Connaissance projet Flashcards
(41 cards)
Le cascudo serait plus resistant. qu’est ce qui fait qu’un animal peut être plus resistant qu’un autre ? comment on le détecte
—ome authors suggest that the liver of herbivorous bottom fish possess an antioxidant defence mechanism that is more efficient than piscivorous fish .
e know that because like since the antioxidant enzymes were less altered in H. commersoni (herbivorus) exposed to DDT and methylmercury (Bussolaro et al., 2010). In this sense, our data indicate that H. intermedius, a piscivorous species, has a greater oxidative stress response than H. affinis,
Quel métaux penses tu qui aura le plus d’effet ?
Et hypostomus affinis, idée de quelle sera l’autre espèce ? Astyanax ?
Pourquoi ne pas prendre la même espèce ?
Hypostomus affinis : preference pour …..ne se retrouve pas aprtout . Plus difficile au rio paraopeba
Dans l’étude weber et al., quelle était la différence de metaux entre P1 et P2 pour l’eau et les sédiments
The metal loads of Fe, Pb, Ni, and As in the water showed no statistical differences between sites, (p > 0.05), but Mn was higher in S2 site (p = 0.001). Regarding sediment, Ni (p = 0.001), Pb (p = 0.001), and As (p = 0.001) were statistically higher in S2, but Fe and Mn showed no significant differences among sites (
Pourquoi prendre différents biomarquers de stress ?
Prendre différents marqueurs comme la SOD, la CAT et le GSH permet d’obtenir une vision globale des réponses du stress oxydatif face aux métaux, car chaque marqueur reflète une étape spécifique de la défense antioxydante. Cela permet de mieux comprendre les mécanismes de détoxification, les déséquilibres cellulaires, et d’identifier les cibles précises des effets toxiques des métaux.—
A quel bassin apartient le rio doce ?
Le rio paraopeba
dans quels bassin se jettent-til ?
Le Rio Doce appartient au bassin hydrographique du Rio Doce, qui est distinct et se jette directement dans l’océan Atlantique.
Le Rio Paraopeba fait partie du bassin hydrographique du Rio São Francisco, puisqu’il est l’un des affluents du Rio São Francisco.
Le Rio Doce se jette dans l’océan Atlantique. Il traverse les états de Minas Gerais et Espírito Santo avant d’atteindre la côte.
Le Rio Paraopeba, quant à lui, est un affluent du Rio São Francisco, l’un des plus grands fleuves du Brésil.—
Penses tu trouve rbeaucoup de fer dans P1 ?
he iron (Fe) levels at both sites were high because this region of the iron quadragle has high levels of iron in the soil
que sont les effets à une haute exposition au Mn ?
anganese, which is an essential metal, was found in high concentrations in waters at Doce River. A study with Oreochromis niloticus showed that fishes exposed to manganese at high concentrations can promote DNA damage and activates oxidative stress in the liver
A quels metals est due la Melattotionein
Fe and Mg, which exhibited similar concentrations between sites, do not appear to induce the expression of metallothionein (Sevcikova et al., 2011). The high levels of hepatic metallothionein in the two species of the present study may be related to the action of several metals acting together, as observed in some rivers polluted by metal
what are heat shock protein
—Heat shock proteins (HSPs) are a family of proteins produced by cells in response to exposure to stressful condition
hsp perform important functions in the folding and unfolding or translocation of proteins, as well as in the assembly and disassembly of protein complexes
que sont les The condition factor (fulton) (K) and Hepato-somatic index (HSI) ?
Pourquoi les utiliser
Condition Factor (K)
Le Condition Factor (K) est une mesure morphométrique qui évalue l’état corporel ou la “santé” générale d’un poisson. Il est calculé à partir de la relation entre le poids du poisson et sa longueur (souvent selon la formule :
Utilité :
Indique l’état nutritionnel ou énergétique du poisson.
Aide à évaluer les effets de facteurs environnementaux (comme la pollution ou la disponibilité de nourriture) sur la condition physique du poisson.
Hepato-somatic Index (HSI)
Le Hepato-somatic Index (HSI) est un ratio entre le poids du foie et le poids total du poisson (
Il reflète l’état métabolique du foie, un organe central pour la détoxification et le métabolisme énergétique.
Utilité :
Évaluer les effets des contaminants environnementaux (comme les métaux lourds) qui impactent le foie—
qu’est ce que le CYP1A et que fait iln
–, CYP1A is an enzyme that plays a role in the biotransformation of environmental toxicants and carcinogens, including heavy metals and is widely used in ecotoxicological field studies
Que sont les concentrations de metaux lourds du Rio dosse maintenant ?
Macêdo et al., : Herein, with water samples collected 32 months after the disaster, we found lower concentrations of Fe, Mn, Cd, and Al when compared with the concentrations of these metals right after the rupture. However, the concentrations of Fe, Cd, and Hg are still higher than those found before the rupture
que répondre si on te dit que les concentrations sont pas si grosses ?
n addition, the environment is being influenced by distinct heavy metal mixtures at each sampling site as evidenced by the PCA analyses. Therefore, exposure of organisms to this complex mixture of chemical contaminants can cause toxic effects even if these individual contaminants are present at low concentrations
Mixtures of toxic elements such as Hg, Pb, Cd, or metal-associated toxicants, such as methylmercury, tributyltin, and alkali may occur in polluted aquatic environments and may be expected to cause combined toxicity
Moreover, studies have shown that the combination of heavy metals has an effect on the bioaccumulation of these pollutants in fish organ
que signifie un detachment of the epithelium
The observed detachment of the epithelium has been described as a defense mechanism that leads to a decreased toxicant entry through the gills by the increasing the distance between the toxicant and blood in the primary and secondary lamellae
que sont les MRC ? que sont leurs rôles dans les branchies
Mitochondria Rich Cell
MRCs are large round cells typically distributed on the posterior edge of the primary lamellar epithelium and in the interlamellar mass in teleost gills (Macirella and Brunelli, 2017). They facilitate the transport of ions through the gill epithelium
n increase in number (P4 group), disorganization and hypertrophy (P2 and P3 groups) of MRC and NKA, as observed through immunolabeling, may be associated with a protective mechanism against pollution that is caused mainly by heavy metals, which may involve physiological and morphological adjustments to maintain optimum ion uptake
the distribution and increase in the number of MRCs in fish gills can be considered as an adaptive response against the exposure to heavy metals in their habitat, which was triggered by the body’s attempt to correct the ionic imbalance brought about by pollution.
Cite des metaux qui se sont montrés toxiques pour les branchies
Cu, Cd, Fe, and Ni
Que penses tu que sera l’impact du methyl mercury ?
On étudie des cas de mines de fer et une étude de notre laboratoire ne voyait pas de différence entre les sites contminité ou non de mercure, et montrait des concentrations basses.
Cependant, les sites sont pas très loin d’une mine d’or, donc des pollultions entre l’étude de notre labo et maintenant sont possibles, mais ce serait pas due à la mine
y, mainly iron ore (Timbopeba, Germano and Alegria mines), and in addition, it is also full of manganese and gold, which follows that there is evident predatory exploration activities (prospectors)
Que sont les causes de la rupture du barrage de rio doce et brumardinho
Barragem de Mariana (Fundão)
O colapso ocorreu devido a problemas estruturais, incluindo o uso de encostas muito íngremes no projeto e o sobrecarregamento dos rejeitos (resíduos da mineração). Além disso, a manutenção e o monitoramento eram insuficientes. Investigadores identificaram que a Samarco (uma parceria entre a Vale e a BHP) foi negligente em abordar problemas conhecidos de estabilidade da barragem
LE MONDE.FR
FRANCE 24 WEBDOCUMENTARIES
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Barragem de Brumadinho
O rompimento foi causado pela liquefação dos rejeitos, um processo em que os resíduos sólidos perdem a rigidez e se comportam como líquidos, comprometendo a estrutura. Relatórios indicam que a Vale ignorou alertas de segurança emitidos por auditores internos e externos, priorizando lucros em detrimento da mitigação de riscos
MULTINATIONALS OBSERVATORY
SCIELO
Pas clair Several aspects have been evocated including foundation failure or bad impoundment management, fast increase of tailing deposition, poor management, and human inadequate practices.
n 2008, the Fundão dam had presented several anomalies related to drainage construction defects, upwellings, mud and water management errors and” (do Carmo et al., 2017) As the dam embankment continued, surface upwellings began to appear at the retreat of the left shoulder at various elevations and on various occasions during 2013. The saturated mass with sandy tailings was growing, and in August 2014, the drainage carpet controlling this saturation reached its maximum capacity. Meanwhile, the mud under the landfill was responding to the increase in the load that was being deposited by the embankment. The way in which it responded, and the consequent effect on the sands, was what finally made the sands liquefy.” (Carmoe t al., 2017)
quelles sont le type de pollution qu’on retrouve au rio paraopeba
Até o ano de 2011, os principais responsáveis pela degradação das águas eram os lançamentos de esgotos domésticos e industriais, além do uso e ocupação inadequados do solo nas áreas urbana e rural, notadamente no que diz respeito à ausência ou insuficiência de cobertura vegetal
comment la caspase 3 declenche l’apoptose
Caspase-3 cleaves structural and regulatory proteins, which causes cellular shrinkage, DNA fragmentation, and membrane blebbing.
que sont les genes de eregulation de L’apoptose ? de la necrose ?
Necroptosis is regulated by LEF1, RIP1, and RIP3, and finally
apoptosis regulation are caspases, TP53, FAS, BCL-2
