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Although scholars have long emphasized the importance of entrepreneurs to long-term growth prospects, entrepreneurship often receives less attention by policy makers than traditional industrial recruitment efforts as regional growth engines. The effects of entrepreneurship may be more subtle than the latter approaches, but business creation can have significant effects across both space and time. This article first sketches the important relationship between innovation, entrepreneurship, and growth and then empirically assesses the relationship between entrepreneurship and job growth across U.S. labor market areas and counties. Three key findings emerge. First, entrepreneurship is systematically related to job growth; furthermore, this relationship increases in intensity over time. Second, entrepreneurship has the greatest impact on the county in which it occurs but also generates positive spillovers for job growth in neighboring counties. Finally, the impact of entrepreneurship is greater in denser, more urbanized settings where such businesses can leverage the advantages of a thick marketplace.

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A patient with obstructive sleep apnea was monitored five times during three years while his weight fluctuated within a range of 26 kg. The number of apneas per hour of sleep varied from 59.6 at 111 kg of weight to 3.1 at 85 kg. The relation between apneas per hour of sleep and body weight was a logarithmic function. A modest decrease in weight was thus associated with a disproportionally larger decrease in the rate of apneas. Typical SaO 2 levels during the apneic episodes also had a logarithmic relation with body weight. Apnea-related sinus bradycardia and sinus tachycardia were only present at the highest weight. The results suggested that dieting and weight loss lead to an improvement in sleep apnea and related sequelae.Obstructive sleep apnea syndrome is characterized by a repetitive and periodic occlusion of the upper airway during sleep. The mechanisms involved in this disorder are not well understood at present. 1 Obesity is seen in the majority of patients with sleep apnea. Redundant tissue in the oropharyngeal airway associated with obesity is thought to be a contributing factor. Surgical intervention by tracheostomy or uvulo-palato-pharyngoplasty is the treatment of choice, especially in the presence of apneic-induced cardiac arrhythmias, but case reports have suggested improvement in the obstructive sleep apnea and related sequelae following weight loss. 2-4 The exact relation between this syndrome and body weight remains ambiguous, however, as previous reports are based on single observations following weight reduction. We have monitored the sleep of a patient with obstructive sleep apnea five times during the course of nearly three years while his weight fluctuated from 85 kg to 111 kg. A logarithmic relation between the rate of apneas during sleep and body weight is demonstrated by this patient. Case ReportA 52-year-old white man was referred for evaluation of uncontrolled daytime sleepiness. The patient reported a 19-year history of hypersomnia and falling asleep at inappropriate times. Symptoms were reported as relatively stable over the past ten years. The patient noted loud snoring and excessive sweating during sleep. Although he denied cataplexy, hypnagogic hallucinations and sleep paralysis, narcolepsy was diagnosed two years prior to our evaluation based solely on the reported hypersomnia.Physical examination revealed an obese man (173 cm tall, weighing 111 kg), extremely drowsy, but otherwise in no distress. Pertinent medical disorders included essential systemic

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We investigate the relationship between exposure to Hurricanes Katrina and/or Rita and mental health resilience by vulnerability status, with particular focus on the mental health outcomes of single mothers versus the general public. We advance a measurable notion of mental health resilience to disaster events. We also calculate the economic costs of poor mental health days added by natural disaster exposure. Negative binomial analyses show that hurricane exposure increases the expected count of poor mental health days for all persons by 18.7% (95% confidence interval [CI], 7.44-31.14%), and by 71.88% (95% CI, 39.48-211.82%) for single females with children. Monthly time-series show that single mothers have lower event resilience, experiencing higher added mental stress. Results also show that the count of poor mental health days is sensitive to hurricane intensity, increasing by a factor of 1.06 (95% CI, 1.02-1.10) for every billion (U.S.$) dollars of damage added for all exposed persons, and by a factor of 1.08 (95% CI, 1.03-1.14) for single mothers. We estimate that single mothers, as a group, suffered over $130 million in productivity loss from added postdisaster stress and disability. Results illustrate the measurability of mental health resilience as a two-dimensional concept of resistance capacity and recovery time. Overall, we show that natural disasters regressively tax disadvantaged population strata.

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We examine the contribution to economic growth of entrepreneurial “marketplace information” within a regional endogenous growth framework. Entrepreneurs are posited to provide an input to economic growth through the information revealed by their successes and failures. We empirically identify this information source with the regional variation in establishment births and deaths, which create geographic information asymmetries that influence subsequent entrepreneurial activity and economic growth. We find that local establishment birth and death rates are significantly and positively correlated with subsequent entrepreneurship for US counties. To account for the potential endogeneity caused by forward-looking entrepreneurs, we utilize instruments based on historic mining activity. We find that the information spillover component of local establishment birth and death rates have significant positive effects on subsequent entrepreneurship and employment growth for US counties and metropolitan areas. With the help of these intruments, we show that establishment births have a positive and significant effect on future employment growth within all counties, and that in line with the information hypothesis, local establishment death rates have a similar positive effect within metropolitan counties.