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In order to investigate the influence of the deflector layout on the performance of mine-used main fan diffuser, the RNG k-ε turbulence model was applied to numerical simulation of the internal flow fields under three inlet velocity conditions with and without deflector. The influence of the central angle and starting angle of the deflector on the performance of the diffuser was investigated. The results show that for the diffuser without deflector, a serious flow accumulation phenomenon exists inside the flow field, which restricts the performance improvement of the diffuser; when the center angle of the deflector is small, the larger the starting angle of its installation is, the higher the diffusion efficiency of the diffuser under the three inlet velocities considered, however the secondary flow due to the uneven pressure on the upper and lower sides of the deflector head appears at some starting angles, which results in an increase in flow losses. As the center angle of the deflector increases, the flow accumulation inside the diffuser improves gradually, and the secondary flow also gradually weakens. When the center angle reaches 60°, the diffusion efficiency is the highest.

This paper presents a low-distortion and low-power multi-stage noise-shaping (MASH) architecture Sigma-Delta (Σ Δ) modulator with double-sampling. The modulator uses a cascade of integrator feed-forward (CIFF) structure as a cascaded modulator in a MASH architecture. Since the CIFF structure provides a feedforward path from the input signal to the quantizer, the input signal is directly transmitted to the output without loop processing, relaxing the linearity requirement of the modulator, reducing performance requirements for the OTA and harmonic distortion. Double-sampling technique is adopted in the first integrator to double the sampling rate, improving the accuracy of the modulator without the increase of power consumption. In order to eliminate the influence of capacitor mismatch in the sampling network, a fully floating differential switched capacitor (SC) feedback digital-to-analog (DAC) is used in the integrator. The simulation results show that the Σ Δ modulator achieves 113 dB signal-to-noise and distortion ratio (SNDR) and the power consumption is 3.15 mW from a 5 V power supply. [ABSTRACT FROM AUTHOR]

Micro/mini‐light emitting diode (LED) arrays are regarded as the most promising next generation of display devices. However, the inherent Lambertian radiation of LED chips results in a significant pixel crosstalk. To improve the display quality, high‐quality micro/mini‐LED display pixels with fully enclosed composite micro/nano‐packages and in situ nanoimprint technology are proposed and demonstrated in this work. The nanoimprint template is designed as a composite structure comprising an intermediate sandwich cavity array and thin‐bottom nanostructure layer. Contact is maintained between the template and LED chips array substrate. By vacuuming the sealed sandwich cavities, the thin‐bottom nanostructure layer is deformed to drive the upward protrusion of the liquid optical polymer. Moreover, the nanocavities on the thin nanostructure layer are fully filled by the polymer, forming a composite micro/nano‐package. The characteristics of the composite micro/nano‐package, such as the aperture and protrusion height, can be flexibly adjusted by changing the template structure or process parameters. A 6 × 8 array LED chips display device enclosed by a composite micro/nanopackage is developed. The divergence angle of the single LED chip decreases to 72° from the original 138°, the light‐extraction efficiency increases18.4%, and the luminescence spectrum and current‐voltage characteristics changes only minimally. [ABSTRACT FROM AUTHOR]

An efficient method for the construction of 2‐methyl‐1‐sulfonylindoles and 2,3‐dimethyl‐1‐sulfonylindoles using solid calcium carbide as an alkyne source and o‐sulfonamidobenzaldehyde hydrazones or o‐sulfonamidoacetophenone hydrazones as starting materials is described. This protocol has the salient feature of the use of an inexpensive, abundant and easy‐to‐handle solid alkyne source, effectively avoiding the use of flammable and explosive gaseous acetylene as an original alkyne source. Noble‐metal‐free conditions, wide substrate scope, high yield, and simple workup procedures are advantages of this method. The transformation can also be carried out on a gram scale. [ABSTRACT FROM AUTHOR]

Gentamicin (GM) is one of the commonly used antibiotics in the aminoglycoside class but is ototoxic, which constantly impacts the quality of human life. Pyrroloquinoline quinone (PQQ) as a redox cofactor produced by bacteria was found in soil and foods that exert an antioxidant and redox modulator. It is well documented that the PQQ can alleviate inflammatory responses and cytotoxicity. However, our understanding of PQQ in ototoxicity remains unclear. We reported that PQQ could protect against GM‐induced ototoxicity in House Ear Institute‐Organ of Corti 1 (HEI‐OC1) cells in vitro. To evaluate reactive oxygen species (ROS) production and mitochondrial function, ROS and JC‐1 staining, oxygen consumption rate (OCR), and extracellular acidification rate (ECAR) measurements in living cells, mitochondrial dynamics analysis was performed. GM‐mediated damage was performed by reducing the production of ROS and inhibiting mitochondria biogenesis and dynamics. PQQ ameliorated the cellular oxidative stress and recovered mitochondrial membrane potential, facilitating the recovery of mitochondrial biogenesis and dynamics. Our in vitro findings improve our understanding of the GM‐induced ototoxicity with therapeutic implications for PQQ. Gentamicin (GM), a commonly used antibiotic, is often associated with ototoxicity. PQQ exhibits neuroprotective, cardiovascular, and anti‐tumor effects as potent antioxidants. We found that PQQ protected HEI‐OC1 cells in vitro from gentamicin‐induced ototoxicity. Additionally, PQQ enhanced mitochondrial depolarization and reduced ROS levels while preventing the decline of mitochondrial basal respiration and respiratory capacity, thereby improving mitochondrial dynamic impairments. Our in vitro findings enhance our understanding of the ototoxicity caused by genetically modified organisms and have potential therapeutic implications for PQQ. [ABSTRACT FROM AUTHOR]

Creative objects differ from ordinary objects in that they are created by human beings to contain novel, creative information. Previous research has demonstrated that ordinary object processing involves both a perceptual process for analyzing different features of the visual input and a higher-order process for evaluating the relevance of this visual information. However, it is unclear how and when these processes are influenced by the creative information of the object. This study utilized event-related potentials (ERPs) to investigate the time course of creative object processing. Behavioral results revealed that participants spent more time processing creative objects than they did ordinary objects. Analysis of scalp ERPs further revealed that creative objects elicited a more negative ERP deflection between 190 and 340 ms (N190-340) with an anterior scalp distribution. Additionally, creative objects elicited more positive ERP deflection than did ordinary objects between 400 and 700 ms (P400-700) with a right centro-parietal scalp distribution and between 700 and 1000 ms (late positive component) with a right anterior-central scalp distribution. Such results suggest that the processing of creative objects is composed of two distinct stages. The early perceptual stage involves the detection of visual differences exhibited by the creative objects, while the late stage involves the right-lateralized processes of understanding and encoding the creative information.

As a member of the PGAMs family, PGAM2 has been proved to catalyze the reversible reaction of 3-phosphoglycerate (3-PGA) to 2-phosphoglycerate (2-PGA) in the glycolytic pathway. However, it is unclear whether PGAM2 has a role in regulating differentiation in goat intramuscular preadipocytes. Here, this study was carried to clone the open reading frame (ORF) of goat PGAM2, elucidate its molecular and expressional characteristics, and evaluate the involvement in adipogenesis of intramuscular preadipocytes. According to our findings, the cloned goat PGAM2 gene was 784 bp in full length, including 762 bp of ORF and encoding a protein of 253 amino acids. The expressional level of PGAM2 peaked at 48 hours after induced adipogenic differentiation and was highest in the skeletal muscle of triceps. Moreover, overexpression of PGAM2 transfected by its overexpression plasmid promotes lipid accumulation of goat intramuscular adipocyte as shown by Oil Red O and bodipy staining, accompanied by up-regulating the mRNA levels of peroxisome proliferator-activated receptor γ (PPARγ) (p < 0.001), sterol regulatory element-binding protein 1 (SREBP1) (p < 0.001), CCAAT/Enhancer-binding protein α (C/EBPα) (p < 0.01) and lipoprotein lipase (LPL) (p < 0.01). Taken together, these findings indicate that PGAM2 is a positive regulator for goat intramuscular adipocytes and provide new insights into improvement intramuscular fat deposition in goat meat. [ABSTRACT FROM AUTHOR]