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Phosphate fertilizers are applied to the soil surface, especially in vineyards in production in subtropical regions. Nowadays, phosphorus (P) is not incorporated into the soil to avoid mechanical damage to the root system in orchards. However, over the years, successive surface P applications can increase the P content only in the topsoil, maintaining low P levels in the subsurface, which can reduce its use by grapevines. For this reason, there is a need to propose strategies to increase the P content in the soil profile of established orchards. The study aimed to evaluate the effect of management strategies to (i) increase the P content in the soil profile; (ii) enhance the grape production; and (iii) maintain the grape must composition. An experiment on the 'Pinot Noir' grape in full production was carried out over three crop seasons. The treatments were without P application (C), P on the soil surface without incorporation (SP), P incorporated at 20 cm (IP20), P incorporated at 40 cm (IP40), and twice the P dose incorporated at 40 cm (2IP40). The P concentration in leaves at flowering and veraison, P content in the soil, grape production and its components, and chemical parameters of the grape must (total soluble solids, total polyphenols, total titratable acidity, total anthocyanins, and pH) were evaluated. The P concentration in leaves did not differ among the P application modes. The application of P associated with soil mobilization, especially at 20 cm depth, increased grape production. The P application modes did not affect the values of the chemical parameters of the grape must except for the total anthocyanins, which had the highest values when the vines were subjected to 2IP40. Finally, the P application and incorporation into the soil profile was an efficient strategy for increasing the grape production in full production vineyards.

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PURPOSE: The aim of this randomized controlled clinical trial was to evaluate the 3-year clinical performance of a universal adhesive (Clearfil Universal Bond Quick (CUBQ); Kuraray Noritake) when restoring non-carious cervical lesions (NCCLs) using two different application modes (etch-and-rinse vs self-etch with prior selective enamel etching). MATERIALS AND METHODS: Fifty-one patients participated in this study. A total of 251 NCCLs (n = 251) were assigned to two groups: 1) CUBQ applied in etch-and-rinse mode (n = 122; CUBQ-ER) and 2) CUBQ applied in self-etch mode with prior selective etching of enamel with phosphoric acid (n = 129; CUPQ-SEE). The same resin composite, Clearfil Majesty ES-2 (Kuraray Noritake), was used for all restorations. The restorations were evaluated at baseline, 1 and 3 years using FDI criteria: marginal staining, fracture and retention, marginal adaptation, post-operative sensitivity and recurrence of caries. Statistical analysis was performed using a logistic regression model with generalized estimating equations (2-way GEE model). RESULTS: The patient recall rate at 3 years was 90%. After 3 years, both groups presented an increase in the percentage of small but still clinically acceptable marginal defects (CUBQ-ER: 67%, CUBQ-SEE: 63.2%) and marginal staining (CUBQ-ER: 32.6%, CUBQ-SEE: 31.7%). The overall success rate was 82.6% and 83.8% for CUBQ-ER and CUBQ-SEE, respectively. In total, 38 restorations (19 CUBQ-ER, 19 CUBQ-SEE) failed because of loss of retention, fracture, severe marginal defect and/or marginal discoloration. A retention rate of 87.2% and 86.3% was recorded for CUBQ-ER and CUBQ-SEE, respectively. No significant difference was observed between the two bonding-mode groups for any of the evaluated parameters. CONCLUSION: After 3 years of clinical service, Clearfil Universal Bond Quick performed similarly in etch-and-rinse and self-etch modes with prior selective enamel etching.

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PURPOSE: To evaluate the 24-month clinical performance of Adhese Universal (ADH) (Ivoclar Vivadent) using two different application modes (etch-and-rinse vs self-etch) when restoring non-carious cervical lesions. MATERIALS AND METHODS: Twenty-six patients participated in this study. A total of 117 non-carious cervical lesion restorations (N = 117) were assigned to two groups: 1) ADH in the etch-and-rinse mode (n = 59) and 2) ADH in the self-etch mode (n = 58). The same resin composite (Tetric EvoCeram, Ivoclar Vivadent) was used for all restorations. The restorations were evaluated at baseline and at 24 months using the World Dental Federation (FDI) criteria. The results were analyzed statistically using the McNemar test (α = 0.05) and a generalized estimating equation. RESULTS: In self-etch mode, significant differences were found for marginal coloring (p = 0.002), marginal adaptation (p = 0.031), and hypersensitivity (p = 0.031) between baseline and the end of the 24-month period. In the etch-and-rinse mode, significant differences were found for marginal coloring (p = 0.004), fractures/retention (p = 0.002), marginal adaptation (p = 0.002), and hypersensitivity (p = 0.000). Significant differences were also detected between groups at 24 months for fractures/retention (p = 0.001). At 24 months, 10 restorations of the etch-and-rinse group were lost and 2 restorations of the self-etch group were lost. CONCLUSION: In terms of fractures and retention criteria, this universal adhesive obtained better results when applied in self-etch mode than in etch-and-rinse mode.

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A rapid, sensitive and effective supercritical fluid chromatographic-tandem mass spectrometry (SFC-MS/MS) method was developed to analyze thiacloprid for the first time. The SFC-MS/MS conditions were optimized with the ultra-performance convergence chromatography (UPC2) BEH column (100 mm × 3.0 mm, 1.7 µm particle size) and thiacloprid was eluted at 1.22 min in gradient mode with CO2/methanol as mobile phase. The 0.1% formic acid in methanol (v/v) was used as postcolumn compensation solution to improve sensitivity. The ABPR pressure, flow rate of mobile phase and flow rate of compensation pump were set at 1800 psi, 1.8 mL/min, and 0.1 mL/min, respectively. The average recoveries of thiacloprid in soil at four spiking levels (5, 10, 100, 1000 µg/kg) ranged between 78.8% and 107.1% with relative standard deviations (RSDs) lower than 12.2% and the limit of quantitation (LOQ) was 5 µg/kg. The proposed method can distinctly improve the analysis efficiency by 2-12 times and reduce the solvent consumption by 5%-95% compared with reported methods. It was applied to investigate the dissipation rates of thiacloprid in greenhouse vegetables and soil under different application modes. The half-lives of thiacloprid in cucumber and soil were 9.55-20.44 days and 3.74-9.14 days separately under different application modes, 10.60 days in tomato under foliar spraying. The residues in vegetables under root irrigation were all less than that under foliar spraying. The results could offer useful data for risk assessment of thiacloprid in agricultural production.

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