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Platformed listening in podcasting : an approach from material and scales potentials.
No full textThis article proposes to investigate delineations of the audience in podcasting in streaming media ecology. To meet this objective, we highlight the scales between contents, circulation, and consumption of podcasts in platformization contexts. We observe these relationships from an intersectional approach that involves spaces between codes, contents and software to understand the dynamics of interrelationships between contents and its flows which are associated with the emergence of varied audiences, derived from listening practices, characterized by binge listening; fidelity strategies; hybrid recommendation practices, playlists and cross-device consumption in multiplatform architecture
Exposição ao frio e seus efeitos na expressão gênica do coração de camundongos alimentados com high-fat diet.
No full textPrograma de Pós-Graduação em Saúde e Nutrição. Escola de Nutrição, Universidade Federal de Ouro Preto.A melanopsina (OPN4) é um fotorreceptor e termo sensor cuja expressão é
observada em vários órgãos e tecidos, sendo o coração altamente expresso. Além
disso, a expressão dos canais de potencial receptor transitório (TRP) parece estar
associada à expressão de OPN4 na retina e supostamente no coração. Partimos da
hipótese que a OPN4, juntamente com os canais TRP no coração, atuam
monitorando as variações de temperatura interna através do sangue proveniente dos
pulmões, possivelmente promovendo a liberação e expressão de seus principais
hormônios, os peptídeos natriuréticos (NPs). Fatores como a temperatura do
ambiente e alimentação desiquilibrada, prejudicam a homeostase cardíaca,
causando efeitos prejudiciais na sua estrutura e função, potencialmente
desencadeando doenças cardiovasculares. Portanto, o objetivo do estudo é avaliar
os efeitos da exposição ao frio e a ausência do canal TRPA1 sobre a expressão
gênica de Opn4, Trpv1, Trpa1, Trpm8, Nppa e Nppb, em átrios e ventrículos do
coração de camundongos alimentados com high-fat diet. Foram utilizados 24
camundongos machos C57BL/6J e Trpa1 KO, divididos em 4 grupos experimentais e
expostos a temperaturas de 30°C e 22°C. Os resultados de PCR quantitativo
indicaram que a expressão de Opn4 nos átrios, à 30°C foi reduzida no grupo Trpa1
KO, em 22°C houve aumento na expressão do gene no mesmo grupo e, em
ventrículos não apresenta diferenças significativas. Quanto aos canais TRP, no gene
Trpv1 não encontramos diferenças significativas. Trpa1 átrios não houve diferenças
significativas, ventrículos à 22°C indicaram redução na expressão. Trpm8 átrios, à
30°C temos redução da expressão do gene no grupo Trpa1 KO, à 22°C resultou em
redução na expressão em camundongos C57BL/6J, enquanto, que no grupo Trpa1
KO, houve aumento da expressão. Já em ventrículos, à 30°C resultou em aumento
na expressão de Trpm8 no grupo Trpa1 KO e, em C57BL/6J aumento na expressão
à 22°C. Nos NPs, a expressão de Nppa não apresentou diferenças significativas.
Nppb em átrios, indicou redução na expressão à 22°C, tanto em C57BL/6J como
Trpa1 KO. Já em ventrículos, Nppb não apresentou diferenças significativas.
Podemos concluir que a OPN4 e os canais TRP possivelmente possam estar
atuando como termo sensores no coração, e as flutuações de temperatura afetam a
expressão dos NPs nas câmaras cardíacas.Melanopsin (OPN4) is a photoreceptor and thermosensor whose expression is
observed in various organs and tissues, with the heart being highly expressed.
Furthermore, the expression of transient receptor potential (TRP) channels appears
to be associated with OPN4 expression in the retina and putatively in the heart. We
start from the hypothesis that OPN4, together with TRP channels in the heart, act by
monitoring variations in internal temperature through blood from the lungs, possibly
promoting the release and expression of its main hormones, natriuretic peptides
(NPs). Factors such as environmental temperature and an unbalanced diet impair
cardiac homeostasis and have harmful effects on its structure and function,
potentially triggering cardiovascular diseases. Therefore, the objective of this study
was to evaluate the effects of cold exposure and the absence of the TRPA1 channel
on the gene expression of Opn4, Trpv1, Trpa1, Trpm8, Nppa, and Nppb in the atria
and ventricles of the heart of mice fed a high-fat diet. 24 male C57BL/6J and Trpa1
KO mice were used, divided into 4 experimental groups, and exposed to
temperatures of 30°C and 22°C. The results of quantitative PCR indicated that the
expression of Opn4 in the atria at 30°C was reduced in the Trpa1 KO group, whereas
at 22°C, there was an increase in gene expression in the same group and, in the
ventricles, there were no significant differences. As for TRP channels, in the Trpv1
gene we did not find significant differences. Trpa1 atria there were no significant
differences, ventricles at 22°C indicated a reduction in expression. Trpm8 atria, at
30°C we have a reduction in gene expression in the Trpa1 KO group, at 22°C it
resulted in a reduction in expression in C57BL/6J mice, while in the Trpa1 KO group,
there was an increase in expression. In the ventricles, 30°C resulted in an increase in
Trpm8 expression in the Trpa1 KO group and, in C57BL/6J, an increase in
expression at 22°C. In NPs, Nppa expression did not show significant differences.
Nppb in the atria indicated reduced expression at 22°C in both C57BL/6J and Trpa1
KO mice. In the ventricles, Nppb levels did not show significant differences. We can
conclude that OPN4 and TRP channels may act as thermal sensors in the heart, and
temperature fluctuations affect the expression of NPs in the heart chambers
Alkaline activation for production of slag-based binders from the manufacture of manganese ferroalloys.
No full textThe growing demand for sustainable development across different sectors is creating opportunities for research and development of products that incorporate waste materials in their production processes. One of the technologies that has gained prominence in this regard is the alkaline activation process, known for its low energy consumption and environmentally sustainable characteristics. In this sense, this work presents an evaluation of the application of slag generated in a manganese ferroalloy manufacturing plant as a precursor to alkali-activated binders. Grounded
silico-manganese slag and NaOH at different molarities were used to prepare samples, which were then cured at room temperature (25 ± 2 °C). The rheological properties of the pastes and the technological properties of compressive strength and water absorption were analyzed. In addition, microstructural analysis was performed using XRD, TG/DTA, SEM/EDS, and FTIR. The results showed that the shear stress increases with NaOH molarity, and viscosities are higher for the paste with the lowest molarity. The maximum 91-day compressive strength of 14.4 MPa was achieved with a 6 M solution, and for this condition, the mass loss was 0.2%. Integrating SEM micrographs with TG/DTA, XRD, and FTIR analysis supports the hypothesis of gel phase precipitation during the synthesis of the alkali-activated binder. Thus, incorporating this slag into the production of an alkali-activated binder demonstrates the potential to revitalize this manufacturing process, which could lead to the adoption of clean and environmentally sustainable technologies in industrial processes
Unravelling magmatic-hydrothermal processes at Salobo and GT-46 IOCG deposits, Carajás mineral province, Brazil : constraints from whole-rock geochemistry and trace elements in apatite.
No full textThe iron oxide-copper-gold (IOCG) deposits of the northern portion of the Carajás Province, Amazonian Craton, Brazil, were primarily formed at the 2.5 Ga IOCG event. These deposits commonly exhibit wide Fe–K hydro-thermal alteration halos (i.e., almandine-grunerite-biotite-magnetite) and display a temporal and spatial association with the 2.5 Ga granitic bodies, particularly in the GT-46 and in the world-class Salobo deposit. However, this association still lacks investigation concerning the metallogenic influence of the 2.5 Ga granitic bodies in the IOCG formation. Within these deposits, ca. 2.5 hydrothermally altered granites are recognized and include the Old Salobo, at the Salobo deposit, and G1 and G2, at the GT-46 deposit. Whole-rock geochemistry combined with petrography has pointed out that the G1 and Old Salobo are represented by granites to monzogranites, ferroan, metaluminous to weakly peraluminous with negative Eu anomaly. On the contrary, the G2 granite seems to represent a distinct body with granite composition, ferroan, metaluminous to weakly peraluminous with positive Eu anomaly. This granite exhibit pegmatitic textures, high Sr/Y ratios and listric-shaped normalized REE pat- terns, which suggest crystallization under high water contents. These granites primarily plots in the field of the volcanic arc granites, though some shifts towards to syn-collisional granites are observed. Effects of hydro-thermal alteration are commonly seen in these granites both in textural aspects and geochemistry. Apatite mineral chemistry studies shows that magmatic signature in apatite is preserved in the G2 granite (G2core apatite), Old Salobo granite (OSA) and in the GT-46 ore zone (OZGT-A apatite), represented by enrichment in LREE and negative Eu anomaly. Hydrothermally altered apatite is recognized in the Old Salobo (OSB) and G2 granite (G2rim) and in the ore zone of GT-46 deposit and (OZGT-B) with depletion in LREE, which suggest that the same fluid might have affected both deposits. Truly hydrothermal apatite crystals from the Salobo and GT-46 ore zones shows high (Eu/Eu*)N values, indicative of high oxygen fugacity and alkaline fluids. Strong HREE depletion of the apatite grains from the central zone of the deposits suggest coeval almandine crystallization in the Fe–K alteration halos and evolved hydrothermal fluids. These results indicate that magmatic and hydro-thermal process coexist in the IOCG deposits from the northern sector of Carajás Province. This might suggest that the 2.5 Ga IOCG deposits from the Carajas ́ Province can have formed during the development of wide magmatic-hydrothermal systems
Um peso e várias medidas : uma análise global da avaliação de leitura do PISA em comparação com o SAEB.
No full textThe mediating role of sun exposure on the association between sedentary behavior and sleep quality : a population-based crosssectional study.
No full textTratamento de água por plasma não-térmico para inativação de Escherichia coli.
No full textPrograma de Pós-Graduação em Engenharia Ambiental. Núcleo de Pesquisas e Pós-Graduação em Recursos Hídricos, Universidade Federal de Ouro Preto.A crescente preocupação com a disponibilidade e qualidade da água potável impulsionou
pesquisas em tecnologias avançadas de tratamento. Entre elas, o tratamento de água por
plasma não-térmico surge como uma abordagem promissora para inativar microrganismos e
assegurar a segurança hídrica. Este estudo investigou três configurações de plasma não-
térmico - Ponta-Plano, Plano-Plano e Dupla Ponta-Plano - analisando suas propriedades
distintivas de comportamento. Além disso, examinou a sobrevivência de colônias de E. coli
após o tratamento, identificando parâmetros-chave do sistema, como potência de entrada,
tempo de operação, gás de alimentação e taxa de fluxo. Esses parâmetros controlam
diretamente o desempenho e eficácia do sistema. O estudo também investiga parâmetros
físico-químicos relevantes para avaliar a qualidade da água tratada por plasma não-térmico,
considerando os padrões de qualidade estabelecidos para padrão de potabilidade. O reator
Ponta-Plano por sua menor tensão de ruptura na formação da descarga elétrica com plasma de
argônio, demonstrou estabilidade pela coloração intensa durante a operação. Desde os
primeiros testes, o reator demonstrou hiperatividade, independentemente do tempo e
voltagem, indicando agitação de partículas de elétrons e desencadeando reações químicas
crescentes. Sua notável produtividade em bolhas sugere uma maior produção de espécies
químicas no meio. Um novo delineamento experimental superou desafios e otimizou
condições operacionais. Apesar da análise estatística não indicar significância para tipo de gás
e vazão, observações específicas reforçam a superioridade do plasma de O2. A tendência
positiva no tempo de tratamento e a relevância destacada da variável "Tensão" minimiza a
necessidade de otimização. Esses resultados orientam futuras investigações para a aplicação
eficaz do plasma não térmico na inativação bacteriana.The growing concern about the availability and quality of drinking water has driven research
into advanced treatment technologies. Among them, non-thermal plasma water treatment
emerges as a promising approach to deactivate microorganisms and ensure water safety. This
study investigated three configurations of non-thermal plasma - Tip-Flat, Flat-Flat, and
Double Tip-Flat - analyzing their distinctive behavior properties. Additionally, it examined
the survival of E. coli colonies after treatment, identifying key system parameters such as
input power, operation time, feed gas, and flow rate. These parameters directly control the
system's performance and effectiveness. The study also explores relevant physicochemical
parameters to assess the quality of water treated by non-thermal plasma, considering
established standards for potability. The Tip-Flat reactor, due to its lower breakdown voltage
in the formation of electrical discharge with argon plasma, demonstrated stability through
intense coloration during operation. From the initial tests, the reactor showed hyperactivity,
regardless of time and voltage, indicating electron particle agitation and triggering increasing
chemical reactions. Its remarkable bubble productivity suggests a higher production of
chemical species in the medium. A new experimental design overcame challenges and
optimized operational conditions. Despite statistical analysis not indicating significance for
gas type and flow rate, specific observations reinforce the superiority of O2 plasma. The
positive trend in treatment time and the highlighted relevance of the "Voltage" variable
minimizes the need for optimization. These results guide future investigations for the effective
application of non-thermal plasma in bacterial inactivation
Agricultura familiar e desenvolvimento territorial em uma região mineradora : o caso dos municípios de Mariana e Ouro Preto.
No full textEffects of a lycopene-layered double hydroxide composite administration in cells and lungs of adult mice.
No full textLycopene is a natural compound with one of the highest antioxidant activities. Its consumption is associated with
lower risks in lung cancer and chronic obstructive pulmonary disease, for example. Experimentally, a murine
model demonstrated the ingestion of lycopene, which reduced the damage in lungs caused by cigarette smoke.
Since lycopene is highly hydrophobic, its formulations in supplements and preparations for laboratory assays are
based on oils, additionally, bioavailavility is low. We developed a lycopene layered double hydroxide (Lyc-LDH)
composite, which is capable of transporting lycopene aqueous media. Our objective was to evaluate the cyto-
toxicity of Lyc-LDH and the intra-cellular production of reactive oxygen species (ROS) in J774A.1 cells. Also, in
vivo assays were conducted with 50 male C57BL/6 mice intranasally treated with Lyc-LDH 10 mg/kg (LG10),
Lyc-LDH 25 mg/kg (LG25) and Lyc-LDH 50 mg/kg (LG50) during five days compared against a vehicle (VG) and
control (CG) group. The blood, bronchoalveolar lavage fluid (BALF) and lung tissue were analyzed. The results
revealed that Lyc-LDH composite attenuated intracellular ROS production stimulated with lipopolysacharide. In
BALF, the highest doses of Lyc-LDH (LG25 and LG50) promoted influx of macrophages, lymphocytes, neutrophils
and eosinophils compared to CG and VG. Also, LG50 increased the levels of IL-6 and IL-13, and promoted the
redox imbalance in the pulmonary tissue. On the contrary, low concentrations did not produce significative
effects. In conclusion, our results suggest that intranasal administration of high concentrations of Lyc-LDH in-
duces inflammation as well as redox status changes in the lungs of healthy mice, however, results with low
concentrations open a promising way to study LDH composites as vehicles for intranasal administration of
antioxidant coadjuvants