Search results for " composition"

The essential oil composition of the endemic plant species Centaurea vandasii and chemotaxonomy of section Phalolepis (Asteraceae)

2021

In the present study, the chemical composition of the essential oil from aerial parts of the endemic plant species, Centaurea vandasii Velen (sect. Phalolepis, Asteraceae), collected in its locus classicus in Rhodope Mts, Bulgaria, was evaluated by GC-MS. The main components of the oil were hexadecanoic acid (18.3%), tetradecanoic acid (13.8%), caryophyllene oxide (12.1%) and germacrene D (8.4%). Furthermore, a complete literature review on the composition of the essential oils of all the other taxa of Centaurea, belonging to section Phalolepis, studied so far, was performed. HCA (Hierarchical Cluster Analysis) and PCA (Principal Component Analyses) were used in order to demonstrate chemota…

Volatile constituents of Stachys palaestina L. (Palestine woundwort) growing in Lebanon

2014

The hydrodistillation of the aerial parts of Stachys palaestina L. collected in Lebanon in the Kadisha Valley, yielded 0.1% (w/w) of essential oil. GC and GC-MS analyses enabled the identification of 87 compounds representing 90.8% of the total oil. Hexadecanoic acid (10%), hexahydrofarnesyl acetone (6.9%), eugenol (4.3%) and (E)-caryophyllene (4.3%) were the main components. On the whole, the oil was constituted mainly of sesquiterpenes (37.7%), among which sesquiterpene hydrocarbons (20.7%) slightly prevailed over oxygenated sesquiterpenes (17.0%). This is the first report on the chemical composition of S. palaestina essential oil.

Characterization of foxing stains in early twentieth century photographic and paper materials

2016

The subject of this present work is a group of nine historical pictures shot in Palermo by the Sicilian photographer E. Interguglielmi in 1912. They are nine matte-collodion prints mounted on the original cardboard supports and all of them show foxing stains affecting the paper surface. In order to characterise the chemical composition of the supports and investigate foxing spots, non-destructive and micro-destructive analysis were carried out. X-rays fluorescence (XRF) analysis was used to characterise the elemental composition of all the mounting boards, allowing a comparison between the foxing spots and non-affected areas. Laser-Induced Breakdown Spectroscopy was used to investigate the …

Particle Distribution, Composition, and Processing during Cloud, Fog, and Rain Cycles

2007

Impact of processing on mineral bioaccessibility/bioavailability

2019

Abstract A review is made of the influence of processing on the bioaccessibility/bioavailability of macrominerals (Ca, P, Mg and K) and microminerals (Fe, Cu, Zn and Se). In vegetable foods, household processes (dehulling, soaking, germination and fermentation) alone or with thermal processing increase mineral bioaccessibility, mainly referred to Fe, Cu, Zn, Se and Ca. The application of thermal processing to vegetable foods has different effects upon mineral bioaccessibility, with an overall increase in Ca and Fe and a decrease in Se. In turn, there is a general positive impact upon mineral bioaccessibility in animal foods when conventional thermal processing is used with shorter times and…

Ultrastructural localization of Ca2(+)-binding sites in the middle ear mucosa of the rat.

1990

Cations were precipitated with potassium-pyroantimonate in the middle ear mucosa of the rat and the distribution of the formed precipitates was studied by electron microscopy. The precipitate density in various cells of the different epithelia of the middle ear mucosa was determined on electron micrographs by counting the number of precipitates per unit area. Electron spectroscopic imaging was also performed to obtain information about the spatial distribution of the precipitates and their elemental composition.

Anatomical Network Comparison of Human Upper and Lower, Newborn and Adult, and Normal and Abnormal Limbs, with Notes on Development, Pathology and Li…

2015

How do the various anatomical parts (modules) of the animal body evolve into very different integrated forms (integration) yet still function properly without decreasing the individual’s survival? This long-standing question remains unanswered for multiple reasons, including lack of consensus about conceptual definitions and approaches, as well as a reasonable bias toward the study of hard tissues over soft tissues. A major difficulty concerns the non-trivial technical hurdles of addressing this problem, specifically the lack of quantitative tools to quantify and compare variation across multiple disparate anatomical parts and tissue types. In this paper we apply for the first time a powerf…

Half-width plots, a simple tool to predict peak shape, reveal column kinetics and characterise chromatographic columns in liquid chromatography: Stat…

2013

Peak profiles in chromatography are characterised by their height, position, width and asymmetry; the two latter depend on the values of the left and right peak half-widths. Simple correlations have been found between the peak half-widths and the retention times. The representation of such correlations has been called half-width plots. For isocratic elution, the plots are parabolic, although often, the parabolas can be approximated to straight-lines. The plots can be obtained with the half-widths/retention time data for a set of solutes experiencing the same kinetics, eluted with a mobile phase at fixed or varying composition. When the analysed solutes experience different resistance to mas…

Nutritional assessment in preterm infants with special reference to body composition

2001

In recent years, improvements in care have significantly improved survival in preterm and, particularily, the very low birth weight infant (VLBW). While immediate survival can be directly related to pulmonary maturity, several studies stress the importance of timely and adequate nutrition in these high-risk infants on a short- and long-term [1]. Yet, nutritional support remains a very controversial issue in these high-risk infants. Early provision of adequate intakes may be limited by clinical instability and immaturity. At the same time, nutritional requirements and methods of nutritional assessment are not well defined. The aim of this paper is to outline some of the methods used during n…

Mumijo traditional medicine: fossil deposits from Antarctica (chemical composition and beneficial bioactivity)

2008

Mumijo is a widely used traditional medicine, especially in Russia, Altai Mountains, Mongolia, Iran Kasachstan and in Kirgistan. Mumijo preparations have been successfully used for the prevention and treatment of infectious diseases; they display immune-stimulating and antiallergic activity as well. In the present study, we investigate the chemical composition and the biomedical potential of a Mumijo(-related) product collected from the Antarctica. The yellow material originates from the snow petrels,Pagodroma nivea. Extensive purification and chemical analysis revealed that the fossil samples are a mixture of glycerol derivatives.In vitroexperiments showed that the Mumijo extract caused in…