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101.
102.
Caifang Gao Mu-Pai Lee Mengjiao Li Ko-Chun Lee Feng-Shou Yang Che-Yi Lin Kenji Watanabe Takashi Taniguchi Po-Wen Chiu Chen-Hsin Lien Wen-Wei Wu Shu-Ping Lin Wenwu Li Yen-Fu Lin Junhao Chu 《Advanced functional materials》2021,31(5):2005182
The human brain is often likened to an incredibly complex and intricate computer, rather than electrical devices, consisting of billions of neuronal cells connected by synapses. Different brain circuits are responsible for coordinating and performing specific functions. The reward pathway of the synaptic plasticity in the brain is strongly related to the features of both drug addiction and relief. In the current study, a synaptic device based on layered hafnium disulfide (HfS2) is developed for the first time, to emulate the behavioral mechanisms of drug dosage modulation for neuroplasticity. A strong gate-dependent persistent photocurrent is observed, arising from the modulation of substrate-trapping events. By controlling the polarity of gate voltage, the basic functions of biological synapses are realized under a range of light spiking conditions. Furthermore, under the control of detrapping/trapping events at the HfS2/SiO2 interface, positive/negative correlations of the An/A1 index, which significantly reflected the weight change of synaptic plasticity, are realized under the same stimulation conditions for the emulation of the drug-related addition/relief behaviors in the brain. The findings provide a new advance for mimicking human brain plasticity. 相似文献
103.
Mengjiao Li Feng-Shou Yang Hung-Chang Hsu Wan-Hsin Chen Chia Nung Kuo Jiann-Yeu Chen Shao-Heng Yang Ting-Hsun Yang Che-Yi Lin Yi Chou Mu-Pai Lee Yuan-Ming Chang Yung-Cheng Yang Ko-Chun Lee Yi-Chia Chou Chen-Hsin Lien Chun-Liang Lin Ya-Ping Chiu Chin Shan Lue Shu-Ping Lin Yen-Fu Lin 《Advanced functional materials》2021,31(5):2007587
Defect engineering represents a significant approach for atomically thick 2D semiconductor material development to explore the unique material properties and functions. Doping-induced conversion of conductive polarity is particularly beneficial for optimizing the integration of layered electronics. Here, controllable doping behavior in palladium diselenide (PdSe2) transistor is demonstrated by manipulating its adatom-vacancy groups. The underlying mechanisms, which originate from reversible adsorption/desorption of oxygen clusters near selenide vacancy defects, are investigated systematically via their dynamic charge transfer characteristics and scanning tunneling microscope analysis. The modulated doping effect allows the PdSe2 transistor to emulate the essential characteristics of photo nociceptor on a device level, including firing signal threshold and sensitization. Interestingly, electrostatic gating, acting as a neuromodulator, can regulate the adaptive modes in nociceptor to improve its adaptability and perceptibility to handle different danger levels. An integrated artificial nociceptor array is also designed to execute unique image processing functions, which suggests a new perspective for extension of the promise of defect engineered 2D electronics in simplified sensory systems toward use in advanced humanoid robots and artificial visual sensors. 相似文献
104.
Flora W Y Chiu Hakan Bagci Amanda G Fisher Andrew J deMello Katherine S Elvira 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2016,91(1):16-24
Cellular fusion is a key process in many fields ranging from historical gene mapping studies and monoclonal antibody production, through to cell reprogramming. Traditional methodologies for cell fusion rely on the random pairing of different cell types and generally result in low and variable fusion efficiencies. These approaches become particularly limiting where substantial numbers of bespoke one‐to‐one fusions are required, for example, for in‐depth studies of nuclear reprogramming mechanisms. In recent years, microfluidic technologies have proven valuable in creating platforms where the manipulation of single cells is highly efficient, rapid and controllable. These technologies also allow the integration of different experimental steps and characterisation processes into a single platform. Although the application of microfluidic methodologies to cell fusion studies is promising, current technologies that rely on static trapping are limited both in terms of the overall number of fused cells produced and their experimental accessibility. Here we review some of the most exciting breakthroughs in core microfluidic technologies that will allow the creation of integrated platforms for controlled cell fusion at high throughput. © 2015 Society of Chemical Industry 相似文献
105.
Kuo-Hsiung Tseng Juei-Long Chiu Heng-Lin Lee Yi-Syuan Kao Der-Chi Tien 《Materials and Manufacturing Processes》2016,31(2):186-193
This study developed a system monitoring the electric discharge machine's (EDM) discharge energy and success rate to replace conventional oscilloscope observation. By using logic circuit, the signals are transmitted to the PC monitoring platform in order to display the discharge success times, discharge success rate, and electrode's consumption energy. The advantage of the proposed system is the capability to observe real-time discharges and record the experimental conditions, as well as optimize the discharge parameter settings. The experimental results suggest that, in the preparation of nanosilver colloid, the cost-performance of Ton–Toff at 10–100 µs is the optimal setting. The monitoring system also can take advantage of the discharge success rate to control the energy consumption of the electrode to obtain the standardization of products. The results suggest that, while discharge success rate, electrode's weight loss and wavelength of the absorption peak are considerably accurate, but concentration accuracy is relatively poor. The discharge success rate monitoring system is an innovative method that can help to realize electric discharge processing, optimize product quality, and it may be a powerful processing tool in the future. 相似文献
106.
107.
In recent decades India has achieved one of the fastest economic growth rates in the world, yet its progress against both
child and adult undernutrition has been sluggish at best. While this Indian variant of the so-called Asian enigma presents
many puzzles, one of the puzzles pertains to agriculture’s role. Many researchers and policymakers have high expectations
of agriculture’s potential to reduce undernutrition, despite a lack of substantive evidence. In this paper we assess this
tenuous evidence base by exploring two key channels by which agricultural production conditions can influence nutritional
outomes: a food consumption pathway and a maternal employment–time use pathway. We conclude with an appraisal of some possible
entry points for pro-nutrition agricultural policies. 相似文献
108.
Abstract This work considers the application of Wilson and NRTL equations in the multicomponent VLE prediction. We emphasize the critical comparison of partially miscible solution treatment by these two equations. Results revealed NRTL equation performed slightly better than the Wilson equation in data credibility so far as the systems examined are concerned. Estimation of optimum NRTL parameters requires further exploration. Optimization methods of pattern search, gradient search and golden section were employed in this study. All of the computations were performed on an IBM 1130 digital computer. 相似文献
109.
A theoretical framework, accounting for high-order surface stress, is implemented in a continuum mechanics model based on the Euler-Bernoulli theory of beams and columns to simulate the buckling and resonance behavior of nanowires (NWs). Closed-form expressions for the critical buckling load of uniaxial compression of NWs are derived for different types of end conditions. Size-dependent overall Young’s modulus is characterized versus the diameter of the NWs and is compared with the experimental data. The resonance frequency of NWs is also studied and compared with the simulation results based on nonlinear, finite deformation kinematics. We demonstrate that the present prediction considering both surface moment and surface stress agrees well with the experimental data, while the pure surface stress model may not be able to capture the general trend when the NW’s diameter is less than a certain size. We conclude that the present continuum mechanics approach, considering both high-order surface effects, could be served as one of the feasible tools to analyze the mechanical behavior of nanostructures. 相似文献
110.