Search results for "SAMPLE"

Characterisation of disaccharide fragments from the enzymatic digestion of heparin by liquid secondary ion mass spectrometry

1988

Disaccharide fragments resulting from the enzymatic digestion of heparins with heparinase have been purified by gel filtration chromatography and directly analyzed by positive and negative ion liquid secondary ion mass spectrometry (LSIMS). Following the chromatographic purification from excess sodium salt, the mass spectra of di- and tetrasaccharide fragment mixtures enabled the identification of up to three covalently bound sulfate moieties per glycosaminoglycan-disaccharide unit, by means of their molecular ions, containing the corresponding alkali-counterions.

Molecular approach for the characterization of ancient /degraded Cyperus sp.specimens

2013

The aim of this work has been to apply and improve the efficiency of molecular tools for the identification of Cyperus sp. from difTerent sources. Total DNA was extracted from fresh, degraded and ancient specimens. DNA molecules were the template for in vitro amplification of specific target regions referred to rcbL plastid gene (ribulose-l,5 -biphosphate carboxylase/oxygenase large subunit). Dedicated DNA extraction and amplification protocols have been applied specifically for fresh/degraded and ancient samples. Particularly, specific set of primer, annealing temperatures and reaction mixtures have been performed. The PCR products, single DNA fragments, were resolved on agarose gel electr…

Testing for goodness rather than lack of fit of an X–chromosomal SNP to the Hardy-Weinberg model

2019

The problem of checking the genotype distribution obtained for some diallelic marker for compatibility with the Hardy-Weinberg equilibrium (HWE) condition arises also for loci on the X chromosome. The possible genotypes depend on the sex of the individual in this case: for females, the genotype distribution is trinomial, as in the case of an autosomal locus, whereas a binomial proportion is observed for males. Like in genetic association studies with autosomal SNPs, interest is typically in establishing approximate compatibility of the observed genotype frequencies with HWE. This requires to replace traditional methods tailored for detecting lack of fit to the model with an equivalence test…

Propiedades psicométricas del Inventario Breve de Síntomas-18 en una muestra heterogénea de pacientes de cáncer adulto

2019

espanolResumen El Inventario Breve de Sintomas-18 (BSI-18) es un instrumento de cribado ampliamente utilizado para evaluar distres emocional (GSI) y tres tipos de sintomas: ansiedad, depresion, y somatizacion. Este trabajo estudia la estructura factorial del BSI-18, utilizando analisis factorial confirmatorio (AFC), su fiabilidad y validez convergente, asi como su invarianza factorial a traves del sexo. Una muestra de 1183 pacientes de cancer completo el BSI 18 y la lista de problemas de la NCCN. Los modelos jerarquicos de tres y cuatro factores proporcionaron ajustes adecuados y similares. Sin embargo, el modelo de tres factores (propuesta teorica) fue seleccionado por razones metodologica…

Measuring dissatisfaction with coauthorship: An empirical approach based on the researchers’ perception

2019

Abstract Increasing levels of collaboration constitute one of the characteristics of science. However, the knowledge production system is based on a fundamental discordance: on the one hand, it is cooperative in nature, with links articulated through coauthorships, and on the other, the systems for assigning merit and distributing rewards function on an individual scale. This contradiction can give rise to dysfunction and inappropriate practices. This study analyses researchers’ perceptions about the problems associated with authorship in scientific publications. We make use of a coauthorship dissatisfaction index that measures the degree of dissatisfaction with the author order on the byli…

Current trends on the determination of organic UV filters in environmental water samples based on microextraction techniques – A review

2018

UV filters are a group of cosmetic ingredients commonly used in a wide variety of cosmetic products to protect users from UV solar radiation. They belong to different chemical families, such as benzophenones, p-aminobenzoates, salicylates, cinnamates, benzotriazoles, benzimidazoles, camphor derivatives, triazines, etc. These cosmetic ingredients are considered as emerging contaminants since they easily reach the aquatic environment, where they are accumulated causing harmful effects in the flora and fauna despite being present at the ng L-1 level. Therefore, the development of sensitive and selective analytical methods for their environmental surveillance monitoring is of high interest. In …

Use of Nanomaterial-Based (Micro)Extraction Techniques for the Determination of Cosmetic-Related Compounds

2020

The high consumer demand for cosmetic products has caused the authorities and the industry to require rigorous analytical controls to assure their safety and efficacy. Thus, the determination of prohibited compounds that could be present at trace level due to unintended causes is increasingly important. Furthermore, some cosmetic ingredients can be percutaneously absorbed, further metabolized and eventually excreted or bioaccumulated. Either the parent compound and/or their metabolites can cause adverse health effects even at trace level. Moreover, due to the increasing use of cosmetics, some of their ingredients have reached the environment, where they are accumulated causing harmful effec…

2016

Purpose This study assessed the prevalence of physical and cognitive doping in recreational triathletes with two different randomized response models, that is, the Cheater Detection Model (CDM) and the Unrelated Question Model (UQM). Since both models have been employed in assessing doping, the major objective of this study was to investigate whether the estimates of these two models converge. Material and Methods An anonymous questionnaire was distributed to 2,967 athletes at two triathlon events (Frankfurt and Wiesbaden, Germany). Doping behavior was assessed either with the CDM (Frankfurt sample, one Wiesbaden subsample) or the UQM (one Wiesbaden subsample). A generalized likelihood-rati…

How Effective are Business Ethics/CSR Courses in Higher Education?

2016

AbstractConcern is increasing worldwide for introducing dedicated courses on business ethics and Corporate Social Responsibility (CSR) in higher education curricula. In this study, awareness of business ethics is investigated from a sample of 307 undergraduate and postgraduate management students at a Polish university. This investigation aims at assessing management students’ awareness of business ethics issues, focusing on the potential differences in such perceptions depending on previous business ethics/CSR courses taken. Surprisingly, our results do not match prior findings in the extant literature. Notably, in our sample, having taken previous courses on business ethics/CSR does not p…

The perceived time value importance for enrolment in online masters courses: an extension of the Technology Acceptance Model

2020

Purpose. The main objective of this research is to obtain a better understanding of the impact of perceived time value on the intention of pursuing an online Master’s degree for its applicants. For this reason, perceived time value is added to the Technology Acceptance Model. Design/methodology/approach. Data are collected from a purposive sample of 147 individuals, who were interested to continue their higher education. Both, online and personal surveys are used to collect data. Achieved data are analysed by structural equation modelling. Findings. The results show that the perceived time value is significantly related to the ease of use and perceived utility, which in turn, show a signifi…