PPAR-γactivation promotes xenogenic bioroot regeneration by attenuating the xenograft induced-oxidative stress

Xenogenic organ transplantation has been considered the most promising strategy in providing possible substitutes with the physiological function of the failing organs as well as solving the problem of insufficient donor sources.However,the xenograft,suffered from immune rejection and ischemia-reperfusion injury(IRI),causes massive reactive oxygen species(ROS)expression and the subsequent cell apoptosis,leading to the xenograft failure.Our previous study found a positive role of PPAR-γ in antiinflammation through its immunomodulation effects,which inspires us to apply PPAR-γ agonist rosiglitazone(RSG)to address survival issue of xenograft with the potential to eliminate the excessive ROS.In this study,xenogenic bioroot was constructed by wrapping the dental follicle cells(DFC)with porcine extracellular matrix(p ECM).The hydrogen peroxide(H_(2)O_(2))-induced DFC was pretreated with RSG to observe its protection on the damaged biological function.Immunoflourescence staining and transmission electron microscope were used to detect the intracellular ROS level.SD rat orthotopic transplantation model and superoxide dismutase 1(SOD1)knockout mice subcutaneous transplantation model were applied to explore the regenerative outcome of the xenograft.It showed that RSG pretreatment significantly reduced the adverse effects of H2O2on DFC with decreased intracellular ROS expression and alleviated mitochondrial damage.In vivo results confirmed RSG administration substantially enhanced the host’s antioxidant capacity with reduced osteoclasts formation and increased periodontal ligament-like tissue regeneration efficiency,maximumly maintaining the xenograft function.We considered that RSG preconditioning could preserve the biological properties of the transplanted stem cells under oxidative stress(OS)microenvironment and promote organ regeneration by attenuating the inflammatory reaction and OS injury.

Large-scale CO(J=1-0)Observations toward the M120.1+3.0 Molecular Cloud:A Filament with a Chain of Starburst Clusters

We present large-scale(2°×2°)observations toward the molecular cloud M120.1+3.0,using ^(12)CO,^(13)CO and C^(18)O(J=1-0)data from the Purple Mountain Observatory 13.7 m millimeter telescope.The distance of the cloud is measured to be~1.1 kpc.Using the ^(13)CO data,we identify a main filament F1 and two sub-filaments F2 and F3 in the cloud,which together show a"hub-filament"structure.Filaments F1 and F2 are thermally supercritical.Furthermore,F1 displays clear localized systematic motions in the ^(13)CO position-velocity diagram,which could be explained by accretion along the filament.The mean estimated accretion rate is~132M_(⊙)Myr^(-1).Approximately 150 ^(13)CO clumps are identified in the cloud,of which 39 are gravitationally bound.Most of these virialized clumps are well distributed along the supercritical filaments F1 and F2.Based on the complementary infrared and optical data,we identify~186 young stellar objects in the observed area and extract five clusters within the dense ridge of F1.The calculated star formation rate(SFR)surface densities(∑_(SFR))in the clusters range from 1.4 to 2.5 M_(⊙)Myr^(-1)pc^(-2),with a mean value of~2.0M_(⊙)Myr^(-1)pc^(-2).We therefore regard them as mini-starburst cluster candidates.The comparison between ∑_(SFR) and column density N_(gas) along the skeleton of F1 suggests that star formation is closely related to the dense gas in the cloud.Along the main filament F1,five bipolar outflows are also found.All these results indicate intense star-forming activities in the M120.1+3.0 molecular cloud.

白细胞介素-1α信号通路在牙萌出中的研究

牙萌出是发育中的牙齿穿过牙槽骨和口腔黏膜到达功能位置的复杂生理过程,其间牙槽骨、牙囊、破骨细胞、成骨细胞及多种细胞因子等共同参与该过程。白细胞介素(IL)-1α是具有特殊生理意义的双重功能细胞因子。本文就IL-1α信号通路在牙萌出中的研究进行综述。

The MOOC/SPOC Based"1+M+N"Multi-University Collaborative Teaching and Learning Mode:Practice and Experience

Since 2012, the MOOCs, the massive open online courses, have brought big influences on the higher education in the world. How to use MOOCs to help universities rather than bother them to improve their education level and quality becomes an important issue. In China, many universities have explored the new modes and approaches for MOOC/SPOC-based teaching and learning. Especially, the China MOOC Association on Computing Education(CMOOC association), established in 2014, has done a set of successful practice and achieved fruitful experiences on MOOC courses development and computer education reform. Based on the practical experiences, a MOOC/SPOC based "1+M+N" multi-university collaborative teaching and learning mode is presented, which is adapted to the real situation of Chinese university education. In the paper, the practices and experiences of CMOOC association are introduced, the MOOC/SPOC based "1+M+N" multi-university collaborative teaching and learning mode and its approaches are described. Finally, the suggestions for MOOCs development and applications are also presented.

Messages from CEISEE 2022 Committee

With rapid development of the new generation information technology and its wide applications,human society is coming into the new phase of digital world supported by metaverse.Software engineering education will also be influenced and promoted by metaverse.The theme of 2022 China-Europe International Symposium on Software Engineering Education,CEISEE 2022,is defined as“How the metaverse is shaping the future of education”.

MOOC construction of major core course and reform of Hybrid Teaching Mode Taking "principle of embedded system" as an example

The development of MOOC directly promotes the reform of physical classroom teaching,and leads to the reform of teaching mode and teaching method in the direction of improving teachers’teaching quality and students’learning effect and innovation ability.In order to meet the needs of MOOC teaching reform,based on the MOOC built by ourselves and running on the MOOC platform,this paper puts forward the hybrid teaching mode reform of the core courses of an computer specialty,which combines online and offline in depth.Sort out the knowledge system of an embedded system,build MOOC and put it online on domestic well-known MOOC platform,compile supporting teaching materials,and form an organic combination of online and offline teaching resources;proposing a hybrid teaching mode of online and offline combination,which focuses on interactive classroom teaching reform.On the basis of organizing students to carry out online autonomous learning,online and offline entity classroom carries out interactive classroom teaching reform;Using intelligent teaching tools to promote students to use mobile phones to participate in classroom learning,improve the universality of interactive teaching,carry out flipped classroom teaching,and improve the depth of interactive teaching.Based on the independent construction of MOOC,the hybrid teaching is carried out,which improves the pertinence of online teaching organization.The information-based teaching and flipped classroom teaching in the physical classroom improve the students’ability to solve problems,and lay a solid foundation for the improvement of teaching quality and learning effect.

盐分介导下芦苇对不同邻体植物的表型可塑性响应

随着滨海湿地生态系统盐胁迫增加,群落中的植物同时受到盐胁迫和植物相互作用的影响。非生物因素干扰植物之间竞争和促进效应的稳定,使植物产生复杂的表型可塑性响应。探讨不同的邻体物种及对性状可塑性的影响将会扩展胁迫梯度假说,深入理解盐沼湿地的物种分布特征。本研究开展温室控制实验,探究盐胁迫下(0和10 g/L)芦苇(Phragmites australis)对3种功能类型7种邻体植物(同种植物、禾草类植物和杂草类植物)的表型可塑性响应。实验测量了株高、基径、密度、叶厚度、比叶面积、总生物量和各部分生物量等性状,计算了邻体效应指数(基于生物量)和相对表型可塑性指数。结果表明,盐分显著降低了芦苇的生物量、株高、密度和基径。邻体植物的功能类型显著影响芦苇的生长性状。盐分为0 g/L时,禾草类植物对芦苇形成负的竞争效应,但在10 g/L盐分下,这种负效应转变为正的促进作用。芦苇的生长性状对盐分和竞争具有可塑性反应,如增加地下生物量以获得更多的水分和资源,可塑性指数在盐分条件下比竞争条件下更高。总之,植物-植物相互作用对胁迫的响应随植物功能类型和性状可塑性而异。

Directly accessing octave-spanning dissipative Kerr soliton frequency combs in an AlN microresonator

Self-referenced dissipative Kerr solitons (DKSs) based on optical microresonators offer prominent characteristics allowing for various applications from precision measurement to astronomical spectrometer calibration. To date,direct octave-spanning DKS generation has been achieved only in ultrahigh-Q silicon nitride microresonators under optimized laser tuning speed or bi-directional tuning. Here we propose a simple method to easily access the octave-spanning DKS in an aluminum nitride (AlN) microresonator. In the design,two modes that belong to different families but with the same polarization are nearly degenerate and act as a pump and an auxiliary resonance,respectively. The presence of the auxiliary resonance can balance the thermal dragging effect,crucially simplifying the DKS generation with a single pump and leading to an enhanced soliton access window. We experimentally demonstrate the long-lived DKS operation with a record single-soliton step (10.4 GHz or83 pm) and an octave-spanning bandwidth (1100–2300 nm) through adiabatic pump tuning. Our scheme also allows for direct creation of the DKS state with high probability and without elaborate wavelength or power schemes being required to stabilize the soliton behavior.

Effects of regulated deficit irrigation on soil salinity,physiological processes and fruit quality of gray jujube under desert conditions

Regulated deficit irrigation(RDI)was applied to gray jujube trees in an oasis region,to determine the effects of this irrigation system on soil salinity,gray jujube physiological processes,fruit yield,and fruit quality.Treatments consisted of severe,moderate and low deficit irrigation(irrigated with 85%,70%and 55%of CK,respectively)at the flowering stage to fruit set stage.During the other growth stages,all treatments were irrigated with 80%of pan evaporation,which was the same as that in control.The results indicated that soil salinity was enhanced during the periods of water stress,but the high value of soil salinity declined by 3.48%-37.27%,at each depth,after irrigation was resumed.RDI caused a decline in the photosynthetic rate,transpiration rate,and stomatal conductance,but enhanced the water use efficiency of the leaves.However,the leaf photosynthetic rate was effectively enhanced after the recovery of irrigation,especially in the moderate deficit irrigation treatment,which exceeded the control.This led to an improved fruit yield,which was 9.57%higher than that of the control.The deficit treatments caused a significant increase in the soluble solid content,soluble sugar content,single fruit weight and sugar/acid ratio.Enhanced vitamin C content,resulting from deficit treatments,has also been observed in the gray jujube.Therefore,this research shows that RDI provides some benefits in the production of gray jujube trees in desert conditions.

Narrow-linewidth thermally tuned multi-channel interference widely tunable semiconductor laser with thermal tuning power below 50 mW

A thermally tuned multi-channel interference widely tunable semiconductor laser is designed and demonstrated,for the first time to our knowledge,that realizes a tuning range of more than 45 nm,side-mode suppression ratios up to 56 d B,and Lorentzian linewidth below 160 k Hz.Al Ga In As multiple quantum wells(MQWs)were used to reduce linewidth,which have a lower linewidth enhancement factor compared with In Ga As P MQWs.To decrease the power consumption of micro-heaters,air gaps were fabricated below the arm phase sections.For a 75μm long suspended thermal tuning waveguide,about 6.3 m W micro-heater tuning power is needed for a 2πround-trip phase change.Total micro-heater tuning power required is less than 50 m W across the whole tuning range,which is lower than that of the reported thermally tuned tunable semiconductor lasers.

Recent development of nanomaterials for carbon dioxide electroreduction

Electrochemical CO_(2) reduction reaction(CO_(2)RR)to produce value‐added products has received tremendous research attention in recent years.With research efforts across the globe,remarkable advancement has been achieved,including the improvement of selectivity for the reduction products,the realization of efficient reduction beyond two electrons,and the delivery of industrially relevant current densities.In this review,we introduce the recent development of nanomaterials for CO_(2)RR,including the zero‐dimensional graphene quantum dots,two‐dimensional materials such as metal chalcogenides and metal/covalent organic framework,singleatom catalysts,and nanostructured metal catalysts.The engineering of materials into three‐dimensional structure will also be discussed.Finally,we will provide a summary of the catalytic performance and perspectives on future development.

Performance of a zero-inertia model for irrigation with rapidly varied inflow discharges

The zero-inertia model is widely used for simulating surface flow in irrigation systems.This model is accurate when inflow discharge is constant.However,simulation of irrigation systems with rapidly varied inflow discharge is needed due to the development of real time control irrigation technology.Hence,the objective of this study is to validate the zero-inertia model with rapidly varied inflow discharge.For this purpose,twenty-three border irrigation tests at a range of inflow changes on different field slopes and roughness coefficients were conducted.Then,the sensitivity analyses of bed slope,infiltration parameters,and roughness coefficient were examined.The results indicate that the zero-inertia model predictions are in good agreement with field data in both advance/recession times and flow depths.The infiltration parameters were the most sensitive input variable of the zero-inertia model.The input variables have a more considerable impact on the recession phase than the advance phase.

Recruited CD68^(+)CD206^(+)macrophages orchestrate graft immune tolerance to prompt xenogeneic-dentin matrix-based tooth root regeneration

Successful regenerative medicine strategies of xenogeneic extracellular matrix need a synergistic balance among inflammation,fibrosis,and remodeling process.Adaptive macrophage subsets have been identified to modulate inflammation and orchestrate the repair of neighboring parenchymal tissues.This study fabricated PPARγ-primed CD68+CD206+M2 phenotype(M2γ),and firstly verified their anti-inflammatory and tissue-regenerating roles in xenogeneic bioengineered organ regeneration.Our results showed that Th1-type CD3^(+)CD8^(+)T cell response to xenogeneic-dentin matrix-based bioengineered root complex(xeno-complex)was significantly inhibited by M2γmacrophage in vitro.PPARγactivation also timely recruited CD68^(+)CD206^(+)tissue macrophage polarization to xeno-complex in vivo.These subsets alleviated proinflammatory cytokines(TNF-α,IFN-γ)at the inflammation site and decreased CD3^(+)CD8^(+)T lymphocytes in the periphery system.When translated to an orthotopic nonhuman primate model,PPARγ-primed M2 macrophages immunosuppressed IL-1β,IL-6,TNF-α,MMPs to enable xeno-complex to effectively escape immune-mediated rejection and initiate graft-host synergistic integrity.These collective activities promoted the differentiation of odontoblast-like and periodontal-like cells to guide pulp-dentin and cementum-PDLs-bone regeneration and rescued partially injured odontogenesis such as DSPP and periostin expression.Finally,the regenerated root showed structure-biomechanical and functional equivalency to the native tooth.The timely conversion of M1-to-M2 macrophage mainly orchestrated odontogenesis,fibrogenesis,and osteogenesis,which represents a potential modulator for intact parenchymal-stromal tissue regeneration of targeted organs.

Design of a single-mode directly modulated orbital angular momentum laser

We propose a design of single-mode orbital angular momentum(OAM) beam laser with high direct-modulation bandwidth. It is a microcylinder/microring cavity interacted with two types of second-order gratings: the complex top grating containing the real part and the imaginary part modulations and the side grating. The side grating etched on the periphery of the microcylinder/microring cavity can select a whispering gallery mode with a specific azimuthal mode number, while the complex top grating can scatter the lasing mode with travelling-wave pattern vertically. With the cooperation of the gratings, the laser works with a single mode and emits radially polarized OAM beams. With an asymmetrical pad metal on the top of the cavity, the OAM on-chip laser can firstly be directly modulated with electrical pumping. Due to the small active volume, the laser with low threshold current is predicted to have a high direct modulation bandwidth about 29 GHz with the bias current of ten times the threshold from the simulation. The semiconductor OAM laser can be rather easily realized at different wavelengths such as the O band, C band, and L band.

Platinum monolayers stabilized on dealloyed AuCu core-shell nanoparticles for improved activity and stability on methanol oxidation reaction

Deposition of platinum(Pt)monolayers(PtML)on Au substrate represents a robust strategy to maximally utilize the Pt atoms and meanwhile achieve high catalytic activity towards methanol oxidation reaction for direct methanol fuel cells owing to a substrate-induced tensile strain effect.However,recent studies showed that Pt(ML)on Au substrate are far from perfect smooth monoatomic layer,but actually exhibited three-dimensional nanoclusters.Moreover,the Pt(ML)suffered from severe structural instability and thus activity degradation during long-term electrocatalysis.To regulate the growth of Pt(ML)Au surface and also to improve its structural stability,we exploit dealloyed AuCu core-shell nanoparticles as a new substrate for depositing Pt(ML).By using high-resolution scanning transmission electron microscopy and energy dispersive X-ray elemental mapping combined with electrochemical characte rizations,we reveal that the dealloyed AuCu core-shell nanoparticles can effectively promote the deposition of Pt(ML)closer to a smooth monolayer structure,thus leading to a higher utilization efficiency of Pt and higher intrinsic activity towards methanol oxidation compared to those on pure Au nanoparticles.Moreover,the Pt(ML)deposited on the AuCu core-shell NPs showed substa ntially enhanced stability compared to those on pure Au NPs during long-term electrocatalysis over several hours,during which segregation of Cu to the Au/Pt interface was revealed and suggested to play an important role in stabilizing the Pt(ML)catalysts.

Novel Lightweight and Protective Battery System Based on Mechanical Metamaterials

The challenges facing electric vehicles with respect to driving range and safety make the design of a lightweight and safe battery pack a critical issue.This study proposes a multifunctional structural battery system comprising cylindrical battery cells and a surrounding lightweight lattice metamaterial.The lattice density distribution was optimized via topological optimization to minimize stress on the battery during compression.Surrounding a single 18650 cylindrical battery cell,non-uniform lattices were designed featuring areas of increased density in an X-shaped pattern and then fabricated by additive manufacturing using stainless steel powders.Compression testing of the assembled structural battery system revealed that the stronger lattice units in the X-shaped lattice pattern resisted deformation and helped delay the emergence of a battery short circuit.Specifically,the short circuit of the structural battery based on a variable-density patterned lattice was∼166%later than that with a uniform-density lattice.Finite element simulation results for structural battery systems comprising nine battery cells indicate that superior battery protection is achieved in specially packed batteries via non-uniform lattices with an interconnected network of stronger lattices.The proposed structural battery systems featuring non-uniform lattices will shed light on the next generation of lightweight and impact-resistant electric vehicle designs.

Directly modulated active distributed reflector distributed feedback lasers over wide temperature range operation(-40 to 85℃)

We experimentally demonstrated that the distributed feedback(DFB) lasers with the active distributed reflector achieved a 25.8 Gb/s operation over a wide temperature range of -40 to 85℃. The DFB lasers can achieve additional feedback from an active distributed reflector with accurately controlled phase, and single-mode yields are not related to the position of cleave. The threshold currents of the fabricated laser are 6 mA and 20 mA at -40℃ and 85℃, respectively. The side mode suppression ratio of the fabricated laser is above 50 dB at all temperatures. Transmissions of 25.8 Gb/s after 10 km single-mode fibers with clear eye openings and less than 0.8 dB power penalty over a wide temperature range have been demonstrated as well.

Simulating advance distance in border irrigation systems based on the improved method of characteristics

Improving the simulation accuracy of the advance distance based on the method of characteristics is essential to develop numerical solutions for simulating surface irrigation.Instead of volume balance in the traditional method of characteristics(T-MC),the position of critical flow is determined to simulate the advance distance in the improved method of characteristics(I-MC),which is used in border irrigation systems with rapid variation in inflow discharge in the current research.Specifically,the zones of both subcritical and supercritical flow were firstly distinguished to determine the position of the critical flow point,which was also the upstream boundary of the wetting front region,and then the advance distance was calculated by applying the diffusive wave equation in the wetting front region.The results showed that the I-MC accurately simulated the advance distance with high determination coefficients(0.984-0.998)and low errors(root mean square error of 0.35-1.56 min and coefficient of residual mass of 0.01-0.06),which performed much better than the T-MC.The I-MC provided a suitable and simple numerical simulation tool to improve the establishment of numerical surface irrigation models.

The Fabrication and Characterization of Polarization Insensitive Semiconductor Optical Amplifier

An angled facet strained bulk InGaAs SOA has been designed and fabricated. A device with double-layer antireflection coatings had <2dB polarization sensitivity and <0.5dB gain ripple.