Magnetic vortex configuration in Fe3O4 nanorings/nanotubes for aspect ratio and magnetic orientation regulated microwave absorption

Morphological structure can greatly affect the magnetic domain of magnetic materials, which plays a significant role on regulating the magnetic characteristics and electromagnetic properties. Herein, Fe3O4 nanorings/nanotubes with adjustable aspect ratio were fabricated through a hydrothermal route followed by reduction annealing treatment. The magnetic flux distributions in radial and axial direction were characterized by electron holography, suggesting that the Fe3O4 nanorings/nanotubes show magnetic vortex structure. The magnetic vortex-domain structure is favored to break the Snoek’s limit of Fe3O4, improving the high-frequency permeability and boosting the natural resonance band to 1 ∼ 10 GHz. Meanwhile the complex permittivity is highly sensitive to the aspect ratio. The Fe3O4 nanorings/nanotubes perform excellent comprehensive microwave absorption properties, owing to the special magnetic vortex structure, tunable complex permittivity, big complex permeability, large magnetization and high natural resonance. The Fe3O4 nanorings with the smallest aspect ratio show a minimum reflection loss (RL) value of −47.9 dB at 2.6 mm and EAB of 4 GHz at 3 mm. Besides, rotational orientation by an external magnetic field can cause the parallel arrangement of nanorings/nanotubes, which can increase both the complex permittivity and broad the resonance band. Rotational orientation can realize effective absorption efficiency at a broader frequency range with a thinner thickness, further improving the comprehensive microwave absorption. These findings not only suggest that designing particular magnetic-domain structures by morphologies can break the Snoek’s limit of magnetic materials, but also demonstrate that aspect ratio and magnetic field-assisted rotational orientation is promising ways to regulate the electromagnetic parameters, resulting in high-performance microwave absorption

Epidemiological Investigation and Genetic Analysis of Pseudorabies Virus in Yunnan Province of China from 2017 to 2021

In recent years, the prevalence of pseudorabies virus (PRV) has caused huge economic losses to the Chinese pig industry. Meanwhile, PRV infection in humans also sounded the alarm about its cross-species transmission from pigs to humans. To study the regional PRV epidemic, serological and epidemiological investigations of PRV in pig populations from Yunnan Province during 2017–2021 were performed. The results showed that 31.37% (6324/20,158, 95% CI 30.73–32.01) of serum samples were positive for PRV glycoprotein E (gE)-specific antibodies via enzyme-linked immunosorbent assay (ELISA). The risk factors, including the breeding scale and development stage, were significantly associated with PRV seroprevalence among pigs in Yunnan Province. Of the 416 tissue samples collected from PRV-suspected pigs in Yunnan Province, 43 (10.33%, 95% CI 7.41–13.26) samples were positive for PRV-gE nucleic acid in which 15 novel PRV strains from these PRV-positive samples were isolated, whose gC and gE sequences were analyzed. Phylogenetic analysis showed that all 15 isolates obtained in this study belonged to the genotype II. Additionally, the gC gene of one isolate (YuN-YL-2017) was genetically closer to variant PRV strains compared with others, while the gE gene was in the same clade with other classical PRV strains, indicating that this isolate might be a recombinant strain generated from the classical and variant strains. The results revealed the severe PRV epidemic in Yunnan Province and indicated that PRV variants are the major genotypes threatening the pig industry development

Facile Fabrication of Ultralow Density and Ultrahigh Solar Absorption Monolithic Phenolic Carbon Aerogel from Lignite for Solar Vapor Generation

Solar vapor generation has been recognized as one of the most sustainable desalination methods due to its high energy efficiency and zero carbon emissions. However, it is often limited by poor mechanical properties, a complex preparation process, and/or the high density of photothermal materials. Here, we present a simple and effective method for preparing high-strength lignite-based phenolic carbon aerogels (LPCAs) for seawater desalination. LPCAs were prepared using an ethanol-soluble portion (ESP) from lignite as the raw material and melamine as the skeleton by polymerization/gelation, vacuum-drying, and carbonization, avoiding the energy-intensive freeze-drying step. Due to the abundant alkyl side chains and condensed aromatics in the ESP, LPCA has an ultralow density (42 mg·cm–3) and ultrahigh light absorbance (97.3%) without the need of additional expensive photothermal materials. Moreover, LPCA can regulate the intermediate water content and absorb energy from the environment. Based on these advantages, the evaporation rate of the LPCA evaporator can reach up to 2.40 kg·m–2·h–1 under 1 sun with an energy efficiency of 93.5%. Additionally, LPCAs with high strength (4.48 MPa under 90% strain), self-floating, good salt resistance, and applicability under harsh conditions facilitate practical application for producing clean water

Facile Fabrication of Ultralow Density and Ultrahigh Solar Absorption Monolithic Phenolic Carbon Aerogel from Lignite for Solar Vapor Generation

Solar vapor generation has been recognized as one of the most sustainable desalination methods due to its high energy efficiency and zero carbon emissions. However, it is often limited by poor mechanical properties, a complex preparation process, and/or the high density of photothermal materials. Here, we present a simple and effective method for preparing high-strength lignite-based phenolic carbon aerogels (LPCAs) for seawater desalination. LPCAs were prepared using an ethanol-soluble portion (ESP) from lignite as the raw material and melamine as the skeleton by polymerization/gelation, vacuum-drying, and carbonization, avoiding the energy-intensive freeze-drying step. Due to the abundant alkyl side chains and condensed aromatics in the ESP, LPCA has an ultralow density (42 mg·cm–3) and ultrahigh light absorbance (97.3%) without the need of additional expensive photothermal materials. Moreover, LPCA can regulate the intermediate water content and absorb energy from the environment. Based on these advantages, the evaporation rate of the LPCA evaporator can reach up to 2.40 kg·m–2·h–1 under 1 sun with an energy efficiency of 93.5%. Additionally, LPCAs with high strength (4.48 MPa under 90% strain), self-floating, good salt resistance, and applicability under harsh conditions facilitate practical application for producing clean water

Effect of regional vs general anesthesia on incidence of postoperative delirium in older patients undergoing hip fracture surgery : The RAGA randomized trial

Importance: In adults undergoing hip fracture surgery, regional anesthesia may reduce postoperative delirium, but there is uncertainty about its effectiveness. Objective: To investigate, in older adults undergoing surgical repair for hip fracture, the effects of regional anesthesia on the incidence of postoperative delirium compared with general anesthesia. Design, Setting, and Participants: A randomized, allocation-concealed, open-label, multicenter clinical trial of 950 patients, aged 65 years and older, with or without preexisting dementia, and a fragility hip fracture requiring surgical repair from 9 university teaching hospitals in Southeastern China. Participants were enrolled between October 2014 and September 2018; 30-day follow-up ended November 2018. Interventions: Patients were randomized to receive either regional anesthesia (spinal, epidural, or both techniques combined with no sedation; n = 476) or general anesthesia (intravenous, inhalational, or combined anesthetic agents; n = 474). Main Outcomes and Measures: Primary outcome was incidence of delirium during the first 7 postoperative days. Secondary outcomes analyzed in this article include delirium severity, duration, and subtype; postoperative pain score; length of hospitalization; 30-day all-cause mortality; and complications. Results: Among 950 randomized patients (mean age, 76.5 years; 247 [26.8%] male), 941 were evaluable for the primary outcome (6 canceled surgery and 3 withdrew consent). Postoperative delirium occurred in 29 (6.2%) in the regional anesthesia group vs 24 (5.1%) in the general anesthesia group (unadjusted risk difference [RD], 1.1%; 95% CI, –1.7% to 3.8%; P = .48; unadjusted relative risk [RR], 1.2 [95% CI, 0.7 to 2.0]; P = .57]). Mean severity score of delirium was 23.0 vs 24.1, respectively (unadjusted difference, –1.1; 95% CI, –4.6 to 3.1). A single delirium episode occurred in 16 (3.4%) vs 10 (2.1%) (unadjusted RD, 1.1%; 95% CI, –1.7% to 3.9%; RR, 1.6 [95% CI, 0.7 to 3.5]). Hypoactive subtype in 11 (37.9%) vs 5 (20.8%) (RD, 11.5; 95% CI, –11.0% to 35.7%; RR, 2.2 [95% CI, 0.8 to 6.3]). Median worst pain score was 0 (IQR, 0 to 20) vs 0 (IQR, 0 to 10) (difference 0; 95% CI, 0 to 0). Median length of hospitalization was 7 days (IQR, 5 to 10) vs 7 days (IQR, 6 to 10) (difference 0; 95% CI, 0 to 0). Death occurred in 8 (1.7%) vs 4 (0.9%) (unadjusted RD, –0.8%; 95% CI, –2.2% to 0.7%; RR, 2.0 [95% CI, 0.6 to 6.5]). Adverse events were reported in 106 episodes in the regional anesthesia group and 102 in the general anesthesia group; the most frequently reported adverse events were nausea and vomiting (47 [44.3%] vs 34 [33.3%]) and postoperative hypotension (13 [12.3%] vs 10 [9.8%]). Conclusions and Relevance: In patients aged 65 years and older undergoing hip fracture surgery, regional anesthesia without sedation did not significantly reduce the incidence of postoperative delirium compared with general anesthesia. Trial Registration: ClinicalTrials.gov Identifier: NCT0221338