emission is seen at 6049 MHz, suggesting that the 6049 MHz emission is a
low-gain maser. We conclude that conditions in SNRs are not conducive to
excited-state maser emission, especially in excited-state satellite lines.Comment: 4 pages using emulateapj.cls including 2 tables and 1 figure,
accepted to ApJ
Interpretation and the Constraints on International Courts
This paper argues that methodologies of interpretation do not do what they promise â they do not constrain interpretation by providing neutral steps that one can follow in finding out a meaning of a text â but nevertheless do their constraining work by being part of what can be described as the legal practice
Experimental evaluation of receptor-ligand interactions of dual-targeted particles to inflamed endothelium
Vascular-targeted carriers (VTCs) are often designed as leukocyte mimics, conjugated with ligands that target leukocyte adhesion molecules (LAMs) to facilitate specific adhesion to diseased endothelium. VTCs must adhere in regions with dynamic blood flow, frequently requiring multiple ligand-receptor (LR) pairs to provide particle adhesion and high disease specificity. To study LR kinetics under flow, multiple research groups have used protein-coated plates to study the adhesion and rolling of dual-targeted particles in vitro.1-4 While important knowledge is contributed by these studies, they lack the complexity of a diseased physiologic endothelium, as spatiotemporal LAM expression varies widely. Despite decades of research with the ambition of mimicking leukocytes, the specificity of multiple LAM-targeted VTCs remains poorly understood, especially in physiological environments. More specifically, there is a lack of mechanistic understanding of how multiple ligands interact with biologically complex endothelial surfaces under dynamic in vivo environments.
Please click Additional Files below to see the full abstract
Predicting academic success in optometry school
Introduction: Predicting success in optometry school is a challenging task which involves evaluating many academic and non-academic qualities. This study aids in the process of selecting candidates who are likely to be successful in the challenging optometric curriculum.
Methods: Optometry Admission Test (OAT) scores, interview scores, and undergraduate and optometry grade point averages (GPA) were gathered for 175 students admitted to Pacific University College of Optometry in 2001 and 2002. At-test compared characteristics of students who failed at least one didactic course in optometry school with students who passed all optometry courses. Regression analysis was then used to establish equations to predict academic performance.
Results and Discussion: All undergraduate GPA variables and most OAT subsections demonstrated a significant difference between students who failed an optometry course and those who did not. Reading Comprehension OAT, Physics OAT, and the interview score did not demonstrate a statistically significant difference between the two groups. Three equations were developed to help predict GPA in optometry school and to predict the probability of a student failing an optometric course.
Conclusion: The equations discussed can be used by admission committees as one tool to help in the application process and to predict success prior to admitting optometlic students
Evaluation of receptorâ ligand mechanisms of dualâ targeted particles to an inflamed endothelium
Vascularâ targeted carriers (VTCs) are designed as leukocyte mimics, decorated with ligands that target leukocyte adhesion molecules (LAMs) and facilitate adhesion to diseased endothelium. VTCs require different design considerations than other targeted particle therapies; adhesion of VTCs in regions with dynamic blood flow requires multiple ligandâ receptor (LR) pairs that provide particle adhesion and disease specificity. Despite the ultimate goal of leukocyte mimicry, the specificity of multiple LAMâ targeted VTCs remains poorly understood, especially in physiological environments. Here, we investigate particle binding to an inflamed mesentery via intravital microscopy using a series of particles with wellâ controlled ligand properties. We find that the total number of sites of a single ligand can drive particle adhesion to the endothelium, however, combining ligands that target multiple LR pairs provides a more effective approach. Combining sites of sialyl Lewis A (sLeA) and antiâ intercellular adhesion moleculeâ 1 (aICAM), two adhesive molecules, resulted in ⠟3â 7â fold increase of adherent particles at the endothelium over singleâ ligand particles. At a constant total ligand density, a particle with a ratio of 75% sLeA: 25% aICAM resulted in more than 3â fold increase over all over other ligand ratios tested in our in vivo model. Combined with in vivo and in silico data, we find the best dualâ ligand design of a particle is heavily dependent on the surface expression of the endothelial cells, producing superior adhesion with more particle ligand for the lesserâ expressed receptor. These results establish the importance of considering LRâ kinetics in intelligent VTC ligand design for future therapeutics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/133573/1/btm210008-sup-0007-suppinfo07.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/133573/2/btm210008_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/133573/3/btm210008.pd
- âŚ