First Target (first + target)

Distribution by Scientific Domains


Selected Abstracts


Design of Experiments (DOE) for the Optimization of Titania,hydroxyapatite Functionally Graded Coatings

INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 4 2009
Valeria Cannillo
Titania,hydroxyapatite functionally graded coatings were deposited on titanium alloy substrates by plasma spraying. Because it was necessary to spray together the titania and the hydroxyapatite powders to obtain the graded system, the first target of the present study was to optimize the process parameters in order to obtain a high-quality coating. A 23 Design of Experiments was applied to define the optimal values of plasma torch power, hydrogen flux, and spraying distance. This defined set of parameters (38 kW, 5 SLPM, and 90 mm, respectively) was used to spray the most promising graded coating, which was characterized and postheat treated. [source]


On the saliency of negative stimuli: Evidence from attentional blink1

JAPANESE PSYCHOLOGICAL RESEARCH, Issue 1 2004
Tokihiro Ogawa
Abstract:, When people are asked to detect two targets from a rapid serial visual presentation (RSVP) stream, impairment of recognition of the second target (T2) can be observed if the T2 is presented several hundred milliseconds later than the first target (T1). This phenomenon is known as attentional blink, and is considered to reflect some temporal characteristic of the attentional process. The aim of the present study was to use the attentional blink paradigm to examine whether the affective meaning of the stimuli could affect the magnitude of attentional blink. In Experiment 1, the valence of the T2 (neutral, positive, and negative) was manipulated. Significant T2 detection deficit was observed with neutral and positive T2 but not with negative T2. Experiment 2 demonstrated that non-significant attentional blink in negative T2 in Experiment 1 could be attributed to the negative affective meaning of T2. Results are discussed in terms of the high saliency of negative information. [source]


The hair follicle melanocytes in vitiligo in relation to disease duration

JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 8 2009
T S Anbar
Abstract Background and aims, Vitiligo is an acquired pigmentary disorder of skin and hair. Active melanocytes in hair follicles can be detected by DOPA and immunohistochemical staining, while amelanotic melanocytes can only be detected by the latter. None of the studies on hair melanocytes in vitiligo discussed the effect of disease duration on these melanocytes. Here, we study the presence of melanotic and amelanotic melanocytes in vitiligo hair follicles and statistically correlating their presence with the disease duration. Methods, This study was conducted on 30 patients with vitiligo and 10 normal volunteers. Three biopsies were taken from each patient: two from black and white hairs from vitiliginous areas and the third from apparently normal skin of the same patients. Sections were stained by DOPA reaction and NKI/beteb then examined for the presence of melanocytes. The presence of melanocytes and the disease duration were correlated statistically using the t -test. Results, Active melanocytes were detected in black hairs of 6.7% of vitiligo patients and in 100% of apparently normal skin of the same patients and controls. On examining black hairs of the 28 vitiligo patients with negative DOPA reaction, 19 of them (67.9%) showed positive NKI/beteb stain. Disease duration was inversely correlated with the melanocytes' presence within hair follicles. Melanocytes were absent from 100% of white hairs. Conclusions, The melanotic melanocytes were the first target of the disease process followed by the amelanotic melanocytes. Since the disappearance of the latter was inversely correlated with the disease duration, early treatment in vitiligo is advised. Conflicts of interest None declared. [source]


Intramodal and crossmodal processing delays in the attentional blink paradigm revealed by event-related potentials

PSYCHOPHYSIOLOGY, Issue 5 2008
Alexia Ptito
Abstract In the attentional blink (AB), processing of a second target (T2) is impaired if it is presented shortly after the onset of a first target (T1), leading to a decrease in accurate report of T2 if T2 is masked. Some prominent theories of the AB suggest that an amodal bottleneck in working memory consolidation underlies the AB. We investigated this by factorially manipulating T1 and T2 modalities (visual or auditory) using equivalent stimuli and tasks in both modalities to minimize task switching. T2 was not masked. In all modality combinations, the electrophysiological P3 component to T2, obtained by subtracting T1 only trials from T1+T2 trials, was delayed and reduced in amplitude when T2 was presented soon after T1 relative to when T1 and T2 were presented farther apart. Results provide support for a common amodal bottleneck that underlies the AB effects observed in all visual/auditory modality combinations. [source]