ObjectiveAccurate preoperative identification of cervical lymph node metastasis (CLNM) is essential for clinical management and established of different surgical protocol for patients with papillary thyroid microcarcinoma (PTMC). Herein, we aimed to develop an ultrasound (US) features and clinical characteristics-based nomogram for preoperative diagnosis of CLNM for PTMC.MethodOur study included 552 patients who were pathologically diagnosed with PTMC between January 2015 and June 2019. All patients underwent total thyroidectomy or lobectomy and divided into two groups: CLNM and non-CLNM. Univariate and multivariate analysis were performed to examine risk factors associated with CLNM. A nomogram comprising the prognostic model to predict the CLNM was established, and internal validation in the cohort was performed.ResultsCLNM and non-CLNM were observed in 216(39.1%) and 336(60.9%) cases, respectively. Seven variables of clinical and US features as potential predictors including male sex (odd ratio [OR] = 1.974, 95% confidence interval [CI], 1.243-2.774; P =0.004), age < 45 years (OR = 4.621, 95% CI, 2.160-9.347; P < 0.001), US-reported CLN status (OR = 1.894, 95% CI, 0.754-3.347; P =0.005), multifocality (OR = 1.793, 95% CI, 0.774-2.649; P =0.007), tumor size ≥ 0.6cm (OR = 1.731, 95% CI,0.793-3.852; P =0.018), ETE (OR = 3.772, 95% CI, 1.752-8.441;P< 0.001) and microcalcification (OR = 2.316, 95% CI, 1.099-4.964; P < 0.001) were taken into account. The predictive nomogram was established by involving all the factors above used for preoperative prediction of CLNM in patients with PTCM. The nomogram model showed an AUC of 0.839 and an accuracy of 77.9% in predicting CLNM. Furthermore, the calibration curve demonstrated a strong consistency between nomogram and clinical findings in prediction CLNM for PTMC.ConclusionsThe nomogram achieved promising results for predicting preoperative CLNM in PTMC by combining clinical and US risk factor. Our proposed prediction model is able to help determine an individual’s risk of CLNM in PTMC, thus facilitate reasonable therapy decision making.

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A series of in situ dodecyl trimethyl ammonium bromide (DTAB)-modified small-crystal Y zeolites have been successfully synthesized by DTAB addition to the seed synthesis procedure, which was used to create the small crystal size Y zeolites. Compared to the Y zeolites prepared without DTAB, the Y zeolites prepared with DTAB have a uniform morphology and mesoporous structure, a larger specific surface area (up to 32.3 m 2 g −1 increase), a smaller crystal size (up to 66 nm reduction), and more Bronsted acid sites (up to 55 μmol/g increase). After loading with NiW, the corresponding NiW catalysts were utilized in the hydrocracking of n-hexadecane. It is evident from the catalytic performance that the catalysts containing DTAB-modified smallcrystal zeolites have a higher yield and selectivity of primary cracking products compared with the Y zeolites without DTAB modification. Moreover, the conversion of n-hexadecane is also higher due to its low mass-transfer resistance, high dispersion, and sulfation of W species. When the molar ratio of DTAB/Al 2 O 3 is 0.15, the corresponding catalyst has the optimum balance between cracking and hydro−dehydrogenation activity. Therefore, it has the most excellent catalytic performance and a 7.3% increase in C 8 −C 12 yield.

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A novel SAPO-11 molecular sieve with a lamellar structure and flower-like morphology was synthesized using cationic surfactant cetyltrimethylammonium bromide (CTAB) as the surfactant and KF as the mineralizer. Meanwhile, the effect of various CTAB additions on the structure and properties of SAPO-11 molecular sieves was also investigated. A number of characterization analyses’ findings reveal that, compared with conventional spherical SAPO-11 molecular sieves, flower-like SAPO-11 molecular sieves have the following advantages: (1) Flower-like SAPO-11 molecular sieves have open pores and larger mesopores, with suitable distribution of mesopores. (2) The prepared flower-like SAPO-11 molecular sieves have a lower total acid value but have a higher proportion of Brønsted acid sites, with suitable acidity. (3) The flower-like NiW/SAPO-11 catalysts have better dispersion of WS2 slabs and higher balance and proximity between metal sites and acid sites. The synthesized flower-like NiW/SAPO-11 showed significant isomerization performance and low cracking selectivity during the isomerization of n-hexadecane. When the conversion rate of n-hexadecane reached 77.0%, the yield of i-hexadecane was 59.4%.