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Currently, research on superparamagnetic iron oxide nanoparticles (SPIONs) for magnetic hyperthermia applications is steadily increasing.

Among the number of hyperthermia materials, magnetic nanoparticles have received much attention. In this work, we studied the heating characteristics of uniform Fe@Fe3O4 core–shell nanoparticle under near-infrared laser irradiation and external AC magnetic field applying. The Fe@Fe3O4 core–shell nanoparticles were prepared by thermal decomposition of iron pentacarbonyl and followed by controlled oxidation. The prepared uniform particles were further coated with dimercaptosuccinic acid to make them well dispersed in water. Near-infrared derived photothermal study of solutions containing a different concentration of the core–shell nanoparticles was made by using 808 nm laser Source. Additionally, magnetic hyperthermia ability of the Fe@Fe3O4 nanoparticle at 150 kHz and various oersted (140–180 Oe) condition was systemically characterized. The Fe@Fe3O4 nanoparticles which exhibited effective photo and magnetic hyperthermia are expected to be used in biomedical application.

Nowadays, stretchable, flexible and wearable strain sensors are becoming more and more important for their abilities to monitor human health and body motions. However, it still exists some challenges to develop a new type of strain sensor with high sensitivity, the properties of anti-harsh environments and multidirectional monitoring. Here, we put forward a flexible, multi-functional, wearable and conductive nanofiber composite (WCNC) strain senor with handy preparation method, consisting of elastic thermoplastic polyurethane (TPU) with decorated acid modified carbon nanotubes (ACNTs), coupled silver nanowires (AgNWs) and solidified polydimethylsiloxane (PDMS). The sequential decorations of ACNTs, AgNWs and PDMS enhance the conductivity, superhydrophobicity, and strain sensing performance of the TPU-based nanofibrous membrane. The WCNC (TPU/ACNTs/ AgNWs/ PDMS) possesses a quite low resistance about 1.22 Ω/cm2 (conductivity is up to 3506.8 S/m), superior superhydrophobicity (contact angle is up to 153.04°) and self-cleaning property. Furthermore, the WCNC strain sensor possesses high sensitivity and large working strain (gauge factor is nearly 1.36 × 105 with the working strain ranging from 38% to 100%), which illustrates that the WCNC has a quite large work strain under extremely high GF, and has never been reported before. On account of its outstanding sensing performance, the WCNC can be used to monitor the different movements of human bodies and simultaneously monitor sensor signals in multiple vertical directions, achieving more accurate results.

Additional file 1: Fig. S1. DLS measurements data of the DMSA coated Fe@Fe3O4 nanoparticles. Hydrodynamic disameter ( above ) were meassured as 18.45nm and its zeta potential ( below ) value is − 23.5mV due to thier carboxylate end. Table S1. Total heat generation and heat conversion efficiency calcuated by simple mathematical method and the result. Table S2. Table about the maximum temperature raise, total heat generation and efficiency from photothermal repeating test. Figure S2. (a) Fe@Fe3O4 in PBS after 48 h (left), redispersed Fe@Fe3O4 by simple agitation (right). (b) Photothermal characterization of the as-prepared Fe@Fe3O4 and Fe@Fe3O4 stored in PBS for 48 hours. The concentration is 10 mg/ml. Table S3. Comparison table between the as-prepared Fe@Fe3O4 nanoparticles and other photothermal nanoparticles reported in literatures.

A variety of oscillations are observed in pancreatic islets.We establish a model, incorporating two oscillatory systems of different time scales: One is the well-known bursting model in pancreatic beta-cells and the other is the glucose-insulin feedback model which considers direct and indirect feedback of secreted insulin. These two are coupled to interact with each other in the combined model, and two basic assumptions are made on the basis of biological observations: The conductance g_{K(ATP)} for the ATP-dependent potassium current is a decreasing function of the glucose concentration whereas the insulin secretion rate is given by a function of the intracellular calcium concentration. Obtained via extensive numerical simulations are complex oscillations including clusters of bursts, slow and fast calcium oscillations, and so on. We also consider how the intracellular glucose concentration depends upon the extracellular glucose concentration, and examine the inhibitory effects of insulin., 11 pages, 16 figures

We study the synchronization phenomena in a system of globally coupled oscillators with time delay in the coupling. The self-consistency equations for the order parameter are derived, which depend explicitly on the amount of delay. Analysis of these equations reveals that the system in general exhibits discontinuous transitions in addition to the usual continuous transition, between the incoherent state and a multitude of coherent states with different synchronization frequencies. In particular, the phase diagram is obtained on the plane of the coupling strength and the delay time, and ubiquity of multistability as well as suppression of the synchronization frequency is manifested. Numerical simulations are also performed to give consistent results.