Search results for " Circular"
showing 10 items of 253 documents
Self-Assembly of Supramolecular Polymers of N-Centered Triarylamine Trisamides in the Light of Circular Dichroism: Reaching Consensus between Electro…
2020
The self-assembly of chiral supramolecular polymers is an intricate process that spans a wide range of length scales. Circular dichroism techniques are ideal to study this process as they provide information on the molecular scale but are at the same time also sensitive probes of the long-range interactions that control the growth and morphology of these polymers. As yet, Electronic Circular Dichroism that uses electronic transitions as a probe has by far been the method of choice while Vibrational Circular Dichroism, which uses vibrational transitions to probe structure, is much less employed. Here, we report experimental and theoretical studies of the self-assembly of helical supramolecul…
Occurrence of Fusarium mycotoxins in Italian cereal and cereal products from organic farming.
2013
In the present study, the occurrence of eighteen mycotoxins, nine trichothecenes (deoxynivalenol, 3-acetyl-deoxynivalenol, 15-acetyl-deoxynivalenol, nivalenol, neosolaniol, diacetoxyscirpenol, fusarenon-X, T-2 toxin and HT-2 toxin), three zearalenones (zearalenone, α-zearalenol and β-zearalenol), and six emergent mycotoxins, beauvericin and five enniatins (A, A1, B, B1 and B4), was monitored in different Italian organic cereals and cereal products by using a liquid chromatography coupled to triple quadrupole mass spectrometry method. A total of 93 organic cereal samples (wheat, barley, rye and oat) were collected from Italy. Limits of quantification ranged from 5 to 15 μg/kg. 80% of analyze…
GUI Implementation of VCDtools, A Program to Analyze Computed Vibrational Circular Dichroism Spectra
2020
As computing power increases, vibrational circular dichroism (VCD) calculations on molecules of larger sizes and complexities become possible. At the same time, the spectra resulting from these computations become increasingly more cumbersome to analyze. Here, we describe the GUI implementation into the Amsterdam Density Functional (ADF) software package of VCDtools, a toolbox that provides a user-friendly means to analyze VCD spectra. Key features are the use of the generalized coupled oscillator analysis methods, as well as an easy visualization of the atomic electric and magnetic transition dipole moments which together provide detailed insight in the origin of the VCD intensity. Using s…
High Diversity of the Viral Community from an Antarctic Lake
2009
Viruses are the most abundant biological entities and can control microbial communities, but their identity in terrestrial and freshwater Antarctic ecosystems is unknown. The genetic structure of an Antarctic lake viral community revealed unexpected genetic richness distributed across the highest number of viral families that have been found to date in aquatic viral metagenomes. In contrast to other known aquatic viromes, which are dominated by bacteriophage sequences, this Antarctic virus assemblage had a large proportion of sequences related to eukaryotic viruses, including phycodnaviruses and single-stranded DNA (ssDNA) viruses not previously identified in aquatic environments. We also o…
Mutational analysis of eggplant latent viroid RNA processing in Chlamydomonas reinhardtii chloroplast.
2009
Viroids of the family Avsunviroidae, such as eggplant latent viroid (ELVd), contain hammerhead ribozymes and replicate in the chloroplasts of the host plant through an RNA-based symmetrical rolling-circle mechanism in which oligomeric RNAs of both polarity are processed to monomeric linear RNAs (by cleavage) and to monomeric circular RNAs (by ligation). Using an experimental system consisting of transplastomic lines of the alga Chlamydomonas reinhardtii, a mutational analysis of sequence and structural elements in the ELVd molecule that are involved in transcript processing in vivo in a chloroplastic context was carried out. A collection of six insertion and three deletion ELVd mutants was …
Conceptualizing Core Aspects on Circular Economy in Cities
2021
Currently, there are many different interpretations in the literature of what a circular economy is and how it functions. As cities are still facing challenges to become fully sustainable, the need for a comprehensive analysis of how the circular economy can be implemented in urban areas is increasing. This article aims at outlining circular cities by their key characteristics and to further explore and provide a framework for fostering circularity at the city level. In order to achieve this goal, we performed a systematic review and analyzed key papers published in the field of circular economy to determine how circular economy practices form circular cities. We discovered that cities play…
Turning waste into gold: Sustainable feed made of discards from the food industries promotes gonad development and colouration in the commercial sea …
2021
Abstract Development of sustainable aquaculture practices is a suitable solution to reduce the pressure on overexploited stocks of the Mediterranean sea urchin, Paracentrotus lividus, and to respond to the increasing market demand. To move forward the Blue Growth and following the principles of circular economy, a three-month feeding experiment was conducted to test a sustainable feed based on food processing discards on sea urchins. Two feed formulations differing on the proportions of the two main ingredients (endive outermost leaves and European anchovy discards in a ratio of 60:40 and 80:20 respectively) were prepared and tested on P. lividus gonad yield, development and quality. The re…
NATURALLY AVAILABLE SOLUTIONS FOR BUILDING NEW METABOLIC TERRITORIES
2021
Building new metabolic territories is a proactive way of responding to the challenges and precariousness of the contemporary city. Byintegrating solutions inspired by new scientific advances in urban ecology, cities are able to address some of the environmental threats. Many European cities are implementing alternative nature-based solutions to protect their health and tackle water scarcity, land consumption and climate change, to increase citizens' well-being. Wellbeing and health (Agenda 2030) are the most important analytical parameters for measuring the results and impacts of environmental project actions. With this in mind, the study presents a "nature-action" project hypothesis for wh…
Hepatitis B protein HBx binds the DLEU2 lncRNA to sustain cccDNA and host cancer-related gene transcription.
2019
Objective: The HBV HBx regulatory protein is required for transcription from the covalently closed circular DNA (cccDNA) minichromosome and affects the epigenetic control of both viral and host cellular chromatin. Design: We explored, in relevant cellular models of HBV replication, the functional consequences of HBx interaction with DLEU2, a long non-coding RNA (lncRNA) expressed in the liver and increased in human hepatocellular carcinoma (HCC), in the regulation of host target genes and the HBV cccDNA. Results: We show that HBx binds the promoter region, enhances the transcription and induces the accumulation of DLEU2 in infected hepatocytes. We found that nuclear DLEU2 directly binds HBx…
Multiplet coupling and band structure in L2,3-edge XAS through multi-channel multiple scattering theory.
2009
International audience; Using the recently developed multi-channel multiple scattering (MCMS) method we have calculated the x-ray absorption spectra (XAS) at the L2,3-edge of transition metal compounds. The MCMS method is an ab initio scheme which combines an accurate description of the band structure of the material with a correlated many-electron wave function on the absorber atom. Thereby configuration interaction in the XAS final state, in particular multiplet effects, can be taken into account. In the present implementation, we use an electron-hole wave function and treat the interaction with all other electrons on a mean-field level. The calculated spectra agree well with experiment f…