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

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

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

Diamond-like carbon (DLC) is a metastable form of amorphous carbon with significant sp3 bonding. DLC is a semiconductor with a high mechanical hardness, chemical inertness, and optical transparency. This review will describe the deposition methods, deposition mechanisms, characterisation methods, electronic structure, gap states, defects, doping, luminescence, field emission, mechanical properties and some applications of DLCs. The films have widespread applications as protective coatings in areas, such as magnetic storage disks, optical windows and micro-electromechanical devices (MEMs).

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Diamond-like amorphous carbon

Rapid progress in the synthesis and processing of materials with structure on nanometer length scales has created a demand for greater scientific understanding of thermal transport in nanoscale devices, individual nanostructures, and nanostructured materials. This review emphasizes developments in experiment, theory, and computation that have occurred in the past ten years and summarizes the present status of the field. Interfaces between materials become increasingly important on small length scales. The thermal conductance of many solid–solid interfaces have been studied experimentally but the range of observed interface properties is much smaller than predicted by simple theory. Classical molecular dynamics simulations are emerging as a powerful tool for calculations of thermal conductance and phonon scattering, and may provide for a lively interplay of experiment and theory in the near term. Fundamental issues remain concerning the correct definitions of temperature in nonequilibrium nanoscale systems. Modern Si microelectronics are now firmly in the nanoscale regime—experiments have demonstrated that the close proximity of interfaces and the extremely small volume of heat dissipation strongly modifies thermal transport, thereby aggravating problems of thermal management. Microelectronic devices are too large to yield to atomic-level simulation in the foreseeable future and, therefore, calculations of thermal transport must rely on solutions of the Boltzmann transport equation; microscopic phonon scattering rates needed for predictive models are, even for Si, poorly known. Low-dimensional nanostructures, such as carbon nanotubes, are predicted to have novel transport properties; the first quantitative experiments of the thermal conductivity of nanotubes have recently been achieved using microfabricated measurement systems. Nanoscale porosity decreases the permittivity of amorphous dielectrics but porosity also strongly decreases the thermal conductivity. The promise of improved thermoelectric materials and problems of thermal management of optoelectronic devices have stimulated extensive studies of semiconductor superlattices; agreement between experiment and theory is generally poor. Advances in measurement methods, e.g., the 3ω method, time-domain thermoreflectance, sources of coherent phonons, microfabricated test structures, and the scanning thermal microscope, are enabling new capabilities for nanoscale thermal metrology.

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Nanoscale thermal transport

Thermal reactions between aluminum and palladium layered films

Continuing improvement of microprocessor performance historically involves a decrease in the transistor size (device scaling). Device scaling allows greater device speed, an increase in device packing density, and an increase in the number of functions that can reside on a single chip. However, an increase in packing density requires an even larger increase in the number of interconnects that connect the devices together in an integrated circuit (IC). The interconnect packing density requirement has led to a reduction in the wiring pitch (sum of the metal line width and the spacing between the metal lines) to increase the wiring density. Unfortunately, as the interconnect wiring density increases so do the capacitance and the resistance. The larger capacitance causes the interconnect RC delay (or signal propagation delay), crosstalk, and power dissipation to all increase [1, 2, 3, 4, 5]. Models show that at device dimensions less than 0.25 µm (transistor gate length), the interconnect RC delay will begin to limit the overall chip performance. Thus, although the speed of the device increases as the feature size decreases, the interconnect delay becomes the major fraction of the total delay and limits the improvement in device performance [1,2,5,6].

Materials Issues and Characterization of Low- k Dielectric Materials

Ledge interactions and stress relaxations on Si(001) stepped surfaces.

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Thin Films and Interfaces

It is demonstrated that with proper analysis of the diffusion profiles, the effective charge and diffusivity for grain‐boundary electromigration can be separately measured. Electromigration profiles are analyzed based on Fisher‐type approximations for an equiaxial and perfectly textured grain structure. Electromigration profiles were obtained for Cu in Al at 255°C by measuring the spreading of a Cu cross‐stripe subject to a direct current; the results were checked by annealing experiments performed under similar conditions. Cu was observed to migrate in the direction of electron flow. Results obtained from analysis of the anode and annealing profiles are −16.8±1.2 for the effective charge and (1.75±0.12) × 10−14 cm3/sec for the diffusivity parameter αDbδ. The over‐all consistency of the results is better than 5%. Whipple analysis gives a more exact value of (2.74±0.16) × 10−14 cm3/sec for αDbδ.

Paul S. Ho

Papers

Thermal reactions between aluminum and palladium layered films

Materials Issues and Characterization of Low- k Dielectric Materials

Ledge interactions and stress relaxations on Si(001) stepped surfaces.

Thin Films and Interfaces

Grain‐boundary solute electromigration in polycrystalline films