Assembly processes of prokaryotic and microeukaryotic community is an important issue in microbial ecology.However,unclear remains about the relative contribution of deterministic and stochastic processes to the shapi...Assembly processes of prokaryotic and microeukaryotic community is an important issue in microbial ecology.However,unclear remains about the relative contribution of deterministic and stochastic processes to the shaping of prokaryotic and microeukaryotic communities in saline lake water.Here,we systematically investigated the assembly processes governing the prokaryotic and microeukaryotic communities in Qinghai Lake with the use of Illumina sequencing and a null model.The results showed that both deterministic and stochastic processes play vital roles in shaping the assemblies of prokaryotic and microeukaryotic communities,in which stochastic processes appeared to dominate(> 70%).Prokaryotic communities were mainly governed by non-dominant processes(60.4%),followed by homogeneous selection(15.8%),variable selection(13.6%) and dispersal limitation(10.2%),whereas microeukaryotes were strongly driven by non-dominant processes(68.9%),followed by variable selection(23.6%) and homogenizing dispersal(6.3%).In terms of variable selection,nutrients(e.g.,ammonium,dissolved inorganic carbon,dissolved organic carbon and total nitrogen) were the major factors influencing prokaryotic and microeukaryotic community structures.In summary,prokaryotes and microeukaryotes can be predominantly structured by different assembly mechanisms,in which stochasticity is stronger than deterministic processes.This finding helps to better comprehend the assembly of prokaryotic and eukaryotic communities in saline lakes.展开更多
Millimetre-wave(mmWave)technology continues to draw great interest due to its broad applications in wireless communications,radar,and spectroscopy.Compared to pure electronic solutions,photonic-based mmWave generation...Millimetre-wave(mmWave)technology continues to draw great interest due to its broad applications in wireless communications,radar,and spectroscopy.Compared to pure electronic solutions,photonic-based mmWave generation provides wide bandwidth,low power dissipation,and remoting through low-loss fibres.However,at high frequencies,two major challenges exist for the photonic system:the power roll-off of the photodiode,and the large signal linewidth derived directly from the lasers.Here,we demonstrate a new photonic mmWave platform combining integrated microresonator solitons and high-speed photodiodes to address the challenges in both power and coherence.The solitons,being inherently mode-locked,are measured to provide 5.8 dB additional gain through constructive interference among mmWave beatnotes,and the absolute mmWave power approaches the theoretical limit of conventional heterodyne detection at 100 GHz.In our free-running system,the soliton is capable of reducing the mmWave linewidth by two orders of magnitude from that of the pump laser.Our work leverages microresonator solitons and high-speed modified uni-traveling carrier photodiodes to provide a viable path to chip-scale,high-power,low-noise,high-frequency sources for mmWave applications.展开更多
Radio-frequency(RF) waveform synthesis has broad applications in ultrawide-bandwidth wireless communications, radar systems, and electronic testing. Photonic-based approaches offer key advantages in bandwidth and phas...Radio-frequency(RF) waveform synthesis has broad applications in ultrawide-bandwidth wireless communications, radar systems, and electronic testing. Photonic-based approaches offer key advantages in bandwidth and phase noise thanks to the ultrahigh optical carrier frequency. In this work, we demonstrate Fourier synthesis arbitrary waveform generation(AWG) with integrated optical microresonator solitons. The RF temporal waveform is synthesized through line-by-line amplitude and phase shaping of an optical soliton microcomb, which is down-converted to the RF domain through dual-comb optical coherent sampling. A variety of RF waveforms with tunable repetition cycles are shown in our demonstration. Our approach provides not only the possibility of precise Fourier synthesis at microwave and millimeter-wave frequencies, but also a viable path to fully integrated photonic-based RF AWG on a chip.展开更多
Runt-related transcription factor 1(RUNX1)is an essential regulator of normal hematopoiesis.Its dysfunction,caused by either fusions or mutations,is frequently reported in acute myeloid leukemia(AML).However,RUNX1 mut...Runt-related transcription factor 1(RUNX1)is an essential regulator of normal hematopoiesis.Its dysfunction,caused by either fusions or mutations,is frequently reported in acute myeloid leukemia(AML).However,RUNX1 mutations have been largely under-explored compared with RUNX1 fusions mainly due to their elusive genetic characteristics.Here,based on 1741 patients with AML,we report a unique expression pattern associated with RUNX1 mutations in AML.This expression pattern was coordinated by target repression and promoter hypermethylation.We first reanalyzed a joint AML cohort that consisted of three public cohorts and found that RUNX1 mutations were mainly distributed in the Runt domain and almost mutually exclusive with NPM1 mutations.Then,based on RNA-seq data from The Cancer Genome Atlas AML cohort,we developed a 300-gene signature that significantly distinguished the patients with RUNX1 mutations from those with other AML subtypes.Furthermore,we explored the mechanisms underlying this signature from the transcriptional and epigenetic levels.Using chromatin immunoprecipitation sequencing data,we found that RUNX1 target genes tended to be repressed in patients with RUNX1 mutations.Through the integration of DNA methylation array data,we illustrated that hypermethylation on the promoter regions of RUNX1-regulated genes also contributed to dysregulation in RUNX1-mutated AML.This study revealed the distinct gene expression pattern of RUNX1 mutations and the underlying mechanisms in AML development.展开更多
基金supported by grants from the National Natural Science Foundation of China (Nos.92251304 and 41972317)the 111 Program (State Administration of Foreign Experts Affairs&the Ministry of Education of China,No.B18049)+2 种基金the Second Tibetan Plateau Scientific Expedition and Research Program (STEP)(No.2019QZKK0805)the Science and Technology Plan Project of Qinghai Province (No.2022-ZJ-Y08)State Key Laboratory of Biogeology and Environmental Geology,CUG (No.GBL11805)。
文摘Assembly processes of prokaryotic and microeukaryotic community is an important issue in microbial ecology.However,unclear remains about the relative contribution of deterministic and stochastic processes to the shaping of prokaryotic and microeukaryotic communities in saline lake water.Here,we systematically investigated the assembly processes governing the prokaryotic and microeukaryotic communities in Qinghai Lake with the use of Illumina sequencing and a null model.The results showed that both deterministic and stochastic processes play vital roles in shaping the assemblies of prokaryotic and microeukaryotic communities,in which stochastic processes appeared to dominate(> 70%).Prokaryotic communities were mainly governed by non-dominant processes(60.4%),followed by homogeneous selection(15.8%),variable selection(13.6%) and dispersal limitation(10.2%),whereas microeukaryotes were strongly driven by non-dominant processes(68.9%),followed by variable selection(23.6%) and homogenizing dispersal(6.3%).In terms of variable selection,nutrients(e.g.,ammonium,dissolved inorganic carbon,dissolved organic carbon and total nitrogen) were the major factors influencing prokaryotic and microeukaryotic community structures.In summary,prokaryotes and microeukaryotes can be predominantly structured by different assembly mechanisms,in which stochasticity is stronger than deterministic processes.This finding helps to better comprehend the assembly of prokaryotic and eukaryotic communities in saline lakes.
基金The authors thank Ligentec and VLC Photonics for resonator fabrication,S.Bowers at UVA for access to the spearum analyser,and Q.F.Yang at Caltech for helpful comments during the preparation of this manuscript.The authors also gratefully acknowledge the support from the National Science Foundation and Defense Advanced Research Projeas Agency(DARPA)under HR0011-ISC-0055(DODOS).X.Y.is also supported by Virginia Space Grant Consortium.
文摘Millimetre-wave(mmWave)technology continues to draw great interest due to its broad applications in wireless communications,radar,and spectroscopy.Compared to pure electronic solutions,photonic-based mmWave generation provides wide bandwidth,low power dissipation,and remoting through low-loss fibres.However,at high frequencies,two major challenges exist for the photonic system:the power roll-off of the photodiode,and the large signal linewidth derived directly from the lasers.Here,we demonstrate a new photonic mmWave platform combining integrated microresonator solitons and high-speed photodiodes to address the challenges in both power and coherence.The solitons,being inherently mode-locked,are measured to provide 5.8 dB additional gain through constructive interference among mmWave beatnotes,and the absolute mmWave power approaches the theoretical limit of conventional heterodyne detection at 100 GHz.In our free-running system,the soliton is capable of reducing the mmWave linewidth by two orders of magnitude from that of the pump laser.Our work leverages microresonator solitons and high-speed modified uni-traveling carrier photodiodes to provide a viable path to chip-scale,high-power,low-noise,high-frequency sources for mmWave applications.
文摘Radio-frequency(RF) waveform synthesis has broad applications in ultrawide-bandwidth wireless communications, radar systems, and electronic testing. Photonic-based approaches offer key advantages in bandwidth and phase noise thanks to the ultrahigh optical carrier frequency. In this work, we demonstrate Fourier synthesis arbitrary waveform generation(AWG) with integrated optical microresonator solitons. The RF temporal waveform is synthesized through line-by-line amplitude and phase shaping of an optical soliton microcomb, which is down-converted to the RF domain through dual-comb optical coherent sampling. A variety of RF waveforms with tunable repetition cycles are shown in our demonstration. Our approach provides not only the possibility of precise Fourier synthesis at microwave and millimeter-wave frequencies, but also a viable path to fully integrated photonic-based RF AWG on a chip.
基金supported in part by the National Natural Science Foundation of China(Nos.81890994,81770153,81530003,and 81911530240)the National Key Research and Development Program of China(No.2019YFA0905900).
文摘Runt-related transcription factor 1(RUNX1)is an essential regulator of normal hematopoiesis.Its dysfunction,caused by either fusions or mutations,is frequently reported in acute myeloid leukemia(AML).However,RUNX1 mutations have been largely under-explored compared with RUNX1 fusions mainly due to their elusive genetic characteristics.Here,based on 1741 patients with AML,we report a unique expression pattern associated with RUNX1 mutations in AML.This expression pattern was coordinated by target repression and promoter hypermethylation.We first reanalyzed a joint AML cohort that consisted of three public cohorts and found that RUNX1 mutations were mainly distributed in the Runt domain and almost mutually exclusive with NPM1 mutations.Then,based on RNA-seq data from The Cancer Genome Atlas AML cohort,we developed a 300-gene signature that significantly distinguished the patients with RUNX1 mutations from those with other AML subtypes.Furthermore,we explored the mechanisms underlying this signature from the transcriptional and epigenetic levels.Using chromatin immunoprecipitation sequencing data,we found that RUNX1 target genes tended to be repressed in patients with RUNX1 mutations.Through the integration of DNA methylation array data,we illustrated that hypermethylation on the promoter regions of RUNX1-regulated genes also contributed to dysregulation in RUNX1-mutated AML.This study revealed the distinct gene expression pattern of RUNX1 mutations and the underlying mechanisms in AML development.
