On the astronomical origin of the Hallstatt oscillation found in radiocarbon and climate records throughout the Holocene

An oscillation with a period of about 2100-2500 years, the Hallstatt cycle, is found in cosmogenic radioisotopes (C-14 and Be-10) and in paleoclimate records throughout the Holocene. Herein we demonstrate the astronomical origin of this cycle. Namely, this oscillation is coherent to the major stable resonance involving the four Jovian planets - Jupiter, Saturn, Uranus and Neptune - whose period is p=2318 yr. The Hallstatt cycle could derive from the rhythmic variation of the circularity of the solar system disk assuming that this dynamics could eventually modulate the solar wind and, consequently, the incoming cosmic ray flux and/or the interplanetary/cosmic dust concentration around the Earth-Moon system. The orbit of the planetary mass center (PMC) relative to the Sun is used as a proxy. We analyzed how the instantaneous eccentricity vector of this virtual orbit varies from 13,000 B. C. to 17,000 A. D.. We found that it undergoes kind of pulsations as it clearly presents rhythmic contraction and expansion patterns with a 2318 yr period together with a number of already known faster oscillations associated to the planetary orbital stable resonances. We found that a fast expansion of the Sun-PMC orbit followed by a slow contraction appears to prevent cosmic rays to enter within the system inner region while a slow expansion followed by a fast contraction favors it. Similarly, the same dynamics could modulate the amount of interplanetary/cosmic dust falling on Earth. These would then cause both the radionucleotide production and climate change by means of a cloud/albedo modulation. Other stable orbital resonance frequencies (e.g. at periods of 20 yr, 45 yr, 60 yr, 85 yr, 159-171-185 yr, etc.) are found in radionucleotide, solar, aurora and climate records, as determined in the scientific literature. Thus, the result supports a planetary theory of solar and/or climate variation.Comment: 36 pages, 14 figures, 1 tabl

Synthesis And Characterization Of Polyynes End-Capped By Biphenyl Groups ({\Alpha},{\Omega}-Biphenylpolyynes)

Stable polyyne chains terminated with biphenyl end groups (a,u-biphenylpolyynes) were synthesized in a single step through a simple procedure by using the Cadiot-Chodkiewicz reaction conditions. The a,ubiphenylpolyynes were separated through HPLC analysis and identified by means of their electronic absorption spectra. The a,u-biphenylpolyynes were studied by FT-IR and Raman spectroscopy and the spectral interpretation was supported with DFT calculations. A peculiarly low reactivity of a,u-biphenylpolyynes with ozone was observed.Comment: The research leading to these results has received funding from the European Research Council Consolidator Grant EspLORE (ERC-2016-CoG Grant No.724610

Synthesis, Characterization, and Modeling of Naphthyl-Terminated sp Carbon Chains: Dinaphthylpolyynes

We report a combined study on the synthesis, spectroscopic characterization and theoretical modelling of a series of {\alpha},{\omega}-dinaphthylpolyynes. We synthesized this family of naphtyl-terminated sp carbon chains by reacting diiodoacetylene and 1-ethynylnaphthalene under the Cadiot-Chodkiewicz reaction conditions. By means of liquid chromatography (HPLC), we separated the products and recorded their electronic absorption spectra, which enabled us to identify the complete series of dinaphthylpolyynes Ar-C2n-Ar (with Ar = naphthyl group and n = number of acetilenic units) with n ranging from 2 to 6. The longest wavelength transition (LWT) in the electronic spectra of the dinaphthylpolyynes red shifts linearly with n away from the LWT of the bare termination. This result is also supported by DFT-LDA simulations. Finally, we probed the stability of the dinaphthylpolyynes in a solid-state precipitate by Fourier-transform infrared spectroscopy and by differential scanning calorimetry (DSC).Comment: This document is the unedited Author's version of a Submitted Work that was subsequently accepted for publication in [J. Phys. Chem. B], copyright \c{opyright} American Chemical Society after peer review. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021%2Fjp104863

Genetic analysis of non-recessive factors of resistance to diazinon in the SKA strain of the housefly (Musca domestica L)

RESP-560

Landscape as Heritage: Negotiating European Cultural Identity

environmental policy; identity; European identity

Vibrational characterization of dinaphthylpolyynes: A model system for the study of end-capped sp carbon chains

We perform a systematic investigation of the resonance and vibrational properties of naphthyl-terminated sp carbon chains (dinaphthylpolyynes) by combined multi-wavelength resonant Raman (MWRR) spectroscopy, ultraviolet-visible spectroscopy, and Fourier-transform infrared (FT-IR) spectroscopy, plus ab initio density functional theory (DFT) calculations. We show that the MWWR and FT-IR spectroscopies are particularly suited to identify chains of different lengths and different terminations, respectively. By DFT calculations, we further extend those findings to sp carbon chains end-capped by other organic structures. The present analysis shows that combined MWRR and FT-IR provide a powerful tool to draw a complete picture of chemically stabilized sp carbon chains.Comment: The following article has been accepted by Journal of Chemical Physics. After it is published, it will be found at http://jcp.aip.org

Compreendendo a complexidade socioespacial contemporânea: o território como categoria de diálogo interdisciplinar

O livro constrói um diálogo entre pesquisadores brasileiros e franceses, de diferentes campos do conhecimento, sobre dois temas que passaram a ocupar os espaços do debate acadêmico e das ações públicas, nas duas últimas décadas: a questão do desenvolvimento e a questão territorial. Duas questões foram colocadas para os pesquisadores: qual o significado do conceito de território a partir de seu campo de estudo e quais contribuições podem aportar para a compreensão dos processos de desenvolvimento. Além de um rico debate no sentido epistemológico, a partir dos diversos campos de análise o livro aponta também algumas indagações: como trabalhar a relação entre espaço e território, como caraceterizar fronteiras territoriais em um mundo em que, elas marcam profundamente tanto a união/ intercâmbio quanto a ruptura/interdição? E várias outras quetões que compoem a agenda de debate da economia, geografia, ciencias políticas, sociologia e da administração

Potentials and challenges between epistemological blindness and problematization in the research with the school

Este artigo objetiva analisar como o processo de pesquisar com a escola pode potencializar olhares epistemológicos plurais quando construídos no coletivo de professoras-pesquisadoras que atuam na escola e professoras-pesquisadoras atuantes na universidade. Para tanto, foi realizada uma aproximação das noções de cegueira epistemológica e de problematização. Como caminho investigativo, seguiram-se os atinentes à investigação de inspiração etnográfica realizada pelo Grupo de Pesquisa. Os excertos aqui selecionados, de 2017, são oriundos de reuniões com professoras atuantes em uma escola pública do sul do país. Este exercício analítico possibilitou concluir que a aproximação das noções se tornou potente e desafiante para o processo de pesquisar com a escola. Potente ao assumir a pesquisa como um gesto investigativo que pluraliza verdades, e não a aplicação de metodologias que resultam em resposta única. Igualmente potente ao afastar-se do agir cotidiano para pensar práticas de avaliação e (in)disciplina, como ilustrado neste texto, para pensá-las não apenas como temas da escola, mas como problemas, decisões tomadas como efeito das relações de poder imbricadas com determinado caráter político-epistemológico operando na escola. Dar-se conta da parcialidade de nossa visão e problematizar fazeres e saberes cotidianos no processo de pesquisar com é pensar a própria ciência ao discutirem-se, por exemplo, práticas de avaliação e a (in)disciplina na escola. Desafiante ao perceber que pesquisar com, considerando as cegueiras epistemológicas, é compreender que não serão superadas, mas que, ao visibilizá-las, o olhar do pesquisador se torna vigilante às armadilhas das generalizações e verdades absolutas historicamente assépticas.This article attempts to analyze how the process of researching with the school can potentiate plural epistemological views when constructed in the collective of school teachers and teachers attached to the university. In order to do so, the notions of epistemological blindness and problematization were approached. As research path, this study follows the perspectives of an research inspired by ethnography. The records selected here, from 2017, come from meetings with public school teachers of south of the country. This analytical exercise made it possible to conclude that the approach of the notions became potent and challenging for the process of researching with the school. Potent, by taking the research as an investigative gesture that pluralizes truths and does not apply methodologies that result in unique response. Equally potent, by stepping aside from everyday action to think of practices of evaluation and (in)discipline, as illustrated in this text, not only as school themes, but as problems, decisions imbricated in power relations with a certain political-epistemological character operating in school. To realize the partiality of our vision and to problematize everyday activities and knowledge in the process of researching is to think about science itself when discussing, for example, evaluation practices and (in)discipline in school. Challenging, when realizing that our epistemological blindness in the process of researching with will not be overcome, but by making them visible the researcher's becomes vigilant to the possible generalizations traps and to the aseptic absolute truths historically constructed

Prospective study of a group of pre-university students evaluating anxiety and depression relationships with temporomandibular disorders

Objectives: The aim of this prospective longitudinal study was to evaluate the relationships between anxiety, depression, and temporomandibular disorders (TMD) in a sample of pre-university students submitted to a stressful event. Study design: 153 students from a pre-university course (82 females and 71 males between 16 and 31 years old) were given a survey about TMD symptoms and a survey about anxiety and depression scale at the beginning and the end of the preparatory course (August 2009-T1, and November 2009-T2). Results: Results were analyzed using a chi-square test and Odds Ratio (OR), significance level of á = 0.05. Statistical significance were found to depression rates in students with TMD (16% on T1 and 26% on T2, p = 0.001) as well as in general sample (12% on T1 and 22% on T2, p = 0.009), anxiety and TMD symptoms presented constant rates in both periods. Increased risk of having TMD were found in participants with anxiety (OR 2.6 in T2 and 5.6 in T1) and depression (2.0 in T2 and 3.3 in T1), but only anxiety reach statistical significance in both periods. Conclusions: TMD symptoms were a fluctuating variable that exchange between some individuals of this study. Independently of the TMD, depression rates significant increased in the evaluated period. Finally, anxiety was the psychological symptom related to the increased risk of having TMD

Semiconductor-to-Metal Transition in Carbon-Atom Wires Driven by sp2 Conjugated End Groups

Bis(biphenyl)-capped polyynes are investigated to unveil the modulation of the electronic and optical properties of sp-hybridized carbon-atom wires (CAWs) capped with π-conjugated sp2 end groups. Raman and surface enhanced Raman spectroscopy experiments and density functional theory (DFT) calculations reveal structural changes from polyyne-like with alternating single–triple bonds toward cumulene-like with more equalized bonds as a consequence of the charge transfer occurring when wires interact with metallic nanoparticles. While polyynes have semiconducting electronic properties, a more equalized system tends to a cumulene-like structure characterized by a nearly metallic behavior. The effect of different sp2 end groups in driving a semiconductor-to-metal transition is investigated by DFT calculations on a series of CAWs capped with different terminations. We discuss how the modulation of the structural, electronic, and vibrational properties of the sp-carbon chain toward the metallic wire is not trivial and requires a suitable chemical design of the end group and control of charge transfer. These results provide a guideline for the design of novel sp–sp2 hybrid carbon nanosystems with tunable properties, where graphene-like and polyyne-like domains are closely interconnected. The capability to tune the final electronic or optical response of the material makes these hybrid sp–sp2 systems appealing for a future all-carbon-based science and technology