Closing the gap between existing large-area imaging research and marine conservation needs.

Emerging technology has immense potential to increase the scale and efficiency of marine conservation. One such technology is large-area imaging (LAI), which relies on structure-from-motion photogrammetry to create composite products, including 3-dimensional (3-D) environmental models, that are larger in spatial extent than the individual images used to create them. Use of LAI has become widespread in certain fields of marine science, primarily to measure the 3D structure of benthic ecosystems and track change over time. However, the use of LAI in the field of marine conservation appears limited. We conducted a review of the coral reef literature on the use of LAI to identify research themes and regional trends in applications of this technology. We also surveyed 135 coral reef scientists and conservation practitioners to determine community familiarity with LAI, evaluate barriers practitioners face in using LAI, and identify applications of LAI believed to be most exciting or relevant to coral conservation. Adoption of LAI was limited primarily to researchers at institutions based in advanced economies and was applied infrequently to conservation, although conservation practitioners and survey respondents from emerging economies indicated they expect to use LAI in the future. Our results revealed disconnect between current LAI research topics and conservation priorities identified by practitioners, highlighting the need for more diverse, conservation-relevant research using LAI. We provide recommendations for how early adopters of LAI (typically Global North scientists from well-resourced institutions) can facilitate access to this conservation technology. These recommendations include developing training resources, creating partnerships for data storage and analysis, publishing standard operating procedures for LAI workflows, standardizing methods, developing tools for efficient data extraction from LAI products, and conducting conservation-relevant research using LAI.

Reducción de la brecha entre la investigación actual de imágenes de gran superficie y las necesidades de la conservación marina Resumen Las nuevas tecnologías tienen un enorme potencial para aumentar la escala y la eficiencia de la conservación marina. Una de ellas son las imágenes de gran superficie (IGS), que se basan en la fotogrametría de estructura a partir del movimiento para crear productos compuestos, incluidos modelos ambientales tridimensionales (3D), cuya extensión espacial es mayor que la de las imágenes individuales utilizadas para crearlos. El uso de las IGS se ha generalizado en determinados campos de las ciencias marinas, principalmente para medir la estructura tridimensional de los ecosistemas bentónicos y realizar un seguimiento de los cambios a lo largo del tiempo. Sin embargo, el uso de las IGS en el campo de la conservación marina parece limitado. Realizamos una revisión de la bibliografía sobre el uso de las IGS en los arrecifes de coral para identificar temas de investigación y tendencias regionales en las aplicaciones de esta tecnología. También encuestamos a 135 científicos de arrecifes de coral y profesionales de la conservación para determinar la familiaridad de la comunidad con las IGS, evaluar las barreras a las que se enfrentan los profesionales en el uso de las IGS e identificar sus aplicaciones consideradas como las más interesantes o relevantes para la conservación del coral. La adopción de las IGS se limitó principalmente a los investigadores de las instituciones con sede en las economías avanzadas y se aplicó con poca frecuencia a la conservación, aunque los profesionales de la conservación y los encuestados de las economías emergentes indicaron que esperan utilizar las IGS en el futuro. Nuestros resultados revelaron una desconexión entre los actuales temas de investigación de las IGS y las prioridades de conservación identificadas por los profesionales, lo que subraya la necesidad de una investigación más diversa y relevante para la conservación mediante el uso de las IGS.

Review of hyperdispersal in wildlife translocations.

Species translocation is a common tool to reverse biodiversity loss, but it has a high failure rate. One factor that contributes to failure is postrelease hyperdispersal, which we define as the long-distance movement of individuals resulting in their failure to contribute to population establishment. We reviewed reported incidences of hyperdispersal and compared rates of hyperdispersal among taxa, population demographics, release cohorts, and success of mitigation techniques. Of 151 conservation translocations (reinforcements and reintroductions) in which animals were tracked, hyperdispersal was confirmed in 52.1% of programs. The prevalence of hyperdispersal (percentage of studies) was relatively consistent across taxa (42.9-60%), but hyperdispersal rates in birds were likely underestimated because 76.9% of bird translocations showed incidences in which birds could not be located after release, but hyperdispersal was unable to be confirmed. Eutherians exhibited a higher average incidence of hyperdispersal (percentage of hyperdispersing individuals in a cohort) of 20.2% than birds, reptiles, and marsupials (10.4%, 15.7%, and 10.3%, respectively). No significant trends were observed for sex, source population, or translocation type, but there were nonsignificant trends for males to hyperdisperse more than females and for higher incidences of hyperdispersal in reinforcements relative to reintroduction programs. Mitigation techniques included temporary confinement, supplementation of resources, and releasing animals in social groups, but only half of studies examining mitigation techniques found them useful. Hyperdispersal incidence was variable within taxa, and we advise against forming translocations strategies based on results from other species. Hyperdispersal is a significant welfare, economic, and conservation issue in translocations, and we suggest definitions, reporting, and experimental strategies to address it.

Revisión de la hiperdispersión en las reubicaciones de fauna Resumen La reubicación de especies se usa muy seguido como herramienta para revertir la pérdida de la biodiversidad a pesar de tener una tasa elevada de fracaso. Un factor que contribuye a este fracaso es la hiperdispersión posterior a la liberación, la cual definimos como el movimiento de larga distancia de los individuos que resulta en su fracaso para contribuir al establecimiento de la población. Revisamos las incidencias reportadas de la hiperdispersión y comparamos las tasas de hiperdispersión entre los taxones, las poblaciones, demografías, grupos de edad liberados y el éxito de las técnicas de mitigación. Confirmamos la hiperdispersión en 52.1% de 151 reubicaciones de conservación (reforzamiento y reintroducciones) en las cuales se rastreó a los animales. La prevalencia de la hiperdispersión (el porcentaje de estudios) tuvo una coherencia relativa en todos los taxones (42.9-60%), aunque probablemente se subestimaron las tasas de hiperdispersión de las aves porque el 76.9% de sus reubicaciones mostraron incidencias en las que no se pudieron ubicar a los individuos después de la liberación, pero tampoco se pudo confirmar la hiperdispersión. Los euterios exhibieron un promedio de incidencia de hiperdispersión (porcentaje de individuos con hiperdispersión dentro de un grupo de edad) del 20.2%, mayor que el de las aves, reptiles y marsupiales (10.4%, 15.7% y 10.3% respectivamente). No observamos tendencias significativas para el sexo, la población original o el tipo de reubicación, aunque sí hubo tendencias no significativas de mayor hiperdispersión en los machos que en las hembras y de mayor incidencia de hiperdispersión en los reforzamientos en relación con los programas de reintroducción. Las técnicas de mitigación incluyeron el confinamiento temporal, el suplemento de recursos y la liberación de animales en grupos sociales, pero sólo la mitad de los estudios que examinaban estas técnicas las encontraron útiles. La incidencia de la hiperdispersión varió en cada taxón, por lo que aconsejamos no estructurar las estrategias de reubicación con base en los resultados de otras especies. La hiperdispersión es un tema importante para el bienestar, la conservación y la economía de las reubicaciones y sugerimos estrategias de definición, reporte y experimentación para abordarla.

Evaluating the impact of caribou habitat restoration on predator and prey movement.

Fragmentation of the boreal forest by linear features, including seismic lines, has destabilized predator-prey dynamics, resulting in the decline of woodland caribou (Rangifer tarandus caribou) populations. Restoration of human-altered habitat has therefore been identified as a critical management tool for achieving self-sustaining woodland caribou populations. However, only recently has testing of the response of caribou and other wildlife to restoration activities been conducted. Early work has centered around assessing changes in wildlife use of restored seismic lines. We evaluated whether restoration reduces the movement rates of predators and their associated prey, which is expected to decrease predator hunting efficiency and ultimately reduce caribou mortality. We developed a new method for using cameras to measure fine-scale movement by measuring speed as animals traveled between cameras in an array. We used our method to quantify speed of caribou, moose (Alces alces), bears (Ursus americanus), and wolves (Canis lupus) on treated (restored) and untreated seismic lines. Restoration treatments reduced travel speeds along seismic lines of wolves by 1.38 km/h, bears by 0.55 km/h, and caribou by 1.57 km/h, but did not reduce moose travel speeds. Reduced predator and caribou speeds on treated seismic lines are predicted to decrease encounter rates between predators and caribou and thus lower caribou kill rates. However, further work is needed to determine whether reduced movement rates result in reduced encounter rates with prey, and ultimately reduced caribou mortality.

La fragmentación del bosque boreal causado por los accidentes lineales, incluyendo a las líneas sísmicas, ha desestabilizado las dinámicas depredador-presa, lo que resulta en la declinación de las poblaciones de caribú (Rangifer tarandus caribou). Por esto, la restauración del hábitat con alteraciones antropogénicas ha sido identificada como una herramienta fundamental de gestión para obtener poblaciones autosuficientes de esta especie. Sin embargo, no es hasta hace poco que se ha analizado la respuesta del caribú y otras especies a las actividades de restauración; los primeros trabajos se centraban en analizar los cambios en el uso que les daban las especies a las líneas sísmicas restauradas. Evaluamos si la restauración reduce las tasas de movimiento de los depredadores y sus presas asociadas, las cuales se esperan disminuyan la eficiencia de caza de los depredadores y por último reduzcan la mortalidad del caribú. Desarrollamos un nuevo método para usar las cámaras para medir el movimiento detallado mediante la medición de la velocidad con la que los animales se trasladan a lo largo de una serie de cámaras. Usamos nuestro método para cuantificar la velocidad del caribú, alces (Alces alces), osos (Ursus americanus) y lobos (Canis lupus) en líneas sísmicas tratadas (restauradas) y no tratadas. Los tratamientos de restauración redujeron la velocidad de movimiento de los lobos (reducción de 1.38 km/hora), osos (0.55 km/hora) y caribú (1.57 km/hora), pero no afectaron la velocidad de movimiento de los alces. Se pronostica que la reducción en la velocidad de movimiento sobre las líneas sísmicas disminuye la proporción de encuentros entre el caribú y sus depredadores y, por lo tanto, reduce la proporción de muertes del caribú. Sin embargo, se necesita un análisis más profundo para determinar si la tasa reducida de movimiento resulta en una tasa reducida de encuentros con depredadores y si, por último, esto reduce la mortalidad del caribú.

Characterizing the landscape of movement to identify critical wildlife habitat and corridors.

Landscape planning that ensures the ecological integrity of ecosystems is critical in the face of rapid human-driven habitat conversion and development pressure. Wildlife tracking data provide unique and valuable information on animal distribution and location-specific behaviors that can serve to increase the efficacy of such planning. Given the spatiotemporal complexity inherent to animal movements, the interaction between movement behavior and a location is often oversimplified in commonly applied analyses of tracking data. We analyzed GPS-tracking-derived metrics of intensity of use, structural properties (based on network theory), and properties of the movement path (speed and directionality) with machine learning to define homogeneous spatial movement types. We applied our approach to a long-term tracking data set of over 130 African elephants (Loxodonta africana) in an area under pressure from infrastructure development. We identified 5 unique location-specific movement categories displayed by elephants, generally defined as high, medium, and low use intensity, and 2 types of connectivity corridors associated with fast and slow movements. High-use and slow-movement corridors were associated with similar landscape characteristics associated with productive areas near water, whereas low-use and fast corridors were characterized by areas of low productivity farther from water. By combining information on intensity of use, properties of movement paths, and structural aspects of movement across the landscape, our approach provides an explicit definition of the functional role of areas for movement across the landscape that we term the movescape. This combined, high-resolution information regarding wildlife space use offers mechanistic information that can improve landscape planning.

Caracterización del Paisaje de Movimiento para Identificar Hábitats y Corredores de Fauna Importantes Resumen La planeación de paisajes que asegura la integridad ecológica de los ecosistemas es muy importante de cara a la rápida conversión de hábitats llevada por la acción humana y la presión del desarrollo. Los datos de rastreo de fauna proporcionan información única y valiosa sobre la distribución animal y el comportamiento específico por localidad que puede servir para incrementar la eficiencia de dicha planeación. Dada la complejidad espaciotemporal inherente al movimiento animal, la interacción entre la conducta de movimiento y la ubicación con frecuencia se ve sobre simplificada en los análisis de información de rastreos aplicados comúnmente. Analizamos las medidas derivadas de rastreos por GPS de la intensidad de uso, las propiedades estructurales (basadas en la teoría de redes) y las propiedades de la vía de movimiento (velocidad y direccionalidad) con aprendizaje automatizado para definir los tipos de movimiento espacial homogéneo. Aplicamos nuestra estrategia a un conjunto de datos de rastreo a largo plazo de más de 130 elefantes africanos (Loxodonta africana) en un área bajo presión ocasionada por el desarrollo de infraestructura. Identificamos cinco categorías de movimiento específico por localidad exhibidas por los elefantes, definidas en términos generales como intensidad de uso alta, media y baja. También identificamos dos tipos de corredores de conectividad asociados con movimientos rápidos y lentos. Los corredores de intensidad de uso alta y movimiento lento estuvieron asociados con las características similares de paisaje asociadas a las áreas productivas cercanas a cuerpos de agua, mientras que los corredores de intensidad baja y movimiento rápido estuvieron caracterizados por áreas de baja productividad alejadas de los cuerpos de agua. Con la combinación de la información sobre la intensidad de uso, las propiedades de las vías de movimiento y los aspectos estructurales del movimiento a lo largo del paisaje, nuestra estrategia proporciona una definición explícita del papel funcional que tienen las áreas de movimiento en el paisaje, la cual denominamos paisaje de movimiento (movescape). Esta información combinada y de alta resolución con respecto al uso espacial por la fauna ofrece información mecánica que puede mejorar la planeación del paisaje.

Effects of body size on estimation of mammalian area requirements.

Accurately quantifying species' area requirements is a prerequisite for effective area-based conservation. This typically involves collecting tracking data on species of interest and then conducting home-range analyses. Problematically, autocorrelation in tracking data can result in space needs being severely underestimated. Based on the previous work, we hypothesized the magnitude of underestimation varies with body mass, a relationship that could have serious conservation implications. To evaluate this hypothesis for terrestrial mammals, we estimated home-range areas with global positioning system (GPS) locations from 757 individuals across 61 globally distributed mammalian species with body masses ranging from 0.4 to 4000 kg. We then applied block cross-validation to quantify bias in empirical home-range estimates. Area requirements of mammals <10 kg were underestimated by a mean approximately15%, and species weighing approximately100 kg were underestimated by approximately50% on average. Thus, we found area estimation was subject to autocorrelation-induced bias that was worse for large species. Combined with the fact that extinction risk increases as body mass increases, the allometric scaling of bias we observed suggests the most threatened species are also likely to be those with the least accurate home-range estimates. As a correction, we tested whether data thinning or autocorrelation-informed home-range estimation minimized the scaling effect of autocorrelation on area estimates. Data thinning required an approximately93% data loss to achieve statistical independence with 95% confidence and was, therefore, not a viable solution. In contrast, autocorrelation-informed home-range estimation resulted in consistently accurate estimates irrespective of mass. When relating body mass to home range size, we detected that correcting for autocorrelation resulted in a scaling exponent significantly >1, meaning the scaling of the relationship changed substantially at the upper end of the mass spectrum.

Efectos del Tamaño Corporal sobre la Estimación de los Requerimientos de Área de Mamíferos Resumen La cuantificación precisa de los requerimientos de área de una especie es un prerrequisito para que la conservación basada en áreas sea efectiva. Esto comúnmente implica la recolección de datos de rastreo de la especie de interés para después realizar análisis de la distribución local. De manera problemática, la autocorrelación en los datos de rastreo puede resultar en una subestimación grave de las necesidades de espacio. Con base en trabajos previos, formulamos una hipótesis en la que supusimos que la magnitud de la subestimación varía con la masa corporal, una relación que podría tener implicaciones serias para la conservación. Para probar esta hipótesis en mamíferos terrestres, estimamos las áreas de distribución local con las ubicaciones en GPS de 757 individuos de 61 especies de mamíferos distribuidas mundialmente con una masa corporal entre 0.4 y 4,000 kg. Después aplicamos una validación cruzada en bloque para cuantificar el sesgo en estimaciones empíricas de la distribución local. Los requerimientos de área de los mamíferos <10 kg fueron subestimados por una media ∼15% y las especies con una masa ∼100 kg fueron subestimadas en ∼50% en promedio. Por lo tanto, encontramos que la estimación del área estaba sujeta al sesgo inducido por la autocorrelación, el cual era peor para las especies de talla grande. En combinación con el hecho de que el riesgo de extinción incrementa conforme aumenta la masa corporal, el escalamiento alométrico del sesgo que observamos sugiere que la mayoría de las especies amenazadas también tienen la probabilidad de ser aquellas especies con las estimaciones de distribución local menos acertadas. Como corrección, probamos si la reducción de datos o la estimación de la distribución local informada por la autocorrelación minimizan el efecto de escalamiento que tiene la autocorrelación sobre las estimaciones de área. La reducción de datos requirió una pérdida de datos del ∼93% para lograr la independencia estadística con un 95% de confianza y por lo tanto no fue una solución viable. Al contrario, la estimación de la distribución local informada por la autocorrelación resultó en estimaciones constantemente precisas sin importar la masa corporal. Cuando relacionamos la masa corporal con el tamaño de la distribución local, detectamos que la corrección de la autocorrelación resultó en un exponente de escalamiento significativamente >1, lo que significa que el escalamiento de la relación cambió sustancialmente en el extremo superior del espectro de la masa corporal.

Habitat-tree protection concepts over 200 years.

The protection and sustainable management of habitat trees is an integral part of modern forest nature conservation concepts such as retention forestry. Bats, cavity-nesting birds, arboreal marsupials, and many different saproxylic species depend on habitat trees and their great variety of microhabitats and old-growth characteristics. With a focus on insights from temperate forests, we traced the development of habitat-tree protection over 200 years. The idea was first conceptualized by foresters and natural scientists in the early 19th century. At that time, utilitarian conservation aimed to protect cavity trees that provided roosts and nesting holes for insectivorous bats and birds. By the second half of the 19th century, habitat-tree protection was well known to foresters and was occasionally implemented. Knowledge of the protection of large old trees, a special kind of habitat tree, for sociocultural and aesthetic reasons developed similarly. But, many foresters of that time and in the following decades fundamentally rejected protection of habitat trees for economic reasons. Beginning in the 1970s, forest conservation and integrative forest management became increasingly important issues worldwide. Since then, the protection of habitat trees has been implemented on a large scale. Long-term views on the development of conservation concepts are important to inform the implementation of conservation today. In particular, historical analyses of conservation concepts allow the testing of long-term conservation outcomes and make it possible to study the resilience of conservation approaches to changing social or ecological conditions. We encourage all conservation ecologists to assess the practical and conceptual impact of the initial ideas that led to modern conservation concepts in terms of long-term biodiversity conservation.

Conceptos de Protección de Árboles Hábitat en los Últimos 200 Años Resumen La protección y el manejo sustentable de los árboles hábitat son una parte integral de los conceptos modernos de conservación de la naturaleza del bosque, conceptos como la silvicultura de retención. Los murciélagos, las aves que anidan en cavidades, los marsupiales arbóreos y muchas especies saproxílicas diferentes dependen de los árboles hábitat y su gran variedad de microhábitats y características de bosque maduro. Rastreamos el desarrollo de la protección de árboles hábitat en los últimos 200 años con un enfoque de conocimiento a partir de los bosques templados. La idea primero la conceptualizaron silvicultores y científicos naturales en el siglo XIX. En aquel tiempo, la conservación utilitarista buscaba proteger los árboles con cavidades que proporcionaban perchas y agujeros para anidar a los murciélagos y las aves insectívoras. Para la segunda mitad del siglo XIX, la protección de los árboles hábitat era muy conocida por los silvicultores y ocasionalmente la implementaban. El conocimiento de la protección de los grandes árboles maduros, un tipo especial de árbol hábitat, por razones socioculturales y estéticas tuvieron un desarrollo similar a la protección. Aún así, muchos de los silvicultores de esa época y de las décadas subsecuentes fundamentalmente rechazaron la protección de los árboles hábitat por razones económicas. A principios de la década de 1970, la conservación de los bosques y el manejo integrativo de los bosques se convirtieron en temas cada vez más importantes en todo el mundo. Desde entonces, la protección de los árboles hábitat se ha implementado a gran escala. Las perspectivas a largo plazo sobre el desarrollo de los conceptos de conservación son de importancia para informar la implementación de la conservación hoy en día. Particularmente, los análisis históricos sobre los conceptos de conservación permiten el ensayo de resultados de conservación a largo plazo y posibilitan el estudio de la resiliencia de las estrategias de conservación ante las cambiantes condiciones ecológicas y sociales. Alentamos a todos los ecologistas de la conservación a evaluar el impacto práctico y conceptual de las ideas iniciales que derivaron en los conceptos modernos de conservación en términos de la conservación a largo plazo de la biodiversidad.

Impacts of tropical forest disturbance on species vital rates.

Tropical forests are experiencing enormous threats from deforestation and habitat degradation. Much knowledge of the impacts of these land-use changes on tropical species comes from studies examining patterns of richness and abundance. Demographic vital rates (survival, reproduction, and movement) can also be affected by land-use change in a way that increases species vulnerability to extirpation, but in many cases these impacts may not be manifested in short-term changes in abundance or species richness. We conducted a literature review to assess current knowledge and research effort concerning how land-use change affects species vital rates in tropical forest vertebrates. We found a general paucity of empirical research on demography across taxa and regions, with some biases toward mammals and birds and land-use transitions, including fragmentation and agriculture. There is also considerable between-species variation in demographic responses to land-use change, which could reflect trait-based differences in species sensitivity, complex context dependencies (e.g., between-region variation), or inconsistency in methods used in studies. Efforts to improve understanding of anthropogenic impacts on species demography are underway, but there is a need for increased research effort to fill knowledge gaps in understudied tropical regions and taxa. The lack of information on demographic impacts of anthropogenic disturbance makes it difficult to draw definite conclusions about the magnitude of threats to tropical ecosystems under anthropogenic pressures. Thus, determining conservation priorities and improving conservation effectiveness remains a challenge.

The medical movement and Dr. Ismael Cosío Villegas. At half a century. / El movimiento médico y el doctor Ismael Cosío Villegas. A medio siglo.

In 1964, medical residents and interns of the Mexican Republic decided to carry out a work stoppage that stretched over for several months. Several prominent doctors decided to join the causes that motivated the movement, among which Dr. Ismael Cosío Villegas, who at that moment was the director general of the Huipulco hospital for tuberculosis patients; his participation and dedication are historical, and his determination caused for his resignation to be demanded. His trajectory remains practically unknown by the medical community.

En 1964, los médicos residentes e internos de la República Mexicana decidieron realizar un paro de labores que se extendió por meses; varios médicos notables decidieron unirse a las causas que motivaron dicho movimiento, entre ellos el director general en ese momento del Sanatorio para Tuberculosos de Huipulco, el doctor Ismael Cosío Villegas, cuya participación y entrega es histórica. La determinación del doctor Cosío Villegas provocó que se le exigiera su renuncia. La comunidad médica aún se desconoce su trayectoria.

Electroencephalography as a post-stroke assessment method: An updated review. / Electroencefalografía como método de evaluación tras un ictus. Una revisión actualizada.

Given that stroke is currently a serious problem in the population, employing more reliable and objective techniques for determining diagnosis and prognosis is necessary in order to enable effective clinical decision-making. EEG is a simple, low-cost, non-invasive tool that can provide information about the changes occurring in the cerebral cortex during the recovery process after stroke. EEG provides data on the evolution of cortical activation patterns which can be used to establish a prognosis geared toward harnessing each patient's full potential. This strategy can be used to prevent compensation and maladaptive plasticity, redirect treatments, and develop new interventions that will let stroke patients reach their new maximum motor levels.

Minimum area requirements for an at-risk butterfly based on movement and demography.

Determining the minimum area required to sustain populations has a long history in theoretical and conservation biology. Correlative approaches are often used to estimate minimum area requirements (MARs) based on relationships between area and the population size required for persistence or between species' traits and distribution patterns across landscapes. Mechanistic approaches to estimating MAR facilitate prediction across space and time but are few. We used a mechanistic MAR model to determine the critical minimum patch size (CMP) for the Baltimore checkerspot butterfly (Euphydryas phaeton), a locally abundant species in decline along its southern range, and sister to several federally listed species. Our CMP is based on principles of diffusion, where individuals in smaller patches encounter edges and leave with higher probability than those in larger patches, potentially before reproducing. We estimated a CMP for the Baltimore checkerspot of 0.7-1.5 ha, in accordance with trait-based MAR estimates. The diffusion rate on which we based this CMP was broadly similar when estimated at the landscape scale (comparing flight path vs. capture-mark-recapture data), and the estimated population growth rate was consistent with observed site trends. Our mechanistic approach to estimating MAR is appropriate for species whose movement follows a correlated random walk and may be useful where landscape-scale distributions are difficult to assess, but demographic and movement data are obtainable from a single site or the literature. Just as simple estimates of lambda are often used to assess population viability, the principles of diffusion and CMP could provide a starting place for estimating MAR for conservation.

Evaluating multispecies landscape connectivity in a threatened tropical mammal community.

Habitat corridors are important tools for maintaining connectivity in increasingly fragmented landscapes, but generally they have been considered in single-species approaches. Corridors intended to facilitate the movement of multiple species could increase persistence of entire communities, but at the likely cost of being less efficient for any given species than a corridor intended specifically for that species. There have been few tests of the trade-offs between single- and multispecies corridor approaches. We assessed single-species and multispecies habitat corridors for 5 threatened mammal species in tropical forests of Borneo. We generated maps of the cost of movement across the landscape for each species based on the species' local abundance as estimated through hierarchical modeling of camera-trap data with biophysical and anthropogenic covariates. Elevation influenced local abundance of banded civets (Hemigalus derbyanus) and sun bears (Helarctos malayanus). Increased road density was associated with lower local abundance of Sunda clouded leopards (Neofelis diardi) and higher local abundance of sambar deer (Rusa unicolor). Pig-tailed macaque (Macaca nemestrina) local abundance was lower in recently logged areas. An all-species-combined connectivity scenario with least-cost paths and 1 km buffers generated total movement costs that were 27% and 23% higher for banded civets and clouded leopards, respectively, than the connectivity scenarios for those species individually. A carnivore multispecies connectivity scenario, however, increased movement cost by 2% for banded civets and clouded leopards. Likewise, an herbivore multispecies scenario provided more effective connectivity than the all-species-combined scenario for sambar and macaques. We suggest that multispecies habitat connectivity plans be tailored to groups of ecologically similar, disturbance-sensitive species to maximize their effectiveness.

Identifying impediments to long-distance mammal migrations.

In much of the world, the persistence of long-distance migrations by mammals is threatened by development. Even where human population density is relatively low, there are roads, fencing, and energy development that present barriers to animal movement. If we are to conserve species that rely on long-distance migration, then it is critical that we identify existing migration impediments. To delineate stopover sites associated with anthropogenic development, we applied Brownian bridge movement models to high-frequency locations of pronghorn (Antilocapra americana) in the Greater Yellowstone Ecosystem. We then used resource utilization functions to assess the threats to long-distance migration of pronghorn that were due to fences and highways. Migrating pronghorn avoided dense developments of natural gas fields. Highways with relatively high volumes of traffic and woven-wire sheep fence acted as complete barriers. At crossings with known migration bottlenecks, use of high-quality forage and shrub habitat by pronghorn as they approached the highway was lower than expected based on availability of those resources. In contrast, pronghorn consistently utilized high-quality forage close to the highway at crossings with no known migration bottlenecks. Our findings demonstrate the importance of minimizing development in migration corridors in the future and of mitigating existing pressure on migratory animals by removing barriers, reducing the development footprint, or installing crossing structures.

Balzac and human gait analysis.

INTRODUCTION: People have been interested in movement analysis in general, and gait analysis in particular, since ancient times. Aristotle, Hippocrates, Galen, Leonardo da Vinci and Honoré de Balzac all used observation to analyse the gait of human beings. The purpose of this study is to compare Honoré de Balzac's writings with a scientific analysis of human gait. SOURCES: Honoré de Balzac's Theory of walking and other works by that author referring to gait. DEVELOPMENT: Honoré de Balzac had an interest in gait analysis, as demonstrated by his descriptions of characters which often include references to their way of walking. He also wrote a treatise entitled Theory of walking (Théorie de la demarche) in which he employed his keen observation skills to define gait using a literary style. He stated that the walking process is divided into phases and listed the factors that influence gait, such as personality, mood, height, weight, profession and social class, and also provided a description of the correct way of walking. CONCLUSIONS: Balzac considered gait analysis to be very important and this is reflected in both his character descriptions and Theory of walking, his analytical observation of gait. In our own technology-dominated times, this serves as a reminder of the importance of observation.

Response variables for evaluation of the effectiveness of conservation corridors.

Many studies have evaluated effectiveness of corridors by measuring species presence in and movement through small structural corridors. However, few studies have assessed whether these response variables are adequate for assessing whether the conservation goals of the corridors have been achieved or considered the costs or lag times involved in measuring the response variables. We examined 4 response variables-presence of the focal species in the corridor, interpatch movement via the corridor, gene flow, and patch occupancy--with respect to 3 criteria--relevance to conservation goals, lag time (fewest generations at which a positive response to the corridor might be evident with a particular variable), and the cost of a study when applying a particular variable. The presence variable had the least relevance to conservation goals, no lag time advantage compared with interpatch movement, and only a moderate cost advantage over interpatch movement or gene flow. Movement of individual animals between patches was the most appropriate response variable for a corridor intended to provide seasonal migration, but it was not an appropriate response variable for corridor dwellers, and for passage species it was only moderately relevant to the goals of gene flow, demographic rescue, and recolonization. Response variables related to gene flow provided a good trade-off among cost, relevance to conservation goals, and lag time. Nonetheless, the lag time of 10-20 generations means that evaluation of conservation corridors cannot occur until a few decades after a corridor has been established. Response variables related to occupancy were most relevant to conservation goals, but the lag time and costs to detect corridor effects on occupancy were much greater than the lag time and costs to detect corridor effects on gene flow.

Wildlife connectivity approaches and best practices in U.S. state wildlife action plans.

As habitat loss and fragmentation threaten biodiversity on large geographic scales, creating and maintaining connectivity of wildlife populations is an increasingly common conservation objective. To assess the progress and success of large-scale connectivity planning, conservation researchers need a set of plans that cover large geographic areas and can be analyzed as a single data set. The state wildlife action plans (SWAPs) fulfill these requirements. We examined 50 SWAPs to determine the extent to which wildlife connectivity planning, via linkages, is emphasized nationally. We defined linkage as connective land that enables wildlife movement. For our content analysis, we identified and quantified 6 keywords and 7 content criteria that ranged in specificity and were related to linkages for wide-ranging terrestrial vertebrates and examined relations between content criteria and statewide data on focal wide-ranging species, spending, revenue, and conserved land. Our results reflect nationwide disparities in linkage conservation priorities and highlight the continued need for wildlife linkage planning. Only 30% or less of the 50 SWAPs fulfilled highly specific content criteria (e.g., identifying geographic areas for linkage placement or management). We found positive correlations between our content criteria and statewide data on percent conserved land, total focal species, and spending on parks and recreation. We supplemented our content analysis with interviews with 17 conservation professionals to gain specific information about state-specific context and future directions of linkage conservation. Based on our results, relevant literature, and interview responses, we suggest the following best practices for wildlife linkage conservation plans: collect ecologically meaningful background data; be specific; establish community-wide partnerships; and incorporate sociopolitical and socioeconomic information.

[Deep brain recording and length of surgery in stereotactic and functional neurosurgery for movement disorders]. / Registro cerebral profundo y tiempo quirúrgico en la neurocirugía estereotáctica funcional para trastornos del movimiento.

OBJECTIVE: Our objectives were to study the length of multi-unit recordings (MURs) of brain activity in 20 years of movement disorder neurosurgeries and to determine the number of times in which it was necessary for the teams using single-unit recording (SUR) to explore all the electrode tracks in the simultaneously recorded sites (SRS). MATERIAL AND METHOD: This was a retrospective descriptive statistical analysis of MUR length on 4,296 tracks in 952 surgeries. The exclusion criteria were: tracks with fewer than 5 recorded signals, tracks that had a signal length different from the habitual 2s, or there being unusual situations not related to the MUR, as well as the first 20 surgeries of each surgical target. This yielded a total of 3,448 tracks in 805 surgeries. We also determined the number of the total 952 surgeries in which all the tracks in the SURs of the SRS were explored. RESULTS: The mean and its confidence interval (P=.05) of time per MUR track were 5.49±0.16min in subthalamic nucleus surgery, 8.82±0.24min in the medial or internal globus pallidus) and 18.51±1.31min in the ventral intermediate nucleus of the thalamus. For the total sum of tracks per surgery, in 75% of cases the total time was less than 39min in subthalamic nucleus, almost 42min in the medial or internal globus pallidus and less than 1h and 17min in ventral intermediate nucleus of the thalamus. All the tracks in the SUR SRS were explored in only 4.2% of the surgeries. CONCLUSIONS: The impact of MUR on surgical time is acceptable for this guide in objective localization for surgical targets, without having to use several simultaneous electrodes (not all indispensable in most of the cases). Consequently, there is less risk for the patient.

Evaluation of the efficacy of deep brain stimulation in the surgical treatment of cervical dystonia.

OBJECTIVE: Deep brain stimulation (DBS) of the globus pallidus internus (GPi) is a promising therapeutic option for patients with medically refractory dystonia. We present the results after 1 year of DBS of the GPi in 4 patients with cervical dystonia. MATERIALS AND METHODS: Four patients with medically refractory cervical dystonia who underwent stereotactic pallidal DBS surgery between June 2010 and November 2011 were included in this retrospective study. Preoperative and postoperative evaluations at 3, 6 and 12 months after surgery were performed using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS). RESULTS: The 4 patients experienced a sustained improvement, with a mean TWSTRS reduction of 74.25%, at 12 months follow-up. Disability improved by 80.5% (mean) at 1 year follow-up. No stimulation-related side effects were reported. CONCLUSION: Pallidal DBS is a valid and effective second-line treatment for patients with cervical focal dystonia. Our results support its use in patients with an insufficient response to medical treatment.

[In-phase and out-of-phase single-shot magnetization-prepared gradient recalled echo: description and optimization of technique at 1.5 T]. / Secuencia de disparo único eco de gradiente en fase y fase opuesta con preparación de la magnetización: descripción y optimización de la técnica con equipo de 1,5 T.

PURPOSE: To implement in-phase and out-of-phase (IP/OP) techniques with Magnetization-Prepared Gradient Recalled Echo (MP-GRE) and to evaluate the feasibility and diagnostic image quality among pre and post-optimized MP-GRE sequences, including patients unable to cooperate with breath-hold requirements. MATERIALS AND METHODS: Institutional review board approval with waiver of informed consent was obtained for this HIPAA-compliant retrospective study. Two groups of patients were included in the study, before and after optimization of MP-GRE parameters, with seventy-three (24 noncooperative/49 cooperative) and sixty-four (22 noncooperative/42 cooperative) consecutive patients, respectively. The motion-insensitive sequence used in this study was a single-shot 2D MP-GRE. Two radiologists qualitatively evaluated the sequences to identify the presence of phase cancellation artifact in OP images and to determine image quality, extent of artifacts (respiratory ghosting, bounce-point artifact, spatial misregistration and pixel graininess) and lesion conspicuity on the various sequences. The ability to visually detect liver steatosis and fatty adrenal adenomas was evaluated. Qualitative analyses were compared using the Wilcoxon and Mann-Whitney tests. RESULTS: There were statistically significant differences between all MP-GRE sequences concerning phase cancellation artifact (P<.0001) which was present in MP-GRE OP sequences and negligible to absent in the pre (IP1) and post-optimized (IP2) MP-GRE IP sequences, respectively, in all patients. Bounce point artifacts were significantly more pronounced in MP-GRE IP1 (P<.0001). Spatial misregistration was slightly more prominent in noncooperative patients with MP-GRE IP2 (P=.0027). MP-GRE OP and MP-GRE IP2 showed significantly higher overall image quality (P<.0001). MP-GRE sequences subjectively identified hepatic steatosis (n=20) and adrenal adenomas (n=5) based on signal loss from IP to OP sequence. CONCLUSION: Single shot IP/OP MP-GRE is feasible and allows motion resistant imaging with adequate diagnostic image quality. This technique is able to provide IP and OP information in patients unable to suspend respiration.

Combined thalamic and pallidal deep brain stimulation in diabetic hemiballism/hemichorea.

Hemiballism/hemichorea (HH) is a hyperkinetic movement disorder observed mostly in older adults with cerebrovascular diseases. Although the symptoms improve without any treatment, lesioning or DBS (deep brain stimulation) may be rarely required to provide symptomatic relief for patients with severe involuntary movements. HH is a rare complication of uncontrolled diabetes. There are only a few reported cases of diabetic HH that have been surgically treated. Thus, herein, we have reported the case of a 75-year-old female with type-II diabetes mellitus that presented with disabling involuntary limb movements of the left side, despite being treated conservatively for six months. DBS targeting the globus pallidus internus (GPi) and ventral intermediate (Vim) thalamic nucleus was performed. Complete resolution of symptoms was achieved with a combined stimulation of the thalamic Vim nucleus (at 1.7 mA) and GPi (at 2.4 mA). The combined stimulation of the Vim nucleus and GPi effectively resolved the diabetes-induced HH symptoms in our patient. Thus, although certain conclusions cannot be drawn due to the rarity of the surgically treated patients with HH, the combined stimulation is a novel treatment option for resistant HH.

Trends in Parkinson's mortality in Mexico 2000-2020.

OBJECTIVE: To describe the recent trends in Parkinson's disease mortality in Mexico during 2000-2020. METHOD: The adjusted mortality rate per 100,000 inhabitants was calculated using the direct method and the world standard population. Trend analysis was performed with the Joinpoint software. RESULTS: The average mortality rate was 1.26/100,000 inhabitants (SD: 0.09), and males showed higher mortality than females (M/F ratio=1.60). Older individuals ≥70 years old showed higher mortality rates than the rest of the age groups. During the period of study, a significant increase in mortality was observed from 2000 to 2005, while from 2005 to 2020 no significant trend was observed in all the studied groups. CONCLUSIONS: In Mexico, males and older individuals showed the highest mortality rates. The socioeconomic regions with high levels of wellness showed the highest mortality rates levels. Parkinson's mortality rate has remained constant since 2005 in Mexico.