Dear Editor, Collision avoidance is critical for safe operations of multiple autonomous surface vehicles(ASVs). It is a challenging task to design collision-free control laws to ensure safety, especially in a crowded ...Dear Editor, Collision avoidance is critical for safe operations of multiple autonomous surface vehicles(ASVs). It is a challenging task to design collision-free control laws to ensure safety, especially in a crowded sea environment. This letter presents a collision-free pointto-point transition strategy for multiple ASVs subject to static obstacles, dynamic obstacles and neighboring ASVs based on control barrier functions(CBFs).展开更多
Gastrointestinal cancers are a public health problem that threatens the lives of human being. A good experimental model is a powerful tool to promote the uncovering pathogenesis and establish novel treatment methods. ...Gastrointestinal cancers are a public health problem that threatens the lives of human being. A good experimental model is a powerful tool to promote the uncovering pathogenesis and establish novel treatment methods. High-quality biomedical research requires experimental models to recapitulate the physiological and pathological states of their parental tissues as much as possible. Organoids are such experimental models. Organoids refer to small organlike cellular clusters formed by the expansion and passaging of living tissues in 3D culture medium in vitro.Organoids are highly similar to the original tissues in terms of cellular composition, cell functions, and genomic profiling. Organoids have many advantages, such as short preparation cycles, long-term storage based on cryopreservation, and reusability. In recent years, researchers carried out the establishment of organoids from gastrointestinal mucosa and cancer tissues, and accumulated valuable experiences. In order to promote effective usage and further development of organoid-related technologies in the research of gastrointestinal diseases, this study proposes a benchmark based on utilization of available experimental consumables and reagents, which are involved in the key steps such as collection and pretreatment of biospecimen, organoid construction, organoid cryopreservation and recovery, growth status evaluation, and organoid quality control. We believe that the standard for the construction and preservation of organoids derived from human gastrointestinal epithelium and cancer tissues can provide an important reference for the majority of scientific researchers.展开更多
With the rapid development of wind power, the large-scale wind power integration brings a new range of issues in dispatching operation. In order to gain a better grasp of the influence caused by wind power combined to...With the rapid development of wind power, the large-scale wind power integration brings a new range of issues in dispatching operation. In order to gain a better grasp of the influence caused by wind power combined to the grid, the paper first establishes the impact characteristic indexes, and then analyzes the regularity of wind power time series in different spatial and temporal scales. At last, according to the analysis results, this paper assesses the impact of time-series characteristics of wind power on power grid, such as the frequency regulation, peak load regulation, which can provide the reference for wind power optimal dispatching of Jilin Power Grid.展开更多
Objective: The present study was designed to investigate whether quercetin exerts increasing chemosensitivity on human lung adenocarcinoma cells when quercetin combined with cisplatin (DDP) and vincristine (VCR) in vi...Objective: The present study was designed to investigate whether quercetin exerts increasing chemosensitivity on human lung adenocarcinoma cells when quercetin combined with cisplatin (DDP) and vincristine (VCR) in vitro respectively and its possible antitumor mechanism. To provide experimental proof for clinical combination application. Methods: Using intermittent administration of high dose VCR, human lung adenocarcinoma sensitive cell line (A549/S) was induced to VCR-resistant human lung adenocarcinoma cell line (A549/VCR). MTT assay was adapted for examing the 50% inhibition (IC50) value of DDP and VCR on A549/S and A549/VCR when quercetin combined with DDP and VCR respectively. Results: IC50 of DDP on A549/S and A549/VCR was 10.18 and 12.35 mg/L, and the IC50 of VCR on the two cell lines was 1.21 and 12.77 mg/L, respectively. The resistance fold of A549/VCR on VCR and DDP was 10.55 and 1.21, respectively. When quercetin at concentration of 50, 100 and 200 μmol/L in combination with DDP and VCR respectively, the IC50 of DDP and VCR on A549/S and A549/VCR were obvious decreased (P < 0.05 - P < 0.01). Conclusion: The experiment results suggested that quercetin could increase the chemosensitivity and partly revise the resistance of A549/VCR.展开更多
Finite control set model predictive torque control(FCS-MPTC)has become increasingly prevalent for induction motors(IM)owing to its simple concept,easy incorporation of constraints and strong flexibility.In traditional...Finite control set model predictive torque control(FCS-MPTC)has become increasingly prevalent for induction motors(IM)owing to its simple concept,easy incorporation of constraints and strong flexibility.In traditional FCS-MPTC speed controller design,a classical proportional integral(PI)controller is typically chosen to generate the torque reference.However,the PI controller is dependent on system parameters and sensitive to the load torque variation,which seriously affects control performance.In this paper,a model predictive torque control using sliding mode control(MPTC+SMC)for IM is proposed to enhance the robust performance of the drive system.First,the influence of the parameter mismatches for FCS-MPTC is analyzed.Second,the shortcomings of traditional PI controller are derived.Then,the proposed MPTC+SMC method is designed,and the MPTC+PI and MPTC+SMC are compared theoretically.Finally,experimental results demonstrate the correctness and effectiveness of the proposed MPTC+SMC.In comparison with MPTC+PI,MPTC+SMC has the better dynamic performance and stronger robust performance against parameter variations and load disturbance.展开更多
Clustering analysis plays a very important role in the field of data mining,image segmentation and pattern recognition.The method of cluster analysis is introduced to analyze NetEYun music data.In addition,different t...Clustering analysis plays a very important role in the field of data mining,image segmentation and pattern recognition.The method of cluster analysis is introduced to analyze NetEYun music data.In addition,different types of music data are clustered to find the commonness among the same kind of music.A music data-oriented clustering analysis method is proposed:Firstly,the audio beat period is calculated by reading the audio file data,and the emotional features of the audio are extracted;Secondly,the audio beat period is calculated by Fourier transform.Finally,a clustering algorithm is designed to obtain the clustering results of music data.展开更多
Background and Aims:Timely and effective assessment scoring systems for predicting the mortality of patients with hepatitis E virus-related acute liver failure(HEV-ALF)are urgently needed.The present study aimed to es...Background and Aims:Timely and effective assessment scoring systems for predicting the mortality of patients with hepatitis E virus-related acute liver failure(HEV-ALF)are urgently needed.The present study aimed to establish an effective nomogram for predicting the mortality of HEV-ALF patients.Methods:The nomogram was based on a cross-sectional set of 404 HEV-ALF patients who were identified and enrolled from a cohort of 650 patients with liver failure.To compare the performance with that of the model for end-stage liver disease(MELD)scoring and CLIF-Consortiumacute-on-chronic liver failure score(CLIF-C-ACLFs)models,we assessed the predictive accuracy of the nomogram using the concordance index(C-index),and its discriminative ability using time-dependent receiver operating characteristics(td-ROC)analysis,respectively.Results:Multivariate logistic regression analysis of the development set carried out to predict mortality revealed that γ-glutamyl transpeptidase,albumin,total bilirubin,urea nitrogen,creatinine,international normalized ratio,and neutrophil-to-lymphocyte ratio were independent factors,all of which were incorporated into the new nomogram to predict the mortality of HEV-ALF patients.The area under the curve of this nomogram for mortality prediction was 0.671(95%confidence interval:0.602-0.740),which was higher than that of the MELD and CLIF-C-ACLFs models.Moreover,the td-ROC and decision curves analysis showed that both discriminative ability and threshold probabilities of the nomogram were superior to those of the MELD and CLIF-C-ACLFs models.A similar trend was observed in the validation set.Conclusions:The novel nomogram is an accurate and efficient mortality prediction method for HEV-ALF patients.展开更多
To prepare an effective immune preparation to treat hepatitis B, hens were immunized with hepatitis B vaccines, and then anti-HBV egg yolk extraction (anti-HBV EYE) was refined from egg yolk by a dialyzable method. ...To prepare an effective immune preparation to treat hepatitis B, hens were immunized with hepatitis B vaccines, and then anti-HBV egg yolk extraction (anti-HBV EYE) was refined from egg yolk by a dialyzable method. Its chemical characteristics were identified by ultraviolet spectrum, HPLC, Lowry analysis and pharmacopocia-raleted methods. The specific immunological activity was examined by leukocyte adherence inhibition (LAI) in vitro and delayed type hypersensitivity (DTH) in vivo. Anti-HBV EYE was a small dialyzable substance with molecular weight less than 12 kD containing 18 kinds of amino acids. The preparation could obviously inhibit LAI and DTH which was similar to hepatitis B virus-specific transfer factor of pig spleen. However, there were no similar effects observed in the nonspecific transfer factor (NTF) group, control egg yolk extraction (CEYE) group and hepatitis A virus (HAV) group. The results suggested that anti-HBV EYE contained hepatitis B virus-specific transfer factor (STF) and had the antigen-specific cell immune activity similar to PSHBV-TF. The STF obtained from egg yolk of the hens immunized with specific antigen, might be a potential candidate for immunoregulation in hepatitis B prevention and treatment.展开更多
The detection of circulating tumor cells(CTCs)is a crucial tool for early cancer diagnosis,prognosis,and postoperative evaluation.However,detection sensitivity remains a major challenge because CTCs are extremely rare...The detection of circulating tumor cells(CTCs)is a crucial tool for early cancer diagnosis,prognosis,and postoperative evaluation.However,detection sensitivity remains a major challenge because CTCs are extremely rare in peripheral blood.To effectively detect CTCs,octahedral Ag_(2)O nanoparticles(NPs)with high dispersibility,good biocompatibility,remarkable surface-enhanced Raman scattering(SERS)enhancement,and obvious enhancement selectivity are designed as an SERS platform.Ag_(2)O NPs with many oxygen vacancy defects are successfully synthesized,which exhibit an ultra-high SERS enhancement factor(1.98×10^(6))for 4-mercaptopyridine molecules.The remarkable SERS activity of octahedral Ag_(2)O NPs is derived from the synergistic effect of the surface defect-promoted photo-induced charge transfer(PICT)process and strong vibration coupling resonance in the Ag_(2)O-molecule SERS complex,greatly amplifying the molecular Raman scattering crosssection.The promoted PICT process is confirmed using ultraviolet-visible(UV-Vis)absorption spectroscopy,demonstrating that obvious PICT resonance occurs in Ag_(2)O SERS system under visible light.An additional growth step of SERS bioprobe is proposed by modifying the Raman signal molecules and functional biological molecules on Ag_(2)O NPs for CTC detection.The Ag_(2)O-based SERS bioprobe exhibits excellent detection specificity for different cancer cells in rabbit blood.Importantly,the high-sensitivity Ag_(2)O-based SERS bioprobe satisfies the requirement for rare CTC detection in the peripheral blood of cancer patients,and the detection limit can reach 1 cell per m L.To our knowledge,this study is the first time that a semiconductor SERS substrate has been successfully utilized in CTC detection.This work provides new insights into CTC detection and the development of novel semiconductor-based SERS platforms for cancer diagnosis.展开更多
This study examined carbonate dynamics in the northwestern South China Sea(NWSCS),an area jointly influenced by upwelling,river plumes and submarine groundwater discharge.Data were obtained from two cruises conducted ...This study examined carbonate dynamics in the northwestern South China Sea(NWSCS),an area jointly influenced by upwelling,river plumes and submarine groundwater discharge.Data were obtained from two cruises conducted in summer 2009 and 2012.In 2009,a high salinity-low temperature water mass occurred nearshore off northeastern Hainan Island,indicative of upwelling,commonly referred to as HNEU.A river plume fueled primarily by local rivers and characterized by low salinity and high temperature was observed in the NWSCS off the mainland roughly along the 30 m isobath.In 2012,coastal upwelling off northeastern Hainan Island was not detectable at the surface,but was observed at a different location off eastern Hainan Island(HEU).River plume waters in 2012 were patchily distributed,with a low salinity zone further westerly than that in 2009 and another on the mid-shelf of the NWSCS sourced from the Pearl River which reached out~250 km from the mouth of the Pearl River Estuary.In 2009,elevated dissolved inorganic carbon(DIC)and total alkalinity(TA)occurred in the coastal plume,where submarine groundwater discharge contributed DIC and TA additions of 38.9±20.5 and 42.5±22.3μmol kg^(−1),respectively,with a DIC/TA ratio of~0.92,which made a minor contribution to the variation of seawater partial pressure of CO_(2)(pCO_(2)),pH and the aragonite saturation state index(Ω_(arag)).Additionally,high surface phytoplankton production consumed DIC of 10.0±10.4μmol kg^(−1) but did not significantly affect TA,which dominated pCO_(2) drawdown in the coastal plume water and increased the pH andΩ_(arag) at surface.Submarine groundwater discharge was also observed in the region influenced by upwelling,but to a lesser degree than that impacted by coastal plume.Lower pH andΩ_(arag) and higher pCO_(2) values than in offshore waters were observed downstream of the upwelling system,attributable largely to organic matter remineralization with a DIC addition of 23.8±8.4μmol kg^(−1).In 2012,submarine groundwater discharge was not detected but high phytoplankton production dominated carbonate dynamics in the coastal plume water with a net DIC consumption of 104.2μmol kg^(−1),which markedly drew down sea surface pCO_(2) and increased pH andΩ_(arag).In the Pearl River Plume,the solubility-driven CO_(2) sink exceeded biological CO_(2) uptake,resulting in an additional decrease of pH andΩ_(arag) and increase of seawater pCO_(2).Taken together,this study demonstrated complex spatial and year-to-year variability,and the controls of the carbonate system under the joint modulations of upwelling,river plumes and submarine groundwater discharge.A first order estimate that considered the rise of atmospheric CO_(2) and seawater temperature further suggested a high risk of ocean acidification in this coastal area by the end of this century,which could be amplified under the stresses of river plumes,submarine groundwater discharge and organic matter remineralization.展开更多
基金supported by the National Key R and D Program of China(2022ZD0119902)the National Natural Science Foundation of China(52271304,51979020,52071044)+4 种基金the Top-notch Young Talents Program of China(36261402)in part by the Liaoning Revitalization Talents Program(XLYC2007188)Highlevel Talents Innovation Support Program(2022RY07,2022RQ010)the Dalian Science and Technology Innovation Fund(2022JJ12 GX034)the Postdoctoral Research Foundation of China(2022M720619)。
文摘Dear Editor, Collision avoidance is critical for safe operations of multiple autonomous surface vehicles(ASVs). It is a challenging task to design collision-free control laws to ensure safety, especially in a crowded sea environment. This letter presents a collision-free pointto-point transition strategy for multiple ASVs subject to static obstacles, dynamic obstacles and neighboring ASVs based on control barrier functions(CBFs).
基金supported by Shanghai Science and Technology Committee (No. 20DZ2201900)National Natural Science Foundation of China (No. 82072602)+1 种基金Innovation Foundation of Translational Medicine of Shanghai Jiao Tong University School of Medicine (No. TM202001)Collaborative Innovation Center for Clinical and Translational Science by Chinese Ministry of Education & Shanghai (No. CCTS-2022202 and No. CCTS-202302)。
文摘Gastrointestinal cancers are a public health problem that threatens the lives of human being. A good experimental model is a powerful tool to promote the uncovering pathogenesis and establish novel treatment methods. High-quality biomedical research requires experimental models to recapitulate the physiological and pathological states of their parental tissues as much as possible. Organoids are such experimental models. Organoids refer to small organlike cellular clusters formed by the expansion and passaging of living tissues in 3D culture medium in vitro.Organoids are highly similar to the original tissues in terms of cellular composition, cell functions, and genomic profiling. Organoids have many advantages, such as short preparation cycles, long-term storage based on cryopreservation, and reusability. In recent years, researchers carried out the establishment of organoids from gastrointestinal mucosa and cancer tissues, and accumulated valuable experiences. In order to promote effective usage and further development of organoid-related technologies in the research of gastrointestinal diseases, this study proposes a benchmark based on utilization of available experimental consumables and reagents, which are involved in the key steps such as collection and pretreatment of biospecimen, organoid construction, organoid cryopreservation and recovery, growth status evaluation, and organoid quality control. We believe that the standard for the construction and preservation of organoids derived from human gastrointestinal epithelium and cancer tissues can provide an important reference for the majority of scientific researchers.
文摘With the rapid development of wind power, the large-scale wind power integration brings a new range of issues in dispatching operation. In order to gain a better grasp of the influence caused by wind power combined to the grid, the paper first establishes the impact characteristic indexes, and then analyzes the regularity of wind power time series in different spatial and temporal scales. At last, according to the analysis results, this paper assesses the impact of time-series characteristics of wind power on power grid, such as the frequency regulation, peak load regulation, which can provide the reference for wind power optimal dispatching of Jilin Power Grid.
基金Supported by a grant from the Health Department of Jiangxi Province for Science Technical Program Foundation(No.2005-22A)
文摘Objective: The present study was designed to investigate whether quercetin exerts increasing chemosensitivity on human lung adenocarcinoma cells when quercetin combined with cisplatin (DDP) and vincristine (VCR) in vitro respectively and its possible antitumor mechanism. To provide experimental proof for clinical combination application. Methods: Using intermittent administration of high dose VCR, human lung adenocarcinoma sensitive cell line (A549/S) was induced to VCR-resistant human lung adenocarcinoma cell line (A549/VCR). MTT assay was adapted for examing the 50% inhibition (IC50) value of DDP and VCR on A549/S and A549/VCR when quercetin combined with DDP and VCR respectively. Results: IC50 of DDP on A549/S and A549/VCR was 10.18 and 12.35 mg/L, and the IC50 of VCR on the two cell lines was 1.21 and 12.77 mg/L, respectively. The resistance fold of A549/VCR on VCR and DDP was 10.55 and 1.21, respectively. When quercetin at concentration of 50, 100 and 200 μmol/L in combination with DDP and VCR respectively, the IC50 of DDP and VCR on A549/S and A549/VCR were obvious decreased (P < 0.05 - P < 0.01). Conclusion: The experiment results suggested that quercetin could increase the chemosensitivity and partly revise the resistance of A549/VCR.
基金supported in part by the National Natural Science Funds of China under Grants 5217071282 and 5210071275in part by China Postdoctoral Science Foundation under Grant 2020M683524+7 种基金in part by Nature Science Basic Research Plan in Shaanxi Province under Grant 2020JQ-631 and 2021JQ-477in part by State Key Laboratory of Electrical Insulation and Power Equipment under Grant EIPE20201in part by State Key Laboratory of Large Electric Drive System and Equipment Technology under Grant SKLLDJ012016006in part by Key Research and Development Project of ShaanXi Province under Grant 2019GY-060in part by Key Laboratory of Industrial Automation in ShaanXi Province under Grant SLGPT2019KF01-12in part by the Key R&D plan of Shaanxi Province under Grant 2021GY-282in part by Shaanxi Outstanding Youth Fund under Grant 2020JC-40in part by Key Laboratory of Power Electronic Devices and High Efficiency Power Conversion in Xi’an under Grant 2019219814SYS013CG035。
文摘Finite control set model predictive torque control(FCS-MPTC)has become increasingly prevalent for induction motors(IM)owing to its simple concept,easy incorporation of constraints and strong flexibility.In traditional FCS-MPTC speed controller design,a classical proportional integral(PI)controller is typically chosen to generate the torque reference.However,the PI controller is dependent on system parameters and sensitive to the load torque variation,which seriously affects control performance.In this paper,a model predictive torque control using sliding mode control(MPTC+SMC)for IM is proposed to enhance the robust performance of the drive system.First,the influence of the parameter mismatches for FCS-MPTC is analyzed.Second,the shortcomings of traditional PI controller are derived.Then,the proposed MPTC+SMC method is designed,and the MPTC+PI and MPTC+SMC are compared theoretically.Finally,experimental results demonstrate the correctness and effectiveness of the proposed MPTC+SMC.In comparison with MPTC+PI,MPTC+SMC has the better dynamic performance and stronger robust performance against parameter variations and load disturbance.
基金Thisre search was partially supported by the National Natural Science Foundation of China(grant 62076215)the Talent Introduction Project of Yancheng Institute of Technology under Grant No.XKR2011019.
文摘Clustering analysis plays a very important role in the field of data mining,image segmentation and pattern recognition.The method of cluster analysis is introduced to analyze NetEYun music data.In addition,different types of music data are clustered to find the commonness among the same kind of music.A music data-oriented clustering analysis method is proposed:Firstly,the audio beat period is calculated by reading the audio file data,and the emotional features of the audio are extracted;Secondly,the audio beat period is calculated by Fourier transform.Finally,a clustering algorithm is designed to obtain the clustering results of music data.
基金supported by the Cultivation Project of Shanghai Major Infectious Disease Research Base(20dz2210500)the Shanghai Key Laboratory of Emergency Prevention,Diagnosis and Treatment of Respiratory Infectious Diseases(20dz2261100)the National Natural Science Foundation of China(81671589 and 81871272).
基金the National Science and Technology Major Project for Infectious Diseases(2012ZX10002004).
文摘Background and Aims:Timely and effective assessment scoring systems for predicting the mortality of patients with hepatitis E virus-related acute liver failure(HEV-ALF)are urgently needed.The present study aimed to establish an effective nomogram for predicting the mortality of HEV-ALF patients.Methods:The nomogram was based on a cross-sectional set of 404 HEV-ALF patients who were identified and enrolled from a cohort of 650 patients with liver failure.To compare the performance with that of the model for end-stage liver disease(MELD)scoring and CLIF-Consortiumacute-on-chronic liver failure score(CLIF-C-ACLFs)models,we assessed the predictive accuracy of the nomogram using the concordance index(C-index),and its discriminative ability using time-dependent receiver operating characteristics(td-ROC)analysis,respectively.Results:Multivariate logistic regression analysis of the development set carried out to predict mortality revealed that γ-glutamyl transpeptidase,albumin,total bilirubin,urea nitrogen,creatinine,international normalized ratio,and neutrophil-to-lymphocyte ratio were independent factors,all of which were incorporated into the new nomogram to predict the mortality of HEV-ALF patients.The area under the curve of this nomogram for mortality prediction was 0.671(95%confidence interval:0.602-0.740),which was higher than that of the MELD and CLIF-C-ACLFs models.Moreover,the td-ROC and decision curves analysis showed that both discriminative ability and threshold probabilities of the nomogram were superior to those of the MELD and CLIF-C-ACLFs models.A similar trend was observed in the validation set.Conclusions:The novel nomogram is an accurate and efficient mortality prediction method for HEV-ALF patients.
文摘To prepare an effective immune preparation to treat hepatitis B, hens were immunized with hepatitis B vaccines, and then anti-HBV egg yolk extraction (anti-HBV EYE) was refined from egg yolk by a dialyzable method. Its chemical characteristics were identified by ultraviolet spectrum, HPLC, Lowry analysis and pharmacopocia-raleted methods. The specific immunological activity was examined by leukocyte adherence inhibition (LAI) in vitro and delayed type hypersensitivity (DTH) in vivo. Anti-HBV EYE was a small dialyzable substance with molecular weight less than 12 kD containing 18 kinds of amino acids. The preparation could obviously inhibit LAI and DTH which was similar to hepatitis B virus-specific transfer factor of pig spleen. However, there were no similar effects observed in the nonspecific transfer factor (NTF) group, control egg yolk extraction (CEYE) group and hepatitis A virus (HAV) group. The results suggested that anti-HBV EYE contained hepatitis B virus-specific transfer factor (STF) and had the antigen-specific cell immune activity similar to PSHBV-TF. The STF obtained from egg yolk of the hens immunized with specific antigen, might be a potential candidate for immunoregulation in hepatitis B prevention and treatment.
基金supported by the National Natural Science Foundation of China(32025021,52002380,31971292,and 51873225)Zhejiang Province Key Research Project(2019C03058)+4 种基金Strategic Priority Research Program of Chinese Academy of Sciences(XDB36000000)Zhejiang Province Financial Supporting(LQ20E020003)Natural Science Foundation of Ningbo(2019A610024)Ningbo 3315 Innovative Teams Program(2019A-14-C)STS project from the Chinese Academy of Sciences(KFJ-STS-ZDTP-061)。
文摘The detection of circulating tumor cells(CTCs)is a crucial tool for early cancer diagnosis,prognosis,and postoperative evaluation.However,detection sensitivity remains a major challenge because CTCs are extremely rare in peripheral blood.To effectively detect CTCs,octahedral Ag_(2)O nanoparticles(NPs)with high dispersibility,good biocompatibility,remarkable surface-enhanced Raman scattering(SERS)enhancement,and obvious enhancement selectivity are designed as an SERS platform.Ag_(2)O NPs with many oxygen vacancy defects are successfully synthesized,which exhibit an ultra-high SERS enhancement factor(1.98×10^(6))for 4-mercaptopyridine molecules.The remarkable SERS activity of octahedral Ag_(2)O NPs is derived from the synergistic effect of the surface defect-promoted photo-induced charge transfer(PICT)process and strong vibration coupling resonance in the Ag_(2)O-molecule SERS complex,greatly amplifying the molecular Raman scattering crosssection.The promoted PICT process is confirmed using ultraviolet-visible(UV-Vis)absorption spectroscopy,demonstrating that obvious PICT resonance occurs in Ag_(2)O SERS system under visible light.An additional growth step of SERS bioprobe is proposed by modifying the Raman signal molecules and functional biological molecules on Ag_(2)O NPs for CTC detection.The Ag_(2)O-based SERS bioprobe exhibits excellent detection specificity for different cancer cells in rabbit blood.Importantly,the high-sensitivity Ag_(2)O-based SERS bioprobe satisfies the requirement for rare CTC detection in the peripheral blood of cancer patients,and the detection limit can reach 1 cell per m L.To our knowledge,this study is the first time that a semiconductor SERS substrate has been successfully utilized in CTC detection.This work provides new insights into CTC detection and the development of novel semiconductor-based SERS platforms for cancer diagnosis.
基金funded by the National Natural Science Foundation of China(Grant Nos.42188102,41206061)the Hong Kong Research Grants Council(Grant No.T21-602/16-R).
文摘This study examined carbonate dynamics in the northwestern South China Sea(NWSCS),an area jointly influenced by upwelling,river plumes and submarine groundwater discharge.Data were obtained from two cruises conducted in summer 2009 and 2012.In 2009,a high salinity-low temperature water mass occurred nearshore off northeastern Hainan Island,indicative of upwelling,commonly referred to as HNEU.A river plume fueled primarily by local rivers and characterized by low salinity and high temperature was observed in the NWSCS off the mainland roughly along the 30 m isobath.In 2012,coastal upwelling off northeastern Hainan Island was not detectable at the surface,but was observed at a different location off eastern Hainan Island(HEU).River plume waters in 2012 were patchily distributed,with a low salinity zone further westerly than that in 2009 and another on the mid-shelf of the NWSCS sourced from the Pearl River which reached out~250 km from the mouth of the Pearl River Estuary.In 2009,elevated dissolved inorganic carbon(DIC)and total alkalinity(TA)occurred in the coastal plume,where submarine groundwater discharge contributed DIC and TA additions of 38.9±20.5 and 42.5±22.3μmol kg^(−1),respectively,with a DIC/TA ratio of~0.92,which made a minor contribution to the variation of seawater partial pressure of CO_(2)(pCO_(2)),pH and the aragonite saturation state index(Ω_(arag)).Additionally,high surface phytoplankton production consumed DIC of 10.0±10.4μmol kg^(−1) but did not significantly affect TA,which dominated pCO_(2) drawdown in the coastal plume water and increased the pH andΩ_(arag) at surface.Submarine groundwater discharge was also observed in the region influenced by upwelling,but to a lesser degree than that impacted by coastal plume.Lower pH andΩ_(arag) and higher pCO_(2) values than in offshore waters were observed downstream of the upwelling system,attributable largely to organic matter remineralization with a DIC addition of 23.8±8.4μmol kg^(−1).In 2012,submarine groundwater discharge was not detected but high phytoplankton production dominated carbonate dynamics in the coastal plume water with a net DIC consumption of 104.2μmol kg^(−1),which markedly drew down sea surface pCO_(2) and increased pH andΩ_(arag).In the Pearl River Plume,the solubility-driven CO_(2) sink exceeded biological CO_(2) uptake,resulting in an additional decrease of pH andΩ_(arag) and increase of seawater pCO_(2).Taken together,this study demonstrated complex spatial and year-to-year variability,and the controls of the carbonate system under the joint modulations of upwelling,river plumes and submarine groundwater discharge.A first order estimate that considered the rise of atmospheric CO_(2) and seawater temperature further suggested a high risk of ocean acidification in this coastal area by the end of this century,which could be amplified under the stresses of river plumes,submarine groundwater discharge and organic matter remineralization.