Persistent current formation in a high-temperature Bose-Einstein condensate: an experimental test for c-field theory

Experimental stirring of a toroidally trapped Bose-Einstein condensate at high temperature generates a disordered array of quantum vortices that decays via thermal dissipation to form a macroscopic persistent current [T. W. Neely em et al. arXiv:1204.1102 (2012)]. We perform 3D numerical simulations of the experimental sequence within the Stochastic Projected Gross-Pitaevskii equation using ab initio determined reservoir parameters. We find that both damping and noise are essential for describing the dynamics of the high-temperature Bose field. The theory gives a quantitative account of the formation of a persistent current, with no fitted parameters.Comment: v2: 7 pages, 3 figures, new experimental data and numerical simulation

Indexing Giving: Examining State-level Data about Itemized Charitable Deductions Using Known Determinants of Giving

Average itemized charitable deductions by state are widely used as a measure of giving yet grossly misstate “generosity.” Extending a model initially developed by Gittell and Tebaldi (2004), this work finds that when considering state-level measures of economic and social factors determinant of individual giving at the micro-level, six of the 20 states said to be most generous on the popular “generosity index” have average itemized contributions at least 5 percent LOWER than their predicted giving capacity. Nine states in the bottom 20 on the “generosity index” have average itemized giving at or above the predicted levels. Further analysis using household-level survey data from the Center on Philanthropy Panel Study (a part of the Panel Study of Income Dynamics conducted by the University of Michigan) reveals significant differences in total secular and total religious giving by households in different Census regions (analysis is not possible at the state level using this data set). The secular and religious differences in giving largely account for the differing total amounts reported. The paper concludes with an appeal that generosity be evaluated as a percentage of income donated combined with percentage of households that donate in a given region

Giving Following a Crisis: An Historical Analysis

While conventional wisdom in fundraising maintains that donors of all types give in response to need, analysis of contributions from 1939 to 1999, including years of 17 national crises ranging from war, natural disaster, political crisis, and terrorism, shows that economic variables are strongly associated with giving, whereas crisis is seldom a significant factor. Crisis seems to matter in bivariate (giving/crisis) analysis, but not after controlling for economic changes in multivariate analyses. Results are very robust to type of crisis, time period, sources of giving and specification of model

ESTIMATING CORPORATE CHARITABLE GIVING for Giving USA

Estimating corporate giving is an important part of the estimation process for Giving USA and is used independently by a variety of practitioners, policy makers, business leaders, and the media. While Giving USA has changed its estimation process over time, it has never previously examined what might be the “best” model for these estimations. We tested hundreds of permutations and combinations of variables and specifications that were used historically and that were suggested to us by scholars and practitioners from around the country. This paper summarizes the problem, the process and the results

Looking and Thinking: How individuals with Williams syndrome make judgements about mental states

Individuals with the neuro-developmental disorder Williams syndrome (WS) are characterised by a combination of features which makes this group vulnerable socially, including mild-moderate cognitive difficulties, pro-social drive, and indiscriminate trust. The purpose of this study was to explore a key socio-communicative skill in individuals with WS, namely, mental state recognition abilities. We explored this skill in a detailed way by looking at how well individuals with WS recognise complex everyday mental states, and how they allocate their attention while making these judgements. Participants with WS were matched to two typically developing groups for comparison purposes, a verbal ability matched group and a chronological age matched group. While eye movements were recorded, participants were shown displays of eight different mental states in static and dynamic form, and they performed a forced-choice judgement on the mental state. Mental states were easier to recognise in dynamic form rather than static form. Mental state recognition ability for individuals with WS was poorer than expected by their chronological age, and at the level expected by their verbal ability. However, the pattern of mental state recognition for participants with WS varied according to mental state, and we found some interesting links between ease/difficulty recognising some mental states (worried/do not trust) and the classic behavioural profile associated with WS (high anxiety/indiscriminate trust). Furthermore, eye tracking data revealed that participants with WS allocated their attention atypically, with less time spent attending the information from the face regions. This challenges the widely held understanding of WS being associated with prolonged face and eye gaze, and indicates that there is more heterogeneity within this disorder in terms of socio-perception than previous reports would suggest

A Methodological Comparison of Giving Surveys: Indiana as a Test Case

Every 4 years, the Center on Philanthropy at Indiana University conducts a telephone survey (called Indiana Gives) of the giving and volunteering behaviors of Indiana citizens. In preparing to conduct Indiana Gives for 2000, a larger methodological question was asked: How much does survey methodology matter in generating accurate measures of giving and volunteering? In this most recent wave of the Indiana survey, conducted in October and November 2000, eight groups of approximately 100 randomly selected Indiana residents were asked to complete one of eight surveys related to giving and volunteering. It was found that the longer the module and the more detailed its prompts, the more likely a household was to recall making any charitable contribution and the higher the average level of its giving. These differences persisted even after controlling for differences in age, educational attainment, income, household status, race, and gender.ARNOV

Influence of transient pressure changes on speech intelligibility: Implications for nextgeneration train travel

High-speed trains are operated in increasingly complex railway networks and continual improvement of driver assistance systems is necessary to maintain safety. Speech offers the opportunity to provide information to the driver without disrupting visual attention. However, it is not known whether the transient pressure changes inside trains passing through tunnels interfere with speech intelligibility. Our primary goal was to test whether the most severe pressure variations occurring in high-speed trains (25 hPa in 2 s) affect speech intelligibility in individuals with normal hearing ability and secondly whether a potential effect would depend on the direction of the pressure change. A cross-over design was used to compare speech intelligibility, measured with the monosyllable word test by Wallenberg and Kollmeier, in steady ambient pressure versus subsequent to pressure events, both realised in a pressure chamber. Since data for a power calculation did not exist, we conducted a pilot study with 20 participants to estimate variance of intra-individual differences. The upper 80% confidence limit guided sample size of the main campaign, which was performed with 72 participants to identify a 10% difference while limiting alpha (5%) and beta error (10%). On average, a participant understood 0.7 fewer words following a pressure change event compared to listening in steady ambient pressure. However, this intra-individual differences varied strongly between participants, standard deviation (SD) +/- 4.5 words, resulting in a negligible effect size of 0.1 and the Wilcoxon signed rank test (Z = -1.26; p = 0.21) did not distinguish it from chance. When comparing decreasing and increasing pressure events an average of 0.2 fewer words were understood (+/- 3.9 SD). The most severe pressure changes expected to occur in high-speed trains passing through tunnels do not interfere with speech intelligibility and are in itself not a risk factor for loss of verbal information transmission

lHuman cytotoxic T lymphocytes with reduced sensitivity to Fas-induced apoptosis

Effector-memory T cells expressing Fas (Apo-1/CD95) are switched to an apoptotic program by cross-linking with Fas-ligand (FasL). Consequently, tumors that express FasL can induce apoptosis of infiltrating Fas-positive T lymphocytes and subdue any antitumor host immune response. Since Epstein-Barr virus (EBV)-associated tumors such as Hodgkin lymphoma (HL) and nasopharyngeal carcinoma (NPC) express FasL, we determined whether EBV-specific cytotoxic T lymphocytes (EBV-CTLs) could be modified to resist this evasion strategy. We show that long-term down-modulation of Fas can be achieved in EBV-CTLs by transduction with small interfering RNA (siRNA) encoded in a retrovirus. Modified T cells resisted Fas/FasL-mediated apoptosis compared with control cells and showed minimal cleavage of the caspase3 substrate poly(ADP-ribose) polymerase (PARP) protein after Fas engagement. Prolonged Fas stimulation selected a uniformly Fas(low) and FasL resistant population. Removal of responsiveness to this single death signal had no other discernible effects on EBV-CTLs. In particular, it did not lead to their autonomous growth since the modified EBV-CTLs remained polyclonal, and their survival and proliferation retained dependence on antigen-specific stimulation and on the presence of other physiologic growth signals. EBV-CTLs with knocked down Fas should have a selective functional and survival advantage over unmodified EBV-CTLs in the presence of tumors expressing FasL and may be of value for adoptive cellular therapy. (c) 2005 by The American Society of Hematology

Spherical Harmonics for the 1D Radiative Transfer Equation I: Reflected Light

A significant challenge in radiative transfer theory for atmospheres of exoplanets and brown dwarfs is the derivation of computationally efficient methods that have adequate fidelity to more precise, numerically demanding solutions. In this work, we extend the capability of the first open-source radiative transfer model for computing the reflected light of exoplanets at any phase geometry, PICASO: Planetary Intensity Code for Atmospheric Spectroscopy Observations. Until now, PICASO has implemented two-stream approaches to the solving the radiative transfer equation for reflected light, in particular following the derivations of Toon et al. (1989) (Toon89). In order to improve the model accuracy, we have considered higher-order approximations of the phase functions, namely, we have increased the order of approximation from 2 to 4, using spherical harmonics. The spherical harmonics approximation decouples spatial and directional dependencies by expanding the intensity and phase function into a series of spherical harmonics, or Legendre polynomials, allowing for analytical solutions for low-order approximations to optimize computational efficiency. We rigorously derive the spherical harmonics method for reflected light and benchmark the 4-term method (SH4) against Toon89 and two independent and higher-fidelity methods (CDISORT & doubling-method). On average, the SH4 method provides an order of magnitude increase in accuracy, compared to Toon89. Lastly, we implement SH4 within PICASO and observe only modest increase in computational time, compared to two-stream methods (20% increase).Comment: Accepted ApJ; 27 pages; 5 figures; Code available at https://github.com/natashabatalha/picaso; Zenodo release at https://zenodo.org/record/7765171#.ZC3G7uzMI8Y; Tutorials/figure reproducibility at https://natashabatalha.github.io/picaso/notebooks/10b_AnalyzingApproximationsReflectedLightSH.htm

Spherical Harmonics for the 1D Radiative Transfer Equation II: Thermal Emission

Approximate methods to estimate solutions to the radiative transfer equation are essential for the understanding of atmospheres of exoplanets and brown dwarfs. The simplest and most popular choice is the "two-stream method" which is often used to produce simple yet effective models for radiative transfer in scattering and absorbing media. Toon et al. (1989) (Toon89) outlined a two-stream method for computing reflected light and thermal spectra and was later implemented in the open-source radiative transfer model PICASO. In Part~I of this series, we developed an analytical spherical harmonics method for solving the radiative transfer equation for reflected solar radiation (Rooney et al. 2023), which was implemented in PICASO to increase the accuracy of the code by offering a higher-order approximation. This work is an extension of this spherical harmonics derivation to study thermal emission spectroscopy. We highlight the model differences in the approach for thermal emission and benchmark the 4-term method (SH4) against Toon89 and a high-stream discrete-ordinates method, CDISORT. By comparing the spectra produced by each model we demonstrate that the SH4 method provides a significant increase in accuracy, compared to Toon89, which can be attributed to the increased order of approximation and to the choice of phase function. We also explore the trade-off between computational time and model accuracy. We find that our 4-term method is twice as slow as our 2-term method, but is up to five times more accurate, when compared with CDISORT. Therefore, SH4 provides excellent improvement in model accuracy with minimal sacrifice in numerical expense.Comment: Submitted ApJ; 17 pages; 7 figures; Code available at https://github.com/natashabatalha/picaso; Zenodo release at https://zenodo.org/record/7765171#.ZC3G7uzMI8Y; Tutorials/figure reproducibility at https://natashabatalha.github.io/picaso/notebooks/10c_AnalyzingApproximationsThermal.html