Search results for "RICH"
showing 10 items of 3360 documents
Two-Stage Origin of K-Enrichment in Ultrapotassic Magmatism Simulated by Melting of Experimentally Metasomatized Mantle
2019
The generation of strongly potassic melts in the mantle requires the presence of phlogopite in the melting assemblage, while isotopic and trace element analyses of ultrapotassic rocks frequently indicate the involvement of subducted crustal lithologies in the source. However, phlogopite-free experiments that focus on melting of sedimentary rocks and subsequent hybridization with mantle rocks at pressures of 1&ndash
Transitions in a stratified Kolmogorov flow
2016
We study the Kolmogorov flow with weak stratification. We consider a stabilizing uniform temperature gradient and examine the transitions leading the flow to chaotic states. By solving the equations numerically we construct the bifurcation diagram describing how the Kolmogorov flow, through a sequence of transitions, passes from its laminar solution toward weakly chaotic states. We consider the case when the Richardson number (measure of the intensity of the temperature gradient) is $$Ri=10^{-5}$$ , and restrict our analysis to the range $$0<Re<30$$ . The effect of the stabilizing temperature is to shift bifurcation points and to reduce the region of existence of stable drifting states. The…
Ulota larrainii (Orthotrichoideae, Orthotrichaceae, Bryophyta) a new species from Chile, with comments on the worldwide diversification of the genus
2015
A new species of Ulota D. Mohr, U. larrainii, is described from the Aysén Region, southern Chile. The characters that discriminate the new moss are the prostrate habit, leaves not crisped, marginal cells of the leaf base differentiated in 1(2) rows, vaginula hairy, exostome of 8 pairs of orange, recurved teeth, endostome of 16 broad and hyaline segments, and large, multicellular spores. The new moss is illustrated and compared with similar taxa. In addition, the presence of multicellular spores in the genus Ulota is summarized and evaluated from an updated list of currently accepted species. Finally, the distribution, species richness and levels of endemism in the different regions where Ul…
Brief an Johann G. Herder.
1799
Ms. 930a, Nr. 17, Bl. 43r-44v Garlieb H. Merkel. Brief an Johann G. Herder. Berlin, d[en] 9ten März 1799 Autora rokraksts / Autograph, vācuval. / Deutsch [4] lpp. / S. Attēlu numuri / Bildnummern: 930a-017-1, 930a-017-2-3, 930a-017-4 Wahrscheinlich handelt es sich bei diesem Dokument um ein Konzeptdes Briefes von Merkel an Herder; es ist also nicht gesichert, ob dieser in Reinschrift verfasst undan den Adressaten abgeschickt wurde. Merkel schreibt sehr persönlich über sich selbst und versucht das Bild eines draufgängerischen Lebemannes zu geben, der seinen Horizont, wenn möglich, lieber durch eigene Erfahrungen als durch Buchlektüre erweitern will. Merkel weiß, dass er diese Sichtweise mit …
Intérêts du phénotypage de la personnalité pour améliorer la lutte biologique : cas d’étude chez l’auxiliaire Trichogramma evanescens
2021
One promising approach to improve the use of biological control agents (BCA) consists in the exploitation of intraspecific variation on traits related to mass-rearing or field performance. Consistent inter-individual variations in behaviour (known as personality) have never been considered in biological control (BC) while they have proved to be heritable and correlated to phenotypic traits possibly related to fitness in rearing or field conditions. The aim of this PhD thesis was (i) to develop an experimental design to measure personality traits in a the egg-parasitoid Trichogramma evanescens, and (ii) to evaluate the feasibility and interest of phenotyping personality traits to set and imp…
Parametric nonlinear singular Dirichlet problems
2019
Abstract We consider a nonlinear parametric Dirichlet problem driven by the p -Laplacian and a reaction which exhibits the competing effects of a singular term and of a resonant perturbation. Using variational methods together with suitable truncation and comparison techniques, we prove a bifurcation-type theorem describing the dependence on the parameter of the set of positive solutions.
Vegetation of rock clefts and ledges in the Pamir Alai Mts, Tajikistan (Middle Asia)
2014
AbstractThe paper presents the results of phytosociological research conducted on the vegetation of rock clefts and ledges in the Pamir-Alai Mountains (Tajikistan, Middle Asia). During the field studies, done in 2010–2012, 101 phytosociological relevés were taken. Plant species were recorded according to the Braun-Blanquet cover-abundance scale. Communities of calcareous rock clefts and ledges with small soil amounts from several ranges (Zeravshan Mts, Hissar Mts, Hazratishokh Mts, Darvaz Mts, Rushan Mts and Vanch Mts), inhabiting mainly the alpine and subnival zone, have been described. A synopsis of the rock communities of the Pamir-Alai is proposed. In the examined vegetation plots 77 va…
Surface Components of Escherichia coli That Mediate Resistance to the Bactericidal Activities of Serum and Phagocytes
1985
Microorganisms that enter the animal body, either actively or passively, encounter a battery of nonspecific and specific chemical and cellular defenses whose role is to inactivate and eliminate foreign materials. Successful pathogens have the ability to avoid, resist, or inactivate these defenses for at least the period necessary for initiation of the disease process.
Mycotoxin Incidence in Some Fish Products: QuEChERS Methodology and Liquid Chromatography Linear Ion Trap Tandem Mass Spectrometry Approach
2019
The inclusion of vegetal raw materials in feed for fish farming has increased the risk of mycotoxin occurrence in feed, as well as in edible tissues from fish fed with contaminated feed, due to the carry-over to muscle portions. Therefore, the objective of this study was to evaluate the occurrence of 15 mycotoxins in processed fish products, which are commonly consumed, such as smoked salmon and trout, different types of sushi, and gula substitutes. A QuEChERS method was employed to perform the mycotoxin extraction from fish samples. For mycotoxin identification and quantitation, the selected technique was the liquid chromatography-tandem mass spectrometry linear ion trap (LC-MS/MS-LIT). Sm…
Die Beziehung zwischen der Guanethidin-Konzentration im Rattenherzen und dem Noradrenalingehalt
1962
Guanethidine was intravenously injected into rats and was subsequently determined in the hearts by extracting the tissue with trichloroacetic acid, purifying the extracts on cation exchange columns and by paper chromatography, and coupling the guanethidine with ninhydrin in alkaline solution before fluorimetric estimation. The concentration in the heart reached a maximum of 9 μg/g within 15 min of injecting 15 mg/kg, and was still 6.2 and 5.7 μg/g after 1 and 3 hours, respectively. Guanethidine caused a decrease of the heart noradrenaline concentration, measured fluorimetrically, by 56% in 3 hours and by 93% in 14 hours. The adrenaline concentration was likewise decreased. A metabolite with…