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1.
J Fluoresc ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884826

RESUMEN

Two novel naphthalimide derivatives PTZNI-Cz and PTZNI-TPA were successfully designed and synthesized, in which phenothiazine, triphenylamine and carbazole were used as electron donors and naphthalimide was used as the electron acceptor. Their photophysical, electrochemical, and thermal properties were investigated. These derivatives showed remarkable aggregation-induced emission (AIE) effect. Furthermore, the maximum emission peaks of PTZNI-Cz and PTZNI-TPA in the thin film state are at 610 nm and 623 nm respectively, which is typical of red fluorescent materials.

2.
J Fluoresc ; 33(6): 2503-2513, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37162634

RESUMEN

Here, two novel naphthalimide derivatives SNI-Cz and SNI-DCz with AIE were designed and synthesized. The correctness of the two structures was characterized by NMR and HRMS. Their crystal structures, photophysical properties, electrochemical properties, thermal stabilities, fluorescence lifetime and yields have been characterized. Photoluminescence experiments revealed that SNI-DCz had superior properties due to the D-π-A-π-D structure and sliding away stacking of molecules. SNI-DCz exhibited weak fluorescence in pure DMF, with a significant AIE effect observed in the 40% water mixture and a sharp increase in fluorescence intensity was also observed. Cyclic voltammetry and thermogravimetric analysis indicated that SNI-DCz had good electron affinity and thermal stability. The excellent properties of SNI-DCz made it a promising emitter for optoelectronics.

3.
NPJ Digit Med ; 6(1): 15, 2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36732666

RESUMEN

Deep Reinforcement Learning (DRL) has been increasingly attempted in assisting clinicians for real-time treatment of sepsis. While a value function quantifies the performance of policies in such decision-making processes, most value-based DRL algorithms cannot evaluate the target value function precisely and are not as safe as clinical experts. In this study, we propose a Weighted Dueling Double Deep Q-Network with embedded human Expertise (WD3QNE). A target Q value function with adaptive dynamic weight is designed to improve the estimate accuracy and human expertise in decision-making is leveraged. In addition, the random forest algorithm is employed for feature selection to improve model interpretability. We test our algorithm against state-of-the-art value function methods in terms of expected return, survival rate, action distribution and external validation. The results demonstrate that WD3QNE obtains the highest survival rate of 97.81% in MIMIC-III dataset. Our proposed method is capable of providing reliable treatment decisions with embedded clinician expertise.

4.
JMIR Form Res ; 7: e39965, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36607710

RESUMEN

BACKGROUND: Internet hospitals are developing rapidly in China, and their convenient and efficient medical services are being increasingly recognized by patients. Many hospitals have set up their own internet hospitals to provide web-based medical services. Tianjin Medical University General Hospital has established a multidisciplinary and comprehensive internet hospital to provide diversified medical services according to the needs of patients. A way to further improve web-based medical services is by examining how shared decision-making (SDM) can be carried out in internet hospital diagnosis and treatment services, thereby improving patients' medical experience. OBJECTIVE: The aim of this study was to analyze the feasibility of implementing doctor-patient SDM in internet hospital diagnosis and treatment services based on patients' needs in China. METHODS: In this study, the medical data of 10 representative departments in the internet hospital of Tianjin Medical University General Hospital from January 1 to January 31, 2022, were extracted as a whole; 25,266 cases were selected. After excluding 2056 cases with incomplete information, 23,210 cases were finally included in this study. A chi-square test was performed to analyze the characteristics and medical service needs of internet hospital patients in order to identify the strengths of SDM in internet hospitals. RESULTS: The internet hospital patients from 10 clinical departments were significantly different in terms of gender (χ29=3425.6; P<.001), age (χ236=27,375.8; P<.001), mode of payment (χ29=3501.1; P<.001), geographic distribution (χ29=347.2; P<.001), and duration of illness (χ236=2863.3; P<.001). Patient medical needs included drug prescriptions, examination prescriptions, medical record explanations, drug use instructions, prehospitalization preparations, further consultations with doctors (unspecified purpose), treatment plan consultations, initial diagnoses based on symptoms, and follow-up consultations after discharge. The medical needs of the patients in different clinical departments were significantly different (χ272=8465.5; P<.001). CONCLUSIONS: Our study provides a practical and theoretical basis for the feasibility of doctor-patient SDM in internet hospitals and offers some implementation strategies. We focus on the application of SDM in web-based diagnosis and treatment in internet hospitals rather than on a disease or a disease management software. The medical service needs of different patient groups can be effectively obtained from an internet hospital, which provides the practical conditions for the promotion of doctor-patient SDM. Our findings show that the internet hospital platform expands the scope of SDM and is a new way for the large-scale application of doctor-patient SDM.

5.
J Fluoresc ; 32(5): 1833-1842, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35727382

RESUMEN

Two blue donor-acceptor fluorophores with 1,4,5-triphenylimidazole as the electron-transporting unit and phenothiazine as the hole-transporting unit were synthesized by grafting 1,4,5-triphenylimidazole moieties onto 3- and 3,7-position of the phenothiazine core and characterized by spectroscopic methods. Their thermal stability, photophysical, electrochemical and electroluminescence properties were systematically investigated. These compounds exhibit good thermal stability and show blue emission in dichloromethane solution and thin solid films. The solution-processed doped devices were fabricated by using these fluorophores as the emitting dopant in 1,3-bis(N-carbazolyl)benzene host, in which the device fabricated from the fluorophore containing two 1,4,5-triphenylimidazole moieties exhibited blue emission with a luminance of 648 cd/m2 and external quantum efficiency of 1.48%.

6.
J Fluoresc ; 28(5): 1143-1150, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30097973

RESUMEN

Three anthracen- or pyrene-based coumarin derivatives have been successfully synthesized and characterized by EA, IR and 1H NMR. The photophysical properties of all derivatives were investigated by UV-Vis and photoluminescence spectroscopic analysis. Their thermal stabilities were demonstrated by TGA. These compounds exhibit strong blue mission under ultraviolet light excitation and have potential possible to explore organic electroluminescent materials. The vacuum-processed doped devices with a configuration of ITO/TAPC (20 nm)/TBADN: b1 (x wt%, 30 nm)/TPBi (50 nm)/Liq (2 nm)/Al (150 nm) was fabricated, in which the devices based on b1 exhibited the best electroluminescence performance with a maximum brightness of 8165 cd/m2 and a maximum luminous efficiencies of 6.13 cd/A and a maximum external quantum efficiency (EQE) of 2.75%.


Asunto(s)
Antracenos/química , Cumarinas/química , Cumarinas/síntesis química , Pirenos/química , Técnicas de Química Sintética , Electroquímica , Mediciones Luminiscentes , Temperatura
7.
Dalton Trans ; 45(34): 13491-502, 2016 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-27501335

RESUMEN

A new iridium(iii) complex containing a coumarin derivative as the cyclometalated ligand (L) and a carbazole-functionalized ß-diketonate (Cz-acac-allyl) as the ancillary ligand, namely, Ir(iii) bis(3-(pyridin-2-yl)coumarinato-N,C(4))(1-(9-butyl-9H-carbazol-3-yl)hept-6-ene-1,3-dionato-O,O) [Ir(L)2(Cz-acac-allyl)], was firstly synthesized as the emissive iridium(iii) complex. Then three new phosphorescent polyhedral oligomeric silsesquioxane (POSS) materials, consisting of the emissive Ir(iii) complex and carbazole moieties covalently attached to a polyhedral oligomeric silsesquioxane (POSS) core were successfully synthesized by hydrosilylation reaction in the presence of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane (Pt-dvs) as the catalyst. These phosphorescent POSS materials offer many advantages including amorphous properties, good thermal stabilities, and good solubility in common solvents, and high purity via column chromatography. The photoluminescence spectra of the POSS materials in solution and in the solid state indicate a reduction in the degrees of interactions among the Ir(iii) complex units and concentration quenching due to the bulky POSS core. Solution processed light-emitting devices based on these phosphorescent POSS materials exhibit a maximum external quantum efficiency (EQE) of 9.77%.

8.
J Fluoresc ; 26(1): 149-54, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26498459

RESUMEN

A new inorganic­organic hybrid material based on polyhedral oligomeric silsesquioxane (POSS) capped with carbazolyl substituents, octakis[3-(carbazol-9-yl)propyldimethylsiloxy]-silsesquioxane (POSS-8Cz), was successfully synthesized and characterized. The X-ray crystal structure of POSS-8Cz were described. The photophysical properties of POSS-8Cz were investigated by using UV­vis,photoluminescence spectroscopic analysis. The hybrid material exhibits blue emission in the solution and the solid film.The morphology and thermal stablity properties were measured by X-ray diffraction (XRD) and TG-DTA analysis.

9.
Thorac Cancer ; 6(3): 338-45, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26273381

RESUMEN

BACKGROUND: Hospitalization expenses for the therapy of lung cancer are not only a direct economic burden on patients, but also the focus of medical insurance departments. Therefore, the method for classifying and analyzing lung cancer hospitalization expenses so as to predict reasonable medical cost has become an issue of common interest for both hospitals and insurance institutions. METHODS: A C5.0 algorithm is adopted to analyze factors influencing hospitalization expenses of 731 lung cancer patients. A C5.0 algorithm is a data mining method used to classify calculation. RESULTS: Increasing the number of input variables leads to variation in the importance of different variables, but length of stay (LOS), major therapy, and medicine cost are the three variables of greater importance. They are important factors that affect the hospitalization cost of lung cancer patients. In all three calculations, the classification accuracy rate of training and testing partition sets reached 84% and above. The classification accuracy rate reached over 95% after addition of the cost variables. CONCLUSION: The classification rules are proven to be in accordance with actual clinical practice. The model established by the research can also be applied to other diseases in the screening and analysis of disease hospitalization costs according to selected feature variables.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 150: 316-20, 2015 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-26056982

RESUMEN

Two new anthracen- and pyrene-based coumarin derivatives, 3-(4-(anthracen-10-yl)phenyl)coumarin (4) and 3-(4-(pyrene-1-yl)phenyl)coumarin (5), were synthesized and characterized by FT-IR, (1)H NMR, element analysis and single crystal X-ray crystallography. The UV-vis absorption and photoluminescence spectra of these coumarin derivatives were investigated. The results show that compound 4 and 5 exhibit blue and blue-green emissions, respectively, under ultraviolet light excitation. Compared with the compound 4, the emission peak of compound 5 was bathochromically shifted by about 80 nm due to the more planar structure and larger π-conjugation.

11.
J Fluoresc ; 24(3): 933-43, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24659326

RESUMEN

Two mononuclear Cu(I) complexes based on 2-(2-pyridyl)benzimidazolyl derivative ligand containing electron-transporting 1,3,4-oxadiazole group (L), [Cu(L)(PPh(3))2](BF(4)) and [Cu(L)(DPEphos)](BF(4)), where L = 1-(4-(5-(4-tert-butylphenyl)-1,3,4-oxadiazol-2-yl)benzyl)-2-(pyridin-2-yl)benzimidazole and DPEphos = bis[2-(diphenylphosphino)phenyl]ether, have been successfully synthesized and characterized. The X-ray crystal structure analyses of the ligand L and the complex [Cu(L)(PPh(3))2](BF(4)) were described. The photophysical properties of the complexes were examined by using UV-vis, photoluminescence spectroscopic analysis. The doped light-emitting devices using the Cu(I) complexes as dopants were fabricated. With no electron transporting layers employed in the devices, yellow electroluminescence from Cu(I) complexes were observed. The devices based on the complex [Cu(L)(DPEphos)](BF4) possess better performance as compared with the devices fabricated by the complex [Cu(L)(PPh(3))2](BF(4)). The devices with the structure of ITO/MoO(3) (2 nm)/NPB (40 nm)/CBP:[Cu(L)(DPEphos)](BF(4)) (8 wt%, 30 nm)/BCP (30 nm)/LiF (1 nm)/Al (150 nm) exhibit a maximum efficiency of 3.04 cd/A and a maximum brightness of 4,758 cd/m(2).


Asunto(s)
Cobre/química , Electrones , Luz , Luminiscencia , Compuestos Organometálicos/química , Oxadiazoles/química , Cristalografía por Rayos X , Transporte de Electrón , Modelos Moleculares , Estructura Molecular
12.
J Fluoresc ; 23(4): 777-83, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23504219

RESUMEN

In this paper a new cyclometalated iridium(III) coumarin complex, Ir(III)bis(3-(2-benzothiazolyl)coumarinato N,C(4))(acetylacetonate) (Ir(L)2(acac)), was synthesized and characterized. X-ray crystallography demonstrated that the iridium(III) ion is hexacoordinated by two C atoms and two N atoms from 3-(2-benzothiazolyl)coumarinato ligands and two O atoms from acac ligand, displaying distorted octahedral coordination geometry. The Ir(L)2(acac) complex has good thermal stability with less than 2 % weight-reduction occurring at 300 °C, and exhibits strong reddish orange emission. The results shown that Ir(L)2(acac) is useful for fabrication organic light-emitting diodes.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 109: 179-85, 2013 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-23524386

RESUMEN

Two new mononuclear Cu(I) complexes based on 2-(2'-pyridyl)benzimidazolyl derivative ligand containing hole-transporting carbazole (L), [Cu(L)(DPEphos)](BF4) and [Cu(L)(PPh3)2](BF4), where L=(4-(9H-carbazol-9-yl)phenyl)methyl-2-(2'-pyridyl)benzimidazole; DPEphos=bis[2-(diphenylphosphino)phenyl]ether and PPh3=triphenylphosphine, have been synthesized and characterized on the basis of elemental analysis, (1)H NMR and FT-IR spectra. The structures of the ligand L and the Cu(I) complexes were characterized by single crystal X-ray diffraction. The results reveal that in the Cu(I) complexes the central Cu(I) ions assume the irregular distorted tetrahedral geometry and are tetra-coordinated by the two nitrogen atoms from L ligand and two phosphorus atoms from ancillary ligands. The photophysical properties of the complexes were examined by using UV-vis, photoluminescence spectroscopic analysis. The complexes exhibit weak MLCT absorption bands ranging from 360 to 480 nm, and display strong orange phosphorescence in the solid states at room temperature, which is completely quenched in solutions.


Asunto(s)
Bencimidazoles/química , Carbazoles/química , Complejos de Coordinación/química , Cobre/química , Bencimidazoles/síntesis química , Carbazoles/síntesis química , Complejos de Coordinación/síntesis química , Cristalografía por Rayos X , Ligandos , Luminiscencia , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Espectroscopía Infrarroja por Transformada de Fourier
14.
Artículo en Inglés | MEDLINE | ID: mdl-23501939

RESUMEN

Two different types of fluorescent materials containing benzothiazolyl moiety, 2-(benzothiazol-2-yl)phenol derivatives and 3-(benzothiazol-2-yl)coumarin derivatives, were synthesized synchronously using ethyl cyanoacetate, appropriate aromatic aldehyde and 2-aminothiophenol as the starting materials under the catalysis of benzoic acid by one-pot reaction. This method has the advantages of mild reaction conditions, easy processing and low waste. All synthesized compounds were characterized by elemental analysis, IR, (1)H NMR spectra. The structures of 2-(benzothiazol-2-yl)phenol derivatives, 2-(benzothiazol-2-yl)phenol (BTP) and 2-(benzothiazol-2-yl)naphthol (BTN), were determined by X-ray single crystal analysis. The UV-vis absorption and photoluminescence spectra of all synthesized compounds were investigated. The 2-(benzothiazol-2-yl)phenol derivatives exhibit bright green emissions and 3-(benzothiazol-2-yl)coumarin derivatives emit bright blue light in solutions.


Asunto(s)
Benzotiazoles/síntesis química , Química Orgánica/métodos , Benzotiazoles/química , Cristalografía por Rayos X , Fluorescencia , Luminiscencia , Conformación Molecular , Espectrofotometría Ultravioleta
15.
J Fluoresc ; 22(6): 1509-12, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22736191

RESUMEN

The electroluminescent (EL) properties of a new coumarin derivative, 3-(4-(anthracen-10-yl)phenyl)-benzo[5,6]coumarin (APBC), were investigated. The results show that the EL devices comprised of vacuum vapor-deposited films using the derivative as dopant exhibited blue emission that is identical to the photoluminescence of the thin film. The electroluminescence device of ITO/2-TNATA (5 nm)/NPB (40 nm)/CBP : APBC (1.0 wt%, 30 nm)/PBD (30 nm)/LiF (1 nm)/Al (100 nm) gives a maximum luminous efficiency of 2.3 cd/A at the current density of 20 mA/cm(2), and maximum luminance of 5169 cd/m(2) at 16 V. The external quantum efficiency of the device is 1.85 %.

16.
J Fluoresc ; 22(2): 631-8, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22009154

RESUMEN

Two coumarin derivatives containing electron-transporting benzoxazolyl moiety, 7-(diethylamino)-3-(benzoxazol-2-yl)coumarin (DABOC) and 3-(benzoxazol-2-yl)benzo[5,6]coumarin (BOBC), were synthesized and characterized. The photoluminescence and electroluminescence of the compounds were investigated detailedly. The compounds exhibited strong blue-green emissions in both solution and solid states, but the devices with DABOC as the emitting layer exhibited orange emission and maximum luminous efficiency of 2.8 cd/A and maximum luminance of 8,800 cd/m(2), and the devices with BOBC displayed orange-white emission and maximum luminous efficiency of 0.13 cd/A and maximum luminance of 540 cd/m(2).


Asunto(s)
Cumarinas/química , Luminiscencia , Cumarinas/síntesis química , Estructura Molecular
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 78(1): 396-400, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21123106

RESUMEN

A new fluorescent chemosensor (A18C6-Ox) in which a monoaza-18-crown-6 is linked to a diaryl-1,3,4-oxadiazole fluorophore by a methylene spacer has been synthesized to evaluate binding interaction with the rare earth ions by means of absorption and emission spectrophotometry. Absorption spectra of A18C6-Ox showed a broad band at 289nm and there was no significant change in the presence of Sc3+, La3+, Pr3+, Sm3+, Gd3+, Tb3+, Yb3+ and Lu3+ except for Ce3+ and Eu3+. From the emission spectral change of A18C6-Ox, interaction of the rare earth ions with A18C6-Ox is very strong. The formation of A18C6-Ox complexing with Sc3+, La3+, Pr3+, Sm3+, Gd3+, Tb3+, Yb3+ and Lu3+ leads to an increase in fluorescence intensity of A18C6-Ox, while Ce3+ and Eu3+ ions interact strongly causing fluorescence quenching of A18C6-Ox. In addition, the optimal complexation stoichiometry of the rare earth ions with A18C6-Ox was investigated by the fluorescent titration.


Asunto(s)
Éteres Corona/síntesis química , Metales de Tierras Raras/química , Oxadiazoles/química , Absorción , Éteres Corona/química , Iones , Oxadiazoles/síntesis química , Soluciones , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Temperatura
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 75(3): 1036-42, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20053581

RESUMEN

Two new coumarin derivatives, 7-(N,N'-diethylamino)-3-(4-hydroxyphenyl)-coumarin and 7-(N,N'-diethylamino)-3-(4-bromophenyl)-coumarin, were synthesized successfully. Their structures were verified by single crystal X-ray crystallography. The UV-vis absorption and fluorescence of the compounds were discussed. The compounds exhibit strong blue emission under ultraviolet light excitation. The molecular structures, the lowest energy transitions and the UV-vis spectra of 7-(N,N'-diethylamino)-3-(4-hydroxyphenyl)-coumarin and 7-(N,N'-diethylamino)-3-(4-bromophenyl)-coumarin have been studied with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at B3LYP/6-31G(d) level.


Asunto(s)
Cumarinas/química , Cristalografía por Rayos X , Luminiscencia , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Molecular , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
19.
Artículo en Inglés | MEDLINE | ID: mdl-20004142

RESUMEN

A new coumarin derivative, 3-(4-(anthracen-10-yl)phenyl)-benzo[5,6]coumarin, was synthesized and characterized by FT-IR, (1)H NMR, element analysis and single crystal X-ray crystallography. The dihedral angle of benzo[5,6]coumarin ring and phenyl group is 36.15 degrees, and the dihedral angle of phenyl group and anthracene skeleton is 89.37 degrees. The UV-vis absorption and photoluminescence of the compound were discussed. The result shown that the compound exhibits high fluorescence quantum yield (Phi(F)), large Stokes shift and green emission (508 nm). The molecular structure of the compound was optimized using density functional theory (DFT) at B3LYP/6-31G(d) level, and the HOMO and LUMO levels of the compound were deduced.


Asunto(s)
Cumarinas/química , Cumarinas/síntesis química , Cristalografía por Rayos X , Luminiscencia , Modelos Moleculares , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 74(3): 719-25, 2009 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-19740699

RESUMEN

Two solvent-induced trinuclear nickel(II) clusters, [{NiL(CH(3)OH)}(2)(OAc)(2)Ni].2CH(3)OH (I) and [{NiL(C(2)H(5)OH)}(2)(OAc)(2)Ni].2C(2)H(5)OH (II), have been synthesized by the reaction of a new Salen-type bisoxime chelating ligand of 5,5'-di(N,N'-diethylamino)-2,2'-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol (H(2)L) with nickel(II) acetate tetrahydrate in different solvents. Clusters I and II were characterized by elemental analyses, IR spectra, UV-vis absorption spectra, TG-DTA and X-ray diffraction methods. In clusters I (or II), there are two ligand moieties (which provide N(2)O(2) donors), two acetate ions, two coordinated methanol (or ethanol) molecules and two crystallizing methanol (or ethanol) molecules, which result in the formation of three slightly distorted octahedral geometries around Ni(II) ions. Interestingly, nickel(II) ions in the structures of clusters I and II are all six-coordinated geometry, but clusters I and II are grown up in different solvent. Right because of this, solvent effect cause to their different crystal structures.


Asunto(s)
Níquel/química , Cristalografía por Rayos X , Modelos Moleculares , Solventes/química , Espectrofotometría , Espectrofotometría Infrarroja , Análisis Espectral
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