3,666 research outputs found
GMOR-like relation in IR-conformal gauge theories
A generalization of the GMOR relation to the case of infrared-conformal gauge
theories is discussed. The starting point is the chiral Ward identity
connecting the isovector pseudoscalar susceptibility to the chiral condensate,
in a mass-deformed theory. A renormalization-group analysis shows that the
pseudoscalar susceptibility is not saturated by the lightest state, but a
contribution from the continuum part of the spectrum survives in the chiral
limit. The computation also shows how infrared-conformal gauge theories behave
differently, depending on whether the anomalous dimension of the chiral
condensate be smaller or larger than 1.Comment: 28 pages, 1 PDF figur
Future large-scale water-Cherenkov detector
MEMPHYS (MEgaton Mass PHYSics) is a proposed large-scale water-Cherenkov
experiment to be performed deep underground. It is dedicated to nucleon decay
searches and the detection of neutrinos from supernovae, solar, and atmospheric
neutrinos, as well as neutrinos from a future beam to measure the CP violating
phase in the leptonic sector and the mass hierarchy. This paper provides an
overview of the latest studies on the expected performance of MEMPHYS in view
of detailed estimates of its physics reach, mainly concerning neutrino beams
Study of the performance of a large scale water-Cherenkov detector (MEMPHYS)
MEMPHYS (MEgaton Mass PHYSics) is a proposed large-scale water Cherenkov
experiment to be performed deep underground. It is dedicated to nucleon decay
searches, neutrinos from supernovae, solar and atmospheric neutrinos, as well
as neutrinos from a future Super-Beam or Beta-Beam to measure the CP violating
phase in the leptonic sector and the mass hierarchy. A full simulation of the
detector has been performed to evaluate its performance for beam physics. The
results are given in terms of "Migration Matrices" of reconstructed versus true
neutrino energy, taking into account all the experimental effects.Comment: Updated after JCAP's referee's comment
Degeneracy Between the Regge Slope of Mesons and Baryons from Supersymmetry
We consider the degeneracy between the Regge slope of mesons and baryons in
QCD. We argue that within the "orientifold large-N approximation"
asymptotically massive mesons and baryons become supersymmetric partners and
hence degenerate. To this end, we generalize QCD by a SU(N) theory with a quark
in the two-index antisymmetric representation. We show that in this framework
the meson is represented by an oriented bosonic QCD-string and the baryon is
represented by an un-oriented fermionic QCD-string. At large-N, due to an
equivalence with super Yang-Mills, the tensions of the bosonic and the
fermionic strings coincide. Our description of mesons and baryons as oriented
and un-oriented bosonic and fermionic QCD-strings is in full agreement with the
spectra of open strings in the dual type 0' string theory.Comment: v2: extended version. Appendices and references adde
Hydrogeomorphic processes and torrent control works on a large alluvial fan in the eastern Italian Alps
Abstract. Alluvial fans are often present at the outlet of small drainage basins in alpine valleys; their formation is due to sediment transport associated with flash floods and debris flows. Alluvial fans are preferred sites for human settlements and are frequently crossed by transport routes. In order to reduce the risk for economic activities located on or near the fan and prevent loss of lives due to floods and debris flows, torrent control works have been extensively carried out on many alpine alluvial fans. Hazard management on alluvial fans in alpine regions is dependent upon reliable procedures to evaluate variations in the frequency and severity of hydrogeomorphic processes and the long-term performance of the torrent training works. An integrated approach to the analysis of hydrogeomorphic processes and their interactions with torrent control works has been applied to a large alluvial fan in the southern Carnic Alps (northeastern Italy). Study methods encompass field observations, interpretation of aerial photographs, analysis of historical documents, and numerical modelling of debris flows. The overall performance of control works implemented in the early decades of 20th century was satisfactory, and a reduction of hazardous events was recognised from features observed in the field and in aerial photographs, as well as from the analysis of historical records. The 2-D simulation of debris flows confirms these findings, indicating that debris flow deposition would not affect urban areas or main roads, even in the case of a high-magnitude event. Present issues in the management of the studied alluvial fan are representative of situations frequently found in the European Alps and deal with the need for maintenance of the control structures and the pressures for land use changes aimed at the economic exploitation of the fan surface
Technical note: immunomagnetic procedure for positive selection of macrophages in ovine milk.
A simple immunomagnetic procedure was developed to select macrophages from ovine milk by using a non-specific magnetic positive separation technique. Samples of ewe bulk milk were collected during early, mid, and late lactation; milk samples were centrifuged at 2,000 x g for 30 min at 4 degrees C; the fatty fraction and supernatant were removed, and each pellet was dissolved in 500 microL of pH 7.4 phosphate buffered saline + 0.02% NaN(3). Cells were targeted for selection by using mouse-IgG anti-ovine macrophages. Several trials, testing 2 different fluorochrome-conjugated antibodies [i.e., mouse anti-human CD14:R-Phycoerythrin (RPE) (MCA1568PE, Serotec) and F(ab')2 rabbit anti-mouse IgG:RPE (STAR12A, Serotec)] and 3 different labeling procedures, were performed to evaluate the purity of samples by flow cytometry. A morphological test was carried out by direct microscopic count in enriched fraction smears stained with May-Grünwald-Giemsa stain to confirm the presence of macrophages. The method described in the present technical note can be considered an innovative application to obtain a single-cell population of high purity selected from all the somatic cells in milk
Airspace effects on the yield and quality of ewe milk.
Abstract Three groups of 12 midlactating Comisana ewes were housed in separate rooms of the same building and assigned to treatments of low (LV, 4.1m 3 ), medium (MV, 5.6m 3 ), or high (HV, 7.3m 3 ) airspace/animal. The concentrations of airborne microorganisms in the experimental rooms were measured twice weekly at 0930 and 1630. Ewe milk yield was recorded daily. Individual milk samples were analyzed weekly for milk composition, coagulating properties, somatic cell concentration (SCC), and polymorphonuclear neutrophil leukocyte count (PMNLC), and fortnightly for bacteriological characteristics; samples with more than 10 6 somatic cells/ml were cultured for mastitis-related pathogens. The LV and MV treatments resulted in higher relative humidity and air concentrations of staphylococci than the HV treatment. Greater amounts of air mesophilic bacteria were also found in the LV than in the HV room. Ewes in the HV group gave greater yields of milk than those in the LV and MV groups. LV milk also had a lower casein content than HV milk. Significant interactions of treatment x time were found for milk protein and fat content as well as for clotting time and clot firmness, with LV milk having the poorest composition and deteriorated renneting ability during the last 3 wk of the trial. The HV ewes had lower SCC and PMNLC and psychrotroph counts in their milk than LV and MV ewes and smaller amounts of mesophilic bacteria and fecal coliforms than LV animals. Subclinical mastitis occurred in two ewes of the LV and one of the MV groups, while no cases were recorded in the HV group. Results suggest that airspace is a critical factor in dairy sheep housing and indicate that a volume allocation of less than 7m 3 /animal may adversely affect the performance and health of the lactating ewe
Improved Lattice Spectroscopy of Minimal Walking Technicolor
We present a numerical study of spectroscopic observables in the SU(2) gauge
theory with two adjoint fermions using improved source and sink operators. We
compare in detail our improved results with previous determinations of masses
that used point sources and sinks and we investigate possible systematic
effects in both cases. Such comparison enables us to clearly assess the impact
of a short temporal extent on the physical picture, and to investigate some
effects due to the finite spatial box. While confirming the IR-conformal
behaviour of the theory, our investigation shows that in order to make firm
quantitative predictions, a better handle on finite size effects is needed.Comment: 33 pages, 30 figures, 18 table
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