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The potential impact of elevated intra-abdominal pressure (IAP) on residual renal function (RRF) has not been determined. The objective of this study was to investigate the relationship between IAP and the rate of RRF decline in newly initiated peritoneal dialysis (PD) patients, and to identify the optimal IAP threshold value for delaying the deterioration of RRF. A cohort of 62 newly initiated PD patients who completed both 6- and 12-month follow-up evaluations was obtained using the Durand method. A logistic regression model was used to identify variables associated with a rapid decline in RRF. Receiver operating characteristic (ROC) curves were generated to determine the optimal threshold value. Another retrospective cohort analysis was performed to validate the identified critical value. For each 1 cmH2O increase in IAP, the risk of a rapid decline in the RRF increased by a factor of 1.679. Subsequent analysis revealed that patients in the high IAP group had more significant decreases in residual renal estimated glomerular filtration rate (eGFR) (Z = −3.694, p < 0.001) and urine volume (Z = −3.121, p < 0.001) than did those in the non-high IAP group. Furthermore, an IAP ≥15.65 cmH2O was a robust discriminator for the prediction of the rate of RRF decline. Patients in the high IAP group experienced a more rapid decline in RRF. Additionally, an optimal critical pressure of 15.65 cmH2O was identified for predicting the rate of RRF decline. IAP, as one of the factors contributing to the rapid decline in RRF in the first year of PD, should be given due attention. [ABSTRACT FROM AUTHOR]

The bonding of thick Cu and AlN is necessary in power modules with the development of high‐frequency communication technology. In this work, 2 mm‐thick Cu was successfully bonded with AlN by using Sn9Zn solder with the assistance of ultrasonication at 230°C. Results showed that an AlN/Sn9Zn/Cu joint without crack was manufactured with a cooling rate of 7°C/min. Nonreactive wetting was realized between AlN and Sn9Zn, forming an amorphous transition layer. CuZn2 and CuZn were formed at the Sn9Zn/Cu interface. A joint with the highest bonding strength of 30.07 MPa was obtained, in which the AlN/Sn9Zn interface was no longer the weakest location. This work provides a low‐temperature manufacturing method for thick Cu/AlN joints. [ABSTRACT FROM AUTHOR]

A new approach was adopted to improve the corrosion behavior of the chromium nitride (CrNx) hard coating through magnetron sputtering deposition at different nitrogen flow rates. The influence of the nitrogen flow rates on the chemical composition, microstructure, mechanical property and corrosion behavior in artificial seawater of the CrNx coatings was investigated. The results show that with the increase of the nitrogen flow rates, the growth structure of the coatings varied from dense granular growth to coarse columnar growth. Increasing the nitrogen flow rates was helpful to decrease the Cr/N ratio and induce the phase transforming from mixed hexagonal Cr2N and face-centered cubic CrN to single CrN. However, the coatings under different nitrogen flow rates significantly improved the corrosion resistance and hardness of the steel substrate. Furthermore, at high nitrogen flow rate, the coating had high corrosion velocity and low protective capability against the substrate corrosion due to the fast corrosion channels acted by the columnar grain boundaries. While at the middle nitrogen flow rate, the coating with CrN phase, densely granular growth structure and moderate grain size resulted in excellent corrosion resistance and highest hardness. [ABSTRACT FROM AUTHOR]

Background and objectives: The urban underground complex integrates comprehensive architecture and subterranean space, presenting physical and psychological complexities. To mitigate the negative experiences associated with this complexity, we need to explore, in depth, how the built environmental elements of underground complexes affect user perception to design a comfortable, healthy, and biophilic underground space. Methods: We selected Tianfu Square, a typical underground complex in Chengdu, China, as the empirical case. We identified 26 key environmental indicators affecting user perception and designed Kano and satisfaction questionnaires based on these indicators. A total of 476 questionnaires were distributed to collect data on users' attitudes towards changes in element quality and their satisfaction levels. By integrating the Kano model and IPA method, we defined the perceptual attributes of elements based on their impact on user experiences and assessed the alignment between element attributes and satisfaction. Results: We categorized the elements into five perceptual types: attractive, one-dimensional, indifferent, must-be, and reverse attributes, and assigned corresponding importance levels. We then compared the importance and performance scores of these elements, evaluated their satisfaction alignment, identified elements needing optimization, and proposed improvement strategies. Implications: This research provides valuable guidance for designers on how various built environment elements in underground spaces influence user perceptions, with practical implications for urban underground complex planning and design. [ABSTRACT FROM AUTHOR]