Estimating the economic benefits of regional ocean observing systems

We develop a methodology to estimate the potential economic benefits from new investments in regional coastal ocean observing systems in US waters, and apply this methodology to generate preliminary estimates of such benefits. The approach focuses on potential economic benefits from coastal ocean observing information within ten geographic regions encompassing all coastal waters of the United States, and within a wide range of industrial and recreational activities including recreational fishing and boating, beach recreation, maritime transportation, search and rescue operations, spill response, marine hazards prediction, offshore energy, power generation, and commercial fishing. Our findings suggest that annual benefits to users from the deployment of ocean observing systems are likely to run in the multiple $100s of millions of dollars per year. The project results should be considered first-order estimates that are subject to considerable refinement as the parameters of regional observing systems are better defined, and as our understanding of user sectors improves.Funding was provided by the Office of Naval Research under Grant No. N00014-02-1-1037

A Population of Dipper Stars from the Transiting Exoplanet Survey Satellite Mission

Dipper stars are a classification of young stellar objects that exhibit dimming variability in their light curves, dropping in brightness by 10-50%, likely induced by occultations due to circumstellar disk material. This variability can be periodic, quasi-periodic, or aperiodic. Dipper stars have been discovered in young stellar associations via ground-based and space-based photometric surveys. We present the detection and characterization of the largest collection of dipper stars to date: 293 dipper stars, including 234 new dipper candidates. We have produced a catalog of these targets, which also includes young stellar variables that exhibit predominately bursting-like variability and symmetric variability (equal parts bursting and dipping). The total number of catalog sources is 414. These variable sources were found in a visual survey of TESS light curves, where dipping-like variability was observed. We found a typical age among our dipper sources of <5 Myr, with the age distribution peaking at ~2 Myr, and a tail of the distribution extending to ages older than 20 Myr. Regardless of the age, our dipper candidates tend to exhibit infrared excess, which is indicative of the presence of disks. TESS is now observing the ecliptic plane, which is rich in young stellar associations, so we anticipate many more discoveries in the TESS dataset. A larger sample of dipper stars would enhance the census statistics of light curve morphologies and dipper ages.Comment: 19 pages, 11 figures, 1 table (included in latex source), accepted for publication in ApJ

RAPID: Collaborative Commanding and Monitoring of Lunar Assets

RAPID (Robot Application Programming Interface Delegate) software utilizes highly robust technology to facilitate commanding and monitoring of lunar assets. RAPID provides the ability for intercenter communication, since these assets are developed in multiple NASA centers. RAPID is targeted at the task of lunar operations; specifically, operations that deal with robotic assets, cranes, and astronaut spacesuits, often developed at different NASA centers. RAPID allows for a uniform way to command and monitor these assets. Commands can be issued to take images, and monitoring is done via telemetry data from the asset. There are two unique features to RAPID: First, it allows any operator from any NASA center to control any NASA lunar asset, regardless of location. Second, by abstracting the native language for specific assets to a common set of messages, an operator may control and monitor any NASA lunar asset by being trained only on the use of RAPID, rather than the specific asset. RAPID is easier to use and more powerful than its predecessor, the Astronaut Interface Device (AID). Utilizing the new robust middleware, DDS (Data Distribution System), developing in RAPID has increased significantly over the old middleware. The API is built upon the Java Eclipse Platform, which combined with DDS, provides platform-independent software architecture, simplifying development of RAPID components. As RAPID continues to evolve and new messages are being designed and implemented, operators for future lunar missions will have a rich environment for commanding and monitoring assets

101 Eclipsing Quadruple Star Candidates Discovered in TESS Full Frame Images

We present our second catalog of quadruple star candidates, containing 101 systems discovered in TESS Full-Frame Image data. The targets were initially detected as eclipsing binary stars with the help of supervised machine learning methods applied to sectors Sectors 1 through 54. A dedicated team of citizen scientists subsequently identified through visual inspection two sets of eclipses following two different periods. All 101 systems presented here pass comprehensive photocenter motion tests confirming that both sets of eclipses originate from the target star. Some of the systems exhibit prominent eclipse time variations suggesting dynamical interactions between the two component binary stars. One target is an eclipsing quintuple candidate with a (2+1)+2 hierarchical configuration, such that the (2+1) subsystem produces eclipses on the triple orbit as well. Another has recently been confirmed as the second shortest period quadruple reported to date. This catalog provides ephemerides, eclipse depths and durations, sample statistics, and highlights potentially interesting targets for future studies.Comment: 38 pages, 21 figures, 2 tables. Table with targets available online at MNRA

Mutual optimism and war

W hy do states fight costly wars when less costly negotiated settlements are possible? Must there not be some mutually agreeable alternative to war that can produce the same result without incurring the social loss? Could not decision makers agree to distribute the disputed territory or assets in a way consistent with their beliefs about the likely outcome of conflict, saving both sides significant death and destruction? In this article, we address one specific rationalist answer to these questions. As Blainey (1988) intimates, the high hopes on the eve of war suggest a sad conclusion: wars only occur when both rivals believe they can achieve more through fighting than through peaceful means. How might this be so? Obviously, when two countries are involved in a war, if one side wins then the other loses. We might then conclude that at least one side, in particular the loser, would prefer some peaceful method of resolving the dispute if she were certain of the outcome. But war is an uncertain process. Given this uncertainty, the leaders of the two countries must each form expectations about the results of a conflict to guide their decision making. The Mark Fey is associate professor of political science, 109E Harkness Hall, University of Rochester, Rochester, NY 14627 (mark.fey@ rochester.edu). Kristopher W. Ramsay is assistant professor of politics, 033 Corwin Hall, Princeton University, Princeton, NJ 08544 ([email protected]). Earlier versions of this article were presented at the University of Rochester, Columbia University, and NYU. We thank Scott Ashworth, Bruce Bueno de Mesquita, Songying Fang, Tanisha Fazal, Erik Gartzke, Shigeo Hirano, Adam Meirowitz, John Patty, Pablo Pinto, Robert Powell, Quinn Ramsay, Anne Sartori, Curt Signorino, Branislav Slantchev, Allan Stam, Randy Stone, and Robert Walker, as well as other seminar participants. We would also like to thank the editor of the AJPS and two anonymous reviewers for helpful comments. Any remaining errors are our own. Kris Ramsay acknowledges financial support from NSF grant SES-0413381

TIC 168789840: A Sextuply-Eclipsing Sextuple Star System

We report the discovery of a sextuply-eclipsing sextuple star system from TESS data, TIC 168789840, also known as TYC 7037-89-1, the first known sextuple system consisting of three eclipsing binaries. The target was observed in Sectors 4 and 5 during Cycle 1, with lightcurves extracted from TESS Full Frame Image data. It was also previously observed by the WASP survey and ASAS-SN. The system consists of three gravitationally-bound eclipsing binaries in a hierarchical structure of an inner quadruple system with an outer binary subsystem. Follow-up observations from several different observatories were conducted as a means of determining additional parameters. The system was resolved by speckle interferometry with a 0."42 separation between the inner quadruple and outer binary, inferring an estimated outer period of ~2 kyr. It was determined that the fainter of the two resolved components is an 8.217 day eclipsing binary, which orbits the inner quadruple that contains two eclipsing binaries with periods of 1.570 days and 1.306 days. MCMC analysis of the stellar parameters has shown that the three binaries of TIC 168789840 are "triplets", as each binary is quite similar to the others in terms of mass, radius, and Teff. As a consequence of its rare composition, structure, and orientation, this object can provide important new insight into the formation, dynamics, and evolution of multiple star systems. Future observations could reveal if the intermediate and outer orbital planes are all aligned with the planes of the three inner eclipsing binaries

Pravastatin for early-onset pre-eclampsia:a randomised, blinded, placebo-controlled trial

Objective: Women with pre-eclampsia have elevated circulating levels of soluble fms-like tyrosine kinase-1 (sFlt-1). Statins can reduce sFlt-1 from cultured cells and improve pregnancy outcome in animals with a pre-eclampsia-like syndrome. We investigated the effect of pravastatin on plasma sFlt-1 levels during pre-eclampsia. Design: Blinded (clinician and participant), proof of principle, placebo-controlled trial. Setting: Fifteen UK maternity units. Population: We used a minimisation algorithm to assign 62 women with early-onset pre-eclampsia (24 +0–31 +6 weeks of gestation) to receive pravastatin 40 mg daily (n = 30) or matched placebo (n = 32), from randomisation to childbirth. Primary outcome: Difference in mean plasma sFlt-1 levels over the first 3 days following randomisation. Results: The difference in the mean maternal plasma sFlt-1 levels over the first 3 days after randomisation between the pravastatin (n = 27) and placebo (n = 29) groups was 292 pg/ml (95% CI −1175 to 592; P = 0.5), and over days 1–14 was 48 pg/ml (95% CI −1009 to 913; P = 0.9). Women who received pravastatin had a similar length of pregnancy following randomisation compared with those who received placebo (hazard ratio 0.84; 95% CI 0.50–1.40; P = 0.6). The median time from randomisation to childbirth was 9 days [interquartile range (IQR) 5–14 days] for the pravastatin group and 7 days (IQR 4–11 days) for the placebo group. There were three perinatal deaths in the placebo-treated group and no deaths or serious adverse events attributable to pravastatin. Conclusions: We found no evidence that pravastatin lowered maternal plasma sFlt-1 levels once early-onset pre-eclampsia had developed. Pravastatin appears to have no adverse perinatal effects. Tweetable abstract: Pravastatin does not improve maternal plasma sFlt-1 or placental growth factor levels following a diagnosis of early preterm pre-eclampsia #clinicaltrial finds