A CNN-Based Single-Stage Occlusion Real-Time Target Detection Method

Aiming at the problem of low accuracy of traditional target detection methods for target detection in endoscopes in substation environments, a CNN-based real-time detection method for masked targets is proposed. The method adopts the overall design of backbone network, detection network and algorithmic parameter optimisation method, completes the model training on the self-constructed occlusion target dataset, and adopts the multi-scale perception method for target detection. The HNM algorithm is used to screen positive and negative samples during the training process, and the NMS algorithm is used to post-process the prediction results during the detection process to improve the detection efficiency. After experimental validation, the obtained model has the multi-class average predicted value (mAP) of the dataset. It has general advantages over traditional target detection methods. The detection time of a single target on FDDB dataset is 39 ms, which can meet the need of real-time target detection. In addition, the project team has successfully deployed the method into substations and put it into use in many places in Beijing, which is important for achieving the anomaly of occlusion target detection.

Conditioned medium from human dental pulp stem cells treats spinal cord injury by inhibiting microglial pyroptosis

Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery after spinal cord injury remains unclear.In the present study,we established a rat model of spinal cord injury based on impact injury from a dropped weight and then intraperitoneally injected the rats with conditioned medium from human dental pulp stem cells.We found that the conditioned medium effectively promoted the recovery of sensory and motor functions in rats with spinal cord injury,decreased expression of the microglial pyroptosis markers NLRP3,GSDMD,caspase-1,and interleukin-1β,promoted axonal and myelin regeneration,and inhibited the formation of glial scars.In addition,in a lipopolysaccharide-induced BV2 microglia model,conditioned medium from human dental pulp stem cells protected cells from pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway.These results indicate that conditioned medium from human dental pulp stem cells can reduce microglial pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway,thereby promoting the recovery of neurological function after spinal cord injury.Therefore,conditioned medium from human dental pulp stem cells may become an alternative therapy for spinal cord injury.

我国中医药科技创新面临的挑战及发展举措

中医药学是我国具有原创优势的医疗与科技资源。党的十八大以来,国家中医药科学研究水平和科技创新能力显著提升,极大地促进了中医药的传承创新和发展。但是,中医药研究和科技创新也面临着资金投入少、研究平台层级低、研究队伍知识结构单一、前沿技术整合能力不足、研究项目碎片化、国际合作规模小、层次低等种种问题。本文从中医药科技创新现状出发,指出了我国中医药发展所面临的产品开发、独特技术流失和原创理论开发价值被流失的“三大”挑战。为了确保我国中医药原创理论的科学研究、价值开发、科技创新、产业发展等全方位的国际主导权,提出亟需重点构建“三大研究体系”,即新型中医病证结合临床诊疗体系、中医证候治疗药理学研究体系、中医临床研究底层支撑技术与方法学体系,并就上述体系构建的关键科学问题、重点任务、解决途径与方法进行了提炼,希望能为未来中医药研究和科技创新的重点布局提供参考。

Physics package based on intracavity laser cooling ^(87)Rb atoms for space cold atom microwave clock

This article proposes a new physics package to enhance the frequency stability of the space cold atom clock with the advantages of a microgravity environment. Clock working processes, including atom cooling, atomic state preparation,microwave interrogation, and transition probability detection, are integrated into the cylindrical microwave cavity to achieve a high-performance and compact physics package for the space cold atom clock. We present the detailed design and ground-test results of the cold atom clock physics package in this article, which demonstrates a frequency stability of 1.2×10^(-12) τ^(-1/2) with a Ramsey linewidth of 12.5 Hz, and a better performance is predicted with a 1 Hz or a narrower Ramsey linewidth in microgravity environment. The miniaturized cold atom clock based on intracavity cooling has great potential for achieving space high-precision time-frequency reference in the future.

Isogeometric Analysis of Hyperelastic Material Characteristics for Calcified Aortic Valve

This study explores the implementation of computed tomography(CT)reconstruction and simulation techniques for patient-specific valves,aiming to dissect the mechanical attributes of calcified valves within transcatheter heart valve replacement(TAVR)procedures.In order to facilitate this exploration,it derives pertinent formulas for 3D multi-material isogeometric hyperelastic analysis based on Hounsfield unit(HU)values,thereby unlocking foundational capabilities for isogeometric analysis in calcified aortic valves.A series of uniaxial and biaxial tensile tests is executed to obtain an accurate constitutive model for calcified active valves.To mitigate discretization errors,methodologies for reconstructing volumetric parametric models,integrating both geometric and material attributes,are introduced.Applying these analytical formulas,constitutive models,and precise analytical models to isogeometric analyses of calcified valves,the research ascertains their close alignment with experimental results through the close fit in displacement-stress curves,compellingly validating the accuracy and reliability of the method.This study presents a step-by-step approach to analyzing themechanical characteristics of patient-specific valves obtained fromCT images,holding significant clinical implications and assisting in the selection of treatment strategies and surgical intervention approaches in TAVR procedures.

Bimodal growth of Fe islands on graphene

Magnetic metals deposited on graphene hold the key to applications in spintronics. Here, we present the results of Fe islands grown on graphene/Si C(0001) by molecular beam epitaxy, which are investigated by scanning tunneling microscopy. The two types of islands distinguished by flat or round tops are revealed, indicating bimodal growth of Fe. The atomic structures on the top surfaces of flat islands are also clearly resolved. Our results may improve the understanding of the mechanisms of metals deposited on graphene and pave the way for future spintronic applications of Fe/graphene systems.

The tri-band high spectral resolution spectrometer with gratings in tandem for the charge-exchange recombination spectroscopy diagnostic system on HL-2A tokamak

Charge-exchange(CX) recombination spectroscopy is a powerful tool monitoring ion temperature and plasma rotation with good temporal and spatial resolutions. A compact, new design for a high-throughput, tri-band high spectral resolution spectrometer has been developed for the charge-exchange recombination spectroscopy measurement on the HL-2A tokamak. The simultaneous measurements of He II(468.57 nm), C VI(529.1 nm), and Dα(656.1 nm accompanied by beam emission spectra) with an acquisition frequency up to 400 Hz are achieved by vertically binning the spectrum from each fiber in experiments. Initial results indicate that the system can provide radial profiles of not only ion temperature and rotation velocity,but also concentration of carbon. For the case of helium, the measurements for the ion temperature and rotation velocity are straightforward but the apparent concentration associated with the observed CX intensity is obviously too high. Modeling of the active He II CX feature including plume contributions needs to be carried out to extract the true helium concentration.The spectrometer could become a prototype for the ITER charge-exchange recombination spectroscopy diagnostic and the pilot experiments, as presented here, demonstrate the possibility of impurity concentrations measurements based on the combined measurement of local beam emission and charge-exchange recombination spectroscopy spectra.

Fatal multiple acyl-CoA dehydrogenase deficiency caused by ETFDH gene mutation:A case report

BACKGROUND Multiple acyl-CoA dehydrogenase deficiency(MADD)is a disease of rare autosomal recessive disorder.There are three types of MADD.Type I is a neonatalonset form with congenital anomalies.Type II is a neonatal-onset form without congenital anomalies.Type III is considered to a milder form and usually responds to riboflavin.However,late-onset form could also be fatal and not responsive to treatments.CASE SUMMARY We report a severe case of a young man with onset type III MADD induced by drugs and strenuous exercise characterized by rhabdomyolysis and liver dysfunction.Urine analysis indicated 12 out of 70 kinds of organic acids like glutaric acid-2 were detected.Serum analysis in genetic metabolic diseases revealed 24 out of 43 tested items were abnormal,revealing the elevation of several acylcarnitines and the reduction of carnitine in the patient.By next generation sequencing technology for gene sequencing related to fatty acid oxidation and carnitine cycle defects,a rare ETFDH gene variant was identified:NM_004453:4:C.1448C>T(p.Pro483 Leu).The patient was diagnosed with lateonset GAII.He was not responsive to riboflavin and progressively worsened into multiple organ failure that finally led to death.CONCLUSION Type III MADD can also be fatal and not responsive to treatments.

Coordinated Voltage Control of Distribution Network ConsideringMultiple Types of Electric Vehicles

The couple between the power network and the transportation network(TN)is deepening gradually with the increasing penetration rate of electric vehicles(EV),which also poses a great challenge to the traditional voltage control scheme.In this paper,we propose a coordinated voltage control strategy for the active distribution networks considering multiple types of EV.In the first stage,the action of on-load tap changer and capacitor banks,etc.,are determined by optimal power flow calculation,and the node electricity price is also determined based on dynamic time-of-use tariff mechanism.In the second stage,multiple operating scenarios of multiple types of EVs such as cabs,private cars and buses are considered,and the scheduling results of each EV are solved by building an optimization model based on constraints such as queuing theory,Floyd-Warshall algorithm and traffic flow information.In the third stage,the output power of photovoltaic and energy storage systems is fine-tuned in the normal control mode.The charging power of EVs is also regulated in the emergency control mode to reduce the voltage deviation,and the amount of regulation is calculated based on the fair voltage control mode of EVs.Finally,we test the modified IEEE 33-bus distribution system coupled with the 24-bus Beijing TN.The simulation results show that the proposed scheme can mitigate voltage violations well.

Analysis of Municipal Water Supply and Drainage Pipe Design Technology

The quality and safety of residents’water rely heavily on the design of municipal water supply and drainage pipes.Therefore,this paper aims to enhance the optimization of municipal water supply and drainage pipe design by focusing on design requirements,principles,and key elements.Drawing from relevant design optimization experiences,technology advancements,and optimization measures,the research will analyze and consolidate the essential aspects of municipal water supply and drainage pipe design.The goal is to fundamentally elevate the quality standards of these designs,ensuring they meet the criteria for engineering project excellence.Through this comprehensive approach,we aim to contribute to the improvement and sustainability of water supply and drainage systems,safeguarding the well-being of residents.

Analysis of Roadbed Splicing at Hub Interchanges

This article discusses the roadbed splicing for hub interchanges.The article starts with a description of the characteristics of junction roadbed splicing.The application of splicing technology is explained using a subgrade splicing scheme of a project.Roadbed splicing involves stepwise excavation and preparative measures like surface cleaning and backfilling.This article serves to provide a valuable reference for road and bridge construction and improve the quality of China’s road and bridge projects,so as to achieve sustainable development of the road and bridge engineering industry.

Selection of Water Transmission Method and Analysis of Pipe Network Zoning in Municipal Water Supply and Drainage Design

With the acceleration of urbanization,the demand for water supply and drainage pipe networks has increased significantly.In the planning of urban construction,it is necessary to optimize the design of the water supply and drainage system pipe network to effectively save energy while providing residents with more accessible water resources.Therefore,the municipal water supply and drainage system and the water transmission methods should be designed according to the geographical conditions of the city.In this paper,we mainly analyze the design of municipal water supply and drainage systems and the selection of water transmission methods.Besides,the optimization of the water supply and drainage network zoning process and pipe network maintenance is also discussed,so as to provide a reference for municipal water supply and drainage work.

基于网格单元和随机森林的滑坡易发性评价

主要提出基于网格化单元和随机森林模型评价江西省赣州市滑坡易发性。结合前人研究与研究区概况,选取10个影响因子用于评价赣州市滑坡易发性,利用随机森林模型与ArcGIS平台得出赣州市滑坡易发性分级图,模型AUC值为0.86,经验证,模型准确率达90%。结果表明:赣州市滑坡灾害分布不均,整体滑坡易发性不高,低易发区和较低易发区共同占比55.31%。高风险区和较高风险区主要集中于兴国县、瑞金市、会昌县、龙南县、大余县、于都县东北部、宁都县西南部和信丰县南部,其余区县有少量分布。

Vav1 promotes inflammation and neuronal apoptosis in cerebral ischemia/reperfusion injury by upregulating microglial and NLRP3 inflammasome activation

Microglia,which are the resident macrophages of the central nervous system,are an important part of the inflammatory response that occurs after cerebral ischemia.Vav guanine nucleotide exchange factor 1(Vav1) is a guanine nucleotide exchange factor that is related to microglial activation.However,how Vav1 participates in the inflammato ry response after cerebral ischemia/reperfusion inj ury remains unclea r.In this study,we subjected rats to occlusion and repe rfusion of the middle cerebral artery and subjected the BV-2 mic roglia cell line to oxygen-glucose deprivatio n/reoxygenation to mimic cerebral ischemia/repe rfusion in vivo and in vitro,respectively.We found that Vav1 levels were increased in the brain tissue of rats subjected to occlusion and reperfusion of the middle cerebral arte ry and in BV-2 cells subjected to oxygen-glucose deprivation/reoxygenation.Silencing Vav1 reduced the cerebral infarct volume and brain water content,inhibited neuronal loss and apoptosis in the ischemic penumbra,and im p roved neurological function in rats subjected to occlusion and repe rfusion of the middle cerebral artery.Further analysis showed that Vav1 was almost exclusively localized to microglia and that Vav1 downregulation inhibited microglial activation and the NOD-like receptor pyrin 3(NLRP3) inflammasome in the ischemic penumbra,as well as the expression of inflammato ry facto rs.In addition,Vov1 knoc kdown decreased the inflammatory response exhibited by BV-2 cells after oxygen-glucose deprivation/reoxyge nation.Taken together,these findings show that silencing Vav1 attenuates inflammation and neuronal apoptosis in rats subjected to cerebral ischemia/repe rfusion through inhibiting the activation of mic roglia and NLRP3 inflammasome.

基于宏基因组技术研究哈蟆油对大鼠肠道菌群的影响

目的基于宏基因组技术研究哈蟆油(OR)对大鼠肠道菌群的影响,用组学技术表征OR的功效。方法雄性SD大鼠随机分为对照组和OR组。OR组大鼠以200 mg·kg^(-1)剂量的OR匀浆每日灌胃,对照组以等体积生理盐水灌胃。14 d后,采集大鼠粪便进行宏基因组测序,对测序结果进行基因预测、丰度分析、物种注释及京都基因与基因组百科全书(KEGG)功能注释。结果在门水平上OR可以显著升高放线菌门相对丰度(P<0.05),在纲水平上OR可以显著升高放线菌纲相对丰度(P<0.05),在目水平上OR可以显著升高双歧杆菌目相对丰度(P<0.05)。两组大鼠肠道菌群在门和属水平上的β多样性存在差异。线性判别效应大小分析(LEfSe)筛选出两组间35种显著差异菌种。KEGG功能注释结果显示,在Level 1层级上注释到新陈代谢类通路的基因最多。组间差异分析表明,OR组注释到免疫系统、环境适应及癌症相关通路的相对丰度产生变化。结论改变大鼠肠道菌群相对丰度及多样性、调节脂质及氨基酸代谢通路可能是OR营养保健和治疗疾病的潜在机制。

LC-MS/MS法定量分析人血清中多黏菌素B的浓度

目的开发一种简单灵敏的液相色谱串联质谱法(LC-MS/MS)用于人血清中多黏菌素B(PB)的浓度测定。方法用多黏菌素E_(2)(PE_(2))作为内标,使用乙腈(含0.1%甲酸)沉淀蛋白质法处理样品。采用Hypersil GOLD^(TM)C_(18)色谱柱进行色谱分析。流动相A为0.1%甲酸-水,流动相B为纯甲醇,梯度洗脱;流速:0.4 mL·min^(-1),进样量:2μL,分析时间:3.3 min,柱温:40℃。采用多反应监测模式,电喷雾离子源正离子模式进行定量分析。定量离子对分别为m/z 402.10>101.10(PB_(1)),m/z 397.45>101.10(PB_(2)),m/z 578.50>101.10(PE_(2))。结果人血清中PB_(1)在22~15000 ng·mL^(-1),PB_(2)在5~1700 ng·mL^(-1)范围内线性关系良好,相关系数均大于0.9990。PB_(1)和PB_(2)的定量下限分别为22,5 ng·mL^(-1)。PB_(1)的准确度为95.98%~104.60%,PB_(2)的准确度为98.11%~105.59%;批内和批间精密度的RSD均小于15%。PB_(1)和PB_(2)的提取回收率分别为97.26%~103.31%和95.81%~101.22%;基质效应分别为96.52%~109.54%和93.29%~109.95%。样品稳定性试验的RSD均小于15%。应用本方法测定的6例患者平均AUC_(0-24h)为(72.85±17.87)mg·h·L^(-1)。结论建立的测定人血清中PB浓度的LC-MS/MS方法符合生物样本检测分析的要求,适用于临床上PB血药浓度检测。

Single-atomic tungsten-doped Co_(3)O_(4) nanosheets for enhanced electrochemical kinetics in lithium–sulfur batteries

The practical application of lithium–sulfur batteries(LSBs)is severely hindered by the undesirable shuttling of lithium polysulfides(LiPSs)and sluggish redox kinetics of sulfur species.Herein,a series of ultrathin singleatomic tungsten-doped Co_(3)O_(4)(Wx-Co_(3)O_(4))nanosheets as catalytic additives in the sulfur cathode for LSBs are rationally designed and synthesized.Benefiting from the enhanced catalytic activity and optimized electronic structure by W doping,the Wx-Co_(3)O_(4) not only reduces the shuttling of LiPSs but also decreases the energy barrier of sulfur redox reactions of sulfur species,leading to accelerated electrode kinetic.As a result,LSB cathodes with the use of 5.0 wt%W0.02-Co_(3)O_(4) as the electrocatalyst show the high reversible capacities of 1217.0 and 558.6 mAh g^(-1) at 0.2 and 5.0 C,respectively,and maintain a high reversible capacity of 644.6 mAh g^(-1) at 1.0 C(1.0 C=1675 mA g^(-1))after 500 cycles.With a high sulfur loading of 5.5 mg cm^(-2) and electrolyte–electrode ratio of 8μL_(electrolyte) mg_(sulfur)^(-1),the 5.0 wt%W_(0.02)-Co_(3)O_(4)-based sulfur cathode also retains a high reversible areal capacity of 3.86 mAh cm^(-2) at 0.1 C after 50 cycles with an initial capacity retention of 84.7%.

Laser patterning of large-scale perovskite single-crystal-based arrays for single-mode laser displays

Lead halide perovskites have attracted considerable attention as potential candidates for high-performance nano/microlasers,owing to their outstanding optical properties.However,the further development of perovskite microlaser arrays(especially based on polycrystalline thin films)produced by the conventional processing techniques is hindered by the chemical instability and surface roughness of the perovskite structures.Herein,we demonstrate a laser patterning of large-scale,highly crystalline perovskite single-crystal films to fabricate reproducible perovskite single-crystal-based microlaser arrays.Perovskite thin films were directly ablated by femtosecond-laser in multiple low-power cycles at a minimum machining line width of approximately 300 nm to realize high-precision,chemically clean,and repeatable fabrication of microdisk arrays.The surface impurities generated during the process can be washed away to avoid external optical loss due to the robustness of the single-crystal film.Moreover,the high-quality,large-sized perovskite single-crystal films can significantly improve the quality of microcavities,thereby realizing a perovskite microdisk laser with narrow linewidth(0.09 nm)and low threshold(5.1µJ/cm2).Benefiting from the novel laser patterning method and the large-sized perovskite single-crystal films,a high power and high color purity laser display with single-mode microlasers as pixels was successfully fabricated.Thus,this study may offer a potential platform for mass-scale and reproducible fabrication of microlaser arrays,and further facilitate the development of highly integrated applications based on perovskite materials.

Constraining the Spatial Curvature of the Local Universe with Deep Learning

We use the distance sum rule method to constrain the spatial curvature of the Universe with a large sample of 161strong gravitational lensing systems,whose distances are calibrated from the Pantheon compilation of typeⅠa supernovae using deep learning.To investigate the possible influence of mass model of the lens galaxy on constraining the curvature parameterΩ_(k),we consider three different lens models.Results show that a flat Universe is supported in the singular isothermal sphere(SIS)model with the parameterΩ_(k)=0.049_(-0.125)^(+0.147).While in the power-law(PL)model,a closed Universe is preferred at the~3σconfidence level,with the parameterΩ_(k)=-0.245_(-0.071)^(+0.075).In the extended PL model,the 95%confidence level upper limit ofΩ_(k)is<0.011.As for the parameters of the lens models,constraints on the three models indicate that the mass profile of the lens galaxy could not be simply described by the standard SIS model.

Shale porosity measurement by the saturated oil method: Removing the contribution from oils dissolved in kerogen

Shale porosity measurements have crucial scientific and economical applications in unconventionalpetroleum systems. As a standard technique, liquid saturation methods, including water saturation (WS)and oil saturation (OS), have been widely used to measure the porosity of many rock types. For clay-richshale reservoirs with high organic matter content, it is well known that the WS method may cause clayswelling and induce structural changes in the pore system. The OS method affects the accuracy ofporosity measurements because of some of the oil being dissolved by kerogen within the shale;however,this has not received sufficient research attention. In this study, we compare the previously reported andnewly tested OS porosities with helium (He) expansion porosity. Results show that OS porosity generallyexceeds the He porosity. Furthermore, the higher the total organic carbon (TOC) content and lower thematurity of shale, the greater the difference between the OS and helium porosities. When using the OSmethod, the effect of kerogen-dissolved oil causes an overestimation of the shale porosity by ~30%. To thebest of our knowledge, this is the first time to note the kerogen-dissolve oil effects on OS porosity. Herein,we propose a new, simple, and effective correction method for estimating OS porosity that involvessubtracting the kerogen-dissolved oil content from raw OS porosity. In addition, the quantification modelof kerogen-dissolved oil capacity is established, taking into account the abundance and maturity oforganic matter. Taking the He porosity as the benchmark, the absolute error of the corrected OS porositydoes not exceed 1% and the average relative error is only ~10%. The obtained results can help improve theaccuracy of shale porosity evaluation methods.