Stabilizing high-voltage LCO cycling is a hot topic in both academic and industrial research. [3,4] However, the exact mechanism that caused the quick fading of high-voltage LCO has not yet reached consensus. [5,6] The band energy diagram in Figure S1 in the Supporting Information shows that cycling LCO to high voltage must entail a hybrid O anion (O 2− →O α− , α < 2) and Co cation-redox (HACR). [7,8] It is tempting to "exploit" HACR in LCO for much higher capacity, e.g., if LCO is charged to above 4.6 V, more than 220 mAh g −1 can be obtained; however, because of the reduced ionic radius and electrostatic force, the oxidized O α− would become much mobile [9] and more likely to escape from the particle, resulting in oxygen loss (OL). Continuous OL can be a killer problem to high-voltage cycling. [10] First, OL causes irreversible phase transformations (CoO 2 →Co 3 O 4) [11] (Figure S2, Supporting As the pioneer cathode for rechargeable Li-ion battery, [1] LiCoO 2 (LCO) is still dominating today's battery markets in consumer electronic devices, due to its high volumetric energy density and stable cycling. However, as LCO is only cycled within 4.35 V and 165 mAh g −1 at the present to meet the industrial-level cycling life, [2] there is still a large space to increase its utilizable capacity by charging LCO to higher voltages before it reaches

Summary• Sequencing of the Populus trichocarpa genome creates an opportunity to describe the transcriptome of a woody perennial species and establish an atlas of gene expression. A comparison with the transcriptomes of other species can also define genes that are conserved or diverging in plant species.• Here, the transcriptome in vegetative organs of the P. trichocarpa reference genotype Nisqually-1 was characterized. A comparison with Arabidopsis thaliana orthologs was used to distinguish gene functional categories that may be evolving differently in a woody perennial and an annual herbaceous species.• A core set of genes expressed in common among vegetative organs was detected, as well as organ-specific genes. Statistical tests identified chromatin domains, where adjacent genes were expressed more frequently than expected by chance. Extensive divergence was detected in the expression patterns of A. thaliana and P. trichocarpa orthologs, but transcription of a small number of genes appeared to have remained conserved in the two species.• Despite separation of lineages for over 100 million yr, these results suggest that selection has limited transcriptional divergence of genes associated with some essential functions in A. thaliana and P. trichocarpa. However, extensive remodeling of transcriptional networks indicates that expression regulation may be a key determinant of plant diversity.

Understanding how an organism develops into a fully functioning adult from a mass of undifferentiated cells may reveal different strategies that allow the organism to survive under limiting conditions. Here, we review an analytical model for characterizing quantitative trait loci (QTLs) that underlie variation in growth trajectories and developmental timing. This model, called functional mapping, incorporates fundamental principles behind biological processes or networks that are bridged with mathematical functions into a statistical mapping framework. Functional mapping estimates parameters that determine the shape and function of a particular biological process, thus providing a flexible platform to test biologically meaningful hypotheses regarding the complex relationships between gene action and development.

In this paper, dielectric columns with different dielectric constants are employed as dielectric materials in the packed bed reactor to investigate the dynamic behaviors of plasma interaction processes. The effects of the dielectric constants (zirconia: ε = 25 and PTFE: ε = 2.5) on the production of reactive species are studied for plasma catalysis applications. Comparison studies of discharge images, electrical characteristics, discharge dynamic evolution and spatial-temporal resolved optical emission spectroscopy are carried on when zirconia and PTFE columns are employed. The results show that there are four discharge processes existing in the packed bed reactor: surface streamer on the dielectric column, local discharge at the contact point, surface discharge on the grounded dielectric plate, and the volume discharge. The production of reactive species such as N 2 (C 3 Π u ), N + 2 (B 2 Σ + u ) and O(3p 5 P) depend on the discharge processes to a great extent. The production of the N + 2 (B 2 Σ + u ) always accompanies the formation of the streamer by electrons direct impact process to excite the ground state nitrogen molecules to N + 2 (B 2 Σ + u ). The O(3p 5 P) is generated in two different ways, which plays a major role during the voltage pulse raising and falling time, respectively. The rst way is the direct and fast one-step ionization and excitation by high energy electrons with O 2 . The second way is the energy transfer from the nitrogen metastable N 2 (A 3 Σ + u ) and energetic electrons, in which the O is rst ionized from O 2 and then excited to O(3p 5 P). Furthermore, compared with a zirconia column, a PTFE column is more conductive to the generation of reactive species.

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In the nervous system, ion channels are essential for all processes. The highly ordered porous anodic aluminum oxide (AAO) was modified at the interface between two immiscible electrolyte solutions (ITIES) to recover the process of ion transfer through the ion channels. The study on dynamic process of ion transfer through the ion channels obtained for D K + 0 is 1.40 × 10−8 cm2 s−1 and D Na+ 0 is 2.74 × 10−7 cm2 s−1. The result offers tremendous advantages for linear relationship between the half-wave potential and concentration of K+ and Na+. In addition, it will be helpful to understand both the mechanism about the dynamics and thermodynamics processes of ion transfer through the ion channels and the role about ionic concentration in nerve conduction.

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Two kinds of polyimides (PIs) were selected as matrices for multiwalled carbon nanotubes (CNTs)-based nanocomposites. The two PIs were initially synthesized through reactions of a same benzoxazole-containing diamine with two different dianhydrids. A linear PI was formed from the ether bond-containing dianhydride, while a nonlinear PI was formed from the AC(CF3) 22 groups containing dianhydride. Optimized dispersion of nanotubes in both kinds of PIs was found to be at a concentration with 0.5 wt % COOH-CNT, where great enhancement was achieved for both PIs. It was also found that introducing nanotubes into PI matrices aroused more significant increase of Young's modulus and break stress in linear PI than that in nonlinear PI. To determine the key parameters involved in design of PIs for maximum reinforcement efficiency using CNT as the nanofiller, the nanoscopic dispersion state of the nanotubes in diamine solution and their reaction were investigated via morphological and spectroscopic studies. The interfacial interactions between nanotubes and two PI chains were characterized by FT-IR and Raman spectroscopy. The fracture surface characteristics of two series of CNT/PI nanocomposites were further investigated using SEM. Our findings show that the diamine plays a double role for the in-situ polymerization, a dispersant to disentangle the CNT agglomerates and a monomer for PI synthesis with dianhydrides. It was also found that geometry and flexibility of PI chains are crucial to determine the interfacial interactions between nanotubes and PI chains. For elucidating the different interfacial characteristics of the two PIs on the surface of CNT, we proposed a model for preferred conformation adopted by a single PI chain on a single CNT. V C 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40479.