• Journal of Magnetics
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• v.18 no.3
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• pp.235-239
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• 2013

The effect of Dy addition on the microstructure and magnetic properties of the sintered NdFeB magnets was investigated. The results of the microstructure analysis showed that Dy-free and Dy-doped samples are composed of $Nd_2Fe_{14}B$ (P42/mnm) and a trace of Nd-rich phase. Dy addition reduces significantly the pole density factor of (004), (006) and (008) crystal faces as estimated by the Horta formula. Accordingly, the coercivity of the Dy-doped sample increases from 2038 $kA{\cdot}m^{-1}$ up to 2288 $kA{\cdot}m^{-1}$. The $H_{cj}(T)/M_s(T)$ versus $H^{min}_N/M_s(T)$ (Kronm$\ddot{u}$ller-plot) behavior shows that the nucleation is the dominating mechanism for the magnetization reversal in these two kinds of magnets, and two microstructural parameters of ${\alpha}_k$ and $N_{eff}$ are obtained. The Kronm$\ddot{u}$ller-Plot gives evidence for an increase of the ${\alpha}_k$ responsible for an increase of the coercivity as the result of the increase of the magnetic field as the magnetic domain reversed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9171-9176
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• 2014

Aim: P53, the most commonly mutated tumor suppressor gene in all types of human cancer, is involved in cell cycle arrest and control of apoptosis. Although p53 contains several polymorphic sites, the codon 72 polymorphism is by far more common. There are divergent reports but many studies suggest p53 pro/pro SNP may be associated with susceptibility to developing various cancers in different regions of the world. The present study aimed to find any correlation between H. pylori infection and progression of carcinogenesis, by studying apoptosis and the p53 gene in gastric biopsies from north Indian population. Materials and Methods: A total of 921 biopsies were collected and tested for prevalence of H. pylori by rapid urease test (RUT), imprint cytology and histology. Apoptosis was studied by the TUNEL method. Analysis of p53 gene polymorphism at codon 72 was accomplished by PCR using restriction enzyme BstU1. Observation: Out of 921 samples tested 56.7% (543) were H. pylori positive by the three techniques. The mean apoptotic index (AI) in the normal group was 2.12, while gastritis had the maximum 4.24 followed by gastric ulcer 2.28, gastropathy 2.22 and duodenal ulcer 2.08. Mean AI in cases with gastric cancer (1.72) was less than the normal group. The analysis of p53 72 SNP revealed that p53 (Arg/Arg), (Pro /Arg) variant are higher (40.59% & 33.66%) as compared to p53 pro/pro variant (25.74%) inthe healthy population. Conclusions: The North Indian population harbors Arg or Pro/Arg SNP that is capable of withstanding stress conditions; this may be the reason of low incidence of gastric disease in spite of high infection with H. pylori. There was no significant association with H. pylori infection and AI. However, there is increased apoptosis in gastritis which may occur independent of H. pylori or p53 polymorphism.

• Journal of Life Science
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• v.20 no.11
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• pp.1589-1594
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• 2010

Glutaraldehyde was used to cross-link chitosan beads to immobilize the crude enzyme $\beta$-glucosidase from Exiguobacterium sp. DAU5. The conditions for preparing cross-linking chitosan beads and immobilization such as concentration of glutaradehyde, cross-linking time, immobilization pH and time were optimized. The chitosan beads were cross-linked with 1.5% glutaraldehyde for 1.5 hr. The immobilized $\beta$-glucosidase had an overall yield of 20% and specific activity of 5.22 U/g. The optimized pH and temperature were 9.0 and $55^{\circ}C$, respectively. More than 80% of its activity at pH 7.0-10.0, 80% at $40^{\circ}C$ for 2 hr and 48% at $50^{\circ}C$ for 1 hr, were retained. However, the immobilization product showed higher pH and thermal stabilities than free enzymes. It also showed high hydrolyzing activity on soybean isoflavone glycoside linkage. These results suggest the broad application prospects of immobilization enzymes.

• Journal of Plant Biology
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• v.27 no.3
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• pp.179-189
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• 1984

Durch vergleichende Untersuchungen von Ribes nigrum L. var. 'Rosenthals Langtraubige Schwarze' zwischen $prim\"{a}rem$ und $sekund\"{a}rem$ Jugendstadium (P.J. und S.J.) eine vertiefte Einsicht in die beiden zeitlich unterschielich langen $Entwicklungsabl\"{a}ufe$ zu bekommen und auf diese Weise bessere Ansatzpunke $f\"{u}r$ die Regulierung der $Bl\"{u}tc-nknospeninduktion$ zu gewinnen, war das Ziel vorliegenden Untersuchungen. Diese Untersuchungen $f\"{u}hrten$ zu den flogenden Ergebnissen: Die Dauer der Jugendphase von Ribes nigrum L. betrug bei den P.J.-Pflanzen ca. 7 Monate, bei den S.J.-Pflanzen ca. 5 Monate. Die $Bl\"{u}hreife$-(Ripeness to flower)-setzte bei den P.J.-Pflanzen erst beim 20. Nodium ein, bei den S.J.-Pflanzen bereits beim 5. Nodium. Das $f\"{u}hrte$ dazu, da${\beta}$ bei gleicher Nodienzahl die P.J.-Pflanzen weniger $Bl\"{u}te-nknospen$ angesetzt hatten als die S.J.-Pflanzen. Die erste $Bl\"{u}tenknospendifferenzierung$ setzte bei den P.J.-Pflanzen in der oberen Triebmitte etwa am 30. Nodium ein, beiden S.J.-Pflanzen bereits in der unteren Tricbmitte etwa am 20. Nodium. Bie den P.J.-Pflanzen waren die untersten 20. Nodien immer steril, $w\"{a}hrend$ bei den S.J.-Pflanzen $h\"{a}uflgsten$ an dem ersten Nodium $\"{u}ber$ der Basis fertil waren. In allen Versuchen hat sich gezeigt, da${\beta}$ der Wachstumsabschlu${\beta}$ -(Bildung einer Terminal Knospe)-, der bei Ribes nigrum L. durch Kurztag eingeleitet wird, bei den P.J.-Pflanzen langsammer als bei den S.J.-Pflanzen erfolgt. Dies $f\"{u}hrt$ dazu, da${\beta}$ die Pflanzen der $sekund\"{a}ren$ Jugendphase auf die photokybernetischen Stimulation empfindlicher reagieren als die der $prim\"{a}ren$ Jugendphase. Alle untersuchten Versuchsdaten $f\"{u}hren$ zu dem Schlu${\beta}$, da${\beta}$ die Wurzelgibberelline $(GA_n)$ keinen Einflu${\beta}$ auf die $Jugendsterilit\"{a}t$ ($Basissterilit\"{a}t$) haben. Aus den Untersuchungen geht hervor, da${\beta}$ die induktive Ma${\beta}$nahme zur Beschleunigung der $Bl\"{u}tenknospenbildung$ $f\"{u}r$ eine $Z\"{u}chtungsselektion$ erst dann eingesetzt werden sollen, wenn die P.J.-Pflanzen mehr als 20 Nodien ausgebildet haben.

• Journal of Environmental Science International
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• v.6 no.5
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• pp.531-539
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• 1997

Lead sorption performances by biomass of nonliving, dried marine brown algae Undaria phnaunda, Hlzikia hsyormls. and Sugassum fulvellum used as biosorbent materials were investigated. As the amount of biosorbent materials added was increased, the lead removal by biosorbent materials Increased but the lead biosorption capacities decreased. However, with increasing Initial lead concentration the lead biosorption capacities by the biosorbent materials Increased but lead removal efficiencies decreased. In the range of Initial lead concentration(Co) 10-500 mg/L the lead biosorption capacities and removal efficiencies by the biosorbent materials Increased with increasing pH. Among the biosorbent materials used in this study, the lead biosorption capacities decreased in the following sequence: U. plilnaunda > H. fusiformis > S. fulvellum. The lead biosorption by biosorbent materials were expressed by the Langmuir Isotherm better than the Freundlich Isotherm. The biosorption rate could be expressed by the first order reaction rate equation for initial lead concentration like that rad : 0.288Co for U. phanda, rad = 0.255Co for H. fusiformis, and rad : 0.161Co for S. fulvellum. Key words : Lead, biosorption, biosorbent, Undaria pinnatinda, Hiztkia fusiformis, Sargassum fulvellum, Langmuir isotherm, Freundlich isotherm, biosorption rate.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.1
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• pp.13-16
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• 2000

Simple procedures have been devised for purifying recombinant human interleukin-2 (hIL-2), which was expressed in Escberichia coli using sequences of glucagon molecules and enterokinase cleavage site as an N-terminus fusion partner. The insoluble aggregates of recombinant fusion protein produced in E. coli cytoplasm were easily dissolved by simple alkaline pH shift $(8\rightarrow12\rightarrow8)$. Following enterokinase cleavage, the recombinant hIL-2 was finally purified by one-step reversed-phase HPLC with high purity. The ease and high efficiency of this simple purification process seem to mainly result from the role of used glucagon fusion partner, which could be applied to the production of other therapeutically important proteins.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.568-571
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• 1999

Aspergillus oryzae U1521, which was a genetically engineered strain, produced 1,000,600 U per g . glucose of extracellular alkaline protease within 72 h in a submerged fermentation. However, the alkaline protease was not detected during the first 24 h. Northern blot analysis indicated that the enzyme synthesis was repressed at the transcriptional level during the lag period. Both catabolite repression and pH of the growth medium significantly affected the enzyme production. Use of this enzyme as a silver recovery agent from used X-ray film was confirmed by experiments in the shake-flask scale.

• Communications of the Korean Mathematical Society
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• v.39 no.3
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• pp.775-784
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• 2024

Let (X, m, 𝓗) be a hereditary m-space and γ : m → P(X) be an operation on m. A subset A of X is said to be γ𝓗-compact relative to X [3] if for every cover {U_𝛼 : 𝛼 ∈ 2206;} of A by m-open sets of X, there exists a finite subset ∆₀ of ∆ such that A ⧵ ∪{γ(U_𝛼) : 𝛼 ∈ ∆₀} ∈ 𝓗. In this paper, we define and investigate two kinds of strong forms of γ𝓗-compact relative to X.

• Journal of Pharmaceutical Investigation
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• v.5 no.3
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• pp.30-35
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• 1975

When the pH of the mixture containing oxytetracycline, $MgCl_26H_2O$ (2 : 1) and citric acid in aqueous solution is changed by adding monoethanolamine, some difference substances are produced. In the range of pH 8.5-9.3, the stable substance which exhibit U. V. max. absorption at 267.5-268 nm and 372.5 nm is produced. According to preparing method, the mixture of oxytetracycline. $MgCl_26H_2O$ (2 : 1) and citric acid in 75% propylene glycol aqueous solution are dissolved with monoethanolamine, and then, it is standed for a long time. An unknown substance is precipitated. It seems to be a compound containing $MgCl_26H_2O$, citric acid and monoethanolamine, but not oxytetracycline.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.4
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• pp.401-406
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• 1992

Antifungal substances against three plant pathogenic fungi, Phytophthora capsici, Phytophthora nicotianae var. parasitica and Rhizoctionaia solani were fractionated cultures of Streptomyces sp. A-2 strain isolated in Korean soils. Characterizations of active substances related with antagonistic effects were follows : 1. The excellent media which showed the transfer efficiency of antagonistic substances from Streptomyces sp. A-2 strain G.Y.B and B.H.I. among four that are glucose yeast broth (G.Y.B), $M\ddot{u}eller$, brain heart infusion(B.H.I.) and Czapek media. Active substances which were transfered into ethylacetate or left in residual aqueous phase did not lose antagonistic activity in spite of autoclavation. This indicated that bonds of these compounds were rigid enough to keep activity under such conditions. 2. Antagonistic substances were extracted according to adjustment of pH 3 or pH12 to 5 day-old B.H.I. broth cultures of Streptomyces sp. A-2 strain. Comparative analysis fluorescent bands on HPTLC to antagonsitic spectra against three phytopathogenic fungi indicated that major substances with antagonistic activity were extracted regardless of different pH adjustment to broth cultures. Since UV spectrum of these fractions scanned from 500nm to 200nm was similiar to that of polyene macrolide, major substances related with antagonistic activities were assumed to be polyene derivatives antibiotics.