1,442 research outputs found
The Impact of Service Complexity on New Service Development – A Contingency Approach
This dissertation explores the limitations and impact on performance of applying formalised NPD processes in service innovation. Hypotheses build on a structural framework of organisational factors, which have been linked to successful product innovation but have not been consistently supported in a service context. Evidence is presented for a moderating influence of service complexity on the relationship between factors relating to NSD process organisation and new service performance. The findings create a link between product and service innovation and demonstrate that whereas complex new services benefit from formalised development processes and structure, services with lower complexity do not
The users who touched the ceiling of scratch
AbstractThe Scratch programming environment is widely known for its high accessibility for novice users, especially children. Recently it has also been adopted in introductory computer science courses in universities where first empirical results show that users with prior programming experience were less satisfied than others. In this paper we analyze this specific aspect by identifying difficulties that experienced programmers had with Scratch during a four-day workshop. The experiences of this particular user group suggest adding some standard integrated development environment features to Scratch. Beyond these results we argue that this obvious route might hide the real problem of discoverability of Scratch's features
The Exotic Baryon Theta^+(1540) on the Lattice
We report on a study of the pentaquark Theta^+(1540), using a variety of
different interpolating fields. We use Chirally Improved fermions in
combination with Jacobi smeared quark sources to improve the signal and get
reliable results even for small quark masses. The results of our quenched
calculations, which have been done on a 12^3x24 lattice with a lattice spacing
of a=0.148 fm, do not provide any evidence for the existence of a Theta^+ with
positive parity. We do observe, however, a signal compatible with nucleon-kaon
scattering state. For the negative parity the results are inconclusive, due to
the potential mixture with nucleon-kaon and N*-kaon scattering states.Comment: 6 pages, 1 figure, Proceedings of "Lattice 2005" (Dublin, 25-30 July
2005
SOTIF-Compliant Scenario Generation Using Semi-Concrete Scenarios and Parameter Sampling
Scenario-based testing is considered state-of-the-art to verify and validate
Advanced Driver Assistance Systems or Automated Driving Systems. Due to the
official launch of the SOTIF-standard (ISO 21448), scenario-based testing
becomes more and more relevant for releasing those Highly Automated Driving
Systems. However, an essential missing detail prevent the practical application
of the SOTIF-standard: How to practically generate scenarios for scenario-based
testing? In this paper, we perform a Systematic Literature Review to identify
techniques that generate scenarios complying with requirements of the
SOTIF-standard. We classify existing scenario generation techniques and
evaluate the characteristics of generated scenarios wrt. SOTIF requirements. We
investigate which details of the real-world are covered by generated scenarios,
whether scenarios are specific for a system under test or generic, and whether
scenarios are designed to minimize the set of unknown and hazardous scenarios.
We conclude that scenarios generated with existing techniques do not comply
with requirements implied by the SOTIF-standard; hence, we propose directions
for future research.Comment: accepted at IEEE ITSC 202
Baryon spectroscopy with spatially improved quark sources
We study baryons on the lattice with a special focus on excited states. For
that purpose we construct several interpolators which differ in their Dirac
structure. These interpolators are built from Jacobi smeared quarks with
different widths in order to allow for operators with improved spatial
wavefunctions. We compute all cross correlations and use the variational method
to determine which combinations of operators have best overlap with ground and
excited states. Our approach yields promising results for the spin-1/2 baryons:
nucleon, sigma, xi and lambda. For the spin-3/2 baryons, delta and omega, we
obtain results which are consistent with results of other groups.Comment: LaTeX [PoS], 6 pages, 4 figures, talk presented at Lattice 2005
(Hadron spectrum and quark masses
Crystal Structure of an Anti-Ang2 CrossFab Demonstrates Complete Structural and Functional Integrity of the Variable Domain.
Bispecific antibodies are considered as a promising class of future biotherapeutic molecules. They comprise binding specificities for two different antigens, which may provide additive or synergistic modes of action. There is a wide variety of design alternatives for such bispecific antibodies, including the "CrossMab" format. CrossMabs contain a domain crossover in one of the antigen-binding (Fab) parts, together with the "knobs-and-holes" approach, to enforce the correct assembly of four different polypeptide chains into an IgG-like bispecific antibody. We determined the crystal structure of a hAng-2-binding Fab in its crossed and uncrossed form and show that CH1-CL-domain crossover does not induce significant perturbations of the structure and has no detectable influence on target binding
Bone involvement in patients with lymphoma: the role of FDG-PET/CT
Purpose: To evaluate the diagnostic impact and clinical significance of FDG-avid bone lesions detected by FDG-PET/CT in patients with lymphoma. Methods: The study population comprised 50 consecutive patients (mean age 41.7±15.5years; 27 female, 23 male; 41 staging, 9 restaging) with Hodgkin's disease (n=22) or aggressive non-Hodgkin's lymphoma (n=28) in whom FDG-avid bone lesions were detected by FDG-PET/CT. All patients had either direct biopsy of the FDG-avid bone lesion (n=18), standard bone marrow biopsy at the iliac crest (BMB; n=43) or both procedures (n=11). In 15 patients, additional MRI of the bone lesions was performed. All patients underwent FDG-PET/CT after the end of treatment. All CT images of FDG-PET/CT scans were analysed independently regarding morphological osseous changes and compared with FDG-PET results. Results: In the 50 patients, 193 FDG-avid lesions were found by PET/CT. The mean standardised uptake value was 6.26 (±3.22). All direct bone biopsies (n=18) of the FDG-avid lesions proved the presence of lymphomatous infiltration. BMB (n=43) was positive in 12 patients (27.9%). In CT, 32 of 193 (16.6%) lesions were detected without the PET information. No additional morphological bone infiltration was detected on CT compared with FDG-PET. All morphological bone alterations on CT scans persisted after the end of therapy. Additional PET/CT information regarding uni- or multifocal bone involvement resulted in lymphoma upstaging in 21 (42%) patients compared with the combined information provided by CT and BMB. Conclusion: In patients with FDG-avid bone lesions, FDG-PET is superior to CT alone or in combination with unilateral BMB in detecting bone marrow involvement, leading to upstaging in a relevant proportion of patient
Response to combination therapy with interferon alfa-2a and ribavirin in chronic hepatitis C according to a TNF-alpha promoter polymorphism
Background. Tumor necrosis factor-alpha (TNF-alpha) is involved in the pathogenesis of chronic active hepatitis C. Polymorphisms in the promoter region of the TNF-alpha gene can alter the TNF-alpha expression and modify the host immune response. The present study aimed at the correlation of the G308A TNF-alpha polymorphism with the response to antiviral combination therapy in chronic hepatitis C. Patients and Methods: 62 patients with HCV and 119 healthy unrelated controls were genotyped for the G308A TNF-alpha promoter polymorphism. The patients received 3 x 3 million units of interferon alfa-2a and 1,0001,200 mg ribavirin daily according to their body weight. A response was defined as absence of HCV-RNA and normalization of S-ALT after 6 months of combination therapy. Results:With respect to the allele and genotype frequency, a significant difference was not observed between controls and patients with chronic hepatitis C. Furthermore, such a difference was also not observed if responders and non-responders to antiviral therapy were compared. Conclusions: The promoter polymorphism of the TNF-alpha gene investigated herein is equally distributed in healthy individuals and patients with hepatitis C and does not seem to predict the response to therapy with interferon alfa-2a and ribavirin. Copyright (C) 2003 S. Karger AG, Basel
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