Ge growth on ion-irradiated Si self-affine fractal surfaces

We have carried out scanning tunneling microscopy experiments under ultrahigh vacuum condition to study the morphology of ultrathin Ge films eposited on pristine Si(100) and ion-irradiated Si(100) self-affine fractal surfaces. The pristine and the ion-irradiated Si(100) surface have roughness exponents of alpha=0.19+/-0.05 and alpha=0.82+/-0.04 respectively. These measurements were carried out on two halves of the same sample where only one half was ion-irradiated. Following deposition of a thin film of Ge (~6 A) the roughness exponents change to 0.11+/-0.04 and 0.99+/-0.06, respectively. Upon Ge deposition, while the roughness increases by more than an order of magnitude on the pristine surface, a smoothing is observed for the ion-irradiated surface. For the ion-irradiated surface the correlation length xi increases from 32 nm to 137 nm upon Ge deposition. Ge grows on Si surfaces in the Stranski-Krastanov or layer-plus-island mode where islands grow on a wetting layer of about three atomic layers. On the pristine surface the islands are predominantly of square or rectangular shape, while on the ion-irradiated surface the islands are nearly diamond shaped. Changes of adsorption behaviour of deposited atoms depending on the roughness exponent (or the fractal dimension) of the substrate surface are discussed.Comment: 5 pages, 2 figures and 1 tabl

Global vs. regional approaches to the internationalisation process of Nigerian banks: some preliminary evidences

Research investigating internationalisation process of service firms from developing countries is limited. This paper draws on extant work on internationalisation of the firm, services’ internationalisation and proposes conceptual framework that investigates the internationalisation process of three leading Nigerian banks namely; Zenith Bank Nigeria (ZBN)Plc, First Bank of Nigeria (FBN) Plc and Intercontinental Bank Plc. This work attempts to evaluate the internationalisation process of these financial service firms to the UK market. It seeks to understand the driving forces behind these banks’ motives for internationalisation to UK; the various influences that might have affected their decisions, the several internationalisation routes and strategies they might have followed in doing so; and the next strategies they might adopt in furthering their internationalisation process. This work contributes to some understanding of the reasons why service firms from developing countries internationalising to advanced locations like the UK. The analyses and findings of this study offer unique insights into the internationalisation processes of the three case banks, and examines how their different pathways was determined by a balancing act of leveraging accumulated global and regional strengths to achieved sustained international growth

Path Dependence, VRIN Resource Endowments, and Managers: Towards an Integration of Resource-Based Theory and Upper Echelons Theory

Path dependencies associated with the firm’s evolving resource endowments lead to redundancies, which makes it sub-optimal to attain sustainable competitive advantage based on these resource bundles. In this context, managers can play a proactive role by ensuring that resource endowments continue to remain beneficial for their organizations. By suggesting such a linkage and the enabling role of managers, I provide a way to integrate core arguments of two of the foremost organizationaltheories in vogue: resource-based theory (RBT) and upper echelons theory (UET)

A Reaction Diffusion Model Of Pattern Formation In Clustering Of Adatoms On Silicon Surfaces

We study a reaction diffusion model which describes the formation of patterns on surfaces having defects. Through this model, the primary goal is to study the growth process of Ge on Si surface. We consider a two species reaction diffusion process where the reacting species are assumed to diffuse on the two dimensional surface with first order interconversion reaction occuring at various defect sites which we call reaction centers. Two models of defects, namely a ring defect and a point defect are considered separately. As reaction centers are assumed to be strongly localized in space, the proposed reaction-diffusion model is found to be exactly solvable. We use Green's function method to study the dynamics of reaction diffusion processes. Further we explore this model through Monte Carlo (MC) simulations to study the growth processes in the presence of a large number of defects. The first passage time statistics has been studied numerically. Copyright 2012 Author(s). This article is distributed under a Creative Commons Attribution 3.0 Unported License. [http://dx.doi.org/10.1063/1.4757592]Microelectronics Research Cente

Inquiring into Entrepreneurial Orientation: Making Progress, One Step at a Time

As we think through the four papers that comprise this special issue, we cannot help but be elated at the progress made by entrepreneurial orientation (EO) scholarship over the past few decades. Indeed, it seems safe to contend that EO defies the description of entrepreneurship research as a “hodgepodge” (Shane & Venkataraman, 2000), and instead serves as a good example of how a cumulative body of knowledge should develop in organizational science

Targeting S1P receptors in experimental autoimmune encephalomyelitis in mice improves early deficits in locomotor activity and increases ultrasonic vocalisations

Fingolimod (FTY720) is an oral therapy for relapsing remitting multiple sclerosis (MS) and targets sphingosine 1-phosphate receptors (S1PRs). FTY720 also rescues animals from experimental autoimmune encephalomyelitis (EAE), an animal model of MS. The protective effects of FTY720 in EAE are primarily scored manually by examining weight loss and limb paralysis that begins around 10-12 days after immunisation. To our knowledge, pre-clinical effects of FTY720 on animal behaviour early in EAE have not been explored. Here, we developed an automated behaviour monitoring system to examine the early effects of FTY720 on subtle pre-symptomatic behaviour of mice induced with EAE. Our automated home-cage monitoring system (AHC-MS) enabled non-contact detection of movement and ultrasonic vocalisations (USVs) of mice induced with EAE, thus allowing detection of subtle changes in mouse behaviour before paralysis occurs. Mice receiving FTY720 emit longer USVs and display higher levels of motor activity than vehicle-treated EAE mice before clinical symptoms become apparent. Importantly, this study promotes the 3Rs ethics (replacement, reduction and refinement) in the EAE animal model and may also improve pre-screening of potentially novel MS therapies. In addition, this is the first report showing the early effects of FTY720 in EAE which underscores its protective effects

The Impact of Medical Students' Metacognitive Awareness Level on Their Academic Performance

Background: Metacognition influences the academic performance of medical students. The objective of our study was to determine the metacognitive awareness level of medical students in different academic groups in physiology course and develop a guideline on that basis to provide academic support.Methods: A 52-items metacognitive awareness inventory (MAI) devised by Schraw and Dennison was used to assess the metacognition level of low (85%) students in a physiology course at Trinity Medical Sciences University (TMSU).Results: Sixty-four students participated in the study. A significant positive correlation (rs=0.462) was found between the total MAI score and the final score in the physiology course. High performing students reported significantly higher score on declarative knowledge (p=0.001); procedural knowledge (p=0.048); implementation of strategies (p=0.003); correction (p=0.000) and evaluation of effectiveness (p=0.000) subscale than their low performing counterparts. Compared to average performing students, high performers were found significantly superior in terms of declarative knowledge (p=0.006), better planning (p=0.047), monitoring (p=0.008) and evaluation of effectiveness (0.004) of the learning process.Conclusions: Metacognitive awareness level has a significant impact on the academic performance of medical students in the physiology course. Low performers need to improve both declarative and procedural knowledge while average performers should augment their declarative knowledge. In terms of regulation of cognition, low performers should develop better implementation, correction, and evaluation skills while average performers should make better planning other than improving their monitoring and evaluating skills