Thermodynamic excess quantities in the adsorption of sodium alkylsulfonates at the air-solution interface

Colloid and Polymer Science - Data on the surface tension of sodium alkylsulfonate solutions at different temperatures and surfactant concentrations are presented. By applying the thermodynamic...     

Approximation in Hardy spaces

Summary We prove direct and converse theorems of approximation for distributions in the Hardy spaces H^p, 0相似文献   

Photostability of a photochromic naphthopyran dye in different sol-gel prepared ormosil coatings

A photochromic naphthopyran derivative was embedded in sol-gel prepared thin ormosil films. The resulting samples show high transparency and exhibit a strong red colouration upon irradiation with UV light. The photostability of the photochromic molecules is strongly related to the nature of the embedding ormosil matrix. The introduction of organic functional groups into the inner pore surface of the matrix allows tailoring the chemical environment where the dye molecules will be allocated, in terms of the effectiveness of the interaction between the photochromic molecules and the Si-OH groups on the surface of the pores, affecting the stability of the molecules upon prolonged exposition to UV light. The photostability of the molecules was increased in matrices functionalized with larger organic groups, or with larger amount of modifying groups. In this way the photodegradation of the photochromic molecules could be reduced by a factor of 5, as compared with the photodegradation of the molecules in unfunctionalized silica matrix.     

Semiempirical study of electronic and bonding properties of cobalt silicide clusters

The electronic structure of cobalt silicide clusters Co₇Si₇ and Si₇Co₇ was studied in comparison to that of Co₁₉ and Si₁₇ clusters under the scope of the MINDO/SR method. Clusters Co₇Si₇ and Si₇Co₇ represent the environment of a cobalt atom and that of a silicon atom in the cobalt monosilicide bulk, respectively. It is found that the Co? Si bond is essentially sp in character with an indirect participation (by electrostatic interaction) of the cobalt d orbitals. Our calculations show a charge transfer from silicon to the d orbitals of cobalt via sp–sp interaction with an internal sp–d hybridization. The theoretical density of states for cobalt silicide clusters are reported and compared with experimental results of surface spectroscopies. © 1992 by John Wiley & Sons, Inc.     

Novel Iron Oxide Nanoparticles Induce Ferroptosis in a Panel of Cancer Cell Lines

The use of nanomaterials rationally engineered to treat cancer is a burgeoning field that has reported great medical achievements. Iron-based polymeric nano-formulations with precisely tuned physicochemical properties are an expanding and versatile therapeutic strategy for tumor treatment. Recently, a peculiar type of regulated necrosis named ferroptosis has gained increased attention as a target for cancer therapy. Here, we show for the first time that novel iron oxide nanoparticles coated with gallic acid and polyacrylic acid (IONP–GA/PAA) possess intrinsic cytotoxic activity on various cancer cell lines. Indeed, IONP–GA/PAA treatment efficiently induces ferroptosis in glioblastoma, neuroblastoma, and fibrosarcoma cells. IONP–GA/PAA-induced ferroptosis was blocked by the canonical ferroptosis inhibitors, including deferoxamine and ciclopirox olamine (iron chelators), and ferrostatin-1, the lipophilic radical trap. These ferroptosis inhibitors also prevented the lipid hydroperoxide generation promoted by the nanoparticles. Altogether, we report on novel ferroptosis-inducing iron encapsulated nanoparticles with potent anti-cancer properties, which has promising potential for further in vivo validation.     

Analysis of Organic Compounds in Antarctic Snow and Their Origin

Abstract

Organic compounds extractable with n-hexane were identified and quantitatively determined in pack, surface and deep snow samples taken at different depths and collected at several altitudes above sea level from Antarctica during the 1993/94 Italian expedition. The comparison between the composition of organic compounds in snow and the ones in pack and sea-water samples pointed out that the three matrices substantially contain the same biogenic and anthropogenic organic compounds. The contribution of marine aerosol to organic content in the snow is confirmed by the enrichment ratios calculated for the more representative classes of identified compounds (n-alkanes, phthalates and low molecular weight alkylbenzenes). The changes in the composition of organic compounds in snow as the altitude increases seem to depend on the dimensional spectrum of the aerosol. Thus, smallest particles, richest in surfactant material, reach the highest altitudes.     

Thermal photon production in a strongly coupled anisotropic plasma

Journal of High Energy Physics - For the homogeneous configuration given by the long string limit of the folded string with a spin in AdS 3 and a spin and a winding number in S 1, we solve the...     

One-Pot Synthesis and Applications of N-Heteroaryl Iodonium Salts

An efficient one-pot synthesis of N-heteroaryl iodonium triflates from the corresponding N-heteroaryl iodide and arene has been developed. The reaction conditions resemble our previous one-pot syntheses, with suitable modifications to allow N-heteroaryl groups. The reaction time is only 30 min, and no anion exchange is required. The obtained iodonium salts were isolated in a protonated form, these salts can either be employed directly in applications or be deprotonated prior to use. The aryl groups were chosen to induce chemoselective transfer of the heteroaryl moiety to various nucleophiles. The reactivity and chemoselectivity of these iodonium salts were demonstrated by selectively introducing a pyridyl moiety onto both oxygen and carbon nucleophiles in good yields.     

A New Series of Aryloxyacetic Acids Endowed with Multi-Target Activity towards Peroxisome Proliferator-Activated Receptors (PPARs), Fatty Acid Amide Hydrolase (FAAH), and Acetylcholinesterase (AChE)

A new series of aryloxyacetic acids was prepared and tested as peroxisome proliferator-activated receptors (PPARs) agonists and fatty acid amide hydrolase (FAAH) inhibitors. Some compounds exhibited an interesting dual activity that has been recently proposed as a new potential therapeutic strategy for the treatment of Alzheimer’s disease (AD). AD is a multifactorial pathology, hence multi-target agents are currently one of the main lines of research for the therapy and prevention of this disease. Given that cholinesterases represent one of the most common targets of recent research, we decided to also evaluate the effects of our compounds on the inhibition of these specific enzymes. Interestingly, two of these compounds, (S)-5 and 6, showed moderate activity against acetylcholinesterase (AChE) and even some activity, although at high concentration, against Aβ peptide aggregation, thus demonstrating, in agreement with the preliminary dockings carried out on the different targets, the feasibility of a simultaneous multi-target activity towards PPARs, FAAH, and AChE. As far as we know, these are the first examples of molecules endowed with this pharmacological profile that might represent a promising line of research for the identification of novel candidates for the treatment of AD.