1,146 research outputs found
On Type II strings in exact superconformal non-constant RR backgrounds
An explicitly exact superconformal description is provided to some classes of
Type II string theories in non constant RR backgrounds. This is done by
applying the manifest (2,2) approach of Berkovits and Maldacena to Type II
strings and by studying the condition of exact conformal invariance of certain
supersymmetric backgrounds. We find a new set of exact type IIA strings with
non constant RR 2-form and 4-form curvatures and for type IIB with non constant
3-form curvature.Comment: 15 pages; typos and a reference adde
A demographic and ecological study of an Italian population of Polyommatus ripartii: the ESU Polyommatus exuberans
Exact solution of Kerr black hole perturbations via CFT2 and instanton counting: Greybody factor, quasinormal modes, and Love numbers
We give explicit expressions for the finite frequency greybody factor, quasinormal modes, and Love numbers of Kerr black holes by computing the exact connection coefficients of the radial and angular parts of the Teukolsky equation. This is obtained by solving the connection problem of the confluent Heun equation in terms of the explicit expression of irregular Virasoro conformal blocks as sums over partitions via the Alday, Gaiotto, and Tachikawa correspondence. In the relevant approximation limits our results are in agreement with existing literature. The method we use can be extended to solve the linearized Einstein equation in other interesting gravitational backgrounds
The stringy instanton partition function
We perform an exact computation of the gauged linear sigma model associated to a D1-D5 brane system on a resolved A 1 singularity. This is accomplished via supersymmetric localization on the blown-up two-sphere. We show that in the blow-down limit the partition function reduces to the Nekrasov partition function evaluating the equivariant volume of the instanton moduli space. For finite radius we obtain a tower of world-sheet instanton corrections, that we identify with the equivariant Gromov-Witten invariants of the ADHM moduli space. We show that these corrections can be encoded in a deformation of the Seiberg-Witten prepotential. From the mathematical viewpoint, the D1-D5 system under study displays a twofold nature: the D1-branes viewpoint captures the equivariant quantum cohomology of the ADHM instanton moduli space in the Givental formalism, and the D5-branes viewpoint is related to higher rank equivariant Donaldson-Thomas invariants
Evaluation of different methods to estimate the transfer of immunity in donkey foals fed with colostrum of good IgG quality: A preliminary study
The aims of the present study were to evaluate the correlation between IgG Serum Radial Immunodiffusion (SRID), Electrophoresis Gamma Globulins (EGG), Electrophoresis Total Protein (ETP) and the serum total protein (TP) analyzed by refractometry and by a dry chemistry analyzer (Biuret) and to estimate serum IgG concentrations using serum TP. A total of 36 samples collected at four different times (birth, 6, 12, 24 hours after birth) from nine Amiata donkey foals were evaluated with SRID, EGG, ETP, serum TP Biuret and refractometry. SRID IgG concentration increased significantly over time until T12. Serum TP analyzed with refractometry, electrophoresis and Biuret showed a statistically significant difference between T0 and T6 vs T12 and T24. A good or strong correlation was found between different tests performed. Equations to quantify serum IgG were created and can be used for estimating the donkey foals’ serum IgG in the first day of life. Serum TP refractometry showed a high correlation with SRID IgG (0.91) which may be a particularly useful and economic instrument to estimate the transfer of immunity in donkey foals during the first day of life
Development of an innovative film‑forming cleaning system for the removal of corrosion products from copper alloy artifacts
Parent field theory and unfolding in BRST first-quantized terms
For free-field theories associated with BRST first-quantized gauge systems,
we identify generalized auxiliary fields and pure gauge variables already at
the first-quantized level as the fields associated with algebraically
contractible pairs for the BRST operator. Locality of the field theory is taken
into account by separating the space--time degrees of freedom from the internal
ones. A standard extension of the first-quantized system, originally developed
to study quantization on curved manifolds, is used here for the construction of
a first-order parent field theory that has a remarkable property: by
elimination of generalized auxiliary fields, it can be reduced both to the
field theory corresponding to the original system and to its unfolded
formulation. As an application, we consider the free higher-spin gauge theories
of Fronsdal.Comment: LaTeX, amsart++, 40 pages, references added, final version to appear
in Commun. Math. Phy
Renal Measures in Healthy Italian Trotter Foals and Correlation Between Renal and Biometric Measures: Preliminary Study
The aim of this study was to evaluate ultrasonographic renal measures in healthy foals aged 1–6 weeks and to verify the correlation between biometric measures to ultrasonographic renal ones. A total of nine Italian trotter foals born in the same stud farm and underwent similar management conditions were enrolled. Inclusion criteria were normal gestation time, unassisted delivery, and normal physical examination at all evaluation times. Length and height of both kidneys were measured by ultrasound weekly from 1 to 6 weeks of life, along with the thoracic and the middle third of the metacarpal area circumferences. Data were expressed as mean and standard deviation, and distribution was evaluated. One-way analysis of variance (ANOVA) was applied to verify differences related to time. The Pearson correlation test was carried out to evaluate the linearity between time versus all the parameters measured. Student's t test was used to verify differences in ultrasound measures between right and left kidney at all recorded times. The Pearson test was applied to a mean-variance matrix to verify the correlation between each biometrical versus all renal measures. Significance level was set at P <.05. One-way ANOVA showed differences in biometric and renal measures related to time. Correlation test revealed a linear growth. Differences in ultrasound renal measures between right and left kidney were obtained. Correlation was found between biometrical parameters versus kidney measures. Renal measures and differences between left and right kidneys were in line with literature. Correlation test revealed a linear growth. Renal growth is correlated with age and biometric measure
Film forming PVA-based cleaning systems for the removal of corrosion products from historical bronzes
On manifolds admitting the consistent Lagrangian formulation for higher spin fields
We study a possibility of Lagrangian formulation for free higher spin bosonic
totally symmetric tensor field on the background manifold characterizing by the
arbitrary metric, vector and third rank tensor fields in framework of BRST
approach. Assuming existence of massless and flat limits in the Lagrangian and
using the most general form of the operators of constraints we show that the
algebra generated by these operators will be closed only for constant curvature
space with no nontrivial coupling to the third rank tensor and the strength of
the vector fields. This result finally proves that the consistent Lagrangian
formulation at the conditions under consideration is possible only in constant
curvature Riemann space.Comment: 11 pages; v2: minor typos corrected, a reference adde
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