An Overview of Bearing Candidates for the Next Generation of Reusable Liquid Rocket Turbopumps

There is a consensus in the aerospace field that the development of reusable liquid rockets can effectively reduce the launch expense.The pursuit of a long service life and reutilization highly depends on the bearing components.However,the rolling element bearings(REBs)used in the existing rocket turbopumps present obvious and increasing limitations due to their mechanical contacting mode.For REBs,high rotational speed and long service life are two performance indexes that mutually restrict each other.To go beyond the DN value(the product of the bearing bore and rotational speed)limit of REBs,the major space powers have conducted substantial explorations on the use of new types of bearings to replace the REB.This review discusses,first,the crucial role of bearings in rocket turbopumps and the related structural improvements of REBs.Then,with the prospect of application to the next generation of reusable liquid rocket turbopumps,the bearing candidates investigated by major space powers are summarized comprehensively.These promising alternatives to REBs include fluid-film,foil,and magnetic bearings,together with the novel superconducting compound bearings recently proposed by our team.Our more than ten years of relevant research on fluid-film and magnetic bearings are also introduced.This review is meaningful for the development of long-life and highly reliable bearings to be used in future reusable rocket turbopumps.

Rare-Earth Chalcogenides:A Large Family of Triangular Lattice Spin Liquid Candidates

Frustrated quantum magnets are expected to host many exotic quantum spin states like quantum spin liquid（QSL）, and have attracted numerous interest in modern condensed matter physics. The discovery of the triangular lattice spin liquid candidate YbMgGaO_4 stimulated an increasing attention on the rare-earth-based frustrated magnets with strong spin-orbit coupling. Here we report the synthesis and characterization of a large family of rare-earth chalcogenides AReCh_2（A = alkali or monovalent ions, Re = rare earth, Ch = O,S,Se）. The family compounds share the same structure（R3 m） as YbMgGaO_4,and antiferromagnetically coupled rare-earth ions form perfect triangular layers that are well separated along the c-axis. Specific heat and magnetic susceptibility measurements on NaYbO_2,NaYbS_2 and NaYbSe_2 single crystals and polycrystals, reveal no structural or magnetic transition down to 50 mK. The family, having the simplest structure and chemical formula among the known QSL candidates, removes the issue on possible exchange disorders in YbMgGaO_4. More excitingly, the rich diversity of the family members allows tunable charge gaps, variable exchange coupling, and many other advantages.This makes the family an ideal platform for fundamental research of QSLs and its promising applications.

Practical approach in hepatitis b e antigen-negative individuals to identify treatment candidates

The natural history of chronic hepatitis B is characterized by different phases of infection,and patients may evolve from one phase to another or may revert to a previous phase.The hepatitis B e antigen(HBeAg)-negative form is the predominant infection worldwide,which consists of individuals with a range of viral replication and liver disease severity.Although alanine transaminase(ALT)remains the most accessible test available to clinicians for monitoring the liver disease status,further evaluations are required for some patients to assess if treatment is warranted.Guidance from practice guidelines together with thorough investigations and classifications of patients ensure recognition of who needs which level of care.This article aims to assist physicians in the assessment of HBeAgnegative individuals using liver biopsy or non-invasive tools such as hepatitis B s antigen quantification and transient elastography in addition to ALT and hepatitis B virus DNA,to identify who will remain stable,who will reactivate or at risk of disease progression hence will benefit from timely initiation of anti-viral therapy.

Effects of two novel sugar drug candidates on CYP450 isoforms in different sexed Chinese human liver microsome in vitro

The sex-based differences between the effects of two novel sugar-based drug candidates,a sulfated polymannuroguluronate(SPMG-911)and an acidic oligosaccharide sugar chain compound(AOSC-971),on the enzymes CYP 1A2,CYP2E1 and CYP3A4 of Chinese human liver microsome were investigated.The results showed that neither SPMG-911 nor AOSC-971 have any effect on CYP3A4,AOSC-971 induced the CYP 2E1 in men but have no effect on CYP1A2,SPMG-911 inhibit the CYP1A2 also in men but have no effect on CYP2E1.The results are useful for their safety evaluation,as well as for the prediction of inter-drug interactions associated with the two drugs.

Fano Resonances Can Provide Two Criteria to Distinguish Majorana Bound States from Other Candidates in Experiments

There are still debates on whether the observed zero energy peak in the experiment by Stevan et al. [Science 346 （2014） 602] reveals the existence of the long pursued Ala.jorana bound states （MBSs）. We propose that, by mounting two scanning tunneling microscopic tips on top of the topological superconducting chain and measuring the transmission spectrum between these two metallic tips, there are two kinds of characteristics on the spectrum that are caused by A.IBSs uniquely： One is symmetric peaks with respect to zero energy and the other is 4~r period caused by a nearby dosephson junction. The former refers to the fact that MBSs are eomposited by Alajorana fermions which distributed in the particle and hole subspaees equally. The latter is based on the well known 4w period of Josephson effect in topological superconductor. We think that such two characteristics can be used as criteria to distinguish MBSs from other candidates, such as impurities, Kondo effect and traditional Andreev bound states.

Multislice spiral CT angiography in evaluation of liver transplantation candidates

BACKGROUND: Orthotopic liver transplantation has be- come the treatment of choice for patients with end-stage liver disease. This study was designed to study whether multislice spiral CT angiography (MSCTA) could be used for preoperative evaluation for orthotopic liver transplanta- tion candidates. METHODS: Eighty consecutive potential candidates for liver transplantation were evaluated with dual-phase three-di- mensional CT angiography (3DCTA). The arterial-phase was used to create vascular maps of the celiac axis (inclu- ding the origin of the hepatic common artery, left gastric artery and splenic artery) and origin of the superior mesen- teric artery. The portal venous-phase was used to analyze portal vein thrombosis and collateral vascularization of the portal vein. Statistical analyses were made using the chi- square test for differences between hepatic arterial anatomy of 80 patients and Michel's anatomy of 200 patients. Appearance of MSCTA and operative results of 16 patients were analyzed. RESULTS; Sixty-two patients (77.5%) showed conven- tional and 18 (22.5%) nonconventional hepatic arterial anatomy. A significant difference was found between the two groups in anatomy of the hepatic artery (P <0.05). Celiac axis stenosis was observed in 6 patients, SA aneu- rysm in 2, small-caliber hepatic arterial vessels in 2, and portal vein thrombosis in 15. Vascular structures of 16 ope- rative patients were well defined. CONCLUSION: As a noninvasive examination, MSCTA can provide a comprehensive preoperative vascular evalua- tion for liver transplantation candidates.

Survey of Temporomandibular Disorder in Male Candidates of Conscription Age

[Objectives] To study the temporomandibular disorder(TMD) in male candidates of conscription age. [Methods] The TMD was surveyed in 2 152 young males who participated in 2015, 2016 and 2017 physical examinations for conscription in Qingzhou City, Weifang of Shandong Province. [Results] Cases with previous positive symptoms and with positive clinical signs respectively accounted for 5.02% and 18.91% of the whole respondents. Among the three major symptoms, the occurrence of clicking, accounting for 17.7% of the total case amount, ranked the first; among 407 cases with positive clinical signs, the top two symptoms were simple clicking(50.86%) and clicking with abnormal mandibular movement(36.85%). [Conclusions] TMD occurs in male candidates of conscription age with a relatively high occurrence, but most cases are mild with clicking as the major symptom.

Women Political Candidates The Malaysian Media and Their Concerns

Globally, women now play a key role in economic, political, and social cultural affairs, and Malaysia is no exception. Equitable representation by women in the political arena is viewed as crucial in the improvement of women＇s participation in the decision-making process. Nevertheless, though women have made and make great contributions in both the private and public spheres, a review of media＇s coverage of women in the public realm shows a strong tendency to relegate women to mainly domestic affairs. This is consistent with findings from studies on women political candidates＇ image during campaign issues that showed that though women candidates attempted to present themselves in decisive and assertive ways, gender stereotyping was dominant in the media agenda and persistent biases typical of traditional gender representations in the media prevailed. There is very little research in Malaysia on how the media frames women candidates during campaign periods, or what issues are aligned with women candidates. The construction of images of women political candidates, in particular, is often omitted in most research on the General Election. This study analyses how women candidates were covered in selected Malaysian newspapers in the 2008 General Election. The types of issues women political candidates are identified with in the newspapers are also analysed.

Analysis and Strategy Research on the Mathematics Learning Situation of the Postgraduate Candidates

This study takes the students who intend to study for graduate students as the research object,and makes a questionnaire survey on the mathematics learning situation and learning platform of the postgraduate candidates.Questionnaires were distributed online and offline,and a total of 326 valid questionnaires were collected.Based on 326 questionnaires,this paper analyzes the current learning situation of mathematics in the postgraduate entrance examination and studies the strategies based on the present situation,which points out the direction for the construction of mathematics learning and communication platform based on the needs of postgraduate entrance examination.

Investigating the Relationship Between Emotional Intelligence and Personality Types Among Nursing Candidates in Ardebil University, in Iran

Personality characteristics of each people are unique. It seems that these features of personality have an impact on emotional intelligence and ability to interact with people in a social environment. This study was conducted to investigate the relationship between emotional intelligence and personality types of nursing students. The research was descriptive and correlative. The study population consisted of Ardebil University of senior nursing candidates in 2011-2012. The study sample included 125 people. Assessment tools were the Bar-on Emotional Intelligence Inventory and MBTI （Myers-Briggs Type Indicator） personality type questionnaire. The data were analyzed by SPSS 20 （T-test, analysis of variance, Pearson correlation and multiple regression with significant level P〈0 .05）. Pearson correlation coefficients showed there is a significant inverse between variables extroversion-introversion and emotional intelligence with level of .01 （r=-522）. Therefore, personality characteristics impact on emotional intelligence of students. Thus, more research of emotional intelligence and personality characteristics is necessary at different levels to selection for nursing profession.

Each Has His Own Place──The New Life of Two Soul Boy Candidates

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CAS-TWAS President’s Fellowship Programme for PhD Candidates from Developing Countries

Call for ApplicationsIntroduction According to a new agreement between the Chinese Academy of Sciences （CAS） and the academy of sciences for the developing world （TWAS）, up to 140 students/scholars per year from the developing world will be sponsored to travel to China for up to four years of PhD study and research.

Identification of genes for drought resistance and prediction of gene candidates in soybean seedlings based on linkage and association mapping

Drought is one of the primary abiotic stress factors affecting the yield,growth,and development of soybeans.In extreme cases,drought can reduce yield by more than 50%.The seedling stage is an important determinant of soybean growth:the number and vigor of seedlings will affect growth and yield at harvest.Therefore,it is important to study the drought resistance of soybean seedlings.In this study,a recombinant inbred line(RIL)population comprising 234 F_(6:10)lines(derived from Zhonghuang35×Jindou 21)and a panel of 259 soybean accessions was subjected to drought conditions to identify the effects on phenotypic traits under these conditions.Using a genetic map constructed by single nucleotide polymorphism(SNPs)markers,18 quantitative trait loci(QTL)on 7 soybean chromosomes were identified in two environments.This included 9 QTL clusters identified in the RIL population.Fifty-three QTL were identified in 19 soybean chromosomes by genome-wide association analysis(GWAS)in the panel of accessions,including 69 significant SNPs(-log_(10)(P)≥3.97).A combination of the two populations revealed that two SNPs(-log_(10)(P)≥3.0)fell within two of the QTL(qPH7-4 and qPH7-6)confidence intervals.We not only re-located several previously reported drought-resistance genes in soybean and other crops but also identified several non-synonymous stress-related mutation site differences between the two parents,involving Glyma.07 g093000,Glyma.07 g093200,Glyma.07 g094100 and Glyma.07 g094200.One previously unreported new gene related to drought stress,Glyma.07 g094200,was found by regional association analysis.The significant SNP CHR7-17619(G/T)was within an exon of the Glyma.07 g094200 gene.In the RIL population,the DSP value of the"T"allele of CHR7-17619 was significantly(P<0.05)larger than the"G"allele in different environments.The results of our study lay the groundwork for cloning and molecular marker-assisted selection of droughtresistance genes in soybeans at the seedling stage.

An efficient algorithm to generate candidates in discovering frequent episodes

One of the important steps in mining event sequences is to find frequent episodes. Once the frequent episodes are discovered, rules about temporal relationships can he derived. In this paper, an cfficient algorithm for discovering frequent episodes is presented based on the level-wise search algorithm WINEPI. The proposed algorithm gains hetter candidate generation quality by introducing a new Lemma to help to target the combinations of episodes that are interesting in the next level and thins reduces the execution time. Experimental results on artificial and real data show the enhanced efficiency of the algorithm.

Frailty in kidney transplant candidates and recipients: pathogenesis and intervention strategies

With the rapid aging of the global population posing a serious problem,frailty,a non-specific state that reflects physiological senescence rather than aging in time,has become more widely addressed by researchers in various medical fields.A high prevalence of frailty is found among kidney transplant(KT)candidates and recipients.Therefore,their frailty has become a research hotspot in the field of transplantation.However,current studies mainly focus on the cross-sectional survey of the incidence of frailty among KT candidates and recipients and the relationship between frailty and transplantation.Research on the pathogenesis and intervention is scattered,and relevant review literature is scarce.Exploring the pathogenesis of frailty in KT candidates and recipients and determining effective intervention measures may reduce waiting list mortality and improve the long-term quality of life of KT recipients.Therefore,this review explains the pathogenesis and intervention measures for frailty in KT candidates and recipients to provide a reference for the formulation of effective intervention strategies.

Genetic dissection and validation of a major QTL for grain weight on chromosome 3B in bread wheat(Triticum aestivum L.)

Grain weight is one of the key components of wheat(Triticum aestivum L.)yield.Genetic manipulation of grain weight is an efficient approach for improving yield potential in breeding programs.A recombinant inbred line(RIL)population derived from a cross between W7268 and Chuanyu 12(CY12)was employed to detect quantitative trait loci(QTLs)for thousand-grain weight(TGW),grain length(GL),grain width(GW),and the ratio of grain length to width(GLW)in six environments.Seven major QTLs,QGl.cib-2D,QGw.cib-2D,QGw.cib-3B,QGw.cib-4B.1,QGlw.cib-2D.1,QTgw.cib-2D.1 and QTgw.cib-3B.1,were consistently identified in at least four environments and the best linear unbiased estimation(BLUE)datasets,and they explained 2.61 to 34.85%of the phenotypic variance.Significant interactions were detected between the two major TGW QTLs and three major GW loci.In addition,QTgw.cib-3B.1 and QGw.cib-3B were co-located,and the improved TGW at this locus was contributed by GW.Unlike other loci,QTgw.cib-3B.1/QGw.cib-3B had no effect on grain number per spike(GNS).They were further validated in advanced lines using Kompetitive Allele Specific PCR(KASP)markers,and a comparison analysis indicated that QTgw.cib-3B.1/QGw.cib-3B is likely a novel locus.Six haplotypes were identified in the region of this QTL and their distribution frequencies varied between the landraces and cultivars.According to gene annotation,spatial expression patterns,ortholog analysis and sequence variation,the candidate gene of QTgw.cib-3B.1/QGw.cib-3B was predicted.Collectively,the major QTLs and KASP markers reported here provide valuable information for elucidating the genetic architecture of grain weight and for molecular marker-assisted breeding in grain yield improvement.

Mining elite loci and candidate genes for root morphology-related traits at the seedling stage by genome-wide association studies in upland cotton(Gossypium hirsutum L.)

Root system architecture plays an essential role in water and nutrient acquisition in plants,and it is significantly involved in plant adaptations to various environmental stresses.In this study,a panel of 242 cotton accessions was collected to investigate six root morphological traits at the seedling stage,including main root length(MRL),root fresh weight(RFW),total root length(TRL),root surface area(RSA),root volume(RV),and root average diameter(AvgD).The correlation analysis of the six root morphological traits revealed strong positive correlations of TRL with RSA,as well as RV with RSA and AvgD,whereas a significant negative correlation was found between TRL and AvgD.Subsequently,a genome-wide association study(GWAS)was performed using the root phenotypic and genotypic data reported previously for the 242 accessions using 56,010 single nucleotide polymorphisms(SNPs)from the CottonSNP80K array.A total of 41 quantitative trait loci(QTLs)were identified,including nine for MRL,six for RFW,nine for TRL,12 for RSA,12 for RV and two for AvgD.Among them,eight QTLs were repeatedly detected in two or more traits.Integrating these results with a transcriptome analysis,we identified 17 candidate genes with high transcript values of transcripts per million(TPM)≥30 in the roots.Furthermore,we functionally verified the candidate gene GH_D05G2106,which encodes a WPP domain protein 2in root development.A virus-induced gene silencing(VIGS)assay showed that knocking down GH_D05G2106significantly inhibited root development in cotton,indicating its positive role in root system architecture formation.Collectively,these results provide a theoretical basis and candidate genes for future studies on cotton root developmental biology and root-related cotton breeding.

Genetic dissection and origin of pleiotropic loci underlying multilevel fiber quality traits in upland cotton(Gossypium hirsutum L.)

Cotton fiber quality is a persistent concern that determines planting benefits and the quality of finished textile products.However,the limitations of measurement instruments have hindered the accurate evaluation of some important fiber characteristics such as fiber maturity,fineness,and neps,which in turn has impeded the genetic improvement and industrial utilization of cotton fiber.Here,12 single fiber quality traits were measured using Advanced Fiber Information System(AFIS)equipment among 383 accessions of upland cotton(Gossypium hirsutum L.).In addition,eight conventional fiber quality traits were assessed by the High Volume Instrument(HVI)System.Genome-wide association study(GWAS),linkage disequilibrium(LD)block genotyping and functional identification were conducted sequentially to uncover the associated elite loci and candidate genes of fiber quality traits.As a result,the previously reported pleiotropic locus FL_D11 regulating fiber length-related traits was identified in this study.More importantly,three novel pleiotropic loci(FM_A03,FF_A05,and FN_A07)regulating fiber maturity,fineness and neps,respectively,were detected based on AFIS traits.Numerous highly promising candidate genes were screened out by integrating RNA-seq and qRT-PCR analyses,including the reported GhKRP6 for fiber length,the newly identified GhMAP8 for maturity and GhDFR for fineness.The origin and evolutionary analysis of pleiotropic loci indicated that the selection pressure on FL_D11,FM_A03 and FF_A05 increased as the breeding period approached the present and the origins of FM_A03 and FF_A05 were traced back to cotton landraces.These findings reveal the genetic basis underlying fiber quality and provide insight into the genetic improvement and textile utilization of fiber in G.hirsutum.

Fine mapping and characterization of stripe rust resistance gene YrAYH in near-isogenic lines derived from a cross involving wheat landrace Anyuehong

Stripe rust,caused by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease in wheat worldwide.Discovering and characterizing new resistance genes/QTL is crucial for wheat breeding programs.In this study,we fine-mapped and characterized a stripe rust resistance gene,YRAYH,on chromosome arm 5BL in the Chinese wheat landrace Anyuehong(AYH).Evaluations of stripe rust response to prevalent Chinese Pst races in near-isogenic lines derived from a cross of Anyuehong and Taichung 29 showed that YrAYH conferred a high level of resistance at all growth stages.Fine mapping using a large segregating population of 9748 plants,narrowed the YRAYH locus to a 3.7 Mb interval on chromosome arm 5BL that included 61 annotated genes.Transcriptome analysis of two NIL pairs identified 64 upregulated differentially expressed genes(DEGs)in the resistant NILs(NILs-R).Annotations indicated that many of these genes have roles in plant disease resistance pathways.Through a combined approach of fine-mapping and transcriptome sequencing,we identified a serine/threonine-protein kinase SRPK as a candidate gene underlying YrAYH.A unique 25 bp insertion was identified in the NILs-R compared to the NILs-S and previously published wheat genomes.An InDel marker was developed and co-segregated with YrAYH.Agronomic trait evaluation of the NILs suggested that YrAYH not only reduces the impact of stripe rust but was also associated with a gene that increases plant height and spike length.

Protein A immunoadsorption therapy in the highly sensitized kidney transplant candidates

Background Sensitization in transplant candidates increases risk of irreversible immunologic injury of graft in the early period postoperatively. Elimination of anti-human leukocyte antigen （HLA） antibodies using protein A immunoadsorption （IA） might benefit these patients.Methods Protein A IA was used in 21 patients with high panel reactive antibody （PRA）. The patients had IA 1-6 times （median 5 times） with the interval period was 2-5 days （median 2.5 days）.Results Total 67 IA procedures were carried out smoothly in all patients. IA treatment reduced PRA I （pre （31.4±3.8）% vs. post （24.4±3.4）%, P 〈0.01） and II （pre （37.1±4.3）% vs. post （34.1±3.9）%, P 〈0.01）. However, PRA did not change in some patients after the treatment. The serum immunoglobulin （IgG, IgM and IgA） and complement C3, C4 level were decreased significantly. Hemoglobin and albumin levels were slightly decreased associated with IA procedures. Flu-like symptoms were observed in a few of cases during the procedure but generally mild and transient.Conclusion Protein A IA is capable to efficiently remove serum immunoglobulin and complement, reduce HLA class I and class II PRA in high sensitized transplant candidates, which is likely to benefit the kidney transplantation in these patients.