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For some professionally, vocationally, or technically oriented careers, curricula delivered in higher education establishments may focus on teaching material related to a single discipline. By contrast, multidisciplinary, interdisciplinary, and transdisciplinary teaching(MITT) results in improved affective and cognitive learning and critical thinking, offering learners/students the opportunity to obtain a broad general knowledge base. Chemistry is a discipline that sits at the interface of science, technology, engineering, mathematics, and medicine(STEMM) subjects (and those aligned with or informed by STEMM subjects). This article discusses the significant potential of inclusion of chemistry in MITT activities in higher education and the real-world importance in personal, organizational, national, and global contexts. It outlines the development and implementation challenges attributed to legacy higher education infrastructures (that call for creative visionary leadership with strong and supportive management and administrative functions), and curriculum design that ensures inclusivity and collaboration and is pitched and balanced appropriately. It concludes with future possibilities, notably highlighting that chemistry, as a discipline, underpins industries that have multibillion dollar turnovers and employ millions of people across the world.

We present novel voltage stimulation buffers with controlled output current, along with recording circuits featuring adjustable high-pass cut-off filtering to perform efficient stimulation while actively suppressing stimulation artifacts in high-density microelectrode arrays. Owing to the dense packing and close proximity of the electrodes in such systems, a stimulation through one electrode can cause large electrical artifacts on neighboring electrodes that easily saturate the corresponding recording amplifiers. To suppress such artifacts, the high-pass corner frequencies of all available 2048 recording channels can be raised from several Hz to several kHz by applying a “soft-reset” or pole-shifting technique. With the implemented artifact suppression technique, the saturation time of the recording circuits, connected to electrodes in immediate vicinity to the stimulation site, could be reduced to less than 150 μs. For the stimulation buffer, we developed a circuit, which can operate in two modes: either control of only the stimulation voltage or control of current and voltage during stimulation. The voltage-only controlled mode employs a local common-mode feedback operational transconductance amplifier with a near rail-to-rail input/output range, suitable for driving high-capacitive loads. The current/voltage controlled mode is based on a positive current conveyor generating adjustable output currents, whereas its upper and lower output voltages are limited by two feedback loops. The current/voltage controlled circuit can generate stimulation pulses up to 30 μA with less than ±0.1% linearity error in the low-current mode and up to 300 μA with less than ±0.2% linearity error in the high-current mode. [ABSTRACT FROM AUTHOR]

Biological cells are characterized by highly complex phenomena and processes that are, to a great extent, interdependent. To gain detailed insights, devices designed to study cellular phenomena need to enable tracking and manipulation of multiple cell parameters in parallel; they have to provide high signal quality and high-spatiotemporal resolution. To this end, we have developed a CMOS-based microelectrode array system for in vitro applications that integrates six measurement and stimulation functions, the largest number to date. Moreover, the system features the largest active electrode array area to date ( $4.48 \times 2.43$ mm2) to accommodate 59 760 electrodes, while its power consumption, noise characteristics, and spatial resolution (13.5- $\mu$ m electrode pitch) are comparable to the best state-of-the-art devices. The system includes: 2048 action potential (AP, bandwidth: 300 Hz–10 kHz) recording units, 32 local-field-potential (LFP, bandwidth: 1 Hz–300 Hz) recording units, 32 current recording units, 32 impedance measurement units, and 28 neurotransmitter detection units, in addition to the 16 dual-mode voltage-only or current/voltage-controlled stimulation units. The electrode array architecture is based on a switch matrix, which allows for connecting any measurement/stimulation unit to any electrode in the array and for performing different measurement/stimulation functions in parallel. [ABSTRACT FROM PUBLISHER]

Tissue scaffolds allowing the behaviour of the cells that reside on them to be controlled are of particular interest for tissue engineering. Herein we describe biomineralized conducting polymer-based bone tissue scaffolds that facilitate the electrical stimulation of human mesenchymal stem cells, resulting in enhancement of their differentiation towards osteogenic outcomes. [ABSTRACT FROM AUTHOR]

Tissue scaffolds allowing the behavior of the cells that reside within them to be controlled are of particular interest for tissue engineering. Herein, the preparation of conductive fiber-based bone tissue scaffolds (nonwoven mats of electrospun polycaprolactone with an interpenetrating network of polypyrrole and polystyrenesulfonate) is described that enable the electrical stimulation of human mesenchymal stem cells to enhance their differentiation toward osteogenic outcomes. [ABSTRACT FROM AUTHOR]

We report the preparation and characterization of films of electroactive supramolecular polymers based on non-electroactive oligoalanines and electroactive oligoanilines. Fibroblasts adhered to and proliferated on the films, and the delivery of the clinically relevant anti-inflammatory drug dexamethasone phosphate could be enhanced upon the application of an electrical stimulus. [ABSTRACT FROM AUTHOR]

We report biodegradable electroactive polymer (EAP)-based materials and their application as drug delivery devices. Copolymers composed of oligoaniline-based electroactive blocks linked to either polyethylene glycol or polycaprolactone blocks via ester bonds were synthesized in three steps from commercially available starting materials and isolated without the need for column chromatography. The physicochemical and electrochemical properties of the polymers were characterized with a variety of techniques. The ability of the polymers to deliver the anti-inflammatory drug dexamethasone phosphate on the application of electrochemical stimuli was studied spectroscopically. Films of the polymers were shown to be degradable and cell adhesive in vitro. Such EAP-based materials have prospects for integration in implantable fully biodegradable/bioerodible EAP-based drug delivery devices that are capable of controlling the chronopharmacology of drugs for future clinical application. [ABSTRACT FROM AUTHOR]

Back Cover: Tissue scaffolds allowing the behavior of the cells that reside within them to be controlled are of particular interest for tissue engineering. Herein, the preparation of conductive nanofiber‐based bone tissue scaffolds are described, made from nonwoven mats of electrospun polycaprolactone with an interpenetrating network of polypyrrole and polystyrenesulfonate. These scaffolds enable the electrical stimulation of human mesenchymal stem cells to enhance their differentiation toward osteogenic outcomes. Further details can be found in the article by J. G. Hardy,* M. K. Villancio‐Wolter, R. C. Sukhavasi, D. J. Mouser, D. Aguilar Jr., S. A. Geissler, D. L. Kaplan,* and C. E. Schmidt* on page 1884. [ABSTRACT FROM AUTHOR]

Objective: Demyelination that results from disease or traumatic injury, such as spinal cord injury (SCI), can have a devastating effect on neural function and recovery. Many researchers are examining treatments to minimize demyelination by improving oligodendrocyte availability in vivo. Transplantation of stem and oligodendrocyte progenitor cells is a promising option, however, trials are plagued by undirected differentiation. Here we introduce a biomaterial that has been optimized to direct the differentiation of neural progenitor cells (NPCs) toward oligodendrocytes as a cell delivery vehicle after SCI., Approach: A collagen-based hydrogel was modified to mimic the mechanical properties of the neonatal spinal cord, and components present in the developing extracellular matrix were included to provide appropriate chemical cues to the NPCs to direct their differentiation toward oligodendrocytes. The hydrogel with cells was then transplanted into a unilateral cervical contusion model of SCI to examine the functional recovery with this treatment. Six behavioral tests and histological assessment were performed to examine the in vivo response to this treatment., Main Results: Our results demonstrate that we can achieve a significant increase in oligodendrocyte differentiation of NPCs compared to standard culture conditions using a three-component biomaterial composed of collagen, hyaluronic acid, and laminin that has mechanical properties matched to those of neonatal neural tissue. Additionally, SCI rats with hydrogel transplants, with and without NPCs, showed functional recovery. Animals transplanted with hydrogels with NPCs showed significantly increased functional recovery over six weeks compared to the media control group., Significance: The three-component hydrogel presented here has the potential to provide cues to direct differentiation in vivo to encourage regeneration of the central nervous system.

Tissue scaffolds allowing the behaviour of the cells that reside on them to be controlled are of particular interest for tissue engineering. Herein we describe biomineralized conducting polymer-based bone tissue scaffolds that facilitate the electrical stimulation of human mesenchymal stem cells, resulting in enhancement of their differentiation towards osteogenic outcomes.

Aim: To demonstrate the design, fabrication and testing of conformable conducting biomaterials that encourage cell alignment., Materials & Methods: Thin conducting composite biomaterials based on multilayer films of poly(3.4-ethylenedioxythiophene) derivatives, chitosan and gelatin were prepared in a layer-by-layer fashion. Fibroblasts were observed with fluorescence microscopy and their alignment (relative to the dipping direction and direction of electrical current passed through the films) was determined using ImageJ., Results: Fibroblasts adhered to and proliferated on the films. Fibroblasts aligned with the dipping direction used during film preparation and this was enhanced by a DC current., Conclusion: We report the preparation of conducting polymer-based films that enhance the alignment of fibroblasts on their surface which is an important feature of a variety of tissues., Competing Interests: Financial & competing interests disclosure The authors thank the University of Texas at Austin for financial support of Hunil Cha, Tushar Garg, Hetian Li, David J Mouser, Rushi C Sukhavasi and Khang Tran in the form of Undergraduate Research Fellowships. The authors also thank the University of Florida for financial support in the form of startup resources. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.

Cervical spinal cord injury (cSCI) can cause devastating neurological deficits, including impairment or loss of upper limb and hand function. A majority of the spinal cord injuries in humans occur at the cervical levels. Therefore, developing cervical injury models and developing relevant and sensitive behavioral tests is of great importance. Here we describe the use of a newly developed forelimb step-alternation test after cervical spinal cord injury in rats. In addition, we describe two behavioral tests that have not been used after spinal cord injury: a postural instability test (PIT), and a pasta-handling test. All three behavioral tests are highly sensitive to injury and are easy to use. Therefore, we feel that these behavioral tests can be instrumental in investigating therapeutic strategies after cSCI.

Rodent spinal cord injury (SCI) models have been developed to examine functional and physiological deficits after spinal cord injury with the hope that these models will elucidate information about human SCI. Models are needed to examine possible treatments and to understand histopathology after SCI; however, they should be considered carefully and chosen based on the goals of the study being performed. Contusion, compression, transection, and other models exist and have the potential to reveal important information about SCI that may be related to human SCI and the outcomes of treatment and timing of intervention.

Cervical spinal cord injury (cSCI) can cause devastating neurological deficits, including impairment or loss of upper limb and hand function. Recently there has been increasing interest in cervical spinal cord injury models because the majority of spinal cord injuries are at cervical levels. Here we examined spontaneous functional recovery of adult rats with either laminectomy or lateral hemisection of the cervical spinal cord at C3-C4. Behavioral tests were carried out, including the forelimb locomotor scale (FLS), a postural instability test (PIT), a pasta-handling test that has been used to assess forepaw digit function and latency to eat, forelimb use during vertical-lateral wall exploration in a cylindrical enclosure, and vibrissae-elicited forelimb placing tests. In addition, a forelimb step-alternation test was developed to assess functional recovery at 12 weeks post-injury. All tests detected cSCI-induced deficits relative to laminectomy. Interestingly, the severity of deficits in the forelimb step-alternation test was associated with more extensive spinal damage, greater impairment, and less recovery in the FLS and other tests. For the pasta-handling test we found that rats with a milder cervical injury (alternators) were more likely to use both forepaws together compared to rats with a more severe injury (non-alternators). In addition, using the PIT, we detected enhanced function of the good limb, suggesting that neural plasticity on the unaffected side of the spinal cord may have occurred to compensate for deficits in the impaired forelimb. These outcome measures should be useful for investigating neural events associated with cSCI, and for developing novel treatment strategies.