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When the constitutive materials of photonic crystals (PCs) are stimuli-responsive, the resultant PCs exhibit optical properties that can be tuned by the stimuli. This can be exploited for promising applications in colour displays, biological and chemical sensors, inks and paints, and many optically active components. However, the preparation of the required photonic structures is the first issue to be solved. In the past two decades, approaches such as microfabrication and self-assembly have been developed to incorporate stimuli-responsive materials into existing periodic structures for the fabrication of PCs, either as the initial building blocks or as the surrounding matrix. Generally, the materials that respond to thermal, pH, chemical, optical, electrical, or magnetic stimuli are either soft or aggregate, which is why the manufacture of three-dimensional hierarchical photonic structures with responsive properties is a great challenge. Recently, inspired by biological PCs in nature which exhibit both flexible and responsive properties, researchers have developed various methods to synthesize metals and metal oxides with hierarchical structures by using a biological PC as the template. This review will focus on the recent developments in this field. In particular, PCs with biological hierarchical structures that can be tuned by external stimuli have recently been successfully fabricated. These findings offer innovative insights into the design of responsive PCs and should be of great importance for future applications of these materials.
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OBJECTIVE: To explore the independent risk factors and predictive factors of cognitive deterioration in patients of vascular cognitive impairment no dementia with subcortical ischemic vascular disease (VCIND-SIVD). METHODS: The clinical and neuropsychological characteristics of 96 VCIND-SIVD patients were collected and their cognitive states re-assessed after one year. The distribution of continuous and categorical variables was examined with univariate analysis. And Logistic regression in multivariate modeling was employed to identify the risk and predictive factors of cognitive deterioration. RESULTS: After 1-year follow-up, 8 patients dropped out, 2 died and the remainder remained. There were 48 males and 38 females with an average age of 64.3 ± 5.4 years. Among them, 17 (19.8%) deteriorated into dementia, 24 (27.9%) upgraded to normal cognition and 45 (52.3%) maintained their cognitive status. They were divided into dementia group (cognition deteriorating into dementia) and control group (elevated/sustained cognition). After univariate analysis of general information and vascular risk factors, Logistic regression demonstrated that education level (P < 0.05, OR = 0.7) was a preventive factor of dementia while age (P < 0.05, OR = 1.2), hypertension (P < 0.05, OR = 5.6) and high homocysteine (P < 0.05, OR = 4.2) were independent risk factors of dementia. After univariate analysis of neuropsychological scores, Logistic regression demonstrated that visual reproduction-immediate recall (P < 0.05, OR = 3.4), digit span forward (P < 0.05, OR = 1.2), clock drawing test (P < 0.05, OR = 6.8) and completion time of London tower (P < 0.05, OR = 5.4) were predictive factors of dementia. CONCLUSION: VCIND-SIVD patients with low score of visual reproduction-immediate recall, digit span forward, clock drawing test and completion time of London tower should receive vigorous controls of hypertension and high homocysteine.
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Isquemia Encefálica/diagnóstico , Transtornos Cognitivos/diagnóstico , Idoso , Isquemia Encefálica/psicologia , Feminino , Humanos , Leucoaraiose/diagnóstico , Leucoaraiose/psicologia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Fatores de RiscoRESUMO
It has been reported that the length of branched alkyl side chains on fused-ring electron acceptors confers different impacts on properties versus solubility of BJH blends. However, because this impact on a non-fused acceptor backbone has rarely been studied, we examined the impact of molecular optimization from alkyl chain tuning based on non-fused thiazolothiazole small-molecule acceptors. The length of the side chain on the thiophene bridge was modified from 2-butyloctyl to 2-ethylhexyl, which corresponds to small molecules TTz3(C4C6) and TTz3(C2C4), respectively. Compared with the reported TTz3(C6C8) with long alkyl side chains, TTz3(C4C6) and TTz3(C2C4) exhibited stronger molecular aggregation, higher absorption coefficients, and greater redshifted UV absorption. Unexpectedly, after the alkyl chain was slightly shortened in this type of acceptor system, devices were successfully fabricated, but it was necessary to reduce the blending concentration at low rotation speeds due to the sharp decrease in the solubility of corresponding acceptor materials. Thus, the obtained unfavorable thickness and morphology of the active layer caused a decrease in Jsc and FF. As a consequence, TTz3(C4C6)- and TTz3(C2C4)-based devices showed an unsatisfactory power conversion efficiency of 6.02% and 2.71%, respectively, when donors were paired with the wide bandgap donor J71, which is inferior to that of TTz3(C6C8)-based devices (8.76%). These results indicate that it is challenging to determine the limit of the adjustable range of side chains to modify non-fused thiazolothiazole small-molecule acceptors for high-performance non-fullerene solar cells.
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OBJECTIVE: Fibroblast growth factor 10 (FGF 10) signaling pathway is crucial to lung development and epithelial reconstruction. The aim of this study was to investigate the relationship between gene polymorphisms in FGF 10 and susceptibility to chronic obstructive pulmonary disease (COPD) in a Han population of North China. METHODS: The subjects included 220 patients with COPD (COPD group) and 285 healthy controls (control group). The COPD patients, admitted to our hospital from June 2007 to May 2012 because of acute exacerbation, included 142 males and 78 females, aging from 43 to 93 years [mean (74 ± 10)]. The control group included 183 males and 102 females, aging from 44 to 97 years [mean (72 ± 9)]. According to results of lung function testing, patients with COPD were divided into mild (8 cases), moderate (62 cases), and severe (48 cases) and very severe groups (102 cases). The genotype frequencies of FGF 10 gene single nucleotide polymorphisms (rs10473352, rs16873956, rs2973644, rs1011814, rs10402070 and rs723166) were genotyped by RFLP PCR-restriction fragment length polymorphism method and micro-sequencing (SnaPshot) technology assay. Chi-square test was used to perform the Hardy-Weinberg equilibrium test. Unconditional logistic of regression model was used to calculate odds ratio (OR) and 95%CI. The 2 groups were compared using t-test. RESULTS: The rs2973644 locus AA, GA and GG genotype frequencies in the COPD group and the control group were 108/220, 92/220, 20/220 and 167/285, 104/285, 14/285, respectively; while the frequencies of allele A and G were 308/440, 132/440 and 438/570, 132/570, respectively. The rs10473352 locus TT, TC and CC genotype frequencies in the COPD group and the control group were 142/220, 72/220, 6/220 and 202/285, 82/285, 1/285, respectively, the differences being statistically significant (χ(2) value were 6.021-6.213, P < 0.05). The rs10473352 allele T and C frequencies were 356/440, 84/440 and 486/570, 84/570, respectively, the differences being not statistically significant (χ(2) = 3.395, P > 0.05). The rs1011814 locus TT, TC and CC frequencies in mild and moderate compared with severe and very severe COPD disease were 16/68, 39/68, 13/68 and 29/150, 67/150, 54/150, respectively; while its allele T, C frequencies were 71/136, 65/136 and 125/300, 175/300, respectively; the differences being statistically significant (χ(2) values were 6.287 and 4.200, all P < 0.05). The remaining 5 tSNP (rs10473352, rs16873956, rs2973644, rs10402070 and rs723166) genotype distribution and allele frequencies were not significantly different (OR value were 0.606-1.357, P > 0.05). CONCLUSIONS: FGF 10 gene SNP sites rs2973644 and rs10473352 polymorphisms may be associated with susceptibility to COPD in Han population of North China. The SNP in rs1011814 may be associated with severity of COPD.
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Fator 10 de Crescimento de Fibroblastos/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Estudos de Casos e Controles , China/etnologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Reação em Cadeia da Polimerase , Doença Pulmonar Obstrutiva Crônica/patologia , Índice de Gravidade de DoençaRESUMO
The ternary polymerization strategy of incorporating different donor and acceptor units forming terpolymers as photovoltaic materials has been proven advantageous in improving power conversion efficiencies (PCEs) of polymer solar cells (PSCs). Herein, a series of low band gap nonconjugated terpolymer acceptors based on two different fused-ring electron-deficient building blocks (IDIC16 and ITIC) with adjustable photoelectric properties were developed. As the third component, ITIC building blocks with a larger π-conjugation structure, shorter solubilizing side chains, and red-shifted absorption spectrum were incorporated into an IDIC16-based nonconjugated copolymer acceptor PF1-TS4, which built up the terpolymers with two conjugated building blocks linked by flexible thioalkyl chain-thiophene segments. With the increasing ITIC content, terpolymers show gradually broadened absorption spectra and slightly down-shifted lowest unoccupied molecular orbital levels. The active layer based on terpolymer PF1-TS4-60 with a 60% ITIC unit presents more balanced hole and electron mobilities, higher photoluminescence quenching efficiency, and improved morphology compared to those based on PF1-TS4. In all-polymer solar cells (all-PSCs), PF1-TS4-60, matched with a wide band gap polymer donor PM6, achieved a similar open-circuit voltage (Voc) of 0.99 V, a dramatically increased short-circuit current density (Jsc) of 15.30 mA cm-2, and fill factor (FF) of 61.4% compared to PF1-TS4 (Voc = 0.99 V, Jsc = 11.21 mA cm-2, and FF = 55.6%). As a result, the PF1-TS4-60-based all-PSCs achieved a PCE of 9.31%, which is â¼50% higher than the PF1-TS4-based ones (6.17%). The results demonstrate a promising approach to develop high-performance nonconjugated terpolymer acceptors for efficient all-PSCs by means of ternary polymerization using two different A-D-A-structured fused-ring electron-deficient building blocks.
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OBJECTIVE: To describe the clinical characteristics of 3 community outbreaks of the novel influenza A (H1N1), and to compare the treatment effects of the traditional Chinese medicine with or without Oseltamivir. METHOD: The clinical records of 234 patients in 3 community outbreaks of the novel influenza A (H1N1) infection in June (n = 56), August (n = 96) and October (n = 82) of 2009 were analyzed, and the treatment effects of the traditional Chinese medicine with or without Oseltamivir were evaluated. RESULTS: The baseline characteristics, including age, temperature, indices of blood tests, hepatic and renal functions were distributed evenly between the 2 treatment groups. The overall analysis suggested that there was no significant difference between the 2 treatment groups in the duration of clinical symptoms (P > 0.05), the duration of fever (P > 0.05), and the hospitalization days (P > 0.05). However, an analysis stratified by the temperature (≥ 39°C or < 39°C) suggested that patients treated by the traditional Chinese medicine with Oseltamivir tended to suffer a shorter duration of fever [40.5 (37.3, 42.0) vs 22.0 (10.5, 30.8) hr, P < 0.01) ] in the higher temperature group. CONCLUSIONS: The traditional Chinese medicine was equivalent to oseltamivir in treating patients with the novel influenza A (H1N1) infection with lower temperature (< 39°C). Oseltamivir was effective in shortening the duration of fever in patients with temperature higher than 39°C.
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Antivirais/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Influenza Humana/tratamento farmacológico , Oseltamivir/uso terapêutico , Fitoterapia , Adolescente , Adulto , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/virologia , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , Medicina Tradicional Chinesa , Resultado do Tratamento , Adulto JovemRESUMO
Developing simple-structured and efficient near-infrared (NIR) absorbing small-molecule acceptors (SMAs) remains of great importance for commercial applications in organic solar cells (OSCs). Herein, we construct two novel thiazolothiazole-centered NIR-absorbing SMAs by alkoxy/alkylthio side chains (TTz3/TTz4) and multiple noncovalent conformational locks of S···N, S···O, and S···S. These conformational locks make both simple-structured SMAs exhibit an extended planar configuration and a red-shifted NIR absorption in comparison with the SMA with an alkyl side chain (TTz1). As expected, both SMAs show high-efficiency photovoltaic performance in the solution-processing OSCs using J71 as a donor. A higher power conversion efficiency of 8.76% with a low energy loss (0.57 eV) is obtained in the TTz3-based OSCs. It is the first report on the simple-structured and efficient NIR-absorbing SMAs, which have great potential applied in the semitransparent OSCs.
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OBJECTIVE: To investigate the curative effect of lateral position ventilation combined with vibration sputum drainage on the patients with acute respiratory distress syndrome (ARDS). METHODS: A prospective randomized controlled trial was conducted. The patients with ARDS undergoing mechanical ventilation (MV) admitted to intensive care unit (ICU) of Linyi Central Hospital from January 2013 to June 2017 were enrolled, and they were divided into simple ventilation group and combined treatment group according to random number table. The patients in both groups received etiological treatment, protective ventilation strategy, sensitive antibiotics for anti-infection, and calefacient and humidifying treatment. The patients in the simple ventilation group received bilateral discontinuous alternative lateral position ventilation [pressure controlled ventilation (PCV), tidal volume (VT) ≤ 6 mL/kg, the inhaled oxygen concentration (FiO2) and positive end expiratory pressure (PEEP) was adjusted to maintain the airway plateau pressure (Pplat) ≤ 30 cmH2O (1 cmH2O = 0.098 kPa)], and those in the combined treatment group received lateral position ventilation combined with vibration sputum drainage, twice a day, 15 minutes each time. The parameters of respiratory function and inflammation as well as excretion of sputum before and after treatment were compared between the two groups, and the complication and prognosis were recorded. RESULTS: A total of 200 patients with ARDS were included, 4 patients were excluded because of severe pneumothorax, massive hemorrhage of the digestive tract, or elevated intracranial pressure, so 196 patients were finally enrolled in the analysis. There were 98 patients in the simple ventilation group and the combined treatment group, respectively. There were no significant differences in parameters of respiratory function and inflammation as well as excretion of sputum before treatment between the two groups. After treatment, the above parameters in both groups were improved, and the effect of combined treatment was more significant. Compared with the simple ventilation group, white blood cell count (WBC), procalcitonin (PCT), C-reactive protein (CRP) at 24 hours of treatment in the combined treatment group were significantly decreased [WBC (×109/L): 9.1±1.6 vs. 11.8±3.6, PCT (µg/L): 14.5±2.4 vs. 22.7±3.2, CRP (mg/L): 32.2±6.3 vs. 67.2±7.2, all P < 0.01], the quantity of sputum excretion was significantly increased (mL: 49.3±12.5 vs. 36.8±11.8, P < 0.01); 72 hours after treatment, the oxygenation index (PaO2/FiO2) in the combined treatment group was significantly increased [mmHg (1 mmHg = 0.133 kPa): 278±28 vs. 238±39, P < 0.01], and PEEP, FiO2, airway resistance (Raw) were significantly lowered [PEEP (cmH2O): 5±2 vs. 7±3, FiO2: 0.40±0.11 vs. 0.49±0.12, Raw (cmH2O): 12.8±0.7 vs. 16.2±0.8, all P < 0.01]. There was no significant difference in static lung compliance (Cst) or Pplat between the two groups. Compared with the simple ventilation group, the duration of MV (days: 5.5±3.0 vs. 8.6±2.1), the length of ICU stay (days: 7.5±5.4 vs. 11.3±4.6) and the extraction time of artificial airway (days: 6.6±2.8 vs. 9.4±3.3) in the combined treatment group were significantly shortened (all P < 0.01). However, there was no significant difference in the 28-day mortality rate [4.1% (4/98) vs. 3.1% (3/98)], the rate of tracheotomy [2.0% (2/98) vs. 3.1% (3/98)] or the incidence of I-II skin pressure sore [1.0% (1/98) vs. 2.0% (2/98)] between simple ventilation group and the combined treatment group (all P > 0.05). No artificial airway disappearance, pneumothorax, grade III or IV pressure sore was found in the two groups. CONCLUSIONS: Compared with lateral position ventilation alone, the treatment of combined with vibration sputum drainage is more effective for improving the respiratory function of patients with ARDS, reducing infection action, shortening the duration of MV and the length of ICU stay, and improve the recovery, promote the rehabitation of patients.
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Síndrome do Desconforto Respiratório , Drenagem , Humanos , Respiração com Pressão Positiva , Estudos Prospectivos , Respiração Artificial , Escarro , VibraçãoRESUMO
Apnea is a common complication in infants infected by respiratory syncytial virus (RSV). A recent study has shown that intranasal inoculation of RSV in conscious weanling rats strengthens the apneic responses to right atrial injection of capsaicin (CAP), leading to 66% mortality. The objectives of the present study were to determine 1) whether RSV infection changes baseline minute ventilation (Ve) and arterial blood gases in anesthetized rats; 2) what the effects of RSV infection are on the respiratory responses to CAP; and 3) whether the RSV-strengthened apneic responses are age dependent. Our experiments were conducted in anesthetized and spontaneously breathing rats divided into four groups of weanling and adult rats that received either intranasal inoculation of RSV or virus-free medium. Two days after RSV infection (0.7 ml/kg), animal blood gases, baseline Ve, and Ve responses to right atrial injection of three doses of CAP (4, 16, and 64 microg/kg) were measured and compared among the four groups. Our results showed that RSV infection increased respiratory frequency (approximately 25%, P<0.05) in weanling but not adult rats, with little effect on arterial blood gases. RSV infection amplified the apneic responses to CAP in weanling but not adult rats, characterized by increases in the initial (40%) and the longest apneic duration (650%), the number of apneic episodes (139%), and the total duration of apneas (60%). These amplifications led to 50% mortality (P<0.05). We conclude that RSV infection increases respiratory frequency and strengthens the apneic responses to CAP only in anesthetized weanling but not adult rats.
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Apneia/induzido quimicamente , Apneia/fisiopatologia , Capsaicina/administração & dosagem , Infecções por Vírus Respiratório Sincicial/complicações , Infecções por Vírus Respiratório Sincicial/fisiopatologia , Fatores Etários , Animais , Animais Recém-Nascidos , Apneia/complicações , Capsaicina/efeitos adversos , Relação Dose-Resposta a Droga , Átrios do Coração/efeitos dos fármacos , Injeções , Masculino , Ratos , Ratos Endogâmicos F344RESUMO
Objective To inhibit cisplatin-induced autophagy and improve the cisplatin sensitivity of A549 cells by knockdown the silent information regulator of transcription 1 (SIRT1). Methods Both mRNA and protein levels of SIRT1 in BEAS-2B, A549 and A549/DDP cells were detected by real-time quantitative PCR and Western blotting. After cisplatin treatment, the protein levels of SIRT1, LC3, P62 and beclin-1 in A549 cells were detected by Western blotting. A549 cells were transfected by siRNA to silence SIRT1 expression. Then, the apoptotic morphology was observed by fluorescence microscopy with Hoechst33258 staining. The apoptotic rate was analyzed by flow cytometry. The expressions of SIRT1, LC3, P62, cleaved caspase-3 and poly(ADP-ribose)polymerase (PARP) were measured by Western blotting. Results Both mRNA and protein levels of SIRT1 in A549 cells and A549/DDP cells were significantly higher than those in BEAS-2B cells, and they were higher in A549/DDP cells than in A549 cells. After cisplatin treatment, the protein levels of SIRT1, LC3 and beclin-1 in A549 cells increased, while P62 decreased. After transfected with SIRT1-siRNA, the expression of SIRT1 in A549 cells decreased. Compared with cisplatin group, the number of the apoptotic cells increased with the obvious occurrence of pyknosis and nuclear fragmentation in cisplatin plus SIRT1-siRNA group. Moreover, the expressions of P62, cleaved caspase-3 and PARP were up-regulated accompanied with LC3 decrease. Conclusion SIRT1 is highly expressed in A549 cells. The sensitivity of A549 cells to cisplatin can be improved by inhibiting the cisplatin-induced autophagy through knockdown of SIRT1.
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Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Cisplatino/farmacologia , Sirtuína 1/genética , Células A549 , Apoptose/efeitos dos fármacos , Humanos , RNA Interferente Pequeno/genética , Sirtuína 1/análise , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/fisiologiaRESUMO
To simultaneously improve both open-circuit voltage (Voc) and short-circuit current density (Jsc) for organic solar cells, a novel D(A-π-Ar)3 type of photovoltaic small molecules of TPA(FxBT-T-3Cz)3 was designed and synthesized, which contain central triphenylamine (TPA), terminal carbazole (Cz), armed fluorine-substituted benzothiadiazole (FxBT, where x = 1 or 2), and bridged thiophene (T) units. A narrowed ultraviolet-visible absorption and a decreasing highest occupied molecular orbital energy level were observed from TPA(F1BT-T-3Cz)3 to TPA(F2BT-T-3Cz)3 with increasing fluorine substitution. However, the TPA(F2BT-T-3Cz)3/PC71BM-based solar devices showed a rising Voc of 1.01 V and an enhanced Jsc of 10.84 mA cm-2 as well as a comparable power conversion efficiency of 4.81% in comparison to the TPA(F1BT-T-3Cz)3/PC71BM-based devices. Furthermore, in comparison to the parent TPA(BT-T-3Cz)3 molecule without fluorine substitution, the fluorine-substituted TPA(FxBT-T-3Cz)3 molecules exhibited significantly incremental Voc and Jsc values in their bulk heterojunction organic solar cells, owing to fluorine incorporation in the electron-deficient benzothiadiazole unit.
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Resently, we treated a 69-year-old patient with squamous cell carcinoma of lung with osteoclast-like giant cells which were similar with the giant cell tumor of bone. The clinical and pathological characteristics of this case were presented, and the literatures were reviewed. The tumor differed histologically from the pleomorphic carcinoma, which occurs most commonly in the lung and showed diverse pleomorphic manifestation with benign looking osteoclast-like multinucleated cells and bizarre giant cells. In addition, undifferentiated carcinoma with a sarcoma-like appearance containing small areas of papillary adenocarcinoma was evident in the tumor. Histological features and immunohistochemical staining could be helpful in differential diagnosis.
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Carcinoma de Células Escamosas/patologia , Tumores de Células Gigantes/patologia , Neoplasias Pulmonares/patologia , Osteoclastos/patologia , Idoso , Biomarcadores Tumorais/análise , Biópsia , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/terapia , Diferenciação Celular , Quimiorradioterapia Adjuvante , Diagnóstico Diferencial , Tumores de Células Gigantes/química , Tumores de Células Gigantes/terapia , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/química , Neoplasias Pulmonares/terapia , Masculino , Osteoclastos/química , Pneumonectomia , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
Two isomeric A-Ar-A-type small molecules of DPP2An(9,10) and DPP2An(2,6), were synthesized with two acceptor arms of diketopyrropyrroles (DPP) and a planar aryl hydrocarbon core of the different substituted anthracene (An), respectively. Their thermal stability, crystallinity, optoelectronic, and photovoltaic performances were investigated. Significantly red-shifted absorption profile and higher HOMO level were observed for the DPP2An(2,6) with 2,6-substituted anthracene relative to the DPP2An(9,10) with 9,10-substituted anthracene, as the former exhibited better planarity and a larger conjugate system. As a result, the solution-processing solar cells based on DPP2An(2,6) and PC71BM (w/w,1:1) displayed remarkably increased power conversion efficiency of 5.44% and short-circuit current density (Jsc) of 11.90 mA/cm(2) under 1% 1,8-diiodooctane additive. The PCE and Jsc values were 3.7 and 2.9 times those of the optimized DPP2An(9,10)-based cells, respectively. This work demonstrates that changing the linkage position of the anthracene core in the A-Ar-A-type SMs can strongly improve the photovoltaic properties in organic solar cells.
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Monodispersed particles of amorphous calcium carbonate (ACC) 90 to 200 nm in diameter are accessible at room temperature in ethylene glycol and water using a vortex fluidic device (VFD). The ACC material is stable for at least two weeks under ambient conditions.
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Carbonato de Cálcio/síntese química , Carbonato de Cálcio/química , Etilenoglicol/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Água/químicaRESUMO
3D magnetophotonic crystal (3D-MPC) film is an excellent platform for tailoring the magneto-optical response of magnetic materials. However, its fabrication is a great challenge due to the limitation of commonly used artificial synthesis methods. Inspired by the unique structures of biospecies, we hereby manipulate the pristine single wing scales of Morpho didius precisely and successfully fabricate Fe3O4 films with photonic structure. The synthesis strategy involves the fabrication of Fe2O3 film from a single wing scale using an improved sol-gel method followed by a subsequent reduction. The intrinsic hierarchical photonic structures as well as the anisotropic optical properties of the pristine butterfly wing scale have been retained in the obtained Fe2O3 and Fe3O4 films. When investigated under an external magnetic field, a spectral blue shift about 43 nm is observed in the designated orientation of the Fe3O4 film, which is useful for the design and creation of novel magnetic-optical modulator devices. Furthermore, these single scales can be used as building blocks to fabricate designable and more complicated assembled nano systems. This biomimetic technique combined with the variety of structures of butterfly wing scales provides an effective approach to produce magneto-photonic films with desired structure, paving a new way for theoretical research and practical applications.
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Magnetismo , Nanoestruturas/química , Cristalização , Compostos Férricos/química , Óxido Ferroso-Férrico/química , Oxirredução , EspectrofotometriaRESUMO
We herein report a new class of photonic crystals with hierarchical structures, which are of color tunability over pH. The materials were fabricated through the deposition of polymethylacrylic acid (PMAA) onto a Morpho butterfly wing template by using a surface bonding and polymerization route. The amine groups of chitosan in Morpho butterfly wings provide reaction sites for the MAA monomer, resulting in hydrogen bonding between the template and MAA. Subsequent polymerization results in PMAA layers coating homogenously on the hierarchical photonic structures of the biotemplate. The pH-induced color change was detected by reflectance spectra as well as optical observation. A distinct U transition with pH was observed, demonstrating PMAA content-dependent properties. The appearance of the unique U transition results from electrostatic interaction between the -NH3(+) of chitosan and the -COO(-) groups of PMAA formed, leading to a special blue-shifted point at the pH value of the U transition, and the ionization of the two functional groups in the alkali and acid environment separately, resulting in a red shift. This work sets up a strategy for the design and fabrication of tunable photonic crystals with hierarchical structures, which provides a route for combining functional polymers with biotemplates for wide potential use in many fields.
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Biomimética/métodos , Nanoestruturas/química , Nanotecnologia/métodos , Fótons , Animais , Borboletas/anatomia & histologia , Concentração de Íons de Hidrogênio , Fenômenos Ópticos , Polimerização , Ácidos Polimetacrílicos/química , Propriedades de Superfície , Asas de AnimaisRESUMO
We demonstrated previously that 30min of hypoxic preconditioning (HPC) applied 1day before 10min of transient global cerebral ischemia (tGCI) reduced neuronal loss in the hippocampal CA1 subregion in adult rats. The aim of the present study was to investigate the role of Na(+)/K(+)-ATPase and protein kinase Mζ (PKMζ) in the protective effect of HPC against tGCI in adult rats. We found that the activity of Na(+)/K(+)-ATPase decreased in the hippocampal CA1 subregion after 10min of tGCI. This effect was not seen after 30min of HPC in adult rats. Corresponding to the changes in Na(+)/K(+)-ATPase activity, the surface expression of Na(+)/K(+)-ATPase α1 subunit increased after HPC. Furthermore, HPC dramatically reduced the number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells in the hippocampal CA1 subregion after tGCI. However, neither PKMζ nor phosphorylation of PKMζ was changed after tGCI or HPC. The results of the present study are consistent with the hypothesis that both enhanced recovery of Na(+)/K(+)-ATPase activity due to preserved the protein levels of Na(+)/K(+)-ATPase α1 subunit and reduced DNA fragmentation after tGCI contribute to the protection afforded by HPC. However, PKMζ activation does not appear to play a role in this neuroprotection.