1,556 research outputs found

    Spatial dimensions of water quality value in New England river networks

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    Households’ willingness to pay (WTP) for water quality improvements—representing their economic value—depends on where improvements occur. Households often hold higher values for improvements close to their homes or iconic areas. Are there other areas where improvements might hold high value to individual households, do effects on WTP vary by type of improvement, and can these areas be identified even if they are not anticipated by researchers? To answer these questions, we integrated a water quality model and map-based, interactive choice experiment to estimate households’ WTP for water quality improvements throughout a river network covering six New England states. The choice experiment was implemented using a push-to-web survey over a sample of New England households. Voting scenarios used to elicit WTP included interactive geographic information system (GIS) maps that illustrated three water quality measures at various zoom levels across the study domain. We captured data on how respondents maneuvered through these maps prior to answering the value-eliciting questions. Results show that WTP was influenced by regionwide quality improvements and improvements surrounding each respondent’s home, as anticipated, but also by improvements in individualized locations identifiable via each respondent’s map interactions. These spatial WTP variations only appear for low-quality rivers and are focused around particular areas of New England. The study shows that dynamic map interactions can convey salient information for WTP estimation and that predicting spatial WTP heterogeneity based primarily on home or iconic locations, as typically done, may overlook areas where water quality has high value. Copyright © 2023 the Author(s)

    Cell type-specific binding patterns reveal that TCF7L2 can be tethered to the genome by association with GATA3

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    BACKGROUND: The TCF7L2 transcription factor is linked to a variety of human diseases, including type 2 diabetes and cancer. One mechanism by which TCF7L2 could influence expression of genes involved in diverse diseases is by binding to distinct regulatory regions in different tissues. To test this hypothesis, we performed ChIP-seq for TCF7L2 in six human cell lines. RESULTS: We identified 116,000 non-redundant TCF7L2 binding sites, with only 1,864 sites common to the six cell lines. Using ChIP-seq, we showed that many genomic regions that are marked by both H3K4me1 and H3K27Ac are also bound by TCF7L2, suggesting that TCF7L2 plays a critical role in enhancer activity. Bioinformatic analysis of the cell type-specific TCF7L2 binding sites revealed enrichment for multiple transcription factors, including HNF4alpha and FOXA2 motifs in HepG2 cells and the GATA3 motif in MCF7 cells. ChIP-seq analysis revealed that TCF7L2 co-localizes with HNF4alpha and FOXA2 in HepG2 cells and with GATA3 in MCF7 cells. Interestingly, in MCF7 cells the TCF7L2 motif is enriched in most TCF7L2 sites but is not enriched in the sites bound by both GATA3 and TCF7L2. This analysis suggested that GATA3 might tether TCF7L2 to the genome at these sites. To test this hypothesis, we depleted GATA3 in MCF7 cells and showed that TCF7L2 binding was lost at a subset of sites. RNA-seq analysis suggested that TCF7L2 represses transcription when tethered to the genome via GATA3. CONCLUSIONS: Our studies demonstrate a novel relationship between GATA3 and TCF7L2, and reveal important insights into TCF7L2-mediated gene regulation

    Quantum computation over continuous variables

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    This paper provides necessary and sufficient conditions for constructing a universal quantum computer over continuous variables. As an example, it is shown how a universal quantum computer for the amplitudes of the electromagnetic field might be constructed using simple linear devices such as beam-splitters and phase shifters, together with squeezers and nonlinear devices such as Kerr-effect fibers and atoms in optical cavities. Such a device could in principle perform `quantum floating point' computations. Problems of noise, finite precision, and error correction are discussed.Comment: 9 pages, Te

    Simulation of Many-Body Fermi Systems on a Universal Quantum Computer

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    We provide fast algorithms for simulating many body Fermi systems on a universal quantum computer. Both first and second quantized descriptions are considered, and the relative computational complexities are determined in each case. In order to accommodate fermions using a first quantized Hamiltonian, an efficient quantum algorithm for anti-symmetrization is given. Finally, a simulation of the Hubbard model is discussed in detail.Comment: Submitted 11/7/96 to Phys. Rev. Lett. 10 pages, 0 figure

    Electron spin resonance resolves intermediate triplet states in delayed fluorescence.

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    Molecular organic fluorophores are currently used in organic light-emitting diodes, though non-emissive triplet excitons generated in devices incorporating conventional fluorophores limit the efficiency. This limit can be overcome in materials that have intramolecular charge-transfer excitonic states and associated small singlet-triplet energy separations; triplets can then be converted to emissive singlet excitons resulting in efficient delayed fluorescence. However, the mechanistic details of the spin interconversion have not yet been fully resolved. We report transient electron spin resonance studies that allow direct probing of the spin conversion in a series of delayed fluorescence fluorophores with varying energy gaps between local excitation and charge-transfer triplet states. The observation of distinct triplet signals, unusual in transient electron spin resonance, suggests that multiple triplet states mediate the photophysics for efficient light emission in delayed fluorescence emitters. We reveal that as the energy separation between local excitation and charge-transfer triplet states decreases, spin interconversion changes from a direct, singlet-triplet mechanism to an indirect mechanism involving intermediate states

    Effects of Thyroxine Exposure on Osteogenesis in Mouse Calvarial Pre-Osteoblasts

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    The incidence of craniosynostosis is one in every 1,800-2500 births. The gene-environment model proposes that if a genetic predisposition is coupled with environmental exposures, the effects can be multiplicative resulting in severely abnormal phenotypes. At present, very little is known about the role of gene-environment interactions in modulating craniosynostosis phenotypes, but prior evidence suggests a role for endocrine factors. Here we provide a report of the effects of thyroid hormone exposure on murine calvaria cells. Murine derived calvaria cells were exposed to critical doses of pharmaceutical thyroxine and analyzed after 3 and 7 days of treatment. Endpoint assays were designed to determine the effects of the hormone exposure on markers of osteogenesis and included, proliferation assay, quantitative ALP activity assay, targeted qPCR for mRNA expression of Runx2, Alp, Ocn, and Twist1, genechip array for 28,853 targets, and targeted osteogenic microarray with qPCR confirmations. Exposure to thyroxine stimulated the cells to express ALP in a dose dependent manner. There were no patterns of difference observed for proliferation. Targeted RNA expression data confirmed expression increases for Alp and Ocn at 7 days in culture. The genechip array suggests substantive expression differences for 46 gene targets and the targeted osteogenesis microarray indicated 23 targets with substantive differences. 11 gene targets were chosen for qPCR confirmation because of their known association with bone or craniosynostosis (Col2a1, Dmp1, Fgf1, 2, Igf1, Mmp9, Phex, Tnf, Htra1, Por, and Dcn). We confirmed substantive increases in mRNA for Phex, FGF1, 2, Tnf, Dmp1, Htra1, Por, Igf1 and Mmp9, and substantive decreases for Dcn. It appears thyroid hormone may exert its effects through increasing osteogenesis. Targets isolated suggest a possible interaction for those gene products associated with calvarial suture growth and homeostasis as well as craniosynostosis. © 2013 Cray et al

    Confirmation of a pi_1^0 Exotic Meson in the \eta \pi^0 System

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    The exclusive reaction πpηπ0n\pi^- p \to \eta \pi^0 n, ηπ+ππ0\eta \to \pi^+ \pi^- \pi^0 at 18 GeV/c/c has been studied with a partial wave analysis on a sample of 23~492 ηπ0n\eta \pi^0 n events from BNL experiment E852. A mass-dependent fit is consistent with a resonant hypothesis for the P+P_+ wave, thus providing evidence for a neutral exotic meson with JPC=1+J^{PC} = 1^{-+}, a mass of 1257±20±251257 \pm 20 \pm 25 MeV/c2/c^2, and a width of 354±64±60354 \pm 64 \pm 60 MeV/c2/c^2. New interpretations of the meson exotics in neutral ηπ0\eta \pi^0 system observed in E852 and Crystal Barrel experiments are discussed.Comment: p3, rewording the paragraph (at the bottom) about the phase variations. p4, rewording paragrath "The second method ..." . p4, at the bottom of paragrath "The third method ..." added consistent with the results of methods 1 and 2

    Multimodal Functional Network Connectivity: An EEG-fMRI Fusion in Network Space

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    EEG and fMRI recordings measure the functional activity of multiple coherent networks distributed in the cerebral cortex. Identifying network interaction from the complementary neuroelectric and hemodynamic signals may help to explain the complex relationships between different brain regions. In this paper, multimodal functional network connectivity (mFNC) is proposed for the fusion of EEG and fMRI in network space. First, functional networks (FNs) are extracted using spatial independent component analysis (ICA) in each modality separately. Then the interactions among FNs in each modality are explored by Granger causality analysis (GCA). Finally, fMRI FNs are matched to EEG FNs in the spatial domain using network-based source imaging (NESOI). Investigations of both synthetic and real data demonstrate that mFNC has the potential to reveal the underlying neural networks of each modality separately and in their combination. With mFNC, comprehensive relationships among FNs might be unveiled for the deep exploration of neural activities and metabolic responses in a specific task or neurological state

    Cancer disparities in Southeast Asia: intersectionality and a call to action.

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    Southeast Asia has a population of over 680 million people—approximately half the population of India and twice the population of the United States—and is a region marked by rich and complex histories and cultures, dynamic growth, and unique and evolving health challenges.1 Despite the momentum of economic development, health inequalities persist. These inequities have been aggravated since the COVID-19 pandemic, which pushed millions further into poverty, possibly exacerbating health disparities, especially among populations who suffer vulnerabilities.2 Particularly salient are the challenges associated with providing adequate care for people with cancer, a leading cause of morbidity and mortality in the region.1,2 Cancer incidence and mortality in the region are projected to rise in the coming decades, given population growth and rapidly changing socioeconomic and geopolitical factors, as well as a host of interrelated and dynamic environmental, behavioral, and occupational risk factors.1, 2, 3 Large epidemiologic studies have demonstrated differences among Southeast Asian countries in terms of cancer incidence and mortality.3 Epidemiologic patterns can be attributed to variations in complex risk factors, access to screening and cancer care, and likely genetic predisposition.1, 2, 3 However, these differences also underscore that within each country exist richly diverse populations that experience disparities in cancer risk, screening, care access, outcomes, and survivorship in ways that require further examination. We draw attention to disparities in cancer in Southeast Asian countries. We highlight the need to study cancer disparities affecting minoritised groups in Southeast Asia—not only along lines of race/ethnicity, but also people minoritised along lines of sex/gender, socioeconomic status, religion, geography, and others. We highlight the intersectionality of elements of an individual's identity. Intersectionality, developed by critical race theorist Professor Kimberlé Crenshaw in 1989, is an analytic framework borne out of Black American feminist scholarship, that examines how a person's sociopolitical identities lead to disparate balances of privilege and discrimination.4 An intersectional approach would demonstrate that an individual or a community does not only experience economic poverty as the sole barrier to improved health; such an approach would examine how other identities such as religion or immigration status affect access to care. These different social determinants of health are not mutually exclusive; their interrelationships are complex, with consequences for health.5 We leverage the intersectional approach, which parallels the inherently syncretic cultures and histories of Southeast Asian nations, and explore how these identities impact access to cancer care. Meaningful cancer research focusing on peoples of Southeast Asia could present many opportunities for intervention and improvement
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