8,355 research outputs found
Paul’s Use of Leviticus 19:18: A Comparative Analysis with Select Second Temple Jewish Texts
Paul’s use of Leviticus 19:18 in Romans 13:8-10 and Galatians 5:13-15 begs the question of how a command that is not repeated in the Old Testament came to the position of prominence as the summarizing and fulfilling statement of the whole law. This study aims to analyze select Second Temple Jewish texts and Paul’s letters to the Romans and Galatians in order to trace the uses of or allusions to Leviticus 19:18 and determine how Paul’s use of Leviticus 19:18 compares and differs from the selected texts. The Second Temple Jewish texts that are analyzed include the Testaments of the Twelve Patriarchs, Tobit 4:15, Bavli Shabbat 31a, the Damascus Document, and the Community Rule. The comparative analysis reveals that Paul’s use of Leviticus 19:18 in Romans 13:8-10 and Galatians 5:13-15 is shaped by the crucifixion of Jesus Christ and is thus unique when compared to preceding and contemporary Second Temple Jewish texts
Isostaticity at Frictional Jamming
Amorphous packings of frictionless, spherical particles are isostatic at
jamming onset, with the number of constraints (contacts) equal to the number of
degrees of freedom. Their structural and mechanical properties are controlled
by the interparticle contact network. In contrast, amorphous packings of
frictional particles are typically hyperstatic at jamming onset. We perform
extensive numerical simulations in two dimensions of the geometrical asperity
(GA) model for static friction, to further investigate the role of
isostaticity. In the GA model, interparticle forces are obtained by summing up
purely repulsive central forces between periodically spaced circular asperities
on contacting grains. We compare the packing fraction, contact number,
mobilization distribution, and vibrational density of states using the GA model
to those generated using the Cundall-Strack (CS) approach. We find that static
packings of frictional disks obtained from the GA model are mechanically stable
and isostatic when we consider interactions between asperities on contacting
particles. The crossover in the structural and mechanical properties of static
packings from frictionless to frictional behavior as a function of the static
friction coefficient coincides with a change in the type of interparticle
contacts and the disappearance of a peak in the density of vibrational modes
for the GA model. These results emphasize that mesoscale features of the model
for static friction play an important role in determining the properties of
granular packings.Comment: 4.5 pages, 5 figures, http://prl.aps.org/covers/110/1
Impact of surface-polish on the angular and wavelength dependence of fiber focal ratio degradation
We present measurements of how multimode fiber focal-ratio degradation (FRD)
and throughput vary with levels of fiber surface polish from 60 to 0.5 micron
grit. Measurements used full-beam and laser injection methods at wavelengths
between 0.4 and 0.8 microns on 17 meter lengths of Polymicro FBP 300 and 400
micron core fiber. Full-beam injection probed input focal-ratios between f/3
and f/13.5, while laser injection allowed us to isolate FRD at discrete
injection angles up to 17 degrees (f/1.6 marginal ray). We find (1) FRD effects
decrease as grit size decreases, with the largest gains in beam quality
occurring at grit sizes above 5 microns; (2) total throughput increases as grit
size decreases, reaching 90% at 790 nm with the finest polishing levels; (3)
total throughput is higher at redder wavelengths for coarser polishing grit,
indicating surface-scattering as the primary source of loss. We also quantify
the angular dependence of FRD as a function of polishing level. Our results
indicate that a commonly adopted micro-bending model for FRD is a poor
descriptor of the observed phenomenon.Comment: 10 pages, 7 figures, presented at SPIE Astronomical Telescopes and
Instrumentation, July 201
Photochemical Approaches to Complex Chemotypes: Applications in Natural Product Synthesis.
The use of photochemical transformations is a powerful strategy that allows for the formation of a high degree of molecular complexity from relatively simple building blocks in a single step. A central feature of all light-promoted transformations is the involvement of electronically excited states, generated upon absorption of photons. This produces transient reactive intermediates and significantly alters the reactivity of a chemical compound. The input of energy provided by light thus offers a means to produce strained and unique target compounds that cannot be assembled using thermal protocols. This review aims at highlighting photochemical transformations as a tool for rapidly accessing structurally and stereochemically diverse scaffolds. Synthetic designs based on photochemical transformations have the potential to afford complex polycyclic carbon skeletons with impressive efficiency, which are of high value in total synthesis.R01 GM073855 - NIGMS NIH HHS; R01 GM096129 - NIGMS NIH HHS; R35 GM118173 - NIGMS NIH HH
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Angiolymphoid hyperplasia with eosinophilia treated with Mohs micrographic surgery
A 60-year-old healthy man presented with several enlarging, tender, spontaneously bleeding, and episodically pruritic nodules on his ear. Five agminated pink-red papulonodules of the superior postauricular sulcus were noted on examination. Pathological examination revealed a lobular dermal vascular proliferation with plump endothelial cells protruding into the lumen in a hobnail pattern, along with a dense perivascular inflammatory infiltrate composed of plasma cells, lymphocytes, and numerous eosinophils. The diagnosis of angiolymphoid hyperplasia with eosinophilia was confirmed. After discussing treatment modalities, the patient opted for Mohs micrographic surgery (MMS). Three stages of MMS were able to remove all large vessel involvement and clear the peripheral margins, but the tumor had a complex branching pattern of growth in the deep bed of the wound with numerous tiny foci remaining. Owing to risk of disfigurement, no further excision was undertaken. The area was reconstructed with a temporalis fascia flap and a full-thickness skin graft. Despite remaining microscopic disease, the patient remained without recurrence or symptoms at one year of follow up
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