Late Ordovician provenance and depositional setting in the southwestern Ordos Block, China: constraints from zircon U-Pb geochronology

Fu Yang,Gang Chen,Yu Kang,Dongmin Ma,Qilin Chen,Tian Tao,Fu Deliang 한국지질과학협의회 2020 Geosciences Journal Vol.24 No.2

The U-Pb ages of single zircon grains contained in the sandstone samples were analyzed by the LA-ICP-MS method, the sediment provenances and geological significance were discussed. The LA-ICP-MS zircon U-Pb dating from the sandstones, tuffaceous sandstones and volcanic tuffs of the Pingliang and Zhaolaoyu Formations along the southwestern Ordos Block are used to limit the maximum depositional age and material sources. The results show that: (1) The youngest ages of zircon dating in the three samples are 445 Ma, 444 Ma and 443 Ma, respectively, suggesting that the studied Formations were deposited in the Late Ordovician. (2) The detrital zircon U-Pb age analysis of the sandstones sample from the Pinliang Formation clustered in the 445–477 Ma, 588–1548 Ma and 1612–2496 Ma with the corresponding youngest peak age of 454.5 ± 3.3 Ma. (3) The distribution of zircon U-Pb age in sandstone samples showing that the sedimentary rocks detritus was mainly sourced from the North Qinling-Qilian terranes and the NCC, and has double provenance supply in the north and south. The material source of the tuffaceous sandstones and volcanic tuffs mainly comes from the volcanic and magmatic activity related to the North Qilian-North Qinling Island Arcs.

The Effects of Insulin-like Growth Factor-I(IGF-I) on Osteoblastic Cells : Role of Voltage-Activated Calcium Channels

Ma, Gang,Marzec, Nancy,Dziak, Rosemary Korean Academy of Oral Biology and the UCLA Dental 2001 International Journal of Oral Biology Vol.26 No.1

The goal of this present study was to investigate the effects of insulin-like growth factor (IGF-I) on osteoblastic cell proliferation, and the possible involvement of the alpha 1 subunit of L-type voltage activated calcium channels (L-VACC) in the regulation of these effects. In rat calvarial osteoblastic cells, incubation with 100 nM IGF-I for 24 hours significantly increased cell proliferation. The IGF-I-induced increase in cell proliferation was inhibited by verapamil (10-100 μM), a blocker of L-VACCs. In order to further investigate which isoform(s) of L-VACCs is involved in the effect of IGF-I, antisense oligodeoxynucleotides (ODNs) specific for alpha 1S (skeletal), alpha 1C (cardiac) or alpha 1D (neuroendocrine) of L-VACC were used to inhibit the expression of the different isoforms. The results showed that the proliferative response to IGF-I was significantly inhibited by the antisense ODN directed to the alpha 1C of L-VACC (decrease by 28%, P<0.05, ANOVA), but not by sense to alpha 1C or antisense/sense ODNs to alpha 1S and alpha 1D. The data suggest that the cardiac isoform of the L-VACC is at least partially responsible for IGF-I-induced increases in rat osteoblastic cell proliferation.

Mechanical response of rockfills in a simulated true triaxial test: A combined FDEM study

Ma, Gang,Chang, Xiao-Lin,Zhou, Wei,Ng, Tang-Tat Techno-Press 2014 Geomechanics & engineering Vol.7 No.3

The study of the mechanical behavior of rockfill materials under three-dimensional loading conditions is a current research focus area. This paper presents a microscale numerical study of rockfill deformation and strength characteristics using the Combined Finite-Discrete Element Method (FDEM). Two features unique to this study are the consideration of irregular particle shapes and particle crushability. A polydisperse assembly of irregular polyhedra was prepared to reproduce the mechanical behavior of rockfill materials subjected to axial compression at a constant mean stress for a range of intermediate principal stress ratios in the interval [0, 1]. The simulation results, including the stress-strain characteristics, relationship between principal strains, and principal deviator strains are discussed. The stress-dilatancy behavior is described using a linear dilatancy equation with its material constants varying with the intermediate principal stress ratio. The failure surface in the principal stress space and its traces in the deviatoric and meridian plane are also presented. The modified Lade-Duncan criterion most closely describes the stress points at failure.

초과통근분석을 위한 공간적 경계 설정에 관한 연구

마강래(Ma, Gang-Rae),김동호(Kim, Dong-Ho),추상호(Chu, Sang-Ho) 대한교통학회 2007 대한교통학회 학술대회지 Vol.55 No.-

초과통근 (excess commuting)은 선형계획기법의 교통문제 (transportation problem)를 통해, 도시 내의 총통근비용을 최소화하는 이상적인 통행패턴이 현실의 통행패턴과 어느 정도 괴리를 나타내고 있는 지 보여주는 지표이다. 과거 20년이 넘게 진행되어 온 초과통근에 대한 기존 연구들은 직장지와 주거지의 공간적 불일치라는 개념 속에서 지속가능한 교통정책과 토지이용정책의 중요성을 보여주었다. 그러나 최근의 연구문헌에 의하면 교통분석 존 (traffic analysis zone)에 기반을 둔 초과통근의 추정 기법은 공간적 분석단위의 변경에 민감하게 반응할 수 있음이 제시되었다. 특정 도시를 대상으로 한 연구에서도 공간적 분석단위의 변경으로 인해 상이한 초과통근량을 추정할 수 있음은 추정 기법의 신뢰성에 근본적인 의문을 갖게 하는 원인으로 작용하였다. 공간적 분석 단위에 대한 고려는, 존의 집계수준 (level of zonal aggregation), 존의 배열 (zonal configuration), 도시의 경계설정 (area boundary)과 관련되어 있다. 기존의 연구에서는 존의 집계수준과 배열이 초과통근 값을 어떻게 변화시키는 지에 대한 실증적 연구가 진행되었지만, 상이한 도시경계의 설정에 관련한 실증분석이나 정책적 함의에 대한 논의는 이루어지지 않았다.

교통패널자료 분석의 유용성 및 활용방안

마강래(Ma, Gang-Rae),김찬성(Kim, Chan-Seong) 대한교통학회 2007 대한교통학회 학술대회지 Vol.55 No.-

동적패널모형(dynamic panel model)은 기존의 정적모형(static model)의 대안적 또는 보완적 모델로 그 중요성이 부각되고 있다. 동적패널모형은 현재 나타나고 있는 개개인들의 행태가 현재뿐만 아니라 과거에도 종속되어 영향받고 있으므로 정적모형에서 강조하는 균형(equilibrium) 상태가 존재하기 힘듦을 강조하고 있다. 예를 들어 외부 환경의 변화에 대한 저항(resistance to change)은 ‘습관’(habit)이나 ‘상태지속성’(state-dependence) 등과 같은 인자들을 통해서 나타나며, 이는 반응시차(lags)를 발생시키는 역할을 담당한다. 동적모형의 중요성은 지금까지 축적되어 왔던 과거의 경험이나 지식 등이 현재의 통행행태에 영향을 주는 중요한 요인임을 인식함으로써 모형의 예측력을 증가시키는 데 있다.

양양 류씨와 남조정치 -남도사족개안연구지일-

마지강 ( Ma Ji Gang ) 대구사학회 2004 대구사학 Vol.74 No.-

以襄陽爲中心居住區的荊襄晩渡士族, 其核心家族有薛, 韋, 杜, 柳等北方舊姓, 他們素以武勇善戰著名於東晋南朝. 雖然他們因南來較晩而被目爲所謂荒창, 但縱觀南朝歷史, 擧凡抗胡, 御邊, 伐만, 內爭等重大政治事件, 无不有他們活動的身影, 在某??程度上甚至可以說, 南朝政治的治亂與否, 社會的穩定與否, 與之休戚相關. 而在這些南渡軍功家族中, 河東柳氏??其値得注意.

Assessment of the crest cracks of the Pubugou rockfill dam based on parameters back analysis

Zhou, Wei,Li, Shao-Lin,Ma, Gang,Chang, Xiao-Lin,Cheng, Yong-Gang,Ma, Xing Techno-Press 2016 Geomechanics & engineering Vol.11 No.4

The crest of the Pubugou central core rockfill dam (CCRD) cracked in the first and second impounding periods. To evaluate the safety of the Pubugou CCRD, an inversion analysis of the constitutive model parameters for rockfill materials is performed based on the in situ deformation monitoring data. The aim of this work is to truly reflect the deformation state of the Pubugou CCRD and determine the causes of the dam crest cracks. A novel real-coded genetic algorithm based upon the differences in gene fragments (DGFX) is proposed. It is used in combination with the radial based function neural network (RBFNN) to perform the parameters back analysis. The simulated settlements show good agreements with the monitoring data, illustrating that the back analysis is reasonable and accurate. Furthermore, the deformation gradient of the dam crest has been analysed. The dam crest has a great possibility of cracking due to the uncoordinated deformation, which agrees well with the field investigation. The deformation gradient decreases to the value lower than the critical one and reaches a stable state after the second full reservoir.

Serum lipocalin-2 is a potential biomarker for the clinical diagnosis of nonalcoholic steatohepatitis

( Gang Xu ),( Yu-min Wang ),( Miao-miao Ying ),( Sui-dan Chen ),( Zong-rui Li ),( Hong-lei Ma ),( Ming-hua Zheng ),( Jian Wu ),( Chunming Ding ) 대한간학회 2021 Clinical and Molecular Hepatology(대한간학회지) Vol.27 No.2

Background/Aims: Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD) characterized by hepatic steatosis, inflammation, hepatocellular injury, and fibrosis. We aimed to investigate the usefulness of a key biomarker, lipocalin-2 (LCN2), for the detection of NASH progression. Methods: A mouse NASH model was established using a high-fat diet and a high-sugar drinking water. Gene expression profile of the NASH model was analyzed using RNA sequencing. Moreover, 360 NAFLD patients (steatosis, 83; NASH, 277), 40 healthy individuals, and 87 patients with alcoholic fatty liver disease were recruited. Results: Inflammatory infiltration, focal necrosis in the leaflets, steatosis, and fibrosis were documented in the mouse liver. In total, 504 genes were differentially expressed in the livers of NASH mice, and showed significant functional enrichment in the inflammation-related category. Upregulated liver LCN2 was found to be significantly interactive with various interleukins and toll-like receptors. Serum LCN2 levels were significantly increased in NAFLD patients. Serum LCN2 levels were correlated with steatosis, intralobular inflammation, semiquantitative fibrosis score, and nonalcoholic fatty liver disease activity score. The area under the curve of serum LCN2 was 0.987 with a specificity of 100% and a sensitivity of 93.5% for NASH diagnosis, and 0.977 with almost the same specificity and sensitivity for steatosis. Conclusions: LCN2 might be involved in the transition from NAFL to NASH by mediating inflammation. Serum LCN2 levels might be a novel biomarker for the diagnosis of NASH. (Clin Mol Hepatol 2021;27:329-345)

Inhibition of RIPK1-dependent regulated acinar cell necrosis provides protection against acute pancreatitis via the RIPK1/NF- κB/AQP8 pathway

Gang Wang,Peng-yu Duan,Yuan Ma,Xi-na Li,Feng-zhi Qu,Liang Ji,Xiao-yu Guo,Wang-jun Zhang,Fan Xiao,Le Li,Ji-sheng Hu,Bei Sun 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Currently, preliminary results have confirmed the existence of receptor-interacting protein kinase 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL)-dependent necroptosis of pancreatic acinar cells during early acute pancreatitis (AP), which might be a potential target for the effective regulation of necroinflammatory injury. However, the exact effect of receptor-interacting protein kinase 1 (RIPK1)-dependent regulated acinar cell necrosis on AP is still uncertain. In our study, we first explored the changes in the degree of local and systemic inflammation in AP rats when the activation of acinar cell RIPK1 was inhibited. The RIPK1 inhibitor Nec-1 was used to treat rats, and the levels of related inflammatory markers, necrosis indicators and apoptotic indicators were measured. Changes in pancreatic nuclear factor κB (NF-κB) and aquaporin 8 (AQP8) expression were noted. Next, the expression of AQP8 in AR42J cells was inhibited, and the degree of cell necrosis and inflammatory damage was found to be significantly reduced. Most importantly, we demonstrated that the RIPK1/NF-ĸB/AQP8 axis might be a potential regulatory pathway mediating RIPK1-dependent regulated acinar cell necrosis in early AP. Finally, we used the NF-κB inhibitor PDTC and Nec-1 to treat rats in different groups and measured the degree of pathological pancreatic injury, the activation of RIPK1, and the expression of NF-κB and AQP8. In summary, we hypothesized that there might be a RIPK1/NF-ĸB/AQP8 pathway controlling RIPK1-dependent regulated necrosis of acinar cells in AP, which might be a promising therapeutic target against AP-related injury.

China´s Coastal Development Strategy and Oacific Rim Economic Integration

MA,Jun,ZOU, Gang,WANG, Zhigang THE INSTITUTE OF EAST AND WEST STUDIES YONSEI UNIV 1990 Global economic review Vol.19 No.2