Electron relaxation properties of Ar magnetron plasmas

An understanding of electron relaxation properties in plasmas is of importance in the application of magnetrons.An improved multi-term approximation of the Boltzmann equation is employed to study electron transport and relaxation properties in plasmas.Elastic,inelastic and nonconservative collisions between electrons and neutral particles are considered.The expressions for the transport coefficients are obtained using the expansion coefficients and the collision operator term.Numerical solutions of the matrix equations for the expansion coefficients are also investigated.Benchmark calculations of the Reid model are presented to demonstrate the accuracy of the improved multi-term approximation.It is shown that the twoterm approximation is generally not accurate enough and the magnetic fields can reduce the anisotropy of the velocity distribution function.The electron relaxation properties of Ar plasmas in magnetrons for various magnetic fields are studied.It is demonstrated that the energy parameters change more slowly than the momentum parameters.

End-on x-ray backlighting experiments for axial diagnostics of wire-array Z-pinch plasma on PPG-1

An X-pinch axial backlighting system has been designed to quantitatively measure the density distribution of wirearray Z-pinch plasmas. End-on backlighting experiments were carried out on a 200 kA, 100 ns pulsed-power generator（PPG-1） at the Tsinghua University. Compared with side-on backlighting, end-on measurements provide an axial view of the evolution of Z-pinch plasmas. Early stages of 2-, 4-, and 8-wire Z-pinch plasmas were observed via point-projection backlighting radiography with a relatively high success rate. The density distribution of Z-pinch plasma on the r–θ plane was obtained directly from the images with the help of step wedges, and the inward radial velocity was calculated. The ablation rates obtained by X-pinch backlighting experiments are compared in detail with those calculated by the rocket model and the results show consistency.

Effect of photoionisation on initial discharge in air under nanosecond pulse voltage

Effects of photoionisation on the development and electron runaway of the initial discharge in atmospheric air under nanosecond pulse voltage were studied via twodimensional particle-in-cell/Monte Carlo collision simulations.It was found that photoionisation has little effect at the beginning of the initial discharge.However,as the discharge channel gradually develops towards the anode,photoionisation shows greater impacts on the morphology of discharge but has little influence on the velocity of discharge development.Photoionisation does not appear to have a decisive effect on the growth trend of the highest energy of runaway electrons,but it does affect the change rate of the highest energy and overall distribution of electron energy,resulting in a higher proportion of energetic electrons.The difference in the distributions of the electron energy between the two cases,with and without considering photoionisation,can be attributed to the impact of photoionisation on the discharge morphology,which in turn distorted the electric field.The spatial density distributions of the electrons produced by photoionisation further explained the differences.The authors’results explicitly demonstrate the influence of photoionisation on the development and the electron runaway of the initial discharge under nanosecond pulse voltage,which provides more comprehensive knowledge for the atmospheric air gap nanosecond pulse discharge physics.

KMT2D deficiency leads to cellular developmental disorders and enhancer dysregulation in neural-crest-containing brain organoids

KMT2D,a H3K4me1 methyltransferase primarily regulating enhancers,is a leading cause of KABUKI syndrome.This multisystem disorder leads to craniofacial and cognitive abnormalities,possibly through neural crest and neuronal lineages.However,the impacted cell-of-origin and molecular mechanism of KMT2D during the development of KABUKI disease remains unknown.Here we have optimized a brain organoid model to investigate neural crest and neuronal differentiation.To pinpoint KMT2D's enhancer target,we developed a genome-wide cis-regulatory element explorer(GREE)based on single-cell multiomic integration.Single cell RNA-seq revealed that KMT2D-knockout(KO)and patient-derived organoids exhibited neural crest deformities and GABAergic overproduction.Mechanistically,GREE identified that KMT2D targets a roof-plate-like niche cell and activates the niche cell-specific WNT3A enhancer,providing the microenvironment for neural crest and neuronal development.Interestingly,KMT2D-mutated mice displayed decreased WNT3A expression in the diencephalon roof plate,indicating impaired niche cell function.Deleting the WNT3A enhancer in the organoids presented phenotypic similarities to KMT2D-depletion,emphasizing the WNT3A enhancer as the predominant target of KMT2D.Conversely,reactivating WNT signaling in KMT2D-KO rescued the lineage defects by restoring the microenvironment.Overall,our discovery of KMT2D's primary target provides insights for reconciling complex phenotypes of KABUKI syndrome and establishes a new paradigm for dissecting the mechanisms of genetic disorders from genotype to phenotype.

Prevalence of Autism Spectrum Disorder in China:A Nationwide Multi-center Population-based Study Among Children Aged 6 to 12 Years

This study aimed to obtain the first national estimate of the prevalence of autism spectrum disorder(ASD) in Chinese children.We targeted the population of 6 to 12-year-old children for this prevalence study by multistage convenient cluster sampling.The Modified Chinese Autism Spectrum Rating Scale was used for the screening process.Of the target population of 142,086 children,88.5%(n=125,806) participated in the study.A total of 363 children were confirmed as having ASD.The observed ASD prevalence rate was 0.29%(95% CI:0.26%-0.32%) for the overall population.After adjustment for response rates,the estimated number of ASD cases was867 in the target population sample,thereby achieving an estimated prevalence of 0.70%(95% CI:0.64%-0.74%).The prevalence was significantly higher in boys than in girls(0.95%;95% CI:0.87%-1.02% versus 0.30%;95%CI:0.26%-0.34%;P <0.001).Of the 363 confirmed ASD cases,43.3% were newly diagnosed,and most of those(90.4%) were attending regular schools,and 68.8% of the children with ASD had at least one neuropsychiatric comorbidity.Our findings provide reliable data on the estimated ASD prevalence and comorbidities in Chinese children.

Assessing the Accuracy of the Modified Chinese Autism Spectrum Rating Scale and Social Responsiveness Scale for Screening Autism Spectrum Disorder in Chinese Children

The reported prevalence of autism spectrum disorder（ASD） has been increasing rapidly in many parts of the world. However, data on its prevalence in China are largely missing. Here, we assessed the suitability of the modi？ed Chinese version of a newly-developed ASD screening tool, the Modi？ed Chinese Autism Spectrum Rating Scales（MC-ASRS） in screening for ASD in Chi nese children aged 6–12 years, through comparison with the Social Responsiveness Scale（SRS） that has been widely used for ASD screening. We recruited the par ents/caregivers of 1588 typically-developing children and190 children with ASD aged 6–12 years to complete the MC-ASRS and SRS, and evaluated the validity of both scales in discriminating children with ASD from those developing typically. The results showed that MC-ASRSperformed as well as SRS in sensitivity, speci？city, and area-under-the-curve（both [0.95） in receiver operating characteristic analysis, with a fair false-negative rate.These results suggest that MC-ASRS is a promising tool for screening for children with ASD in the general Chinese population.

Modifying the Autism Spectrum Rating Scale(6–18 years)to a Chinese Context:An Exploratory Factor Analysis

The purpose of this study was to explore the psychometric properties of the Chinese version of the autism spectrum rating scale（ASRS）. We recruited 1,625community-based children and 211 autism spectrum disorder（ASD） cases from 4 sites, and the parents of all participants completed the Chinese version of the ASRS. A robust weighted least squares means and variance adjusted estimator was used for exploratory factor analysis. The3-factor structure included 59 items suitable for the current sample. The item reliability for the modi？ed Chinese version of the ASRS（MC-ASRS） was excellent. Moreover,with 60 as the cut-off point, receiver operating characteristic analysis showed that the MC-ASRS had excellent discriminate validity, comparable to that of the unmodi？ed Chinese version（UC-ASRS）, with area under the curve values of 0.952（95% CI： 0.936–0.967） and 0.948（95% CI：0.930–0.965）, respectively. Meanwhile, the con？rm factor analysis revealed that MC-ASRS had a better construct validity than UC-ASRS based on the above factor solution in another children sample. In conclusion, the MC-ASRS shows better ef？cacy in epidemiological screening for ASD in Chinese children.

Range and similarity of hollow cathode discharge in argon

Hollow cathode discharge and micro-hollow cathode discharge have numerous applications in the fields of industry,medical treatment,environmental protection,and analytical chemistry.However,many of them lack the typical features of hollow cathode mode,especially the applications at atmospheric pressure.In order to investigate the underlying basic science of hollow cathode discharge,the hollow cathode discharge in argon was studied by experiments.The range for the operation of the hollow cathode mode in the argon-aluminum device was quantitatively determined to be from 0.8 to 4 Torr cm,no matter how small the cathode cavity is.The atmospheric pressure operation of the hollow cathode mode was realised with the aluminum cathode of a 50μm cavity.The hollow cathode discharges were consistent with Townsend similarity law when the anode was very close to the cathode and the value of p·D was chosen at the lower limit of the range for hollow cathode mode.In contrast,if the anode was moved a little bit far from the cathode and the value of p D was significantly increased,the results followed Allis-White scaling law.The reason for the deviation of Allis-White scaling law from Townsend similarity law was given.

Chinese Norms for the Autism Spectrum Rating Scale

This study aimed to establish norms for the modi？ed Chinese version of the Autism Spectrum Rating Scale（ASRS）. Participants were recruited from Shanghai,Harbin, Guangzhou, and Changsha, China, and their parents and teachers were invited to complete the Chinese Parent version and the Teacher version of the ASRS. In both versions, boys had signi？cantly higher sub-scale scores and total score（T-score） by 1–3 and 4–5 points respectively, than girls（both P ／ 0.001）. Age had weak correlations with some sub-scores and the T-score（r ranged from-0.1859 to 0.0738）, and some reached signi？cance（P ／ 0.03）. The correlations appeared stronger and were more common in females. The T-score based on Chinese norms ideally correlated with the score based on the United States norms in boys and girls for both versions.Norms for the Chinese version of the ASRS for children aged 6–12 years are proposed and may be helpful for screening individuals with autism spectrum disorders from the general population of children.

Sex Differences in Diagnosis and Clinical Phenotypes of Chinese Children with Autism Spectrum Disorder

The aim of this study was to explore the differences between boys and girls in the diagnosis and clinical phenotypes of autism spectrum disorder（ASD） in China＇s mainland. Children diagnosed with ASD（n = 1064, 228 females） were retrospectively included in the analysis. All children were assessed using the Autism Diagnostic Interview-Revised（ADI-R） and Autism Diagnostic Observation Schedule（ADOS）. The results showed that girls scored significantly higher in ADI-R socioemotional reciprocity than boys, and also scored lower in ADI-R and ADOS restricted and repetitive behaviors（RRBs）. Meanwhile, the proportions of girls who satisfied the diagnostic cut-off scores in the ADI-R RRBs domain were lower than in boys（P ／ 0.05）. Our results indicated that girls with ASD show greater socio-emotional reciprocity than boys. Girls also tended to show fewer RRBs than boys, and the type of RRBs in girls differ from those in boys. The ADI-R was found to be less sensitive in girls, particularly for assessment in the RRBs domain.

Similarity of gas discharge in low-pressure argon gaps between two plane-parallel electrodes

The similarity of gas discharge in low-pressure argon gaps between two plane-parallel electrodes was investigated by experiments,numerical simulations and theoretical analysis.It was found by the experiments that the breakdown voltages depend not only on the product of gas pressure and gap length,but also on the aspect ratio of the gap,i.e.U_(b)=f(pd,d/r).It was theoretically proved that U_(b)=f(pd,d/r)is also a special case,the non-uniform electric field between plane-parallel electrodes,of similarity theorem of gas discharge.It was found by the experiments that there exist similar glow discharges only in two gaps with a limited scaled-down factor k.By theoretical analysis,it was explained that the forbidden processes such as the stepwise ionisation and the inelastic collision of the second kind violate the similarity of discharge as k increases,which was verified by the numerical simulations of the discharges with or without these two forbidden processes taken into account.

Rare inherited missense variants of POGZ associate with autism risk and disrupt neuronal development

Excess de novo likely gene-disruptive and missense variants within dozens of genes have been identified in autism spectrum disorder(ASD)and other neurodevelopmental disorders.However,many rare inherited missense variants of these high-risk genes have not been thoroughly evaluated.In this study,we analyzed the rare missense variant burden of POGZ in a large cohort of ASD patients from the Autism Clinical and Genetic Resources in China(ACGC)and further dissected the functional effect of diseaseassociated missense variants on neuronal development.Our results showed a significant burden of rare missense variants in ASD patients compared to the control population(P=4.6×10-5,OR=3.96),and missense variants in ASD patients showed more severe predicted functional outcomes than those in controls.Furthermore,by leveraging published large-scale sequencing data of neurodevelopmental disorders(NDDs)and sporadic case reports,we identified 8 de novo missense variants of POGZ in NDD patients.Functional analysis revealed that two inherited,but not de novo,missense variants influenced the cellular localization of POGZ and failed to rescue the defects in neurite and dendritic spine development caused by Pogz knockdown in cultured mouse primary cortical neurons.Significantly,L1CAM,an autism candidate risk gene,is differentially expressed in POGZ deficient cell lines.Reduced expression of L1cam was able to partially rescue the neurite length defects caused by Pogz knockdown.Our study showed the important roles of rare inherited missense variants of POGZ in ASD risk and neuronal development and identified the potential downstream targets of POGZ,which are important for further molecular mechanism studies.