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Objective To establish a set of single nucleotide polymorphisms (SNP) detection protocol for inbred rats based on multiplex PCR-ligase detection reaction (LDR).Methods A total of 40 rats SNP sites were selected on chromosomes 1-20 and X of rats among 5 inbred strains of rats, and the 40 SNP sites were randomly divided into four groups. A genetic detection protocol for 4 groups of SNP in inbred rats based on multiplex PCR-LDR technology was constructed. 9 commonly used rat strains from two other domestic rat suppliers were detected by this protocol. Finally, the feasibility of this protocol was verified by comparing the amplification effects of different DNA polymerases by a third-party laboratory.Results When using the constructed SNP detection protocol for inbred rats to test 5 rat strains, all sites in each sample obtained good amplification results. The 9 commonly used rat strains from two other rat suppliers in china were also well amplified by this SNP detection protocol, and 40 SNPs were homozygous in each Inbred strain. The results of detection of the same rat DNA samples with three different DNA polymerases showed that the Multiplex PCR Kit, AmpliTaq Gold 360 DNA polymerase and Platinum II Taq hot start DNA polymerase had electrophoretic peaks of amplification products at all SNP sites in groups 1 to 3, and Platinum II Taq hot start DNA polymerase had one less electrophoretic peak of the amplification products at the SNP sites in group 4. In addition, inter-laboratory comparisons showed consistent results for the same amplification system.Conclusion Based on multiplex PCR-LDR technology, this study successfully established a SNP detection protocol for rats covering all autosomes and X chromosomes with the excellent stability and repeatability.

Tooth break is a common fault which always occurs in the planetary gearboxes, and when it occurs, due to the influence of transmission path, the vibration signal collected by the sensor becomes complicated, which brings difficulties to fault diagnosis. Thus, in order to study the influence of transmission path on spectrum structure of planetary gearboxes with tooth break fault, the rigid-flexible coupling models with no fault, sun gear tooth break fault, planet gear tooth break fault and ring gear tooth break fault of planetary gearboxes are established on Adams, and the vibration signals of the box body are extracted and analyzed by simulation. The simulation results show that: in the time-domain, the change of the path will have an obvious amplitude modulation on the vibration signal which is measured at a fixed point of the box. What's more, in the spectrum diagram, the two sides of the meshing frequency will also produce side bands composed of different frequencies.This study can provide basis and reference for fault diagnosis of planetary gearboxes in the future.

Recent advancements in neural probe technology have become pivotal in both neuroscience research and the clinical management of neurological disorders. State-of-the-art developments have led to the advent of multichannel, high-density bidirectional neural interfaces that are adept at both recording and modulating neuronal activity within the central nervous system. Despite this progress, extant bidirectional probes designed for simultaneous recording and stimulation are beset with limitations, including elicitation of inflammatory responses and insufficient charge injection capacity. In this paper, we delineate the design and application of an innovative ultraflexible bidirectional neural probe engineered from polyimide. This probe is distinguished by its ability to facilitate high-resolution recordings and precise stimulation control in deep brain regions. Electrodes enhanced with a PEDOT:PSS/IrOx composite exhibit a substantial increase in charge storage capacity, escalating from 0.14 ± 0.01 mC/cm2 to an impressive 24.75 ± 0.18 mC/cm2. This augmentation significantly bolsters the electrodes' charge transfer efficacy. In tandem, we observed a notable reduction in electrode impedance, from 3.47 ± 1.77 MΩ to a mere 41.88 ± 4.04 kΩ, while the phase angle exhibited a positive shift from −72.61 ± 1.84° to −34.17 ± 0.42°. To substantiate the electrodes' functional prowess, we conducted in vivo experiments, where the probes were surgically implanted into the bilateral motor cortex of mice. These experiments involved the synchronous recording and meticulous analysis of neural signal fluctuations during stimulation and an assessment of the probes' proficiency in modulating directional turning behaviors in the subjects. The empirical evidence corroborates that targeted stimulation within the bilateral motor cortex of mice can modulate the intensity of neural signals in the stimulated locale, enabling the directional control of the mice's turning behavior to the contralateral side of the stimulation site. [ABSTRACT FROM AUTHOR]

A 3-dimensional carbonized multi-walled carbon nanotube (MWCNT) paper was used as the host of nano-tin oxide (SnO2) for lithium-ion batteries (LIBs). The cellulose fibers were fully mixed with MWCNTs in water. Then, the paper was obtained via vacuum filtration. Carbonization was carried out in a vacuum furnace at 1460°C. SnO2 slurry was coated on the carbonized MWCNT paper (CMP). Scanning electron microscopy (SEM) was utilized to observe the anode electrode. The images of SEM indicated that the nano-SnO2 was embedded into the holes of the porous CMP collector. This contributed the increase of contact interface area of the nano-SnO2 and the collector and the significantly reduced interface resistance. Electrochemical tests showed that the initial discharge capacity reached 1745 mAh g−1 with a coulumbic efficiency (CE) of 70.39% at a current density of 50 mA g−1. The composite electrode still maintained a reversible capacity of 753 mAh g−1 with a CE of 98% at a current density of 200 mA g−1 after 100 cycles. These marvelous composite electrodes exhibited a promising future for the next generation of LIBs. [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes have been synthesized by floating reactant method in a vertical tubular reactor. An internal short approach process was developed to achieve the pre-lithiated multiwalled carbon nanotube MWCNTs/graphite composite anodes. Lithium-ion capacitors (LICs) were composed of a pre-lithiated multiwalled carbon nanotubes/graphite composite anode and an activated carbon (AC) cathode. The electrochemical performance of LICs with different MWCNTs content was investigated through galvanostatic charge/discharge and electrochemical impedance. The results show that the charge-discharge performance of LICs was greatly improved with the addition of MWCNTs in anodes. LIC25 (25 wt% MWCNTs) was found to achieve the optimal electrochemical performance. The LIC25 hold a specific capacitance of 58.2 F/g at the current density of 100 mA/g. The maximum energy density and power density were up to 96 Wh/kg and 10.1 kW/kg, respectively, in the current range of 100~8000 mA/g. The continuous galvanostatic charge-discharge cycling tests revealed that the LIC25 maintained excellent capacity retention of 86% after 3000 cycles. [ABSTRACT FROM AUTHOR]

Unlike thermoplastic petroleum-based materials, starch-based materials rely on aqueous systems but are incapable of hot melting, resulting in low processing efficiency and limited large-scale industrial applications. In this study, the combination of α-amylase liquefaction and urea plasticization was used for the first time to obtain enzymatic thermoplastic starch (ETPS) for hot melting by changing the molecular chain of starch. ETPS showed an apparent hot melting phenomenon when heated below 200 °C. Differential scanning calorimetry revealed that heat absorption peaks were obviously reduced, and the hot melting phenomenon occurred easily depending on the combination of enzymatic hydrolysis and plasticization. Dynamic mechanical analysis indicated that the combined modification effectively increased the number of freely movable chains. The red shift of -OH stretching vibration peaks indicated the formation of strengthened hydrogen bonds in ETPS. X-ray diffraction showed that the crystallinity of ETPS was reduced to 5.68 %, effectively reducing the regenerative phenomenon. Gel permeation chromatography revealed that the molecular weight of ETPS decreased, and the entanglements between molecular chains were reduced. A tensile test showed that the elongation at break of ETPS was as high as 235.29 %, which was much higher than those of enzymatic hydrolysis starch and thermoplastic starch. [Display omitted] [ABSTRACT FROM AUTHOR]