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

The present invention provides stretchable, and optionally printable, semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed or otherwise deformed. Stretchable semiconductors and electronic circuits of the present invention preferred for some applications are flexible, in addition to being stretchable, and thus are capable of significant elongation, flexing, bending or other deformation along one or more axes. Further, stretchable semiconductors and electronic circuits of the present invention may be adapted to a wide range of device configurations to provide fully flexible electronic and optoelectronic devices.

http://science.sciencemag.org/content/sci/311/5758/208.full.pdf

Stretchable form of single crystal silicon for high performance electronics on rubber substrates

The present invention provides methods, systems and system components for transferring, assembling and integrating features and arrays of features having selected nanosized and/or microsized physical dimensions, shapes and spatial orientations. Methods of the present invention utilize principles of ‘soft adhesion’ to guide the transfer, assembly and/or integration of features, such as printable semiconductor elements or other components of electronic devices. Methods of the present invention are useful for transferring features from a donor substrate to the transfer surface of an elastomeric transfer device and, optionally, from the transfer surface of an elastomeric transfer device to the receiving surface of a receiving substrate. The present methods and systems provide highly efficient, registered transfer of features and arrays of features, such as printable semiconductor element, in a concerted manner that maintains the relative spatial orientations of transferred features.

Pattern Transfer Printing by Kinetic Control of Adhesion to an Elastomeric Stamp

The human eye is a remarkable imaging device, with many attractive design features. Prominent among these is a hemispherical detector geometry, similar to that found in many other biological systems, that enables a wide field of view and low aberrations with simple, few-component imaging optics. This type of configuration is extremely difficult to achieve using established optoelectronics technologies, owing to the intrinsically planar nature of the patterning, deposition, etching, materials growth and doping methods that exist for fabricating such systems. Here we report strategies that avoid these limitations, and implement them to yield high-performance, hemispherical electronic eye cameras based on single-crystalline silicon. The approach uses wafer-scale optoelectronics formed in unusual, two-dimensionally compressible configurations and elastomeric transfer elements capable of transforming the planar layouts in which the systems are initially fabricated into hemispherical geometries for their final implementation. In a general sense, these methods, taken together with our theoretical analyses of their associated mechanics, provide practical routes for integrating well-developed planar device technologies onto the surfaces of complex curvilinear objects, suitable for diverse applications that cannot be addressed by conventional means.

A hemispherical electronic eye camera based on compressible silicon optoelectronics

The present invention provides device components geometries and fabrication strategies for enhancing the electronic performance of electronic devices based on thin films of randomly oriented or partially aligned semiconducting nanotubes. In certain aspects, devices and methods of the present invention incorporate a patterned layer of randomly oriented or partially aligned carbon nanotubes, such as one or more interconnected SWNT networks, providing a semiconductor channel exhibiting improved electronic properties relative to conventional nanotubes-based electronic systems.

Medium scale carbon nanotube thin film integrated circuits on flexible plastic substrates

We have studied the so-called roof collapse in soft lithography. Roof collapse is due to the adhesion between the PDMS stamp and substrate, and it may affect the quality of soft lithography. Our analysis accounts for the interactions of multiple punches and the effect of elastic mismatch between the PDMS stamp and substrate. A scaling law among the stamp modulus, punch height and spacing, and work of adhesion between the stamp and substrate is established. Such a scaling law leads to a simple criterion against the unwanted roof collapse. The present study agrees well with the experimental data.

Stamp collapse in soft lithography.

Free-standing micro/nanoelements of single-crystal silicon with integrated doped regions for contacts provide a type of material that can be printed onto low-temperature device substrates, such as plastic, for high-performance mechanically flexible thin-film transistors (TFTs). We present simple approaches for fabricating collections of these elements, which we refer to as microstructured silicon (μs-Si), and for using spin-on dopants to introduce doped regions in them. Electrical and mechanical measurements of TFTs formed on plastic substrates with this doped μs-Si indicate excellent performance. These and other characteristics make the material potentially useful for emerging large area, flexible ‘macroelectronic’ devices.

Spin on dopants for high-performance single-crystal silicon transistors on flexible plastic substrates

Single-crystal organic semiconductors represent perfect systems not only for studying basic science associated with transport of polaronic charge carriers but also for investigating the upper limits of mobilities in thin-film organic devices for flexible displays and other emerging electronic applications. The field-effect transistor provides an important tool to explore the transport of field-induced charge carriers at the surface of organic semiconductors. [1] Special care, however, must be taken during the device fabrication to avoid degradation of the critical interface between the semiconductor and the dielectric. [2,3] High material purity, excellent crystalline quality, and nanoscale morphological smoothness are among the characteristics of this interface that are crucial to obtaining high-performance devices [4,5] and test structures for studies of intrinsic phenomena. Local surface measurements of organic semiconductors at the active interfaces of conventional transistors are difficult to perform, if not impossible, due to the inaccessibility of the semiconductor/gate dielectric interface by many classes of useful probes. [6–9] A new method for building transistors on the pristine surfaces of bulk single crystals uses free-space dielectrics (i.e., vacuum or air) to eliminate completely any contact or processing of the active surface of the semiconductor. [10] This technique, which provides a reversible ability to assemble and dissemble the devices repetitively, recently enabled observation of intrinsic transport and transport anisotropy in rubrene. [10,11] Other groups, using different techniques,

Nanoscale Surface Morphology and Rectifying Behavior of a Bulk Single‐Crystal Organic Semiconductor

A large-format substrate with distributed control elements is formed by providing a substrate and a wafer, the wafer having a plurality of separate, independent chiplets formed thereon; imaging the wafer and analyzing the wafer image to determine which of the chiplets are defective; removing the defective chiplet(s) from the wafer leaving remaining chiplets in place on the wafer; printing the remaining chiplet(s) onto the substrate forming empty chiplet location(s); and printing additional chiplet(s) from the same or a different wafer into the empty chiplet location(s).

High-Yield Fabrication of Large-Format Substrates with Distributed, Independent Control Elements

A substrate includes an anchor area (30) physically secured to a surface of the substrate (10) and at least one printable electronic component (20). The at least one printable electronic component includes an active layer (14) having one or more active elements thereon, and is suspended over the surface of the substrate by electrically conductive breakable tethers (40). The electrically conductive breakable tethers include an insulating layer and a conductive layer thereon that physically secure and electrically connect the at least one printable electronic component to the anchor area, and are configured to be preferentially fractured responsive to pressure applied thereto. Related methods of fabrication and testing are also discussed.

Etienne Menard

Papers

Stamp collapse in soft lithography.

Spin on dopants for high-performance single-crystal silicon transistors on flexible plastic substrates

Nanoscale Surface Morphology and Rectifying Behavior of a Bulk Single‐Crystal Organic Semiconductor

High-Yield Fabrication of Large-Format Substrates with Distributed, Independent Control Elements

Structures and methods for testing printable integrated circuits