799 research outputs found

    IR Motion Tracking Robotic Arm

    Get PDF
    The Motion Tracking Robot Arm is a senior Electrical Engineering Capstone project designed by Andrew Doan, Avery Guillermo, Gavin Low, and Dayna Yoshimura. The project serves as an exploration of alternative control methods for robotic arms. While standard robotic arms are often controlled with physical controllers or computer programs, this robotic arm will be controlled with a LEAP motion controller. The user will be able to control the robotic arm using his or her own arm; no extra control inputs will be necessary.https://pilotscholars.up.edu/egr_project/1005/thumbnail.jp

    Encapsulation of flutriafol fungicide into electrospun biodegredable poly (L-lactide) nanofibers

    Get PDF
    The application of biodegradable, electrospun nanofibers in agriculture has attracted a lot of interest as they are cost-effective and offer a versatile technique to fabricate eco-friendly, high surface-to-volume ratio and porous nanofibrous structures from polymeric solutions. Flutriafol is a commonly used fungicide in plant protection in Australia. This study aimed to encapsulate flutriafol into poly(L-lactide) (PLLA) nanofibers matrix by optimizing electrospinnig conditions. The PLLA solution was prepared at concentration of PLLA (5% w/w) in chloroform-Aceton (75–25 v/v) containing 10% (w/w) flutriafol relative to the PLLA. The PLLA/flutriafol mixture was fed with a syringe to a basic electrospinning setup. Optimum electrospinning conditions were observed at 32 °C with a flow rate speed of 1mL/ h, and 12kV high voltage. SEM images were used to characterize the morphology of electrospun nanofibers. Energy-dispersive detector (EDS) was employed to identify successful encapsultion of flutrifol into PLLA nanofibers

    Kinetics of slow release of nitrogen fertiliser from multi-layered nanofibrous structures

    Get PDF
    Fertilisers are essential in modern agriculture to enhance plant growth, crop production and product quality. Recent research has focused on the development of delivery systems designed to prolong fertiliser release. This study introduces a new technology to encapsulate and release molecules of fertilisers by using multi-layered electrospun nanofibre as a carrier. Single-layer poly L-lactic acid (PLLA) nanofibres loaded with urea were fabricated using electrospinning. Triple-layer nanofibrous structures were produced by electrospinning polyhydroxybutyrate (PHB) nanofibres as external layers with PLLA nanofibres impregnated with urea fertiliser as the middle layer. Scanning electron microscopy (SEM) and Fourier transform infrared spectrophotometry (FTIR) were employed to characterize the morphology of electrospun nanofibres. Urea release dynamic was analysed using a total nitrogen instrument (TNM-1). The results indicated that triple-layered urea-impregnated nanofibrous structures led to lower initial rate of nitrogen release and slower release rate of cumulative nitrogen which extended for more than three months. It is concluded that triple-layer nanofibrous structures have the potential for slow release delivery of fertilisers

    Abdominal and pelvic radiographs of medical devices and materials- part 2: neurologic and genitourinary devices and materials

    Get PDF
    Radiographs of the abdomen and pelvis are routinely obtained as a standard part of clinical care for the abdomen and pelvis. Brisk advances in technology over the last few decades have resulted in a multitude of medical devices and materials. Recognizing and evaluating these devices on abdominal and pelvic radiographs are critical, yet increasingly a difficult endeavor. In addition, multiple devices serving different purposes may have a similar radiographic appearance and position causing confusion for the interpreting radiologist. The role of the radiologist is to not only identify accurately these medical objects, but also to confirm for their accurate placement and to recognize any complications that could affect patient care, management or even be potentially life threatening. An extensive online search of literature showed our review article to be the most comprehensive work on medical devices and materials of the abdomen and pelvis, and in this second part of our two-part series, we discuss in depth about the neurologic and genitourinary devices seen on abdominal and pelvic radiographs

    Abdominal and pelvic radiographs of medical devices and materials—Part 1: gastrointestinal and vascular devices and materials

    Get PDF
    When compared with chest radiographs, medical devices of the abdomen and pelvis are less frequently seen. However, with recent advances in technology the interpreting radiologists are seeing more medical objects on these radiographs. The identification of these devices and materials are crucial for not only enabling the radiologist to understand the underlying background pathology but also for evaluating any related complications. An online survey of literature showed our review article to be the most detailed. In this first part of our two-part series, we discuss about the various gastrointestinal and vascular devices and materials seen on abdominal and pelvic radiographs

    The evolution and ecology of land ownership

    Get PDF
    Land ownership norms play a central role in social-ecological systems, and have been studied extensively as a component of ethnographies. Yet only recently has the distribution of land ownership norms across cultures been examined from evolutionary and ecological perspectives. Here we incorporate evolutionary and macroecological modelling to test associations between land ownership norms and environmental, subsistence, and cultural contact predictors for societies in the Bantu language family. We find that Bantu land ownership norms likely evolved on a unilinear trajectory, but not necessarily one requiring consistent increase in exclusivity as suggested by prior theory. Our macroecological analyses suggest that Bantu societies are more likely to have some form of ownership when their neighbors also do. We also find an effect of environmental productivity, supporting resource defensibility theory, which posits that land ownership is more likely where productivity is predictable. We find less support for a proposed link between agricultural intensification and land ownership. Overall, we demonstrate the value of combining analytical approaches from evolution and ecology to test diverse hypotheses on land ownership across a range of disciplines.1. Introduction 2. Materials and methods 2.1 Data 2.2 Phylogenetic analyses of evolution of land ownership 2.3 Multi-model inference of drivers of spatial patterns in land ownership 3. Results 3.1 Evolutionary trajectories of land ownership 3.2 Drivers of spatial variation in land ownership 4. Discussio

    Pathways to social inequality

    No full text
    Social inequality is now pervasive in human societies, despite the fact that humans lived in relatively egalitarian, small-scale societies across most of our history. Prior literature highlights the importance of environmental conditions, economic defensibility, and wealth transmission for shaping early Holocene origins of social inequality. However, it remains untested whether the mechanisms that drive the evolution of inequality in recent human societies follow a similar trajectory. We conduct the first global analysis of pathways to inequality within modern human societies using structural equation modeling. Our analytical approach demonstrates that environmental conditions, resource intensification, and wealth transmission mechanisms impact various forms of social inequality via a complex web of causality. We further find that subsistence practices have a direct impact on some institutionalized forms of inequality. This work identifies drivers of social inequality in the modern world and demonstrates the application of structural equation modeling methods to investigate complex relationships between elements of human culture

    Pathways to social inequality

    Get PDF
    Social inequality is now pervasive in human societies, despite the fact that humans lived in relatively egalitarian, small-scale societies across most of our history. Prior literature highlights the importance of environmental conditions, economic defensibility, and wealth transmission for shaping early Holocene origins of social inequality. However, it remains untested whether the mechanisms that drive the evolution of inequality in recent human societies follow a similar trajectory. We conduct the first global analysis of pathways to inequality within modern human societies using structural equation modeling. Our analytical approach demonstrates that environmental conditions, resource intensification, and wealth transmission mechanisms impact various forms of social inequality via a complex web of causality. We further find that subsistence practices have a direct impact on some institutionalized forms of inequality. This work identifies drivers of social inequality in the modern world and demonstrates the application of structural equation modeling methods to investigate complex relationships between elements of human culture

    Charmonium suppression in p-A collisions

    Get PDF
    The new high precision data on charmonium production in proton-nucleus collisions by the E866/NuSea collaboration at Fermilab allow - together with older data at lower energies - to fix a unique set of parameters for the standard production and absorption scenario of charmonium in a proton-nucleus reaction. In this scenario the c-cbar pair is formed in an octet state, emits a gluon and continues its radial expansion in a singlet state until it has reached the charmonium radius. In all three phases it can interact with the nuclear environment. We find that the lifetime of the octet state is much shorter than acceptable on physical grounds. This challenges the physical reality of the first phase in the standard scenario.Comment: 8 pages, 10 figure
    corecore