Explaining the diversification discount

Diversified firms trade at a discount relative to similar single-segment firms. We argue in this paper that this observed discount is not per se evidence that diversification destroys value. Firms choose to diversify. Firm characteristics, which make firms diversify might also cause them to be discounted. Not taking into account these firm characteristics might wrongly attribute the observed discount to diversification. Data from the Compustat Industry Segment File from 1978 to 1996 are used to select a sample of single segment and diversifying firms. We use three alternative econometric techniques to control for the endogeneity of the diversification decision. All three methods suggest the presence of self-selection in the decision to diversify and a negative correlation between firm's choice to diversify and firm value. The diversification discount always drops, and sometimes turns into a premium, when we control for the endogeneity of the diversification decision. We do a similar analysis in a sample of refocusing firms. Again, some evidence of self-selection by firms exists and we now find a positive correlation between firm's choice to refocus and firm value. These results consistently suggest the importance of taking the endogeneity of the diversification status into account, in analyzing its effects on firm value.Diversification discount;

Tying knots in light fields

We construct a new family of null solutions to Maxwell's equations in free space whose field lines encode all torus knots and links. The evolution of these null fields, analogous to a compressible flow along the Poynting vector that is both geodesic and shear-free, preserves the topology of the knots and links. Our approach combines the Bateman and spinor formalisms for the construction of null fields with complex polynomials on $\mathbb{S}^3$. We examine and illustrate the geometry and evolution of the solutions, making manifest the structure of nested knotted tori filled by the field lines.Comment: 5 pages, 3 figure

Transition of Chaotic Flow in a Radially Heated Taylor-Couette System

Numerical simulations have been performed to study the stability of heated, incompressible Taylor-Couette flow for a radius ratio of 0.7 and a Prandtl number of 0.7. As Gr is increased, the Taylor cell that has the same direction of circulation as the natural convection current increases in size and the counterrotating cell becomes smaller. The flow remains axisymmetric and the average heat transfer decreases with the increase in Gr. When the cylinder is impulsively heated, the counterrotating cell vanishes and n = 1 spiral is formed for Gr = 1000. This transition marks an increase in the heat transfer due to an increase in the radial velocity component of the fluid. By slowly varying the Grashof number, the simulations demonstrate the existence of a hysteresis loop. Two different stable states with same heat transfer are found to exist at the same Grashof number. A time-delay analysis of the radial velocity and the local heat transfer coefficient time is performed to determine the dimension at two Grashof numbers. For a fixed Reynolds number of 100, the two-dimensional projection of the reconstructed attractor shows a limit cycle for Gr = −1700. The limit cycle behavior disappears at Gr = −2100, and the reconstructed attractor becomes irregular. The attractor dimension increases to about 3.2 from a value of 1 for the limit cycle case; similar values were determined for both the local heat transfer and the local radial velocity, indicating that the dynamics of the temperature variations can be inferred from that of the velocity variations

Numerical Simulations of Heat Transfer in Taylor-Couette Flow

Numerical simulations have been performed to study the effects of the gravitational and the centrifugal potentials on the stability of heated, incompressible Taylor-Couette flow. The flow is confined between two differentially heated, concentric cylinders, and the inner cylinder is allowed to rotate. The Navier-Stokes equations and the coupled energy equation are solved using a spectral method. To validate the code, comparisons are made with existing linear stability analysis and with experiments. The code is used to calculate the local and average heat transfer coefficients for a fixed Reynolds number (Re = 100) and a range of Grashof numbers. The investigation is primarily restricted to radius ratios 0.5 and 0.7 for fluids with Prandtl number of about 0.7. The variation of the local coefficients of heat transfer on the cylinder surface is investigated, and maps showing different stable states of the flow are presented. Results are also presented in terms of the equivalent conductivity, and show that heat transfer decreases with Grashof number in axisymmetric Taylor vortex flow regime, and increases with Grashof number after the flow becomes nonaxisymmetric

Glucose directs amyloid-beta into membrane-active oligomers

Oligomeric amyloid-β 1-42 (Aβ-42) peptides are considered to be the most toxic species connected to the occurrence of Alzheimer's disease. However, not all aggregation conditions promote oligomer formation in vitro, raising the question whether oligomer formation in vivo also requires a specific suitable cellular environment. We recently found that interaction with neuronal membranes initiates aggregation of Aβ-42 and neuronal uptake. Our data suggest that small molecules in the extracellular space can facilitate the formation of membrane-active Aβ-42 oligomers. We analyzed the early stage of Aβ-42 aggregation in the presence of glucose and sucrose and found that these sugars strongly favor Aβ-42 oligomer formation. We characterized oligomers by dynamic light scattering, atomic force microscopy, immuno-transmission electron microscopy and fluorescence cross correlation spectroscopy. We found that Aβ-42 spontaneously and rapidly forms low molecular weight oligomers in the presence of sugars. Slightly acidic pH (6.7-7) greatly favors oligomer formation when compared to the extracellular physiological pH (7.4). Circular dichroism demonstrated that these Aβ-42 oligomers did not adopt a β-sheet structure. Unstructured oligomeric Aβ-42 interacted with membrane bilayers of giant unilamellar vesicles (GUV) and neuronal model cells, facilitated cellular uptake of Aβ-42, and inhibition of mitochondrial activity. Our data therefore suggest that elevated concentrations of glucose within the range observed in diabetic individuals (10 mM) facilitate the formation of membrane-active Aβ-42 oligomers

CoMeT: An Integrated Interval Thermal Simulation Toolchain for 2D, 2.5 D, and 3D Processor-Memory Systems

Processing cores and the accompanying main memory working in tandem enable the modern processors. Dissipating heat produced from computation, memory access remains a significant problem for processors. Therefore, processor thermal management continues to be an active research topic. Most thermal management research takes place using simulations, given the challenges of measuring temperature in real processors. Since core and memory are fabricated on separate packages in most existing processors, with the memory having lower power densities, thermal management research in processors has primarily focused on the cores. Memory bandwidth limitations associated with 2D processors lead to high-density 2.5D and 3D packaging technology. 2.5D packaging places cores and memory on the same package. 3D packaging technology takes it further by stacking layers of memory on the top of cores themselves. Such packagings significantly increase the power density, making processors prone to heating. Therefore, mitigating thermal issues in high-density processors (packaged with stacked memory) becomes an even more pressing problem. However, given the lack of thermal modeling for memories in existing interval thermal simulation toolchains, they are unsuitable for studying thermal management for high-density processors. To address this issue, we present CoMeT, the first integrated Core and Memory interval Thermal simulation toolchain. CoMeT comprehensively supports thermal simulation of high- and low-density processors corresponding to four different core-memory configurations - off-chip DDR memory, off-chip 3D memory, 2.5D, and 3D. CoMeT supports several novel features that facilitate overlying system research. Compared to an equivalent state-of-the-art core-only toolchain, CoMeT adds only a ~5% simulation-time overhead. The source code of CoMeT has been made open for public use under the MIT license.Comment: https://github.com/marg-tools/CoMe

Creative Approaches to the Creation of Contemporary Art Objects and Features of their Legal Protection

This study is devoted to the analysis of the current state of legislation of Ukraine and EU countries on copyright protection of works with an unstable form of expression, as well as to determine the features of the legal protection of such objects. The purpose of the article was to explore the existing possibilities in the law of Ukraine and the law of the EU countries for the protection of works with an unstable form of their expression. The article, based on the analysis of international legal acts and national legislation, highlights the elements of protection of works. A significant place in work is devoted to the analysis of theoretical, legislative approaches to the definition of "creativity", "originality", "novelty". It is stated that there is no single waste to the definition of these concepts in the literature and not regulated in the legislation in the field of copyright. A comparative legal analysis of the case-law of the United Kingdom and the United States on the provision of legal protection to works with an unstable form. It is concluded that the normative definition of “creative work”, which is associated exclusively with works of cultural value, is not acceptable for copyright. The article analyses the judicial practice of Ukraine, which has developed in the definition of creative work and illustrates its ambiguity. It is concluded that judges, considering such cases, try to find some stable elements that are inherent in works with an unstable form of expression. Keywords: Intellectual property law, object of intellectual property law, subjects of intellectual property law

Proprietary Milk Protein Concentrate Reduces Joint Discomfort While Improving Exercise Performance in Non-Osteoarthritic Individuals

Milk and dairy products are known to contain various bioactives with potential anti-inflammatory and immune modulating effects. Previous research has indicated that milk produced from hyperimmunized cows provided meaningful health benefits to individuals suffering from varying degrees of osteoarthritis and rheumatoid arthritis. PURPOSE: To examine the impact of a proprietary milk protein concentrate on joint discomfort and physical function, exercise performance, quality of life and various measures of affect. METHODS: Non-osteoarthritic men (42.5 ± 8.9 years, 176.7 ± 6.7 cm, 89.9 ± 11.5 kg, 28.8 ± 3.5 kg/m2, n = 30) and women (46.4 ± 9.6 years, 163.1 ± 8.2 cm, 72.2 ± 13.1 kg, 27.2 ± 5.3 kg/m2, n = 28) with mild to moderate knee pain during physical activity were randomized in a double-blind, placebo-controlled fashion to consume daily either a placebo (PLA) or a proprietary milk protein concentrate (MP) for a period of 8 weeks. Participants completed a functional capacity test pre and post-supplementation and completed visual analog scales (VAS), a 6-min walking test, WOMAC and profile of mood states (POMS) to assess changes in joint health, discomfort, physical function, exercise performance and affect. Mixed factorial ANOVA was used for all statistical analysis and significance was set a priori at p ≤ 0.05. RESULTS: Distance covered in the 6-min walking significantly improved 9% in MP versus 2% in PLA (mean difference: 110 ± 43 m, p = 0.012) in addition to 11 WOMAC components and 5 VAS reflective of MP improving joint health, discomfort and joint stability (all p \u3c 0.05 vs. PLA). Additionally, MP also improved overall perceptions of neck and back health compared to PLA. Serum and whole blood indicators of clinical safety remained within normal ranges throughout the study. CONCLUSIONS: In comparison to placebo, daily doses of proprietary milk protein concentrate yielded improvements in several components of the WOMAC, multiple visual analog scales indicative of joint health and stability, discomfort and pain, as well as significant improvements in distance covered during a 6-min walking test. Supplementation was well tolerated with no significant changes in whole-blood or serum markers of clinical safety