• Title/Summary/Keyword: H.A.Z

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Clinical Dilemmas for the Diagnosis and Treatment of Helicobacter pylori Infection in Children: From Guideline to Practice

  • Susanne Jenneke Van Veen;Elvira Ingrid Levy;Koen Huysentruyt;Yvan Vandenplas
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.27 no.5
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    • pp.267-273
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    • 2024
  • Helicobacter pylori infection is often acquired in early childhood. While most infected children remain asymptomatic, H. pylori can cause chronic gastritis, gastric ulceration, and, in the long term, gastric cancer. This article aimed to review different diagnostic and treatment options and discuss the challenges associated with applying the current guidelines in the real world. Relevant articles published from 2015 to August 2023 in the English language in PubMed and Medline electronic databases were extracted using subject headings and keywords of interest to the topic. References of interest in the selected articles were also considered. Invasive and noninvasive diagnostic tests have advantages but also disadvantages and limitations according to the clinical setting and age of the child. Guidelines recommend not performing diagnostic testing in children with long-lasting or recurrent abdominal complaints or cases of a family history of severe disease caused by H. pylori. However, parents regularly consult with the explicit demand to test for H. pylori because of them or a close family member experiencing severe gastric disease caused by H. pylori. In some situations, it may be challenging for the healthcare professional to stick to evidence-based guidelines and not consider "patient-centered care," with the risk of putting a trustful relationship in danger. Physicians may find it challenging not to perform diagnostic tests for H. pylori and prescribe eradication treatment in specific clinical settings when maintaining a trusting patientphysician relationship by applying this "patient-centered care" method when evidence-based guidelines recommend differently.

Electron Impact Ionization Mass Spectra of 3-Substituted-2-hydroxy-4(3H)-quinazolinones

  • El Deen, I.M.;Abd El Fattah, M.E.
    • Bulletin of the Korean Chemical Society
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    • v.24 no.4
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    • pp.473-478
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    • 2003
  • 3-Amino-2-hydroxy-4(3H)-quinazolinone (3) was prepared via condensation of 1 with hydrazine hydrate. Treatment of 3 with appropriate acid in $POCl_3$, ethyl chloroacetate and activated olefinic compounds in DMF yielded the corresponding 3-(substituted)amino-2-hydroxy-4(3H)-quinazolinones 4, 5 and 6. The electron impact ionization mass spectra of compounds 3 and 4 show a weak molecular ion peak and a base peak of m/z 146 resulting from a cleavage fragmentation. The compounds 5 and 6 give a characteristic fragmentation pattern with a very stable fragment of benzopyrazolone (m/z 132).

STRONG LAWS OF LARGE NUMBERS FOR LINEAR PROCESSES GENERATED BY ASSOCIATED RANDOM VARIABLES IN A HILBERT SPACE

  • Ko, Mi-Hwa
    • Honam Mathematical Journal
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    • v.30 no.4
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    • pp.703-711
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    • 2008
  • Let ${{\xi}_k,k{\in}{\mathbb{Z}}}$ be an associated H-valued random variables with $E{\xi}_k$ = 0, $E{\parallel}{\xi}_k{\parallel}$ < ${\infty}$ and $E{\parallel}{\xi}_k{\parallel}^2$ < ${\infty}$ and {$a_k,k{\in}{\mathbb{Z}}$} a sequence of bounded linear operators such that ${\sum}^{\infty}_{j=0}j{\parallel}a_j{\parallel}_{L(H)}$ < ${\infty}$. We define the sationary Hilbert space process $X_k={\sum}^{\infty}_{j=0}a_j{\xi}_{k-j}$ and prove that $n^{-1}{\sum}^n_{k=1}X_k$ converges to zero.

The Characteristics Study on Detector for In-pipe Radioactive Contamination Counting

  • Seo B. K.;Kim G. H.;Jung Y. H.;Woo Z. H.;Oh W. Z.;Lee K. W.;Han M. J.
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.11b
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    • pp.269-279
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    • 2005
  • In this study, detectors characteristics for simultaneous counting of alpha and beta ray in a pipe were estimated. The detector were composed of thin ZnS(Ag) scintillator and plastic detector. The scintillator for counting alpha particles has been applied a polymer composite sheet, having a double layer structure of an inorganic scintillator ZnS(Ag) layer adhered onto a polymer sub-layer. The other for counting beta particles used a commercially available plastic scintillator. It was confirmed that the detectors were suitable for counting the in-pipe contamination.

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Effects of Aectic Acid-Water Solvents on the Organic Acid pulping of Wood (아세트산(酸)-물 용매계(溶媒系)에 의한 목재(木材)의 유기산(有機酸) 증해효과(蒸解效果))

  • Lee, Sun-Ho;Jo, Byoung-Muk
    • Journal of Forest and Environmental Science
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    • v.9 no.1
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    • pp.67-80
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    • 1993
  • There are a lot of serious problums associated with conventional pulping processes, such as kraft and sulfite. In order to tackle these difficulties, organic acid pulping of Populus tomentiglandulosa T. Lee and Pinus densiflora S. et Z. have been investigated as on alternative method. The acetic acid cooking of Populus tomentiglandulosa T. Lee achieved good delignification with pulp yields of 55-65% under almost all cooking conditions. In the acetic acid cooking of Pinus densiflora S. et Z., it was not cooked at a low temperature. The strength properties of the acetic acid pulps from Pinus tomentiglandulosa T. Lee showed the optimum with 95% acetic acid concentration at $185^{\circ}C$ maximum cooking temperature for 0.5hr cooking time. The strength properties of the acetic acid pulps from Pinus densiflora S. et Z. displayed excellent tear strength in comparison with those of the other softwoods. In the process of acetic acid cooking, glucose has been removed a little, but other sugars have been eliminated. The elemental compositions and $C_9$ formulas of acetosolv lignins from Populus tomentiglandulosa T. Lee were 63.88% carbon, 5.45% hydrogen and 30.67% oxygen and $C_9H_{9.15}O_{3.24}$ The elemental compositions and $C_9$ formulas of acetosolv lignins from Pinus densiflora S. et Z. were 61.85% carbon, 6.14% hydrogen and 32.01% oxygen and $C_9H_{9.15}O_{3.50}$ The Wt. av. MWT's of the acetosolv lignins from Pinus tomentiglandulosa T. Lee and Pinus densiflora S. et Z. were 731 and 725.

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Hydrogen Permselective Membrane using the Zirconia Coated Support (지르코니아 코팅 지지체를 이용한 수소분리막)

  • Choi, Ho-Sang;Ryu, Cheol-Hwi;Hwang, Gab-Jin
    • Membrane Journal
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    • v.20 no.3
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    • pp.210-216
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    • 2010
  • The hydrogen permselective membrane were prepared by chemical vapor deposition (CVD) aiming at the applications to hydrogen iodide decomposition in the thermochemical IS process, and it was evaluated for the possibility as a separation membrane. An electron probe X-ray microanalyzer (EPMA) and SEM picture were used to analyze the morphology and structure of the prepared membranes. It was confirmed that Zr-Si-O layer exist in the surface of the prepared membrane using zirconia coated support. Single-component permeance to $H_2$ and $N_2$ were measured at $300{\sim}600^{\circ}C$. Hydrogen permeance through the Z-1 membrane at a permeation temperature of $600^{\circ}C$ was about $1{\times}10^{-7}\;mol{\cdot}Pa^{-1}{\cdot}m^{-2}{\cdot}s^{-1}$. The selectivities of $H_2/N_2$ at $600^{\circ}C$ were 5.0 and 5.75 for Z-1 and Z-2 membrane, respectively.

Synthesis of an Aspartame Precursor Using Thermolysin in Organic Two-Phase System (유기용매 이상계에서 Thermolysin에 의한 아스파탐 전구체 생산)

  • 이인영;안경섭;이선복
    • Microbiology and Biotechnology Letters
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    • v.20 no.1
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    • pp.61-67
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    • 1992
  • The synthesis of N-benzyloxycarbonyl-L-aspartyl-L-phenylalanine methyl ester(ZAPM), a precursor of aspartame, from N-benzyloxycarbonyl-L-aspartic acid(Z-Asp) and L-phenylalanine methyl ester hydrochloride(L-PM-HCl) was investigated in ethylacetate-MES buffer two-phase system using thermolysin. In organic two-phase system, the degree of spontaneous hydrolysis of L-PM. HCl was significantly reduced with increasing the volume ratio of organic to aqueous phase. Stability of thermolysin in organic two-phase system was found to be higher than that in MES buffer solution. More than 90% of initial enzyme activity was maintained after 10 days of incubation in case that the volume of organic phase was equal to that of buffer phase, while the half life of thermolysin was about 2 days in aqueous buffer solution. The results of partitioning of substrates and product in organic two-phase system showed that the difference in partition coefficients between substrates and product was maximum at pH 5.5. The optimal pH for 2-APM synthesis in organic two-phase system was found to be 5.5-5.8, which is consistent with the value expected from the partition experiments. As the concentration of substrates was increased the conversion yield of Z-APM was increased with concomitant reduction of L-PMqHC1 hydrolysis. In case that the concentration of L-PM-HCl and Z-Asp were 160 mM and 80 mM respectively, the conversion yield of Z-APM reached 90% after 28 hrs of reaction. The yield obtained at different volume ratio of organic phase compares well with the predicted equilibrium constant in biphasic system.

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Infinite 1-D and 3-D Nets with Two Different Zinc and Terbium Coordination Polymers.

  • 민동원;이연경;이순원
    • Proceedings of the Korea Crystallographic Association Conference
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    • 2002.11a
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    • pp.31-31
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    • 2002
  • The hydrothermal reaction of Zn(NO₃)₂6H₂O with benzene-1,3-dicarboxylic acid (or isophthalic acid, 1,3-BDCH₂) and pyridine led to the formation of a 1-dimensional coordination polymer with the empirical formula of [Zn₄(1,3-BDC)₃(Py)₂(O/sup 2-/)] (1). On the other hand, the hydrothermal reaction of Tb(NO₃)₃5H₂O with benzene-1,3-dicarboxylic acid (or isophthalic acid, 1,3-BDCH₂) and pyridine gave a 3-D compound [Tb₃(1,3-BDC)₂(H₂O₃] (2). The structures of both compounds have been determined by X-ray diffraction. 1 crystallizes in the monoclinlc space group P2₁/n, a = 10.344(3) Å, b = 18.030(3) Å, c = 18.033(3) Å, = 90.46(2)°, V = 3363.1(13) ,ų, Z = 4. 2 crystallizes in the monoclinic space group C2/n, a = 22.253(5) Å, b = 18.672(4) Å, c = 11.5812 Å, = 101.40(2)°, V = 4717.3(21) ų, Z = 8.

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A Parallel Operation System of the Z-Source Active Power Filter with Fuel Cells System (연료전지 Z-소스 능동전력필터의 병렬운전 시스템)

  • Oum, J.H.;Jung, Y.G.;Lim, Y.C.
    • Proceedings of the KIEE Conference
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    • 2006.04b
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    • pp.372-375
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    • 2006
  • This paper proposes a parallel operation system of the Z-source active power filter using one fuel cells(FC) system. The proposed system is composed of two Z-source inverters operating in parallel only one PEM(Polymer Electrolyte Membrane)FC system. Also, as the control algorithm of the active power filter, a single phase P-Q theory and PI control are adopted. The effectiveness of the proposed the system is verified by the PSIM simulation in the steady state and the transient state.

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