Expression of wheat gibberellins 2-oxidase gene induced dwarf or semi-dwarf phenotype in rice

Gibberellins (GAs) are a class of plant hormones that play important roles in diverse aspects during plant growth and development. A series of GA synthesis and metabolism genes have been reported or proved to have essential functions in different plant species, while a small number of GA 2-oxidase genes have been cloned or reported in wheat. Previous studies have provided some important findings on the process of GA biosynthesis and the enzymes involved in its related pathways. These may facilitate understanding of the complicated process underlying GA synthesis and metabolism in wheat. In this study, GA 2-oxidase genes TaGA2ox1-1, TaGA2ox1-2, TaGA2ox1-3, TaGA2ox1-4, TaGA2ox1-5, and TaGA2ox1-6 were identified and further overexpressed in rice plants to investigate their functions in GA biosynthesis and signaling pathway. Results showed overexpression of GA 2-oxidase genes in rice disrupted the GA metabolic pathways and induced catalytic responses and regulated other GA biosynthesis and signaling pathway genes, which further leading to GA signaling disorders and diversity in phenotypic changes in rice plants

Sensitivity of deexcitation energies of superdeformed secondary minima to the density dependence of symmetry energy with the relativistic mean-field theory

The relationship between deexcitation energies of superdeformed secondary minima relative to ground states and the density dependence of the symmetry energy is investigated for heavy nuclei using the relativistic mean field (RMF) model. It is shown that the deexcitation energies of superdeformed secondary minima are sensitive to differences in the symmetry energy that are mimicked by the isoscalar-isovector coupling included in the model. With deliberate investigations on a few Hg isotopes that have data of deexcitation energies, we find that the description for the deexcitation energies can be improved due to the softening of the symmetry energy. Further, we have investigated deexcitation energies of odd-odd heavy nuclei that are nearly independent of pairing correlations, and have discussed the possible extraction of the constraint on the density dependence of the symmetry energy with the measurement of deexcitation energies of these nuclei.Comment: 14 pages, 3 figure

Study on the Failure Mechanism of the Polymorphic Mixture for Remanifactured Machinery Parts

The polymorphic mixture failure mode for multiple heterogeneity of remanifactured (RM) machinery parts makes it difficult to assess their lifetime. The Weibull distribution failure model of RM parts (substrate, coating layer, bonding surface and sudden failure) is constructed with failure time statistics of the parts in service, the latter is used to characterize the failure patterns of RM parts. In view of the multiple heterogeneity of RM parts, the Kaplan–Meier type decoupling method is used to analyze four sets of failure statistics, and each state of the Weibull failure function of the above parts is solved. It reveals the in-service failure mechanism of polymorphic mixtures for multiple heterogeneity of RM machinery parts. The validity and feasibility of the model are verified by the case study. Research results provide the theoretical basis for the design and preparation of a RM alloy powder and the improvement of RM technology. Moreover, the method for lifetime prediction and failure time evaluation of RM parts is proposed and validatedХарактер разрушения полиморфной смеси в условиях множественной гетерогенности модифицированных деталей затрудняет оценку срока службы оборудования. Модель разрушения распределения Вейбулла (разрушение подложки, наружного слоя, поверхости сцепления, мгновенное разрушение) построена на основании статистических данных о времени разрушения детелей в условиях эксплуатации. Использован метод разделения Каплана Мейера для анализа четырех множеств статистик разрушения, выполнено решение каждого состояния функции Вейбулла, что позволило установить механизм разрушения полиморфных смесей в условиях эксплуатации при множественной гетерогенности модифицированных деталей оборудования. На примере выполнения моделирования верифицированы достоверность и применимость модели. Создана теоретическая основа для разработки и изготовления порошка сплава и совершенствования технологии модифицирования. Разработан метод прогнозирования срока службы и оценки периода разрушения модифицированных деталей

Molecular Dynamics Study of Bamboo-like Carbon Nanotube Nucleation

MD simulations based on an empirical potential energy surface were used to study the nucleation of bamboo-like carbon nanotubes (BCNTs). The simulations reveal that inner walls of the bamboo structure start to nucleate at the junction between the outer nanotube wall and the catalyst particle. In agreement with experimental results, the simulations show that BCNTs nucleate at higher dissolved carbon concentrations (i.e., feedstock pressures) than those where non-bamboolike carbon nanotubes are nucleated

Review: Progress in the Studies on Mechanical Properties of Materials

Materials science and engineering is one of the hot research topics in the world, among which mechanical properties of materials play a critical role in application of the new materials. Based on this, a special session Mechanical Properties of Materials was held within the 2nd Global Conference on Materials Science and Engineering, Nov. 20–22, 2013. This special issue contains a selection of twenty scientific papers, which are focused on the structure, mechanical properties, and strength of materials. In this review, the selected papers from the special session are summarized.Материаловедение и инженерия относятся к наиболее актуальным направлениям научных исследований в мире, а применение новых материалов в значительной степени основывается на изучении механических свойств материалов. Исходя из этого в рамках 2-й Глобальной конференции по материаловедению и инженерии 20–22 ноября 2013 года была проведена специальная сессия по вопросам исследования механических свойств материалов. Этот специальный номер содержит подборку из 20 научных работ, отобранных из числа всех докладов, посвященных проблемам структуры, механических свойств и прочности материалов. В данном обзоре обсуждаются отдельные доклады специальной сессии, представленные в этом номере журнала.Матеріалознавство та інженерія відносяться до найбільш актуальних напрямків наукових досліджень у світі, тоді як використання нових матеріалів у значній мірі базується на дослідженні механічних властивостей матеріалів. Виходячи з цього, у межах 2-ї Глобальної конференції з матеріалознавства й інженерії 20–22 листопада 2013 року було проведено спеціальну сесію з питань дослідження механічних властивостей матеріалів. Цей спеціальний номер містить добірку з 20 наукових робіт,відібраних із числа всіх доповідей, присвячених проблемам структури, механічних властивостей і міцності матеріалів. У даному огляді обговорюються окремі доповіді спеціальної сесії, представлені в цьому номері журналу

Time-Dependent Partition-Free Approach in Resonant Tunneling Systems

An extended Keldysh formalism, well suited to properly take into account the initial correlations, is used in order to deal with the time-dependent current response of a resonant tunneling system. We use a \textit{partition-free} approach by Cini in which the whole system is in equilibrium before an external bias is switched on. No fictitious partitions are used. Besides the steady-state responses one can also calculate physical dynamical responses. In the noninteracting case we clarify under what circumstances a steady-state current develops and compare our result with the one obtained in the partitioned scheme. We prove a Theorem of asymptotic Equivalence between the two schemes for arbitrary time-dependent disturbances. We also show that the steady-state current is independent of the history of the external perturbation (Memory Loss Theorem). In the so called wide-band limit an analytic result for the time-dependent current is obtained. In the interacting case we propose an exact non-equilibrium Green function approach based on Time Dependent Density Functional Theory. The equations are no more difficult than an ordinary Mean Field treatment. We show how the scattering-state scheme by Lang follows from our formulation. An exact formula for the steady-state current of an arbitrary interacting resonant tunneling system is obtained. As an example the time-dependent current response is calculated in the Random Phase Approximation.Comment: final version, 18 pages, 9 figure

Controlling laser spectra in a phaseonium photonic crystal using maser

We study the control of quantum resonances in photonic crystals with electromagnetically induced transparency driven by microwave field. In addition to the control laser, the intensity and phase of the maser can alter the transmission and reflection spectra in interesting ways, producing hyperfine resonances through the combined effects of multiple scattering in the superstructure.Comment: 7 pages, 4 figure

Theoretical study of the two-proton halo candidate 17^{17}Ne including contributions from resonant continuum and pairing correlations

With the relativistic Coulomb wave function boundary condition, the energies, widths and wave functions of the single proton resonant orbitals for $^{17}$Ne are studied by the analytical continuation of the coupling constant (ACCC) approach within the framework of the relativistic mean field (RMF) theory. Pairing correlations and contributions from the single-particle resonant orbitals in the continuum are taken into consideration by the resonant Bardeen-Cooper-Schrieffer (BCS) approach, in which constant pairing strength is used. It can be seen that the fully self-consistent calculations with NL3 and NLSH effective interactions mostly agree with the latest experimental measurements, such as binding energies, matter radii, charge radii and densities. The energy of $\pi$2s$_{1/2}$ orbital is slightly higher than that of $\pi1d_{5/2}$ orbital, and the occupation probability of the $(\pi$2s$_{1/2})^2$ orbital is about 20%, which are in accordance with the shell model calculation and three-body model estimation

The [1,2] Pad\'e Amplitudes for ππ\pi\pi Scatterings in Chiral Perturbation Theory

A detailed analysis to the [1,2] Pad\'e approximation to the $\pi\pi$ scattering 2--loop amplitudes in chiral perturbation theory is made.Comment: Discussions expanded and references are added, version to appear in Physics Letters