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Carbon dots (CDs) are luminescent carbon nanoparticles with significant potential in analytical sensing, biomedicine, and energy regeneration due to their remarkable optical, physical, biological, and catalytic properties. In light of the enduring ecological impact of non-biomass waste that persists in the environment, efforts have been made toward converting non-biomass waste, such as ash, waste plastics, textiles, and papers into CDs. This review introduces non-biomass waste carbon sources and classifies them in accordance with the 2022 Australian National Waste Report. The synthesis approaches, including pre-treatment methods, and the properties of the CDs derived from non-biomass waste are comprehensively discussed. Subsequently, we summarize the diverse applications of CDs from non-biomass waste in sensing, information encryption, LEDs, solar cells, and plant growth promotion. In the final section, we delve into the future challenges and perspectives of CDs derived from non-biomass waste, shedding light on the exciting possibilities in this emerging area of research. [ABSTRACT FROM AUTHOR]

Silk fibroin (SF), a natural protein derived from silkworms, has emerged as a promising biomaterial due to its biocompatibility, biodegradability, degradation rate, and tunable mechanical properties. This review delves into the intrinsic attributes of SF that make it an attractive candidate for scaffold development in tissue engineering and regenerative medicine. The distinctiveness of this comprehensive review resides in its detailed exploration of recent advancements in the fabrication techniques of SF‐based fibrous scaffolds, namely electrospinning, freeze‐drying, and 3D printing. An in‐depth analysis of these fabrication techniques is conducted to illustrate their versatility in customizing essential scaffold characteristics, such as porosity, fiber diameter, and mechanical strength. The article meticulously discusses process parameters, advantages, and challenges of each fabrication technique, highlighting the innovative advancements made in the respective field. Furthermore, the review goes beyond fabrication techniques to provide an overview of the latest biomedical applications and research endeavors utilizing SF‐derived scaffolds. From nerve regeneration and wound healing to drug delivery, bone regeneration, and vascular tissue engineering, the diverse applications underscore the versatility of SF in adopting various biomedical challenges. Finally, the article emphasizes the need for standardized characterization techniques, scalable manufacturing processes, and long‐term in vivo studies. [ABSTRACT FROM AUTHOR]

Continuous monitoring of implanted vascular implants poses challenges due to the inherent toxicity and instability of contrast agents within the body. The use of biocompatible materials with radiopaque properties offers a solution for continuous monitoring of implanted artificial grafts together with early detection of vascular prosthesis dysfunction, which mitigates the risk of catastrophic failures from leakages or aneurysms. Here, we aimed to develop an artificial vascular graft with enhanced radiopacity to facilitate postsurgery monitoring. To achieve this goal, MXene (Ti3C2 nanosheets) was incorporated into poly-(methyl methacrylate) (PMMA)/polydimethylsiloxane (PDMS) nanofibers via an electrospinning technique, to enhance radiopacity without compromising biocompatibility. The integration of MXene into the nanofiber resulted in an increase in the hydrophilicity of the samples, leading to enhanced cell attachment. Microcomputed tomography imaging was used to verify the radiopacity properties of the samples, showing excellent contrast characteristics. The biocompatibility and hemocompatibility of the samples showed that 50 wt % MXene is the optimal concentration, demonstrating no cytotoxic effects. This is due to the encapsulation of MXene inside the PMMA/PDMS nanofibers preventing the interaction of MXene nanosheets with the physiological environment in vitro while maintaining their radiopacity. This approach herein holds promise as a platform for the long-term monitoring of implanted polymeric materials, thereby addressing a critical unmet need in the field. [ABSTRACT FROM AUTHOR]

Global warming is one of the alarming issues, which is impacting humans globally. It is preferred to adopt a lifestyle that promotes heat dissipation from the human body. One approach to cool a human body is improvement in personal apparel, which can help the human body to cool quickly. The required characteristic for cooling performance can be achieved by employing materials with excellent thermal conductivity. Nanodiamonds (ND) have exceptional thermal conductivity properties and can help overcome the poor thermal conductivity of fabrics. This manuscript presents a study on a one‐sided coated fabric where NDs are applied to the skin side of the fabric to promote heat dissipation toward the atmosphere while the other side of the fabric, exposed to the hot atmosphere, remains uncoated to delay the transfer of out from atmosphere to human body. ND was applied onto cotton fabric through electrospraying polyurethane (PU) and carboxylated ND (NDCOOH). Scanning electron microscope (SEM) and optical microscopy images indicated a homogeneous distribution of the sprayed ND/PU solution over the fabric surface. The samples were chemically analyzed by Fourier transform infrared spectroscopy (FTIR). The thermal resistance was measured by a sweating guarded hot plate (SGHP), which confirmed lower thermal resistance of fabric from the ND‐coated side to atmosphere as compared to control, and thermal resistance from the uncoated to atmosphere was the same for both controlled and treated samples. Similarly, thermal conductivity, radiant heat transfer, and infrared spectroscopy characterizations strengthened the findings of SGHP results. Real‐life simulated experiments were also conducted to verify the performance of developed samples. The electrosprayed samples also showed higher ultraviolet protection than the control sample. Air permeability and moisture absorption of the samples slightly decreased after applying the coating but remained within an acceptable range of comfortability. The developed fabric can promote energy conservation, as it will warm slowly but cool quickly. This allows home or office temperature setpoints for localized cooling to be 2–3°C lower with a projected energy savings between 20% and 30%. [ABSTRACT FROM AUTHOR]

At present, peripheral nerve injuries (PNIs) are one of the leading causes of substantial impairment around the globe. Complete recovery of nerve function after an injury is challenging. Currently, autologous nerve grafts are being used as a treatment; however, this has several downsides, for example, donor site morbidity, shortage of donor sites, loss of sensation, inflammation, and neuroma development. The most promising alternative is the development of a nerve guide conduit (NGC) to direct the restoration and renewal of neuronal axons from the proximal to the distal end to facilitate nerve regeneration and maximize sensory and functional recovery. Alternatively, the response of nerve cells to electrical stimulation (ES) has a substantial regenerative effect. The incorporation of electrically conductive biomaterials in the fabrication of smart NGCs facilitates the function of ES throughout the active proliferation state. This article overviews the potency of the various categories of electroactive smart biomaterials, including conductive and piezoelectric nanomaterials, piezoelectric polymers, and organic conductive polymers that researchers have employed latterly to fabricate smart NGCs and their potentiality in future clinical application. It also summarizes a comprehensive analysis of the recent research and advancements in the application of ES in the field of NGC. [ABSTRACT FROM AUTHOR]

Zein, which accounts for around 80% of the total protein composition in corn, is a biocompatible and biodegradable substance derived from renewable sources. Although insoluble in water, its amphiphilic characteristics are utilized to generate nanoparticles, nanofibers, microparticles, and even films. Numerous recent studies have demonstrated the potential of zein as a prospective biomaterial to develop fibrous scaffolds for biomedical functions owing to its biocompatibility, fibrous formation, and encapsulating qualities. Fabrication of zein‐based fibrous scaffolds for biomedical applications is achieved by a wide variety of techniques, including electrospinning, wet spinning, freeze drying, and additive manufacturing. This article overviews current advancements in manufacturing techniques for zein‐based fibrous scaffolds. In addition, it summarizes the most recent biomedical applications and research activities utilizing zein‐based fibrous scaffolds. Overall, zein is proposed as a potential biomaterial for the production of fibrous scaffolds that stimulate cell adhesion and proliferation in a number of exciting biomedical applications due to its biodegradability, biocompatibility, and other unique features related to its structure. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) based hernia mesh often shows multiple post‐surgery complications due to lack of biocompatibility, poor cell attachment, and unwanted tissue adhesion. These limitations can be addressed by material designing and surface modification of a mesh with side‐specific properties such as the visceral side (facing intestine) with low protein and cell attachment and the parietal side (facing incision) with improved cell attachment properties for normal healing. However, the development of dual‐sided mesh is very challenging because of its porous structure. Herein, a dual‐sided biocompatible mesh with protein anti‐adsorption and cell attachment properties on two different sides is developed by grafting highly hydrophilic 2‐methcryloyloxyethyl phosphorylcholine polymer (PMPC) on the plasma‐activated visceral side, while the parietal side is coated with bioactive chitosan and functionalized nanodiamond (Chi/FND) using a temporary polyvinyl alcohol (PVA) mold. The PMPC‐grafted side demonstrated excellent resistance to protein adsorption (96% reduction compared to PP) and cell attachment. However, the bioactive coating on the parietal side has significantly improved cell attachment and proliferation properties. In addition, both sides confirmed the presence of the respective biomaterials after an accelerated degradation study for 28 days. Hence, the newly developed dual‐sided mesh by semi‐solid polymer mold (SSPM) method is a promising candidate to address the long‐existing multiple issues of hernia mesh. [ABSTRACT FROM AUTHOR]

ZnO nanoparticles (NPs) show remarkable efficiency in removing various contaminants from aqueous systems. Doping ZnO NPs with a second metal element can dramatically change the physicochemical properties of the pristine nanoparticles. However, there have been limited reports on the absorption of doped ZnO NPs, especially comparing the performance of ZnO NPs with different doping elements. Herein, ZnO NPs were doped with three transitional metals (Co, Fe, and Mn) at a nominal 2 wt.%. The particle surface had a higher dopant concentration than the interior for all NPs, implying the migration of the dopants to the surface. Because doping atoms inhibited grain growth, the doped ZnO NPs had a small particle size and a large surface area. The adsorption performance followed the order of Fe-doped < undoped < Mn-doped < Co-doped ZnO. Co-doped ZnO had an increased surface area and less tendency to agglomerate in an aqueous solution, showing the best adsorption performance. The adsorption of Congo red (CR) on Co-doped ZnO followed the pseudo-second-order model and the Langmuir isotherm. The adsorption process was spontaneous through monolayer chemisorption, and the maximum adsorption capacity was 230 mg/g. Finally, the Co-doped ZnO was successfully incorporated into an alginate membrane by electrospinning. The membrane demonstrated excellent adsorption performance and had great potential as an innovative and low-cost adsorbent (inexpensive raw materials and simple processing) for wastewater purification. [ABSTRACT FROM AUTHOR]

Three types of textile fabric waste, namely Kevlar, Nomex, and Cordura Nylon, were investigated in this study. The effects of the fiber parameters: volume fraction (0.1%, 0.3%, and 0.5%), length (6, 12, and 24 mm), and use of 1D fiber (width of 0) versus 2D woven fabric fiber (width of 3 and 6 mm) on strength properties, flowability, and shrinkage were studied to determine the optimum textile parameters. The pore structure, microstructure, and fiber-matrix interfacial properties of the optimised mixtures were then characterized by means of X-ray micro-CT, SEM, and nanoindentation at 7, 28, and 90 days. Results showed that the optimized parameters for three types of fabric fibers are 1D fiber (width of 0), length of 12 mm, and volume fraction of 0.3%. This optimized design provided an enhancement of strength and shrinkage resistance. Pore refinement was pronounced in the case of hydrophilic Kevlar and Nomex fibers. However, this also correlates to inferior performance in shrinkage resistance of mortar compared to hydrophobic Cordura Nylon. The fiber-matrix ITZ thickness was dependent on fiber size, while the wettability of fibers (i.e., hydrophobicity or hydrophilicity) was observed to affect the phase distribution in the vicinity of the fiber surface. Furthermore, a large volumetric proportion of the structure is porous in nature (more than 50%) in the region of the fiber-matrix interface after 7 days. With the increment of curing age, the microstructure at the fiber interface becomes denser due to the hydration of the clinker phase facilitating the growth of CSH and CH phases. [ABSTRACT FROM AUTHOR]

In this study, carpet waste fibers--namely, polypropylene (PP) and polytrimethylene terephthalate (PTT) in the form of mono microfibers and hybrid combinations--were studied. The optimization of mono fiber parameters for fiber content (0.1, 0.3, and 0.5%) and length (6, 12, and 24 mm [0.236, 0.742, and 0.945 in.]) were conducted to achieve the optimum strength properties and minimize drying shrinkage. The microstructure, pore structure, and fiber-matrix interfacial properties of the optimized samples were characterized at 7, 28, and 90 days by means of scanning electron microscopy (SEM), X-ray micro-computed tomography (CT), and nanoindentation. The research data revealed that the inclusion of either the optimized mono PP fiber (υf = 0.5% and l = 12 mm [0.472 in.]) or PTT fiber (υf = 0.1% and l = 12 mm [0.472 in.]) improved the compressive strength of 4.3% and 16.1%, and the flexural strength by 11.5% and 9.2% at 28 days, respectively. Hybrid carpet fibers (0.4% PP + 0.1% PTT) provided a greater enhancement in compressive strength of 6.6%, and flexural strength by 13% at 28 days. Drying shrinkage mitigation of mortar over 120 days was recorded as 18.4, 22.3, and 25.8%, corresponding to the addition of 0.5% PP fibers, 0.1% PTT fibers, and hybrid PP/PTT carpet fibers. A pore-refining effect was also observed for mortars with 0.5% PP and hybrid PP/PTT carpet microfibers. The SEM images indicated that the trilobal cross-sectional shape of PTT carpet fibers had a stronger anchoring effect with cement hydrates than the rounded shape of PP carpet fibers. Nanoindentation identified the thickness of the fiber-matrix interfacial transition zone (ITZ) as approximately 15 µm (5.9 × 10-4 in.) for both mono PP and PTT fibers. Approximately 50% of the phases in the vicinity of the fiber-matrix interface comprised a porous structure at 7 days. However, the hydration of clinker over the 90-day period promoted the formation of calcium-silicate-hydrate (C-S-H) and portlandite to form a dense microstructure. [ABSTRACT FROM AUTHOR]

The work describes the design, manufacturing, and user interface of a thin-film gas transducer platform that is able to provide real-time detection of toxic vapor. This proof-of-concept system has applications in the field of real-time detection of hazardous gaseous agents that are harmful to the person exposed to the environment. The small-size gas sensor allows for integration with an unmanned aerial vehicle, thus combining high-level mobility with the ability for the real-time detection of hazardous/toxic chemicals or use as a standalone system in industries that deal with harmful gaseous substances. The sensor was designed based on the ability of thin-film metal oxide sensors to detect chlorine gas in real time. Specifically, a concentration of 10 ppm of Cl2 was tested. [ABSTRACT FROM AUTHOR]

The development of cooling textiles has a significant impact on energy saving and cost‐effectiveness in the context of global warming. Engineering textiles with cooling performance while maintaining their intrinsic traits, for example, lightweight, washable, comfort, and durability, is a great challenge in developing personal cooling garments. Here, the synthesis of nanodiamond/polydopamine/wool (ND‐PDA‐wool) nanocomposites through a facile dip‐coating approach is demonstrated. Different types of ND including detonation ND (DND), carboxylated ND (ND‐COOH) and hydroxylated ND (ND‐OH), are used, and dopamine templating is applied to achieve strong adhesion and bonding between fiber and ND. The morphology, structure, and properties of the as‐coated fabrics are characterized, and the cooling performance together with comfort are measured. Due to the excellent thermal conductivity of ND, the temperature difference between the coated fabrics and uncoated ones is around 2.4–3.9 °C within a short time span of 30 min. The coated ND‐PDA‐Wool fabrics demonstrated enhanced thermal stability and improved mechanical properties with excellent durability, and the water absorbency is greatly enhanced with well‐maintained air permeability. ND‐PDA‐wool composite fabrics offer a strategy to develop durable, lightweight, washable, and comfortable cooling textiles with immense potential in energy saving and reducing space cooling costs. [ABSTRACT FROM AUTHOR]

Gallium and its alloys, such as eutectic gallium indium alloy (EGaIn), a form of liquid metal, have recently attracted the attention of researchers due to their low toxicity and electrical and thermal conductivity for biomedical application. However, further research is required to harness EGaIn‐composites advantages and address their application as a biomedical scaffold. In this research, EGaIn‐polylactic acid/polycaprolactone composites with and without a second conductive filler, MXene, were prepared and characterized. The addition of MXene, into the EGaIn‐composite, can improve the composite's electrochemical properties by connecting the liquid metal droplets resulting in electrically conductive continuous pathways within the polymeric matrix. The results showed that the composite with 50% EGaIn and 4% MXene, displayed optimal electrochemical properties and enhanced mechanical and radiopacity properties. Furthermore, the composite showed good biocompatibility, examined through interactions with fibroblast cells, and antibacterial properties against methicillin‐resistant Staphylococcus aureus. Therefore, the liquid metal (EGaIn) polymer composite with MXene provides a first proof‐of‐concept engineering scaffold strategy with low toxicity, functional electrochemical properties, and promising antimicrobial properties. [ABSTRACT FROM AUTHOR]

The deposition of textile waste into landfill has reached an unsustainable level and raises serious environmental issues across the world. Transforming textile waste into fiber reinforcement in cementitious composites offers a sustainable resolution toward a circular textile economy. This article presents a comprehensive review of environmental concerns, recycling routes for textile waste, together with an in-depth review of the engineering properties of concrete incorporating recycled textiles. In general, the incorporation of these recycled fibers from textile waste enhances strain capacity, crack control, durability, and energy absorption of concrete via dual effects: bridging action (direct mechanism) and refinement of pore distribution (indirect effect). An improvement in compressive strength can be achieved by the utilization of a small dosage of recycled fibers or recycled fiber fabrics in concrete (strength < 40 MPa). Finally, the cost and environmental benefits for eco-efficient building application are also evaluated to draw the attention of researchers toward these potentially recyclable waste materials. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) mesh is most commonly used for the treatment of hernia and pelvic floor construction. However, some of the patients have a few complications after surgery due to the rejection or infection of the implanted meshes. The poor biocompatibility of PP mesh, low wettability results in poor cell attachment/proliferation and restricts the loading of antibacterial agent, leading to a slow healing process and high risk of infection after surgery. Here in this study, a new technique has been employed to develop a novel antimicrobial and biocompatible PP mesh modified with bioactive chitosan and functionalized nanodiamond (FND) for infection inhibition and acceleration of the healing process. An oxygen plasma treatment PP mesh was used then chitosan was strongly attached to the surface of the PP fibers. Subsequently, FND as an antibacterial agent was loaded into the chitosan modified PP fiber to provide desired antibacterial functions. The meshes were characterised with XRD, FTIR, SEM, EDX, water contact angle, confocal, and optical microscopy. The modified PP mesh with chitosan and FND showed a significant increase in its hydrophilicity and L929 fibroblast cell attachment. Furthermore, the modified mesh exhibited great antibacterial efficiency against Escherichia coli. Therefore, the newly developed technique to modify PP mesh could be a promising technique to generate a biocompatible PP mesh to accelerate the healing process and reduce the risk of infection after surgery. [ABSTRACT FROM AUTHOR]

The introduction of nanomaterials (NMs) to a fibrous substrate has expanded the spectrum of its applications to various fields of life such as construction, medicine, protection, and energy. These promising outcomes are driving scientists to further explore this area from various aspects, including the introduction of different classes of NMs, their application through numerous approaches, and the potential achievement of various properties. A diamond nanoparticle is a biocompatible material with extraordinary thermal, mechanical, chemical, and optical properties. Nanodiamond (ND) has been extensively studied for its composites with polymers, fabrication, properties, and applications. It was attempted to combine ND with fibrous materials in nanofiber, fiber, filaments, yarns, and fabric, which opened up a new potential application area of ND in textiles. The fabrication, surface characterization, properties, and application of ND with various forms of fibrous materials are outlined in this review, which could be useful for paving the way for researchers to take some advanced steps in this respect. [ABSTRACT FROM AUTHOR]

The biocompatibility of materials is the determining factor for them to be applied in biomedical areas. Nanodiamond (ND) has gained increasing interest in this area due to its biocompatibility, ease of surface functionalization and excellent mechanical performance. ND has been widely used to reinforce biopolymers, and the resultant biocomposites have found applications in bone tissue engineering, chemotherapeutic drug delivery, and wound healing. Fluorescent ND, when combined with biopolymers, is serving for bioimaging and sensing applications. Herein, we contribute a description of ND, recent trends in its adoption for biopolymers, functionalization methods, amalgamation techniques of ND with biopolymers, potential applications of these composites in the biomedical field and future perspectives. [ABSTRACT FROM AUTHOR]

Detonation nanodiamonds are gaining considerable research interest due to their superior hardness, excellent mechanical properties, large surface area and small size. Surface functionality of polymeric, fibrous materials and nanocomposites can be significantly improved by application of nanodiamonds. Although there has been some research on nanodiamonds in polymeric materials and composites available, research on fibrous materials, such as textiles, is limited. We investigated potential improvement in the properties of cotton materials after application of nanodiamonds. Nanodiamonds were applied to cotton fabric using a sustainable dip-coating laboratory technique, which was then characterized for improved functionality in such properties as strength, elongation, thermal stability and surface energy. It was observed that a surface coating of nanodiamonds enhanced the tensile strength of the cotton by 79%, without compromising the flexibility of the substrate significantly, due to the exceptional mechanical properties of the nanodiamond particles and strong bonding between fibers and yarns within the fabric. High thermal conductivity of the nanodiamonds resulted in increased thermal stability and a higher degradation temperature in the coated substrate, when compared with the uncoated cotton fabric. Scanning electron microscopy images indicated that the coated cotton fabric displayed a coarser surface than the uncoated fabric. Coated fabric also absorbed more energy than uncoated fabric during repeated deformation in abrasion testing, due to presence of nanodiamond which resulted in imporvement of abrasion resistance. [ABSTRACT FROM AUTHOR]

We aim to develop biocompatible silk dressings, integrated with temperature (nanodiamond) and pH (fluorescein) sensors, capable of monitoring early signs of infections and healing disruptions non-invasively via light-based measurements. These hybrid dressings have strong potential to bring a paradigm shift to the current wound management and care procedures. Introduction: Assessing wound repair requires the removal of dressings, which is painful and disruptive to healing and is based on subjective visual observation of the wound. Improving this process is crucial, as monitoring wound status could enable earlier interventions to reduce the complications that arise from wound infection. Measuring the temperature and pH of the wound surface can provide objective indicators of wound progression1,2. A clinically diagnosed wound infection elevates the temperature by 3-5° C compared to healthy skin1 and the pH of wound fluid rises2 prior to the onset of local infection. Alkaline wound pH enables the invasion of microorganisms, while an acidic wound environment aids healing through protease activity, increased oxygen release, and reduced microbial growth. Hence temperature and pH are useful and robust biomarkers that can provide real-time insights into the healing responses. Methods: Silk fibroin was obtained from B. mori silk cocoons. The extracted silk solution was mixed with nanodiamonds and electrospun into nanofibrous membranes. Confocal and wide field microscopes were used to perform temperature sensing (using green 532 nm excitation) and pH sensing (using blue 470 nm excitation). Human skin keratinocyte (HaCaT) cell lines were used to study cell growth for the hybrid membranes. The in vivo biocompatibility on wound healing was tested on 8-10-week-old C57BL/6J mice, using a murine model of wound healing4. Bacterial suspensions of P. aeruginosa ATCC 9721, E. coli ATCC 11775, and S. aureus CIP 68.5 were used to test the biocidal properties of the hybrid membranes. Results: We showed that electrospun silk membranes embedded with nanodiamond sensors could monitor temperature changes in the wound relevant range of 32-40 °C3. In vitro tests revealed that hybrid membranes enabled eukaryotic cell attachment and promoted healthy cell growth. Furthermore, the membranes were biocidal towards major skin wounds infecting bacteria, P. aeruginosa and E. coli. In an in vivo wound healing model, the hybrid membranes enabled wound healing and did not cause adverse effects on wound closure3. Moreover, the pH-sensitive fluorescein sensor can be encapsulated within a silk matrix to provide measurements of acidity or basicity in vivo5. Conclusions: In conclusion, multiple fluorescent sensors embedded in silk dressings can be used as a platform for biosensing as well as providing a network of fibres that support healthy wound healing processes. [ABSTRACT FROM AUTHOR]

This study evaluated the deterioration in thermo-mechanical and performance properties of the polyaramid and polybenzidimazole fabric used in firefighters' protective clothing after exposure to ultraviolet irradiation, and the effect of weathering. The performance of firefighters' protective clothing plays an important role in protection against heat and physical threats to firefighters. However, frequent exposure to heat and ultraviolet irradiation can deteriorate performance. Test results demonstrated a 79% drop in the residual strength of polybenzidimazole/Kevlar® fabric and a 51% drop in the residual strength of polyaramid (Nomex® IIIA). The results confirmed that heat accelerates the degradation of PBI, resulting in lower performance, an important consideration for firefighters' protective clothing. In this study, a new 'UVPro-Tex' sensor was developed, with the capability to record the amount of ultraviolet irradiation absorbed by the fabric. When the amount of the absorbed ultraviolet irradiation reaches a critical value, the sensor warns the wearer of the end-of-life of the garment. [ABSTRACT FROM AUTHOR]

This research investigated the transport properties (such as thermal resistance, water vapor resistance and air permeability), moisture management capacity and sensorial properties of some knitted structures of superabsorbent polyacrylate in order to explore their potential as next-to-skin layers in firefighters’ protective clothing in Australia. Test results using these fabrics were compared with the currently used next-to-skin woven fabric. Three different knitted structures (i.e. jersey, rib and interlock) were selected for the study in addition to the current woven fabric in use by Australian firefighters. It was observed that the knitted fabric samples of superabsorbent polyacrylate retained higher amounts of water compared to the fabric sample currently used in the firefighters’ clothing. However, the woven fabric sample dried at a faster rate. Hence, a blended fabric of polyacrylate with the current Nomex® fabric can help in higher sweat absorption and faster drying. The thermal and water vapor resistance of jersey fabric was the lowest, which may better facilitate the transfer of metabolic heat and vapor to the environment, resulting in better thermal comfort. Furthermore, all the fabric samples showed a low coefficient of friction (∼0.2), which indicated less tactile discomfort if the fabrics are worn as the next-to-skin layer in the firefighters’ clothing. The overall moisture management properties of the fabric samples were rated as fair to good. The findings of this research suggest that the superabsorbent material has the potential to be used in place of the existing next-to-skin layer of firefighters’ protective clothing, with better sweat absorption capacity and thermal comfort. [ABSTRACT FROM AUTHOR]

Firefighters are often exposed to high temperature environments which can lead to dehydration and high body temperatures. Consequently, a reduction in mental concentration and an increase in fatigue levels will occur. The aim of this study is to investigate the implementation of Phase Change Material (PCM) into firefighter internal clothing to improve thermal protection. Both organic and inorganic types of PCM have high heat absorbing capacity and therefore can be used as thermal energy storage to enhance firefighter's body cooling and thermal protection. Experimental prototypes were constructed using cotton drill shirts, cotton mesh pockets and PCM packaged into aluminium pouches. The selected type of PCM studied was of paraffin wax as organic PCM and Glauber's salt as inorganic PCM which were used to create samples to be tested under simulated conditions. To increase the thermal conductivity of PCMs, the addition of copper metal foam to the paraffin wax was also analysed. The results indicated that the copper foam was able to reduce the melting time whilst evenly distributing the heat. This paper will provide detailed thermal analysis of different category of PCM and comparison of their respective heat absorbing performance, to achieve maximum thermal protection for firefighters via fully passive cooling approach. This implementation of PCM based firefighting clothing will lead to an improvement in firefighter's cooling sensations, potentially increase their operation time, better mental concentration. [ABSTRACT FROM AUTHOR]

In this study, a new inner-layer fabric was developed with the use of superabsorbent fibre (SAF) or Coolmax® materials for firefighters' protective clothing. These materials have high water vapour absorption and wicking capacity to assist in better moisture management in the microclimate next to the skin, providing improved comfort to the wearer. Results obtained from the water absorption tests confirmed higher absorption. These new inner-layers were tested for thermophysiological comfort properties, such as thermal resistance, water vapour resistance and air permeability. The results indicated that it is possible to improve the comfort properties of the firefighters' protective clothing with the incorporation of SAF or Coolmax® materials into the inner-layer. However, the mechanical properties of the fabric were significantly reduced by the incorporation of these materials into the structure. The performance of all new inner-layer combinations in regard to heat resistance satisfied the requirements for AS/NZS 4967-2009 firefighter's protective clothing, which is essential for adequate protection. [ABSTRACT FROM AUTHOR]

This research investigated the effect of repeated laundering and dry-cleaning on the physical and thermophysiological comfort properties such as air permeability, water vapour resistance and thermal resistance of fabrics made of meta-aramid (Nomex®) fibre. Two different types of fabric were selected for the study and subjected to repeated laundering and dry-cleaning (1, 5 and 10 cycles), which is commercially used for the care and maintenance of these fabrics. The fabric thickness, areal density, thermal resistance and water vapour resistance values increased with the number of laundering cycles, whereas the air permeability decreased due to the fabric shrinkage and swelling. On the other hand, the thickness and air permeability of the dry-cleaned fabric samples increased with the number of cycles; while the water vapour resistance and thermal resistance decreased. The scanning electron microscopy images showed the structural changes as indicated by the longitudinal fibrillation in the fabrics subjected to laundering or dry-cleaning. [ABSTRACT FROM AUTHOR]

In the current study, we describe the synthesis, material characteristics, and cytocompatibility of conducting poly (ɛ-caprolactone) (PCL)-based nano-composite films. Electrically conducting carbon nano-fillers (carbon nano-fiber (CNF), nano-graphite (NG), and liquid exfoliated graphite (G)) were used to prepare porous film type scaffolds using modified solvent casting methods. The electrical conductivity of the nano-composite films was increased when carbon nano-fillers were incorporated in the PCL matrix. CNF-based nano-composite films showed the highest increase in electrical conductivity. The presence of an ionic solution significantly improved the conductivity of some of the polymers, however at least 24 h was required to absorb the simulated ion solutions. CNF-based nano-composite films were found to have good thermo-mechanical properties compared to other conducting polymer films due to better dispersion and alignment in the critical direction. Increased nano-filler content increased the crystallisation temperature. Analysis of cell viability revealed no increase in cell death on any of the polymers compared to tissue culture plastic controls, or compared to PCL polymer without nano-composites. The scaffolds showed some variation when tested for PC12 cell attachment and proliferation, however all the polymers supported PC12 attachment and differentiation in the absence of cell adhesion molecules. In general, CNF-based nano-composite films with highest electrical conductivity and moderate roughness showed highest cell attachment and proliferation. These polymers are promising candidates for use in neural applications in the area of bionics and tissue engineering due to their unique properties. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 853-865, 2016. [ABSTRACT FROM AUTHOR]

In this study the degradation of woven fabrics of meta-aramid and the blend of para-aramid and polybenzimidazole fibers when exposed to environmental conditions has been investigated under accelerated ageing conditions. Generally, these polymeric materials have been used for the outer layer of protective clothing, particularly for fire-fighting. The performance of these fabrics plays an important role in preventing burn-injuries to fire fighters. Frequent exposure of these materials to various environmental conditions (especially sunlight) can degrade the polymeric chain and affect their performance properties. Hence, the degradation of the fabrics has been studied in terms of loss of tensile and tear strength; reduction in abrasion resistance; and extension at break. It was observed that ultraviolet (UV) irradiation negatively impacted on the mechanical properties of both the polymeric materials significantly. This can be attributed to chemical changes in the polymeric chains due to the photo-oxidation of the polymer. Scanning electron microscopy images revealed surface decomposition of the filaments due to UV irradiation. Exposure of polybenzimidazole resulted in rapid loss of mechanical and chemical properties in comparison with meta-aramid. However, decomposition and degradation of polybenzidimazole was not statistically significant. [ABSTRACT FROM AUTHOR]

In this research, super absorbent materials were incorporated into the internal layer of the firefighters’ protective clothing with the aim of increasing absorption of sweat to improve the thermo-physiological comfort properties. The performance properties were evaluated following the standard test methods (ISO 6942:2002 and ISO 9151: 1995(E)) and the thermo-physiological comfort-related properties were evaluated by measuring the transport properties such as air permeability, water sorption and evaporation, thermal resistance and water vapour resistance of the fabric assemblies with super absorbent materials. The results indicated that it is possible to improve the comfort properties of the protective clothing by the incorporation of super absorbent materials into the internal layer. The use of super absorbent materials is likely to help in the absorption of sweat in higher amount and keeping the skin and internal microclimate dry, which in turn improves the comfort level. The performance properties of all the combinations satisfied the requirements for firefighter’s clothing as mentioned in AS/NZS 4967-2009. [ABSTRACT FROM PUBLISHER]

The use of appropriate protective clothing systems in high-risk environments is absolutely essential. Such protective clothing may not provide the desired wearer comfort due to the complexities associated with the system. These constraints are largely due to the multiple layers involved in the protective ensemble. Firefighters’ protective clothing systems, in particular, have limited or no water vapor permeability. This prevents evaporative heat loss and leads to thermal strain and sweat accumulation. This accumulated sweat on the skin and on the internal layer close to the body causes considerable discomfort to the user due to the sensation of wetness. Extensive research has been done to improve the comfort properties of such protective clothing. This research adds yet another dimension where a new inner-layer construction has been developed with high liquid and vapor-absorption capacity that could assist in keeping the moisture and vapor away from the skin and, in addition, retain a dry microclimate close to the skin. The developed materials were tested for their biophysical properties that included tests such as thermal and water vapor resistance, air permeability and moisture management properties. Experimental results in this study indicated that super-absorbent materials, when incorporated into a woven textile material, showed enhanced wearer comfort. It was observed that these super-absorbent materials have the capability to quickly wick the moisture away from the body and, in doing so, have the tendency to keep the skin dry. [ABSTRACT FROM PUBLISHER]

Preparation and characterization of novel composites, consisting of polypropylene (PP) fibres in a random poly(propylene-co-ethylene) (PPE) matrix, were investigated. These composites possess unique properties, due to chemical compatibility of the two polymers allowing creation of strong physico-chemical interactions and strong interfacial bonds. The difference between the melting temperatures of PP fibre and PPE was exploited in order to establish processing conditions for the composites. Suitable conditions were chosen so that the matrix was a liquid, to ensure good wetting and impregnation of the fibres, though the temperature must not be high enough to melt the fibres. The morphology of the composites was investigated using optical and scanning electron microscopy. Optical microscope images showed that transcrystallization of the matrix was observed on PP fibre surfaces. SEM photographs displayed a thin layer of matrix on the reinforcement, attributed to good impregnation and wetting of the fibres. Adhesion between PPE matrix and PP fibres was characterized using a microbond test inspired by a fibre pull-out technique. The results showed that adhesion was appreciably increased when PP fibres were used instead of glass fibres in the matrix. Nevertheless, thermal processing conditions of the composites caused reduction in mechanical behaviour of the reinforcement. [ABSTRACT FROM AUTHOR]

In this study, measures of the quality and availability of social supports were found to moderate risk for depression associated with a history of maltreatment and the presence of the short (s) allele of the serotonin transporter gene promoter polymorphism (5-HTTLPR) The present investigation (i) replicates research in adults showing that 5-HTTLPR variation moderates the development of depression after stress, (ii) extends the finding to children, and (ill) demonstrates the ability of social supports to further moderate risk for depression. Maltreated children with the s/s genotype and no positive supports had the highest depression ratings, scores that were twice as high as the non-maltreated comparison children with the same genotype. However, the presence of positive supports reduced risk associated with maltreatment and the s/s genotype, such that maltreated children with this profile had only minimal increases in their depression scores. These findings are consistent with emerging preclinical and clinical data suggesting that the negative sequelae associated with early stress are not inevitable. Risk for negative outcomes may be modified by both genetic and environmental factors, with the quality and availability of social supports among the most important environmental factors in promoting resiliency in maltreated children, even in the presence of a genotype expected to confer vulnerability for psychiatric disorder. [ABSTRACT FROM AUTHOR]