Short Sale Constraints and Stock Returns

Stocks can be overpriced when short sale constraints bind. We study the costs of short selling equities, 1926-1933, using the publicly observable market for borrowing stock. Some stocks are sometimes expensive to short, and it appears that stocks enter the borrowing market when shorting demand is high. We find that stocks that are expensive to short or which enter the borrowing market have high valuations and low subsequent returns, consistent with the overpricing hypothesis. Size-adjusted returns are one to two percent lower per month for new entrants, and despite high costs it is profitable to short them.

The Effect of Suspension-Line Length on Viking Parachute Inflation Loads

Analytical calculations have considered the effect on maximum load of increasing the suspension-line length on the Viking parachute. Results indicate that unfurling time is increased to 1.85 seconds from 1.45 seconds, and that maximum loads are increased approximately 5 percent with an uncertainty of -4 percent to +3 percent

Historic clinical trial external control arm provides actionable GEN-1 efficacy estimate before a randomized trial

PURPOSE: To inform continued development of the novel immune agent GEN-1, we compared ovarian cancer patients\u27 end points from a neoadjuvant single-arm phase IB study with those of similar historic clinical trial (HCT) patients who received standard neoadjuvant chemotherapy. METHODS: Applying OVATION-1 trial (ClinicalTrials.gov identifier: NCT02480374) inclusion and exclusion criteria to Medidata HCT data, we identified historical trial patients for comparison. Integrating patient-level Medidata historic trial data (N = 41) from distinct neoadjuvant ovarian phase I-III trials with patient-level OVATION-1 data (N = 18), we selected Medidata patients with similar baseline characteristics as OVATION-1 patients using propensity score methods to create an external control arm (ECA). RESULTS: Fifteen OVATION-1 patients (15 of 18, 83%) were matched to 15 (37%, 15 of 41) Medidata historical trial control patients. Matching attenuated preexisting differences in attributes between the groups. The median progression-free survival time was not reached by the OVATION-1 group and was 15.8 months (interquartile range, 11.40 months to nonestimable) for the ECA. The hazard of progression was 0.53 (95% CI, 0.16 to 1.73), favoring GEN-1 patients. Compared with ECA patients, OVATION-1 patients had more nausea, fatigue, chills, and infusion-related reactions. CONCLUSION: Comparing results of a single-arm early-phase trial to those of a rigorously matched HCT ECA yielded insights regarding comparative efficacy prior to a randomized controlled trial. The effect size estimate itself informed both the decision to continue development and the randomized phase II trial (ClinicalTrials.gov identifier: NCT03393884) sample size. The work illustrates the potential of HCT data to inform drug development

A systematic review of factors that affect uptake of community-based health insurance in low-income and middle-income countries

Background: Low-income and middle-income countries (LMICs) have difficulties achieving universal financial protection, which is primordial for universal health coverage. A promising avenue to provide universal financial protection for the informal sector and the rural populace is community-based health insurance (CBHI). We systematically assessed and synthesised factors associated with CBHI enrolment in LMICs. Methods: We searched PubMed, Scopus, ERIC, PsychInfo, Africa-Wide Information, Academic Search Premier, Business Source Premier, WHOLIS, CINAHL, Cochrane Library, conference proceedings, and reference lists for eligible studies available by 31 October 2013; regardless of publication status. We included both quantitative and qualitative studies in the review. Results: Both quantitative and qualitative studies demonstrated low levels of income and lack of financial resources as major factors affecting enrolment. Also, poor healthcare quality (including stock-outs of drugs and medical supplies, poor healthcare worker attitudes, and long waiting times) was found to be associated with low CBHI coverage. Trust in both the CBHI scheme and healthcare providers were also found to affect enrolment. Educational attainment (less educated are willing to pay less than highly educated), sex (men are willing to pay more than women), age (younger are willing to pay more than older individuals), and household size (larger households are willing to pay more than households with fewer members) also influenced CBHI enrolment. Conclusion: In LMICs, while CBHI schemes may be helpful in the short term to address the issue of improving the rural population and informal workers’ access to health services, they still face challenges. Lack of funds, poor quality of care, and lack of trust are major reasons for low CBHI coverage in LMICs. If CBHI schemes are to serve as a means to providing access to health services, at least in the short term, then attention should be paid to the issues that militate against their success

Generation and screening of a comprehensive \u3ci\u3eMycobacterium avium\u3c/i\u3e subsp. \u3ci\u3eparatuberculosis\u3c/i\u3e transposon mutant bank

Mycobacterium avium subsp. paratuberculosis (MAP) is the etiologic agent of Johne’s Disease in ruminants. This enteritis has significant economic impact and world wide distribution. Vaccination is one of the most cost effective infectious disease control measures. Unfortunately, current vaccines reduce clinical disease and shedding, but are of limited efficacy and do not provide long-term protective immunity. Several strategies have been followed to mine the MAP genome for virulence determinants that could be applied to vaccine and diagnostic assay developent. In this study, a comprehensive mutant bank of 13,536 MAP K-10 Tn5367 mutants (P\u3e95% )was constructed and screened in vitro for phenotypes related to virulence. This strategy was designated to maximize identification of genes important to MAP pathogenesis without relying on studies of other mycobacterial species that may not translate into similar effects in MAP. This bank was screened for mutants with colony morphology alterations, susceptibility to D-cycloserine, impairment in siderophore production or secretion, reduced cell association, and decreased biofilm and clump formation. Mutants with interesting phenotypes were analyzed by PCR, Southern blotting and DNA sequencing to determine transposon insertion sites. These insertion sites mapped up stream from the MAP1152-MAP1156 cluster, internal to either the Mod operon gene MAP1566 or within the coding sequence of lsr2, and several intergenic regions. Growth curves in broth cultures, invasion assays and kinetics of survival and replication in primary bovine macrophages were also determined. The ability of vectors carrying Tn5370 to generate stable MAP mutants was also investigated

Development of a Kemp\u27s Ridley Sea Turtle Stock Assessment Model

We developed a Kemp’s ridley (Lepidochelys kempii) stock assessment model to evaluate the relative contributions of conservation efforts and other factors toward this critically endangered species’ recovery. The Kemp’s ridley demographic model developed by the Turtle Expert Working Group (TEWG) in 1998 and 2000 and updated for the binational recovery plan in 2011 was modified for use as our base model. The TEWG model uses indices of the annual reproductive population (number of nests) and hatchling recruitment to predict future annual numbers of nests on the basis of a series of assumptions regarding age and maturity, remigration interval, sex ratios, nests per female, juvenile mortality, and a putative ‘‘turtle excluder device effect’’ multiplier starting in 1990. This multiplier was necessary to fit the number of nests observed in 1990 and later. We added the effects of shrimping effort directly, modified by habitat weightings, as a proxy for all sources of anthropogenic mortality. Additional data included in our model were incremental growth of Kemp’s ridleys marked and recaptured in the Gulf of Mexico, and the length frequency of stranded Kemp’s ridleys. We also added a 2010 mortality factor that was necessary to fit the number of nests for 2010 and later (2011 and 2012). Last, we used an empirical basis for estimating natural mortality, on the basis of a Lorenzen mortality curve and growth estimates. Although our model generated reasonable estimates of annual total turtle deaths attributable to shrimp trawling, as well as additional deaths due to undetermined anthropogenic causes in 2010, we were unable to provide a clear explanation for the observed increase in the number of stranded Kemp’s ridleys in recent years, and subsequent disruption of the species’ exponential growth since the 2009 nesting season. Our consensus is that expanded data collection at the nesting beaches is needed and of high priority, and that 2015 be targeted for the next stock assessment to evaluate the 2010 event using more recent nesting and in-water data

Endovascular strategy or open repair for ruptured abdominal aortic aneurysm: one-year outcomes from the IMPROVE randomized trial.

AIMS: To report the longer term outcomes following either a strategy of endovascular repair first or open repair of ruptured abdominal aortic aneurysm, which are necessary for both patient and clinical decision-making. METHODS AND RESULTS: This pragmatic multicentre (29 UK and 1 Canada) trial randomized 613 patients with a clinical diagnosis of ruptured aneurysm; 316 to an endovascular first strategy (if aortic morphology is suitable, open repair if not) and 297 to open repair. The principal 1-year outcome was mortality; secondary outcomes were re-interventions, hospital discharge, health-related quality-of-life (QoL) (EQ-5D), costs, Quality-Adjusted-Life-Years (QALYs), and cost-effectiveness [incremental net benefit (INB)]. At 1 year, all-cause mortality was 41.1% for the endovascular strategy group and 45.1% for the open repair group, odds ratio 0.85 [95% confidence interval (CI) 0.62, 1.17], P = 0.325, with similar re-intervention rates in each group. The endovascular strategy group and open repair groups had average total hospital stays of 17 and 26 days, respectively, P < 0.001. Patients surviving rupture had higher average EQ-5D utility scores in the endovascular strategy vs. open repair groups, mean differences 0.087 (95% CI 0.017, 0.158), 0.068 (95% CI -0.004, 0.140) at 3 and 12 months, respectively. There were indications that QALYs were higher and costs lower for the endovascular first strategy, combining to give an INB of £3877 (95% CI £253, £7408) or €4356 (95% CI €284, €8323). CONCLUSION: An endovascular first strategy for management of ruptured aneurysms does not offer a survival benefit over 1 year but offers patients faster discharge with better QoL and is cost-effective. CLINICAL TRIAL REGISTRATION: ISRCTN 48334791

source. Short Sale Constraints and Stock Returns

JEL No. G14 Stocks can be overpriced when short sale constraints bind. We study the costs of short selling equities, 1926-1933, using the publicly observable market for borrowing stock. Some stocks are sometimes expensive to short, and it appears that stocks enter the borrowing market when shorting demand is high. We find that stocks that are expensive to short or which enter the borrowing market have high valuations and low subsequent returns, consistent with the overpricing hypothesis. Size-adjusted returns are one to two percent lower per month for new entrants, and despite high costs it is profitable to short them