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71.
The influences of soaking treatment and storage conditions on the softening of cooked beans, namely, soybeans and red kidney beans, were investigated. It was revealed that the softening of fresh soybeans and fresh red kidney beans was suppressed during subsequent boiling after soaking treatment at 50 and 60 °C. Furthermore, in treated aged soybeans and red kidney beans that were subjected to storage at 30 °C/75% relative humidity for 6 mo and soaking treatment at 50 to 60 °C, the hardness during cooking was further amplified. This suggested that the mechanism of softening suppression differs depending on the influences of soaking and storage. Analysis of the pectin fraction in alcohol insoluble solid showed insolubilization of metal ions upon storage at high temperature and high humidity in both soybeans and red kidney beans, which suggests interaction between Ca ions and hemicellulose or cellulose as cell wall polysaccharides. The results of differential scanning calorimetry (DSC) showed that aged soybeans exhibited a shift in the thermal transition temperature of glycinin‐based protein to a higher temperature compared with fresh soybeans. From the results of DSC and scanning electron microscopy for aged red kidney beans, damaged starch is not conspicuous in the raw state after storage but is abundant upon soaking treatment. As for the influence of soaking at 60 °C, it can be suggested that its influence on cell wall crosslinking was large in soybeans and red kidney beans in both a fresh state and an aged state.  相似文献   
72.
73.
The extractive components of raw and boiled–dried scallop adductor muscle were examined. On a dry weight basis the levels of total free amino acids, total adenosine triphosphate (ATP) and related compounds, and betaines in the boiled–dried sample were lower than those in the raw muscle, which may have been due to the outflow of these compounds during boiling. Soup prepared from the boiled–dried scallop and chicken leg meat was assessed by sensory evaluation. This soup cooked with the scallop and chicken was stronger in sweetness, umami and body and rated higher in overall preference than the soup containing these ingredients after cooking separately. The inosine monophosphate (IMP) level in the former soup was 4.4 times higher than that in the latter. The adenosine monophosphate (AMP) deaminase (EC 3.5.4.6) activity in the crude extract from the chicken meat was 9.16 units l?1, whereas no activity could be detected in the crude extract from the boiled–dried scallop. It is concluded that AMP, which was mainly derived from the boiled–dried scallop, was converted to IMP by AMP deaminase from the chicken meat during the preparation of the soup, resulting in an improvement in the taste. Copyright © 2004 Society of Chemical Industry  相似文献   
74.
Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) were determined in the liver and pectoral muscle of common cormorants (Phalacrocorax carbo) collected from Lake Biwa, Japan. To clarify the toxicokinetic behaviors and potential toxicities of these chemicals, the present study addresses life-stage- and tissue-specific accumulation of the congeners. Total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) were in the range of 360 to 50,000 pg/g lipid weight in the liver and 310 to 12,000 pg/g lipid weight in the pectoral muscle. Among congeners, for which toxic equivalency factors were assigned, PCB126, 2,3,4,7,8-P5CDF, and 1,2,3,7,8-P5CDD made a greater contribution to total TEQs in the liver. Hepatic concentrations of T4- to H6CDDs, P5- and H6CDFs, and Co-PCBs (except PCB77) significantly increased with growth of cormorants, leading to life-stage-related compositional changes. The concentration ratios of liver to pectoral muscle revealed preferential accumulation of higher chlorinated congeners in hepatic tissue. For most congeners, concentration ratios significantly increased with an increase in hepatic total TEQs, suggesting their concentration-dependent hepatic sequestration. These results imply the presence of hepatic binding protein(s) such as cytochrome P450, inducible by these chemicals, which mayfunction as a binding species different from aryl hydrocarbon receptor. On the basis of these results, we conclude that the toxicokinetic behavior of each congener is life-stage-, tissue-, and concentration-dependent. TEQs in wildlife populations exposed to multiple congeners with varying concentrations should be used with caution for risk assessment, even within a species.  相似文献   
75.
Assessment of groundwater pollution in Tokyo using PPCPs as sewage markers   总被引:1,自引:0,他引:1  
While the occurrence of pharmaceuticals and personal care products (PPCPs) in groundwater has typically been reported in bank filtration sites, irrigated fields, septic tanks, and sewage disposal practices, fewer studies have been conducted in highly urbanized areas, where infiltration of treated or untreated sewage is not supposed to be a source of groundwater recharge. Furthermore, little is known about the occurrence of various kinds of PPCPs in relation to microbial indicators in groundwater from different types of aquifers. Thus, we examined the city-wide occurrence of selected PPCPs (diethyltoluamide, crotamiton, ethenzamide, propyphenazone, carbamazepine, and caffeine) and E. coli in 50 groundwaters from unconfined aquifers (<30 m in depth) and confined aquifers (up to 500 m in depth) in Tokyo, where unintended groundwater contamination could take place due to decrepit sewer networks. PPCPs were detected in unconfined aquifers and springs (23/34 samples, 68%), and in confined aquifers (7/16 samples, 44%). Compared with published results for sewage influents, concentrations of PPCPs, excluding caffeine, were generally 1-2 orders of magnitude lower, while in some samples concentrations were quite comparable. The high occurrence rate of PPCPs, even in confined aquifers, indicated that such aquifers are not always protected from pollution by sewage near the land surface. Among the PPCPs analyzed, carbamazepine and crotamiton were most frequently detected, which would appear to be owing to their high persistence, combined with the high concentration of crotamiton in sewage. Crotamiton was detected in all four E. coli-positive groundwaters, and thus may potentially serve as a precautionary indicator of E. coli contamination. Using carbamazepine as a sewage marker, we estimated that 0.8%-1.7% of the dry-weather flow of sewage was leaking out into the unconfined aquifers.  相似文献   
76.
Two clones with homology to known fatty acid desaturase genes were isolated from the yeast Kluyveromyces lactis. The first gene, which we designate KlFAD2, consists of 411 amino acids with an overall identity of 73.0% to FAD2 from Saccharomyces kluyveri. It exhibited Delta12 fatty acid desaturase activity when expressed in S. cerevisiae under the control of ADH1 promoter and produced endogenous linoleic acid. The second clone, which we designate KlFAD3, consists of 415 amino acids with an overall identity of 79.3% to FAD3 from S. kluyveri. It exhibited omega3 fatty acid desaturase activity in S. cerevisiae when expressed under the control of ADH1 promoter in the presence of the exogenous substrate linoleic acid and produced alpha-linolenic acid. Co-expression of KlFAD2 and KlFAD3 resulted in the endogenous production of both linoleic and alpha-linolenic acids. The yield of alpha-linolenic acid reached 0.8% of total fatty acids and its production was not increased by adding exogenous oleic acid; alpha-linolenic acid reached 8.7% when exogenous linoleic acid was available.  相似文献   
77.
To evaluate dioxin contamination in retail vegetables, congener analyses of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (Co-PCBs) were performed on sixty varieties of fresh vegetables including cereals and mushrooms, obtained from Japanese supermarkets in 2002. The toxic equivalent quantity (TEQ) levels for dioxins in samples ranged from < 0.001 to 0.089 pg-TEQ/g wet weight, when undetected and trace were taken as zero. Among the samples, dioxins were generally detected in green leafy vegetables. The highest TEQ value was for mulukhiya (0.089 pg-TEQ/g), followed by spinach and komatsuna (Japanese mustard spinach) (0.077 and 0.074 pg-TEQ/g, respectively). Additionally, the dioxin levels in seventeen varieties of frozen vegetables were also determined, and showed TEQ values ranging from < 0.001 to 0.080 pg-TEQ/g. The total TEQ in commercial vegetables mainly reflected the levels of 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF and 3,3',4,4',5-PeCB (#126) (the sum of them represented 63% of the total TEQ).  相似文献   
78.
This article argues how one problem of computing lies in realizing a significant instance given a class or type. Analysis of a case study on digital narrative suggests two general processes for instantiating significant instances: interaction and optimization. The article then explains how the problem of universals needs to be deconstructed when trying to understand what type of entities significant instances are and what the process for obtaining them is.
Kumiko Tanaka-IshiiEmail:
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79.
We constructed a wearable and flexible humidity sensor (thickness: 80 μm) in a sandwich configuration, with a hydrophilic poly-tetrafluoroethylene membrane placed between two gold deposited layers, using soft-MEMS techniques. The device was used to measure humidity level, via its electrical conductivity, using a multi-frequency LCR-meter at frequencies ranging from 100 Hz to 100 kHz. The device was calibrated at 100 Hz against moist air over the range of 30–85% RH, which includes normal humidity levels in the atmosphere and physiological air such as breath and evaporating sweat. The response sensitivity of the humidity device was extremely high, even for recovery to dry air; for example response time was less than 1 s for a conductivity shift between humid air of 80% RH and dry air of −60 °C dew point. The sensor performance was reproducible over multiple measurements, with a coefficient of variation of 1.77% (n = 5). The sensor was appropriate for physiological applications, and was successfully used in two non-invasive approaches: to monitor breath air at the mouth, and to measure sweat moisture from the nostrils.  相似文献   
80.
Recurrent miscarriage is a heterogeneous condition which has many possible underlying causes. Ideally, couples with the problem should be managed in a dedicated miscarriage clinic, with thorough investigations according to a protocol, with structured history and investigation sheets. Counselling is an important feature and may be provided by a specially trained counsellor, or specialized nurse appropriately trained in counselling. Counselling should include an explanation of the possible underlying causes of the condition, and of the prognosis of each of the conditions. There is no definite cause of miscarriage in approximately half of the patients. No treatment is needed in this group, apart from reassurance and tender loving care. Treatment of unproven value, for example progesterone support in early pregnancy, should not be offered. Treatment offered empirically or as part of a research project should have a sound scientific and statistical basis, and should include careful counselling with informed consent of the patient. There are many controversial issues in the management of recurrent miscarriage; consequently, there is a need for locally agreed guidelines for management. Women who conceive again should be offered regular monitoring, including serial ultrasonography in the first trimester of pregnancy. An active audit programme to review regularly the various outcome measures set against defined targets should be established in the clinic.  相似文献   
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