Applications, techniques, and microfluidic interfacing for nanoscale biosensing

Biosensors based on nanotechnology are rapidly developing and are becoming widespread in the biomedical field and analytical chemistry. For these nanobiosensors to reach their potential, they must be integrated with appropriate packaging techniques, which are usually based on nano/microfluidics. In this review we provide a summary of the latest developments in nanobiosensors with a focus on label-based (fluorescence and nanoparticle) and label-free methods (surface plasmon resonance, micro/nanocantilever, nanowires, and nanopores). An overview on how these sensors interface with nano/microfluidics is then presented and the latest papers in the area summarized.     

Structural study of titanium oxide films synthesized by ion beam-assisted deposition

The application of titanium dioxide (TiO(2)) films as surgical implant coatings for antibiotic attachment depends crucially on their available surface area and thus their surface morphology and crystallinity. Here, we report our fabrication of high Wenzel ratio TiO(2) films targeted to increase the film surface area using the ion beam-assisted deposition (IBAD) technique at high-deposition temperatures (approximately 610 degrees C). The modulation of the films' surface morphology was accomplished by varying the chemical identity of the concurrent ion beams bombarded on the films during the e-beam evaporation process. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were employed to investigate the surface morphology of the as-deposited films. X-ray diffractometry (XRD) revealed that these nanocrystalline films primarily consist of anatase phase TiO(2). Wenzel ratio, the ratio of the actual surface area to the projected area, of IBAD films prepared with argon, oxygen, and nitrogen ion beams was measured to be 1.52, 1.31 and 1.49, respectively. The effect of the differences in chemical reactivity and ion size of these three type ion beams are discussed to explain the present results.     

Object illumination angle measurement in speckle interferometry

Errors in measurement of the object illumination angle affect fringe interpretation accuracies in speckle interferometry. To measure the object illumination angle we propose a method based on the moiré effect. The technique is easy to implement and was found to yield fast and accurate measurements.     

White-light reconstruction setup for shearograms using optical-fiber waveguides

A white-light reconstruction setup for shearograms using optical-fiber waveguides is presented. The setup is compact, is not susceptible to dust and scratches, and enables the two-dimensional fringe pattern on shearograms to be viewed directly under uniform and enhanced illumination with minimal image distortion.     

Anatomically constrained electrical impedance tomography for anisotropic bodies via a two-step approach

Discusses the inclusion of anatomical constraints and anisotropy in static Electrical Impedance Tomography (EIT) using a two-step approach to EIT. In the first step, the boundaries between regions of different conductivities are anatomically constrained using Magnetic Resonance Imaging (MRI) data. In the second step, the conductivity values in different regions are determined. Anisotropic conductivity regions are included to allow better modeling of the muscle regions (e.g., skeletal muscle) which exhibit a greater conductivity in the direction parallel to the muscle fiber. This two-step approach is used to reconstruct the conductivity profile of a canine torso, illustrating its potential application in extracting conductivity values for bioelectric modeling.     

Erratum to: Charge transfer in graphene/polymer interfaces for CO2 detection

Nano Research - The order of the authors in the original version of this article was unfortunately incorrect on the first page and the first page of the ESM. Instead of Myungwoo Son1, Yusin Pak1,...     

Multiple circular-harmonic-function correlation filter providing specified response to in-plane rotation

The circular-harmonic-function correlation filter originally proposed by Hsu and Arsenault [Appl. Opt. 21, 4016 (1982)] for in-plane rotation invariance uses only one harmonic, which results in poor discrimination capability of the filter. Various methods to use multiple harmonics were explored previously by different researchers. We present a new method to combine multiple circular harmonics into a single filter that can provide the desired correlation response to in-plane rotation while minimizing the correlation-plane energy. Since multiple harmonics are included, the filter can discriminate well, and since correlation-plane energy is minimized, correlation peaks tend to be sharp. Since the designer can specify the desired in-plane rotation response, a variety of filter behaviors (including complete invariance to input rotations) can be obtained. Underlying theory is discussed, and simulation results are presented.     

Online scheduling on two parallel-batching machines with limited restarts to minimize the makespan

We study online scheduling on two unbounded parallel-batching machines with limited restarts to minimize the makespan. In this system jobs arrive over time and a batch can be restarted if and only if all the jobs in it have never been restarted. To tackle this difficult problem, we make the second-restart assumption whereby we can only interrupt a running batch B at time t if both machines are busy at time t and batch B has a later starting time than the other running batch. For this case, we provide a best online algorithm with a competitive ratio . For the general problem, we show that no online algorithms can have a competitive ratio less than 1.298, leaving a gap from 1.298 to 1.366.