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Electrospinning is increasingly used as a staple technology for the fabrication of nano- and micro-fibers of different materials. Most processes utilize direct current (DC) electrospinning, and a multitude of DC-electrospinning tools ranging from research to commercial production systems is currently available. Yet, there are numerous studies performed on electrospinning techniques utilizing non-DC, periodic electric fields, or alternating current (AC) electrospinning. Those studies demonstrate the strong potential of AC-electrospinning for the sustainable production of various nanofibrous materials and structures. Although tremendous progress is achieved in the development of AC-electrospinning over the last 10 years, this technique remains uncommon. This paper reviews the AC-electrospinning concepts, instrumentation, and technology. The main focus of this review is the most studied, "electric wind" driven AC-electrospinning technique tentatively named alternating field electrospinning (AFES). The latter term emphasizes the role of the AC electric field's confinement to the fiber-generating electrode and the absence of a counter electrode in such an electrospinning system. The synopses of AFES process parameters, fiber-generating spinneret designs, benefits and obstacles, advancements in AC electrospun nano/micro-fibrous materials/structures and their applications are given, and future directions are discussed., (© 2025 The Author(s). Macromolecular Rapid Communications published by Wiley‐VCH GmbH.)

Electropolymerized polypyrrole (PPy) is considered as one of the promising polymers for use in ionic-electroactive or conducting polymer (CP) actuators. Its electromechanical properties surpass those of other prominent CPs such as poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT/PSS) or polyaniline. However, freestanding and linear contracting actuator fibers made solely of electropolymerized PPy are not available yet. This work therefore targets the development of all-CP-based actuator fibers: electromechanically active PPy is electropolymerized on the surface of wet-spun, also electromechanically active PEDOT/PSS fibers. The thickness of the PPy fiber sheath is varied by using different electropolymerization durations. Mechanical and actuation properties of the different PEDOT/PPy core-sheath actuator fibers are investigated via tensile tests and isotonic actuation strain and isometric actuation force measurements, respectively. The fiber actuators show high tensile stability in both dry and aqueous conditions, rendering them highly suitable for actuation in aqueous electrolyte media. Regarding linear, untwisted, and uncoiled CP fiber actuators, the presented actuation measurements demonstrate to the best of our knowledge the highest reported linear contractile actuation strains of up to 2.2% in electrolytes and remarkable tensile actuation stresses of 1.64 MPa, as well as a high long-term cyclic actuation stability using varying actuation durations. This renders the fibers as a highly promising material, particularly with regard to their further structural textile processing for use in actuating wearables or soft robots.

Achieving both formability and functionality in thermoelectric materials remains a significant challenge due to their inherent brittleness. Previous approaches, such as polymer infiltration, often compromise thermoelectric efficiency, underscoring the need for flexible, all-inorganic alternatives. This study demonstrates that the extreme brittleness of thermoelectric bismuth telluride (Bi 2 Te 3 ) bulk compounds can be overcome by harnessing the nanoscale flexibility of Bi 2 Te 3 nanoribbons and twisting them into a yarn structure. The resulting Bi 2 Te 3 yarn, with a Seebeck coefficient of -126.6 µV K -1 , exhibits remarkable deformability, enduring extreme bending curvatures (down to 0.5 mm -1 ) and tensile strains of ≈5% through over 1000 cycles without significant resistance change. This breakthrough allows the yarn to be seamlessly integrated into various applications-wound around metallic pipes, embedded within life jackets, or woven into garments-demonstrating unprecedented adaptability and durability. Moreover, a simple 4-pair thermoelectric generator comprising Bi 2 Te 3 yarns and metallic wires generates a maximum output voltage of 67.4 mV, substantiating the effectiveness of thermoelectric yarns in waste heat harvesting. These advances not only challenge the traditional limitations posed by the brittleness of thermoelectric materials but also open new avenues for their application in wearable and structural electronics., (© 2024 Wiley‐VCH GmbH.)

The extant literature has scant detail about everyday spiritual practices that aid Indigenous young people. This paper systematically explores Indigenous Spirituality, health, and well-being through Elder-governed yarns conducted via Zoom with 44 Aboriginal Elders, Healers, and Senior and Junior people involved in health and well-being of the Victorian Aboriginal community. These yarns were analyzed through an innovative, constructivist, multi-perspectival discursive grounded theory method. Key findings are that Spirituality is crucial for health and well-being, leading to a clear mind and at-peace "center" in a person. Aboriginal spiritual practices reflect the unique characteristics and essential rhythms of Country . Spiritual development is incremental and increases the obligations and responsibilities a person has to community and Country and leads to increased caring for Country . This paper provides rich detail about practical spiritual techniques to aid Indigenous young people and their kinship networks. It has the potential to shape future policy., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Biobased nylon (PA56) not only has the same physical properties as nylon (PA6/PA66) but its production method is also more environmentally friendly. PA56 fabric has the advantages of moisture absorption, perspiration, high-temperature resistance, and flexibility, which have been widely studied by scientific researchers. Wool has the advantages of beauty, environmental protection, and anti-wrinkle. However, pure wool fabrics have low strength and are easy to shrink when washed, which has always been a problem. Hence, this work adopted the ring spinning method to prepare wool/PA56 blended yarn with wool content of 0, 10, 30, 50, 70, and 100 wt%. Thus, to examine the effects of different blending ratios and twists on yarn performance, PA56 was blended with wool. The results showed that findings indicate that yarn performance is influenced by both yarn twist and blending ratio. The yarn thickens and takes on more linear density as the blending ratio and yarn twist increase. As the wool ratio increases, the yarn's breaking stress and breaking strain decrease. It is obvious that the strength and elongation at break of pure PA56 yarn are 2.09 cN/Dtex and 33.92%, respectively. When the wool content was 100 wt%, the strength and elongation at break of the blended yarn were 0.66 cN/Dtex and 21.15%, respectively. With the amount of wool blending, the yarn hairiness index's H-value initially rises and subsequently falls. The percentage of blended wool reaches 50% at 2.14; less blending might exacerbate the yarn's stem, resulting in neps and unevenness features. The quality of the yarn improves as the blending percentage rises. The yarn has the advantages of resource saving, biodegradability, and environmental friendliness and has a broad application prospect in the automotive interior field.

Background: Indigenous people in Australia experience far poorer health than non-Indigenous Australians. A growing body of research suggests that Indigenous people who are strong in their cultural identity experience better health than those who are not. Yet little is known about how Indigenous people create and maintain strong cultural identities in the contemporary context. This paper explores how Indigenous people in south-eastern Australia create and maintain strong cultural identities to support their health and wellbeing., Methods: Data were collected from 44 Indigenous people living in the south-eastern Australian state of Victoria via yarning. Yarning is a cultural mode of conversation that privileges Indigenous ways of knowing, doing and being. Yarning participants were selected for their prominence within Victorian Indigenous health services and/or their prominence within the Victorian Indigenous community services sector more broadly. Due to the restrictions of COVID-19, yarns were conducted individually online via Zoom. Data were analysed employing constructivist grounded theory, which was the overarching qualitative research methodology., Results: All yarning participants considered maintaining a strong cultural identity as vital to maintaining their health and wellbeing. They did this via four main ways: knowing one's Mob and knowing one's Country; connecting with one's own Mob and with one's own Country; connecting with Community and Country more broadly; and connecting with the more creative and/or expressive elements of Culture. Importantly, these practices are listed in order of priority. Indigenous people who either do not know their Mob or Country, or for whom the connections with their own Mob and their own Country are weak, may therefore be most vulnerable. This includes Stolen Generations survivors, their descendants, and others impacted by historical and contemporary child removal practices., Conclusions: The yarns reveal some of the myriad practical ways that Indigenous people maintain a strong cultural identity in contemporary south-eastern Australia. While programs designed to foster connections to Community, Country and/or Culture may benefit all Indigenous participants, those most disconnected from their Ancestral roots may benefit most. Further research is required to determine how best to support Indigenous Victorians whose connections to their own Mob and their own Country are unable to be (re)built., (© 2024. The Author(s).)

Mass transport in textiles is crucial. Knowledge of effective mass transport properties of textiles can be used to improve processes and applications where textiles are used. Mass transfer in knitted and woven fabrics strongly depends on the yarn used. In particular, the permeability and effective diffusion coefficient of yarns are of interest. Correlations are often used to estimate the mass transfer properties of yarns. These correlations commonly assume an ordered distribution, but here we demonstrate that an ordered distribution leads to an overestimation of mass transfer properties. We therefore address the impact of random ordering on the effective diffusivity and permeability of yarns and show that it is important to account for the random arrangement of fibers in order to predict mass transfer. To do this, Representative Volume Elements are randomly generated to represent the structure of yarns made from continuous filaments of synthetic materials. Furthermore, parallel, randomly arranged fibers with a circular cross-section are assumed. By solving the so-called cell problems on the Representative Volume Elements, transport coefficients can be calculated for given porosities. These transport coefficients, which are based on a digital reconstruction of the yarn and asymptotic homogenization, are then used to derive an improved correlation for the effective diffusivity and permeability as a function of porosity and fiber diameter. At porosities below 0.7, the predicted transport is significantly lower under the assumption of random ordering. The approach is not limited to circular fibers and may be extended to arbitrary fiber geometries.

Self-powered fabric electronic devices are critical for next-generation wearable technologies, biomedical applications, and human-machine interfaces. The flexible magnetoelectric strategy is an emerging self-powered approach that can adapt to diverse environments and yield efficient electric outputs. However, there is an urgent need to develop a continuous manufacturing method for fabricating self-powered sensing magnetoelectric yarns with a high magnetic powder ratio and resistance to severe surroundings. In this study, we report particle flow spinning mass-manufactured magnetoelectric yarns for self-powered mechanical sensing. It has been shown that mechanical stretching/bending forces can be sensed and recognized by magnetoelectric yarns without an additional power supply. Through a combination of parameter optimization experiments and Maxwell modeling, we reveal the mechanism behind this mechanical-to-electric conversion capability. We further show that these self-powered sensing magnetoelectric yarns can monitor human motions after being attached to texture clothing. We expect that our results will stimulate further research on fabric electronics in a self-powered manner and will substantially advance the field.

Bloodstain pattern analysis (BPA) for stains found on non-porous surfaces has matured into a powerful forensic science tool based on fluid mechanics principles. The same cannot be said when bloodstains are found on porous substrates, such as textiles. This is partially due to the complex nature of textiles with tens of thousands of different materials in addition to unknown wear characteristics. In this study, three single jersey knit fabrics were manufactured from 100% cotton ring-spun yarns of linear densities of 12, 20, and 30 Ne (492, 295, and 197 dtex, respectively) and nearly identical twist multipliers. Single drops of porcine blood of 2, 10, 30, and 60 µL were allowed to fall 1 cm (to eliminate the impact of blood velocity) onto each fabric to understand the effects of yarn size on wicking and bloodstains. The size of the stain was then measured and compared for different fabrics and blood drop sizes. Wicking of blood into the fabric was fastest for the largest yarn fabrics, but more extensive wicking occurred on finer yarn fabrics resulting in much larger stains. All stains were highly altered due to wicking of blood. The findings from this paper might help the forensic scientists in understanding wicking in textiles and comparing stains on different textiles to gain a better understanding of bloodstains on textiles., (© 2021 American Academy of Forensic Sciences.)

Nanofibre membranes produced through the electrospinning process have been studied extensively over the past decade for a number of high demand applications including use as tissue engineered scaffolds. Despite possessing desirable properties including high surface area to volume ratios and enhanced mechanical properties, they ultimately suffer from a lack of cellular infiltration. Variations on the process include the production of highly aligned filaments of electrospun fibres referred to as bundles and yarns. Nanofibre bundle and yarn-based scaffolds have been shown to demonstrate superior cell infiltration rates compared to traditional electrospun nonwovens while also offering the capability to be incorporated into a wider array of post-processing technologies. In this review, fibre collection techniques currently employed within the literature for the fabrication of electrospun bundles and yarns along with their applications in the field of tissue engineering will be discussed.

Lightweight artificial muscle fibers that can match the large tensile stroke of natural muscles have been elusive. In particular, low stroke, limited cycle life, and inefficient energy conversion have combined with high cost and hysteretic performance to restrict practical use. In recent years, a new class of artificial muscles, based on highly twisted fibers, has emerged that can deliver more than 2,000 J/kg of specific work during muscle contraction, compared with just 40 J/kg for natural muscle. Thermally actuated muscles made from ordinary polymer fibers can deliver long-life, hysteresis-free tensile strokes of more than 30% and torsional actuation capable of spinning a paddle at speeds of more than 100,000 rpm. In this perspective, we explore the mechanisms and potential applications of present twisted fiber muscles and the future opportunities and challenges for developing twisted muscles having improved cycle rates, efficiencies, and functionality. We also demonstrate artificial muscle sewing threads and textiles and coiled structures that exhibit nearly unlimited actuation strokes. In addition to robotics and prosthetics, future applications include smart textiles that change breathability in response to temperature and moisture and window shutters that automatically open and close to conserve energy., Competing Interests: Provisional patent 62/371,744, “Twisted, plied, uniformly coiled, and non-uniformly coiled artificial muscles for textile applications,” was filed on August 6, 2016.

Drug-coated sutures are widely used as delivery depots for antibiotics and anti-inflammatory drugs at surgical wound sites. Although drug-laden coating provides good localized drug concentration, variable loading efficiency and release kinetics limits its use. Alternatively, drug incorporation within suture matrices is hampered by the harsh fabrication conditions required for suture-strength enhancement. To circumvent these limitations, we fabricated mechanically robust electrospun core-sheath yarns as sutures, with a central poly-l-lactic acid core, and a drug-eluting poly-lactic-co-glycolic acid sheath. The electrospun sheath was incorporated with aceclofenac or insulin to demonstrate versatility of the suture in loading both chemical and biological class of drugs. Aceclofenac and insulin incorporated sutures exhibited 15% and 4% loading, and release for 10 and 7 days, respectively. Aceclofenac sutures demonstrated reduced epidermal hyperplasia and cellularity in skin-inflammation animal model, while insulin loaded sutures showed enhanced cellular migration in wound healing assay. In conclusion, we demonstrate an innovative strategy of producing mechanically strong, prolonged drug-release sutures loaded with different classes of drugs.

The present study describes a unique way of integrating substrateless electrospinning process with textile technology. We developed a new collector design that provided a pressure-driven, localized cotton-wool structure in free space from which continuous high strength yarns were drawn. An advantage of this integration was that the textile could be drug/dye loaded and be developed into a core-sheath architecture with greater functionality. This method could produce potential nanotextiles for various biomedical applications.