61 research outputs found

    Increasing Response Effort Impacts Wager Sizes of Slot- Machine Gamblers

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    The current study investigated the effects of the physical location of the “Bet Max” wager button on a slot machine on 29 recreational gamblers. Distance from the Spin button varied across three groups of gamblers ranging from 9.52mm to 111.12mm. The results indicated a significant change in bet allocation between groups, mainly, greater distance between the Max Bet button and Spin button resulted in fewer responses allocated to the Max Bet button. Implications of the results are discussed in regards to response effort, and gambling device design

    Ring electrode for radio-frequency heating of the cornea: modelling and in vitro experiments

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    [EN] Radio-frequency thermokeratoplasty (RF-TKP) is a technique used to reshape the cornea curvature by means of thermal lesions using radio-frequency currents. This curvature change allows refractive disorders such as hyperopia to be corrected. A new electrode with ring geometry is proposed for RF-TKP. It was designed to create a single thermal lesion with a full-circle shape. Finite element models were developed, and the temperature distributions in the cornea were analysed for different ring electrode characteristics. The computer results indicated that the maximum temperature in the cornea was located in the vicinity of the ring electrode outer perimeter, and that the lesions had a semi-torus shape. The results also indicated that the electrode thickness, electrode radius and electrode thermal conductivity had a significant influence on the temperature distributions. In addition, in vitro experiments were performed on rabbit eyes. At 5 IN power the lesions were fully circular. Some lesions showed non-uniform characteristics along their circular path. Lesion depth depended on heating duration (60% of corneal thickness for 20s, and 30% for 10s). The results suggest that the critical shrinkage temperature (55-63degreesC) was reached at the central stroma and along the entire circular path in all the cases.Berjano, E.; Saiz Rodríguez, FJ.; Alió, J.; Ferrero, JM. (2003). Ring electrode for radio-frequency heating of the cornea: modelling and in vitro experiments. Medical & Biological Engineering & Computing. 41(6):630-639. https://doi.org/10.1007/BF02349970S630639416Alió, J. L., Ismail, M. M., Artola, A., andPérez-Santonja, J. J. (1997a): ‘Correction of hyperopia induced by photorefractive keratectomy using non-contact Ho: YAG laser thermal keratoplasty’,J. Refract. Surg.,13, pp. 13–16Alió, J. L., Ismail, M. M., andSanchez, J. L. (1997b): ‘Correction of hyperopia with non-contact Ho: YAG laser thermal keratoplasty’,J. Refract. Surg.,13, pp. 17–22Alió, J. 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    Oocyte Development, Meiosis and Aneuploidy

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    AbstractMeiosis is one of the defining events in gametogenesis. Male and female germ cells both undergo one round of meiotic cell division during their development in order to reduce the ploidy of the gametes, and thereby maintain the ploidy of the species after fertilisation. However, there are some aspects of meiosis in the female germline, such as the prolonged arrest in dictyate, that appear to predispose oocytes to missegregate their chromosomes and transmit aneuploidies to the next generation. These maternally-derived aneuploidies are particularly problematic in humans where they are major contributors to miscarriage, age-related infertility, and the high incidence of Down's syndrome in human conceptions. This review will discuss how events that occur in foetal oocyte development and during the oocytes’ prolonged dictyate arrest can influence meiotic chromosome segregation and the incidence of aneuploidy in adult oocytes

    Establishment of a 3D In Vitro Model to Accelerate the Development of Human Therapies against Corneal Diabetes

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    The authors thank Dr. John M Asara, Min Yuan, and Susanne Breitkopf for their technical help with metabolomics experiments, Dr. Ben Fowler for his technical help with TEM experiments and also Tina B McKay for many thoughtful discussions and scientific insights during the study.Purpose To establish an in vitro model that would mirror the in vivo corneal stromal environment in diabetes (DM) patients. Methods Human corneal fibroblasts from Healthy (HCFs), Type 1DM (T1DM) and Type 2DM (T2DM) donors were isolated and cultured for 4 weeks with Vitamin C stimulation in order to allow for extracellular matrix (ECM) secretion and assembly. Results Our data indicated altered cellular morphology, increased cellular migration, increased ECM assembly, and severe mitochondrial damage in both T1DM and T2DMs when compared to HCFs. Furthermore, we found significant downregulation of Collagen I and Collagen V expression in both T1DM and T2DMs. Furthermore, a significant up regulation of fibrotic markers was seen, including α-smooth muscle actin in T2DM and Collagen III in both T1DM and T2DMs. Metabolic analysis suggested impaired Glycolysis and Tricarboxylic acid cycle (TCA) pathway. Conclusion DM has significant effects on physiological and clinical aspects of the human cornea. The benefits in developing and fully characterizing our 3D in vitro model are enormous and might provide clues for the development of novel therapeutics.Yeshttp://www.plosone.org/static/editorial#pee

    Design restrictions and licensing for Petite Amateur Navy Satellite (PANSAT)

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    The small, inexpensive Petite Amateur Navy SATellite (PANSAT) is the Naval Postgraduate School (NPS) Space Systems Academic Group's first experience with real-time space operations. Propelled by the success of PANSAT, NPS will follow this project with more complex space systems such as ORION. This thesis discusses the general and specific design considerations and constraints encountered during the design of PANSAT, along with providing descriptions of the satellite's various subsystems. The study also addresses the problems and procedures associated with obtaining a license frequency assignment for PANSAT. Three viable licensing options, an amateur, a military and an experimental option are presented. The thesis also includes a detailed description of the national and international frequency regulatory agencies, for better understanding of the licensing procedures.http://archive.org/details/designrestrictio1094534930Captain, United States Marine CorpsApproved for public release; distribution is unlimited

    An Internal and Critical Review of the PEAK Relational Training System for Children with Autism and Related Intellectual Disabilities: 2014-2017

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    The PEAK Relational Training System was designed as an assessment instrument and treatment protocol for addressing language and cognitive deficits in children with autism. PEAK contains four comprehensive training modules: Direct Training and Generalization emphasize a contingency-based framework of language development, and Equivalence and Transformation emphasize an approach to language development consistent with Relational Frame Theory. The present paper provides a comprehensive and critical review of peer-reviewed publications based on the entirety PEAK system through April, 2017. We describe both psychometric and outcome research, and indicate both positive features and limitations of this body of work. Finally, we note several research and practice questions that remain to be answered with the PEAK curriculum as well as other many other autism assessment and treatment protocols that are rooted within the framework of applied behavior analysis
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