液相流路控制与微流控核酸扩增芯片偶联系统的研制

随着载人航天和空间探测技术的进步,空间站特殊环境导致常规仪器无法直接在空间站内正常运行,使得改进和开发适用于空间站的生物分析检测设备变得非常重要。其中核酸作为一个重要的生物大分子,在生物科学研究中对它的分析是必不可少的。本研究针对核酸扩增设备在航天中的应用提出了一种液相流路偶联微流控核酸扩增芯片系统来解决微重力环境下核酸检测过程中对于液体处理的问题,实验结果表明液体混合良好,密封性良好,能满足微重力条件的液体传输。这一系统为基于微流控芯片的空间核酸分析设备的开发提供思路。

Impedance matching for repetitive high voltage all-solid-state Marx generator and excimer DBD UV sources

The purpose of impedance matching for a Marx generator and DBD lamp is to limit the output current of the Marx generator,provide a large discharge current at ignition,and obtain fast voltage rising/falling edges and large overshoot.In this paper,different impedance matching circuits（series inductor,parallel capacitor,and series inductor combined with parallel capacitor） are analyzed.It demonstrates that a series inductor could limit the Marx current.However,the discharge current is also limited.A parallel capacitor could provide a large discharge current,but the Marx current is also enlarged.A series inductor combined with a parallel capacitor takes full advantage of the inductor and capacitor,and avoids their shortcomings.Therefore,it is a good solution.Experimental results match the theoretical analysis well and show that both the series inductor and parallel capacitor improve the performance of the system.However,the series inductor combined with the parallel capacitor has the best performance.Compared with driving the DBD lamp with a Marx generator direcdy,an increase of 97.3%in radiant power and an increase of 59.3%in system efficiency are achieved using this matching circuit.

Characterization of an Electromagnetic Vibration Isolator

A novel vibration isolator is constructed by connecting a mechanical spring in parallel with a magnetic spring in order to achieve the property of high-static-low-dynamic stiffness (HSLDS). The HSLDS property of the isolator can be tuned off-line or on-line. This study focuses on the characterization of the isolator using a finite element based package. Firstly using the single physics solver, the stiffness behaviours of the mechanical and magnetic springs are determined, respectively. Then using the weakly coupled multi-physics method, the stiffness behaviours of the passive isolator and the semi-active isolator are investigated, respectively. With the found stiffness models, a nonlinear differential equation governing the dynamics of the isolator is solved using the time-dependent solver. The displacement transmissibility ratios of the isolator are obtained. The study confirms that the isolation region of the isolator can be widened through off-line or on-line tuning.

Study of tetracycline removal and saturated resin regenerated by dielectric barrier discharge plasma

The wastewater produced by the large-scale usage of antibiotics worldwide was more harmful to the ecological environment and human health.In the research,the coupling technology of‘adsorption-plasma regeneration'was taken to treat tetracycline in aqueous solution.The pollutants were adsorbed by the resins firstly and then regenerated ectopically by dielectric barrier discharge plasma.The discharge parameters,such as discharge voltage and frequency were researched to achieve the optimal regeneration efficiency and energy efficiency.Meanwhile,the analyses of the surface functional groups and microstructure were also investigated.After the five‘adsorption-regeneration'processes,the results showed that the optimal discharge parameters of voltage and frequency were 20 k V and 1 k Hz,respectively.The regeneration efficiency and energy efficiency were above 80%and 115 g k W^(-1)·h^(-1),respectively.The tetracycline adsorption by virgin resin and regenerated resin nearly followed pseudo-second order kinetics,and there was no fatal damage to the surface characteristics and physicochemical properties of the resins through the multiple plasma regeneration processes.Finally,according to the intra-particle diffusion model and the degradation products detected by GC-MS,the adsorption and degradation mechanisms of tetracycline were deduced.

Influence of electrical parameters on H2O2 generation in DBD non-thermal reactor with water mist

A dielectric barrier discharge（DBD） reactor is introduced to generate H2O2 by non-thermal plasma with a mixture of oxygen and water mist produced by an ultrasonic atomizer.The results of our experiment show that the energy yield and concentration of the generated H2O2 in the pulsed discharge are much higher than that in AC discharge,due to its high energy efficiency and low heating effect.Micron-sized liquid droplets produced by an ultrasonic atomizer in water mist have large specific surface area,which greatly reduces mass transfer resistance between hydroxyl radicals and water liquids,leading to higher energy yield and H2O2 concentration than in our previous research.The influence of applied voltage,discharge frequency,and environmental temperature on the generated H2O2 is discussed in detail from the viewpoint of the DBD mechanism.The H2O2 concentration of 30 mg l^-1,with the energy yield of 2 gkW^-1h^-1 is obtained by pulsed discharge in our research.

The Role of KDM2A and H3K36me2 Demethylation in Modulating MAPK Signaling During Neurodevelopment

Intellectual disability(ID)is a condition characterized by cognitive impairment and difficulties in adaptive functioning.In our research,we identified two de novo mutations(c.955C>T and c.732C>A)at the KDM2A locus in individuals with varying degrees of ID.In addition,by using the Gene4Denovo database,we discovered five additional cases of de novo mutations in KDM2A.The mutations we identified significantly decreased the expression of the KDM2A protein.To investigate the role of KDM2A in neural development,we used both 2D neural stem cell models and 3D cerebral organoids.Our findings demonstrated that the reduced expression of KDM2A impairs the proliferation of neural progenitor cells(NPCs),increases apoptosis,induces premature neuronal differentiation,and affects synapse maturation.Through ChIP-Seq analysis,we found that KDM2A exhibited binding to the transcription start site regions of genes involved in neurogenesis.In addition,the knockdown of KDM2A hindered H3K36me2 binding to the downstream regulatory elements of genes.By integrating ChIP-Seq and RNA-Seq data,we made a significant discovery of the core genes'remarkable enrichment in the MAPK signaling pathway.Importantly,this enrichment was specifically linked to the p38 MAPK pathway.Furthermore,disease enrichment analysis linked the differentially-expressed genes identified from RNA-Seq of NPCs and cerebral organoids to neurodevelopmental disorders such as ID,autism spectrum disorder,and schizophrenia.Overall,our findings suggest that KDM2A plays a crucial role in regulating the H3K36me2 modification of downstream genes,thereby modulating the MAPK signaling pathway and potentially impacting early brain development.

Non-thermal plasma treatment of Radix aconiti wastewater generated by traditional Chinese medicine processing

The wastewater effluent from Radix aconiti processing, an important step in the production processes of traditional Chinese medicine（TCM）, is a type of toxic wastewater and difficult to treat. Plasma oxidation methods have emerged as feasible techniques for effective decomposition of toxic organic pollutants. This study examined the performance of a plasma reactor operated in a dielectric barrier discharge（DBD） to degrade the effluent from R. aconiti processing. The effects of treatment time, discharge voltage, initial pH value and the feeding gas for the reactor on the degradation of this TCM wastewater were investigated. A bacterium bioluminescence assay was adopted in this study to test the toxicity of the TCM wastewater after non-thermal plasma treatment. The degradation ratio of the main toxic component was 87.77% after 60 min treatment with oxygen used as feed gas and it was 99.59% when the initial p H value was 8.0. High discharge voltage and alkaline solution environment were beneficial for improving the degradation ratio. The treatment process was found to be capable of reducing the toxicity of the wastewater to a low level or even render it non-toxic. These experimental results suggested that the DBD plasma method may be a competitive technology for primary decomposition of biologically undegradable toxic organic pollutants in TCM wastewater.