204 research outputs found
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Managerial compensation incentives and merger waves
This paper examines the relation between executive compensation incentives and the nature of merger transactions inside and outside of merger waves. We find that the sensitivity of CEO wealth to firm risk, vega, increases the likelihood of merger transactions outside of waves, but is unrelated to merger frequency inside wave periods. CEOs whose compensation is more closely tied to firm risk make better performing acquisitions when they acquire outside of merger waves, but this is not the case for in-wave deals, suggesting that underperformance of acquiring firms during waves can be attributed in part to ineffective compensation incentives. We also find that the cross-sectional dispersion of acquirers’ returns is higher for in-wave acquisitions relative to acquisitions made outside a wave, suggesting that out-wave acquisitions are characterized by lower uncertainty of future stock price returns. This is again restricted to high vega CEOs during out-wave periods
Incentive compensation vs. SOX: evidence from corporate acquisition decisions
We empirically examine the impact of incentive compensation on the riskiness of acquisition decisions before and after the passage of Sarbanes-Oxley Act (SOX). Controlling for confounding events, firm characteristics and industry fixed effects, we find a substantial change in the relation between equity-related compensation and acquisition risk post-SOX stemming from a previously unidentified shift in the effectiveness of executive stock options to control managerial risk aversion. Not only has incentive compensation failed to offset the adverse impact of SOX on risk-taking activity but it has also significantly altered managerial incentives. The decrease in acquisition risk post-SOX cannot be solely attributed to changes in the structure of executive compensation but it additionally stems from the way managers perceive compensation-based incentives in the new regulatory environment. The results are robust to different measures of acquisition risk and alternative definitions of incentive compensation
Litigating the Public Sector Equality Duty: The Story So Far
This paper considers the development and judicial application of the Public Sector Equality Duty now found in section 149 Equality Act 2010, previously in a variety of forms in the Race Relations Act 1976, the Disability Discrimination Act 1995 and the Sex Discrimination Act 1975. It identifies a number of emerging themes in the jurisprudence concerned, in particular, with the relationship between the PSED and Wednesbury review, the extent of the information-gathering obligation it imposes, the delegability of PSED decision-making and the timing of PSED challenge. It then considers the uncertainties which remain including, in particular, the application of the duty to various categories of decision-making, and concludes by assessing the impact of the PSED on challenges to ‘cuts’ cases arising from the reductions to public sector funding, and on domestic equality jurisprudence
Longitudinal thalamic white and gray matter changes associated with visual hallucinations in Parkinson’s disease
Objective: Visual hallucinations are common in
Parkinson’s disease (PD) and associated with worse
outcomes. Large-scale network imbalance is seen in
PD-associated hallucinations, but mechanisms remain
unclear. As the thalamus is critical in controlling cortical
networks, structural thalamic changes could underlie
network dysfunction in PD hallucinations.
Methods: We used whole-brain fixel-based analysis
and cortical thickness measures to examine longitudinal
white and grey matter changes in 76 patients with PD
(15 hallucinators, 61 non-hallucinators) and 26 controls
at baseline, and after 18 months. We compared white
matter and cortical thickness, adjusting for age, gender,
time-between-scans and intracranial volume. To assess
thalamic changes, we extracted volumes for 50 thalamic
subnuclei (25 each hemisphere) and mean fibre crosssection (FC) for white matter tracts originating in each
subnucleus and examined longitudinal change in PDhallucinators versus non-hallucinators.
Results: PD hallucinators showed white matter changes
within the corpus callosum at baseline and extensive
posterior tract involvement over time. Less extensive
cortical thickness changes were only seen after followup. White matter connections from the right medial
mediodorsal magnocellular thalamic nucleus showed
reduced FC in PD hallucinators at baseline followed
by volume reductions longitudinally. After follow-up,
almost all thalamic subnuclei showed tract losses in PD
hallucinators compared with non-hallucinators.
Interpretation: PD hallucinators show white matter
loss particularly in posterior connections and in thalamic
nuclei, over time with relatively preserved cortical
thickness. The right medial mediodorsal thalamic
nucleus shows both connectivity and volume loss in
PD hallucinations. Our findings provide mechanistic
insights into the drivers of network imbalance in PD
hallucinations and potential therapeutic targets
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Incentive compensation vs SOX: evidence from corporate acquisition decisions
In this paper, we use the introduction of the Sarbanes-Oxley Act in 2002 to assess the impact of executive option and stock grants on corporate acquisition decisions. Amongst its many innovations, the Sarbanes-Oxley Act (SOX) has limited the value and effect of equity-related compensation. We find strong evidence of a shift in the factors driving acquisitions post-SOX. Specifically, while bid premiums have fell irrespectively of the type of acquirer, highly incentivised managers have become more risk-averse after the passage of the Act. Investors also appear to have recognised the effect of a change in equity-related pay. Both market response to acquisition announcements and post-acquisition performance have been improved after the introduction of SOX but these cannot be attributed to firms that grant high levels of incentive compensation to their managers. Our results are robust to a number of explanatory factors and confounding events in the post-SOX period
Comparison of UK paediatric consultants’ participation in child health research between 2011 and 2015
Objective To identify whether there have been changes over time in the capacity of paediatric consultants to undertake research and if the activity differs between men and women. Design Comparison of data from two surveys of UK paediatric consultants. Subjects UK consultant members of the Royal College of Paediatrics and Child Health. Interventions Surveys carried out in 2011 and 2015. Main outcome measures The proportion of consultants with allocated time in job plans for research, academic appointments, postgraduate qualifications, publications, grant funding and supervision of PhD students. Results The 2015 survey demonstrated 20% of consultants had one or more programmed activities (PAs) for research, but the average paid PA for research was 0.39 PA. Between the surveys, the proportion of consultants with honorary contracts had declined, and the proportion with a PhD or MDRes was 32% in 2011 compared with 26% in 2015 (p<0.001). In 2015, only 12% of consultants had at least one current grant. In 2011 and 2015, 51% and 54% respectively of consultants had not authored a publication in the preceding 2 years. In 2015, 92% of consultants were not currently supervising a PhD student, and 88% had never supervised a PhD student. In 2015, 25% of men and 12% of women had PAs for research (p<0.001). Women were less likely to hold an honorary or primary academic contract, have authored a publication or supervised a PhD student (all p<0.001). Conclusions Research activity among paediatric consultants remains low, particularly among women
Fibre-specific white matter reductions in Parkinson’s hallucinations and visual dysfunction
Objective: To investigate the microstructural and macrostructural white matter changes that accompany visual hallucinations and low visual performance in Parkinson’s disease, a risk factor for Parkinson’s dementia.
Methods: We performed fixel-based analysis, a novel technique that provides metrics of specific fibre-bundle populations within a voxel (or fixel). Diffusion MRI data was acquired from patients with Parkinson’s disease (n=105, of which 34 low visual performers and 19 hallucinators) and age-matched controls (n=35). We used whole brain fixel-based analysis to compare micro-structural differences in fibre density (FD), macro-structural differences in fibre bundle cross-section (FC) and the combined fibre density and cross-section metric (FDC) across all white matter fixels. We then performed a tract of interest analysis comparing the most sensitive FDC metric across 11 tracts within the visual system.
Results: Patients with Parkinson’s disease hallucinations exhibited macrostructural changes (reduced FC) within the splenium of the corpus callosum and the left posterior thalamic radiation compared to patients without hallucinations. Whilst there were no significant changes in FD, we found large reductions in the combined FDC metric in Parkinson’s hallucinators within the splenium (>50% reduction compared to non-hallucinators). Patients with Parkinson’s disease and low visual performance showed widespread microstructural and macrostructural changes within the genu and splenium of the corpus callosum, bilateral posterior thalamic radiations and the left inferior fronto-occipital fasciculus.
Conclusions: We demonstrate specific white matter tract degeneration affecting posterior thalamic tracts in patients with Parkinson’s disease with hallucinations and low visual performance, providing direct mechanistic support for attentional models of visual hallucinations
Visual dysfunction predicts cognitive impairment and white matter degeneration in Parkinson's disease
Visual dysfunction predicts dementia in Parkinsons disease (PD), but whether this translates to structural change is not known. We aimed to identify longitudinal white matter changes in patients with Parkinsons disease and low visual function and also in those who developed mild cognitive impairment (MCI). We used fixel-based analysis to examine longitudinal white matter change in PD. Diffusion MRI and clinical assessments were performed in 77 patients at baseline (22 low visual function /55 intact vision; and 13 MCI, 13 MCI converters /51 normal cognition) and 25 controls and again after 18 months. We compared micro-structural changes in fibre density, macro-structural changes in fibre bundle cross-section (FC) and combined fibre density and cross-section across white matter, adjusting for age, gender and intracranial volume. Patients with Parkinsons and visual dysfunction showed worse cognitive performance at follow up and were more likely to develop MCI compared with those with normal vision (p=0.008). Parkinsons with poor visual function showed diffuse micro-structural and macro-structural changes at baseline, whereas those with MCI showed fewer baseline changes. At follow-up, Parkinsons with low visual function showed widespread macrostructural changes, involving the fronto-occipital fasciculi, external capsules, and middle cerebellar peduncles bilaterally. No longitudinal change was seen in baseline MCI or in MCI converters, even when the two groups were combined. Parkinsons patients with poor visual function show increased white matter damage over time, providing further evidence for visual function as a marker of imminent cognitive decline
Public and patient involvement in child health research and service improvements: a survey of hospital doctors
Objectives: To determine whether paediatricians are supported by their organisations to encourage patient and public involvement (PPI) in research activities and clinical improvement work, the challenges they face and how they think these could be addressed by the Royal College of Paediatrics and Child Health (RCPCH). Design: A survey. Setting: UK consultant paediatricians and staff associate specialist and specialty (SAS) doctors who are members of RCPCH. Main outcome measures: The proportion of respondents who said that PPI was central to research and service improvements in their organisation, the type of local support for PPI activity, challenges in undertaking PPI and the support members wanted from RCPCH. Results: There was a response rate of 44.4% (n=1924). In their organisation, 29.1% of respondents stated PPI was central to research and 36.1% to service improvement; 46% were unaware of support for PPI and 15% said there was no support. The main challenges for PPI activity were a lack of clinician time, local support and funding. Respondents wanted RCPCH to advocate for protected time for PPI, provide access to PPI groups and deliver guidance and training. Conclusions: The majority of paediatricians feel unsupported to undertake PPI activity by their local organisation. The RCPCH has a key role to enable all paediatricians to work with children, young people and their carers to improve the quality of research and clinical services as demonstrated by RCPCH's ongoing activity in these crucial and important areas
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