Recent biological research has demonstrated that redox is an independent biological-signaling modality. [1-8] This redox signaling modality is best understood in host-pathogen immune interactions where an oxidative burst generates a set of reactive species (e.g., reactive oxygen species) that can sometimes be transduced into second messengers (i.e., reactive electrophiles) [4] and ultimately alters biological function through post-translational protein modification (e.g., conversion of protein cysteine residues into disulfide crosslinks). [6] The functions and the coding of information in this redox signaling modality [1] are distinctly different from the information coded in genes or in the action potentials of the ionic electrical modality. Since this redox modality involves the "flow" of electrons through oxidation-reduction reactions, it is accessible to appropriate electrochemical measurement, and this provides new opportunities for biodevice communication. [9-13] Redox has similarities to the ionic electrical modality, however electrons are the charged species moving in the redox modality. Interestingly, while water is a conductor of ionic currents, it can be considered an "insulator" for the flow of electrons since free electrons do not normally exist in aqueous

While conventional material fabrication methods focus on form and strength to achieve function, the fabrication of material systems for emerging life science applications will need to satisfy a more subtle set of requirements. A common goal for biofabrication is to recapitulate complex biological contexts (e.g. tissue) for applications that range from animal-on-a-chip to regenerative medicine. In these cases, the material systems will need to: (i) present appropriate surface functionalities over a hierarchy of length scales (e.g. molecular features that enable cell adhesion and topographical features that guide differentiation); (ii) provide a suite of mechanobiological cues that promote the emergence of native-like tissue form and function; and (iii) organize structure to control cellular ingress and molecular transport, to enable the development of an interconnected cellular community that is engaged in cell signaling. And these requirements are not likely to be static but will vary over time and space, which will require capabilities of the material systems to dynamically respond, adapt, heal and reconfigure. Here, we review recent advances in the use of electrically based fabrication methods to build material systems from biological macromolecules (e.g. chitosan, alginate, collagen and silk). Electrical signals are especially convenient for fabrication because they can be controllably imposed to promote the electrophoresis, alignment, self-assembly and functionalization of macromolecules to generate

transformers [2] and load bearing applications. [3] In the last few decades, the study of nanomaterials has become a central focus in nanoscience and nanotechnology. [4] In fact, many studies have shown that with reduction in size, nanomaterials display novel electrical, mechanical, chemical and optical properties, which are largely believed to be the result of surface and quantum confinement effects. [4,5] Remarkably, this trend has found traction in the metallic glass field where metallic glasses nanostructures (MGNs) demonstrate an important role in many applications such as light harvesting, [6] photovoltaic, [7] biomedical, [8] magneto-optical, [9] organic synthesis, [10] lithium-ion batteries [11] and electrocatalysis. [12] Recently, MGNs are receiving increased attention due to their distinguished performance, such as high activity and long term stability in electrocatalytic reactions. [12,13] Although several review papers have already covered the topic of nanopatterning of bulk metallic glasses (BMGs), [14][15][16] the correlation between recent synthetic methods and electrocatalytic applications for MGNs has not been thoroughly addressed. Moreover, there is currently no review that unites MGNs synthesized from different approaches (top-down and bottom-up) with conventional electrochemical reactions. Therefore, in this review our mission is to: 1) present a focused perspective on the latest fabrication techniques of MGNs toward the pursuit of novel electrocatalysts and electrodes; 2) highlight recent advances in computational screening and predictions that could be applied toward new metallic glass electrocatalyst discovery; and 3) report distinct advancements in electrocatalytic applications related to MGNs by creating a comprehensive discussion for commonly employed kinetic parameters and their connection with the unique material structure. Finally, as the first progress report on the metallic glass based electrocatalysts, we will also highlight some of the challenges that need to be addressed toward future progress in this field.BMGs are those metallic glasses (MGs) that can be made in 'bulk' scale with good glass forming abilities, [17] representing a versatile platform for many applications. To date, a wide range of BMG-forming alloys have been developed, including Zr-, [18] Fe-, [19] Cu-, [20] Ni-, [21] Ti-, [22] Mg-, [23] Pd-, [24] Au-, [25] and Pt-based compositions. [26] Moreover, the increased disorder brought by the higher degree of multinary systems is believed to contribute to improving the glass formation. [27] The evolution to multicomponent alloys of the most recent MG studies has also made them natural candidates for catalysis. The amorphous multinary Recent advances in metallic glass nanostructures (MGNs) are reported, covering a wide array of synthesis strategies, computational discovery, and design solutions that provide insight into distinct electrocatalytic applications. A brief introduction to the development and unique features of MGNs with an overview of top-down and bottom-up sy...

A common bioelectronics goal is to enable communication between biology and electronics, and success is critically dependent on the communication modality. When a biorelevant modality aligns with instrumentation capabilities, remarkable successes have been observed (e.g., electrodes provide a powerful tool to observe and actuate biology through its ion-based electrical modality). Emerging biological research demonstrates that redox is another biologically relevant modality, and recent research has shown that advanced electrochemical methods enable biodevice communication through this redox modality. Here, we briefly summarize the biological relevance of this redox modality and the use of redox mediators to enable access to this modality through electrochemical measurements. Next, we describe the fabrication of a catechol−chitosan redox capacitor that is redox-active but nonconducting and thus offers a unique set of molecular electronic properties that enhance access to redox-based information. Finally, we cite several recent studies that demonstrate the broad potential for this capacitor to access redox-based biological information. In summary, we envision the redox capacitor will become a vital component in the integrated circuitry of redox-linked bioelectronics.

(1) Background: l-leucine (Leu) plays a positive role in regulating protein turnover in skeletal muscle in mammal. However, the molecular mechanism for the effects of Leu on muscle growth and protein deposition is not clearly demonstrated in fish. This study investigated the effects of dietary Leu on growth performance and muscle growth, protein synthesis, and degradation-related signaling pathways of hybrid catfish (Pelteobagrus vachelli♀ × Leiocassis longirostris♂). (2) Methods: A total of 630 hybrid catfish (23.19 ± 0.20 g) were fed 6 different experimental diets containing graded levels of Leu at 10.0 (control), 15.0, 20.0, 25.0, 30.0, 35.0, and 40.0 g Leu kg-1 for 8 weeks. (3) Results: Results showed that dietary Leu increased percent weight gain (PWG), specific growth rate (SGR), FI (feed intake), feed efficiency (FE), protein efficiency ratio (PER), muscle fibers diameter, and muscle fibers density; up-regulated insulin-like growth factor I (IGF-I), insulin-like growth factor I receptor (IGF-IR), proliferating cell nuclear antigen (PCNA), myogenic regulation factors (MyoD, Myf5, MyoG, and Mrf4), and MyHC mRNA levels; increased muscle protein synthesis via regulating the AKT/TOR signaling pathway; and attenuated protein degradation via regulating the AKT/FOXO3a signaling pathway. (4) Conclusions: These results suggest that Leu has potential role to improve muscle growth and protein deposition in fish, which might be due to the regulation of IGF mRNA expression, muscle growth related gene, and protein synthesis and degradation-related signaling pathways. Based on the broken-line model, the Leu requirement of hybrid catfish (23.19-54.55 g) for PWG was estimated to be 28.10 g kg-1 of the diet (73.04 g kg-1 of dietary protein). These results will improve our understanding of the mechanisms responsible for muscle growth and protein deposition effects of Leu in fish.