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Green processes based on the extraction with pressurized fluids to obtain potent antimicrobials from Haematococcus pluvialis microalgae

In the present work, the antimicrobial activity of different pressurized liquid extracts obtained from Haematococcus pluvialis microalga was tested against several microorganisms of importance for the food industry (Escherichia coli, Staphylococcus aureus, Candida albicans and Aspergillus niger). Extractions were performed with hexane and ethanol at four different temperatures (50, 100, 150 and 20

A systematic study on the interactions between carnosic acid and ethylpyrrolidine methacrylate-methyl methacrylate copolymer in supercritical media

In the present work, a systematic study on the interactions between carnosic acid (potent natural antioxidant from rosemary) and ethylpyrrolidine methacrylate-methyl methacrylate (EPyM/MMA) copolymer (synthesized in our laboratory) has been performed using different spectroscopic and thermogravimetric techniques. By comparing data obtained for the reference sample (carnosic acid + copolymer) with

Predicting progression to dementia in persons with mild cognitive impairment using cerebrospinal fluid markers

Introduction: We aimed to determine the added value of cerebrospinal fluid (CSF) to clinical and imaging tests to predict progression from mild cognitive impairment (MCI) to any type of dementia. Methods: The risk of progression to dementia was estimated using two logistic regression models based on 250 MCI participants: the first included standard clinical measures (demographic, clinical, and ima

Angle resolved photoelectron spectroscopy of two-color XUV-NIR ionization with polarization control

Electron emission caused by extreme ultraviolet (XUV) radiation in the presence of a strong near infrared (NIR) field leads to multiphoton interactions that depend on several parameters. Here, a comprehensive study of the influence of the angle between the polarization directions of the NIR and XUV fields on the two-color angle-resolved photoelectron spectra of He and Ne is presented. The resultin

A new formulation and analysis of a collapsing bubble with different content in a liquid induced during acoustic cavitation

Purpose - The purpose of this paper is to present numerical investigation of the gas/vapor bubble dynamics under the influence of an ultrasonic field to give a more comprehensive understanding of the phenomenon and present new results Design/methodology/approach - In order to formulate the mathematical model, a set of governing equations for the gas inside the bubble and the liquid surrounding it

Automated determination of Vinclozolin at the ppb level in aqueous samples by a combination of microporous membrane liquid-liquid extraction and adsorption chromatography

An automated system with microporous membrane liquid-liquid extraction (MMLLE) combined with HPLC has been designed for the determination of Vinclozolin in aqueous matrices. In MMLLE a porous hydrophobic membrane separates an aqueous phase from an organic phase. The pores are filled with the organic solvent. In this work, MMLLE was performed in a flow system and coupled on-line to normal phase HPL

Long-Term Studies of Fungicide Concentrations in Greenhouses. 1. Technique for Determining Surficial Foliar Residues of Fungicides with Vinclozolin and Triadimefon as Model Compounds.

A new analysis procedure for fungicides has been developed gearing toward estimation of worker exposure in greenhouses. The procedure includes sampling on leaves, glass, and polymers using vinclozolin and triadimefon as model substances and starts with solvation of the fungicides with ethanol from the surface. It proceeds by collection of the solution on disks of cloth, disk extraction with excess

Specific effects of platelet derived growth factor (PDGF) on fetal rat and human dopaminergic neurons in vitro

The neurotrophic effects of the BB isoform of platelet-derived growth factor (PDGF) on rat and human fetal mesencephalic dopaminergic neurons have been characterized in vitro. A dose-response analysis demonstrated maximal responses at 30 ng/ml of PDGF-BB. This concentration resulted in a marked increase in the survival and neurite outgrowth from rat and human tyrosine hydroxylase-(TH) positive, pr

Coherent two-dimensional spectroscopy of a Fano model

The Fano line shape arises from the interference of two excitation pathways to reach a continuum. Its generality has resulted in a tremendous success in explaining the line shapes of many one-dimensional spectroscopies - absorption, emission, scattering, conductance, photofragmentation - applied to very varied systems - atoms, molecules, semiconductors, and metals. Unraveling a spectroscopy into a

Academic Entrepreneurship and Exchange of Scientific Resources : Material Transfer in Life and Materials Sciences in Japanese Universities

This study uses a sample of Japanese university scientists in life and materials sciences to examine how academic entrepreneurship has affected the norms and behaviors of academic scientists regarding sharing scientific resources. Results indicate that high levels of academic entrepreneurship in a scientific field are associated with less reliance on the gift-giving form of sharing (i.e., generali

Metal-passivated PbS nanoparticles : Fabrication and characterization

Organic-shell-free PbS nanoparticles have been produced in the size range relevant for quantum-dot solar cells (QDSCs) by a vapor aggregation method involving magnetron reactive sputtering. This method creates a beam of free 5-10 nm particles in a vacuum. The dimensions of the particles were estimated after their deposition on a substrate by imaging them using ex situ SEM and HRTEM electron micros

Use of dissertation data in science policy research

Although the contribution of scientometric literature to policies on academic science has been substantial, the literature has focused primarily on the production of scientific knowledge, whereas limited attention has been paid to the other critical mission of academic institutions, i.e., education or the production of scientists. To address this limitation and better inform policymakers, the curr