2,271 research outputs found

    Nitrate uptake across biomes and the influence of elemental stoichiometry: A new look at LINX II

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    Considering recent increases in anthropogenic N loading, it is essential to identify the controls on N removal and retention in aquatic ecosystems because the fate of N has consequences for water quality in streams and downstream ecosystems. Biological uptake of nitrate (NO3−) is a major pathway by which N is removed from these ecosystems. Here we used data from the second Lotic Intersite Nitrogen eXperiment (LINX II) in a multivariate analysis to identify the primary drivers of variation in NO3− uptake velocity among biomes. Across 69 study watersheds in North America, dissolved organic carbon:NO3− ratios and photosynthetically active radiation were identified as the two most important predictor variables in explaining NO3− uptake velocity. However, within a specific biome the predictor variables of NO3− uptake velocity varied and included various physical, chemical, and biological attributes. Our analysis demonstrates the broad control of elemental stoichiometry on NO3− uptake velocity as well as the importance of biome-specific predictors. Understanding this spatial variation has important implications for biome-specific watershed management and the downstream export of NO3−, as well as for development of spatially explicit global models that describe N dynamics in streams and rivers

    Urgent Cares Outpace Health Policy In The U.S.

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    More and more medical practices across the country are rebranding themselves as urgent care centers to meet the growing demand for fast, affordable health care. In many states, they are regulated like physicians groups. However, there is a debate brewing among health care policy experts and government officials over whether these centers should have their own regulations. Such oversight could help patients expecting acute care avoid confusion to such a degree that they receive poor treatment from professionals who aren’t prepared to offer emergency services, or delayed treatment because they are bounced around from facility to facility

    Connecticut’s Liberal Image Hides a History of Systematic Housing Inequality, It’s Time For A Change

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    Affordable housing is an issue that plagues 10’s of millions of Americans in the United States. In Connecticut, decades of predatory zoning laws that differ from city to city and a broken public housing system has created a state with concentrated pockets of wealth and poverty that disproportionately affects people of color. Connecticut has an opportunity to change its decidedly unliberal policies by taking notes from Japan’s Zoning laws, that enable mixed-income families to live side by side, and activists like Connecticut’s very own Ned Coll, who fought for free and open beaches in the state in the \u2760\u27s and \u2770s. https://ash-rodriguez.medium.com/connecticuts-liberal-image-hides-a-history-of-systematic-housing-inequality-it-s-time-for-a-c2640e3dee5

    The Luminous Convolution Model as an alternative to dark matter in spiral galaxies

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    The Luminous Convolution Model (LCM) demonstrates that it is possible to predict the rotation curves of spiral galaxies directly from estimates of the luminous matter. We consider two frame-dependent effects on the light observed from other galaxies: relative velocity and relative curvature. With one free parameter, we predict the rotation curves of twenty-three (23) galaxies represented in forty-two (42) data sets. Relative curvature effects rely upon knowledge of both the gravitational potential from luminous mass of the emitting galaxy and the receiving galaxy, and so each emitter galaxy is compared to four (4) different Milky Way luminous mass models. On average in this sample, the LCM is more successful than either dark matter or modified gravity models in fitting the observed rotation curve data. Implications of LCM constraints on populations synthesis modeling are discussed in this paper. This paper substantially expands the results in arXiv:1309.7370.Comment: Implications of LCM constraints on populations synthesis modeling are discussed in this paper. This paper substantially expands the results in arxiv:1309.737

    Overcoming the Barriers to Successful Completion of GED Programs among Prison and Jail Inmates

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    This study examines the barriers faced by inmates participating in General Educational Development (GED) courses in prisons and jails, with the goal of proposing strategies for the removal of these barriers. By examining the literature surrounding prison and jail GED programs, the factors are categorized as those unique to each inmate (inmate factors), those experienced within the prison environment (environmental factors), and barriers that arise as a result of social conditions (outside factors). By examining various similar examples in the literature, solutions are discussed that have helped prison inmates overcome similar barriers

    Precise Measures of Orbital Period, Before and After Nova Eruption for QZ Aurigae

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    For the ordinary classical nova QZ Aurigae (which erupted in 1964), we report 1317 magnitudes from 1912--2016, including four eclipses detected on archival photographic plates from long before the eruption. We have accurate and robust measures of the orbital period both pre-eruption and post-eruption, and we find that the orbital period decreased, with a fractional change of -290.71+-0.28 parts-per-million across the eruption, with the orbit necessarily getting smaller. Further, we find that the light curve outside of eclipses and eruption is flat at near B=17.14 from 1912--1981, whereupon the average light curve starts fading down to B=17.49 with large variability. QZ Aur is a robust counter-example against the Hibernation model for the evolution of cataclysmic variables, where the model requires that all novae have their period increase across eruptions. Large period decreases across eruptions can easily arise from mass imbalances in the ejecta, as are commonly seen in asymmetric nova shells.Comment: MNRAS in press, 24 pages, 5 tables, 6 figure

    Memantine Improves Attentional Processes in Fragile X-Associated Tremor/Ataxia Syndrome: Electrophysiological Evidence from a Randomized Controlled Trial.

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    Progressive cognitive deficits are common in patients with fragile X-associated tremor/ataxia syndrome (FXTAS), with no targeted treatment yet established. In this substudy of the first randomized controlled trial for FXTAS, we examined the effects of NMDA antagonist memantine on attention and working memory. Data were analyzed for patients (24 in each arm) who completed both the primary memantine trial and two EEG recordings (at baseline and follow-up) using an auditory "oddball" task. Results demonstrated significantly improved attention/working memory performance after one year only for the memantine group. The event-related potential P2 amplitude elicited by non-targets was significantly enhanced in the treated group, indicating memantine-associated improvement in attentional processes at the stimulus identification/discrimination level. P2 amplitude increase was positively correlated with improvement on the behavioral measure of attention/working memory during target detection. Analysis also revealed that memantine treatment normalized the P2 habituation effect at the follow-up visit. These findings indicate that memantine may benefit attentional processes that represent fundamental components of executive function/dysfunction, thought to comprise the core cognitive deficit in FXTAS. The results provide evidence of target engagement of memantine, as well as therapeutically relevant information that could further the development of specific cognitive or disease-modifying therapies for FXTAS

    Efficiency of hydrophobic phosphonium ionic liquids and DMSO as recyclable cellulose dissolution and regeneration media

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    Hydrophobic, long-chain tetraalkylphosphonium acetate salts (ionic liquids) were combined with a dipolar aprotic co-solvent, dimethylsulfoxide (DMSO), and the feasibility of these solvent systems for cellulose dissolution and regeneration was studied. A 60 : 40 w/w mixture of the ionic liquid tetraoctylphosphonium acetate ([P-8888][OAc]) and DMSO was found to dissolve up to 8 wt% cellulose, whilst trioctyl(tetradecyl) phosphonium acetate ([P-14888][OAc]) dissolved up to 3 wt% cellulose. Water (an anti-solvent for cellulose) was found to give rise to biphasic liquid-liquid systems when combined with these mixtures, yielding an upper phase rich in ionic liquid and a lower aqueous phase. The liquid-liquid equilibria of the ternary systems were experimentally determined, finding that DMSO strongly partitioned towards the aqueous phase. Thus, a process scheme involving simultaneous regeneration of cellulose and recycling of the solvent system was envisioned, and demonstrated on a large scale using [P-8888] [OAc]. A large portion of the ionic liquid (ca. 60 wt%) was directly recovered via phase separation, with a further 37 wt% being recovered from the swollen cellulose phase and residual materials, bringing recovery to 97%. XRD analysis of the recovered cellulose materials showed a loss of crystallinity and conversion from Cellulose I to Cellulose II. Non-dissolving compositions of ionic liquid and DMSO did not affect cellulose crystallinity after cellulose pulp treatment.Peer reviewe

    Making it RAIN: Using Remotely Accessible Instruments in Nanotechnology to Enhance High School Science Courses

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    The Remotely Accessible Instruments in Nanotechnology (RAIN) Network is a conglomerate of nineteen community colleges, four-year universities and high school sites that aims to enhance STEM learning by bringing advanced technologies to K-12 education. RAIN provides free remote access to instruments such as Scanning Electron, Atomic Force and Transmission Electron Microscopes, as well as Energy Dispersive and Infrared Spectroscopy. The following is a variety of experiments and an empirical formula lab that can be performed in a high school physical science or chemistry classroom that utilizes the RAIN Network
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