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In May 2023, direct observations of rip currents were conducted at Haeundae Beach, Korea, over a two-day period at six different stations using upward-facing Acoustic Doppler Current Profilers (ADCPs). The depth-averaged cross-shore velocity data were low-pass filtered with a 30-s cutoff period to eliminate wave-related motions. By applying 15-min boxcar averages, correlation analyses were performed to examine the relationship between three types of flow (cross-shore, onshore, and offshore) and three environmental factors (tide, wave, and wind). The analysis revealed that only one (R2-3) of the six stations had a high likelihood of rip current occurrence. Rip currents were defined as regions of offshore flow within the low-pass filtered time series of cross-shore velocities. For each identified rip current, three key kinematic features—maximum speed, duration, and distance—were estimated. Using specific thresholds for these features, hazardous rip currents were determined. Station R2-3 was the only station where hazardous rip currents were observed, which is consistent with the findings of the correlation analysis. Additionally, swells with a 15-s period were detected exclusively at R2-3 during the period of the hazardous rip currents, suggesting their significant role in the development of the observed rip currents. Furthermore, both Rip Index from the Rip Current Monitoring and Warning System and the CCTV Score from the Rip Current Checklist exceeded threshold values during this period, reinforcing the reliability of the method used. The potential influence of bound infragravity waves on the duration and variability of these rip currents was discussed. The rip currents observed at Haeundae Beach could be categorized as the "focused" type. [ABSTRACT FROM AUTHOR]

Feline hypertrophic cardiomyopathy (HCM) is a common heart disease affecting 10–15% of all cats. Cats with HCM exhibit breathing difficulties, lethargy, and heart murmur; furthermore, feline HCM can also result in sudden death. Among various methods and indices, radiography and ultrasound are the gold standards in the diagnosis of feline HCM. However, only 75% accuracy has been achieved using radiography alone. Therefore, we trained five residual architectures (ResNet50V2, ResNet152, InceptionResNetV2, MobileNetV2, and Xception) using 231 ventrodorsal radiographic images of cats (143 HCM and 88 normal) and investigated the optimal architecture for diagnosing feline HCM through radiography. To ensure the generalizability of the data, the x-ray images were obtained from 5 independent institutions. In addition, 42 images were used in the test. The test data were divided into two; 22 radiographic images were used in prediction analysis and 20 radiographic images of cats were used in the evaluation of the peeking phenomenon and the voting strategy. As a result, all models showed > 90% accuracy; Resnet50V2: 95.45%; Resnet152: 95.45; InceptionResNetV2: 95.45%; MobileNetV2: 95.45% and Xception: 95.45. In addition, two voting strategies were applied to the five CNN models; softmax and majority voting. As a result, the softmax voting strategy achieved 95% accuracy in combined test data. Our findings demonstrate that an automated deep-learning system using a residual architecture can assist veterinary radiologists in screening HCM. [ABSTRACT FROM AUTHOR]

Induction motors are the most common driving force for active mechanical components such as pumps and valves. When these motors are used in safety systems, which are normally on standby, monitoring the motors through nondestructive evaluation techniques is needed to guarantee their operability and system integrity. In this context, this study suggests a method for motor health monitoring at standstill through impedance analysis. Impedance change tendencies for various motor failure cases are investigated. To identify the tendencies, first an equivalent circuit (EC) of an induction motor is developed, and probable impedance changes for each failure case are estimated based on the developed EC. Then, the estimates are experimentally verified by reproducing the failures and measuring the impedance with an impedance analyzer. As the equivalence between the estimates and the experimental results is confirmed, unique tendencies in impedance changes for each failure case are characterized. The suggested method is expected to be useful in areas with access restriction, such as nuclear power plants (NPPs), as motor impedance can be measured from a distance without any disruption on-site. [ABSTRACT FROM PUBLISHER]

Chiral metal–organic frameworks are considered a useful platform in heterogeneous catalysis for enantioselective chemical transformations. However, it has been observed that the enantioselectivity is sensitive to the site at which the reaction takes place, even in a single crystal, since the chiral environment of the catalytic site varies according to its location, e.g., that of the surface is anisotropic, whereas that of the interior is isotropic. [ABSTRACT FROM AUTHOR]

Two chiral MOFs from the common Zn4O(COO)6 SBUs and the congeners of chiral ligands were synthesized and characterized. The overall structures are differentiated by the ligand dimensions. These MOFs obtained from the flexible enantiopure struts exhibited severe chirality attenuation during the assembly. [ABSTRACT FROM AUTHOR]

The article discusses the enantioselective catalysis of carbonyl ene reactions of substrate using heterogeneous catalysts which is based on metal-organic frameworks. Topics include the benefits of utilizing heterogeneous catalysts based metal-organic frameworks to conventional homogeneous system and the improvements to the reactions results when utilizing unscrambled mixed catalysts.

The assessment of guest-accessible volume in MOFs can be reliably done by using two-photon confocal fluorescence microscopy (TPM) with a tool-box of dyes with a wide range of sizes. It would be applicable to any porous materials, whose single-crystal structures are not available, or non-crystalline materials. [ABSTRACT FROM AUTHOR]

The chiral 3D MOFs resulted from the packing of chiral 1D SBBs were studied. It was demonstrated that the final packing pattern is sensitively dependent on the dimension of SBBs. In addition, we were able to identify a new plywood-like network from ligand 2H2exhibiting an unprecedented six-way chiral helical packing motif, which extends the list of invariant rod packings. [ABSTRACT FROM AUTHOR]