Diagnostic Performance of Ultrasound Computer-Aided Diagnosis Software Compared with That of Radiologists with Different Levels of Expertise for Thyroid Malignancy: A Multicenter Prospective Study.

The aim of the work described here was to evaluate the diagnostic performance of ultrasound thyroid computer-aided diagnosis (CAD) software. This multicenter prospective study included 494 patients (565 thyroid nodules) who underwent surgery or biopsy after ultrasonography at four hospitals from January 2019 to September 2019. The diagnostic performance metrics of different readers were calculated and compared with the pathologic results. The sensitivity of CAD was outstanding and was equivalent to that of a senior radiologist (90.51% vs. 88.47%, p > 0.05). The area under the curve of CAD was equivalent to that of a junior radiologist (0.748 vs. 0.739, p > 0.05). However, the specificity was only 49.63%, which was lower than those of the three radiologists (75.56%, 85.93% and 90.37% for the junior, intermediate and senior radiologists, respectively). The diagnostic performance of the junior radiologist was significantly improved with the aid of CAD (junior + CAD). The sensitivity and area under the curve of junior + CAD were improved from 72.20% to 89.93% and from 0.739 to 0.816, respectively (both p values <0.05), and the positive predictive value, negative predictive value and κ coefficient improved from 76.3% to 78.6%, 82.0% to 86.8% and 0.394 to 0.511, respectively. Though specificity slightly decreased from 75.56% to 73.33%, the difference was not statistically significant (p > 0.05). In general, the clinical application value of CAD is promising, and its instrumental value for junior radiologists is significant.

[Dynamics of active organic carbon in a paddy soil under different rice farming modes].

A field experiment was conducted to study the dynamics of dissolved organic carbon (DOC), readily oxidizable organic carbon (ROC), and microbial biomass carbon (MBC) in a paddy soil under integrated rice-duck farming (RD), intermittent irrigation (RW), and conventional flooded irrigation (CK), the three rice farming modes typical in southern China. Under these three farming modes, the soil DOC and MBC contents reached the highest during the period from rice booting to heading, while the soil ROC content had less change during the whole rice growth period. Two-factor variance analysis showed that soil MBC was greatly affected by rice growth stage, soil DOC was greatly affected by rice growth stage and farming mode, and soil ROC was mainly affected by farming mode. Comparing with CK, RD significantly increased the soil DOC and ROC contents and their availability, while RW significantly decreased the soil DOC content and its availability but increased the soil ROC content and its availability. No significant differences were observed in the soil MBC and microbial quotient among RD, RW, and CK.

[Individual and interactive effects of aluminum, selenium, silicon and phosphorus on rice seedlings growth].

By using quadratic orthogonal rotation combinatorial design, and taking aluminum (Al), selenium (Se), silicon (Si), and phosphorus (P) as test factors, the regression models of test factors and the survival rate (SR), shoot mass per hundred plants (SMHP), root mass per one hundred plant seedlings (RMHP), and proline contents (PC) of rice seedlings were established, with the individual and interactive effects of the factors analyzed. The individual effects of test factors on the SR, SMHP, RMHP, and PC of rice seedlings decreased in the order of Al > P > Se > Si. Al showed negative effect, while Se, Si, and P showed positive effect. There were no significant interactive effects between the factors, except between Al and Si. Simulated optimization test showed that rice seedlings could grow better in an Al-containing solution when the Al was within the range of 0.587-0.913 mmol L(-1), Se was of 0.478-0.564 mg x L(-1), Si was of 0.613-1.069 mmol x L(-1), and P was of 2.252-2.657 mmol L(-1).