34 research outputs found

    Real Time and High Fidelity Quadcopter Tracking System

    Get PDF
    This project was conceived as a desired to have an affordable, flexible and physically compact tracking system for high accuracy spatial and orientation tracking. Specifically, this implementation is focused on providing a low cost motion capture system for future research. It is a tool to enable the further creation of systems that would require the use of accurate placement of landing pads, payload acquires and delivery. This system will provide the quadcopter platform a coordinate system that can be used in addition to GPS. Field research with quadcopter manufacturers, photographers, agriculture and research organizations were contact and interviewed for information on what components of a quadcopter system were lacking and what barriers currently limited desired drone operation. Distilling this information and after exploring various projects in the field of quadcopter and autonomous control, the idea was found to develop a system that could track the motion of quadcopters to jump start other projects. Specifically, live feedback was explored to be used as hardware in the loop testing systems where commands are relayed to the quadcopter and its response can be accurately measured. This can be extremely beneficial in new equipment testing such as new propeller design, motor design, and frame response. A further stretch objective for this project is to unify input commands to the quadcopter with its physical position in order to train control systems to fly new platforms running “piloted” platforms such as BetaFlight, RaceFlight and KISS platforms typically associated with drone racing as well as hobby grade semi-autonomous flight controller such as ArduPilot Mega (APM) & PixHawk

    Plasticity in bilateral superior temporal cortex: effects of deafness and cochlear implantation on auditory and visual speech processing

    Get PDF
    While many individuals can benefit substantially from cochlear implantation, the ability to perceive and understand auditory speech with a cochlear implant (CI) remains highly variable amongst adult recipients. Importantly, auditory performance with a CI cannot be reliably predicted based solely on routinely obtained information regarding clinical characteristics of the CI candidate. This review argues that central factors, notably cortical function and plasticity, should also be considered as important contributors to the observed individual variability in CI outcome. Superior temporal cortex (STC), including auditory association areas, plays a crucial role in the processing of auditory and visual speech information. The current review considers evidence of cortical plasticity within bilateral STC, and how these effects may explain variability in CI outcome. Furthermore, evidence of audio-visual interactions in temporal and occipital cortices is examined, and relation to CI outcome is discussed. To date, longitudinal examination of changes in cortical function and plasticity over the period of rehabilitation with a CI has been restricted by methodological challenges. The application of functional near-infrared spectroscopy (fNIRS) in studying cortical function in CI users is becoming increasingly recognised as a potential solution to these problems. Here we suggest that fNIRS offers a powerful neuroimaging tool to elucidate the relationship between audio-visual interactions, cortical plasticity during deafness and following cochlear implantation, and individual variability in auditory performance with a CI

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

    Get PDF
    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    The 'others' amongst 'them' – selection categories in European resettlement and humanitarian admission programmes

    Get PDF
    The chapter looks at categorisations as a form of ‘othering’ in the context of European refugee resettlement. Selection categories in resettlement provide insights into states’ preferences, when given the possibility to effectively select refugees before they present themselves at the border. As such, categorisations in such programmes are ways of othering within the group of ‘others’, excluding but also including according to three logics: humanitarian, security and assimilability. The chapter provides a panoramic view of official selection categories of the United Nations High Commissioner for Refugees (UNHCR), European Member States, and the European Union (EU). The analysis shows that, while resettlement is framed as a humanitarian policy for the ‘most vulnerable’, some European states’ programmes and recent EU propositions indicate that besides a humanitarian logic, security and assimilability logics of ‘othering’ also draw the boundaries of access to this privileged form of refugee protection

    A Galactose Specific Agglutinin from the Hemolymph of the Snail Achatina Fulica : Purification and Characterization

    No full text
    galactose specific agglutinin has been detected in the hemolymph of the snail Achatina furl ca fulica Bowdich. The agglutinin, which agglutinates rabbit erythrocytes, has been purified by affinity chromatography on crosslinked guargum followed by gel filtration on a Biogel P-200 column. The purified agglutinin has a native molecular weight of 210,000 and comprises of non covalently linked identical subunits of molecular weight 15,000. The pI of the agglutinin was found to be g.1. The activity of the agglutinin is independent of divalent cations. The inhibition of hemagglutination data reveals that 2-deoxy- D-galactose is the most potent inhibitor of the agglutinin followed by galactose and lactose. INTR
    corecore