Climate action: is coronavirus what we have been waiting for? (and now what?)

In the beginning of 2020, it looked like serious climate action was finally going to take place after decades of procrastination, but we are now inevitably leaving the transformation path. Abruptly (and remarkably), the coronavirus outbreak silenced ongoing efforts to protect climate, while also partly bringing carbon emissions to a halt. A global tragedy is still unfolding with vast social impacts and we are reaching a roundabout with several distinct exits. While embracing the uncertainty of current times, we try to envision likely transition pathways using the multi-level perspective. Climate activists, social innovators, dreamers, and networkers are expected to gain momentum and play critical roles in a sequence of co-evolutionary waves leading to a just, conscious, and regenerative recovery.info:eu-repo/semantics/publishedVersio

Efficient ion blocking in gaseous detectors and its application to gas-avalanche photomultipliers sensitive in the visible-light range

A novel concept for ion blocking in gas-avalanche detectors was developed, comprising cascaded micro-hole electron multipliers with patterned electrodes for ion defocusing. This leads to ion blocking at the 10^{-4} level, in DC mode, in operation conditions adequate for TPCs and for gaseous photomultipliers. The concept was validated in a cascaded visible-sensitive gas avalanche photomultiplier operating at atmospheric pressure of Ar/CH_{4} (95/5) with a bi-alkali photocathode. While in previous works high gain, in excess of 10^{5}, was reached only in a pulse-gated cascaded-GEM gaseous photomultiplier, the present device yielded, for the first time, similar gain in DC mode. We describe shortly the physical processes involved in the charge transport within gaseous photomultipliers and the ion blocking method. We present results of ion backflow fraction and of electron multiplication in cascaded patterned-electrode gaseous photomultiplier with K-Cs-Sb, Na-K-Sb and Cs-Sb visible-sensitive photocathodes, operated in DC mode.Comment: Proceeding paper to 10-th International Conference On Instrumentation For Colliding Beam Physics, Budker Institute of Nuclear Physics, Novosibirsk, Russia, February 28 - March 5, 2008, Submitted to NIMA, 5 pages, 7 figure

Parâmetros hematológicos e bioquímicos em três raças de cavalos de alta performance do Sul do Brasil

The hematological and biochemical parameters are useful tools for clinics and feeding management of athlete equines. The population of high performance horses consists of different breed groups, displaying specific phenotypic and metabolic characteristics related to the type of sport activity they perform. In the state of Rio Grande do Sul, in the South of Brazil, racing, jumping, polo, endurance, reigning, and dressage are the main activities. This study investigated the hemato-biochemical parameters in three high performance horse breeds from Southern Brazil. A total number of 154 horses belonging to the breeds Thoroughbred, Brasileiro de Hipismo, and Criollo, were selected for this study. Within each breed, samples were collected from males (n=12) and non-pregnant females (n=12) of two ages: 1 to 3 years of age (n=12) and over five years of age (n=12). Hematological (total count of erythrocytes and leukocytes, blood cell volume, hemoglobin, and differential count of leukocytes) and biochemical (lactate, fructosamine, glucose, cholesterol, total protein, albumin, globulins, fibrinogen, urea, calcium, magnesium, phosphorus, and enzymes LDH, AST, GGT, and CK) parameters were analyzed. Significant differences were observed in hematological and biochemical parameters, except for calcium and albumin, among breeds. There was no significant effect of age or sex within breed. This study shows that the local population, the breed and the type of sport activity are important variables to be considered in the analysis of blood parameters of horses.Os parâmetros hematológicos e bioquímicos são ferramentas que auxiliam na clínica e no manejo alimentar do eqüino atleta. Na população eqüina de alta performance existem diferentes grupos raciais que apresentam características fenotípicas e metabólicas específicas, relacionadas com o tipo de atividade esportiva que exercem. Atualmente, no Rio Grande do Sul (Sul do Brasil), são reconhecidas as modalidades esportivas de corrida, salto, polo, enduro, provas de rédeas e provas funcionais. O presente trabalho estudou os parâmetros hemato-bioquímicos em três raças de eqüinos de alta performance no Sul do Brasil. Um total de 154 animais das raças Puro Sangue Inglês, Brasileiro de Hipismo e Crioula foram selecionados para este estudo. Em cada grupo racial foram obtidas amostras de machos (n=12) e fêmeas não gestantes (n=12) e de duas faixas etárias: de 1 a 3 anos (n=12) e de mais de cinco anos (n=12). Foram analisados parâmetros hematológicos (contagem total de eritrócitos e leucócitos, hematócrito, hemoglobina e contagem diferencial de leucócitos) e bioquímicos (lactato, fructosamina, glicose, colesterol, proteína total, albumina, globulinas, fibrinogênio, uréia, cálcio, magnésio, fósforo e enzimas LDH, AST, GGT e CK). Foram observadas diferenças significativas nos parâmetros hematológicos e bioquímicos, exceto para cálcio e albumina, entre os grupos raciais. Não houve efeito significativo da idade e do sexo dentro da mesma raça. O presente trabalho mostra que o fator racial e o tipo de atividade esportiva são variáveis importantes que devem ser consideradas na análise de parâmetros sangüíneos em eqüinos

MHSP in reversed-biased operation mode for ion blocking in gas-avalanche multipliers

We present recent results on the operation of gas-avalanche detectors comprising a cascade of gas electron multipliers (GEMs) and Micro-Hole and Strip Plates (MHSPs) multiplier operated in reversed-bias (R-MHSP) mode. The operation mechanism of the R-MHSP is explained and its potential contribution to ion-backflow (IBF) reduction is demonstrated. IBF values of 4E-3 were obtained in cascaded R-MHSP and GEM multipliers at gains of about 1E+4, though at the expense of reduced effective gain in the first R- MHSP multiplier in the cascade.Comment: 23 pages, 8 figure

Micromegas operation in high pressure xenon: charge and scintillation readout

The operational characteristics of a Micromegas operating in pure xenon at the pressure range of 1 to 10 bar are investigated. The maximum charge gain achieved in each pressure is approximately constant, around 4x10^2, for xenon pressures up to 5 bar and decreasing slowly above this pressure down to values somewhat above 10^2 at 10 bar. The MM presents the highest gains for xenon pressures above 4 bar, when compared to other micropattern gaseous multipliers. The lowest energy resolution obtained for X-rays of 22.1 keV exhibits a steady increase with pressure, from 12% at 1bar to about 32% at 10 bar. The effective scintillation yield, defined as the number of photons exiting through the MM mesh holes per primary electron produced in the conversion region was calculated. This yield is about 2x10^2 photons per primary electron at 1 bar, increasing to about 6x10^2 at 5 bar and, then, decreasing again to 2x10^2 at 10 bar. The readout of this scintillation by a suitable photosensor will result in higher gains but with increased statistical fluctuations.Comment: 22 pages, 11 figure

Ion-induced effects in GEM & GEM/MHSP gaseous photomultipliers for the UV and the visible spectral range

We report on the progress in the study of cascaded GEM and GEM/MHSP gas avalanche photomultipliers operating at atmospheric pressure, with CsI and bialkali photocathodes. They have single-photon sensitivity, ns time resolution and good localization properties. We summarize operational aspects and results, with the highlight of a high-gain stable gated operation of a visible-light device. Of particular importance are the results of a recent ion-backflow reduction study in different cascaded multipliers, affecting the detector's stability and the photocathode's liftime. We report on the significant progress in ion-blocking and provide first results on bialkali-photocathode aging under gas multiplication.Comment: 6 pages, 8 figure

High-gain DC-mode operated Gaseous Photomultipliers for the visible spectral range

We shortly describe recent progress in photon detectors combining bi-alkali photocathodes and cascaded patterned gas-avalanche electron multipliers. It permitted the development and the first feasibility demonstration of high-gain gaseous photomultipliers sensitive in the visible spectral range, operated in DC mode with single-photon sensitivity.Comment: Proceedings to the 5th International Conference on New Developments In Photodetection 2008, Aix-les-Bains, France, June 15-20, 2008, submitted to NIM

Angiotensin-(1–7)/Mas axis integrity is required for the expression of object recognition memory

AbstractIt has been shown that the brain has its own intrinsic renin–angiotensin system (RAS) and angiotensin-(1–7) (Ang-(1–7)) is particularly interesting, because it appears to counterbalance most of the Ang II effects. Ang-(1–7) exerts its biological function through activation of the G-protein-coupled receptor Mas. Interestingly, hippocampus is one of the regions with higher expression of Mas. However, the role of Ang-(1–7)/Mas axis in hippocampus-dependent memories is still poorly understood. Here we demonstrated that Mas ablation, as well as the blockade of Mas in the CA1-hippocampus, impaired object recognition memory (ORM). We also demonstrated that the blockade of Ang II receptors AT1, but not AT2, recovers ORM impairment of Mas-deficient mice. Considering that high concentrations of Ang-(1–7) may activate AT1 receptors, nonspecifically, we evaluate the levels of Ang-(1–7) and its main precursors Ang I and Ang II in the hippocampus of Mas-deficient mice. The Ang I and Ang II levels are unaltered in the whole hipocampus of MasKo. However, Ang-(1–7) concentration is increased in the whole hippocampus of MasKo mice, as well as in the CA1 area. Taken together, our findings suggest that the functionality of the Ang-(1–7)/Mas axis is essential for normal ORM processing