Realization of advanced bio-interactive electronic devices requires mechanically compliant sensors with the ability to detect extremely large strain. Here, we design a new multifunctional carbon nanotube (CNT) based capacitive strain sensors which can detect strains up to 300% with excellent durability even after thousands of cycles. The CNT-based strain gauge devices exhibit deterministic and linear capacitive response throughout the whole strain range with a gauge factor very close to the predicted value (strictly 1), representing the highest sensitivity value. The strain tests reveal the presented strain gauge with excellent dynamic sensing ability without overshoot or relaxation, and ultrafast response at sub-second scale. Coupling these superior sensing capabilities to the high transparency, physical robustness and flexibility, we believe the designed stretchable multifunctional CNT-based strain gauge may have various potential applications in human friendly and wearable smart electronics, subsequently demonstrated by our prototypical data glove and respiration monitor.R ecent developments in flexible and stretchable electronics, either through structural consideration or by exploring novel materials 1,2 , have imparted otherwise rigid and brittle electronic devices mechanical compliance and bio-compatibility, paving the way for energy-efficient, lightweight, portable, wearable and even implantable electronics 3 . Examples include stretchable and large area display that can undergo complex deformations 4 , bio-inspired material and structural designs that enable bionic functions 5 , and printable sensory system capable of detecting planar strains, normal pressure, temperature, light, moisture and chemical/biological species 6 . Multifunctional sensors, in particular, with sensing abilities akin to or beyond those of human skin 6-12 , are essential for applications such as interactive electronics 13 , structural health monitoring 14 , smart clothing 15 , robotic systems with advanced sensing capabilities 16 , human motion detection 8 and so on. Among the various types of sensors, strain gauge is one of the most important smart sensors, which have been widely used in the measurements of strain, acceleration and tension, as well as structural health monitoring. Conventional strain gauges, made of metal foils, register resistance changes under tensile strains. Actually, mechanical compliance and large strain range (?5%), obviously not the case of metal foils, are required to meet the demands of wearable electronics 15 , human motion detection 8 and interactive robots 17 . Although mercury-in-rubber strain gauge has been used in the biological measurements for decades 18 , the maximum strain limit and toxicity of mercury still block their practically wide applications. In addition, the combination of conformability and optical transparency will facilitate intelligent electronics and self-powered robot where strain sensors are integrated with optoelectronic devices and direct observation through the devices is ne...

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Cu2 MoS4 nanosheets are synthesized by a solvothermal method in which the Cu2 O starting material acts as a sacrificial template. The microstructure of the Cu2 MoS4 nanosheets is characterized at the atomic level, and the growth mechanism is monitored at the nanoscale through systematic time-dependent experiments. As a result, the unprecedented observation of the allotropic phase change in Cu2 MoS4 that occurs during the solvothermal process is possible.

Analysis of spatial access to healthcare services is critical for effective health resource planning. Gravitybased spatial access models have been widely used to estimate spatial access to healthcare services. Among them, the floating catchment area (FCA) methods have been proved to be informative and helpful to the designation of Health Professional Shortage Areas (HPSAs). This article integrates the Huff Model with the FCA method to articulate population selection on services. Through the proposed approach, population demand on healthcare services is adjusted by a Huff Model-based selection probability that reflects the impacts of both distance impedance and service site capacity. The new approach moderates the over-or under-estimating of population demand that occurred with previous methods. Furthermore, the method uses a continuous distance impedance weight function instead of the arbitrarily defined subzones of previous studies. A case study of spatial access to primary care in Springfield, MO, showed that the proposed method can effectively moderate the population demand on service sites and therefore can generate more reliable spatial access measures.

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In this work, we investigated the structure and morphology formation in crystalline–crystalline diblock copolymer of poly(l-lactide)-block-poly(ethylene glycol) (PLLA-b-PEG) on different length scales with optical microscopy (OM), atomic force microscopy (AFM), synchrotron time-resolved small-angle X-ray scattering (TR-SAXS) and wide-angle X-ray scattering (WAXS) methods. The PLLA-b-PEG copolymer with 5000 of number-average of molecular weight of PLLA and PEG blocks was used in this work. The structure and morphology of PLLA-b-PEG copolymers were formatted by a two-step crystallization process: i.e., the PLLA block crystallized fully at 110 °C in the first step, and then the PEG block crystallized fully at 30 °C in the second step. The OM, AFM, and SAXS results indicated that the PEG block crystallized in the multilength scales amorphous regions confined by PLLA crystals. The PEG block crystallized not only in the interlamellar regions of PLLA crystals, but also in the interfibrillar regions of PLLA. However, the subsequent crystallization of PEG block did not alter the foregoing spherulitic morphology of PLLA on the micrometer scale.

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