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The fabrication of multi-material medical phantoms with both patient-specificity and realistic mechanical properties is of great importance for the development of surgical planning and medical training. In this work, a 3D multi-material printing system for medical phantom manufacturing was developed. Rigid and elastomeric materials are firstly combined in such application for an accurate tactile feedback. The phantom is designed with multiple layers, where silicone ink, Thermoplastic Polyurethane (TPU), and Acrylonitrile Butadiene Styrene (ABS) were chosen as printing materials for skin, soft tissue, and bone, respectively. Then, the printed phantoms were utilized for the investigation of needle-phantom interaction by needle insertion experiments. The mechanical needle-phantom interaction was characterized by skin-soft tissue interfacial puncture force, puncture depth, and number of insertion force peaks. The experiments demonstrated that the manufacturing conditions, i.e. the silicone grease ratio, interfacial thickness and the infill rate, played effective roles in regulating mechanical needle-phantom interaction. Moreover, the influences of material properties, including interfacial thickness and ultimate stress, on needle-phantom interaction were studied by finite element simulation. Also, a patient-specific forearm phantom was printed, where the anatomical features were acquired from Computed Tomography (CT) data. This study provided a potential manufacturing method for multi-material medical phantoms with tunable mechanical properties and offered guidelines for better phantom design.

Indoleacetic acid (IAA)-carbendazim was synthesized to assess whether this conjugate could retain the fungicidal activity of carbendazim and gain root-inducing properties upon the addition of an indoleacetic acid group. An indoor virulence test demonstrated that the conjugate retained the fungicidal activity of carbendazim towards Cylindrocladium parasiticum. The conjugate was detected in roots after soaking Ricinus communis L. leaves into a solution of the IAA-carbendazim, which confirmed its phloem mobility. The activities of the cellulase, polygalacturonase and xylanase produced by Cylindrocladium parasiticum treated with different concentrations of the conjugate were determined, and the peak activities appeared at 72 h or 96 h. More importantly, the conjugate showed the ability to promote root growth. These results revealed that indoleacetic acid-carbendazim may be useful in preventing Cylindrocladium parasiticum and other diseases.

In this paper, we demonstrated large-size free-standing single-crystal β-Ga2O3 NMs fabricated by the hydrogen implantation and lift-off process directly from MOCVD grown β-Ga2O3 epifilms on native substrates. The optimum implantation conditions were simulated with a Monte-Carlo simulation method to obtain a high hydrogen concentration with a narrow ion distribution at the desired depth. Two as grown β-Ga2O3 samples with different orientations ([100] and [001]) were used to successfully create 1.2 μm thick β-Ga2O3 NMs without any physical damage. These β-Ga2O3 NMs were then transfer-printed onto rigid and flexible substrates such as SiC and polyimide substrates. Various material characterization studies were performed to investigate their crystal quality, surface morphologies, optical properties, mechanical properties, and bandgaps before and after the lift-off and revealed that the good material quality was maintained. This result offers several benefits in that the thickness, doping, and size of β-Ga2O3 NMs can be fully controlled. Moreover, more advanced β-Ga2O3-based NM structures such as (AlxGa1−x)2O3/Ga2O3 heterostructure NMs can be directly created from their bulk epitaxy substrates; thus this study provides a viable route for the realization of high performance β-Ga2O3 NM-based electronics and optoelectronics that can be built on various substrates and platforms.

Multi-material fused deposition modeling (FDM) is an effective tool to realize the optimal design and manufacturing with various materials, but how to achieve an adequate level of interfacial bonding strength between dissimilar materials is still a critical problem. Herein, the influence of three multi-material FDM processing parameters, i.e. nozzle temperature, building stage temperature and printing speed, on the interfacial bonding strength of thermoplastic polyurethane (TPU)/acrylonitrile butadiene styrene (ABS) bi-material structures was experimentally investigated. It was found that the interfacial bonding strength was significantly improved from 0.86 to 1.66 MPa (increased by 93%) when the building stage temperature increased from 30 to 68 °C, which was the most effective processing parameter. Then, a heat transfer-based polymer inter-molecular diffusion theory was developed to understand the interfacial bonding mechanism. The interfacial temperature profiles during multi-material FDM process were experimentally measured by inserting thermocouples into printing specimens, and the theoretical model was well validated due to the good agreement between experimental and numerical data of interfacial temperature and bonding strength. The model provided an accurate prediction of interfacial bonding strength based on the understanding of thermally-driven diffusion of multi-material filaments; which would help improving the mechanical properties of products fabricated by multi-material FDM. Keywords: Multi-material fused deposition modeling, Bonding strength, Inter-molecular diffusion, Interfacial temperature profiles

Direct alcohol fuel cells (DAFCs) has been recognized as a green and substantial energy source in the near future. Due to the excellent electrocatalytic activities of palladium-based electrocatalysts for alcohol oxidation in alkaline medium, controllable synthesis of Pd-based bimetallic nanocrystals to maximize its activity while simultaneously decreasing the required amount of Pd is very important for the commercializaiton of DAFCs. Here, a novel PdAg naocrystal with unique structure is synthesized by the galvanic replacement reaction between pre-synthesized Ag nanowires and palladium precursor. X-ray diffraction and high-resolution transmission electron microscopy demonstrate that the obtained PdAg naocrystals display a tubular alloy nanostructure with hollow interiors and porous walls. Moreover, the electrochemical studies indicate that the as-prepared PdAg alloy nanotubes (PdAg-ANTs) exhibit excellent electrocatalytic activity and stability towards ethanol electrooxidation in alkaline media, showing its great potential for use as anode catalysts in alkaline DAFCs. The enhanced electrocatalytic activity of the prepared PdAg-ANTs can be attributed to the formation of alloy between Ag and Pd atoms, structural effect and the unique nanostructure.

In this paper, we report the first successful demonstration of the direct growth of high-quality two-dimensional (2D) MoS2 semiconductors on a flexible substrate using a 25-m-thick Yttria-stabilized zirconia ceramic substrate. Few-layered MoS2 crystals grown at 800 &deg, C showed a uniform crystal size of approximately 50 m, which consisted of about 10 MoS2 layers. MoS2 crystals were characterized using energy-dispersive X-ray spectroscopy. Raman spectroscopy was performed to investigate the crystal quality under bending conditions. The Raman mapping revealed a good uniformity with a stable chemical composition of the MoS2 crystals. Our approach offers a simple and effective route to realize various flexible electronics based on MoS2. Our approach can be applied for MoS2 growth and for other 2D materials. Therefore, it offers a new opportunity that allows us to demonstrate high-performance flexible electronic/optoelectronic applications in a less expensive, simpler, and faster manner without sacrificing the intrinsic performance of 2D materials.

Summary Bacterial wilt caused by Ralstonia solanacearum is a ruinous soilborne disease affecting more than 450 plant species. Efficient control methods for this disease remain unavailable to date. This study characterized a novel nucleotide‐binding site‐leucine‐rich repeat resistance gene AhRRS5 from peanut, which was up‐regulated in both resistant and susceptible peanut cultivars in response to R. solanacearum. The product of AhRRS5 was localized in the nucleus. Furthermore, treatment with phytohormones such as salicylic acid (SA), abscisic acid (ABA), methyl jasmonate (MeJA) and ethephon (ET) increased the transcript level of AhRRS5 with diverse responses between resistant and susceptible peanuts. Abiotic stresses such as drought and cold conditions also changed AhRRS5 expression. Moreover, transient overexpression induced hypersensitive response in Nicotiana benthamiana. Overexpression of AhRRS5 significantly enhanced the resistance of heterogeneous tobacco to R. solanacearum, with diverse resistance levels in different transgenic lines. Several defence‐responsive marker genes in hypersensitive response, including SA, JA and ET signals, were considerably up‐regulated in the transgenic lines as compared with the wild type inoculated with R. solanacearum. Nonexpressor of pathogenesis‐related gene 1 (NPR1) and non‐race‐specific disease resistance 1 were also up‐regulated in response to the pathogen. These results indicate that AhRRS5 participates in the defence response to R. solanacearum through the crosstalk of multiple signalling pathways and the involvement of NPR1 and R gene signals for its resistance. This study may guide the resistance enhancement of peanut and other economic crops to bacterial wilt disease.

Nanoporous Ni Cu P amorphous alloy (NPA NiCuP) and nanoporous Ni Cu crystalline alloy (NP NiCu) have been prepared by potentiostatic etching of copper from the electroless Ni Cu P and Ni Cu alloy platings, respectively. The results of X-ray Diffraction (XRD), Energy Dispersion Spectrum (EDS) and Scanning Electron Microscopy (SEM) indicate that the NPA–NiCuP alloy is amorphous structure and shows a porous network structure with the pore size of 100–300 nm. The electrocatalytic oxidation of hydrazine in alkaline media is investigated by cyclic voltammetry (CV) and double potential step chronoamperometry (DPSCA). The results suggest that the proton diffusion coefficient of redox species and the reaction rate constant of the NPA–NiCuP alloy electrode in KOH solution are higher than those of the smooth electroless Ni Cu P amorphous (SA–NiCuP) and NP–NiCu alloy electrodes. In addition, the NPA–NiCuP electrode has higher anodic oxidation peak current density and lower onset oxidation potential of hydrazine in KOH solution than the SA–NiCuP and NP–NiCu electrodes. Finally, the CV measurement suggests that the NPA–NiCuP electrode has a relatively stable redox behavior.

Calcium is a universal signal in the regulation of wide aspects in biology, but few are known about the function of calcium in the control of early embryo development. Ca(2+) deficiency in soil induces early embryo abortion in peanut, producing empty pods, which is a general problem; however, the underlying mechanism remains unclear. In this study, embryo abortion was characterized to be caused by apoptosis marked with cell wall degradation. Using a method of SSH cDNA libraries associated with library lift (SSHaLL), 62 differentially expressed genes were isolated from young peanut embryos. These genes were classified to be stress responses, catabolic process, carbohydrate and lipid metabolism, embryo morphogenesis, regulation, etc. The cell retardation with cell wall degradation was caused by up-regulated cell wall hydrolases and down-regulated cellular synthases genes. HsfA4a, which was characterized to be important to embryo development, was significantly down-regulated under Ca(2+) -deficient conditions from 15 days after pegging (DAP) to 30 DAP. Two AhCYP707A4 genes, encoding abscisic acid (ABA) 8'-hydroxylases, key enzymes for ABA catabolism, were up-regulated by 21-fold under Ca(2+) -deficient conditions upstream of HsfA4a, reducing the ABA level in early embryos. Over-expression of AhCYP707A4 in Nicotiana benthamiana showed a phenotype of low ABA content with high numbers of aborted embryos, small pods and less seeds, which confirms that AhCYP707A4 is a key player in regulation of Ca(2+) deficiency-induced embryo abortion via ABA-mediated apoptosis. The results elucidated the mechanism of low Ca(2+) -induced embryo abortion and described the method for other fields of study.

Well-dispersed PdxAgy alloy nanoparticles supported on reduced graphene oxide (RGO) sheets (PdxAgy/RGO) are successfully synthesized by in situ reduction precipitation using hydrothermal synthesis method. The as-prepared Pd1Ag1/RGO nanocomposite exhibits higher electrocatalytic activities than the commercial Pd/C catalyst for ethanol electro-oxidation in alkaline medium.

(R,E)-N-(3-(2-acetamido-3-(benzyloxy) propanamido)propyl)-2-cyano-3-(4-hydroxy phenyl)acrylamide (hr5F) was design-synthesized based on bioactivity focus strategy as a potential agent to treat diabetic complicates. With in vitro enzyme assay, it is confirmed that hr5F is an effective ALR2 inhibitor with IC50 value of 2.60 ± 0.15 nM, and selectivity index of 86.0 over ALR1, which is a little bit better than the reference Epalrestat (Epa). hr5F inhibits the increase of ALR2 enzyme activity and expression in human lens epithelial cells (HLECs) induced by high glucose. By applying western blot, it was found that hr5F alleviates the high glucose-induced superoxide overproduction insults by regulating SIRT1-PGC-1α/Nrf2 pathway, together with regulating NRF-1, mtTFA, Bax/Bcl-2 to ameliorate cell apoptosis. The in vivo effects of hr5F on short term streptozocin (STZ)-induced diabetic mice confirm the same functions disclosed in vitro. All the evidences support that hr5F may serve as a promising agent in the treatment of diabetic complications with close efficacy and broader indication than the reference Epa.

ABA is an important messenger that acts as a signaling mediator for regulating the adaptive response of plants to drought stress. Two production pathways, de novo biosynthesis and hydrolysis of glucose-conjugated ABA by β-glucosidase (BG), increase cellular ABA levels in plants. ABA catabolism via hydroxylation by 8’-hydroxylase (CYP707A), or conjugation by uridine diphosphate glucosyltransferase (UGT), decreases cellular ABA levels. The transport of ABA through ATP-binding cassette (ABC)-containing transporter proteins, members of ABC transporter G family (ABCG), across plasma membrane (PM) is another important pathway to regulate cellular ABA levels. In this study, based on our previously constructed transcriptome of peanut leaves in response to drought stress, fourteen candidate genes involved in ABA production (including AhZEP, AhNCED1 and AhNCED3, AhABA2, AhAAO1 and AhAAO2, AhABA3, AhBG11 and AhBG24), catabolism (including AhCYP707A3, AhUGT71K1 and AhUGT73B4) and transport (including AhABCG22-1 and AhABCG22-2), were identified homologously and phylogenetically, and further analyzed at the transcriptional level by real-time RT-PCR, simultaneously determining ABA levels in peanut leaves in response to drought. The high sequence identity and very similar subcellular localization of the proteins deduced from 14 identified genes involved in ABA production, catabolism and transport with the reported corresponding enzymes in databases suggest their similar roles in regulating cellular ABA levels. The expression analysis showed that the transcripts of AhZEP, AhNCED1, AhAAO2 and AhABA3 instead of AhABA2, AhNCED3 and AhAAO1 in peanut leaves increased significantly in response to drought stress; and that the AhBG11 and AhBG24 mRNA levels were rapidly and significantly up-regulated, with a 4.83- and 4.58-fold increase, respectively at 2-h of drought stress. The genes involved in ABA catabolism AhCYP707A3, AhUGT71K1 instead of AhUGT73B4 were significantly induced in response to drought stress. The expression of two closely related peanut ABCG genes, AhABCG22.1 and AhABCG22.2, was significantly up-regulated in response to drought stress. The ABA levels rapidly began to accumulate within 2 h (a 56.6-fold increase) from the start of drought stress, and peaked at 10 h of the stress. The highly and rapidly stress up-regulated expressions of genes involved in ABA production and transport, particularly AhNCED1, AhBG11 and AhBG24, and AhABCG22.1 and AhABCG22.2, might contribute to the rapid ABA accumulation in peanut leaves in response to drought. In response to drought stress, ABA accumulation levels in peanut leaves agree well with the up-regulated expressions of ABA-producing genes (AhZEP, AhNCED1, AhAAO2, AhABA3, AhBG11 and AhBG24) and PM-localized ABA importer genes (AhABCG22-1 and AhABCG22-2), in spite of the simultaneously induced ABA catabolic genes (AhCYP707A3 and AhUGT71K1), although the induction of catabolic genes was much lower than that of biosynthetic gene (AhNCED1). This difference in induction kinetics of gene expression may define the significant accumulation of drought-induced ABA levels. These results suggest that ABA homeostasis in peanut leaves in response to drought maintained through a balance between the production, catabolism and transport, rather than simply by the biosynthesis.

Poncirin is a bitter flavanone glycoside with various biological activities. Poncirin was isolated from four different tissues (flavedo, albedo, segment membrane, and juice sac) of Ougan fruit (Citrus reticulate cv. Suavissima). The highest content of poncirin was found in the albedo of Ougan fruit (1.37 mg/g DW). High speed counter-current chromatography (HSCCC) combined with D101 resin chromatography was utilized for the separation and purification of poncirin from the albedo of Ougan fruit. After this two-step purification, poncirin purity increased from 0.14% to 96.56%. The chemical structure of the purified poncirin was identified by both HPLC-PDA and LC-MS. Poncirin showed a significant in vitro inhibitory effect on the growth of the human gastric cancer cells, SGC-7901, in a dose-dependent manner. Thus, poncirin from Ougan fruit, may be beneficial for gastric cancer prevention. The purification method demonstrated here will be useful for further studies on the pharmacological mechanism of poncirin activity, as well as for guiding the consumption of Ougan fruit.

Chinese bayberry (Myrica rubra Sieb. & Zucc.) is a rich source of cyanidin-3-O-glucoside (C3G). Purification of C3G was established by using high-speed counter-current chromatography (HSCCC) at 520 nm. The optimised flow rate was 2 ml/min and rotational speed was 850 rpm, and n-butanol–methyl tertiary butyl ether–acetonitrile–trifluoroacetic acid–water (30:20:40:1:100, v/v/v/v/v) solvent showed the highest partition coefficient (K = 1.50) to purify C3G. Different HSCCC fractions showed significant different anti-tumour effect on SGC7901, AGS, and BGC823 gastric cells, which were correlated with their C3G concentrations and DPPH• scavenging activities. Cells treated with C3G resulted in reduced cell proliferation, decreased cell adherence, and abnormal morphological changes characteristics of apoptosis, all in dose-dependent manners. In addition, increased concentrations of C3G treatment resulted in increased inhibition of matrix metalloproteinase 2 (MMP-2) in SGC7901 cells, which may provide important information for the possible mechanism of C3G-induced anti-tumour activity against gastric adenocarcinoma cells.