Usually,the problem of direction-of-arrival(DOA)estimation is performed based on the assumption of uniform noise.In many applications,however,the noise across the array may be nonuniform.In this situation,the performa...Usually,the problem of direction-of-arrival(DOA)estimation is performed based on the assumption of uniform noise.In many applications,however,the noise across the array may be nonuniform.In this situation,the performance of DOA estimators may be deteriorated greatly if the non-uniformity of noise is ignored.To tackle this problem,we consider the problem of DOA es-timation in the presence of nonuniform noise by leveraging a singular value thresholding(SVT)based matrix completion method.Different from that the traditional SVT method apply fixed threshold,to improve the performance,the proposed method can obtain a more suitable threshold based on careful estimation of the signal-to-noise ratio(SNR)levels.Specifically,we firstly employ an SVT-based matrix completion method to estimate the noise-free covariance matrix.On this basis,the signal and noise subspaces are obtained from the eigendecomposition of the noise-free cov-ariance matrix.Finally,traditional subspace-based DOA estimation approaches can be directly ap-plied to determine the DOAs.Numerical simulations are performed to demonstrate the effective-ness of the proposed method.展开更多
Purpose: To understand how authors and reviewers are accepting and embracing Open Peer Review(OPR), one of the newest innovations in the Open Science movement.Design/methodology/approach: This research collected and a...Purpose: To understand how authors and reviewers are accepting and embracing Open Peer Review(OPR), one of the newest innovations in the Open Science movement.Design/methodology/approach: This research collected and analyzed data from the Open Access journal Peer J over its first three years(2013–2016). Web data were scraped, cleaned, and structured using several Web tools and programs. The structured data were imported into a relational database. Data analyses were conducted using analytical tools as well as programs developed by the researchers.Findings: Peer J, which supports optional OPR, has a broad international representation of authors and referees. Approximately 73.89% of articles provide full review histories. Of the articles with published review histories, 17.61% had identities of all reviewers and 52.57% had at least one signed reviewer. In total, 43.23% of all reviews were signed. The observed proportions of signed reviews have been relatively stable over the period since the Journal’s inception.Research limitations: This research is constrained by the availability of the peer review history data. Some peer reviews were not available when the authors opted out of publishing their review histories. The anonymity of reviewers made it impossible to give an accurate count of reviewers who contributed to the review process. Practical implications: These findings shed light on the current characteristics of OPR. Given the policy that authors are encouraged to make their articles’ review history public and referees are encouraged to sign their review reports, the three years of Peer J review data demonstrate that there is still some reluctance by authors to make their reviews public and by reviewers to identify themselves. Originality/value: This is the first study to closely examine Peer J as an example of an OPR model journal. As Open Science moves further towards open research, OPR is a final and critical component. Research in this area must identify the best policies and paths towards a transparent and open peer review process for scientific communication.展开更多
Phytocyanin(PC)is a class of plant-specific blue copper proteins involved in electron transport,plant growth,development,and stress resistance.However,PC proteins have not been systematically evaluated in tobacco plan...Phytocyanin(PC)is a class of plant-specific blue copper proteins involved in electron transport,plant growth,development,and stress resistance.However,PC proteins have not been systematically evaluated in tobacco plants.We determined the whole-genome sequences of the PC family in the tobacco cultivar‘K326.’The transcriptome data were used to analyze the expression of the NtPC family at different development stages and tissue-specific genes.Real-time fluorescence quantitative analysis was used to analyze the expression of the NtPC gene family under low temperature and methyl jasmonate stress.The tobacco NtPC family contained 110 members and was divided into four subfamilies:early nodulin-like protein(NtENODL),uclacyanin-like protein,stellacyanin1-like protein,and plantacyanin-like protein.According to phylogenetic and structural analyses,the NtPC family could be divided into eight structural types.Fifty-three NtPCs were randomly distributed on 22 of 24 tobacco chromosomes.Collinearity analysis revealed 33 pairs of genes belonging to the NtPC family.Gene ontology analysis showed that the PC genes are components of the plasma membrane and may participate in plasma membrane-related functions.The NtPC family contained numerous elements related to hormonal and abiotic stress responses and was specifically expressed in the tobacco prosperous,maturation,and budding periods.Tissue-specific expression analysis showed that some genes were tissue specific.The expression of NtENODL58 and other genes was significantly induced by low-temperature and methyl jasmonate stress.Thus,the NtPC gene family plays an important role in plant stress response.展开更多
Background:To investigate the effect of long-term febrile convulsions on gene expression in mesial temporal lobe epilepsy with hippocampal sclerosis(MTLE-HS)and explore the molecular mechanism of MTLE-HS.Methods:Micro...Background:To investigate the effect of long-term febrile convulsions on gene expression in mesial temporal lobe epilepsy with hippocampal sclerosis(MTLE-HS)and explore the molecular mechanism of MTLE-HS.Methods:Microarray data of MTLE-HS were obtained from the Gene Expression Omnibus database.Differentially expressed genes(DEGs)between MTLE-HS with and without febrile seizure history were screened by the GEO2R software.Pathway enrichment and gene ontology of the DEGs were analyzed using the DAVID online database and FunRich software.Protein–protein interaction(PPI)networks among DEGs were constructed using the STRING database and analyzed by Cytoscape.Results:A total of 515 DEGs were identified in MTLE-HS samples with a febrile seizure history compared to MTLEHS samples without febrile seizure,including 25 down-regulated and 490 up-regulated genes.These DEGs were expressed mostly in plasma membrane and synaptic vesicles.The major molecular functions of those genes were voltage-gated ion channel activity,extracellular ligand-gated ion channel activity and calcium ion binding.The DEGs were mainly involved in biological pathways of cell communication signal transduction and transport.Five genes(SNAP25,SLC32A1,SYN1,GRIN1,and GRIA1)were significantly expressed in the MTLE-HS with prolonged febrile seizures.Conclusion:The pathogenesis of MTLE-HS involves multiple genes,and prolonged febrile seizures could cause differential expression of genes.Thus,investigations of those genes may provide a new perspective into the mechanism of MTLE-HS.展开更多
Ca α-Sialon compacts pressurelessly-sintered tothe intermediate temperature (1 450℃) were investigated with TEM for an overall composition Ca1.8Si6.6Al5.4O1.8N14.2. It was found that in most cases, the newly-formed ...Ca α-Sialon compacts pressurelessly-sintered tothe intermediate temperature (1 450℃) were investigated with TEM for an overall composition Ca1.8Si6.6Al5.4O1.8N14.2. It was found that in most cases, the newly-formed α-Sialon grains had no epitaxial orientation relationship with the Si3-N4 particles; only occasionally heteroepitaxial nucleation of α-Sialon on α-Si3N4 was detected. Further EDAX analysis revealed a much higher Ca concentration in the non-epi-taxially nucleated α-Sialon than in the heteroepitaxially nucleated α-Sialon. Thus a possible correlation between the concentration of metal cations in the (a-Sialon structure and the nucleation mechanism has been proposed, i.e. α-Sialon compositions with higher Ca concentration show a stronger trend of non-epitaxial nucleation.展开更多
Background:This study was designed to characterize human PRRT2 gene and protein,in order to provide theoretical reference for research on regulation of PRRT2 expression and its involvement in the pathogenesis of parox...Background:This study was designed to characterize human PRRT2 gene and protein,in order to provide theoretical reference for research on regulation of PRRT2 expression and its involvement in the pathogenesis of paroxysmal kinesigenic dyskinesia and other related diseases.Method:Biological softwares Protparam,Protscale,MHMM,SignalP 5.0,NetPhos 3.1,Swiss-Model,Promoter 2.0,AliBaba2.1 and EMBOSS were used to analyze the sequence characteristics,transcription factors of human PRRT2 and their binding sites in the promoter region of the gene,as well as the physicochemical properties,signal peptides,hydrophobicity property,transmembrane regions,protein structure,interacting proteins and functions of PRRT2 protein.Results:(1)Evolutionary analysis of PRRT2 protein showed that the human PRRT2 had closest genetic distance from Pongo abelii.(2)The human PRRT2 protein was an unstable hydrophilic protein located on the plasma membrane.(3)The forms of random coil(67.65%)and alpha helix(23.24%)constituted the main secondary structure elements of PRRT2 protein.There were also multiple potential phosphorylation sites in the protein.(4)The results of ontology analysis showed that the cellular component of PRRT2 protein was located in the plasma membrane;the molecular function of PRRT2 included syntaxin-1 binding and SH3 domain binding;the PRRT2 protein is involved in biological processes of negative regulation of soluble NSF attachment protein receptor(SNAR E)complex assembly and calcium-dependent activation of synaptic vesicle fusion.(5)String database analysis revealed 10 proteins with close interactions with the human PRRT2 protein.(6)There were at least two promoter regions in the PRRT2 gene within 2000 bp upstream the 5'flank,a 304-bp CpG island in the promoter region and four GC boxes in the 5'regulatory region of PRRT2 gene and we found 13 transcription factors that could bind the promoter region of the PRRT2 gene.Conclusion:These results provide important information for further studies on the role of PRRT2 gene and identify their functions.展开更多
基金the National Natural Science Foundation of China(No.61771316).
文摘Usually,the problem of direction-of-arrival(DOA)estimation is performed based on the assumption of uniform noise.In many applications,however,the noise across the array may be nonuniform.In this situation,the performance of DOA estimators may be deteriorated greatly if the non-uniformity of noise is ignored.To tackle this problem,we consider the problem of DOA es-timation in the presence of nonuniform noise by leveraging a singular value thresholding(SVT)based matrix completion method.Different from that the traditional SVT method apply fixed threshold,to improve the performance,the proposed method can obtain a more suitable threshold based on careful estimation of the signal-to-noise ratio(SNR)levels.Specifically,we firstly employ an SVT-based matrix completion method to estimate the noise-free covariance matrix.On this basis,the signal and noise subspaces are obtained from the eigendecomposition of the noise-free cov-ariance matrix.Finally,traditional subspace-based DOA estimation approaches can be directly ap-plied to determine the DOAs.Numerical simulations are performed to demonstrate the effective-ness of the proposed method.
文摘Purpose: To understand how authors and reviewers are accepting and embracing Open Peer Review(OPR), one of the newest innovations in the Open Science movement.Design/methodology/approach: This research collected and analyzed data from the Open Access journal Peer J over its first three years(2013–2016). Web data were scraped, cleaned, and structured using several Web tools and programs. The structured data were imported into a relational database. Data analyses were conducted using analytical tools as well as programs developed by the researchers.Findings: Peer J, which supports optional OPR, has a broad international representation of authors and referees. Approximately 73.89% of articles provide full review histories. Of the articles with published review histories, 17.61% had identities of all reviewers and 52.57% had at least one signed reviewer. In total, 43.23% of all reviews were signed. The observed proportions of signed reviews have been relatively stable over the period since the Journal’s inception.Research limitations: This research is constrained by the availability of the peer review history data. Some peer reviews were not available when the authors opted out of publishing their review histories. The anonymity of reviewers made it impossible to give an accurate count of reviewers who contributed to the review process. Practical implications: These findings shed light on the current characteristics of OPR. Given the policy that authors are encouraged to make their articles’ review history public and referees are encouraged to sign their review reports, the three years of Peer J review data demonstrate that there is still some reluctance by authors to make their reviews public and by reviewers to identify themselves. Originality/value: This is the first study to closely examine Peer J as an example of an OPR model journal. As Open Science moves further towards open research, OPR is a final and critical component. Research in this area must identify the best policies and paths towards a transparent and open peer review process for scientific communication.
基金This study was supported by the Tobacco Science Research Institute of the Chongqing Tobacco Company(A20201NY01-1305).
文摘Phytocyanin(PC)is a class of plant-specific blue copper proteins involved in electron transport,plant growth,development,and stress resistance.However,PC proteins have not been systematically evaluated in tobacco plants.We determined the whole-genome sequences of the PC family in the tobacco cultivar‘K326.’The transcriptome data were used to analyze the expression of the NtPC family at different development stages and tissue-specific genes.Real-time fluorescence quantitative analysis was used to analyze the expression of the NtPC gene family under low temperature and methyl jasmonate stress.The tobacco NtPC family contained 110 members and was divided into four subfamilies:early nodulin-like protein(NtENODL),uclacyanin-like protein,stellacyanin1-like protein,and plantacyanin-like protein.According to phylogenetic and structural analyses,the NtPC family could be divided into eight structural types.Fifty-three NtPCs were randomly distributed on 22 of 24 tobacco chromosomes.Collinearity analysis revealed 33 pairs of genes belonging to the NtPC family.Gene ontology analysis showed that the PC genes are components of the plasma membrane and may participate in plasma membrane-related functions.The NtPC family contained numerous elements related to hormonal and abiotic stress responses and was specifically expressed in the tobacco prosperous,maturation,and budding periods.Tissue-specific expression analysis showed that some genes were tissue specific.The expression of NtENODL58 and other genes was significantly induced by low-temperature and methyl jasmonate stress.Thus,the NtPC gene family plays an important role in plant stress response.
基金the Sanming Project of Medicine in Shenzhen(No.SZSM201911003)National Natural Science Foundation of China(No.81571266,81771405).
文摘Background:To investigate the effect of long-term febrile convulsions on gene expression in mesial temporal lobe epilepsy with hippocampal sclerosis(MTLE-HS)and explore the molecular mechanism of MTLE-HS.Methods:Microarray data of MTLE-HS were obtained from the Gene Expression Omnibus database.Differentially expressed genes(DEGs)between MTLE-HS with and without febrile seizure history were screened by the GEO2R software.Pathway enrichment and gene ontology of the DEGs were analyzed using the DAVID online database and FunRich software.Protein–protein interaction(PPI)networks among DEGs were constructed using the STRING database and analyzed by Cytoscape.Results:A total of 515 DEGs were identified in MTLE-HS samples with a febrile seizure history compared to MTLEHS samples without febrile seizure,including 25 down-regulated and 490 up-regulated genes.These DEGs were expressed mostly in plasma membrane and synaptic vesicles.The major molecular functions of those genes were voltage-gated ion channel activity,extracellular ligand-gated ion channel activity and calcium ion binding.The DEGs were mainly involved in biological pathways of cell communication signal transduction and transport.Five genes(SNAP25,SLC32A1,SYN1,GRIN1,and GRIA1)were significantly expressed in the MTLE-HS with prolonged febrile seizures.Conclusion:The pathogenesis of MTLE-HS involves multiple genes,and prolonged febrile seizures could cause differential expression of genes.Thus,investigations of those genes may provide a new perspective into the mechanism of MTLE-HS.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 59810760327 and 59872049).
文摘Ca α-Sialon compacts pressurelessly-sintered tothe intermediate temperature (1 450℃) were investigated with TEM for an overall composition Ca1.8Si6.6Al5.4O1.8N14.2. It was found that in most cases, the newly-formed α-Sialon grains had no epitaxial orientation relationship with the Si3-N4 particles; only occasionally heteroepitaxial nucleation of α-Sialon on α-Si3N4 was detected. Further EDAX analysis revealed a much higher Ca concentration in the non-epi-taxially nucleated α-Sialon than in the heteroepitaxially nucleated α-Sialon. Thus a possible correlation between the concentration of metal cations in the (a-Sialon structure and the nucleation mechanism has been proposed, i.e. α-Sialon compositions with higher Ca concentration show a stronger trend of non-epitaxial nucleation.
基金supported by the Sanming Project of Medicine in Shenzhen(No.SZSM201911003)Guangdong Province Medical Science and Technology Research Found project(A2018320)the National Nature Science Foundation of China(No.81571266,82071447 and 81771405).
文摘Background:This study was designed to characterize human PRRT2 gene and protein,in order to provide theoretical reference for research on regulation of PRRT2 expression and its involvement in the pathogenesis of paroxysmal kinesigenic dyskinesia and other related diseases.Method:Biological softwares Protparam,Protscale,MHMM,SignalP 5.0,NetPhos 3.1,Swiss-Model,Promoter 2.0,AliBaba2.1 and EMBOSS were used to analyze the sequence characteristics,transcription factors of human PRRT2 and their binding sites in the promoter region of the gene,as well as the physicochemical properties,signal peptides,hydrophobicity property,transmembrane regions,protein structure,interacting proteins and functions of PRRT2 protein.Results:(1)Evolutionary analysis of PRRT2 protein showed that the human PRRT2 had closest genetic distance from Pongo abelii.(2)The human PRRT2 protein was an unstable hydrophilic protein located on the plasma membrane.(3)The forms of random coil(67.65%)and alpha helix(23.24%)constituted the main secondary structure elements of PRRT2 protein.There were also multiple potential phosphorylation sites in the protein.(4)The results of ontology analysis showed that the cellular component of PRRT2 protein was located in the plasma membrane;the molecular function of PRRT2 included syntaxin-1 binding and SH3 domain binding;the PRRT2 protein is involved in biological processes of negative regulation of soluble NSF attachment protein receptor(SNAR E)complex assembly and calcium-dependent activation of synaptic vesicle fusion.(5)String database analysis revealed 10 proteins with close interactions with the human PRRT2 protein.(6)There were at least two promoter regions in the PRRT2 gene within 2000 bp upstream the 5'flank,a 304-bp CpG island in the promoter region and four GC boxes in the 5'regulatory region of PRRT2 gene and we found 13 transcription factors that could bind the promoter region of the PRRT2 gene.Conclusion:These results provide important information for further studies on the role of PRRT2 gene and identify their functions.
