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1.
Conserv Biol ; 37(6): e14150, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37461881

RESUMEN

Programs to protect biodiversity on private land are increasingly being used worldwide. To understand the efficacy of such programs, it is important to determine their impact: the difference between the program's outcome and what would have happened without the program. Typically, these programs are evaluated by estimating the average program-level impact, which readily allows comparisons between programs or regions, but masks important heterogeneity in impact across the individual conservation interventions. We used synthetic control design, statistical matching, and time-series data to estimate the impact of individual protected areas over time and combined individual-level impacts to estimate program-level impact with a meta-analytic approach. We applied the method to private protected areas governed by conservation covenants (legally binding on-title agreements to protect biodiversity) in the Goldfields region of Victoria, Australia using woody vegetation cover as our outcome variable. We compared our results with traditional approaches to estimating program-level impact based on a subset of covenants that were the same age. Our results showed an overall program-level impact of a 0.3-0.8% increase in woody vegetation cover per year. However, there was significant heterogeneity in the temporal pattern of impact for individual covenants, ranging from -4 to +7% change in woody vegetation cover per year. Results of our approach were consistent with results based on traditional approaches to estimating program-level impact. Our study provides a transparent and robust workflow to estimate individual and program-level impacts of private protected areas.


Evaluación del impacto del suelo privado de conservación con diseño de control sintético Resumen Los programas de protección de la biodiversidad en suelo privado se utilizan cada vez más en todo el mundo. Para entender la eficacia de estos programas, es importante determinar la diferencia entre el resultado del programa y lo que habría ocurrido sin él. Normalmente, estos programas se evalúan estimando el impacto medio a nivel de programa, lo que permite fácilmente las comparaciones entre programas o regiones, pero oculta una importante heterogeneidad en el impacto entre las intervenciones individuales de conservación. Utilizamos un diseño de control sintético, un emparejamiento estadístico y datos de series temporales para estimar el impacto de las áreas protegidas individuales a lo largo del tiempo y combinamos los impactos a nivel individual para estimar el impacto a nivel de programa con un enfoque meta-analítico. Aplicamos el método a áreas protegidas privadas regidas por acuerdos de conservación (acuerdos con vínculos jurídicos sobre la titularidad para proteger la biodiversidad) destinados a mejorar la cubierta vegetal leñosa en la región de Goldfields de Victoria, Australia. Comparamos nuestros resultados con los métodos tradicionales de estimación del impacto a nivel de programa basados en un subconjunto de pactos de la misma antigüedad. Nuestros resultados mostraron un impacto global a nivel de programa de un aumento del 0.3-0.8% de la cubierta vegetal leñosa al año. Sin embargo, hubo una heterogeneidad significativa en el patrón temporal del impacto para los pactos individuales, que osciló entre −4 y +7% de cambio en la cubierta vegetal leñosa por año. Los resultados de nuestra estrategia fueron consecuentes con los resultados basados en las estrategias tradicionales usadas para estimar el impacto a nivel de programa. Nuestro estudio proporciona un flujo de trabajo transparente y sólido para estimar el impacto individual a nivel de programa de las áreas protegidas privadas.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Conservación de los Recursos Naturales/métodos , Victoria , Ecosistema
2.
Environ Monit Assess ; 194(3): 185, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35157145

RESUMEN

Understanding the impact of management interventions on the environment over decadal and longer timeframes is urgently required. Longitudinal or large-scale studies with consistent methods are best practice, but more commonly, small datasets with differing methods are used to achieve larger coverage. Changes in methods and interpretation affect our ability to understand data trends through time or across space, so an ability to understand and adjust for such discrepancies between datasets is important for applied ecologists. Calibration or double sampling is the key to unlocking the value from disparate datasets, allowing us to account for the differences between datasets while acknowledging the uncertainties. We use a case study of livestock grazing impacts on riparian vegetation in southeastern Australia to develop a flexible and powerful approach to this problem. Using double sampling, we estimated changes in vegetation attributes over a 12-year period using a pseudo-quantitative visual method as the starting point, and the same technique plus point-intercept survey for the second round. The disparate nature of the datasets produced uncertain estimates of change over time, but accounting for this uncertainty explicitly is precisely the objective and highlights the need to look more closely at this very common problem in environmental management, as well as the potential benefits of the double sampling approach.


Asunto(s)
Monitoreo del Ambiente , Ganado , Animales , Calibración , Encuestas y Cuestionarios , Incertidumbre
3.
J Environ Manage ; 230: 94-101, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30273788

RESUMEN

Decision triggers are defined thresholds in the status of monitored variables that indicate when to undertake management, and avoid undesirable ecosystem change. Decision triggers are frequently recommended to conservation practitioners as a tool to facilitate evidence-based management practices, but there has been limited attention paid to how practitioners are integrating decision triggers into existing monitoring programs. We sought to understand whether conservation practitioners' use of decision triggers was influenced by the type of variables in their monitoring programs. We investigated this question using a practitioner-focused workshop involving a structured discussion and review of eight monitoring programs. Among our case studies, direct measures of biodiversity (e.g. native species) were more commonly monitored, but less likely to be linked to decision triggers (10% with triggers) than measures being used as surrogates (54% with triggers) for program objectives. This was because decision triggers were associated with management of threatening processes, which were often monitored as a surrogate for a biodiversity asset of interest. By contrast, direct measures of biodiversity were more commonly associated with informal decision processes that led to activities such as management reviews or external consultation. Workshop participants were in favor of including more formalized decision triggers in their programs, but were limited by incomplete ecological knowledge, lack of appropriately skilled staff, funding constraints, and/or uncertainty regarding intervention effectiveness. We recommend that practitioners consider including decision triggers for discussion activities (such as external consultation) in their programs as more than just early warning points for future interventions, particularly for direct measures. Decision triggers for discussions should be recognized as a critical feature of monitoring programs where information and operational limitations inhibit the use of decision triggers for interventions.


Asunto(s)
Biodiversidad , Toma de Decisiones , Monitoreo del Ambiente , Humanos , Incertidumbre
4.
Conserv Biol ; 31(6): 1418-1427, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28339135

RESUMEN

Many objectives motivate ecological restoration, including improving vegetation condition, increasing the range and abundance of threatened species, and improving species richness and diversity. Although models have been used to examine the outcomes of ecological restoration, few researchers have attempted to develop models to account for multiple, potentially competing objectives. We developed a combined state-and-transition, species-distribution model to predict the effects of restoration actions on vegetation condition and extent, bird diversity, and the distribution of several bird species in southeastern Australian woodlands. The actions reflected several management objectives. We then validated the models against an independent data set and investigated how the best management decision might change when objectives were valued differently. We also used model results to identify effective restoration options for vegetation and bird species under a constrained budget. In the examples we evaluated, no one action (improving vegetation condition and extent, increasing bird diversity, or increasing the probability of occurrence for threatened species) provided the best outcome across all objectives. In agricultural lands, the optimal management actions for promoting the occurrence of the Brown Treecreeper (Climacteris picumnus), an iconic threatened species, resulted in little improvement in the extent of the vegetation and a high probability of decreased vegetation condition. This result highlights that the best management action in any situation depends on how much the different objectives are valued. In our example scenario, no management or weed control were most likely to be the best management options to satisfy multiple restoration objectives. Our approach to exploring trade-offs in management outcomes through integrated modeling and structured decision-support approaches has wide application for situations in which trade-offs exist between competing conservation objectives.


Asunto(s)
Distribución Animal , Biodiversidad , Restauración y Remediación Ambiental/métodos , Bosques , Pájaros Cantores/fisiología , Animales , Conservación de los Recursos Naturales , Modelos Biológicos , Especificidad de la Especie , Victoria
5.
Sci Rep ; 7(1): 5568, 2017 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-28717182

RESUMEN

Cancer cells can have different patterns of exon usage of individual genes when compared to normal tissue, suggesting that alternative splicing may play a role in shaping the tumor phenotype. The discovery and identification of gene variants has increased dramatically with the introduction of RNA-sequencing technology, which enables whole transcriptome analysis of known, as well as novel isoforms. Here we report alternative splicing and transcriptional events among subtypes of invasive ductal carcinoma in The Cancer Genome Atlas (TCGA) Breast Invasive Carcinoma (BRCA) cohort. Alternative exon usage was widespread, and although common events were shared among three subtypes, ER+ HER2-, ER- HER2-, and HER2+, many events on the exon level were subtype specific. Additional RNA-seq analysis was carried out in an independent cohort of 43 ER+ HER2- and ER- HER2- primary breast tumors, confirming many of the exon events identified in the TCGA cohort. Alternative splicing and transcriptional events detected in five genes, MYO6, EPB41L1, TPD52, IQCG, and ACOX2 were validated by qRT-PCR in a third cohort of 40 ER+ HER2- and ER- HER2- patients, showing that these events were truly subtype specific.


Asunto(s)
Empalme Alternativo , Neoplasias de la Mama/genética , Carcinoma Ductal de Mama/genética , Perfilación de la Expresión Génica/métodos , Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Estudios de Cohortes , Bases de Datos Genéticas , Exones , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Análisis de Secuencia de ARN/métodos
6.
PLoS One ; 10(7): e0130153, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26177497

RESUMEN

BACKGROUND: Considerable resources are spent on habitat restoration across the globe to counter the impacts of habitat loss and degradation on wildlife populations. But, because of time and resourcing constraints on many conservation programs, the effectiveness of these habitat restoration programs in achieving their long-term goals of improving the population viability of particular wildlife species is rarely assessed and many restoration programs cannot demonstrate their effectiveness. Without such demonstration, and in particular demonstrating the causal relationships between habitat restoration actions and demographic responses of the target species, investments in restoration to achieve population outcomes are of uncertain value. APPROACH: Here, we describe an approach that builds on population data collected for a threatened Australian bird - the Grey-crowned Babbler Pomatostomus temporalis - to evaluate how effectively targeted habitat restoration work improves its viability. We built upon an extensive historical survey by conducting surveys 13 years later at 117 sites stratified by presence/absence of restoration works and by detection or not of birds in the first survey. Our performance metric was the number of individuals in a social group, which is both a measure of local abundance and directly related to breeding success. We employed an occupancy model to estimate the response of Grey-crowned Babbler social group size to the effects of time, restoration works, local habitat as measured by the density of large trees, and distance to the nearest other known group of babblers. RESULTS AND IMPLICATIONS: Babbler group size decreased over the survey period at sites without restoration works, but restoration works were effective in stemming declines where they were done. Restoration was responsible for a difference of about one bird per group of 3-5 individuals; this is an important effect on the reproductive success of the social group. Effectiveness of restoration works targeted at the Grey-crowned Babbler was only demonstrable by sampling through time and including control sites without restoration works. This work demonstrates that while calls for better monitoring of restoration are valid, scope exists to recover a signal of effectiveness from opportunistic retrospective analyses.


Asunto(s)
Conservación de los Recursos Naturales/estadística & datos numéricos , Ecosistema , Passeriformes , Animales , Encuestas y Cuestionarios , Victoria
7.
CBE Life Sci Educ ; 13(2): 297-310, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26086660

RESUMEN

The School for Science and Math at Vanderbilt (SSMV) is an innovative partnership program between a Research I private university and a large urban public school system. The SSMV was started in 2007 and currently has 101 students enrolled in the program, with a total of 60 students who have completed the 4-yr sequential program. Students attend the SSMV for one full day per week during the school year and 3-6 wk in the summers following their ninth- to 11th-grade years, with each grade of 26 students coming to the Vanderbilt campus on a separate day. The research-based curriculum focuses on guiding students through the process of learning to develop questions and hypotheses, designing projects and performing analyses, and communicating results of these projects. The SSMV program has elevated the learning outcomes of students as evidenced by increased achievement scores relative to a comparison group of students; has provided a rigorous research-based science, technology, engineering, and mathematics elective curriculum that culminates in a Summer research internship; has produced 27 Intel and Siemens semifinalists and regional finalists over the past 4 yr; and has supported the development of writing and communication skills resulting in regional and national oral presentations and publications in scientific journals.


Asunto(s)
Curriculum , Matemática/educación , Investigación/educación , Instituciones Académicas , Ciencia/educación , Estudiantes , Distinciones y Premios , Demografía , Evaluación Educacional , Ingeniería/educación , Femenino , Humanos , Internet , Masculino , Encuestas y Cuestionarios , Tecnología/educación , Tennessee
8.
Phys Rev Lett ; 90(21): 215501, 2003 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-12786563

RESUMEN

In this paper, we show that a noncrystalline but ordered smectic-like phase exists above the bulk-melting temperature (T(m)) at poly(n-alkyl acrylates)-air interface. The surface ordered phase is one monolayer thick and undergoes a sharp transition from order to disorder 10 degrees C above T(m) for n=22. The presence of a surface phase that does not exist in the bulk has important implications in the design of thermally responsive adhesives.

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