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The outstanding off-state breakdown performance of lateral drift region organic field-effect transistors (LDR-OFETs) has uncovered the capability of copolymer organic semiconductors (OSCs) in sustaining high voltage. Yet, the breakdown mechanism and performance of LDR-OFET remain unexplored due to the missing mature theories and analytical models. In this article, through the combination of commercial technology computer-aided design (TCAD) tools and fabricated copolymer OSC-based lateral power devices, the avalanche-like breakdown mechanism and impact ionization process are theoretically verified in copolymer OSCs. The fabricated OFET and LDR-OFET feature a poly(methyl methacrylate) (PMMA) and a diketopyrrolopyrrole-based conjugated copolymer (DPPT-TT) thin film as the gate insulator layer and semiconductor layer, respectively. According to the simulations, the equivalent p-n junction and p-i-n junction are formed as the reverse-biased voltage is applied on conventional OFET and LDR-OFET, respectively. The off-state breakdown performance of OFET is therefore determined by the parallel structure of p-n/p-i-n junction and Schottky junction. Both the Schottky contacts and the equivalent p-n/p-i-n junction contribute to the avalanche-like breakdown, yet for the LDR-OFET, the equivalent p-i-n junction takes most part of the applied voltage, guaranteeing it possesses an improved off-state breakdown performance. The good agreement between the simulated and measured results verifies the correctness of the proposed simulation methodology, providing an effective simulation approach for further analysis of copolymer OSC-based lateral power devices.

We report herein an efficient NHC-catalyzed kinetic resolution of acyclic tertiary propargylic alcohols that provides them in high to excellent enantioselectivity. This is the first example of kinetic resolution realized by enantioselective acylation. The recovered enantioenriched alcohols can be facilely converted into other valuable compounds such as densely functionalized tertiary alcohols and carbmates in high yields and excellent stereopurity. Density functional theory calculations were performed to determine the reaction mechanism and to understand the origin of enantiodiscrimination.

Thepotential of organic semiconductors(OSC) in forming power devices has been preliminarily demonstrated recently for their high breakdown performance. As one kind of narrow bandwidth semiconductor, the application of which in the power realm is also limited by its sensitivity to ambient temperature and self-heating effect. In this letter, the thermal stability of breakdown characteristics in the lateral drift region organic field transistor(LDR-OFET) is quantitatively and qualitatively explored. By employing the simple spin-coating process, the fabricated LDR-OFETs consist of a diketopyrrolopyrrole-based polymer(DPPT-TT) layer and a Poly (methyl methacrylate)(PMMA) layer as the semiconductor active layer and insulator layer, respectively. Based on the fabricated devices, the good thermal stability of OSC-based lateral power devices is observed. For the temperature ranges from 300-450K, neither the ambient temperature fluctuation nor the self-heating effect results in thermal runaway, making the copolymer OSC-based power devices capable of maintaining their off-state breakdown performance in a wide temperature range. Such a stable avalanche-like breakdown performance indicates the outstanding potential of OSC-based devices in the power realm.

Background: Mediastinoscope-assisted transhiatal esophagectomy (MATHE) is the most minimally invasive esophagectomy procedure. It is a more challenging procedure and more difficult to be popularized than thoracoscopic surgery. We developed a new MATHE operation mode that provides a clearer visual field and makes the procedures simpler. Methods: A total of 80 patients with esophageal cancer were divided into a control group (n= 29) and a study group (n= 51). The control group underwent classic MATHE, while the study group received modified MATHE. We compared the two groups on operation time; intraoperative blood loss; blood transfusion amount; incidence rate of lung infection, recurrent laryngeal nerves (RLNs) injury, chylothorax, and anastomotic leakage; and upper mediastinal lymph node dissection. Results: The study group was significantly better than the control group in operation time (271.78 min vs. 322.90 min, p< 0.05), intraoperative blood loss (48.63 mL vs. 68.97 mL, p< 0.05), and left paratracheal lymph node (No. 4L) dissection rate (88.24% vs. 24.14%, p< 0.01). No significant differences were identified in the incidence rate of anastomotic leakage, lung complications, or RLNs injury between the two groups. Conclusion: The modified MATHE is easier to perform. Modified MATHE is significantly superior to classic MATHE in operation time, intraoperative blood loss, and upper mediastinal lymph node dissection rate.

Current nucleic acid-responsive DNA hydrogels face significant challenges, such as the requirement for high target concentrations, frequent redesigns, and increased costs, which limit their practical applications in biosensing. To address these issues, we developed a novel biosensing platform integrating a CRISPR/Cas12a system into an RCA-based DNA hydrogel. The hydrogel used in the platform could preencapsulate diverse signal molecules comprising GelRed, methylene blue, and gold nanoparticles, which were released upon Cas12a-mediated cleavage. This design enabled customizable signal output, including fluorescence, electrochemistry, and colorimetry, thereby ensuring the platform’s adaptability to various detection scenarios. Our platform was highly specific for methicillin-resistant Staphylococcus aureus, with a mecAgene detection limit of 10 copies/μL, and provided fast and accurate results within 2 h for clinical samples. Hence, based on these advantages, the proposed biosensing platform exhibits promising application prospects in the field of nucleic acid detection.

Coherent Raman scattering (CRS) microscopy is a chemical imaging modality that provides contrast based on intrinsic biomolecular vibrations. To date, endeavors on instrumentation have advanced CRS into a powerful analytical tool for studies of cell functions and in situ clinical diagnosis. Nevertheless, the small cross-section of Raman scattering sets up a physical boundary for the design space of a CRS system, which trades off speed, signal fidelity and spectral bandwidth. The synergistic combination of instrumentation and computational approaches offers a way to break the trade-off. In this review, we first introduce coherent Raman scattering and recent instrumentation developments, then discuss current computational CRS imaging methods, including compressive micro-spectroscopy, computational volumetric imaging, as well as machine learning algorithms that improve system performance and decipher chemical information. We foresee a constant permeation of computational concepts and algorithms to push the capability boundary of CRS microscopy.

Flow cytometry is one of the most important technologies for high-throughput single-cell analysis. Fluorescent labeling acts as the primary approach for cellular analysis in flow cytometry. Nevertheless, the fluorescent tags are not applicable to all cases, especially to small molecules, for which labeling may significantly perturb the biological functionality. Spontaneous Raman scattering flow cytometry offers the capability to non-invasively detect chemical contents of cells but suffers from slow data acquisition. In order to achieve label-free high-throughput single-particle analysis using Raman scattering, we developed a 32-channel multiplex stimulated Raman scattering flow cytometry (SRS-FC) technique that can measure chemical contents of single particles at a speed of 5 μs per Raman spectrum. Using mixed polymer beads, we demonstrate the discrimination of different particles at a throughput of up to 11,000 particles per second. This is a four orders of magnitude improvement in throughput compared to conventional spontaneous Raman flow cytometry. As a proof of concept, we show the differentiation of 3T3-L1 cells at different states by SRS-FC according to the difference in cellular chemical content. The SRS-FC technique opens new opportunities for high-throughput and high-content chemical analysis of live cells in a label-free manner.

Candida albicans(C. albicans), a major fungal pathogen, causes life-threatening infections in immunocompromised individuals. Fluconazole (FLC) is recommended as first-line therapy for treatment of invasive fungal infections. However, the widespread use of FLC has resulted in increased antifungal resistance among different strains of Candida, especially C. albicans, which is a leading source of hospital-acquired infections. Here, by hyperspectral stimulated Raman scattering imaging of single fungal cells in the fingerprint window and pixel-wise spectral unmixing, we report aberrant ergosteryl ester accumulation in azole-resistant C. albicanscompared to azole-susceptible species. This accumulation was a consequence of de novolipogenesis. Lipid profiling by mass spectroscopy identified ergosterol oleate to be the major species stored in azole-resistant C. albicans. Blocking ergosterol esterification by oleate and suppressing sterol synthesis by FLC synergistically suppressed the viability of C. albicansin vitroand limited the growth of biofilm on mouse skin in vivo. Our findings highlight a metabolic marker and a new therapeutic strategy for targeting azole-resistant C. albicansby interrupting the esterified ergosterol biosynthetic pathway.

Three new manganese-based metal–organic frameworks (Mn-MOFs), [Mn(L)(H2O)]·2DMA (1), [Mn2(L)2(H2O)3]·2DMA (2), and [Mn2(L)2(DMF)2(H2O)]·3DMF (3), have been synthesized with the ligand H2L (N-phenyl-N′-phenylbicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxdiimide dicarboxylic acid). The secondary building units (SBUs) of the Mn-MOFs are controlled by changing the anions of the manganese salts, and the structures are modified from two-fold interpenetrating to non-interpenetrating by adjusting the mixed solvent systems. Along with the structural modification of the Mn-MOFs, we optimized their catalytic activities for the reaction of CO2and epoxides toward cyclic carbonates. Both the activity and reusability of the Mn-MOFs are successfully improved in the solvent-free cycloaddition of CO2with various epoxides under the mild conditions of atmospheric pressure and 70 °C.