Comparative transcriptome profiling of the fertile and sterile flower buds of a dominant genic male sterile line in sesame (Sesamum indicum L.)

Expressions and annotations of the 1502 differentially expressed unigenes in sesame. (XLSX 338 kb

A compliant-mechanism-based lockable prismatic joint for high-load morphing structures

Lockable joints are widely used in robotic systems and adaptive structures for energy management and/or topology reconfiguration. However, it is still challenging to design a joint with desired properties, including high locking load, infinite locking positions, short switching time, energy-efficient control, and a compact and lightweight structure. This paper aims at this open problem by presenting a novel piezoelectric (PZT) actuated lockable prismatic joint. This joint is a compliant mechanism (CM) consisting of a compound bridge-type compliant mechanism (CBCM) and a pair of compound multibeam parallelogram mechanisms (CMPMs). It can produce the required input/output stiffness to transmit large forces for high-load locking. It can also provide a desired input/output motion range for PZT actuation-based unlocking and for facilitating preloading adjustment. An analytical model is presented based on a compliance matrix method and the nonlinear model of the CMPM to predict the joint's static characteristics under various input/output conditions. A two-step optimization framework is proposed for locking applications. The theoretical study and nonlinear FEA/experimental verification confirm the feasibility of the design and the accuracy of the proposed model

Hydrogen isotopic characteristic of hydrocarbon gas pyrolyzed by herbaceous swamp peat in hydrous and anhydrous thermal simulation experiments

In order to understand the influence of diagenetic water medium on hydrogen isotope of thermogenic coalbed gas, the hydrous and anhydrous pyrolytic simulation experiments have been carried out on herbaceous peat. We studied hydrogen isotope composition and its difference and evolution pattern of the pyrolysis hydrocarbon gases It was observed that diagenetic water medium exerts a significant influence on hydrogen isotopic composition of the pyrolysis hydrocarbon gases. The experiment added water with heavier hydrogen isotopic composition than peat-formed environmental water generated hydrocarbon gases with heavier hydrogen isotopic compositions. When peat was subject to continuous pyrolysis until 5.5%Ro, average δD values of the generated methane, ethane and propane were increased by 74‰, 42‰ and 66‰, respectively. It was considered that the reason for hydrous simulation experiment to increase hydrogen isotopic value of pyrolytic hydrocarbon gases is due to isotopic exchange between water-derived hydrogen and organic hydrogen. Mathematical models between the δD values of the hydrocarbon gases generated under the participation of freshwater with higher δD values and Ro values as well as between δD values of the generated hydrocarbon gases were established. These research results provide a scientific basis for the genetic study of thermogenic coalbed methane pyrolyzated by coal-forming materials formed in herbaceous marsh under the participation of diagenetic water media. Keywords: Simulation experiment, Gas product, Hydrogen isotope, Diagenetic water medium, Influencing facto

Sequencing the exons of human glucocorticoid receptor (NR3C1) gene in Han Chinese with high-altitude pulmonary edema

Abstract Background High-altitude pulmonary edema (HAPE) is a serious acute mountain sickness that mainly occurs in non-acclimatized individuals after rapid ascent to high altitude. The precise etiology of HAPE remains unclear. This study aimed to investigate whether NR3C1 gene polymorphism is associated with the susceptibility to HAPE. Methods The exons of NR3C1 gene were sequenced by a ABI 3730 DNA analyzer in 133 HAPE patients and matched 135 healthy Han Chinese controls from the Yushu area in Qinghai (the altitude greater than 3500 m). Results DNA sequencing showed the heterozygous substitutions at codon 588 (rs6194) in exon 6 and 766 (rs6196) in exon 9 of NR3C1 gene. The genotypic distributions and allelic frequencies of NR3C1 SNP rs6194 showed significant differences in two groups (P < 0.05). The frequencies of the C allele were significantly higher in the HAPE group than in the control group (P < 0.05) with an odds ratio of 3.009 (95% CI = 1.250-7.244). There were no differences in genotypic and allelic frequencies in rs6196 polymorphism between the two groups. Conclusions NR3C1 gene rs6194 polymorphism is correlated with HAPE susceptibility. CC genotype and C allele of rs6194 polymorphism might increase the risk of HAPE in Han Chinese

Cytological characterization and molecular mapping of a novel recessive genic male sterility in sesame (Sesamum indicum L.).

Recessive genic male sterility (RGMS) has great potential for F1 hybrid seeds production in sesame (Sesamum indicum L.). However, it is not yet widely used in practice due to poor understanding of the underlying mechanism in RGMS. Previously, we have developed a novel sesame RGMS line (D248A) controlled by a single recessive gene. To elucidate its cytological mechanism, histological observations were carried out in sterile and fertile buds. The results indicated that abnormality in D248A began at microspore mother cell stage and persisted until microspore stage. The microsporocytes had less cytoplasm and no obvious nucleus. Normal meiosis failed in microspore mother cells. Cytoplasm condensation and vacuolation frequently occurred in tetrads, leading to the production of crumpled and abortive microspores. To develop molecular markers for breeding of hybrid lines, InDel and SSR markers were analyzed in a fertility segregating NIL population constructed by sib-mating D248A with D248B. Five markers were identified for the male sterile gene (Ms), with a respective genetic distance of 1.47 and 5.17 cM for the two closest markers (SB2993 and LG1-170) on both sides. The Ms gene was further anchored into a 108-kb interval in the downstream of chromosome 1, within which 15 genes were predicted and four were likely to be responsible for male sterility. These findings provide a deeper understanding of the mechanism underlying RGMS in sesame

A Simplified Method for Inverse Kinematics of a Flexible Panel Continuum Robot for Real-Time Shape Morphing

Continuum robots are good candidates for shape morphing. However, due to the coupled problem between kinematics and statics, the inverse kinematics of continuum robots is highly nonlinear, posing a challenging problem for real-time applications. This paper presents a simplified approach to solving the inverse kinematics of a flexible panel continuum robot efficiently. Through an experiment, two approximate relationships are discovered. First, the arc length of the middle backbone can be estimated from the arc lengths of the two panels; second, the length difference between the two panels can be related to the tip angle of the end-effector. Based on these two discovered relationships, a simplified inverse kinematics method is proposed based on a constant curvature model. This method has been validated by the experimental data with high accuracy of less than 2% error, thereby demonstrating the effectiveness of the proposed method for real-time applications

The complete chloroplast genome sequence of Pennisetum flaccidum (Poaceae)

Pennisetum flaccidum Grisebach is a typical high-quality forage and adrought-tolerant grass. In this study, we firstly reported the complete chloroplast (cp) genome of P. flaccidum, which was 138,336 bp in length, including a pair of inverted repeats (IR: 22,293 bp), a large single copy (LSC: 81,329 bp), and a small single copy (SSC: 12,421 bp) region. A total of 131 genes were annotated, containing seven rRNA genes, 38 tRNA genes, and 86 protein-coding genes. The GC content of the cp genome was 38.63%. The maximum-likelihood (ML) phylogenetic tree indicated that P. flaccidum was closely related to P. cetaceum in Poaceae

Analysis of expression sequence tags from a full-length-enriched cDNA library of developing sesame seeds (<it>Sesamum indicum</it>)

Abstract Background Sesame (Sesamum indicum) is one of the most important oilseed crops with high oil contents and rich nutrient value. However, genetic improvement efforts in sesame could not get benefit from molecular biology technology due to poor DNA and RNA sequence resources. In this study, we carried out a large scale of expressed sequence tags (ESTs) sequencing from developing sesame seeds and further conducted analysis on seed storage products-related genes. Results A normalized and full-length enriched cDNA library from 5 ~ 30 days old immature seeds was constructed and randomly sequenced, leading to generation of 41,248 expressed sequence tags (ESTs) which then formed 4,713 contigs and 27,708 singletons with 44.9% uniESTs being putative full-length open reading frames. Approximately 26,091 of all these uniESTs have significant matches to the counterparts in Nr database of GenBank, and 21,628 of them were assigned to one or more Gene ontology (GO) terms. Homologous genes involved in oil biosynthesis were identified including some conservative transcription factors regulating oil biosynthesis such as LEAFY COTYLEDON1 (LEC1), PICKLE (PKL), WRINKLED1 (WRI1) and majority of them were found for the first time in sesame seeds. One hundred and 17 ESTs were identified possibly involved in biosynthesis of sesame lignans, sesamin and sesamolin. In total, 9,347 putative functional genes from developing seeds were identified, which accounts for one third of total genes in the sesame genome. Further analysis of the uniESTs identified 1,949 non-redundant simple sequence repeats (SSRs). Conclusions This study has provided an overview of genes expressed during sesame seed development. This collection of sesame full-length cDNAs covered a wide variety of genes in seeds, in particular, candidate genes involved in biosynthesis of sesame oils and lignans. These EST sequences enriched with full length will contribute to comparative genomic studies on sesame and other oilseed plants and serve as an abundant information platform for functional marker development and functional gene study.</p