抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

We investigate electronic transport in lithographically patterned graphene ribbon structures where the lateral confinement of charge carriers creates an energy gap near the charge neutrality point. Individual graphene layers are contacted with metal electrodes and patterned into ribbons of varying widths and different crystallographic orientations. The temperature dependent conductance measurements show larger energy gaps opening for narrower ribbons. The sizes of these energy gaps are investigated by measuring the conductance in the nonlinear response regime at low temperatures. We find that the energy gap scales inversely with the ribbon width, thus demonstrating the ability to engineer the band gap of graphene nanostructures by lithographic processes.

Energy band-gap engineering of graphene nanoribbons.

In the coming decade, the ability to sense and detect the state of biological systems and living organisms optically, electrically and magnetically will be radically transformed by developments in materials physics and chemistry. The emerging ability to control the patterns of matter on the nanometer length scale can be expected to lead to entirely new types of biological sensors. These new systems will be capable of sensing at the single-molecule level in living cells, and capable of parallel integration for detection of multiple signals, enabling a diversity of simultaneous experiments, as well as better crosschecks and controls.

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The use of nanocrystals in biological detection

A revolution in electronics is in view, with the contemporary evolution of the two novel disciplines of spintronics and molecular electronics. A fundamental link between these two fields can be established using molecular magnetic materials and, in particular, single-molecule magnets. Here, we review the first progress in the resulting field, molecular spintronics, which will enable the manipulation of spin and charges in electronic devices containing one or more molecules. We discuss the advantages over more conventional materials, and the potential applications in information storage and processing. We also outline current challenges in the field, and propose convenient schemes to overcome them.

Molecular spintronics using single-molecule magnets

▪ Abstract Soft lithography, a set of techniques for microfabrication, is based on printing and molding using elastomeric stamps with the patterns of interest in bas-relief. As a technique for fabricating microstructures for biological applications, soft lithography overcomes many of the shortcomings of photolithography. In particular, soft lithography offers the ability to control the molecular structure of surfaces and to pattern the complex molecules relevant to biology, to fabricate channel structures appropriate for microfluidics, and to pattern and manipulate cells. For the relatively large feature sizes used in biology (≥50 μm), production of prototype patterns and structures is convenient, inexpensive, and rapid. Self-assembled monolayers of alkanethiolates on gold are particularly easy to pattern by soft lithography, and they provide exquisite control over surface biochemistry.

/pdf/soft-lithography-in-biology-and-biochemistry-1qiku7qz44.pdf

Soft Lithography in Biology and Biochemistry

Preface L.P. Kouwenhoven, et al. Introduction to Mesoscopic Electron Transport L.P. Kouwenhoven, et al. Geometric Phases in Mesoscopic Systems - From the Aharonov-Bohm Effect to Berry Phases A. Stern. Delocalization, Inelastic Scattering and Transport Due to Interactions Y. Imry. Electron Transport in Quantum Dots L.P. Kouwenhoven, et al. Magnetotunneling Spectroscopy: Studying Self-Organized Quantum Dots and Quantum Chaology L. Eaves. Shot Noise in Mesoscopic Systems M.J.M. de Jong, C.W.J. Beenakker. Admittance and Nonlinear Transport in Quantum Wires, Point Contacts, and Resonant Tunneling Barriers M. Buttiker, T. Chirsten. Transport Theory of Interacting Quantum Dots H. Schoeller. Transport in a One-Dimensional Luttinger Liquid M.P.A. Fisher, L.I. Glazman. The Proximity Effect in Mesoscopic Diffusive Conductors D. Esteve, et al. Mesoscopic Effects in Superconductivity R. Fazio, G. Schoen. Ultrasmall Superconductors D.C. Ralph, et al. The Superconducting Proximity Effect in Semiconductor-Superconductor Systems: Ballistic Transport, Low Dimensionality and Sample Specific Properties B.J. van Wees, H. Takayanagi. Scanning Probe Microscopes and Their Applications L.L. Soh, et al. Quantum Point Contacts Between Metals J.M. van Ruitenbeek. Conductance Quantization in Metallic Nanowires N. Garcia, et al. Quantum Optics Y. Yamamoto. Topics in Quantum Computers D.P. DiVincenzo.

Mesoscopic electron transport

Measuring the DNA content of eukaryotic cells is a fundamental task in biology and medicine. We have observed a linear relationship between the DNA content of eukaryotic cells and the change in capacitance that is evoked by the passage of individual cells across a 1-kHz electric field. This relationship is species-independent; consequently, we have developed a microfluidic technique-"capacitance cytometry"-that can be used to quantify the DNA content of single eukaryotic cells and to analyze the cell-cycle kinetics of populations of cells. Comparisons with standard flow cytometry demonstrate the sensitivity of this new technique.

https://www.pnas.org/content/pnas/97/20/10687.full.pdf

Capacitance cytometry: Measuring biological cells one by one

In this introductory chapter several basic concepts, relevant for mesoscopic electron transport, will be described. The aim is to provide a basis for several of the following Chapters of this volume. We, therefore, describe in the first Section various aspects of electron quantum transport in twodimensional electron gases. This includes an estimate of typical material parameters as well as comments on the fabrication. We then describe the quantization of the conductance in point contacts and the edge state picture of the Quantum Hall effect. In the second Section we describe the theory of single—electron tunneling in systems with strong charging and Coulomb-blockade effects. Here we restrict ourselves to the simplest case where low order perturbation theory is sufficient. We first discuss metallic low-capacitance junction systems and then indicate the relevant extensions when dealing with transport through quantum dots with discrete levels. Many further, equally important aspects of mesoscopic transport can not be covered here. Examples are interference and weak localization effects, level statistics or the many body description of solids. Fortunately, some of those will be covered in the more specialized Chapter of this volume.

/pdf/introduction-to-mesoscopic-electron-transport-3jjadieyy6.pdf

Introduction to Mesoscopic Electron Transport

Replica molding using polymeric materials: A practical step toward nanomanufacturing

We have used micromolding techniques to embed a nanoscale pore in PDMS. This novel design allows rapid and reproducible fabrication of pores, is extremely flexible, and can be modified both structurally and chemically for a variety of single-molecule detection applications. We demonstrate the capabilities of the device to sense electronically single DNA molecules.

Lydia L. Sohn

Papers

Mesoscopic electron transport

Capacitance cytometry: Measuring biological cells one by one

Introduction to Mesoscopic Electron Transport

Replica molding using polymeric materials: A practical step toward nanomanufacturing

An Artificial Nanopore for Molecular Sensing