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1.
Environ Monit Assess ; 195(12): 1478, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37966615

RESUMO

Forest resource reporting techniques primarily use the two most recent measurements for understanding forest change. Multiple remeasurements now exist within the US national forest inventory (NFI), providing an opportunity to examine long-term forest demographics. We leverage two decades of remeasurements to quantify live-dead wood demographics which can better inform estimates of resource changes in forest ecosystems. Our overall objective is to identify opportunities and gaps in tracking 20 years of forest demographics within the US NFI using east Texas as a pilot study region given its diversity of tree species, prevalence of managed conditions, frequency of disturbances, and relatively rapid change driven by a warm, humid climate. We examine growth and mortality rates, identify transitions to downed dead wood/litter and removal via harvest, and describe implications of these processes focusing on key species groups (i.e., loblolly pine, post oak, and water oak) and size classes (i.e., saplings, small and large trees). Growth and mortality rates fluctuated differently over time by species and stem sizes in response to large-scale disturbances, namely the 2011 drought in Texas. Tree-fall rates were highest in saplings and snag-fall rates trended higher in smaller trees. For removal rates, different stem sizes generally followed similar patterns within each species group. Forest demographics from the field-based US NFI are informative for identifying diffuse lagged mortality, species- and size-specific effects, and management effects. Moreover, researchers continually seek to employ ancillary data and develop new statistical methods to enhance understanding of forest resource changes from field-based inventories.


Assuntos
Ecossistema , Quercus , Projetos Piloto , Texas , Monitoramento Ambiental , Florestas , Árvores , Demografia
2.
Acta Psychol (Amst) ; 221: 103441, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34739902

RESUMO

Hugging is one of the most common types of affective touch encountered in everyday life. However, little is known about the factors that influence hugging evaluation and behaviour. Here, we aimed to assess how different hugs would be evaluated and whether they can affect mood. Furthermore, we aimed to investigate what kind of arm crossing is common in a naturalistic setting and whether arm crossing style could be predicted from gender, emotional closeness, and the height difference of huggers. We conducted two studies addressing these questions. In study 1, participants hugged a confederate for 1 second (s), 5 s or 10 s with two different arm crossing styles and reported how pleasant, arousing and under control the touch felt. Additionally, participants were asked about their mood ("self-ratings") immediately after, 3 minutes (min) after and 6 min after each hug. In study 2, participants were approached on campus and asked to share a hug, with arm crossing style being the dependent variable. The height difference, gender and self-rated emotional closeness to the hug partner were recorded as possible predictors for arm crossing style. Results from study 1 indicate that duration matters more than arm crossing style for hug pleasure, arousal, and control, with 1 s hugs being rated as least pleasant and under control than 5 s and 10 s hugs. Accordingly, 1 s hugs also resulted in lower pleasure self-ratings immediately post hug than 5 s and 10 s hugs. Arousal self-ratings were higher immediately post hug than several minutes after a hug. In study 2, gender was linked to arm crossing style, with male-male hug dyads exhibiting a different hugging style from female-female dyads. These findings are discussed in relation to previous hug research and gender differences in touch behaviour.


Assuntos
Braço , Percepção do Tato , Afeto , Emoções , Feminino , Humanos , Masculino , Tato
3.
PLoS One ; 15(3): e0229835, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32176706

RESUMO

Quantifying the economic impacts of invasive species is an essential step in developing and prioritizing invasive species management. In particular, kudzu, Pueraria montana (Lour.) Merr. is an aggressive and non-native vine that not only causes ecological damage and reduces biodiversity, but can have multiple economic consequences such as loss of timber value and volume. Using current infestation locations in Oklahoma, southcentral USA, a Monte Carlo simulation was run to estimate the natural as well as anthropogenic spread rate of kudzu in the next five years. Simulations were supplemented with an economic impact analysis within the Impact Analysis for PLANing (IMPLAN) platform. To account for economic loss in the forest product industry, a replacement cost approach with a sensitivity analysis was conducted. Occurrence data collections revealed that current kudzu populations are already established in Oklahoma forests. The results demonstrate that by year five, total industry output could be reduced by $167.9 million, which will influence 780 jobs in the most extreme case scenario. The predicted economic loss due to kudzu expansion could act as an incentive for appropriate management practices and plans to be implemented.


Assuntos
Espécies Introduzidas/economia , Pueraria/crescimento & desenvolvimento , Agricultura Florestal/métodos , Oklahoma
4.
Ecol Appl ; 26(2): 602-11, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27209798

RESUMO

Significant areas of the southern USA periodically experience intense drought that can lead to episodic tree mortality events. Because drought tolerance varies among species and size of trees, such events can alter the structure and function of terrestrial ecosystem in ways that are difficult to detect with local data sets or solely with remote-sensing platforms. We investigated a widespread tree mortality event that resulted from the worst 1-year drought on record for the state of Texas, USA. The drought affected ecoregions spanning mesic to semiarid climate zones and provided a unique opportunity to test hypotheses related to how trees of varying genus and size were affected. The study was based on an extensive set of 599 distributed plots, each 0.16 ha, surveyed in the summer following the drought. In each plot, dead trees larger than 12.7 cm in diameter were counted, sized, and identified to the genus level. Estimates of total mortality were obtained for each of 10 regions using a combination of design-based estimators and calibrated remote sensing using MODIS 1-yr change in normalized difference vegetation index products developed by the U.S. Forest Service. As compared with most of the publicized extreme die-off events, this study documents relatively low rates of mortality occurring over a very large area. However, statewide, regional tree mortality was massive, with an estimated 6.2% of the live trees perishing, nearly nine times greater than normal annual mortality. Dead tree diameters averaged larger than the live trees for most ecoregions, and this trend was most pronounced in the wetter climate zones, suggesting a potential re-ordering of species dominance and downward trend in tree size that was specific to climatic regions. The net effect on carbon storage was estimated to be a redistribution of 24-30 Tg C from the live tree to dead tree carbon pool. The dead tree survey documented drought mortality in more than 29 genera across all regions, and surprisingly, drought resistant and sensitive species fared similarly in some regions. Both angiosperms and gymnosperms were affected. These results highlight that drought-driven mortality alters forest structure differently across climatic regions and genera.


Assuntos
Secas , Ecossistema , Árvores/classificação , Árvores/fisiologia , Chuva , Texas , Fatores de Tempo
5.
Hum Psychopharmacol ; 24(5): 371-89, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19565524

RESUMO

OBJECTIVES: In clinical drug development, wakefulness and wake-promotion may be assessed by a large number of scales and questionnaires. Objective assessment of wakefulness is most commonly made using sleep latency/maintenance of wakefulness tests, polysomnography and/or behavioral measures. The purpose of the present review is to highlight the degree of overlap in the assessment of wakefulness and cognition, with consideration of assessment techniques and the underlying neurobiology of both concepts. DESIGN: Reviews of four key areas were conducted: commonly used techniques in the assessment of wakefulness; neurobiology of sleep/wake and cognition; targets of wake promoting and/or cognition enhancing drugs; and ongoing clinical trials investigating wake promoting effects. RESULTS: There is clear overlap between the assessment of wakefulness and cognition. There are common techniques which may be used to assess both concepts; aspects of the neurobiology of both concepts may be closely related; and wake-promoting drugs may have nootropic properties (and vice versa). Clinical trials of wake-promoting drugs often, though not routinely, assess aspects of cognition. CONCLUSIONS: Routine and broad assessment of cognition in the development of wake-promoting drugs may reveal important nootropic effects, which are not secondary to alertness/wakefulness, whilst existing cognitive enhancers may have underexplored or unknown wake promoting properties.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Cognição/efeitos dos fármacos , Vigília/efeitos dos fármacos , Vigília/fisiologia , Encéfalo/anatomia & histologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Ritmo Circadiano/efeitos dos fármacos , Ensaios Clínicos como Assunto , Humanos , Testes Neuropsicológicos , Sono/efeitos dos fármacos , Inquéritos e Questionários
6.
J Clin Pharmacol ; 47(3): 315-22, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17322143

RESUMO

Dapoxetine is being investigated for the treatment of premature ejaculation. This study evaluated the potential pharmacokinetic and cognitive interactions of dapoxetine 60 mg with ethanol 0.5 g/kg in a single-center, double-blind, randomized, placebo-controlled crossover study in healthy adult male participants (n = 24). Dapoxetine was rapidly absorbed and eliminated; peak concentrations were noted 1.47 hours after administration and decreased with an alpha half-life of 1.33 hours and a terminal half-life of 15.6 hours. Pharmacokinetic parameters (C(max), AUC(infinity), t((1/2)), and t(max)) of dapoxetine were not altered with concurrent ethanol consumption. Furthermore, coadministration of dapoxetine did not affect the pharmacokinetics of ethanol or potentiate the cognitive and subjective effects of ethanol.


Assuntos
Benzilaminas/farmacocinética , Cognição/efeitos dos fármacos , Etanol/farmacocinética , Naftalenos/farmacocinética , Adulto , Área Sob a Curva , Astenia/induzido quimicamente , Benzilaminas/administração & dosagem , Benzilaminas/efeitos adversos , Depressores do Sistema Nervoso Central/administração & dosagem , Depressores do Sistema Nervoso Central/farmacocinética , Estudos Cross-Over , Distúrbios do Sono por Sonolência Excessiva/induzido quimicamente , Método Duplo-Cego , Interações Medicamentosas , Etanol/administração & dosagem , Meia-Vida , Cefaleia/induzido quimicamente , Humanos , Masculino , Naftalenos/administração & dosagem , Naftalenos/efeitos adversos , Testes Neuropsicológicos , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Inibidores Seletivos de Recaptação de Serotonina/farmacocinética , Comprimidos , Baixa Visão/induzido quimicamente
7.
Environ Monit Assess ; 122(1-3): 289-307, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16770497

RESUMO

The sensitivity of the United States Forest Health Monitoring network to outbreaks of defoliating insects was examined by means of a simulation study. A model constructed specifically for the study was used to generate a wide variety of defoliation patterns in forested landscapes. Forest configuration was that of Minnesota, USA, as expressed by the GAP land cover classification. Combinations of model parameters were based on a Latin Hypercube sample. The relationship between the average number of plots defoliated and outbreak characteristics was then examined via multiple regression. Both theoretical and model results pointed to a strong, linear relationship between the average number of plots defoliated and outbreak size. Model results provided additional insight, suggesting a significant relationship between the average number of plots defoliated and other outbreak characteristics after outbreak size was taken into account.


Assuntos
Simulação por Computador , Monitoramento Ambiental , Agricultura Florestal , Insetos , Modelos Biológicos , Animais , Projetos de Pesquisa
8.
Schizophr Res ; 73(2-3): 311-8, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15653276

RESUMO

Impaired auditory sensory gating is considered characteristic of schizophrenia and a marker of the information processing deficit inherent to that disorder. Predominance of negative symptoms also reflects the degree of deficit in schizophrenia and is associated with poorer pre-morbid functioning, lower IQ, and poorer outcomes. However, a consistent relationship between auditory sensory gating and negative symptoms in schizophrenia has yet to be demonstrated. The absence of such a finding is surprising, since both impaired auditory gating and negative symptoms have been linked with impaired fronto-temporal cortical function. The present study measured auditory gating using the P50 event related potential (ERP) in a paired-click paradigm and capitalized on the relative localization advantage of magnetoencephalography (MEG) to assess auditory sensory gating in terms of the event related field (ERF) M50 source dipoles on bilateral superior temporal gyrus (STG). The primary hypothesis was that there would be a positive correlation between lateralized M50 auditory sensory gating measures and negative symptoms in patients with schizophrenia. A standard paired-click paradigm was used during simultaneous EEG and MEG data collection to determine S2/S1 sensory gating ratios in a group of 20 patients for both neuroimaging techniques. Participants were administered the Schedule for the Assessment of Negative Symptoms (SANS), the Positive and Negative Symptom Scale (PANSS), and the Calgary Depression Scale for Schizophrenia. Consistent with previous reports, there was no relationship between ERP P50 sensory gating and negative symptoms. However, right (not left) hemisphere ERF M50 sensory gating ratio was significantly and positively correlated with negative symptoms. This finding is compatible with information processing theories of negative symptoms and with more recent findings of fronto-temporal abnormality in patients with predominantly negative symptoms.


Assuntos
Processos Mentais/fisiologia , Transtornos da Percepção/etiologia , Esquizofrenia/complicações , Esquizofrenia/fisiopatologia , Lobo Temporal/fisiopatologia , Adolescente , Adulto , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Transtornos da Percepção/diagnóstico , Escalas de Graduação Psiquiátrica , Esquizofrenia/diagnóstico , Índice de Gravidade de Doença
9.
Neuroreport ; 14(14): 1841-5, 2003 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-14534432

RESUMO

To evaluate the role of the fusiform gyrus in identifying and processing facial emotional expression in humans, MEG data were collected while six healthy subjects judged whether photographs of faces displayed emotion (happiness or disgust) compared to neutral faces and equiluminant scrambled faces. For all six subjects, a magnetic source localizing to right fusiform gyrus was evident approximately 150 ms following presentation of face stimuli, but not following non-face stimuli. MEG source strength for this component was greatest for happy, intermediate for disgust, and lowest for neutral facial expressions, suggesting that activity in fusiform gyrus is sensitive to both face-specific stimuli and to the affective content of the face. These findings are considered in the context of a specialized neural face-dependent information system.


Assuntos
Afeto/fisiologia , Atenção/fisiologia , Expressão Facial , Reconhecimento Visual de Modelos/fisiologia , Percepção Visual/fisiologia , Adulto , Análise de Variância , Mapeamento Encefálico , Dominância Cerebral , Eletroencefalografia , Face , Giro do Cíngulo/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Magnetoencefalografia/métodos , Estimulação Luminosa
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