Survey on various architectures of preamplifiers for electroencephalogram (EEG) signal acquisition

Microsystem Technologies - Modern-day biomedical science and technology have progressed with implantable neural recording systems. There is a demand for miniaturised devices that can be emplaced...     

Recent Advances and Optimization Strategies on the Electrolytes for Hard Carbon and P-Based Sodium-Ion Batteries

Hard carbons (HCs) and P-based materials (including red phosphorus, black phosphorus, and metal phosphides) represent the most promising anodes for the commercialization of sodium ion batteries. The electrochemical performance of SIBs is determined not only by the structure of electrode materials, but it is also highly dependent on the matched electrolyte. In this review, the optimization, the matching strategies and the advanced characterization techniques of the electrolytes system for HCs and P-based anodes are discussed based on the recent advance. The effective optimization strategies are summarized from three aspects: sodium salts, solvents, and additives. The challenges and perspectives are also discussed in this review.     

Temperature dependent model for threshold voltage and subthreshold slope of strained-Si channel MOSFETs with a polysilicon gate

We present a temperature dependent model for the threshold voltage V_t and subthreshold slope S of strained-Si channel MOSFETs and validate it with reported experimental data for a wide range of temperature, channel doping concentration, oxide thickness and strain value. Such model includes the effect of lattice strain on material, temperature dependent effective mass of carriers, interface-trapped charge density and bandgap narrowing due to heavy channel doping. Also considered are polydepletion effects, carrier localization effect in the ultra-thin channel and quantum-mechanical effects. Our investigation reveals that the threshold voltage reduces linearly with increasing temperature whereas the subthreshold slope increases. In addition V_t is found to be sensitive to strain while S is weakly dependent on strain. Moreover, the channel doping concentration influences both V_t and S, and also the rate of change of V_t with temperature. Furthermore, S decreases for a lightly doped channel particularly at lower temperatures.     

Estimation of parameters of two-dimensional random amplitude chirp signal in additive noise

Multidimensional Systems and Signal Processing - In this paper, we consider a two-dimensional random amplitude chirp signal model. It is assumed that the additive error is independent and...     

Capillary driven flow in wettability altered microchannel

The capillary driven flow of water inside a microchannel with altered wettabilities is experimentally investigated and modeled theoretically. The surfaces of the PDMS made microchannel are exposed to oxygen plasma, rendering the surfaces increasingly hydrophilic, which provides the driving force for the flow. The plasma treated surfaces are characterized using topography and phase imaging of AFM scanning, as well as nano‐indentation, to correlate the distinct structural changes to the hydrodynamic profiles of the advancing meniscus. The experimental results are further analyzed using a newly proposed slip velocity model. The aim is to obtain a qualitative relationship between the surface properties and the flow parameters, namely the advancing meniscus velocity and pressure drop inside the channel. The insights are of fundamental importance in diverse fields, such as enhanced oil recovery, microfluidic devices, cell separation, and pathology. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4616–4627, 2017     

Emerging hiPSC Models for Drug Discovery in Neurodegenerative Diseases

Neurodegenerative diseases affect millions of people worldwide and are characterized by the chronic and progressive deterioration of neural function. Neurodegenerative diseases, such as Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington’s disease (HD), represent a huge social and economic burden due to increasing prevalence in our aging society, severity of symptoms, and lack of effective disease-modifying therapies. This lack of effective treatments is partly due to a lack of reliable models. Modeling neurodegenerative diseases is difficult because of poor access to human samples (restricted in general to postmortem tissue) and limited knowledge of disease mechanisms in a human context. Animal models play an instrumental role in understanding these diseases but fail to comprehensively represent the full extent of disease due to critical differences between humans and other mammals. The advent of human-induced pluripotent stem cell (hiPSC) technology presents an advantageous system that complements animal models of neurodegenerative diseases. Coupled with advances in gene-editing technologies, hiPSC-derived neural cells from patients and healthy donors now allow disease modeling using human samples that can be used for drug discovery.     

Development of noise model for InAsSb MOSFETs and their application in low noise amplifiers

Microsystem Technologies - In this paper, we develop the low frequency noise (LFN) model for symmetric double gate InAsSb channel n-MOSFETs and report noise performance of such devices as well as...