The germination process of seeds is influenced by the interplay between two opposing factors,pectin methylesterase(PME)and pectin methylesterase inhibitor(PMEI),which collectively regulate patterns of pectin methylest...The germination process of seeds is influenced by the interplay between two opposing factors,pectin methylesterase(PME)and pectin methylesterase inhibitor(PMEI),which collectively regulate patterns of pectin methylesterification.Despite the recognized importance of pectin methylesterification in seed germination,the specific mechanisms that govern this process remain unclear.In this study,we demonstrated that the overexpression of GhPMEI53is associated with a decrease in PME activity and an increase in pectin methylesterification.This leads to seed cell wall softening,which positively regulates cotton seed germination.AtPMEI19,the homologue in Arabidopsis thaliana,plays a similar role in seed germination to GhPMEI53,indicating a conserved function and mechanism of PMEI in seed germination regulation.Further studies revealed that GhPMEI53 and AtPMEI19 directly contribute to promoting radicle protrusion and seed germination by inducing cell wall softening and reducing mechanical strength.Additionally,the pathways of abscicic acid(ABA)and gibberellin(GA)in the transgenic materials showed significant changes,suggesting that GhPMEI53/AtPMEI19-mediated pectin methylesterification serves as a regulatory signal for the related phytohormones involved in seed germination.In summary,GhPMEI53 and its homologs alter the mechanical properties of cell walls,which influence the mechanical resistance of the endosperm or testa.Moreover,they impact cellular phytohormone pathways(e.g.,ABA and GA)to regulate seed germination.These findings enhance our understanding of pectin methylesterification in cellular morphological dynamics and signaling transduction,and contribute to a more comprehensive understanding of the PME/PMEI gene superfamily in plants.展开更多
Previous theoretical studies have found that the concentration variations within a certain range have a prominent effect on inter-mineral equilibrium isotope fractionation(10^3 lna).Based on the density functional the...Previous theoretical studies have found that the concentration variations within a certain range have a prominent effect on inter-mineral equilibrium isotope fractionation(10^3 lna).Based on the density functional theory,we investigated how the average Ca–O bond length and the reduced partition function ratios(10^3 lnb)and103lna of 44 Ca/40 Ca in forsterite(Fo)are affected by its Ca concentration.Our results show that Ca–O bond length in forsterite ranges from 2.327 to 2.267 A with the Ca/(Ca+Mg)varying between a narrow range limited by an upper limit of 1/8 and a lower limit of 1/64.However,outside this narrow range,i.e.,Ca/(Ca+Mg)is lower than1/64 or higher than 1/8,Ca–O bond length becomes insensitive to Ca concentration and maintains to be a constant.Because the 10^3 lnb is negatively correlated with Ca–O bond length,the 10^3lnb significantly increases with decreasing Ca/(Ca+Mg)when 1/64<Ca/(Ca+Mg)<2/16.As a consequence,the 10^3lna between forsterite and other minerals also strongly depend on the Ca content in forsterite.Combining previous studies with our results,the heavier Ca isotopes enrichment sequence in minerals is:forsterite[orthopyroxene[clinopyroxene[calcite & diopside[dolomite[aragonite.Olivineand pyroxenes are enriched in heavier Ca isotope compared to carbonates.The 10^3lna between forsterite with a Ca/(Ca+Mg)of 1/64 and clinopyroxene(Ca/Mg=1/1,i.e.,diopside)is up to^0.64%at 1200 K.The large 103lnaFodiopsiderelative to the current analytical precision for Ca isotope measurements suggests that the dependence of10^3 lnaFo-diopsideon temperature can be used as a thermometer,similar to the one based on the 103lna of 44 Ca/40 Ca between orthopyroxene and diopside.These two Ca isotope thermometers both have a precision approximate to that of elemental thermometers and provide independent constraints on temperature.展开更多
Increasing reducing sugars(xylose and glucose) yield for bioethanol from corn stover depends strongly on optimization of pretreatment conditions. The optimum reaction conditions of two-stage liquid hot water(LHW) pret...Increasing reducing sugars(xylose and glucose) yield for bioethanol from corn stover depends strongly on optimization of pretreatment conditions. The optimum reaction conditions of two-stage liquid hot water(LHW) pretreatment based on total sugars yield were investigated. Under optimal conditions, the recovery of glucose of corn stover after two-stage LHW pretreatment and 72 h enzymatic digestion, reached 89.55%. In addition, acetic acid-rich spent liquor pretreatment and one-stage LHW pretreatment have been carried out to make comparisons with two-stage LHW treatment. Glucose yield 89.55% is superior to the recovery 83.38% using acetic acidrich spent liquor pretreatment or 80.58% using one-stage LHW pretreatment. The production of total sugars was increased by 7.8% when compared with one-stage pretreatment. Moreover, the structural features of the treated corn stover solid residues were also investigated by XRD and SEM technology in order to clarify the effects of the reaction on corn stover. The results indicated that the two-stage LHW pretreatment was an effective pretreatment method of corn stover to get most massive resource utilization, and it could be successfully applied to corn stover.展开更多
Seeds of soybeans and mung beans were soaked into five different concentrations (0, 0.05, 0.10, 0.20, 0.30 mg/L) of natural brassinolide ( NBR ) solution. According to the results, natural brassinolide treatment c...Seeds of soybeans and mung beans were soaked into five different concentrations (0, 0.05, 0.10, 0.20, 0.30 mg/L) of natural brassinolide ( NBR ) solution. According to the results, natural brassinolide treatment could improve seed germination rate and hypocotyl-radicle ratio of soybeans and mung beans and promote the growth of sprouts. To be specific, seed germination rate of soybeans reached the highest in 0.05 mg/L natural brassinolide treatment, which was im- proved by 25.0 percentage points compared with the control group, and the sprout length was improved by 4.33 em; 0.30 mg/L natural brassinolide exhibited the most significant promotion effect on seed germination and sprout growth of mung beans, seed germination rate was improved by 18.3 percentage points and sprout length was improved by 7.29 cm; hypocotyl-radiele ratio of soybean and mung bean sprouts reached the highest (2.96, 1.43 ) in 0.05 mg/L natural brassinolide treatment.展开更多
Adsorption equilibrium is of great importance for the preparative supercritical fluid chromatography(pre-SFC) in defining supercritical adsorption behavior and the industrial amplification.This paper presents adsorpti...Adsorption equilibrium is of great importance for the preparative supercritical fluid chromatography(pre-SFC) in defining supercritical adsorption behavior and the industrial amplification.This paper presents adsorption isotherms of Z-ligustilide from supercritical carbon dioxide(SC-CO_2) on C18-bonded silica.Adsorption behavior was studied at 305.15 K,313.15 K and 323.15 K with SC-CO_2 density varying from 0.687 g·cm^(-3) to0.863 g·cm^(-3) with the elution by characteristic points(ECP) method.The adsorption amount of Z-ligustilide from SC-CO_2 on C18-bonded silica decreased with the increasing density of the mobile phase as well as the increasing temperature.Adsorption equilibrium data were fitted by Langmuir and Freundlich isotherm models,and the Langmuir isotherm model performed better for describing the whole adsorption process on the column.The monolayer saturation adsorption capacity of Z-ligustilide is in the range of 3.0 × 10^(-4) mg·cm^(-3) to5.5 × 10^(-4) mg·cm^(-3) with an average value of 4.0 × 10^(-4) mg·cm^(-3).展开更多
The development of a process that could recover biofuel from industrial cellulose waste can not only reduce the negative environmental impacts by using fossil fuels, but also bring a green idea for the waste’s dispos...The development of a process that could recover biofuel from industrial cellulose waste can not only reduce the negative environmental impacts by using fossil fuels, but also bring a green idea for the waste’s disposing. In this study, hydrothermal pretreatment was optimized for cassava anaerobic residue, a cellulosic waste from cassava ethanol industry, to co-utilize xylose and glucose for producing bioethanol. The effect of the main pretreatment conditions, namely, temperature, solid content and time, was explored for the highest recovery of xylose in prehydrolysate and glucose in enzymatic hydrolysate. The single factor experiment results showed that the conditions for maximum xylose recovery in prehydrolysate and glucose recovery in enzymatic hydrolysate were 60℃, 75 min, 10% solids and 160℃, 75 min, 10% solids, respectively. Whereafter, response surface methodology(RSM) was applied to further optimize the pretreatment conditions for the maximum theoretical ethanol production through utilizing both xylose and glucose. A treatment at 163℃, for 59 min and with 9.5%solids was found optimal, with the highest ethanol production of 20.2 mg·g^-1 raw material. Furthermore, in order to assess the impacts of the pretreatment on cassava anaerobic residue, the changes in crystallinity and morphology for untreated and pretreated solids were investigated.展开更多
BACKGROUND: Drug-associated conditioned stimuli are a key factor to induce morphine relapse. To date, limited evidence is available regarding the impact of drug history on propensity or vulnerability to relapse after...BACKGROUND: Drug-associated conditioned stimuli are a key factor to induce morphine relapse. To date, limited evidence is available regarding the impact of drug history on propensity or vulnerability to relapse after long-term abstinence. OBJECTIVE: To determine the effect of morphine pre-exposure on acquisition, maintenance and reinstatement of morphine-induced conditioned place preference (CPP) in rats. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Laboratory of Behavior Pharmacology, Institute of Psychology, the Chinese Academy of Sciences, from March to September, 2006. MATERIALS: Morphine hydrochloride was purchased from Qinghai Pharmaceutical, China; CPP software was designed and developed by Taiji Software Company, Beijing, China. METHODS: A total of 64 Sprague Dawley rats were randomly assigned to eight groups (n = 8). Four morphine pretreatment regimens were used (subcutaneous injections, twice daily for 5 consecutive days and a total of 10 times): (1) "intensive" (morphine injections with doses escalating from 10 to 60 mg/kg; (2) "moderate" (one morphine injection at 5 mg/kg dose and one saline injection at 1 mL/kg daily for 5 days); and (3) "single" (nine saline injections at 1 mL/kg followed by one morphine injection at 5 mg/kg; (4) control (ten saline injections at 1 mL/kg). At 5 days after morphine pretreatment, animals were divided into two subgroups that underwent morphine conditioned or saline conditioned training. The test for acquisition of CPP was performed 24 hours after CPP training. The retention of morphine CPP was measured by repeated tests performed weekly for 1 month after the initial test of place preference. After extinction by pairing each chamber with saline, the reinstatement of place preference by low doses of morphine (0.05, 0.15, 0.45 mg/kg) was tested. MAIN OUTCOME MEASURES: Acquisition, maintenance, and recovery response of CPP behavior. RESULTS: The acquisition magnitude of morphine-induced CPP was not affected by prior morphine exposure (F3, 56=0.17, P 〉 0.05). However, rats treated with moderate or intensive morphine pretreatment showed a less persistent CPP (t = -1.36, P 〉 0.05; t = -1.18, P 〉 0.05), but their place preference was reinstated by a low dose of morphine priming (t = -2.55, P 〈 0.05; t = -2.54, P 〈 0.05). The retention and reinstatement of morphine-induced CPP did not differ between rats with single morphine pre-exposure and control rats. CONCLUSION: Morphine pretreatment enhanced reinstatement of morphine-induced CPP but with less persistence. Individuals with heavy drug exposure are more susceptible to drug relapse when re-exposed to addictive drugs.展开更多
Adsorption equilibria of paeoniflorin and albiflorin on a cyano-silica column(CN column) from the solution of supercritical carbon dioxide(scCO2) modified with ethanol were studied. The adsorption capacity at 308.15 K...Adsorption equilibria of paeoniflorin and albiflorin on a cyano-silica column(CN column) from the solution of supercritical carbon dioxide(scCO2) modified with ethanol were studied. The adsorption capacity at 308.15 K,313.15 K, 318.15 K and 323.15 K under pressures corresponding to carbon dioxide/ethanol densities from0.347 g·cm^-3 to 0.662 g·cm^-3 were determined using the elution by characteristic point method(ECP). The effects of temperature and pressure on the solute loading were investigated. The results showed that the lower the temperature, the higher the adsorption capacity. With the decrease of density of scCO2, the adsorption capacity strengthens. The maximum adsorption capacity of paeoniflorin(albiflorin) on the CN column was15.24 mg·ml^-1(31.14 mg·ml^-1) in the range of 0–1.84 mg·ml^-1(0–1.67 mg·ml^-1) of paeoniflorin(albiflorin)standard solution. The adsorption capacity of albiflorin was twice as much as that of paeoniflorin under the same conditions. Adsorption data of paeoniflorin and albiflorin could be well described by the Langmuir model and Freundlich model. Compared with the two model fitting results, the adsorption of paeoniflorin and albiflorin belonged to the monolayer adsorption under conditions of 308.15–323.15 K and 10–17 MPa.展开更多
In centralized cellular network architecture,the concept of virtualized Base Station(VBS) becomes attracting since it enables all base stations(BSs) to share computing resources in a dynamic manner. This can significa...In centralized cellular network architecture,the concept of virtualized Base Station(VBS) becomes attracting since it enables all base stations(BSs) to share computing resources in a dynamic manner. This can significantly improve the utilization efficiency of computing resources. In this paper,we study the computing resource allocation strategy for one VBS by considering the non-negligible effect of delay introduced by switches. Specifically,we formulate the VBS's sum computing rate maximization as a set optimization problem. To address this problem,we firstly propose a computing resource schedule algorithm,namely,weight before one-step-greedy(WBOSG),which has linear computation complexity and considerable performance. Then,OSG retreat(OSG-R) algorithm is developed to further improve the system performance at the expense of computational complexity. Simulation results under practical setting are provided to validate the proposed two algorithms.展开更多
Spectral computed tomography(CT)based on photon counting detectors can resolve the energy of every single photon interacting with the sensor layer and be used to analyze material attenuation information under differen...Spectral computed tomography(CT)based on photon counting detectors can resolve the energy of every single photon interacting with the sensor layer and be used to analyze material attenuation information under different energy ranges,which can be helpful for material decomposition studies.However,there is a considerable amount of inherent quantum noise in narrow energy bins,resulting in a low signal-to-noise ratio,which can consequently affect the material decomposition performance in the image domain.Deep learning technology is currently widely used in medical image segmentation,denoising,and recognition.In order to improve the results of material decomposition,we propose an attention-based global convolutional generative adversarial network(AGC-GAN)to decompose different materials for spectral CT.Specifically,our network is a global convolutional neural network based on an attention mechanism that is combined with a generative adversarial network.The global convolutional network based on the attention mechanism is used as the generator,and a patchGAN discriminant network is used as the discriminator.Meanwhile,a clinical spectral CT image dataset is used to verify the feasibility of our proposed approach.Extensive experimental results demonstrate that AGC-GAN achieves a better material decomposition performance than vanilla U-Net,fully convolutional network,and fully convolutional denseNet.Remarkably,the mean intersection over union,structural similarity,mean precision,PAcc,and mean F1-score of our method reach up to 87.31%,94.83%,93.22%,97.39%,and 93.05%,respectively.展开更多
Mobile Edge Computing(MEC)-based computation offloading is a promising application paradigm for serving large numbers of users with various delay and energy requirements.In this paper,we propose a flexible MECbased re...Mobile Edge Computing(MEC)-based computation offloading is a promising application paradigm for serving large numbers of users with various delay and energy requirements.In this paper,we propose a flexible MECbased requirement-adaptive partial offloading model to accommodate each user's specific preference regarding delay and energy consumption.To address the dimensional differences between time and energy,we introduce two normalized parameters and then derive the computational overhead of processing tasks.Different from existing works,this paper considers practical variations in the user request patterns,and exploits a flexible partial offloading mode to minimize computation overheads subject to tolerable delay,task workload and power constraints.Since the resulting problem is non-convex,we decouple it into two convex subproblems and present an iterative algorithm to obtain a feasible offloading solution.Numerical experiments show that our proposed scheme achieves a significant improvement in computation overheads compared with existing schemes.展开更多
INTRODUCTION Addiction is a major global risk factor for disability and premature death'and has become a public health and social problem worldwide.Despite substantial investments from governments and research ins...INTRODUCTION Addiction is a major global risk factor for disability and premature death'and has become a public health and social problem worldwide.Despite substantial investments from governments and research institutionsglobally,current addictionmedicine research remains centred in Western countries.However,theories,models and results from western-centric research may not be applicable to different cultures.Non-Western countries such as China and Iran,and Western countries are committed to establishing addiction prevention and treatment tailored to their unique histories and cultures.To foster a global addiction science,it is important to increase the diversity of evidence without preconceived biases.展开更多
After explorations in a diversity of single-atom nanozymes(SAzymes),developing dual-centered SAzymes becomes a promising approach for superior catalytic performance.But confusing mechanisms including atomic coordinati...After explorations in a diversity of single-atom nanozymes(SAzymes),developing dual-centered SAzymes becomes a promising approach for superior catalytic performance.But confusing mechanisms including atomic coordination,spatial configuration,and metal–metal atom interaction hinder the development and design of SAzymes.Herein,a dual-centered Fe-Cu-N_(x)SAzyme exhibits excellent peroxidase(POD)-and catalase(CAT)-like activities with d-band center(ε_(d))coordination of Fe and Cu in multiple reaction stages,which plays a critical role in the adsorption of H_(2)O_(2)molecule and H_(2)O and O_(2)release.Therefore,the dband center coordination,which can be represented byε_(d)(Fe)–ε_(d)(Cu)shifts,leads to the competition between one-side and bilateral adsorption,which determines the favorable reaction path with lower energy barriers.Based on experimental statistics,simulated formation energies,and reaction barriers,3 configurations,Fe-Cu-N6-I,Fe-Cu-N_(8)-II,and Fe-Cu-N_(8)-III,are modeled and validated.Impressively,configuration-dependent catalytic selectivity and the competition between one-side and bilateral adsorption can be unveiled by d-band center coordination paradigm analysis.Theoretical simulations suggest that the unsymmetrical charge distribution over the three Fe-Cu configurations could tune the adsorption strength compared with the counterparts FeN_(4)and CuN_(4).The present work provides a potential route for optimizing enzyme-like catalysis by designing the dual-or even triple-metal SAzymes,which demonstrates the large space to modulate the metal atomic configuration and interaction.展开更多
Whole wheat bread is widely available worldwide,but it is always associated with less desirable dough processibility,small loaf volume,firm and gritty texture,and other distinctive attributes compared to white bread.E...Whole wheat bread is widely available worldwide,but it is always associated with less desirable dough processibility,small loaf volume,firm and gritty texture,and other distinctive attributes compared to white bread.Emulsifiers are commonly used to improve dough handling and baking quality during bread production.In present study,five emulsifiers(diacetyl tartaric acid esters of mono-and diglycerides(DATEM),polysorbate 80,sodium stearoyl lactylate(SSL),soy lecithin,and sucrose esters)were added during dough preparation of the whole wheat flour at 0.2%,0.5%,and 1.0%(flour weight basis).Dough rheological behavior and bread quality attributes,such as specific loaf volume and hardness,were measured.The results showed that DATEM,sucrose esters,and SSL increased the resistance to extension of the dough,whereas soy lecithin and polysorbate 80 increased the extensibility.Soy lecithin and polysorbate 80 were the only emulsifiers that significantly increased loaf volume compared to the control.Adding higher levels(1.0%)of sucrose esters,polysorbate 80,and SSL increased the formation of amylose-lipid complex and mitigate the crumb staling during storage.The results suggested that the emulsifiers could be applied to contribute to optimum functional quality of whole wheat bread.展开更多
BACKGROUND: Studies have demonstrated that lead exposure can result in cognitive dysfunction and behavior disorders. However, lead exposure impairments vary under different experimental conditions. OBJECTIVE: To det...BACKGROUND: Studies have demonstrated that lead exposure can result in cognitive dysfunction and behavior disorders. However, lead exposure impairments vary under different experimental conditions. OBJECTIVE: To detect changes in spatial learning and memory following low-level lead exposure in rats, in Morris water maze test under the same experimental condition used to analyze lead exposure effects on various memory types and learning processes. DESIGN AND SETTING: The experiment was conducted at the Animal Laboratory, Institute of Psychology, Chinese Academy of Science between February 2005 and March 2006. One-way analysis of variance (ANOVA) and behavioral observations were performed. MATERIALS: Sixteen male, healthy, adult, Sprague Dawley rats were randomized into normal con-trol and lead exposure groups (n = 8). METHODS: Rats in the normal control group were fed distilled water, and those in the lead exposure group were fed 250 mL of 0.05% lead acetate once per day. At day 28, all rats performed the Morris water maze test, consisting of four phases: space navigation, probe test, working memory test, and visual cue test. MAIN OUTCOME MEASURES: Place navigation in the Morris water maze was used to evaluate spatial learning and memory, probe trials for spatial reference memory, working memory test for spatial working memory, and visual cue test for non-spatial cognitive function. Perkin-Elmer Model 300 Atomic Absorption Spectrometer was utilized to determine blood lead levels in rats. RESULTS: (1) In the working memory test, the time to reach the platform remained unchanged between the control and lead exposure groups (F(1,1) = 0.007, P = 0.935). A visible decrease in escape latencies was observed in each group (P = 0.028). However, there was no significant difference between the two groups (F(1,1) = 1.869, P = 0.193). The working memory probe test demonstrated no change between the two groups in the time spent in the target quadrant during the working memory probe test (F(1,1) = 1.869, P = 0.193). However, by day 4, differences were observed in the working memory test (P 〈 0.01). (2) Multivariate repetitive measure and ANOVA in place navigation presented no significant difference between the two groups (F(1,1) = 0.579, P = 0.459). (3) Spatial probe test demonstrated that the time to reach the platform was significantly different between the two groups (F(1,1) = 4.587, P = 0.048), and one-way ANOVA showed no significant difference in swimming speed between the two groups (F(1,1) = 1.528, P = 0.237). (4) In the visual cue test, all rats reached the platform within 15 seconds, with no significant difference (F(1,1) = 0.579, P = 0.459). (5) During experimentation, all rats increased in body mass, but there was no difference between the two groups (F(1,1) = 0.05, P = 0.943). At day 28 of 0.05% lead exposure, the blood lead level was 29.72 μg/L in the lead exposure group and 5.86 μg/L in the control group (P 〈 0.01). CONCLUSION: The present results revealed low-level lead exposure significantly impaired spatial reference memory and spatial working memory, but had no effect on spatial learning.展开更多
Ethylene is one of the most important basic chemicals in the modern chemical industry.Thermal or catalytic cracking of hydrocarbons is the main industrial technologies nowadays,which suffer from equilibriumlimitation ...Ethylene is one of the most important basic chemicals in the modern chemical industry.Thermal or catalytic cracking of hydrocarbons is the main industrial technologies nowadays,which suffer from equilibriumlimitation and rapid coke formation.The oxidative dehydrogenation of ethane(ODHE)is considered to be a promising alternative process since it overcomes equilibrium-limitations,avoids catalyst deactivation by coke formation,and decreases the number of side reactions.In this study,particle-resolved 2 D CFD simulations of fixed-beds filled with eggshell catalysts coupled with micro-kinetics of Pt-catalyzed ODHE were performed to understand the effect of operation conditions and catalyst properties on ethylene selectivity.The catalyst bed was created by discrete element method(DEM)and the central longitudinal section of the reactor tube was defined as the 2 D simulation region.Both of the homogeneous and catalytic heterogeneous chemical reactions were described by detailed micro-kinetics within the particle-resolved CFD simulation.At first,the established model of monolith reactors was verified by comparing the simulated results with experimental results reported in literature.Then,the effects of operation conditions and catalyst concentration on the ethylene selectivity in randomly packed beds were explored.The specific variation of certain operation conditions including inlet flow rate,inlet temperature,pressure,inlet C2 H6/O2 ratio and N2 dilution ratio can effectively increase ethylene selectivity.And the reduction of ratio of catalytic active area to geometric area Fcat/georepresenting catalyst properties from 140 to 30 increases the selectivity from 42.2%to 59.3%.This research can provide reference for the industrialization of ODHE process in the future.展开更多
[Objectives] This study was conducted to determine in-vitro antibacterial effect of 58 Chinese herbs on Staphylococcus aureus,and screen single Chinese herbs with better in-vitro antibacterial effect for formulation o...[Objectives] This study was conducted to determine in-vitro antibacterial effect of 58 Chinese herbs on Staphylococcus aureus,and screen single Chinese herbs with better in-vitro antibacterial effect for formulation of prescription. [Methods]Effective components in Chinese herbs were extracted with water,and inhibition zone diameters and minimal inhibitory concentrations of the 58 Chinese herbs against S. aureus were determined by agar plate punching method and micro two-fold method,respectively. [Results] Twenty two kinds of Chinese herbs including Terminalia chebula Retz.,Anemarrhena asphodeloides Bunge.,Prunella vulgaris L,Rheum palmatum L. and Mosla chinensis Maxim. had better antibacterial effect,among which T. chebula Retz.,A. asphodeloides Bunge.,P. vulgaris L,R. palmatum L. and C. sappan Linn showed the best antibacterial effect,with average inhibition zone over 20 mm and MIC lower than 15. 6 mg/ml.[Conclusions]Traditional Chinese herbs have certain antibacterial effect,and this study will provide important theoretical reference for clinical medication and development of prescription.展开更多
Dear Editor,Short-range wireless communications have been widely used in our daily life,but the pursuit of a better communication experience never stops,leading to the more stringent requirements of emerging applicati...Dear Editor,Short-range wireless communications have been widely used in our daily life,but the pursuit of a better communication experience never stops,leading to the more stringent requirements of emerging applications.^(1)For example,remote control applications such as telesurgery require a delay of less than 1 ms.^(2)Indus-trial closed-loop control applications such as automatic assembly lines have a reliability requirement of at least 99.999%.展开更多
基金funded by the National Natural Science Foundation of China(32072022)the Nanfan Special Project,CAAS(YBXM07)the Hainan Yazhou Bay Seed Laboratory,China(B23CJ0208)。
文摘The germination process of seeds is influenced by the interplay between two opposing factors,pectin methylesterase(PME)and pectin methylesterase inhibitor(PMEI),which collectively regulate patterns of pectin methylesterification.Despite the recognized importance of pectin methylesterification in seed germination,the specific mechanisms that govern this process remain unclear.In this study,we demonstrated that the overexpression of GhPMEI53is associated with a decrease in PME activity and an increase in pectin methylesterification.This leads to seed cell wall softening,which positively regulates cotton seed germination.AtPMEI19,the homologue in Arabidopsis thaliana,plays a similar role in seed germination to GhPMEI53,indicating a conserved function and mechanism of PMEI in seed germination regulation.Further studies revealed that GhPMEI53 and AtPMEI19 directly contribute to promoting radicle protrusion and seed germination by inducing cell wall softening and reducing mechanical strength.Additionally,the pathways of abscicic acid(ABA)and gibberellin(GA)in the transgenic materials showed significant changes,suggesting that GhPMEI53/AtPMEI19-mediated pectin methylesterification serves as a regulatory signal for the related phytohormones involved in seed germination.In summary,GhPMEI53 and its homologs alter the mechanical properties of cell walls,which influence the mechanical resistance of the endosperm or testa.Moreover,they impact cellular phytohormone pathways(e.g.,ABA and GA)to regulate seed germination.These findings enhance our understanding of pectin methylesterification in cellular morphological dynamics and signaling transduction,and contribute to a more comprehensive understanding of the PME/PMEI gene superfamily in plants.
基金financially supported by the Natural Science Foundation of China (Nos. 41721002, 41473011)Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund
文摘Previous theoretical studies have found that the concentration variations within a certain range have a prominent effect on inter-mineral equilibrium isotope fractionation(10^3 lna).Based on the density functional theory,we investigated how the average Ca–O bond length and the reduced partition function ratios(10^3 lnb)and103lna of 44 Ca/40 Ca in forsterite(Fo)are affected by its Ca concentration.Our results show that Ca–O bond length in forsterite ranges from 2.327 to 2.267 A with the Ca/(Ca+Mg)varying between a narrow range limited by an upper limit of 1/8 and a lower limit of 1/64.However,outside this narrow range,i.e.,Ca/(Ca+Mg)is lower than1/64 or higher than 1/8,Ca–O bond length becomes insensitive to Ca concentration and maintains to be a constant.Because the 10^3 lnb is negatively correlated with Ca–O bond length,the 10^3lnb significantly increases with decreasing Ca/(Ca+Mg)when 1/64<Ca/(Ca+Mg)<2/16.As a consequence,the 10^3lna between forsterite and other minerals also strongly depend on the Ca content in forsterite.Combining previous studies with our results,the heavier Ca isotopes enrichment sequence in minerals is:forsterite[orthopyroxene[clinopyroxene[calcite & diopside[dolomite[aragonite.Olivineand pyroxenes are enriched in heavier Ca isotope compared to carbonates.The 10^3lna between forsterite with a Ca/(Ca+Mg)of 1/64 and clinopyroxene(Ca/Mg=1/1,i.e.,diopside)is up to^0.64%at 1200 K.The large 103lnaFodiopsiderelative to the current analytical precision for Ca isotope measurements suggests that the dependence of10^3 lnaFo-diopsideon temperature can be used as a thermometer,similar to the one based on the 103lna of 44 Ca/40 Ca between orthopyroxene and diopside.These two Ca isotope thermometers both have a precision approximate to that of elemental thermometers and provide independent constraints on temperature.
文摘Increasing reducing sugars(xylose and glucose) yield for bioethanol from corn stover depends strongly on optimization of pretreatment conditions. The optimum reaction conditions of two-stage liquid hot water(LHW) pretreatment based on total sugars yield were investigated. Under optimal conditions, the recovery of glucose of corn stover after two-stage LHW pretreatment and 72 h enzymatic digestion, reached 89.55%. In addition, acetic acid-rich spent liquor pretreatment and one-stage LHW pretreatment have been carried out to make comparisons with two-stage LHW treatment. Glucose yield 89.55% is superior to the recovery 83.38% using acetic acidrich spent liquor pretreatment or 80.58% using one-stage LHW pretreatment. The production of total sugars was increased by 7.8% when compared with one-stage pretreatment. Moreover, the structural features of the treated corn stover solid residues were also investigated by XRD and SEM technology in order to clarify the effects of the reaction on corn stover. The results indicated that the two-stage LHW pretreatment was an effective pretreatment method of corn stover to get most massive resource utilization, and it could be successfully applied to corn stover.
基金Supported by Key Joint Foundation for Fostering Talents of NSFC-Henan Province(U1204307)Key Project of Science and Technology of Henan Province(102102110155,142102110173,152102210334)Cultivation Fund of Luoyang Normal University(2013-PYJJ-001,10000993)
文摘Seeds of soybeans and mung beans were soaked into five different concentrations (0, 0.05, 0.10, 0.20, 0.30 mg/L) of natural brassinolide ( NBR ) solution. According to the results, natural brassinolide treatment could improve seed germination rate and hypocotyl-radicle ratio of soybeans and mung beans and promote the growth of sprouts. To be specific, seed germination rate of soybeans reached the highest in 0.05 mg/L natural brassinolide treatment, which was im- proved by 25.0 percentage points compared with the control group, and the sprout length was improved by 4.33 em; 0.30 mg/L natural brassinolide exhibited the most significant promotion effect on seed germination and sprout growth of mung beans, seed germination rate was improved by 18.3 percentage points and sprout length was improved by 7.29 cm; hypocotyl-radiele ratio of soybean and mung bean sprouts reached the highest (2.96, 1.43 ) in 0.05 mg/L natural brassinolide treatment.
文摘Adsorption equilibrium is of great importance for the preparative supercritical fluid chromatography(pre-SFC) in defining supercritical adsorption behavior and the industrial amplification.This paper presents adsorption isotherms of Z-ligustilide from supercritical carbon dioxide(SC-CO_2) on C18-bonded silica.Adsorption behavior was studied at 305.15 K,313.15 K and 323.15 K with SC-CO_2 density varying from 0.687 g·cm^(-3) to0.863 g·cm^(-3) with the elution by characteristic points(ECP) method.The adsorption amount of Z-ligustilide from SC-CO_2 on C18-bonded silica decreased with the increasing density of the mobile phase as well as the increasing temperature.Adsorption equilibrium data were fitted by Langmuir and Freundlich isotherm models,and the Langmuir isotherm model performed better for describing the whole adsorption process on the column.The monolayer saturation adsorption capacity of Z-ligustilide is in the range of 3.0 × 10^(-4) mg·cm^(-3) to5.5 × 10^(-4) mg·cm^(-3) with an average value of 4.0 × 10^(-4) mg·cm^(-3).
基金financial support from Key Laboratory for Green Chemical Technology of Ministry of Education, R&D Center for Petrochemical Technology, Tianjin University
文摘The development of a process that could recover biofuel from industrial cellulose waste can not only reduce the negative environmental impacts by using fossil fuels, but also bring a green idea for the waste’s disposing. In this study, hydrothermal pretreatment was optimized for cassava anaerobic residue, a cellulosic waste from cassava ethanol industry, to co-utilize xylose and glucose for producing bioethanol. The effect of the main pretreatment conditions, namely, temperature, solid content and time, was explored for the highest recovery of xylose in prehydrolysate and glucose in enzymatic hydrolysate. The single factor experiment results showed that the conditions for maximum xylose recovery in prehydrolysate and glucose recovery in enzymatic hydrolysate were 60℃, 75 min, 10% solids and 160℃, 75 min, 10% solids, respectively. Whereafter, response surface methodology(RSM) was applied to further optimize the pretreatment conditions for the maximum theoretical ethanol production through utilizing both xylose and glucose. A treatment at 163℃, for 59 min and with 9.5%solids was found optimal, with the highest ethanol production of 20.2 mg·g^-1 raw material. Furthermore, in order to assess the impacts of the pretreatment on cassava anaerobic residue, the changes in crystallinity and morphology for untreated and pretreated solids were investigated.
基金the National Key Basic Research Pro-gram of China, No. 2009CB522002the National Natural Science Foundation of China, No. 30770719Chinese Academy of Sciences Grants, No. KSCX1-YW-R-68
文摘BACKGROUND: Drug-associated conditioned stimuli are a key factor to induce morphine relapse. To date, limited evidence is available regarding the impact of drug history on propensity or vulnerability to relapse after long-term abstinence. OBJECTIVE: To determine the effect of morphine pre-exposure on acquisition, maintenance and reinstatement of morphine-induced conditioned place preference (CPP) in rats. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Laboratory of Behavior Pharmacology, Institute of Psychology, the Chinese Academy of Sciences, from March to September, 2006. MATERIALS: Morphine hydrochloride was purchased from Qinghai Pharmaceutical, China; CPP software was designed and developed by Taiji Software Company, Beijing, China. METHODS: A total of 64 Sprague Dawley rats were randomly assigned to eight groups (n = 8). Four morphine pretreatment regimens were used (subcutaneous injections, twice daily for 5 consecutive days and a total of 10 times): (1) "intensive" (morphine injections with doses escalating from 10 to 60 mg/kg; (2) "moderate" (one morphine injection at 5 mg/kg dose and one saline injection at 1 mL/kg daily for 5 days); and (3) "single" (nine saline injections at 1 mL/kg followed by one morphine injection at 5 mg/kg; (4) control (ten saline injections at 1 mL/kg). At 5 days after morphine pretreatment, animals were divided into two subgroups that underwent morphine conditioned or saline conditioned training. The test for acquisition of CPP was performed 24 hours after CPP training. The retention of morphine CPP was measured by repeated tests performed weekly for 1 month after the initial test of place preference. After extinction by pairing each chamber with saline, the reinstatement of place preference by low doses of morphine (0.05, 0.15, 0.45 mg/kg) was tested. MAIN OUTCOME MEASURES: Acquisition, maintenance, and recovery response of CPP behavior. RESULTS: The acquisition magnitude of morphine-induced CPP was not affected by prior morphine exposure (F3, 56=0.17, P 〉 0.05). However, rats treated with moderate or intensive morphine pretreatment showed a less persistent CPP (t = -1.36, P 〉 0.05; t = -1.18, P 〉 0.05), but their place preference was reinstated by a low dose of morphine priming (t = -2.55, P 〈 0.05; t = -2.54, P 〈 0.05). The retention and reinstatement of morphine-induced CPP did not differ between rats with single morphine pre-exposure and control rats. CONCLUSION: Morphine pretreatment enhanced reinstatement of morphine-induced CPP but with less persistence. Individuals with heavy drug exposure are more susceptible to drug relapse when re-exposed to addictive drugs.
文摘Adsorption equilibria of paeoniflorin and albiflorin on a cyano-silica column(CN column) from the solution of supercritical carbon dioxide(scCO2) modified with ethanol were studied. The adsorption capacity at 308.15 K,313.15 K, 318.15 K and 323.15 K under pressures corresponding to carbon dioxide/ethanol densities from0.347 g·cm^-3 to 0.662 g·cm^-3 were determined using the elution by characteristic point method(ECP). The effects of temperature and pressure on the solute loading were investigated. The results showed that the lower the temperature, the higher the adsorption capacity. With the decrease of density of scCO2, the adsorption capacity strengthens. The maximum adsorption capacity of paeoniflorin(albiflorin) on the CN column was15.24 mg·ml^-1(31.14 mg·ml^-1) in the range of 0–1.84 mg·ml^-1(0–1.67 mg·ml^-1) of paeoniflorin(albiflorin)standard solution. The adsorption capacity of albiflorin was twice as much as that of paeoniflorin under the same conditions. Adsorption data of paeoniflorin and albiflorin could be well described by the Langmuir model and Freundlich model. Compared with the two model fitting results, the adsorption of paeoniflorin and albiflorin belonged to the monolayer adsorption under conditions of 308.15–323.15 K and 10–17 MPa.
基金funded by the key project of the National Natural Science Foundation of China (No.61431001)the National High-Tech R&D Program (863 Program 2015AA01A705)New Technology Star Plan of Beijing (No.xx2013052)
文摘In centralized cellular network architecture,the concept of virtualized Base Station(VBS) becomes attracting since it enables all base stations(BSs) to share computing resources in a dynamic manner. This can significantly improve the utilization efficiency of computing resources. In this paper,we study the computing resource allocation strategy for one VBS by considering the non-negligible effect of delay introduced by switches. Specifically,we formulate the VBS's sum computing rate maximization as a set optimization problem. To address this problem,we firstly propose a computing resource schedule algorithm,namely,weight before one-step-greedy(WBOSG),which has linear computation complexity and considerable performance. Then,OSG retreat(OSG-R) algorithm is developed to further improve the system performance at the expense of computational complexity. Simulation results under practical setting are provided to validate the proposed two algorithms.
基金supported by National Natural Science Foundation of China (No.62101136)Shanghai Sailing Program (No.21YF1402800)+3 种基金Shanghai Municipal Science and Technology Major Project (No.2018SHZDZX01)ZJLab,Shanghai Municipal of Science and Technology Project (No.20JC1419500)Natural Science Foundation of Chongqing (No.CSTB2022NSCQ-MSX0360)Shanghai Center for Brain Science and Brain-inspired Technology.
文摘Spectral computed tomography(CT)based on photon counting detectors can resolve the energy of every single photon interacting with the sensor layer and be used to analyze material attenuation information under different energy ranges,which can be helpful for material decomposition studies.However,there is a considerable amount of inherent quantum noise in narrow energy bins,resulting in a low signal-to-noise ratio,which can consequently affect the material decomposition performance in the image domain.Deep learning technology is currently widely used in medical image segmentation,denoising,and recognition.In order to improve the results of material decomposition,we propose an attention-based global convolutional generative adversarial network(AGC-GAN)to decompose different materials for spectral CT.Specifically,our network is a global convolutional neural network based on an attention mechanism that is combined with a generative adversarial network.The global convolutional network based on the attention mechanism is used as the generator,and a patchGAN discriminant network is used as the discriminator.Meanwhile,a clinical spectral CT image dataset is used to verify the feasibility of our proposed approach.Extensive experimental results demonstrate that AGC-GAN achieves a better material decomposition performance than vanilla U-Net,fully convolutional network,and fully convolutional denseNet.Remarkably,the mean intersection over union,structural similarity,mean precision,PAcc,and mean F1-score of our method reach up to 87.31%,94.83%,93.22%,97.39%,and 93.05%,respectively.
基金This work was supported in part by the National Natural Science Foundation of China under Grant 62171113 and 61941113in part by the Fundamental Research Funds for the Central Universities under Grant N2116003 and N2116011.
文摘Mobile Edge Computing(MEC)-based computation offloading is a promising application paradigm for serving large numbers of users with various delay and energy requirements.In this paper,we propose a flexible MECbased requirement-adaptive partial offloading model to accommodate each user's specific preference regarding delay and energy consumption.To address the dimensional differences between time and energy,we introduce two normalized parameters and then derive the computational overhead of processing tasks.Different from existing works,this paper considers practical variations in the user request patterns,and exploits a flexible partial offloading mode to minimize computation overheads subject to tolerable delay,task workload and power constraints.Since the resulting problem is non-convex,we decouple it into two convex subproblems and present an iterative algorithm to obtain a feasible offloading solution.Numerical experiments show that our proposed scheme achieves a significant improvement in computation overheads compared with existing schemes.
文摘INTRODUCTION Addiction is a major global risk factor for disability and premature death'and has become a public health and social problem worldwide.Despite substantial investments from governments and research institutionsglobally,current addictionmedicine research remains centred in Western countries.However,theories,models and results from western-centric research may not be applicable to different cultures.Non-Western countries such as China and Iran,and Western countries are committed to establishing addiction prevention and treatment tailored to their unique histories and cultures.To foster a global addiction science,it is important to increase the diversity of evidence without preconceived biases.
基金supported by the National Key Research and Development Program of China(Nos.2021YFF1200700 and 2021YFF1200701)the National Natural Science Foundation of China(Nos.91859101,81971744,U1932107,82001952,11804248,82302361,and 82302381)+5 种基金Outstanding Youth Funds of Tianjin(No.2021FJ-0009)STI 2030-Major Projects(No.2022ZD0210200)National Natural Science Foundation of Tianjin(Nos.19JCZDJC34000,20JCYBJC00940,21JCYBJC00550,21JCZDJC00620,and 21JCYBJC00490)the Key Projects of Tianjin Natural Fund(No.21JCZDJC00490)the Innovation Foundation of Tianjin University,China Postdoctoral Science Foundation(No.2023M732601)CAS Interdisciplinary Innovation Team(No.JCTD-2020-08).
文摘After explorations in a diversity of single-atom nanozymes(SAzymes),developing dual-centered SAzymes becomes a promising approach for superior catalytic performance.But confusing mechanisms including atomic coordination,spatial configuration,and metal–metal atom interaction hinder the development and design of SAzymes.Herein,a dual-centered Fe-Cu-N_(x)SAzyme exhibits excellent peroxidase(POD)-and catalase(CAT)-like activities with d-band center(ε_(d))coordination of Fe and Cu in multiple reaction stages,which plays a critical role in the adsorption of H_(2)O_(2)molecule and H_(2)O and O_(2)release.Therefore,the dband center coordination,which can be represented byε_(d)(Fe)–ε_(d)(Cu)shifts,leads to the competition between one-side and bilateral adsorption,which determines the favorable reaction path with lower energy barriers.Based on experimental statistics,simulated formation energies,and reaction barriers,3 configurations,Fe-Cu-N6-I,Fe-Cu-N_(8)-II,and Fe-Cu-N_(8)-III,are modeled and validated.Impressively,configuration-dependent catalytic selectivity and the competition between one-side and bilateral adsorption can be unveiled by d-band center coordination paradigm analysis.Theoretical simulations suggest that the unsymmetrical charge distribution over the three Fe-Cu configurations could tune the adsorption strength compared with the counterparts FeN_(4)and CuN_(4).The present work provides a potential route for optimizing enzyme-like catalysis by designing the dual-or even triple-metal SAzymes,which demonstrates the large space to modulate the metal atomic configuration and interaction.
基金the USDA National Institute of Food and Agriculture Hatch project KS17HA1008USDA Agricultural Research Service Cooperative Agreement 58-3020-9-017.
文摘Whole wheat bread is widely available worldwide,but it is always associated with less desirable dough processibility,small loaf volume,firm and gritty texture,and other distinctive attributes compared to white bread.Emulsifiers are commonly used to improve dough handling and baking quality during bread production.In present study,five emulsifiers(diacetyl tartaric acid esters of mono-and diglycerides(DATEM),polysorbate 80,sodium stearoyl lactylate(SSL),soy lecithin,and sucrose esters)were added during dough preparation of the whole wheat flour at 0.2%,0.5%,and 1.0%(flour weight basis).Dough rheological behavior and bread quality attributes,such as specific loaf volume and hardness,were measured.The results showed that DATEM,sucrose esters,and SSL increased the resistance to extension of the dough,whereas soy lecithin and polysorbate 80 increased the extensibility.Soy lecithin and polysorbate 80 were the only emulsifiers that significantly increased loaf volume compared to the control.Adding higher levels(1.0%)of sucrose esters,polysorbate 80,and SSL increased the formation of amylose-lipid complex and mitigate the crumb staling during storage.The results suggested that the emulsifiers could be applied to contribute to optimum functional quality of whole wheat bread.
文摘BACKGROUND: Studies have demonstrated that lead exposure can result in cognitive dysfunction and behavior disorders. However, lead exposure impairments vary under different experimental conditions. OBJECTIVE: To detect changes in spatial learning and memory following low-level lead exposure in rats, in Morris water maze test under the same experimental condition used to analyze lead exposure effects on various memory types and learning processes. DESIGN AND SETTING: The experiment was conducted at the Animal Laboratory, Institute of Psychology, Chinese Academy of Science between February 2005 and March 2006. One-way analysis of variance (ANOVA) and behavioral observations were performed. MATERIALS: Sixteen male, healthy, adult, Sprague Dawley rats were randomized into normal con-trol and lead exposure groups (n = 8). METHODS: Rats in the normal control group were fed distilled water, and those in the lead exposure group were fed 250 mL of 0.05% lead acetate once per day. At day 28, all rats performed the Morris water maze test, consisting of four phases: space navigation, probe test, working memory test, and visual cue test. MAIN OUTCOME MEASURES: Place navigation in the Morris water maze was used to evaluate spatial learning and memory, probe trials for spatial reference memory, working memory test for spatial working memory, and visual cue test for non-spatial cognitive function. Perkin-Elmer Model 300 Atomic Absorption Spectrometer was utilized to determine blood lead levels in rats. RESULTS: (1) In the working memory test, the time to reach the platform remained unchanged between the control and lead exposure groups (F(1,1) = 0.007, P = 0.935). A visible decrease in escape latencies was observed in each group (P = 0.028). However, there was no significant difference between the two groups (F(1,1) = 1.869, P = 0.193). The working memory probe test demonstrated no change between the two groups in the time spent in the target quadrant during the working memory probe test (F(1,1) = 1.869, P = 0.193). However, by day 4, differences were observed in the working memory test (P 〈 0.01). (2) Multivariate repetitive measure and ANOVA in place navigation presented no significant difference between the two groups (F(1,1) = 0.579, P = 0.459). (3) Spatial probe test demonstrated that the time to reach the platform was significantly different between the two groups (F(1,1) = 4.587, P = 0.048), and one-way ANOVA showed no significant difference in swimming speed between the two groups (F(1,1) = 1.528, P = 0.237). (4) In the visual cue test, all rats reached the platform within 15 seconds, with no significant difference (F(1,1) = 0.579, P = 0.459). (5) During experimentation, all rats increased in body mass, but there was no difference between the two groups (F(1,1) = 0.05, P = 0.943). At day 28 of 0.05% lead exposure, the blood lead level was 29.72 μg/L in the lead exposure group and 5.86 μg/L in the control group (P 〈 0.01). CONCLUSION: The present results revealed low-level lead exposure significantly impaired spatial reference memory and spatial working memory, but had no effect on spatial learning.
文摘Ethylene is one of the most important basic chemicals in the modern chemical industry.Thermal or catalytic cracking of hydrocarbons is the main industrial technologies nowadays,which suffer from equilibriumlimitation and rapid coke formation.The oxidative dehydrogenation of ethane(ODHE)is considered to be a promising alternative process since it overcomes equilibrium-limitations,avoids catalyst deactivation by coke formation,and decreases the number of side reactions.In this study,particle-resolved 2 D CFD simulations of fixed-beds filled with eggshell catalysts coupled with micro-kinetics of Pt-catalyzed ODHE were performed to understand the effect of operation conditions and catalyst properties on ethylene selectivity.The catalyst bed was created by discrete element method(DEM)and the central longitudinal section of the reactor tube was defined as the 2 D simulation region.Both of the homogeneous and catalytic heterogeneous chemical reactions were described by detailed micro-kinetics within the particle-resolved CFD simulation.At first,the established model of monolith reactors was verified by comparing the simulated results with experimental results reported in literature.Then,the effects of operation conditions and catalyst concentration on the ethylene selectivity in randomly packed beds were explored.The specific variation of certain operation conditions including inlet flow rate,inlet temperature,pressure,inlet C2 H6/O2 ratio and N2 dilution ratio can effectively increase ethylene selectivity.And the reduction of ratio of catalytic active area to geometric area Fcat/georepresenting catalyst properties from 140 to 30 increases the selectivity from 42.2%to 59.3%.This research can provide reference for the industrialization of ODHE process in the future.
基金Supported by Science and Technology Planning Project of Qinhuangdao City(201602A185)
文摘[Objectives] This study was conducted to determine in-vitro antibacterial effect of 58 Chinese herbs on Staphylococcus aureus,and screen single Chinese herbs with better in-vitro antibacterial effect for formulation of prescription. [Methods]Effective components in Chinese herbs were extracted with water,and inhibition zone diameters and minimal inhibitory concentrations of the 58 Chinese herbs against S. aureus were determined by agar plate punching method and micro two-fold method,respectively. [Results] Twenty two kinds of Chinese herbs including Terminalia chebula Retz.,Anemarrhena asphodeloides Bunge.,Prunella vulgaris L,Rheum palmatum L. and Mosla chinensis Maxim. had better antibacterial effect,among which T. chebula Retz.,A. asphodeloides Bunge.,P. vulgaris L,R. palmatum L. and C. sappan Linn showed the best antibacterial effect,with average inhibition zone over 20 mm and MIC lower than 15. 6 mg/ml.[Conclusions]Traditional Chinese herbs have certain antibacterial effect,and this study will provide important theoretical reference for clinical medication and development of prescription.
基金supported in part by Youth Innovation Promotion Association,Chinese Academy of Sciences,in part by Beijing Municipal Science&Technology Program under grant Z221100007722014in part by Zhejiang Key Research Program under grant 2021C01040.
文摘Dear Editor,Short-range wireless communications have been widely used in our daily life,but the pursuit of a better communication experience never stops,leading to the more stringent requirements of emerging applications.^(1)For example,remote control applications such as telesurgery require a delay of less than 1 ms.^(2)Indus-trial closed-loop control applications such as automatic assembly lines have a reliability requirement of at least 99.999%.