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Integrative neural interfaces combining neurophysiology and optogenetics with neural imaging provide numerous opportunities for neuroscientists to study the structure and function of neural circuits in the brain. Such a comprehensive interface demands miniature electrode arrays with high transparency, mechanical flexibility, electrical conductivity, and biocompatibility. Conventional transparent microelectrodes made of a single material, such as indium tin oxide (ITO), ultrathin metals, graphene and poly-(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS), hardly possess the desired combination of those properties. Herein, ultra-flexible, highly conductive and fully transparent microscale electrocorticogram (μECoG) electrode arrays made of a PEDOT:PSS–ITO–Ag–ITO assembly are constructed on thin parylene C films. The PEDOT:PSS–ITO–Ag–ITO assembly achieves a maximum ∼14% enhancement in light transmission over a broad spectrum (350–650 nm), a significant reduction in electrochemical impedance by 91.25%, and an increase in charge storage capacitance by 1229.78 μC cm−2. Peeling, bending, and Young's modulus tests verify the enhanced mechanical flexibility and robustness of the multilayer assembly. The μECoG electrodes enable electrical recordings with high signal-to-noise ratios (SNRs) (∼35–36 dB) under different color photostimulations, suggesting that the electrodes are resilient to photon-induced artifacts. In vivo animal experiments confirm that our array can successfully record light-evoked ECoG oscillations from the primary visual cortex (V1) of an anesthetized rat. [ABSTRACT FROM AUTHOR]

We created a novel laminar-flow based microbial fuel cell (MFC) array to be an integrable and scalable power source for portable lab-on-a-chip (LOC) devices. The microfluidic MFC enabled the laminar flow of anolyte and catholyte streams in a microchannel without any physical membranes while the device harvested electricity by utilizing ion transfers through the laminar interface which acts as a virtual membrane. The array prototype incorporated four series-connected fuel cells and was operated with two common inlets for the continuous introduction of the anolyte and catholyte. In the anodic flow region, microorganisms oxidized organic media and completed respiration by transferring the electrons to the anodes. The protons generated by the anodic reactions passed through the liquid-liquid interfaces and traveled to the cathodic streams. The electrons then moved across the external resistors to the cathodes where they combined with the protons and reduced oxidant (i.e. catholyte). The array generated a maximum power output of 60.5 μW/cm 2 using a 100 kΩ load, which outperformed a single laminar flow MFC unit by a factor of approximately 4. The series or parallel application of this array structure, using microfluidic MFCs integrated into a single LOC device, can offer the potential for on-chip power generation. [ABSTRACT FROM AUTHOR]

The fracture behaviors near the mode II interface crack tip for orthotropic bimaterial are studied. The non-oscillatory field, where the stress singularity exponent is a real number, is discussed by the complex function method and the undetermined coefficient method. From the research fracture problems, the stress functions with ten undetermined coefficients and an unknown singularity exponent are introduced when Δ > 0 and Δ > 0. By the existence theorem of non-trival solutions for the system of eight homogeneous linear equations, the characteristic equation, the stress singularity exponent, and the discriminating condition of the non-oscillatory singularity are found. By the uniqueness theorem of the solutions for the system of twelve non-homogeneous linear equations with ten unknowns, the ten undermined coefficients in the stress functions are uniquely determined. The definitions of the stress intensity factors are given with the help of one-sided limit, and their theoretical formulae are deduced. The analytic solutions of the stresses near the mode II interface crack tip are derived. The classical results for orthotropic material are obtained. [ABSTRACT FROM AUTHOR]

This work describes the development and operation of a microliter-sized microbial fuel cell-based biosensor for monitoring toxic substances in water. The biosensor features the integration of (i) a three-electrode configuration to provide electrochemical sensing functionality for improving sensitivity and reliability in water quality testing and (ii) an air-bubble trap to prevent all unwanted bubbles from entering the sensing surface for maximizing bacterial growth and their subsequent electron transfer. The miniaturization of the biosensor produced favorable conditions for (i) reducing measurement time with high probability of cell attachment/biofilm formation in the micro-sized chamber and (ii) enhancing the reaction sensitivity with large surface area-to-volume ratio and increased reaction kinetics. When formaldehyde was introduced as a toxic component, the rapid and sensitive current responses were obtained over a concentration range from 0.001% to 0.1% in the biosensor with 0.2 V (versus solid-state thin film Ag/AgCl reference electrode) applied on the anode. [ABSTRACT FROM AUTHOR]

Droplet microfluidics is a highly sensitive and high-throughput technology extensively utilized in biomedical applications, such as single-cell sequencing and cell screening. However, its performance is highly influenced by the droplet size and single-cell encapsulation rate (following random distribution), thereby creating an urgent need for quality control. Machine learning has the potential to revolutionize droplet microfluidics, but it requires tedious pixel-level annotation for network training. This paper investigates the application software of the weakly supervised cell-counting network (WSCApp) for video recognition of microdroplets. We demonstrated its real-time performance in video processing of microfluidic droplets and further identified the locations of droplets and encapsulated cells. We verified our methods on droplets encapsulating six types of cells/beads, which were collected from various microfluidic structures. Quantitative experimental results showed that our approach can not only accurately distinguish droplet encapsulations (micro-F1 score > 0.94), but also locate each cell without any supervised location information. Furthermore, fine-tuning transfer learning on the pre-trained model also significantly reduced (>80%) annotation. This software provides a user-friendly and assistive annotation platform for the quantitative assessment of cell-encapsulating microfluidic droplets. [ABSTRACT FROM AUTHOR]

In this paper, mechanics analysis for crack tip fields of linear elastic orthotropic composite plate under symmetric bending load was done. By using a complex variable method, the equations for bending moment, twisting moment, stress, strain and displacement fields near crack tip are derived. [ABSTRACT FROM AUTHOR]

With the completion of the poverty alleviation task in China, the Chinese economy has made great breakthroughs. Meanwhile, the implementation of Chinese "dual carbon" goal has entered an important window period of both strategic opportunities and difficulties. The emission of carbon dioxide (CO2) leads to the greenhouse effect, which affects the sustainable development of society. Therefore, this paper proposes an improved analytic hierarchy process (AHP) with Slacks-based measure integrating data envelopment analysis (SBMDEA) (AHP-SBMDEA) based efficiency evaluation model for different provincial-level administrative regions in China, which is used to analyze and optimize the Chinese energy structure of different provincial-level administrative regions. With coal, gasoline, petroleum, fuel oil, diesel, crude oil and natural gas as inputs, the per capita Gross Domestic Product (GDP) as the desired output and the CO2 as the undesired output, after linear weighted calculation of the results of the AHP-SP model and the SBMDEA model, the energy efficiency evaluation model of different provincial administrative regions in China is established. The results show that there is a large difference in efficiency between Chinese northern and southern regions, and the overall efficiency of southern regions is higher than that of northern regions. In addition, it is easier to find out the optimal energy efficiency benchmark, which can provide suggestions and help to guide the energy consumption input structure improvement of other inefficient provincial-level administrative regions. Furthermore, the energy structure can also be adjusted through the redundant variable calculated by the SBMDEA model. For example, Sichuan Province can reduce the consumption of the coal, the gasoline, the diesel, the fuel oil, the crude oil and the natural gas by 5269.95 × 10000 tons (WT), 513.01 WT, 59.05 WT, 34.37 WT, 4,73.33 WT and 130.37 billion cubic meters (BCM), respectively. Its CO2 emissions can be reduced by 1925.4 WT, and raise the efficiency of energy utilization in the province. [Display omitted] • Novel economy and CO 2 emissions evolution model based on a AHP-SBMDEA is proposed. • The proposed model can identify the optimal energy efficiency benchmark. • GDP per capita can be increased and CO 2 emissions can be decreased. [ABSTRACT FROM AUTHOR]

The effects of impulse noise (firecrackers at 170 dB SPL, 1, 10, 20 rounds) on auditory cortical response threshold (CRT) and activity of succinic dehydrogenase (SDH) and acetylcholinesterase (AchE) in the inner ear were studied in 37 guinea pigs. The results showed that extent of damage in the cochlea was related to amount of exposure to the noise. Exposure to 10 rounds resulted in temporal threshold shift (TTS); to 20 rounds the result was permanent threshold shift (PTS). For the period when TTS existed, inverse correlation was noticed between enzyme activity change and CRT shift. The correlation could not be established when PTS was induced. The results suggest that the pathomechanism of PTS was more complex than that of TTS. The significance of the results is discussed. [ABSTRACT FROM AUTHOR]