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Lithium and Beryllium in the Gaia-Enceladus Galaxy [article]

Paolo Molaro, Gabriele Cescutti, Xiaoting Fu
2020 arXiv   pre-print
is a 7 Li destruction over the long stellar lifetimes by mechanisms such as microscopic diffusion (Korn et al. 2006) , rotational mixing (Pinsonneault et al. 1998) , or pre-main-sequence depletion (Fu  ... 
arXiv:2006.00787v1 fatcat:oepb2tymzfatdhwtqu3gk74cuq

From the cosmological Li problem to the Galactic Li evolution [article]

Xiaoting Fu
2020 arXiv   pre-print
Fig. 1 . 1 Mind map on Li studies in astrophysics. stars, in Fu et al., (2015) we propounded a stellar model to solve the problem.  ...  In Fu et al., (2018) we select main sequence stars with UVES/VLT spectra from the Gaia − ES O survey and use their [α/Fe] abundance to separate them into the Galactic thin and thick disc stars.  ... 
arXiv:2006.02287v1 fatcat:4yfesieepbgpxbygnggd2btx4u

Graph-based Cooperative Caching in Fog-RAN [article]

Xiaoting Cui, Yanxiang Jiang, Xuan Chen, Fu-Chun Zheng, Xiaohu You
2018 arXiv   pre-print
In this paper, the cooperative caching problem in fog radio access networks (F-RAN) is investigated. To maximize the incremental offloaded traffic, we formulate the clustering optimization problem with the consideration of cooperative caching and local content popularity, which falls into the scope of combinatorial programming. % and is NP-hard. We then propose an effective graph-based approach to solve this challenging problem. Firstly, a node graph is constructed with its vertex set
more » ... ng the considered fog access points (F-APs) and its edge set reflecting the potential cooperations among the F-APs. %whether the F-APs the distance and load difference among the F-APs. Then, by exploiting the adjacency table of each vertex of the node graph, we propose to get the complete subgraphs through indirect searching for the maximal complete subgraphs for the sake of a reduced searching complexity. Furthermore, by using the complete subgraphs so obtained, a weighted graph is constructed. By setting the weights of the vertices of the weighted graph to be the incremental offloaded traffics of their corresponding complete subgraphs, the original clustering optimization problem can be transformed into an equivalent 0-1 integer programming problem. The max-weight independent subset of the vertex set of the weighted graph, which is equivalent to the objective cluster sets, can then be readily obtained by solving the above optimization problem through the greedy algorithm that we propose. Our proposed graph-based approach has an apparently low complexity in comparison with the brute force approach which has an exponential complexity. Simulation results show the remarkable improvements in terms of offloading gain by using our proposed approach.
arXiv:1806.09095v1 fatcat:bptjeajl4vfhdi7hbq24qip7ii

Cooperative Caching in Fog Radio Access Networks: A Graph-based Approach [article]

Yanxiang Jiang, Xiaoting Cui, Mehdi Bennis, Fu-Chun Zheng
2019 arXiv   pre-print
In this paper, cooperative caching is investigated in fog radio access networks (F-RAN). To maximize the offloaded traffic, cooperative caching optimization problem is formulated. By analyzing the relationship between clustering and cooperation and utilizing the solutions of the knapsack problems, the above challenging optimization problem is transformed into a clustering subproblem and a content placement subproblem. To further reduce complexity, we propose an effective graph-based approach to
more » ... solve the two subproblems. In the graph-based clustering approach, a node graph and a weighted graph are constructed. By setting the weights of the vertices of the weighted graph to be the incremental offloaded traffics of their corresponding complete subgraphs, the objective cluster sets can be readily obtained by using an effective greedy algorithm to search for the max-weight independent subset. In the graph-based content placement approach, a redundancy graph is constructed by removing the edges in the complete subgraphs of the node graph corresponding to the obtained cluster sets. Furthermore, we enhance the caching decisions to ensure each duplicate file is cached only once. Compared with traditional approximate solutions, our proposed graph-based approach has lower complexity. Simulation results show remarkable improvements in terms of offloaded traffic by using our proposed approach.
arXiv:1903.01858v1 fatcat:4daxpyqvbngghb26bx6mbmn2mq

Evolution of low mass stars: lithium problem and alpha-enhanced tracks and isochrones (Ph.D. thesis) [article]

Xiaoting Fu
2017 arXiv   pre-print
Precise studies on the Galactic bulge, halo, thick disk, and globular clusters require stellar models with alpha enhancement and various He contents. For this purpose we complement existing PARSEC (PAdova-TRieste Stellar Evolution Code) models, which are based on the solar partition, with alpha-enhanced partitions. We collect detailed measurements on the metal mixture and He abundance for the two populations of 47Tuc from literature, and calculate stellar tracks and isochrones with these
more » ... l compositions ([alpha/Fe] 0.4 and 0.2). By fitting precise CMD with HST data from low main sequence till horizontal branch, we calibrate free parameters that are important for the evolution of low mass stars. The new calibration and alpha-enhanced mixtures are applied to other metallicities. The new models reproduce the RGB bump observations much better than previous models. PARSEC is able to predict any chemical pattern in stellar evolution. Li is one of the most intriguing ones. Li abundance derived in POP II dwarfs is about three times lower than the standard Big Bang Nucleosynthesis predicts. This disagreement is referred as the cosmological lithium problem. We reconsider the stellar Li evolution from pre-main sequence to the end of main sequence by introducing the effects of convective overshooting and residual accretion. ^7Li could be significantly depleted by convective overshooting in the pre-main sequence and then partially restored in the stellar atmosphere by a tail of matter accretion which could be regulated by EUV photo-evaporation. By considering the conventional nuclear burning and microscopic diffusion along the main sequence, we reproduce the Spite plateau for m_0=0.62-0.80M_ stars, and the Li declining branch for lower mass dwarfs, with a wide range of metallicities (Z=0.00001 to Z=0.0005), starting from the primordial abundance A(Li)=2.72.
arXiv:1702.02932v1 fatcat:lahygcotjfg2vp3kneiabo7dyq

Why Poverty Impedes Decision Performance? Three Psychological Explanations

Xiaokang LV, Xinjian WANG, Xiaoting FU
2014 Advances in Psychological Science  
doi:10.3724/sp.j.1042.2014.01823 fatcat:hfiboeqmnnap7lp4dj26hd6awa

A scale-dependent finite difference method for time fractional derivative relaxation type equations [article]

XiaoTing Liu, HongGuang Sun, Yong Zhang, Zhuojia Fu
2017 arXiv   pre-print
Fractional derivative relaxation type equations (FREs) including fractional diffusion equation and fractional relaxation equation, have been widely used to describe anomalous phenomena in physics. To utilize the characteristics of fractional dynamic systems, this paper proposes a scale-dependent finite difference method (S-FDM) in which the non-uniform mesh depends on the time fractional derivative order of FRE. The purpose is to establish a stable numerical method with low computation cost for
more » ... FREs by making a bridge between the fractional derivative order and space-time discretization steps. The proposed method is proved to be unconditional stable with (2-α)-th convergence rate. Moreover, three examples are carried out to make a comparison among the uniform difference method, common non-uniform method and S-FDM in term of accuracy, convergence rate and computational costs. It has been confirmed that the S-FDM method owns obvious advantages in computational efficiency compared with uniform mesh method, especially for long-time range computation (e.g. the CPU time of S-FDM is 1/400 of uniform mesh method with better relative error for time T=500 and fractional derivative order alpha=0.4).
arXiv:1711.06450v1 fatcat:6qjvnweex5ctlkqzjkaqx6f54u

Application of optical illusion in stomatological aesthetics

ZHAO Weijia, ZHANG Pengfei, JIN Xiaoting, JIN Xiaogang, FU Baiping
2022 口腔疾病防治  
Jin XG, Fu BP reviewed the article. All authors read and approved the final manuscript as submitted. 【Competing interests】 The authors declare no competing interests.  ... 
doi:10.12016/j.issn.2096-1456.2022.02.009 doaj:58c31c415dda4ac9b611f5090a158000 fatcat:vxsisy5olvcqraexmkwnjh2njy

Nonhuman primate models of focal cerebral ischemia

Shasha Li, Jingjing Fan, Yi Li, Xinyu Fu, Lijuan Li, Xiaoting Hao
2017 Neural Regeneration Research  
Rodents have been widely used in the production of cerebral ischemia models. However, successful therapies have been proven on experimental rodent stroke model, and they have often failed to be effective when tested clinically. Therefore, nonhuman primates were recommended as the ideal alternatives, owing to their similarities with the human cerebrovascular system, brain metabolism, grey to white matter ratio and even their rich behavioral repertoire. The present review is a thorough summary of
more » ... ten methods that establish nonhuman primate models of focal cerebral ischemia; electrocoagulation, endothelin-1-induced occlusion, microvascular clip occlusion, autologous blood clot embolization, balloon inflation, microcatheter embolization, coil embolization, surgical suture embolization, suture, and photochemical induction methods. This review addresses the advantages and disadvantages of each method, as well as precautions for each model, compared nonhuman primates with rodents, different species of nonhuman primates and different modeling methods. Finally it discusses various factors that need to be considered when modelling and the method of evaluation after modelling. These are critical for understanding their respective strengths and weaknesses and underlie the selection of the optimum model.
doi:10.4103/1673-5374.200815 pmid:28400817 pmcid:PMC5361519 fatcat:lt6d2anxefci3mxrmsq53xcwai

Lithium evolution in metal-poor stars: from Pre-Main Sequence to the Spite plateau [article]

Xiaoting Fu, Alessandro Bressan, Paolo Molaro, Paola Marigo
2015 arXiv   pre-print
Fu. thanks Zhi-yu Zhang for helpful discussions. A. Bressan acknowledges PRIN INAF 2014 "Star formation and evolution in galactic nuclei". P.  ... 
arXiv:1506.05993v1 fatcat:vmlxfdbyszfinkbnrr3ben4amu

A variable-order fractal derivative model for anomalous diffusion

Xiaoting Liu, Hong-Guang Sun, Mihailo Lazarevic, Zhuojia Fu
2017 Thermal Science  
This paper pays attention to develop a variable-order fractal derivative model for anomalous diffusion. Previous investigations have indicated that the medium structure, fractal dimension or porosity may change with time or space during solute transport processes, results in time or spatial dependent anomalous diffusion phenomena. Hereby, this study makes an attempt to introduce a variable-order fractal derivative diffusion model, in which the index of fractal derivative depends on temporal
more » ... nt or spatial position, to characterize the previous mentioned anomalous diffusion (or transport) processes. Compared with other models, the main advantages in description and the physical explanation of new model are explored by numerical simulation. Further discussions on the dissimilitude such as computational efficiency, diffusion behavior, and heavy tail phenomena of the new model, and variable-order fractional derivative model are also offered.
doi:10.2298/tsci160415244l fatcat:4lxlsd5kdjdodnno6d3wppcbbi

Rapid identification and characterization of genetic loci for defective kernel in bread wheat

Chao Fu, Jiuyuan Du, Xiuling Tian, Zhonghu He, Luping Fu, Yue Wang, Dengan Xu, Xiaoting Xu, Xianchun Xia, Yan Zhang, Shuanghe Cao
2019 BMC Plant Biology  
Wheat is a momentous crop and feeds billions of people in the world. The improvement of wheat yield is very important to ensure world food security. Normal development of grain is the essential guarantee for wheat yield formation. The genetic study of grain phenotype and identification of key genes for grain filling are of great significance upon dissecting the molecular mechanism of wheat grain morphogenesis and yield potential. Here we identified a pair of defective kernel (Dek) isogenic
more » ... , BL31 and BL33, with plump and shrunken mature grains, respectively, and constructed a genetic population from the BL31/BL33 cross. Ten chromosomes had higher frequency of polymorphic single nucleotide polymorphism (SNP) markers between BL31 and BL33 using Wheat660K chip. Totally 783 simple sequence repeat (SSR) markers were chosen from the above chromosomes and 15 of these were integrated into two linkage groups using the genetic population. Genetic mapping identified three QTL, QDek.caas-3BS.1, QDek.caas-3BS.2 and QDek.caas-4AL, explaining 14.78-18.17%, 16.61-21.83% and 19.08-28.19% of phenotypic variances, respectively. Additionally, five polymorphic SNPs from Wheat660K were successfully converted into cleaved amplified polymorphic sequence (CAPS) markers and enriched the target regions of the above QTL. Biochemical analyses revealed that BL33 has significantly higher grain sucrose contents at filling stages and lower mature grain starch contents than BL31, indicating that the Dek QTL may be involved in carbohydrate metabolism. As such, the candidate genes for each QTL were predicated according to International Wheat Genome Sequence Consortium (IWGSC) RefSeq v1.0. Three major QTL for Dek were identified and their causal genes were predicted, laying a foundation to conduct fine mapping and dissect the regulatory mechanism underlying Dek trait in wheat.
doi:10.1186/s12870-019-2102-6 pmid:31703630 pmcid:PMC6842267 fatcat:eozmz2l7jffi3ddcud7foeag3i

Pervaporation of phenol wastewater with PVDF–PU blend membrane

Yanhui Wu, Guangqin Tian, Huifen Tan, Xiaoting Fu
2013 Desalination and Water Treatment  
A B S T R A C T The compatibility of poly (vinylidene fluoride) (PVDF) and polyurethane (PU) was studied based on the theoretical analysis of solubility parameter and mixing enthalpy. The results showed that PVDF and PU are partially compatible. Then, the blend membranes of PVDF-PU with 5, 10, and 80 wt.% PVDF content were prepared with the application of solution blending in solvent N, N-dimethylacetamide (DMA). The membranes were characterized by Fourier transformed infrared spectroscopy
more » ... R) to assess the intermolecular interactions. And the morphology of the membranes was studied by scanning electron microscope (SEM). 80wt.% PVDF-PU membrane was porous. However, 5% and 10% PVDF-PU membrane were suitable for pervaporation. The study showed that the degree of swelling (DS) of PVDF-PU membrane increased with the phenol concentration, which suggested that these membranes have stronger sorption capacity to phenol. Then, the pervapration performance of the membranes was examined. The results showed that the pevaporation performances of the blend membranes have been improved comparing with the plain PU membrane.
doi:10.1080/19443994.2013.768789 fatcat:a4io75wdbbbuber4bgnye6gmna

Rheological Properties of Five Plant Gums

Quanquan Miao, Huaishi Jiang, Lei Gao, Yujie Cheng, Jiachao Xu, Xiaoting Fu, Xin Gao
2018 American Journal of Analytical Chemistry  
The rheological properties of five gum solutions (Gum Shiraz, Karaya Gum, Ghatti Gum, Arabic Gum and Gum Tragacanth) have been examined. The five mucilage solutions exhibited non-Newtonian, shear-thinning with thixotropy at higher concentrations (0.5% -1%, m/v). According to the change of viscosity with increasing temperature, all five gums could be defined as three types: gum tragacanth and gum shiraz have a good temperature stability; karaya gum is affected by temperature obviously; the
more » ... ing two gums have a general stability. The viscosity of mucilage solutions (Arabic Gum, Ghatti Gum and Karaya Gum) had an apparent dependence on temperature. The parameter n of Shiraz Gum is the minimum, which means it has the best flow properties. The flow activation energy of karaya gum is 2.683 kcal which is the highest than other gums so that it has a great influence on temperature. The gum solutions' viscosity had different sensitive degree over tested pH range (pH 2 -10). Shiraz gum and arabic gum possessed better acid-proof and alkali-proof respectively. The addition of salts (NaCl and CaCl 2 ) led to the reduction of viscosity, which was more sensitive to Ca 2+ than to Na + . Both storage modulus G' and loss modulus G" of all five gums had a dependence on temperature and frequency. These results are potentially useful for the application in the field of food processing.
doi:10.4236/ajac.2018.94017 fatcat:5mrmi23ehzednjvfoqfa3cvvyi

Molecular surveillance of HIV, HBV, and HCV amongst blood donors in five Chinese regions [article]

Xiaoting Lv, Mary A Rodgers, Peng Yin, Ling Ke, Ping Fu, Binting Wu, Yu Liu
2020 bioRxiv   pre-print
Surveillance of the variance of those viruses is an important way to monitor their diversity and evolution to improve safety in blood transfusion. In this study, we characterized the specimens of blood donors from 13 blood centers located in 5 Chinese regions. Samples collected between 2014 and 2017 were included in the study and were screened with serological and molecular tests. Sequencing was used to determine the classifications of HIV, HBV, or HCV. The HBV immune escape mutations were also
more » ... analyzed for assessing vaccine breakthrough risks and challenges for diagnostic tests. For HIV, 107 out of 215 positive samples were sequenced, and 11 genotypes or recombinants were identified. The predominant genotype was C, which accounts for 42%. For HBV, 113 out of 207 positive samples were sequenced. The genotypes of B, C and D were identified, with B and C predominating. The major subgenotype was B2, comprising 84.1% of all infections. 79 out of 113 (69.9%) samples carried escape mutations in the "a" determinant region with 69 (87.3%) multiple mutants and 15 (19%) escape mutants which will affect HBsAg detection. For HCV, 60 out of 203 HCV samples were sequenced, and 7 genotypes or subtypes were identified. The major genotype was 1b (48%), followed by 6a (16.7%) and 2a & 3a (10%).
doi:10.1101/2020.01.22.916320 fatcat:nsmg3fhzrnhk3fvt2xdwfvp5wq
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