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Self-incompatibility (SI) is a mechanism used to prevent inbreeding and promote outcrossing in a wide variety of angiosperms. Camellia oleifera (Theaceae), is one of the most prominent wood oil plants. However, self-incompatibility results in a relatively low ratio of fruit/seed sets to flowers in C. oleifera. In this study, fluorescence microscopy and confocal microscopy were used to observe how pollen tube growth differed between cross- vs. self-pollination events. We found that self-pollen tubes appear twisted and clustered when growing to the base of the style and it is impossible for self-pollen tubes to reach the embryo sac to complete double fertilization. In contrast, pollen tubes from crossing events grow normally and reach the ovary to complete fertilization. We characterised candidate genes related to SI and investigated the underlying mechanisms regulating fertilization by performing RNA-seq on C. oleifera. In addition, we also conducted qRT-PCR on 20 unigenes to validate our RNA-seq data. We identified genes encoding protein kinases and phosphatases, Ca2+ signaling proteins, transcription factors, CYP family members, and defense-related proteins as candidate genes related to SI in C. oleifera. With these genes identified, more thorough studies of SI mechanisms in C. oleifera have become possible. [ABSTRACT FROM AUTHOR]

A kind of paraffin@graphene/silicone rubber (SR) composite form-stable phase change material (PCM) was prepared in this paper. Paraffin@graphene phase change microcapsules were fabricated by electrostatic self-assembly method, then the microcapsules were added to the SR matrix to prepare paraffin@graphene/SR composites. The microstructure of the composite was characterized by scanning electron microscopy (SEM). Differential scanning calorimetry (DSC) and thermal conductivity test results show that the phase change latent heat is 53.39 J g−1 and the thermal conductivity reaches 0.453 W m−1 K−1 for the composite with 30 phr paraffin@graphene microcapsules. The microcapsules enhance the thermal and mechanical properties of SR, which can be used for thermal energy storage. [ABSTRACT FROM AUTHOR]

A novel kind of paraffin-based shape-stable phase change materials (SSPCMs) was prepared by introducing paraffin into reduced graphene oxide (rGO)/carbon nanotubes (CNTs) aerogel via vacuum-assisted impregnation method. The effects of ratio of rGO to CNTs in 3D network structure on morphology, structure and property of paraffin-based SSPCMs were investigated. The rGO/CNTs 3D network structure with high thermal conductivity, served as thermally conductive skeleton together. In particular, CNTs was used as a secondary heat conductive filler, which could be well dispered in the SSPCMs to conduct heat synergistically. The SSPCMs exhibited high thermal conductivity and excellent shape-stability. And the thermal conductivity of SSPCMs can be regulated by adjusting the ratio of rGO to CNTs in aerogels. These results indicate that 3D rGO/CNTs aerogels have advantages as thermally conductive skeleton, and can endow phase transition materials with stable shape, so as to realize the application of phase change materials in the field of heat dissipation. [ABSTRACT FROM AUTHOR]

Thermally conductive and electrically insulating h-BN/MVQ and h-BN/SiCw/MVQ composites were prepared by internal mixing and two roll mixing, using 1-dimensional (1D) silicon carbide whiskers (SiCw) and 2-dimensional (2D) hexagonal boron nitride flakes (h-BN) as fillers, and methyl vinyl silicone rubber (MVQ) as polymer matrix. Surface modification of 1 D SiCw and 2 D h-BN was characterized by Fourier transform infrared spectroscopy (FT-IR) and contact angle analysis. Morphology, thermal conductivity and dielectric constant of h-BN/MVQ and h-BN/SiCw/MVQ were studied. The results indicated that surface modified h-BN and SiCw could be uniformly distributed in MVQ matrix. At the same volume filler loading, thermal conductivity of h-BN/SiCw/MVQ ternary composite was higher than that of h-BN/MVQ binary composite. When part of 2 D h-BN was instead of 1 D SiCw, there was synergistically enhanced effect between 1 D SiCw and 2 D h-BN for thermal conductivity. When volume ratio of h-BN/SiCw was 8/2, thermal conductivity of h-BN/SiCw/MVQ was higher than that of other ratio. Thermal conductivity of h-BN/SiCw/MVQ composite with different volume ratio was linearly fit with Agari' model. [ABSTRACT FROM AUTHOR]

A kind of shape-stable phase change materials (SSPCMs) was prepared by using graphene aerogel (GA) with different pore size adsorbing molten paraffin wax via vacuum impregnation. The characteristics of SSPCMs were determined by scanning electron microscopy (SEM), X-ray diffractometer (XRD), differential scanning calorimetry (DSC) and TCi thermal conductivity analyzer. The SSPCMs possessed a high comprehensive performance: a high thermal conductivity of 1.432 W/m·K (more than 400% increase over pure paraffin), a good capacity of thermal energy storage (more than 200 J/g), a ability to light-to-heat energy storage and coating effect (encapsulation ratio is about 55%) due to the three-dimensional GA foam structure with functions of thermal conductivity and adsorptive property. In addition, an energy conversion from light to heat was realized with the SSPCMs. For different morphologies of GA, as pore size of GA decreases, SSPCMs' thermal conductivity and solar energy usage efficiency increases and their leakage rate reduces. This means that pore size of GA can influence the properties of SSPCMs to some extent. [ABSTRACT FROM AUTHOR]

Surfactant can be used to form stable oil-in-water emulsion and reduce the viscosity of viscous crude oil. The mechanism of viscosity reduction was studied for nonionic surfactant alkylphenol polyoxyethylene (9) ether (APE-9) compound systems. The results showed that the viscosity reduction of viscous crude oil by water-insoluble alkylphenol polyoxyethylene (4) ether (APE-4) was higher than sodium dodecyl sulfate (SDS, anionic surfactant) and dodecyl dimethyl betaine (BS-12, amphoteric surfactant) in the binary compound system. The viscosity further decreased by ethanolamine. The interfacial tension (IFT) study showed that when the reduction in IFT was the highest, the viscosity reduction was the highest. [ABSTRACT FROM AUTHOR]

Research shows that the viscosity greatly reduction of viscous crude oil can improve the exploitation and promote the fluidity. We studied the effects and the mechanism of viscosity reduction of viscous crude oil emulsion after introducing the ternary compound of sulfonate-straight chain alcohol-alkaline as the viscosity reducer. Results showed that the best emulsifying performance can be achieved using 5% 1-pentanol. 0.2% of Na2CO3 and DEA shows the strongest emulsification ability of the O/W emulsion. The use of AOS, straight chain alcohol and petroleum carboxylate resolves diffusion on the oil-water interface, which can form a dense surfactant of single molecular layer to reduce the interfacial tension and prevent the phase change of the emulsification. When the mass fraction of AOS, Na2CO3, DEA and 1-pentanol were 0.2%, 0.25%, 0.2% and 5% respectively, the viscous crude oil would achieve the best effect of viscosity reduction. [ABSTRACT FROM AUTHOR]

In this article, we fabricated a bioactive hydrogel composed of glycol chitosan (G-CS) and oxidized hyaluronic acid (OHA) via Schiff base reaction. Cartilage extracellular matrix (ECM) particles with different concentrations were used to functionalize G-CS/OHA (S1) hydrogel. The results demonstrated that S3 (G-CS/OHA/ECM 2% w/v) hydrogel exhibited the most suitable compression strength and provided the optimal environment for proliferation of bone marrow mesenchymal stem cells (BMSCs). To assess the chondroinductivity of ECM in vitro, we compared the chondrogenesis of BMSCs in S1 (G-CS/OHA) and S3 (G-CS/OHA/ECM 2% w/v) hydrogels. The results confirmed that the higher levels of glycosaminoglycans (GAGs) and collagen type II (COL II) were accumulated in S3 hydrogel. In vivo, cartilage defects of rats generated most mature tissue within BMSCs-laden S3 hydrogel (S3/BMSCs group). The tissues were more integrative and contained higher levels of COL II and GAGs compared to the other groups. All these results suggested that the G-CS/OHA hydrogel functionalized with ECM particles is a good candidate biomaterial to be applied in cartilage tissue engineering. [ABSTRACT FROM AUTHOR]

Cyclic tests and finite-element method (FEM) analyses were used to study the effects of varying the type of pile, stirrup ratio and reinforcement technique—concrete infilling, steel fibers or deformed steel bars—on the seismic performance of prestressed high-strength concrete (PHC) piles. The failure modes, hysteretic performance, ductility, bearing capacity, stiffness degradation and energy dissipation capacity were observed and analyzed. The results show that the PHC piles were damaged by bending, and that the bearing capacity and ductility of the PHC piles increases with the reinforcement ratio of the prestressed tendons. It was found that adding concrete infilling into the hollow section improves the bearing capacity and hysteretic performance of the PHC piles, whereas the steel fibers have little effect. It was also found that the hysteretic loops of the PHC piles reinforced with deformed steel bars are fuller, and that the energy dissipation is good. An FEM analysis was used to simulate the nonlinear behavior of the PHC piles under cyclic loading, and the predictions agree relatively well with the experimental results. [ABSTRACT FROM AUTHOR]

Conclusion: This study demonstrates that the gap junction protein beta-2 gene (GJB2) p.R32C and p.L79Cfs*3 variants are associated to a consanguineous family with autosomal recessive non-syndromic hearing loss (ARNSHL). The p.R32C variant is found for the first time in the NSHL patients of Han Chinese origin. The finding sheds new light on the accurate genetic diagnosis and counseling for the family.Objective: ARNSHL is a highly heterogeneous genetic disease. ARNSHL usually displays non-progressive congenital or pre-lingual deafness. In this study, the aim is to detect the disease-causing mutation(s) in a Han family with ARNSHL.Methods: A consanguineous Han family with ARNSHL was enrolled. Two hundred ethnicity-matched unrelated subjects without any hearing impairments were used as normal controls. Exome sequencing and Sanger sequencing were applied to identify the causative mutation in the ARNSHL family.Results: Compound heterozygous variants c.94C > T (p.R32C) and c.235delC (p.L79Cfs*3) in theGJB2gene were identified in the two patients of the ARNSHL family, and the heterozygousGJB2c.94C > T and c.235delC variants were identified in his unaffected father and mother, respectively. The two variants in theGJB2gene were absent in the 200 unrelated controls. [ABSTRACT FROM PUBLISHER]

Objective: The purpose of this work was to prepare a stable paclitaxel nanosuspension and test it for potential use as a targeted chemotherapeutic. Different particle coatings were employed to assess their impact on cellular uptake in vitro. In vivo work was then performed to demonstrate efficacy in tumor-bearing mouse models. Materials and method: Paclitaxel nanosuspensions were prepared using a homogenization process and coated with excipients. Surface charge was measured by zeta potential, potency by high-performance liquid chromatography, and solubility using an in-line UV probe. Cellular uptake studies were performed via flow cytometry. In vivo experiments were performed to determine residence time, maximum tolerated dose, and the efficacy of paclitaxel nanosuspensions (Paclitaxel-NS). Results: A stable paclitaxel nanosuspension was prepared and coated with various excipients. Studies in mice showed that the nanosuspension was well-tolerated and at least as effective as the IV Taxol control in prolonging mouse survival in a head and neck cancer model as well as an ovarian cancer model with a lower overall drug dose than the traditional IV administration route. Conclusions: The paclitaxel nanosuspension is suitable for cellular uptake. The nanosuspension was effective in prolonging life in two separate xenograft orthotopic murine cancer models through two separate routes of administration. [ABSTRACT FROM AUTHOR]

The chemical form and subcellular and molecular distribution of cadmium (Cd) in the roots and leaves was investigated in two rice genotypes: the low Cd-accumulating ‘‘Guangyuanzhan No. 3’, and the high Cd-accumulating ‘‘Zhenguiai.’’ Elevated Cd level in the medium caused a significant increase in Cd concentration in all parts of the roots and leaves. The soluble fractions in leaves and roots of ‘Zhenguiai’ contained a higher proportion of the Cd than those in ‘Guangyuanzhan No. 3’. Furthermore, ‘Zhenguiai’ had a higher proportion of de-ionized water and 80% ethanol-extractable Cd, which is the most mobile Cd among its various chemical forms. Following gel filtration of the soluble fraction of leaf and root extracts of both genotypes, a compound with a molecular weight of ∼3 kDa, probably comprising phytochelatins (PCs), was the major Cd-binding component. The Cd concentrations in the fractions from the roots of ‘Zhenguiai’ were noticeably higher than those of ‘Guangyuanzhan No. 3’, which possibly resulted in the latter cultivar having a lower Cd mobility in the roots and less Cd translocation from the roots to the aboveground parts. [ABSTRACT FROM PUBLISHER]