5,880 research outputs found

    The New Zealand Strong Motion Earthquake Recorder Network

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    The network of strong-motion earthquake recorders, maintained throughout New Zealand by the Engineering Seismology Section of the Department of Scientific and Industrial Research, is described. The instruments are either deployed as ground instruments to measure potential earthquake attack on structures, or in structures, e.g. buildings, dams and industrial installations, to record structural response. Details are given of installation of instruments , maintenance, laboratory work, record retrieval and digitisation, costs and staffing for the network. Future developments mooted include an improved digitising system, the introduction of an improved version of the existing mechanical-optical instrument in 1979, and, in the long term, the introduction of an entirely new digital recorder, having an electrical output from its accelerometers, which will make possible the transmission of data by telephone or radio link

    A model of large volumetric capacitance in graphene supercapacitors based on ion clustering

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    Electric double layer supercapacitors are promising devices for high-power energy storage based on the reversible absorption of ions into porous, conducting electrodes. Graphene is a particularly good candidate for the electrode material in supercapacitors due to its high conductivity and large surface area. In this paper we consider supercapacitor electrodes made from a stack of graphene sheets with randomly-inserted "spacer" molecules. We show that the large volumetric capacitances C > 100 F/cm^3 observed experimentally can be understood as a result of collective intercalation of ions into the graphene stack and the accompanying nonlinear screening by graphene electrons that renormalizes the charge of the ion clusters.Comment: 13 pages, 5 figures; additional discussion and supporting calculations adde

    Unbiased bases (Hadamards) for 6-level systems: Four ways from Fourier

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    In quantum mechanics some properties are maximally incompatible, such as the position and momentum of a particle or the vertical and horizontal projections of a 2-level spin. Given any definite state of one property the other property is completely random, or unbiased. For N-level systems, the 6-level ones are the smallest for which a tomographically efficient set of N+1 mutually unbiased bases (MUBs) has not been found. To facilitate the search, we numerically extend the classification of unbiased bases, or Hadamards, by incrementally adjusting relative phases in a standard basis. We consider the non-unitarity caused by small adjustments with a second order Taylor expansion, and choose incremental steps within the 4-dimensional nullspace of the curvature. In this way we prescribe a numerical integration of a 4-parameter set of Hadamards of order 6.Comment: 5 pages, 2 figure

    Game On? Smoking Cessation Through the Gamification of mHealth: A Longitudinal Qualitative Study

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    BACKGROUND: Finding ways to increase and sustain engagement with mHealth interventions has become a challenge during application development. While gamification shows promise and has proven effective in many fields, critical questions remain concerning how to use gamification to modify health behavior. OBJECTIVE: The objective of this study is to investigate how the gamification of mHealth interventions leads to a change in health behavior, specifically with respect to smoking cessation. METHODS: We conducted a qualitative longitudinal study using a sample of 16 smokers divided into 2 cohorts (one used a gamified intervention and the other used a nongamified intervention). Each participant underwent 4 semistructured interviews over a period of 5 weeks. Semistructured interviews were also conducted with 4 experts in gamification, mHealth, and smoking cessation. Interviews were transcribed verbatim and thematic analysis undertaken. RESULTS: Results indicated perceived behavioral control and intrinsic motivation acted as positive drivers to game engagement and consequently positive health behavior. Importantly, external social influences exerted a negative effect. We identified 3 critical factors, whose presence was necessary for game engagement: purpose (explicit purpose known by the user), user alignment (congruency of game and user objectives), and functional utility (a well-designed game). We summarize these findings in a framework to guide the future development of gamified mHealth interventions. CONCLUSIONS: Gamification holds the potential for a low-cost, highly effective mHealth solution that may replace or supplement the behavioral support component found in current smoking cessation programs. The framework reported here has been built on evidence specific to smoking cessation, however it can be adapted to health interventions in other disease categories. Future research is required to evaluate the generalizability and effectiveness of the framework, directly against current behavioral support therapy interventions in smoking cessation and beyond

    Menstrual phase influences cerebrovascular responsiveness in females but may not affect sex differences

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    Background and aims: Sex differences in the rate and occurrence of cerebrovascular diseases (e.g., stroke) indicate a role for female sex hormones (i.e., oestrogen and progesterone) in cerebrovascular function and regulation. However, it remains unclear how cerebrovascular function differs between the sexes, and between distinct phases of the menstrual cycle. This study aimed to compare cerebrovascular-CO(2) responsiveness in 1) females during the early follicular (EF), ovulatory (O) and mid-luteal (ML) phases of their menstrual cycle; and 2) males compared to females during phases of lower oestrogen (EF) and higher oestrogen (O). Methods: Eleven females (25 ± 5 years) complete experimental sessions in the EF (n = 11), O (n = 9) and ML (n = 11) phases of the menstrual cycle. Nine males (22 ± 3 years) completed two experimental sessions, approximately 2 weeks apart for comparison to females. Middle and posterior cerebral artery velocity (MCAv, PCAv) was measured at rest, during two stages of hypercapnia (2% and 5% CO(2) inhalation) and hypocapnia (voluntary hyperventilation to an end-tidal CO(2) of 30 and 24 mmHg). The linear slope of the cerebral blood velocity response to changes in end-tidal CO(2) was calculated to measure cerebrovascular-CO(2) responsiveness.. Results: In females, MCAv-CO(2) responsiveness to hypocapnia was lower during EF (−.78 ± .45 cm/s/mmHg) when compared to the O phase (−1.17 ± .52 cm/s/mmHg; p < .05) and the ML phase (−1.30 ± .82; p < .05). MCAv-CO(2) responsiveness to hypercapnia and hypo-to-hypercapnia, and PCAv-CO(2) responsiveness across the CO(2) range were similar between menstrual phases (p ≥ .20). MCAv-CO(2) responsiveness to hypo-to hypercapnia was greater in females compared to males (3.12 ± .91 cm/s/mmHg vs. 2.31 ± .46 cm/s/mmHg; p = .03), irrespective of menstrual phase (EF or O). Conclusion: Females during O and ML phases have an enhanced vasoconstrictive capacity of the MCA compared to the EF phase. Additionally, biological sex differences can influence cerebrovascular-CO(2) responsiveness, dependent on the insonated vessel

    Exercise as a Treatment for Peripheral Vascular Dysfunction Caused by Metabolic Syndrome and Depression

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    Please refer to the pdf version of the abstract located adjacent to the title

    Epistemic freedom and education

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    First of all, I define the concept of epistemic freedom in the light of the changing nature of educational practice that prioritise over-prescriptive conceptions of learning. I defend the ‘reality’ of this freedom against possible determinist-related criticisms. I do this by stressing the concept of agency as characterised by ‘becoming’. I also discuss briefly some of the technical literature on the subject. I then move on to discuss Gramsci’s concept of hegemony and Foucault’s idea of ‘productive power’: I argue for the need of a counter-narrative of freedom that takes the form of a genealogy. Finally I discuss in more detail the nature of epistemic freedom and briefly discuss the ethical implications of the concept

    “Not Tied Up Neatly with a Bow”: Professionals’ Challenging Cases in Informed Consent for Genomic Sequencing

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    As the use of genomic technology has expanded in research and clinical settings, issues surrounding informed consent for genome and exome sequencing have surfaced. Despite the importance of informed consent, little is known about the specific challenges that professionals encounter when consenting patients or research participants for genomic sequencing. We interviewed 29 genetic counselors and research coordinators with considerable experience obtaining informed consent for genomic sequencing to understand their experiences and perspectives. As part of this interview, 24 interviewees discussed an informed consent case they found particularly memorable or challenging. We analyzed these case examples to determine the primary issue or challenge represented by each case. Challenges fell into two domains: participant understanding, and facilitating decisions about testing or research participation. Challenges related to participant understanding included varying levels of general and genomic literacy, difficulty managing participant expectations, and contextual factors that impeded participant understanding. Challenges related to facilitating decision-making included complicated family dynamics such as disagreement or coercion, situations in which it was unclear whether sequencing research would be a good use of participant time or resources, and situations in which the professional experienced disagreement or discomfort with participant decisions. The issues highlighted in these case examples are instructive in preparing genetics professionals to obtain informed consent for genomic sequencing

    X-Ray Evidence for Flare Density Variations and Continual Chromospheric Evaporation in Proxima Centauri

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    Using the XMM-Newton X-ray observatory to monitor the nearest star to the Sun, Proxima Centauri, we recorded the weakest X-ray flares on a magnetically active star ever observed. Correlated X-ray and optical variability provide strong support for coronal energy and mass supply by a nearly continuous sequence of rapid explosive energy releases. Variable emission line fluxes were observed in the He-like triplets of OVII and NeIX during a giant flare. They give direct X-ray evidence for density variations, implying densities between 2x10^{10} - 4x10^{11} cm^{-3} and providing estimates of the mass and the volume of the line-emitting plasma. We discuss the data in the context of the chromospheric evaporation scenario.Comment: 10 pages, 2 figures, accepted by The Astrophysical Journal, Letters; improved calculations of radiative loss of cool plasma (toward end of paper
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