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This paper presents an experimental result to identify the bond behavior of head-splice-sleeve (HSS) with the consideration of several design factors as variables. In addition, it attempts to investigate strength evaluation method in consideration of the bearing effect caused by head attached to the bar and the bond strength between the embedded bar and grout mortar. As a result, the HSS specimen without head underwent a brittle mortar failure before yielding while the HSS specimens with suitable head size showed sufficient ductile behavior and rebar failure at the end. It was contributed to the bearing action of the head inside sleeve. From the analysis on the effect of head size, it was recommended that a suitable diameter ratio between head and bar is 1.3 for the design purpose. In addition, a proper design process was proposed for the HSS based on the test result and it was found that the ratio of test result and calculation result obtained by the equation ranged from 0.99 to 1.10 and the average ratio was 1.01. From this, it can be said that the strength of HSS with standard head size is suitably predicted by using the proposed equation.

The haptic sense is one of the five human senses that deeply affects cognitive development and everyday lives of children and adults. Recently, researchers and developers have started active discussions and research on haptic technologies. The purpose of this paper is to explain the role of haptics in learning, review studies that have attempted to use haptic technologies to teach students, and discuss how these technologies can be applied in special education context. National and international databases were searched and analyzed using meta-analysis methods. The few studies that have been completed so far are heavily focused on math and science learning. However, haptic technology has great potentials for children with disabilities who can benefit from extra assistance from these devices in wide areas of curriculum including math, science, music, art, history, and so on.

High performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC/MS) have been widely used to quantify aflatoxins in food, but these methods are expensive, time-consuming, unsuitable for analysis of the routine screening of large sample numbers and require derivatization and high level techniques to perform. The objective of this study is to detect aflatoxins in a large number of foods by a high efficient analytical system of combined enzyme linked immunosorbent assay (ELISA) for screening and LC/MS/MS for confirmation. The samples spiked individually with aflatoxin (0.5 and 1.0 ng/g) and total aflatoxins (10 ng/g) were analyzed by ELISA and LC/MS/ MS, and the recoveries for ELISA and LC/MS/MS were 71.8~119.2% and 70.8~135.3%, respectively. A total of 378 samples (grains, nuts, soybean and fermented soybean foods, pepper and fermented pepper foods) were purchased from the six major cities in Korea and analyzed by ELISA-LC/MS/MS system. Twenty two (5.8%; peanut: 11, pistachio: 2, walnut: 6, almond: 1, pepper powder: 1, pepper paste: 1) out of 378 samples were screened as aflatoxin B1 positive by ELISA, but, 4 (1.1%; peanut: 2, pistachio:1, pepper powder: 1) out of the 22 samples screened were confirmed as aflatoxins positive at levels of 1.02~52.79 ng/g by LC/MS/MS. ELISA-LC/MS/MS system provides a more rapid, accurate and cost-effective method for the detection of aflatoxins in large number of samples.

A fluorescence polarization immunoassay (FPIA) for the quantitative determination of 6-chloronicotinic acid (6-CNA) using polyclonal antibody was developed. The 6-CNA-protein (bovine serum albumin and soybean trypsin inhibitor) conjugates and fluorescein-labeled 6-CNA derivative (tracer) were prepared and used as the immunogens and tracer, respectively. The synthesized tracer was purified by thin layer chromatography (TLC) and showed a good binding to antiserum (73/5) which was obtained from the immunized rabbit (No. 73) with 6-CNA-BSA conjugate. The detection limit (10% inhibition) of FPIA was 4 microg/mL, and IC(50) value was 32 microg/mL. The FPIA showed a cross-reaction for 5-amino-2-chloropyridine (60%), but no cross-reaction for other pesticides was observed. Recoveries for spiked apple, urine, soil, and water samples (5, 50, and 500 ppm) averaging between 78.6 +/- 8.8 and 114 +/- 18% were reasonable and in good agreement with the amounts spiked. Although the developed FPIA possesses low sensitivity, this assay is more simple and quick than other analytical methods, such as high performance liquid chromatography and gas chromatography. Thus, the developed FPIA method could be a useful tool for express screening 6-CNA in agricultural, environmental, and biological samples.