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Plants have had numerous biological, clinical, pharmaceutical and medicinal purposes for many years; however, their use as a general platform for preparation of desired pharmaceutical and biomedical compounds is relatively current. Secondary metabolites with remarkable and diverse biological functions are produced by medicinal plants. Significant advancements in nanosciences have enabled their various applications in the development of a new generation of drug molecules. Due to the application of toxic solvents and high energy consumption of conventional physical and chemical approaches, greener and eco-friendly methods are essential and vital. Plants can provide an outstanding alternative for the production of phytomaterials and biomaterials, and this review highlights the exogenous and endogenous syntheses of nanoparticles using living plants. Additionally, the plant nano-molecular farming of proteins including collagen, gelatin, elastin, recombinant anti-cancer monoclonal antibodies and recombinant anti-cancer vaccines is discussed. [ABSTRACT FROM AUTHOR]

The AgGeSe2 solid state electrolyte has been studied in resistive switching. According to the I-V relationship, the possible mechanisms, including the SCLC (space-charge-limited current) model is applied to explain the result of experiments. The conductive filament formation is found to be related to the Schottky barrier between the electrode and electrolyte. [ABSTRACT FROM AUTHOR]

Transition metal-oxide resistive random-access memories seem to be a viable candidate as the next-generation storage technology because transition metals have multiple oxidation states and are good ionic conductors. A wide range of transition metal oxides have recently been studied; however, fundamental understanding of the switching mechanism is still lacking. Migration energies and diffusivity of oxygen vacancies in amorphous and crystalline $$\hbox {HfO}_{2}$$ and $$\hbox {CeO}_{2}$$ and at their interface are investigated by employing density functional theory. We found that oxygen dynamics is better in $$\hbox {CeO}_{2}$$ compared to $$\hbox {HfO}_{2}$$ , including smaller activation energy barriers and larger diffusion pre-factors, which can have implications in the material-selection process to determine which combination of materials offer the most efficient switching. Furthermore, we found that motion of vacancies is different at the interface of these two oxides as compared to that within each constituents, which provided insight into the role of the interface in vacancy motion and ultimately using interface engineering as a way to tune material properties. [ABSTRACT FROM AUTHOR]

SUMMARY A number of resistive switching memories exhibit activation-based dynamical behavior, which makes them suitable for neuromorphic and programmable analog filtering applications. Because the Boundary Condition Memristor (BCM) model accounts for tunable activation thresholds only at the on and off boundary states, it is not quantitatively accurate in the description of these kinds of memristors and in the investigation of their circuit applications. This paper introduces the Generalized Boundary Condition Memristor (GBCM) model, preserving the features of the BCM model while allowing, further, an ad-hoc tuning of activation-based dynamics, which enables an appropriate modulation of the conditions under which memristors may operate as storage elements or data processors. A simple circuit implementation of the novel model is presented, and time-efficient simulations confirming the improvement in modeling accuracy over the BCM model are shown. As a proof-of-concept for the suitability of the GBCM model in the exploration of the full potential of memristors in neuromorphic circuits and programmable analog filters, this paper adopts it to model fundamental synaptic rules governing the mechanisms of learning in neural systems and to gain some insight into key issues in the design of a couple of filters. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]