The building of a new business ecosystem: Sustaining national competitive advantage through electronic commerce

Despite the high level of interest in the role of governments in building national information infrastructure (NII) as a source of competitive advantage, it is still not clear how major information technology initiatives can help leverage national economies into the global marketplace. In light of the recent rollout of one of the world's largest electronic commerce initiatives, we examine the role of private-public partnerships in the success of such initiative in Hong Kong. Furthermore, we trace the 3 stages of the project - development, implementation, and competitive entrenchment - to identify the difficulties and challenges encountered and how these were overcome. By drawing some comparisons with the Singapore approach, we identify the kind of government involvement appropriate to spur on national competitiveness. We show that in building the NII, the dual aspects of private-sector leadership and government involvement are mutually reinforcing. Government intervention is necessary in creating the initial supply push, whereas the demand pull engendered by the market is critical for leveraging the NII as a platform for national competitiveness. The ramification of the study for other countries is discussed.published_or_final_versio

Random iteration of analytic maps

We consider analytic maps Fj: D → D of a domain D into itself and ask when does the sequence f1 ο⋯ο fn converge locally uniformly on D to a constant. In the case of one complex variable, we are able to show that this is so if there is a sequence {w1, w2,...} in D whose values are not taken by any f j in D, and which is homogeneous in the sense that it comes within a fixed hyperbolic distance of any point of D. The situation for several complex variables is also discussed.published_or_final_versio

The use of sex hormones in women with rheumatological diseases

A number of rheumatological diseases predominantly affect women of reproductive age. There has always been concern that the use of oestrogen-containing agents such as combined hormonal contraception and hormone therapy might aggravate these conditions. This article reviews the up-to-date evidence regarding the safety of using these agents in women with various rheumatological diseases, with emphasis on systemic lupus erythematosus and rheumatoid arthritis. In the absence of antiphospholipid antibody or other prothrombotic risk factors, combined hormonal contraception is not contra-indicated in most rheumatological conditions including inactive systemic lupus erythematosus. Moreover, hormone therapy is generally not contra-indicated except for women with active systemic lupus erythematosus disease where its effect on disease flare is less clear and individual judgement is required.published_or_final_versio

Kondo physics in carbon nanotubes

The connection of electrical leads to wire-like molecules is a logical step in the development of molecular electronics, but also allows studies of fundamental physics. For example, metallic carbon nanotubes are quantum wires that have been found to act as one-dimensional quantum dots, Luttinger-liquids, proximity-induced superconductors and ballistic and diffusive one-dimensional metals. Here we report that electrically-contacted single-wall nanotubes can serve as powerful probes of Kondo physics, demonstrating the universality of the Kondo effect. Arising in the prototypical case from the interaction between a localized impurity magnetic moment and delocalized electrons in a metallic host, the Kondo effect has been used to explain enhanced low-temperature scattering from magnetic impurities in metals, and also occurs in transport through semiconductor quantum dots. The far higher tunability of dots (in our case, nanotubes) compared with atomic impurities renders new classes of Kondo-like effects accessible. Our nanotube devices differ from previous systems in which Kondo effects have been observed, in that they are one-dimensional quantum dots with three-dimensional metal (gold) reservoirs. This allows us to observe Kondo resonances for very large electron number (N) in the dot, and approaching the unitary limit (where the transmission reaches its maximum possible value). Moreover, we detect a previously unobserved Kondo effect, occurring for even values of N in a magnetic field.Comment: 7 pages, pdf onl

Modelling the nucleon wave function from soft and hard processes

Current light-cone wave functions for the nucleon are unsatisfactory since they are in conflict with the data of the nucleon's Dirac form factor at large momentum transfer. Therefore, we attempt a determination of a new wave function respecting theoretical ideas on its parameterization and satisfying the following constraints: It should provide a soft Feynman contribution to the proton's form factor in agreement with data; it should be consistent with current parameterizations of the valence quark distribution functions and lastly it should provide an acceptable value for the \jp \to N \bar N decay width. The latter process is calculated within the modified perturbative approach to hard exclusive reactions. A simultaneous fit to the three sets of data leads to a wave function whose $x$-dependent part, the distribution amplitude, shows the same type of asymmetry as those distribution amplitudes constrained by QCD sum rules. The asymmetry is however much more moderate as in those amplitudes. Our distribution amplitude resembles the asymptotic one in shape but the position of the maximum is somewhat shifted.Comment: 32 pages RevTex + PS-file with 5 figures in uu-encoded, compressed fil

Kondo Conductance in an Atomic Nanocontact from First Principles

The electrical conductance of atomic metal contacts represents a powerful tool to detect nanomagnetism. Conductance reflects magnetism through anomalies at zero bias -- generally with Fano lineshapes -- due to the Kondo screening of the magnetic impurity bridging the contact. A full atomic-level understanding of this nutshell many-body system is of the greatest importance, especially in view of our increasing need to control nanocurrents by means of magnetism. Disappointingly, zero bias conductance anomalies are not presently calculable from atomistic scratch. In this Letter we demonstrate a working route connecting approximately but quantitatively density functional theory (DFT) and numerical renormalization group (NRG) approaches and leading to a first-principles conductance calculation for a nanocontact, exemplified by a Ni impurity in a Au nanowire. A Fano-like conductance lineshape is obtained microscopically, and shown to be controlled by the impurity s-level position. We also find a relationship between conductance anomaly and geometry, and uncover the possibility of opposite antiferromagnetic and ferromagnetic Kondo screening -- the latter exhibiting a totally different and unexplored zero bias anomaly. The present matching method between DFT and NRG should permit the quantitative understanding and exploration of this larger variety of Kondo phenomena at more general magnetic nanocontacts.Comment: 11 pages, 3 figures. Supplementary materials under request at [email protected]

Comparison of Several Methods of Chromatographic Baseline Removal with a New Approach Based on Quantile Regression

The article is intended to introduce and discuss a new quantile regression method for baseline detrending of chromatographic signals. It is compared with current methods based on polynomial fitting, spline fitting, LOESS, and Whittaker smoother, each with thresholding and reweighting approach. For curve flexibility selection in existing algorithms, a new method based on skewness of the residuals is successfully applied. The computational efficiency of all approaches is also discussed. The newly introduced methods could be preferred to visible better performance and short computational time. The other algorithms behave in comparable way, and polynomial regression can be here preferred due to short computational time

Fitness consultations in routine care of patients with type 2 diabetes in general practice: an 18-month non-randomised intervention study

<p>Abstract</p> <p>Background</p> <p>Increasing physical activity is a cornerstone in the treatment of type 2 diabetes and in general practice it is a challenge to achieve long-term adherence to this life style change. The aim of this study was to investigate in a non-randomised design whether the introduction of motivational interviewing combined with fitness tests in the type 2 diabetes care programme was followed by a change in cardio-respiratory fitness expressed by VO_2max, muscle strength of upper and lower extremities, haemoglobin A_1c(HbA_1c) and HDL-cholesterol.</p> <p>Methods</p> <p>Uncontrolled 18-month intervention study with follow-up and effect assessment every 3 months in a primary care unit in Denmark with six general practitioners (GPs). Of 354 eligible patients with type 2 diabetes, 127 (35.9%) were included. Maximum work capacity was tested on a cycle ergometer and converted to VO_2max. Muscle strength was measured with an arm curl test and a chair stand test. The results were used in a subsequent motivational interview conducted by one of the GPs. Patients were encouraged to engage in lifestyle exercise and simple home-based self-managed exercise programmes. Data were analysed with mixed models.</p> <p>Results</p> <p>At end of study, 102 (80.3%) participants remained in the intervention. Over 18 months, VO_2maxincreased 2.5% (p = 0.032) while increases of 33.2% (p < 0.001) and 34.1% (p < 0.001) were registered for the arm curl test and chair stand test, respectively. HDL-cholesterol increased 8.6% (p < 0.001), but HbA_1cremained unchanged (p = 0.57) on a low level (6.8%). Patients without cardiovascular disease or pain from function limitation increased their VO_2maxby 5.2% (p < 0.0001) and 7.9% (p = 0.0008), respectively.</p> <p>Conclusions</p> <p>In this 18-month study, participants who had repeated fitness consultations, including physical testing and motivational interviewing to improve physical activity, improved VO_2max, muscle strength, and lipid profile. Our results indicate that physical testing combined with motivational interviewing is feasible in a primary health care setting. Here, a fitness consultation tailored to the individual patient, his/her comorbidities and conditions in the local area can be incorporated into the diabetes programme to improve patients' muscle strength and cardio-respiratory fitness.</p

Gain control network conditions in early sensory coding

Gain control is essential for the proper function of any sensory system. However, the precise mechanisms for achieving effective gain control in the brain are unknown. Based on our understanding of the existence and strength of connections in the insect olfactory system, we analyze the conditions that lead to controlled gain in a randomly connected network of excitatory and inhibitory neurons. We consider two scenarios for the variation of input into the system. In the first case, the intensity of the sensory input controls the input currents to a fixed proportion of neurons of the excitatory and inhibitory populations. In the second case, increasing intensity of the sensory stimulus will both, recruit an increasing number of neurons that receive input and change the input current that they receive. Using a mean field approximation for the network activity we derive relationships between the parameters of the network that ensure that the overall level of activity of the excitatory population remains unchanged for increasing intensity of the external stimulation. We find that, first, the main parameters that regulate network gain are the probabilities of connections from the inhibitory population to the excitatory population and of the connections within the inhibitory population. Second, we show that strict gain control is not achievable in a random network in the second case, when the input recruits an increasing number of neurons. Finally, we confirm that the gain control conditions derived from the mean field approximation are valid in simulations of firing rate models and Hodgkin-Huxley conductance based models