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칼슘 알지네이트 캡슐에서 전체 미생물 세포 고정화 방법
No full textA method is provided for immobilization of whole microbial cells containing enzymes in Ca-alginate capsules. Whole microbial cells are mixed with a CaCl.sub.2 solution, a small amount of xanthan gum is added, the resultant mixture is added drop-wise while stirring to a Na-alginate solution containing a small amount of surfactant which is preferably polyoxyethylenesorbitan monolaurate to obtain the capsules containing the cells. The capsules may be washed with distilled water, hardened by in a CaCl.sub.2 solution and incubated in a growth medium. The microbial cells are bacteria or fungi cells and may be recombinant cells
Edge-directed [(M-2)(2)L-4] tetragonal metal-organic polyhedra decorated using a square paddle-wheel secondary building unit
No full textA general strategy was developed for edge-directed self-assembly of tetragonal metal-organic polyhedra (MOPs) having a C-4 symmetry Cu-2(II)(COO)(4) paddle-wheel as a secondary building unit, using C-2 symmetric dicarboxylic ligands as pincer-type primary building units.close202
Metal-Organic Polyhedron Based on a Cu-II Paddle-Wheel Secondary Building Unit at the Truncated Octahedron Corners
No full textSite-directed mutagenesis of Pseudomonas aeruginosa azurin C112D at the M121 position has afforded a series of proteins with elevated Cu-II/I reduction potentials relative to the Cull aquo ion. The high potential and low axial hyperfine splitting (Cu-II electron paramagnetic resonance A(parallel to)) of the C112D/M121L protein are remarkably similar to features normally associated with type 1 copper centers.close353
Highly Sensitive Biomolecule Detection on a Quartz Crystal Microbalance Using Gold Nanoparticles as Signal Amplification Probes
No full textWe report here a novel strategy for the high-sensitive detection of target biomolecules with very low concentrations on a quartz crystal microbalance (QCM) device using gold nanoparticles as signal enhancement probes. By employing a streptavidin-biotin interaction as a model system, we could prepare biotin-conjugated gold nanoparticles maintaining good dispersion and long-term stability by controlling the biotin density on the surface of gold nanoparticles that have been investigated by UV-vis spectra and AFM images. These results showed that 10 mu M N-(6-[biotinamido]hexyl)-3'(2'-pyridyldithio)propionamide (biotin-HPDP) was the critical concentration to prevent the nonspecific aggregation of gold nanoparticles in this system. For sensing streptavidin target molecules by QCM, biotinylated BSA was absorbed on the Au surface of the QCM electrode and subsequent coupling of the target streptavidin to the biotin in the sensing interface followed. Amplification of the sensing process was performed by the interaction of the target streptavidin on the sensing surface with gold nanoparticles modified with 10 mu M biotin-HPDP. The biotinylated gold nanoparticles were used as signal amplification probes to improve the detection limit, which was 50 ng/ml, of the streptavidin detection system without signal enhancement, and the calibration curve determined for the net frequency changes showed good linearity over a wide range from 1 ng/ml to 10 mu g/ml for the quantitative streptavidin target molecule analysis. In addition, the measured dissipation changes suggested that the layer of biotin-BSA adsorbed on the Au electrode and the streptavidin layer assembled on the biotin-BSA surface were highly compact and rigid. On the other hand, the structure formed by the biotinylated gold nanoparticles on the streptavidin layer was flexible and dissipative, being elongated outward from the sensing surface
Saying goodbye is never easy: Why we mourn the end of our favourite TV series
No full textHas the ending of Squid Game left you feeling downhearted? The South Korean megahit struck a nerve with audiences worldwide, with millions logging in to Netflix to follow protagonist Seong Gi-hun and fellow players in their fight for survival over three deadly seasons.
But even if you haven’t seen Squid Game, you’ve probably experienced the sense of loss that comes with the ending of much-loved series. These feelings are very normal, as finales can be deeply meaningful to viewers.</p
Ca-alginate microencapsulation 방법을 이용한 Invertase 활성을 가진 재조합 Saccharomyces cerevisiae의 전세포 효소 고정화
No full text학위논문(석사) - 한국과학기술원 : 화학공학과, 1995.8, [ x, 74 p. ]As a means of integrating cell growth and immobilization into one-step, recombinant Saccharomyces cerevisiae cells with invertase activity were immobilized in liquid-core alginate capsules and cultured to a high density.
The capsules should be made without tails to prevent immobilized cells from leaking. The optimum conditions making the capsules without tails were 1.3% (w/v) calcium chloride and 0.6% (w/v) sodium alginate, respectively, and the amount of the xanthan gum was 20% of the total calcium chloride by weight when the cavity depth was 1.0 cm in the reactor of 7.5 cm in diameter and 3.0 cm in height. When Saccharomyces cerevisiae cells immobilized in the capsules were cultured in the growth medium not containing , the capsules swelled to twice its initial size and the wall became thicker from 0.2 mm to 1.5 mm. But adding 5.0 g to a litre of the growth medium kept the capsule from swelling. To prevent capsules from rupturing because of the formation, 10 g surfactant (Tween 20) was added to a litre of the solution during the step of capsule formation. The capsules with the surfactant did not burst open when the culture was carried out. The dry cell concentration of the cells immobilized into capsules was 83 g/L based on the inner volume.
In batch culture, the specific invertase activity of immobilized cells was similar to that of free cells, although much higher cell concentration was obtained in immobilized cells. Thus, increasing cell density using this microencapsulatioon technique could cause a proportionate increase in total invertase activity. Both free cells and immobilized cells showed a maximum specific invertase activity at the same temperature of 65℃, but the thermal stability of invertase of immobilized cells was better than that of free cells. It was concluded that the optimum reaction temperature was between 30℃ and 50℃ considering both maximum activity and thermal stability. When the immobilized cells were s...한국과학기술원 : 화학공학과
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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