Search results for "performance"

Ecosystem Adversity as Setting Factors in Mothers' Judgment of Child Behavior and Indiscriminate Mothering

1996

Several studies have shown that troubled mothers are not accurate observers of their children's behavior. These mothers have a global and usually blame-oriented reporting style coloured by disphoric views of social isolation, social coercion and socioeconomic disadvantage. The dsyphoric view describes a number of contextual or setting factors that seem to influence a mother's observational reports about her child more than the child's actual behavior does. Of course, when this observational bias exists, the mother's parenting performance is bound to be comprised. According to the considerations above, this study was designed with a group of 21 mother-child dyads characterized by their coer…

Management in China: Cultural, institutional roots and pragmatism. An inquiry in Shanghai

2015

We base our work on interviews of Chinese managers living in and around Shanghai. We use the neo-institutional theoretical stream, which considers that a country’s economy is influenced by cultural and institutional phenomena. In a first part, we describe the theoretical background to the research and our method. Then, in a second part, we present the significant cultural and institutional features of China that enable us to justify several hypotheses about our topic. In a third part, we analyze eight in-depth interviews, trying to answer our research question. Our basic research question focuses on what “Performance” means for Chinese managers. Behind the word, we analyze the cultural and …

BONDED SILICA PHASES FOR THE SEPARATION OF BIOPOLYMERS BY MEANS OF COLUMN LIQUID CHROMATOGRAPHY

1988

Is multidimensional high performance liquid chromatography (HPLC) an alternative in protein analysis to 2D gel electrophoresis?

2000

The interactive modes of High Performance Liquid Chromatography (HPLC) of proteins provide a platform for the construction of a multidimensional HPLC system coupled to mass spectrometry. We present a system composed of both anion and cation exchanger columns, in the first dimension, and n-octadecyl bonded 1.5 μm nonporous silica columns in the second dimension. Both columns are operated under gradient conditions. A system suitability test with standard proteins showed that the total analysis can be performed within about 20 minutes. The fractions taken from the ion exchanger column are directly analyzed within one minute on the reversed phase column at a high flow rate. Two reversed phase c…

Modulation of the growth and metabolic response of cyanobacteria by the multifaceted activity of naringenin

2017

The interactions between the plant-derived bioflavonoid, naringenin, and prokaryotic microalgae representatives (cyanobacteria), were investigated with respect to its influence on the growth and metabolic response of these microorganisms. To achieve reliable results, the growth of cyanobacteria was determined based on measurements of chlorophyll content, morphological changes were assessed through microscopic observations, and the chemical response of cells was determined using liquid and gas chromatography (HPLC; GC-FID). The results show that micromolar levels of naringenin stimulated the growth of cyanobacteria. Increased growth was observed for halophilic strains at naringenin concentra…

Microscale synthesis of phosphatidyl-[3H]choline from 1,2-diacylglycerol. Assessment of isomerization by reversed-phase high-performance liquid chrom…

1995

The synthesis of rac-1-palmitoyl-2-oleoylglycero-3-phospho-[3H]choline of high specific activity was carried out on a microscale by making 7 mumol of rac-1-palmitoyl-2-oleoylglycerol react first with an equimolar amount of POCl3 and then of [3H]choline. After purification by thin-layer chromatography and normal-phase high-performance liquid chromatography and normal-phase high-performance liquid chromatography (HPLC), the yield of the synthesis of [3H]phosphatidylcholine (120 microCi/mumol) was 22%. rac-1-Palmitoyl-2-oleoylglycerol was purified before use by reversed-phase HPLC under conditions which were nonisomerizing and allowed the separation of 1,2- and 1,3-isomers of diacylglycerol. E…

Analysis of eicosapentaenoic and docosahexaenoic acid geometrical isomers formed during fish oil deodorization.

2006

International audience; Addition of long-chain polyunsaturated fatty acids (LC-PUFAs) from marine oil into food products implies preliminary refining procedures of the oil which thermal process affects the integrity of LC-PUFAs. Deodorization, the major step involving high temperatures, is a common process used for the refining of edible fats and oils. The present study evaluates the effect of deodorization temperature on the formation of LC-PUFA geometrical isomers. Chemically isomerized eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were used as reference samples. Fish oil samples have been deodorized at 180, 220 and 250 °C for 3 h and pure EPA and DHA fatty acid methyl esters…

Performance of short-chain alcohols versus acetonitrile in the surfactant-mediated reversed-phase liquid chromatographic separation of β-blockers

2010

Organic solvents are traditionally added to micellar mobile phases to achieve adequate retention times and peak profiles, in a chromatographic mode which has been called micellar liquid chromatography (MLC). The organic solvent content is limited to preserve the formation of micelles. However, at increasing organic solvent contents, the transition to a situation where micelles do not exist is gradual. Also, there is no reason to neglect the potentiality of mobile phases containing only surfactant monomers instead of micelles (high submicellar chromatography, HSC). This is demonstrated here for the analysis of β-blockers. The performance of four organic solvents (methanol, ethanol, 1-propano…

Review: Determination of Vitamin D in Dairy Products by High Performance Liquid Chromatography

2005

This work reviews the methods used for the determination of vitamin D in some dairy products (milk and infant formulas) by high performance liquid chromatography (HPLC). The low vitamin D contents and the presence of interfering compounds require sample treatment and purification of the extract. The advantages and drawbacks of hot and cold saponification, direct extraction and different types of extract purification are also discussed, taking into account the lack of vitamin D stability by heating, exposure to light and oxidation. With respect to chromatographic determination, the mode (normal or reverse phase), type of column (microcolumn or conventional) and detection system (UV, electro…

Eucalyptol-based green extraction of brown alga Zonaria tournefortii

2018

Abstract A green extraction method, based on the use of 1,8-cineole (eucalyptol) as biosolvent, has been developed to prepare crude extracts from the brown alga Zonaria tournefortii characterized by chemical composition, particularly dominated by phenolic compounds derived from phloroglucinol. The main advantage of the developed technique are the recovery of eucalyptol, based on multistep liquid-liquid extraction with distilled water, followed by centrifugation and elimination of the aqueous phase, and the complete recycling of biosolvent by steam distillation. A comparative study between the proposed green extract and the conventional extract, prepared by solvent maceration using the mixtu…