• Title/Summary/Keyword: Activity Limits

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The problems of spatial modernization of the economy and new approaches to way out from crisis: Kazakhstan's experience

  • Kireyeva, Anel A.;Nurlanova, Nailya K.
    • Journal of Distribution Science
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    • v.11 no.3
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    • pp.39-48
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    • 2013
  • Purpose - This study aims to analyze the main problems of spatial modernization of the economy, and to develop new approaches to way out from crisis, to accelerate of innovations process from the cities-centers to the underdeveloped regions. Research design, data, methodology - The application of scientific methods in this research will allow to systematize the available data, from both a theoretical and empirical perspective. The study employs the method of ranking regions, the rate of innovation activity and comparative evaluation of R&D indicator. In addition, the authors proposed the method of modeling of innovation diffusion in the regions. Results - This study confirms that the need help for the underdeveloped regions, but we should clearly understand the limits of opportunities and to choose the right mechanisms. Further, this study shows it's important to maintain the regions with high innovation activity, as they are growth poles, which are play the role of translator's innovations to the periphery. Conclusions - According to the results of this theoretical and empirical study proved that modernization of the economy is realized faster in the regions with the best conditions for the diffusion of innovations, the higher the concentration of the population, a more developed infrastructure and reduced of administrative barriers.

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STRUCTURE, SYNTHESIS, AND BIOLOGICAL FUNCTION OF NATURAL PRODUCTS IN DEER ANTLER AND THEIR DERIVATIVES

  • Kim, So-Yeon;Jhon, Gil-Ja;Lee, Yoon-Jin;Cho, So-Hye;Han, So-Yeop
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.126-126
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    • 1998
  • Studies on natural products are of great interest, due to the limits in development of synthesized medicine and its side effects. Deer antler is the most popular cure-all type drug among Asian folk medicines. In this study, we newly isolated the biologically active components from chloroform extract and 70% ethanol extract of deer antler, and analyzed their structures. First, the structure of monoacetyldiglyceride in deer antler was identified. To investigate the structure-activity relationship of monoacetyldiglycerides, we synthesized diverse substituted glycerides from glycerol, and confirmed their structures by spectroscopic methods. Among seven structurally-interesting compounds tested in this study, compound 1,2,3,5, and 6 showed activity toward [Ca$\^$2+/]$\_$i/ increase in fura-2 loaded rat pancreatic acinar cells. Second, 70% ethanol extract of deer antler stimulated insulin release from rat pancreatic islets. We found the most effective fraction was CN-Es-8 in 70% ethanol extract, and it increased intracellular Ca$\^$2+/ concentration in pancreatic ${\beta}$-cell.

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Antioxidant Activity of NADH and Its Analogue - An In Vitro Study

  • Olek, Robert Antoni;Ziolkowski, Wieslaw;Kaczor, Jan Jacek;Greci, Lucedio;Popinigis, Jerzy;Antosiewicz, Jedrzej
    • BMB Reports
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    • v.37 no.4
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    • pp.416-421
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    • 2004
  • The antioxidant activities of NADH and of its analogue, 1,4-dihydro-2,6-dimethyl-3,5-dicarbethoxy-pyridine ($PyH_2$), were evaluated in vitro. NADH was found to be oxidized by the peroxyl radical derived from 2,2-azobis-(2-amidinopropane) dihydrochloride (AAPH) decomposition, in a pH-dependent manner. Both NADH and $PyH_2$ inhibited the peroxidation of egg yolk lecithin (EYL) liposomes, although $PyH_2$ was more effective than NADH when 2,2'-azobis-4-methoxy-2,4-dimethyl-valeronitrile (methoxy-AMVN) was employed to induce EYL liposome peroxidation. The antioxidant activities of NADH and $PyH_2$ were also evaluated by measuring their influences on 1,3-diphenylisobenzofuran (DPBF) fluorescence decay in the presence of peroxyl radicals. NADH and $PyH_2$ were much more effective at inhibiting DPBF quenching in Triton X-100 micelles than in liposomes. These results indicate that NADH can inhibit lipid peroxidation despite being hydrophilic. Nevertheless, membrane penetration is an important factor and limits its antioxidant activity.

Autoxidation Core@Anti-Oxidation Shell Structure as a Catalyst Support for Oxygen Reduction Reaction in Proton Exchange Membrane Fuel Cell

  • Heo, Yong-Kang;Lee, Seung-Hyo
    • Corrosion Science and Technology
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    • v.21 no.5
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    • pp.412-417
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    • 2022
  • Proton exchange membrane fuel cells (PEMFCs) provide zero emission power sources for electric vehicles and portable electronic devices. Although significant progresses for the widespread application of electrochemical energy technology have been achieved, some drawbacks such as catalytic activity, durability, and high cost of catalysts still remain. Pt-based catalysts are regarded as the most efficient catalysts for sluggish kinetics of oxygen reduction reaction (ORR). However, their prohibitive cost limits the commercialization of PEMFCs. Therefore, we proposed a NiCo@Au core shell structure as Pt-free ORR electrocatalyst in PEMFCs. NiCo alloy was synthesized as core to introduce ionization tendency and autoxidation reaction. Au as a shell was synthesized to prevent oxidation of core NiCo and increase catalytic activity for ORR. Herein, we report the synthesis, characterization, electrochemical properties, and PEMFCs performance of the novel NiCo@Au core-shell as a catalyst for ORR in PEMFCs application. Based on results of this study, possible mechanism for catalytic of autoxidation core@anti-oxidation shell in PEMFCs is suggested.

Assessment of occupational radiation exposure of NORM scales residues from oil and gas production

  • EL Hadji Mamadou Fall;Abderrazak Nechaf;Modou Niang;Nadia Rabia;Fatou Ndoye;Ndeye Arame Boye Faye
    • Nuclear Engineering and Technology
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    • v.55 no.5
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    • pp.1757-1762
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    • 2023
  • Radiological hazards from external exposure of naturally occurring radioactive materials (NORM) scales residues, generated during the extraction process of oil and gas production in southern Algeria, are evaluated. The activity concentrations of 226Ra, 232Th, and 40K were measured using high-purity gamma-ray spectrometry (GeHP). Mean activity concentration of 226Ra, 232Th and 40K, found in scale samples are 4082 ± 41, 1060 ± 38 and 568 ± 36 Bq kg-1, respectively. Radiological hazard parameters, such as radium equivalent (Raeq), external and internal hazard indices (Hex, Hin), and gamma index (Iγ) are also evaluated. All hazard parameter values were greater than the permissible and recommended limits and the average annual effective dose value exceeded the dose constraint (0.3 mSv y-1). However, for occasionally exposed workers, the dose rate of 0.65 ± 0.02 mSv y-1 is lower than recommended limit of 1 mSv y-1 for public.

Positive Regulator, a Rice C3H2C3-type RING Finger Protein H2-3(OsRFPH2-3), in Response to Salt Stress

  • Min Seok Choi;Cheol Seong Jang
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2023.04a
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    • pp.156-156
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    • 2023
  • Salinity is a major abiotic stress that limits rice productivity in many regions of the world. In order to develop salt stress tolerant rice plants, genetic engineering is a promising approach. We characterized the molecular function of rice C3H2C3 as a really interesting new gene (RING). Oryza sativa RING finger protein H2-3 (OsRFPH2-3) was highly expressed in 100 mM NaCl. To identify the localization of OsRFPH2-3, we fused vectors that include C-terminal GFP protein (35S;;OsRFPH2-3-GFP). OsRFPH2-3 was expressed in the nucleus in rice protoplasts. An in vitro ubiquitin assay demonstrated that OsRFPH2-3 possessed E3-ubiquitin ligase activity. However, the mutated OsRFPH2-3 were not possessed any E3-ubiquitin ligase activity. Under salinity conditions, OsRFPH2-3-overexpressing plants exhibited higher chlorophyll, proline, SOD, POD, CAT, and soluble sugar contents and lower H2O2 accumulation than wild-type plants, supporting transgenic plants with enhanced salinity tolerance phenotypes. OsRFPH2-3-overexpressing plants exhibited low Na+ accumulation and Na+/K+ ratios in their roots. Theses results suggest that overexpression of OsRFPH2-3 can make plant insensitivity about salinity conditions.

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Circadian Rhythms Characteristics of Nurses Providing Direct Patient Care: An Observational Study

  • Ilknur Dolu;Serap Acikgoz;Ali Riza Demirbas;Erdem Karabulut
    • Safety and Health at Work
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    • v.15 no.1
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    • pp.102-109
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    • 2024
  • Background: In today's modern world, longer working hours, shift work, and working at night have become major causes of the disruption of our natural circadian rhythms. This study aimed to investigate the effects of the type of shift work (rotating vs. fixed day), duty period (on-duty vs. off-duty), and working period within each shift (nighttime vs. daytime) on the circadian rhythm characteristics of nurses who provide direct patient care. Methods: This cross-sectional study used a purposive sampling method. Cosinor analysis was applied to analyze the actigraphy data of nurses providing direct patient care for seven consecutive days. The linear mixed effects model was then used to determine any variances between shift type, duty period, and working period within each shift for the nurses. Results: The mesor value did not differ according to nurses' shift type, duty period, and working period within each shift. The amplitude was statistically higher in on-duty nurses and in daytime working hours. The acrophase was significantly delayed in nighttime working hours. As well as nurses in rotating shift had experience. Conclusion: Our findings revealed that the peak activity of nurses occurs significantly later at night while working and nurses working during nighttime hours may have a weaker or less distinct circadian rhythm. Thus, this study suggests that limits be placed on the number of rotating nighttime shifts for nurses.

SUPEROXIDE DISMUTASE - AND CATALASE - ACTIVITY IN BLOOD PLASMA AND RED BLOOD CELLS IN PERIODONTITIS (치주염 환자의 혈장과 적혈구내 S.O.D와 Catalase 활성도에 관한 연구)

  • Hwang, Seung-Hwan;Kim, Byung-Ok;Han, Kyung-Yoon
    • Journal of Periodontal and Implant Science
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    • v.25 no.1
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    • pp.167-178
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    • 1995
  • It has been believed that the increased release of free oxygen radicals and their tissue damaging potency might be a contributing factor in the pathogenesis of periodontal disease. Antioxidant enzymes such as superoxide dismutase(SOD) and catalase can protect the tissue damage from the free oxygen radicals($O_2^-,H_2O_2$, and $OH^-$). In order to investigate the SOD- and catalase - activity in the blood plasma and red blood cells(RBCs) of the patients with perodontitis, 19 male periodontitis patients($25{\sim}35$ years old) who had good general health, more than 10 teeth with severely inflamed gingiva, attachment loss more than 6mm and bone loss were selected as periodontitis group, and 13 male volunteers($22{\sim}29$ years old) with good general and periodontal health were selected as normal group. After blood plasma and RBC were separated from peripheral blood of 2ml collected from antecubital vein of each subject, SOD- activity in blood plasma and RBCs was measured by the same method that Paoletti et al. did, and catalase - activity in RBC was measured by the same method that Beers et al, did. The difference of SOD- and catalase - activity between the normal and the periodontitis groups was statistically analyzed by Student t-test with SPSS/PC program.The results were as follows : 1. SOD activity in blood plasma was significantly lower in the periodontitis group($1.986{\pm}0.893$) than in the normal group($3.324{\pm}1.044$)(p<0.05). 2. There was no statistical significance in the difference of SOD- activity in RBCs between the periodontitis group($7.753{\pm}3.206$) and the normal group($8.116{\pm}1.192$)(p$242.8{\pm}45.6$) than in the normal group($280.2{\pm}32.6$)(p

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Exploratory Study on Causality of Expansion Strategy into Emerging Market: Systems Thinking Approach (이머징 마켓 진출 전략의 인과관계에 대한 탐색적 연구: 시스템 사고에 의한 접근)

  • Chung, Chang-Kwon;Lee, Dong-Hyun
    • Korean System Dynamics Review
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    • v.13 no.3
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    • pp.67-98
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    • 2012
  • This study suggests a set of Causal Loop Diagram (CLD) of Causality Mechanism which integrates the matter of characteristics of emerging market and its expansion strategies. In order to make CLD more objective, all causalities are articulated from recent 55 studies (2000~2012) of SSCI Top Journals. This approach is valuable in that it is a first try to draw all the causalities from rigorous literature review regarding emerging market strategy. The 5 CLDs will show and clarify the strategies of how to expand into emerging market for MNCs. In sum, political activity and institutional void is a critical factor related to characteristics of emerging market, and CSV and cultural distance should be considered as a leverage point. For all this study's contribution to clarify the causality of emerging market strategies with abundant literature review, the study has its limits in integrating and testing CLD.

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Hippo Signaling Circuit and Divergent Tissue Growth in Mammalian Eye

  • Moon, Kyeong Hwan;Kim, Jin Woo
    • Molecules and Cells
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    • v.41 no.4
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    • pp.257-263
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    • 2018
  • Vertebrate organ development is accompanied by demarcation of tissue compartments, which grow coordinately with their neighbors. Hence, perturbing the coordinative growth of neighboring tissue compartments frequently results in organ malformation. The growth of tissue compartments is regulated by multiple intercellular and intracellular signaling pathways, including the Hippo signaling pathway that limits the growth of various organs. In the optic neuroepithelial continuum, which is partitioned into the retina, retinal pigment epithelium (RPE) and ciliary margin (CM) during eye development, the Hippo signaling activity operates differentially, as it does in many tissues. In this review, we summarize recent studies that have explored the relationship between the Hippo signaling pathway and growth of optic neuroepithelial compartments. We will focus particularly on the roles of a tumor suppressor, neurofibromin 2 (NF2), whose expression is not only dependent on compartment-specific transcription factors, but is also subject to regulation by a Hippo-Yap feedback signaling circuit.