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1.
Phys Chem Chem Phys ; 26(15): 12188-12198, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591269

RESUMO

Density functional theory (DFT) calculations and an atomistic thermodynamic approach were used to study the geometric rearrangement of sulfur atoms on the Ni- and Cu-doped MoS2 S-edge upon hydrogen adsorption. Under HDS conditions, thermodynamically stable hydrogenated structures were identified as SH groups on the undoped S-edge with 100% sulfur coverage, on the Ni-doped S-edge with 50% sulfur coverage and on the Cu-doped S-edge with 25% sulfur coverage. It was found that the rearrangement of the S atoms is essential to reach the most stable state at the edge for the undoped and Ni-doped S-edge. Hydrogen adsorption on the Ni-doped S-edge leads to the greatest amount of S rearrangement (ΔERearrang = 0.93 eV/H2). Our results suggest that under the reaction conditions, the H2 dissociative adsorption process is strongly coupled to the rearrangement of the sulfur atoms. By examining the differential hydrogen adsorption energy on the most stable edge structures, we found a plausible explanation for the trend in the hydrogenation activity of the doped edges. Our results suggest that Ni enhances the hydrogenation activity of the S-edge by decreasing the S-H bond strength, while Cu poisons it by increasing the S-H bond strength.

2.
Ecotoxicology ; 33(4-5): 457-469, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38097853

RESUMO

Mercury (Hg) endangers human and wildlife health globally, primarily due to its release from artisanal small-scale gold mining (ASGM). During gold extraction, Hg is emitted into the environment and converted to highly toxic methylmercury by microorganisms. In Madre de Dios (MDD), Peru, ASGM dominates the economy and has transformed rainforests into expansive deforested areas punctuated by abandoned mining ponds. The aim of this study was to evaluate the use of bats as bioindicators for mercury pollution intensity in tropical terrestrial ecosystems impacted by ASGM. We collected 290 bat fur samples from three post-ASGM sites and one control site in Madre de Dios. Our results showed a wide Hg distribution in bats (0.001 to 117.71 mg/kg) strongly influenced by feeding habits. Insectivorous and piscivorous bats from ASGM sites presented elevated levels of Hg surpassing the mercury small mammal threshold for small mammals (10 mg/kg). We observed the highest reported fur mercury concentrations for insectivorous Neotropical bats reported to date (Rhynchonycteris naso, 117 mg/kg). Our findings further confirm that Hg emissions from ASGM are entering local food webs and exposing wildlife species at several trophic levels to higher levels of Hg than in areas not impacted by mining. We also found that three bat genera consistently showed increased Hg levels in ASGM sites relative to controls indicating potential usefulness as bioindicators of mercury loading in terrestrial ecosystems impacted by artisanal and small-scale gold mining.


Assuntos
Bioacumulação , Quirópteros , Ecossistema , Monitoramento Ambiental , Ouro , Mercúrio , Mineração , Animais , Quirópteros/metabolismo , Peru , Mercúrio/análise , Mercúrio/metabolismo , Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Poluentes Ambientais/análise
3.
Ecol Appl ; 31(5): e02335, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33780592

RESUMO

Innovative techniques, such as environmental DNA (eDNA) metabarcoding, are now promoting broader biodiversity monitoring at unprecedented scales, because of the reduction in time, presumably lower cost, and methodological efficiency. Our goal was to assess the efficiency of established inventory techniques (live-trapping grids, pitfall traps, camera trapping, mist netting) as well as eDNA for detecting Amazonian mammals. For terrestrial small mammals, we used 32 live-trapping grids based on Sherman and Tomahawk traps (total effort of 10,368 trap-nights); in addition to 16 pitfall traps (1,408 trap-nights). For bats, we used mist nets at 8 sites (4,800 net hours). For medium and large mammals, we used 72 camera trap stations (5,208 camera-days). We identified vertebrate and mammal taxa based on eDNA analysis (12S region, with V05 and Mamm01 markers) from water samples, including a total of 11 3-km transects for stagnant water sampling and seven small streams for running water sampling. A total of 106 mammal species were recorded. Building on sample-based rarefaction and extrapolation curves, both trapping grids and pitfall were successful, recording 91.16% and 82.1% of the expected species for these techniques (~22 and ~9 species), and 16.98% and 6.60% of the total recorded mammal species, respectively. Mist nets recorded 83.2% of the expected bat species (~48), and 34.91% of the total recorded species. Camera trapping recorded 99.2% of the predicted large- and medium-sized species (~31), and 33.02% of the total recorded species. eDNA recorded 75.4% of the expected mammal species for this technique (~68), and 47.0% of the total recorded species. eDNA resulted in a useful tool that saves on effort and reduces sampling costs. This study is among the first to show the large potential of eDNA metabarcoding for assessing Amazonian mammal communities, providing, in combination with conventional techniques, a rapid overview of mammal diversity with broad applications to monitoring, management and conservation. By including appropriate genetic markers and updated reference databases, eDNA metabarcoding method can be extended to the whole vertebrate community.


Assuntos
DNA Ambiental , Animais , Biodiversidade , Código de Barras de DNA Taxonômico , Monitoramento Ambiental , Florestas , Mamíferos/genética
4.
Aten Primaria ; 53(5): 102041, 2021 05.
Artigo em Espanhol | MEDLINE | ID: mdl-33780900

RESUMO

OBJECTIVE: To describe the health-related quality of life (HRQoL) in benzodiazepine users and to verify whether there is an association with the characteristics of the treatment, its effectiveness, and the sociodemographic variables. DESIGN: Descriptive cross-sectional study. LOCATION: Family medicine consultations. PARTICIPANTS: Four hundred and fifty 2patients over 18 years of age consuming benzodiazepines or similar drugs. MAIN MEASUREMENTS: HRQoL was assessed using the EuroQol5-D questionnaire. Other variables: symptoms of anxiety or insomnia, sociodemographic variables and characteristics of the treatment. RESULTS: The mean score in health status was 62.80 (95% CI: 60.69-64.86), lower in people without studies (59.27±21.97 SD; P=.004) and lower social category (60.02±21.27 SD; P<.001). Regarding the social rate (EQ index), a mean score of 0.6025 (95% CI: 0.5659-0.6391) was obtained, higher in people with higher education (0.6577±0.3574 SD; P=.001), plus social category (0.7286±0.3381 SD; P<.001) and age less than 65 years (0.6603±0.3426 SD; P<.001). The variables that were associated with the value of the EQ index by means of multiple regression were absence of anxiety/insomnia, belonging to higher social classes, age less than 65 years and less consumption of anxiolytics/hypnotics. CONCLUSIONS: Patients who use benzodiazepines show, despite treatment, a moderate HRQL, lower than that obtained in the general population or in primary care patients. The situation is more favorable in the youngest, in those who do not present anxiety/insomnia, in those belonging to higher social classes and when the consumption of drugs is lower.


Assuntos
Benzodiazepinas , Qualidade de Vida , Adolescente , Adulto , Idoso , Estudos Transversais , Nível de Saúde , Humanos , Inquéritos e Questionários
7.
PLoS One ; 19(1): e0296305, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38165899

RESUMO

Peru ranks among the three countries with the highest bird species diversity globally and a majority of those species are found in the Peruvian Amazon. However, birds in this area are currently facing serious anthropogenic threats. Genetic and genomic methods are becoming important tools for avian biodiversity monitoring and conservation planning. Comprehensive molecular libraries that are publicly available are key to the effective deployment of these tools. We analyze the information gaps for four molecular markers in the most important genetic sequence databases, Barcode of Life Data Systems (BOLD) and NCBI GenBank, for bird species of the Peruvian Amazonia. We found that 64% of Peruvian Amazonian bird species have gene sequences for COI, 59.5% have CYTB sequences, 16.4% have 12S sequences, and only 0.6% have 18S sequences. However, these numbers decrease drastically to 4.3% for COI sequences when we only consider specimens sampled in Peru. Our data also showed that 43.8% of Peruvian Amazonian endemic species (n = 32) are missing sequences of any screened marker uploaded to GenBank or BOLD. Our results will encourage and guide efforts of the scientific community to complete reference libraries for Peruvian avian species that will be useful for future DNA-based monitoring projects that include birds.


Assuntos
Biodiversidade , Aves , Animais , Peru , Aves/genética , Brasil
9.
An Bras Dermatol ; 92(5 Suppl 1): 113-114, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29267465

RESUMO

Osteoma cutis or cutaneous ossification is a rare entity characterized by the formation of bone in the skin. We present an isolated primary osteoma cutis located on the palm, an atypical location.


Assuntos
Doenças Ósseas Metabólicas/patologia , Dermatoses da Mão/patologia , Ossificação Heterotópica/patologia , Dermatopatias Genéticas/patologia , Adulto , Biópsia , Humanos , Masculino , Dor/etiologia , Doenças Raras
10.
Rev. peru. biol. (Impr.) ; 27(2): 241-250, abr.-jun 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1144955

RESUMO

Resumen En el Perú se registran al menos 180 especies de murciélagos. Sin embargo, son pocos los estudios acerca de sus ectoparásitos, dentro de los cuales destacan las denominadas moscas de murciélagos (Diptera: Streblidae y Nycteribiidae), en los cuales se estima un total de 158 especies en la región Neotropical. En el Perú, una de las regiones con menos información es la costa. En este estudio actualizamos el conocimiento de las asociaciones ectoparásito-hospedero en murciélagos de la costa peruana, una de las regiones ecologicas con más degradación y pérdida de hábitat. Se evaluaron cinco localidades en las regiones de Piura, Lima y Tacna. Se capturaron 85 murciélagos pertenecientes a 7 especies; 4 de Phyllostomidae, 2 de Molossidae y 1 de Vespertilionidae. Se encontraron seis especies de dípteros (Diptera: Streblidae) y un hemíptero (Hemiptera: Polyctenidae) y se reporta por primera vez algunas de estas asociaciones en las regiones de Lima y Piura. Se reporta también a Anoura peruana como hospedero de Anastrebla modestini (Streblidae) en una colonia reproductiva compartida con Platalina genovensium, y por primera vez para la región de Piura, el co-parasitismo de los estréblidos Megistopoda aranea, Aspidoptera phyllostomatis y Metelasmus pseudopterus en un mismo individuo de Artibeus fraterculus.


Abstract There are at least 180 species of bats in Peru. However, there are few studies about ectoparasites of bats, among which the so-called bat flies (Diptera: Streblidae and Nycteribiidae) stand out, with a total of 158 species estimated for the Neotropical region. In Peru, one of the ecological regions with the least information is the coast. In this study we updated the knowledge of the ectoparasite-host associations in bats from the Peruvian coast, one of the regions of the country with the most degradation and loss of habitat. Five locations in the Piura, Lima and Tacna regions were evaluated. 85 bats belonging to 7 species were captured: 4 from Phyllostomidae, 2 from Molossidae and 1 from Vespertilionidae. Six dipterous species (Diptera: Streblidae) and one Hemiptera species (Hemiptera: Polyctenidae) were found and some of these associations are reported for the first time in the Lima and Piura regions. Anoura peruana is also reported as the host of Anastrebla modestini (Streblidae) in a reproductive colony shared with Platalina genovensium, and for the first time for the Piura region, the co-parasitism of the Megistopoda aranea, Aspidoptera phyllostomatis and Metelasmus pseudopterus in a same individual of Artibeus fraterculus.

12.
Rev. peru. biol. (Impr.) ; 25(2): 91-110, Apr.-Jun. 2018. ilus
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1094306

RESUMO

El Santuario Nacional Tabaconas Namballe (SNTN) se encuentra en el límite de distribución de muchas especies endémicas de los Andes del Norte, en un área amenazada por la deforestación y con muchos vacíos de información ornitológica. Reportamos una lista actualizada de la diversidad de aves del Santuario, así como de sus especies de interés de conservación. Para lo cual se evaluaron tres localidades representativas: Páramos, Chichilapa y El Sauce, durante la época seca (setiembre, octubre - 2014) y de lluvia (marzo, abril - 2015). Se aplicaron varios métodos complementarios: puntos de conteo, capturas con redes de niebla, transectos nocturnos y registros asistemáticos. Se registró 197 (40 familias) y 153 (39 familias) especies en época seca y de lluvia respectivamente, con un total de 226 especies y 42 familias. Para el listado final se incluyeron registros de un promedio de 45 cámaras trampa, operativas desde agosto 2014 hasta abril 2015, más registros concluyentes de evaluaciones ornitológicas previas. Este trabajo reporta 82 nuevos registros de aves para el Santuario, 7 de los cuales provienen de cámaras trampa. En este sentido, la diversidad total de aves del Santuario es 290 especies y 46 familias. Aparte de las 45 especies entre endémicos, amenazados y casi amenazados de extinción, se destaca el nuevo registro para la región Cajamarca la Perdiz Gris Tinamus tao. Los resultados encontrados sugieren que aún falta mucho por conocer sobre la diversidad de aves del Santuario; sin embargo, resalta el rol clave del área protegida para la conservación de aves de esta región


The Tabaconas Namballe National Sanctuary (TNNS) is located at the limit of distribution of many endemic species from the Northern Andes, in an area threatened by deforestation and with many gaps in ornithological information. We report an updated list of species of the Sanctuary, and identify those species of conservation concern. We sampled three representative sites: Páramos, Chichilapa and El Sauce, during the dry season (September-October in 2014) and rainy season (March-April in 2015). We employed several complementary methods: counting points, mist-nets, nocturnal transects and non-systematic records. We recorded 197 (40 families) and 153 (39 families) species in the dry and rainy seasons respectively, with a total of 226 species and 42 families. In order to get an updated checklist, we include records of an average of 45 trap cameras, operative from August 2014 to April 2015, and we compile conclusive records from previous ornithological assessments. This work reports 82 new records of birds of the Sanctuary, 7 of which come from camera traps. In this way, the bird diversity of the Sanctuary is 290 species and 46 families. In addition to the 45 species between endemic, threatened and near threatened with extinction, we highlight a new record from the region Cajamarca, the Gray Tinamou Tinamus tao. Our results suggest that there is still much to know about the diversity of birds in the Sanctuary, however, it highlights the key role of this protected area in terms of bird conservation in this region

15.
An. bras. dermatol ; 92(5,supl.1): 113-114, 2017. graf
Artigo em Inglês | LILACS | ID: biblio-887069

RESUMO

Abstract Osteoma cutis or cutaneous ossification is a rare entity characterized by the formation of bone in the skin. We present an isolated primary osteoma cutis located on the palm, an atypical location.


Assuntos
Humanos , Masculino , Adulto , Dermatopatias Genéticas/patologia , Doenças Ósseas Metabólicas/patologia , Ossificação Heterotópica/patologia , Dermatoses da Mão/patologia , Dor/etiologia , Biópsia , Doenças Raras
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