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101.
Miguel Angel Sotelo Francisco Javier Rodriguez Luis Magdalena Luis Miguel Bergasa Luciano Boquete 《Autonomous Robots》2004,16(1):95-116
This work describes a color Vision-based System intended to perform stable autonomous driving on unmarked roads. Accordingly, this implies the development of an accurate road surface detection system that ensures vehicle stability. Although this topic has already been documented in the technical literature by different research groups, the vast majority of the already existing Intelligent Transportation Systems are devoted to assisted driving of vehicles on marked extra urban roads and highways. The complete system was tested on the BABIECA prototype vehicle, which was autonomously driven for hundred of kilometers accomplishing different navigation missions on a private circuit that emulates an urban quarter. During the tests, the navigation system demonstrated its robustness with regard to shadows, road texture, and weather and changing illumination conditions. 相似文献
102.
The aim of this work is to provide a high performance air quality simulation using the sulphur transport Eulerian model 2 (STEM-II) program. First of all we optimize the sequential program with the aim of increasing data locality. Then, the optimized program is parallelized using OpenMP shared-memory directives. Experimental results on a 32-processor SGI Origin 2000 show that the parallel program achieves important reductions in the execution times. 相似文献
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106.
R. A. Stern A. Rausch S. Deiker D. Martínez-Galarce L. Shing K. D. Irwin J. N. Ullom G. O’Neil G. Hilton L. Vale 《Journal of Low Temperature Physics》2008,151(3-4):721-726
LMSAL and NIST are developing position-sensitive X-ray strip detectors based on TES microcalorimeter arrays for solar physics.
An important application of these devices will be the study of high temperature (>10 MK) X-ray lines, e.g. Fe XXV, at high
spectral (E/ΔE≥1000) and temporal (sub-ms) resolution. Diagnostics from these lines will provide significant new insights into the physics
of microflares and the early stages of flares. In this paper, we will describe the current status of our laboratory test program
and applicability of our research to future space missions
相似文献
107.
Bogdana Simionescu Irina-Elena Bordianu Magdalena Aflori Florica Doroftei Mihai Mares Xenia Patras Alina Nicolescu Mihaela Olaru 《Materials Chemistry and Physics》2012
The paper reports the first study on hierarchical assemblies (nanofibrillar micelles confined within semi-cylindrical shells) with silsesquioxane and quaternary ammonium units obtained through polymer blending intended for antimicrobial/antifungal stone coatings. The formation of hierarchical structures on solid surfaces is due to the multiple intermolecular ionic interactions, intermolecular Van der Waals and hydrophobic interactions acting among the component molecules. Their antimicrobial/antifungal properties toward the Gram-negative bacteria, Escherichia coli, Gram-positive bacteria, Staphylococcus aureus, and Candida albicans fungus were determined in aqueous solution and were found to be strongly dependent of the topographical features of the coating. 相似文献
108.
Katarzyna Wykpis Magdalena Popczyk Antoni Budniok 《Bulletin of Materials Science》2011,34(4):997-1001
Zn-Ni coatings were deposited under galvanostatic conditions on steel substrate (OH18N9). The influence of current density
of deposition on the surface morphology, chemical and phase composition was investigated. The corrosion resistance of Zn-Ni
coatings obtained at current density 10–25 mA cm−2 are measured, and are compared with that of metallic cadmium coating. Structural investigations were performed by the X-ray
diffraction (XRD) method. The surface morphology and chemical composition of deposited coatings were studied using a scanning
electron microscope (JEOL JSM-6480) with EDS attachment. Studies of electrochemical corrosion resistance were carried out
in the 5% NaCl, using potentiodynamic and electrochemical impedance spectroscopy (EIS) methods. On the ground of these research,
the possibility of deposition of Zn-Ni coatings contained 24–26% at. Ni was exhibited. It was stated, that surface morphology,
chemical and phase composition of these coatings are practically independent on current density of deposition. On the basis
of electrochemical investigations it was found that corrosion resistance of these Zn-Ni coatings is also independent of current
density. These coatings are more corrosion resistant in 5% NaCl solution than metallic cadmium. It was suggested that the
Zn-Ni coating may be used as a substitute for toxic cadmium. 相似文献
109.
Mateusz Schabikowski Magdalena Laskowska Pawe Kowalczyk Andrii Fedorchuk Emma Szri-Doroghzi Zoltn Nmeth Dominika Ku
ma Barbara Gawdzik Aleksandra Wypych Karol Kramkowski ukasz Laskowski 《International journal of molecular sciences》2022,23(15)
In this article, we describe the antimicrobial properties of a new composite based on anodic aluminium oxide (AAO) membranes containing propyl-copper-phosphonate units arranged at a predetermined density inside the AAO channels. The samples were prepared with four concentrations of copper ions and tested as antimicrobial drug on four different strains of Escherichia coli (K12, R2, R3 and R4). For comparison, the same strains were tested with three types of antibiotics using the minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests. Moreover, DNA was isolated from the analysed bacteria which was additionally digested with formamidopyrimidine-DNA glycosylase (Fpg) protein from the group of repair glycosases. These enzymes are markers of modified oxidised bases in nucleic acids produced during oxidative stress in cells. Preliminary cellular studies, MIC and MBC tests and digestion with Fpg protein after modification of bacterial DNA suggest that these compounds may have greater potential as antibacterial agents than antibiotics such as ciprofloxacin, bleomycin and cloxacillin. The described composites are highly specific for the analysed model Escherichia coli strains and may be used in the future as new substitutes for commonly used antibiotics in clinical and nosocomial infections in the progressing pandemic era. The results show much stronger antibacterial properties of the functionalised membranes on the action of bacterial membranes in comparison to the antibiotics in the Fpg digestion experiment. This is most likely due to the strong induction of oxidative stress in the cell through the breakdown of the analysed bacterial DNA. We have also observed that the intermolecular distances between the functional units play an important role for the antimicrobial properties of the used material. Hence, we utilised the idea of the 2D solvent to tailor them. 相似文献
110.
Natalia Janicka Agnieszka Saek Magdalena Sawiska Ernest Kuchar Anna Wiela-Hojeska Katarzyna Karowicz-Bodalska 《International journal of molecular sciences》2022,23(13)
Skin and gastrointestinal cancer cells are the target of research by many scientists due to the increasing morbidity and mortality rates around the world. New indications for drugs used in various conditions are being discovered. Non-opioid analgesics are worth noting as very popular, widely available, relatively cheap medications. They also have the ability to modulate the membrane components of tumor cells. The aim of this review is to analyze the impact of diclofenac, ibuprofen, naproxen, acetylsalicylic acid and paracetamol on skin and gastrointestinal cancers cell membrane. These drugs may affect the membrane through topical application, at the in vitro and in vivo level after oral or parenteral administration. They can lead to up- or downregulated expression of receptors, transporters and other molecules associated with plasma membrane. Medications may also alter the lipid bilayer composition of membrane, resulting in changes in its integrity and fluidity. Described modulations can cause the visualization of cancer cells, enhanced response of the immune system and the initiation of cell death. The outcome of this is inhibition of progression or reduction of tumor mass and supports chemotherapy. In conclusion, non-opioid analgesics may be used in the future as adjunctive therapy for the treatment of these cancers. 相似文献