A silicon-based germanium(Ge)photodetector working for C and L bands is proposed in this paper.The device fea-tures a novel asymmetric PIN structure,which contributes to a more optimized electric field distribution in...A silicon-based germanium(Ge)photodetector working for C and L bands is proposed in this paper.The device fea-tures a novel asymmetric PIN structure,which contributes to a more optimized electric field distribution in Ge and a shorter effective width of depleted region.Meanwhile,the optical structure is designed carefully to enhance responsivity for broad-band.Under-7 V,where the weak avalanche process happens,the responsivity of our device is 1.49 and 1.16 A/W at 1550 and 1600 nm,with bandwidth of 47.1 and 44.5 GHz,respectively.These performances demonstrate the significant application poten-tial of the device in optical communication systems.展开更多
Nucleotide-binding and oligomerization domain 2(NOD2),a member of the NOD protein family,plays an important role in innate immunity.In response to pathogen attack,NOD2 stimulates cytokine and defensin production by ac...Nucleotide-binding and oligomerization domain 2(NOD2),a member of the NOD protein family,plays an important role in innate immunity.In response to pathogen attack,NOD2 stimulates cytokine and defensin production by activating nuclear factor(NF)-kB,a key transcription factor responsible for mediating downstream reactions.However,the mechanism linking NOD2 regulation and NF-kB activation is poorly understood.Using bioinformatics,we found a completely preserved canonical NF-kB binding site in the NOD2 core promoter(216 to 225 bp)in both humans and chimpanzees.The functional role of this NF-kB binding site was investigated using the enhanced green fluorescent protein(EGFP)reporter system,site-directed mutagenesis,the NF-kB activation inhibitor(JSH-23)and the chromatin immunoprecipitation(ChIP)assay.The results show that the NF-kB binding site is critical for regulation of the NOD2 gene.Either deletion of the NF-kB binding elements within the NOD2 promoter or treatment with an NF-kB activation inhibitor could lead to a significant loss of NOD2 promoter activity as detected by reporter gene assay.The canonical NF-kB binding site was bound by NF-kB as determined by the ChIP method.Based on these results,we suggest a positive feedback regulation between NF-kB and NOD2,which may represent an efficient mechanism in response to pathogen invasion.展开更多
The care of obstetrics patients has improved dramatically over the past few decades.Unfortunately,rates of cesarean section remain high,and decreasing this rate requires close care and follow-up in the prenatal outpat...The care of obstetrics patients has improved dramatically over the past few decades.Unfortunately,rates of cesarean section remain high,and decreasing this rate requires close care and follow-up in the prenatal outpatient setting.Counseling regarding cesarean delivery and vaginal delivery is imperative.Opportunities still exist in helping patients objectively weigh the decision for cesarean delivery versus vaginal delivery.Additional developments have occurred in the intrapartum and the postpartum setting,with an aim to improve patient and neonatal outcomes.Changes have been implemented for patients undergoing cesarean delivery including preoperative and intraoperative treatment of pain,nausea,and vomiting,as well as postoperative care bundles that improve patient outcomes.Innovations have also occurred in the care of postpartum patients after vaginal delivery,again with improvements in patient outcomes.This article summarizes the current evidence,provides care recommendations,and identifies the next steps in improving obstetrics care.展开更多
The 2μm wavelength band emerges as a promising candidate for the next communication window to enhance the transmission capacity of data.A high-responsivity and high-speed photodetector operating at 2μm is crucial fo...The 2μm wavelength band emerges as a promising candidate for the next communication window to enhance the transmission capacity of data.A high-responsivity and high-speed photodetector operating at 2μm is crucial for the 2-μm-wavelength-band communication system.Here,we present an on-chip waveguide-coupled germanium photodetector with remarkably high responsivity and data-receiving rate,employing subbandgap light absorption and avalanche multiplication.The device is designed with an ingenious and simple asymmetric lateral p-i-n junction structure and fabricated through a standard CMOS process by a commercial factory.It has a responsivity of 3.64 A/W and a maximum bandwidth of 50 GHz at 2μm wavelength.For the first time,to the best of our knowledge,an optical receiving rate of up to 112 Gbps is demonstrated at 2μm,verifying its feasibility in a highspeed 2-μm-band communication system.To the best of our knowledge,the proposed device stands out as the fastest photodiode with the highest responsivity among all group III-V and group IV photodetectors working in the 2μm wavelength band.展开更多
基金supported by National Key Research and Development Program of China(2022YFB2802400)National Natural Science Foundation of China(62250010,62090054,62274160)Youth Innovation Promotion Association of the Chinese Academy of Sciences(2021111).
文摘A silicon-based germanium(Ge)photodetector working for C and L bands is proposed in this paper.The device fea-tures a novel asymmetric PIN structure,which contributes to a more optimized electric field distribution in Ge and a shorter effective width of depleted region.Meanwhile,the optical structure is designed carefully to enhance responsivity for broad-band.Under-7 V,where the weak avalanche process happens,the responsivity of our device is 1.49 and 1.16 A/W at 1550 and 1600 nm,with bandwidth of 47.1 and 44.5 GHz,respectively.These performances demonstrate the significant application poten-tial of the device in optical communication systems.
基金supported by grants from the Natural Science Foundation of Guangdong Province(No.06025159)the Natural Science Foundation from Department of Education of Guangdong Province(No.126(2005)).
文摘Nucleotide-binding and oligomerization domain 2(NOD2),a member of the NOD protein family,plays an important role in innate immunity.In response to pathogen attack,NOD2 stimulates cytokine and defensin production by activating nuclear factor(NF)-kB,a key transcription factor responsible for mediating downstream reactions.However,the mechanism linking NOD2 regulation and NF-kB activation is poorly understood.Using bioinformatics,we found a completely preserved canonical NF-kB binding site in the NOD2 core promoter(216 to 225 bp)in both humans and chimpanzees.The functional role of this NF-kB binding site was investigated using the enhanced green fluorescent protein(EGFP)reporter system,site-directed mutagenesis,the NF-kB activation inhibitor(JSH-23)and the chromatin immunoprecipitation(ChIP)assay.The results show that the NF-kB binding site is critical for regulation of the NOD2 gene.Either deletion of the NF-kB binding elements within the NOD2 promoter or treatment with an NF-kB activation inhibitor could lead to a significant loss of NOD2 promoter activity as detected by reporter gene assay.The canonical NF-kB binding site was bound by NF-kB as determined by the ChIP method.Based on these results,we suggest a positive feedback regulation between NF-kB and NOD2,which may represent an efficient mechanism in response to pathogen invasion.
文摘The care of obstetrics patients has improved dramatically over the past few decades.Unfortunately,rates of cesarean section remain high,and decreasing this rate requires close care and follow-up in the prenatal outpatient setting.Counseling regarding cesarean delivery and vaginal delivery is imperative.Opportunities still exist in helping patients objectively weigh the decision for cesarean delivery versus vaginal delivery.Additional developments have occurred in the intrapartum and the postpartum setting,with an aim to improve patient and neonatal outcomes.Changes have been implemented for patients undergoing cesarean delivery including preoperative and intraoperative treatment of pain,nausea,and vomiting,as well as postoperative care bundles that improve patient outcomes.Innovations have also occurred in the care of postpartum patients after vaginal delivery,again with improvements in patient outcomes.This article summarizes the current evidence,provides care recommendations,and identifies the next steps in improving obstetrics care.
基金National Key Research and Development Program of China(2022YFB2803100)National Natural Science Foundation of China(62090054,62250010,62274160)+2 种基金Youth Innovation Promotion Association of the Chinese Academy of Sciences(2021111)Strategic Leading Science and Technology Project,CAS(XDB43020100)China Computer Interconnect Technology Alliance(CCITA)Funding(20240104)。
文摘The 2μm wavelength band emerges as a promising candidate for the next communication window to enhance the transmission capacity of data.A high-responsivity and high-speed photodetector operating at 2μm is crucial for the 2-μm-wavelength-band communication system.Here,we present an on-chip waveguide-coupled germanium photodetector with remarkably high responsivity and data-receiving rate,employing subbandgap light absorption and avalanche multiplication.The device is designed with an ingenious and simple asymmetric lateral p-i-n junction structure and fabricated through a standard CMOS process by a commercial factory.It has a responsivity of 3.64 A/W and a maximum bandwidth of 50 GHz at 2μm wavelength.For the first time,to the best of our knowledge,an optical receiving rate of up to 112 Gbps is demonstrated at 2μm,verifying its feasibility in a highspeed 2-μm-band communication system.To the best of our knowledge,the proposed device stands out as the fastest photodiode with the highest responsivity among all group III-V and group IV photodetectors working in the 2μm wavelength band.
