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Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the development of intelligent transportation, driverless is another important means that will utterly change traditional travels in the future. In order to adapt to the large-scale and complex traffic environment of driverless, we propose a dynamic bidirectional A* algorithm for driverless navigation planning. On the basis of this, theoretical simulations under different traffic flow conditions are realized, and the feasibility of the algorithm is verified. The vehicular self-organizing network is an important development direction of driverless in the future. In order to verify the performance of the algorithm in the vehicular self-organizing network environment, we adopt the OMNeT++ and SUMO bidirectional coupling, and perform joint simulation experiments on the open source framework Veins. In the traffic states with different traffic densities, the path planned by the dynamic bidirectional A* algorithm in the Vanet environment can reduce travel time and improve travel efficiency more effectively than that of the traditional bidirectional A* algorithm. [ABSTRACT FROM AUTHOR]

We investigate the atomic structure and electronic properties of monolayers of copper phthalocyanines (CuPc) deposited on epitaxial graphene substrate. We focus in particular on hexadecafluorophthalocyanine (F16CuPc), using both theoretical and experimental (scanning tunneling microscopy - STM) studies. For the individual CuPc and F16CuPc molecules, we calculated the electronic and optical properties using density functional theory (DFT) and time-dependent DFT and found a red-shift in the absorption peaks of F16CuPc relative to those of CuPc. In F16CuPc, the electronic wavefunctions are more polarized toward the electronegative fluorine atoms and away from the Cu atom at the center of the molecule. When adsorbed on graphene, the molecules lie flat and form closely packed patterns: F16CuPc forms a hexagonal pattern with two well-ordered alternating α and β stripes while CuPc arranges into a square lattice. The competition between molecule-substrate and intermolecular van der Waals interactions plays a crucial role in establishing the molecular patterns leading to tunable electron transfer from graphene to the molecules. This transfer is controlled by the layer thickness of, or the applied voltage on, epitaxial graphene resulting in selective F16CuPc adsorption, as observed in STM experiments. In addition, phthalocyanine adsorption modifies the electronic structure of the underlying graphene substrate introducing intensity smoothing in the range of 2-3 eV below the Dirac point (ED) and a small peak in the density of states at ∼0.4 eV above ED. [ABSTRACT FROM AUTHOR]

Energy-autonomous smart electronics have been the focus of the next generation of the Internet of Things. Recently, advanced power technology with sustainable energy supply and pollution-free characteristics has become a research hotspot. Herein, to realize a reliable and unattended power unit, we propose a high-performance omnidirectional-sliding triboelectric-electromagnetic hybrid nanogenerator (OS-TEHNG) to convert the mechanical energy into electricity. The free-standing triboelectric nanogenerator (TENG) achieves a charge transfer of 24.4 μC in one cycle and a short-circuit current of 0.36 mA after optimizing the electrode structure. The TENG with 130 kΩ impedance allows efficient charging of energy storage units without complex power management modules (PMMs). The electromagnetic part achieves an open-circuit voltage of 300 V after optimization. OS-TEHNG achieves a peak power density of 1568.4 W/m3 and an average power density of 352.3 W/m3 at 2 Hz. As a result, OS-TEHNG charges a 1 mF capacitor to 46 V within 8 s. The strong power supply capability allows OS-TEHNG to charge smartwatches and phones. Furthermore, a completely self-powered wireless keyboard with a PMM and an energy storage unit based on OS-TEHNG is developed. The wireless self-powered keyboard sends data 213 times after only sliding the OS-TEHNG once. Finally, OS-TEHNG is successfully demonstrated to drive a 40 mW wireless sensor node with a 1.3-inch OLED screen in continuous operation. This work represents a significant advance toward self-powered microsystems and practical power sources. [Display omitted] • A hybrid nanogenerator configuration is proposed for outstanding charging capability. • The OS-TENG achieves a current of 0.36 mA and a charge transfer of 24.4μC in a cycle. • The OS-TEHNG realizes an average power density of 352.3 W/m3 at 2 Hz. • A self-powered wireless keyboard sent data 213 times after sliding the OS-TEHNG once. • A 40 mW wireless sensor node with a 1.3" OLED works continuously powered by OS-TEHNG. [ABSTRACT FROM AUTHOR]

Abstract In principle, approval of a modified-release (MR) drug product is based on evidence from pharmacokinetic (PK) and/or pharmacodynamic studies and clinical efficacy/safety studies. The purpose of this survey is (i) to explore the number of new drug applications (NDAs) of MR drug products, approved by the FDA, employ the PK study as a bridge to already-approved immediate-release drug products without conducting their own clinical efficacy/safety studies; and (ii) to understand the type of PK studies are required for such NDAs. To this end, we surveyed the approved records of MR drug products from 2008 to 2017 from the Drug@FDA website, and filtered pertinent information from FDA's assessment reports. A total of five out of 79 products were found. A single dose PK study was conducted to investigate the underlying drug release mechanisms in four of these products. For these products, the applicants also performed multiple dose PK equivalence studies, but the PK parameters used to support the equivalence were different among studies. Information regarding the exposure-response relationship was available for all selected products, which is fundamental for such cases. Although the difference in PK curve shapes is recognized as being critical for the clinical effectiveness, this evaluation was not performed in all selected cases, as indicated in FDA's assessment reports. Highlights • A clinical efficacy/safety study is not always necessary for NDAs of MR drug products. • A PK study can replace a clinical study, but a well-defined exposure response relationship is an essential prerequisite. • Our work may provide useful insights for development of a MR drug product. [ABSTRACT FROM AUTHOR]

Wearable sensing devices play an increasingly important role in advancing the rapid development of the Internet of Things (IoT) and artificial intelligence (AI), and a smart sensing network based on wide-distributed sensing nodes has become an appealing trend. However, monolithic integration of multiple sensing functions is still a critical issue for sensing nodes. Herein, we present a flexible multifunctional sensor based on a silk fibroin/silver nanowire (SF/AgNW) composite film. Mask spray coating technology is optimized to prepare the functional sensing layer with a cross-linked AgNW network structure inside. The association of the SF/AgNW composite film and the cross-linked AgNW network structure endows the developed sensor with pressure sensing characteristics and temperature sensing characteristics. Furthermore, by in-depth analysis of the coupling law between the input variables and the resistance changes, the sensor is successfully extended to realize the functions of finger proximity detection and human breathing monitoring. Additionally, the sensor is successfully confirmed to possess remarkable mechanical reliability and sensing characteristic stability by a systematic experiment. More importantly, to highlight the practical feasibility of the proposed sensor, an all-in-one self-powered wireless multi-sensing microsystem is constructed based on the developed sensor, a high-performance triboelectric-piezoelectric-electromagnetic hybrid generator (TPEHG), and system circuits. With the TPEHG as the only power source, the microsystem is successfully demonstrated to realize continuous self-powered work and sense environmental variables through the developed sensor. Meanwhile, the obtained sensing data are transmitted to a mobile phone in real time at 1 Hz. The multiple sensing characteristics of the sensor and the autonomous features of the microsystem give them outstanding potential and value in the smart IoT field, especially in constructing a distributed smart sensing network. [Display omitted] • A high-performance hybrid nanogenerator (TPEHG) realize an output power of 8.04 mW. • A SF/AgNW-based multifunctional sensor is applied to construct a wireless microsystem. • An all-in-one completely self-powered multi-sensing microsystem is powered by TPEHG. • The microsystem can continuously sense environmental variables through SF/AgNW sensor. [ABSTRACT FROM AUTHOR]