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Masonry fences that tilt or lean have been recognized as potential dangers during earthquakes, making it essential to investigate their structural durability and ability to withstand seismic occurrences. In this study, a leaning U-shaped masonry fence wall structure is modeled by the reference of field surveys, and its seismic behavior is analyzed through dynamic shaking table tests as well as analytical approaches. The evolution of crack damage and changes in natural frequencies and hysteretic responses are analyzed to identify seismic behaviors of the leaning walls. As a result, the leaning causes asymmetric results between the side walls of the structure and introduces new concerns regarding seismic vulnerability. This study contributes to understanding the seismic characteristics and risks associated with leaning masonry fence walls, providing valuable insights for evaluating the hazards caused by leaning.

Mechanochromic smart membranes capable of optical modulation have great potential in smart windows, artificial skins, and camouflage. However, the realization of high-contrast optical modulation based on light scattering activated at a low strain remains challenging. Here, we present a strategy for designing mechanochromic scattering membranes by introducing a Young’s modulus mismatch between the two interdigitated polydimethylsiloxane phases with weak interfaces in a periodic three-dimensional (3D) structure. The refractive index-matched interfaces of the nanocomposite provide a high optical transparency of 93%. Experimental and computational studies reveal that the 3D heterogeneity facilitates the generation of numerous nanoscale debonds or “nanogaps” at the modulus-mismatching interfaces, enabling incident light scattering under tension. The heterogeneous scatterer delivers both a high transmittance contrast of >50% achieved at 15% strain and a maximum contrast of 82%. When used as a smart window, the membrane demonstrates effective diffusion of transmitting sunlight, leading to moderate indoor illumination by eliminating extremely bright or dark spots. At the other extreme, such a 3D heterogeneous design with strongly bonded interfaces can enhance the coloration sensitivity of mechanophore-dyed nanocomposites. This work presents insights into the design principles of advanced mechanochromic smart membranes.

Transoral vestibular approach thyroidectomy using robotic system has advantages with articulating instrumentation. Transoral robotic thyroidectomy (TORT) can be done either using just two robot arms for instruments and an extra one for the endoscopic camera, or using three robot arms for instruments (third arm through axila) and an additional arm for the camera.

OBJECTIVE: To determine the prevalence of systemic damage in Korean patients with systemic lupus erythematosus (SLE) and to elucidate associations between possible risk factors and the presence of damage. METHODS: The Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) was used to quantify systemic damage in 588 patients who were enrolled consecutively at the Hospital for Rheumatic Diseases, Seoul, South Korea. The frequencies and means of each variable were compared using the chi-square test or Student t test between the presence and absence of damage. Multivariate models were used to investigate the relationship between possible risk factors (age, disease duration, and use of intravenous cyclophosphamide) and the presence of damage. RESULTS: Among the 588 patients, 244 (41.5%) exhibited damage at a mean of 54 months after onset of disease. The musculoskeletal (14.3% of patients) and renal (13.3%) systems were involved most frequently, followed by neuropsychiatric (10.7%), ocular (4.6%), and pulmonary (4.1%) system involvement. The presence of damage was associated with higher age, longer disease duration, and a high frequency of intravenous cyclophosphamide use. CONCLUSION: Systemic damage in at least one of the items of the SDI was present in 41.5% of our Korean patients with SLE, this damage being significantly more prevalent in patients who were older, had longer disease duration, and received more intravenous pulses of cyclophosphamide.