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ON CONGRUENCES WITH THE TERMS OF THE SECOND ORDER SEQUENCES {Ukn} AND {Vkn}

  • KOPARAL, SIBEL;OMUR, Nese
    • Honam Mathematical Journal
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    • v.40 no.3
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    • pp.549-559
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    • 2018
  • In this paper, we consider the congruences involving harmonic numbers and the terms of the sequences {$U_{kn}$} and {$V_{kn}$}. For example, for an odd prime number p, $${\sum\limits_{i=1}^{p-1}}H_i{\frac{U_{k(i+m)}}{V^i_k}}{\equiv}{\frac{(-1)^kU_{k(m+1)}}{_pV^{p-1}_k}}(V^p_k-V_{kp})(mod\;p)$$, where $m{\in}{\mathbb{Z}}$ and $k{\in}{\mathbb{Z}}$ with $p{\nmid}V_k$.

A study of activity ratios of uranium isotope in the groundwater using liquid scintillation counter (액체섬광계수기를 이용한 지하수 내 우라늄 동위원소 측정법에 관한 연구)

  • Cho, Soo-Young;Song, Kyung-Sun;Lee, Kil-Yong;Yoon, Yoon-Yeol;Kim, Won-Baek;Ko, Kyung-Sok
    • Analytical Science and Technology
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    • v.25 no.2
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    • pp.146-151
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    • 2012
  • An analytical method was developed for the measurement of uranium isotope in ground water using the liquid scintillation counting technique. A LKB Wallac Quantulus 1220 liquid scintillation counter (LSC) equipped with pulse shape analyzer (PSA) and a solvent extraction method were used for the measurement of uranium isotope in ground water samples. The effect of solution volume on the extraction efficiency was evaluated for 100 to 1000 mL solutions using a NIST standard reference material (NIST SRM 4321C). The effect of groundwater pH on the extraction efficiency was also investigated for pH ranging from 0.5 to 10. It was found that the extraction efficiency had a strong dependence on pH showing a maximum at pH 2. In contrast, the effect of groundwater volume on the extraction efficiency was negligible in the range investigated. According to the method, the extraction efficiency of uranium isotopes was near 96% and the lower detection limit for uranium was 0.018 Bq/L with the counting time of 300 min. The result of this study was also verified by the conventional ICP-MS measurement. It is demonstrated that the suggested method is valuable to the determination of the optimum extraction and measurement conditions for uranium in ground water. The method was successfully applied to the ground water at four locations near the Daejeon province. It was found that the uranium content and the isotopic ratio of $^{234}U/^{238}U$ at the locations ranged 0.59~6.69 Bq/L and 0.72~1.40, respectively.

A Durational Study of Vowels Followed by Voiced or Voiceless Consonants (후행하는 유.무성자음에 의한 모음의 지속시간 고찰)

  • Park, Hee-Jung;Shin, Hey-Jung;Yang, Byung-Gon
    • Speech Sciences
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    • v.9 no.4
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    • pp.175-185
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    • 2002
  • The purpose of this study was to investigate the acoustic durations of Korean vowels followed by either voiced or voiceless consonants. Six healthy adult speakers (2 females and 4 males) recorded nonsense syllables in which voiced (/b, d, g/) or voiceless (/p', t', k', $p^{h},t^{h},k^{h}$) consonants follow three different vowels (/i, a, u/) embedded in a carrier phrase. Results showed that vowels preceding voiced consonants (e.g., haba) were significantly longer in duration than those preceding voiceless consonants (e.g., hiP' a or $hip^{h}a$). Also vowels were longer in duration when occurring before velar-stops than before bilabial-stop and dental-stops. Finally, the duration of the low vowel (/a/) was substantially longer than that of the high vowels (/i, u/). These findings may be applicable to speech synthesis or therapy.

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An Electrochemical Analysis on the Alloy Deposition of 80Ni-20Fe Permalloy Thin Film (80Ni-20Fe Permalloy 박모 동시석출 기구에 관한 전기화학적 고찰)

  • Lee, K. H.;Kang, Tak;Ra, H. Y.
    • Journal of the Korean institute of surface engineering
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    • v.15 no.1
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    • pp.11-18
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    • 1982
  • 80% Ni-Permalloy is soft magnetic material with high initial permeability and low magnetic coercive force Hc, and is used to computer memory cores and minirelays of communication e-ngineering. In this paper 80 Permalloy thin film on copper cathode was alloy-deposited from Watts so-lution contatining FeSO4$.$7H2O. The amount of FeSO4$.$7H2O in the solution, pH, temperature of the solution and plating current density were varied as parameters and the resulting comp-osition changes of deposited film were analyzed electrochemically with respect to the parame-ters. From the above procedure electroplating conditions for deposition of 80 Permalloy were est-ablished as following: 17-21 g/$\ell$ of FeSO4$.$7H2O in Watts solution, current density 1.0-2.0 Amp/dm2, pH 2.5-3.0 and temperature range of 50-60$^{\circ}C$.

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Characteristics of Thiamine Uptake by the BeWo Human Trophoblast Cell Line

  • Keating, Elisa;Lemos, Clara;Azevedo, Isabel;Martel, Fatima
    • BMB Reports
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    • v.39 no.4
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    • pp.383-393
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    • 2006
  • Little is known concerning the mechanisms responsible for the transplacental transfer of thiamine. So, the aim of this work was to characterize the placental uptake of thiamine from the maternal circulation, by determining the characteristics of $^3H$-thiamine uptake by a human trophoblast cell line (BeWo). Uptake of $^3H$-thiamine (50-100 nM) by BeWo cells was: 1) temperature-dependent and energy-independent; 2) pH-dependent (uptake increased as the extracellular medium pH decreased); 3) $Na^+$-dependent and $Cl^-$-independent; 4) not inhibited by the thiamine structural analogs amprolium, oxythiamine and thiamine pyrophosphate; 5) inhibited by the unrelated organic cations guanidine, N-methylnicotinamide, tetraethylammonium, clonidine and cimetidine; 6) inhibited by the organic cation serotonin, and by two selective inhibitors of the serotonin plasmalemmal transporter (hSERT), fluoxetine and desipramine. We conclude that $^3H$-thiamine uptake by BeWo cells seems to occur through a process distinct from thiamine transporter-1 (hThTr-1) and thiamine transporter-2 (hThTr-2). Rather, it seems to involve hSERT. Moreover, chronic (48 h) exposure of cells to caffeine ($1\;{\mu}M$) stimulated and chronic exposure to xanthohumol and iso-xanthohumol (1 and $0.1\;{\mu}M$, respectively) inhibited $^3H$-thiamine uptake, these effects being not mediated through modulation of the expression levels of either hThTr-1 or hSERT mRNA.

Increased Production of an Alkaline Protease from Bacillus clausii I-52 by Chromosomal Integration (Bacillus clausii I-52의 Chromosomal Integration에 의한 Alkaline Protease의 생산성 향상)

  • Joo, Han-Seung;Park, Dong-Chul;Choi, Jang-Won
    • Journal of agriculture & life science
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    • v.46 no.1
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    • pp.163-176
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    • 2012
  • TTo increase productivity of a strong extracellular alkaline protease (BCAP), stable strains of Bacillus clausii I-52 carrying another copy of BCAP gene in the chromosome were developed. Integrative vector, pHPS9-fuBCAP carrying BCAP promoter, ribosome binding site, signal sequence and active protease gene was constructed and transferred into B. clausii I-52, and integration of the constructed plasmid into chromosome was identified by PCR. An investigation was carried out on BCAP production by B. clausii I-52 and transformant C5 showing the highest relative activity of alkaline protease using submerged fermentation. Maximum enzyme activity was produced when cells were grown under the submerged fermentation conditions at $37^{\circ}C$ for 48 h with an aeration rate of 1 vvm and agitation rate of 650 rpm in a optimized medium (soybean meal 2%, wheat flour 1%, sodium citrate 0.5%, $K_2HPO_4$ 0.4%, $Na_2HPO_4$ 0.1%, NaCl 0.4%, $MgSO_47H_2O$ 0.01%, $FeSO_47H_2O$ 0.05%, liquid maltose 2.5%, $Na_2CO_3$ 0.6%). A protease yield of approximately 134,670U/ml was achieved using an optimized media, which show an increase of approximately 1.6-fold compared to that of non-transformant (83,960 U/ml). When the stability of transformant C5 was examined, the integrated plasmid pHPS9-fuBCAP was detected in the transformant after cultivation for 8 days, suggesting that it maintained stably in the chromosomal DNA of transformant C5.

Efficient Recovery of Lignocellulolytic Enzymes of Spent Mushroom Compost from Oyster Mushrooms, Pleurotus spp., and Potential Use in Dye Decolorization

  • Lim, Seon-Hwa;Lee, Yun-Hae;Kang, Hee-Wan
    • Mycobiology
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    • v.41 no.4
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    • pp.214-220
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    • 2013
  • This study was conducted in order to perform efficient extraction of lignocellulolytic enzymes amylase (EC 3.2.1.1), cellulase (EC 3.2.1.4), laccase (EC 1.10.3.2), and xylanase (EC 3.2.1.8) from spent mushroom compost (SMC) of Pleurotus ostreatus, P. eryngii, and P. cornucopiae. Optimal enzyme recovery was achieved when SMCs were extracted with 50 mM sodium citrate (pH 4.5) buffer at $4^{\circ}C$ for 2 hr. Amylase, cellulase, and xylanase activities showed high values in extracts from P. ostreatus SMC, with 2.97 U/g, 1.67 U/g, and 91.56 U/g, respectively, whereas laccase activity and filter paper degradation ability were highest in extracts from P. eryngii SMC, with values of 9.01 U/g and 0.21 U/g, respectively. Enzymatic activities varied according to the SMCs released from different mushroom farms. The synthetic dyes remazol brilliant blue R and Congo red were decolorized completely by the SMC extract of P. eryngii within 120 min, and the decolorization ability of the extract was comparable to that of 0.3 U of commercial laccase. In addition, laccase activity of the SMC extract from P. eryngii was compared to that of commercial enzymes or its industrial application in decolorization.

ON A CLASS OF OPERATORS RELATED TO PARANORMAL OPERATORS

  • Lee, Mi-Young;Lee, Sang-Hun
    • Journal of the Korean Mathematical Society
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    • v.44 no.1
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    • pp.25-34
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    • 2007
  • An operator $T{\in}L(H)$ is said to be p-paranormal if $$\parallel{\mid}T\mid^pU{\mid}T\mid^px{\parallel}x\parallel\geq\parallel{\mid}T\mid^px\parallel^2$$ for all $x{\in}H$ and p > 0, where $T=U{\mid}T\mid$ is the polar decomposition of T. It is easy that every 1-paranormal operator is paranormal, and every p-paranormal operator is paranormal for 0 < p < 1. In this note, we discuss some properties for p-paranormal operators.

ON THE STABILITY OF THE PEXIDER EQUATION IN SCHWARTZ DISTRIBUTIONS VIA HEAT KERNEL

  • Chung, Jae-Young;Chang, Jeong-Wook
    • Honam Mathematical Journal
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    • v.33 no.4
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    • pp.467-485
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    • 2011
  • We consider the Hyers-Ulam-Rassias stability problem $${\parallel}u{\circ}A-{\upsilon}{\circ}P_1-w{\circ}P_2{\parallel}{\leq}{\varepsilon}({\mid}x{\mid}^p+{\mid}y{\mid}^p)$$ for the Schwartz distributions u, ${\upsilon}$, w, which is a distributional version of the Pexider generalization of the Hyers-Ulam-Rassias stability problem ${\mid}(x+y)-g(x)-h(y){\mid}{\leq}{\varepsilon}({\mid}x{\mid}^p+{\mid}y{\mid}^p)$, x, $y{\in}\mathbb{R}^n$, for the functions f, g, h : $\mathbb{R}^n{\rightarrow}\mathbb{C}$.

Influence of Controlled- and Uncontrolled-pH Operations on Recombinant Phenylalanine Ammonia Lyase Production in Escherichia coli

  • Cui, Jian Dong;Zhao, Gui Xia;Zhang, Ya Nan;Jia, Shi Ru
    • Food Science and Biotechnology
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    • v.18 no.4
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    • pp.954-958
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    • 2009
  • Effects of controlled- and uncontrolled-pH operations on phenylalanine ammonia lyase (PAL) production by a recombinant Escherichia coli strain were investigated at uncontrolled-pH ($pH_{UC}$) and controlled-pH ($pH_C$) of 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, and 8.5 in bioreactor systems. The results showed that the recombinant PAL activity was improved significantly by controlled pH strategy. Among the $pH_C$ operations, the highest PAL activities were obtained under $pH_C$ 7.5 strategy where cell mass ($OD_{600\;nm}$) and PAL activity was 1.3 and 1.8 fold higher than those of $pH_{UC}$, respectively. The maximum PAL activity reached 123 U/g. The $pH_C$ 7.5 strategy made recombinant plasmid more stable and therefore allowed easier expression of PAL recombinant plasmid, which increased PAL production. It was indicated that the new approach (controlled-pH strategy) obtained in this work possessed a high potential for the industrial production of PAL, especially in the biosynthesis of L-phenylalanine.