13 research outputs found
When moles became diggers: Tegulariscaptor
The systematics of Geotrypus is among the most debated within Talpidae, but the recent development of quantitative methods for shape analyses allows us to provide a thorough reconsideration of Geotrypus spp. In the present study, we perform a systematic revision of the species Geotrypus minor from the early Oligocene of Germany using two-dimensional geometric morphometrics on the humerus, and cladistic analyses using two different character matrices. Our results suggest a distinct generic allocation for this species based on its unique humeral shape. Cladistic analyses reveal that G. minor has closer phylogenetic relationships with urotrichine shrew-moles than with other Geotrypus species or highly fossorial moles. Quantitative methods applied in this study support qualitative observations and fully justify a new generic allocation. In light of these results, Tegulariscaptor gen. nov. is proposed to encompass the material previously assigned to G. minor
Properties and application of a multichannel integrated circuit for low-artifact, patterned electrical stimulation of neural tissue
Modern multielectrode array (MEA) systems can record the neuronal activity from thousands of electrodes, but their ability to provide spatio-temporal patterns of electrical stimulation is very limited. Furthermore, the stimulus-related artifacts significantly limit the ability to record the neuronal responses to the stimulation. To address these issues, we designed a multichannel integrated circuit for a patterned MEA-based electrical stimulation and evaluated its performance in experiments with isolated mouse and rat retina. The Stimchip includes 64 independent stimulation channels. Each channel comprises an internal digital-to-analogue converter that can be configured as a current or voltage source. The shape of the stimulation waveform is defined independently for each channel by the real-time data stream. In addition, each channel is equipped with circuitry for reduction of the stimulus artifact. Main results. Using a high-density MEA stimulation/recording system, we effectively stimulated individual retinal ganglion cells (RGCs) and recorded the neuronal responses with minimal distortion, even on the stimulating electrodes. We independently stimulated a population of RGCs in rat retina, and using a complex spatio-temporal pattern of electrical stimulation pulses, we replicated visually evoked spiking activity of a subset of these cells with high fidelity. Significance. Compared with current state-of-the-art MEA systems, the Stimchip is able to stimulate neuronal cells with much more complex sequences of electrical pulses and with significantly reduced artifacts. This opens up new possibilities for studies of neuronal responses to electrical stimulation, both in the context of neuroscience research and in the development of neuroprosthetic devices
Roadmap on artificial intelligence and big data techniques for superconductivity
AbstractThis paper presents a roadmap to the application of AI techniques and big data (BD) for different modelling, design, monitoring, manufacturing and operation purposes of different superconducting applications. To help superconductivity researchers, engineers, and manufacturers understand the viability of using AI and BD techniques as future solutions for challenges in superconductivity, a series of short articles are presented to outline some of the potential applications and solutions. These potential futuristic routes and their materials/technologies are considered for a 10–20 yr time-frame.</jats:p