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1.
Molecules ; 27(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35630716

RESUMO

Citrus essential oils (CEOs) possess physiological functions due to diverse aroma components. However, evidence for the effects of CEOs on exercise performance and exercise-induced fatigue is limited. The CEOs with discrepancies in components may exert different effects on the amelioration of exercise-induced fatigue. In this study, sweet orange (Citrus sinensis L.) essential oil (SEO), lemon (Citrus limon Osbeck) essential oil (LEO), and bergamot (Citrus bergamia Risso and Poit) essential oil (BEO) were chosen to explore the effect on amelioration of exercise-induced fatigue. Our results demonstrated that SEO and LEO increased the swimming time by 276% and 46.5%, while BEO did not. Moreover, the three CEOs exerted varying effects on mitigating exercise-induced fatigue via inhibiting oxidative stress, protecting muscle injury, and promoting glucose-dependent energy supply. Accordingly, BEO showed the best efficiency. Moreover, the GC-MS and Pearson correlation analysis of BEO showed that the contents of the major components, such as (±)-limonene (32.9%), linalyl butyrate (17.8%), and linalool (7.7%), were significantly positively correlated with relieving exercise-induced fatigue.


Assuntos
Citrus , Óleos Voláteis , Fadiga/tratamento farmacológico , Limoneno/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia
2.
Langmuir ; 37(14): 4347-4354, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33797928

RESUMO

In this article combining density functional theory (DFT) calculations and corresponding experimental measurements, the adsorption behaviors and working mechanism of the alcohol-soluble ionic organic interlayer on different electrode substrates were studied. The results suggest that, when the ionic organic bipyridine salt interlayer (FPyBr) is adsorbed on the Ag surface, Br- will break away from molecule chains and form new chemical bonds with the Ag substrate, as confirmed by both the X-ray photoelectron spectroscopy (XPS) study and DFT study for the first time. Charges are further found to transfer to the Ag substrate from the new interlayer molecular structure without Br-, resulting in adsorption dipoles directed from Ag to the interlayer. Moreover, the direction of the intrinsic dipole of the molecule itself on the Ag substrate is also verified, which is the same as that of the adsorption dipole. Subsequently, the superposition of the two dipoles results in a large reduction of the Ag substrate work function. In addition, the dipole formation mechanism of the interlayer on the ITO surface was also studied. The change in the work function of the ITO substrate by this interlayer is found to be smaller than that of Ag as confirmed by both a DFT study and scanning Kelvin probe microscopy (SKPM) results, which is mainly due to the reversed direction of the molecular intrinsic dipole with respect to the interfacial dipole. The worst device performance of organic solar cells based on the ITO-FPyBr substrate is considered to be one of the consequences of the feature. The findings here are of great importance for the study of the mechanism of the ionic organic interlayer in organic electronic devices, providing insightful understandings on how to further improve the material and device performance.

3.
RSC Adv ; 13(41): 29035-29042, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37799307

RESUMO

The design and synthesis of polymer donors with a low-lying highest occupied molecular orbital (HOMO) level are crucial for increasing open-circuit voltages (VOC) and achieving high-performance non-fullerene polymer solar cells. Here, we developed two copolymers using non-fluorinated or fluorinated thienyl-conjugated benzodithiophenes as electron donor units, and difluoro-quinoxaline with a naphthalimide substituent (DNB) as the electron acceptor unit. These copolymers, namely PDNB and PDNB-2F, exhibited deep HOMO levels owing to the strong electron-withdrawing ability of the naphthalimide substituent. Density-functional theory calculations demonstrated that the skeletons of the two copolymers featured good coplanarity. Owing to the fluorination, PDNB-2F displayed an increased absorption coefficient and deeper HOMO level than PDNB. Moreover, the blended film based on PDNB-2F:Y6 demonstrated enhanced carrier mobility, decreased bimolecular recombination as well as favorable phase-separation regions. Consequently, the PDNB-2F:Y6-based device yielded a superior power conversion efficiency (PCE) of 12.18%, whereas the device based on PDNB:Y6 showed a comparatively lower PCE of 8.83%. These results indicate that difluoro-quinoxaline with a naphthalimide substituent is a prospective electron-deficient building block to develop donor polymers with low-lying HOMO levels to achieve efficient non-fullerene polymer solar cells.

4.
RSC Adv ; 12(28): 17898-17904, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35765348

RESUMO

All-polymer solar cells (all-PSCs) with mechanical and thermal stability have potential for applications in flexible devices. Polymer acceptors based on naphthalene diimide (NDI) have been widely studied because of their strong electron affinity, high electron mobility, and high mechanical reliability. However, controlling the film morphology of the polymer-polymer blends of NDI-based all-PSCs is difficult. Consequently, all-PSCs based on NDI building blocks exhibit a low fill factor (FF) and a lower power-conversion efficiency (PCE) than state-of-the-art polymer solar cells. In this work, we added a small amount of dicyanodistyrylbenzene (DCB) unit to the NDI-based polymer acceptor N2200 through random copolymerization and synthesized a series of NDI-based terpolymer acceptors PNDIx, where x is the molar concentration of DCB units relative to NDI units. PNDI5 and PNDI10, corresponding to 5% and 10% molar concentrations of DCB, respectively, showed lower crystallization and good miscibility with PBDB-T, a widely used electron-donating copolymer, than the terpolymer based on DCB-free N2200. Moreover, compared to the PBDB-T:N2200 device, the PNDI5-based device exhibited a much higher PCE (8.01%), and an enhanced FF of 0.75 in all-PSCs. These results indicate that ternary random copolymerization is a convenient and effective strategy for optimizing the film morphology of NDI-based polymers, and that the resulting terpolymer acceptor is a promising n-type acceptor for constructing high-performance all-PSCs.

5.
ACS Omega ; 7(43): 38613-38621, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36340129

RESUMO

A novel conjugated molecule (PBSON) based on a main chain composed of bis(dibenzothiophene-S,S-dioxide) fused cyclopentadiene and side chains containing amino groups is presented as an efficient cathode buffer material (CBM) for organic solar cells (OSCs). PBSON showed a deep highest occupied molecular orbital (HOMO) energy level of -6.01 eV, which was beneficial for building hole-blocking layers at the cathodes of OSCs. The energy bandgap of PBSON reached 3.17 eV, implying high transmittance to visible and near-infrared light, which meant PBSON should be suitable for the applications to most inverted OSCs. The scanning Kelvin probe microscopy measurement and theoretical calculation on the PBSON/cathode interfacial interaction proved the excellent work function-regulating abilities of PBSON for various cathodes, suggesting that PBSON could promote the formation of Ohmic contacts at the cathodes and thus improve the transport and collection of electron carriers for OSCs. The characterization of electron-only devices demonstrated the good electron-transporting performance of PBSON at the cathodes. In the conventional OSCs, it was hinted that PBSON might restrain the infiltrations of evaporated cathode atoms into the active films, consequently reducing the reverse leakage currents. As a result, PBSON was able to boost the power conversion efficiencies (PCEs) by 58.2 and 56.4% for both conventional and inverted OSCs of the typical PTB7:PC71BM system, respectively, as compared to the unadorned devices. In terms of the classical PTB7-Th:PC71BM system, substantial increases in PCEs could also be found with PBSON interlayers, which were 54.7 and 59.8% for the conventional device and inverted device, respectively. Therefore, PBSON is a kind of promising CBM for realizing both conventional and inverted OSCs of high performance.

6.
RSC Adv ; 11(35): 21397-21404, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35478821

RESUMO

A wide-bandgap polymer donor with improved efficiency plays an important role in improving the photovoltaic performance of polymer solar cells (PSCs). In this study, two novel wide-bandgap polymer donors, PBDT and PBDT-S, were designed and synthesized based on a dicyanodivinyl indacenodithiophene (IDT-CN) moiety, in which benzo[1,2-b:4,5-b']dithiophene (BDT) building blocks and IDT-CN are used as electron-sufficient and -deficient units, respectively. In our study, the PBDT and PBDT-S polymer donors exhibited similar frontier-molecular-orbital energy levels and optical properties, and both copolymers showed good miscibility with the widely used narrow-bandgap small molecular acceptor Y6. Non-fullerene polymer solar cells (NF-PSCs) based on PBDT:Y6 exhibited an impressive power conversion efficiency of 10.04% with an open circuit voltage of 0.88 V, a short-circuit current density of 22.16 mA cm-2 and a fill factor of 51.31%, where the NF-PSCs based on PBDT-S:Y6 exhibited a moderate power conversion efficiency of 6.90%. The enhanced photovoltaic performance, realized by virtue of the improved short-circuit current density, can be attributed to the slightly enhanced electron mobility, higher exciton dissociation rates, more efficient charge collection and better nanoscale phase separation of the PBDT-based device. The results of this work indicate that the IDT-CN unit is a promising building block for constructing donor polymers for high-performance organic photovoltaic cells.

7.
Transl Cancer Res ; 10(2): 581-588, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35116392

RESUMO

BACKGROUND: Ileostomy was widely used during colorectal cancer (CRC) surgery and peristomal dermatitis was one of the most common stoma-relative complications. Stoma education class may reduce the rate of peristomal dermatitis. METHODS: We enrolled patients who were diagnosed with rectal cancer and underwent surgery with ileostomy between January 2018 to December 2018 at a single tertiary hospital. The general demographic information of patients along with the participation in stoma education class and the occurrence of peristomal dermatitis were analyzed. RESULTS: A total of 491 patients were included in the study, and 162 patients (32.99%) participated in the stoma education class. Eighty-five patients (17.31%) suffered peristomal dermatitis within one month after ileostomy. The rate of peristomal dermatitis in the stoma education group was significantly lower than that in the control group (11.11% vs. 20.36%, P=0.011). Regardless of the education level, the risk of peristomal dermatitis in the education group was reduced (P<0.05). Lower peristomal dermatitis rates were found in patients who were younger than 60 years (P=0.012), whose stoma were taken care of by other people (P=0.014), or without diabetes (P=0.026). Univariate and Multivariate analysis showed that stoma education was the only factor associated with the decrease in rates of peristomal dermatitis (OR =0.458, P=0.008), while diabetes was an independent risk factor (OR =3.732, P<0.001). CONCLUSIONS: Postoperative stoma education class significantly decreased the rate of peristomal dermatitis in the early postoperative period in CRC patients with ileostomy, especially for those who were younger than 60 years, received stoma care from others or without diabetes.

8.
ACS Appl Mater Interfaces ; 13(10): 12296-12304, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33682400

RESUMO

Device performance and commercialization of organic solar cells (OSCs) are strongly influenced by the characteristics of the interface layers. Cross-linked polymer interface layers with solvent-resistant properties are very compatible with large-area solution-processing methods of OSCs and may be beneficial to the environmental stability of OSCs due to the viscoelastic and cross-linked characteristics of the cross-linked polymer. In this work, a novel cross-linkable and alcohol-soluble pyridine-incorporated polyfluorene derivative, denoted as PFOPy, is synthesized and used as a cathode interface layer (CIL) in OSCs. For PFOPy, the pendant epoxy group can be effectively cross linked through cationic polymerization under thermal treatment and the pendant pyridine group can offer good alcohol solubility. Optical absorption tests of PFOPy films before/after washing by chloroform demonstrate the excellent solvent-resistance property for the cross-linked PFOPy film. Compared with the typical ZnO CIL, the cross-linked PFOPy CIL can also substantially reduce ITO's work function and form a better interface contact with the active layer. Utilizing an inverted device structure and a typical active layer of PM6:Y6, ZnO-based OSCs display an optimal power conversion efficiency (PCE) of 15.83% while PFOPy-based OSCs exhibit superior photovoltaic performance with an optimal PCE of 16.20%. Moreover, ZnO-based and PFOPy-based OSCs separately maintain 89% and 90% of the corresponding initial PCE after 12 h of illumination, indicating similarly excellent photostability. More importantly, after 26 complete thermal cycles, ZnO-based OSCs only maintain 81% of the initial PCE while PFOPy-based OSCs retain 92% of the initial PCE and exhibit obviously better thermal cycling stability, indicating that the cross-linked PFOPy CIL should offer stronger interface robustness against thermal cycling stress due to the viscoelastic and cross-linked characteristics of PFOPy. The impressive results indicate that the cross-linked PFOPy CIL would be a very promising CIL in OSCs.

9.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(10): 890-896, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33148383

RESUMO

Objective To investigate the reducing effects of shikimic acid from the total extract of Chaenomeles speciose on the differentiation of chondrocytes into hypertrophic chondrocytes by inhibiting RBL-2H3 cell degranulation. Methods The chondrocytes were identified by toluidine blue staining and tryptase immunohistochemical staining. The chondrocytes were divided into normal chondrocytes control group, C48/80 activated RBL-2H3 cell culture supernatant treatment group, 3, 10 and 30 µg/mL SA activated RBL-2H3 cell culture supernatant treatment groups. The toxicity of SA and RBL-2H3 cell supernatant were detected by MTT assay. Western blotting was used to detect the expression of collagen type II (Col2) and collagen type X (Col10) in chondrocytes. The levels of matrix metalloproteinase 13 (MMP13), soluble nuclear factor B receptor activated protein ligand (sRANKL) and bone protective factor (OPG) were determined by ELISA, and glycosaminoglycan polysaccharide (GAG) were tested by dimethylmethylene blue (DMB) colorimetry. Results (0~30) µg/mL SA had no significant effects on the growth of chondrocytes. Compared with the C48/80 activated RBI-2H3 cell supernatant treatment group, the expression of Col2 and GAG proteins increased significantly, while the expression of Col10 and MMP13 and the ratio of sRANKL/OPG decreased significantly in the SA treatment groups in a dose-dependent manner. Conclusion SA can effectively reduce the differentiation of chondrocytes into hypertrophic chondrocytes by inhibiting RBL-2H3 cell degranulation.


Assuntos
Degranulação Celular , Diferenciação Celular , Condrócitos/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Rosaceae/química , Ácido Chiquímico/farmacologia , Animais , Linhagem Celular Tumoral , Condrócitos/citologia , Mastócitos/citologia , Ratos
10.
ACS Appl Mater Interfaces ; 11(49): 45969-45978, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31694372

RESUMO

The development of effectively universal interfacial materials for both conventional and inverted polymer solar cells (PSCs) plays a very crucial role in achieving highly photovoltaic performance and feasible device engineering. In this study, two novel alcohol-soluble conjugated polymers (PBSON-P and PBSON-FEO) with bis(benzothiophene-S,S-dioxide)-fused aromatics (FBTO) as the core unit and amino as functional groups are synthesized. They are utilized as universal cathode interfacial layers for both conventional and inverted PSCs simultaneously. Ascribing to the enlarged conjugated planarity and higher electron affinity for an FBTO unit, both PBSON-P and PBSON-FEO exhibit versatile electron-transporting abilities. They show wide band gaps that are important for light absorption in inverted PSCs, at which point PBSON-P and PBSON-FEO are more progressive than some of the reported small band gap cathode interfacial materials. Importantly, PBSON-P and PBSON-FEO display deep highest occupied molecular orbital energy levels, which can block holes at the cathode and thus increase the fill factor. As a result, both conventional and inverted PSCs using PBSON-P and PBSON-FEO as cathode interlayers realize high photovoltaic performance. Therefore, this series of novel polymers are amphibious cathode interfacial materials for high-performance conventional and inverted PSCs.

11.
BMJ Open ; 8(10): e020658, 2018 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-30287665

RESUMO

OBJECTIVE: This study aimed to investigate the practice of informed consent in China from the perspective of patients. DESIGN: A qualitative study using in-depth interviews with in-hospital patients focusing on personal experience with informed consent. SETTING: Guangdong Province, China. PARTICIPANTS: 71 in-hospital patients in rehabilitation after surgical operations were included. RESULTS: Medical information is not actively conveyed by doctors nor effectively received by patients. Without complete and understandable information, patients are unable to make an autonomous clinical decision but must sign an informed consent form following the doctor's medical arrangement. Three barriers to accessing medical information by patients were identified: (1) medical information received by patients was insufficient to support their decision-making, (2) patients lacked medical knowledge to understand the perceptions of doctors and (3) patient-doctor interactions were insufficient in clinical settings. CONCLUSIONS: Informed consent is implemented as an administrative procedure at the hospital level in China. However, it has not been embedded in doctors' clinical practices because, from the perspective of patients, doctors do not fulfil the obligation of medical information provision. As a result, the informed part of informed consent was neglected by individual doctors in China. Reforming medical education, monitoring the process of informed consent in clinical settings and redesigning medical institutional arrangements are pathways to restoring the practice of informed consent and patient-centred models in China.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Consentimento Livre e Esclarecido , Pacientes Internados/psicologia , Relações Médico-Paciente , Adulto , China , Tomada de Decisões , Ética Médica , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Adulto Jovem
12.
ACS Appl Mater Interfaces ; 9(5): 4778-4787, 2017 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-28106362

RESUMO

A novel n-type conjugated polymer containing dibenzothiophene-S,S-dioxide (FSO), bispyridinium, and fluorene scaffolds in the backbone (PFSOPyCl) was synthesized and used in the cathode interfacial layers (CILs) of conventional polymer solar cells (PSCs). The high electron affinities and large planar structures of the FSO and bispyridinium units endowed this polymer with good energy level alignments with [6,6]-phenyl-C71 butyric acid methyl ester (PC71BM) and metal cathode, and excellent electron transport and extraction properties. Polymer solar cells (PSCs) based on the poly[N-9″-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT):PC71BM system with PFSOPyCl CIL exhibited simultaneous enhancement in open-circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF), while the power conversion efficiency increased from 5.47% to 6.79%, relative to the bare Al device. Besides, PSC based on the poly[4,8-bis(2-ethylhexyloxyl)benzo[1,2-b:4,5-b']dithio-phene-2,6-diyl-alt-ethylhexyl-3-fluorothithieno [3,4-b]thiophene-2-carboxylate-4,6-diyl] (PTB7):PC71BM system achieved a PCE of 8.43% when using PFSOPyCl as CIL. Hence, PFSOPyCl is a promising candidate CIL for PSCs.

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