Development of discontinuous grinding wheel with multi-porous grooves

Conventionally, grinding of aluminium, copper and stainless steel is difficult owing to the mechanical properties such as low hardness and high toughness which result in the wheel loading and poor surface finish. In order to grind these materials easily, a discontinuous grinding wheel with multi-porous grooves has been recently developed. The multi-porous grooves were formed during wheel manufacturing. The discontinuous grinding wheel dramatically increases the grinding performance. It is desirable to use discontinuous grinding wheel when grinding materials with high efficiency and accuracy which is impossible using conventional wheels.In this paper, the construction and manufacturing method of discontinuous grinding wheel with multi-porous grooves are explained. The grinding characteristics of the discontinuous grinding wheel is also illustrated.     

Bioinformatics and its role in the study of the evolution and probiotic potential of lactic acid bacteria

Food Science and Biotechnology - Due to their numerous well-established applications in the food industry, there have been many studies regarding the adaptation and evolution of lactic acid...     

Molecular typing tools for identifying and characterizing lactic acid bacteria: a review

Food Science and Biotechnology - Identification and classification of beneficial microbes is of the highest significance in food science and related industries. Conventional phenotypic approaches...     

Analysis of Leuconostoc citreum strains using multilocus sequence typing

Food Science and Biotechnology - The objective of this study was to perform genetic diversity analysis of 13 strains isolated from South Korean foods by multilocus sequence typing (MLST). For...     

High efficiency and non-color-changing orange organic light emitting diodes with red and green emitting layers

We report a high performance orange organic light-emitting diode (OLED) where red and green phosphorescent dyes are doped in an exciplex forming co-host as separate red and green emitting layers (EMLs). The OLED shows a maximum external quantum efficiency (EQE) of 22.8%, a low roll-off of efficiency with an EQE of 19.6% at 10,000 cd/m², and good orange color with a CIE coordinate of (0.442, 0.529) and no color change from 1000 to 10,000 cd/m². The exciplex forming co-host system distributes the recombination zone all over the EMLs and reduces the triplet exciton quenching processes.     

A host material containing tetraphenylsilane for phosphorescent OLEDs with high efficiency and operational stability

A host material containing tetraphenylsilane moiety, 9-(4-triphenylsilanyl-(1,1′,4,1′′)-terphenyl-4′′-yl)-9H-carbazole (TSTC), was synthesized for green phosphorescent organic light emitting diodes. The tetraphenylsilane moiety was introduced to provide high triplet energy level, thermal and chemical stability, and glassy properties leading to high efficiency and operational stability of the devices. Ir(ppy)₃ based OLEDs using the TSTC host and DTBT (2,4-diphenyl-6-(4′-triphenylsilanyl-biphenyl-4-yl)-1,3,5-triazine) hole blocking layer (HBL) resulted in the maximum external quantum efficiency of 19.8% and the power efficiency of 59.4 lm/W. High operational stability with a half lifetime of 160,000 h at an initial luminance of 100 cd/m² was achieved from an electrophosphorescent device using TSTC host and BAlq HBL.     

Populations and potential association of Saccharomyces cerevisiae with lactic acid bacteria in naturally fermented Korean rice wine

The microbial populations focused on predominant yeast species and lactic acid bacteria (LAB) in 15 commercial makgeolli brands, where a fungal starter nuruk was used were examined. Viable yeast counts were obtained on yeast potato dextrose (YPD) and MRS agar containing sodium azide. MRS-C (0.1% cycloheximide supplemented) was used for selective counts of LAB. Saccharomyces cerevisiae was found to be predominant in the 15 samples tested, with an average count of 4.6×10⁷ CFU/mL. Contrary to the earlier studies, Lactobacillus plantarum and Weissella cibaria were shown as predominant LAB species with an average count of 1.7×10⁷ CFU/mL. Surprisingly, as many as 7 log viable cells/mL were present at the ethyl alcohol concentration of 6–7%. The data from real-time PCR also indicated that the yeast populations remains almost constant during the refrigerated storage of 12 days, while that of LAB decrease slightly first 9 days and increase after then, despite the overall increase in acidity. Data from the differential microbial counts suggest that yeast S. cerevisiae might be associated with 2 LAB species, L. plantarum and W. cibaria, under ethyl alcohol stress during the turbid rice wine fermentation.     

In vitro cytoprotective effect of infant milk formula fortified with human rotavirus-specific hyperimmune yolk immunoglobulins (IgY)

Infant formula supplemented with hyperimmune immunoglobulin Y (IgY) against human rotavirus (HRV) was evaluated in vitro against HRV reassortant clinical strains ATCC VR 2273 and ATCC VR 2274. Specific antihuman rotavirus antibody powder (Rotamix IgY) was prepared. The effectiveness of Rotamix IgY alone and as a pre-mixed solution with infant formula was evaluated for neutralizing rotavirus infectivity in MA104 cells. The test infant formula cross-reacted strongly against different human rotavirus strains with titers of 80-320 using a 50% fluorescent focus (FF) inhibition test. Both rotamix IgY alone and in a pre-mixed solution with infant formula showed multi-serotypic cross neutralization activities against the major rotavirus global serotypes G1, G2, G3, and G4 alone and with other human and animal-strains in vitro. Cell-rotavirus adhesion and cell damage arising from rotavirus infection were significantly inhibited in a dose dependent manner, compared to control IgY supplemented infant formula.     

The effect of kimchi on the microbiological stability of fermented sausage

The effects of kimchi and freeze-dried kimchi-powder added to raw meat mixtures on the microbiological quality of fermented sausage were studied. The results clearly demonstrated that the lactic acid bacteria (LAB) integrated via the addition of kimchi as well as kimchi-powder were well adapted to the new habitat of fermenting sausage, reaching maximum numbers of 8.65-8.80log(10)cfu/g after 1-2days of fermentation. In all kimchi and kimchi-powder sausages, the growth of Enterobacteriaceae was completely inhibited throughout the processing period (<2log(10)cfu/g). The sausage batches containing more than 10% kimchi and 2% kimchi-powder showed no growth of S. aureus, whereas the control and another kimchi sausage batch reflected the growth of S. aureus (3.68-4.72log(10)cfu/g). As a result, the addition of kimchi (≥10%) and kimchi-powder to the sausage mixture prior to fermentation produced the microbiological stability required for fermented sausages.     

RAPD typing of <Emphasis Type="Italic">Lactobacillus brevis</Emphasis> isolated from various food products from Korea

In the present study, the fingerprinting technique, random amplified polymorphic DNA-PCR was evaluated to characterize 13 strains of Lactobacillus brevis, isolated from different vegetable products of South Korea. Two primers i.e. 239 and KAY3 were used. The primer 239 produced bands ranged from 500-4,000 bp and KAY3 primer produced bands with sizes from 600-4,000 bp. Both primers produced thirteen different RAPD profiles. Phylogenetic dendrogram showed that all the isolates could be divided into six major clusters both the primers. However, a few strains of L. brevis had similar profiles and were not well differentiated by RAPD.