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Gold nanorods can be used as remote controlled nanoheaters delivering the right amount of thermal treatment to cancer cells, thanks to diamond nanocrystals used as temperature sensors.

Precise targeting biological molecules, such as cancer cells, for treatment is a challenge, due to their sheer size. Now, the authors have proposed an advanced solution, based on a novel combination of previously used techniques, which can potentially be applied to thermal cancer therapy. The authors presented in this work an improved sensing technique for nanometre-scale heating and temperature sensing. Using a chemical method to attach gold nanorods to the surface of a diamond nanocrystal, they have invented a new biocompatible nanodevice. It is capable of delivering extremely localised heating from a near-infrared laser aimed at the gold nanorods, while accurately sensing temperature with the nanocrystals.The novelty of this study is that it shows that it is possible to use diamond nanocrystals as hypersensitive temperature sensors with a high spatial resolution—ranging from 10 to 100 nanometres—to monitor the amount of heat delivered to cancer cells.

Energy transport at the nano/quantum scale has a long history of research, with significant interest being paid in the debate over whether quantum coherence plays a role in the efficiency of exciton transport in photosynthetic complexes. Much attention has also turned to improving energy transport for man-made energy harvesting systems and nanodevices, such as in solar cells and quantum dot arrays.

Achieving directed quantum transport permits far superior collection of the deposited energy. The study of quantum ratchets shows how directed energy transport is achievable in quantum dot arrays. Recent experimental work on light harvesting molecules have implicated the role of discrete mechanical modes in enhancing the energy transport through dipole arrays, but say less about directed transport. Here the authors bring together these two apparently unrelated models to present a scheme for a new type of quantum engine. Utilising both excitonic and vibrational motions it is shown that the resulting coherent mechanical dynamics causes directed enhanced energy transport towards one end of the exciton chain. The quantum engine is autonomous, requiring no external pumping or modulation but works off the initial charge on the exciton chain which excites the vibrational motion.

Scientists model the manner in which a liquid wets fibres, gaining useful insights for improving glass wool properties

Sandcastles are a prime example of how adding a small amount of liquid to a granular material changes its characteristics. But understanding the effect of a liquid wetting randomly oriented fibres in a fibrous medium remains a mystery. Relevant to the building industry, which uses glass wool, for instance, this phenomenon can be better understood by studying the behaviour of a liquid trapped between two parallel fibres. It can either remain in the shape of a drop or spread between the fibres into a long and thin column of liquid. Now, the authors have demonstrated that the spreading of the liquid is controlled by three key parameters: the amount of liquid on the fibres, the fibres’ orientation and the minimum distance between them. These findings, based on experimental and modelling work, were published recently.