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Eye-tracking the emergence of attentional anchors in a mathematics learning tablet activity
Little is known about micro-processes by which sensorimotor interaction gives rise to conceptual development. Per embodiment theory, these micro-processes are mediated by dynamical attentional structures. Accordingly this study investigated eye-gaze behaviors during engagement in solving tablet-based bimanual manipulation tasks designed to foster proportional reasoning. Seventy-six elementary- and vocational-school students (9-15 yo) participated in individual task-based clinical interviews. Data gathered included action-logging, eye-tracking, and videography. Analyses revealed the emergence of stable eye-path gaze patterns contemporaneous with first enactments of effective manipulation and prior to verbal articulations of manipulation strategies. Characteristic gaze patterns included consistent or recurring attention to screen locations that bore non-salient stimuli or no stimuli at all yet bore invariant geometric relations to dynamical salient features. Arguably, this research validates empirically hypothetical constructs from constructivism, particularly reflective abstraction
Demonstration of Optical Nonlinearity in InGaAsP/InP Passive Waveguides
We report on the study of the third-order nonlinear optical interactions in
InGaAsP/InP strip-loaded waveguides. The material
composition and waveguide structures were optimized for enhanced nonlinear
optical interactions. We performed self-phase modulation, four-wave mixing and
nonlinear absorption measurements at the pump wavelength 1568 nm in our
waveguides. The nonlinear phase shift of up to has been observed in
self-phase modulation experiments. The measured value of the two-photon
absorption coefficient was 15 cm/GW. The four-wave mixing conversion
range, representing the wavelength difference between maximally separated
signal and idler spectral components, was observed to be 45 nm. Our results
indicate that InGaAsP has a high potential as a material platform for nonlinear
photonic devices, provided that the operation wavelength range outside the
two-photon absorption window is selected
The thickness of pitch: Crossmodal metaphors in Farsi, Turkish and Zapotec
Speakers use vocabulary for spatial verticality and size to describe pitch. A high–low contrast is common to many languages, but others show contrasts like thick–thin and big–small. We consider uses of thick for low pitch and thin for high pitch in three languages: Farsi, Turkish, and Zapotec. We ask how metaphors for pitch structure the sound space. In a language like English, high applies to both high-pitched as well as high-amplitude (loud) sounds; low applies to low-pitched as well as low-amplitude (quiet) sounds. Farsi, Turkish, and Zapotec organize sound in a different way. Thin applies to high pitch and low amplitude and thick to low pitch and high amplitude. We claim that these metaphors have their sources in life experiences. Musical instruments show co-occurrences of higher pitch with thinner, smaller objects and lower pitch with thicker, larger objects. On the other hand bodily experience can ground the high–low metaphor. A raised larynx produces higher pitch and lowered larynx lower pitch. Low-pitched sounds resonate the chest, a lower place than highpitched sounds. While both patterns are available from life experience, linguistic experience privileges one over the other, which results in differential structuring of the multiple dimensions of sound
More oxygen during development enhanced flight performance but not thermal tolerance of Drosophila melanogaster
High temperatures can stress animals by raising the oxygen demand above the oxygen supply. Consequently, animals under hypoxia could be more sensitive to heating than those exposed to normoxia. Although support for this model has been limited to aquatic animals, oxygen supply might limit the heat tolerance of terrestrial animals during energetically demanding activities. We evaluated this model by studying the flight performance and heat tolerance of flies (Drosophila melanogaster) acclimated and tested at different concentrations of oxygen (12%, 21%, and 31%). We expected that flies raised at hypoxia would develop into adults that were more likely to fly under hypoxia than would flies raised at normoxia or hyperoxia. We also expected flies to benefit from greater oxygen supply during testing. These effects should have been most pronounced at high temperatures, which impair locomotor performance. Contrary to our expectations, we found little evidence that flies raised at hypoxia flew better when tested at hypoxia or tolerated extreme heat better than did flies raised at normoxia or hyperoxia. Instead, flies raised at higher oxygen levels performed better at all body temperatures and oxygen concentrations. Moreover, oxygen supply during testing had the greatest effect on flight performance at low temperature, rather than high temperature. Our results poorly support the hypothesis that oxygen supply limits performance at high temperatures, but do support the idea that hyperoxia during development improves performance of flies later in life
Tribological challenges of scaling up tidal turbine blades
Generating electricity from renewable resources (wind, wave and tidal) is of increasing interest. Of all marine renewables, tidal energy, by comparison, possesses the higher persistency and predictability over long time scales and the higher density of water than air results in greater power output from a tidal turbine than a wind turbine with similar dimensions. However, due to the nature of the tides, developing a reliable device for such environments, especially with an increased rotor diameter, raises more challenges to be addressed including the tribological challenges such as sediment erosion, cavitation erosion and their possible synergistic effects on the tidal turbine blades. This research focuses on testing and developing materials for improved tribological performance in tidal environments. This includes producing a variety of composite materials with different fibres and layouts reinforcement to evaluate two main tribological issues of composite materials in tidal environments: matrix cutting and reinforcement fracture using a loped test rig, which measures the effects of impact angle, particle size and concentrations at different tip speeds. The test samples are analysed using scanning electron microscopy (SEM) to conduct a surface topography and characterisation
Mapping synergy of erosion mechanisms of tidal turbine composite materials in sea water conditions
Tidal energy, of all marine renewables energy, possesses higher persistency and predictability over long time scales. Moreover, the higher density of water than air also results in greater power output from a tidal turbine than a wind turbine with similar dimensions. Due to the aggressive marine environment, there are barriers in the development of tidal power generation technology. In particular, with regard to increased rotor diameter, the selection of material presents significant challenges to be addressed including the tribological environment, such as solid particle erosion, cavitation erosion, the effect of high thrust loading on the turbine blade tips, and the synergy between sea water conditions and such tribological phenomena. This research focuses on producing and testing a variety of composite materials with different fibres and reinforcement layouts to evaluate two main tribological issues in tidal environments: matrix cutting and reinforcement fracture. A slurry pot test rig was used to measures the effects of different impact angles and particles sizes at constant tip speeds
Why Do People Undergo THR and What Do They Expect to Gain—A Comparison of the Views of Patients and Health Care Professionals
Little concerted effort has been made to understand why individuals undergo total hip replacement (THR) surgery and their rehabilitation goals. Similarly, insight of views and perspective of health care professionals’ (HCPs) regarding surgery and what objective measures help them with decision-making is lacking. This patient and public involvement report aimed to explore both patients’ and HCPs’ perspectives of THR surgery. Twenty patients, 10 pre-THR, 10 post-THR, 9 physiotherapists, and 6 surgeons took part. Results suggest a consensus among patients and HCPs on pain reduction being the main reason for undergoing THR. The inability to carry out simple daily activities such as dog walking and sleep deprivation had a significant effect on patients’ mental and physical well-being. This article is the first to explore the views of THR patients and HCPs on reasons behind THR surgery amalgamated into a single report. As walking is important, wearable activity monitors are suggested as a possible motivator to enhance patient compliance to self-care rehabilitation and increase quality of life. A future research project on the use of such wearable activity monitors in enhancing mobility post-THR is therefore planned
Mathematic literacy of students in 9th grade: Research based on the PISA study test
Background and Objective:In workplaces, employees need to understand the meaning of the calculations they perform in their work environment, and in fact employers expect a desirable level of mathematical application from their employees. Education is obliged to train students as useful citizens for the society in proportion to the progress of science and technology. The question is whether a student, after compulsory education, is able to face everyday challenges or not. In many educational societies, this readiness and ability is called literacy, and in particular mathematical literacy. In other words, mathematical literacy includes applications of mathematics in relation to real life. Also, the National Council of Mathematics Teachers has stated that one of the most important goals of mathematics education is to make students aware of the role of mathematics and its effectiveness in life and development of thinking and reasoning; in addition, having confidence in their capacities and abilities in performing mathematical tasks and various problem-solving situations. The purpose of this study is to study the mathematical literacy of students in grade 9. Methods:The research is descriptive and survey method. The statistical population is 9th grade students of the junior high school in Najaf-Abad city and the sample consists of 266 male and female students selected randomly by cluster sampling method. The instrument for measuring is a researcher-made test based on the PISA study, which included 8 questions and included 14 questions. Student's mathematical literacy was studied in various fields and content areas using mathematical processes. The formal and content validity of the research tool was confirmed by experts in mathematical education and mathematical professors. Findings:The results showed that students did not perform well in mathematical literacy test. The findings indicate that the student's mathematical world is far from all aspects of issues, content areas, and mathematical processes with the real world. It is hoped that the results of this study will lead to a review of textbooks, teacher training and evaluation methods aimed at improving students' mathematical literacy so that students are more likely to come to the math class. Conclusion: However, for the progress and development of a society, citizens need to be dynamic and successful in their personal lives and have the ability to solve their personal problems. The expectation from a 15-year-old student is that he or she be able to make financial decisions for his or her personal purchases, for example, or that he or she be able to meet the personal needs of the profits from the purchase and sale of goods. Given that education professionals believe that students need both the components of communication skills and problem-solving ability to enter academia and the job market, and that these two are important through enhanced mathematical literacy, Addressing students' poor performance in assessing math literacy is not without merit.  ===================================================================================== COPYRIGHTS ©2019 The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, as long as the original authors and source are cited. No permission is required from the authors or the publishers. ====================================================================================
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