1,236 research outputs found

    Presenting in Virtual Worlds: Towards an Architecture for a 3D Presenter explaining 2D-Presented Information

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    Entertainment, education and training are changing because of multi-party interaction technology. In the past we have seen the introduction of embodied agents and robots that take the role of a museum guide, a news presenter, a teacher, a receptionist, or someone who is trying to sell you insurances, houses or tickets. In all these cases the embodied agent needs to explain and describe. In this paper we contribute the design of a 3D virtual presenter that uses different output channels to present and explain. Speech and animation (posture, pointing and involuntary movements) are among these channels. The behavior is scripted and synchronized with the display of a 2D presentation with associated text and regions that can be pointed at (sheets, drawings, and paintings). In this paper the emphasis is on the interaction between 3D presenter and the 2D presentation

    Temporal afterglow between two pulses of repetitively pulsed argon-acetylene plasma:measuring electron and negatively charged species densities

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    The temporal afterglow between two pulses of a repetitively pulsed radio-frequency driven low-pressure argon-acetylene plasma is experimentally explored using laser-induced photodetachment combined with microwave cavity resonance spectroscopy. The densities of electrons and negatively charged species, i.e. anions and dust particles, are measured temporally resolved until 1.9 s in the temporal plasma afterglow. Two different plasma-on times are adjusted to investigate the dynamics of anions and dust particles in the afterglow phase. The measurements show that while electrons decay rapidly within the first few milliseconds of the afterglow phase, the negatively charged species reside much longer in the plasma after the plasma is switched off. The electron density decay is measured to be faster for a longer plasma-on time. This effect is attributed to an enhanced recombination rate due to a higher dust particle density and/or size. The density of negatively charged species decays within two different timescales. The first 20 milliseconds of the afterglow is marked with a rapid decay in the negatively charged species density, in contrast with their slow density decay in the second time scale. Moreover, a residual of the negatively charged species densities is detected as long as 1.9 s after extinguishing the plasma.</p

    A novel diagnostic for dust particle size in a low-pressure nanodusty plasma based on the decay of the electron density released by laser-induced photodetachment

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    One of the key parameters in low-pressure nanodusty plasmas is the dust particle size. In this work, we introduce a new method for the determination of the dust particle size in a nanodusty plasma, created in a mixture of argon and hexamethyldisiloxane. To this end, an ultraviolet ( Ī» = 266 nm ) pulsed laser was used to release plasma-collected electrons from the nanoparticles. Subsequently, the response of the free electron density of the plasma was measured using microwave cavity resonance spectroscopy. Using a stochastic model for particle charging using orbital-motion limited (OML) theory, the predicted charging timescale can be directly compared to the experimentally measured decay timescale of the photo-released electron density. Good agreement was found between the experimentally predicted dust particle size and ex situ scanning electron microscopy (SEM) measurements. Furthermore, the sensitivity of the OML model to its input parameters was assessed. Finally, reversing the method can yield an estimate for the positive ion density based on the dust particle size from SEM.</p

    Spontaneous midgestation abortion associated with Bacteroides fragilis: a case report.

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    A midtrimester pregnancy loss, due to B. fragilis is described. We hypothesize that in early pregnancy anaerobic bacterial vaginosis has the greatest pathogenicity, while an intermediate (mixed) flora is most dangerous in midtrimester miscarriages, and that aerobic vaginitis is more dangerous than anaerobes towards the second half of the pregnancy. Unfortunately, no screen and treat policy has yet been proven to be sufficiently powerful to prevent the vast majority of infection-related prematurity. Ā© 2005 Taylor & Francis.status: publishe

    Lactobacillus crispatus as the etiological agent in cytolytic vaginosis

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    Introduction: Lactobacillus spp. dominate the vaginal niche but can also be involved in other vaginal dysbiosis, such as cytolytic vaginosis (CV), which remains poorly studied. It is characterized by a cryptic symptomatology, that often confounds the clinic. Goals: The aim of this work was to search for the etiological agent of CV, by studying the vaginal microbiome and metabolomics of women afflicted with this disease and compare it with women with other clinical diagnostic. Methods: Twenty-one vaginal washes have been collected from women attending a gynaecology consultation of a private clinic. The samples were categorized according with clinical diagnosis at the time of sampling (CV, 11; vulvovaginal candidosis, 8; Healthy, 2). The distribution of bacterial species, and their prevalence was assessed by next-generation sequencing of the 16S V4 region. In addition, total lactate D-lactic acid and L-lactic acid was quantified in all washes by a commercial kit, as well as lactate dehydrogenase (LDH) activity. Results: L. crispatus was dominant (>70%) in all CV samples. Lactate was increased in CV in comparison with other cases. The presence of D-lactic acid isomer was associated with presence of L. crispatus. LDH activity was increased in vaginal washes that tested positive for the presence of L. crispatus, however no direct association was found with CV cases. Discussion/Conclusions: The microbiome of women afflicted with CV was dominated in all cases by L. crispatus, contrarily with the results obtained for women diagnosed with other clinical symptomatology. In addition, the finding that an increase in D-lactic acid is associated with CV patients can be related to the role of L. crispatus in CV. The determination of LDH activity did not correlate exclusively with CV cases. On the other hand, D-lactic acid and total lactate quantification could be used as a valuable biomarker to diagnose this cryptic vaginal infection.info:eu-repo/semantics/publishedVersio

    Why did Donders, after describing pseudotorsion, deny the existence of ocular counterrolling together with Ruete, Volkmann, von Graefe and von Helmholtz, until Javal reconfirmed its existence?

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    After the rapid spread of strabismus surgery by total tenotomy, which had been proposed by the orthopedist Louis Stromeyer from Gƶttingen in 1838 and performed by the plastic surgeon Johann Friedrich Dieffenbach on October 26th and by the ophthalmologist Florent Cunier on October 29th, 1839, brilliant researchers studied the physiology of eye movements, resulting in the laws by Franciscus Cornelis Donders on pseudotorsion in tertiary positions of gaze and by Johann Benedict Listing that each eye position can be reached by rotation about an axis perpendicular to the primary and the new position of gaze. John Hunter had first described ocular counterrolling (OCR) with head tilt in 1786. The anatomist Alexander Friedrich von Hueck inferred from anatomical studies, however, that up to 28.6Ā° OCR would be possible onhead-tilt to right or left shoulder in 1838, and estimated his own OCR seen in a mirror at approximately 25Ā°. Donders, Christian Georg Theodor Ruete, Alfred Wilhelm Volkmann, Albrecht von Graefe and Hermann von Helmholtz subsequently denied the existence of OCR for many years and thought that only pseudotorsion existed. Louis Emile Javal had myopia and astigmatism, and he re-established the existence of OCR in 1867 when he noticed that, on head tilt to either shoulder, the axis of astigmatism of his eyes no longer coincided with the axis of astigmatism of his glasses

    Challenging medical students with an interim assessment: a positive effect on formal examination score in a randomized controlled study

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    Until now, positive effects of assessment at a medical curriculum level have not been demonstrated. This study was performed to determine whether an interim assessment, taken during a small group work session of an ongoing biomedical course, results in studentsā€™ increased performance at the formal course examination. A randomized controlled trial was set up, with an interim assessment without explicit feedback as intervention. It was performed during a regular biomedical Bachelor course of 4Ā weeks on General Pathology at the Radboud University Nijmegen Medical Centre. Participants were 326 medical and 91 biomedical science students divided into three study arms: arm Intervention-1 (I-1) receiving one interim assessment; arm I-2 receiving two interim assessments, and control arm C, receiving no interim assessment. The study arms were stratified for gender and study discipline. The interim assessment consisted of seven multiple-choice questions on tumour pathology. Main outcome measures were overall score of the formal examination (scale 1ā€“10), and the subscore of the questions on tumour pathology (scale 1ā€“10). We found that students who underwent an interim assessment (arm I) had a 0.29-point (scale 1ā€“10) higher score on the formal examination than the control group (pĀ =Ā 0.037). For the questions in the formal examination on tumour pathology the score amounted to 0.47 points higher (pĀ =Ā 0.007), whereas it was 0.17 points higher for the questions on topics related to the previous 3Ā weeks. No differences in formal examination score were found between arms I-1 and I-2 (pĀ =Ā 0.817). These findings suggest that an interim assessment during a small group work session in a randomized study setting stimulates students to increase their formal examination score

    Mateship and Money-Making: Shearing in Twentieth Century Australia

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    After the turmoil of the 1890s shearing contractors eliminated some of the frustration from shearers recruitment. At the same time closer settlement concentrated more sheep in small flocks in farming regions, replacing the huge leasehold pastoral empires which were at the cutting edge of wool expansion in the nineteenth century. Meanwhile the AWU succeeded in getting an award for the pastoral industry under the new arbitration legislation in 1907. Cultural and administrative influences, therefore, eased some of the bitter enmity which had made the annual shearing so unstable. Not all was plain sailing. A pattern of militancy re-emerged during World War I. Shearing shed unrest persisted throughout the interwar period and during World War II. In the 1930s a rival union with communist connections, the PWIU, was a major disruptive influence. Militancy was a factor in a major shearing strike in 1956, when the boom conditions of the early-1950s were beginning to fade. The economic system did not have satisfactory mechanisms to cope. Unionised shearers continued to be locked in a psyche of confrontation as wool profits eroded further in the 1970s. This ultimately led to the wide comb dispute, which occurred as wider pressures changed an economic order which had not been seriously challenged since Federation, and which the AWU had been instrumental in shaping. Shearing was always identified with bushworker ā€˜mateshipā€™, but its larrikinism and irreverence to authority also fostered individualism, and an aggressive ā€˜moneymakingā€™ competitive culture. Early in the century, when old blade shearers resented the aggressive pursuit of tallies by fast men engaged by shearing contractors, tensions boiled over. While militants in the 1930s steered money-makers into collectivist versions of mateship, in the farming regions the culture of self-improvement drew others towards the shearing competitions taking root around agricultural show days. Others formed their own contracting firms and had no interest in confrontation with graziers. Late in the century New Zealanders arrived with combs an inch wider than those that had been standard for 70 years. It was the catalyst for the assertion of meritocracy over democracy, which had ruled since Federation
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