5,431 research outputs found
Structure Functions in Deep Inelastic Lepton-Nucleon Scattering
Latest results on structure functions, as available at the Lepton-Photon
Symposium 1999, are presented. This report focusses on three experimental
areas: new structure function measurements, in particular from HERA at low x
and high Q2; results on light and heavy flavour densities; determinations of
the gluon distribution and of alpha_s. As the talk was delivered at a historic
moment and place, a few remarks were added recalling the exciting past and
looking into the promising future of deep inelastic scattering.Comment: 27 pages, latex, 15 figures, Talk at Lepton-Photon Symposium,
Stanford, August 199
Cascading Quivers from Decaying D-branes
We use an argument analogous to that of Kachru, Pearson and Verlinde to argue
that cascades in L^{a,b,c} quiver gauge theories always preserve the form of
the quiver, and that all gauge groups drop at each step by the number M of
fractional branes. In particular, we demonstrate that an NS5-brane that sweeps
out the S^3 of the base of L^{a,b,c} destroys M D3-branes.Comment: 11 pages, 1 figure; v2: references adde
On the pulsating strings in AdS_5 x T^{1,1}
We study the class of pulsating strings in AdS_5 x T^{1,1}. Using a
generalized ansatz for pulsating string configurations we find new solutions of
this class. Further we semiclassically quantize the theory and obtain the first
correction to the energy. The latter, due to AdS/CFT correspondence, is
supposed to give the anomalous dimensions of operators in the dual N=1
superconformal gauge field theory.Comment: 12 pages, improvements made, references adde
Dual giant gravitons in AdS Y (Sasaki-Einstein)
We consider BPS motion of dual giant gravitons on Ad where
represents a five-dimensional Sasaki-Einstein manifold. We find that the
phase space for the BPS dual giant gravitons is symplectically isomorphic to
the Calabi-Yau cone over , with the K\"{a}hler form identified with the
symplectic form. The quantization of the dual giants therefore coincides with
the K\"{a}hler quantization of the cone which leads to an explicit
correspondence between holomorphic wavefunctions of dual giants and
gauge-invariant operators of the boundary theory. We extend the discussion to
dual giants in where is a seven-dimensional
Sasaki-Einstein manifold; for special motions the phase space of the dual
giants is symplectically isomorphic to the eight-dimensional Calabi-Yau cone.Comment: 14 pages. (v2) typo's corrected; factors of AdS radius reinstated for
clarity; remarks about dual giant wavefunctions in T^{1,1} expanded and put
in a new subsectio
Welfare parameters in dairy cows reared in tie-stall and open-stall farming systems: pilot study
ABSTRACT. Animals can experience pain or distress as a result of widely accepted management practices. In dairy
cattle, housing system can affect animal welfare. The assessment of animal welfare requires the use of multiple indicators
in order to analyse the heterogeneity of the aspects involved. The aim of this study was to compare the welfare of
dairy cows reared in a tie-stall (TS) and open-stall (OS) system by metabolic, immunological and stress related parameters.
The study involved 80 pluriparous lactating cows belonging to eight dairy farms located in the area of Mugello
(Florence, Italy) reared in TS and OS systems. Ten blood samples were collected at morning time to measure alanine-aminotransferase
(ALT), aspartate-aminotransferase (AST), blood urea nitrogen (BUN), β-hydroxybutyrate
(BHBA), creatinine (Creat), non-esterified fatty acids (NEFA), total proteins (TP), calcium (Ca), phosphorus (P), and
potassium (K), serum lisozyme (SL), bactericidal activity (SBA), haptoglobin (Hp), oxygen free radicals (OFR), and
hair cortisol levels. At the same time a body condition score (BCS) was recorded. Statistical analysis was performed by
ANOVA. The experiment was carried out in accordance with European Commission regulations (Directive 2010/63/EC
and Directive 98/58/EC).
The results showed that the housing system affected various parameters such as ALT, BHBA, OFR, cortisol (P≤0.01)
and AST, BUN (P≤0.05). Most of these parameters showed mean values within the range of reference without revealing
any signs of suffering. An interesting outcome regarded the OFR levels, which was higher in the OS system
(68.2±34.51 U.Carr. vs 36.1±21.39 U.Carr.), probably as a consequence of the high productive effort. In conclusion, it is
possible to state that TS did not show a comparable overall situation with serious signs of welfare impairment
Protein kinase CK2 is widely expressed in follicular, Burkitt and diffuse large B-cell lymphomas and propels malignant B-cell growth.
Serine-threonine kinase CK2 is highly expressed and pivotal for survival and proliferation in multiple myeloma, chronic lymphocytic leukemia and mantle cell lymphoma. Here, we investigated the expression of \u3b1 catalytic and \u3b2 regulatory CK2 subunits by immunohistochemistry in 57 follicular (FL), 18 Burkitt (BL), 52 diffuse large B-cell (DLBCL) non-Hodgkin lymphomas (NHL) and in normal reactive follicles. In silico evaluation of available Gene Expression Profile (GEP) data sets from patients and Western blot (WB) analysis in NHL cell-lines were also performed. Moreover, the novel, clinical-grade, ATP-competitive CK2-inhibitor CX-4945 (Silmitasertib) was assayed on lymphoma cells. CK2 was detected in 98.4% of cases with a trend towards a stronger CK2\u3b1 immunostain in BL compared to FL and DLBCL. No significant differences were observed between Germinal Center B (GCB) and non-GCB DLBCL types. GEP data and WB confirmed elevated CK2 mRNA and protein levels as well as active phosphorylation of specific targets in NHL cells. CX-4945 caused a dose-dependent growth-arresting effect on GCB, non-GCB DLBCL and BL cell-lines and it efficiently shut off phosphorylation of NF-\u3baB RelA and CDC37 on CK2 target sites. Thus, CK2 is highly expressed and could represent a suitable therapeutic target in BL, FL and DLBCL NHL
New parton distributions from large-x and low-Q^2 data
We report results of a new global next-to-leading order fit of parton
distribution functions in which cuts on W and Q are relaxed, thereby including
more data at high values of x. Effects of target mass corrections (TMCs),
higher twist contributions, and nuclear corrections for deuterium data are
significant in the large-x region. The leading twist parton distributions are
found to be stable to TMC model variations as long as higher twist
contributions are also included. The behavior of the d quark as x-->1 is
particularly sensitive to the deuterium corrections, and using realistic
nuclear smearing models the d-quark distribution at large x is found to be
softer than in previous fits performed with more restrictive cuts.Comment: 31 pages, 8 figures. Minor corrections. References added. To appear
in Phys.Rev.
The curvature of as a probe of the range of validity of perturbative QCD evolutions in the small- region
Perturbative NLO and NNLO QCD evolutions of parton distributions are studied,
in particular in the (very) small- region, where they are in very good
agreement with all recent precision measurements of . These
predictions turn out to be also rather insensitive to the specific choice of
the factorization scheme ( or DIS). A characteristic feature of
perturbative QCD evolutions is a {\em{positive}} curvature of which
increases as decreases. This perturbatively stable prediction provides a
sensitive test of the range of validity of perturbative QCD.Comment: 17 pages, 6 figures, 2 tables; minor corrections, to appear in EPJ
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