Look at Me Now: What Attracts U.S. Shareholders?

This paper investigates the underlying determinants of home bias using a comprehensive data set on U.S. investors' aggregate holdings of every foreign stock. Among those foreign stocks that are not listed on U.S. exchanges, which account for more than 96 percent of our usable data sample, we find that U.S. investors prefer firms with characteristics associated with greater information transparency, such as stronger home-country accounting standards. We document that a U.S. cross-listing is economically important, as U.S. ownership of a foreign firm roughly doubles upon cross-listing in the United States. We explore the cross-sectional variation in this "cross-listing effect" and find that the increase in U.S. investment is greatest for firms that are from weak accounting backgrounds and are otherwise informationally opaque, suggesting that the key effect of cross-listing is improvements in disclosure that are valued by U.S. investors. By contrast, cross-listing does not increase the appeal of stocks from countries with weak shareholder rights, suggesting that U.S. cross-listing cannot substitute for legal protections in the home country. Nor does the cross-listing effect appear to be driven simply by increased "familiarity"� with the stock or lowered cross-border transactions costs.

U.S. International Equity Investment

U.S. investors are the largest group of international equity investors in the world, but to date conclusive evidence on which types of foreign firms are able to attract U.S. investment is not available. Using a comprehensive dataset of all U.S. investment in foreign equities, we find that the single most important determinant of the amount of U.S. investment a foreign firm receives is whether the firm cross-lists on a U.S. exchange. Correcting for selection biases, cross-listing leads to a doubling (or more) in U.S. investment, an impact greater than all other factors combined. We also show that our firm-level analysis has implications for country-level studies, suggesting that research investigating equity investment patterns at the country-level should include cross-listing as an endogenous control variable. We describe easy-to-implement methods for including the importance of cross-listing at the country level.

Why Do Firms Use Insurance to Fund Worker Health Benefits? The Role of Corporate Finance

When a firm offers health benefits to workers, it exposes the firm to the risk of making payments when workers get sick. A firm can either pay health expenses out of its general assets, keeping the risk inside the firm, or it can purchase insurance, shifting the risk outside the firm. We analyze the firm’s decision to manage this risk. Using data on the insurance decisions of publicly-traded firms, we find that smaller firms, firms with more investment opportunities, and firms that face a convex tax schedule are more likely to hedge the risk of health benefit payments. Health risk is common to all firms, making this application an important contribution to understanding firms’ hedging decisions. Additionally, we reveal new and important determinants of the hedging decision relative to regulatory regimes. We also show that hedging health risk mitigates investment-cash flow sensitivities

Why Do Firms Use Insurance to Fund Worker Health Benefits? The Role of Corporate Finance

When a firm offers health benefits to workers, it exposes the firm to the risk of making payments when workers get sick. A firm can either pay health expenses out of its general assets, keeping the risk inside the firm, or it can purchase insurance, shifting the risk outside the firm. We analyze the firm’s decision to manage this risk. Using data on the insurance decisions of publicly-traded firms, we find that smaller firms, firms with more investment opportunities, and firms that face a convex tax schedule are more likely to hedge the risk of health benefit payments. Health risk is common to all firms, making this application an important contribution to understanding firms’ hedging decisions. Additionally, we reveal new and important determinants of the hedging decision relative to regulatory regimes. We also show that hedging health risk mitigates investment-cash flow sensitivities

Imaging the Beating Heart with Macroscopic Phase Stamping

We present a novel approach for imaging the beating embryonic heart, based on combining two independent imaging channels to capture the full spatio-temporal information of the moving 3D structure. High-resolution, optically-sectioned image recording is accompanied by simultaneous acquisition of low-resolution, whole-heart recording, allowing the latter to be used in post-acquisition processing to determine the macroscopic spatio-temporal phase of the heart beating cycle. Once determined, or 'stamped', the phase information common to both imaging channels is used to reconstruct the 3D beating heart. We demonstrated our approach in imaging the beating heart of the zebrafish embryo, capturing the entire heart over its full beating cycle, and characterizing cellular dynamic behavior with sub-cellular resolution

De Broglie Wavelength of a Nonlocal Four-Photon

Superposition is one of the most distinct features of quantum theory and has been demonstrated in numerous realizations of Young's classical double-slit interference experiment and its analogues. However, quantum entanglement - a significant coherent superposition in multiparticle systems - yields phenomena that are much richer and more interesting than anything that can be seen in a one-particle system. Among them, one important type of multi-particle experiments uses path-entangled number-states, which exhibit pure higher-order interference and allow novel applications in metrology and imaging such as quantum interferometry and spectroscopy with phase sensitivity at the Heisenberg limit or quantum lithography beyond the classical diffraction limit. Up to now, in optical implementations of such schemes lower-order interference effects would always decrease the overall performance at higher particle numbers. They have thus been limited to two photons. We overcome this limitation and demonstrate a linear-optics-based four-photon interferometer. Observation of a four-particle mode-entangled state is confirmed by interference fringes with a periodicity of one quarter of the single-photon wavelength. This scheme can readily be extended to arbitrary photon numbers and thus represents an important step towards realizable applications with entanglement-enhanced performance.Comment: 19 pages, 4 figures, submitted on November 18, 200

The Contribution of Halos with Different Mass Ratios to the Overall Growth of Cluster-Sized Halos

We provide a new observational test for a key prediction of the \Lambda CDM cosmological model: the contributions of mergers with different halo-to-main-cluster mass ratios to cluster-sized halo growth. We perform this test by dynamically analyzing seven galaxy clusters, spanning the redshift range $0.13 < z_c < 0.45$ and caustic mass range $0.4-1.5$ $10^{15} h_{0.73}^{-1}$ M$_{\odot}$, with an average of 293 spectroscopically-confirmed bound galaxies to each cluster. The large radial coverage (a few virial radii), which covers the whole infall region, with a high number of spectroscopically identified galaxies enables this new study. For each cluster, we identify bound galaxies. Out of these galaxies, we identify infalling and accreted halos and estimate their masses and their dynamical states. Using the estimated masses, we derive the contribution of different mass ratios to cluster-sized halo growth. For mass ratios between ~0.2 and ~0.7, we find a ~1 $\sigma$ agreement with \Lambda CDM expectations based on the Millennium simulations I and II. At low mass ratios, $\lesssim 0.2$, our derived contribution is underestimated since the detection efficiency decreases at low masses, $\sim 2 \times 10^{14}$ $h_{0.73}^{-1}$ M$_{\odot}$. At large mass ratios, $\gtrsim 0.7$, we do not detect halos probably because our sample, which was chosen to be quite X-ray relaxed, is biased against large mass ratios. Therefore, at large mass ratios, the derived contribution is also underestimated.Comment: 25 pages, 16 figures, 6 tables, 2 machine readable tables, accepted for publication in ApJ, updated acknowledgements and data table format modifications mad

PROPHETIC: Prospective Identification of Pneumonia in Hospitalized Patients in the Intensive Care Unit

BACKGROUND: Pneumonia is the leading infection-related cause of death. Using simple clinical criteria and contemporary epidemiology to identify patients at high risk of nosocomial pneumonia should enhance prevention efforts and facilitate development of new treatments in clinical trials. RESEARCH QUESTION: What are the clinical criteria and contemporary epidemiology trends helpful in identifying patients at high risk of nosocomial pneumonia? STUDY DESIGN AND METHODS: Within the intensive care units of 28 United States hospitals, we conducted a prospective cohort study among adults hospitalized more than 48 hours and considered high risk for pneumonia (defined as treatment with invasive or noninvasive ventilatory support or high levels of supplemental oxygen). We estimated the proportion of high-risk patients developing nosocomial pneumonia. Using multivariable logistic regression, we identified patient characteristics and treatment exposures associated with increased risk of pneumonia development during the intensive care unit admission. RESULTS: Between February 6, 2016 and October 7, 2016, 4613 high-risk patients were enrolled. Among 1464/4613 (32%) high-risk patients treated for possible nosocomial pneumonia, 537/1464 (37%) met the study pneumonia definition. Among high-risk patients, a multivariable logistic model was developed to identify key patient characteristics and treatment exposures associated with increased risk of nosocomial pneumonia development (c-statistic 0.709, 95% confidence interval 0.686 to 0.731). Key factors associated with increased odds of nosocomial pneumonia included an admission diagnosis of trauma or cerebrovascular accident, receipt of enteral nutrition, documented aspiration risk, and receipt of systemic antibacterials within the preceding 90 days. INTERPRETATION: Treatment for nosocomial pneumonia is common among intensive care unit patients receiving high levels of respiratory support, yet more than half of patients treated do not fulfill standard diagnostic criteria for pneumonia. Application of simple clinical criteria may improve the feasibility of clinical trials of pneumonia prevention and treatment by facilitating prospective identification of patients at highest risk