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Polystyrene (PS) is the most commonly used material in cell culture devices, such as Petri dishes, culture flasks and well plates. Micropatterning of cell culture substrates can significantly affect cell-material interactions leading to an increasing interest in the fabrication of topographically micro-structured PS surfaces. However, the high stiffness combined with brittleness of PS (elastic modulus 3-3.5 GPa) makes high-quality patterning into PS difficult when standard hard molds, e.g. silicon and nickel, are used as templates. A new and robust scheme for easy processing of large-area high-density micro-patterning into PS film is established using nanoimprinting lithography and standard hot embossing techniques. Including an extra step through an intermediate PDMS mold alone does not result in faithful replication of the large area, high-density micropattern into PS. Here, we developed an approach using an additional intermediate mold out of OrmoStamp, which allows for high-quality and large-area micro-patterning into PS. OrmoStamp was originally developed for UV nanoimprint applications; this work demonstrates for the first time that OrmoStamp is a highly adequate material for micro-patterning of PS through hot embossing. Our proposed processing method achieves high-quality replication of micropatterns in PS, incorporating features with high aspect ratio (4:1, height:width), high density, and over a large pattern area. The proposed scheme can easily be adapted for other large-area and high-density micropatterns of PS, as well as other stiff and brittle polymers. (C) 2016 Elsevier B.V. All rights reserved.

Histone modification and chromatin remodeling are important events in response to DNA damage, and Polycomb group (PcG) proteins, catalyzing H3K27 methylation, are involved. However, the biological function and mechanism of PcG in DNA damage are not fully understood. Additionally, downstream effectors in hepatocellular carcinoma (HCC) remain unclear. The present study investigated the biological and mechanistic roles of PcG in the DNA damage response induced by chemotherapeutic drugs in HCC. It was found that chemotherapy drugs, such as epirubicin (EPB) and mitomycin C (MMC), effectively blocked expression of PcG in p53-wild-type HepG2 cells but not in PLC/PRF5 and Hep3B cells with p53 mutation or deletion. PcG-related target genes involved in DNA damage were identified, including p53, Ataxia telangiectasia mutated (ATM) and Forkhead box O3 (FOXO3). Moreover, targeting PcG-induced p53 expression was associated with increased drug sensitivity in HCC cells. shRNA targeting enhancer of zeste homolog 2 (EZH2) or its inhibitor GSK126 significantly promoted chemotherapeutic drug-induced genotoxicity and increased HepG2 cell chemosensitivity. Mechanistically, chromatin immunoprecipitation (ChIP) assays confirmed that PcG binds to the ATM promoter and inhibits its expression through covalent modification of H3K27me3. Herein, we establish a potential chemotherapy association with GSK126, and the findings suggest this link might represent a new strategy for increasing the sensitivity of HCC to chemotherapeutic agents.

This is a feasibility study of the design and construction of a metal detector system using a fiber-optic Mach–Zehnder interferometer and a sensor employing a novel polymeric magnetostrictive material. This ferromagnetic polymeric metal detector system is small and easy to fabricate, offering relatively high sensitivity and resistance to the radio frequency interference common in most electromagnetic metal detectors. The metal detection is achieved by disrupting the magnetic flux density that encompasses the magnetostrictive sensor. This article discusses the magnetic properties of the ferromagnetic polymers and the results of detecting metal objects of different shapes and geometries.

In order to evaluate the present state of teachers’ professional identity (TPI), 177 teachers in primary and secondary schools in Zibo of Shandong Province of China were surveyed by a questionnaire designed by the authors. The results reveals: (1) high professional identity for the overall level of teachers; (2) significant difference in genders and titles of professional positions; (3) significant difference between primary and secondary school teachers; (4) significant difference in professional motivations and satisfaction degrees of salaries among teachers.

This paper presents a new metal detector using a fiberoptic magnetostriction sensor. The metal sensor uses a fiber-optic Mach-Zehnder interferometer with a newly developed ferromagnetic polymer as the magnetostrictive sensing material. This polymeric magnetostrictive fiberoptic metal sensor is simple to fabricate and small in size. In contrast to electromagnetic type metal detectors, this fiber optic metal sensor is resistant to RF interference. Metal detection is based on disruption of the magnetic flux de nsity across the magnetostriction sensor. In this paper, characteristics of the material being sensed and magnetic properties of the ferromagnetic polymers will be discussed.

This paper describes the design and construction of a magnetostrictive composite-fiber-optic Mach-Zehnder interferometer capable of magnetic field and metal profile measurement. Unlike previous metal detectors, the sensor makes use of the magnetostriction effect on a fiber-optic interferometer to detect metallic objects. The metal detector overcomes many difficulties existing in conventional metal detectors. Aside from offering relatively high sensitivity (sensitivity of about 70.7 × 10−3 rad/gauss), the optical detection provides resistance to RF interference which is common in typical electromagnetic type metal detectors. The magnetostrictive sensor is also relatively compact and able to achieve a minimum spatial resolution of 1 cm2 for metal profile detection.

The purpose of this paper is to develop a novel ferromagnetic polymeric metal detector system by using a fiber-optic Mach-Zehnder interferometer with a newly developed ferromagnetic polymer as the magnetostrictive sensing device. This ferromagnetic polymeric metal detector system is simple to fabricate, small in size, and resistant to RF interference (which is common in typical electromagnetic type metal detectors). Metal detection is made possible by disrupting the magnetic flux density present on the magnetostrictive sensor. This paper discusses the magnetic properties of the ferromagnetic polymers. In addition, the preliminary results of successful sensing of different geometrical metal shapes will be discussed.

As sensors become integrated in more applications, interest in magnetostrictive sensor technology has blossomed. Magnetostrictive materials have many advantages and useful applications in daily life, such as high efficient coupling between elastic and polymer material, large displacement, magnetic field sensors, micro actuator and motion motor, etc. The purpose of this paper is to develop a metal sensor which is capable of detecting different geometries and shapes of metal objects. The main configuration is using a Mach-Zehnder fiber-optic interferometer coated with magnetostrictive material. The metal detector system is a novel design of metal detector, easy to fabricate and capable of high sensitivity. In our design, metal detection is made possible by disrupting the magnetic flux density that encompasses the magnetostriction sensor. In this paper, experimental setups are described and metal sensing results are presented. The results of detecting complex metal's geometry and metal's mapping results are discussed.

The purpose this paper is the development a novel polymeric fiber-optic magnetostrictive metal detector, using a fiber-optic Mach-Zehnder interferometer and polymeric magnetostrictive material. Metal detection is based on the strain-induced optical path length change steming from the ferromagnetic material introduced in the magnetic field. Varied optical phase shifts resulted largely from different metal objects. In this paper, the preliminary results on the different metal material detection will be discussed.

A polymeric magnetostrictive fiber-optic sensor is presented. The sensor uses a newly developed ferromagnetic polymer (WCS-NG1) as the magnetostrictive coating for magnetic field detection. A simple fiber-optic Mach-Zehnder interferometer is deployed; where magnetic field induced magnetostriction effect is detected based on the phase modulation measurement. The magnetostrictive effect has a number of advantages of sensor. It is relatively simple to fabricate on the optical fiber. Optical technique also provides high sensitivity in its measurant. Therefore, magnetostrictive effect is used for the fiber optics magnetometer. Comparison with Tefonol or other conventional magentistrcition sensors, this novel polymeric magnetostrictive fiber-optic sensor is much less complex relatively smaller in size, and optical technique also prevents RF interference that is common in typical electromagnetic type sensors. In this paper, characterization of the material and magnetic properties of the embedded polymer will be discussed. Preliminary results on the magnetic field and current sensing will be presented.

Many small scale image display systems, such as head mounted displays (HMDs), beam light from an optical fiber onto deflectable mirrors or rotating polygonal mirrors to produce an image on an image plane. This approach has many size limitations. For instance, light beams of less than 3 millimeters are impractical for displays using mirrors, because mirror scanners and grating deflectors must be significantly larger than the light beam diameter to avoid beam clipping or adding diffraction. Reducing the diameter of a conventional display device reduces the possible number of pixels, and thus reduces the resolution and/or field of view (FOV) of the device. Our proposed HMD system focus on reducing the hardware while maintaining a high resolution by utilizing a microfabricated 2D optical scanner combined with a field-programmable gate array (FPGA) controller for display.