168 research outputs found

    A High Stability Optical Shadow Sensor with Applications for Precision Accelerometers

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    Gravimeters are devices which measure changes in the value of the gravitational acceleration, \textit{g}. This information is used to infer changes in density under the ground allowing the detection of subsurface voids; mineral, oil and gas reserves; and even the detection of the precursors of volcanic eruptions. A micro-electro mechanical system (MEMS) gravimeter has been fabricated completely in silicon allowing the possibility of cost e-effective, lightweight and small gravimeters. To obtain a measurement of gravity, a highly stable displacement measurement of the MEMS is required. This requires the development of a portable electronics system that has a displacement sensitivity of ā‰¤2.5\leq 2.5 nm over a period of a day or more. The portable electronics system presented here has a displacement sensitivity ā‰¤10\leq 10 nm/Hz/\sqrt{\textrm{Hz}} (ā‰¤0.6\leq 0.6 nm at 10001000 s). The battery power system used a modulated LED for measurements and required temperature control of the system to Ā±\pm 2 mK, monitoring of the tilt to Ā±\pm 2 Ī¼\muradians, the storage of measured data and the transmission of the data to an external server.Comment: 8 Pages, 12 figures, 5 equations, currently submitted and under review at IEEE Sensors SIE

    Boundedly rational expected utility theory

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    We build a satisficing model of choice under risk which embeds Expected Utility Theory (EUT) into a boundedly rational deliberation process. The decision maker accumulates evidence for and against alternative options by repeatedly sampling from her underlying set of EU preferences until the evidence favouring one option satisfies her desired level of confidence. Despite its EUT core, the model produces patterns of behaviour that violate standard EUT axioms, while at the same time capturing systematic relationships between choice probabilities, response times and confidence judgments, which are beyond the scope of theories that do not take deliberation into account

    Boundedly rational expected utility theory

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    We build a satisficing model of choice under risk which embeds Expected Utility Theory (EUT) into a boundedly rational deliberation process. The decision maker accumulates evidence for and against alternative options by repeatedly sampling from her underlying set of EU preferences until the evidence favouring one option satisfies her desired level of confidence. Despite its EUT core, the model produces patterns of behaviour that violate standard EUT axioms, while at the same time capturing systematic relationships between choice probabilities, response times and confidence judgments, which are beyond the scope of theories that do not take deliberation into account

    Objective methods of nerve localisation to facilitate performing locoregional anaesthetic techniques for horses undergoing surgical procedures

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    SummaryPerineural anaesthesia is a useful technique in equine surgery, providing preā€emptive targeted anaesthesia of the surgical site, reducing volatile anaesthetic requirements, improving recovery quality and providing postoperative pain relief. Surgery under standing sedation in horses has increased in popularity, mandating the need for effective locoregional anaesthesia and analgesic techniques. Nerve location techniques offer greater accuracy than blind techniques when placing injectate. These methods can help to avoid structures such as blood vessels and minimise direct nerve damage during needle placement, reducing the risk of procedureā€related complications. This review will discuss the most pertinent research in the veterinary literature where objective methods of nerve location have been used to perform peripheral nerve blocks in horses. The efficacy of using objective methods to perform nerve blocks in equine anaesthesia is discussed by the authors, providing useful information to equine anaesthetists, and potentially improve the quality of anaesthesia and analgesia in horses.</jats:p

    Boundedly Rational Expected Utility Theory

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    We build a satisficing model of probabilistic choice under risk which embeds Expected Utility Theory (EUT) into a boundedly rational deliberation process. The decision maker accumulates evidence for and against alternative options by repeatedly sampling from her underlying set of EU preferences until the evidence favouring one option satisfies her desired level of confidence. Notwithstanding its EUT core, the model produces patterns of behaviour that violate standard axioms, while at the same time capturing the systematic relationship between choice probabilities, response times and confidence judgments, which is beyond the scope of theories that do not take deliberation into account

    Switching energy suppliers: It's not all about the money

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    Many consumers do not take advantage of lower energy prices available in liberalized retail markets. We provide evidence to explain why consumers may leave substantial amounts of "money on the table" in this way. We observe real decisions made by over 7,000 consumers in a collective switching auction, supplemented by their responses to a survey. We identify factors which may inhibit switching and show that expectations of high switching rates in an unregulated market may be unrealistic. Our findings have important implications for the design and regulation of energy markets, including imposition of price caps on "default" retail tariffs in 2019 in the UK and parts of Australia

    Identification of PKD1L1 Gene Variants in Children with the Biliary Atresia Splenic Malformation Syndrome

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    Biliary atresia (BA) is the most common cause of endā€stage liver disease in children and the primary indication for pediatric liver transplantation, yet underlying etiologies remain unknown. Approximately 10% of infants affected by BA exhibit various laterality defects (heterotaxy) including splenic abnormalities and complex cardiac malformations ā€” a distinctive subgroup commonly referred to as the biliary atresia splenic malformation (BASM) syndrome. We hypothesized that genetic factors linking laterality features with the etiopathogenesis of BA in BASM patients could be identified through whole exome sequencing (WES) of an affected cohort. DNA specimens from 67 BASM subjects, including 58 patientā€parent trios, from the NIDDKā€supported Childhood Liver Disease Research Network (ChiLDReN) underwent WES. Candidate gene variants derived from a preā€specified set of 2,016 genes associated with ciliary dysgenesis and/or dysfunction or cholestasis were prioritized according to pathogenicity, population frequency, and mode of inheritance. Five BASM subjects harbored rare and potentially deleterious biā€allelic variants in polycystin 1ā€like 1, PKD1L1, a gene associated with ciliary calcium signaling and embryonic laterality determination in fish, mice and humans. Heterozygous PKD1L1 variants were found in 3 additional subjects. Immunohistochemical analysis of liver from the one BASM subject available revealed decreased PKD1L1 expression in bile duct epithelium when compared to normal livers and livers affected by other nonā€cholestatic diseases. Conclusion WES identified biā€allelic and heterozygous PKD1L1 variants of interest in 8 BASM subjects from the ChiLDReN dataset. The dual roles for PKD1L1 in laterality determination and ciliary function suggest that PKD1L1 is a new, biologically plausible, cholangiocyteā€expressed candidate gene for the BASM syndrome

    Salience and the disposition effect: Evidence from the introduction of "Cash-Outs" in betting markets

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    The disposition effect describes the tendency of investors to sell assets that have increased in value since purchase, and hold those that have not. We analyse the introduction of betting market ā€˜Cash-Outsā€™, which provide a continual update ā€“ and therefore increase the salience ā€“ of bettorsā€™ paper profits/losses on each bet. We find that the introduction of Cash-Out increased the disposition effect in this market, as punters sold their profitable bets with greater frequency than before. We do not, however, find that the disposition effect has any impact on asset prices, either before or after this intervention
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