Endometriosis is a common chronic gynecological disease with endometrial cell implantation outside the uterus.Angiogenesis is a major pathophysiology in endometriosis.Our previous studies have demonstrated that the pr...Endometriosis is a common chronic gynecological disease with endometrial cell implantation outside the uterus.Angiogenesis is a major pathophysiology in endometriosis.Our previous studies have demonstrated that the prodrug of epigallocatechin gallate(ProEGCG)exhibits superior anti-endometriotic and anti-angiogenic effects compared to epigallocatechin gallate(EGCG).However,their direct binding targets and underlying mechanisms for the differential effects remain unknown.In this study,we demonstrated that oral ProEGCG can be effective in preventing and treating endometriosis.Additionally,1D and 2D Proteome Integral Solubility Alteration assay-based chemical proteomics identified metadherin(MTDH)and PX domain containing serine/threonine kinase-like(PXK)as novel binding targets of EGCG and ProEGCG,respectively.Computational simulation and BioLayer interferometry were used to confirm their binding affinity.Our results showed that MTDH-EGCG inhibited protein kinase B(Akt)-mediated angiogenesis,while PXK-ProEGCG inhibited epidermal growth factor(EGF)-mediated angiogenesis via the EGF/hypoxia-inducible factor(HIF-1a)/vascular endothelial growth factor(VEGF)pathway.In vitro and in vivo knockdown assays and microvascular network imaging further confirmed the involvement of these signaling pathways.Moreover,our study demonstrated that ProEGCG has superior therapeutic effects than EGCG by targeting distinct signal transduction pathways and may act as a novel antiangiogenic therapy for endometriosis.展开更多
Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysi...Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysis systems based on cobalt-based monofunctional hydrogen evolution reaction(HER)or oxygen evolution reaction(OER)catalysts have certain shortcomings in terms of resource utilization and universality.In contrast,cobalt-based bifunctional catalysts(CBCs)have attracted much attention in recent years for overall water splitting systems because of their practicality and reduced preparation cost of electrolyzer.This review aims to address the latest development in CBCs for total hydrolysis.The main modification strategies of CBCs are systematically classified in water electrolysis to provide an overview of how to regulate their morphology and electronic configuration.Then,the catalytic performance of CBCs in total-hydrolysis is summarized according to the types of cobalt-based phosphides,sulfides and oxides,and the mechanism of strengthened electrocatalytic ability is emphasized through combining experiments and theoretical calculations.Future efforts are finally suggested to focus on exploring the dynamic conversion of reaction intermediates and building near-industrial CBCs,designing advanced CBC materials through micro-modulation,and addressing commercial applications.展开更多
To study the atmospheric aging of acrylic coatings,a two-year aging exposure experiment was conducted in 13 representative climatic environments in China.An atmospheric aging evaluation model of acrylic coatings was d...To study the atmospheric aging of acrylic coatings,a two-year aging exposure experiment was conducted in 13 representative climatic environments in China.An atmospheric aging evaluation model of acrylic coatings was developed based on aging data including11 environmental factors from 567 cities.A hybrid method of random forest and Spearman correlation analysis was used to reduce the redundancy and multicollinearity of the data set by dimensionality reduction.A semi-supervised collaborative trained regression model was developed with the environmental factors as input and the low-frequency impedance modulus values of the electrochemical impedance spectra of acrylic coatings in 3.5wt%NaCl solution as output.The model improves accuracy compared to supervised learning algorithms model(support vector machines model).The model provides a new method for the rapid evaluation of the aging performance of acrylic coatings,and may also serve as a reference to evaluate the aging performance of other organic coatings.展开更多
A more general narrowband regular-shaped geometry-based statistical model(RS-GBSM) combined with the line of sight(LoS) and single bounce(SB) rays for unmanned aerial vehicle(UAV) multiple-input multiple-output(MIMO) ...A more general narrowband regular-shaped geometry-based statistical model(RS-GBSM) combined with the line of sight(LoS) and single bounce(SB) rays for unmanned aerial vehicle(UAV) multiple-input multiple-output(MIMO) channel is proposed in this paper. The channel characteristics, including space-time correlation function(STCF), Doppler power spectral density(DPSD), level crossing rate(LCR) and average fade duration(AFD), are derived based on the single sphere reference model for a non-isotropic environment. The corresponding sum-of-sinusoids(SoS) simulation models including both the deterministic model and statistical model with finite scatterers are also proposed for practicable implementation. The simulation results illustrate that the simulation models well reproduce the channel characteristics of the single sphere reference model with sufficient simulation scatterers. And the statistical model has a better approximation of the reference model in comparison with the deterministic one when the simulation trials of the stochastic model are sufficient. The effects of the parameters such as flight height, moving direction and Rice factor on the characteristics are also studied.展开更多
The uredinial stage in the life cycle of Melampsora larici-populina on poplar leaves is the most important pathogenic phase. We captured partial phases of uredinial infection in the wild, aiming to reconstruct the pro...The uredinial stage in the life cycle of Melampsora larici-populina on poplar leaves is the most important pathogenic phase. We captured partial phases of uredinial infection in the wild, aiming to reconstruct the process of uredinial ontogeny by using scanning and transmission electron microscope. At the initial infection stage, germ tubes germinated from the echinulate urediniospores. Germ tubes were frequently seen to merge with the leaf surface and cuticle breakage was observed, indicating direct hyphal penetration. Stomata penetration occurred commonly, sometimes with more than one germ tube penetrating the same stoma. Melampsora larici-populina did not form appressoria in the infection process,implying that infectious behavior of this pathogen may differ from the other rust pathogens. In general, germ tubes branched randomly, and no distinct evidence indicated that stoma could induce or orient germ tube branches. However, oriented germ tube growth has been occasionally observed in other studies. The urediniospores collapsed and finally wizened when they became nutrient stressed. At the last stage of infection, the uredinia erupted from the leaf epidermis and appeared as orange pustules on the leaf surface.展开更多
In this paper, we consider a novel two-dimensional(2D) geometry-based stochastic model(GBSM) for multiple-input multiple-output(MIMO) vehicle-to-vehicle(V2V) wideband fading channels. The proposed model employs the co...In this paper, we consider a novel two-dimensional(2D) geometry-based stochastic model(GBSM) for multiple-input multiple-output(MIMO) vehicle-to-vehicle(V2V) wideband fading channels. The proposed model employs the combination of a two-ring model and a multiple confocal ellipses model, where the signal is sum of the line-of-sight(Lo S) component, single-bounced(SB) rays, and double-bounced(DB) rays. Based on the reference model, we derive some expressions of channel statistical properties, including space-time correlation function(STCF), Doppler spectral power density(DPSD), envelope level crossing rate(LCR) and average fade duration(AFD). In addition, corresponding deterministic and stochastic simulation models are developed based on the reference model. Moreover, we compare the statistical properties of the reference model and the two simulation models in different scenarios and investigate the impact of different vehicular traffic densities(VTDs) on the channel statistical properties of the proposed model. Finally, the great agreement between simulation models and the reference model demonstrates not only the utility of simulation models, but also the correctness of theoretical derivations and simulations.展开更多
Objective To discover critical genes contributing to the sternness and maintenance of spermatogonial stem cells(SSCs)and provide new insights into the function of the leucine-rich repeat(LRR)family member Lrrc34(leudn...Objective To discover critical genes contributing to the sternness and maintenance of spermatogonial stem cells(SSCs)and provide new insights into the function of the leucine-rich repeat(LRR)family member Lrrc34(leudne-rich repeat-containing 34)in SSCs from mice.Methods Bioinformatic methods,including differentially expressed gene(DEG),gene ontology(GO)enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analyses,were used to uncover latent pluripotency-related genes.Reverse transcription-polymerase chain reaction(RT-PCR)and immunofluorescence analyses were utilized to verify the mRNA and protein expression levels,respectively.RNA interference of Lrrc34 using siRNA was performed to detect its transient impact on SSCs.Results Eight DEGs between ID4-EGFP+(G)and ID4-EGFP+/TSPAN8Hig11(TH),eight DEGs between G and ID4-EGFP+/TSPAN8Uw(TL)and eleven DEGs between TH and TL were discovered,and eleven proteinprotein interaction(PPI)modules were found to be significant in the PPI network of DEGs.One of the DEGs,Lrrc34,was selected as a potential pluripotency?related gene due to its differential expression among ID4-EGFP+spermatogonia subsets and its interaction with fibroblast growth factor 2 in the fifth module.Immunofluorescence experiments exhibited specific expression of Lrrc34 in a subpopulation of undifferentiated spermatogonia marked by LIN28A,and RT-PCR experiments confirmed the high expression of Lrrc34 in SSCs from P7 and adult mice.The transient knockdown of Lrrc34 in SSCs resulted in reduced colony sizes and significant changes in the transcriptome and apoptotic pathways.Conclusion Lrrc34 is highly expressed in mouse SSCs and is required for SSC proliferation in vitro through effects on transcriptome and signaling transduction pathways.展开更多
Adhesion plays an important role in miniaturized devices and technologies,which depends not only on indentation depth but also on the history of contact making and breaking,giving rise to adhesion hysteresis.In the pr...Adhesion plays an important role in miniaturized devices and technologies,which depends not only on indentation depth but also on the history of contact making and breaking,giving rise to adhesion hysteresis.In the present work,adhesion hysteresis has been investigated via molecular dynamics simulations on approaching and retracting a rigid tip to and from a substrate.The results show that hysteresis in the force-displacement curve that depends on approaching and retraction velocities arises under both elastic and plastic deformation.The underlying mechanisms have been analyzed.The implications of the results in friction have been discussed briefly.展开更多
电化学一氧化氮传感器能够实时监测颅内一氧化氮浓度,对于了解大脑中一氧化氮的功能至关重要.然而,在大脑中使用的传统刚性传感电极面临着灵敏度低和植入后神经炎症引起一氧化氮浓度异常的问题.在这里,我们报道了一种结合物理和化学吸...电化学一氧化氮传感器能够实时监测颅内一氧化氮浓度,对于了解大脑中一氧化氮的功能至关重要.然而,在大脑中使用的传统刚性传感电极面临着灵敏度低和植入后神经炎症引起一氧化氮浓度异常的问题.在这里,我们报道了一种结合物理和化学吸附能力、具有高灵敏度和准确性的电化学一氧化氮传感器.其对一氧化氮的物理和化学吸附能力分别来自于电极的高比表面积和丰富的羧基官能团.此外,柔软的电极可以与脑组织的力学性能相匹配,实现了一个高度适应的电极/组织界面.由此设计的颅内一氧化氮传感器表现出迄今为止所报道文献中最高的灵敏度,为3245 pA nmol^(-1)L,检测限为0.1 nmol L^(-1).电极在植入后未观察到显著的炎症反应以及过量的一氧化氮表达,提高了检测的准确性.该传感器成功捕捉了大脑中的一氧化氮波动,并实现了对多个脑区的同时检测,促进了对大脑中一氧化氮生理病理作用的研究.展开更多
Endometriosis is a common and benign angiogenesisdependent gynecological disorder,which refers to the proliferation and growth of endometrium-like tissues with neovasculature formation outside of the uterus.1 Availabl...Endometriosis is a common and benign angiogenesisdependent gynecological disorder,which refers to the proliferation and growth of endometrium-like tissues with neovasculature formation outside of the uterus.1 Available medical treatments for endometriosis containing hormonal and non-hormonal treatments had been limited for longterm usage by their side effects.2 Ideal medical treatment for endometriosis with efficacy to relieve symptoms and suppress endometriotic lesion growth and minimal side effects has been longing for decades.3 Angiogenesis is a promising therapeutic target for endometriosis.展开更多
Ischemic stroke resulting from atherosclerosis(particularly in the carotid artery)is one of the major subtypes of stroke and has a high incidence of death.Disordered lipid homeostasis,lipid deposition,local macrophage...Ischemic stroke resulting from atherosclerosis(particularly in the carotid artery)is one of the major subtypes of stroke and has a high incidence of death.Disordered lipid homeostasis,lipid deposition,local macrophage infiltration,smooth muscle cell proliferation,and plaque rupture are the main pathological processes of atherosclerotic ischemic stroke.Hepatocytes,macrophages,endothelial cells and vascular smooth muscle cells are the main cell types participating in these processes.By inhibiting the expression of the target genes in these cells,microRNAs play a key role in regulating lipid disorders and atherosclerotic ischemic stroke.In this article,we listed the microRNAs implicated in the pathology of atherosclerotic ischemic stroke and aimed to explain their pro-or antiatherosclerotic roles.Our article provides an update on the potential diagnostic use of miRNAs for detecting growing plaques and impending clinical events.Finally,we provide a perspective on the therapeutic use of local microRNA delivery and discuss the challenges for this potential therapy.展开更多
The aim of this study is to performance of a centralized open-loop evaluate the ground-water heat pump (GWHP) system for climate conditioning in Beijing with a cold climate in China. Thus, a long-time test was condu...The aim of this study is to performance of a centralized open-loop evaluate the ground-water heat pump (GWHP) system for climate conditioning in Beijing with a cold climate in China. Thus, a long-time test was conducted on a running GWHP system for the heating season from December 2011 to March 2012. The analysis of the testing data indicates that the average heat-pump coefficient of performance (COP) and the COP of the system (COPs) are 4.27 and 2.59. The low value and large fluctuation in the range of COP are found to be caused by the heat transfixion in the aquifer and the bypass in the circulation loop. Therefore, some suggestions are proposed to improve the performance for GWHPs in the cold climate region in China.展开更多
As unmanned aerial vehicles(UAV)deploy-ment is shifting from military to civilian sectors,and in particular as a means of facilitating more flexible and versatile wireless communications,the UAV channels that were pre...As unmanned aerial vehicles(UAV)deploy-ment is shifting from military to civilian sectors,and in particular as a means of facilitating more flexible and versatile wireless communications,the UAV channels that were previously not well understood are attracting increasing research and investigation.As the key component facilitating the UAV-aided communications,UAV channel characteristics and modeling are of critical importance to the designed UAV system to achieve satisfactory performance.In this article,we will provide a comprehensive overview and the future perspective of envisioned UAV communication system benefits,the existing and needed UAV channel measurements and modeling approaches,together with the new viewpoint of UAV channel applications in different communication and networking layers.Both existing work and future directions are extensively covered.展开更多
The onset of dynamic friction plays an important role in the study of sliding interfaces.Previously,the sliding precursors in the form of crack-like defects have been detected in experiments and their strain fields ha...The onset of dynamic friction plays an important role in the study of sliding interfaces.Previously,the sliding precursors in the form of crack-like defects have been detected in experiments and their strain fields have been measured to be comparable to those of moving cracks.In the present work,we considered the dynamics of sliding precursors by solving the elastic problem due to a moving dislocation in a half-plane and the transient emission of a dislocation at the edge.It has been found that both the strain field of a moving dislocation and the spatiotemporal evolution agree well with those of a sliding precursor detected in experiments.The results may cast new light to the dynamics of sliding onset.展开更多
Unlike biological materials that can sense mechanical force and actively remodel locally,synthetic polymers typically break down under stress.Molecular-level responses to damage with both stress-reporting and self-str...Unlike biological materials that can sense mechanical force and actively remodel locally,synthetic polymers typically break down under stress.Molecular-level responses to damage with both stress-reporting and self-strengthening functions are significant yet difficult to realize for synthetic polymers.To overcome this challenge,chemo-mechanical coupling into polymers that can simultaneously ameliorate mechanical,optical,or other functional properties of a polymer combined with mechanical treatment will offer a new principle for materials design.Here,we report a kind of elastomer in which destructive forces are channelled into productive and bond-forming reactions by using diselenide(Se–Se)as a mechanophore.Polyurethane has been functionalized with labile Se–Se bonds,whosemechanical activation generates seleno radicals that trigger radical transfer and cross-linking reactions in situ.These reactions are activated efficiently in a mechanical way by compression in bulk materials.The resulting covalent networks possess turn-on mechano-fluorescence and increased moduli,which provide the functions of stress reporting,mechano-healing,and mechano-remodeling for the deformed film.This study not only illuminates themechano-responsive nature of Se–Se bonds in the bulk state but also paves the way for the development of new stress-responsive materials.展开更多
Detection of sentinel lymph nodes(SLNs)is critical to guide the treatment of breast cancer.However,distinguishing metastatic SLNs from normal and inflamed lymph nodes(LNs)during surgical resection remains a challenge....Detection of sentinel lymph nodes(SLNs)is critical to guide the treatment of breast cancer.However,distinguishing metastatic SLNs from normal and inflamed lymph nodes(LNs)during surgical resection remains a challenge.Here,we report a CD44 and scavenger receptor class B1 dual-targeting hyaluronic acid nanoparticle(5K-HA-HPPS)loaded with the near-infra-red fluorescent dye DiR-BOA for SLN imaging in breast cancer.The small sized(~40 nm)self-assembled 5K-HA-HPPSs accumulated rapidly in the SLNs after intradermal injection.Compared with normal popliteal LNs(N-LN),there were ~3.2-fold and ~2.4-fold increases in fluorescence intensity in tumour metastatic SLNs(T-MLN)and inflamed LNs(Inf-LN),respectively,6 h after nanoparticle inoculation.More importantly,photoacoustic microscopy(PAM)of 5KHA-HPPS showed a significantly distinct distribution in T-MLN compared with N-LN and Inf-LN.Signals were mainly distributed at the centre of T-MLN but at the periphery of N-LN and Inf-LN.The ratio of PA intensity(R)at the centre of the LNs compared with that at the periphery was 5.93±0.75 for T-MLNs of the 5K-HA-HPPS group,which was much higher than that for the Inf-LNs(R=0.2±0.07)and N-LNs(R=0.45±0.09).These results suggest that 5K-HA-HPPS injection combined with PAM provides a powerful tool for distinguishing metastatic SLNs from pLNs and inflamed LNs,thus guiding the removal of SLNs during breast cancer surgery.展开更多
基金supported by the GRF RGC&CRF,Hong Kong(Grant Nos.:475012 and C5045-20 EF)HMRF,Hong Kong(Grant No.:03141386)+3 种基金ITF,Hong Kong(Grant No.:ITS/209/12)UGC Direct Grant 2011,2012,2021.032HKOG Trust Fund 2011,2014,2019the National Natural Science Foundation of China(Grant Nos.:81974225 and 82201823)。
文摘Endometriosis is a common chronic gynecological disease with endometrial cell implantation outside the uterus.Angiogenesis is a major pathophysiology in endometriosis.Our previous studies have demonstrated that the prodrug of epigallocatechin gallate(ProEGCG)exhibits superior anti-endometriotic and anti-angiogenic effects compared to epigallocatechin gallate(EGCG).However,their direct binding targets and underlying mechanisms for the differential effects remain unknown.In this study,we demonstrated that oral ProEGCG can be effective in preventing and treating endometriosis.Additionally,1D and 2D Proteome Integral Solubility Alteration assay-based chemical proteomics identified metadherin(MTDH)and PX domain containing serine/threonine kinase-like(PXK)as novel binding targets of EGCG and ProEGCG,respectively.Computational simulation and BioLayer interferometry were used to confirm their binding affinity.Our results showed that MTDH-EGCG inhibited protein kinase B(Akt)-mediated angiogenesis,while PXK-ProEGCG inhibited epidermal growth factor(EGF)-mediated angiogenesis via the EGF/hypoxia-inducible factor(HIF-1a)/vascular endothelial growth factor(VEGF)pathway.In vitro and in vivo knockdown assays and microvascular network imaging further confirmed the involvement of these signaling pathways.Moreover,our study demonstrated that ProEGCG has superior therapeutic effects than EGCG by targeting distinct signal transduction pathways and may act as a novel antiangiogenic therapy for endometriosis.
基金financially supported by the National Natural Science Foundation of China(51572166,52102070)the Program for Professor of Special Appointment at Shanghai Institutions of Higher Learning(GZ2020012)+4 种基金the Key Research Project of Zhejiang Laboratory(2021PE0AC02)the China Postdoctoral Science Foundation(2021M702073)BAJC R&D Fund Projects(BA23011)Australian Research Council Future Fellowships(FT230100436)the Shanghai Technical Service Center for Advanced Ceramics Structure Design and Precision Manufacturing(20DZ2294000)。
文摘Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysis systems based on cobalt-based monofunctional hydrogen evolution reaction(HER)or oxygen evolution reaction(OER)catalysts have certain shortcomings in terms of resource utilization and universality.In contrast,cobalt-based bifunctional catalysts(CBCs)have attracted much attention in recent years for overall water splitting systems because of their practicality and reduced preparation cost of electrolyzer.This review aims to address the latest development in CBCs for total hydrolysis.The main modification strategies of CBCs are systematically classified in water electrolysis to provide an overview of how to regulate their morphology and electronic configuration.Then,the catalytic performance of CBCs in total-hydrolysis is summarized according to the types of cobalt-based phosphides,sulfides and oxides,and the mechanism of strengthened electrocatalytic ability is emphasized through combining experiments and theoretical calculations.Future efforts are finally suggested to focus on exploring the dynamic conversion of reaction intermediates and building near-industrial CBCs,designing advanced CBC materials through micro-modulation,and addressing commercial applications.
基金the National Key R&D Program of China(2023YFB3812901)the Postdoctoral Fellowship Program of CPSF(No.GZC20230239)+1 种基金the China Postdoctoral Science Foundation(No.2023M740219)the National Natural Science Foundation of China(No.22209094)。
文摘To study the atmospheric aging of acrylic coatings,a two-year aging exposure experiment was conducted in 13 representative climatic environments in China.An atmospheric aging evaluation model of acrylic coatings was developed based on aging data including11 environmental factors from 567 cities.A hybrid method of random forest and Spearman correlation analysis was used to reduce the redundancy and multicollinearity of the data set by dimensionality reduction.A semi-supervised collaborative trained regression model was developed with the environmental factors as input and the low-frequency impedance modulus values of the electrochemical impedance spectra of acrylic coatings in 3.5wt%NaCl solution as output.The model improves accuracy compared to supervised learning algorithms model(support vector machines model).The model provides a new method for the rapid evaluation of the aging performance of acrylic coatings,and may also serve as a reference to evaluate the aging performance of other organic coatings.
基金supported by the National key Research and Development Program of China (2019YFC1709500)the National Collaboration Project of Critical Illness by Integrating Chinese Medicine and Western Medicine+8 种基金the Project of Heilongjiang Province Innovation Team “Tou Yan”the Yi-Xun Liu and Xiao-Ke Wu Academician Workstationthe Innovation Team of Reproductive Technique with Integrative Chinese Medicine and Western Medicine in Xuzhou City, ChinaHeilongjiang University of Chinese Medicine from the National Clinical Trial BaseHeilongjiang Provincial Clinical Research Center for Ovary Diseasesthe Research Grant Council (T13-602/21-N, C5045-20EF, and 14122021)Food and Health Bureau in Hong Kong, China (06171026)supported by a National Health and Medical Research Council (NHMRC) Investigator grant (GNT1176437)travel support from Merck.
基金supported in part by the National Natural Science Foundation of China under Grant 61622101 and Grant 61571020National Science and Technology Major Project under Grant 2018ZX03001031
文摘A more general narrowband regular-shaped geometry-based statistical model(RS-GBSM) combined with the line of sight(LoS) and single bounce(SB) rays for unmanned aerial vehicle(UAV) multiple-input multiple-output(MIMO) channel is proposed in this paper. The channel characteristics, including space-time correlation function(STCF), Doppler power spectral density(DPSD), level crossing rate(LCR) and average fade duration(AFD), are derived based on the single sphere reference model for a non-isotropic environment. The corresponding sum-of-sinusoids(SoS) simulation models including both the deterministic model and statistical model with finite scatterers are also proposed for practicable implementation. The simulation results illustrate that the simulation models well reproduce the channel characteristics of the single sphere reference model with sufficient simulation scatterers. And the statistical model has a better approximation of the reference model in comparison with the deterministic one when the simulation trials of the stochastic model are sufficient. The effects of the parameters such as flight height, moving direction and Rice factor on the characteristics are also studied.
基金financially supported by the Key Forestry Public Welfare Project(201304102)the National Natural Science Foundation(No.31400563)+3 种基金the Key Project of Jiangsu Foundation of Natural Sciences for High Education(10KJA180018)the Natural Science Foundation of Jiangsu Province(BK20130968)supported by the program for Innovative Research Teams in the Universities of Jiangsu Province and the Educational Department of Chinathe Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions
文摘The uredinial stage in the life cycle of Melampsora larici-populina on poplar leaves is the most important pathogenic phase. We captured partial phases of uredinial infection in the wild, aiming to reconstruct the process of uredinial ontogeny by using scanning and transmission electron microscope. At the initial infection stage, germ tubes germinated from the echinulate urediniospores. Germ tubes were frequently seen to merge with the leaf surface and cuticle breakage was observed, indicating direct hyphal penetration. Stomata penetration occurred commonly, sometimes with more than one germ tube penetrating the same stoma. Melampsora larici-populina did not form appressoria in the infection process,implying that infectious behavior of this pathogen may differ from the other rust pathogens. In general, germ tubes branched randomly, and no distinct evidence indicated that stoma could induce or orient germ tube branches. However, oriented germ tube growth has been occasionally observed in other studies. The urediniospores collapsed and finally wizened when they became nutrient stressed. At the last stage of infection, the uredinia erupted from the leaf epidermis and appeared as orange pustules on the leaf surface.
基金supported in part by the project from the ZTEthe National Natural Science Foundation of China under Grant 61622101 and Grant 61571020National Science and Technology Major Project under Grant 2018ZX03001031
文摘In this paper, we consider a novel two-dimensional(2D) geometry-based stochastic model(GBSM) for multiple-input multiple-output(MIMO) vehicle-to-vehicle(V2V) wideband fading channels. The proposed model employs the combination of a two-ring model and a multiple confocal ellipses model, where the signal is sum of the line-of-sight(Lo S) component, single-bounced(SB) rays, and double-bounced(DB) rays. Based on the reference model, we derive some expressions of channel statistical properties, including space-time correlation function(STCF), Doppler spectral power density(DPSD), envelope level crossing rate(LCR) and average fade duration(AFD). In addition, corresponding deterministic and stochastic simulation models are developed based on the reference model. Moreover, we compare the statistical properties of the reference model and the two simulation models in different scenarios and investigate the impact of different vehicular traffic densities(VTDs) on the channel statistical properties of the proposed model. Finally, the great agreement between simulation models and the reference model demonstrates not only the utility of simulation models, but also the correctness of theoretical derivations and simulations.
基金grants from the National Key Research and Development Program of China(2018YFC1003500)the CAMS Innovation Fund for Medical Sciences(2017-I2M-3-009,2016-12M-1-001,and 2017-I2M-1-004)+1 种基金the National Natural Science Foundation of China(81672472 and 31970794)the State Key Laboratory Special Fund from the Ministry of Science of China(2060204).
文摘Objective To discover critical genes contributing to the sternness and maintenance of spermatogonial stem cells(SSCs)and provide new insights into the function of the leucine-rich repeat(LRR)family member Lrrc34(leudne-rich repeat-containing 34)in SSCs from mice.Methods Bioinformatic methods,including differentially expressed gene(DEG),gene ontology(GO)enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analyses,were used to uncover latent pluripotency-related genes.Reverse transcription-polymerase chain reaction(RT-PCR)and immunofluorescence analyses were utilized to verify the mRNA and protein expression levels,respectively.RNA interference of Lrrc34 using siRNA was performed to detect its transient impact on SSCs.Results Eight DEGs between ID4-EGFP+(G)and ID4-EGFP+/TSPAN8Hig11(TH),eight DEGs between G and ID4-EGFP+/TSPAN8Uw(TL)and eleven DEGs between TH and TL were discovered,and eleven proteinprotein interaction(PPI)modules were found to be significant in the PPI network of DEGs.One of the DEGs,Lrrc34,was selected as a potential pluripotency?related gene due to its differential expression among ID4-EGFP+spermatogonia subsets and its interaction with fibroblast growth factor 2 in the fifth module.Immunofluorescence experiments exhibited specific expression of Lrrc34 in a subpopulation of undifferentiated spermatogonia marked by LIN28A,and RT-PCR experiments confirmed the high expression of Lrrc34 in SSCs from P7 and adult mice.The transient knockdown of Lrrc34 in SSCs resulted in reduced colony sizes and significant changes in the transcriptome and apoptotic pathways.Conclusion Lrrc34 is highly expressed in mouse SSCs and is required for SSC proliferation in vitro through effects on transcriptome and signaling transduction pathways.
基金the National Natural Science Foundation of China(NSFC)under Grant Nos.12172249,12192212,and 12021002.
文摘Adhesion plays an important role in miniaturized devices and technologies,which depends not only on indentation depth but also on the history of contact making and breaking,giving rise to adhesion hysteresis.In the present work,adhesion hysteresis has been investigated via molecular dynamics simulations on approaching and retracting a rigid tip to and from a substrate.The results show that hysteresis in the force-displacement curve that depends on approaching and retraction velocities arises under both elastic and plastic deformation.The underlying mechanisms have been analyzed.The implications of the results in friction have been discussed briefly.
基金financially supported by the National Natural Science Foundation of China (22175086, 22005137, 22205098, and 82201992)the Natural Science Foundation of Jiangsu Province (BK20200321 and BK20210681)+5 种基金the Postdoctoral Research Foundation of Jiangsu Province (2021K007A)China Postdoctoral Science Foundation (2021M700067)the National Postdoctoral Program for Innovative Talents (BX20200161)the Program for Innovative Talents and Entrepreneurs in Jiangsu (JSSCTD202138)the Fundamental Research Funds for the Central Universities (021314380234)the Natural Science Foundation of Nanjing University of Chinese Medicine (XPT82201992)。
文摘电化学一氧化氮传感器能够实时监测颅内一氧化氮浓度,对于了解大脑中一氧化氮的功能至关重要.然而,在大脑中使用的传统刚性传感电极面临着灵敏度低和植入后神经炎症引起一氧化氮浓度异常的问题.在这里,我们报道了一种结合物理和化学吸附能力、具有高灵敏度和准确性的电化学一氧化氮传感器.其对一氧化氮的物理和化学吸附能力分别来自于电极的高比表面积和丰富的羧基官能团.此外,柔软的电极可以与脑组织的力学性能相匹配,实现了一个高度适应的电极/组织界面.由此设计的颅内一氧化氮传感器表现出迄今为止所报道文献中最高的灵敏度,为3245 pA nmol^(-1)L,检测限为0.1 nmol L^(-1).电极在植入后未观察到显著的炎症反应以及过量的一氧化氮表达,提高了检测的准确性.该传感器成功捕捉了大脑中的一氧化氮波动,并实现了对多个脑区的同时检测,促进了对大脑中一氧化氮生理病理作用的研究.
基金the Strategic Seed Funding for Collaborative Research Scheme(SSFCRS)of the Chinese University of Hong Kong(CUHK,China)(No.0670/22)the National Natural Science Foundation of China(No.82260948).
文摘Endometriosis is a common and benign angiogenesisdependent gynecological disorder,which refers to the proliferation and growth of endometrium-like tissues with neovasculature formation outside of the uterus.1 Available medical treatments for endometriosis containing hormonal and non-hormonal treatments had been limited for longterm usage by their side effects.2 Ideal medical treatment for endometriosis with efficacy to relieve symptoms and suppress endometriotic lesion growth and minimal side effects has been longing for decades.3 Angiogenesis is a promising therapeutic target for endometriosis.
文摘Ischemic stroke resulting from atherosclerosis(particularly in the carotid artery)is one of the major subtypes of stroke and has a high incidence of death.Disordered lipid homeostasis,lipid deposition,local macrophage infiltration,smooth muscle cell proliferation,and plaque rupture are the main pathological processes of atherosclerotic ischemic stroke.Hepatocytes,macrophages,endothelial cells and vascular smooth muscle cells are the main cell types participating in these processes.By inhibiting the expression of the target genes in these cells,microRNAs play a key role in regulating lipid disorders and atherosclerotic ischemic stroke.In this article,we listed the microRNAs implicated in the pathology of atherosclerotic ischemic stroke and aimed to explain their pro-or antiatherosclerotic roles.Our article provides an update on the potential diagnostic use of miRNAs for detecting growing plaques and impending clinical events.Finally,we provide a perspective on the therapeutic use of local microRNA delivery and discuss the challenges for this potential therapy.
文摘The aim of this study is to performance of a centralized open-loop evaluate the ground-water heat pump (GWHP) system for climate conditioning in Beijing with a cold climate in China. Thus, a long-time test was conducted on a running GWHP system for the heating season from December 2011 to March 2012. The analysis of the testing data indicates that the average heat-pump coefficient of performance (COP) and the COP of the system (COPs) are 4.27 and 2.59. The low value and large fluctuation in the range of COP are found to be caused by the heat transfixion in the aquifer and the bypass in the circulation loop. Therefore, some suggestions are proposed to improve the performance for GWHPs in the cold climate region in China.
基金supported by the Ministry National Key Research and Development Project under Grant 2017YFE0121400the National Science and Technology Major Project under Grant 2018ZX03001031+3 种基金Shenzhen Fundamental Research Fund under Grant No.JCYJ20170411102217994Guangdong province under grant No.2017ZT07X152the Open Research Fund from Shenzhen Research Institute of Big Data under Grant No.2019ORF01006the National Natural Science Foundation of China under Grants 61622101 and 61571020.
文摘As unmanned aerial vehicles(UAV)deploy-ment is shifting from military to civilian sectors,and in particular as a means of facilitating more flexible and versatile wireless communications,the UAV channels that were previously not well understood are attracting increasing research and investigation.As the key component facilitating the UAV-aided communications,UAV channel characteristics and modeling are of critical importance to the designed UAV system to achieve satisfactory performance.In this article,we will provide a comprehensive overview and the future perspective of envisioned UAV communication system benefits,the existing and needed UAV channel measurements and modeling approaches,together with the new viewpoint of UAV channel applications in different communication and networking layers.Both existing work and future directions are extensively covered.
基金The authors are grateful for the support by the National Natural Science Foundation of China under Grant Nos.1177220,12021002 and 11572216.
文摘The onset of dynamic friction plays an important role in the study of sliding interfaces.Previously,the sliding precursors in the form of crack-like defects have been detected in experiments and their strain fields have been measured to be comparable to those of moving cracks.In the present work,we considered the dynamics of sliding precursors by solving the elastic problem due to a moving dislocation in a half-plane and the transient emission of a dislocation at the edge.It has been found that both the strain field of a moving dislocation and the spatiotemporal evolution agree well with those of a sliding precursor detected in experiments.The results may cast new light to the dynamics of sliding onset.
基金support of this research by the National Natural Science Foundation of China(grant nos.21734006 and 21975178)the National Key Research and Development Program of China(grant nos.2017YFA0207800 and 2017YFA0204503)is gratefully acknowledged.
文摘Unlike biological materials that can sense mechanical force and actively remodel locally,synthetic polymers typically break down under stress.Molecular-level responses to damage with both stress-reporting and self-strengthening functions are significant yet difficult to realize for synthetic polymers.To overcome this challenge,chemo-mechanical coupling into polymers that can simultaneously ameliorate mechanical,optical,or other functional properties of a polymer combined with mechanical treatment will offer a new principle for materials design.Here,we report a kind of elastomer in which destructive forces are channelled into productive and bond-forming reactions by using diselenide(Se–Se)as a mechanophore.Polyurethane has been functionalized with labile Se–Se bonds,whosemechanical activation generates seleno radicals that trigger radical transfer and cross-linking reactions in situ.These reactions are activated efficiently in a mechanical way by compression in bulk materials.The resulting covalent networks possess turn-on mechano-fluorescence and increased moduli,which provide the functions of stress reporting,mechano-healing,and mechano-remodeling for the deformed film.This study not only illuminates themechano-responsive nature of Se–Se bonds in the bulk state but also paves the way for the development of new stress-responsive materials.
基金supported by the National Science Fund for Distinguished Young Scholars(81625012)the National Natural Science Foundation of China(61721092)+2 种基金the Fundamental Research Funds for the Central Universities(2019kfyXMBZ022)Programme for HUST Academic Frontier Youth Team(Zhang,Z.H.)the Innovation Fund of WNLO.
文摘Detection of sentinel lymph nodes(SLNs)is critical to guide the treatment of breast cancer.However,distinguishing metastatic SLNs from normal and inflamed lymph nodes(LNs)during surgical resection remains a challenge.Here,we report a CD44 and scavenger receptor class B1 dual-targeting hyaluronic acid nanoparticle(5K-HA-HPPS)loaded with the near-infra-red fluorescent dye DiR-BOA for SLN imaging in breast cancer.The small sized(~40 nm)self-assembled 5K-HA-HPPSs accumulated rapidly in the SLNs after intradermal injection.Compared with normal popliteal LNs(N-LN),there were ~3.2-fold and ~2.4-fold increases in fluorescence intensity in tumour metastatic SLNs(T-MLN)and inflamed LNs(Inf-LN),respectively,6 h after nanoparticle inoculation.More importantly,photoacoustic microscopy(PAM)of 5KHA-HPPS showed a significantly distinct distribution in T-MLN compared with N-LN and Inf-LN.Signals were mainly distributed at the centre of T-MLN but at the periphery of N-LN and Inf-LN.The ratio of PA intensity(R)at the centre of the LNs compared with that at the periphery was 5.93±0.75 for T-MLNs of the 5K-HA-HPPS group,which was much higher than that for the Inf-LNs(R=0.2±0.07)and N-LNs(R=0.45±0.09).These results suggest that 5K-HA-HPPS injection combined with PAM provides a powerful tool for distinguishing metastatic SLNs from pLNs and inflamed LNs,thus guiding the removal of SLNs during breast cancer surgery.