373 research outputs found
The Man Who Started the Civil War: James Chesnut, Honor, and Emotion in the American South
Anna Koivusalo examines arch-secessionist James Chesnutâs emotions in The Man Who Started the Civil War: James Chesnut, Honor, and Emotion in the American South. Reviewer R. Boyd Murphree writes that Koivusalo expands our understanding of honor, which she demonstrates was an emotion, ânot just a code of conduct.â The Man Who Started the Civil War âis academic in the best sense of the word: analytic, revelatory, and innovative,â Murphree writes
Elephant-to-Human Transmission of Tuberculosis, 2009
In 2009, the Tennessee Department of Health received reports of 5 tuberculin skin test (TST) conversions among employees of an elephant refuge and isolation of Mycobacterium tuberculosis from a resident elephant. To determine the extent of the outbreak and identify risk factors for TST conversion, we conducted a cohort study and onsite assessment. Risk for conversion was increased for elephant caregivers and administrative employees working in the barn housing the M. tuberculosisâinfected elephant or in offices connected to the barn (risk ratio 20.3, 95% confidence interval 2.8â146.7). Indirect exposure to aerosolized M. tuberculosis and delayed or inadequate infection control practices likely contributed to transmission. The following factors are needed to reduce risk for M. tuberculosis transmission in the captive elephant industry: increased knowledge about M. tuberculosis infection in elephants, improved infection control practices, and specific occupational health programs
Observation of ultracold atomic bubbles in orbital microgravity
Substantial leaps in the understanding of quantum systems have been driven by exploring geometry, topology, dimensionality and interactions in ultracold atomic ensembles1â6. A system where atoms evolve while confined on an ellipsoidal surface represents a heretofore unexplored geometry and topology. Realizing an ultracold bubbleâpotentially BoseâEinstein condensedârelates to areas of interest including quantized-vortex flow constrained to a closed surface topology, collective modes and self-interference via bubble expansion7â17. Large ultracold bubbles, created by inflating smaller condensates, directly tie into Hubble-analogue expansion physics18â20. Here we report observations from the NASA Cold Atom Lab21 facility onboard the International Space Station of bubbles of ultracold atoms created using a radiofrequency-dressing protocol. We observe bubble configurations of varying size and initial temperature, and explore bubble thermodynamics, demonstrating substantial cooling associated with inflation. We achieve partial coverings of bubble traps greater than one millimetre in size with ultracold films of inferred few-micrometre thickness, and we observe the dynamics of shell structures projected into free-evolving harmonic confinement. The observations are among the first measurements made with ultracold atoms in space, using perpetual freefall to explore quantum systems that are prohibitively difficult to create on Earth. This work heralds future studies (in orbital microgravity) of the BoseâEinstein condensed bubble, the character of its excitations and the role of topology in its evolution
Using Molecules to Measure Nuclear Spin-Dependent Parity Violation
Nuclear spin-dependent parity violation arises from weak interactions between
electrons and nucleons, and from nuclear anapole moments. We outline a method
to measure such effects, using a Stark-interference technique to determine the
mixing between opposite-parity rotational/hyperfine levels of ground-state
molecules. The technique is applicable to nuclei over a wide range of atomic
number, in diatomic species that are theoretically tractable for
interpretation. This should provide data on anapole moments of many nuclei, and
on previously unmeasured neutral weak couplings
Retinoblastoma
Retinoblastoma is a rare eye tumor of childhood that arises in the retina. It is the most common intraocular malignancy of infancy and childhood; with an incidence of 1/15,000â20,000 live births. The two most frequent symptoms revealing retinoblastoma are leukocoria and strabismus. Iris rubeosis, hypopyon, hyphema, buphthalmia, orbital cellulites and exophthalmia may also be observed. Sixty per cent of retinoblastomas are unilateral and most of these forms are not hereditary (median age at diagnosis two years). Retinoblastoma is bilateral in 40% of cases (median age at diagnosis one year). All bilateral and multifocal unilateral forms are hereditary. Hereditary retinoblastoma constitutes a cancer predisposition syndrome: a subject constitutionally carrying an RB1 gene mutation has a greater than 90% risk of developing retinoblastoma but is also at increased risk of developing other types of cancers. Diagnosis is made by fundoscopy. Ultrasound, magnetic resonance imaging (MRI) and computed tomography (CT) scans may contribute to diagnosis. Management of patients with retinoblastoma must take into account the various aspects of the disease: the visual risk, the possibly hereditary nature of the disease, the life-threatening risk. Enucleation is still often necessary in unilateral disease; the decision for adjuvant treatment is taken according to the histological risk factors. Conservative treatment for at least one eye is possible in most of the bilateral cases. It includes laser alone or combined with chemotherapy, cryotherapy and brachytherapy. The indication for external beam radiotherapy should be restricted to large ocular tumors and diffuse vitreous seeding because of the risk of late effects, including secondary sarcoma. Vital prognosis, related to retinoblastoma alone, is now excellent in patients with unilateral or bilateral forms of retinoblastoma. Long term follow-up and early counseling regarding the risk of second primary tumors and transmission should be offered to retinoblastoma patients
Characterization of human and rodent native and recombinant adenosine A2B receptors by radioligand binding studies
Adenosine A2B receptors of native human and rodent cell lines were investigated using [3H]PSB-298 [(8-{4-[2-(2-hydroxyethylamino)-2-oxoethoxy]phenyl}-1-propylxanthine] in radioligand binding studies. [3H]PSB-298 showed saturable and reversible binding. It exhibited a KD value of 60 Âą 1 nM and limited capacity (Bmax = 3.511 fmol per milligram protein) at recombinant human adenosine A2B receptors expressed in human embryonic kidney cells (HEK-293). The addition of sodium chloride (100 mM) led to a threefold increase in the number of binding sites recognized by the radioligand. The curve of the agonist 5â˛-N-ethylcarboxamidoadenosine (NECA) was shifted to the right in the presence of NaCl, while the curve of the antagonist PSB-298 was shifted to the left, indicating that PSB-298 may be an inverse agonist at A2B receptors. Adenosine A2B receptors were shown to be the major adenosine A2 receptor subtype on the mouse neuroblastoma x rat glioma hybrid cell line NG108-15 cells. Binding studies at rat INS-1 cells (insulin secreting cell line) demonstrated that [3H]PSB-298 is a selective radioligand for adenosine A2B binding sites in this cell line
First results from the JWST Early Release Science Program Q3D: Benchmark Comparison of Optical and Mid-IR Tracers of a Dusty, Ionized Red Quasar Wind at z=0.435
The [OIII] 5007 A emission line is the most common tracer of warm, ionized
outflows in active galactic nuclei across cosmic time. JWST newly allows us to
use mid-infrared spectral features at both high spatial and spectral resolution
to probe these same winds. Here we present a comparison of ground-based,
seeing-limited [OIII] and space-based, diffraction-limited [SIV] 10.51 micron
maps of the powerful, kpc-scale outflow in the Type 1 red quasar SDSS
J110648.32+480712.3. The JWST data are from the Mid-InfraRed Instrument (MIRI).
There is a close match in resolution between the datasets (0."4--0."6), in
ionization potential of the O+2 and S+3 ions (35 eV), and in line sensitivity
(1e-17 to 2e-17 erg/s/cm2/arcsec2). The [OIII] and [SIV] line shapes match in
velocity and linewidth over much of the 20 kpc outflowing nebula, and [SIV] is
the brightest line in the rest-frame 3.5--19.5 micron range, demonstrating its
usefulness as a mid-IR probe of quasar outflows. [OIII] is nevertheless
intriniscally brighter and provides better contrast with the point-source
continuum, which is strong in the mid-IR. There is a strong anticorrelation of
[OIII]/[SIV] with average velocity, which is consistent with a scenario of
differential obscuration between the approaching (blueshifted) and receding
(redshifted) sides of the flow. The dust in the wind may also obscure the
central quasar, consistent with models that attribute red quasar extinction to
dusty winds.Comment: Submitted to ApJ
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