Non-Hermitian Hamiltonians are widely used in describing open systems with gain and loss,among which a key phenomenon is the non-Hermitian skin effect.Here we report an experimental scheme to realize a twodimensional(...Non-Hermitian Hamiltonians are widely used in describing open systems with gain and loss,among which a key phenomenon is the non-Hermitian skin effect.Here we report an experimental scheme to realize a twodimensional(2D)discrete-time quantum walk with non-Hermitian skin effect in a single trapped ion.It is shown that the coin and 2D walker states can be labeled in the spin of the ion and the coherent-state lattice of the ion motion,respectively.We numerically observe a directional bulk flow,whose orientations are controlled by dissipative parameters,showing the emergence of the non-Hermitian skin effect.We then discuss an experimental implementation of our scheme in a laser-controlled trapped Ca^(+)ion.Our experimental proposal may be applicable to research of dissipative quantum walk systems and may be able to generalize to other platforms,such as superconducting circuits and atoms in cavity.展开更多
BACKGROUND：As the regulators of cytokines, suppressors of cytokine signaling （SOCS） play an important role in the inflammation reaction. Some studies found that SOCS-1 and SOCS-3 were involved in the pathogenesis o...BACKGROUND：As the regulators of cytokines, suppressors of cytokine signaling （SOCS） play an important role in the inflammation reaction. Some studies found that SOCS-1 and SOCS-3 were involved in the pathogenesis of some inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease. But the expressions of SOCS in coronary heart disease have not yet been reported. This study aimed to investigate the expression and clinical significance of SOCS-1 and SOCS-3 in the myocardium of patients with sudden cardiac death （SCD）.METHODS： Myocardial autopsy specimens were collected from 24 patients at the Forensic Medicine Department of Sun Yat-Sen University, Guangzhou, China between 2005 and 2006. Of them, 9 patients had autopsy findings consistent with coronary atherosclerosis （non-myocardial infarction） leading to SCD （non-MI group）, 7 died of acute myocardial infaction （MI group）, and 8 died from traffic accidents and trauma （control group）. The expressions of SOCS-1 mRNA and SOCS-3 mRNA in the myocardium of the non-MI, MI and control groups were detected using RT-PCR. The levels of SOCS-1 and SOCS-3 proteins were detected using immunohistochemistry. Statistical analyses were performed using SPSS version 13.0 sottware and the data were analyzed by ANOVA.RESULTS： The expressions of SOCS-1 mRNA and SOCS-3 mRNA in the non-MI and MI groups were significantly higher than those in the control group[（0.788±0.101）, （0.741±0.111） vs. （0.436±0.044）, （P〈0.01）; （0.841±0.092）, （0.776±0.070） vs. （0.454±0.076）, （P〈0.01）] respectively. The antibody-positive cells of SOCS-1 protein in the myocardium of the non-MI and MI groups were significantly higher than those in the myocardium of the control group[（320.00±48.48）, （347.14±70.88） vs. （42.50±10.35）, （P〈0.01）] respectively. The antibody-positive cells of SOCS-3 protein in the myocardium of the non-MI and MI groups were significantly higher than those in the myocardium of the control group[（381.11 ±59.25） vs. （40.00±10.69）, （P〈0.01）] and[（332.86±111.91） vs. （40.00±10.69）, （P=0.001）].CONCLUSION： The expressions of SOCS-1 and SOCS-3 in the myocardium of patients with SCD from coronary heart disease are significantly increased and contribute to the pathogenesis of SCD.展开更多
表面辅助的金属有机纳米结构因其结构稳定性和潜在应用受到广泛关注。在金属有机纳米结构中,金属原子来源于外部沉积的金属或金属表面原子。外部沉积的金属原子种类多样,取决于目标纳米结构。然而,金属表面原子受限于表面科学常用的金...表面辅助的金属有机纳米结构因其结构稳定性和潜在应用受到广泛关注。在金属有机纳米结构中,金属原子来源于外部沉积的金属或金属表面原子。外部沉积的金属原子种类多样,取决于目标纳米结构。然而,金属表面原子受限于表面科学常用的金、银和铜单晶金属表面。金属有机纳米结构大多包括Au配位或是Cu配位结构,而只有少量的用表面Ag原子构成。分子金属相互作用的进一步研究有助于预期纳米结构的精确控制形成。至于构建基元,有机分子通过M―C、M―N和M―O键与表面金属原子配位。末端炔反应或者乌尔曼耦合能够实现C―M―C节点的形成。Cu和Au原子能够与含有末端氰基或吡啶基官能团的分子配位形成N―M―N键。另外,表面Ag增原子能够通过Ag―N配位键与酞菁分子配位。然而,M―O配位键的相关研究较少。因此,我们计划使用末端羟基分子与Ag增原子配位形成金属有机配位纳米结构去研究O―Ag节点。我们通过扫描隧道显微镜利用4,4’-二羟基-1,1’:3’,1’’-三联苯分子(4,4’-dihydroxy-1,1’:3’,1’’-terphenyl,H3PH)和Ag增原子成功构筑了一系列二维有序纳米结构。在室温下,蒸镀的H3PH分子自组装形成由环氢键连接的密堆积结构。当退火温度提升到330K,一种新的纳米结构出现了,该结构由O―Ag配位键和氢键共同作用形成。进一步地提升退火温度至420K,蜂巢结构和共存的二重配位链出现,这两种结构中仅由O―Ag―O键构成。为分析金属分子反应路径和O―Ag―O键的能量势垒,我们对该体系进行密度泛函理论计算。计算结果显示,O―Ag键形成的能量势垒是1.41 eV,小于O―Ag―O节点1.85 e V的能量势垒。这也解释了分等级金属-有机纳米结构形成的原因。我们的实验结果提供了一种利用有机小分子和金属增原子来设计和构筑分等级二维纳米结构的有效方法。展开更多
BACKGROUND:We aimed to investigate the gene expression of myocardial ischemia/reperfusion injury(MIRI)in patients with acute ST-elevation myocardial infarction(STEMI)using stress and toxicity pathway gene chip technol...BACKGROUND:We aimed to investigate the gene expression of myocardial ischemia/reperfusion injury(MIRI)in patients with acute ST-elevation myocardial infarction(STEMI)using stress and toxicity pathway gene chip technology and try to determine the underlying mechanism.METHODS:The mononuclear cells were separated by ficoll centrifugation,and plasma total antioxidant capacity(T-AOC)was determined by the ferric reducing ability of plasma(FRAP)assay.The expression of toxic oxidative stress genes was determined and verified by oligo gene chip and quantitative real-time polymerase chain reaction(qRT-PCR).Additionally,gene ontology(GO)enrichment analysis was performed on DAVID website to analyze the potential mechanism further.RESULTS:The total numbers of white blood cells(WBC)and neutrophils(N)in the peripheral blood of STEMI patients(the AMI group)were significantly higher than those in the control group(WBC:11.67±4.85×10^(9)/L vs.6.41±0.72×10^(9)/L,P<0.05;N:9.27±4.75×10^(9)/L vs.3.89±0.81×10^(9)/L,P<0.05),and WBCs were significantly associated with creatine kinase-myocardial band(CK-MB)on the first day(Y=8.945+0.018X,P<0.05).In addition,the T-AOC was significantly lower in the AMI group comparing to the control group(12.80±1.79 U/mL vs.20.48±2.55 U/mL,P<0.05).According to the gene analysis,eight up-regulated differentially expressed genes(DEGs)included GADD45A,PRDX2,HSPD1,DNAJB1,DNAJB2,RAD50,TNFSF6,and TRADD.Four down-regulated DEGs contained CCNG1,CAT,CYP1A1,and ATM.TNFSF6 and CYP1A1 were detected by polymerase chain reaction(PCR)to verify the expression at different time points,and the results showed that TNFSF6 was up-regulated and CYP1A1 was down-regulated as the total expression.GO and kyoto encyclopedia of genes and genomes(KEGG)enrichment analysis suggested that the oxidative stress genes mediate MIRI via various ways such as unfolded protein response(UPR)and apoptosis.CONCLUSIONS:WBCs,especially neutrophils,were the critical cells that mediating reperfusion injury.MIRI was regulated by various genes,including oxidative metabolic stress,heat shock,DNA damage and repair,and apoptosis-related genes.The underlying pathway may be associated with UPR and apoptosis,which may be the novel therapeutic target.展开更多
Background:Since the trauma knowledge of trauma providers correlates with the outcomes of injured patients,this study aims to assess the socio-demographic characteristics and levels of trauma knowledge of trainees in ...Background:Since the trauma knowledge of trauma providers correlates with the outcomes of injured patients,this study aims to assess the socio-demographic characteristics and levels of trauma knowledge of trainees in the China trauma care training(CTCT)program in addition to their post-course test results to provide support for the development of trauma care training programs and trauma systems in China.Methods:A cross-sectional study was conducted by collecting demographic information,hospital-related information and trauma knowledge of the trainees from 19 regions in China.All participants were assessed by questionnaires collecting the socio-demographic data,the trauma care knowledge levels and the information of the hospitals.Results:There were 955 males(78.9%)and 256 females(21.1%)enrolled.Among them,854 were physicians(70.5%),357 were registered nurses(29.5%).In addition,64 of them also played an administrative role in the hospitals(5.3%).The score of the trainees who were members of the emergency department staff(72.59±14.13)was the highest among the scores of all the personnel surveyed,followed by those of the trainees from the intensive care unit(ICU)(71.17±12.72),trauma surgery department(67.26±13.81),orthopedics department(70.36±14.48),general surgery department(69.91±14.79)and other departments(69.93±16.91),P=0.031.The score of the professors(73.09±15.05)was higher than those of the associate professors(72.40±14.71),lecturers(70.07±14.25)and teaching assistants(67.58±15.16),P<0.0001.The score of the individuals who attended experts’trauma lectures(72.22±14.45)was higher than that of individuals who did not attend the lectures(69.33±15.17),P=0.001.The mean scores before and after the training were 71.02±14.82 and 84.24±13.77,respectively,P<0.001.The mean score of trauma knowledge after the training of trainees from different provinces and with different educational backgrounds was higher than that before the training,with a statistically significant difference(P<0.05).Conclusions:The level of trauma knowledge of trauma care providers was associated with their department,professional position and previous participation in related academic conferences.Trauma care experience and participation in academic lectures and training program including CTCT may effectively improve individuals’level of trauma knowledge.展开更多
Due to the development of the novel materials,the past two decades have witnessed the rapid advances of soft electronics.The soft electronics have huge potential in the physical sign monitoring and health care.One of ...Due to the development of the novel materials,the past two decades have witnessed the rapid advances of soft electronics.The soft electronics have huge potential in the physical sign monitoring and health care.One of the important advantages of soft electronics is forming good interface with skin,which can increase the user scale and improve the signal quality.Therefore,it is easy to build the specific dataset,which is important to improve the performance of machine learning algorithm.At the same time,with the assistance of machine learning algorithm,the soft electronics have become more and more intelligent to realize real-time analysis and diagnosis.The soft electronics and machining learning algorithms complement each other very well.It is indubitable that the soft electronics will bring us to a healthier and more intelligent world in the near future.Therefore,in this review,we will give a careful introduction about the new soft material,physiological signal detected by soft devices,and the soft devices assisted by machine learning algorithm.Some soft materials will be discussed such as two-dimensional material,carbon nanotube,nanowire,nanomesh,and hydrogel.Then,soft sensors will be discussed according to the physiological signal types(pulse,respiration,human motion,intraocular pressure,phonation,etc.).After that,the soft electronics assisted by various algorithms will be reviewed,including some classical algorithms and powerful neural network algorithms.Especially,the soft device assisted by neural network will be introduced carefully.Finally,the outlook,challenge,and conclusion of soft system powered by machine learning algorithm will be discussed.展开更多
Background:Intra-abdominal hypertension(IAH) is a disease with high morbidity and mortality among critically ill patients.The study's objectives were to explore the prevalence of IAH and physicians' awareness ...Background:Intra-abdominal hypertension(IAH) is a disease with high morbidity and mortality among critically ill patients.The study's objectives were to explore the prevalence of IAH and physicians' awareness of the 2013 World Society of Abdominal Compartment Syndrome(WSACS) guidelines in Chinese intensive care units(ICUs).Methods:A cross-sectional study of four ICUs in Southwestern China was conducted from June 17 to August 2,2014.Adult patients admitted to the ICU for more than 24 h,with bladder catheter but without obvious intravesical pressure(IVP) measurement contraindications,were recruited.Intensivists with more than 5 years of ICU working experience were also recruited.Epidemiological information,potential IAH risk factors,IVP measurements and questionnaire results were recorded.Results:Forty-one patients were selected.Fifteen(36.59%) had IVP?12mm Hg.SOFA(Sequential Organ Failure Assessment) hepatic and neurological sub-scores were utilized as independent predictors for IAH via logistic backward analysis.Thirty-seven intensivists participated in the survey(response rate:80.43%).The average score of each center was less than 35 points.All physicians believed the IAH prevalence in their departments was no more than 20.00%.A significant negative correlation was observed between the intensivists' awareness of the 2013 WSACS guidelines and the IAH prevalence in each center(r=-0.975,P=0.025).Conclusion:The prevalence and independent predictors of IAH among the surveyed population are similar to the reports in the literature.Intensivists generally have a low awareness of the 2013 WSACS guidelines.A systematic guideline training program is vital for improving the efficiency of the diagnosis and treatment of IAH.展开更多
In high intensity focused ultrasound(HIFU)treatment,it is crucial to accurately identify denatured and normal biological tissues.In this paper,a novel method based on compressed sensing(CS)and refined composite multi-...In high intensity focused ultrasound(HIFU)treatment,it is crucial to accurately identify denatured and normal biological tissues.In this paper,a novel method based on compressed sensing(CS)and refined composite multi-scale fuzzy entropy(RCMFE)is proposed.First,CS is used to denoise the HIFU echo signals.Then the multi-scale fuzzy entropy(MFE)and RCMFE of the denoised HIFU echo signals are calculated.This study analyzed 90 cases of HIFU echo signals,including 45 cases in normal status and 45 cases in denatured status,and the results show that although both MFE and RCMFE can be used to identify denatured tissues,the intra-class distance of RCMFE on each scale factor is smaller than MFE,and the inter-class distance is larger than MFE.Compared with MFE,RCMFE can calculate the complexity of the signal more accurately and improve the stability,compactness,and separability.When RCMFE is selected as the characteristic parameter,the RCMFE difference between denatured and normal biological tissues is more evident than that of MFE,which helps doctors evaluate the treatment effect more accurately.When the scale factor is selected as 16,the best distinguishing effect can be obtained.展开更多
With the vigorous development of automobile industry,in-vehicle network is also constantly upgraded to meet data transmission requirements of emerging applications.The main transmission requirements are low latency an...With the vigorous development of automobile industry,in-vehicle network is also constantly upgraded to meet data transmission requirements of emerging applications.The main transmission requirements are low latency and certainty especially for autonomous driving.Time sensitive networking(TSN)based on Ethernet gives a possible solution to these requirements.Previous surveys usually investigated TSN from a general perspective,which referred to TSN of various application fields.In this paper,we focus on the application of TSN to the in-vehicle networks.For in-vehicle networks,we discuss all related TSN standards specified by IEEE 802.1 work group up to now.We further overview and analyze recent literature on various aspects of TSN for automotive applications,including synchronization,resource reservation,scheduling,certainty,software and hardware.Application scenarios of TSN for in-vehicle networks are analyzed one by one.Since TSN of in-vehicle network is still at a very initial stage,this paper also gives insights on open issues,future research directions and possible solutions.展开更多
A porous 3D cross-linked conductive network pierced by multi-wall carbon nanotubes(MWCNTs) was successfully designed from zeolitic imidazolate framework-8(ZIF-8). Zn@NPC@MWCNTs composites were tailored by the facile r...A porous 3D cross-linked conductive network pierced by multi-wall carbon nanotubes(MWCNTs) was successfully designed from zeolitic imidazolate framework-8(ZIF-8). Zn@NPC@MWCNTs composites were tailored by the facile regulating the mass ratios and thermal annealing treatment. Due to the combination of less eddy current loss and dielectric loss together with multiple reflection attenuation caused by a unique structure. With a 10 wt% filler loading, the Zn@NPC@MWCNTs composites carbonized at 800℃ show two high reflection loss(RL) values with different thicknesses. An RL value is-53.18 dB with 4.09 mm thickness in the C-Band(4-8 GHz), and a minimum RL can reach-74.83 d B(10.8 GHz)with a matching thickness of 2.749 mm. The effective absorption bandwidth is 4 GHz(from 8 to 12 GHz,RL ≤-10 d B), which just covers the full X-band. Low cost and easy preparation can also provide advantages to develop MOF-based materials as effective EMW absorbents.展开更多
A new route was developed for the synthesis of renewable decalin with cyclopentanone which can be derived from lignocellulose.It was found that 1,2,3,4,5,6,7,8-octahydronaphthalene could be selectively produced by the...A new route was developed for the synthesis of renewable decalin with cyclopentanone which can be derived from lignocellulose.It was found that 1,2,3,4,5,6,7,8-octahydronaphthalene could be selectively produced by the hydrogenation/dehydration/rearrangement of [1,1-bi(cyclopentylidene)]-2-one(i.e.the selfaldol condensation product of cyclopentanone) over a dual-bed catalyst system.Among the investigated catalysts,the Ru/C and Amberlyst-15 resin exhibited the highest activities for the hydrogenation of [1,1-bi(cyclopentylidene)]-2-one to [1,1-bi(cyclopentan)]-2-ol and the dehydration/rearrangement of [1,1-bi(cyclopentan)]-2-ol to 1,2,3,4,5,6,7,8-octahydronaphthalene,respectively.Using Ru/C and Amberlyst-15 resin as the first bed and the second bed catalysts,1,2,3,4,5,6,7,8-octahydronaphthalene was directly produced in high carbon yield(83.7%) under mild conditions(393 K,1 MPa).After being hydrogenated,the1,2,3,4,5,6,7,8-octahydronaphthalene was converted to decalin which can be used as additive to improve the thermal stability and volumetric heat value of jet fuel.展开更多
By throwing a particle with electric charge and angular momentum into the black holes, much evidence shows that the naked singularity of some （3＋1）-dimensional black holes might be seen, which is not allowed in the...By throwing a particle with electric charge and angular momentum into the black holes, much evidence shows that the naked singularity of some （3＋1）-dimensional black holes might be seen, which is not allowed in the weak cosmic censorship conjecture. In this study, we consider a （2＋1）-dimensional Peldan black hole and find that it could be destroyed under certain conditions in both extreme and near-extreme cases.展开更多
The transmission medium of natural gas gathering and transportation pipelines usually contains cor-rosive gases,which will cause serious corrosion on the inner wall of the pipelines when they coexist with water.Theref...The transmission medium of natural gas gathering and transportation pipelines usually contains cor-rosive gases,which will cause serious corrosion on the inner wall of the pipelines when they coexist with water.Therefore,it is necessary to add corrosion inhibitor to form a protective film to protect the pipeline.The distribution of corrosion inhibitors in a gathering and transportation pipeline in Moxi gas field was studied by combining experiment and simulation.The Pearson function was used to calculate the experimental and simulation results,and the correlation was more than 80%,indicating a high degree of agreement.The simulation results show that:①The larger the pipe angle,filling speed and gas flow rate,the smaller the particle size,the better the distribution of corrosion inhibitor particles in the pipe.The filling amount will affect the concentration,but the distribution trend is unchanged;②A method to determine the filling mode based on the loss was proposed,and for this pipeline,the loss of corrosion inhibitor was determined to be 5.31×10^(-3) kg/s,and the flling amount was recommended to be adjusted to 2o L/h,which has certain guiding significance for the actual flling strategy of pipeline corrosion inhibitor.展开更多
In the study of weak cosmic censorship conjectures(WCCC),some research finds that the Reissner-Nordström black hole might be destroyed by a test particle with particular mass and charge under some conditions,whic...In the study of weak cosmic censorship conjectures(WCCC),some research finds that the Reissner-Nordström black hole might be destroyed by a test particle with particular mass and charge under some conditions,which means that the naked singularity of the black hole could be observed.This is not allowed in WCCC.We have never observed such naked singularities which should not exist in theory,so we need to find a proper way to protect the black hole from being destroyed by such particles.In this paper,we study a Reissner-Nordström black hole that is surrounded by quintessence(RN-Q)and find that the black hole would be stable and safe because of the effective potential barrier induced by the quintessence term.This result may also show in a sense that the quintessence might have more potential value.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.92165206 and 11974330)the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0301603)the Fundamental Research Funds for the Central Universities。
文摘Non-Hermitian Hamiltonians are widely used in describing open systems with gain and loss,among which a key phenomenon is the non-Hermitian skin effect.Here we report an experimental scheme to realize a twodimensional(2D)discrete-time quantum walk with non-Hermitian skin effect in a single trapped ion.It is shown that the coin and 2D walker states can be labeled in the spin of the ion and the coherent-state lattice of the ion motion,respectively.We numerically observe a directional bulk flow,whose orientations are controlled by dissipative parameters,showing the emergence of the non-Hermitian skin effect.We then discuss an experimental implementation of our scheme in a laser-controlled trapped Ca^(+)ion.Our experimental proposal may be applicable to research of dissipative quantum walk systems and may be able to generalize to other platforms,such as superconducting circuits and atoms in cavity.
文摘BACKGROUND：As the regulators of cytokines, suppressors of cytokine signaling （SOCS） play an important role in the inflammation reaction. Some studies found that SOCS-1 and SOCS-3 were involved in the pathogenesis of some inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease. But the expressions of SOCS in coronary heart disease have not yet been reported. This study aimed to investigate the expression and clinical significance of SOCS-1 and SOCS-3 in the myocardium of patients with sudden cardiac death （SCD）.METHODS： Myocardial autopsy specimens were collected from 24 patients at the Forensic Medicine Department of Sun Yat-Sen University, Guangzhou, China between 2005 and 2006. Of them, 9 patients had autopsy findings consistent with coronary atherosclerosis （non-myocardial infarction） leading to SCD （non-MI group）, 7 died of acute myocardial infaction （MI group）, and 8 died from traffic accidents and trauma （control group）. The expressions of SOCS-1 mRNA and SOCS-3 mRNA in the myocardium of the non-MI, MI and control groups were detected using RT-PCR. The levels of SOCS-1 and SOCS-3 proteins were detected using immunohistochemistry. Statistical analyses were performed using SPSS version 13.0 sottware and the data were analyzed by ANOVA.RESULTS： The expressions of SOCS-1 mRNA and SOCS-3 mRNA in the non-MI and MI groups were significantly higher than those in the control group[（0.788±0.101）, （0.741±0.111） vs. （0.436±0.044）, （P〈0.01）; （0.841±0.092）, （0.776±0.070） vs. （0.454±0.076）, （P〈0.01）] respectively. The antibody-positive cells of SOCS-1 protein in the myocardium of the non-MI and MI groups were significantly higher than those in the myocardium of the control group[（320.00±48.48）, （347.14±70.88） vs. （42.50±10.35）, （P〈0.01）] respectively. The antibody-positive cells of SOCS-3 protein in the myocardium of the non-MI and MI groups were significantly higher than those in the myocardium of the control group[（381.11 ±59.25） vs. （40.00±10.69）, （P〈0.01）] and[（332.86±111.91） vs. （40.00±10.69）, （P=0.001）].CONCLUSION： The expressions of SOCS-1 and SOCS-3 in the myocardium of patients with SCD from coronary heart disease are significantly increased and contribute to the pathogenesis of SCD.
文摘表面辅助的金属有机纳米结构因其结构稳定性和潜在应用受到广泛关注。在金属有机纳米结构中,金属原子来源于外部沉积的金属或金属表面原子。外部沉积的金属原子种类多样,取决于目标纳米结构。然而,金属表面原子受限于表面科学常用的金、银和铜单晶金属表面。金属有机纳米结构大多包括Au配位或是Cu配位结构,而只有少量的用表面Ag原子构成。分子金属相互作用的进一步研究有助于预期纳米结构的精确控制形成。至于构建基元,有机分子通过M―C、M―N和M―O键与表面金属原子配位。末端炔反应或者乌尔曼耦合能够实现C―M―C节点的形成。Cu和Au原子能够与含有末端氰基或吡啶基官能团的分子配位形成N―M―N键。另外,表面Ag增原子能够通过Ag―N配位键与酞菁分子配位。然而,M―O配位键的相关研究较少。因此,我们计划使用末端羟基分子与Ag增原子配位形成金属有机配位纳米结构去研究O―Ag节点。我们通过扫描隧道显微镜利用4,4’-二羟基-1,1’:3’,1’’-三联苯分子(4,4’-dihydroxy-1,1’:3’,1’’-terphenyl,H3PH)和Ag增原子成功构筑了一系列二维有序纳米结构。在室温下,蒸镀的H3PH分子自组装形成由环氢键连接的密堆积结构。当退火温度提升到330K,一种新的纳米结构出现了,该结构由O―Ag配位键和氢键共同作用形成。进一步地提升退火温度至420K,蜂巢结构和共存的二重配位链出现,这两种结构中仅由O―Ag―O键构成。为分析金属分子反应路径和O―Ag―O键的能量势垒,我们对该体系进行密度泛函理论计算。计算结果显示,O―Ag键形成的能量势垒是1.41 eV,小于O―Ag―O节点1.85 e V的能量势垒。这也解释了分等级金属-有机纳米结构形成的原因。我们的实验结果提供了一种利用有机小分子和金属增原子来设计和构筑分等级二维纳米结构的有效方法。
基金National Natural Science Foundation of China(81670220,31270992,and 30800215)Guangdong Provincial Natural Science Foundation(2014A030313086)+2 种基金Guangdong Provincial Science and Technology Plan Project(2015A020212013)Guangzhou Science and Technology Project(201804010007)This research was approved by the Ethics Committee of the First Affiliated Hospital of Sun Yat-sen University([2019]176).
文摘BACKGROUND:We aimed to investigate the gene expression of myocardial ischemia/reperfusion injury(MIRI)in patients with acute ST-elevation myocardial infarction(STEMI)using stress and toxicity pathway gene chip technology and try to determine the underlying mechanism.METHODS:The mononuclear cells were separated by ficoll centrifugation,and plasma total antioxidant capacity(T-AOC)was determined by the ferric reducing ability of plasma(FRAP)assay.The expression of toxic oxidative stress genes was determined and verified by oligo gene chip and quantitative real-time polymerase chain reaction(qRT-PCR).Additionally,gene ontology(GO)enrichment analysis was performed on DAVID website to analyze the potential mechanism further.RESULTS:The total numbers of white blood cells(WBC)and neutrophils(N)in the peripheral blood of STEMI patients(the AMI group)were significantly higher than those in the control group(WBC:11.67±4.85×10^(9)/L vs.6.41±0.72×10^(9)/L,P<0.05;N:9.27±4.75×10^(9)/L vs.3.89±0.81×10^(9)/L,P<0.05),and WBCs were significantly associated with creatine kinase-myocardial band(CK-MB)on the first day(Y=8.945+0.018X,P<0.05).In addition,the T-AOC was significantly lower in the AMI group comparing to the control group(12.80±1.79 U/mL vs.20.48±2.55 U/mL,P<0.05).According to the gene analysis,eight up-regulated differentially expressed genes(DEGs)included GADD45A,PRDX2,HSPD1,DNAJB1,DNAJB2,RAD50,TNFSF6,and TRADD.Four down-regulated DEGs contained CCNG1,CAT,CYP1A1,and ATM.TNFSF6 and CYP1A1 were detected by polymerase chain reaction(PCR)to verify the expression at different time points,and the results showed that TNFSF6 was up-regulated and CYP1A1 was down-regulated as the total expression.GO and kyoto encyclopedia of genes and genomes(KEGG)enrichment analysis suggested that the oxidative stress genes mediate MIRI via various ways such as unfolded protein response(UPR)and apoptosis.CONCLUSIONS:WBCs,especially neutrophils,were the critical cells that mediating reperfusion injury.MIRI was regulated by various genes,including oxidative metabolic stress,heat shock,DNA damage and repair,and apoptosis-related genes.The underlying pathway may be associated with UPR and apoptosis,which may be the novel therapeutic target.
基金support by grants from the“Chongqing Science and Technology Benefiting project”(cstc2016kjhmpt1001)research project from the State Key Laboratory of Trauma,Burns and Combined Injury(SKLZZ201603)。
文摘Background:Since the trauma knowledge of trauma providers correlates with the outcomes of injured patients,this study aims to assess the socio-demographic characteristics and levels of trauma knowledge of trainees in the China trauma care training(CTCT)program in addition to their post-course test results to provide support for the development of trauma care training programs and trauma systems in China.Methods:A cross-sectional study was conducted by collecting demographic information,hospital-related information and trauma knowledge of the trainees from 19 regions in China.All participants were assessed by questionnaires collecting the socio-demographic data,the trauma care knowledge levels and the information of the hospitals.Results:There were 955 males(78.9%)and 256 females(21.1%)enrolled.Among them,854 were physicians(70.5%),357 were registered nurses(29.5%).In addition,64 of them also played an administrative role in the hospitals(5.3%).The score of the trainees who were members of the emergency department staff(72.59±14.13)was the highest among the scores of all the personnel surveyed,followed by those of the trainees from the intensive care unit(ICU)(71.17±12.72),trauma surgery department(67.26±13.81),orthopedics department(70.36±14.48),general surgery department(69.91±14.79)and other departments(69.93±16.91),P=0.031.The score of the professors(73.09±15.05)was higher than those of the associate professors(72.40±14.71),lecturers(70.07±14.25)and teaching assistants(67.58±15.16),P<0.0001.The score of the individuals who attended experts’trauma lectures(72.22±14.45)was higher than that of individuals who did not attend the lectures(69.33±15.17),P=0.001.The mean scores before and after the training were 71.02±14.82 and 84.24±13.77,respectively,P<0.001.The mean score of trauma knowledge after the training of trainees from different provinces and with different educational backgrounds was higher than that before the training,with a statistically significant difference(P<0.05).Conclusions:The level of trauma knowledge of trauma care providers was associated with their department,professional position and previous participation in related academic conferences.Trauma care experience and participation in academic lectures and training program including CTCT may effectively improve individuals’level of trauma knowledge.
基金supported by National Natural Science Foundation of China(No.62201624,32000939,21775168,22174167,51861145202,U20A20168)the Guangdong Basic and Applied Basic Research Foundation(2019A1515111183)+3 种基金Shenzhen Research Funding Program(JCYJ20190807160401657,JCYJ201908073000608,JCYJ20150831192224146)the National Key R&D Program(2018YFC2001202)the support of the Research Fund from Tsinghua University Initiative Scientific Research Programthe support from Key Laboratory of Sensing Technology and Biomedical Instruments of Guangdong Province(No.2020B1212060077)。
文摘Due to the development of the novel materials,the past two decades have witnessed the rapid advances of soft electronics.The soft electronics have huge potential in the physical sign monitoring and health care.One of the important advantages of soft electronics is forming good interface with skin,which can increase the user scale and improve the signal quality.Therefore,it is easy to build the specific dataset,which is important to improve the performance of machine learning algorithm.At the same time,with the assistance of machine learning algorithm,the soft electronics have become more and more intelligent to realize real-time analysis and diagnosis.The soft electronics and machining learning algorithms complement each other very well.It is indubitable that the soft electronics will bring us to a healthier and more intelligent world in the near future.Therefore,in this review,we will give a careful introduction about the new soft material,physiological signal detected by soft devices,and the soft devices assisted by machine learning algorithm.Some soft materials will be discussed such as two-dimensional material,carbon nanotube,nanowire,nanomesh,and hydrogel.Then,soft sensors will be discussed according to the physiological signal types(pulse,respiration,human motion,intraocular pressure,phonation,etc.).After that,the soft electronics assisted by various algorithms will be reviewed,including some classical algorithms and powerful neural network algorithms.Especially,the soft device assisted by neural network will be introduced carefully.Finally,the outlook,challenge,and conclusion of soft system powered by machine learning algorithm will be discussed.
基金supported by the grants from Program of China"Research of New Technology for Trauma Care and Integrated Demonstration"(2012BAI11B01)
文摘Background:Intra-abdominal hypertension(IAH) is a disease with high morbidity and mortality among critically ill patients.The study's objectives were to explore the prevalence of IAH and physicians' awareness of the 2013 World Society of Abdominal Compartment Syndrome(WSACS) guidelines in Chinese intensive care units(ICUs).Methods:A cross-sectional study of four ICUs in Southwestern China was conducted from June 17 to August 2,2014.Adult patients admitted to the ICU for more than 24 h,with bladder catheter but without obvious intravesical pressure(IVP) measurement contraindications,were recruited.Intensivists with more than 5 years of ICU working experience were also recruited.Epidemiological information,potential IAH risk factors,IVP measurements and questionnaire results were recorded.Results:Forty-one patients were selected.Fifteen(36.59%) had IVP?12mm Hg.SOFA(Sequential Organ Failure Assessment) hepatic and neurological sub-scores were utilized as independent predictors for IAH via logistic backward analysis.Thirty-seven intensivists participated in the survey(response rate:80.43%).The average score of each center was less than 35 points.All physicians believed the IAH prevalence in their departments was no more than 20.00%.A significant negative correlation was observed between the intensivists' awareness of the 2013 WSACS guidelines and the IAH prevalence in each center(r=-0.975,P=0.025).Conclusion:The prevalence and independent predictors of IAH among the surveyed population are similar to the reports in the literature.Intensivists generally have a low awareness of the 2013 WSACS guidelines.A systematic guideline training program is vital for improving the efficiency of the diagnosis and treatment of IAH.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11774088 and 11474090)。
文摘In high intensity focused ultrasound(HIFU)treatment,it is crucial to accurately identify denatured and normal biological tissues.In this paper,a novel method based on compressed sensing(CS)and refined composite multi-scale fuzzy entropy(RCMFE)is proposed.First,CS is used to denoise the HIFU echo signals.Then the multi-scale fuzzy entropy(MFE)and RCMFE of the denoised HIFU echo signals are calculated.This study analyzed 90 cases of HIFU echo signals,including 45 cases in normal status and 45 cases in denatured status,and the results show that although both MFE and RCMFE can be used to identify denatured tissues,the intra-class distance of RCMFE on each scale factor is smaller than MFE,and the inter-class distance is larger than MFE.Compared with MFE,RCMFE can calculate the complexity of the signal more accurately and improve the stability,compactness,and separability.When RCMFE is selected as the characteristic parameter,the RCMFE difference between denatured and normal biological tissues is more evident than that of MFE,which helps doctors evaluate the treatment effect more accurately.When the scale factor is selected as 16,the best distinguishing effect can be obtained.
文摘With the vigorous development of automobile industry,in-vehicle network is also constantly upgraded to meet data transmission requirements of emerging applications.The main transmission requirements are low latency and certainty especially for autonomous driving.Time sensitive networking(TSN)based on Ethernet gives a possible solution to these requirements.Previous surveys usually investigated TSN from a general perspective,which referred to TSN of various application fields.In this paper,we focus on the application of TSN to the in-vehicle networks.For in-vehicle networks,we discuss all related TSN standards specified by IEEE 802.1 work group up to now.We further overview and analyze recent literature on various aspects of TSN for automotive applications,including synchronization,resource reservation,scheduling,certainty,software and hardware.Application scenarios of TSN for in-vehicle networks are analyzed one by one.Since TSN of in-vehicle network is still at a very initial stage,this paper also gives insights on open issues,future research directions and possible solutions.
基金supported by the Natural Science Foundation of Anhui Province (Grant No. 2008085MF217, Grant No. 2008085QF287)the University Natural Science Research Project of Anhui Province (Grant No. KJ2021A0912, Grant No. KJ2020A0091, Grant No. KJ2019A0714)+1 种基金the Program Fund for Excellent Young Talents of Higher Education Institutions of Anhui Province (Grant No. gxyq2020042)Anhui Province Key Laboratory of Simulation and Design for Electronic Information System (Grant No. 2019ZDSYSZB02)
文摘A porous 3D cross-linked conductive network pierced by multi-wall carbon nanotubes(MWCNTs) was successfully designed from zeolitic imidazolate framework-8(ZIF-8). Zn@NPC@MWCNTs composites were tailored by the facile regulating the mass ratios and thermal annealing treatment. Due to the combination of less eddy current loss and dielectric loss together with multiple reflection attenuation caused by a unique structure. With a 10 wt% filler loading, the Zn@NPC@MWCNTs composites carbonized at 800℃ show two high reflection loss(RL) values with different thicknesses. An RL value is-53.18 dB with 4.09 mm thickness in the C-Band(4-8 GHz), and a minimum RL can reach-74.83 d B(10.8 GHz)with a matching thickness of 2.749 mm. The effective absorption bandwidth is 4 GHz(from 8 to 12 GHz,RL ≤-10 d B), which just covers the full X-band. Low cost and easy preparation can also provide advantages to develop MOF-based materials as effective EMW absorbents.
基金funded by the National Natural Science Foundation of China (nos.21776273 21721004+6 种基金 21690080 21690082)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB17020100)the National Key Projects for Fundamental Research and Development of China (2016YFA0202801)Dalian Science Foundation for Distinguished Young Scholars (no.2015R005)Department of Science and Technology of Liaoning Province (under contract of 2015020086-101)100-talent project of Dalian Institute of Chemical Physics (DICP)
文摘A new route was developed for the synthesis of renewable decalin with cyclopentanone which can be derived from lignocellulose.It was found that 1,2,3,4,5,6,7,8-octahydronaphthalene could be selectively produced by the hydrogenation/dehydration/rearrangement of [1,1-bi(cyclopentylidene)]-2-one(i.e.the selfaldol condensation product of cyclopentanone) over a dual-bed catalyst system.Among the investigated catalysts,the Ru/C and Amberlyst-15 resin exhibited the highest activities for the hydrogenation of [1,1-bi(cyclopentylidene)]-2-one to [1,1-bi(cyclopentan)]-2-ol and the dehydration/rearrangement of [1,1-bi(cyclopentan)]-2-ol to 1,2,3,4,5,6,7,8-octahydronaphthalene,respectively.Using Ru/C and Amberlyst-15 resin as the first bed and the second bed catalysts,1,2,3,4,5,6,7,8-octahydronaphthalene was directly produced in high carbon yield(83.7%) under mild conditions(393 K,1 MPa).After being hydrogenated,the1,2,3,4,5,6,7,8-octahydronaphthalene was converted to decalin which can be used as additive to improve the thermal stability and volumetric heat value of jet fuel.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11275099,11435006 and 11405130the Double First-Class University Construction Project of Northwest University
文摘By throwing a particle with electric charge and angular momentum into the black holes, much evidence shows that the naked singularity of some （3＋1）-dimensional black holes might be seen, which is not allowed in the weak cosmic censorship conjecture. In this study, we consider a （2＋1）-dimensional Peldan black hole and find that it could be destroyed under certain conditions in both extreme and near-extreme cases.
基金supported by the Sichuan Natural Science Foundation(2023NSFSC0422)the Petrochina's"14th Five-Year plan"Project(2021Dj2804).
文摘The transmission medium of natural gas gathering and transportation pipelines usually contains cor-rosive gases,which will cause serious corrosion on the inner wall of the pipelines when they coexist with water.Therefore,it is necessary to add corrosion inhibitor to form a protective film to protect the pipeline.The distribution of corrosion inhibitors in a gathering and transportation pipeline in Moxi gas field was studied by combining experiment and simulation.The Pearson function was used to calculate the experimental and simulation results,and the correlation was more than 80%,indicating a high degree of agreement.The simulation results show that:①The larger the pipe angle,filling speed and gas flow rate,the smaller the particle size,the better the distribution of corrosion inhibitor particles in the pipe.The filling amount will affect the concentration,but the distribution trend is unchanged;②A method to determine the filling mode based on the loss was proposed,and for this pipeline,the loss of corrosion inhibitor was determined to be 5.31×10^(-3) kg/s,and the flling amount was recommended to be adjusted to 2o L/h,which has certain guiding significance for the actual flling strategy of pipeline corrosion inhibitor.
基金supported by Foundation Research Project of Shaanxi Province in Natural Science (Grant No.2019JQ-919)Special Project of Education Department of Shaanxi Province in Natural Science (Grant No.20JK0635)Talent Foundation of Weinan Normal University (Grant No.201120039)。
文摘In the study of weak cosmic censorship conjectures(WCCC),some research finds that the Reissner-Nordström black hole might be destroyed by a test particle with particular mass and charge under some conditions,which means that the naked singularity of the black hole could be observed.This is not allowed in WCCC.We have never observed such naked singularities which should not exist in theory,so we need to find a proper way to protect the black hole from being destroyed by such particles.In this paper,we study a Reissner-Nordström black hole that is surrounded by quintessence(RN-Q)and find that the black hole would be stable and safe because of the effective potential barrier induced by the quintessence term.This result may also show in a sense that the quintessence might have more potential value.
