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

Detection of weak magnetic fields with nanoscale spatial resolution is an outstanding problem in the biological and physical sciences. For example, at a distance of 10 nm, the spin of a single electron produces a magnetic field of about 1 muT, and the corresponding field from a single proton is a few nanoteslas. A sensor able to detect such magnetic fields with nanometre spatial resolution would enable powerful applications, ranging from the detection of magnetic resonance signals from individual electron or nuclear spins in complex biological molecules to readout of classical or quantum bits of information encoded in an electron or nuclear spin memory. Here we experimentally demonstrate an approach to such nanoscale magnetic sensing, using coherent manipulation of an individual electronic spin qubit associated with a nitrogen-vacancy impurity in diamond at room temperature. Using an ultra-pure diamond sample, we achieve detection of 3 nT magnetic fields at kilohertz frequencies after 100 s of averaging. In addition, we demonstrate a sensitivity of 0.5 muT Hz(-1/2) for a diamond nanocrystal with a diameter of 30 nm.

Nanoscale magnetic sensing with an individual electronic spin in diamond

Light-Emitting Diodes. (Monographs in Electrical and Electronic Engineering.) By A. A. Bergh and P. J. Dean. Pp. viii+591. (Clarendon: Oxford; Oxford University: London, 1976.) £22.

/pdf/light-emitting-diodes-ubzde6g9qc.pdf

Light-emitting diodes

https://iopscience.iop.org/article/10.1088/1468-6996/16/2/023501/pdf

Recent progress on magnetic iron oxide nanoparticles: synthesis, surface functional strategies and biomedical applications.

In this review an overview about biological applications of magnetic colloidal nanoparticles will be given, which comprises their synthesis, characterization, and in vitro and in vivo applications. The potential future role of magnetic nanoparticles compared to other functional nanoparticles will be discussed by highlighting the possibility of integration with other nanostructures and with existing biotechnology as well as by pointing out the specific properties of magnetic colloids. Current limitations in the fabrication process and issues related with the outcome of the particles in the body will be also pointed out in order to address the remaining challenges for an extended application of magnetic nanoparticles in medicine.

Biological applications of magnetic nanoparticles

In this paper, we report on the fabrication and optoelectronic properties of high sensitive phototransistors based on few-layered MoSe2 back-gated field-effect transistors, with a mobility of 19.7 cm2 V−1 s−1 at room temperature. We obtained an ultrahigh photoresponsivity of 97.1 AW−1 and an external quantum efficiency (EQE) of 22 666% using 532 nm laser excitation at room temperature. The photoresponsivity was improved near the threshold gate voltage; however, the selection of the silicon dioxide as a gate oxide represents a limiting factor in the ultimate performance. Thanks to their high photoresponsivity and external quantum efficiency, the few-layered MoSe2-based devices are promising for photoelectronic applications.

https://iopscience.iop.org/article/10.1088/0957-4484/25/36/365202/pdf

High photosensitivity few-layered MoSe2 back-gated field-effect phototransistors.

/pdf/wide-bandgap-semiconductors-1deic9ziis.pdf

Wide Bandgap Semiconductors

Functionalized magnetic nanoparticles are important components in biorecognition and medical diagnostics. Here, we present a review of our contribution to this interdisciplinary research field. We start by describing a simple one-step process for the synthesis of highly uniform ferrite nanoparticles (d = 20-200 nm) and their functionalization with amino acids via carboxyl groups. For real-world applications, we used admicellar polymerization to produce 200 nm diameter 'FG beads', consisting of several 40 nm diameter ferrite nanoparticles encapsulated in a co-polymer of styrene and glycidyl methacrylate for high throughput molecular screening. The highly dispersive FG beads were functionalized with an ethylene glycol diglycidyl ether spacer and used for affinity purification of methotrexate-an anti-cancer agent. We synthesized sub-100 nm diameter magnetic nanocapsules by exploiting the self-assembly of viral capsid protein pentamers, where single 8, 20, and 27 nm nanoparticles were encapsulated with VP1 pentamers for applications including MRI contrast agents. The FG beads are now commercially available for use in fully automated bio-screening systems. We also incorporated europium complexes inside a polymer matrix to produce 140 nm diameter fluorescent-ferrite beads (FF beads), which emit at 618 nm. These FF beads were used for immunofluorescent staining for diagnosis of cancer metastases to lymph nodes during cancer resection surgery by labeling tumor cell epidermal growth factor receptor (EGFRs), and for the detection of brain natriuretic peptide (BNP)-a hormone secreted in excess amounts by the heart when stressed-to a level of 2.0 pg ml(-1). We also describe our work on Hall biosensors made using InSb and GaAs/InGaAs/AlGaAs 2DEG heterostructures integrated with gold current strips to reduce measurement times. Our approach for the detection of sub-200 nm magnetic bead is also described: we exploit the magnetically induced capture of micrometer sized 'probe beads' by nanometer sized 'target beads', enabling the detection of small concentrations of beads as small as 8 nm in 'pumpless' microcapillary systems. Finally, we describe a 'label-less homogeneous' procedure referred to as 'magneto-optical transmission (MT) sensing', where the optical transmission of a solution containing rotating linear chains of magnetic nanobeads was used to detect biomolecules with pM-level sensitivity with a dynamic range of more than four orders of magnitude. Our research on the synthesis and applications of nanoparticles is particularly suitable for point of care diagnostics.

https://iopscience.iop.org/article/10.1088/0957-4484/21/44/442001/pdf

Synthesis and applications of magnetic nanoparticles for biorecognition and point of care medical diagnostics

Development and Applications of Wide Bandgap Semiconductors.- Fundamental Properties of Wide Bandgap Semiconductors.- Photonic Devices.- Electronic Devices.- Novel Nano-Heterostructure Materials and Related Devices.- Crystal Growth.

Adarsh Sandhu

Papers

High photosensitivity few-layered MoSe2 back-gated field-effect phototransistors.

Wide Bandgap Semiconductors

Synthesis and applications of magnetic nanoparticles for biorecognition and point of care medical diagnostics

Wide Bandgap Semiconductors: Fundamental Properties and Modern Photonic and Electronic Devices

Preparation of size-controlled (30–100 nm) magnetite nanoparticles for biomedical applications