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1.
Small ; : e2400151, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558525

RESUMO

Transparent paper manufactured from wood fibers is emerging as a promising, cost-effective, and carbon-neutral alternatives to plastics. However, fully exploring their mechanical properties is one of the most pressing challenges. In this work, a strong yet tough transparent paper with superior folding endurance is prepared by rationally altering the native fiber structure. Microwave-assisted choline chloride/lactic acid deep eutectic solvent (DES) pulping is first utilized to isolate wood fibers from spruce wood. During this process, the S1 layer within the fibers is partially disrupted, forming protruding microfibrils that play a crucial role in enhancing cellulose accessibility. Subsequently, carboxymethylation treatment is applied to yield uniformly swollen carboxymethylated wood fibers (CM fibers), which improves the interaction between CM fibers during papermaking. The as-prepared transparent paper not only shows a 90% light transmittance (550 nm) but also exhibits impressive mechanical properties, including a folding endurance of over 26 000, a tensile strength of 248.4 MPa, and a toughness of 15.6 MJ m-3. This work provides a promising route for manufacturing transparent paper with superior mechanical properties from wood fibers and can extend their use in areas normally dominated by high-performance nonrenewable plastics.

2.
Hepatology ; 75(3): 584-599, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34687050

RESUMO

BACKGROUND AND AIMS: The mechanisms involved in liver regeneration after partial hepatectomy (pHx) are complicated. Cellular senescence, once linked to aging, plays a pivotal role in wound repair. However, the regulatory effects of cellular senescence on liver regeneration have not been fully elucidated. APPROACH AND RESULTS: Mice subjected to pHx were analyzed 14 days after surgery. The incomplete remodeling of liver sinusoids affected shear stress-induced endothelial nitric oxide synthase (eNOS) signaling on day 14, resulting in the accumulation of senescent LSECs. Removing macrophages to augment LSEC senescence led to a malfunction of the regenerating liver. A dynamic fluctuation in Notch activity accompanied senescent LSEC accumulation during liver regeneration. Endothelial Notch activation by using Cdh5-CreERT NICeCA mice triggered LSEC senescence and senescence-associated secretory phenotype, which disrupted liver regeneration. Blocking the Notch by γ-secretase inhibitor (GSI) diminished senescence and promoted LSEC expansion. Mechanically, Notch-hairy and enhancer of split 1 signaling inhibited sirtuin 1 (Sirt1) transcription by binding to its promoter region. Activation of Sirt1 by SRT1720 neutralized the up-regulation of P53, P21, and P16 caused by Notch activation and eliminated Notch-driven LSEC senescence. Finally, Sirt1 activator promoted liver regeneration by abrogating LSEC senescence and improving sinusoid remodeling. CONCLUSIONS: Shear stress-induced LSEC senescence driven by Notch interferes with liver regeneration after pHx. Sirt1 inhibition accelerates liver regeneration by abrogating Notch-driven senescence, providing a potential opportunity to target senescent cells and facilitate liver repair after injury.


Assuntos
Senescência Celular , Regeneração Hepática , Receptores Notch , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Animais , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Inibidores e Moduladores de Secretases gama/farmacologia , Hepatectomia/métodos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Regeneração Hepática/efeitos dos fármacos , Regeneração Hepática/fisiologia , Camundongos , Óxido Nítrico Sintase Tipo III/metabolismo , Receptores Notch/antagonistas & inibidores , Receptores Notch/metabolismo , Fenótipo Secretor Associado à Senescência/genética
3.
Hepatology ; 76(3): 742-758, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35006626

RESUMO

BACKGROUND AND AIMS: Although NASH can lead to severe clinical consequences, including cirrhosis and hepatocellular carcinoma, no effective treatment is currently available for this disease. Increasing evidence indicates that LSECs play a critical role in NASH pathogenesis; however, the mechanisms involved in LSEC-mediated NASH remain to be fully elucidated. APPROACH AND RESULTS: In the current study, we found that LSEC homeostasis was disrupted and LSEC-specific gene profiles were altered in methionine-choline-deficient (MCD) diet-induced NASH mouse models. Importantly, Notch signaling was found to be activated in LSECs of NASH mice. To then investigate the role of endothelial Notch in NASH progression, we generated mouse lines with endothelial-specific Notch intracellular domain (NICD) overexpression or RBP-J knockout to respectively activate or inhibit Notch signaling in endothelial cells. Notably, endothelial-specific overexpression of the NICD accelerated LSEC maladaptation and aggravated NASH, whereas endothelial cell-specific inhibition of Notch signaling restored LSEC homeostasis and improved NASH phenotypes. Furthermore, we demonstrated that endothelial-specific Notch activation exacerbated NASH by inhibiting endothelial nitric oxide synthase (eNOS) transcription, whereas administration of the pharmacological eNOS activator YC-1 alleviated hepatic steatosis and lipid accumulation resulting from Notch activation. Finally, to explore the therapeutic potential of using Notch inhibitors in NASH treatment, we applied two gamma-secretase inhibitors-DAPT and LY3039478-in an MCD diet-induced mouse model of NASH, and found that both inhibitors effectively ameliorated hepatic steatosis, inflammation, and liver fibrosis. CONCLUSIONS: Endothelial-specific Notch activation triggered LSEC maladaptation and exacerbated NASH phenotypes in an eNOS-dependent manner. Genetic and pharmacological inhibition of Notch signaling effectively restored LSEC homeostasis and ameliorated NASH progression.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Modelos Animais de Doenças , Células Endoteliais/patologia , Endotélio , Fígado/patologia , Cirrose Hepática/complicações , Metionina , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia
4.
Am J Bot ; 110(12): e16253, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37938812

RESUMO

PREMISE: Moss sporophytes differ strongly in size and biomass partitioning, potentially reflecting reproductive and dispersal strategies. Understanding how sporophyte traits are coordinated is essential for understanding moss functioning and evolution. This study aimed to answer: (1) how the size and proportions of the sporophyte differ between moss species with and without a prominent central strand in the seta, (2) how anatomical and morphological traits of the seta are related, and (3) how sporophytic biomass relates to gametophytic biomass and nutrient concentrations. METHODS: We studied the relationships between seta anatomical and morphological traits, the biomass of seta, capsule, and gametophyte, and carbon, nitrogen, and phosphorus concentrations of 27 subtropical montane moss species. RESULTS: (1) Moss species with a prominent central strand in the seta had larger setae and heavier capsules than those without a prominent strand. (2) With increasing seta length, setae became thicker and more rounded for both groups, while in species with a prominent central strand, the ratio of transport-cell area to epidermal area decreased. (3) In both groups, mosses with greater gametophytic biomass tended to have heavier sporophytes, but nitrogen and phosphorus concentrations in the gametophyte were unrelated to sporophytic traits. CONCLUSIONS: Our study highlights that the central strand in the seta may have an important functional role and affect the allometry of moss sporophytes. The coordinated variations in sporophyte morphological and anatomical traits follow basic biomechanical principles of cylinder-like structures, and these traits relate only weakly to the gametophytic nutrient concentrations. Research on moss sporophyte functional traits and their relationships to gametophytes is still in its infancy but could provide important insights into their adaptative strategies.


Assuntos
Briófitas , Bryopsida , Células Germinativas Vegetais , Briófitas/anatomia & histologia , Nitrogênio , Fósforo
5.
Nanotechnology ; 35(4)2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37669634

RESUMO

Two-dimensional transition metal dichalcogenides (TMDs), as flexible and stretchable materials, have attracted considerable attention in the field of novel flexible electronics due to their excellent mechanical, optical, and electronic properties. Among the various TMD materials, atomically thin MoS2has become the most widely used material due to its advantageous properties, such as its adjustable bandgap, excellent performance, and ease of preparation. In this work, we demonstrated the practicality of a stacked wafer-scale two-layer MoS2film obtained by transferring multiple single-layer films grown using chemical vapor deposition. The MoS2field-effect transistor cell had a top-gated device structure with a (PI) film as the substrate, which exhibited a high on/off ratio (108), large average mobility (∼8.56 cm2V-1s-1), and exceptional uniformity. Furthermore, a range of flexible integrated logic devices, including inverters, NOR gates, and NAND gates, were successfully implemented via traditional lithography. These results highlight the immense potential of TMD materials, particularly MoS2, in enabling advanced flexible electronic and optoelectronic devices, which pave the way for transformative applications in future-generation electronics.

6.
Int J Mol Sci ; 24(15)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37569770

RESUMO

Hybrid rice breeding is an important strategy for enhancing grain yield. Breeding high-performance parental lines and identifying combining abilities is a top priority for hybrid breeding. Yuenongsimiao (YNSM) and its derivative variety Yuehesimiao (YHSM) are elite restorer lines with a high ability of fertility restoration, from which 67 derived hybrid combinations have been authorized to different degrees in more than 110 instances in China. In this study, we found that YNSM and YHSM contained three candidate restorer-of-fertility (Rf) genes, Rf3, Rf4, and Rf5/Rf1a, that might confer their restoration ability. Subsequently, we investigated heterosis and combining ability of YNSM and YHSM using 50 F1 hybrids from a 5 × 10 incomplete diallelic mating design. Our results indicated that hybrid combinations exhibited significant genetic differences, and the additive effects of the parental genes played a preponderant role in the inheritance of observed traits. The metrics of plant height (PH), 1000-grain weight (TGW), panicle length (PL), and the number of spikelets per panicle (NSP) were mainly affected by genetic inheritance with higher heritability. Notably, the general combining ability (GCA) of YHSM exhibited the largest positive effect on the number of grains per panicle (NGP), NSP, PL, and TGW. Thus, YHSM had the largest GCA effect on yield per plant (YPP). In addition, the GCA of YNSM exhibited a positive impact on YPP, mainly due to the critical contribution of seed setting percentage (SSP). Moreover, YNSM and YHSM exhibited negative GCA effects on PH, implying that YNSM and YHSM could effectively enhance plant lodging resistance by reducing the plant height of the derived hybrids. Remarkably, among the hybrids, Yuanxiang A/YNSM (YXA/YNSM), Shen 08S/Yuemeizhan (S08S/YMZ), and Quan 9311A/YHSM (Q9311A/YHSM) represent promising new combinations with a higher specific combining ability (SCA) effect value on YPP with a value more than 3.50. Our research thus highlights the promising application for the rational utilization of YNSM and YHSM in hybrid rice breeding.


Assuntos
Oryza , Grão Comestível/genética , Vigor Híbrido/genética , Oryza/genética , Fenótipo , Melhoramento Vegetal
7.
Small ; 18(19): e2200671, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35388977

RESUMO

Lignin colloidal spheres (LCSs) are promising biomaterials for application in drug storage and delivery, pollutant adsorption, and ultraviolet protection due to their biocompatibility, amphiphilicity, and conjugated structure. However, wide size distribution of LCSs greatly limits their performances, especially in many precise and advanced applications. Herein, the fabrication of monodispersed LCSs with tailorable sizes ranging from the nanoscale to microscale is reported. Lignin raw materials are first fractionated by solvent extraction, and then the lignin fraction is used to fabricate monodispersed LCSs by solvent/antisolvent self-assembly. The underlying mechanism for the formation of monodispersed LCS is primarily ascribed to the improved homogeneity of long-range intermolecular forces, especially the electrostatic forces and hydrophobic forces, between lignin molecules. Moreover, by manipulating the short-range order of LCSs, an innovative application of lignin as bio-photonic materials with tunable structural colorations (e.g., red, green, or blue) is demonstrated. This work not only provides deep insight and an effective strategy to eliminate the serious inhomogeneity of LCSs, but also makes lignin resources have great potential as biodegradable and biocompatible photonic materials in diverse advanced optical application fields such as photonic devices, anti-counterfeiting labels, and structural color pigments.


Assuntos
Lignina , Fótons , Adsorção , Lignina/química , Solventes
8.
Langmuir ; 38(42): 12813-12821, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36217773

RESUMO

Solar interfacial evaporation based on wood-derived materials has been considered a promising strategy for desalination and wastewater purification. Herein, we adopted delignified wood (DW) as the water transport substrate and lignosulfonate (LS)-modified narrow-band gap semiconductor nickel disulfide (NiS2) as the light-absorbing agent (LS-NiS2) to fabricate a high-efficiency evaporator (LS-NiS2@DW). On the one hand, the high absorbance (>95%) within a broad wavelength range and excellent photothermal conversion efficiency of LS-NiS2 endow efficient solar energy utilization. On the other hand, the hydrophilicity of DW facilitates water activation, which results in a lower evaporation enthalpy of LS-NiS2@DW (1274.4 kJ kg-1) than that of pure water. By combining LS-NiS2 and DW, LS-NiS2@DW achieved an evaporation rate as high as 2.80 kg m-2 h-1 under one sun irradiation (1 kW m-2), and the evaporation efficiency reached 87.4%. Notably, LS-NiS2@DW exhibits a high evaporation rate (2.42-2.69 kg m-2 h-1) in simulated seawater for 24 h with no salt crystals formed on the surface. Moreover, LS-NiS2@DW shows high antibacterial activity with about 90% reduction in bacterial survival rate. This work could provide new perspectives for the design of a high-efficiency wood-based photothermal evaporator.


Assuntos
Níquel , Madeira , Esterilização , Água/química , Antibacterianos , Dissulfetos
9.
Langmuir ; 38(32): 9955-9966, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35894171

RESUMO

The unbalanced evaporation of solvents in low-temperature sintered inks for printed electronics leads to a series of problems in the actual printing process, including printed pattern distortion, surface cracking, and the coffee ring effect, which has become a serious obstacle to this technique. Here, we present a comprehensive investigation of the influence of the solvent composition, environmental, and sintering conditions on the complicated pattern formation process of reactive silver inks. The results first showed that only inks with a certain wettability of solvents could form well-defined patterns. Then, the solvent composition and ambient humidity can be adjusted to balance the nonequilibrium evaporative flow within the liquid and thus to obtain a flat liquid film. Combined with the rapid UV sintering process, the particle size, porosity, and roughness could be controlled to produce dense and homogeneous silver films. Finally, we successfully printed silver electrodes with a smooth and dense surface (Rqs ∼ 21 nm in 0.8 × 0.8 mm2 area and less than 1% porosity) under an optimized relative humidity (RH) of 50-60% at room temperature with the solvent composition of IPA (isopropanol)/2,3-BD (2,3-butanediol) = 8:2. In addition, we also demonstrated high-performance Pr-IZO (praseodymium-doped indium-zinc oxide) thin film transistors (TFTs) with a mobility (µsat) of 2.14 cm2/V/s and Ion/Ioff ratio of over 107 using source-drain electrodes printed under optimized conditions.

10.
Sensors (Basel) ; 22(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36081002

RESUMO

Visual prostheses, used to assist in restoring functional vision to the visually impaired, convert captured external images into corresponding electrical stimulation patterns that are stimulated by implanted microelectrodes to induce phosphenes and eventually visual perception. Detecting and providing useful visual information to the prosthesis wearer under limited artificial vision has been an important concern in the field of visual prosthesis. Along with the development of prosthetic device design and stimulus encoding methods, researchers have explored the possibility of the application of computer vision by simulating visual perception under prosthetic vision. Effective image processing in computer vision is performed to optimize artificial visual information and improve the ability to restore various important visual functions in implant recipients, allowing them to better achieve their daily demands. This paper first reviews the recent clinical implantation of different types of visual prostheses, summarizes the artificial visual perception of implant recipients, and especially focuses on its irregularities, such as dropout and distorted phosphenes. Then, the important aspects of computer vision in the optimization of visual information processing are reviewed, and the possibilities and shortcomings of these solutions are discussed. Ultimately, the development direction and emphasis issues for improving the performance of visual prosthesis devices are summarized.


Assuntos
Próteses Visuais , Processamento de Imagem Assistida por Computador/métodos , Fosfenos , Visão Ocular , Percepção Visual/fisiologia
11.
Disasters ; 45 Suppl 1: S76-S96, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33538045

RESUMO

The outbreak of Covid-19 in China during the Spring Festival of 2020 has changed life as we knew it. To explore its impact on China's economy, we analyse the daily railway passenger volume data during the Spring Festival travel rush and establish two RegARMA models to predict GDP in the first quarter. The models forecast China might lose 4.8 trillion yuan in the first quarter of 2020 due to Covid-19, an expected decrease of 20.69 percent (year-on-year drop 15.60 percent). However, comparing our forecast GDP without Covid-19 (23.2 trillion yuan) with the real GDP (20.65 trillion yuan), there is a smaller drop of 2.55 trillion yuan, a gap of 12.35 percent. The reason for this overestimation is that some positive factors, including macro-control policies, are neglected in these models. With the global spread of Covid-19, China should adopt a policy of focusing on balancing both domestic and external affairs against the instability of the world economy.


Assuntos
COVID-19 , China/epidemiologia , Humanos , SARS-CoV-2 , Meios de Transporte , Viagem
12.
Biomacromolecules ; 21(4): 1560-1567, 2020 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-32150393

RESUMO

Biodegradable and renewable materials, such as cellulose nanomaterials, have been studied as a replacement material for traditional plastics in the biomedical field. Furthermore, in chronic wound care, modern wound dressings, hydrogels, and active synthetic extracellular matrices promoting tissue regeneration are developed to guide cell growth and differentiation. Cells are guided not only by chemical cues but also through their interaction with the surrounding substrate and its physicochemical properties. Hence, the current work investigated plant-based cellulose nanomaterials and their surface characteristic effects on human dermal fibroblast (HDF) behavior. Four thin cellulose nanomaterial-based coatings produced from microfibrillar cellulose (MFC), cellulose nanocrystals (CNC), and two TEMPO-oxidized cellulose nanofibers (CNF) with different total surface charge were characterized, and HDF viability and adhesion were evaluated. The highest viability and most stable adhesion were on the anionic CNF coating with a surface charge of 1.14 mmol/g. On MFC and CNC coated surfaces, HDFs sedimented but were unable to anchor to the substrate, leading to low viability.


Assuntos
Nanofibras , Nanopartículas , Nanoestruturas , Celulose , Fibroblastos , Humanos
13.
Langmuir ; 35(14): 4834-4842, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30892906

RESUMO

Flexible and highly sensitive humidity sensors are crucial for humidity detection. In this study, a flexible cellulose nanofiber/carbon nanotube (NFC/CNT) humidity sensor with high sensitivity performance was developed via fast vacuum filtration. CNTs were well dispersed in water by using 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO)-oxidized NFC as a dispersant. More importantly, NFC also acted as a humidity sensitive material, achieving superior performance of NFC/CNT humidity sensors. The obtained NFC/CNT humidity sensor with 5 wt % CNT loading exhibits outstanding sensitive performance, and its response value reaches a maximum of 69.9% (Δ I/ I0) at 95% relative humidity (RH). It also displays good bending resistance and long-term stability. In addition, the NFC/CNT humidity sensor was employed to monitor human breath. Therefore, we believe that the flexible, highly sensitive, and simply designed NFC/CNT humidity sensor is a promising candidate for various applications in the field of humidity measurement.

14.
Biomacromolecules ; 20(12): 4466-4475, 2019 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-31710481

RESUMO

Simultaneous production and functionalization of cellulose nanofibrils (CNFs) for heavy metal ion removal is an economical and promising solution to expedite their use in water treatment. In this work, carboxymethylated CNFs (CMCNFs) with a carboxylate content up to 2.7 mmol/g are prepared by a combination of carboxymethylation and homogenization, which show diameters of 3.40-3.53 nm and lengths of 1210.6-383.3 nm. The effect of experimental conditions (including pH, carboxylate content, contact time, initial Cu2+ concentration) on the removal performance of CMCNFs for Cu2+ is investigated in detail. Adsorption performances of CMCNFs present a record high equilibrium Cu2+ removal capacity of 115.3 mg/g at pH 5.0. Additionally, the underlying mechanism for the removal of Cu2+ ions was uncovered by coupling the fitting results based on pseudo-second-order kinetic and Langmuir isotherm models with various characterizations such as scanning electron microscopy, energy dispersive spectroscopy (EDS), EDS mapping, X-ray photoelectron spectroscopy, atomic force microscopy, and powder X-ray diffraction. Finally, the potential application of CMCNF-2.7 with high carboxylate content in converting copper-contaminated water into drinking water was demonstrated. CMCNFs provide a new selection for the design of novel nanocellulose-based materials for water treatments.


Assuntos
Carboximetilcelulose Sódica/química , Cobre/química , Nanofibras/química , Purificação da Água , Água/química , Nanofibras/ultraestrutura
15.
J Nanosci Nanotechnol ; 19(7): 4305-4309, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30765010

RESUMO

In this paper, flowerlike nickel sulfide materials are synthesized using a facile solution-phase biomolecule-assisted approach in the presence of L-cysteine (an ordinary and cheap amino acid), which turned out to serve as both the sulfur source and the directing molecule in the formation of nickel sulfide nanostructures. The morphology, structure, and phase composition of the assynthesized nickel sulfide products are characterized using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Raman. Moreover, the nickel sulfide materials are investigated as electro catalysts for hydrogen evolution reaction (HER) in strongly alkaline media. The electro catalytic performance of as-prepared nickel sulfide is promising for applications as non-noble-metal HER catalysts with water splitting for hydrogen production.

16.
Molecules ; 24(1)2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30609869

RESUMO

Heat-shock protein 70 (HSP70) is a molecular chaperone that plays critical roles in cell protein folding and metabolism, which helps to protect cells from unfavorable environmental stress. Haliotis diversicolor is one of the most important economic breeding species in the coastal provinces of south China. To date, the expression and transcriptional regulation of HSP70 in Haliotis diversicolor (HdHSP70) has not been well characterized. In this study, the expression levels of HdHSP70 gene in different tissues and different stress conditions were detected. The results showed that the HdHSP70 gene was ubiquitously expressed in sampled tissues and was the highest in hepatopancreas, followed by hemocytes. In hepatopancreas and hemocytes, the HdHSP70 gene was significantly up-regulated by Vibrio parahaemolyticus infection, thermal stress, and combined stress (Vibrio parahaemolyticus infection and thermal stress combination), indicating that HdHSP70 is involved in the stress response and the regulation of innate immunity. Furthermore, a 2383 bp of 5'-flanking region sequence of the HdHSP70 gene was cloned, and it contains a presumed core promoter region, a CpG island, a (TG)39 simple sequence repeat (SSR), and many potential transcription factor binding sites. The activity of HdHSP70 promoter was evaluated by driving the expression of luciferase gene in HEK293FT cells. A series of experimental results indicated that the core promoter region is located between -189 bp and +46 bp, and high-temperature stress can increase the activity of HdHSP70 promoter. Sequence-consecutive deletions of the luciferase reporter gene in HEK293FT cells revealed two possible promoter activity regions. To further identify the binding site of the key transcription factor in the two regions, two expression vectors with site-directed mutation were constructed. The results showed that the transcriptional activity of NF-1 site-directed mutation was significantly increased (p < 0.05), whereas the transcriptional activity of NF-κB site-directed mutation was significantly reduced. These results suggest that NF-1 and NF-κB may be two important transcription factors that regulate the expression of HdHSP70 gene.


Assuntos
Gastrópodes/genética , Gastrópodes/microbiologia , Proteínas de Choque Térmico HSP70/genética , Estresse Fisiológico/genética , Temperatura , Vibrioses/veterinária , Vibrio parahaemolyticus/fisiologia , Regiões 5' não Traduzidas , Animais , Sequência de Bases , Clonagem Molecular , Biologia Computacional/métodos , Expressão Gênica , Regulação da Expressão Gênica , Genes Reporter , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Mutação , Regiões Promotoras Genéticas , Fatores de Transcrição/metabolismo , Transcrição Gênica
17.
Soft Matter ; 14(46): 9402-9410, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30421779

RESUMO

Ultrashort channels of electrodes are essential for the construction of advanced functional devices with high-level integration and high operation speed. However, the channel length of fabricated electrodes is limited to 20 µm in inkjet printing. Although several methods have been previously proposed to obtain short channels, they require extra processing steps. In this paper, channel self-aligning phenomenon was observed in directly patterned electrodes on unmodified substrate by inkjet printing, when using an interspace defects growing method. Further exploring the underlying mechanism reveals that the capillary force induced air film prevents droplets coalescence, even on a substrate with no temperature differences. The wetting region, which is generated by the receding droplets impingement, will draw droplets closer together at a larger drop space, thus demanding smaller air pressure for coalescence inhibition and contributing to the self-aligning phenomenon of micro-sized droplets released by inkjet printing. Accordingly, an ultrashort channel of 2.38 µm is obtained with relatively smooth boundaries, when electrodes are printed on a slightly heated substrate, which reduces the air pressure between two neighboring droplets. This work will provide a significant reference for future high resolution applications of inkjet printing technology.

18.
Chem Rev ; 116(16): 9305-74, 2016 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-27459699

RESUMO

With the arising of global climate change and resource shortage, in recent years, increased attention has been paid to environmentally friendly materials. Trees are sustainable and renewable materials, which give us shelter and oxygen and remove carbon dioxide from the atmosphere. Trees are a primary resource that human society depends upon every day, for example, homes, heating, furniture, and aircraft. Wood from trees gives us paper, cardboard, and medical supplies, thus impacting our homes, school, work, and play. All of the above-mentioned applications have been well developed over the past thousands of years. However, trees and wood have much more to offer us as advanced materials, impacting emerging high-tech fields, such as bioengineering, flexible electronics, and clean energy. Wood naturally has a hierarchical structure, composed of well-oriented microfibers and tracheids for water, ion, and oxygen transportation during metabolism. At higher magnification, the walls of fiber cells have an interesting morphology-a distinctly mesoporous structure. Moreover, the walls of fiber cells are composed of thousands of fibers (or macrofibrils) oriented in a similar angle. Nanofibrils and nanocrystals can be further liberated from macrofibrils by mechanical, chemical, and enzymatic methods. The obtained nanocellulose has unique optical, mechanical, and barrier properties and is an excellent candidate for chemical modification and reconfiguration. Wood is naturally a composite material, comprised of cellulose, hemicellulose, and lignin. Wood is sustainable, earth abundant, strong, biodegradable, biocompatible, and chemically accessible for modification; more importantly, multiscale natural fibers from wood have unique optical properties applicable to different kinds of optoelectronics and photonic devices. Today, the materials derived from wood are ready to be explored for applications in new technology areas, such as electronics, biomedical devices, and energy. The goal of this study is to review the fundamental structures and chemistries of wood and wood-derived materials, which are essential for a wide range of existing and new enabling technologies. The scope of the review covers multiscale materials and assemblies of cellulose, hemicellulose, and lignin as well as other biomaterials derived from wood, in regard to their major emerging applications. Structure-properties-application relationships will be investigated in detail. Understanding the fundamental properties of these structures is crucial for designing and manufacturing products for emerging applications. Today, a more holistic understanding of the interplay between the structure, chemistry, and performance of wood and wood-derived materials is advancing historical applications of these materials. This new level of understanding also enables a myriad of new and exciting applications, which motivate this review. There are excellent reviews already on the classical topic of woody materials, and some recent reviews also cover new understanding of these materials as well as potential applications. This review will focus on the uniqueness of woody materials for three critical applications: green electronics, biological devices, and energy storage and bioenergy.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Química Verde , Madeira/química , Celulose/química , Equipamentos e Provisões Elétricas , Hidrogéis , Dispositivos Lab-On-A-Chip , Lignina/química , Membranas Artificiais , Nanofibras/química , Papel , Polissacarídeos/química , Porosidade , Energia Renovável
19.
J Nanosci Nanotechnol ; 18(10): 7090-7094, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29954538

RESUMO

In recent years, conductive paper made of graphene and cellulose fibers has triggered a great deal of attention due to its scalable fabrication process, low cost, and environmentally friendliness. However, poor mechanical properties limit its commercial applications. In this study, conductive graphene/cellulose paper with improved elastic modulus and desirable conductivity was achieved by chemically modifying the surface properties of natural cellulose fibers using aqueous 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidation system. The effect of the carboxyl content on the mechanical properties and conductivity of graphene/cellulose paper was studied in detail. The results showed that the carboxyl content of cellulose had a significant impact on the mechanical properties of graphene/cellulose paper. At low carboxyl content (0.42 mmol/g), the elastic modulus of the graphene/oxidized-cellulose conductive paper achieved the value of 1572 MPa, which was 27.4% larger than that of cellulose/graphene conductive paper. Meanwhile, the as-prepared paper exhibited excellent conductive properties, and its sheet resistance was only 78.57 Ω/sq.

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