In this paper,a systematic description of the artificial intelligence(AI)-based channel estimation track of the 2nd Wireless Communication AI Competition(WAIC)is provided,which is hosted by IMT-2020(5G)Promotion Group...In this paper,a systematic description of the artificial intelligence(AI)-based channel estimation track of the 2nd Wireless Communication AI Competition(WAIC)is provided,which is hosted by IMT-2020(5G)Promotion Group 5G+AIWork Group.Firstly,the system model of demodulation reference signal(DMRS)based channel estimation problem and its corresponding dataset are introduced.Then the potential approaches for enhancing the performance of AI based channel estimation are discussed from the viewpoints of data analysis,pre-processing,key components and backbone network structures.At last,the final competition results composed of different solutions are concluded.It is expected that the AI-based channel estimation track of the 2nd WAIC could provide insightful guidance for both the academia and industry.展开更多
The use of two inhibitors of Mek1/2 and Gsk3β(2i)promotes the generation of mouse diploid and haploid embryonic stem cells(ESCs)from the inner cell mass of biparental and uniparental blastocysts,respectively.However,...The use of two inhibitors of Mek1/2 and Gsk3β(2i)promotes the generation of mouse diploid and haploid embryonic stem cells(ESCs)from the inner cell mass of biparental and uniparental blastocysts,respectively.However,a system enabling long-term maintenance of imprints in ESCs has proven challenging.Here,we report that the use of a two-step a2i(alternative two inhibitors of Src and Gsk3β,TSa2i)derivation/culture protocol results in the establishment of androgenetic haploid ESCs(AG-haESCs)with stable DNA methylation at paternal DMRs(differentially DNA methylated regions)up to passage 60 that can efficiently support generating mice upon oocyte injection.We also show coexistence of H3K9me3 marks and ZFP57 bindings with intact DMR methylations.Furthermore,we demonstrate that TSa2itreated AG-haESCs are a heterogeneous cell population regarding paternal DMR methylation.Strikingly,AGhaESCs with late passages display increased paternal-DMR methylations and improved developmental potential compared to early-passage cells,in part through the enhanced proliferation of H19-DMR hypermethylated cells.Together,we establish AG-haESCs that can longterm maintain paternal imprints.展开更多
LTE-A下行传输通信系统中采用了多达8天线端口的增强型MIMO技术,引入了新的参考信号DMRS,用于MIMO下行信道估计。分析LTE-A系统中基于DMRS的信道估计算法,提出了一种低复杂度的频域线性最小均方误差(LMMSE)插值算法。该算法基于DMRS对...LTE-A下行传输通信系统中采用了多达8天线端口的增强型MIMO技术,引入了新的参考信号DMRS,用于MIMO下行信道估计。分析LTE-A系统中基于DMRS的信道估计算法,提出了一种低复杂度的频域线性最小均方误差(LMMSE)插值算法。该算法基于DMRS对信道时延参数进行估计,并采用Look Up Table(LUT)方式,选择相应的频域插值矩阵,完成频域LMMSE插值过程。它解决了传统频域LMMSE算法中获取信道二阶统计信息的困难,也避免了对矩阵的实时求逆过程。仿真结果表明,此方法在降低了复杂度的同时保证了BER和MSE的性能,具有较大的实用性。展开更多
An association between assisted reproductive technology （ART） and neurobehavioral imprinting disorders has been reported in many studies, and it seems that ART may interfere with imprint reprogramming. However, it h...An association between assisted reproductive technology （ART） and neurobehavioral imprinting disorders has been reported in many studies, and it seems that ART may interfere with imprint reprogramming. However, it has never been explored whether epigenetic erros or imprinting disease susceptibility induced by ART can be inherited transgenerationally. Hence, the aim of this study was to determine the effect of in vitro fertilization and embryo transfer （IVF-ET） on transgenerational inheritance in am inbred mouse model. Mice derived from IVF-ET were outcrossed to wild-type C57BL/6J to obtain their female and male line F2 and F3 generations. Their behavior, morphology, histology, and DNA methylation status at several important differentially methylated regions （DMRs） were analyzed by Morris water maze, hematoxylin and eosin （H＆E） staining, and bisulfite genomic sequencing. No significant differences in spatial learning or phenotypic abnormality were found in adults derived from IVF （F1） and female and male line F2 and F3 generations. A borderline trend of hypomethylation was found in H19 DMR CpG island 3 in the female line-derived F3 generation （0.40±0.118, P=0.086）. Methylation status in H19/Igf2 DMR island 1, Igf2 DMR, KvDMR, and Snrpn DMR displayed normal patterns. Methylation percentage did not differ significantly from that of adults conceived naturally, and the expression of the genes they regulated was not disturbed. Transgenerational integrity, such as behavior, morphology, histology, and DNA methylation status, was maintained in these generations, which indicates that exposure of female germ cells to hormonel stimulation and gamete manipulation might not affect the individuals and their descendents.展开更多
文摘In this paper,a systematic description of the artificial intelligence(AI)-based channel estimation track of the 2nd Wireless Communication AI Competition(WAIC)is provided,which is hosted by IMT-2020(5G)Promotion Group 5G+AIWork Group.Firstly,the system model of demodulation reference signal(DMRS)based channel estimation problem and its corresponding dataset are introduced.Then the potential approaches for enhancing the performance of AI based channel estimation are discussed from the viewpoints of data analysis,pre-processing,key components and backbone network structures.At last,the final competition results composed of different solutions are concluded.It is expected that the AI-based channel estimation track of the 2nd WAIC could provide insightful guidance for both the academia and industry.
基金This study was supported by Genome Tagging Project and grants from the Chinese Academy of Sciences,the National Key Research and Development Program of Chinathe National Natural Science Foundation of China(2019YFA0109900,2020YFA0509000,XDB19010204,QYZDJ-SSW-SMC023,Facility-based Open Research Program,31821004,32030029,and 31730062).
文摘The use of two inhibitors of Mek1/2 and Gsk3β(2i)promotes the generation of mouse diploid and haploid embryonic stem cells(ESCs)from the inner cell mass of biparental and uniparental blastocysts,respectively.However,a system enabling long-term maintenance of imprints in ESCs has proven challenging.Here,we report that the use of a two-step a2i(alternative two inhibitors of Src and Gsk3β,TSa2i)derivation/culture protocol results in the establishment of androgenetic haploid ESCs(AG-haESCs)with stable DNA methylation at paternal DMRs(differentially DNA methylated regions)up to passage 60 that can efficiently support generating mice upon oocyte injection.We also show coexistence of H3K9me3 marks and ZFP57 bindings with intact DMR methylations.Furthermore,we demonstrate that TSa2itreated AG-haESCs are a heterogeneous cell population regarding paternal DMR methylation.Strikingly,AGhaESCs with late passages display increased paternal-DMR methylations and improved developmental potential compared to early-passage cells,in part through the enhanced proliferation of H19-DMR hypermethylated cells.Together,we establish AG-haESCs that can longterm maintain paternal imprints.
文摘LTE-A下行传输通信系统中采用了多达8天线端口的增强型MIMO技术,引入了新的参考信号DMRS,用于MIMO下行信道估计。分析LTE-A系统中基于DMRS的信道估计算法,提出了一种低复杂度的频域线性最小均方误差(LMMSE)插值算法。该算法基于DMRS对信道时延参数进行估计,并采用Look Up Table(LUT)方式,选择相应的频域插值矩阵,完成频域LMMSE插值过程。它解决了传统频域LMMSE算法中获取信道二阶统计信息的困难,也避免了对矩阵的实时求逆过程。仿真结果表明,此方法在降低了复杂度的同时保证了BER和MSE的性能,具有较大的实用性。
基金supported by the National Basic Research Program (973) of China (No. 2007CB948104)the National Natural Science Foundation of China (No. 81070532)the Zhejiang Provincial Natural Science Foundation of China (No. Z207021)
文摘An association between assisted reproductive technology （ART） and neurobehavioral imprinting disorders has been reported in many studies, and it seems that ART may interfere with imprint reprogramming. However, it has never been explored whether epigenetic erros or imprinting disease susceptibility induced by ART can be inherited transgenerationally. Hence, the aim of this study was to determine the effect of in vitro fertilization and embryo transfer （IVF-ET） on transgenerational inheritance in am inbred mouse model. Mice derived from IVF-ET were outcrossed to wild-type C57BL/6J to obtain their female and male line F2 and F3 generations. Their behavior, morphology, histology, and DNA methylation status at several important differentially methylated regions （DMRs） were analyzed by Morris water maze, hematoxylin and eosin （H＆E） staining, and bisulfite genomic sequencing. No significant differences in spatial learning or phenotypic abnormality were found in adults derived from IVF （F1） and female and male line F2 and F3 generations. A borderline trend of hypomethylation was found in H19 DMR CpG island 3 in the female line-derived F3 generation （0.40±0.118, P=0.086）. Methylation status in H19/Igf2 DMR island 1, Igf2 DMR, KvDMR, and Snrpn DMR displayed normal patterns. Methylation percentage did not differ significantly from that of adults conceived naturally, and the expression of the genes they regulated was not disturbed. Transgenerational integrity, such as behavior, morphology, histology, and DNA methylation status, was maintained in these generations, which indicates that exposure of female germ cells to hormonel stimulation and gamete manipulation might not affect the individuals and their descendents.
