599 research outputs found

    Monitoring lianas from space: using Sentinel-2 imagery to observe liana removal in logged tropical forests

    Get PDF
    Liana removal – the cutting of over-abundant woody climbing plants (lianas) – has the potential to substantially increase tree growth and biomass accumulation across millions of hectares of degraded tropical forest. Satellite imagery could provide data capable of observing the effect of liana removal on the forest canopy, enabling the large-scale monitoring and validation of liana removal, which remains a key hurdle to its widespread implementation. Using a 320-ha liana removal experiment in Sabah, Malaysian Borneo, we tested whether a time series of Sentinel-2 images could observe the canopy signature of liana removal. Calculating a range of metrics derived from the Normalized Burn Ratio – a vegetation index based on spectral reflectance that differentiates leaf from non-leaf – we quantified satellite-derived canopy disturbance and fragmentation across a range of liana removal intensities and examined how canopy disturbance changed in the 12-months following removal treatments. We find that liana removal significantly increases canopy disturbance and fragmentation metrics one month after removal, with partial removal having a smaller effect than complete removal. The impact of liana removal on the canopy metrics declined over time, with measures of canopy disturbance and fragmentation largely indistinguishable from control forest within 12-months of treatment. Our findings evidence that freely available satellite imagery can be used to efficiently monitor large-scale liana removal applied at a range of intensities and suggest that partial liana removal could significantly reduce canopy disturbance of this restoration method

    Treatment Precedes Positive Symptoms in North American Adolescent and Young Adult Clinical High Risk Cohort

    Get PDF
    Early intervention for psychotic disorders, a growing international priority, typically targets help-seeking populations with emerging psychotic (“positive”) symptoms. We assessed the nature of and degree to which treatment of individuals at high risk for psychosis preceded or followed the onset of positive symptoms. The North American Prodrome Longitudinal Study–2 collected psychosocial treatment histories for 745 (98%) of 764 high-risk participants (M age = 18.9, 57% male, 57.5% Caucasian, 19.1% Hispanic) recruited from 8 North American communities. Similar to prior findings, 82% of participants reported psychosocial treatment prior to baseline assessment, albeit with significant variability across sites (71%–96%). Participants first received treatment a median of 1.7 years prior to the onset of a recognizable psychosis-risk syndrome. Only one fourth sought initial treatment in the year following syndrome onset. Although mean sample age differed significantly by site, age at initial treatment (M = 14.1, SD = 5.0) did not. High rates of early treatment prior to syndrome onset make sense in light of known developmental precursors to psychotic disorders but are inconsistent with the low rates of treatment retrospectively reported by first-episode psychosis samples. Findings suggest that psychosis risk studies and clinics may need to more actively recruit and engage symptomatic but non-help-seeking individuals and that community clinicians be better trained to recognize both positive and nonspecific indicators of emerging psychosis. Improved treatments for nonspecific symptoms, as well as the characteristic attenuated positive symptoms, are needed

    Depression and clinical high-risk states: Baseline presentation of depressed vs. non-depressed participants in the NAPLS-2 cohort

    Get PDF
    Depressed mood appears to be highly prevalent in clinical high risk (CHR) samples. However, many prior CHR studies utilize modest size samples and do not report on the specific impact of depression on CHR symptoms. The aim of the current paper is to investigate the prevalence of depressive disorders and the impact of lifetime depression on baseline clinical presentation and longitudinal outcomes in a large cohort of individuals meeting CHR criteria in the second phase of the North American Prodrome Longitudinal Study (NAPLS-2). Depression was assessed both categorically (via DSM-IV-TR diagnoses) and symptomatically (using a clinician-rated scale of depressive symptoms) within a sample of 764 individuals at CHR and 279 controls. Current and lifetime depressive disorders were highly prevalent (60%) in this sample. Depression diagnoses were associated with more pronounced negative and general symptoms; individuals with remitted depression had significantly less severe negative, disorganized, and general symptoms and better social and role functioning relative to those with current depression. Current mood disturbance, as measured by scores on a clinician-rated symptom scale, contributed beyond the impact of positive and negative symptoms to impairments in social functioning. Both symptomatic and diagnostic baseline depression was significantly associated with decreased likelihood of remission from CHR status; however depression did not differentially distinguish persistent CHR status from transition to psychosis at follow-up. These findings suggest that depressed mood may function as a marker of poor prognosis in CHR, yet effective treatment of depression within this population can yield improvements in symptoms and functioning

    Psychosocial Capacity Building in Response to Cascading Disasters: A Culturally Informed Approach

    Get PDF
    The dominant paradigm guiding mental health professionals responding to major disasters is the field of \u27disaster mental health\u27, which historically focused more on psychological factors than social factors, privileging individual over collective interventions. However, resilience to complex events is a result of multiple drivers, such as social networks and local culture, that must be considered together in the assessment and planning process. This paper adopts a multi-disciplinary perspective for disaster response, applying a social-ecological approach to disaster risk reduction which has been developed through practice and a review of the literature. In particular, we investigated how psychosocial healing, collective efficacy and social justice as intertwined aspects of the recovery process may inhibit the escalation of cascading disasters. The article argues that psychosocial capacity building can be used in disaster preparation as well as to respond to cascading events, as the escalation of secondary emergencies caused by the loss of vital services can heavily influence collective behaviors, and hinder the response capacity of emergency services. Our research suggests that adopting a multi-systemic approach, drawing on local cultural practices, can deepen the capacity of local people to take control over their own process of healing and psychosocial restoration, enhancing a sustainable recovery process. The conclusions suggest some possible applications for responders, utilizing groups and activities, and raise questions for researchers in the field

    Preserving the Chesapeake: Law, Ecology, and the Bay

    Get PDF
    This event was co-sponsored by the Merhige Center for Environmental Studies, the Allen Chair of Law, the Virginia State Bar, and the Miller Center of Public Affairs. The “Historical Background” session, held from 9:30 - 10:30 a.m., was presented by the Hon. Governor Gerald L. Baliles, Director of the Miller Center of Public Affairs and 65th Governor of the Commonwealth of Virginia; Gerald McCarthy, Executive Director of the Virginia Environmental Endowment; and Russell W. Baxter, Deputy Director of the Virginia Department of Conservation and Recreation. Rodney A. Smolla, Dean of the University of Richmond School of Law, served as moderator. The “Current State of the Bay” session, held on Friday, October 20, 2006 from 10:45 - 11:45 a.m., was presented by Jonathan Z. Cannon, Director of the Center for Environmental and Land Use Law at the University of Virginia School of Law; Erin Ryan, of the Marshall-Wythe School of Law at the College of William and Mary; and Richard Batiuk, Associate Director for Science of the Chesapeake Bay Program Office, United States Environmental Protection Agency. Joel Eisen, University of Richmond School of Law, served as moderator. The Keynote was given from 11:45 a.m. - 1:15 p.m. by L. Preston Bryant, Secretary of Natural Resources of the Commonwealth of Virginia. The “Regulatory Efforts” session, held 1:15-2:15 p.m., was presented by Kathy R. Frahm, Director of the Division of Policy at the Virginia Department of Environmental Quality; Joseph J. Tannery, Virginia Staff Attorney for the Chesapeake Bay Foundation; David E. Evans, Partner at McGuireWoods LLP; and Mark Smith, Environmental Scientist with the Water Protection Division, U.S. Environmental Protection Agency. The “Future and Solutions” session, held from 2:30-3:45 p.m., was presented by Nikki Rovner, Deputy Secretary of Natural Resources for the Commonwealth of Virginia; Timothy G. Hayes, Partner at Hunton & Williams LLP; Clyde Wilbur, Principal of Greeley & Hanson; and Alexandra Dunn, General Counsel for the National Association of Clean Water Agencies. Carl W. Tobias, Williams Professor of Law University of Richmond School of Law, served as moderator

    Systematic analysis of the contributions of stochastic voltage gated channels to neuronal noise

    Get PDF
    Electrical signaling in neurons is mediated by the opening and closing of large numbers of individual ion channels. The ion channels' state transitions are stochastic and introduce fluctuations in the macroscopic current through ion channel populations. This creates an unavoidable source of intrinsic electrical noise for the neuron, leading to fluctuations in the membrane potential and spontaneous spikes. While this effect is well known, the impact of channel noise on single neuron dynamics remains poorly understood. Most results are based on numerical simulations. There is no agreement, even in theoretical studies, on which ion channel type is the dominant noise source, nor how inclusion of additional ion channel types affects voltage noise. Here we describe a framework to calculate voltage noise directly from an arbitrary set of ion channel models, and discuss how this can be use to estimate spontaneous spike rates

    Urban Biodiversity and Landscape Ecology: Patterns, Processes and Planning

    Get PDF
    Effective planning for biodiversity in cities and towns is increasingly important as urban areas and their human populations grow, both to achieve conservation goals and because ecological communities support services on which humans depend. Landscape ecology provides important frameworks for understanding and conserving urban biodiversity both within cities and considering whole cities in their regional context, and has played an important role in the development of a substantial and expanding body of knowledge about urban landscapes and communities. Characteristics of the whole city including size, overall amount of green space, age and regional context are important considerations for understanding and planning for biotic assemblages at the scale of entire cities, but have received relatively little research attention. Studies of biodiversity within cities are more abundant and show that longstanding principles regarding how patch size, configuration and composition influence biodiversity apply to urban areas as they do in other habitats. However, the fine spatial scales at which urban areas are fragmented and the altered temporal dynamics compared to non-urban areas indicate a need to apply hierarchical multi-scalar landscape ecology models to urban environments. Transferring results from landscape-scale urban biodiversity research into planning remains challenging, not least because of the requirements for urban green space to provide multiple functions. An increasing array of tools is available to meet this challenge and increasingly requires ecologists to work with planners to address biodiversity challenges. Biodiversity conservation and enhancement is just one strand in urban planning, but is increasingly important in a rapidly urbanising world
    • 

    corecore