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201.
Thymosin β4 (Tβ4) was extracted forty years agofrom calf thymus. Since then, it has been identified as a G-actin binding protein involved in blood clotting, tissue regeneration, angiogenesis, and anti-inflammatory processes. Tβ4 has also been implicated in tumor metastasis and neurodegeneration. However, the precise roles and mechanism(s) of action of Tβ4 in these processes remain largely unknown, with the binding of the G-actin protein being insufficient to explain these multi-actions. Here we identify for the first time the important role of Tβ4 mechanism in ferroptosis, an iron-dependent form of cell death, which leads to neurodegeneration and somehow protects cancer cells against cell death. Specifically, we demonstrate four iron2+ and iron3+ binding regions along the peptide and show that the presence of Tβ4 in cell growing medium inhibits erastin and glutamate-induced ferroptosis in the macrophage cell line. Moreover, Tβ4 increases the expression of oxidative stress-related genes, namely BAX, hem oxygenase-1, heat shock protein 70 and thioredoxin reductase 1, which are downregulated during ferroptosis. We state the hypothesis that Tβ4 is an endogenous iron chelator and take part in iron homeostasis in the ferroptosis process. We discuss the literature data of parallel involvement of Tβ4 and ferroptosis in different human pathologies, mainly cancer and neurodegeneration. Our findings confronted with literature data show that controlled Tβ4 release could command on/off switching of ferroptosis and may provide novel therapeutic opportunities in cancer and tissue degeneration pathologies.  相似文献   
202.
Column‐Slab Joints for Spun Concrete Columns In this paper joints consisting of high capacity spun concrete columns with reinforcement ratios up to 14,7% and slabs made of normal strength concrete are discussed. The main focus was put on the load transfer from the columns through the concrete slab. In all tests the reinforcement of the columns in the joints was not continuous. For spun concrete columns an optimized solution using a high strength core is presented. The conventional joints and the joints using a high strength core are compared in experimental tests. The results showed that the new joint design is capable of transferring higher loads and reduce the deformations in the slab. On the basis of the experimental data a model was developed, which provides simple design equations for such joints.  相似文献   
203.
大多数工程师都知道现有三种基本的FPGA技术:反熔丝、FLASH和SRAM.其中,SRAM是迄今为止应用范围最广的架构,主要因为它具有可重编程能力,而反熔丝FPGA只提供一次可编程(OTP)方案.  相似文献   
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Two ELISA kits were employed to detect staphylococcal enterotoxin A, B, C and D in foods to which enterotoxin had been added or which had been artificially contaminated with enterotoxin-producing strains of Staphylococcus aureus. The sensitivity was satisfactory, and enterotoxins were detected by both ELISA kits in all positive samples. Weak positive reactions with one ELISA kit caused some difficulties in evaluation of samples. Enterotoxins A, B and C detected in small amounts (2-22 ng/ml) in minced fried beef were not detectable after heating at 80 degrees C, whereas enterotoxin D detected in considerably greater amounts (783 ng/ml) was reduced to 0.4% of this amount.  相似文献   
207.

Object

The goal of this study was to develop a comprehensive magnetic resonance (MR) data analysis framework for handling very large datasets with user-friendly tools for parallelization and to provide an example implementation.

Materials and methods

Commonly used software packages (AFNI, FSL, SPM) were connected via a framework based on the free software environment R, with the possibility of using Nvidia CUDA GPU processing integrated for high-speed linear algebra operations in R. Three hundred single-subject datasets from the 1,000 Functional Connectomes project were used to demonstrate the capabilities of the framework.

Results

A framework for easy implementation of processing pipelines was developed and an R package for the example implementation of Fully Exploratory Network ICA was compiled. Test runs on data from 300 subjects demonstrated the computational advantages of a processing pipeline developed using the framework compared to non-parallelized processing, reducing computation time by a factor of 15.

Conclusion

The feasibility of computationally intensive exploratory analyses allows broader access to the tools for discovery science.  相似文献   
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209.
Sliding-corrosion phenomena play a crucial role in reducing the lifetime of tubings in the oil production industry. The aim of the present work is to develop and apply a close-to-reality test rig to describe the tribological performance of low-alloyed Carbon-steel (C-steel) under sliding-corrosion conditions in O2-free environment. The proposed test rig is highly relevant for the oil production industry and has been designed at the Austrian Competence Center for Tribology (AC²T). The benefit of this equipment is that it allows the setting of the CO2 atmosphere at a certain partial pressure while simultaneously varying the pH-value, Cl? ion concentration, and temperature of the electrolyte solution. Pure corrosion phenomena are investigated within a designed coupon box where conditions of steam, electrolyte injection, static, and dynamic flow are controlled. In addition to the corrosive environment, a tribological reciprocating sliding contact is implemented between tubing segments and coupling samples. Within this study, a commercially available low-alloyed C-steel was selected as base material for the tubing, which was tribologically stressed under reciprocating sliding contact against spray metal coated couplings. The results show a high influence of the steel microstructure on the performance of low-alloyed C-steel tubings under sliding-corrosion. Additionally, the dominant damage mechanisms that are observed in real field applications could be successfully reproduced by experimental simulation using this newly designed close-to-reality test rig.  相似文献   
210.
In this paper, we present a new approach for the enhancement of the bone proliferation rate by electrostimulation in the acetabular region. Based on the complex tissue structure in this area, the electric field distributions were computed by numerical means using a model based on high-resolution computed tomography scans of the acetabular area. This results in a complex, nonlinear, and discrete optimization problem. Therefore, an adapted algorithm was developed to reduce the computational effort in the order of several magnitudes. We divided the procedure into two stages: data extraction and a subsequent optimization process. The used optimization algorithm utilizes an evolutionary concept and a multidimensional definition of optimality for different, partly contradictive objective functions. Finally, we present first optimization results for different stimulation situations.   相似文献   
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