Structure Studies on Host-Guest Recognition Sensory Systems

Rhodamine B-ethylenediamine-beta-cyclodextrins (RhB-beta-CDen) and rhodamine B-beta-cyclodextrins (RhB-beta-CD) form inclusion complexes with many guest molecules, which can be used as nucleic acid probe. In this paper we determined the most stable conformations of RhB-beta-CDen and RhB-beta-CD by molecular mechanics and dynamics simulation. The interaction between RhB-beta-CDen and two guest molecules, 1-borneol and cyclohexanol, have been investigated both theoretically and experimentally. The results show that the interaction between borneol and RhB-beta-CDen is stronger than that between cyclohexanol and RhB-beta-CDen.

Recent advances in fabrication and functions of neuromorphic system based on organic field effect transistor

The development of various artificial electronics and machines would explosively increase the amount of information and data,which need to be processed via in-situ remediation.Bioinspired synapse devices can store and process signals in a parallel way,thus improving fault tolerance and decreasing the power consumption of artificial systems.The organic field effect transistor(OFET)is a promising component for bioinspired neuromorphic systems because it is suitable for large-scale integrated circuits and flexible devices.In this review,the organic semiconductor materials,structures and fabrication,and different artificial sensory perception systems functions based on neuromorphic OFET devices are summarized.Subsequently,a summary and challenges of neuromorphic OFET devices are provided.This review presents a detailed introduction to the recent progress of neuromorphic OFET devices from semiconductor materials to perception systems,which would serve as a reference for the development of neuromorphic systems in future bioinspired electronics.

The Bionic Anticipation of Natural Disasters

After major natural disasters, such as the recent earthquake-tsunami event in South Asia, reports appear about the mysterious ability of animals to anticipate and to escape the impending danger. This is an opportunity to recall the long history of this phenomenon in the traditions of different civilizations, to evaluate Chinese efforts, 30-40 years ago, to use this phenomenon for earthquake prediction, and to judge its state of acceptance in modem science. An effort is made to introduce this phenomenon as a research field of modem bionics. The timing is favorable since, increasingly, infrared thermal anomalies, monitored from satellite, suggesting litho-atmospheric processes, are found to precede earthquakes. They were unexpected by seismologists and are here suggested to essentially reflect the energy conversion patterns responsible for the signals monitored by animals. The aim is to learn from animals in the long term how natural disasters can better be anticipated, and how simple technical warning systems can be developed. Some challenges are analyzed. One is interpretation of the nature of energy release prior to the main earthquake disaster resulting in ＂macro-anomaly＂ precursors, another is better to understand the effect on animal senses. The role of non-linear cooperative phenomena including tsunamitype waves is emphasized.

A hybrid flexible gas sensory system with perceptual learning

Imbuing artificial sensory system with intelligence of the biological counterpart is limited by challenges in emulating perceptual learning ability at the device level.In biological systems,stimuli from the surrounding environment are detected,transmitted,and processed by receptor,afferent nerve,and brain,respectively.This process allows the living creatures to identify the potential hazards and improve their adaptability in various environments.Here,inspired by the biological olfaction system,a gas sensory system with perceptual learning is developed.As a proof-of-concept,H2S gas with various concentrations is used as the stimulation and the stimuli will be converted to pulse-like physiological signals in the designed system,which consists of a gas sensor,a flexible oscillator,and a memristor-type artificial synapse.Furthermore,the learning ability is implemented using a supervised learning method based on k-nearest neighbors(KNN)algorithm.The recognition accuracy can be enhanced by repeating training,illustrating a great potential to be used as the neuromorphic sensory system with a learning ability for the applications in robotics.

Do human activities influence survival and orientation abilities of larval fishes in the ocean?

The larval stages of most marine fishes spend days to weeks in the pelagic environment,where they must find food and avoid predators in order to survive.Some fish only spend part of their life history in the pelagic environment before returning to their adult habitat,for example,a coral reef.The sensory systems of larval fish develop rapidly during the first few days of their lives,and here we concentrate on the various sensory cues the fish have available to them for survival in the pelagic environment.We focus on the larvae of reef fishes because most is known about them.We also review the major threats caused by human activities that have been identified to have worldwide impact and evaluate how these threats may impact larval-fish survival and orientation abilities.Many human activities negatively affect larval-fish sensory systems or the cues the fish need to detect.Ultimately,this could lead to decreased numbers of larvae surviving to settlement,and,therefore,to decreased abundance of adult fishes.Although we focus on species wherein the larvae and adults occupy different habitats(pelagic and demersal,respectively),it is important to acknowledge that the potential anthropogenic effects we identify may also apply to larvae of species like tuna and herring,where both larvae and adults are pelagic.