• 산업경영시스템학회지
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• 제32권2호
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• pp.57-65
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• 2009

In continuous review inventory model, (${\varrho}$, ${\gamma}$) system, order quantity(${\varrho}$) and reorder point(${\gamma}$) should be determined to calculate inventory-related cost that consists of setup, holding, and penalty costs. The procedure to obtain the exact value of ${\varrho}$ and ${\gamma}$ is complex. In this paper, a regression analysis is proposed to get the approximate inventory-related cost without the determination of ${\varrho}$ and ${\gamma}$ in the case that the standard deviation(${\sigma}$) of the lead time demand is small or that the mean(${\mu}$) of the lead time demand is proportional to ${\sigma}$. To save inventory-related cost, central warehouses with (${\varrho}$, ${\gamma}$) system can be built. Central warehouse can provide some stores with products with the consideration of the tradeoff between inventory-related cost and transportation cost. The number and the location of central warehouses to cover all the stores are determined by a regression-based approach. The performance of the proposed approach is tested by using some computational experiments.

• Nuclear Engineering and Technology
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• 제55권11호
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• pp.4057-4065
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• 2023

Organic scintillators are widely used for neutron/gamma detection. Pulse shape discrimination algorithms have been commonly used to discriminate the detected radiations. These algorithms have several limits, in particular with plastic scintillator which has lower discrimination ability, compared to liquid scintillator. Recently, machine learning (ML) models have been explored to enhance discrimination performance. Nevertheless, obtaining an accurate ML model or evaluating any discrimination approach requires a reference neutron dataset. The preparation of this is challenging because neutron sources are also gamma-ray emitters. Therefore, this paper proposes a pipeline to prepare clean labeled neutron/gamma datasets acquired by an organic scintillator. The method is mainly based on a Time of Flight setup and Tail-to-Total integral ratio (TTT_ratio) discrimination algorithm. In the presented case, EJ276 plastic scintillator and ²⁵²Cf source were used to implement the acquisition chain. The results showed that this process can identify and remove mislabeled samples in the entire ToF spectrum, including those that contribute to peak values. Furthermore, the process cleans ToF dataset from pile-up events, which can significantly impact experimental results and the conclusions extracted from them.

• Asian Pacific Journal of Cancer Prevention
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• 제13권11호
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• pp.5875-5878
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• 2012

Background: Peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) is a ligand dependent transcription factor involved in various processes, including carcinogenesis. We aimed to investigate any possible association of the $PPAR{\gamma}$ Pro12Ala (rs1801282) polymorphism with risk of developing gastric cancer (GC). Patients and Methods: A hospital based case control study was designed covering 50 patients with GC and 120 healthy controls. The frequencies of $PPAR{\gamma}$ Pro12Ala (rs1801282) were determined using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Results: The Ala12 allele of the $PPAR{\gamma}$ Pro12Ala G gene was associated with a 1.95 fold increased risk of GC development (p: 0.022; 95% CI: 1.58-2.40). Subgroup analyses showed that the same allele was also associated with metastasis (p: 0.000; OR:4.09; 95%CI:2.273-7.368) and differentiation (p: 0.004; OR:1.95; 95%CI:1.335-2.875) in patients with GC. Conclusion: This study suggests that the $PPAR{\gamma}$ Pro12Ala G (Ala12) allele might be associated with development, differentiation and metastatic process of GC in the Turkish population. Further studies conducted in larger study groups and in different ethnic populations will be needed to clarify the exact role of the $PPAR{\gamma}$ Pro12Ala polymorphism in GC.

• Biomolecules & Therapeutics
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• 제25권6호
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• pp.609-617
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• 2017

Pancreatic cancer is one of the most lethal and aggressive cancers in the world. However, no effective treatment is currently available for pancreatic cancer. The objective of this study was to determine the anti-pancreatic cancer effect of ${\alpha}$-mangostin (${\alpha}M$) and ${\gamma}$-mangostin (${\gamma}M$) extracted from the pericarp of Garcinia mangostana L.. Both ${\alpha}$M and ${\gamma}M$ reduced the viability of pancreatic cancer cells MIA PaCa-2 and PANC-1 in a dose-dependent manner. These compounds induced apoptosis by increasing c-PARP and c-Caspase 3 levels. They also induced autophagy by increasing levels of microtubule-associated protein 1A/1B light chain 3B (LC3II) in both cell lines while decreasing sequestosome 1 (p62) in MIA PaCa-2. Both ${\alpha}$M and ${\gamma}M$ induced autophagy through increasing phosphorylation levels of AMP-activated protein kinase (p-AMPK) and p38-mitogen activated protein kinase (p-p38) while decreasing phosphorylation level of mammalian target of rapamycin complex 1 (p-mTOR). Of various microRNAs (miRNA), miR-18a was found to be a putative regulatory miRNA for autophagy induced by ${\alpha}$M or ${\gamma}M$. In combination with gemcitabine, a compound frequently used in pancreatic cancer treatment, ${\alpha}$M and ${\gamma}M$ showed synergistic anti-cancer effects in MIA PaCa-2. Collectively, these results suggest that ${\alpha}$M and ${\gamma}M$ can induce apoptosis and autophagy in pancreatic cancer cells and that their anti-cancer effect is likely to be associated with miR-18a. In conclusion, ${\alpha}$M and ${\gamma}M$ might be used as a potential new therapy for pancreatic cancer.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.345-345
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• 2006

It is well known that poly(glutamate)s with long n-alkyl side chains form thermotropic liquid crystalline state by melting of the side-chain crystallites and also poly(glutamate)s such as poly(${\gamma}-benzyl\;L-glutamate$ )(PBLG), poly(${\gamma}-n-alkyl\;L-glutamate$), etc. in solvent form the isotropic, biphasic and liquid crystalline phases which contains cholesteric and columnar liquid crystalline forms depending on the polypeptide concentration. Although there is no diffusion study for PBLG in liquid crystalline state, because it is difficult to observed $^{1}H$ spectrum of PBLG in liquid crystalline state for its very short $^{1}H\;T_{2}$. In this study, the diffusional behavior of rodlike PBLG in concentrated solution is successfully elucidated as studied by the field-gradient $^{1}H$ NMR methods.

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 NEW STRATEGY FOR DRUG DEVELOPMENT IN POST-GENOMIC ERA(대한약학회)
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• pp.147.1-147.1
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• 2000

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.488-488
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• 2015

Intermittent streamflow is common phenomenon in arid and semi-arid regions. To manage water resources of intermittent streamflows, stochactic simulation data is essential; however the seasonally stochastic modeling for intermittent streamflow is a difficult task. In this study, using the periodic Markov chain model, we simulate intermittent monthly streamflow for occurrence and the periodic gamma autoregressive and copula models for amount. The copula models were tested in a previous study for the simulation of yearly streamflow, resulting in successful replication of the key and operational statistics of historical data; however, the copula models have never been tested on a monthly time scale. The intermittent models were applied to the Colorado River system in the present study. A few drawbacks of the PGAR model were identified, such as significant underestimation of minimum values on an aggregated yearly time scale and restrictions of the parameter boundaries. Conversely, the copula models do not present such drawbacks but show feasible reproduction of key and operational statistics. We concluded that the periodic Markov chain based the copula models is a practicable method to simulate intermittent monthly streamflow time series.

• Tuberculosis and Respiratory Diseases
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• 제57권1호
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• pp.25-31
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• 2004

연구배경 : IFN-${\gamma}$는 결핵균에 대한 숙주의 면역학적 방어기전에서 핵심적인 역할을 한다. 그러므로 결핵균 항원들이 IFN-${\gamma}$ 유전자 발현에 미치는 영향을 알아보는 것은 결핵균에 대한 숙주의 방어기전을 밝히고 이를 이용한 백신의 개발에 이용될 수 있을 것이다. 방 법 : 결핵성 흉막염 환자의 흉수에서 얻은 림프구 배양액에 결핵균(H37Rv), PPD, Ag85B, man-LAM, ara-LAM을 첨가하여 자극한 후 림프구의 IFN-${\gamma}$ mRNA의 발현 정도를 역전사 중합효소연쇄반응을 이용하여 비교하였다. 결 과 : 1) 결핵균(H37Rv)이 결핵성 흉수 림프구의 IFN-${\gamma}$ mRNA의 발현을 증가시켰다. 2) 결핵균 항원 중 PPD와 Ag85B는 결핵성 흉수 림프구의 IFN-${\gamma}$ mRNA의 발현을 증가시켰지만 man-LAM은 결핵성 흉수 림프구의 IFN-${\gamma}$ mRNA의 발현을 억제시켰다. 3) LAM 중에서 man-LAM은 용량이 증가함에 따라 결핵성 흉수 림프구의 IFN-${\gamma}$ mRNA의 발현의 억제 정도가 증가하였지만 ara-LAM의 경우 이와 같은 현상이 관찰되지 않았다. 결 론 : 결핵성 흉수 림프구의IFN-${\gamma}$ mRNA의 발현은 PPD와 Ag85B의 자극에 의해 항진되지만 man-LAM의 자극에 의해서는 억제되었다.

• 대한화학회지
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• 제26권6호
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• pp.421-426
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• 1982

자유 라디칼 개시제에 의한 인산디에틸이소프로페닐(DEIPA)과 초산비닐(VAc) 및 아크릴로니트릴(An)의 혼성중합 연구를 행하여 단위체 반응성비를 얻었다. 개시제로는 과산화벤조일을 사용하였으며 중합온도는 $60^{\cric}C$이었다. 단위체 반응성비는${\gamma}_1$(VAc) = 1.56, ${\gamma}_2$(DEIPA) = 0.44: ${\gamma}_1$(AN) = 15.2, ${\gamma}_2$(DEIPA) = 0.031이었다. 이 값으로부터 DEIPA의 Alfrey-Price 상수 Q=0.015, e=0.39 및 Q=0.014, e=0.34를 얻었으며${\alpha}$ 위치에 있는 메틸기가 반응성을 감소시킴을 알았다. 공중합체중 DEIPA의 함량이 증가함에 따라 공중합체의 고유점성도 및 수평균 분자량이 감소함도 알았다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권9호
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• pp.5421-5425
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• 2013

Background: To assess the antioxidant effects of gamma-oryzanol on human prostate cancer cells. Materials and Methods: Cytotoxic activity of gamma-oryzanol on human DU145 and PC3 prostate cancer cells was determined by proliferation assay using 3-(4, 5-dimethylthiazol, 2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) reagent. mRNA levels of genes involved in the intracellular antioxidant system, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GSR) were determined by reverse transcription-polymerase chain reaction (RT-PCR). Cancer cell lysates were used to measure lipid peroxidation using thiobarbituric acid reactive substance (TBARS). Glutathione contents of the cell lysates were estimated by the reaction between sulfhydryl group of 5, 5'-dithio (bis) nitrobenzoic acid (DTNB) to produce a yellow-color of 5-thio-2-nitrobenzoic acid using colorimetric assay. Catalase activity was also analysed by examining peroxidative function. Protein concentration was estimated by Bradford's assay. Results: All concentrations of gamma-oryzanol, 0.1-2.0mg/ml, significantly inhibited cell growth in a dose- and time-dependent fashion in both prostate cancer cell lines, DU145 and PC3. Gene expression of catalase in DU145 and PC3 exposed to gamma-orizanol at 0.5mg/ml for 14 days was down regulated, while mRNA of GPX was also down regulated in PC3. The MDA and glutathione levels including catalase activity in the cell lysates of DU145 and PC3 treated with gamma-oryzanol 0.1 and 0.5mg/ml were generally decreased. Conclusions: This study highlighted effects of gamma-oryzanol via the down-regulation of antioxidant genes, catalase and GPX, not cytotoxic roles. This might be interesting for adjuvant chemotherapy to make prostate cancer cells more sensitive to free radicals. It might be useful for the reduction of cytotoxic agents and cancer chemoprevention.