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11.
12.
The distribution of plasmalogenase for the hydrolysis of 1-alkenyl-2-acyl-sn-glycero-3-phosphoethanolamine (plasmenylethanolamine) in the subcellular fractions of guinea pig tissues was examined. Plasmalogenase
activity was found in high abundance in the cytosolic fractions of the brain and the heart. Assessment of microsomal marker
enzyme activities in the cytosolic fraction revealed that plasmalogenase activity in the cytosol was not due to microsomal
contaminations. The characteristics of the cytosolic plasmalogenase were very similar to the microsomal enzyme with respect
to the pH profile of the reaction, the presence of divalent cations and Km values for plasmenylethanolamine. However, the cytosolic enzyme was slightly less stable at 55°C than the microsomal enzyme.
Cytosolic enzyme activity was eluted as a broad peak in Sepharose 6B chromatography with an average molecular weight of 250,000.
Our results demonstrate that most of brain plasmalogenase activity is soluble which makes the brain cytosol an excellent source
to initiate the purification of this enzyme. 相似文献
13.
Ruijia Zhang Zengqi Huang Weipeng Chen Benzheng Lyu Hong Zhang Xinjun He Xiaotian Hu Yanlin Song Wallace C. H. Choy 《Advanced functional materials》2023,33(5):2210063
Advancing hole transport layers (HTL) to realize large-area, flexible, and high-performance perovskite solar cells (PSCs) is one of the most challenging issues for its commercialization. Here, a self-assembled gradient Ti3C2Tx MXene incorporated PEDOT:PSS HTL is demonstrated to achieve high-performance large-area PSCs by establishing half-caramelization-based glucose-induced MXene redistribution. Through this process, the Ti3C2Tx MXene nanosheets are spontaneously dispersed and redistributed at the top region of HTL to form the unique gradient distribution structure composed of MXene:Glucose:PEDOT:PSS (MG-PEDOT). These results show that the MG-PEDOT HTL not only offers favorable energy level alignment and efficient charge extraction, but also improves the film quality of perovskite layer featuring enlarged grain size, lower trap density, and longer carrier lifetime. Consequently, the power conversion efficiency (PCE) of the flexible device based on MG-PEDOT HTL is increased by 36% compared to that of pristine PEDOT:PSS HTL. Meanwhile, the flexible perovskite solar minimodule (15 cm2 area) using MG-PEDOT HTL achieve a PCE of 17.06%. The encapsulated modules show remarkable long-term storage stability at 85 °C in ambient air (≈90% efficiency retention after 1200 h) and enhanced operational lifetime (≈90% efficiency retention after 200 h). This new approach shows a promising future of the self-assembled HTLs for developing optoelectronic devices. 相似文献
14.
15.
A paraboliclike quantum well structure can be used to produce polarization-insensitive waveguide type modulators. We propose the use of interdiffusion of AlGaAs/GaAs quantum wells to achieve the parabolic well shape. Criteria to achieve the paraboliclike quantum wells by interdiffusion are discussed. The theoretical results indicate that interdiffused quantum wells can produce equal eigenstate spacing, polarization insensitive Stark shifts, and modulation similar to an ideal parabolic quantum well. Three procedures are also proposed to develop polarization-insensitive on and off states in paraboliclike interdiffused quantum wells. The modulation depth is compatible with that of the measured parabolic quantum wells. For diffused quantum wells one can take advantage of using an as-grown rectangular quantum well with postgrowth thermal processing. These features demonstrate that an interdiffused quantum well structure can be used to produce a polarization-insensitive electroabsorptive modulator. 相似文献
16.
Efficiently extendible mappings for balanced data distribution 总被引:2,自引:0,他引:2
In data storage applications, a large collection of consecutively numbered data “buckets” are often mapped to a relatively small collection of consecutively numbered storage “bins.” For example, in parallel database applications, buckets correspond to hash buckets of data and bins correspond to database nodes. In disk array applications, buckets correspond to logical tracks and bins correspond to physical disks in an array. Measures of the “goodness” of a mapping method include:
- Thetime (number of operations) needed to compute the mapping.
- Thestorage needed to store a representation of the mapping.
- Thebalance of the mapping, i.e., the extent to which all bins receive the same number of buckets.
- The cost ofrelocation, that is, the number of buckets that must be relocated to a new bin if a new mapping is needed due to an expansion of the number of bins or the number of buckets.
17.
Allan James Samantha Low Choy Kerrie Mengersen 《Environmental Modelling & Software》2010,25(1):129-145
Expert elicitation is the process of retrieving and quantifying expert knowledge in a particular domain. Such information is of particular value when the empirical data is expensive, limited or unreliable. This paper describes a new software tool, called Elicitator, which assists in quantifying expert knowledge in a form suitable for use as a prior model in Bayesian regression. Potential environmental domains for applying this elicitation tool include habitat modelling, assessing detectability or eradication, ecological condition assessments, risk analysis and quantifying inputs to complex models of ecological processes. The tool has been developed to be user-friendly, extensible and facilitate consistent and repeatable elicitation of expert knowledge across these various domains. We demonstrate its application to elicitation for logistic regression in a geographically based ecological context. The underlying statistical methodology is also novel, utilizing an indirect elicitation approach to target expert knowledge on a case-by-case basis. For several elicitation sites (or cases), experts are asked simply to quantify their estimated ecological response (e.g. probability of presence), and its range of plausible values, after inspecting (habitat) covariates via GIS. 相似文献
18.
Joanna J.J. Wang Jennifer S.K. ChanS.T. Boris Choy 《Computational statistics & data analysis》2011,55(1):852-862
This paper studies a heavy-tailed stochastic volatility (SV) model with leverage effect, where a bivariate Student-t distribution is used to model the error innovations of the return and volatility equations. Choy et al. (2008) studied this model by expressing the bivariate Student-t distribution as a scale mixture of bivariate normal distributions. We propose an alternative formulation by first deriving a conditional Student-t distribution for the return and a marginal Student-t distribution for the log-volatility and then express these two Student-t distributions as a scale mixture of normal (SMN) distributions. Our approach separates the sources of outliers and allows for distinguishing between outliers generated by the return process or by the volatility process, and hence is an improvement over the approach of Choy et al. (2008). In addition, it allows an efficient model implementation using the WinBUGS software. A simulation study is conducted to assess the performance of the proposed approach and its comparison with the approach by Choy et al. (2008). In the empirical study, daily exchange rate returns of the Australian dollar to various currencies and daily stock market index returns of various international stock markets are analysed. Model comparison relies on the Deviance Information Criterion and convergence diagnostic is monitored by Geweke’s convergence test. 相似文献
19.
Acoustic emission (AE) sensors have been fabricated using polarized polyvinylidene fluoride/trifluoroethylene (P(VDF-TrFE)) piezoelectric copolymer films. The acoustic and electromechanical properties of the copolymers have been determined using the ultrasonic immersion technique and the resonance technique, respectively. The P(VDF-TrFE) AE sensors have been calibrated according to the ASTM standard and evaluated for potential application in the detection of AE in glass fiber reinforced polypropylene (GFPP). A ceramic AE sensor also has been fabricated using lead zirconate titanate (PZT) 7A piezoelectric ceramic and its sensitivity and performance are reported as well. The copolymer sensors do not show resonance peaks of the ceramic sensor and have adequate sensitivity. They can reproduce AE signals accurately without giving artifacts and have potential use in commercial AE systems. 相似文献
20.
This paper proposes an adaptive robust fuzzy control scheme for path tracking of a wheeled mobile robot with uncertainties.
The robot dynamics including the actuator dynamics is considered in this work. The presented controller is composed of a fuzzy
basis function network (FBFN) to approximate an unknown nonlinear function of the robot complete dynamics, an adaptive robust
input to overcome the uncertainties, and a stabilizing control input. The stability and the convergence of the tracking errors
are guaranteed using the Lyapunov stability theory. When the controller is designed, the different parameters for two actuator
models in the dynamic equation are taken into account. The proposed control scheme does not require the accurate parameter
values for the actuator parameters as well as the robot parameters. The validity and robustness of the proposed control scheme
are demonstrated through computer simulations.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献