Given that fermentation time has significant impact on quality and flavor of soy sauce,a global understanding of the metabolic mechanism as fermentation time prolonged is essential for producing satisfactory and consi...Given that fermentation time has significant impact on quality and flavor of soy sauce,a global understanding of the metabolic mechanism as fermentation time prolonged is essential for producing satisfactory and consistent quality of traditional soy sauce.Herein,the metabolic compounds changes of soy sauce associated with fermentation time up to 10 years were comprehensively investigated by using Chinese traditional fermented soy sauce(CTFSS)as a demonstration.Results showed that formaldehyde nitrogen,total soluble nitrogen(TSN),non-salt soluble solids,amino acids,free 5’-nucleotides and volatile compounds in CTFSS changed obviously during fermentation.Specifically,glutamic acid and aspartic acid were prominent in CTFSS.Continuous decrease in content of hypoxanthine(Hx)was found from 1 M(1-month soy sauce)to7 M(7-months soy sauce).Furthermore,a significant opposite tendency for changes between some volatile compounds and amino acids was indicated that there was a transformation between these two components.Therefore,a better understanding to the influence of fermentation time on soy sauce had been proposed.As the formation and conversion of amino acids and sugars might be mainly responsible for flavor formation in CTFSS,the ratio of these two reactions rate led the metabolism to be divided into three steps,degradation,conversion and balance.展开更多
The formation of bacterial biofilms closely associates with infectious diseases.Until now,precise diagnosis and effective treatment of bacterial biofilm infections are still in great need.Herein,a novel multifunctiona...The formation of bacterial biofilms closely associates with infectious diseases.Until now,precise diagnosis and effective treatment of bacterial biofilm infections are still in great need.Herein,a novel multifunctional theranostic nanoplatform based on MnO_(2)nanosheets(MnO_(2)NSs)has been designed to achieve pH-responsive dual-mode imaging and hypoxia-relief-enhanced antimicrobial photodynamic therapy(aPDT)of bacterial biofilm infections.In this study,MnO_(2)NSs were modified with bovine serum albumin(BSA)and polyethylene glycol(PEG)and then loaded with chlorin e_(6)(Ce_(6))as photosensitizer to form MnO_(2)-BSA/PEG-Ce_(6)nanosheets(MBP-Ce_(6)NSs).After being delivered into the bacterial biofilm-infected tissues,the MBP-Ce_(6)NSs could be decomposed in acidic biofilm microenvironment and release Ce_(6)with Mn^(2+),which subsequently activate both fluorescence(FL)and magnetic resonance(MR)signals for effective dual-mode FL/MR imaging of bacterial biofilm infections.Meanwhile,MnO_(2)could catalyze the decomposing of H2O_(2)in biofilm-infected tissues into O_(2)and relieve the hypoxic condition of biofilm,which significantly enhances the efficacy of aPDT.An in vitro study showed that MBP-Ce_(6)NSs could significantly reduce the number of methicillin-resistant Staphylococcus aureus(MRSA)in biofilms after 635nm laser irradiation.Guided by FL/MR imaging,MRSA biofilm-infected mice can be efficiently treated by MBP-Ce_(6)NSs-based aPDT.Overall,MBP-Ce_(6)NSs not only possess biofilm microenvironment-responsive dual-mode FL/MR imaging ability but also have significantly enhanced aPDT efficacy by relieving the hypoxia habitat of biofilm,which provides a promising theranostic nanoplatform for bacterial biofilm infections.展开更多
In this paper,the authors consider a sparse parameter estimation problem in continuoustime linear stochastic regression models using sampling data.Based on the compressed sensing(CS)method,the authors propose a compre...In this paper,the authors consider a sparse parameter estimation problem in continuoustime linear stochastic regression models using sampling data.Based on the compressed sensing(CS)method,the authors propose a compressed least squares(LS) algorithm to deal with the challenges of parameter sparsity.At each sampling time instant,the proposed compressed LS algorithm first compresses the original high-dimensional regressor using a sensing matrix and obtains a low-dimensional LS estimate for the compressed unknown parameter.Then,the original high-dimensional sparse unknown parameter is recovered by a reconstruction method.By introducing a compressed excitation assumption and employing stochastic Lyapunov function and martingale estimate methods,the authors establish the performance analysis of the compressed LS algorithm under the condition on the sampling time interval without using independence or stationarity conditions on the system signals.At last,a simulation example is provided to verify the theoretical results by comparing the standard and the compressed LS algorithms for estimating a high-dimensional sparse unknown parameter.展开更多
Nano filler synergistic intumescent flame retardant(IFR)system is an effective way to improve the flame retardant properties of polymer.In this study,the effects of montmorillonite(MMT)on the flame retardant propertie...Nano filler synergistic intumescent flame retardant(IFR)system is an effective way to improve the flame retardant properties of polymer.In this study,the effects of montmorillonite(MMT)on the flame retardant properties of polylactic acid/layered double hydroxides(PLA/LDH)and PLA/IFR/LDH were investigated.The results show that both LDH and LDH/IFR can reduce the peak heat release rate(HRR)of PLA and prolong the combustion time of PLA;When a proportionate MMT is introduced into PLA/LDH and PLA/IFR/LDH systems,respectively,MMT will not only affect the degradation process of PLA composites during combustion,but also the PLA composites can form a more stable carbon layer during combustion,which could decrease the peak HRR and prolong combustion time of PLA composite.Furthermore,when 0.5 wt%MMT is incorporated,the peak HRR of LDH/IFR/LDH composite is reduced by 16.17%and the combustion time is prolonged by about 70 s.This study can provide an opportunity to further optimize the properties of intumescent flame retardant polymer.展开更多
As a route to improving the energy conversion of organic-inorganic hybrid-solar cells, we have tested the performance of poly(phenylene vinylene)(PPV), poly(2,5-thienylene vinylene)(PWTV) polymers and CdTe nanocrystal...As a route to improving the energy conversion of organic-inorganic hybrid-solar cells, we have tested the performance of poly(phenylene vinylene)(PPV), poly(2,5-thienylene vinylene)(PWTV) polymers and CdTe nanocrystal devices produced via aqueous-processing. It is found that small differences in the conformation of the sensitizer lead to dramatic effects on the solar cell efficiency. Using a combination of UV-Vis absorption spectroscopy and first-principles non-adiabatic molecular dynamics(NAMD) based on time-dependent density-functional theory(TDDFT), PPV is found to have a longer electron injection and recombination time despite seeming to have a better energy alignment with the substrate, which leads to a higher devices performance than PWTV. The present results shed new light on the understanding of organic-inorganic hybrid-solar cells and will trigger further experimental and theoretical investigations.展开更多
基金financially supported by the National Key Research and Development Program of China(2016YFD0401501)Shanghai Pujiang Program(18PJ1432600)。
文摘Given that fermentation time has significant impact on quality and flavor of soy sauce,a global understanding of the metabolic mechanism as fermentation time prolonged is essential for producing satisfactory and consistent quality of traditional soy sauce.Herein,the metabolic compounds changes of soy sauce associated with fermentation time up to 10 years were comprehensively investigated by using Chinese traditional fermented soy sauce(CTFSS)as a demonstration.Results showed that formaldehyde nitrogen,total soluble nitrogen(TSN),non-salt soluble solids,amino acids,free 5’-nucleotides and volatile compounds in CTFSS changed obviously during fermentation.Specifically,glutamic acid and aspartic acid were prominent in CTFSS.Continuous decrease in content of hypoxanthine(Hx)was found from 1 M(1-month soy sauce)to7 M(7-months soy sauce).Furthermore,a significant opposite tendency for changes between some volatile compounds and amino acids was indicated that there was a transformation between these two components.Therefore,a better understanding to the influence of fermentation time on soy sauce had been proposed.As the formation and conversion of amino acids and sugars might be mainly responsible for flavor formation in CTFSS,the ratio of these two reactions rate led the metabolism to be divided into three steps,degradation,conversion and balance.
基金This work was financially supported by the National Key Research and Development Program of China(2017YFA0205302)Natural Science Foundation of Jiangsu Province(BK20191382)+2 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD,YX030003)the Jiangsu Provincial Key Research and Development Program(BE2018732)the Natural Science Key Fund for Colleges and Universities in Jiangsu Province(17KJA430011).
文摘The formation of bacterial biofilms closely associates with infectious diseases.Until now,precise diagnosis and effective treatment of bacterial biofilm infections are still in great need.Herein,a novel multifunctional theranostic nanoplatform based on MnO_(2)nanosheets(MnO_(2)NSs)has been designed to achieve pH-responsive dual-mode imaging and hypoxia-relief-enhanced antimicrobial photodynamic therapy(aPDT)of bacterial biofilm infections.In this study,MnO_(2)NSs were modified with bovine serum albumin(BSA)and polyethylene glycol(PEG)and then loaded with chlorin e_(6)(Ce_(6))as photosensitizer to form MnO_(2)-BSA/PEG-Ce_(6)nanosheets(MBP-Ce_(6)NSs).After being delivered into the bacterial biofilm-infected tissues,the MBP-Ce_(6)NSs could be decomposed in acidic biofilm microenvironment and release Ce_(6)with Mn^(2+),which subsequently activate both fluorescence(FL)and magnetic resonance(MR)signals for effective dual-mode FL/MR imaging of bacterial biofilm infections.Meanwhile,MnO_(2)could catalyze the decomposing of H2O_(2)in biofilm-infected tissues into O_(2)and relieve the hypoxic condition of biofilm,which significantly enhances the efficacy of aPDT.An in vitro study showed that MBP-Ce_(6)NSs could significantly reduce the number of methicillin-resistant Staphylococcus aureus(MRSA)in biofilms after 635nm laser irradiation.Guided by FL/MR imaging,MRSA biofilm-infected mice can be efficiently treated by MBP-Ce_(6)NSs-based aPDT.Overall,MBP-Ce_(6)NSs not only possess biofilm microenvironment-responsive dual-mode FL/MR imaging ability but also have significantly enhanced aPDT efficacy by relieving the hypoxia habitat of biofilm,which provides a promising theranostic nanoplatform for bacterial biofilm infections.
基金supported by the Major Key Project of Peng Cheng Laboratory under Grant No.PCL2023AS1-2Project funded by China Postdoctoral Science Foundation under Grant Nos.2022M722926 and2023T160605。
文摘In this paper,the authors consider a sparse parameter estimation problem in continuoustime linear stochastic regression models using sampling data.Based on the compressed sensing(CS)method,the authors propose a compressed least squares(LS) algorithm to deal with the challenges of parameter sparsity.At each sampling time instant,the proposed compressed LS algorithm first compresses the original high-dimensional regressor using a sensing matrix and obtains a low-dimensional LS estimate for the compressed unknown parameter.Then,the original high-dimensional sparse unknown parameter is recovered by a reconstruction method.By introducing a compressed excitation assumption and employing stochastic Lyapunov function and martingale estimate methods,the authors establish the performance analysis of the compressed LS algorithm under the condition on the sampling time interval without using independence or stationarity conditions on the system signals.At last,a simulation example is provided to verify the theoretical results by comparing the standard and the compressed LS algorithms for estimating a high-dimensional sparse unknown parameter.
基金State Key Laboratory of Environmentfriendly Energy Materials,Southwest University of Science and Technology(20FKSY15,19FKSY0110)Longshan Academic Talent Research Supporting Program of SWUST(17LZX636,18LZX629).
文摘Nano filler synergistic intumescent flame retardant(IFR)system is an effective way to improve the flame retardant properties of polymer.In this study,the effects of montmorillonite(MMT)on the flame retardant properties of polylactic acid/layered double hydroxides(PLA/LDH)and PLA/IFR/LDH were investigated.The results show that both LDH and LDH/IFR can reduce the peak heat release rate(HRR)of PLA and prolong the combustion time of PLA;When a proportionate MMT is introduced into PLA/LDH and PLA/IFR/LDH systems,respectively,MMT will not only affect the degradation process of PLA composites during combustion,but also the PLA composites can form a more stable carbon layer during combustion,which could decrease the peak HRR and prolong combustion time of PLA composite.Furthermore,when 0.5 wt%MMT is incorporated,the peak HRR of LDH/IFR/LDH composite is reduced by 16.17%and the combustion time is prolonged by about 70 s.This study can provide an opportunity to further optimize the properties of intumescent flame retardant polymer.
基金supported by the National Natural Science Foundation of China(51433003)the National Basic Research Program of China(2014CB643503)
文摘As a route to improving the energy conversion of organic-inorganic hybrid-solar cells, we have tested the performance of poly(phenylene vinylene)(PPV), poly(2,5-thienylene vinylene)(PWTV) polymers and CdTe nanocrystal devices produced via aqueous-processing. It is found that small differences in the conformation of the sensitizer lead to dramatic effects on the solar cell efficiency. Using a combination of UV-Vis absorption spectroscopy and first-principles non-adiabatic molecular dynamics(NAMD) based on time-dependent density-functional theory(TDDFT), PPV is found to have a longer electron injection and recombination time despite seeming to have a better energy alignment with the substrate, which leads to a higher devices performance than PWTV. The present results shed new light on the understanding of organic-inorganic hybrid-solar cells and will trigger further experimental and theoretical investigations.
