Electrical energy storage plays a key role in mobile electronic devices, stationary power systems, and hybrid electric vehicles. [1][2][3] There is a great need for development of new materials with superior electrical energy density since current ceramics and polymers fall significantly short of rising demands in advanced applications. The introduction of inorganic nanoparticles into polymer matrices to form dielectric polymer nanocomposites represents one of the most promising and exciting avenues to this end. [4][5][6][7][8][9][10][11] This approach is motivated by the idea that the combination of ceramic materials of large permittivity with polymers of high breakdown strength could lead to a large energy storage capacity, as energy density is proportional to the product of permittivity and the square of the applied electric field. Moreover, large interfacial areas in the composites containing nanometer scale fillers promote the exchange coupling effect through a dipolar interface layer and result in higher polarization levels and dielectric responses. [12,13] Compared to conventional ceramic materials, polymer-based dielectric materials also offer processing advantages including mechanical flexibility and the ability to be molded into intricate configurations for electronic and electric devices with reduced volume and weight. While most of the current studies on dielectric nanocomposites are focused on the enhancement of dielectric permittivity, few examples have investigated dielectric properties and associated energy densities at high electric fields. [14][15][16] Ferroelectric metal oxides such as Pb(Zr,Ti)O 3 (PZT), Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 (PMNT), and BaTiO 3 have been popular choices as filler materials in dielectric nanocomposites because of their high permittivities. However, from the energy storage point of view, inclusion of nanoparticles with permittivities on the order of hundreds and even thousands into polymers, which generally possess a permittivity less than 10, might not be desirable for an appreciable increase in energy density. As the filler has a much greater permittivity than the polymer matrix, most of the increase in effective dielectric permittivity comes though an increase in the average field in the polymer matrix with very little of the energy being stored in the high permittivity filler phase.[17] Furthermore, the presence of a large contrast in permittivity between two phases gives rise to a highly inhomogeneous electric field and thus a significantly reduced effective breakdown strength of the composite. [18] In this communication, we report high-energy-density polymer nanocomposites based on surface-functionalized TiO 2 nanocrystals as dopants in a ferroelectric poly(vinylidene fluoride-tertrifluoroethylene-ter-chlorotrifluoroethylene) (P(VDF-TrFE-CTFE)). In this approach, the polymer matrix and TiO 2 filler possess comparable dielectric permittivities of 42 and 47, respectively, measured using an inductance, capacitance, resistance (LCR) meter at room temperature and 1 kH...

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Correct positioning of the mitotic spindle is critical for cell division and development. Spindle positioning involves a search-and-capture mechanism whereby dynamic microtubules find and then interact with specific sites on the submembrane cortex. Genetic, biochemical, and imaging experiments suggest a mechanism for cortical-microtubule capture. Bim1p, located at microtubule distal ends, bound Kar9p, a protein associated with the daughter cell cortex. Bim1p is the yeast ortholog of human EB1, a binding partner for the adenomatous polyposis coli tumor suppressor. EB1 family proteins may have a general role in linking the microtubule cytoskeleton to cortical polarity determinants.

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BackgroundCancer stem cells (CSCs) or tumor-initiating cells (TICs) represent a small population of cancer cells with self-renewal and tumor-initiating properties. Unlike the bulk of tumor cells, CSCs or TICs are refractory to traditional therapy and are responsible for relapse or disease recurrence in cancer patients. Stem cells have distinct metabolic properties compared to differentiated cells, and metabolic rewiring contributes to self-renewal and stemness maintenance in CSCs.Main bodyRecent advances in metabolomic detection, particularly in hyperspectral-stimulated raman scattering microscopy, have expanded our knowledge of the contribution of lipid metabolism to the generation and maintenance of CSCs. Alterations in lipid uptake, de novo lipogenesis, lipid droplets, lipid desaturation, and fatty acid oxidation are all clearly implicated in CSCs regulation. Alterations on lipid metabolism not only satisfies the energy demands and biomass production of CSCs, but also contributes to the activation of several important oncogenic signaling pathways, including Wnt/β-catenin and Hippo/YAP signaling. In this review, we summarize the current progress in this attractive field and describe some recent therapeutic agents specifically targeting CSCs based on their modulation of lipid metabolism.ConclusionIncreased reliance on lipid metabolism makes it a promising therapeutic strategy to eliminate CSCs. Targeting key players of fatty acids metabolism shows promising to anti-CSCs and tumor prevention effects.

A polymer triple-shape memory effect represents one of the most recent discoveries in the rapidly expanding field of shape memory polymers. It refers to the capability of a polymer to memorize two temporary shapes and subsequently recover them, all in one shape memory cycle. Although several examples of triple-shape polymers had been reported in the literature, they were notably evaluated under very different thermo-mechanical conditions. In this study, the effect of various thermo-mechanical conditions on the polymer triple-shape properties was investigated using Nafion as a model material. The choice of the programming and recovery heating methods in constructing triple-shape cycles was found to have a profound impact on the triple-shape properties. As such, the results of this study provided useful reference for future development of triple-shape polymers.

BackgroundCurrently there exists a limited availability of genetic marker resources in sweetpotato (Ipomoea batatas), which is hindering genetic research in this species. It is necessary to develop more molecular markers for potential use in sweetpotato genetic research. With the newly developed next generation sequencing technology, large amount of transcribed sequences of sweetpotato have been generated and are available for identifying SSR markers by data mining.ResultsIn this study, we investigated 181,615 ESTs for the identification and development of SSR markers. In total, 8,294 SSRs were identified from 7,163 SSR-containing unique ESTs. On an average, one SSR was found per 7.1 kb of EST sequence with tri-nucleotide motifs (42.9%) being the most abundant followed by di- (41.2%), tetra- (9.2%), penta- (3.7%) and hexa-nucleotide (3.1%) repeat types. The top five motifs included AG/CT (26.9%), AAG/CTT (13.5%), AT/TA (10.6%), CCG/CGG (5.8%) and AAT/ATT (4.5%). After removing possible duplicate of published EST-SSRs of sweetpotato, a total of non-repeat 7,958 SSR motifs were identified. Based on these SSR-containing sequences, 1,060 pairs of high-quality SSR primers were designed and used for validation of the amplification and assessment of the polymorphism between two parents of one mapping population (E Shu 3 Hao and Guang 2k-30) and eight accessions of cultivated sweetpotatoes. The results showed that 816 primer pairs could yield reproducible and strong amplification products, of which 195 (23.9%) and 342 (41.9%) primer pairs exhibited polymorphism between E Shu 3 Hao and Guang 2k-30 and among the 8 cultivated sweetpotatoes, respectively.ConclusionThis study gives an insight into the frequency, type and distribution of sweetpotato EST-SSRs and demonstrates successful development of EST-SSR markers in cultivated sweetpotato. These EST-SSR markers could enrich the current resource of molecular markers for the sweetpotato community and would be useful for qualitative and quantitative trait mapping, marker-assisted selection, evolution and genetic diversity studies in cultivated sweetpotato and related Ipomoea species.

Surface wrinkles are created on a metallic film supported on a shape memory polymer substrate. The wrinkle wavelength approaches that of visible lights, resulting in diffraction colors. The spatial and geometric distribution of the surface wrinkles can be controlled in an arbitrary fashion, allowing the capture of a three dimensional arbitrary image on a macroscopically flat surface.