Boston College

About: Boston College is a education organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 9749 authors who have published 25406 publications receiving 1105145 citations. The organization is also known as: BC.

Risk management, capital structure and lending at banks

Abstract: We test how active management of bank credit risk exposure through the loan sales market affects capital structure, lending, profits, and risk. We find that banks that rebalance their loan portfolio exposures by both buying and selling loans – that is, banks that use the loan sales market for risk management purposes rather than to alter their holdings of loans – hold less capital than other banks; they also make more risky loans (loans to businesses) as a percentage of total assets than other banks. Holding size, leverage and lending activities constant, banks active in the loan sales market have lower risk and higher profits than other banks. Our results suggest that banks that improve their ability to manage credit risk may operate with greater leverage and may lend more of their assets to risky borrowers. Thus, the benefits of advances in risk management in banking may be greater credit availability, rather than reduced risk in the banking system.

Orientations to Video Games Among Gender and Age Groups

Abstract: Questionnaires were completed by 5th-, 8th-, and 11th-grade public schools students in rural and suburban school districts and by undergraduates at two universities in the United States (n = 1,242). They were asked about their orientation to video games—the amount of time they played, their motives for doing so, and the game types they preferred—to better understand the context in which effects research might be organized. The conceptual schema for this research was the uses-and-gratifications perspective. The males in the sample played video games at twice the weekly average of the females, were consistently stronger in all measured motives than the females, and preferred physically oriented video games over the females’ preference for more traditional, thoughtful games. Younger players opted for the fantasy motive in their playing and older players more so for competition. Preference for physical games declined among the older males, and generally motives were stronger in the middle years of playing for both males and females than in the youngest and oldest age groups. Regression analyses explained considerably more variance in game playing for males than for females.

Highly Sensitive Detection of Polarized Light Using Anisotropic 2D ReS2

Abstract: Due to the novel optical and optoelectronic properties, 2D materials have received increasing interests for optoelectronics applications. Discovering new properties and functionalities of 2D materials is challenging yet promising. Here broadband polarization sensitive photodetectors based on few layer ReS2 are demonstrated. The transistor based on few layer ReS2 shows an n-type behavior with the mobility of about 40 cm2 V−1 s−1 and on/off ratio of 105. The polarization dependence of photoresponse is ascribed to the unique anisotropic in-plane crystal structure, consistent with the optical absorption anisotropy. The linear dichroic photodetection with a high photoresponsivity reported here demonstrates a route to exploit the intrinsic anisotropy of 2D materials and the possibility to open up new ways for the applications of 2D materials for light polarization detection.

Heavy doping and band engineering by potassium to improve the thermoelectric figure of merit in p-type PbTe, PbSe, and PbTe(1-y)Se(y).

Abstract: We present detailed studies of potassium doping in PbTe1–ySey (y = 0, 0.15, 0.25, 0.75, 0.85, 0.95, and 1). It was found that Se increases the doping concentration of K in PbTe as a result of the balance of electronegativity and also lowers the lattice thermal conductivity because of the increased number of point defects. Tuning the composition and carrier concentration to increase the density of states around the Fermi level results in higher Seebeck coefficients for the two valence bands of PbTe1–ySey. Peak thermoelectric figure of merit (ZT) values of ∼1.6 and ∼1.7 were obtained for Te-rich K0.02Pb0.98Te0.75Se0.25 at 773 K and Se-rich K0.02Pb0.98Te0.15Se0.85 at 873 K, respectively. However, the average ZT was higher in Te-rich compositions than in Se-rich compositions, with the best found in K0.02Pb0.98Te0.75Se0.25. Such a result is due to the improved electron transport afforded by heavy K doping with the assistance of Se.

Intrinsic phonon relaxation times from first-principles studies of the thermal conductivities of Si and Ge

Abstract: Using a first-principles approach, we present forms for the intrinsic phonon relaxation times in semiconductors, which properly reflect the physically distinct behaviors of the normal and umklapp scattering processes. We find that accurate representation of the phonon-phonon scattering strength and inclusion of scattering of acoustic phonons by optic phonons are essential ingredients, which are missing from the decades old derivations of commonly used intrinsic relaxation times. We also assess the validity of the relaxation time approximation itself for silicon and germanium.