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1.
J Int Med Res ; 52(3): 3000605241232920, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38518199

ABSTRACT

OBJECTIVE: This study was performed to examine the possible association of iron overload with infectious complications and survival among liver transplant recipients. METHODS: We conducted a systematic review and meta-analysis of studies published in the PubMed, Embase, Web of Science, and Cochrane Library databases up to September 2022. Hazard ratios (HRs) and 95% confidence intervals (CIs) were extracted to estimate the association of iron overload with infectious outcomes and overall survival after liver transplantation. RESULTS: Eight studies involving 2817 recipients met the inclusion criteria. Iron overload was strongly associated with an increased risk of infection after liver transplantation (HR, 1.66; 95% CI, 1.03-2.68). An increase in the serum ferritin level was associated with an increased risk of infection after liver transplantation (HR, 1.44; 95% CI, 1.09-1.91). Iron overload was a significant predictor of worse overall survival (HR, 1.35; 95% CI, 1.11-1.64). In addition, a high serum ferritin level was significantly associated with an increased risk of death (HR, 1.34; 95% CI, 1.10-1.64). CONCLUSION: Iron overload may be associated with a higher risk of infectious complications and a worse prognosis among liver transplant recipients.


Subject(s)
Iron Overload , Liver Transplantation , Humans , Iron/metabolism , Liver Transplantation/adverse effects , Iron Overload/complications , Prognosis , Ferritins
2.
Chemistry ; 30(28): e202400527, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38470123

ABSTRACT

Owing to distinct physicochemical properties in comparison to gold and silver counterparts, atomically precise copper nanoclusters are attracting embryonic interest in material science. The introduction of copper cluster nanomaterials in more interesting fields is currently urgent and desired. Reported in this work are novel copper nanoclusters of [XCu54Cl12(tBuS)20(NO3)12] (X=S or none, tBuSH=2-methyl-2-propanethiol), which exhibit high performance in photothermal conversion. The clusters have been prepared in one pot and characterized by combinatorial techniques including ultraviolet-visible spectroscopy (UV-vis), electrospray ionization mass spectrometry (ESI-MS), and X-ray photoelectron spectroscopy (XPS). The molecular structure of the clusters, as revealed by single crystal X-ray diffraction analysis (SCXRD), shows the concentric three-shell Russian doll arrangement of X@Cu14@Cl12@Cu40. Interestingly, the [SCu54Cl12(tBuS)20(NO3)12] cluster contains 8 free valence electrons in its structure, making it the first eight-electron copper nanocluster stabilized by thiolates. More impressively, the clusters possess an effective photothermal conversion (temperature increases by 71 °C within ~50 s, λex=445 nm, 0.5 W cm-2) in a wide wavelength range (either blue or near-infrared). The photothermal conversion can be even driven under irradiation of simulated sunlight (3 sun), endowing the clusters with great potency in solar energy utilization.

3.
Opt Express ; 31(19): 30030-30039, 2023 Sep 11.
Article in English | MEDLINE | ID: mdl-37710555

ABSTRACT

Analyzing the longitudinal-mode of a pump can significantly prevent optical damage to solid media and expand the applications of solid media in high repetition rate stimulated Brillouin scattering (SBS). In this study, a Fabry-Pérot etalon was used to control the number of longitudinal-mode in a pump laser output. We studied the output characteristics of SBS in fused silica by considering both single- and multi-longitudinal-mode pumping. We analyzed and compared variations in the SBS threshold, energy reflectivity, linewidth, and waveform characteristics. The experimental results indicated that a pump operating in a single-longitudinal-mode had a 14% lower SBS threshold than one operating in a multi-longitudinal-mode. The proportion of the weak longitudinal-mode in the multi-longitudinal-mode was close to the threshold difference. The damage threshold of the multi-longitudinal-mode pumps was approximately 35 mJ (@12 ns, f = 300 mm). The Stokes linewidth and waveform exhibited opposite trends as the energy changed. Due to the time-bandwidth product, the linewidth and waveform tended to converge towards the pump. This study emphasizes the importance of using a single-longitudinal-mode pump in the development and use of solid-state SBS gain media.

4.
iScience ; 26(10): 107850, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37752951

ABSTRACT

The atomically precise metal electrocatalysts for driving CO2 reduction reactions are eagerly pursued as they are model systems to identify the active sites, understand the reaction mechanism, and further guide the exploration of efficient and practical metal nanocatalysts. Reported herein is a nanocluster-based electrocatalyst for CO2 reduction, which features a clear geometric and electronic structure, and more importantly excellent performance. The nanocatalysts with the molecular formula of [Ag17Cu10(dppm)4(PhC≡C)20H4]3+ have been obtained in a facile way. The unique metal framework of the cluster, with silver, copper, and hydride included, and dedicated surface structure, with strong (dppm) and labile (alkynyl) ligands coordinated, endow the cluster with excellent performance in electrochemical CO2 reduction reaction to CO. With the atomically precise electrocatalysts in hand, not only high reactivity and selectivity (Faradaic efficiency for CO up to 91.6%) but also long-term stability (24 h), are achieved.

6.
Opt Express ; 31(4): 5699-5707, 2023 Feb 13.
Article in English | MEDLINE | ID: mdl-36823843

ABSTRACT

Stimulated Brillouin scattering (SBS) is a non-linear process which has the capacity to improve the beam quality and pulse characteristics of laser beams. In this paper, we theoretically and experimentally study the process of SBS in fused silica. In particular, we examine the energy reflection and pulse compression of input laser pulses as functions of focus position, pump energy and beam diameter. We utilized coupled wave equations and a distributed noise model to simulate the reflected energy and time waveform under different gain parameters. An experimental system is constructed and used to qualify the numerical simulations. The results reveal that the threshold for the SBS process and the energy reflectivity significantly change with laser focus position under the same pump and focusing parameters. Ultimately, the gain characteristics of the SBS material is the primary factor that influences the SBS output. This work presented here offers insight into the operation of short-length solid-state SBS lasers and serves as a basis for the design and optimization of such systems.

7.
Chemistry ; 29(13): e202203022, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36367372

ABSTRACT

Past decades have witnessed the generation of new stretchable photodetectors in electronic eyes, health sensing, wearable devices, intelligent monitoring and other fields. Stretchable devices require not only outstanding performance but also excellent flexibility, adaptability and stability. Innovative strategies have been proposed to realize the stretchability of devices. In addition, novel functional materials including zero-dimensional nanomaterials, one-dimensional inorganic nanomaterials, two-dimensional layered materials, organic materials, and organic-inorganic composite materials with excellent properties are emerging to continuously improve the performance of devices. Here, the recent research progress of stretchable photodetectors in terms of both various design methods and functional materials is outlined. The optical performance and stretchable properties are also comprehensively reviewed. Finally, a summary and the challenges associated with the application of stretchable photodetectors are presented.

8.
Opt Express ; 30(17): 30600-30610, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-36242160

ABSTRACT

Delayed self-heterodyne interferometry is a commonly used technique for the measurement of laser linewidth. It typically requires the use of a very long delay fiber when measuring narrow linewidth (especially linewidths in the kHz-range) lasers. The use of long fibers can result in system losses and the introduction of 1/f noise that causes spectral line broadening. In this paper, we present a calculation method for processing the output of a delayed self-heterodyne setup using a short length of delay fiber, to determine laser linewidth. The method makes use of pairs of data points (corresponding to adjacent maxima and/or minima) in the signal generated from the self-heterodyne setup to determine the laser linewidth. Here, the power ratio or amplitude difference of the signal at these data points is of importance. One of the key benefits of this method is that it avoids 1/f noise which would otherwise be introduced into the measurement through the application of long fibers. The experimental results highlight that the method has a high calculation accuracy. Furthermore, the capacity for the method to utilize different pairs of data points in the self-heterodyne output to determine the laser linewidth, imparts a high degree of flexibility and usability to the technique when applied to real-world measurements.

9.
Front Psychol ; 13: 912355, 2022.
Article in English | MEDLINE | ID: mdl-35967671

ABSTRACT

Under the background of sustainable development, China's economic growth engine becomes innovation-driven, and it is an important way for China to rapidly improve its green innovation capability by opening up to the outside world and utilizing the spillover effect of international technology. In this article, the system quality evaluation system is reconstructed by the method of fully arranged polygonal graphical indicators, and the provincial system quality in China is measured and added into the model as a regulating variable. The dynamic panel method and the dynamic threshold panel method are used to test the direct effects of foreign direct investment (FDI) and foreign trade on green innovation capability, the interaction effect of institutional quality, and the threshold effect. Empirical results show that the three technology spillovers have significantly promoted China's green innovation capability. System quality will affect the determining coefficient of international technology spillovers on China's green innovation capability. The positive promoting effects of FDI and foreign trade on China's green innovation capability, all increase with the improvement of China's system quality. Therefore, when utilizing FDI and foreign trade to promote green innovation in each region, each region should consider creating a good institutional environment for the emergence of international technological effects.

10.
Micromachines (Basel) ; 13(8)2022 Aug 13.
Article in English | MEDLINE | ID: mdl-36014233

ABSTRACT

Delayed self-heterodyne/homodyne measurements based on an unbalanced interferometer are the most used methods for measuring the linewidth of narrow-linewidth lasers. They typically require the service of a delay of six times (or greater) than the laser coherence time to guarantee the Lorentzian characteristics of the beat notes. Otherwise, the beat notes are displayed as a coherent envelope. The linewidth cannot be directly determined from the coherence envelope. However, measuring narrow linewidths using traditional methods introduces significant errors due to the 1/f frequency noise. Here, a short fiber-based linewidth measurement scheme was proposed, and the influence of the noise floor on the measurement of the laser linewidth using this scheme was studied theoretically and experimentally. The results showed that this solution and calibration process is capable of significantly improving the measurement accuracy of narrow linewidth.

11.
Mamm Genome ; 32(6): 530-536, 2021 12.
Article in English | MEDLINE | ID: mdl-34665305

ABSTRACT

TLR8-AS1 has been characterized as an oncogenic lncRNA in ovarian cancer, while its role in hepatocellular carcinoma (HCC) is unknown. This study aimed to explore the role of TLR8-AS1 in HCC. TLR8-AS1 expression in HCC and paired non-tumor tissues from 62 HCC patients was determined by RT-qPCR. The prognostic value of TLR8-AS1 for HCC was analyzed by performing a 5-year follow-up. Correlations between TLR8-AS1 and mature miR-34a and miR-34a precursor were analyzed by Pearson's correlation coefficient. The roles of TLR8-AS1 and miR-34a in regulating the proliferation and migration were explored by CCK-8 assay and Transwell migration assay. We found that TLR8-AS1 was upregulated in HCC and predicted poor survival. Across HCC tissues, TLR8-AS1 was inversely correlated with mature miR-34a, but not miR-34a precursor. In HCC cells, TLR8-AS1 overexpression downregulated mature miR-34a, but not miR-34a precursor. Cell proliferation and Transwell migration assay showed that TLR8-AS1 overexpression reduced the enhancing effects of miR-34a on cell proliferation and migration. TLR8-AS1 may suppress miR-34a maturation in HCC to suppress cell proliferation and migration.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , MicroRNAs , RNA, Long Noncoding , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic , Humans , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Toll-Like Receptor 8/genetics , Toll-Like Receptor 8/metabolism
12.
Appl Opt ; 59(9): 2892-2896, 2020 Mar 20.
Article in English | MEDLINE | ID: mdl-32225839

ABSTRACT

The novel two-dimensional (2D) elementary tellurium is currently of great interest in optoelectronic and photonic applications. In this contribution, 2D tellurium nanosheets were successfully created by using the liquid-phase exfoliation method. With the as-prepared tellurium nanosheets as the saturable absorber (SA), we realized a passively $ Q $Q-switched ${\rm Nd} \text:{{\rm YVO}_4}$Nd:YVO4 laser operating at 1342 nm with a pulse width of 947 ns and single pulse energy of 2.25 µJ. Our work indicated the tellurium SA could be an efficient $ Q $Q-switcher for a near-infrared solid-state laser.

13.
Opt Lett ; 44(2): 451-454, 2019 Jan 15.
Article in English | MEDLINE | ID: mdl-30644923

ABSTRACT

In this Letter, a high-quality saturable absorber (SA) based on a multilayered two-dimensional ternary chalcogenide Ta2NiS5 with a narrow bandgap, has been successfully fabricated and used as a SA in a 1.9 µm spectral region. The nonlinear saturable absorption properties of the as-prepared SA have been investigated by using an open-aperture Z-scan method. A passively Q-switched all-solid-state laser operating at 1.9 µm has been realized with the Ta2NiS5 SA. The maximum average output power, shortest pulse width, pulse energy, and pulse peak power from the passively Q-switched (PQS) laser are 1.1 W, 313 ns, 22.0 µJ, and 71.0 W, respectively. This is the first demonstration of the saturable absorption property of Ta2NiS5, to the best of our knowledge. The results indicate well the promising potential of Ta2NiS5 as a broadband SA in realizing pulsed mid-infrared lasers with high performance.

14.
Nanoscale ; 10(43): 20171-20177, 2018 Nov 08.
Article in English | MEDLINE | ID: mdl-30229783

ABSTRACT

1T-titanium selenide (1T-TiSe2), a representative of 1T phase transition metal dichalcogenides (TMDs), exhibits semimetallic behaviour with a nearly zero bandgap structure, which makes it a promising photoelectric material. A high-quality multilayer 1T-TiSe2 saturable absorber (SA) is successfully fabricated by a combination of liquid phase exfoliation and the spin coating method. The broadband nonlinear saturable absorption properties of the prepared 1T-TiSe2 SA are investigated by using the open aperture (OA) Z-scan method. Passively Q-switched (PQS) all-solid-state lasers with different bulk crystals at the wavelengths of 1.0, 1.3, 2.0 and 2.8 µm are realised based on the 1T-TiSe2 SA. To the best of our knowledge, this is the first presentation of the application of a 1T-TiSe2 material to all-solid-state bulk lasers. The results indicate that 1T-TiSe2 could be an alternative broadband SA for solid-state pulsed lasers and exhibits promising potential applications in mode-locked ultrafast lasers.

15.
Opt Express ; 26(14): 18505-18512, 2018 Jul 09.
Article in English | MEDLINE | ID: mdl-30114029

ABSTRACT

In this article, a high-power diode-end-pumped passively Q-switched (PQS) Tm:YAP laser is reported with novel two-dimension (2D) molybdenum ditelluride (MoTe2) as a saturable absorber (SA). By using the open-aperture Z-scan method, the saturable absorption properties around 2.0 µm was characterized with a saturable fluence of 2.26 µJ∕cm2 and a modulation depth of 6.0% for the as-prepared MoTe2 SA. The band structure of MoTe2 with the introduction of Te vacancies is simulated by the DFT method, and the results indicate that the bandgap can be reduced with the vacancies in a suitable range. The shortest pulse width of 380 ns was obtained with an average output power of 1.21 W at a repetition rate of 144 kHz, corresponding to a maximum single pulse energy of 8.4 µJ and peak power of 22.2 W. It is the first presentation of MoTe2 as the saturable absorber in 2.0 µm solid-state pulse laser generation and the pulse width is the shortest among 2.0 µm solid-state lasers passive Q-switched with transitional metal dichalcogenides (TMDs) SAs to the best of our knowledge. The results indicated that MoTe2 should be an excellent optical modulator for high repetition rate and short pulsed laser generation in a broadband spectral range.

16.
Opt Lett ; 43(16): 3862-3865, 2018 Aug 15.
Article in English | MEDLINE | ID: mdl-30106902

ABSTRACT

Few-layered titanium carbide (Ti3C2Tx), a novel two-dimensional (2D) Van der Waals material in the MXene family, was fabricated with a liquid-phase method and applied as a saturable absorber for a continuous-wave mode-locked femtosecond bulk laser. Pulses as short as 316 fs with a repetition rate of 64.06 MHz and maximum output power of 0.77 W were achieved at the central wavelength of 1053.2 nm, demonstrating the first known, to the best of our knowledge, application of MXene in an all-solid-state laser. Considering the flexible band gap for different surface functional groups of Ti3C2Tx, these results may promote the development of ultrafast photonics and further applications of 2D optoelectronic layered materials in the infrared and mid-infrared regions.

17.
Opt Lett ; 43(14): 3349-3352, 2018 Jul 15.
Article in English | MEDLINE | ID: mdl-30004503

ABSTRACT

1T-phase titanium diselenide (1T-TiSe2), a model two-dimensional (2D) transition metal dichalcogenide, has attracted much attention due to its intriguing electrical and optical properties. In this work, a 1T-TiSe2-based high-quality large-area saturable absorber (SA) (1T-TiSe2-SA) was successfully fabricated with the liquid-phase exfoliation method. With the as-prepared 1T-TiSe2-SA, a stable, passively Q-switched laser operating at 2.95 µm was first realized. Under an absorbed pump power of 3.35 W, the maximum average output power was 130 mW with a slope efficiency of 5%. A pulse width of 160.5 ns was obtained, which is the shortest among 3.0 µm passively Q-switched lasers ever achieved with 2D materials as SAs, to the best of our knowledge. The results indicate that 1T-TiSe2 is a promising alternative as a nonlinear optical modulator for short-pulse laser generation near the 3.0 µm mid-infrared region.

18.
Opt Express ; 26(24): 31657-31663, 2018 Nov 26.
Article in English | MEDLINE | ID: mdl-30650749

ABSTRACT

A noble transition metal dichalcogenide, bilayers platinum diselenide (PtSe2), has a narrow bandgap (0.21 eV) and high charge carrier mobility. This metal was manufactured for use as a saturable absorber via the chemical vapor deposition method. The saturable absorption properties of samples, at a wavelength of 2.0 µm, were characterized by the open aperture Z-scan method. An all-solid-state 2.0 µm passively Q-switched laser was achieved experimentally based on the as-prepared bilayers PtSe2 saturable absorber. The maximum average output power, shortest pulse width, highest single-pulse energy, and highest pulse peak power of this laser were 1.41 W, 244 ns, 24.3 µJ, and 99.6 W, respectively.

19.
Opt Lett ; 42(17): 3502-3505, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28957073

ABSTRACT

A novel two-dimensional (2D) material member in the transition metal dichalcogenides family, few-layered rhenium disulfide (ReS2) was prepared by liquid phase method successfully. By using the open-aperture Z-scan method, the saturable absorption properties at 2.8 µm were characterized with a saturable fluence of 22.6 µJ/cm2 and a modulation depth of 9.7%. A passively Q-switched solid-state laser at 2.8 µm was demonstrated by using the as-prepared ReS2 saturable absorber successfully. Under an absorbed pump power of 920 mW, a maximum output power of 104 mW was obtained with a pulse width of 324 ns and a repetition rate of 126 kHz. To the best of our knowledge, this is the first demonstration of applying ReS2 in an all-solid-state laser. Moreover, this represents the shortest pulses in Q-switched MIR lasers based on a 2D material as the saturable absorber, which demonstrated the superiority of ReS2 acting as an optical modulator for generating short-pulsed lasers. The results well prove that 2D ReS2 is a reliable optical modulator for MIR solid-state lasers.

20.
Oncotarget ; 8(23): 37321-37331, 2017 Jun 06.
Article in English | MEDLINE | ID: mdl-28418879

ABSTRACT

It has been well established that microRNAs (miRNAs) play important roles in biological processes. To comprehensively measure the altered miRNA expression, we presented the miRNA expression profile of gastric cancer using microarray. We identified 33 miRNAs that were significantly differentially regulated in gastric specimens compared to adjacent normal tissues, among which miR-9-3p expression are significantly down-regulated in gastric cancers. Next, a cohort of 100 gastric cancer tissues and matched normal tissues were enrolled. Kaplan-Meier and multivariate Cox survival analyses were applied to evaluate the prognostic value of miR-9-3p expression, and the result showed that patients with lower miR-9-3p expression level have significantly poorer overall survival. The expression level of miR-9-3p has been proved to be an independent prognostic factor for 5-year overall survival. Furthermore, the result indicated that over-expression of miR-9-3p can inhibit gastric cancer cell invasion. Taken together, our results suggested that miR-9-3p plays important role in tumor invasion, and these findings implicated the potential effects of miR-9-3p on prognosis of gastric cancer.


Subject(s)
MicroRNAs/genetics , Stomach Neoplasms/genetics , Stomach/physiology , Cell Line, Tumor , Cell Proliferation , Cohort Studies , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , Humans , Male , Middle Aged , Prognosis , Stomach Neoplasms/diagnosis , Stomach Neoplasms/mortality , Survival Analysis
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