Continuous monitoring of an arterial pulse using a pressure sensor attached on the epidermis is an important technology for detecting the early onset of cardiovascular disease and assessing personal health status. Conventional pulse sensors have the capability of detecting human biosignals, but have significant drawbacks of power consumption issues that limit sustainable operation of wearable medical devices. Here, a self-powered piezoelectric pulse sensor is demonstrated to enable in vivo measurement of radial/carotid pulse signals in near-surface arteries. The inorganic piezoelectric sensor on an ultrathin plastic achieves conformal contact with the complex texture of the rugged skin, which allows to respond to the tiny pulse changes arising on the surface of epidermis. Experimental studies provide characteristics of the sensor with a sensitivity (≈0.018 kPa ), response time (≈60 ms), and good mechanical stability. Wireless transmission of detected arterial pressure signals to a smart phone demonstrates the possibility of self-powered and real-time pulse monitoring system.

Additional surgeries for implantable biomedical devices are inevitable to replace discharged batteries, but repeated surgeries can be a risk to patients, causing bleeding, inflammation, and infection. Therefore, developing self-powered implantable devices is essential to reduce the patient's physical/psychological pain and financial burden. Although wireless communication plays a critical role in implantable biomedical devices that contain the function of data transmitting, it has never been integrated with in vivo piezoelectric self-powered system due to its high-level power consumption (microwatt-scale). Here, wireless communication, which is essential for a ubiquitous healthcare system, is successfully driven with in vivo energy harvesting enabled by high-performance single-crystalline (1 − x)Pb(Mg 1/3 Nb 2/3 )O 3 −(x)Pb(Zr,Ti)O 3 (PMN-PZT). The PMN-PZT energy harvester generates an open-circuit voltage of 17.8 V and a short-circuit current of 1.74 µA from porcine heartbeats, which are greater by a factor of 4.45 and 17.5 than those of previously reported in vivo piezoelectric energy harvesting. The energy harvester exhibits excellent biocompatibility, which implies the possibility for applying the device to biomedical applications.

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Jet cross sections have been measured for the first time in proton-proton collisions at a centre-of-mass energy of 7 TeV using the ATLAS detector. The measurement uses an integrated luminosity of 17 nb −1 recorded at the Large Hadron Collider. The anti-k t algorithm is used to identify jets, with two jet resolution parameters, R = 0.4 and 0.6. The dominant uncertainty comes from the jet energy scale, which is determined to within 7% for central jets above 60 GeV transverse momentum. Inclusive single-jet differential cross sections are presented as functions of jet transverse momentum and rapidity. Dijet cross sections are presented as functions of dijet mass and the angular variable χ. The results are compared to expectations based on next-toleading-order QCD, which agree with the data, providing a validation of the theory in a new kinematic regime.