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Divinyl ethers were synthesized from 1,3-dicarbonyl compounds. Reactions of β-ketoesters and 1,3-diketones with ethyl propynoate in the presence of N -methylmorpholine produced unusual O -conjugate addition products in good yields. The divinyl ethers derived from 1,3-diketones were utilized for the synthesis of 2,3,5-trisubstituted furans under the standard radical cyclization conditions.

In this paper, the OFB processor, which encrypts real-time data (stream type) on a noisy channel such as satellite communication, is implemented. We design four main blocks, which are Key Interface block, DES block of two-round method, Shift Reg block and Sel discard block necessary for implementation of the OFB processor. These blocks are modeled in VHDL and verified by simulation and synthesis. The proposed OFB processor is designed in full-custom by 0.6 mm Hyun Dai fabrication using the IDEC-C631 library.

In manufacturing microelectronic devices, local pattern distortions such as notching have been frequently observed in gate etch processes when the etching was specifically associated with high density plasmas. Recently, high-k materials have been incorporated as gate dielectrics to meet a requirement for sub-100 nm scale devices. The use of the high-k dielectric materials has replaced the polysilicon-based gate with metal gates to overcome some limitations, such as the gate depletion effect and the gate-line sheet resistance. In this study, we have investigated the etching characteristics of W/TiN gate electrodes coupled with thin high-k dielectric layers, such as Ta/sub 2/O/sub 5/ and Al/sub 2/O/sub 3/. We found that etching profiles of the metal electrodes are predominantly dependent on etching gases as well as the type of underlying dielectric material.

A competitive enzyme-linked immunosorbent assay (ELISA) was developed for the quantitative detection of the organophosphorus insecticide bromophos-ethyl. Four bromophos-ethyl derivatives (haptens) were synthesized and were coupled to carrier proteins through the pesticide thiophosphate group to use as an immunogen or as a coating antigen. Rabbits were immunized with either one of two haptens coupled to bovine serum albumin for production of polyclonal antibodies, and the sera were screened against one of the haptens coupled to ovalbumin. Using the serum with highest titer, an antigen-coated ELISA was developed, which showed an IC 5 0 of 3.9 ng/mL with a detection limit of 0.3 ng/mL (20% inhibition). An antibody-coated ELISA using an enzyme tracer was also developed, which showed an IC 5 0 of 6.5 ng/mL with a detection limit of 1.0 ng/mL (20% inhibition). The antibodies showed negligible cross-reactivity with other organophosphorus pesticides except with the insecticides bromophos-methyl and chlorpyrifos in the antibody-coated assay only. Recoveries of bromophos-ethyl from fortified crop and water samples ranged from 82 to 128% and from 95 to 127%, respectively.

We proposed a simple and cost-effective burst mode bit discrimination circuit for dual rate reach extender based on 10 gigabit Ethernet passive optical network. To distinguish the dual rate burst mode packets, periodic idle patterns which have specific frequency components in the frequency domain and radio frequency power detection technique were used. The burst mode dual rate upstream transmission was demonstrated to confirm the feasibility of our suggested method in a coexisted gigabit Ethernet passive optical network and 10 gigabit Ethernet passive optical network. We achieved the dual rate burst mode receiver sensitivity of - 32 dBm for 1.25 Gbit/s signal and -27 dBm for 10.3 Gbit/s signal, respectively.

This study was conducted to evaluate the antihyperglycemic effects of three phytoestrogens, genistein, coumestrol, and enterolactone, in type 2 diabetic animals. Forty male C57BL/KsOlaHsd-db/db mice were used as a diabetic animal model. The animals were divided into four groups and fed a phytoestrogen-free AIN-76 diet (control), or one of three phytoestrogen-supplemented (3.75 mg/100 g diet) AIN-76 diets for six weeks. During the experimental period, fasting blood glucose levels were measured on week 0, 2, 5, and 6 of the experiment, and oral glucose tolerance tests were performed on the 5th week. After the experimental period, blood concentrations of HbA1c, insulin, and glucagon were measured, and hepatic glycogen content and glucose regulating enzyme activities were analyzed. Fasting blood glucose, HbA1c level, and the area under the blood glucose curve in the oral glucose tolerance test were significantly lower in all of the phytoestrogen-supplemented groups compared to the control group. Plasma glucagon levels were also significantly lower in all of the phytoestrogen-supplemented groups compared to the control group. Hepatic glycogen level was significantly higher in the coumestrol-supplemented group compared to the other groups. However, there were no significant differences in the activities of glucokinase and glucose-6-phosphatase between the groups. These results suggest that all of the three major phytoestrogens tested in the present study were effective in lowering blood glucose levels in type 2 diabetic animals. However, further studies need to be conducted to elucidate the exact mechanism for the hypoglycemic effects of phytoestrogens. (Korean J Nutr 2011 44(4): 275 ~ 283)

The serum levels of antioxidant materials (α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene, α-tocopherol, γ-tocopherol, retinol) of the healthy Korean middle-aged adults (n = 373) were measured and their relationships with the serum lipids and anthropometric indices were analyzed. The serum levels of β-cryptoxanthin, β-carotene, lutein were higher than those of lycopene and α-carotene. The levels of all measured carotenoids except lutein were significantly higher in females than in males, but retinol level was vice versa. There was a tendency of increase in serum levels of antioxidant vitamins with increasing age. The serum carotenoid levels had a positive correlation with serum cholesterol and a negative correlation with serum triglyceride. The serum levels of tocopherols or retinol showed a significantly positive relationship with blood cholesterol or triglyceride. In overall, anthropometric indices showed negative relations with serum carotenoids levels, but vice versa with serum tocopherol or retinol levels. Particularly, β-carotene and lutein levels showed a significantly negative relation with blood pressure in male subjects. The serum levels of α-carotene, β-carotene and β-cryptoxanthin had significantly negative relations with body fat-related indices in female subjects. The results demonstrated that blood antioxidants levels differed by sex and age, and had significant relations with blood lipid levels and anthropometric indices. Therefore, the rationale and significance of the relationships need to be elucidated in the future study related to dietary intakes and life style. (Korean J Nutr 2009; 42(5): 464 ~ 473)

Equivalent concentrations of polydextrose and sucrose had similar effects on phase transitions of wheat starch-water systems. Onset and peak gelatinization temperatures were increased similarly with the two solutes. This was true with varied water:starch ratios, varied concentrations of solute, and for batters prepared with the two solutes. Acesulfame K, cyclamate, and saccharin at low levels, as might be used in food products, had little effect on phase transitions of starch-water-solute systems.