Evidentiary Privileges and the Exclusion of Derivative Evidence: Commentary and Analysis

Invocation of an evidentiary privilege traditionally meant that the confidential communications of a holder were protected from disclosure during judicial, administrative, or legislative proceedings. This model of evidentiary privilege law does not take into account information gathered from unauthorized preproceeding disclosures of otherwise privileged communications. A minority of courts seem willing to exclude this derivative evidence with little or no explanation. These courts may unwittingly base their decision on privacy concepts recently proposed as one of the modern justifications for the existence of evidentiary privilege in law. Courts confronted with this issue analyze it in confusingly, and often contrastingly, different manners

Evidence For Temperature Change And Oblique Pulsation From Light Curve Fits Of The Pulsating White Dwarf GD 358

Convective driving, the mechanism originally proposed by Brickhill for pulsating white dwarf stars, has gained general acceptance as the generic linear instability mechanism in DAV and dbV white dwarfs. This physical mechanism naturally leads to a nonlinear formulation, reproducing the observed light curves of many pulsating white dwarfs. This numerical model can also provide information on the average depth of a star's convection zone and the inclination angle of its pulsation axis. In this paper, we give two sets of results of nonlinear light curve fits to data on the dbV GD 358. Our first fit is based on data gathered in 2006 by the Whole Earth Telescope; this data set was multiperiodic containing at least 12 individual modes. Our second fit utilizes data obtained in 1996, when GD 358 underwent a dramatic change in excited frequencies accompanied by a rapid increase in fractional amplitude; during this event it was essentially monoperiodic. We argue that GD 358's convection zone was much thinner in 1996 than in 2006, and we interpret this as a result of a short-lived increase in its surface temperature. In addition, we find strong evidence of oblique pulsation using two sets of evenly split triplets in the 2006 data. This marks the first time that oblique pulsation has been identified in a variable white dwarf star.Delaware Asteroseismic Research CenterNational Science Foundation AST-0909107, AST-0607840Norman Hackerman Advanced Research Program 003658-0255-2007Crystal Trust FoundationMt. Cuba ObservatoryUniversity of DelawareAstronom

Periodic variations in the O-C diagrams of five pulsation frequencies of the DB white dwarf EC 20058-5234

Variations in the pulsation arrival time of five independent pulsation frequencies of the DB white dwarf EC 20058−5234 individually imitate the effects of reflex motion induced by a planet or companion but are inconsistent when considered in unison. The pulsation frequencies vary periodically in a 12.9 year cycle and undergo secular changes that are inconsistent with simple neutrino plus photon-cooling models. The magnitude of the periodic and secular variations increases with the period of the pulsations, possibly hinting that the corresponding physical mechanism is located near the surface of the star. The phase of the periodic variations appears coupled to the sign of the secular variations. The standards for pulsation-timing-based detection of planetary companions around pulsating white dwarfs, and possibly other variables such as subdwarf B stars, should be re-evaluated. The physical mechanism responsible for this surprising result may involve a redistribution of angular momentum or a magnetic cycle. Additionally, variations in a supposed combination frequency are shown to match the sum of the variations of the parent frequencies to remarkable precision, an expected but unprecedented confirmation of theoretical predictions.Web of Scienc

A Pilot Study Investigating the Effect of the Supervision-Questioning-Feedback Model of Supervision on Stimulating Critical Thinking in Speech-Language Pathology Graduate Students

Purpose The purpose of this study was to investigate the effect of the supervision-questioning-feedback (SQF) model of supervision on critical thinking in graduate students studying speech-language pathology. The researchers hypothesized that students who were provided with the SQF model of supervision would score higher than students who received the non-SQF (NSQF) style of supervision on the selected critical thinking measures. Method Seventeen out of 24 first semester graduate students in speech-language pathology completing their on-site university-based clinical practicum experience consented to participate in the study. Of the 17 participating first semester students, 9 were randomly assigned to 1 of 3 SQF trained supervisors, and the other 8 were randomly assigned to 1 of 2 NSQF trained supervisors for the duration of 1 semester. Additionally, 3 out of 24 fourth semester graduate students completing their off-site externship experience and their supervisors consented to participate in the study. Four additional study participants served as independent SQF-trained raters charged with the task of analyzing video recorded student-supervisor conferences to determine whether the SQF model of supervision was being implemented. Prior to and at the conclusion of the clinical experience, all participating students completed two measures of critical thinking: (1) California Critical Thinking Skills Test (CCTST) and (2) two Simucase® clinical simulations. At the conclusion of the clinical experience, seventeen out of 20 participating students (11/12 SQF students and 6/8 NSQF students) completed a post-survey rating their supervisory experience . Results For participating first semester students, there were no overall statistically significant differences between SQF and NSQF groups as measured by pre to post completion of (1) CCTST (p=.544) and (2) two Simucase® clinical simulations (p=.781). The 3 participating fourth semester students who received the SQF model of supervision also showed no statistically significant differences on pre to post completion of the (1) CCTST (p=.827) and (2) two Simucase® virtual cases (p=.879). Results from SQF ratings revealed variability in the implementation of the SQF model across supervisors with a moderate level of inter-rater agreement. Results from post surveys completed by students showed that students preferred the SQF model of supervision over the NSQF model (p=.044). Conclusion Results from this preliminary study indicated that the SQF model did not influence the overall outcomes on the selected critical thinking measures. Student preference for the SQF model may support existing evidence that learning clinicians want to be actively engaged in the supervisory process. There were several limitations to this study including the small sample size, variability in the implementation of the SQF model across supervisors, sensitivity of the selected critical thinking measures, and timing of post-intervention procedures. Further investigation of the effects of SQF on students’ critical thinking is warranted

Timing by Stellar Pulsations as an Exoplanet Discovery Method

The stable oscillations of pulsating stars can serve as accurate timepieces, which may be monitored for the influence of exoplanets. An external companion gravitationally tugs the host star, causing periodic changes in pulsation arrival times. This method is most sensitive to detecting substellar companions around the hottest pulsating stars, especially compact remnants like white dwarfs and hot subdwarfs, as well as delta Scuti variables (A stars). However, it is applicable to any pulsating star with sufficiently stable oscillations. Care must be taken to ensure that the changes in pulsation arrival times are not caused by intrinsic stellar variability; an external, light-travel-time effect from an exoplanet identically affects all pulsation modes. With more long-baseline photometric campaigns coming online, this method is yielding new detections of substellar companions.Comment: 9 pages, 2 figures: Invited review to appear in 'Handbook of Exoplanets,' Springer Reference Works, edited by Hans J. Deeg and Juan Antonio Belmont

Pulsational Mapping of Calcium Across the Surface of a White Dwarf

We constrain the distribution of calcium across the surface of the white dwarf star G29-38 by combining time series spectroscopy from Gemini-North with global time series photometry from the Whole Earth Telescope. G29-38 is actively accreting metals from a known debris disk. Since the metals sink significantly faster than they mix across the surface, any inhomogeneity in the accretion process will appear as an inhomogeneity of the metals on the surface of the star. We measure the flux amplitudes and the calcium equivalent width amplitudes for two large pulsations excited on G29-38 in 2008. The ratio of these amplitudes best fits a model for polar accretion of calcium and rules out equatorial accretion.Comment: Accepted to the Astrophysical Journal. 16 pages, 10 figures

The rate of cooling of the pulsating white dwarf star G117−-B15A: a new asteroseismological inference of the axion mass

We employ a state-of-the-art asteroseismological model of G117-B15A, the archetype of the H-rich atmosphere (DA) white dwarf pulsators (also known as DAV or ZZ Ceti variables), and use the most recently measured value of the rate of period change for the dominant mode of this pulsating star to derive a new constraint on the mass of axion, the still conjectural non-barionic particle considered as candidate for dark matter of the Universe. Assuming that G117-B15A is truly represented by our asteroseismological model, and in particular, that the period of the dominant mode is associated to a pulsation g-mode trapped in the H envelope, we find strong indications of the existence of extra cooling in this star, compatible with emission of axions of mass m_a \cos^2 \beta = 17.4^{+2.3}_{-2.7} meV.Comment: 9 pages, 5 figures and 3 tables. Accepted for publication in MNRA