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231.
With the exponential growth of moving objects data to the Gigabyte range, it has become critical to develop effective techniques
for indexing, updating, and querying these massive data sets. To meet the high update rate as well as low query response time
requirements of moving object applications, this paper takes a novel approach in moving object indexing. In our approach,
we do not require a sophisticated index structure that needs to be adjusted for each incoming update. Rather, we construct conceptually
simple short-lived index images that we only keep for a very short period of time (sub-seconds) in main memory. As a consequence, the resulting technique
MOVIES supports at the same time high query rates and high update rates, trading this property for query result staleness. Moreover, MOVIES is the first main memory method supporting time-parameterized predictive queries. To support this feature, we present two
algorithms: non-predictive MOVIES and predictive MOVIES. We obtain the surprising result that a predictive indexing approach—considered state-of-the-art in an external-memory scenario—does
not scale well in a main memory environment. In fact, our results show that MOVIES outperforms state-of-the-art moving object indexes such as a main-memory adapted B
x
-tree by orders of magnitude w.r.t. update rates and query rates. In our experimental evaluation, we index the complete road
network of Germany consisting of 40,000,000 road segments and 38,000,000 nodes. We scale our workload up to 100,000,000 moving
objects, 58,000,000 updates per second and 10,000 queries per second, a scenario at a scale unmatched by any previous work. 相似文献
232.
233.
Lukas Seebauer Yanni Schneider Alice Drobny Sonja Pltz Tomas Koudelka Andreas Tholey Iryna Prots Beate Winner Friederike Zunke Jürgen Winkler Wei Xiang 《International journal of molecular sciences》2022,23(3)
Parkinson’s disease (PD) is neuropathologically characterized by the loss of dopaminergic neurons and the deposition of aggregated alpha synuclein (aSyn). Mounting evidence suggests that neuritic degeneration precedes neuronal loss in PD. A possible underlying mechanism could be the interference of aSyn with microtubule organization in the neuritic development, as implied by several studies using cell-free model systems. In this study, we investigate the impact of aSyn on microtubule organization in aSyn overexpressing H4 neuroglioma cells and midbrain dopaminergic neuronal cells (mDANs) generated from PD patient-derived human induced pluripotent stem cells (hiPSCs) carrying an aSyn gene duplication (SNCADupl). An unbiased mass spectrometric analysis reveals a preferential binding of aggregated aSyn conformers to a number of microtubule elements. We confirm the interaction of aSyn with beta tubulin III in H4 and hiPSC-derived mDAN cell model systems, and demonstrate a remarkable redistribution of tubulin isoforms from the soluble to insoluble fraction, accompanied by a significantly increased insoluble aSyn level. Concordantly, SNCADupl mDANs show impaired neuritic phenotypes characterized by perturbations in neurite initiation and outgrowth. In summary, our findings suggest a mechanistic pathway, through which aSyn aggregation interferes with microtubule organization and induces neurite impairments. 相似文献
234.
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
235.
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
236.
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
237.
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
238.
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
239.
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
240.
Chittaranjan Ray Ashish Babbar Bunnie Yoneyama Lukas Sheild Benjamin Respicio Cheryl Ishii 《Clean Technologies and Environmental Policy》2013,15(2):345-357
Following a natural disaster, access to safe drinking water by the affected population is a high priority. Low cost water purification systems, which can be used for both short-term (immediate) and long-term (sustainable) response to serve the needs of the affected communities, are ideal for these scenarios. The University of Hawaii has developed three low cost water purification technologies for use during humanitarian assistance and disaster relief (HA/DR) missions. A UH team participated in joint USA and partner nation training exercises, such as Crimson Viper 2010 and 2011, organized by the Marine Corps Forces Pacific Experimentation Center (MEC) in Sattahip, Thailand, to demonstrate the effectiveness of these technologies to purify water from local sources. Three technologies were selected for Crimson Viper 2010: (1) a backpack filter unit, (2) a bicycle pump powered reverse osmosis (RO) unit, and (3) a model slow sand filtration unit. For Crimson Viper 2011, improved versions of the backpack and RO units were deployed. This article discusses and evaluates the results obtained during the demonstration of the three technologies at these exercises. 相似文献