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In this study, the two eco-friendly flame retardants of the polymeric type (PA-PEI) and monomeric type (PA-Arg) phytate amine complexes were prepared via the ionic reaction of polyethylenimine (PEI) or arginine (Arg), respectively, with phytic acid in an aqueous solution. The chemical structure and thermal stability of PA-PEI and PA-Arg were characterized by Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). In order to improve the flame retardancy of the polylactic acid (PLA)/polybutylene succinate (PBS) biocomposites (P/15B-based biocomposites), the flame retardants PA-PEI and PA-Arg were embedded into P/15B by thermal blending procedures, respectively, to obtain P/15B/PA-PEI series and P/15B/PA-Arg series biocomposites. The TGA analyses demonstrated that incorporating PA-PEI or PA-Arg into the P/15B polymer enhances the char residues in these P/15B biocomposites. The XRD and SEM analyses of the P/15B/PA-PEI series and P/15B/PA-Arg series suggested the PA-PEI and PA-Arg were embedded into the P/15B polymer matrixes, respectively. The mechanical results showed that P/15B/PA-Arg series exhibited higher values than the P/15B/PA-PEI series biocomposite, which were associated with less roughness of P/15B/PA-Arg than that of the P/15B/PA-PEI series. The flammability results of the P/15B/PA-PEI series and P/15B/PA-Arg series biocomposites exhibited a V-2 level in UL94 vertical test. Further, the fire resistance performance of P/15B-based biocomposites was enhanced by incorporating PA-PEI or PA-Arg into the P/15B matrix through the analyses of the Cone calorimeter test (CCT), as a comparison with neat P/15B. The peak heat release rate (pHRR), the total heat release rate (THR), and char residues of P/15B/15PA-Arg biocomposite were significantly improved to 280.26 kW/m2, 107.89 MJ/m2, and 10.4%, respectively. The enhancement of the P/15B-based composites’ fire resistance is attributed to the interplay effect on the catalytic and condensed effect on the thermal decomposition of PA-PEI or PA-Arg in P/15B biocomposites. The resultant eco-friendly flame-retardant P/15B biocomposites reported in this study can be widely applied in various fields, including construction, electronic appliances, and other fields.

The higher acidity in fruits compared with grapes was one of the main obstacles to producing high-quality fruit wines. In the present research, the effect of the split batch fermentation pattern on the metabolites of greengage wines was investigated. This fermentation pattern included whole fruit immersion in the sucrose and coculturing Saccharomyces bayanus Y4 with Torulaspora delbrueckii Y7. These results showed that the contents of total acidity and dominant organic acids were significantly reduced among the batches. Aliphatic compounds were decreased with the batches, while aromatic compounds that contributed to flavor improvement were increased oppositely. The acetate esters, ketones, and terpenes contents were significantly increased in the first batch of coculture. In addition, acidic stress largely affected the kinetics characteristics of greengage wine on a pilot scale. Interestingly, the increment of total acidity was closely associated with the rate of total sugar consumption, which was affected by microbial activities. The acidity content was significantly declined and distinct flavour profiles were formed in split batch and coculture fermentation of greengage wines. It provides a new avenue to enhance the flavor and quality of fruit wines.

Objectives The residential population of an area is an incomplete measure of the number of people that are momentarily present in the area, and of limited value as an indicator of exposure to the risk of crime. By accounting for the mobility of the population, measures of ambient population better reflect the momentary presence of people. They have therefore become an alternative indicator of exposure to the risk of crime. This study considers the heterogeneity of the ambient population by distinguishing residents, employees and visitors as different categories, and explores their differential impact on thefts, both on weekdays and weekends. Methods We analyze one-year of police recorded thefts across 2104 1 km2 grid cells in a central area in Beijing, China. Controlling for the effects of attractiveness, accessibility, and guardianship, we estimate a series of negative binominal models to investigate the differential effects of the three groups (residents, employees and visitors) in the ambient population on crime frequencies, both on weekdays and during weekends and holidays. Results Overall, larger ambient populations imply larger theft frequencies. The effect of visitors is stronger than the effects of residents and employees. The effects of residents and employees vary over the course of the week. On weekdays, the presence of residents is more important, while the reverse holds true during weekends and holidays. Discussion The effects of ambient population on thefts vary by its composition in terms of social roles. The larger role of visitors is presumably because in addition to being potential victims, residents and employees may also exercise informal social control. In addition, they spend more time indoors than where risk of theft is lower, while visitors might spend more time outdoors and may also bring about greater anonymity and weaken informal social control.

PurposeTo explore the difference in the effectiveness of gallium-68 fibroblast activation protein inhibitor (68Ga-FAPI-04) PET/CT and fluorine-18 fluorodeoxyglucose (18F-FDG) PET/CT for the initial staging of patients with nasopharyngeal carcinoma (NPC).MethodsThe Affiliated Hospital of Southwest Medical University hosted this single-center prospective investigation (Clinical Trials registration No.ChiCTR2100044131) between March 2020 and September 2021. Within a week, all subjects underwent MR scans, 68Ga-FAPI-04 PET/CT, and 18F-FDG PET/CT in order. The effectiveness of medical staging employing 68Ga-FAPI-04 and 18F-FDG PET/CT was compared.ResultsTwenty-eight patients with primary NPC were evaluated (mean age53 ± 11 years). 68Ga-FAPI-04 PET/CT indicated an elevated recognition rate for diagnosing primary tumors (28/28 [100%] vs. 27/28 [96%]) and lymph node metastases (263/285 [92%] vs. 228/285 [80%]), but a lower detection rate for distant metastases (5/7 [71%] vs. 7/7 [100%]) compared with 18F-FDG PET/CT. A significant association between the maximum standard uptake value (SUVmax) of 18F-FDG PET and 68Ga-FAPI-04 PET was found in the primary cancers (r = 0.691, p < 0.001). In comparison to 18F-FDG PET/CT, 68Ga-FAPI-04 PET/CT upstaged the T stage in five patients while downstaging the N stage in seven patients. 68Ga-FAPI-04 PET/CT corrected the overall staging of five patients on18F-FDG PET/CT.Conclusion68Ga-FAPI-04 PET/CT is preferable to 18F-FDG PET/CT for NPC staging in terms of the detection efficiency for primary tumors and lymph node metastasis. This is especially true when evaluating the primary cancer and any spread to contiguous tissues. It is possible to improve the staging assessment of NPC by using 68Ga-FAPI-04 PET/CT in conjunction with 18F-FDG PET/CT.

Amine-functionalized covalent organic frameworks (COFs) hold great potential in diversified applications. However, the synthesis is dominated by postsynthetic modification, while the de novo synthesis allowing for direct installation of amine groups remains a formidable challenge. Herein, we develop a site-selective synthetic strategy for the facile preparation of amine-functionalized hydrazone-linked COF for the first time. A new monomer 2-aminoterephthalohydrazide (NH

Iridium-based perovskites show promising catalytic activity for oxygen evolution reaction (OER) in acid media, but the iridium mass activity remains low and the active-layer structures have not been identified. Here, we report highly active 1 nm IrOx particles anchored on 9R-BaIrO3 (IrOx/9R-BaIrO3) that are directly synthesized by solution calcination followed by strong acid treatment for the first time. The developed IrOx/9R-BaIrO3 catalyst delivers a high iridium mass activity (168 A gIr-1), about 16 times higher than that of the benchmark acidic OER electrocatalyst IrO2 (10 A gIr-1), and only requires a low overpotential of 230 mV to reach a catalytic current density of 10 mA cm-2geo. Careful scanning transmission electron microscopy, synchrotron radiation-based X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy analyses reveal that, during the electrocatalytic process, the initial 1 nm IrOx nanoparticles/9R-BaIrO3 evolve into amorphous Ir4+OxHy/IrO6 octahedrons and then to amorphous Ir5+Ox/IrO6 octahedrons on the surface. Such high relative content of amorphous Ir5+Ox species derived from trimers of face-sharing IrO6 octahedrons in 9R-BaIrO3 and the enhanced metallic conductivity of the Ir5+Ox/9R-BaIrO3 catalyst are responsible for the excellent acidic OER activity. Our results provide new insights into the surface active-layer structure evolution in perovskite electrocatalysts and demonstrate new approaches for engineering highly active acidic OER nanocatalysts.

In this work, a method combining the spray-drying process and rolling ball method was first selected to mass fabricate Li2TiO3 tritium breeder ceramic pebbles. Herein, we overcome the issues namely complex production, high manufacturing cost, and lower mechanical strength in previous reports. The Li2TiO3 powder with high packing density after the spray drying process will self-agglomerate to form denser structured pebbles during the rolling ball process assisted by sesbania gum binder solution. The stability of slurry, different binder, binder concentrations, the formation mechanism, and the morphology of green pebbles were investigated by using viscometer, SEM. Moreover, the force on the Li2TiO3 green pebbles was also analyzed during the rolling ball process. After the debinding and densification process, the Li2TiO3 pebbles have a uniform diameter of 1.2 mm and good sphericity of 0.97. The Micro-CT instrument showed that the internal structure of the Li2TiO3 pebbles was dense. The experiment's confirmation shows that the Li2TiO3 ceramic pebbles sintered at 1000 °C have optimal mechanical properties such as a crushing load of 108 N and relative density of 92.4%TD, which is much larger than that of the pebbles obtained using traditional methods. This work not only overcomes the core-shell structure but also provides a new platform for better mechanical properties for studying the other materials systems in the future.

This study aimed to investigate the effect of repeated batch fermentation of cocultured Saccharomyces bayanus Y4 and Torulaspora delbrueckii Y7 on the quality of greengage wine. The acidity, as well as citric acid and L-malic acid content, decreased significantly with the batches. The citric acid content of the single culture in each batch was 58.59, 26.27, and 8.45 g/L, respectively. Additionally, the ester content increased with the batches. The respective values were 1627.93, 2249.46, and 2491.17 μg/L for the prophase of coculture. However, volatile content in the fresh wine of Y4 yeast in each batch was high. Ketone and terpene contents in the first batch of coculture significantly increased from 31.64 to 95.60 μg/L and 58.58–95.13 μg/L, respectively. Furthermore, a significant difference was observed between the microbial communities fermented using single culture and coculture. The change in fungal community diversity for coculture pattern was higher than that in the mash-inoculated single strain, which decreased the abundance of dominant fungi. Pichia, Stropharia, Suillus, Malassezia, Trichoderma, Faecalibacterium, and Butyricicoccus were associated with esters, terpenes, phenylethyl alcohol, and β-ionone. Our study provides a new avenue to improve the flavour and quality of wine brewed using a characteristic fruit.

The development of two-dimensional (2D) magnetic semiconductors remains a challenging issue in materials science, and plays an important role in the next-generation spintronics devices. Herein, we demonstrate that a 2D semiconducting antiferromagnetic Cu-MOF can be endowed with intrinsic room-temperature ferromagnetic coupling using a ligand cleavage strategy to regulate the inner magnetic interaction within the Cu dimers. Notably, employing the element-selective X-ray magnetic circular dichroism (XMCD) technique, we provide an unambiguous evidence for intrinsic ferromagnetism. Exhaustive structural characterizations confirm that the change of magnetic coupling is caused by the increased distance between Cu atoms within a Cu dimer. Theoretical calculations reveal that the ferromagnetic coupling is enhanced with the increased Cu-Cu distance, which depresses the hybridization between 3d orbitals of nearest Cu atoms. Our work provides an effective avenue to design and fabricate MOF-based semiconducting room-temperature ferromagnetic materials, and promotes their practical applications in next-generation spintronics devices.

PurposeThe present study was performed to detect the prevalence of myopia among primary-school students in Xi'an, north-western of China.MethodsThe present study was a school-based study with students aged from 6 to 13 years old. All the individuals underwent ophthalmological examination and spherical equivalent (SE) of refractive error were measured with non-cycloplegic refraction. Myopia was defined as a SE of ≤ -0.5 diopters (D), and further divided into three stratified groups based on SE: low myopia (≤ -0.5 to >-3.0 D), moderate myopia (≤ -3.0 to >-6.0 D), and high myopia (≤ -6.0 D). Relative risk factors, including age, sex, grade and ethnicity were investigated using questionnaire.ResultsA total of 4,680 individuals were eligible for this survey and 4,654 (99.4% participation rate) were finally included (51.2% boys). The mean age of participants was 8.756 ± 1.727 years. The whole city-level prevalence of total myopia was 57.1% (95% CI: 55.7–58.6%). Additionally, the prevalence of low, moderate, and high myopia was 45.0% (95% CI: 43.5–46.4%), 11.1% (95% CI: 10.2–12.0%), and 1.0% (95% CI: 0.7–1.3%), respectively. Moreover, grade (education level) instead of age, sex and ethnicity was the most essential risk factor for prevalence of overall myopia (OR = 1.844, 95% CI: 1.605–2.119), and an increase of prevalence by 84.4% per grade was seen. Furthermore, similar associations of grade were significant with low myopia (OR = 1.613, 95% CI: 1.385–1.877) and moderate myopia (OR = 2.186, 95% CI: 1.693–2.823), meanwhile, prevalence of low myopia and moderate myopia demonstrated an increase of prevalence by 61.3 and 118.6% per grade, respectively. None of the factors included in the present study was significant risk factor for high myopia.ConclusionsThe present study investigated a non-negligible high prevalence of myopia among primary-school students in Xi'an, north-western of China, and a gradual increasing in proportion with education level.

To explore the difference in the effectiveness of gallium-68 fibroblast activation protein inhibitor (The Affiliated Hospital of Southwest Medical University hosted this single-center prospective investigation (Clinical Trials registration No.ChiCTR2100044131) between March 2020 and September 2021. Within a week, all subjects underwent MR scans,Twenty-eight patients with primary NPC were evaluated (mean age53 ± 11 years).

Infusing undergraduate curricula with authentic research training is an important contemporary challenge. Such exposure typically occurs through mentored research (MR) or course-based undergraduate research experiences (CUREs). In Asian contexts, CURE implementation is rare, while MR is often a graduation requirement. In this study, mentor interviews and mentee focus groups were used to characterize the learning challenges associated with this requirement at a Chinese university. An intensive 6-week CURE was then implemented as an MR preparatory program to help mitigate the identified challenges. This program contained seven site-specific features not typically included in other CUREs, each designed to improve different aspects of student readiness for MR. Post-CURE surveys, focus groups, and interviews demonstrated CURE enrollment significantly improved subsequent MR outcomes. Almost 90% of all enrollees, for example, began their first MR experience in their second year, more than twice the rate of non-enrollees. Enrollees also reported greater confidence in their research skills and more frequent experiences working in multiple labs. This study reports both immediate CURE and downstream MR outcomes, using the former to help explain the latter. A comprehensive CURE implementation process is described, offering a potential model for the design of other programs with similar research enhancement goals.