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101.
We introduced a non-symmetric tensor product of any two states or any two representations of Cuntz–Krieger algebras associated with a certain non-cocommutative comultiplication in our previous work. In this paper, we show that a certain set of KMS states is closed with respect to the tensor product. From this, we obtain formulae of tensor products of type III factor representations of Cuntz–Krieger algebras which are different from results of the tensor product of factors of type III.  相似文献   
102.
103.
104.
One pot double click strategy containing strain-promoted click-reaction followed by 6π-azaelectrocyclization (RIKEN click reaction) has worked well in the synthesis of multivalent homogeneous and heterogeneous N-glycoalbumins. We have slightly changed the structure of linker unsaturated aldehyde used in this method. As a result it can be easily synthesized from commercially available material and furthermore, the enhancement of its reactivity towards both click-reactions was observed. The data described in this Communications facilitate the usage of the double click strategy as a general method for the synthesis of a variety of neo-N-glycoproteins.  相似文献   
105.
LetM(n) be the algebra of alln×n complex matrices. We consider a dynamical system onM(n) defined by the vector fieldV(X)=[[X *,X],X], (X M(n)). It arises as the gradient flow for two kinds of variational problems onM(n). Given anyX 0 M(n), letX(t) be the trajectory starting atX 0. We study the global behavior ofX(t) ast . We show that, ifX 0 is semisimple, thenX(t) converges exponentially to a normal matrix. IfX 0 is not semisimple, then the behavior ofX(t) is completely different and difficult to analyze. We give some results also in this case. Furthermore, we discuss about a center manifold approach to our dynamical system.  相似文献   
106.
类金刚石多层膜在不同环境下的摩擦磨损行为研究   总被引:4,自引:2,他引:4  
采用等离子体辅助化学气相沉积法在单晶硅表面制备由硬/软亚层交替构成的类金刚石多层膜,通过调整工艺参数获得亚层厚度在25~1000nm之间的DLC多层膜,采用球-盘摩擦磨损试验机探讨了DLC多层膜在真空、氧气及干燥空气下的摩擦磨损行为.结果表明,在不同摩擦环境下,多层结构对DLC多层膜的摩擦系数影响较小,但对其磨损率影响较大.多层结构可以有效抑制DLC膜的磨损,特别是在氧气和干燥空气环境中,DLC多层膜的磨损率明显低于DLC单层膜.特定亚层厚度的DLC多层膜在不同摩擦环境中均具有稳定的耐磨性能,磨损率约在10^-8mm^3/Nm数量级.  相似文献   
107.
Proteolytic processing of the amyloid precursor protein (APP) by β-secretase and γ-secretase leads to the generation and deposition of amyloid β (Aβ) in Alzheimer’s disease (AD). N-terminally or C-terminally truncated Aβ variants have been found in human cerebrospinal fluid and cultured cell media using immunoprecipitation and mass spectrometry. Unfortunately, the profile of plasma Aβ variants has not been revealed due to the difficulty of isolating Aβ from plasma. We present here for the first time studies of Aβ and related peptides in human plasma. Twenty-two Aβ-related peptides including novel peptides truncated before the β-secretase site were detected in human plasma and 20 of the peptides were identified by tandem mass spectrometry. Using an internal standard, we developed a quantitative assay for the Aβ-related peptides and demonstrated plasma dilution linearity and the precision required for their quantitation. The present method should enhance the understanding of APP processing and clearance in AD progression.  相似文献   
108.

Background

The prognostic implications of late gadolinium enhancement (LGE) have been evaluated in ischemic and non-ischemic cardiomyopathies. The present study analyzed LGE distribution in patients with end-stage hypertrophic cardiomyopathy (ES-HCM) and with dilated cardiomyopathy (DCM), and tried to identify high risk patients in DCM.

Methods

Eleven patients with ES-HCM and 72 with DCM underwent cine- and LGE-cardiac magnetic resonance and ultrasound cardiography. The patient outcome was analyzed retrospectively for 5 years of follow-up.

Results

LGE distributed mainly in the inter-ventricular septum, but spread more diffusely into other left ventricular segments in patients with ES-HCM and in a certain part of patients with DCM. Thus, patients with DCM can be divided into three groups according to LGE distribution; no LGE (n = 24), localized LGE (localized at septum, n = 36), and extensive LGE (spread into other segments, n = 12). Reverse remodeling occurred after treatment in patients with no LGE and with localized LGE, but did not in patients with extensive LGE and with ES-HCM. The event-free survival rate for composite outcome (cardiac death, hospitalization for decompensated heart failure or ventricular arrhythmias) was lowest in patients with extensive LGE (92%, 74% and 42% in no LGE, localized LGE, and extensive LGE, p = 0.02 vs. no LGE), and was comparable to that in patients with ES-HCM (42%).

Conclusions

In DCM, patients with extensive LGE showed no functional recovery and the lowest event-free survival rate that were comparable to patients with ES-HCM. The analysis of LGE distribution may be valuable to predict reverse remodeling and to identify high-risk patients.  相似文献   
109.
This paper presents a new type of ozone-assisted catalysis for toluene decomposition. The different catalytic activities of ZSM-5 and Ag/ZSM-5 were incorporated into a layered catalyst with a tandem configuration. Instead of increasing the amount of metal catalyst, the layered catalyst was formed, which had an equal amount of bare ZSM-5 and Ag/ZSM-5 and could achieve both high toluene conversion and CO2 selectivity concurrently. The properties of each catalyst were evaluated with respect to toluene conversion, formation of intermediates, CO2 selectivity and ozone demand factor. The bare ZSM-5 exhibited higher toluene conversion than the Ag/ZSM-5, while its activity toward deep oxidation was limited. However, the Ag/ZSM-5 was found to be effective for the deep oxidation of reaction intermediates (HCOOH and CO). Separate oxidation tests with HCOOH and CO revealed that the ZSM-5-supported Ag nanoparticles could oxidize the HCOOH and CO in the absence of ozone, which was not possible with the bare ZSM-5. Plausible pathways for the oxidation of toluene with O3 over ZSM-5 and Ag/ZSM-5 were proposed based on the experimental evidence.  相似文献   
110.
Previous studies have shown that interference between fast waves and slow waves can lead to observed negative dispersion in cancellous bone. In this study, the effects of overlapping fast and slow waves on measurements of the apparent attenuation as a function of propagation distance are investigated along with methods of analysis used to determine the attenuation properties. Two methods are applied to simulated data that were generated based on experimentally acquired signals taken from a bovine specimen. The first method uses a time-domain approach that was dictated by constraints imposed by the partial overlap of fast and slow waves. The second method uses a frequency-domain log-spectral subtraction technique on the separated fast and slow waves. Applying the time-domain analysis to the broadband data yields apparent attenuation behavior that is larger in the early stages of propagation and decreases as the wave travels deeper. In contrast, performing frequency-domain analysis on the separated fast waves and slow waves results in attenuation coefficients that are independent of propagation distance. Results suggest that features arising from the analysis of overlapping two-mode data may represent an alternate explanation for the previously reported apparent dependence on propagation distance of the attenuation coefficient of cancellous bone.  相似文献   
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