Affecting Change Synergistically: An Interpretative Case Study of Leadership Relationships at Southwest Airlines

As we move into the 21st century it becomes increasingly more important to move beyond what we have come to know as leadership--great man and position/authority-based, excellent management. Instead, what organizations are in need of is a postindustrial model of leadership. Rost defined 21st century leadership as an influence relationship among leaders and followers who intend real changes that reflect their mutual purposes (p. 102). This study sought to operationalize 21st century leadership in Southwest Airlines Co., a Texas-based corporation that is recognized as one of America\u27s most successful airlines. This company has a 22 year history, over 10,000 employees, and earned profits of $91 million in 1993. This research is an interpretative case study guided by open-ended interviews, observation and document analysis. Key informant interviews were held with Southwest Airlines employees from different levels and a variety of positions within the company to determine whether or not leadership relationships were involved in two major change efforts--an improvement in on-time performance and the perpetuation of Southwest\u27s spirited culture. This case study presents the people of Southwest Airlines as leaders and followers who intended, and accomplished two very real and substantive changes. These change efforts were based on multidirectional influence and reflective of the mutual purposes held by the individuals engaged in these synergistic leadership relationships. It was determined that the leaders and followers involved in these change efforts were successful because they collectively practiced postindustrial leadership

Asymmetry in the Qy Fluorescence and Absorption Spectra of Chlorophyll <i>a</i> Pertaining to Exciton Dynamics.

Significant asymmetry found between the high-resolution Q y emission and absorption spectra of chlorophyll-a is herein explained, providing basic information needed to understand photosynthetic exciton transport and photochemical reactions. The Q y spectral asymmetry in chlorophyll has previously been masked by interference in absorption from the nearby Q x transition, but this effect has recently been removed using extensive quantum spectral simulations or else by analytical inversion of absorption and magnetic circular dichroism data, allowing high-resolution absorption information to be accurately determined from fluorescence-excitation spectra. To compliment this, here, we measure and thoroughly analyze the high-resolution differential fluorescence line narrowing spectra of chlorophyll-a in trimethylamine and in 1-propanol. The results show that vibrational frequencies often change little between absorption and emission, yet large changes in line intensities are found, this effect also being strongly solvent dependent. Among other effects, the analysis in terms of four basic patterns of Duschinsky-rotation matrix elements, obtained using CAM-B3LYP calculations, predicts that a chlorophyll-a molecule excited into a specific vibrational level, may, without phase loss or energy relaxation, reemit the light over a spectral bandwidth exceeding 1,000 cm-1 (0.13 eV) to influence exciton-transport dynamics

Hydrodynamic limit of gradient exclusion processes with conductances

Fix a strictly increasing right continuous with left limits function W: \bb R \to \bb R and a smooth function \Phi : [l,r] \to \bb R, defined on some interval $[l,r]$ of \bb R, such that $0<b \le \Phi'\le b^{-1}$. We prove that the evolution, on the diffusive scale, of the empirical density of exclusion processes, with conductances given by $W$, is described by the weak solutions of the non-linear differential equation $\partial_t \rho = (d/dx)(d/dW) \Phi(\rho)$. We derive some properties of the operator $(d/dx)(d/dW)$ and prove uniqueness of weak solutions of the previous non-linear differential equation

The role of high-level calculations in the assignment of the Q-band spectra of chlorophyll

© 2014 AIP Publishing LLC. We recently established a novel assignment of the visible absorption spectrum of chlorophyll-a that sees the two components Qx and Qy of the low-energy Q band as being intrinsically mixed by non-adiabatic coupling. This ended 50 years debate as to the nature of the Q bands, with prior discussion poised only in the language of the Born-Oppenheimer and Condon approximations. The new assignment presents significant ramifications for exciton transport and quantum coherence effects in photosystems. Results from state of the art electronic structure calculations have always been used to justify assignments, but quantitative inaccuracies and systematic failures have historically limited usefulness. We examine the role of CAM-B3LYP time-dependent density-functional theory (TD-DFT) and Symmetry Adapted Cluster-Configuration Interaction (SAC-CI) calculations in first showing that all previous assignments were untenable, in justifying the new assignment, in making some extraordinary predictions that were vindicated by the new assignment, and in then identifying small but significant anomalies in the extensive experimental data record

Absorption-emission symmetry breaking and the different origins of vibrational structures of the 1Qy and 1Qx electronic transitions of pheophytin a

© 2019 Author(s). The vibrational structure of the optical absorption and fluorescence spectra of the two lowest-energy singlet electronic states (Qy and Qx) of pheophytin a were carefully studied by combining low-resolution and high-resolution spectroscopy with quantum chemical analysis and spectral modeling. Large asymmetry was revealed between the vibrational structures of the Qy absorption and fluorescence spectra, integrally characterized by the total Huang-Rhys factor and reorganization energy in absorption of SvibA = 0.43 ± 0.06, λA = 395 cm-1 and in emission of SvibE = 0.35 ± 0.06, λE = 317 cm-1. Time-dependent density-functional theory using the CAM-B3LYP, ωB97XD, and MN15 functionals could predict and interpret this asymmetry, with the exception of one vibrational mode per model, which was badly misrepresented in predicted absorption spectra; for CAM-B3LYP and ωB97XD, this mode was a Kekulé-type mode depicting aromaticity. Other computational methods were also considered but performed very poorly. The Qx absorption spectrum is broad and could not be interpreted in terms of a single set of Huang-Rhys factors depicting Franck-Condon allowed absorption, with Herzberg-Teller contributions to the intensity being critical. For it, CAM-B3LYP calculations predict that SvibA (for modes >100 cm-1) = 0.87 and λA = 780 cm-1, with effective x and y polarized Herzberg-Teller reorganization energies of 460 cm-1 and 210 cm-1, respectively, delivering 15% y-polarized intensity. However, no method was found to quantitatively determine the observed y-polarized contribution, with contributions of up to 50% being feasible

Insomnia as an Independent Predictor of Incident Cardiovascular Disease in HIV: Data from the Veterans Aging Cohort Study

Background: Insomnia is associated with increased cardiovascular disease (CVD) risk in the general population and is highly prevalent in people with HIV. The CVD risk conferred by insomnia in the HIV population is unknown. Methods: Using the Veterans Aging Cohort Study-Survey Cohort, insomnia symptoms were measured and dummy coded with the item, “Difficulty falling or staying asleep?” (5-point scale from no difficulty to bothers a lot). Incident CVD event ICD-9 codes (acute myocardial infarction, stroke, or coronary artery revascularization) were identified with VA and Medicare administrative data and VA fee-for-service data. Those with baseline CVD were excluded. Results: HIV-infected (N=3,108) veterans had a median follow-up time of 10.8 years, during which 267 CVD events occurred. Compared to HIV-infected veterans with no difficulty falling or staying asleep, HIV-infected veterans bothered a lot by insomnia symptoms had an increased risk of incident CVD after adjusting for demographics (HR=1.64, 95%CI=1.16-2.31, p=.005), CVD risk factors (HR=1.62, 95%CI=1.14-2.30, p=.007), additional potential confounders (hepatitis C infection, renal disease, anemia, alcohol use, cocaine use; HR=1.70, 95%CI=1.19-2.43, p=.003), and HIV-specific factors (HIV-1 RNA, CD4+ T-cell count, ART; HR=1.66, 95%CI=1.16-2.37, p=.005). Additional adjustment for non-benzodiazepine sleep medication (HR=1.62, 95%CI=1.13-2.32, p=.009) did not attenuate the association; however, it fell short of significance at p < .01 after adjustment for depressive symptoms (HR=1.51, 95%CI=0.98-2.32, p=.060) or antidepressant medication (HR=1.51, 95%CI=1.04-2.19, p=.031). Conclusion: Highly bothersome insomnia symptoms were significantly associated with incident CVD in HIV-infected veterans, suggesting that insomnia may be a novel, modifiable risk factor for CVD in HIV

Coxsackie and adenovirus receptor is a modifier of cardiac conduction and arrhythmia vulnerability in the setting of myocardial ischemia.

OBJECTIVES: The aim of this study was to investigate the modulatory effect of the coxsackie and adenovirus receptor (CAR) on ventricular conduction and arrhythmia vulnerability in the setting of myocardial ischemia. BACKGROUND: A heritable component in the risk of ventricular fibrillation during myocardial infarction has been well established. A recent genome-wide association study of ventricular fibrillation during acute myocardial infarction led to the identification of a locus on chromosome 21q21 (rs2824292) in the vicinity of the CXADR gene. CXADR encodes the CAR, a cell adhesion molecule predominantly located at the intercalated disks of the cardiomyocyte. METHODS: The correlation between CAR transcript levels and rs2824292 genotype was investigated in human left ventricular samples. Electrophysiological studies and molecular analyses were performed using CAR haploinsufficient (CAR(+/-)) mice. RESULTS: In human left ventricular samples, the risk allele at the chr21q21 genome-wide association study locus was associated with lower CXADR messenger ribonucleic acid levels, suggesting that decreased cardiac levels of CAR predispose to ischemia-induced ventricular fibrillation. Hearts from CAR(+/-) mice displayed slowing of ventricular conduction in addition to an earlier onset of ventricular arrhythmias during the early phase of acute myocardial ischemia after ligation of the left anterior descending artery. Expression and distribution of connexin 43 were unaffected, but CAR(+/-) hearts displayed increased arrhythmia susceptibility on pharmacological electrical uncoupling. Patch-clamp analysis of isolated CAR(+/-) myocytes showed reduced sodium current magnitude specifically at the intercalated disk. Moreover, CAR coprecipitated with NaV1.5 in vitro, suggesting that CAR affects sodium channel function through a physical interaction with NaV1.5. CONCLUSIONS: CAR is a novel modifier of ventricular conduction and arrhythmia vulnerability in the setting of myocardial ischemia. Genetic determinants of arrhythmia susceptibility (such as CAR) may constitute future targets for risk stratification of potentially lethal ventricular arrhythmias in patients with coronary artery disease