Synergistically Improved Crystallinity and Molecular Doping Ability of Polythiophene-Diketopyrropyrrole Derivatives by m-Trifluoromethylbenzene Containing Side Chains for Improved Thermoelectric Materials.

m-Trifluoromethylbenzene (FB) groups have been widely employed in various fields; however, no studies have reported the use of FB in side chains to enhance the carrier mobility and molecular doping of conjugated polymers. In this study, based on density functional theory (DFT) calculations, we discovered that FB groups can effectively bind to [FeCl4]-, the counterion of the p-type dopant FeCl3, thereby increasing doping ability. Consequently, FB groups were incorporated into the side chains of thiophene-diketopyrrolopyrrole-based donor-acceptor (D-A)-conjugated polymers, and a series of random conjugated polymers were synthesized (denoted as PDPPFB-x, where x represents the molar ratio of the FB side chain). The findings revealed that an appropriate number of FB groups can decrease the π-π stacking distances, enhance the films' crystallinity, and consequently improve the charge transfer ability. Furthermore, after doping with FeCl3, the UV-vis-NIR spectra indicated that the doping efficiency was augmented by increasing the molar fraction of the FB side chain. Among these polymers, PDPPFB-10 exhibited the highest conductivity and power factor, which were 2.0 and 1.5 times higher than those of PDPPFB-0, respectively. These results illustrated a straightforward molecular design strategy for enhancing the crystallinity and conductivity of conjugated polymers, thereby expanding the way to optimize their thermoelectric performance.

Biobased Polybutyrolactam Nanofiber with Excellent Biodegradability and Cell Growth for Sustainable Healthcare Textiles.

The white pollution caused by unsustainable materials is a significant challenge around the globe. Here, a novel and fully biobased polybutyrolactam (PBY) nanofiber membrane was fabricated via the electrospinning method. As-spun PBY nanofiber membranes have good thermal stability, high porosity of up to 71.94%, and excellent wetting behavior. The biodegradability in soil, UV aging irradiation, and seawater was investigated. The PBY nanofiber membrane is almost completely degraded in the soil within 80 days, showing excellent degradability. More interestingly, γ-aminobutyric acid, as a healthcare agent with intrinsic hypotensive, tranquilizing, diuretic, and antidiabetic efficacy, can be detected in the degradation intermediates. In addition, the PBY nanofiber membrane also exhibits antibacterial ability against Escherichia coli. As a fully biomass-derived material, the PBY membrane has excellent biodegradable performance in various environments as well as negligible cytotoxicity and commendable cell proliferation. Our PBY nanofiber membrane shows great potential as biodegradable packaging and in vitro healthcare materials.

Study on the role and molecular mechanism of METTL3-mediated miR-29a-3p in the inflammatory response of spinal tuberculosis.

BACKGROUND: Spinal Tuberculosis (STB) is a common cause of spinal malformation caused by extrapulmonary tuberculosis in developing countries, which seriously affects the quality of life of patients. It was found that the expression of miRNAs in macrophages was stable, specific and readily available after Mycobacterium tuberculosis (MTB) infection. Our research group determined the differential expression of miR-29a-3p in the vertebra of spinal tuberculosis and intervertebral disc lesions through RNAs chip screening and bioinformatics analysis. However, the specific molecular mechanism of miR-29a-3p in the inflammatory response of spinal tuberculosis remains unclear. OBJECTIVE: In this study, we mainly discussed the expression of miR-29a-3p in the focal tissue of spinal tuberculosis and the role and molecular mechanism of miR-29a-3p mediated by METTL3 in the inflammatory response of spinal tuberculosis. METHODS: The tissues of 15 cases of lumbar degenerative diseases and vertebral lesions of spinal tuberculosis were collected, and the THP-1 macrophage model infected by Mycobacterium tuberculosis was constructed, and verified by qRT-PCR, Western blot, fluorescence in situ hybridization, immunohistochemistry, Cell fluorescence and ELISA. RESULTS AND CONCLUSION: We found that the expression of miR-29a-3p was significantly down-regulated in the vertebral body and disc lesion tissues of patients with spinal tuberculosis. Overexpression of miR-29a-3p inhibited the levels of inflammatory factors including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6), and inhibition of miR-29a-3p expression promoted the release of the levels of TNF-α, IL-1ß and IL-6 inflammatory factors. Our study also shows that knockout of methyltransferase 3 (METTL3) can significantly reduce the expression of miR-29a-3p and promote the release of pro-inflammatory cytokines in macrophages.

Analysis of the value of potential biomarker S100-A8 protein in the diagnosis and pathogenesis of spinal tuberculosis.

Objectives: The objective of this study is to evaluate the value of S100-A8 protein as a diagnostic marker for spinal tuberculosis and to explore its role in the potential pathogenesis of spinal tuberculosis (STB). Methods: The peripheral blood of 100 spinal tuberculosis patients admitted to the General Hospital of Ningxia Medical University from September 2018 to June 2021 were collected as the observation group, and the peripheral blood of 30 healthy medical examiners were collected as the control group. Three samples from the observation group and three samples from the control group were selected for proteomics detection and screening of differential proteins. Kyoto Encyclopedia of Genes (KEGG) was used to enrich and analyze related signaling pathways to confirm the target protein. The serum expression levels of the target proteins were determined and compared between the two groups using enzyme-linked immunosorbent assay (ELISA). Statistical methods were used to evaluate the value of target protein as a diagnostic marker for STB. A macrophage model of Mycobacterium tuberculosis infection was constructed and S100-A8 small interfering RNA was used to investigate the molecular mechanism of the target protein. Results: S100-A8 protein has the value of diagnosing spinal tuberculosis (AUC = 0.931, p < 0.001), and the expression level in the peripheral blood of the observation group (59.04 ± 19.37 ng/mL) was significantly higher than that of the control group (43.16 ± 10.07 ng/mL) (p < 0.05). S100-A8 protein expression showed a significant positive correlation with both CRP and ESR values (p < 0.01). Its AUCs for combined bacteriological detection, T-SPOT results, diagnostic imaging, antacid staining results, and pathological results were 0.705 (p < 0.05), 0.754 (p < 0.01), 0.716 (p < 0.01), 0.656 (p < 0.05), and 0.681 (p < 0.01), respectively. Lack of S100-A8 leads to a significant decrease in the expression levels of TLR4 and IL-17A in infected macrophages. Conclusion: S100-A8 protein is differentially expressed in the peripheral blood of patients with spinal tuberculosis and healthy individuals and may be a novel candidate biomarker for the diagnosis of spinal tuberculosis. The feedback loop on the S100-A8-TLR4-IL-17A axis may play an important role in the inflammatory mechanism of spinal tuberculosis.

Analysis of the Value of Serum Biomarker LBP in the Diagnosis of Spinal Tuberculosis.

Objective: To investigate the correlation between the expression of lipopolysaccharide-binding protein (LBP) in peripheral blood of spinal tuberculosis and clinical diagnosis and to evaluate its value as a diagnostic marker of spinal tuberculosis. Methods: In the experimental group, clinical history data and peripheral blood were collected from 100 patients with spinal tuberculosis who were admitted to the Department of Spine Surgery, General Hospital of Ningxia Medical University from May 2017 to May 2020, and peripheral blood was collected from 30 healthy volunteers in the control group. Screening of differential LBP expression by proteomics and ELISA to verify its expression in peripheral blood of spinal tuberculosis patients. t-test, Spearman analysis, linear regression and ROC curve were used to evaluate the diagnostic value of LBP in peripheral blood for spinal tuberculosis. Results: The expression of LBP protein in peripheral blood is significantly higher in patients with spinal tuberculosis than in the normal population; LBP assay values were significantly and positively correlated with CRP and ESR values (P < 0.01); the AUC of LBP in the diagnosis of spinal tuberculosis for pathological examination, bacteriological culture, T-cell spot test for tuberculosis infection (T-SPOT), imaging diagnosis, and acid fast bacillus were, respectively, 0.677 (P < 0.01), 0.707 (P < 0.01), 0.751 (P < 0.01), 0.714 (P < 0.01), and 0.656 (P < 0.05), and there was a correlation between LBP and the diagnostic evaluation of spinal tuberculosis. Conclusion: LBP could be a new candidate biomarker for the diagnosis of spinal tuberculosis.

Activation of surface lattice oxygen in single-atom Pt/CeO2 for low-temperature CO oxidation.

To improve fuel efficiency, advanced combustion engines are being designed to minimize the amount of heat wasted in the exhaust. Hence, future generations of catalysts must perform at temperatures that are 100°C lower than current exhaust-treatment catalysts. Achieving low-temperature activity, while surviving the harsh conditions encountered at high engine loads, remains a formidable challenge. In this study, we demonstrate how atomically dispersed ionic platinum (Pt2+) on ceria (CeO2), which is already thermally stable, can be activated via steam treatment (at 750°C) to simultaneously achieve the goals of low-temperature carbon monoxide (CO) oxidation activity while providing outstanding hydrothermal stability. A new type of active site is created on CeO2 in the vicinity of Pt2+, which provides the improved reactivity. These active sites are stable up to 800°C in oxidizing environments.

Ultrafast measurements of optical spectral coherence by single-shot time-stretch interferometry.

The palette of laser technology has significantly been enriched by the innovations in ultrafast optical pulse generation. Our knowledge of the complex pulse dynamics, which is often highly nonlinear and stochastic in nature, is however limited by the scarcity of technologies that can measure fast variation/fluctuation of the spectral phase (or coherence) and amplitude in real-time, continuously. To achieve this goal, we demonstrate ultrafast interferometry enabled by optical time-stretch for real- time spectral coherence characterization with microsecond-resolution. Accessing the single-shot interferograms continuously, it further reveals the degree of second-order coherence, defined by the cross-spectral density function, at high speed-a capability absent in any existing spectroscopic measurement tools. As the technique can simultaneously measure both the high-speed variations of spectrally resolved coherence and intensity, time-stretch interferometry could create a new arena for ultrafast pulse characterization, especially favorable for probing and understanding the non-repetitive or stochastic dynamics in real-time.

Overcoming the limitation of phase retrieval using Gerchberg-Saxton-like algorithm in optical fiber time-stretch systems.

We investigate the fundamental limitation of the full-field retrieval of optical pulses based on a time-equivalent Gerchberg-Saxton (GS)-like algorithm, in which the Fourier transformation of the temporal signal is performed by the group velocity dispersion (GVD) of optical fibers. The insufficient knowledge of the input pulse intensity fundamentally limited by the bandwidth of the photodetector influences the accuracy of the retrieved phase using the algorithm. To this end, we propose a modified GS algorithm, which involves multi-step intensity-only measurements, to mitigate this limitation. By studying the influence of spectral phase and amplitude modulations on the retrieval error, we show that the modified GS algorithm demonstrates a significant improvement in phase retrieval accuracy. More importantly, we anticipate the present study will provide valuable insight in understanding how the spectral variation generally influences the recovery accuracy in time-stretch-based GS algorithm, and thus identify its potential applications, particularly for those requiring ultrafast measurements.

Spectrally-resolved statistical characterization of seeded supercontinuum suppression using optical time-stretch.

Real-time experimental measurements of the spectrally-resolved noise properties of supercontinuum (SC) have been challenging because of the lack of ultrafast optical spectrometer technologies. Understanding the SC noise is increasingly important because it not only can gain new insight of the complex spectral dynamics of SC generation, but also provides clues to search for stable SC source. Driven by the intense interest in the active seeding mechanism for SC generation, we experimentally demonstrate real-time spectrally-resolved, broadband, statistical characterization of minute continuous-wave (CW) seeded SC, enabled by an ultrahigh-speed spectral acquisition technique called optical time-stretch (OTS). The shot-to-shot statistical analysis shows that the seeded SC exhibits a general compromise between SC bandwidth and spectral stability. OTS also allows us to experimentally identify the seeding condition for SC suppression, in which the spectral broadening is mainly contributed by the cascaded parametric process that delays Akhmediev Breather breakup process and subsequent soliton self-frequency shift. Additionally, the characteristic spectral signature of the Raman solitons, which are becalmed by the minute CW seed, can be clearly captured in real-time by OTS operated at a spectral acquisition rate as high as 20 MHz. We anticipate the OTS technique could provide further new insights for understanding more complex mechanisms of seeded-SC generation which can be examined experimentally.