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1.
Nanotechnology ; 34(14)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36603211

RESUMO

Solar cell technology is an effective solution for addressing climate change and the energy crisis. Therefore, many researchers have investigated various solar cell absorbers that convert Sunlight into electric energy. Among the different materials researched, heavy pnictogen chalcohalides comprising heavy pnictogen cations, such as Bi3+and Sb3+, and chalcogen-halogen anions have recently been revisited as emerging solar absorbers because of their potential for efficient, stable, and low-toxicity solar cell applications. This review explores the recent progress in the applications of heavy pnictogen chalcohalides, including oxyhalides and mixed chalcohalides, in solar cells. We categorize them into material types based on their common structural characteristics and describe their up-to-date developments in solar cell applications. Finally, we discuss their material imitations, challenges for further development, and possible strategies for overcoming them.


Assuntos
Eletricidade , Luz Solar
2.
Nanomaterials (Basel) ; 11(12)2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34947555

RESUMO

Ternary chalcohalides are promising lead-free photovoltaic materials with excellent optoelectronic properties. We propose a simple one-step solution-phase precursor-engineering method for antimony selenoiodide (SbSeI) film fabrication. SbSeI films were fabricated by spin-coating the precursor solution, and heating. Various precursor solutions were synthesized by adjusting the molar ratio of two solutions based on SbCl3-selenourea and SbI3. The results suggest that both the molar ratio and the heating temperature play key roles in film phase and morphology. Nanostructured SbSeI films with a high crystallinity were obtained at a molar ratio of 1:1.5 and a temperature of 150 °C. The proposed method could be also used to fabricate (Bi,Sb)SeI.

3.
Vet Immunol Immunopathol ; 231: 110147, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33249263

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is a causative pathogen of PRRS, one of the most economically disastrous swine diseases. Non-structural protein 1 (NSP1) of PRRSV consists of NSP1α and NSP1ß which exhibit papain like cysteine protease activity. Recent evidence demonstrates that PRRSV NSP1 may be participated in modulating host immunity, but very few host proteins were discovered as targets for NSP1. In this study, we used RNA-seq to investigate the functional role of PRRSV NSP1 in porcine alveolar macrophages, 3D4/31 cells. Compared to empty vector (mock) transfectant, NSP1, NSP1α, and NSP1ß expressing 3D4/31 cells displayed a total of 60 genes, 63 genes, and 80 genes as differentially expressed genes (DEGs), respectively. Most of DEGs are involved in early inflammatory responses including interleukin (IL)-17 signaling pathway, chemokine signaling pathway, tumor necrosis factor (TNF)-α signaling pathway, and cell adhesion molecules. Interestingly, PRRSV NSP1 expression in 3D4/31 cells decreased mRNA transcripts of Fosb and Gdf15 known to be involved in host cell signaling or host cell protection during inflammation. Therefore, PRRSV NSP1 might block the signaling involved in host immune surveillance. Further study is required to define the mechanism on how PRRSV NSP1 protein represses mRNA transcripts of specific host genes.


Assuntos
Regulação Viral da Expressão Gênica , Macrófagos Alveolares/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Suínos/virologia , Proteínas não Estruturais Virais/genética , Animais , Linhagem Celular , Clonagem Molecular , Perfilação da Expressão Gênica/veterinária , Macrófagos Alveolares/imunologia , Anotação de Sequência Molecular , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , RNA Mensageiro/metabolismo , RNA Viral , RNA-Seq/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Transdução de Sinais , Proteínas não Estruturais Virais/metabolismo
4.
Nanomaterials (Basel) ; 10(11)2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33218079

RESUMO

Despite their comparable performance to commercial solar systems, lead-based perovskite (Pb-perovskite) solar cells exhibit limitations including Pb toxicity and instability for industrial applications. To address these issues, two types of Pb-free materials have been proposed as alternatives to Pb-perovskite: perovskite-based and non-perovskite-based materials. In this review, we summarize the recent progress on solar cells based on antimony/bismuth (Sb/Bi) chalcohalides, representing Sb/Bi non-perovskite semiconductors containing chalcogenides and halides. Two types of ternary and quaternary chalcohalides are described, with their classification predicated on the fabrication method. We also highlight their utility as interfacial layers for improving other solar cells. This review provides clues for improving the performances of devices and design of multifunctional solar systems.

5.
Nanomaterials (Basel) ; 9(12)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31757098

RESUMO

Pb-based hybrid perovskite solar cells, despite their advantages, face challenges in commercialization. In recent years, Bi-based chalcohalides are being considered as potential alternative candidates, however, their current device efficiency remains unsatisfactory. Herein, a two-step solution method is developed and applied to the fabrication of BiSI films. The method consists of the formation of Bi2S3 (step I) and its conversion to BiSI (step II). The Bi2S3 was fabricated by a thiol-amine solution process and the BiSI conversion was achieved by chemical reaction between the as-formed Bi2S3 and BiI3. It was found that the formation of BiSI was highly dependent on the Bi:S molar ratio of the Bi2O3-thiourea solution and the number of times of step I. The as-fabricated BiSI film had an optical band gap of 1.61 eV and exhibited nanorod morphology. In addition, the electronic structure is explored and discussed for solar cells applications.

6.
Vet Microbiol ; 226: 50-58, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30389043

RESUMO

Identifying the functional role of each porcine circovirus type 2 (PCV2) ORF associated with host cell modulation might provide better knowledge about the pathogenesis of postweaning multisystemic wasting syndrome (PMWS). PCV2 ORF5 was recently identified and the functional role of ORF5 during pathogenesis after PCV2 infection is largely unknown. In this study, we used RNA-seq to investigate the functional role of PCV2 ORF5 in PCV2-infected porcine epithelial cells. Our data demonstrates that PCV2 ORF5 could inhibit type I interferon (IFN) expression via transcriptional repression of genes involved in type I IFN production, thus enhancing replication of PCV2 in porcine epithelial cells. Therefore, PCV2 ORF5 might have an inhibitory role against host immune surveillance.


Assuntos
Circovirus/genética , Células Epiteliais/virologia , Interferon Tipo I/genética , Proteínas do Envelope Viral , Replicação Viral/genética , Animais , Circovirus/patogenicidade , DNA Viral/genética , Células Epiteliais/imunologia , Interações Hospedeiro-Patógeno/imunologia , Vigilância Imunológica , Interferon Tipo I/imunologia , Análise de Sequência de RNA , Suínos , Doenças dos Suínos/virologia , Replicação Viral/imunologia
7.
Reprod Domest Anim ; 53(6): 1594-1599, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30091481

RESUMO

The reproductive success of mammals is largely dependent on the interaction between maternal and foetal interfaces during early pregnancy. Particularly, immune cells which reside at the maternal endometrium can modulate the conception and placental vascularization. In this study, we analysed the transcription of genes involved in early pregnancy from endometrium and peripheral blood mononuclear cells (PBMCs) of pregnant pigs with different parity. Briefly, three groups of female pigs were divided based on parity (0, 2 and 5) and each group was artificially inseminated. Within 30 days of gestation, the total RNA was isolated from the endometrium and PBMCs of sacrificed experimental pigs and the expression patterns of genes involved in early pregnancy were monitored by quantitative real-time RT-PCR. Results indicated absence of correlation between increased parity and the expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1-α (HIF-1α) mRNA in endometrium among the groups of pigs analysed. Yet, the mRNA levels of Fas, Fas ligand (FasL) and tumour necrosis factor-α (TNF-α) in the endometrium of parity 5 sows were much higher than those of pregnant gilts (parity 0), and the mRNA ratios of both TNF-α:interleukin-4 (IL-4) and IFN-γ (interferon-γ):interleukin-10 (IL-10) in PBMCs of pregnant pigs were augmented with increasing parity. Furthermore, the mRNA levels of TNF-α and IFN-γ in PBMCs of pregnant pigs were inversely correlated with litter size. These combined results may demonstrate that increased parity of pregnant pigs leads to enhance Th1-prone immunity within the maternal-foetal interface during early pregnancy.


Assuntos
Endométrio/metabolismo , Leucócitos Mononucleares/metabolismo , Tamanho da Ninhada de Vivíparos/fisiologia , Paridade/fisiologia , RNA Mensageiro/metabolismo , Sus scrofa/fisiologia , Animais , Citocinas/genética , Citocinas/metabolismo , Feminino , Tamanho da Ninhada de Vivíparos/imunologia , Paridade/imunologia , Gravidez , RNA Mensageiro/genética , Sus scrofa/imunologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
J Vis Exp ; (137)2018 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-30059038

RESUMO

Sb2S3 is considered as one of the emerging light absorbers that can be applied to next-generation solar cells because of its unique optical and electrical properties. Recently, we demonstrated its potential as next-generation solar cells by achieving a high photovoltaic efficiency of > 6% in Sb2S3-sensitized solar cells using a simple thiourea (TU)-based complex solution method. Here, we describe the key experimental procedures for the deposition of Sb2S3 on a mesoporous TiO2 (mp-TiO2) layer using a SbCl3-TU complex solution in the fabrication of solar cells. First, the SbCl3-TU solution is synthesized by dissolving SbCl3 and TU in N,N-dimethylformamide at different molar ratios of SbCl3:TU. Then, the solution is deposited on as-prepared substrates consisting of mp-TiO2/TiO2-blocking layer/F-doped SnO2 glass by spin coating. Finally, to form crystalline Sb2S3, the samples are annealed in an N2-filled glove box at 300 °C. The effects of the experimental parameters on the photovoltaic device performance are also discussed.


Assuntos
Antimônio/química , Energia Solar/estatística & dados numéricos , Tioureia/química
9.
Int J Clin Pharm ; 40(3): 721-729, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29605947

RESUMO

Background Although warfarin is highly effective, management of patients prescribed warfarin is complex due to its narrow therapeutic window. Objective To evaluate the impact of a formal warfarin discharge education program (WDEP) on hospital readmission and treatment costs in patients who received warfarin therapy. Setting Robert Wood Johnson University Hospital Somerset in Somerville, New Jersey, USA. Method In this interventional cohort study, patients were assigned to either the WDEP group or the usual care group. The effects of the WDEP on readmission within 90 days after discharge were analyzed using Cox proportional hazards models. Factors influencing treatment cost were identified using generalized linear model with log-link function and gamma distribution. Main outcome measure Hospital readmission within 90 days and treatment costs associated with hospital readmission. Results Among 692 eligible patients, 203 in each group were matched using propensity scores and there were no statistically significant differences in the patient baseline characteristics between two groups. The risk of all-cause readmission within 90 days was significantly lower in the WDEP group compared to the usual care group (relative risk = 0.46, 95% CI 0.28-0.76). The treatment costs associated with hospital readmission in the WDEP group were 19% lower than those in the usual care group after adjusting for the study variables. Conclusion A formal, individualized WDEP provided by pharmacists resulted in significant reduction of readmission and treatment costs. The economic burden of treatment costs associated with warfarin can be controlled if well-organized warfarin education is provided to patients who received warfarin therapy.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Alta do Paciente , Educação de Pacientes como Assunto , Readmissão do Paciente/estatística & dados numéricos , Avaliação de Programas e Projetos de Saúde , Varfarina/uso terapêutico , Adulto , Idoso , Anticoagulantes/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Chem Commun (Camb) ; 51(41): 8640-3, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25900075

RESUMO

Sb2S3 sensitized solar cells are a promising alternative to devices employing organic dyes. The manufacture of Sb2S3 absorber layers is however slow and cumbersome. Here, we report the modified aqueous chemical bath synthesis of Sb2S3 absorber layers for sensitized solar cells. Our method is based on the hydrolysis of SbCl3 to complex antimony ions decelerating the reaction at ambient conditions, in contrast to the usual low temperature deposition protocol. This simplified deposition route allows the manufacture of sensitized mesoporous-TiO2 solar cells with power conversion efficiencies up to η = 5.1%. Photothermal deflection spectroscopy shows that the sub-bandgap trap-state density is lower in Sb2S3 films deposited with this method, compared to standard deposition protocols.

11.
Angew Chem Int Ed Engl ; 54(13): 4005-9, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25650302

RESUMO

The device performance of sensitizer-architecture solar cells based on a CuSbS2 light sensitizer is presented. The device consists of F-doped SnO2 substrate/TiO2 blocking layer/mesoporous TiO2 /CuSbS2 /hole-transporting material/Au electrode. The CuSbS2 was deposited by repeated cycles of spin coating of a Cu-Sb-thiourea complex solution and thermal decomposition, followed by annealing in Ar at 500 °C. Poly(2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']dithiophene)-alt-4,7(2,1,3-benzothiadiazole)) (PCPDTBT) was used as the hole-transporting material. The best-performing cell exhibited a 3.1 % device efficiency, with a short-circuit current density of 21.5 mA cm(-2) , an open-circuit voltage of 304 mV, and a fill factor of 46.8 %.

12.
Angew Chem Int Ed Engl ; 53(5): 1329-33, 2014 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-24339328

RESUMO

The photovoltaic performance of Sb2 Se3 -sensitized heterojunction solar cells, which were fabricated by a simple deposition of Sb2 Se3 on mesoporous TiO2 by an approach that features multiple cycles of spin coating with a single-source precursor solution and thermal decomposition, is reported. Poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']dithiophene)-alt-4,7(2,1,3-benzothioadiazole)] was used as the hole-transporting material. The most efficient cell exhibited a short-circuit current density of 22.3 mA cm(-2) , an open-circuit voltage of 304.5 mV, and a fill factor of 47.2 %, yielding a power conversion efficiency of 3.21 % under standard test conditions (irradiation of 1000 W m(-2) , air mass=1.5 G). The results of this study imply that the developed approach has a high potential as a simple and effective route for the fabrication of efficient and inexpensive solar cells.

13.
J Nanosci Nanotechnol ; 14(11): 8554-60, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25958562

RESUMO

We report the phase evolution of Pb(Zr0.52Ti0.48)O3 nanotubes (PZT-NTs), from the pyrochlore to perovskite phase, with an outer diameter of about 420 nm and a wall thickness of about 10 nm. The PZT-NTs were fabricated in pores of porous anodic alumina membrane (PAM) using a spin coating of PZT sol-gel solution and subsequent annealing at 500-700 degrees C in oxygen gas. The pyrochlore phase was found to be formed at 500 degrees C, and also found not to be transformed into the perovskite phase, even though annealing was performed at higher temperatures to 700 degrees C. Elementary distribution analysis of PZT-NTs embedded in PAM reveal that Pb diffusion from nanotubes into pore walls of PAM is one of the main reasons. By employing firstly an additional PbO coating on the pyrochlore nanotubes and then subsequent annealing at 700 degrees C, we have successfully achieved an almost pure perovskite phase in nanotubes. These results suggest that PbO acts as a Pb-compensation agent in the Pb- deficient PZT-NTs. Moreover, our method can be used in the synthesis of all metal-oxide materials, including volatile elements.

14.
J Nanosci Nanotechnol ; 11(2): 1346-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21456185

RESUMO

We investigate the nanopore changes near domain boundaries during the nanopore growth in porous anodic alumina (PAA) to understand the domain growth behavior with the anodization time. In order to observe the pore changes with the time, we analyze cleavage planes of PAA according to the nanopore length using a field emission scanning electron microscopy. The domain growth can be explained with three kinds of nanopore changes observed near domain boundaries: a change of pore diameter, a pore-branching, and a pore-movement.

15.
Nano Lett ; 8(7): 1813-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18540654

RESUMO

We report the first unambiguous ferroelectric properties of ultra-thin-walled Pb(Zr,Ti)O 3 (PZT) nanotube arrays, each with 5 nm thick walls and outer diameters of 50 nm. Ferroelectric switching behavior with well-saturated hysteresis loops is observed in these ferroelectric PZT nanotubes with P r and E c values of about 1.5 microC cm (-2) and 86 kV cm (-1), respectively, for a maximum applied electric field of 400 kV cm (-1). These PZT nanotube arrays (10 (12) nanotubes cm (-2)) might provide a competitive approach toward the development of three-dimensional capacitors for the terabyte ferroelectric random access memory.

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