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排序方式: 共有452条查询结果,搜索用时 11 毫秒
91.
Tamami Ida Naoko Crofts Satoko Miura Ryo Matsushima Naoko Fujita 《Journal of Applied Glycoscience》2022,69(2):23
Amylopectin, which consists of highly branched glucose polymers, is a major component of starch. Biochemical processes that regulate the elongation of glucose polymers and the generation and removal of glucose branches are essential for determining the properties of starch. Starch synthases (SSs) and branching enzyme (BE) mainly form complexes consisting of SSI, SSIIa, and BEIIb during endosperm development. Loss of BEIIb in rice is complemented by BEIIa, but the compensatory effects differ depending on the presence or absence of inactive BEIIb. To better understand these compensatory mechanisms, ss2a be2b (+) double mutant, which possessed truncated inactive SSIIa and inactive BEIIb, were analyzed. Soluble proteins separated by gel filtration chromatography showed that SSIIa and BEIIb proteins in the wild-type exhibited a broad range of elution patterns and only small amounts were detected in high molecular mass fractions. In contrast, most of truncated inactive SSIIa and inactive BEIIb from ss2a be2b (+) were found in high molecular mass fractions, and the SSI-SSIIa-BEIIb trimeric protein complex found in the wild-type was likely absent in ss2a be2b (+). Those SSIIa and BEIIb proteins in high molecular mass fractions in ss2a be2b (+) were also identified by mass spectrometry. Parental ss2a single mutant had negligible amounts of SSIIa suggesting that the truncated inactive SSIIa was recruited to high-molecular mass complexes in the presence of inactive BEIIb in ss2a be2b (+) double mutant. In addition, SSIVb might be involved in the formation of alternative protein complexes with < 300 kDa in ss2a be2b (+). 相似文献
92.
93.
This study investigates the effects of large-scale research funding from the Japanese government on the research outcomes of university researchers. To evaluate the effects, we use the difference-in-differences estimator and measure research outcomes in terms of number of papers and citation counts per paper. Our analysis shows that the funding program led to an increase in the number of papers in some fields and an increase in the citation counts in the other fields. A comparison of our estimation results with assessment data obtained from peer reviews showed important differences. Since the characteristics of research vary according to the field, bibliometrics analysis should be used along with the peer review method for a more accurate analysis of research impact. 相似文献
94.
It has been recently argued that human bodies are processed by a specialized processing mechanism. Central evidence was that body inversion reduces recognition abilities (body inversion effect; BIE) as much as it does for faces, but more than for other objects. Here we showed that the BIE is markedly reduced for headless bodies and examined the reason for this unexpected finding. Two alternative hypotheses were examined. Either the BIE is reduced for any type of incomplete body, or the head plays a special role in discrimination of body posture. Results show that omission of other body parts (leg or arms) did not influence the magnitude of the BIE relative to complete bodies. Analogous manipulations with faces did not influence the magnitude of the face inversion effect. Importantly, similar to effects we found for headless bodies, discrimination abilities for upright bodies and the BIE were markedly reduced for complete bodies that did not differ in head posture. We conclude that intact discrimination of body posture relies heavily on the head position. Our findings also imply that the BIE and the face inversion effect may be generated by different mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Adenosine triphosphate bioluminescence for hygiene testing of rubber liners and tubes on dairy farms
Ida Clemensson Lindell Åse Lundh Kerstin Svennersten Sjaunja Marika Cederholm 《Journal of dairy science》2018,101(3):2438-2447
Prevention of biofilm formation in milking equipment is important to ensure good hygiene quality of raw milk. Key factors to achieving good results are a successful cleaning procedure and a method to check the cleanliness of milking equipment surfaces. Adenosine triphosphate bioluminescence is a fast and easy method for investigating bacterial contamination of surfaces. However, previous studies on the potential of ATP bioluminescence to assess the hygiene status of milking equipment have been hampered by lack of a validated test procedure. The aim of this work was therefore to establish a test procedure for assessing the cleanliness of milking equipment using ATP bioluminescence, and apply the method on-farm to study the hygiene status of aging rubber material in milking equipment. In developing the test procedure, the effects of sampling location in tubes and liners, sampling of dry versus wet barrels, milking point in the parlor, and acid or alkali detergent on ATP values were investigated. The results showed that, to obtain reproducible results, replicate sampling from the same milking points in the parlor is important. For milk tubes, samples should preferably be taken from the milk meter side, for liners on the inside of the barrel. For best results, sampling should be performed after use of alkali detergent. No beneficial effect was observed of sampling dry liner barrels, so sampling in the standardized test procedure is performed directly after cleaning. The standardized test procedure was used on 3 different commercial farms and sampling was initiated after replacement of old rubber parts. On one of the farms, additional sampling was performed to evaluate total bacteria count and determine the association with ATP level. The results suggest that, provided an efficient cleaning procedure is used, the hygiene quality of milking equipment can be maintained during the recommended lifetime of the rubberware. However, due to occasional variation in cleaning efficiency between milking points and liner barrels, random sampling on single occasions can lead to incorrect conclusions. Replicate sampling over time is therefore important for correct interpretation of ATP bioluminescence data. If ATP levels are very high, complementary sampling for total bacteria count should be used to verify that the level is due to bacterial contamination, and not other organic ATP-contributing material (e.g., milk residues). 相似文献
96.
Pauline R. Kriese Adriana L. Soares Paulo D. Guarnieri Sandra H. Prudencio Elza I. Ida Massami Shimokomaki 《Food chemistry》2007,104(4):1618-1621
Meat tenderness is the main characteristic demanded by consumers and is affected by rigor mortis development and proteolysis activities, both of which occur during carcass refrigeration. In this work, we demonstrate that broiler breast fillet tenderness can be further increased and its extension depends on whether or not meat is excised from the carcass. Post-harvest samples taken from 0 to 72 h after slaughtering and kept refrigerated at 2 ± 2 °C were evaluated for tenderness by myofibrillar fragmentation index determination, shear force analysis and sensorial testing. The 24 h post-harvested intact samples were 30.6% more tender than excised samples and 41.7% more tender than control samples (p ? 0.05). The myofibrillar fragments index was 13.2% higher in intact samples than in deboned fillet (p ? 0.05) and a sensory test showed that the 24 h intact samples were of major acceptability. Our results demonstrated that tenderness was best achieved with intact breast fillet samples stored at 2 ± 2 °C for 24 h. 相似文献
97.
Nataša Čuk Matjaž Kunaver Ida Poljanšek Aleš Ugovšek Milan Šernek Sergej Medved 《Journal of Adhesion Science and Technology》2013,27(15):1553-1562
In this study, we modified melamine-formaldehyde (MF) resin adhesive with liquefied wood (LW) and determined the properties of MF–LW adhesive mixtures. Furthermore, we produced particleboards using prepared MF–LW mixtures and evaluated their mechanical and physical properties. Results showed that with increasing content of LW in the adhesive mixture gel time and peak temperature increased while reaction enthalpy decreased. With increasing substitution of MF resin adhesive with LW the thermal stability of adhesive mixture reduced, namely thermal degradation started at lower temperature and weight loss increased. Properties of particleboards improved with increasing amount of LW in the adhesive mixture up to 20% and then deteriorated. Nevertheless, the properties of particleboard with 30% LW in the adhesive mixture were comparable to the properties of particleboard without LW while they worsen at greater portion of LW. Consequently, MF resin adhesive with 30% LW substitution could be used to produce particleboards with suitable mechanical properties and reduced formaldehyde release content. 相似文献
98.
Monolithic Integration of InP HBTs and Uni-Traveling-Carrier Photodiodes Using Nonselective Regrowth
Kashio N. Kurishima K. Sano K. Ida M. Watanabe N. Fukuyama H. 《Electron Devices, IEEE Transactions on》2007,54(7):1651-1657
This paper describes the monolithic integration of InP HBTs and uni-traveling-carrier photodiodes (UTC-PDs) by nonselective regrowth. HBTs are fabricated from nonselectively regrown device layers and UTC-PD subcollector layers, which are grown first on a 3-in InP substrate. This makes it possible to optimize the layer design for the HBTs and UTC-PDs independently and minimize the interconnection between them. The fabricated HBTs have a collector thickness of 200 nm, and they show an ft of 260 GHz and an fmax of 320 GHz at a collector current density of 2.5 mA/mum2. The standard deviations of the ft and fmax across the wafer are 1.7% and 4.4%, respectively. The length of the interconnection between the HBTs and UTC-PDs can be made as small as 10 mum without any degradation of the regrown-HBT performance. The UTC-PDs fabricated on the same wafer exhibit a 3-dB bandwidth of 100 GHz and an output voltage of 1.0 V. There is no drawback in the performance of either device, as compared with that of discrete devices. We also demonstrate 100-GHz optical-input divide-by-two optoelectronic integrated circuits (OEICs) consisting of InP HBTs and a UTC-PD using this technique. These results indicate that the nonselective regrowth is promising for application toward over 100-Gb/s OEICs. 相似文献
99.
Catharina M. Lerche Ida M. Heerfordt Jakob Heydenreich Hans Christian Wulf 《International journal of molecular sciences》2016,17(3)
Daylight-mediated photodynamic therapy (daylight PDT) is a simple and pain free treatment of actinic keratoses. Weather conditions may not always allow daylight PDT outdoors. We compared the spectrum of five different lamp candidates for indoor “daylight PDT” and investigated their ability to photobleach protoporphyrin IX (PpIX). Furthermore, we measured the amount of PpIX activating daylight available in a glass greenhouse, which can be an alternative when it is uncomfortable for patients to be outdoors. The lamps investigated were: halogen lamps (overhead and slide projector), white light-emitting diode (LED) lamp, red LED panel and lamps used for conventional PDT. Four of the five light sources were able to photobleach PpIX completely. For halogen light and the red LED lamp, 5000 lux could photobleach PpIX whereas 12,000 lux were needed for the white LED lamp. Furthermore, the greenhouse was suitable for daylight PDT since the effect of solar light is lowered only by 25%. In conclusion, we found four of the five light sources and the greenhouse usable for indoor daylight PDT. The greenhouse is beneficial when the weather outside is rainy or windy. Only insignificant ultraviolet B radiation (UVB) radiation passes through the greenhouse glass, so sun protection is not needed. 相似文献
100.
For the risk for spontaneous combustion in storage of biomass pellets to be assessed, it is important to know how prone the fuel is to self‐heating. There are traditional methods that are used to determine self‐heating characteristics of fuels, eg, basket heating tests. The results from basket heating tests indirectly give the reactivity from a series of tests at high temperatures. This paper presents a sensitive screening test procedure for biomass pellets using isothermal calorimetry for direct measurement of the heat production rate at typical bulk storage temperatures. This method can be used to directly compare the reactivity of different batches of biomass pellets. The results could be used, eg, by storage security managers to gain better knowledge of their fuels propensity for self‐heating and thereby for safer storage. A large number of tests have been performed to develop the test procedure presented. Different parameters, such as temperature, type of the test sample (powder/crushed or pellets), mass of test sample, and preheating time, have been varied. Furthermore, gas concentrations in the sample ampoule have been measured before and after some tests to study the oxygen consumption and the formation of CO and CO2. Three different types of pellets with different characteristics were tested to assess the variation in behaviour. Based on these tests, a screening test procedure is presented with a test temperature of 60°C, a sample size of 4 g, a 15‐minute preheating period at the test temperature, and 24‐hour test duration. 相似文献