205 research outputs found
Between data providers and concerned citizens: Exploring participation in precision public health in Switzerland.
This empirical article explores the dynamics of exchange and reciprocity between cohorters, that is, study organizers, and cohortees, that is, study participants. Drawing on literature on bioeconomy and valuation, we analyze cohortees' expectations in return for the "clinical labor" they perform in the pilot phase of a Swiss precision public health study. Based on an ethnography of this cohort and data from seven focus groups with cohortees (n = 37), we identified four positions: (1) the good citizen participant, (2) the critical participant, (3) the concerned participant, and (4) the self-oriented participant. These reveal that cohortees' participation, still framed in altruistic terms, nevertheless engages expectations about reciprocal obligations of the state and science in terms of public health, confirming the deep entanglement of gift-based, financial, and moral economies of participation. The different values emerging from these expectations-robust scientific evidence about environmental exposure and a socially oriented public health-provide rich indications about stake making which might matter for the future of precision public health
Does cardiac surgery in newborn infants compromise blood cell reactivity to endotoxin?
INTRODUCTION: Neonatal cardiac surgery is associated with a systemic inflammatory reaction that might compromise the reactivity of blood cells against an inflammatory stimulus. Our prospective study was aimed at testing this hypothesis. METHODS: We investigated 17 newborn infants with transposition of the great arteries undergoing arterial switch operation. Ex vivo production of the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α), of the regulator of the acute-phase response IL-6, and of the natural anti-inflammatory cytokine IL-10 were measured by enzyme-linked immunosorbent assay in the cell culture supernatant after whole blood stimulation by the endotoxin lipopolysaccharide before, 5 and 10 days after the operation. Results were analyzed with respect to postoperative morbidity. RESULTS: The ex vivo production of TNF-α and IL-6 was significantly decreased (P < 0.001 and P < 0.002, respectively), whereas ex vivo production of IL-10 tended to be lower 5 days after the operation in comparison with preoperative values (P < 0.1). Ex vivo production of all cytokines reached preoperative values 10 days after cardiac surgery. Preoperative ex vivo production of IL-6 was inversely correlated with the postoperative oxygenation index 4 hours and 24 hours after the operation (P < 0.02). In contrast, postoperative ex vivo production of cytokines did not correlate with postoperative morbidity. CONCLUSION: Our results show that cardiac surgery in newborn infants is associated with a transient but significant decrease in the ex vivo production of the pro-inflammatory cytokines TNF-α and IL-6 together with a less pronounced decrease in IL-10 production. This might indicate a transient postoperative anti-inflammatory shift of the cytokine balance in this age group. Our results suggest that higher preoperative ex vivo production of IL-6 is associated with a higher risk for postoperative pulmonary dysfunction
IGR J08408--4503: a new recurrent Supergiant Fast X-ray Transient
The supergiant fast X-ray transient IGR J08408-4503 was discovered by
INTEGRAL on May 15, 2006, during a bright flare. The source shows sporadic
recurrent short bright flares, reaching a peak luminosity of 10^36 erg s^-1
within less than one hour. The companion star is HD 74194, an Ob5Ib(f)
supergiant star located at 3 kpc in the Vela region. We report the light curves
and broad-band spectra (0.1-200 keV) of all the three flares of IGR J08408-4503
detected up to now based on INTEGRAL and Swift data. The flare spectra are well
described by a power-law model with a high energy cut-off at ~15 keV. The
absorption column density during the flares was found to be ~10^21 cm^-2,
indicating a very low matter density around the compact object. Using the
supergiant donor star parameters, the wind accretion conditions imply an
orbital period of the order of one year, a spin period of the order of hours
and a magnetic field of the order of 10^13 G.Comment: 5 pages, 2 figures, accepted for publication in Astrophysical Journal
Letter
Integral results on GRB030320: a long gamma-ray burst detected at the edge of the field of view
GRB030320 is the 5th Gamma-ray burst (GRB) detected by INTEGRAL in the field
of view (FoV). It is so far the GRB with the largest off-axis angle with
respect to the INTEGRAL pointing direction, near to the edge of the FoV of both
main instruments, IBIS and SPI. Nevertheless, it was possible to determine its
position and to extract spectra and fluxes. The GRB nature of the event was
confirmed by an IPN triangulation. It is a ~ 60 s long GRB with two prominent
peaks separated by ~ 35 s. The spectral shape of the GRB is best represented by
a single power law with a photon index Gamma ~ 1.7. The peak flux in the 20 -
200 keV band is determined to ~ 5.7 photons cm-2 s-1 and the GRB fluence to 1.1
x 10-5 erg cm-2. Analysing the spectral evolution of the GRB, a
``hard-to-soft'' behaviour emerges. A search for an optical counterpart has
been carried out, but none was found.Comment: 5 pages, 3 figures. Accepted for publication in A&AL (INTEGRAL issue
The INTEGRAL view of the Soft Gamma-ray Repeater SGR 1806-20
We present the results obtained by INTEGRAL on the Soft-Gamma Ray Repeater
SGR 1806-20. In particular we report on the temporal and spectral properties of
the bursts detected during a moderately active period of the source in
September and October 2003 and on the search for quiescent emission.Comment: To appear in the proceedings (ESA-SP) of the 5th INTEGRAL Workshop,
"The INTEGRAL UNIVERSE", Munich, 16-20 February 200
A detailed spectral study of GRB 041219A and its host galaxy
GRB 041219A is one of the longest and brightest gamma-ray bursts (GRBs) ever
observed. It was discovered by the INTEGRAL satellite, and thanks to a
precursor happening about 300 s before the bulk of the burst, ground based
telescopes were able to catch the rarely-observed prompt emission in the
optical and in the near infrared bands. Here we present the detailed analysis
of its prompt gamma-ray emission, as observed with IBIS on board INTEGRAL, and
of the available X-ray afterglow data collected by XRT on board Swift. We then
present the late-time multi-band near infrared imaging data, collected at the
TNG, and the CFHT, that allowed us to identify the host galaxy of the GRB as an
under-luminous, irregular galaxy of about 5x10^9 M_Sun at best fit redshift of
z=0.31 -0.26 +0.54. We model the broad-band prompt optical to gamma-ray
emission of GRB 041219A within the internal shock model. We were able to
reproduce the spectra and light curve invoking the synchrotron emission of
relativistic electrons accelerated by a series of propagating shock waves
inside a relativistic outflow. On the other hand, it is less easy to
simultaneously reproduce the temporal and spectral properties of the infrared
data.Comment: 12 pages, 9 figures, accepted for publication in MNRAS, Figure 5 in
reduced qualit
Lattice dependence of saturated ferromagnetism in the Hubbard model
We investigate the instability of the saturated ferromagnetic ground state
(Nagaoka state) in the Hubbard model on various lattices in dimensions d=2 and
d=3. A variational resolvent approach is developed for the Nagaoka instability
both for U = infinity and for U < infinity which can easily be evaluated in the
thermodynamic limit on all common lattices. Our results significantly improve
former variational bounds for a possible Nagaoka regime in the ground state
phase diagram of the Hubbard model. We show that a pronounced particle-hole
asymmetry in the density of states and a diverging density of states at the
lower band edge are the most important features in order to stabilize Nagaoka
ferromagnetism, particularly in the low density limit.Comment: Revtex, 18 pages with 18 figures, 7 pages appendices, section on bcc
lattice adde
The role of polysaccharide intercellular adhesin (PIA) in Staphylococcus epidermidis adhesion to host tissues and subsequent antibiotic tolerance
The aim of this study was to determine the role of polysaccharide intercellular adhesin (PIA) in Staphylococcus epidermidis adhesion to host tissues and subsequent antibiotic tolerance. The adherence of S. epidermidis 1457 and the mutant defective in PIA production (1457-M10) to urinary epithelium and endothelium was estimated by colony counting. Minimum bactericidal concentration and mean reduction of cellular activity (XTT) following antibiotic exposure was determined for planktonic and adhered bacteria. S. epidermidis 1457 adhered to a greater extent to both cells than the mutant strain. The adhered strains had a significantly higher antimicrobial tolerance than their planktonic counterparts. The mutant strain was, in general, the most susceptible to the antibiotics assayed. In conclusion, PIA may influence S. epidermidis adherence to host tissues and their antimicrobial susceptibility. Initial adhesion may be the main step for the acquisition of resistance in S. epidermidis
The first GRB survey of the IBIS/PICsIT archive
The multi-purpose INTEGRAL mission is continuously contributing to Gamma Ray
Burst (GRB) science, thanks to the performances of its two main instruments,
IBIS and SPI, operating in the hard X-ray/soft gamma-ray domain. We investigate
the possibilities offered to the study of GRBs by PICsIT, the high-energy
detector of the IBIS instrument. We searched for transient episodes in the
PICsIT light curves archive from May 2006 to August 2009, using stringent
criteria optimized for the detection of long events. In the time interval under
examination PICsIT provides an energy coverage from 208 to 2600 keV, resolved
in eight energy channels, combined with a fine time resolution of 16 ms. PICsIT
successfully observes GRBs in the 260-2600 keV energy range with an incoming
direction spread over half the sky for the brightest events. We compiled a list
of 39 bursts, most of which are confirmed GRBs or simultaneous to triggers from
other satellites/instruments. We produced light curves with a time sampling
down to 0.25 s in three energy intervals for all events. Because an adequate
response matrix is not yet available for the PICsIT burst sample, we obtained a
calibration coefficient in three selected energy bands by comparing
instrumental counts with physical fluences inferred from observations with
different satellites. The good time resolution provided by the PICsIT data
allows a spectral variability study of our sample through the hardness ratio.Comment: 20 pages, 48 figures. Accepted for publication in A&
- …