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1.
Sensors (Basel) ; 21(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065434

RESUMO

In unpredictable disaster scenarios, it is important to recognize the situation promptly and take appropriate response actions. This study proposes a cloud computing-based data collection, processing, and analysis process that employs a crowd-sensing application. Clustering algorithms are used to define the major damage types, and hotspot analysis is applied to effectively filter critical data from crowdsourced data. To verify the utility of the proposed process, it is applied to Icheon-si and Anseong-si, both in Gyeonggi-do, which were affected by heavy rainfall in 2020. The results show that the types of incident at the damaged site were effectively detected, and images reflecting the damage situation could be classified using the application of the geospatial analysis technique. For 5 August 2020, which was close to the date of the event, the images were classified with a precision of 100% at a threshold of 0.4. For 24-25 August 2020, the image classification precision exceeded 95% at a threshold of 0.5, except for the mudslide mudflow in the Yul area. The location distribution of the classified images showed a distribution similar to that of damaged regions in unmanned aerial vehicle images.


Assuntos
Algoritmos , Smartphone , Computação em Nuvem , República da Coreia
2.
Molecules ; 25(13)2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32646056

RESUMO

The NLRP3 (NACHT, LRR and PYD domains-containing protein 3) inflammasome has been implicated in a variety of diseases, including atherosclerosis, neurodegenerative diseases, and infectious diseases. Thus, inhibitors of NLRP3 inflammasome have emerged as promising approaches to treat inflammation-related diseases. The aim of this study was to explore the effects of juglone (5-hydroxyl-1,4-naphthoquinone) on NLRP3 inflammasome activation. The inhibitory effects of juglone on nitric oxide (NO) production were assessed in lipopolysaccharide (LPS)-stimulated J774.1 cells by Griess assay, while its effects on reactive oxygen species (ROS) and NLRP3 ATPase activity were assessed. The expression levels of NLRP3, caspase-1, and pro-inflammatory cytokines (IL-1ß, IL-18) and cytotoxicity of juglone in J774.1 cells were also determined. Juglone was non-toxic in J774.1 cells when used at 10 µM (p < 0.01). Juglone treatment inhibited the production of ROS and NO. The levels of NLRP3 and cleaved caspase-1, as well as the secretion of IL-1ß and IL-18, were decreased by treatment with juglone in a concentration-dependent manner. Juglone also inhibited the ATPase activities of NLRP3 in LPS/ATP-stimulated J774.1 macrophages. Our results suggested that juglone could inhibit inflammatory cytokine production and NLRP3 inflammasome activation in macrophages, and should be considered as a therapeutic strategy for inflammation-related diseases.


Assuntos
Lipopolissacarídeos/toxicidade , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Naftoquinonas/farmacologia , Animais , Linhagem Celular , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Angew Chem Int Ed Engl ; 59(26): 10301-10305, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32080948

RESUMO

When components of a metal-organic framework (MOF) and a crystal growth modulator diffuse through a gel medium, they can form arrays of regularly-spaced precipitation bands containing MOF crystals of different morphologies. With time, slow variations in the local concentrations of the growth modulator cause the crystals to change their shapes, ultimately resulting in unusual concave microcrystallites not available via solution-based methods. The reaction-diffusion and periodic precipitation phenomena 1) extend to various types of MOFs and also MOPs (metal-organic polyhedra), and 2) can be multiplexed to realize within one gel multiple growth conditions, in effect leading to various crystalline phases or polycrystalline formations.

4.
Small ; 10(20): 4142-6, 2014 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24913824

RESUMO

About 30 nm quantum-dot thin films are formed by electrospray deposition (ESD) process and quantum-dot-light-emitting-diodes (QD-LEDs) are demonstrated. Maximum brightness of 23 000 cd m(-2) and current efficiency of 5.9 cd A(-1) are achieved with the ESD process. The ESD process can be a potential solution for large area quantum dot layers with simple and flexible control.

5.
Mycologia ; 106(3): 369-78, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24871589

RESUMO

Allomyces macrogynus produces zoosporangia that discharge uninucleate zoospores after cleavage of multinucleate cytoplasm. Cleavage of cytoplasm within the oligonucleate zoosporangia of A. macrogynus was visualized by constructing three-dimensional models based on electron micrographs and confocal images. In oligonucleate zoosporangia, three adjacent nuclei can form three cleavage planes with a line of intersection of the planes. The position and boundary of the cleavage planes are thought to be determined by the relative positions of the nuclei. The establishment of three cleavage planes by cleavage membranes occurred sequentially, and the nuclear axis connecting the centers of two nuclei affected the development of cleavage membranes on each cleavage plane. In multinucleate zoosporangia, groups of three neighboring nuclei near the cell cortex may initiate the sequential establishment of cleavage planes and then may interact with the nuclei further from the cortex until the interactions of nuclei are propagated to the central region of the cytoplasm.


Assuntos
Citocinese , Citoplasma/genética , Fungos/citologia , Esporos Fúngicos/citologia , Núcleo Celular/genética , Núcleo Celular/ultraestrutura , Citoplasma/ultraestrutura , Fungos/genética , Fungos/ultraestrutura , Imageamento Tridimensional , Microscopia Eletrônica de Transmissão , Esporos Fúngicos/genética , Esporos Fúngicos/ultraestrutura
6.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 9): o922, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25309254

RESUMO

The title compound, C2H3N3OS, is a monoclinic (P21/c) polymorph of the previously reported triclinic structure [Kang et al. (2012 ▶). Acta Cryst. E68, o1198]. The asymmetric unit contains two independent mol-ecules which are essentially planar, with r.m.s. deviations of 0.001 and 0.032 Šfrom the mean plane defined by the seven non-H atoms. In the crystal, N-H⋯N and N-H⋯O hydrogen bonds link the mol-ecules into a sheet parallel to (111).

7.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 9): m309, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25309174

RESUMO

In the complex cation of the title salt, [CrCl(C2H6OS)5]Cl2, the Cr(III) ion is coordinated by one chloride ligand and five O atoms from dimethyl sulfoxide (DMSO) ligands, leading to a slightly distorted octa-hedral coordination environment [O-Cr-O angles range from 86.69 (16) to 92.87 (16)°]. In the crystal, complex cations are arranged in hexa-gonally packed rows parallel to [010], with the chloride counter-anions situated in between. The inter-actions between cations and anions are mainly ionic in nature.

8.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 12): o1760, 2013 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-24454211

RESUMO

The title compound, C9H9N3O2S, is a monoclinic (C2/c) polymorph of the previously reported triclinic structure [Kang (2013 ▶). Acta Cryst. E69, o1327]. The mol-ecule is almost planar with an r.m.s. deviation of 0.069 Šfrom the mean plane of all non-H atoms. The benzoyl and terminal thio-urea fragments adopt a transoid conformation with respect to the central carbonyl O atom. Two intra-molecular N-H⋯O hydrogen bonds are present. In the crystal, N-H⋯O and N-H⋯S inter-actions link the mol-ecules into zigzag chains extending along the c-axis direction.

9.
Front Vet Sci ; 10: 1095877, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662989

RESUMO

The primary purpose of this research is to determine the effect of Amino-Zn (AZn), Yucca schidigera extract (YE), and ß-mannanase enzyme supplementation on growth performance, nutrient digestibility, fecal gas emission, and immune response in pigs. A total of 180 crossbred pigs (6.57 ± 1 kg) were randomly assigned to one of three dietary treatments: CON-corn soybean meal (basal diet); TRT1-CON +1,000 ppm AZn + 0.07% yucca extract (YE) + 0.05% ß-mannanase; and TRT2-CON +2,000 ppm AZn + 0.07% YE+ 0.05% ß-mannanase for 22 weeks. Each treatment had 12 replicates with 5 pigs per pen. Pigs fed a diet supplemented with AZn, YE, and ß-mannanase linearly increased (p < 0.05) BW and average daily gain at weeks 6, 12, 17, and 18. In contrast, the gain-to-feed ratio showed a linear increase (p < 0.05) from weeks 6 to 17 and the overall trial period. Moreover, the inclusion of experimental diets linearly decreased (p > 0.05) noxious gas emissions such as ammonia, hydrogen sulfide, acetic acid, carbon dioxide, and methyl mercaptans. The dietary inclusion of AZn, YE, and ß-mannanase significantly increased the serological immune responses to Mycoplasma hyopneumoniae (MH) and foot-and-mouth disease virus (FMDV-O type) at the end of week 6 and porcine circovirus-2 (PCV-2) at week 19. Based on this result, we infer that the combination of AZn, YE, and ß-mannanase supplement would serve as a novel in-feed additive to enhance growth performance and act as a boosting agent and immune stimulatory to increase the efficacy of swine vaccinations.

10.
Adv Sci (Weinh) ; 10(3): e2205588, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36442856

RESUMO

Using energy-saving electrochromic (EC) displays in smart devices for augmented reality makes cost-effective, easily producible, and efficiently operable devices for specific applications possible. Prussian blue (PB) is a metal-organic coordinated compound with unique EC properties that limit EC display applications due to the difficulty in PB micro-patterning. This work presents a novel micro-printing strategy for PB patterns using localized crystallization of FeFe(CN)6 on a substrate confined by the acidic-ferric-ferricyanide ink meniscus, followed by thermal reduction at 120 °C, thereby forming PB. Uniform PB patterns can be obtained by manipulating printing parameters, such as the concentration of FeCl3 ·K3 Fe(CN)6 , printing speed, and pipette inner diameter. Using a 0.1 M KCl (pH 4) electrolyte, the printed PB pattern is consistently and reversibly converted to Prussian white (CV potential range: -0.2-0.5 V) with 200 CV cycles. The PB-based EC display with a navigation function integrated into a smart contact lens is able to display directions to a destination to a user by receiving GPS coordinates in real time. This facile method for forming PB micro-patterns could be used for advanced EC displays and various functional devices.

11.
Polymers (Basel) ; 13(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070689

RESUMO

The bamboo fiber-based composite (BFBC) has high-performce in terms of mechanical properties and dimensional stability. In this study, BFBCs were prepared with different hot-pressing temperatures (150 °C, 160 °C, 170 °C, 180 °C, 190 °C, and 200 °C) and designed with different densities (1.05 g/cm3, 1.10 g/cm3, 1.15 g/cm3 and 1.20 g/cm3), and their selected properties were evaluated. Temperature affected BFBC performance, which, with a general increase in temperature, showed a decrement in mechanical properties and an improvement in dimensional stability. Holocellulose content significantly decreased, and the color of BFBC became darker with the increasing of the press temperature. As the density of BFBC increased, the modulus of elasticity (MOE) significantly increased from 23.09 GPa to 27.01 GPa with the increase in temperature. The thickness swelling ratio (TSR), width swelling ratio (WSR) and water absorption ratio (WAR) declined by more than 30% with the increase in density. Overall, the results of this study provide a theoretical basis and a source of technical support to promote the design, application, and popularization of BFBC in different fields.

12.
Polymers (Basel) ; 13(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200423

RESUMO

This study aimed to evaluate the effect of ammonium persulfate's (APS) oxidation time on the characteristics of the cellulose nanocrystals (CNCs) of balsa and kapok fibers after delignification pretreatment with sodium chlorite/acetic acid. This two-step method is important for increasing the zeta potential value and achieving higher thermal stability. The fibers were partially delignified using acidified sodium chlorite for four cycles, followed by APS oxidation at 60 °C for 8, 12, and 16 h. The isolated CNCs with a rod-like structure showed an average diameter in the range of 5.5-12.6 nm and an aspect ratio of 14.7-28.2. Increasing the reaction time resulted in a gradual reduction in the CNC dimensions. The higher surface charge of the balsa and kapok CNCs was observed at a longer oxidation time. The CNCs prepared from kapok had the highest colloid stability after oxidation for 16 h (-62.27 mV). The CNCs with higher crystallinity had longer oxidation times. Thermogravimetric analysis revealed that the CNCs with a higher thermal stability had longer oxidation times. All of the parameters were influenced by the oxidation time. This study indicates that APS oxidation for 8-16 h can produce CNCs from delignified balsa and kapok with satisfactory zeta potential values and thermal stabilities.

13.
Fungal Genet Biol ; 47(8): 713-20, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20452449

RESUMO

Allomyces macrogynus, a true fungus, produces zoosporangia which discharge uninucleate zoospores after cytoplasmic cleavage. Binucleate zoosporangia of A. macrogynus were induced and examined to understand the basic principles of cytokinesis associated with the multinucleate zoosporangia. Development of cleavage membranes was visualized by constructing three dimensional models based on electron micrographs and confocal images. Cleavage membranes on the cleavage plane showed asymmetric ingression from the cortex, but cleavage of cytoplasm was completed by the fusion of cleavage membranes with plasma membrane. Also, the position of the cleavage plane was continuously rotated until settled at the last stage. These studies suggest that the positions of the numerous cleavage planes within a multinucleate zoosporangium are continuously adjusted during development of cleavage membranes. The final settlement of cleavage planes would define the exact boundary of cleavage planes and the expansion of cleavage membranes toward the boundary could complete the cleavage of cytoplasm.


Assuntos
Allomyces/crescimento & desenvolvimento , Citocinese , Esporos Fúngicos/crescimento & desenvolvimento , Allomyces/citologia , Imageamento Tridimensional , Microscopia Confocal , Microscopia Eletrônica , Esporos Fúngicos/citologia
14.
Nanotechnology ; 21(40): 405201, 2010 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-20823496

RESUMO

High quality graphene was obtained though microwave irradiated expansion following a solution process. This method is facile, inexpensive, and produces usable results. Ultrathin, uniform graphene films were fabricated at room temperature by a vacuum filtration method. Combining carbon nanotubes (CNTs) as bridges between graphene flakes allowed the fabrication of high-performance conductive films for flexible applications, with conductivities and optical properties comparable to commercial ITO: 181 Omega sq(-1) at 82.2% transmittance after chemical treatment and doping. With future work, this versatile material could well provide an appropriate transparent electrode for flexible optical electronics.

15.
Sci Rep ; 10(1): 6258, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32277119

RESUMO

Four-dimensional (4D) printing can add active and responsive functions to three-dimensional (3D) printed objects in response to various external stimuli. Light, among others, has a unique advantage of remotely controlling structural changes to obtain predesigned shapes. In this study, we demonstrate multicolor 4D printing of shape-memory polymers (SMPs). Using color-dependent selective light absorption and heating in multicolor SMP composites, we realize remote actuation with light illumination. We experimentally investigate the temperature changes in colored SMPs and observe a clear difference between the different colors. We also present simulations and analytical calculations to theoretically model the structural variations in multicolor composites. Finally, we consider a multicolor hinged structure and demonstrate the multistep actuation by changing the color of light and duration of illumination. 4D printing can allow complex, multicolor geometries with predesigned responses. Moreover, SMPs can be reused multiple times for thermal actuation by simply conducting thermomechanical programming again. Therefore, 4D printing of multicolor SMP composites have unique merits for light-induced structural changes. Our study indicates that multicolor 4D printing of SMPs are promising for various structural changes and remote actuation.

16.
Polymers (Basel) ; 12(10)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32992855

RESUMO

Changes in the dimensions of lignocellulose nanofibrils (LCNFs) with different lignin contents from betung bamboo (Dendrocalamus asper) by enzymatic hydrolysis using endoglucanase (EG) were investigated. Lignin contents were adjusted from 3% to 27% by NaClO2/acetic acid treatment, and LCNFs were prepared using a wet disk-mill (WDM). The dimensions of the LCNFs significantly decreased with decreasing lignin content and increasing EG addition. With increasing EG content, the average diameter of the LCNFs significantly decreased, even though they contained parts of hemicellulose and lignin. The crystal structure showed the typical cellulose I structure in all samples, but the intensity of the diffraction peak slightly changed depending on the lignin and EG contents. The crystallinity index (CrI) values of the LCNFs increased a maximum of 23.8% (LCNF-L27) under increasing EG addition, regardless of the lignin content. With the EG addition of three times the LCNF amount, LCNF-L3 showed the highest CrI value (59.1%). By controlling the composition and structure of LCNFs, it is expected that the wide range of properties of these materials can extend the property range available for existing materials.

17.
Polymers (Basel) ; 12(1)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936376

RESUMO

The adsorption characteristics of silver nanoparticles (AgNPs) on cellulose nanofibrils (CNFs) were investigated herein with different chemical compositions. Pure cellulose nanofibers (PCNFs), lignocellulose nanofibers (LCNFs) with different lignin contents (LCNF-20% and LCNF-31%), and holocellulose nanofibers (HCNFs) with hemicellulose were used in this study. Furthermore, CNFs and silver nitrate were mixed and reacted at different temperatures, and NaBH4 was used as the reducing agent. First, the effect of temperature on the adsorption of AgNPs on PCNF was studied. At an optimal temperature (45 °C), the effect of the chemical composition of CNF was studied. The overall properties were analyzed using UV-vis spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The AgNPs were found to be spherical under all conditions with average diameter of 5.3 nm (PCNF), 5.6 nm (HCNF), 6.3 nm (LCNF-20%) and 6.6 nm (LCNF-31%). The amount of AgNPs adsorbed on the CNF was observed to vary, based on the chemical composition of the CNF. The adsorption amount of AgNPs was observed to increase in the order of LCNF-20% > PCNF > LCNF-31% > HCNF. The results indicated that phenolic hydroxyl groups present in LCNF significantly affected the adsorption of AgNPs.

18.
Korean J Fam Med ; 41(5): 312-317, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32434303

RESUMO

BACKGROUND: Dry sauna treatments improve the quality of life for chronic pain, congestive heart failure, and type 2 diabetes patients. This study aimed to determine whether dry sauna therapy improved the quality of life of obese people. METHODS: A total of 38 consecutive participants aged over 20 years with a body mass index of ≥25 kg/m2 were recruited for the study. The participants were treated with a 90°C dry sauna for 15 minutes, twice daily for 4 consecutive days. To assess the quality of life, all participants completed the 5 level EQ-5D questionnaires and the EQ-Visual Analog Scale. Study parameters were measured on the same day prior to commencing the sauna sessions in a fasted state and 2 days after the last sauna session. RESULTS: The average age was 62.3±9.5 years; 84.2% of the participants were female. The mean body mass index was 28.5±2.4 kg/m2. Dry sauna significantly improved the mean 5 level EQ-5D index scores from 0.83±0.12 to 0.89±0.11 and increased the mean EQ-Visual Analog Scale from 79.0±15.2 to 91.1±9.7. However, there were no significant changes in body mass index, blood pressure, heart rate, or body composition before and after the 8-session sauna therapy. CONCLUSION: Dry sauna improved the health-related quality of life of obese patients without adverse events. Further clinical studies in larger study populations are needed to verify these findings and provide concrete evidence for obesity treatment.

19.
Materials (Basel) ; 13(13)2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32630791

RESUMO

The discovery of ferroelectricity in HfO2-based materials in 2011 provided new research directions and opportunities. In particular, for atomic layer deposited Hf0.5Zr0.5O2 (HZO) films, it is possible to obtain homogenous thin films with satisfactory ferroelectric properties at a low thermal budget process. Based on experiment demonstrations over the past 10 years, it is well known that HZO films show excellent ferroelectricity when sandwiched between TiN top and bottom electrodes. This work reports a comprehensive study on the effect of TiN top and bottom electrodes on the ferroelectric properties of HZO thin films (10 nm). Investigations showed that during HZO crystallization, the TiN bottom electrode promoted ferroelectric phase formation (by oxygen scavenging) and the TiN top electrode inhibited non-ferroelectric phase formation (by stress-induced crystallization). In addition, it was confirmed that the TiN top and bottom electrodes acted as a barrier layer to hydrogen diffusion into the HZO thin film during annealing in a hydrogen-containing atmosphere. These features make the TiN electrodes a useful strategy for improving and preserving the ferroelectric properties of HZO thin films for next-generation memory applications.

20.
J Biomech ; 42(1): 29-34, 2009 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-19062017

RESUMO

Reaching tasks are considered well-executed if they appear "smooth," a quality that is typically quantified by its opposite, jerk, the rate of change of acceleration. While jerk is a theoretically sound measure, its application to spastic individuals sometimes yields counter-intuitive results, and does not reveal motor impairment across the workspace. To more generally quantify spontaneous accelerative transients (SATs) within a movement, a pseudo-wavelet transform was devised that iteratively compared angular trajectories to a series of straight-line approximants. Cumulative linear fit errors were expressed in terms of flexion angle, yielding an SAT map of the entire motion. To compare SAT maps with traditional smoothness measures, two scalar indices were extracted from them: residual excursion deviation (RED), representing the integral over Deltatheta and the ratio of peak error to mean error (PEME) on the map. Fifteen subjects, including five subjects with chronic stroke performed elbow flexions throughout their entire ranges of motion, Deltatheta, at a comfortable pace with their arms supported in the transverse plane. Maps revealed that stroke subjects were significantly less coordinated than controls, as measured both by RED: 8.0+/-2.9 x 10(-3) versus 3.1+/-0.8 x 10(-3) and PEME: 6.6+/-0.9 versus 12.1+/-1.9, both P<0.001. Comparable jerk metrics, including integrated average jerk, did not report a significant performance deficit at the P<0.05 level. Map metrics for all subjects were independent of average velocity (correlation with theta : rho0.31), but jerk-based metrics for stroke subjects were spuriously co-variant with velocity rho=0.85, which may relate to the significantly higher mean arrest period ratio in stroke subjects (0.26+/-0.19 versus 0.09+/-0.08, P<0.001). We conclude that SAT maps provide reliable information on regional movement impairments at a wide range of proficiency levels.


Assuntos
Aceleração , Cotovelo/fisiologia , Destreza Motora/fisiologia , Biofísica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/fisiopatologia
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