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61.
The role of the subicular complex and entorhinal cortex (SUB–EC) in spatial learning was examined in 2 water maze experiments. In Experiment 1, rats had to locate a hidden platform that was always a fixed distance and direction from an intramaze landmark. Each day, the landmark and platform were moved to a new location. Both control and SUB–EC-lesioned rats learned to locate the platform equally readily during training. However, the control group was impaired in locating the platform when the visual extramaze cues were concealed, whereas the lesioned group was unaffected by this manipulation. In Experiment 2, the lesioned rats were impaired in finding a hidden platform that was in a fixed place in the water maze and showed no evidence of having learned its location in a probe test. These results suggest that damage to the SUB–EC impairs the integration of geometric information but spares a more general navigational-directional strategy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Knaust Thiemo Felnhofer Anna Kothgassner Oswald D. Hllmer Helge Gorzka Robert-Jacek Schulz Holger 《Virtual Reality》2022,26(3):925-938
Virtual Reality - It is generally accepted that natural environments reduce stress and improve mood. Since access to natural environments is sometimes limited, virtual natural environments,... 相似文献
63.
Jongchan Kim Thilini Batagoda Jaesang Lee Daniel Sylvinson Kan Ding Patrick J. G. Saris Ushasree Kaipa Iain W. H. Oswald Mohammad A. Omary Mark E. Thompson Stephen R. Forrest 《Advanced materials (Deerfield Beach, Fla.)》2019,31(32)
Orienting light‐emitting molecules relative to the substrate is an effective method to enhance the optical outcoupling of organic light‐emitting devices. Platinum(II) phosphorescent complexes enable facile control of the molecular alignment due to their planar structures. Here, the orientation of Pt(II) complexes during the growth of emissive layers is controlled by two different methods: modifying the molecular structure and using structural templating. Molecules whose structures are modified by adjusting the diketonate ligand of the Pt complex, dibenzo‐(f,h)quinoxaline Pt dipivaloylmethane, (dbx)Pt(dpm), show an ≈20% increased fraction of horizontally aligned transition dipole moments compared to (dbx)Pt(dpm) doped into a 4,4′‐bis(N‐carbazolyl)‐1,1′‐biphenyl, CBP, host. Alternatively, a template composed of highly ordered 3,4,9,10‐perylenetetracarboxylic dianhydride monolayers is predeposited to drive the alignment of a subsequently deposited emissive layer comprising (2,3,7,8,12,13,17,18‐octaethyl)‐21H,23H‐porphyrinplatinum(II) doped into triindolotriazine. This results in a 60% increase in horizontally aligned transition dipole moments compared to the film deposited in the absence of the template. The findings provide a systematic route for controlling molecular alignment during layer growth, and ultimately to increase the optical outcoupling in organic light‐emitting diodes. 相似文献
64.
65.
GB Rosson DJ Hazen-Martin JA Biegel MC Willingham AJ Garvin BW Oswald L Wainwright NA Brownlee CF Wright 《Canadian Metallurgical Quarterly》1998,11(12):1228-1237
Malignant rhabdoid tumor (MRT) is a rare, enigmatic childhood cancer characterized by extreme aggressiveness and resistance to chemotherapy. To understand better the origin of the tumor and the mechanisms by which it develops and resists treatment, five cell lines were established from patients presenting with MRT (two renal and three extrarenal tumors). All of the cell lines display the light microscopic and ultrastructural features, as well as the variable immunohistochemical profile, characteristic of MRT. All are capable of forming tumors in nude mice. Three of the cell lines have detectable abnormalities of chromosome 22: one a t(22, 22) unbalanced translocation and two others a loss of heterozygosity of polymerase chain reaction-based microsatellite markers. Northern blot analysis showed that overexpression of the c-myc message was a consistent characteristic of the five MRTs evaluated. Although mutations of the p53 gene were not detectable by sequence analysis, all of the cell lines showed nuclear accumulation of the p53 protein by an immunocytochemical analysis in a minority of the cells. This result suggests that dysfunction in a p53-dependent apoptotic pathway might play a role in the multiple drug resistance phenotype of these tumors. 相似文献
66.
Complementary tunneling transistor for low power application 总被引:1,自引:0,他引:1
P. -F. Wang K. Hilsenbeck Th. Nirschl M. Oswald Ch. Stepper M. Weis D. Schmitt-Landsiedel W. Hansch 《Solid-state electronics》2004,48(12):2281-2286
The metal oxide semiconductor field effect transistor (MOSFET) is scaling to a “tunneling epoch”, in which multiple leakage current induced by different tunneling effects exist. The complementary Si-based tunneling transistors are presented in this paper. The working principle of this device is investigated in detail. It is found that the band-to-band tunneling current is be controlled by the gate-to-source voltage. Due to the reverse biased p-i-n diode structure, an ultra-low leakage current is achieved. The sub-threshold swing of TFET is not limited by kt/q, which is the physical limit of the MOSFET. Using the CMOS compatible processes, the complementary TFETs (CTFET) are fabricated on one wafer. From a circuit point of view, the compatibility between TFET and MOSFET enables the transfer of CMOS circuits to CTFET circuits. 相似文献
67.
68.
Urodynamics encompass a number of functional tests of the lower and occasionally the upper urinary tract. These tests comprise uroflowmetry, cystometry or measurement of bladder pression during bladder filling and voiding, urethral pressure profile, electromyography (EMG) of the external urethral sphincter, pressure-flow studies and video-urodynamics. Alone or in combination these examinations have become essential elements of urological clinical work-up, since they do not only allow to precisely classify a functional disorder but also to establish an adequate therapy. Urodynamics are nowadays standard in any urological department. 相似文献
69.
X. Wang E. Perzon F. Oswald F. Langa S. Admassie M.R. Andersson O. Ingans 《Advanced functional materials》2005,15(10):1665-1670
Plastic solar cells have been fabricated using a low‐bandgap alternating copolymer of fluorene and a donor–acceptor–donor moiety (APFO‐Green1), blended with 3′‐(3,5‐bis‐trifluoromethylphenyl)‐1′‐(4‐nitrophenyl)pyrazolino[70]fullerene (BTPF70) as electron acceptor. The polymer shows optical absorption in two wavelength ranges, λ < 500 nm and 600 < λ < 1000 nm. The BTPF70 absorbs light at λ < 700 nm. A broad photocurrent spectral response in the wavelength range 300 < λ < 1000 nm is obtained in solar cells. A photocurrent density of 3.4 mA cm–2, open‐circuit voltage of 0.58 V, and power‐conversion efficiency of 0.7 % are achieved under illumination of AM1.5 (1000 W m–2) from a solar simulator. Synthesis of BTPF70 is presented. Photoluminescence quenching and electrochemical studies are used to discuss photoinduced charge transfer. 相似文献
70.
The solubility of titanium nitride in liquid iron is described by the solubility product log([%Ti][%N])1 = ?17040/T + 6.40 reported by Turkdogan. The solubility in δ ferrite measured by Kunze is log<[%Ti][%N])δ = ?17205/T + 5.56. Combining the solubilities in both phases and the solubilities of nitrogen the distribution equilibrium of titanium can be derived. It is characterized by the thermodynamic distribution coefficient kδ/Io,Ti = [%Ti]δ/[%Ti] = 0.40. By zone melting and secondary ion mass spectrometry of the titanium distribution kδ/ITi = 0.53 was measured. An analysis of all known data led to kδ/Io,Ti = 0.40…0.50. Measurements of the TiN solubility in austenite by heat treatment were not significant. They led to distribution coefficients between 0.07 and > 1. By zone melting in a carburizing atmosphere a distribution coefficient kγ/ITi = 0.12 was measured. From a thermodynamic analysis performed by Ohtani et al., from the TiN solubility in the melt, and from the solubilities of nitrogen kγ/Io,Ti = 0.13 was deduced. Basing on the distribution equilibria of titanium and nitrogen and on the measured temperature dependence the solubility product log([%Ti][%N])γ = ?15000/T + 4.06 was obtained. 相似文献