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1.
Rev. biol. trop ; 71(1)dic. 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1449521

RESUMEN

Introduction: Worldwide, expanding human activities continue to be a threat to many large-bodied species, including jaguars. As these activities continue, it is critical to understand how home range sizes will be impacted by human-modified landscapes. Objective: To evaluate the importance of protected and unprotected land on home-range size across their range. Methods: We used home range data from 117 jaguars in several habitat protection categories and human biome types. We used a Generalized Linear Mixed Model to test home range and spatial overlap with conservation categories and human biomes. Results: Most home-ranges were in Jaguar Conservation Units (62 %), followed by Protected Areas (21 %), Indigenous People's Lands (10 %) and Jaguar Movement Corridors (3 %), where 76 % of the jaguars lived inside one the first three conservation types. However, outside of conserved land, Rangeland, Cropland, Seminatural land and other human biomes were also important (24 % of the individuals). Jaguars in Rangeland, Cropland and Seminatural land had the largest home ranges. Conclusions: Although conservation land was dominant, human-impacted lands appear to play a considerable role in satisfying the spatial requirements of jaguars.


Introducción: A nivel mundial, la expansión de actividades humanas continúa teniendo un riesgo para muchas especies de cuerpo grande, tal como los jaguares. Conforme continúen estas actividades, es crucial entender el impacto de paisajes modificados sobre el tamaño de su territorio. Objetivo: Evaluar la importancia de terrenos protegidos y no protegidos sobre el tamaño de su territorio a lo largo de su rango. Métodos: Usamos datos de tamaño de los territorios de 117 jaguares en varias categorías de protección de hábitats y biomas humanos. Usamos un Modelo Mixto Lineal Generalizado para probar traslapes espaciales y de territorios con categorías de conservación y biomas humanos. Resultados: La mayoría de los territorios estaban en Unidades de Conservación de Jaguares (62 %), seguido por Áreas protegidas (21 %), Tierras de Pueblos Indígenas (10 %) y Corredores de Movimiento de Jaguares (3 %), en donde el 76 % de los jaguares vivían dentro de alguna de las primeras tres modalidades de conservación. Sin embargo, fuera de áreas protegidas, pastizales, tierras de cultivo, terrenos seminaturales y otros biomas humanos también fueron importantes (24 % de individuos). Jaguares en pastizales, tierras de cultivo, y terrenos seminaturales tuvieron territorios más grandes. Conclusiones: Aunque las áreas de conservación fueron dominantes, áreas con impacto humano parecieron jugar un rol considerable en satisfacer los requerimientos espaciales de los jaguares.

2.
PeerJ ; 11: e15491, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37283902

RESUMEN

Background: Agricultural and pastoral landscapes can provide important habitat for wildlife conservation, but sharing these landscapes with wildlife can create conflict that is costly and requires managing. Livestock predation is a good example of the challenges involving coexistence with wildlife across shared landscapes. Integrating new technology into agricultural practices could help minimize human-wildlife conflict. In this study, we used concepts from the fields of robotics (i.e., automated movement and adaptiveness) and agricultural practices (i.e., managing livestock risk to predation) to explore how integration of these concepts could aid the development of more effective predator deterrents. Methods: We used a colony of captive coyotes as a model system, and simulated predation events with meat baits inside and outside of protected zones. Inside the protected zones we used a remote-controlled vehicle with a state-of-the art, commercially available predator deterrent (i.e., Foxlight) mounted on the top and used this to test three treatments: (1) light only (i.e., without movement or adaptiveness), (2) predetermined movement (i.e., with movement and without adaptiveness), and (3) adaptive movement (i.e., with both movement and adaptiveness). We measured the time it took for coyotes to eat the baits and analyzed the data with a time-to-event survival strategy. Results: Survival of baits was consistently higher inside the protected zone, and the three movement treatments incrementally increased survival time over baseline except for the light only treatment in the nonprotected zone. Incorporating predetermined movement essentially doubled the efficacy of the light only treatment both inside and outside the protected zone. Incorporating adaptive movement exponentially increased survival time both inside and outside the protected zone. Our findings provide compelling evidence that incorporating existing robotics capabilities (predetermined and adaptive movement) could greatly enhance protection of agricultural resources and aid in the development of nonlethal tools for managing wildlife. Our findings also demonstrate the importance of marrying agricultural practices (e.g., spatial management of livestock at night) with new technology to improve the efficacy of wildlife deterrents.


Asunto(s)
Animales Salvajes , Coyotes , Animales , Humanos , Conservación de los Recursos Naturales , Agricultura , Ecosistema , Ganado
4.
Conserv Biol ; 37(3): e14057, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36661055

RESUMEN

Conservation biology is a mission-driven discipline that must navigate a new relationship between conservation and science. Because conservation is a social and political as well as an ecological project, conservation biologists must practice interdisciplinarity and collaboration. In a comparative study of 7 cases (Jaguars in the Chaco, Grevy's zebra in Kenya, Beekeeping in Tanzania, Andean cats in Argentina, Jaguars in Mexico, Lobster fishing, and Black bears in Mexico), we examined motivations for collaboration in conservation, who can collaborate in conservation, and how conservation professionals can work well together. In 5 case studies, successful conservation outcomes were prioritized over livelihood benefits. In the other 2 cases, livelihoods were prioritized. All case studies employed participatory approaches. There were multiple external actors, including local and Indigenous communities, nongovernmental organizations, agencies, regional and national governments, and international organizations, which enhanced conservation and wider sustainability outcomes. Key collaboration aspects considered across the case studies were time (mismatch between relationship building and project schedules), trust required for meaningful partnerships, tools employed, and transformative potential for people, nature, and the discipline of conservation biology. We developed guidelines for successful collaboration, including long-term commitment, knowledge integration, multiscalar and plural approaches, cultivation of trust, appropriate engagement, evaluation, supporting students, and efforts for transformation.


Facilitación de la conservación de la biodiversidad a través de colaboraciones para lograr resultados transformadores Resumen La biología de la conservación es una disciplina impulsada por sus objetivos que debe navegar una nueva relación entre la conservación y la ciencia. Dado que la conservación es un proyecto social y político así como ecológico, los biólogos de la conservación deben practicar la interdisciplinariedad y la colaboración. En un estudio comparativo de siete casos (jaguares en el Chaco, cebras de Grevy en Kenia, apicultura en Tanzania, gatos andinos en Argentina, jaguares en México, pesca de langosta, osos negros en México), analizamos las motivaciones para colaborar en la conservación, quién puede colaborar en la conservación y cómo los profesionales de la conservación pueden trabajar bien juntos. En cinco estudios de caso, se priorizaron los resultados satisfactorios de la conservación sobre los beneficios para los medios de subsistencia. En los otros 2 casos, se dio prioridad a los medios de sustento. Todos los estudios de caso emplearon enfoques participativos. Hubo múltiples actores externos, como comunidades locales e indígenas, organizaciones no gubernamentales, agencias, gobiernos regionales y nacionales y organizaciones internacionales, que mejoraron los resultados de conservación y sostenibilidad en general. Los aspectos clave de la colaboración considerados en los estudios de caso fueron el tiempo (desajuste entre el establecimiento de relaciones y los calendarios de los proyectos), la confianza necesaria para establecer colaboraciones significativas, las herramientas empleadas y el potencial transformador para las personas, la naturaleza y la disciplina de la biología de la conservación. Se elaboraron directrices para el éxito de la colaboración, como el compromiso a largo plazo, la integración de conocimientos, los enfoques multiescalares y plurales, el fomento de la confianza, la participación adecuada, la evaluación, el apoyo a los estudiantes y los esfuerzos de transformación. Facilitación de la conservación de la biodiversidad a través de colaboraciones para lograr resultados transformadores.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , México , Organizaciones , Kenia
5.
J Environ Manage ; 316: 115315, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35598453

RESUMEN

The global effort to protect megaherbivore populations is largely dependent on how human-wildlife conflict is identified, prioritized, and remedied. We examined the socio-ecological and landscape-scale factors determining spatial patterns of human-megaherbivore (Asian elephant Elephas maximus and gaur Bos gaurus) interactions across sixteen Forest Divisions in Tamil Nadu, India. Using a systematic grid-based design, we conducted questionnaire-based surveys of 1460 households at the human-wildlife interface adjacent to Protected Areas, Reserve Forest and Fringe Areas. We specifically collected information on elephant and gaur conflict incidents (e.g., human death/injuries, property damage, and crop-raiding), cropland type, extent of crop area and area lost to crop-raiding, from each household. We found that human-elephant conflict increased with percentage of crop cover, diversity of major and minor crops grown, proximity to water source, flat terrain, and lower rates of precipitation. Human-gaur conflict was greatest with a high diversity of major crops, proximity to water source, moderate precipitation, and more undulating terrain. We identified ca. 7900 km2 hotspot area of contiguous high-intensity elephant conflict. For gaur, we identified high-frequency conflict hotspot areas covering ca. 625 km2, which were patchily distributed, highly localised, and attributed mostly to the recent changing land-use patterns. Our findings will help policymakers and park managers in developing landscape-scale human-wildlife conflict mitigation plans in the identified conflict hotspots.


Asunto(s)
Conservación de los Recursos Naturales , Elefantes , Animales , Animales Salvajes , Bovinos , Productos Agrícolas , Humanos , India , Agua
6.
PLoS One ; 17(3): e0265440, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35303739

RESUMEN

Understanding the effect of anthropogenic disturbance, and its interaction with carnivores and their prey, is crucial to support the conservation of threatened carnivores, particularly in rapidly changing landscapes. Based on systematic camera-trap sampling of four protected areas in Riau Province of central Sumatra, we assessed the habitat occupancy and spatiotemporal overlap between people, potential carnivore prey, and four threatened species of medium-sized or large carnivores: Sumatran tigers (Panthera tigris sumatrae), Malayan sun bears (Helarctos malayanus), dholes (Cuon alpinus), and Sunda clouded leopards (Neofelis diardi). To assess spatial overlap of target species, we used single-species occupancy models and applied a Species Interaction Factor (SIF) to conditional two-species occupancy models. We also used kernel density estimation (KDE) to assess temporal overlap among these species. Our habitat use models showed that altitude (elevation) strongly influenced the occupancy of all large carnivores and potential prey species. Except for Sunda clouded leopards, the occurrence of large carnivore species was positively related to the spatial co-occurrence of humans (SIF > 1). In addition, we found that sun bears and dholes both exhibited high spatial overlap with tigers, and that sun bears alone exhibited high temporal overlap with people. Our findings contribute to an improved understanding of the contemporary ecology of carnivores and their prey in rapidly changing, southeast Asian landscapes. Such knowledge is important to the conservation and recovery of large carnivores in conservation hotspots that are increasingly dominated by humans across Sumatra, as well as globally.


Asunto(s)
Carnívoros , Tigres , Animales , Conservación de los Recursos Naturales , Ecosistema , Bosques , Humanos , Indonesia
7.
PLoS One ; 16(12): e0261171, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34905569

RESUMEN

The use of "belly scoring" can offer a novel, non-invasive objective management tool to gauge food intake between individuals, groups, and populations, and thus, population fitness. As food availability is increasingly affected by predation, ecological competition, climate change, habitat modification, and other human activities, an accurate belly scoring tool can facilitate comparisons among wildlife populations, serving as an early warning indicator of threats to wildlife population health and potential population collapse. In social species, belly scores can also be a tool to understand social behavior and ranking. We developed and applied the first rigorous quantitative photogrammetric methodology to measure belly scores of wild painted dogs (Lycaon pictus). Our methodology involves: (1) Rigorous selection of photographs of the dorso/lateral profile of individuals at a right angle to the camera, (2) photogrammetrically measuring belly chord length and "belly drop" in pixels, (3) adjusting belly chord length as a departure from a standardized leg angle, and (4) converting pixel measurements to ratios to eliminate the need to introduce distance from the camera. To highlight a practical application, this belly score method was applied to 631 suitable photographs of 15 painted dog packs that included 186 individuals, all collected between 2004-2015 from allopatric painted dog populations in and around Hwange (n = 462) and Mana Pools National Parks (n = 169) in Zimbabwe. Variation in mean belly scores exhibited a cyclical pattern throughout the year, corresponding to biologically significant patterns to include denning demand and prey availability. Our results show significant differences between belly scores of the two different populations we assessed, thus highlighting food stress in the Hwange population. In the face of growing direct and indirect anthropogenic disturbances, this standardised methodology can provide a rapid, species-specific non-invasive management tool that can be applied across studies to rapidly detect emergent threats.


Asunto(s)
Abdomen/anatomía & histología , Procesamiento de Imagen Asistido por Computador/métodos , Fotogrametría/métodos , Abdomen/diagnóstico por imagen , Animales , Animales Salvajes , Perros , Femenino , Masculino
8.
R Soc Open Sci ; 7(4): 190717, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32431857

RESUMEN

The persistent high deforestation rate and fragmentation of the Amazon forests are the main threats to their biodiversity. To anticipate and mitigate these threats, it is important to understand and predict how species respond to the rapidly changing landscape. The short-eared dog Atelocynus microtis is the only Amazon-endemic canid and one of the most understudied wild dogs worldwide. We investigated short-eared dog habitat associations on two spatial scales. First, we used the largest record database ever compiled for short-eared dogs in combination with species distribution models to map species habitat suitability, estimate its distribution range and predict shifts in species distribution in response to predicted deforestation across the entire Amazon (regional scale). Second, we used systematic camera trap surveys and occupancy models to investigate how forest cover and forest fragmentation affect the space use of this species in the Southern Brazilian Amazon (local scale). Species distribution models suggested that the short-eared dog potentially occurs over an extensive and continuous area, through most of the Amazon region south of the Amazon River. However, approximately 30% of the short-eared dog's current distribution is expected to be lost or suffer sharp declines in habitat suitability by 2027 (within three generations) due to forest loss. This proportion might reach 40% of the species distribution in unprotected areas and exceed 60% in some interfluves (i.e. portions of land separated by large rivers) of the Amazon basin. Our local-scale analysis indicated that the presence of forest positively affected short-eared dog space use, while the density of forest edges had a negative effect. Beyond shedding light on the ecology of the short-eared dog and refining its distribution range, our results stress that forest loss poses a serious threat to the conservation of the species in a short time frame. Hence, we propose a re-assessment of the short-eared dog's current IUCN Red List status (Near Threatened) based on findings presented here. Our study exemplifies how data can be integrated across sources and modelling procedures to improve our knowledge of relatively understudied species.

9.
Langmuir ; 36(24): 6728-6735, 2020 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-32453577

RESUMEN

An electroreflectance method to determine the electron transfer rate constant of a film of redox-active chromophores immobilized on an optically transparent electrode when the surface coverage of the film is very low (<0.1 monolayer) is described herein. The method, potential-modulated total internal reflection fluorescence (PM-TIRF) spectroscopy, is a fluorescence version of potential-modulated attenuated total reflection (PM-ATR) spectroscopy that is applicable when the immobilized chromophores are luminescent. The method was tested using perylene diimide (PDI) molecules functionalized with p-phenylene phosphonic acid (PA) moieties that bind strongly to indium-tin oxide (ITO). Conditions to prepare PDI-phenyl-PA films that exhibit absorbance and fluorescence spectra characteristic of monomeric (i.e., nonaggregated) molecules were identified; the electrochemical surface coverage was approximately 0.03 monolayer. The tilt angle of the long axis of the PDI molecular plane is 58° relative to the ITO surface normal, 25° greater than the tilt angle of aggregated PDI-phenyl-PA films, which have a surface coverage of approximately one monolayer. The more in-plane orientation of monomeric films is likely due to the absence of cofacial π-π interactions present in aggregated films and possibly a difference in PA-ITO binding modes. The electron transfer rate constant (ks,opt) of monomeric PDI-phenyl-PA films was determined using PM-TIRF and compared with PM-ATR results obtained for aggregated films. For PDI monomers, ks,opt = 3.8 × 103 s-1, which is about 3.7-fold less than ks,opt for aggregated films. The slower kinetics are attributed to the absence of electron self-exchange between monomeric PDI molecules. Differences in the electroactivity of the binding sites on the ITO electrode surface also may play a role. This is the first demonstration of PM-TIRF for determining electron transfer rate constants at an electrode/organic film interface.

10.
Animals (Basel) ; 10(1)2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-31947586

RESUMEN

Camera trapping has become an increasingly reliable and mainstream tool for surveying a diversity of wildlife species. Concurrent with this has been an increasing effort to involve the wider public in the research process, in an approach known as 'citizen science'. To date, millions of people have contributed to research across a wide variety of disciplines as a result. Although their value for public engagement was recognised early on, camera traps were initially ill-suited for citizen science. As camera trap technology has evolved, cameras have become more user-friendly and the enormous quantities of data they now collect has led researchers to seek assistance in classifying footage. This has now made camera trap research a prime candidate for citizen science, as reflected by the large number of camera trap projects now integrating public participation. Researchers are also turning to Artificial Intelligence (AI) to assist with classification of footage. Although this rapidly-advancing field is already proving a useful tool, accuracy is variable and AI does not provide the social and engagement benefits associated with citizen science approaches. We propose, as a solution, more efforts to combine citizen science with AI to improve classification accuracy and efficiency while maintaining public involvement.

11.
Am J Otolaryngol ; 40(6): 102185, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31376924

RESUMEN

BACKGROUND: Transoral treatment of benign and malignant lesions of laryngopharynx has limitations in exposure and access, partially due to the endotracheal tube (ETT). With a proper airway control to tailor ventilation and maximize exposure, transoral Flex robotic surgery (FLEX), using its 3D camera and instruments, can expand its ability. Choosing the right ETT, including a novel concept of using jet ventilation (JV) in FLEX, and placement technique can allow augmentation of the advantages that robotic surgery offers. METHODS: Chart review of FLEX assisted procedures was performed. Attention was given to demographics, all events of airway manipulation and ventilation type, procedures performed and outcomes including adverse effects. RESULTS: Fifty-two patients underwent eighty procedures. The airway was manipulated sixty-four times to include 8 JV. All possible FLEX instruments including CO2 laser were used. Three novel possible indications for trans-oral robotic surgery including the feasibility of JV in FLEX procedures were shown. CONCLUSIONS: Lesions of the tongue base, hypopharynx, larynx and trachea have the possibility to be managed with adequate exposure with minimal obstruction from ETT. Robotic HD camera permits both the surgeon and anesthesiologist to observe surgery and safely monitor the airway. An algorithm was developed for selecting ideal ventilation method for different procedures. The FLEX and the utilization of JV allows flexibility of two instruments without obstruction.


Asunto(s)
Anestesia , Hipofaringe/cirugía , Procedimientos Quirúrgicos Otorrinolaringológicos , Respiración Artificial , Procedimientos Quirúrgicos Robotizados , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
13.
Pain Physician ; 21(2): 179-190, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29565948

RESUMEN

BACKGROUND: Sodium nitrite has been reported to be effective in reducing chronic peripheral pain. OBJECTIVES: To evaluate the safety and efficacy of 40 and 80 mg, BID, of an oral sustained release formulation of sodium nitrite (SR-nitrite) in patients suffering from diabetic neuropathy, and to determine whether SR-nitrite would reduce the frequency of headaches reported previously by subjects receiving the same doses of an immediate release formulation. STUDY DESIGN: Phase II, single-center, randomized, double-blind, placebo controlled clinical trial. SETTING: The Ohio Pain Clinic and Kettering Medical Center. METHODS: Twenty-four patients were randomized to 40 mg or 80 mg SR-nitrite or placebo twice daily for 12 weeks. The primary objective was to determine whether headaches would be reduced using SR-nitrite. The primary efficacy endpoint was the mean difference in the change of the Neuropathic Pain Symptom Inventory (NPSI) pain score from baseline to that reported after 12 weeks of treatment. Secondary endpoints included changes from baseline for the Brief Pain Inventory (BPI) Scale, the RAND 36 questionnaire, Short Form McGill Questionnaire, daily patient reported score for neuropathic pain, changes in HbA1c, PulseOx and quantitative sensory testing. RESULTS: The number of subjects reporting adverse events and the number of adverse events did not change with dose. There were no reports of treatment-related headaches. Although no significant differences were identified in patient responses to the questionnaires, a trend was observed. In the NPSI assessment, patients in the 40 mg and 80 mg dose group reported a 12.7% and 22.0% reduction in pain, respectively, compared to an 8.4% reduction by patients in the placebo group. A trend was also observed with the BPI total severity score. However, the 40 mg dosing group reported the greatest reduction in pain using the McGill Pain index and via patient logs of daily pain scores, where the mean of pain scores reported by subjects in the 40 mg group dropped by day 41 and generally stayed lower than the mean of scores reported by subjects in either of the other two groups. Patients in the 80 mg SR-nitrite group had an improvement in both Nerve Sensory Conductance and Nerve Sensory Velocity. No changes were observed in HbA1c levels or PulseOx. LIMITATIONS: Small sample size. CONCLUSION: Sustained release sodium nitrite prevents the prevalent reports of headaches by patients treated with an immediate release formulation of sodium nitrite. In a previous study of patients with peripheral arterial disease (PAD), 40 mg BID treatment led to a statistically significant reduction in reported pain, similar trends were observed at the end of the trial period for most of the pain questionnaires used in the study. The 80 mg BID treatment had the more pronounced affect on bioactivity (quantitative sensory testing), which was similar to the PAD study, where this dose group had the greatest improvement in FMD {AU: spell out FMD}. The ability to alleviate pain with BID treatment of SR-nitrite offers promise for a new non-addictive, non-sedating treatment of chronic pain and warrants further study. KEY WORDS: Diabetes, diabetic neuropathy, neuropathic pain, peripheral neuropathy, sodium nitrite.


Asunto(s)
Neuropatías Diabéticas/tratamiento farmacológico , Neuralgia/tratamiento farmacológico , Nitrito de Sodio/uso terapéutico , Adulto , Anciano , Dolor Crónico/tratamiento farmacológico , Preparaciones de Acción Retardada/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Resultado del Tratamiento
14.
CMAJ ; 190(11): E337, 2018 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-29555866
16.
Proc Biol Sci ; 284(1847)2017 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-28100818

RESUMEN

The responses of lowland tropical communities to climate change will critically influence global biodiversity but remain poorly understood. If species in these systems are unable to tolerate warming, the communities-currently the most diverse on Earth-may become depauperate ('biotic attrition'). In response to temperature changes, animals can adjust their distribution in space or their activity in time, but these two components of the niche are seldom considered together. We assessed the spatio-temporal niches of rainforest mammal species in Borneo across gradients in elevation and temperature. Most species are not predicted to experience changes in spatio-temporal niche availability, even under pessimistic warming scenarios. Responses to temperature are not predictable by phylogeny but do appear to be trait-based, being much more variable in smaller-bodied taxa. General circulation models and weather station data suggest unprecedentedly high midday temperatures later in the century; predicted responses to this warming among small-bodied species range from 9% losses to 6% gains in spatio-temporal niche availability, while larger species have close to 0% predicted change. Body mass may therefore be a key ecological trait influencing the identity of climate change winners and losers. Mammal species composition will probably change in some areas as temperatures rise, but full-scale biotic attrition this century appears unlikely.


Asunto(s)
Tamaño Corporal , Cambio Climático , Mamíferos , Animales , Biodiversidad , Borneo , Bosque Lluvioso , Temperatura
17.
Chem Rev ; 116(12): 7117-58, 2016 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-27227316

RESUMEN

Transparent conducting oxides (TCOs), such as indium tin oxide and zinc oxide, play an important role as electrode materials in organic-semiconductor devices. The properties of the inorganic-organic interface-the offset between the TCO Fermi level and the relevant transport level, the extent to which the organic semiconductor can wet the oxide surface, and the influence of the surface on semiconductor morphology-significantly affect device performance. This review surveys the literature on TCO modification with phosphonic acids (PAs), which has increasingly been used to engineer these interfacial properties. The first part outlines the relevance of TCO surface modification to organic electronics, surveys methods for the synthesis of PAs, discusses the modes by which they can bind to TCO surfaces, and compares PAs to alternative organic surface modifiers. The next section discusses methods of PA monolayer deposition, the kinetics of monolayer formation, and structural evidence regarding molecular orientation on TCOs. The next sections discuss TCO work-function modification using PAs, tuning of TCO surface energy using PAs, and initiation of polymerizations from TCO-tethered PAs. Finally, studies that examine the use of PA-modified TCOs in organic light-emitting diodes and organic photovoltaics are compared.

18.
Parasit Vectors ; 9: 242, 2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-27125995

RESUMEN

BACKGROUND: Plasmodium knowlesi is a zoonotic pathogen, transmitted among macaques and to humans by anopheline mosquitoes. Information on P. knowlesi malaria is lacking in most regions so the first step to understand the geographical distribution of disease risk is to define the distributions of the reservoir and vector species. METHODS: We used macaque and mosquito species presence data, background data that captured sampling bias in the presence data, a boosted regression tree model and environmental datasets, including annual data for land classes, to predict the distributions of each vector and host species. We then compared the predicted distribution of each species with cover of each land class. RESULTS: Fine-scale distribution maps were generated for three macaque host species (Macaca fascicularis, M. nemestrina and M. leonina) and two mosquito vector complexes (the Dirus Complex and the Leucosphyrus Complex). The Leucosphyrus Complex was predicted to occur in areas with disturbed, but not intact, forest cover (> 60% tree cover) whereas the Dirus Complex was predicted to occur in areas with 10-100% tree cover as well as vegetation mosaics and cropland. Of the macaque species, M. nemestrina was mainly predicted to occur in forested areas whereas M. fascicularis was predicted to occur in vegetation mosaics, cropland, wetland and urban areas in addition to forested areas. CONCLUSIONS: The predicted M. fascicularis distribution encompassed a wide range of habitats where humans are found. This is of most significance in the northern part of its range where members of the Dirus Complex are the main P. knowlesi vectors because these mosquitoes were also predicted to occur in a wider range of habitats. Our results support the hypothesis that conversion of intact forest into disturbed forest (for example plantations or timber concessions), or the creation of vegetation mosaics, will increase the probability that members of the Leucosphyrus Complex occur at these locations, as well as bringing humans into these areas. An explicit analysis of disease risk itself using infection data is required to explore this further. The species distributions generated here can now be included in future analyses of P. knowlesi infection risk.


Asunto(s)
Culicidae/fisiología , Macaca , Malaria/parasitología , Enfermedades de los Monos/parasitología , Plasmodium knowlesi/aislamiento & purificación , Animales , Asia Sudoriental/epidemiología , Culicidae/parasitología , Bosques , Malaria/epidemiología , Enfermedades de los Monos/epidemiología
19.
J Foot Ankle Surg ; 55(5): 1038-42, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26232885

RESUMEN

An intermetatarsal coalition is an uncommon pathologic entity, previously reported in published studies as being primarily unilateral, most commonly between the first and second metatarsals and less so between the third and fourth metatarsals. We report an unusual case of a bilateral coalition of the third and fourth metatarsals in a 43-year-old male who presented with nonspecific dorsolateral foot pain. Conservative therapy initially failed, and resolution of pain was noted bilaterally after coalition resection.


Asunto(s)
Imagenología Tridimensional , Huesos Metatarsianos/anomalías , Huesos Metatarsianos/cirugía , Osteotomía/métodos , Sinostosis/cirugía , Adulto , Estudios de Seguimiento , Deformidades Congénitas del Pie/diagnóstico por imagen , Deformidades Congénitas del Pie/cirugía , Humanos , Masculino , Huesos Metatarsianos/diagnóstico por imagen , Osteotomía/rehabilitación , Dimensión del Dolor , Cuidados Posoperatorios/métodos , Medición de Riesgo , Sinostosis/diagnóstico por imagen , Factores de Tiempo , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
20.
Langmuir ; 31(20): 5603-13, 2015 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-25924006

RESUMEN

Self-assembled monolayers (SAMs) of phosphonic acids (PAs) on transparent conductive oxide (TCO) surfaces can facilitate improvement in TCO/organic semiconductor interface properties. When ordered PA SAMs are formed on oxide substrates, interface dipole and electronic structure are affected by the functional group properties, orientation, and binding modes of the modifiers. Choosing octylphosphonic acid (OPA), F13-octylphosphonic acid (F13OPA), pentafluorophenyl phosphonic acid (F5PPA), benzyl phosphonic acid (BnPA), and pentafluorobenzyl phosphonic acid (F5BnPA) as a representative group of modifiers, we report polarization modulation-infrared reflection-absorption spectroscopy (PM-IRRAS) of binding and molecular orientation on indium-doped zinc oxide (IZO) substrates. Considerable variability in molecular orientation and binding type is observed with changes in PA functional group. OPA exhibits partially disordered alkyl chains but on average the chain axis is tilted ∼57° from the surface normal. F13OPA tilts 26° with mostly tridentate binding. The F5PPA ring is tilted 23° from the surface normal with a mixture of bidentate and tridentate binding; the BnPA ring tilts 31° from normal with a mixture of bidentate and tridentate binding, and the F5BnPA ring tilts 58° from normal with a majority of bidentate with some tridenate binding. These trends are consistent with what has been observed previously for the effects of fluorination on orientation of phosphonic acid modifiers. These results from PM-IRRAS are correlated with recent results on similar systems from near-edge X-ray absorption fine structure (NEXAFS) and density functional theory (DFT) calculations. Overall, these results indicate that both surface binding geometry and intermolecular interactions play important roles in dictating the orientation of PA modifiers on TCO surfaces. This work also establishes PM-IRRAS as a routine method for SAM orientation determination on complex oxide substrates.

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