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1.
Nano Lett ; 24(6): 1959-1966, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38294858

RESUMEN

Overall water splitting, as a critical approach to producing green hydrogen, is greatly impeded by the mass transfer of gaseous bubbles and dissolved gas molecules. Herein, a bifunctional superaerophilic/superaerophobic (SAL/SAB) NiFe layered-double-hydroxides (LDHs) electrode has been developed, which can drive H2 and O2 bubbles out of the reaction system by asymmetric Laplace pressure and accelerate dissolved gases diffusion through reducing their diffusion distance. Consequently, the SAL/SAB NiFe-LDHs electrode exhibits excellent HER activity with an overpotential of -76 mV at -10 mA cm-2 and outstanding oxygen evolution reaction activity with an overpotential of 253 mV at 100 mA cm-2. The bifunctional SAL/SAB NiFe-LDHs electrode is further utilized in overall water splitting, which can achieve 10 mA cm-2 with a cell voltage of 1.54 V. This work provides an efficient strategy to improve the efficiency of overall water splitting and can stimulate new electrode design in various gas-involved processes.

2.
Appl Environ Microbiol ; 90(4): e0023924, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38483156

RESUMEN

What is the effect of phyllosphere microorganisms on litter decomposition in the absence of colonization by soil microorganisms? Here, we simulated the litter standing decomposition stage in the field to study the differences in the composition and structure of the phyllosphere microbial community after the mixed decomposition of Populus × canadensis and Pinus sylvestris var. mongolica litter. After 15 months of mixed decomposition, we discovered that litters that were not in contact with soil had an antagonistic effect (the actual decomposition rate was 18.18%, which is lower than the expected decomposition rate) and the difference between the litters themselves resulted in a negative response to litter decomposition. In addition, there was no significant difference in bacterial and fungal community diversity after litter decomposition. The litter bacterial community was negatively responsive to litter properties and positively responsive to the fungal community. Importantly, we found that bacterial communities had a greater impact on litter decomposition than fungi. This study has enriched our understanding of the decomposition of litter itself and provided a theoretical basis for further exploring the "additive and non-additive effects" of litter decomposition and the mechanism of microbial drive. IMPORTANCE: The study of litter decomposition mechanism plays an important role in the material circulation of the global ecosystem. However, previous studies have often looked at contact with soil as the starting point for decomposition. But actually, standing litter is very common in forest ecosystems. Therefore, we used field simulation experiments to simulate the decomposition of litters without contact with soil for 15 months, to explore the combined and non-added benefits of the decomposition of mixed litters, and to study the influence of microbial community composition on the decomposition rate while comparing the differences of microbial communities.


Asunto(s)
Ecosistema , Microbiota , Suelo/química , Microbiología del Suelo , Hojas de la Planta , Bosques , Bacterias
3.
Phys Chem Chem Phys ; 26(5): 4429-4436, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38240037

RESUMEN

Most tough elastomer composites are reinforced by introducing sacrificial structures and fillers. Understanding the contribution of fillers and sacrificial bonds in elastomer composites to the energy dissipation is critical for the design of high-toughness materials. However, the energy dissipation mechanism in elastomer composites remains elusive. In this study, using a tearing test and time-temperature superposition, we investigate the effect of fillers and sacrificial bonds on the energy dissipation of elastomer composites consisting of poly(lipoic acid)/silver-coated Al fillers. We found that the fillers and sacrificial bonds mutually enhance both the intrinsic fracture energy and the bulk energy dissipation, and moreover the sacrificial bonds play a more important role in enhancing fracture toughness than the fillers. It is unreasonable to rely solely on the loss factor for bulk energy dissipation. The addition of sacrificial bonds results in a chain segment experiencing greater binding force compared to the addition of fillers. This suggests that the chain segment consumes more energy during its movement. By calculating the length of the Kuhn chain segment and the Kuhn number, it is evident that the addition of sacrificial bonds results in a greater binding force for the chain segment than the addition of fillers, and this enhanced binding force increases the energy consumption during the motion of the chain segment.

4.
Nano Lett ; 23(23): 11043-11050, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38032845

RESUMEN

Layered MXene nanofluidic membranes still face the problems of low mechanical property, poor ion selectivity, and low output power density. In this work, we successfully constructed heterostructured membranes with the combination of the layered channels of the MXene layer on the top and the nanoscale poly(p-phenylene-benzodioxazole) nanofiber (PBONF) layer on the bottom through a stepwise filtration method. The as-prepared MXene/PBONF-50 heterogeneous membrane exhibits high mechanical properties (strength of 221.6 MPa, strain of 3.2%), high ion selectivity of 0.87, and an excellent output power density of 15.7 W/m2 at 50-fold concentration gradient. Excitingly, the heterogeneous membrane presents a high power density of 6.8 W/m2 at a larger testing area of 0.79 mm2 and long-term stability. This heterogeneous membrane construction provides a viable strategy for the enhancement of mechanical properties and osmotic energy conversion of 2D materials.

5.
Neurourol Urodyn ; 41(5): 1177-1184, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35481613

RESUMEN

AIM: To evaluate lower urinary tract symptoms (LUTS) in children with infantile-onset Pompe disease (IOPD) who received early treatment. METHODS: Pompe disease (PD), or glycogen storage disease II is a rare autosomal recessive lysosomal storage disease that affects multiple organ systems. To our knowledge, only one study has focused on the relationship between LUTS and incontinence in children with PD. This cross-sectional study was conducted from August 2019 through March 2021 and children with IOPD, who had received early and regular enzyme replacement therapy, were enrolled. Participants or their parents completed the Dysfunctional Voiding Scoring System (DVSS) questionnaire. All children underwent uroflowmetry and postvoid residual urine measurements. Fourteen children (age, 4-9 years) with IOPD were enrolled. RESULTS: Ten patients (71.4%) had abnormal uroflow curves. In addition, results of the DVSS revealed that approximately half (42.9%) of our IOPD patients had voiding dysfunction, with urinary incontinence as the most common symptom (64.3%, 9/14). No significant correlations were found between LUTS and uroflow curves in children with IOPD. CONCLUSIONS: The frequency of LUTS and lower urinary tract dysfunction noted on uroflowmetry should encourage pediatricians to actively identify IOPD patients with LUTS, regardless of the timing and frequency of their treatments, and refer them to a urologist for further evaluation and appropriate treatment.


Asunto(s)
Enfermedad del Almacenamiento de Glucógeno Tipo II , Síntomas del Sistema Urinario Inferior , Incontinencia Urinaria , Niño , Preescolar , Estudios Transversales , Enfermedad del Almacenamiento de Glucógeno Tipo II/tratamiento farmacológico , Enfermedad del Almacenamiento de Glucógeno Tipo II/epidemiología , Humanos , Síntomas del Sistema Urinario Inferior/diagnóstico , Síntomas del Sistema Urinario Inferior/epidemiología , Síntomas del Sistema Urinario Inferior/etiología , Prevalencia , Vejiga Urinaria , Incontinencia Urinaria/epidemiología , Incontinencia Urinaria/etiología
6.
Compr Rev Food Sci Food Saf ; 21(2): 1732-1776, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35142435

RESUMEN

Food-derived bioactive peptides (BAPs) are recently utilized as functional food raw materials owing to their potential health benefits. Although there is a huge amount of scientific research about BAPs' identification, purification, characterization, and physiological functions, and subsequently, many BAPs have been marketed, there is a paucity of review on the regulatory requirements, bioavailability, and safety of BAPs. Thus, this review focuses on the toxic peptides that could arise from their primary proteins throughout protein extraction, protein pretreatment, and BAPs' formulation. Also, the influences of BAPs' length and administration dosage on safety are summarized. Lastly, the challenges and possibilities in BAPs' bioavailability and regulatory requirements in different countries were also presented. Results revealed that the human studies of BAPs are essential for approvals as healthy food and to prevent the consumers from misinformation and false promises. The BAPs that escape the gastrointestinal tract epithelium and move to the stomach are considered good peptides and get circulated into the blood using different pathways. In addition, the hydrophobicity, net charge, molecular size, length, amino acids composition/sequences, and structural characteristics of BAPs are critical for bioavailability, and appropriate food-grade carriers can enhance it. The abovementioned features are also vital to optimize the solubility, water holding capacity, emulsifying ability, and foaming property of BAPs in food products. In the case of safety, the possible allergenic and toxic peptides often exhibit physiological functions and could be produced during the hydrolysis of food proteins. It was also noted that the production of iso-peptides bonds and undesirable Maillard reaction might occur during protein extraction, sample pretreatments, and peptide synthesis.


Asunto(s)
Péptidos , Disponibilidad Biológica , Humanos , Péptidos/química
7.
Acta Biochim Biophys Sin (Shanghai) ; 53(9): 1198-1206, 2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34327529

RESUMEN

Breast cancer is the most prevalent malignancy among women worldwide. Paclitaxel (Taxol) is a widely applied chemotherapeutic agent against breast cancer. Although Taxol therapy has achieved improvements recently, development of chemoresistance of breast cancer patients is a major obstacle, leading to therapeutic failure. Long non-coding RNAs (lncRNAs) play pivotal roles in tumorigenesis and progresses of breast cancer. However, the biological roles and molecular targets of lncRNA NEAT1 in Taxol-resistant breast cancer remain unclear. Here, we report that NEAT1 is significantly upregulated in breast tumors and cell lines. In addition, silencing NEAT1 effectively sensitizes breast cancer cells to Taxol. Bioinformatical analysis and luciferase assay demonstrated that miR-23a-3p could be sponged and downregulated by NEAT1. We demonstrated that miR-23a-3p was downregulated and functioned as a tumor suppressor in breast cancer. Furthermore, in the established Taxol-resistant MDA-MB-231 breast cancer cell line, we detected significantly increased NEAT1 expression and downregulated miR-23a-3p expression. Importantly, FOXA1 was identified and validated as a direct target of miR-23a-3p in breast cancer cells. Rescue experiments demonstrated that the restoration of miR-23a-3p in NEAT1-overexpressing Taxol-resistant breast cancer cells successfully overcame the NEAT1-promoted Taxol resistance. Taken together, our results revealed the clinical roles and molecular mechanisms for the NEAT1-mediated chemoresistance, providing new insights into the development of non-coding RNA-based therapeutic strategies for enhancing the anti-cancer effects of traditional chemotherapeutic drugs.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Resistencia a Antineoplásicos , Factor Nuclear 3-alfa del Hepatocito/metabolismo , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Adulto , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Regulación hacia Abajo/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , Factor Nuclear 3-alfa del Hepatocito/genética , Humanos , MicroARNs/genética , Persona de Mediana Edad , Paclitaxel/farmacología , ARN Largo no Codificante/genética , Regulación hacia Arriba/genética , Adulto Joven
8.
Int J Mol Sci ; 22(14)2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-34299179

RESUMEN

The exploitation of new methods to control material structure has historically been dominating the material science. The bottom-up self-assembly strategy by taking atom/molecule/ensembles in nanoscale as building blocks and crystallization as a driving force bring hope for material fabrication. DNA-grafted nanoparticle has emerged as a "programmable atom equivalent" and was employed for the assembly of hierarchically ordered three-dimensional superlattice with novel properties and studying the unknown assembly mechanism due to its programmability and versatility in the binding capabilities. In this review, we highlight the assembly strategies and rules of DNA-grafted three-dimensional superlattice, dynamic assembly by different driving factors, and discuss their future applications.


Asunto(s)
ADN/química , Nanoestructuras/química , Cristalización , Nanotecnología/métodos , Conformación de Ácido Nucleico
9.
BMC Microbiol ; 20(1): 67, 2020 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-32216749

RESUMEN

BACKGROUND: Daqu, the saccharification, fermentation, and aroma-producing agents for Baijiu brewing, is prepared using a complex process. Aging is important for improving the quality of Daqu, but its impact has rarely been studied. This study investigated changes in the physicochemical properties, flavor compounds, and microbial communities during aging of Daqu with a roasted sesame-like flavor. RESULTS: The physicochemical properties changed continuously during aging to provide a high esterifying activity. Aging removed unpleasant flavor compounds and helped to stabilize the flavor compounds in mature Daqu. A high-throughput sequencing approach was used to analyze the changing composition of the microbial communities during aging. Aging helped to modify the microbial population to produce better Baijiu by eliminating low-abundance microbial communities and optimizing the proportion of predominant microbial communities. Nine genera of prokaryotic microbes formed the core microbiota in Daqu after aging. Regarding eukaryotic microbes, Zygomycota, the predominant community, increased in the first 2 months, then decreased in the third month of aging, while Ascomycota, the subdominant community, showed the opposite behavior. Absidia, Trichocomaceae_norank and Rhizopus were the predominant genera in the mature Daqu. CONCLUSIONS: Significant correlations between microbiota and physicochemical properties or flavor compounds were observed, indicating that optimizing microbial communities is essential for aging Daqu. This study provides detailed information on aging during Daqu preparation.


Asunto(s)
Bebidas Alcohólicas/microbiología , Ascomicetos/clasificación , Bacterias/clasificación , Aromatizantes/análisis , Bebidas Alcohólicas/análisis , Ascomicetos/aislamiento & purificación , Bacterias/aislamiento & purificación , Industria de Alimentos , Microbiología de Alimentos , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Análisis de Secuencia de ADN
10.
J Chem Phys ; 152(18): 184903, 2020 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-32414246

RESUMEN

Transport and separation of binary mixtures of active and passive particles are investigated in the presence of temperature differences. It is found that temperature differences can strongly affect the rectification and separation of the mixtures. For active particles, there exists an optimal temperature difference at which the rectified efficiency is maximal. Passive particles are not propelled and move by collisions with active particles, so the response to temperature differences is more complicated. By changing the system parameters, active particles can change their directions, while passive particles always move in the same direction. The simulation results show that the separation of mixtures is sensitive to the system parameters, such as the angular velocity, the temperature difference, and the polar alignment. The mixed particles can be completely separated under certain conditions.

11.
Nanomedicine ; 24: 102105, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31740406

RESUMEN

PEG coating was regarded as one effective method to improve the tumor-targeting efficiency of hyaluronic acid-based nanoparticles (HBN). However, the research of interaction between PEG coating and different receptors such as stabilin-2 and CD44 was limited. Herein, we synthesized a series of PEGylated hyaluronic acid with Curcumin (PHCs) to evaluate the role of PEG coating density in the interaction between HA and its receptors, which influenced tissues targeting activity, pharmacokinetic profiles and therapeutic efficacy of HBN. Compared with other counterparts, PHC HBN with about 5% PEG coating density preferably accumulated in the tumor mass, rather than in the liver, and hold desirable anti-cancer effect. These results indicated that to obtain optimized anticancer effect of HBN, the cellular uptake efficiency between different types of the cells should be carefully balanced by different PEG densities.


Asunto(s)
Curcumina , Sistemas de Liberación de Medicamentos , Receptores de Hialuranos/metabolismo , Nanopartículas , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentales , Animales , Curcumina/química , Curcumina/farmacocinética , Curcumina/farmacología , Femenino , Ácido Hialurónico/química , Ácido Hialurónico/farmacocinética , Ácido Hialurónico/farmacología , Hígado/metabolismo , Hígado/patología , Ratones , Ratones Endogámicos BALB C , Células 3T3 NIH , Nanopartículas/química , Nanopartículas/uso terapéutico , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Polietilenglicoles/química , Polietilenglicoles/farmacocinética , Polietilenglicoles/farmacología
12.
Sensors (Basel) ; 20(23)2020 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-33287133

RESUMEN

Biosensors are small but smart devices responding to the external stimulus, widely used in many fields including clinical diagnosis, healthcare and environment monitoring, etc. Moreover, there is still a pressing need to fabricate sensitive, stable, reliable sensors at present. DNA origami technology is able to not only construct arbitrary shapes in two/three dimension but also control the arrangement of molecules with different functionalities precisely. The functionalization of DNA origami nanostructure endows the sensing system potential of filling in weak spots in traditional DNA-based biosensor. Herein, we mainly review the construction and sensing mechanisms of sensing platforms based on DNA origami nanostructure according to different signal output strategies. It will offer guidance for the application of DNA origami structures functionalized by other materials. We also point out some promising directions for improving performance of biosensors.


Asunto(s)
Técnicas Biosensibles , ADN , Nanoestructuras , Nanotecnología , Conformación de Ácido Nucleico
13.
Chin J Traumatol ; 23(1): 20-24, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32081450

RESUMEN

PURPOSE: The purpose of this study was to review the microsurgical anatomy and clipping of ruptured anterior communicating artery (AComA) aneurysms and to plan and avoid complications before operation. METHODS: A total of 523 cases of cerebral aneurysms admitted to the neurosurgery department of the Third Affiliated Hospital of Sun Yat-Sen University from September 2010 to October 2018 were analyzed retrospectively. Among them, 85 patients had ruptured AComA aneurysms. This study was limited to 85 of these cases, whose satisfactory preoperative angiographic diagnostic films can be retrieved from the hospital database system because of the need for detailed review. RESULTS: We performed supraorbital eyebrow keyhole approach (SOEK) craniotomy in 85 patients to clip 85 AComA aneurysms, in the setting of subarachnoid hemorrhage (SAH). Patients' mean age was (52.69 ± 9.94) years (range, 28-78 years). The proportions of small, medium and large aneurysms were 83.5%, 15.3%, and 1.2%, respectively. The average size of the aneurysms was (5.07 ± 2.36) mm. There were 77.8% of patients with inferior aneurysms and 81.3% of patients with superior aneurysms achieved good results. There was a significant correlation between A1 dominance and operation method (p < 0.001). There was no significant relationship between surgical approach and aneurysm projection or A2 plane (p = 0.157 &p = 0.318). CONCLUSION: Regardless of whether the A2 plane is open or closed, the A1 dominant side is still a better choice for accessing AComA aneurysms to avoid dangerous premature bleeding.


Asunto(s)
Craneotomía/métodos , Hemorragia Subaracnoidea/cirugía , Procedimientos Quirúrgicos Vasculares/métodos , Adulto , Anciano , Femenino , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Hemorragia Subaracnoidea/etiología
14.
BMC Biotechnol ; 19(1): 51, 2019 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-31345213

RESUMEN

BACKGROUND: A mesophilic xylanase PjxA from Penicillium janthinellum MA21601 has high specific activity under acidic condition and holds great potential for applications in the animal feed industry. To enhance the thermostability of xylanase PjxA, two mutation strategies in the N-terminal region were examined and then integrated into the xylanase to further improvement. The recombinant xylanase PTxA-DB (The meaning of DB is disulfide-bridge.) was constructed by replacement of five residues in the mutated region in TfxA (T10Y, N11H, N12D, Y15F, N30 L), combined with an additional disulfide bridge in the N-terminal region. RESULTS: The Tm value of mutant PTxA-DB was improved from 21.3 °C to 76.6 °C, and its half-life was found to be 53.6 min at 60 °C, 107-fold higher than the wild type strain. The location of the disulfide bridge (T2C-T29C) was between the irregular loop and the ß-strand A2, accounting for most of the improvement in thermostability of PjxA. Further analysis indicated T2C, T29C, N30 L and Y15F lead to increase N-terminal hydrophobicity. Moreover, the specific activity and substrate affinity of PTxA-DB were also enhanced under the acidic pH values. CONCLUSIONS: These results indicated PTxA-DB could be a prospective additive to industrial animal feeds.


Asunto(s)
Endo-1,4-beta Xilanasas/genética , Proteínas Fúngicas/genética , Mutagénesis , Penicillium/genética , Aminoácidos/química , Aminoácidos/genética , Aminoácidos/metabolismo , Disulfuros/química , Endo-1,4-beta Xilanasas/química , Endo-1,4-beta Xilanasas/metabolismo , Estabilidad de Enzimas/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Modelos Moleculares , Mutación , Penicillium/enzimología , Conformación Proteica , Ingeniería de Proteínas/métodos , Temperatura
15.
J Food Sci Technol ; 56(1): 340-349, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30728576

RESUMEN

The effects of water-extractable arabinoxylans (WEAXs) with different molecular weights on the physicochemical properties and structure of wheat gluten were studied, a transition between ß-turns in ß-leaves in the structure of gluten has been demonstrated by Fourier transform infrared spectroscopy when WEAX samples were added. The ratio of weakly hydrogen-bonded ß-sheets to strongly hydrogen-bonded ß-sheets tended to decrease with increasing WEAX content. FT-Raman analysis demonstrated other changes in the structure of gluten concerning ß-structures, the conformation of the disulfide bridges, and aromatic amino acid environments; these changes were dependent on the molecular weight of the WEAX. Native WEAXs of different molecular weights that are present as discrete fragments of the cell wall have had a negative effect on the properties of gluten. However, low molecular weight WEAX has helped gluten maintain the left-left conformation of its disulfide bonds. In addition, the gluten elasticity was reduced by the native WEAX to make it softer, but the WEAX low molecular weight impeded this process and improved the gluten network.

16.
Small ; 13(40)2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28845917

RESUMEN

Whelk-like polypyrrole (PPy) arrays film is successfully prepared by electropolymerization of pyrrole in the presence of low-surface-energy tetraethylammonium perfluorooctanesulfonate (TEAPFOS) as dopant. The underwater wettability of PPy whelk-like arrays can be successfully tuned by electrical doping/dedoping of PFOS ions. Interestingly, CCl4 droplets with microliter-size as a representative sample are gathered together to form a larger droplet underwater at the potential of +0.8 V (vs Ag/AgCl), because PPy is in its PFOS-doped states. Note that CCl4 droplet can climb uphill successfully on the inclined whelk-like arrays PPy film under the applied potential of -1.0 V (vs Ag/AgCl), which may be attributed to wettability gradient derived from different oxidation states of PPy induced by electrochemical potential. These results may provide a simple strategy for on-demand manipulation of organic droplets underwater at low voltage.

17.
J Chem Phys ; 146(20): 203319, 2017 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-28571335

RESUMEN

Understanding and controlling the glass transition temperature (Tg) and dynamics of polymers in confined geometries are of significance in both academia and industry. Here, we investigate how the thermal stress induced by a mismatch in the coefficient of thermal expansion affects the Tg behavior of polystyrene (PS) nanorods located inside cylindrical alumina nanopores. The size effects and molecular weight dependence of the Tg are also studied. A multi-step relaxation process was employed to study the relationship between thermal stress and cooling rate. At fast cooling rates, the imparted thermal stress would overcome the yield stress of PS and peel chains off the pore walls, while at slow cooling rates, chains are kept in contact with the pore walls due to timely dissipation of the produced thermal stress during vitrification. In smaller nanopores, more PS chains closely contact with pore walls, then stronger internal thermal stress would be generated between core and shell of PS nanorod, which results in a larger deviation between two Tgs. The core part of PS shows lower Tg than bulk value, which can induce faster dynamics in the center region. A complex and important role stress plays is supposed in complex confinement condition, e.g., in nanopores, during vitrification.

18.
J Food Sci Technol ; 54(2): 469-480, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28242946

RESUMEN

The effect of bovine serum albumin (BSA), whey protein isolate (WPI), whey protein hydrolysate (WPH), sodium caseinate (SC), carboxymethylcellulose sodium (CMC), fish gelatin (FG), high methoxyl apple pectin (HMAP), low methoxyl apple pectin (LMAP), gum Arabic (GA), ι-carrageenan (CGN), and hydroxypropyl chitosan (HPCTS) on physical stability of internal or external aqueous phase of water-in-oil-in-water (W/O/W) emulsions was evaluated. WPI and CGN in the internal aqueous phase, and GA, HPCTS, and CMC in the external phase reduced the size of emulsion droplets. BSA, WPI, SC, FG, CGN, and HPCTS improved the dilution stability of W/O/W emulsions, but HMAP had a negative effect. BSA, WPI, SC, FG, LMAP, GA, CGN, HPCTS, or CMC significantly improved the thermal stability of W/O/W emulsions. Results also indicated that the addition of CGN (1.0%), HMAP (1.0%), WPH (1.0%), or HPCTS (1.0%) in internal aqueous phase significantly increased the viscosity of emulsions, however, addition to the external aqueous phase had insignificant effects. A protein-knockout experiment confirmed that proteins as biomacromolecules, were the key factor in improving physical stability of emulsions.

19.
Soft Matter ; 11(21): 4290-4, 2015 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-25907429

RESUMEN

Underwater superoleophobic materials with low adhesion have been widely researched owing to their self-cleaning and anti-corrosive properties. In this study, polypyrrole (PPy) nanowire meshes have been successfully fabricated by in situ electrochemical polymerization on stainless steel mesh substrates in the presence of phosphate buffered saline as both an electrolyte and a dopant. PPy nanowire meshes have high oil contact angles (above 150°) and low sliding angles (less than 10°), and they show underwater superoleophobicity with an excellent self-cleaning performance, not only in pure water, but also in highly corrosive aqueous solutions, including salt solutions, strong acids or basic solutions. PPy nanowire meshes presented here show promise for potential applications in fields such as oil-water separation and marine oil spill clean-up.


Asunto(s)
Nanocables/química , Polímeros/química , Pirroles/química , Técnicas Electroquímicas , Electrólitos/química , Interacciones Hidrofóbicas e Hidrofílicas , Polimerizacion , Soluciones/química , Acero Inoxidable/química
20.
Int J Syst Evol Microbiol ; 64(Pt 6): 2108-2112, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24682704

RESUMEN

A Gram-reaction-negative, rod-shaped, non-motile, red-pigmented, radiation-resistant, aerobic bacterium designated T-3(T) was isolated from a soil sample from the Qinghai-Tibet Plateau in Tibet, China, after exposure to 10 kGy gamma radiation. Phylogenetic analysis based on 16S rRNA sequences indicated that this isolate represented a novel member of the genus Hymenobacter. Sequence identities of the 16S rRNA gene of strain T-3(T) with the type strains of species of the genus Hymenobacter with validly published names range from 89% to 97%, and the most closely related species is Hymenobacter psychrotolerans Tibet-IIU11(T) (97%). The DNA-DNA relatedness between strain T-3(T) and H. psychrotolerans is 59.10%. The major fatty acids of strain T-3(T) were iso-C(15 : 0) (27.66%), summed feature 4 (iso-C(17 : 1)I and/or anteiso-C(17 : 1)B, 15.84%), anteiso-C(15 : 0) (14.08%) and summed feature 3 (C(16 : 1)ω7c and/or C(16 : 1)ω6c, 12.38%). The major menaquinone of strain T-3(T) was MK-7. Phosphatidylethanolamine (PE) was predominant in the polar lipid profile. The G+C content of the DNA of strain T-3(T) was 69.17 mol%. On the basis of the results of the polyphasic characterization presented in this study, it is concluded that strain T-3(T) represents a novel species of the genus Hymenobacter, for which the name Hymenobacter kanuolensis is proposed. The type strain is T-3(T) ( = ACCC 05760(T) = KCTC 32407(T)).


Asunto(s)
Cytophagaceae/clasificación , Cytophagaceae/efectos de la radiación , Filogenia , Tolerancia a Radiación , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , China , Cytophagaceae/genética , Cytophagaceae/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/química , Rayos gamma , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Fosfatidiletanolaminas/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
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