5 research outputs found
Efeitos da dispersão e deposição de arsénio, cobre, chumbo e zinco na zona envolvente à mina de Neves-Corvo
A região de Neves-Corvo (37°34'13,5"N, 7°58’19,1”O) possui o mais importante
depósito de cobre de Portugal, sendo ainda um dos maiores do mundo. Situada a
15 km de Castro Verde, no Baixo Alentejo, esta mina produz essencialmente cobre,
estanho e zinco. A mineração constitui uma atividade extremamente poluente
alterando a composição da atmosfera, do solo, e águas quer subterrâneas ou
superficiais.
O objetivo deste trabalho é estudar a dispersão e deposição dos elementos (arsénio,
cobre, chumbo e zinco) provenientes da mineração, em folhas de plantas hortícolas
locais e em 44 amostras de solo num raio de 1,5 km. O material vegetal foi dividido
em dois grupos, com igual número de folhas de cada planta. Todas as folhas de um
dos grupos foram lavadas por água destilada, para remoção das poeiras. As
amostras de solo foram recolhidas até 10 cm de profundidade. No laboratório, as
amostras de solo foram peneiradas para retirar o material grosseiro e serem
homogeneizadas. Todas as amostras foram seguidamente secas em estufa a 60ºC
até obtenção de peso constante. A quantificação e análise dos elementos foi feita
através de um Thermo Scientific™ Niton™ XL3t GOLDD + XRF.
Observa-se que na maior parte das folhas não lavadas a quantidade de elementos é
maior que nas folhas lavadas. No entanto é nas folhas perenes da laranjeira que a
diferença se faz notar em todos os elementos, com diferenças de 45 % para o
arsénio, 23% para o cobre, 50% para o chumbo e 20% para o zinco. As 42 amostras
de solo provenientes de solos de zonas agrícolas mostraram uma média de 28.3 mg
de As kg-1, 77.7 mg de Cu kg-1, 21.9 mg de Pb kg-1 e 59.4 mg de Zn kg-1. Os valores
médios de arsénio e cobre estão acima dos valores de referências usados pela
Agencia Portuguesa do Ambiente (APA) (11 mg de As kg-1 e 62 mg de Cu kg-1).
Em duas amostras provenientes de duas aldeias próximas da mina (A-do-Corvo e
Neves da Graça), os valores de arsénio são superiores aos valores de referência para
zonas residenciais (18 mg de As kg-1). No caso da amostra de solo proveniente da
aldeia de A-do-Corvo, os valores de cobre são 9,77 vezes superiores aos valores de
referência (92 mg de Cu kg-1). Na observação de valores superiores aos estipulados
pela APA e sabendo que a Faixa Piritosa Ibérica (FPI) apresentam valores de fundo
geoquímico superiores, calcularam-se valores de referência locais. Com estes valores de referência obtiveram-se valores de corte, dos quais podemos
dizer efetivamente quais as zonas contaminadas. Foram realizados mapas
morfológicos onde estão visíveis as áreas com os valores de arsénio e cobre. Estas
áreas foram divididas em não contaminadas (Azul), incerteza (Verde) e
contaminadas (Vermelho). Concluiu-se que dos quatro elementos analisados nas
amostras de solo, o arsénio em especial e também o cobre apresentam
concentrações em alguns lugares, acima do valor de corte. Essas zonas poderão ser
passíveis de uma futura monotorização ou remediação.info:eu-repo/semantics/publishedVersio
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The persistence of cognitive biases in financial decisions across economic groups
Data availability:
All data will be posted open access via https://psyarxiv.com/mrxy6/ and in interactive form via https://public.tableau.com/app/profile/kai.ruggeri. We will post these only once an accepted version of all analyses is possible to avoid confusion based on version control.While economic inequality continues to rise within countries, efforts to address it have been largely ineffective, particularly those involving behavioral approaches. It is often implied but not tested that choice patterns among low-income individuals may be a factor impeding behavioral interventions aimed at improving upward economic mobility. To test this, we assessed rates of ten cognitive biases across nearly 5000 participants from 27 countries. Our analyses were primarily focused on 1458 individuals that were either low-income adults or individuals who grew up in disadvantaged households but had above-average financial well-being as adults, known as positive deviants. Using discrete and complex models, we find evidence of no differences within or between groups or countries. We therefore conclude that choices impeded by cognitive biases alone cannot explain why some individuals do not experience upward economic mobility. Policies must combine both behavioral and structural interventions to improve financial well-being across populations.This research was supported in part by the National Science Foundation (#2218595) and by Undergraduate Global Engagement at Columbia University. Additional support was provided to individual researchers from the Columbia University Office of the Provost, Masaryk University Centre for International Cooperation, and the Benjamin A. Gilman International Fund from the United States Department of State. This research was funded in part, by the UKRI [MR/N013468/1]
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The psychology and policy of overcoming economic inequality
Data and materials’ availability:
All data are publicly available for the survey data used (https://osf.io/njd62/) and from the UN Gender Inequality Index (https://hdr.undp.org/data-center/documentation-and-downloads). Financial transaction data were provided through an agreement with Columbia Business School.Recent arguments claim that behavioral science has focused – to its detriment – on the individual over the system when construing behavioral interventions. In this commentary, we argue that tackling economic inequality using both framings in tandem is invaluable. By studying individuals who have overcome inequality, “positive deviants,” and the system limitations they navigate, we offer potentially greater policy solutions.This research was supported in part by the National Science Foundation (no. 2218595) and by Undergraduate Global Engagement at Columbia University. Additional support was provided to individual researchers from the Columbia University Office of the Provost, Masaryk University Centre for International Cooperation, and the Benjamin A. Gilman International Fund from the United States Department of State
'Green revolution' genes encode mutant gibberellin response modulators.
World wheat grain yields increased substantially in the 1960s and 1970s because farmers rapidly adopted the new varieties and cultivation methods of the so-called 'green revolution'. The new varieties are shorter, increase grain yield at the expense of straw biomass, and are more resistant to damage by wind and rain. These wheats are short because they respond abnormally to the plant growth hormone gibberellin. This reduced response to gibberellin is conferred by mutant dwarfing alleles at one of two Reduced height-1 (Rht-B1 and Rht-D1) loci. Here we show that Rht-B1/Rht-D1 and maize dwarf-8 (d8) are orthologues of the Arabidopsis Gibberellin Insensitive (GAI) gene. These genes encode proteins that resemble nuclear transcription factors and contain an SH2-like domain, indicating that phosphotyrosine may participate in gibberellin signalling. Six different orthologous dwarfing mutant alleles encode proteins that are altered in a conserved amino-terminal gibberellin signalling domain. Transgenic rice plants containing a mutant GAI allele give reduced responses to gibberellin and are dwarfed, indicating that mutant GAI orthologues could be used to increase yield in a wide range of crop species
The robustness of mental accounting: a global perspective
This pre-registered work tests the replicability of seven studies covering the most important effects associated with mental accounting across 5,589 participants from 21 countries. Findings support the robustness of the original studies across time and culture, confirming the role of mental accounting as a critical driver of human decision-making