Richard Nixon’s Left Knee and Its Impact on American History

Richard Nixon injured his left knee in a limousine door while campaigning in North Carolina in 1960, resulting in septic arthritis that required a multi-day admission to Walter Reed Hospital. Still ill for the first presidential debate that fall, Nixon lost the contest based more on his appearance than his performance. Partly as a result of this debate, he was defeated by John F. Kennedy in the general election. Because of his leg wound, Nixon developed chronic DVTs in that limb, including a severe thrombus in 1974 that embolized to his lung, required surgery, and prevented him from testifying at the Watergate Trial. Episodes like this one highlight the value of studying the health of famous figures, where even the most minor injuries have the potential to influence world history

5-Year survival of pediatric anterior cruciate ligament reconstruction with living donor hamstring tendon grafts

Background: It is well accepted that there is a higher incidence of repeat anterior cruciate ligament (ACL) injuries in the pediatric population after ACL reconstruction (ACLR) with autograft tissue compared with adults. Hamstring autograft harvest may contribute to the risk for repeat ACL injuries in this high functional demand group. A novel method is the use of a living donor hamstring tendon (LDHT) graft from a parent; however, there is currently limited research on the outcomes of this technique, particularly beyond the short term. Purpose/Hypothesis: The purpose was to determine the medium-term survival of the ACL graft and the contralateral ACL (CACL) after primary ACLR with the use of an LDHT graft from a parent in those aged less than 18 years and to identify factors associated with subsequent ACL injuries. It was hypothesized that ACLR with the use of an LDHT provides acceptable midterm outcomes in pediatric patients. Study Design: Case series; Level of evidence, 4. Methods: Between 2005 and 2014, 247 (of 265 eligible) consecutive patients in a prospective database, having undergone primary ACLR with the use of an LDHT graft and aged less than 18 years, were included. Outcomes were assessed at a minimum of 2 years after surgery including data on ACL reinjuries, International Knee Documentation Committee (IKDC) scores, and current symptoms, as well as factors associated with the ACL reinjury risk were investigated. Results: Patients were reviewed at a mean of 4.5 years (range, 24-127 months [10.6 years]) after ACLR with an LDHT graft. Fifty-one patients (20.6%) sustained an ACL graft rupture, 28 patients (11.3%) sustained a CACL rupture, and 2 patients sustained both an ACL graft rupture and a CACL rupture (0.8%). Survival of the ACL graft was 89%, 82%, and 76% at 1, 2, and 5 years, respectively. Survival of the CACL was 99%, 94%, and 86% at 1, 2, and 5 years, respectively. Survival of the ACL graft was favorable in patients with Tanner stage 1-2 at the time of surgery versus those with Tanner stage 3-5 at 5 years (87% vs 69%, respectively; hazard ratio, 3.7; P = .01). The mean IKDC score was 91.7. A return to preinjury levels of activity was reported by 59.1%. Conclusion: After ACLR with an LDHT graft from a parent in those aged less than 18 years, a second ACL injury (ACL graft or CACL injury) occurred in 1 in 3 patients. The 5-year survival rate of the ACL graft was 76%, and the 5-year survival rate of the CACL was 86%. High IKDC scores and continued participation in sports were maintained over the medium term. Importantly, there was favorable survival of the ACL graft in patients with Tanner stage 1-2 compared with patients with Tanner stage 3-5 over 5 years. Patients with Tanner stage 1-2 also had a significantly lower incidence of second ACL injuries over 5 years compared with those with Tanner stage 3-5, occurring in 1 in 5 patients. Thus, an LDHT graft from a parent is an appropriate graft for physically immature children

Multiproduct mergers and quality competition

We investigate mergers in markets where quality dierences between products are central and rms may reposition their product lines by adding or removing products of dierent qualities following a merger. Such mergers are ma- terially dierent from those studied in the existing literature. Mergers without synergies may exhibit a product-mix eect which raises consumer surplus, but only when the pre-merger industry structure satises certain observable features. Post-merger synergies may lower consumer surplus. The level of, and changes in, the Herndahl-Hirschman Index may give a misleading assessment of how a merger aects consumers. A merger may benet some outsiders but harm others

Platform design when sellers use pricing algorithms

Using both economic theory and Artificial Intelligence (AI) pricing algorithms, we investigate the ability of a platform to design its marketplace to promote competition, improve consumer surplus, and even raise its own profits. We allow sellers to use Q-learning algorithms (a common reinforcement-learning technique from the computer-science literature) to devise pricing strategies in a setting with repeated interactions, and consider the effect of steering policies that reward firms that cut prices with additional exposure to consumers. Overall, the evidence from our experiments suggests that platform design decisions can meaningfully benefit consumers even when algorithmic collusion might otherwise emerge but that achieving these gains may require more than the simplest steering policies when algorithms value the future highly. We also find that policies that raise consumer surplus can raise the profits of the platform, depending on the platform’s revenue model. Finally, we document several learning challenges faced by the algorithms

Dr. Bobbie Bailey & Family Performance Center Anniversary Celebration

The School of Music is proud to welcome back to campus several of our esteemed alumni for a special recital as part of the Bailey Performance Center 10th anniversary celebration! The School of Music celebrates the opening of the Bailey Performance Center with featured performances by the KSU Wind Ensemble Brass and Percussion, Symphony Orchestra, Chamber Singers, University Chorale and Chamber Singers Alumni Choir, along with pianist Robert Henry, soprano Jana Young, and more!https://digitalcommons.kennesaw.edu/musicprograms/1969/thumbnail.jp

Global guideline for the diagnosis and management of cryptococcosis: an initiative of the ECMM and ISHAM in cooperation with the ASM

Cryptococcosis is a major worldwide disseminated invasive fungal infection. Cryptococcosis, particularly in its most lethal manifestation of cryptococcal meningitis, accounts for substantial mortality and morbidity. The breadth of the clinical cryptococcosis syndromes, the different patient types at-risk and affected, and the vastly disparate resource settings where clinicians practice pose a complex array of challenges. Expert contributors from diverse regions of the world have collated data, reviewed the evidence, and provided insightful guideline recommendations for health practitioners across the globe. This guideline offers updated practical guidance and implementable recommendations on the clinical approaches, screening, diagnosis, management, and follow-up care of a patient with cryptococcosis and serves as a comprehensive synthesis of current evidence on cryptococcosis. This Review seeks to facilitate optimal clinical decision making on cryptococcosis and addresses the myriad of clinical complications by incorporating data from historical and contemporary clinical trials. This guideline is grounded on a set of core management principles, while acknowledging the practical challenges of antifungal access and resource limitations faced by many clinicians and patients. More than 70 societies internationally have endorsed the content, structure, evidence, recommendation, and pragmatic wisdom of this global cryptococcosis guideline to inform clinicians about the past, present, and future of care for a patient with cryptococcosis

Borrelia burgdorferi Requires the Alternative Sigma Factor RpoS for Dissemination within the Vector during Tick-to-Mammal Transmission

While the roles of rpoSBb and RpoS-dependent genes have been studied extensively within the mammal, the contribution of the RpoS regulon to the tick-phase of the Borrelia burgdorferi enzootic cycle has not been examined. Herein, we demonstrate that RpoS-dependent gene expression is prerequisite for the transmission of spirochetes by feeding nymphs. RpoS-deficient organisms are confined to the midgut lumen where they transform into an unusual morphotype (round bodies) during the later stages of the blood meal. We show that round body formation is rapidly reversible, and in vitro appears to be attributable, in part, to reduced levels of Coenzyme A disulfide reductase, which among other functions, provides NAD+ for glycolysis. Our data suggest that spirochetes default to an RpoS-independent program for round body formation upon sensing that the energetics for transmission are unfavorable

Essays in microeconomic theory

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Economics, c1999.Includes bibliographical references (p. 70-72).Three essays are presented which explore how strategic decision-making on a micro level translates into macro effects. Careful attention is paid to how asymmetric information and free-riding exert strong influences on t.he behavior of individuals. In the first chapter, a simple model of open-source software development is presented. It is found that either too little development or redundant development effort can occur. While any redundant research effort grows slowly with the size of the community, projects for which user valuations arc sufficiently extreme, such as solutions to the Year 2000 Computer Problem (Y2K), will result in significant waste relative to a traditional closed-source environment. Correlations between value and cost are shown to resolve the empirical puzzle as to why some extremely useful and fairly simple software docs not get written while more complex software sometimes docs. It is shown that a modular design can improve or worsen the performance of an open-source community. In the second chapter, an industry is considered in which new firms require time to learn whether they have the "right stuff" to grow in size and profitability in the long run. The critical input market ( that for skilled labor) is imperfectly competitive. By extending the literate on nonstationary dynamic bargaining, analysis is performed on a set of intertemporal externalities exerted by future parties on today's parties, and vice versa. The results suggest why, even if firms are able to write detailed contingent contracts with their current employees, inefficient levels of firm entry will generally exist. The theory also sheds some light on the continuing debate over the contribution of small firms to economic growth. In the third and final chapter, players in a. war of attrition care about the identity of the winner, even when they lose. In particular, a three player war of attrition is considered . Two "team" players enjoy a. fraction of their valuation when their partner wins. The remaining, ''solo" player benefits only by winning the war. Imposing team symmetry, the solo player drops out more quickly then either team player. The incentive to avoid fighting costs by free riding on a teammate is outweighed by a strategic commitment effect. Team players thus continue to fight even when they have no chance of winning a subsequent two-player subgame with the solo player. Examining limiting results, when the "caring coefficient" between t.he team players is small, a selection result obtains: The solo player drops out immediately, allowing the team players to then compete in a standard two-player war of attrition.Justin Pappas Johnson.Ph.D