95 research outputs found

    Performance variation in Leptasterias spp. among populations and habitats

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    Leptasterias spp. are six rayed sea stars that are found in rocky intertidal habitats ranging from the California coast to Alaska. In central California, Leptasterias spp. can be found in a variety of intertidal habitats in mixed populations. There are multiple clades that represent these populations and it is thought that they may vary behaviorally, including habitat preference. To investigate this individuals were collected from Pigeon Point, San Mateo, CA and characterized into two habitat categories according to where they were found: rocky habitat and pool habitat. To test for behavioral variation among habitats, righting response was used as a performance measure. Righting response time was measured in the field and was repeatedly measured in the lab under controlled conditions. It is hypothesized that individuals living in pool habitats are more mobile due to wave action and therefore will have a faster righting response. This study suggests that there may be significant performance differences among these habitat preferences and that this may also be reflected in the genetics. A methodology for further investigating these suggestions is offered here

    A Modified T-Mixer Simulation, Fabrication, and Characterization For 1D Diffusion Controlled Studies

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    Here, we describe a simple and unique architecture of a microfluidic mixer that can mix two streams (Water and Fluorescein Isothiocyanate (FITC) buffer) with 30% efficiency. The overall mixing in this design is dominated by 1D diffusion, and to enhance mixing, we used three different types of geometric obstacles inside the channel. Comsol multiphysics simulation software was used to validate the theoretical mixing efficiency (at Reynolds Number, Re ~ 0.1, 1, and 10) of this device. We utilized soft lithography and replica molding techniques to fabricate the device out of Polydimethylsiloxane (PDMS, a commonly used polymer) on a glass substrate. The effective length of our microfluidic mixer is 5mm, and the channel width is about 200 microns with 50 micron height. It is composed of three different shapes of obstacles (e.g., 6 cones, 3 arrays of rectangular bars, and 5 circular posts), and all of these are placed inside the main channel. FITC buffer (Diffusion co-efficient, D = 0.5 x 10-9 m2/s) and DI water were used to investigate the mixer performance at Re~1. Simulated and experimental results are based on approximately 1.1 mm2 flow area and suggest that 30% mixing is achievable with the current design

    Comparison of common lilac (Syringa vulgaris) phenology timing between historical data and current Project BudBurst citizen science data: challenges and lessons learned.

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    Observing the timing of plant phenology provides a way to monitor and predict effects of ecological change on plants. This study compared historical data for common lilac dating from 1956-2003 with recent lilac phenology data collected by Project BudBurst citizen scientists from 2007-2013. Due to the lack of accessible growing degree day data, it was not possible to directly examine climate effects on phenology timing. Instead, we compared geographic distribution patterns between historical and Project BudBurst data to explore what factors might contribute to the timing of phenophase dates between data sets. T-tests were performed on latitude, longitude, and day of year of observation (Julian date) for first flower and first leaf between the two data sets. Differences between latitude were not significant for first flower and first leaf (p = 0.789, p = 0.489, respectively) but there was a difference between longitude for both variables (p\u3c0.001). Mean observation dates for Project BudBurst were 9.5 days earlier for first flower (significantly different, p = 0.0001) and 2.3 days earlier for first leaf (no significant difference, p = 0.063) but the difference in longitude and the small sample size of the Project BudBurst data set makes these findings questionable. Because of the effect of longitude, we suggest future analyses of data by regions. Additional Project BudBurst observations in the western U.S. would allow better comparisons in that region and encouraging observations near historic sites would take advantage of a long, rich data set

    Development of the Continuous-Fill Brine Evaporation Bag (BEB) System

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    The existing water recovery system on the International Space Station (ISS) is limited to 70 percent reclamation; consequently, long duration space missions are currently unfeasible due to the large quantity of water necessary to sustain the crew. The Brine Evaporation Bag (BEB) is a proposed system to supplement the existing water recovery system aboard the ISS and future deep space missions that can increase water recovery to 99 percent. The BEB project previously focused on the development of only the bag portion of the system. This paper focuses on the development of the BEB Evaporator. It will discuss the work to understand, optimize, and improve the entire BEB system while implementing a continuous-fill process. The results of that development and the advantages and limitations of the continuous-fill process will be presented

    Reducing Decisional Conflict and Enhancing Satisfaction with Information among Women Considering Breast Reconstruction following Mastectomy: Results from the BRECONDA Randomized Controlled Trial

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    Background: Deciding whether or not to have breast reconstruction following breast cancer diagnosis is a complex decision process. This randomized controlled trial assessed the impact of an online decision aid [Breast RECONstruction Decision Aid (BRECONDA)] on breast reconstruction decision-making. Methods: Women (n = 222) diagnosed with breast cancer or ductal carcinoma in situ, and eligible for reconstruction following mastectomy, completed an online baseline questionnaire. They were then assigned randomly to receive either standard online information about breast reconstruction (control) or standard information plus access to BRECONDA (intervention). Participants then completed questionnaires at 1 and 6 months after randomization. The primary outcome was participants' decisional conflict 1 month after exposure to the intervention. Secondary outcomes included decisional conflict at 6 months, satisfaction with information at 1 and 6 months, and 6-month decisional regret. Results: Linear mixed-model analyses revealed that 1-month decisional conflict was significantly lower in the intervention group (27.18) compared with the control group (35.5). This difference was also sustained at the 6-month follow-up. Intervention participants reported greater satisfaction with information at 1- and 6-month follow-up, and there was a nonsignificant trend for lower decisional regret in the intervention group at 6-month follow-up. Intervention participants' ratings for BRECONDA demonstrated high user acceptability and overall satisfaction. Conclusions: Women who accessed BRECONDA benefited by experiencing significantly less decisional conflict and being more satisfied with information regarding the reconstruction decisional process than women receiving standard care alone. These findings support the efficacy of BRECONDA in helping women to arrive at their breast reconstruction decision

    Gold Nanoparticles Coated Optical Fiber for Real-time Localized Surface Plasmon Resonance Analysis of In-situ Light-Matter Interactions

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    In situ measurement of analytes for in vivo or in vitro systems has been challenging due to the bulky size of traditional analytical instruments. Also, frequent in vitro concentration measurements rely on fluorescence-based methods or direct slicing of the matrix for analyses. These traditional approaches become unreliable if localized and in situ analyses are needed. In contrast, for in situ and real-time analysis of target analytes, surface-engineered optical fibers can be leveraged as a powerful miniaturized tool, which has shown promise from bio to environmental studies. Herein, we demonstrate an optical fiber functionalized with gold nanoparticles using a dip-coating process to investigate the interaction of light with molecules at or near the surface of the optical fiber. Localized surface plasmon resonance from the light-matter interaction enables the detection of minute changes in the refractive index of the surrounding medium. We used this principle to assess the in situ molecular distribution of a synthetic drug (methylene blue) in an in vitro matrix (agarose gel) having varying concentrations. Leveraging the probed Z-height in diffused analytes, combined with its in silico data, our platform shows the feasibility of a simple optofluidic tool. Such straightforward in situ measurements of analytes with optical fiber hold potential for real-time molecular diffusion and molecular perturbation analyses relevant to biomedical and clinical studies

    Results of the FY15 Brine Evaporation Bag (BEB) Technology Down-Select Testing

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    The Brine Evaporation Bag (BEB) recently participated in the Brine Concentrator Technology (BCT) Technology Down-Select (TDS). It was found that the BEB System is able to process ISS (International Space Station) Alternate Pretreat Brine at a rate high enough for ISS application as well as future deep space missions. The BEB System is also capable of processing the brine to a solid residue which will add to the stability and safety of storing the brine residue. The results of the BEB testing for the BCT-TDS will be presented in this paper

    On the orbits that generate the X-shape in the Milky Way bulge

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    The Milky Way (MW) bulge shows a boxy/peanut or X-shaped bulge (hereafter BP/X) when viewed in infrared ormicrowave bands.We examine orbits in an N-body model of a barred disc galaxy that is scaled to match the kinematics of theMWbulge.We generate maps of projected stellar surface density, unsharp masked images, 3D excess-mass distributions (showing mass outside ellipsoids), line-of-sight number count distributions, and 2D line-of-sight kinematics for the simulation as well as co-added orbit families, in order to identify the orbits primarily responsible for the BP/X shape. We estimate that between 19 and 23 per cent of the mass of the bar in this model is associated with the BP/X shape and that the majority of bar orbits contribute to this shape that is clearly seen in projected surface density maps and 3D excess mass for non-resonant box orbits, 'banana' orbits, 'fish/pretzel' orbits and 'brezel' orbits. Although only the latter two families (comprising 7.5 per cent of the total mass) show a distinct X-shape in unsharp masked images, we find that nearly all bar orbit families contribute some mass to the 3D BP/X-shape. All co-added orbit families show a bifurcation in stellar number count distribution with distance that resembles the bifurcation observed in red clump stars in the MW. However, only the box orbit family shows an increasing separation of peaks with increasing galactic latitude |b|, similar to that observed. Our analysis suggests that no single orbit family fully explains all the observed features associated with the MW's BP/X-shaped bulge, but collectively the non-resonant boxes and various resonant boxlet orbits contribute at different distances from the centre to produce this feature. We propose that since box orbits (which are the dominant population in bars) have three incommensurable orbital fundamental frequencies, their 3D shapes are highly flexible and, like Lissajous figures, this family of orbits is most easily able to adapt to evolution in the shape of the underlying potential. © 2017 The Authors

    BAF complex maintains glioma stem cells in pediatric H3K27M glioma

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    Diffuse midline gliomas are uniformly fatal pediatric central nervous system cancers that are refractory to standard-of-care therapeutic modalities. The primary genetic drivers are a set of recurrent amino acid substitutions in genes encoding histone H3 (H3K27M), which are currently undruggable. These H3K27M oncohistones perturb normal chromatin architecture, resulting in an aberrant epigenetic landscape. To interrogate for epigenetic dependencies, we performed a CRISPR screen and show that patient-derived H3K27M-glioma neurospheres are dependent on core components of the mammalian BAF (SWI/SNF) chromatin remodeling complex. The BAF complex maintains glioma stem cells in a cycling, oligodendrocyte precursor cell–like state, in which genetic perturbation of the BAF catalytic subunit SMARCA4 (BRG1), as well as pharmacologic suppression, opposes proliferation, promotes progression of differentiation along the astrocytic lineage, and improves overall survival of patient-derived xenograft models. In summary, we demonstrate that therapeutic inhibition of the BAF complex has translational potential for children with H3K27M gliomas. Significance: Epigenetic dysregulation is at the core of H3K27M-glioma tumorigenesis. Here, we identify the BRG1–BAF complex as a critical regulator of enhancer and transcription factor landscapes, which maintain H3K27M glioma in their progenitor state, precluding glial differentiation, and establish pharmacologic targeting of the BAF complex as a novel treatment strategy for pediatric H3K27M glioma

    Measuring universal health coverage based on an index of effective coverage of health services in 204 countries and territories, 1990–2019 : A systematic analysis for the Global Burden of Disease Study 2019

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    Background Achieving universal health coverage (UHC) involves all people receiving the health services they need, of high quality, without experiencing financial hardship. Making progress towards UHC is a policy priority for both countries and global institutions, as highlighted by the agenda of the UN Sustainable Development Goals (SDGs) and WHO's Thirteenth General Programme of Work (GPW13). Measuring effective coverage at the health-system level is important for understanding whether health services are aligned with countries' health profiles and are of sufficient quality to produce health gains for populations of all ages. Methods Based on the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, we assessed UHC effective coverage for 204 countries and territories from 1990 to 2019. Drawing from a measurement framework developed through WHO's GPW13 consultation, we mapped 23 effective coverage indicators to a matrix representing health service types (eg, promotion, prevention, and treatment) and five population-age groups spanning from reproductive and newborn to older adults (≥65 years). Effective coverage indicators were based on intervention coverage or outcome-based measures such as mortality-to-incidence ratios to approximate access to quality care; outcome-based measures were transformed to values on a scale of 0–100 based on the 2·5th and 97·5th percentile of location-year values. We constructed the UHC effective coverage index by weighting each effective coverage indicator relative to its associated potential health gains, as measured by disability-adjusted life-years for each location-year and population-age group. For three tests of validity (content, known-groups, and convergent), UHC effective coverage index performance was generally better than that of other UHC service coverage indices from WHO (ie, the current metric for SDG indicator 3.8.1 on UHC service coverage), the World Bank, and GBD 2017. We quantified frontiers of UHC effective coverage performance on the basis of pooled health spending per capita, representing UHC effective coverage index levels achieved in 2019 relative to country-level government health spending, prepaid private expenditures, and development assistance for health. To assess current trajectories towards the GPW13 UHC billion target—1 billion more people benefiting from UHC by 2023—we estimated additional population equivalents with UHC effective coverage from 2018 to 2023. Findings Globally, performance on the UHC effective coverage index improved from 45·8 (95% uncertainty interval 44·2–47·5) in 1990 to 60·3 (58·7–61·9) in 2019, yet country-level UHC effective coverage in 2019 still spanned from 95 or higher in Japan and Iceland to lower than 25 in Somalia and the Central African Republic. Since 2010, sub-Saharan Africa showed accelerated gains on the UHC effective coverage index (at an average increase of 2·6% [1·9–3·3] per year up to 2019); by contrast, most other GBD super-regions had slowed rates of progress in 2010–2019 relative to 1990–2010. Many countries showed lagging performance on effective coverage indicators for non-communicable diseases relative to those for communicable diseases and maternal and child health, despite non-communicable diseases accounting for a greater proportion of potential health gains in 2019, suggesting that many health systems are not keeping pace with the rising non-communicable disease burden and associated population health needs. In 2019, the UHC effective coverage index was associated with pooled health spending per capita (r=0·79), although countries across the development spectrum had much lower UHC effective coverage than is potentially achievable relative to their health spending. Under maximum efficiency of translating health spending into UHC effective coverage performance, countries would need to reach 1398pooledhealthspendingpercapita(US1398 pooled health spending per capita (US adjusted for purchasing power parity) in order to achieve 80 on the UHC effective coverage index. From 2018 to 2023, an estimated 388·9 million (358·6–421·3) more population equivalents would have UHC effective coverage, falling well short of the GPW13 target of 1 billion more people benefiting from UHC during this time. Current projections point to an estimated 3·1 billion (3·0–3·2) population equivalents still lacking UHC effective coverage in 2023, with nearly a third (968·1 million [903·5–1040·3]) residing in south Asia. Interpretation The present study demonstrates the utility of measuring effective coverage and its role in supporting improved health outcomes for all people—the ultimate goal of UHC and its achievement. Global ambitions to accelerate progress on UHC service coverage are increasingly unlikely unless concerted action on non-communicable diseases occurs and countries can better translate health spending into improved performance. Focusing on effective coverage and accounting for the world's evolving health needs lays the groundwork for better understanding how close—or how far—all populations are in benefiting from UHC
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