Boosting oxygen reduction activity and CO_(2) resistance on bismuth ferrite-based perovskite cathode for low-temperature solid oxide fuel cells below 600℃

Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(LT-SOFCs) is of great importance for the practical commercialization.Herein,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)FeO_(3-δ) perovskites as highly-active catalysts for LT-SOFCs.Sm doping can significantly enhance the electrocata lytic activity and chemical stability of cathode.At 600℃,Bi_(0.675)Sm_(0.025)Sr_(0.3)FeO_(3-δ)(BSSF25) cathode has been found to be the optimum composition with a polarization resistance of 0.098 Ω cm^2,which is only around 22.8% of Bi_(0.7)Sr_(0.3)FeO_(3-δ)(BSF).A full cell utilizing BSSF25 displays an exceptional output density of 790 mW cm^(-2),which can operate continuously over100 h without obvious degradation.The remarkable electrochemical performance observed can be attributed to the improved O_(2) transport kinetics,superior surface oxygen adsorption capacity,as well as O_(2)p band centers in close proximity to the Fermi level.Moreover,larger average bonding energy(ABE) and the presence of highly acidic Bi,Sm,and Fe ions restrict the adsorption of CO_(2) on the cathode surface,resulting in excellent CO_(2) resistivity.This work provides valuable guidance for systematic design of efficient and durable catalysts for LT-SOFCs.

Preparation and Performance of n-Dodecane Microencapsulated Phase Change Cold Storage Materials

Cold chain transportation is currently a hot research topic.Since the traditional refrigeration methods lead to the consumption of large amounts of energy,the search for new energy storage materials is a major trend.In the present contribution,n-dodecane/PMMA microencapsulated phase change materials were prepared by suspension polymerization for ice-temperature cold chain transportation and their preparation parameters were explored using the encapsulation ratio as optimization indicator.The results show that the n-dodecane-containing microcapsules have a maximum encapsulation ratio of 93.2%when using a core-to-wall ratio of 3:1,5%of emulsifier,30%of crosslinker,and 2000 rpm of emulsification speed.The phase transition temperature and enthalpy are-2℃and 195.9 kJ/kg,respectively.The microcapsules prepared with the optimized process parameters have good microscopic morphology,high energy storage efficiency,uniform particle size and good thermal stability,making them ideal materials for cold chain transportation.

Low ambient temperature and air pollution are associated with hospitalization incidence of coronary artery disease:Insights from a cross-sectional study in Northeast China

Background:Previous studies have established a link between fluctuations in climate and increased mortality due to coronary artery disease(CAD).However,there remains a need to explore and clarify the evidence for associations between meteorological changes and hospitalization incidences related to CAD and its subtypes,especially in cold regions.This study aimed to systematically investigate the relationship between exposure to meteorological changes,air pollutants,and hospitalization for CAD in cold regions.Methods:We conducted a cross-sectional study using hospitalization records of 86,483 CAD patients between January 1,2009,and December 31,2019.Poisson regression analysis,based on generalized additive models,was applied to estimating the influence of hospitalization for CAD.Results:Significant associations were found between low ambient temperature[-10℃,RR=1.65;95%CI:(1.28-2.13)]and the incidence of hospitalization for CAD within a lag of 0-14 days.Furthermore,O_(3)[95.50μg/m^(3),RR=12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.Furthermore,O_(3)[95.50μg/m^(3),RR=1.12;95%CI:(1.03-1.21)]and NO_(2)[48.70μg/m^(3),RR=1.0895%CI:(1.01-1.15)]levels were identified as primary air pollutants affecting the incidence of CAD,ST-segment-elevation myocardial infarction(STEMI),and non-STEMI(NSTEMI)within the same lag period.The effect curve of CAD hospitalization incidence significantly increased at lag days 2 and 4 when NO_(2)and O_(3)concentrations were higher,with a pronounced effect at 7 days,dissipating by lag 14 days.No significant associations were observed between exposure to PM,SO_(2),air pressure,humidity,or wind speed and hospitalization incidences due to CAD and its subtypes.Conclusion:Our findings suggest a positive correlation between short-term exposure to low ambient temperatures or air pollutants(O_(3)and NO_(2))and hospitalizations for CAD,STEMI,and NSTEMI.These results could aid the development of effective preparedness strategies for frequent extreme weather events and support clinical and public health practices aimed at reducing the disease burden associated with current and future abnormal weather events.

A Hybrid Biofuel and Triboelectric Nanogenerator for Bioenergy Harvesting

Various types of energy exist everywhere around us,and these energies can be harvested from multiple sources to power micro-/nanoelectronic system and even personal electronic products.In this work,we proposed a hybrid energy-harvesting system(HEHS)for potential in vivo applications.The HEHS consisted of a triboelectric nanogenerator and a glucose fuel cell for simultaneously harvesting biomechanical energy and biochemical energy in simulated body fluid.These two energy-harvesting units can work individually as a single power source or work simultaneously as an integrated system.This design strengthened the flexibility of harvesting multiple energies and enhanced corresponding electric output.Compared with any individual device,the integrated HEHS outputs a superimposed current and has a faster charging rate.Using the harvested energy,HEHS can power a calculator or a green light-emitting diode pattern.Considering the widely existed biomechanical energy and glucose molecules in the body,the developed HEHS can be a promising candidate for building in vivo self-powered healthcare monitoring system.

Correction to:A Hybrid Biofuel and Triboelectric Nanogenerator for Bioenergy Harvesting

In the original publication,the authors’contribution is missing in the acknowledgment section.The correct acknowledgement is provided in this correction.Also,in Fig.4,the second(c)after figure(d)should be read as(e).In Fig.5(i),the Y-axis label“Current(μA)”should be read as“Voltage”.

QUANTIFYING THE SHORT LIFETIME WITH TCSPC-FLIM:FIRST MOMENT VERSUS FITTING METHODS

Combing the time corelated single photon counting(TCSPC)with fuorescence lifetime imaging microscopy(FLIM)provides promising opportunities in revealing important information on the microenvironment of cells and tissues,but the applications are thus far mainly limited by the accuracy and precision of the TCSPC-FLIM technique.Here we present a comprehensive in-vestigation on the perforance of two data analysis methods,the first moment(M_(1))method and the conventional least squares(Fitting)method,in quantifying fuorescence lifetime.We found that the Mp method is more superior than the Fitting method when the lifetime is short(70-400ps)or the signal intensity is weak(<10^(3) photons).

Chromosome 6q deletion mapping in human ovarian tumor: a common deletion region between D6S1649 and D6S311

Objective： To explore the loss of heterozygosity（LOH） on chromosome 6q in ovarian cancer, and localize a minimum area in deletion region. Methods： 93 ovarian tumors were analyzed for LOH studies with 10 microsatellite markers spanning chromosome 6q. To further localize a minimum area in deletion region. Nineteen microsatellite markers were used to refined a minimum area. Results： Forty three tumors （46%） were demonstrated allelic losses, which spanned less than two megabase areas, franked by a distal marker D6S311 and a proximal marker D6S1649, and likely harbored ovarian tumor suppressor gene （s）. With analysis of density of LOH, increased DNA copy number at loci of 6q was demonstrated between D6S1649 and D6S311. Conclusion： It is possible that duplication after the allelic loss might be a main mechanism that leads to carcinogenesis in ovarian tumor. The refinement of these candidate tumor suppressor genes loci might facilitate future loss of heterozygosity studies and enable the isolation of candidate genes from this region.

Sources appointment and health risks of PM_(2.5)-bound trace elements in a coastal city of southeastern China

To gain a comprehensive understanding of sources and health risks of trace elements in an area of China with high population densities and low PM_(2.5)concentrations,15 trace elements(Al,K,Ca,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As,Sn,Ba,Pb)in PM_(2.5)were monitored from December 2020 to November 2021 in a representative city,Xiamen.The concentrations of trace elements in Xiamen displayed an obvious seasonal variation and were dominated by K,Fe,Al,Ca and Zn.Based on Positive Matrix Factorization analysis,source appointment revealed that the major sources of trace elements in Xiamen were traffic,dust,biomass and firework combustion,industrial manufacture and shipping emission.According to health risk assessment combined with the source appointment results,it indicated that the average noncarcinogenic risk was below the threshold and cancer risk of four hazardous metals(Cr,Ni,As,Pb)exceeded the threshold(10^(-6)).Traffic-related source had almost half amount of contribution to the health risk induced by PM_(2.5)-bound trace elements.During the dust transport period or Spring Festival period,the health risks exceeded an acceptable threshold even an order of magnitude higher,suggesting that the serious health risks still existed in low PM_(2.5)environment at certain times.Health risk assessment reminded that the health risk reduction in PM_(2.5)at southeastern China should prioritize traffic-related hazardous trace elements and highlighted the importance of controlling vehicles emissions in the future.

具有骨样微环境的压电催化可控矿化支架实现内源性骨再生

Orderly hierarchical structure with balanced mechanical,chemical,and electrical properties is the basis of the natural bone microenvironment.Inspired by nature,we developed a piezocatalytically-induced controlled mineralization strategy using piezoelectric polymer poly-L-lactic acid(PLLA)fibers with ordered micro-nano structures to prepare biomimetic tissue engineering scaffolds with a bone-like microenvironment(pcm-PLLA),in which PLLA-mediated piezoelectric catalysis promoted the in-situ polymerization of dopamine and subsequently regulated the controllable growth of hydroxyapatite crystals on the fiber surface.PLLA fibers,as analogs of mineralized collagen fibers,were arranged in an oriented manner,and ultimately formed a bone-like interconnected pore structure;in addition,they also provided bone-like piezoelectric properties.The uniformly sized HA nanocrystals formed by controlled mineralization provided a bone-like mechanical strength and chemical environment.The pcm-PLLA scaffold could rapidly recruit endogenous stem cells,and promote their osteogenic differentiation by activating cell membrane calcium channels and PI3K signaling pathways through ultrasound-responsive piezoelectric signals.In addition,the scaffold also provided a suitable microenvironment to promote macrophage M2 polarization and angiogenesis,thereby enhancing bone regeneration in skull defects of rats.The proposed piezocatalytically-induced controllable mineralization strategy provides a new idea for the development of tissue engineering scaffolds that can be implemented for multimodal physical stimulation therapy.

Atmospheric oxidation capacity and O_(3) formation in a coastal city of southeast China:Results from simulation based on four-season observation

The pollution of atmospheric ozone in China shows an obvious upward trend in the past decade.However,the studies on the atmospheric oxidation capacity and O_(3)formation in four seasons in the southeastern coastal region of China with the rapid urbanization remain limited.Here,a four-season field observation was carried out in a coastal city of southeast China,using an observation-based model combining with the Master Chemical Mechanism,to explore the atmospheric oxidation capacity(AOC),radical chemistry,O_(3)formation pathways and sensitivity.The results showed that the average net O_(3)production rate(14.55 ppbv/hr)in summer was the strongest,but the average O_(3)concentrations in autumn was higher.The AOC and ROx levels presented an obvious seasonal pattern with the maximum value in summer,while the OH reactivity in winter was the highest with an average value of 22.75 sec^(-1).The OH reactivity was dominated by oxygenated VOCs(OVOCs)(30.6%-42.8%),CO(23.2%-26.8%),NO_(2)(13.6%-22.0%),and alkenes(8.4%-12.5%)in different seasons.HONO photolysis dominated OH primary source on daytime in winter,while in other seasons,HONO photolysis in the morning and ozone photolysis in the afternoon contributed mostly.Sensitivity analysis indicated that O_(3)production was controlled by VOCs in spring,autumn and winter,but a VOC-limited and NOx-limited regime in summer,and alkene and aromatic species were the major controlling factors to O_(3)formation.Overall,the study characterized the atmospheric oxidation capacity and elucidated the controlling factors for O_(3)production in the coastal area with the rapid urbanization in China.

MODIFIED STOCHASTIC EXTRAGRADIENT METHODS FOR STOCHASTIC VARIATIONAL INEQUALITY

In this paper,we consider two kinds of extragradient methods to solve the pseudo-monotone stochastic variational inequality problem.First,we present the modified stochastic extragradient method with constant step-size(MSEGMC)and prove the convergence of it.With the strong pseudo-monotone operator and the exponentially growing sample sequences,we establish the R-linear convergence rate in terms of the mean natural residual and the oracle complexity O(1/ǫ).Second,we propose a modified stochastic extragradient method with adaptive step-size(MSEGMA).In addition,the step-size of MSEGMA does not depend on the Lipschitz constant and without any line-search procedure.Finally,we use some numerical experiments to verify the effectiveness of the two algorithms.

江苏省盐城市滨海县社区糖尿病患者慢性肾功能不全发病率及危险因素分析

目的探讨江苏省盐城市滨海县社区糖尿病患者慢性肾功能不全(CRI)的发病率及其危险因素。方法为回顾性队列研究。选取江苏省盐城市滨海县2018年1月1日—12月31日参与居民健康体检,并连续4年(截至2021年12月31日)完成每年1次体检随访的糖尿病患者为研究对象。收集患者一般资料(性别、年龄)、血液学指标[空腹血糖(FPG)、甘油三酯(TG)、总胆固醇(TC)、肌酐],尿蛋白定性结果(阴性、微量、1+、2+或3+;其中,中等量蛋白尿定义为尿蛋白1+,大量蛋白尿被定义为尿蛋白≥2+),并根据慢性肾脏病流行病学协作公式(CKD-EPI)计算估算的肾小球滤过率(eGFR)。CRI诊断标准为患者肾功能不全[eGFR<60 ml·min^(-1)·(1.73 m^(2))^(-1)]病史持续≥3个月。终点事件设定为患者在随访期间,首次出现肾功能不全,并通过后续门诊、查询电子病历系统或电话随访,调取参与者至少2次血清肌酐水平,证实患者符合CRI诊断。采用Poisson回归模型计算患者CRI发病率,采用多因素Cox回归分析评估糖尿病患者发生CRI的独立危险因素。结果最终纳入8244例糖尿病患者。基线时,患者年龄(62.2±9.1)岁,男性占39.3%(3238/8244)。中位随访时间为3.4(3.3,3.5)年,8.7%(715/8244)患者在随访期内发生CRI,CRI发病率为2.64(95%CI 2.60~2.67)/百人年。多因素Cox回归分析显示,女性(HR=1.634,95%CI 1.389~1.921)、TG增加(每增加1 mmol/L,HR=1.044,95%CI 1.014~1.075)、FPG增加(每增加1 mmol/L,HR=1.063,95%CI 1.040~1.087)、中等量蛋白尿(HR=1.290,95%CI 1.003~1.667)及大量蛋白尿(HR=2.086,95%CI 1.645~2.644)是新发CRI风险的独立危险因素。基线eGFR水平与CRI患病风险独立负相关[每增加5 ml·min^(-1)·(1.73 m^(2))^(-1),HR=0.623,95%CI 0.604~0.642]。结论社区糖尿病患者CRI发病率较高。女性、TG及FPG的升高、中等及大量蛋白尿、低eGFR与新发CRI风险独立相关。

有晶状体眼人工晶状体不同植入方向旋转稳定性的比较

目的:比较水平、斜向、垂直植入有晶状体眼人工晶状体(ICL)及水平植入散光型人工晶状体(TICL)在术后1个月、1年的旋转稳定性。方法:回顾性临床研究。连续性收集2020年1月至2021年6月在郑州爱尔眼科医院屈光手术专科行ICL(V4c)植入术的屈光不正患者92例(184眼)。根据术后1 d的人工晶状体(IOL)轴向分为ICL水平组、ICL斜向组、ICL垂直组和TICL水平组,分别为59、33、36、56眼。记录术后1 d、1个月和1年的裸眼视力、眼压、拱高及IOL轴向等,并计算术后1个月、1年的有效性指数和IOL旋转角度和方向。4组间术后各时间点有效性指数、眼压等计量资料的比较采用重复测量方差分析,IOL旋转角度组间比较采用Kruskal-Wallis检验,IOL旋转方向组间比较采用Pearsonχ^(2)检验。采用Spearman秩相关分析及多元线性回归分析术后1年IOL旋转角度与年龄、性别等指标之间的相关性。结果:ICL水平组、ICL斜向组、ICL垂直组与TICL水平组在术后1个月、1年组间有效性指数、眼压、拱高及角膜内皮细胞密度差异均无统计学意义(均P>0.05)。在术后1个月、1年,4组间IOL旋转角度差异均无统计学意义(H=6.36,P=0.095;H=4.82,P=0.185);IOL旋转方向差异亦无统计学意义(χ^(2)=4.44,P=0.617;χ^(2)=6.03,P=0.420)。术后1年IOL旋转角度与患者年龄、性别等指标均无相关性(均P>0.05)。结论:ICL水平、斜向、垂直植入与TICL水平植入在术后1个月和1年均可获得相对一致的手术效果和旋转稳定性。

Intrapulse coherence degradation suppressing method of echo signal in coherent lidar

Aiming at coherence degradation during target detection,a suppressing method based on frequency-modulated continuous wave coherent lidar is proposed.Combined with a random iteration algorithm,a long-pulse echo signal with coherent degradation is matched with random phase noise of a certain frequency and achieves coherence restoration.Simulation and field experiment results show that this proposed method can recover the intrapulse coherence in long-pulse echo signals.In addition,for the real target echo signal at 4.2 and 19.8 km,the peak signal-to-noise ratio processed by this method is increased by 0.35 times and 4 times after pulse compression,respectively.

Genetic Architecture and Functional Implications of the CSF‑Contacting Nucleus

We previously identified a unique nucleus,the cerebrospinal fluid(CSF)-contacting nucleus.This study aims to understand its gene architecture and preliminarily suggest its functions.The results showed that there were about 19,666 genes in this nucleus,of which 913 were distinct from the dorsal raphe nucleus(non-CSF contacting).The top 40 highly-expressed genes are mainly related to energy metabolism,protein synthesis,transport,secretion,and hydrolysis.The main neurotransmitter is 5-HT.The receptors of 5-HT and GABA are abundant.The channels for Cl–,Na+,K+,and Ca2+are routinely expressed.The signaling molecules associated with the CaMK,JAK,and MAPK pathways were identified accurately.In particular,the channels of transient receptor potential associated with nociceptors and the solute carrier superfamily members associated with cell membrane transport were significantly expressed.The relationship between the main genes of the nucleus and life activities is preliminarily verified.

Highly lipophilic coumarin fluorophore with excimer-monomer transition property for lipid droplet imaging

Lipid droplet(LD) fluorescent imaging plays an important role in the detection of lipid-related diseases.Due to their poor photostability and low hydrophobicity of currently available LD imaging fluorophores,LD imaging is limited by its short imaging period and low imaging contrast. Herein, we reasonably designed a highly lipophilic compound Cou-Flu with excellent photostability and excimer-monomer transition property. It exhibited weak excimer emission in cytoplasm, but strong monomer emission in LDs,enabling high contrast LD imaging and LD movement tracing in cells. Zebrafish imaging study demonstrated that Cou-Flu was also suitable for in vivo LD detection with excellent sensitivity. We anticipate that Cou-Flu could be widely applied to understand LD-related intracellular activities and even LD-related diseases in the future.

Emerging trends in materials and devices-based electric stimulation therapy for tumors

Electrical stimulation(ES),as one of the physical therapy modalities for tumors,has attracted extensive attention of researchers due to its promising efficacy.With the continuous development of material science,nanotechnology,and micro/nano processing techniques,novel electroactive nanomaterials and delicately designed devices have emerged to realize innovative ES therapies,which provide more possibilities and approaches for tumor treatment.Meanwhile,exploring the molecular biological mechanisms underlying different ES modalities affecting tumor cells and their immune microenvironment is also an unresolved hotspot emerging from the current biomedical engineering research.Focusing on the above research interests,in this review,we systematically summarized the effects of different ES parameters on the subcellular structure of tumor cells and the tumor immune microenvironment(TIME)in conjunction with the involved signaling pathways.In addition,we also reviewed the latest progress in novel self-powered devices and electroactive nanomaterials for tumor therapy.Finally,the prospects for the development of electrostimulation tumor therapy are also discussed,bringing inspiration for the development of new physical therapy strategies in the future.

雷公藤红素抑制成人T细胞白血病细胞增殖及机制

本研究旨在分析雷公藤红素对成人T细胞白血病细胞增殖、凋亡的影响,并探讨其分子机制。使用不同浓度的雷公藤红素溶液处理多种成人T细胞白血病细胞株,通过四唑盐比色法(MTT)、克隆形成实验检测细胞的增殖情况;Annexin V/PI双染检测细胞凋亡情况;最后通过Western blotting及双荧光素酶报告基因技术探究雷公藤红素抑制成人T细胞白血病细胞生长的调控机制。结果表明雷公藤红素能显著抑制成人T细胞白血病细胞增殖并诱导其凋亡,随着雷公藤红素浓度的增加Bax/Bcl-2蛋白比率明显升高,凋亡途径中Caspase-3/7蛋白也随之被切割活化,同时病毒编码的癌蛋白Tax的表达也明显受到抑制。以上结果表明,雷公藤红素通过调控Bcl-2家族蛋白,激活了Caspase途径诱导细胞凋亡,并通过抑制病毒关键蛋白Tax的表达,从而有效抑制了成人T细胞白血病细胞的增殖。该研究为临床应用雷公藤红素治疗成人T细胞白血病提供了实验依据。

Pollution characteristics of organic and elemental carbon in PM_(2.5) in Xiamen,China

Xiamen, located on the southeastern coastal line of China, is undergoing rapid urbanization and industrialization, so its air quality has a trend of degradation. However, studies on level, temporal and spatial changes of fine particles （PM2.5） and their carbonaceous fractions are scarce. In this article, abundance, sources, seasonal and spatial variations, distribution of organic carbon （OC） and elemental carbon （EC） in PM2.5, were studied at suburban, urban and industrial sites in Xiamen during four season-representative months in 2009-2010. PM2.5 samples were collected with middle volume sampler and were analyzed for OC and EC with thermal optical transmittance （TOT） method. Results showed that the annual average PM2.5 concentrations were 63.88-74.80 Ixg/m3 at three sites. While OC and EC concentrations were in the range of 15.81-19.73 [xg/m3 and 2.74-3.49 ~tg/m3, respectively, and clearly presented the summer minima and winter maxima in this study. The carbonaceous aerosol accounted for 42.8%-47.3% of the mass of PMzs. The annual average of secondary organic carbon （SOC） concentrations in Xiamen were 9.23-11.36 ~g/m3, accounting for approximately 56% of OC. Strong correlations between OC and EC was found in spring （R2 = 0.50） and autumn （R2 = 0.73）, suggesting that there were similar emission and transport processes for carbonaceous aerosols in these two seasons, while weak correlations were found in summer （R2 = 0.33） and winter （R2 = 0.41）. The OCI＇EC ratios in PM2.5 varied from 2.1 to 8.7 with an annual average of 5.7, indicating that vehicle exhaust, coal smoke and biomass burning were main source apportionments of carbonaceous fractions in Xiamen.

Chemical compositions of PM_(2.5) aerosol during haze periods in the mountainous city of Yong'an, China

Haze phenomena were found to have an increasing tendency in recent years in Yong＇an, a mountainous industrial city located in the center part of Fujian Province, China. Atmospheric fine particles （PM2.5） in the urban area during haze periods in three seasons （spring, autumn and winter） from 2007 to 2008 were collected, and the mass concentrations and chemical compositions （seventeen elements, water soluble inorganic ions （WSIIs） and carbonaceous species） of PM2.5 were determined. PM2.5 mass concentrations did not show a distinct difference among the three seasons. The carbonaceous species organic carbon （OC） and elemental carbon （EC） constituted up to 19.2%-30.4% of the PM2.5 mass during sampling periods, while WSIIs made up 25.3%-52.5% of the PM2.5 mass. The major ions in PM2.5 were SO42-, NO3- and NH4~, while the major elements were Si, K, Pb, Zn, Ca and A1. The experimental results （from data based on three haze periods with a 10-day sampling length for each period） showed that the crustal element species was the most abundant component of PM2.5 in spring, and the secondary ions species （SO42-, NO3-, NH4＋, etc.） was the most abundant component in PM2.5 in autumn and winter. This indicated that dust was the primary pollution source for PM2.5 in spring and combustion and traffic emissions could be the main pollution sources for PM2.5 in autumn and winter. Generally, coal combustion and traffic emissions were considered to be the most prominent pollution sources for this city on haze days.