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Abstract Effective vaccination induces memory T cells, which protect the host against pathogen re-infections. Therefore, detection of memory T cells is essential for evaluating vaccine efficacy, which was originally dependent on cytokine induction assays. Currently, two isoforms of CD45 tyrosine phosphatase, CD45RO expression and CD45RA exclusion (CD45RO+/ CD45RA-) are used extensively for detecting memory T cells in cattle. The CD45RO+/CD45RA- markers were first established in humans around three decades ago, and were adopted in cattle soon after. However, in the last two decades, some published data in humans have challenged the initial paradigm, and required multiple markers for identifying memory T cells. On the contrary, memory T cell detection in cattle still mostly relies on CD45RO+/CD45RA- despite some controversial evidence. In this review, we summarized the current literature to examine if CD45RO+/CD45RA- are valid markers for detecting memory T cells in cattle. It seems CD45RA and CD45RO (CD45RA/RO) as markers for identifying bovine memory T cells are questionable.

Toluene was indirectly oxidized and absorbed by micro-nano bubble gas-liquid dispersion system coupled with ceramic membrane. The effects of initial pH of the absorption liquid, toluene concentration and flow rate on the oxidation and absorption efficiencies of toluene were investigated, and the reaction mechanism was also studied. The results showed that the absorption of toluene in the neutral solution was the best, and the absorption efficiencies decreased with the increase of toluene concentration and gas flow rate. Under the optimal conditions of pH 7.00, toluene concentration 256.06 mg/cm³ and gas flow rate 150 mL/min, the absorption efficiency of toluene reached 95.98%. In addition, the degradation products and mechanism analysis showed that ⋅ OH released by micro-nano bubbles oxidized and degraded toluene to form CO2 and water, and it was absorbed in the liquid phase. [ABSTRACT FROM AUTHOR]

Bovine Th2 cells have usually been characterized by IL4 mRNA expression, but it is unclear whether their IL4 protein expression corresponds to transcription. We found that grass-fed healthy beef cattle, which had been regularly exposed to parasites on the grass, had a low frequency of IL4+ Th2 cells during flow cytometry, similar to animals grown in feedlots. To assess the distribution of IL4+ CD4+ T cells across tissues, samples from the blood, spleen, abomasal (draining), and inguinal lymph nodes were examined, which revealed limited IL4 protein detection in the CD4+ T cells across the examined tissues. To determine if bovine CD4+ T cells may develop into Th2 cells, naïve cells were stimulated with anti-bovine CD3 under a Th2 differentiation kit in vitro. The cells produced primarily IFNγ proteins, with only a small fraction (<10%) co-expressing IL4 proteins. Quantitative PCR confirmed elevated IFNγ transcription but no significant change in IL4 transcription. Surprisingly, GATA3, the master regulator of IL4, was highest in naïve CD4+ T cells but was considerably reduced following differentiation. To determine if the differentiated cells were true Th2 cells, an unbiased proteomic assay was carried out. The assay identified 4212 proteins, 422 of which were differently expressed compared to those in naïve cells. Based on these differential proteins, Th2-related upstream components were predicted, including CD3, CD28, IL4, and IL33, demonstrating typical Th2 differentiation. To boost IL4 expression, T cell receptor (TCR) stimulation strength was reduced by lowering anti-CD3 concentrations. Consequently, weak TCR stimulation essentially abolished Th2 expansion and survival. In addition, extra recombinant bovine IL4 (rbIL4) was added during Th2 differentiation, but, despite enhanced expansion, the IL4 level remained unaltered. These findings suggest that, while bovine CD4+ T cells can respond to Th2 differentiation stimuli, the bovine IL4 pathway is not regulated in the same way as in mice and humans. Furthermore, Ostertagia ostertagi (OO) extract, a gastrointestinal nematode in cattle, inhibited signaling via CD3, CD28, IL4, and TLRs/MYD88, indicating that external pathogens can influence bovine Th2 differentiation. In conclusion, though bovine CD4+ T cells can respond to IL4-driven differentiation, IL4 expression is not a defining feature of differentiated bovine Th2 cells. [ABSTRACT FROM AUTHOR]

Diamond possesses extremely excellent properties, which make it a potentially transformative material in an extensive range of applications. Herein, diamonds were synthesized in a FeNiCo–C system with B2S3 as an additive by a temperature-gradient growth method at high temperature and high pressure (HPHT) conditions. The effects of the B2S3 additive in the FeNiCo–C system on diamond crystallization were characterized using Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) measurements. FTIR result shows the presence of positive-charged N+ in the diamond crystal synthesized with the B2S3 additive, and its concentration was estimated to be around 30 ppm. Moreover, the XPS measurements confirm that N+ can combine with boron to form a B–N bond. Furthermore, the Hall effect result indicates that the resistivity of the diamond crystal synthesized with B2S3 was reduced to 3.89 × 10 Ω cm, whereas, the resistivity of the diamond synthesized with the same weight of B2S3 additive along with Ti/Cu as the nitrogen removal agent dropped sharply to 2.51 × 10−1 Ω cm. [ABSTRACT FROM AUTHOR]

In this work, high-quality and centimeter-scale CsPbBr3 perovskite single-crystal thin films were grown using the metal-organic chemical vapor deposition method. Extremely flat surfaces without distinct grain boundaries were observed throughout the thin films. A high polarized degree of approximately 0.52 was measured from the single-crystal thin films by analyzing the polarization of the photoluminescence emission spectra. Low threshold amplified spontaneous emissions with an optical gain coefficient of 1215 cm−1 under the excitation energy of 301 μJ/cm2 and the highest value of 2857 cm−1 under the excitation energy of 1.08 mJ/cm2 were investigated under the excitation of a nanosecond laser at 266 nm. The CsPbBr3 single-crystal thin films showed excellent stability where the optical gain coefficient could be maintained over 1800 cm−1 after exposure to air for ten months. The results of this study not only provide high-quality single-crystal films for laser applications but also put forward a feasible scheme to improve the stability of the materials. [ABSTRACT FROM AUTHOR]

The wet desulphurisation and denitrification technique based on micro-nano bubbles, which is available by either D-method or I-method, is a promising novel process. By employing piped water, Na2SO3 aqueous solution and HA-Na aqueous solution as the absorption liquids, a comparative study was conducted in this article on D-method and I-method to analyze their performance, advantages and disadvantages. It was accompanied by an investigation of how initial pH and initial temperature values of the absorption liquids affected the removal efficiency. The results suggested a positive correlation between NO/SO2 removal efficiencies and pH values but a little improvement in the removal efficiency under alkaline conditions. Furthermore, heating the absorption liquids inhibited the removal of NO and SO2. When manipulated in the same experimental environment, D-method and I-method did not present a significant difference in the SO2 removal efficiency, while the former was remarkably more effective than the latter in removing NO. To put together, D-method had higher removal efficiency, but required a large-scale micro-nano bubble generator to process a large quantity of flue gas as the micro-nano bubble generator was subject to a limited inlet flow rate. Consequently, an increase in investment and operating costs was incurred, while this issue could be avoided by I-method. [ABSTRACT FROM AUTHOR]

With the emergence of nonfullerene acceptors (NFAs), single junction organic solar cells (OSCs) have achieved power conversion efficiencies (PCEs) of over 19%. Due to the intrinsic efficiency limits in low-bandgap NFA OSCs, the donor–to–acceptor energy transfer and acceptor–to–donor hole transfer have considerable impacts on the performance of the OSCs. However, time-resolved ultrafast spectroscopy is often used to prove the energy transfer and hole transfer processes. Herein, we designed thin films and active layers with a tandem structure composed of donors/electron blocking layers/acceptors to demonstrate the occurrence of donor–to–acceptor fluorescence resonance energy transfer (FRET) and acceptor–to–donor hole transfer. By analyzing the steady state photoluminescence peak position and intensity with varied substrate temperatures, FRET from PTO2 to IDTT-IC or IDTT-4FIC and hole transfer from IDTT-IC or IDTT-4FIC to PTO2 were demonstrated. In addition, we monitored devices with a tandem structure active layer using short/long pass filters to excite the donor or acceptor selectively and further confirmed the occurrence of FRET and hole transfer during device operation. Our results proved the effect of FRET and hole transfer directly in thin films and devices, providing a feasible yet practical approach with easily accessible measurements other than ultrafast spectroscopy. [ABSTRACT FROM AUTHOR]