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1.
Environ Geochem Health ; 45(11): 8257-8269, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37580456

RESUMO

It has been reported that volcanoes release several tonnes of mercury per year among other heavy metals through eruptions, fumaroles, or diffuse soil degassing. Since a high percentage of the world's population lives in the vicinity of an active volcano, the aim of this study is to evaluate the accumulation of these metals in the central nervous system and the presence of cellular mechanisms of heavy metal detoxification such as metallothioneins. To carry out this study, wild mice (Mus musculus) chronically exposed to an active volcanic environment were captured in Furnas village (Azores, Portugal) and compared with those trapped in a reference area (Rabo de Peixe, Azores, Portugal). On the one hand, the heavy metal load has been evaluated by analyzing brain and cerebellum using ICP-MS and a mercury analyzer and on the other hand, the presence of metallothionein 2A has been studied by immunofluorescence assays. Our results show a higher load of metals such as mercury, cadmium and lead in the central nervous system of exposed mice compared to non-exposed individuals and, in addition, a higher immunoreactivity for metallothionein 2A in different areas of the cerebrum and cerebellum indicating a possible neuroprotection process.


Assuntos
Mercúrio , Metais Pesados , Animais , Camundongos , Metalotioneína , Neuroproteção , Metais , Mercúrio/toxicidade , Sistema Nervoso Central , Metais Pesados/toxicidade
2.
Food Chem ; 410: 135319, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36634564

RESUMO

The tomato processing industry is one of the world's most important markets. This industry aims to optimise production, minimise energy costs and waste streams while ensuring high-quality products. This sector produces substantial amounts of by-products frequently disposed of as waste rather than reintroducing them with a new intent into the supply chain. However, these by-products are rich in bioactive compounds (BC), including carotenoids, fibre, which exhibit antioxidant, anti-inflammatory and chemopreventive properties, and cardiovascular protection. Reusing these compounds is favourable to reducing the environmental impact and enables the development of added-value products with various possible uses such as food and feed additives, nutraceuticals, cosmeceuticals, etc. This review summarises relevant issues towards the recovery and valorisation of BC from industrial tomato by-products within a circular economy context.


Assuntos
Solanum lycopersicum , Humanos , Carotenoides/análise , Antioxidantes , Manipulação de Alimentos , Suplementos Nutricionais
3.
Environ Res ; 209: 112868, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35143803

RESUMO

A fruit processing wastewater was submitted to different advanced oxidation processes, namely, electro-Fenton (EF), electrochemical oxidation (EO), activated persulfate (PS), and combined EF/PS. The performance of the treatment processes, at different experimental conditions, regarding organic load removal, biodegradability increment, toxicity reduction, and specific energy consumption (Esp), was evaluated. At the experimental conditions studied, EO led to the treated solutions with the highest biodegradability increment, from 0.24 to 0.48, and toxicity reduction towards Daphnia magna, from 5.8 to 1.5 toxic units, without requiring the addition of chemicals. Nevertheless, the highest chemical oxygen demand (COD) removals were obtained for EF and combined EF/PS treatments. For the electrochemical processes, an increase in COD removal rate with applied current density (j) was observed. However, the increase in j substantially raised the Esp. In PS treatment, COD removals above 80% were only achieved for high amounts of added persulfate and iron, which led to less biodegradable and more toxic solutions. Combined EF/PS attained the lowest Esp values, mainly due to the conductivity increase originated by the persulfate and iron salts addition. Besides the disadvantage of the chemicals added, this combined treatment led to treated solutions with very acidic pH and significant iron content.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Análise da Demanda Biológica de Oxigênio , Frutas/química , Peróxido de Hidrogênio , Oxirredução , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Águas Residuárias/toxicidade , Poluentes Químicos da Água/análise
4.
Environ Geochem Health ; 44(8): 2783-2797, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34448062

RESUMO

Air pollutants (either of natural or anthropogenic origin) represent a considerable environmental risk to human health by affecting the respiratory system and causing respiratory disorders. In this study, we investigate the effects of chronic exposure to hydrothermal emissions on the nasal cavity of mice since it is the first and the most exposed region of the respiratory system. This study, carried in S. Miguel Island, Azores-Portugal, used Mus musculus as a bioindicator species. Mice were captured in an area with non-eruptive active volcanism (Furnas Village) and another area without volcanism (Rabo de Peixe, reference site). The hydrothermal emissions present at Furnas Village are characterized by the continuous release of several gases (CO2, H2S, 222Rn) along with metals (e.g. Hg, Cd, Zn, Al) and particulate matter into the environment. We test the hypothesis whether chronic exposure to this specific type of pollution causes epithelial morphometric, mucosecretory and neuronal alterations on the nasal cavity. Thickness measurements were taken in the squamous, respiratory and olfactory epithelia. The relative density of cell types (basal, support and neurons) was also assessed in the olfactory epithelium and the mucosecretory activity was determined in the lateral nasal glands, Bowman's gland and goblet cells. Mice chronically exposed to hydrothermal emissions presented thinner olfactory epithelia and lesser mucous production, which could result in loss of olfactory capabilities as well as a decrease in the protective function provided by the mucous to the lower respiratory tract. For the first time, it is demonstrated that, in mice, this specific type of non-eruptive active volcanism causes epithelial and mucosecretory alterations, leading to the loss of olfactory capabilities.


Assuntos
Poluentes Atmosféricos , Cavidade Nasal , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Animais , Gases , Metais , Camundongos , Cavidade Nasal/química , Material Particulado
5.
Biol Trace Elem Res ; 200(6): 2838-2847, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34415497

RESUMO

Mercury accumulation has been proposed as a toxic factor that causes neurodegenerative diseases. However, the hazardous health effects of gaseous elemental mercury exposure on the spinal cord in volcanic areas have not been reported previously in the literature. To evaluate the presence of volcanogenic inorganic mercury in the spinal cord, a study was carried out in São Miguel island (Azores, Portugal) by comparing the spinal cord of mice exposed chronically to an active volcanic environment (Furnas village) with individuals not exposed (Rabo de Peixe village), through the autometallographic silver enhancement histochemical method. Moreover, a morphometric and quantification analysis of the axons was carried out. Results exhibited mercury deposits at the lumbar level of the spinal cord in the specimens captured at the site with volcanic activity (Furnas village). A decrease in axon calibre and axonal atrophy was also observed in these specimens. Given that these are relevant hallmarks in the neurodegenerative pathologies, our results highlight the importance of the surveillance of the health of populations chronically exposed to active volcanic environments.


Assuntos
Mercúrio , Animais , Açores , Mercúrio/toxicidade , Camundongos , Portugal , Medula Espinal , Erupções Vulcânicas
6.
Mediators Inflamm ; 2021: 5891095, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34671225

RESUMO

Neuroinflammation is a process related to the onset of neurodegenerative diseases; one of the hallmarks of this process is microglial reactivation and the secretion by these cells of proinflammatory cytokines such as TNFα. Numerous studies report the relationship between neuroinflammatory processes and exposure to anthropogenic air pollutants, but few refer to natural pollutants. Volcanoes are highly inhabited natural sources of environmental pollution that induce changes in the nervous system, such as reactive astrogliosis or the blood-brain barrier breakdown in exposed individuals; however, no neuroinflammatory event has been yet defined. To this purpose, we studied resting microglia, reactive microglia, and TNFα production in the brains of mice chronically exposed to an active volcanic environment on the island of São Miguel (Azores, Portugal). For the first time, we demonstrate a proliferation of microglial cells and an increase in reactive microglia, as well an increase in TNFα secretion, in the central nervous system of individuals exposed to volcanogenic pollutants.


Assuntos
Poluentes Atmosféricos/toxicidade , Hipocampo/patologia , Doenças Neuroinflamatórias/etiologia , Animais , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Proteínas de Ligação ao Cálcio/análise , Hipocampo/imunologia , Camundongos , Proteínas dos Microfilamentos/análise , Microglia/patologia , Fator de Necrose Tumoral alfa/biossíntese , Erupções Vulcânicas
7.
Environ Geochem Health ; 43(11): 4863-4867, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33860889

RESUMO

Volcanoes are a natural source of gaseous elemental mercury (GEM) (Hg0). Monitoring GEM releases of volcanic origin has been widely studied; however, few studies have been performed about the biomonitoring of species exposed to GEM, rendering an unknown risk to the worldwide populations living in the vicinity of an active volcano. In this pilot study, we used Mus musculus as a bioindicator species to understand to what extent lungs are the main route of mercury uptake in populations chronically exposed to active volcanic environments. Autometallographic silver protocol was used to detect mercury deposits in the histological lung slides. Abundant mercury deposits were found in the lungs of specimens captured at the site with volcanic activity (Furnas Village, S. Miguel Island-Azores). The presence of mercury in the lungs could represent not only hazardous effects to the lung itself but also to other tissues and organs, such as brain and kidneys. This study confirms that the main uptake route for GEM is the lungs and that, even at very low concentrations in the environment, a chronic exposure to Hg0 results in its bioaccumulation in the lung tissue. These results reinforce that biomonitoring studies should be combined with monitoring classical approaches in order to better characterize the risks of exposure to Hg0 in volcanic environments.


Assuntos
Poluentes Atmosféricos , Mercúrio , Poluentes Atmosféricos/análise , Animais , Açores , Monitoramento Ambiental , Pulmão/química , Mercúrio/análise , Mercúrio/toxicidade , Camundongos , Projetos Piloto , Erupções Vulcânicas
8.
Vet Parasitol Reg Stud Reports ; 23: 100511, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33678366

RESUMO

Klossiella is a genus of apicomplexan coccidian parasites with a global distribution, whose members typically infect the renal tissue of a wide variety of vertebrate hosts with a high level of host specificity. The presence of this parasite has been previously associated with kidney inflammatory processes. To our knowledge, this is the first report on the prevalence of Klossiella muris in the house mouse (Mus musculus) in Portugal (São Miguel Island - Azores). The prevalence of K. muris was determined through histopathological examination of renal tissue collected during necropsy of 130 mice captured between the years of 2011-2019. K. muris was diagnosed in 45.38% (CI95: 40.9-85.4) of the examined mice. Infection with this parasite was associated with mild to severe kidney inflammation, assessed by the presence of inflammatory processes in the renal cortex and medulla. CAPSULE: First record on coccidiosis caused by infection of Klossiella muris in Mus musculus in Portugal.


Assuntos
Coccidiose , Eucoccidiida , Camundongos/parasitologia , Doenças dos Roedores , Animais , Açores , Coccidiose/epidemiologia , Coccidiose/veterinária , Portugal/epidemiologia , Prevalência , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/parasitologia
9.
Environ Geochem Health ; 43(1): 171-183, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32794111

RESUMO

The health effects of mercury vapor exposure on the brain in volcanic areas have not been previously addressed in the literature. However, 10% of the worldwide population inhabits in the vicinity of an active volcano, which are natural sources of elemental mercury emission. To evaluate the presence of mercury compounds in the brain after chronic exposure to volcanogenic mercury vapor, a histochemical study, using autometallographic silver, was carried out to compare the brain of mice chronically exposed to an active volcanic environment (Furnas village, Azores, Portugal) with those not exposed (Rabo de Peixe village, Azores, Portugal). Results demonstrated several mercury deposits in blood vessels, white matter and some cells of the hippocampus in the brain of chronically exposed mice. Our results highlight that chronic exposure to an active volcanic environment results in brain mercury accumulation, raising an alert regarding potential human health risks. These findings support the hypothesis that mercury exposure can be a risk factor in causing neurodegenerative diseases in the inhabitants of volcanically active areas.


Assuntos
Química Encefálica , Exposição Ambiental , Poluentes Ambientais/metabolismo , Mercúrio/metabolismo , Camundongos/metabolismo , Erupções Vulcânicas/efeitos adversos , Animais , Animais Selvagens/metabolismo , Açores , Química Encefálica/efeitos dos fármacos , Feminino , Gases/efeitos adversos , Histocitoquímica/veterinária , Masculino , Fatores de Risco
10.
J Toxicol Environ Health A ; 84(5): 213-226, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33283687

RESUMO

Air pollution has been associated with neuroinflammatory processes and is considered a risk factor for the development of neurodegenerative diseases. Volcanic environments are considered a natural source of air pollution. However, the effects of natural source air pollution on the central nervous system (CNS) have not been reported, despite the fact that up to 10% of the world's population lives near a historically active volcano. In order to assess the response of the CNS to such exposure, our study was conducted in the island of Sao Miguel (Azores, Portugal) in two different areas: Furnas, which is volcanically active one, and compared to Rabo de Peixe, a reference site without manifestations of active volcanism using Mus musculus as a bioindicator species. To evaluate the state of the astroglial population in the dentate gyrus in both samples, the number of astrocytes was determined using immunofluorescence methods (anti-GFAP and anti-GS). In addition, the astrocytic branches in that hippocampal area were examined. Our results showed an increase in GFAP+ astrocytes and a reduction in GS+ astrocytes in Furnas-exposed mice compared to animals from Rabo de Peixe. In addition, astrocytes in the dentate gyrus of chronically exposed animals exhibited longer branches compared to those residing at the reference site. Thus, reactive astrogliosis and astrocyte dysfunction are found in mice living in an active volcanic environment.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Giro Denteado/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Gliose/patologia , Doenças dos Roedores/patologia , Erupções Vulcânicas/efeitos adversos , Animais , Animais Selvagens , Açores , Giro Denteado/patologia , Gliose/induzido quimicamente , Camundongos , Doenças dos Roedores/induzido quimicamente
11.
Arq. bras. med. vet. zootec. (Online) ; 72(6): 2053-2058, Nov.-Dec. 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1142284

RESUMO

Objetivou-se avaliar um programa de controle da artrite encefalite caprina (AEC), por meio de testes diagnósticos sensíveis, separação de mãe e cria após o parto e medidas de manejo, com o intuito de formar rebanho livre do vírus. Utilizou-se um total de 47 cabritos da raça Saanen, mantidos isoladamente até o resultado dos primeiros testes de reação em cadeia de polimerase nested (PCR nested) e Western Blotting (WB), com base na coleta de sangue no momento do nascimento (M0). No PCR nested, quatro animais foram positivos, no M0, e foram eutanasiados. Posteriormente, os demais 43 cabritos foram submetidos à coleta de sangue aos 60 (M60) e 270 (M270) dias de vida para realização de novos testes de WB e PCR nested, que não detectaram animais positivos. Pode-se afirmar que a metodologia adotada neste estudo foi efetiva no controle da doença, nas fases de aleitamento e pós-aleitamento, e que a combinação do sistema de manejo, a fim de propiciar diminuição de risco de transmissão horizontal, com técnicas de diagnóstico mais apuradas, como o WB e a PCR nested, é relevante para elaboração de plano estratégico de controle da enfermidade.(AU)


We aimed to evaluate a program to control Caprine Arthritis Encephalitis (CAE), using diagnostic tests, separation of the mother and postpartum and other management measures, in order to form a free flock of the virus. We used a total of 47 Saanengoats in isolation until the results of the first nested Polymerase Chain Reaction (nested PCR) and Western Blotting (WB) tests, based on blood collection at the time of birth (M0). In the nested PCR, 4 animals were positive, at M0, and were eliminated. Later, the other 43goats were submitted to blood collection at 60 (M60) and 270 (M270) days of life to perform new tests of WB and nested PCR, which did not detect positive animals. We can affirm that the methodology adopted in this study was effective in the control of the disease, in the phase of breastfeeding and post-breastfeeding, and that the combination of the management system, which allows a reduction of risk of horizontal transmission, with more accurate diagnostic techniques, such as WB and nested PCR, is relevant for the elaboration of a strategic plan for the disease control.(AU)


Assuntos
Animais , Cabras/virologia , Infecções por Lentivirus/prevenção & controle , Vírus da Artrite-Encefalite Caprina/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária
12.
Artigo em Inglês | MEDLINE | ID: mdl-31585631

RESUMO

In contributing to this Special Issue of Mutation Research dedicated to Professor Bruce N. Ames in recognition of his 90th birthday in December 2018, we intend to portray the importance not only of the Ames Salmonella/mammalian-microsome mutagenicity assay in some of our studies over the years, but also the importance of the insight that Bruce Ames brought to the field of genetic toxicology.


Assuntos
Testes de Mutagenicidade , Salmonella/efeitos dos fármacos , Ativação Metabólica , Poluentes Ocupacionais do Ar/toxicidade , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Flavonoides/química , Flavonoides/toxicidade , Engenharia Genética , Humanos , Microssomos Hepáticos/enzimologia , Estrutura Molecular , Testes de Mutagenicidade/métodos , Mutagênicos/toxicidade , Nevirapina/química , Nevirapina/toxicidade , Exposição Ocupacional , Quercetina/toxicidade , Ratos , Salmonella/genética , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Especificidade da Espécie , Toxicologia/métodos , Urina/química
13.
Environ Pollut ; 253: 864-871, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349195

RESUMO

It is estimated that 10% of the worldwide population lives in the vicinity of an active volcano. However, volcanogenic air pollution studies are still outnumbered when compared with anthropogenic air pollution studies, representing an unknown risk to human populations inhabiting volcanic areas worldwide. This study was carried out in the Azorean archipelago of Portugal, in areas with active non-eruptive volcanism. The hydrothermal emissions within the volcanic complex of Furnas (São Miguel Island) are responsible for the emission of nearly 1000 tons of CO2 per day, along with H2S, the radioactive gas - radon, among others. Besides the gaseous emissions, metals (e.g., Hg, Cd, Al, Ni) and particulate matter are also released into the environment. We test the hypothesis that chronic exposure to volcanogenic air pollution alters the histomorphology of the bronchioles and terminal bronchioles, using the house mouse, Mus musculus, as bioindicator species. Mus musculus were live-captured at three different locations: two villages with active volcanism and a village without any type of volcanic activity (reference site). The histomorphology of the bronchioles (diameter, epithelium thickness, smooth muscle layer thickness, submucosa thickness and the histological evaluation of the peribronchiolar inflammation) and of the terminal bronchioles (epithelium thickness and classification) were evaluated. Mice chronically exposed to volcanogenic air pollution presented bronchioles with increased epithelial thickness, increased smooth muscle layer, increased submucosa thickness and increased peribronchiolar inflammation. Similarly, terminal bronchioles presented structural alterations consistent with bronchodysplasia. For the first time we demonstrate that chronic exposure to non-eruptive volcanically active environments causes inflammation and histomorphological alterations in mice lower airways consistent with asthma and chronic bronchitis. These results reveal that chronic exposure to non-eruptive volcanic activity represents a risk factor that can affect the health of the respiratory system of humans inhabiting hydrothermal areas.


Assuntos
Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Testes de Toxicidade Crônica , Erupções Vulcânicas , Poluentes Atmosféricos/análise , Animais , Asma , Bronquíolos/patologia , Gases , Humanos , Inflamação , Metais , Camundongos , Material Particulado , Portugal
14.
Phys Rev E ; 99(2-1): 022201, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30934216

RESUMO

In the present work we explore a prestretched oscillator chain where the nodes interact via a pairwise Lennard-Jones potential. In addition to a homogeneous solution, we identify solutions with one or more (so-called) "breaks," i.e., jumps. As a function of the canonical parameter of the system, namely, the precompression strain d, we find that the most fundamental one-break solution changes stability when the monotonicity of the Hamiltonian changes with d. We provide a proof for this (motivated by numerical computations) observation. This critical point separates stable and unstable segments of the one-break branch of solutions. We find similar branches for two- through five-break branches of solutions. Each of these higher "excited state" solutions possesses an additional unstable pair of eigenvalues. We thus conjecture that k-break solutions will possess at least k-1 (and at most k) pairs of unstable eigenvalues. Our stability analysis is corroborated by direct numerical computations of the evolutionary dynamics.

15.
Chemosphere ; 222: 227-234, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30708156

RESUMO

Volcanogenic air pollution studies and their effects on the respiratory system are still outnumbered by studies regarding the effects of anthropogenic air pollution, representing an unknown risk to human population inhabiting volcanic areas worldwide (either eruptive or non-eruptive areas). This study was carried in the archipelago of the Azores- Portugal, in two areas with active volcanism (Village of Furnas and Village of Ribeira Quente) and a reference site (Rabo de Peixe). The hydrothermal volcanism of Furnas volcanic complex is responsible for the release of 1000 t d-1 of CO2, H2S, the radioactive gas - radon, among others. Besides the gaseous emissions, particulate matter and metals (Hg, Cd, Zn, Al, Ni, etc.) are also released into the environment. We tested a hypothesis whether chronic exposure to volcanogenic air pollution causes lung structural remodelling, in the house mouse, Mus musculus, as a bioindicator species. Histopathological evaluations were performed to assess the amount of macrophages, mononuclear leukocyte infiltrate, pulmonary emphysema, and the production of pro-inflammatory cytokine TNF-α. Also, the percentage of collagen and elastin fibers was calculated. Mice chronically exposed to volcanogenic air pollution presented an increased score in the histopathological evaluations for the amount of macrophages, mononuclear leukocyte infiltrate, pulmonary emphysema and production of TNF-α; and also increased percentages of collagen and elastin. For the first time, we demonstrate that non-eruptive active volcanism has a high potential to cause lung structural remodelling. This study also highlights the Mus musculus as a useful bioindicator for future biomonitoring programs in these type of volcanic environments.


Assuntos
Poluição do Ar/efeitos adversos , Remodelação das Vias Aéreas , Fator de Necrose Tumoral alfa/biossíntese , Erupções Vulcânicas/efeitos adversos , Animais , Açores , Gases/química , Humanos , Exposição por Inalação/efeitos adversos , Pulmão/patologia , Macrófagos , Metais , Camundongos , Material Particulado/efeitos adversos , Material Particulado/química , Portugal
16.
Phys Rev E ; 98(2-1): 022205, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30253492

RESUMO

We study a two-dimensional incoherently pumped exciton-polariton condensate described by an open-dissipative Gross-Pitaevskii equation for the polariton dynamics coupled to a rate equation for the exciton density. Adopting a hydrodynamic approach, we use multiscale expansion methods to derive several models appearing in the context of shallow water waves with viscosity. In particular, we derive a Boussinesq/Benney-Luke-type equation and its far-field expansion in terms of Kadomtsev-Petviashvili-I (KP-I) equations for right- and left-going waves. From the KP-I model, we predict the existence of vorticity-free, weakly (algebraically) localized two-dimensional dark-lump solitons. We find that, in the presence of dissipation, dark lumps exhibit a lifetime three times larger than that of planar dark solitons. Direct numerical simulations show that dark lumps do exist, and their dissipative dynamics is well captured by our analytical approximation. It is also shown that lumplike and vortexlike structures can spontaneously be formed as a result of the transverse "snaking" instability of dark soliton stripes.

17.
Mar Biol ; 165(10): 152, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30220735

RESUMO

Many predictive models of spatial and temporal distribution (e.g. in response to climate change or species introductions) assume that species have one environmental niche that applies to all individuals. However, there is growing evidence that individuals can have environmental preferences that are narrower than the species niche. Such individual specialization has mainly been studied in terms of dietary niches, but a recent increase in the availability of individual movement data opens the possibility of extending these analyses to specialisation in environmental preferences. Yet, no study to date on individual specialisation has considered the environmental niche in its multidimensionality. Here we propose a new method for quantifying individual specialisation in multiple dimensions simultaneously. We compare the hypervolumes in n-dimensional environmental niche space of each individual against that of the population, testing for significant differences against a null model. The same method can be applied to a 2-dimensional geographic space to test for site fidelity. We applied this method to test for individual environmental specialisation (across three dimensions: sea surface temperature, eddy kinetic energy, depth) and for site fidelity among satellite-tracked black-browed albatrosses (Thalassarche melanophris) and grey-headed albatrosses (Thalassarche chrysostoma), during chick-rearing at South Georgia. We found evidence for site fidelity in both species and of environmental specialisation among individual grey-headed but not black-browed albatrosses. Specialisation can affect the resilience of populations affected by natural and anthropogenic changes in the environment, and hence has implications for population dynamics and conservation.

18.
Sci Total Environ ; 636: 1553-1564, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29913616

RESUMO

Abamectin (ABA) toxicity in fish, amphibian and mammals was already proven, but its effect on birds is almost unknown. Thus, the aim of our study is to assess the impact of exposure to water with ABA for 40 days at predicted environmentally relevant concentrations on the behavior of female Japanese quails (Coturnix coturnix japonica). The three following experimental groups (n = 10 each) were set: "control", quails exposed to drinking water, without ABA, "EC1x" and "EC1000x" (0.31 mg a.i./L and 310.0 a.i./L, respectively; via commercial formulation Kraft® 36EC). The open field test showed anxiolytic response in birds exposed to ABA. These birds did not show locomotor changes or aggressive behavior in the aggressiveness test. Quails exposed to the pesticide did not react to the introduction of an object in the experimental box during the object recognition test, and it suggested perception deficit due to ABA. Moreover, these birds did not recognize the cat (Felix catus) and the vocalization of a hawk (Rupornis magnirostris) as potential predatory threats. These responses also suggest anti-predatory behavior deficit due to the pesticide. Thus, our study is pioneer in showing that water with ABA, at tested concentrations, influences the behavior of C. coturnix japonica, as well as in highlighting the potential impacts of this pesticide on this group of birds.


Assuntos
Comportamento Animal/efeitos dos fármacos , Coturnix/fisiologia , Ivermectina/análogos & derivados , Praguicidas/toxicidade , Animais , Gatos , Feminino , Ivermectina/toxicidade
19.
Chemosphere ; 205: 433-442, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29705634

RESUMO

The electrodegradation of the 4-aminonaphthalene-1-sulfonic acid (4AN1S), 5-aminonaphthalene-2-sulfonic acid (5AN2S) and 8-aminonaphthalene-2-sulfonic acid (8AN2S) was studied, using two electrode materials as anode, BDD and Ti/Pt/PbO2, and two different electrolytes, sodium sulfate and sodium chloride. The highest COD removal rates were obtained at BDD: for 5AN2S and 8AN2S results were similar in both electrolytes; for 4AN1S, results were better in sodium chloride. The lowest COD removal rates were obtained at the system Ti/Pt/PbO2-sodium sulfate, for all the studied amines. The dissolved organic carbon (DOC) removal was much higher at BDD for all the amines, in sulfate for 5AN2S and 8AN2S and in chloride for 4AN1S. Nitrogen removal was always almost irrelevant in sulfate medium but higher than 60%, after 6-h assays, in chloride. The highest combustion efficiencies were attained at the system BDD-sodium sulfate and were: 4AN1S-75%; 5AN2S-84%; 8AN2S-74%. HPLC results show that total degradation of the studied aminonaphthalene sulfonates is attained at both anode materials, utilizing any of the electrolytes, with a first order kinetics. However, kinetic constants obtained with the variation of the amines concentration in time are 10-40 times higher in chloride, being slightly higher at Ti/Pt/PbO2 than at BDD. Regarding the presence of carboxylic acids during the degradation assays, it was observed that the electrolysis of the amines 5AN2S and 8AN2S always lead to higher amounts of oxalic acid and lower quantities of acetic acid than the electrolysis of the amine 4AN1S.


Assuntos
Aminas/química , Eletrólise/métodos , Naftalenos/química , Eletrodos , Cinética , Nitrogênio , Oxirredução , Sulfatos , Ácidos Sulfônicos/química , Titânio , Poluentes Químicos da Água/química
20.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 139-146, Jan.-Feb. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-888074

RESUMO

O objetivo deste trabalho foi avaliar a utilização periódica de testes de diagnóstico mais sensíveis aliados às práticas de manejo, visando ao controle eficaz da artrite encefalite caprina (CAE). Foram realizadas oito coletas de sangue em matrizes e reprodutores. Da primeira à sétima análise, as coletas foram quadrimestrais, utilizando-se os testes de imunodifusão em gel de agarose (IDGA), ensaio imunoenzimático indireto (ELISA-i) e Western Blot (WB). A oitava coleta aconteceu seis meses após a sétima, utilizando-se o WB e a reação em cadeia de polimerase (PCR). A prevalência da CAE foi de 6,8%, 14,9% e 39,2% no IDGA, ELISA-i e WB, respectivamente. Na última análise, foram detectados 0,9% de animais positivos pelo WB e 10,8% pela PCR. Apesar de não erradicarem a CAE, as medidas adotadas, aliadas à utilização periódica dos testes sorológicos e à combinação com a PCR, foram importantes para reduzir significativamente os animais soropositivos no rebanho.(AU)


The aim of this study was to evaluate the periodic use of more sensitive diagnostic tests associated to management practices for the effective control of caprine arthritis-encephalitis (CAE). We carried out eight blood samples in does and bucks. From the first to the seventh analysis, the samples were quarterly, using Agarose Gel Immunodiffusion (AGID), Enzyme linked immunosorbent assay (i-ELISA) and Western Blot (WB) tests. The eighth collection was made six months after the seventh, using the WB and Polymerase Chain Reaction (PCR). The prevalence of CAE was 6.8%, 14.9% and 39.2% in the AGID, i-ELISA and WB respectively. The last analysis detected 0.9% of animals positive by WB and 10.8% by PCR. Although they do not eradicate CAE, steps taken together with the periodic use of serological tests and the combination with PCR were important to significantly reduce positive animals in the herd.(AU)


Assuntos
Animais , Artrite/diagnóstico , Ruminantes/anormalidades , Planejamento Estratégico , Ensaio de Imunoadsorção Enzimática
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