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1.
Conserv Biol ; 38(3): e14285, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38686632

RESUMO

Most protected area impact research that uses counterfactuals draws heavily on quantitative methods, data, and knowledge types, making it valuable in producing generalizations but limited in temporal scope, historical detail, and habitat diversity and coverage of ecosystem services. We devised a methodological pluralistic approach, which supports social science qualitative methods, narratives, mixed methods, and interdisciplinarity, to fully unlock the potential of counterfactuals in ensuring a place-based and detailed understanding of the socioecological context and impacts of protected areas. We applied this approach to derive possible counterfactual conditions for the impact of a montane protected area on 40 years of vegetation change in the Cape Floristic Region-a global biodiversity hotspot and UNESCO World Heritage Site in South Africa. We incorporated diverse methods, knowledge, and information sources, drawing on before-after protected area comparisons for inside and outside the protected area. A significant increase in shrubland vegetation (17-30%) was observed and attributed primarily to a decline in frequent burning for grazing. This also occurred outside the protected area and was driven by socioeconomic drivers and not by concerns over biodiversity conservation or land degradation. Had the protected area not been established the area would have seen intensification of cultivation and increased road networks, buildings, and water storage in dams. Our approach increased historical temporal coverage of socioecological change and contextualized assumptions around causality. Protected area impact evaluation should reengage in place-based research that fully incorporates pluralism in methodologies for constructing counterfactuals in a way that builds regional and global understanding from the local level upward. We devised 10 key principles for deriving counterfactuals grounded in methodological pluralism, covering aspects of collaboration, cocreation, inter- and transdisciplinarity, diverse values and lived experiences, multiple knowledge types, multiple possible causal mechanisms, social science qualitative methods, perceptions, perspectives, and narratives.


Importancia del pluralismo metodológico en la derivación de situaciones contrafactuales para la conservación basada en evidencias Resumen La mayoría de las investigaciones sobre el impacto de las áreas protegidas que usan situaciones contrafactuales se basan en gran medida en métodos cuantitativos, datos y tipos de conocimiento, por lo que son muy valiosas para producir generalizaciones, pero limitadas en el enfoque temporal, el detalle histórico y la diversidad de hábitats y cobertura de los servicios ambientales. Diseñamos una estrategia metodológica pluralista, la cual apoya los métodos cualitativos de las ciencias sociales, narrativas, métodos mixtos e interdisciplinarios para utilizar por completo el potencial de las situaciones contrafactuales para asegurar un conocimiento detallado y basado en el lugar del contexto socio ecológico y el impacto de las áreas protegidas. Aplicamos esta estrategia para derivar las posibles condiciones contrafactuales del impacto de un área protegida montañosa sobre 40 años de cambio de vegetación en el reino florístico del Cabo ­ un punto caliente de biodiversidad y Sitio de Patrimonio Mundial de la UNESCO en Sudáfrica. Incorporamos varios métodos, conocimientos y fuentes de información a partir de las comparaciones antes­después dentro y fuera del área protegida. Observamos un incremento significativo en la vegetación del matorral (17­30%), el cual atribuimos principalmente en la disminución de la quema frecuente para el pastoreo. Esto también ocurrió fuera del área protegida y fue causado por factores socioeconómicos y no por preocupación por la conservación de la biodiversidad o por la degradación del suelo. De no haberse establecido el área protegida, la zona habría sufrido una intensificación de cultivos y un incremento de carreteras, edificios y almacenamiento de agua en presas. Nuestra estrategia incrementó la cobertura histórica temporal del cambio socio­ecológico y contextualizó las suposiciones sobre la causalidad. La evaluación del impacto del área protegida debe volver a la investigación basada en el lugar que incorpora de lleno el pluralismo en la metodología para construir situaciones contrafactuales de una forma que genere conocimiento regional y global a partir del nivel local y hacia arriba. Diseñamos diez principios clave para derivar las situaciones contrafactuales basados en el pluralismo metodológico, la cobertura de los aspectos de colaboración, creación conjunta, inter­ y transdisciplinariedad, valores diversos y experiencias vividas, varios tipos de conocimiento, diferentes mecanismos causales posibles, métodos cualitativos de las ciencias sociales, percepciones, perspectivas, historias y narrativas.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/métodos , África do Sul , Ecossistema
2.
Remote Sens Ecol Conserv ; 8(1): 57-71, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35873085

RESUMO

Non-forest ecosystems, dominated by shrubs, grasses and herbaceous plants, provide ecosystem services including carbon sequestration and forage for grazing, and are highly sensitive to climatic changes. Yet these ecosystems are poorly represented in remotely sensed biomass products and are undersampled by in situ monitoring. Current global change threats emphasize the need for new tools to capture biomass change in non-forest ecosystems at appropriate scales. Here we developed and deployed a new protocol for photogrammetric height using unoccupied aerial vehicle (UAV) images to test its capability for delivering standardized measurements of biomass across a globally distributed field experiment. We assessed whether canopy height inferred from UAV photogrammetry allows the prediction of aboveground biomass (AGB) across low-stature plant species by conducting 38 photogrammetric surveys over 741 harvested plots to sample 50 species. We found mean canopy height was strongly predictive of AGB across species, with a median adjusted R 2 of 0.87 (ranging from 0.46 to 0.99) and median prediction error from leave-one-out cross-validation of 3.9%. Biomass per-unit-of-height was similar within but different among, plant functional types. We found that photogrammetric reconstructions of canopy height were sensitive to wind speed but not sun elevation during surveys. We demonstrated that our photogrammetric approach produced generalizable measurements across growth forms and environmental settings and yielded accuracies as good as those obtained from in situ approaches. We demonstrate that using a standardized approach for UAV photogrammetry can deliver accurate AGB estimates across a wide range of dynamic and heterogeneous ecosystems. Many academic and land management institutions have the technical capacity to deploy these approaches over extents of 1-10 ha-1. Photogrammetric approaches could provide much-needed information required to calibrate and validate the vegetation models and satellite-derived biomass products that are essential to understand vulnerable and understudied non-forested ecosystems around the globe.

3.
Med Eng Phys ; 38(2): 187-91, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26776374

RESUMO

Measurements between anatomical landmarks on radiographs are useful for diagnosis and treatment planning in the orthopedic field. Direct measurement on single radiographic images, however, does not truly reflect spatial relationships, as depth information is lost. We used stereo images from a slot scanning X-ray machine to estimate coordinates of three-dimensional (3D) bony landmarks for femoral neck anteversion (FNA) measurement. A set of 7 landmarks consisting of the centre of the femoral head; the centre of the base of the femoral neck; the medial and lateral condyles; the medial and lateral posterior condyles; and finally the centre of the knee; were found to be identifiable and suitable for radiographic measurement. The reconstructed 3D coordinates were then used to define the 3D geometry of the anatomical axes required to estimate FNA. Stereophotogrammetric measurements on a sample of 30 dry right adult femurs were compared to reference values obtained using the Kingsley Olmstead method applied to photographic images. A strong positive correlation (0.998) was found and the mean ± standard deviation of the stereophotogrammetric approach (13.08 ± 6.87)° was comparable to that of the Kingsley Olmstead method (13.14 ± 6.88)°. Intra- and inter-observer reliability were high, with the lower bound of the 95% confidence interval above 0.98 for the intra-class correlation coefficient. The results merit further validation against three dimensional imaging technology such as computed tomography, to confirm stereophotogrammetry as a suitable alternative for FNA measurement.


Assuntos
Colo do Fêmur/anatomia & histologia , Colo do Fêmur/diagnóstico por imagem , Rotação , Tomografia Computadorizada por Raios X/métodos , Adulto , Humanos , Imageamento Tridimensional
4.
Psychol Rep ; 111(1): 157-64, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23045857

RESUMO

Traditional predictors of academic performance in college, such as measures of verbal and mathematical abilities [i.e., Scholastic Aptitude Test (SAT)] and academic achievement (i.e., high school GPA), often account for less than 25% of the variance in college performance, thus leaving a considerable amount of variance unexplained. The primary goal of this study was to examine developmental variables that may account for academic achievement beyond the traditional indices mentioned. Specifically, the relationships among four categories of life-skills and cumulative GPA were examined. A hierarchical multiple-regression analysis revealed that the four life-skills categories predicted an additional 9.4% of the variance in cumulative GPA beyond high school GPA and SAT scores. Of the four categories, physical fitness/health maintenance skills made a statistically significant, unique contribution to predicting cumulative GPA. Because of the exploratory nature of the current study, suggestions are made for conducting future research in light of the study's limitations.


Assuntos
Logro , Aptidão , Socialização , Adaptação Psicológica , Adolescente , Adulto , Testes de Aptidão/estatística & dados numéricos , Comunicação , Tomada de Decisões , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Relações Interpessoais , Masculino , Aptidão Física , Resolução de Problemas , Psicometria , Autoimagem , Adulto Jovem
5.
IEEE Trans Med Imaging ; 28(9): 1448-58, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19336298

RESUMO

Stereo-photogrammetry provides a low cost, easy to use, and noninvasive alternative to traditional facial anthropometry for the diagnosis of fetal alcohol syndrome (FAS). We describe such a system for use in obtaining 3-D facial information in infants. The infant is photographed using three high resolution digital cameras simultaneously while seated in a car seat. The subject's head is enclosed in a control frame during imaging. Technical system tests, namely control frame interpolation, camera calibration reliability, and camera synchronization delay assessments were performed. Direct and stereo-photogrammetric measurements of a doll were compared. Of 275 inter-landmark distances, 100% were within a 1.5 mm error range and 92.36% within a 1 mm error range when the two modalities were compared. Stereo-photogrammetry proved to be highly precise with submillimeter error in landmark placement for all landmarks on the doll. An intra-modality comparison of inter-landmark distances using two sets of images of five subjects showed the stereo-photogrammetric system to be highly reliable, with an average 72.25% of distances within a 1 mm error range. The system has potential for large scale screening and surveillance studies for FAS.


Assuntos
Antropometria , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Fotogrametria , Antropometria/instrumentação , Antropometria/métodos , Calibragem , Criança , Pré-Escolar , Desenho de Equipamento , Face/patologia , Feminino , Humanos , Imageamento Tridimensional , Lactente , Modelos Biológicos , Fotogrametria/instrumentação , Fotogrametria/métodos , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
J Sch Health ; 72(3): 107-14, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11962226

RESUMO

The Student Attitudes Toward School Safety Measures (SATSSM) instrument was developed as a new tool to assess high school students' attitudes towards school safety promotion methods. A theory-based pool of statements was scaled using Thurstone's equal appearing interval method by 186 student judges to yield a 30-item instrument. The draft version was operationalized into a 5-point, Likert scale format, using a new sample of 182 students. Exploratory factor analysis suggested three factors: mediation, surveillance, and searching methods. The SATSSM was reduced to six items for each scale with a five-item social desirability scale added, and piloted with 66 new students. Final administration of the SATSSM to 166 new students yielded scale and overall internal consistencies exceeding .80 with low interscale correlations. A simultaneously administered questionnaire measuring perceptions of school safety suggested students possessed increased awareness of school violence, but they believed improving school safety is beyond their school's control.


Assuntos
Atitude , Gestão da Segurança , Serviços de Saúde Escolar , Inquéritos e Questionários , Violência/prevenção & controle , Adolescente , Análise de Variância , Análise Fatorial , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sudeste dos Estados Unidos
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