Stochastically weighted stochastic dominance concepts with an application in capital budgeting

The problem of comparing random vectors arises in many applications. We propose three new concepts of stochastically weighted dominance for comparing random vectors X and Y. The main idea is to use a random vector V to scalarize X and Y   as V^TX$V^{T}X$ and V^TY$V^{T}Y$, and subsequently use available concepts from stochastic dominance and stochastic optimization for comparison. For the case where the distributions of X, Y and V have finite support, we give (mixed-integer) linear inequalities that can be used for random vector comparison as well as for modeling of optimization problems where one of the random vectors depends on decisions to be optimized. Some advantages of the proposed new concepts are illustrated with the help of a capital budgeting example.     

Synchrotron μ‐XRF study on compositional uniformity of uranium–thorium oxide pellets prepared by different processes

A μ‐XRF study to assess the distribution of uranium and thorium in (U,Th)O₂ pellets covering the composition of advanced heavy water reactor (AHWR) fuel pellets prepared by powder metallurgical compaction (PMC) and coated agglomerate pelletization (CAP) routes was made using micro‐focus beam line (BL‐16) of Indus‐2 synchrotron radiation facility. The methodology thus developed was successfully applied to these pellets. The study reveals that the uranium distribution in pellets prepared by PMC route is uniform, whereas the pellets prepared through CAP route have a wide range of compositional variation. In addition, the uniformity in CAP route‐prepared pellets improves with increase in the relative amount of uranium in the pellets. The sample preparation in present methodology is very simple compared with scanning electron microscopy. The study reveals the utility of synchrotron‐based μ‐XRF for fuel pellet characterization of AHWR reactors. Alhough CAP route of fuel pellet preparation requires less exposure of personnel to high radiation dose, the non‐uniformity in the fuel pellet must be considered when using these pellets in reactors. Copyright © 2014 John Wiley & Sons, Ltd.     

Qualitative inequalities for squared partial correlations of a Gaussian random vector

We describe various sets of conditional independence relationships, sufficient for qualitatively comparing non-vanishing squared partial correlations of a Gaussian random vector. These sufficient conditions are satisfied by several graphical Markov models. Rules for comparing degree of association among the vertices of such Gaussian graphical models are also developed. We apply these rules to compare conditional dependencies on Gaussian trees. In particular for trees, we show that such dependence can be completely characterised by the length of the paths joining the dependent vertices to each other and to the vertices conditioned on. We also apply our results to postulate rules for model selection for polytree models. Our rules apply to mutual information of Gaussian random vectors as well.     

Design and Synthesis of a Pyridine Based Chemosensor: Highly Selective Fluorescent Probe For Pb2+

A pyridine based imine-linked chemosensor has been synthesized and evaluated its binding affinity with library of transition metal ions. It has prominent selectivity towards Pb²⁺ among other metal ions in DMF/H₂O (9:1, v/v) solvent system. The 1:1 stoichiometric was confirmed by job’s plot and has a binding constant (K_a)?=?5.142?×?10³ M^?1 on fluorescence. A B3LYP/6-31G and B3LYP/LanL2DZ basis sets were employed for optimization of 3 and 3.Pb²⁺.     

Urea Based Dipodal Fluorescence Receptor for Sensing of Fe3+ Ion in Semi-Aqueous Medium

Urea based fluorescent chemosensor 1 was synthesized. Receptor 1 shows unique selectivity for the Fe³⁺ion and no such significant response was noticed with other metal ions (Cr³⁺, Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺, Zn²⁺, Cd²⁺, Hg²⁺, Pb²⁺ and Bi³⁺) in DMSO/H₂O (50:50,v/v) semi-aqueous solution. The binding features have been established by absorption and fluorescence spectroscopic methods. The binding constant (K) values obtained from Benesi-Hildebrand, Scatchard and Connor plot for receptor 1 is (8.3?±?0.3) × 10³ M^?1 and has good detection limit 0.7?μM. The stoichiometry of 1.Fe³⁺ complex was confirmed by mass spectroscopy and Job’s plot.

Effect of Salts (NaCl and Na2CO3) on Callus and Suspension Culture of Stevia rebaudiana for Steviol glycoside Production

Steviol glycosides are natural non-caloric sweeteners which are extracted from the leaves of Stevia rebaudiana plant. Present study deals the effect of salts (NaCl and Na₂CO₃) on callus and suspension culture of Stevia plant for steviol glycoside (SGs) production. Yellow-green and compact calli obtained from in vitro raised Stevia leaves sub-cultured on MS medium supplemented with 2.0 mg l^?1 NAA and different concentrations of NaCl (0.05–0.20 %) and Na₂CO₃ (0.0125–0.10 %) for 2 weeks, and incubated at 24?±?1 °C and 22.4 μmol m^?2 s^?1 light intensity provided by white fluorescent tubes for 16 h. Callus and suspension biomass cultured on salts showed less growth as well as browning of medium when compared with control. Quantification of SGs content in callus culture (collected on 15th day) and suspension cultures (collected at 10th and 15th days) treated with and without salts were analyzed by HPLC. It was found that abiotic stress induced by the salts increased the concentration of SGs significantly. In callus, the quantity of SGs got increased from 0.27 (control) to 1.43 and 1.57 % with 0.10 % NaCl, and 0.025 % Na₂CO₃, respectively. However, in case of suspension culture, the same concentrations of NaCl and Na₂CO₃ enhanced the SGs content from 1.36 (control) to 2.61 and 5.14 %, respectively, on the 10th day.     

A facile route to the synthesis of pyrimido[2,1-b]quinazoline core from the primary allyl amines afforded from Baylis–Hillman adducts

A highly simplified approach for the generation of substituted pyrimido[2,1-b]quinazoline core from the primary allyl amines afforded from the Baylis–Hillman adducts is described. Sequential reductive alkylation of the primary allyl amine with 2-nitrobenzaldehyde, reduction of the aromatic nitro group with In, CNBr-promoted intramolecular cyclization followed by NaOMe-mediated another intramolecular cyclization furnish the title compounds.     

Combination of 5-Fluorouracil with Photodynamic Therapy: Enhancement of Innate and Adaptive Immune Responses in a Murine Model of Actinic Keratosis†

We previously showed that a combination of differentiation-inducing agents (5-fluorouracil [5FU], vitamin D3 or methotrexate) and aminolevulinate-based photodynamic therapy (PDT) improves clinical responses by enhancing protoporphyrin IX (PpIX) photosensitizer levels and cell death. Here, we show that in addition to its previously known effects, 5FU enhances PDT-induced tumor-regressing immunity. Murine actinic keratoses were treated with topical 5FU or vehicle for 3 days prior to aminolevulinic acid application, followed by blue light illumination (~417 nm). Lesions were harvested for time-course analyses of innate immune cell recruitment into lesions, i.e. neutrophils (Ly6G+) and macrophages (F4/80+), which peaked at 72 h and 1 week post-PDT, respectively, and were greater in 5FU-treated lesions. Enhanced infiltration of activated T cells (CD3+) throughout the time course, and of cytotoxic T cells (CD8+) at 1–2 weeks post-PDT, also occurred in 5FU-treated lesions. 5FU pretreatment reduced the presence of cells expressing the immune checkpoint marker PD-1 at ~72 h post-PDT, favoring cytotoxic T cell activity. A combination of 5FU and PDT, each individually known to induce long-term tumor-targeting immune responses in addition to their more immediate effects on cancer cells, may synergize to provide better management of squamous precancers.     

Catalytic Hydrosilylation of Imines by Aluminum Hydride Cations

In this work, the catalytic activity of electronically unsaturated three coordinated aluminum hydride cations [ L AlH]⁺[HB(C₆F₅)₃]⁻ ( 1 ) and [ L AlH]⁺[B(C₆F₅)₄]⁻ ( 2 ) in hydrosilylation of imines has been disclosed ( L ={(2,6-ⁱPr₂C₆H₃N)P(Ph₂)}₂N). A variety of organo-silanes such as Et₃SiH, MePhSiH₂, PhSiH₃, TMDSO, and PHMS are screened in this endeavour. The amines as products of catalysis were obtained in good to excellent yields after the hydrolysis of silylamine intermediates. Further, a series of controlled experiments systematically designed to investigate the underlying mechanistic pathway through multinuclear NMR analysis showed Lewis adduct formation between cationic aluminum centre and the imine nitrogen, which subsequently undergoes reaction with silane to afford the product. The hydrosilylation of imine performed with Et₃SiH using catalyst 1 with a loading of 2 mol % at 60 °C occurs smoothly. Whereas 2 led to the product formation with Et₃SiH only when used in stoichiometric quantity. Further, to investigate this unique behaviour of 1 NMR investigations were performed and revealed that the anion in 1 competes for hydride delivery and in-situ generates B(C₆F₅)₃ that cooperatively reinforces the catalytic activity of 1 .     

Complexity and synchronization in stochastic chaotic systems

We investigate the complexity of a hyperchaotic dynamical system perturbed by noise and various nonlinear speech and music signals. The complexity is measured by the weighted recurrence entropy of the hyperchaotic and stochastic systems. The synchronization phenomenon between two stochastic systems with complex coupling is also investigated. These criteria are tested on chaotic and perturbed systems by mean conditional recurrence and normalized synchronization error. Numerical results including surface plots, normalized synchronization errors, complexity variations etc show the effectiveness of the proposed analysis.