934 research outputs found

    Increasing High School STEM Participation Through Robotics Training and Tournaments (FINAL REPORT)

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    The overall goal of this project was to engage high school students in an exciting way to increase their interest in science and technology. We planned to accomplish this by making Pace University an official Affiliate Partner of the FIRST Tech Challenge (FTC) robotics competition, a fast-growing program with more than 1,100 participating teams in 2009-2010. In FTC, high-school age participants design, build, and program their own robots to enter into regional and national competitions. Building on the Seidenberg School’s past success as a partner to FIRST with its FIRST LEGO League program, we intended to organize, host, and run several top-notch FTC events, bringing smart and enthusiastic high school students to our campuses to interact with Pace students and faculty

    Increasing High School STEM Participation Through Robotics Training and Tournaments (INTERIM REPORT)

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    The overall goal was to excite area high school students in science and technology through the design, building, and programming of robots which they use in international competitions, and to bring them to several such events held at and run by Pace University

    Nothing but the Law of the Land Robert C. Grier: jacksonian unionist

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    From 1846 to 1870 Robert Cooper Grier, a Pennsylvania Jacksonian Democrat, served as an Associate Justice of the United States Supreme Court and Third Circuit Court Justice. In judicial opinions and decisions and in personal and polictical correspondence, he expressed an unyielding commitment to the preservation of the Union

    Roots of the Lemon Tree

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    The role of intermolecular coupling in the photophysics of disordered organic semiconductors: Aggregate emission in regioregular polythiophene

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    We address the role of excitonic coulping on the nature of photoexcitations in the conjugated polymer regioregular poly(3-hexylthiophene). By means of temperature-dependent absorption and photoluminescence spectroscopy, we show that optical emission is overwhelmingly dominated by weakly coupled H-aggregates. The relative absorbance of the 0-0 and 0-1 vibronic peaks provides a powerfully simple means to extract the magnitude of the intermolecular coupling energy, approximately 5 and 30 meV for films spun from isodurene and chloroform solutions respectively.Comment: 10 pages, 4 figures, published in Phys. Rev. Let

    Evidence of an established population of Cherax quadricarinatus (von Martens, 1868) in south Texas, USA

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    Cherax quadricarinatus (von Martens, 1868) is a large parastacid crayfish (Decapoda: Parastacidae) native to Australia and Papua New Guinea. Due to various factors, C. quadricarinatus is an emerging invasive species in an increasing number of regions across the world. Deleterious ecological effects of C. quadricarinatus introduction have been documented in many of these regions, and its spread has been monitored and restricted where possible. Previously, only a small, isolated population of C. quadricarinatus in southern California had been reported within the continental United States. Here, we report the collection of three adult C. quadricarinatus from Brownsville, Cameron County, Texas, the first record of this species in the state and only the second record for the continental United States. Given the connectivity of aquatic habitats in the area and the duration for which the population has likely been present, there is evidence that C. quadricarinatus is poised to invade subtropical watersheds of the southern United States. The ecological effects of C. quadricarinatus on aquatic ecosystems in the region are not yet fully understood, but further research is warranted to effectively mitigate negative impacts that may occur and to guide efforts to manage or eradicate these population

    Applications of environmental DNA (eDNA) to detect subterranean and aquatic invasive species: A critical review on the challenges and limitations of eDNA metabarcoding

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    The world is struggling to solve a devastating biodiversity loss that not only affects the extinction of treasured species and irreplaceable genetic variation, but also jeopardizes the food production, health, and safety of people. All initiatives aimed to conserve biodiversity rely heavily on the monitoring of both species and populations to get accurate spatial patterns and overall population assessments. Conventional monitoring techniques, such as visual surveys and counting individuals, are problematic due to challenges in identifying cryptic species or immature life stages. Environmental DNA (eDNA) is a relatively new technology that has the potential to be a faster, non-invasive, and cost-effective tool for monitoring biodiversity, conservation, and management practices. eDNA has been extracted from materials that are both ancient and present, and its applications range from the identification of individual species to the study of entire ecosystems. In the past few years, there has been a substantial increase in the usage of eDNA in research pertaining to ecological preservation and conservation. However, several technological problems still need to be solved. To reduce the number of false positives and/or false negatives produced by current eDNA technologies, it is necessary to improve and optimize calibration and validation at every stage of the procedure. There is a significant need for greater information about the physical and ecological constraints on eDNA use, as well as its synthesis, current state, expected lifespan, and potential modes of movement. Due to the widespread use of eDNA research, it is also essential to assess the extent and breadth of these studies. In this article, we critically reviewed the primary applications of eDNA in subterranean and aquatic invasive species. Through this review, readers can better understand the challenges and limitations of eDNA metabarcoding

    Behavior, Color Change and Time for Sexual Inversion in the Protogynous Grouper (Epinephelus adscensionis)

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    Hermaphroditism, associated with territoriality and dominance behavior, is common in the marine environment. While male sex-specific coloration patterns have been documented in groupers, particularly during the spawning season, few data regarding social structure and the context for these color displays are available. In the present study, we define the social structure and male typical behavior of rock hind (Epinephelus adscensionis) in the wild. In addition, we detail the captive conditions and time period necessary to induce the onset of the sex-specific coloration and sexual change. At six oil production platform locations in the Gulf of Mexico, rock hind social group size and typical male rock hind social behavior were documented. We observed a rapid temporary color display in rock hind that could be turned on and off within three seconds and was used for confronting territory intruders and displays of aggression towards females. The male-specific β€œtuxedo” pattern consists of a bright yellow tail, a body with alternating dark brown and white patches and a dark bar extending from the upper mandible to the operculum. Identification and size ranges of male, female and intersex fish collected from oil platforms were determined in conjunction with gonadal histology. Rock hind social order is haremic with one dominant male defending a territory and a linear dominance hierarchy among individuals. In five captive experiments, the largest remaining female rock hind displayed the male specific color pattern within 32d after dominant male removal from the social group. To our knowledge, this is the first evidence in a grouper species of color patterning used to display territoriality and dominance outside of spawning aggregations. The behavioral paradigm described here is a key advance that will enable mechanistic studies of this complex sex change process

    Recruitment Patterns of Juvenile Fish at an Artificial Reef Area in the Gulf of Mexico

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    In 2011 the Texas Parks and Wildlife Department and the Coastal Conservation Association of Texas deployed over 4,000 concrete culverts in a designated artificial reef area off Port Mansfield, Texas, to enhance habitat for sport fish species in the Gulf of Mexico. A study was conducted to assess juvenile fish recruitment at varying culvert densities within the artificial reef area. Standard monitoring units for the recruitment of reef fish (SMURFs) were used to sample juvenile fish, and these collections were compared with visual scuba surveys. The 0.027-m3 SMURFs were placed at four different culvert densities (0, 1–50, 51–100, and 101+ culverts in a 30-m radius) and sampled during 2013 to 2014. Measurements of rugosity, vertical relief, and percent cover were collected to elucidate factors that drive juvenile recruitment. Average species richness was highest at sites with no culverts and lowest at dense culvert sites. Species compositions were significantly different between sampling locations with no culverts and all locations with culverts; average similarity was 33.8%. Belted Sandfish Serranus subligarius was the most ubiquitous species among all sampling locations. Visual scuba surveys at the same locations showed lower diversity indices of the juvenile fish community than observed by SMURFs and were only 14% similar to the community sampled by the SMURFs. These findings suggest SMURFs are a more effective tool for examining juvenile fish at an artificial reef due to the cryptic nature of juveniles and the low visibility around shallow reefs. Additionally, commercially important Yellowedge Grouper Hyporthodus flavolimbatus, Warsaw Grouper H. nigritus, and Red Snapper Lutjanus campechanus juveniles were only found at SMURFs at sampling locations with no culverts. The presence of juveniles of these key species suggest that fisheries management may benefit from creating low-relief reef patches away from the main reef where juvenile fish can recruit and grow
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