Search results for "Roca"

Data from: Moving in the Anthropocene: global reductions in terrestrial mammalian movements

2019

Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects no…

Chlorinated hydrocarbons and mercury in aquatic vascular plants of lake Päijänne, Finland

1978

Periodic Polynomial Splines

2018

In this chapter, the spaces of periodic polynomial splines and the Spline Harmonic Analysis (SHA) in these spaces are briefly outlined. The stuff of this chapter is used for the design of periodic discrete-time splines and discrete-time-spline-based wavelets and wavelet packets. For a detailed description of the subject we refer to (Averbuch, Neittaanmaki and Zheludev, Spline and Spline Wavelet Methods with Applications to Signal and Image Processing, Springer, Berlin, 2014) [1]. Periodic polynomial splines provide an example of mixed discrete-continuous circular convolution.

Isolation and characterization of hydrocarbonoclastic bacteria from Algerian coast

2017

Backgrounds The contamination of marine environments by hydrocarbons represents a global concern with consequences on ecosystems and human health. The removal of HC by physical and/or chemical methods is expensive and disrespectful of the environment. The use of HC degrading bacteria is a good alternative for environmental remediation (bioremediation). Objectives The Algerian coastline is exposed to several types of pollutions, including hydrocarbons. The aim was to explore the bioremediation potential of its contaminated harbors for the first time. Methods To identify the hydrocarbon degrading bacteria seawater samples were collected in Sidi fredj harbor (Algeria) and used to enrichment cu…

Monolayers of dipalmitoylphosphatidylcholine at the oil-water interface

1995

Abstract Monolayers of dipalmitoylphosphatidylcholine at the interfaces waterbicylohexyl, waterdodecane and waterhexadecane were studied by fluorescence microscopy and thermodynamic measurements. The experiments show that the oil also partitions in the liquid condensed (LC) monolayer phase with concentration depending on the type of oil and the lateral pressure. In contrast to monolayers of dipalmitoylphosphatidylethanolamine the larger molecular area per head group enables oil partitioning in the LC phase even if there is a mismatch between the aliphatic tails of liquid and alkane.

Group contributions to the infinite dilution partial molar volumes of alkanes, alcohols, and glycols in polar organic solvents

1997

Densities of binary mixtures of polar organic solvents with alcohols were measured at 25‡C. The solvents studied were N,N-dimethylformamide, dimethylsulfoxide, and formamide while alcohols were butanol, pentanol, hexanol, and 1,4-butanediol. Density measurements of hydrocarbons (from pentane to dodecane and some heptane isomers) + N,N-dimethylformamide were also performed. From these data the apparent molar volumes of alcohols and hydrocarbons as functions of concentration were calculated. The standard partial molar volumes were obtained by extrapolation to infinite dilution and are discussed in terms of group contributions.

Deep oxidation of volatile organic compounds using ordered cobalt oxides prepared by a nanocasting route

2010

Ordered Co3O4 with high surface area (until 173 m2/g) has been successfully obtained through a nanocasting route using mesoporous KIT-6 silica as a hard template and tested in the deep oxidation of a series of representative volatile organic compounds (VOCs): propane as a model of short chain alkane and toluene as a model of monoaromatic hydrocarbon. It has been demonstrated that the catalytic activity for VOC deep oxidation is very elevated and its catalytic stability at moderate temperatures very good. However, the role of the ordered structure in the catalytic performance does not seem to be beneficial. The enhanced catalytic activity has been explained in terms of both the high surface …

Novel Approach for Asymmetric Synthesis of Fluorinated β-Amino Sulfones and Allylic Amines

2003

[reaction: see text] Enantiomerically pure gamma-fluoroalkyl beta-amino sulfones are readily synthesized in three steps starting from fluorinated imidoyl chlorides and arylmethyl sulfones. A complementary two-step sequence starting from chiral fluorinated beta-amino sulfoxides has also been developed. To illustrate the application of this procedure, a new method for the synthesis of alpha-fluoroalkyl allylic amines in optically pure form involving a Julia methylenation-desulfonylation reaction is presented.

Effects of amsacrine (m-AMSA), a new aminoacridine antitumor drug, on the rabbit heart.

1983

There is emerging clinical evidence that amsacrine (m-AMSA) administration may be associated with cardiotoxic effects such as severe, even fatal, ventricular arrhythmias and impairment of the inotropic performance of the heart. Information on the cardiac effects of m-AMSA in animals is scanty. Studies on mice, dogs, and monkeys have not evidenced the cardiotoxicity of the compound. The data presented in this paper show that m-AMSA causes acute ECG alterations in normal rabbits and a dose-related negative inotropic effect on the isolated rabbit heart, suggesting that this species may be a useful model for the study of the cardiac actions of this antiblastic.

Highly Sensitive Detection of Naphthalene in Solvent Vapor Using a Functionalized PBG Refractive Index Sensor

2012

We report an optical refractive index sensor system based on a planar Bragg grating which is functionalized by substituted γ-cyclodextrin to determine low concentrations of naphthalene in solvent vapor. The sensor system exhibits a quasi-instantaneous shift of the Bragg wavelength and is therefore capable for online detection. The overall shift of the Bragg wavelength reveals a linear relationship to the analyte concentration with a gradient of 12.5 ± 1.5 pm/ppm. Due to the spectral resolution and repeatability of the interrogation system, this corresponds to acquisition steps of 80 ppb. Taking into account the experimentally detected signal noise a minimum detection limit of 0.48 ± 0.05 pp…