50 research outputs found

    Iran and Iraq: An Overview

    Get PDF
    Iran and Iraq, two of the major producers of crude and refined oil in the Persian Gulf have been at war for over three years now. Why, with oil so important to the industrial nations, has there not been a greater effort made to end this seemingly unnecessary drain on the area\u27s economy

    Habitat Selection Among Fishes and Shrimp in the Pelagic Sargassum Community: The Role of Habitat Architecture

    Get PDF
    The pelagic Sargassum community represents an excellent model system to advance our understanding of how a complex habitat can influence biotic interactions. This study examined the habitat architecture of pelagic Sargassum fluitans to determine its effects on habitat selection for one shrimp species (Leander tenuicornis) and two fish species (Stephanolepis hispidus and Histrio histrio). Specifically, we manipulated interthallus spacing and depth of Sargassum habitats independently (i.e., in separate experimental trials) to test whether spatial components of habitat architecture influence habitat selection by these animal inhabitants. Additionally, two differing habitats (Sargassum vs intermingled seagrass species, Thalassia testudinum and Syringodium filiforme) were tested to determine whether structural components of habitat architecture influenced habitat selection. Results showed no significant effect of habitat selections for interthallus spacing experiments for L. tenuicornis and S. hispidus. However, H. histrio selected habitats with medium interthallus spacing characteristics in two experiments. All three animals selected habitats with a greater depth aspect. Finally, L. tenuicornis and H. histrio selected habitats with greater structural complexity (i.e., Sargassum habitat). These results demonstrate that habitat architecture (i.e., spatial and structural components) of Sargassum influences habitat selection by the aforementioned fauna and further illustrate that this pelagic macroalga is an essential habitat for multiple species

    Interactive, Mobile Internet of Things Device with Image Capture Capability

    Get PDF
    Aspects of the present disclosure are directed to an interactive, mobile Internet of Things (IoT) device with image capture capability. In particular, one example embodiment of the present disclosure is a “life-size” (e.g., around 4-6 feet in height) anthropomorphic device that can move around an environment and interact with humans and/or other devices in the area. For example, the device can respond to commands and/or capture images of and/or with humans in the area. As one example, the captured images can be in the style of a self-portrait photograph (also known as a “selfie”) and can depict the device positioned alongside one or more humans

    Interactive Surface-Mounted Internet of Things Device

    Get PDF
    Aspects of the present disclosure are directed to an interactive lighting device that includes sensor-equipped lighting elements that respond to users. In one particular example, the interactive lighting device of the present disclosure can include a structure (e.g., a custom designed structure) fashioned in the shape of a planter (e.g., a container for live plants) that can be mounted on a surface (e.g., a wall) and which can provide various lighting effects based on events (e.g., the presence or movement of users) detected by sensors of the interactive lighting device. For example, the interactive lighting device can control lighting elements such as light emitting diodes (LEDs) based on outputs from various types of sensors (e.g., step sensor, gesture sensor, proximity sensor, or an image sensor). In some embodiments, sensor data can be aggregated to produce different results as shown in camera and proximity sensors

    Jump-Start Reinforcement Learning

    Full text link
    Reinforcement learning (RL) provides a theoretical framework for continuously improving an agent's behavior via trial and error. However, efficiently learning policies from scratch can be very difficult, particularly for tasks with exploration challenges. In such settings, it might be desirable to initialize RL with an existing policy, offline data, or demonstrations. However, naively performing such initialization in RL often works poorly, especially for value-based methods. In this paper, we present a meta algorithm that can use offline data, demonstrations, or a pre-existing policy to initialize an RL policy, and is compatible with any RL approach. In particular, we propose Jump-Start Reinforcement Learning (JSRL), an algorithm that employs two policies to solve tasks: a guide-policy, and an exploration-policy. By using the guide-policy to form a curriculum of starting states for the exploration-policy, we are able to efficiently improve performance on a set of simulated robotic tasks. We show via experiments that JSRL is able to significantly outperform existing imitation and reinforcement learning algorithms, particularly in the small-data regime. In addition, we provide an upper bound on the sample complexity of JSRL and show that with the help of a guide-policy, one can improve the sample complexity for non-optimism exploration methods from exponential in horizon to polynomial.Comment: 20 pages, 10 figure

    Genetic confirmation of Octopus insularis (Leite and Haimovici, 2008) in South Florida, United States using physical features and de novo genome assembly

    Get PDF
    The distribution of octopuses within the Octopus vulgaris species complex remains inadequately understood. Species determination can be complex and involves characterizing a specimen’s physical features and comparing its genetic makeup to other populations. In this study, we present the first genetic confirmation of Octopus insularis (Leite and Haimovici, 2008) inhabiting the coastal waters of the Florida Keys, United States. We employed visual observations to identify species-specific body patterns of three wild-caught octopuses and used de novo genome assembly to confirm their species. All three specimens exhibited a red/white reticulated pattern on their ventral arm surface. Two specimens displayed body pattern components of deimatic display (white eye encircled by a light ring, with darkening around the eye). All visual observations were consistent with distinguishing features of O. insularis. We then compared mitochondrial subunits COI, COIII, and 16S in these specimens across all available annotated octopod sequences, including Sepia apama (Hotaling et al., 2021) as a control outgroup taxon. For species exhibiting intraspecific genomic variation, we included multiple sequences from geographically distinct populations. Laboratory specimens consistently clustered into a single taxonomic node with O. insularis. These findings confirm O. insularis presence in South Florida and suggest a more extensive northern distribution than previously assumed. Whole genome Illumina sequencing of multiple specimens enabled taxonomic identification with well-established DNA barcodes while also generating the first de novo full assembly of O. insularis. Furthermore, constructing and comparing phylogenetic trees for multiple conserved genes is essential for confirming the presence and delineation of cryptic species in the Caribbean

    Estudio comparativo entre banda de tensión y tornillo compresivo para la artrodesis interfalángica proximal y metacarpofalángica

    Get PDF
    Resumen Introducción: Los métodos más utilizados para la artrodesis de la articulación interfalángica proximal y metacarpofalángica son la banda de tensión y el tornillo compresivo. El objetivo de este estudio fue comparar los resultados entre pacientes tratados con estas técnicas. Materiales y Métodos: Estudio comparativo retrospectivo de 10 años. Se incluyeron pacientes esqueléticamente maduros tratados por artrosis y artritis. Se analizaron la tasa de consolidación ósea, el tiempo hasta la consolidación, la incidencia de complicaciones y la tasa de reoperaciones. En un análisis secundario, se compararon los pacientes reumáticos y no reumáticos. Resultados: Se evaluaron 56 casos en 44 pacientes (edad promedio 53 años). Grupo 1: 35 casos tratados con banda de tensión y grupo 2: 21 tratados con tornillo compresivo. Había 32 casos reumáticos y 24 no reumáticos. El seguimiento promedio fue de 24 meses. La tasa promedio de consolidación fue del 94,2% en el grupo 1 y del 85,7% en el grupo 2. La incidencia de complicaciones fue del 11,4% en el primer grupo y 23,8% en el segundo, y la tasa de reoperaciones, del 17,1% y del 0%, respectivamente. Conclusiones: Ambos métodos permiten lograr tasas altas de consolidación, pero la incidencia de seudoartrosis fue casi tres veces superior con el tornillo compresivo que con la banda de tensión. La tasa más alta de reoperaciones en el grupo con banda de tensión fue por extracción del material. El tiempo de consolidación fue más corto en los pacientes no reumáticos, independientemente de la técnica. Palabras clave: Artrodesis; fusión interfalángica proximal y metacarpofalángica; banda de tensión; tornillo compresivo. Nivel de Evidencia: II

    Show your beaks and we tell you what you eat: Different ecology in sympatric Antarctic benthic octopods under a climate change context

    Get PDF
    Sympatry can lead to higher competition under climate change and other environmental pressures, including in South Georgia, Antarctica, where the two most common octopod species, Adelieledone polymorpha and Pareledone turqueti, occur side by side. Since cephalopods are typically elusive animals, the ecology of both species is poorly known. As beaks of cephalopods are recurrently found in top predator's stomachs, we studied the feeding ecology of both octopods through the evaluation of niche overlapping and specific beak adaptations that both species present. A multidisciplinary approach combining carbon (δ13C) and nitrogen (δ15N) stable isotope signatures, mercury (Hg) analysis and biomaterials' engineering techniques was applied to investigate the beaks. An isotopic niche overlap of 95.6% was recorded for the juvenile stages of both octopod species, dropping to 19.2% for the adult stages. Both A. polymorpha and P. turqueti inhabit benthic ecosystems around South Georgia throughout their lifecycles (δ13C: −19.21 ± 1.87‰, mean ± SD for both species) but explore trophic niches partially different during adult life stages (δ15N: 7.01 ± 0.40‰, in A. polymorpha, and 7.84 ± 0.65‰, in P. turqueti). The beaks of A. polymorpha are less dense and significantly less stiff than in P. turqueti. Beaks showed lower mercury concentration relative to muscle (A. polymorpha - beaks: 0.052 ± 0.009  μg g−1, muscle: 0.322 ± 0.088  μg g−1; P. turqueti - beaks: 0.038 ± 0.009  μg g−1; muscle: 0.434 ± 0.128  μg g−1). Overall, both octopods exhibit similar habitats but different trophic niches, related to morphology/function of beaks. The high Hg concentrations in both octopods can have negative consequences on their top predators and may increase under the present climate change context.British Antarctic Survey for assisting in the collection of the specimens for this work. Many thanks to 3B's Research Group (University of Minho) and MAREFOZ who were responsible for analysing the physical properties of beaks and stable isotope signatures. A special thank you to our colleague José Queirós from MARE-UC (Coimbra, Portugal) for his suggestions and guidance. A debt of gratitude is also owed to Dr. A. Louise Allcock (NUI Galway) for her useful guidelines. This work is an international effort under the Scientific Committee on Antarctic Research (SCAR) associated programs, expert and action groups, namely SCAR AnT-ERA, SCAR EGBAMM and ICED. J.C. Xavier was supported by the Investigator Programme (IF/00616/2013) of the Foundation for Science and Technology (FCT-Portugal) and PROPOLAR, and F.R. Ceia was supported by a postdoctoral fellowship (SFRH/BPD/95372/2013) attributed by FCT-Portugal and the European Social Fund (POPH, EU). This study benefited from the strategic program of MARE, financed by FCT-Portugal (MARE- UID/MAR/04292/2019). We also acknowledge FCT-Portugal through a PhD grant to J. Seco (SRFH/PD/BD/113487

    Recovery from depressive symptoms, state anxiety and post-traumatic stress disorder in women exposed to physical and psychological, but not to psychological intimate partner violence alone: A longitudinal study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>It is well established that intimate male partner violence (IPV) has a high impact on women's mental health. It is necessary to further investigate this impact longitudinally to assess the factors that contribute to its recovery or deterioration. The objective of this study was to assess the course of depressive, anxiety and post-traumatic stress disorder (PTSD) symptoms and suicidal behavior over a three-year follow-up in female victims of IPV.</p> <p>Methods</p> <p>Women (n = 91) who participated in our previous cross-sectional study, and who had been either physically/psychologically (n = 33) or psychologically abused (n = 23) by their male partners, were evaluated three years later. A nonabused control group of women (n = 35) was included for comparison. Information about mental health status and lifestyle variables was obtained through face-to-face structured interviews.</p> <p>Results</p> <p>Results of the follow-up study indicated that while women exposed to physical/psychological IPV recovered their mental health status with a significant decrease in depressive, anxiety and PTSD symptoms, no recovery occurred in women exposed to psychological IPV alone. The evolution of IPV was also different: while it continued across both time points in 65.21% of psychologically abused women, it continued in only 12.12% of physically/psychologically abused women while it was reduced to psychological IPV in 51.5%. Hierarchical multiple regression analyses indicated that cessation of physical IPV and perceived social support contributed to mental health recovery, while a high perception of lifetime events predicted the continuation of PTSD symptoms.</p> <p>Conclusion</p> <p>This study shows that the pattern of mental health recovery depends on the type of IPV that the women had been exposed to. While those experiencing physical/psychological IPV have a higher likelihood of undergoing a cessation or reduction of IPV over time and, therefore, could recover, women exposed to psychological IPV alone have a high probability of continued exposure to the same type of IPV with a low possibility of recovery. Thus, women exposed to psychological IPV alone need more help to escape from IPV and to recuperate their mental health. Longitudinal studies are needed to improve knowledge of factors promoting or impeding health recovery to guide the formulation of policy at individual, social and criminal justice levels.</p
    corecore