Enhanced bactericidal action and masking of allergen structure of soy protein by attachment of chitosan through Maillard‐type protein‐polysaccharide conjugation

The soy protein‐chitosan conjugate was formed by the Maillard reaction in dry state (relative humidity 65%) at 60°C for 2 weeks to improve the functional properties. The antimicrobial activity of the Maillard‐type soy protein‐chitosan conjugates enhanced 2–3 times that of soy protein‐chitosan mixture. The soy protein‐chitosan conjugate showed excellent emulsifying property with the progress of Maillard‐type conjugation. The allergenicity of soy protein was greatly decreased by the attachment of chitosan through Maillard reaction. The immonoblotting analysis with patient's sera revealed that soy protein‐chitosan conjugate was more effective to mask the allergen structure of soy protein causing from 34 kDa‐protein (Gly m Bd 30K) than soy protein‐galactomannan conjugate. The Western blotting showed that allergen (34 kDa‐protein) was completely masked by soy protein‐chitosan conjugation, while it was not completely masked by soy protein‐galactomannan conjugation.     

Real-time loop-mediated isothermal amplification for the CaMV-35S promoter as a screening method for genetically modified organisms

A method has been developed to detect genetically modified organisms (GMOs). The detection method is based on the loop-mediated isothermal amplification (LAMP) reaction. Cauliflower mosaic virus 35S (CaMV-35S) promoter gene, a widespread genetic element, was amplified by a set of LAMP primers. One of the characteristics of the LAMP method is its ability to synthesize an extremely large amount of DNA. Accordingly, a large amount of byproduct, pyrophosphate ion, is produced, yielding a white precipitate of magnesium pyrophosphate in the LAMP reaction mixture. The measurement of the turbidity of the reaction mixture allows easy detection of amplification of CaMV-35S promoter gene without the need for gel electrophoresis. With this new technique we analyzed Roundup Ready soybean, and found GMO content ranging from 0.5% to 5%.     

Acetic acid treatment for wrinkle‐free oral mucosal epithelia in paraffin section preparation

For histopathological assessment of oral borderline malignancies, it is important to carefully detect subtle epithelial changes on fully stretched tissue sections. However, it is not generally easy to obtain wrinkle‐free sections when using formalin‐fixed paraffin‐embedded oral mucosal samples. Since acetic acid treatment is already utilized for large brain tissue sections, we examined whether that treatment was also effective for oral mucosal tissues containing normal to malignant epithelial lesions. Paraffin sections were floated in various concentrations of acetic acid for 10 min after stretching in water for 1 min, then wrinkle formations were examined using hematoxylin and eosin staining, as well as for staining intensity with keratin immunohistochemistry. Wrinkles were formed in both epithelial and connective tissue zones of sections treated with less than a 40‐mM (0.25%) concentration of acetic acid. In contrast, treatments with concentrations at 80 mM (0.5%) and higher resulted in cracking between the epithelial layer and lamina propria, as well as poor immunohistochemical results for keratins 13 and 17, even though the wrinkles completely disappeared. These results indicate that 40 mM is the optimal concentration of acetic acid solution to prevent wrinkles in the epithelial layer while maintaining the immunohistochemical qualities of oral mucosa tissue sections, especially those containing borderline malignant epithelial lesions. Microsc. Res. Tech., 2010. © 2010 Wiley‐Liss, Inc.     

A Study on the Utilization of Magnetite for the Recovery of Platinum Group Metals from Chloride Solution

The recovery of platinum group metals (PGMs) from chloride solution using magnetite was investigated. The adsorption of platinum, palladium, and rhodium in chloride medium onto synthetic magnetite powders were studied at different pH conditions, contact time, sodium chloride concentrations, and initial Pt, Rh, and Pd concentrations. Platinum and palladium uptake by magnetite was at a maximum at pH 6–7, and pH 3–4 for rhodium after 24 h with 0.1 mol/dm³ sodium chloride at an initial PGM concentration of 0.05 mol/m³. A sorption mechanism for PGMs was discussed based on the results.     

Post-manufacturing, 17-times acceptable raw bit error rate enhancement, dynamic codeword transition ECC scheme for highly reliable solid-state drives, SSDs

A dynamic codeword transition ECC scheme is proposed for highly reliable solid-state drives, SSDs. By monitoring the error number or the write/erase cycles, the ECC codeword dynamically increases from 512 Byte (+parity) to 1 KByte, 2 KByte, 4 KByte…32 KByte. The proposed ECC with a larger codeword decreases the failure rate after ECC. As a result, the acceptable raw bit error rate, BER, before ECC is enhanced. Assuming a NAND Flash memory which requires 8-bit correction in 512 Byte codeword ECC, a 17-times higher acceptable raw BER than the conventional fixed 512 Byte codeword ECC is realized for the mobile phone application without an interleaving. For the MP3 player, digital-still camera and high-speed memory card applications with a dual channel interleaving, 15-times higher acceptable raw BER is achieved. Finally, for the SSD application with 8 channel interleaving, 13-times higher acceptable raw BER is realized. Because the ratio of the user data to the parity bits is the same in each ECC codeword, no additional memory area is required. Note that the reliability of SSD is improved after the manufacturing without cost penalty. Compared with the conventional ECC with the fixed large 32 KByte codeword, the proposed scheme achieves a lower power consumption by introducing the “best-effort” type operation. In the proposed scheme, during the most of the lifetime of SSD, a weak ECC with a shorter codeword such as 512 Byte (+parity), 1 KByte and 2 KByte is used and 98% lower power consumption is realized. At the life-end of SSD, a strong ECC with a 32 KByte codeword is used and the highly reliable operation is achieved. The random read performance is also discussed. The random read performance is estimated by the latency. The latency is below 1.5 ms for ECC codeword up to 32 KByte. This latency is below the average latency of 15,000 rpm HDD, 2 ms.     

Position Dependent Response of Superconducting MgB2 Neutron Detectors Studied by Pulsed Laser Irradiation

The MgB₂ detector consists of 200?nm thick MgB₂ thin film meander structure of 3?μm line width protected by 300?nm thick SiO layer. The electrical connections were provided by 150?nm thick Nb. The devices were placed in a 4?K refrigerator to investigate the behavior at temperatures below T _c. The position-dependent response of the MgB₂ detector can be investigated by scanning a laser spot with the aid of the XYZ piezo-driven stage and an optical fiber with a focusing lens. We found that the inhomogeneity in a detector is very critical to specify the detection efficiency since the detector has the sensitivity only in a narrow temperature regime near T _c.