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It is of great interest to synthesize boron carbide nanomaterials and explore their novel properties. We reported the synthesis of belt-like Si-doped boron carbide nanomaterials at a low temperature of 1500 [degrees]C with no catalyst. The structures and formation mechanism were investigated. Broad photoluminescence spectra between 400 and 500 nm were observed under 380 nm light excitation. The mechanism of the blue shift of the as-received samples in comparison with the reported boron carbide nanostructured materials is discussed. Key words: boron carbide, nanobelts, microstructure, XPS, photoluminescence. La synthese de nanomateriaux a base de carbure de bore et l'exploration de leurs nouvelles proprietes revetent un grand interet. Nous decrivons la synthese de nanomateriaux a base de carbure de bore dope par le silicium formant des nanoceintures a temperature basse (1500 [degrees]C), sans catalyseur. Nous avons etudie la structure et le mecanisme de formation de ces nanomateriaux. Lorsque nous les avons soumis a l'excitation par une lumiere d'une longueur d'onde de 380 nm, nous avons observe de larges bandes dans les spectres de photoluminescence entre 400 et 500 nm. Nous avons etudie le mecanisme de deplacement vers le bleu des echantillons obtenus tels quels en les comparant a des materiaux nanostructures a base de carbure de bore decrits dans la litterature. [Traduit par la Redaction] Mots-cles : carbure de bore, nanoceintures, microstructure, XPS, photoluminescence., Introduction Boron carbide, which is well accepted as a stoichiometric [B.sub.4]C phase with a wide range of solid solubilities for carbon (~8 at.% C to ~20 at.% C), exhibits unique [...]

Objective: The aim of this study is to evaluate the clinical efficacy of injectable cemented hollow pedicle screw (CICPS) in the treatment of osteoporotic lumbar degenerative diseases through a large sample long-term follow-up study. Additionally, we aim to explore the risk factors affecting interbody fusion. Methods: A total of 98 patients who underwent CICPS for transforaminal lumbar interbody fusion (TLIF) for osteoporotic lumbar degenerative disease from March 2011 to September 2017 were analyzed. X-ray and electronic computed tomography (CT) imaging data were collected during preoperative, postoperative, and follow-up periods. The data included changes in intervertebral space height (ΔH), screw failure, cement leakage (CL), and intervertebral fusion. The patients were divided into two groups based on their fusion status one year after surgery: satisfied group A and dissatisfied group B. Surgical data such as operation time, intraoperative bleeding volume and surgical complications were recorded, and visual analog scale (VAS) and Oswestry disability index (ODI) were used to evaluate the improvement of lumbar and leg pain. Results: The mean follow-up time was 101.29 months (ranging from 70 to 128 months). A total of 320 CICPS were used, with 26 screws (8.13%) leaking, 3 screws (0.94%) experiencing cement augmentation failure, and 1 screw (0.31%) becoming loose and breaking. The remaining screws were not loose or pulled out. Female gender, decreased bone density, and CL were identified as risk factors affecting interbody fusion (P < 0.05). Early realization of interbody fusion can effectively prevent the loss of intervertebral space height (P < 0.05) and maintain the surgical treatment effect. Both VAS and ODI scores showed significant improvement during the follow-up period (P < 0.05). Binary logistic regression analysis revealed that decreased bone density and cement leakage were risk factors for prolonged interbody fusion. Conclusions: The results of long-term follow-up indicate that PMMA enhanced CICPS has unique advantages in achieving good clinical efficacy in the treatment of osteoporosis lumbar degenerative diseases. Attention should be paid to identify female gender, severe osteoporosis, and CL as risk factors affecting interbody fusion. [ABSTRACT FROM AUTHOR]

Objective To Chinesize the Nursing Home Care-related Quality of Life Scale (NHC-QoL) and to test its reliability and validity. Methods According to the Brislin model, the NHC-QoL scale was translated into Chinese and cross-cultural debugging was carried out. Using convenience sampling method, 198 elderly people from 4 nursing institutions in Shiyan city were investigated by questionnaire from March to July 2023 to evaluate the reliability and validity of the scale. Results There were 14 items in the Chinese version of NHC-QoL. The content validity index of each item was 0.7-1.0, and the content validity index of the scale was 0.929. Exploratory factor analysis extracted 5 common factors, which could explain 67.914% of the total variation. After discussion within the research group, the common factors were reduced to 2 common factors namely environment and service (11 items) and social interaction (3 items). The total Cronbach's α coefficient of the scale was 0.758 and the test-retest reliability was 0.783. Conclusion The Chinese version of NHC-QoL scale has good reliability and validity and can be used to evaluate the quality of life of the elderly in nursing institutions. [ABSTRACT FROM AUTHOR]

Core–shell structured SiO2@C nanospheres with different sizes were fabricated using a method of "template synthesis – organic coating – carbonizing". After etching away the SiO2 cores, hollow carbon (void@C) nanospheres were obtained. The microwave absorption properties of the different structured nanospheres were compared, and the size effect of the nanospheres was further discussed. The SiO2@C/paraffin composites with a filling ratio of 30 wt% achieved a broad effective absorption (reflection loss ≤−10 dB) of 7.4 GHz at a thickness of 3.2 mm, covering the whole X and Ku bands, and the minimum reflection loss reaches −41.7 dB at 17.6 GHz at a thickness of 2.6 mm. The void@C/paraffin composites achieved an effective absorption broadband of 7.1 GHz and a minimum reflection loss of −21.9 dB at a thickness of 2.2 mm and a low filling ratio of 2 wt%, meeting the requirements for industrial lighting applications. Moreover, for both structures, the nanospheres with larger diameters exhibited stronger absorption performance. The excellent EMW absorption performances of the core–shell SiO2@C/paraffin and void@C/paraffin composites are mainly due to polarization loss and electrical conductivity loss, respectively, depending on the mobility of the electrons in the materials. [ABSTRACT FROM AUTHOR]