Background: Hemodynamic instability is common in critical patients and not all patients respond to fluid challenge, so we need accurate and rapid hemodynamic techniques to help the clinicians to guide fluid treatment....Background: Hemodynamic instability is common in critical patients and not all patients respond to fluid challenge, so we need accurate and rapid hemodynamic techniques to help the clinicians to guide fluid treatment. Numerous hemodynamic techniques have been used to predict fluid responsiveness till now. Transthoracic echocardiography (TTE) appears to have the ability to predict fluid responsiveness, but there is no consensus on whether it can be used by passive leg raising (PLR). Methods: We performed a literature search using MEDLINE (source PubMed, from 1947), EMBASE (from 1974) and the Cochrane Database of Systematic Reviews for prospective studies with no restrictions. Pooled effect estimates were obtained by using random-effects meta-analysis. Results: 7 prospective studies involving 261 patients and 285 boluses were identified. The pooled sensitivity and specificity of TTE are 86% (79% - 91%) and 90% (83% - 94%), respectively. The summary receiver operating characteristic (sROC) curve shows an optimum joint sensitivity and specificity of 0.88, with area under the sROC curve (AUC) of 0.94. The result of diagnostic odds ratio (DOR) is 50.62 (95% confidence interval [CI]: 23.70 - 108.12). The results of positive likelihood ratio (+LR) and negative likelihood ratio (?LR) are 7.07 (95% CI: 4.39 - 11.38) and 0.19 (95% CI: 0.13 - 0.28), which indicated strong diagnostic evidence. Conclusions: TTE is a repeatable and reliable noninvasive tool to predict fluid responsiveness in the critically ill during PLR with good test performance. This meta-analysis brings evidence to employ well-trained clinician-echocardiographers to assess patients’ volume statue via TTE to benefit daily work in intensive care units (ICUs).展开更多
Objective: To analyze the accuracy and specificity of recent studies to compare the ability of predicting fluid responsiveness with Passive Leg Raising (PLR) by using invasive or non-invasive techniques during passive...Objective: To analyze the accuracy and specificity of recent studies to compare the ability of predicting fluid responsiveness with Passive Leg Raising (PLR) by using invasive or non-invasive techniques during passive leg raising. Data Sources: MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews were systematically searched. Study Selection: Clinical trials that reported the sensitivity, specificity and area under the receiver operating characteristic curve (AUC) between the responder and non-responder induced by passive leg raising and Volume Expansion (VE) in critical ill patients were selected. 246 studies were screened, 14 studies were included for data extraction, which met our inclusion criteria. Data Extraction: Data were abstracted on study characteristics, patient population, type and amount of VE, time of VE, definition of responders, position, techniques used for measuring hemodynamic change, number and percentage of responders, the correlation coefficient, sensitivity, specificity, best threshold and area under the ROC curve (AUC). Meta-analytic techniques were used to summarize the data. Data Synthesis: A total of 524 critical ill patients from 14 studies were analyzed. Data are reported as point estimate (95% confidence intervals). The pooled sensitivity and specificity of invasive techniques were 80% (73% - 85%) and 89% (84% - 93%) respectively with the area under the sROC of 0.94. While, the pooled sensitivity and specificity of non-invasive techniques were 88% (84% - 92%) and 91% (86% - 94%) respectively with the area under the sROC of 0.95. The pooled DOR of invasive techniques was 32.2 (13.6 - 76.8), which was much lower than that of non-invasive techniques with the value of 64.3 (33.9 - 121.7). Conclusions: The hemodynamic indexes changes induced by PLR could reliably predict fluid responsiveness. Non-invasive hemodynamic techniques with their accuracy and safety can benefit the daily work in ICUs. Because the number of patients included in the present trials was small, further studies should be undertaken to confirm these findings.展开更多
The efficient separation of water-in-oil emulsion is of significance in environment and energy filed,and it has become a world-wide challenge.Herein,we have presented a one-step,facile and low-cost approach to prepare...The efficient separation of water-in-oil emulsion is of significance in environment and energy filed,and it has become a world-wide challenge.Herein,we have presented a one-step,facile and low-cost approach to prepare superhydrophobic sands for efficient separation of water-in-oil emulsion.The as-prepared sand layers possessed a water contact angle higher than 151°,demonstrating their superior superhydrophobic property.Besides,the as-prepared sand layers could separate water-in-emulsions with separation efficiency up to 99.7%,which is superior to both traditional and superwettable filtration membranes.The effect of thickness of sand layer on separation performance was also investigated.The results showed that the filtration flux decreased with the increased of filtration thickness while the separation efficiency increased.The as-prepared sand layer proposed by this study is a processing candidate for separating water-in-oil emulsion in practical industry.Additionally,the as-prepared superhydrophobic sand fabrication method also provides an alternative for desert water storage.展开更多
To objectively classify and evaluate the strong aroma base liquors(SABLs)of different grades,solid-phase microextraction-mass spectrometry(SPME-MS)combined with chemometrics were used.Results showed that SPME-MS combi...To objectively classify and evaluate the strong aroma base liquors(SABLs)of different grades,solid-phase microextraction-mass spectrometry(SPME-MS)combined with chemometrics were used.Results showed that SPME-MS combined with a back-propagation artificial neural network(BPANN)method yielded almost the same recognition performance compared to linear discriminant analysis(LDA)in distinguishing different grades of SABL,with 84%recognition rate for the test set.Partial least squares(PLS),successive projection algorithm partial least squares(SPA-PLS)model,and competitive adaptive reweighed samplingpartial least squares(CARS-PLS)were established for the prediction of the four esters in the SABL.CARS-PLS model showed a greater advantage in the quantitative analysis of ethyl acetate,ethyl butyrate,ethyl caproate,and ethyl lactate.These results corroborated the hypothesis that SPME-MS combined with chemometrics can effectively achieve an accurate determination of different grades of SABL and prediction performance of esters.展开更多
CO_(2)+O_(2) in-situ leaching(ISL)of sandstonetype uranium ore represents the third generation of solution mining in China.In this study,reactive transport modeling of the interaction between hydrodynamic and geochemi...CO_(2)+O_(2) in-situ leaching(ISL)of sandstonetype uranium ore represents the third generation of solution mining in China.In this study,reactive transport modeling of the interaction between hydrodynamic and geochemical reactions is performed to enable better prediction and regulation of the CO_(2)+O_(2) in-situ leaching process of uranium.Geochemical reactions between mining solutions and rock,and the kinetic uranium dissolution controlled by O_(2)(aq)and bicarbonate(HCO_(3)-)are considered in the CO_(2)+O_(2) ISL reactive transport model of a typical sandstone-hosted uranium ore deposit in northern China.The reactive leaching of uranium is most sensitive to the spatial distribution of the mineralogical properties of the uranium deposit.Stochastic geostatistical models are used to represent the uncertainty on the spatial distribution of mineral grades.A Monte Carlo analysis was also performed to simulate the uranium production variability over an entire set of geostatistical realizations.The ISL stochastic simulation performed with the selected geostatistical realizations approximates the uranium production variability well.The simulation results of the ISL reactive transport model show that the extent of the uranium plume is highly dependent on mineralogical heterogeneity.The uncertainty analysis suggests the effect of uranium grade heterogeneity was found to be important to improve the accurate capture of the uncertainty.This study provides guidance for the accurate simulation and dynamic regulation of the CO_(2)+O_(2) leaching process of uranium at the scale of large mining areas.展开更多
VX is a highly toxic organophosphorus nerve agent that the Chemical Weapons Convention classifies as a Schedule 1. In our previous study, we developed a method for detecting organophosphorus compounds using peptide se...VX is a highly toxic organophosphorus nerve agent that the Chemical Weapons Convention classifies as a Schedule 1. In our previous study, we developed a method for detecting organophosphorus compounds using peptide self-assembly. Nevertheless, the self-assembly mechanisms of peptides that bind organophosphorus and the roles of each peptide residue remain elusive, restricting the design and application of peptide materials. Here, we use a multi-scale computational combined with experimental approach to illustrate the self-assembly mechanism of peptide-bound VX and the roles played by residues in different peptide sequences. We calculated that the self-assembly of peptides was accelerated after adding VX, and the final size of assembled nanofibers was larger than the original one, aligning with experimental findings. The atomic scale details offered by our approach enabled us to clarify the connection between the peptide sequences and nanostructures formation, as well as the contribution of various residues in binding VX and assembly process. Our investigation revealed a tight correlation between the number of Tyrosine residues and morphology of the assembly. These results indicate a self-assembly mechanism of peptide and VX, which can be used to design functional peptides for binding and hydrolyzing other organophosphorus nerve agents for detoxification and biomedical applications.展开更多
To the Editor:Coronavirus disease 2019(COVID-19)has evolved into a global pandemic,with over 700 million confirmed cases worldwide and still mounting.^([1])The clinical impact of this pandemic is immense,given the wid...To the Editor:Coronavirus disease 2019(COVID-19)has evolved into a global pandemic,with over 700 million confirmed cases worldwide and still mounting.^([1])The clinical impact of this pandemic is immense,given the wide spectrum of disease manifestation,ranging from mild respiratory symptoms to severe pulmonary infections.Identifying high-risk individuals,especially during their initial encounters in clinics and hospital emergency services,is crucial to provide timely effective treatment.Therefore,the timely risk stratification of COVID-19 patients in the emergency room can greatly benefit both infected individuals and healthcare professionals.^([2])This study aims to identify features of serious COVID-19 infection at presentation that may lead to mortality of the patients.展开更多
Nucleotide-binding and oligomerization domain(NOD)-like receptors(NLRs)are evolutionarily conserved intracellular pattern recognition receptors(PRRs)that sense microbial and danger signals,trigger immediate host defen...Nucleotide-binding and oligomerization domain(NOD)-like receptors(NLRs)are evolutionarily conserved intracellular pattern recognition receptors(PRRs)that sense microbial and danger signals,trigger immediate host defenses,and prime the adaptive immune response for long-lasting protection[1].In humans,22 known NLRs exist,and mutations in NLR family genes are associated with a wide range of inflammatory and autoimmune conditions,including hereditary periodic fever syndromes,Crohn’s disease,Blau’s syndrome,infantile enterocolitis,multiple sclerosis,and asthma[2,3].展开更多
Currently,the incidence and fatality rate of SARS-CoV-2 remain continually high worldwide.COVID-19 patients infected with SARS-CoV-2 exhibited decreased type I interferon(IFN-I)signal,along with limited activation of ...Currently,the incidence and fatality rate of SARS-CoV-2 remain continually high worldwide.COVID-19 patients infected with SARS-CoV-2 exhibited decreased type I interferon(IFN-I)signal,along with limited activation of antiviral immune responses as well as enhanced viral infectivity.Dramatic progresses have been made in revealing the multiple strategies employed by SARS-CoV-2 in impairing canonical RNA sensing pathways.However,it remains to be determined about the SARS-CoV-2 antagonism of cGAS-mediated activation of IFN responses during infection.In the current study,we figure out that SARS-CoV-2 infection leads to the accumulation of released mitochondria DNA(mtDNA),which in turn triggers cGAS to activate IFN-I signaling.As countermeasures,SARS-CoV-2 nucleocapsid(N)protein restricts the DNA recognition capacity of cGAS to impair cGAS-induced IFN-I signaling.Mechanically,N protein disrupts the assembly of cGAS with its co-factor G3BP1 by undergoing DNA-induced liquid-liquid phase separation(LLPS),subsequently impairs the double-strand DNA(dsDNA)detection ability of cGAS.Taken together,our findings unravel a novel antagonistic strategy by which SARS-CoV-2 reduces DNA-triggered IFN-I pathway through interfering with cGAS-DNA phase separation.展开更多
The near-Earth(within~100 pc)supernova explosions in the past several million years can cause the global deposition of radioactive elements(e.g.,60Fe)on Earth.The remnants of such supernovae are too old to be easily i...The near-Earth(within~100 pc)supernova explosions in the past several million years can cause the global deposition of radioactive elements(e.g.,60Fe)on Earth.The remnants of such supernovae are too old to be easily identified.It is therefore of great interest to search for million-year-old near-Earth neutron stars or black holes,the products of supernovae.However,neutron stars and black holes are challenging to find even in our Solar neighbourhood if they are not radio pulsars or X-ray/γ-ray emitters.Here we report the discovery of one of the nearest(127.7±0.3 pc)neutron star candidates in a detached single-lined spectroscopic binary LAMOST J235456.73+335625.9(hereafter J2354).Utilizing the time-resolved ground-based spectroscopy and space photometry,we find that J2354 hosts an unseen compact object with M_(inv)being 1.4-1.6 M_(⊙).The follow-up Swift ultraviolet(UV)and X-ray observations suggest that the UV and X-ray emission is produced by the visible star rather than the compact object.Hence,J2354 probably harbours a neutron star rather than a hot ultramassive white dwarf.Two-hour exceptionally sensitive radio follow-up observations with Five-hundred-meter Aperture Spherical radio Telescope fail to reveal any pulsating radio signals at the 6σflux upper limit of 12.5μJy.Therefore,the neutron star candidate in J2354 can only be revealed via our time-resolved observations.Interestingly,the distance between J2354 and our Earth can be as close as~50 pc around 2.5 million years(Myrs)ago,as revealed by the Gaia kinematics.Our discovery demonstrates a promising way to unveil the hidden near-Earth neutron stars in binaries by exploring the optical time domain,thereby facilitating understanding of the metal-enrichment history in our Solar neighbourhood.展开更多
An experimental apparatus has been built to measure the flammability limits of combustible gases based on Chinesenational standard GB/T 12474-90. The flammability limits of four binary mixtures of R161/R134a,R152a/R13...An experimental apparatus has been built to measure the flammability limits of combustible gases based on Chinesenational standard GB/T 12474-90. The flammability limits of four binary mixtures of R161/R134a,R152a/R134a, R161/N2 and R152a/N2 were measured with this apparatus at atmospheric pressure and ambienttemperature. The fuel inertization points (FIP) of these mixtures can be found from the envelopes. Comparisonswere made with the literature data; good agreement for most measurements was obtained. R134a was found tohave a better dilution effect than nitrogen in reducing the flammability of hydrofluorocarbons.展开更多
Heat transfer coefficients in nucleate boiling on a smooth flat surface were measured for pure fluids of R-134a, propane, isobutane and their binary mixtures at different pressure from 0.1 to 0.6 MPa. Series of experi...Heat transfer coefficients in nucleate boiling on a smooth flat surface were measured for pure fluids of R-134a, propane, isobutane and their binary mixtures at different pressure from 0.1 to 0.6 MPa. Series of experiments with different heat flux and mixture concentrations were carried out. The influences of pressure and heat flux on the heat transfer coefficient for different pure fluids were studied. Isobutane and propane were used to make up binary mixtures. Compared to the pure components, binary mixtures show lower heat transfer coefficients. This reduction was more pronounced as the heat flux increasing. Several heat transfer correlations are obtained for different pure refrigerants and their binary mixtures.展开更多
We demonstrate a facile and effective approach to significantly improve the photoluminescence of bulk MoS2 via laser thinning followed by gold particle decoration. Upon laser thinning of exfoliated bulk MoSz photolumi...We demonstrate a facile and effective approach to significantly improve the photoluminescence of bulk MoS2 via laser thinning followed by gold particle decoration. Upon laser thinning of exfoliated bulk MoSz photoluminescence emerges from the laser-thinned region. After further treatment with an AuCl3 solution, gold particles self-assemble on the laser-thinned region and thick edges, further increasing the fluorescence of bulk MoS2 28 times and the Raman response 3 times. Such fluorescence enhancement can be attributed to both surface plasmon resonance and p-type doping induced by gold particles. The combination of laser thinning and AuCl3 treatment enables the functionalization of bulk MoS2 for optoelectronic applications. It can also provide a viable strategy for mask-free and area-selective p-type doping on single MoS2 flakes.展开更多
HBV infection initiates hepatitis B and promotes liver cirrhosis and hepatocellular carcinoma.IFN-α is commonly used in hepatitis B therapy,but how it inhibits HBV is not fully understood.We screened 285 human interf...HBV infection initiates hepatitis B and promotes liver cirrhosis and hepatocellular carcinoma.IFN-α is commonly used in hepatitis B therapy,but how it inhibits HBV is not fully understood.We screened 285 human interferon-stimulated genes(ISGs)for anti-HBV activity using a cell-based assay,which revealed several anti-HBV ISGs.Among these ISGs,SAMD4A was the strongest suppressor of HBV replication.We found the binding site of SAMD4A in HBV RNA,which was a previously unidentified Smaug recognition region(SRE)sequence conserved in HBV variants.SAMD4A binds to the SRE site in viral RNA to trigger its degradation.The SAM domain in SAMD4A is critical for RNA binding and the C-terminal domain of SAMD4A is required for SAMD4A anti-HBV function.Human SAMD4B is a homolog of human SAMD4A but is not an ISG,and the murine genome encodes SAMD4.All these SAMD4 proteins suppressed HBV replication when overexpressed in vitro and in vivo.We also showed that knocking out the Samd4 gene in hepatocytes led to a higher level of HBV replication in mice and AAV-delivered SAMD4A expression reduced the virus titer in HBVproducing transgenic mice.In addition,a database analysis revealed a negative correlation between the levels of SAMD4A/B and HBV in patients.Our data suggest that SAMD4A is an important anti-HBV ISG for use in IFN therapy of hepatitis B and that the levels of SAMD4A/B expression are related to HBV sensitivity in humans.展开更多
The role of the p38 signaling pathway in the innate and adaptive immune responses has been well documented,especially in inflammatory cytokine production by dendritic cells(DCs).However,whether the p38 signaling pathw...The role of the p38 signaling pathway in the innate and adaptive immune responses has been well documented,especially in inflammatory cytokine production by dendritic cells(DCs).However,whether the p38 signaling pathway affects the important antigen(Ag)presentation function of DCs remains largely unknown.In this study,we reported that the deletion of p38αresulted in an impaired cross-presentation ability of CD8^(+) conventional DCs(cDCs)and a reduction in the direct presentation ability of CD8−cDCs ex vivo.Further study revealed that p38αhad a crucial role in Ag processing by CD8^(+) cDCs but did not affect the Ag uptake or co-stimulation of T cells.Moreover,p38αdeficiency led to reduced cross-priming of T cells in vivo.The production of the IL-12p40 and IL-12p70 cytokines by p38α-deficient cDCs was also significantly reduced.Our study identified a new role for p38αin modulating the important antigen cross-presentation function of DCs.展开更多
Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),is characterized by a strong production of inflammatory cytokines such as TNF and IL-6,which underlie the severi...Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),is characterized by a strong production of inflammatory cytokines such as TNF and IL-6,which underlie the severity of the disease.However,the molecular mechanisms responsible for such a strong immune response remains unclear.Here,utilizing targeted tandem mass spectrometry to analyze serum metabolome and lipidome in COVID-19 patients at different temporal stages,we identified that 611 metabolites(of 1,039)were significantly altered in COVID-19 patients.Among them,two metabolites,agmatine and putrescine,were prominently elevated in the serum of patients;and 2-quinolinecarboxylate was changed in a biphasic manner,elevated during early COVID-19 infection but levelled off.When tested in mouse embryonic fibroblasts(MEFs)and macrophages,these 3 metabolites were found to activate the NF-κB pathway that plays a pivotal role in governing cytokine production.Importantly,these metabolites were each able to cause strong increase of TNF and IL-6 levels when administered to wildtype mice,but not in the mice lacking NF-κB.Intriguingly,these metabolites have little effects on the activation of interferon regulatory factors(IRFs)for the production of type I interferons(IFNs)for antiviral defenses.These data suggest that circulating metabolites resulting from COVID-19 infection may act as effectors to elicit the peculiar systemic inflammatory responses,exhibiting severely strong proinflammatory cytokine production with limited induction of the interferons.Our study may provide a rationale for development of drugs to alleviate inflammation in COVID-19 patients.展开更多
Accurate modeling of the solubility behavior of CO_2 in the aqueous alkanolamine solutions is important to design and optimization of equipment and process. In this work, the thermodynamics of CO_2 in aqueous solution...Accurate modeling of the solubility behavior of CO_2 in the aqueous alkanolamine solutions is important to design and optimization of equipment and process. In this work, the thermodynamics of CO_2 in aqueous solution of N-methyldiethanolamine(MDEA) and piperazine(PZ) is studied by the electrolyte non-random two liquids(NRTL) model. The chemical equilibrium constants are calculated from the free Gibbs energy of formation, and the Henry's constants of CO_2 in MDEA and PZ are regressed to revise the value in the pure water. New experimental data from literatures are added to the regression process. Therefore, this model should provide a comprehensive thermodynamic representation for the quaternary system with broader ranges and more accurate predictions than previous work. Model results are compared to the experimental vapor-liquid equilibrium(VLE), speciation and heat of absorption data, which show that the model can predict the experimental data with reasonable accuracy.展开更多
文摘Background: Hemodynamic instability is common in critical patients and not all patients respond to fluid challenge, so we need accurate and rapid hemodynamic techniques to help the clinicians to guide fluid treatment. Numerous hemodynamic techniques have been used to predict fluid responsiveness till now. Transthoracic echocardiography (TTE) appears to have the ability to predict fluid responsiveness, but there is no consensus on whether it can be used by passive leg raising (PLR). Methods: We performed a literature search using MEDLINE (source PubMed, from 1947), EMBASE (from 1974) and the Cochrane Database of Systematic Reviews for prospective studies with no restrictions. Pooled effect estimates were obtained by using random-effects meta-analysis. Results: 7 prospective studies involving 261 patients and 285 boluses were identified. The pooled sensitivity and specificity of TTE are 86% (79% - 91%) and 90% (83% - 94%), respectively. The summary receiver operating characteristic (sROC) curve shows an optimum joint sensitivity and specificity of 0.88, with area under the sROC curve (AUC) of 0.94. The result of diagnostic odds ratio (DOR) is 50.62 (95% confidence interval [CI]: 23.70 - 108.12). The results of positive likelihood ratio (+LR) and negative likelihood ratio (?LR) are 7.07 (95% CI: 4.39 - 11.38) and 0.19 (95% CI: 0.13 - 0.28), which indicated strong diagnostic evidence. Conclusions: TTE is a repeatable and reliable noninvasive tool to predict fluid responsiveness in the critically ill during PLR with good test performance. This meta-analysis brings evidence to employ well-trained clinician-echocardiographers to assess patients’ volume statue via TTE to benefit daily work in intensive care units (ICUs).
文摘Objective: To analyze the accuracy and specificity of recent studies to compare the ability of predicting fluid responsiveness with Passive Leg Raising (PLR) by using invasive or non-invasive techniques during passive leg raising. Data Sources: MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews were systematically searched. Study Selection: Clinical trials that reported the sensitivity, specificity and area under the receiver operating characteristic curve (AUC) between the responder and non-responder induced by passive leg raising and Volume Expansion (VE) in critical ill patients were selected. 246 studies were screened, 14 studies were included for data extraction, which met our inclusion criteria. Data Extraction: Data were abstracted on study characteristics, patient population, type and amount of VE, time of VE, definition of responders, position, techniques used for measuring hemodynamic change, number and percentage of responders, the correlation coefficient, sensitivity, specificity, best threshold and area under the ROC curve (AUC). Meta-analytic techniques were used to summarize the data. Data Synthesis: A total of 524 critical ill patients from 14 studies were analyzed. Data are reported as point estimate (95% confidence intervals). The pooled sensitivity and specificity of invasive techniques were 80% (73% - 85%) and 89% (84% - 93%) respectively with the area under the sROC of 0.94. While, the pooled sensitivity and specificity of non-invasive techniques were 88% (84% - 92%) and 91% (86% - 94%) respectively with the area under the sROC of 0.95. The pooled DOR of invasive techniques was 32.2 (13.6 - 76.8), which was much lower than that of non-invasive techniques with the value of 64.3 (33.9 - 121.7). Conclusions: The hemodynamic indexes changes induced by PLR could reliably predict fluid responsiveness. Non-invasive hemodynamic techniques with their accuracy and safety can benefit the daily work in ICUs. Because the number of patients included in the present trials was small, further studies should be undertaken to confirm these findings.
基金supported by the Northeast Petroleum University Youth Science Foundation of China (Grant No. 15071120619)Tribology Science Fund of State Key Laboratory of Tribology (No. SKLTKF19B05)
文摘The efficient separation of water-in-oil emulsion is of significance in environment and energy filed,and it has become a world-wide challenge.Herein,we have presented a one-step,facile and low-cost approach to prepare superhydrophobic sands for efficient separation of water-in-oil emulsion.The as-prepared sand layers possessed a water contact angle higher than 151°,demonstrating their superior superhydrophobic property.Besides,the as-prepared sand layers could separate water-in-emulsions with separation efficiency up to 99.7%,which is superior to both traditional and superwettable filtration membranes.The effect of thickness of sand layer on separation performance was also investigated.The results showed that the filtration flux decreased with the increased of filtration thickness while the separation efficiency increased.The as-prepared sand layer proposed by this study is a processing candidate for separating water-in-oil emulsion in practical industry.Additionally,the as-prepared superhydrophobic sand fabrication method also provides an alternative for desert water storage.
基金The study was supported by the Key Research and Development Program of Jiangsu Province(BE2020312)National Natural Science Foundation of China(31671844)+2 种基金Open Project of National Engineering Laboratory for Agri-product Quality Traceability(AQT-2019-YB7)Science Foundation for Postdoctoral in Jiangsu Province(1501100C)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘To objectively classify and evaluate the strong aroma base liquors(SABLs)of different grades,solid-phase microextraction-mass spectrometry(SPME-MS)combined with chemometrics were used.Results showed that SPME-MS combined with a back-propagation artificial neural network(BPANN)method yielded almost the same recognition performance compared to linear discriminant analysis(LDA)in distinguishing different grades of SABL,with 84%recognition rate for the test set.Partial least squares(PLS),successive projection algorithm partial least squares(SPA-PLS)model,and competitive adaptive reweighed samplingpartial least squares(CARS-PLS)were established for the prediction of the four esters in the SABL.CARS-PLS model showed a greater advantage in the quantitative analysis of ethyl acetate,ethyl butyrate,ethyl caproate,and ethyl lactate.These results corroborated the hypothesis that SPME-MS combined with chemometrics can effectively achieve an accurate determination of different grades of SABL and prediction performance of esters.
基金jointly supported by the National Key Research and Development Program of China(No.2019YFC1804304)the National Natural Science Foundation of China(Nos.2167212,41772254)。
文摘CO_(2)+O_(2) in-situ leaching(ISL)of sandstonetype uranium ore represents the third generation of solution mining in China.In this study,reactive transport modeling of the interaction between hydrodynamic and geochemical reactions is performed to enable better prediction and regulation of the CO_(2)+O_(2) in-situ leaching process of uranium.Geochemical reactions between mining solutions and rock,and the kinetic uranium dissolution controlled by O_(2)(aq)and bicarbonate(HCO_(3)-)are considered in the CO_(2)+O_(2) ISL reactive transport model of a typical sandstone-hosted uranium ore deposit in northern China.The reactive leaching of uranium is most sensitive to the spatial distribution of the mineralogical properties of the uranium deposit.Stochastic geostatistical models are used to represent the uncertainty on the spatial distribution of mineral grades.A Monte Carlo analysis was also performed to simulate the uranium production variability over an entire set of geostatistical realizations.The ISL stochastic simulation performed with the selected geostatistical realizations approximates the uranium production variability well.The simulation results of the ISL reactive transport model show that the extent of the uranium plume is highly dependent on mineralogical heterogeneity.The uncertainty analysis suggests the effect of uranium grade heterogeneity was found to be important to improve the accurate capture of the uncertainty.This study provides guidance for the accurate simulation and dynamic regulation of the CO_(2)+O_(2) leaching process of uranium at the scale of large mining areas.
基金supported by the National Key R&D Program of China(No.2020YFF0305002)the Project program of Tianjin Key Laboratory of Food Quality and Health,Tianjin University of Science and Technology(No.TJS202102).
文摘VX is a highly toxic organophosphorus nerve agent that the Chemical Weapons Convention classifies as a Schedule 1. In our previous study, we developed a method for detecting organophosphorus compounds using peptide self-assembly. Nevertheless, the self-assembly mechanisms of peptides that bind organophosphorus and the roles of each peptide residue remain elusive, restricting the design and application of peptide materials. Here, we use a multi-scale computational combined with experimental approach to illustrate the self-assembly mechanism of peptide-bound VX and the roles played by residues in different peptide sequences. We calculated that the self-assembly of peptides was accelerated after adding VX, and the final size of assembled nanofibers was larger than the original one, aligning with experimental findings. The atomic scale details offered by our approach enabled us to clarify the connection between the peptide sequences and nanostructures formation, as well as the contribution of various residues in binding VX and assembly process. Our investigation revealed a tight correlation between the number of Tyrosine residues and morphology of the assembly. These results indicate a self-assembly mechanism of peptide and VX, which can be used to design functional peptides for binding and hydrolyzing other organophosphorus nerve agents for detoxification and biomedical applications.
基金supported by the grant from Guangdong Provincial Key R&D Program for COVID-19(No.232020012620600001)
文摘To the Editor:Coronavirus disease 2019(COVID-19)has evolved into a global pandemic,with over 700 million confirmed cases worldwide and still mounting.^([1])The clinical impact of this pandemic is immense,given the wide spectrum of disease manifestation,ranging from mild respiratory symptoms to severe pulmonary infections.Identifying high-risk individuals,especially during their initial encounters in clinics and hospital emergency services,is crucial to provide timely effective treatment.Therefore,the timely risk stratification of COVID-19 patients in the emergency room can greatly benefit both infected individuals and healthcare professionals.^([2])This study aims to identify features of serious COVID-19 infection at presentation that may lead to mortality of the patients.
基金National Natural Science Foundation of China(82388201 to JH,32170751 to Z-HY)Fundamental Research Funds for the Central Universities(226-2024-00015 to XW)+3 种基金National Key R&D Program of China(2020YFA0803500 to JH)CAMS Innovation Fund for Medical Science(2019-I2M-5-062 to JH)Fujian Province Central to Local Science and Technology Development Special Program(No.2022L3079 to JH)Fu-Xia-Quan Zi-Chuang District Cooperation Program(No.3502ZCQXT2022003 to JH).
文摘Nucleotide-binding and oligomerization domain(NOD)-like receptors(NLRs)are evolutionarily conserved intracellular pattern recognition receptors(PRRs)that sense microbial and danger signals,trigger immediate host defenses,and prime the adaptive immune response for long-lasting protection[1].In humans,22 known NLRs exist,and mutations in NLR family genes are associated with a wide range of inflammatory and autoimmune conditions,including hereditary periodic fever syndromes,Crohn’s disease,Blau’s syndrome,infantile enterocolitis,multiple sclerosis,and asthma[2,3].
基金supported by the National Key R&D Program of China (2020YFA0908700)Guangdong Provincial Key R&D Program for Covid 19 (232020012620600001)+4 种基金National Natural Science Foundation of China (82025001,31970700,32170876)Guangdong Basic and Applied Basic Research Foundation (2020B1515120090)Natural Science Foundation of Guangdong Province,China (2021A1515012179)Guangdong Clinical Research Center for Critical Care Medicine (2020B1111170005)the Sun Yat‑sen University Clinical Research Program 5010 (2019002).
文摘Currently,the incidence and fatality rate of SARS-CoV-2 remain continually high worldwide.COVID-19 patients infected with SARS-CoV-2 exhibited decreased type I interferon(IFN-I)signal,along with limited activation of antiviral immune responses as well as enhanced viral infectivity.Dramatic progresses have been made in revealing the multiple strategies employed by SARS-CoV-2 in impairing canonical RNA sensing pathways.However,it remains to be determined about the SARS-CoV-2 antagonism of cGAS-mediated activation of IFN responses during infection.In the current study,we figure out that SARS-CoV-2 infection leads to the accumulation of released mitochondria DNA(mtDNA),which in turn triggers cGAS to activate IFN-I signaling.As countermeasures,SARS-CoV-2 nucleocapsid(N)protein restricts the DNA recognition capacity of cGAS to impair cGAS-induced IFN-I signaling.Mechanically,N protein disrupts the assembly of cGAS with its co-factor G3BP1 by undergoing DNA-induced liquid-liquid phase separation(LLPS),subsequently impairs the double-strand DNA(dsDNA)detection ability of cGAS.Taken together,our findings unravel a novel antagonistic strategy by which SARS-CoV-2 reduces DNA-triggered IFN-I pathway through interfering with cGAS-DNA phase separation.
基金supported by the National Key R&D Program of China(Grant No.2021YFA1600401)the National Natural Science Foundation of China(NSFC)(Grant Nos.11925301+10 种基金12033006)supported by the NSFC(Grant Nos.11973002,and 12322303)supported by the NSFC(Grant No.12103041)supported by the NSFC(Grant Nos.11988101,and 11933004)supported by the NSFC(Grant No.U2031117)supported by the NSFC(Grant No.12033004)supported by the NSFC(Grant No.12273029)supported by the NSFC(Grant No.12221003)supported by the NSFC(Grant No.11933008)supported by the NSFC(Grant No.12090044)supported by the NSFC(Grant Nos.12041301,and 12121003)。
文摘The near-Earth(within~100 pc)supernova explosions in the past several million years can cause the global deposition of radioactive elements(e.g.,60Fe)on Earth.The remnants of such supernovae are too old to be easily identified.It is therefore of great interest to search for million-year-old near-Earth neutron stars or black holes,the products of supernovae.However,neutron stars and black holes are challenging to find even in our Solar neighbourhood if they are not radio pulsars or X-ray/γ-ray emitters.Here we report the discovery of one of the nearest(127.7±0.3 pc)neutron star candidates in a detached single-lined spectroscopic binary LAMOST J235456.73+335625.9(hereafter J2354).Utilizing the time-resolved ground-based spectroscopy and space photometry,we find that J2354 hosts an unseen compact object with M_(inv)being 1.4-1.6 M_(⊙).The follow-up Swift ultraviolet(UV)and X-ray observations suggest that the UV and X-ray emission is produced by the visible star rather than the compact object.Hence,J2354 probably harbours a neutron star rather than a hot ultramassive white dwarf.Two-hour exceptionally sensitive radio follow-up observations with Five-hundred-meter Aperture Spherical radio Telescope fail to reveal any pulsating radio signals at the 6σflux upper limit of 12.5μJy.Therefore,the neutron star candidate in J2354 can only be revealed via our time-resolved observations.Interestingly,the distance between J2354 and our Earth can be as close as~50 pc around 2.5 million years(Myrs)ago,as revealed by the Gaia kinematics.Our discovery demonstrates a promising way to unveil the hidden near-Earth neutron stars in binaries by exploring the optical time domain,thereby facilitating understanding of the metal-enrichment history in our Solar neighbourhood.
基金support of the National Natural Science Foundation of China (NSFC, Grant No.50776096).
文摘An experimental apparatus has been built to measure the flammability limits of combustible gases based on Chinesenational standard GB/T 12474-90. The flammability limits of four binary mixtures of R161/R134a,R152a/R134a, R161/N2 and R152a/N2 were measured with this apparatus at atmospheric pressure and ambienttemperature. The fuel inertization points (FIP) of these mixtures can be found from the envelopes. Comparisonswere made with the literature data; good agreement for most measurements was obtained. R134a was found tohave a better dilution effect than nitrogen in reducing the flammability of hydrofluorocarbons.
文摘Heat transfer coefficients in nucleate boiling on a smooth flat surface were measured for pure fluids of R-134a, propane, isobutane and their binary mixtures at different pressure from 0.1 to 0.6 MPa. Series of experiments with different heat flux and mixture concentrations were carried out. The influences of pressure and heat flux on the heat transfer coefficient for different pure fluids were studied. Isobutane and propane were used to make up binary mixtures. Compared to the pure components, binary mixtures show lower heat transfer coefficients. This reduction was more pronounced as the heat flux increasing. Several heat transfer correlations are obtained for different pure refrigerants and their binary mixtures.
文摘We demonstrate a facile and effective approach to significantly improve the photoluminescence of bulk MoS2 via laser thinning followed by gold particle decoration. Upon laser thinning of exfoliated bulk MoSz photoluminescence emerges from the laser-thinned region. After further treatment with an AuCl3 solution, gold particles self-assemble on the laser-thinned region and thick edges, further increasing the fluorescence of bulk MoS2 28 times and the Raman response 3 times. Such fluorescence enhancement can be attributed to both surface plasmon resonance and p-type doping induced by gold particles. The combination of laser thinning and AuCl3 treatment enables the functionalization of bulk MoS2 for optoelectronic applications. It can also provide a viable strategy for mask-free and area-selective p-type doping on single MoS2 flakes.
基金supported by the National Scientific and Technological Major Project(2017ZX10202203-003)the National Natural Science Foundation of China(81788101,31420103910,and 81630042)+1 种基金the 111 Project(B12001)the National Science Foundation of China for Fostering Talents in Basic Research(J1310027).
文摘HBV infection initiates hepatitis B and promotes liver cirrhosis and hepatocellular carcinoma.IFN-α is commonly used in hepatitis B therapy,but how it inhibits HBV is not fully understood.We screened 285 human interferon-stimulated genes(ISGs)for anti-HBV activity using a cell-based assay,which revealed several anti-HBV ISGs.Among these ISGs,SAMD4A was the strongest suppressor of HBV replication.We found the binding site of SAMD4A in HBV RNA,which was a previously unidentified Smaug recognition region(SRE)sequence conserved in HBV variants.SAMD4A binds to the SRE site in viral RNA to trigger its degradation.The SAM domain in SAMD4A is critical for RNA binding and the C-terminal domain of SAMD4A is required for SAMD4A anti-HBV function.Human SAMD4B is a homolog of human SAMD4A but is not an ISG,and the murine genome encodes SAMD4.All these SAMD4 proteins suppressed HBV replication when overexpressed in vitro and in vivo.We also showed that knocking out the Samd4 gene in hepatocytes led to a higher level of HBV replication in mice and AAV-delivered SAMD4A expression reduced the virus titer in HBVproducing transgenic mice.In addition,a database analysis revealed a negative correlation between the levels of SAMD4A/B and HBV in patients.Our data suggest that SAMD4A is an important anti-HBV ISG for use in IFN therapy of hepatitis B and that the levels of SAMD4A/B expression are related to HBV sensitivity in humans.
基金This work was supported by grants from the Chinese Ministry of Science and Technology National Major Scientific Research Program(2015CB943200)the Key Project Grant from the National Natural Science Foundation of China(31330027)+1 种基金the National Basic Research Program of China(2015CB553800)the Tsinghua Science Foundation(20111080963).
文摘The role of the p38 signaling pathway in the innate and adaptive immune responses has been well documented,especially in inflammatory cytokine production by dendritic cells(DCs).However,whether the p38 signaling pathway affects the important antigen(Ag)presentation function of DCs remains largely unknown.In this study,we reported that the deletion of p38αresulted in an impaired cross-presentation ability of CD8^(+) conventional DCs(cDCs)and a reduction in the direct presentation ability of CD8−cDCs ex vivo.Further study revealed that p38αhad a crucial role in Ag processing by CD8^(+) cDCs but did not affect the Ag uptake or co-stimulation of T cells.Moreover,p38αdeficiency led to reduced cross-priming of T cells in vivo.The production of the IL-12p40 and IL-12p70 cytokines by p38α-deficient cDCs was also significantly reduced.Our study identified a new role for p38αin modulating the important antigen cross-presentation function of DCs.
基金supported by the National Natural Science Foundation of China(31922034,82088102,91854208,92057204,31730058,82072777)Science and Technology Program of Fujian Provincial Health Commission(2021ZD02006)+3 种基金Xiamen Science and Technology Major Project(3502Z2020YJ05)Xiamen Municipal Bureau of Science and Technology(3502Z20209005)Fundamental Research Funds for the Central Universities(20720200014,20720200069,20720190084)Program of Introducing Talents of Discipline to Universities(BP2018017)。
文摘Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),is characterized by a strong production of inflammatory cytokines such as TNF and IL-6,which underlie the severity of the disease.However,the molecular mechanisms responsible for such a strong immune response remains unclear.Here,utilizing targeted tandem mass spectrometry to analyze serum metabolome and lipidome in COVID-19 patients at different temporal stages,we identified that 611 metabolites(of 1,039)were significantly altered in COVID-19 patients.Among them,two metabolites,agmatine and putrescine,were prominently elevated in the serum of patients;and 2-quinolinecarboxylate was changed in a biphasic manner,elevated during early COVID-19 infection but levelled off.When tested in mouse embryonic fibroblasts(MEFs)and macrophages,these 3 metabolites were found to activate the NF-κB pathway that plays a pivotal role in governing cytokine production.Importantly,these metabolites were each able to cause strong increase of TNF and IL-6 levels when administered to wildtype mice,but not in the mice lacking NF-κB.Intriguingly,these metabolites have little effects on the activation of interferon regulatory factors(IRFs)for the production of type I interferons(IFNs)for antiviral defenses.These data suggest that circulating metabolites resulting from COVID-19 infection may act as effectors to elicit the peculiar systemic inflammatory responses,exhibiting severely strong proinflammatory cytokine production with limited induction of the interferons.Our study may provide a rationale for development of drugs to alleviate inflammation in COVID-19 patients.
基金the National Natural Science Foundation of China (51376188)the National Basic Research Program of China (2011CB710701)
文摘Accurate modeling of the solubility behavior of CO_2 in the aqueous alkanolamine solutions is important to design and optimization of equipment and process. In this work, the thermodynamics of CO_2 in aqueous solution of N-methyldiethanolamine(MDEA) and piperazine(PZ) is studied by the electrolyte non-random two liquids(NRTL) model. The chemical equilibrium constants are calculated from the free Gibbs energy of formation, and the Henry's constants of CO_2 in MDEA and PZ are regressed to revise the value in the pure water. New experimental data from literatures are added to the regression process. Therefore, this model should provide a comprehensive thermodynamic representation for the quaternary system with broader ranges and more accurate predictions than previous work. Model results are compared to the experimental vapor-liquid equilibrium(VLE), speciation and heat of absorption data, which show that the model can predict the experimental data with reasonable accuracy.