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© 2017 Elsevier Inc. Microcalcifications (MCs) are routinely used to detect breast cancer in mammography. Little is known, however, about their materials properties and associated organic matrix, or their correlation to breast cancer prognosis. We combine histopathology, Raman microscopy, and electron microscopy to image MCs within snap-frozen human breast tissue and generate micron-scale resolution correlative maps of crystalline phase, trace metals, particle morphology, and organic matrix chemical signatures within high grade ductal carcinoma in situ (DCIS) and invasive cancer. We reveal the heterogeneity of mineral-matrix pairings, including punctate apatitic particles (<2 µm) with associated trace elements (e.g., F, Na, and unexpectedly Al) distributed within the necrotic cores of DCIS, and both apatite and spheroidal whitlockite particles in invasive cancer within a matrix containing spectroscopic signatures of collagen, non-collagen proteins, cholesterol, carotenoids, and DNA. Among the three DCIS samples, we identify key similarities in MC morphology and distribution, supporting a dystrophic mineralization pathway. This multimodal methodology lays the groundwork for establishing MC heterogeneity in the context of breast cancer biology, and could dramatically improve current prognostic models.

Skeletal metastases, the leading cause of death in advanced breast cancer patients, depend on tumor cell interactions with the mineralized bone extracellular matrix. Bone mineral is largely composed of hydroxyapatite (HA) nanocrystals with physicochemical properties that vary significantly by anatomical location, age, and pathology. However, it remains unclear whether bone regions typically targeted by metastatic breast cancer feature distinct HA materials properties. Here we combined high-resolution X-ray scattering analysis with large-area Raman imaging, backscattered electron microscopy, histopathology, and microcomputed tomography to characterize HA in mouse models of advanced breast cancer in relevant skeletal locations. The proximal tibial metaphysis served as a common metastatic site in our studies; we identified that in disease-free bones this skeletal region contained smaller and less-oriented HA nanocrystals relative to ones that constitute the diaphysis. We further observed that osteolytic bone metastasis led to a decrease in HA nanocrystal size and perfection in remnant metaphyseal trabecular bone. Interestingly, in a model of localized breast cancer, metaphyseal HA nanocrystals were also smaller and less perfect than in corresponding bone in disease-free controls. Collectively, these results suggest that skeletal sites prone to tumor cell dissemination contain less-mature HA (i.e., smaller, less-perfect, and less-oriented crystals) and that primary tumors can further increase HA immaturity even before secondary tumor formation, mimicking alterations present during tibial metastasis. Engineered tumor models recapitulating these spatiotemporal dynamics will permit assessing the functional relevance of the detected changes to the progression and treatment of breast cancer bone metastasis. Keywords: breast cancer; bone metastasis; bone mineral nanostructure; X-ray scattering; Raman imaging, National Institutes of Health (U.S.) (Grant R01CA173083), National Cancer Institute (U.S.) (Grant 1U54CA199081-01), National Cancer Institute (U.S.) (Grant 1U54CA210184-01)

A two-transistor active pixel image sensor (2T-APS) architecture is proposed. Instead of a reset transistor, a diode within the pinned photodiode sensor is used to reset the charge-sensing node in each pixel without any extra area. The new architecture can be used to increase the fill factor and/or reduce the pixel pitch. A test structure of the 2T-APS has been demonstrated using 0.35 μm CMOS technology featuring a 7μm x 7μm pixel size with a fill factor of 38%. The pixel characteristics are presented and discussed. ©2010 IEEE.

The subband current is evaluated by solving the non-equilibrium Green's function (NEGF) self-consistently with Poisson's equation for the double-gate MOSFETs with different channel lengths and thicknesses. The characteristics of subband current ratio and the details of subband number M are simulated, and the results show that the characteristics of current are determined by the first subband when TSi is smaller than 2.5nm, while the value of T Si is between 3.5nm and 5nm, the current of the second subband needs to be considered. The subband current ratios are highly related to the gate voltage, while less sensitive to the channel length. The suitable subband number M is also discussed for the devices with different sizes, which must be considered in balancing the model accuracy and the efficiency. © 2010 IEEE.

The heterodyne detection characteristics of field effect transistors are studied in this paper. Based on the hydrodynamic equations which govern the terahertz signal transport in field effect MOS transistors, a numerical simulation program is developed. This program works well in all operation regions of FETs from sub-threshold to strong inversion and from linear to saturation. The work demonstrates the potential to use MOS transistors for THz detectors and the method to optimize the device structure. Simulation results agree well with the existing theory in the nonresonant situations. ©2010 IEEE.

Impacts of parameter variations on the performance of double-gate (DG) tunneling FET (TFET) and conventional DG MOSFET are investigated by TCAD simulations. The different operation mechanisms determined their sensitivities to parameter variations. Variations in channel doping concentrations, gate oxide thickness, silicon film thickness and offset of gate electrode are studied in this work. It is found that though TFET overcomes the minimum subthreshold swing (SS) limit in conventional MOSFET, it is more sensitive to parameter variation, especially to gate oxide and silicon film thickness. © 2010 IEEE.

In this paper an analytic subthreshold potential model for undoped cylindrical gate-all-around (GAA) MOSFET with asymmetric gate underlap is developed. This model is derived by solving the Poisson's equation with the parabolic potential approximation, channel length transformation and conformai mapping. The analytic body center potential solution is presented. Compared with TCAD simulations, the proposed model shows good agreements, with different dimensions of the structure and varied bias conditions. The model here is appropriate for predicting the effect of gate misalignment or asymmetric gate underlap in GAA MOSFETs' design. © 2010 IEEE.

Energy bandstructures of unstrained and strained [100] silicon nanowires are calculated with nearest neighbor (NN) sp3d5s* tight binding model. Square nanowires with four {110} bounding facets of various thicknesses are simulated. It is found that bandgaps of nanowires increase with decreasing the wire thickness. Uniaxial strain effects are accounted for by displacing the silicon atoms and modifying the energy parameters in the tight binding model. The results indicate that both compressive and tensile strains reduce the bandgap and tensile strain reduces the hole effective mass at the valence band edge significantly. ©2010 IEEE.

In this paper a potential based model for monocrystalline silicon thin film transistor (TFT) systems on glass (SOG) substrate from the accumulation to the strong-inversion region is developed. By solving the complete dimensional (1D) Poisson's equation, the potential distribution in the channel is obtained. The analytic drain current is expressed accurately base on the potential solution. Compared with TCAD simulations, the proposed current model shows less than 1.05% errors, with the doping concentrations ranging from 1.5×10 16cm-3 to 1.5×1018cm-3 and different bias conditions. The proposed model is appropriate for precise and quick circuit simulation. ©2010 IEEE.

An empirical model for calculating the SET and RESET state resistance of phase change memory (PCM) is developed base on a resistor network method. The model has been extensively compared with numerical simulations with good accuracy. The model can be directly implemented into SPICE for simulating circuits with PCM elements.

This paper describes a web-based platform for nanoscale non-classical device modeling and circuit simulation, especially for non-classical CMOS device compact modeling and circuit performance prediction. This platform is based on program libraries, including model code files. We use SPICE as circuit simulation framework, and the Verilog-A as model design language. Based on the user input deck content, running embedding device and circuit programs, the platform produces several types of device characteristics output such as data texts and graphs on the web page for analysis, according to the simulation results and users' requests. Some nanoscale device modeling examples and the circuit simulation cases are demonstrated by the means of the platform configures and function application. It is shown that not only does this kind of platform address problems arising from the dependence on computer operating system of modeling and simulation software, the complexity of software and program update, but also helps researchers focus on their research on device physics and circuit design, display their research results and share latest research achievements or new technology online, which will accelerate the development of device modeling and circuit design technology in turn. © 2009 IEEE.

As one of the candidates of the next generation non-volatile memory(NVM), phase change memory(PCM) has been paid more attention. However, there are still many open issues such as numerical simulation to study. Phase transition is a temperature based process, which can be simulated by temperature profile generated by the device simulator coupled with the phase transition model. In this work, a phase transition model is implemented, which can provide the amorphization process simulation and the nucleation process simulation, and the set and reset process are simulated. Meanwhile the readout I-V characteristics are simulated and discussed.

This paper presents a charge-based compact model for the arbitrary doped long-channel cylindrical surrounding-gate (SRG) MOSFETs. Starting from Poisson's equation with fixed charge and inversion charge terms, an accurate equation of inversion charge is obtained with the full-depletion approximation. Substituting this inversion charge expression into Pao-Sah's dual integral, a drain current expression with concise form is derived. Based on the Ward-Dutton's linear-charge-partition method and the current continuity principle, all transcapacitances are obtained analytically. The developed model is valid in all operation regions without any smooth function. The model predictions have been extensively verified by 3D numerical simulations with a wide range of geometrical parameters and channel doping concentrations. © 2008 IEEE.