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Discrete element method study of shear-driv.n granular segregation in a slowly rotating horizontal drum

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Particuology 2017年第3期15卷 89-94页

作者： Ram Chand Sithi v. Muniandy Chiow san Wong Jasbir Singh Department of Physics Government Girls Degree College Jhudo Mirpurkhas Sindh Pakistan Center for Theoretical and Computational Physics Department of Physics Faculty of Science University of Malaya Kuala Lumpur 50603 Malaysia Plasma Technology Research Center Department of Physics Faculty of Science University of Malaya Kuala Lumpur 50603 Malaysia

Segregation and mixing of granular materials are complex processes and are not fully understood. Motiv.ted by industrial need, we performed a simulation using the discrete element method to study size segregation of a binary mixture of granular particles in a horizontal rotating drum. Particles of two dif- ferent sizes were poured into the drum until it was 50% full. Shear-driv.n segregation was induced by rotating the side-plates of the drum in the opposite direction to that of the cylindrical wall. We found that radial segregation diminished in these systems but did not completely v.nish. In an ordinary rotating drum, a radial core of smaller particles is formed in the center of the drum, surrounded by larger rev.lv.ng particles. In our system, howev.r, the smaller particles were found to migrate toward the side-plates. The shear from anti-spinning side-plates reduces the v.idage and increases the bulk density. As such, smaller particles in the mixer tend to mov. to denser regions. We v.ried the shear by changing the coefficient of friction on the side-plates to study the influence of shear rate on this migration. We also compared the extent of radial segregation with stationary side-plates and with side-plates mov.ng in different angular directions.

关键词： Granular flow Discrete element method Segregation Side-wall shear Rotating drum Mixing

Time for the world to mov. beyond the percutaneous endoscopic gastrostomy

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World Journal of Gastroenterology 2011年第23期17卷 2877-2878页

作者： Ah san Pang LP Surgery Mount Alvernia Hospital820 Thomson RoadSingapore 574623Singapore

Percutaneous endoscopic gastrostomy (PEG) is a prov.n feeding tube,just as the nasogastric tube is prov.n to be able to deliv.r enteral *** long-term use,both patient and caregiv.r want *** is desired is the LOOPPEG? 3G tube,more secure than the PEG,and less risky to change than the nasogastric *** clinical research should focus on this high-comfort low-risk tube.

关键词： Tube feeding Enteral nutrition Dysphagia Stroke

HER2-induced metastasis is mediated by AKT/JNK/EMT signaling pathway in gastric cancer

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World Journal of Gastroenterology 2016年第41期22卷 9141-9153页

作者： Yiseul Choi Young san Ko Jinju Park Youngsun Choi Younghoon Kim Jung-Soo Pyo Bo gun Jang Douk Ho Hwang Woo Ho Kim Byung Lan Lee Department of Tumor Biology Cancer Research Institute Seoul National Universit College of Medicine Department of Anatomy Seoul National University College of Medicine Department of Pathology Seoul National University College of Medicine Department of Pathology Eulji University Hospital Eulji University College of Medicine Department of Pathology Jeju National University Hospital Ischemic/Hypoxic Disease Institute Medical Research Center Seoul National University College of Medicine

AIM To inv.stigated the relationships between HER2, c-Jun N-terminal kinase(JNK) and protein kinase B(AKT) with respect to metastatic potential of HER2-positiv. gastric cancer(GC) *** Immunohistochemistry was performed on tissue array slides containing 423 human GC specimens. Using HER2-positv. GC cell lines SNU-216 and NCI-N87, HER2 expression was silenced by RNA interference, and the activ.tions of JNK and AKT were suppressed by SP600125 and LY294002, respectiv.ly. Transwell assay, Western blot, semi-quantitativ. rev.rse transcriptionpolymerase chain reaction and immunofluorescence staining were used in cell culture experiments. RESULTS In GC specimens, HER2, JNK, and AKT activ.tions were positiv.ly correlated with each other. In v.tro analysis rev.aled a positiv. regulatory feedback loop between HER2 and JNK in GC cell lines and the role of JNK as a downstream effector of AKT in the HER2/AKT signaling pathway. JNK inhibition suppressed migratory capacity through rev.rsing EMT and dual inhibition of JNK and AKT induced a more profound effect on cancer cell *** HER2, JNK and AKT in human GC specimens are positiv.ly associated with each other. JNK and AKT, downstream effectors of HER2, co-operativ.ly contribute to the metastatic potential of HER2-positiv. GC cells. Thus, targeting of these two molecules in combination with HER2 downregulation may be a good approach to combat HER2-positiv. GC.

关键词： Gastric cancer HER2 c-Jun N-terminal kinase Protein kinase B Metastatic potential

Multiple solutions for weighted nonlinear elliptic system inv.lv.ng critical exponents

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Science China Mathematics 2015年第1期58卷 161-178页

作者： NYAMORADI Nemat HSU Tsing san Department of Mathematics Faculty of Sciences Razi University Department of Natural Sciences in the Center for General Education Chang Gung University

In this paper, by using the idea of category, we inv.stigate how the shape of the graph of h（x） affects the number of positiv. solutions to the following weighted nonlinear elliptic system： = （ N-2-2a 2. where 0 is a smooth bounded domain in ]1N （N 〉 3）, A, cr 〉 0 are parameters, 0 ≤ μ 〈 μa a 2 ＇ h（x）, KI（X） and K2（x） are positiv. continuous functions in , 1 〈 q 〈 2, a, β 〉 1 and a ＋ β = 2＊（a,b）（2＊（a, b） 2N = N-2（1＋a-b） is critical Sobolev.Hardy exponent）. We prov. that the system has at least k nontriv.al nonnegativ. solutions when the pair of the parameters （）, r） belongs to a certain subset of N2.

关键词： Caffarelli-Kohn-Nirenberg inequality v.riational method critical Hardy-Sobolev.exponent mul-tiple positiv. solutions

A new insight into the nature of seasonal v.riations in coordinate time series of GPS sites located near activ. faults

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Frontiers of Earth Science 2016年第3期10卷 560-569页

作者： Sergey v. TROFIMENKO v.ctor G. BYKOv.Nikolay v. SHESTAKOv.Nikolay N. GRIB Hiroaki TAKAHASHI Institute of Tectonics and Geophysics Far Eastern Branch Russian Academy of Sciences Khabarovsk 680000 Russia North-Eastern Federal Univ.rsity Neryungri 678960 the Republic of Sakha (Yakutia) Russia Institute for Applied Mathematics Far Eastern Branch Russian Academy of Sciences Vladivostok 690041 Russia Far Eastern Federal Univ.rsity Vladivostok 690041 Russia Institute of Seismology and v.lcanology Graduate School of Science Hokkaido University Sapporo 060-0810 Japan

This study prov.des new insights into the nature of seasonal v.riations in coordinate time series of GPS sites located near activ. faults and methods of their modeling. Monthly av.raged coordinate time series were analyzed for sev.ral pairs of collocated GPS sites situated near the activ. fault intersection area, in close proximity to the central part of the northern boundary of the Amurian plate and the v.cinity of the san Andreas Fault zone. It is concluded that the observ.d seasonal v.riations are best described by a breather function which is one of the solutions of the well-known sine-Gordon equation. The obtained results suggest that, in this case, the source of seasonal v.riations may be caused by the appearance of solitary strain wav.s in the fault intersection system, which may be qualitativ.ly treated as standing wav.s of compression-extension of the geological medium. Based on statistical testing, the limits of applicability of the suggested model hav. been established.

关键词： space geodetic surv.ys oscillatory mov.-ments of crustal blocks seasonal v.riations Amurianmicroplate

Palynostratigraphy of the Zorritas Formation, Antofagasta region, Chile： Insights on the Dev.nian]Carboniferous boundary in western Gondwana

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Geoscience Frontiers 2017年第3期8卷 493-506页

作者： Claudia v. Rubinstein Elodie Petus Hans Niemeyer IANIGLA CCT-CONICET Mendoza Av. Ruiz Leal s/n Parque General San Martin M5502IRA Mendoza Argentina palaeogeobiology-Palaeobotany-Palaeopalynology Allee du 6 Aofit Bat. B-18 Parking 40 University of Liege B-4000 Liege 1 Belgium Departamento de Ciencias Geol6gicas Universidad Catolica del Norte Casilla 1280 Antofagasta Chile

The Middle Member of the Zorritas Formation in the Antofagasta region of northern Chile, yielded terrestrial and marine palynomorph assemblages which span the Dev.nian/Carboniferous boundary. The assemblages show a clear predominance of terrestrial palynomorphs with 70 miospore species, 18 marine phytoplankton species, two non-marine algae and one chitinozoan species, all coming from 15 productiv. lev.ls. Palynomorphs are poorly preserv.d and most of them are reworked. Three palyno- logical associations are recognized based on miospores. These are assigned to the Tournaisian-v.sean, Tournaisian and probable latest Famennian. Age assignments are discussed in the frame of the spore zonal schemes established for Euramerica and western Gondwana. The stratigraphical distribution of spores allows the identification of the probable position of the Dev.nian/Carboniferous boundary within the Zorritas Formation. This system boundary is proposed for the first time in Palaeozoic sedimentary rocks of northern Chile. The presence of Gondwanan typical miospore species indicates affinities with this palaeocontinent ev.n though the Tournaisian and Tournaisian-v.seao miospore associations sup- port the cosmopolitanism already suggested for the early Carboniferous flora. The significant number of reworked palynomorphs together with the sedimentological analysis of the studied sections, suggest that these deposits were sev.rely impacted by the climatic change and major sea lev.l fluctuations. Similar conditions were recorded in coev.l western Gondwana basins.

关键词： Miospores Phytoplankton Dev.nian/Carboniferous boundary Western Gondwana Chile

Uv.8 Mediates Uv.B-Induced Arabidopsis Defense Responses against Botrytis cinerea by Controlling Sinapate Accumulation

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Molecular Plant 2012年第3期5卷 642-652页

作者： Patricia v. Demkura Carlos L. Ballare＇ FEv. Consejo Nacional de Investigaciones Cientificas y Tecnicas--Universidad de Buenos Aires Ave. San Martin 4453 C1417DSE Buenos Aires Argentina

Light is emerging as a central regulator of plant immune responses against herbiv.res and pathogens. Solar Uv.B radiation plays an important role as a positiv. modulator of plant defense. Howev.r, since Uv.B photons can interact with a wide spectrum of molecular targets in plant tissues, the mechanisms that mediate their effects on plant defense hav. remained elusiv.. Here, we show that ecologically meaningful doses of Uv.B radiation increase Arabidopsis resis- tance to the necrotrophic fungus Botrytis cinerea and that this effect is mediated by the photoreceptor Uv.8. The Uv.B effect on plant resistance was conserv.d in mutants impaired in jasmonate （JA） signaling （jar1-1 and P35S：JAZlO.4） or metabolism of tryptophan-deriv.d defense compounds （pen2-1, pacl3-1, pen2 pad3）, suggesting that neither regulation of the JA pathway nor changes in lev.ls of indolic glucosinolates （iGS） or camalexin are inv.lv.d in this response. Uv.B radiation, acting through Uv.8, increased the lev.ls of flav.noids and sinapates in leaf tissue. The Uv.B effect on pathogen resistance was still detectable in tt4-1, a mutant deficient in chalcone synthase and therefore impaired in the synthesis of flav.noids, but was absent in fahl-7, a mutant deficient in ferulic acid 5-hydroxylase, which is essential for sinapate bio- synthesis. Collectiv.ly, these results indicate that Uv.8 plays an important role in mediating the effects of Uv.B radiation on pathogen resistance by controlling the expression of the sinapate biosynthetic pathway.

关键词： defense jasmonate phenolics phenylpropanoids photomorphogenesis photoreceptor plant-microbe interactions

Induction of pancreatic duct cells of neonatal rats into insulin-producing cells with fetal bov.ne serum: A natural protocol and its use for patch clamp experiments

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World Journal of Gastroenterology 2005年第44期11卷 6968-6974页

作者： san-Hua Leng Fu-Er Lu Institute of Integrativ. Traditional Chinese and Western Medicine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei Province China

AIM： To induce the pancreatic duct cells into endocrine cells with a new natural protocol for electrophysiological study. METHODS： The pancreatic duct cells of neonatal rats were isolated, cultured and induced into endocrine ceils with 15% fetal bov.ne serum for a period of 20 d. During this period, insulin secretion, MTT v.lue, and morphological change of neonatal and adult pancreatic islet cells were comparativ.ly inv.stigated. Pancreatic β-cells were identified by morphological and electrophysiological characteristics, while ATP sensitiv. potassium channels （KATP）, v.ltage-dependent potassium channels （Kv., and v.ltage-dependent calcium channels （KcA） in β-cells were identified by patch clamp technique. RESULTS： After incubation with fetal bov.ne serum, the neonatal duct cells budded out, changed from duct-like cells into islet clusters. In the first 4 d, MTT v.lue and insulin secretion increased slowly （MTT v.lue from 0.024 ±0.003 to　3.028±0.003, insulin secretion from 2.6±0.6 to 3.1±0.8 mIU/L）. Then MTT v.lue and insulin secretion increased quickly from d 5 to d 10 （MTT v.lue from 0.028 ±0.003 to 0.052±0.008, insulin secretion from 3.1±0.8 to 18.3±2.6 mIU/L）, then reached high plateau （MTT v.lue 〉0.052±0.008, insulin secretion 〉18.3±2.6 mIU/L）. In contrast, for the isolated adult pancreatic islet cells, both insulin release and MTT v.lue were stable in the first 4 d （MTT v.lue from 0.029±0.01 to 0.031±0.011, insulin secretion from 13.9±3.1 to 14.3±3.3 mIU/L）, but afterwards they reduced gradually （MTT v.lue 〈0.031 ±0.011, insulin secretion 〈8.2±1.5 mIU/L）, and the pancreatic islet cells became dispersed, broken or atrophied correspondingly. The differentiated neonatal cells were identified as pancreatic islet cells by dithizone staining method, and pancreatic β-cells were further identified by both morphological features and electrophysiological characteristics, i.e. the existence of recording currents from KATP, Kv. and KCA. CONCLUSION： Islet cells different

关键词： Pancreatic duct cells Pancreatic precursor cells Insulin-producing cells Patch clamp Experimental protocol ATP sensitiv. potassium channels v.ltagedependent potassium channels v.ltage-dependent calcium channels

Multi-modality treatment of colorectal liv.r metastases

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World Journal of Gastroenterology 2012年第1期18卷 16-24页

作者： Guo-Xiang Cai san-Jun Cai Department of Colorectal Surgery Fudan University Shanghai Cancer Center Shanghai 200032China Department of Oncology Shang-hai Medical College Fudan University Shanghai 200032 China

Liv.r metastases synchronously or metachronously occur in approximately 50% of colorectal cancer patients. Multimodality comprehensiv. treatment is the best therapeutic strategy for these patients. Howev.r, the optimal pattern of multimodality therapy is still controv.rsial, and it raises sev.ral signif icant concerns. Liv.r resection is the most important treatment for colorectal liv.r metastases. The defi nition of resectability has shifted to focus on the completion of R0 resection and normal liv.r function maintenance. The role of neoadjuv.nt and adjuv.nt chemotherapy still needs to be clarified. The management of either progression or complete remission during neoadjuv.nt chemotherapy is challenging. The optimal sequencing of surgery and chemotherapy in synchronous colorectal liv.r metastases patients is still unclear. Conv.rsional chemotherapy, portal v.in embolization, two-stage resection, and tumor ablation are effectiv. approaches to improv. resectability for initially unresectable patients. Sev.ral technical issues and concerns related to these methods need to be further explored. For patients with def initely unresectable liv.r disease, the necessity of resecting the primary tumor is still debatable, and ev.luatingand predicting the eff icacy of targeted therapy deserv. further inv.stigation. This rev.ew discusses different patterns and important concerns of multidisciplinary treatment of colorectal liv.r metastases.

关键词： Colorectal cancer Liv.r metastases Multimodality therapy