3,479 research outputs found

    Comparison of fixation disparity measurement technique utilizing physiological diplopia quantified by the laser disparometer and the Sheedy disparometer

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    This study explored a new technique for measuring fixation disparity. The concept quantified superimposition of physiologically diplopic images to determine alignment of the subjects\u27 visual axis and fixation disparity. Fifteen subjects were tested using the new Laser Disparometer and the Sheedy Disparometer. Results showed a 0.88 correlation between the two methods and no significant difference between mean fixation disparity measurements. Future studies are needed with larger sample size to increase statistical support for the Laser Disparometer

    The life and health challenges of young Malaysian couples: results from a stakeholder consensus and engagement study to support non-communicable disease prevention

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    BACKGROUND: Malaysia faces burgeoning obesity and diabetes epidemics with a 250% and 88% increase respectively between 1996 and 2006. Identifying the health challenges of young adults in Malaysia, who constitute 27.5 % of the population, is critical for NCD prevention. The aim of the study was two-fold: (1) to achieve consensus amongst stakeholders on the most important challenge impacting the health of young adults, and (2) to engage with stakeholders to formulate a NCD prevention framework.METHODS: The Delphi Technique was utilised to achieve group consensus around the most important life and health challenges that young adults face in Malaysia. Subsequently, the results of the consensus component were shared with the stakeholders in an engagement workshop to obtain input on a NCD prevention framework.RESULTS: We found that life stress was a significant concern. It would seem that the apathy towards pursuing or maintaining a healthy lifestyle among young adults may be significantly influenced by the broader distal determinant of life stress. The high cost of living is suggested to be the main push factor for young working adults towards attaining better financial security to improve their livelihood. In turn, this leads to a more stressful lifestyle with less time to focus on healthier lifestyle choices.CONCLUSIONS: The findings highlight a pivotal barrier to healthier lifestyles. By assisting young adults to cope with daily living coupled with realistic opportunities to make healthier dietary choices, be more active, and less sedentary could assist in the development of NCD health promotion strategies<br/

    Quenching Spin Decoherence in Diamond through Spin Bath Polarization

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    We experimentally demonstrate that the decoherence of a spin by a spin bath can be completely eliminated by fully polarizing the spin bath. We use electron paramagnetic resonance at 240 gigahertz and 8 Tesla to study the spin coherence time T2T_2 of nitrogen-vacancy centers and nitrogen impurities in diamond from room temperature down to 1.3 K. A sharp increase of T2T_2 is observed below the Zeeman energy (11.5 K). The data are well described by a suppression of the flip-flop induced spin bath fluctuations due to thermal spin polarization. T2T_2 saturates at 250μs\sim 250 \mu s below 2 K, where the spin bath polarization is 99.4 %.Comment: 5 pages and 3 figure

    Dynamic Evolution of Antimicrobial Peptides Underscores Trade-Offs Between Immunity and Ecological Fitness

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    This work is licensed under a Creative Commons Attribution 4.0 International License.There is a developing interest in how immune genes may function in other physiological roles, and how traditionally non-immune peptides may, in fact, be active in immune contexts. In the absence of infection, the induction of the immune response is costly, and there are well-characterized trade-offs between immune defense and fitness. The agents behind these fitness costs are less understood. Here we implicate antimicrobial peptides (AMPs) as particularly costly effectors of immunity using an evolutionary framework. We describe the independent loss of AMPs in multiple lineages of Diptera (true flies), tying these observations back to life history. We then focus on the intriguing case of the glycine-rich AMP, Diptericin, and find several instances of loss, pseudogenization, and segregating null alleles. We suggest that Diptericin may be a particularly toxic component of the Dipteran immune response lost in flies either with reduced pathogen pressure or other environmental factors. As Diptericins have recently been described to have neurological roles, these findings parallel a developing interest in AMPs as potentially harmful neuropeptides, and AMPs in other roles beyond immunity

    Mass Dependent Loss of Resolution in Radially Inhomogeneous ExB Ion Traps

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    ExB ion traps, such as Fourier transform Ion Cyclotron Resonance mass spectrometers (FY:ICR), mass analyze sample ions based on differences in their cyclotron frequencies in a homogeneous magnetic field. The high resolution mass measurements of FT-ICR are based on the relationship between the frequency of the cyclotron orbit and the mass-to-charge (m/q) ratio of an ion. Both the orbit and the frequency/mass relationship result from the radial forces on the ion. Ions trapped by inhomogeneous electric fields experience different magnitudes of the radial electric fields at different positions resulting in a positionally dependent frequency. Such differences in orbital frequencies for ions of a single m/q ratio result in line broadening and loss of resolution

    The strain on scientific publishing

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    5 figures, 2 tables, 15 pages + references. Full-res figures at https://doi.org/10.6084/m9.figshare.24203790.v1Scientists are increasingly overwhelmed by the volume of articles being published. Total articles indexed in Scopus and Web of Science have grown exponentially in recent years; in 2022 the article total was 47% higher than in 2016, which has outpaced the limited growth, if any, in the number of practising scientists. Thus, publication workload per scientist (writing, reviewing, editing) has increased dramatically. We define this problem as the strain on scientific publishing. To analyse this strain, we present five data-driven metrics showing publisher growth, processing times, and citation behaviours. We draw these data from web scrapes, requests for data from publishers, and material that is freely available through publisher websites. Our findings are based on millions of papers produced by leading academic publishers. We find specific groups have disproportionately grown in their articles published per year, contributing to this strain. Some publishers enabled this growth by adopting a strategy of hostingspecial issues, which publish articles with reduced turnaround times. Given pressures on researchers to publish or perish to be competitive for funding applications, this strain was likely amplified by these offers to publish more articles. We also observed widespread year-over-year inflation of journal impact factors coinciding with this strain, which risks confusing quality signals. Such exponential growth cannot be sustained. The metrics we define here should enable this evolving conversation to reach actionable solutions to address the strain on scientific publishing

    The Compositional Nature of Verb and Argument Representations in the Human Brain

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    How does the human brain represent simple compositions of objects, actors,and actions? We had subjects view action sequence videos during neuroimaging (fMRI) sessions and identified lexical descriptions of those videos by decoding (SVM) the brain representations based only on their fMRI activation patterns. As a precursor to this result, we had demonstrated that we could reliably and with high probability decode action labels corresponding to one of six action videos (dig, walk, etc.), again while subjects viewed the action sequence during scanning (fMRI). This result was replicated at two different brain imaging sites with common protocols but different subjects, showing common brain areas, including areas known for episodic memory (PHG, MTL, high level visual pathways, etc.,i.e. the 'what' and 'where' systems, and TPJ, i.e. 'theory of mind'). Given these results, we were also able to successfully show a key aspect of language compositionality based on simultaneous decoding of object class and actor identity. Finally, combining these novel steps in 'brain reading' allowed us to accurately estimate brain representations supporting compositional decoding of a complex event composed of an actor, a verb, a direction, and an object.Comment: 11 pages, 6 figure

    Provenance and Paleogeography of the 25-17 Ma Rainbow Gardens Formation: Evidence for Tectonic Activity at Ca. 19 Ma and Internal Drainage rather than Throughgoing Paleorivers on the Southwestern Colorado Plateau

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    The paleogeographic evolution of the Lake Mead region of southern Nevada and northwest Arizona is crucial to understanding the geologic history of the U.S. Southwest, including the evolution of the Colorado Plateau and formation of the Grand Canyon. The ca. 25–17 Ma Rainbow Gardens Formation in the Lake Mead region, the informally named, roughly coeval Jean Conglomerate, and the ca. 24–19 Ma Buck and Doe Conglomerate southeast of Lake Mead hold the only stratigraphic evidence for the Cenozoic pre-extensional geology and paleogeography of this area. Building on prior work, we present new sedimentologic and stratigraphic data, including sandstone provenance and detrital zircon data, to create a more detailed paleogeographic picture of the Lake Mead, Grand Wash Trough, and Hualapai Plateau region from 25 to 18 Ma. These data confirm that sediment was sourced primarily from Paleozoic strata exposed in surrounding Sevier and Laramide uplifts and active volcanic fields to the north. In addition, a distinctive signal of coarse sediment derived from Proterozoic crystalline basement first appeared in the southwestern corner of the basin ca. 25 Ma at the beginning of Rainbow Gardens Formation deposition and then prograded north and east ca. 19 Ma across the southern half of the basin. Regional thermochronologic data suggest that Cretaceous deposits likely blanketed the Lake Mead region by the end of Sevier thrusting. Post-Laramide northward cliff retreat off the Kingman/Mogollon uplifts left a stepped erosion surface with progressively younger strata preserved northward, on which Rainbow Gardens Formation strata were deposited. Deposition of the Rainbow Gardens Formation in general and the 19 Ma progradational pulse in particular may reflect tectonic uplift events just prior to onset of rapid extension at 17 Ma, as supported by both thermochronology and sedimentary data. Data presented here negate the California and Arizona River hypotheses for an “old” Grand Canyon and also negate models wherein the Rainbow Gardens Formation was the depocenter for a 25–18 Ma Little Colorado paleoriver flowing west through East Kaibab paleocanyons. Instead, provenance and paleocurrent data suggest local to regional sources for deposition of the Rainbow Gardens Formation atop a stripped low-relief western Colorado Plateau surface and preclude any significant input from a regional throughgoing paleoriver entering the basin from the east or northeast
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