351 research outputs found
The Instanton Universal Moduli Space of N=2 Supersymmetric Yang-Mills Theory
We use the recursive structure of the compactification of the instanton
moduli space of N=2 Super Yang-Mills theory with gauge group SU(2), to
construct, by inductive limit, a universal moduli space which includes all the
multi-instanton moduli spaces. Furthermore, with the aim of understanding the
field theoretic structure of the strong coupling expansion, we perform the
Borel sum which acts on the parameter defining such a universal moduli space.Comment: 1+4 pages, LaTeX. Minor changes. To appear in Phys. Lett.
The Equivalence Principle of Quantum Mechanics: Uniqueness Theorem
Recently we showed that the postulated diffeomorphic equivalence of states
implies quantum mechanics. This approach takes the canonical variables to be
dependent by the relation p=\partial_q S_0 and exploits a basic
GL(2,C)-symmetry which underlies the canonical formalism. In particular, we
looked for the special transformations leading to the free system with
vanishing energy. Furthermore, we saw that while on the one hand the
equivalence principle cannot be consistently implemented in classical
mechanics, on the other it naturally led to the quantum analogue of the
Hamilton-Jacobi equation, thus implying the Schroedinger equation. In this
letter we show that actually the principle uniquely leads to this solution.
Furthermore, we find the map reducing any system to the free one with vanishing
energy and derive the transformations on S_0 leaving the wave function
invariant. We also express the canonical and Schroedinger equations by means of
the brackets recently introduced in the framework of N=2 SYM. These brackets
are the analogue of the Poisson brackets with the canonical variables taken as
dependent.Comment: 18 pages, LaTeX. A limit was missing in Eq.8
Evaluation of three commercial rapid kits to detect Cryptosporidium parvum in diarrheic calf stool
The aim of this study was to evaluate three commercially available rapid immunochromato-graphic tests for detection of Cryptosporidium parvum antigens in faeces of naturally infected neonatal diarrhoeic calves. FASTest (R) CRYPTO strip, FASTest (R) CRYPTO-GIARDIA Strip and TETRASTRIPS (R) were compared for their sensitivity, specificity, positive predictive value and negative predictive value using a cumulative positivity as gold standard. In addition, the agreement between each test and the gold standard was evaluated by Cohen's Kappa (k) value. The highest infection rate was observed by FASTest (R) CRYPTO GIARDIA Strip (65.15%), followed by FASTest (R) CRYPTO strip (63.64%) and TETRASTRIPS (R) (56.06%,). A very good diagnostic performance of all the three tests was observed. FASTest (R) CRYPTO strip (k= 0.935) and FASTest (R) CRYPTO-GIARDIA Strip (k= 0.968) had the highest sensitivity (100%) while TETRASTRIPS (R) (k= 0.875) had the highest specificity (100%). Eimeria spp oocysts were present in six samples but cross-reaction with this protozoan was not observed. These assays were not time-consuming and very easy to perform and to read. Based on our results, we recommend the use of FA
evaluation of three commercial rapid kits to detect cryptosporidium parvum in diarrhoeic calf stool
The aim of this study was to evaluate three commercially available rapid immunochromatographic tests for detection of Cryptosporidium parvum antigens in faeces of naturally infected neonatal diarrhoeic calves. FASTestÂź CRYPTO strip, FASTestÂź CRYPTO-GIARDIA Strip and TETRASTRIPSÂź were compared for their sensitivity, specificity, positive predictive value and negative predictive value using a cumulative positivity as gold standard. In addition, the agreement between each test and the gold standard was evaluated by Cohen's Kappa (k) value. The highest infection rate was observed by FASTestÂź CRYPTO-GIARDIA Strip (65.15%), followed by FASTestÂź CRYPTO strip (63.64%) and TETRASTRIPSÂź (56.06%,). A very good diagnostic performance of all the three tests was observed. FASTestÂź CRYPTO strip (kâ=â0.935) and FASTestÂź CRYPTO-GIARDIA Strip (kâ=â0.968) had the highest sensitivity (100%) while TETRASTRIPSÂź (kâ=â0.875) had the highest specificity (100%). Eimeria spp oocysts were present in six samples but cross-reaction with this protozoan was not observed. These assays were not time-consuming and very easy to perform and to read. Based on our results, we recommend the use of FASTestÂź CRYPTO strip, FASTestÂź CRYPTO-GIARDIA Strip or/and TETRASTRIPSÂź for detection of C. parvum antigens in faeces of neonatal diarrhoeic calves
N=2 SYM RG Scale as Modulus for WDVV Equations
We derive a new set of WDVV equations for N=2 SYM in which the
renormalization scale is identified with the distinguished modulus
which naturally arises in topological field theories.Comment: 6 pages, LaTe
Application of reverse micelle sol-gel synthesis for bulk doping and heteroatoms Surface Enrichment in Mo-Doped TiO 2 nanoparticles
TiO 2 nanoparticles containing 0.0, 1.0, 5.0, and 10.0 wt.% Mo were prepared by a reverse micelle template assisted sol-gel method allowing the dispersion of Mo atoms in the TiO 2 matrix. Their textural and surface properties were characterized by means of X-ray powder diffraction, micro-Raman spectroscopy, N 2 adsorption/desorption isotherms at -196 °C, energy dispersive X-ray analysis coupled to field emission scanning electron microscopy, X-ray photoelectron spectroscopy, diffuse reflectance UV-Vis spectroscopy, and ζ-potential measurement. The photocatalytic degradation of Rhodamine B (under visible light and low irradiance) in water was used as a test reaction as well. The ensemble of the obtained experimental results was analyzed in order to discover the actual state of Mo in the final materials, showing the occurrence of both bulk doping and Mo surface species, with progressive segregation of MoO x species occurring only at a higher Mo content
A Statistical Interpretation of Space and Classical-Quantum duality
By defining a prepotential function for the stationary Schr\"odinger equation
we derive an inversion formula for the space variable as a function of the
wave-function . The resulting equation is a Legendre transform that
relates , the prepotential , and the probability density. We
invert the Schr\"odinger equation to a third-order differential equation for
and observe that the inversion procedure implies a -
duality. This phenomenon is related to a modular symmetry due to the
superposition of the solutions of the Schr\"odinger equation. We propose that
in quantum mechanics the space coordinate can be interpreted as a macroscopic
variable of a statistical system with playing the role of a scaling
parameter. We show that the scaling property of the space coordinate with
respect to is determined by the
``beta-function''. We propose that the quantization of the inversion formula is
a natural way to quantize geometry. The formalism is extended to higher
dimensions and to the Klein-Gordon equation.Comment: 11 pages. Standard Latex. Final version to appear in Physical Review
Letters. Revised and extended version. The formalism is extended to higher
dimensions and to the Klein-Gordon equation. A possible connection with
string theory is considered. The duality is emphasized by a minor
change in the title. The new title is: Duality of and and a
statistical interpretation of space in quantum mechanic
Spin-Coated vs. Electrodeposited Mn Oxide Films as Water Oxidation Catalysts
Manganese oxides (MnOx), being active, inexpensive and low-toxicity materials, are considered promising water oxidation catalysts (WOCs). This work reports the preparation and the physico-chemical and electrochemical characterization of spin-coated (SC) films of commercial Mn2O3, Mn3O4 and MnO2 powders. Spin coating consists of few preparation steps and employs green chemicals (i.e., ethanol, acetic acid, polyethylene oxide and water). To the best of our knowledge, this is the first time SC has been used for the preparation of stable powder-based WOCs electrodes. For comparison, MnOx films were also prepared by means of lectrodeposition (ED) and tested under the same conditions, at neutral pH. Particular interest was given to -Mn2O3-based films, since Mn (III) species play a crucial role in the electrocatalytic oxidation of water. To this end, MnO2-based SC and ED films were calcined at 500 C, in order to obtain the desired -Mn2O3 crystalline phase. Electrochemical impedance spectroscopy (EIS) measurements were performed to study both electrode charge transport properties and electrodeâelectrolyte charge transfer kinetics. Long-term stability
tests and oxygen/hydrogen evolution measurements were also made on the highest-performing samples and their faradaic efficiencies were quantified, with results higher than 95% for the Mn2O3 SC film, finally showing that the SC technique proposed here is a simple and reliable method to study the electrocatalytic behavior of pre-synthesized WOCs powders
Spin-Coated vs. Electrodeposited Mn Oxide Films as Water Oxidation Catalysts
Manganese oxides (MnOx), being active, inexpensive and low-toxicity materials, are considered promising water oxidation catalysts (WOCs). This work reports the preparation and the physico-chemical and electrochemical characterization of spin-coated (SC) films of commercial Mn2O3, Mn3O4 and MnO2 powders. Spin coating consists of few preparation steps and employs green chemicals (i.e., ethanol, acetic acid, polyethylene oxide and water). To the best of our knowledge, this is the first time SC has been used for the preparation of stable powder-based WOCs electrodes. For comparison, MnOx films were also prepared by means of lectrodeposition (ED) and tested under the same conditions, at neutral pH. Particular interest was given to -Mn2O3-based films, since Mn (III) species play a crucial role in the electrocatalytic oxidation of water. To this end, MnO2-based SC and ED films were calcined at 500 C, in order to obtain the desired -Mn2O3 crystalline phase. Electrochemical impedance spectroscopy (EIS) measurements were performed to study both electrode charge transport properties and electrode-electrolyte charge transfer kinetics. Long-term stability tests and oxygen/hydrogen evolution measurements were also made on the highest-performing samples and their faradaic efficiencies were quantified, with results higher than 95% for the Mn2O3 SC film, finally showing that the SC technique proposed here is a simple and reliable method to study the electrocatalytic behavior of pre-synthesized WOCs powders
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