ABSTRACT
Dynamic control of heat flow for applications in thermal management has attracted much interest in fields such as electronics and thermal engineering. Spin-chain ladder cuprates are promising materials to realize dynamic control of heat flow, since their magnon thermal conductivity is sensitive to the hole density in the spin ladders, which can be dynamically controlled by an external field. Here, we demonstrate the electric control of heat flow using a polycrystalline cuprate film and an ionic liquid. The results showed that a voltage application to the interface causes imperfectly recoverable decreases in both the thermal conductance of the film and the peak due to magnons in the Raman spectra. This result may be attributed to an increase in the hole density in the spin ladders. This report highlights that magnon thermal conduction has potential for the development of advanced thermal management applications.
ABSTRACT
Deep veins (DVs) can be compressed by a uterus enlarged with fibroids. The purpose of this study was to assess the degree of luminal narrowing of DVs caused by a myomatous uterus, and the change in DV narrowing in women with symptomatic fibroids after embolization using time-of-flight (TOF)-magnetic resonance venography (MRV). Twenty-nine consecutive women with symptomatic uterine fibroids underwent TOF-MRV and pelvic MRI before and 4 months after embolization. Based on the TOF-MRV, we evaluated the luminal narrowing of three DVs, including the inferior vena cava, and the bilateral common and external iliac veins, and divided the findings into three grades. The scores for each DV were added for each patient (lowest, 0; highest, 6). DV scores and symptom severity (SS) scores were compared between the baseline and 4 months after embolization using the paired t-test. The relationship between DV scores and uterine volume was investigated using Pearson's test. DV scores decreased significantly, from 1.52 +/- 1.70 at baseline to 0.93 +/- 1.56 at 4 months after embolization (p = 0.004). The uterine volume decreased from 948 +/- 647 mL at baseline to 617 +/- 417 mL at 4 months after embolization (p < 0.001). DV score correlated with uterine volume (r = 0.856, p < 0.001). SS scores decreased from 54.5 +/- 14.6 at baseline to 26.8 +/- 15.4 at 4 months after embolization (p < 0.001). In conclusion, the degree of luminal narrowing of DVs caused by a uterus with fibroids is correlated with the uterine volume. Uterine artery embolization may induce an improvement of luminal narrowing of DVs due to a reduction of the myomatous uterus volume.
