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Higher-order topological insulators in synthetic dimensions

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Light(Science & Applications) 2020年第1期9卷 831-839页

作者： Avik Dutt Momchil Minkov ian A.D.Williamson Shanhui Fan Ginzton Laboratory and Department of Electrical Engineering Stanford UniversityStanfordCA 94305USA

Conventional topological insulators support boundary states with dimension one lower than that of the bulk system that hosts them,and these states are topologically protected due to quantized bulk dipole ***,higherorder topological insulators have been proposed as a way of realizing topological states with dimensions two or more lower than that of the bulk due to the quantization of bulk quadrupole or octupole ***,all these proposals as well as experimental realizations have been restricted to real-space ***,we construct photonic higher-order topological insulators(PHOTIs)in synthetic *** show the emergence of a quadrupole PHOTI supporting topologically protected corner modes in an array of modulated photonic molecules with a synthetic frequency dimension,where each photonic molecule comprises two coupled *** changing the phase difference of the modulation between adjacent coupled photonic molecules,we predict a dynamical topological phase transition in the ***,we show that the concept of synthetic dimensions can be exploited to realize even higher-order multipole moments such as a fourth-order hexadecapole(16-pole)insulator supporting 0D corner modes in a 4D hypercubic synthetic lattice that cannot be realized in real-space lattices.

关键词： topological dimensions insulator

Sediment transport in ice-covered channels

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International Journal of Sediment Research 2015年第1期30卷 63-67页

作者： ian KNACK Hung-tao SHEN Department of Civil and Environmental Engineering Clarkson University

The existence of ice cover has important effects on sediment transport and channel morphology for rivers in areas with an annual occurrence of an ice *** interaction of sediment transport and surface ice is poorly *** this paper,data from existing flume experiments,each with a limited range of flow and sediment transport conditions,are *** analysis showed that the bed load transport in ice-covered channels can be described by conventional relationships for the equivalent free-surface flow if the flow strength is expressed in terms of the bed shear stress.A modified Rouse formulation considering the effect of the ice cover on velocity and turbulent diffusion is shown to be applicable for calculating the suspended sediment transport discharge.

关键词： Sediment transport Bed load Ice-covered channel Suspended load

Natural killer T cells and non-alcoholic fatty liver disease:Fat chews on the immune system

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World Journal of Gastroenterology 2008年第3期14卷 487-488页

作者： Michael Kremer ian N Hines Department of Surgery University of Heidelberg Heidelberg 69120 Germany Department of Medicine University of North Carolina at Chapel Hill CB 7525 United States

Natural killer T cells (NKT) are an important subset of T lymphocytes. They are unique in their ability to produce both T helper 1 and T helper 2 associated cytokines, thus being capable of steering the immune system into either inflammation or tolerance. Disruption of NKT cell numbers or function results in severe deficits in immune surveillance against pathogens and tumor cells. Growing experimental evidence suggests that hepatosteatosis may reduce resident hepatic as well as peripheral NKT cells. Those models of hepatosteatosis and the change in NKT cell numbers are associated with a disruption of cytokine homeostasis, resulting in a more pronounced release of proinflammatory cytokines which renders the steatotic liver highly susceptible to secondary insults. In this letter to the editor, we focus on recently published data in the World Journal of Gastroenterology by Xu and colleagues demonstrating reduced peripheral NKT cells in patients with non-alcoholic fatty liver disease, compare those findings with ours and others in different animal models of hepatosteatosis, and hypothesize about the potential underlying mechanism.

关键词： Obesity Hepatosteatosis Metabolic syndrome TNFalpha Interleukin 12

Roles of autophagy in lymphocytes： reflections and directions

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Cellular & Molecular Immunology 2010年第2期7卷 104-107页

作者： ian X McLeod Youwen He Department of Immunology Duke University Medical Center Durham NC USA

Recent studies have revealed that autophagy, a fundamental intracellular process, plays many different roles in lymphocyte development and function. Autophagy regulates naive T-lymphocyte homeostasis, specifically by regulating mitochondrial quality and turnover, and is necessary for the proliferation of mature T cells. Autophagy also acts as a cellular death pathway in lymphocytes, both upon prolonged cytokine withdrawal and during acute antigen-receptor stimulation if improperly regulated. Furthermore, during HIV infection, hyperinduction of autophagy leads to massive T-cell death in uninfected CD4＋ T cells, and is rescued by inhibiting autophagic initiation. Constitutively high levels of autophagy in thymic epithelial cells are necessary for optimal processing and presentation of endogenous antigens, and required for proper positive and negative selection of developing thymocytes. Autophagy also promotes the survival of B lymphocytes, as well as the development of early B-cell progenitors. In B cells, autophagy is an alternative death pathway, as antigen-receptor stimulation in the absence of costimulation induces a potent autophagic death. Thus, autophagy plays a complex role in lymphocytes and is regulated during their lifespan to ensure a healthy immune system.

关键词： apoptosis autophagy homeostasis lymphocytes

The commutant and similarity invariant of analytic Toeplitz operators on Bergman space

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Science China Mathematics 2007年第5期50卷 651-664页

作者： Chun-ian JianG Yu-cheng Li Department of Mathematics Hebei Normal UniversityShijiazhuang 050016China

The famous von Neumann-Wold Theorem tells us that each analytic Toeplitz operator with n + 1-Blaschke factors is unitary to n + 1 copies of the unilateral shift on the Hardy space. It is obvious that the von Neumann-Wold Theorem does not hold in the Bergman space. In this paper, using the basis constructed by Michael and Zhu on the Bergman space we prove that each analytic Toeplitz operator M B(z) is similar to n + 1 copies of the Bergman shift if and only if B(z) is an n + 1-Blaschke product. From the above theorem, we characterize the similarity invariant of some analytic Toeplitz operators by using K 0-group term.

关键词： Bergman space analytic Toeplitz operators invariant subspace commutant similarity invariant K 0-group 32A36 46J40 47A15

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HER2 inhibition in gastro-oesophageal cancer:A review drawing on lessons learned from breast cancer

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World Journal of Gastrointestinal Oncology 2018年第7期10卷 159-171页

作者： Hazel Lote Nicola Valeri ian Chau Centre for Molecular Pathology Institute of Cancer Research Department of Medicine Royal Marsden Hospital

Human epidermal growth factor receptor 2(HER2)-inhibition is an important therapeutic strategy in HER2-amplified gastro-oesophageal cancer(GOC).A significant proportion of GOC patients display HER2 amplification,yet HER2 inhibition in these patients has not displayed the success seen in HER2 amplified breast *** of the current evidence surrounding HER2 has been obtained from studies in breast cancer,and we are only recently beginning to improve our understanding of HER2-amplified *** there are numerous licensed HER2 inhibitors in breast cancer,trastuzumab remains the only licensed HER2 inhibitor for HER2-amplified *** trials investigating lapatinib,trastuzumab emtansine,pertuzumab and MM-111 in GOC have demonstrated disappointing results and have not yet changed the treatment *** deruxtecan may hold promise and is currently being investigated in phase Ⅱ ***2 amplified GOC differs from breast cancer due to inherent differences in the HER2 amino-truncation and mutation rate,loss of HER2 expression,alterations in HER2 signalling pathways and differences in insulin-like growth factor-1 receptor and MET *** alterations involving different micro RNA profiles in GOC as compared to breast cancer and intrinsic differences in the immune environment are likely to play a *** key to effective treatment of HER2 amplified GOC lies in understanding these mechanisms and tailoring HER2 inhibition for GOC patients in order to improve clinical outcomes.

关键词： Human epidermal growth factor receptor 2 Gastro-oesophageal cancer Trastuzumab Resistance Biomarkers Breast cancer

Opioid growth factor and the treatment of human pancreatic cancer:A review

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World Journal of Gastroenterology 2014年第9期20卷 2218-2223页

作者： ian S Zagon Patricia J McLaughlin Department of Neural and Behavioral Sciences Pennsylvania State University College of Medicine Hershey PA 17033 United States

Opioid growth factor (OGF), chemically termed [Met5]-enkephalin, and its receptor, OGF receptor (OGFr), form a biological axis that tonically regulates cell proliferation by delaying the G1/S interface of the cell cycle under homeostatic conditions or in neoplasia. Modulation of the OGF-OGFr pathway mediates the course of pancreatic cancer, with exogenous OGF or upregulation of OGFr repressing growth of human pancreatic cancer cells in culture and in nude mice. OGF therapy alone or in combination with standard chemotherapies such as gemcitabine and 5-fluorouracil results in enhanced inhibition of DNA synthesis and tumor growth. Molecular manipulation of OGFr confirms that the receptor is specific for OGF’s inhibitory action. Preclinical studies have warranted Phase I and Phase II clinical trials using OGF infusions as a treatment for patients with advanced, unresectable pancreatic cancers. OGF, an endogenous neuropeptide, is a safe, non-toxic, and effective biotherapy that utilizes the OGF-OGFr axis to mediate pancreatic tumor progression.

关键词： Enkephalins DNA synthesis Pancreatic adenocarcinoma Opioids Nude mice Receptor transfection

Hydrocele of the canal of Nuck—an old problem revisited

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Frontiers of Medicine 2013年第4期7卷 517-519页

作者： John Bunni Mark Gillam ian Michael Pope Department of General Surgery Bristol Royal InfirmaryBristol BS28HWUK

Herein the authors describe the case of a young woman presenting with a tender lump in her *** the differential was of either a reactive lymph node or a femoral *** scan was urgently arranged and showed a cystic *** exploration was carried out and revealed this to be a hydrocele of the canal of *** was excised and the patient’s symptoms resolved and she was discharged home the following *** explore the embryology,pathophysiology and management of this rare entity.

关键词： canal of Nuck hernia embryology

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On the Energy Self-Sustainability of IoT via Distributed Compressed Sensing

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China Communications 2020年第12期17卷 37-51页

作者： Wei Chen Nikos Deligiannis Yiannis Andreopoulos ian JWassell State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China Electronics and Informatics department Vrije Universiteit BrusselBrussel Pleinlaan 21050Belgium Department of Electronic and Electrical Engineering University College LondonLondon WC1E 6BTU.K. Computer Laboratory University of CambridgeCambridge CB30FDU.K imec Kapeldreef 75B-3001 LeuvenBelgium

This paper advocates the use of the distributed compressed sensing(DCS)paradigm to deploy energy harvesting(EH)Internet of Thing(IoT)devices for energy *** consider networks with signal/energy models that capture the fact that both the collected signals and the harvested energy of different devices can exhibit *** provide theoretical analysis on the performance of both the classical compressive sensing(CS)approach and the proposed distributed CS(DCS)-based approach to data acquisition for EH ***,we perform an in-depth comparison of the proposed DCSbased approach against the distributed source coding(DSC)*** performance characterizations and comparisons embody the effect of various system phenomena and parameters including signal correlation,EH correlation,network size,and energy availability *** results unveil that,the proposed approach offers significant increase in data gathering capability with respect to the CS-based approach,and offers a substantial reduction of the mean-squared error distortion with respect to the DSC system.

关键词： distributed compressed sensing energy harvesting internet of things energy self-sustainability

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