The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds.Accurately obtaining the entrainment rate(λ)is particularly important for its parameteri...The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds.Accurately obtaining the entrainment rate(λ)is particularly important for its parameterization within the overall cumulus parameterization scheme.In this study,an improved bulk-plume method is proposed by solving the equations of two conserved variables simultaneously to calculateλof cumulus clouds in a large-eddy simulation.The results demonstrate that the improved bulk-plume method is more reliable than the traditional bulk-plume method,becauseλ,as calculated from the improved method,falls within the range ofλvalues obtained from the traditional method using different conserved variables.The probability density functions ofλfor all data,different times,and different heights can be well-fitted by a log-normal distribution,which supports the assumed stochastic entrainment process in previous studies.Further analysis demonstrate that the relationship betweenλand the vertical velocity is better than other thermodynamic/dynamical properties;thus,the vertical velocity is recommended as the primary influencing factor for the parameterization ofλin the future.The results of this study enhance the theoretical understanding ofλand its influencing factors and shed new light on the development ofλparameterization.展开更多
Elevated intraocular pressure(IOP)is one of the causes of retinal ischemia/reperfusion injury,which results in NRP3 inflammasome activation and leads to visual damage.Homerla is repo rted to play a protective role in ...Elevated intraocular pressure(IOP)is one of the causes of retinal ischemia/reperfusion injury,which results in NRP3 inflammasome activation and leads to visual damage.Homerla is repo rted to play a protective role in neuroinflammation in the cerebrum.However,the effects of Homerla on NLRP3inflammasomes in retinal ischemia/reperfusion injury caused by elevated IOP remain unknown.In our study,animal models we re constructed using C57BL/6J and Homer1^(flox/-)/Homerla^(+/-)/Nestin-Cre^(+/-)mice with elevated IOP-induced retinal ischemia/repe rfusion injury.For in vitro expe riments,the oxygen-glucose deprivation/repe rfusion injury model was constructed with M uller cells.We found that Homerla ove rexpression amelio rated the decreases in retinal thickness and Muller cell viability after ischemia/reperfusion injury.Furthermore,Homerla knockdown promoted NF-κB P65^(Ser536)activation via caspase-8,NF-κB P65 nuclear translocation,NLRP3 inflammasome formation,and the production and processing of interleukin-1βand inte rleukin-18.The opposite results we re observed with Homerla ove rexpression.Finally,the combined administration of Homerla protein and JSH-23 significantly inhibited the reduction in retinal thickness in Homer1^(flox/-)Homer1a^(+/-)/Nestin-Cre^(+/-)mice and apoptosis in M uller cells after ischemia/reperfusion injury.Taken together,these studies demonstrate that Homer1a exerts protective effects on retinal tissue and M uller cells via the caspase-8/NF-KB P65/NLRP3 pathway after I/R injury.展开更多
Objective: Digital healthcare is rapidly becoming a new model for medical development in the information society with its convenience, and personalization, and a research boom in digital healthcare has formed at home ...Objective: Digital healthcare is rapidly becoming a new model for medical development in the information society with its convenience, and personalization, and a research boom in digital healthcare has formed at home and abroad in recent years. The purpose of this study is to conduct a bibliometric analysis of the field of digital healthcare and to understand the research background and development trend in this field. Methods: A visual analysis of authors, institutions, journals and keywords was conducted using CiteSpace 5.8R3 software. Results: A total of 1646 digital healthcare-related retrieved from WoS and PubMed studies. There was an overall upward trend in the number of digital healthcare publications, with the highest number of publications in 2021 (290). The author AZIZ SHEIKH is ranked first in the number of published articles (13), while King Saud University (23) is the research institution with the most articles. Keyword clustering showed that the first cluster was data security;the common high frequency keywords that appeared were systems (85), artificial intelligence (82), mobile health (70), internet (61), and technology (57). Digital healthcare, artificial intelligence, healthcare services, machine learning and deep learning are the hotspot of current research. Conclusion: This paper summarises the state of the art in digital healthcare research. Using statistical analysis and network visualisation, it highlights the background, trends and hot topics in digital healthcare research. The paper finds that there is significant potential for artificial intelligence to help bridge the digital divide and reduce health inequalities. To understand the current state, hot trends and future directions of digital healthcare research, this paper can serve as a reference. .展开更多
Consumption of shellfish contaminated with algal toxins produced by marine dinoflagellates can lead to diarrhetic shellfish poisoning (DSP). It was therefore essential that there are analytical techniques to identify ...Consumption of shellfish contaminated with algal toxins produced by marine dinoflagellates can lead to diarrhetic shellfish poisoning (DSP). It was therefore essential that there are analytical techniques to identify and quantify DSP toxins in shellfish. This new methodology could facilitate DSP monitoring and create a means of rapidly responding to incidents threatening public health. In the last years there were different analytical methods for DSP, such as mouse bioassay and LC-FLD. With the development of instrument, Liquid chromatography-mass spectrometry was substituted for other analytical methods with its good sensitivity and selectivity and without derivatization for the determination of DSP. In this report, a high performance liquid chromatogra-phytandem mass spectrometric(HPLC-MS/MS)method was developed for the simultaneous determination of okadaic acid (OA) and dinophysistoxins(DTX1) in Sinonovacula constricta. Optimization of pretreatment experiment was carried out to maximize recoveries and the effectiveness. The analytes were determined under multi-reactions monitoring (MRM) scan type with tandem mass analyzer using negative ion electrospray ionization (-ESI) mode .Finally, the detection and identification of OA and DTX-1 were based upon their retention times (RT) and the fragmentation patterns of their mass spectra. The method of LOQ for the two poisons was 0.02 mg·kg-1.The real sample test showed that this method could be used for sensitive, fast, and accurate determination of the two diarrheic shellfish poisons in shellfish.展开更多
Retinal injury after blunt ocular trauma may directly affect prognosis and lead to vision loss.To investigate the pathological changes and molecular mechanisms involved in retinal injury after blunt ocular trauma,we e...Retinal injury after blunt ocular trauma may directly affect prognosis and lead to vision loss.To investigate the pathological changes and molecular mechanisms involved in retinal injury after blunt ocular trauma,we established a weight drop injury model of blunt ocular trauma in male Beagle dogs.Hematoxylin-eosin staining,immunofluorescence staining,western blotting,and TUNEL assays were performed to investigate retinal injury within 14 days after blunt ocular trauma.Compared with the control group,the thicknesses of the inner and outer nuclear layers,as well as the number of retinal ganglion cells,gradually decreased within 14 days after injury.The number of bipolar cells in the inner nuclear layer began to decrease 1 day after injury,while the numbers of cholinergic and amacrine cells in the inner nuclear layer did not decrease until 7 days after injury.Moreover,retinal cell necroptosis increased with time after injury;it progressed from the ganglion cell layer to the outer nuclear layer.Visual electrophysiological findings indicated that visual impairment began on the first day after injury and worsened over time.Additionally,blunt ocular trauma induced nerve regeneration and Müller glial hyperplasia;it also resulted in the recruitment of microglia to the retina and polarization of those microglia to the M1 phenotype.These findings suggest that necroptosis plays an important role in exacerbating retinal injury after blunt ocular trauma via gliosis and neuroinflammation.Such a role has important implications for the development of therapeutic strategies.展开更多
We used the Integrated Biological Responses version 2(IBRv2)method to evaluate the biological eff ects of heavy metals in the sediments in Laizhou Bay,China on the benthic goby Acanthogobius ommaturus.In December 2018...We used the Integrated Biological Responses version 2(IBRv2)method to evaluate the biological eff ects of heavy metals in the sediments in Laizhou Bay,China on the benthic goby Acanthogobius ommaturus.In December 2018,gobies and sediments were collected from 15 stations.We measured the activities of defense enzymes and the contents of malondialdehyde(MDA)and metallothionein(MT)in the goby liver as well as the levels of heavy metals in the sediments and goby muscle tissue.Most of the heavy metal concentrations in sediment at each station were below the Class I criteria set by Chinese Standards for Marine Sediment Quality,and the Håkanson ecological risk index suggested low risk for the heavy metals.We found that A.ommaturus could eff ectively accumulate mercury,cadmium,arsenic,and zinc and that the contents of MT and MDA and the activities of glutathione peroxidase and glutathione reductase were suitable biomarkers of heavy metal pollution in this species.The IBRv2 method integrated these four biomarkers and discriminated stations according to heavy metal pollution.Higher IBRv2 values suggested more adverse eff ects in gobies,corroborating more serious heavy metal contamination.The stations with high IBRv2 values and high contents of heavy metals were mainly distributed in the west and northeast parts of the bay.These results show that the IBRv2 approach is a feasible strategy for assessing heavy metal pollution through biological response and biological status and that it can be implemented for environmental monitoring in Laizhou Bay.展开更多
This work develops 2-Phenyl-1H-imidazole-1-sulfonate(PHIS)as a multi-functional electrolyte additive for H2O/HF scavenging and film formation to improve the high temperature performance of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_...This work develops 2-Phenyl-1H-imidazole-1-sulfonate(PHIS)as a multi-functional electrolyte additive for H2O/HF scavenging and film formation to improve the high temperature performance of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/graphite batteries.After 450 cycles at room temperature(25℃),the discharge capacity retentions of batteries with blank and PHIS-containing electrolyte are 56.03%and 94.92%respectively.After 230 cycles at high temperatures(45℃),their values are 75.30%and 88.38%respectively.The enhanced electrochemical performance of the batteries with PHIS-containing electrolyte is supported by the spectroscopic characterization and theoretical calculations.It is demonstrated that this PHIS electrolyte additive can facilitate the construction of the electrode interface films,remove the H2O/HF in the electrolyte,and improve the electrochemical performance of the batteries.This work not only develops a sulfonate-based electrolyte but also can stimulate new ideas of functional additives to improve the battery performance.展开更多
The aim of this study was to investigate whether punicalagin(PU)could prevent obesity-related cardiac dysfunction by promoting DNA demethy lation,and to explore its possible mechanism.C57BL/6J mice were fed with stand...The aim of this study was to investigate whether punicalagin(PU)could prevent obesity-related cardiac dysfunction by promoting DNA demethy lation,and to explore its possible mechanism.C57BL/6J mice were fed with standard diet,high-fat diet(HFD),HFD supplemented with resveratrol,low-dose PU(LPU)and high-dose PU(HPU)for 8 weeks.Compared with HFD group,body weight was significantly lower in PU treatment groups,number of cardionwocytes and the protein level of myosin heavy chain 7B were significantly higher in PU treatment groups.Levels of 5-hydroxymethylcytosine and 5-formylcytosine were significantly lower in HFD group than in other groups.Compared with the HFD group,the protein level of ten-eleven translocation enzyme(TET)2 was significantly higher in PU treatment groups,p-AMP-activated protein kinase(AMPK)was significantly higher in LPU group.Levels of total antioxidant capacity and the protein levels of complexesⅡ/Ⅲ/Ⅴ,oxoglutarate dehydrogenase,succinate dehydrogenase B and fumarate hdrolase were significantly lower in HFD group than PU treatment group.The ratio of(succinic acid+fumaric acid)/a-ketoglutarate was significantly higher in HFD group than other groups.In conclusion,PU up-regulated TETs enzyme activities and TET2 protein stability through alleviating mitochondrial dysfunction and activating AMPK,so as to promote DNA demethylation,thus preventing obesity-related cardiac dysfunction.展开更多
Plasma nitrogen fixation(PNF)has been emerging as a promising technology for greenhouse gasfree and renewable energy-based agriculture.Yet,most PNF studies seldom address practical application-specific issues.In this ...Plasma nitrogen fixation(PNF)has been emerging as a promising technology for greenhouse gasfree and renewable energy-based agriculture.Yet,most PNF studies seldom address practical application-specific issues.In this work,we present the development of a compact and automatic PNF system for on-site agricultural applications.The system utilized a gliding-arc discharge as the plasma source and employed a dual-loop design to generate NO_(x)from air and water under atmospheric conditions.Experimental results showed that the system with a dualloop design performs well in terms of energy costs and production rates.Optimal operational parameters for the system were determined through experimentation,resulting in an energy cost of 13.9 MJ mol^(-1)and an energy efficiency of 16 g kWh^(-1)for NO_(3)^(-)production,respectively.Moreover,the concentration of exhausted NO_(x)was below the emission standards.Soilless lettuce cultivation experiments demonstrated that NO_(x)^(-)produced by the PNF system could serve as liquid nitrate nitrogen fertilizer.Overall,our work demonstrates the potential of the developed PNF system for on-site application in the production of green-leaf vegetables.展开更多
BACKGROUND Oral implant surgery is an effective procedure for artificial implants in missing tooth areas under local anesthesia.Because patients under local anesthesia are conscious during this procedure,compared with...BACKGROUND Oral implant surgery is an effective procedure for artificial implants in missing tooth areas under local anesthesia.Because patients under local anesthesia are conscious during this procedure,compared with general anesthesia-related operations,they are more likely to experience negative emotions,such as anxiety and tension.These emotional reactions result in shivering and chills in the limbs,leading to poor doctor-patient cooperation and even avoidance of treatment.In traditional Chinese medicine,it is believed that acupoint massage regulates blood and Qi,dredge menstruation,and relieve pain,which is beneficial for patients’emotional adjustment;however,there are few related clinical studies.AIM To observe the changes in anxiety and pain in patients with oral implant after acupoint massage combined with touch therapy.METHODS One hundred patients undergoing oral implantation in our hospital between May 2020 and May 2023 were randomly divided into control and study groups,according to a random number table,with 50 patients in each group.The control group received routine intervention,and the study group received acupoint massage combined with touch on the basis of the control group.Anxiety[assessed using the Modified Dental Anxiety Scale(MDAS)],pain severity,blood pressure,heart rate,and satisfaction were compared between the two groups.RESULTS Before intervention,the difference in MDAS score between the two groups was not significant(P>0.05),while after the intervention,the MDAS scores decreased in both groups compared with those before the intervention(P<0.05);the MDAS score of the study group was lower than that of the control group,with a statistically significant difference(P<0.05).The degree of pain in the intervention group was significantly lower than that in the control group(P<0.05).Before the intervention,there were no significant differences in systolic and diastolic blood pressures or heart rate between the two groups(P>0.05).The systolic and diastolic blood pressures and heart rate in the intervention group,during and after the intervention,were significantly lower than those in the control group(P<0.05).The total degree of satisfaction in the study group was significantly higher than that in the control group(P<0.05).CONCLUSION Acupoint massage combined with touch better relieves anxiety and pain in patients undergoing dental implant surgery,improving the perioperative comfort of these patients and ensuring safety and a smooth operation.展开更多
[Objectives]To study the anti-inflammatory effect of Elephantopus scaber L.extract on acute pleurisy induced by carrageenan in rats,and to explore its anti-inflammatory mechanism.[Methods]The active sites of E.scaber ...[Objectives]To study the anti-inflammatory effect of Elephantopus scaber L.extract on acute pleurisy induced by carrageenan in rats,and to explore its anti-inflammatory mechanism.[Methods]The active sites of E.scaber L.were extracted by ethanol reflux method.The extracts of different concentrations of E.scaber L.were used as the study object,and dexamethasone was used as the positive control drug.The anti-inflammatory effects of E.scaber L.extracts were studied by measuring the levels of malondialdehyde(MDA),prostaglandin E_(2)(PGE_(2)),tumor necrosis factor(TNF-α),interleukin-1β(IL-1β)in pleural fluid and serum nitric oxide(NO),MDA,PEG_(2),TNF-α,IL-1βin rats with acute pleurisy induced by carrageenan.[Results]E.scaber L.extracts in three doses could reduce the levels of inflammatory factors in pleural fluid and serum,and inhibit acute pleurisy in rats.It was speculated that the anti-inflammatory mechanism was related to the inhibition of the release of inflammatory factors and the antioxidant effect of extracts of three doses of E.scaber L.[Conclusions]This experiment provides a basis for the development and application of E.scaber L.展开更多
AIM: To characterize the histochemical type and pattern of intestinal metaplasia (IM) adjacent to gastric cardia adenocarcinoma (GCA) and distal gastric cancer (GC) in Linzhou, Henan Province, China.METHODS: Alcian-bl...AIM: To characterize the histochemical type and pattern of intestinal metaplasia (IM) adjacent to gastric cardia adenocarcinoma (GCA) and distal gastric cancer (GC) in Linzhou, Henan Province, China.METHODS: Alcian-blue-periodic acid Schiff and high iron diamine-Alcian blue histochemical methods were performed on 142 cases of IM, including 49 cases of GCA and 93 cases of GC. All the patients were from Linzhou, Henan Province, China, the highest incidence area for both GCA and squamous cell carcinoma. Radio- or chemotherapy was not applied to these patients before surgery.RESULTS: The detection rate of IM in tissues adjacent to GCA tissues was 44.9%, which was significantly lower than that in GC tissues (80.64%, P<0.01). The rates of both incomplete small intestinal and colonic IM types identified by histochemistry in GCA tissues (31.82% and 63.64%, respectively) were significantly higher than those in GC (5.33% and 21.33%, respectively, P<0.01).CONCLUSION: IM in GCA and GC should be considered as a separate entity. Further research is needed to evaluate whether neoplastic progression of IM is related to its mucin profile in GCA.展开更多
Synthetic Aperture Radar(SAR)interferometry is one of the most powerful remote sensing tools for ground deformation detection.However,tropospheric delay greatly limits the measurement accuracy of the InSAR technique.W...Synthetic Aperture Radar(SAR)interferometry is one of the most powerful remote sensing tools for ground deformation detection.However,tropospheric delay greatly limits the measurement accuracy of the InSAR technique.While vertically stratified tropospheric delays have been extensively investigated and well tackled,turbulent tropospheric phase noise still remains an intractable issue.In recent years,great efforts have been made to reduce the influence of turbulent atmospheric delay.This contribution is intended to provide a systematic review of the progress achieved in this field.First,it introduces the physical characteristics of atmospheric signals in interferograms.Then,a review of the main mitigation algorithms proposed in the literature is provided.In addition,the strengths and weaknesses of each approach are analyzed to provide guidance for choosing a suitable method accordingly.Finally,sug-gestions for resolving the challenging issues and an outlook for future research are given.展开更多
BACKGROUND:This study aims to explore the characteristics of the epithelial-to-mesenchymal transition(EMT)process and its underlying molecular mechanisms in the period of paraquat(PQ)-induced pulmonary fi brosis(PF).M...BACKGROUND:This study aims to explore the characteristics of the epithelial-to-mesenchymal transition(EMT)process and its underlying molecular mechanisms in the period of paraquat(PQ)-induced pulmonary fi brosis(PF).METHODS:Picrosirius red staining and collagen volume fraction were utilized to evaluate the pathological changes of PQ-induced PF in rats.Immunohistochemistry,Western blot,and real-time reverse transcriptase-polymerase chain reaction(RT-PCR)were used to measure the protein and gene expression of EMT markers,EMT-associated transcription factors,and regulators of EMT-related pathways,respectively.RESULTS:The collagen deposition in the alveolar septum and increased PF markers were characteristics of pathological changes in PQ-induced PF,reached a peak on day 14 after PQ poisoning,and then decreased on day 21.The protein and gene expression of the fibrosis marker,EMT markers,transcription factors,and regulators of EMT-related signaling pathways signifi cantly increased at diff erent time points after PQ poisoning compared with corresponding controls(P<0.05),and most of them reached a peak on day 14,followed by a decrease on day 21.The gene expression of EMT markers was significantly correlated with PF markers,transcription factors,and regulators of EMT-related signaling pathways(P<0.05).The mRNA expression of transcription factors was signifi cantly correlated with that of TGF-β1 and Smad2(P<0.05 or P<0.01),instead of Wnt2 andβ-catenin(P>0.05).CONCLUSIONS:EMT process plays a role in the PQ-induced PF,in which most PF and EMT markers have a peak phenomenon,and its underlying molecular mechanisms might be determined by further studies.展开更多
Paeoniflorin (PF) is one of the main bioactive components of total glucosides of paeony (TGP) extracted from the root of Paeonia lactiflora Pall. TGP exhibit various biological activities such as improvement in memory...Paeoniflorin (PF) is one of the main bioactive components of total glucosides of paeony (TGP) extracted from the root of Paeonia lactiflora Pall. TGP exhibit various biological activities such as improvement in memory, hepatoprotection, antimutagenic properties and platelet aggregation inhibition. The aim of this paper is to review the pharmacokinetics (PK) of PF as a pure compound and in single or multiple herb(s) of traditional Chinese medicine (TCM) prescriptions. The distribution of PF or PF in TCM fitted one or two compartmental model after oral administration or intravenous injection, respectively. However, PF has a low bioavailability (BA) in rabbit (7.24%) and rat (3.24%) after oral administration. The PK profiles and BA of PF were remarkably improved when co-administered with sinomenine or glycyrrhizin acid. The PK profiles and BA of PF in Radix Paeonia Rubra (RP-R) and Jing-zhi guan-xin were improved, but in co-administration of RP-R with Radix Angelicae Sinensis, the BA was significantly reduced. PK profiles and BA of PF in Shan yao gan-cao tang or Danggui-Shaoyao-San was either remarkably improved or not. However, neither the PK profiles nor the BA of PF in Radix paeonia alba, Huangqin-tang Si ni san or Tang-Min-Ling-Wan was improved. Metabolism in the liver did not play any role in the low oral BA of PF. The low BA was thus attributed to poor permeation due to low lipophilicity, P-glycoprotein mediated efflux, intestinal bacteria and hydrolytic degradation in the intestine by the intestinal brush border lactase phlorizin hydrolase (LPH) and certain esterases. These findings show the in vivo course of PF and provide information on the maximum biological actions of PF that may help traditional Chinese herbal medicinal practitioners.展开更多
The circadian clock participates in maintaining homeostasis in peripheral tissues,including intervertebral discs(IVDs).Abnormal mechanical loading is a known risk factor for intervertebral disc degeneration(IDD).Based...The circadian clock participates in maintaining homeostasis in peripheral tissues,including intervertebral discs(IVDs).Abnormal mechanical loading is a known risk factor for intervertebral disc degeneration(IDD).Based on the rhythmic daily loading pattern of rest and activity,we hypothesized that abnormal mechanical loading could dampen the IVD clock,contributing to IDD.Here,we investigated the effects of abnormal loading on the IVD clock and aimed to inhibit compression-induced IDD by targeting the core clock molecule brain and muscle Arnt-like protein-1(BMAL1).In this study,we showed that BMAL1 KO mice exhibit radiographic features similar to those of human IDD and that BMAL1 expression was negatively correlated with IDD severity by systematic analysis based on 149 human IVD samples.The intrinsic circadian clock in the IVD was dampened by excessive loading,and BMAL1 overexpression by lentivirus attenuated compression-induced IDD.Inhibition of the RhoA/ROCK pathway by Y-27632 or melatonin attenuated the compression-induced decrease in BMAL1 expression.Finally,the two drugs partially restored BMAL1 expression and alleviated IDD in a diurnal compression model.Our results first show that excessive loading dampens the circadian clock of nucleus pulposus tissues via the RhoA/ROCK pathway,the inhibition of which potentially protects against compression-induced IDD by preserving BMAL1 expression.These findings underline the importance of the circadian clock for IVD homeostasis and provide a potentially effective therapeutic strategy for IDD.展开更多
The lithium-sulfur(Li-S)battery is one of the most promising substitutes for current energy storage systems because of its low cost,high theoretical capacity,and high energy density.However,the high solubility of inte...The lithium-sulfur(Li-S)battery is one of the most promising substitutes for current energy storage systems because of its low cost,high theoretical capacity,and high energy density.However,the high solubility of intermediate products(i.e.,lithium polysulfides)and the resultant shuttle effect lead to rapidly fading capacity and a low coulombic efficiency,which hinder the practical application of Li-S batteries.In this study,block copolymers are constructed with both an ethylene oxide unit and a styrene unit and then used as binders for Li-S batteries.Electrochemical performance improvements are attributed to the synergistic effects contributed by the different units of the block copolymer.The ethylene oxide unit traps polysulfide,which bonds strongly with the intermediate lithium polysulfide,and enhances the transport of lithium ions to reach high capacity.Meanwhile,the styrene unit maintains cathode integrity by improving the mechanical properties and elasticity of the constructed block copolymer to accommodate the large volume changes.By enabling multiple functions via different units in the polymer chain,high sulfur utilization is achieved,polysulfide diffusion is confined,and the shuttle effect is suppressed during the cycle life of Li-S batteries,as revealed by operando ultraviolet-visible spectroscopy and S Kedge X-ray absorption spectroscopy.展开更多
Two-dimensional(2D) layered perovskites have emerged as potential alternates to traditional three-dimensional(3D)analogs to solve the stability issue of perovskite solar cells. In recent years, many efforts have been ...Two-dimensional(2D) layered perovskites have emerged as potential alternates to traditional three-dimensional(3D)analogs to solve the stability issue of perovskite solar cells. In recent years, many efforts have been spent on manipulating the interlayer organic spacing cation to improve the photovoltaic properties of Dion–Jacobson(DJ) perovskites. In this work, a serious of cycloalkane(CA) molecules were selected as the organic spacing cation in 2D DJ perovskites, which can widely manipulate the optoelectronic properties of the DJ perovskites. The underlying relationship between the CA interlayer molecules and the crystal structures, thermodynamic stabilities, and electronic properties of 58 DJ perovskites has been investigated by using automatic high-throughput workflow cooperated with density-functional(DFT) calculations.We found that these CA-based DJ perovskites are all thermodynamic stable. The sizes of the cycloalkane molecules can influence the degree of inorganic framework distortion and further tune the bandgaps with a wide range of 0.9–2.1 eV.These findings indicate the cycloalkane molecules are suitable as spacing cation in 2D DJ perovskites and provide a useful guidance in designing novel 2D DJ perovskites for optoelectronic applications.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.42175099,42027804,42075073)the Innovative Project of Postgraduates in Jiangsu Province in 2023(Grant No.KYCX23_1319)+3 种基金supported by the National Natural Science Foundation of China(Grant No.42205080)the Natural Science Foundation of Sichuan(Grant No.2023YFS0442)the Research Fund of Civil Aviation Flight University of China(Grant No.J2022-037)supported by the National Key Scientific and Technological Infrastructure project“Earth System Science Numerical Simulator Facility”(Earth Lab)。
文摘The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus clouds.Accurately obtaining the entrainment rate(λ)is particularly important for its parameterization within the overall cumulus parameterization scheme.In this study,an improved bulk-plume method is proposed by solving the equations of two conserved variables simultaneously to calculateλof cumulus clouds in a large-eddy simulation.The results demonstrate that the improved bulk-plume method is more reliable than the traditional bulk-plume method,becauseλ,as calculated from the improved method,falls within the range ofλvalues obtained from the traditional method using different conserved variables.The probability density functions ofλfor all data,different times,and different heights can be well-fitted by a log-normal distribution,which supports the assumed stochastic entrainment process in previous studies.Further analysis demonstrate that the relationship betweenλand the vertical velocity is better than other thermodynamic/dynamical properties;thus,the vertical velocity is recommended as the primary influencing factor for the parameterization ofλin the future.The results of this study enhance the theoretical understanding ofλand its influencing factors and shed new light on the development ofλparameterization.
基金supported by the Youth Development Project of Air Force Military Medical University,No.21 QNPY072Key Project of Shaanxi Provincial Natural Science Basic Research Program,No.2023-JC-ZD-48(both to FF)。
文摘Elevated intraocular pressure(IOP)is one of the causes of retinal ischemia/reperfusion injury,which results in NRP3 inflammasome activation and leads to visual damage.Homerla is repo rted to play a protective role in neuroinflammation in the cerebrum.However,the effects of Homerla on NLRP3inflammasomes in retinal ischemia/reperfusion injury caused by elevated IOP remain unknown.In our study,animal models we re constructed using C57BL/6J and Homer1^(flox/-)/Homerla^(+/-)/Nestin-Cre^(+/-)mice with elevated IOP-induced retinal ischemia/repe rfusion injury.For in vitro expe riments,the oxygen-glucose deprivation/repe rfusion injury model was constructed with M uller cells.We found that Homerla ove rexpression amelio rated the decreases in retinal thickness and Muller cell viability after ischemia/reperfusion injury.Furthermore,Homerla knockdown promoted NF-κB P65^(Ser536)activation via caspase-8,NF-κB P65 nuclear translocation,NLRP3 inflammasome formation,and the production and processing of interleukin-1βand inte rleukin-18.The opposite results we re observed with Homerla ove rexpression.Finally,the combined administration of Homerla protein and JSH-23 significantly inhibited the reduction in retinal thickness in Homer1^(flox/-)Homer1a^(+/-)/Nestin-Cre^(+/-)mice and apoptosis in M uller cells after ischemia/reperfusion injury.Taken together,these studies demonstrate that Homer1a exerts protective effects on retinal tissue and M uller cells via the caspase-8/NF-KB P65/NLRP3 pathway after I/R injury.
文摘Objective: Digital healthcare is rapidly becoming a new model for medical development in the information society with its convenience, and personalization, and a research boom in digital healthcare has formed at home and abroad in recent years. The purpose of this study is to conduct a bibliometric analysis of the field of digital healthcare and to understand the research background and development trend in this field. Methods: A visual analysis of authors, institutions, journals and keywords was conducted using CiteSpace 5.8R3 software. Results: A total of 1646 digital healthcare-related retrieved from WoS and PubMed studies. There was an overall upward trend in the number of digital healthcare publications, with the highest number of publications in 2021 (290). The author AZIZ SHEIKH is ranked first in the number of published articles (13), while King Saud University (23) is the research institution with the most articles. Keyword clustering showed that the first cluster was data security;the common high frequency keywords that appeared were systems (85), artificial intelligence (82), mobile health (70), internet (61), and technology (57). Digital healthcare, artificial intelligence, healthcare services, machine learning and deep learning are the hotspot of current research. Conclusion: This paper summarises the state of the art in digital healthcare research. Using statistical analysis and network visualisation, it highlights the background, trends and hot topics in digital healthcare research. The paper finds that there is significant potential for artificial intelligence to help bridge the digital divide and reduce health inequalities. To understand the current state, hot trends and future directions of digital healthcare research, this paper can serve as a reference. .
文摘Consumption of shellfish contaminated with algal toxins produced by marine dinoflagellates can lead to diarrhetic shellfish poisoning (DSP). It was therefore essential that there are analytical techniques to identify and quantify DSP toxins in shellfish. This new methodology could facilitate DSP monitoring and create a means of rapidly responding to incidents threatening public health. In the last years there were different analytical methods for DSP, such as mouse bioassay and LC-FLD. With the development of instrument, Liquid chromatography-mass spectrometry was substituted for other analytical methods with its good sensitivity and selectivity and without derivatization for the determination of DSP. In this report, a high performance liquid chromatogra-phytandem mass spectrometric(HPLC-MS/MS)method was developed for the simultaneous determination of okadaic acid (OA) and dinophysistoxins(DTX1) in Sinonovacula constricta. Optimization of pretreatment experiment was carried out to maximize recoveries and the effectiveness. The analytes were determined under multi-reactions monitoring (MRM) scan type with tandem mass analyzer using negative ion electrospray ionization (-ESI) mode .Finally, the detection and identification of OA and DTX-1 were based upon their retention times (RT) and the fragmentation patterns of their mass spectra. The method of LOQ for the two poisons was 0.02 mg·kg-1.The real sample test showed that this method could be used for sensitive, fast, and accurate determination of the two diarrheic shellfish poisons in shellfish.
基金supported by the National Natural Science Foundation of China,No.81600738the Youth Development Project of Air Force Medical University,No.21QNPY072(both to FF)。
文摘Retinal injury after blunt ocular trauma may directly affect prognosis and lead to vision loss.To investigate the pathological changes and molecular mechanisms involved in retinal injury after blunt ocular trauma,we established a weight drop injury model of blunt ocular trauma in male Beagle dogs.Hematoxylin-eosin staining,immunofluorescence staining,western blotting,and TUNEL assays were performed to investigate retinal injury within 14 days after blunt ocular trauma.Compared with the control group,the thicknesses of the inner and outer nuclear layers,as well as the number of retinal ganglion cells,gradually decreased within 14 days after injury.The number of bipolar cells in the inner nuclear layer began to decrease 1 day after injury,while the numbers of cholinergic and amacrine cells in the inner nuclear layer did not decrease until 7 days after injury.Moreover,retinal cell necroptosis increased with time after injury;it progressed from the ganglion cell layer to the outer nuclear layer.Visual electrophysiological findings indicated that visual impairment began on the first day after injury and worsened over time.Additionally,blunt ocular trauma induced nerve regeneration and Müller glial hyperplasia;it also resulted in the recruitment of microglia to the retina and polarization of those microglia to the M1 phenotype.These findings suggest that necroptosis plays an important role in exacerbating retinal injury after blunt ocular trauma via gliosis and neuroinflammation.Such a role has important implications for the development of therapeutic strategies.
基金Supported by the National Key Research and Development Program of China(No.2019YFD0900704)the Yantai Key Research and Development Program(No.2019XDHZ097)+2 种基金the National Natural Science Foundation of China(No.42076137)the Natural Science Foundation of Shandong Province(No.ZR2020QD003)the Shandong Key Laboratory of Coastal Environmental Processes,YICCAS(No.2019SDHADKFJJ16)。
文摘We used the Integrated Biological Responses version 2(IBRv2)method to evaluate the biological eff ects of heavy metals in the sediments in Laizhou Bay,China on the benthic goby Acanthogobius ommaturus.In December 2018,gobies and sediments were collected from 15 stations.We measured the activities of defense enzymes and the contents of malondialdehyde(MDA)and metallothionein(MT)in the goby liver as well as the levels of heavy metals in the sediments and goby muscle tissue.Most of the heavy metal concentrations in sediment at each station were below the Class I criteria set by Chinese Standards for Marine Sediment Quality,and the Håkanson ecological risk index suggested low risk for the heavy metals.We found that A.ommaturus could eff ectively accumulate mercury,cadmium,arsenic,and zinc and that the contents of MT and MDA and the activities of glutathione peroxidase and glutathione reductase were suitable biomarkers of heavy metal pollution in this species.The IBRv2 method integrated these four biomarkers and discriminated stations according to heavy metal pollution.Higher IBRv2 values suggested more adverse eff ects in gobies,corroborating more serious heavy metal contamination.The stations with high IBRv2 values and high contents of heavy metals were mainly distributed in the west and northeast parts of the bay.These results show that the IBRv2 approach is a feasible strategy for assessing heavy metal pollution through biological response and biological status and that it can be implemented for environmental monitoring in Laizhou Bay.
基金financially supported by the Scientific and Technological Plan Projects of Guangzhou City(202103040001)。
文摘This work develops 2-Phenyl-1H-imidazole-1-sulfonate(PHIS)as a multi-functional electrolyte additive for H2O/HF scavenging and film formation to improve the high temperature performance of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)/graphite batteries.After 450 cycles at room temperature(25℃),the discharge capacity retentions of batteries with blank and PHIS-containing electrolyte are 56.03%and 94.92%respectively.After 230 cycles at high temperatures(45℃),their values are 75.30%and 88.38%respectively.The enhanced electrochemical performance of the batteries with PHIS-containing electrolyte is supported by the spectroscopic characterization and theoretical calculations.It is demonstrated that this PHIS electrolyte additive can facilitate the construction of the electrode interface films,remove the H2O/HF in the electrolyte,and improve the electrochemical performance of the batteries.This work not only develops a sulfonate-based electrolyte but also can stimulate new ideas of functional additives to improve the battery performance.
基金supported by the Natural Science Foundation of Shandong Province (ZR2020QH294 and ZR2021QH342)。
文摘The aim of this study was to investigate whether punicalagin(PU)could prevent obesity-related cardiac dysfunction by promoting DNA demethy lation,and to explore its possible mechanism.C57BL/6J mice were fed with standard diet,high-fat diet(HFD),HFD supplemented with resveratrol,low-dose PU(LPU)and high-dose PU(HPU)for 8 weeks.Compared with HFD group,body weight was significantly lower in PU treatment groups,number of cardionwocytes and the protein level of myosin heavy chain 7B were significantly higher in PU treatment groups.Levels of 5-hydroxymethylcytosine and 5-formylcytosine were significantly lower in HFD group than in other groups.Compared with the HFD group,the protein level of ten-eleven translocation enzyme(TET)2 was significantly higher in PU treatment groups,p-AMP-activated protein kinase(AMPK)was significantly higher in LPU group.Levels of total antioxidant capacity and the protein levels of complexesⅡ/Ⅲ/Ⅴ,oxoglutarate dehydrogenase,succinate dehydrogenase B and fumarate hdrolase were significantly lower in HFD group than PU treatment group.The ratio of(succinic acid+fumaric acid)/a-ketoglutarate was significantly higher in HFD group than other groups.In conclusion,PU up-regulated TETs enzyme activities and TET2 protein stability through alleviating mitochondrial dysfunction and activating AMPK,so as to promote DNA demethylation,thus preventing obesity-related cardiac dysfunction.
基金supported by the Science and Technology Project of State Grid Corporation of China(No.5400202133157A-0-0-00)partially supported by the State Grid Gansu Electric Power Company,China。
文摘Plasma nitrogen fixation(PNF)has been emerging as a promising technology for greenhouse gasfree and renewable energy-based agriculture.Yet,most PNF studies seldom address practical application-specific issues.In this work,we present the development of a compact and automatic PNF system for on-site agricultural applications.The system utilized a gliding-arc discharge as the plasma source and employed a dual-loop design to generate NO_(x)from air and water under atmospheric conditions.Experimental results showed that the system with a dualloop design performs well in terms of energy costs and production rates.Optimal operational parameters for the system were determined through experimentation,resulting in an energy cost of 13.9 MJ mol^(-1)and an energy efficiency of 16 g kWh^(-1)for NO_(3)^(-)production,respectively.Moreover,the concentration of exhausted NO_(x)was below the emission standards.Soilless lettuce cultivation experiments demonstrated that NO_(x)^(-)produced by the PNF system could serve as liquid nitrate nitrogen fertilizer.Overall,our work demonstrates the potential of the developed PNF system for on-site application in the production of green-leaf vegetables.
文摘BACKGROUND Oral implant surgery is an effective procedure for artificial implants in missing tooth areas under local anesthesia.Because patients under local anesthesia are conscious during this procedure,compared with general anesthesia-related operations,they are more likely to experience negative emotions,such as anxiety and tension.These emotional reactions result in shivering and chills in the limbs,leading to poor doctor-patient cooperation and even avoidance of treatment.In traditional Chinese medicine,it is believed that acupoint massage regulates blood and Qi,dredge menstruation,and relieve pain,which is beneficial for patients’emotional adjustment;however,there are few related clinical studies.AIM To observe the changes in anxiety and pain in patients with oral implant after acupoint massage combined with touch therapy.METHODS One hundred patients undergoing oral implantation in our hospital between May 2020 and May 2023 were randomly divided into control and study groups,according to a random number table,with 50 patients in each group.The control group received routine intervention,and the study group received acupoint massage combined with touch on the basis of the control group.Anxiety[assessed using the Modified Dental Anxiety Scale(MDAS)],pain severity,blood pressure,heart rate,and satisfaction were compared between the two groups.RESULTS Before intervention,the difference in MDAS score between the two groups was not significant(P>0.05),while after the intervention,the MDAS scores decreased in both groups compared with those before the intervention(P<0.05);the MDAS score of the study group was lower than that of the control group,with a statistically significant difference(P<0.05).The degree of pain in the intervention group was significantly lower than that in the control group(P<0.05).Before the intervention,there were no significant differences in systolic and diastolic blood pressures or heart rate between the two groups(P>0.05).The systolic and diastolic blood pressures and heart rate in the intervention group,during and after the intervention,were significantly lower than those in the control group(P<0.05).The total degree of satisfaction in the study group was significantly higher than that in the control group(P<0.05).CONCLUSION Acupoint massage combined with touch better relieves anxiety and pain in patients undergoing dental implant surgery,improving the perioperative comfort of these patients and ensuring safety and a smooth operation.
基金Supported by the Special Project of Technological Innovation of Hainan Provincial Research Institute(SQKY2022-0006)&Natural Science Foundation of Hainan Province(321MS0809).
文摘[Objectives]To study the anti-inflammatory effect of Elephantopus scaber L.extract on acute pleurisy induced by carrageenan in rats,and to explore its anti-inflammatory mechanism.[Methods]The active sites of E.scaber L.were extracted by ethanol reflux method.The extracts of different concentrations of E.scaber L.were used as the study object,and dexamethasone was used as the positive control drug.The anti-inflammatory effects of E.scaber L.extracts were studied by measuring the levels of malondialdehyde(MDA),prostaglandin E_(2)(PGE_(2)),tumor necrosis factor(TNF-α),interleukin-1β(IL-1β)in pleural fluid and serum nitric oxide(NO),MDA,PEG_(2),TNF-α,IL-1βin rats with acute pleurisy induced by carrageenan.[Results]E.scaber L.extracts in three doses could reduce the levels of inflammatory factors in pleural fluid and serum,and inhibit acute pleurisy in rats.It was speculated that the anti-inflammatory mechanism was related to the inhibition of the release of inflammatory factors and the antioxidant effect of extracts of three doses of E.scaber L.[Conclusions]This experiment provides a basis for the development and application of E.scaber L.
基金Supported by the National Outstanding Young Scientist Award of China, No. 30025016State Key Project for Basic Research, No. G1998051206Foundation of Henan Education Committee 1999125 the US NIH Grant, No. CA65871
文摘AIM: To characterize the histochemical type and pattern of intestinal metaplasia (IM) adjacent to gastric cardia adenocarcinoma (GCA) and distal gastric cancer (GC) in Linzhou, Henan Province, China.METHODS: Alcian-blue-periodic acid Schiff and high iron diamine-Alcian blue histochemical methods were performed on 142 cases of IM, including 49 cases of GCA and 93 cases of GC. All the patients were from Linzhou, Henan Province, China, the highest incidence area for both GCA and squamous cell carcinoma. Radio- or chemotherapy was not applied to these patients before surgery.RESULTS: The detection rate of IM in tissues adjacent to GCA tissues was 44.9%, which was significantly lower than that in GC tissues (80.64%, P<0.01). The rates of both incomplete small intestinal and colonic IM types identified by histochemistry in GCA tissues (31.82% and 63.64%, respectively) were significantly higher than those in GC (5.33% and 21.33%, respectively, P<0.01).CONCLUSION: IM in GCA and GC should be considered as a separate entity. Further research is needed to evaluate whether neoplastic progression of IM is related to its mucin profile in GCA.
基金This work was partly supported by the National Science Fund for Distinguished Young Scholars,grant number 41925016the National Natural Science Foundation of China,grant number 41804008.
文摘Synthetic Aperture Radar(SAR)interferometry is one of the most powerful remote sensing tools for ground deformation detection.However,tropospheric delay greatly limits the measurement accuracy of the InSAR technique.While vertically stratified tropospheric delays have been extensively investigated and well tackled,turbulent tropospheric phase noise still remains an intractable issue.In recent years,great efforts have been made to reduce the influence of turbulent atmospheric delay.This contribution is intended to provide a systematic review of the progress achieved in this field.First,it introduces the physical characteristics of atmospheric signals in interferograms.Then,a review of the main mitigation algorithms proposed in the literature is provided.In addition,the strengths and weaknesses of each approach are analyzed to provide guidance for choosing a suitable method accordingly.Finally,sug-gestions for resolving the challenging issues and an outlook for future research are given.
基金the National Natural Science Foundation of China(81472961)the Natural Science Foundation of Zhejiang Province(LY13H150001)the Zhejiang Provincial Program for the Cultivation of High-level Innovative Health Talents.
文摘BACKGROUND:This study aims to explore the characteristics of the epithelial-to-mesenchymal transition(EMT)process and its underlying molecular mechanisms in the period of paraquat(PQ)-induced pulmonary fi brosis(PF).METHODS:Picrosirius red staining and collagen volume fraction were utilized to evaluate the pathological changes of PQ-induced PF in rats.Immunohistochemistry,Western blot,and real-time reverse transcriptase-polymerase chain reaction(RT-PCR)were used to measure the protein and gene expression of EMT markers,EMT-associated transcription factors,and regulators of EMT-related pathways,respectively.RESULTS:The collagen deposition in the alveolar septum and increased PF markers were characteristics of pathological changes in PQ-induced PF,reached a peak on day 14 after PQ poisoning,and then decreased on day 21.The protein and gene expression of the fibrosis marker,EMT markers,transcription factors,and regulators of EMT-related signaling pathways signifi cantly increased at diff erent time points after PQ poisoning compared with corresponding controls(P<0.05),and most of them reached a peak on day 14,followed by a decrease on day 21.The gene expression of EMT markers was significantly correlated with PF markers,transcription factors,and regulators of EMT-related signaling pathways(P<0.05).The mRNA expression of transcription factors was signifi cantly correlated with that of TGF-β1 and Smad2(P<0.05 or P<0.01),instead of Wnt2 andβ-catenin(P>0.05).CONCLUSIONS:EMT process plays a role in the PQ-induced PF,in which most PF and EMT markers have a peak phenomenon,and its underlying molecular mechanisms might be determined by further studies.
文摘Paeoniflorin (PF) is one of the main bioactive components of total glucosides of paeony (TGP) extracted from the root of Paeonia lactiflora Pall. TGP exhibit various biological activities such as improvement in memory, hepatoprotection, antimutagenic properties and platelet aggregation inhibition. The aim of this paper is to review the pharmacokinetics (PK) of PF as a pure compound and in single or multiple herb(s) of traditional Chinese medicine (TCM) prescriptions. The distribution of PF or PF in TCM fitted one or two compartmental model after oral administration or intravenous injection, respectively. However, PF has a low bioavailability (BA) in rabbit (7.24%) and rat (3.24%) after oral administration. The PK profiles and BA of PF were remarkably improved when co-administered with sinomenine or glycyrrhizin acid. The PK profiles and BA of PF in Radix Paeonia Rubra (RP-R) and Jing-zhi guan-xin were improved, but in co-administration of RP-R with Radix Angelicae Sinensis, the BA was significantly reduced. PK profiles and BA of PF in Shan yao gan-cao tang or Danggui-Shaoyao-San was either remarkably improved or not. However, neither the PK profiles nor the BA of PF in Radix paeonia alba, Huangqin-tang Si ni san or Tang-Min-Ling-Wan was improved. Metabolism in the liver did not play any role in the low oral BA of PF. The low BA was thus attributed to poor permeation due to low lipophilicity, P-glycoprotein mediated efflux, intestinal bacteria and hydrolytic degradation in the intestine by the intestinal brush border lactase phlorizin hydrolase (LPH) and certain esterases. These findings show the in vivo course of PF and provide information on the maximum biological actions of PF that may help traditional Chinese herbal medicinal practitioners.
基金the National Natural Science Foundation of China(82020108019,82130070,81730065,82002347,81972032,and 81902202)The Medical Research Council(UK)MR/T016744/1 and MR/P010709/1the Versus Arthritis Senior Research Fellowship Award 20875.
文摘The circadian clock participates in maintaining homeostasis in peripheral tissues,including intervertebral discs(IVDs).Abnormal mechanical loading is a known risk factor for intervertebral disc degeneration(IDD).Based on the rhythmic daily loading pattern of rest and activity,we hypothesized that abnormal mechanical loading could dampen the IVD clock,contributing to IDD.Here,we investigated the effects of abnormal loading on the IVD clock and aimed to inhibit compression-induced IDD by targeting the core clock molecule brain and muscle Arnt-like protein-1(BMAL1).In this study,we showed that BMAL1 KO mice exhibit radiographic features similar to those of human IDD and that BMAL1 expression was negatively correlated with IDD severity by systematic analysis based on 149 human IVD samples.The intrinsic circadian clock in the IVD was dampened by excessive loading,and BMAL1 overexpression by lentivirus attenuated compression-induced IDD.Inhibition of the RhoA/ROCK pathway by Y-27632 or melatonin attenuated the compression-induced decrease in BMAL1 expression.Finally,the two drugs partially restored BMAL1 expression and alleviated IDD in a diurnal compression model.Our results first show that excessive loading dampens the circadian clock of nucleus pulposus tissues via the RhoA/ROCK pathway,the inhibition of which potentially protects against compression-induced IDD by preserving BMAL1 expression.These findings underline the importance of the circadian clock for IVD homeostasis and provide a potentially effective therapeutic strategy for IDD.
基金supported by the Assistant Secretary for Energy Efficiency and Renewable Energy,Vehicle Technologies Office,under the Advanced Battery Materials Research(BMR)Program of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231support by the U.S.Department of Energy under Contract No.106298-001+2 种基金the funding from Polish Ministry of Science and Higher Education No.1670/MOB/V/2017/0funding support of SUSTechthe resources of the National Energy Research Scientific Computing Center(NERSC)that is supported by the Office of Science of the U.S.Department of Energy。
文摘The lithium-sulfur(Li-S)battery is one of the most promising substitutes for current energy storage systems because of its low cost,high theoretical capacity,and high energy density.However,the high solubility of intermediate products(i.e.,lithium polysulfides)and the resultant shuttle effect lead to rapidly fading capacity and a low coulombic efficiency,which hinder the practical application of Li-S batteries.In this study,block copolymers are constructed with both an ethylene oxide unit and a styrene unit and then used as binders for Li-S batteries.Electrochemical performance improvements are attributed to the synergistic effects contributed by the different units of the block copolymer.The ethylene oxide unit traps polysulfide,which bonds strongly with the intermediate lithium polysulfide,and enhances the transport of lithium ions to reach high capacity.Meanwhile,the styrene unit maintains cathode integrity by improving the mechanical properties and elasticity of the constructed block copolymer to accommodate the large volume changes.By enabling multiple functions via different units in the polymer chain,high sulfur utilization is achieved,polysulfide diffusion is confined,and the shuttle effect is suppressed during the cycle life of Li-S batteries,as revealed by operando ultraviolet-visible spectroscopy and S Kedge X-ray absorption spectroscopy.
基金supported by the National Natural Science Foundation of China (Grant No. 62004080)the Postdoctoral Innovative Talents Supporting Program (Grant No. BX20190143)the China Postdoctoral Science Foundation (Grant No. 2020M670834)。
文摘Two-dimensional(2D) layered perovskites have emerged as potential alternates to traditional three-dimensional(3D)analogs to solve the stability issue of perovskite solar cells. In recent years, many efforts have been spent on manipulating the interlayer organic spacing cation to improve the photovoltaic properties of Dion–Jacobson(DJ) perovskites. In this work, a serious of cycloalkane(CA) molecules were selected as the organic spacing cation in 2D DJ perovskites, which can widely manipulate the optoelectronic properties of the DJ perovskites. The underlying relationship between the CA interlayer molecules and the crystal structures, thermodynamic stabilities, and electronic properties of 58 DJ perovskites has been investigated by using automatic high-throughput workflow cooperated with density-functional(DFT) calculations.We found that these CA-based DJ perovskites are all thermodynamic stable. The sizes of the cycloalkane molecules can influence the degree of inorganic framework distortion and further tune the bandgaps with a wide range of 0.9–2.1 eV.These findings indicate the cycloalkane molecules are suitable as spacing cation in 2D DJ perovskites and provide a useful guidance in designing novel 2D DJ perovskites for optoelectronic applications.
