153,287 research outputs found
Incentives for Sabotage in Vertically Related Industries
We show that the incentives a vertically integrated supplier may have to disadvantage or "sabotage" the activities of downstream rivals vary with both the type of sabotage and the nature of downstream competition. Cost-increasing sabotage is typically profitable under both Cournot and Bertrand competition. In contrast, demand-reducing sabotage is often profitable under Cournot competition, but unprofitable under Bertrand competition. Incentives for sabotage can vary non-monotonically with the degree of product differentiation.Regulation, Vertical Integration, Access Pricing, Sabotage
Nuclear quantum effects in water exchange around lithium and fluoride ions
We employ classical and ring polymer molecular dynamics simulations to study
the effect of nuclear quantum fluctuations on the structure and the water
exchange dynamics of aqueous solutions of lithium and fluoride ions. While we
obtain reasonably good agreement with experimental data for solutions of
lithium by augmenting the Coulombic interactions between the ion and the water
molecules with a standard Lennard-Jones ion-oxygen potential, the same is not
true for solutions of fluoride, for which we find that a potential with a
softer repulsive wall gives much better agreement. A small degree of
destabilization of the first hydration shell is found in quantum simulations of
both ions when compared with classical simulations, with the shell becoming
less sharply defined and the mean residence time of the water molecules in the
shell decreasing. In line with these modest differences, we find that the
mechanisms of the exchange processes are unaffected by quantization, so a
classical description of these reactions gives qualitatively correct and
quantitatively reasonable results. We also find that the quantum effects in
solutions of lithium are larger than in solutions of fluoride. This is partly
due to the stronger interaction of lithium with water molecules, partly due to
the lighter mass of lithium, and partly due to competing quantum effects in the
hydration of fluoride, which are absent in the hydration of lithium.Comment: 12 pages, 8 figure
CSF sTREM2: Marking the tipping point between preclinical AD and dementia?
Biomarkers for Alzheimer's disease (AD) have improved our understanding of the temporal sequence of biological events that lead to AD dementia (Jack et al, 2013). AD is characterized neuropathologically by amyloid plaques comprised of the amyloidâβ peptide and neurofibrillary tangles comprised of tau. Brain amyloid deposition, as evidenced by a decline in amyloidâβ peptide 42 (Aβ42) in the cerebrospinal fluid (CSF) or by binding of amyloid PET ligands, is thought to be a key initiating event in AD and begins many years prior to the onset of dementia. A rise in CSF tau and phosphorylated tau in the setting of Aβ deposition appears to reflect neurodegeneration and also begins years prior to the onset of dementia but after Aβ deposition has begun to accumulate. Individuals with âpreclinical AD,â that is, normal cognition but abnormal AD biomarkers, have a much higher risk for developing AD dementia but may remain cognitively normal for years (Vos et al, 2013). While deposition of amyloid and formation of tau tangles are necessary for AD to occur, it is likely that additional events involving inflammation or other processes contribute to crossing the tipping point from preclinical AD to AD dementia. Current efforts are aimed at defining the biomarker(s) that best predict the transition from cognitive normality to abnormality. A biomarker that is closely associated with the onset of cognitive decline could help us to understand the biological events that connect amyloid deposition and tangle formation to cognitive decline and could have significant practical value in AD diagnosis and clinical trial design
Achieving High Organization Performance through Servant Leadership
This empirical paper investigates whether a servant leader can develop a corporate culture that attracts or develops other servant leaders. Using the survey developed by Barbuto and Wheeler (2006), servant leader characteristics in managers were measured at three high-performing organizations. Results indicate that servant leaders can develop a culture of followers who are servant leaders themselves. This is one of the few studies to empirically test the model of servant leadership in an organizational environment. The success these servant leaders have achieved in a for-profit, demanding environment suggests this leadership style is viable for adoption by other firms
Mean-Field Theory of Water-Water Correlations in Electrolyte Solutions
Long-range ion induced water-water correlations were recently observed in
femtosecond elastic second harmonic scattering experiments of electrolyte
solutions. To further the qualitative understanding of these correlations, we
derive an analytical expression that quantifies ion induced dipole-dipole
correlations in a non-interacting gas of dipoles. This model is a logical
extension of Debye-H\"uckel theory that can be used to qualitatively understand
how the combined electric field of the ions induces correlations in the
orientational distributions of the water molecules in an aqueous solution. The
model agrees with results from molecular dynamics simulations and provides an
important starting point for further theoretical work
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