Steering effects on growth instability during step-flow growth of Cu on Cu(1,1,17)

Kinetic Monte Carlo simulation in conjunction with molecular dynamics simulation is utilized to study the effect of the steered deposition on the growth of Cu on Cu(1,1,17). It is found that the deposition flux becomes inhomogeneous in step train direction and the inhomogeneity depends on the deposition angle, when the deposition is made along that direction. Steering effect is found to always increase the growth instability, with respect to the case of homogeneous deposition. Further, the growth instability depends on the deposition angle and direction, showing minimum at a certain deposition angle off-normal to (001) terrace, and shows a strong correlation with the inhomogeneous deposition flux. The increase of the growth instability is ascribed to the strengthened step Erlich Schwoebel barrier effects that is caused by the enhanced deposition flux near descending step edge due to the steering effect.Comment: 5 page

Organizational attributes and the distribution of rewards in a region: managerial firms vs. knowledge clusters

This paper expands the organization theory and evidence on regional industrial agglomerations. We define regional economic activities according to the attributes of the organizations that populate a region and investigate how organizational characteristics influence macro-outcomes at a regional economic level. We focus on two dimensions emerging from two widely known organizational forms: the managerial corporation and the knowledge cluster with a marked orientation toward interfirm knowledge spillovers. We use an original data set of 146 U.S. cities to obtain variations in the extent to which they are populated by managerial firms or knowledge clusters. By utilizing city-level measures of managerial salaries, we test how the intensity of managerial corporation versus knowledge cluster characteristics affects the mean and dispersion of the "rewards" of cities. Our evidence suggests that higher managerial corporate characteristics lower the variability of rewards, while they have no effect on the mean of rewards. Higher-knowledge cluster characteristics produce both higher dispersion and higher expected rewards. We explain these results by looking at the different learning mechanisms of the two organizational types. In so doing, we highlight the role of intra- and interfirm knowledge processes as important sources of differences in the rewards of the two models. From an empirical point of view, results are confirmed using both patent-based and skill mobility-based measures of knowledge spillovers.Publicad

Quadratic integrals of motions for the systems of identical particles-quantum case

The quantum dynamical systems of identical particles admitting an additional integral quadratic in momenta are considered. It is found that an appropriate ordering procedure exists which allows to convert the classical integrals into their quantum counterparts. The relation to the separation of variables in Schroedinger equation is discussed.Comment: 6 pages, no figure

Element-resolved x-ray ferrimagnetic and ferromagnetic resonance spectroscopy

We report on the measurement of element-specific magnetic resonance spectra at gigahertz frequencies using x-ray magnetic circular dichroism (XMCD). We investigate the ferrimagnetic precession of Gd and Fe ions in Gd-substituted Yttrium Iron Garnet, showing that the resonant field and linewidth of Gd precisely coincide with Fe up to the nonlinear regime of parametric excitations. The opposite sign of the Gd x-ray magnetic resonance signal with respect to Fe is consistent with dynamic antiferromagnetic alignment of the two ionic species. Further, we investigate a bilayer metal film, Ni$_{80}$Fe$_{20}$(5 nm)/Ni(50 nm), where the coupled resonance modes of Ni and Ni$_{80}$Fe$_{20}$ are separately resolved, revealing shifts in the resonance fields of individual layers but no mutual driving effects. Energy-dependent dynamic XMCD measurements are introduced, combining x-ray absorption and magnetic resonance spectroscopies.Comment: 16 pages, 8 figure

Profiting from enabling technologies?

How to profit from innovation has been an important question for both innovation scholars and practitioners over the years. It is certainly a relevant question for all types of technological innovation, including emerging ones. Teece's (1986) profiting from innovation (PFI) framework sets forth a theory of the relevant contingencies. However, Teece's framework focuses on technologies with applications in specific domains. We focus on the question of how to profit from enabling technologies: technologies that are applicable across multiple domains. We argue that capturing value in such circumstances is fundamentally different from profiting from less-enabling technologies and raises new issues with respect to the relevant business models and public policies. This paper's contribution is threefold. It formally revises and extends the original PFI framework to include the case of enabling technologies; it provides empirical evidence to support the distinction between profiting from enabling as compared to profiting from narrower "discrete" technologies; and it generates perspectives on the appropriate business models for these technologies and discusses related public-policy implications, in light of the fact that the share of the benefits the innovator can capture is likely to be even smaller for enabling than for discrete technologies

Functional Role of miR-155 in the Pathogenesis of Diabetes Mellitus and Its Complications

Substantial evidence indicates that microRNA-155 (miR-155) plays a crucial role in the pathogenesis of diabetes mellitus (DM) and its complications. A number of clinical studies reported low serum levels of miR-155 in patients with type 2 diabetes (T2D). Preclinical studies revealed that miR-155 partakes in the phenotypic switch of cells within the islets of Langerhans under metabolic stress. Moreover, miR-155 was shown to regulate insulin sensitivity in liver, adipose tissue, and skeletal muscle. Dysregulation of miR-155 expression was also shown to predict the development of nephropathy, neuropathy, and retinopathy in DM. Here, we systematically describe the reports investigating the role of miR-155 in DM and its complications. We also discuss the recent results from in vivo and in vitro models of type 1 diabetes (T1D) and T2D, discussing the differences between clinical and preclinical studies and shedding light on the molecular pathways mediated by miR-155 in different tissues affected by DM