Wearable electronic textiles are used in sensors, energy-harvesting devices, healthcare monitoring, human–machine interfaces, and soft robotics to acquire real-time big data for machine learning and ...artificial intelligence. Wearability is essential while collecting data from a human, who should be able to wear the device with sufficient comfort. In this study, reduced graphene oxide (rGO) and silver nanowires (AgNWs) were supersonically sprayed onto a fabric to ensure good adhesiveness, resulting in a washable, stretchable, and wearable fabric without affecting the performance of the designed features. This rGO/AgNW-decorated fabric can be used to monitor external stimuli such as strain and temperature. In addition, it is used as a heater and as a supercapacitor and features an antibacterial hydrophobic surface that minimizes potential infection from external airborne viruses or virus-containing droplets. Herein, the wearability, stretchability, washability, mechanical durability, temperature-sensing capability, heating ability, wettability, and antibacterial features of this metallized fabric are explored. This multifunctionality is achieved in a single fabric coated with rGO/AgNWs via supersonic spraying.
Reduced graphene oxide (rGO) decorated with tin oxide (SnO2) is deposited on a fabric via supersonic spraying to produce wearable supercapacitor textiles. rGO improves the electrical conductivity of ...textiles, while SnO2 provides energy storage capabilities. The synergetic effect of the combination of rGO and SnO2 on the overall electrochemical performance of the supercapacitor was studied by varying the SnO2 concentration. The intermixed rGO flakes and SnO2 nanoparticles enhanced the charge transport within the composite electrode, ultimately improving the overall electrochemical performance. The porous structure of the fabric enables sufficient electrolyte diffusion into the deposited rGO and SnO2, to promote the interfacial activity between the active electrode and electrolyte. The optimal sample exhibited the highest specific capacitance of 1008 mF⋅cm−2 at a current loading of 1.5 mA⋅cm−2, with a capacitance retention of 93% after 10,000 cycles. Stretching and relaxing cyclic tests up to N = 1100 demonstrate the mechanical durability of the wearable supercapacitor. These promising results confirm that supersonic spraying is suitable for producing energy storage devices on wearable fabrics.
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•Wearable supercapacitors comprising reduced graphene oxide and tin oxide were fabricated.•The intermixed rGO flakes and SnO2 nanoparticles enhanced the charge transport.•The optimal sample exhibited the highest specific capacitance of 1008 mF cm−2 at a current loading of 1.5 mA cm−2.•The capacitance retention of 93% after 10,000 cycles was obtained.•Bending cycles up to N = 1100 demonstrated the mechanical durability of the wearable supercapacitor.
We demonstrate electrospun ternary Fe2O3-SnOx-carbon nanofiber (CNF) composites as high-performance, flexible, and freestanding anodes for Li ion batteries (LIBs). In the ternary composites, the CNF ...matrix accommodates volume changes of Fe and Sn during lithiation and delithiation, while also providing short Li ion diffusion pathways, which ultimately enhances the capacity of the LIB. The concentrations of Fe and Sn were varied to find the optimal composition. Higher Sn content increased capacity at slow discharge rates, but decreased capacity at higher discharge rates. Increasing Fe to Sn ratio improved performance at high discharge rates. The Fe2O3-SnOx-CNF composite fabricated at a Fe:Sn weight ratio of 3:1 exhibited a reversible capacity value of 756 mAh·g−1 after 55 cycles. The materials and methods demonstrated here are unique in producing a flexible, free-standing mat with high gravimetric capacity using a simple and scalable production process.
•Freestanding, flexible Fe2O3-SnOx-CNF mats were fabricated by electrospinning.•The optimized concentrations of Fe2O3 and SnOx presented to get higher capacity.•A reversible capacity of CNF with 3:1 Fe:Sn ratio is 756 mAh·g−1 after 55 cycles.•The 3:1 Fe:Sn ratio shows high capacity of 540 mAh·g−1 at 1A·g−1 current rate.
Whether clinically stable small abdominal aortic aneurysms should be surgically repaired or monitored with periodic noninvasive imaging is controversial. This study compared the two approaches in ...patients with aneurysms 4.0 to 5.4 cm in diameter. After a mean follow-up of nearly five years, there was no survival advantage associated with immediate surgical repair.
This study compared the two approaches in patients with aneurysms of 4.0 to 5.4 cm. There was no survival advantage with immediate surgical repair.
Each year in the United States, 9000 deaths result from rupture of abdominal aortic aneurysms.
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Another 33,000 patients undergo elective repair of asymptomatic abdominal aortic aneurysms to prevent rupture, which results in 1400 to 2800 operative deaths.
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,
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Because most abdominal aortic aneurysms never rupture,
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elective repair is undertaken only when the risk of rupture is considered high. The strongest known predictor of rupture is the maximal diameter of the aneurysm.
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,
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Elective repair has been recommended for patients with aneurysms of 4.0 cm or more in diameter who do not have medical contraindications,
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although others have advocated the use . . .
Reduced graphene oxide (rGO), carbon nanotubes (CNTs), and copper nanoparticles were supersonically sprayed onto a fabric to yield a wearable energy storage device with multifunctional sensing ...capabilities. This wearable electronic device is superhydrophobic and antibacterial, demonstrating its suitability for smart sportswear, futuristic military uniforms, healthcare monitoring, human-machine interfaces, and intelligent soft robotics. Both rGO and the CNTs contribute to the double-layer capacitance properties, owing to the accumulation of electrostatic charges, whereas copper enhances the charge transfer and pseudocapacitance via redox reactions with the electrolyte. The fabric is bendable, stretchable, and durable with respect to external mechanical stress. Because of the supersonic impact during coating, the deposited materials adhere well to the fabric surface to retain the durable mechanical properties. The rGO/CNT/Cu-coated fabric produced thermal energy by Joule heating upon application of an electrical voltage. This metallized fabric is also capable of sensing the surrounding temperature and variations in the external strain. The antibacterial properties of the fabric ensure that harmful microorganisms are destroyed, potentially preventing the spread of disease. All of these unique properties of the metallized fabric make it suitable for use in future electronic textiles, which are useful for energy-storing, heating, sensing, water-repellent, and antiviral applications.
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•CNTs, rGO, and copper nanoparticles are sprayed onto a fabric.•This wearable fabric sensor is superhydrophobic and antibacterial.•The fabric can undergo Joule heating when electrical voltage was applied.•The fabric exhibits energy storage properties suitable for supercapacitors.
•Nickel nanocones and ZnO nanosheets were fabricated on wearable stretchable fabrics using electroplating.•The fabric exhibited supercapacitor properties and could be used as a heater and ...pressure/temperature sensors.•The fabric exhibited antibacterial properties with an inhibition rate of 100% against E. coli and S. aureus.
Herein, nickel nanocones and zinc oxide nanosheets were electroplated onto a fabric to produce multifunctional (wearable, stretchable, washable, hydrophobic, and antibacterial) materials with sensing, heating, and supercapacitive properties. All these functionalities are integrated into a one-layered fabric that can be used as a portable intelligent electronic textile for potential application in healthcare monitoring, smart sportswear, and energy storage. Electroplated nickel enhances the electrical conductivity and thus increases the electron charge transfer for supercapacitor applications. The integration of ZnO with the Ni-plated fabric provides pseudocapacitance via redox reactions with the electrolyte. The resistance of the Ni/ZnO fabric changes in response to external stimuli such as temperature and strain. When voltage is applied, the fabric generates heat through Joule heating, demonstrating its potential application as winter sportswear. The superior mechanical durability of the fabric was confirmed through bending and stretching tests. The hydrophobic surface prevents viruses contained in liquid droplets from infiltrating the fabric. In addition, bacterial growth is inhibited because of the antibacterial properties of the Ni/ZnO fabric and because of Joule heating. The one-layered fabric integrated with such multiple functionalities is expected to be applicable in the development of next-generation portable and wearable electronic textiles in various industries.
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Purpose: To assess the effects of age, gender, race, and body size on infrarenal aortic diameter (IAD) and to determine expected values for IAD on the basis of these factors.
Methods: Veterans aged ...50 to 79 years at 15 Department of Veterans Affairs medical centers were invited to undergo ultrasound measurement of IAD and complete a prescreening questionnaire. We report here on 69,905 subjects who had no previous history of abdominal aortic aneurysm (AAA) and no ultrasound evidence of AAA (defined as IAD ≥ 3.0 cm).
Results: Although age, gender, black race, height, weight, body mass index, and body surface area were associated with IAD by multivariate linear regression (all
p < 0.001), the effects were small. Female sex was associated with a 0.14 cm reduction in IAD and black race with a 0.01 cm increase in IAD. A 0.1 cm change in IAD was associated with large changes in the independent variables: 29 years in age, 19 cm or 40 cm in height, 35 kg in weight, 11 kg/m
2 in body mass index, and 0.35 m
2 in body surface area. Nearly all height-weight groups were within 0.1 cm of the gender means, and the unadjusted gender means differed by only 0.23 cm. The variation among medical centers had more influence on IAD than did the combination of age, gender, race, and body size.
Conclusions: Age, gender, race, and body size have statistically significant but small effects on IAD. Use of these parameters to define AAA may not offer sufficient advantage over simpler definitions (such as an IAD ≥3.0 cm) to be warranted. (J Vasc Surg 1997;26:595-601.)
BACKGROUND We previously reported the prevalence and associations of abdominal aortic aneurysm (AAA) in 73,451 veterans aged 50 to 79 years who underwent ultrasound screening. OBJECTIVE To understand ...the prevalence of and principal positive and negative risk factors for AAA, and to assess reproducibility of our previous findings. METHODS In the new cohort of veterans undergoing screening, 52,745 subjects aged 50 to 79 without history of AAA underwent successful ultrasound screening for AAA, after completing a questionnaire on demographics and potential risk factors. RESULTS We detected AAA of 4.0 cm or larger in 613 participants (1.2%; compared with 1.4% in the earlier cohort). The direction and magnitude of the important associations reported in the first cohort were confirmed. Respective odds ratios for the major associations with AAA for the second and for the combined cohorts were as follows: 1.81 and 1.71 for age (per 7 years), 0.12 and 0.18 for female sex, 0.59 and 0.53 for black race, 1.94 and 1.94 for family history of AAA, 4.45 and 5.07 for smoking, 0.50 and 0.52 for diabetes, and 1.60 and 1.66 for atherosclerotic diseases. The excess prevalence associated with smoking accounted for 75% of all AAAs of 4.0 cm or larger in the total population of 126,196. Associations for AAA of 3.0 to 3.9 cm were similar but tended to be somewhat weaker. CONCLUSIONS Our findings confirm our previous cohort findings. Age, smoking, family history of AAA, and atherosclerotic diseases remained the principal positive associations with AAA, and female sex, diabetes, and black race remained the principal negative associations.Arch Intern Med. 2000;160:1425-1430-->
We demonstrate electrospun ternary Fe2O3-SnOx-carbon nanofiber (CNF) composites as high-performance, flexible, and freestanding anodes for Li ion batteries (LIBs). In the ternary composites, the CNF ...matrix accommodates volume changes of Fe and Sn during lithiation and delithiation, while also providing short Li ion diffusion pathways, which ultimately enhances the capacity of the LIB. The concentrations of Fe and Sn were varied to find the optimal composition. Higher Sn content increased capacity at slow discharge rates, but decreased capacity at higher discharge rates. Increasing Fe to Sn ratio improved performance at high discharge rates. The Fe2O3-SnOx-CNF composite fabricated at a Fe:Sn weight ratio of 3:1 exhibited a reversible capacity value of 756 mAh·g-1 after 55 cycles. The materials and methods demonstrated here are unique in producing a flexible, free-standing mat with high gravimetric capacity using a simple and scalable production process.
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