Temporal coupling of field potentials and action potentials in the neocortex

The local field potential (LFP) is an aggregate measure of group neuronal activity and is often correlated with the action potentials of single neurons. In recent years, investigators have found that action potential firing rates increase during elevations in power high‐frequency band oscillations (50–200 Hz range). However, action potentials also contribute to the LFP signal itself, making the spike–LFP relationship complex. Here, we examine the relationship between spike rates and LFP in varying frequency bands in rat neocortical recordings. We find that 50–180 Hz oscillations correlate most consistently with high firing rates, but that other LFP bands also carry information relating to spiking, including in some cases anti‐correlations. Relatedly, we find that spiking itself and electromyographic activity contribute to LFP power in these bands. The relationship between spike rates and LFP power varies between brain states and between individual cells. Finally, we create an improved oscillation‐based predictor of action potential activity by specifically utilizing information from across the entire recorded frequency spectrum of LFP. The findings illustrate both caveats and improvements to be taken into account in attempts to infer spiking activity from LFP.We examined the relationship between spike rates and local field potentials (LFP) in the rat neocortex, and we find that while 50–180 Hz oscillatory power correlates most consistently with firing rates of neurons, other LFP bands also carry spiking‐related information. We additionally find that spiking itself and electromyographic activity contribute to LFP power and that the ratio of excitatory to inhibitory activity also correlates with 50–180 Hz power. Finally, we create an improved oscillation‐based predictor of action potential activity by utilizing information from the entire LFP frequency spectrum at once.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/1/ejn13807-sup-0001-FigS1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/2/ejn13807-sup-0007-FigS7.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/3/ejn13807-sup-0002-FigS2.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/4/ejn13807-sup-0003-FigS3.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/5/ejn13807-sup-0005-FigS5.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/6/ejn13807_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/7/ejn13807-sup-0009-reviewerComments.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/8/ejn13807-sup-0006-FigS6.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/9/ejn13807-sup-0008-FigS8.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/10/ejn13807.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146325/11/ejn13807-sup-0004-FigS4.pd

Research and Design of Indoor Parking Guidance System for Urban Traffic

In view of the existing drawbacks of indoor parking guidance system in commercial areas, this paper designs an indoor parking guidance system suitable for urban traffic. The owner first selects the appropriate parking lot through the Mini Program, and reserves a detailed parking space on the Mini Program, and after arriving at the parking lot, the Mini Program performs optimal path planning according algorithm to guide the owner to find the parking space. After arriving at the reserved parking space according to the prompts, the smart parking lock is unlocked by "one-key unlock", and the video detection system observes the parking behavior in real time to avoid the occurrence of illegal parking. At the same time, voice assistants and blind spot guidance facilities are also provided during the induction process to optimize the urban parking guidance system

Divide and Conquer Partition for Fourier Reconstruction Sparse Inversion with its Applications

A partition method, with an efficient divide and conquer partition strategy, for the non-uniform sampling signal reconstruction based on Fourier reconstruction sparse inversion (FRSI) is developed. The novel partition FRSI(P-FRSI) is motivated by the observation that the partition processing of multi-dimensional signals can reduce the reconstruction difficulty and save the reconstruction time. Moreover, it is helpful to choose suitable reconstruction parameters. The P-FRSI employs divide and conquer strategy, and the signal is firstly partitioned into some blocks. Following that, traditional FRSI is applied to reconstruct signals in each block. We adopt linear or nonlinear superposition to determine the weight coefficients during integrating these blocks. Finally, P-FRSI is applied to two-dimensional seismic signal reconstruction. The superiority of the new method over conventional FRSI is demonstrated by numerical reconstruction experiments

Molecular Characterization of Anaplasma , Ehrlichia, Babesia , and Borrelia in Ticks from Guangdong Province of Southern China

Tick-borne pathogens have become emerging global health threats in humans and animals. The objective of the present study was to investigate Anaplasma, Ehrlichia, Babesia , and Borrelia in ticks in southern China. Ticks were collected from animals and identified to the species level. Tick-borne Anaplasma , Ehrlichia , Babesia , and Borrelia were tested by PCR assays, and analyzed by sequencing and phylogenetics. We collected 747 ticks, including Rhipicephalus microplus (n=225) and R. sanguineus (n=522), from pet dogs in Guangdong Province of southern China. Using PCR and phylogenetic analysis we showed that these ticks carried Anaplasma platys , Ehrlichia canis , Borrelia miyamotoi , Babesia vogeli , and an unclassified Ehrlichia species in Rhipicephalus ticks. Of these pathogens, B. miyamotoi was first found in southern China. A. platys , E. canis , and B. miyamotoi were zoonotic pathogens that infected both R. microplus and R. sanguineus , whereas Ba. vogeli only infected R. sanguineus , with a prevalence of 0.3%-1.5%. The results of this study showed diversity and complexity of tick-borne pathogens in Guangdong Province of southern China, implying the importance of tick-borne pathogen surveillance and control

A Novel Indolium-Based Fluorescent Probe for Fast Detection of Cyanide

A novel indolium-based fluorescent probe for the detection of CN− was developed based on the conjugation of 1, 2, 3, 3-Tetramethyl-3H-indolium iodide and 2-acetyl benzothiophene. The introduction of external CN− caused a nucleophilic attack to the quaternary amine salt structure in the probe and resulted in the departure of iodide ions and the steric rotation of the index salt group, which caused fluorescence quenching. The titration experiments showed that the probe had rapid qualitative and quantitative analysis capabilities for CN−. Moreover, the relevant biocompatibility experiments also demonstrated the potential application value of the probe

Curcumin Suppresses Proliferation and Migration of MDA-MB-231 Breast Cancer Cells through Autophagy-Dependent Akt Degradation.

Previous studies have evidenced that the anticancer potential of curcumin (diferuloylmethane), a main yellow bioactive compound from plant turmeric was mediated by interfering with PI3K/Akt signaling. However, the underlying molecular mechanism is still poorly understood. This study experimentally revealed that curcumin treatment reduced Akt protein expression in a dose- and time-dependent manner in MDA-MB-231 breast cancer cells, along with an activation of autophagy and suppression of ubiquitin-proteasome system (UPS) function. The curcumin-reduced Akt expression, cell proliferation, and migration were prevented by genetic and pharmacological inhibition of autophagy but not by UPS inhibition. Additionally, inactivation of AMPK by its specific inhibitor compound C or by target shRNA-mediated silencing attenuated curcumin-activated autophagy. Thus, these results indicate that curcumin-stimulated AMPK activity induces activation of the autophagy-lysosomal protein degradation pathway leading to Akt degradation and the subsequent suppression of proliferation and migration in breast cancer cell

Targeting of N-Type Calcium Channels via GABAB-Receptor Activation by α-Conotoxin Vc1.1 Variants Displaying Improved Analgesic Activity

α-Conotoxins exhibiting analgesic activity, such as Vc1.1, have been shown to inhibit α9α10 nicotinic acetylcholine receptors (nAChRs) and GABAB-receptor (GABABR) coupled N-type (CaV2.2) calcium channels. Here, we report two Vc1.1 variants, Vc1.1[N9R] and benzoyl-Vc1.1[N9R], that selectively inhibit CaV2.2 channels via GABABR activation but exhibit reduced inhibitory activity at α9α10 and other neuronal nAChR subtypes compared with Vc1.1. Surprisingly, the analgesic activity of Vc1.1[N9R] and benzoyl-Vc1.1[N9R] was more potent than that of Vc1.1 when tested in partial sciatic nerve ligation injury and chronic constriction injury models. Vc1.1[N9R] and benzoyl-Vc1.1[N9R] exhibited either similar or tenfold higher activity of GABABR-mediated CaV2.2 inhibition but no activity at CaV2.2 alone; however, the mechanism of increased analgesic activity is unknown. The effects on analgesic activity and α9α10 nAChR of other Vc1.1 variations at position 9 and the N-terminus were also determined. Our findings provide new insights for designing potent inhibitors for GABABR-coupled N-type (CaV2.2) calcium channels