Characteristics of the electromagnetic wave propagation in magnetized plasma sheath and practical method for blackout mitigation

“Magnetic window”is considered as an effective method to solve the communication blackout issue.COMSOL software package based on the finite element method is utilized to simulate the propagation of right-handed circularly polarized wave in the magnetized plasma sheath.We assume a double Gaussian model of electron density and an exponential attenuation model of magnetic field.The propagation characteristics of right-handed circularly polarized wave are analyzed by the observation of the reflected,transmitted and loss coefficient.The numerical results show that the propagation of right-handed circularly polarized wave in the magnetized plasma sheath varies for different incident angles,collision frequencies,non-uniform magnetic fields and non-uniform plasma densities.We notice that reducing the wave frequency can meet the propagation conditions of whistle mode in the weak magnetized plasma sheath.And the transmittance of whistle mode is less affected by the variation of the electron density and the collision frequency.It can be used as a communication window.

过渡期后农村低收入人口和欠发达地区常态化帮扶机制研究

2020年底,我国已完成脱贫攻坚工作,但同时还存在大量农村低收入人口和欠发达地区,他们有可能成为返贫的“高危人群”。在过渡期后仍需巩固拓展脱贫攻坚成果并与乡村振兴有效衔接,通过常态化帮扶机制防止返贫的发生。本文研判了农村低收入群体的规模及面临的困境,分析了其收入较低的原因,并在梳理分析现有帮扶措施及问题的基础上,提出了过渡期后常态化帮扶机制相关建议,包括:实施更加积极的财政政策,提高对农村居民特别是低收入群体的转移支付力度;改革户籍制度和公共服务体系,大力推进农业转移人口市民化;促进农村土地经营权流转,增加农业转移人口财产性收入;针对关键行业和领域加大投资力度,促进农业农村现代化;加强人力资本投资等。

聚(氨酯-脲-酰胺)热塑性弹性体的合成及表征

以双端氨基的尼龙1212预聚物(OPA)为硬段、异氰酸酯封端的聚醚型聚氨酯预聚物(OPU)为软段,通过改变软、硬段的摩尔比制得了不同相对分子质量的聚(氨酯-脲-酰胺)热塑性弹性体(PUUA)。通过傅里叶变换红外光谱(FT-IR)考察了OPU合成过程中-NCO基团与C-O-C醚键的相对强度变化,进而确定了合成OPU的反应时间为60 min。通过核磁氢谱和FT-IR确定了产物结构。凝胶渗透色谱法(GPC)测试结果表明,硬、软段摩尔比在1.2~1.5范围内,产物重均分子量可在(1.82~3.59)×104范围内调控。差示扫描量热分析(DSC)结果表明,随着硬、软段摩尔比由1.2提高至1.5,硬段的熔点由185℃降低至174℃,结晶温度由167℃降低至138℃,但OPU软段的熔点和结晶温度基本不变。PUUA的力学性能测试结果表明,其拉伸强度为28 MPa,断裂伸长率可达417%,缺口冲击未能冲断,是一种性能优异的热塑性弹性体。

The PI3K/Akt/GSK-3β/ROS/eIF2B pathway promotes breast cancer growth and metastasis via suppression of NK cell cytotoxicity and tumor cell susceptibility

Objective: To examine the effect of pSer9-GSK-3β on breast cancer and to determine whether the underlying metabolic and immunological mechanism is associated with ROS/eIF2B and natural killer(NK) cells.Methods: We employed TWS119 to inactivate GSK-3β by phosphorylating Ser9 and explored its effect on breast cancer and NK cells. The expression of GSK-3β, natural killer group 2 member D(NKG2D) ligands, eIF2B was quantified by PCR and Western blot. We measured intracellular reactive oxygen species(ROS) and mitochondrial ROS using DCFH-DA and MitoSOX^(TM) probe,respectively, and conducted quantitative analysis of cellular respiration on 4T1 cells with mitochondrial respiratory chain complex Ⅰ/Ⅲ kits.Results: Our investigation revealed that TWS119 downregulated NKG2D ligands(H60 a and Rae1), suppressed the cytotoxicity of NK cells, and promoted the migration of 4T1 murine breast cancer cells. Nevertheless, LY290042, which attenuates p-GSK-3β formation by inhibiting the PI3K/Akt pathway, reversed these effects. We also found that higher expression of p Ser9-GSK-3β induced higher levels of ROS, and observed that abnormality of mitochondrial respiratory chain complex Ⅰ/Ⅲ function induced the dysfunction of GSK-3β-induced electron transport chain, naturally disturbing the ROS level. In addition, the expression of NOX3 and NOX4 was significantly up-regulated, which affected the generation of ROS and associated with the metastasis of breast cancer. Furthermore, we found that the expression of pSer535-eIF2B promoted the expression of NKG2D ligands(Mult-1 and Rae1) following by expression of pSer9-GSK-3β and generation of ROS.Conclusions: The PI3K/Akt/GSK-3β/ROS/eIF2B pathway could regulate NK cell activity and sensitivity of tumor cells to NK cells,which resulted in breast cancer growth and lung metastasis. Thus, GSK-3β is a promising target of anti-tumor therapy.

National-scale data-driven rainfall induced landslide susceptibility mapping for China by accounting for incomplete landslide data

China is one of the countries where landslides caused the most fatalities in the last decades. The threat that landslide disasters pose to people might even be greater in the future, due to climate change and the increasing urbanization of mountainous areas. A reliable national-scale rainfall induced landslide susceptibility model is therefore of great relevance in order to identify regions more and less prone to landsliding as well as to develop suitable risk mitigating strategies. However, relying on imperfect landslide data is inevitable when modelling landslide susceptibility for such a large research area. The purpose of this study is to investigate the influence of incomplete landslide data on national scale statistical landslide susceptibility modeling for China. In this context, it is aimed to explore the benefit of mixed effects modelling to counterbalance associated bias propagations. Six influencing factors including lithology, slope,soil moisture index, mean annual precipitation, land use and geological environment regions were selected based on an initial exploratory data analysis. Three sets of influencing variables were designed to represent different solutions to deal with spatially incomplete landslide information: Set 1(disregards the presence of incomplete landslide information), Set 2(excludes factors related to the incompleteness of landslide data), Set 3(accounts for factors related to the incompleteness via random effects). The variable sets were then introduced in a generalized additive model(GAM: Set 1 and Set 2) and a generalized additive mixed effect model(GAMM: Set 3) to establish three national-scale statistical landslide susceptibility models: models 1, 2 and 3. The models were evaluated using the area under the receiver operating characteristics curve(AUROC) given by spatially explicit and non-spatial cross-validation. The spatial prediction pattern produced by the models were also investigated. The results show that the landslide inventory incompleteness had a substantial impact on the outcomes of the statistical landslide susceptibility models. The cross-validation results provided evidence that the three established models performed well to predict model-independent landslide information with median AUROCs ranging from 0.8 to 0.9.However, although Model 1 reached the highest AUROCs within non-spatial cross-validation(median of 0.9), it was not associated with the most plausible representation of landslide susceptibility. The Model 1 modelling results were inconsistent with geomorphological process knowledge and reflected a large extent the underlying data bias. The Model 2 susceptibility maps provided a less biased picture of landslide susceptibility. However, a lower predicted likelihood of landslide occurrence still existed in areas known to be underrepresented in terms of landslide data(e.g., the Kuenlun Mountains in the northern Tibetan Plateau). The non-linear mixed-effects model(Model 3) reduced the impact of these biases best by introducing bias-describing variables as random effects. Among the three models, Model 3 was selected as the best national-scale susceptibility model for China as it produced the most plausible portray of rainfall induced landslide susceptibility and the highest spatially explicit predictive performance(median AUROC of spatial cross validation 0.84) compared to the other two models(median AUROCs of 0.81 and 0.79, respectively). We conclude that ignoring landslide inventory-based incompleteness can entail misleading modelling results and that the application of non-linear mixed-effect models can reduce the propagation of such biases into the final results for very large areas.

Research on the method of dual-frequency microwave diagnosis of plasma for solving phase integer ambiguity

In this work,microwaves and terahertz waves have performed a dual-frequency combineddiagnosis in high-temperature,large-scale plasma.According to the attenuation and phase shift of electromagnetic waves in the plasma,the electron density and collision frequency of theplasma can be inversely calculated.However,when the plasma size is large and the electron density is high,the phase shift of the electromagnetic wave is large(multiple times 2πperiod).Due to the limitations of the test equipment,the true phase shift is difficult to test accurately or to recover reality.That is,there is a problem of phase integer ambiguity.In order to obtain a phase shift of less than 180°,a higher electromagnetic wave frequency(terahertz wave with 890 GHz)is used for diagnosis.However,the attenuation of the terahertz wave diagnosis is too small(less than 0.1 d B),only the electron density can be obtained,and the collision frequency cannot be accurately obtained.Therefore,a combined diagnosis was carried out by combining twofrequencies(microwave with 36 GHz,terahertz wave with 890 GHz)to obtain electron density and collision frequency.The diagnosis result shows that the electron density is in the range of(0.65–1.5)×1019m^(-3),the collision frequency is in the range of 0.65–2 GHz,and the diagnostic accuracy is about 60%.

Optimization of Co-precipitation Condition for Preparing Molybdenum-Based Sulfur-Resistant Methanation Catalysts

In this study, the e ects of ZrO 2 carrier precursors, MoO 3 loading, and washing treatment on the catalytic performance of M o O 3 /ZrO 2 toward sulfur-resistant methanation were investigated. All the catalysts were prepared by co-precipitation method and further characterized by N 2 adsorption desorption, H 2 -temperature-programmed reduction, X-ray di raction, Raman spectroscopy and transmission electron microscopy. The prepared MoO 3 /ZrO 2 catalysts were tested in a continuous- ow pressurized xed bed reactor for CO methanation. The results revealed that the carrier precursors, MoO3 loading, and wash- ing treatment a ected not only the crystalline phase of Mo species but also the grain size of ZrO 2 carrier and consequently in uenced the MoO 3 /ZrO 2 activity toward sulfur-resistant methanation. The 25 wt% M oO 3 /ZrO 2 catalyst prepared using Zr(NO 3 ) 4 5H 2 O as the precursor and treated by water washing displayed the best activity for sulfur-resistant methanation due to its greater number of octahedral Mo species and smaller ZrO 2 grain size.

Energy dissipation and power deposition of electromagnetic waves in the plasma sheath

Energy dissipation and power deposition of electromagnetic waves(EMW)in the reentry plasma sheath provide an opportunity to investigate‘communication blackout’phenomena.Based on afinite element method(FEM)simulation,we analyze variation of EMW energy dissipation and power deposition profiles dependent on the wave polarization,wave incident angle,plasma density profile and electron collision frequency.Cutoff and resonance of EMW in the plasma sheath are crucial in explaining the regulation of energy dissipation and power deposition.

Real-Time Observation of Protein Transport across Membranes by Femtosecond Sum Frequency Generation Vibrational Spectroscopy

Characterization of conformation kinetics of proteins at the interfaces is crucial for understanding the biornolecular functions and the mechanisms of interfacial biological action. But it requires to capture the dynamic structures of proteins at the interfaces with suffi- cient structural and temporal resolutions. Here, we demonstrate that a ferntosecond sum frequency generation vibrational spectroscopy （SFG-VS） system developed by our group provides a powerful tool for monitoring the real-tirne peptide transport across the membranes with time resolution of less than one second. By probing the real-time SFG signals in the arnide I and arnide A bands as WALP23 interacts with DMPG lipid bilayer, it is found that WALP23 is initially absorbed at the gel-phase DMPG bilayer with a random coil structure. The absorption of WALP23 on the surface leads to the surface charge reversal and thus changes the orientation of rnembrane-bound water. As the DMPG bilayer changes from gel phase into fluid phase, WALP23 inserts into the fluid-phase bilayer with its N-terminal end moving across the membrane, which causes the membrane dehydration and the transition of WALP23 conformation from random coil to mixed helix/loop structure and then to pure α-helical structure. The established system is ready to be employed in characterizing other interracial fast processes, which will be certainly helpful for providing a clear physical picture of the interracial phenomena.

Influence and Analysis of Physical Training on Children's Physique

In recent years,with the rapid development of national economy,people's living standards have been continuously improved,and people's health problems have attracted more and more attention.As the backbone of national development,children's healthy growth is closely related to national competitiveness in the future.However,the time and space for children's activities have been greatly shortened due to the lack of attention to lifestyle for a long time,the rapid construction of urbanization and the influence of modern people's life concept.It has led to the current situation that most children's physique is declining and their physical quality is poor.In 1982,Article 12 of the Constitution of the People's Republic of China clearly stated that the country should develop sports undertakings and carry out mass sports activities to enhance the people's physical fitness.In 2010,the Administrative Measures for Health Care in Nurseries and Kindergartens and the Standards for Health Care in Nurseries and Kindergartens jointly issued by the Ministry of Health and the Ministry of Education of China clearly pointed out that physical exercise plans should be made to adapt to children's physiological characteristics,and sports activities should be carried out according to children's age characteristics.By comparing the experimental data of 6-year-old children before and after physical training in Zhuoyue Children's Sports Center of Zhengzhou City,this paper analyzes the influence of physical training on children's physique and explores ways and means to promote children's physique.

Highly efficient catalyzed by imidazolium-based dual-sulfonic acid functionalized ionic liquids for liquid phase Beckmann rearrangement:experiments and COSMO-RS calculations

A production technique with the high yield and environmentally friendly process need be developed forε-Caprolactam(CPL)in the chemical industry.This technology is highly desired to design and synthesize high--performance catalysts for liquid phase Beckmann rearrangement of cyclohexanone oxime(CHO)to CPL.In this work,3-methyl-1-(propyl-4-sulfonyl)imidazolium methanesulfonate([PHSO_(3)MIM][MSA])with highly efficient and excellent yield is synthesized successfully.When the optimum molar ratio of ZnCl_(2)over[PHSO_(3)MIM][MSA]was 0.02,it exhibits the high selectivity(94%)of CPL at 90℃for 1 h.Interestingly,Fourier-transform infrared(FT-IR)investigations show that the functional Br∅nsted-Lewis acidic types of ionic liquids(ILs)are formed by the uniformly distributed ZnCl_(2)and[PHSO_(3)MIM][MSA].In addition,the hydrogen bond(H-bond)is formed between CHO and ILs.After ten reaction cycles,no significant structure changes are observed in the recovered[PHSO_(3)MIM][MSA]-ZnCl_(2).The solubilities of ILs are predicted by using COSMO-RS model,the results show that[PHSO_(3)MIM][MSA]is a promising candidate for the liquid phase Beckmann rearrangement of CHO into CPL.Finally,a theoretical model of the H-bond interactions between ILs and CHO is further confirmed to support the advance of reaction mechanism.A feasible way is provided for the CPL production technique in the liquid phase Beckmann rearrangement reaction.

Integrated spatial-temporal random speckle spectrometer with high resolution in the C-band

The increasing demand for diverse portable high-precision spectral analysis applications has driven the rapid development of spectrometer miniaturization. However, the resolutions of existing miniaturized spectrometers mostly remain at the nanometer level, posing a challenge for further enhancement towards achieving picometerlevel precision. Here, we propose an integrated reconstructive spectrometer that utilizes Mach–Zehnder interferometers and a tunable diffraction network. Through random tuning in the time domain and disordered diffraction in the space domain, the random speckle patterns closely related to wavelength information are obtained to construct the transmission matrix. Experimentally, we achieve a high resolution of 100 pm and precisely reconstruct multiple narrowband and broadband spectra. Moreover, the proposed spectrometer features a simple structure, strong portability, and fast sampling speed, which has great potential in the practical application of high-precision portable spectral analysis.

Issues and strategies of cathode materials for mild aqueous static zinc-ion batteries

Researchers prefer mild aqueous static zinc-ion batteries(ASZIBs)for their distinct benefits of excellent safety,abundant zinc resources,low cost,and high energy density.However,at the moment there are some issues with the cathode materials of mild ASZIBs,including dissolution,by-products,poor conductivity,and a contentious energy storage system.Consequently,there are numerous difficulties in the development of high-performance mild ASZIBs cathode materials.This overview examines the mechanisms for storing energy and the de-velopments in inorganic,organic,and other novel cathode materials that have emerged in recent years.At the same time,three solutions—structural engineering,interface engineering,and reaction pathway engineering—as well as the difficulties now faced by the cathode materials of mild ASZIBs are forcefully introduced.Finally,a prospect is made regarding the evolution of cathode materials in the future.

E93 promotes transcription of RHG genes to initiate apoptosis during Drosophila salivary gland metamorphosis

20-hydroxyecdysone(20E)induced transcription factor E93 is important for larval–adult transition,which functions in programmed cell death of larval obsolete tissues,and the formation of adult new tissues.However,the apoptosis-related genes directly regulated by E93 are still ambiguous.In this study,an E93 mutation fly strain was obtained by clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9-mediated long exon deletion to investigate whether and how E93 induces apoptosis during larval tissues metamorphosis.The transcriptional profile of E93 was consistent with 3 RHG(rpr,hid,and grim)genes and the effector caspase gene drice,and all their expressions peaked at the initiation of apoptosis during the degradation of salivary glands.The transcription expression of 3 RHG genes decreased and apoptosis was blocked in E93 mutation salivary gland during metamorphosis.In contrast,E93 overexpression promoted the transcription of 3 RHG genes,and induced advanced apoptosis in the salivary gland.Moreover,E93 not only enhance the promoter activities of the 3 RHG genes in Drosophila Kc cells in vitro,but also in the salivary gland in vivo.Our results demonstrated that 20E induced E93 promotes the transcription of RHG genes to trigger apoptosis during obsolete tissues degradation at metamorphosis in Drosophila.

Realizing high-performance all-solid-state batteries with sulfide solid electrolyte and silicon anode:A review

Sulfide solid electrolyte(SE)is one of the most promising technologies for all-solid-state batteries(ASSBs)because of its high ionic conductivity and ductile mechanical properties.In order to further improve the energy density of sulfide-based ASSBs and promote practical applications,silicon anodes with ultrahigh theoretical capacity(4,200 mAh·g^(−1))and rich resource abundance have broad commercial prospects.However,significant challenges including bulk instability of sulfide SEs and poor utilization of silicon materials have severely impeded the ASSBs from becoming viable.In this review,we first introduce the critical bulk properties of sulfide SEs and the most recent improving strategies covering the ionic conductivity,air stability,electrochemical window,mechanical stability,thermostability and solvent stability.Next,we introduce the main factors affecting the compatibility of silicon and sulfide SE,including the carbon’s effect,particle size of silicon,external pressure,silicon composite matrix and the depth of silicon’s lithiation.Finally,we discuss possible research directions in the future.We hope that this review can provide a comprehensive picture of the role of nanoscale approaches in recent advances in ASSBs with sulfide and silicon,as well as a source of inspiration for future research.

Dynamic economic evaluation of hundred megawatt-scale electrochemical energy storage for auxiliary peak shaving

With the rapid development of wind power,the pressure on peak regulation of the power grid is increased.Electro-chemical energy storage is used on a large scale because of its high efficiency and good peak shaving and valley fill-ing ability.The economic benefit evaluation of participating in power system auxiliary services has become the focus of attention since the development of grid-connected hundred megawatt-scale electrochemical energy storage systems(ESS).Based on the relationship between power and capacity in the process of peak shaving and valley filling,a dynamic economic benefit evaluation model of peak shaving assisted by hundred megawatt-scale electrochemi-cal ESS considering the equivalent life of the battery is proposed.The model considers the investment cost of energy storage,power efficiency,and operation and maintenance costs,and analyzes the dynamic economic benefits of dif-ferent energy storage technologies participating in the whole life cycle of the power grid.Then,according to the cur-rent ESS market environment,the auxiliary service compensation price,peak-valley price difference and energy stor-age cost unit price required to make the energy storage technology achieve the balance of payments are calculated,and the economic balance points of different energy storage types are clarified.Finally,based on the measured data of different provincial power grids,the economies of six energy storage types applied to three provincial power grids are compared and analyzed,and the rationality and effectiveness of the relevant models proposed are verified.The work has theoretical guiding significance for the economic benefit evaluation of hundred megawatt-scale electro-chemical energy storage.Highlights 1 A proportional relationship between grid filling power and capacity demand is proposed.It is used to determine the energy storage configuration for auxiliary peak shaving.2 A dynamic economic evaluation model considering energy storage investment and maintenance costs,electric-ity profit,and auxiliary service compensation is proposed.3 In the three provincial power grids,the economics of 6 hundred megawatt-scale electrochemical energy stor-ages are compared and analyzed.4 Auxiliary service compensation,time of day rate,and energy storage cost that enable energy storage to reach an economic equilibrium point are determined.

Emergent antisymmetric wrinkling patterns in films on ridged substrates

We report the formation of antisymmetric wrinkling patterns in films on ridged substrates induced by the buckling instability of the substrates via finite element simulations and experiments.Our simulated results reveal that the uniaxial compression along the ridge can trigger both the wrinkling instability of the film and the lateral buckling instability of the ridge.The latter could change the wrinkles from a symmetric pattern to an antisymmetric pattern in a range of film-substrate modulus ratio and aspect ratio of the ridge profile,as validated by the experimental observations.A three-dimensional phase diagram with four buckling patterns,i.e.,sole ridge buckling pattern,antisymmetric wrinkling pattern with different wavelengths from ridge buckling,symmetric wrinkling pattern without ridge buckling,and antisymmetric wrinkling pattern with the same wavelength as ridge buckling,is built with respect to the uniaxial compression,modulus ratio,and aspect ratio.The results not only elucidate how and when the interplay between the wrinkling instability and the ridge instability results in the formation of the antisymmetric wrinkling pattern but also offer a way to generate controllable complex wrinkling patterns.

Integrated fluorescence excitation,collection,and filtering on a GaN waveguide chip

Fluorescence detection is widely used in biology and medicine,while the realization of on-chip fluorescence detection is vital for the portable and point-of-care test(POCT)application.In this Letter,we propose an efficient fluorescence excitation and collection system using an integrated GaN chip consisting of a slot waveguide and a one-dimensional photonic crystal(1D PC)waveguide.The slot waveguide is used to confine the excitation light for intense light–sample interaction,and the one-trip collection efficiency at the end of slot waveguide is up to 14.65%.More interestingly,due to the introduction of the 1D PC waveguide,the fluorescence signal is directly filtered out,and the excitation light is reflected to the slot waveguide for multiple excitations.Its transmittances for the designed exciting wavelength of 520 nm and the fluorescent wavelength of 612 nm are 0.2%and 85.4%,respectively.Finally,based on numerical analysis,the total fluorescence collection efficiency in our system amounts to 15.93%.It is the first time,to our knowledge,that the concept of an all-in-one-chip fluorescence detection system has been proposed,which paves the way for on-chip fluorescence excitation and collection,and may find potential applications of miniaturized and portable devices for biomedical fluorescence detection.

Interaction between the core and the edge for ion cyclotron resonance heating based on artificial absorption plasma model

In numerical simulations of the ion cyclotron range of frequencies(ICRF)wave heating scheme,core solvers usually focus on wave propagation and absorption mechanisms within the core plasma region.However,the realistic scrape-off layer(SOL)plasma is usually simplified,making it difficult to have deeper understanding of wave propagation and absorption within the SOL.In this work,we employ a cold plasma assumption and an artificial absorption mechanism based on the approach of reference(Zhang et al 2022 Nucl.Fusion 62076032),to study wave propagation and absorption in the realistic SOL plasma of the EAST.During the exponential decay of the total coupled power with respect to the toroidal mode numbers,several fluctuations are observed in the case of low collisional frequencies.The fluctuations may be caused by the cavity modes associated with specific toroidal mode numbers.Due to the presence of cut-off densities,the edge power losses and the total coupled power exhibit different behaviors before and after the cut-off layer is“open”.Furthermore,the simulation results obtained from the kinetic model in reference(Zhang et al 2022 Nucl.Fusion 62076032)is discussed.This suggests that both the core-edge combined model and the artificial mechanism are capable of simulating wave propagation and absorption.

Efficient allelic replacement in rice by gene editing： A case study of the NRT1.1B gene

Summary Precise replacement of an existing allele in commercial cultivars with an elite allele is a major goal in crop breeding. A single nucleotide polymorphism in the NRT1.1B gene between japonica and indica rice is responsible for the improved nitrogen use efficiency in indica rice. Herein, we precisely replaced the japonica NRT1.1B allele with the indica allele, in just one generation, using CRISPR/Cas9 gene-editing technology. No additional selective pressure was needed to enrich the precise replacement events.