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PURPOSE: To evaluate a computer-aided diagnosis (CAD) technique in predicting malignancy for cytologically indeterminate thyroid nodules (TNs) as compared with different experienced radiologists. METHOD: 436 patients with 436 cytologically indeterminate TNs on fine-needle aspiration cytology (FNAC) were included and all were confirmed by surgical pathology. They were retrospectively analyzed with respect to ultrasound (US) characteristics using a commercially available CAD system (AmCAD-UT; AmCad BioMed, Taiwan, China) and reviewed by one junior and one senior radiologists.The CAD system and different experienced radiologists stratified the risk of malignancy using ACR TI-RADS category. The diagnostic performance by different experienced radiologists independently and after consulting the CAD (different experienced radiologists + CAD) and by the CAD alone were compared. RESULTS: The different experienced radiologists showed significantly higher specificities than the CAD system alone. The combination of radiologist and CAD system showed improved diagnostic performance with an AUC (Area under the curve) of 0.740 in the senior radiologist and 0.677 in the junior radiologist, as compared with CAD (AUC: 0.585) alone (all P

At present, fiber reinforce plastic (FRP) sucker rod has the advantages of high tensile strength, light weight and strong corrosion resistance which gradually applied and popularized in offshore oil and gas field. However, the bonded joint of FRP sucker rod is particularly prone to break and fall off. Current research works mainly focus on the mechanical properties of FRP sucker rod and less consideration was given to adhesive performance. This paper proposed a finite element model (FEM) of bonded joint. The maximum predicted load of bonded joint was acquired and the axial distribution of adhesion stress and slip distance in the bonding interface was studied, which can provide theoretical basic of bonded joint and extend the service life of downhole pumping operation.

Background: The risk stratification system of the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) for thyroid nodules is affected by low diagnostic specificity...

Background: To evaluate the diagnostic performance of a novel two-dimensional quantitative shear wave elastography (SWE) of virtual touch tissue imaging quantification (VTIQ) in the differential diagnosis between benign and malignant thyroid nodules.Methods: Two hundred and six solid thyroid nodules were included in this prospective study. Conventional ultrasound and VTIQ examinations were performed. The diagnostic performances of US, VTIQ, and the combination of the two methods were compared. The usefulness of VTIQ in different size of nodules was also assessed.Results: There were 113 benign nodules and 93 malignant nodules on fine needle aspiration (FNA) or histology. The shear wave velocities (SWVs) in malignant nodules were all significantly higher than those in benign nodules (SWV max: 4.01 ± 1.72 m/s vs 3.25 ± 1.01 m/s, SWV min: 2.87 ± 0.69 m/s vs 2.46 ± 0.67 m/s, SWV mean: 3.33 ± 0.89 m/s vs 2.85 ± 0.81 m/s, SWV median: 3.31 ± 0.88 m/s vs 2.82 ± 0.77 m/s, all P value < 0.001). After combined VTIQ with ultrasound, the diagnostic performances improved compared with ultrasound alone or VTIQ alone. As for lesions of different sizes, areas under curve (AUC) for the largest diameter of nodules ≤ 1.0 cm was 0.711, which was lower than that for the largest diameter of the nodules > 1.0 cm (AUC was 0.862) (P < 0.05). Conventional ultrasound features such as halo sign and microcalcification were predictors for lymphatic metastasis in malignant thyroid nodules (P < 0.05).Conclusions: VTIQ is a new method for measuring stiffness of thyroid lesions qualitatively. The diagnostic performance of combined using VTIQ and conventional ultrasound was better than that of using either alone. Malignant thyroid nodules with conventional ultrasound features such as halo sign and microcalcification were more likely to have lymphatic metastasis. The evaluation of small thyroid lesions remained a difficult problem.

The purpose of this multicenter study was to compare the differential diagnostic value of the 2015 American Thyroid Association (ATA) and 2017 American College of Radiology (ACR) practice guidelines and elastography in thyroid nodules. This study also investigated whether the diagnostic value of practice guidelines can be improved, and the unnecessary biopsy rate decreased in combination with elastography. A total of 498 thyroid nodules were evaluated using the ATA and the ACR guidelines. Strain elastography, acoustic radiation force impulse imaging and point-shear wave elastography were used to assess the nodules. The suspicious levels were downgraded or upgraded after combination and unnecessary biopsy rates were calculated, respectively. The diagnostic performance of the practice guidelines was better than that of elastography. The ACR guidelines had a lower unnecessary biopsy rate and similar diagnostic performance compared with the ATA guidelines. The unnecessary biopsy rates significantly decreased when the ACR guidelines were combined with elastography, but the rates did not decrease when the ATA guidelines were combined with elastography.

To investigate the value of ultrasound (US) and clinicopathological features of papillary thyroid cancer (PTC) in predicting Telomerase Reverse Transcriptase (TERT) promoter mutations. Preoperative US images of 351 surgically confirmed PTCs were evaluated in terms of PTCs size and US features. The basic clinicopathological features were also retrieved. Univariate and multivariate analyses were performed to identify the risk factors for TERT promoter mutations. A scoring system was developed based on the cumulative number of risk factors. The area under the receiver operating characteristic curve (AUC) and cut-off value were calculated to evaluate the diagnostic performance of the scoring system for predicting TERT promoter mutations. TERT promoter mutations were found in 4.84% (17/351) of patients with PTCs. Patient age >50 years (OR: 6.244, P = 0.006), multifocality (OR: 21.071, P = 0.022), taller-than-wide shape (OR: 4.934, P = 0.029), microlobulated margin (OR: 4786, P = 0.032), and capsule contact or involvement (OR: 4.668, P = 0.030) were independent risk factors for TERT promoter mutations. TERT promoter mutations were relevant to more suspicious US and clinicopathological features than TERT promoter wild-type PTC (median, 4 vs. 1, P

Objectives: To explore whether prostate-specific antigen (PSA) affects the choice of prostate puncture methods by comparing MRI-ultrasound fusion targeted biopsy (MRI-TBx) with transrectal ultrasound systematic biopsy (TRUS-SBx) in the detection of prostate cancer (PCa), clinically significant prostate cancer (csPCa) and non-clinically significant prostate cancer (nsPCa) in different PSA groups (20.0 ng ml−1). Methods: A total of 190 patients with 215 lesions who underwent both MRI-TBx and TRUS-SBx were included in this retrospective study. PSA was measured pre-operatively and stratified to three levels. The detection rates of PCa, csPCa and nsPCa through different methods (MRI-TBx, TRUS-SBx, or MRI-TBx +TRUS SBx) were compared with stratification by PSA. Results: Among the 190 patients, the histopathological results revealed PCa in 126 cases, including 119 csPCa. In PSA −1 group, although the detection rates of PCa and csPCa by MRI-TBx were higher than those of TRUS-SBx, no significant differences were observed (p = 0.741; p = 0.400). In PSA 10.0–20.0 ng ml−1 group, difference between the detection rate of csPCa with TRUS-SBx and the combined method was statistically significant (p = 0.044). As for PSA >20.0 ng ml−1, MRI-TBx had a higher csPCa rate than TRUS-SBx with no statistical significance noted (p = 0.600). Conclusion: MRI-TBx combined with TRUS-SBx could be suitable as a standard detection approach for csPCa in patients with PSA 10.0–20.0 ng ml−1. As for PSA >20.0 and −1, both MRI-TBx and TRUS-SBx might provide effective solutions for tumor detection. Advances in knowledge: This study gives an account of choosing appropriate prostate puncture methods through PSA level.

Objectives: Ultrasound-guided fine-needle aspiration (FNA) is the most accurate and economical means for the differential diagnosis of thyroid nodules, but false negative results also existed. This study aimed to predict the false negative results of FNA, reduce the missed diagnosis and improve the current management strategy of thyroid nodules. Methods: A total of 1232 consecutive patients with thyroid nodules who received FNA and BRAF V600E detection were adopted. All patients received both CUS (conventional ultrasound) and SWE (shear wave elastography) examinations and characteristics of these thyroid nodules were analyzed to evaluated the diagnostic performances of risk factors for malignancy.Results: Finally, 26 nodules with benign cytology and BRAF V600E mutations were enrolled. Undefined boundary, microcalcification and E max ratio > 1.49 were risk factors for malignancy (P 1.49 respectively. There was no difference between benign and malignant nodules in the patient age, sex and nodule sizes (P>0.05).Conclusions: Undefined boundary, microcalcification and E max ratio > 1.49 were risk factors for malignancy in benign cytology nodules. When FNA results were benign but above characteristics could be found in the thyroid nodules with BRAF V600E mutation, further clinical decisions should be carried out to reduce the missed diagnosis.

The purpose of the study was to explore the differences of conventional ultrasound characteristics, thyroid imaging reporting and data system (TI-RADS) category and shear wave speed (SWS) measurement between follicular adenoma (FA) and follicular thyroid carcinoma (FTC). Twenty-eight FTCs and 67 FAs proven by surgery were retrospectively included for analysis. Conventional ultrasound and point-shear wave elastography (p-SWE) were performed in all of the included patients. The ultrasound features, American Thyroid Association (ATA) TI-RADS category and American College of Radiology (ACR) TI-RADS category, SWS measurement were compared between the two groups. Receiver operating characteristic (ROC) curve was performed and area under ROC curve (AUC) was obtained for significant features. There were no statistical differences in mean age (46.9±15.7years vs. 48.6±13.6years, P = 0.639), gender (9 males, 32.1% vs. 18 males, 29.0%, P = 0.766) and mean diameter (28.3±16.2 mm vs. 33.8±11.9 mm, P = 0.077) between FTCs and FAs. Hypoechogenicity, lobulated or irregular margin, macrocalcification were more common in FTCs than FAs (all P

The development of rapid and simple approaches for detection of G-quadruplex DNA structures has attracted significant attention to disclose their diverse physiological and pathological functions. Thiazole orange (TO) is a common fluorescence probe used for the detection of G-quadruplexes. However, it still suffers from some common problems like non-selective for G-quadruplex and emission in the lower wavelength region of spectrum, thus hampering its further applications. Probes with turn-on fluorescence in the far-red region are highly sought-after due to minimal auto-fluorescence and cellular damage. In this paper, we described a far-red fluorescent probe (L-1) by introducing an amine group into styrylquinolinium scaffold. The experimental results indicated that L-1 exhibited significant fluorescence enhancement when treated with G-quadruplexes but retained weak fluorescence in the presence of duplex DNAs. In addition, this probe also displayed higher binding affinity for parallel G-quadruplexes. The characteristics of L-1 were further investigated with UV–vis spectrophotometry, fluorescence, circular dichroism, KI quenching, FID assay and molecular docking to validate optical photophysical properties, as well as the selectivity, sensitivity and detailed binding mode toward G-quadruplex DNAs.

PsdVoigt2 function was used to fit SGW function and a series of bar beam elements based on the theory of SGW and wavelet finite element were constructed. Traditional finite element polynomial interpolation was replaced by the SGW scaling function and transformation matrix was utilized to transform wavelet interpolation coefficients to physical space. Thereby the shape function and element were constructed. The precision of a series of bar beam elements constructed with the SGW scale function as the interpolation function were verified by the calculation cases. The calculation results showed that the precision of the SGW-based element constructed was higher in calculating the deformation and strain. And the SGW-based bar beam element constructed enriched the element library of wavelet-finite element method.

Under the conditions of downhole closure in oil well, the wired transmission of the data signal including downhole temperature and pressure cannot be achieved. To solve this problem, an experimental study of short distance wireless system for downhole data transmission was launched. This technology is based on the means of electromagnetic coupling to achieve the wireless transmission of signals by leaps and bounds. Through the test bench of the wireless electromagnetic short pass system, we carry out the frequency characteristics of the transmission channel experiments, and provide the foundation for the design of downhole power supply lines and the selection of the electronic components. The tests show that the output characteristics of the downhole wireless signal transmission system are stable. They did not change with the excitation voltage, and the transmission frequency band between 50-100 KHz is better.

An MG-2000 high-speed and high-temperature friction-abrasion testing machine was used to evaluate the friction and wear behaviors of AISI1045 steel sucker rod sliding against J55 tubing string and J55 tubing strings coated with spray-welded wear-resistant coatings of various thicknesses in a ring-on-ring configuration and under the lubrication of oilfield wastewater as the lubricating medium. The worn surface morphologies of the sucker rod specimens coupled with the J55 tubing string and the J55 tubing string coated with the wear-resistant coating were observed with a scanning electron microscope. As the results, it was effective to increase the wear-resistance of the frictional pair with the addition of the wear-resistant coatings on the tubing string surface. The wear-resistant coating of a proper thickness also contributed to reducing the friction coefficient to some extent, which was helpful to reduce the friction force between the sucker rod and tubing string pair and increase the service lifetime of the pair. The decreased wear rates of the sucking rod specimens coupled with the tubing string specimens coated with the wear-resistant coating of a proper thickness were attributed to the action of the coating in decreasing adhesion wear. Moreover, the tubing string specimen recorded little difference in wear rate at normal temperature and 60°C. However, the sucker rod specimen registered as lightly larger wear rate at 60°C than at room temperature, which could be attributed to the enhanced adhesion wear and mild corrosive wear at elevated temperature. It was imperative to properly control the thickness of the wear-resistant coating on the tubing string surface so as to bring its friction-reducing and antiwear action into effect.

To evaluate the therapeutic effect of a short course chemotherapy on initially sputum positive cavitary pulmonary tuberculosis or tuberculoma by bacteriological examination of specimens through percutaneous lung biopsy after the chemotherapy.Eighty-three cases of initially sputum positive pulmonary tuberculosis with cavities or tuberculoma were included from Jan. 2002 and May. 2004. The patients finished a course of chemotherapy (2HREZ/4HR), and the sputum was converted to smear-negative and culture-negative, but cavities or tuberculoma remained on the chest X-ray. Lung specimens were obtained from the wall or content of the cavity or from the tuberculoma by CT-guided percutaneous lung biopsy for bacteriological examination within one month after the course.All the needle biopsy specimens were smeared and cultured for Mycobacterium tuberculosis. Eight cases (8/83, 9.6%) showed positive results: 3 were smear-positive and culture-positive, and 5 smear-negative but culture-positive. Drug susceptibility test showed that 7 of them were drug-sensitive and the remaining 1 was resistant to rifampin and isoniazid. After follow-up of 24 months, 6 of them converted to sputum smear-positive.Our study showed that 90.4% (75/83) of the tuberculosis cases achieved real bacteriological negative result on biopsies after a short course chemotherapy, and the bacteriological positive cases on biopsy experienced 75.0% (6/8) sputum bacteriological recurrence. The result suggests that the evaluation criteria with sputum on therapeutic effect of pulmonary tuberculosis needs to be reassessed.