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

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

The surface science of titanium dioxide

Nanocrystals are fundamental to modern science and technology. Mastery over the shape of a nanocrystal enables control of its properties and enhancement of its usefulness for a given application. Our aim is to present a comprehensive review of current research activities that center on the shape-controlled synthesis of metal nanocrystals. We begin with a brief introduction to nucleation and growth within the context of metal nanocrystal synthesis, followed by a discussion of the possible shapes that a metal nanocrystal might take under different conditions. We then focus on a variety of experimental parameters that have been explored to manipulate the nucleation and growth of metal nanocrystals in solution-phase syntheses in an effort to generate specific shapes. We then elaborate on these approaches by selecting examples in which there is already reasonable understanding for the observed shape control or at least the protocols have proven to be reproducible and controllable. Finally, we highlight a number of applications that have been enabled and/or enhanced by the shape-controlled synthesis of metal nanocrystals. We conclude this article with personal perspectives on the directions toward which future research in this field might take.

Shape‐Controlled Synthesis of Metal Nanocrystals: Simple Chemistry Meets Complex Physics?

Graphene’s success has shown that it is possible to create stable, single and few-atom-thick layers of van der Waals materials, and also that these materials can exhibit fascinating and technologically useful properties. Here we review the state-of-the-art of 2D materials beyond graphene. Initially, we will outline the different chemical classes of 2D materials and discuss the various strategies to prepare single-layer, few-layer, and multilayer assembly materials in solution, on substrates, and on the wafer scale. Additionally, we present an experimental guide for identifying and characterizing single-layer-thick materials, as well as outlining emerging techniques that yield both local and global information. We describe the differences that occur in the electronic structure between the bulk and the single layer and discuss various methods of tuning their electronic properties by manipulating the surface. Finally, we highlight the properties and advantages of single-, few-, and many-layer 2D materials in...

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Progress, Challenges, and Opportunities in Two-Dimensional Materials Beyond Graphene

We report on low-temperature scanning tunneling microscopy and spectroscopy measurements on NC-Ph3-CN molecules adsorbed at 300 K on a Cu(111) surface. Upon cooling, the molecules form chain and honeycomb structures, incorporating Cu adatoms supplied by the substrate as metal linkers. In these assemblies, the molecules align along two main directions, with a relative abundance that depends on the coordination number and on the bond length. We show spectroscopic data about the unoccupied molecular orbitals and investigate the patterns obtained by depositing different amounts of molecules. Comparison of these results with the ones obtained for NC-Ph5-CN molecules on the same substrate enables us to establish a hierarchy of the different interaction forces at work in the system.

/pdf/competing-interactions-in-the-self-assembly-of-nc-ph3-cn-2eo0shv11g.pdf

Competing Interactions in the Self-Assembly of NC-Ph3-CN Molecules on Cu(111)

Intermixing and two-dimensional alloy-formation in the Na/Au(111) system

We report on the magnetic properties of Fe and Co adatoms on a Cu2N/Cu(100)-c(2 x 2) surface investigated by x-ray magnetic dichroism measurements and density functional theory (DFT) calculations including the local coulomb interaction. We compare these results with properties formerly deduced from STM spin excitation spectroscopy (SES) performed on the individual adatoms. In particular we focus on the values of the local magnetic moments determined by XMCD compared to the expectation values derived from the description of the SES data. The angular dependence of the projected magnetic moments along the magnetic field, as measured by XMCD, can be understood on the basis of the SES Hamiltonian. In agreement with DFT, the XMCD measurements show large orbital contributions to the total magnetic moment for both magnetic adatoms.

/pdf/comparing-xmcd-and-dft-with-stm-spin-excitation-spectroscopy-44uqc587g3.pdf

Comparing XMCD and DFT with STM spin excitation spectroscopy for Fe and Co adatoms on Cu2N/Cu(100)

/pdf/magnetic-properties-of-ultrathin-fexco-1-x-films-on-pt-111-1x3tsu7al4.pdf

Harald Brune

Papers

Competing Interactions in the Self-Assembly of NC-Ph3-CN Molecules on Cu(111)

Intermixing and two-dimensional alloy-formation in the Na/Au(111) system

Comparing XMCD and DFT with STM spin excitation spectroscopy for Fe and Co adatoms on Cu2N/Cu(100)

Magnetic properties of ultrathin FexCo(1-x) films on Pt(111)

Pseudomorphic growth induced by chemical adatom potential