Transesophageal echocardiography: A bibliometric analysis from 1979 to 2022.

OBJECTIVE: Heart disease poses a significant global health challenge. Transesophageal echocardiography (TEE) has gained prominence in clinical practice because of advancements in visual medicine. The present bibliometric analysis provides an overview of TEE research, identifies trends, and highlights emerging topics. METHODS: A comprehensive search of TEE-related literature from the establishment of the Web of Science Core Collection (WOSCC) until 2022 was conducted. Utilizing the CiteSpace software, we performed an in-depth analysis of the literature data encompassing disciplines, publication years, countries, institutions, authors, journals, cited references, and keywords. RESULTS: A total of 17 032 TEE-related articles were included in this study. The most active disciplines in TEE research were Cardiac & Cardiovascular Systems, Anesthesiology, and Respiratory System. The number of publications displayed a consistent upward trajectory over the years. Notably, research contributions predominantly originated from developed countries, mainly Europe and North America, with the United States, Germany, Italy, and Japan leading the way. Analysis of institutions, authors, and journals revealed the United States' significant role in TEE research. Furthermore, the analysis of cited references and keywords identified the treatment of patent foramen ovale and its association with stroke as emerging hot topics in recent years. CONCLUSIONS: This study highlights that TEE remains a research hotspot, with the United States at the forefront. Future research should investigate the relationship between heart disease and brain function.

Molecular Mechanism of Sevoflurane Affecting Fetal Nervous System's Development Through the GABAAR/Sirt 1 Pathway.

Objective: To investigate the molecular mechanism of sevoflurane affecting the development of the offspring's nervous system through the GABAAR/Sirt 1 pathway. Methods: Pregnant rats were obtained by mating females and males, and were randomly divided into 3 h sevoflurane (2.3% sevoflurane anesthesia for 3 h), 6 h sevoflurane (2.3% sevoflurane anesthesia for 6 h), Sirt-1 activator-SRT1720 (10 mg/kg SRT1720), 6 h sevoflurane+SRT1720 (10 mg/kg SRT1720) and control groups) group and control group, 31-day-old littermates were taken out and their learning and memory functions were examined by the water maze experiment; the heads were severed to remove the brains, and the kits were used to detect the levels of 5-HT and Ach in the brain tissue; the hippocampal tissues of the littermates were isolated, and neuronal damage in the hippocampal tissues was assessed by Nissen staining; neuronal apoptosis in the hippocampal tissues was detected by TUNEL staining; and GABAAR in the hippocampal tissues was detected by Western blot. GABAAR, Sirt-1, and apoptosis-related proteins (Caspase-3, BCL-2, BAX) in hippocampal tissue. Results: Compared with the control group, the 3 h sevoflurane group and the 6 h sevoflurane group neurons were arranged sparsely, the cells appeared to be swollen, the evasion latency, the apoptosis rate of neurons, the expression of Caspase-3, and BAX increased significantly, and the number of crossing the plateau, the level of 5-HT and Ach in the brain tissues, and the expression of GABAAR, Sirt-1, and BCL-2 were decreased significantly, and the differences existed between the groups (P < .5); compared with the 6 h sevoflurane group, neuronal morphological changes in the hippocampal tissue of the 6 h sevoflurane+SRT1720 group were improved, with a significant decrease in the evasion latency, neuronal apoptosis rate, expression of Caspase-3 and BAX, and a significant increase in the number of traversing platforms, brain tissue 5-HT, Ach level, GABAAR, Sirt-1, and BCL-2 expression (P < .5); compared with the SRT1720 group, the neurons in the 6 h sevoflurane + SRT1720 group were sparsely arranged, with a significant increase in evasion latency, neuronal apoptosis rate, caspase-3, BAX expression, and a significant decrease in the number of traversing platforms, brain tissue 5-HT, Ach level, GABAAR, Sirt-1, and BCL-2 expression (P < .5 ). Conclusion: Sevoflurane can affect the neurological development of rat offspring, which may be related to the inhibition of Sirt-1 expression.

High-resolution real-time Fourier transform based on optical frequency comb injected frequency shifting loop.

A high-resolution real-time Fourier transform scheme is proposed and demonstrated based on injecting an optical frequency comb (OFC) into a frequency shifting loop (FSL). Through setting the frequency interval between neighboring teeth in the coherent OFC to be equal to an integer multiple of the frequency shift and also the free spectral range of the FSL, the number of the effective signal replicas from the FSL is increased by M times, where M is the tooth number of the OFC. Hence, it breaks the limitation on the number of round trips due to the gain saturation effect and the cumulative amplified spontaneous emission noise in the FSL under a single optical carrier injection, which greatly enhances the frequency resolution. In the experiment, a coherent three-tone optical carrier is injected into an FSL to realize real-time spectrum analysis, where the frequency resolution is enhanced by three times compared with that by using a single-tone optical carrier injection, i.e., from 60 kHz to 20 kHz.

Instantaneous bandwidth expansion of photonic sampling analog-to-digital conversion for linear frequency modulation waveforms based on up-sampling and fractional Fourier transform signal processing.

An approach to expanding the instantaneous bandwidth of a photonic sampling analog-to-digital converter (ADC) for receiving linear frequency modulation waveforms (LFMWs) is proposed and experimentally demonstrated based on up-sampling and filtering in the fractional Fourier domain. Through twice zero interpolation, the equivalent sampling rate is quadrupled, which also quadruples the nominal instantaneous bandwidth of the photonic sampling ADC. In addition, with the assistance of bandpass filtering in the fraction Fourier domain, the image signals and the harmonic distortions generated in the interpolation process are filtered out. As a result, the effective instantaneous bandwidth of the photonic sampling ADC is doubled. In the experiment, the instantaneous bandwidth of a photonic sampling ADC with a sampling rate of 5 GSa/s for receiving LFMWs is increased from 2.5 GHz to 5 GHz by using the proposed method. Input LFMWs within the frequency range of 24-27 GHz and 30-33 GHz, i.e., with an instantaneous bandwidth of 3 GHz, are digitized without frequency-domain aliasing. Besides, the ability of the proposed method to enhance the ranging accuracy in a broadband radar system is demonstrated. This method reduces the hardware complexity of the photonic sampling ADC for receiving broadband LFMWs in radar systems.

Modular-Approach Synthesis of Giant Molecule Acceptors via Lewis-Acid-Catalyzed Knoevenagel Condensation for Stable Polymer Solar Cells.

The operational stability of polymer solar cells is a critical concern with respect to the thermodynamic relaxation of acceptor-donor-acceptor (A-D-A) or A-DA'D-A structured small-molecule acceptors (SMAs) within their blends with polymer donors. Giant molecule acceptors (GMAs) bearing SMAs as subunits offer a solution to this issue, while their classical synthesis via the Stille coupling suffers from low reaction efficiency and difficulty in obtaining mono-brominated SMA, rendering the approach impractical for their large-scale and low-cost preparation. In this study, we present a simple and cost-effective solution to this challenge through Lewis acid-catalyzed Knoevenagel condensation with boron trifluoride etherate (BF3 ⋅ OEt2 ) as catalyst. We demonstrated that the coupling of the monoaldehyde-terminated A-D-CHO unit and the methylene-based A-link-A (or its silyl enol ether counterpart) substrates can be quantitatively achieved within 30 minutes in the presence of acetic anhydride, affording a variety of GMAs connected via the flexible and conjugated linkers. The photophysical properties was fully studied, yielding a high device efficiency of over 18 %. Our findings offer a promising alternative for the modular synthesis of GMAs with high yields, easier work up, and the widespread application of such methodology will undoubtedly accelerate the progress of stable polymer solar cells.

Photonic sampling analog-to-digital conversion based on time and wavelength interleaved ultra-short optical pulse train generated by using monolithic integrated LNOI intensity and phase modulator.

High-speed analog-to-digital conversion (ADC) is experimentally demonstrated by employing a time and wavelength interleaved ultra-short optical pulse train to achieve photonic sampling and using wavelength division demultiplexing to realize speed matching between the fast optical front-end and the slow electronic back-end. The sampling optical pulse train is generated from a cavity-less ultra-short optical pulse source involving a packaged device that monolithically integrates an intensity modulator and a phase modulator into a chip based on lithium niobate on insulator (LNOI). In the experiment, the fiber-to-fiber insertion loss of the packaged modulation device is measured to be 6.9 dB. In addition, the half-wave voltages of the Mach-Zehnder modulator and the phase modulator in the LNOI-based modulation device are measured to be 3.6 V and 3.4 V at 5 GHz, respectively. These parameters and the device size are superior to those based on cascaded commercial devices. Through using the packaged modulation device, two ultra-short optical pulse trains centered at 1541.40 nm and 1555.64 nm are generated with time jitters of 19.2 fs and 18.9 fs in the integral offset frequency range of 1 kHz to 10 MHz, respectively, and are perfectly time interleaved into a single pulse train with a repetition rate of 10 GHz and a time jitter of 19.8 fs. Based on the time and wavelength interleaved ultra-short optical pulse train, direct digitization of microwave signals within the frequency range of 1 GHz to 40 GHz is demonstrated by using a two-channel wavelength demultiplexing photonic ADC architecture, where the effective number of bits are 5.85 bits and 3.75 bits for the input signal at 1.1 GHz and 36.3 GHz, respectively.

Broadband high-resolution microwave frequency measurement based on photonic undersampling via using three cavity-less optical pulse sources with coprime repetition rates.

A photonic-assisted broadband and high-resolution microwave frequency measurement scheme is proposed and demonstrated based on undersampling via using three cavity-less optical pulse sources with coprime repetition rates. After undersampling by three ultrashort pulse trains with repetition rates in the order of gigahertz, input microwave signal is down-converted to three intermediate-frequency (IF) signals located in the first Nyquist frequency range. Through measuring the frequencies of the IF signals via fast Fourier transform after digitization by the commercially available analog-to-digital convertors, the input microwave signal frequency can be retrieved based on the frequency identification algorithm. In the proof-of-concept experiment, three ultrashort pulse trains with repetition rates of 2.99, 3.07, and 3.10 GHz are generated by a cavity-less optical pulse source, where the pulse widths are 9.5, 9.6, and 9.8 ps, respectively. Through using these three ultrashort optical pulse trains, a frequency measurement range up to 40 GHz is realized, where the frequency measurement error is less than ±5kHz, and the spurious-free dynamic range is 91.25dBcHz2/3.

Tunable dual-passband microwave photonic filter with a fixed frequency interval using phase-to-intensity modulation conversion by stimulated Brillouin scattering.

An approach to realizing a highly selective and stable tunable dual-passband microwave photonic filter (MPF) is proposed and experimentally demonstrated, in which two passbands have a fixed frequency interval. The MPF is achieved based on phase-to-intensity modulation (PM-IM) conversion by stimulated Brillouin scattering (SBS). The kernel of the proposed scheme is generating a two-tone pump by first frequency-downshifting the optical carrier through self-induced SBS in a spool of single-mode fiber (SMF), and then modulating it in carrier-suppressed double-sideband modulation mode. Making use of Brillouin frequency shift difference between the SMF and the high nonlinear fiber used for PM-IM conversion, two passbands with a fixed frequency interval equal to 2 times the Brillouin frequency shift difference between the two fibers can be achieved. Through simply varying the modulation frequency, the two passbands can be synchronously shifted back and forth. In the experiment, a tunable dual-passband MPF with a fixed frequency interval of 2.434 GHz is demonstrated in the frequency range of 0-9.644 GHz, where the out-of-band rejection ratio and the 3-dB bandwidth of the passbands are measured to be larger than 20 dB and smaller than 57 MHz, respectively.

Palladium-catalyzed direct arylation of phenols with aryl iodides.

An efficient protocol of palladium-catalyzed direct para-arylation of unfunctionalized phenols with aryl iodides under mild conditions was reported. A variety of substrates were applied in this reaction with yields up to 87%.

Synthesis of dibenzothiophenes by Pd-catalyzed dual C-H activation from diaryl sulfides.

Palladium-catalyzed dual C-H functionalization of diaryl sulfides to form dibenzothiophenes (DBTs) by oxidative dehydrogenative cyclization is reported. This protocol afforded various DBTs in moderate to good yields with tolerance of a wide variety of substrates. Benzo[1,2-b:4,5-b']bis[b]benzothiophene was successfully synthesized by this method, which was used as an organic semiconductor for field-effect transistors.

Revolutionizing cancer treatment: enhancing CAR-T cell therapy with CRISPR/Cas9 gene editing technology.

CAR-T cell therapy, a novel immunotherapy, has made significant breakthroughs in clinical practice, particularly in treating B-cell-associated leukemia and lymphoma. However, it still faces challenges such as poor persistence, limited proliferation capacity, high manufacturing costs, and suboptimal efficacy. CRISPR/Cas system, an efficient and simple method for precise gene editing, offers new possibilities for optimizing CAR-T cells. It can increase the function of CAR-T cells and reduce manufacturing costs. The combination of CRISPR/Cas9 technology and CAR-T cell therapy may promote the development of this therapy and provide more effective and personalized treatment for cancer patients. Meanwhile, the safety issues surrounding the application of this technology in CAR-T cells require further research and evaluation. Future research should focus on improving the accuracy and safety of CRISPR/Cas9 technology to facilitate the better development and application of CAR-T cell therapy. This review focuses on the application of CRISPR/Cas9 technology in CAR-T cell therapy, including eliminating the inhibitory effect of immune checkpoints, enhancing the ability of CAR-T cells to resist exhaustion, assisting in the construction of universal CAR-T cells, reducing the manufacturing costs of CAR-T cells, and the security problems faced. The objective is to show the revolutionary role of CRISPR/Cas9 technology in CAR-T cell therapy for researchers.

Copper-catalyzed formation of N,N-dimethyl benzamide from nitrile and DMF under an O2 atmosphere.

Amidation of nitrile with N,N-dimethylformamide (DMF) was catalyzed by Cu2O with 1,10-phenanthroline as a ligand under an oxygen atmosphere. A variety of N,N-dimethyl benzamides were obtained in yields up to 84%.

Synthesis of disulfides and diselenides by copper-catalyzed coupling reactions in water.

A simple and efficient protocol for copper-catalyzed coupling reactions between aryl halides and elemental sulfur or selenium has been developed. A variety of disulfides and diselenides can be obtained in moderate to excellent yields up to 96%.

Cu-catalyzed three-component synthesis of substituted benzothiazoles in water.

Three in one: Copper-catalyzed three-component reactions, involving 2-iodoanilines, aldehydes, and sulfur powder, afford 2-phenylbenzothiazoles in water. A variety of 2-substituted benzothiazoles can be obtained in good to excellent yields of up to 96 % (see scheme).

Hierarchical Multiobjective Heuristic for PCB Assembly Optimization in a Beam-Head Surface Mounter.

This article proposes a hierarchical multiobjective heuristic (HMOH) to optimize printed-circuit board assembly (PCBA) in a single beam-head surface mounter. The beam-head surface mounter is the core facility in a high-mix and low-volume PCBA line. However, as a large-scale, complex, and multiobjective combinatorial optimization problem, the PCBA optimization of the beam-head surface mounter is still a challenge. This article provides a framework for optimizing all the interrelated objectives, which has not been achieved in the existing studies. A novel decomposition strategy is applied. This helps to closely model the real-world problem as the head task assignment problem (HTAP) and the pickup-and-place sequencing problem (PAPSP). These two models consider all the factors affecting the assembly time, including the number of pickup-and-place (PAP) cycles, nozzle changes, simultaneous pickups, and the PAP distances. Specifically, HTAP consists of the nozzle assignment and component allocation, while PAPSP comprises place allocation, feeder set assignment, and place sequencing problems. Adhering strictly to the lexicographic method, the HMOH solves these subproblems in a descending order of importance of their involved objectives. Exploiting the expert knowledge, each subproblem is solved by an elaborately designed heuristic. Finally, the proposed HMOH realizes the complete and optimal PCBA decision making in real time. Using industrial PCB datasets, the superiority of HMOH is elucidated through comparison with the built-in optimizer of the widely used Samsung SM482.

MiR-129-5p Restrains Apatinib Resistance in Human Gastric Cancer Cells Via Downregulating HOXC10.

Background: Repeated administration of apatinib has resulted in serious drug resistance in gastric cancer (GC). Previous studies showed that miR-129-5p had a low expression in GC, and homeobox gene C10 (HOXC10), a carcinogenic gene, was highly expressed in GC, while the molecular mechanism of miR-129-5p involved in apatinib resistance in GC cells is still unclear. Materials and Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression levels of miR-129-5p and HOXC10 in GC tissues or cell lines. The expression levels of associated proteins were detected by Western blot. Cell counting kit-8 (CCK-8), the 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), and flow cytometry assays were conducted to detect cell viability, proliferation, and apoptosis of MGC-803/AP and AGS/AP cells in vitro. The dual-luciferase reporter assay was used to verify the targeted relationship between miR-129-5p and HOXC10. The xenograft model was established to examine the effect of miR-129-5p in vivo, and the HOXC10 protein expression in tumor xenograft was assessed by immunohistochemistry. Results: MiR-129-5p had a low expression in GC tissues and apatinib-resistant cell lines, while HOXC10 was highly expressed. Meanwhile, overexpression of miR-129-5p and knockdown of HOXC10 could enhance the chemosensitivity of MGC-803/AP and AGS/AP cells. Dual-luciferase reporter assay confirmed miR-129-5p targeted HOXC10 and downregulated its expression level. MiR-129-5p inhibited proliferation and promoted apoptosis of MGC-803/AP and AGS/AP cells by downregulating HOXC10. The experiment in vivo also confirmed that miR-129-5p reduced apatinib resistance in GC cells by targetedly inhibiting HOXC10. HOXC10 was upregulated in GC tumor xenograft tissues. Conclusion: miR-129-5p restrains apatinib-resistant of GC cells by regulating HOXC10.

Validation of oil fate and mass balance for the Deepwater Horizon oil spill: Evaluation of water column partitioning.

Model predictions of oil transport and fate for the 2010 Deepwater Horizon oil spill (Gulf of Mexico) were compared to field observations and absolute and relative concentrations of oil compounds in samples from 900 to 1400 m depth <11 km from the well. Chemical partitioning analyses using quantitative indices support a bimodal droplet size distribution model for oil released during subsea dispersant applications in June with 74% of the mass in >1 mm droplets that surfaced near the spill site within a few hours, and 1-8% as <0.13 mm microdroplets that remained below 900 m. Analyses focused on 900-1400 m depth <11 km from the well indicate there was substantial biodegradation of dissolved components, some biodegradation in microdroplets, recirculation of weathered microdroplets into the wellhead area, and marine oil snow settling from above 900 m carrying more-weathered particulate oil into the deep plume.

Oil fate and mass balance for the Deepwater Horizon oil spill.

Based on oil fate modeling of the Deepwater Horizon spill through August 2010, during June and July 2010, ~89% of the oil surfaced, ~5% entered (by dissolving or as microdroplets) the deep plume (>900 m), and ~6% dissolved and biodegraded between 900 m and 40 m. Subsea dispersant application reduced surfacing oil by ~7% and evaporation of volatiles by ~26%. By July 2011, of the total oil, ~41% evaporated, ~15% was ashore and in nearshore (<10 m) sediments, ~3% was removed by responders, ~38.4% was in the water column (partially degraded; 29% shallower and 9.4% deeper than 40 m), and ~2.6% sedimented in waters >10 m (including 1.5% after August 2010). Volatile and soluble fractions that did not evaporate biodegraded by the end of August 2010, leaving residual oil to disperse and potentially settle. Model estimates were validated by comparison to field observations of floating oil and atmospheric emissions.

Fabrication of nano/microstructures for SERS substrates using an electrochemical method.

Based on an electrochemical method, three-dimensional arrayed nanopore structures are machined onto a Mg surface. The structured Mg surface is coated with a thin gold (Au) film, which is used as a surface-enhanced Raman scattering (SERS) substrate. A rhodamine 6G (R6G) probe molecule is used as the detection agent for the SERS measurement. Different sizes of arrayed micro/nanostructures are fabricated by different treatment time using the electrochemical process. The topographies of these micro/nanostructures and the thickness of the Au film have an influence on the Raman intensity of the Mg substrate. Furthermore, when the thickness of Au film coating is held constant, the Raman intensity on the structured Mg substrates is about five times higher after a treatment time of 1 min when compared with other treatment times. The SERS enhancement factor ranges from 106 to 1.75 × 107 under these experimental conditions. Additionally, a 10-6 mol·L-1 solution of lysozyme was successfully detected using the Mg-Au nanopore substrates. Our low-cost method is reproducible, homogeneous, and suitable for the fabrication of SERS substrates.

A lysosome-targetable and ratiometric fluorescent probe for hypochlorous acid in living cells based on a 1,8-naphthalimide derivative.

Hypochlorous acid (HClO) is an important reactive oxygen species (ROS) and plays a significant role in living organisms. Highly selective and lysosome-targetable probes for sensing hypochlorous acid are rare. In this article, we designed and prepared a new lysosome-targeting and ratiometric fluorescent probe for monitoring the levels of hypochlorous acid. 4-Aminonaphthalimide was chosen as the fluorescent group and (2-aminoethyl) thiourea group was used as a specific recognition group for HClO. A morpholine unit was employed as a lysosome-targeting group. In the absence of HClO the probe underwent intramolecular charge transfer (ICT) and showed a green emission. When excess HClO is present, the ICT process was interrupted which caused a 57 nm blue-shift of fluorescence emission from 533 nm to 476 nm. The ratiometric fluorescent probe showed outstanding selectivity toward HClO over other various bioactive species. Furthermore, the ratiometric fluorescent probe exhibited rapid response time and ability of working in a wide pH range. The linear response of I476nm/I533nm toward HClO was obtained in a concentration range of HClO from 1.0 × 10-6 to 1.0 × 10-4 mol·L-1. The detection limit was estimated to be 8.0 × 10-7 mol·L-1 for HClO. Moreover, the probe showed a perfect lysosome-targeting ability, and has been successfully used to the confocal imaging of HClO in lysosomes of HepG2 cells with little cell toxicity. All of such good properties illustrated that it could be applied to determine HClO at lysosomes in living cells.