Rape bee pollen has attracted increasing interests for its excellent protective effect against chemicalinduced liver injury owing to its abundant polyphenols.This study aims to analyze the types and contents of phenol...Rape bee pollen has attracted increasing interests for its excellent protective effect against chemicalinduced liver injury owing to its abundant polyphenols.This study aims to analyze the types and contents of phenolamides(seldom concerned)in rape bee pollen and their protective mechanism on alcoholic liver disease(ALD).Different from the previous finding that flavonoids are dominant polyphenols in bee pollen polyphenolic extract,our results demonstrated that there are only three flavonoids but 24 phenolamides in the as-prepared rape bee pollen phenolic extract(PPE).In addition,PPE was found to significantly improve the viability(from 54.9%to 84.1%,89.2%,and 94.0%)of alcohol-induced AML12 cells and alleviate alcoholinduced cell apoptosis(from 28.5%to 22.89%,22.0%,and 17.4%).To dissect the underlying mechanism for the protective effect of PPE against ALD,the molecular pathway was identified by RNA-Seq analysis.Transcriptome data revealed that PPE may protect against ALD by decreasing inflammation,cholesterol,and fatty acid synthesis(P<0.05).The National Institute on Alcohol Abuse and Alcoholism(NIAAA)model was used to further evaluate the hepatoprotective effect of PPE in vivo,and the results validated that PPE could alleviate liver injury and hepatic steatosis(from 22.7%to 11.5%and 10.9%)induced by alcohol.As the dominant polyphenols in PPE,phenolamides can be a class of valuable polyphenolic compounds in bee pollen with the potential to alleviate ALD.展开更多
Our previous study has demonstrated that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A_(1))can prevent acrylamide(ACR)-induced cytotoxicity in small intestine cells.However,the potential mechanism re...Our previous study has demonstrated that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A_(1))can prevent acrylamide(ACR)-induced cytotoxicity in small intestine cells.However,the potential mechanism remains poorly understood.In this study,ACR treatment was found to increase the levels of 8-hydroxy deoxyguanine(8-OHdG)and phosphorated histone H_(2)AX(γH_(2)AX),two DNA damage markers,thereby resulting in cell cycle arrest in the G2/M phase;whereas both A_(1) and D-A_(1) could prevent the phosphorylation of ataxia telangiectasia mutated(ATM)and checkpoint kinase 2(Chk2),and then regulate the expression of G2/M phase-related proteins,finally maintaining normal cell cycle progression.Moreover,A_(1) and D-A_(1) could increase the B cell lymphoma 2(Bcl-2)/Bcl2-associated X(Bax)ratio and decrease the expression of cleaved caspase-3 and cleaved caspase-9 proteins to alleviate ACR-induced cell apoptosis,which might be related to the inhibition of the mitogen-activated protein kinase(MAPK)pathway.More importantly,A_(1) showed no remarkable variation in inhibitory effect before and after digestion,indicating that it can endure gastrointestinal digestion and may be a promising phytochemical to alleviate ACR-induced intestinal cell damage.展开更多
Objective:To study the effect of transcranial magnetic stimulation(TMS)on improving motor symptoms in patients with Parkinson’s disease(PD).Methods:60 PD patients who visited the hospital from September 2023 to Augus...Objective:To study the effect of transcranial magnetic stimulation(TMS)on improving motor symptoms in patients with Parkinson’s disease(PD).Methods:60 PD patients who visited the hospital from September 2023 to August 2024 were selected as samples and randomly divided into two groups.Group A received conventional medication plus TMS treatment,while Group B received medication only.The efficacy of motor function improvement,neurological symptoms,mental state,sleep quality,quality of life,and adverse reactions was compared between the two groups.Results:The efficacy of Group A was higher than that of Group B(P<0.05).The scores of the Scales for Outcomes in Parkinson’s Disease-Autonomic(SCOPA-AUT),Mini-Mental State Examination(MMSE),and Pittsburgh Sleep Quality Index(PSQI)in Group A were lower than those in Group B(P<0.05).The quality of life scale(SF-36)score in Group A was higher than that in Group B(P<0.05).The adverse reaction rate in Group A was lower than that in Group B(P<0.05).Conclusion:TMS used in the treatment of PD patients can improve patients’mental state and motor function,optimize sleep quality and quality of life,and is safe and efficient.展开更多
A simple procedure is described for the HPLC and UV determination of tea saponin in tea seed oil. Determinate was accomplished with UV wavelength detection 550 nm for saponification sample, and HPLC was done under con...A simple procedure is described for the HPLC and UV determination of tea saponin in tea seed oil. Determinate was accomplished with UV wavelength detection 550 nm for saponification sample, and HPLC was done under conditions: C18 analytical column of TC-C18, 4. 6 × 250 mm, column temperature at room temperature, injected sample volume was 10 μL, mobile phase’s methanol, flow-rate 0.8 ml/min and detection wavelength 280 nm.展开更多
Anodic oxygen evolution reaction(OER)is the key bottleneck for water electrolysis technique owing to its sluggish reaction kinetics.Interfacial engineering on the rationally designed heterostructure can regulate the e...Anodic oxygen evolution reaction(OER)is the key bottleneck for water electrolysis technique owing to its sluggish reaction kinetics.Interfacial engineering on the rationally designed heterostructure can regulate the electronic states efficiently for intrinsic activity improvement.Here,we report a co-phosphorization approach to construct a VPO_(4)-Ni_(2)P heterostructure on nickel foam with strongly chemical binding,wherein phosphate acts as electronic modifier for Ni_(2)P electrocatalyst.Profiting from the interfacial interaction,it is uncovered that electron shifts from Ni_(2)P to VPO_(4)to render valence increment in Ni species.Such an electronic manipulation rationalizes the chemical affinities of various oxygen intermediates in OER pathway,giving a substantially reduced energy barrier.As a result,the advanced VPO_(4)-Ni_(2)P heterostructure only requires an overpotential of 289 mV to deliver a high current density of 350 mA/cm^(2)for OER in alkaline electrolyte,together with a Tafel slope as low as 28 mV/dec.This work brings fresh insights into interfacial engineering for advanced electrocatalyst design.展开更多
Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In thi...Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.展开更多
Optical coherence tomography(OCT)enables in vivo imaging of port wine stains(PWS)lesions.The knowledge of vascular struct ure and epidermal thickness(ET)of PWS may aid the objectivediagnosis and optimal treatment.To o...Optical coherence tomography(OCT)enables in vivo imaging of port wine stains(PWS)lesions.The knowledge of vascular struct ure and epidermal thickness(ET)of PWS may aid the objectivediagnosis and optimal treatment.To obtain the structural parameters more rapidly and avoiduser intervention,an automated algorithm of energy map is introduced based on intensity andedge information to extract the skin surface using dynamic programming method.Subsequently,an averaged A-scan analysis is performed to obtain the mean ET and the relative intensity ofdermis indicating the corresponding vascular density.This approach is currently successfullyapplied in clinical diagnosis and shows promising guidance and assessment of PDT treatment.展开更多
Efficient catalytic system with low energy consumption exhibits increasing importance due to the upcoming energy crisis.Given this situation,it should be an admirable strategy for reducing energy input by effectively ...Efficient catalytic system with low energy consumption exhibits increasing importance due to the upcoming energy crisis.Given this situation,it should be an admirable strategy for reducing energy input by effectively utilizing incident solar energy as a heat source during catalytic reactions.Herein,aza-fused7 r-conjugated microporous polymer(aza-CMP)with broad light absorption and high photothermal conversion efficiency was synthesized and utilized as a support for bimetallic AuPd nanocatalysts in light-driven benzyl alcohol oxidation.The AuPd nanoparticles anchored on aza-CMP(aza-CM P/Au_xPdy)exhibited excellent catalytic performance for benzyl alcohol oxidation under 50 mW/cm^2 light irradiation.The improved catalytic performance by the aza-CMP/Au_xPdy is attributed to the unique photothermal effect induced by aza-CMP,which can promote the catalytic benzyl alcohol oxidation occurring at Au Pd.This work presents a novel approach to effectively utilize solar energy for conventional catalytic reactions through photothermal effect.展开更多
In this paper,we present a distal-scanning common path probe for optical coherence tomography(OCT)equipped with a hollow ultrasonic motor and a simple and specially designed beam-splitter.This novel probe proves to be...In this paper,we present a distal-scanning common path probe for optical coherence tomography(OCT)equipped with a hollow ultrasonic motor and a simple and specially designed beam-splitter.This novel probe proves to be able to effectively circumvent polarization and dispersion mismatch caused by fiber motion and is more robust to a variety of interfering factors during the imaging process,experimentally compared to a conventional noncommon path probe.Furthermore,our design counteracts the attenuation of backscattering with depth and the fall-off of the signal,resulting in a more balanced signal range and greater imaging depth.Spectral-domain OCT imaging of phantom and biological tissue is also demonstrated with a sensitivity of∼100dB and a lateral resolution of∼3μm.This low-cost probe offers simplified system configuration and excellent robustness,and is therefore particularly suitable for clinical diagnosis as one-off medical apparatus.展开更多
In most coherent imaging modality,speckle noise is a major cause that blurs the boundary of tissues and degrades the image contrast.By utilizing the unique properties of supercontinuum(SC)generated by noise-like pulse...In most coherent imaging modality,speckle noise is a major cause that blurs the boundary of tissues and degrades the image contrast.By utilizing the unique properties of supercontinuum(SC)generated by noise-like pulses(NLPs)and a simple multi-frame averaging technique,we achieved significant speckle reduction in spectral domain optical coherence tomography(SD-OCT).We quantitatively compared the speckle of our proposed method with those of conventional swept source OCT(SS-OCT)and SD-OCT based on commercial light sources.The experimental results show that SC pumped by NLPs combined with noncoherent averaging method achieves better denoising performance in terms of contrast to noise ratio(CNR).展开更多
In the process of Higher Vocational classified examination enrollment reform,Jilin Province has adopted a diversified examination enrollment model and“cultural quality test+vocational skill test”evaluation method,an...In the process of Higher Vocational classified examination enrollment reform,Jilin Province has adopted a diversified examination enrollment model and“cultural quality test+vocational skill test”evaluation method,and established the“vocational education college entrance examination”system.This paper analyzes the important role and practical difficulties of“vocational skill test”in Higher Vocational classified examination,studies the existing problems,and puts forward to reasonably divide the proportion of“cultural quality test”and“vocational skill test”,sets diversified admission standards,scientifically sets up the assessment methods and contents of“vocational skill test”,further improves the“cultural quality test+vocational skill test”evaluation method and builds a classified examination and enrollment system more in line with the characteristics of vocational education.展开更多
Aqueous Zn batteries(AZBs)suffer from poor Zn anode reversibility.To address this issue,excess Zn foil is often utilized to prolong the cycle life,but it reduces the actual battery energy density.In this work,we use m...Aqueous Zn batteries(AZBs)suffer from poor Zn anode reversibility.To address this issue,excess Zn foil is often utilized to prolong the cycle life,but it reduces the actual battery energy density.In this work,we use methylurea molecules to in situ form a solid electrolyte interphase(SEI)layer on the Zn anode,achieving reversible Zn plating/stripping with a maximal Coulombic efficiency(CE)of 99.99%and extending the anode's lifespan to 4500 cycles.Leveraging this highly reversible chemistry,we fabricate and test various anode-free Zn batteries.An anode-free Zn-AC cell exhibits stable cycling for exceeding 5000 cycles,an anode-free Zn-I_(2) battery with high specific capacities achieves a stable cycle life of 1000 cycles,and an anode-free Zn-Br_(2) battery with a high areal capacity of 4 mAh cm^(-2) demonstrates a stable cycle life of 450 cycles.Characterization of the SEI using TEM and DFT calculations reveal the formation mechanisms of the ZnCO_(3)-and ZnS-rich amorphous SEI layer.These results indicate that the design of desirable SEI compositions could pave the way for developing low-cost,high-performance anode-free AZBs.展开更多
Alzheimer’s disease(AD)is the leading cause of dementia worldwide.Traditionally,pathological studies have concentrated on the abnormal buildup of amyloid b(Ab)plaques and neurofibrillary tangles(NFTs),which arise fro...Alzheimer’s disease(AD)is the leading cause of dementia worldwide.Traditionally,pathological studies have concentrated on the abnormal buildup of amyloid b(Ab)plaques and neurofibrillary tangles(NFTs),which arise from the excessive phosphorylation of tau proteins in the brain1,2.Despite extensive research.展开更多
Traditional feeding strategy during lactation can result in nutrient deficiencies and negatively impact long-term productivity,compromising both the sustainability and profitability of the swine industry.Precision fee...Traditional feeding strategy during lactation can result in nutrient deficiencies and negatively impact long-term productivity,compromising both the sustainability and profitability of the swine industry.Precision feeding,supported by decision-making systems built on advanced predictive models,offers a promising solution to address these challenges.This study aimed to develop prediction models for weaning performance,focusing on key indicators such as weaned litter weight(WLW),weaned litter size(WLS),dry matter in milk(DMm),and nitrogen in milk(Nm).The models integrate farm management practices and feed nutrient composition,providing a data-driven framework for optimizing performance.A total of 10,089 observations were collected from 17 trial pig farms across eight provinces in China.Eleven statistical and machine learning(ML)regression algorithms were employed,incorporating stratified sampling and the recursive feature elimination method for feature selection.The findings demonstrated that the ensemble learning models,specifically random forest and gradient boosting decision tree regression,delivered the best overall performance,with a coefficient of determination(R2)ranging from 0.40 to 0.80 and a mean absolute error(MAE)between 0.11 and 4.36.The shapley additive explanations(SHAP)heatmap used for feature importance analysis revealed that,although the key predictors of weaning performance varied across models,this study newly identified lactation duration,birth litter weight,parity,and backfat thickness on the 7th day of lactation(L.d7BF)as consistently important features across different models.The discrepancies between correlation analysis and feature importance suggest the presence of non-linear relationships,feature interactions,and multicollinearity within the dataset.This study presents a novel framework that provides valuable insights into the factors influencing weaning performance under diverse management practices and feed nutrient conditions.The optimized prediction model can be employed to guide real-time sensor-based precision feeding systems,thereby enhancing efficiency and sustainability in swine production.展开更多
Heteroatom occupancy plays a key role in the precise modulation of specific material regions by introducing foreign elements into the main material matrix,yet it urgently requires further understanding from a spatial ...Heteroatom occupancy plays a key role in the precise modulation of specific material regions by introducing foreign elements into the main material matrix,yet it urgently requires further understanding from a spatial perspective.Herein,we propose a“satellite atom-spinel crystal”concept by synthesizing model catalysts with Fe atoms strategically positioned at two different spatial positions of spinel Co_(3)O_(4)(satellite-Fe at Co_(3)O_(4)(Fe_((Sat))-Co_(3)O_(4))and Fe-doped Co_(3)O_(4)(Co_(3)Fe(In)O_(4))),through which a new catalytic phenomenon is found.Multidimensional in situ spectroscopies revealed that Fe_((Sat))-Co_(3)O_(4) overcomes the crystal field potential energy(FeSat–O>FeSat–O–CoOh)and exhibits 1%(Fe atom)lower impedance than that of Co_(3)Fe(In)O_(4) due to the resistance-free electron delocalization layer formed in Fe_((Sat))-Co_(3)O_(4),which results in tens of times increase of the turnover frequency and mass activity and then a great reduction in the overpotential by 120 mV when used to catalyze the electrochemical oxygen evolution reaction compared to that of Co_(3)Fe(In)O_(4).Density functional theory calculations further dynamically reveal the mechanisms governing electron itinerancy modulation.This study not only provides valuable insights into the impact of heteroatomic spatial positioning on material properties but also significantly expands our understanding of atomic manipulation.展开更多
Formic acid oxidation is an important electrocatalytic reaction in proton- exchange membrane （PEM） fuel cells, in which both active sites and species adsorption/activation play key roles. In this study, we have deve...Formic acid oxidation is an important electrocatalytic reaction in proton- exchange membrane （PEM） fuel cells, in which both active sites and species adsorption/activation play key roles. In this study, we have developed hollow Pd-Ag alloy nanostructures with high active surface areas for application to electrocatalytic formic acid oxidation. When a certain amount of Ag is incorporated into a Pd lattice, which is already a highly active material for formic acid oxidation, the electrocatalytic activity can be significantly boosted. As indicated by theoretical simulations, coupling between Pd and Ag induces polarization charges on Pd catalytic sites, which can enhance the adsorption of HCO0＊ species. As a result, the designed electrocatalysts can achieve reduced Pd usage and enhanced catalytic properties at the same time. This study represents an approach that simultaneously fabricates hollow structures to increase the number of active sites and utilizes interatomic interactions to tune species adsorption/ activation towards improved electrocatalytic performance.展开更多
Atomically dispersed metal has gained much attention because of the new opportunities they offer in catalysis. However, it is still crucial to understand the mechanism of single-atom catalysis at molecular level for e...Atomically dispersed metal has gained much attention because of the new opportunities they offer in catalysis. However, it is still crucial to understand the mechanism of single-atom catalysis at molecular level for expanding them to other more difficult catalytic reactions, such as ammonia synthesis from nitrogen. In fact, developing ammonia synthesis under ambient conditions to overcome the high energy consumption in well-established Haber-Bosch process has fascinated scientists for many years.Herein, we demonstrate that single Cu atom yields facile valence-electron isolation from the conjugated π electron cloud of p-CN. Electron spin resonance measurements reveal that these isolated valence electrons can be easily excited to generate free electrons under photo-illumination, thus inducing high efficient photo-induced ammonia synthesis under ambient conditions.The NH_3 producing rate of copper modified carbon nitride(Cu-CN) reached 186 μmol g^(-1) h^(-1) under visible light irradiation with the quantum efficiency achieved 1.01% at 420 nm monochromatic light. This finding surely offers a model to open up a new vista for the ammonia synthesis at gentle conditions. The introduction of single atom to isolate the valence electron also represents a new paradigm for many other photocatalytic reactions, since the most photoinduced processes have been successfully exploited sharing the same origin.展开更多
To fully realize the commercial viability of Pt in fuel cells, the usage of scarce Pt must be reduced while the activity and durability in 02 reduction reaction （ORR） must be enhanced. Here we report a metallic stac...To fully realize the commercial viability of Pt in fuel cells, the usage of scarce Pt must be reduced while the activity and durability in 02 reduction reaction （ORR） must be enhanced. Here we report a metallic stack design achieving these goals for ORR, based on atomically precise materials synthesis. Au@Pd@Pt nanostructures with atomically thin Pt shells and high-index surfaces form an excellent platform for integrating the effects of electronic structures, surface facets, and substrate stabilization to boost ORR performance. Au@Pd@Pt trisoctahedrons （TOH） achieve mass activity 6.1 times higher than that of commercial Pt/C and dramatically enhanced durability beyond 1.0 V vs. a reversible hydrogen electrode in oxidation potential. Meanwhile, Pt comprises only 3.2% of the nanostructures. To further improve the ORR activity and demonstrate the versatility of our strategy, we implement the same design in PtNi alloy electrocatalysts. The Au@Pd@PtNi TOHs exhibit mass activity 14.3 times higher than that of commercial Pt/C as well as excellent durability. This work demonstrates an alternative strategy for fabricating high-performance and low-cost catalysts, and highlights the importance of simultaneous surface and interfacial engineering with atomic precision in designing catalysts.展开更多
基金supported by Key Research and Development Program of Hubei Province(2022BBA0072)Applied Fundamental Frontier Project of Wuhan Science and Technology Bureau(2020020601012271)。
文摘Rape bee pollen has attracted increasing interests for its excellent protective effect against chemicalinduced liver injury owing to its abundant polyphenols.This study aims to analyze the types and contents of phenolamides(seldom concerned)in rape bee pollen and their protective mechanism on alcoholic liver disease(ALD).Different from the previous finding that flavonoids are dominant polyphenols in bee pollen polyphenolic extract,our results demonstrated that there are only three flavonoids but 24 phenolamides in the as-prepared rape bee pollen phenolic extract(PPE).In addition,PPE was found to significantly improve the viability(from 54.9%to 84.1%,89.2%,and 94.0%)of alcohol-induced AML12 cells and alleviate alcoholinduced cell apoptosis(from 28.5%to 22.89%,22.0%,and 17.4%).To dissect the underlying mechanism for the protective effect of PPE against ALD,the molecular pathway was identified by RNA-Seq analysis.Transcriptome data revealed that PPE may protect against ALD by decreasing inflammation,cholesterol,and fatty acid synthesis(P<0.05).The National Institute on Alcohol Abuse and Alcoholism(NIAAA)model was used to further evaluate the hepatoprotective effect of PPE in vivo,and the results validated that PPE could alleviate liver injury and hepatic steatosis(from 22.7%to 11.5%and 10.9%)induced by alcohol.As the dominant polyphenols in PPE,phenolamides can be a class of valuable polyphenolic compounds in bee pollen with the potential to alleviate ALD.
基金supported by the project from National Natural Science Foundation of China(31671962)Excellent Youth Foundation of Education Department of Hunan Province(23B0229)Fundamental Research Funds for the Central Universities(2662019PY034).
文摘Our previous study has demonstrated that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A_(1))can prevent acrylamide(ACR)-induced cytotoxicity in small intestine cells.However,the potential mechanism remains poorly understood.In this study,ACR treatment was found to increase the levels of 8-hydroxy deoxyguanine(8-OHdG)and phosphorated histone H_(2)AX(γH_(2)AX),two DNA damage markers,thereby resulting in cell cycle arrest in the G2/M phase;whereas both A_(1) and D-A_(1) could prevent the phosphorylation of ataxia telangiectasia mutated(ATM)and checkpoint kinase 2(Chk2),and then regulate the expression of G2/M phase-related proteins,finally maintaining normal cell cycle progression.Moreover,A_(1) and D-A_(1) could increase the B cell lymphoma 2(Bcl-2)/Bcl2-associated X(Bax)ratio and decrease the expression of cleaved caspase-3 and cleaved caspase-9 proteins to alleviate ACR-induced cell apoptosis,which might be related to the inhibition of the mitogen-activated protein kinase(MAPK)pathway.More importantly,A_(1) showed no remarkable variation in inhibitory effect before and after digestion,indicating that it can endure gastrointestinal digestion and may be a promising phytochemical to alleviate ACR-induced intestinal cell damage.
文摘Objective:To study the effect of transcranial magnetic stimulation(TMS)on improving motor symptoms in patients with Parkinson’s disease(PD).Methods:60 PD patients who visited the hospital from September 2023 to August 2024 were selected as samples and randomly divided into two groups.Group A received conventional medication plus TMS treatment,while Group B received medication only.The efficacy of motor function improvement,neurological symptoms,mental state,sleep quality,quality of life,and adverse reactions was compared between the two groups.Results:The efficacy of Group A was higher than that of Group B(P<0.05).The scores of the Scales for Outcomes in Parkinson’s Disease-Autonomic(SCOPA-AUT),Mini-Mental State Examination(MMSE),and Pittsburgh Sleep Quality Index(PSQI)in Group A were lower than those in Group B(P<0.05).The quality of life scale(SF-36)score in Group A was higher than that in Group B(P<0.05).The adverse reaction rate in Group A was lower than that in Group B(P<0.05).Conclusion:TMS used in the treatment of PD patients can improve patients’mental state and motor function,optimize sleep quality and quality of life,and is safe and efficient.
文摘A simple procedure is described for the HPLC and UV determination of tea saponin in tea seed oil. Determinate was accomplished with UV wavelength detection 550 nm for saponification sample, and HPLC was done under conditions: C18 analytical column of TC-C18, 4. 6 × 250 mm, column temperature at room temperature, injected sample volume was 10 μL, mobile phase’s methanol, flow-rate 0.8 ml/min and detection wavelength 280 nm.
基金financially supported in part by National Key R&D Program of China(Nos.2020YFA0406103,2017YFA0207301)National Natural Science Foundation of China(Nos.21725102,91961106,U1832156,22075267,21803002)+4 种基金Science and Technological Fund of Anhui Province for Outstanding Youth(No.2008085J05)Youth Innovation Promotion Association of CAS(No.2019444)Young Elite Scientist Sponsorship Program by CAST,MOST(No.2018YFA0208603)Users with Excellence Program of Hefei Science Center CAS(No.2020HSC-UE003)Postdoc Matching Fund Scheme of the Hong Kong Polytechnic University(No.1-W144)。
文摘Anodic oxygen evolution reaction(OER)is the key bottleneck for water electrolysis technique owing to its sluggish reaction kinetics.Interfacial engineering on the rationally designed heterostructure can regulate the electronic states efficiently for intrinsic activity improvement.Here,we report a co-phosphorization approach to construct a VPO_(4)-Ni_(2)P heterostructure on nickel foam with strongly chemical binding,wherein phosphate acts as electronic modifier for Ni_(2)P electrocatalyst.Profiting from the interfacial interaction,it is uncovered that electron shifts from Ni_(2)P to VPO_(4)to render valence increment in Ni species.Such an electronic manipulation rationalizes the chemical affinities of various oxygen intermediates in OER pathway,giving a substantially reduced energy barrier.As a result,the advanced VPO_(4)-Ni_(2)P heterostructure only requires an overpotential of 289 mV to deliver a high current density of 350 mA/cm^(2)for OER in alkaline electrolyte,together with a Tafel slope as low as 28 mV/dec.This work brings fresh insights into interfacial engineering for advanced electrocatalyst design.
基金supported by the project from National Natural Science Foundation of China (31671962)Fundamental Research Funds for the Central Universities (2662019PY034)。
文摘Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.
基金supported in part by the National Natural Science Foundation of China under Grant 61227807by the Ministry of Science and Technology of China under contracts 2006AA02Z472,001CB510307 and 2009CB929400+1 种基金by the Ministryof Education of China Grant 20130002110079 for Doctoral Programby the Tsinghua Initiative Scientific Research Program Grant 2013THZ02-3.
文摘Optical coherence tomography(OCT)enables in vivo imaging of port wine stains(PWS)lesions.The knowledge of vascular struct ure and epidermal thickness(ET)of PWS may aid the objectivediagnosis and optimal treatment.To obtain the structural parameters more rapidly and avoiduser intervention,an automated algorithm of energy map is introduced based on intensity andedge information to extract the skin surface using dynamic programming method.Subsequently,an averaged A-scan analysis is performed to obtain the mean ET and the relative intensity ofdermis indicating the corresponding vascular density.This approach is currently successfullyapplied in clinical diagnosis and shows promising guidance and assessment of PDT treatment.
基金supported by National Key R&D Program of China (Nos.2017YFA0207301,2017YFA0207302)the National Natural Science Foundation of China (NSFC,Nos.21725102,21601173, U1832156,21881240040,21573212)+3 种基金CAS Key Research Program of Frontier Sciences (No.QYZDB-SSW-SLH018)CAS Interdisciplinary Innovation Team,and Chinese Universities Scientific Fund (No. WK2310000067)funded by Chinese Academy of Sciences President’s International Fellowship Initiative (No. 2019PC0114)support from USTC Center for Microand Nanoscale Research and Fabrication
文摘Efficient catalytic system with low energy consumption exhibits increasing importance due to the upcoming energy crisis.Given this situation,it should be an admirable strategy for reducing energy input by effectively utilizing incident solar energy as a heat source during catalytic reactions.Herein,aza-fused7 r-conjugated microporous polymer(aza-CMP)with broad light absorption and high photothermal conversion efficiency was synthesized and utilized as a support for bimetallic AuPd nanocatalysts in light-driven benzyl alcohol oxidation.The AuPd nanoparticles anchored on aza-CMP(aza-CM P/Au_xPdy)exhibited excellent catalytic performance for benzyl alcohol oxidation under 50 mW/cm^2 light irradiation.The improved catalytic performance by the aza-CMP/Au_xPdy is attributed to the unique photothermal effect induced by aza-CMP,which can promote the catalytic benzyl alcohol oxidation occurring at Au Pd.This work presents a novel approach to effectively utilize solar energy for conventional catalytic reactions through photothermal effect.
基金supported in part by the National Natural Science Foundation of China under Grants 61975091,61905015,61575108,and 61505034by the Tsinghua Precision Medicine Foundation and“Bio-Brain+X”Advanced Imaging Instrument Development Seed Grant.
文摘In this paper,we present a distal-scanning common path probe for optical coherence tomography(OCT)equipped with a hollow ultrasonic motor and a simple and specially designed beam-splitter.This novel probe proves to be able to effectively circumvent polarization and dispersion mismatch caused by fiber motion and is more robust to a variety of interfering factors during the imaging process,experimentally compared to a conventional noncommon path probe.Furthermore,our design counteracts the attenuation of backscattering with depth and the fall-off of the signal,resulting in a more balanced signal range and greater imaging depth.Spectral-domain OCT imaging of phantom and biological tissue is also demonstrated with a sensitivity of∼100dB and a lateral resolution of∼3μm.This low-cost probe offers simplified system configuration and excellent robustness,and is therefore particularly suitable for clinical diagnosis as one-off medical apparatus.
基金This research was supported by the National Natural Science Foundation of China(61227807,61575108 and 61505034)Tsinghua Initiative Scientific Research Program(2013THZ02-3)C.L.Pan and Y.J.You were supported in part by the Ministry of Science and Technology,Taiwan,under Grant 103-2622-E-007-006-CC2 and by the National Tsing Hua University Research Program Grant 104N2711E1.C.L.Pan is also supported by the Air Force Office of Scientific Research FA2386-13-1-4086.The first three authors contribute equally to this paper。
文摘In most coherent imaging modality,speckle noise is a major cause that blurs the boundary of tissues and degrades the image contrast.By utilizing the unique properties of supercontinuum(SC)generated by noise-like pulses(NLPs)and a simple multi-frame averaging technique,we achieved significant speckle reduction in spectral domain optical coherence tomography(SD-OCT).We quantitatively compared the speckle of our proposed method with those of conventional swept source OCT(SS-OCT)and SD-OCT based on commercial light sources.The experimental results show that SC pumped by NLPs combined with noncoherent averaging method achieves better denoising performance in terms of contrast to noise ratio(CNR).
基金This work was supported by the Social Science Project of the 13th Five-Year Plan of Jilin Provincial Department of Education under Grant no.JJKH20200635SKthe 2019 Vocational Education and Adult Education Teaching Reform Research Project of Jilin Provincial Department of Education under Grant nos.2019ZCZ067,2019ZCY413 and 2019ZCY414.
文摘In the process of Higher Vocational classified examination enrollment reform,Jilin Province has adopted a diversified examination enrollment model and“cultural quality test+vocational skill test”evaluation method,and established the“vocational education college entrance examination”system.This paper analyzes the important role and practical difficulties of“vocational skill test”in Higher Vocational classified examination,studies the existing problems,and puts forward to reasonably divide the proportion of“cultural quality test”and“vocational skill test”,sets diversified admission standards,scientifically sets up the assessment methods and contents of“vocational skill test”,further improves the“cultural quality test+vocational skill test”evaluation method and builds a classified examination and enrollment system more in line with the characteristics of vocational education.
基金support from the National Natural Science Foundation of China(52471242,92372122,21825302,22303094)the Fundamental Research Funds for the Central Universities(WK2060000040,KY2060000150,GG2060127001).
文摘Aqueous Zn batteries(AZBs)suffer from poor Zn anode reversibility.To address this issue,excess Zn foil is often utilized to prolong the cycle life,but it reduces the actual battery energy density.In this work,we use methylurea molecules to in situ form a solid electrolyte interphase(SEI)layer on the Zn anode,achieving reversible Zn plating/stripping with a maximal Coulombic efficiency(CE)of 99.99%and extending the anode's lifespan to 4500 cycles.Leveraging this highly reversible chemistry,we fabricate and test various anode-free Zn batteries.An anode-free Zn-AC cell exhibits stable cycling for exceeding 5000 cycles,an anode-free Zn-I_(2) battery with high specific capacities achieves a stable cycle life of 1000 cycles,and an anode-free Zn-Br_(2) battery with a high areal capacity of 4 mAh cm^(-2) demonstrates a stable cycle life of 450 cycles.Characterization of the SEI using TEM and DFT calculations reveal the formation mechanisms of the ZnCO_(3)-and ZnS-rich amorphous SEI layer.These results indicate that the design of desirable SEI compositions could pave the way for developing low-cost,high-performance anode-free AZBs.
基金supported by the National Natural Science Foundation of China(Grant No.32271220).
文摘Alzheimer’s disease(AD)is the leading cause of dementia worldwide.Traditionally,pathological studies have concentrated on the abnormal buildup of amyloid b(Ab)plaques and neurofibrillary tangles(NFTs),which arise from the excessive phosphorylation of tau proteins in the brain1,2.Despite extensive research.
基金supported by the National Key R&D Program(2021YFD1300401)the Excellent Youth Foundation of Hunan Province(2022JJ20027)the Science and Technology Major Project of Yunnan Province(202202AE090032).
文摘Traditional feeding strategy during lactation can result in nutrient deficiencies and negatively impact long-term productivity,compromising both the sustainability and profitability of the swine industry.Precision feeding,supported by decision-making systems built on advanced predictive models,offers a promising solution to address these challenges.This study aimed to develop prediction models for weaning performance,focusing on key indicators such as weaned litter weight(WLW),weaned litter size(WLS),dry matter in milk(DMm),and nitrogen in milk(Nm).The models integrate farm management practices and feed nutrient composition,providing a data-driven framework for optimizing performance.A total of 10,089 observations were collected from 17 trial pig farms across eight provinces in China.Eleven statistical and machine learning(ML)regression algorithms were employed,incorporating stratified sampling and the recursive feature elimination method for feature selection.The findings demonstrated that the ensemble learning models,specifically random forest and gradient boosting decision tree regression,delivered the best overall performance,with a coefficient of determination(R2)ranging from 0.40 to 0.80 and a mean absolute error(MAE)between 0.11 and 4.36.The shapley additive explanations(SHAP)heatmap used for feature importance analysis revealed that,although the key predictors of weaning performance varied across models,this study newly identified lactation duration,birth litter weight,parity,and backfat thickness on the 7th day of lactation(L.d7BF)as consistently important features across different models.The discrepancies between correlation analysis and feature importance suggest the presence of non-linear relationships,feature interactions,and multicollinearity within the dataset.This study presents a novel framework that provides valuable insights into the factors influencing weaning performance under diverse management practices and feed nutrient conditions.The optimized prediction model can be employed to guide real-time sensor-based precision feeding systems,thereby enhancing efficiency and sustainability in swine production.
基金supported by the National Natural Science Foundation of China(12405368,12135012)the Natural Science Foundation of Anhui Province(2408085QA016)the Scholarship from the China Scholarship Council(CSC)(202306340088)。
文摘Heteroatom occupancy plays a key role in the precise modulation of specific material regions by introducing foreign elements into the main material matrix,yet it urgently requires further understanding from a spatial perspective.Herein,we propose a“satellite atom-spinel crystal”concept by synthesizing model catalysts with Fe atoms strategically positioned at two different spatial positions of spinel Co_(3)O_(4)(satellite-Fe at Co_(3)O_(4)(Fe_((Sat))-Co_(3)O_(4))and Fe-doped Co_(3)O_(4)(Co_(3)Fe(In)O_(4))),through which a new catalytic phenomenon is found.Multidimensional in situ spectroscopies revealed that Fe_((Sat))-Co_(3)O_(4) overcomes the crystal field potential energy(FeSat–O>FeSat–O–CoOh)and exhibits 1%(Fe atom)lower impedance than that of Co_(3)Fe(In)O_(4) due to the resistance-free electron delocalization layer formed in Fe_((Sat))-Co_(3)O_(4),which results in tens of times increase of the turnover frequency and mass activity and then a great reduction in the overpotential by 120 mV when used to catalyze the electrochemical oxygen evolution reaction compared to that of Co_(3)Fe(In)O_(4).Density functional theory calculations further dynamically reveal the mechanisms governing electron itinerancy modulation.This study not only provides valuable insights into the impact of heteroatomic spatial positioning on material properties but also significantly expands our understanding of atomic manipulation.
文摘Formic acid oxidation is an important electrocatalytic reaction in proton- exchange membrane （PEM） fuel cells, in which both active sites and species adsorption/activation play key roles. In this study, we have developed hollow Pd-Ag alloy nanostructures with high active surface areas for application to electrocatalytic formic acid oxidation. When a certain amount of Ag is incorporated into a Pd lattice, which is already a highly active material for formic acid oxidation, the electrocatalytic activity can be significantly boosted. As indicated by theoretical simulations, coupling between Pd and Ag induces polarization charges on Pd catalytic sites, which can enhance the adsorption of HCO0＊ species. As a result, the designed electrocatalysts can achieve reduced Pd usage and enhanced catalytic properties at the same time. This study represents an approach that simultaneously fabricates hollow structures to increase the number of active sites and utilizes interatomic interactions to tune species adsorption/ activation towards improved electrocatalytic performance.
基金supported by the National Key R&D Program of China (2017YFA0207301)the National Natural Science Foundation of China (21622107, 11621063, U1532265)+2 种基金the Key Research Program of Frontier Sciences (QYZDY-SSW-SLH011), the Youth Innovation Promotion Association CAS (2016392)the Fundamental Research Funds of Central University (WK2340000075)the Major Program of Development Foundation of Hefei Center for Physical Science and Technology (2017FXZY003)
文摘Atomically dispersed metal has gained much attention because of the new opportunities they offer in catalysis. However, it is still crucial to understand the mechanism of single-atom catalysis at molecular level for expanding them to other more difficult catalytic reactions, such as ammonia synthesis from nitrogen. In fact, developing ammonia synthesis under ambient conditions to overcome the high energy consumption in well-established Haber-Bosch process has fascinated scientists for many years.Herein, we demonstrate that single Cu atom yields facile valence-electron isolation from the conjugated π electron cloud of p-CN. Electron spin resonance measurements reveal that these isolated valence electrons can be easily excited to generate free electrons under photo-illumination, thus inducing high efficient photo-induced ammonia synthesis under ambient conditions.The NH_3 producing rate of copper modified carbon nitride(Cu-CN) reached 186 μmol g^(-1) h^(-1) under visible light irradiation with the quantum efficiency achieved 1.01% at 420 nm monochromatic light. This finding surely offers a model to open up a new vista for the ammonia synthesis at gentle conditions. The introduction of single atom to isolate the valence electron also represents a new paradigm for many other photocatalytic reactions, since the most photoinduced processes have been successfully exploited sharing the same origin.
文摘To fully realize the commercial viability of Pt in fuel cells, the usage of scarce Pt must be reduced while the activity and durability in 02 reduction reaction （ORR） must be enhanced. Here we report a metallic stack design achieving these goals for ORR, based on atomically precise materials synthesis. Au@Pd@Pt nanostructures with atomically thin Pt shells and high-index surfaces form an excellent platform for integrating the effects of electronic structures, surface facets, and substrate stabilization to boost ORR performance. Au@Pd@Pt trisoctahedrons （TOH） achieve mass activity 6.1 times higher than that of commercial Pt/C and dramatically enhanced durability beyond 1.0 V vs. a reversible hydrogen electrode in oxidation potential. Meanwhile, Pt comprises only 3.2% of the nanostructures. To further improve the ORR activity and demonstrate the versatility of our strategy, we implement the same design in PtNi alloy electrocatalysts. The Au@Pd@PtNi TOHs exhibit mass activity 14.3 times higher than that of commercial Pt/C as well as excellent durability. This work demonstrates an alternative strategy for fabricating high-performance and low-cost catalysts, and highlights the importance of simultaneous surface and interfacial engineering with atomic precision in designing catalysts.
