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1.
Biota Neotrop. (Online, Ed. ingl.) ; 18(3): e20170487, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951195

RESUMO

Abstract: The implementation of private areas focused on conservation of species and habitats, combined with REDD+ policies, has become an important ally for biodiversity conservation, expanding the conservation areas of the most varied habitats, covering key groups such as large mammals, which are extremely important for the maintenance of ecosystem services. In the upper region of the Purus River in Acre, Brazil, an inventory was carried out using camera-traps, of medium and large mammals community in a private REDD+ area, known as the Purus Project. A total of 19 species of mammals were recorded with an effort of 1859 trap-nigths, including rare, endangered and key species. It is estimated that the richness for the area is of 22 species. Endangered and rare species such as the tapir (Tapirus terrestris) and the short-eared dog (Atelocynus microtis) presented high rates of relative abundance compared to other Conservation Units (UCs). The richness of medium to large-sized mammals recorded in the Purus Project underscores the importance of REDD+ in private areas for the conservation of this group, given the challenges for inclusion and creation of new protected areas. REDD+ projects in privates' areas become an important component for conservation of species and the connection between public conservation units favoring the spread of species and populations between areas, and consequently the gene flow.


Resumo: A implementação de áreas privadas voltadas para conservação de espécies e habitats, aliadas a políticas de REDD+, tem se tornado importante aliada para conservação da biodiversidade, ampliando as regiões de conservação dos mais variados habitats, abrangendo grupos chaves como grandes mamíferos, extremamente importantes para manutenção dos serviços ecossistêmicos. Na região do alto rio Purus, Acre, Brasil, foi realizado um inventário utilizando armadilhas fotográficas, da comunidade de mamíferos de médio e grande porte de uma área privada de REDD+, o Projeto Purus. Foram registradas 19 espécies de mamíferos, com um esforço de 1.859 armadilhas-noite, incluindo chaves, raras e ameaçadas de extinção. Estima-se que a riqueza esperada para a área seja de 22 espécies. Espécies ameaçadas e raras como a Anta (Tapirus terrestris) e o Cachorro-do-mato (Atelocynus microtis) apresentaram taxas de abundância relativa elevadas, comparadas com outras UCs. A riqueza de médios e grandes mamíferos registrados na região do Projeto Purus ressalta a importância de REDD+ em áreas privadas para conservação deste grupo, dado os desafios para inclusão e criação de novas áreas protegidas públicas. Assim projetos de REDD+ em áreas privadas se tornam um importante componente para conservação de espécies e para a conexão entre Unidades de Conservação públicas favorecendo a dispersão de espécies e populações entre áreas, e consequentemente o fluxo gênico.

2.
Adv Mater ; 29(26)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28464394

RESUMO

A variety of emergent phenomena have been enabled by interface engineering in complex oxides. The existence of an intrinsic interfacial layer has often been found at oxide heterointerfaces. However, the role of such an interlayerin controlling functionalities is not fully explored. Here, we report the control of the exchange bias (EB) in single-phase manganite thin films with nominallyuniform chemical composition across the interfaces. The sign of EB depends on the magnitude of the cooling field. A pinned layer, confirmed by polarized neutron reflectometry, provides the source of unidirectional anisotropy. The origin of the exchange bias coupling is discussed in terms of magnetic interactions between the interfacial ferromagnetically reduced layer and the bulk ferromagnetic region. The sign of EB is related to the frustration of antiferromagnetic coupling between the ferromagnetic region and the pinned layer. Our results shed new light on using oxide interfaces to design functional spintronic devices.

3.
Nat Commun ; 6: 8199, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26354002

RESUMO

Rapid proton migration is a key process in hydrocarbon photochemistry. Charge migration and subsequent proton motion can mitigate radiation damage when heavier atoms absorb X-rays. If rapid enough, this can improve the fidelity of diffract-before-destroy measurements of biomolecular structure at X-ray-free electron lasers. Here we study X-ray-initiated isomerization of acetylene, a model for proton dynamics in hydrocarbons. Our time-resolved measurements capture the transient motion of protons following X-ray ionization of carbon K-shell electrons. We Coulomb-explode the molecule with a second precisely delayed X-ray pulse and then record all the fragment momenta. These snapshots at different delays are combined into a 'molecular movie' of the evolving molecule, which shows substantial proton redistribution within the first 12 fs. We conclude that significant proton motion occurs on a timescale comparable to the Auger relaxation that refills the K-shell vacancy.

4.
Phys Rev Lett ; 108(25): 253006, 2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-23004597

RESUMO

We report the first study of UV-induced photoisomerization probed via core ionization by an x-ray laser. We investigated x-ray ionization and fragmentation of the cyclohexadiene-hexatriene system at 850 eV during the ring opening. We find that the ion-fragmentation patterns evolve over a picosecond, reflecting a change in the state of excitation and the molecular geometry: the average kinetic energy per ion fragment and H(+)-ion count increase as the ring opens and the molecule elongates. We discuss new opportunities for molecular photophysics created by optical pump x-ray probe experiments.


Assuntos
Alcenos/química , Ciclização/efeitos da radiação , Cicloexenos/química , Polienos/química , Processos Fotoquímicos , Espectrofotometria Ultravioleta , Termodinâmica , Raios X
5.
Phys Rev Lett ; 107(8): 083001, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21929165

RESUMO

High harmonic spectra show that laser-induced strong field ionization of water has a significant contribution from an inner-valence orbital. Our experiment uses the ratio of H(2)O and D(2)O high harmonic yields to isolate the characteristic nuclear motion of the molecular ionic states. The nuclear motion initiated via ionization of the highest occupied molecular orbital (HOMO) is small and is expected to lead to similar harmonic yields for the two isotopes. In contrast, ionization of the second least bound orbital (HOMO-1) exhibits itself via a strong bending motion which creates a significant isotope effect. We elaborate on this interpretation by solving the time-dependent Schrödinger equation to simulate strong field ionization and high harmonic generation from the water isotopes. We expect that this isotope marking scheme for probing excited ionic states in strong field processes can be generalized to other molecules.

6.
J Nerv Ment Dis ; 197(7): 476-83, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19597354

RESUMO

Few studies have examined age of onset and chronicity of depression in the same subject sample. The present study sought to determine whether personality traits related to early onset depression were different from those related to chronic depression. We tested the associations between personality self-reports and clinical characteristics of depression by conducting multiple and logistic regression analyses to determine whether personality uniquely predicted clinical characteristics and whether clinical characteristics uniquely predicted personality, after adjusting for depression severity. We also analyzed data at 6-month follow-up to determine whether age of onset and chronicity maintained their associations with personality. The study found that low levels of positive personality traits had unique associations with chronicity of depression, whereas elevated levels of negative personality traits had unique associations with an earlier onset of depression. Furthermore, associations were generally maintained over time, suggesting that associations between personality and these depression subtypes are stable.


Assuntos
Transtorno Depressivo Maior/diagnóstico , Inventário de Personalidade , Adulto , Idade de Início , Doença Crônica , Transtorno Depressivo Maior/classificação , Transtorno Distímico/diagnóstico , Emoções , Feminino , Seguimentos , Humanos , Masculino , Personalidade/classificação , Inventário de Personalidade/estatística & dados numéricos , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Análise de Regressão , Índice de Gravidade de Doença , Inquéritos e Questionários
7.
Depress Anxiety ; 26(2): 117-22, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18972567

RESUMO

OBJECTIVES: This study compared depressed and nondepressed participants' emotional reactivity to anticipated reward, anticipated punishment, failure to obtain a reward, and successful avoidance of punishment. EXPERIMENTAL DESIGN: This study compared residualized change scores on target emotions for currently depressed (n=19), previously depressed (n=19), and never-depressed (n=43) participants during four experimental conditions: anticipated reward (cash), anticipated punishment (cold pressor), nonreward (failure to earn cash), and avoidance (successful avoidance of a cold pressor). PRINCIPAL OBSERVATIONS: Currently depressed participants' reactivity in response to anticipated reward was significantly diminished compared with never depressed participants', and marginally diminished compared with previously depressed participants'. Currently depressed, previously depressed, and never-depressed participants did not differ significantly in their emotional reactivity to anticipated punishment or to nonreward or avoidance. CONCLUSIONS: These results suggest that depressed individuals' diminished emotional reactivity may be mainly a state effect and may be limited to anticipated reward.


Assuntos
Nível de Alerta , Aprendizagem da Esquiva , Transtorno Depressivo Maior/psicologia , Transtorno Distímico/psicologia , Emoções , Motivação , Punição , Recompensa , Adolescente , Adulto , Retroalimentação Psicológica , Feminino , Humanos , Masculino , Orientação , Reconhecimento Visual de Modelos , Inventário de Personalidade , Resolução de Problemas , Valores de Referência , Semântica , Adulto Jovem
8.
Science ; 322(5905): 1232-5, 2008 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-18974318

RESUMO

Molecular electronic states energetically below the highest occupied molecular orbital (HOMO) should contribute to laser-driven high harmonic generation (HHG), but this behavior has not been observed previously. Our measurements of the HHG spectrum of N2 molecules aligned perpendicular to the laser polarization showed a maximum at the rotational half-revival. This feature indicates the influence of electrons occupying the orbital just below the N2 HOMO, referred to as the HOMO-1. Such observations of lower-lying orbitals are essential to understanding subfemtosecond/subangstrom electronic motion in laser-excited molecules.

9.
J Affect Disord ; 91(2-3): 229-34, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16487598

RESUMO

BACKGROUND: Behavioral activation system (BAS) deficits are hypothesized to increase risk for depression. This study tested the hypothesis that BAS deficits, measured with both self-report and electrophysiological methods, would predict the six-month course of depression. METHODS: 67 participants with major depressive disorder (MDD) with or without pre-existing dysthymia were assessed at baseline with Carver and White's [Carver, C.S., White, T.L., 1994. Behavioral inhibition, behavioral activation, and affective responses to impending reward and punishment: the BIS/BAS scales. J. Pers. Soc. Psychol. 67, 319-333.] BIS/BAS scales and resting EEG. The week-by-week course of their depressive symptoms was assessed six months later with the Longitudinal Interval Follow-up Evaluation (LIFE). RESULTS: Baseline self-reported BAS sensitivity predicted depression diagnosis (MDD or dysthymia) at follow-up, number of MDD symptoms at follow-up, average weekly level of depression, and time to recovery. These effects persisted after controlling for baseline clinical variables associated with a worse course. Baseline resting EEG alpha asymmetry did not significantly predict the course of depression. LIMITATIONS: Although BAS sensitivity predicted the subsequent course of depression, we cannot determine whether it played a causal role in maintaining depression. CONCLUSIONS: Lower self-reported BAS sensitivity predicts a worse course of depression but EEG asymmetries do not.


Assuntos
Transtorno Depressivo Maior/epidemiologia , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Adolescente , Adulto , Manual Diagnóstico e Estatístico de Transtornos Mentais , Eletroencefalografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Descanso
10.
Compr Psychiatry ; 46(4): 246-53, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16175754

RESUMO

Little is known about long-term treatment use among patients with dysthymia. This paper describes patterns of treatment use by 85 outpatients with dysthymic disorder and a comparison group of 36 outpatients with nonchronic (episodic) major depression in a naturalistic follow-up. Patients with dysthymia had higher rates of treatment use across 7 1/2 years compared with patients with episodic major depression. Baseline variables that predicted which patients with dysthymia dropped out of treatment before recovering from dysthymic disorder included age, ethnicity, Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition Axis II pathology as obtained from informant reports, higher self-reported autonomy, and receiving psychotherapy alone as compared to receiving a combination of psychotherapy and medication. Dysthymic disorder places a significant burden on the mental health services system, yet many outpatients with dysthymia may be receiving inadequate treatment. Younger patients, ethnic minority patients, and patients with personality disorders may be at increased risk of dropping out from treatment for depression. Combination treatments may increase treatment retention.


Assuntos
Transtorno Depressivo Maior/terapia , Tratamento Farmacológico/métodos , Transtorno Distímico/terapia , Serviços de Saúde Mental/estatística & dados numéricos , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Psicoterapia/métodos , Adolescente , Adulto , Efeitos Psicossociais da Doença , Transtorno Depressivo Maior/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Transtorno Distímico/diagnóstico , Cuidado Periódico , Feminino , Seguimentos , Humanos , Masculino , Serviços de Saúde Mental/normas , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Qualidade da Assistência à Saúde , Estados Unidos
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