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Abstract: The measurement of the angle of a user’s head in a novel head tracker is presented. From the image of multi-light-sources the computer transforms the total positions into polar coordinates and determines the angle of the swinging head to improve the performance of mouse operation. Once the user has finished system adjustment and remained at the same distance, the user can precisely control the mouse to any position for any distance. This system can create the head’s dynamic motional space using the relative positions of multi-light-sources. If the user is closer to the monitor, the user will achieve better system performance. This is great improvement on the inaccuracy of previous head-control systems and the angles of user’s head swimming can control the speed of the cursor. This head tracker is more precise and has superior performance, especially for the icon clicking of a computer operation. [Copyright &y& Elsevier]

Several challenges exist in the analysis of the sodium-cooled fast reactor (SFR) core using computational fluid dynamics (CFD)codes. These include the intricate task of geometric modeling and mesh partitioning and the substantial computational resources required by CFD calculations. These challenges have been shown to create significant impediments to the practical analysis of the SFR core. This paper proposes a CFD scheme called the Parameterized Modeling and Automated Distributed Computing Approach (PM-ADC) to address the challenges. This approach includes a fuel assembly model tailored for the fast reactor core and incorporates parameterized geometric modeling coupled with a system to automate the distribution of parallel computing. The PM-ADC scheme is divided into two critical components: rapid preprocessing design and the generation of geometric models and meshes for core assemblies, enabled by Parameterized Modeling (PM). In contrast, the Automatic Distributed Computing (ADC) component is responsible for the enhancement of computing efficiency and resource utilization. This is achieved by the automatic allocation and distribution of CFD computing resources within a partitioned domain, resulting in the completion of CFD analyses for all fuel assemblies at full height in a significantly reduced timeframe. The performance of the PM-ADC scheme is analyzed on CFD calculations on representative areas of 81 fuel assemblies within the core of the Chinese Experimental Fast Reactor (CEFR). The results show that the PM-ADC scheme can accurately and efficiently simulate the flow and heat transfer characteristics of the CEFR fuel assembly, demonstrating its potential for high-fidelity analysis of large engineering systems. The study's findings also provide new insights and tools for the ongoing development and analysis of SFRs, contributing to the evolution of nuclear reactor design and safety. [ABSTRACT FROM AUTHOR]

Abstract: To better understand the photosynthesis under stress, the effect of cadmium on carbon assimilation and chloroplast ultrastructure of a newly found Zn/Cd hyperaccumulator Picris divaricata in China was investigated in solution culture. The shoot and root Cd concentrations increased with increase in Cd supply, reaching maxima of 1109 and 5604mgkg−1 dry weight at 75μM Cd, respectively. As Cd supply to P. divaricata increased, the shoot and root dry weight, leaf water content (except 75μM Cd), concentrations of chlorophyll a and b, chlorophyll a/b ratio and the concentration of carotenoids were not depressed at high Cd. However, the stomatal conductance, transpiration rate, net photosynthetic rate and intercellular CO2 concentration were significantly affected when the Cd concentration reached 10, 10, 25 and 75μM, respectively. Meanwhile, carbonic anhydrase (CA; EC 4.2.1.1) activity and Rubisco (EC 4.1.1.39) content reached maxima in the presence of 50 and 5μM Cd, respectively. In addition, CA activity correlated positively with shoot Cd in plants treated with Cd at a range of 0–50μM. Moreover, the activities of NADP+-glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.13), Rubisco and fructose-1, 6-bisphosphatase (EC 3.1.3.11) were not significantly suppressed by increased Cd supply. Although the mesophyll cell size was reduced, chloroplast ultrastructure remained intact at the highest Cd treatment. Our finding revealed that P. divaricata chloroplast and the enzymes of carbon assimilation tolerate high levels of Cd, demonstrating its potential in possible application in phytoremediation. [Copyright &y& Elsevier]

Abstract: Chondrogenic potential of human adipose derived stem cells (hASCs) makes them a possible source of seeding cells for cartilage tissue engineering. In this study, chondrogenic differentiation of hASCs induced by transduction with replication-deficient adenovirus carrying human transforming growth factor beta2 (Ad5-hTGF beta2) was demonstrated by RT-PCR, immunohistochemistry staining, biochemical and western blot analysis. To evaluate if the in vitro differentiated hASCs could keep their chondrocytic phenotype and produce neo-cartilage in vivo, predifferentiated hASCs were seeded in different scaffolds and implanted in subcutaneous pockets on the dorsum of nude mice. After 4 and 12 weeks culture in vivo, specimens were harvested and examined by histological and immunohistochemical analysis, cartilage-like tissue formation was only found in alginate gel and PLGA/alginate compound groups, in PLGA group, fibrous tissues and angiogenesis ingrowth were observed. These findings demonstrated that adenovirus-mediated hTGF beta2 gene transfer could induce hASCs into a chondrogenic lineage in vitro, however, this predifferentiation did not guarantee ectopic cartilage formation in vivo unless appropriate three-dimensional scaffolds were used as the cell carry vehicles. [Copyright &y& Elsevier]