Beyond Gross-Pitaevskii Mean Field Theory

A large number of effects related to the phenomenon of Bose-Einstein Condensation (BEC) can be understood in terms of lowest order mean field theory, whereby the entire system is assumed to be condensed, with thermal and quantum fluctuations completely ignored. Such a treatment leads to the Gross-Pitaevskii Equation (GPE) used extensively throughout this book. Although this theory works remarkably well for a broad range of experimental parameters, a more complete treatment is required for understanding various experiments, including experiments with solitons and vortices. Such treatments should include the dynamical coupling of the condensate to the thermal cloud, the effect of dimensionality, the role of quantum fluctuations, and should also describe the critical regime, including the process of condensate formation. The aim of this Chapter is to give a brief but insightful overview of various recent theories, which extend beyond the GPE. To keep the discussion brief, only the main notions and conclusions will be presented. This Chapter generalizes the presentation of Chapter 1, by explicitly maintaining fluctuations around the condensate order parameter. While the theoretical arguments outlined here are generic, the emphasis is on approaches suitable for describing single weakly-interacting atomic Bose gases in harmonic traps. Interesting effects arising when condensates are trapped in double-well potentials and optical lattices, as well as the cases of spinor condensates, and atomic-molecular coupling, along with the modified or alternative theories needed to describe them, will not be covered here.Comment: Review Article (19 Pages) - To appear in 'Emergent Nonlinear Phenomena in Bose-Einstein Condensates: Theory and Experiment', Edited by P.G. Kevrekidis, D.J. Frantzeskakis and R. Carretero-Gonzalez (Springer Verlag

The Microbiome of Brazilian Mangrove Sediments as Revealed by Metagenomics

Here we embark in a deep metagenomic survey that revealed the taxonomic and potential metabolic pathways aspects of mangrove sediment microbiology. The extraction of DNA from sediment samples and the direct application of pyrosequencing resulted in approximately 215 Mb of data from four distinct mangrove areas (BrMgv01 to 04) in Brazil. The taxonomic approaches applied revealed the dominance of Deltaproteobacteria and Gammaproteobacteria in the samples. Paired statistical analysis showed higher proportions of specific taxonomic groups in each dataset. The metabolic reconstruction indicated the possible occurrence of processes modulated by the prevailing conditions found in mangrove sediments. In terms of carbon cycling, the sequences indicated the prevalence of genes involved in the metabolism of methane, formaldehyde, and carbon dioxide. With respect to the nitrogen cycle, evidence for sequences associated with dissimilatory reduction of nitrate, nitrogen immobilization, and denitrification was detected. Sequences related to the production of adenylsulfate, sulfite, and H2S were relevant to the sulphur cycle. These data indicate that the microbial core involved in methane, nitrogen, and sulphur metabolism consists mainly of Burkholderiaceae, Planctomycetaceae, Rhodobacteraceae, and Desulfobacteraceae. Comparison of our data to datasets from soil and sea samples resulted in the allotment of the mangrove sediments between those samples. The results of this study add valuable data about the composition of microbial communities in mangroves and also shed light on possible transformations promoted by microbial organisms in mangrove sediments

Generation of flavors and fragrances through biotransformation and de novo synthesis

Flavors and fragrances are the result of the presence of volatile and non-volatile compounds, appreciated mostly by the sense of smell once they usually have pleasant odors. They are used in perfumes and perfumed products, as well as for the flavoring of foods and beverages. In fact the ability of the microorganisms to produce flavors and fragrances has been described for a long time, but the relationship between the flavor formation and the microbial growth was only recently established. After that, efforts have been put in the analysis and optimization of food fermentations that led to the investigation of microorganisms and their capacity to produce flavors and fragrances, either by de novo synthesis or biotransformation. In this review, we aim to resume the recent achievements in the production of the most relevant flavors by bioconversion/biotransformation or de novo synthesis, its market value, prominent strains used, and their production rates/maximum concentrations.We would like to thank the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469 unit, COMPETE 2020 (POCI-01-0145FEDER-006684), and BiotecNorte operation (NORTE-01-0145FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

A phylogeny-driven genomic encyclopaedia of Bacteria and Archaea

Sequencing of bacterial and archaeal genomes has revolutionized our understanding of the many roles played by microorganisms. There are now nearly 1,000 completed bacterial and archaeal genomes available, most of which were chosen for sequencing on the basis of their physiology. As a result, the perspective provided by the currently available genomes is limited by a highly biased phylogenetic distribution. To explore the value added by choosing microbial genomes for sequencing on the basis of their evolutionary relationships, we have sequenced and analysed the genomes of 56 culturable species of Bacteria and Archaea selected to maximize phylogenetic coverage. Analysis of these genomes demonstrated pronounced benefits (compared to an equivalent set of genomes randomly selected from the existing database) in diverse areas including the reconstruction of phylogenetic history, the discovery of new protein families and biological properties, and the prediction of functions for known genes from other organisms. Our results strongly support the need for systematic phylogenomic efforts to compile a phylogeny-driven Genomic Encyclopedia of Bacteria and Archaea in order to derive maximum knowledge from existing microbial genome data as well as from genome sequences to come. © 2009 Macmillan Publishers Limited. All rights reserved

Antipsychotic use and the risk of hip/femur fracture: a population-based case-control study

Summary: this case–control study showed that current use of conventional antipsychotics, but not atypical antipsychotics, seems to be associated with an increased risk of a hip/femur fracture, possibly related to the pharmacological properties of conventional antipsychotics. Furthermore, no evidence for a dose effect was found.Introduction: the aim of this study was to assess the risk of hip/femur fracture associated with antipsychotic use, with particular reference to any difference in risk with conventional versus atypical antipsychotics, dose, and pharmacological properties.Methods: a case–control study was conducted using data from the PHARMO Record Linkage System among individuals aged 18 years and older between 1991 and 2002. Cases had a record of a hip or femur fracture, while controls had no evidence of ever having sustained any fracture.Results: most cases were elderly (77.6% aged ?70 years). We found an increased risk for hip/femur fracture associated with the use of antipsychotic drugs. The risk for current users (ORadj 1.68 [1.43, 1.99]) was significantly greater than with past use (ORadj 1.33 [1.14, 1.56]; p?=?0.036). Current use of conventional antipsychotics (ORadj 1.76 [1.48, 2.08]) but not atypical antipsychotics (ORadj 0.83 [0.42, 1.65]) was associated with an increased risk. We did not find evidence for a dose effect.Conclusion: the use of conventional, but not atypical antipsychotics, seems to be associated with an increased risk of hip/femur fracture, possibly related to the pharmacological properties of conventional antipsychotics. However, the numbers of atypical antipsychotic users were small, and therefore this observation needs further attention in other study population

Aneurismas dissecantes intracranianos da circulação posterior relato de três casos e revisão da literatura

As dissecções dos vasos cerebrais é causa rara de acidente vascular cerebral (quarta causa). Geralmente são de aparecimento espontâneo ou após trauma simples. É mais comprometido o sistema carotídeo e a evolução costuma ser benigna. As dissecções do sistema vértebro-basilar são menos comuns e a dissecção primária da artéria basilar é rara. As dissecções da circulação posterior têm sido diagnosticadas em proporção crescente, porém, seus mecanismos de lesão, o quadro clínico, os critérios de diagnóstico e o tratamento constituem problema da prática neurológica e a taxa de morbidade e mortalidade ainda é alta. Os autores abordam estes problemas e sugerem medidas que possam ser úteis no manuseio dessa patologia. Descrevem-se três casos de dissecção, dois da artéria vertebral e um da artéria basilar. É feito também levantamento de 80 casos já publicados, comparando-os aos três casos descritos