6,199 research outputs found
Direct perturbation theory on the shift of Electron Spin Resonance
We formulate a direct and systematic perturbation theory on the shift of the
main paramagnetic peak in Electron Spin Resonance, and derive a general
expression up to second order. It is applied to one-dimensional XXZ and
transverse Ising models in the high field limit, to obtain explicit results
including the polarization dependence for arbitrary temperature.Comment: 5 pages (no figures) in REVTE
Optical monitoring of gamma-ray source fields
The three gamma-ray burst source fields GBS1028+46, GBS1205+24, and GBS2252-03 have been monitored for transient optical emission for a combined total of 52 hours. No optical events were seen. The limiting magnitude for the search was M sub V = 15.8 longer and M sub V = 17.0 for 6.0 s or longer
Preoperative systemic inflammation predicts postoperative infectious complications in patients undergoing curative resection for colorectal cancer
The presence of systemic inflammation before surgery, as evidenced by the glasgow prognostic score (mGPS), predicts poor long-term survival in colorectal cancer. The aim was to examine the relationship between the preoperative mGPS and the development of postoperative complications in patients undergoing potentially curative resection for colorectal cancer. Patients (n=455) who underwent potentially curative resections between 2003 and 2007 were assessed consecutively, and details were recorded in a database. The majority of patients presented for elective surgery (85%) were over the age of 65 years (70%), were male (58%), were deprived (53%), and had TNM stage I/II disease (61%), had preoperative haemoglobin (56%), white cell count (87%) and mGPS 0 (58%) in the normal range. After surgery, 86 (19%) patients developed a postoperative complication; 70 (81%) of which were infectious complications. On multivariate analysis, peritoneal soiling (P<0.01), elevated preoperative white cell count (P<0.05) and mGPS (P<0.01) were independently associated with increased risk of developing a postoperative infection. In elective patients, only the mGPS (OR=1.75, 95% CI=1.17-2.63, P=0.007) was significantly associated with increased risk of developing a postoperative infection. Preoperative elevated mGPS predicts increased postoperative infectious complications in patients undergoing potentially curative resection for colorectal cancer
Investigating the amplitude and rotation of the phase spiral in the Milky Way outer disc
Context: With the data releases from the astrometric space mission Gaia, the
exploration of the structure of the Milky Way has developed in unprecedented
detail and unveiled many previously unknown structures in the Galactic disc and
halo. One such feature is the phase spiral where the stars in the Galactic disc
form a spiral density pattern in the plane. Aims: We aim to
characterize the shape, rotation, amplitude, and metallicity of the phase
spiral in the outer disc of the Milky Way. This will allow us to better
understand which physical processes caused the phase spiral and can give
further clues to the Milky Way's past and the events that contributed to its
current state. Methods: We use Gaia data release 3 (DR3) to get full position
and velocity data on approximately 31.5 million stars, and metallicity for a
subset of them. We then compute the angular momenta of the stars and develop a
model to characterise the phase spiral in terms of amplitude and rotation at
different locations in the disc. Results: We find that the rotation angle of
the phase spiral changes with Galactic azimuth and Galactocentric radius,
making the phase spiral appear to rotate about per degree in Galactic
azimuth. Furthermore, we find that the phase spiral in the kpc km
s range of angular momentum is particularly strong compared to the phase
spiral that can be observed in the solar neighbourhood. The metallicity of the
phase spiral appears to match that of the Milky Way disc field stars.
Conclusions: We created a new model capable of fitting several key parameters
of the phase spiral. We have been able to determine the rotation rate of the
phase spiral and found a peak in the phase spiral amplitude which manifests as
a very clear phase spiral when using only stars with similar angular momentum.Comment: Submitted to A&A. Abridge
High-Resolution Photoemission Study of MgB2
We have performed high-resolution photoemission spectroscopy on MgB2 and
observed opening of a superconducting gap with a narrow coherent peak. We found
that the superconducting gap is s-like with the gap value of 4.5 meV at 15 K.
The temperature dependence (15 - 40 K) of gap value follows well the BCS form,
suggesting that 2Delta/kBTc at T=0 is about 3. No pseudogap behavior is
observed in the normal state. The present results strongly suggest that MgB2 is
categorized into a phonon-mediated BCS superconductor in the weak-coupling
regime.Comment: 3 pages, 3 figures, accepted in Physical Review Letter
Cancer and systemic inflammation: treat the tumour and treat the host
Determinants of cancer progression and survival are multifactorial and host responses are increasingly appreciated to have a major role. Indeed, the development and maintenance of a systemic inflammatory response has been consistently observed to confer poorer outcome, in both early and advanced stage disease. For patients, cancer-associated symptoms are of particular importance resulting in a marked impact on day-to-day quality of life and are also associated with poorer outcome. These symptoms are now recognised to cluster with one another with anorexia, weight loss and physical function forming a recognised cluster whereas fatigue, pain and depression forming another. Importantly, it has become apparent that these symptom clusters are associated with presence of a systemic inflammatory response in the patient with cancer. Given the understanding of the above, there is now a need to intervene to moderate systemic inflammatory responses, where present. In this context the rationale for therapeutic intervention using nonselective anti-inflammatory agents is clear and compelling and likely to become a part of routine clinical practice in the near future. The published literature on therapeutic intervention using anti-inflammatory agents for cancer-associated symptoms was reviewed. There are important parallels with the development of useful treatments for the systemic inflammatory response in patients with rheumatological disease and cardiovascular disease
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