Mass Spectrometry Based Molecular 3D-Cartography of Plant Metabolites

Plants play an essential part in global carbon fixing through photosynthesis and are the primary food and energy source for humans. Understanding them thoroughly is therefore of highest interest for humanity. Advances in DNA and RNA sequencing and in protein and metabolite analysis allow the systematic description of plant composition at the molecular level. With imaging mass spectrometry, we can now add a spatial level, typically in the micrometer-to-centimeter range, to their compositions, essential for a detailed molecular understanding. Here we present an LC-MS based approach for 3D plant imaging, which is scalable and allows the analysis of entire plants. We applied this approach in a case study to pepper and tomato plants. Together with MS/MS spectra library matching and spectral networking, this non-targeted workflow provides the highest sensitivity and selectivity for the molecular annotations and imaging of plants, laying the foundation for studies of plant metabolism and plant-environment interactions

Comunicación y respuestas al desafío climático en Uruguay

Uruguay aprobó su Política Nacional de Cambio Climático en 2017. El mismo año se publicó la Primera Contribución Determinada a Nivel Nacional al Acuerdo de París, que traza objetivos específicos para la reducción o gestión de emisiones de gases de efecto invernadero en diversos sectores, así como medidas a tomar en torno a la mitigación y a la adaptación ante el cambio climático. Cinco años después, el proyecto de investigación “Comunicación y respuestas al desafío climático” se propuso analizar distintas manifestaciones de la conversación pública ambiental para evaluar en qué medida dialoga con la respuesta institucional elaborada por Uruguay ante el problema. El análisis estadístico de la relación entre consumo de medios y actitudes climáticas con datos de encuestas de opinión pública descubre una asociación significativa entre el uso de YouTube y la aceptación de la importancia del cambio climático, así como entre la autopercepción de estar informado sobre el tema y la conciencia del problema. En el segmento de los adultos jóvenes -activistas y no activistas-, estudiado con la técnica cualitativa del grupo de discusión, el cambio climático no es el problema ambiental más preocupante y su plataforma de referencia para estos temas es principalmente Instagram, aunque consumen medios periodísticos incluso en sus formatos tradicionales, donde reportan información suficiente sobre la problemática ambiental. El análisis de la prensa digital uruguaya revela el predominio de un encuadre político del cambio climático, seguido de cerca por el económico, y la ausencia en la cobertura de más de la mitad de las medidas establecidas por Uruguay para cumplir con el Acuerdo de París. Energía y agro son los sectores más asociados al cambio climático. El discurso de influenciadores no tradicionales -influencers- uruguayos en Instagram refiere marginalmente al cambio climático y las medidas que encuentran lugar son las referidas a la protección de fauna y bosques nativos.Uruguay approved its National Climate Change Policy in 2017. That same year, the First Nationally Determined Contribution to the Paris Agreement was published, which outlines specific objectives for reducing or managing greenhouse gas emissions in various sectors, as well as measures to be taken regarding mitigation and adaptation to climate change. Five years later, the research project "Communication and responses to the climate challenge" set out to analyze different manifestations of the environmental public conversation to assess to what extent it links with the institutional response developed by Uruguay to the problem. Statistical analysis of the relationship between media consumption and climate attitudes, with data from public opinion surveys, reveals a significant association between the use of YouTube and the acceptance of the importance of climate change. Also, between the self-perception of being informed about the subject and awareness of the problem. In the segment of young adults -activists and non-activists- studied with the qualitative method of the focus group, climate change is not the most worrying environmental problem, and their reference platform for these issues is mainly Instagram. However, they consume journalistic media even in traditional formats, where they find insufficient information on environmental problems. The analysis of the Uruguayan digital press reveals the predominance of a political framing of climate change, closely followed by the economic one, and the absence in the coverage of more than half of the measures established by Uruguay to comply with the Paris Agreement. In press coverage, energy and agriculture are the sectors most associated with climate change. The discourse of non-traditional Uruguayan influencers -influencers- on Instagram marginally refers to climate change, and the measures that find a place are those referring to the protection of fauna and native forests

Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio to Q^2 = 8.5 GeV^2

Among the most fundamental observables of nucleon structure, electromagnetic form factors are a crucial benchmark for modern calculations describing the strong interaction dynamics of the nucleon's quark constituents; indeed, recent proton data have attracted intense theoretical interest. In this letter, we report new measurements of the proton electromagnetic form factor ratio using the recoil polarization method, at momentum transfers Q2=5.2, 6.7, and 8.5 GeV2. By extending the range of Q2 for which GEp is accurately determined by more than 50%, these measurements will provide significant constraints on models of nucleon structure in the non-perturbative regime

Search for effects beyond the Born approximation in polarization transfer observables in e⃗p\vec{e}p elastic scattering

Intensive theoretical and experimental efforts over the past decade have aimed at explaining the discrepancy between data for the proton electric to magnetic form factor ratio, $G_{E}/G_{M}$, obtained separately from cross section and polarization transfer measurements. One possible explanation for this difference is a two-photon-exchange (TPEX) contribution. In an effort to search for effects beyond the one-photon-exchange or Born approximation, we report measurements of polarization transfer observables in the elastic $H(\vec{e},e'\vec{p})$ reaction for three different beam energies at a fixed squared momentum transfer $Q^2 = 2.5$ GeV$^2$, spanning a wide range of the virtual photon polarization parameter, $\epsilon$. From these measured polarization observables, we have obtained separately the ratio $R$, which equals $\mu_p G_{E}/G_{M}$ in the Born approximation, and the longitudinal polarization transfer component $P_\ell$, with statistical and systematic uncertainties of \Delta R \approx \pm 0.01 \mbox{(stat)} \pm 0.013 \mbox{(syst)} and \Delta P_\ell/P^{Born}_{\ell} \approx \pm 0.006 \mbox{(stat)}\pm 0.01 \mbox{(syst)}. The ratio $R$ is found to be independent of $\epsilon$ at the 1.5% level, while the $\epsilon$ dependence of $P_\ell$ shows an enhancement of $(2.3 \pm 0.6)$ relative to the Born approximation at large $\epsilon$

American Gut: an Open Platform for Citizen Science Microbiome Research

McDonald D, Hyde E, Debelius JW, et al. American Gut: an Open Platform for Citizen Science Microbiome Research. mSystems. 2018;3(3):e00031-18

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe