Detection of irradiated meat, fish and their products by measuring 2-alkylcyclobutanones levels after frozen storage

2-Alkylcyclobutanones, such as 2-dodecylcyclobutanone and 2-tetradecylcyclobutanone, were analyzed to assess the irradiation history of irradiated meats or fish, and cooked foods with irradiated ingredients, which had been stored frozen for up to one year. The purpose of the study was to show that irradiated meats could be detected even after having been stored in the distribution system. 2-Alkylcyclobutanones showed a small decrease in irradiated raw meats that had been stored frozen for one year. Cooked foods, such as pancake and fried chicken made with irradiated eggs and chicken, respectively, contained detectable levels of 2-alkylcyclobutanones after storage frozen for one year. The 2-alkylcyclobutanones became undetectable in highly dried samples, such as feed for lab animals, during the same period.     

Carboxylated polysulfone membranes having a chiral recognition site induced by an alternative molecular imprinting technique

SUMMARY Molecularly imprinted polymeric membranes were prepared from carboxylated polysulfone. Membranes imprinted by Z-D-Glu recognize the D-isomer in preference to the corresponding L-isomer, and vice versa. The amino acid preferentially adsorbed by the membrane was also selectively permeated by electrodialysis. Received: 22 January 1998/Accepted: 20 February 1998     

X-ray diffraction reciprocal space and pole figure characterization of cubic GaN epitaxial layers grown on (0 0 1) GaAs by molecular beam epitaxy

X-ray diffraction reciprocal space maps and pole figures were used to analyse the cubic GaN epitaxial layers grown on (0 0 1) GaAs by r.f. plasma source MBE; the presence of hexagonal phase in cubic GaN layers was detected by high resolution x-ray analysis and the relationships among various crystal axes of cubic and hexagonal phase GaN were analysed with respect to V/III source-supply ratio. As for the growth conditions of the epitaxial layers, the V/III ratio was found to drastically affect the quality of the layers. High-temperature growth under near-stoichiometric conditions was necessary to obtain high quality epitaxial layers. It was found that inclusion of the hexagonal phase in the cubic GaN layers could be less than 0.4%, though previously reported typical c-GaN epitaxial layers included as much as 10–20% hexagonal phase GaN. On the basis of the measurements and analyses of reciprocal space maps and pole figures, it was revealed that the orientation of crystal axes of the hexagonal phase was unique in the present GaN epitaxial layers and they were different from those of previously reported c-GaN epitaxial layers.     

Development of a Kanji (Chinese Characters) Instruction Tool by Using Image-Processing Aided Method

Nowadays, it is quite easy to read or write kanji, that is Chinese character, by. writingthem on the computer monitor tube and/or word processor on screen. On the other hand, their realmeanings or history as they have originated and developed can not always be understood by theJapanese people.Moreover, any kanji today is often used only as a symbol without other meaning, andmeaningless words otherwise than their pronunciations are prevalent;which trend trend should never besupported by the public in general.In this study, we propose a system of educational tools for presenting kanji characters to let thestudents understand meanings of them as they originated from their prototypes or hieroglyphicimages representing their original meanings. The key frame or interval figure method is one ofeffective methods in computer graphic (CG) to show the transition of one original figure (A) to itscurrent form (B). Using this method is considered very effective when kanji is usually written ordisplayed in straight lines and curves. However, sometimes and kanji is also written or drawn like apicture with a special pen or a Japanese fude () to make adequate a main auxiliary techniquecalled morphing introduced in this study. Several examples in point are demonstrated on the videotape at the conference.     

“Nata Puree,” a Novel Food Material for Upgrading Vegetable Powders,Made by Bacterial Cellulose Gel Disintegration in the Presence of (1,3)(1,4)-β-Glucan

Pulverization is a potentially powerful solution for the resource management of surplus- and non-standard agricultural products, maintaining their nutritional values for long and ensuring their homogeneity, whereas their original textures could disappear to narrow the application ranges. Therefore, new technologies should be developed for reconstructing the powders to provide them with new physical characteristics. Herein, we developed a novel food material, nata puree (NP), by nata de coco (bacterial cellulose gel) disintegration with a water-soluble polysaccharide using a household blender. The process worked well with (1,3)(1,4)-β-glucan (BGL) as the polysaccharide, which could be substituted with barley extract. Lichenase treatment of the NP dramatically modified its physical properties, suggesting the importance of the BGL polymeric forms. NP exhibited distinct potato powder and starch binding activities, which would be attributed to its interactions with the cell wall components and a physical capture of powders by the NP network, respectively. NP supplementation into the potato paste improved its firmness and enabled its printable range shift for 3D food printing to a lower powder-concentration. NP also promoted the dispersion of powders in its suspension, and designed gelation could also be successfully performed by the laser irradiation of an NP suspension containing dispersed curdlan and turmeric powders. Therefore, NP could be applied as a powder modifier to a wide range of products in both conventional cooking, food manufacturing, and next generation processes such as 3D food printing.     

Comparing the Osteogenic Potential and Bone Regeneration Capacities of Dedifferentiated Fat Cells and Adipose-Derived Stem Cells In Vitro and In Vivo: Application of DFAT Cells Isolated by a Mesh Method

Background: We investigated and compared the osteogenic potential and bone regeneration capacities of dedifferentiated fat cells (DFAT cells) and adipose-derived stem cells (ASCs). Method: We isolated DFAT cells and ASCs from GFP mice. DFAT cells were established by a new culture method using a mesh culture instead of a ceiling culture. The isolated DFAT cells and ASCs were incubated in osteogenic medium, then alizarin red staining, alkaline phosphatase (ALP) assays, and RT-PCR (for RUNX2, osteopontin, DLX5, osterix, and osteocalcin) were performed to evaluate the osteoblastic differentiation ability of both cell types in vitro. In vivo, the DFAT cells and ASCs were incubated in osteogenic medium for four weeks and seeded on collagen composite scaffolds, then implanted subcutaneously into the backs of mice. We then performed hematoxylin and eosin staining and immunostaining for GFP and osteocalcin. Results: The alizarin red-stained areas in DFAT cells showed weak calcification ability at two weeks, but high calcification ability at three weeks, similar to ASCs. The ALP levels of ASCs increased earlier than in DFAT cells and showed a significant difference (p < 0.05) at 6 and 9 days. The ALP levels of DFATs were higher than those of ASCs after 12 days. The expression levels of osteoblast marker genes (osterix and osteocalcin) of DFAT cells and ASCs were higher after osteogenic differentiation culture. Conclusion: DFAT cells are easily isolated from a small amount of adipose tissue and are readily expanded with high purity; thus, DFAT cells are applicable to many tissue-engineering strategies and cell-based therapies.     

Mechanism of enhanced impact strength of poly(vinyl chloride) modified by acrylic graft copolymer

The mechanism of enhanced PVC impact strength of poly(vinyl chloride) modified by an acrylic graft copolymer was studied by the three-point bending test on a U-notched bar. In the mechanism, the void formation from the modifier released the constrained strain. The release suppresses the stress below the fibril strength in the material; consequently, stable deformation can develop over a large area and, thus, the impact strength of PVC modified by the acrylic graft copolymer is improved. © 1996 John Wiley & Sons, Inc.     

Accelerated weathering-induced degradation of poly(lactic acid) fiber studied by near-infrared (NIR) hyperspectral imaging

Hydrolysis degradation of a set of drawn poly(lactic acid) (PLA) fibers was induced by an accelerated weathering test, radiating ultraviolet (UV) light under a certain temperature and humidity. The fine features of the transient behavior of the PLA fibers were captured by near-infrared (NIR) hyperspectral imaging. The PLA fibers showed a gradual decrease in mechanical property (e.g., tensile strength), indicating hydrolysis degradation. Thus, the detailed analysis of the spectral variation, in turn, offers useful information on the molecular-level degradation behavior of the drawn PLA fibers. The variation of the spectral intensity as well as band position shift of the crystalline band of PLA was analyzed. The spectral intensity of the crystalline band of PLA showed gradual decrease, suggesting the decrease in molecular weight induced by the hydrolysis degradation. In addition, the crystalline band also exhibited a coinciding shift to the lower wavenumber direction with the weathering test, revealing cleavage-induced crystallization of the PLA samples. Consequently, the hydrolysis degradation induced by the weathering test substantially accelerates predominant degradation of the amorphous structure of the PLA and such variation of the molecular structure, in turn, brings less ductility to the PLA fiber.     

Zeta potential of alumina powders with different crystalline phases in simulated body fluids

The zeta potential of alumina (Al₂O₃) powder with different crystalline phases, prepared by heat treatment of boehmite, was measured in simulated body fluids in order to discuss the mechanism on in vivo formation of a calcium and phosphorus (CaP)-rich layer on bone cement containing δ-Al₂O₃-based bead powder. γ, δ, and θ-Al₂O₃ powders were obtained by heat treatment of boehmite powder at 600 °C, 900 °C, and 1025 °C, respectively. It was found that δ-Al₂O₃ gave a negative zeta potential in an acidic simulated body fluid, whereas γ-Al₂O₃ and θ-Al₂O₃ gave a positive potentials. During the bone fracture healing process, acidic conditions are maintained at the site of fracture for several days. Consequently, it is speculated that the negative surface potential of δ-Al₂O₃ in an acidic body fluid, similar to the fracture site, might be responsible for the in vivo formation of the CaP-rich layer on the overlying bone cement, given that the negatively charged surface of δ-Al₂O₃ would attract calcium ions from the surrounding body fluid, thereby facilitating the formation of the CaP-rich layer.