1,747 research outputs found
Discontinuity in the Environment, Firm Response and Dynamic Capabilities
This paper identifies and focuses on a specific type of environmental development called discontinuity. Discontinuities in the forms of rapid technological innovations, regulatory reforms, institutional overhauls, and socio-cultural developments are the source of opportunities and threats to the firm. Firm responds to these discontinuities in specific ways in sustaining its existence at different points of time. This paper conceptualizes discontinuity and identifies its natures; explores the possible types of responses by the firm, and their enablers. The capability of sensing, seizing and re-shaping are captured to establish the linkages in the framework of interrelations. It posits a set of propositions based on conceptual development and illustration of two cases.
Ground states and excited states of hypernuclei in Relativistic Mean Field approach
Hypernuclei have been studied within the framework of Relativistic Mean Field
theory. The force FSU Gold has been extended to include hyperons. The effective
hyperon-nucleon and nucleon-nucleon interactions have been obtained by fitting
experimental energies in a number of hypernuclei over a wide range of mass.
Calculations successfully describe various features including hyperon
separation energy and single particle spectra of single-\Lambda hypernuclei
throughout the periodic table. We also extend this formalism to double-\Lambda
hypernuclei.Comment: 16 pages,3 figure
Direct numerical simulation of a warm cloud top model interface: Impact of the transient mixing on different droplet population
Turbulent mixing through atmospheric cloud and clear air interface plays an important role in the life of a cloud. Entrainment and detrainment of clear air and cloudy volume result in mixing across the interface, which broadens the cloud droplet spectrum. In this study, we simulate the transient evolution of a turbulent cloud top interface with three initial mono-disperse cloud droplet population, using a pseudo-spectral Direct Numerical Simulation (DNS) along with Lagrangian droplet equations, including collision and coalescence. Transient evolution of in-cloud turbulent kinetic energy (TKE), density of water vapour and temperature is carried out as an initial value problem exhibiting transient decay. Mixing in between the clear air and cloudy volume produced turbulent fluctuations in the density of water vapour and temperature, resulting in supersaturation fluctuations. Small scale turbulence, local supersaturation conditions and gravitational forces have different weights on the droplet population depending on their sizes. Larger droplet populations, with initial 25 and 18 μm radii, show significant growth by droplet-droplet collision and a higher rate of gravitational sedimentation. However, the smaller droplets, with an initial 6 μm radius, did not show any collision but a large size distribution broadening due to differential condensation/evaporation induced by the mixing, without being influenced by gravity significantly
Tripartite degrons confer diversity and specificity on regulated protein degradation in the ubiquitin-proteasome system
Specific signals (degrons) regulate protein turnover mediated by the ubiquitin-proteasome system. Here we systematically analyse known degrons and propose a tripartite model comprising the following: (1) a primary degron (peptide motif) that specifies substrate recognition by cognate E3 ubiquitin ligases, (2) secondary site(s) comprising a single or multiple neighbouring ubiquitinated lysine(s) and (3) a structurally disordered segment that initiates substrate unfolding at the 26S proteasome. Primary degron sequences are conserved among orthologues and occur in structurally disordered regions that undergo E3-induced folding-on-binding. Posttranslational modifications can switch primary degrons into E3-binding-competent states, thereby integrating degradation with signalling pathways. Degradation-linked lysines tend to be located within disordered segments that also initiate substrate degradation by effective proteasomal engagement. Many characterized mutations and alternative isoforms with abrogated degron components are implicated in disease. These effects result from increased protein stability and interactome rewiring. The distributed nature of degrons ensures regulation, specificity and combinatorial control of degradation. © 2016 Nature America, Inc
Stability of strange stars (SS) derived from a realistic equation of state
A realistic equation of state (EOS) leads to realistic strange stars (ReSS)
which are compact in the mass radius plot, close to the Schwarzchild limiting
line (Dey et al 1998). Many of the observed stars fit in with this kind of
compactness, irrespective of whether they are X-ray pulsars, bursters or soft
repeaters or even radio pulsars. We point out that a change in the
radius of a star can be small or large, when its mass is increasing and this
depends on the position of a particular star on the mass radius curve. We carry
out a stability analysis against radial oscillations and compare with the EOS
of other strange star (SS) models. We find that the ReSS is stable and an M-R
region can be identified to that effect.Comment: 16 pages including 5 figures. Accepted for publication in MPL
The impact of urban road network morphology on pedestrian wayfinding behavior
During wayfinding pedestrians do not always choose the shortest available route. Instead, route choices are guided by several well-known wayfinding strategies or heuristics. These heuristics minimize cognitive effort and usually lead to satisfactory route choices. Our previous study evaluated the costs of four well-known pedestrian wayfinding heuristics and their variation across nine network morphologies. It was observed that the variation in the cost of these wayfinding heuristics increased with an increase in the irregularity of the network, indicating that people may opt for more diverse heuristics while walking through relatively regular networks, and may prefer specific heuristics in the relatively irregular ones. The study presented here aims to investigate this claim by comparing simulated routes with observed pedestrian trajectories in Beijing and Melbourne, two cities at opposite ends of the regularity spectrum. We found that the values of mean route length and mean Network Hausdorff Distance for walking trips made in Melbourne were consistently lesser than the corresponding values obtained in Beijing. Also, across both the cities, we found that while there was minimal variation in the popularity of heuristics overall, in cases where different heuristics produced dissimilar routes, the shortest leg first strategy and the least angle strategy were more popular
Estimation of carrier life time from intrinsic photoluminescence of ZnO
Comprehensive knowledge of the optical properties, particularly of the room
temperature (RT) photoluminescence (PL), of ZnO is essential for the future employment of this wideband
gap (~3.3 eV at 300 K) II-VI compound semiconductor in photonic and optoelectronic device
structures [1]. Hence, vigorous research activities on ZnO thin films, epilayers, and crystals took place
during the last two decades, encompassing a vast variety of effects and phenomena such as birefringence,
photocurrent, PL including sub-band gap emission, reflectance, transmittance, excitonic properties,
Raman modes, and absorption edge steepness [1-4]. However, despite that large body of knowledge and
its essential importance for light emitting processes, a discussion of the ZnO PL lineshape is not found
in the literature [5]
Intrinsic photoluminescence stokes shift in thin-film cadmium sulfide
Exciting a semiconductor through light absorption produces photoluminescence (PL).
In general, the emitted energy is lower than the energy absorbed. The phenomenon, first discovered
in the nineteenth century, is known as Stokes shift energy [1]. The change in energy (AS t o k e s), crucial
for the information about the phonon relaxation in the material and with importance in light emitting
devices, has not been investigated experimentally very systematically [2]. In this project, we present the
observation of the intrinsic photoluminescence Stokes shift in a semiconductor
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