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1.
Ecotoxicol Environ Saf ; 191: 110236, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32001424

RESUMO

Copper (Cu), a transition metal, is an essential trace element in human and animal nutrition at low concentration, but Cu has toxic effects on tissues and organs at high concentration. Endoplasmic reticulum (ER) is a toxicological target in Cu poison. Thus far, no studies have focused on the relationship among copper, endoplasmic reticulum (ER) stress and apoptosis in animal and human livers. In the present study, mice treated with copper sulfate (CuSO4) were used to assess the impacts of copper on ER stress and hepatic apoptosis. A total of 240 mice were orally administered with 0 (control), 10, 20 and 40 mg/kg of CuSO4 for 42 days. The results indicated that CuSO4 at 10 mg/kg markedly induced hepatocyte apoptosis and ER stress. In addition, ER stress was characterized by the increased mRNA and protein levels of glucose-regulated protein 78 (GRP78) and 94 (GRP94). Furthermore, ER stress-triggered 3 apoptotic pathways were also activated by the increased intracellular calcium and up-regulated expression levels of genes involved in growth arrest- and DNA damage-inducible gene 153 (Gadd153/CHOP), c-Jun N-terminal kinase (JNK) and cysteine aspartate-specific protease 12 (caspase-12) signaling pathways in CuSO4-treated mice. In conclusion, CuSO4-induced ER stress can promote hepatic apoptosis in mice by activating CHOP, JNK and caspase-12 signaling pathways.

2.
ACS Appl Mater Interfaces ; 12(1): 753-762, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31808333

RESUMO

Large energy loss is one of the key factors that limit the power conversion efficiency (PCE) of organic solar cells (OSCs). In this work, we report reduced energy losses of OSCs via introducing thiazole π-spacers with different orientations to replace the thiophene π-spacers of the prototype polymer PBDB-T. The newly formed thiazole-containing isomeric polymers, PBDBTz-2 and PBDBTz-5, exhibited blue-shifted absorption and deeper lying energy levels compared to PBDB-T. When blended with IT-4F, the two polymers realized PCEs of 10.4% for PBDBTz-2 and 9.6% for PBDBTz-5, respectively, which were higher than that of PBDB-T (PCE = 9.3%). More critically, considerable open-circuit voltage (Voc) enhancements were achieved by PBDBTz-2 and PBDBTz-5, which were 0.14 and 0.21 V higher than that of PBDB-T. A detailed analysis showed that the reduced energy loss resulted from the lower radiative recombination below the band gap and nonradiative recombination loss. This study demonstrated that the introduction of thiazole π-spacers with different orientations is effective to reduce the energy losses of OSCs, which provided valuable inspirations for the development of new conjugated polymers to the efficiency breakthrough of OSCs in future.

3.
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.

4.
Int J Mol Sci ; 20(19)2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31546657

RESUMO

Nickel (Ni) is known to be a major carcinogenic heavy metal. Occupational and environmental exposure to Ni has been implicated in human lung and nasal cancers. Currently, the molecular mechanisms of Ni carcinogenicity remain unclear, but studies have shown that Ni-caused DNA damage is an important carcinogenic mechanism. Therefore, we conducted a literature search of DNA damage associated with Ni exposure and summarized known Ni-caused DNA damage effects. In vitro and vivo studies demonstrated that Ni can induce DNA damage through direct DNA binding and reactive oxygen species (ROS) stimulation. Ni can also repress the DNA damage repair systems, including direct reversal, nucleotide repair (NER), base excision repair (BER), mismatch repair (MMR), homologous-recombination repair (HR), and nonhomologous end-joining (NHEJ) repair pathways. The repression of DNA repair is through direct enzyme inhibition and the downregulation of DNA repair molecule expression. Up to now, the exact mechanisms of DNA damage caused by Ni and Ni compounds remain unclear. Revealing the mechanisms of DNA damage from Ni exposure may contribute to the development of preventive strategies in Ni carcinogenicity.

5.
Foods ; 8(9)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547349

RESUMO

The current work aimed to clarify the effects of four structured lipids, including monoglycerides with docosahexaenoic acid (2D-MAG), diacylglycerols with caprylic acid (1,3C-DAG), triglyceride with caprylic acid at sn-1,3 and DHA at sn-2 position (1,3C-2D-TAG) and caprylic triglyceride on the oxidative stability of stripped soybean oil (SSO). The results revealed that compared to the blank group of SSO, the oxidation induction period of the sample with 2 wt% 2D-MAG and that with 1,3C-DAG were delayed by 2-3 days under accelerated oxidation conditions (50 °C), indicating that 2D-MAG and 1,3C-DAG prolonged the oxidation induction period of SSO. However, the inhibitory effect of α-tocopherol on SSO oxidation was reduced by 2D-MAG after addition of 2D-MAG to SSO containing α-tocopherol. 2D-MAG exhibited different antioxidative/pro-oxidative effects in the added/non-added antioxidants system. Compared to caprylic triglyceride, DHA at the sn-2 acyl site induced oxidation of structured lipids, thus further promoting the oxidation of SSO. The antioxidant was able to inhibit not only the oxidation of DHA in the SSO, but also the transesterification of sn-2 DHA to sn-1/sn-3 DHA in the structured lipid.

6.
Med Educ Online ; 24(1): 1666538, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31526248

RESUMO

With the increasing use of technology in education, online learning has become a common teaching method. How effective online learning is for undergraduate medical education remains unknown. This article's aim is to evaluate whether online learning when compared to offline learning can improve learning outcomes of undergraduate medical students. Five databases and four key journals of medical education were searched using 10 terms and their Boolean combinations during 2000-2017. The extracted articles on undergraduates' knowledge and skill outcomes were synthesized using a random effects model for the meta-analysis.16 out of 3,700 published articles were identified. The meta-analyses affirmed a statistically significant difference between online and offline learning for knowledge and skill outcomes based on post-test scores (SMD = 0.81; 95% CI: 0.43, 1.20; p < 0.0001; n = 15). The only comparison result based on retention test scores was also statistically significant (SMD = 4.64; 95% CI: 3.19, 6.09; p < 0.00001). The meta-analyses discovered no significant difference when using pre- and post-test score gains (SMD = 3.03; 95% CI: -0.13, 4.13; p = 0.07; n = 3). There is no evidence that offline learning works better. And compared to offline learning, online learning has advantages to enhance undergraduates' knowledge and skills, therefore, can be considered as a potential method in undergraduate medical teaching.


Assuntos
Educação a Distância , Educação de Graduação em Medicina/métodos , Ensino/normas , Humanos , Internet , Estudantes de Medicina
7.
BMC Med Educ ; 19(1): 301, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31383031

RESUMO

BACKGROUND: Research examining the effects of academic interest on students learning achievement across various disciplines, especially a comparison of the effects of academic interest between medical sciences and other disciplines, is still scarce. This study addressed this gap by answering 'does academic interest play a more important role in medical sciences than in other disciplines?'. METHODS: A retrospective cross-sectional study, based on a large project of the National Undergraduate Student Development Survey (NUSDS) conducted by the Ministry of Education of China and Peking University in 2014, was designed to explore the role of academic interest in medical sciences and other disciplines. The participants were resampled to better represent the national distribution of undergraduate students in terms of their demographic characteristics. Specifically, survey data from 54,398 undergraduate students from 87 Chinese universities and colleges were used to address our research questions. We then used the propensity score matching (PSM) model to estimate the effect of academic interest on academic achievement and to compare the effects across different disciplines. RESULTS: Academic interest had a significant positive impact on academic performance, with an effect size of 2.545 (p = 0.000). Specifically, the effect sizes for the disciplines of medical sciences, humanities, social sciences, natural sciences and engineering were 2.310 (p = 0.000), 2.231 (p = 0.000), 2.016 (p = 0.000), 3.840 (p = 0.000) and 2.698 (p = 0.000), respectively. The results show that no particular academic interest in medical sciences is needed to achieve academic success when compared with natural sciences and engineering programmes, but success in medical sciences requires more academic interest than success in humanities or social sciences. CONCLUSIONS: This study clarifies the effect of academic interest on undergraduates' academic achievement while controlling for their demographic characteristics and family factors. The results provide insights into the role of academic interest in academic performance across various disciplines and can inform the college admissions practices of both institutions and high school students in China.


Assuntos
Desempenho Acadêmico , Educação de Graduação em Medicina , Motivação , China , Estudos Transversais , Feminino , Humanos , Masculino
8.
J Anim Physiol Anim Nutr (Berl) ; 103(5): 1408-1417, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31131937

RESUMO

OBJECTIVE: Silkie chicken (Gallus gallus domesticus brisson) is also named Chinese Taihe chicken, characterized by blue comb, green earlobes, black skin, meat and bones. This study aimed to evaluate the effects of spirulina feeding on the nutritive value and flavour of silkie hens eggs. METHODS: A total of 280 Silkie hens of 42 weeks old were fed 4 different diets, including basal diet and basal diet containing 0.1%, 0.3% and 0.5% spirulina. Each diet group was divided into 70 Silkie hens experimentally. The production performance of silkie hens, the nutritional compositions [e.g., amino acids (AAs) and fatty acids] and flavour substances of silkie hens eggs were compared with control. RESULTS: A 0.3% and 0.5% spirulina feeding significantly increased the average egg production rate and average egg weight, while only 0.3% spirulina feeding decreased both the average daily feed intake and feed conversion ratio of silkie hens compared with the controls (p < 0.05). The contents of crude protein, fat, cholesterol and Ca in silkie hens eggs were significantly increased by 0.3% spirulina feeding (p < 0.05). Only fat and cholesterol were significantly increased by 0.5% spirulina but had no significant difference compared with 0.3% spirulina. The flavour, amino acids/total AAs, and saturated fatty acids/unsaturated fatty acids in silkie hens eggs were significantly increased by 0.3% spirulina feeding than other groups (p < 0.05). A total of 46 volatile substances were identified in silkie hens eggs, and the substances of total acids, alkanes and aldehydes were significantly increased by 0.3% spirulina feeding. CONCLUSION: Spirulina feeding at a proportion of 0.3% improved the production performance of silkie hens, and nutritive value and flavour of silkie hens eggs.

9.
Food Sci Nutr ; 7(4): 1261-1273, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31024699

RESUMO

Purpose: The volatile compounds that contribute to the flavor of pork are unknown. Therefore, the present study aimed to determine the differences in volatile compounds from pork meats of four different pig breeds using headspace solid-phase micro-extraction (HS-SPME)/gas chromatography-mass spectrometry (GC-MS). Methods: Piglets from four breeds (8/breed) (crossbred Ziwuling Sus scrofa [SUS] and purebreds Bamei pig [BAM], American Yorkshire pig [YOK], and Hezuo pig [HZP]) were selected. Characteristics of meat were measured. HS-SPME/GC-MS were used to analyze the volatile compounds of the meats. Results: The tenderness, taste, succulence, and broth flavor of the BAM and HZP were good. One hundred and eight volatile compounds with known molecular formulas were identified in BAM, 106 in SUS, 98 in YOK, and 98 in HZP. Sixty-four common volatile compounds were found in all four breeds. The highest relative amount of volatile compounds was found in the BAM. The compounds which may contribute to the flavor of pork were 3-methyl-1-butanol, 1-nonanal, octanal, hexanal, 2-pentyl-furan, 1-penten-3-one, N-morpholinomethyl-isopropyl-sulfide, methyl butyrate, and (E,E)-2, 4-decadienal. Conclusion: The volatile compounds in pork belong to several classes, and the highest relative amount of volatile compounds was found in BAM.

10.
ACS Appl Mater Interfaces ; 11(11): 10777-10784, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30816033

RESUMO

For organic solar cells, the vertical and lateral micro-/nanometer-scale structure in the active layer largely determines the device performance. In this work, the surface and bulk domain size of the photoactive layer are successfully manipulated with a facile two-step spraying method, that is, an ultrathin active layer by high-pressure spraying is deliberately stacked on top of the thick active layer by ultrasonic spraying. Thus, the morphology is effectively optimized with the comprehensive study of optical and electrical characteristics, such as photon absorption, exciton dissociation efficiency, and bimolecular recombination. Moreover, the novel method can be used not only in the fullerene system but also in the nonfullerene system, demonstrating the remarkable universality through this synergy method. This work provides an easy and reliable strategy to improve photovoltaic device performance in the industrial large-area spray-coating process.

11.
ACS Appl Mater Interfaces ; 11(1): 766-773, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30525389

RESUMO

In this article, we report 13%-efficiency quaternary polymer solar cell. By introducing bis-PC71BM:PC71BM into a known nonfullerene system-poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl))benzo[1,2- b:4,5- b']dithiophene)- co-(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)benzo[1,2- c:4,5- c']dithiophene-4,8-dione):3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone-methyl))-5,5,11,11-tetrakis(4- n-hexylphenyl)-dithieno[2,3 d:2',3' d']- s-indaceno[1,2 b:5,6 b']dithiophene (PBDB-T:IT-M), the quaternary solar cell significantly outperforms the nonfullerene binary and the ternary (PBDB-T:IT-M:fullerene) devices with a significant increase in the short-circuit current-density (18.2 vs 16.5 and 16.8-17.5 mA/cm2) and the fill factor (0.73 vs 0.67 and 0.707-0.726), and hence, large power conversion efficiency (13% for quaternary vs 11% for the binary and 12% for the ternary). Grazing incidence wide-angle X-ray scattering data indicate that both the polymer and IT-M phase crystallinity becomes greater upon introduction of PC71BM as the forth additive into the host ternary PBDB-T:IT-M:bis-PC71BM, which results in an increase in both the electron and hole mobilities, contributing to the Jsc enhancement. Our results indicate that the use of the forth fullerene component provides more choices and more mechanisms than the ternary systems for tuning the photon-to-electron conversion; therefore, sheds light on the realization of high-efficiency polymer solar cells by designing the multiacceptor components with aligned energy levels, complementary absorption spectra, and improved film morphologies.

12.
J Cell Physiol ; 234(4): 5153-5162, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30362512

RESUMO

Overexpression of long noncoding RNA (lncRNA) H19 has been observed in various cancers, which indicates that H19 exert important roles in the progression of carcinogenesis. MiR-326 has been reported to play tumor suppressive roles in multiple tumors. Recently, the competing endogenous RNA (ceRNA) hypothesis has implied that lncRNAs might function as molecular sponges for microRNAs in various cancers. However, the roles of H19/miR-326 in human hepatocellular carcinoma (HCC) still remain unclear. The aim of our study was to determine H19/miR-326 expression in HCC cells and investigate their roles in HCC development. We found that H19 was significantly elevated and miR-326 was decreased in HCC cells including Hep3B, HepG2, MHCC-97L, SK-hep1, Hun7, SMCC-7721 compared with LO2 cells, respectively. In the subsequent experiments, we observed that inhibition of H19 can repress HCC cell growth, migration, and invasion in vitro. H19 downregulation can increase miR-326 expression in HCC cells. Meanwhile, miR-326 mimics can also inhibit HCC progression, whereas miR-326 inhibitors exhibited a reverse phenomenon by modulating H19 expression. In addition, a negative association between H19 and miR-326 was predicted and confirmed. Furthermore, the transcription factor TWIST1 has been recognized as a significant regulator in tumor progression. Here, by performing bioinformatics analysis, TWIST1 was identified as a downstream target of miR-326. The findings of our study implied that lncRNA H19 can serve as a ceRNA to sponge miR-326 and modulate TWIST1 levels in HCC pathogenesis. Taken these together, these findings indicated that H19/miR-326/TWIST1 axis was involved in HCC development and can indicate a novel HCC target.

13.
PLoS One ; 13(12): e0208637, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30521600

RESUMO

BACKGROUND: In this study, we assessed the association of SBRT (stereotactic body radiotherapy) dose and volume with radiation pneumonitis (RP) risk in lung tumor. METHODS: Relevant articles were identified up to April 2018, using following databases; Medline, EMBASE, Cochrane Library, and China National Knowledge Infrastructure (CNKI). The pooled OR (odds ratio) with 95% CI (confidence interval) data [mean ± SD (standard deviation)] obtained from different studies was analyzed by statistical analysis using a fixed-effects model or a random-effects model when appropriate. RESULTS: The analysis was based on nine observational studies, which were identified based on the study selection criteria. Between RP and non-RP patients, no difference was observed based on age, but significant differences were observed based on planning target volume (PTV), mean ipsilateral lung dose (MLD), total MLD, and V5, V10, V20 and V40 (the percentage of lung volume exceeding 5, 10, 20 and 40 Gy). In addition, PTV >145 cm3, total MLD ≥4.7 Gy, V5 ≥26.8%, V10 >12% and V20 ≥5.8 were associated with RP risk. Overall, the grade assessments of V5 and V20 revealed moderate quality evidence. CONCLUSION: The present study indicated V5 and V20 as major risk factors for RP after SBRT treatment in lung tumor. In addition, it was observed that lung DVH (Dose Volume Histogram) patterns should be assessed more carefully, while predicting RP incidence after SBRT.


Assuntos
Neoplasias Pulmonares/radioterapia , Pneumonite por Radiação/epidemiologia , Radioterapia/efeitos adversos , Humanos , Estudos Observacionais como Assunto , Fatores de Risco
14.
ACS Appl Mater Interfaces ; 10(30): 25589-25593, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29979029

RESUMO

In this study, polymer solar cells employing poly(3-hexylthiophene) (P3HT) as a donor and fullerene derivative PC61BM (phenyl-C61-butyric acid methyl ester) or nonfullerene diketopyrrolopyrrole (DPP)-based small molecule (SF-DPPEH) as an acceptor are investigated. Device based on SF-DPPEH shows a remarkably high VOC of 1.20 V, whereas analogous device based on PC61BM only delivers a VOC of 0.64 V. Employing transient photovoltage/photocurrent techniques, we measure charge carrier lifetime and density and nongeminate recombination rate in the photoactive layer and correlate material energetics and charge recombination dynamics with the change of VOC in the devices; thus, the extent to which two factors limit VOC can be quantified.

15.
ACS Appl Mater Interfaces ; 10(26): 22485-22494, 2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29893117

RESUMO

Extremely simplified one-step roll-to-roll slot-die-printed flexible indium tin oxide (ITO)-free polymer solar cells (PSCs) are demonstrated based on the ternary blends of electron-donor polymer thieno[3,4- b]thiophene/benzodithiophene, electron-acceptor fullerene [6,6]-phenyl-C71-butyric acid methyl ester, and electron-extracting polymer poly[(9,9-bis(3'-( N, N-dimethylamino)propyl)-2,7-fluorene)- alt-2,7-(9,9-dioctylfluorene)] (PFN) at room temperature (RT) in ambient air. The flexible ITO-free PSC exhibits a comparable power conversion efficiency (PCE) with the device employing complicated two-step slot-die printing (5.29% vs 5.41%), which indicates that PFN molecules can migrate from the ternary nanocomposite toward the Ag cathode via vertical self-assembly during the one-step slot-die printing process in air. To confirm the migration of PFN, the morphology and elemental analysis as well as charge transport of different active layers are investigated by the in situ transient film drying process, transmission electron microscopy, atomic force microscopy, contact angle and surface energy, X-ray photoelectron spectroscopy, scanning electron microscopy, impedance spectroscopy, transient photovoltage and transient photocurrent, and laser-beam-induced current. Moreover, the good air and mechanical stability of the flexible device with a decent PCE achieved in 1 cm2 PSCs at RT in air suggests the feasibility of energy-saving and time-saving one-step slot-die printing to large-scale roll-to-roll manufacture in the future.

16.
ACS Appl Mater Interfaces ; 10(9): 8141-8147, 2018 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-29411601

RESUMO

In this study, we demonstrate that remarkably reduced open-circuit voltage in highly efficient organic solar cells (OSCs) from a blend of phenyl-C61-butyric acid methyl ester and a recently developed conjugated small molecule (DPPEZnP-THD) upon solvent vapor annealing (SVA) is due to two independent sources: increased radiative recombination and increased nonradiative recombination. Through the measurements of electroluminescence due to the emission of the charge-transfer state and photovoltaic external quantum efficiency measurement, we can quantify that the open-circuit voltage losses in a device with SVA due to the radiative recombination and nonradiative recombination are 0.23 and 0.31 V, respectively, which are 0.04 and 0.07 V higher than those of the as-cast device. Despite of the reduced open-circuit voltage, the device with SVA exhibited enhanced dissociation of charge-transfer excitons, leading to an improved short-circuit current density and a remarkable power conversion efficiency (PCE) of 9.41%, one of the best for solution-processed OSCs based on small-molecule donor materials. Our study also clearly shows that removing the nonradiative recombination pathways and/or suppressing energetic disorder in the active layer would result in more long-lived charge carriers and enhanced open-circuit voltage, which are prerequisites for further improving the PCE.

17.
Eur J Oral Sci ; 125(6): 419-425, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29130547

RESUMO

Human dental pulp stem cells (DPSCs) are oral mesenchymal stem cells with potential to differentiate into various cell types. Recent studies of DPSCs have focused on microRNAs (miRNAs), a class of small noncoding RNAs that play crucial roles in regulating DPSC phenotypes. In the current study, the expression of miR-140-5p was significantly decreased during lipopolysaccharide (LPS)-mediated differentiation of DPSCs in vitro. Overexpression of miR-140-5p enhanced proliferation of DPSCs and inhibited DPSC differentiation, whereas suppression of miR-140-5p produced the opposite effect. Moreover, the expression of toll-like receptor 4 (TLR-4), a critical regulator of DPSCs, was negatively correlated with the levels of miR-140-5p. A luciferase reporter analysis confirmed that miR-140-5p could regulate TLR-4 by directly binding to the 3'-untranslated region (3'-UTR) of the TLR4 mRNA. Additionally, we suppressed TLR-4 expression by treating cells with a TLR-4 inhibitor, CLI-095, and demonstrated that the effect of the miR-140-5p inhibitor on DPSC proliferation and differentiation could be partially reversed by blocking TLR-4. Taken together, our data suggest that miR-140-5p is a novel miRNA that regulates DPSC proliferation and differentiation.


Assuntos
Diferenciação Celular/genética , Proliferação de Células/genética , Polpa Dentária/citologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Odontoblastos/metabolismo , Transdução de Sinais/genética , Receptor 4 Toll-Like/genética , Apoptose , Western Blotting , Ciclo Celular , Sobrevivência Celular , Células Cultivadas , Humanos , Técnicas In Vitro , Lipopolissacarídeos , Fenótipo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
ACS Appl Mater Interfaces ; 9(23): 19998-20009, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28535032

RESUMO

A pair of linear tetrafluorinated small molecular donors, named as ThIDTTh4F and ThIDTSe4F, which are with tetrathienyl-substituted IDT as electron-rich central core, electron-deficient difluorobenzothiadiazole as acceptor units, and donor end-capping groups, but having differences in the π-bridge (thiophene and selenophene), were successfully synthesized and evaluated as donor materials in organic solar cells. Such π-bridge and core units in these small molecules play a decisive role in the formation of the nanoscale separation of the blend films, which were systematically investigated through absorption spectra, grazing incidence X-ray diffraction pattern, transmission electron microscopy images, resonant soft X-ray scattering profiles, and charge mobility measurement. The ThIDTSe4F (with selenophene π-bridge)-based device exhibited superior performance than devices based on ThIDTh4F (with thiophene π-bridge) after post annealing treatment owing to optimized film morphology and improved charge transport. Power conversion efficiency of 7.31% and fill factor of ∼0.70 were obtained by using a blend of ThIDTSe4F and PC71BM with thermal annealing and solvent vapor annealing treatments, which is the highest PCE from aromatic side-chain substituted IDT-based small molecular solar cells. The scope of this study is to reveal the structure-property relationship of the aromatic side-chain substituted IDT-based donor materials as a function of π-bridge and the post annealing conditions.

19.
Nanomaterials (Basel) ; 7(5)2017 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-28467347

RESUMO

We propose Sb-doped TiO2 as electron acceptor material for depleted CdTe nanocrystal (NC) hetero-junction solar cells. Novel devices with the architecture of FTO/ZnO/Sb:TiO2/CdTe/Au based on CdTe NC and TiO2 precursor are fabricated by rational ambient solution process. By introducing TiO2 with dopant concentration, we are able to tailor the optoelectronic properties of NC solar cells. Our novel devices demonstrate a very high open circuit voltage of 0.74 V, which is the highest Voc reported for any CdTe NC based solar cells. The power conversion efficiency (PCE) of solar cells increases with the increase of Sb-doped content from 1% to 3%, then decreases almost linearly with further increase of Sb content due to the recombination effect. The champion device shows Jsc, Voc, FF, and PCE of 14.65 mA/cm², 0.70 V, 34.44, and 3.53% respectively, which is prospective for solution processed NC solar cells with high Voc.

20.
ACS Appl Mater Interfaces ; 9(12): 10937-10945, 2017 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-28276681

RESUMO

The photovoltaic cells (PVCs) from conjugated copolymers of PDTBDT-BT and PDTBDT-FBT with 5,10-bis(4,5-didecylthien-2-yl)dithieno[2,3-d:2',3'-d']benzo[1,2-b:4,5-b']dithiophene as electron donor moieties and benzothiadiazole and/or 5,6-difluorobenzothiadiazole as electron acceptor moieties are optimized by employing alcohol-soluble PFN (poly(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)) as cathode modification interlayer. The power conversion efficiencies (PCEs) of inverted PVCs (i-PVCs) from PDTBDT-BT and PDTBDT-FBT with devices configuration as ITO/PFN/active layer/MoO3/Ag are increased from 4.97% to 8.54% and 5.92% to 8.74%, in contrast to those for the regular PVCs (r-PVCs) with devices configuration as ITO/PEDOT:PSS/active layer/Ca/Al under 100 mW/cm2 AM 1.5 illumination. The optical modeling calculations and X-ray photoelectron spectroscopy (XPS) investigations reveal that the r-PVCs and i-PVCs from the copolymers exhibit similar light harvesting characteristics, and the enhancements of the PCEs of the i-PVCs from the copolymers are mainly contributed to the favorable vertical phase separation as the strongly polymer-enriched top surface layers and slightly PC71BM (phenyl-C71-butyric acid methyl ester)-enriched bottom surface layers are correspondingly connected to the anodes and cathodes of the i-PVCs, while they are opposite in the r-PVCs. As we known, it is the first time to experimentally verify that the i-PVCs with alcohol-soluble conjugated polymers cathode modification layers enjoy favorable vertical phase separation.

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