1,001 research outputs found

    Working with Grantees: The Keys to Success and Five Program Officers Who Exemplify Them

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    Successful foundation-grantee relationships hinge on the prowess of individual program officers, whose abilities may vary widely within a single foundation. This research explores what grantees value in their relationships with program officers and identifies four keys to success. Five high-performing program officers share their stories

    Genealogy Extraction and Tree Generation from Free Form Text

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    Genealogical records play a crucial role in helping people to discover their lineage and to understand where they come from. They provide a way for people to celebrate their heritage and to possibly reconnect with family they had never considered. However, genealogical records are hard to come by for ordinary people since their information is not always well established in known databases. There often is free form text that describes a person’s life, but this must be manually read in order to extract the relevant genealogical information. In addition, multiple texts may have to be read in order to create an extensive tree. This thesis proposes a novel three part system which can automatically interpret free form text to extract relationships and produce a family tree compliant with GED- COM formatting. The first subsystem builds an extendable database of genealogical records that are systematically extracted from free form text. This corpus provides the tagged data for the second subsystem, which trains a Naı̈ve Bayes classifier to predict relationships from free form text by examining the types of relationships for pairs of entities and their associated feature vectors. The last subsystem accumulates extracted relationships into family trees. When a multiclass Naı̈ve Bayes classifier is used, the proposed system achieves an accuracy of 54%. When binary Naı̈ve Bayes classifiers are used, the proposed system achieves accuracies of 69% for the child to parent relationship classifier, 75% for the spousal relationship classifier, and 73% for the sibling relationship classifier

    Family Moves and the Future of Public Education

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    State laws compel school-aged children to attend school while fully funding only public schools. Especially following the COVID-19 pandemic, this arrangement is under attack — from some for unconstitutionally coercing families to expose their children to non-neutral values to which they object and from others for ignoring the developmental needs of students, particularly students of color and in poverty whom public schools have long underserved. This Article argues that fully subsidized public education is constitutional as long as public schools fulfill their mission to model and commit people to liberal democratic values of tolerance and respect for all persons as equal choosers. To be sure, those values are not neutral. But as Brown v. Board famously concluded, their promotion in public schools is perhaps the nation’s and states’ single most compelling interest, because it is essential to the ability of people with diverse beliefs to live together harmoniously while preserving their vast freedoms in other respects. To keep public education from qualifying those freedoms any more than necessary, states give families a right to opt for private education, but at their own expense. This arrangement serves the compelling interest in public education, however, only if public schools — bolstered by compulsory education laws and their uniquely full public subsidization — attract enough families. For well over a century, public schools have attracted around 90% of all school children. Today, however, family moves away from public education are eroding its ability to attract children due principally to public education’s conflation of “public” with bureaucratically “uniform” education — precluding pedagogically, democratically, and equitably essential differentiation among students. The Article proposes ways public schools can better model liberal democratic values by engaging all families in the cooperative and differentiated direction of their children’s learning

    Pregnant smokers’ experiences and opinions of techniques aimed to address barriers and facilitators to smoking cessation: A qualitative study

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    Pregnant women experience certain barriers and facilitators (B&Fs) when trying to quit smoking. This study aimed to elicit women’s views on techniques that could help overcome or enhance these. Semi-structured interviews were conducted with 12 pregnant women who had experience of smoking during pregnancy. Participants were prompted to discuss experiences of B&Fs and give suggestions of techniques that could address these appropriately. A thematic analysis was conducted using the one sheet of paper method. Four themes relating to suggested techniques were identified: accessing professional help, nicotine replacement therapy (NRT), distraction, and social interactions. Experiences of accessing professional help were generally positive, especially if there was a good rapport with, and easy access to a practitioner. Most women were aware of NRT, those who had used it reported both negative and positive experiences. Praise and encouragement from others towards cessation attempts appeared motivating; peer support groups were deemed useful. Women reported experiencing B&Fs which fell under four themes: influence of others, internal motivation, cues to smoke, and health. Overall, accessing professional support generated positive changes in smoking habits. Establishing ways of how to encourage more women to seek help and raising awareness of different types of support available would seem beneficial

    Second-order group knockoffs with applications to GWAS

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    Conditional testing via the knockoff framework allows one to identify -- among large number of possible explanatory variables -- those that carry unique information about an outcome of interest, and also provides a false discovery rate guarantee on the selection. This approach is particularly well suited to the analysis of genome wide association studies (GWAS), which have the goal of identifying genetic variants which influence traits of medical relevance. While conditional testing can be both more powerful and precise than traditional GWAS analysis methods, its vanilla implementation encounters a difficulty common to all multivariate analysis methods: it is challenging to distinguish among multiple, highly correlated regressors. This impasse can be overcome by shifting the object of inference from single variables to groups of correlated variables. To achieve this, it is necessary to construct "group knockoffs." While successful examples are already documented in the literature, this paper substantially expands the set of algorithms and software for group knockoffs. We focus in particular on second-order knockoffs, for which we describe correlation matrix approximations that are appropriate for GWAS data and that result in considerable computational savings. We illustrate the effectiveness of the proposed methods with simulations and with the analysis of albuminuria data from the UK Biobank. The described algorithms are implemented in an open-source Julia package Knockoffs.jl, for which both R and Python wrappers are available.Comment: 46 pages, 10 figures, 2 tables, 3 algorithm

    Practical Schnorr Threshold Signatures Without the Algebraic Group Model

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    Threshold signatures are digital signature schemes in which a set of nn signers specify a threshold tt such that any subset of size tt is authorized to produce signatures on behalf of the group. There has recently been a renewed interest in this primitive, largely driven by the need to secure highly valuable signing keys, e.g., DNSSEC keys or keys protecting digital wallets in the cryptocurrency ecosystem. Of special interest is FROST, a practical Schnorr threshold signature scheme, which is currently undergoing standardization in the IETF and whose security was recently analyzed at CRYPTO\u2722. We continue this line of research by focusing on FROST\u27s unforgeability combined with a practical distributed key generation (DKG) algorithm. Existing proofs of this setup either use non-standard heuristics, idealized group models like the AGM, or idealized key generation. Moreover, existing proofs do not consider all practical relevant optimizations that have been proposed. We close this gap between theory and practice by presenting the Schnorr threshold signature scheme Olaf, which combines the most efficient known FROST variant FROST3 with a variant of Pedersen\u27s DKG protocol (as commonly used for FROST), and prove its unforgeability. Our proof relies on the AOMDL assumption (a weaker and falsifiable variant of the OMDL assumption) and, like proofs of regular Schnorr signatures, on the random oracle model

    Deterministic positioning of nanophotonic waveguides around single self-assembled quantum dots

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    The capability to embed self-assembled quantum dots (QDs) at predefined positions in nanophotonic structures is key to the development of complex quantum photonic architectures. Here, we demonstrate that QDs can be deterministically positioned in nanophotonic waveguides by pre-locating QDs relative to a global reference frame using micro-photoluminescence (Ό\muPL) spectroscopy. After nanofabrication, Ό\muPL images reveal misalignments between the central axis of the waveguide and the embedded QD of only (9±46(9\pm46) nm and (1±33(1\pm33) nm, for QDs embedded in undoped and doped membranes, respectively. A priori knowledge of the QD positions allows us to study the spectral changes introduced by nanofabrication. We record average spectral shifts ranging from 0.1 to 1.1 nm, indicating that the fabrication-induced shifts can generally be compensated by electrical or thermal tuning of the QDs. Finally, we quantify the effects of the nanofabrication on the polarizability, the permanent dipole moment and the emission frequency at vanishing electric field of different QD charge states, finding that these changes are constant down to QD-surface separations of only 70 nm. Consequently, our approach deterministically integrates QDs into nanophotonic waveguides whose light-fields contain nanoscale structure and whose group index varies at the nanometer level.Comment: 26 pages, 9 figures. Updated version of the manuscript, with new appendices and new figure

    GOES-R STATIONKEEPING AND MOMENTUM MANAGEMENT

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    The NOAA Geostationary Operational Environmental Satellites (GOES) fire thrusters to remain within a 1deg longitude-latitude box and to dump accumulated angular momentum. In the past, maneuvers have disrupted GOES imaging due to attitude transients and the loss of orbit knowledge. If the R-series of spacecraft to be launched starting in 2012 were to follow current practice, maneuvers would still fail to meet Image Navigation and Registration (INR) specifications during and after thruster firings. Although maneuvers and recovery take only one percent of spacecraft lifetime, they sometimes come at inopportune times, such as hurricane season, when coverage is critical. To alleviate this problem, thruster firings small enough not to affect imaging are being considered. Eliminating post-maneuver recovery periods increases availability and facilitates autonomous operation. Frequent maneuvers also reduce 1ongitudeAatitude variation and allow satellite co-location. Improved orbit observations come from a high-altitude GPS receiver, and improved attitude control comes from thruster torque compensation. This paper reviews the effects of thruster firings on position knowledge and pointing control and suggests that low-thrust burns plus GPS and feedforward control offer a less disruptive approach to GOES-R stationkeeping and momentum management

    Time-Efficient Black Blood RCA Wall Imaging at 3T Using Improved Motion Sensitized Driven Equilibrium (iMSDE): Feasibility and Reproducibility

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    The aim of this study was to explore the feasibility and reproducibility of a time-efficient coronary vessel wall measurement approach using an improved motion-sensitized driven equilibrium (iMSDE) pulse sequence.In this study, the iMSDE pulse sequence was first optimized and then applied on a group of healthy volunteers (N = 10) to evaluate its feasibility of vessel wall visualization. The same technique was also applied on a separate group of volunteers (N = 19) for a reproducibility study by scanning the same subject in two separate sessions. The iMSDE sequence was found to provide good coronary vessel wall delineation. It was also found to provide reproducible coronary vessel wall diameter and thickness measurements in both proximal and middle segments of the right coronary artery.The feasibility and reproducibility of iMSDE based coronary vessel wall imaging were demonstrated for the first time, paving the way for further testing in a clinical environment for fast and accurate coronary artery disease detection
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