2,569 research outputs found

    Analysis of dynamic systems with DAP4H computer program

    Get PDF
    Dynamic Analysis Program, FORTRAN 4 Level H /DAP4H/, developed from 27 subprograms, features liberal use of the subroutines, subprograms, and skeletonization to minimize programming effort in formulating models of new systems and components. It formulates mathematical models of complex mechanical, pneumatic, and hydraulic dynamic systems

    Raddoppiamento sintattico and glottalization phenomena in Italian

    Get PDF
    This paper is a preliminary phonetic exploration of aspects of the well-known Italian sandhi phenomenon of Raddoppiamento sintattico (henceforth RS), which involves the gemination of word-initial consonants under certain conditions, eg dei [k]ani ‘some dogs’ but tre [kk]ani ‘three dogs’. It is often assumed that RS C-gemination is regular, but there is increasing evidence that it competes with other phenomena such as vowel lengthening. This paper first discusses results of our auditory study of RS contexts, which show that RS is far less frequent in spontaneous speech than is theoretically predicted. This paper then looks specifically at glottal stop insertion and creak in RS contexts, based on the results of an initial small-scale acoustic investigation. The first has controversially been reported as occurring in RS environments where it serves to block RS (Absalom & Hajek, 1997). In addition, glottal stops have also been claimed to provide a coda to short word-final stressed vowels outside of RS environments (Vayra, 1994). We discuss our unexpected finding that glottalization characterizes phrase boundaries in our spontaneous speech data, and the implications that this evidence may have for the phonetic and phonological description of Italian and for our understanding of RS

    A Typology of Spreading, Insertion and Deletion or What You Weren’t Told About Raddoppiamento Sintattico in Italian

    Get PDF
    This paper focuses on the description and analysis of the external sandhi phenomenon of raddoppiamento sintattico (hereafter RS) in Italian, sometimes referred to as word-initial gemination, for example: (1) No RS due cani [duùe kaùni] ‘two dogs

    Pharmacokinetic models for propofol-defining and illuminating the devil in the detail

    Get PDF
    The recently introduced open-target-controlled infusion (TCI) systems can be programmed with any pharmacokinetic model, and allow either plasma- or effect-site targeting. With effect-site targeting the goal is to achieve a user-defined target effect-site concentration as rapidly as possible, by manipulating the plasma concentration around the target. Currently systems are pre-programmed with the Marsh and Schnider pharmacokinetic models for propofol. The former is an adapted version of the Gepts model, in which the rate constants are fixed, whereas compartment volumes and clearances are weight proportional. The Schnider model was developed during combined pharmacokinetic-pharmacodynamic modelling studies. It has fixed values for V1, V3, k(13), and k(31), adjusts V2, k(12), and k(21) for age, and adjusts k(10) according to total weight, lean body mass (LBM), and height. In plasma targeting mode, the small, fixed V1 results in very small initial doses on starting the system or on increasing the target concentration in comparison with the Marsh model. The Schnider model should thus always be used in effect-site targeting mode, in which larger initial doses are administered, albeit still smaller than for the Marsh model. Users of the Schnider model should be aware that in the morbidly obese the LBM equation can generate paradoxical values resulting in excessive increases in maintenance infusion rates. Finally, the two currently available open TCI systems implement different methods of effect-site targeting for the Schnider model, and in a small subset of patients the induction doses generated by the two methods can differ significantly

    Crowd-Sourcing Fuzzy and Faceted Classification for Concept Search

    Full text link
    Searching for concepts in science and technology is often a difficult task. To facilitate concept search, different types of human-generated metadata have been created to define the content of scientific and technical disclosures. Classification schemes such as the International Patent Classification (IPC) and MEDLINE's MeSH are structured and controlled, but require trained experts and central management to restrict ambiguity (Mork, 2013). While unstructured tags of folksonomies can be processed to produce a degree of structure (Kalendar, 2010; Karampinas, 2012; Sarasua, 2012; Bragg, 2013) the freedom enjoyed by the crowd typically results in less precision (Stock 2007). Existing classification schemes suffer from inflexibility and ambiguity. Since humans understand language, inference, implication, abstraction and hence concepts better than computers, we propose to harness the collective wisdom of the crowd. To do so, we propose a novel classification scheme that is sufficiently intuitive for the crowd to use, yet powerful enough to facilitate search by analogy, and flexible enough to deal with ambiguity. The system will enhance existing classification information. Linking up with the semantic web and computer intelligence, a Citizen Science effort (Good, 2013) would support innovation by improving the quality of granted patents, reducing duplicitous research, and stimulating problem-oriented solution design. A prototype of our design is in preparation. A crowd-sourced fuzzy and faceted classification scheme will allow for better concept search and improved access to prior art in science and technology

    Alpha9 nicotinic acetylcholine receptors and the treatment of pain

    Get PDF
    Chronic pain is a vexing worldwide problem that causes substantial disability and consumes significant medical resources. Although there are numerous analgesic medications, these work through a small set of molecular mechanisms. Even when these medications are used in combination, substantial amounts of pain often remain. It is therefore highly desirable to develop treatments that work through distinct mechanisms of action. While agonists of nicotinic acetylcholine receptors (nAChRs) have been intensively studied, new data suggest a role for selective antagonists of nAChRs. α-Conotoxins are small peptides used offensively by carnivorous marine snails known as Conus. A subset of these peptides known as α-conotoxins RgIA and Vc1.1 produces both acute and long lasting analgesia. In addition, these peptides appear to accelerate the recovery of function after nerve injury, possibly through immune mediated mechanisms. Pharmacological analysis indicates that RgIA and Vc1.1 are selective antagonists of α9α10 nAChRs. A recent study also reported that these α9α10 antagonists are also potent GABA-B agonists. In the current study, we were unable to detect RgIA or Vc1.1 binding to or action on cloned GABA-B receptors expressed in HEK cells or Xenopus oocytes. We review the background, findings and implications of use of compounds that act on α9* nAChRs.11* indicates the possible presence of additional subunits.Fil: McIntosh, J. Michael. University of Utah; Estados UnidosFil: Absalom, Nathan. The University of Sydney; AustraliaFil: Chebib, Mary. The University of Sydney; AustraliaFil: Elgoyhen, Ana Belen. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Farmacología; ArgentinaFil: Vincler, Michelle. Wake Forest University Health Sciences; Estados Unido

    Volatile anaesthetics and positive pressure ventilation reduce left atrial performance: a transthoracic echocardiographic study in young healthy adults

    Get PDF
    Background Animal and in vitro studies suggest that volatile anaesthetics affect left atrial (LA) performance. We hypothesized that human LA pump function and dimensions are altered by volatile anaesthetics in vivo. Methods We performed transthoracic echocardiographic (TTE) measurements in 59 healthy subjects (aged 18-48 yr) undergoing minor surgery under general anaesthesia. The unpremedicated patients were randomly assigned to anaesthesia with sevoflurane, desflurane, or isoflurane. TTE examinations were performed at baseline and after induction of anaesthesia and upon placement of a laryngeal mask during spontaneous breathing. After changing to intermittent positive pressure ventilation (IPPV), an additional TTE was performed. The study focused on the velocity-time integral of late peak transmitral inflow velocity (AVTI) and maximum LA volume. Results We found no evidence for relevant differences in the effects of the three volatile anaesthetics. AVTI decreased significantly from 4.1 (1.2) cm at baseline to 3.2 (1.1) cm during spontaneous breathing of 1 minimum alveolar concentration of volatile anaesthetics. AVTI decreased further to 2.8 (1.0) cm after changing to IPPV. The maximum LA volume was 45.4 (18.6) cm3 at baseline and remained unchanged during spontaneous breathing but decreased to 34.5 (16.7) cm3 during IPPV. Other parameters of LA pump function and dimensions decreased similarly. Conclusions Volatile anaesthetics reduced active LA pump function in humans in vivo. Addition of IPPV decreased LA dimensions and further reduced LA pump function. Effects in vivo were less pronounced than previously found in in vitro and animal studies. Further studies are warranted to evaluate the clinical implications of these findings. Clinical trial registration NCT002445

    L'email per imparare l'italiano: aspetti linguistici e contenutistici della comunicazione telematica in italiano L2

    Get PDF
    The integration of electronic communication into the teaching and learning of languages has opened up new horizons. This paper discusses a project involving the use of email exchanges in the Italian program at the Australian National University. Approximately eighty students participated in the project which consisted of two iterations of a one-to-one email conversation. This article examines the language and content of the messages constructed by students in terms of the following features: -the implications of the physical, psychological and temporal distance inherent in email communication -the differences between email communication of native speakers and learners -the dialogic nature of email communication and its relationship to both written and spoken communication -the importance of “empty” messages -the creativity of expression and the relationship between form and content
    corecore