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1.
Appl Opt ; 63(3): 865-873, 2024 Jan 20.
Article in English | MEDLINE | ID: mdl-38294403

ABSTRACT

In this paper, a high-quality germanene-polyvinyl alcohol (PVA) saturable absorber (SA) with a modulation depth of 3.05% and a saturation intensity of 17.95M W/c m 2 was prepared. Stable conventional mode-locking and harmonic mode-locking (HML) were achieved in germanene-based Er-doped fiber lasers (EDFL) using dispersion management techniques. In a cavity with a net dispersion value of -0.22p s 2, the conventional soliton had a center wavelength of 1558.2 nm, a repetition frequency of 19.09 MHz, and a maximum 3 dB spectrum bandwidth of 3.5 nm. The highest repetition frequencies achieved in cavities with net dispersion values of -2.81p s 2, -1.73p s 2, and -1.09p s 2 were 9.48 MHz, 12.75 MHz, and 12.10 MHz for HML, respectively. Furthermore, the effects of dispersion, power, and the polarization state on HML were systematically investigated. Our research results fully demonstrate the capability of germanene as an optical modulator in generating conventional mode-locked and harmonic mode-locked solitons. This provides meaningful references for promoting its application in ultrafast fiber lasers.

2.
Opt Express ; 31(6): 10176-10190, 2023 Mar 13.
Article in English | MEDLINE | ID: mdl-37157571

ABSTRACT

With the advances in the field of ultrafast photonics occurring so fast, the demand for optical modulation devices with high performance and soliton lasers which can realize the evolution of multiple soliton pulses is gradually increasing. Nevertheless, saturable absorbers (SAs) with appropriate parameters and pulsed fiber lasers which can output abundant mode-locking states still need to be further explored. Due to the special band gap energy values of few-layer indium selenide (InSe) nanosheets, we have prepared a SA based on InSe on a microfiber by optical deposition. In addition, we demonstrate that our prepared SA possesses a modulation depth and saturable absorption intensity about 6.87% and 15.83 MW/cm2, respectively. Then, multiple soliton states are obtained by dispersion management techniques, including regular solitons, and second-order harmonic mode-locking solitons. Meanwhile, we have obtained multi-pulse bound state solitons. We also provide theoretical basis for the existence of these solitons. The results of the experiment show that the InSe has the potential to be an excellent optical modulator because of its excellent saturable absorption properties. This work also is important for improving the understanding and knowledge of InSe and the output performance of fiber lasers.

3.
Nanomaterials (Basel) ; 13(6)2023 Mar 14.
Article in English | MEDLINE | ID: mdl-36985932

ABSTRACT

Abundant research findings have proved the value of two-dimensional (2D) materials in the study of nonlinear optics in fiber lasers. However, there remains two problems: how to reduce the start-up threshold, and how to improve the damage threshold, of fiber lasers based on 2D materials. A 15.1 mW low-threshold mode-locked fiber laser, based on a Cr2Si2Te6 saturable absorber (SA) prepared by the liquid-phase exfoliation method, is demonstrated successfully in this work. This provides a useful and economical method to produce SAs with low insertion loss and low saturation intensity. Besides, multiple high-order harmonics, from the fundamental frequency (12.6 MHz) to the 49th-order harmonic (617.6 MHz), mode-locked operations are recorded. The experimental results indicate the excellent potential of Cr2Si2Te6 as an optical modulator in exploring the soliton dynamics, harmonic mode locking, and other nonlinear effects in fiber lasers.

4.
Anim Biotechnol ; 34(7): 2817-2826, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36093624

ABSTRACT

Existing experiments have found a new intergenic lncRNA activated by melatonin, which is called lncRNA MTC. However, the regulatory mechanism of lncRNA MTC in Liaoning Cashmere goat skin fibroblasts has not been clarified. Specific knockdown of lncRNA MTC inhibits cell proliferation and increases apoptosis. iTRAQ reagent was used for relative and absolute quantification of proteins in lncRNA MTC-KD and NC groups to evaluate changes in protein expression during dermal fibroblast development following lncRNA MTC deletion. A total of 5931 proteins were found in Liaoning Cashmere goat skin fibroblasts, of which 123 were differentially expressed, including 32 up-regulated proteins and 91 down-regulated proteins. Of the 91 down-regulated proteins, 32 act mainly through related pathways (e.g., cell cycle, mitochondrial function, ribosomal structure, vesicular transport, cytoskeletal components and skin morphogenesis). LncRNA MTC facilitates the proliferation of Liaoning Cashmere goat skin fibroblasts by regulating ITGB5, TlN2, CTSS, POLG, RAP1B, CHAF1A, CDCA8 and other proteins involved in cell proliferation. The results of this study provide some candidate proteins for the in-depth investigation of the molecular mechanism of lncRNA MTC, which facilitates hair growth in cashmere goats and provides more insights into their regulatory networks and biochemical pathways.


Subject(s)
RNA, Long Noncoding , Animals , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Hair Follicle/metabolism , Goats , Fibroblasts
5.
Materials (Basel) ; 15(15)2022 Aug 08.
Article in English | MEDLINE | ID: mdl-35955391

ABSTRACT

This study aims to comprehensively investigate the rejuvenation efficiency of various self-developed compound rejuvenators on the physical, mechanical, and aging properties of aged bitumen, asphalt mortar, and mixture. The results revealed that the restoration capacity of vacuum distilled-oil rejuvenators on high-and-low temperature performance-grade of aged bitumen is more significant. In contrast, an aromatic-oil based rejuvenator is good at enhancing low-temperature grade and aging resistance. Moreover, the temperature and time of the curing conditions for mixing recycling of asphalt mixture were optimized as 150 °C and 120 min. Furthermore, the sufficient anti-rutting, structural stability, and moisture resistance of recycled asphalt mixture affirmed the rejuvenation efficiency of compound rejuvenators.

6.
Appl Opt ; 61(11): 3254-3259, 2022 Apr 10.
Article in English | MEDLINE | ID: mdl-35471305

ABSTRACT

In this work, a saturable absorber (SA) based on Cr2Si2Te6 (CST), with a modulation depth of 14.90% and saturation intensity of 4.81MW/cm2, was prepared by a liquid phase stripping method. Its nonlinear optical properties and application in obtaining mode-locked pulse output of bright-dark solitons are studied. When the pump power was 1250 mW, the maximum output power was 26.60 mW; the energy of the single pulse was 15.02 nJ, and the repetition rate was 1.77 MHz. Our results provided evidence that CST can be used as an excellent SA for a mode-locked laser and demonstrated that ferromagnetic insulators can be used for the study of bright-dark soliton pairs.

7.
J Org Chem ; 87(1): 835-845, 2022 01 07.
Article in English | MEDLINE | ID: mdl-34962788

ABSTRACT

An efficient method for the synthesis of new indolizine-fused chromones has been accomplished from ethyl (E)-3-(2-acetylphenoxy)acrylates and pyridines in a "one-pot" manner. Facile operation in open-air, metal-free, and mild conditions renders this protocol particularly practical and attractive. Moreover, this method can simultaneously construct two molecular fragments of chromone and indolizine. Scale-up experiment and the construction of natural products further prove the practicability of this strategy.


Subject(s)
Indolizines , Iodine , Chromones , Cyclization , Pyridines
8.
Materials (Basel) ; 14(9)2021 May 10.
Article in English | MEDLINE | ID: mdl-34068488

ABSTRACT

High production costs and poor storage stability have become important constraints in the manufacture of modified asphalt binder. To simplify the production process and reduce the production cost, amorphous poly alpha olefin (APAO) and polyphosphoric acid (PPA) were applied to prepare highly stable modified asphalt binder. The influence of APAO/PPA on the temperature sensitivity, rheological property, storage stability, compatibility and microstructure of neat binder were studied by rotational viscosity (RV), dynamic shear rheometer (DSR), bending beam rheometer (BBR) and Fourier transform infrared (FTIR) spectroscopy. The results show that the incorporation of APAO/PPA reduced the temperature sensitivity of neat binder. The combined effect of APAO/PPA contributed to the improvement in deformation resistance, which was evidenced by the increase in failure temperature and percent recovery. However, the compound modification of APAO/PPA decreased the binder's low-temperature performance. APAO strengthened the fatigue resistance of the binder, while PPA reduced the anti-fatigue performance. Composite modified asphalt binder with superior storage stability could be prepared, which was confirmed by the desired Cole-Cole plots and fluorescence imaging. Furthermore, chemical and physical reactions occurred during the APAO/PPA modification process. Overall, 2 wt.% (weight percentage) APAO and 1.5 wt.% PPA are recommended for the production of modified asphalt binder with remarkable rheological performance and storage stability.

9.
Materials (Basel) ; 14(4)2021 Feb 08.
Article in English | MEDLINE | ID: mdl-33567546

ABSTRACT

Oil sands de-oiled asphalt (OSDOA) has become a bottleneck for refineries due to its enormous production and huge landfill costs. Applying OSDOA as a modifier is an effective way to reduce environmental pollution and disposal cost. In this study, the influences of OSDOA and polyphosphoric acid (PPA) compound modification on styrene-butadiene-styrene (SBS)-modified binder were investigated. The high-temperature rutting resistance, low-temperature anti-crack performance and fatigue resistance were obtained by dynamic shear rheometer (DSR) and bending beam rheometer (BBR) test. Storage stability and microstructure were also investigated by storage test and Fourier-transform infrared (FTIR) spectroscopy. The results demonstrated that the compound modification of OSDOA/PPA dramatically enhanced the deformation resistance of SBS-modified binder and reduced its low-temperature cracking resistance. The anti-fatigue performance was also decreased. Moreover, the combined effect of OSDOA and PPA could produce composite modified asphalt with excellent storage stability, which was verified by desirable fluorescence images. Furthermore, both physical and chemical interactions coexisted during the OSDOA/PPA compound modification process. Consequently, the optimal doses of OSDOA and PPA were determined to be 10 wt% and 1.0 wt%, considering of the balance between high- and low-temperature characteristics and storage stability of composite modified asphalt.

10.
Materials (Basel) ; 12(22)2019 Nov 08.
Article in English | MEDLINE | ID: mdl-31717293

ABSTRACT

A styrene-butadiene-styrene (SBS) latex modifier can be used for asphalt modification due to the fact of its energy-saving, construction convenience, and economic advantages. The objective of this study was to investigate the influence of asphalt type and SBS latex dosage on the rheological properties, compatibility, and storage stability of asphalt through temperature and frequency sweep, steady-state flow, multiple stress creep and recovery (MSCR) tests, Cole-Cole plots and thermal storage tests. The results indicated that high SBS latex content is beneficial for improving anti-rutting, anti-fatigue, viscous flow resistance, and elastic recovery abilities of modified asphalt. The chemical composition of asphalt had a significant effect on the properties of the SBS latex-modified asphalt. High asphaltenes and low resins were favorable to enhancing anti-rutting and recovery properties but weakened the anti-fatigue, compatibility, and storage stability of modified asphalt. Furthermore, compared to SBS particle-modified asphalt, SBS latex-modified asphalt had greater rutting and fatigue resistance. However, SBS latex-modified asphalt had some disadvantages in compatibility and storage stability. Comprehensively considering the balance of viscoelastic properties, compatibility, and storage stability of SBS latex-modified asphalt, the mixing dosage of SBS latex modifier is recommended at 4.0 wt% which could feasibly replace SBS particle in asphalt modification.

11.
Angew Chem Int Ed Engl ; 54(22): 6540-4, 2015 May 26.
Article in English | MEDLINE | ID: mdl-25881689

ABSTRACT

The broadband light-absorption ability of carbon dots (CDs) has inspired their application in photocatalysis, however this has been impeded by poor electron transfer inside the CDs. Herein, we report the preparation of Cu-N-doped CDs (Cu-CDs) and investigate both the doping-promoted electron transfer and the performance of the CDs in photooxidation reactions. The Cu-N doping was achieved through a one-step pyrolytic synthesis of CDs with Na2 [Cu(EDTA)] as precursor. As confirmed by ESR, FTIR, and X-ray photoelectron spectroscopies, the Cu species chelates with the carbon matrix through Cu-N complexes. As a result of the Cu-N doping, the electron-accepting and -donating abilities were enhanced 2.5 and 1.5 times, and the electric conductivity was also increased to 171.8 µs cm(-1) . As a result of these enhanced properties, the photocatalytic efficiency of CDs in the photooxidation reaction of 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate is improved 3.5-fold after CD doping.


Subject(s)
Copper/chemistry , Quantum Dots/chemistry , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Electron Spin Resonance Spectroscopy , Electron Transport , Light , Nitrogen/chemistry , Oxidation-Reduction , Photoelectron Spectroscopy , Spectrophotometry, Ultraviolet
12.
Bioresour Technol ; 140: 337-41, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23708846

ABSTRACT

Preparation of biodiesel from vegetable oils, such as rapeseed oil, soybean oil and sunflower oil, catalyzed by an alkaline ionic liquid 1-butyl-3-methylimidazolium imidazolide ([Bmim]Im) was investigated in this work. The results demonstrated that [Bmim]Im exhibited high activity and the yield of biodiesel was up to 95% or more when molar ratio of methanol to vegetable oil was 6:1, ionic liquid dosage was 6 wt.%, reaction temperature was 60°C, and reaction time was 60 min. After [Bmim]Im was used for the sixth time, the yield of biodiesel still remained at about 95%. The effects of the biodiesels on the lubricity of low-sulfur diesel fuel were also investigated using the High Frequency Reciprocating Rig method, and the results showed that sunflower biodiesel and soybean biodiesel had higher lubrication performance than that of rapeseed biodiesel.


Subject(s)
Alkalies/chemistry , Biofuels , Biotechnology/methods , Gasoline , Ionic Liquids/chemistry , Lubrication , Sulfur/chemistry , Fatty Acids/analysis , Fatty Acids, Monounsaturated , Imidazoles/chemistry , Methanol/chemistry , Plant Oils/chemistry , Rapeseed Oil , Soybean Oil/chemistry , Sunflower Oil , Temperature , Time Factors
13.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 32(6): 846-8, 2012 Jun.
Article in Chinese | MEDLINE | ID: mdl-22978119

ABSTRACT

With the significant and continuous growth of the research and application of complementary and alternative medicine (CAM) all over the world, the demand for medical information services has been increasing correspondingly. However, the barriers of accessing and utilizing non-English literature, and the barrier of language have blocked English speaking clinicians and researchers of CAM from obtaining high quality and authoritative medical evidence from the non-English medical resources. This article, with introducing the UCLA Information Center for East-West Integrative Medicine, will demonstrate a new collaborative mode of integrative medicine information service between China and the US, and discuss the perceived challenges.


Subject(s)
Complementary Therapies , Information Services , Integrative Medicine , China , Information Storage and Retrieval , Language , United States
14.
J Altern Complement Med ; 14(5): 595-609, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18554083

ABSTRACT

BACKGROUND: Traditional Chinese Medical (TCM) journals have been playing an important role in scholarly communication in China. However, the information in those periodicals was not enough for international readers. OBJECTIVE: This study aims to provide an overview of TCM journals in China. METHODS: TCM journals currently published in mainland China were identified from Chinese databases and journal subscription catalogs. Data on publication start year, publishing region, language, whether core journals, whether indexed in famous international databases, with/without accessible URL were investigated, and subjects of journals were categorized. RESULTS: One hundred and forty-nine (149) TCM journals are currently published in mainland China; 88.59% of them are academic journals. The subjects of those journals are various, ranging from the general TCM, integrative medicine, herbal medicines, to veterinary TCM. The publishing areas are distributed in 27 regions, with Beijing having the most TCM journals published. One hundred and forty-two (142) of those periodicals are in Chinese, while 4 are also in English, and 3 in other languages. Only 8 TCM journals were recognized as core journals, and 5 were identified as both core journals and journals with high impacted articles by all evaluation systems in China. A few of the TCM journals from mainland China are indexed in PubMed/MEDLINE (10), EMBASE (5), Biological Abstracts (2), or AMED (1). Online full-text Chinese databases CJFD, COJ, and CSTPD cover most of TCM the journals published in the country. One hundred (100) TCM journals have accessible URLs, but only 3 are open access with free full texts. CONCLUSIONS: Publication of TCM journals in China has been active in academic communication in the past 20 years. However, only a few of them received recognized high evaluation. English information from them is not sufficient. Open access is not extensively acceptable. The accessibility of those journals to international readers needs to be improved.


Subject(s)
Bibliometrics , Databases, Bibliographic/statistics & numerical data , Medicine, Chinese Traditional , Periodicals as Topic/statistics & numerical data , Publishing/statistics & numerical data , China , Humans , Information Storage and Retrieval , Peer Review, Research , Societies, Medical/organization & administration
15.
Artif Intell Med ; 38(3): 219-36, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16930966

ABSTRACT

OBJECTIVE: As a complementary medical system to Western medicine, traditional Chinese medicine (TCM) provides a unique theoretical and practical approach to the treatment of diseases over thousands of years. Confronted with the increasing popularity of TCM and the huge volume of TCM data, historically accumulated and recently obtained, there is an urgent need to explore these resources effectively by the techniques of knowledge discovery in database (KDD). This paper aims at providing an overview of recent KDD studies in TCM field. METHODS: A literature search was conducted in both English and Chinese publications, and major studies of knowledge discovery in TCM (KDTCM) reported in these materials were identified. Based on an introduction to the state of the art of TCM data resources, a review of four subfields of KDTCM research was presented, including KDD for the research of Chinese medical formula, KDD for the research of Chinese herbal medicine, KDD for TCM syndrome research, and KDD for TCM clinical diagnosis. Furthermore, the current state and main problems in each subfield were summarized based on a discussion of existing studies, and future directions for each subfield were also proposed accordingly. RESULTS: A series of KDD methods are used in existing KDTCM researches, ranging from conventional frequent itemset mining to state of the art latent structure model. Considerable interesting discoveries are obtained by these methods, such as novel TCM paired drugs discovered by frequent itemset analysis, functional community of related genes discovered under syndrome perspective by text mining, the high proportion of toxic plants in the botanical family Ranunculaceae disclosed by statistical analysis, the association between M-cholinoceptor blocking drug and Solanaceae revealed by association rule mining, etc. It is particularly inspiring to see some studies connecting TCM with biomedicine, which provide a novel top-down view for functional genomics research. However, further developments of KDD methods are still expected to better adapt to the features of TCM. CONCLUSIONS: Existing studies demonstrate that KDTCM is effective in obtaining medical discoveries. However, much more work needs to be done in order to discover real diamonds from TCM domain. The usage and development of KDTCM in the future will substantially contribute to the TCM community, as well as modern life science.


Subject(s)
Knowledge , Medicine, Chinese Traditional/methods , Research , Databases, Factual , Humans , Syndrome
16.
J Clin Oncol ; 24(3): 419-30, 2006 Jan 20.
Article in English | MEDLINE | ID: mdl-16421421

ABSTRACT

PURPOSE: Systemic treatments for advanced non-small-cell lung cancer have low efficacy and high toxicity. Some Chinese herbal medicines have been reported to increase chemotherapy efficacy and reduce toxicity. In particular, Astragalus has been shown to have immunologic benefits by stimulating macrophage and natural killer cell activity and inhibiting T-helper cell type 2 cytokines. Many published studies have assessed the use of Astragalus and other Chinese herbal medicines in combination with chemotherapy. We sought to evaluate evidence from randomized trials that Astragalus-based Chinese herbal medicine combined with platinum-based chemotherapy (versus platinum-based chemotherapy alone) improves survival, increases tumor response, improves performance status, or reduces chemotherapy toxicity. METHODS: We searched CBM, MEDLINE, TCMLARS, EMBASE, Cochrane Library, and CCRCT databases for studies in any language. We grouped studies using the same herbal combinations for random-effects meta-analysis. RESULTS: Of 1,305 potentially relevant publications, 34 randomized studies representing 2,815 patients met inclusion criteria. Twelve studies (n = 940 patients) reported reduced risk of death at 12 months (risk ratio [RR] = 0.67; 95% CI, 0.52 to 0.87). Thirty studies (n = 2,472) reported improved tumor response data (RR = 1.34; 95% CI, 1.24 to 1.46). In subgroup analyses, Jin Fu Kang in two studies (n = 221 patients) reduced risk of death at 24 months (RR = 0.58; 95% CI, 0.49 to 0.68) and in three studies (n = 411) increased tumor response (RR = 1.76; 95% CI, 1.23 to 2.53). Ai Di injection (four studies; n = 257) stabilized or improved Karnofsky performance status (RR = 1.28; 95% CI, 1.12 to 1.46). CONCLUSION: Astragalus-based Chinese herbal medicine may increase effectiveness of platinum-based chemotherapy when combined with chemotherapy. These results require confirmation with rigorously controlled trials.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Astragalus Plant , Carcinoma, Non-Small-Cell Lung/drug therapy , Drugs, Chinese Herbal/therapeutic use , Lung Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cisplatin/administration & dosage , Humans , Phytotherapy/methods , Randomized Controlled Trials as Topic , Survival Analysis , Treatment Outcome
17.
Artif Intell Med ; 32(1): 15-27, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15350621

ABSTRACT

Traditional Chinese medicine (TCM) as a complete knowledge system researches into human health conditions via a different approach compared to orthodox medicine. We are developing a unified traditional Chinese medical language system (UTCMLS) through an ontology approach that will support TCM language knowledge storage, concept-based information retrieval and information integration. UTCMLS is a huge knowledge project, which is a broad collaboration of 16 distributed groups, most of them with no prior experience of formal ontology development. Therefore, the cooperative and comprehensive ontology engineering is crucial. We use Protégé 2000 for ontology development of concepts and relationships that represent the domain and that will permit storage of TCM knowledge. This paper focuses on the methodology, design and development of ontology for UTCMLS.


Subject(s)
Medicine, Chinese Traditional , Unified Medical Language System , Humans , Information Storage and Retrieval
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