Employee Satisfaction, Firm Value and Firm Productivity

We examine whether self-reported employee satisfaction is associated with higher firm valuation and productivity. Using a sample of firms from Fortune magazine’s list of "100 Best Companies to Work For", companies in which employees report high levels of satisfaction, we find that these firms have valuations that are significantly greater than both their respective industry medians and matched firms. The firms in our sample also exhibit greater levels of productivity and efficiency. Thus, successful efforts in increasing employee satisfaction appear to enhance overall firm productivity, which is subsequently rewarded by investors through higher equity values.Employee satisfaction, firm value, firm productivity

CEO Confidence and Stock Returns

In this research, I explore whether announcements of CEO confidence contain new information for investors. Information asymmetry implies that insiders such as Chief Executive Officers should have better information regarding the firm prospects than the average stock market participant. Thus, announcements of CEO perceptions may provide valuable insights to investors. Utilizing The Conference Board quarterly measures of CEO confidence and CEO six-month economic outlook, I find significant correlations between changes in CEO outlook and the announcement date returns on three major stock market indexes. These correlations are larger and more significant for indexes of smaller companies, implying announcements of CEO confidence provide unique and valuable information to stock markets.CEO Confidence, Consumer Confidence, Stock Returns, Asymmetric Information

Employee Satisfaction And Shareholder Returns

We hypothesize that satisfied employees lead to higher returns for shareholders.  In particular, we investigate whether inclusion on Fortune magazine’s list of “100 Best Companies to Work For” leads to increases in wealth for shareholders.  We find no announcement effect associated with the list release date.  Although we do find that a subset of firms named to the list in one year generate higher returns (than a matched sample) the following year, we conclude that, ex ante, investors would be unable to consistently profit from any information provided by inclusion on the list.  Tests of returns of companies that are dropped from the Fortune list indicate no abnormal performance

Evolution of host resistance towards pathogen exclusion: the role of predators

Question: Can increased host resistance drive a pathogen to extinction? Do more complex ecosystems lead to significantly different evolutionary behaviour and new potential extinctions? Mathematical method: Merging host-parasite models with predator-prey models. Analytically studying evolution using adaptive dynamics and trade-off and invasion plots, and carrying out numerical simulations. Key assumptions: Mass action (general mixing). All individuals of a given phenotype are identical. Only prey vulnerable to infection. Mutations are small and rare (however, the assumption on the size of mutation is relaxed later). In simulations, very small (negligible) populations are at risk of extinction. Conclusions: The presence of the predator can significantly change evolutionary outcomes for host resistance to a pathogen and can create branching points where none occurred previously. The pathogen (and sometimes the predator) is protected from exclusion if we take mutations to be arbitrarily small; however, relaxing the assumption on mutation size can lead to its exclusion. Increased resistance can drive the predator and/or pathogen to extinction depending on inter-species dynamics, such as the predator's preference for infected prey. Predator co-evolution can move exclusion boundaries and prevent the predator's own extinction if its rate of mutation is high enough (with respect to that of the prey)

In vitro osteoclast formation and resorption of silicon-substituted hydroxyapatite ceramics.

Materials that participate in bone remodeling at the implant/tissue interface represent a modern tissue engineering approach with the aim of balancing implant resorption and nascent tissue formation. Silicon-substituted hydroxyapatite (SiHA) ceramics are capable of stimulating new bone formation, but little is known about their interaction with osteoclasts (OC). The effects of soluble silicate and SiHA on OCs were investigated in this study. Soluble silicate below 500 μM did not stimulate cell metabolism at 4 days or alter resorption area at 7 days on calcium phosphate discs. On sintered ceramics, OC numbers were similar on HA, Si0.3 HA (0.5 wt % Si) and Si0.5 HA (1.2 wt % Si) after 21 days in vitro, but actin ring sealing zone morphology on SiHA resembled that commonly found on bone or on carbonate-substituted hydroxyapatite (CHA). Smaller and thicker actin rings on SiHA as compared to HA were probably the result of altered surface chemistry and solubility differences. The more stable sealing zones and increased lattice solubility likely contributed to increased individual pit volumes observed on Si0.5 HA. The delayed formation of OCs on Si0.5 HA (lower numbers at day 14) excludes earlier differentiation as a possible mechanism of increased individual OC pit volumes at later times (day 21). Materials characterization of Si containing biomaterials remains paramount as the Si type and amounts can subsequently impact downstream OC behaviour in a complex manner.Funded by - National Science Foundation Graduate Research Fellowship (RJF). Grant Number: DGE-1042796 - Cambridge International Scholarship from the Cambridge Overseas Trusts (RJF) - National Institute for Health Research (RAB)This is the author accepted manuscript. The final version is available from Wiley via http://dx.doi.org/10.1002/jbm.a.3547

Using a Bone-Conduction Headset to Improve Speech Discrimination in Children With Otitis Media With Effusion.

The recommended management for children with otitis media with effusion (OME) is 'watchful waiting' before considering grommet surgery. During this time speech and language, listening skills, quality of life, social skills, and outcomes of education can be jeopardized. Air-conduction (AC) hearing aids are problematic due to fluctuating AC hearing loss. Bone-conduction (BC) hearing is stable, but BC hearing aids can be uncomfortable. Both types of hearing aids are costly. Given the high prevalence of OME and the transitory nature of the accompanying hearing loss, cost-effective solutions are needed. The leisure industry has developed relatively inexpensive, comfortable, high-quality BC headsets for transmission of speech or music. This study assessed whether these headsets, paired with a remote microphone, improve speech discrimination for children with OME. Nineteen children aged 3 to 6 years receiving recommended management in the United Kingdom for children with OME participated. Word-discrimination thresholds were measured in a sound-treated room in quiet and with 65 dB(A) speech-shaped noise, with and without a headset. The median threshold in quiet (N = 17) was 39 dB(A) (range: 23-59) without a headset and 23 dB(A) (range: 9-35) with a headset (Z = -3.519, p < .001). The median threshold in noise (N = 19) was 59 dB(A) (range: 50-63) without a headset and 45 dB(A) (range: 32-50) with a headset (Z = -3.825, p < .001). Thus, the use of a BC headset paired with a remote microphone significantly improved speech discrimination in quiet and in noise for children with OME.The main source of funding for this study was the Cambridge Hearing Trust. T. H. B. was awarded the British Association of Paediatricians in Audiology Prize in 2017, and J. E. M. and M. S.-C. were jointly granted the Stuart Gatehouse Applied Research Grant 2015 by the British Society of Audiology, both toward the Bone conduction In Glue ear study

Collagen fibre implant for tendon and ligament biological augmentation. In vivo study in an ovine model.

PURPOSE: Although most in vitro studies indicate that collagen is a suitable biomaterial for tendon and ligament tissue engineering, in vivo studies of implanted collagen for regeneration of these tissues are still lacking. The objectives of this study were the following: (1) to investigate the regeneration of the central third of the ovine patellar tendon using implants made of an open array of collagen fibres (reconstituted, extruded bovine collagen); and (2) to compare two collagen crosslinking chemistries: carbodiimide and carbodiimide associated with ethyleneglycoldiglycidylether. METHODS: Forty-eight Welsh Mountain sheep were operated on their right hind leg. The central third of patellar tendon was removed and substituted with carbodiimide (n = 16) and carbodiimide-ethyleneglycoldiglycidylether-crosslinked implants (n = 16). In the control group the defect was left empty (n = 16). The central third of contralateral unoperated tendons was used as positive controls. Half of the sheep in each group were killed at 3- and 6-month time points. After proper dissection, tendon sub-units (medial, central and lateral) were tested to failure (n = 6 for each group), whilst 2 non-dissected samples were used for histology. RESULTS: Both the implants had significantly lower stress to failure and modulus with respect to native tendon at both 3- and at 6-month time points. The implants did not statistically differ in stress to failure, whilst carbodiimide-crosslinked implants had significantly higher modulus than carbodiimide-ethyleneglycoldiglycidylether-crosslinked implants both at 3 and at 6 months. Histology showed carbodiimide-crosslinked implants to have a better integration with the native tendon than carbodiimide-ethyleneglycoldiglycidylether-crosslinked implants. Carbodiimide-crosslinked implants appeared partially resorbed and showed increased tissue ingrowth with respect to carbodiimide-ethyleneglycoldiglycidylether-crosslinked implants. CONCLUSIONS: To deliver collagen implants as an open array of fibres allows optimal tendon-implant integration and good ingrowth of regenerated tissue. In the present study the resorption rate of both the examined implants was too low due to the high level of crosslinking. This led to only minor substitution of the implant with regenerated tissue, which in turn produced a low-strength implanted region. Further studies are needed to find the right balance between strength and resorption rate of collagen fibres