On the Jacquet Conjecture on the Local Converse Problem for p-adic GL_n

Based on previous results of Jiang, Nien and the third author, we prove that any two minimax unitarizable supercuspidals of GL_N that have the same depth and central character admit a special pair of Whittaker functions. This result gives a new reduction towards a final proof of Jacquet's conjecture on the local converse problem for GL_N. As a corollary of our result, we prove Jacquet's conjecture for GL_N, when N is prime

Coupled ocean–atmosphere interactions between the Madden–Julian oscillation and synoptic-scale variability over the warm pool

A principal component analysis of the combined fields of sea surface temperature (SST) and surface zonal and meridional wind reveals the dominant mode of intraseasonal (30-70-day) co-variability during northern winter in the tropical Eastern Hemisphere is that of the Madden-Julian Oscillation (MJO). Regression calculations show that the submonthly (30-day high-pass filtered) surface wind variability is significantly modulated during the MJO. Regions of increased (decreased) submonthly surface wind variability propagate eastward, approximately in phase with the intraseasonal surface westerly (easterly) anomalies of the MJO. Due to the dependence of the surface latent heat flux on the magnitude of the total wind speed, this systematic modulation of the submonthly surface wind variability produces a significant component in the intraseasonal latent heat flux anomalies, which partially cancels the latent heat flux anomalies due to the slowly varying intraseasonal wind anomalies, particularly south of 10S. A method is derived that demodulates the submonthly surface wind variability from the slowly varying intraseasonal wind anomalies. This method is applied to the wind forcing fields of a one-dimensional ocean model. The model response to this modified forcing produces larger intraseasonal SST anomalies than when the model is forced with the observed forcing over large areas of the southwest Pacific Ocean and southeast Indian Ocean during both phases of the MJO. This result has implications for accurate coupled modeling of the MJO. A similar calculation is applied to the surface shortwave flux, but intraseasonal modulation of submonthly surface shortwave flux variability does not appear to be important to the dynamics of the MJO

Design and Implementation of an RF front end for the NeXtRAD radar system

This dissertation presents the design of the RF front end for use on the NeXtRAD radar system. The system is intended for research purposes to investigate potential target detection benefits to be derived from a multistatic, dual-band (X- and L-band), polarimetric radar architecture, particularly within dense clutter environments such as the maritime environment. By examining the high-level system requirements and objectives, requirement specifications for the RF front end were derived and a suitable architecture, making use of commercial off-the-shelf components, proposed. This architecture was modified in order to meet cost constraints - subsequently offering reduced levels of functionality but suitable for an initial build. Using this modified RF front end architecture, design verification and system analysis was conducted, both analytically and with the aid of SystemVue, in order to predict both the front end and overall radar detection performance. Once the front end design was found to be satisfactory, it was built and tested in a laboratory environment. Test results revealed a general improvement in performance when compared with the design predictions, yielding peak transmitter power levels in excess of 61dBm at L-band, and 54dBm at X-band. Some non-conformances were also identified, but these were as a result of component problems and not system design. Since the front end could not yet be integrated into the radar, performance modelling was repeated using the final lab test results. This indicated a negligible improvement in receiver single-pulse signal-to-noise ratio, but confirmed that the system performed as predicted. Based on the lab test results, it was concluded that the 'as-built' front end design closely matched the design goals and would be suitable for eventual integration into the first revision of the NeXtRAD system. It was, however, recommended that a concerted effort be made to secure funding to implement the original front end architecture in order to achieve the full system functionality originally desired

On the sharpness of the bound for the Local Converse Theorem of p-adic GLprime

We introduce a novel ultrametric on the set of equivalence classes of cuspidal irreducible representations of a general linear group GL(N) over a nonarchimedean local field, based on distinguishability by twisted gamma factors. In the case that N is prime and the residual characteristic is greater than or equal to N/2, we prove that, for any natural number i at most N/2, there are pairs of cuspidal irreducible representations whose logarithmic distance in this ultrametric is precisely i. This implies that, under the same conditions on N, the bound N/2 in the Local Converse Theorem for GL(N) is sharp

Depressive Symptoms and Alcohol-Related Problems Among College Students: A Moderated-Mediated Model of Mindfulness and Drinking to Cope

Objective: In college student samples, the association between depressive symptoms and alcohol-related problems has been found to be mediated by drinking-to-cope motives. Mindfulness-based interventions suggest that mindfulness may attenuate the conditioned response of using substances in response to negative emotional states, and trait mindfulness has been shown to be a protective factor associated with experiencing fewer alcohol-related problems. In the present study, we examined trait mindfulness as a moderator of the indirect associations of depressive symptoms on alcohol-related problems via drinking-to-cope motives. Method: Participants were undergraduate students at a large, southeastern university in the United States who drank at least once in the previous month (n = 448). Participants completed an online survey regarding their personal mental health, coping strategies, trait mindfulness, and alcohol use behaviors. The majority of participants were female (n = 302; 67.4%), identified as being either White non Hispanic (n = 213; 47.5%) or African American (n = 119; 26.6%), and reported a mean age of 22.74 (SD = 6.81) years. Further, 110 (25%) participants reported having a previous and/or current experience with mindfulness mediation. Results: As hypothesized, the indirect effects from depressive symptoms to alcohol-related problems via drinking-to-cope motives were weaker among individuals reporting higher levels of mindfulness than among individuals reporting lower and average levels of mindfulness. Conclusions: The present study suggests a possible mechanism through which mindfulness-based interventions may be efficacious among college students: decoupling the associations between depressive symptoms and drinking-to-cope motives

Diagnostic error in the emergency department: learning from national patient safety incident report analysis.

BACKGROUND: Diagnostic error occurs more frequently in the emergency department than in regular in-patient hospital care. We sought to characterise the nature of reported diagnostic error in hospital emergency departments in England and Wales from 2013 to 2015 and to identify the priority areas for intervention to reduce their occurrence. METHODS: A cross-sectional mixed-methods design using an exploratory descriptive analysis and thematic analysis of patient safety incident reports. Primary data were extracted from a national database of patient safety incidents. Reports were filtered for emergency department settings, diagnostic error (as classified by the reporter), from 2013 to 2015. These were analysed for the chain of events, contributory factors and harm outcomes. RESULTS: There were 2288 cases of confirmed diagnostic error: 1973 (86%) delayed and 315 (14%) wrong diagnoses. One in seven incidents were reported to have severe harm or death. Fractures were the most common condition (44%), with cervical-spine and neck of femur the most frequent types. Other common conditions included myocardial infarctions (7%) and intracranial bleeds (6%). Incidents involving both delayed and wrong diagnoses were associated with insufficient assessment, misinterpretation of diagnostic investigations and failure to order investigations. Contributory factors were predominantly human factors, including staff mistakes, healthcare professionals' inadequate skillset or knowledge and not following protocols. CONCLUSIONS: Systems modifications are needed that provide clinicians with better support in performing patient assessment and investigation interpretation. Interventions to reduce diagnostic error need to be evaluated in the emergency department setting, and could include standardised checklists, structured reporting and technological investigation improvements