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Water treatment technologies for removing priority pesticides.
No full textThe development of technologies to remove pesticides from environmental matrices is an important issue as they
may be toxic to the environment and human health. The objective of this review is to understand the treatability
of five selected pesticides including the main treatment processes and conditions employed worldwide to remove
them. Despite its widespread use in water treatment plants (WTP), conventional technologies alone were only
tested for atrazine and resulted in low average removal (up to 50 %). Several studies using advanced oxidation
processes have been successful for atrazine, but few experiments have been performed under practical conditions. Regarding reported efficiencies, 80 % of atrazine was degraded when conventional treatment was followed
by ozonation using aluminum sulfate and magnafloc LT 22 as coagulants and ozone as disinfectant. For acephate
and methamidophos, the use of titanium dioxide was the best treatment, leading to 87.7 % to 100 % removal in
laboratory-scale experiments. Anodic Fenton treatment and a combination of Fenton and ultrasound exhibited
high (99 and 100 %, respectively) carbofuran removal efficiencies. In terms of time and conditions tested, the
membrane anodic Fenton treatment was the best one, but large-scale application needs to be further evaluated.
In general, advanced oxidation processes are good complementary technologies. However, understanding the
fate and toxicity of the transformation by-products is crucial, as well as its applicability (economic and environmental sustainability) on a large scale
Self-organizing maps applied to declustering in preferential sampling.
No full textOs processos de amostragem na exploração mineral muitas vezes resultam em áreas preferencialmente amostradas, com a formação de agrupamentos, que podem surgir devido a alguns fatores, tais como condições de acessibilidade, valores de atributos e a estratégia de amostragem. Os agrupamentos afetam a inferência estatística da área. O objetivo deste artigo é propor uma nova abordagem para métodos de desagrupamento usando as redes de Kohonen, Self-Organizing Maps (SOM). As SOMs é um tipo de rede neural artificial usada para classificação não supervisionada. A metodologia atribui a cada amostra um peso para calcular a média desagrupada. A atribuição de peso para cada amostra em uma área é inversamente proporcional à área densamente amostrada. A média desagrupada é dada pela soma da multiplicação do peso com o valor do atributo de cada amostra. Portanto, a lógica de atribuição de pesos é semelhante ao método Cell Declustering, porém as SOMs identificam as áreas com margens não lineares, ao contrário do método Cell Declustering. Um estudo de caso é apresentado, usando o conjunto de dados de Walker Lake. A presente pesquisa não pretende substituir os métodos clássicos de desagrupamento, mas sim apresentar uma nova abordagem para um problema rotineiro na avaliação de reservas. Embora a matemática da técnica aplicada seja de fato complexa, os resultados podem ser promissores.Sampling processes in mineral exploration often result in preferentially sampled areas, with the formation of clustering. Some factors can cause areas to be preferentially sampled, accessibility conditions, attribute values, and the sampling strategy. Clustering impacts statistical inference of area. The objective of the present paper is to propose a new approach to declustering methods using Kohonen network, Self-Organizing Maps (SOM). SOM are a type of artificial neural network used for unsupervised classification. The methodology assigns each sample a weight to calculate the declustered mean. The assignment of weight to each sample in an area is inversely proportional to the densely sampled in area. The declustered mean is given by the sum of the weight multiplication with the attribute value of each sample. Therefore, the logic of assigning weights is similar to Cell Declustering method, but the delimitation of the densified areas is different. SOM identifies areas with non-linear margins, unlike the Cell Declustering method. A case study is presented, using the Walker Lake data set. The present research is not intended to replace classical declustering methods, but rather to present a new approach to a routine problem in reserve evaluation. Although the mathematics of the applied technique is indeed complex, the results can be promising
Influence of socioeconomic inequality on the distribution of COVID-19 hospitalizations and deaths in Brazilian municipalities, 2020 : an ecological study.
No full textObjetivo: analisar a influência da desigualdade socioeconômica na distribuição da covid-19 nos maiores
municípios brasileiros (> 100 mil habitantes), controlando, pelo efeito da infraestrutura hospitalar, comorbidades
e outras variáveis. Métodos: estudo ecológico sobre internações e óbitos por covid-19 em 2020; dados de
desfecho obtidos do Ministério da Saúde; a razão de incidência foi estimada via modelo linear generalizado.
Resultados: identificados 291.073 internações e 139.953 óbitos; encontrou-se maior taxa de mortalidade nos
municípios com maior população não branca (IC95% 1,01;1,16) e nos domicílios com mais de duas pessoas por
cômodo (IC95% 1,01;1,13); para ambos os desfechos, esgotamento sanitário foi protetivo (internações: IC95% 0,87;0,99
– óbitos: IC95% 0,90;0,99), e população em aglomerados subnormais revelou-se fator de risco (internações:
IC95% 1,01;1,16 – óbitos: IC95% 1,09;1,21) com interação, com a proporção de pessoas a receber auxílio emergencial
(internações: IC95% 0,88;1,00 – óbitos: IC95% 0,89;0,98). Conclusão: condições socioeconômicas afetaram o
adoecimento e morte por covid-19 no Brasil.Objective: to analyze the influence of socioeconomic inequality on COVID-19 distribution in larger Brazilian
municipalities, controlling for effect of hospital infrastructure, comorbidities and other variables. Methods:
this was an ecological study of COVID-19 hospitalizations and deaths in 2020; outcome data were obtained
from the Ministry of Health; incidence ratios were estimated using a generalized linear model. Results: we
identified 291,073 hospitalizations and 139,953 deaths; we found higher mortality rates in municipalities with a
higher proportion of non-White people (95%CI 1.01;1.16) and with more households with more than two people
per room (95%CI 1.01;1.13); presence of sewerage systems was protective for both outcomes (hospitalizations:
95%CI 0.87;0.99 – deaths: 95%CI 0.90;0.99), while a higher proportion of the population in subnormal housing
clusters was a risk factor (hospitalizations: 95%CI 1.01;1.16 – deaths: 95%CI 1.09;1.21), with this variable interacting
with the proportion of people receiving Emergency Aid (hospitalizations: 95%CI 0.88;1.00 – deaths: 95%CI
0.89;0.98). Conclusion: socioeconomic conditions affected illness and death due to COVID-19 in Brazil
Synthesis and application of an unprecedented bioadsorbent for removing arsenic from aqueous systems.
No full textA quaternary ammonium anion exchanger (SBTEA) was prepared from sugarcane bagasse (SB) employing an improved two-step synthesis method by chemical modification with epichlorohydrin (EPI) and triethylamine (TEA) using N,N-dimethylformamide as a solvent without catalyst. Two multivariate optimizations were utilized to determine optimum conditions for SBTEA synthesis using Doehlert experimental designs. The optimum synthesis conditions were: VEPI = 12.8 mL gSB− 1; VTEA = 22.0 mL gSB − 1; and T1 (etherification step) = T2 (amination step) = 100 ◦C. The chlorine and nitrogen contents of the SBTEA produced under these conditions with a 21-fold increase in the synthesis scale (SBTEA-LS) were 4.2 ± 0.1% and 1.485 ± 0.007%, respectively. The 13C Multi-CP SS NMR revealed that 1.7 quaternary ammonium groups were introduced for 10 cellobiose units. SBTEA-LS was used to remove As(V) from contaminated groundwater samples with high removal efficiency (95 ± 4%), even with strong competitors such as SO42− . The interactions involved in the adsorption were investigated through macroscopic and microscopic measurements, which suggested that the adsorption of As(V) on SBTEA-LS occurred mainly by ion exchange. Desorption experiments proved that SBTEA-LS could be efficiently regenerated (Edes > 90%) using an HNO3 solution, reducing operating costs and favoring technology upscaling
Acute and chronic effects of strength training on plasma levels of adipokines in man.
No full textAdipose tissue is specialized cells that produce and release adipokines. Exercise may modulate adipokine production in adipocytes. The aim of this longitudinal study was to evaluate the acute and chronic effects of strength training (ST) on plas- ma levels of adiponectin, leptin, and resistin. Twelve untrained young male participants (23.42 ± 2.67 years) were selected. The training protocol consisted of 3 exercises, with 3 sets of 65% of 1RM (one-repetition maximum) with pause of 90 s be- tween sets with duration of 5 s/repetition (2 s conc/3 s ecc), 3 times a week for 10 weeks. Blood was collected at four time points: before and after the first ST session and before and after the last ST session. The comparisons between adipokine levels before and after the same training session showed acute changes, while the comparisons between levels before or after the first session versus before or after the last session revealed chronic alterations. ST increased adiponectin levels after the first exercise session in comparison to levels before this session [50 952 (46 568–51 894) pg/mL vs. 52 981 (49 901–54 467) pg/mL, p = 0.019]. Similar differences were observed for resis- tin levels, which were higher after the last session compared to before [4 214.4 ( ± 829) pg/mL vs. pre-S30 2 251.3 ( ± 462.2) pg/mL, p = 0.0008] and in the comparison between after the last and after the first ST sessions [4 214.4 ( ± 829.0) pg/mL vs. 1 563.7 ( ± 284.8) pg/mL, p = 0.004]. Leptin levels acutely changed in the last training session. ST produced acute and chronic changes in plasma adipokines
The use of an adjuvant system improves innate and adaptive immune response when associated with a Leishmania (Viannia) braziliensis antigen in a vaccine candidate against L. (Leishmania) infantum infection.
No full textBackground: The adjuvants’ optimal dose and the administration route can directly influence the epitope recognition patterns and profiles of innate response. We aimed to establish
the effect and the optimal dose of adjuvant systems for proposing a vaccine candidate to be employed with Leishmania (Viannia) braziliensis. Methods: We evaluated the adjuvants saponin (SAP),
monophosphoryl lipid A (MPL) and resiquimod (R-848) isolated and combined as adjuvant systems
in a lower dose corresponding to 25%, 33%, and 50% of each adjuvant total dose. Male outbred
BALB/c mice were divided into 13 groups, SAP, MPL, and R-848 isolated, and the adjuvant systems
SAP plus MPL (SM), SAP plus R-848 (SR), and MPL plus R-848 (MR). Results: SM50 increased levels
of all chemokines analyzed and TNF production, while it presented an increased inflammatory cell
infiltrate in the skin with macrophage recruitment. Thus, we proposed a vaccine candidate employing
L. (V.) braziliensis antigen associated with the SM adjuvant system against experimental L. (Leishmania)
infantum challenge. We observed a significant increase in the frequency of cells expressing the central
and effector memory CD4+ T cells phenotype in immunized mice with the LBSM50. In the liver, there
was a decreased parasite load when mice received LBSM50. Conclusions: When combined with L. (V.)
braziliensis antigen, SM50 increases TNF and IFN-γ, which generates central and effector memory
CD4+ T cells. Therefore, using an adjuvant system can promote an effective innate immune response
with the potential to compose future vaccines
Application of an experimental approach to the investigation of cross linguistic influence in L2 and L3 learners
No full textA pesquisa investiga a Influência Linguística Cruzada (ILC) objetivando identificar
características do fenômeno que a produz, partindo da distância entre as línguas e direção da influência.
Para tanto, analisa a produção escrita e oral de nove sujeitos multilíngues, aprendizes de língua estrangeira,
realizada em condições experimentais, mediante a qual foram investigadas as hipóteses: (i) a distância entre
as línguas está correlacionada à ILC e (ii) a direção da influência é dependente da distância. Do
experimento, extraíram-se dados da produção dos sujeitos em quatro línguas, averiguando as hipóteses da
pesquisa. Os resultados sugerem uma correlação entre a distância e a ILC. Já a direção da influência não se
correlaciona necessariamente com a direção do aprendizado (L1 à Ln).The research investigates the Cross Linguistic Influence (CLI) aiming to identify characteristics
of the phenomenon that produces it, starting from the distance between the languages and the direction of
the influence. To this end, it analyzes the written and oral production of nine multilingual subjects, foreign
language learners, carried out under experimental conditions, through which the hypotheses were
investigated: (i) the distance between the languages is correlated to the ILC and (ii) the direction of
influence is dependent on distance. From the experiment, data on the subjects' production in four languages
were extracted, verifying the research hypotheses. The results suggest a correlation between distance and
ILC. The direction of influence is not necessarily correlated with the direction of learning (L1 to Ln)
O Conselho Internacional das Treze Avós Nativas e a prática historiográfica no mundo pós coronário.
No full textPrograma de Pós-Graduação em História. Departamento de História, Instituto de Ciências Humanas e Sociais, Universidade Federal de Ouro Preto.Esta tese de doutorado em História traz como temática um movimento
contemporâneo de mulheres chamado Conselho Internacional das Treze Avós
Nativas. Destacando a singularidade das operatórias metodológicas pautadas nas
sophyas africanas e indígenas, esse Conselho foi interpretado enquanto um fazer
político que, através de práticas performáticas rituais, terapêuticas e discursivas,
dissocia o existir da Terra do paradigma do desenvolvimento (tão próximo da
necropolítica) e o vincula àquele do Buen Vivir. Portanto, a tese aborda, de forma
ampla, cura aos males que, advindos do colonialismo/da colonialidade,
subalternizam os corpos colonizados. Essa cura está presente tanto no fazer
político das Avós quanto na Capoeira, cujas potencialidades epistêmicas e
filosóficas também são abarcadas nas páginas que seguem. Dessa maneira, a
trabalho é uma tentativa de contribuir para formulação de uma historiografia onde a
figura feminina – inclusive negra e ameríndia –, enquanto agente basilar de
memórias (inclusive de sonhos), ancestralidades (com seus enunciados
proféticos), saberes-fazeres de medicinas tradicionais, afetividades e religiosid-
ades, apareça como protagonista tanto da ação histórica/política quanto de uma
escrita histórica de ―encruzilhada‖ e ―macumbeira‖.This doctoral thesis in History focuses on a contemporary women's movement
called the International Council of Thirteen Native Grandmothers. Highlighting the
singularity of the methodological operations based on African and indigenous
sophias, this Council was interpreted as a political action that, through ritual,
therapeutic and discursive performative practices, dissociates the existence of
the Earth from the paradigm of development (so close to necropolitics/Ikupolitics)
and links it to Buen Vivir. Therefore, the thesis broadly addresses the cure for the
ills that, arising from colonialism/coloniality, subordinate colonized bodies. This
cure is present both in the political activities of the Avós and in Capoeira, whose
epistemic and philosophical potentialities are also covered in the pages that
follow. In this way, the work is an attempt to contribute to the formulation of a
historiography where the female figure – including black and Amerindian –, as a
basic agent of memories (including dreams), ancestries (with their prophetic
statements), medical know-how traditions, affections and religiosities, appear as
protagonists of both the historical/political action and of a historical writing of
―encruzilhada‖ and ―macumbeira‖
Acontecimento e testemunho jornalístico : uma análise dos livros "Olga" e "Maria Bonita: sexo, violência e mulheres no cangaço".
No full textPrograma de Pós-Graduação em Comunicação. Instituto de Ciências Sociais Aplicadas, Universidade Federal de Ouro Preto.Esta dissertação tem, como objeto de pesquisa, os livros “Olga” (2022), de Fernando Morais, e
“Maria Bonita: sexo, violência e mulheres no cangaço” (2018), de Adriana Negreiros. Nosso
objetivo é compreender de que modo as duas biografias jornalísticas puderam oferecer uma
segunda vida a suas personagens, uma vida simbólica (QUÉRÉ, 2012), bem como entender em
que medida essa segunda vida traz à tona memórias ignoradas ou excluídas devido a violências
de gênero. Optamos pela análise de narrativa como nossa metodologia e definimos dois
operadores metodológicos: a relação entre repórter e fontes; e a relação entre repórter e
biografada, com inspiração no trabalho de Dayane Barretos (2017) e Ticiane Alves (2021). No
primeiro deles, temos, como eixo operador, o testemunho na mídia (FROSH, PINCHEVSKI,
2009), no qual investigamos os processos de produção das biografias, buscando compreender
como os autores se apropriam de relatos testemunhais. No segundo operador metodológico,
temos, como eixo operador, o testemunho pela mídia (FROSH, PINCHEVSKI, 2009), no qual
investigamos a reconstrução da experiência pelas narrativas construídas e a afetação causada
por elas. Percebemos que os livros “Olga” e “Maria Bonita” oferecem uma segunda vida às
suas personagens ao testemunharem, a partir da atividade jornalística, os acontecimentos que
permearam a vida de ambas as mulheres. Tanto Morais quanto Negreiros, a partir de suas
experiências relacionais, enquanto jornalistas, assumem uma postura ativa na dinâmica
testemunhal e constituem, através da narrativa, os seus testemunhos. Os dois livros, além de
evidenciar como o jornalismo opera em meio às disputas de narrativas, dão pistas sobre os
modos de apropriação do testemunho do outro.This dissertation has, as objects of research, the books “Olga” (2022), by Fernando Morais, and
“Maria Bonita: Sex, Violence and Women in Cangaço” (2018), by Adriana Negreiros. Our goal
is to understand how the two journalistic biographies were able to provide a second life to their
characters, a symbolic life (QUÉRÉ, 2012), as well as to understand to which extent this second
life brings up memories that were ignored or excluded due to gender violence. We have opted
for narrative analysis as our methodology and defined two methodological operators: the
relationship between the reporter and their sources; and the relationship between the reporter
and their subject, inspired by the work of Dayane Barretos (2017) and Ticiane Alves (2021). In
the first one, we have, as an operating axis, the media testimony (FROSH, PINCHEVSKI,
2009), in which we investigate the production processes of biographies, seeking to understand
how the authors appropriate testimonial reports. In the second methodological operator, we
have, as an operating axis, the witnesses in the media (FROSH, PINCHEVSKI, 2009), in which
we investigate the reconstruction of experience through constructed narratives and the effect
caused by them. We realized that the books “Olga” and “Maria Bonita” provide a second life
to their characters by witnessing, from the journalistic activity, the events that permeated the
lives of both women. Both Morais and Negreiros, based on their relational experiences as
journalists, take on an active role in the testimonial dynamics and constitute, through the
narrative, their testimonies. The two books, in addition to showing how journalism operates in
the midst of narrative disputes, lay out clues about the ways of appropriating the testimony of
the other
A historicidade do transitório na ficção contemporânea Americanah, de Chimamanda Ngozi Adichie.
No full textPrograma de Pós-Graduação em História. Departamento de História, Instituto de Ciências Humanas e Sociais, Universidade Federal de Ouro Preto.Nesta pesquisa, procuramos investigar de que maneira a ficção Americanah, de Chimamanda
Ngozi Adichie, lida com o passado e a História. Argumentamos que Chimamanda Adichie
encena uma historicidade do transitório ao resgatar a visibilidade e a função moral do discurso
romanesco, com personagens moralmente verossímeis e cuja relação com o enredo é definida
pelo trânsito entre Terceiro Mundo e Ocidente. O incessante vai e vem entre memória,
vivência e experiência que nos constitui enquanto sujeitos históricos é encenado a partir das
situações e experiências de personagens negras e africanas transitando entre Terceiro Mundo e
Ocidente: dotados de consciências às quais temos acesso irrestrito, os protagonistas de
Americanah figuram um ângulo de observação sobre a História que se, por um lado, explicita
a condição subalterna do Terceiro Mundo, por outro, remete ao questionamento pós-colonial
sobre quem é e quem pode ser o sujeito da cultura. Em seguida, procuramos mostrar o
processamento desta historicidade do transitório na forma da narrativa. Argumentamos, então,
que a forma clássica do romance convive com uma forte aspiração à referencialidade,
identificada nas nuances entre protagonista e autora e no blog onde a protagonista ensaia o
choque com sua experiência do transitório.We aim to investigate in this research how the fiction Americanah, by Chimamanda Ngozi
Adichie, deals with the past and History. We argue that Chimamanda Adichie, by rescuing the
visibility and moral function of the novelistic discourse, with morally credible characters
whose relationship with the plot is defined by the transit between the Third World and the
West, stages a historicity of the transitory. The incessant back and forth between memory,
living and experience that constitutes us as historical subjects is staged from the situations and
experiences of black and African characters transiting between Third World and the West:
endowed with consciences to which we have unrestricted access, the protagonists of
Americanah figure an angle of observation on History that, on the one hand, makes explicit
the subaltern condition of the Third World, on the other, refers to the postcolonial questioning
about who is and who can be the subject of culture and knowledge.Then, we try to show the
processing of this historicity of the transitory in the form of the narrative. Eventually, we
argue that the classical form of the novel coexists with a strong aspiration to referentiality,
identified in the nuances between protagonist and author and in the blog where the protagonist
rehearses the clash with her experience of the transitory