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201.
SIMD computer systems offer tremendous potential speed-ups but aggressive compilation strategies are required to realize this potential. The paper presents the Compass SIMD compiler technology developed while working on a number of SIMD compilers. Although the various targets have much in common, our increased understanding of the SIMD compilation process on each successive project and the differences in the targets themselves has affected the shape of each compiler. 相似文献
202.
Andreas Blanc Lukas Deimling Norbert Eisenreich 《Propellants, Explosives, Pyrotechnics》2002,27(3):185-189
Spectral characteristics of ultraviolet and infrared rocket plume signatures are of great importance especially for detection, identification and tracking of approaching missiles. The objective was to find out significant differences between plume signatures of available real rocket motors based on double base and composite propellants. Therefore, the spectral emission ranges of 305–385 nm (UV) and 1.7–14 μm (MIR) were measured from the head‐on aspect. Additionally, reaction processes of applied propellant compositions were calculated by the ICT Thermodynamic‐Code and taken for the simulation of the theoretical spectra based on the ICT Band Modelling‐Code (BAM). 相似文献
203.
S. Vollmer A. Birkner S. Lukas G. Witte Ch. Wll 《Materialwissenschaft und Werkstofftechnik》2000,31(9):845-849
Nanostructuring of Copper Surfaces by means of Oxygen induced Reconstructions For metal single crystals the topography of vicinal surfaces can be changed in a controlled fashion by means of oxygen adsorption. This self‐organized phenomenon will be demonstrated for several vicinal copper surfaces. For densely packed copper surfaces with terrace lengths of ≤ 1 nm oxygen adsorption causes a doubling of terrace length and step height, whereas an oxygen‐induced mesoscopic faceting into periodic nano‐stripes is observed for regular monoatomic stepped surfaces with longer terraces. The width of the resulting nano‐stripes depends on the orientation of the clean vicinal surfaces and values of 10 to 50 nm have been observed. The thermal stability of the surfaces is found to increase with the stripes width, some structures are stable for temperatures up to 800 K. 相似文献
204.
Bernhard Schick Lukas Pillong Gentiana Wenzel Silke Wemmert 《International journal of molecular sciences》2022,23(4)
The etiology of juvenile angiofibroma (JA) has been a controversial topic for more than 160 years. Numerous theories have been proposed to explain this rare benign neoplasm arising predominately in adolescent males, focusing mainly on either the vascular or fibrous component. To assess our hypothesis of JA’s being a malformation arising from neural crest cells/remnants of the first branchial arch plexus, we performed immunohistochemical analyses of neural crest stem cells (NCSC) and epithelial-mesenchymal transition (EMT) candidates. Immunoexpression of the NCSC marker CD271p75 was observed in all investigated JA’s (n = 22), mainly around the pathological vessels. Close to CD271p75-positive cells, high MMP3-staining was also observed. Additionally, from one JA with sufficient material, RT-qPCR identified differences in the expression pattern of PDGFRβ, MMP2 and MMP3 in MACS®-separated CD271p75positive vs. CD271p75 negative cell fractions. Our results, together with the consideration of the literature, provide evidence that JA’s represent a malformation within the first branchial arch artery/plexus remnants deriving from NCSC. This theory would explain the typical site of tumor origin as well as the characteristic tumor blood supply, whereas the process of EMT provides an explanation for the vascular and fibrous tumor component. 相似文献
205.
Hongfang Jin Angie Dong Liu Lukas Holmberg Manman Zhao Siyao Chen Jinyan Yang Yan Sun Shanshan Chen Chaoshu Tang Junbao Du 《International journal of molecular sciences》2013,14(5):10465-10482
The authors investigated the regulatory effects of sulfur dioxide (SO2) on myocardial injury induced by isopropylarterenol (ISO) hydrochloride and its mechanisms. Wistar rats were divided into four groups: control group, ISO group, ISO plus SO2 group, and SO2 only group. Cardiac function was measured and cardiomyocyte apoptosis was detected. Bcl-2, bax and cytochrome c (cytc) expressions, and caspase-9 and caspase-3 activities in the left ventricular tissues were examined in the rats. The opening status of myocardial mitochondrial permeability transition pore (MPTP) and membrane potential were analyzed. The results showed that ISO-treated rats developed heart dysfunction and cardiac injury. Furthermore, cardiomyocyte apoptosis in the left ventricular tissues was augmented, left ventricular tissue bcl-2 expression was down-regulated, bax expression was up-regulated, mitochondrial membrane potential was significantly reduced, MPTP opened, cytc release from mitochondrion into cytoplasm was significantly increased, and both caspase-9 and caspase-3 activities were increased. Administration of an SO2 donor, however, markedly improved heart function and relieved myocardial injury of the ISO-treated rats; it lessened cardiomyocyte apoptosis, up-regulated myocardial bcl-2, down-regulated bax expression, stimulated mitochondrial membrane potential, closed MPTP, and reduced cytc release as well as caspase-9 and caspase-3 activities in the left ventricular tissue. Hence, SO2 attenuated myocardial injury in association with the inhibition of apoptosis in myocardial tissues, and the bcl-2/cytc/caspase-9/caspase-3 pathway was possibly involved in this process. 相似文献
206.
Media photo‐degradation in pharmaceutical biotechnology – impact of ambient light on media quality,cell physiology,and IgG production in CHO cultures
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Lukas Neutsch Paul Kroll Matthias Brunner Alexander Pansy Michael Kovar Christoph Herwig Tobias Klein 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2018,93(8):2141-2151
BACKGROUND
Many vital components in bioprocess media are prone to photo‐conversion or photo‐degradation upon exposure to ambient light, with severe negative consequences for biomass yield and overall productivity. However, there is only limited awareness of light irradiation as a potential risk factor when working in transparent glass bioreactors, storage vessels or disposable bag systems. The chemical complexity of most media renders a root‐cause analysis difficult. This study investigated in a novel, holistic approach how light‐induced changes in media composition relate to alterations in radical burden, cell physiology, morphology, and product formation in industrial Chinese hamster ovary (CHO) bioprocesses.RESULTS
Two media formulations from proprietary and commercial sources were tested in a pre‐hoc light exposure scenario prior to cultivation. Using fluorescence excitation/emission (EEM) matrix spectroscopy, a photo‐sensitization of riboflavin was identified as a likely cause for drastically decreased IgG titers (up to ?80%) and specific growth rates (?50% to ?90%). Up to three‐fold higher radical levels were observed in photo‐degraded medium. On the biological side, this resulted in significant changes in cell morphology and aberrations in the normal IgG biosynthesis/secretion pathway.CONCLUSION
These findings clearly illustrate the underrated impact of room light after only short periods of exposure, occurring accidentally or knowingly during bioprocess development and scale‐ up. The detrimental effects, which may share a common mechanistic cause at the molecular level, correlate well with changes in spectroscopic properties. This offers new perspectives for online monitoring concepts, and improved detectability of such effects in future. © 2018 The Authors. Journal of Chemical Technology & Biotechnology published by JohnWiley & Sons Ltd on behalf of Society of Chemical Industry.207.
Lukas Novotny 《Journal of the American Ceramic Society》2002,85(5):1057-1060
We present a near-field optical technique which makes use of the strongly enhanced optical field at a laser-illuminated metal tip. The enhanced field is used to locally excite the sample under investigation by multiphoton absorption. An optical scan image with spatial resolutions down to 20 nm is established by detecting the emitted fluorescence. The principle of the method is described and experimental results are demonstrated for samples of J-aggregates of PIC dye molecules. Ongoing experiments on nanocomposite, Er3+ -doped oxyfluoride glass-ceramics are discussed. 相似文献
208.
Sarah K. Hakuno Ellis Michiels Eleonore B. Kuhlemaijer Ilse Rooman Lukas J. A. C. Hawinkels Marije Slingerland 《International journal of molecular sciences》2022,23(6)
Cancers affecting the gastrointestinal system are highly prevalent and their incidence is still increasing. Among them, gastric and pancreatic cancers have a dismal prognosis (survival of 5–20%) and are defined as difficult-to-treat cancers. This reflects the urge for novel therapeutic targets and aims for personalised therapies. As a prerequisite for identifying targets and test therapeutic interventions, the development of well-established, translational and reliable preclinical research models is instrumental. This review discusses the development, advantages and limitations of both patient-derived organoids (PDO) and patient-derived xenografts (PDX) for gastric and pancreatic ductal adenocarcinoma (PDAC). First and next generation multicellular PDO/PDX models are believed to faithfully generate a patient-specific avatar in a preclinical setting, opening novel therapeutic directions for these difficult-to-treat cancers. Excitingly, future opportunities such as PDO co-cultures with immune or stromal cells, organoid-on-a-chip models and humanised PDXs are the basis of a completely new area, offering close-to-human models. These tools can be exploited to understand cancer heterogeneity, which is indispensable to pave the way towards more tumour-specific therapies and, with that, better survival for patients. 相似文献
209.
Michael Kilian Theresa Bunse Wolfgang Wick Michael Platten Lukas Bunse 《International journal of molecular sciences》2021,22(23)
Despite extensive preclinical research on immunotherapeutic approaches, malignant glioma remains a devastating disease of the central nervous system for which standard of care treatment is still confined to resection and radiochemotherapy. For peripheral solid tumors, immune checkpoint inhibition has shown substantial clinical benefit, while promising preclinical results have yet failed to translate into clinical efficacy for brain tumor patients. With the advent of high-throughput sequencing technologies, tumor antigens and corresponding T cell receptors (TCR) and antibodies have been identified, leading to the development of chimeric antigen receptors (CAR), which are comprised of an extracellular antibody part and an intracellular T cell receptor signaling part, to genetically engineer T cells for antigen recognition. Due to efficacy in other tumor entities, a plethora of CARs has been designed and tested for glioma, with promising signs of biological activity. In this review, we describe glioma antigens that have been targeted using CAR T cells preclinically and clinically, review their drawbacks and benefits, and illustrate how the emerging field of transgenic TCR therapy can be used as a potent alternative for cell therapy of glioma overcoming antigenic limitations. 相似文献
210.