Improvement of Dynamic Stability in a Multimachine Power System via SMES with Active Power Modulation Controlled by Frequency Deviation

With the recent increase in demand, power systems have become large and complex and generation plants are located far from the load center. As a result, power system instability has become more serious. On the other hand, the active and reactive powers am controlled rapidly and flexibly by the superconducting magnetic energy storage (SMES) system. This paper proposes a practical method to suppress power oscillation in a multimachine power system by using SMES wherein its active power is controlled by the signal derived from a bus frequency deviation. This controlled scheme is conducted easily only by detecting the frequency deviation on the site. The proposed method is examined on a 4-machine miniature power system connecting a I-MJ SMES as well as another digital simulation using the same model. The effectiveness of the proposed method is shown.     

Gonadotropins, serum, and amino acids alter nuclear maturation, cumulus expansion, and oocyte morphology in hamster cumulus-oocyte complexes in vitro

Glucose, lactate, and pyruvate (the substrate triad), gonadotropins, serum, and amino acids were tested on maturation of cumulus-oocyte complexes (COCs) using a simple defined medium, Tyrode's-PVA (T-PVA). In experiment 1, effects of FSH (2 microg/ml) and the substrate triad were tested using a 2 x 2 factorial design. After 12-13 h, nuclear maturation was depressed in the absence of the triad or with FSH (0-14% metaphase II [MII]) compared with the triad alone (92% MII, p < 0.05). Subsequent experiments used as the base medium Tyrode's solution with the triad (TLP-PVA): adding 10% bovine calf serum (BCS) and gonadotropins (10 microg/ml FSH, 10 microg/ml LH, or both) yielded nuclear maturation equivalent to that in medium alone (88-100% post-metaphase I [post-MI] oocytes). Responses with glutamine, or with 11 but not 20 amino acids, were equivalent to the response in BCS with gonadotropins (93-100% post-MI oocytes). Some cumulus expansion occurred in COCs matured with gonadotropins and BCS, or glutamine, or 11 amino acids, but was less extensive than for in vivo-matured COCs. Oocytes matured with gonadotropins and BCS, or glutamine, or 11 amino acids plus gonadotropins, but not medium alone, had normal-appearing first polar bodies. Another cytoplasmic marker, cortical distribution of microfilaments (detected by confocal microscopy), did not differ between in vitro- and in vivo-matured oocytes. We conclude that effects of gonadotropins on hamster nuclear maturation, cumulus expansion, and oocyte morphology are modulated by serum or amino acids; maturation conditions producing normal oocyte and cumulus morphologies are predicted to yield developmentally competent oocytes.     

Quantitative analysis of polyenoic phospholipid molecular species by high performance liquid chromatography

The quantitative analysis of phospholipid molecular species containing polyenoic fatty acids is described. Dinitrobenzoyl derivatives of diacylglycerols prepared from phospholipids were separated into individual molecular species by reversed-phase high performance liquid chromatography (HPLC) using a combination of two solvent systems and were quantified at 254 nm. Thirty-six molecular species were resolved from the phosphatidylcholines of rat hearts, human platelets and Chinese hamster V79-R cells. The derivatives of alkenylacyl molecular species from platelet phosphatidylethanolamine were resolved concomitantly with diacyl molecular species.     

Improvement of nutritional value and functional properties of soybean glycinin by protein engineering

Glycinin is one of the predominant storage proteins of soybean.To improve its functional properties (heat-induced gelationand emulsification) and/or nutritional value, the A_1aB_1b proglycininsubunit was modified on the basis of genetically variable domainssuggested from the comparison of amino acid sequences of glycinin-typeglobulins from various legumes and nonlegumes and the relationshipsbetween the structure and the functional properties of glycinin.Thus, nucleotide sequences corresponding to each of the variabledomains were deleted from the cDN A encoding the A_1aB_1b proglycinin,and a synthetic DNA encoding four continuous methionines wasinserted into the cDNA region corresponding to each of the variabledomains. Expression plasmids carrying the modified cDNAs wereconstructed and expressed in Escherichia coli strain JM105.Some of the modified proteins were accumulated as soluble proteinsin the cells at a high level and self-assembled. They exhibitedfunctional properties superior to those of the native glycininfrom soybean, which establishes the possibility of creatingtheoretically designed novel glycinins with high food qualities.     

Phospholipid- phospholipid interaction in soybean oil

Phospholipid-phospholipid interaction in soybean oil is described. Phosphatidylcholine was effectively removed from soybean oil by degumming (water hydration), whereas phosphatidylethanolamine and phosphatidic acid were hardly hydratable. However, the degree of their hydration increased in the presence of phosphatidylcholine. The spectrophotometric assay based on charge transfer interaction between 7,7,8,8-tetracyanoquinodimethane and phospholipids at 480 nm was used to determine the formation of phospholipid micelles in soybean oil. The critical micelle concentrations were 0.085, 0.84 and 2.6 mM for phosphatidylcholine, phosphatidylethanolamine and phosphatidic acid, respectively. Phosphatidylcholine interacted with phosphatidylethanolamine or phosphatidic acid to form mixed micelles. The critical micelle concentrations of phosphatidylcholine-phosphatidylethanolamine mixture and phosphatidylcholine-phosphatidic acid mixture were 0.16 and 1.3 mM, respectively. The degree of hydration of phospholipids was related to their critical micelle concentrations. Interaction of phosphatidylcholine with phosphatidylethanolamine or phosphatidic acid was confirmed by determining the changes in the chemical shifts of 31PNMR spectra.     

Embedded trench DRAMs for sub-0.10-μm generation by usinghemispherical-grain technique and LOCOS collar process

For the future system on chip era, the embedded DRAM is one of the most important devices. Since the kinds of device increase and each device must be produced from only 10000 wafers, it is difficult to withdraw the investment cost to fabricate each device. To suppress the investment cost, the devices must be shrunk by changing the integration and the materials as little as possible. In this paper, we propose the trench capacitor scaling strategy. We show that the strategy achieves 30 fF/cell for the 0.08 μm trench and reduces the cost of ownership (COO) and raw process time (RPT) of the 0.08 μm trench to 80% of 0.18-μm trench, with an investment of only $1.6 M. It is achieved by the LOCOS collar process and HSG technique     

Probing the Superconducting Gap from Tunneling Conductance on NdFeAsO<Subscript>0.7</Subscript> with <Emphasis Type="Italic">T</Emphasis><Subscript>C</Subscript>=51 K

We report the tunneling spectroscopy of an iron-based oxypnictide NdFeAsO_0.7 with T _C=51 K, measured by a mechanical point contact technique. Mainly two kinds of tunneling spectra have been observed reproducibly. One is tunneling conductance displaying sharp superconducting gap peaks at 6.0±1.0 mV, in which hump (or kink) structures are also observed at 20–30 mV. Another is that showing dominantly the larger superconducting gap Δ _L with sharp conductance peaks at 14±1.0 meV, in which the trace of a smaller gap (Δ _S=5–7 meV) is simultaneously observed. Our results give direct evidence for the existence of multiple gaps in the quasiparticle excitation spectrum of this multiband system, although the origin of the hump at 20–30 mV is still unclear.     

Identification of anti-α-enolase autoantibody as a novel serum marker for endometriosis

Diagnosis of endometriosis needs invasive maneuvers. New serum marker that possesses both high sensitivity and high specificity has long been desired. To establish novel serum marker for endometriosis, serum autoantibodies (autoAbs) were investigated using proteomic approach. AutoAbs in sera of endometriotic patients and healthy controls were analyzed using a mesothelial cell line, 2-DE and Western blotting. Proteins in reacted spots were identified using MALDI TOF-MS with MASCOT analysis. ELISAs were established using recombinant proteins and autoAb-titers were estimated in sera of endometriotic patients, disease and healthy controls. Several autoAbs were identified. Anti-α-enolase (Eno1)-autoAb levels in endometriotic patients were significantly elevated compared with both healthy and disease controls. Sensitivity and specificity of serum anti-Eno1-autoAb was nearly comparable to serum CA125. When anti-Eno1-autoAb and CA125 assays were combined, diagnostic sensitivity and accuracy improved. Serum anti-Eno1-autoAb can be a new serum endometriotic marker and it is useful as a supplement assay for CA125. This study validates further clinical evaluation of this novel marker.     

Application of cryopreserved allograft to aortic root replacement for valve detachment case due to aortitis

A 54-year-old male who had received an aortic valve replacement with SJM 23 about 3 years before suffered from an acute cardiac failure because of the valve detachment. From his clinical course, it was diagnosed that the aortic valve insufficiency was complicated by an aortitis. We operated on him by an aortic root replacement using a cryopreserved allograft which we prepared. A donor of the allograft was 35-year-old male, died of a subarachnoidal hemorrhage. We harvested his aortic root at an autopsy and dipped it into a nutrition medium with 10% dimethylsulfoxide. Within 10 hours from his death, we froze the tissue using a program freezer and stored it in a liquid nitrogen for 7 months. After thawing it in 37 degrees C water quickly, we rinsed the graft and used for the operation. The cell viability of the graft was confirmed by a tissue culture. Indication of the allograft valve to an aortitis case is still controversial. We think the allograft is recommendable to valve detachment case due to aortitis, because the softness of the graft decreases a compliance mismatch between the graft and the patient's annulus, which may prevent redetachment. Although we felt concern about redetachment of the conduit due to the weakness of the patient's aortic annulus, no complication regarding the allograft happened at all as yet.