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Making Sense of Family Deaths in Urban Senegal: Diversities, Contexts, and Comparisons
Despite calls for cross-cultural research, Minority world perspectives still dominate death and bereavement studies, emphasizing individualized emotions and neglecting contextual diversities. In research concerned with contemporary African societies, on the other hand, death and loss are generally subsumed within concerns about AIDS or poverty, with little attention paid to the emotional and personal significance of a death. Here, we draw on interactionist sociology to present major themes from a qualitative study of family deaths in urban Senegal, theoretically framed through the duality of meanings-in-context. Such themes included family and community as support and motivation; religious beliefs and practices as frameworks for solace and (regulatory) meaning; and material circumstances as these are intrinsically bound up with emotions. Although we identify the experience of (embodied, emotional) pain as a common response across Minority and Majority worlds, we also explore significant divergencies, varying according to localized contexts and broader power dynamics
Nuclear activity and star formation properties of Seyfert 2 galaxies
In order to characterize the amount of recent or ongoing stellar formation in
the circumnuclear region of active galaxies on a statistically sound basis, we
have studied the stellar component of the nuclear spectra in three different
samples of galaxies, namely Seyfert 2 galaxies (hereafter S2G), star-forming
galaxies (SFG) and passive normal galaxies (NG), i.e., no emission lines
observed, using Sloan Digital Sky Survey data (SDSS) (Adelman-McCarthy, 2008).
The stellar component of the observed spectra has been extracted using
STARLIGHT (Cid Fernandes et al., 2004), which fits an observed spectrum with a
model (template) spectrum obtained by combining a library of pre-defined simple
stellar populations spectra, with distinct ages and metallicities. The
resulting template spectra for the different samples of galaxies have been
compared to determine the features of the stellar emission component and to
evaluate the presence and intensity of the star formation in the nuclear
regions of different families of galaxies. From a first qualitative analysis it
results that the shape of the Spectral Energy Distribution (SED) of S2G and NG
is very similar, while that of SFG is characterized by a strong blue excess.
The presence of the 4000 A break in the spectra of S2G and NG together with the
lack of a strong blue continuum clearly indicate the absence of ongoing star
formation in the circumnuclear regions of S2G and obviously of NG. Anyway
traces of a recent star formation history are evident in the spectra of S2G
galaxies, which show a 4000 A break systematically shallower than in NG.Comment: Proceeding of the VII Serbian Conference on Spectral Line Shapes in
Astrophysic
Slit2 guides both precrossing and postcrossing callosal axons at the midline in vivo
Commissural axons generally cross the midline only once. In the Drosophila nerve cord and mouse spinal cord, commissural axons are guided by Slit only after they cross the midline, where Slit prevents these axons from recrossing the midline. In the developing corpus callosum, Slit2 expressed by the glial wedge guides callosal axons before they cross the midline, as they approach the corticoseptal boundary. These data highlighted a potential difference between the role of Slit2 in guiding commissural axons in the brain compared with the spinal cord. Here, we investigate whether Slit2 also guides callosal axons after they cross the midline. Because such questions cannot be addressed in conventional gene knock-out animals, we used in utero injections of antisense oligonucleotides to specifically deplete Slit2 on only one side of the brain. We used this technique together with a novel in vitro assay of hemisected brain slices to specifically analyze postcrossing callosal axons. We find that in the brain, unlike the spinal cord, Slit2 mediates both precrossing and postcrossing axonal guidance. Depletion of Slit2 on one side of the brain causes axons to defasciculate and, in some cases, to aberrantly enter the septum. Because these axons do not recross the midline, we conclude that the principle function of Slit2 at the cortical midline maybe to channel the axons along the correct path and possibly repel them away from the midline. We find no evidence that Slit2 prevents axons from recrossing the midline in the brain
First Laboratory Detection of N13CO-and Semiexperimental Equilibrium Structure of the NCO-Anion
The cyanate anion (NCO-) is a species of considerable astrophysical relevance. It is widely believed to be embedded in interstellar ices present in young stellar objects but has not yet been detected in the dense gas of the interstellar medium. Here we report highly accurate laboratory measurements of the rotational spectrum of the N13CO-isotopologue at submillimeter wavelengths along with the detection of three additional lines of the parent isotopologue up to 437.4 GHz. With this new data, the rotational spectrum of both isotopologues can be predicted to better 0.25 km s-1in equivalent radial velocity up to 1 THz, more than adequate for an astronomical search in any source. Moreover, a semiexperimental equilibrium structure of the anion is derived by combining the experimental ground-state rotational constants of the two isotopologues with theoretical vibrational corrections, obtained by using the coupled-cluster method with inclusion of single and double excitations and perturbative inclusion of triple excitations (CCSD(T)). The estimated accuracy of the two bond distances is on the order of 5 × 10-4Å: a comparison to the values obtained by geometry optimization with the CCSD(T) method and the use of a composite scheme, including additivity and basis-set extrapolation techniques, reveals that this theoretical procedure is very accurate
Optical-Model Description of Time-Reversal Violation
A time-reversal-violating spin-correlation coefficient in the total cross
section for polarized neutrons incident on a tensor rank-2 polarized target is
calculated by assuming a time-reversal-noninvariant, parity-conserving
``five-fold" interaction in the neutron-nucleus optical potential. Results are
presented for the system for neutron incident energies
covering the range 1--20 MeV. From existing experimental bounds, a strength of
keV is deduced for the real and imaginary parts of the five-fold
term, which implies an upper bound of order on the relative -odd
strength when compared to the central real optical potential.Comment: 11 pages (Revtex
UGC 7388: a galaxy with two tidal loops
We present the results of spectroscopic and morphological studies of the
galaxy UGC7388 with the 8.1-m Gemini North telescope. Judging by its observed
characteristics, UGC7388 is a giant late-type spiral galaxy seen almost
edge-on. The main body of the galaxy is surrounded by two faint (\mu(B) ~ 24
and \mu(B) ~ 25.5) extended (~20-30 kpc) loop-like structures. A large-scale
rotation of the brighter loop about the main galaxy has been detected. We
discuss the assumption that the tidal disruption of a relatively massive
companion is observed in the case of UGC7388. A detailed study and modeling of
the observed structure of this unique galaxy can give important information
about the influence of the absorption of massive companions on the galactic
disks and about the structure of the dark halo around UGC7388.Comment: 8 pages, 5 figure
Fock space resolutions of the Virasoro highest weight modules with c<=1
We extend Felder's construction of Fock space resolutions for the Virasoro
minimal models to all irreducible modules with . In particular, we
provide resolutions for the representations corresponding to the boundary and
exterior of the Kac table.Comment: 14 pages, revised versio
Real-time cine and myocardial perfusion with treadmill exercise stress cardiovascular magnetic resonance in patients referred for stress SPECT
Background: To date, stress cardiovascular magnetic resonance (CMR) has relied on pharmacologic agents, and
therefore lacked the physiologic information available only with exercise stress.
Methods: 43 patients age 25 to 81 years underwent a treadmill stress test incorporating both Tc99m SPECT and CMR.
After rest Tc99m SPECT imaging, patients underwent resting cine CMR. Patients then underwent in-room exercise
stress using a partially modified treadmill. 12-lead ECG monitoring was performed throughout. At peak stress, Tc99m
was injected and patients rapidly returned to their prior position in the magnet for post-exercise cine and perfusion
imaging. The patient table was pulled out of the magnet for recovery monitoring. The patient was sent back into the
magnet for recovery cine and resting perfusion followed by delayed post-gadolinium imaging. Post-CMR, patients
went to the adjacent SPECT lab to complete stress nuclear imaging. Each modality's images were reviewed blinded to
the other's results.
Results: Patients completed on average 9.3 ± 2.4 min of the Bruce protocol. Stress cine CMR was completed in 68 ± 14
sec following termination of exercise, and stress perfusion CMR was completed in 88 ± 8 sec. Agreement between
SPECT and CMR was moderate (κ = 0.58). Accuracy in eight patients who underwent coronary angiography was 7/8 for
CMR and 5/8 for SPECT (p = 0.625). Follow-up at 6 months indicated freedom from cardiovascular events in 29/29 CMRnegative
and 33/34 SPECT-negative patients.
Conclusions: Exercise stress CMR including wall motion and perfusion is feasible in patients with suspected ischemic
heart disease. Larger clinical trials are warranted based on the promising results of this pilot study to allow comparative
effectiveness studies of this stress imaging system vs. other stress imaging modalities
Two more disk galaxies with global gas counterrotation
We report a discovery of extended counterrotating gaseous disks in early-type
disk galaxies NGC 2551 and NGC 5631. To find them, we have undertaken complex
spectral observations including integral-field spectroscopy for the central
parts of the galaxies and long-slit deep spectroscopy to probe the external
parts. The line-of-sight velocity fields have been constructed and compared to
the photometric structure of the galaxies. As a result, we have revealed
full-size counterrotating gaseous disks, the one coplanar to the stellar disk
in NGC 2551 and the other inclined to the main stellar disk in NGC 5631. We
suggest that we observe the early stages of minor-merger events which may be
two different stages of the process of lenticular galaxy formation in rather
sparse environments.Comment: 8 pages, 8 EPS figures, accepted for publication in Ap
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