Managerial response to shareholder empowerment: evidence from majority- voting legislation changes

This paper studies how managers react to shareholder empowerment that makes the votes on shareholder proposals regarding majority-voting director elections binding. Exploiting staggered legislative changes that introduce such empowerment, we find that managers become more responsive by initiating majority voting through either management proposals or governance guidelines. Further results suggest compromised implementation: managers adopt provisions that give them greater control over the channel of implementation and allow them to retain directors who fail in elections. Managers show the greatest resistance to implementing majority-voting standards when shareholder value is likely to suffer more or benefit less from the legislation

The Neural Substrate of the Eureka Effect

The Eureka effect, also known as Aha effect, insight or epiphany, refers to the common experience of suddenly solving a problem. Here we study this effect in a pattern recognition paradigm that requires the segmentation of complex scenes and recognition of objects on the basis of Gestalt rules and prior knowledge. In the experiments both sensory evidence and prior knowledge were manipulated in order to obtain trials that do or do not converge towards a perceptual solution. Subjects had to detect objects in blurred scenes and signal recognition with manual responses. Neural dynamics were analysed with high density Electroencephalography (EEG) recordings. We determined changes in spectral distribution, coherence, phase locking and fractal dimension. The Eureka effect was associated with increased coherent oscillations in the alpha and theta band over widely distributed regions of the cortical mantle predominantly in the right hemisphere. This increase in coherence was associated with a decrease of beta band activity over parietal and central regions, and with a decrease of alpha band activity over frontal and occipital areas. In addition, there was a lateralized reduction of fractal dimensionality for activity recorded from the right hemisphere. These results suggest that the transition towards the solution of a perceptual task is mainly associated with a change of network dynamics in the right hemisphere that is characterized by enhanced coherence and reduced complexity. We propose that the Eureka effect requires cooperation of cortical regions involved in working memory, creative thinking and the control of attention

Essays on adaptation, innovation incentives and compensation structure

This thesis explores both theoretically and empirically how firms design employees’ compensation contracts to motivate them to work and to adapt to external changes under an informed principal framework. The first chapter analyzes how a principal, privately informed about the changing market condition, structures the agent’s incentive contract to inform and motivate her to adapt. The results show that a failure to overturn employees’ belief about the changing market condition could lead to insufficient adaptation. Further, a more pressing market condition induces earlier adaptation and greater information revelation. Finally, the compensation structure underpinning insufficient adaptation imposes a legacy problem due to excessive use of long-term incentives, which restrains the reconfiguration of the contract in place. Based on the first chapter, the second chapter aims to explain asymmetric contractual adjustment of CEO compensation, only upward but not downward. I argue that a principal, privately informed about the firm’s changing productive efficiency, uses contracts to provide the agent with not only working incentives but also information about her productivity. The principal commits to a back-loaded compensation plan with an increasing salary or with an increasing short-term performance pay. Such rigid contracts achieve greater efficiency by inducing more efforts from the agent through profit sharing. The third chapter, co-authored with Peggy Huang and Moqi Xu, finds CEO contracts explicitly account for subjective reviews in a new dataset of CEO contracts and stated reasons for compensation changes. Our results suggest that firms prefer to keep early R&D successes from the public and thus raise salaries for early R&D success not yet realized in performance measures. Consistent with this explanation, standalone salary increases predict better long-run portfolio and stock returns, but only following positive subjective evaluations and in firms with high R&D investment

Phasic cholinergic signaling promotes emergence of local gamma rhythms in excitatory–inhibitory networks

Recent experimental results have shown that the detection of cues in behavioral attention tasks relies on transient increases of acetylcholine (ACh) release in frontal cortex and cholinergically driven oscillatory activity in the gamma frequency band (Howe et al. Journal of Neuroscience, 2017, 37, 3215). The cue‐induced gamma rhythmic activity requires stimulation of M1 muscarinic receptors. Using biophysical computational modeling, we show that a network of excitatory (E) and inhibitory (I) neurons that initially displays asynchronous firing can generate transient gamma oscillatory activity in response to simulated brief pulses of ACh. ACh effects are simulated as transient modulation of the conductance of an M‐type K+ current which is blocked by activation of muscarinic receptors and has significant effects on neuronal excitability. The ACh‐induced effects on the M current conductance, gKs, change network dynamics to promote the emergence of network gamma rhythmicity through a Pyramidal‐Interneuronal Network Gamma mechanism. Depending on connectivity strengths between and among E and I cells, gamma activity decays with the simulated gKs transient modulation or is sustained in the network after the gKs transient has completely dissipated. We investigated the sensitivity of the emergent gamma activity to synaptic strengths, external noise and simulated levels of gKs modulation. To address recent experimental findings that cholinergic signaling is likely spatially focused and dynamic, we show that localized gKs modulation can induce transient changes of cellular excitability in local subnetworks, subsequently causing population‐specific gamma oscillations. These results highlight dynamical mechanisms underlying localization of ACh‐driven responses and suggest that spatially localized, cholinergically induced gamma may contribute to selectivity in the processing of competing external stimuli, as occurs in attentional tasks.Recent experiments showed that cholinergic signaling in the prefrontal cortex is fast and spatially localized in the context of attentional behavioral tasks. The cholinergic transients also generated gamma frequency oscillations that contributed to successful attentional performance. Using computational modeling, we show that transient cholinergic modulation of neural excitability induced the emergence of transient synchronous gamma activity from a background of asynchronous firing in excitatory–inhibitory neural networks.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162747/2/ejn14744.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162747/1/ejn14744_am.pd

PF-DMD: Physics-fusion dynamic mode decomposition for accurate and robust forecasting of dynamical systems with imperfect data and physics

The DMD (Dynamic Mode Decomposition) method has attracted widespread attention as a representative modal-decomposition method and can build a predictive model. However, the DMD may give predicted results that deviate from physical reality in some scenarios, such as dealing with translation problems or noisy data. Therefore, this paper proposes a physics-fusion dynamic mode decomposition (PFDMD) method to address this issue. The proposed PFDMD method first obtains a data-driven model using DMD, then calculates the residual of the physical equations, and finally corrects the predicted results using Kalman filtering and gain coefficients. In this way, the PFDMD method can integrate the physics-informed equations with the data-driven model generated by DMD. Numerical experiments are conducted using the PFDMD, including the Allen-Cahn, advection-diffusion, and Burgers' equations. The results demonstrate that the proposed PFDMD method can significantly reduce the reconstruction and prediction errors by incorporating physics-informed equations, making it usable for translation and shock problems where the standard DMD method has failed

Uncertainty Analysis on Risk Assessment of Water Inrush in Karst Tunnels

An improved attribute recognition method is reviewed and discussed to evaluate the risk of water inrush in karst tunnels. Due to the complex geology and hydrogeology, the methodology discusses the uncertainties related to the evaluation index and attribute measure. The uncertainties can be described by probability distributions. The values of evaluation index and attribute measure were employed through random numbers generated by Monte Carlo simulations and an attribute measure belt was chosen instead of the linearity attribute measure function. Considering the uncertainties of evaluation index and attribute measure, the probability distributions of four risk grades are calculated using random numbers generated by Monte Carlo simulation. According to the probability distribution, the risk level can be analyzed under different confidence coefficients. The method improvement is more accurate and feasible compared with the results derived from the attribute recognition model. Finally, the improved attribute recognition method was applied and verified in Longmenshan tunnel in China

Inert shell coating for enhanced laser refrigeration of nanoparticles: application in levitated optomechanics

We report on a study exploring the design of nanoparticles that can enhance their laser refrigeration efficiency for applications in levitated optomechanics. In particular, we developed lanthanide-doped nanocrystals with an inert shell coating and compared their performance with bare nanocrystals. While optically levitated, we studied the refrigeration of both types of nanoparticles while varying the pressure. We found that the core-shell design shows an improvement in the minimum final temperature: a fourth of the core-shell nanoparticles showed a significant cooling compared to almost none of the bare nanoparticles. Furthermore, we measured a core-shell nanoparticle cooling down to a temperature of 147 K at 26 mbar in the underdamped regime. Our study is a first step towards engineering nanoparticles that are suitable for achieving absolute (centre-of-mass and internal temperature) cooling in levitation, opening new avenues for force sensing and the realization of macroscopic quantum superpositions.Comment: Any comments are welcome

Asymptotic results for conditional measures of association of a random sum

Asymptotic results are obtained for several conditional measures of association. The chosen random variables are the first two order statistics and the total sum within a random sum. Many of the results have confirmed the "one-jump"property of the risk model. Non-trivial limits are obtained when the dependence among the first two order statistics is considered. Our results help in understanding the extreme behaviour of well-known reinsurance treaties that involve only few large claims. Interestingly, the Pearson product-moment correlation coefficient between the first two order statistics provides an alternative procedure to estimate the tail index of the underlying distribution

The rodent models of arteriovenous fistula

Arteriovenous fistulas (AVFs) have long been used as dialysis access in patients with end-stage renal disease; however, their maturation and long-term patency still fall short of clinical needs. Rodent models are irreplaceable to facilitate the study of mechanisms and provide reliable insights into clinical problems. The ideal rodent AVF model recapitulates the major features and pathology of human disease as closely as possible, and pre-induction of the uremic milieu is an important addition to AVF failure studies. Herein, we review different surgical methods used so far to create AVF in rodents, including surgical suturing, needle puncture, and the cuff technique. We also summarize commonly used evaluations after AVF placement. The aim was to provide recent advances and ideas for better selection and induction of rodent AVF models. At the same time, further improvements in the models and a deeper understanding of AVF failure mechanisms are expected