The Alexander-Orbach conjecture holds in high dimensions

We examine the incipient infinite cluster (IIC) of critical percolation in regimes where mean-field behavior has been established, namely when the dimension d is large enough or when d>6 and the lattice is sufficiently spread out. We find that random walk on the IIC exhibits anomalous diffusion with the spectral dimension d_s=\frac43d_{s}=\frac{4}{3} , that is, p _t (x,x)=t ^−2/3+o(1). This establishes a conjecture of Alexander and Orbach (J. Phys. Lett. (Paris) 43:625–631, 1982). En route we calculate the one-arm exponent with respect to the intrinsic distance.     

New chiral selenium electrophiles derived from functionalized terpenes

A convenient method for the synthesis of optically active dialkyl diselenides derived from bicyclic terpenes functionalized with hydroxy, etheral, sulfide, and selenide groups is described. The diselenides were used for a synthesis of chiral electrophilic selenium reagents, then in the asymmetric selenenylation of styrene and selenocyclization with o-allylphenol. The influence of nonbonding selenium-heteroatom interactions in the generated organoselenium electrophiles on the stereoselectivity of an addition reaction has been investigated. Calculations by a DFT method on a B3LYP (6-311G (d)) level, confirmed the existence of nonbonded selenium-heteroatom interactions in the investigated systems.     

Silver‐Triggered Activity of a Heterogeneous Palladium Catalyst in Oxidative Carbonylation Reactions

A silver‐triggered heterogeneous Pd‐catalyzed oxidative carbonylation has been developed. This heterogeneous process exhibits high efficiency and good recyclability, and was utilized for the one‐pot construction of polycyclic compounds with multiple chiral centers. AgOTf was used to remove chloride ions in the heterogeneous catalyst Pd‐AmP‐CNC, thereby generating highly active Pd^II, which results in high efficiency of the heterogeneous catalytic system.     

Silver-Triggered Activity of a Heterogeneous Palladium Catalyst in Oxidative Carbonylation Reactions

A silver-triggered heterogeneous Pd-catalyzed oxidative carbonylation has been developed. This heterogeneous process exhibits high efficiency and good recyclability, and was utilized for the one-pot construction of polycyclic compounds with multiple chiral centers. AgOTf was used to remove chloride ions in the heterogeneous catalyst Pd-AmP-CNC, thereby generating highly active Pd^II, which results in high efficiency of the heterogeneous catalytic system.     

Tissue sample preparations for preclinical research determined by molecular imaging mass spectrometry using matrix-assisted laser desorption/ionization

Matrix-assisted laser desorption/ionization - imaging mass spectrometry is an alternative tool, which can be implemented in order to obtain and visualize the “omic” signature of tissue samples. Its application to clinical study enables simultaneous imaging-based morphological observations and mass spectrometry analysis. Application of fully informative material like tissue allows obtaining the complex and unique profile of analyzed samples. This knowledge leads to diagnosing disease, studying the mechanism of cancer development, selecting the potential biomarkers as well as correlating obtained images with prognosis. Nevertheless, it is worth noticing that this method is found to be objective but the result of the analysis is mainly influenced by the sample preparation protocol, including the collection of biological material, its preservation, and processing. However, the application of this approach requires a special sample preparation procedure. The main goal of the study is to present the current knowledge on the clinical application of matrix-assisted laser desorption/ionization with imaging mass spectrometry in cancer research, with particular emphasis on the sample preparation step. For this purpose, several protocols based on cryosections and formalin-fixed paraffin-embedded tissue were compiled and compared, taking into account the measured metabolites of potential diagnostic importance for a given type of cancer.     

Coherent Surface Plasmon Hole Burning via Spontaneously Generated Coherence

Surface plasmon (SP)—induced spectral hole burning (SHB) at the silver-dielectric interface is investigated theoretically. We notice a typical lamb dip at a selective frequency, which abruptly reduces the absorption spectrum of the surface plasmons polaritons (SPP). Introducing the spontaneous generated coherence (SGC) in the atomic medium, the slope of dispersion becomes normal. Additionally, slow SPP propagation is also noticed at the interface. The spectral hole burning dip is enhanced with the SGC effect and can be modified and controlled with the frequency and intensity of the driving fields. The SPP propagation length at the hole-burning region is greatly enhanced under the effect of SGC. A propagation length of the order of 600 µm is achieved for the modes, which is a remarkable result. The enhancement of plasmon hole burning under SGC will find significant applications in sensing technology, optical communication, optical tweezers and nano-photonics.     

A new four-parameter empirical potential energy function for diatomic molecules

A new empirical four-parameter function is proposed for the construction of potential curves of 15 stable states of diatomic molecules. The parameters are evaluated in terms of experimentally known spectroscopic constants. On comparing its performance with other functions, the proposed function is found to be simple and reliable for a wide range of molecules.      

Intensity discrimination with gated and continuous sinusoids

Detectability of sinusoidal signals at several durations was measured in the presence of sinusoidal maskers of the same frequency. Maskers were either continuous or gated on and off with the signal. For all signal durations and both types of maskers, delta I/I varied with I raised to the -0.1 power, approximately. Psychometric functions were two or three times steeper with continuous than with gated maskers. Signal duration had only a small effect that varied with the masking condition.