Assessment and comparison of three different air quality indices in China

Youping Li,Ya Tang,Zhongyu Fan,Hong Zhou,Zhengzheng Yang 대한환경공학회 2018 Environmental Engineering Research Vol.23 No.1

Air pollution index (API) is used in Mainland China and includes only SO₂, NO₂ and PM10. In 2016, air quality index (AQI) replaced API. AQI contains three more air pollutants (CO, O₃ and PM2.5). Both the indices emphasize on the effect of a single pollutant, whereas the contributions of all other pollutants are ignored. Therefore, in the present work, a novel air quality index (NAQI), which emphasizes on all air pollutants, has been introduced for the first time. The results showed that there were 19 d (5.2%) in API, 28 d (7.7%) in AQI and 183 d (50.1%) in NAQI when the indices were more than 100. In API, PM10 and SO₂ were regarded as the primary pollutants, whereas all five air pollutants in AQI were regarded as primary. Furthermore, four air pollutants (other than the CO) in NAQI were regarded as primary pollutants. PM10, as being the primary pollutant, contributed greatly in these air quality indices, and accounted for 51.2% (API), 37.0% (AQI) and 52.6% (NAQI). The results also showed that particulate matter pollution was significantly high in Luzhou, where stricter pollution control measures should be implemented.

Magnolol Inhibits iNOS, p38 Kinase, and NF-κB/Rel in Murine Macrophages

Li Mei Hong,Chang In-Youp,Youn Ho-Jin,Jang Dae-Sik,Kim Jin-Sook,Jeon Young-Jin Korean Society of ToxicologyKorea Environmental Mu 2006 Toxicological Research Vol.22 No.3

We demonstrate that magnolol, a hydroxylated biphenyl compound isolated from Magnolia officinalis, inhibits LPS-induced expression of iNOS gene in RAW 264.7 cells(murine macrophage cell line). Treatment of RAW 264.7 cells with magnolol inhibited LPS-stimulated nitric oxide production in a dose-related manner. RT-PCR analysis showed that the decrease of NO was due to the inhibition of iNOS gene expression. Western immunoblot analysis of phosphorylate p38 kinase showed magnolol significantly inhibited the phosphorylation of p38 kinase which is important in the regulation of iNOS gene expression. The specific p38 inhibiter SB203580 abrogated the LPS-induced NO generation and iNOS expression, whereas the selective MEK-1 inhibitor PD98059 did not affect the NO induction. Immunostaining of p65 and reporter gene assay showed that magnolol inhibited NF-${\kappa}/Rel$ nuclear translocation and transcriptional activation, respectively. Collectively, this series of experiments indicates that magnolol inhibits iNOS gene expression by blocking NF-k/Rel and p38 kinase signaling. Due to the critical role that NO release plays in mediating inflammatory responses, the inhibitory effects of magnolol or iNOS suggest that magnolol may represent a useful anti-inflammatory agent.

An Enhanced Biometric-Based Three Factors User Authentication Scheme for Multi-server Environments

Youping Lin,Kaihui Wang,Baocan Zhang,Yuzhen Liu,Xiong Li 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.1

Authentication is an important and basic security service for many network based applications, which allows the registered user access remote services after the validity of his/her identity is verified by the remote server. Password, smart card and biometric are three frequently used factors in authentication, and some remote user authentication schemes for different environments had been presented based on these factors by researchers. Recently, Baruah et al. pointed out the weaknesses of Mishra et al.’s three factors user authentication scheme for multi-server environments, and they proposed an enhanced scheme. They claimed that their scheme has many security features and can resist some common attacks. However, based on our analysis, Baruah et al.’s scheme cannot resist stolen smart card attack, cannot protect user’s anonymity, and it is also vulnerable to Denial of Service attack. In this paper, an enhanced three factors user authentication scheme for multi-server environments based on fuzzy extractor technology is proposed, and the analysis show that the proposed scheme is more security and efficient than other related schemes.

Experimental investigation of the preferred Strouhal number used in self-resonating pulsed waterjet

Deng Li,Youping Chen,Yong Kang,Zu’an Wang,Xiaoliang Wang,Qi Fan,Miao Yuan 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.9

Self-resonating pulsed waterjet (SRPW) is superior to plain waterjet in many ways and is being employed in numerous applications. To further improve the performance of SRPW, the optimal value of the preferred Strouhal number (S d ), which is used to determine the chamber length of a self-resonating nozzle, was experimentally studied at inlet pressures of 10 MPa and 20 MPa. The axial pressure oscillation peak and amplitude were used to evaluate the performance of SRPW, in order to find the optimum S d value. Results show that S dvalue determines the self-resonance behavior of an organ-pipe nozzle and greatly affects the intensity of the axial pressure oscillation. Under the experimental conditions, the optimum S d values are 0.315 and 0.278 respectively, corresponding to inlet pressures of 10 MPa and 20 MPa. Compared with the default value of 0.3 obtained from air jet experiment, the optimum S d value at inlet pressure of 10 MPa is a little larger and oppositely a bit smaller at inlet pressure of 20 MPa. Thus, if the inlet pressure is not considered, S d value of 0.3 is reasonable for determining the chamber length of a self-resonating nozzle for generating effective SRPW.

Spatiotemporal Variations and Possible Sources of Ambient PM10 from 2003 to 2012 in Luzhou, China

Dong Ren,Youping Li,Hong Zhou,Xiaoxia Yang,Xiaoman Li,Xuejun Pan,Bin Huang 대한환경공학회 2014 Environmental Engineering Research Vol.19 No.4

Descriptive statistics methods were used to study the spatiotemporal variations and sources of ambient particulate matter (PM10) in Luzhou, China. The analyzed datasets were collected from four national air quality monitoring stations: Jiushi (S1), Xiaoshi (S2), Zhongshan (S3), Lantian (S4) over the period of 2003-2012. This city was subjected serious PM10 pollution, and the long-term annual average PM10 concentrations varied from 76 to 136 μg/m3. The maximum concentration was more than 3-fold of the annual average (40 μg/m3) issued by EPA-China for the ambient air quality. General temporal pattern was characterized by high concentrations in winter and low concentrations in summer, and general spatial gradient was in the reduction order of S2 > S4 > S3 > S1, which were both due to different particulate contributors and special meteorological conditions. The source apportionment indicated that vehicular emissions, road dusts, coal burning and chemical dusts were the major contributors of the identified PM10 pollution, and the vehicular emissions and the road wear re-suspended particles dominated the heavy PM10 pollution in recent years. Two other potential sources, agricultural and celebration activities could decrease the air quality in a short term. Finally, some corresponding suggestions and measures were provided to improve the air quality.

Magnolol Inhibits iNOS, p38 Kinase, and NF-κB/Rel in Murine Macrophages

Mei Hong Li,In Youp Chang,Ho Jin You,Dae Sik Jang,Jin Sook Kim,Young Jin Jeon 한국독성학회 2006 Toxicological Research Vol.22 No.3

We demonstrate that magnolol, a hydroxylated biphenyl compound isolated from Magnolia officinalis, inhibits LPS-induced expression of iNOS gene in RAW 264.7 cells (murine macrophage cell line). Treatment of RAW 264.7 cells with magnolol inhibited LPS-stimulated nitric oxide production in a dose-related manner. RT-PCR analysis showed that the decrease of NO was due to the inhibition of iNOS gene expression. Western immunoblot analysis of phosphorylate p38 kinase showed magnolol significantly inhibited the phosphorylation of p38 kinase which is important in the regulation of iNOS gene expression. The specific p38 inhibitor SB203580 abrogated the LPSinduced NO generation and iNOS expression, whereas the selective MEK-1 inhibitor PD98059 did not affect the NO induction. Immunostaining of p65 and reporter gene assay showed that magnolol inhibited NF-κ/Rel nuclear translocation and transcriptional activation, respectively. Collectively, this series of experiments indicates that magnolol inhibits iNOS gene expression by blocking NF-κ/Rel and p38 kinase signaling. Due to the critical role that NO release plays in mediating inflammatory responses, the inhibitory effects of magnolol on iNOS suggest that magnolol may represent a useful anti-inflammatory agent.

Temporal distribution, influencing factors and pollution sources of urban ambient air quality in Nanchong, China

Hong Zhou,Youping Li,Huifang Liu,Zhongyu Fan,Jie Xia,Shanli Chen,Yuxiang Zheng,Xiaocui Chen 대한환경공학회 2015 Environmental Engineering Research Vol.20 No.3

The PM10, SO₂ and NO₂ mass concentrations were obtained over five years from monitoring stations across Nanchong, a southwest city in China. Changes in urban air quality over time, as well as the factors influencing that change, were evaluated based on air pollutant concentrations, the Air Pollution Index (API), and the Comprehensive Pollution Index (P). The results showed that the total annual mean PM10, SO₂ and NO₂ concentrations over the five years studied were 61.1±1.1, 45.0±3.9 and 34.9±4.9 μg·m-3, respectively. The annual mean concentrations displayed a generally decreasing trend; lower than the annual mean second-level air quality limit. Meanwhile, the annual mean API values were in a small range of 52-53, the air quality levels were gradeⅡ, and P values were 1.06-1.21 less than the slight level (P ≤ 1.31). Total monthly mean PM10, SO₂, NO₂ concentrations, and API and P values were consistently higher in winter and spring than during autumn and summer. The results of a correlation analysis showed that temperature and pressure were the major meteorological factors influencing pollution levels. Pollution sources included industrial coal and straw burning, automobiles exhaust and road dust, fireworks, and dust storms.

STRUCTURAL CHARACTERIZATION OF AL FIMS DEPOSITED ON TiN/Si SYBSTRATE BY METAL ORGANIC CHEMICAL VAPOR DEPOSITION

Kim, Kim, Byoung-Youp,Li, Li, Xiaodong,Rhee, Rhee, Shi-Woo 한국재료학회 1995 Fabrication and Characterization of Advanced Mater Vol.2 No.4

Al films deposited on sputtered-TiN substrate by metal organic chemical vapor deposition (MOCVD) from DMEAA were characterized using X-ray diffraction (XRD), Auger electron spectroscopy(AES), transmission electron microscopy(TEM), and atomic force microscopy(AFM). Deposition rate showed increase-maximum-decrease pattern in the temperature ragne of 100~25$0^{\circ}C$ with maximum deposition rate around 15$0^{\circ}C$. The film deposited at low temperatures showed equiaxed grains, and at high temperatures elongated block-like grains along with alumnum oxide particle inclusions were observed. There exist many dislocations at the Al/TiN interface. Aluminum oxide phase was formed at the Al/TiN interace during the early stage of Al deposition.

Radicicol Inhibits iNOS Expression in Cytokine-Stimulated Pancreatic Beta Cells

Youn, Cha Kyung,Park, Seon Joo,Li, Mei Hong,Lee, Min Young,Lee, Kun Yeong,Cha, Man Jin,Kim, Ok Hyeun,You, Ho Jin,Chang, In Youp,Yoon, Sang Pil,Jeon, Young Jin The Korean Society of Pharmacology 2013 The Korean Journal of Physiology & Pharmacology Vol.17 No.4

Here, we show that radicicol, a fungal antibiotic, resulted in marked inhibition of inducible nitric oxide synthase (iNOS) transcription by the pancreatic beta cell line MIN6N8a in response to cytokine mixture (CM: TNF-${\alpha}$, IFN-${\gamma}$, and IL-$1{\beta}$). Treatment of MIN6N8a cells with radicicol inhibited CM-stimulated activation of NF-${\kappa}B$/Rel, which plays a critical role in iNOS transcription, in a dose-related manner. Nitrite production in the presence of PD98059, a specific inhibitor of the extracellular signal-regulated protein kinase-1 and 2 (ERK1/2) pathway, was dramatically diminished, suggesting that the ERK1/2 pathway is involved in CM-induced iNOS expression. In contrast, SB203580, a specific inhibitor of p38, had no effect on nitrite generation. Collectively, this series of experiments indicates that radicicol inhibits iNOS gene expression by blocking ERK1/2 signaling. Due to the critical role that NO release plays in mediating destruction of pancreatic beta cells, the inhibitory effects of radicicol on iNOS expression suggest that radicicol may represent a useful anti-diabetic activity.

브랜드 글로벌성 vs. 원산지 이미지 -글로벌 브랜드는 원산지 효과에서 자유로운가?

한충민 ( C. Min Han ),이슬기 ( Seul Li Lee ),이상엽 ( Sang Youp Rhee ) 한국국제경영학회 2011 國際經營硏究 Vol.22 No.4

본 연구는 소비자가 지각하는 브랜드 글로벌성과 원산지 이미지가 외국 브랜드 평가에 미치는 영향을 실증적으로 분석한 연구이다. 특히 브랜드 글로벌성이 원산지 이미지의 효과를 조절하는지 즉 글로벌성이 높은 브랜드는 낮은 브랜드에 비해 원산지 효과가 낮아지는지를 검증하고자 하였다. 이를 위해 20-30대 성인을 중심으로 일본 자동차 4개 브랜드를 대상으로 설문조사를 실시하였다. 실증 분석 결과, 우선 브랜드 글로벌성이 소비자의 브랜드 평가에 미치는 영향은 유의한 반면에, 원산지 이미지는 유의하지 않았다. 이와 함께 브랜드 글로벌성이 원산지 이미지의 효과를 조절하는 경향이 있음이 발견되었다. 더 흥미로운 점은 원산지 효과가 글로벌성이 높은 브랜드에서는 나타난 반면에 글로벌성이 낮은 브랜드에서는 나타나지 않았다. 이 결과는 브랜드 글로벌성이 커지면 원산지효과가 줄어들 것이라는 일반적인 기대와 상반되는 것이다. 마지막으로 학술적인 측면뿐만 아니라 마케팅 관점에서 시사점이 논의된다. This study is intended to empirically investigate the effects of consumer perceived brand globalness and country-of-origin image on consumer evaluations of foreign brands. We hypothesize that perceived brand globalness moderates country-of-origin effects in brand effects. Surveys were carried out with adult consumers aged 20`s and 30`s on their evaluations of four Japanese automobile brands. Our findings support the effects of perceived brand globalness, but not country-of- origin effects in consumer evaluation of foreign brands. More importantly, we found that perceived brand globalness moderates the country-of-origin effects. This finding contrasts with our expectation from previous research. Finally, academic and practical implications are discussed.