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The development of a highly flexible, ultra-selective, and stable gas sensor is crucial in wearable electronic devices. Herein, carbon nanofibers (CNFs)/NiCo2O4 with different nanostructures were prepared and assembled as gas sensors for methanol detection. The CNFs/NiCo2O4 prepared by potassium permanganate treatment showed the highest gas sensitivity (0.1–100 ppm) and a good linear response. Meanwhile, the CNF/NiCo2O4 composite membrane sensors were tested after bending at different angles of 30°, 60°, and 90°. The response efficiencies could be maintained at 90.8%, 88.7%, and 87.1%, respectively, after 50 cycles, indicating that the sensors had good stability and flexibility. This approach provides a strategy for the controllable design and synthesis of homogeneous hierarchical CNF/transition metal oxide (TMO) composites for flexible gas sensor. [ABSTRACT FROM AUTHOR]

Background: Cancer threat is relevant to age, and the threat of a foreshortened life coupled with a lengthy treatment process negatively affects middle‐aged and older adults. Understanding the coping throughout the cancer experience in middle‐aged and older cancer survivors will help develop supportive care to promote their physiological and psychological coping effects. Objectives: To explore the cancer coping experiences of middle‐aged adults aged 40–59 and older adults over 60. Design: A descriptive phenomenological study was employed. Methods: Face‐to‐face, in‐depth, semistructured interviews were conducted with 22 oncology patients in a tertiary university hospital aged 40 or above from August to October 2023. The interview data were analyzed using thematic analysis procedures. Results: Five themes and 13 subthemes were formed through analysis: acceptance of cancer (considering cancer as chronic, believing in fate and attributing cancer to karma); having different information needs (desired to be truthfully informed, information‐seeking behaviour, information avoidance behaviour); getting families involved (developing dependent behaviours, feeling emotional support, family members suffering worse); striving to maintain positive psychological state (positive thinking, seeking peer support) and negative experience (undesirable, low self‐esteem). Conclusion: Our study reveals that cancer survivors' attitudes towards having cancer have changed from a death sentence to a more positive perception of a chronic disease. Supportive programmes for developing coping strategies should consider the cultural traditions and religious beliefs, different information needs, involvement of family and promoting a positive psychological state while avoiding negative factors. Patient or Public Contribution: Participants with experience of coping with cancer were involved in the semistructured interview. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is a chronic infectious disease caused by mycobacterium tuberculosis (Mtb) that poses a major threat to human health. Herein, we aim to review the alteration of the microbiota in gut and respiratory during TB development, the potential function and mechanisms of microbiota in the pathogenesis of Mtb infection, and the impact of antibiotic treatment on the microbiota. In addition, we discuss the potential new paradigm for the use of microbiota-based treatments such as probiotics and prebiotics in the treatment of TB. Studies have shown that trillions of micro-organisms live in the human gut and respiratory tract, acting as gatekeepers in maintaining immune homeostasis and respiratory physiology and playing a beneficial or hostile role in the development of TB. Anti-TB antibiotics may cause microecological imbalances in the gut and respiratory tract, and microbiome-based therapeutics may be a promising strategy for TB treatment. Appropriate probiotics and prebiotics supplementation, along with antimycobacterial treatment, will improve the therapeutic effect of TB treatment and protect the gut and respiratory microbiota from dysbiosis. [ABSTRACT FROM AUTHOR]

A novel self‐healing poly(vinyl alcohol) (PVA)‐based hydrogel is developed by cross‐linking PVA chains through multi dynamic covalent bonds by use of a small cross‐linker composed by 4‐formylphenylboric acid (FPBA) and lysine (Lys). The dynamic borate‐imine‐imine‐borate bond structure between PVA chains endows the hydrogel excellent stretchability and ultra‐fast self‐healing ability without external stimulation. The self‐healing efficiency can attain 94% and the elongation at break can reach up to near 1000% after only 3 min healing. Moreover, the self‐healing of the hydrogel through the contact of two faces from both the same cut position and different cut positions has similar excellent efficiency. The hydrogel with the unusual self‐healing performance and stretchability is used as an ideal material in strain sensors monitoring human movement and tiny vibrations caused by human voice. Interestingly, the sensor can continue to function normally after self‐healing for only ≈3 s. It is expected that this simple strategy of fabricating self‐healing hydrogels with multi dynamic bonds will provide new opportunities in the design and preparation of PVA‐based hydrogels to expand their potential applications in sensors and other various fields. [ABSTRACT FROM AUTHOR]

Poly(trimethylene terephthalate) (PTT) fibers have drawn much attention due to their excellent elastic recovery. Currently, PTT fibers with higher elasticity are in high demand in some special applications. In this article, in order to further improve the elasticity of PTT fibers, heat treatment with alternating tension and relaxation (AlterTR) was carried out, and as a comparison, heat treatments under the conditions of tension or relaxation were performed simultaneously. The relationships of conformation transition, crystallinity, and orientation with elastic recovery of heat treated PTT fibers were investigated. With the increase of crystallinity during the treatment, part of the higher‐energy trans conformation of the heat treated PTT fibers was converted to a lower‐energy gauche conformation, which is a primary cause of elastic recovery. AlterTR heat treated PTT fibers had both high crystallinity and high orientation, which resulted in a high elastic recovery of 79% at 30% fixed elongation after 5 cycles of stretching testing, 7% higher than untreated PTT fibers. The elastic recovery was also obviously higher than the PTT fibers heat treated under the conditions of tension or relaxation. [ABSTRACT FROM AUTHOR]

Aerogel fibers are thermally insulating and can be woven, so they are expected to form a new generation of smart textiles that can efficiently reduce heat consumption. However, producing continuous aerogel fibers that have the necessary strength and toughness to be woven remains a great challenge. Herein, with the aid of freeze‐thaw treatment of poly(vinyl alcohol) (PVA) solution and freeze‐spinning technology, continuous PVA aerogel fibers with an aligned porous morphology are prepared in a large‐scale. Freeze–thaw treatment greatly contributes to improving the spinnability of the spinning dope of aerogel fibers, which leads to the formation of the continuous fibers. Remarkably, through this process the aerogel fibers achieve ultraflexible and ultrastrong features, which results in excellent weaving ability, as well as attractive mechanical properties that benefit from the cross‐linking of PVA molecular chains with the aligned porous structure. More importantly, a textile woven with the special porous structure aerogel fibers shows extraordinary thermal insulation (thermal conductivity as low as 0.026 W m−1 K−1) and infrared stealth. This study illustrates a promising direction for the design of next generation, wearable, intelligent materials that have great potential for personal thermal management applications. [ABSTRACT FROM AUTHOR]

To assemble small nanoparticles into a hollow polyhedron superstructure as a sensing material is a promising approach to improve the performance of metal-oxide–semiconductor gas sensors. In this study, ZnCo2O4 hollow polyhedrons (ZnCo2O4 HP) assembled by small nanoparticle-building blocks were prepared by simple one-step calcination of ZIF-67/ZIF-8 composites. Benefiting from rich active sites and abundant oxygen defects, ZnCo2O4 HP exhibited high response (∼0.7 ppm−1) and low limits of detection (1 ppm) to ethanol vapor at a temperature of 200 °C compared with other similar ethanol sensors. The sensing mechanism was investigated to identify the underlying surface chemical processes in different atmospheres by operando near ambient pressure X-ray photoelectron spectroscopy (NAPXPS). The obtained spectral data indicated that oxygen adsorbed on the surface as active oxygen could react with ethanol molecules, which were decomposed into carboxylates. The present study provides strategies for the rational design of AB2O4 materials, as well as an advanced method for the study of its sensing mechanism. [ABSTRACT FROM AUTHOR]

Objectives: To explore the perceptions of patients undergoing percutaneous coronary intervention (PCI) regarding their pre‐operative health education. Methods: A qualitative study using semi‐structured, in‐depth interviews was conducted in one cardiology unit in China from July 2019 to December 2019. Purposeful sampling of 17 patients undergoing PCI was interviewed about their perceptions of pre‐operative health education. Thematic analysis of the transcribed data was then used to identify the themes. Results: Four themes emerged from the data:(a) triple roles of pre‐operative education with the categories of relief (reliving fear); burden (leading to stress); and meaningless (changing nothing); (b) family member involvement with the categories of shared responsibility and family members' duty; (c) facilitators in the process of pre‐operative health education with the categories of emotional support, plain language and individualized pre‐operative education; (d) inhibitors in the process of pre‐operative health education with the categories of contradiction and threatening words. Conclusions: Pre‐operative health education for patients undergoing PCI should be aligned with the individual patients' information‐seeking styles and personal differences, emphasizing individualized patient education. Traditional Chinese philosophy should be considered in the practice of pre‐operative education for patients undergoing PCI, which emphasizes family member involvement; at the same time, patient empowerment and self‐care should also be stressed. In addition, emotional support and plain language from health professionals are important in pre‐operative health education for patients undergoing PCI; contradiction should be avoided, and threatening words should be used with caution and with consideration for cultural variations during pre‐operative education for patients undergoing PCI. [ABSTRACT FROM AUTHOR]

This study introduces a facile method to prepare syndiotactic poly(vinyl alcohol) (s-PVA) fibers containing singlewalled carbon nanotubes (SWNTs) from the corresponding composite dispersions with tea polyphenols (TP) as dispersant under high-speed shear flow. The formation of the composite fibrous precipitates at high shear rate is largely facilitated by the SWNTs in the dispersions and slight flow resistance. Interestingly, the obtained s-PVA/SWNTs composite precipitates possess a three-level hierarchical structure, that is, a single fiber is assembled by fibrils which are composed of microfibrils of s-PVA-coated SWNTs. And the s-PVA fibrous precipitates containing high amounts of SWNTs could be obtained by shearing the dispersion with relatively low SWNTs loadings, as a result, the composite fiber containing 20.7 wt% SWNTs was prepared from the dispersion with 10.0 wt% SWNTs. In addition, with the increase of SWNTs loadings, the amount of the precipitates increases, but crystallinity of the precipitates decreases instead. [ABSTRACT FROM AUTHOR]

Abstract: The functionalized conductive polymer is a promising choice for flexible triboelectric nanogenerators (TENGs) for harvesting human motion energy still poses challenges. In this work, a transparent and stretchable wrinkled poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PEDOT:PSS) electrode based TENG (WP‐TENG) is fabricated. The optimum conductivity and transparency of PEDOT:PSS electrode can reach 0.14 kΩ □−1 and 90%, respectively, with maximum strain of ≈100%. Operating in single‐electrode mode at 2.5 Hz, the WP‐TENG with an area of 6 × 3 cm2 produces an open‐circuit voltage of 180 V, short‐circuit current of 22.6 µA, and average power density of 4.06 mW m−2. It can be worn on the wrist to harvest hand tapping energy and charge the capacitor to 2 V in ≈3.5 min, and then drive an electronic watch. Furthermore, the WP‐TENG as the human motion monitoring sensor could inspect the bending angle of the elbow and joint by analyzing the peak value of voltage and monitor the motion frequency by counting the peak number. The triboelectric mechanism also enables the WP‐TENG to realize high‐performance active tactile sensing. The assembled 3 pixel × 3 pixel tactile sensor array is fabricated for mapping the touch location or recording the shape of object contacted with the sensor array. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) aerogel with special porous structure can combine the advantages of its high adsorbability with excellent mechanical properties to show excellent performance in the capture of particulate matter smaller than 2.5 μm (PM2.5) and in the recycling of the aerogel. However, the fabrication of the aerogel with durable ordered large through-pores is challenging due to lack of an effective strategy to control the porous structure from the randomly arranged GO sheets. Herein, a facile fabrication strategy towards the stable honeycomb-like-structured GO aerogel, comprising large-sized GO sheets (LGO), via freeze casting with the help of the electrostatic field effect of tourmaline is reported. The added modified tourmaline nanoparticles (mTNPs) effectively reduce the repulsion between GO sheets and highly promote the ordered stacking of LGO sheets to form honeycomb-like-structured aerogel possessing stable large through-pores. Benefiting from its special porous structure, this hybrid aerogel exhibits superior adsorption for PM2.5 and superior recycling performance. When mTNPs loading is 5 wt%, the PM2.5 filtration efficiency of the aerogel is up to 95.1% in the first adsorption cycle, and more importantly, the aerogel can be used repeatedly and retain the high filtration efficiency after simple recycling. [ABSTRACT FROM AUTHOR]

To develop a green and efficient method to synthesize graphene in relative milder conditions is prerequisite for graphene applications. A chemical reducing method has been developed to high efficiently reduce graphene oxide (GO) using Fe2O3 and NH3BH3 as catalyst and reductants, respectively. During the process, environmental and strong reductive nascent hydrogen were generated surrounding the surface of GO sheets by catalyst hydrolysis reaction of NH3BH3 and were used for reduction of GO. The reduction process was studied by ultraviolet absorption spectroscopy, Raman spectroscopy, and Fourier transform infrared spectrum. The structure and morphology of the reduced GO were characterized with scanning electron microscopy and transmission electron microscopy. Compared to metal (Mg/Fe/Zn/Al) particles and acid system which also use nascent hydrogen to reduce GO, this method exhibited higher reduction efficiency (43.6%). Also the reduction was carried out at room temperature condition, which is environmentally friendly. As a supercapacitor electrode, the reversible capacity of reduced graphene oxide was 113.8 F g-1 at 1 A g-1 and the capacitance retention still remained at 90% after 200 cycles. This approach provides a new method to reduce GO with high reduction efficiency by green reductant. [ABSTRACT FROM AUTHOR]

Synthesizing graphene at a large-scale and of high quality on insulating substrate is a prerequisite for graphene applications in electronic devices. Typically, graphene is synthesized and then transferred to the proper substrate for subsequent device preparation. However, the complicated and skilled transfer process involves some issues such as wrinkles, residual contamination and breakage of graphene films, which will greatly degrade its performance. Direct synthesis of graphene on insulating substrates without a transfer process is highly desirable for device preparation. Here, we report a simple, transfer-free method to synthesize graphene directly on insulating substrates (SiO2/Si, quartz) by using a Cu layer, graphene oxide and Poly (vinyl alcohol) as the catalyst, seeds and carbon sources, respectively. Atomic force microscope (AFM), scanning electronic microscope (SEM) and Raman spectroscopy are used to characterize the interface of insulating substrate and graphene. The graphene films directly grown on quartz glass can attain a high transmittance of 92.8% and a low sheet resistance of 620 Ω/square. The growth mechanism is also revealed. This approach provides a highly efficient method for the direct production of graphene on insulating substrates. [ABSTRACT FROM AUTHOR]