Search for critical fluctuations of the proton density in central A+A collisions at maximum SPS energy

We performed an intermittency analysis of the proton density fluctuations in transverse momentum space for the collisions Si+A (A=Al,Si,P) and C+A (A=C,N) at maximum SPS energy $\sqrt {s_{NN} } $ ?? 17 GeV). In our analysis we used exclusively proton tracks in the midrapidity region (|y _CM | ?? 0.75). For the Si+A system we find signature of power-law distributed density fluctuations quantified by the intermittency index ? ₂ which approaches in size the predictions of critical QCD [Phys. Rev. Lett. 97, 032002 (2006)]. This result supports further the recent findings of power-law fluctuations in the density of (?? ⁺, ?? ^?) pairs with invariant mass close to their production threshold for the Si+Si at the same energy, reported in [Phys. Rev. C 81, 064907 (2010)].     

Flow Potentiometric Injection Analysis of Uric Acid Using Lipid Stabilized Films with Incorporated Uricase on ZnO Nanowires

A novel potentiometric uric acid biosensor was fabricated by immobilization of uricase into stabilized lipid films using zinc oxide (ZnO) nanowires as measuring electrode. Uricase was incorporated into the lipid film prior polymerization on the surface of well aligned ZnO nanowires resulting in a sensitive, selective, stable and reproducible uric acid biosensor. The potentiometric response was twice as large from previously reported values due to the presence of a cationic lipid in the lipid film. The sensor response had no interferences by normal concentrations of ascorbic acid, glucose, urea, proteins and lipids.     

Periodic lattice-ordered pregroups are distributive

It is proved that any lattice-ordered pregroup that satisfies an identity of the form x ^ll···l = x ^rr···r (for the same number of ^l,r -operations on each side) has a lattice reduct that is distributive. It follows that every such ?-pregroup is embedded in an ?-pregroup of residuated and dually residuated maps on a chain.     

Chemical bonding of chlorophylls and plant aminic axial ligands impact harvesting of visible light and quenching of fluorescence

In the present work, we tested the mode of interaction of all three polyamines (putrescine, spermidine and spermine) with chlorophyll a and b, as well as pheophytin a and b. The results showed that all three polyamines bind to the Mg ion of chlorophyll ring as probed by Raman spectroscopy. The coordination of spermine with Chl b has the most interesting features from all pigments tested. Spermine induces reversible increases and decreases of the fluorescence yield of Chl b at about 661 nm. Interestingly, equilibrium between a high-fluorescence yield conformation and a low yield is feasible by the interaction of chlorophyll b and aminic ligands. Furthermore, absorption data for the diagnostic regions of 518 and 535 nm are provided for all combinations of pigments and ligands. The significance and consistence of these results with respect to photochemical and bioenergetic principles are discussed.     

Constant sign and nodal solutions for logistic-type equations with equidiffusive reaction

We consider a logistic-type equation driven by the p-Laplace differential operator with an equidiffusive reaction term. Combining variational methods based on critical point theory together with truncation techniques and Morse theory, we show that when ?? > ??₁, the problem has extremal solutions of constant sign and when ?? > ??₂ it has also a nodal (sign-changing) solution. Here ??₁?<???₂ are the first two eigenvalues of the negative Dirichlet p-Laplacian. In the semilinear case (i.e. p?=?2) we produce two nodal solutions.     

A deterministic resource scheduling model in epidemic control: A case study

The resources available to tackle an epidemic infection are usually limited, while the time and effort required to control it are increasing functions of the starting time of the containment effort. The problem of scheduling limited available resources, when there are several areas where the population is infected, is considered. A deterministic model, appropriate for large populations, where random interactions can be averaged out, is used for the epidemic’s rate of spread. The problem is tackled using the concept of deteriorating jobs, i.e. the model represents increasing loss rate as more susceptibles become infected, and increasing time and effort needed for the epidemic’s containment. A case study for a proposed application of the model in the case of the mass vaccination against A(H1N1)_v influenza in the Attica region, Greece and a comparative study of the model’s performance vs. the applied random practice are presented.     

Ultrasound assisted catalytic wet peroxide oxidation of phenol: kinetics and intraparticle diffusion effects

The combination of ultrasound irradiation and catalytic wet peroxide oxidation was used as a means to degrade phenol. Direct and indirect irradiation were employed, while experiments in the absence of ultrasound were used as reference. A mixed (Al-Fe) pillared clay named FAZA, was used as a catalyst in the form of powder, extrudates and crushed extrudates. Ultrasound was found to clearly enhance the extrudates performance, increasing the conversion at 4h by more than 6 times under direct and almost 11 times under indirect irradiation. This observation is attributed to the reduction of diffusion resistance within the catalyst pores. The overall sonication-catalytic wet peroxide oxidation process appears very promising for environmental purposes.     

Development of a novel method based on liquid chromatography-evaporative light scattering detection for the direct determination of streptomycin and dihydrostreptomycin in raw materials, pharmaceutical formulations, culture media and plasma

A novel method for the non-derivatization liquid chromatographic determination of streptomycin (STR) and dihydrostreptomycin (DHSTR) was developed and validated based on evaporative light scattering detection (ELSD). Utilizing a ThermoHypersil BetaBasic C18 analytical column, evaporation temperature of 50 degrees C and pressure of nebulizing gas (nitrogen) of 3.5 bar, the optimized mobile phase was 1.25 mL L(-1) TFA aqueous solution, in an isocratic mode at a rate of 1.0 mL min(-1). STR was eluted at 5.6 min and DHSTR at 7.8 min with a resolution of 4.4. Linear calibration curves were obtained from 2 to 120 microg mL(-1) (r > 0.9990) for STR and 2-75 microg mL(-1) (r > 0.9994) for DHSTR, with a LOD equal to 0.7 and 0.5 microg mL(-1), respectively. The developed method was applied for the assay of STR and DHSTR (sulfate) in pharmaceutical raw materials and formulations, while the simultaneous direct determination of sulfate was feasible (tR = 2.5 min, LOD = 1.4 microg mL(-1), double logarithmic calibration curve in the range of 4-50 microg mL(-1), r > 0.9998). Modified isocratic mobile phase (H2O-ACN, 90:10, v/v, containing 1.25 mL L(-1) TFA), was used for the determination of streptomycin B impurity in STR sulfate raw material and a gradient mobile phase (H2O-ACN containing TFA) was used for the determination of DHSTR in the presence of penicillinG procaine. The developed method was also applied for the assay of commercial formulations (STR powder and DHSTR injection solution and suspension) (%recovery 98-102, %RSD < 1.3, n = 3 x 3), for the determination of STR in bacteria culture medium (%recovery 99.6, %RSD = 0.8, n = 3 x 3), and for the determination of DHSTR in human plasma (2.0-23.0 microg mL(-1)) after solid phase extraction using carboxylate cartridges (%recovery 98.4-101.8, %RSD = 3.2, n = 3 x 3).     

p-convergence in measure of a sequence of measurable functions and corresponding minimal elements of c 0

We characterize convergence in measure of a sequence (f_n)_n of measurable functions to a measurable function f by elements of c₀, which express the quality of convergence of (f_n)_n to f. This characterization motivates the introduction of a new notion of convergence, called “p-convergence in measure” (p > 0), which is stronger than convergence in measure. We prove the existence of “minimal” elements in c₀ which characterize the convergence in measure of (f_n)_n to f.