11,794 research outputs found
Inference about Monophyly of the Family Oedipodidae and the Classification of Subfamilies Based on 16S rDNA Sequences
Most of grasshoppers in the family Oedipodidae are the famous agriculture pests in China. However monophyly and the relationships among the subfamilies within this family are unclear up to now. Here the phylogeny of the Oedipodidae was reconstructed based on 16S rDNA sequence fragments by using Mekongiella kingdoni and Atractomorpha sinensis as outgroups under weighted MP, NJ and Bayesian criteria. The 408 bp fragments of mitochondrial 16S rRNA gene were sequenced for 15 species from 4 subfamilies of the family Oedipodidae, and the homologous sequences of other 15 species of grasshoppers were downloaded from the GenBank data library. The numbers of transitions and transversions among pairwise comparisons of the 16S fragments were respectively plotted against percentage sequence differences. Saturation of transitions was discovered, and transversions were not saturated with the increase of percentage sequence difference in the plots. All the individuals of the Oedipodidae excluding Trilophidia annulata were gathered together in the three trees. Our results are very different from the traditionary taxonomy of the Oedipodidae including 4 subfamilies. The Bryodemellinae is not supported as a subfamily, and neither Locustinae nor Oedipodinae are supported as a monophyletic group in this study
Optimal Vibration Control for Half-Car Suspension on In-Vehicle Networks in Delta Domain
The paper explores the optimal vibration control design problem for a half-car suspension working on in-vehicle networks in delta domain. First, the original suspension system with ECU-actuator delay and sensor-ECU delay is modeled. By using delta operators, the original system is transformed into an associated sampled-data system with time delays in delta domain. After model transformation, the sampled-data system equation is reduced to one without actuator delays and convenient to calculate the states with nonintegral time delay. Therefore, the sampled-data optimal vibration control law can be easily obtained deriving from a Riccati equation and a Stein equation of delta domain. The feedforward control term and the control memory terms designed in the control law ensure the compensation for the effects produced by disturbance and actuator delay, respectively. Moreover, an observer is constructed to implement the physical realizability of the feedforward term and solve the immeasurability problem of some state variables. A half-car suspension model with delays is applied to simulate the responses through the designed controller. Simulation results illustrate the effectiveness of the proposed controller and the simplicity of the designing approach
Giα proteins exhibit functional differences in the activation of ERK1/2, Akt and mTORC1 by growth factors in normal and breast cancer cells
Background In a classic model, Giα proteins including Gi1α, Gi2α and Gi3α are important for transducing signals from Giα protein-coupled receptors (GiαPCRs) to their downstream cascades in response to hormones and neurotransmitters. Our previous study has suggested that Gi1α, Gi2α and Gi3α are also important for the activation of the PI3K/Akt/mTORC1 pathway by epidermal growth factor (EGF) and its family members. However, a genetic role of these Giα proteins in the activation of extracellular signal-regulated protein kinase 1 and 2 (ERK1/2) by EGF is largely unknown. Further, it is not clear whether these Giα proteins are also engaged in the activation of both the Akt/mTORC1 and ERK1/2 pathways by other growth factor family members. Additionally, a role of these Giα proteins in breast cancer remains to be elucidated. Results We found that Gi1/3 deficient MEFs with the low expression level of Gi2α showed defective ERK1/2 activation by EGFs, IGF-1 and insulin, and Akt and mTORC1 activation by EGFs and FGFs. Gi1/2/3 knockdown breast cancer cells exhibited a similar defect in the activations and a defect in in vitro growth and invasion. The Giα proteins associated with RTKs, Gab1, FRS2 and Shp2 in breast cancer cells and their ablation impaired Gab1’s interactions with Shp2 in response to EGF and IGF-1, or with FRS2 and Grb2 in response to bFGF. Conclusions Giα proteins differentially regulate the activation of Akt, mTORC1 and ERK1/2 by different families of growth factors. Giα proteins are important for breast cancer cell growth and invasion.Fil: Wang, Zhanwei. University of Hawaii Cancer Center. Honolulu; Estados UnidosFil: Dela Cruz, Rica. University of Hawaii Cancer Center. Honolulu; Estados UnidosFil: Ji, Fang. Shanghai Jiao Tong University . Sahnghai; ChinaFil: Guo, Sheng. University of Hawaii Cancer Center. Honolulu; Estados Unidos. Shanghai Jiaotong University. Shangha; Estados UnidosFil: Zhang, Jianhua. Shanghai Jiaotong University. Shangha; Estados Unidos. University of Hawaii Cancer Center. Honolulu; Estados UnidosFil: Wang, Ying. David Geffen School of Medicine at UCLA. Los Angeles; Estados UnidosFil: Feng, Gen-Sheng. University of California at San Diego; Estados UnidosFil: Birnbaumer, Lutz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. National Institutes of Health; Estados UnidosFil: Jiang, Meisheng. David Geffen School of Medicine at UCLA. Los Angeles; Estados UnidosFil: Chu, Wen Ming. University of Hawaii Cancer Center. Honolulu; Estados Unido
Improving mobility of silicon metal-oxide-semiconductor devices for quantum dots by high vacuum activation annealing
To improve mobility of fabricated silicon metal-oxide-semiconductor (MOS)
quantum devices, forming gas annealing is a common method used to mitigate the
effects of disorder at the Si/SiO2 interface. However, the importance of
activation annealing is usually ignored. Here, we show that a high vacuum
environment for implantation activation is beneficial for improving mobility
compared to nitrogen atmosphere. Low-temperature transport measurements of Hall
bars show that peak mobility can be improved by a factor of two, reaching 1.5
m^2/(Vs) using high vacuum annealing during implantation activation. Moreover,
the charge stability diagram of a single quantum dot is mapped, with no visible
disturbance caused by disorder, suggesting possibility of fabricating
high-quality quantum dots on commercial wafers. Our results may provide
valuable insights into device optimization in silicon-based quantum computing.Comment: 13 pages, 4 figure
2,5-Bis(9H-carbazol-9-yl)thiophene
The molecules of the title compound, C28H18N2S, are built up from two triply-fused rings and one five-membered ring, with dihedral angles of 66.12 (8) and 70.96 (7)° between the central thiophene ring and the two triply-fused rings
Study of the 3D Coronal Magnetic Field of Active Region 11117 Around the Time of a Confined Flare Using a Data-Driven CESE--MHD Model
We apply a data-driven MHD model to investigate the three-dimensional (3D)
magnetic field of NOAA active region (AR) 11117 around the time of a C-class
confined flare occurred on 2010 October 25. The MHD model, based on the
spacetime conservation-element and solution-element (CESE) scheme, is designed
to focus on the magnetic-field evolution and to consider a simplified solar
atomsphere with finite plasma . Magnetic vector-field data derived from
the observations at the photoshpere is inputted directly to constrain the
model. Assuming that the dynamic evolution of the coronal magnetic field can be
approximated by successive equilibria, we solve a time sequence of MHD
equilibria basing on a set of vector magnetograms for AR 11117 taken by the
Helioseismic and Magnetic Imager (HMI) on board the {\it Solar Dynamic
Observatory (SDO)} around the time of flare. The model qualitatively reproduces
the basic structures of the 3D magnetic field, as supported by the visual
similarity between the field lines and the coronal loops observed by the
Atmospheric Imaging Assembly (AIA), which shows that the coronal field can
indeed be well characterized by the MHD equilibrium in most time. The magnetic
configuration changes very limited during the studied time interval of two
hours. A topological analysis reveals that the small flare is correlated with a
bald patch (BP, where the magnetic field is tangent to the photoshpere),
suggesting that the energy release of the flare can be understood by magnetic
reconnection associated with the BP separatrices. The total magnetic flux and
energy keep increasing slightly in spite of the flare, while the computed
magnetic free energy drops during the flare with an amount of
erg, which seems to be adequate to provide the energy budget of the minor
C-class confined flare.Comment: 27 pages, 11 figures, Accepted by Ap
Mutations in an AP2 Transcription Factor-Like Gene Affect Internode Length and Leaf Shape in Maize
Background
Plant height is an important agronomic trait that affects yield and tolerance to certain abiotic stresses. Understanding the genetic control of plant height is important for elucidating the regulation of maize development and has practical implications for trait improvement in plant breeding.
Methodology/Principal Findings
In this study, two independent, semi-dwarf maize EMS mutants, referred to as dwarf & irregular leaf (dil1), were isolated and confirmed to be allelic. In comparison to wild type plants, the mutant plants have shorter internodes, shorter, wider and wrinkled leaves, as well as smaller leaf angles. Cytological analysis indicated that the leaf epidermal cells and internode parenchyma cells are irregular in shape and are arranged in a more random fashion, and the mutants have disrupted leaf epidermal patterning. In addition, parenchyma cells in the dil1 mutants are significantly smaller than those in wild-type plants. The dil1 mutation was mapped on the long arm of chromosome 6 and a candidate gene, annotated as an AP2 transcription factor-like, was identified through positional cloning. Point mutations near exon-intron junctions were identified in both dil1 alleles, resulting in mis-spliced variants.
Conclusion
An AP2 transcription factor-like gene involved in stalk and leaf development in maize has been identified. Mutations near exon-intron junctions of the AP2 gene give mis-spliced transcript variants, which result in shorter internodes and wrinkled leaves
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