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121.
Christian Heuser Mario Marpe Andreas Wucher 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(4):601-604
The kinetic excitation of a solid surface under bombardment with energetic particles is studied via internal electron emission in a metal-insulator-metal junction. In particular, the dependence of the measured tunneling yield on the projectile impact angle is studied. The resulting impact angle distribution is compared with predictions of the total excitation energy profile calculated using the SRIM 2006 Monte Carlo program package. While the calculated profiles fail to explain the experimental data, it is shown that a simple calculation of impact angle dependent projectile backscattering qualitatively reproduces the observed trends. 相似文献
122.
123.
Christian Friebe Martin D. Hager Andreas Winter Ulrich S. Schubert 《Advanced materials (Deerfield Beach, Fla.)》2012,24(3):332-345
Electropolymerization represents a suitable and well‐established approach for the assembly of polymer structures, in particular with regard to the formation of thin, insoluble films. Utilization of monomers that are functionalized with metal complex units allows the combination of structural and functional benefits of polymers and metal moieties. Since a broad range of both electropolymerizable monomers and metal complexes are available, various structures and, thus, applications are possible. Recent developments in the field of synthesis and potential applications of metal‐functionalized polymers obtained via electropolymerization are presented, highlighting the significant advances in this field of research. 相似文献
124.
Andrea Bagn Jos A. Morales-García Christian Grin-Ferr Caridad Díaz Jos Prez del Palacio Maria C. Ramos Francisca Vicente Beln Prez Jos Brea María Isabel Loza Merc Palls Carmen Escolano 《International journal of molecular sciences》2022,23(10)
The impact of neurodegenerative diseases (ND) is becoming unbearable for humankind due to their vast prevalence and the lack of efficacious treatments. In this scenario, we focused on imidazoline I2 receptors (I2-IR) that are widely distributed in the brain and are altered in patients with brain disorders. We took the challenge of modulating I2-IR by developing structurally new molecules, in particular, a family of bicyclic α-iminophosphonates, endowed with high affinity and selectivity to these receptors. Treatment of two murine models, one for age-related cognitive decline and the other for Alzheimer’s disease (AD), with representative compound B06 ameliorated their cognitive impairment and improved their behavioural condition. Furthermore, B06 revealed beneficial in vitro ADME-Tox properties. The pharmacokinetics (PK) and metabolic profile are reported to de-risk B06 for progressing in the preclinical development. To further characterize the pharmacological properties of B06, we assessed its neuroprotective properties and beneficial effect in an in vitro model of Parkinson’s disease (PD). B06 rescued the human dopaminergic cell line SH-SY5Y from death after treatment with 6-hydroxydopamine (6-OHDA) and showed a crucial anti-inflammatory effect in a cellular model of neuroinflammation. This research reveals B06 as a putative candidate for advancing in the difficult path of drug discovery and supports the modulation of I2-IR as a fresh approach for the therapy of ND. 相似文献
125.
This paper discusses the life cycle of decentralized smart contracts, i.e. digital and executable representations of rights and obligations in a multi-party environment. The life cycle relies on blockchain technology, i.e. a distributed digital ledger, to ensure proper implementation and integrity of the smart contracts. The life cycle consists of four subsequent phases: Creation, freezing, execution, and finalization. For each phase actors and technological services are identified and explained in detail. With the life cycle at hand, risks and limitations of smart contracts and the underlying blockchain technology are briefly discussed. 相似文献
126.
127.
Charlotte Szewczykowski Christian Mardin Marianna Lucio Gerd Wallukat Jakob Hoffmanns Thora Schrder Franziska Raith Lennart Rogge Felix Heltmann Michael Moritz Lorenz Beitlich Julia Schottenhamml Martin Herrmann Thomas Harrer Marion Ganslmayer Friedrich E. Kruse Martin Krter Jochen Guck Robert Lmmer Matthias Zenkel Andreas Gießl Bettina Hohberger 《International journal of molecular sciences》2022,23(13)
Long COVID (LC) describes the clinical phenotype of symptoms after infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Diagnostic and therapeutic options are limited, as the pathomechanism of LC is elusive. As the number of acute SARS-CoV-2 infections was and is large, LC will be a challenge for the healthcare system. Previous studies revealed an impaired blood flow, the formation of microclots, and autoimmune mechanisms as potential factors in this complex interplay. Since functionally active autoantibodies against G-protein-coupled receptors (GPCR-AAbs) were observed in patients after SARS-CoV-2 infection, this study aimed to correlate the appearance of GPCR-AAbs with capillary microcirculation. The seropositivity of GPCR-AAbs was measured by an established cardiomyocyte bioassay in 42 patients with LC and 6 controls. Retinal microcirculation was measured by OCT–angiography and quantified as macula and peripapillary vessel density (VD) by the Erlangen-Angio Tool. A statistical analysis yielded impaired VD in patients with LC compared to the controls, which was accentuated in female persons. A significant decrease in macula and peripapillary VD for AAbs targeting adrenergic β2-receptor, MAS-receptor angiotensin-II-type-1 receptor, and adrenergic α1-receptor were observed. The present study might suggest that a seropositivity of GPCR-AAbs can be linked to an impaired retinal capillary microcirculation, potentially mirroring the systemic microcirculation with consecutive clinical symptoms. 相似文献
128.
Intramyocardial Inflammation after COVID-19 Vaccination: An Endomyocardial Biopsy-Proven Case Series
Christian Baumeier Ganna Aleshcheva Dominik Harms Ulrich Gross Christian Hamm Birgit Assmus Ralf Westenfeld Malte Kelm Spyros Rammos Philip Wenzel Thomas Münzel Albrecht Elssser Mudather Gailani Christian Perings Alae Bourakkadi Markus Flesch Tibor Kempf Johann Bauersachs Felicitas Escher Heinz-Peter Schultheiss 《International journal of molecular sciences》2022,23(13)
Myocarditis in response to COVID-19 vaccination has been reported since early 2021. In particular, young male individuals have been identified to exhibit an increased risk of myocardial inflammation following the administration of mRNA-based vaccines. Even though the first epidemiological analyses and numerous case reports investigated potential relationships, endomyocardial biopsy (EMB)-proven cases are limited. Here, we present a comprehensive histopathological analysis of EMBs from 15 patients with reduced ejection fraction (LVEF = 30 (14–39)%) and the clinical suspicion of myocarditis following vaccination with Comirnaty® (Pfizer-BioNTech) (n = 11), Vaxzevria® (AstraZenica) (n = 2) and Janssen® (Johnson & Johnson) (n = 2). Immunohistochemical EMB analyses reveal myocardial inflammation in 14 of 15 patients, with the histopathological diagnosis of active myocarditis according the Dallas criteria (n = 2), severe giant cell myocarditis (n = 2) and inflammatory cardiomyopathy (n = 10). Importantly, infectious causes have been excluded in all patients. The SARS-CoV-2 spike protein has been detected sparsely on cardiomyocytes of nine patients, and differential analysis of inflammatory markers such as CD4+ and CD8+ T cells suggests that the inflammatory response triggered by the vaccine may be of autoimmunological origin. Although a definitive causal relationship between COVID-19 vaccination and the occurrence of myocardial inflammation cannot be demonstrated in this study, data suggest a temporal connection. The expression of SARS-CoV-2 spike protein within the heart and the dominance of CD4+ lymphocytic infiltrates indicate an autoimmunological response to the vaccination. 相似文献
129.
An Experimental Comparison of the Maintainability of Object-Oriented and Structured Design Documents
Lionel C. Briand Christian Bunse John W. Daly Christiane Differding 《Empirical Software Engineering》1997,2(3):291-312
Several important questions still need to be answered regarding the maintainability of object-oriented design documents. This paper focuses on the following issues: are object-oriented design documents easier to understand and modify than structured design documents? Do they need to comply with quality guidelines such as the ones provided by Coad and Yourdon? What is the impact of such quality standards on the understandability and modifiability of design documents? Answers can be based on informed opinion or empirical evidence. Since software technology investments are substantial and contradictory opinions exist regarding design strategies, performing empirical studies on these topics is a relevant research activity. This paper presents a controlled experiment performed with computer science students as subjects. Results strongly suggest that quality guidelines based on Coad and Yourdon principles have a beneficial effect on the maintainability of object-oriented design documents. However, there is no strong evidence regarding the alleged higher maintainability of object-oriented design documents over structured design documents. Furthermore, results suggest that object-oriented design documents are more sensitive to poor design practices, in part because their cognitive complexity becomes increasingly unmanageable. However, because our ability to generalise these results is limited, they should be considered as preliminary, i.e., it is very likely that they can only be generalised to programmers with little object-oriented training and programming experience. Such programmers can, however, be commonly found on maintenance projects. As well as additional research, external replications of this study are required to confirm the results and achieve confidence in these findings. 相似文献
130.
Mario Pukall Christian Kästner Walter Cazzola Sebastian Götz Alexander Grebhahn Reimar Schröter Gunter Saake 《Software》2013,43(2):153-185
Software is changed frequently during its life cycle. New requirements come, and bugs must be fixed. To update an application, it usually must be stopped, patched, and restarted. This causes time periods of unavailability, which is always a problem for highly available applications. Even for the development of complex applications, restarts to test new program parts can be time consuming and annoying. Thus, we aim at dynamic software updates to update programs at runtime. There is a large body of research on dynamic software updates, but so far, existing approaches have shortcomings either in terms of flexibility or performance. In addition, some of them depend on specific runtime environments and dictate the program's architecture. We present JavAdaptor , the first runtime update approach based on Java that (a) offers flexible dynamic software updates, (b) is platform independent, (c) introduces only minimal performance overhead, and (d) does not dictate the program architecture. JavAdaptor combines schema changing class replacements by class renaming and caller updates with Java HotSwap using containers and proxies. It runs on top of all major standard Java virtual machines. We evaluate our approach's applicability and performance in non‐trivial case studies and compare it with existing dynamic software update approaches. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献