226 research outputs found
Recent thermodynamic results from lattice QCD analyzed within a quasi-particle model
The thermodynamic behavior of QCD matter at high temperature is currently
studied by lattice QCD theory. The main features are the fast rise of the
energy density around the critical temperature and the large
trace anomaly of the energy momentum tensor
which hints at a strongly interacting system. Such features can be accounted
for by employing a massive quasi-particle model with a temperature-dependent
bag constant. Recent lattice QCD calculations with physical quark masses by the
Wuppertal-Budapest group have shown a slower increase of and a
smaller peak with respect to previous results from the
hotQCD collaboration. We investigate the implications of such differences from
the point of view of a quasi-particle model, also discussing light and strange
quark number susceptibilities. Furthermore, we predict the impact of these
discrepancies on the temperature-dependence of the transport properties of
matter, like the shear and bulk viscosities.Comment: 18 pages, 9 figures; version accepted in Phys. Rev.D; calculation
with relaxation time \tau \sim g^4 ln g has been adde
Supporting Behavior Change After AECOPD – Development of a Hospital-Initiated Intervention Using the Behavior Change Wheel
After hospitalization due to acute COPD exacerbations, patient-manageable behaviors influence rehospitalization frequency. This study’s aim was to develop a hospital-ward-initiated Behaviour-Change-Wheel (BCW)-based intervention targeting patients’ key health behaviors, with the aim to increase quality of life and reduce rehospitalization frequency. Intervention development was performed by University Hospital Zurich working groups and followed the three BCW stages for each of the three key literature-identified problems: insufficient exacerbation management, lack of physical activity and ongoing smoking. In stage one, by analyzing published evidence – including but not limited to patients’ perspective – and health professionals’ perspectives regarding these problems, we identified six target behaviors. In stage two, we identified six corresponding intervention functions. As our policy category, we chose developing guidelines and service provision. For stage three, we defined eighteen basic intervention packages using 46 Behaviour Change Techniques in our basic intervention. The delivery modes will be face-to-face and telephone contact. In the inpatient setting, this behavioral intervention will be delivered by a multi-professional team. For at least 3 months following discharge, an advanced nursing practice team will continue and coordinate the necessary care package via telephone. The intervention is embedded in a broader self-management intervention complemented by integrated care components. The BCW is a promising foundation upon which to develop our COPD intervention. In future, the interaction between the therapeutic care team-patient relationships and the delivery of the behavioral intervention will also be evaluated.
Keywords: AECOPD, complex intervention, behavior, behavior change, intervention developmen
Variable stars in the Fornax dSph Galaxy. II. Pulsating stars below the horizontal branch
We have carried out an intensive survey of the northern region of the Fornax
dwarf spheroidal galaxy with the aim of detecting the galaxy's short--period
pulsating stars (P<0.25 days). Observations collected over three consecutive
nights with the Wide Field Imager of the 2.2m MPI telescope at ESO allowed us
to detect 85 high-amplitude (0.20-1.00 mag in B-light) variable stars with
periods in the range from 0.046 to 0.126 days, similar to SX Phoenicis stars in
Galactic metal-poor stellar populations. The plots of the observed periods vs.
the B and V magnitudes show a dispersion largely exceeding the observational
errors. To disentangle the matter, we separated the first-overtone from the
fundamental-mode pulsators and tentatively identified a group of subluminous
variables, about 0.35 mag fainter than the others. Their nature as either
metal-poor intermediate-age stars or stars formed by the merging of close
binary systems is discussed. The rich sample of the Fornax variables also led
us to reconstruct the Period-Luminosity relation for short-period pulsating
stars. An excellent linear fit, M(V)=-1.83(+/-0.08)-3.65(+/-0.07) log P(fund),
was obtained using 153 Delta Scuti and SX Phoenicis stars in a number of
different stellar systems.Comment: 11 pages plus 1 on-line figure and 1 on-line table; accepted for
publication in ApJ. Part of this work has been the subject of the Laurea
thesis of LDA. His supervisor and our colleague, Prof. Laura E. Pasinetti,
suddendly passed away on September 13, 2006. Several astronomers have been
trained under her tutelage and we gratefully honor her memor
Pharmacophore Hybridization To Discover Novel Topoisomerase II Poisons with Promising Antiproliferative Activity
We used a pharmacophore hybridization strategy to combine key structural elements of merbarone and etoposide and generated new type II topoisomerase (topoII) poisons. This first set of hybrid topoII poisons shows promising antiproliferative activity on human cancer cells, endorsing their further exploration for anticancer drug discovery
Widespread, long-term admixture between grey wolves and domestic dogs across Eurasia and its implications for the conservation status of hybrids
Hybridisation between a domesticated species and its wild ancestor is an important conservation problem, especially if it results in the introgression of domestic gene variants into wild species. Nevertheless, the legal status of hybrids remains unregulated, partially because of the limited understanding of the hybridisation process and its consequences. The occurrence of hybridisation between grey wolves and domestic dogs is well-documented from different parts of the wolf geographic range, but little is known about the frequency of hybridisation events, their causes and the genetic impact on wolf populations. We analysed 61K SNPs spanning the canid genome in wolves from across Eurasia and North America and compared that data to similar data from dogs to identify signatures of admixture. The haplotype block analysis, which included 38 autosomes and the X chromosome, indicated the presence of individuals of mixed wolf-dog ancestry in most Eurasian wolf populations, but less admixture was present in North American populations. We found evidence for male-biased introgression of dog alleles into wolf populations, but also identified a first-generation hybrid resulting from mating between a female dog and a male wolf. We found small blocks of dog ancestry in the genomes of 62% Eurasian wolves studied and melanistic individuals with no signs of recent admixed ancestry, but with a dog-derived allele at a locus linked to melanism. Consequently, these results suggest that hybridisation has been occurring in different parts of Eurasia on multiple timescales and is not solely a recent phenomenon. Nevertheless, wolf populations have maintained genetic differentiation from dogs, suggesting that hybridisation at a low frequency does not diminish distinctiveness of the wolf gene pool. However, increased hybridisation frequency may be detrimental for wolf populations, stressing the need for genetic monitoring to assess the frequency and distribution of individuals resulting from recent admixture
Incidence and risk factors for gallstones in patients with inflammatory bowel disease: a large case-control study
The risk for gallstones (GD) in inflammatory bowel diseases and the factors responsible for this complication have not been well established. We studied the incidence of GD in a cohort of Crohn's disease (CD) and ulcerative colitis (UC) patients and investigated the related risk factors. A case-controlled study was carried out. The study population included 634 inflammatory bowel disease (IBD) patients (429 CD, 205 UC) and 634 age-matched, sex-matched, and body mass index (BMI)-matched controls free of GD at enrollment, who were followed for a mean of 7.2 years (range, 5-11 years).The incidence of GD was calculated by dividing the number of events per person-years of follow-up. Multivariate analysis was used to discriminate among the impact of different variables on the risk of developing GD. The incidence rates of GD were 14.35/1,000 persons/year in CD as compared with 7.75 in matched controls (P=0.012) and 7.48/1000 persons/year in UC patients as compared with 6.06 in matched-controls (P=0.38). Ileo-colonic CD location (OR, 2.14), disease duration>15 years (OR, 4.26), >3 clinical recurrences (OR, 8.07), ileal resection>30 cm (OR, 7.03), >3 hospitalizations (OR, 20.7), multiple TPN treatments (OR, 8.07), and long hospital stay (OR, 24.8) were significantly related to GD in CD patients. CONCLUSION: Only CD patients have a significantly higher risk of developing GD than well-matched hospital controls. Site of disease at diagnosis, lifetime surgery, extent of ileal resections, number of clinical recurrences, TPN, and the frequency and duration of hospitalizations are independently associated with GD
Variable stars in the Fornax dSph Galaxy. I. The Globular Cluster Fornax 4
Variable stars have been identified for the first time in Fornax 4, the
globular cluster located near the center of the Fornax dwarf spheroidal galaxy.
By applying the image subtraction technique to B,V time series photometry
obtained with the MagIC camera of the 6.5-m Magellan/Clay telescope and with
the wide field imager of the 4-m Blanco/CTIO telescope, we detected 27 RR Lyrae
stars (22 fundamental mode, 3 first overtone, and 2 double-mode pulsators) in a
2.4'x2.4' area centered on Fornax 4. The average and minimum periods of the
ab-type RR Lyrae stars, = 0.594 d and P(ab,min)=0.5191 d, respectively, as
well as the revised position of the cluster in the horizontal branch
type--metallicity plane, all consistently point to an Oosterhoff-intermediate
status for the cluster, unlike what is seen for the vast majority of Galactic
globular clusters, but in agreement with previous indications for the other
globular clusters in Fornax.
The average apparent magnitude of the RR Lyrae stars located within 30 arcsec
from the cluster center is =21.43 +/- 0.03 mag (sigma=0.10 mag, average
on 12 stars), leading to a true distance modulus of (m-M)o=20.64 +/- 0.09 mag
or (m-M)o=20.53 +/- 0.09 mag, depending on whether a low ([Fe/H]=-2.0) or a
moderately high ([Fe/H]=-1.5) metallicity is adopted.Comment: Apj, in pres
Neuropathologic features in the hippocampus and cerebellum of three older men with fragile X syndrome
<p>Abstract</p> <p>Background</p> <p>Fragile X syndrome (FXS) is the most common inherited form of intellectual disability, and is the most common single-gene disorder known to be associated with autism. Despite recent advances in functional neuroimaging and our understanding of the molecular pathogenesis, only limited neuropathologic information on FXS is available.</p> <p>Methods</p> <p>Neuropathologic examinations were performed on post-mortem brain tissue from three older men (aged 57, 64 and 78 years) who had received a clinical or genetic diagnosis of FXS. In each case, physical and cognitive features were typical of FXS, and one man was also diagnosed with autism. Guided by reports of clinical and neuroimaging abnormalities of the limbic system and cerebellum of individuals with FXS, the current analysis focused on neuropathologic features present in the hippocampus and the cerebellar vermis.</p> <p>Results</p> <p>Histologic and immunologic staining revealed abnormalities in both the hippocampus and cerebellar vermis. Focal thickening of hippocampal CA1 and irregularities in the appearance of the dentate gyrus were identified. All lobules of the cerebellar vermis and the lateral cortex of the posterior lobe of the cerebellum had decreased numbers of Purkinje cells, which were occasionally misplaced, and often lacked proper orientation. There were mild, albeit excessive, undulations of the internal granular cell layer, with patchy foliar white matter axonal and astrocytic abnormalities. Quantitative analysis documented panfoliar atrophy of both the anterior and posterior lobes of the vermis, with preferential atrophy of the posterior lobule (VI to VII) compared with age-matched normal controls.</p> <p>Conclusions</p> <p>Significant morphologic changes in the hippocampus and cerebellum in three adult men with FXS were identified. This pattern of pathologic features supports the idea that primary defects in neuronal migration, neurogenesis and aging may underlie the neuropathology reported in FXS.</p
Targeted Analysis of Serum Proteins Encoded at Known Inflammatory Bowel Disease Risk Loci
Few studies have investigated the blood proteome of inflammatory bowel disease (IBD). We characterized the serum abundance of proteins encoded at 163 known IBD risk loci and tested these proteins for their biomarker discovery potential. Based on the Human Protein Atlas (HPA) antibody availability, 218 proteins from genes mapping at 163 IBD risk loci were selected. Targeted serum protein profiles from 49 Crohns disease (CD) patients, 51 ulcerative colitis (UC) patients, and 50 sex- and age-matched healthy individuals were obtained using multiplexed antibody suspension bead array assays. Differences in relative serum abundance levels between disease groups and controls were examined. Replication was attempted for CD-UC comparisons (including disease subtypes) by including 64 additional patients (33 CD and 31 UC). Antibodies targeting a potentially novel risk protein were validated by paired antibodies, Western blot, immuno-capture mass spectrometry, and epitope mapping. By univariate analysis, 13 proteins mostly related to neutrophil, T-cell, and B-cell activation and function were differentially expressed in IBD patients vs healthy controls, 3 in CD patients vs healthy controls and 2 in UC patients vs healthy controls (q <0.01). Multivariate analyses further differentiated disease groups from healthy controls and CD subtypes from UC (P <0.05). Extended characterization of an antibody targeting a novel, discriminative serum marker, the laccase (multicopper oxidoreductase) domain containing 1 (LACC1) protein, provided evidence for antibody on-target specificity. Using affinity proteomics, we identified a set of IBD-associated serum proteins encoded at IBD risk loci. These candidate proteins hold the potential to be exploited as diagnostic biomarkers of IBD.Peer reviewe
On the newly discovered Canes Venatici II dSph galaxy
We report on the detection of variable stars in the Canes Venatici II (CVn
II) dwarf spheroidal galaxy, a new satellite of the Milky Way recently
discovered by the Sloan Digital Sky Survey. We also present a V, B-V
color-magnitude diagram that reaches V = 25.5 mag, showing the galaxy's main
sequence turn off at V = 24.5 mag and revealing several candidate blue
straggler stars. Two RR Lyrae stars have been identified within the half-light
radius of CVn II,a fundamental-mode variable (RRab) with period P_ab = 0.743
days, and a first-overtone (RRc) RR Lyrae star with P_c = 0.358 days. The
rather long periods of these variables along with their position on the
period-amplitude diagram support an Oosterhoff type II classification for CVn
II. The average apparent magnitude of the RR Lyrae stars, = 21.48 +/- 0.02
mag, is used to obtain a precision distance modulus of mu_0 = 21.02 +/- 0.06
mag and a corresponding distance of 160(+4,-5} kpc, for an adopted reddening
E(B-V) = 0.015 mag.Comment: Submitted to ApJ Letter
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