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1.
Int J Mol Sci ; 22(3)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33513971

RESUMO

To improve the oxidative stability of biodiesel fuel (BDF), the polyunsaturated fatty acid methyl esters (poly-FAME) presented in commercial palm oil-derived biodiesel fuel (palm-BDF) were selectively hydrogenated to monounsaturated fatty acid methyl esters (mono-FAME) under a mild condition (80 °C, 0.5 MPa) using activated carbon (AC)-supported Pd catalysts with a Pd loading of 1 wt.%. The partially hydrotreated palm-BDF (denoted as H-FAME) which has low poly-FAME components is a new type of BDF with enhanced quality for use in high blends. In this study, we reported that the chemical states and particle sizes of Pd in the prepared Pd/AC catalysts were significantly influenced by the Pd precursors, Pd(NO3)2 and Pd(NH3)4Cl2, and thus varied their hydrogenation activity and product selectivity. The 1%Pd/AC (nit) catalyst, prepared using Pd(NO3)2, presented high performance for selective hydrogenation of poly-FAME into mono-FAME with high oxidation stability, owning to its large Pd particles (8.4 nm). Conversely, the 1%Pd/AC (amc) catalyst, prepared using Pd(NH3)4Cl2, contained small Pd particles (2.7 nm) with a little Cl residues, which could be completely removed by washing with an aqueous solution of 0.1 M NH4OH. The small Pd particles gave increased selectivity toward unwanted-FAME components, particularly the saturated fatty acid methyl esters during the hydrogenation of poly-FAME. This selectivity is unprofitable for improving the biodiesel quality.


Assuntos
Biocombustíveis , Carbono/metabolismo , Ácidos Graxos/metabolismo , Óleo de Palmeira/química , Catálise , Esterificação , Ésteres/química , Ácidos Graxos/química , Humanos , Hidrogênio/química , Hidrogenação , Oxirredução , Paládio/química
2.
Front Rehabil Sci ; 4: 1308706, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239627

RESUMO

Introduction: The aim of this study was to compare the clinical applicability of the Mini-Balance Evaluation Systems Test and the Berg Balance Scale for measuring balance in inpatients with subacute stroke. Methods: This was a prospective observational study which included 58 consecutive patients admitted to a convalescent rehabilitation hospital with a first-ever stroke and who met the inclusion/exclusion criteria. The Mini-Balance Evaluation Systems Test and the Berg Balance Scale were used to assess patient balance at admission and discharge. The ceiling and floor effects and responsiveness of each balance score were examined. In addition, receiver operating characteristic analysis based on each balance score at admission was used to examine its discriminative power to predict ambulatory independence and falls during hospitalization. Results: The mean (standard deviation) change between admission and discharge for each balance scale was 4.4 (4.7) for the Mini-Balance Evaluation Systems Test and 8.3 (10.0) for the Berg Balance Scale, with standard response means, a measure of responsiveness of 0.9 (large) and 0.8 (medium), respectively. Each balance score at admission almost equally predicted gait independence and fallers during hospitalization. On the contrary, only the distribution of scores on the Berg Balance Scale at discharge showed a ceiling effect, with 25 patients (43%) obtaining a perfect score. Discussion: The Mini-Balance Evaluation Systems Test may be useful as a balance measure for inpatients with subacute stroke because it is less susceptible to ceiling effects and more responsive than the Berg Balance Scale.

3.
Glycoconj J ; 27(2): 237-48, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20016933

RESUMO

N-acetylgalactosamine 4-sulfate 6-O-sulfotransferase (GalNAc4S-6ST) transfers sulfate to position 6 of GalNAc(4SO4) residues of chondroitin sulfate to yield chondroitin sulfate E (CS-E). We have previously demonstrated that phenyl-beta-D-GalNAc(4SO4) could serve as an acceptor for GalNAc4S-6ST, thereby inhibiting GalNAc4S-6ST competitively. In this paper we compared the inhibitory effects of various glycosides in which various hydrophobic aglycons were attached to D-GalNAc(4SO4) via ss anomeric configuration. p-Nitrophenyl-beta-D-GalNAc(4SO4) and p-chlorophenyl-beta-D-GalNAc(4SO4) were stronger inhibitors than phenyl-beta-D-GalNAc(4SO4). Among inhibitors examined here, 3-estradiol-beta-D-GalNAc(4SO4) was the strongest inhibitor; the Ki of 3-estradiol-beta-D-GalNAc(4SO4) for the competitive inhibition was 0.008 mM, which was much lower than the Ki of phenyl-beta-D-GalNAc(4SO4), 0.98 mM. In contrast, 7-estradiol-beta-D-GalNAc(4SO4) showed only weak inhibition to GalNAc4S-6ST. 3-Estradiol-beta-D-GalNAc(4SO4) did not inhibit chondroitin 6-sulfotransferase and chondroitin 4-sulfotransferase under the concentration where GalNAc4S-6ST was inhibited by 90%. When 3-estradiol-beta-D-GalNAc(4SO4) was added to the culture medium of chondrosarcoma cells expressing human GalNAc4S-6ST, a significant, albeit small, reduction in the cellular synthesis of CS-E was observed. These results suggest that estradiol group of 3-estradiol-beta-D-GalNAc(4SO4) may enhance the inhibitory activity of the glycoside through increasing the affinity to the enzyme and may allow the glycosides to diffuse at a low efficiency into the cells to inhibit cellular synthesis of CS-E.


Assuntos
Acetilgalactosamina/química , Acetilgalactosamina/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Sulfotransferases/antagonistas & inibidores , Configuração de Carboidratos , Linhagem Celular Tumoral , Sulfatos de Condroitina/biossíntese , Glicosídeos/química , Glicosídeos/farmacologia , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Cinética , Enxofre/metabolismo
4.
Prog Rehabil Med ; 3: 20180015, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-32789240

RESUMO

OBJECTIVE: The objective of the current study was to evaluate the reliability and validity of the Japanese version of the Mini-Balance Evaluation Systems Test (J-Mini-BESTest) in patients with subacute stroke. METHODS: Eighteen patients who had suffered a first hemiplegic stroke (mean age, 59.1 ± 27.0 years) and had been admitted to convalescent rehabilitation wards were enrolled. The J-Mini-BESTest, the Berg Balance Scale (BBS), and the functional reach test (FRT) were used to assess balance. Four physical therapists (PTs) observed and scored the J-Mini-BESTest while another PT conducted the test. The interrater reliability of the J-Mini-BESTest was assessed using intraclass correlation coefficients (ICC[2,1]) for the total and section scores, and kappa statistics for each item. Internal consistency of the five raters was assessed using Cronbach's alpha. Concurrent validity of the J-Mini-BESTest was assessed against the BBS and FRT using Spearman's correlation coefficients. RESULTS: The ICC[2,1] of the total and section scores were 0.90 (95% confidence interval: 0.81-0.95) and 0.63-0.85, respectively. Cronbach's alphas were 0.80-0.87. The kappa statistics were 0.47-1.00. The scores of the J-Mini-BESTest were significantly correlated with those of the BBS (rho=0.66, p=0.006) but not with those of the FRT (rho=-0.36, p=0.189). CONCLUSION: The J-Mini-BESTest showed excellent inter-rater reliability and internal consistency. Although the J-Mini-BESTest was not correlated with the FRT, it was significantly correlated with the BBS. The J-Mini-BESTest is a reliable and valid tool for evaluating dynamic balance in patients with subacute stroke.

5.
J Colloid Interface Sci ; 508: 415-418, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28858650

RESUMO

Nanoporous carbons can preferentially adsorb bromide ions from an aqueous solution of alkali metal bromides, even on π-conjugated surfaces. Our results show a new adsorption mechanism whereby coadsorption of protons enhances the adsorption of the anions onto the carbons.

6.
ACS Nano ; 5(2): 811-9, 2011 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-21210712

RESUMO

A novel composite is presented as a supercapacitor electrode with a high maximum power rating (990 kW/kg; 396 kW/l) exceeding power performances of other electrodes. The high-power capability of the electrode stemmed from its unique meso-macro pore structure engineered through the utilization of single-walled carbon nanotubes (20 wt %) as scaffolding for single-walled carbon nanohorns (80 wt %). The novel composite electrode also exhibited durable operation (6.5% decline in capacitance over 100 000 cycles) as a result of its monolithic chemical composition and mechanical stability. The novel composite electrode was benchmarked against another high-power electrode made from single-walled carbon nanotubes (Bucky paper electrode). While the composite electrode had a lower surface area compared to the Bucky paper electrode (280 vs 470 m(2)/g from nitrogen adsorption), it had a higher meso-macro pore volume (2.6 vs 1.6 mL/g from mercury porosimetry) which enabled the composite electrode to retain more electrolyte, ensuring facile ion transport, hence achieving a higher maximum power rating (970 vs 400 kW/kg).

7.
IEEE Trans Neural Netw ; 20(10): 1540-53, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19717359

RESUMO

In this paper, we define the naturalness of handwritten characters as being the difference between the strokes of the handwritten characters and the archetypal fonts on which they are based. With this definition, we mathematically analyze the relationship between the font and its naturalness using canonical correlation analysis (CCA), multiple linear regression analysis, feedforward neural networks (FFNNs) with sliding windows, and recurrent neural networks (RNNs). This analysis reveals that certain properties of font character strokes do not have a linear relationship with their naturalness. In turn, this suggests that nonlinear techniques should be used to model the naturalness, and in our investigations, we find that an RNN with a recurrent output layer performs the best among four linear and nonlinear models. These results indicate that it is possible to model naturalness, defined in our study as the difference between handwritten and archetypal font characters but more generally as the difference between the behavior of a natural system and a corresponding basic system, and that naturalness learning is a promising approach for generating handwritten characters.


Assuntos
Inteligência Artificial , Biometria/métodos , Biomimética/métodos , Escrita Manual , Modelos Teóricos , Reconhecimento Automatizado de Padrão/métodos , Simulação por Computador , Humanos
8.
J Physiol Anthropol Appl Human Sci ; 24(1): 81-5, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15684550

RESUMO

Users' fatigue is the biggest technological hurdle facing Interactive Evolutionary Computation (IEC). This paper introduces the idea of "absolute scale" and "neighbour scale" to improve the performance of predicting users' subjective evaluation characteristics in IEC, and thus it will accelerate EC convergence and reduce users' fatigue. We experimentally evaluate the effect of the proposed method using two benchmark functions. The experimental results show that the convergence speed of IEC using the proposed predictor, which learns from absolute evaluation data, is much faster than the conventional one, which learns from relative data, especially in early generations. Also, IEC with predictors that use recent data are more effective than those which use all past data.


Assuntos
Fadiga/fisiopatologia , Retroalimentação , Modelos Biológicos , Análise e Desempenho de Tarefas , Humanos
9.
J Physiol Anthropol Appl Human Sci ; 24(1): 77-80, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15684549

RESUMO

We propose and then evaluate a new framework for finding the physical parameters of an artificial environment which give rise to given target physiological characteristics. We assume that a human is a system that takes as inputs the physical parameters of an artificial environment and outputs physiological parameters in response. We define our task as the inverse problem; we must find the best inputs from given target outputs. Our proposed framework solves the inverse problem using evolutionary computation techniques to optimize an artificial environment. We evaluate this framework using a simulation with a vibration environment and verify that it works.


Assuntos
Ambiente Controlado , Retroalimentação , Modelos Neurológicos , Neurônios/fisiologia , Humanos
10.
J Physiol Anthropol Appl Human Sci ; 23(6): 313-7, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15599082

RESUMO

It is difficult to design the Virtual Reality (VR) Environment which controls VR sickness and promotes presence. This is because the relationship between the user's susceptibility to VR sickness and a sense of presence, determined by velocity and visual angle of the visual information, involves a trade-off between the two. Then we propose the optimal value search system which computes efficiently the velocity and visual angle which control VR sickness and do not impair presence by taking account of a subject's characteristic. Under certain experimental conditions, some subjects showed serious VR sickness whose simulator sickness questionnaire total score was more than 60 and needed more than 30 minutes to recover from VR sickness. However, on the condition of angular velocity and visual angle computed by our proposed method, all subjects felt their vection, which was our index for the sense of presence, over 70 percent of their experiment time; no subject needed more than 5 minutes to recover from VR sickness.


Assuntos
Enjoo devido ao Movimento/etiologia , Redes Neurais de Computação , Interface Usuário-Computador , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Enantiomer ; 7(2-3): 129-32, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12108630

RESUMO

Calix[4]arene tethering four chiral five-membered cyclic carbonates 1c was synthesized by O-glycidylation of p-tert-butylcalix[4]arene 1a with (R)-glycidyl tosylate, followed by carbonation with carbon dioxide catalyzed by lithium bromide. Porphyrin tethering chiral five-membered cyclic carbonates 2c was similarly synthesized.

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