Surface contact behavior of functionally graded thermoelectric materials indented by a conducting punch

The contact problem for thermoelectric materials with functionally graded properties is considered.The material properties,such as the electric conductivity,the thermal conductivity,the shear modulus,and the thermal expansion coefficient,vary in an exponential function.Using the Fourier transform technique,the electro-thermoelastic problems are transformed into three sets of singular integral equations which are solved numerically in terms of the unknown normal electric current density,the normal energy flux,and the contact pressure.Meanwhile,the complex homogeneous solutions of the displacement fields caused by the gradient parameters are simplified with the help of Euler’s formula.After addressing the non-linearity excited by thermoelectric effects,the particular solutions of the displacement fields can be assessed.The effects of various combinations of material gradient parameters and thermoelectric loads on the contact behaviors of thermoelectric materials are presented.The results give a deep insight into the contact damage mechanism of functionally graded thermoelectric materials(FGTEMs).

Correlations between Light Rare Earth Elements in Soil and Navel Orange Tree System in Gannan Area

The total content of light rare earth elements( LREEs) in the soil of navel orange orchards of Gannan area is greater than that of heavy rare earth elements( HREEs). Appropriate content of LREE can not only promote the growth of navel oranges,and it is also conducive to human health. On the basis of exploring the correlations between the content of LREE in the soil of navel orange orchards of Gannan area and the contents of LREE in navel orange leaves and fruit,the influence mechanism of LREEs on the quality of navel oranges was revealed. In this study,with two Newhall navel orange orchards with different soil LREEs background levels in Xinfeng County as the research object,the changes in the content of LREE( lanthanum,La; cerium,Ce; praseodymium,Pr; neodymium,Nd) in leaves and fruit of navel orange at different growth stages were analyzed using Inductively Coupled Plasma-Mass Spectrometry( ICP-MS),and the correlations between the content of LREE in the soil,navel orange leaves and navel orange fruit were studied. The results showed that the contents of the four kinds of LREEs in the soil ranked as Ce > La > Nd > Pr,and there were significant differences among them( P < 0. 01). Navel orange leaves and fruit have selective and heterogenic absorption for LREEs. At different growth stages,La showed the highest accumulation amount in the leaves and fruit of navel orange; and the content of LREE in the leaves of navel orange increased first and then decreased,while that in the fruit of navel orange showed continuous decrease. During the migration of LREEs from soil to leaves to fruit,the content of LREE decreased rapidly as the migration distance increased. The accumulation amount of LREE in navel orange was positively correlated with the content of LREE in the soil. The correlation between the content of LREE in the leaves and fruit of navel orange was greatest. Among the four kinds of LREEs,the correlation of La was greatest,followed by Ce,indicating that the accumulation amount of LREE in the navel orange body was affected by the element types.

SYNGAP1基因相关儿童癫痫临床特点和基因分析

目的总结SYNGAP1基因相关儿童癫痫的临床特点。方法回顾性收集首都医科大学附属北京儿童医院神经内科2017年3月至2020年10月就诊的13例SYNGAP1基因变异相关癫痫患儿,并进行随访,对其临床特点、脑电图、头颅影像学、基因结果、治疗等进行总结。结果13例患儿(男4例、女9例)随访到12例,末次随访年龄5岁7月龄(3岁1月龄至9岁)。癫痫发作起病年龄为2岁(4月龄至3岁),发作类型包括眼睑肌阵挛伴或不伴失神(9例)、肌阵挛发作(5例)、不典型失神(4例)、可疑失张力发作(4例)、跌倒发作(6例,具体发作类型不详),发作频率每日数次到百余次。4例表型类似肌阵挛-失张力综合征。10例发作有诱因,包括进食(5例)、情绪(5例)、发热(3例)、声音(2例)、劳累(2例)等。10例患儿脑电图提示9例发作间期广泛性或局灶性痫样放电,监测到不典型失神4例、肌阵挛发作2例和眼睑肌阵挛伴失神发作1例。12例中9例加用丙戊酸钠均有效(发作减少50%以上),5例联用左乙拉西坦3例有效,至末次随访3例发作相对控制(6个月至1年1个月),余7例仍有发作(数日1次或每日数次)。13例均存在发育落后(语言落后为著),2例重度,10例中度,1例轻度。13例患儿携带SYNGAP1基因变异,均为新生变异,包括12个变异位点。其中移码变异4个,无义变异4个,错义变异2个,剪切位点变异2个。结论SYNGAP1基因相关儿童癫痫起病年龄较早,发作类型多样,主要发作类型为眼睑肌阵挛伴或不伴失神,还可有肌阵挛发作、不典型失神、跌倒发作等。丙戊酸治疗多有效,部分可为药物难治性癫痫。患儿存在不同程度发育迟缓,以语言落后为著。

Cryo-electron microscopy reconstructions of two types of wild rabbit hemorrhagic disease viruses characterized the structural features of Lagovirus

Rabbit hemorrhagic disease was described in China in 1984 and can cause hemorrhagic necrosis of the liver within two or three days after infection.The etiological agent,rabbit hemorrhagic disease virus(RHDV),belongs to the Lagovirus genus in the Caliciviridae family.Compared to other calicivirus,such as rNV and SMSV,the structure of Lagovirus members is not well characterized.In this report,structures of two types of wild RHDV particles,the intact virion and the core-like particle(CLP),were reconstructed by cryo-electron microscopy at 11Åand 17Å,respectively.This is the first time the 3D structure of wild caliciviruses CLP has been provided,and the 3D structure of intact RHDV virion is the highest resolution structure in Lagovirus.Comparison of the intact virion and CLP structures clearly indicated that CLP was produced from the intact virion with the protrusion dissociated.In contrast with the crystal structures of recombinant Norovirus and San Miguel sea lion virus,the capsomers of RHDV virion exhibited unique structural features and assembly modes.Both P1 and P2 subdomains have interactions inside the AB capsomer,while only P2 subdomains have interaction inside CC capsomer.The pseudo atomic models of RHDV capsomers were constructed by homology modeling and density map fitting,and the rotation of RHDV VP60 P domain with respect to its S domain,compared with SMSV,was observed.Collectively,our cryo-electron microscopic studies of RHDV provide close insight into the structure of Lagovirus,which is important for functional analysis and better vaccine development in the future.

Clinical phenotype features and genetic etiologies of 38 children with progressive myoclonic epilepsy

Background:Progressive myoclonic epilepsy(PME)is a group of neurodegenerative diseases with genetic heterogeneity and phenotypic similarities,and many cases remain unknown of the genetic causes.This study is aim to summarize the clinical features and study the genetic causes of PME patients.Methods:Sanger sequencing of the target gene,Next Generation Sequencing(NGS)panels of epilepsy,trio-based Whole Exome Sequencing(WES)and detection of cytosine-adenine-guanine(CAG)repeat number were used to investigate the genetic causes of PME patients.Results:Thirty-eight children with PME whose seizure onset age ranged from 3 months to 12 years were collected from February 2012 to November 2019 in three hospitals in Beijing,China.The seizure types included myoclonic seizures(n=38),focal seizures(n=19),generalized tonic-clonie seizure(GTCS)(n=13),absence seizures(n=4),atonic seizures(n=3),epileptic spasms(n=2)and tonic seizures(n=1).Twenty-seven cases were sporadic and 11 had family members affected.Established PME-related genes were identified in 30 out of 38(78.9%)patients who had either recessively inherited or de novo heterozygous mutations.Among these 30 cases,there were 12 cases(31.6%)of neuronal ceroid lipofuscinoses(the causing gene contains TPP1,PPT1,CLN5,CLN6 and MFSD8),two cases of sialidosis(the causing gene is NEU1),two cases of neuronopathic Gaucher disease(the causing gene is GBA),one case of spinal muscular atrophy-progressive myoclonic epilepsy(the causing gene is ASAH1),four cases of KCNC1 mutation-related PME,four cases of KCTD7 mutation-related PME,two cases of TBC1D24 mutation-related PME,one case of GOSR2 related PME,and two of dentatorubral-pallidoluysian atrophy(the causing gene is ATN1).In total,13 PME genes were identified in our cohort.The etiology was not clear in eight patients.Conclusion:PME is a group of clinically and genetically heterogeneous diseases.Genetic diagnosis was clear in 78.9%of PME patients.Various of genetic testing methods could increase the rate of genetic diagnosis.Neuronal ceroid lipofuscinoses(NCL)is the most common etiology of PME in children.Nearly one third PME children were diagnosed with NCL.GOSR2 related PME was in our cohort in Asia for the first time.

Bilateral globus pallidus internus-deep brain stimulation in a 5-year-old boy with SGCE-related myoclonus dystonia syndrome

To the editor:Myoclonus-dystonia syndrome(MDS)(OMIM15990)is a heritable disorder characterized by early onset subcortical myoclonic jerks and/or less prominent dystonia.This leads to disability and is often refractory to medical treatment.1 Deep brain stimulation(DBS)for the treatment of refractory MDS has been proven effective in adults for reducing both myoclonic jerks and dystonia.1,2,3 Here,we describe the application of bilateral globus pallidus internus(GPi)DBS in a 5-year-old boy diagnosed with MDS.