Existing studies have underscored the pivotal role of N-acetyltransferase 10(NAT10) in various cancers. However, the outcomes of protein-protein interactions between NAT10 and its protein partners in head and neck squ...Existing studies have underscored the pivotal role of N-acetyltransferase 10(NAT10) in various cancers. However, the outcomes of protein-protein interactions between NAT10 and its protein partners in head and neck squamous cell carcinoma(HNSCC) remain unexplored. In this study, we identified a significant upregulation of RNA-binding protein with serine-rich domain 1(RNPS1) in HNSCC, where RNPS1 inhibits the ubiquitination degradation of NAT10 by E3 ubiquitin ligase, zinc finger SWIM domain-containing protein 6(ZSWIM6), through direct protein interaction, thereby promoting high NAT10 expression in HNSCC. This upregulated NAT10 stability mediates the enhancement of specific tRNA ac^(4)C modifications, subsequently boosting the translation process of genes involved in pathways such as IL-6 signaling, IL-8 signaling, and PTEN signaling that play roles in regulating HNSCC malignant progression, ultimately influencing the survival and prognosis of HNSCC patients. Additionally, we pioneered the development of TRMC-seq, leading to the discovery of novel t RNA-ac^(4)C modification sites, thereby providing a potent sequencing tool for tRNAac^(4)C research. Our findings expand the repertoire of tRNA ac^(4)C modifications and identify a role of tRNA ac^(4)C in the regulation of mRNA translation in HNSCC.展开更多
Gaofen-3-02(GF3-02)is the first C-band synthetic aperture radar(SAR)satellite with terrain observation with progressive scans of SAR(TOPSAR)imaging mode in China,which plays an essential role in marine environment mon...Gaofen-3-02(GF3-02)is the first C-band synthetic aperture radar(SAR)satellite with terrain observation with progressive scans of SAR(TOPSAR)imaging mode in China,which plays an essential role in marine environment monitoring.Given the weak scattering characteristics of the ocean,the system thermal noise superimposed on SAR images has significant interference,especially in cross-polarization channels.Noise-Equivalent Sigma-Zero(NESZ)is a measure of the sensitivity of the radar to areas of low backscatter.The NESZ is defined to be the scattering cross-section coefficient of an area which contributes a mean level in the image equal to the signal-independent additive noise level.For TOPSAR,NESZ exhibits the shape of the SAR scanning gain curve in the azimuth and the shape of the antenna pattern in the range.Therefore,the accurate measurement of NESZ plays a vital role in the application of spaceborne SAR sea surface cross-polarization data.This paper proposes a theoretical calculation method for the NESZ curve in GF3-02 TOPSAR mode based on SAR noise inner calibration data and the imaging algorithm.A method for correcting the error existing in the theoretical curve of NESZ is also proposed according to the relationship between sea surface backscattering and wind speed and the same characteristics of target scattering in the overlapping area of adjacent sub-swaths.According to assessment with wide-swath TOPSAR cross-polarization data,the GF3-02 TOPSAR mode has a very low thermal noise level,which is better than−33 dB at the edge of each beam,and controlled below−38 dB at the center of the beam.The two-dimensional reference curves of the NESZ of each beam are provided to the GF3-02 TOPSAR users.After discussing the relationship between normalized radar cross section(NRCS)and wind speed,we provide a formula for NRCS related to wind speed and radar incidence angle.Compared with the NRCS derived from this formula and the NESZ-subtracted NRCS of SAR images,the bias is−0.0048 dB,the Root Mean Square Error is 1.671 dB and the correlation coefficient is 0.939.展开更多
The main objective of this paper is to propose a newly developed ocean Significant Wave Height (SWH) retrieval method from Envisat Advanced Synthetic Aperture Radar (ASAR) imagery. A series of wave mode imagery from J...The main objective of this paper is to propose a newly developed ocean Significant Wave Height (SWH) retrieval method from Envisat Advanced Synthetic Aperture Radar (ASAR) imagery. A series of wave mode imagery from January, April and May of 2011 are collocated with ERA-Interim reanalysis SWH data. Based on the matched datasets, a simplified empirical relationship between 22 types of SAR imagery parameters and SWH products is developed with the Genetic Algorithms Partial Least-Squares (GA-PLS) model. Two major features of the backscattering coefficient σ0 and the frequency parameter S10 are chosen as the optimal training feature subset of SWH retrieval by using cross validation. In addition, we also present a comparison of the retrieval results of the simplified empirical relationship with the collocated ERA-Interim data. The results show that the assessment index of the correlation coefficient, the bias, the root-mean-square error of cross validation (RMSECV) and the scattering index (SI) are 0.78, 0.07 m, 0.76 m and 0.5, respectively. In addition, the comparison of the retrieved SWH data between our simplifying model and the Jason-2 radar altimeter data is proposed in our study. Moreover, we also make a comparison of the retrieval of SWH data between our developed model and the well- known CWAVE_ENV model. The results show that satisfying retrieval results are acquired in the low-moderate sea state, but major bias appears in the high sea state, especially for SWH>5 m.展开更多
Methyltransferase like 13(METTL13),a kind of methyltransferase,is implicated in protein binding and synthesis.The upregulation of METTL13 has been reported in a variety of tumors.However,little was known about its pot...Methyltransferase like 13(METTL13),a kind of methyltransferase,is implicated in protein binding and synthesis.The upregulation of METTL13 has been reported in a variety of tumors.However,little was known about its potential function in head and neck squamous cell carcinoma(HNSCC)so far.In this study,we found that METTL13 was significantly upregulated in HNSCC at both mRNA and protein level.Increased METTL13 was negatively associated with clinical prognosis.And METTL13 markedly affected HNSCC cellular phenotypes in vivo and vitro.Further mechanism study revealed that METTL13 could regulate EMT signaling pathway by mediating enhancing translation efficiency of Snail,the key transcription factor in EMT,hence regulating the progression of EMT.Furthermore,Snail was verified to mediate METTL13-induced HNSCC cell malignant phenotypes.Altogether,our study had revealed the oncogenic role of METTL13 in HNSCC,and provided a potential therapeutic strategy.展开更多
Non-blind audio bandwidth extension is a standard technique within contemporary audio codecs to efficiently code audio signals at low bitrates. In existing methods, in most cases high frequencies signal is usually gen...Non-blind audio bandwidth extension is a standard technique within contemporary audio codecs to efficiently code audio signals at low bitrates. In existing methods, in most cases high frequencies signal is usually generated by a duplication of the corresponding low frequencies and some parameters of high frequencies. However, the perception quality of coding will significantly degrade if the correlation between high frequencies and low frequencies becomes weak. In this paper, we quantitatively analyse the correlation via computing mutual information value. The analysis results show the correlation also exists in low frequency signal of the context dependent frames besides the current frame. In order to improve the perception quality of coding, we propose a novel method of high frequency coarse spectrum generation to improve the conventional replication method. In the proposed method, the coarse high frequency spectrums are generated by a nonlinear mapping model using deep recurrent neural network. The experiments confirm that the proposed method shows better performance than the reference methods.展开更多
For Virtual Reality(VR) to be truly immersive, it needs convincing sound to match. Due to the diversity of individual's anthropometric measurements, the individualized customization technology is needed to get con...For Virtual Reality(VR) to be truly immersive, it needs convincing sound to match. Due to the diversity of individual's anthropometric measurements, the individualized customization technology is needed to get convincing sound. In this paper, we proposed a simple and effective method for modeling relationships between anthropometric measurements and Head-related Impulse Response(HRIR). Considering the relationship between anthropometric measurements and different HRIR parts is complicated, we divided the HRIRs into small segments and carried out regression analysis between anthropometric measurements and each segment to establish relationship model. The results of objective simulation and subjective test indicate that the model can generate individualize HRIRs from a series of anthropometric measurements. With the individualized HRIRs, we can get more accurate acoustic localization sense than using non-individualized HRIRs.展开更多
A method for land-cover classification was proposed based on the fusion of features generated from waveform data and point cloud respectively.It aims to partially overcome the ineffectiveness of many traditional class...A method for land-cover classification was proposed based on the fusion of features generated from waveform data and point cloud respectively.It aims to partially overcome the ineffectiveness of many traditional classifiers caused by the fact that point cloud is lacking spectral information.The whole flowchart of the method is as follows:Firstly,Gaussian decomposition was applied to fit an echo full-waveform.The parameters associated with the Gaussian function were optimized by LM(Levenberg-Marquard)algorithm.Six and thirteen features were generated to describe the waveform characteristics and the local geometry of point cloud,respectively.Secondly,a random forest was selected as the classifier to which the generated features were input.Relief-F was used to rank the weights of all the features generated.Finally,features were input to the classifier one by one according to the weights calculated from feature ranking,where classification accuracies were evaluated.The experimental results show that the effectiveness of the fusion of features generated from waveform and point cloud for LiDAR data classification,with 95.4%overall accuracy,0.90 kappa coefficient,which outperform the results obtained by a single class of features,no matter whether they were generated from point cloud or waveform data.展开更多
Enhanced neurogenesis in the dentate gyrus of the hippocampus following seizure activity, especially status epilepticus, is associated with ectopic residence and aberrant integration of newborn granule cells. Hilar ec...Enhanced neurogenesis in the dentate gyrus of the hippocampus following seizure activity, especially status epilepticus, is associated with ectopic residence and aberrant integration of newborn granule cells. Hilar ectopic granule cells may be detrimental to the stability of dentate circuitry by means of their electrophysiological properties and synaptic connectivity. We hypothesized that status epilepticus also increases ectopic granule cells in the molecular layer. Status epilepticus was induced in male Sprague-Dawley rats by intraperitoneal injection of pilocarpine. Immunostaining showed that many doublecortin-positive cells were present in the molecular layer and the hilus 7 days after the induction of status epilepticus. At least 10 weeks after status epilepticus, the estimated number of cells positive for both prospero homeobox protein 1 and neuron-specific nuclear protein in the hilus was significantly increased. A similar trend was also found in the molecular layer. These findings indicate that status epilepticus can increase the numbers of mature and ectopic newborn granule cells in the molecular layer.展开更多
Object-based audio coding is the main technique of audio scene coding. It can effectively reconstruct each object trajectory, besides provide sufficient flexibility for personalized audio scene reconstruction. So more...Object-based audio coding is the main technique of audio scene coding. It can effectively reconstruct each object trajectory, besides provide sufficient flexibility for personalized audio scene reconstruction. So more and more attentions have been paid to the object-based audio coding. However, existing object-based techniques have poor sound quality because of low parameter frequency domain resolution. In order to achieve high quality audio object coding, we propose a new coding framework with introducing the non-negative matrix factorization(NMF) method. We extract object parameters with high resolution to improve sound quality, and apply NMF method to parameter coding to reduce the high bitrate caused by high resolution. And the experimental results have shown that the proposed framework can improve the coding quality by 25%, so it can provide a better solution to encode audio scene in a more flexible and higher quality way.展开更多
BACKGROUND:It is generally accepted that gentamicin can damage the cochlear nerve and acoustic nerve. In recent years,scholars have focused on neuronal changes and neurochemical information in the brainstem primary au...BACKGROUND:It is generally accepted that gentamicin can damage the cochlear nerve and acoustic nerve. In recent years,scholars have focused on neuronal changes and neurochemical information in the brainstem primary auditory center. OBJECTIVE: To explore morphological changes of choline acetyltransferase (ChAT)-positive neurons in the paraolivary nucleus (PON) of guinea pigs,and the effect on hearing following gentamicin injection. DESIGN,TIME AND SETTING: Randomized grouping and morphological observational study was performed at Animal Experimental Center of General Hospital of Shenyang Military Area Command of Chinese PLA from January to August 2007. MATERIALS: A total of 48 healthy guinea pigs were randomly divided into model (n=40) and control (n= 8) groups. The model group was divided into five subgroups at five time points of 1 and 3 days,1,2,and 3 weeks. METHODS: Guinea pigs in the model group were intraperitoneally injected with gentamicin,and those in the control group were intraperitoneally injected with the same volume of saline. MAIN OUTCOME MEASURES: Auditory brainstem-evoked potential was used to record auditory threshold; distribution and morphological changes of ChAT-positive neurons in the PON were observed with immunohistochemistry; section area and gray value of ChAT-positive neurons were measured with Quantimet 570 image-analyzing system. RESULTS: ChAT-positive neurons were diffusedly distributed in the PON. The majority was composed of large,round cells,with positive neurites that could be clearly observed. Following gentamicin injection,the positive neurons displayed an irregular outline,and their neurites began to shorten and disappear. The gray value increased with prolonged gentamicin administration (P<0.05). In addition,the somatic cross-sectional area was enlarged in the model group at 1 and 3 days after injection (P<0.05),whereas cell number significantly decreased at three weeks after injection (P<0.05). Starting at 3-4 days,behavioral features and auditory degrees became gradually aggravated with prolonged gentamicin administration (P<0.05). CONCLUSION: Gentamicin damaged ChAT-positive neurons in the PON,and long-term gentamicin treatment aggravated hearing impairment.展开更多
Impacts of microenvironments on cell migration have been reported in various interaction modes.A rapid tumor metastasis occurs along topological interfaces in vivo,such as the interface between the blood vessels and n...Impacts of microenvironments on cell migration have been reported in various interaction modes.A rapid tumor metastasis occurs along topological interfaces in vivo,such as the interface between the blood vessels and nerves.In this work,we culture MDA-MB231 cells at dish-liquid,dish-hydrogel,and hydrogel-liquid interfaces,respectively,to study how these different interfaces influence cell dynamics and morphology.Our results show that the migration mode of cells changes from an amoeboid motion to a mesenchymal motion but their speed do not change obviously if the interface changes from hydrogel-liquid to dish-liquid.In contrast,the migration mode of cells at a dish-hydrogel interface maintains as a mesenchymal motion,whereas their speed increases significantly.展开更多
In this study a novel synthetic aperture radar(SAR)scattering model for sea surface with breaking waves is proposed.Compared with existing models,the proposed model considers an empirical relationship between wind spe...In this study a novel synthetic aperture radar(SAR)scattering model for sea surface with breaking waves is proposed.Compared with existing models,the proposed model considers an empirical relationship between wind speed and wave breaking scattering to present the contribution of wave breaking.Moreover,the scattering weight factor p,and wave breaking rate q,are performed to present the contribution of the quasi-specular scattering term,Bragg scattering term,and wave breaking scattering term to the total scattering from the sea surface.To explore the modeling accuracy of sea-surface scattering,a simulated normalized radar cross-section(NRCS)and measured NRCS are compared.The proposed model generated the simulated NRCS and a matching GF-3 dataset was used for the measured NRCS.It was revealed that the performance of the VV polarization of our model was much better than that of HH polarization,with a correlation of 0.91,bias of-0.14 dB,root mean square error(RMSE)of 1.26 dB,and scattering index(SI)of-0.11.In addition,the novel model is explored and compared with the geophysical model of CMODs and satellite-measured NRCS from GF-3 SAR wave mode imagery.For an incidence angle 40°–41°,the relationship between the NRCS and wind speed,relative wind direction is proposed.As with the SAR-measured NRCS,the performance of VV polarization was much better than HH polarization,with a correlation of 0.99,bias of-0.25 dB,RMSE of 0.64 dB,and SI of-0.04.展开更多
The head-related transfer function(HRTF)involves the cues for human auditory localization,which turns it into an essential item of virtual auditory display technology.In practice,the interpolation of HRTF is necessary...The head-related transfer function(HRTF)involves the cues for human auditory localization,which turns it into an essential item of virtual auditory display technology.In practice,the interpolation of HRTF is necessary for the virtual auditory display systems to achieve high spatial resolution.Traditional geometric-based interpolation methods are generally restrained by the spatial distribution of reference on HRTF.When the spatial distribution is sparse,the accuracy of interpolation decreases significantly.Therefore,an interpolation method using the common-pole/zero model and the fitting neural network is proposed.First,we propose a common-pole/zero model to represent HRTFs across multiple subjects,in which the low-dimensional features of the measured HRTFs are extracted.Then,for a new spatial direction,we predict the corresponding low-dimensional HRTF with a fitting neural network.Finally,we reconstruct the high-dimensional HRTF from the predicted low-dimensional HRTF.The simulation results suggest that the proposed method outperforms other interpolation methods such as Linear_AMBC,Bilinear_AMBC,and the Combination method.展开更多
Recommender systems are rapidly transforming the digital world into intelligent information hubs.The valuable context information associated with the users’prior transactions has played a vital role in determining th...Recommender systems are rapidly transforming the digital world into intelligent information hubs.The valuable context information associated with the users’prior transactions has played a vital role in determining the user preferences for items or rating prediction.It has been a hot research topic in collaborative filtering-based recommender systems for the last two decades.This paper presents a novel Context Based Rating Prediction(CBRP)model with a unique similarity scoring estimation method.The proposed algorithm computes a context score for each candidate user to construct a similarity pool for the given subject user-item pair and intuitively choose the highly influential users to forecast the item ratings.The context scoring strategy has an inherent capability to incorporate multiple conditional factors to filter down the most relevant recommendations.Compared with traditional similarity estimation methods,CBRP makes it possible for the full use of neighboring collaborators’choice on various conditions.We conduct experiments on three publicly available datasets to evaluate our proposed method with random user-item pairs and got considerable improvement in prediction accuracy over the standard evaluation measures.Also,we evaluate prediction accuracy for every user-item pair in the system and the results show that our proposed framework has outperformed existing methods.展开更多
A new three-dimensional(3D) audio coding approach is presented to improve the spatial perceptual quality of 3D audio. Different from other audio coding approaches, the distance side information is also quantified, and...A new three-dimensional(3D) audio coding approach is presented to improve the spatial perceptual quality of 3D audio. Different from other audio coding approaches, the distance side information is also quantified, and the non-uniform perceptual quantization is proposed based on the spatial perception features of the human auditory system, which is named as concentric spheres spatial quantization(CSSQ) method. Comparison results were presented, which showed that a better distance perceptual quality of 3D audio can be enhanced by 5.7%~8.8% through extracting and coding the distance side information comparing with the directional audio coding, and the bit rate of our coding method is decreased of 8.07% comparing with the spatial squeeze surround audio coding.展开更多
J-aggregates of dye molecules are a unique supramolecular structure, which shows great promise in photoelectric devices due to its remarkable optical and transport properties. In this paper, we report the templated fo...J-aggregates of dye molecules are a unique supramolecular structure, which shows great promise in photoelectric devices due to its remarkable optical and transport properties. In this paper, we report the templated formation of J-aggregate nanotubes by the adsorption of 3,3’-diethylthiacarbocyanine iodide on the self-assembled nanotubes of lithocholic acid. The optical and electronic properties of the templated J-aggregate nanotubes are studied. A sensor platform is fabricated by depositing the J-aggregate nanotubes on interdigitated gold electrodes for the detection of dopamine (DA). We find that the current change of the J-aggregate nanotube-based sensor platform in response to DA is linear in the concentration range from 10 nM to 70 nM, giving the detection limit of 0.27 nM.展开更多
The use of non-halogenated solvents for the green manufacture of high-efficiency organic solar cells(OSCs)is important for their future application.However,the power conversion efficiency(PCE)of the non-halogenated so...The use of non-halogenated solvents for the green manufacture of high-efficiency organic solar cells(OSCs)is important for their future application.However,the power conversion efficiency(PCE)of the non-halogenated solvent processed OSCs is generally lower than their halogenated counterpart due to the poor film microstructure caused by the solubility issue.Herein,we propose a halogen-free solvent system to optimize film microstructure of the photovoltaic blend based on the polymer donor D18and small-molecule acceptor(SMA)L8-BO towards high-efficiency OSCs.The solvent system is consisted of a main solvent carbon disulfide and an additive paraxylene,where the former ensures the good solution-processability and promotes the solution aggregation of L8-BO,and the latter can finely control the phase-separation process by selectively dissolving the SMA.This solvent combination robustly produces a high-quality active layer,i.e.,the bicontinuous networks of donor and acceptor with nano-sized phase-separation and strongπ-πstacking.With the effective charge generation,transport and collection,the resulting device from the non-halogenated solvent system shows a high PCE of 17.50%,which is comparable to that of the device prepared from the halogenated solvent chloroform(ca.17.11%).This article proposes a new strategy for the green fabrication of high-efficiency OSCs to accelerate their industrialization.展开更多
Cellular collective motion in confluent epithelial monolayers is involved in many processes such as embryo development,carcinoma invasion,and wound healing.The development of new chemical strategies to achieve largesc...Cellular collective motion in confluent epithelial monolayers is involved in many processes such as embryo development,carcinoma invasion,and wound healing.The development of new chemical strategies to achieve largescale control of cells’collective motion is essential for biomedical applications.Here a series of DNA nanostructures with different dimensions were synthesized and their influences on cells’collective migration and packing behaviors in epithelial monolayers were investigated.We found that the framed DNA nanoassemblies effectively reduced the cells’speed by increasing the rigidity of cells,while the lipid-DNA micelles had a more pronounced effect on cells’projection area and shape factor.These DNA nanostructures all significantly enhanced the dependence of cells’speed on their shape factor.Our results indicate that cells’mobility in monolayers can be manipulated by chemical intercellular interactions without any genetic intervention.This may provide a new chemical strategy for tissue engineering and tumor therapy.展开更多
In January 2023,the hematology community in China came together for the 3rd Annual Meeting of the Chinese Alliance for Societies of Hematology(CASH).It was also the third time to announce China’s top 10 hematologic a...In January 2023,the hematology community in China came together for the 3rd Annual Meeting of the Chinese Alliance for Societies of Hematology(CASH).It was also the third time to announce China’s top 10 hematologic achievements of the previous year.Every time,both fundamental and clinical research advances were carefully considered and balanced,and the results were voted on by more than 300 committee members.Even though the first 3 CASH meetings were virtual,they were all well received,with the number of participants reaching more than 1.8 million for the 2023 CASH meeting.With the lifting of travel restrictions in China,the next CASH meeting will be hybrid.We welcome physicians,scientists,and industry representatives from China and the rest of the world to attend the next CASH meeting in 2024.展开更多
Cancer accounts for significant levels of human morbidity and mortality.Lymphoma and leukemia are representative of the blood cancers.This dictates the moral imperative for fundamental research leading to clinical app...Cancer accounts for significant levels of human morbidity and mortality.Lymphoma and leukemia are representative of the blood cancers.This dictates the moral imperative for fundamental research leading to clinical applications and therefore better outcomes,but also for conferences of transnational scope,such as the International Forum on Stem Cells,to share knowledge and experience.展开更多
基金supported by the National Natural Science Foundation of China(82173362 and 81872409)the Guangdong Basic and Applied Basic Research Foundation(2019A1515110110)。
文摘Existing studies have underscored the pivotal role of N-acetyltransferase 10(NAT10) in various cancers. However, the outcomes of protein-protein interactions between NAT10 and its protein partners in head and neck squamous cell carcinoma(HNSCC) remain unexplored. In this study, we identified a significant upregulation of RNA-binding protein with serine-rich domain 1(RNPS1) in HNSCC, where RNPS1 inhibits the ubiquitination degradation of NAT10 by E3 ubiquitin ligase, zinc finger SWIM domain-containing protein 6(ZSWIM6), through direct protein interaction, thereby promoting high NAT10 expression in HNSCC. This upregulated NAT10 stability mediates the enhancement of specific tRNA ac^(4)C modifications, subsequently boosting the translation process of genes involved in pathways such as IL-6 signaling, IL-8 signaling, and PTEN signaling that play roles in regulating HNSCC malignant progression, ultimately influencing the survival and prognosis of HNSCC patients. Additionally, we pioneered the development of TRMC-seq, leading to the discovery of novel t RNA-ac^(4)C modification sites, thereby providing a potent sequencing tool for tRNAac^(4)C research. Our findings expand the repertoire of tRNA ac^(4)C modifications and identify a role of tRNA ac^(4)C in the regulation of mRNA translation in HNSCC.
基金The National Natural Science Foundation of China under contract No.41976169.
文摘Gaofen-3-02(GF3-02)is the first C-band synthetic aperture radar(SAR)satellite with terrain observation with progressive scans of SAR(TOPSAR)imaging mode in China,which plays an essential role in marine environment monitoring.Given the weak scattering characteristics of the ocean,the system thermal noise superimposed on SAR images has significant interference,especially in cross-polarization channels.Noise-Equivalent Sigma-Zero(NESZ)is a measure of the sensitivity of the radar to areas of low backscatter.The NESZ is defined to be the scattering cross-section coefficient of an area which contributes a mean level in the image equal to the signal-independent additive noise level.For TOPSAR,NESZ exhibits the shape of the SAR scanning gain curve in the azimuth and the shape of the antenna pattern in the range.Therefore,the accurate measurement of NESZ plays a vital role in the application of spaceborne SAR sea surface cross-polarization data.This paper proposes a theoretical calculation method for the NESZ curve in GF3-02 TOPSAR mode based on SAR noise inner calibration data and the imaging algorithm.A method for correcting the error existing in the theoretical curve of NESZ is also proposed according to the relationship between sea surface backscattering and wind speed and the same characteristics of target scattering in the overlapping area of adjacent sub-swaths.According to assessment with wide-swath TOPSAR cross-polarization data,the GF3-02 TOPSAR mode has a very low thermal noise level,which is better than−33 dB at the edge of each beam,and controlled below−38 dB at the center of the beam.The two-dimensional reference curves of the NESZ of each beam are provided to the GF3-02 TOPSAR users.After discussing the relationship between normalized radar cross section(NRCS)and wind speed,we provide a formula for NRCS related to wind speed and radar incidence angle.Compared with the NRCS derived from this formula and the NESZ-subtracted NRCS of SAR images,the bias is−0.0048 dB,the Root Mean Square Error is 1.671 dB and the correlation coefficient is 0.939.
基金The National Science Foundation for Young Scientists of China under contract No.61501130the National Key Research and Development Program of China under contract Nos 2016YFB0502504 and 2016YFB0502500the National Natural Science Foundation of China under contract Nos 41431174,61471358 and 41401427
文摘The main objective of this paper is to propose a newly developed ocean Significant Wave Height (SWH) retrieval method from Envisat Advanced Synthetic Aperture Radar (ASAR) imagery. A series of wave mode imagery from January, April and May of 2011 are collocated with ERA-Interim reanalysis SWH data. Based on the matched datasets, a simplified empirical relationship between 22 types of SAR imagery parameters and SWH products is developed with the Genetic Algorithms Partial Least-Squares (GA-PLS) model. Two major features of the backscattering coefficient σ0 and the frequency parameter S10 are chosen as the optimal training feature subset of SWH retrieval by using cross validation. In addition, we also present a comparison of the retrieval results of the simplified empirical relationship with the collocated ERA-Interim data. The results show that the assessment index of the correlation coefficient, the bias, the root-mean-square error of cross validation (RMSECV) and the scattering index (SI) are 0.78, 0.07 m, 0.76 m and 0.5, respectively. In addition, the comparison of the retrieved SWH data between our simplifying model and the Jason-2 radar altimeter data is proposed in our study. Moreover, we also make a comparison of the retrieval of SWH data between our developed model and the well- known CWAVE_ENV model. The results show that satisfying retrieval results are acquired in the low-moderate sea state, but major bias appears in the high sea state, especially for SWH>5 m.
基金supported by grants from the National Natural Science Foundation of China(81872409)Natural Science Foundation of Guangdong Province(2018A030313610)+1 种基金the Open Funding of the State Key Laboratory of Oral Diseases(SKLOD2021OF02)Guangdong Basic and Applied Basic Research Foundation(2019A1515110110)。
文摘Methyltransferase like 13(METTL13),a kind of methyltransferase,is implicated in protein binding and synthesis.The upregulation of METTL13 has been reported in a variety of tumors.However,little was known about its potential function in head and neck squamous cell carcinoma(HNSCC)so far.In this study,we found that METTL13 was significantly upregulated in HNSCC at both mRNA and protein level.Increased METTL13 was negatively associated with clinical prognosis.And METTL13 markedly affected HNSCC cellular phenotypes in vivo and vitro.Further mechanism study revealed that METTL13 could regulate EMT signaling pathway by mediating enhancing translation efficiency of Snail,the key transcription factor in EMT,hence regulating the progression of EMT.Furthermore,Snail was verified to mediate METTL13-induced HNSCC cell malignant phenotypes.Altogether,our study had revealed the oncogenic role of METTL13 in HNSCC,and provided a potential therapeutic strategy.
基金supported by the National Natural Science Foundation of China under Grant No. 61762005, 61231015, 61671335, 61702472, 61701194, 61761044, 61471271National High Technology Research and Development Program of China (863 Program) under Grant No. 2015AA016306+2 种基金 Hubei Province Technological Innovation Major Project under Grant No. 2016AAA015the Science Project of Education Department of Jiangxi Province under No. GJJ150585The Opening Project of Collaborative Innovation Center for Economics Crime Investigation and Prevention Technology, Jiangxi Province, under Grant No. JXJZXTCX-025
文摘Non-blind audio bandwidth extension is a standard technique within contemporary audio codecs to efficiently code audio signals at low bitrates. In existing methods, in most cases high frequencies signal is usually generated by a duplication of the corresponding low frequencies and some parameters of high frequencies. However, the perception quality of coding will significantly degrade if the correlation between high frequencies and low frequencies becomes weak. In this paper, we quantitatively analyse the correlation via computing mutual information value. The analysis results show the correlation also exists in low frequency signal of the context dependent frames besides the current frame. In order to improve the perception quality of coding, we propose a novel method of high frequency coarse spectrum generation to improve the conventional replication method. In the proposed method, the coarse high frequency spectrums are generated by a nonlinear mapping model using deep recurrent neural network. The experiments confirm that the proposed method shows better performance than the reference methods.
基金supported by the National Key R&D Program of China(No.2017YFB1002803)the National Nature Science Foundation of China(No.61671335,No.U1736206,No.61662010)the Hubei Province Technological Innovation Major Project(No.2016AAA015)
文摘For Virtual Reality(VR) to be truly immersive, it needs convincing sound to match. Due to the diversity of individual's anthropometric measurements, the individualized customization technology is needed to get convincing sound. In this paper, we proposed a simple and effective method for modeling relationships between anthropometric measurements and Head-related Impulse Response(HRIR). Considering the relationship between anthropometric measurements and different HRIR parts is complicated, we divided the HRIRs into small segments and carried out regression analysis between anthropometric measurements and each segment to establish relationship model. The results of objective simulation and subjective test indicate that the model can generate individualize HRIRs from a series of anthropometric measurements. With the individualized HRIRs, we can get more accurate acoustic localization sense than using non-individualized HRIRs.
基金National High Resolution Earth Observation Foundation(No.11-H37B02-9001-19/22)National Natural Science Foundation of China(No.41601504)National Key R&D Program of China(No.2018YFB0504500)。
文摘A method for land-cover classification was proposed based on the fusion of features generated from waveform data and point cloud respectively.It aims to partially overcome the ineffectiveness of many traditional classifiers caused by the fact that point cloud is lacking spectral information.The whole flowchart of the method is as follows:Firstly,Gaussian decomposition was applied to fit an echo full-waveform.The parameters associated with the Gaussian function were optimized by LM(Levenberg-Marquard)algorithm.Six and thirteen features were generated to describe the waveform characteristics and the local geometry of point cloud,respectively.Secondly,a random forest was selected as the classifier to which the generated features were input.Relief-F was used to rank the weights of all the features generated.Finally,features were input to the classifier one by one according to the weights calculated from feature ranking,where classification accuracies were evaluated.The experimental results show that the effectiveness of the fusion of features generated from waveform and point cloud for LiDAR data classification,with 95.4%overall accuracy,0.90 kappa coefficient,which outperform the results obtained by a single class of features,no matter whether they were generated from point cloud or waveform data.
基金supported by grants from the Self-innovation Programs of Shandong University, No.1000069961016the National Natural Science Foundation of China, No. 81171231
文摘Enhanced neurogenesis in the dentate gyrus of the hippocampus following seizure activity, especially status epilepticus, is associated with ectopic residence and aberrant integration of newborn granule cells. Hilar ectopic granule cells may be detrimental to the stability of dentate circuitry by means of their electrophysiological properties and synaptic connectivity. We hypothesized that status epilepticus also increases ectopic granule cells in the molecular layer. Status epilepticus was induced in male Sprague-Dawley rats by intraperitoneal injection of pilocarpine. Immunostaining showed that many doublecortin-positive cells were present in the molecular layer and the hilus 7 days after the induction of status epilepticus. At least 10 weeks after status epilepticus, the estimated number of cells positive for both prospero homeobox protein 1 and neuron-specific nuclear protein in the hilus was significantly increased. A similar trend was also found in the molecular layer. These findings indicate that status epilepticus can increase the numbers of mature and ectopic newborn granule cells in the molecular layer.
基金supported by National High Technology Research and Development Program of China (863 Program) (No.2015AA016306)National Nature Science Foundation of China (No.61231015)National Nature Science Foundation of China (No.61671335)
文摘Object-based audio coding is the main technique of audio scene coding. It can effectively reconstruct each object trajectory, besides provide sufficient flexibility for personalized audio scene reconstruction. So more and more attentions have been paid to the object-based audio coding. However, existing object-based techniques have poor sound quality because of low parameter frequency domain resolution. In order to achieve high quality audio object coding, we propose a new coding framework with introducing the non-negative matrix factorization(NMF) method. We extract object parameters with high resolution to improve sound quality, and apply NMF method to parameter coding to reduce the high bitrate caused by high resolution. And the experimental results have shown that the proposed framework can improve the coding quality by 25%, so it can provide a better solution to encode audio scene in a more flexible and higher quality way.
文摘BACKGROUND:It is generally accepted that gentamicin can damage the cochlear nerve and acoustic nerve. In recent years,scholars have focused on neuronal changes and neurochemical information in the brainstem primary auditory center. OBJECTIVE: To explore morphological changes of choline acetyltransferase (ChAT)-positive neurons in the paraolivary nucleus (PON) of guinea pigs,and the effect on hearing following gentamicin injection. DESIGN,TIME AND SETTING: Randomized grouping and morphological observational study was performed at Animal Experimental Center of General Hospital of Shenyang Military Area Command of Chinese PLA from January to August 2007. MATERIALS: A total of 48 healthy guinea pigs were randomly divided into model (n=40) and control (n= 8) groups. The model group was divided into five subgroups at five time points of 1 and 3 days,1,2,and 3 weeks. METHODS: Guinea pigs in the model group were intraperitoneally injected with gentamicin,and those in the control group were intraperitoneally injected with the same volume of saline. MAIN OUTCOME MEASURES: Auditory brainstem-evoked potential was used to record auditory threshold; distribution and morphological changes of ChAT-positive neurons in the PON were observed with immunohistochemistry; section area and gray value of ChAT-positive neurons were measured with Quantimet 570 image-analyzing system. RESULTS: ChAT-positive neurons were diffusedly distributed in the PON. The majority was composed of large,round cells,with positive neurites that could be clearly observed. Following gentamicin injection,the positive neurons displayed an irregular outline,and their neurites began to shorten and disappear. The gray value increased with prolonged gentamicin administration (P<0.05). In addition,the somatic cross-sectional area was enlarged in the model group at 1 and 3 days after injection (P<0.05),whereas cell number significantly decreased at three weeks after injection (P<0.05). Starting at 3-4 days,behavioral features and auditory degrees became gradually aggravated with prolonged gentamicin administration (P<0.05). CONCLUSION: Gentamicin damaged ChAT-positive neurons in the PON,and long-term gentamicin treatment aggravated hearing impairment.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11774394 and 11704404)the Chinese Academy of Sciences(CAS),and the Key Research Program of Frontier Sciences of CAS(Grant No.QYZDB-SSW-SYS003).
文摘Impacts of microenvironments on cell migration have been reported in various interaction modes.A rapid tumor metastasis occurs along topological interfaces in vivo,such as the interface between the blood vessels and nerves.In this work,we culture MDA-MB231 cells at dish-liquid,dish-hydrogel,and hydrogel-liquid interfaces,respectively,to study how these different interfaces influence cell dynamics and morphology.Our results show that the migration mode of cells changes from an amoeboid motion to a mesenchymal motion but their speed do not change obviously if the interface changes from hydrogel-liquid to dish-liquid.In contrast,the migration mode of cells at a dish-hydrogel interface maintains as a mesenchymal motion,whereas their speed increases significantly.
基金The National Natural Science Foundation of China under contract No.4197060692。
文摘In this study a novel synthetic aperture radar(SAR)scattering model for sea surface with breaking waves is proposed.Compared with existing models,the proposed model considers an empirical relationship between wind speed and wave breaking scattering to present the contribution of wave breaking.Moreover,the scattering weight factor p,and wave breaking rate q,are performed to present the contribution of the quasi-specular scattering term,Bragg scattering term,and wave breaking scattering term to the total scattering from the sea surface.To explore the modeling accuracy of sea-surface scattering,a simulated normalized radar cross-section(NRCS)and measured NRCS are compared.The proposed model generated the simulated NRCS and a matching GF-3 dataset was used for the measured NRCS.It was revealed that the performance of the VV polarization of our model was much better than that of HH polarization,with a correlation of 0.91,bias of-0.14 dB,root mean square error(RMSE)of 1.26 dB,and scattering index(SI)of-0.11.In addition,the novel model is explored and compared with the geophysical model of CMODs and satellite-measured NRCS from GF-3 SAR wave mode imagery.For an incidence angle 40°–41°,the relationship between the NRCS and wind speed,relative wind direction is proposed.As with the SAR-measured NRCS,the performance of VV polarization was much better than HH polarization,with a correlation of 0.99,bias of-0.25 dB,RMSE of 0.64 dB,and SI of-0.04.
基金the National Key R&D Program of China(No.2017YFB1002803)National Nature Science Foundation of China(No.61801334,No.61761044)Basic Research Project of Science and Technology Plan of Shenzhen(JCYJ20170818143246278)。
文摘The head-related transfer function(HRTF)involves the cues for human auditory localization,which turns it into an essential item of virtual auditory display technology.In practice,the interpolation of HRTF is necessary for the virtual auditory display systems to achieve high spatial resolution.Traditional geometric-based interpolation methods are generally restrained by the spatial distribution of reference on HRTF.When the spatial distribution is sparse,the accuracy of interpolation decreases significantly.Therefore,an interpolation method using the common-pole/zero model and the fitting neural network is proposed.First,we propose a common-pole/zero model to represent HRTFs across multiple subjects,in which the low-dimensional features of the measured HRTFs are extracted.Then,for a new spatial direction,we predict the corresponding low-dimensional HRTF with a fitting neural network.Finally,we reconstruct the high-dimensional HRTF from the predicted low-dimensional HRTF.The simulation results suggest that the proposed method outperforms other interpolation methods such as Linear_AMBC,Bilinear_AMBC,and the Combination method.
基金This work is supported by National Natural Science Foundation of China(No.61672133)Sichuan Science and Technology Program(No.2019YFG0535)the 111 Project(No.B17008).
文摘Recommender systems are rapidly transforming the digital world into intelligent information hubs.The valuable context information associated with the users’prior transactions has played a vital role in determining the user preferences for items or rating prediction.It has been a hot research topic in collaborative filtering-based recommender systems for the last two decades.This paper presents a novel Context Based Rating Prediction(CBRP)model with a unique similarity scoring estimation method.The proposed algorithm computes a context score for each candidate user to construct a similarity pool for the given subject user-item pair and intuitively choose the highly influential users to forecast the item ratings.The context scoring strategy has an inherent capability to incorporate multiple conditional factors to filter down the most relevant recommendations.Compared with traditional similarity estimation methods,CBRP makes it possible for the full use of neighboring collaborators’choice on various conditions.We conduct experiments on three publicly available datasets to evaluate our proposed method with random user-item pairs and got considerable improvement in prediction accuracy over the standard evaluation measures.Also,we evaluate prediction accuracy for every user-item pair in the system and the results show that our proposed framework has outperformed existing methods.
基金supported by National High Technology Research and Development Program of China (863 Program, No. 2015AA016306)National Nature Science Foundation of China (No. 61662010, 61231015, 61471271, 61761044, 61762005)
文摘A new three-dimensional(3D) audio coding approach is presented to improve the spatial perceptual quality of 3D audio. Different from other audio coding approaches, the distance side information is also quantified, and the non-uniform perceptual quantization is proposed based on the spatial perception features of the human auditory system, which is named as concentric spheres spatial quantization(CSSQ) method. Comparison results were presented, which showed that a better distance perceptual quality of 3D audio can be enhanced by 5.7%~8.8% through extracting and coding the distance side information comparing with the directional audio coding, and the bit rate of our coding method is decreased of 8.07% comparing with the spatial squeeze surround audio coding.
文摘J-aggregates of dye molecules are a unique supramolecular structure, which shows great promise in photoelectric devices due to its remarkable optical and transport properties. In this paper, we report the templated formation of J-aggregate nanotubes by the adsorption of 3,3’-diethylthiacarbocyanine iodide on the self-assembled nanotubes of lithocholic acid. The optical and electronic properties of the templated J-aggregate nanotubes are studied. A sensor platform is fabricated by depositing the J-aggregate nanotubes on interdigitated gold electrodes for the detection of dopamine (DA). We find that the current change of the J-aggregate nanotube-based sensor platform in response to DA is linear in the concentration range from 10 nM to 70 nM, giving the detection limit of 0.27 nM.
基金supported by the National Natural Science Foundation of China(51873204,51933010,51773046)the 111 Project(B21005)+3 种基金the National 1000-Talent-Plan Program(1110010341)the Science and Technology Program of Shaanxi Province(2021KJXX-13)the Fundamental Research Funds for the Central Universities(GK202103104)the GIWAXS measurement at beamline 7.3.3 at the Advanced Light Source,LBNL,which is supposed by the Director,Office of Science,Office of Basic Energy Sciences,of the US Department of Energy(DE-AC02-05CH11231)。
文摘The use of non-halogenated solvents for the green manufacture of high-efficiency organic solar cells(OSCs)is important for their future application.However,the power conversion efficiency(PCE)of the non-halogenated solvent processed OSCs is generally lower than their halogenated counterpart due to the poor film microstructure caused by the solubility issue.Herein,we propose a halogen-free solvent system to optimize film microstructure of the photovoltaic blend based on the polymer donor D18and small-molecule acceptor(SMA)L8-BO towards high-efficiency OSCs.The solvent system is consisted of a main solvent carbon disulfide and an additive paraxylene,where the former ensures the good solution-processability and promotes the solution aggregation of L8-BO,and the latter can finely control the phase-separation process by selectively dissolving the SMA.This solvent combination robustly produces a high-quality active layer,i.e.,the bicontinuous networks of donor and acceptor with nano-sized phase-separation and strongπ-πstacking.With the effective charge generation,transport and collection,the resulting device from the non-halogenated solvent system shows a high PCE of 17.50%,which is comparable to that of the device prepared from the halogenated solvent chloroform(ca.17.11%).This article proposes a new strategy for the green fabrication of high-efficiency OSCs to accelerate their industrialization.
基金the National Key Research and Development Program of China(2020YFA0908200,2018YFA0902600,2020YFA0712102,and 2020YFA0712102)the National Natural Science Foundation of China(12074407,11774394,22125701,21834007,and 21907088)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDB33000000)the Youth Innovation Promotion Association of CAS(2020228,2021007).
文摘Cellular collective motion in confluent epithelial monolayers is involved in many processes such as embryo development,carcinoma invasion,and wound healing.The development of new chemical strategies to achieve largescale control of cells’collective motion is essential for biomedical applications.Here a series of DNA nanostructures with different dimensions were synthesized and their influences on cells’collective migration and packing behaviors in epithelial monolayers were investigated.We found that the framed DNA nanoassemblies effectively reduced the cells’speed by increasing the rigidity of cells,while the lipid-DNA micelles had a more pronounced effect on cells’projection area and shape factor.These DNA nanostructures all significantly enhanced the dependence of cells’speed on their shape factor.Our results indicate that cells’mobility in monolayers can be manipulated by chemical intercellular interactions without any genetic intervention.This may provide a new chemical strategy for tissue engineering and tumor therapy.
文摘In January 2023,the hematology community in China came together for the 3rd Annual Meeting of the Chinese Alliance for Societies of Hematology(CASH).It was also the third time to announce China’s top 10 hematologic achievements of the previous year.Every time,both fundamental and clinical research advances were carefully considered and balanced,and the results were voted on by more than 300 committee members.Even though the first 3 CASH meetings were virtual,they were all well received,with the number of participants reaching more than 1.8 million for the 2023 CASH meeting.With the lifting of travel restrictions in China,the next CASH meeting will be hybrid.We welcome physicians,scientists,and industry representatives from China and the rest of the world to attend the next CASH meeting in 2024.
文摘Cancer accounts for significant levels of human morbidity and mortality.Lymphoma and leukemia are representative of the blood cancers.This dictates the moral imperative for fundamental research leading to clinical applications and therefore better outcomes,but also for conferences of transnational scope,such as the International Forum on Stem Cells,to share knowledge and experience.