Adaptation opportunities for water security in Brazil

We sought to identify priorities and adaptation opportunities for water security across the various Brazilian biomes. With ever-growing demand and water-usage, future climate scenarios suggest that further water resources management constraints are to be endured throughout the next two decades. The unbalance between high-quality water demand and availability in a multisectoral usage context (e.g., domestic, industry, agribusiness) highlights the socio-ecological Nexus+ concept's relevance. In this context, the political and cross-institutional articulation and flexibility play a significant role in steering adaptative actions. These challenges in defining action plans, adequately addressed at a multiscale level with inherent climatic uncertainties, are yet to be overcome in Brazilian water resources management.  We sought to identify priorities and adaptation opportunities for water security across the various Brazilian biomes. With ever-growing demand and water-usage, future climate scenarios suggest that further water resources management constraints are to be endured throughout the next two decades. The unbalance between high-quality water demand and availability in a multisectoral usage context (e.g., domestic, industry, agribusiness) highlights the socio-ecological Nexus+ concept's relevance. In this context, the political and cross-institutional articulation and flexibility play a significant role in steering adaptative actions. These challenges in defining action plans, adequately addressed at a multiscale level with inherent climatic uncertainties, are yet to be overcome in Brazilian water resources management. Â

Planets Around Low-Mass Stars (PALMS). II. A Low-Mass Companion to the Young M Dwarf GJ 3629 Separated By 0.2"

We present the discovery of a 0.2" companion to the young M dwarf GJ 3629 as part of our high contrast adaptive optics imaging search for giant planets around low-mass stars with the Keck-II and Subaru telescopes. Two epochs of imaging confirm the pair is co-moving and reveal signs of orbital motion. The primary exhibits saturated X-ray emission, which together with its UV photometry from GALEX point to an age younger than ~300 Myr. At these ages the companion lies below the hydrogen burning limit with a model-dependent mass of 46 +/- 16 Mjup based on the system's photometric distance of 22 +/- 3 pc. Resolved YJHK photometry of the pair indicates a spectral type of M7 +/- 2 for GJ 3629 B. With a projected separation of 4.4 +/- 0.6 AU and an estimated orbital period of 21 +/- 5 yr, GJ 3629 AB is likely to yield a dynamical mass in the next several years, making it one of only a handful of brown dwarfs to have a measured mass and an age constrained from the stellar primary.Comment: Accepted for publication in Ap

Notes on disentangling of spectra II. Intrinsic line-profile variability due to Cepheid pulsations

The determination of pulsation velocities from observed spectra of Cepheids is needed for the Baade-Wesselink calibration of these primary distance markers. The applicability of the Fourier-disentangling technique for the determination of pulsation velocities of Cepheids and other pulsating stars is studied. The KOREL-code was modified to enable fitting of free parameters of a prescribed line-profile broadening function corresponding to the radial pulsations of the stellar atmosphere. It was applied to spectra of delta Cep in the H-alpha region observed with the Ondrejov 2-m telescope. The telluric lines were removed using template-constrained disentangling, phase-locked variations of line-strengths were measured and the curves of pulsational velocities obtained for several spectral lines. It is shown that the amplitude and phase of the velocities and line-strength variations depend on the depth of line formation and the excitation potential. The disentangling of pulsations in the Cepheid spectra may be used for distance determination

The Nexus+ approach applied to studies of Impacts, vulnerability and adaptation to climate change in Brazil

This paper aims to present the methodology developed within the Impacts, Vulnerability and Adaptation (IVA) to climate change component of the Fourth National Communication (4CN) of Brazil. The methodological choice of this 4CN involves the application of the nexus+ integrated approach, based on studies of impacts and vulnerabilities for water, energy, food and socio-environmental securities, in the different in the territories of Brazilian biomes, coastal areas and cities. For each of these securities it were identified the observed impacts; analysis of risk conditions; definition and assessments of integrated analysis of key impacts at territorial level; inventory, selection and analysis of adaption options in the context of Nexus+, identifying synergies and trade-offs. This process made possible an integrated assessment among the conditioning risk factors, impacts and interactions among proposed adaptation options.This paper aims to present the methodology developed within the Impacts, Vulnerability and Adaptation (IVA) to climate change component of the Fourth National Communication (4CN) of Brazil. The methodological choice of this 4CN involves the application of the nexus+ integrated approach, based on studies of impacts and vulnerabilities for water, energy, food and socio-environmental securities, in the different in the territories of Brazilian biomes, coastal areas and cities. For each of these securities it were identified the observed impacts; analysis of risk conditions; definition and assessments of integrated analysis of key impacts at territorial level; inventory, selection and analysis of adaption options in the context of Nexus+, identifying synergies and trade-offs. This process made possible an integrated assessment among the conditioning risk factors, impacts and interactions among proposed adaptation options

SECAS E OS IMPACTOS NA REGIÃO SUL DO BRASIL

Embora eventos de secas sejam menos frequentes na Região Sul, se comparado com outras regiões do Brasil, quando ocorrem impactam o abastecimento de água, produção agrícola e a geração de energia elétrica. Portanto, a avaliação dos impactos da seca no setor agrícola e nos recursos hídricos, são de extrema importância para a gestão de riscos nesta região. Neste estudo avaliou-se os principais eventos de secas e seus impactos entre 1998 a 2020 (maio) na Região Sul do Brasil. Para isto, foram utilizados índices de secas calculados a partir de dados de precipitação, vazão e dados derivados de satélite. De acordo com o Índice de Precipitação Padronizada (SPI), o evento mais severo de seca ocorreu no estado do Paraná em 2006. Como consequência, registrou-se valores de área agro-produtivas afetada acima de 80% e seca hidrológica excepcional na bacia hidrográfica afluente (BHA) à usina hidrelétrica (UHE) Segredo, segundo o Índice de Vazão Padronizada (SSFI), além de vazões afluentes abaixo do percentil 90 durante 50% do ano. Em Santa Catarina e no Rio Grande do Sul, os eventos de secas de maior severidade ocorreram em 2012/2013. Apesar disso, os percentuais de áreas agro-produtivas afetadas foram inferiores aos verificados para 2019/2020. Com relação aos recursos hídricos, o SSFI indicou seca excepcional na BHA ao reservatório da UHE Passo Real, e foi observada vazão abaixo do percentil 90 no primeiro semestre de 2012. No evento de seca 2019/2020, o primeiro trimestre de 2020 foi o mais crítico em termos de intensidade e expansão, como mostrado pelo Índice Integrado de Seca, em que 100% dos municípios de toda a região foram classificados em condição de seca. O impacto deste evento pode ser observado pelo SSFI da BHA ao reservatório da UHE Itaipu, com menores valores registrados a partir de janeiro de 2020. Este evento pode estar associado à influência da fase negativa da Oscilação Decadal do Pacífico e condições de neutralidade no Pacífico Equatorial

Near IR spectroscopy for the characterization of dispersion in polymer-clay nanocomposites

© 2015 Wiley-VCH Verlag GmbH & Co. KGaA. Since their potential has become widely recognized, one of the major research lines on polymer-clay nanocomposites has focused on the preparation of well-dispersed systems. Currently, there is an understanding that a high degree of dispersion, particularly exfoliation, of the nanoclay is required to improve the overall performance. Twin screw extrusion not only allows for control of the main variables (shear, stress and time), but also, due to the typical modular construction, offers a high degree of freedom in creating the adequate screw design and enables knowledgeable alteration of the barrel. These features offer a solid basis for the development and implementation of apt in-line/on-line monitoring techniques, able to follow up the evolution of dispersion of polymer-clay nanocomposites during processing. This chapter includs the validation, implementation, and application of a methodology based on inline near-infrared (NIR) spectroscopy for the characterization of the dispersion along the extruder axis. Overall, the results obtained confirm that NIR is a valid tool for the on-line characterization of these materials, offering the possibility of assessing in real time the clay dispersion, enabling proper corrective and/or optimization actions over the material characteristics in a timely manner.(undefined

Seasonal variations in the Amazon plume-related atmospheric carbon sink

The Amazon River plume is a highly seasonal feature that can reach more than 3000 km across the tropical Atlantic Ocean, and cover ∼2 million km². Ship observations show that its seasonal presence significantly reduces sea surface salinity and inorganic carbon. In the western tropical North Atlantic during April–May 2003, plume-influenced stations exhibited surface DIC concentrations lowered by as much as 563 μmol C kg⁻¹ (∼28%) and pCO₂ as low as 201 μatm. We combine our data with other data sets to understand the annual uptake and seasonal variability of the plume-related CO₂ sink. Using flux estimates from all seasons with monthly plume areas determined by satellite, we calculate the annual carbon uptake by the outer plume alone (28 < S < 35) to be 15 ± 6 TgC yr⁻¹. Diazotroph-supported net community production enhanced the air-sea CO₂ disequilibrium by 100x and reversed the typical CO₂ outgassing from the tropical North Atlantic. The carbon sink in the Amazon plume depends on climate-sensitive conditions that control river hydrology, CO₂ solubility, and gas exchange

The First Post-Kepler Brightness Dips of KIC 8462852

We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in October 2015, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor", which persist on timescales from several days to weeks. Our main results so far are: (i) there are no apparent changes of the stellar spectrum or polarization during the dips; (ii) the multiband photometry of the dips shows differential reddening favoring non-grey extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale <<1um, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term "secular" dimming, which may be caused by independent processes, or probe different regimes of a single process

Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.