A duality between scattering poles and transmission eigenvalues in scattering theory.

In this paper, we develop a conceptually unified approach for characterizing and determining scattering poles and interior eigenvalues for a given scattering problem. Our approach explores a duality stemming from interchanging the roles of incident and scattered fields in our analysis. Both sets are related to the kernel of the relative scattering operator mapping incident fields to scattered fields, corresponding to the exterior scattering problem for the interior eigenvalues and the interior scattering problem for scattering poles.

The Impact of Administrative Burden on Academic Physicians: Results of a Hospital-Wide Physician Survey.

Purpose: To determine the characteristics of clinically active academic physicians most affected by administrative burden; the correlation between administrative burden, burnout, and career satisfaction among academic physicians; and the relative value and burden of specific administrative tasks.

Method: The authors analyzed data from the 2014 Massachusetts General Physicians Organization Survey. Respondents reported the percentage of time they spent on patient-related administrative duties and rated the value and burden associated with specific administrative tasks.

Rethinking the roles of CRP, cAMP, and sugar-mediated global regulation in the Vibrionaceae.

Many proteobacteria modulate a suite of catabolic genes using the second messenger cyclic 3', 5'-AMP (cAMP) and the cAMP receptor protein (CRP). Together, the cAMP-CRP complex regulates target promoters, usually by activating transcription. In the canonical model, the phosphotransferase system (PTS), and in particular the EIIA(Glc) component for glucose uptake, provides a mechanistic link that modulates cAMP levels depending on glucose availability, resulting in more cAMP and activation of alternative catabolic pathways when glucose is unavailable.

Growth on glucose decreases cAMP-CRP activity while paradoxically increasing intracellular cAMP in the light-organ symbiont Vibrio fischeri.

Proteobacteria often co-ordinate responses to carbon sources using CRP and the second messenger cyclic 3', 5'-AMP (cAMP), which combine to control transcription of genes during growth on non-glucose substrates as part of the catabolite-repression response. Here we show that cAMP-CRP is active and important in Vibrio fischeri during colonization of its host squid Euprymna scolopes. Moreover, consistent with a classical role in catabolite repression, a cAMP-CRP-dependent reporter showed lower activity in cells grown in media amended with glucose rather than glycerol.

Modeling Analysis of Signal Sensitivity and Specificity by Vibrio fischeri LuxR Variants.

The LuxR protein of the bacterium Vibrio fischeri belongs to a family of transcriptional activators that underlie pheromone-mediated signaling by responding to acyl-homoserine lactones (-HSLs) or related molecules. V. fischeri produces two acyl-HSLs, N-3-oxo-hexanoyl-HSL (3OC6-HSL) and N-octanoyl-HSL (C8-HSL), each of which interact with LuxR to facilitate its binding to a "lux box" DNA sequence, thereby enabling LuxR to activate transcription of the lux operon responsible for bioluminescence.