Image reconstruction from in-line Fresnel holograms by using coherent background elimination

Image reconstruction from in-line Fresnel holograms by eliminating a coherent background is studied by computer simulation. The coherent background is calculated by averaging an intensity of a recorded hologram. The quality of the reconstructed image is measured by using a ratio of peak signal to noise. In comparison with the conventional reconstruction method, the results show that the background elimination can improve significantly the quality of the reconstructed images. The text was submitted by the authors in English.     

Use of Raman microscopy and band-target entropy minimization technique to differentiate physical mixture from chemical mixture in mixed metal oxides

Raman microscopy has been applied to characterize physical and chemical mixtures of mixed metal oxides. The obtained Raman mapping data were first subjected to singular value decomposition to obtain the right singular vectors, and the right singular vectors were then subjected to band-target entropy minimization (BTEM) to recover the pure component spectra of the observed species present in the sample. Subsequently, these resolved pure component spectral information was used to differentiate the physical and chemical mixtures. In addition, BTEM is also able to recover the pure component spectra of both unstable compound and its degradation product due to laser irradiation. In current study, the physical mixture of Mn₂O₃ and Co₃O₄, and the chemical mixture of CoMn₂O₄ spinel oxide were investigated.     

Synthesis, characterization and photopolymerization of vinyl ether and acrylate functionalized hybrid oligo-caprolactone

Linear vinyl ether-(oligo-caprolactone)-acrylate (VPCLA), combining fast free radical and complete cationic photopolymerizable groups, was synthesized, functionalized, and photopolymerized to produce polycaprolactone (PCL) network. Fourier Transform Infrared (FTIR) spectra confirmed that the C = C peaks from both vinyl ether and acrylate end groups were consumed after photopolymerization. Kinetics parameters obtained from differential scanning photo-calorimetry (DPC) analysis showed that photopolymerization of VPCLA at early stage was accelerated as the time needed to reach peak maximum was shortened, and the induction time was significantly shortened compared to monofunctional vinyl ether-(oligo-caprolactone) (VPCL). The activation energy (E_a) was calculated to be 14 kJ/mol, assuming second-order autocatalytic model was followed. Rate of polymerization of the hybrid oligomers was doubled in dual photoinitiators system, which contained both cationic and radical photoinitiators. Furthermore, the conversion was greatly improved at the presence of divinyl ether/hydroxybutyl vinyl ether in 1:1 ratio.     

Use of Raman microscopy and band-target entropy minimization analysis to identify dyes in a commercial stamp. Implications for authentication and counterfeit detection

Raman microscopy was used in mapping mode to collect more than 1000 spectra in a 100 microm x 100 microm area from a commercial stamp. Band-target entropy minimization (BTEM) was then employed to unmix the mixture spectra in order to extract the pure component spectra of the samples. Three pure component spectral patterns with good signal-to-noise ratios were recovered, and their spatial distributions were determined. The three pure component spectral patterns were then identified as copper phthalocyanine blue, calcite-like material, and yellow organic dye material by comparison to known spectral libraries. The present investigation, consisting of (1) advanced curve resolution (blind-source separation) followed by (2) spectral data base matching, readily suggests extensions to authenticity and counterfeit studies of other types of commercial objects. The presence or absence of specific observable components form the basis for assessment. The present spectral analysis (BTEM) is applicable to highly overlapping spectral information. Since a priori information such as the number of components present and spectral libraries are not needed in BTEM, and since minor signals arising from trace components can be reconstructed, this analysis offers a robust approach to a wide variety of material problems involving authenticity and counterfeit issues.     

Experimental verifications of a joint transform correlator using compressed reference images

Single-target and multiple-target detections by using a joint transform correlator (JTC) with compressed reference images are experimentally verified. Two high-contrast images with different spatial-frequency content are used as test scenes. Although an effect of the additive noise on detection performance of the proposed correlator is more severe than that of the compression, the experimental results confirm the feasibility of implementing the JTC with compressed reference images.     

Need for Affiliation,Need for Popularity,Self-Esteem,and the Moderating Effect of Big Five Personality Traits Affecting Individuals’ Self-Disclosure on Facebook

The purpose of this study is to explore the moderating effect of Big Five personality traits on the relationship between the predictors (need for affiliation, need for popularity, and self-esteem) and self-disclosure on Facebook. The sample of this study is 354 Facebook users from 5 different cultures in East Asia. A partial least square structural equation modeling data analysis technique was performed to analyze the moderator research framework. This study demonstrates that particular Big Five personality traits moderate each relationship. Specifically, Conscientiousness and Emotional Stability negatively moderate the relationship between need for affiliation and self-disclosure. Agreeableness negatively moderates the relationship between self-esteem and self-disclosure. Openness to New Experience negatively moderates the relationship between need for popularity and self-disclosure. The study suggests the importance of the interaction of personality variables to better understand self-disclosure phenomenon on Facebook. The findings and implications of this study are discussed in the article.     

Extravisceral masses in the peritoneal cavity: sonographically guided biopsies in 52 patients

To establish a possible correlation between the rate of cellular proliferation and already documented functional and morphological characteristics of the rat pineal gland during postnatal development, the bromodeoxyuridine labelling method was used to evaluate the fraction of cells at the S phase of the cell cycle in paraffin sections from 1-, 7-, 14- and 28-day-old rats. Numerical density, taken as an indirect measure of cell hypertrophy, was also evaluated. During the first week after birth the percentage of S phase-cells in the rat pineal gland sharply decreased from around 9% to 1.3%. A smaller but also significant decrease was found from the 7th to the 14th postnatal day where S phase cells were less than 0.5% of all pineal cells. A very low percentage was also seen in samples from 28-day-old rats. Numerical density, namely, the total number of cells per surface unit of pineal section, decreased from birth to the end of the first month. This decrease was also steeper from birth to the 7th postnatal day than at any other period of the study. These results support the idea that a strong expansion of the cellular population of the rat pineal gland precedes morphological and functional maturation and opens the way to further exploration of the relationship between functional and proliferative responses of the pineal gland.     

Influence ofR-curve behaviour on strength degradation due to Hertzian indentation

The influence ofR-curve behaviour on the post-indentation strength of two types of alumina was studied using Hertzian indentation. Soda-lime glass was included in the study to represent a material which does not exhibitR-curve behaviour. Specimens were indented with a spherical indentor with increasing loads. Post-indentation strength was measured in a mineral-oil environment using a ring-on-ring biaxial fixture. Indentation of the two aluminas produced the typical Hertzian crack pattern with a somewhat greater statistical variability than that found in soda-lime glass. The strength of the two aluminas fell into four different regimes that were separated by the onset of ring, cone, and radial crack formation, respectively.R-curve behaviour did not appreciably influence the results, undoubtedly due to the relatively narrow range of indentation loads where failure was controlled by ring and cone cracks. These strength results contrast to those obtained for soda-lime glass. In soda-lime glass, ring and cone crack nucleation occurred simultaneously with a sudden drop in strength followed by a gradual decline in strength with increasing indentation load, in accordance with the prediction of Hertzian cone-crack theory.