Search results for "lcsh:Science"
showing 10 items of 2187 documents
Enhancing Metastability by Dissipation and Driving in an Asymmetric Bistable Quantum System.
2018
The stabilizing effect of quantum fluctuations on the escape process and the relaxation dynamics from a quantum metastable state are investigated. Specifically, the quantum dynamics of a multilevel bistable system coupled to a bosonic Ohmic thermal bath in strong dissipation regime is analyzed. The study is performed by a non-perturbative method based on the real-time path integral approach of the Feynman-Vernon influence functional. We consider a strongly asymmetric double well potential with and without a monochromatic external driving, and with an out-of-equilibrium initial condition. In the absence of driving we observe a nonmonotonic behavior of the escape time from the metastable regi…
Enterobacter cloacae administration induces hepatic damage and subcutaneous fat accumulation in high-fat diet fed mice.
2018
Accumulating evidence indicates that gut microbiota plays a significant role in obesity, insulin resistance and associated liver disorders. Family Enterobacteriaceae and especially Enterobacter cloacae strain B29 have been previously linked to obesity and hepatic damage. The underlying mechanisms, however, remain unclear. Therefore, we comprehensively examined the effects of E. cloacae subsp. cloacae (ATCC® 13047™) administration on host metabolism of mice fed with high-fat diet (HFD). C57BL/6N mice were randomly divided into HFD control, chow control, and E. cloacae treatment groups. The E. cloacae treatment group received live bacterial cells in PBS intragastrically twice a week, every ot…
Necrobia rufipes (De geer) infestation in pet food packaging and setup of a monitoring trap
2020
Simple Summary Necrobia rufipes (Coleoptera: Cleridae) is an emerging pest of pet food stores. Information on infestation modalities for this pest is absent and specific monitoring tools are missing. In this paper, the adults’ and larvae’s ability to enter into pet food packaging was evaluated. Furthermore, to set up of a monitoring trap behavioral bioassays were carried out: testing two adhesive surfaces, one generally used in mouse glue trap and the other used in cockroach trap, to evaluate their ability in avoiding insects’ escape; screening different molecules, as candidate food attractants: methyl cyclopentenolone, squalene and stearic acid. The results evidenced that N. rufipes enter …
Polysubstituted ferrocenes as tunable redox mediators
2018
A series of four ferrocenyl ester compounds, 1-methoxycarbonyl- (1), 1,1’-bis(methoxycarbonyl)- (2), 1,1’,3-tris(methoxycarbonyl)- (3) and 1,1’,3,3’-tetrakis(methoxycarbonyl)ferrocene (4), has been studied with respect to their potential use as redox mediators. The impact of the number and position of ester groups present in 1–4 on the electrochemical potential E1/2 is correlated with the sum of Hammett constants. The 1/1+–4/4+ redox couples are chemically stable under the conditions of electrolysis as demonstrated by IR and UV–vis spectroelectrochemical methods. The energies of the C=O stretching vibrations of the ester moieties and the energies of the UV–vis absorptions of 1–4 and 1+–4+ c…
Proposing a Novel Predictive Technique for Gully Erosion Susceptibility Mapping in Arid and Semi-arid Regions (Iran)
2019
© 2019 by the authors. Gully erosion is considered to be one of the main causes of land degradation in arid and semi-arid territories around the world. In this research, gully erosion susceptibility mapping was carried out in Semnan province (Iran) as a case study in which we tested the efficiency of the index of entropy (IoE), the Vlse Kriterijumska Optimizacija I Kompromisno Resenje (VIKOR) method, and their combination. Remote sensing and geographic information system (GIS) were used to reduce the time and costs needed for rapid assessment of gully erosion. Firstly, a gully erosion inventory map (GEIM) with 206 gully locations was obtained from various sources and randomly divided into t…
School Staff-centered School Development by Communicative Action: Working Methods for Creating Collective Responsibility - From the Idea to Action
2020
School development is often seen as a concerted (re-)action to educational policies, curriculum development, and change in education laws or regulations, and sometimes, as stakeholders’ reactions to low school performance. Generally, school development incorporates organizational, managerial, and educational activities and measures. This is done to adapt to the new situation to achieve the desired changes and goals initiated by a given curriculum reform. In contrast, this paper focuses on school staff–driven development: It describes how teachers together with paraprofessionals contribute to school-development. Using collective responsibility creating working methods of communication, the e…
Competencia Científica y Resolución de Problemas de Física
2020
Resumen Impulsar y desarrollar la competencia científica entre los estudiantes que cursan materias como la Física, es un objetivo contemplado actualmente de forma explícita en la mayoría de los currículos escolares y es compartido por muchos expertos en Didáctica de las Ciencias Experimentales. Sin embargo, cuando se trata este tema con el profesorado de ciencias, suele hacerse ignorando los contenidos concretos de la materia a enseñar, con lo cual, los profesores difícilmente pueden trasladar a sus clases aquello que les ha sido expuesto en términos demasiado generales o abstractos. En nuestra opinión, si realmente se quiere impulsar y desarrollar la competencia científica, ello ha de hace…
SCOPE-Based Emulators for Fast Generation of Synthetic Canopy Reflectance and Sun-Induced Fluorescence Spectra
2017
Progress in advanced radiative transfer models (RTMs) led to an improved understanding of reflectance (R) and sun-induced chlorophyll fluorescence (SIF) emission throughout the leaf and canopy. Among advanced canopy RTMs that have been recently modified to deliver SIF spectral outputs are the energy balance model SCOPE and the 3D models DART and FLIGHT. The downside of these RTMs is that they are computationally expensive, which makes them impractical in routine processing, such as scene generation and retrieval applications. To bypass their computational burden, a computationally effective technique has been proposed by only using a limited number of model runs, called emulation. The idea …
Efficient regio- and stereoselective access to novel fluorinated ?-aminocyclohexanecarboxylates
2013
A regio- and stereoselective method has been developed for the synthesis of novel fluorinated 2-aminocyclohexanecarboxylic acid derivatives with the fluorine attached to position 4 of the ring. The synthesis starts from either cis- or trans-β-aminocyclohex-4-enecarboxylic acids and involves regio- and stereoselective transformation of the ring C–C double bond through iodooxazine formation and hydroxylation, followed by hydroxy–fluorine or oxo–fluorine exchange.
A route to simple nonionic surfactants
2016
AbstractA method for the synthesis of nonionic surfactants – N-alkyl-O-(2-hydroxyethyl) carbamates is proposed by acylation of fatty amines with ethylene carbonate without any solvent or catalyst. The surface tension of the prepared surfactants was measured, toxicity and biodegradability were determined for the surfactant with n-dodecyl as a hydrophobic group and N-monosubstituted amide and hydroxyl groups for their hydrophilic part.