Nonlinear optical properties of mushroom-shaped CdSe/CdS coreshells.

Ma, S M,Seo, J T,Yu, W,Yang, Q,Tabibi, B,Temple, D,Namkung, M,Heo, J,Kim, W J,Jung, S S American Scientific Publishers 2009 Journal of nanoscience and nanotechnology Vol.9 No.2

<P>The third-order nonlinear optical susceptibilities of mushroom-shaped CdSe/CdS coreshells as a function of concentration have been investigated using polarization- and concentration-resolved degenerate four-wave mixing in a resonant region. The effective third-order nonlinear optical susceptibilities, /chi(3)xxxx/ and /chi(3)xyyx/ of CdSe/CdS coreshells were estimated to be approximately 1.86 x 10(-21)-1.03 x 10(-20) m2/V2, and approximately 0.45 x 10(-21)-6.15 x 10(-21) m2/V2, respectively, for various concentrations of approximately 0.64 x 10(-3)-4.95 x 10(-3) mol/m3. The second hyperpolarizabilities, /<gammah>xxxx/ and /<gammah>xyyx/, of CdSe/CdS coreshells were extracted to be approximately 2.37 x 10(-41) m5/V2 and approximately 1.29 x 10(-41) m5/V2, respectively.</P>

Optical spectroscopy of PPV-based block copolymers of nanostructured supramolecular organic semiconductor.

Yang, Q,Battle, R,Zhang, C,Ma, S M,Seo, J T,Tabibi, B,Temple, D,Sun, S,Jung, S S,Namkung, M American Scientific Publishers 2009 Journal of nanoscience and nanotechnology Vol.9 No.2

<P>The third-order nonlinearity of a PPV-based nanostructured supramolecular organic semiconductor (DBAB), with an electron donor (D) connected to an electron acceptor (A) via nonconjugated and flexible bridge (B) units, was investigated in this work at both near-resonant (532 nm) and nonresonant (1064 nm) wavelength by using degenerate four-wave mixing. The second hyperpolarizabilities of D, A, and DBAB at 532 nm were found to be approximately 2.42 x 10(-43) m2/V2, 7.75 x 10(-44) m2/V2, and 1.80 x 10(-43) m2/V2 in copolarization geometry, and approximately 1.59 x 10(-43) m2/V2, 2.59 x 10(-44) m2/V2, and 1.18 x 10(-43) m2/V2 in orthogonal polarization geometry, respectively. The second hyperpolarizabilities of DBAB at 1064 nm were approximately 1.66 x 10(-46) m2/V2 and approximately 8.77 x 10(-47) m2/V2 for parallel and orthogonal polarization cases.</P>

상안검거근의 절제에 의한 안검하수의 교정에 대한 임상적고찰

마홍수,조문제,조해석,위성신,최오규 大韓成形外科學會 1986 Archives of Plastic Surgery Vol.13 No.2

The great number of operations described over the past century for correcting blepharoptosis is indicative of the difficulty of achieving a standardized technique. It will be consistently effective condition that has so many variations of degree and individual operative technique is so important. To obtain the best surgical results in blapharoptosis, it is necessary to select the appropriate operation for each case according to levator function, degree of ptosis, its etiology and the others. In generally, if the levator function is poor or abscent, sling of the upper lid to frontalis muscle is recommended and if levator function is good, resection of the levator is the treatment of choice. But some authors (Blaskovics & Jaensch) believe that resection of the levator will give an excellent result even when little preoperative levator action is evident. Authors have experienced 25 patients (27 eyes) of the moderate to severe degree of blepharoptosis who have received the levator resection, from January 1980 to January 1984 and could have done follow up studies for at least 6 months. The results were obtained as follows; 1. In most cases, the patients were satisfied except 6 cases complicated; one case of entropion and five cases of undercorrection. 2. Even if levator function was poor (below 2 mm, 7 cases), good surgical results have been obtained by resection of levator(21-25 mm or above).

Third-Order Nonlinear Susceptibility and Hyperpolarizability of CdSe Nanocrystals with Femtosecond Excitation

Seongmin Ma,JaeTae Seo,A. Jackson,B. Tabibi,H. Brown,K. Lee,L. Creekmore,M. Namkung,Q. Yang,R. Battle,S. S. Jung,T. Skyles,W. Yu 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.6

Single beam femtosecond Z-scan spectroscopy at 775 nm revealed that the effective third-order nonlinear susceptibility and hyperpolarizability of CdSe colloidal nanocrystals near the Bohr radius were 0.7 . 1.0 × 10.22 m2/V2 and 0.18 . 2.0 × 10.44 m5/V2, respectively. The non-resonant nonlinearity increase for CdSe colloidal quantum dots with bigger than average diameters is attributed to their absorption cross-section being larger and their bandgap energy being narrower than those of the quantum dots with smaller sizes.

Highly Porous Silica Nanoaerogels for Ultrafast Nonlinear Optical Applications

Seo, Jae Tae,Ma, S.M.,Lee, K.,Brown, H.,Jackson, A.,Skyles, T.,Cubbage, N.M.,Tabibi, B.,Yoo, K.P.,Kim, Suk Young,Jung, S.S.,Namkung, M. Trans Tech Publications, Ltd. 2005 Key Engineering Materials Vol.287 No.-

<P>Highly porous silica nanoaerogels with low apparent density of ~0.1 g/cm3 and ~0.07 g/cm3 were synthesized through two-step sol-gel processing and low temperature supercritical fluid drying. The nonlinear refraction (γ) of silica nanoaerogels was estimated to be ~ -3.4 x 10-16 m2/W for ~0.1 g/cm3 and ~0.07 g/cm3 apparent densities with a signal-beam femtosecond z-scan spectroscopy. The third-order nonlinear refraction coefficient of nanostructure silica nanoaerogels was almost four orders larger than that of bulk silica materials. The large nonlinearrefraction with high nonlinear figure of merit (γ/βλ, β~2×10-10 m/W for 0.07 g/cm3 apparent density, β~6×10-10 m/W for 0.1 g/cm3 apparent density, λ~0.775 µm) is an ideal optical property for nonlinear applications of homeland security, battlefield enhancement, and industrial uses.</P>

Analysis of virulence traits of Staphylococcus aureus isolated from bovine mastitis in semi-intensive and family dairy farms

Jaquelina J. Guzmán-Rodríguez,Ma. Fabiola León-Galván,José E. Barboza-Corona,Mauricio Valencia-Posadas,Pedro D. Loeza-Lara,Mónica Sánchez-Ceja,Alejandra Ochoa-Zarzosa,Joel E. López-Meza,Abner J. Gutié 대한수의학회 2020 Journal of Veterinary Science Vol.21 No.5

Background: Staphylococcus aureus is one of the main microorganisms that causes bovine mastitis, and its well-known virulence characteristics and interactions with the environment are used to aid the design of more efficient therapies. Objectives: To determine whether the virulence traits, such as antibiotic resistance and biofilm-forming and internalization abilities, of S. aureus isolated from bovine mastitis are related to dairy production system types. Methods: The study was performed in the Mexican states of Guanajuato and Michoacan. Semi-intensive dairy farms (SIDFs) and family dairy farms (FDFs) (454 and 363 cows, respectively) were included. The 194 milk samples from mastitis affected quarters were collected and 92 strains of S. aureus were isolated and identified by biochemical and molecular tests. Antibiotic resistance, biofilm and internalization assays were performed on 30 randomly selected isolated strains to determine virulence traits, and these strains were equally allocated to the 2 dairy production systems. Results: All 30 selected strains displayed a high degree of resistance (50%–91.7%) to the antibiotics tested, but no significant difference was found between SIDF and FDF isolates. S. aureus strains from SIDFs had an average biofilm forming capacity of up to 36% (18.9%–53.1%), while S. aureus strains from FDFs registered an average of up to 53% (31.5%–77.8%) (p > 0.05). Internalization assays revealed a higher frequency of internalization capacity for strains isolated from FDFs (33.3%) than for those isolated from SIDFs (6.7%) (p > 0.05). fnbpA gen was detected in 46.6% of FDF strains and 33.3% of SIDF strains, and this difference was significant (p < 0.05). Conclusions: Our findings show that the virulence traits of S. aureus isolates analyzed in this study, depend significantly on several factors, such as phenotype, genotype, and environmental conditions, which are significantly related to dairy production system type and daily management practices.

Large Optical Nonlinearity of Highly Porous Silica Nanoaerogels in the Nanosecond Time Domain

JaeTae Seo,A. Jackson,B. Tabibi,H. Brown,K. Lee,K. P. Yoo,L. Creekmore,M. Namkung,Q. Yang,R. Battle,S. M. Ma,S. S. Jung,S. Y. Kim,T. Skyles 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.48 No.6

The nonlinear optical properties of highly porous silica nanoaerogels with a 0.1 g/cm3 apparent density were investigated using a spatially Gaussian shaped, 8 ns pulsed laser operating at a wavelength of 532 nm with a repetition rate of 10 Hz. Closed Z-scan spectroscopy revealed the negative nonlinearity (or defocusing effect) of the silica nanoaerogels. The third-order nonlinear susceptibility of silica nanoaerogels was estimated to be 9.6 × 10.19 m2/V2 (6.9 × 10.11 esu) from degenerate four-wave mixing measurements. The nonlinear transmittance limiting threshold of silica nanoaerogels was 17 MW/cm2.F

MnBi 다층 변조 박막의 주기 두께에 따른 자기적 성질

마혜선,김미양,이장로 숙명여자대학교 자연과학연구소 1993 자연과학논문집 Vol.- No.4

Bi-Mn multilayer were deposited in vacuum by repeating an alternate evaporation of Bi and Mn metals. MnBi composited films were prepared by annealing (under Ar atmosphere) Bi-Mn multilayer. X-ray diffractometer was used for verifying whether the films prepared grew to the orientation of MnBi(002). The magnetization and coercive force of films were studied using VSM. The study showed that MnBi composite films have the easy axis oriented perpendiculur to the film when the repetition number is N=1 and N=2. Also it showed that as the periodic thickness length shorter, the magnetization was decreased while the coercive force was increased.

초기성인의 생활습관과 당뇨에 대한 지식

소선이,마지은,고지윤,김은혜,박현화,서유진,서형은,유은미,이하늬,이혜인,정지연,현혜리,이자형,정덕유,강지숙 이화여자대학교 간호과학대학 2009 이화간호학회지 Vol.- No.43

Purposes :The purposes of this study was to investigate the self-managing status according to the life styles and the diabetic knowledge of early adulthood. The subjects in this study were 240people, the early adult aged twenties to thirties living in the metropolitan area. Data were collected by using self-administered questionnaires that measure about the knowledge of diabetes; the dietetic behavior; the knowledge of diet; the exercise behavior; the knowledge of exercise. Descriptive statistics, t-test, ANOVA, and correlation were used for data analysis. Result :1. At the knowledge of diabetes degree based on the general character, the subjects who had experiences of diabetic education have higher degree of the diabetic knowledge. 2. At the knowledge of diabetes degree according to the life style, the subjects who have regular diet are appeared highly. Also the subjects who don't take much food of animal origin have higher degree. 3. At the knowledge of diet based on the life style, the subjects who don't keep three times meals a day are appeared highly. Also the subjects who have regular diet have higher degree. 4. At the knowledge of exercise according to the life style, the subjects who take extra nutritions 3-4 times a week are appeared highly. Although the subjects tend to know about dietary, exercise and health management, it showed that they actually don't perform what they know in their everyday of life. The reason for this could be the lack of perceived seriousness about diabetes mellitus. Thus as nursing professionals, we should provide them proper health education and support. Moreover, advanced research on the empowerment is warranted.

Roughness influence on the sheet resistance of the PEDOT:PSS printed on paper

Rogerio M. Morais,Maykel S. Klem,Maíza S. Ozorio,Tiago C. Gomes,Neri Alves 한국물리학회 2018 Current Applied Physics Vol.18 No.2

The use of paper as a platform to manufacture organic electronic devices, electronic paper, has expanding potential for many applications because of several properties offered. In this work, we show a study of PEDOT:PSS printed by inkjet on bond paper, vegetal paper and sheets of PET. The relation between the surface density of the deposited material, morphology and resistivity was investigated for samples printed with a commercial Hewlett-Packard(HP)® printer and Microsoft Word® software. The amount of material deposited, i.e. surface density, was controlled using the print number in the same position and changing the gray scale used in the image formation. Changing the surface density of printed PEDOT:PSS, it is possible to produce a continuous film permeating the papers fibers. Sheet resistances obtained, when 7.0 mg cm−2 of PEDOT:PSS were deposited on the surfaces, were: (a) 413.2 kΩ/Sq for bond paper, (b) 5.6 kΩ/Sq for vegetable paper and (c) 2.3 kΩ/Sq for PET. The exponential dependence of sheet resistance with the surface density of printed material allows us to evaluate the strong influence of substrate roughness on PEDOT:PSS conductivity and to predict, for each one, conditions to minimize it.