Properties of CC-normal operators (Research on preserver problems on Banach algebras and related topics)

We study various properties of $C$-normal operators, i.e., $T*T$ = $CTT*C$ holds for a conjugation $C$ on $H$. Especially, we show that $T$ − λ$I$ is $C$-normal for all λ ∈ ℂ if and only if $T$ is a complex symmetric operator with the conjugation $C$. In addition, we prove that if $T$ is $C$-normal, then $T$ is normal ⇔ $T$ is quasinormal ⇔ $T$ is hyponormal ⇔ $T$ is $p$-hyponormal for 0 < $p$ ≤ 1. Finally, we investigate equivalent conditions so that Aluthge and Duggal transforms of $C$-normal operators to be $C$-normal operators

Effects of Aging Time and Natural Antioxidants on the Quality of Irradiated Ground Beef

Beef rounds aged for one, two, or three weeks after slaughtering were ground added with 0.05% ascorbic acid + 0.01% α-tocopherol or 0.05% ascorbic acid + 0.01% α- tocopherol + 0.01% sesamol, placed on Styrofoam trays and wrapped with oxygen permeable plastic film, and treated with electron beam irradiation at 0 or 2.5 kGy. The meat samples were displayed under fluorescent light for 7 d at 4° C. Color, lipid oxidation, and volatiles were determined at 0, 3, and 7 d of storage. Irradiation increased lipid oxidation of ground beef regardless of their aging time and storage period. As aging time increased lipid oxidation increased. Adding sesamol increased the effectiveness of ascorbate and tocopherol combination in reducing lipid oxidation especially as aging and storage time increased. The redness of beef were decreased by irradiation and adding ascorbic acid and α-tocopherol before irradiation was effective in maintaining the redness of irradiated ground beef over the storage period. Volatile aldehydes increased only in irradiated control beef. Antioxidant treatments were effective in reducing aldehydes in ground beef during storage

Towards Neural Decoding of Imagined Speech based on Spoken Speech

Decoding imagined speech from human brain signals is a challenging and important issue that may enable human communication via brain signals. While imagined speech can be the paradigm for silent communication via brain signals, it is always hard to collect enough stable data to train the decoding model. Meanwhile, spoken speech data is relatively easy and to obtain, implying the significance of utilizing spoken speech brain signals to decode imagined speech. In this paper, we performed a preliminary analysis to find out whether if it would be possible to utilize spoken speech electroencephalography data to decode imagined speech, by simply applying the pre-trained model trained with spoken speech brain signals to decode imagined speech. While the classification performance of imagined speech data solely used to train and validation was 30.5 %, the transferred performance of spoken speech based classifier to imagined speech data displayed average accuracy of 26.8 % which did not have statistically significant difference compared to the imagined speech based classifier (p = 0.0983, chi-square = 4.64). For more comprehensive analysis, we compared the result with the visual imagery dataset, which would naturally be less related to spoken speech compared to the imagined speech. As a result, visual imagery have shown solely trained performance of 31.8 % and transferred performance of 26.3 % which had shown statistically significant difference between each other (p = 0.022, chi-square = 7.64). Our results imply the potential of applying spoken speech to decode imagined speech, as well as their underlying common features.Comment: 4 pages, 2 figure

Protective Effect of Heme Oxygenase-1 on High Glucose-Induced Pancreatic β-Cell Injury

BackgroundGlucose toxicity that is caused by chronic exposure to a high glucose concentration leads to islet dysfunction and induces apoptosis in pancreatic β-cells. Heme oxygenase-1 (HO-1) has been identified as an anti-apoptotic and cytoprotective gene. The purpose of this study is to investigate whether HO-1 up-regulation when using metalloprotophyrin (cobalt protoporphyrin, CoPP) could protect pancreatic β-cells from high glucose-induced apoptosis.MethodsReverse transcription-polymerase chain reaction was performed to analyze the CoPP-induced mRNA expression of HO-1. Cell viability of INS-1 cells cultured in the presence of CoPP was examined by acridine orange/propidium iodide staining. The generation of intracellular reactive oxygen species (ROS) was measured using flow cytometry. Glucose stimulated insulin secretion (GSIS) was determined following incubation with CoPP in different glucose concentrations.ResultsCoPP increased HO-1 mRNA expression in both a dose- and time-dependent manner. Overexpression of HO-1 inhibited caspase-3, and the number of dead cells in the presence of CoPP was significantly decreased when exposed to high glucose conditions (HG). CoPP also decreased the generation of intracellular ROS by 50% during 72 hours of culture with HG. However, decreased GSIS was not recovered even in the presence of CoPP.ConclusionOur data suggest that CoPP-induced HO-1 up-regulation results in protection from high glucose-induced apoptosis in INS-1 cells; however, glucose stimulated insulin secretion is not restored

Isang Yun's musical bilingualism: serial technique and Korean elements in Fünf Stücke für Klavier (1958) and his later piano works

Isang Yun (1917-1995) was a Korean composer residing in Germany after 1957. Reflecting his musical training in both the East and West, Yun's music integrates serial techniques with elements of Korean traditional music. Yun's piano music merits attention for developing this combination in great depth, as perhaps best exemplified by Fünf Stücke für Klavier (1958). His later piano works, Shao Yang Yin (1966) and Interludium A für Klavier (1982) emphasize aspects of Korean traditional music more strongly. This study intends to assist pianists to develop an informed interpretation of these works based on an understanding of Yun's musical bilingualism

Packaging Determines Color and Odor of Irradiated Ground Beef

Irradiation of ground beef under aerobic conditions oxidized myoglobin and drastically reduced color a*-values. Under vacuum or non-oxygen conditions, however, irradiation did not influence the redness of ground beef. Also, the red color of ground beef was maintained even after the irradiated beef was exposed to aerobic conditions. Vacuum-packaged irradiated ground beef had lower metmyoglobin content and lower oxidation-reduction potential than the aerobically packaged ones. Irradiating ground beef under vacuum-packaging conditions was also advantageous in preventing lipid oxidation and aldehydes production. Vacuum-packaged irradiated beef, however, produced high levels of sulfur volatiles during irradiation and maintained their levels during storage, which resulted in the production of characteristic irradiation off-odor. Double-packaging (V3/A3: vacuum-packaging during irradiation and the first 3 days of storage and then aerobic-packaging for the remaining 3 days) was an effective alternative in maintaining original beef color (red), and minimizing lipid oxidation and irradiation off-odor. The levels of off-odor volatiles in double-packaged irradiated ground beef were comparable to that of aerobically packaged ones, and the degree of lipid oxidation and color changes were close to those of vacuum-packaged ones. Ascorbic acid at 200 ppm level was not effective in preventing color changes and lipid oxidation in irradiated ground beef under aerobic conditions, but was helpful in minimizing quality changes in doublepackaged irradiated ground beef. This suggested that preventing oxygen contact from meat during irradiation and early storage period (V3/A3 double-packaging) and doublepackaging+ascorbic acid combination are excellent strategies to prevent off-odor production and color changes in irradiated ground beef. Developing methods that can prevent quality changes of irradiated beef is important for the implication of irradiation, which will improve the safety of beef

Severe recurrent nocturnal hypoglycemia during chemotherapy with 6-mercaptopurine in a child with acute lymphoblastic leukemia

Various endocrine dysfunctions occur during chemotherapy, including hypoglycemia. However, reports of hypoglycemia associated with 6-mercaptopurine (6-MP) are rare. Herein, we report an 8-year-old boy with severe symptomatic hypoglycemia likely due to 6-MP during chemotherapy. He had been diagnosed with acute lymphoblastic leukemia 3 years previously and was in the maintenance chemotherapy period. Treatment included oral dexamethasone, methotrexate, and 6-MP, of which only 6-MP was administered daily. Hypoglycemic symptoms appeared mainly at dawn, and his serum glucose dropped to a minimum of 37 mg/dL. Laboratory findings showed nothing specific other than increased serum cortisol, free fatty acids, ketone, alanine aminotransferase, and aspartate aminotransferase. Under the hypothesis of hypoglycemia due to chemotherapy drugs, we changed the time of 6-MP from evening to morning and recommended him to ingest carbohydrate-rich foods before bedtime. Hypoglycemia improved dramatically, and there was no further episode during the remaining maintenance chemotherapy period. To the best of our knowledge, this is the first report of this type of hypoglycemia occurring in an Asian child including Korean