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Maneuver of conducting polymers (CPs) into lightweight hydrogels can improve their functional performances in energy devices, chemical sensing, pollutant removal, drug delivery, etc. Current approaches for the manipulation of CP hydrogels are limited, and they are mostly accompanied by harsh conditions, tedious processing, compositing with other constituents, or using unusual chemicals. Herein, a two-step route is introduced for the controllable fabrication of CP hydrogels in ambient conditions, where gelation of the shape-anisotropic nano-oxidants followed by in-situ oxidative polymerization leads to the formation of polyaniline (PANI) and polypyrrole hydrogels. The method is readily coupled with different approaches for materials processing of PANI hydrogels into varied shapes, including spherical beads, continuous wires, patterned films, and free-standing objects. In comparison with their bulky counterparts, lightweight PANI items exhibit improved properties when those with specific shapes are used as electrodes for supercapacitors, gas sensors, or dye adsorbents. The current study therefore provides a general and controllable approach for the implementation of CP into hydrogels of varied external shapes, which can pave the way for the integration of lightweight CP structures with emerging functional devices., (© 2024 Wiley‐VCH GmbH.)

Introduction: There was a radically changed in nursing education during the nationwide lockdown due to the COVID-19 outbreaks. The transition to remote learning stressed nursing students in many countries, particularly in Vietnam. However, there is still lacking a novel study to describe the mental characteristics of nursing students in detail., Objectives: To assess the mental health of nursing students, including stress, anxiety, and depression, and to identify the related factors to their mental health during the online study period because of the COVID-19 pandemic., Methods: A cross-sectional survey was conducted on 540 nursing students at Dong A university using a socio-demographic questionnaire, the Depression, Anxiety, and Stress Scale - 21 Items (DASS-21). Data were analyzed by descriptive statistics and tests, including Mann-Whitney, Kruskal-Wallis, and Spearman's correlation to identify the related factors., Results: In total 540 participants, nursing students reported stress (N  =  120, 22.2%), anxiety (n  =  195, 36.1%), and depression symptoms (n  =  135, 23.1%). There was a significant relationship between age, work status, married status, number of children, stress, anxiety, and depression (P < 0.01). In addition, our study showed a negative correlation between frequency of physical activity, perceived health and stress (r  =  -0.117; p < 0.01, r  =  -0.127, p < 0.01), anxiety (r  =  -0.133; p < 0.01, r  =  -0.112, p < 0.01), depression (r  =  -0.134; p < 0.01, r  =  -0.135, p < 0.01). A significant relationship was observed between e-learning space and Internet status with mental health (p < 0.05). Especially, there was no association between average online learning time, academic workload, stress, anxiety, and depression (p > 0.05). However, the authors found a positive association between perceived level of stress related to evaluative activities and stress, anxiety, depression (r  =  0.120, p < 0.01; r  =  0.089, p < 0.05; r  =  0.088, p < 0.05)., Conclusion: Nursing students suffered stress, anxiety, and depression during online learning due to the COVID-19 pandemic in the presence of some related factors. Therefore, this study may increase more attention of universities, families, and governments to reduce the stress of nursing students during distance education., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

Background: We aimed to determine the time interval between alfentanil and rocuronium administration, at a 50% probability of preventing pain-induced withdrawal movement from rocuronium injection (Time AR 50)., Methods: A total of 64 patients scheduled for general anesthesia were enrolled in this study (33 men and 31 women). Anesthesia was induced with target-controlled infusion of propofol, at an effect-site target concentration of 3 μg/mL. Then, alfentanil 15 μg/kg was injected for 30 s. After 60 s, rocuronium 0.6 mg/kg was administered to the first patient. The Dixon's up-and-down method was used to determine the time interval for each subsequent patient (interval of 5 s). Mean arterial pressure (MAP) and heart rate (HR) were recorded at three time points: T0, pre-induction; T1, before rocuronium injection; and T2, 1 min after rocuronium injection., Results: The Time AR 50 ± standard deviation (SD) was 5.6 ± 3.7 s and 21.9 ± 5.6 s in the male and female patients, respectively. Based on the probit regression, the Time AR 50 was 4.7 s (95% confidence interval [CI], 1.2-7.6 s) and 20.3 s (95% CI, 7.7-26.1 s) in the male and female patients, respectively. The Time AR 95 was 10.6 s (95% CI, 7.7-25.3 s) and 35.0 s (95% CI, 28.1-95.5 s) in the male and female patients, respectively, with significantly higher values in females than in males (P < 0.001). Compared with the T0, MAP and HR decreased significantly at T1 and T2 in both groups., Conclusion: The Time AR 50 required for preventing rocuronium-induced withdrawal movement were 4.7 s and 20.3 s in male and female patients, respectively., Trial Registration: This study was registered with the Chinese Clinical Trials Registry on April 7, 2021 (URL: http://www.chictr.org.cn . Registry number: ChiCTR2100045137 ) ., (© 2022. The Author(s).)

A major obstacle for the use of single-wall carbon nanotubes (SWCNTs) in electronic devices is their mixture of different types of electrical conductivity that strongly depends on their helical structure. The existence of metal impurities as a residue of a metallic growth catalyst may also lower the performance of SWCNT-based devices. Here, it is shown that by using silicon oxide (SiO x ) nanoparticles as a catalyst, metal-free semiconducting and metallic SWCNTs can be selectively synthesized by the chemical vapor deposition of ethanol. It is found that control over the nanoparticle size and the content of oxygen in the SiO x catalyst plays a key role in the selective growth of SWCNTs. Furthermore, by using the as-grown semiconducting and metallic SWCNTs as the channel material and source/drain electrodes, respectively, all-SWCNT thin-film transistors are fabricated to demonstrate the remarkable potential of these SWCNTs for electronic devices., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The growth of high-quality semiconducting single-wall carbon nanotubes with a narrow band-gap distribution is crucial for the fabrication of high-performance electronic devices. However, the single-wall carbon nanotubes grown from traditional metal catalysts usually have diversified structures and properties. Here we design and prepare an acorn-like, partially carbon-coated cobalt nanoparticle catalyst with a uniform size and structure by the thermal reduction of a [Co(CN)6](3-) precursor adsorbed on a self-assembled block copolymer nanodomain. The inner cobalt nanoparticle functions as active catalytic phase for carbon nanotube growth, whereas the outer carbon layer prevents the aggregation of cobalt nanoparticles and ensures a perpendicular growth mode. The grown single-wall carbon nanotubes have a very narrow diameter distribution centred at 1.7 nm and a high semiconducting content of >95%. These semiconducting single-wall carbon nanotubes have a very small band-gap difference of ∼0.08 eV and show excellent thin-film transistor performance.

The effect of sulfur on the catalytic nucleation and growth of single-wall carbon nanotubes (SWCNTs) from an iron catalyst was investigated in situ by transmission electron microscopy (TEM). The catalyst precursor of ferrocene and growth promoter of sulfur were selectively loaded inside of the hollow core of multiwall CNTs with open ends, which served as a nanoreactor powered by applying a voltage inside of the chamber of a TEM. It was found that a SWCNT nucleated and grew perpendicularly from a region of the catalyst nanoparticle surface, instead of the normal tangential growth that occurs with no sulfur addition. Our in situ TEM observation combined with CVD growth studies suggests that sulfur functions to promote the nucleation and growth of SWCNTs by forming inhomogeneous local active sites and modifying the interface bonding between catalysts and precipitated graphitic layers, so that carbon caps can be lifted off from the catalyst particle.

Objective: To investigate the effects of cardiopulmonary bypass on neutrophils apoptosis and the expression of survivin., Methods: Ten patients who scheduled for cardiac surgery under cardiopulmonary bypass were recruited as study group and 10 healthy volunteers as control. Blood samples were obtained before operation, at the end of surgery, and at 24 hours postoperatively. Neutrophils were isolated by density gradient centrifugation and its apoptosis were evaluated by fluorescent microscope and flow cytometry. The expression of survivin protein was examined by Western blotting analysis. Expression level of survivin mRNA was detected by RT-PCR., Results: The apoptotic rate of neutrophils decreased significantly at the end of surgery (P < 0.01), and was still lower at 24 hours postoperatively than before operation (P < 0.05). The expression ratios of survivin protein and mRNA were increased at the end of surgery (P < 0.01), and decreased gently at 24 hours postoperatively but was still higher than before operation (P < 0.05)., Conclusion: Cardiopulmonary bypass could inhibit neutrophils apoptosis and increase the expression of survivin. The decrease of neutrophils apoptosis was correlated with high expression of survivin.

Vertically aligned Mg-doped GaN nanorods have been epitaxially grown on n-type Si substrate to form a heterostructure for fabricating p-n heterojunction photovoltaic cells. The p-type GaN nanorod/n-Si heterojunction cell shows a well-defined rectifying behavior with a rectification ratio larger than 10(4) in dark. The cell has a high short-circuit photocurrent density of 7.6 mAlcm2 and energy conversion efficiency of 2.73% under AM 1.5G illumination at 100 mW/cm2. Moreover, the nanorod array may be used as an antireflection coating for solar cell applications to effectively reduce light loss due to reflection. This study provides an experimental demonstration for integrating one-dimensional nanostructure arrays with the substrate to directly fabricate heterojunction photovoltaic cells.

Masses of single-walled carbon nanotubes (SWNTs) with a large mean diameter of about 1.85 nanometers, synthesized by a semicontinuous hydrogen arc discharge method, were employed for hydrogen adsorption experiments in their as-prepared and pretreated states. A hydrogen storage capacity of 4.2 weight percent, or a hydrogen to carbon atom ratio of 0.52, was achieved reproducibly at room temperature under a modestly high pressure (about 10 megapascal) for a SWNT sample of about 500 milligram weight that was soaked in hydrochloric acid and then heat-treated in vacuum. Moreover, 78.3 percent of the adsorbed hydrogen (3.3 weight percent) could be released under ambient pressure at room temperature, while the release of the residual stored hydrogen (0.9 weight percent) required some heating of the sample. Because the SWNTs can be easily produced and show reproducible and modestly high hydrogen uptake at room temperature, they show promise as an effective hydrogen storage material.