When a nuclear reactor with rectangular fuel assemblies runs for a long time, impurities and debris may be taken into coolant channels, which may cause flow blockage, and the blocked fuel assemblies ...might be destroyed. Therefore, the purpose of this study is to perform a thermal-hydraulic analysis of a rectangular fuel assembly by STAR-CCM+, under the condition of one subchannel with 80% blockage ratio. A rectangular fuel assembly of the International Atomic Energy Agency (IAEA) 10 MW material test reactor (MTR) is chosen. In view of the gasket material taken into the coolant channel is close to the single side of the coolant channel, in the flow blockage accident of the Oak Ridge Research Reactor (ORRR), a new blockage category called single side blockage is attempted. The blockage positions include inlet, middle and outlet, and the blockage is set as a cuboid. It is found by simulations that the blockage redistributes the mass flow rate, and large vortices appear locally. The peak temperature of the cladding is maximum, when the blockage is located at the single side of the coolant channel inlet, and no boiling occurs in all blockage cases. Moreover, as the height of the blockage increases, the damage caused by the blockage increases slightly.
Functional Choline Phosphate Polymers Hu, Gaojie; Emrick, Todd
Journal of the American Chemical Society,
02/2016, Volume:
138, Issue:
6
Journal Article
Peer reviewed
Zwitterionic polymers have been widely implemented in surface modification and as biomaterials that exhibit exceptional hydrophilicity, biocompatibility, and antifouling properties. However, a wider ...breadth of applications for polymer zwitterions is hindered by their inherent lack of functionality, requiring the integration of chain-end functionality or incorporation of functional comonomers along the polymer chain. Here we demonstrate the facile placement of unsaturated groups directly into zwitterionic methacrylate monomers, specifically choline phosphate structures, and show the utility of these monomers in controlled free radical polymerization. These versatile functional zwitterions are converted easily to polymer prodrugs, hydrogels, and other derivatives that establish the versatility of this novel materials platform.
MYB transcriptional factors, characterized by the presence of conserved DNA‐binding domains (BDs) (MYB domain), are involved in diverse processes including plant growth, development, metabolic and ...stress responses. In this study, a new R2R3‐type MYB gene, NbPHAN (Nicotiana benthamiana PHANTASTICA), was identified in N. benthamiana. The NbPHAN encodes a protein of 362 amino acids and shares high sequence identities with the AS1‐RS2‐PHANs (ARPs) from other plant species. The NbPHAN protein targets to and forms homodimers in the nucleus. The MYB domain and C‐terminal region of NbPHAN determine its subcellular localization and homodimerization, respectively. Using virus‐induced gene silencing, we showed that the NbPHAN‐silenced leaves exhibited severe downward curling and abnormal growth of blades along the main veins through suppressing the expression of the NTH20 gene. In addition, we found NbPHAN plays an important role in drought tolerance. The NbPHAN‐silenced plants exhibited severe wilting and increased rate of water loss than that found in the non‐silenced plants when growing under the water deficit condition. Although abscisic acid accumulation was not altered in the NbPHAN‐silenced plants as compared with that in the non‐silenced plants, several other stress‐inducible genes were clearly repressed under the water deficit condition. Our results provide strong evidence that other than controlling leaf development, the ARP genes can also regulate plant tolerance to drought stress.
Virus isolates HaNHK7 and HaNHK8 were obtained from tomato plants showing leaf curl symptoms in Hainan Province of China. The complete DNA sequences of both isolates were determined to be 2748 ...nucleotides, with all the characteristic features of begomovirus genome organization. The two isolates share 99.8% identity with each other but have <88.3% nucleotide sequence identity with other begomoviruses. Consequently, HaNHK7 and HaNHK8 are considered to be isolates of a novel Begomovirus species, for which the name Tomato leaf curl Hainan virus (ToLCHnV) is proposed. ToLCHnV is most closely related to Papaya leaf curl China virus (PaLCuCNV, AJ558117) (88.3% in total nucleotide sequences). However, the AC2 gene more resembles that of Ageratum leaf curl virus (ALCuV, AJ851005) and AC1 and AC4 genes resemble those of Tomato leaf curl Vietnam virus (ToLCVV, AF264063). Sequence analyses suggest that ToLCHnV may have arisen by recombination between viruses related to PaLCuCNV, ALCuV and ToLCVV. Neither the DNA‐B component nor the DNA‐β molecule was found to be associated with ToLCHnV isolates.
Pyrethroids have been reported to interact synergistically when co‐exposed with azoles fungicides in different organisms. In the present study, we investigated the mixture toxicity of fenvalerate ...(FEN) and triadimefon (TDF) toward embryos of Gobiocypris rarus after 96 h exposure. Results demonstrated that TDF enhanced the acute toxicity of FEN. Exposure to binary mixtures of FEN and TDF resulted in synergistic responses of endocrine disruption by inducing the transcripts of several genes including vtg, erα, erβ1, erβ2, cyp19a, cyp1a, cyp4, cyp11a, gnrh3, gnrhr1a, star, and dmrt1. Furthermore, FEN and TDF mixture increased the VTG level and aromatase activity in rare minnow embryos. FEN and TDF co‐exposure also regulated the mRNA of vezf, hsp70, p53, gadd45α, induced the synthesis of ROS and activity of GST, suggesting the synergistic potential of oxidative stress induced by FEN and TDF co‐exposure. The results indicated that binary mixtures of FEN and TDF could simultaneously induce endocrine disruption and oxidative stress in a synergistic manner during rare minnow embryo development.
When a nuclear reactor with rectangular fuel assemblies runs for a long time, impurities and debris maybe taken into coolant channels, which may cause flow blockage, and the blocked fuel assemblies ...mightbe destroyed. Therefore, the purpose of this study is to perform a thermal-hydraulic analysis of a rectangular fuel assembly by STAR-CCMþ, under the condition of one subchannel with 80% blockage ratio. Arectangular fuel assembly of the International Atomic Energy Agency (IAEA) 10 MW material test reactor(MTR) is chosen. In view of the gasket material taken into the coolant channel is close to the single side ofthe coolant channel, in the flow blockage accident of the Oak Ridge Research Reactor (ORRR), a newblockage category called single side blockage is attempted. The blockage positions include inlet, middleand outlet, and the blockage is set as a cuboid. It is found by simulations that the blockage redistributesthe mass flow rate, and large vortices appear locally. The peak temperature of the cladding is maximum,when the blockage is located at the single side of the coolant channel inlet, and no boiling occurs in allblockage cases. Moreover, as the height of the blockage increases, the damage caused by the blockageincreases slightly KCI Citation Count: 0
The purpose of this study was to investigate the role of urea-N recycling, rumen bacterial community, and rumen epithelial gene expression in nitrogen utilization of calves. Here, 12 Holstein calves ...were divided into two dietary treatments: a high-protein diet (HP, 173 g/kg), and a low-protein diet (LP, 125 g/kg). Urea-N kinetics was evaluated using urea-
15
N
15
N isotope labeling method. Gene expression in rumen epithelium and liver, bacterial diversity, and metabolites in rumen were characterized using transcriptomic, Illumina HiSeq-based 16S rRNA, and LC/QTOF-MS-based metabolomics, respectively. We demonstrated that the bone weight, dressing percentage, and nitrogen utilization efficiency (NUE) increased in calves fed HP compared with LP. The urea synthesized, eliminated in urine, and return to ornithine cycle were higher in calves fed HP than LP, while the urea-N reused for anabolism were the opposite. Differentially expressed genes participated in amino acid metabolism and molecular transport in rumen epithelium. The increased abundance of bacteria and metabolites involved in protein and/or amino acid metabolism reflected the larger protein utilization in rumen of calves fed HP. In conclusion, the urea-N recycling could not fully compensate for the reduced NUE caused by N deficiency. Rumen bacteria and rumen epithelial metabolism contribute to improving NUE of calves.
When a nuclear reactor with rectangular fuel assemblies runs for a long time, impurities and debris may be taken into coolant channels, which may cause flow blockage, and the blocked fuel assemblies ...might be destroyed. Therefore, the purpose of this study is to perform a thermal-hydraulic analysis of a rectangular fuel assembly by STAR-CCM+, under the condition of one subchannel with 80% blockage ratio. A rectangular fuel assembly of the International Atomic Energy Agency (IAEA) 10 MW material test reactor (MTR) is chosen. In view of the gasket material taken into the coolant channel is close to the single side of the coolant channel, in the flow blockage accident of the Oak Ridge Research Reactor (ORRR), a new blockage category called single side blockage is attempted. The blockage positions include inlet, middle and outlet, and the blockage is set as a cuboid. It is found by simulations that the blockage redistributes the mass flow rate, and large vortices appear locally. The peak temperature of the cladding is maximum, when the blockage is located at the single side of the coolant channel inlet, and no boiling occurs in all blockage cases. Moreover, as the height of the blockage increases, the damage caused by the blockage increases slightly.
•Carcass quality of 2.5 y Yaoshan white goats is higher than that of 2 y or 1.5 y.•Yaoshan white goat meat is a high-quality protein source.•MF of triceps brachii and gluteus is healthier than that ...of longissimus thoracis for consumer.•IMF deposition is related to the expression of PPARγ, LPL, SREBP-1c, and ACACA.
We investigated the effect of slaughter age on carcass and meat quality, and compared the physicochemical traits and mRNA levels of lipid metabolism-related genes in triceps brachii (TB), longissimus thoracis (LT) and gluteus (GL) muscles of fifteen castrated Yaoshan white goats. We found that goats slaughtered at 2.5 y had higher final body, carcass, meat, and bone weights than at 1.5 y or 2 y. GL had higher crude protein concentration. Amino acids and fatty acids differed among the three muscles. The expression of PPARγ, LPL, SREBP-1c, and ACACA were the highest in LT, followed by GL and TB, which was consistent with the IMF content. Overall, carcass quality was higher in goats slaughtered at 2.5 y. From a consumer health perspective, IMF of TB and GL muscles displayed better quality attributes (lower MUFA/PUFA, higher PUFA, and higher PUFA/SFA ratio) than LT. IMF deposition was related to the expression of PPARγ, LPL, SREBP-1c, and ACACA.
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