12,763 research outputs found

    Impact of ICARDA Research on Australian Agriculture

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    Research and Development/Tech Change/Emerging Technologies,

    Non-stationary stochastic optimization of an oscillating water column

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    A non-stationary stochastic optimization methodology is applied to an OWC (oscillating water column) to find the design that maximizes the wave energy extraction. Different temporal cycles are considered to represent the long-term variability of the wave climate at the site in the optimization problem. The results of the non-stationary stochastic optimization problem are compared against those obtained by a stationary stochastic optimization problem. The comparative analysis reveals that the proposed non-stationary optimization provides designs with a better fit to reality. However, the stationarity assumption can be adequate when looking at averaged system response

    A Coherent Through-Wall MIMO Phased Array Imaging Radar based on Time-Duplexed Switching

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    Through-the-Wall (TW) radar sensors are gaining increasing interest for security, surveillance and search and rescue applications. Additionally, the integration of Multiple-Input, Multiple-Output (MIMO) techniques with phased array radar is allowing higher performance at lower cost. In this paper we present a 4-by-4 TW MIMO phased array imaging radar operating at 2.4 GHz with 200 MHz bandwidth. To achieve high imaging resolution in a cost-effective manner, the 4 Tx and 4 Rx elements are used to synthesize a uniform linear array (ULA) of 16 virtual elements. Furthermore, the transmitter is based on a single-channel 4-element time-multiplexed switched array. In transmission, the radar utilizes frequency modulated continuous wave (FMCW) waveforms that undergo de-ramping on receive to allow digitization at relatively low sampling rates, which then simplifies the imaging process. This architecture has been designed for the short-range TW scenarios envisaged, and permits sufficient time to switch between antenna elements. The paper first outlines the system characteristics before describing the key signal processing and imaging algorithms which are based on traditional Fast Fourier Transform (FFT) processing. These techniques are implemented in LabVIEW software. Finally, we report results from an experimental campaign that investigated the imaging capabilities of the system and demonstrated the detection of personnel targets. Moreover, we show that multiple targets within a room with greater than approximately 1 meter separation can be distinguished from one another

    Laryngeal debridement: an alternative treatment for a laryngopyocele presenting with severe airway obstruction

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    The laryngocele is an abnormal saccular dilatation of the ventricle of Morgagni, which maintains its communication with the laryngeal vestibule. Three types of laryngoceles have been described: internal, external, and combined or mixed in relation to the position of the sac with respect to the thyrohyoid membrane. If the laryngocele becomes obstructed and infected it leads to the so-called laryngopyocele which, although a rare disease (8% of laryngoceles), can become an emergency causing severe airway obstruction needing urgent management, even tracheostomy. An alternative method is presented of emergency management of an internal laryngopyocele causing severe airway obstruction using a laryngeal microdebrider and avoiding tracheostomy

    Do (and say) as I say: Linguistic adaptation in human-computer dialogs

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    © Theodora Koulouri, Stanislao Lauria, and Robert D. Macredie. This article has been made available through the Brunel Open Access Publishing Fund.There is strong research evidence showing that people naturally align to each other’s vocabulary, sentence structure, and acoustic features in dialog, yet little is known about how the alignment mechanism operates in the interaction between users and computer systems let alone how it may be exploited to improve the efficiency of the interaction. This article provides an account of lexical alignment in human–computer dialogs, based on empirical data collected in a simulated human–computer interaction scenario. The results indicate that alignment is present, resulting in the gradual reduction and stabilization of the vocabulary-in-use, and that it is also reciprocal. Further, the results suggest that when system and user errors occur, the development of alignment is temporarily disrupted and users tend to introduce novel words to the dialog. The results also indicate that alignment in human–computer interaction may have a strong strategic component and is used as a resource to compensate for less optimal (visually impoverished) interaction conditions. Moreover, lower alignment is associated with less successful interaction, as measured by user perceptions. The article distills the results of the study into design recommendations for human–computer dialog systems and uses them to outline a model of dialog management that supports and exploits alignment through mechanisms for in-use adaptation of the system’s grammar and lexicon

    A new method for atmospheric detection of the CH3O2 radical

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    A new method for measurement of the methyl peroxy (CH3O2) radical has been developed using the conversion of CH3O2 into CH3O by excess NO with subsequent detection of CH3O by fluorescence assay by gas expansion (FAGE) with laser excitation at ca. 298 nm. The method can also directly detect CH3O, when no nitric oxide is added. Laboratory calibrations were performed to characterise the FAGE instrument sensitivity using the conventional radical source employed in OH calibration with conversion of a known concentration of OH into CH3O2 via reaction with CH4 in the presence of O2. Detection limits of 3.8 × 108 and 3.0 × 108 molecule cm−3 were determined for CH3O2 and CH3O respectively for a signal-to-noise ratio of 2 and 5 min averaging time. Averaging over 1 h reduces the detection limit for CH3O2 to 1.1 × 108 molecule cm−3, which is comparable to atmospheric concentrations. The kinetics of the second-order decay of CH3O2 via its self-reaction were observed in HIRAC (Highly Instrumented Reactor for Atmospheric Chemistry) at 295 K and 1 bar and used as an alternative method of calibration to obtain a calibration constant with overlapping error limits at the 1σ level with the result of the conventional method of calibration. The overall uncertainties of the two methods of calibrations are similar – 15 % for the kinetic method and 17 % for the conventional method – and are discussed in detail. The capability to quantitatively measure CH3O in chamber experiments is demonstrated via observation in HIRAC of CH3O formed as a product of the CH3O2 self-reaction

    Electron microscopical study to assess the in vitro effects of the synthetic trioxolane OZ78 against the liver fluke, Fasciola hepatica

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    Adult Fasciola hepatica were incubated for 48 h in vitro in the synthetic peroxide, OZ78 at a concentration of 100 μg/ml and then prepared for scanning and transmission electron microscopy. There was limited disruption to the external fluke surface, with only slight swelling and blebbing of the interspinal tegument in the midbody and ventral tail regions. By contrast, significant disruption was observed to the ultrastructure of the tegument and subtegumental tissues. There was severe swelling of the basal infolds in the tegumental syncytium and the flooding spread internally to affect the subtegumental tissues. In the tegumental system, there was swelling of the cisternae of granular endoplasmic reticulum and of the mitochondria, with the latter showing signs of breaking down. Autophagic vacuoles and lipid droplets were present and the synthesis of tegumental secretory bodies was much reduced. The gastrodermal cells were severely affected, with swelling and degeneration of the mitochondria and the presence of autophagic vacuoles and lipid droplets. The granular endoplasmic reticulum was swollen and vesiculated and the cells contained few secretory bodies. Both the vitelline and testis follicles showed evidence of extensive cellular disruption and degeneration. This study confirms previous data indicating the potential flukicidal activity of OZ7

    Knowledge, Attitudes, and Intentions Toward Fertility Awareness and Oocyte Cryopreservation Among Obstetrics and Gynecology Resident Physicians

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    STUDY QUESTION What knowledge, attitudes and intentions do US obstetrics and gynecology (OB/GYN) residents have toward discussing age-related fertility decline and oocyte cryopreservation with their patients? SUMMARY ANSWER Most OB/GYN residents believe that age-related fertility decline, but not oocyte cryopreservation, should be discussed during well-woman annual exams; furthermore, nearly half of residents overestimated the age at which female fertility markedly declines. WHAT IS KNOWN ALREADY Oocyte cryopreservation can be utilized to preserve fertility potential. Currently, no studies of US OB/GYN residents exist that question their knowledge, attitudes, and intentions toward discussing age-related fertility decline and oocyte cryopreservation with patients. STUDY DESIGN, SIZE, DURATION A cross-sectional online survey was conducted during the fall of 2014 among residents in American Council for Graduate (ACOG) Medical Education-approved OB/GYN residency programs. Program directors were emailed via the ACOG Council on Resident Education in Obstetrics and Gynecology server listing and asked to solicit resident participation. PARTICIPANTS/MATERIALS, SETTING, METHODS Participants included 238 residents evenly distributed between post-graduate years 1–4 with varied post-residency plans; 90% of residents were women and 75% were 26–30 years old. The survey was divided into three sections: demographics, fertility awareness, and attitudes toward discussing fertility preservation options with patients. Descriptive and inferential statistics were conducted. MAIN RESULTS AND THE ROLE OF CHANCE A strong majority of residents (83%) believed an OB/GYN should initiate discussions about age-related fertility decline with patients (mean patient age 31.8), and 73% percent believed these discussions should be part of an annual exam. One third of residents overestimated the age at which there is a slight decline in female fertility, while nearly half of residents overestimated the age at which female fertility markedly declines. Over three-quarters of residents (78.4%) also overestimated the likelihood of success using assisted reproductive treatments (ARTs). Residents were likely to support oocyte cryopreservation in cancer patients irrespective of the woman\u27s age, but much less likely to support elective oocyte cryopreservation. For elective oocyte cryopreservation, 40% believed OB/GYNs should initiate discussions with patients (mean age 31.1), while only 20% believed this topic should be part of an annual exam. LIMITATIONS, REASONS FOR CAUTION Because the study invitation was sent through US OB/GYN residency program directors rather than directly to residents, it is possible that some residents did not receive the invitation to participate. This limits the generalizability of the findings. WIDER IMPLICATIONS OF THE FINDINGS Within the USA, there appears to be a critical need for improved education on fertility decline in OB/GYN residency programs. To promote informed reproductive decision-making among patients, efforts should be made to help OB/GYNs provide comprehensive fertility education to all women, while also respecting patient choices
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