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This paper presents a decoupled modal reduction method for the steady-state vibration analysis of vibro-acoustic systems characterized by non-classical damping. The proposed approach initially reduces the order of the coupled governing equations of the vibro-acoustic system through the utilization of non-coupled modes, subsequently employing the complex mode superposition technique to address non-classical damping effects. By leveraging non-coupled modes, this method circumvents the need to solve for coupled modes as required in traditional modal reduction techniques, thereby diminishing both computational complexity and cost. Furthermore, the complex mode superposition method facilitates the decoupling of coupled governing equations with non-classical damping, enhancing computational efficiency. Numerical examples validate both the accuracy and effectiveness of this methodology. Given that modal decomposition is independent of frequency, an analysis of computational efficiency across various stages further substantiates that this method offers significant advantages in terms of efficiency for computational challenges encountered over a broad frequency range.

Background: AIDS-related NK/T-cell lymphoma is a rare subtype of AIDS-related lymphomas, characterized by a poor prognosis and lack of standardized treatment protocols. To date, there have been no reported cases of AIDS-associated NK/T-cell lymphoma in remission followed by treatment-related acute myeloid leukemia (t-AML), where both the lymphoma and AML achieved remission and long-term survival through chemotherapy alone. Case presentation: We report a case of a patient diagnosed with AIDS-related extra-nodal NK/T-cell lymphoma (ENKTCL). The patient achieved complete remission after receiving six cycles of chemotherapy, local radiotherapy, and combination antiretroviral therapy (cART). Throughout the follow-up period, the patient continued cART treatment, maintaining an HIV-RNA level below the lower limit of detection. However, 70 months later, the patient developed new symptoms and was subsequently diagnosed with acute myeloid leukemia (AML) M4 subtype. Following the completion of 10 cycles of chemotherapy and ongoing cART, the patient achieved complete remission of AML, with an overall survival time exceeding 103 months from the initial ENKTCL diagnosis. Conclusions: This case highlights the effectiveness of chemotherapy combined with cART in the treatment of AIDS-associated NK/T-cell lymphoma and secondary treatment-related leukemia. This approach may serve as a viable option for patients who are not candidates for bone marrow transplantation. Furthermore, this case underscores the importance of long-term follow-up in the management of AIDS-associated malignancies.

Abstract Background Biliary tract cancers have garnered significant attention due to their highly malignant nature. The relationship between abnormal lipid metabolism and tumor occurrence and development is a research hotspot. However, its correlation with biliary tract cancers is unclear. Methods We enrolled 78 patients with biliary tract cancers and obtained data on clinical characteristics, pathological findings, and preoperative blood lipid indices, including total cholesterol (TC), high‐density lipoprotein cholesterol (HDL‐C), low‐density lipoprotein cholesterol (LDL‐C), triglycerides (TG), and lipoprotein (a) [Lp(a)]. Receiver operating characteristic (ROC) curves were used to determine the optimal predictive cutoff values of lipid indicators among the participants. Independent risk factors were determined using Cox regression, and survival was predicted using the Kaplan–Meier method. Statistical analyses were performed using SPSS software. Results Univariate Cox regression analysis revealed that the body mass index (BMI), tumor location, surgical margin, N stage, and abnormally increased LDL‐C, TG, and Lp(a) levels were significantly associated with poor prognosis of biliary tract cancers (p

Industrial water saving is an objective requirement for the high-quality development of the Yellow River Basin, as water resource is the largest rigid constraint. In this study, water resources input-output model, structural decomposition analysis (SDA) and structural path analysis (SPA) were constructed to decompose the driving factors of total water use in typical water-deficient provinces (Ningxia, Shanxi, and Henan) in China's Yellow River Basin, to calculate their water use at each production stage and identify their key water-saving pathways. The results were as follows: (i) Water intensity had the most obvious impact on total water saving, resulting in efficiency improvements of 81.39%, 9.21%, and 78.45% for each province, respectively. The next factor was the final demand structure, which suppressed total water-saving efforts by 24.23%, 11.52%, and 113.12% in the respective provinces. (ii) The key water-saving paths in the typical water-deficient provinces of the Yellow River Basin were primarily centered around Sector 1. (iii) Water intensity had a strong water-saving effect on the key paths in the three provinces, with contribution rates of 100.42%, 59.02%, and 42.34% for Ningxia, Henan, and Shanxi, respectively. Final demand also contributed to water-saving in the key paths of Shanxi and Henan, with contribution rates of 35.06% and 28.23%, respectively. However, it inhibited water-saving efforts in the key paths of Ningxia, reducing it by 8.64%. Policy measures should be tailored to local conditions.

This paper reports the detection of ferric ions (Fe ^3+ ) based on nitrogen and sulfur co-doped carbon quantum dots. These nitrogen and sulfur co-doped carbon quantum dots were synthesized via a hydrothermal route using northern Shaanxi potatoes as carbon sources and ammonium sulfate as nitrogen and sulfur sources. The quantum yields of the carbon quantum dots were found to be 16.96% and 4.23% with and without doping, respectively. The structural details, morphology, and optical properties of carbon quantum dots were analyzed using Fourier transform infrared spectroscopy (FT-IR), x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), ultraviolet-visible absorption spectroscopy (UV–vis), and fluorescence spectroscopy. The as-prepared co-doped carbon quantum dots were utilized as a fluorescent probe for detecting Fe ^3+ ions, where the fluorescence intensity of carbon quantum dots was remarkably quenched in the presence of Fe ^3+ ions. A good linear relationship for Fe ^3+ ion detection was obtained from 0 to 500 μ mol/L with a detection limit as low as 0.26 μ mol/L. Furthermore, the proposed method also provided satisfactory results in the tap water.

A disordered Nd:SrLaGaO4 (Nd:SLG) laser crystal was successfully grown via the Czochralski (CZ) technique. The crystal structure, refractive index, polarized absorption spectra, and stimulated emission spectra were measured. The spectroscopic properties were studied intensively with the Judd–Ofelt (J-O) theory. The maximum absorption cross sections of π- and σ-polarization at 806 nm were calculated to be 3.73 × 10−20 and 4.05 × 10−20 cm2, corresponding to FWHMs of 6.00 and 6.10 nm, respectively. The maximum emission cross sections of π- and σ-polarization at 1076 nm were 3.97 × 10−20 and 4.12 × 10−20 cm2, with FWHMs of 30.21 and 19.44 nm, respectively. The decay life of the Nd3+:4F3/2 energy level was fitted to be 0.152 ms, and the fluorescence quantum efficiency was 72.72%. The inhomogeneous broadening in spectra benefiting from the disordered structure indicates the Nd:SLG crystal is a promising gain medium for ultrafast laser and tunable laser generations in the near infrared region.