109 resultados para 2196
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We used electrochemical scanning tunneling microscopy to study the intercalation of hydrogen into a Cu(111) model electrode under reactive (in operando) conditions. Hydrogen evolution causes hydrogen intermediates to migrate into the copper lattice as function of the applied potential and the resulting current density. This H-inclusion is demonstrated to be reversible. The presence of subsurface hydrogen leads to a significant surface relaxation/reconstruction affecting both the geometric and electronic structure of the electrode surface.
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Lead is efficiently protected against cathodic corrosion by the addition of diammonium salts in the electrolyte. The cationic coating of the cathode allows the efficient electroreduction of benzamides to benzylamines. The electrochemical deoxygenation of the amide is achieved without the use of oxophilic agents or sacrificial anodes. The surface of the lead cathode stays smooth and the cathode can be reused for multiple runs, providing <2.5 ppm of the crude product. Cyclic voltammetry studies reveal a shift in the onset potential of the hydrogen evolution reaction by −157 mV.
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This book attempts to synthesize research that contributes to a better understanding of how to reach sustainable business value through information systems (IS) outsourcing. Important topics in this realm are how IS outsourcing can contribute to innovation, how it can be dynamically governed, how to cope with its increasing complexity through multi-vendor arrangements, how service quality standards can be met, how corporate social responsibility can be upheld, and how to cope with increasing demands of internationalization and new sourcing models, such as crowdsourcing and platform-based cooperation. These issues are viewed from either the client or vendor perspective, or both. The book should be of interest to all academics and students in the fields of Information Systems, Management, and Organization as well as corporate executives and professionals who seek a more profound analysis and understanding of the underlying factors and mechanisms of outsourcing.
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Information systems (IS) outsourcing projects often fail to achieve initial goals. To avoid project failure, managers need to design formal controls that meet the specific contextual demands of the project. However, the dynamic and uncertain nature of IS outsourcing projects makes it difficult to design such specific formal controls at the outset of a project. It is hence crucial to translate high-level project goals into specific formal controls during the course of a project. This study seeks to understand the underlying patterns of such translation processes. Based on a comparative case study of four outsourced software development projects, we inductively develop a process model that consists of three unique patterns. The process model shows that the performance implications of emergent controls with higher specificity depend on differences in the translation process. Specific formal controls have positive implications for goal achievement if only the stakeholder context is adapted, while they are negative for goal achievement if in the translation process tasks are unintendedly adapted. In the latter case projects incrementally drift away from their initial direction. Our findings help to better understand control dynamics in IS outsourcing projects. We contribute to a process theoretic understanding of IS outsourcing governance and we derive implications for control theory and the IS project escalation literature.
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This book attempts to synthesize research that contributes to a better understanding of how to reach sustainable business value through information systems (IS) outsourcing. Important topics in this realm are how IS outsourcing can contribute to innovation, how it can be dynamically governed, how to cope with its increasing complexity through multi-vendor arrangements, how service quality standards can be met, how corporate social responsibility can be upheld and how to cope with increasing demands of internationalization and new sourcing models, such as crowdsourcing and platform-based cooperation. These issues are viewed from either the client or vendor perspective, or both. The book should be of interest to all academics and students in the fields of Information Systems, Management and Organization as well as corporate executives and professionals who seek a more profound analysis and understanding of the underlying factors and mechanisms of outsourcing.
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A successful bottom-up fill of single Damascene test features is achieved by using a two-component additive package consisting of bis-(sodium-sulfopropyl)-disulfide (SPS) and Imep polymers (polymerizates of imidazole and epichlorohydrin). In addition, a remarkable leveling effect is observed. Clearly, the Imep additive combines bottom-up fill capabilities with leveling characteristics in one single polymer component. These unique hybrid properties of the Imep are rationalized on the basis of an extended N-NDR (N-shaped negative differential resistance) being present in the linear-sweep voltammogram of the SPS/Imep additive system during Cu electrodeposition.
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Nearly 10 years ago the usefulness of poly(ADP-ribose) polymerase (PARP) inhibitors to kill BRCA1 or BRCA2-deficient cells was reported, and this finding has served as a prime example of the concept of synthetic lethality in the context of anticancer therapy. The clinical translation of this finding has undergone several ups and downs, however. Despite spectacular responses seen in some patients with BRCA-deficient breast or ovarian cancers, other patients did not show the expected benefit from PARP inhibitor therapy. Thus, like for all novel tailored anti-cancer drugs, upfront and secondary resistance remain major hurdles in the implementation of the initial preclinical finding. We know at least one clinically relevant mechanism of PARP inhibitor resistance: the reversion of BRCA function by secondary mutations. Nevertheless, it is also clear that this mechanism does not explain all cases of resistance. At the moment, we only have a poor understanding of BRCA reversion-independent resistance mechanisms. Preclinical data have pointed in several directions, e.g. increased drug efflux, reduced drug target levels, or alternative DNA repair. Here, we discuss these mechanisms with a focus on potential DNA repair adaptations.
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Immunotherapy for type I allergies is well established and is regarded to be the most efficient treatment option besides allergen avoidance. As of today, different forms of allergen preparations are used in this regard, as well as different routes of application. Virus-like particles (VLPs) represent a potent vaccine platform with proven immunogenicity and clinical efficacy. The addition of toll-like receptor ligands and/or depot-forming adjuvants further enhances activation of innate as well as adaptive immune responses. CpG motifs represent intensively investigated and potent direct stimulators of plasmacytoid dendritic cells and B cells, while T cell responses are enhanced indirectly through increased antigen presentation and cytokine release. This article will focus on the function of VLPs loaded with DNA rich in nonmethylated CG motifs (CpGs) and the clinical experience gained in the treatment of allergic rhinitis, demonstrating clinical efficacy also if administered without allergens. Several published studies have demonstrated a beneficial impact on allergic symptoms by treatment with CpG-loaded VLPs. Subcutaneous injection of VLPs loaded with CpGs was tested with or without the adjuvant alum in the presence or absence of an allergen. The results encourage further investigation of VLPs and CpG motifs in immunotherapy, either as a stand-alone product or as adjuvants for allergen-specific immunotherapy.
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BACKGROUND E-learning and blended learning approaches gain more and more popularity in emergency medicine curricula. So far, little data is available on the impact of such approaches on procedural learning and skill acquisition and their comparison with traditional approaches. OBJECTIVE This study investigated the impact of a blended learning approach, including Web-based virtual patients (VPs) and standard pediatric basic life support (PBLS) training, on procedural knowledge, objective performance, and self-assessment. METHODS A total of 57 medical students were randomly assigned to an intervention group (n=30) and a control group (n=27). Both groups received paper handouts in preparation of simulation-based PBLS training. The intervention group additionally completed two Web-based VPs with embedded video clips. Measurements were taken at randomization (t0), after the preparation period (t1), and after hands-on training (t2). Clinical decision-making skills and procedural knowledge were assessed at t0 and t1. PBLS performance was scored regarding adherence to the correct algorithm, conformance to temporal demands, and the quality of procedural steps at t1 and t2. Participants' self-assessments were recorded in all three measurements. RESULTS Procedural knowledge of the intervention group was significantly superior to that of the control group at t1. At t2, the intervention group showed significantly better adherence to the algorithm and temporal demands, and better procedural quality of PBLS in objective measures than did the control group. These aspects differed between the groups even at t1 (after VPs, prior to practical training). Self-assessments differed significantly only at t1 in favor of the intervention group. CONCLUSIONS Training with VPs combined with hands-on training improves PBLS performance as judged by objective measures.