The absorption of acoustic energy by internal degrees of freedom of short chains is proposed as a new viable mechanism of ultrasound attenuation in ferrofluids. It is demonstrated that even though the volume fraction of the chains may be quite small, such an effect may reach the order of magnitude of viscous damping. In addition, by investigating the statistical properties of dimers in ferrofluids, it is shown that an applied magnetic field modifies the sound attenuation in a highly anisotropic manner. The proposed mechanism provides new insight into the fundamental issue of colloidal response, and, in particular, may lead to its utilization in novel experimental concepts.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevLett.101.074505 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Spectral Content Effects Study in Non-Contact Resonance Ultrasound Spectroscopy.
Sensors (Basel)
January 2025
Department of Electronics Engineering, Kaunas University of Technology, 51368 Kaunas, Lithuania.
The application of spread-spectrum signals (arbitrary pulse width and position (APWP) sequences) in air-coupled resonant ultrasound spectroscopy is studied. It was hypothesized that spread-spectrum signal optimization should be based on te signal to noise ratio (SNR). Six APWP signal optimization criteria were proposed for this purpose.
View Article and Find Full Text PDFOral colon-targeted responsive chitosan/pectin-based nanoparticles propels the application of tofacitinib in colitis therapy.
Sci Rep
January 2025
School of Basic Medicine, Qingdao Medical College, Qingdao University, Qingdao, China.
Tofacitinib (Tof), a commercially available pan-Janus kinases inhibitor, is approved for the treatment of moderate to severe ulcerative colitis. However, its clinical application is limited due to dose-dependent systemic side effects. The present study aims to develop an efficient oral colon-targeted drug delivery systems using prebiotic pectin (Pcn) and chitosan (Csn) polysaccharides as a shell, with Tof loaded into a Bovine Serum Albumin (BSA) core, and improving it with chondroitin sulfate (Chs), thus constructing Tof@BSA-Chs-CP nanoparticles (NPs).
View Article and Find Full Text PDFThe maternal body mass index and first-trimester placental (vascular) development.
Placenta
December 2024
Department of Obstetrics and Gynecology, Erasmus MC, University Medical Center, Rotterdam, the Netherlands. Electronic address:
Background: Maternal obesity is associated with maternal complications, including hypertensive disorders of pregnancy (HDP), and related fetal complications, such as fetal growth restriction. During pregnancy, the placenta is one of the key regulators of embryonic and fetal growth. Previous studies mainly investigated placental growth by measuring postpartum placental weight.
View Article and Find Full Text PDFSequential Targeting Chondroitin Sulfate-Bilirubin Nanomedicine Attenuates Osteoarthritis via Reprogramming Lipid Metabolism in M1 Macrophages.
Adv Sci (Weinh)
January 2025
Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.
The infiltration and excessive polarization of M1 macrophages contribute to the induction and persistence of low-grade inflammation in joint-related degenerative diseases such as osteoarthritis (OA). The lipid metabolism dysregulation promotes M1 macrophage polarization by coordinating the compensatory pathways of the inflammatory and oxidative stress responses. Here, a self-assembling, licofelone-loaded nanoparticle (termed LCF-CSBN), comprising chondroitin sulfate and bilirubin joined by an ethylenediamine linker, is developed to selectively reprogram lipid metabolism in macrophage activation.
View Article and Find Full Text PDFKuanxiong Aerosol Attenuates Ischemic Stroke Injury via Modulation of the TRPV1 Channel.
Chin J Integr Med
January 2025
Department of Ultrasound in Medicine, the Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, 310009, China.
Objective: To evaluate the therapeutic effects of Kuanxiong Aerosol (KXA) on ischemic stroke with reperfusion and elucidate the underlying pharmacological mechanisms.
Methods: In vivo pharmacological effects on ischemic stroke with reperfusion was evaluated using the transient middle cerebral artery occlusion (t-MCAO) mice model. To evaluate short-term outcome, 30 mice were randomly divided into vehicle group (n=15) and KXA group (n=15).
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!