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1.
Animal ; 16(6): 100546, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35636330

RESUMO

Understanding the dynamic inter-relationship between grazing animals and the pasture sward is critical for sustainable grazing management. A field study was conducted to investigate the relationships between the quantity and quality characteristics of forages and diet selection of 30-kg Mongolian ewes in different seasons in Bromus inermis improved meadow steppe. Using a residual herbage mass method (1 000 kg/ha in spring, 800 kg/ha in summer and 600 kg/ha in autumn) to adjust stocking rate, three seasonal rest grazing strategies (spring rest, summer rest and autumn rest) combined with continuous grazing were studied. In each season, diet selection of sheep, quantified by diet composition and selectivity index, was estimated using a plant wax marker technique. Quantity (dry weight proportion, coverage, frequency, density and height) and quality (CP, NDF, ADF and DM digestibility) characteristics of forages consumed by sheep were determined simultaneously. Our results showed that in spring with the highest sward availability (herbage mass), diet selection of sheep could be predicted by the positive linear relationship between quality characteristics of forages and their selectivity index. In summer, the diet selection could be predicted by both positive linear relationship between quality characteristics and selectivity index, and the relationship between quantity characteristics and diet composition. While in autumn with the lowest sward availability, it could be predicted by the positive linear relationship between quantity characteristics and diet composition. During the whole grazing season, the diet composition of B. inermis (40.4%) and Leymus chinensis (35.1%) were larger than that of Potentilla bifurca (9.5%) and Carex (15.1%) and the selectivity index of P. bifurca was the highest (0.62), followed by Carex (0.17) and B. inermis (0.05), and L. chinensis (-0.29) was the lowest. The two parameters of diet selection above were positively related to their quantity and quality characteristics, respectively. These results suggested that the influence of quality characteristics on diet selection of sheep decreased gradually as a result of the decline in sward availability, while the influence of quantity characteristics increased. This study provides a comprehensive understanding of diet selection of sheep examining the trade-offs between quantity and quality characteristics of forages. The knowledge of diet selection of sheep and the corresponding prediction regressions acquired in this study could give the basis for designing appropriate grazing management strategies.


Assuntos
Ração Animal , Dieta , Ração Animal/análise , Animais , Dieta/veterinária , Feminino , Poaceae , Estações do Ano , Ovinos
2.
Braz. j. biol ; Braz. j. biol;80(4): 948-956, Oct.-Dec. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1142528

RESUMO

Abstract Mucosal epithelial cells act as the first immunologic barrier of organisms, and contact directly with pathogens. Therefore, hosts must have differential strategies to combat pathogens efficiently. Reactive oxygen species (ROS), as a kind of oxidizing agents, participates in the early stage of killing pathogens quickly. Recent reports have revealed that dual oxidase (DUOX) plays a key role in mucosal immunity. And the DUOX is a transmembrane protein which produces ROS as their primary enzymatic products. This process is an important pattern for eliminating pathogens. In this review, we highlight the DUOX immunologic functions in the respiratory and digestive tract of vertebrates.


Resumo As células epiteliais da mucosa atuam como a primeira barreira imunológica dos organismos e entram em contato direto com os patógenos. Portanto, os hospedeiros devem ter estratégias diferenciadas para combater os patógenos de forma eficiente. Trabalhos recentes revelaram que a oxidase dupla (DUOX) desempenha um papel fundamental para a imunidade da mucosa. A DUOX é uma proteína transmembrana geradora de espécies reativas de oxigênio (EROs) como seus principais produtos enzimáticos. Nesta revisão, apresentaremos as funções imunológicas da DUOX no trato respiratório e digestivo dos vertebrados.


Assuntos
Animais , Vertebrados , NADPH Oxidases , Espécies Reativas de Oxigênio , Oxidases Duais
3.
Braz J Biol ; 80(4): 948-956, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31778477

RESUMO

Mucosal epithelial cells act as the first immunologic barrier of organisms, and contact directly with pathogens. Therefore, hosts must have differential strategies to combat pathogens efficiently. Reactive oxygen species (ROS), as a kind of oxidizing agents, participates in the early stage of killing pathogens quickly. Recent reports have revealed that dual oxidase (DUOX) plays a key role in mucosal immunity. And the DUOX is a transmembrane protein which produces ROS as their primary enzymatic products. This process is an important pattern for eliminating pathogens. In this review, we highlight the DUOX immunologic functions in the respiratory and digestive tract of vertebrates.


Assuntos
NADPH Oxidases , Vertebrados , Animais , Oxidases Duais , Espécies Reativas de Oxigênio
4.
Nanoscale ; 9(42): 16396-16403, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29058001

RESUMO

The fresh water crisis has emerged as one of the most urgent bottlenecks hindering the rapid development of modern industry and society. Solar energy-driven water evaporation represents a potential green and sustainable solution to address this issue. Herein, for the first time, centimeter-scale BiInSe3-coated nickel foam (BiInSe3@NF) as an efficient solar-enabled evaporator was successfully achieved and exploited for solar energy-driven water evaporation. Benefitting from multiple scattering-induced light trapping of the rough substrate, strong light-matter interaction and intermediate band (IB)-induced efficient phonon emission of BiInSe3, the BiInSe3@NF device achieved a high evaporation rate of 0.83 kg m-2 h-1 under 1 sun irradiation, which is 2.5 times that of pure water. These figures-of-merit are superior to recently reported state-of-the-art photothermal conversion materials, such as black titania, plasmonic assembly and carbon black. In addition, superior stability over a period of 60 days was demonstrated. In summary, the current contribution depicts a facile scenario for design, production and application of an economical and efficient solar-enabled BiInSe3@NF evaporator. More importantly, the phonon engineering strategy based on alloying induced IB states can be readily applied to other analogous van der Waals materials and a series of superior vdWM alloys toward photothermal applications can be expected in the near future.

5.
Nanoscale ; 9(40): 15673-15684, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-28994431

RESUMO

Nanodiamonds (NDs) have recently become a focus of interest from the viewpoints of both science and technology. Their intriguing properties make them suitable as biologically active substrates, in biosensor applications as well as diagnostic and therapeutic biomedical imaging probes. Here, we demonstrate that NDs, as oxidation and reduction catalysts, possess intrinsic enzyme mimetic properties of oxidase, peroxidase and catalase, and these behaviors can be switched by modulating the pH value. NDs not only catalyze the reduction of oxygen (O2) and hydrogen peroxide (H2O2) at acidic pH, but also catalyze the dismutation decomposition of H2O2 to produce O2 at alkaline pH. It was proposed that the molecular mechanism of their peroxidase-like activity is electron-transfer acceleration, the source of which is likely derived from oxygen containing functional groups on their surface. Based on the color reaction, a nanodiamond-based enzyme linked immunosorbent assay (ELISA) was established for the detection of immunoglobulin G (IgG). Surprisingly, NDs display an excellent antioxidant activity due to the protective effect against H2O2-induced cellular oxidative damage. These findings make NDs a promising enzyme mimetic candidate and expand their applications in biocatalysis, bioassays and nano-biomedicine.


Assuntos
Imunoensaio , Nanodiamantes , Ensaio de Imunoadsorção Enzimática , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Imunoglobulina G/análise , Oxirredução , Estresse Oxidativo , Oxigênio/química
6.
Nanoscale ; 9(32): 11806-11813, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28786467

RESUMO

As one of the transition metal dichalcogenide materials, WSe2 in the form of a few layers (nanosheets) have received much attention due to their unique physical, optical and electrical properties. Herein, we demonstrate that WSe2 nanosheets possess intrinsic enzyme mimic activity. Under acidic conditions, they exhibit pronounced peroxidase-like property. The Michaelis-Menten kinetics indicate that the catalytic activity of WSe2 nanosheets is comparable to that of horseradish peroxidase. Based on the color reaction, a platform of WSe2 nanosheets was constructed to detect glucose concentration and it showed high sensitivity and high selectivity, which means that WSe2 nanosheets with peroxidase-like property can be used to develop a highly sensitive and selective colorimetric method for glucose detection. Moreover, due to the electron-transferring and antioxidant properties of WSe2 few layers, the peroxidase-like catalysis is proposed. These findings pave the way for further application of WSe2 nanosheets in nano-biomedicine.


Assuntos
Colorimetria , Glucose/análise , Nanoestruturas , Compostos de Selênio/química , Tungstênio/química , Catálise , Peróxido de Hidrogênio , Peroxidase
7.
Climacteric ; 20(5): 448-455, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28569074

RESUMO

OBJECTIVES: The platelet-to-lymphocyte ratio (PLR) is a predictive clinical biomarker for different cancers. However, the results of several studies investigating the association between the PLR and the prognosis of ovarian cancer have been inconclusive. Therefore, there is a need to conduct a meta-analysis to estimate the prognostic value of the PLR in ovarian cancer. METHODS: We searched the EMBASE, Medline, PubMed, and Web of Science databases to identify clinical studies that had evaluated the association between the PLR and ovarian cancer prognosis. Outcomes evaluated included overall survival (OS) and progression-free survival (PFS). We also analyzed PLR differences between malignant ovarian masses and the controls. RESULTS: Twelve relevant studies that comprised 2340 patients were selected for the meta-analysis. The results revealed that elevated PLR was significantly associated with poor OS (hazard ratio (HR) 1.63, 95% confidence interval (CI) 1.05-2.56, p < 0.01) and PFS (HR 1.61, 95% CI 1.03-2.51, p < 0.01). The PLRs in malignant cases were higher than in controls (mean difference = 63.57, 95% CI 39.47-87.66, p < 0.00001). CONCLUSION: An elevated PLR is associated with poor prognosis in patients with ovarian cancer. The PLR could be employed as a prognostic marker in patients with ovarian cancer.


Assuntos
Contagem de Linfócitos , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/diagnóstico , Contagem de Plaquetas , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , MEDLINE , Pessoa de Meia-Idade , Neoplasias Ovarianas/mortalidade , Prognóstico , Modelos de Riscos Proporcionais , Fatores de Risco , Taxa de Sobrevida
8.
Braz. j. biol ; Braz. j. biol;2017.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467350

RESUMO

Abstract Mucosal epithelial cells act as the first immunologic barrier of organisms, and contact directly with pathogens. Therefore, hosts must have differential strategies to combat pathogens efficiently. Reactive oxygen species (ROS), as a kind of oxidizing agents, participates in the early stage of killing pathogens quickly. Recent reports have revealed that dual oxidase (DUOX) plays a key role in mucosal immunity. And the DUOX is a transmembrane protein which produces ROS as their primary enzymatic products. This process is an important pattern for eliminating pathogens. In this review, we highlight the DUOX immunologic functions in the respiratory and digestive tract of vertebrates.


Resumo As células epiteliais da mucosa atuam como a primeira barreira imunológica dos organismos e entram em contato direto com os patógenos. Portanto, os hospedeiros devem ter estratégias diferenciadas para combater os patógenos de forma eficiente. Trabalhos recentes revelaram que a oxidase dupla (DUOX) desempenha um papel fundamental para a imunidade da mucosa. A DUOX é uma proteína transmembrana geradora de espécies reativas de oxigênio (EROs) como seus principais produtos enzimáticos. Nesta revisão, apresentaremos as funções imunológicas da DUOX no trato respiratório e digestivo dos vertebrados.

9.
Nanotechnology ; 27(42): 425206, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27632529

RESUMO

Among the numerous nonlinear optics effects, second harmonic generation (SHG) is always a hotspot and it is extensively used for optical frequency conversion, biomedical imaging, etc. However, SHG is forbidden in a medium with inversion symmetry under the electric-dipole approximation. Here, we demonstrated SHG from a single amorphous selenium (a-Se) nanosphere under near-infrared femtosecond pulse excitation. It was found that SH spectra are tunable with the size of a-Se nanospheres and the SHG efficiency of a single a-Se sphere with a diameter over 300 nm is estimated at 10(-8). We also established two physical mechanisms of SHG from the amorphous nanospheres. There is an electric-dipole contribution to the second-order nonlinearity in view of the inevitable structural discontinuity at the surface. The discontinuity of the normal component of the electric field strength leads to the quadrupole-type contributions arising from the large electric field gradient. The SHG process can be enhanced by resonance near the fundamental wavelength, giving rise to the detectable second harmonic (SH) spectra of a single a-Se nanosphere (d > 300 nm) or two small a-Se nanospheres (d = 200 nm) aggregated into a dimer, while the single nanosphere with smaller size (d > 300 nm) is undetectable. As an essential trace element for animals, a-Se features unique biological compatibility and has specific properties of optical nonlinearity within the optical window in biological tissue. This discovery makes a-Se nanospheres promising both in nonlinear optics and biomedicine.

10.
Genet Mol Res ; 15(2)2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27173285

RESUMO

The polypeptide N-acetylgalactosaminyltransferase-like protein 5 (GALNTL5) is a newly identified protein that is specifically expressed in testis tissue and participates in spermatogenesis. In this study, we characterized a novel bovine GALNTL5 splice variant, designated as GALNTL5-AS, by using real-time polymerase chain reaction (RT-PCR) and clone sequencing methods. The novel GALNTL5 isoform was derived from the complete transcript, GALNTL5-complete, via alternative splicing (AS). The pattern of the splice variant was exon skipping. Bovine GALNTL5 transcripts were expressed in the testis, as demonstrated by RT-PCR. The expression levels of both transcripts were higher in adult testes than in calf testes (P < 0.05). In addition, prediction analysis showed that the GALNTL5-AS transcript only encoded 122 amino acids and lost its glycosyltransferase 1 and Gal/GalNAc-T motifs, which may result in a dysfunctional protein compared with the predominant transcript GALNTL5-complete. This study improves our understanding of the bovine GALNTL5 gene function during bull sperm formation.


Assuntos
Processamento Alternativo , N-Acetilgalactosaminiltransferases/genética , Testículo/metabolismo , Motivos de Aminoácidos , Animais , Bovinos , Éxons , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , N-Acetilgalactosaminiltransferases/química , N-Acetilgalactosaminiltransferases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
J Fish Biol ; 88(6): 2188-202, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27108774

RESUMO

In this study, the full-length complementary (c)DNA of common carp Cyprinus carpio melanoma differentiation-associated gene 5 (mda5) was cloned. The complete open reading frame of C. carpio mda5 contained 2982 bp and encodes 993 amino acids. The deduced amino acids contained six functional domains: two caspase activation and recruitment domains (CARD), a conserved restriction domain of bacterial type III restriction enzyme (ResIII), a DExD/H box-containing domain (DEXDc), a helicase super family C-terminal domain (HELICc) and a C-terminal regulatory domain (RD). The mda5 gene was expressed in all tested tissues, with high levels in the gills and spleen, while lower expressed in gonad and blood. The copy numbers of mda5 were increased in the liver, spleen, head kidney and the mucosal-associated immune tissues such as the foregut, hindgut, gills and skin after stimulation with polyinosinic polycytidylic [poly(I:C)] and Aeromonas hydrophila. The myxovirus resistance gene (mx) messenger (m)RNA levels in the spleen, head kidney, foregut and gills were significantly up-regulated after poly(I:C) injection. When injected with poly(I:C), mda5 and mx transcripts were also significantly induced in vitro. These results implied that mda5 might be involved in both antiviral and antibacterial innate immune processes in C. carpio. © 2016 The Authors. Journal of Fish Biology © 2016 The Fisheries Society of the British Isles.


Assuntos
Carpas/imunologia , Proteínas de Peixes/genética , Imunidade Inata , Helicase IFIH1 Induzida por Interferon/genética , Sequência de Aminoácidos , Animais , Carpas/microbiologia , Carpas/virologia , Clonagem Molecular , Proteínas de Peixes/metabolismo , Helicase IFIH1 Induzida por Interferon/metabolismo , Poli I-C/imunologia , RNA Mensageiro/metabolismo , Análise de Sequência de DNA
12.
Nanoscale ; 8(17): 9226-33, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27087484

RESUMO

Hollow ZnO microcolumns with size induced photoluminescence and cathodoluminescence properties were prepared by a thermal chemical vapor transport and condensation method. It was found that the luminescence emission could be confined in the nano-sized hollow core and the wavelength dependent light intensity could be influenced by the geometric structure of the ZnO microcolumn, which can act as a hollow optical waveguide. Based on the antiresonant reflection in the optical waveguide, we established a theoretical model to address the field enhancement in the hollow ZnO microcolumn, which systematically clarifies the influence of the geometric structure of the microcolumn on the field enhancement. We report for the first time, the enhanced emission of the near ultraviolet light (working wavelength of 385 nm) along the axial direction of the ZnO microcolumn. The corresponding microsized light emitter has also been obtained. Experiments agree well with both theoretical predictions and computer simulations based on the finite-difference time-domain method with perfectly matched layer boundary conditions. These findings provide valuable information for the application of ZnO micro- and nanostructures in optoelectronic devices.

13.
Nanoscale ; 8(9): 5015-23, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26864279

RESUMO

The design of highly efficient, durable, and earth-abundant catalysts for the oxygen evolution reaction (OER) is crucial in order to promote energy conversion and storage processes. Here, we synthesize amorphous mixed-metal (Ni-Fe) hydroxide nanostructures with a homogeneous distribution of Ni/Fe as well as a tunable Ni/Fe ratio by a simple, facile, green and low-cost electrochemical technique, and we demonstrate that the synthesized amorphous nanomaterials possess ultrahigh activity and super long-term cycle stability in the OER process. The amorphous Ni0.71Fe0.29(OH)x nanostructure affords a current density of 10 mA cm(-2) at an overpotential of a mere 0.296 V and a small Tafel slope of 58 mV dec(-1), while no deactivation is detected in the CV testing even up to 30 000 cycles, which suggests the promising application of these amorphous nanomaterials in electrochemical oxidation. Meanwhile, the distinct catalytic activities among these amorphous Ni-Fe hydroxide nanostructures prompts us to take notice of the composition of the alloy hydroxides/oxides when studying their catalytic properties, which opens an avenue for the rational design and controllable preparation of such amorphous nanomaterials as advanced OER electrocatalysts.

14.
Nanoscale ; 8(7): 4227-35, 2016 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-26838964

RESUMO

Flexible and transparent supercapacitors, as advanced energy storage devices, are essential for the development of innovative wearable electronics because of their unique optical and mechanical qualities. However, all previous designs are based on carbon-based nanostructures like carbon nanotubes and graphene, and these devices usually have poor or short cycling lives. Here, we demonstrate a high-performance, flexible, transparent, and super-long-life supercapacitor made from ultrafine Co3O4 nanocrystals synthesized using a novel process involving laser ablation in liquid. The fabricated flexible and transparent pseudocapacitor exhibits a high capacitance of 177 F g(-1) on a mass basis and 6.03 mF cm(-2) based on the area of the active material at a scan rate of 1 mV s(-1), as well as a super-long cycling life with 100% retention rate after 20 000 cycles. An optical transmittance of up to 51% at a wavelength of 550 nm is achieved, and there are not any obvious changes in the specific capacitance after bending from 0° to 150°, even after bending over 100 times. The integrated electrochemical performance of the Co3O4-based supercapacitor is greatly superior to that of the carbon-based ones reported to date. These findings open the door to applications of transition metal oxides as advanced electrode materials in flexible and transparent pseudocapacitors.

15.
Sci Rep ; 5: 14184, 2015 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-26373684

RESUMO

Three dimensional Z2 Topological insulator (TI) is an unconventional phase of quantum matter possessing insulating bulk state as well as time-reversal symmetry-protected Dirac-like surface state, which is demonstrated by extensive experiments based on surface sensitive detection techniques. This intriguing gapless surface state is theoretically predicted to exhibit many exotic phenomena when interacting with light, and some of them have been observed. Herein, we report the first experimental observation of novel polarization dependent photocurrent of photodetectors based on the TI Bi2Te3 film under irradiation of linearly polarized light. This photocurrent is linearly dependent on both the light intensity and the applied bias voltage. To pursue the physical origin of the polarization dependent photocurrent, we establish the basic TI surface state model to treat the light irradiation as a perturbation, and we adopt the Boltzmann equation to calculate the photocurrent. It turns out that the theoretical results are in nice qualitative agreement with the experiment. These findings show that the polycrystalline TI Bi2Te3 film working as a multifunctional photodetector can not only detect the light intensity, but also measure the polarization state of the incident light, which is remarkably different from conventional photodetectors that usually only detect the light intensity.

16.
Nanotechnology ; 26(41): 415501, 2015 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-26392266

RESUMO

Amorphous nanomaterials have attracted attention due to their excellent performances, highly comparable to their crystalline counterparts. Sensor materials with amorphous phases are usually evaluated to be unsuitable for sensors because of poor performance. As a matter of fact, amorphous nanomaterials have rather unique sensor behaviors. Here, we report the amorphousization of cobalt monoxide (CoO) nanocrystals driven by a unique process involved in laser ablation in liquid (LAL). We also established that a fast and nonequilibrium process created by LAL results in the amorphousization of nanocrystals. The as-prepared amorphous CoO (a-CoO) nanoflakes possess a high aspect ratio, which showed good sensing of explosive gases. The fabricated gas sensor can detect CO and H2 at levels as low as 5 and 10 ppm, respectively, at 100 °C. The performance characteristics of this sensor, including high sensitivity, low working temperature, and low detection limit, are superior to those of sensors made with crystalline phase oxides. Meanwhile, a temperature-dependent p-n transition was observed in the sensor's response to CO, suggesting that the sensing properties can be tailored by changing the carrier type, thus tuning the selectivity of sensors to different gases. These findings demonstrate the potential applications of amorphous nanomaterials as gas sensor components.

17.
Nanoscale ; 7(36): 14974-81, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26308146

RESUMO

The progress in the field of graphene has aroused a renaissance of keen research interest in layered transition metal dichalcogenides (TMDs). Tungsten disulfide (WS2), a typical TMD with favorable semiconducting band gap and strong light-matter interaction, exhibits great potential for highly-responsive photodetection. However, WS2-based photodetection is currently unsatisfactory due to the low optical absorption (2%-10%) and poor carrier mobility (0.01-0.91 cm(2) V(-1) s(-1)) of the thin WS2 layers grown by chemical vapor deposition (CVD). Here, we introduce pulsed-laser deposition (PLD) to prepare multilayered WS2 films. Large-area WS2 films of the magnitude of cm(2) are achieved. Comparative measurements of a WS2-based photoresistor demonstrate its stable broadband photoresponse from 370 to 1064 nm, the broadest range demonstrated in WS2 photodetectors. Benefiting from the large optical absorbance (40%-85%) and high carrier mobility (31 cm(2) V(-1) s(-1)), the responsivity of the device approaches a high value of 0.51 A W(-1) in an ambient environment. Such a performance far surpasses the CVD-grown WS2-based photodetectors (µA W(-1)). In a vacuum environment, the responsivity is further enhanced to 0.70 A W(-1) along with an external quantum efficiency of 137% and a photodetectivity of 2.7 × 10(9) cm Hz(1/2) W(-1). These findings stress that the PLD-grown WS2 film may constitute a new paradigm for the next-generation stable, broadband and highly-responsive photodetectors.

18.
Sci Rep ; 5: 12320, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26197433

RESUMO

Bismuth (Bi) has undergone researches for dozens of years on account of its abundant physics including the remarkably high mobility, exceptional large positive magnetoresistance and the coexistence of an insulating interior as well as metallic surfaces. Very recently, two-dimensional topologically-protected surface states immune to nonmagnetic perturbation such as surface oxidation and impurity scattering were experimentally demonstrated through systematic magnetotransport measurements, e.g. weak antilocalization effect and angular dependent Shubnikov-de Haas oscillations. Such robust metallic surface states, which are efficient in carrier transportation, along with its small bulk gap (14 meV) make Bi favored for high-responsive broadband photodetection. Here, we for the first time demonstrate the stable ultra-broadband photoresponse from 370 nm to 1550 nm with good reproducibility at room temperature based on a Bi photodetector. The fabricated device's responsivity approaches 250 mA/W, accompanied with a rise time of 0.9 s and a decay time of 1.9 s. The photocurrent is linear dependent on the voltage and incident power, offering good tunability for multi-purpose applications. Thickness-dependent conductance and photocurrent reveal that the bulk is the optically active layer while the surface channel is responsible for carrier transportation. These findings pave an avenue to develop ultra-broadband Bi photodetectors for the next-generation multifunctional optoelectronic devices.

19.
J Fish Biol ; 87(2): 241-55, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26099328

RESUMO

In this study, the full-length complementary (c)DNA of interleukin-1 receptor-associated kinase 1 gene (irak1) was cloned from common carp Cyprinus carpio. The complete open reading frame of irak1 contained 2109 bp encoding a protein of 702 amino acid residues that comprised a death domain, a ProST region, a serine-threonine-specific protein kinase catalytic domain and a C-terminal domain. The amino-acid sequence of C. carpio Irak1 protein shared sequence homology with grass carp Ctenopharyngodon idellus (84.5%). The phylogenetic tree of IRAKs separated the polypeptides into four clades, comprising IRAK1s, IRAK2s, IRAK3s and IRAK4s. Cyprinus carpio Irak1 fell into the cluster with previously reported IRAK1s including teleost Irak1s. The irak1 gene was highly expressed in gills, followed by brain, skin, hindgut, buccal epithelium, spleen, foregut, head kidney and liver, and was expressed at lowest levels in gonad and muscle. The irak1 messenger (m)RNA expression was up-regulated in liver, spleen, head kidney, foregut, hindgut, gills and skin after stimulation with Vibrio anguillarum and poly(I:C), and significantly high up-regulated expression was observed in liver and spleen. These results implied that irak1 might participate in antibacterial and antiviral innate immunity. These findings gave the indications that irak1 may participate in antibacterial and antiviral immunity.


Assuntos
Carpas/genética , Proteínas de Peixes/metabolismo , Imunidade Inata , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Sequência de Aminoácidos , Animais , Infecções Bacterianas/imunologia , Carpas/imunologia , Clonagem Molecular , DNA Complementar/genética , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Quinases Associadas a Receptores de Interleucina-1/genética , Quinases Associadas a Receptores de Interleucina-1/imunologia , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , RNA Mensageiro/metabolismo
20.
Sci Rep ; 5: 11070, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-26076705

RESUMO

In recent years, owing to the significant applications of health monitoring, wearable electronic devices such as smart watches, smart glass and wearable cameras have been growing rapidly. Gas sensor is an important part of wearable electronic devices for detecting pollutant, toxic, and combustible gases. However, in order to apply to wearable electronic devices, the gas sensor needs flexible, transparent, and working at room temperature, which are not available for traditional gas sensors. Here, we for the first time fabricate a light-controlling, flexible, transparent, and working at room-temperature ethanol gas sensor by using commercial ZnO nanoparticles. The fabricated sensor not only exhibits fast and excellent photoresponse, but also shows high sensing response to ethanol under UV irradiation. Meanwhile, its transmittance exceeds 62% in the visible spectral range, and the sensing performance keeps the same even bent it at a curvature angle of 90(o). Additionally, using commercial ZnO nanoparticles provides a facile and low-cost route to fabricate wearable electronic devices.


Assuntos
Monitoramento Ambiental/instrumentação , Poluentes Ambientais/análise , Etanol/análise , Gases/análise , Nanopartículas/química , Óxido de Zinco/química , Monitoramento Ambiental/métodos , Desenho de Equipamento , Humanos , Microeletrodos , Microtecnologia , Nanopartículas/ultraestrutura , Processos Fotoquímicos , Raios Ultravioleta
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