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This study aimed to explore the predictability of the most long‐lived tropical cyclone (TC) Freddy in 2023 while it traversed westward across the southern tropical Indian Ocean during the first 18 days of its existence. Global ensemble forecasts revealed southward track deflection and intensity underestimation of Freddy. We identified three key factors contributing to the limited predictability of Freddy, which are associated with the Mascarene High, Storm Dingani, and Freddy itself. The large track errors of Freddy can be attributed to the underestimated strength of the Mascarene High, the more northeastern position of Dingani, and the presence of excessively large or small sizes of Freddy. These findings were further validated through a high‐resolution regional model. Specifically, Freddy's track and intensity most closely matched the observations when these three factors were most closely represented. It underscores the pivotal role played by the interaction between TCs and multi‐scale systems in TC forecasts. Plain Language Summary: In 2023, Storm Freddy emerged as the most long‐lived tropical cyclone (TC) in record, lasting 35 days over the southern tropical Indian Ocean and spanning both weather and sub‐seasonal to seasonal time ranges. The primary objective of this study is to understand the factors contributing to the poor predictability of Freddy in forecasts spanning over 2 weeks. This holds significant importance as our understanding about the ability of the numerical models to predict long‐lived TCs remains limited. Using over 7,000 global ensemble forecasts from five global Numerical Weather Prediction (NWP) centers and a high‐resolution regional model, we identified three key factors contributing to the limited predictability of Freddy: the strength of the Mascarene High, the position of Storm Dingani (2023), and the size of Freddy. In large track‐error results of the global forecasts and regional simulations for Freddy, the strength of the Mascarene High was underestimated, Dingani was located further northeast, and Freddy was either too large or too small. Our investigation emphasizes the crucial role played by the interaction between the TC and multi‐scale systems in TC forecasts. This is meaningful for the improvement of Numerical Weather Prediction models to deal with extreme TC events in the future. Key Points: Due to the long lifespan of Storm Freddy, many forecasting challenges across several numerical models aroseThe limited predictability of Freddy was related to the underestimated Mascarene High and the more northeastern position of Storm DinganiThe inaccurately forecasted size of Freddy, whether excessively large or small, also contributed to the large track errors [ABSTRACT FROM AUTHOR]

Objective: To study the effects of universal adhesives and resin cement on the shear bond strength and durability of zirconia ceramics., Methods: Zirconia ceramics were sintered into 20 mm×10 mm×10 mm and 10 mm×10 mm×10 mm specimens. The experiment was divided into 12 groups. The two types of specimens were bonded using two variants of resin cement (RelyX Ultimate and Clearfil SAC self-adhesive resin cement), universal adhesives (non-adhesive, Scotchbond uni-versal adhesive, and Clearfil SE One adhesive), and storage conditions (water bath and water bath-thermal cycling). The shear bond strengths were tested, and the fracture morphologies were analyzed., Results: The cement (F=8.41, P<0.01) and adhesive (F=30.34, P<0.01) exerted a significant effect on the shear bond strength of zirconia, whereas storage condition showed no significant effect on this property (F=1.83, P=0.18). The lowest shear bond strength (14.02 MPa±6.86 MPa) was exhibited by the group treated with RelyX Ultimate resin cement, non-adhesive, and water bath-thermal cycling, whereas the highest shear bond strength (54.12 MPa±8.37 MPa) was displayed by the group treated with RelyX Ultimate resin cement, Scotchbond universal adhesive, and water bath-thermal cycling., Conclusions: Universal adhesives can improve the durability of the bonding of resin cement to zirconia. If non-self-adhesive resin cement is used without a universal adhe-sive, the durability of the bond will be greatly reduced.