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Fissile material dissolved in the molten salt is employed in molten salt reactor(MSR), which circulates through the primary loop. Considering the flow characteristic of fuel in MSR, the neutron poison calculation model such as Xe is different from traditional solid reactor. As an important neutron poison, 135Xe is free to migrate with the flow of molten salt in MSR. The helium bubble system of molten salt reactor can blow the fission products of krypton, xenon and other gases out of the reactor core to improve the neutron economy. The recent TENDL2021 nuclear data library estimates the thermal neutron absorption cross section of 135Xem, which is much higher than 135Xe thermal neutron absorption cross section. In order to predict the effect of xenon on core reactivity more accurately, the effect of 135Xem thermal neutron absorption cross section was added into the Xe poison model based on the lumped volume method. The migration model is made up of cover gas calculation model and xenon worth calculation model. In order to calculate the xenon worth, the loop void fraction was calculated firstly, and the loop void fraction was inserted into the xenon worth calculation model. According to the rate balance equations and mass transfer equations, the concentration of xenon in loop could be calculated to compute the xenon worth. Firstly, the model results considering the flow effect of fuel salt were verified with the experimental results of 8 MW molten salt reactor experiment (MSRE). As the results shown, with the increase of loop void fraction, the steadystate xenon worth increases first and decreases later, which is in good agreement with experimental results of MSRE. Then the influence of fuel salt types and 135Xem on steadystate xenon worth was considered in this paper. The steadystate xenon worth of the 233U system with and without 135Xem is made and compared to a 235U system, indicating that the influence of 135Xem on xenon worth cannot be ignored, which is much higher with the increase of power. Finally, the contribution of graphite, fuel salt and helium bubble to Xe worth was evaluated by the interaction between graphite and helium bubble, indicating that the interaction between helium bubble and graphite cannot be ignored.

Byline: Chen-Yu. Wu, Chih-Yi. Liu, You-Chen Serena. Liu Sir, The coexistence of vitiligo and frontal fibrosing alopecia, a distinct variant of lichen planus affecting hair follicles predominantly on the frontotemporal [...]

The resistivity of the sintered Cu thick film decreases with the weight percentage of the SiO2–ZnO–B2O3 additive in the mixing glass frits up to 50 wt%. As the weight percentage of the SiO2–ZnO–B2O3 additive in the mixing glass frits is over 50 wt%, the resistivity of the sintered Cu thick films is quite similar. The lowest resistivity (6.62 × 10−6 Ω‐cm) of the sintered Cu thick films occurs at 75 wt% of the SiO2–ZnO–B2O3 additive. Also, we observe the extensive glass phase framing around the large Cu grains in the Cu thick films sintered with low SiO2–ZnO–B2O3 additives (less than 50 wt%) narrows the cross‐section area of the electrical path. On the contrary, the round‐shaped glass phase solidified among the small Cu grains allows a larger cross‐section of the electrical path (a possible lower resistivity) for the Cu thick films sintered with higher SiO2–ZnO–B2O3 additives (larger than 50 wt%). The above results imply that the resistivity of the sintered Cu thick film correlates well with the microstructure (Cu grain size and the glass/Cu composite structure) of the sintered Cu thick films. Twin grain boundaries can clearly be observed in the sintered Cu thick films, especially for the Cu thick film sintered with the higher SiO2–ZnO–B2O3 additives. Owing to small Cu grains size and high density of Cu grain boundary, the probability of the grain boundaries with a high grain‐boundary energy in the Cu thick film sintered with high SiO2–ZnO–B2O3 additive would be much larger, comparing to that in the Cu thick film sintered with low SiO2–ZnO–B2O3 additive. Thus, more annealing twin boundaries formed in the Cu thick film sintered with high SiO2–ZnO–B2O3 additive. Hence, the formation of the twin boundary in the sintered Cu thick film helps reducing the resistivity of the sintered Cu films. [ABSTRACT FROM AUTHOR]

Objective * To establish the reference intervals of serum anti-Müllerian hormone (AMH) in healthy women of childbearing age in different age groups in Shanghai. Methods * A total of 239 healthy women of childbearing age, who accepted staff physical examination in International Peace Maternity and Child Health Hospital, Shanghai Jiao Tong University School of Medicine, during July 2019, were enrolled and detected for serum AMH level using chemiluminescence immunoassay. After the outlier exclusion, 234 subjects were finally included and divided into six age groups. The reference intervals of serum AMH in healthy women of childbearing age in different age groups in Shanghai were established. The natural logarithm of serum AMH level and age were fitted by quadratic regression model. Results * The reference interval of serum AMH level was expressed as M(P5-P95), which were 4.76 (0.96-14.17) ng/mL in women aged 19-24 years, 6.03 (1.38-16.56) ng/mL in women aged 25-29 years, 4.30 (0.95-10.73) ng/mL in women aged 30-34 years, 2.40 (0.33-9.27) ng/mL in women aged 35-39 years, 1.04 (0.05-4.00) ng/mL in women aged 40-44 years, and 0.21 (0.01-3.04) ng/ mL in women aged 45-49 years. After logarithmic transformation, serum AMH level and age could well obey the quadratic regression model (R²=0.502). Conclusion * The reference intervals of serum AMH level established for the first time in healthy women of child-bearing age in Shanghai may provide the basis for the evaluation of ovarian reserve function of women of different ages. [ABSTRACT FROM AUTHOR]

Featured Application: This work can be used in engineering and information applications. Multi-class classification is a very important technique in engineering applications, e.g., mechanical systems, mechanics and design innovations, applied materials in nanotechnologies, etc. A large amount of research is done for single-label classification where objects are associated with a single category. However, in many application domains, an object can belong to two or more categories, and multi-label classification is needed. Traditionally, statistical methods were used; recently, machine learning techniques, in particular neural networks, have been proposed to solve the multi-class classification problem. In this paper, we develop radial basis function (RBF)-based neural network schemes for single-label and multi-label classification, respectively. The number of hidden nodes and the parameters involved with the basis functions are determined automatically by applying an iterative self-constructing clustering algorithm to the given training dataset, and biases and weights are derived optimally by least squares. Dimensionality reduction techniques are adopted and integrated to help reduce the overfitting problem associated with the RBF networks. Experimental results from benchmark datasets are presented to show the effectiveness of the proposed schemes. [ABSTRACT FROM AUTHOR]

Summary: One up‐regulated host gene identified previously was found involved in the infection process of Bamboo mosaic virus (BaMV), a single‐stranded positive‐sense RNA virus. The full length cDNA of this gene was cloned by 5′ and 3′‐rapid amplification of cDNA ends and found to encode a polypeptide containing a conserved really interesting new gene (RING) domain and a transmembrane domain. The gene might function as an ubiquitin E3 ligase. We designated this protein in Nicotiana benthamiana as ubiquitin E3 ligase containing RING domain 1 (NbUbE3R1). Further characterization by using Tobacco rattle virus‐based virus‐induced gene silencing (loss‐of‐function) revealed that increased BaMV accumulation was in both knockdown plants and protoplasts. The gene might have a defensive role in the replication step of BaMV infection. To further inspect the functional role of NbUbE3R1 in BaMV accumulation, NbUbE3R1 was expressed in N. benthamiana plants. The wild‐type NbUbE3R1‐orange fluorescent protein (NbUbE3R1‐OFP), NbUbE3R1/△TM‐OFP (removal of the transmembrane domain) and NbUbE3R1/mRING‐OFP (mutation at the RING domain, the E2 interaction site) were transiently expressed in plants. NbUbE3R1 and its derivatives all functioned in restricting the accumulation of BaMV. The common feature of these constructs was the intact substrate‐interacting domain. Yeast two‐hybrid and co‐immunoprecipitation experiments used to determine the possible viral‐encoded substrate of NbUbE3R1 revealed the replicase of BaMV as the possible substrate. In conclusion, we identified an up‐regulated gene, NbUbE3R1 that plays a role in BaMV replication. [ABSTRACT FROM AUTHOR]

Recent research found that fine‐tuning pre‐trained models is superior to training models from scratch in just‐in‐time (JIT) defect prediction. However, existing approaches using pre‐trained models have their limitations. First, the input length is constrained by the pre‐trained models.Secondly, the inputs are change‐agnostic.To address these limitations, we propose JIT‐Block, a JIT defect prediction method that combines multiple input semantics using changed block as the fundamental unit. We restructure the JIT‐Defects4J dataset used in previous research. We then conducted a comprehensive comparison using eleven performance metrics, including both effort‐aware and effort‐agnostic measures, against six state‐of‐the‐art baseline models. The results demonstrate that on the JIT defect prediction task, our approach outperforms the baseline models in all six metrics, showing improvements ranging from 1.5% to 800% in effort‐agnostic metrics and 0.3% to 57% in effort‐aware metrics. For the JIT defect code line localization task, our approach outperforms the baseline models in three out of five metrics, showing improvements of 11% to 140%. [ABSTRACT FROM AUTHOR]

In this paper, an equi-section division method utilizing the symmetry property and amplitude approximation of a sinusoidal waveform to design a direct digital frequency synthesizer (DDFS) is proposed. The sinusoidal phase of a onequarter period is divided into equi-sections. The error value between each line segment value and the sinusoidal amplitude value is stored in a read-only memory (ROM) to reconstruct the real sinusoidal waveform. The upper/lower bound of the maximum error value stored in error-compensation ROM will be derived to determine the minimum required memory wordlength relative to the bit number of the equi-sections. In addition, the minimum size of the total ROMs can be computed according to the bit number of the equi-sections. Thus, the equi-section division method is implemented on a field programmable gate array (FPGA) development board. As a result, the total compression ratio of the DDFS using the equisection division method is superior to that of the DDFS using the traditional compression methods. The simulation and experimental results show that the proposed ROM compression method can effectively achieve a better compression ratio and lower complexity, compared with the DDFS using the traditional compression methods, without affecting the spectrum performance. [ABSTRACT FROM AUTHOR]