Telemedicine implementations often remain in the pilot phase and do not succeed in scaling-up to robust products that are used in daily practice. We conducted a qualitative literature review of 45 conference papers describing telemedicine interventions in order to identify determinants that had influenced their implementation. The identified determinants, which would influence the future implementation of telemedicine interventions, can be classified into five major categories: (1) Technology, (2) Acceptance, (3) Financing, (4) Organization and (5) Policy and Legislation. Each category contains determinants that are relevant to different stakeholders in different domains. We propose a layered implementation model in which the primary focus on individual determinants changes throughout the development life cycle of the telemedicine implementation. For success, a visionary approach is required from the multidisciplinary stakeholders, which goes beyond tackling specific issues in a particular development phase. Thus the right philosophy is: 'start small, think big'.

In this study, we argue that important IT change processes affecting an organization's enterprise architecture are also mirrored by a change in the organization's business model. An analysis of the business model may establish whether the architecture change has value for the business. Therefore, in order to facilitate such analyses, we propose an approach to relate enterprise models specified in ArchiMate to business models, modeled using Osterwalder's Business Model Canvas. Our approach is accompanied by a method that supports business model-driven migration from a baseline architecture to a target architecture and is demonstrated by means of a case study. Keywords Business modeling• Enterprise architecture • Business Model Canvas • ArchiMate • Business Model Ontology • Cost/revenue analysis 1 Introduction Many expensive IT innovation projects suffer from the fact that the technical solutions they propose never materialize.

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One of the tasks of network management is to dimension the capacity of access and backbone links. Rules of thumb can be used, but they lack rigor and precision, as they fail to reliably predict whether the quality, as agreed on in the service level agreement, is actually provided. To make better predictions, a more sophisticated mathematical setup is needed. The major contribution of this article is that it presents such a setup; in this a pivotal role is played by a simple, yet versatile, formula that gives the minimum amount of capacity needed as a function of the average traffic rate, traffic variance (to be thought of as a measure of "burstiness"), as well as the required performance level. In order to apply the dimensioning formula, accurate estimates of the average traffic rate and traffic variance are needed. As opposed to the average rate, the traffic variance is rather hard to estimate; this is because measurements on small timescales are needed. We present an easily implementable remedy for this problem, in which the traffic variance is inferred from occupancy statistics of the buffer within the switch or router. To validate the resulting dimensioning procedure, we collected hundreds of traces at multiple (representative) locations, estimated for each of the traces the average traffic rate and (using the approach described above) traffic variance, and inserted these in the dimensioning formula. It turns out that the capacity estimate obtained by the procedure, is usually just a few percent off from the (empirically determined) minimally required value.

The lactose-H+ symport protein (LacS) of Streptococcus thermophilus has a C-terminal hydrophilic domain that is homologous to IIA protein(s) domains of the phosphoenolpyruvate:sugar phosphotransferase system (PTS). C-terminal truncation mutants were constructed and expressed in Escherichia coli and their properties were analyzed. Remarkably, the entire IIA domain (160 amino acids) could be deleted without significant effect on lactose-H+ symport and galactoside equilibrium exchange. The phosphoenolpyruvate:sugar phosphotransferase system (PTS) catalyzes phosphoryl transfer from phosphoenolpyruvate (PEP) to sugars (e.g., glucose) via a number of energycoupling proteins-i.e., enzyme I, heat-stable protein HPr, IIA, and IIB (1). In addition to catalyzing sugar transport, the PTS is involved in regulation of non-PTS transport, carbon and nitrogen metabolism, chemotaxis, and other processes (1-3).In the Gram-negative enteric bacteria, transport of sugars can be regulated at the level of the transport enzyme itself (inducer exclusion) but also at the level of protein expression (induction, catabolite repression) (1, 3). This dual regulation allows an instantaneous response of the organism to the presence or absence of a specific sugar and a slow response, which involves switching on/off the transcription of certain genes. The PTS has a central role in this regulation since the phosphorylation state of the phosphoryl transfer protein IIAGlc affects the activity of various non-PTS transport enzymes (inducer exclusion) as well as cAMP synthesis (catabolite repression). The phosphorylation state of IIAGlc is determined by the balance between phosphorylation via HPr-P and dephosphorylation via IICBGlc in the presence of substrate (e.g., glucose). The result of this regulation is that when Escherichia coli grows in the presence of glucose (PTS sugar) and a non-PTS sugar like lactose or melibiose, diauxic growth is observed with glucose being used first (1, 3).The involvement of IIAGlc or IIA-like proteins in PTSmediated regulation in nonenteric bacteria-e.g., Grampositives-is unclear. The surprising observation has been made, however, that a number of non-PTS sugar transport proteins have a C-terminal extension that is homologous to IIAGIc of E. coli (4). The best-characterized system of this family of transport proteins with a two-domain structure is the lactose transport protein (LacS) of Streptococcus thermophilus (4-8). The LacS protein catalyzes the uptake of galactosides in symport with a proton or exchanges lactose for intracellularly formed galactose (6, 7). The N-terminal (carrier) domain of LacS is typical for a polytopic membrane protein and is composed of 12 a-helical transmembrane segments; the Cterminal IIA domain is hydrophilic and '160 amino acids in size (4). It has been suggested that structurally and functionally distinct domains such as the carrier and IIA part of LacS are connected by interdomain structures (or Q-linkers) that allow the different domains to interact functionally (9).In the prese...