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91.
This paper considers several aspects of natural visual attention and its link to wider notions of awareness, natural and artificial, in the context of foveated vision. It builds on a theory of abductive perception; a formal definition for an artificial or robot perceptual system, using objects represented as feature clouds. It proposes a broad, but unifying approach to several aspects of visual attention in the light of this, including autonomic eye gaze movements, aspects of secondary and covert attention, and exogenous (sense driven) and endogenous (task driven) attention. Modes of attentional lapse, commonly referred to as inattentional blindness and change blindness, are also discussed in the context of the model presented. 相似文献
92.
Andrzej Witkowski Bernard Cedro Agnieszka Kierzek Damian Baranowski 《Hydrobiologia》2009,631(1):155-172
This study focuses on diatom assemblages occurring in cores of Late-glacial and Holocene deposits retrieved from the mouth of the lower Rega River valley, of the southern coast of the Baltic Sea. Sediment samples from four cores were the subject of the present study. Diatom-inferred environmental characteristics, e.g., water level; water salinity (conductivity), trophic status and pH, within each core are presented. Diatom assemblage zones (DAZ) were distinguished, based on differences in the distribution of particular ecological groups. Each DAZ appears to be related to environmental changes during the deposition of a given sediment interval. The Late-glacial (Allerød) sediments originated in a shallow lake with increasing concentrations of solutes and nutrients. The Holocene record begins in the early Atlantic Chronozone and the diatoms point to weakly brackish-water sediments deposited in a shallow water environment. During the period of 8,500–5,800 cal year BP sedimentation took place in a shallow embayment and/or lagoon. From ca. 5,800 cal year BP onwards sedimentation took place in a peat bog environment alternating with Aeolian deposition. Changes in diatom community structure imply a close relationship with the climate-controlled eustatic rise of the ocean level and its consequence Littorina transgression. As with other southern Baltic Sea localities, brackish-water diatoms appear in the sediments, signaling the onset of marine transgression somewhat earlier than previously accepted. Differences and similarities in diatom assemblages and the palaeogeographic development of nearby regions within the Baltic Sea basin and lagoons (coastal areas) from different geographic regions, are also discussed. 相似文献
93.
Tomasz Jarzembowski Agnieszka Jóźwik Katarzyna Wiśniewska Jacek Witkowski 《Current microbiology》2010,61(5):407-410
We studied the usefulness of flow cytometry for detection of vancomycin resistance in Enterococcus faecalis by direct binding of commercially available fluorescent vancomycin to cells obtained from culture. The cells were stained
with Vancomycin@FL, sonicated and additionally stained with propidium iodide (PI). Regarding to inductive mechanism of vanA-mediated vancomycin resistance, resistant reference strain was also pre-incubated with vancomycin. PI staining divided cells
into two subpopulations. There were significantly lower mean FL1 fluorescence values and mean fluorescence per particle (FL1/FSC)
in reference vancomycin-resistant strain than in reference and clinical strains sensitive to this antibiotic. Pre-incubation
with vancomycin of vancomycin resistant enterococci strain modified Vancomycin@FL binding, however, cells remained easy to
differ. We have demonstrated new, quick and sensitive method for detection of vancomycin resistant strains of E. faecalis. The study proved possibility of detection of vancomycin resistance caused by presence of vanA gene by staining cells with Vancomycin@FL. Flow cytometry approach study of E. faecalis vancomycin resistance by detection of Vancomycin@FL binding to the bacterial cells. 相似文献
94.
A. Zembron-Lacny M. Slowinska-Lisowska Z. Szygula Z. Witkowski K. Szyszka 《Journal of physiology and biochemistry》2010,66(1):15-21
The aim of this study was to follow up whether the modification of pro-antioxidant status by 8-day oral application of N-acetylcysteine
(NAC) in healthy men affects the haematological response, whether there is a direct relationship between antioxidant defences
and erythropoietin (EPO) secretion and whether NAC intake enhances exercise performance. Fifteen healthy men were randomly
assigned to one of two groups: control or NAC (1,200 mg d−1 for 8 days prior to and 600 mg on the day of exercise trial). To measure the ergogenic effectiveness of NAC, subjects performed
incremental cycle exercise until exhaustion. NAC administration significantly influenced the resting and post-exercise level
of glutathione (+31%) as well as the resting activity of glutathione enzymes (glutathione reductase, −22%; glutathione peroxidase,
−18%). The oxidative damage markers, i.e., protein carbonylation and lipid peroxidation products (thiobarbituric acid reactive
substance) were reduced by NAC by more than 30%. NAC noticeably affected the plasma level of EPO (+26%), haemoglobin (+9%),
haematocrit (+9%) and erythrocytes (−6%) at rest and after exercise. The mean corpuscular volume and the mean corpuscular
haemoglobin increased by more than 12%. Plasma total thiols increased by 17% and directly correlated with EPO level (r = 0.528, P < 0.05). NAC treatment, contrary to expectations, did not significantly affect exercise performance. Our study has shown that
8-day NAC intake at a daily dose of 1,200 mg favours a pro-antioxidant status and affects haematological indices but does
not enhance exercise performance. 相似文献
95.
Plewczynski D Tkacz A Wyrwicz LS Godzik A Kloczkowski A Rychlewski L 《Journal of molecular modeling》2006,12(4):453-461
Our algorithm predicts short linear functional motifs in proteins using only sequence information. Statistical models for
short linear functional motifs in proteins are built using the database of short sequence fragments taken from proteins in
the current release of the Swiss-Prot database. Those segments are confirmed by experiments to have single-residue post-translational
modification. The sensitivities of the classification for various types of short linear motifs are in the range of 70%. The
query protein sequence is dissected into short overlapping fragments. All segments are represented as vectors. Each vector
is then classified by a machine learning algorithm (Support Vector Machine) as potentially modifiable or not. The resulting
list of plausible post-translational sites in the query protein is returned to the user. We also present a study of the human
protein kinase C family as a biological application of our method. 相似文献
96.
Zemojtel T Fröhlich A Palmieri MC Kolanczyk M Mikula I Wyrwicz LS Wanker EE Mundlos S Vingron M Martasek P Durner J 《Trends in plant science》2006,11(11):524-5; author reply 526-8
97.
The heterogeneous nuclear ribonucleoprotein (hnRNP) K homology (KH) domain is an evolutionarily conserved module that binds short ribonucleotide sequences. KH domains most often are present in multiple copies per protein. In vitro studies of hnRNP K and other KH domain bearing proteins have yielded conflicting results regarding the relative contribution of each KH domain to the binding of target RNAs. To assess this RNA-binding we used full-length hnRNP K, its fragments and the yeast ortholog as baits in the yeast three-hybrid system. The results demonstrate that in this heterologous in vivo system, the three KH domains bind RNA synergistically and that a single KH domain, in comparison, binds RNA weakly. 相似文献
98.
Strekowski L Say M Zegrocka O Tanious FA Wilson WD Manzel L Macfarlane DE 《Bioorganic & medicinal chemistry》2003,11(6):1079-1085
Six dimeric 2-(2-naphthyl)quinolin-4-amines with a linker between the amino groups and eight dimeric 2-(4-anilino)quinolin-4-amines linked between the anilino groups were synthesized and evaluated for their interaction with duplex/triplex DNA's and as antagonists of immunostimulatory oligodeoxynucleotides with a CpG-motif (CpG-ODN). The most powerful triple-helix DNA intercalator known to date, with high affinity toward T.A.T triplets and triplex/duplex selectivity, was found. The potent antagonism of immunostimulatory CpG-ODN by several bis-4-aminoquinolines is not related to their DNA interactions. 相似文献
99.
Intracoronary beta irradiation (use of beta radiation for intracoronary irradiation) is an effective method in reducing neointimal proliferation after successful angioplasty and stent implantation. However, long-term results may be influenced by absolute dose and by the homogeneity in dose distribution. In our study, we investigated dose perturbation due to the presence of a conventional guide wire during irradiation. The Galileo III centering catheter and P-32 beta source were used. The 55 MD GAF Chromic foil was positioned within a phantom made of PMMA. The dose distribution at cylindrical surfaces has been assessed using GAF Chromic dosimetric foil MD55 (Nuclear Associates, USA). Our study demonstrated the significant dose reduction of 46% in the most "shaded" area. The dose reduction to 80% or less occupy the 60 degrees sector. This phenomenon can cause progression of late restenosis. In conclusion, the results suggest that technical improvements in centering catheter construction should be made to eliminate the "shielding" effect of the guide wire. 相似文献
100.
Thad E Wilson Jian Cui Rong Zhang Sarah Witkowski Craig G Crandall 《Journal of applied physiology》2002,93(1):85-91
Orthostatic tolerance is reduced in the heat-stressed human. The purpose of this project was to identify whether skin-surface cooling improves orthostatic tolerance. Nine subjects were exposed to 10 min of 60 degrees head-up tilting in each of four conditions: normothermia (NT-tilt), heat stress (HT-tilt), normothermia plus skin-surface cooling 1 min before and throughout tilting (NT-tilt(cool)), and heat stress plus skin-surface cooling 1 min before and throughout tilting (HT-tilt(cool)). Heating and cooling were accomplished by perfusing 46 and 15 degrees C water, respectively, though a tube-lined suit worn by each subject. During HT-tilt, four of nine subjects developed presyncopal symptoms resulting in the termination of the tilt test. In contrast, no subject experienced presyncopal symptoms during NT-tilt, NT-tilt(cool), or HT-tilt(cool). During the HT-tilt procedure, mean arterial blood pressure (MAP) and cerebral blood flow velocity (CBFV) decreased. However, during HT-tilt(cool), MAP, total peripheral resistance, and CBFV were significantly greater relative to HT-tilt (all P < 0.01). No differences were observed in calculated cerebral vascular resistance between the four conditions. These data suggest that skin-surface cooling prevents the fall in CBFV during upright tilting and improves orthostatic tolerance, presumably via maintenance of MAP. Hence, skin-surface cooling may be a potent countermeasure to protect against orthostatic intolerance observed in heat-stressed humans. 相似文献