We have recently developed a mobile brain imaging method (MoBI), that allows for simultaneous recording of brain and body dynamics of humans actively behaving in and interacting with their environment. A mobile imaging approach was needed to study cognitive processes that are inherently based on the use of human physical structure to obtain behavioral goals. This review gives examples of the tight coupling between human physical structure with cognitive processing and the role of supraspinal activity during control of human stance and locomotion. Existing brain imaging methods for actively behaving participants are described and new sensor technology allowing for mobile recordings of different behavioral states in humans is introduced. Finally, we review recent work demonstrating the feasibility of a MoBI system that was developed at the Swartz Center for Computational Neuroscience at the University of California, San Diego, demonstrating the range of behavior that can be investigated with this method.

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Conjugated polymers (CPs) with strong near-infrared (NIR) absorption and high heat conversion efficiency have emerged as a new generation of photothermal therapy (PTT) agents for cancer therapy. An efficient strategy to design NIR absorbing CPs with good water dispersibility is essential to achieve excellent therapeutic effect. In this work, poly[9,9-bis(4-(2-ethylhexyl)phenyl)fluorene-alt-co-6,7-bis(4-(hexyloxy)phenyl)-4,9-di(thiophen-2-yl)-thiadiazoloquinoxaline] (PFTTQ) is synthesized through the combination of donor-acceptor moieties by Suzuki polymerization. PFTTQ nanoparticles (NPs) are fabricated through a precipitation approach using 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG2000 ) as the encapsulation matrix. Due to the large NIR absorption coefficient (3.6 L g(-1) cm(-1) ), the temperature of PFTTQ NP suspension (0.5 mg/mL) could be rapidly increased to more than 50 °C upon continuous 808 nm laser irradiation (0.75 W/cm(2) ) for 5 min. The PFTTQ NPs show good biocompatibility to both MDA-MB-231 cells and Hela cells at 400 μg/mL of NPs, while upon laser irradiation, effective cancer cell killing is observed at a NP concentration of 50 μg/mL. Moreover, PFTTQ NPs could efficiently ablate tumor in in vivo study using a Hela tumor mouse model. Considering the large amount of NIR absorbing CPs available, the general encapsulation strategy will enable the development of more efficient PTT agents for cancer or tumor therapy.

In the present study, novel dry-contact sensors for measuring electro-encephalography (EEG) signals without any skin preparation are designed, fabricated by an injection molding manufacturing process and experimentally validated. Conventional wet electrodes are commonly used to measure EEG signals; they provide excellent EEG signals subject to proper skin preparation and conductive gel application. However, a series of skin preparation procedures for applying the wet electrodes is always required and usually creates trouble for users. To overcome these drawbacks, novel dry-contact EEG sensors were proposed for potential operation in the presence or absence of hair and without any skin preparation or conductive gel usage. The dry EEG sensors were designed to contact the scalp surface with 17 spring contact probes. Each probe was designed to include a probe head, plunger, spring, and barrel. The 17 probes were inserted into a flexible substrate using a one-time forming process via an established injection molding procedure. With these 17 spring contact probes, the flexible substrate allows for high geometric conformity between the sensor and the irregular scalp surface to maintain low skin-sensor interface impedance. Additionally, the flexible substrate also initiates a sensor buffer effect, eliminating pain when force is applied. The proposed dry EEG sensor was reliable in measuring EEG signals without any skin preparation or conductive gel usage, as compared with the conventional wet electrodes.