Alzheimer’s disease (AD) affects a significant portion of humanity’s elderly population across the globe. Recent studies have identified Amyloid-Beta 42 (Aβ42) as a key biomarker for AD. In this research, we examined the feasibility of using string-shaped electrodes to develop a potentially wearable biosensor for the early detection of AD. Two types of flexible electrochemical electrodes were fabricated using a commercial thread (25% cotton-75% polyester) and an electrospun nanofiber-based string. Decorating the strings with either gold or SiC nanoparticles, several different electrodes were tested to explore their responses to Aβ42. Our results show that the nanofiber-based electrode decorated with gold nanoparticles had the highest sensitivity of 1.71 µA/pg.cm and the best limit of detection (LoD) of 8.36 pg/mL. These findings highlight the importance of the string structure in designing highly sensitive sensors.

As the healthcare industry continues to evolve its approach to monitoring patient health, the growing need for rapid accurate biosensing in a wearable device is becoming more and more relevant. Along with size, weight, and various technology constraints, making a nanoscale biosensor can be beneficial in furthering this exploratory venture. In this work, string-shaped electrodes have been fabricated by coating PEDOT:PSS on commercially available threads. Some of the electrodes were further coated with a solution containing SnO2 nanoparticles. By immobilizing glucose oxidase (GOx) on the strings, the electrodes were electrochemically characterized when they were exposed to the electrolytes containing glucose. The cyclic voltammetry and electrochemical impedance spectroscopy results show that the presence of NPs has a significant effect on electrochemical response of the electrodes particularly after the immobilization of GOx. The chronoamperometry (CA) studies of the two electrodes verifiy the impact of NPs in the sensitivity of the electrodes reaching 83.70 µA/mMcm2. The promising results from this work encourage designing wearable sensors with the string-shaped electrodes coated with SnO2 nanoparticles for future wearable sensors.

Women of Color faculty continue to experience many challenges in their careers, especially in the science, technology, engineering, and mathematics (STEM) fields. As such, more research is needed that considers structural issues inhibiting their success. Using structuration theory and critical race feminism as a conceptual framework, we conducted semi-structured interviews with 19 faculty and administrators in STEM departments at higher education institutions to investigate their perceptions of structural impediments impacting early-career Women of Color STEM faculty careers. Our findings revealed the need to establish policies that are clear, documented, and transparent. Additionally, incremental approaches to tenure and promotion evaluations should be reconsidered, especially when this approach may position Women of Color faculty to appear as if they are underperforming, when the opposite may be true. Furthermore, as higher education institutions endeavor to diversify the professoriate, this study is significant in enabling institutions and STEM departments to be aware of systemic issues confronting them to make significant inroads in retaining and advancing Women of Color faculty in these disciplines.

The mass production and use of Li batteries have raised serious concerns about their impact on the environment. Supercapacitors are an alternative energy storage device. This paper addresses a new approach to fabricating supercapacitors using the BioX6 Bioprinter from Cellink. A series of experiments were conducted to derive a conductive bioink capable of being implemented as a viable material for energy storage devices. This bioink in conjunction with a gel electrolyte was utilized for the fabrication of supercapacitors in a planar structure. This study utilizes the VersaStat 4 Potentiostat to measure each capacitors’ response. Devices with capacitances as high as 53.52 µF were fabricated and tested. The results of this study show the feasibility of using the bioprinting method for fabricating prototype storage devices.

Nanofiber technology is leading the revolution of wearable technology and provides a unique capability to fabricate smart textiles. With the novel fabrication technique of electrospinning, nanofibers can be fabricated and then manufactured into a durable conductive string for the application of smart textiles. This paper presents an electrospun nanofiber mesh-based (NF-Felt) string electrode with a conducting polymer coating for an electrochemical enzymatic glucose sensor. The surface area of a nanofiber matrix is a key physical property for enhanced glucose oxidase (GOx) enzyme binding for the development of an electrochemical biosensor. A morphological characterization of the NF-Felt string electrode was performed using scanning electron microscopy (SEM) and compared with a commercially available cotton–polyester (Cot-Pol) string coated with the same conducting polymer. The results from stress–strain testing demonstrated high stretchability of the NF-Felt string. Also, the electrochemical characterization results showed that the NF-Felt string electrode was able to detect a glucose concentration in the range between 0.0 mM and 30.0 mM with a sensitivity of 37.4 μA/mM·g and a detection limit of 3.31 mM. Overall, with better electrochemical performance and incredible flexibility, the NF-Felt-based string electrode is potentially more suitable for designing wearable biosensors for the detection of glucose in sweat.

In this study, morphology and in vitro response of electroconductive composite nanofibers were explored for biomedical use. The composite nanofibers were prepared by blending the piezoelectric polymer poly(vinylidene fluoride-trifluorethylene) (PVDF-TrFE) and electroconductive materials with different physical and chemical properties such as copper oxide (CuO), poly(3-hexylthiophene) (P3HT), copper phthalocyanine (CuPc), and methylene blue (MB) resulting in unique combinations of electrical conductivity, biocompatibility, and other desirable properties. Morphological investigation via SEM analysis has remarked some differences in fiber size as a function of the electroconductive phase used, with a reduction of fiber diameters for the composite fibers of 12.43% for CuO, 32.87% for CuPc, 36.46% for P3HT, and 63% for MB. This effect is related to the peculiar electroconductive behavior of fibers: measurements of electrical properties showed the highest ability to transport charges of methylene blue, in accordance with the lowest fibers diameters, while P3HT poorly conducts in air but improves charge transfer during the fiber formation. In vitro assays showed a tunable response of fibers in terms of viability, underlining a preferential interaction of fibroblast cells to P3HT-loaded fibers that can be considered the most suitable for use in biomedical applications. These results provide valuable information for future studies to be addressed at optimizing the properties of composite nanofibers for potential applications in bioengineering and bioelectronics.

The COVID-19 pandemic highlighted two critical barriers hindering rapid response to novel pathogens. These include inefficient use of existing biological knowledge about treatments, compounds, gene interactions, proteins, etc. to fight new diseases, and the lack of assimilation and analysis of the fast-growing knowledge about new diseases to quickly develop new treatments, vaccines, and compounds. Overcoming these critical challenges has the potential to revolutionize global preparedness for future pandemics. Accordingly, this article introduces a novel knowledge graph application that functions as both a repository of life science knowledge and an analytics platform capable of extracting time-sensitive insights to uncover evolving disease dynamics and, importantly, researchers' evolving understanding. Specifically, we demonstrate how to extract time-bounded key concepts, also leveraging existing ontologies, from evolving scholarly articles to create a single temporal connected source of truth specifically related to COVID-19. By doing so, current knowledge can be promptly accessed by both humans and machines, from which further understanding of disease outbreaks can be derived. We present key findings from the temporal analysis, applied to a subset of the resulting knowledge graph known as the temporal keywords knowledge graph, and delve into the detailed capabilities provided by this innovative approach.

In the contemporary world, wearable electronics and smart textiles/fabrics are galvanizing a transformation of the health care, aerospace, military, and commercial industries. However, a major challenge that exists is the manufacture of electronic circuits directly on fabrics. In this work, we addressed the issue by developing a sequential manufacturing process. First, the target fabric was coated with a customized ink containing lignin. Next, a desired circuit layout was patterned by laser burning lignin, converting it to carbon and establishing a conductive template on the fabric. At last, using an in-house-designed printer, a devised localized hydrogen evolution-assisted (HEA) copper electroplating method was applied to metalize the surface of the laser-burned lignin pattern to achieve a very low resistive circuit layout (0.103 Ω for a 1 cm long interconnect). The nanostructure and material composition of the different layers were investigated via scanning electron microscopy, energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and Fourier-transform infrared spectroscopy (FTIR). Monitoring the conductivity change before and after bending, rolling, stretching, washing, and adhesion tests presented remarkable mechanical stability due to the entanglement of the copper nanostructure to the fibers of the fabric. Furthermore, the HEA method was used to solder a light-emitting diode to a patterned circuit on the fabric by growing copper at the terminals, creating interconnects. The presented sequential printing method has the potential for fabricating reliable wearable electronics for various applications, particularly in medical monitoring.

Fiber electronics, such as those produced by the electrospinning technique, have an extensive range of applications including electrode surfaces for batteries and sensors, energy storage, electromagnetic interference shielding, antistatic coatings, catalysts, drug delivery, tissue engineering, and smart textiles. New composite materials and blends from conductive–semiconductive polymers (C-SPs) offer high surface area-to-volume ratios with electrical tunability, making them suitable for use in fields including electronics, biofiltration, tissue engineering, biosensors, and “green polymers”. These materials and structures show great potential for embedded-electronics tissue engineering, active drug delivery, and smart biosensing due to their electronic transport behavior and mechanical flexibility with effective biocompatibility. Doping, processing methods, and morphologies can significantly impact the properties and performance of C-SPs and their composites. This review provides an overview of the current literature on the processing of C-SPs as nanomaterials and nanofibrous structures, mainly emphasizing the electroactive properties that make these structures suitable for various applications.

According to data from the U.S. Center for Disease Control and Prevention, as of June 2020, a significant number of African Americans had been infected with the coronavirus disease, experiencing disproportionately higher death rates compared to other demographic groups. These disparities highlight the urgent need to examine the experiences, behaviors, and opinions of the African American population in relation to the COVID-19 pandemic. By understanding their unique challenges in navigating matters of health and well-being, we can work towards promoting health equity, eliminating disparities, and addressing persistent barriers to care. Since Twitter data has shown significant promise as a representation of human behavior and for opinion mining, this study leverages Twitter data published in 2020 to characterize the pandemic-related experiences of the United States' African American population using aspect-based sentiment analysis. Sentiment analysis is a common task in natural language processing that identifies the emotional tone (i.e., positive, negative, or neutral) of a text sample. Aspect-based sentiment analysis increases the granularity of sentiment analysis by also extracting the aspect for which sentiment is expressed. We developed a machine learning pipeline consisting of image and language-based classification models to filter out tweets not related to COVID-19 and those unlikely published by African American Twitter subscribers, leading to an analysis of nearly 4 million tweets. Overall, our results show that the majority of tweets had a negative tone, and that the days with larger numbers of published tweets often coincided with major U.S. events related to the pandemic as suggested by major news headlines (e.g., vaccine rollout). We also show how word usage evolved throughout the year (e.g., outbreak to pandemic and coronavirus to covid). This work also points to important issues like food insecurity and vaccine hesitation, along with exposing semantic relationships between words, such as covid and exhausted. As such, this work furthers understanding of how the nationwide progression of the pandemic may have impacted the narratives of African American Twitter users.

This chapter will focus on the fabrication and morphological and electrochemical characterization of silicon carbide (SiC) nanostructures (particles, fibers, laminates, thin films) used to develop electrochemical glucose biosensors. Glucose oxidase enzymes coimbedded in a conductive polymer with silicon carbide nanostructures exhibit high sensitivity, quick response time, and enhanced limit of detection and durability. SiC nanoparticles (SiCNPs) spin-coated-thin-films and SiCNPs electrospun-nanofibrous-membranes have been implemented as glucose-sensing electrodes, and a comparative analysis of SiCNPs with both ENFMs and SCTFs has been conducted. Prior research has shown that conducting polymers could be utilized as a mediator for the detection of glucose. This is presumably due to direct electron transfer between glucose oxidase and the conducting polymer, which is an oxygen-independent detection mechanism. This chapter presents the feasibility of using electrodes containing embedded SiC nanostructures as an emerging approach to fabricating highly sensitive glucose biosensors.

In this work, the electrospinning technique is used to fabricate a polymer-polymer coaxial structure nanofiber from the p-type regioregular polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) and the n-type conjugated ladder polymer poly(benzimidazobenzophenanthroline) (BBL) of orthogonal solvents. Generally, the fabrication of polymeric coaxial nanostructures tends to be troublesome. Using the electrospinning technique, P3HT was successfully used as the core, and the BBL as the shell, thus conceptually forming a p-n junction that is cylindrical in form with diameters in a range from 280 nm to 2.8 µm. The UV–VIS of P3HT/PS blend solution showed no evidence of separation or precipitation, while the combined solutions of P3HT/PS and BBL were heterogeneous. TEM images show a well-formed coaxial structure that is normally not expected due to rapid reaction and solidification when mixed in vials in response to orthogonal solubility. For this reason, extruding it by using electrostatic forces promoted a quick elongation of the polymers while forming a concise interface. Single nanofiber electrical characterization demonstrated the conductivity of the coaxial surface of ~1.4 × 10−4 S/m. Furthermore, electrospinning has proven to be a viable method for the fabrication of pure semiconducting coaxial nanofibers that can lead to the desired fabrication of fiber-based electronic devices.

This chapter presents an overview and a conceptual approach of culturally relevant mentoring at an institution of higher learning from the lens of the authors. There are various types of mentoring approaches that demonstrate the opportunity for institutional leaders to align their strategic initiatives with the academic and career success of dissertators, postdoctoral researchers, and early career faculty. This work places a focus on culturally relevant mentoring as a tactical approach for creating strategic dialogue of critical consciousness to produce core values, institutional commitments, and strategic plans that reflect the culture of all stakeholders. Culturally relevant mentoring promotes active acknowledgement of cultural contributions, inclusive social context, and equitable and just strategies for institutional climate change that will differentiate an institution from its peers in higher education.

Electrospinning is an inexpensive and versatile technique for fabricating micro- and nano- scaled fibers. There have been limited attempts to employ it for the fabrication of thermochromic (TC) fibers, and the fabrication of a three-component (dye, developer, and solvent) TC material has required the use of a more complicated coaxial electrospinning technique. Herein, a simple and novel method for creating thermochromic fibers by electrospinning single strands of poly (methyl methacrylate) (PMMA) with embedded thermochromic powder of a polymer encapsulated three-component system was employed. Unlike past leuco dye-based thermochromic fibers, an unmodified syringe tip can be used for the spinning process and only one flow rate needs to be determined. A solution of solvent (either N-dimethylformamide or chloroform), PMMA, and a commercially available black thermochromic powder was prepared and spun using a custom-made electrospinning apparatus. The spun fibers exhibited a clear color transition from grey to white and had average diameters of 2.53 µm and 1.96 µm for chloroform and N-dimethylformamide based fibers, respectively. The fibers were characterized by scanning electron and optical microscopy to determine their morphology, Fourier transform infrared spectroscopy to determine their chemical composition, and differential scanning calorimetry and thermogravimetric analysis to characterize their thermal properties.

The design and implementation of a voltage mode integrated on-chip DC-DC buck converter for continuous blood glucose monitoring systems with power efficiency of 89% is presented in this paper. The proposed converter circuit not only can reach high efficiency but also has high switching frequency of 50 MHz. A great improvement in settling time of 250 ns was observed with on-chip passive components. A preamplifier based comparator with high speed, low offset voltage, and less delay was used for pulse-width-modulator (PWM) controller. Power losses are reduced by introducing dead time circuit to eliminate shoot-through condition.

This work presents, silicon carbide nanoparticles (SiCNPs) embedded in a conductive polymer (CP) to be electrospun to fabricate a nanofibrous membrane and a thin-film. Electrochemical enzymatic glucose sensing mechanism of an electrospun nanofibrous membrane (ENFM) of SiCNPs in a CP compared to a spin-coated-thin-film (SCTF) of SiCNPs in a CP. Fiber alignment in the form of a matrix is a key factor that determines the physical properties of nanofiber membrane compared to thin-film. It is found that glucose sensing electrodes formed by a SiCNPs-ENFM has enhanced binding of the glucose oxidase (GOx) enzyme within the fibrous membrane as compared to a SiCNPs-SCTF. The SiCNPs-ENFM and SiCNPs-SCTF glucose sensing electrodes were characterized for morphology by using scanning electron microscopy (SEM) and for electrochemical activity by using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA) methods. SiCNPs-ENFM based glucose electrodes shown a detection range from a 0.5 mM to 20 mM concentration with a better sensitivity of [Formula: see text]/gmMcm2, and low limit of detection (LOD) 552.89 nM compared to SiCNPs-SCTF with sensitivity of [Formula: see text]/gmMcm2 and LOD of [Formula: see text]. The change in current level with SiCNPs-ENFM was ~14% contrast to ~75% with the SiCNPs-SCTF based glucose sensor over 50 days. The electrochemical analysis results demonstrated that the SiCNPs-ENFM electrode provides enhanced sensitivity, better limit of detection (LOD), and durability compared to SiCNPs-SCTF based glucose sensing electrode.

Recently, we have demonstrated that hydrogen evolution-assisted (HEA) electroplating can be used for rapid lateral growth of copper across a gap between two copper traces on a printed circuit board (PCB). In this work, the HEA approach has been applied for growing copper traces on three different fabrics of 1000 Denier-Coated Cordura Nylon, Laminated Polyester Ripstop, and 100% Virgin Vinyl. To provide the conductive path for the electroplating, first, the desired pattern was applied as a template on the fabric using a conductive ink including multiwalled carbon nanotubes (MWNTs). The template was then metalized by coating it with copper. The fastest copper lateral growth rate was achieved in 1000 Denier-Coated Cordura Nylon sample (370.96 μm/s), while 100% Virgin Vinyl sample showed the slowest growth rate of 99.57 μm/s. Further study of the morphologies using the scanning electron microscopy technique showed that the material and the texture of the fabric directly affect the morphology of the electroplated copper. The results are very promising for developing a new method of fabricating wearable electronics by directly printing copper on different fabrics.

Recent progress in hydrogen evolution assisted (HEA) electroplating has shown promises for fast lateral growth of copper on various rigid and flexible substrates. In this method, concurrent to the copper reduction, hydrogen bubbles are generated at the cathode resulting in a porous copper layer with a growth rate a few orders of magnitude faster than the standard electroplating method. However, the application of constant voltage does not allow bubbles to leave the surface resulting in non-uniform copper growth and unpredictable nanostructures. To allow the hydrogen bubbles to leave the surface, we have applied a cyclic electroplating method in a voltage range that the electroplating alternates between the HEA and non-HEA modes. The effect of the voltage range and the voltage scan rate on the lateral growth of copper and the quality of the copper layer were investigated on a patterned copper track on a standard printed circuit board (PCB). The fastest growth rate of 55 mu m/s was obtained for a voltage range between -1.5 V and -0.8 V with a scan rate of 100 mV/s. The scanning electron microscopy (SEM) images of different samples revealed that the scan rate affects the nanostructure of the grown copper layer. The feasibility of applying the HEA cyclic electroplating method for developing wearable electronics was demonstrated by growing copper on a piece of fabric to make contact with the pins of a light emitting diode.