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1.
Phys Chem Chem Phys ; 25(9): 7047, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36794492

RESUMO

Correction for 'Liquid crystal random lasers' by Guangyin Qu et al., Phys. Chem. Chem. Phys., 2023, 25, 48-63, https://doi.org/10.1039/D2CP02859J.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 286: 121959, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36252302

RESUMO

This study demonstrates a mobile passive differential optical absorption spectroscopy (DOAS) based remote sensing method for quantifying the emission fluxes of soot pollutants. First, the mobile DOAS system scans the plume emitted from urban sources. Then, the DOAS method retrieves the total columns of pollutant gases along the measurement path. Combining the longitude, latitude, and mobile speed recorded by vehicle GPS, the net emission fluxes of NO2 and SO2 in the measurement area are calculated by coupling with the wind field data. The NO2 flux in the region is combined with the NO to NO2 concentration ratio in the Copernicus Atmospheric Monitoring Service (CAMS) model to calculate NOx net emission flux in the measurement period. We conducted the mobile DOAS measurements in the coal production area and obtained the distribution of pollutant gases along the measurement path. Meanwhile, the NO2 concentration distribution of the city and surrounding areas were reconstructed by using TROPOMI satellite data. During the mobile measurement, the net NO2 emission flux measured by mobile DOAS are in good agreement with satellite observations (R2 = 0.66). This study verified that the flux calculation method based on mobile DOAS can be used to detect urban soot pollutant gas emissions.

3.
J Ethnopharmacol ; 303: 116002, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36509253

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Albizia julibrissin Durazz is a well-known medicinal plant with the Chinese name Hehuan []. Hehuan bark and Hehuan flowers have long been recognized as traditional Chinese herbal medicine for treating anxiety, melancholy, insomnia, bruises, pulmonary abscess, fractures, carbuncle, amnesia, acute conjunctivitis, blurred vision, neonatal tetanus and stroke for thousands of years. They are recorded in Chinese Pharmacopoeia separately with different properties. Until now, new chemical constituents and pharmacological activities of Hehuan have been continuously studied and revealed. THE AIM OF THE REVIEW: This review aims to provide a comprehensive summary of traditional applications, phytochemistry, pharmacology effects, and toxicology of Hehuan bark and Hehuan flowers, and give critical assessment and point out the promising direction for further research on Hehuan. MATERIAL AND METHODS: A literature search was undertaken on Hehuan bark and Hehuan flowers by analyzing the information from scientific databases (SciFinder, Pubmed, Elsevier, Google Scholar, Web of Science, and Baidu Scholar). We also gathered the information of Hehuan from classic herbal literatures and conference papers on ethnopharmacology. RESULTS: According to Chinese and English documents, the medicinal history of Hehuan in China can be traced back to ad 25. Meanwhile, its medicinal history as a kind of herbal medicine can also be found in other Asian countries. So far about 140 compounds have been isolated from Hehuan bark and Hehuan flowers, including triterpenoids, flavonoids, lignans, phenolic acids, alkaloids, etc. Among them, flavonoids mainly exist in Hehuan flowers, while Hehuan bark contains lignans and saponins. The composition differences between the barks and flowers of Hehuan account for the different effects and applications. Modern pharmacological studies have indicated that crude extracts and pure compounds of Hehuan flowers and Hehuan bark have multiple pharmacological activities, such as antineoplastic, immunomodulatory, anti-inflammatory, anxiolytic, antidepressant, metabolic regulation, anti-insomnia, neuroprotective, hepatoprotective, sedative, and anti-osteolytic activities. CONCLUSIONS: Hehuan (Albizia julibrissin Durazz) is traditionally used to relieve depression, calm nerves, promote blood circulation and reduce swelling. Modern pharmacological studies have revealed that natural products from Hehuan bark and Hehuan flowers possess extensive pharmacological activities in treating cancer, enhancing immunity, regulating metabolism, improving mental state, etc. These properties make it great clinical application potential. Further research on natural pharmaceutical chemistry, pharmacology, toxicology, pharmacokinetics, and quality standards of Hehuan are still required to verify the efficacy and safety for future clinical applications.


Assuntos
Medicamentos de Ervas Chinesas , Lignanas , Plantas Medicinais , Casca de Planta , Etnofarmacologia , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/farmacologia , Flores , Flavonoides , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química
4.
Phys Chem Chem Phys ; 25(1): 48-63, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36477742

RESUMO

The enthusiasm for research on liquid crystal random lasers (LCRLs) is driven by their unusual optical properties and promising potential for broad applications in manufacturing, communications, medicine and entertainment. From this perspective, we will summarize the most attractive advances in the development of LCRLs in the last decade and propose future prospects. This article will begin with a fundamental description of LCRLs, including the principle of laser generation and a description of LC substances. Then, we spend several chapters on the lasing performance control methods of LCRLs, including random lasing wavelength, threshold, and polarization properties. In addition, we analyze how the LC chiral agent structures, LC core-shell structures and new light-amplifying materials affect the design of LCRL devices. In the last chapter, we discuss the application of LCRLs in 3D displays, information encryption, biochemical sensing and other optoelectronics devices and finally end the perspective with LCRLs' likely directions in future research.


Assuntos
Cristais Líquidos , Cristais Líquidos/química , Desenho de Equipamento , Lasers , Luz
5.
Soft Matter ; 18(46): 8840-8849, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36373235

RESUMO

We investigate three azo-chromophore-containing photoswitches (1, 2 and 3) for molecular solar thermal storage (MOST) based on reversible Z-E isomerization. 1, 2 and 3 are photoswitchable compounds that contain one, two and three azo chromophores, respectively. In solution, 1, 2 and 3 were charged via UV-light-induced E-to-Z isomerization. Among these three compounds, 2 exhibited an energy density as high as 272 ± 1.8 J g-1, which showed the best energy storage performance. This result originated from the low molecular weight, a high degree of photoisomerization, and moderate steric hindrance of 2, which demonstrated the advantages of the meta-bisazobenzene structure for MOST. In addition, we studied the performances of these photoswitches in the solvent-free state. Only 1 showed photoinduced reversible solid-to-liquid transitions, which enabled the charging of 1 in a solvent-free state. The stored energy density for 1 in a solvent-free state was 237 ± 1.5 J g-1. By contrast, 2 and 3 could not be charged in the solvent-free state due to the lack of solid-state photoisomerization. Our findings provide a better understanding of the structure-performance relationship for azobenzenebased MOST and pave the way for the development of high-density solar thermal fuels.

6.
Macromol Rapid Commun ; 43(4): e2100703, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35038195

RESUMO

Photoresponsive polymer gels have attracted increasing interest owing to their potential applications in healable materials, drug release systems, and extracellular matrices. Because polymer gels provide suitable environments for photochemical reactions, their properties and functions can be controlled with light with a high spatiotemporal resolution. Herein, the design of photoresponsive polymer gels based on different types of photochemical reactions is introduced. The mechanism and applications of irreversible photoreactions, such as photoinduced free-radical polymerization, photoinduced click reactions, and photolysis, as well as reversible photoreactions such as photoinduced reversible cycloadditions, reversible photosubstitution of metal complexes, and photoinduced metathesis are reviewed. The remaining challenges of photoresponsive polymer gels are also discussed.


Assuntos
Polímeros , Géis/química , Fotólise , Polimerização , Polímeros/química
7.
Soft Matter ; 16(22): 5203-5209, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32428056

RESUMO

Discotic π-conjugated supramolecular assemblies, especially with chiral supramolecular nanostructures, have been attracting growing research interest due to their significant optoelectronic properties and the possibilities of their applications in the new generation of organic semiconductors. However, the impact of supramolecular chirality on their mechanical and electrical performances remains poorly understood. Herein, a series of optically active supramolecular gels were formed from achiral triphenylene derivatives by introducing limonene as the chiral source. Owing to the well-ordered supramolecular packing, the homochiral supramolecular gels exhibited greater mechanical strength and higher conductivity, compared to heterochiral architectures. The impact of supramolecular packing in homochiral or heterochiral assemblies on their resulting mechanical and electrical performances was investigated in detail, which might be of great fundamental value for the rational design of chiral π-conjugated supramolecular nanostructures for applications in chiral optoelectronics.

8.
Chem Commun (Camb) ; 55(49): 7105-7108, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31157329

RESUMO

Here, we present a novel PDA microtube waveguide platform by combining heterogeneous CHA amplification with competitive inhibition. The heterogeneous CHA amplification system can preferentially amplify the signal of the correct target, while the competitive inhibition system will preferentially bind with the mutant targets and inactivate their signal.

9.
Nat Commun ; 10(1): 2093, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31048682

RESUMO

The original version of the Article contained an error in Figure 2 in which the TEM images in Fig. 2b and d were incorrect. Additionally, the seventh sentence of the 'Mechanism for the dissymmetry enhancement of SCL field' section of the Methods originally contained a mistake in the first equation. This has been corrected in both the PDF and HTML versions of the Article.

10.
Chem Commun (Camb) ; 55(34): 4953-4956, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30957827

RESUMO

Herein, we propose a novel circularly polarized light (CPL) triggered asymmetric self-assembly strategy to controllably construct chiral supramolecular assemblies from achiral porphyrin derivatives.

11.
ACS Appl Mater Interfaces ; 11(17): 15969-15976, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30964637

RESUMO

Programmable materials and reconfigurable photonic components, which can change their physicochemical properties and functionalities upon external stimuli, are a major topic of interest in modern science. However, most conventional reconfigurable photonic components rely heavily on mechanical deformation, restricting their application. Herein, a novel strategy based on a dynamically tunable fluorescence resonance energy transfer process to design and fabricate programmable fluorescent micropatterns within single polymer microfiber is proposed. A set of reconfigurable photonic components (including optical switchable waveguide systems, photonic analogies of diodes and transistors, as well as one-dimensional (1D) optical encoding) can be achieved within a single polymeric waveguide microfiber straightforwardly, in which such photonic components can be written, erased, and rewritten as 1D binary patterns with tailored external optical stimuli. These results might be of great fundamental value for the rational design of novel reconfigurable photonic devices with numerous potential applications in highly integrated optical communication components and optical computing devices.

12.
Soft Matter ; 15(9): 2051-2056, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30734816

RESUMO

Herein, we study the enantioselective cytotoxicity of vesicles self-assembled by optically active linear polymers (LNPs) and hyperbranched polymers (HBPs). Compared to HBP vesicles, LNP vesicles exhibit properties such as a higher surface charge density and more violent interaction with simulated biomembranes which results in larger cytotoxicity against HeLa cells. Specifically, racemic-LNP vesicles exhibit the largest cytotoxicity of all. More interestingly, there is no significant enantioselective dependence of HBP vesicles on the abovementioned properties. Overall, we proved that the cytotoxicity of vesicles is deeply related to chirality and topological-structures. This research is of great fundamental value for the design of novel bio-interface materials.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Polímeros/química , Polímeros/farmacologia , Células HeLa , Humanos , Fenômenos Ópticos , Espécies Reativas de Oxigênio/metabolismo , Estereoisomerismo , Propriedades de Superfície
13.
Biosens Bioelectron ; 129: 50-57, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30682689

RESUMO

Catalytic hairpin assembly (CHA) is a typical enzyme-free amplification strategy, in which the target can catalyze two hairpin probes to form a duplex and yield multiple outputs signal. However, the non-specific hybridization of two hairpin probes in CHA circuit usually occurred even in the absence of target, causing significant background leakage and impeding its practical applications in trace miRNA analysis. Herein, we proposed a novel heterogeneous CHA (hetero-CHA) design integrating with PDA microtube waveguide system, offering the advantages to enhance the target signal, but suppress the background leakage simultaneously. In hetero-CHA strategy, single-stranded targets are enriched nearby the surface of PDA microtube, facilitating the target-triggered CHA amplification and strand displacement reactions. In contrast, double-stranded DNA complexes formed by uncatalyzed hybridizations are isolated from PDA microtube, impeding the leakage signal. By combination with condensing enrichment effect, the proposed hetero-CHA probe exhibited high selectivity and sensitivity to miRNA target, giving a detection limit as low as 3.3 fM. More importantly, the proposed hetero-CHA probe can be applied directly to distinguish the expression of miRNA-21 in clinical serum of cancer patients (including lung, breast and pancreatic) from those of healthy human beings, favoring the cancer diagnosis and therapeutic evaluation.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , MicroRNAs/sangue , Polímero Poliacetilênico/química , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/sangue , Técnicas Biossensoriais/instrumentação , Humanos , Limite de Detecção , MicroRNAs/análise , Hibridização de Ácido Nucleico/métodos
14.
Nat Commun ; 9(1): 5117, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30504770

RESUMO

Superchiral light, generated by the interference of two counter-propagating circularly polarized light (CPL) with same frequency, opposite handedness and different intensity, exhibits enhanced dissymmetry in its interaction with chiral molecules, and has the potential for ultrasensitive detection and characterization of chiral molecules. It is anticipated that the enhanced optical dissymmetry in superchiral light (SCL) field may be utilized to promote asymmetric photochemical reactions efficiency. Herein we reported SCL impart greater chiral bias to trigger asymmetric photo-polymerization reaction from initially achiral diacetylene (DA) monomer, and the enhanced optical dissymmetry for whole polydiacetylene (PDA) films could be achieved. An explanation based on the chiral transfer and amplification of chiral bias from SCL during the polymerization process has been proposed. Moreover, thus formed chiral PDA films polymerized by SCL exhibited enhanced enantioselective recognition ability, and can serve as a direct visual probe for the discrimination of some specific enantiomers.

15.
Soft Matter ; 14(33): 6929-6937, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30101245

RESUMO

We demonstrate an easy and low-cost approach for the colorimetric differentiation of organic solvents using co-assemblies of polydiacetylenes (PDAs) and metal ions. The co-assemblies were prepared by the self-assembly of amphiphilic 10,12-tricosa diynoic acid with different metal ions (Zn2+, Cu2+, Ni2+, Ca2+) and subsequent photopolymerization. Different metal ions underwent different interactions with the carboxyl groups on the side chains of poly(10,12-tricosa diynoic acid), which influenced the stimuli-responsiveness of the PDA/metal ion co-assemblies. As a result, the PDA/metal ion co-assemblies with different metal ions showed different solvatochromism. Based on this property, the co-assemblies were used as sensors to differentiate organic solvents.

16.
Talanta ; 188: 27-34, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30029375

RESUMO

MicroRNAs (miRNAs) have emerged as novel biomarkers for human early-phase cancer diagnosis and disease prevention recently. Herein, we reported a novel miRNA-215 targeting biosensor, which was based on single polydiacetylene (PDA) microtube waveguide system integrated with sandwich-type hybridization design and condensing enrichment effect. The target miRNA could be captured by oligonucleotides conjugated on the surface of PDA microtube and Au nanorod (AuNR) respectively, resulting in the out-coupled fluorescence of PDA microtube quenching. In this strategy, the formation of a sandwich structure, as a result of co-hybridization of the target miRNA, enabled simplified preparation process, enhanced reaction efficiency, and increased recyclability and stability of the platform. Based on condensing enrichment effect, the co-hybridization reaction could be enriched on the surface of microtube and the proposed platform could easily achieve highly sensitive detection of miRNA-215 in one step. Remarkably, this platform could be directly applied to discriminate the miRNA-215 expression levels in clinical gastric cancerous, paracancerous and normal tissues samples. This assay offers a simple and convenient method for miRNA quantification in clinical samples, even with the potential for invasive, portable equipment for early clinical diagnosis of diseases.


Assuntos
Técnicas Biossensoriais/métodos , MicroRNAs/análise , Polímeros/química , Poli-Inos/química , Neoplasias Gástricas/diagnóstico , Sequência de Bases , Técnicas Biossensoriais/instrumentação , Sondas de DNA/genética , Fluorescência , Ouro/química , Humanos , Limite de Detecção , Microscopia de Fluorescência , Nanotubos/química , Hibridização de Ácido Nucleico , Oligodesoxirribonucleotídeos/genética , Polímero Poliacetilênico , Neoplasias Gástricas/genética
17.
Soft Matter ; 13(43): 7856-7861, 2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29018862

RESUMO

Supramolecular chirality is achieved in amphiphilic block copolymer films made through two-step fabrication: self-assembling first and then solution coating. The amphiphilic block copolymer is composed of poly(N-isopropyl acrylamide) (pNIPAM) as hydrophilic segments and poly(methyl methacrylate) with chiral side groups as hydrophobic segments. The films fabricated by two steps show sensible circular dichroism (CD) signals around a wavelength of 200 nm. However, CD signals cannot be detected from films made by directly coating the solution of copolymers on the quartz surface. The CD signal at about 200 nm is from supramolecular arrangement of benzene units connected to the chiral group in the hydrophobic segment. This result is thought to be originated from the aggregation of the copolymer during the first step of the film forming process, and the corresponding investigation into factors affecting this process has been performed in this work. It is also found that the films fabricated by two steps can adsorb chiral small molecules enantioselectively, while the films obtained by coating the solution of copolymers directly have no such enatioselective adsorption ability.

18.
Chemistry ; 23(33): 8032-8038, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28402043

RESUMO

Circularly polarized light (CPL) is considered to be a true chiral entity and has been suggested as an explanation for the introduction of initial chiral biases into key biomolecular building blocks. CPL used recently asymmetric photochemical reactions is of wavelengths mainly in the UV and visible regions, whereas natural CPL observed in star-forming regions of the Orion constellation falls in the IR region. Whether CPL in the IR or near-IR region could be utilized to trigger asymmetric photochemical reactions remains to be determined. Herein, it is demonstrated that enantioselective photopolymerization can be realized by using λ=980 nm CPL as the only chiral source. By incorporating NaYF4 nanophosphors as the antenna species, the enantioselective photopolymerization of achiral benzaldehyde-substituted diacetylene monomer can be realized based on an upconversion mechanism upon exposure to λ=980 nm CPL. The screw direction of the helical PDA chains can be completely controlled by the handedness of incident λ=980 nm CPL.

19.
Sensors (Basel) ; 17(3)2017 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-28273844

RESUMO

Gratings inscribed in polymer optical fibre (POF) have attracted remarkable interest for many potential applications due to their distinctive properties. This paper overviews the current state of fabrication of POF gratings since their first demonstration in 1999. In particular we summarize and discuss POF materials, POF photosensitivity, techniques and issues of fabricating POF gratings, as well as various types of POF gratings.

20.
Acta Radiol ; 58(11): 1342-1348, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28132530

RESUMO

Background Lymphangioleiomyomatosis (LAM) is a rare disease involving the bronchi, lymphatic vessels, and veins. However, there are few reports about lymphatic vessel abnormalities associated with LAM. Purpose To evaluate computed tomography (CT) lymphangiography findings in cases of LAM, especially lymphatic vessel abnormalities. Material and Methods Twenty-seven patients with LAM underwent direct lymphangiography (DLG), followed by a post-procedural thoracoabdominal CT examination. Results All 27 patients were diagnosed with LAM, including 25 (93%) with chylothorax, eight (30%) with chyloperitoneum, seven (26%) with chylous fluid in the chest and abdomen, and one (4%) with lower-limb lymphedema. The CT lymphangiography showed that 27/27 (100%) patients presented iliac or retroperitoneal lymphatic vessel dilation; 20/27 (74%) presented thoracic duct outlet obstruction; 9/27 (33%) presented pleural lymph leakage; and 13/27 (48%) presented an abnormal distribution of contrast agent in the contralateral lumbar trunk, 3/27 (11%) in the pulmonary field, 1/27 (4%) in the abdominal cavity, and 4/27 (15%) in the pelvic cavity. Five of the 27 patients (19%) had retroperitoneal lymphangioleiomyomas, with contrast agent accumulation in three cases during CT lymphangiography. Two of the 27 (7%) patients had enlarged lymph nodes in the retroperitoneum. All 27 patients (100%) diagnosed with LAM displayed various lung cysts on thoracic high-resolution CT scans. Conclusion CT lymphangiography findings can be used to diagnose most LAM cases accurately. Moreover, these findings also display the various lymphatic vessel abnormalities associated with LAM.


Assuntos
Linfangioleiomiomatose/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Feminino , Humanos , Vasos Linfáticos/diagnóstico por imagem , Linfografia/métodos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
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