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Cardiovascular diseases (CVDs) cause more than 17 × 106 deaths worldwide on a yearly basis. Early diagnosis of CVDs is therefore of great need. The C-reactive protein (CRP) is an important biomarker for analyzing the risks of CVDs. In this work, CRP-specific aptamers with high sensitivity and specificity and field-effect-transistor (FET) devices were used to recognize and detect CRP by using an integrated microfluidic system automatically while consuming less volumes of reagents and samples (about 5 μm). In order to package the FET device into the microfluidic chip, a new method to prevent liquid leakage was proposed. Sensitive detection of CRP has been demonstrated on the developed microfluidic system. It is the first time that aptamer-FET assays could be realized on an integrated microfluidic system. Experimental results showed that the aptamer-FET assay was capable of detecting CRP with concentrations ranging from 0.625 mg/l to 10.000 mg/l, which may be promising for early diagnosis of CVDs.

Rapid and accurate diagnosis of C-reactive protein (CRP) is crucial for monitoring cardiovascular diseases because it is a well-known biomarker for evaluating risks of cardiovascular diseases. This study presents a dual-aptamer assay for detection of CRP by using field-effect transistors (FET). This is the first time that two aptamers, which are specific to CRP, were used to form a sandwich assay such that the CRP concentration could be detected by FET devices. Furthermore, a microfluidic system was used to automate the dual-aptamer sandwich assay such that the entire diagnosis process could be automated. In addition to electric signals from the FET device, fluorescent signals were also used to confirm this assay. Experimental results revealed that the first aptamer (1st aptamer) and the second aptamer (c aptamer) could be specifically binded with target CRP. Furthermore, the microfluidic chip integrated with FET can be re-used if the binded CRP and 2nd aptamer was eluted. Besides, in order to prevent the interference materials like proteins, cells and any nonspecific molecules from adhering onto the gate region of the FET device even after immobilization of 1st aptamer, we used ethanolamine as the blocking agent to prevent nonspecific adhesion. The experimental results confirmed that blocking using ethanolamine could successfully prevent nonspecific binding.

Viewing urbanization as a change in the source and amount of energy flows from rural background to urban core provides a biophysical perspective of urban development. In this paper we begin by applying energetic principles to an urban setting and relating them to spatial hierarchy. Based on past research in urban energy theory and system modeling, we developed a spatial model to simulate the evolving spatial hierarchy of an urban system due to changing energy flows. Using an energy systems diagram, the spatial unit model consists of three interacting subsystems – natural area, agricultural area and urban area – representing a simplified entity or unit model of each grid element within a city-region. The Taipei metropolitan region is used as an example and is divided into grids of 1 km × 1 km to reveal the spatial heterogeneity of the urban landscape system. The spatial simulation was performed using geographical information system (GIS) and the model results show an increase in the urban energy hierarchy and reveal a pattern of spatial convergence. The energetic mechanisms of the evolving spatial hierarchy of the urban landscape system are discussed.

A new full-field 3-D micro surface profilometer using digital micromirror device (DMD)-based fringe projection strategy and confocal principle is presented in the article. In viewing the fact that conventional laser confocal measurement method not only easily encounters undesired irregular scattering problems, but also lack scanning efficiency due to its single-point type measurement, the newly developed automatic surface profilometer deploys a DMD chip to project spatially encoded digital fringe patterns with dynamic light intensity, onto the object to obtain excellent measurement performance. A novel digital fringe pattern design with adaptive sinusoidal intensity modulation was developed for active fringe projection, to obtain optimized depth resolution with a micrometer lateral resolution in confocal measurement. Some of semiconductor components have been measured to attest the feasibility of the developed approach. The depth measurement resolution can reach better than 0.1μm and the maximal measured error was verified to be less than less than 0.5 % of the measured step size.

Intelligent surveillance systems have become an important research issue recently. They can provide an early warning or help us to retrieve interested video frames. The motion detection techniques play an important role in these two applications. In this paper, we propose an effective surveillance video retrieval method based upon the motion detection technology. We can use this method to search frames with moving objects. We also use the feature, motion vectors, to retrieve the frames with objects in pre-defined moving directions. We use video samples to show the feasibility of our method.