丹参素对UVB诱导的皮肤光老化小鼠的保护作用和抗氧化机制研究

研究丹参素(DSS)对紫外线B(UVB)诱导的皮肤光老化(SP)小鼠的保护作用和抗氧化机制。建立了UVB诱导的SP小鼠模型,使用3个剂量的DSS(20,40和80 mg/(kg·d))治疗小鼠8周,结束后分别测定了各组小鼠的表皮含水量。通过HE染色评价皮肤组织形态,Masson三色染色评价胶原蛋白沉积。按照试剂盒说明测定皮肤组织中氧化应激指标(SOD、CAT、GSH-Px和MDA)和炎症指标(TNF-α和IL-6)水平。通过RT-qPCT和Western blotting检测了皮肤组织中MMP-1、Collagen I、Nrf2、Keap1、HO-1、NF-κB p65和p-NF-κB p65的mRNA或蛋白水平。结果显示,DSS剂量依赖性地提高了UVB诱导的SP小鼠表皮含水量,减轻皮肤损伤,促进胶原形成(P<0.05)。DSS抑制了UVB诱导的SP小鼠皮肤组织中MMP-1的转录和表达,促进了Collagen的转录和表达(P<0.05)。DSS升高了UVB诱导的SP小鼠皮肤组织中SOD、CAT和GSH-Px的水平,降低了MDA的水平(P<0.05)。DSS降低了UVB诱导的SP小鼠皮肤组织中TNF-α和IL-6的水平(P<0.05)。DSS促进了UVB诱导的SP小鼠皮肤组织中Nrf2和HO-1的转录和表达,抑制了Keap1的转录和表达(P<0.05)。DSS抑制了UVB诱导的SP小鼠皮肤组织中p-NF-κB p65的表达(P<0.05)。本研究表明DSS可有效改善UVB诱导的小鼠SP,其机制与Nrf2和NF-κB信号通路有关。

GNAS mutations suppress cell invasion by activating MEG3 in growth hormone–secreting pituitary adenoma

Approximately 30%–40%of growth hormone–secreting pituitary adenomas(GHPAs)harbor somatic activating mutations in GNAS(αsubunit of stimulatory G protein).Mutations in GNAS are associated with clinical features of smaller and less invasive tumors.However,the role of GNAS mutations in the invasiveness of GHPAs is unclear.GNAS mutations were detected in GHPAs using a standard polymerase chain reaction(PCR)sequencing procedure.The expression of mutation-associated maternally expressed gene 3(MEG3)was evaluated with RT-qPCR.MEG3 was manipulated in GH3 cells using a lentiviral expression system.Cell invasion ability was measured using a Transwell assay,and epithelial–mesenchymal transition(EMT)-associated proteins were quantified by immunofluorescence and western blotting.Finally,a tumor cell xenograft mouse model was used to verify the effect of MEG3 on tumor growth and invasiveness.The invasiveness of GHPAs was significantly decreased in mice with mutated GNAS compared with that in mice with wild-type GNAS.Consistently,the invasiveness of mutant GNASexpressing GH3 cells decreased.MEG3 is uniquely expressed at high levels in GHPAs harboring mutated GNAS.Accordingly,MEG3 upregulation inhibited tumor cell invasion,and conversely,MEG3 downregulation increased tumor cell invasion.Mechanistically,GNAS mutations inhibit EMT in GHPAs.MEG3 in mutated GNAS cells prevented cell invasion through the inactivation of the Wnt/β-catenin signaling pathway,which was further validated in vivo.Our data suggest that GNAS mutations may suppress cell invasion in GHPAs by regulating EMT through the activation of the MEG3/Wnt/β-catenin signaling pathway.

A powder-scale multiphysics framework for powder bed fusion of fiber-reinforced polymer composites

Additive manufacturing of fiber-reinforced polymer composites has garnered great interest due to its potential in fabricating functional products with lightweight characteristics and unique material properties.However,the major concern in polymer composites remains the presence of pore defects,as a thorough understanding of pore formation is insufficient.In this study,a powder-scale multiphysics framework has been developed to simulate the printing process of fiber-reinforced polymer composites in powder bed fusion additive manufacturing.This numerical framework involves various multiphysics phenomena such as particle flow dynamics of fiber-reinforced polymer composite powder,infrared laser–particle interaction,heat transfer,and multiphase fluid flow dynamics.The melt depths of one-layer glass fiber–reinforced polyamide 12 composite parts fabricated by selective laser sintering are measured to validate modelling predictions.The numerical framework is employed to conduct an in-depth investigation of pore formation mechanisms within printed composites.Our simulation results suggest that an increasing fiber weight fraction would lead to a lower densification rate,larger porosity,and lower pore sphericity in the composites.

New prospecting progress using information and big data of coal and oil exploration holes on sandstone-type uranium deposit in North China

1.Objective A series of Mesozoic-Cenozoic continental sedimentary basins exist in North China,coexisting with coal,oil/gas,and salt resources.Many previous drilling projects have been conducted within these basins to explore coal,petroleum,and mineral resources,however,these data have not been integrated due to different industries owners.In order to efficiently explore the large-sized,easily extracted,and environmentally friendly,sandstone-type uranium deposits,previous coal and oil exploration drilling-hole data are systematically collected, processed,and analyzed to improve the sandstone-type uranium prospecting exploitation.At the same time,we also discussed the uranium source,ore-forming process and model for the sandstone-type uranium deposits.

TIR/BB-loop mimetic AS-1 protects vascular endothelial cells from injury induced by hypoxia/reoxygenation

Morphological and functional abnormalities of vascular endothelial cells(VECs) are risk factors of ischemiareperfusion in skin flaps.Signaling pathway mediated by interleukin-1 receptor(IL-1 R) is essential to hypoxia/reoxygenation(H/R) injury of VECs.While the TIR/BB-loop mimetic(AS-1) disrupts the interaction between IL-1 R and myeloid differentiation primary-response protein 88(MyD88),its role in the VECs dysfunction under H/R is unclear.In this study,we first showed that there was an infiltration of inflammatory cells and the apoptosis of VECs by using a skin flap section from patients who received flap transplantation.We then showed that the H/R treatment induced apoptosis and loss of cell migration of endothelial cell line H926 were attenuated by AS-1.Furthermore,our data suggested that AS-1 inhibits the interaction between IL-1 R and MyD88,and subsequent phosphorylation of IκB and p38 pathway,as well as the nuclear localization of NF-κB subunit p65/p50.Thus,this study indicated that the protective role of AS-1 in H/R induced cellular injury may be due to the AS-1 mediated down-regulation of IL-1 R signaling pathway.

Yogurt-derived Lactobacillus plantarum Q16 alleviated high-fat diet-induced non-alcoholic fatty liver disease in mice

Accumulating evidence revealed that some probiotics regulated lipid metabolism and alleviated diet-induced non-alcoholic fatty liver disease(NAFLD).This study mainly explored whether yogurt-derived Lactobacillus plantarum Q16 modulated lipid and energy metabolism,and suppressed microbial dysbiosis in high-fat diet(HFD)-fed mice.Results showed that oral administration of L.plantarum Q16 improved serum and hepatic lipid profile.Protein analysis showed that L.plantarum Q16 could reduce hepatic lipid content by reducing the expression of FAS,ACC,SCD-1,Srebp-lc and ATGL,but increasing expression levels of CPT-1α,PPAR-αand ATGL.Meanwhile,L.plantarum Q16 also improved hepatic energy metabolism by regulating FGF21/adiponectin/AMPKα/PGC-1αsignaling pathway.Metagenomic analysis also discovered that L.plantarum Q16 increased species diversity and richness of intestinal microbiota,promoted proliferation of beneficial commensals and suppressed the growth of endotoxin-producing microorganisms in the colon of HFD-fed mice.Overall,L.plantarum Q16 protected against HFD-induced NAFLD by improving hepatic profile and regulating colonic microbiota composition.

英国幼儿学校体系创立者怀尔德斯平的理论与实践述评

梳理19世纪有关英国教育的著作、督学报告及媒体报纸等资料可以发现,塞缪尔·怀尔德斯平是促进英国幼儿学校发展的先驱,他创造了一种不同于罗伯特·欧文的幼儿教育理论与幼儿学校体系,并使之成为全国教育体系的组成部分。怀尔德斯平在理论上基于幼儿独特的学习方式阐述了幼儿教育的原则,完整地论述了幼儿学校的诸要素;在实践上打造了幼儿学校模板,开发了操场的教育价值,设计了阶梯教室,建立了全国性的幼儿学校网络,为英国幼儿学校事业作出了不可磨灭的贡献。

中国南海永兴岛跳小蜂科名录及一新种(膜翅目:小蜂总科)

为全面调查中国海南省三沙市永兴岛的跳小蜂科物种多样性,于2017~2020年期间采集了永兴岛的跳小蜂。经鉴定,共发现跳小蜂10种,包含1新种:Ooencyrtus yongxingensis Zu&Xue sp.nov.及2中国新记录种:Adelencyrtus mangiphila(Risbec,1952),Metaphycus agarwali Hayat and Subba Rao,1981。文中还提供了永兴岛跳小蜂科名录。

Propulsive performance of two-and three-dimensional flapping flexible plates

The propulsive performance of two- and three-dimensional （2D and 3D） flapping flexible plates in a fluid at rest is investigated by a finite element method for the plate motion and an immersed boundary-lattice Boltzmann method for the fluid flow. We consider a model that as the leading-edge of the plate takes a vertical oscillation, the entire plate moves freely due to the fluid-structure interaction. The effects of flexibility on the dynamics of the 2D and 3D flapping plates are investigated. It is found that a suitable flexibility is benefit for improving the propulsive performance. The results obtained in this study provide physical insight into the understanding of the dynamics of the flapping-based locomotion.

DNA sequencing by synthesis with degenerate primers

The degenerate primer-based sequencing was developed by a synthesis method （DP-SBS） for high-throughput DNA sequencing, in which a set of degenerate primers are hybridized on the arrayed DNA templates and extended by DNA polymerase on microarrays. In this method, a different set of degenerate primers containing a given number （n） of degenerate nucleotides at the 3＇-ends were annealed to the sequenced templates that were immobilized on the solid surface. The nucleotides （n＋1） on the template sequences were determined by detecting the incorporation of fluorescent labeled nucleotides. The fluorescent labeled nucleotide was incorporated into the primer in a base-specific manner after the enzymatic primer extension reactions and nine-base length were read out accurately. The main advantage of the DP-SBS is that the method only uses very conventional biochemical reagents and avoids the complicated special chemical reagents for removing the labeled nucleotides and reactivating the primer for further extension. From the present study, it is found that the DP-SBS method is reliable, simple, and cost-effective for laboratory-sequencing a large amount of short DNA fragments.

Excellent thermoelectric performance predicted in Sb_(2)Te with natural superlattice structure

Using first-principles calculations combined with the Boltzmann transport theory,we explore the thermoelectric properties of natural superlattice(SL)structure Sb_(2)Te.The results show that n-type Sb_(2)Te possesses larger Seebeck coefficient of 249.59(318.87)μV/K than p-type Sb_(2)Te of 219.85(210.38)μV/K and low lattice thermal conductivity of 1.25(0.21)W/mK along the in-plane(out-of-plane)direction at 300 K.The excellent electron transport performance is mainly attributed to steeper density of state around the bottom of conduction band.The ultralow lattice thermal conductivity of Sb_(2)Te is mainly caused by low phonon group velocity and strong anharmonicity.Further analysis shows that the decrease of group velocity comes from flatter dispersion curves which are contributed by the Brillouin-zone folding.The strong anharmonicity is mainly due to the presence of lone-pair electrons in Sb_(2)Te.Combining such a high Seebeck coefficient with the low lattice thermal conductivity,maximum n-type thermoelectric figure of merit(ZT)of 1.46 and 1.38 could be achieved along the in-plane and out-of-plane directions at room temperature,which is higher than the reported values of Sb_(2)Te_(3).The findings presented here provide insight into the transport property of Sb_(2)Te and highlight potential applications of thermoelectric materials at room temperature.

Adaptive genetic algorithm-based design of gamma-graphyne nanoribbon incorporating diamond-shaped segment with high thermoelectric conversion efficiency

The gamma-graphyne nanoribbons(γ-GYNRs) incorporating diamond-shaped segment(DSSs) with excellent thermoelectric properties are systematically investigated by combining nonequilibrium Green’s functions with adaptive genetic algorithm. Our calculations show that the adaptive genetic algorithm is efficient and accurate in the process of identifying structures with excellent thermoelectric performance. In multiple rounds, an average of 476 candidates(only 2.88% of all16512 candidate structures) are calculated to obtain the structures with extremely high thermoelectric conversion efficiency.The room temperature thermoelectric figure of merit(ZT) of the optimal γ-GYNR incorporating DSSs is 1.622, which is about 5.4 times higher than that of pristine γ-GYNR(length 23.693 nm and width 2.660 nm). The significant improvement of thermoelectric performance of the optimal γ-GYNR is mainly attributed to the maximum balance of inhibition of thermal conductance(proactive effect) and reduction of thermal power factor(side effect). Moreover, through exploration of the main variables affecting the genetic algorithm, it is revealed that the efficiency of the genetic algorithm can be improved by optimizing the initial population gene pool, selecting a higher individual retention rate and a lower mutation rate. The results presented in this paper validate the effectiveness of genetic algorithm in accelerating the exploration of γ-GYNRs with high thermoelectric conversion efficiency, and could provide a new development solution for carbon-based thermoelectric materials.

Thermoelectric properties of orthorhombic silicon allotrope Si(oP32)from first-principles calculations

The diamond-like cubic silicon(d-Si)is widely used in modern electronics and solar cell industries.However,it is not an optimal candidate for thermoelectric application due to its high lattice thermal conductivity.Si(oP32)is a recently predicted orthorhombic silicon allotrope,whose total energy is close to that of d-Si.Using first-principles calculations and Boltzmann transport theory,we systematically investigate the thermoelectric properties of Si(oP32).The lower phonon thermal conductivity and higher power factor are obtained in Si(oP32)than those in diamond silicon.The low phonon thermal conductivity(33.77 W/mK at 300 K)is mainly due to the reduction of the phonon group velocity and enhancement of phonon-phonon scattering(including scattering phase space and strength).Meanwhile,the results also show that the thermoelectric performance along the zz lattice direction is better than that along the xx and yy lattice directions,and the figure of merit(700 K)along the zz lattice direction could approach to 2.45 and 1.75 for p-type and n-type Si(oP32),respectively.The values are much higher than those of d-Si(about 0.06))and Si24(0.6),indicating that the Si(oP32)is a promising candidate for thermoelectric applications.Our theoretical studies shed light on the thermoelectric properties of Si(oP32)and could stimulate further experimental studies.

A Comparative Simulation:Difference between Chemical Grafting and Physical Doping of Cellulose by Using Polysilsesquioxane

In order to study the effect of different modification methods on polysilsesquioxane(POSS)modified cellulose,a molecular dynamics method was used to establish a pure cellulose model and a series of modified models modified by polysilsesquioxane in different ways.And their thermodynamic properties were calculated.The results showed that the performance of cellulose models was better than that of unmodified model,and the modified effect was the best when two cellulose chains were grafted onto polysilsesquioxane by chemical bond(M2 model).Compared with pure cellulose model,the cohesive energy density and solubility parameters of M2 model are increased by 9%,and the values of tensile modulus,bulk modulus,shear modulus and Cauchy pressure increased by 38.6%,29.5%,41.1% and 29.5%,respectively.In addition,the free volume fraction and mean square displacement of each model were calculated and analyzed in this work.Compared with the pure cellulose model,the molecular chain entanglement of cellulose was increased due to the existence of the chemical bonds in the M2 model,which made the cellulose molecular chains occupy more free volume,so that the system had a smaller free volume fraction,inhibited the chain movement of cellulose chains,and thus improved the thermal stability of cellulose.

Calculation of the Nonlinear Susceptibility in van der Waals Crystals

The development of theoretical models for crystals has led to the evolution of computational methods with which much more thorough investigations than previously possible can be done, including studies of the nonlinear optical properties. There has recently been a rise in interest in 2-dimensional materials;unfortunately, measurements of the nonlinear susceptibility of these materials in the wavelength range of the order of hundreds of nanometers by traditional methods are difficult. Studies of second-harmonic generation (SHG) from the transition-metal dichalcogenides (TMDCs), MoS2 and MoSe2, have been reported;however, SHG from other typical van der Waals crystals such as GaSe and other transition metal monochalcogenides (TMMCs) has rarely been studied under the same conditions. In this study, the 211 (i = 2, j = 1, k = 1) elements in the susceptibility matrices of GaSe, InSe, MoS2 and WS2 were calculated and compared. A tendency for the SHG intensity to weaken as the wavelength increases from 500 nm to 1000 nm was observed for GaSe and InSe, and, apart from some periodic fluctuations, no clear increase could be seen for these two materials in the SHG response curve in the near infrared. By comparison, MoS2 and WS2 have obvious peaks in both the visible and infrared bands. Calculations of the SHG response show peaks at around 500 nm (for GaSe), 570 (for InSe), 660 nm, 980 nm (for MoS2) and 580 nm, 920 nm (for WS2). Moreover, similarities between the SHG curves for GaSe and InSe and for MoS2 and WS2 were revealed, which may be due to the similarities found for these two groups of crystals.

Application of Computer Vision Technology in Intelligent Transportation

With the social development and the continuous improvement of scientific and technological level,the people's living standards continue to improve,and the demand for intelligent technology is also increasing.In recent years,with the increase of the number of cars and the frequent occurrence of traffic accidents,the problem of traffic safety has attracted the attention of all sectors of society,and computer vision technology has been gradually appliedto intelligent transportation.This paper analyzes the application of computer vision technology in detail,so as to provide reference for the development of intelligent transportation in our country.

Application Analysis of Computer Technology in Composite Mapping

In the process of architectural composite drawing,due to its cumbersome process,the work efficiency of manual drawing alone is low,and the accuracy is difficult to ensure.By using computer technology to carry out composite drawing,we can not only improve the drawing accuracy,but also save a lot of manpower and material resources.At present,the commonly used computer composite drawing technologies include AutoCAD,3ds max,BIM,etc.This paper analyzes these technology types in detail to provide reference for architectural composite drawing.

CShaperApp:Segmenting and analyzing cellular morphologies of the developing Caenorhabditis elegans embryo

Caenorhabditis elegans has been widely used as a model organism in developmental biology due to its invariant development.In this study,we developed a desktop software CShaperApp to segment fluorescence-labeled images of cell membranes and analyze cellular morphologies interactively during C.elegans embryogenesis.Based on the previously proposed framework CShaper,CShaperApp empowers biologists to automatically and efficiently extract quantitative cellular morphological data with either an existing deep learning model or a fine-tuned one adapted to their in-house dataset.Experimental results show that it takes about 30 min to process a three-dimensional time-lapse(4D)dataset,which consists of 150 image stacks at a~1.5-min interval and covers C.elegans embryogenesis from the 4-cell to 350-cell stages.The robustness of CShaperApp is also validated with the datasets from different laboratories.Furthermore,modularized implementation increases the flexibility in multi-task applications and promotes its flexibility for future enhancements.As cell morphology over development has emerged as a focus of interest in developmental biology,CShaperApp is anticipated to pave the way for those studies by accelerating the high-throughput generation of systems-level quantitative data collection.The software can be freely downloaded from the website of Github(cao13jf/CShaperApp)and is executable on Windows,macOS,and Linux operating systems.

Serum metabolic profiling implicates mTOR activation and insulin resistance in the development of pulmonary hypertension in a rat model of pressure overload-induced heart failure

Pulmonary hypertension(PH)due to left heart failure(HF)accounts for approximately half of PH cases worldwide.It has been demonstrated that PH is a frequent complication of HF but is difficult to recognize in its early stage because it is characterized by nonspecific symptoms including shortness of breath and decreased tolerance of activity.Moreover,nearly all multicentric clinical trials targeting pulmonary circulation in PH-HF have reported negative results.1 Thus,there are no effective methods for diagnosing early PH,and the current treatment of PH-HF is insufficient.

Prediction of dissolved gas content in transformer oil based on multi-information fusion

In order to accurately predict the content and variation trend of dissolved gas in trans-former oil and guide the condition maintenance of power transformers,a combined prediction model based on multi-information fusion is proposed and its effectiveness is analysed.First of all,based on the possibility of pathological and missing historical sample data,a detection and filling method based on variable weight combination samples is established.Second,the authors propose two models.Aiming at the non-linear and non-stationary characteristics of gas content,a univariate decomposition prediction mode HBA-VMD-TCN which based on the Honey Badger algorithm,variational mode decomposition and time convolutional network(TCN)is established.Then the multi-variate Informer prediction model is established for gas content affected by multiple variables.Third,the cross-entropy theory is used to determine the weight coefficients of the two models,and the multi-information fusion combined prediction model is formed.Finally,on the basis of the above,a method to determine the time step and the position information of the transition point adaptively in the process of prediction is proposed to further improve the prediction accuracy.The results show that,through a series of simulation experiments of model comparison and transformer anomaly prediction,the accuracy and effectiveness of the combined prediction model are verified.