Open questions in utility theory

Throughout this paper, our main idea is to explore different classical questions arising in Utility Theory, with a particular attention to those that lean on numerical representations of preference orderings. We intend to present a survey of open questions in that discipline, also showing the state-of-art of the corresponding literature.This work is partially supported by the research projects ECO2015-65031-R, MTM2015-63608-P (MINECO/ AEI-FEDER, UE), and TIN2016-77356-P (MINECO/ AEI-FEDER, UE)

Finding the Needles in the Metagenome Haystack

In the collective genomes (the metagenome) of the microorganisms inhabiting the Earth’s diverse environments is written the history of life on this planet. New molecular tools developed and used for the past 15 years by microbial ecologists are facilitating the extraction, cloning, screening, and sequencing of these genomes. This approach allows microbial ecologists to access and study the full range of microbial diversity, regardless of our ability to culture organisms, and provides an unprecedented access to the breadth of natural products that these genomes encode. However, there is no way that the mere collection of sequences, no matter how expansive, can provide full coverage of the complex world of microbial metagenomes within the foreseeable future. Furthermore, although it is possible to fish out highly informative and useful genes from the sea of gene diversity in the environment, this can be a highly tedious and inefficient procedure. Microbial ecologists must be clever in their pursuit of ecologically relevant, valuable, and niche-defining genomic information within the vast haystack of microbial diversity. In this report, we seek to describe advances and prospects that will help microbial ecologists glean more knowledge from investigations into metagenomes. These include technological advances in sequencing and cloning methodologies, as well as improvements in annotation and comparative sequence analysis. More significant, however, will be ways to focus in on various subsets of the metagenome that may be of particular relevance, either by limiting the target community under study or improving the focus or speed of screening procedures. Lastly, given the cost and infrastructure necessary for large metagenome projects, and the almost inexhaustible amount of data they can produce, trends toward broader use of metagenome data across the research community coupled with the needed investment in bioinformatics infrastructure devoted to metagenomics will no doubt further increase the value of metagenomic studies in various environments

Defining the importance of landscape metrics for large branchiopod biodiversity and conservation: the case of the Iberian Peninsula and Balearic Islands

The deficiency in the distributional data of invertebrate taxa is one of the major impediments acting on the bias towards the low awareness of its conservation status. The present study sets a basic framework to understand the large branchiopods distribution in the Iberian Peninsula and Balearic Islands. Since the extensive surveys performed in the late 1980s, no more studies existed updating the information for the whole studied area. The present study fills the gap, gathering together all available information on large branchiopods distribution since 1995, and analysing the effect of human population density and several landscape characteristics on their distribution, taking into consideration different spatial scales (100 m, 1 km and 10 km). In overall, 28 large branchiopod taxa (17 anostracans, 7 notostracans and 4 spinicaudatans) are known to occur in the area. Approximately 30% of the sites hosted multiple species, with a maximum of 6 species. Significant positive co-occurring species pairs were found clustered together, forming 4 different associations of large branchiopod species. In general, species clustered in the same group showed similar responses to analysed landscape characteristics, usually showing a better fit at higher spatial scales.Brazilian Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq [401045/2014-5]Spanish Ministry of Education, Culture and Sport [FPU014/06783]info:eu-repo/semantics/publishedVersio

Propeller-like Conformation of Diphenylacetic Acid

Abstract Crystal structure of diphenylacetic acid has been solved by X-ray diffraction. The crystals are monoclinic, space group P21/c, with a = 12.254(4) Å, b = 7.2260(8) Å, c = 17.521(4) Å, ß = 133.38(1)°, Mr = 212.24, V = 1127.6(5) Å3, Z = 4 and R = 0.045. A strong hydrogen bond links the molecules in dimers. The dimers are connected by weaker C–H···p and p···p interactions. A calculation was performed for the isolated molecule and for the dimer within the Hartree-Fock (HF) level with a 6-311G(d) basis set. In both calculations, the minimum of the energy is achieved with the phenyl rings assuming a more symmetric arrangement around the central carboxylic plane than is experimentally observed. Graphical Abstract In diphenylacetic acid the molecules are coupled in dimers by a strong hydrogen bonds. Weaker intermolecular interactions involving the aromatic ring p systems join the dimers together

X-ray Diffraction and DFT Studies of 2-Methoxy-5-phenylaniline

Abstract 2-Methoxy-5-phenylaniline, a promissor monomer for PANI studies, has been characterized by single-crystal X-ray diffraction at two temperatures: orthorhombic, space group P212121, Z = 12 with a = 5.9900(2) Å, b = 20.4873(6) Å, c = 26.3727(8) Å and R = 0.0868 for 293(2) K and a = 5.8337(9) Å, b = 20.4428(31) Å, c = 26.0773(40) Å and R = 0.0669 for 120(2) K. There are three independent molecules in the unit cell. One of them is approximately planar, the other two have the phenyl rings rotated. At room temperature the two latter molecules are joined in dimers through H-bonds and at low temperature the same molecules are joined in columns that run along the a-axis. Index Abstract X-ray Diffraction and DFT Studies of 2-Methoxy-5-phenylaniline Ana T. Marques, Joana A. Silva, Manuela Ramos Silva, Ana Matos Beja, Licinia L. G. Justino, Abilio J. F. N. Sobral 2-Methoxy-5-phenylaniline, a promissor monomer for PANI studies, has been characterized by single-crystal X-ray diffraction at 293(2) K and 120(2) K. The three independent molecules in the unit cell show different conformations and establish distinct intermolecular H-bonds